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1bc38b8f | 1 | // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) |
6061a3d6 | 2 | |
1b76c13e WN |
3 | /* |
4 | * Common eBPF ELF object loading operations. | |
5 | * | |
6 | * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org> | |
7 | * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com> | |
8 | * Copyright (C) 2015 Huawei Inc. | |
f367540c | 9 | * Copyright (C) 2017 Nicira, Inc. |
d859900c | 10 | * Copyright (C) 2019 Isovalent, Inc. |
1b76c13e WN |
11 | */ |
12 | ||
b4269954 | 13 | #ifndef _GNU_SOURCE |
531b014e | 14 | #define _GNU_SOURCE |
b4269954 | 15 | #endif |
1b76c13e | 16 | #include <stdlib.h> |
b3f59d66 WN |
17 | #include <stdio.h> |
18 | #include <stdarg.h> | |
f367540c | 19 | #include <libgen.h> |
34090915 | 20 | #include <inttypes.h> |
8ab9da57 | 21 | #include <limits.h> |
b3f59d66 | 22 | #include <string.h> |
1b76c13e | 23 | #include <unistd.h> |
cdb2f920 | 24 | #include <endian.h> |
1a5e3fb1 WN |
25 | #include <fcntl.h> |
26 | #include <errno.h> | |
113e6b7e | 27 | #include <ctype.h> |
1b76c13e | 28 | #include <asm/unistd.h> |
e28ff1a8 | 29 | #include <linux/err.h> |
cb1e5e96 | 30 | #include <linux/kernel.h> |
1b76c13e | 31 | #include <linux/bpf.h> |
38d5d3b3 | 32 | #include <linux/btf.h> |
47eff617 | 33 | #include <linux/filter.h> |
f367540c | 34 | #include <linux/limits.h> |
438363c0 | 35 | #include <linux/perf_event.h> |
a64af0ef | 36 | #include <linux/ring_buffer.h> |
fb84b822 | 37 | #include <sys/epoll.h> |
63f2f5ee | 38 | #include <sys/ioctl.h> |
fb84b822 | 39 | #include <sys/mman.h> |
f367540c JS |
40 | #include <sys/stat.h> |
41 | #include <sys/types.h> | |
42 | #include <sys/vfs.h> | |
ddc7c304 | 43 | #include <sys/utsname.h> |
dc3a2d25 | 44 | #include <sys/resource.h> |
1a5e3fb1 WN |
45 | #include <libelf.h> |
46 | #include <gelf.h> | |
166750bc | 47 | #include <zlib.h> |
1b76c13e WN |
48 | |
49 | #include "libbpf.h" | |
52d3352e | 50 | #include "bpf.h" |
8a138aed | 51 | #include "btf.h" |
6d41907c | 52 | #include "str_error.h" |
d7c4b398 | 53 | #include "libbpf_internal.h" |
ddc7c304 | 54 | #include "hashmap.h" |
67234743 | 55 | #include "bpf_gen_internal.h" |
c44fd845 | 56 | #include "zip.h" |
b3f59d66 | 57 | |
f367540c JS |
58 | #ifndef BPF_FS_MAGIC |
59 | #define BPF_FS_MAGIC 0xcafe4a11 | |
60 | #endif | |
61 | ||
9c0f8cbd AN |
62 | #define BPF_INSN_SZ (sizeof(struct bpf_insn)) |
63 | ||
ff466b58 AI |
64 | /* vsprintf() in __base_pr() uses nonliteral format string. It may break |
65 | * compilation if user enables corresponding warning. Disable it explicitly. | |
66 | */ | |
67 | #pragma GCC diagnostic ignored "-Wformat-nonliteral" | |
68 | ||
b3f59d66 WN |
69 | #define __printf(a, b) __attribute__((format(printf, a, b))) |
70 | ||
590a0088 | 71 | static struct bpf_map *bpf_object__add_map(struct bpf_object *obj); |
aea28a60 | 72 | static bool prog_is_subprog(const struct bpf_object *obj, const struct bpf_program *prog); |
590a0088 | 73 | |
ccde5760 DM |
74 | static const char * const attach_type_name[] = { |
75 | [BPF_CGROUP_INET_INGRESS] = "cgroup_inet_ingress", | |
76 | [BPF_CGROUP_INET_EGRESS] = "cgroup_inet_egress", | |
77 | [BPF_CGROUP_INET_SOCK_CREATE] = "cgroup_inet_sock_create", | |
78 | [BPF_CGROUP_INET_SOCK_RELEASE] = "cgroup_inet_sock_release", | |
79 | [BPF_CGROUP_SOCK_OPS] = "cgroup_sock_ops", | |
80 | [BPF_CGROUP_DEVICE] = "cgroup_device", | |
81 | [BPF_CGROUP_INET4_BIND] = "cgroup_inet4_bind", | |
82 | [BPF_CGROUP_INET6_BIND] = "cgroup_inet6_bind", | |
83 | [BPF_CGROUP_INET4_CONNECT] = "cgroup_inet4_connect", | |
84 | [BPF_CGROUP_INET6_CONNECT] = "cgroup_inet6_connect", | |
bf90438c | 85 | [BPF_CGROUP_UNIX_CONNECT] = "cgroup_unix_connect", |
ccde5760 DM |
86 | [BPF_CGROUP_INET4_POST_BIND] = "cgroup_inet4_post_bind", |
87 | [BPF_CGROUP_INET6_POST_BIND] = "cgroup_inet6_post_bind", | |
88 | [BPF_CGROUP_INET4_GETPEERNAME] = "cgroup_inet4_getpeername", | |
89 | [BPF_CGROUP_INET6_GETPEERNAME] = "cgroup_inet6_getpeername", | |
bf90438c | 90 | [BPF_CGROUP_UNIX_GETPEERNAME] = "cgroup_unix_getpeername", |
ccde5760 DM |
91 | [BPF_CGROUP_INET4_GETSOCKNAME] = "cgroup_inet4_getsockname", |
92 | [BPF_CGROUP_INET6_GETSOCKNAME] = "cgroup_inet6_getsockname", | |
bf90438c | 93 | [BPF_CGROUP_UNIX_GETSOCKNAME] = "cgroup_unix_getsockname", |
ccde5760 DM |
94 | [BPF_CGROUP_UDP4_SENDMSG] = "cgroup_udp4_sendmsg", |
95 | [BPF_CGROUP_UDP6_SENDMSG] = "cgroup_udp6_sendmsg", | |
bf90438c | 96 | [BPF_CGROUP_UNIX_SENDMSG] = "cgroup_unix_sendmsg", |
ccde5760 DM |
97 | [BPF_CGROUP_SYSCTL] = "cgroup_sysctl", |
98 | [BPF_CGROUP_UDP4_RECVMSG] = "cgroup_udp4_recvmsg", | |
99 | [BPF_CGROUP_UDP6_RECVMSG] = "cgroup_udp6_recvmsg", | |
bf90438c | 100 | [BPF_CGROUP_UNIX_RECVMSG] = "cgroup_unix_recvmsg", |
ccde5760 DM |
101 | [BPF_CGROUP_GETSOCKOPT] = "cgroup_getsockopt", |
102 | [BPF_CGROUP_SETSOCKOPT] = "cgroup_setsockopt", | |
103 | [BPF_SK_SKB_STREAM_PARSER] = "sk_skb_stream_parser", | |
104 | [BPF_SK_SKB_STREAM_VERDICT] = "sk_skb_stream_verdict", | |
105 | [BPF_SK_SKB_VERDICT] = "sk_skb_verdict", | |
106 | [BPF_SK_MSG_VERDICT] = "sk_msg_verdict", | |
107 | [BPF_LIRC_MODE2] = "lirc_mode2", | |
108 | [BPF_FLOW_DISSECTOR] = "flow_dissector", | |
109 | [BPF_TRACE_RAW_TP] = "trace_raw_tp", | |
110 | [BPF_TRACE_FENTRY] = "trace_fentry", | |
111 | [BPF_TRACE_FEXIT] = "trace_fexit", | |
112 | [BPF_MODIFY_RETURN] = "modify_return", | |
113 | [BPF_LSM_MAC] = "lsm_mac", | |
bffcf348 | 114 | [BPF_LSM_CGROUP] = "lsm_cgroup", |
ccde5760 DM |
115 | [BPF_SK_LOOKUP] = "sk_lookup", |
116 | [BPF_TRACE_ITER] = "trace_iter", | |
117 | [BPF_XDP_DEVMAP] = "xdp_devmap", | |
118 | [BPF_XDP_CPUMAP] = "xdp_cpumap", | |
119 | [BPF_XDP] = "xdp", | |
120 | [BPF_SK_REUSEPORT_SELECT] = "sk_reuseport_select", | |
121 | [BPF_SK_REUSEPORT_SELECT_OR_MIGRATE] = "sk_reuseport_select_or_migrate", | |
122 | [BPF_PERF_EVENT] = "perf_event", | |
123 | [BPF_TRACE_KPROBE_MULTI] = "trace_kprobe_multi", | |
8d1608d7 | 124 | [BPF_STRUCT_OPS] = "struct_ops", |
132328e8 | 125 | [BPF_NETFILTER] = "netfilter", |
fe20ce3a DB |
126 | [BPF_TCX_INGRESS] = "tcx_ingress", |
127 | [BPF_TCX_EGRESS] = "tcx_egress", | |
8097e460 | 128 | [BPF_TRACE_UPROBE_MULTI] = "trace_uprobe_multi", |
05c31b4a DB |
129 | [BPF_NETKIT_PRIMARY] = "netkit_primary", |
130 | [BPF_NETKIT_PEER] = "netkit_peer", | |
ccde5760 DM |
131 | }; |
132 | ||
ba5d1b58 DM |
133 | static const char * const link_type_name[] = { |
134 | [BPF_LINK_TYPE_UNSPEC] = "unspec", | |
135 | [BPF_LINK_TYPE_RAW_TRACEPOINT] = "raw_tracepoint", | |
136 | [BPF_LINK_TYPE_TRACING] = "tracing", | |
137 | [BPF_LINK_TYPE_CGROUP] = "cgroup", | |
138 | [BPF_LINK_TYPE_ITER] = "iter", | |
139 | [BPF_LINK_TYPE_NETNS] = "netns", | |
140 | [BPF_LINK_TYPE_XDP] = "xdp", | |
141 | [BPF_LINK_TYPE_PERF_EVENT] = "perf_event", | |
142 | [BPF_LINK_TYPE_KPROBE_MULTI] = "kprobe_multi", | |
143 | [BPF_LINK_TYPE_STRUCT_OPS] = "struct_ops", | |
d0fe92fb | 144 | [BPF_LINK_TYPE_NETFILTER] = "netfilter", |
55cc3768 | 145 | [BPF_LINK_TYPE_TCX] = "tcx", |
8097e460 | 146 | [BPF_LINK_TYPE_UPROBE_MULTI] = "uprobe_multi", |
05c31b4a | 147 | [BPF_LINK_TYPE_NETKIT] = "netkit", |
ba5d1b58 DM |
148 | }; |
149 | ||
3e6dc020 DM |
150 | static const char * const map_type_name[] = { |
151 | [BPF_MAP_TYPE_UNSPEC] = "unspec", | |
152 | [BPF_MAP_TYPE_HASH] = "hash", | |
153 | [BPF_MAP_TYPE_ARRAY] = "array", | |
154 | [BPF_MAP_TYPE_PROG_ARRAY] = "prog_array", | |
155 | [BPF_MAP_TYPE_PERF_EVENT_ARRAY] = "perf_event_array", | |
156 | [BPF_MAP_TYPE_PERCPU_HASH] = "percpu_hash", | |
157 | [BPF_MAP_TYPE_PERCPU_ARRAY] = "percpu_array", | |
158 | [BPF_MAP_TYPE_STACK_TRACE] = "stack_trace", | |
159 | [BPF_MAP_TYPE_CGROUP_ARRAY] = "cgroup_array", | |
160 | [BPF_MAP_TYPE_LRU_HASH] = "lru_hash", | |
161 | [BPF_MAP_TYPE_LRU_PERCPU_HASH] = "lru_percpu_hash", | |
162 | [BPF_MAP_TYPE_LPM_TRIE] = "lpm_trie", | |
163 | [BPF_MAP_TYPE_ARRAY_OF_MAPS] = "array_of_maps", | |
164 | [BPF_MAP_TYPE_HASH_OF_MAPS] = "hash_of_maps", | |
165 | [BPF_MAP_TYPE_DEVMAP] = "devmap", | |
166 | [BPF_MAP_TYPE_DEVMAP_HASH] = "devmap_hash", | |
167 | [BPF_MAP_TYPE_SOCKMAP] = "sockmap", | |
168 | [BPF_MAP_TYPE_CPUMAP] = "cpumap", | |
169 | [BPF_MAP_TYPE_XSKMAP] = "xskmap", | |
170 | [BPF_MAP_TYPE_SOCKHASH] = "sockhash", | |
171 | [BPF_MAP_TYPE_CGROUP_STORAGE] = "cgroup_storage", | |
172 | [BPF_MAP_TYPE_REUSEPORT_SOCKARRAY] = "reuseport_sockarray", | |
173 | [BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE] = "percpu_cgroup_storage", | |
174 | [BPF_MAP_TYPE_QUEUE] = "queue", | |
175 | [BPF_MAP_TYPE_STACK] = "stack", | |
176 | [BPF_MAP_TYPE_SK_STORAGE] = "sk_storage", | |
177 | [BPF_MAP_TYPE_STRUCT_OPS] = "struct_ops", | |
178 | [BPF_MAP_TYPE_RINGBUF] = "ringbuf", | |
179 | [BPF_MAP_TYPE_INODE_STORAGE] = "inode_storage", | |
180 | [BPF_MAP_TYPE_TASK_STORAGE] = "task_storage", | |
181 | [BPF_MAP_TYPE_BLOOM_FILTER] = "bloom_filter", | |
583c1f42 | 182 | [BPF_MAP_TYPE_USER_RINGBUF] = "user_ringbuf", |
4fe64af2 | 183 | [BPF_MAP_TYPE_CGRP_STORAGE] = "cgrp_storage", |
3e6dc020 DM |
184 | }; |
185 | ||
d18616e7 DM |
186 | static const char * const prog_type_name[] = { |
187 | [BPF_PROG_TYPE_UNSPEC] = "unspec", | |
188 | [BPF_PROG_TYPE_SOCKET_FILTER] = "socket_filter", | |
189 | [BPF_PROG_TYPE_KPROBE] = "kprobe", | |
190 | [BPF_PROG_TYPE_SCHED_CLS] = "sched_cls", | |
191 | [BPF_PROG_TYPE_SCHED_ACT] = "sched_act", | |
192 | [BPF_PROG_TYPE_TRACEPOINT] = "tracepoint", | |
193 | [BPF_PROG_TYPE_XDP] = "xdp", | |
194 | [BPF_PROG_TYPE_PERF_EVENT] = "perf_event", | |
195 | [BPF_PROG_TYPE_CGROUP_SKB] = "cgroup_skb", | |
196 | [BPF_PROG_TYPE_CGROUP_SOCK] = "cgroup_sock", | |
197 | [BPF_PROG_TYPE_LWT_IN] = "lwt_in", | |
198 | [BPF_PROG_TYPE_LWT_OUT] = "lwt_out", | |
199 | [BPF_PROG_TYPE_LWT_XMIT] = "lwt_xmit", | |
200 | [BPF_PROG_TYPE_SOCK_OPS] = "sock_ops", | |
201 | [BPF_PROG_TYPE_SK_SKB] = "sk_skb", | |
202 | [BPF_PROG_TYPE_CGROUP_DEVICE] = "cgroup_device", | |
203 | [BPF_PROG_TYPE_SK_MSG] = "sk_msg", | |
204 | [BPF_PROG_TYPE_RAW_TRACEPOINT] = "raw_tracepoint", | |
205 | [BPF_PROG_TYPE_CGROUP_SOCK_ADDR] = "cgroup_sock_addr", | |
206 | [BPF_PROG_TYPE_LWT_SEG6LOCAL] = "lwt_seg6local", | |
207 | [BPF_PROG_TYPE_LIRC_MODE2] = "lirc_mode2", | |
208 | [BPF_PROG_TYPE_SK_REUSEPORT] = "sk_reuseport", | |
209 | [BPF_PROG_TYPE_FLOW_DISSECTOR] = "flow_dissector", | |
210 | [BPF_PROG_TYPE_CGROUP_SYSCTL] = "cgroup_sysctl", | |
211 | [BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE] = "raw_tracepoint_writable", | |
212 | [BPF_PROG_TYPE_CGROUP_SOCKOPT] = "cgroup_sockopt", | |
213 | [BPF_PROG_TYPE_TRACING] = "tracing", | |
214 | [BPF_PROG_TYPE_STRUCT_OPS] = "struct_ops", | |
215 | [BPF_PROG_TYPE_EXT] = "ext", | |
216 | [BPF_PROG_TYPE_LSM] = "lsm", | |
217 | [BPF_PROG_TYPE_SK_LOOKUP] = "sk_lookup", | |
218 | [BPF_PROG_TYPE_SYSCALL] = "syscall", | |
d0fe92fb | 219 | [BPF_PROG_TYPE_NETFILTER] = "netfilter", |
d18616e7 DM |
220 | }; |
221 | ||
a8a1f7d0 SF |
222 | static int __base_pr(enum libbpf_print_level level, const char *format, |
223 | va_list args) | |
b3f59d66 | 224 | { |
6f1ae8b6 YS |
225 | if (level == LIBBPF_DEBUG) |
226 | return 0; | |
227 | ||
a8a1f7d0 | 228 | return vfprintf(stderr, format, args); |
b3f59d66 WN |
229 | } |
230 | ||
a8a1f7d0 | 231 | static libbpf_print_fn_t __libbpf_pr = __base_pr; |
b3f59d66 | 232 | |
e87fd8ba | 233 | libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn) |
b3f59d66 | 234 | { |
f1cb927c JK |
235 | libbpf_print_fn_t old_print_fn; |
236 | ||
237 | old_print_fn = __atomic_exchange_n(&__libbpf_pr, fn, __ATOMIC_RELAXED); | |
e87fd8ba | 238 | |
e87fd8ba | 239 | return old_print_fn; |
b3f59d66 | 240 | } |
1a5e3fb1 | 241 | |
8461ef8b YS |
242 | __printf(2, 3) |
243 | void libbpf_print(enum libbpf_print_level level, const char *format, ...) | |
244 | { | |
245 | va_list args; | |
d7c5802f | 246 | int old_errno; |
f1cb927c | 247 | libbpf_print_fn_t print_fn; |
8461ef8b | 248 | |
f1cb927c JK |
249 | print_fn = __atomic_load_n(&__libbpf_pr, __ATOMIC_RELAXED); |
250 | if (!print_fn) | |
6f1ae8b6 YS |
251 | return; |
252 | ||
d7c5802f AN |
253 | old_errno = errno; |
254 | ||
8461ef8b | 255 | va_start(args, format); |
6f1ae8b6 | 256 | __libbpf_pr(level, format, args); |
8461ef8b | 257 | va_end(args); |
d7c5802f AN |
258 | |
259 | errno = old_errno; | |
8461ef8b YS |
260 | } |
261 | ||
dc3a2d25 THJ |
262 | static void pr_perm_msg(int err) |
263 | { | |
264 | struct rlimit limit; | |
265 | char buf[100]; | |
266 | ||
267 | if (err != -EPERM || geteuid() != 0) | |
268 | return; | |
269 | ||
270 | err = getrlimit(RLIMIT_MEMLOCK, &limit); | |
271 | if (err) | |
272 | return; | |
273 | ||
274 | if (limit.rlim_cur == RLIM_INFINITY) | |
275 | return; | |
276 | ||
277 | if (limit.rlim_cur < 1024) | |
b5c7d0d0 | 278 | snprintf(buf, sizeof(buf), "%zu bytes", (size_t)limit.rlim_cur); |
dc3a2d25 THJ |
279 | else if (limit.rlim_cur < 1024*1024) |
280 | snprintf(buf, sizeof(buf), "%.1f KiB", (double)limit.rlim_cur / 1024); | |
281 | else | |
282 | snprintf(buf, sizeof(buf), "%.1f MiB", (double)limit.rlim_cur / (1024*1024)); | |
283 | ||
284 | pr_warn("permission error while running as root; try raising 'ulimit -l'? current value: %s\n", | |
285 | buf); | |
286 | } | |
287 | ||
6371ca3b WN |
288 | #define STRERR_BUFSIZE 128 |
289 | ||
1a5e3fb1 WN |
290 | /* Copied from tools/perf/util/util.h */ |
291 | #ifndef zfree | |
292 | # define zfree(ptr) ({ free(*ptr); *ptr = NULL; }) | |
293 | #endif | |
294 | ||
295 | #ifndef zclose | |
296 | # define zclose(fd) ({ \ | |
297 | int ___err = 0; \ | |
298 | if ((fd) >= 0) \ | |
299 | ___err = close((fd)); \ | |
300 | fd = -1; \ | |
301 | ___err; }) | |
302 | #endif | |
303 | ||
34be1646 SL |
304 | static inline __u64 ptr_to_u64(const void *ptr) |
305 | { | |
306 | return (__u64) (unsigned long) ptr; | |
307 | } | |
308 | ||
5981881d AN |
309 | int libbpf_set_strict_mode(enum libbpf_strict_mode mode) |
310 | { | |
bd054102 | 311 | /* as of v1.0 libbpf_set_strict_mode() is a no-op */ |
5981881d AN |
312 | return 0; |
313 | } | |
314 | ||
7615209f AN |
315 | __u32 libbpf_major_version(void) |
316 | { | |
317 | return LIBBPF_MAJOR_VERSION; | |
318 | } | |
319 | ||
320 | __u32 libbpf_minor_version(void) | |
321 | { | |
322 | return LIBBPF_MINOR_VERSION; | |
323 | } | |
324 | ||
325 | const char *libbpf_version_string(void) | |
326 | { | |
327 | #define __S(X) #X | |
328 | #define _S(X) __S(X) | |
329 | return "v" _S(LIBBPF_MAJOR_VERSION) "." _S(LIBBPF_MINOR_VERSION); | |
330 | #undef _S | |
331 | #undef __S | |
332 | } | |
333 | ||
166750bc AN |
334 | enum reloc_type { |
335 | RELO_LD64, | |
336 | RELO_CALL, | |
337 | RELO_DATA, | |
a18f7214 AS |
338 | RELO_EXTERN_LD64, |
339 | RELO_EXTERN_CALL, | |
53eddb5e | 340 | RELO_SUBPROG_ADDR, |
d0e92887 | 341 | RELO_CORE, |
166750bc AN |
342 | }; |
343 | ||
344 | struct reloc_desc { | |
345 | enum reloc_type type; | |
346 | int insn_idx; | |
d0e92887 AS |
347 | union { |
348 | const struct bpf_core_relo *core_relo; /* used when type == RELO_CORE */ | |
349 | struct { | |
350 | int map_idx; | |
351 | int sym_off; | |
3055ddd6 | 352 | int ext_idx; |
d0e92887 AS |
353 | }; |
354 | }; | |
166750bc AN |
355 | }; |
356 | ||
15ea31fa AN |
357 | /* stored as sec_def->cookie for all libbpf-supported SEC()s */ |
358 | enum sec_def_flags { | |
359 | SEC_NONE = 0, | |
360 | /* expected_attach_type is optional, if kernel doesn't support that */ | |
361 | SEC_EXP_ATTACH_OPT = 1, | |
362 | /* legacy, only used by libbpf_get_type_names() and | |
363 | * libbpf_attach_type_by_name(), not used by libbpf itself at all. | |
364 | * This used to be associated with cgroup (and few other) BPF programs | |
365 | * that were attachable through BPF_PROG_ATTACH command. Pretty | |
366 | * meaningless nowadays, though. | |
367 | */ | |
368 | SEC_ATTACHABLE = 2, | |
369 | SEC_ATTACHABLE_OPT = SEC_ATTACHABLE | SEC_EXP_ATTACH_OPT, | |
370 | /* attachment target is specified through BTF ID in either kernel or | |
e3ba8e4e KM |
371 | * other BPF program's BTF object |
372 | */ | |
15ea31fa AN |
373 | SEC_ATTACH_BTF = 4, |
374 | /* BPF program type allows sleeping/blocking in kernel */ | |
375 | SEC_SLEEPABLE = 8, | |
082c4bfb | 376 | /* BPF program support non-linear XDP buffer */ |
450b167f | 377 | SEC_XDP_FRAGS = 16, |
5902da6d JO |
378 | /* Setup proper attach type for usdt probes. */ |
379 | SEC_USDT = 32, | |
15ea31fa AN |
380 | }; |
381 | ||
25498a19 | 382 | struct bpf_sec_def { |
697f104d | 383 | char *sec; |
25498a19 AN |
384 | enum bpf_prog_type prog_type; |
385 | enum bpf_attach_type expected_attach_type; | |
15ea31fa | 386 | long cookie; |
697f104d | 387 | int handler_id; |
12d9466d | 388 | |
4fa5bcfe AN |
389 | libbpf_prog_setup_fn_t prog_setup_fn; |
390 | libbpf_prog_prepare_load_fn_t prog_prepare_load_fn; | |
391 | libbpf_prog_attach_fn_t prog_attach_fn; | |
25498a19 AN |
392 | }; |
393 | ||
a5b8bd47 WN |
394 | /* |
395 | * bpf_prog should be a better name but it has been used in | |
396 | * linux/filter.h. | |
397 | */ | |
398 | struct bpf_program { | |
bd054102 | 399 | char *name; |
52109584 | 400 | char *sec_name; |
c1122392 | 401 | size_t sec_idx; |
bd054102 | 402 | const struct bpf_sec_def *sec_def; |
c1122392 AN |
403 | /* this program's instruction offset (in number of instructions) |
404 | * within its containing ELF section | |
405 | */ | |
406 | size_t sec_insn_off; | |
407 | /* number of original instructions in ELF section belonging to this | |
408 | * program, not taking into account subprogram instructions possible | |
409 | * appended later during relocation | |
410 | */ | |
411 | size_t sec_insn_cnt; | |
412 | /* Offset (in number of instructions) of the start of instruction | |
413 | * belonging to this BPF program within its containing main BPF | |
414 | * program. For the entry-point (main) BPF program, this is always | |
415 | * zero. For a sub-program, this gets reset before each of main BPF | |
416 | * programs are processed and relocated and is used to determined | |
417 | * whether sub-program was already appended to the main program, and | |
418 | * if yes, at which instruction offset. | |
419 | */ | |
420 | size_t sub_insn_off; | |
421 | ||
c1122392 AN |
422 | /* instructions that belong to BPF program; insns[0] is located at |
423 | * sec_insn_off instruction within its ELF section in ELF file, so | |
424 | * when mapping ELF file instruction index to the local instruction, | |
425 | * one needs to subtract sec_insn_off; and vice versa. | |
426 | */ | |
a5b8bd47 | 427 | struct bpf_insn *insns; |
c1122392 AN |
428 | /* actual number of instruction in this BPF program's image; for |
429 | * entry-point BPF programs this includes the size of main program | |
430 | * itself plus all the used sub-programs, appended at the end | |
431 | */ | |
c3c55696 | 432 | size_t insns_cnt; |
34090915 | 433 | |
166750bc | 434 | struct reloc_desc *reloc_desc; |
34090915 | 435 | int nr_reloc; |
b3ce9079 AN |
436 | |
437 | /* BPF verifier log settings */ | |
438 | char *log_buf; | |
439 | size_t log_size; | |
440 | __u32 log_level; | |
55cffde2 | 441 | |
aa9b1ac3 | 442 | struct bpf_object *obj; |
d7be143b | 443 | |
cf90a20d | 444 | int fd; |
a3820c48 | 445 | bool autoload; |
43cb8cba | 446 | bool autoattach; |
7e2925f6 | 447 | bool sym_global; |
aea28a60 | 448 | bool mark_btf_static; |
c1122392 | 449 | enum bpf_prog_type type; |
d7be143b | 450 | enum bpf_attach_type expected_attach_type; |
7e2925f6 | 451 | int exception_cb_idx; |
cf90a20d | 452 | |
c1122392 | 453 | int prog_ifindex; |
91abb4a6 | 454 | __u32 attach_btf_obj_fd; |
12a8654b | 455 | __u32 attach_btf_id; |
e7bf94db | 456 | __u32 attach_prog_fd; |
cf90a20d | 457 | |
2993e051 YS |
458 | void *func_info; |
459 | __u32 func_info_rec_size; | |
f0187f0b | 460 | __u32 func_info_cnt; |
47eff617 | 461 | |
3d650141 MKL |
462 | void *line_info; |
463 | __u32 line_info_rec_size; | |
464 | __u32 line_info_cnt; | |
04656198 | 465 | __u32 prog_flags; |
a5b8bd47 WN |
466 | }; |
467 | ||
590a0088 MKL |
468 | struct bpf_struct_ops { |
469 | const char *tname; | |
470 | const struct btf_type *type; | |
471 | struct bpf_program **progs; | |
472 | __u32 *kern_func_off; | |
473 | /* e.g. struct tcp_congestion_ops in bpf_prog's btf format */ | |
474 | void *data; | |
475 | /* e.g. struct bpf_struct_ops_tcp_congestion_ops in | |
476 | * btf_vmlinux's format. | |
477 | * struct bpf_struct_ops_tcp_congestion_ops { | |
478 | * [... some other kernel fields ...] | |
479 | * struct tcp_congestion_ops data; | |
480 | * } | |
481 | * kern_vdata-size == sizeof(struct bpf_struct_ops_tcp_congestion_ops) | |
482 | * bpf_map__init_kern_struct_ops() will populate the "kern_vdata" | |
483 | * from "data". | |
484 | */ | |
485 | void *kern_vdata; | |
486 | __u32 type_id; | |
487 | }; | |
488 | ||
ac9d1389 AN |
489 | #define DATA_SEC ".data" |
490 | #define BSS_SEC ".bss" | |
491 | #define RODATA_SEC ".rodata" | |
81bfdd08 | 492 | #define KCONFIG_SEC ".kconfig" |
1c0c7074 | 493 | #define KSYMS_SEC ".ksyms" |
590a0088 | 494 | #define STRUCT_OPS_SEC ".struct_ops" |
809a69d6 | 495 | #define STRUCT_OPS_LINK_SEC ".struct_ops.link" |
ac9d1389 | 496 | |
d859900c DB |
497 | enum libbpf_map_type { |
498 | LIBBPF_MAP_UNSPEC, | |
499 | LIBBPF_MAP_DATA, | |
500 | LIBBPF_MAP_BSS, | |
501 | LIBBPF_MAP_RODATA, | |
81bfdd08 | 502 | LIBBPF_MAP_KCONFIG, |
d859900c DB |
503 | }; |
504 | ||
146bf811 AN |
505 | struct bpf_map_def { |
506 | unsigned int type; | |
507 | unsigned int key_size; | |
508 | unsigned int value_size; | |
509 | unsigned int max_entries; | |
510 | unsigned int map_flags; | |
511 | }; | |
512 | ||
9d759a9b | 513 | struct bpf_map { |
ec41817b | 514 | struct bpf_object *obj; |
561bbcca | 515 | char *name; |
aed65917 AN |
516 | /* real_name is defined for special internal maps (.rodata*, |
517 | * .data*, .bss, .kconfig) and preserves their original ELF section | |
e3ba8e4e | 518 | * name. This is important to be able to find corresponding BTF |
aed65917 AN |
519 | * DATASEC information. |
520 | */ | |
521 | char *real_name; | |
01af3bf0 | 522 | int fd; |
db48814b AN |
523 | int sec_idx; |
524 | size_t sec_offset; | |
f0307a7e | 525 | int map_ifindex; |
addb9fc9 | 526 | int inner_map_fd; |
9d759a9b | 527 | struct bpf_map_def def; |
1bdb6c9a | 528 | __u32 numa_node; |
646f02ff | 529 | __u32 btf_var_idx; |
5b891af7 MKL |
530 | __u32 btf_key_type_id; |
531 | __u32 btf_value_type_id; | |
590a0088 | 532 | __u32 btf_vmlinux_value_type_id; |
d859900c | 533 | enum libbpf_map_type libbpf_type; |
eba9c5f4 | 534 | void *mmaped; |
590a0088 | 535 | struct bpf_struct_ops *st_ops; |
646f02ff AN |
536 | struct bpf_map *inner_map; |
537 | void **init_slots; | |
538 | int init_slots_sz; | |
4580b25f THJ |
539 | char *pin_path; |
540 | bool pinned; | |
ec6d5f47 | 541 | bool reused; |
ec41817b | 542 | bool autocreate; |
47512102 | 543 | __u64 map_extra; |
d859900c DB |
544 | }; |
545 | ||
166750bc AN |
546 | enum extern_type { |
547 | EXT_UNKNOWN, | |
2e33efe3 | 548 | EXT_KCFG, |
1c0c7074 | 549 | EXT_KSYM, |
2e33efe3 AN |
550 | }; |
551 | ||
552 | enum kcfg_type { | |
553 | KCFG_UNKNOWN, | |
554 | KCFG_CHAR, | |
555 | KCFG_BOOL, | |
556 | KCFG_INT, | |
557 | KCFG_TRISTATE, | |
558 | KCFG_CHAR_ARR, | |
166750bc AN |
559 | }; |
560 | ||
561 | struct extern_desc { | |
2e33efe3 | 562 | enum extern_type type; |
166750bc AN |
563 | int sym_idx; |
564 | int btf_id; | |
2e33efe3 AN |
565 | int sec_btf_id; |
566 | const char *name; | |
5964a223 | 567 | char *essent_name; |
166750bc | 568 | bool is_set; |
2e33efe3 AN |
569 | bool is_weak; |
570 | union { | |
571 | struct { | |
572 | enum kcfg_type type; | |
573 | int sz; | |
574 | int align; | |
575 | int data_off; | |
576 | bool is_signed; | |
577 | } kcfg; | |
1c0c7074 AN |
578 | struct { |
579 | unsigned long long addr; | |
d370bbe1 HL |
580 | |
581 | /* target btf_id of the corresponding kernel var. */ | |
284d2587 AN |
582 | int kernel_btf_obj_fd; |
583 | int kernel_btf_id; | |
d370bbe1 HL |
584 | |
585 | /* local btf_id of the ksym extern's type. */ | |
586 | __u32 type_id; | |
9dbe6015 KKD |
587 | /* BTF fd index to be patched in for insn->off, this is |
588 | * 0 for vmlinux BTF, index in obj->fd_array for module | |
589 | * BTF | |
590 | */ | |
591 | __s16 btf_fd_idx; | |
1c0c7074 | 592 | } ksym; |
2e33efe3 | 593 | }; |
166750bc AN |
594 | }; |
595 | ||
4f33a53d AN |
596 | struct module_btf { |
597 | struct btf *btf; | |
598 | char *name; | |
599 | __u32 id; | |
91abb4a6 | 600 | int fd; |
9dbe6015 | 601 | int fd_array_idx; |
4f33a53d AN |
602 | }; |
603 | ||
25bbbd7a AN |
604 | enum sec_type { |
605 | SEC_UNUSED = 0, | |
606 | SEC_RELO, | |
607 | SEC_BSS, | |
608 | SEC_DATA, | |
609 | SEC_RODATA, | |
610 | }; | |
611 | ||
612 | struct elf_sec_desc { | |
613 | enum sec_type sec_type; | |
614 | Elf64_Shdr *shdr; | |
615 | Elf_Data *data; | |
616 | }; | |
617 | ||
29a30ff5 AN |
618 | struct elf_state { |
619 | int fd; | |
620 | const void *obj_buf; | |
621 | size_t obj_buf_sz; | |
622 | Elf *elf; | |
ad23b723 | 623 | Elf64_Ehdr *ehdr; |
29a30ff5 | 624 | Elf_Data *symbols; |
29a30ff5 | 625 | Elf_Data *st_ops_data; |
809a69d6 | 626 | Elf_Data *st_ops_link_data; |
29a30ff5 AN |
627 | size_t shstrndx; /* section index for section name strings */ |
628 | size_t strtabidx; | |
25bbbd7a | 629 | struct elf_sec_desc *secs; |
51deedc9 | 630 | size_t sec_cnt; |
29a30ff5 AN |
631 | int btf_maps_shndx; |
632 | __u32 btf_maps_sec_btf_id; | |
633 | int text_shndx; | |
634 | int symbols_shndx; | |
29a30ff5 | 635 | int st_ops_shndx; |
809a69d6 | 636 | int st_ops_link_shndx; |
4f33a53d AN |
637 | }; |
638 | ||
2e4913e0 AN |
639 | struct usdt_manager; |
640 | ||
1a5e3fb1 | 641 | struct bpf_object { |
d859900c | 642 | char name[BPF_OBJ_NAME_LEN]; |
cb1e5e96 | 643 | char license[64]; |
438363c0 | 644 | __u32 kern_version; |
0b3d1efa | 645 | |
a5b8bd47 WN |
646 | struct bpf_program *programs; |
647 | size_t nr_programs; | |
9d759a9b WN |
648 | struct bpf_map *maps; |
649 | size_t nr_maps; | |
bf829271 | 650 | size_t maps_cap; |
9d759a9b | 651 | |
8601fd42 | 652 | char *kconfig; |
166750bc AN |
653 | struct extern_desc *externs; |
654 | int nr_extern; | |
81bfdd08 | 655 | int kconfig_map_idx; |
166750bc | 656 | |
52d3352e | 657 | bool loaded; |
c3c55696 | 658 | bool has_subcalls; |
25bbbd7a | 659 | bool has_rodata; |
a5b8bd47 | 660 | |
e2fa0156 AS |
661 | struct bpf_gen *gen_loader; |
662 | ||
29a30ff5 AN |
663 | /* Information when doing ELF related work. Only valid if efile.elf is not NULL */ |
664 | struct elf_state efile; | |
10931d24 | 665 | |
8a138aed | 666 | struct btf *btf; |
0f7515ca AN |
667 | struct btf_ext *btf_ext; |
668 | ||
a6ed02ca KS |
669 | /* Parse and load BTF vmlinux if any of the programs in the object need |
670 | * it at load time. | |
671 | */ | |
672 | struct btf *btf_vmlinux; | |
1373ff59 SC |
673 | /* Path to the custom BTF to be used for BPF CO-RE relocations as an |
674 | * override for vmlinux BTF. | |
675 | */ | |
676 | char *btf_custom_path; | |
0f7515ca AN |
677 | /* vmlinux BTF override for CO-RE relocations */ |
678 | struct btf *btf_vmlinux_override; | |
4f33a53d AN |
679 | /* Lazily initialized kernel module BTFs */ |
680 | struct module_btf *btf_modules; | |
681 | bool btf_modules_loaded; | |
682 | size_t btf_module_cnt; | |
683 | size_t btf_module_cap; | |
8a138aed | 684 | |
e0e3ea88 AN |
685 | /* optional log settings passed to BPF_BTF_LOAD and BPF_PROG_LOAD commands */ |
686 | char *log_buf; | |
687 | size_t log_size; | |
688 | __u32 log_level; | |
689 | ||
9dbe6015 KKD |
690 | int *fd_array; |
691 | size_t fd_array_cap; | |
692 | size_t fd_array_cnt; | |
693 | ||
2e4913e0 AN |
694 | struct usdt_manager *usdt_man; |
695 | ||
1a5e3fb1 WN |
696 | char path[]; |
697 | }; | |
1a5e3fb1 | 698 | |
88a82120 AN |
699 | static const char *elf_sym_str(const struct bpf_object *obj, size_t off); |
700 | static const char *elf_sec_str(const struct bpf_object *obj, size_t off); | |
701 | static Elf_Scn *elf_sec_by_idx(const struct bpf_object *obj, size_t idx); | |
702 | static Elf_Scn *elf_sec_by_name(const struct bpf_object *obj, const char *name); | |
ad23b723 | 703 | static Elf64_Shdr *elf_sec_hdr(const struct bpf_object *obj, Elf_Scn *scn); |
88a82120 AN |
704 | static const char *elf_sec_name(const struct bpf_object *obj, Elf_Scn *scn); |
705 | static Elf_Data *elf_sec_data(const struct bpf_object *obj, Elf_Scn *scn); | |
ad23b723 AN |
706 | static Elf64_Sym *elf_sym_by_idx(const struct bpf_object *obj, size_t idx); |
707 | static Elf64_Rel *elf_rel_by_idx(Elf_Data *data, size_t idx); | |
88a82120 | 708 | |
29cd77f4 | 709 | void bpf_program__unload(struct bpf_program *prog) |
55cffde2 WN |
710 | { |
711 | if (!prog) | |
712 | return; | |
713 | ||
cf90a20d | 714 | zclose(prog->fd); |
2993e051 | 715 | |
2993e051 | 716 | zfree(&prog->func_info); |
07a09d1b | 717 | zfree(&prog->line_info); |
55cffde2 WN |
718 | } |
719 | ||
a5b8bd47 WN |
720 | static void bpf_program__exit(struct bpf_program *prog) |
721 | { | |
722 | if (!prog) | |
723 | return; | |
724 | ||
55cffde2 | 725 | bpf_program__unload(prog); |
88cda1c9 | 726 | zfree(&prog->name); |
52109584 | 727 | zfree(&prog->sec_name); |
a5b8bd47 | 728 | zfree(&prog->insns); |
34090915 WN |
729 | zfree(&prog->reloc_desc); |
730 | ||
731 | prog->nr_reloc = 0; | |
a5b8bd47 | 732 | prog->insns_cnt = 0; |
c1122392 | 733 | prog->sec_idx = -1; |
a5b8bd47 WN |
734 | } |
735 | ||
c3c55696 AN |
736 | static bool insn_is_subprog_call(const struct bpf_insn *insn) |
737 | { | |
738 | return BPF_CLASS(insn->code) == BPF_JMP && | |
739 | BPF_OP(insn->code) == BPF_CALL && | |
740 | BPF_SRC(insn->code) == BPF_K && | |
741 | insn->src_reg == BPF_PSEUDO_CALL && | |
742 | insn->dst_reg == 0 && | |
743 | insn->off == 0; | |
744 | } | |
745 | ||
aa0b8d43 MKL |
746 | static bool is_call_insn(const struct bpf_insn *insn) |
747 | { | |
748 | return insn->code == (BPF_JMP | BPF_CALL); | |
749 | } | |
750 | ||
53eddb5e YS |
751 | static bool insn_is_pseudo_func(struct bpf_insn *insn) |
752 | { | |
aa0b8d43 | 753 | return is_ldimm64_insn(insn) && insn->src_reg == BPF_PSEUDO_FUNC; |
53eddb5e YS |
754 | } |
755 | ||
a5b8bd47 | 756 | static int |
c3c55696 AN |
757 | bpf_object__init_prog(struct bpf_object *obj, struct bpf_program *prog, |
758 | const char *name, size_t sec_idx, const char *sec_name, | |
759 | size_t sec_off, void *insn_data, size_t insn_data_sz) | |
a5b8bd47 | 760 | { |
c1122392 AN |
761 | if (insn_data_sz == 0 || insn_data_sz % BPF_INSN_SZ || sec_off % BPF_INSN_SZ) { |
762 | pr_warn("sec '%s': corrupted program '%s', offset %zu, size %zu\n", | |
763 | sec_name, name, sec_off, insn_data_sz); | |
a5b8bd47 WN |
764 | return -EINVAL; |
765 | } | |
766 | ||
1ad9cbb8 | 767 | memset(prog, 0, sizeof(*prog)); |
c3c55696 AN |
768 | prog->obj = obj; |
769 | ||
c1122392 AN |
770 | prog->sec_idx = sec_idx; |
771 | prog->sec_insn_off = sec_off / BPF_INSN_SZ; | |
772 | prog->sec_insn_cnt = insn_data_sz / BPF_INSN_SZ; | |
773 | /* insns_cnt can later be increased by appending used subprograms */ | |
774 | prog->insns_cnt = prog->sec_insn_cnt; | |
a5b8bd47 | 775 | |
c1122392 | 776 | prog->type = BPF_PROG_TYPE_UNSPEC; |
cf90a20d | 777 | prog->fd = -1; |
7e2925f6 | 778 | prog->exception_cb_idx = -1; |
a3820c48 AN |
779 | |
780 | /* libbpf's convention for SEC("?abc...") is that it's just like | |
781 | * SEC("abc...") but the corresponding bpf_program starts out with | |
782 | * autoload set to false. | |
783 | */ | |
784 | if (sec_name[0] == '?') { | |
785 | prog->autoload = false; | |
786 | /* from now on forget there was ? in section name */ | |
787 | sec_name++; | |
788 | } else { | |
789 | prog->autoload = true; | |
790 | } | |
a5b8bd47 | 791 | |
43cb8cba HL |
792 | prog->autoattach = true; |
793 | ||
b3ce9079 AN |
794 | /* inherit object's log_level */ |
795 | prog->log_level = obj->log_level; | |
796 | ||
52109584 AN |
797 | prog->sec_name = strdup(sec_name); |
798 | if (!prog->sec_name) | |
c1122392 AN |
799 | goto errout; |
800 | ||
801 | prog->name = strdup(name); | |
802 | if (!prog->name) | |
a5b8bd47 | 803 | goto errout; |
a5b8bd47 | 804 | |
c1122392 AN |
805 | prog->insns = malloc(insn_data_sz); |
806 | if (!prog->insns) | |
a5b8bd47 | 807 | goto errout; |
c1122392 | 808 | memcpy(prog->insns, insn_data, insn_data_sz); |
a5b8bd47 WN |
809 | |
810 | return 0; | |
811 | errout: | |
c1122392 | 812 | pr_warn("sec '%s': failed to allocate memory for prog '%s'\n", sec_name, name); |
a5b8bd47 WN |
813 | bpf_program__exit(prog); |
814 | return -ENOMEM; | |
815 | } | |
816 | ||
817 | static int | |
c1122392 AN |
818 | bpf_object__add_programs(struct bpf_object *obj, Elf_Data *sec_data, |
819 | const char *sec_name, int sec_idx) | |
a5b8bd47 | 820 | { |
6245947c | 821 | Elf_Data *symbols = obj->efile.symbols; |
c1122392 AN |
822 | struct bpf_program *prog, *progs; |
823 | void *data = sec_data->d_buf; | |
6245947c AN |
824 | size_t sec_sz = sec_data->d_size, sec_off, prog_sz, nr_syms; |
825 | int nr_progs, err, i; | |
c1122392 | 826 | const char *name; |
ad23b723 | 827 | Elf64_Sym *sym; |
a5b8bd47 WN |
828 | |
829 | progs = obj->programs; | |
830 | nr_progs = obj->nr_programs; | |
ad23b723 | 831 | nr_syms = symbols->d_size / sizeof(Elf64_Sym); |
a5b8bd47 | 832 | |
6245947c | 833 | for (i = 0; i < nr_syms; i++) { |
ad23b723 AN |
834 | sym = elf_sym_by_idx(obj, i); |
835 | ||
836 | if (sym->st_shndx != sec_idx) | |
6245947c | 837 | continue; |
ad23b723 | 838 | if (ELF64_ST_TYPE(sym->st_info) != STT_FUNC) |
6245947c | 839 | continue; |
88cda1c9 | 840 | |
ad23b723 AN |
841 | prog_sz = sym->st_size; |
842 | sec_off = sym->st_value; | |
88cda1c9 | 843 | |
ad23b723 | 844 | name = elf_sym_str(obj, sym->st_name); |
c1122392 AN |
845 | if (!name) { |
846 | pr_warn("sec '%s': failed to get symbol name for offset %zu\n", | |
847 | sec_name, sec_off); | |
848 | return -LIBBPF_ERRNO__FORMAT; | |
849 | } | |
88cda1c9 | 850 | |
c1122392 AN |
851 | if (sec_off + prog_sz > sec_sz) { |
852 | pr_warn("sec '%s': program at offset %zu crosses section boundary\n", | |
853 | sec_name, sec_off); | |
854 | return -LIBBPF_ERRNO__FORMAT; | |
855 | } | |
88cda1c9 | 856 | |
ad23b723 | 857 | if (sec_idx != obj->efile.text_shndx && ELF64_ST_BIND(sym->st_info) == STB_LOCAL) { |
513f485c AN |
858 | pr_warn("sec '%s': program '%s' is static and not supported\n", sec_name, name); |
859 | return -ENOTSUP; | |
860 | } | |
861 | ||
c3c55696 AN |
862 | pr_debug("sec '%s': found program '%s' at insn offset %zu (%zu bytes), code size %zu insns (%zu bytes)\n", |
863 | sec_name, name, sec_off / BPF_INSN_SZ, sec_off, prog_sz / BPF_INSN_SZ, prog_sz); | |
88cda1c9 | 864 | |
c3c55696 | 865 | progs = libbpf_reallocarray(progs, nr_progs + 1, sizeof(*progs)); |
c1122392 AN |
866 | if (!progs) { |
867 | /* | |
868 | * In this case the original obj->programs | |
869 | * is still valid, so don't need special treat for | |
870 | * bpf_close_object(). | |
871 | */ | |
872 | pr_warn("sec '%s': failed to alloc memory for new program '%s'\n", | |
873 | sec_name, name); | |
874 | return -ENOMEM; | |
88cda1c9 | 875 | } |
c1122392 | 876 | obj->programs = progs; |
88cda1c9 | 877 | |
c1122392 | 878 | prog = &progs[nr_progs]; |
9a94f277 | 879 | |
c3c55696 AN |
880 | err = bpf_object__init_prog(obj, prog, name, sec_idx, sec_name, |
881 | sec_off, data + sec_off, prog_sz); | |
c1122392 AN |
882 | if (err) |
883 | return err; | |
9a94f277 | 884 | |
7e2925f6 KKD |
885 | if (ELF64_ST_BIND(sym->st_info) != STB_LOCAL) |
886 | prog->sym_global = true; | |
887 | ||
e5670fa0 AN |
888 | /* if function is a global/weak symbol, but has restricted |
889 | * (STV_HIDDEN or STV_INTERNAL) visibility, mark its BTF FUNC | |
890 | * as static to enable more permissive BPF verification mode | |
891 | * with more outside context available to BPF verifier | |
aea28a60 | 892 | */ |
7e2925f6 KKD |
893 | if (prog->sym_global && (ELF64_ST_VISIBILITY(sym->st_other) == STV_HIDDEN |
894 | || ELF64_ST_VISIBILITY(sym->st_other) == STV_INTERNAL)) | |
aea28a60 AN |
895 | prog->mark_btf_static = true; |
896 | ||
c1122392 AN |
897 | nr_progs++; |
898 | obj->nr_programs = nr_progs; | |
88cda1c9 MKL |
899 | } |
900 | ||
901 | return 0; | |
902 | } | |
903 | ||
590a0088 MKL |
904 | static const struct btf_member * |
905 | find_member_by_offset(const struct btf_type *t, __u32 bit_offset) | |
906 | { | |
907 | struct btf_member *m; | |
908 | int i; | |
909 | ||
910 | for (i = 0, m = btf_members(t); i < btf_vlen(t); i++, m++) { | |
911 | if (btf_member_bit_offset(t, i) == bit_offset) | |
912 | return m; | |
913 | } | |
914 | ||
915 | return NULL; | |
916 | } | |
917 | ||
918 | static const struct btf_member * | |
919 | find_member_by_name(const struct btf *btf, const struct btf_type *t, | |
920 | const char *name) | |
921 | { | |
922 | struct btf_member *m; | |
923 | int i; | |
924 | ||
925 | for (i = 0, m = btf_members(t); i < btf_vlen(t); i++, m++) { | |
926 | if (!strcmp(btf__name_by_offset(btf, m->name_off), name)) | |
927 | return m; | |
928 | } | |
929 | ||
930 | return NULL; | |
931 | } | |
932 | ||
933 | #define STRUCT_OPS_VALUE_PREFIX "bpf_struct_ops_" | |
a6ed02ca KS |
934 | static int find_btf_by_prefix_kind(const struct btf *btf, const char *prefix, |
935 | const char *name, __u32 kind); | |
590a0088 MKL |
936 | |
937 | static int | |
938 | find_struct_ops_kern_types(const struct btf *btf, const char *tname, | |
939 | const struct btf_type **type, __u32 *type_id, | |
940 | const struct btf_type **vtype, __u32 *vtype_id, | |
941 | const struct btf_member **data_member) | |
942 | { | |
943 | const struct btf_type *kern_type, *kern_vtype; | |
944 | const struct btf_member *kern_data_member; | |
945 | __s32 kern_vtype_id, kern_type_id; | |
590a0088 MKL |
946 | __u32 i; |
947 | ||
948 | kern_type_id = btf__find_by_name_kind(btf, tname, BTF_KIND_STRUCT); | |
949 | if (kern_type_id < 0) { | |
950 | pr_warn("struct_ops init_kern: struct %s is not found in kernel BTF\n", | |
951 | tname); | |
952 | return kern_type_id; | |
953 | } | |
954 | kern_type = btf__type_by_id(btf, kern_type_id); | |
955 | ||
956 | /* Find the corresponding "map_value" type that will be used | |
957 | * in map_update(BPF_MAP_TYPE_STRUCT_OPS). For example, | |
958 | * find "struct bpf_struct_ops_tcp_congestion_ops" from the | |
959 | * btf_vmlinux. | |
960 | */ | |
a6ed02ca KS |
961 | kern_vtype_id = find_btf_by_prefix_kind(btf, STRUCT_OPS_VALUE_PREFIX, |
962 | tname, BTF_KIND_STRUCT); | |
590a0088 | 963 | if (kern_vtype_id < 0) { |
a6ed02ca KS |
964 | pr_warn("struct_ops init_kern: struct %s%s is not found in kernel BTF\n", |
965 | STRUCT_OPS_VALUE_PREFIX, tname); | |
590a0088 MKL |
966 | return kern_vtype_id; |
967 | } | |
968 | kern_vtype = btf__type_by_id(btf, kern_vtype_id); | |
969 | ||
970 | /* Find "struct tcp_congestion_ops" from | |
971 | * struct bpf_struct_ops_tcp_congestion_ops { | |
972 | * [ ... ] | |
973 | * struct tcp_congestion_ops data; | |
974 | * } | |
975 | */ | |
976 | kern_data_member = btf_members(kern_vtype); | |
977 | for (i = 0; i < btf_vlen(kern_vtype); i++, kern_data_member++) { | |
978 | if (kern_data_member->type == kern_type_id) | |
979 | break; | |
980 | } | |
981 | if (i == btf_vlen(kern_vtype)) { | |
a6ed02ca KS |
982 | pr_warn("struct_ops init_kern: struct %s data is not found in struct %s%s\n", |
983 | tname, STRUCT_OPS_VALUE_PREFIX, tname); | |
590a0088 MKL |
984 | return -EINVAL; |
985 | } | |
986 | ||
987 | *type = kern_type; | |
988 | *type_id = kern_type_id; | |
989 | *vtype = kern_vtype; | |
990 | *vtype_id = kern_vtype_id; | |
991 | *data_member = kern_data_member; | |
992 | ||
993 | return 0; | |
994 | } | |
995 | ||
996 | static bool bpf_map__is_struct_ops(const struct bpf_map *map) | |
997 | { | |
998 | return map->def.type == BPF_MAP_TYPE_STRUCT_OPS; | |
999 | } | |
1000 | ||
1001 | /* Init the map's fields that depend on kern_btf */ | |
1002 | static int bpf_map__init_kern_struct_ops(struct bpf_map *map, | |
1003 | const struct btf *btf, | |
1004 | const struct btf *kern_btf) | |
1005 | { | |
1006 | const struct btf_member *member, *kern_member, *kern_data_member; | |
1007 | const struct btf_type *type, *kern_type, *kern_vtype; | |
1008 | __u32 i, kern_type_id, kern_vtype_id, kern_data_off; | |
1009 | struct bpf_struct_ops *st_ops; | |
1010 | void *data, *kern_data; | |
1011 | const char *tname; | |
1012 | int err; | |
1013 | ||
1014 | st_ops = map->st_ops; | |
1015 | type = st_ops->type; | |
1016 | tname = st_ops->tname; | |
1017 | err = find_struct_ops_kern_types(kern_btf, tname, | |
1018 | &kern_type, &kern_type_id, | |
1019 | &kern_vtype, &kern_vtype_id, | |
1020 | &kern_data_member); | |
1021 | if (err) | |
1022 | return err; | |
1023 | ||
1024 | pr_debug("struct_ops init_kern %s: type_id:%u kern_type_id:%u kern_vtype_id:%u\n", | |
1025 | map->name, st_ops->type_id, kern_type_id, kern_vtype_id); | |
1026 | ||
1027 | map->def.value_size = kern_vtype->size; | |
1028 | map->btf_vmlinux_value_type_id = kern_vtype_id; | |
1029 | ||
1030 | st_ops->kern_vdata = calloc(1, kern_vtype->size); | |
1031 | if (!st_ops->kern_vdata) | |
1032 | return -ENOMEM; | |
1033 | ||
1034 | data = st_ops->data; | |
1035 | kern_data_off = kern_data_member->offset / 8; | |
1036 | kern_data = st_ops->kern_vdata + kern_data_off; | |
1037 | ||
1038 | member = btf_members(type); | |
1039 | for (i = 0; i < btf_vlen(type); i++, member++) { | |
1040 | const struct btf_type *mtype, *kern_mtype; | |
1041 | __u32 mtype_id, kern_mtype_id; | |
1042 | void *mdata, *kern_mdata; | |
1043 | __s64 msize, kern_msize; | |
1044 | __u32 moff, kern_moff; | |
1045 | __u32 kern_member_idx; | |
1046 | const char *mname; | |
1047 | ||
1048 | mname = btf__name_by_offset(btf, member->name_off); | |
1049 | kern_member = find_member_by_name(kern_btf, kern_type, mname); | |
1050 | if (!kern_member) { | |
1051 | pr_warn("struct_ops init_kern %s: Cannot find member %s in kernel BTF\n", | |
1052 | map->name, mname); | |
1053 | return -ENOTSUP; | |
1054 | } | |
1055 | ||
1056 | kern_member_idx = kern_member - btf_members(kern_type); | |
1057 | if (btf_member_bitfield_size(type, i) || | |
1058 | btf_member_bitfield_size(kern_type, kern_member_idx)) { | |
1059 | pr_warn("struct_ops init_kern %s: bitfield %s is not supported\n", | |
1060 | map->name, mname); | |
1061 | return -ENOTSUP; | |
1062 | } | |
1063 | ||
1064 | moff = member->offset / 8; | |
1065 | kern_moff = kern_member->offset / 8; | |
1066 | ||
1067 | mdata = data + moff; | |
1068 | kern_mdata = kern_data + kern_moff; | |
1069 | ||
1070 | mtype = skip_mods_and_typedefs(btf, member->type, &mtype_id); | |
1071 | kern_mtype = skip_mods_and_typedefs(kern_btf, kern_member->type, | |
1072 | &kern_mtype_id); | |
1073 | if (BTF_INFO_KIND(mtype->info) != | |
1074 | BTF_INFO_KIND(kern_mtype->info)) { | |
1075 | pr_warn("struct_ops init_kern %s: Unmatched member type %s %u != %u(kernel)\n", | |
1076 | map->name, mname, BTF_INFO_KIND(mtype->info), | |
1077 | BTF_INFO_KIND(kern_mtype->info)); | |
1078 | return -ENOTSUP; | |
1079 | } | |
1080 | ||
1081 | if (btf_is_ptr(mtype)) { | |
1082 | struct bpf_program *prog; | |
1083 | ||
d2836ddd MKL |
1084 | prog = st_ops->progs[i]; |
1085 | if (!prog) | |
1086 | continue; | |
1087 | ||
590a0088 MKL |
1088 | kern_mtype = skip_mods_and_typedefs(kern_btf, |
1089 | kern_mtype->type, | |
1090 | &kern_mtype_id); | |
d2836ddd MKL |
1091 | |
1092 | /* mtype->type must be a func_proto which was | |
1093 | * guaranteed in bpf_object__collect_st_ops_relos(), | |
1094 | * so only check kern_mtype for func_proto here. | |
1095 | */ | |
1096 | if (!btf_is_func_proto(kern_mtype)) { | |
1097 | pr_warn("struct_ops init_kern %s: kernel member %s is not a func ptr\n", | |
590a0088 MKL |
1098 | map->name, mname); |
1099 | return -ENOTSUP; | |
1100 | } | |
1101 | ||
590a0088 MKL |
1102 | prog->attach_btf_id = kern_type_id; |
1103 | prog->expected_attach_type = kern_member_idx; | |
1104 | ||
1105 | st_ops->kern_func_off[i] = kern_data_off + kern_moff; | |
1106 | ||
1107 | pr_debug("struct_ops init_kern %s: func ptr %s is set to prog %s from data(+%u) to kern_data(+%u)\n", | |
1108 | map->name, mname, prog->name, moff, | |
1109 | kern_moff); | |
1110 | ||
1111 | continue; | |
1112 | } | |
1113 | ||
1114 | msize = btf__resolve_size(btf, mtype_id); | |
1115 | kern_msize = btf__resolve_size(kern_btf, kern_mtype_id); | |
1116 | if (msize < 0 || kern_msize < 0 || msize != kern_msize) { | |
1117 | pr_warn("struct_ops init_kern %s: Error in size of member %s: %zd != %zd(kernel)\n", | |
1118 | map->name, mname, (ssize_t)msize, | |
1119 | (ssize_t)kern_msize); | |
1120 | return -ENOTSUP; | |
1121 | } | |
1122 | ||
1123 | pr_debug("struct_ops init_kern %s: copy %s %u bytes from data(+%u) to kern_data(+%u)\n", | |
1124 | map->name, mname, (unsigned int)msize, | |
1125 | moff, kern_moff); | |
1126 | memcpy(kern_mdata, mdata, msize); | |
1127 | } | |
1128 | ||
1129 | return 0; | |
1130 | } | |
1131 | ||
1132 | static int bpf_object__init_kern_struct_ops_maps(struct bpf_object *obj) | |
1133 | { | |
590a0088 MKL |
1134 | struct bpf_map *map; |
1135 | size_t i; | |
1136 | int err; | |
1137 | ||
1138 | for (i = 0; i < obj->nr_maps; i++) { | |
1139 | map = &obj->maps[i]; | |
1140 | ||
1141 | if (!bpf_map__is_struct_ops(map)) | |
1142 | continue; | |
1143 | ||
a6ed02ca KS |
1144 | err = bpf_map__init_kern_struct_ops(map, obj->btf, |
1145 | obj->btf_vmlinux); | |
1146 | if (err) | |
590a0088 | 1147 | return err; |
590a0088 MKL |
1148 | } |
1149 | ||
590a0088 MKL |
1150 | return 0; |
1151 | } | |
1152 | ||
809a69d6 KFL |
1153 | static int init_struct_ops_maps(struct bpf_object *obj, const char *sec_name, |
1154 | int shndx, Elf_Data *data, __u32 map_flags) | |
590a0088 MKL |
1155 | { |
1156 | const struct btf_type *type, *datasec; | |
1157 | const struct btf_var_secinfo *vsi; | |
1158 | struct bpf_struct_ops *st_ops; | |
1159 | const char *tname, *var_name; | |
1160 | __s32 type_id, datasec_id; | |
1161 | const struct btf *btf; | |
1162 | struct bpf_map *map; | |
1163 | __u32 i; | |
1164 | ||
809a69d6 | 1165 | if (shndx == -1) |
590a0088 MKL |
1166 | return 0; |
1167 | ||
1168 | btf = obj->btf; | |
809a69d6 | 1169 | datasec_id = btf__find_by_name_kind(btf, sec_name, |
590a0088 MKL |
1170 | BTF_KIND_DATASEC); |
1171 | if (datasec_id < 0) { | |
1172 | pr_warn("struct_ops init: DATASEC %s not found\n", | |
809a69d6 | 1173 | sec_name); |
590a0088 MKL |
1174 | return -EINVAL; |
1175 | } | |
1176 | ||
1177 | datasec = btf__type_by_id(btf, datasec_id); | |
1178 | vsi = btf_var_secinfos(datasec); | |
1179 | for (i = 0; i < btf_vlen(datasec); i++, vsi++) { | |
1180 | type = btf__type_by_id(obj->btf, vsi->type); | |
1181 | var_name = btf__name_by_offset(obj->btf, type->name_off); | |
1182 | ||
1183 | type_id = btf__resolve_type(obj->btf, vsi->type); | |
1184 | if (type_id < 0) { | |
1185 | pr_warn("struct_ops init: Cannot resolve var type_id %u in DATASEC %s\n", | |
809a69d6 | 1186 | vsi->type, sec_name); |
590a0088 MKL |
1187 | return -EINVAL; |
1188 | } | |
1189 | ||
1190 | type = btf__type_by_id(obj->btf, type_id); | |
1191 | tname = btf__name_by_offset(obj->btf, type->name_off); | |
1192 | if (!tname[0]) { | |
1193 | pr_warn("struct_ops init: anonymous type is not supported\n"); | |
1194 | return -ENOTSUP; | |
1195 | } | |
1196 | if (!btf_is_struct(type)) { | |
1197 | pr_warn("struct_ops init: %s is not a struct\n", tname); | |
1198 | return -EINVAL; | |
1199 | } | |
1200 | ||
1201 | map = bpf_object__add_map(obj); | |
1202 | if (IS_ERR(map)) | |
1203 | return PTR_ERR(map); | |
1204 | ||
809a69d6 | 1205 | map->sec_idx = shndx; |
590a0088 MKL |
1206 | map->sec_offset = vsi->offset; |
1207 | map->name = strdup(var_name); | |
1208 | if (!map->name) | |
1209 | return -ENOMEM; | |
1210 | ||
1211 | map->def.type = BPF_MAP_TYPE_STRUCT_OPS; | |
1212 | map->def.key_size = sizeof(int); | |
1213 | map->def.value_size = type->size; | |
1214 | map->def.max_entries = 1; | |
809a69d6 | 1215 | map->def.map_flags = map_flags; |
590a0088 MKL |
1216 | |
1217 | map->st_ops = calloc(1, sizeof(*map->st_ops)); | |
1218 | if (!map->st_ops) | |
1219 | return -ENOMEM; | |
1220 | st_ops = map->st_ops; | |
1221 | st_ops->data = malloc(type->size); | |
1222 | st_ops->progs = calloc(btf_vlen(type), sizeof(*st_ops->progs)); | |
1223 | st_ops->kern_func_off = malloc(btf_vlen(type) * | |
1224 | sizeof(*st_ops->kern_func_off)); | |
1225 | if (!st_ops->data || !st_ops->progs || !st_ops->kern_func_off) | |
1226 | return -ENOMEM; | |
1227 | ||
809a69d6 | 1228 | if (vsi->offset + type->size > data->d_size) { |
590a0088 | 1229 | pr_warn("struct_ops init: var %s is beyond the end of DATASEC %s\n", |
809a69d6 | 1230 | var_name, sec_name); |
590a0088 MKL |
1231 | return -EINVAL; |
1232 | } | |
1233 | ||
1234 | memcpy(st_ops->data, | |
809a69d6 | 1235 | data->d_buf + vsi->offset, |
590a0088 MKL |
1236 | type->size); |
1237 | st_ops->tname = tname; | |
1238 | st_ops->type = type; | |
1239 | st_ops->type_id = type_id; | |
1240 | ||
1241 | pr_debug("struct_ops init: struct %s(type_id=%u) %s found at offset %u\n", | |
1242 | tname, type_id, var_name, vsi->offset); | |
1243 | } | |
1244 | ||
1245 | return 0; | |
1246 | } | |
1247 | ||
809a69d6 KFL |
1248 | static int bpf_object_init_struct_ops(struct bpf_object *obj) |
1249 | { | |
1250 | int err; | |
1251 | ||
1252 | err = init_struct_ops_maps(obj, STRUCT_OPS_SEC, obj->efile.st_ops_shndx, | |
1253 | obj->efile.st_ops_data, 0); | |
1254 | err = err ?: init_struct_ops_maps(obj, STRUCT_OPS_LINK_SEC, | |
1255 | obj->efile.st_ops_link_shndx, | |
1256 | obj->efile.st_ops_link_data, | |
1257 | BPF_F_LINK); | |
1258 | return err; | |
1259 | } | |
1260 | ||
6c956392 | 1261 | static struct bpf_object *bpf_object__new(const char *path, |
5e61f270 | 1262 | const void *obj_buf, |
2ce8450e AN |
1263 | size_t obj_buf_sz, |
1264 | const char *obj_name) | |
1a5e3fb1 WN |
1265 | { |
1266 | struct bpf_object *obj; | |
d859900c | 1267 | char *end; |
1a5e3fb1 WN |
1268 | |
1269 | obj = calloc(1, sizeof(struct bpf_object) + strlen(path) + 1); | |
1270 | if (!obj) { | |
be18010e | 1271 | pr_warn("alloc memory failed for %s\n", path); |
6371ca3b | 1272 | return ERR_PTR(-ENOMEM); |
1a5e3fb1 WN |
1273 | } |
1274 | ||
1275 | strcpy(obj->path, path); | |
2ce8450e | 1276 | if (obj_name) { |
9fc205b4 | 1277 | libbpf_strlcpy(obj->name, obj_name, sizeof(obj->name)); |
2ce8450e AN |
1278 | } else { |
1279 | /* Using basename() GNU version which doesn't modify arg. */ | |
9fc205b4 | 1280 | libbpf_strlcpy(obj->name, basename((void *)path), sizeof(obj->name)); |
2ce8450e AN |
1281 | end = strchr(obj->name, '.'); |
1282 | if (end) | |
1283 | *end = 0; | |
1284 | } | |
6c956392 | 1285 | |
d859900c | 1286 | obj->efile.fd = -1; |
6c956392 | 1287 | /* |
76e1022b | 1288 | * Caller of this function should also call |
6c956392 WN |
1289 | * bpf_object__elf_finish() after data collection to return |
1290 | * obj_buf to user. If not, we should duplicate the buffer to | |
1291 | * avoid user freeing them before elf finish. | |
1292 | */ | |
1293 | obj->efile.obj_buf = obj_buf; | |
1294 | obj->efile.obj_buf_sz = obj_buf_sz; | |
abd29c93 | 1295 | obj->efile.btf_maps_shndx = -1; |
590a0088 | 1296 | obj->efile.st_ops_shndx = -1; |
809a69d6 | 1297 | obj->efile.st_ops_link_shndx = -1; |
81bfdd08 | 1298 | obj->kconfig_map_idx = -1; |
6c956392 | 1299 | |
5e61f270 | 1300 | obj->kern_version = get_kernel_version(); |
52d3352e | 1301 | obj->loaded = false; |
9a208eff | 1302 | |
1a5e3fb1 WN |
1303 | return obj; |
1304 | } | |
1305 | ||
1306 | static void bpf_object__elf_finish(struct bpf_object *obj) | |
1307 | { | |
29a30ff5 | 1308 | if (!obj->efile.elf) |
1a5e3fb1 WN |
1309 | return; |
1310 | ||
b71a2ebf GC |
1311 | elf_end(obj->efile.elf); |
1312 | obj->efile.elf = NULL; | |
bec7d68c | 1313 | obj->efile.symbols = NULL; |
590a0088 | 1314 | obj->efile.st_ops_data = NULL; |
809a69d6 | 1315 | obj->efile.st_ops_link_data = NULL; |
b62f06e8 | 1316 | |
25bbbd7a AN |
1317 | zfree(&obj->efile.secs); |
1318 | obj->efile.sec_cnt = 0; | |
1a5e3fb1 | 1319 | zclose(obj->efile.fd); |
6c956392 WN |
1320 | obj->efile.obj_buf = NULL; |
1321 | obj->efile.obj_buf_sz = 0; | |
1a5e3fb1 WN |
1322 | } |
1323 | ||
1324 | static int bpf_object__elf_init(struct bpf_object *obj) | |
1325 | { | |
ad23b723 | 1326 | Elf64_Ehdr *ehdr; |
1a5e3fb1 | 1327 | int err = 0; |
ad23b723 | 1328 | Elf *elf; |
1a5e3fb1 | 1329 | |
29a30ff5 | 1330 | if (obj->efile.elf) { |
88a82120 | 1331 | pr_warn("elf: init internal error\n"); |
6371ca3b | 1332 | return -LIBBPF_ERRNO__LIBELF; |
1a5e3fb1 WN |
1333 | } |
1334 | ||
6c956392 | 1335 | if (obj->efile.obj_buf_sz > 0) { |
146bf811 | 1336 | /* obj_buf should have been validated by bpf_object__open_mem(). */ |
ad23b723 | 1337 | elf = elf_memory((char *)obj->efile.obj_buf, obj->efile.obj_buf_sz); |
6c956392 | 1338 | } else { |
92274e24 | 1339 | obj->efile.fd = open(obj->path, O_RDONLY | O_CLOEXEC); |
6c956392 | 1340 | if (obj->efile.fd < 0) { |
be5c5d4e | 1341 | char errmsg[STRERR_BUFSIZE], *cp; |
1ce6a9fc | 1342 | |
be5c5d4e AN |
1343 | err = -errno; |
1344 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
88a82120 | 1345 | pr_warn("elf: failed to open %s: %s\n", obj->path, cp); |
be5c5d4e | 1346 | return err; |
6c956392 WN |
1347 | } |
1348 | ||
ad23b723 | 1349 | elf = elf_begin(obj->efile.fd, ELF_C_READ_MMAP, NULL); |
1a5e3fb1 WN |
1350 | } |
1351 | ||
ad23b723 | 1352 | if (!elf) { |
88a82120 | 1353 | pr_warn("elf: failed to open %s as ELF file: %s\n", obj->path, elf_errmsg(-1)); |
6371ca3b | 1354 | err = -LIBBPF_ERRNO__LIBELF; |
1a5e3fb1 WN |
1355 | goto errout; |
1356 | } | |
1357 | ||
ad23b723 AN |
1358 | obj->efile.elf = elf; |
1359 | ||
1360 | if (elf_kind(elf) != ELF_K_ELF) { | |
1361 | err = -LIBBPF_ERRNO__FORMAT; | |
1362 | pr_warn("elf: '%s' is not a proper ELF object\n", obj->path); | |
1363 | goto errout; | |
1364 | } | |
1365 | ||
1366 | if (gelf_getclass(elf) != ELFCLASS64) { | |
1367 | err = -LIBBPF_ERRNO__FORMAT; | |
1368 | pr_warn("elf: '%s' is not a 64-bit ELF object\n", obj->path); | |
1369 | goto errout; | |
1370 | } | |
1371 | ||
1372 | obj->efile.ehdr = ehdr = elf64_getehdr(elf); | |
1373 | if (!obj->efile.ehdr) { | |
88a82120 | 1374 | pr_warn("elf: failed to get ELF header from %s: %s\n", obj->path, elf_errmsg(-1)); |
6371ca3b | 1375 | err = -LIBBPF_ERRNO__FORMAT; |
1a5e3fb1 WN |
1376 | goto errout; |
1377 | } | |
1a5e3fb1 | 1378 | |
ad23b723 | 1379 | if (elf_getshdrstrndx(elf, &obj->efile.shstrndx)) { |
88a82120 AN |
1380 | pr_warn("elf: failed to get section names section index for %s: %s\n", |
1381 | obj->path, elf_errmsg(-1)); | |
1382 | err = -LIBBPF_ERRNO__FORMAT; | |
1383 | goto errout; | |
1384 | } | |
1385 | ||
70e79866 | 1386 | /* ELF is corrupted/truncated, avoid calling elf_strptr. */ |
ad23b723 | 1387 | if (!elf_rawdata(elf_getscn(elf, obj->efile.shstrndx), NULL)) { |
88a82120 AN |
1388 | pr_warn("elf: failed to get section names strings from %s: %s\n", |
1389 | obj->path, elf_errmsg(-1)); | |
8f3f5792 NK |
1390 | err = -LIBBPF_ERRNO__FORMAT; |
1391 | goto errout; | |
88a82120 AN |
1392 | } |
1393 | ||
9b16137a | 1394 | /* Old LLVM set e_machine to EM_NONE */ |
ad23b723 | 1395 | if (ehdr->e_type != ET_REL || (ehdr->e_machine && ehdr->e_machine != EM_BPF)) { |
88a82120 | 1396 | pr_warn("elf: %s is not a valid eBPF object file\n", obj->path); |
6371ca3b | 1397 | err = -LIBBPF_ERRNO__FORMAT; |
1a5e3fb1 WN |
1398 | goto errout; |
1399 | } | |
1400 | ||
1401 | return 0; | |
1402 | errout: | |
1403 | bpf_object__elf_finish(obj); | |
1404 | return err; | |
1405 | } | |
1406 | ||
12ef5634 | 1407 | static int bpf_object__check_endianness(struct bpf_object *obj) |
cc4228d5 | 1408 | { |
3930198d | 1409 | #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ |
ad23b723 | 1410 | if (obj->efile.ehdr->e_ident[EI_DATA] == ELFDATA2LSB) |
12ef5634 | 1411 | return 0; |
3930198d | 1412 | #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ |
ad23b723 | 1413 | if (obj->efile.ehdr->e_ident[EI_DATA] == ELFDATA2MSB) |
12ef5634 AN |
1414 | return 0; |
1415 | #else | |
1416 | # error "Unrecognized __BYTE_ORDER__" | |
1417 | #endif | |
88a82120 | 1418 | pr_warn("elf: endianness mismatch in %s.\n", obj->path); |
6371ca3b | 1419 | return -LIBBPF_ERRNO__ENDIAN; |
cc4228d5 WN |
1420 | } |
1421 | ||
cb1e5e96 | 1422 | static int |
399dc65e | 1423 | bpf_object__init_license(struct bpf_object *obj, void *data, size_t size) |
cb1e5e96 | 1424 | { |
35a85550 SHY |
1425 | if (!data) { |
1426 | pr_warn("invalid license section in %s\n", obj->path); | |
1427 | return -LIBBPF_ERRNO__FORMAT; | |
1428 | } | |
f9798239 AN |
1429 | /* libbpf_strlcpy() only copies first N - 1 bytes, so size + 1 won't |
1430 | * go over allowed ELF data section buffer | |
1431 | */ | |
1432 | libbpf_strlcpy(obj->license, data, min(size + 1, sizeof(obj->license))); | |
cb1e5e96 WN |
1433 | pr_debug("license of %s is %s\n", obj->path, obj->license); |
1434 | return 0; | |
1435 | } | |
1436 | ||
54b8625c JF |
1437 | static int |
1438 | bpf_object__init_kversion(struct bpf_object *obj, void *data, size_t size) | |
1439 | { | |
1440 | __u32 kver; | |
1441 | ||
35a85550 | 1442 | if (!data || size != sizeof(kver)) { |
be18010e | 1443 | pr_warn("invalid kver section in %s\n", obj->path); |
54b8625c JF |
1444 | return -LIBBPF_ERRNO__FORMAT; |
1445 | } | |
1446 | memcpy(&kver, data, sizeof(kver)); | |
1447 | obj->kern_version = kver; | |
1448 | pr_debug("kernel version of %s is %x\n", obj->path, obj->kern_version); | |
1449 | return 0; | |
1450 | } | |
1451 | ||
addb9fc9 NS |
1452 | static bool bpf_map_type__is_map_in_map(enum bpf_map_type type) |
1453 | { | |
1454 | if (type == BPF_MAP_TYPE_ARRAY_OF_MAPS || | |
1455 | type == BPF_MAP_TYPE_HASH_OF_MAPS) | |
1456 | return true; | |
1457 | return false; | |
1458 | } | |
1459 | ||
b96c07f3 | 1460 | static int find_elf_sec_sz(const struct bpf_object *obj, const char *name, __u32 *size) |
1713d68b | 1461 | { |
25bbbd7a AN |
1462 | Elf_Data *data; |
1463 | Elf_Scn *scn; | |
1713d68b | 1464 | |
25bbbd7a | 1465 | if (!name) |
1713d68b | 1466 | return -EINVAL; |
88a82120 | 1467 | |
25bbbd7a AN |
1468 | scn = elf_sec_by_name(obj, name); |
1469 | data = elf_sec_data(obj, scn); | |
1470 | if (data) { | |
25bbbd7a | 1471 | *size = data->d_size; |
08894d9c | 1472 | return 0; /* found it */ |
1713d68b DB |
1473 | } |
1474 | ||
08894d9c | 1475 | return -ENOENT; |
1713d68b DB |
1476 | } |
1477 | ||
f33f742d | 1478 | static Elf64_Sym *find_elf_var_sym(const struct bpf_object *obj, const char *name) |
1713d68b DB |
1479 | { |
1480 | Elf_Data *symbols = obj->efile.symbols; | |
1481 | const char *sname; | |
1482 | size_t si; | |
1483 | ||
ad23b723 AN |
1484 | for (si = 0; si < symbols->d_size / sizeof(Elf64_Sym); si++) { |
1485 | Elf64_Sym *sym = elf_sym_by_idx(obj, si); | |
1713d68b | 1486 | |
3a06ec0a AN |
1487 | if (ELF64_ST_TYPE(sym->st_info) != STT_OBJECT) |
1488 | continue; | |
1489 | ||
1490 | if (ELF64_ST_BIND(sym->st_info) != STB_GLOBAL && | |
1491 | ELF64_ST_BIND(sym->st_info) != STB_WEAK) | |
1713d68b DB |
1492 | continue; |
1493 | ||
ad23b723 | 1494 | sname = elf_sym_str(obj, sym->st_name); |
1713d68b | 1495 | if (!sname) { |
ad23b723 | 1496 | pr_warn("failed to get sym name string for var %s\n", name); |
f33f742d | 1497 | return ERR_PTR(-EIO); |
1713d68b | 1498 | } |
f33f742d AN |
1499 | if (strcmp(name, sname) == 0) |
1500 | return sym; | |
1713d68b DB |
1501 | } |
1502 | ||
f33f742d | 1503 | return ERR_PTR(-ENOENT); |
1713d68b DB |
1504 | } |
1505 | ||
bf829271 | 1506 | static struct bpf_map *bpf_object__add_map(struct bpf_object *obj) |
d859900c | 1507 | { |
69721203 AN |
1508 | struct bpf_map *map; |
1509 | int err; | |
bf829271 | 1510 | |
69721203 AN |
1511 | err = libbpf_ensure_mem((void **)&obj->maps, &obj->maps_cap, |
1512 | sizeof(*obj->maps), obj->nr_maps + 1); | |
1513 | if (err) | |
1514 | return ERR_PTR(err); | |
bf829271 | 1515 | |
69721203 | 1516 | map = &obj->maps[obj->nr_maps++]; |
ec41817b | 1517 | map->obj = obj; |
69721203 AN |
1518 | map->fd = -1; |
1519 | map->inner_map_fd = -1; | |
ec41817b | 1520 | map->autocreate = true; |
bf829271 | 1521 | |
69721203 | 1522 | return map; |
d859900c DB |
1523 | } |
1524 | ||
9d0a2331 | 1525 | static size_t bpf_map_mmap_sz(unsigned int value_sz, unsigned int max_entries) |
eba9c5f4 | 1526 | { |
9d0a2331 | 1527 | const long page_sz = sysconf(_SC_PAGE_SIZE); |
eba9c5f4 AN |
1528 | size_t map_sz; |
1529 | ||
9d0a2331 | 1530 | map_sz = (size_t)roundup(value_sz, 8) * max_entries; |
eba9c5f4 AN |
1531 | map_sz = roundup(map_sz, page_sz); |
1532 | return map_sz; | |
1533 | } | |
1534 | ||
9d0a2331 JK |
1535 | static int bpf_map_mmap_resize(struct bpf_map *map, size_t old_sz, size_t new_sz) |
1536 | { | |
1537 | void *mmaped; | |
1538 | ||
1539 | if (!map->mmaped) | |
1540 | return -EINVAL; | |
1541 | ||
1542 | if (old_sz == new_sz) | |
1543 | return 0; | |
1544 | ||
1545 | mmaped = mmap(NULL, new_sz, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); | |
1546 | if (mmaped == MAP_FAILED) | |
1547 | return -errno; | |
1548 | ||
1549 | memcpy(mmaped, map->mmaped, min(old_sz, new_sz)); | |
1550 | munmap(map->mmaped, old_sz); | |
1551 | map->mmaped = mmaped; | |
1552 | return 0; | |
1553 | } | |
1554 | ||
aed65917 | 1555 | static char *internal_map_name(struct bpf_object *obj, const char *real_name) |
81bfdd08 | 1556 | { |
113e6b7e | 1557 | char map_name[BPF_OBJ_NAME_LEN], *p; |
aed65917 AN |
1558 | int pfx_len, sfx_len = max((size_t)7, strlen(real_name)); |
1559 | ||
1560 | /* This is one of the more confusing parts of libbpf for various | |
1561 | * reasons, some of which are historical. The original idea for naming | |
1562 | * internal names was to include as much of BPF object name prefix as | |
1563 | * possible, so that it can be distinguished from similar internal | |
1564 | * maps of a different BPF object. | |
1565 | * As an example, let's say we have bpf_object named 'my_object_name' | |
1566 | * and internal map corresponding to '.rodata' ELF section. The final | |
1567 | * map name advertised to user and to the kernel will be | |
1568 | * 'my_objec.rodata', taking first 8 characters of object name and | |
1569 | * entire 7 characters of '.rodata'. | |
1570 | * Somewhat confusingly, if internal map ELF section name is shorter | |
1571 | * than 7 characters, e.g., '.bss', we still reserve 7 characters | |
1572 | * for the suffix, even though we only have 4 actual characters, and | |
1573 | * resulting map will be called 'my_objec.bss', not even using all 15 | |
1574 | * characters allowed by the kernel. Oh well, at least the truncated | |
1575 | * object name is somewhat consistent in this case. But if the map | |
1576 | * name is '.kconfig', we'll still have entirety of '.kconfig' added | |
1577 | * (8 chars) and thus will be left with only first 7 characters of the | |
1578 | * object name ('my_obje'). Happy guessing, user, that the final map | |
1579 | * name will be "my_obje.kconfig". | |
1580 | * Now, with libbpf starting to support arbitrarily named .rodata.* | |
1581 | * and .data.* data sections, it's possible that ELF section name is | |
1582 | * longer than allowed 15 chars, so we now need to be careful to take | |
1583 | * only up to 15 first characters of ELF name, taking no BPF object | |
1584 | * name characters at all. So '.rodata.abracadabra' will result in | |
1585 | * '.rodata.abracad' kernel and user-visible name. | |
1586 | * We need to keep this convoluted logic intact for .data, .bss and | |
1587 | * .rodata maps, but for new custom .data.custom and .rodata.custom | |
1588 | * maps we use their ELF names as is, not prepending bpf_object name | |
1589 | * in front. We still need to truncate them to 15 characters for the | |
1590 | * kernel. Full name can be recovered for such maps by using DATASEC | |
1591 | * BTF type associated with such map's value type, though. | |
1592 | */ | |
1593 | if (sfx_len >= BPF_OBJ_NAME_LEN) | |
1594 | sfx_len = BPF_OBJ_NAME_LEN - 1; | |
1595 | ||
1596 | /* if there are two or more dots in map name, it's a custom dot map */ | |
1597 | if (strchr(real_name + 1, '.') != NULL) | |
1598 | pfx_len = 0; | |
1599 | else | |
1600 | pfx_len = min((size_t)BPF_OBJ_NAME_LEN - sfx_len - 1, strlen(obj->name)); | |
81bfdd08 AN |
1601 | |
1602 | snprintf(map_name, sizeof(map_name), "%.*s%.*s", pfx_len, obj->name, | |
aed65917 | 1603 | sfx_len, real_name); |
81bfdd08 | 1604 | |
113e6b7e THJ |
1605 | /* sanitise map name to characters allowed by kernel */ |
1606 | for (p = map_name; *p && p < map_name + sizeof(map_name); p++) | |
1607 | if (!isalnum(*p) && *p != '_' && *p != '.') | |
1608 | *p = '_'; | |
1609 | ||
81bfdd08 AN |
1610 | return strdup(map_name); |
1611 | } | |
1612 | ||
262cfb74 | 1613 | static int |
4fcac46c AN |
1614 | map_fill_btf_type_info(struct bpf_object *obj, struct bpf_map *map); |
1615 | ||
1616 | /* Internal BPF map is mmap()'able only if at least one of corresponding | |
1617 | * DATASEC's VARs are to be exposed through BPF skeleton. I.e., it's a GLOBAL | |
1618 | * variable and it's not marked as __hidden (which turns it into, effectively, | |
1619 | * a STATIC variable). | |
1620 | */ | |
1621 | static bool map_is_mmapable(struct bpf_object *obj, struct bpf_map *map) | |
1622 | { | |
1623 | const struct btf_type *t, *vt; | |
1624 | struct btf_var_secinfo *vsi; | |
1625 | int i, n; | |
1626 | ||
1627 | if (!map->btf_value_type_id) | |
1628 | return false; | |
1629 | ||
1630 | t = btf__type_by_id(obj->btf, map->btf_value_type_id); | |
1631 | if (!btf_is_datasec(t)) | |
1632 | return false; | |
1633 | ||
1634 | vsi = btf_var_secinfos(t); | |
1635 | for (i = 0, n = btf_vlen(t); i < n; i++, vsi++) { | |
1636 | vt = btf__type_by_id(obj->btf, vsi->type); | |
1637 | if (!btf_is_var(vt)) | |
1638 | continue; | |
1639 | ||
1640 | if (btf_var(vt)->linkage != BTF_VAR_STATIC) | |
1641 | return true; | |
1642 | } | |
1643 | ||
1644 | return false; | |
1645 | } | |
262cfb74 | 1646 | |
d859900c | 1647 | static int |
bf829271 | 1648 | bpf_object__init_internal_map(struct bpf_object *obj, enum libbpf_map_type type, |
aed65917 | 1649 | const char *real_name, int sec_idx, void *data, size_t data_sz) |
d859900c | 1650 | { |
bf829271 AN |
1651 | struct bpf_map_def *def; |
1652 | struct bpf_map *map; | |
9d0a2331 | 1653 | size_t mmap_sz; |
eba9c5f4 | 1654 | int err; |
bf829271 AN |
1655 | |
1656 | map = bpf_object__add_map(obj); | |
1657 | if (IS_ERR(map)) | |
1658 | return PTR_ERR(map); | |
d859900c DB |
1659 | |
1660 | map->libbpf_type = type; | |
db48814b AN |
1661 | map->sec_idx = sec_idx; |
1662 | map->sec_offset = 0; | |
aed65917 AN |
1663 | map->real_name = strdup(real_name); |
1664 | map->name = internal_map_name(obj, real_name); | |
1665 | if (!map->real_name || !map->name) { | |
1666 | zfree(&map->real_name); | |
1667 | zfree(&map->name); | |
d859900c DB |
1668 | return -ENOMEM; |
1669 | } | |
1670 | ||
bf829271 | 1671 | def = &map->def; |
d859900c DB |
1672 | def->type = BPF_MAP_TYPE_ARRAY; |
1673 | def->key_size = sizeof(int); | |
eba9c5f4 | 1674 | def->value_size = data_sz; |
d859900c | 1675 | def->max_entries = 1; |
81bfdd08 | 1676 | def->map_flags = type == LIBBPF_MAP_RODATA || type == LIBBPF_MAP_KCONFIG |
166750bc | 1677 | ? BPF_F_RDONLY_PROG : 0; |
4fcac46c AN |
1678 | |
1679 | /* failures are fine because of maps like .rodata.str1.1 */ | |
1680 | (void) map_fill_btf_type_info(obj, map); | |
1681 | ||
1682 | if (map_is_mmapable(obj, map)) | |
1683 | def->map_flags |= BPF_F_MMAPABLE; | |
7fe74b43 AN |
1684 | |
1685 | pr_debug("map '%s' (global data): at sec_idx %d, offset %zu, flags %x.\n", | |
81bfdd08 | 1686 | map->name, map->sec_idx, map->sec_offset, def->map_flags); |
7fe74b43 | 1687 | |
9d0a2331 JK |
1688 | mmap_sz = bpf_map_mmap_sz(map->def.value_size, map->def.max_entries); |
1689 | map->mmaped = mmap(NULL, mmap_sz, PROT_READ | PROT_WRITE, | |
eba9c5f4 AN |
1690 | MAP_SHARED | MAP_ANONYMOUS, -1, 0); |
1691 | if (map->mmaped == MAP_FAILED) { | |
1692 | err = -errno; | |
1693 | map->mmaped = NULL; | |
1694 | pr_warn("failed to alloc map '%s' content buffer: %d\n", | |
1695 | map->name, err); | |
aed65917 | 1696 | zfree(&map->real_name); |
eba9c5f4 AN |
1697 | zfree(&map->name); |
1698 | return err; | |
d859900c DB |
1699 | } |
1700 | ||
166750bc | 1701 | if (data) |
eba9c5f4 AN |
1702 | memcpy(map->mmaped, data, data_sz); |
1703 | ||
e1d1dc46 | 1704 | pr_debug("map %td is \"%s\"\n", map - obj->maps, map->name); |
d859900c DB |
1705 | return 0; |
1706 | } | |
1707 | ||
bf829271 AN |
1708 | static int bpf_object__init_global_data_maps(struct bpf_object *obj) |
1709 | { | |
25bbbd7a | 1710 | struct elf_sec_desc *sec_desc; |
aed65917 | 1711 | const char *sec_name; |
25bbbd7a | 1712 | int err = 0, sec_idx; |
bf829271 | 1713 | |
bf829271 AN |
1714 | /* |
1715 | * Populate obj->maps with libbpf internal maps. | |
1716 | */ | |
25bbbd7a AN |
1717 | for (sec_idx = 1; sec_idx < obj->efile.sec_cnt; sec_idx++) { |
1718 | sec_desc = &obj->efile.secs[sec_idx]; | |
1719 | ||
47ea7417 | 1720 | /* Skip recognized sections with size 0. */ |
d4e6d684 | 1721 | if (!sec_desc->data || sec_desc->data->d_size == 0) |
47ea7417 JH |
1722 | continue; |
1723 | ||
25bbbd7a AN |
1724 | switch (sec_desc->sec_type) { |
1725 | case SEC_DATA: | |
aed65917 | 1726 | sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, sec_idx)); |
25bbbd7a | 1727 | err = bpf_object__init_internal_map(obj, LIBBPF_MAP_DATA, |
aed65917 | 1728 | sec_name, sec_idx, |
25bbbd7a AN |
1729 | sec_desc->data->d_buf, |
1730 | sec_desc->data->d_size); | |
1731 | break; | |
1732 | case SEC_RODATA: | |
1733 | obj->has_rodata = true; | |
aed65917 | 1734 | sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, sec_idx)); |
25bbbd7a | 1735 | err = bpf_object__init_internal_map(obj, LIBBPF_MAP_RODATA, |
aed65917 | 1736 | sec_name, sec_idx, |
25bbbd7a AN |
1737 | sec_desc->data->d_buf, |
1738 | sec_desc->data->d_size); | |
1739 | break; | |
1740 | case SEC_BSS: | |
aed65917 | 1741 | sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, sec_idx)); |
25bbbd7a | 1742 | err = bpf_object__init_internal_map(obj, LIBBPF_MAP_BSS, |
aed65917 | 1743 | sec_name, sec_idx, |
25bbbd7a AN |
1744 | NULL, |
1745 | sec_desc->data->d_size); | |
1746 | break; | |
1747 | default: | |
1748 | /* skip */ | |
1749 | break; | |
1750 | } | |
bf829271 AN |
1751 | if (err) |
1752 | return err; | |
1753 | } | |
1754 | return 0; | |
1755 | } | |
1756 | ||
166750bc AN |
1757 | |
1758 | static struct extern_desc *find_extern_by_name(const struct bpf_object *obj, | |
1759 | const void *name) | |
1760 | { | |
1761 | int i; | |
1762 | ||
1763 | for (i = 0; i < obj->nr_extern; i++) { | |
1764 | if (strcmp(obj->externs[i].name, name) == 0) | |
1765 | return &obj->externs[i]; | |
1766 | } | |
1767 | return NULL; | |
1768 | } | |
1769 | ||
2e33efe3 AN |
1770 | static int set_kcfg_value_tri(struct extern_desc *ext, void *ext_val, |
1771 | char value) | |
166750bc | 1772 | { |
2e33efe3 AN |
1773 | switch (ext->kcfg.type) { |
1774 | case KCFG_BOOL: | |
166750bc | 1775 | if (value == 'm') { |
55d00c37 | 1776 | pr_warn("extern (kcfg) '%s': value '%c' implies tristate or char type\n", |
166750bc AN |
1777 | ext->name, value); |
1778 | return -EINVAL; | |
1779 | } | |
1780 | *(bool *)ext_val = value == 'y' ? true : false; | |
1781 | break; | |
2e33efe3 | 1782 | case KCFG_TRISTATE: |
166750bc AN |
1783 | if (value == 'y') |
1784 | *(enum libbpf_tristate *)ext_val = TRI_YES; | |
1785 | else if (value == 'm') | |
1786 | *(enum libbpf_tristate *)ext_val = TRI_MODULE; | |
1787 | else /* value == 'n' */ | |
1788 | *(enum libbpf_tristate *)ext_val = TRI_NO; | |
1789 | break; | |
2e33efe3 | 1790 | case KCFG_CHAR: |
166750bc AN |
1791 | *(char *)ext_val = value; |
1792 | break; | |
2e33efe3 AN |
1793 | case KCFG_UNKNOWN: |
1794 | case KCFG_INT: | |
1795 | case KCFG_CHAR_ARR: | |
166750bc | 1796 | default: |
55d00c37 | 1797 | pr_warn("extern (kcfg) '%s': value '%c' implies bool, tristate, or char type\n", |
166750bc AN |
1798 | ext->name, value); |
1799 | return -EINVAL; | |
1800 | } | |
1801 | ext->is_set = true; | |
1802 | return 0; | |
1803 | } | |
1804 | ||
2e33efe3 AN |
1805 | static int set_kcfg_value_str(struct extern_desc *ext, char *ext_val, |
1806 | const char *value) | |
166750bc AN |
1807 | { |
1808 | size_t len; | |
1809 | ||
2e33efe3 | 1810 | if (ext->kcfg.type != KCFG_CHAR_ARR) { |
55d00c37 AN |
1811 | pr_warn("extern (kcfg) '%s': value '%s' implies char array type\n", |
1812 | ext->name, value); | |
166750bc AN |
1813 | return -EINVAL; |
1814 | } | |
1815 | ||
1816 | len = strlen(value); | |
1817 | if (value[len - 1] != '"') { | |
2e33efe3 | 1818 | pr_warn("extern (kcfg) '%s': invalid string config '%s'\n", |
166750bc AN |
1819 | ext->name, value); |
1820 | return -EINVAL; | |
1821 | } | |
1822 | ||
1823 | /* strip quotes */ | |
1824 | len -= 2; | |
2e33efe3 | 1825 | if (len >= ext->kcfg.sz) { |
55d00c37 | 1826 | pr_warn("extern (kcfg) '%s': long string '%s' of (%zu bytes) truncated to %d bytes\n", |
2e33efe3 AN |
1827 | ext->name, value, len, ext->kcfg.sz - 1); |
1828 | len = ext->kcfg.sz - 1; | |
166750bc AN |
1829 | } |
1830 | memcpy(ext_val, value + 1, len); | |
1831 | ext_val[len] = '\0'; | |
1832 | ext->is_set = true; | |
1833 | return 0; | |
1834 | } | |
1835 | ||
1836 | static int parse_u64(const char *value, __u64 *res) | |
1837 | { | |
1838 | char *value_end; | |
1839 | int err; | |
1840 | ||
1841 | errno = 0; | |
1842 | *res = strtoull(value, &value_end, 0); | |
1843 | if (errno) { | |
1844 | err = -errno; | |
1845 | pr_warn("failed to parse '%s' as integer: %d\n", value, err); | |
1846 | return err; | |
1847 | } | |
1848 | if (*value_end) { | |
1849 | pr_warn("failed to parse '%s' as integer completely\n", value); | |
1850 | return -EINVAL; | |
1851 | } | |
1852 | return 0; | |
1853 | } | |
1854 | ||
2e33efe3 | 1855 | static bool is_kcfg_value_in_range(const struct extern_desc *ext, __u64 v) |
166750bc | 1856 | { |
2e33efe3 | 1857 | int bit_sz = ext->kcfg.sz * 8; |
166750bc | 1858 | |
2e33efe3 | 1859 | if (ext->kcfg.sz == 8) |
166750bc AN |
1860 | return true; |
1861 | ||
1862 | /* Validate that value stored in u64 fits in integer of `ext->sz` | |
1863 | * bytes size without any loss of information. If the target integer | |
1864 | * is signed, we rely on the following limits of integer type of | |
1865 | * Y bits and subsequent transformation: | |
1866 | * | |
1867 | * -2^(Y-1) <= X <= 2^(Y-1) - 1 | |
1868 | * 0 <= X + 2^(Y-1) <= 2^Y - 1 | |
1869 | * 0 <= X + 2^(Y-1) < 2^Y | |
1870 | * | |
1871 | * For unsigned target integer, check that all the (64 - Y) bits are | |
1872 | * zero. | |
1873 | */ | |
2e33efe3 | 1874 | if (ext->kcfg.is_signed) |
166750bc AN |
1875 | return v + (1ULL << (bit_sz - 1)) < (1ULL << bit_sz); |
1876 | else | |
1877 | return (v >> bit_sz) == 0; | |
1878 | } | |
1879 | ||
2e33efe3 AN |
1880 | static int set_kcfg_value_num(struct extern_desc *ext, void *ext_val, |
1881 | __u64 value) | |
166750bc | 1882 | { |
55d00c37 AN |
1883 | if (ext->kcfg.type != KCFG_INT && ext->kcfg.type != KCFG_CHAR && |
1884 | ext->kcfg.type != KCFG_BOOL) { | |
1885 | pr_warn("extern (kcfg) '%s': value '%llu' implies integer, char, or boolean type\n", | |
7745ff98 | 1886 | ext->name, (unsigned long long)value); |
166750bc AN |
1887 | return -EINVAL; |
1888 | } | |
55d00c37 AN |
1889 | if (ext->kcfg.type == KCFG_BOOL && value > 1) { |
1890 | pr_warn("extern (kcfg) '%s': value '%llu' isn't boolean compatible\n", | |
1891 | ext->name, (unsigned long long)value); | |
1892 | return -EINVAL; | |
1893 | ||
1894 | } | |
2e33efe3 | 1895 | if (!is_kcfg_value_in_range(ext, value)) { |
55d00c37 | 1896 | pr_warn("extern (kcfg) '%s': value '%llu' doesn't fit in %d bytes\n", |
2e33efe3 | 1897 | ext->name, (unsigned long long)value, ext->kcfg.sz); |
166750bc AN |
1898 | return -ERANGE; |
1899 | } | |
2e33efe3 | 1900 | switch (ext->kcfg.sz) { |
e3ba8e4e KM |
1901 | case 1: |
1902 | *(__u8 *)ext_val = value; | |
1903 | break; | |
1904 | case 2: | |
1905 | *(__u16 *)ext_val = value; | |
1906 | break; | |
1907 | case 4: | |
1908 | *(__u32 *)ext_val = value; | |
1909 | break; | |
1910 | case 8: | |
1911 | *(__u64 *)ext_val = value; | |
1912 | break; | |
1913 | default: | |
1914 | return -EINVAL; | |
166750bc AN |
1915 | } |
1916 | ext->is_set = true; | |
1917 | return 0; | |
1918 | } | |
1919 | ||
8601fd42 AN |
1920 | static int bpf_object__process_kconfig_line(struct bpf_object *obj, |
1921 | char *buf, void *data) | |
166750bc | 1922 | { |
166750bc | 1923 | struct extern_desc *ext; |
8601fd42 | 1924 | char *sep, *value; |
166750bc AN |
1925 | int len, err = 0; |
1926 | void *ext_val; | |
1927 | __u64 num; | |
166750bc | 1928 | |
13d35a0c | 1929 | if (!str_has_pfx(buf, "CONFIG_")) |
8601fd42 | 1930 | return 0; |
166750bc | 1931 | |
8601fd42 AN |
1932 | sep = strchr(buf, '='); |
1933 | if (!sep) { | |
1934 | pr_warn("failed to parse '%s': no separator\n", buf); | |
1935 | return -EINVAL; | |
1936 | } | |
1937 | ||
1938 | /* Trim ending '\n' */ | |
1939 | len = strlen(buf); | |
1940 | if (buf[len - 1] == '\n') | |
1941 | buf[len - 1] = '\0'; | |
1942 | /* Split on '=' and ensure that a value is present. */ | |
1943 | *sep = '\0'; | |
1944 | if (!sep[1]) { | |
1945 | *sep = '='; | |
1946 | pr_warn("failed to parse '%s': no value\n", buf); | |
1947 | return -EINVAL; | |
1948 | } | |
1949 | ||
1950 | ext = find_extern_by_name(obj, buf); | |
1951 | if (!ext || ext->is_set) | |
1952 | return 0; | |
1953 | ||
2e33efe3 | 1954 | ext_val = data + ext->kcfg.data_off; |
8601fd42 AN |
1955 | value = sep + 1; |
1956 | ||
1957 | switch (*value) { | |
1958 | case 'y': case 'n': case 'm': | |
2e33efe3 | 1959 | err = set_kcfg_value_tri(ext, ext_val, *value); |
8601fd42 AN |
1960 | break; |
1961 | case '"': | |
2e33efe3 | 1962 | err = set_kcfg_value_str(ext, ext_val, value); |
8601fd42 AN |
1963 | break; |
1964 | default: | |
1965 | /* assume integer */ | |
1966 | err = parse_u64(value, &num); | |
1967 | if (err) { | |
55d00c37 | 1968 | pr_warn("extern (kcfg) '%s': value '%s' isn't a valid integer\n", ext->name, value); |
8601fd42 AN |
1969 | return err; |
1970 | } | |
55d00c37 AN |
1971 | if (ext->kcfg.type != KCFG_INT && ext->kcfg.type != KCFG_CHAR) { |
1972 | pr_warn("extern (kcfg) '%s': value '%s' implies integer type\n", ext->name, value); | |
1973 | return -EINVAL; | |
1974 | } | |
2e33efe3 | 1975 | err = set_kcfg_value_num(ext, ext_val, num); |
8601fd42 | 1976 | break; |
166750bc | 1977 | } |
8601fd42 AN |
1978 | if (err) |
1979 | return err; | |
55d00c37 | 1980 | pr_debug("extern (kcfg) '%s': set to %s\n", ext->name, value); |
8601fd42 AN |
1981 | return 0; |
1982 | } | |
1983 | ||
1984 | static int bpf_object__read_kconfig_file(struct bpf_object *obj, void *data) | |
1985 | { | |
1986 | char buf[PATH_MAX]; | |
1987 | struct utsname uts; | |
1988 | int len, err = 0; | |
1989 | gzFile file; | |
1990 | ||
1991 | uname(&uts); | |
1992 | len = snprintf(buf, PATH_MAX, "/boot/config-%s", uts.release); | |
1993 | if (len < 0) | |
1994 | return -EINVAL; | |
1995 | else if (len >= PATH_MAX) | |
1996 | return -ENAMETOOLONG; | |
1997 | ||
1998 | /* gzopen also accepts uncompressed files. */ | |
8e50750f | 1999 | file = gzopen(buf, "re"); |
8601fd42 | 2000 | if (!file) |
8e50750f | 2001 | file = gzopen("/proc/config.gz", "re"); |
8601fd42 | 2002 | |
166750bc | 2003 | if (!file) { |
8601fd42 | 2004 | pr_warn("failed to open system Kconfig\n"); |
166750bc AN |
2005 | return -ENOENT; |
2006 | } | |
2007 | ||
2008 | while (gzgets(file, buf, sizeof(buf))) { | |
8601fd42 AN |
2009 | err = bpf_object__process_kconfig_line(obj, buf, data); |
2010 | if (err) { | |
2011 | pr_warn("error parsing system Kconfig line '%s': %d\n", | |
2012 | buf, err); | |
166750bc AN |
2013 | goto out; |
2014 | } | |
8601fd42 | 2015 | } |
166750bc | 2016 | |
8601fd42 AN |
2017 | out: |
2018 | gzclose(file); | |
2019 | return err; | |
2020 | } | |
166750bc | 2021 | |
8601fd42 AN |
2022 | static int bpf_object__read_kconfig_mem(struct bpf_object *obj, |
2023 | const char *config, void *data) | |
2024 | { | |
2025 | char buf[PATH_MAX]; | |
2026 | int err = 0; | |
2027 | FILE *file; | |
166750bc | 2028 | |
8601fd42 AN |
2029 | file = fmemopen((void *)config, strlen(config), "r"); |
2030 | if (!file) { | |
2031 | err = -errno; | |
2032 | pr_warn("failed to open in-memory Kconfig: %d\n", err); | |
2033 | return err; | |
2034 | } | |
2035 | ||
2036 | while (fgets(buf, sizeof(buf), file)) { | |
2037 | err = bpf_object__process_kconfig_line(obj, buf, data); | |
2038 | if (err) { | |
2039 | pr_warn("error parsing in-memory Kconfig line '%s': %d\n", | |
2040 | buf, err); | |
166750bc AN |
2041 | break; |
2042 | } | |
166750bc AN |
2043 | } |
2044 | ||
8601fd42 | 2045 | fclose(file); |
166750bc AN |
2046 | return err; |
2047 | } | |
2048 | ||
81bfdd08 | 2049 | static int bpf_object__init_kconfig_map(struct bpf_object *obj) |
166750bc | 2050 | { |
2e33efe3 | 2051 | struct extern_desc *last_ext = NULL, *ext; |
166750bc | 2052 | size_t map_sz; |
2e33efe3 | 2053 | int i, err; |
166750bc | 2054 | |
2e33efe3 AN |
2055 | for (i = 0; i < obj->nr_extern; i++) { |
2056 | ext = &obj->externs[i]; | |
2057 | if (ext->type == EXT_KCFG) | |
2058 | last_ext = ext; | |
2059 | } | |
166750bc | 2060 | |
2e33efe3 AN |
2061 | if (!last_ext) |
2062 | return 0; | |
166750bc | 2063 | |
2e33efe3 | 2064 | map_sz = last_ext->kcfg.data_off + last_ext->kcfg.sz; |
81bfdd08 | 2065 | err = bpf_object__init_internal_map(obj, LIBBPF_MAP_KCONFIG, |
aed65917 | 2066 | ".kconfig", obj->efile.symbols_shndx, |
166750bc AN |
2067 | NULL, map_sz); |
2068 | if (err) | |
2069 | return err; | |
2070 | ||
81bfdd08 | 2071 | obj->kconfig_map_idx = obj->nr_maps - 1; |
166750bc AN |
2072 | |
2073 | return 0; | |
2074 | } | |
2075 | ||
42869d28 | 2076 | const struct btf_type * |
ddc7c304 | 2077 | skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id) |
abd29c93 AN |
2078 | { |
2079 | const struct btf_type *t = btf__type_by_id(btf, id); | |
8837fe5d | 2080 | |
ddc7c304 AN |
2081 | if (res_id) |
2082 | *res_id = id; | |
2083 | ||
2084 | while (btf_is_mod(t) || btf_is_typedef(t)) { | |
2085 | if (res_id) | |
2086 | *res_id = t->type; | |
2087 | t = btf__type_by_id(btf, t->type); | |
abd29c93 | 2088 | } |
ddc7c304 AN |
2089 | |
2090 | return t; | |
abd29c93 AN |
2091 | } |
2092 | ||
590a0088 MKL |
2093 | static const struct btf_type * |
2094 | resolve_func_ptr(const struct btf *btf, __u32 id, __u32 *res_id) | |
2095 | { | |
2096 | const struct btf_type *t; | |
2097 | ||
2098 | t = skip_mods_and_typedefs(btf, id, NULL); | |
2099 | if (!btf_is_ptr(t)) | |
2100 | return NULL; | |
2101 | ||
2102 | t = skip_mods_and_typedefs(btf, t->type, res_id); | |
2103 | ||
2104 | return btf_is_func_proto(t) ? t : NULL; | |
2105 | } | |
2106 | ||
774e132e | 2107 | static const char *__btf_kind_str(__u16 kind) |
81ba0889 | 2108 | { |
774e132e | 2109 | switch (kind) { |
81ba0889 AN |
2110 | case BTF_KIND_UNKN: return "void"; |
2111 | case BTF_KIND_INT: return "int"; | |
2112 | case BTF_KIND_PTR: return "ptr"; | |
2113 | case BTF_KIND_ARRAY: return "array"; | |
2114 | case BTF_KIND_STRUCT: return "struct"; | |
2115 | case BTF_KIND_UNION: return "union"; | |
2116 | case BTF_KIND_ENUM: return "enum"; | |
2117 | case BTF_KIND_FWD: return "fwd"; | |
2118 | case BTF_KIND_TYPEDEF: return "typedef"; | |
2119 | case BTF_KIND_VOLATILE: return "volatile"; | |
2120 | case BTF_KIND_CONST: return "const"; | |
2121 | case BTF_KIND_RESTRICT: return "restrict"; | |
2122 | case BTF_KIND_FUNC: return "func"; | |
2123 | case BTF_KIND_FUNC_PROTO: return "func_proto"; | |
2124 | case BTF_KIND_VAR: return "var"; | |
2125 | case BTF_KIND_DATASEC: return "datasec"; | |
22541a9e | 2126 | case BTF_KIND_FLOAT: return "float"; |
223f903e | 2127 | case BTF_KIND_DECL_TAG: return "decl_tag"; |
2dc1e488 | 2128 | case BTF_KIND_TYPE_TAG: return "type_tag"; |
f2a62588 | 2129 | case BTF_KIND_ENUM64: return "enum64"; |
81ba0889 AN |
2130 | default: return "unknown"; |
2131 | } | |
2132 | } | |
2133 | ||
42869d28 | 2134 | const char *btf_kind_str(const struct btf_type *t) |
774e132e MKL |
2135 | { |
2136 | return __btf_kind_str(btf_kind(t)); | |
2137 | } | |
2138 | ||
ef99b02b AN |
2139 | /* |
2140 | * Fetch integer attribute of BTF map definition. Such attributes are | |
2141 | * represented using a pointer to an array, in which dimensionality of array | |
2142 | * encodes specified integer value. E.g., int (*type)[BPF_MAP_TYPE_ARRAY]; | |
2143 | * encodes `type => BPF_MAP_TYPE_ARRAY` key/value pair completely using BTF | |
2144 | * type definition, while using only sizeof(void *) space in ELF data section. | |
2145 | */ | |
2146 | static bool get_map_field_int(const char *map_name, const struct btf *btf, | |
8983b731 AN |
2147 | const struct btf_member *m, __u32 *res) |
2148 | { | |
ddc7c304 | 2149 | const struct btf_type *t = skip_mods_and_typedefs(btf, m->type, NULL); |
abd29c93 | 2150 | const char *name = btf__name_by_offset(btf, m->name_off); |
ef99b02b AN |
2151 | const struct btf_array *arr_info; |
2152 | const struct btf_type *arr_t; | |
abd29c93 | 2153 | |
b03bc685 | 2154 | if (!btf_is_ptr(t)) { |
81ba0889 AN |
2155 | pr_warn("map '%s': attr '%s': expected PTR, got %s.\n", |
2156 | map_name, name, btf_kind_str(t)); | |
abd29c93 AN |
2157 | return false; |
2158 | } | |
ef99b02b AN |
2159 | |
2160 | arr_t = btf__type_by_id(btf, t->type); | |
2161 | if (!arr_t) { | |
be18010e KW |
2162 | pr_warn("map '%s': attr '%s': type [%u] not found.\n", |
2163 | map_name, name, t->type); | |
abd29c93 AN |
2164 | return false; |
2165 | } | |
b03bc685 | 2166 | if (!btf_is_array(arr_t)) { |
81ba0889 AN |
2167 | pr_warn("map '%s': attr '%s': expected ARRAY, got %s.\n", |
2168 | map_name, name, btf_kind_str(arr_t)); | |
abd29c93 AN |
2169 | return false; |
2170 | } | |
b03bc685 | 2171 | arr_info = btf_array(arr_t); |
ef99b02b | 2172 | *res = arr_info->nelems; |
abd29c93 AN |
2173 | return true; |
2174 | } | |
2175 | ||
e588c116 WY |
2176 | static int pathname_concat(char *buf, size_t buf_sz, const char *path, const char *name) |
2177 | { | |
2178 | int len; | |
2179 | ||
2180 | len = snprintf(buf, buf_sz, "%s/%s", path, name); | |
2181 | if (len < 0) | |
2182 | return -EINVAL; | |
2183 | if (len >= buf_sz) | |
2184 | return -ENAMETOOLONG; | |
2185 | ||
2186 | return 0; | |
2187 | } | |
2188 | ||
57a00f41 THJ |
2189 | static int build_map_pin_path(struct bpf_map *map, const char *path) |
2190 | { | |
2191 | char buf[PATH_MAX]; | |
e588c116 | 2192 | int err; |
57a00f41 THJ |
2193 | |
2194 | if (!path) | |
2195 | path = "/sys/fs/bpf"; | |
2196 | ||
e588c116 WY |
2197 | err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map)); |
2198 | if (err) | |
2199 | return err; | |
57a00f41 | 2200 | |
6e9cab2e | 2201 | return bpf_map__set_pin_path(map, buf); |
57a00f41 THJ |
2202 | } |
2203 | ||
146bf811 AN |
2204 | /* should match definition in bpf_helpers.h */ |
2205 | enum libbpf_pin_type { | |
2206 | LIBBPF_PIN_NONE, | |
2207 | /* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */ | |
2208 | LIBBPF_PIN_BY_NAME, | |
2209 | }; | |
2210 | ||
c7ef5ec9 AN |
2211 | int parse_btf_map_def(const char *map_name, struct btf *btf, |
2212 | const struct btf_type *def_t, bool strict, | |
2213 | struct btf_map_def *map_def, struct btf_map_def *inner_def) | |
abd29c93 | 2214 | { |
41017e56 | 2215 | const struct btf_type *t; |
abd29c93 | 2216 | const struct btf_member *m; |
c7ef5ec9 | 2217 | bool is_inner = inner_def == NULL; |
abd29c93 AN |
2218 | int vlen, i; |
2219 | ||
c7ef5ec9 AN |
2220 | vlen = btf_vlen(def_t); |
2221 | m = btf_members(def_t); | |
abd29c93 | 2222 | for (i = 0; i < vlen; i++, m++) { |
c7ef5ec9 | 2223 | const char *name = btf__name_by_offset(btf, m->name_off); |
abd29c93 AN |
2224 | |
2225 | if (!name) { | |
c7ef5ec9 | 2226 | pr_warn("map '%s': invalid field #%d.\n", map_name, i); |
abd29c93 AN |
2227 | return -EINVAL; |
2228 | } | |
2229 | if (strcmp(name, "type") == 0) { | |
c7ef5ec9 | 2230 | if (!get_map_field_int(map_name, btf, m, &map_def->map_type)) |
abd29c93 | 2231 | return -EINVAL; |
c7ef5ec9 | 2232 | map_def->parts |= MAP_DEF_MAP_TYPE; |
abd29c93 | 2233 | } else if (strcmp(name, "max_entries") == 0) { |
c7ef5ec9 | 2234 | if (!get_map_field_int(map_name, btf, m, &map_def->max_entries)) |
abd29c93 | 2235 | return -EINVAL; |
c7ef5ec9 | 2236 | map_def->parts |= MAP_DEF_MAX_ENTRIES; |
abd29c93 | 2237 | } else if (strcmp(name, "map_flags") == 0) { |
c7ef5ec9 | 2238 | if (!get_map_field_int(map_name, btf, m, &map_def->map_flags)) |
abd29c93 | 2239 | return -EINVAL; |
c7ef5ec9 | 2240 | map_def->parts |= MAP_DEF_MAP_FLAGS; |
1bdb6c9a | 2241 | } else if (strcmp(name, "numa_node") == 0) { |
c7ef5ec9 | 2242 | if (!get_map_field_int(map_name, btf, m, &map_def->numa_node)) |
1bdb6c9a | 2243 | return -EINVAL; |
c7ef5ec9 | 2244 | map_def->parts |= MAP_DEF_NUMA_NODE; |
abd29c93 AN |
2245 | } else if (strcmp(name, "key_size") == 0) { |
2246 | __u32 sz; | |
2247 | ||
c7ef5ec9 | 2248 | if (!get_map_field_int(map_name, btf, m, &sz)) |
abd29c93 | 2249 | return -EINVAL; |
c7ef5ec9 | 2250 | if (map_def->key_size && map_def->key_size != sz) { |
be18010e | 2251 | pr_warn("map '%s': conflicting key size %u != %u.\n", |
c7ef5ec9 | 2252 | map_name, map_def->key_size, sz); |
abd29c93 AN |
2253 | return -EINVAL; |
2254 | } | |
c7ef5ec9 AN |
2255 | map_def->key_size = sz; |
2256 | map_def->parts |= MAP_DEF_KEY_SIZE; | |
abd29c93 AN |
2257 | } else if (strcmp(name, "key") == 0) { |
2258 | __s64 sz; | |
2259 | ||
c7ef5ec9 | 2260 | t = btf__type_by_id(btf, m->type); |
abd29c93 | 2261 | if (!t) { |
be18010e | 2262 | pr_warn("map '%s': key type [%d] not found.\n", |
c7ef5ec9 | 2263 | map_name, m->type); |
abd29c93 AN |
2264 | return -EINVAL; |
2265 | } | |
b03bc685 | 2266 | if (!btf_is_ptr(t)) { |
81ba0889 | 2267 | pr_warn("map '%s': key spec is not PTR: %s.\n", |
c7ef5ec9 | 2268 | map_name, btf_kind_str(t)); |
abd29c93 AN |
2269 | return -EINVAL; |
2270 | } | |
c7ef5ec9 | 2271 | sz = btf__resolve_size(btf, t->type); |
abd29c93 | 2272 | if (sz < 0) { |
679152d3 | 2273 | pr_warn("map '%s': can't determine key size for type [%u]: %zd.\n", |
c7ef5ec9 | 2274 | map_name, t->type, (ssize_t)sz); |
abd29c93 AN |
2275 | return sz; |
2276 | } | |
c7ef5ec9 | 2277 | if (map_def->key_size && map_def->key_size != sz) { |
679152d3 | 2278 | pr_warn("map '%s': conflicting key size %u != %zd.\n", |
c7ef5ec9 | 2279 | map_name, map_def->key_size, (ssize_t)sz); |
abd29c93 AN |
2280 | return -EINVAL; |
2281 | } | |
c7ef5ec9 AN |
2282 | map_def->key_size = sz; |
2283 | map_def->key_type_id = t->type; | |
2284 | map_def->parts |= MAP_DEF_KEY_SIZE | MAP_DEF_KEY_TYPE; | |
abd29c93 AN |
2285 | } else if (strcmp(name, "value_size") == 0) { |
2286 | __u32 sz; | |
2287 | ||
c7ef5ec9 | 2288 | if (!get_map_field_int(map_name, btf, m, &sz)) |
abd29c93 | 2289 | return -EINVAL; |
c7ef5ec9 | 2290 | if (map_def->value_size && map_def->value_size != sz) { |
be18010e | 2291 | pr_warn("map '%s': conflicting value size %u != %u.\n", |
c7ef5ec9 | 2292 | map_name, map_def->value_size, sz); |
abd29c93 AN |
2293 | return -EINVAL; |
2294 | } | |
c7ef5ec9 AN |
2295 | map_def->value_size = sz; |
2296 | map_def->parts |= MAP_DEF_VALUE_SIZE; | |
abd29c93 AN |
2297 | } else if (strcmp(name, "value") == 0) { |
2298 | __s64 sz; | |
2299 | ||
c7ef5ec9 | 2300 | t = btf__type_by_id(btf, m->type); |
abd29c93 | 2301 | if (!t) { |
be18010e | 2302 | pr_warn("map '%s': value type [%d] not found.\n", |
c7ef5ec9 | 2303 | map_name, m->type); |
abd29c93 AN |
2304 | return -EINVAL; |
2305 | } | |
b03bc685 | 2306 | if (!btf_is_ptr(t)) { |
81ba0889 | 2307 | pr_warn("map '%s': value spec is not PTR: %s.\n", |
c7ef5ec9 | 2308 | map_name, btf_kind_str(t)); |
abd29c93 AN |
2309 | return -EINVAL; |
2310 | } | |
c7ef5ec9 | 2311 | sz = btf__resolve_size(btf, t->type); |
abd29c93 | 2312 | if (sz < 0) { |
679152d3 | 2313 | pr_warn("map '%s': can't determine value size for type [%u]: %zd.\n", |
c7ef5ec9 | 2314 | map_name, t->type, (ssize_t)sz); |
abd29c93 AN |
2315 | return sz; |
2316 | } | |
c7ef5ec9 | 2317 | if (map_def->value_size && map_def->value_size != sz) { |
679152d3 | 2318 | pr_warn("map '%s': conflicting value size %u != %zd.\n", |
c7ef5ec9 | 2319 | map_name, map_def->value_size, (ssize_t)sz); |
abd29c93 AN |
2320 | return -EINVAL; |
2321 | } | |
c7ef5ec9 AN |
2322 | map_def->value_size = sz; |
2323 | map_def->value_type_id = t->type; | |
2324 | map_def->parts |= MAP_DEF_VALUE_SIZE | MAP_DEF_VALUE_TYPE; | |
646f02ff AN |
2325 | } |
2326 | else if (strcmp(name, "values") == 0) { | |
341ac5ff HC |
2327 | bool is_map_in_map = bpf_map_type__is_map_in_map(map_def->map_type); |
2328 | bool is_prog_array = map_def->map_type == BPF_MAP_TYPE_PROG_ARRAY; | |
2329 | const char *desc = is_map_in_map ? "map-in-map inner" : "prog-array value"; | |
c7ef5ec9 | 2330 | char inner_map_name[128]; |
646f02ff AN |
2331 | int err; |
2332 | ||
2333 | if (is_inner) { | |
2334 | pr_warn("map '%s': multi-level inner maps not supported.\n", | |
c7ef5ec9 | 2335 | map_name); |
646f02ff AN |
2336 | return -ENOTSUP; |
2337 | } | |
2338 | if (i != vlen - 1) { | |
2339 | pr_warn("map '%s': '%s' member should be last.\n", | |
c7ef5ec9 | 2340 | map_name, name); |
646f02ff AN |
2341 | return -EINVAL; |
2342 | } | |
341ac5ff HC |
2343 | if (!is_map_in_map && !is_prog_array) { |
2344 | pr_warn("map '%s': should be map-in-map or prog-array.\n", | |
c7ef5ec9 | 2345 | map_name); |
646f02ff AN |
2346 | return -ENOTSUP; |
2347 | } | |
c7ef5ec9 | 2348 | if (map_def->value_size && map_def->value_size != 4) { |
646f02ff | 2349 | pr_warn("map '%s': conflicting value size %u != 4.\n", |
c7ef5ec9 | 2350 | map_name, map_def->value_size); |
646f02ff AN |
2351 | return -EINVAL; |
2352 | } | |
c7ef5ec9 AN |
2353 | map_def->value_size = 4; |
2354 | t = btf__type_by_id(btf, m->type); | |
646f02ff | 2355 | if (!t) { |
341ac5ff HC |
2356 | pr_warn("map '%s': %s type [%d] not found.\n", |
2357 | map_name, desc, m->type); | |
646f02ff AN |
2358 | return -EINVAL; |
2359 | } | |
2360 | if (!btf_is_array(t) || btf_array(t)->nelems) { | |
341ac5ff HC |
2361 | pr_warn("map '%s': %s spec is not a zero-sized array.\n", |
2362 | map_name, desc); | |
646f02ff AN |
2363 | return -EINVAL; |
2364 | } | |
c7ef5ec9 | 2365 | t = skip_mods_and_typedefs(btf, btf_array(t)->type, NULL); |
646f02ff | 2366 | if (!btf_is_ptr(t)) { |
341ac5ff HC |
2367 | pr_warn("map '%s': %s def is of unexpected kind %s.\n", |
2368 | map_name, desc, btf_kind_str(t)); | |
646f02ff AN |
2369 | return -EINVAL; |
2370 | } | |
c7ef5ec9 | 2371 | t = skip_mods_and_typedefs(btf, t->type, NULL); |
341ac5ff HC |
2372 | if (is_prog_array) { |
2373 | if (!btf_is_func_proto(t)) { | |
2374 | pr_warn("map '%s': prog-array value def is of unexpected kind %s.\n", | |
2375 | map_name, btf_kind_str(t)); | |
2376 | return -EINVAL; | |
2377 | } | |
2378 | continue; | |
2379 | } | |
646f02ff | 2380 | if (!btf_is_struct(t)) { |
81ba0889 | 2381 | pr_warn("map '%s': map-in-map inner def is of unexpected kind %s.\n", |
c7ef5ec9 | 2382 | map_name, btf_kind_str(t)); |
646f02ff AN |
2383 | return -EINVAL; |
2384 | } | |
2385 | ||
c7ef5ec9 AN |
2386 | snprintf(inner_map_name, sizeof(inner_map_name), "%s.inner", map_name); |
2387 | err = parse_btf_map_def(inner_map_name, btf, t, strict, inner_def, NULL); | |
646f02ff AN |
2388 | if (err) |
2389 | return err; | |
c7ef5ec9 AN |
2390 | |
2391 | map_def->parts |= MAP_DEF_INNER_MAP; | |
57a00f41 THJ |
2392 | } else if (strcmp(name, "pinning") == 0) { |
2393 | __u32 val; | |
57a00f41 | 2394 | |
646f02ff | 2395 | if (is_inner) { |
c7ef5ec9 | 2396 | pr_warn("map '%s': inner def can't be pinned.\n", map_name); |
646f02ff AN |
2397 | return -EINVAL; |
2398 | } | |
c7ef5ec9 | 2399 | if (!get_map_field_int(map_name, btf, m, &val)) |
57a00f41 | 2400 | return -EINVAL; |
c7ef5ec9 | 2401 | if (val != LIBBPF_PIN_NONE && val != LIBBPF_PIN_BY_NAME) { |
57a00f41 | 2402 | pr_warn("map '%s': invalid pinning value %u.\n", |
c7ef5ec9 | 2403 | map_name, val); |
57a00f41 THJ |
2404 | return -EINVAL; |
2405 | } | |
c7ef5ec9 AN |
2406 | map_def->pinning = val; |
2407 | map_def->parts |= MAP_DEF_PINNING; | |
47512102 JK |
2408 | } else if (strcmp(name, "map_extra") == 0) { |
2409 | __u32 map_extra; | |
2410 | ||
2411 | if (!get_map_field_int(map_name, btf, m, &map_extra)) | |
2412 | return -EINVAL; | |
2413 | map_def->map_extra = map_extra; | |
2414 | map_def->parts |= MAP_DEF_MAP_EXTRA; | |
abd29c93 AN |
2415 | } else { |
2416 | if (strict) { | |
c7ef5ec9 | 2417 | pr_warn("map '%s': unknown field '%s'.\n", map_name, name); |
abd29c93 AN |
2418 | return -ENOTSUP; |
2419 | } | |
c7ef5ec9 | 2420 | pr_debug("map '%s': ignoring unknown field '%s'.\n", map_name, name); |
abd29c93 AN |
2421 | } |
2422 | } | |
2423 | ||
c7ef5ec9 AN |
2424 | if (map_def->map_type == BPF_MAP_TYPE_UNSPEC) { |
2425 | pr_warn("map '%s': map type isn't specified.\n", map_name); | |
abd29c93 AN |
2426 | return -EINVAL; |
2427 | } | |
2428 | ||
2429 | return 0; | |
2430 | } | |
2431 | ||
597fbc46 AN |
2432 | static size_t adjust_ringbuf_sz(size_t sz) |
2433 | { | |
2434 | __u32 page_sz = sysconf(_SC_PAGE_SIZE); | |
2435 | __u32 mul; | |
2436 | ||
2437 | /* if user forgot to set any size, make sure they see error */ | |
2438 | if (sz == 0) | |
2439 | return 0; | |
2440 | /* Kernel expects BPF_MAP_TYPE_RINGBUF's max_entries to be | |
2441 | * a power-of-2 multiple of kernel's page size. If user diligently | |
2442 | * satisified these conditions, pass the size through. | |
2443 | */ | |
2444 | if ((sz % page_sz) == 0 && is_pow_of_2(sz / page_sz)) | |
2445 | return sz; | |
2446 | ||
2447 | /* Otherwise find closest (page_sz * power_of_2) product bigger than | |
2448 | * user-set size to satisfy both user size request and kernel | |
2449 | * requirements and substitute correct max_entries for map creation. | |
2450 | */ | |
2451 | for (mul = 1; mul <= UINT_MAX / page_sz; mul <<= 1) { | |
2452 | if (mul * page_sz > sz) | |
2453 | return mul * page_sz; | |
2454 | } | |
2455 | ||
2456 | /* if it's impossible to satisfy the conditions (i.e., user size is | |
2457 | * very close to UINT_MAX but is not a power-of-2 multiple of | |
2458 | * page_size) then just return original size and let kernel reject it | |
2459 | */ | |
2460 | return sz; | |
2461 | } | |
2462 | ||
b66ccae0 DV |
2463 | static bool map_is_ringbuf(const struct bpf_map *map) |
2464 | { | |
2465 | return map->def.type == BPF_MAP_TYPE_RINGBUF || | |
2466 | map->def.type == BPF_MAP_TYPE_USER_RINGBUF; | |
2467 | } | |
2468 | ||
c7ef5ec9 AN |
2469 | static void fill_map_from_def(struct bpf_map *map, const struct btf_map_def *def) |
2470 | { | |
2471 | map->def.type = def->map_type; | |
2472 | map->def.key_size = def->key_size; | |
2473 | map->def.value_size = def->value_size; | |
2474 | map->def.max_entries = def->max_entries; | |
2475 | map->def.map_flags = def->map_flags; | |
47512102 | 2476 | map->map_extra = def->map_extra; |
c7ef5ec9 AN |
2477 | |
2478 | map->numa_node = def->numa_node; | |
2479 | map->btf_key_type_id = def->key_type_id; | |
2480 | map->btf_value_type_id = def->value_type_id; | |
2481 | ||
597fbc46 | 2482 | /* auto-adjust BPF ringbuf map max_entries to be a multiple of page size */ |
b66ccae0 | 2483 | if (map_is_ringbuf(map)) |
597fbc46 AN |
2484 | map->def.max_entries = adjust_ringbuf_sz(map->def.max_entries); |
2485 | ||
c7ef5ec9 AN |
2486 | if (def->parts & MAP_DEF_MAP_TYPE) |
2487 | pr_debug("map '%s': found type = %u.\n", map->name, def->map_type); | |
2488 | ||
2489 | if (def->parts & MAP_DEF_KEY_TYPE) | |
2490 | pr_debug("map '%s': found key [%u], sz = %u.\n", | |
2491 | map->name, def->key_type_id, def->key_size); | |
2492 | else if (def->parts & MAP_DEF_KEY_SIZE) | |
2493 | pr_debug("map '%s': found key_size = %u.\n", map->name, def->key_size); | |
2494 | ||
2495 | if (def->parts & MAP_DEF_VALUE_TYPE) | |
2496 | pr_debug("map '%s': found value [%u], sz = %u.\n", | |
2497 | map->name, def->value_type_id, def->value_size); | |
2498 | else if (def->parts & MAP_DEF_VALUE_SIZE) | |
2499 | pr_debug("map '%s': found value_size = %u.\n", map->name, def->value_size); | |
2500 | ||
2501 | if (def->parts & MAP_DEF_MAX_ENTRIES) | |
2502 | pr_debug("map '%s': found max_entries = %u.\n", map->name, def->max_entries); | |
2503 | if (def->parts & MAP_DEF_MAP_FLAGS) | |
47512102 JK |
2504 | pr_debug("map '%s': found map_flags = 0x%x.\n", map->name, def->map_flags); |
2505 | if (def->parts & MAP_DEF_MAP_EXTRA) | |
2506 | pr_debug("map '%s': found map_extra = 0x%llx.\n", map->name, | |
2507 | (unsigned long long)def->map_extra); | |
c7ef5ec9 AN |
2508 | if (def->parts & MAP_DEF_PINNING) |
2509 | pr_debug("map '%s': found pinning = %u.\n", map->name, def->pinning); | |
2510 | if (def->parts & MAP_DEF_NUMA_NODE) | |
2511 | pr_debug("map '%s': found numa_node = %u.\n", map->name, def->numa_node); | |
2512 | ||
2513 | if (def->parts & MAP_DEF_INNER_MAP) | |
2514 | pr_debug("map '%s': found inner map definition.\n", map->name); | |
2515 | } | |
2516 | ||
c1cccec9 AN |
2517 | static const char *btf_var_linkage_str(__u32 linkage) |
2518 | { | |
2519 | switch (linkage) { | |
2520 | case BTF_VAR_STATIC: return "static"; | |
2521 | case BTF_VAR_GLOBAL_ALLOCATED: return "global"; | |
2522 | case BTF_VAR_GLOBAL_EXTERN: return "extern"; | |
2523 | default: return "unknown"; | |
2524 | } | |
2525 | } | |
2526 | ||
41017e56 AN |
2527 | static int bpf_object__init_user_btf_map(struct bpf_object *obj, |
2528 | const struct btf_type *sec, | |
2529 | int var_idx, int sec_idx, | |
2530 | const Elf_Data *data, bool strict, | |
2531 | const char *pin_root_path) | |
2532 | { | |
c7ef5ec9 | 2533 | struct btf_map_def map_def = {}, inner_def = {}; |
41017e56 AN |
2534 | const struct btf_type *var, *def; |
2535 | const struct btf_var_secinfo *vi; | |
2536 | const struct btf_var *var_extra; | |
2537 | const char *map_name; | |
2538 | struct bpf_map *map; | |
c7ef5ec9 | 2539 | int err; |
41017e56 AN |
2540 | |
2541 | vi = btf_var_secinfos(sec) + var_idx; | |
2542 | var = btf__type_by_id(obj->btf, vi->type); | |
2543 | var_extra = btf_var(var); | |
2544 | map_name = btf__name_by_offset(obj->btf, var->name_off); | |
2545 | ||
2546 | if (map_name == NULL || map_name[0] == '\0') { | |
2547 | pr_warn("map #%d: empty name.\n", var_idx); | |
2548 | return -EINVAL; | |
2549 | } | |
2550 | if ((__u64)vi->offset + vi->size > data->d_size) { | |
2551 | pr_warn("map '%s' BTF data is corrupted.\n", map_name); | |
2552 | return -EINVAL; | |
2553 | } | |
2554 | if (!btf_is_var(var)) { | |
81ba0889 AN |
2555 | pr_warn("map '%s': unexpected var kind %s.\n", |
2556 | map_name, btf_kind_str(var)); | |
41017e56 AN |
2557 | return -EINVAL; |
2558 | } | |
c1cccec9 AN |
2559 | if (var_extra->linkage != BTF_VAR_GLOBAL_ALLOCATED) { |
2560 | pr_warn("map '%s': unsupported map linkage %s.\n", | |
2561 | map_name, btf_var_linkage_str(var_extra->linkage)); | |
41017e56 AN |
2562 | return -EOPNOTSUPP; |
2563 | } | |
2564 | ||
2565 | def = skip_mods_and_typedefs(obj->btf, var->type, NULL); | |
2566 | if (!btf_is_struct(def)) { | |
81ba0889 AN |
2567 | pr_warn("map '%s': unexpected def kind %s.\n", |
2568 | map_name, btf_kind_str(var)); | |
41017e56 AN |
2569 | return -EINVAL; |
2570 | } | |
2571 | if (def->size > vi->size) { | |
2572 | pr_warn("map '%s': invalid def size.\n", map_name); | |
2573 | return -EINVAL; | |
2574 | } | |
2575 | ||
2576 | map = bpf_object__add_map(obj); | |
2577 | if (IS_ERR(map)) | |
2578 | return PTR_ERR(map); | |
2579 | map->name = strdup(map_name); | |
2580 | if (!map->name) { | |
2581 | pr_warn("map '%s': failed to alloc map name.\n", map_name); | |
2582 | return -ENOMEM; | |
2583 | } | |
2584 | map->libbpf_type = LIBBPF_MAP_UNSPEC; | |
2585 | map->def.type = BPF_MAP_TYPE_UNSPEC; | |
2586 | map->sec_idx = sec_idx; | |
2587 | map->sec_offset = vi->offset; | |
646f02ff | 2588 | map->btf_var_idx = var_idx; |
41017e56 AN |
2589 | pr_debug("map '%s': at sec_idx %d, offset %zu.\n", |
2590 | map_name, map->sec_idx, map->sec_offset); | |
2591 | ||
c7ef5ec9 AN |
2592 | err = parse_btf_map_def(map->name, obj->btf, def, strict, &map_def, &inner_def); |
2593 | if (err) | |
2594 | return err; | |
2595 | ||
2596 | fill_map_from_def(map, &map_def); | |
2597 | ||
2598 | if (map_def.pinning == LIBBPF_PIN_BY_NAME) { | |
2599 | err = build_map_pin_path(map, pin_root_path); | |
2600 | if (err) { | |
2601 | pr_warn("map '%s': couldn't build pin path.\n", map->name); | |
2602 | return err; | |
2603 | } | |
2604 | } | |
2605 | ||
2606 | if (map_def.parts & MAP_DEF_INNER_MAP) { | |
2607 | map->inner_map = calloc(1, sizeof(*map->inner_map)); | |
2608 | if (!map->inner_map) | |
2609 | return -ENOMEM; | |
2610 | map->inner_map->fd = -1; | |
2611 | map->inner_map->sec_idx = sec_idx; | |
2612 | map->inner_map->name = malloc(strlen(map_name) + sizeof(".inner") + 1); | |
2613 | if (!map->inner_map->name) | |
2614 | return -ENOMEM; | |
2615 | sprintf(map->inner_map->name, "%s.inner", map_name); | |
2616 | ||
2617 | fill_map_from_def(map->inner_map, &inner_def); | |
2618 | } | |
2619 | ||
4fcac46c | 2620 | err = map_fill_btf_type_info(obj, map); |
262cfb74 DK |
2621 | if (err) |
2622 | return err; | |
2623 | ||
c7ef5ec9 | 2624 | return 0; |
41017e56 AN |
2625 | } |
2626 | ||
57a00f41 THJ |
2627 | static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict, |
2628 | const char *pin_root_path) | |
abd29c93 AN |
2629 | { |
2630 | const struct btf_type *sec = NULL; | |
2631 | int nr_types, i, vlen, err; | |
2632 | const struct btf_type *t; | |
2633 | const char *name; | |
2634 | Elf_Data *data; | |
2635 | Elf_Scn *scn; | |
2636 | ||
2637 | if (obj->efile.btf_maps_shndx < 0) | |
2638 | return 0; | |
2639 | ||
88a82120 AN |
2640 | scn = elf_sec_by_idx(obj, obj->efile.btf_maps_shndx); |
2641 | data = elf_sec_data(obj, scn); | |
abd29c93 | 2642 | if (!scn || !data) { |
88a82120 AN |
2643 | pr_warn("elf: failed to get %s map definitions for %s\n", |
2644 | MAPS_ELF_SEC, obj->path); | |
abd29c93 AN |
2645 | return -EINVAL; |
2646 | } | |
2647 | ||
6a886de0 HC |
2648 | nr_types = btf__type_cnt(obj->btf); |
2649 | for (i = 1; i < nr_types; i++) { | |
abd29c93 | 2650 | t = btf__type_by_id(obj->btf, i); |
b03bc685 | 2651 | if (!btf_is_datasec(t)) |
abd29c93 AN |
2652 | continue; |
2653 | name = btf__name_by_offset(obj->btf, t->name_off); | |
2654 | if (strcmp(name, MAPS_ELF_SEC) == 0) { | |
2655 | sec = t; | |
646f02ff | 2656 | obj->efile.btf_maps_sec_btf_id = i; |
abd29c93 AN |
2657 | break; |
2658 | } | |
2659 | } | |
2660 | ||
2661 | if (!sec) { | |
be18010e | 2662 | pr_warn("DATASEC '%s' not found.\n", MAPS_ELF_SEC); |
abd29c93 AN |
2663 | return -ENOENT; |
2664 | } | |
2665 | ||
b03bc685 | 2666 | vlen = btf_vlen(sec); |
abd29c93 AN |
2667 | for (i = 0; i < vlen; i++) { |
2668 | err = bpf_object__init_user_btf_map(obj, sec, i, | |
2669 | obj->efile.btf_maps_shndx, | |
8983b731 AN |
2670 | data, strict, |
2671 | pin_root_path); | |
abd29c93 AN |
2672 | if (err) |
2673 | return err; | |
2674 | } | |
2675 | ||
2676 | return 0; | |
2677 | } | |
2678 | ||
0d13bfce | 2679 | static int bpf_object__init_maps(struct bpf_object *obj, |
01af3bf0 | 2680 | const struct bpf_object_open_opts *opts) |
bf829271 | 2681 | { |
166750bc AN |
2682 | const char *pin_root_path; |
2683 | bool strict; | |
bd054102 | 2684 | int err = 0; |
8837fe5d | 2685 | |
166750bc AN |
2686 | strict = !OPTS_GET(opts, relaxed_maps, false); |
2687 | pin_root_path = OPTS_GET(opts, pin_root_path, NULL); | |
bf829271 | 2688 | |
40e1bcab | 2689 | err = bpf_object__init_user_btf_maps(obj, strict, pin_root_path); |
166750bc | 2690 | err = err ?: bpf_object__init_global_data_maps(obj); |
81bfdd08 | 2691 | err = err ?: bpf_object__init_kconfig_map(obj); |
809a69d6 | 2692 | err = err ?: bpf_object_init_struct_ops(obj); |
bf829271 | 2693 | |
3b3af91c | 2694 | return err; |
561bbcca WN |
2695 | } |
2696 | ||
e3d91b0c JDB |
2697 | static bool section_have_execinstr(struct bpf_object *obj, int idx) |
2698 | { | |
ad23b723 | 2699 | Elf64_Shdr *sh; |
e3d91b0c | 2700 | |
ad23b723 AN |
2701 | sh = elf_sec_hdr(obj, elf_sec_by_idx(obj, idx)); |
2702 | if (!sh) | |
e3d91b0c JDB |
2703 | return false; |
2704 | ||
ad23b723 | 2705 | return sh->sh_flags & SHF_EXECINSTR; |
e3d91b0c JDB |
2706 | } |
2707 | ||
0f0e55d8 AN |
2708 | static bool btf_needs_sanitization(struct bpf_object *obj) |
2709 | { | |
9ca1f56a AS |
2710 | bool has_func_global = kernel_supports(obj, FEAT_BTF_GLOBAL_FUNC); |
2711 | bool has_datasec = kernel_supports(obj, FEAT_BTF_DATASEC); | |
2712 | bool has_float = kernel_supports(obj, FEAT_BTF_FLOAT); | |
2713 | bool has_func = kernel_supports(obj, FEAT_BTF_FUNC); | |
223f903e | 2714 | bool has_decl_tag = kernel_supports(obj, FEAT_BTF_DECL_TAG); |
2dc1e488 | 2715 | bool has_type_tag = kernel_supports(obj, FEAT_BTF_TYPE_TAG); |
f2a62588 | 2716 | bool has_enum64 = kernel_supports(obj, FEAT_BTF_ENUM64); |
0f0e55d8 | 2717 | |
2dc1e488 | 2718 | return !has_func || !has_datasec || !has_func_global || !has_float || |
f2a62588 | 2719 | !has_decl_tag || !has_type_tag || !has_enum64; |
0f0e55d8 AN |
2720 | } |
2721 | ||
f2a62588 | 2722 | static int bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf) |
d7c4b398 | 2723 | { |
9ca1f56a AS |
2724 | bool has_func_global = kernel_supports(obj, FEAT_BTF_GLOBAL_FUNC); |
2725 | bool has_datasec = kernel_supports(obj, FEAT_BTF_DATASEC); | |
2726 | bool has_float = kernel_supports(obj, FEAT_BTF_FLOAT); | |
2727 | bool has_func = kernel_supports(obj, FEAT_BTF_FUNC); | |
223f903e | 2728 | bool has_decl_tag = kernel_supports(obj, FEAT_BTF_DECL_TAG); |
2dc1e488 | 2729 | bool has_type_tag = kernel_supports(obj, FEAT_BTF_TYPE_TAG); |
f2a62588 | 2730 | bool has_enum64 = kernel_supports(obj, FEAT_BTF_ENUM64); |
c49a44b3 | 2731 | int enum64_placeholder_id = 0; |
d7c4b398 AN |
2732 | struct btf_type *t; |
2733 | int i, j, vlen; | |
d7c4b398 | 2734 | |
6a886de0 | 2735 | for (i = 1; i < btf__type_cnt(btf); i++) { |
d7c4b398 | 2736 | t = (struct btf_type *)btf__type_by_id(btf, i); |
d7c4b398 | 2737 | |
223f903e YS |
2738 | if ((!has_datasec && btf_is_var(t)) || (!has_decl_tag && btf_is_decl_tag(t))) { |
2739 | /* replace VAR/DECL_TAG with INT */ | |
d7c4b398 | 2740 | t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0); |
1d4126c4 AN |
2741 | /* |
2742 | * using size = 1 is the safest choice, 4 will be too | |
2743 | * big and cause kernel BTF validation failure if | |
2744 | * original variable took less than 4 bytes | |
2745 | */ | |
2746 | t->size = 1; | |
708852dc | 2747 | *(int *)(t + 1) = BTF_INT_ENC(0, 0, 8); |
b03bc685 | 2748 | } else if (!has_datasec && btf_is_datasec(t)) { |
d7c4b398 | 2749 | /* replace DATASEC with STRUCT */ |
b03bc685 AN |
2750 | const struct btf_var_secinfo *v = btf_var_secinfos(t); |
2751 | struct btf_member *m = btf_members(t); | |
d7c4b398 AN |
2752 | struct btf_type *vt; |
2753 | char *name; | |
2754 | ||
2755 | name = (char *)btf__name_by_offset(btf, t->name_off); | |
2756 | while (*name) { | |
2757 | if (*name == '.') | |
2758 | *name = '_'; | |
2759 | name++; | |
2760 | } | |
2761 | ||
b03bc685 | 2762 | vlen = btf_vlen(t); |
d7c4b398 AN |
2763 | t->info = BTF_INFO_ENC(BTF_KIND_STRUCT, 0, vlen); |
2764 | for (j = 0; j < vlen; j++, v++, m++) { | |
2765 | /* order of field assignments is important */ | |
2766 | m->offset = v->offset * 8; | |
2767 | m->type = v->type; | |
2768 | /* preserve variable name as member name */ | |
2769 | vt = (void *)btf__type_by_id(btf, v->type); | |
2770 | m->name_off = vt->name_off; | |
2771 | } | |
b03bc685 | 2772 | } else if (!has_func && btf_is_func_proto(t)) { |
d7c4b398 | 2773 | /* replace FUNC_PROTO with ENUM */ |
b03bc685 | 2774 | vlen = btf_vlen(t); |
d7c4b398 AN |
2775 | t->info = BTF_INFO_ENC(BTF_KIND_ENUM, 0, vlen); |
2776 | t->size = sizeof(__u32); /* kernel enforced */ | |
b03bc685 | 2777 | } else if (!has_func && btf_is_func(t)) { |
d7c4b398 AN |
2778 | /* replace FUNC with TYPEDEF */ |
2779 | t->info = BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0); | |
2d3eb67f AS |
2780 | } else if (!has_func_global && btf_is_func(t)) { |
2781 | /* replace BTF_FUNC_GLOBAL with BTF_FUNC_STATIC */ | |
2782 | t->info = BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0); | |
22541a9e IL |
2783 | } else if (!has_float && btf_is_float(t)) { |
2784 | /* replace FLOAT with an equally-sized empty STRUCT; | |
2785 | * since C compilers do not accept e.g. "float" as a | |
2786 | * valid struct name, make it anonymous | |
2787 | */ | |
2788 | t->name_off = 0; | |
2789 | t->info = BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 0); | |
2dc1e488 YS |
2790 | } else if (!has_type_tag && btf_is_type_tag(t)) { |
2791 | /* replace TYPE_TAG with a CONST */ | |
2792 | t->name_off = 0; | |
2793 | t->info = BTF_INFO_ENC(BTF_KIND_CONST, 0, 0); | |
f2a62588 YS |
2794 | } else if (!has_enum64 && btf_is_enum(t)) { |
2795 | /* clear the kflag */ | |
2796 | t->info = btf_type_info(btf_kind(t), btf_vlen(t), false); | |
2797 | } else if (!has_enum64 && btf_is_enum64(t)) { | |
2798 | /* replace ENUM64 with a union */ | |
2799 | struct btf_member *m; | |
2800 | ||
2801 | if (enum64_placeholder_id == 0) { | |
2802 | enum64_placeholder_id = btf__add_int(btf, "enum64_placeholder", 1, 0); | |
2803 | if (enum64_placeholder_id < 0) | |
2804 | return enum64_placeholder_id; | |
2805 | ||
2806 | t = (struct btf_type *)btf__type_by_id(btf, i); | |
2807 | } | |
2808 | ||
2809 | m = btf_members(t); | |
2810 | vlen = btf_vlen(t); | |
2811 | t->info = BTF_INFO_ENC(BTF_KIND_UNION, 0, vlen); | |
2812 | for (j = 0; j < vlen; j++, m++) { | |
2813 | m->type = enum64_placeholder_id; | |
2814 | m->offset = 0; | |
2815 | } | |
e3ba8e4e | 2816 | } |
d7c4b398 | 2817 | } |
f2a62588 YS |
2818 | |
2819 | return 0; | |
d7c4b398 AN |
2820 | } |
2821 | ||
b35f14f4 | 2822 | static bool libbpf_needs_btf(const struct bpf_object *obj) |
abd29c93 | 2823 | { |
b35f14f4 AN |
2824 | return obj->efile.btf_maps_shndx >= 0 || |
2825 | obj->efile.st_ops_shndx >= 0 || | |
809a69d6 | 2826 | obj->efile.st_ops_link_shndx >= 0 || |
b35f14f4 AN |
2827 | obj->nr_extern > 0; |
2828 | } | |
2829 | ||
2830 | static bool kernel_needs_btf(const struct bpf_object *obj) | |
2831 | { | |
809a69d6 | 2832 | return obj->efile.st_ops_shndx >= 0 || obj->efile.st_ops_link_shndx >= 0; |
abd29c93 AN |
2833 | } |
2834 | ||
063183bf | 2835 | static int bpf_object__init_btf(struct bpf_object *obj, |
9c6660d0 AN |
2836 | Elf_Data *btf_data, |
2837 | Elf_Data *btf_ext_data) | |
2838 | { | |
b7d7f3e1 | 2839 | int err = -ENOENT; |
9c6660d0 AN |
2840 | |
2841 | if (btf_data) { | |
2842 | obj->btf = btf__new(btf_data->d_buf, btf_data->d_size); | |
e9fc3ce9 AN |
2843 | err = libbpf_get_error(obj->btf); |
2844 | if (err) { | |
b7d7f3e1 | 2845 | obj->btf = NULL; |
e9fc3ce9 | 2846 | pr_warn("Error loading ELF section %s: %d.\n", BTF_ELF_SEC, err); |
9c6660d0 AN |
2847 | goto out; |
2848 | } | |
4c01925f AN |
2849 | /* enforce 8-byte pointers for BPF-targeted BTFs */ |
2850 | btf__set_pointer_size(obj->btf, 8); | |
9c6660d0 AN |
2851 | } |
2852 | if (btf_ext_data) { | |
11d5daa8 AN |
2853 | struct btf_ext_info *ext_segs[3]; |
2854 | int seg_num, sec_num; | |
2855 | ||
9c6660d0 AN |
2856 | if (!obj->btf) { |
2857 | pr_debug("Ignore ELF section %s because its depending ELF section %s is not found.\n", | |
2858 | BTF_EXT_ELF_SEC, BTF_ELF_SEC); | |
2859 | goto out; | |
2860 | } | |
e9fc3ce9 AN |
2861 | obj->btf_ext = btf_ext__new(btf_ext_data->d_buf, btf_ext_data->d_size); |
2862 | err = libbpf_get_error(obj->btf_ext); | |
2863 | if (err) { | |
2864 | pr_warn("Error loading ELF section %s: %d. Ignored and continue.\n", | |
2865 | BTF_EXT_ELF_SEC, err); | |
9c6660d0 AN |
2866 | obj->btf_ext = NULL; |
2867 | goto out; | |
2868 | } | |
11d5daa8 AN |
2869 | |
2870 | /* setup .BTF.ext to ELF section mapping */ | |
2871 | ext_segs[0] = &obj->btf_ext->func_info; | |
2872 | ext_segs[1] = &obj->btf_ext->line_info; | |
2873 | ext_segs[2] = &obj->btf_ext->core_relo_info; | |
2874 | for (seg_num = 0; seg_num < ARRAY_SIZE(ext_segs); seg_num++) { | |
2875 | struct btf_ext_info *seg = ext_segs[seg_num]; | |
2876 | const struct btf_ext_info_sec *sec; | |
2877 | const char *sec_name; | |
2878 | Elf_Scn *scn; | |
2879 | ||
2880 | if (seg->sec_cnt == 0) | |
2881 | continue; | |
2882 | ||
2883 | seg->sec_idxs = calloc(seg->sec_cnt, sizeof(*seg->sec_idxs)); | |
2884 | if (!seg->sec_idxs) { | |
2885 | err = -ENOMEM; | |
2886 | goto out; | |
2887 | } | |
2888 | ||
2889 | sec_num = 0; | |
2890 | for_each_btf_ext_sec(seg, sec) { | |
2891 | /* preventively increment index to avoid doing | |
2892 | * this before every continue below | |
2893 | */ | |
2894 | sec_num++; | |
2895 | ||
2896 | sec_name = btf__name_by_offset(obj->btf, sec->sec_name_off); | |
2897 | if (str_is_empty(sec_name)) | |
2898 | continue; | |
2899 | scn = elf_sec_by_name(obj, sec_name); | |
2900 | if (!scn) | |
2901 | continue; | |
2902 | ||
2903 | seg->sec_idxs[sec_num - 1] = elf_ndxscn(scn); | |
2904 | } | |
2905 | } | |
9c6660d0 AN |
2906 | } |
2907 | out: | |
b35f14f4 | 2908 | if (err && libbpf_needs_btf(obj)) { |
be18010e | 2909 | pr_warn("BTF is required, but is missing or corrupted.\n"); |
b7d7f3e1 | 2910 | return err; |
abd29c93 | 2911 | } |
9c6660d0 AN |
2912 | return 0; |
2913 | } | |
2914 | ||
b96c07f3 AN |
2915 | static int compare_vsi_off(const void *_a, const void *_b) |
2916 | { | |
2917 | const struct btf_var_secinfo *a = _a; | |
2918 | const struct btf_var_secinfo *b = _b; | |
2919 | ||
2920 | return a->offset - b->offset; | |
2921 | } | |
2922 | ||
2923 | static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf, | |
2924 | struct btf_type *t) | |
2925 | { | |
f33f742d AN |
2926 | __u32 size = 0, i, vars = btf_vlen(t); |
2927 | const char *sec_name = btf__name_by_offset(btf, t->name_off); | |
b96c07f3 | 2928 | struct btf_var_secinfo *vsi; |
4fcac46c | 2929 | bool fixup_offsets = false; |
f33f742d | 2930 | int err; |
b96c07f3 | 2931 | |
f33f742d | 2932 | if (!sec_name) { |
b96c07f3 AN |
2933 | pr_debug("No name found in string section for DATASEC kind.\n"); |
2934 | return -ENOENT; | |
2935 | } | |
2936 | ||
4fcac46c AN |
2937 | /* Extern-backing datasecs (.ksyms, .kconfig) have their size and |
2938 | * variable offsets set at the previous step. Further, not every | |
2939 | * extern BTF VAR has corresponding ELF symbol preserved, so we skip | |
2940 | * all fixups altogether for such sections and go straight to sorting | |
2941 | * VARs within their DATASEC. | |
b96c07f3 | 2942 | */ |
4fcac46c | 2943 | if (strcmp(sec_name, KCONFIG_SEC) == 0 || strcmp(sec_name, KSYMS_SEC) == 0) |
b96c07f3 AN |
2944 | goto sort_vars; |
2945 | ||
4fcac46c AN |
2946 | /* Clang leaves DATASEC size and VAR offsets as zeroes, so we need to |
2947 | * fix this up. But BPF static linker already fixes this up and fills | |
2948 | * all the sizes and offsets during static linking. So this step has | |
2949 | * to be optional. But the STV_HIDDEN handling is non-optional for any | |
2950 | * non-extern DATASEC, so the variable fixup loop below handles both | |
2951 | * functions at the same time, paying the cost of BTF VAR <-> ELF | |
2952 | * symbol matching just once. | |
2953 | */ | |
2954 | if (t->size == 0) { | |
2955 | err = find_elf_sec_sz(obj, sec_name, &size); | |
2956 | if (err || !size) { | |
2957 | pr_debug("sec '%s': failed to determine size from ELF: size %u, err %d\n", | |
2958 | sec_name, size, err); | |
2959 | return -ENOENT; | |
2960 | } | |
b96c07f3 | 2961 | |
4fcac46c AN |
2962 | t->size = size; |
2963 | fixup_offsets = true; | |
2964 | } | |
b96c07f3 AN |
2965 | |
2966 | for (i = 0, vsi = btf_var_secinfos(t); i < vars; i++, vsi++) { | |
f33f742d AN |
2967 | const struct btf_type *t_var; |
2968 | struct btf_var *var; | |
2969 | const char *var_name; | |
2970 | Elf64_Sym *sym; | |
2971 | ||
b96c07f3 | 2972 | t_var = btf__type_by_id(btf, vsi->type); |
88918dc1 | 2973 | if (!t_var || !btf_is_var(t_var)) { |
f33f742d | 2974 | pr_debug("sec '%s': unexpected non-VAR type found\n", sec_name); |
b96c07f3 AN |
2975 | return -EINVAL; |
2976 | } | |
2977 | ||
88918dc1 | 2978 | var = btf_var(t_var); |
f33f742d | 2979 | if (var->linkage == BTF_VAR_STATIC || var->linkage == BTF_VAR_GLOBAL_EXTERN) |
b96c07f3 AN |
2980 | continue; |
2981 | ||
f33f742d AN |
2982 | var_name = btf__name_by_offset(btf, t_var->name_off); |
2983 | if (!var_name) { | |
2984 | pr_debug("sec '%s': failed to find name of DATASEC's member #%d\n", | |
2985 | sec_name, i); | |
b96c07f3 AN |
2986 | return -ENOENT; |
2987 | } | |
2988 | ||
f33f742d AN |
2989 | sym = find_elf_var_sym(obj, var_name); |
2990 | if (IS_ERR(sym)) { | |
2991 | pr_debug("sec '%s': failed to find ELF symbol for VAR '%s'\n", | |
2992 | sec_name, var_name); | |
b96c07f3 AN |
2993 | return -ENOENT; |
2994 | } | |
2995 | ||
4fcac46c AN |
2996 | if (fixup_offsets) |
2997 | vsi->offset = sym->st_value; | |
2998 | ||
2999 | /* if variable is a global/weak symbol, but has restricted | |
3000 | * (STV_HIDDEN or STV_INTERNAL) visibility, mark its BTF VAR | |
3001 | * as static. This follows similar logic for functions (BPF | |
3002 | * subprogs) and influences libbpf's further decisions about | |
3003 | * whether to make global data BPF array maps as | |
3004 | * BPF_F_MMAPABLE. | |
3005 | */ | |
3006 | if (ELF64_ST_VISIBILITY(sym->st_other) == STV_HIDDEN | |
3007 | || ELF64_ST_VISIBILITY(sym->st_other) == STV_INTERNAL) | |
3008 | var->linkage = BTF_VAR_STATIC; | |
b96c07f3 AN |
3009 | } |
3010 | ||
3011 | sort_vars: | |
3012 | qsort(btf_var_secinfos(t), vars, sizeof(*vsi), compare_vsi_off); | |
3013 | return 0; | |
3014 | } | |
3015 | ||
f33f742d | 3016 | static int bpf_object_fixup_btf(struct bpf_object *obj) |
b96c07f3 | 3017 | { |
f33f742d | 3018 | int i, n, err = 0; |
b96c07f3 | 3019 | |
f33f742d AN |
3020 | if (!obj->btf) |
3021 | return 0; | |
3022 | ||
3023 | n = btf__type_cnt(obj->btf); | |
6a886de0 | 3024 | for (i = 1; i < n; i++) { |
f33f742d | 3025 | struct btf_type *t = btf_type_by_id(obj->btf, i); |
b96c07f3 AN |
3026 | |
3027 | /* Loader needs to fix up some of the things compiler | |
3028 | * couldn't get its hands on while emitting BTF. This | |
3029 | * is section size and global variable offset. We use | |
3030 | * the info from the ELF itself for this purpose. | |
3031 | */ | |
3032 | if (btf_is_datasec(t)) { | |
f33f742d | 3033 | err = btf_fixup_datasec(obj, obj->btf, t); |
b96c07f3 | 3034 | if (err) |
f33f742d | 3035 | return err; |
b96c07f3 AN |
3036 | } |
3037 | } | |
3038 | ||
166750bc AN |
3039 | return 0; |
3040 | } | |
3041 | ||
fe62de31 | 3042 | static bool prog_needs_vmlinux_btf(struct bpf_program *prog) |
a6ed02ca | 3043 | { |
1e092a03 KS |
3044 | if (prog->type == BPF_PROG_TYPE_STRUCT_OPS || |
3045 | prog->type == BPF_PROG_TYPE_LSM) | |
a6ed02ca KS |
3046 | return true; |
3047 | ||
3048 | /* BPF_PROG_TYPE_TRACING programs which do not attach to other programs | |
3049 | * also need vmlinux BTF | |
3050 | */ | |
3051 | if (prog->type == BPF_PROG_TYPE_TRACING && !prog->attach_prog_fd) | |
3052 | return true; | |
3053 | ||
3054 | return false; | |
3055 | } | |
3056 | ||
fe62de31 | 3057 | static bool obj_needs_vmlinux_btf(const struct bpf_object *obj) |
a6ed02ca KS |
3058 | { |
3059 | struct bpf_program *prog; | |
fe62de31 | 3060 | int i; |
a6ed02ca | 3061 | |
1373ff59 SC |
3062 | /* CO-RE relocations need kernel BTF, only when btf_custom_path |
3063 | * is not specified | |
3064 | */ | |
3065 | if (obj->btf_ext && obj->btf_ext->core_relo_info.len && !obj->btf_custom_path) | |
fe62de31 | 3066 | return true; |
192b6638 | 3067 | |
d370bbe1 HL |
3068 | /* Support for typed ksyms needs kernel BTF */ |
3069 | for (i = 0; i < obj->nr_extern; i++) { | |
3070 | const struct extern_desc *ext; | |
3071 | ||
3072 | ext = &obj->externs[i]; | |
fe62de31 AN |
3073 | if (ext->type == EXT_KSYM && ext->ksym.type_id) |
3074 | return true; | |
d370bbe1 HL |
3075 | } |
3076 | ||
a6ed02ca | 3077 | bpf_object__for_each_program(prog, obj) { |
a3820c48 | 3078 | if (!prog->autoload) |
d9297581 | 3079 | continue; |
fe62de31 AN |
3080 | if (prog_needs_vmlinux_btf(prog)) |
3081 | return true; | |
a6ed02ca KS |
3082 | } |
3083 | ||
fe62de31 AN |
3084 | return false; |
3085 | } | |
3086 | ||
3087 | static int bpf_object__load_vmlinux_btf(struct bpf_object *obj, bool force) | |
3088 | { | |
3089 | int err; | |
3090 | ||
3091 | /* btf_vmlinux could be loaded earlier */ | |
67234743 | 3092 | if (obj->btf_vmlinux || obj->gen_loader) |
fe62de31 AN |
3093 | return 0; |
3094 | ||
3095 | if (!force && !obj_needs_vmlinux_btf(obj)) | |
192b6638 AN |
3096 | return 0; |
3097 | ||
a710eed3 | 3098 | obj->btf_vmlinux = btf__load_vmlinux_btf(); |
e9fc3ce9 AN |
3099 | err = libbpf_get_error(obj->btf_vmlinux); |
3100 | if (err) { | |
192b6638 AN |
3101 | pr_warn("Error loading vmlinux BTF: %d\n", err); |
3102 | obj->btf_vmlinux = NULL; | |
3103 | return err; | |
3104 | } | |
a6ed02ca KS |
3105 | return 0; |
3106 | } | |
3107 | ||
063183bf AN |
3108 | static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) |
3109 | { | |
0f0e55d8 AN |
3110 | struct btf *kern_btf = obj->btf; |
3111 | bool btf_mandatory, sanitize; | |
aea28a60 | 3112 | int i, err = 0; |
063183bf AN |
3113 | |
3114 | if (!obj->btf) | |
3115 | return 0; | |
3116 | ||
9ca1f56a | 3117 | if (!kernel_supports(obj, FEAT_BTF)) { |
68b08647 AN |
3118 | if (kernel_needs_btf(obj)) { |
3119 | err = -EOPNOTSUPP; | |
3120 | goto report; | |
3121 | } | |
3122 | pr_debug("Kernel doesn't support BTF, skipping uploading it.\n"); | |
3123 | return 0; | |
3124 | } | |
3125 | ||
aea28a60 AN |
3126 | /* Even though some subprogs are global/weak, user might prefer more |
3127 | * permissive BPF verification process that BPF verifier performs for | |
3128 | * static functions, taking into account more context from the caller | |
3129 | * functions. In such case, they need to mark such subprogs with | |
3130 | * __attribute__((visibility("hidden"))) and libbpf will adjust | |
3131 | * corresponding FUNC BTF type to be marked as static and trigger more | |
3132 | * involved BPF verification process. | |
3133 | */ | |
3134 | for (i = 0; i < obj->nr_programs; i++) { | |
3135 | struct bpf_program *prog = &obj->programs[i]; | |
3136 | struct btf_type *t; | |
3137 | const char *name; | |
3138 | int j, n; | |
3139 | ||
3140 | if (!prog->mark_btf_static || !prog_is_subprog(obj, prog)) | |
3141 | continue; | |
3142 | ||
6a886de0 HC |
3143 | n = btf__type_cnt(obj->btf); |
3144 | for (j = 1; j < n; j++) { | |
aea28a60 AN |
3145 | t = btf_type_by_id(obj->btf, j); |
3146 | if (!btf_is_func(t) || btf_func_linkage(t) != BTF_FUNC_GLOBAL) | |
3147 | continue; | |
3148 | ||
3149 | name = btf__str_by_offset(obj->btf, t->name_off); | |
3150 | if (strcmp(name, prog->name) != 0) | |
3151 | continue; | |
3152 | ||
3153 | t->info = btf_type_info(BTF_KIND_FUNC, BTF_FUNC_STATIC, 0); | |
3154 | break; | |
3155 | } | |
3156 | } | |
3157 | ||
7e2925f6 KKD |
3158 | if (!kernel_supports(obj, FEAT_BTF_DECL_TAG)) |
3159 | goto skip_exception_cb; | |
3160 | for (i = 0; i < obj->nr_programs; i++) { | |
3161 | struct bpf_program *prog = &obj->programs[i]; | |
3162 | int j, k, n; | |
3163 | ||
3164 | if (prog_is_subprog(obj, prog)) | |
3165 | continue; | |
3166 | n = btf__type_cnt(obj->btf); | |
3167 | for (j = 1; j < n; j++) { | |
3168 | const char *str = "exception_callback:", *name; | |
3169 | size_t len = strlen(str); | |
3170 | struct btf_type *t; | |
3171 | ||
3172 | t = btf_type_by_id(obj->btf, j); | |
3173 | if (!btf_is_decl_tag(t) || btf_decl_tag(t)->component_idx != -1) | |
3174 | continue; | |
3175 | ||
3176 | name = btf__str_by_offset(obj->btf, t->name_off); | |
3177 | if (strncmp(name, str, len)) | |
3178 | continue; | |
3179 | ||
3180 | t = btf_type_by_id(obj->btf, t->type); | |
3181 | if (!btf_is_func(t) || btf_func_linkage(t) != BTF_FUNC_GLOBAL) { | |
3182 | pr_warn("prog '%s': exception_callback:<value> decl tag not applied to the main program\n", | |
3183 | prog->name); | |
3184 | return -EINVAL; | |
3185 | } | |
3186 | if (strcmp(prog->name, btf__str_by_offset(obj->btf, t->name_off))) | |
3187 | continue; | |
3188 | /* Multiple callbacks are specified for the same prog, | |
3189 | * the verifier will eventually return an error for this | |
3190 | * case, hence simply skip appending a subprog. | |
3191 | */ | |
3192 | if (prog->exception_cb_idx >= 0) { | |
3193 | prog->exception_cb_idx = -1; | |
3194 | break; | |
3195 | } | |
3196 | ||
3197 | name += len; | |
3198 | if (str_is_empty(name)) { | |
3199 | pr_warn("prog '%s': exception_callback:<value> decl tag contains empty value\n", | |
3200 | prog->name); | |
3201 | return -EINVAL; | |
3202 | } | |
3203 | ||
3204 | for (k = 0; k < obj->nr_programs; k++) { | |
3205 | struct bpf_program *subprog = &obj->programs[k]; | |
3206 | ||
3207 | if (!prog_is_subprog(obj, subprog)) | |
3208 | continue; | |
3209 | if (strcmp(name, subprog->name)) | |
3210 | continue; | |
3211 | /* Enforce non-hidden, as from verifier point of | |
3212 | * view it expects global functions, whereas the | |
3213 | * mark_btf_static fixes up linkage as static. | |
3214 | */ | |
3215 | if (!subprog->sym_global || subprog->mark_btf_static) { | |
3216 | pr_warn("prog '%s': exception callback %s must be a global non-hidden function\n", | |
3217 | prog->name, subprog->name); | |
3218 | return -EINVAL; | |
3219 | } | |
3220 | /* Let's see if we already saw a static exception callback with the same name */ | |
3221 | if (prog->exception_cb_idx >= 0) { | |
3222 | pr_warn("prog '%s': multiple subprogs with same name as exception callback '%s'\n", | |
3223 | prog->name, subprog->name); | |
3224 | return -EINVAL; | |
3225 | } | |
3226 | prog->exception_cb_idx = k; | |
3227 | break; | |
3228 | } | |
3229 | ||
3230 | if (prog->exception_cb_idx >= 0) | |
3231 | continue; | |
3232 | pr_warn("prog '%s': cannot find exception callback '%s'\n", prog->name, name); | |
3233 | return -ENOENT; | |
3234 | } | |
3235 | } | |
3236 | skip_exception_cb: | |
3237 | ||
0f0e55d8 AN |
3238 | sanitize = btf_needs_sanitization(obj); |
3239 | if (sanitize) { | |
5c3320d7 | 3240 | const void *raw_data; |
0f0e55d8 | 3241 | __u32 sz; |
063183bf | 3242 | |
0f0e55d8 | 3243 | /* clone BTF to sanitize a copy and leave the original intact */ |
6a886de0 | 3244 | raw_data = btf__raw_data(obj->btf, &sz); |
5c3320d7 | 3245 | kern_btf = btf__new(raw_data, sz); |
e9fc3ce9 AN |
3246 | err = libbpf_get_error(kern_btf); |
3247 | if (err) | |
3248 | return err; | |
04efe591 | 3249 | |
4c01925f AN |
3250 | /* enforce 8-byte pointers for BPF-targeted BTFs */ |
3251 | btf__set_pointer_size(obj->btf, 8); | |
f2a62588 YS |
3252 | err = bpf_object__sanitize_btf(obj, kern_btf); |
3253 | if (err) | |
3254 | return err; | |
063183bf | 3255 | } |
0f0e55d8 | 3256 | |
67234743 AS |
3257 | if (obj->gen_loader) { |
3258 | __u32 raw_size = 0; | |
6a886de0 | 3259 | const void *raw_data = btf__raw_data(kern_btf, &raw_size); |
67234743 AS |
3260 | |
3261 | if (!raw_data) | |
3262 | return -ENOMEM; | |
3263 | bpf_gen__load_btf(obj->gen_loader, raw_data, raw_size); | |
3264 | /* Pretend to have valid FD to pass various fd >= 0 checks. | |
3265 | * This fd == 0 will not be used with any syscall and will be reset to -1 eventually. | |
3266 | */ | |
3267 | btf__set_fd(kern_btf, 0); | |
3268 | } else { | |
e0e3ea88 AN |
3269 | /* currently BPF_BTF_LOAD only supports log_level 1 */ |
3270 | err = btf_load_into_kernel(kern_btf, obj->log_buf, obj->log_size, | |
3271 | obj->log_level ? 1 : 0); | |
67234743 | 3272 | } |
0f0e55d8 AN |
3273 | if (sanitize) { |
3274 | if (!err) { | |
3275 | /* move fd to libbpf's BTF */ | |
3276 | btf__set_fd(obj->btf, btf__fd(kern_btf)); | |
3277 | btf__set_fd(kern_btf, -1); | |
3278 | } | |
3279 | btf__free(kern_btf); | |
3280 | } | |
68b08647 | 3281 | report: |
0f0e55d8 AN |
3282 | if (err) { |
3283 | btf_mandatory = kernel_needs_btf(obj); | |
3284 | pr_warn("Error loading .BTF into kernel: %d. %s\n", err, | |
3285 | btf_mandatory ? "BTF is mandatory, can't proceed." | |
3286 | : "BTF is optional, ignoring."); | |
3287 | if (!btf_mandatory) | |
3288 | err = 0; | |
3289 | } | |
3290 | return err; | |
063183bf AN |
3291 | } |
3292 | ||
88a82120 AN |
3293 | static const char *elf_sym_str(const struct bpf_object *obj, size_t off) |
3294 | { | |
3295 | const char *name; | |
3296 | ||
3297 | name = elf_strptr(obj->efile.elf, obj->efile.strtabidx, off); | |
3298 | if (!name) { | |
3299 | pr_warn("elf: failed to get section name string at offset %zu from %s: %s\n", | |
3300 | off, obj->path, elf_errmsg(-1)); | |
3301 | return NULL; | |
3302 | } | |
3303 | ||
3304 | return name; | |
3305 | } | |
3306 | ||
3307 | static const char *elf_sec_str(const struct bpf_object *obj, size_t off) | |
3308 | { | |
3309 | const char *name; | |
3310 | ||
3311 | name = elf_strptr(obj->efile.elf, obj->efile.shstrndx, off); | |
3312 | if (!name) { | |
3313 | pr_warn("elf: failed to get section name string at offset %zu from %s: %s\n", | |
3314 | off, obj->path, elf_errmsg(-1)); | |
3315 | return NULL; | |
3316 | } | |
3317 | ||
3318 | return name; | |
3319 | } | |
3320 | ||
3321 | static Elf_Scn *elf_sec_by_idx(const struct bpf_object *obj, size_t idx) | |
3322 | { | |
3323 | Elf_Scn *scn; | |
3324 | ||
3325 | scn = elf_getscn(obj->efile.elf, idx); | |
3326 | if (!scn) { | |
3327 | pr_warn("elf: failed to get section(%zu) from %s: %s\n", | |
3328 | idx, obj->path, elf_errmsg(-1)); | |
3329 | return NULL; | |
3330 | } | |
3331 | return scn; | |
3332 | } | |
3333 | ||
3334 | static Elf_Scn *elf_sec_by_name(const struct bpf_object *obj, const char *name) | |
3335 | { | |
3336 | Elf_Scn *scn = NULL; | |
3337 | Elf *elf = obj->efile.elf; | |
3338 | const char *sec_name; | |
3339 | ||
3340 | while ((scn = elf_nextscn(elf, scn)) != NULL) { | |
3341 | sec_name = elf_sec_name(obj, scn); | |
3342 | if (!sec_name) | |
3343 | return NULL; | |
3344 | ||
3345 | if (strcmp(sec_name, name) != 0) | |
3346 | continue; | |
3347 | ||
3348 | return scn; | |
3349 | } | |
3350 | return NULL; | |
3351 | } | |
3352 | ||
ad23b723 | 3353 | static Elf64_Shdr *elf_sec_hdr(const struct bpf_object *obj, Elf_Scn *scn) |
88a82120 | 3354 | { |
ad23b723 AN |
3355 | Elf64_Shdr *shdr; |
3356 | ||
88a82120 | 3357 | if (!scn) |
ad23b723 | 3358 | return NULL; |
88a82120 | 3359 | |
ad23b723 AN |
3360 | shdr = elf64_getshdr(scn); |
3361 | if (!shdr) { | |
88a82120 AN |
3362 | pr_warn("elf: failed to get section(%zu) header from %s: %s\n", |
3363 | elf_ndxscn(scn), obj->path, elf_errmsg(-1)); | |
ad23b723 | 3364 | return NULL; |
88a82120 AN |
3365 | } |
3366 | ||
ad23b723 | 3367 | return shdr; |
88a82120 AN |
3368 | } |
3369 | ||
3370 | static const char *elf_sec_name(const struct bpf_object *obj, Elf_Scn *scn) | |
3371 | { | |
3372 | const char *name; | |
ad23b723 | 3373 | Elf64_Shdr *sh; |
88a82120 AN |
3374 | |
3375 | if (!scn) | |
3376 | return NULL; | |
3377 | ||
ad23b723 AN |
3378 | sh = elf_sec_hdr(obj, scn); |
3379 | if (!sh) | |
88a82120 AN |
3380 | return NULL; |
3381 | ||
ad23b723 | 3382 | name = elf_sec_str(obj, sh->sh_name); |
88a82120 AN |
3383 | if (!name) { |
3384 | pr_warn("elf: failed to get section(%zu) name from %s: %s\n", | |
3385 | elf_ndxscn(scn), obj->path, elf_errmsg(-1)); | |
3386 | return NULL; | |
3387 | } | |
3388 | ||
3389 | return name; | |
3390 | } | |
3391 | ||
3392 | static Elf_Data *elf_sec_data(const struct bpf_object *obj, Elf_Scn *scn) | |
3393 | { | |
3394 | Elf_Data *data; | |
3395 | ||
3396 | if (!scn) | |
3397 | return NULL; | |
3398 | ||
3399 | data = elf_getdata(scn, 0); | |
3400 | if (!data) { | |
3401 | pr_warn("elf: failed to get section(%zu) %s data from %s: %s\n", | |
3402 | elf_ndxscn(scn), elf_sec_name(obj, scn) ?: "<?>", | |
3403 | obj->path, elf_errmsg(-1)); | |
3404 | return NULL; | |
3405 | } | |
3406 | ||
3407 | return data; | |
3408 | } | |
3409 | ||
ad23b723 AN |
3410 | static Elf64_Sym *elf_sym_by_idx(const struct bpf_object *obj, size_t idx) |
3411 | { | |
3412 | if (idx >= obj->efile.symbols->d_size / sizeof(Elf64_Sym)) | |
3413 | return NULL; | |
3414 | ||
3415 | return (Elf64_Sym *)obj->efile.symbols->d_buf + idx; | |
3416 | } | |
3417 | ||
3418 | static Elf64_Rel *elf_rel_by_idx(Elf_Data *data, size_t idx) | |
3419 | { | |
3420 | if (idx >= data->d_size / sizeof(Elf64_Rel)) | |
3421 | return NULL; | |
3422 | ||
3423 | return (Elf64_Rel *)data->d_buf + idx; | |
3424 | } | |
3425 | ||
50e09460 AN |
3426 | static bool is_sec_name_dwarf(const char *name) |
3427 | { | |
3428 | /* approximation, but the actual list is too long */ | |
13d35a0c | 3429 | return str_has_pfx(name, ".debug_"); |
50e09460 AN |
3430 | } |
3431 | ||
ad23b723 | 3432 | static bool ignore_elf_section(Elf64_Shdr *hdr, const char *name) |
50e09460 AN |
3433 | { |
3434 | /* no special handling of .strtab */ | |
3435 | if (hdr->sh_type == SHT_STRTAB) | |
3436 | return true; | |
3437 | ||
3438 | /* ignore .llvm_addrsig section as well */ | |
faf6ed32 | 3439 | if (hdr->sh_type == SHT_LLVM_ADDRSIG) |
50e09460 AN |
3440 | return true; |
3441 | ||
3442 | /* no subprograms will lead to an empty .text section, ignore it */ | |
3443 | if (hdr->sh_type == SHT_PROGBITS && hdr->sh_size == 0 && | |
3444 | strcmp(name, ".text") == 0) | |
3445 | return true; | |
3446 | ||
3447 | /* DWARF sections */ | |
3448 | if (is_sec_name_dwarf(name)) | |
3449 | return true; | |
3450 | ||
13d35a0c | 3451 | if (str_has_pfx(name, ".rel")) { |
50e09460 AN |
3452 | name += sizeof(".rel") - 1; |
3453 | /* DWARF section relocations */ | |
3454 | if (is_sec_name_dwarf(name)) | |
3455 | return true; | |
3456 | ||
3457 | /* .BTF and .BTF.ext don't need relocations */ | |
3458 | if (strcmp(name, BTF_ELF_SEC) == 0 || | |
3459 | strcmp(name, BTF_EXT_ELF_SEC) == 0) | |
3460 | return true; | |
3461 | } | |
3462 | ||
3463 | return false; | |
3464 | } | |
3465 | ||
db2b8b06 AN |
3466 | static int cmp_progs(const void *_a, const void *_b) |
3467 | { | |
3468 | const struct bpf_program *a = _a; | |
3469 | const struct bpf_program *b = _b; | |
3470 | ||
3471 | if (a->sec_idx != b->sec_idx) | |
3472 | return a->sec_idx < b->sec_idx ? -1 : 1; | |
3473 | ||
3474 | /* sec_insn_off can't be the same within the section */ | |
3475 | return a->sec_insn_off < b->sec_insn_off ? -1 : 1; | |
3476 | } | |
3477 | ||
0d13bfce | 3478 | static int bpf_object__elf_collect(struct bpf_object *obj) |
29603665 | 3479 | { |
25bbbd7a | 3480 | struct elf_sec_desc *sec_desc; |
29603665 | 3481 | Elf *elf = obj->efile.elf; |
f0187f0b | 3482 | Elf_Data *btf_ext_data = NULL; |
1713d68b | 3483 | Elf_Data *btf_data = NULL; |
666810e8 | 3484 | int idx = 0, err = 0; |
0201c575 AN |
3485 | const char *name; |
3486 | Elf_Data *data; | |
3487 | Elf_Scn *scn; | |
ad23b723 | 3488 | Elf64_Shdr *sh; |
29603665 | 3489 | |
0d6988e1 | 3490 | /* ELF section indices are 0-based, but sec #0 is special "invalid" |
51deedc9 SHY |
3491 | * section. Since section count retrieved by elf_getshdrnum() does |
3492 | * include sec #0, it is already the necessary size of an array to keep | |
3493 | * all the sections. | |
25bbbd7a | 3494 | */ |
51deedc9 SHY |
3495 | if (elf_getshdrnum(obj->efile.elf, &obj->efile.sec_cnt)) { |
3496 | pr_warn("elf: failed to get the number of sections for %s: %s\n", | |
3497 | obj->path, elf_errmsg(-1)); | |
3498 | return -LIBBPF_ERRNO__FORMAT; | |
3499 | } | |
25bbbd7a AN |
3500 | obj->efile.secs = calloc(obj->efile.sec_cnt, sizeof(*obj->efile.secs)); |
3501 | if (!obj->efile.secs) | |
3502 | return -ENOMEM; | |
29603665 | 3503 | |
0201c575 AN |
3504 | /* a bunch of ELF parsing functionality depends on processing symbols, |
3505 | * so do the first pass and find the symbol table | |
3506 | */ | |
3507 | scn = NULL; | |
29603665 | 3508 | while ((scn = elf_nextscn(elf, scn)) != NULL) { |
ad23b723 AN |
3509 | sh = elf_sec_hdr(obj, scn); |
3510 | if (!sh) | |
0201c575 AN |
3511 | return -LIBBPF_ERRNO__FORMAT; |
3512 | ||
ad23b723 | 3513 | if (sh->sh_type == SHT_SYMTAB) { |
0201c575 AN |
3514 | if (obj->efile.symbols) { |
3515 | pr_warn("elf: multiple symbol tables in %s\n", obj->path); | |
3516 | return -LIBBPF_ERRNO__FORMAT; | |
3517 | } | |
29603665 | 3518 | |
0201c575 AN |
3519 | data = elf_sec_data(obj, scn); |
3520 | if (!data) | |
3521 | return -LIBBPF_ERRNO__FORMAT; | |
3522 | ||
25bbbd7a AN |
3523 | idx = elf_ndxscn(scn); |
3524 | ||
0201c575 | 3525 | obj->efile.symbols = data; |
25bbbd7a | 3526 | obj->efile.symbols_shndx = idx; |
ad23b723 | 3527 | obj->efile.strtabidx = sh->sh_link; |
0201c575 AN |
3528 | } |
3529 | } | |
3530 | ||
03e601f4 THJ |
3531 | if (!obj->efile.symbols) { |
3532 | pr_warn("elf: couldn't find symbol table in %s, stripped object file?\n", | |
3533 | obj->path); | |
3534 | return -ENOENT; | |
3535 | } | |
3536 | ||
0201c575 AN |
3537 | scn = NULL; |
3538 | while ((scn = elf_nextscn(elf, scn)) != NULL) { | |
25bbbd7a AN |
3539 | idx = elf_ndxscn(scn); |
3540 | sec_desc = &obj->efile.secs[idx]; | |
88a82120 | 3541 | |
ad23b723 AN |
3542 | sh = elf_sec_hdr(obj, scn); |
3543 | if (!sh) | |
01b29d1d | 3544 | return -LIBBPF_ERRNO__FORMAT; |
29603665 | 3545 | |
ad23b723 | 3546 | name = elf_sec_str(obj, sh->sh_name); |
88a82120 | 3547 | if (!name) |
01b29d1d | 3548 | return -LIBBPF_ERRNO__FORMAT; |
29603665 | 3549 | |
ad23b723 | 3550 | if (ignore_elf_section(sh, name)) |
50e09460 AN |
3551 | continue; |
3552 | ||
88a82120 AN |
3553 | data = elf_sec_data(obj, scn); |
3554 | if (!data) | |
01b29d1d | 3555 | return -LIBBPF_ERRNO__FORMAT; |
88a82120 AN |
3556 | |
3557 | pr_debug("elf: section(%d) %s, size %ld, link %d, flags %lx, type=%d\n", | |
077c066a | 3558 | idx, name, (unsigned long)data->d_size, |
ad23b723 AN |
3559 | (int)sh->sh_link, (unsigned long)sh->sh_flags, |
3560 | (int)sh->sh_type); | |
cb1e5e96 | 3561 | |
1713d68b | 3562 | if (strcmp(name, "license") == 0) { |
88a82120 | 3563 | err = bpf_object__init_license(obj, data->d_buf, data->d_size); |
01b29d1d AN |
3564 | if (err) |
3565 | return err; | |
1713d68b | 3566 | } else if (strcmp(name, "version") == 0) { |
88a82120 | 3567 | err = bpf_object__init_kversion(obj, data->d_buf, data->d_size); |
54b8625c JF |
3568 | if (err) |
3569 | return err; | |
1713d68b | 3570 | } else if (strcmp(name, "maps") == 0) { |
e19db676 AN |
3571 | pr_warn("elf: legacy map definitions in 'maps' section are not supported by libbpf v1.0+\n"); |
3572 | return -ENOTSUP; | |
abd29c93 AN |
3573 | } else if (strcmp(name, MAPS_ELF_SEC) == 0) { |
3574 | obj->efile.btf_maps_shndx = idx; | |
1713d68b | 3575 | } else if (strcmp(name, BTF_ELF_SEC) == 0) { |
62554d52 AN |
3576 | if (sh->sh_type != SHT_PROGBITS) |
3577 | return -LIBBPF_ERRNO__FORMAT; | |
1713d68b | 3578 | btf_data = data; |
2993e051 | 3579 | } else if (strcmp(name, BTF_EXT_ELF_SEC) == 0) { |
62554d52 AN |
3580 | if (sh->sh_type != SHT_PROGBITS) |
3581 | return -LIBBPF_ERRNO__FORMAT; | |
f0187f0b | 3582 | btf_ext_data = data; |
ad23b723 | 3583 | } else if (sh->sh_type == SHT_SYMTAB) { |
0201c575 | 3584 | /* already processed during the first pass above */ |
ad23b723 AN |
3585 | } else if (sh->sh_type == SHT_PROGBITS && data->d_size > 0) { |
3586 | if (sh->sh_flags & SHF_EXECINSTR) { | |
f8c7a4d4 JS |
3587 | if (strcmp(name, ".text") == 0) |
3588 | obj->efile.text_shndx = idx; | |
c1122392 | 3589 | err = bpf_object__add_programs(obj, data, name, idx); |
88a82120 | 3590 | if (err) |
01b29d1d | 3591 | return err; |
aed65917 AN |
3592 | } else if (strcmp(name, DATA_SEC) == 0 || |
3593 | str_has_pfx(name, DATA_SEC ".")) { | |
25bbbd7a AN |
3594 | sec_desc->sec_type = SEC_DATA; |
3595 | sec_desc->shdr = sh; | |
3596 | sec_desc->data = data; | |
aed65917 AN |
3597 | } else if (strcmp(name, RODATA_SEC) == 0 || |
3598 | str_has_pfx(name, RODATA_SEC ".")) { | |
25bbbd7a AN |
3599 | sec_desc->sec_type = SEC_RODATA; |
3600 | sec_desc->shdr = sh; | |
3601 | sec_desc->data = data; | |
590a0088 MKL |
3602 | } else if (strcmp(name, STRUCT_OPS_SEC) == 0) { |
3603 | obj->efile.st_ops_data = data; | |
3604 | obj->efile.st_ops_shndx = idx; | |
809a69d6 KFL |
3605 | } else if (strcmp(name, STRUCT_OPS_LINK_SEC) == 0) { |
3606 | obj->efile.st_ops_link_data = data; | |
3607 | obj->efile.st_ops_link_shndx = idx; | |
d859900c | 3608 | } else { |
50e09460 AN |
3609 | pr_info("elf: skipping unrecognized data section(%d) %s\n", |
3610 | idx, name); | |
a5b8bd47 | 3611 | } |
ad23b723 | 3612 | } else if (sh->sh_type == SHT_REL) { |
25bbbd7a | 3613 | int targ_sec_idx = sh->sh_info; /* points to other section */ |
e3d91b0c | 3614 | |
b7332d28 AN |
3615 | if (sh->sh_entsize != sizeof(Elf64_Rel) || |
3616 | targ_sec_idx >= obj->efile.sec_cnt) | |
3617 | return -LIBBPF_ERRNO__FORMAT; | |
3618 | ||
e3d91b0c | 3619 | /* Only do relo for section with exec instructions */ |
25bbbd7a | 3620 | if (!section_have_execinstr(obj, targ_sec_idx) && |
646f02ff | 3621 | strcmp(name, ".rel" STRUCT_OPS_SEC) && |
809a69d6 | 3622 | strcmp(name, ".rel" STRUCT_OPS_LINK_SEC) && |
646f02ff | 3623 | strcmp(name, ".rel" MAPS_ELF_SEC)) { |
50e09460 | 3624 | pr_info("elf: skipping relo section(%d) %s for section(%d) %s\n", |
25bbbd7a AN |
3625 | idx, name, targ_sec_idx, |
3626 | elf_sec_name(obj, elf_sec_by_idx(obj, targ_sec_idx)) ?: "<?>"); | |
e3d91b0c JDB |
3627 | continue; |
3628 | } | |
b62f06e8 | 3629 | |
25bbbd7a AN |
3630 | sec_desc->sec_type = SEC_RELO; |
3631 | sec_desc->shdr = sh; | |
3632 | sec_desc->data = data; | |
dc79f035 AS |
3633 | } else if (sh->sh_type == SHT_NOBITS && (strcmp(name, BSS_SEC) == 0 || |
3634 | str_has_pfx(name, BSS_SEC "."))) { | |
25bbbd7a AN |
3635 | sec_desc->sec_type = SEC_BSS; |
3636 | sec_desc->shdr = sh; | |
3637 | sec_desc->data = data; | |
077c066a | 3638 | } else { |
2e80be60 | 3639 | pr_info("elf: skipping section(%d) %s (size %zu)\n", idx, name, |
ad23b723 | 3640 | (size_t)sh->sh_size); |
bec7d68c | 3641 | } |
29603665 | 3642 | } |
561bbcca | 3643 | |
d3a3aa0c | 3644 | if (!obj->efile.strtabidx || obj->efile.strtabidx > idx) { |
88a82120 | 3645 | pr_warn("elf: symbol strings section missing or invalid in %s\n", obj->path); |
f102154d | 3646 | return -LIBBPF_ERRNO__FORMAT; |
77ba9a5b | 3647 | } |
db2b8b06 AN |
3648 | |
3649 | /* sort BPF programs by section name and in-section instruction offset | |
e3ba8e4e KM |
3650 | * for faster search |
3651 | */ | |
2a6a9bf2 AN |
3652 | if (obj->nr_programs) |
3653 | qsort(obj->programs, obj->nr_programs, sizeof(*obj->programs), cmp_progs); | |
db2b8b06 | 3654 | |
0d13bfce | 3655 | return bpf_object__init_btf(obj, btf_data, btf_ext_data); |
29603665 WN |
3656 | } |
3657 | ||
ad23b723 | 3658 | static bool sym_is_extern(const Elf64_Sym *sym) |
166750bc | 3659 | { |
ad23b723 | 3660 | int bind = ELF64_ST_BIND(sym->st_info); |
166750bc AN |
3661 | /* externs are symbols w/ type=NOTYPE, bind=GLOBAL|WEAK, section=UND */ |
3662 | return sym->st_shndx == SHN_UNDEF && | |
3663 | (bind == STB_GLOBAL || bind == STB_WEAK) && | |
ad23b723 | 3664 | ELF64_ST_TYPE(sym->st_info) == STT_NOTYPE; |
166750bc AN |
3665 | } |
3666 | ||
ad23b723 | 3667 | static bool sym_is_subprog(const Elf64_Sym *sym, int text_shndx) |
53eddb5e | 3668 | { |
ad23b723 AN |
3669 | int bind = ELF64_ST_BIND(sym->st_info); |
3670 | int type = ELF64_ST_TYPE(sym->st_info); | |
53eddb5e YS |
3671 | |
3672 | /* in .text section */ | |
3673 | if (sym->st_shndx != text_shndx) | |
3674 | return false; | |
3675 | ||
3676 | /* local function */ | |
3677 | if (bind == STB_LOCAL && type == STT_SECTION) | |
3678 | return true; | |
3679 | ||
3680 | /* global function */ | |
3681 | return bind == STB_GLOBAL && type == STT_FUNC; | |
3682 | } | |
3683 | ||
166750bc AN |
3684 | static int find_extern_btf_id(const struct btf *btf, const char *ext_name) |
3685 | { | |
3686 | const struct btf_type *t; | |
5bd022ec | 3687 | const char *tname; |
166750bc AN |
3688 | int i, n; |
3689 | ||
3690 | if (!btf) | |
3691 | return -ESRCH; | |
3692 | ||
6a886de0 HC |
3693 | n = btf__type_cnt(btf); |
3694 | for (i = 1; i < n; i++) { | |
166750bc AN |
3695 | t = btf__type_by_id(btf, i); |
3696 | ||
5bd022ec | 3697 | if (!btf_is_var(t) && !btf_is_func(t)) |
166750bc AN |
3698 | continue; |
3699 | ||
5bd022ec MKL |
3700 | tname = btf__name_by_offset(btf, t->name_off); |
3701 | if (strcmp(tname, ext_name)) | |
166750bc AN |
3702 | continue; |
3703 | ||
5bd022ec MKL |
3704 | if (btf_is_var(t) && |
3705 | btf_var(t)->linkage != BTF_VAR_GLOBAL_EXTERN) | |
3706 | return -EINVAL; | |
3707 | ||
3708 | if (btf_is_func(t) && btf_func_linkage(t) != BTF_FUNC_EXTERN) | |
166750bc AN |
3709 | return -EINVAL; |
3710 | ||
3711 | return i; | |
3712 | } | |
3713 | ||
3714 | return -ENOENT; | |
3715 | } | |
3716 | ||
2e33efe3 AN |
3717 | static int find_extern_sec_btf_id(struct btf *btf, int ext_btf_id) { |
3718 | const struct btf_var_secinfo *vs; | |
3719 | const struct btf_type *t; | |
3720 | int i, j, n; | |
3721 | ||
3722 | if (!btf) | |
3723 | return -ESRCH; | |
3724 | ||
6a886de0 HC |
3725 | n = btf__type_cnt(btf); |
3726 | for (i = 1; i < n; i++) { | |
2e33efe3 AN |
3727 | t = btf__type_by_id(btf, i); |
3728 | ||
3729 | if (!btf_is_datasec(t)) | |
3730 | continue; | |
3731 | ||
3732 | vs = btf_var_secinfos(t); | |
3733 | for (j = 0; j < btf_vlen(t); j++, vs++) { | |
3734 | if (vs->type == ext_btf_id) | |
3735 | return i; | |
3736 | } | |
3737 | } | |
3738 | ||
3739 | return -ENOENT; | |
3740 | } | |
3741 | ||
3742 | static enum kcfg_type find_kcfg_type(const struct btf *btf, int id, | |
3743 | bool *is_signed) | |
166750bc AN |
3744 | { |
3745 | const struct btf_type *t; | |
3746 | const char *name; | |
3747 | ||
3748 | t = skip_mods_and_typedefs(btf, id, NULL); | |
3749 | name = btf__name_by_offset(btf, t->name_off); | |
3750 | ||
3751 | if (is_signed) | |
3752 | *is_signed = false; | |
3753 | switch (btf_kind(t)) { | |
3754 | case BTF_KIND_INT: { | |
3755 | int enc = btf_int_encoding(t); | |
3756 | ||
3757 | if (enc & BTF_INT_BOOL) | |
2e33efe3 | 3758 | return t->size == 1 ? KCFG_BOOL : KCFG_UNKNOWN; |
166750bc AN |
3759 | if (is_signed) |
3760 | *is_signed = enc & BTF_INT_SIGNED; | |
3761 | if (t->size == 1) | |
2e33efe3 | 3762 | return KCFG_CHAR; |
166750bc | 3763 | if (t->size < 1 || t->size > 8 || (t->size & (t->size - 1))) |
2e33efe3 AN |
3764 | return KCFG_UNKNOWN; |
3765 | return KCFG_INT; | |
166750bc AN |
3766 | } |
3767 | case BTF_KIND_ENUM: | |
3768 | if (t->size != 4) | |
2e33efe3 | 3769 | return KCFG_UNKNOWN; |
166750bc | 3770 | if (strcmp(name, "libbpf_tristate")) |
2e33efe3 AN |
3771 | return KCFG_UNKNOWN; |
3772 | return KCFG_TRISTATE; | |
f2a62588 YS |
3773 | case BTF_KIND_ENUM64: |
3774 | if (strcmp(name, "libbpf_tristate")) | |
3775 | return KCFG_UNKNOWN; | |
3776 | return KCFG_TRISTATE; | |
166750bc AN |
3777 | case BTF_KIND_ARRAY: |
3778 | if (btf_array(t)->nelems == 0) | |
2e33efe3 AN |
3779 | return KCFG_UNKNOWN; |
3780 | if (find_kcfg_type(btf, btf_array(t)->type, NULL) != KCFG_CHAR) | |
3781 | return KCFG_UNKNOWN; | |
3782 | return KCFG_CHAR_ARR; | |
166750bc | 3783 | default: |
2e33efe3 | 3784 | return KCFG_UNKNOWN; |
166750bc AN |
3785 | } |
3786 | } | |
3787 | ||
3788 | static int cmp_externs(const void *_a, const void *_b) | |
3789 | { | |
3790 | const struct extern_desc *a = _a; | |
3791 | const struct extern_desc *b = _b; | |
3792 | ||
2e33efe3 AN |
3793 | if (a->type != b->type) |
3794 | return a->type < b->type ? -1 : 1; | |
3795 | ||
3796 | if (a->type == EXT_KCFG) { | |
3797 | /* descending order by alignment requirements */ | |
3798 | if (a->kcfg.align != b->kcfg.align) | |
3799 | return a->kcfg.align > b->kcfg.align ? -1 : 1; | |
3800 | /* ascending order by size, within same alignment class */ | |
3801 | if (a->kcfg.sz != b->kcfg.sz) | |
3802 | return a->kcfg.sz < b->kcfg.sz ? -1 : 1; | |
3803 | } | |
3804 | ||
166750bc AN |
3805 | /* resolve ties by name */ |
3806 | return strcmp(a->name, b->name); | |
3807 | } | |
3808 | ||
1c0c7074 AN |
3809 | static int find_int_btf_id(const struct btf *btf) |
3810 | { | |
3811 | const struct btf_type *t; | |
3812 | int i, n; | |
3813 | ||
6a886de0 HC |
3814 | n = btf__type_cnt(btf); |
3815 | for (i = 1; i < n; i++) { | |
1c0c7074 AN |
3816 | t = btf__type_by_id(btf, i); |
3817 | ||
3818 | if (btf_is_int(t) && btf_int_bits(t) == 32) | |
3819 | return i; | |
3820 | } | |
3821 | ||
3822 | return 0; | |
3823 | } | |
3824 | ||
5bd022ec MKL |
3825 | static int add_dummy_ksym_var(struct btf *btf) |
3826 | { | |
3827 | int i, int_btf_id, sec_btf_id, dummy_var_btf_id; | |
3828 | const struct btf_var_secinfo *vs; | |
3829 | const struct btf_type *sec; | |
3830 | ||
9683e577 IR |
3831 | if (!btf) |
3832 | return 0; | |
3833 | ||
5bd022ec MKL |
3834 | sec_btf_id = btf__find_by_name_kind(btf, KSYMS_SEC, |
3835 | BTF_KIND_DATASEC); | |
3836 | if (sec_btf_id < 0) | |
3837 | return 0; | |
3838 | ||
3839 | sec = btf__type_by_id(btf, sec_btf_id); | |
3840 | vs = btf_var_secinfos(sec); | |
3841 | for (i = 0; i < btf_vlen(sec); i++, vs++) { | |
3842 | const struct btf_type *vt; | |
3843 | ||
3844 | vt = btf__type_by_id(btf, vs->type); | |
3845 | if (btf_is_func(vt)) | |
3846 | break; | |
3847 | } | |
3848 | ||
3849 | /* No func in ksyms sec. No need to add dummy var. */ | |
3850 | if (i == btf_vlen(sec)) | |
3851 | return 0; | |
3852 | ||
3853 | int_btf_id = find_int_btf_id(btf); | |
3854 | dummy_var_btf_id = btf__add_var(btf, | |
3855 | "dummy_ksym", | |
3856 | BTF_VAR_GLOBAL_ALLOCATED, | |
3857 | int_btf_id); | |
3858 | if (dummy_var_btf_id < 0) | |
3859 | pr_warn("cannot create a dummy_ksym var\n"); | |
3860 | ||
3861 | return dummy_var_btf_id; | |
3862 | } | |
3863 | ||
166750bc AN |
3864 | static int bpf_object__collect_externs(struct bpf_object *obj) |
3865 | { | |
1c0c7074 | 3866 | struct btf_type *sec, *kcfg_sec = NULL, *ksym_sec = NULL; |
166750bc AN |
3867 | const struct btf_type *t; |
3868 | struct extern_desc *ext; | |
5bd022ec | 3869 | int i, n, off, dummy_var_btf_id; |
2e33efe3 | 3870 | const char *ext_name, *sec_name; |
5964a223 | 3871 | size_t ext_essent_len; |
166750bc | 3872 | Elf_Scn *scn; |
ad23b723 | 3873 | Elf64_Shdr *sh; |
166750bc AN |
3874 | |
3875 | if (!obj->efile.symbols) | |
3876 | return 0; | |
3877 | ||
88a82120 | 3878 | scn = elf_sec_by_idx(obj, obj->efile.symbols_shndx); |
ad23b723 | 3879 | sh = elf_sec_hdr(obj, scn); |
83390787 | 3880 | if (!sh || sh->sh_entsize != sizeof(Elf64_Sym)) |
166750bc | 3881 | return -LIBBPF_ERRNO__FORMAT; |
166750bc | 3882 | |
5bd022ec MKL |
3883 | dummy_var_btf_id = add_dummy_ksym_var(obj->btf); |
3884 | if (dummy_var_btf_id < 0) | |
3885 | return dummy_var_btf_id; | |
3886 | ||
ad23b723 | 3887 | n = sh->sh_size / sh->sh_entsize; |
166750bc | 3888 | pr_debug("looking for externs among %d symbols...\n", n); |
88a82120 | 3889 | |
166750bc | 3890 | for (i = 0; i < n; i++) { |
ad23b723 | 3891 | Elf64_Sym *sym = elf_sym_by_idx(obj, i); |
166750bc | 3892 | |
ad23b723 | 3893 | if (!sym) |
166750bc | 3894 | return -LIBBPF_ERRNO__FORMAT; |
ad23b723 | 3895 | if (!sym_is_extern(sym)) |
166750bc | 3896 | continue; |
ad23b723 | 3897 | ext_name = elf_sym_str(obj, sym->st_name); |
166750bc AN |
3898 | if (!ext_name || !ext_name[0]) |
3899 | continue; | |
3900 | ||
3901 | ext = obj->externs; | |
029258d7 | 3902 | ext = libbpf_reallocarray(ext, obj->nr_extern + 1, sizeof(*ext)); |
166750bc AN |
3903 | if (!ext) |
3904 | return -ENOMEM; | |
3905 | obj->externs = ext; | |
3906 | ext = &ext[obj->nr_extern]; | |
3907 | memset(ext, 0, sizeof(*ext)); | |
3908 | obj->nr_extern++; | |
3909 | ||
3910 | ext->btf_id = find_extern_btf_id(obj->btf, ext_name); | |
3911 | if (ext->btf_id <= 0) { | |
3912 | pr_warn("failed to find BTF for extern '%s': %d\n", | |
3913 | ext_name, ext->btf_id); | |
3914 | return ext->btf_id; | |
3915 | } | |
3916 | t = btf__type_by_id(obj->btf, ext->btf_id); | |
3917 | ext->name = btf__name_by_offset(obj->btf, t->name_off); | |
3918 | ext->sym_idx = i; | |
ad23b723 | 3919 | ext->is_weak = ELF64_ST_BIND(sym->st_info) == STB_WEAK; |
2e33efe3 | 3920 | |
5964a223 DM |
3921 | ext_essent_len = bpf_core_essential_name_len(ext->name); |
3922 | ext->essent_name = NULL; | |
3923 | if (ext_essent_len != strlen(ext->name)) { | |
3924 | ext->essent_name = strndup(ext->name, ext_essent_len); | |
3925 | if (!ext->essent_name) | |
3926 | return -ENOMEM; | |
3927 | } | |
3928 | ||
2e33efe3 AN |
3929 | ext->sec_btf_id = find_extern_sec_btf_id(obj->btf, ext->btf_id); |
3930 | if (ext->sec_btf_id <= 0) { | |
3931 | pr_warn("failed to find BTF for extern '%s' [%d] section: %d\n", | |
3932 | ext_name, ext->btf_id, ext->sec_btf_id); | |
3933 | return ext->sec_btf_id; | |
166750bc | 3934 | } |
2e33efe3 AN |
3935 | sec = (void *)btf__type_by_id(obj->btf, ext->sec_btf_id); |
3936 | sec_name = btf__name_by_offset(obj->btf, sec->name_off); | |
3937 | ||
3938 | if (strcmp(sec_name, KCONFIG_SEC) == 0) { | |
5bd022ec MKL |
3939 | if (btf_is_func(t)) { |
3940 | pr_warn("extern function %s is unsupported under %s section\n", | |
3941 | ext->name, KCONFIG_SEC); | |
3942 | return -ENOTSUP; | |
3943 | } | |
2e33efe3 AN |
3944 | kcfg_sec = sec; |
3945 | ext->type = EXT_KCFG; | |
3946 | ext->kcfg.sz = btf__resolve_size(obj->btf, t->type); | |
3947 | if (ext->kcfg.sz <= 0) { | |
3948 | pr_warn("failed to resolve size of extern (kcfg) '%s': %d\n", | |
3949 | ext_name, ext->kcfg.sz); | |
3950 | return ext->kcfg.sz; | |
3951 | } | |
3952 | ext->kcfg.align = btf__align_of(obj->btf, t->type); | |
3953 | if (ext->kcfg.align <= 0) { | |
3954 | pr_warn("failed to determine alignment of extern (kcfg) '%s': %d\n", | |
3955 | ext_name, ext->kcfg.align); | |
3956 | return -EINVAL; | |
3957 | } | |
3958 | ext->kcfg.type = find_kcfg_type(obj->btf, t->type, | |
e3ba8e4e | 3959 | &ext->kcfg.is_signed); |
2e33efe3 | 3960 | if (ext->kcfg.type == KCFG_UNKNOWN) { |
55d00c37 | 3961 | pr_warn("extern (kcfg) '%s': type is unsupported\n", ext_name); |
2e33efe3 AN |
3962 | return -ENOTSUP; |
3963 | } | |
1c0c7074 | 3964 | } else if (strcmp(sec_name, KSYMS_SEC) == 0) { |
1c0c7074 AN |
3965 | ksym_sec = sec; |
3966 | ext->type = EXT_KSYM; | |
d370bbe1 HL |
3967 | skip_mods_and_typedefs(obj->btf, t->type, |
3968 | &ext->ksym.type_id); | |
2e33efe3 AN |
3969 | } else { |
3970 | pr_warn("unrecognized extern section '%s'\n", sec_name); | |
166750bc AN |
3971 | return -ENOTSUP; |
3972 | } | |
3973 | } | |
3974 | pr_debug("collected %d externs total\n", obj->nr_extern); | |
3975 | ||
3976 | if (!obj->nr_extern) | |
3977 | return 0; | |
3978 | ||
2e33efe3 | 3979 | /* sort externs by type, for kcfg ones also by (align, size, name) */ |
166750bc | 3980 | qsort(obj->externs, obj->nr_extern, sizeof(*ext), cmp_externs); |
166750bc | 3981 | |
1c0c7074 AN |
3982 | /* for .ksyms section, we need to turn all externs into allocated |
3983 | * variables in BTF to pass kernel verification; we do this by | |
3984 | * pretending that each extern is a 8-byte variable | |
3985 | */ | |
3986 | if (ksym_sec) { | |
3987 | /* find existing 4-byte integer type in BTF to use for fake | |
3988 | * extern variables in DATASEC | |
3989 | */ | |
3990 | int int_btf_id = find_int_btf_id(obj->btf); | |
5bd022ec MKL |
3991 | /* For extern function, a dummy_var added earlier |
3992 | * will be used to replace the vs->type and | |
3993 | * its name string will be used to refill | |
3994 | * the missing param's name. | |
3995 | */ | |
3996 | const struct btf_type *dummy_var; | |
1c0c7074 | 3997 | |
5bd022ec | 3998 | dummy_var = btf__type_by_id(obj->btf, dummy_var_btf_id); |
1c0c7074 AN |
3999 | for (i = 0; i < obj->nr_extern; i++) { |
4000 | ext = &obj->externs[i]; | |
4001 | if (ext->type != EXT_KSYM) | |
4002 | continue; | |
4003 | pr_debug("extern (ksym) #%d: symbol %d, name %s\n", | |
4004 | i, ext->sym_idx, ext->name); | |
4005 | } | |
4006 | ||
4007 | sec = ksym_sec; | |
4008 | n = btf_vlen(sec); | |
4009 | for (i = 0, off = 0; i < n; i++, off += sizeof(int)) { | |
4010 | struct btf_var_secinfo *vs = btf_var_secinfos(sec) + i; | |
4011 | struct btf_type *vt; | |
4012 | ||
4013 | vt = (void *)btf__type_by_id(obj->btf, vs->type); | |
4014 | ext_name = btf__name_by_offset(obj->btf, vt->name_off); | |
4015 | ext = find_extern_by_name(obj, ext_name); | |
4016 | if (!ext) { | |
5bd022ec MKL |
4017 | pr_warn("failed to find extern definition for BTF %s '%s'\n", |
4018 | btf_kind_str(vt), ext_name); | |
1c0c7074 AN |
4019 | return -ESRCH; |
4020 | } | |
5bd022ec MKL |
4021 | if (btf_is_func(vt)) { |
4022 | const struct btf_type *func_proto; | |
4023 | struct btf_param *param; | |
4024 | int j; | |
4025 | ||
4026 | func_proto = btf__type_by_id(obj->btf, | |
4027 | vt->type); | |
4028 | param = btf_params(func_proto); | |
4029 | /* Reuse the dummy_var string if the | |
4030 | * func proto does not have param name. | |
4031 | */ | |
4032 | for (j = 0; j < btf_vlen(func_proto); j++) | |
4033 | if (param[j].type && !param[j].name_off) | |
4034 | param[j].name_off = | |
4035 | dummy_var->name_off; | |
4036 | vs->type = dummy_var_btf_id; | |
4037 | vt->info &= ~0xffff; | |
4038 | vt->info |= BTF_FUNC_GLOBAL; | |
4039 | } else { | |
4040 | btf_var(vt)->linkage = BTF_VAR_GLOBAL_ALLOCATED; | |
4041 | vt->type = int_btf_id; | |
4042 | } | |
1c0c7074 AN |
4043 | vs->offset = off; |
4044 | vs->size = sizeof(int); | |
4045 | } | |
4046 | sec->size = off; | |
4047 | } | |
4048 | ||
2e33efe3 AN |
4049 | if (kcfg_sec) { |
4050 | sec = kcfg_sec; | |
4051 | /* for kcfg externs calculate their offsets within a .kconfig map */ | |
4052 | off = 0; | |
4053 | for (i = 0; i < obj->nr_extern; i++) { | |
4054 | ext = &obj->externs[i]; | |
4055 | if (ext->type != EXT_KCFG) | |
4056 | continue; | |
166750bc | 4057 | |
2e33efe3 AN |
4058 | ext->kcfg.data_off = roundup(off, ext->kcfg.align); |
4059 | off = ext->kcfg.data_off + ext->kcfg.sz; | |
1c0c7074 | 4060 | pr_debug("extern (kcfg) #%d: symbol %d, off %u, name %s\n", |
2e33efe3 AN |
4061 | i, ext->sym_idx, ext->kcfg.data_off, ext->name); |
4062 | } | |
4063 | sec->size = off; | |
4064 | n = btf_vlen(sec); | |
4065 | for (i = 0; i < n; i++) { | |
4066 | struct btf_var_secinfo *vs = btf_var_secinfos(sec) + i; | |
4067 | ||
4068 | t = btf__type_by_id(obj->btf, vs->type); | |
4069 | ext_name = btf__name_by_offset(obj->btf, t->name_off); | |
4070 | ext = find_extern_by_name(obj, ext_name); | |
4071 | if (!ext) { | |
4072 | pr_warn("failed to find extern definition for BTF var '%s'\n", | |
4073 | ext_name); | |
4074 | return -ESRCH; | |
4075 | } | |
4076 | btf_var(t)->linkage = BTF_VAR_GLOBAL_ALLOCATED; | |
4077 | vs->offset = ext->kcfg.data_off; | |
166750bc | 4078 | } |
166750bc | 4079 | } |
166750bc AN |
4080 | return 0; |
4081 | } | |
4082 | ||
bd054102 AN |
4083 | static bool prog_is_subprog(const struct bpf_object *obj, const struct bpf_program *prog) |
4084 | { | |
197afc63 | 4085 | return prog->sec_idx == obj->efile.text_shndx && obj->nr_programs > 1; |
c3c55696 AN |
4086 | } |
4087 | ||
01af3bf0 AN |
4088 | struct bpf_program * |
4089 | bpf_object__find_program_by_name(const struct bpf_object *obj, | |
4090 | const char *name) | |
4091 | { | |
4092 | struct bpf_program *prog; | |
4093 | ||
4094 | bpf_object__for_each_program(prog, obj) { | |
c3c55696 AN |
4095 | if (prog_is_subprog(obj, prog)) |
4096 | continue; | |
01af3bf0 AN |
4097 | if (!strcmp(prog->name, name)) |
4098 | return prog; | |
4099 | } | |
e9fc3ce9 | 4100 | return errno = ENOENT, NULL; |
01af3bf0 AN |
4101 | } |
4102 | ||
d859900c DB |
4103 | static bool bpf_object__shndx_is_data(const struct bpf_object *obj, |
4104 | int shndx) | |
4105 | { | |
25bbbd7a AN |
4106 | switch (obj->efile.secs[shndx].sec_type) { |
4107 | case SEC_BSS: | |
4108 | case SEC_DATA: | |
4109 | case SEC_RODATA: | |
4110 | return true; | |
4111 | default: | |
4112 | return false; | |
4113 | } | |
d859900c DB |
4114 | } |
4115 | ||
4116 | static bool bpf_object__shndx_is_maps(const struct bpf_object *obj, | |
4117 | int shndx) | |
4118 | { | |
e19db676 | 4119 | return shndx == obj->efile.btf_maps_shndx; |
d859900c DB |
4120 | } |
4121 | ||
d859900c DB |
4122 | static enum libbpf_map_type |
4123 | bpf_object__section_to_libbpf_map_type(const struct bpf_object *obj, int shndx) | |
4124 | { | |
25bbbd7a AN |
4125 | if (shndx == obj->efile.symbols_shndx) |
4126 | return LIBBPF_MAP_KCONFIG; | |
4127 | ||
4128 | switch (obj->efile.secs[shndx].sec_type) { | |
4129 | case SEC_BSS: | |
d859900c | 4130 | return LIBBPF_MAP_BSS; |
25bbbd7a AN |
4131 | case SEC_DATA: |
4132 | return LIBBPF_MAP_DATA; | |
4133 | case SEC_RODATA: | |
d859900c | 4134 | return LIBBPF_MAP_RODATA; |
25bbbd7a | 4135 | default: |
d859900c | 4136 | return LIBBPF_MAP_UNSPEC; |
25bbbd7a | 4137 | } |
d859900c DB |
4138 | } |
4139 | ||
1f8e2bcb AN |
4140 | static int bpf_program__record_reloc(struct bpf_program *prog, |
4141 | struct reloc_desc *reloc_desc, | |
9c0f8cbd | 4142 | __u32 insn_idx, const char *sym_name, |
ad23b723 | 4143 | const Elf64_Sym *sym, const Elf64_Rel *rel) |
1f8e2bcb AN |
4144 | { |
4145 | struct bpf_insn *insn = &prog->insns[insn_idx]; | |
4146 | size_t map_idx, nr_maps = prog->obj->nr_maps; | |
4147 | struct bpf_object *obj = prog->obj; | |
4148 | __u32 shdr_idx = sym->st_shndx; | |
4149 | enum libbpf_map_type type; | |
9c0f8cbd | 4150 | const char *sym_sec_name; |
1f8e2bcb AN |
4151 | struct bpf_map *map; |
4152 | ||
aa0b8d43 | 4153 | if (!is_call_insn(insn) && !is_ldimm64_insn(insn)) { |
9c0f8cbd AN |
4154 | pr_warn("prog '%s': invalid relo against '%s' for insns[%d].code 0x%x\n", |
4155 | prog->name, sym_name, insn_idx, insn->code); | |
1f8e2bcb AN |
4156 | return -LIBBPF_ERRNO__RELOC; |
4157 | } | |
166750bc AN |
4158 | |
4159 | if (sym_is_extern(sym)) { | |
ad23b723 | 4160 | int sym_idx = ELF64_R_SYM(rel->r_info); |
166750bc AN |
4161 | int i, n = obj->nr_extern; |
4162 | struct extern_desc *ext; | |
4163 | ||
4164 | for (i = 0; i < n; i++) { | |
4165 | ext = &obj->externs[i]; | |
4166 | if (ext->sym_idx == sym_idx) | |
4167 | break; | |
4168 | } | |
4169 | if (i >= n) { | |
9c0f8cbd AN |
4170 | pr_warn("prog '%s': extern relo failed to find extern for '%s' (%d)\n", |
4171 | prog->name, sym_name, sym_idx); | |
166750bc AN |
4172 | return -LIBBPF_ERRNO__RELOC; |
4173 | } | |
9c0f8cbd AN |
4174 | pr_debug("prog '%s': found extern #%d '%s' (sym %d) for insn #%u\n", |
4175 | prog->name, i, ext->name, ext->sym_idx, insn_idx); | |
5bd022ec | 4176 | if (insn->code == (BPF_JMP | BPF_CALL)) |
a18f7214 | 4177 | reloc_desc->type = RELO_EXTERN_CALL; |
5bd022ec | 4178 | else |
a18f7214 | 4179 | reloc_desc->type = RELO_EXTERN_LD64; |
166750bc | 4180 | reloc_desc->insn_idx = insn_idx; |
3055ddd6 | 4181 | reloc_desc->ext_idx = i; |
166750bc AN |
4182 | return 0; |
4183 | } | |
4184 | ||
aa0b8d43 MKL |
4185 | /* sub-program call relocation */ |
4186 | if (is_call_insn(insn)) { | |
4187 | if (insn->src_reg != BPF_PSEUDO_CALL) { | |
4188 | pr_warn("prog '%s': incorrect bpf_call opcode\n", prog->name); | |
4189 | return -LIBBPF_ERRNO__RELOC; | |
4190 | } | |
4191 | /* text_shndx can be 0, if no default "main" program exists */ | |
4192 | if (!shdr_idx || shdr_idx != obj->efile.text_shndx) { | |
4193 | sym_sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, shdr_idx)); | |
4194 | pr_warn("prog '%s': bad call relo against '%s' in section '%s'\n", | |
4195 | prog->name, sym_name, sym_sec_name); | |
4196 | return -LIBBPF_ERRNO__RELOC; | |
4197 | } | |
4198 | if (sym->st_value % BPF_INSN_SZ) { | |
4199 | pr_warn("prog '%s': bad call relo against '%s' at offset %zu\n", | |
4200 | prog->name, sym_name, (size_t)sym->st_value); | |
4201 | return -LIBBPF_ERRNO__RELOC; | |
4202 | } | |
4203 | reloc_desc->type = RELO_CALL; | |
4204 | reloc_desc->insn_idx = insn_idx; | |
4205 | reloc_desc->sym_off = sym->st_value; | |
4206 | return 0; | |
4207 | } | |
4208 | ||
1f8e2bcb | 4209 | if (!shdr_idx || shdr_idx >= SHN_LORESERVE) { |
9c0f8cbd AN |
4210 | pr_warn("prog '%s': invalid relo against '%s' in special section 0x%x; forgot to initialize global var?..\n", |
4211 | prog->name, sym_name, shdr_idx); | |
1f8e2bcb AN |
4212 | return -LIBBPF_ERRNO__RELOC; |
4213 | } | |
4214 | ||
53eddb5e YS |
4215 | /* loading subprog addresses */ |
4216 | if (sym_is_subprog(sym, obj->efile.text_shndx)) { | |
4217 | /* global_func: sym->st_value = offset in the section, insn->imm = 0. | |
4218 | * local_func: sym->st_value = 0, insn->imm = offset in the section. | |
4219 | */ | |
4220 | if ((sym->st_value % BPF_INSN_SZ) || (insn->imm % BPF_INSN_SZ)) { | |
4221 | pr_warn("prog '%s': bad subprog addr relo against '%s' at offset %zu+%d\n", | |
4222 | prog->name, sym_name, (size_t)sym->st_value, insn->imm); | |
4223 | return -LIBBPF_ERRNO__RELOC; | |
4224 | } | |
4225 | ||
4226 | reloc_desc->type = RELO_SUBPROG_ADDR; | |
4227 | reloc_desc->insn_idx = insn_idx; | |
4228 | reloc_desc->sym_off = sym->st_value; | |
4229 | return 0; | |
4230 | } | |
4231 | ||
1f8e2bcb | 4232 | type = bpf_object__section_to_libbpf_map_type(obj, shdr_idx); |
9c0f8cbd | 4233 | sym_sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, shdr_idx)); |
1f8e2bcb AN |
4234 | |
4235 | /* generic map reference relocation */ | |
4236 | if (type == LIBBPF_MAP_UNSPEC) { | |
4237 | if (!bpf_object__shndx_is_maps(obj, shdr_idx)) { | |
9c0f8cbd AN |
4238 | pr_warn("prog '%s': bad map relo against '%s' in section '%s'\n", |
4239 | prog->name, sym_name, sym_sec_name); | |
1f8e2bcb AN |
4240 | return -LIBBPF_ERRNO__RELOC; |
4241 | } | |
4242 | for (map_idx = 0; map_idx < nr_maps; map_idx++) { | |
4243 | map = &obj->maps[map_idx]; | |
4244 | if (map->libbpf_type != type || | |
4245 | map->sec_idx != sym->st_shndx || | |
4246 | map->sec_offset != sym->st_value) | |
4247 | continue; | |
9c0f8cbd AN |
4248 | pr_debug("prog '%s': found map %zd (%s, sec %d, off %zu) for insn #%u\n", |
4249 | prog->name, map_idx, map->name, map->sec_idx, | |
1f8e2bcb AN |
4250 | map->sec_offset, insn_idx); |
4251 | break; | |
4252 | } | |
4253 | if (map_idx >= nr_maps) { | |
9c0f8cbd AN |
4254 | pr_warn("prog '%s': map relo failed to find map for section '%s', off %zu\n", |
4255 | prog->name, sym_sec_name, (size_t)sym->st_value); | |
1f8e2bcb AN |
4256 | return -LIBBPF_ERRNO__RELOC; |
4257 | } | |
4258 | reloc_desc->type = RELO_LD64; | |
4259 | reloc_desc->insn_idx = insn_idx; | |
4260 | reloc_desc->map_idx = map_idx; | |
53f8dd43 | 4261 | reloc_desc->sym_off = 0; /* sym->st_value determines map_idx */ |
1f8e2bcb AN |
4262 | return 0; |
4263 | } | |
4264 | ||
4265 | /* global data map relocation */ | |
4266 | if (!bpf_object__shndx_is_data(obj, shdr_idx)) { | |
9c0f8cbd AN |
4267 | pr_warn("prog '%s': bad data relo against section '%s'\n", |
4268 | prog->name, sym_sec_name); | |
1f8e2bcb | 4269 | return -LIBBPF_ERRNO__RELOC; |
1f8e2bcb | 4270 | } |
1f8e2bcb AN |
4271 | for (map_idx = 0; map_idx < nr_maps; map_idx++) { |
4272 | map = &obj->maps[map_idx]; | |
25bbbd7a | 4273 | if (map->libbpf_type != type || map->sec_idx != sym->st_shndx) |
1f8e2bcb | 4274 | continue; |
9c0f8cbd AN |
4275 | pr_debug("prog '%s': found data map %zd (%s, sec %d, off %zu) for insn %u\n", |
4276 | prog->name, map_idx, map->name, map->sec_idx, | |
4277 | map->sec_offset, insn_idx); | |
1f8e2bcb AN |
4278 | break; |
4279 | } | |
4280 | if (map_idx >= nr_maps) { | |
9c0f8cbd AN |
4281 | pr_warn("prog '%s': data relo failed to find map for section '%s'\n", |
4282 | prog->name, sym_sec_name); | |
1f8e2bcb AN |
4283 | return -LIBBPF_ERRNO__RELOC; |
4284 | } | |
4285 | ||
4286 | reloc_desc->type = RELO_DATA; | |
4287 | reloc_desc->insn_idx = insn_idx; | |
4288 | reloc_desc->map_idx = map_idx; | |
53f8dd43 | 4289 | reloc_desc->sym_off = sym->st_value; |
1f8e2bcb AN |
4290 | return 0; |
4291 | } | |
4292 | ||
db2b8b06 AN |
4293 | static bool prog_contains_insn(const struct bpf_program *prog, size_t insn_idx) |
4294 | { | |
4295 | return insn_idx >= prog->sec_insn_off && | |
4296 | insn_idx < prog->sec_insn_off + prog->sec_insn_cnt; | |
4297 | } | |
4298 | ||
4299 | static struct bpf_program *find_prog_by_sec_insn(const struct bpf_object *obj, | |
4300 | size_t sec_idx, size_t insn_idx) | |
4301 | { | |
4302 | int l = 0, r = obj->nr_programs - 1, m; | |
4303 | struct bpf_program *prog; | |
4304 | ||
d0d382f9 SHY |
4305 | if (!obj->nr_programs) |
4306 | return NULL; | |
4307 | ||
db2b8b06 AN |
4308 | while (l < r) { |
4309 | m = l + (r - l + 1) / 2; | |
4310 | prog = &obj->programs[m]; | |
4311 | ||
4312 | if (prog->sec_idx < sec_idx || | |
4313 | (prog->sec_idx == sec_idx && prog->sec_insn_off <= insn_idx)) | |
4314 | l = m; | |
4315 | else | |
4316 | r = m - 1; | |
4317 | } | |
4318 | /* matching program could be at index l, but it still might be the | |
4319 | * wrong one, so we need to double check conditions for the last time | |
4320 | */ | |
4321 | prog = &obj->programs[l]; | |
4322 | if (prog->sec_idx == sec_idx && prog_contains_insn(prog, insn_idx)) | |
4323 | return prog; | |
4324 | return NULL; | |
4325 | } | |
4326 | ||
34090915 | 4327 | static int |
ad23b723 | 4328 | bpf_object__collect_prog_relos(struct bpf_object *obj, Elf64_Shdr *shdr, Elf_Data *data) |
34090915 | 4329 | { |
9c0f8cbd | 4330 | const char *relo_sec_name, *sec_name; |
b7332d28 | 4331 | size_t sec_idx = shdr->sh_info, sym_idx; |
c3c55696 AN |
4332 | struct bpf_program *prog; |
4333 | struct reloc_desc *relos; | |
1f8e2bcb | 4334 | int err, i, nrels; |
c3c55696 AN |
4335 | const char *sym_name; |
4336 | __u32 insn_idx; | |
6245947c AN |
4337 | Elf_Scn *scn; |
4338 | Elf_Data *scn_data; | |
ad23b723 AN |
4339 | Elf64_Sym *sym; |
4340 | Elf64_Rel *rel; | |
34090915 | 4341 | |
b7332d28 AN |
4342 | if (sec_idx >= obj->efile.sec_cnt) |
4343 | return -EINVAL; | |
4344 | ||
6245947c AN |
4345 | scn = elf_sec_by_idx(obj, sec_idx); |
4346 | scn_data = elf_sec_data(obj, scn); | |
4347 | ||
9c0f8cbd | 4348 | relo_sec_name = elf_sec_str(obj, shdr->sh_name); |
6245947c | 4349 | sec_name = elf_sec_name(obj, scn); |
9c0f8cbd AN |
4350 | if (!relo_sec_name || !sec_name) |
4351 | return -EINVAL; | |
4352 | ||
4353 | pr_debug("sec '%s': collecting relocation for section(%zu) '%s'\n", | |
4354 | relo_sec_name, sec_idx, sec_name); | |
34090915 WN |
4355 | nrels = shdr->sh_size / shdr->sh_entsize; |
4356 | ||
34090915 | 4357 | for (i = 0; i < nrels; i++) { |
ad23b723 AN |
4358 | rel = elf_rel_by_idx(data, i); |
4359 | if (!rel) { | |
9c0f8cbd | 4360 | pr_warn("sec '%s': failed to get relo #%d\n", relo_sec_name, i); |
6371ca3b | 4361 | return -LIBBPF_ERRNO__FORMAT; |
34090915 | 4362 | } |
ad23b723 | 4363 | |
b7332d28 AN |
4364 | sym_idx = ELF64_R_SYM(rel->r_info); |
4365 | sym = elf_sym_by_idx(obj, sym_idx); | |
ad23b723 | 4366 | if (!sym) { |
b7332d28 AN |
4367 | pr_warn("sec '%s': symbol #%zu not found for relo #%d\n", |
4368 | relo_sec_name, sym_idx, i); | |
4369 | return -LIBBPF_ERRNO__FORMAT; | |
4370 | } | |
4371 | ||
4372 | if (sym->st_shndx >= obj->efile.sec_cnt) { | |
4373 | pr_warn("sec '%s': corrupted symbol #%zu pointing to invalid section #%zu for relo #%d\n", | |
4374 | relo_sec_name, sym_idx, (size_t)sym->st_shndx, i); | |
6371ca3b | 4375 | return -LIBBPF_ERRNO__FORMAT; |
34090915 | 4376 | } |
6245947c | 4377 | |
ad23b723 | 4378 | if (rel->r_offset % BPF_INSN_SZ || rel->r_offset >= scn_data->d_size) { |
9c0f8cbd | 4379 | pr_warn("sec '%s': invalid offset 0x%zx for relo #%d\n", |
b7332d28 | 4380 | relo_sec_name, (size_t)rel->r_offset, i); |
1f8e2bcb | 4381 | return -LIBBPF_ERRNO__FORMAT; |
9c0f8cbd | 4382 | } |
d859900c | 4383 | |
ad23b723 | 4384 | insn_idx = rel->r_offset / BPF_INSN_SZ; |
c3c55696 AN |
4385 | /* relocations against static functions are recorded as |
4386 | * relocations against the section that contains a function; | |
4387 | * in such case, symbol will be STT_SECTION and sym.st_name | |
4388 | * will point to empty string (0), so fetch section name | |
4389 | * instead | |
4390 | */ | |
ad23b723 AN |
4391 | if (ELF64_ST_TYPE(sym->st_info) == STT_SECTION && sym->st_name == 0) |
4392 | sym_name = elf_sec_name(obj, elf_sec_by_idx(obj, sym->st_shndx)); | |
c3c55696 | 4393 | else |
ad23b723 | 4394 | sym_name = elf_sym_str(obj, sym->st_name); |
c3c55696 | 4395 | sym_name = sym_name ?: "<?"; |
d859900c | 4396 | |
9c0f8cbd AN |
4397 | pr_debug("sec '%s': relo #%d: insn #%u against '%s'\n", |
4398 | relo_sec_name, i, insn_idx, sym_name); | |
666810e8 | 4399 | |
c3c55696 AN |
4400 | prog = find_prog_by_sec_insn(obj, sec_idx, insn_idx); |
4401 | if (!prog) { | |
6245947c | 4402 | pr_debug("sec '%s': relo #%d: couldn't find program in section '%s' for insn #%u, probably overridden weak function, skipping...\n", |
c3c55696 | 4403 | relo_sec_name, i, sec_name, insn_idx); |
6245947c | 4404 | continue; |
c3c55696 AN |
4405 | } |
4406 | ||
4407 | relos = libbpf_reallocarray(prog->reloc_desc, | |
4408 | prog->nr_reloc + 1, sizeof(*relos)); | |
4409 | if (!relos) | |
4410 | return -ENOMEM; | |
4411 | prog->reloc_desc = relos; | |
4412 | ||
4413 | /* adjust insn_idx to local BPF program frame of reference */ | |
4414 | insn_idx -= prog->sec_insn_off; | |
4415 | err = bpf_program__record_reloc(prog, &relos[prog->nr_reloc], | |
ad23b723 | 4416 | insn_idx, sym_name, sym, rel); |
1f8e2bcb AN |
4417 | if (err) |
4418 | return err; | |
c3c55696 AN |
4419 | |
4420 | prog->nr_reloc++; | |
34090915 WN |
4421 | } |
4422 | return 0; | |
4423 | } | |
4424 | ||
4fcac46c | 4425 | static int map_fill_btf_type_info(struct bpf_object *obj, struct bpf_map *map) |
8a138aed | 4426 | { |
aaf6886d | 4427 | int id; |
8a138aed | 4428 | |
a8fee962 AN |
4429 | if (!obj->btf) |
4430 | return -ENOENT; | |
4431 | ||
590a0088 MKL |
4432 | /* if it's BTF-defined map, we don't need to search for type IDs. |
4433 | * For struct_ops map, it does not need btf_key_type_id and | |
4434 | * btf_value_type_id. | |
4435 | */ | |
aaf6886d | 4436 | if (map->sec_idx == obj->efile.btf_maps_shndx || bpf_map__is_struct_ops(map)) |
abd29c93 AN |
4437 | return 0; |
4438 | ||
aaf6886d AN |
4439 | /* |
4440 | * LLVM annotates global data differently in BTF, that is, | |
4441 | * only as '.data', '.bss' or '.rodata'. | |
4442 | */ | |
4443 | if (!bpf_map__is_internal(map)) | |
4444 | return -ENOENT; | |
4445 | ||
4446 | id = btf__find_by_name(obj->btf, map->real_name); | |
4447 | if (id < 0) | |
4448 | return id; | |
8a138aed | 4449 | |
aaf6886d AN |
4450 | map->btf_key_type_id = 0; |
4451 | map->btf_value_type_id = id; | |
8a138aed MKL |
4452 | return 0; |
4453 | } | |
4454 | ||
97eb3138 MP |
4455 | static int bpf_get_map_info_from_fdinfo(int fd, struct bpf_map_info *info) |
4456 | { | |
4457 | char file[PATH_MAX], buff[4096]; | |
4458 | FILE *fp; | |
4459 | __u32 val; | |
4460 | int err; | |
4461 | ||
4462 | snprintf(file, sizeof(file), "/proc/%d/fdinfo/%d", getpid(), fd); | |
4463 | memset(info, 0, sizeof(*info)); | |
4464 | ||
59842c54 | 4465 | fp = fopen(file, "re"); |
97eb3138 MP |
4466 | if (!fp) { |
4467 | err = -errno; | |
4468 | pr_warn("failed to open %s: %d. No procfs support?\n", file, | |
4469 | err); | |
4470 | return err; | |
4471 | } | |
4472 | ||
4473 | while (fgets(buff, sizeof(buff), fp)) { | |
4474 | if (sscanf(buff, "map_type:\t%u", &val) == 1) | |
4475 | info->type = val; | |
4476 | else if (sscanf(buff, "key_size:\t%u", &val) == 1) | |
4477 | info->key_size = val; | |
4478 | else if (sscanf(buff, "value_size:\t%u", &val) == 1) | |
4479 | info->value_size = val; | |
4480 | else if (sscanf(buff, "max_entries:\t%u", &val) == 1) | |
4481 | info->max_entries = val; | |
4482 | else if (sscanf(buff, "map_flags:\t%i", &val) == 1) | |
4483 | info->map_flags = val; | |
4484 | } | |
4485 | ||
4486 | fclose(fp); | |
4487 | ||
4488 | return 0; | |
4489 | } | |
4490 | ||
ec41817b AN |
4491 | bool bpf_map__autocreate(const struct bpf_map *map) |
4492 | { | |
4493 | return map->autocreate; | |
4494 | } | |
4495 | ||
4496 | int bpf_map__set_autocreate(struct bpf_map *map, bool autocreate) | |
4497 | { | |
4498 | if (map->obj->loaded) | |
4499 | return libbpf_err(-EBUSY); | |
4500 | ||
4501 | map->autocreate = autocreate; | |
4502 | return 0; | |
4503 | } | |
4504 | ||
26736eb9 JK |
4505 | int bpf_map__reuse_fd(struct bpf_map *map, int fd) |
4506 | { | |
813847a3 | 4507 | struct bpf_map_info info; |
bf3f0037 | 4508 | __u32 len = sizeof(info), name_len; |
26736eb9 JK |
4509 | int new_fd, err; |
4510 | char *new_name; | |
4511 | ||
813847a3 | 4512 | memset(&info, 0, len); |
629dfc66 | 4513 | err = bpf_map_get_info_by_fd(fd, &info, &len); |
97eb3138 MP |
4514 | if (err && errno == EINVAL) |
4515 | err = bpf_get_map_info_from_fdinfo(fd, &info); | |
26736eb9 | 4516 | if (err) |
e9fc3ce9 | 4517 | return libbpf_err(err); |
26736eb9 | 4518 | |
bf3f0037 AW |
4519 | name_len = strlen(info.name); |
4520 | if (name_len == BPF_OBJ_NAME_LEN - 1 && strncmp(map->name, info.name, name_len) == 0) | |
4521 | new_name = strdup(map->name); | |
4522 | else | |
4523 | new_name = strdup(info.name); | |
4524 | ||
26736eb9 | 4525 | if (!new_name) |
e9fc3ce9 | 4526 | return libbpf_err(-errno); |
26736eb9 | 4527 | |
4aadd292 AN |
4528 | /* |
4529 | * Like dup(), but make sure new FD is >= 3 and has O_CLOEXEC set. | |
4530 | * This is similar to what we do in ensure_good_fd(), but without | |
4531 | * closing original FD. | |
4532 | */ | |
4533 | new_fd = fcntl(fd, F_DUPFD_CLOEXEC, 3); | |
d1b4574a THJ |
4534 | if (new_fd < 0) { |
4535 | err = -errno; | |
26736eb9 | 4536 | goto err_free_new_name; |
d1b4574a | 4537 | } |
26736eb9 | 4538 | |
26736eb9 | 4539 | err = zclose(map->fd); |
d1b4574a THJ |
4540 | if (err) { |
4541 | err = -errno; | |
26736eb9 | 4542 | goto err_close_new_fd; |
d1b4574a | 4543 | } |
26736eb9 JK |
4544 | free(map->name); |
4545 | ||
4546 | map->fd = new_fd; | |
4547 | map->name = new_name; | |
4548 | map->def.type = info.type; | |
4549 | map->def.key_size = info.key_size; | |
4550 | map->def.value_size = info.value_size; | |
4551 | map->def.max_entries = info.max_entries; | |
4552 | map->def.map_flags = info.map_flags; | |
4553 | map->btf_key_type_id = info.btf_key_type_id; | |
4554 | map->btf_value_type_id = info.btf_value_type_id; | |
ec6d5f47 | 4555 | map->reused = true; |
47512102 | 4556 | map->map_extra = info.map_extra; |
26736eb9 JK |
4557 | |
4558 | return 0; | |
4559 | ||
4560 | err_close_new_fd: | |
4561 | close(new_fd); | |
4562 | err_free_new_name: | |
4563 | free(new_name); | |
e9fc3ce9 | 4564 | return libbpf_err(err); |
26736eb9 JK |
4565 | } |
4566 | ||
1bdb6c9a | 4567 | __u32 bpf_map__max_entries(const struct bpf_map *map) |
1a11a4c7 | 4568 | { |
1bdb6c9a AN |
4569 | return map->def.max_entries; |
4570 | } | |
1a11a4c7 | 4571 | |
b3278099 AN |
4572 | struct bpf_map *bpf_map__inner_map(struct bpf_map *map) |
4573 | { | |
4574 | if (!bpf_map_type__is_map_in_map(map->def.type)) | |
e9fc3ce9 | 4575 | return errno = EINVAL, NULL; |
b3278099 AN |
4576 | |
4577 | return map->inner_map; | |
4578 | } | |
4579 | ||
1bdb6c9a AN |
4580 | int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries) |
4581 | { | |
597fbc46 | 4582 | if (map->obj->loaded) |
e9fc3ce9 | 4583 | return libbpf_err(-EBUSY); |
597fbc46 | 4584 | |
1a11a4c7 | 4585 | map->def.max_entries = max_entries; |
597fbc46 AN |
4586 | |
4587 | /* auto-adjust BPF ringbuf map max_entries to be a multiple of page size */ | |
b66ccae0 | 4588 | if (map_is_ringbuf(map)) |
597fbc46 AN |
4589 | map->def.max_entries = adjust_ringbuf_sz(map->def.max_entries); |
4590 | ||
1a11a4c7 AI |
4591 | return 0; |
4592 | } | |
4593 | ||
47eff617 | 4594 | static int |
fd9eef1a | 4595 | bpf_object__probe_loading(struct bpf_object *obj) |
47eff617 | 4596 | { |
47eff617 SF |
4597 | char *cp, errmsg[STRERR_BUFSIZE]; |
4598 | struct bpf_insn insns[] = { | |
4599 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
4600 | BPF_EXIT_INSN(), | |
4601 | }; | |
e32660ac | 4602 | int ret, insn_cnt = ARRAY_SIZE(insns); |
47eff617 | 4603 | |
f9bceaa5 SF |
4604 | if (obj->gen_loader) |
4605 | return 0; | |
4606 | ||
e542f2c4 AN |
4607 | ret = bump_rlimit_memlock(); |
4608 | if (ret) | |
4609 | pr_warn("Failed to bump RLIMIT_MEMLOCK (err = %d), you might need to do it explicitly!\n", ret); | |
4610 | ||
47eff617 | 4611 | /* make sure basic loading works */ |
e32660ac AN |
4612 | ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, NULL); |
4613 | if (ret < 0) | |
4614 | ret = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, NULL); | |
47eff617 | 4615 | if (ret < 0) { |
fd9eef1a EC |
4616 | ret = errno; |
4617 | cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); | |
4618 | pr_warn("Error in %s():%s(%d). Couldn't load trivial BPF " | |
4619 | "program. Make sure your kernel supports BPF " | |
4620 | "(CONFIG_BPF_SYSCALL=y) and/or that RLIMIT_MEMLOCK is " | |
4621 | "set to big enough value.\n", __func__, cp, ret); | |
4622 | return -ret; | |
47eff617 SF |
4623 | } |
4624 | close(ret); | |
4625 | ||
fd9eef1a EC |
4626 | return 0; |
4627 | } | |
4628 | ||
bb180fb2 AN |
4629 | static int probe_fd(int fd) |
4630 | { | |
4631 | if (fd >= 0) | |
4632 | close(fd); | |
4633 | return fd >= 0; | |
4634 | } | |
4635 | ||
47b6cb4d | 4636 | static int probe_kern_prog_name(void) |
fd9eef1a | 4637 | { |
1f235777 | 4638 | const size_t attr_sz = offsetofend(union bpf_attr, prog_name); |
fd9eef1a EC |
4639 | struct bpf_insn insns[] = { |
4640 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
4641 | BPF_EXIT_INSN(), | |
4642 | }; | |
1f235777 HL |
4643 | union bpf_attr attr; |
4644 | int ret; | |
4645 | ||
4646 | memset(&attr, 0, attr_sz); | |
4647 | attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; | |
4648 | attr.license = ptr_to_u64("GPL"); | |
4649 | attr.insns = ptr_to_u64(insns); | |
4650 | attr.insn_cnt = (__u32)ARRAY_SIZE(insns); | |
4651 | libbpf_strlcpy(attr.prog_name, "libbpf_nametest", sizeof(attr.prog_name)); | |
fd9eef1a EC |
4652 | |
4653 | /* make sure loading with name works */ | |
1f235777 | 4654 | ret = sys_bpf_prog_load(&attr, attr_sz, PROG_LOAD_ATTEMPTS); |
bb180fb2 | 4655 | return probe_fd(ret); |
47eff617 SF |
4656 | } |
4657 | ||
47b6cb4d | 4658 | static int probe_kern_global_data(void) |
8837fe5d | 4659 | { |
8837fe5d DB |
4660 | char *cp, errmsg[STRERR_BUFSIZE]; |
4661 | struct bpf_insn insns[] = { | |
4662 | BPF_LD_MAP_VALUE(BPF_REG_1, 0, 16), | |
4663 | BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 42), | |
4664 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
4665 | BPF_EXIT_INSN(), | |
4666 | }; | |
e32660ac | 4667 | int ret, map, insn_cnt = ARRAY_SIZE(insns); |
8837fe5d | 4668 | |
10b62d6a | 4669 | map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_global", sizeof(int), 32, 1, NULL); |
8837fe5d | 4670 | if (map < 0) { |
23ab656b THJ |
4671 | ret = -errno; |
4672 | cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); | |
be18010e | 4673 | pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n", |
23ab656b THJ |
4674 | __func__, cp, -ret); |
4675 | return ret; | |
8837fe5d DB |
4676 | } |
4677 | ||
4678 | insns[0].imm = map; | |
4679 | ||
e32660ac | 4680 | ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, NULL); |
47b6cb4d | 4681 | close(map); |
bb180fb2 | 4682 | return probe_fd(ret); |
8837fe5d DB |
4683 | } |
4684 | ||
68b08647 AN |
4685 | static int probe_kern_btf(void) |
4686 | { | |
4687 | static const char strs[] = "\0int"; | |
4688 | __u32 types[] = { | |
4689 | /* int */ | |
4690 | BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), | |
4691 | }; | |
4692 | ||
4693 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), | |
4694 | strs, sizeof(strs))); | |
4695 | } | |
4696 | ||
47b6cb4d | 4697 | static int probe_kern_btf_func(void) |
d7c4b398 | 4698 | { |
8983b731 | 4699 | static const char strs[] = "\0int\0x\0a"; |
d7c4b398 AN |
4700 | /* void x(int a) {} */ |
4701 | __u32 types[] = { | |
4702 | /* int */ | |
4703 | BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ | |
4704 | /* FUNC_PROTO */ /* [2] */ | |
4705 | BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), | |
4706 | BTF_PARAM_ENC(7, 1), | |
4707 | /* FUNC x */ /* [3] */ | |
4708 | BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2), | |
4709 | }; | |
d7c4b398 | 4710 | |
bb180fb2 AN |
4711 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), |
4712 | strs, sizeof(strs))); | |
d7c4b398 AN |
4713 | } |
4714 | ||
47b6cb4d | 4715 | static int probe_kern_btf_func_global(void) |
2d3eb67f AS |
4716 | { |
4717 | static const char strs[] = "\0int\0x\0a"; | |
4718 | /* static void x(int a) {} */ | |
4719 | __u32 types[] = { | |
4720 | /* int */ | |
4721 | BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ | |
4722 | /* FUNC_PROTO */ /* [2] */ | |
4723 | BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), | |
4724 | BTF_PARAM_ENC(7, 1), | |
4725 | /* FUNC x BTF_FUNC_GLOBAL */ /* [3] */ | |
4726 | BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, BTF_FUNC_GLOBAL), 2), | |
4727 | }; | |
2d3eb67f | 4728 | |
bb180fb2 AN |
4729 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), |
4730 | strs, sizeof(strs))); | |
2d3eb67f AS |
4731 | } |
4732 | ||
47b6cb4d | 4733 | static int probe_kern_btf_datasec(void) |
d7c4b398 | 4734 | { |
8983b731 | 4735 | static const char strs[] = "\0x\0.data"; |
d7c4b398 AN |
4736 | /* static int a; */ |
4737 | __u32 types[] = { | |
4738 | /* int */ | |
4739 | BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ | |
4740 | /* VAR x */ /* [2] */ | |
4741 | BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), | |
4742 | BTF_VAR_STATIC, | |
4743 | /* DATASEC val */ /* [3] */ | |
4744 | BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4), | |
4745 | BTF_VAR_SECINFO_ENC(2, 0, 4), | |
4746 | }; | |
cfd49210 | 4747 | |
bb180fb2 AN |
4748 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), |
4749 | strs, sizeof(strs))); | |
d7c4b398 AN |
4750 | } |
4751 | ||
22541a9e IL |
4752 | static int probe_kern_btf_float(void) |
4753 | { | |
4754 | static const char strs[] = "\0float"; | |
4755 | __u32 types[] = { | |
4756 | /* float */ | |
4757 | BTF_TYPE_FLOAT_ENC(1, 4), | |
4758 | }; | |
4759 | ||
4760 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), | |
4761 | strs, sizeof(strs))); | |
4762 | } | |
4763 | ||
223f903e | 4764 | static int probe_kern_btf_decl_tag(void) |
5b84bd10 YS |
4765 | { |
4766 | static const char strs[] = "\0tag"; | |
4767 | __u32 types[] = { | |
4768 | /* int */ | |
4769 | BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ | |
4770 | /* VAR x */ /* [2] */ | |
4771 | BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), | |
4772 | BTF_VAR_STATIC, | |
4773 | /* attr */ | |
223f903e | 4774 | BTF_TYPE_DECL_TAG_ENC(1, 2, -1), |
5b84bd10 YS |
4775 | }; |
4776 | ||
4777 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), | |
4778 | strs, sizeof(strs))); | |
4779 | } | |
4780 | ||
2dc1e488 YS |
4781 | static int probe_kern_btf_type_tag(void) |
4782 | { | |
4783 | static const char strs[] = "\0tag"; | |
4784 | __u32 types[] = { | |
4785 | /* int */ | |
4786 | BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ | |
4787 | /* attr */ | |
4788 | BTF_TYPE_TYPE_TAG_ENC(1, 1), /* [2] */ | |
4789 | /* ptr */ | |
4790 | BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 2), /* [3] */ | |
4791 | }; | |
4792 | ||
4793 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), | |
4794 | strs, sizeof(strs))); | |
4795 | } | |
4796 | ||
47b6cb4d | 4797 | static int probe_kern_array_mmap(void) |
7fe74b43 | 4798 | { |
a9606f40 AN |
4799 | LIBBPF_OPTS(bpf_map_create_opts, opts, .map_flags = BPF_F_MMAPABLE); |
4800 | int fd; | |
7fe74b43 | 4801 | |
10b62d6a | 4802 | fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_mmap", sizeof(int), sizeof(int), 1, &opts); |
a9606f40 | 4803 | return probe_fd(fd); |
7fe74b43 AN |
4804 | } |
4805 | ||
47b6cb4d | 4806 | static int probe_kern_exp_attach_type(void) |
25498a19 | 4807 | { |
e32660ac | 4808 | LIBBPF_OPTS(bpf_prog_load_opts, opts, .expected_attach_type = BPF_CGROUP_INET_SOCK_CREATE); |
25498a19 AN |
4809 | struct bpf_insn insns[] = { |
4810 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
4811 | BPF_EXIT_INSN(), | |
4812 | }; | |
e32660ac | 4813 | int fd, insn_cnt = ARRAY_SIZE(insns); |
25498a19 | 4814 | |
25498a19 AN |
4815 | /* use any valid combination of program type and (optional) |
4816 | * non-zero expected attach type (i.e., not a BPF_CGROUP_INET_INGRESS) | |
4817 | * to see if kernel supports expected_attach_type field for | |
4818 | * BPF_PROG_LOAD command | |
4819 | */ | |
e32660ac AN |
4820 | fd = bpf_prog_load(BPF_PROG_TYPE_CGROUP_SOCK, NULL, "GPL", insns, insn_cnt, &opts); |
4821 | return probe_fd(fd); | |
25498a19 AN |
4822 | } |
4823 | ||
109cea5a AN |
4824 | static int probe_kern_probe_read_kernel(void) |
4825 | { | |
109cea5a AN |
4826 | struct bpf_insn insns[] = { |
4827 | BPF_MOV64_REG(BPF_REG_1, BPF_REG_10), /* r1 = r10 (fp) */ | |
4828 | BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8), /* r1 += -8 */ | |
4829 | BPF_MOV64_IMM(BPF_REG_2, 8), /* r2 = 8 */ | |
4830 | BPF_MOV64_IMM(BPF_REG_3, 0), /* r3 = 0 */ | |
4831 | BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_probe_read_kernel), | |
4832 | BPF_EXIT_INSN(), | |
4833 | }; | |
e32660ac | 4834 | int fd, insn_cnt = ARRAY_SIZE(insns); |
109cea5a | 4835 | |
d252a4a4 | 4836 | fd = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, NULL); |
e32660ac | 4837 | return probe_fd(fd); |
109cea5a AN |
4838 | } |
4839 | ||
5d23328d YZ |
4840 | static int probe_prog_bind_map(void) |
4841 | { | |
5d23328d YZ |
4842 | char *cp, errmsg[STRERR_BUFSIZE]; |
4843 | struct bpf_insn insns[] = { | |
4844 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
4845 | BPF_EXIT_INSN(), | |
4846 | }; | |
e32660ac | 4847 | int ret, map, prog, insn_cnt = ARRAY_SIZE(insns); |
5d23328d | 4848 | |
10b62d6a | 4849 | map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_det_bind", sizeof(int), 32, 1, NULL); |
5d23328d YZ |
4850 | if (map < 0) { |
4851 | ret = -errno; | |
4852 | cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); | |
4853 | pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n", | |
4854 | __func__, cp, -ret); | |
4855 | return ret; | |
4856 | } | |
4857 | ||
e32660ac | 4858 | prog = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, NULL); |
5d23328d YZ |
4859 | if (prog < 0) { |
4860 | close(map); | |
4861 | return 0; | |
4862 | } | |
4863 | ||
4864 | ret = bpf_prog_bind_map(prog, map, NULL); | |
4865 | ||
4866 | close(map); | |
4867 | close(prog); | |
4868 | ||
4869 | return ret >= 0; | |
4870 | } | |
4871 | ||
4f33a53d AN |
4872 | static int probe_module_btf(void) |
4873 | { | |
4874 | static const char strs[] = "\0int"; | |
4875 | __u32 types[] = { | |
4876 | /* int */ | |
4877 | BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), | |
4878 | }; | |
4879 | struct bpf_btf_info info; | |
4880 | __u32 len = sizeof(info); | |
4881 | char name[16]; | |
4882 | int fd, err; | |
4883 | ||
4884 | fd = libbpf__load_raw_btf((char *)types, sizeof(types), strs, sizeof(strs)); | |
4885 | if (fd < 0) | |
4886 | return 0; /* BTF not supported at all */ | |
4887 | ||
4888 | memset(&info, 0, sizeof(info)); | |
4889 | info.name = ptr_to_u64(name); | |
4890 | info.name_len = sizeof(name); | |
4891 | ||
4892 | /* check that BPF_OBJ_GET_INFO_BY_FD supports specifying name pointer; | |
4893 | * kernel's module BTF support coincides with support for | |
4894 | * name/name_len fields in struct bpf_btf_info. | |
4895 | */ | |
629dfc66 | 4896 | err = bpf_btf_get_info_by_fd(fd, &info, &len); |
4f33a53d AN |
4897 | close(fd); |
4898 | return !err; | |
4899 | } | |
4900 | ||
668ace0e AN |
4901 | static int probe_perf_link(void) |
4902 | { | |
668ace0e AN |
4903 | struct bpf_insn insns[] = { |
4904 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
4905 | BPF_EXIT_INSN(), | |
4906 | }; | |
4907 | int prog_fd, link_fd, err; | |
4908 | ||
e32660ac AN |
4909 | prog_fd = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", |
4910 | insns, ARRAY_SIZE(insns), NULL); | |
668ace0e AN |
4911 | if (prog_fd < 0) |
4912 | return -errno; | |
4913 | ||
4914 | /* use invalid perf_event FD to get EBADF, if link is supported; | |
4915 | * otherwise EINVAL should be returned | |
4916 | */ | |
4917 | link_fd = bpf_link_create(prog_fd, -1, BPF_PERF_EVENT, NULL); | |
4918 | err = -errno; /* close() can clobber errno */ | |
4919 | ||
4920 | if (link_fd >= 0) | |
4921 | close(link_fd); | |
4922 | close(prog_fd); | |
4923 | ||
4924 | return link_fd < 0 && err == -EBADF; | |
4925 | } | |
4926 | ||
7e1b4681 JO |
4927 | static int probe_uprobe_multi_link(void) |
4928 | { | |
4929 | LIBBPF_OPTS(bpf_prog_load_opts, load_opts, | |
4930 | .expected_attach_type = BPF_TRACE_UPROBE_MULTI, | |
4931 | ); | |
4932 | LIBBPF_OPTS(bpf_link_create_opts, link_opts); | |
4933 | struct bpf_insn insns[] = { | |
4934 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
4935 | BPF_EXIT_INSN(), | |
4936 | }; | |
4937 | int prog_fd, link_fd, err; | |
4938 | unsigned long offset = 0; | |
4939 | ||
4940 | prog_fd = bpf_prog_load(BPF_PROG_TYPE_KPROBE, NULL, "GPL", | |
4941 | insns, ARRAY_SIZE(insns), &load_opts); | |
4942 | if (prog_fd < 0) | |
4943 | return -errno; | |
4944 | ||
4945 | /* Creating uprobe in '/' binary should fail with -EBADF. */ | |
4946 | link_opts.uprobe_multi.path = "/"; | |
4947 | link_opts.uprobe_multi.offsets = &offset; | |
4948 | link_opts.uprobe_multi.cnt = 1; | |
4949 | ||
4950 | link_fd = bpf_link_create(prog_fd, -1, BPF_TRACE_UPROBE_MULTI, &link_opts); | |
4951 | err = -errno; /* close() can clobber errno */ | |
4952 | ||
4953 | if (link_fd >= 0) | |
4954 | close(link_fd); | |
4955 | close(prog_fd); | |
4956 | ||
4957 | return link_fd < 0 && err == -EBADF; | |
4958 | } | |
4959 | ||
2e4913e0 AN |
4960 | static int probe_kern_bpf_cookie(void) |
4961 | { | |
4962 | struct bpf_insn insns[] = { | |
4963 | BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_attach_cookie), | |
4964 | BPF_EXIT_INSN(), | |
4965 | }; | |
4966 | int ret, insn_cnt = ARRAY_SIZE(insns); | |
4967 | ||
4968 | ret = bpf_prog_load(BPF_PROG_TYPE_KPROBE, NULL, "GPL", insns, insn_cnt, NULL); | |
4969 | return probe_fd(ret); | |
4970 | } | |
4971 | ||
f2a62588 YS |
4972 | static int probe_kern_btf_enum64(void) |
4973 | { | |
4974 | static const char strs[] = "\0enum64"; | |
4975 | __u32 types[] = { | |
4976 | BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_ENUM64, 0, 0), 8), | |
4977 | }; | |
4978 | ||
4979 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), | |
4980 | strs, sizeof(strs))); | |
4981 | } | |
4982 | ||
708ac5be AN |
4983 | static int probe_kern_syscall_wrapper(void); |
4984 | ||
47b6cb4d AN |
4985 | enum kern_feature_result { |
4986 | FEAT_UNKNOWN = 0, | |
4987 | FEAT_SUPPORTED = 1, | |
4988 | FEAT_MISSING = 2, | |
4989 | }; | |
4990 | ||
4991 | typedef int (*feature_probe_fn)(void); | |
4992 | ||
4993 | static struct kern_feature_desc { | |
4994 | const char *desc; | |
4995 | feature_probe_fn probe; | |
4996 | enum kern_feature_result res; | |
4997 | } feature_probes[__FEAT_CNT] = { | |
4998 | [FEAT_PROG_NAME] = { | |
4999 | "BPF program name", probe_kern_prog_name, | |
5000 | }, | |
5001 | [FEAT_GLOBAL_DATA] = { | |
5002 | "global variables", probe_kern_global_data, | |
5003 | }, | |
68b08647 AN |
5004 | [FEAT_BTF] = { |
5005 | "minimal BTF", probe_kern_btf, | |
5006 | }, | |
47b6cb4d AN |
5007 | [FEAT_BTF_FUNC] = { |
5008 | "BTF functions", probe_kern_btf_func, | |
5009 | }, | |
5010 | [FEAT_BTF_GLOBAL_FUNC] = { | |
5011 | "BTF global function", probe_kern_btf_func_global, | |
5012 | }, | |
5013 | [FEAT_BTF_DATASEC] = { | |
5014 | "BTF data section and variable", probe_kern_btf_datasec, | |
5015 | }, | |
5016 | [FEAT_ARRAY_MMAP] = { | |
5017 | "ARRAY map mmap()", probe_kern_array_mmap, | |
5018 | }, | |
5019 | [FEAT_EXP_ATTACH_TYPE] = { | |
5020 | "BPF_PROG_LOAD expected_attach_type attribute", | |
5021 | probe_kern_exp_attach_type, | |
5022 | }, | |
109cea5a AN |
5023 | [FEAT_PROBE_READ_KERN] = { |
5024 | "bpf_probe_read_kernel() helper", probe_kern_probe_read_kernel, | |
5d23328d YZ |
5025 | }, |
5026 | [FEAT_PROG_BIND_MAP] = { | |
5027 | "BPF_PROG_BIND_MAP support", probe_prog_bind_map, | |
4f33a53d AN |
5028 | }, |
5029 | [FEAT_MODULE_BTF] = { | |
5030 | "module BTF support", probe_module_btf, | |
5031 | }, | |
22541a9e IL |
5032 | [FEAT_BTF_FLOAT] = { |
5033 | "BTF_KIND_FLOAT support", probe_kern_btf_float, | |
5034 | }, | |
668ace0e AN |
5035 | [FEAT_PERF_LINK] = { |
5036 | "BPF perf link support", probe_perf_link, | |
5037 | }, | |
223f903e YS |
5038 | [FEAT_BTF_DECL_TAG] = { |
5039 | "BTF_KIND_DECL_TAG support", probe_kern_btf_decl_tag, | |
5b84bd10 | 5040 | }, |
2dc1e488 YS |
5041 | [FEAT_BTF_TYPE_TAG] = { |
5042 | "BTF_KIND_TYPE_TAG support", probe_kern_btf_type_tag, | |
5043 | }, | |
e542f2c4 AN |
5044 | [FEAT_MEMCG_ACCOUNT] = { |
5045 | "memcg-based memory accounting", probe_memcg_account, | |
5046 | }, | |
2e4913e0 AN |
5047 | [FEAT_BPF_COOKIE] = { |
5048 | "BPF cookie support", probe_kern_bpf_cookie, | |
5049 | }, | |
f2a62588 YS |
5050 | [FEAT_BTF_ENUM64] = { |
5051 | "BTF_KIND_ENUM64 support", probe_kern_btf_enum64, | |
5052 | }, | |
708ac5be AN |
5053 | [FEAT_SYSCALL_WRAPPER] = { |
5054 | "Kernel using syscall wrapper", probe_kern_syscall_wrapper, | |
5055 | }, | |
7e1b4681 JO |
5056 | [FEAT_UPROBE_MULTI_LINK] = { |
5057 | "BPF multi-uprobe link support", probe_uprobe_multi_link, | |
5058 | }, | |
47b6cb4d | 5059 | }; |
8837fe5d | 5060 | |
e542f2c4 | 5061 | bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id) |
47b6cb4d AN |
5062 | { |
5063 | struct kern_feature_desc *feat = &feature_probes[feat_id]; | |
5064 | int ret; | |
5065 | ||
e542f2c4 | 5066 | if (obj && obj->gen_loader) |
67234743 AS |
5067 | /* To generate loader program assume the latest kernel |
5068 | * to avoid doing extra prog_load, map_create syscalls. | |
5069 | */ | |
5070 | return true; | |
5071 | ||
47b6cb4d AN |
5072 | if (READ_ONCE(feat->res) == FEAT_UNKNOWN) { |
5073 | ret = feat->probe(); | |
5074 | if (ret > 0) { | |
5075 | WRITE_ONCE(feat->res, FEAT_SUPPORTED); | |
5076 | } else if (ret == 0) { | |
5077 | WRITE_ONCE(feat->res, FEAT_MISSING); | |
5078 | } else { | |
5079 | pr_warn("Detection of kernel %s support failed: %d\n", feat->desc, ret); | |
5080 | WRITE_ONCE(feat->res, FEAT_MISSING); | |
5081 | } | |
8837fe5d DB |
5082 | } |
5083 | ||
47b6cb4d | 5084 | return READ_ONCE(feat->res) == FEAT_SUPPORTED; |
47eff617 SF |
5085 | } |
5086 | ||
57a00f41 THJ |
5087 | static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd) |
5088 | { | |
813847a3 | 5089 | struct bpf_map_info map_info; |
57a00f41 | 5090 | char msg[STRERR_BUFSIZE]; |
813847a3 | 5091 | __u32 map_info_len = sizeof(map_info); |
97eb3138 | 5092 | int err; |
57a00f41 | 5093 | |
813847a3 | 5094 | memset(&map_info, 0, map_info_len); |
629dfc66 | 5095 | err = bpf_map_get_info_by_fd(map_fd, &map_info, &map_info_len); |
97eb3138 MP |
5096 | if (err && errno == EINVAL) |
5097 | err = bpf_get_map_info_from_fdinfo(map_fd, &map_info); | |
5098 | if (err) { | |
5099 | pr_warn("failed to get map info for map FD %d: %s\n", map_fd, | |
5100 | libbpf_strerror_r(errno, msg, sizeof(msg))); | |
57a00f41 THJ |
5101 | return false; |
5102 | } | |
5103 | ||
5104 | return (map_info.type == map->def.type && | |
5105 | map_info.key_size == map->def.key_size && | |
5106 | map_info.value_size == map->def.value_size && | |
5107 | map_info.max_entries == map->def.max_entries && | |
47512102 JK |
5108 | map_info.map_flags == map->def.map_flags && |
5109 | map_info.map_extra == map->map_extra); | |
57a00f41 THJ |
5110 | } |
5111 | ||
5112 | static int | |
5113 | bpf_object__reuse_map(struct bpf_map *map) | |
5114 | { | |
5115 | char *cp, errmsg[STRERR_BUFSIZE]; | |
5116 | int err, pin_fd; | |
5117 | ||
5118 | pin_fd = bpf_obj_get(map->pin_path); | |
5119 | if (pin_fd < 0) { | |
5120 | err = -errno; | |
5121 | if (err == -ENOENT) { | |
5122 | pr_debug("found no pinned map to reuse at '%s'\n", | |
5123 | map->pin_path); | |
5124 | return 0; | |
5125 | } | |
5126 | ||
5127 | cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); | |
5128 | pr_warn("couldn't retrieve pinned map '%s': %s\n", | |
5129 | map->pin_path, cp); | |
5130 | return err; | |
5131 | } | |
5132 | ||
5133 | if (!map_is_reuse_compat(map, pin_fd)) { | |
5134 | pr_warn("couldn't reuse pinned map at '%s': parameter mismatch\n", | |
5135 | map->pin_path); | |
5136 | close(pin_fd); | |
5137 | return -EINVAL; | |
5138 | } | |
5139 | ||
5140 | err = bpf_map__reuse_fd(map, pin_fd); | |
d0f325c3 | 5141 | close(pin_fd); |
e3ba8e4e | 5142 | if (err) |
57a00f41 | 5143 | return err; |
e3ba8e4e | 5144 | |
57a00f41 THJ |
5145 | map->pinned = true; |
5146 | pr_debug("reused pinned map at '%s'\n", map->pin_path); | |
5147 | ||
5148 | return 0; | |
5149 | } | |
5150 | ||
d859900c DB |
5151 | static int |
5152 | bpf_object__populate_internal_map(struct bpf_object *obj, struct bpf_map *map) | |
5153 | { | |
166750bc | 5154 | enum libbpf_map_type map_type = map->libbpf_type; |
d859900c DB |
5155 | char *cp, errmsg[STRERR_BUFSIZE]; |
5156 | int err, zero = 0; | |
d859900c | 5157 | |
67234743 AS |
5158 | if (obj->gen_loader) { |
5159 | bpf_gen__map_update_elem(obj->gen_loader, map - obj->maps, | |
5160 | map->mmaped, map->def.value_size); | |
5161 | if (map_type == LIBBPF_MAP_RODATA || map_type == LIBBPF_MAP_KCONFIG) | |
5162 | bpf_gen__map_freeze(obj->gen_loader, map - obj->maps); | |
5163 | return 0; | |
5164 | } | |
eba9c5f4 AN |
5165 | err = bpf_map_update_elem(map->fd, &zero, map->mmaped, 0); |
5166 | if (err) { | |
5167 | err = -errno; | |
5168 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
5169 | pr_warn("Error setting initial map(%s) contents: %s\n", | |
5170 | map->name, cp); | |
5171 | return err; | |
5172 | } | |
d859900c | 5173 | |
81bfdd08 AN |
5174 | /* Freeze .rodata and .kconfig map as read-only from syscall side. */ |
5175 | if (map_type == LIBBPF_MAP_RODATA || map_type == LIBBPF_MAP_KCONFIG) { | |
d859900c DB |
5176 | err = bpf_map_freeze(map->fd); |
5177 | if (err) { | |
eba9c5f4 AN |
5178 | err = -errno; |
5179 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
be18010e KW |
5180 | pr_warn("Error freezing map(%s) as read-only: %s\n", |
5181 | map->name, cp); | |
eba9c5f4 | 5182 | return err; |
d859900c DB |
5183 | } |
5184 | } | |
eba9c5f4 | 5185 | return 0; |
d859900c DB |
5186 | } |
5187 | ||
2d39d7c5 AN |
5188 | static void bpf_map__destroy(struct bpf_map *map); |
5189 | ||
67234743 | 5190 | static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, bool is_inner) |
2d39d7c5 | 5191 | { |
992c4225 | 5192 | LIBBPF_OPTS(bpf_map_create_opts, create_attr); |
2d39d7c5 | 5193 | struct bpf_map_def *def = &map->def; |
992c4225 | 5194 | const char *map_name = NULL; |
a21ab4c5 | 5195 | int err = 0; |
2d39d7c5 | 5196 | |
9ca1f56a | 5197 | if (kernel_supports(obj, FEAT_PROG_NAME)) |
992c4225 | 5198 | map_name = map->name; |
2d39d7c5 | 5199 | create_attr.map_ifindex = map->map_ifindex; |
2d39d7c5 | 5200 | create_attr.map_flags = def->map_flags; |
1bdb6c9a | 5201 | create_attr.numa_node = map->numa_node; |
47512102 | 5202 | create_attr.map_extra = map->map_extra; |
2d39d7c5 | 5203 | |
2d39d7c5 | 5204 | if (bpf_map__is_struct_ops(map)) |
992c4225 | 5205 | create_attr.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; |
2d39d7c5 | 5206 | |
262cfb74 | 5207 | if (obj->btf && btf__fd(obj->btf) >= 0) { |
2d39d7c5 AN |
5208 | create_attr.btf_fd = btf__fd(obj->btf); |
5209 | create_attr.btf_key_type_id = map->btf_key_type_id; | |
5210 | create_attr.btf_value_type_id = map->btf_value_type_id; | |
5211 | } | |
5212 | ||
646f02ff AN |
5213 | if (bpf_map_type__is_map_in_map(def->type)) { |
5214 | if (map->inner_map) { | |
67234743 | 5215 | err = bpf_object__create_map(obj, map->inner_map, true); |
646f02ff AN |
5216 | if (err) { |
5217 | pr_warn("map '%s': failed to create inner map: %d\n", | |
5218 | map->name, err); | |
5219 | return err; | |
5220 | } | |
5221 | map->inner_map_fd = bpf_map__fd(map->inner_map); | |
5222 | } | |
5223 | if (map->inner_map_fd >= 0) | |
5224 | create_attr.inner_map_fd = map->inner_map_fd; | |
5225 | } | |
5226 | ||
f7310523 HC |
5227 | switch (def->type) { |
5228 | case BPF_MAP_TYPE_PERF_EVENT_ARRAY: | |
5229 | case BPF_MAP_TYPE_CGROUP_ARRAY: | |
5230 | case BPF_MAP_TYPE_STACK_TRACE: | |
5231 | case BPF_MAP_TYPE_ARRAY_OF_MAPS: | |
5232 | case BPF_MAP_TYPE_HASH_OF_MAPS: | |
5233 | case BPF_MAP_TYPE_DEVMAP: | |
5234 | case BPF_MAP_TYPE_DEVMAP_HASH: | |
5235 | case BPF_MAP_TYPE_CPUMAP: | |
5236 | case BPF_MAP_TYPE_XSKMAP: | |
5237 | case BPF_MAP_TYPE_SOCKMAP: | |
5238 | case BPF_MAP_TYPE_SOCKHASH: | |
5239 | case BPF_MAP_TYPE_QUEUE: | |
5240 | case BPF_MAP_TYPE_STACK: | |
f7310523 HC |
5241 | create_attr.btf_fd = 0; |
5242 | create_attr.btf_key_type_id = 0; | |
5243 | create_attr.btf_value_type_id = 0; | |
5244 | map->btf_key_type_id = 0; | |
5245 | map->btf_value_type_id = 0; | |
5246 | default: | |
5247 | break; | |
5248 | } | |
5249 | ||
67234743 | 5250 | if (obj->gen_loader) { |
992c4225 | 5251 | bpf_gen__map_create(obj->gen_loader, def->type, map_name, |
a4fbfdd7 | 5252 | def->key_size, def->value_size, def->max_entries, |
992c4225 | 5253 | &create_attr, is_inner ? -1 : map - obj->maps); |
67234743 AS |
5254 | /* Pretend to have valid FD to pass various fd >= 0 checks. |
5255 | * This fd == 0 will not be used with any syscall and will be reset to -1 eventually. | |
5256 | */ | |
5257 | map->fd = 0; | |
5258 | } else { | |
992c4225 AN |
5259 | map->fd = bpf_map_create(def->type, map_name, |
5260 | def->key_size, def->value_size, | |
a4fbfdd7 | 5261 | def->max_entries, &create_attr); |
67234743 | 5262 | } |
2d39d7c5 AN |
5263 | if (map->fd < 0 && (create_attr.btf_key_type_id || |
5264 | create_attr.btf_value_type_id)) { | |
5265 | char *cp, errmsg[STRERR_BUFSIZE]; | |
2d39d7c5 | 5266 | |
a21ab4c5 | 5267 | err = -errno; |
2d39d7c5 AN |
5268 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); |
5269 | pr_warn("Error in bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n", | |
5270 | map->name, cp, err); | |
5271 | create_attr.btf_fd = 0; | |
5272 | create_attr.btf_key_type_id = 0; | |
5273 | create_attr.btf_value_type_id = 0; | |
5274 | map->btf_key_type_id = 0; | |
5275 | map->btf_value_type_id = 0; | |
992c4225 AN |
5276 | map->fd = bpf_map_create(def->type, map_name, |
5277 | def->key_size, def->value_size, | |
a4fbfdd7 | 5278 | def->max_entries, &create_attr); |
2d39d7c5 AN |
5279 | } |
5280 | ||
a21ab4c5 | 5281 | err = map->fd < 0 ? -errno : 0; |
2d39d7c5 | 5282 | |
646f02ff | 5283 | if (bpf_map_type__is_map_in_map(def->type) && map->inner_map) { |
67234743 AS |
5284 | if (obj->gen_loader) |
5285 | map->inner_map->fd = -1; | |
646f02ff AN |
5286 | bpf_map__destroy(map->inner_map); |
5287 | zfree(&map->inner_map); | |
5288 | } | |
5289 | ||
a21ab4c5 | 5290 | return err; |
2d39d7c5 AN |
5291 | } |
5292 | ||
341ac5ff | 5293 | static int init_map_in_map_slots(struct bpf_object *obj, struct bpf_map *map) |
a0f2b7ac HL |
5294 | { |
5295 | const struct bpf_map *targ_map; | |
5296 | unsigned int i; | |
67234743 | 5297 | int fd, err = 0; |
a0f2b7ac HL |
5298 | |
5299 | for (i = 0; i < map->init_slots_sz; i++) { | |
5300 | if (!map->init_slots[i]) | |
5301 | continue; | |
5302 | ||
5303 | targ_map = map->init_slots[i]; | |
5304 | fd = bpf_map__fd(targ_map); | |
341ac5ff | 5305 | |
67234743 | 5306 | if (obj->gen_loader) { |
be05c944 AS |
5307 | bpf_gen__populate_outer_map(obj->gen_loader, |
5308 | map - obj->maps, i, | |
5309 | targ_map - obj->maps); | |
67234743 AS |
5310 | } else { |
5311 | err = bpf_map_update_elem(map->fd, &i, &fd, 0); | |
5312 | } | |
a0f2b7ac HL |
5313 | if (err) { |
5314 | err = -errno; | |
5315 | pr_warn("map '%s': failed to initialize slot [%d] to map '%s' fd=%d: %d\n", | |
341ac5ff | 5316 | map->name, i, targ_map->name, fd, err); |
a0f2b7ac HL |
5317 | return err; |
5318 | } | |
5319 | pr_debug("map '%s': slot [%d] set to map '%s' fd=%d\n", | |
5320 | map->name, i, targ_map->name, fd); | |
5321 | } | |
5322 | ||
5323 | zfree(&map->init_slots); | |
5324 | map->init_slots_sz = 0; | |
5325 | ||
5326 | return 0; | |
5327 | } | |
5328 | ||
341ac5ff HC |
5329 | static int init_prog_array_slots(struct bpf_object *obj, struct bpf_map *map) |
5330 | { | |
5331 | const struct bpf_program *targ_prog; | |
5332 | unsigned int i; | |
5333 | int fd, err; | |
5334 | ||
5335 | if (obj->gen_loader) | |
5336 | return -ENOTSUP; | |
5337 | ||
5338 | for (i = 0; i < map->init_slots_sz; i++) { | |
5339 | if (!map->init_slots[i]) | |
5340 | continue; | |
5341 | ||
5342 | targ_prog = map->init_slots[i]; | |
5343 | fd = bpf_program__fd(targ_prog); | |
5344 | ||
5345 | err = bpf_map_update_elem(map->fd, &i, &fd, 0); | |
5346 | if (err) { | |
5347 | err = -errno; | |
5348 | pr_warn("map '%s': failed to initialize slot [%d] to prog '%s' fd=%d: %d\n", | |
5349 | map->name, i, targ_prog->name, fd, err); | |
5350 | return err; | |
5351 | } | |
5352 | pr_debug("map '%s': slot [%d] set to prog '%s' fd=%d\n", | |
5353 | map->name, i, targ_prog->name, fd); | |
5354 | } | |
5355 | ||
5356 | zfree(&map->init_slots); | |
5357 | map->init_slots_sz = 0; | |
5358 | ||
5359 | return 0; | |
5360 | } | |
5361 | ||
5362 | static int bpf_object_init_prog_arrays(struct bpf_object *obj) | |
5363 | { | |
5364 | struct bpf_map *map; | |
5365 | int i, err; | |
5366 | ||
5367 | for (i = 0; i < obj->nr_maps; i++) { | |
5368 | map = &obj->maps[i]; | |
5369 | ||
5370 | if (!map->init_slots_sz || map->def.type != BPF_MAP_TYPE_PROG_ARRAY) | |
5371 | continue; | |
5372 | ||
5373 | err = init_prog_array_slots(obj, map); | |
5374 | if (err < 0) { | |
5375 | zclose(map->fd); | |
5376 | return err; | |
5377 | } | |
5378 | } | |
5379 | return 0; | |
5380 | } | |
5381 | ||
a4fbfdd7 ST |
5382 | static int map_set_def_max_entries(struct bpf_map *map) |
5383 | { | |
5384 | if (map->def.type == BPF_MAP_TYPE_PERF_EVENT_ARRAY && !map->def.max_entries) { | |
5385 | int nr_cpus; | |
5386 | ||
5387 | nr_cpus = libbpf_num_possible_cpus(); | |
5388 | if (nr_cpus < 0) { | |
5389 | pr_warn("map '%s': failed to determine number of system CPUs: %d\n", | |
5390 | map->name, nr_cpus); | |
5391 | return nr_cpus; | |
5392 | } | |
5393 | pr_debug("map '%s': setting size to %d\n", map->name, nr_cpus); | |
5394 | map->def.max_entries = nr_cpus; | |
5395 | } | |
5396 | ||
5397 | return 0; | |
5398 | } | |
5399 | ||
52d3352e WN |
5400 | static int |
5401 | bpf_object__create_maps(struct bpf_object *obj) | |
5402 | { | |
2d39d7c5 AN |
5403 | struct bpf_map *map; |
5404 | char *cp, errmsg[STRERR_BUFSIZE]; | |
5405 | unsigned int i, j; | |
8a138aed | 5406 | int err; |
043c5bb3 | 5407 | bool retried; |
52d3352e | 5408 | |
9d759a9b | 5409 | for (i = 0; i < obj->nr_maps; i++) { |
2d39d7c5 | 5410 | map = &obj->maps[i]; |
8a138aed | 5411 | |
16e0c35c AN |
5412 | /* To support old kernels, we skip creating global data maps |
5413 | * (.rodata, .data, .kconfig, etc); later on, during program | |
5414 | * loading, if we detect that at least one of the to-be-loaded | |
5415 | * programs is referencing any global data map, we'll error | |
5416 | * out with program name and relocation index logged. | |
5417 | * This approach allows to accommodate Clang emitting | |
5418 | * unnecessary .rodata.str1.1 sections for string literals, | |
5419 | * but also it allows to have CO-RE applications that use | |
5420 | * global variables in some of BPF programs, but not others. | |
5421 | * If those global variable-using programs are not loaded at | |
5422 | * runtime due to bpf_program__set_autoload(prog, false), | |
5423 | * bpf_object loading will succeed just fine even on old | |
5424 | * kernels. | |
5425 | */ | |
ec41817b AN |
5426 | if (bpf_map__is_internal(map) && !kernel_supports(obj, FEAT_GLOBAL_DATA)) |
5427 | map->autocreate = false; | |
5428 | ||
5429 | if (!map->autocreate) { | |
5430 | pr_debug("map '%s': skipped auto-creating...\n", map->name); | |
16e0c35c | 5431 | continue; |
229fae38 | 5432 | } |
16e0c35c | 5433 | |
a4fbfdd7 ST |
5434 | err = map_set_def_max_entries(map); |
5435 | if (err) | |
5436 | goto err_out; | |
5437 | ||
043c5bb3 MP |
5438 | retried = false; |
5439 | retry: | |
57a00f41 THJ |
5440 | if (map->pin_path) { |
5441 | err = bpf_object__reuse_map(map); | |
5442 | if (err) { | |
2d39d7c5 | 5443 | pr_warn("map '%s': error reusing pinned map\n", |
57a00f41 | 5444 | map->name); |
2d39d7c5 | 5445 | goto err_out; |
57a00f41 | 5446 | } |
043c5bb3 MP |
5447 | if (retried && map->fd < 0) { |
5448 | pr_warn("map '%s': cannot find pinned map\n", | |
5449 | map->name); | |
5450 | err = -ENOENT; | |
5451 | goto err_out; | |
5452 | } | |
57a00f41 THJ |
5453 | } |
5454 | ||
26736eb9 | 5455 | if (map->fd >= 0) { |
2d39d7c5 | 5456 | pr_debug("map '%s': skipping creation (preset fd=%d)\n", |
26736eb9 | 5457 | map->name, map->fd); |
2c193d32 | 5458 | } else { |
67234743 | 5459 | err = bpf_object__create_map(obj, map, false); |
2c193d32 | 5460 | if (err) |
d859900c | 5461 | goto err_out; |
d859900c | 5462 | |
2c193d32 HL |
5463 | pr_debug("map '%s': created successfully, fd=%d\n", |
5464 | map->name, map->fd); | |
646f02ff | 5465 | |
2c193d32 HL |
5466 | if (bpf_map__is_internal(map)) { |
5467 | err = bpf_object__populate_internal_map(obj, map); | |
5468 | if (err < 0) { | |
5469 | zclose(map->fd); | |
5470 | goto err_out; | |
5471 | } | |
d859900c | 5472 | } |
646f02ff | 5473 | |
341ac5ff HC |
5474 | if (map->init_slots_sz && map->def.type != BPF_MAP_TYPE_PROG_ARRAY) { |
5475 | err = init_map_in_map_slots(obj, map); | |
2c193d32 HL |
5476 | if (err < 0) { |
5477 | zclose(map->fd); | |
646f02ff AN |
5478 | goto err_out; |
5479 | } | |
646f02ff | 5480 | } |
646f02ff AN |
5481 | } |
5482 | ||
57a00f41 THJ |
5483 | if (map->pin_path && !map->pinned) { |
5484 | err = bpf_map__pin(map, NULL); | |
5485 | if (err) { | |
043c5bb3 MP |
5486 | zclose(map->fd); |
5487 | if (!retried && err == -EEXIST) { | |
5488 | retried = true; | |
5489 | goto retry; | |
5490 | } | |
2d39d7c5 AN |
5491 | pr_warn("map '%s': failed to auto-pin at '%s': %d\n", |
5492 | map->name, map->pin_path, err); | |
2d39d7c5 | 5493 | goto err_out; |
57a00f41 THJ |
5494 | } |
5495 | } | |
52d3352e WN |
5496 | } |
5497 | ||
52d3352e | 5498 | return 0; |
2d39d7c5 AN |
5499 | |
5500 | err_out: | |
5501 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
5502 | pr_warn("map '%s': failed to create: %s(%d)\n", map->name, cp, err); | |
5503 | pr_perm_msg(err); | |
5504 | for (j = 0; j < i; j++) | |
5505 | zclose(obj->maps[j].fd); | |
5506 | return err; | |
52d3352e WN |
5507 | } |
5508 | ||
ddc7c304 AN |
5509 | static bool bpf_core_is_flavor_sep(const char *s) |
5510 | { | |
5511 | /* check X___Y name pattern, where X and Y are not underscores */ | |
5512 | return s[0] != '_' && /* X */ | |
5513 | s[1] == '_' && s[2] == '_' && s[3] == '_' && /* ___ */ | |
5514 | s[4] != '_'; /* Y */ | |
5515 | } | |
5516 | ||
5517 | /* Given 'some_struct_name___with_flavor' return the length of a name prefix | |
5518 | * before last triple underscore. Struct name part after last triple | |
5519 | * underscore is ignored by BPF CO-RE relocation during relocation matching. | |
5520 | */ | |
b0588390 | 5521 | size_t bpf_core_essential_name_len(const char *name) |
ddc7c304 AN |
5522 | { |
5523 | size_t n = strlen(name); | |
5524 | int i; | |
5525 | ||
5526 | for (i = n - 5; i >= 0; i--) { | |
5527 | if (bpf_core_is_flavor_sep(name + i)) | |
5528 | return i + 1; | |
5529 | } | |
5530 | return n; | |
5531 | } | |
5532 | ||
8de6cae4 | 5533 | void bpf_core_free_cands(struct bpf_core_cand_list *cands) |
ddc7c304 | 5534 | { |
8de6cae4 MV |
5535 | if (!cands) |
5536 | return; | |
5537 | ||
0f7515ca AN |
5538 | free(cands->cands); |
5539 | free(cands); | |
ddc7c304 AN |
5540 | } |
5541 | ||
8de6cae4 MV |
5542 | int bpf_core_add_cands(struct bpf_core_cand *local_cand, |
5543 | size_t local_essent_len, | |
5544 | const struct btf *targ_btf, | |
5545 | const char *targ_btf_name, | |
5546 | int targ_start_id, | |
5547 | struct bpf_core_cand_list *cands) | |
ddc7c304 | 5548 | { |
301ba4d7 | 5549 | struct bpf_core_cand *new_cands, *cand; |
03d5b991 AN |
5550 | const struct btf_type *t, *local_t; |
5551 | const char *targ_name, *local_name; | |
0f7515ca AN |
5552 | size_t targ_essent_len; |
5553 | int n, i; | |
ddc7c304 | 5554 | |
03d5b991 AN |
5555 | local_t = btf__type_by_id(local_cand->btf, local_cand->id); |
5556 | local_name = btf__str_by_offset(local_cand->btf, local_t->name_off); | |
5557 | ||
6a886de0 HC |
5558 | n = btf__type_cnt(targ_btf); |
5559 | for (i = targ_start_id; i < n; i++) { | |
ddc7c304 | 5560 | t = btf__type_by_id(targ_btf, i); |
23b2a3a8 | 5561 | if (!btf_kind_core_compat(t, local_t)) |
ddc7c304 AN |
5562 | continue; |
5563 | ||
3fc32f40 AN |
5564 | targ_name = btf__name_by_offset(targ_btf, t->name_off); |
5565 | if (str_is_empty(targ_name)) | |
d121e1d3 AN |
5566 | continue; |
5567 | ||
ddc7c304 AN |
5568 | targ_essent_len = bpf_core_essential_name_len(targ_name); |
5569 | if (targ_essent_len != local_essent_len) | |
5570 | continue; | |
5571 | ||
03d5b991 | 5572 | if (strncmp(local_name, targ_name, local_essent_len) != 0) |
0f7515ca AN |
5573 | continue; |
5574 | ||
5575 | pr_debug("CO-RE relocating [%d] %s %s: found target candidate [%d] %s %s in [%s]\n", | |
03d5b991 AN |
5576 | local_cand->id, btf_kind_str(local_t), |
5577 | local_name, i, btf_kind_str(t), targ_name, | |
0f7515ca AN |
5578 | targ_btf_name); |
5579 | new_cands = libbpf_reallocarray(cands->cands, cands->len + 1, | |
5580 | sizeof(*cands->cands)); | |
5581 | if (!new_cands) | |
5582 | return -ENOMEM; | |
5583 | ||
5584 | cand = &new_cands[cands->len]; | |
5585 | cand->btf = targ_btf; | |
0f7515ca AN |
5586 | cand->id = i; |
5587 | ||
5588 | cands->cands = new_cands; | |
5589 | cands->len++; | |
ddc7c304 | 5590 | } |
0f7515ca AN |
5591 | return 0; |
5592 | } | |
5593 | ||
4f33a53d AN |
5594 | static int load_module_btfs(struct bpf_object *obj) |
5595 | { | |
5596 | struct bpf_btf_info info; | |
5597 | struct module_btf *mod_btf; | |
5598 | struct btf *btf; | |
5599 | char name[64]; | |
5600 | __u32 id = 0, len; | |
5601 | int err, fd; | |
5602 | ||
5603 | if (obj->btf_modules_loaded) | |
5604 | return 0; | |
5605 | ||
67234743 AS |
5606 | if (obj->gen_loader) |
5607 | return 0; | |
5608 | ||
4f33a53d AN |
5609 | /* don't do this again, even if we find no module BTFs */ |
5610 | obj->btf_modules_loaded = true; | |
5611 | ||
5612 | /* kernel too old to support module BTFs */ | |
9ca1f56a | 5613 | if (!kernel_supports(obj, FEAT_MODULE_BTF)) |
4f33a53d AN |
5614 | return 0; |
5615 | ||
5616 | while (true) { | |
5617 | err = bpf_btf_get_next_id(id, &id); | |
5618 | if (err && errno == ENOENT) | |
5619 | return 0; | |
2d2c9516 AT |
5620 | if (err && errno == EPERM) { |
5621 | pr_debug("skipping module BTFs loading, missing privileges\n"); | |
5622 | return 0; | |
5623 | } | |
4f33a53d AN |
5624 | if (err) { |
5625 | err = -errno; | |
5626 | pr_warn("failed to iterate BTF objects: %d\n", err); | |
5627 | return err; | |
ddc7c304 | 5628 | } |
4f33a53d AN |
5629 | |
5630 | fd = bpf_btf_get_fd_by_id(id); | |
5631 | if (fd < 0) { | |
5632 | if (errno == ENOENT) | |
5633 | continue; /* expected race: BTF was unloaded */ | |
5634 | err = -errno; | |
5635 | pr_warn("failed to get BTF object #%d FD: %d\n", id, err); | |
5636 | return err; | |
5637 | } | |
5638 | ||
5639 | len = sizeof(info); | |
5640 | memset(&info, 0, sizeof(info)); | |
5641 | info.name = ptr_to_u64(name); | |
5642 | info.name_len = sizeof(name); | |
5643 | ||
629dfc66 | 5644 | err = bpf_btf_get_info_by_fd(fd, &info, &len); |
4f33a53d AN |
5645 | if (err) { |
5646 | err = -errno; | |
5647 | pr_warn("failed to get BTF object #%d info: %d\n", id, err); | |
91abb4a6 | 5648 | goto err_out; |
4f33a53d AN |
5649 | } |
5650 | ||
5651 | /* ignore non-module BTFs */ | |
5652 | if (!info.kernel_btf || strcmp(name, "vmlinux") == 0) { | |
5653 | close(fd); | |
5654 | continue; | |
5655 | } | |
5656 | ||
5657 | btf = btf_get_from_fd(fd, obj->btf_vmlinux); | |
e9fc3ce9 AN |
5658 | err = libbpf_get_error(btf); |
5659 | if (err) { | |
5660 | pr_warn("failed to load module [%s]'s BTF object #%d: %d\n", | |
5661 | name, id, err); | |
91abb4a6 | 5662 | goto err_out; |
4f33a53d AN |
5663 | } |
5664 | ||
3b029e06 | 5665 | err = libbpf_ensure_mem((void **)&obj->btf_modules, &obj->btf_module_cap, |
e3ba8e4e | 5666 | sizeof(*obj->btf_modules), obj->btf_module_cnt + 1); |
4f33a53d | 5667 | if (err) |
91abb4a6 | 5668 | goto err_out; |
4f33a53d AN |
5669 | |
5670 | mod_btf = &obj->btf_modules[obj->btf_module_cnt++]; | |
5671 | ||
5672 | mod_btf->btf = btf; | |
5673 | mod_btf->id = id; | |
91abb4a6 | 5674 | mod_btf->fd = fd; |
4f33a53d | 5675 | mod_btf->name = strdup(name); |
91abb4a6 AN |
5676 | if (!mod_btf->name) { |
5677 | err = -ENOMEM; | |
5678 | goto err_out; | |
5679 | } | |
5680 | continue; | |
5681 | ||
5682 | err_out: | |
5683 | close(fd); | |
5684 | return err; | |
ddc7c304 | 5685 | } |
4f33a53d AN |
5686 | |
5687 | return 0; | |
5688 | } | |
5689 | ||
301ba4d7 | 5690 | static struct bpf_core_cand_list * |
0f7515ca AN |
5691 | bpf_core_find_cands(struct bpf_object *obj, const struct btf *local_btf, __u32 local_type_id) |
5692 | { | |
301ba4d7 AS |
5693 | struct bpf_core_cand local_cand = {}; |
5694 | struct bpf_core_cand_list *cands; | |
4f33a53d | 5695 | const struct btf *main_btf; |
03d5b991 AN |
5696 | const struct btf_type *local_t; |
5697 | const char *local_name; | |
0f7515ca | 5698 | size_t local_essent_len; |
4f33a53d | 5699 | int err, i; |
0f7515ca AN |
5700 | |
5701 | local_cand.btf = local_btf; | |
03d5b991 AN |
5702 | local_cand.id = local_type_id; |
5703 | local_t = btf__type_by_id(local_btf, local_type_id); | |
5704 | if (!local_t) | |
0f7515ca AN |
5705 | return ERR_PTR(-EINVAL); |
5706 | ||
03d5b991 AN |
5707 | local_name = btf__name_by_offset(local_btf, local_t->name_off); |
5708 | if (str_is_empty(local_name)) | |
0f7515ca | 5709 | return ERR_PTR(-EINVAL); |
03d5b991 | 5710 | local_essent_len = bpf_core_essential_name_len(local_name); |
0f7515ca AN |
5711 | |
5712 | cands = calloc(1, sizeof(*cands)); | |
5713 | if (!cands) | |
5714 | return ERR_PTR(-ENOMEM); | |
5715 | ||
5716 | /* Attempt to find target candidates in vmlinux BTF first */ | |
4f33a53d AN |
5717 | main_btf = obj->btf_vmlinux_override ?: obj->btf_vmlinux; |
5718 | err = bpf_core_add_cands(&local_cand, local_essent_len, main_btf, "vmlinux", 1, cands); | |
5719 | if (err) | |
5720 | goto err_out; | |
5721 | ||
5722 | /* if vmlinux BTF has any candidate, don't got for module BTFs */ | |
5723 | if (cands->len) | |
5724 | return cands; | |
5725 | ||
5726 | /* if vmlinux BTF was overridden, don't attempt to load module BTFs */ | |
5727 | if (obj->btf_vmlinux_override) | |
5728 | return cands; | |
5729 | ||
5730 | /* now look through module BTFs, trying to still find candidates */ | |
5731 | err = load_module_btfs(obj); | |
5732 | if (err) | |
5733 | goto err_out; | |
5734 | ||
5735 | for (i = 0; i < obj->btf_module_cnt; i++) { | |
5736 | err = bpf_core_add_cands(&local_cand, local_essent_len, | |
5737 | obj->btf_modules[i].btf, | |
5738 | obj->btf_modules[i].name, | |
6a886de0 | 5739 | btf__type_cnt(obj->btf_vmlinux), |
4f33a53d AN |
5740 | cands); |
5741 | if (err) | |
5742 | goto err_out; | |
0f7515ca AN |
5743 | } |
5744 | ||
5745 | return cands; | |
ddc7c304 | 5746 | err_out: |
4f33a53d | 5747 | bpf_core_free_cands(cands); |
ddc7c304 AN |
5748 | return ERR_PTR(err); |
5749 | } | |
5750 | ||
3fc32f40 AN |
5751 | /* Check local and target types for compatibility. This check is used for |
5752 | * type-based CO-RE relocations and follow slightly different rules than | |
5753 | * field-based relocations. This function assumes that root types were already | |
5754 | * checked for name match. Beyond that initial root-level name check, names | |
5755 | * are completely ignored. Compatibility rules are as follows: | |
5756 | * - any two STRUCTs/UNIONs/FWDs/ENUMs/INTs are considered compatible, but | |
5757 | * kind should match for local and target types (i.e., STRUCT is not | |
5758 | * compatible with UNION); | |
5759 | * - for ENUMs, the size is ignored; | |
5760 | * - for INT, size and signedness are ignored; | |
5761 | * - for ARRAY, dimensionality is ignored, element types are checked for | |
5762 | * compatibility recursively; | |
5763 | * - CONST/VOLATILE/RESTRICT modifiers are ignored; | |
5764 | * - TYPEDEFs/PTRs are compatible if types they pointing to are compatible; | |
5765 | * - FUNC_PROTOs are compatible if they have compatible signature: same | |
5766 | * number of input args and compatible return and argument types. | |
5767 | * These rules are not set in stone and probably will be adjusted as we get | |
5768 | * more experience with using BPF CO-RE relocations. | |
5769 | */ | |
b0588390 AS |
5770 | int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id, |
5771 | const struct btf *targ_btf, __u32 targ_id) | |
3fc32f40 | 5772 | { |
fd75733d | 5773 | return __bpf_core_types_are_compat(local_btf, local_id, targ_btf, targ_id, 32); |
3fc32f40 AN |
5774 | } |
5775 | ||
ec6209c8 DM |
5776 | int bpf_core_types_match(const struct btf *local_btf, __u32 local_id, |
5777 | const struct btf *targ_btf, __u32 targ_id) | |
5778 | { | |
5779 | return __bpf_core_types_match(local_btf, local_id, targ_btf, targ_id, false, 32); | |
5780 | } | |
5781 | ||
c302378b | 5782 | static size_t bpf_core_hash_fn(const long key, void *ctx) |
ddc7c304 | 5783 | { |
c302378b | 5784 | return key; |
ddc7c304 AN |
5785 | } |
5786 | ||
c302378b | 5787 | static bool bpf_core_equal_fn(const long k1, const long k2, void *ctx) |
ddc7c304 AN |
5788 | { |
5789 | return k1 == k2; | |
5790 | } | |
5791 | ||
d0e92887 AS |
5792 | static int record_relo_core(struct bpf_program *prog, |
5793 | const struct bpf_core_relo *core_relo, int insn_idx) | |
5794 | { | |
5795 | struct reloc_desc *relos, *relo; | |
5796 | ||
5797 | relos = libbpf_reallocarray(prog->reloc_desc, | |
5798 | prog->nr_reloc + 1, sizeof(*relos)); | |
5799 | if (!relos) | |
5800 | return -ENOMEM; | |
5801 | relo = &relos[prog->nr_reloc]; | |
5802 | relo->type = RELO_CORE; | |
5803 | relo->insn_idx = insn_idx; | |
5804 | relo->core_relo = core_relo; | |
5805 | prog->reloc_desc = relos; | |
5806 | prog->nr_reloc++; | |
5807 | return 0; | |
5808 | } | |
5809 | ||
9fdc4273 AN |
5810 | static const struct bpf_core_relo *find_relo_core(struct bpf_program *prog, int insn_idx) |
5811 | { | |
5812 | struct reloc_desc *relo; | |
5813 | int i; | |
5814 | ||
5815 | for (i = 0; i < prog->nr_reloc; i++) { | |
5816 | relo = &prog->reloc_desc[i]; | |
5817 | if (relo->type != RELO_CORE || relo->insn_idx != insn_idx) | |
5818 | continue; | |
5819 | ||
5820 | return relo->core_relo; | |
5821 | } | |
5822 | ||
5823 | return NULL; | |
5824 | } | |
5825 | ||
adb8fa19 MV |
5826 | static int bpf_core_resolve_relo(struct bpf_program *prog, |
5827 | const struct bpf_core_relo *relo, | |
5828 | int relo_idx, | |
5829 | const struct btf *local_btf, | |
5830 | struct hashmap *cand_cache, | |
5831 | struct bpf_core_relo_res *targ_res) | |
3ee4f533 | 5832 | { |
78c1f8d0 | 5833 | struct bpf_core_spec specs_scratch[3] = {}; |
301ba4d7 | 5834 | struct bpf_core_cand_list *cands = NULL; |
3ee4f533 AS |
5835 | const char *prog_name = prog->name; |
5836 | const struct btf_type *local_type; | |
5837 | const char *local_name; | |
5838 | __u32 local_id = relo->type_id; | |
adb8fa19 | 5839 | int err; |
3ee4f533 AS |
5840 | |
5841 | local_type = btf__type_by_id(local_btf, local_id); | |
5842 | if (!local_type) | |
5843 | return -EINVAL; | |
5844 | ||
5845 | local_name = btf__name_by_offset(local_btf, local_type->name_off); | |
5846 | if (!local_name) | |
5847 | return -EINVAL; | |
5848 | ||
46334a0c | 5849 | if (relo->kind != BPF_CORE_TYPE_ID_LOCAL && |
c302378b | 5850 | !hashmap__find(cand_cache, local_id, &cands)) { |
3ee4f533 AS |
5851 | cands = bpf_core_find_cands(prog->obj, local_btf, local_id); |
5852 | if (IS_ERR(cands)) { | |
5853 | pr_warn("prog '%s': relo #%d: target candidate search failed for [%d] %s %s: %ld\n", | |
5854 | prog_name, relo_idx, local_id, btf_kind_str(local_type), | |
5855 | local_name, PTR_ERR(cands)); | |
5856 | return PTR_ERR(cands); | |
5857 | } | |
c302378b | 5858 | err = hashmap__set(cand_cache, local_id, cands, NULL, NULL); |
3ee4f533 AS |
5859 | if (err) { |
5860 | bpf_core_free_cands(cands); | |
5861 | return err; | |
5862 | } | |
5863 | } | |
5864 | ||
adb8fa19 MV |
5865 | return bpf_core_calc_relo_insn(prog_name, relo, relo_idx, local_btf, cands, specs_scratch, |
5866 | targ_res); | |
3ee4f533 AS |
5867 | } |
5868 | ||
ddc7c304 | 5869 | static int |
28b93c64 | 5870 | bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path) |
ddc7c304 AN |
5871 | { |
5872 | const struct btf_ext_info_sec *sec; | |
adb8fa19 | 5873 | struct bpf_core_relo_res targ_res; |
28b93c64 | 5874 | const struct bpf_core_relo *rec; |
ddc7c304 AN |
5875 | const struct btf_ext_info *seg; |
5876 | struct hashmap_entry *entry; | |
5877 | struct hashmap *cand_cache = NULL; | |
5878 | struct bpf_program *prog; | |
adb8fa19 | 5879 | struct bpf_insn *insn; |
ddc7c304 | 5880 | const char *sec_name; |
11d5daa8 | 5881 | int i, err = 0, insn_idx, sec_idx, sec_num; |
ddc7c304 | 5882 | |
28b93c64 AN |
5883 | if (obj->btf_ext->core_relo_info.len == 0) |
5884 | return 0; | |
5885 | ||
0f7515ca AN |
5886 | if (targ_btf_path) { |
5887 | obj->btf_vmlinux_override = btf__parse(targ_btf_path, NULL); | |
e9fc3ce9 AN |
5888 | err = libbpf_get_error(obj->btf_vmlinux_override); |
5889 | if (err) { | |
0f7515ca AN |
5890 | pr_warn("failed to parse target BTF: %d\n", err); |
5891 | return err; | |
5892 | } | |
ddc7c304 AN |
5893 | } |
5894 | ||
5895 | cand_cache = hashmap__new(bpf_core_hash_fn, bpf_core_equal_fn, NULL); | |
5896 | if (IS_ERR(cand_cache)) { | |
5897 | err = PTR_ERR(cand_cache); | |
5898 | goto out; | |
5899 | } | |
5900 | ||
28b93c64 | 5901 | seg = &obj->btf_ext->core_relo_info; |
11d5daa8 | 5902 | sec_num = 0; |
ddc7c304 | 5903 | for_each_btf_ext_sec(seg, sec) { |
11d5daa8 AN |
5904 | sec_idx = seg->sec_idxs[sec_num]; |
5905 | sec_num++; | |
5906 | ||
ddc7c304 AN |
5907 | sec_name = btf__name_by_offset(obj->btf, sec->sec_name_off); |
5908 | if (str_is_empty(sec_name)) { | |
5909 | err = -EINVAL; | |
5910 | goto out; | |
5911 | } | |
ddc7c304 | 5912 | |
11d5daa8 | 5913 | pr_debug("sec '%s': found %d CO-RE relocations\n", sec_name, sec->num_info); |
ddc7c304 AN |
5914 | |
5915 | for_each_btf_ext_rec(seg, sec, i, rec) { | |
adb8fa19 MV |
5916 | if (rec->insn_off % BPF_INSN_SZ) |
5917 | return -EINVAL; | |
db2b8b06 AN |
5918 | insn_idx = rec->insn_off / BPF_INSN_SZ; |
5919 | prog = find_prog_by_sec_insn(obj, sec_idx, insn_idx); | |
5920 | if (!prog) { | |
e89d57d9 AN |
5921 | /* When __weak subprog is "overridden" by another instance |
5922 | * of the subprog from a different object file, linker still | |
5923 | * appends all the .BTF.ext info that used to belong to that | |
5924 | * eliminated subprogram. | |
5925 | * This is similar to what x86-64 linker does for relocations. | |
5926 | * So just ignore such relocations just like we ignore | |
5927 | * subprog instructions when discovering subprograms. | |
5928 | */ | |
5929 | pr_debug("sec '%s': skipping CO-RE relocation #%d for insn #%d belonging to eliminated weak subprogram\n", | |
5930 | sec_name, i, insn_idx); | |
5931 | continue; | |
db2b8b06 | 5932 | } |
47f7cf63 AN |
5933 | /* no need to apply CO-RE relocation if the program is |
5934 | * not going to be loaded | |
5935 | */ | |
a3820c48 | 5936 | if (!prog->autoload) |
47f7cf63 | 5937 | continue; |
db2b8b06 | 5938 | |
adb8fa19 MV |
5939 | /* adjust insn_idx from section frame of reference to the local |
5940 | * program's frame of reference; (sub-)program code is not yet | |
5941 | * relocated, so it's enough to just subtract in-section offset | |
5942 | */ | |
5943 | insn_idx = insn_idx - prog->sec_insn_off; | |
5944 | if (insn_idx >= prog->insns_cnt) | |
5945 | return -EINVAL; | |
5946 | insn = &prog->insns[insn_idx]; | |
5947 | ||
185cfe83 AN |
5948 | err = record_relo_core(prog, rec, insn_idx); |
5949 | if (err) { | |
5950 | pr_warn("prog '%s': relo #%d: failed to record relocation: %d\n", | |
5951 | prog->name, i, err); | |
5952 | goto out; | |
adb8fa19 MV |
5953 | } |
5954 | ||
185cfe83 AN |
5955 | if (prog->obj->gen_loader) |
5956 | continue; | |
5957 | ||
adb8fa19 | 5958 | err = bpf_core_resolve_relo(prog, rec, i, obj->btf, cand_cache, &targ_res); |
ddc7c304 | 5959 | if (err) { |
be18010e | 5960 | pr_warn("prog '%s': relo #%d: failed to relocate: %d\n", |
9c0f8cbd | 5961 | prog->name, i, err); |
ddc7c304 AN |
5962 | goto out; |
5963 | } | |
adb8fa19 MV |
5964 | |
5965 | err = bpf_core_patch_insn(prog->name, insn, insn_idx, rec, i, &targ_res); | |
5966 | if (err) { | |
5967 | pr_warn("prog '%s': relo #%d: failed to patch insn #%u: %d\n", | |
5968 | prog->name, i, insn_idx, err); | |
5969 | goto out; | |
5970 | } | |
ddc7c304 AN |
5971 | } |
5972 | } | |
5973 | ||
5974 | out: | |
4f33a53d | 5975 | /* obj->btf_vmlinux and module BTFs are freed after object load */ |
0f7515ca AN |
5976 | btf__free(obj->btf_vmlinux_override); |
5977 | obj->btf_vmlinux_override = NULL; | |
5978 | ||
ddc7c304 AN |
5979 | if (!IS_ERR_OR_NULL(cand_cache)) { |
5980 | hashmap__for_each_entry(cand_cache, entry, i) { | |
c302378b | 5981 | bpf_core_free_cands(entry->pvalue); |
ddc7c304 AN |
5982 | } |
5983 | hashmap__free(cand_cache); | |
5984 | } | |
5985 | return err; | |
5986 | } | |
5987 | ||
ec41817b | 5988 | /* base map load ldimm64 special constant, used also for log fixup logic */ |
3055ddd6 AN |
5989 | #define POISON_LDIMM64_MAP_BASE 2001000000 |
5990 | #define POISON_LDIMM64_MAP_PFX "200100" | |
ec41817b AN |
5991 | |
5992 | static void poison_map_ldimm64(struct bpf_program *prog, int relo_idx, | |
5993 | int insn_idx, struct bpf_insn *insn, | |
5994 | int map_idx, const struct bpf_map *map) | |
5995 | { | |
5996 | int i; | |
5997 | ||
5998 | pr_debug("prog '%s': relo #%d: poisoning insn #%d that loads map #%d '%s'\n", | |
5999 | prog->name, relo_idx, insn_idx, map_idx, map->name); | |
6000 | ||
6001 | /* we turn single ldimm64 into two identical invalid calls */ | |
6002 | for (i = 0; i < 2; i++) { | |
6003 | insn->code = BPF_JMP | BPF_CALL; | |
6004 | insn->dst_reg = 0; | |
6005 | insn->src_reg = 0; | |
6006 | insn->off = 0; | |
6007 | /* if this instruction is reachable (not a dead code), | |
6008 | * verifier will complain with something like: | |
6009 | * invalid func unknown#2001000123 | |
6010 | * where lower 123 is map index into obj->maps[] array | |
6011 | */ | |
3055ddd6 | 6012 | insn->imm = POISON_LDIMM64_MAP_BASE + map_idx; |
ec41817b AN |
6013 | |
6014 | insn++; | |
6015 | } | |
6016 | } | |
6017 | ||
05b6f766 AN |
6018 | /* unresolved kfunc call special constant, used also for log fixup logic */ |
6019 | #define POISON_CALL_KFUNC_BASE 2002000000 | |
6020 | #define POISON_CALL_KFUNC_PFX "2002" | |
6021 | ||
6022 | static void poison_kfunc_call(struct bpf_program *prog, int relo_idx, | |
6023 | int insn_idx, struct bpf_insn *insn, | |
6024 | int ext_idx, const struct extern_desc *ext) | |
6025 | { | |
6026 | pr_debug("prog '%s': relo #%d: poisoning insn #%d that calls kfunc '%s'\n", | |
6027 | prog->name, relo_idx, insn_idx, ext->name); | |
6028 | ||
6029 | /* we turn kfunc call into invalid helper call with identifiable constant */ | |
6030 | insn->code = BPF_JMP | BPF_CALL; | |
6031 | insn->dst_reg = 0; | |
6032 | insn->src_reg = 0; | |
6033 | insn->off = 0; | |
6034 | /* if this instruction is reachable (not a dead code), | |
6035 | * verifier will complain with something like: | |
6036 | * invalid func unknown#2001000123 | |
6037 | * where lower 123 is extern index into obj->externs[] array | |
6038 | */ | |
6039 | insn->imm = POISON_CALL_KFUNC_BASE + ext_idx; | |
6040 | } | |
6041 | ||
c3c55696 AN |
6042 | /* Relocate data references within program code: |
6043 | * - map references; | |
6044 | * - global variable references; | |
6045 | * - extern references. | |
6046 | */ | |
48cca7e4 | 6047 | static int |
c3c55696 | 6048 | bpf_object__relocate_data(struct bpf_object *obj, struct bpf_program *prog) |
8a47a6c5 | 6049 | { |
c3c55696 | 6050 | int i; |
8a47a6c5 WN |
6051 | |
6052 | for (i = 0; i < prog->nr_reloc; i++) { | |
53f8dd43 | 6053 | struct reloc_desc *relo = &prog->reloc_desc[i]; |
166750bc | 6054 | struct bpf_insn *insn = &prog->insns[relo->insn_idx]; |
ec41817b | 6055 | const struct bpf_map *map; |
2e33efe3 | 6056 | struct extern_desc *ext; |
8a47a6c5 | 6057 | |
166750bc AN |
6058 | switch (relo->type) { |
6059 | case RELO_LD64: | |
ec41817b | 6060 | map = &obj->maps[relo->map_idx]; |
e2fa0156 AS |
6061 | if (obj->gen_loader) { |
6062 | insn[0].src_reg = BPF_PSEUDO_MAP_IDX; | |
6063 | insn[0].imm = relo->map_idx; | |
ec41817b | 6064 | } else if (map->autocreate) { |
e2fa0156 | 6065 | insn[0].src_reg = BPF_PSEUDO_MAP_FD; |
ec41817b AN |
6066 | insn[0].imm = map->fd; |
6067 | } else { | |
6068 | poison_map_ldimm64(prog, i, relo->insn_idx, insn, | |
6069 | relo->map_idx, map); | |
e2fa0156 | 6070 | } |
166750bc AN |
6071 | break; |
6072 | case RELO_DATA: | |
ec41817b | 6073 | map = &obj->maps[relo->map_idx]; |
166750bc | 6074 | insn[1].imm = insn[0].imm + relo->sym_off; |
e2fa0156 AS |
6075 | if (obj->gen_loader) { |
6076 | insn[0].src_reg = BPF_PSEUDO_MAP_IDX_VALUE; | |
6077 | insn[0].imm = relo->map_idx; | |
ec41817b | 6078 | } else if (map->autocreate) { |
e2fa0156 | 6079 | insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; |
ec41817b AN |
6080 | insn[0].imm = map->fd; |
6081 | } else { | |
6082 | poison_map_ldimm64(prog, i, relo->insn_idx, insn, | |
6083 | relo->map_idx, map); | |
e2fa0156 | 6084 | } |
166750bc | 6085 | break; |
a18f7214 | 6086 | case RELO_EXTERN_LD64: |
3055ddd6 | 6087 | ext = &obj->externs[relo->ext_idx]; |
1c0c7074 | 6088 | if (ext->type == EXT_KCFG) { |
e2fa0156 AS |
6089 | if (obj->gen_loader) { |
6090 | insn[0].src_reg = BPF_PSEUDO_MAP_IDX_VALUE; | |
6091 | insn[0].imm = obj->kconfig_map_idx; | |
6092 | } else { | |
6093 | insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; | |
6094 | insn[0].imm = obj->maps[obj->kconfig_map_idx].fd; | |
6095 | } | |
1c0c7074 AN |
6096 | insn[1].imm = ext->kcfg.data_off; |
6097 | } else /* EXT_KSYM */ { | |
2211c825 | 6098 | if (ext->ksym.type_id && ext->is_set) { /* typed ksyms */ |
d370bbe1 | 6099 | insn[0].src_reg = BPF_PSEUDO_BTF_ID; |
284d2587 AN |
6100 | insn[0].imm = ext->ksym.kernel_btf_id; |
6101 | insn[1].imm = ext->ksym.kernel_btf_obj_fd; | |
2211c825 | 6102 | } else { /* typeless ksyms or unresolved typed ksyms */ |
d370bbe1 HL |
6103 | insn[0].imm = (__u32)ext->ksym.addr; |
6104 | insn[1].imm = ext->ksym.addr >> 32; | |
6105 | } | |
1c0c7074 | 6106 | } |
166750bc | 6107 | break; |
a18f7214 | 6108 | case RELO_EXTERN_CALL: |
3055ddd6 | 6109 | ext = &obj->externs[relo->ext_idx]; |
5bd022ec | 6110 | insn[0].src_reg = BPF_PSEUDO_KFUNC_CALL; |
466b2e13 KKD |
6111 | if (ext->is_set) { |
6112 | insn[0].imm = ext->ksym.kernel_btf_id; | |
6113 | insn[0].off = ext->ksym.btf_fd_idx; | |
05b6f766 AN |
6114 | } else { /* unresolved weak kfunc call */ |
6115 | poison_kfunc_call(prog, i, relo->insn_idx, insn, | |
6116 | relo->ext_idx, ext); | |
466b2e13 | 6117 | } |
5bd022ec | 6118 | break; |
53eddb5e | 6119 | case RELO_SUBPROG_ADDR: |
b1268826 AS |
6120 | if (insn[0].src_reg != BPF_PSEUDO_FUNC) { |
6121 | pr_warn("prog '%s': relo #%d: bad insn\n", | |
6122 | prog->name, i); | |
6123 | return -EINVAL; | |
6124 | } | |
6125 | /* handled already */ | |
53eddb5e | 6126 | break; |
166750bc | 6127 | case RELO_CALL: |
b1268826 | 6128 | /* handled already */ |
166750bc | 6129 | break; |
d0e92887 AS |
6130 | case RELO_CORE: |
6131 | /* will be handled by bpf_program_record_relos() */ | |
6132 | break; | |
166750bc | 6133 | default: |
9c0f8cbd AN |
6134 | pr_warn("prog '%s': relo #%d: bad relo type %d\n", |
6135 | prog->name, i, relo->type); | |
166750bc | 6136 | return -EINVAL; |
8a47a6c5 | 6137 | } |
8a47a6c5 WN |
6138 | } |
6139 | ||
c3c55696 AN |
6140 | return 0; |
6141 | } | |
6142 | ||
8505e870 AN |
6143 | static int adjust_prog_btf_ext_info(const struct bpf_object *obj, |
6144 | const struct bpf_program *prog, | |
6145 | const struct btf_ext_info *ext_info, | |
6146 | void **prog_info, __u32 *prog_rec_cnt, | |
6147 | __u32 *prog_rec_sz) | |
6148 | { | |
6149 | void *copy_start = NULL, *copy_end = NULL; | |
6150 | void *rec, *rec_end, *new_prog_info; | |
6151 | const struct btf_ext_info_sec *sec; | |
6152 | size_t old_sz, new_sz; | |
11d5daa8 | 6153 | int i, sec_num, sec_idx, off_adj; |
8505e870 | 6154 | |
11d5daa8 | 6155 | sec_num = 0; |
8505e870 | 6156 | for_each_btf_ext_sec(ext_info, sec) { |
11d5daa8 AN |
6157 | sec_idx = ext_info->sec_idxs[sec_num]; |
6158 | sec_num++; | |
6159 | if (prog->sec_idx != sec_idx) | |
8505e870 AN |
6160 | continue; |
6161 | ||
6162 | for_each_btf_ext_rec(ext_info, sec, i, rec) { | |
6163 | __u32 insn_off = *(__u32 *)rec / BPF_INSN_SZ; | |
6164 | ||
6165 | if (insn_off < prog->sec_insn_off) | |
6166 | continue; | |
6167 | if (insn_off >= prog->sec_insn_off + prog->sec_insn_cnt) | |
6168 | break; | |
6169 | ||
6170 | if (!copy_start) | |
6171 | copy_start = rec; | |
6172 | copy_end = rec + ext_info->rec_size; | |
6173 | } | |
6174 | ||
6175 | if (!copy_start) | |
6176 | return -ENOENT; | |
6177 | ||
6178 | /* append func/line info of a given (sub-)program to the main | |
6179 | * program func/line info | |
6180 | */ | |
8eb62958 | 6181 | old_sz = (size_t)(*prog_rec_cnt) * ext_info->rec_size; |
8505e870 AN |
6182 | new_sz = old_sz + (copy_end - copy_start); |
6183 | new_prog_info = realloc(*prog_info, new_sz); | |
6184 | if (!new_prog_info) | |
6185 | return -ENOMEM; | |
6186 | *prog_info = new_prog_info; | |
6187 | *prog_rec_cnt = new_sz / ext_info->rec_size; | |
6188 | memcpy(new_prog_info + old_sz, copy_start, copy_end - copy_start); | |
6189 | ||
6190 | /* Kernel instruction offsets are in units of 8-byte | |
6191 | * instructions, while .BTF.ext instruction offsets generated | |
6192 | * by Clang are in units of bytes. So convert Clang offsets | |
6193 | * into kernel offsets and adjust offset according to program | |
6194 | * relocated position. | |
6195 | */ | |
6196 | off_adj = prog->sub_insn_off - prog->sec_insn_off; | |
6197 | rec = new_prog_info + old_sz; | |
6198 | rec_end = new_prog_info + new_sz; | |
6199 | for (; rec < rec_end; rec += ext_info->rec_size) { | |
6200 | __u32 *insn_off = rec; | |
6201 | ||
6202 | *insn_off = *insn_off / BPF_INSN_SZ + off_adj; | |
6203 | } | |
6204 | *prog_rec_sz = ext_info->rec_size; | |
6205 | return 0; | |
6206 | } | |
6207 | ||
6208 | return -ENOENT; | |
6209 | } | |
6210 | ||
6211 | static int | |
6212 | reloc_prog_func_and_line_info(const struct bpf_object *obj, | |
6213 | struct bpf_program *main_prog, | |
6214 | const struct bpf_program *prog) | |
6215 | { | |
6216 | int err; | |
6217 | ||
6218 | /* no .BTF.ext relocation if .BTF.ext is missing or kernel doesn't | |
6219 | * supprot func/line info | |
6220 | */ | |
9ca1f56a | 6221 | if (!obj->btf_ext || !kernel_supports(obj, FEAT_BTF_FUNC)) |
8505e870 AN |
6222 | return 0; |
6223 | ||
6224 | /* only attempt func info relocation if main program's func_info | |
6225 | * relocation was successful | |
6226 | */ | |
6227 | if (main_prog != prog && !main_prog->func_info) | |
6228 | goto line_info; | |
6229 | ||
6230 | err = adjust_prog_btf_ext_info(obj, prog, &obj->btf_ext->func_info, | |
6231 | &main_prog->func_info, | |
6232 | &main_prog->func_info_cnt, | |
6233 | &main_prog->func_info_rec_size); | |
6234 | if (err) { | |
6235 | if (err != -ENOENT) { | |
6236 | pr_warn("prog '%s': error relocating .BTF.ext function info: %d\n", | |
6237 | prog->name, err); | |
6238 | return err; | |
6239 | } | |
6240 | if (main_prog->func_info) { | |
6241 | /* | |
6242 | * Some info has already been found but has problem | |
6243 | * in the last btf_ext reloc. Must have to error out. | |
6244 | */ | |
6245 | pr_warn("prog '%s': missing .BTF.ext function info.\n", prog->name); | |
6246 | return err; | |
6247 | } | |
6248 | /* Have problem loading the very first info. Ignore the rest. */ | |
6249 | pr_warn("prog '%s': missing .BTF.ext function info for the main program, skipping all of .BTF.ext func info.\n", | |
6250 | prog->name); | |
6251 | } | |
6252 | ||
6253 | line_info: | |
6254 | /* don't relocate line info if main program's relocation failed */ | |
6255 | if (main_prog != prog && !main_prog->line_info) | |
6256 | return 0; | |
6257 | ||
6258 | err = adjust_prog_btf_ext_info(obj, prog, &obj->btf_ext->line_info, | |
6259 | &main_prog->line_info, | |
6260 | &main_prog->line_info_cnt, | |
6261 | &main_prog->line_info_rec_size); | |
6262 | if (err) { | |
6263 | if (err != -ENOENT) { | |
6264 | pr_warn("prog '%s': error relocating .BTF.ext line info: %d\n", | |
6265 | prog->name, err); | |
6266 | return err; | |
6267 | } | |
6268 | if (main_prog->line_info) { | |
6269 | /* | |
6270 | * Some info has already been found but has problem | |
6271 | * in the last btf_ext reloc. Must have to error out. | |
6272 | */ | |
6273 | pr_warn("prog '%s': missing .BTF.ext line info.\n", prog->name); | |
6274 | return err; | |
6275 | } | |
6276 | /* Have problem loading the very first info. Ignore the rest. */ | |
6277 | pr_warn("prog '%s': missing .BTF.ext line info for the main program, skipping all of .BTF.ext line info.\n", | |
6278 | prog->name); | |
6279 | } | |
6280 | return 0; | |
6281 | } | |
6282 | ||
c3c55696 AN |
6283 | static int cmp_relo_by_insn_idx(const void *key, const void *elem) |
6284 | { | |
6285 | size_t insn_idx = *(const size_t *)key; | |
6286 | const struct reloc_desc *relo = elem; | |
6287 | ||
6288 | if (insn_idx == relo->insn_idx) | |
6289 | return 0; | |
6290 | return insn_idx < relo->insn_idx ? -1 : 1; | |
6291 | } | |
6292 | ||
6293 | static struct reloc_desc *find_prog_insn_relo(const struct bpf_program *prog, size_t insn_idx) | |
6294 | { | |
2a6a9bf2 AN |
6295 | if (!prog->nr_reloc) |
6296 | return NULL; | |
c3c55696 AN |
6297 | return bsearch(&insn_idx, prog->reloc_desc, prog->nr_reloc, |
6298 | sizeof(*prog->reloc_desc), cmp_relo_by_insn_idx); | |
6299 | } | |
6300 | ||
b1268826 AS |
6301 | static int append_subprog_relos(struct bpf_program *main_prog, struct bpf_program *subprog) |
6302 | { | |
6303 | int new_cnt = main_prog->nr_reloc + subprog->nr_reloc; | |
6304 | struct reloc_desc *relos; | |
6305 | int i; | |
6306 | ||
6307 | if (main_prog == subprog) | |
6308 | return 0; | |
6309 | relos = libbpf_reallocarray(main_prog->reloc_desc, new_cnt, sizeof(*relos)); | |
8a0260db AN |
6310 | /* if new count is zero, reallocarray can return a valid NULL result; |
6311 | * in this case the previous pointer will be freed, so we *have to* | |
6312 | * reassign old pointer to the new value (even if it's NULL) | |
6313 | */ | |
6314 | if (!relos && new_cnt) | |
b1268826 | 6315 | return -ENOMEM; |
2a6a9bf2 AN |
6316 | if (subprog->nr_reloc) |
6317 | memcpy(relos + main_prog->nr_reloc, subprog->reloc_desc, | |
6318 | sizeof(*relos) * subprog->nr_reloc); | |
b1268826 AS |
6319 | |
6320 | for (i = main_prog->nr_reloc; i < new_cnt; i++) | |
6321 | relos[i].insn_idx += subprog->sub_insn_off; | |
6322 | /* After insn_idx adjustment the 'relos' array is still sorted | |
6323 | * by insn_idx and doesn't break bsearch. | |
6324 | */ | |
6325 | main_prog->reloc_desc = relos; | |
6326 | main_prog->nr_reloc = new_cnt; | |
6327 | return 0; | |
6328 | } | |
6329 | ||
6c918709 KKD |
6330 | static int |
6331 | bpf_object__append_subprog_code(struct bpf_object *obj, struct bpf_program *main_prog, | |
6332 | struct bpf_program *subprog) | |
6333 | { | |
6334 | struct bpf_insn *insns; | |
6335 | size_t new_cnt; | |
6336 | int err; | |
6337 | ||
6338 | subprog->sub_insn_off = main_prog->insns_cnt; | |
6339 | ||
6340 | new_cnt = main_prog->insns_cnt + subprog->insns_cnt; | |
6341 | insns = libbpf_reallocarray(main_prog->insns, new_cnt, sizeof(*insns)); | |
6342 | if (!insns) { | |
6343 | pr_warn("prog '%s': failed to realloc prog code\n", main_prog->name); | |
6344 | return -ENOMEM; | |
6345 | } | |
6346 | main_prog->insns = insns; | |
6347 | main_prog->insns_cnt = new_cnt; | |
6348 | ||
6349 | memcpy(main_prog->insns + subprog->sub_insn_off, subprog->insns, | |
6350 | subprog->insns_cnt * sizeof(*insns)); | |
6351 | ||
6352 | pr_debug("prog '%s': added %zu insns from sub-prog '%s'\n", | |
6353 | main_prog->name, subprog->insns_cnt, subprog->name); | |
6354 | ||
6355 | /* The subprog insns are now appended. Append its relos too. */ | |
6356 | err = append_subprog_relos(main_prog, subprog); | |
6357 | if (err) | |
6358 | return err; | |
6359 | return 0; | |
6360 | } | |
6361 | ||
c3c55696 AN |
6362 | static int |
6363 | bpf_object__reloc_code(struct bpf_object *obj, struct bpf_program *main_prog, | |
6364 | struct bpf_program *prog) | |
6365 | { | |
7e2925f6 | 6366 | size_t sub_insn_idx, insn_idx; |
c3c55696 | 6367 | struct bpf_program *subprog; |
c3c55696 | 6368 | struct reloc_desc *relo; |
7e2925f6 | 6369 | struct bpf_insn *insn; |
c3c55696 AN |
6370 | int err; |
6371 | ||
6372 | err = reloc_prog_func_and_line_info(obj, main_prog, prog); | |
6373 | if (err) | |
6374 | return err; | |
6375 | ||
6376 | for (insn_idx = 0; insn_idx < prog->sec_insn_cnt; insn_idx++) { | |
6377 | insn = &main_prog->insns[prog->sub_insn_off + insn_idx]; | |
53eddb5e | 6378 | if (!insn_is_subprog_call(insn) && !insn_is_pseudo_func(insn)) |
c3c55696 AN |
6379 | continue; |
6380 | ||
6381 | relo = find_prog_insn_relo(prog, insn_idx); | |
a18f7214 | 6382 | if (relo && relo->type == RELO_EXTERN_CALL) |
b1268826 AS |
6383 | /* kfunc relocations will be handled later |
6384 | * in bpf_object__relocate_data() | |
6385 | */ | |
6386 | continue; | |
53eddb5e | 6387 | if (relo && relo->type != RELO_CALL && relo->type != RELO_SUBPROG_ADDR) { |
c3c55696 AN |
6388 | pr_warn("prog '%s': unexpected relo for insn #%zu, type %d\n", |
6389 | prog->name, insn_idx, relo->type); | |
6390 | return -LIBBPF_ERRNO__RELOC; | |
6391 | } | |
6392 | if (relo) { | |
6393 | /* sub-program instruction index is a combination of | |
6394 | * an offset of a symbol pointed to by relocation and | |
6395 | * call instruction's imm field; for global functions, | |
6396 | * call always has imm = -1, but for static functions | |
6397 | * relocation is against STT_SECTION and insn->imm | |
6398 | * points to a start of a static function | |
53eddb5e YS |
6399 | * |
6400 | * for subprog addr relocation, the relo->sym_off + insn->imm is | |
6401 | * the byte offset in the corresponding section. | |
c3c55696 | 6402 | */ |
53eddb5e YS |
6403 | if (relo->type == RELO_CALL) |
6404 | sub_insn_idx = relo->sym_off / BPF_INSN_SZ + insn->imm + 1; | |
6405 | else | |
6406 | sub_insn_idx = (relo->sym_off + insn->imm) / BPF_INSN_SZ; | |
6407 | } else if (insn_is_pseudo_func(insn)) { | |
6408 | /* | |
6409 | * RELO_SUBPROG_ADDR relo is always emitted even if both | |
6410 | * functions are in the same section, so it shouldn't reach here. | |
6411 | */ | |
6412 | pr_warn("prog '%s': missing subprog addr relo for insn #%zu\n", | |
6413 | prog->name, insn_idx); | |
6414 | return -LIBBPF_ERRNO__RELOC; | |
c3c55696 AN |
6415 | } else { |
6416 | /* if subprogram call is to a static function within | |
6417 | * the same ELF section, there won't be any relocation | |
6418 | * emitted, but it also means there is no additional | |
6419 | * offset necessary, insns->imm is relative to | |
6420 | * instruction's original position within the section | |
6421 | */ | |
6422 | sub_insn_idx = prog->sec_insn_off + insn_idx + insn->imm + 1; | |
6423 | } | |
6424 | ||
6425 | /* we enforce that sub-programs should be in .text section */ | |
6426 | subprog = find_prog_by_sec_insn(obj, obj->efile.text_shndx, sub_insn_idx); | |
6427 | if (!subprog) { | |
6428 | pr_warn("prog '%s': no .text section found yet sub-program call exists\n", | |
6429 | prog->name); | |
6430 | return -LIBBPF_ERRNO__RELOC; | |
6431 | } | |
6432 | ||
6433 | /* if it's the first call instruction calling into this | |
6434 | * subprogram (meaning this subprog hasn't been processed | |
6435 | * yet) within the context of current main program: | |
6436 | * - append it at the end of main program's instructions blog; | |
6437 | * - process is recursively, while current program is put on hold; | |
6438 | * - if that subprogram calls some other not yet processes | |
6439 | * subprogram, same thing will happen recursively until | |
6440 | * there are no more unprocesses subprograms left to append | |
6441 | * and relocate. | |
6442 | */ | |
6443 | if (subprog->sub_insn_off == 0) { | |
6c918709 | 6444 | err = bpf_object__append_subprog_code(obj, main_prog, subprog); |
b1268826 AS |
6445 | if (err) |
6446 | return err; | |
c3c55696 AN |
6447 | err = bpf_object__reloc_code(obj, main_prog, subprog); |
6448 | if (err) | |
6449 | return err; | |
6450 | } | |
6451 | ||
6452 | /* main_prog->insns memory could have been re-allocated, so | |
6453 | * calculate pointer again | |
6454 | */ | |
6455 | insn = &main_prog->insns[prog->sub_insn_off + insn_idx]; | |
6456 | /* calculate correct instruction position within current main | |
6457 | * prog; each main prog can have a different set of | |
6458 | * subprograms appended (potentially in different order as | |
6459 | * well), so position of any subprog can be different for | |
e3ba8e4e KM |
6460 | * different main programs |
6461 | */ | |
c3c55696 AN |
6462 | insn->imm = subprog->sub_insn_off - (prog->sub_insn_off + insn_idx) - 1; |
6463 | ||
c3c55696 AN |
6464 | pr_debug("prog '%s': insn #%zu relocated, imm %d points to subprog '%s' (now at %zu offset)\n", |
6465 | prog->name, insn_idx, insn->imm, subprog->name, subprog->sub_insn_off); | |
6466 | } | |
6467 | ||
6468 | return 0; | |
6469 | } | |
6470 | ||
6471 | /* | |
6472 | * Relocate sub-program calls. | |
6473 | * | |
6474 | * Algorithm operates as follows. Each entry-point BPF program (referred to as | |
6475 | * main prog) is processed separately. For each subprog (non-entry functions, | |
6476 | * that can be called from either entry progs or other subprogs) gets their | |
6477 | * sub_insn_off reset to zero. This serves as indicator that this subprogram | |
6478 | * hasn't been yet appended and relocated within current main prog. Once its | |
6479 | * relocated, sub_insn_off will point at the position within current main prog | |
6480 | * where given subprog was appended. This will further be used to relocate all | |
6481 | * the call instructions jumping into this subprog. | |
6482 | * | |
6483 | * We start with main program and process all call instructions. If the call | |
6484 | * is into a subprog that hasn't been processed (i.e., subprog->sub_insn_off | |
6485 | * is zero), subprog instructions are appended at the end of main program's | |
6486 | * instruction array. Then main program is "put on hold" while we recursively | |
6487 | * process newly appended subprogram. If that subprogram calls into another | |
6488 | * subprogram that hasn't been appended, new subprogram is appended again to | |
6489 | * the *main* prog's instructions (subprog's instructions are always left | |
6490 | * untouched, as they need to be in unmodified state for subsequent main progs | |
6491 | * and subprog instructions are always sent only as part of a main prog) and | |
6492 | * the process continues recursively. Once all the subprogs called from a main | |
6493 | * prog or any of its subprogs are appended (and relocated), all their | |
6494 | * positions within finalized instructions array are known, so it's easy to | |
6495 | * rewrite call instructions with correct relative offsets, corresponding to | |
6496 | * desired target subprog. | |
6497 | * | |
6498 | * Its important to realize that some subprogs might not be called from some | |
6499 | * main prog and any of its called/used subprogs. Those will keep their | |
6500 | * subprog->sub_insn_off as zero at all times and won't be appended to current | |
6501 | * main prog and won't be relocated within the context of current main prog. | |
6502 | * They might still be used from other main progs later. | |
6503 | * | |
6504 | * Visually this process can be shown as below. Suppose we have two main | |
6505 | * programs mainA and mainB and BPF object contains three subprogs: subA, | |
6506 | * subB, and subC. mainA calls only subA, mainB calls only subC, but subA and | |
6507 | * subC both call subB: | |
6508 | * | |
6509 | * +--------+ +-------+ | |
6510 | * | v v | | |
6511 | * +--+---+ +--+-+-+ +---+--+ | |
6512 | * | subA | | subB | | subC | | |
6513 | * +--+---+ +------+ +---+--+ | |
6514 | * ^ ^ | |
6515 | * | | | |
6516 | * +---+-------+ +------+----+ | |
6517 | * | mainA | | mainB | | |
6518 | * +-----------+ +-----------+ | |
6519 | * | |
6520 | * We'll start relocating mainA, will find subA, append it and start | |
6521 | * processing sub A recursively: | |
6522 | * | |
6523 | * +-----------+------+ | |
6524 | * | mainA | subA | | |
6525 | * +-----------+------+ | |
6526 | * | |
6527 | * At this point we notice that subB is used from subA, so we append it and | |
6528 | * relocate (there are no further subcalls from subB): | |
6529 | * | |
6530 | * +-----------+------+------+ | |
6531 | * | mainA | subA | subB | | |
6532 | * +-----------+------+------+ | |
6533 | * | |
6534 | * At this point, we relocate subA calls, then go one level up and finish with | |
6535 | * relocatin mainA calls. mainA is done. | |
6536 | * | |
6537 | * For mainB process is similar but results in different order. We start with | |
6538 | * mainB and skip subA and subB, as mainB never calls them (at least | |
6539 | * directly), but we see subC is needed, so we append and start processing it: | |
6540 | * | |
6541 | * +-----------+------+ | |
6542 | * | mainB | subC | | |
6543 | * +-----------+------+ | |
6544 | * Now we see subC needs subB, so we go back to it, append and relocate it: | |
6545 | * | |
6546 | * +-----------+------+------+ | |
6547 | * | mainB | subC | subB | | |
6548 | * +-----------+------+------+ | |
6549 | * | |
6550 | * At this point we unwind recursion, relocate calls in subC, then in mainB. | |
6551 | */ | |
6552 | static int | |
6553 | bpf_object__relocate_calls(struct bpf_object *obj, struct bpf_program *prog) | |
6554 | { | |
6555 | struct bpf_program *subprog; | |
d3d93e34 | 6556 | int i, err; |
c3c55696 | 6557 | |
c3c55696 AN |
6558 | /* mark all subprogs as not relocated (yet) within the context of |
6559 | * current main program | |
6560 | */ | |
6561 | for (i = 0; i < obj->nr_programs; i++) { | |
6562 | subprog = &obj->programs[i]; | |
6563 | if (!prog_is_subprog(obj, subprog)) | |
6564 | continue; | |
6565 | ||
6566 | subprog->sub_insn_off = 0; | |
c3c55696 AN |
6567 | } |
6568 | ||
6569 | err = bpf_object__reloc_code(obj, prog, prog); | |
6570 | if (err) | |
6571 | return err; | |
6572 | ||
8a47a6c5 WN |
6573 | return 0; |
6574 | } | |
6575 | ||
67234743 AS |
6576 | static void |
6577 | bpf_object__free_relocs(struct bpf_object *obj) | |
6578 | { | |
6579 | struct bpf_program *prog; | |
6580 | int i; | |
6581 | ||
6582 | /* free up relocation descriptors */ | |
6583 | for (i = 0; i < obj->nr_programs; i++) { | |
6584 | prog = &obj->programs[i]; | |
6585 | zfree(&prog->reloc_desc); | |
6586 | prog->nr_reloc = 0; | |
6587 | } | |
6588 | } | |
6589 | ||
d0e92887 AS |
6590 | static int cmp_relocs(const void *_a, const void *_b) |
6591 | { | |
6592 | const struct reloc_desc *a = _a; | |
6593 | const struct reloc_desc *b = _b; | |
6594 | ||
6595 | if (a->insn_idx != b->insn_idx) | |
6596 | return a->insn_idx < b->insn_idx ? -1 : 1; | |
6597 | ||
6598 | /* no two relocations should have the same insn_idx, but ... */ | |
6599 | if (a->type != b->type) | |
6600 | return a->type < b->type ? -1 : 1; | |
6601 | ||
6602 | return 0; | |
6603 | } | |
6604 | ||
6605 | static void bpf_object__sort_relos(struct bpf_object *obj) | |
6606 | { | |
6607 | int i; | |
6608 | ||
6609 | for (i = 0; i < obj->nr_programs; i++) { | |
6610 | struct bpf_program *p = &obj->programs[i]; | |
6611 | ||
6612 | if (!p->nr_reloc) | |
6613 | continue; | |
6614 | ||
6615 | qsort(p->reloc_desc, p->nr_reloc, sizeof(*p->reloc_desc), cmp_relocs); | |
6616 | } | |
6617 | } | |
6618 | ||
8a47a6c5 | 6619 | static int |
ddc7c304 | 6620 | bpf_object__relocate(struct bpf_object *obj, const char *targ_btf_path) |
8a47a6c5 WN |
6621 | { |
6622 | struct bpf_program *prog; | |
b1268826 | 6623 | size_t i, j; |
8a47a6c5 WN |
6624 | int err; |
6625 | ||
ddc7c304 AN |
6626 | if (obj->btf_ext) { |
6627 | err = bpf_object__relocate_core(obj, targ_btf_path); | |
6628 | if (err) { | |
be18010e KW |
6629 | pr_warn("failed to perform CO-RE relocations: %d\n", |
6630 | err); | |
ddc7c304 AN |
6631 | return err; |
6632 | } | |
185cfe83 | 6633 | bpf_object__sort_relos(obj); |
ddc7c304 | 6634 | } |
b1268826 AS |
6635 | |
6636 | /* Before relocating calls pre-process relocations and mark | |
6637 | * few ld_imm64 instructions that points to subprogs. | |
6638 | * Otherwise bpf_object__reloc_code() later would have to consider | |
6639 | * all ld_imm64 insns as relocation candidates. That would | |
6640 | * reduce relocation speed, since amount of find_prog_insn_relo() | |
6641 | * would increase and most of them will fail to find a relo. | |
9173cac3 AN |
6642 | */ |
6643 | for (i = 0; i < obj->nr_programs; i++) { | |
6644 | prog = &obj->programs[i]; | |
b1268826 AS |
6645 | for (j = 0; j < prog->nr_reloc; j++) { |
6646 | struct reloc_desc *relo = &prog->reloc_desc[j]; | |
6647 | struct bpf_insn *insn = &prog->insns[relo->insn_idx]; | |
6648 | ||
6649 | /* mark the insn, so it's recognized by insn_is_pseudo_func() */ | |
6650 | if (relo->type == RELO_SUBPROG_ADDR) | |
6651 | insn[0].src_reg = BPF_PSEUDO_FUNC; | |
9173cac3 | 6652 | } |
9173cac3 | 6653 | } |
b1268826 AS |
6654 | |
6655 | /* relocate subprogram calls and append used subprograms to main | |
c3c55696 AN |
6656 | * programs; each copy of subprogram code needs to be relocated |
6657 | * differently for each main program, because its code location might | |
b1268826 AS |
6658 | * have changed. |
6659 | * Append subprog relos to main programs to allow data relos to be | |
6660 | * processed after text is completely relocated. | |
9173cac3 | 6661 | */ |
8a47a6c5 WN |
6662 | for (i = 0; i < obj->nr_programs; i++) { |
6663 | prog = &obj->programs[i]; | |
c3c55696 AN |
6664 | /* sub-program's sub-calls are relocated within the context of |
6665 | * its main program only | |
6666 | */ | |
6667 | if (prog_is_subprog(obj, prog)) | |
9173cac3 | 6668 | continue; |
a3820c48 | 6669 | if (!prog->autoload) |
16e0c35c | 6670 | continue; |
8a47a6c5 | 6671 | |
c3c55696 | 6672 | err = bpf_object__relocate_calls(obj, prog); |
8a47a6c5 | 6673 | if (err) { |
9c0f8cbd AN |
6674 | pr_warn("prog '%s': failed to relocate calls: %d\n", |
6675 | prog->name, err); | |
8a47a6c5 WN |
6676 | return err; |
6677 | } | |
7e2925f6 KKD |
6678 | |
6679 | /* Now, also append exception callback if it has not been done already. */ | |
6680 | if (prog->exception_cb_idx >= 0) { | |
6681 | struct bpf_program *subprog = &obj->programs[prog->exception_cb_idx]; | |
6682 | ||
6683 | /* Calling exception callback directly is disallowed, which the | |
6684 | * verifier will reject later. In case it was processed already, | |
6685 | * we can skip this step, otherwise for all other valid cases we | |
6686 | * have to append exception callback now. | |
6687 | */ | |
6688 | if (subprog->sub_insn_off == 0) { | |
6689 | err = bpf_object__append_subprog_code(obj, prog, subprog); | |
6690 | if (err) | |
6691 | return err; | |
6692 | err = bpf_object__reloc_code(obj, prog, subprog); | |
6693 | if (err) | |
6694 | return err; | |
6695 | } | |
6696 | } | |
8a47a6c5 | 6697 | } |
b1268826 AS |
6698 | /* Process data relos for main programs */ |
6699 | for (i = 0; i < obj->nr_programs; i++) { | |
6700 | prog = &obj->programs[i]; | |
6701 | if (prog_is_subprog(obj, prog)) | |
6702 | continue; | |
a3820c48 | 6703 | if (!prog->autoload) |
16e0c35c | 6704 | continue; |
b1268826 AS |
6705 | err = bpf_object__relocate_data(obj, prog); |
6706 | if (err) { | |
6707 | pr_warn("prog '%s': failed to relocate data references: %d\n", | |
6708 | prog->name, err); | |
6709 | return err; | |
6710 | } | |
6711 | } | |
185cfe83 | 6712 | |
8a47a6c5 WN |
6713 | return 0; |
6714 | } | |
6715 | ||
646f02ff | 6716 | static int bpf_object__collect_st_ops_relos(struct bpf_object *obj, |
ad23b723 | 6717 | Elf64_Shdr *shdr, Elf_Data *data); |
646f02ff AN |
6718 | |
6719 | static int bpf_object__collect_map_relos(struct bpf_object *obj, | |
ad23b723 | 6720 | Elf64_Shdr *shdr, Elf_Data *data) |
646f02ff | 6721 | { |
15728ad3 AN |
6722 | const int bpf_ptr_sz = 8, host_ptr_sz = sizeof(void *); |
6723 | int i, j, nrels, new_sz; | |
063e6881 | 6724 | const struct btf_var_secinfo *vi = NULL; |
646f02ff | 6725 | const struct btf_type *sec, *var, *def; |
341ac5ff HC |
6726 | struct bpf_map *map = NULL, *targ_map = NULL; |
6727 | struct bpf_program *targ_prog = NULL; | |
6728 | bool is_prog_array, is_map_in_map; | |
646f02ff | 6729 | const struct btf_member *member; |
341ac5ff | 6730 | const char *name, *mname, *type; |
646f02ff | 6731 | unsigned int moff; |
ad23b723 AN |
6732 | Elf64_Sym *sym; |
6733 | Elf64_Rel *rel; | |
646f02ff AN |
6734 | void *tmp; |
6735 | ||
6736 | if (!obj->efile.btf_maps_sec_btf_id || !obj->btf) | |
6737 | return -EINVAL; | |
6738 | sec = btf__type_by_id(obj->btf, obj->efile.btf_maps_sec_btf_id); | |
6739 | if (!sec) | |
6740 | return -EINVAL; | |
6741 | ||
646f02ff AN |
6742 | nrels = shdr->sh_size / shdr->sh_entsize; |
6743 | for (i = 0; i < nrels; i++) { | |
ad23b723 AN |
6744 | rel = elf_rel_by_idx(data, i); |
6745 | if (!rel) { | |
646f02ff AN |
6746 | pr_warn(".maps relo #%d: failed to get ELF relo\n", i); |
6747 | return -LIBBPF_ERRNO__FORMAT; | |
6748 | } | |
ad23b723 AN |
6749 | |
6750 | sym = elf_sym_by_idx(obj, ELF64_R_SYM(rel->r_info)); | |
6751 | if (!sym) { | |
646f02ff | 6752 | pr_warn(".maps relo #%d: symbol %zx not found\n", |
ad23b723 | 6753 | i, (size_t)ELF64_R_SYM(rel->r_info)); |
646f02ff AN |
6754 | return -LIBBPF_ERRNO__FORMAT; |
6755 | } | |
ad23b723 | 6756 | name = elf_sym_str(obj, sym->st_name) ?: "<?>"; |
646f02ff | 6757 | |
ad23b723 AN |
6758 | pr_debug(".maps relo #%d: for %zd value %zd rel->r_offset %zu name %d ('%s')\n", |
6759 | i, (ssize_t)(rel->r_info >> 32), (size_t)sym->st_value, | |
6760 | (size_t)rel->r_offset, sym->st_name, name); | |
646f02ff AN |
6761 | |
6762 | for (j = 0; j < obj->nr_maps; j++) { | |
6763 | map = &obj->maps[j]; | |
6764 | if (map->sec_idx != obj->efile.btf_maps_shndx) | |
6765 | continue; | |
6766 | ||
6767 | vi = btf_var_secinfos(sec) + map->btf_var_idx; | |
ad23b723 AN |
6768 | if (vi->offset <= rel->r_offset && |
6769 | rel->r_offset + bpf_ptr_sz <= vi->offset + vi->size) | |
646f02ff AN |
6770 | break; |
6771 | } | |
6772 | if (j == obj->nr_maps) { | |
ad23b723 AN |
6773 | pr_warn(".maps relo #%d: cannot find map '%s' at rel->r_offset %zu\n", |
6774 | i, name, (size_t)rel->r_offset); | |
646f02ff AN |
6775 | return -EINVAL; |
6776 | } | |
6777 | ||
341ac5ff HC |
6778 | is_map_in_map = bpf_map_type__is_map_in_map(map->def.type); |
6779 | is_prog_array = map->def.type == BPF_MAP_TYPE_PROG_ARRAY; | |
6780 | type = is_map_in_map ? "map" : "prog"; | |
6781 | if (is_map_in_map) { | |
6782 | if (sym->st_shndx != obj->efile.btf_maps_shndx) { | |
6783 | pr_warn(".maps relo #%d: '%s' isn't a BTF-defined map\n", | |
6784 | i, name); | |
6785 | return -LIBBPF_ERRNO__RELOC; | |
6786 | } | |
6787 | if (map->def.type == BPF_MAP_TYPE_HASH_OF_MAPS && | |
6788 | map->def.key_size != sizeof(int)) { | |
6789 | pr_warn(".maps relo #%d: hash-of-maps '%s' should have key size %zu.\n", | |
6790 | i, map->name, sizeof(int)); | |
6791 | return -EINVAL; | |
6792 | } | |
6793 | targ_map = bpf_object__find_map_by_name(obj, name); | |
6794 | if (!targ_map) { | |
6795 | pr_warn(".maps relo #%d: '%s' isn't a valid map reference\n", | |
6796 | i, name); | |
6797 | return -ESRCH; | |
6798 | } | |
6799 | } else if (is_prog_array) { | |
6800 | targ_prog = bpf_object__find_program_by_name(obj, name); | |
6801 | if (!targ_prog) { | |
6802 | pr_warn(".maps relo #%d: '%s' isn't a valid program reference\n", | |
6803 | i, name); | |
6804 | return -ESRCH; | |
6805 | } | |
6806 | if (targ_prog->sec_idx != sym->st_shndx || | |
6807 | targ_prog->sec_insn_off * 8 != sym->st_value || | |
6808 | prog_is_subprog(obj, targ_prog)) { | |
6809 | pr_warn(".maps relo #%d: '%s' isn't an entry-point program\n", | |
6810 | i, name); | |
6811 | return -LIBBPF_ERRNO__RELOC; | |
6812 | } | |
6813 | } else { | |
646f02ff AN |
6814 | return -EINVAL; |
6815 | } | |
6816 | ||
646f02ff AN |
6817 | var = btf__type_by_id(obj->btf, vi->type); |
6818 | def = skip_mods_and_typedefs(obj->btf, var->type, NULL); | |
6819 | if (btf_vlen(def) == 0) | |
6820 | return -EINVAL; | |
6821 | member = btf_members(def) + btf_vlen(def) - 1; | |
6822 | mname = btf__name_by_offset(obj->btf, member->name_off); | |
6823 | if (strcmp(mname, "values")) | |
6824 | return -EINVAL; | |
6825 | ||
6826 | moff = btf_member_bit_offset(def, btf_vlen(def) - 1) / 8; | |
ad23b723 | 6827 | if (rel->r_offset - vi->offset < moff) |
646f02ff AN |
6828 | return -EINVAL; |
6829 | ||
ad23b723 | 6830 | moff = rel->r_offset - vi->offset - moff; |
15728ad3 AN |
6831 | /* here we use BPF pointer size, which is always 64 bit, as we |
6832 | * are parsing ELF that was built for BPF target | |
6833 | */ | |
6834 | if (moff % bpf_ptr_sz) | |
646f02ff | 6835 | return -EINVAL; |
15728ad3 | 6836 | moff /= bpf_ptr_sz; |
646f02ff AN |
6837 | if (moff >= map->init_slots_sz) { |
6838 | new_sz = moff + 1; | |
029258d7 | 6839 | tmp = libbpf_reallocarray(map->init_slots, new_sz, host_ptr_sz); |
646f02ff AN |
6840 | if (!tmp) |
6841 | return -ENOMEM; | |
6842 | map->init_slots = tmp; | |
6843 | memset(map->init_slots + map->init_slots_sz, 0, | |
15728ad3 | 6844 | (new_sz - map->init_slots_sz) * host_ptr_sz); |
646f02ff AN |
6845 | map->init_slots_sz = new_sz; |
6846 | } | |
341ac5ff | 6847 | map->init_slots[moff] = is_map_in_map ? (void *)targ_map : (void *)targ_prog; |
646f02ff | 6848 | |
341ac5ff HC |
6849 | pr_debug(".maps relo #%d: map '%s' slot [%d] points to %s '%s'\n", |
6850 | i, map->name, moff, type, name); | |
646f02ff AN |
6851 | } |
6852 | ||
6853 | return 0; | |
6854 | } | |
590a0088 | 6855 | |
c3c55696 AN |
6856 | static int bpf_object__collect_relos(struct bpf_object *obj) |
6857 | { | |
6858 | int i, err; | |
34090915 | 6859 | |
25bbbd7a AN |
6860 | for (i = 0; i < obj->efile.sec_cnt; i++) { |
6861 | struct elf_sec_desc *sec_desc = &obj->efile.secs[i]; | |
6862 | Elf64_Shdr *shdr; | |
6863 | Elf_Data *data; | |
6864 | int idx; | |
6865 | ||
6866 | if (sec_desc->sec_type != SEC_RELO) | |
6867 | continue; | |
6868 | ||
6869 | shdr = sec_desc->shdr; | |
6870 | data = sec_desc->data; | |
6871 | idx = shdr->sh_info; | |
34090915 WN |
6872 | |
6873 | if (shdr->sh_type != SHT_REL) { | |
be18010e | 6874 | pr_warn("internal error at %d\n", __LINE__); |
6371ca3b | 6875 | return -LIBBPF_ERRNO__INTERNAL; |
34090915 WN |
6876 | } |
6877 | ||
809a69d6 | 6878 | if (idx == obj->efile.st_ops_shndx || idx == obj->efile.st_ops_link_shndx) |
646f02ff | 6879 | err = bpf_object__collect_st_ops_relos(obj, shdr, data); |
c3c55696 | 6880 | else if (idx == obj->efile.btf_maps_shndx) |
646f02ff | 6881 | err = bpf_object__collect_map_relos(obj, shdr, data); |
c3c55696 AN |
6882 | else |
6883 | err = bpf_object__collect_prog_relos(obj, shdr, data); | |
34090915 | 6884 | if (err) |
6371ca3b | 6885 | return err; |
34090915 | 6886 | } |
c3c55696 | 6887 | |
d0e92887 | 6888 | bpf_object__sort_relos(obj); |
34090915 WN |
6889 | return 0; |
6890 | } | |
6891 | ||
109cea5a AN |
6892 | static bool insn_is_helper_call(struct bpf_insn *insn, enum bpf_func_id *func_id) |
6893 | { | |
9b2f6fec | 6894 | if (BPF_CLASS(insn->code) == BPF_JMP && |
109cea5a AN |
6895 | BPF_OP(insn->code) == BPF_CALL && |
6896 | BPF_SRC(insn->code) == BPF_K && | |
9b2f6fec AN |
6897 | insn->src_reg == 0 && |
6898 | insn->dst_reg == 0) { | |
6899 | *func_id = insn->imm; | |
109cea5a AN |
6900 | return true; |
6901 | } | |
6902 | return false; | |
6903 | } | |
6904 | ||
42869d28 | 6905 | static int bpf_object__sanitize_prog(struct bpf_object *obj, struct bpf_program *prog) |
109cea5a AN |
6906 | { |
6907 | struct bpf_insn *insn = prog->insns; | |
6908 | enum bpf_func_id func_id; | |
6909 | int i; | |
6910 | ||
67234743 AS |
6911 | if (obj->gen_loader) |
6912 | return 0; | |
6913 | ||
109cea5a AN |
6914 | for (i = 0; i < prog->insns_cnt; i++, insn++) { |
6915 | if (!insn_is_helper_call(insn, &func_id)) | |
6916 | continue; | |
6917 | ||
6918 | /* on kernels that don't yet support | |
6919 | * bpf_probe_read_{kernel,user}[_str] helpers, fall back | |
6920 | * to bpf_probe_read() which works well for old kernels | |
6921 | */ | |
6922 | switch (func_id) { | |
6923 | case BPF_FUNC_probe_read_kernel: | |
6924 | case BPF_FUNC_probe_read_user: | |
9ca1f56a | 6925 | if (!kernel_supports(obj, FEAT_PROBE_READ_KERN)) |
109cea5a AN |
6926 | insn->imm = BPF_FUNC_probe_read; |
6927 | break; | |
6928 | case BPF_FUNC_probe_read_kernel_str: | |
6929 | case BPF_FUNC_probe_read_user_str: | |
9ca1f56a | 6930 | if (!kernel_supports(obj, FEAT_PROBE_READ_KERN)) |
109cea5a AN |
6931 | insn->imm = BPF_FUNC_probe_read_str; |
6932 | break; | |
6933 | default: | |
6934 | break; | |
6935 | } | |
6936 | } | |
6937 | return 0; | |
6938 | } | |
6939 | ||
15ea31fa AN |
6940 | static int libbpf_find_attach_btf_id(struct bpf_program *prog, const char *attach_name, |
6941 | int *btf_obj_fd, int *btf_type_id); | |
12d9466d | 6942 | |
4fa5bcfe AN |
6943 | /* this is called as prog->sec_def->prog_prepare_load_fn for libbpf-supported sec_defs */ |
6944 | static int libbpf_prepare_prog_load(struct bpf_program *prog, | |
6945 | struct bpf_prog_load_opts *opts, long cookie) | |
12d9466d | 6946 | { |
15ea31fa AN |
6947 | enum sec_def_flags def = cookie; |
6948 | ||
12d9466d | 6949 | /* old kernels might not support specifying expected_attach_type */ |
15ea31fa | 6950 | if ((def & SEC_EXP_ATTACH_OPT) && !kernel_supports(prog->obj, FEAT_EXP_ATTACH_TYPE)) |
d10ef2b8 | 6951 | opts->expected_attach_type = 0; |
12d9466d | 6952 | |
15ea31fa | 6953 | if (def & SEC_SLEEPABLE) |
d10ef2b8 | 6954 | opts->prog_flags |= BPF_F_SLEEPABLE; |
12d9466d | 6955 | |
082c4bfb LB |
6956 | if (prog->type == BPF_PROG_TYPE_XDP && (def & SEC_XDP_FRAGS)) |
6957 | opts->prog_flags |= BPF_F_XDP_HAS_FRAGS; | |
6958 | ||
5902da6d JO |
6959 | /* special check for usdt to use uprobe_multi link */ |
6960 | if ((def & SEC_USDT) && kernel_supports(prog->obj, FEAT_UPROBE_MULTI_LINK)) | |
6961 | prog->expected_attach_type = BPF_TRACE_UPROBE_MULTI; | |
6962 | ||
cc7d8f2c | 6963 | if ((def & SEC_ATTACH_BTF) && !prog->attach_btf_id) { |
12d9466d | 6964 | int btf_obj_fd = 0, btf_type_id = 0, err; |
15ea31fa | 6965 | const char *attach_name; |
12d9466d | 6966 | |
cc7d8f2c AN |
6967 | attach_name = strchr(prog->sec_name, '/'); |
6968 | if (!attach_name) { | |
6969 | /* if BPF program is annotated with just SEC("fentry") | |
6970 | * (or similar) without declaratively specifying | |
6971 | * target, then it is expected that target will be | |
6972 | * specified with bpf_program__set_attach_target() at | |
6973 | * runtime before BPF object load step. If not, then | |
6974 | * there is nothing to load into the kernel as BPF | |
6975 | * verifier won't be able to validate BPF program | |
6976 | * correctness anyways. | |
6977 | */ | |
6978 | pr_warn("prog '%s': no BTF-based attach target is specified, use bpf_program__set_attach_target()\n", | |
6979 | prog->name); | |
6980 | return -EINVAL; | |
6981 | } | |
6982 | attach_name++; /* skip over / */ | |
6983 | ||
15ea31fa | 6984 | err = libbpf_find_attach_btf_id(prog, attach_name, &btf_obj_fd, &btf_type_id); |
12d9466d AN |
6985 | if (err) |
6986 | return err; | |
6987 | ||
6988 | /* cache resolved BTF FD and BTF type ID in the prog */ | |
6989 | prog->attach_btf_obj_fd = btf_obj_fd; | |
6990 | prog->attach_btf_id = btf_type_id; | |
6991 | ||
6992 | /* but by now libbpf common logic is not utilizing | |
6993 | * prog->atach_btf_obj_fd/prog->attach_btf_id anymore because | |
d10ef2b8 AN |
6994 | * this callback is called after opts were populated by |
6995 | * libbpf, so this callback has to update opts explicitly here | |
12d9466d | 6996 | */ |
d10ef2b8 AN |
6997 | opts->attach_btf_obj_fd = btf_obj_fd; |
6998 | opts->attach_btf_id = btf_type_id; | |
12d9466d AN |
6999 | } |
7000 | return 0; | |
7001 | } | |
7002 | ||
9fdc4273 AN |
7003 | static void fixup_verifier_log(struct bpf_program *prog, char *buf, size_t buf_sz); |
7004 | ||
cf90a20d AN |
7005 | static int bpf_object_load_prog(struct bpf_object *obj, struct bpf_program *prog, |
7006 | struct bpf_insn *insns, int insns_cnt, | |
7007 | const char *license, __u32 kern_version, int *prog_fd) | |
55cffde2 | 7008 | { |
d10ef2b8 AN |
7009 | LIBBPF_OPTS(bpf_prog_load_opts, load_attr); |
7010 | const char *prog_name = NULL; | |
1ce6a9fc | 7011 | char *cp, errmsg[STRERR_BUFSIZE]; |
8395f320 | 7012 | size_t log_buf_size = 0; |
b3ce9079 | 7013 | char *log_buf = NULL, *tmp; |
12d9466d | 7014 | int btf_fd, ret, err; |
b3ce9079 AN |
7015 | bool own_log_buf = true; |
7016 | __u32 log_level = prog->log_level; | |
55cffde2 | 7017 | |
80b2b5c3 AM |
7018 | if (prog->type == BPF_PROG_TYPE_UNSPEC) { |
7019 | /* | |
7020 | * The program type must be set. Most likely we couldn't find a proper | |
7021 | * section definition at load time, and thus we didn't infer the type. | |
7022 | */ | |
7023 | pr_warn("prog '%s': missing BPF prog type, check ELF section name '%s'\n", | |
7024 | prog->name, prog->sec_name); | |
7025 | return -EINVAL; | |
7026 | } | |
7027 | ||
fba01a06 AN |
7028 | if (!insns || !insns_cnt) |
7029 | return -EINVAL; | |
7030 | ||
25bbbd7a | 7031 | if (kernel_supports(obj, FEAT_PROG_NAME)) |
d10ef2b8 | 7032 | prog_name = prog->name; |
12d9466d AN |
7033 | load_attr.attach_prog_fd = prog->attach_prog_fd; |
7034 | load_attr.attach_btf_obj_fd = prog->attach_btf_obj_fd; | |
6aef10a4 AN |
7035 | load_attr.attach_btf_id = prog->attach_btf_id; |
7036 | load_attr.kern_version = kern_version; | |
7037 | load_attr.prog_ifindex = prog->prog_ifindex; | |
7038 | ||
0f0e55d8 | 7039 | /* specify func_info/line_info only if kernel supports them */ |
25bbbd7a AN |
7040 | btf_fd = bpf_object__btf_fd(obj); |
7041 | if (btf_fd >= 0 && kernel_supports(obj, FEAT_BTF_FUNC)) { | |
0f0e55d8 AN |
7042 | load_attr.prog_btf_fd = btf_fd; |
7043 | load_attr.func_info = prog->func_info; | |
7044 | load_attr.func_info_rec_size = prog->func_info_rec_size; | |
7045 | load_attr.func_info_cnt = prog->func_info_cnt; | |
7046 | load_attr.line_info = prog->line_info; | |
7047 | load_attr.line_info_rec_size = prog->line_info_rec_size; | |
7048 | load_attr.line_info_cnt = prog->line_info_cnt; | |
7049 | } | |
b3ce9079 | 7050 | load_attr.log_level = log_level; |
04656198 | 7051 | load_attr.prog_flags = prog->prog_flags; |
25bbbd7a | 7052 | load_attr.fd_array = obj->fd_array; |
55cffde2 | 7053 | |
12d9466d | 7054 | /* adjust load_attr if sec_def provides custom preload callback */ |
4fa5bcfe AN |
7055 | if (prog->sec_def && prog->sec_def->prog_prepare_load_fn) { |
7056 | err = prog->sec_def->prog_prepare_load_fn(prog, &load_attr, prog->sec_def->cookie); | |
12d9466d AN |
7057 | if (err < 0) { |
7058 | pr_warn("prog '%s': failed to prepare load attributes: %d\n", | |
7059 | prog->name, err); | |
7060 | return err; | |
7061 | } | |
b63b3c49 JO |
7062 | insns = prog->insns; |
7063 | insns_cnt = prog->insns_cnt; | |
12d9466d AN |
7064 | } |
7065 | ||
5902da6d JO |
7066 | /* allow prog_prepare_load_fn to change expected_attach_type */ |
7067 | load_attr.expected_attach_type = prog->expected_attach_type; | |
7068 | ||
25bbbd7a | 7069 | if (obj->gen_loader) { |
d10ef2b8 AN |
7070 | bpf_gen__prog_load(obj->gen_loader, prog->type, prog->name, |
7071 | license, insns, insns_cnt, &load_attr, | |
25bbbd7a | 7072 | prog - obj->programs); |
be2f2d16 | 7073 | *prog_fd = -1; |
67234743 AS |
7074 | return 0; |
7075 | } | |
8395f320 | 7076 | |
b3ce9079 | 7077 | retry_load: |
bb412cf1 | 7078 | /* if log_level is zero, we don't request logs initially even if |
b3ce9079 AN |
7079 | * custom log_buf is specified; if the program load fails, then we'll |
7080 | * bump log_level to 1 and use either custom log_buf or we'll allocate | |
7081 | * our own and retry the load to get details on what failed | |
7082 | */ | |
7083 | if (log_level) { | |
7084 | if (prog->log_buf) { | |
7085 | log_buf = prog->log_buf; | |
7086 | log_buf_size = prog->log_size; | |
7087 | own_log_buf = false; | |
7088 | } else if (obj->log_buf) { | |
7089 | log_buf = obj->log_buf; | |
7090 | log_buf_size = obj->log_size; | |
7091 | own_log_buf = false; | |
7092 | } else { | |
7093 | log_buf_size = max((size_t)BPF_LOG_BUF_SIZE, log_buf_size * 2); | |
7094 | tmp = realloc(log_buf, log_buf_size); | |
7095 | if (!tmp) { | |
7096 | ret = -ENOMEM; | |
7097 | goto out; | |
7098 | } | |
7099 | log_buf = tmp; | |
7100 | log_buf[0] = '\0'; | |
7101 | own_log_buf = true; | |
7102 | } | |
8395f320 | 7103 | } |
55cffde2 | 7104 | |
6aef10a4 | 7105 | load_attr.log_buf = log_buf; |
d10ef2b8 | 7106 | load_attr.log_size = log_buf_size; |
b3ce9079 | 7107 | load_attr.log_level = log_level; |
55cffde2 | 7108 | |
b3ce9079 | 7109 | ret = bpf_prog_load(prog->type, prog_name, license, insns, insns_cnt, &load_attr); |
55cffde2 | 7110 | if (ret >= 0) { |
b3ce9079 | 7111 | if (log_level && own_log_buf) { |
ad9a7f96 AN |
7112 | pr_debug("prog '%s': -- BEGIN PROG LOAD LOG --\n%s-- END PROG LOAD LOG --\n", |
7113 | prog->name, log_buf); | |
7114 | } | |
5d23328d | 7115 | |
25bbbd7a AN |
7116 | if (obj->has_rodata && kernel_supports(obj, FEAT_PROG_BIND_MAP)) { |
7117 | struct bpf_map *map; | |
7118 | int i; | |
7119 | ||
7120 | for (i = 0; i < obj->nr_maps; i++) { | |
7121 | map = &prog->obj->maps[i]; | |
7122 | if (map->libbpf_type != LIBBPF_MAP_RODATA) | |
7123 | continue; | |
5d23328d | 7124 | |
25bbbd7a AN |
7125 | if (bpf_prog_bind_map(ret, bpf_map__fd(map), NULL)) { |
7126 | cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); | |
ad9a7f96 AN |
7127 | pr_warn("prog '%s': failed to bind map '%s': %s\n", |
7128 | prog->name, map->real_name, cp); | |
25bbbd7a AN |
7129 | /* Don't fail hard if can't bind rodata. */ |
7130 | } | |
5d23328d YZ |
7131 | } |
7132 | } | |
7133 | ||
be2f2d16 | 7134 | *prog_fd = ret; |
55cffde2 WN |
7135 | ret = 0; |
7136 | goto out; | |
7137 | } | |
7138 | ||
b3ce9079 AN |
7139 | if (log_level == 0) { |
7140 | log_level = 1; | |
da11b417 AS |
7141 | goto retry_load; |
7142 | } | |
b3ce9079 AN |
7143 | /* On ENOSPC, increase log buffer size and retry, unless custom |
7144 | * log_buf is specified. | |
7145 | * Be careful to not overflow u32, though. Kernel's log buf size limit | |
7146 | * isn't part of UAPI so it can always be bumped to full 4GB. So don't | |
7147 | * multiply by 2 unless we are sure we'll fit within 32 bits. | |
7148 | * Currently, we'll get -EINVAL when we reach (UINT_MAX >> 2). | |
7149 | */ | |
7150 | if (own_log_buf && errno == ENOSPC && log_buf_size <= UINT_MAX / 2) | |
7151 | goto retry_load; | |
2eda2145 AN |
7152 | |
7153 | ret = -errno; | |
9fdc4273 AN |
7154 | |
7155 | /* post-process verifier log to improve error descriptions */ | |
7156 | fixup_verifier_log(prog, log_buf, log_buf_size); | |
7157 | ||
24d6a808 | 7158 | cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
ad9a7f96 | 7159 | pr_warn("prog '%s': BPF program load failed: %s\n", prog->name, cp); |
dc3a2d25 | 7160 | pr_perm_msg(ret); |
55cffde2 | 7161 | |
b3ce9079 | 7162 | if (own_log_buf && log_buf && log_buf[0] != '\0') { |
ad9a7f96 AN |
7163 | pr_warn("prog '%s': -- BEGIN PROG LOAD LOG --\n%s-- END PROG LOAD LOG --\n", |
7164 | prog->name, log_buf); | |
7165 | } | |
55cffde2 WN |
7166 | |
7167 | out: | |
b3ce9079 AN |
7168 | if (own_log_buf) |
7169 | free(log_buf); | |
55cffde2 WN |
7170 | return ret; |
7171 | } | |
7172 | ||
9fdc4273 AN |
7173 | static char *find_prev_line(char *buf, char *cur) |
7174 | { | |
7175 | char *p; | |
7176 | ||
7177 | if (cur == buf) /* end of a log buf */ | |
7178 | return NULL; | |
7179 | ||
7180 | p = cur - 1; | |
7181 | while (p - 1 >= buf && *(p - 1) != '\n') | |
7182 | p--; | |
7183 | ||
7184 | return p; | |
7185 | } | |
7186 | ||
7187 | static void patch_log(char *buf, size_t buf_sz, size_t log_sz, | |
7188 | char *orig, size_t orig_sz, const char *patch) | |
7189 | { | |
7190 | /* size of the remaining log content to the right from the to-be-replaced part */ | |
7191 | size_t rem_sz = (buf + log_sz) - (orig + orig_sz); | |
7192 | size_t patch_sz = strlen(patch); | |
7193 | ||
7194 | if (patch_sz != orig_sz) { | |
7195 | /* If patch line(s) are longer than original piece of verifier log, | |
7196 | * shift log contents by (patch_sz - orig_sz) bytes to the right | |
7197 | * starting from after to-be-replaced part of the log. | |
7198 | * | |
7199 | * If patch line(s) are shorter than original piece of verifier log, | |
7200 | * shift log contents by (orig_sz - patch_sz) bytes to the left | |
7201 | * starting from after to-be-replaced part of the log | |
7202 | * | |
7203 | * We need to be careful about not overflowing available | |
7204 | * buf_sz capacity. If that's the case, we'll truncate the end | |
7205 | * of the original log, as necessary. | |
7206 | */ | |
7207 | if (patch_sz > orig_sz) { | |
7208 | if (orig + patch_sz >= buf + buf_sz) { | |
7209 | /* patch is big enough to cover remaining space completely */ | |
7210 | patch_sz -= (orig + patch_sz) - (buf + buf_sz) + 1; | |
7211 | rem_sz = 0; | |
7212 | } else if (patch_sz - orig_sz > buf_sz - log_sz) { | |
7213 | /* patch causes part of remaining log to be truncated */ | |
7214 | rem_sz -= (patch_sz - orig_sz) - (buf_sz - log_sz); | |
7215 | } | |
7216 | } | |
7217 | /* shift remaining log to the right by calculated amount */ | |
7218 | memmove(orig + patch_sz, orig + orig_sz, rem_sz); | |
7219 | } | |
7220 | ||
7221 | memcpy(orig, patch, patch_sz); | |
7222 | } | |
7223 | ||
7224 | static void fixup_log_failed_core_relo(struct bpf_program *prog, | |
7225 | char *buf, size_t buf_sz, size_t log_sz, | |
7226 | char *line1, char *line2, char *line3) | |
7227 | { | |
7228 | /* Expected log for failed and not properly guarded CO-RE relocation: | |
7229 | * line1 -> 123: (85) call unknown#195896080 | |
7230 | * line2 -> invalid func unknown#195896080 | |
7231 | * line3 -> <anything else or end of buffer> | |
7232 | * | |
7233 | * "123" is the index of the instruction that was poisoned. We extract | |
7234 | * instruction index to find corresponding CO-RE relocation and | |
7235 | * replace this part of the log with more relevant information about | |
7236 | * failed CO-RE relocation. | |
7237 | */ | |
7238 | const struct bpf_core_relo *relo; | |
7239 | struct bpf_core_spec spec; | |
7240 | char patch[512], spec_buf[256]; | |
b198881d | 7241 | int insn_idx, err, spec_len; |
9fdc4273 AN |
7242 | |
7243 | if (sscanf(line1, "%d: (%*d) call unknown#195896080\n", &insn_idx) != 1) | |
7244 | return; | |
7245 | ||
7246 | relo = find_relo_core(prog, insn_idx); | |
7247 | if (!relo) | |
7248 | return; | |
7249 | ||
7250 | err = bpf_core_parse_spec(prog->name, prog->obj->btf, relo, &spec); | |
7251 | if (err) | |
7252 | return; | |
7253 | ||
b198881d | 7254 | spec_len = bpf_core_format_spec(spec_buf, sizeof(spec_buf), &spec); |
9fdc4273 AN |
7255 | snprintf(patch, sizeof(patch), |
7256 | "%d: <invalid CO-RE relocation>\n" | |
b198881d AN |
7257 | "failed to resolve CO-RE relocation %s%s\n", |
7258 | insn_idx, spec_buf, spec_len >= sizeof(spec_buf) ? "..." : ""); | |
9fdc4273 AN |
7259 | |
7260 | patch_log(buf, buf_sz, log_sz, line1, line3 - line1, patch); | |
7261 | } | |
7262 | ||
ec41817b AN |
7263 | static void fixup_log_missing_map_load(struct bpf_program *prog, |
7264 | char *buf, size_t buf_sz, size_t log_sz, | |
7265 | char *line1, char *line2, char *line3) | |
7266 | { | |
3055ddd6 | 7267 | /* Expected log for failed and not properly guarded map reference: |
ec41817b AN |
7268 | * line1 -> 123: (85) call unknown#2001000345 |
7269 | * line2 -> invalid func unknown#2001000345 | |
7270 | * line3 -> <anything else or end of buffer> | |
7271 | * | |
7272 | * "123" is the index of the instruction that was poisoned. | |
3055ddd6 | 7273 | * "345" in "2001000345" is a map index in obj->maps to fetch map name. |
ec41817b AN |
7274 | */ |
7275 | struct bpf_object *obj = prog->obj; | |
7276 | const struct bpf_map *map; | |
7277 | int insn_idx, map_idx; | |
7278 | char patch[128]; | |
7279 | ||
7280 | if (sscanf(line1, "%d: (%*d) call unknown#%d\n", &insn_idx, &map_idx) != 2) | |
7281 | return; | |
7282 | ||
3055ddd6 | 7283 | map_idx -= POISON_LDIMM64_MAP_BASE; |
ec41817b AN |
7284 | if (map_idx < 0 || map_idx >= obj->nr_maps) |
7285 | return; | |
7286 | map = &obj->maps[map_idx]; | |
7287 | ||
7288 | snprintf(patch, sizeof(patch), | |
7289 | "%d: <invalid BPF map reference>\n" | |
7290 | "BPF map '%s' is referenced but wasn't created\n", | |
7291 | insn_idx, map->name); | |
7292 | ||
7293 | patch_log(buf, buf_sz, log_sz, line1, line3 - line1, patch); | |
7294 | } | |
7295 | ||
05b6f766 AN |
7296 | static void fixup_log_missing_kfunc_call(struct bpf_program *prog, |
7297 | char *buf, size_t buf_sz, size_t log_sz, | |
7298 | char *line1, char *line2, char *line3) | |
7299 | { | |
7300 | /* Expected log for failed and not properly guarded kfunc call: | |
7301 | * line1 -> 123: (85) call unknown#2002000345 | |
7302 | * line2 -> invalid func unknown#2002000345 | |
7303 | * line3 -> <anything else or end of buffer> | |
7304 | * | |
7305 | * "123" is the index of the instruction that was poisoned. | |
7306 | * "345" in "2002000345" is an extern index in obj->externs to fetch kfunc name. | |
7307 | */ | |
7308 | struct bpf_object *obj = prog->obj; | |
7309 | const struct extern_desc *ext; | |
7310 | int insn_idx, ext_idx; | |
7311 | char patch[128]; | |
7312 | ||
7313 | if (sscanf(line1, "%d: (%*d) call unknown#%d\n", &insn_idx, &ext_idx) != 2) | |
7314 | return; | |
7315 | ||
7316 | ext_idx -= POISON_CALL_KFUNC_BASE; | |
7317 | if (ext_idx < 0 || ext_idx >= obj->nr_extern) | |
7318 | return; | |
7319 | ext = &obj->externs[ext_idx]; | |
7320 | ||
7321 | snprintf(patch, sizeof(patch), | |
7322 | "%d: <invalid kfunc call>\n" | |
7323 | "kfunc '%s' is referenced but wasn't resolved\n", | |
7324 | insn_idx, ext->name); | |
7325 | ||
7326 | patch_log(buf, buf_sz, log_sz, line1, line3 - line1, patch); | |
7327 | } | |
7328 | ||
9fdc4273 AN |
7329 | static void fixup_verifier_log(struct bpf_program *prog, char *buf, size_t buf_sz) |
7330 | { | |
7331 | /* look for familiar error patterns in last N lines of the log */ | |
7332 | const size_t max_last_line_cnt = 10; | |
7333 | char *prev_line, *cur_line, *next_line; | |
7334 | size_t log_sz; | |
7335 | int i; | |
7336 | ||
7337 | if (!buf) | |
7338 | return; | |
7339 | ||
7340 | log_sz = strlen(buf) + 1; | |
7341 | next_line = buf + log_sz - 1; | |
7342 | ||
7343 | for (i = 0; i < max_last_line_cnt; i++, next_line = cur_line) { | |
7344 | cur_line = find_prev_line(buf, next_line); | |
7345 | if (!cur_line) | |
7346 | return; | |
7347 | ||
9fdc4273 AN |
7348 | if (str_has_pfx(cur_line, "invalid func unknown#195896080\n")) { |
7349 | prev_line = find_prev_line(buf, cur_line); | |
7350 | if (!prev_line) | |
7351 | continue; | |
7352 | ||
3055ddd6 | 7353 | /* failed CO-RE relocation case */ |
9fdc4273 AN |
7354 | fixup_log_failed_core_relo(prog, buf, buf_sz, log_sz, |
7355 | prev_line, cur_line, next_line); | |
7356 | return; | |
3055ddd6 | 7357 | } else if (str_has_pfx(cur_line, "invalid func unknown#"POISON_LDIMM64_MAP_PFX)) { |
ec41817b AN |
7358 | prev_line = find_prev_line(buf, cur_line); |
7359 | if (!prev_line) | |
7360 | continue; | |
7361 | ||
3055ddd6 | 7362 | /* reference to uncreated BPF map */ |
ec41817b AN |
7363 | fixup_log_missing_map_load(prog, buf, buf_sz, log_sz, |
7364 | prev_line, cur_line, next_line); | |
7365 | return; | |
05b6f766 AN |
7366 | } else if (str_has_pfx(cur_line, "invalid func unknown#"POISON_CALL_KFUNC_PFX)) { |
7367 | prev_line = find_prev_line(buf, cur_line); | |
7368 | if (!prev_line) | |
7369 | continue; | |
7370 | ||
7371 | /* reference to unresolved kfunc */ | |
7372 | fixup_log_missing_kfunc_call(prog, buf, buf_sz, log_sz, | |
7373 | prev_line, cur_line, next_line); | |
7374 | return; | |
9fdc4273 AN |
7375 | } |
7376 | } | |
7377 | } | |
7378 | ||
d0e92887 | 7379 | static int bpf_program_record_relos(struct bpf_program *prog) |
67234743 AS |
7380 | { |
7381 | struct bpf_object *obj = prog->obj; | |
7382 | int i; | |
7383 | ||
7384 | for (i = 0; i < prog->nr_reloc; i++) { | |
7385 | struct reloc_desc *relo = &prog->reloc_desc[i]; | |
3055ddd6 | 7386 | struct extern_desc *ext = &obj->externs[relo->ext_idx]; |
708cdc57 | 7387 | int kind; |
67234743 AS |
7388 | |
7389 | switch (relo->type) { | |
a18f7214 | 7390 | case RELO_EXTERN_LD64: |
67234743 AS |
7391 | if (ext->type != EXT_KSYM) |
7392 | continue; | |
708cdc57 AS |
7393 | kind = btf_is_var(btf__type_by_id(obj->btf, ext->btf_id)) ? |
7394 | BTF_KIND_VAR : BTF_KIND_FUNC; | |
c24941cd KKD |
7395 | bpf_gen__record_extern(obj->gen_loader, ext->name, |
7396 | ext->is_weak, !ext->ksym.type_id, | |
708cdc57 | 7397 | true, kind, relo->insn_idx); |
67234743 | 7398 | break; |
a18f7214 | 7399 | case RELO_EXTERN_CALL: |
c24941cd | 7400 | bpf_gen__record_extern(obj->gen_loader, ext->name, |
708cdc57 | 7401 | ext->is_weak, false, false, BTF_KIND_FUNC, |
67234743 AS |
7402 | relo->insn_idx); |
7403 | break; | |
d0e92887 AS |
7404 | case RELO_CORE: { |
7405 | struct bpf_core_relo cr = { | |
7406 | .insn_off = relo->insn_idx * 8, | |
7407 | .type_id = relo->core_relo->type_id, | |
7408 | .access_str_off = relo->core_relo->access_str_off, | |
7409 | .kind = relo->core_relo->kind, | |
7410 | }; | |
7411 | ||
7412 | bpf_gen__record_relo_core(obj->gen_loader, &cr); | |
7413 | break; | |
7414 | } | |
67234743 AS |
7415 | default: |
7416 | continue; | |
7417 | } | |
7418 | } | |
7419 | return 0; | |
7420 | } | |
7421 | ||
55cffde2 | 7422 | static int |
60276f98 | 7423 | bpf_object__load_progs(struct bpf_object *obj, int log_level) |
55cffde2 | 7424 | { |
d9297581 | 7425 | struct bpf_program *prog; |
55cffde2 WN |
7426 | size_t i; |
7427 | int err; | |
7428 | ||
109cea5a AN |
7429 | for (i = 0; i < obj->nr_programs; i++) { |
7430 | prog = &obj->programs[i]; | |
7431 | err = bpf_object__sanitize_prog(obj, prog); | |
7432 | if (err) | |
7433 | return err; | |
7434 | } | |
7435 | ||
55cffde2 | 7436 | for (i = 0; i < obj->nr_programs; i++) { |
d9297581 | 7437 | prog = &obj->programs[i]; |
c3c55696 | 7438 | if (prog_is_subprog(obj, prog)) |
48cca7e4 | 7439 | continue; |
a3820c48 | 7440 | if (!prog->autoload) { |
9c0f8cbd | 7441 | pr_debug("prog '%s': skipped loading\n", prog->name); |
d9297581 AN |
7442 | continue; |
7443 | } | |
7444 | prog->log_level |= log_level; | |
cf90a20d AN |
7445 | |
7446 | if (obj->gen_loader) | |
7447 | bpf_program_record_relos(prog); | |
7448 | ||
7449 | err = bpf_object_load_prog(obj, prog, prog->insns, prog->insns_cnt, | |
7450 | obj->license, obj->kern_version, &prog->fd); | |
7451 | if (err) { | |
7452 | pr_warn("prog '%s': failed to load: %d\n", prog->name, err); | |
55cffde2 | 7453 | return err; |
cf90a20d | 7454 | } |
55cffde2 | 7455 | } |
185cfe83 AN |
7456 | |
7457 | bpf_object__free_relocs(obj); | |
55cffde2 WN |
7458 | return 0; |
7459 | } | |
7460 | ||
25498a19 AN |
7461 | static const struct bpf_sec_def *find_sec_def(const char *sec_name); |
7462 | ||
91b4d1d1 AN |
7463 | static int bpf_object_init_progs(struct bpf_object *obj, const struct bpf_object_open_opts *opts) |
7464 | { | |
7465 | struct bpf_program *prog; | |
12d9466d | 7466 | int err; |
91b4d1d1 AN |
7467 | |
7468 | bpf_object__for_each_program(prog, obj) { | |
7469 | prog->sec_def = find_sec_def(prog->sec_name); | |
7470 | if (!prog->sec_def) { | |
7471 | /* couldn't guess, but user might manually specify */ | |
7472 | pr_debug("prog '%s': unrecognized ELF section name '%s'\n", | |
7473 | prog->name, prog->sec_name); | |
7474 | continue; | |
7475 | } | |
7476 | ||
df286716 GS |
7477 | prog->type = prog->sec_def->prog_type; |
7478 | prog->expected_attach_type = prog->sec_def->expected_attach_type; | |
91b4d1d1 | 7479 | |
12d9466d AN |
7480 | /* sec_def can have custom callback which should be called |
7481 | * after bpf_program is initialized to adjust its properties | |
7482 | */ | |
4fa5bcfe AN |
7483 | if (prog->sec_def->prog_setup_fn) { |
7484 | err = prog->sec_def->prog_setup_fn(prog, prog->sec_def->cookie); | |
12d9466d AN |
7485 | if (err < 0) { |
7486 | pr_warn("prog '%s': failed to initialize: %d\n", | |
7487 | prog->name, err); | |
7488 | return err; | |
7489 | } | |
7490 | } | |
91b4d1d1 AN |
7491 | } |
7492 | ||
7493 | return 0; | |
7494 | } | |
7495 | ||
ad9a7f96 AN |
7496 | static struct bpf_object *bpf_object_open(const char *path, const void *obj_buf, size_t obj_buf_sz, |
7497 | const struct bpf_object_open_opts *opts) | |
1a5e3fb1 | 7498 | { |
1373ff59 | 7499 | const char *obj_name, *kconfig, *btf_tmp_path; |
1a5e3fb1 | 7500 | struct bpf_object *obj; |
291ee02b | 7501 | char tmp_name[64]; |
6371ca3b | 7502 | int err; |
e0e3ea88 AN |
7503 | char *log_buf; |
7504 | size_t log_size; | |
7505 | __u32 log_level; | |
1a5e3fb1 WN |
7506 | |
7507 | if (elf_version(EV_CURRENT) == EV_NONE) { | |
be18010e KW |
7508 | pr_warn("failed to init libelf for %s\n", |
7509 | path ? : "(mem buf)"); | |
6371ca3b | 7510 | return ERR_PTR(-LIBBPF_ERRNO__LIBELF); |
1a5e3fb1 WN |
7511 | } |
7512 | ||
291ee02b AN |
7513 | if (!OPTS_VALID(opts, bpf_object_open_opts)) |
7514 | return ERR_PTR(-EINVAL); | |
7515 | ||
1aace10f | 7516 | obj_name = OPTS_GET(opts, object_name, NULL); |
291ee02b AN |
7517 | if (obj_buf) { |
7518 | if (!obj_name) { | |
7519 | snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx", | |
7520 | (unsigned long)obj_buf, | |
7521 | (unsigned long)obj_buf_sz); | |
7522 | obj_name = tmp_name; | |
7523 | } | |
7524 | path = obj_name; | |
7525 | pr_debug("loading object '%s' from buffer\n", obj_name); | |
7526 | } | |
7527 | ||
e0e3ea88 AN |
7528 | log_buf = OPTS_GET(opts, kernel_log_buf, NULL); |
7529 | log_size = OPTS_GET(opts, kernel_log_size, 0); | |
7530 | log_level = OPTS_GET(opts, kernel_log_level, 0); | |
7531 | if (log_size > UINT_MAX) | |
7532 | return ERR_PTR(-EINVAL); | |
7533 | if (log_size && !log_buf) | |
7534 | return ERR_PTR(-EINVAL); | |
7535 | ||
2ce8450e | 7536 | obj = bpf_object__new(path, obj_buf, obj_buf_sz, obj_name); |
6371ca3b WN |
7537 | if (IS_ERR(obj)) |
7538 | return obj; | |
1a5e3fb1 | 7539 | |
e0e3ea88 AN |
7540 | obj->log_buf = log_buf; |
7541 | obj->log_size = log_size; | |
7542 | obj->log_level = log_level; | |
7543 | ||
1373ff59 SC |
7544 | btf_tmp_path = OPTS_GET(opts, btf_custom_path, NULL); |
7545 | if (btf_tmp_path) { | |
7546 | if (strlen(btf_tmp_path) >= PATH_MAX) { | |
7547 | err = -ENAMETOOLONG; | |
7548 | goto out; | |
7549 | } | |
7550 | obj->btf_custom_path = strdup(btf_tmp_path); | |
7551 | if (!obj->btf_custom_path) { | |
7552 | err = -ENOMEM; | |
7553 | goto out; | |
7554 | } | |
7555 | } | |
7556 | ||
8601fd42 AN |
7557 | kconfig = OPTS_GET(opts, kconfig, NULL); |
7558 | if (kconfig) { | |
7559 | obj->kconfig = strdup(kconfig); | |
18353c87 SC |
7560 | if (!obj->kconfig) { |
7561 | err = -ENOMEM; | |
7562 | goto out; | |
7563 | } | |
166750bc | 7564 | } |
291ee02b | 7565 | |
0d13bfce AN |
7566 | err = bpf_object__elf_init(obj); |
7567 | err = err ? : bpf_object__check_endianness(obj); | |
7568 | err = err ? : bpf_object__elf_collect(obj); | |
166750bc | 7569 | err = err ? : bpf_object__collect_externs(obj); |
f33f742d | 7570 | err = err ? : bpf_object_fixup_btf(obj); |
0d13bfce | 7571 | err = err ? : bpf_object__init_maps(obj, opts); |
91b4d1d1 | 7572 | err = err ? : bpf_object_init_progs(obj, opts); |
c3c55696 | 7573 | err = err ? : bpf_object__collect_relos(obj); |
0d13bfce AN |
7574 | if (err) |
7575 | goto out; | |
dd4436bb | 7576 | |
91b4d1d1 | 7577 | bpf_object__elf_finish(obj); |
dd4436bb | 7578 | |
1a5e3fb1 WN |
7579 | return obj; |
7580 | out: | |
7581 | bpf_object__close(obj); | |
6371ca3b | 7582 | return ERR_PTR(err); |
1a5e3fb1 WN |
7583 | } |
7584 | ||
2ce8450e | 7585 | struct bpf_object * |
01af3bf0 | 7586 | bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts) |
2ce8450e | 7587 | { |
2ce8450e | 7588 | if (!path) |
e9fc3ce9 | 7589 | return libbpf_err_ptr(-EINVAL); |
2ce8450e AN |
7590 | |
7591 | pr_debug("loading %s\n", path); | |
7592 | ||
ad9a7f96 | 7593 | return libbpf_ptr(bpf_object_open(path, NULL, 0, opts)); |
2ce8450e AN |
7594 | } |
7595 | ||
146bf811 AN |
7596 | struct bpf_object *bpf_object__open(const char *path) |
7597 | { | |
7598 | return bpf_object__open_file(path, NULL); | |
7599 | } | |
7600 | ||
2ce8450e AN |
7601 | struct bpf_object * |
7602 | bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz, | |
01af3bf0 | 7603 | const struct bpf_object_open_opts *opts) |
6c956392 | 7604 | { |
2ce8450e | 7605 | if (!obj_buf || obj_buf_sz == 0) |
e9fc3ce9 | 7606 | return libbpf_err_ptr(-EINVAL); |
6c956392 | 7607 | |
ad9a7f96 | 7608 | return libbpf_ptr(bpf_object_open(NULL, obj_buf, obj_buf_sz, opts)); |
2ce8450e AN |
7609 | } |
7610 | ||
4a404a7e | 7611 | static int bpf_object_unload(struct bpf_object *obj) |
52d3352e WN |
7612 | { |
7613 | size_t i; | |
7614 | ||
7615 | if (!obj) | |
e9fc3ce9 | 7616 | return libbpf_err(-EINVAL); |
52d3352e | 7617 | |
590a0088 | 7618 | for (i = 0; i < obj->nr_maps; i++) { |
9d759a9b | 7619 | zclose(obj->maps[i].fd); |
590a0088 MKL |
7620 | if (obj->maps[i].st_ops) |
7621 | zfree(&obj->maps[i].st_ops->kern_vdata); | |
7622 | } | |
52d3352e | 7623 | |
55cffde2 WN |
7624 | for (i = 0; i < obj->nr_programs; i++) |
7625 | bpf_program__unload(&obj->programs[i]); | |
7626 | ||
52d3352e WN |
7627 | return 0; |
7628 | } | |
7629 | ||
0d13bfce AN |
7630 | static int bpf_object__sanitize_maps(struct bpf_object *obj) |
7631 | { | |
7632 | struct bpf_map *m; | |
7633 | ||
7634 | bpf_object__for_each_map(m, obj) { | |
7635 | if (!bpf_map__is_internal(m)) | |
7636 | continue; | |
9ca1f56a | 7637 | if (!kernel_supports(obj, FEAT_ARRAY_MMAP)) |
6920b086 | 7638 | m->def.map_flags &= ~BPF_F_MMAPABLE; |
0d13bfce AN |
7639 | } |
7640 | ||
7641 | return 0; | |
7642 | } | |
7643 | ||
85153ac0 | 7644 | int libbpf_kallsyms_parse(kallsyms_cb_t cb, void *ctx) |
1c0c7074 AN |
7645 | { |
7646 | char sym_type, sym_name[500]; | |
7647 | unsigned long long sym_addr; | |
1c0c7074 AN |
7648 | int ret, err = 0; |
7649 | FILE *f; | |
7650 | ||
59842c54 | 7651 | f = fopen("/proc/kallsyms", "re"); |
1c0c7074 AN |
7652 | if (!f) { |
7653 | err = -errno; | |
7654 | pr_warn("failed to open /proc/kallsyms: %d\n", err); | |
7655 | return err; | |
7656 | } | |
7657 | ||
7658 | while (true) { | |
7659 | ret = fscanf(f, "%llx %c %499s%*[^\n]\n", | |
7660 | &sym_addr, &sym_type, sym_name); | |
7661 | if (ret == EOF && feof(f)) | |
7662 | break; | |
7663 | if (ret != 3) { | |
135c783f | 7664 | pr_warn("failed to read kallsyms entry: %d\n", ret); |
1c0c7074 | 7665 | err = -EINVAL; |
85153ac0 | 7666 | break; |
1c0c7074 AN |
7667 | } |
7668 | ||
85153ac0 JO |
7669 | err = cb(sym_addr, sym_type, sym_name, ctx); |
7670 | if (err) | |
7671 | break; | |
1c0c7074 AN |
7672 | } |
7673 | ||
1c0c7074 AN |
7674 | fclose(f); |
7675 | return err; | |
7676 | } | |
7677 | ||
85153ac0 JO |
7678 | static int kallsyms_cb(unsigned long long sym_addr, char sym_type, |
7679 | const char *sym_name, void *ctx) | |
7680 | { | |
7681 | struct bpf_object *obj = ctx; | |
7682 | const struct btf_type *t; | |
7683 | struct extern_desc *ext; | |
7684 | ||
7685 | ext = find_extern_by_name(obj, sym_name); | |
7686 | if (!ext || ext->type != EXT_KSYM) | |
7687 | return 0; | |
7688 | ||
7689 | t = btf__type_by_id(obj->btf, ext->btf_id); | |
7690 | if (!btf_is_var(t)) | |
7691 | return 0; | |
7692 | ||
7693 | if (ext->is_set && ext->ksym.addr != sym_addr) { | |
55d00c37 | 7694 | pr_warn("extern (ksym) '%s': resolution is ambiguous: 0x%llx or 0x%llx\n", |
85153ac0 JO |
7695 | sym_name, ext->ksym.addr, sym_addr); |
7696 | return -EINVAL; | |
7697 | } | |
7698 | if (!ext->is_set) { | |
7699 | ext->is_set = true; | |
7700 | ext->ksym.addr = sym_addr; | |
55d00c37 | 7701 | pr_debug("extern (ksym) '%s': set to 0x%llx\n", sym_name, sym_addr); |
85153ac0 JO |
7702 | } |
7703 | return 0; | |
7704 | } | |
7705 | ||
7706 | static int bpf_object__read_kallsyms_file(struct bpf_object *obj) | |
7707 | { | |
7708 | return libbpf_kallsyms_parse(kallsyms_cb, obj); | |
7709 | } | |
7710 | ||
774e132e MKL |
7711 | static int find_ksym_btf_id(struct bpf_object *obj, const char *ksym_name, |
7712 | __u16 kind, struct btf **res_btf, | |
9dbe6015 | 7713 | struct module_btf **res_mod_btf) |
d370bbe1 | 7714 | { |
9dbe6015 | 7715 | struct module_btf *mod_btf; |
284d2587 | 7716 | struct btf *btf; |
9dbe6015 | 7717 | int i, id, err; |
d370bbe1 | 7718 | |
933d1aa3 | 7719 | btf = obj->btf_vmlinux; |
9dbe6015 | 7720 | mod_btf = NULL; |
774e132e MKL |
7721 | id = btf__find_by_name_kind(btf, ksym_name, kind); |
7722 | ||
933d1aa3 MKL |
7723 | if (id == -ENOENT) { |
7724 | err = load_module_btfs(obj); | |
7725 | if (err) | |
7726 | return err; | |
d370bbe1 | 7727 | |
933d1aa3 | 7728 | for (i = 0; i < obj->btf_module_cnt; i++) { |
9dbe6015 KKD |
7729 | /* we assume module_btf's BTF FD is always >0 */ |
7730 | mod_btf = &obj->btf_modules[i]; | |
7731 | btf = mod_btf->btf; | |
7732 | id = btf__find_by_name_kind_own(btf, ksym_name, kind); | |
933d1aa3 MKL |
7733 | if (id != -ENOENT) |
7734 | break; | |
7735 | } | |
7736 | } | |
2211c825 | 7737 | if (id <= 0) |
933d1aa3 | 7738 | return -ESRCH; |
d370bbe1 | 7739 | |
774e132e | 7740 | *res_btf = btf; |
9dbe6015 | 7741 | *res_mod_btf = mod_btf; |
774e132e MKL |
7742 | return id; |
7743 | } | |
7744 | ||
7745 | static int bpf_object__resolve_ksym_var_btf_id(struct bpf_object *obj, | |
7746 | struct extern_desc *ext) | |
7747 | { | |
7748 | const struct btf_type *targ_var, *targ_type; | |
7749 | __u32 targ_type_id, local_type_id; | |
9dbe6015 | 7750 | struct module_btf *mod_btf = NULL; |
774e132e | 7751 | const char *targ_var_name; |
774e132e | 7752 | struct btf *btf = NULL; |
9dbe6015 | 7753 | int id, err; |
774e132e | 7754 | |
9dbe6015 | 7755 | id = find_ksym_btf_id(obj, ext->name, BTF_KIND_VAR, &btf, &mod_btf); |
466b2e13 KKD |
7756 | if (id < 0) { |
7757 | if (id == -ESRCH && ext->is_weak) | |
7758 | return 0; | |
2211c825 HL |
7759 | pr_warn("extern (var ksym) '%s': not found in kernel BTF\n", |
7760 | ext->name); | |
774e132e | 7761 | return id; |
2211c825 | 7762 | } |
774e132e | 7763 | |
933d1aa3 MKL |
7764 | /* find local type_id */ |
7765 | local_type_id = ext->ksym.type_id; | |
284d2587 | 7766 | |
933d1aa3 MKL |
7767 | /* find target type_id */ |
7768 | targ_var = btf__type_by_id(btf, id); | |
7769 | targ_var_name = btf__name_by_offset(btf, targ_var->name_off); | |
7770 | targ_type = skip_mods_and_typedefs(btf, targ_var->type, &targ_type_id); | |
d370bbe1 | 7771 | |
933d1aa3 MKL |
7772 | err = bpf_core_types_are_compat(obj->btf, local_type_id, |
7773 | btf, targ_type_id); | |
7774 | if (err <= 0) { | |
7775 | const struct btf_type *local_type; | |
7776 | const char *targ_name, *local_name; | |
d370bbe1 | 7777 | |
933d1aa3 MKL |
7778 | local_type = btf__type_by_id(obj->btf, local_type_id); |
7779 | local_name = btf__name_by_offset(obj->btf, local_type->name_off); | |
7780 | targ_name = btf__name_by_offset(btf, targ_type->name_off); | |
d370bbe1 | 7781 | |
933d1aa3 MKL |
7782 | pr_warn("extern (var ksym) '%s': incompatible types, expected [%d] %s %s, but kernel has [%d] %s %s\n", |
7783 | ext->name, local_type_id, | |
7784 | btf_kind_str(local_type), local_name, targ_type_id, | |
7785 | btf_kind_str(targ_type), targ_name); | |
7786 | return -EINVAL; | |
7787 | } | |
d370bbe1 | 7788 | |
933d1aa3 | 7789 | ext->is_set = true; |
9dbe6015 | 7790 | ext->ksym.kernel_btf_obj_fd = mod_btf ? mod_btf->fd : 0; |
933d1aa3 MKL |
7791 | ext->ksym.kernel_btf_id = id; |
7792 | pr_debug("extern (var ksym) '%s': resolved to [%d] %s %s\n", | |
7793 | ext->name, id, btf_kind_str(targ_var), targ_var_name); | |
d370bbe1 | 7794 | |
933d1aa3 MKL |
7795 | return 0; |
7796 | } | |
d370bbe1 | 7797 | |
5bd022ec MKL |
7798 | static int bpf_object__resolve_ksym_func_btf_id(struct bpf_object *obj, |
7799 | struct extern_desc *ext) | |
7800 | { | |
7801 | int local_func_proto_id, kfunc_proto_id, kfunc_id; | |
9dbe6015 | 7802 | struct module_btf *mod_btf = NULL; |
5bd022ec MKL |
7803 | const struct btf_type *kern_func; |
7804 | struct btf *kern_btf = NULL; | |
9dbe6015 | 7805 | int ret; |
5bd022ec MKL |
7806 | |
7807 | local_func_proto_id = ext->ksym.type_id; | |
7808 | ||
5964a223 DM |
7809 | kfunc_id = find_ksym_btf_id(obj, ext->essent_name ?: ext->name, BTF_KIND_FUNC, &kern_btf, |
7810 | &mod_btf); | |
5bd022ec | 7811 | if (kfunc_id < 0) { |
466b2e13 KKD |
7812 | if (kfunc_id == -ESRCH && ext->is_weak) |
7813 | return 0; | |
7814 | pr_warn("extern (func ksym) '%s': not found in kernel or module BTFs\n", | |
5bd022ec MKL |
7815 | ext->name); |
7816 | return kfunc_id; | |
7817 | } | |
7818 | ||
5bd022ec MKL |
7819 | kern_func = btf__type_by_id(kern_btf, kfunc_id); |
7820 | kfunc_proto_id = kern_func->type; | |
7821 | ||
7822 | ret = bpf_core_types_are_compat(obj->btf, local_func_proto_id, | |
7823 | kern_btf, kfunc_proto_id); | |
7824 | if (ret <= 0) { | |
5964a223 DM |
7825 | if (ext->is_weak) |
7826 | return 0; | |
7827 | ||
f709160d AN |
7828 | pr_warn("extern (func ksym) '%s': func_proto [%d] incompatible with %s [%d]\n", |
7829 | ext->name, local_func_proto_id, | |
7830 | mod_btf ? mod_btf->name : "vmlinux", kfunc_proto_id); | |
5bd022ec MKL |
7831 | return -EINVAL; |
7832 | } | |
7833 | ||
9dbe6015 KKD |
7834 | /* set index for module BTF fd in fd_array, if unset */ |
7835 | if (mod_btf && !mod_btf->fd_array_idx) { | |
7836 | /* insn->off is s16 */ | |
7837 | if (obj->fd_array_cnt == INT16_MAX) { | |
7838 | pr_warn("extern (func ksym) '%s': module BTF fd index %d too big to fit in bpf_insn offset\n", | |
7839 | ext->name, mod_btf->fd_array_idx); | |
7840 | return -E2BIG; | |
7841 | } | |
7842 | /* Cannot use index 0 for module BTF fd */ | |
7843 | if (!obj->fd_array_cnt) | |
7844 | obj->fd_array_cnt = 1; | |
7845 | ||
7846 | ret = libbpf_ensure_mem((void **)&obj->fd_array, &obj->fd_array_cap, sizeof(int), | |
7847 | obj->fd_array_cnt + 1); | |
7848 | if (ret) | |
7849 | return ret; | |
7850 | mod_btf->fd_array_idx = obj->fd_array_cnt; | |
7851 | /* we assume module BTF FD is always >0 */ | |
7852 | obj->fd_array[obj->fd_array_cnt++] = mod_btf->fd; | |
7853 | } | |
7854 | ||
5bd022ec | 7855 | ext->is_set = true; |
5bd022ec | 7856 | ext->ksym.kernel_btf_id = kfunc_id; |
9dbe6015 | 7857 | ext->ksym.btf_fd_idx = mod_btf ? mod_btf->fd_array_idx : 0; |
5fc13ad5 AS |
7858 | /* Also set kernel_btf_obj_fd to make sure that bpf_object__relocate_data() |
7859 | * populates FD into ld_imm64 insn when it's used to point to kfunc. | |
7860 | * {kernel_btf_id, btf_fd_idx} -> fixup bpf_call. | |
7861 | * {kernel_btf_id, kernel_btf_obj_fd} -> fixup ld_imm64. | |
7862 | */ | |
7863 | ext->ksym.kernel_btf_obj_fd = mod_btf ? mod_btf->fd : 0; | |
f709160d AN |
7864 | pr_debug("extern (func ksym) '%s': resolved to %s [%d]\n", |
7865 | ext->name, mod_btf ? mod_btf->name : "vmlinux", kfunc_id); | |
5bd022ec MKL |
7866 | |
7867 | return 0; | |
7868 | } | |
7869 | ||
933d1aa3 MKL |
7870 | static int bpf_object__resolve_ksyms_btf_id(struct bpf_object *obj) |
7871 | { | |
5bd022ec | 7872 | const struct btf_type *t; |
933d1aa3 MKL |
7873 | struct extern_desc *ext; |
7874 | int i, err; | |
7875 | ||
7876 | for (i = 0; i < obj->nr_extern; i++) { | |
7877 | ext = &obj->externs[i]; | |
7878 | if (ext->type != EXT_KSYM || !ext->ksym.type_id) | |
7879 | continue; | |
7880 | ||
67234743 AS |
7881 | if (obj->gen_loader) { |
7882 | ext->is_set = true; | |
7883 | ext->ksym.kernel_btf_obj_fd = 0; | |
7884 | ext->ksym.kernel_btf_id = 0; | |
7885 | continue; | |
7886 | } | |
5bd022ec MKL |
7887 | t = btf__type_by_id(obj->btf, ext->btf_id); |
7888 | if (btf_is_var(t)) | |
7889 | err = bpf_object__resolve_ksym_var_btf_id(obj, ext); | |
7890 | else | |
7891 | err = bpf_object__resolve_ksym_func_btf_id(obj, ext); | |
933d1aa3 MKL |
7892 | if (err) |
7893 | return err; | |
d370bbe1 HL |
7894 | } |
7895 | return 0; | |
7896 | } | |
7897 | ||
166750bc | 7898 | static int bpf_object__resolve_externs(struct bpf_object *obj, |
8601fd42 | 7899 | const char *extra_kconfig) |
166750bc | 7900 | { |
1c0c7074 | 7901 | bool need_config = false, need_kallsyms = false; |
d370bbe1 | 7902 | bool need_vmlinux_btf = false; |
166750bc | 7903 | struct extern_desc *ext; |
2e33efe3 | 7904 | void *kcfg_data = NULL; |
166750bc | 7905 | int err, i; |
166750bc AN |
7906 | |
7907 | if (obj->nr_extern == 0) | |
7908 | return 0; | |
7909 | ||
2e33efe3 AN |
7910 | if (obj->kconfig_map_idx >= 0) |
7911 | kcfg_data = obj->maps[obj->kconfig_map_idx].mmaped; | |
166750bc AN |
7912 | |
7913 | for (i = 0; i < obj->nr_extern; i++) { | |
7914 | ext = &obj->externs[i]; | |
7915 | ||
55d00c37 AN |
7916 | if (ext->type == EXT_KSYM) { |
7917 | if (ext->ksym.type_id) | |
7918 | need_vmlinux_btf = true; | |
7919 | else | |
7920 | need_kallsyms = true; | |
7921 | continue; | |
7922 | } else if (ext->type == EXT_KCFG) { | |
7923 | void *ext_ptr = kcfg_data + ext->kcfg.data_off; | |
7924 | __u64 value = 0; | |
166750bc | 7925 | |
55d00c37 AN |
7926 | /* Kconfig externs need actual /proc/config.gz */ |
7927 | if (str_has_pfx(ext->name, "CONFIG_")) { | |
7928 | need_config = true; | |
7929 | continue; | |
7930 | } | |
7931 | ||
7932 | /* Virtual kcfg externs are customly handled by libbpf */ | |
7933 | if (strcmp(ext->name, "LINUX_KERNEL_VERSION") == 0) { | |
7934 | value = get_kernel_version(); | |
7935 | if (!value) { | |
7936 | pr_warn("extern (kcfg) '%s': failed to get kernel version\n", ext->name); | |
7937 | return -EINVAL; | |
7938 | } | |
7939 | } else if (strcmp(ext->name, "LINUX_HAS_BPF_COOKIE") == 0) { | |
7940 | value = kernel_supports(obj, FEAT_BPF_COOKIE); | |
6f5d467d AN |
7941 | } else if (strcmp(ext->name, "LINUX_HAS_SYSCALL_WRAPPER") == 0) { |
7942 | value = kernel_supports(obj, FEAT_SYSCALL_WRAPPER); | |
55d00c37 AN |
7943 | } else if (!str_has_pfx(ext->name, "LINUX_") || !ext->is_weak) { |
7944 | /* Currently libbpf supports only CONFIG_ and LINUX_ prefixed | |
7945 | * __kconfig externs, where LINUX_ ones are virtual and filled out | |
7946 | * customly by libbpf (their values don't come from Kconfig). | |
7947 | * If LINUX_xxx variable is not recognized by libbpf, but is marked | |
7948 | * __weak, it defaults to zero value, just like for CONFIG_xxx | |
7949 | * externs. | |
7950 | */ | |
7951 | pr_warn("extern (kcfg) '%s': unrecognized virtual extern\n", ext->name); | |
166750bc AN |
7952 | return -EINVAL; |
7953 | } | |
55d00c37 AN |
7954 | |
7955 | err = set_kcfg_value_num(ext, ext_ptr, value); | |
166750bc AN |
7956 | if (err) |
7957 | return err; | |
55d00c37 AN |
7958 | pr_debug("extern (kcfg) '%s': set to 0x%llx\n", |
7959 | ext->name, (long long)value); | |
166750bc | 7960 | } else { |
55d00c37 | 7961 | pr_warn("extern '%s': unrecognized extern kind\n", ext->name); |
166750bc AN |
7962 | return -EINVAL; |
7963 | } | |
7964 | } | |
8601fd42 | 7965 | if (need_config && extra_kconfig) { |
2e33efe3 | 7966 | err = bpf_object__read_kconfig_mem(obj, extra_kconfig, kcfg_data); |
8601fd42 AN |
7967 | if (err) |
7968 | return -EINVAL; | |
7969 | need_config = false; | |
7970 | for (i = 0; i < obj->nr_extern; i++) { | |
7971 | ext = &obj->externs[i]; | |
2e33efe3 | 7972 | if (ext->type == EXT_KCFG && !ext->is_set) { |
8601fd42 AN |
7973 | need_config = true; |
7974 | break; | |
7975 | } | |
7976 | } | |
7977 | } | |
166750bc | 7978 | if (need_config) { |
2e33efe3 | 7979 | err = bpf_object__read_kconfig_file(obj, kcfg_data); |
166750bc AN |
7980 | if (err) |
7981 | return -EINVAL; | |
7982 | } | |
1c0c7074 AN |
7983 | if (need_kallsyms) { |
7984 | err = bpf_object__read_kallsyms_file(obj); | |
7985 | if (err) | |
7986 | return -EINVAL; | |
7987 | } | |
d370bbe1 HL |
7988 | if (need_vmlinux_btf) { |
7989 | err = bpf_object__resolve_ksyms_btf_id(obj); | |
7990 | if (err) | |
7991 | return -EINVAL; | |
7992 | } | |
166750bc AN |
7993 | for (i = 0; i < obj->nr_extern; i++) { |
7994 | ext = &obj->externs[i]; | |
7995 | ||
7996 | if (!ext->is_set && !ext->is_weak) { | |
55d00c37 | 7997 | pr_warn("extern '%s' (strong): not resolved\n", ext->name); |
166750bc AN |
7998 | return -ESRCH; |
7999 | } else if (!ext->is_set) { | |
55d00c37 | 8000 | pr_debug("extern '%s' (weak): not resolved, defaulting to zero\n", |
166750bc AN |
8001 | ext->name); |
8002 | } | |
8003 | } | |
8004 | ||
8005 | return 0; | |
8006 | } | |
8007 | ||
8d1608d7 KFL |
8008 | static void bpf_map_prepare_vdata(const struct bpf_map *map) |
8009 | { | |
8010 | struct bpf_struct_ops *st_ops; | |
8011 | __u32 i; | |
8012 | ||
8013 | st_ops = map->st_ops; | |
8014 | for (i = 0; i < btf_vlen(st_ops->type); i++) { | |
8015 | struct bpf_program *prog = st_ops->progs[i]; | |
8016 | void *kern_data; | |
8017 | int prog_fd; | |
8018 | ||
8019 | if (!prog) | |
8020 | continue; | |
8021 | ||
8022 | prog_fd = bpf_program__fd(prog); | |
8023 | kern_data = st_ops->kern_vdata + st_ops->kern_func_off[i]; | |
8024 | *(unsigned long *)kern_data = prog_fd; | |
8025 | } | |
8026 | } | |
8027 | ||
8028 | static int bpf_object_prepare_struct_ops(struct bpf_object *obj) | |
8029 | { | |
8030 | int i; | |
8031 | ||
8032 | for (i = 0; i < obj->nr_maps; i++) | |
8033 | if (bpf_map__is_struct_ops(&obj->maps[i])) | |
8034 | bpf_map_prepare_vdata(&obj->maps[i]); | |
8035 | ||
8036 | return 0; | |
8037 | } | |
8038 | ||
e7b924ca | 8039 | static int bpf_object_load(struct bpf_object *obj, int extra_log_level, const char *target_btf_path) |
52d3352e | 8040 | { |
ec6d5f47 | 8041 | int err, i; |
6371ca3b | 8042 | |
52d3352e | 8043 | if (!obj) |
e9fc3ce9 | 8044 | return libbpf_err(-EINVAL); |
52d3352e WN |
8045 | |
8046 | if (obj->loaded) { | |
d9297581 | 8047 | pr_warn("object '%s': load can't be attempted twice\n", obj->name); |
e9fc3ce9 | 8048 | return libbpf_err(-EINVAL); |
52d3352e WN |
8049 | } |
8050 | ||
67234743 | 8051 | if (obj->gen_loader) |
be315829 | 8052 | bpf_gen__init(obj->gen_loader, extra_log_level, obj->nr_programs, obj->nr_maps); |
67234743 | 8053 | |
fd9eef1a | 8054 | err = bpf_object__probe_loading(obj); |
fe62de31 | 8055 | err = err ? : bpf_object__load_vmlinux_btf(obj, false); |
8601fd42 | 8056 | err = err ? : bpf_object__resolve_externs(obj, obj->kconfig); |
0d13bfce AN |
8057 | err = err ? : bpf_object__sanitize_and_load_btf(obj); |
8058 | err = err ? : bpf_object__sanitize_maps(obj); | |
590a0088 | 8059 | err = err ? : bpf_object__init_kern_struct_ops_maps(obj); |
0d13bfce | 8060 | err = err ? : bpf_object__create_maps(obj); |
e7b924ca AN |
8061 | err = err ? : bpf_object__relocate(obj, obj->btf_custom_path ? : target_btf_path); |
8062 | err = err ? : bpf_object__load_progs(obj, extra_log_level); | |
341ac5ff | 8063 | err = err ? : bpf_object_init_prog_arrays(obj); |
8d1608d7 | 8064 | err = err ? : bpf_object_prepare_struct_ops(obj); |
a6ed02ca | 8065 | |
67234743 AS |
8066 | if (obj->gen_loader) { |
8067 | /* reset FDs */ | |
4729445b KKD |
8068 | if (obj->btf) |
8069 | btf__set_fd(obj->btf, -1); | |
67234743 AS |
8070 | for (i = 0; i < obj->nr_maps; i++) |
8071 | obj->maps[i].fd = -1; | |
8072 | if (!err) | |
ba05fd36 | 8073 | err = bpf_gen__finish(obj->gen_loader, obj->nr_programs, obj->nr_maps); |
67234743 AS |
8074 | } |
8075 | ||
9dbe6015 KKD |
8076 | /* clean up fd_array */ |
8077 | zfree(&obj->fd_array); | |
8078 | ||
4f33a53d AN |
8079 | /* clean up module BTFs */ |
8080 | for (i = 0; i < obj->btf_module_cnt; i++) { | |
91abb4a6 | 8081 | close(obj->btf_modules[i].fd); |
4f33a53d AN |
8082 | btf__free(obj->btf_modules[i].btf); |
8083 | free(obj->btf_modules[i].name); | |
8084 | } | |
8085 | free(obj->btf_modules); | |
8086 | ||
8087 | /* clean up vmlinux BTF */ | |
a6ed02ca KS |
8088 | btf__free(obj->btf_vmlinux); |
8089 | obj->btf_vmlinux = NULL; | |
8090 | ||
d9297581 AN |
8091 | obj->loaded = true; /* doesn't matter if successfully or not */ |
8092 | ||
0d13bfce AN |
8093 | if (err) |
8094 | goto out; | |
52d3352e WN |
8095 | |
8096 | return 0; | |
8097 | out: | |
ec6d5f47 THJ |
8098 | /* unpin any maps that were auto-pinned during load */ |
8099 | for (i = 0; i < obj->nr_maps; i++) | |
8100 | if (obj->maps[i].pinned && !obj->maps[i].reused) | |
8101 | bpf_map__unpin(&obj->maps[i], NULL); | |
8102 | ||
4a404a7e | 8103 | bpf_object_unload(obj); |
be18010e | 8104 | pr_warn("failed to load object '%s'\n", obj->path); |
e9fc3ce9 | 8105 | return libbpf_err(err); |
52d3352e WN |
8106 | } |
8107 | ||
e7b924ca AN |
8108 | int bpf_object__load(struct bpf_object *obj) |
8109 | { | |
8110 | return bpf_object_load(obj, 0, NULL); | |
60276f98 QM |
8111 | } |
8112 | ||
196f8487 THJ |
8113 | static int make_parent_dir(const char *path) |
8114 | { | |
8115 | char *cp, errmsg[STRERR_BUFSIZE]; | |
8116 | char *dname, *dir; | |
8117 | int err = 0; | |
8118 | ||
8119 | dname = strdup(path); | |
8120 | if (dname == NULL) | |
8121 | return -ENOMEM; | |
8122 | ||
8123 | dir = dirname(dname); | |
8124 | if (mkdir(dir, 0700) && errno != EEXIST) | |
8125 | err = -errno; | |
8126 | ||
8127 | free(dname); | |
8128 | if (err) { | |
8129 | cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); | |
8130 | pr_warn("failed to mkdir %s: %s\n", path, cp); | |
8131 | } | |
8132 | return err; | |
8133 | } | |
8134 | ||
f367540c JS |
8135 | static int check_path(const char *path) |
8136 | { | |
1ce6a9fc | 8137 | char *cp, errmsg[STRERR_BUFSIZE]; |
f367540c JS |
8138 | struct statfs st_fs; |
8139 | char *dname, *dir; | |
8140 | int err = 0; | |
8141 | ||
8142 | if (path == NULL) | |
8143 | return -EINVAL; | |
8144 | ||
8145 | dname = strdup(path); | |
8146 | if (dname == NULL) | |
8147 | return -ENOMEM; | |
8148 | ||
8149 | dir = dirname(dname); | |
8150 | if (statfs(dir, &st_fs)) { | |
24d6a808 | 8151 | cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
be18010e | 8152 | pr_warn("failed to statfs %s: %s\n", dir, cp); |
f367540c JS |
8153 | err = -errno; |
8154 | } | |
8155 | free(dname); | |
8156 | ||
8157 | if (!err && st_fs.f_type != BPF_FS_MAGIC) { | |
be18010e | 8158 | pr_warn("specified path %s is not on BPF FS\n", path); |
f367540c JS |
8159 | err = -EINVAL; |
8160 | } | |
8161 | ||
8162 | return err; | |
8163 | } | |
8164 | ||
cf90a20d | 8165 | int bpf_program__pin(struct bpf_program *prog, const char *path) |
f367540c | 8166 | { |
1ce6a9fc | 8167 | char *cp, errmsg[STRERR_BUFSIZE]; |
f367540c JS |
8168 | int err; |
8169 | ||
cf90a20d AN |
8170 | if (prog->fd < 0) { |
8171 | pr_warn("prog '%s': can't pin program that wasn't loaded\n", prog->name); | |
8172 | return libbpf_err(-EINVAL); | |
8173 | } | |
8174 | ||
196f8487 THJ |
8175 | err = make_parent_dir(path); |
8176 | if (err) | |
e9fc3ce9 | 8177 | return libbpf_err(err); |
196f8487 | 8178 | |
f367540c JS |
8179 | err = check_path(path); |
8180 | if (err) | |
e9fc3ce9 | 8181 | return libbpf_err(err); |
f367540c | 8182 | |
cf90a20d | 8183 | if (bpf_obj_pin(prog->fd, path)) { |
23ab656b THJ |
8184 | err = -errno; |
8185 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
cf90a20d | 8186 | pr_warn("prog '%s': failed to pin at '%s': %s\n", prog->name, path, cp); |
e9fc3ce9 | 8187 | return libbpf_err(err); |
f367540c | 8188 | } |
f367540c | 8189 | |
cf90a20d | 8190 | pr_debug("prog '%s': pinned at '%s'\n", prog->name, path); |
f367540c JS |
8191 | return 0; |
8192 | } | |
8193 | ||
cf90a20d | 8194 | int bpf_program__unpin(struct bpf_program *prog, const char *path) |
0c19a9fb SF |
8195 | { |
8196 | int err; | |
8197 | ||
cf90a20d AN |
8198 | if (prog->fd < 0) { |
8199 | pr_warn("prog '%s': can't unpin program that wasn't loaded\n", prog->name); | |
e9fc3ce9 | 8200 | return libbpf_err(-EINVAL); |
0c19a9fb SF |
8201 | } |
8202 | ||
f367540c JS |
8203 | err = check_path(path); |
8204 | if (err) | |
e9fc3ce9 | 8205 | return libbpf_err(err); |
f367540c | 8206 | |
cf90a20d | 8207 | err = unlink(path); |
0c19a9fb | 8208 | if (err) |
e9fc3ce9 | 8209 | return libbpf_err(-errno); |
0c19a9fb | 8210 | |
cf90a20d | 8211 | pr_debug("prog '%s': unpinned from '%s'\n", prog->name, path); |
f367540c JS |
8212 | return 0; |
8213 | } | |
8214 | ||
b6989f35 JS |
8215 | int bpf_map__pin(struct bpf_map *map, const char *path) |
8216 | { | |
1ce6a9fc | 8217 | char *cp, errmsg[STRERR_BUFSIZE]; |
b6989f35 JS |
8218 | int err; |
8219 | ||
b6989f35 | 8220 | if (map == NULL) { |
be18010e | 8221 | pr_warn("invalid map pointer\n"); |
e9fc3ce9 | 8222 | return libbpf_err(-EINVAL); |
b6989f35 JS |
8223 | } |
8224 | ||
4580b25f THJ |
8225 | if (map->pin_path) { |
8226 | if (path && strcmp(path, map->pin_path)) { | |
8227 | pr_warn("map '%s' already has pin path '%s' different from '%s'\n", | |
8228 | bpf_map__name(map), map->pin_path, path); | |
e9fc3ce9 | 8229 | return libbpf_err(-EINVAL); |
4580b25f THJ |
8230 | } else if (map->pinned) { |
8231 | pr_debug("map '%s' already pinned at '%s'; not re-pinning\n", | |
8232 | bpf_map__name(map), map->pin_path); | |
8233 | return 0; | |
8234 | } | |
8235 | } else { | |
8236 | if (!path) { | |
8237 | pr_warn("missing a path to pin map '%s' at\n", | |
8238 | bpf_map__name(map)); | |
e9fc3ce9 | 8239 | return libbpf_err(-EINVAL); |
4580b25f THJ |
8240 | } else if (map->pinned) { |
8241 | pr_warn("map '%s' already pinned\n", bpf_map__name(map)); | |
e9fc3ce9 | 8242 | return libbpf_err(-EEXIST); |
4580b25f THJ |
8243 | } |
8244 | ||
8245 | map->pin_path = strdup(path); | |
8246 | if (!map->pin_path) { | |
8247 | err = -errno; | |
8248 | goto out_err; | |
8249 | } | |
b6989f35 JS |
8250 | } |
8251 | ||
196f8487 THJ |
8252 | err = make_parent_dir(map->pin_path); |
8253 | if (err) | |
e9fc3ce9 | 8254 | return libbpf_err(err); |
196f8487 | 8255 | |
4580b25f THJ |
8256 | err = check_path(map->pin_path); |
8257 | if (err) | |
e9fc3ce9 | 8258 | return libbpf_err(err); |
4580b25f THJ |
8259 | |
8260 | if (bpf_obj_pin(map->fd, map->pin_path)) { | |
8261 | err = -errno; | |
8262 | goto out_err; | |
8263 | } | |
8264 | ||
8265 | map->pinned = true; | |
8266 | pr_debug("pinned map '%s'\n", map->pin_path); | |
0c19a9fb | 8267 | |
b6989f35 | 8268 | return 0; |
4580b25f THJ |
8269 | |
8270 | out_err: | |
8271 | cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); | |
8272 | pr_warn("failed to pin map: %s\n", cp); | |
e9fc3ce9 | 8273 | return libbpf_err(err); |
b6989f35 JS |
8274 | } |
8275 | ||
0c19a9fb SF |
8276 | int bpf_map__unpin(struct bpf_map *map, const char *path) |
8277 | { | |
8278 | int err; | |
8279 | ||
0c19a9fb | 8280 | if (map == NULL) { |
be18010e | 8281 | pr_warn("invalid map pointer\n"); |
e9fc3ce9 | 8282 | return libbpf_err(-EINVAL); |
0c19a9fb SF |
8283 | } |
8284 | ||
4580b25f THJ |
8285 | if (map->pin_path) { |
8286 | if (path && strcmp(path, map->pin_path)) { | |
8287 | pr_warn("map '%s' already has pin path '%s' different from '%s'\n", | |
8288 | bpf_map__name(map), map->pin_path, path); | |
e9fc3ce9 | 8289 | return libbpf_err(-EINVAL); |
4580b25f THJ |
8290 | } |
8291 | path = map->pin_path; | |
8292 | } else if (!path) { | |
8293 | pr_warn("no path to unpin map '%s' from\n", | |
8294 | bpf_map__name(map)); | |
e9fc3ce9 | 8295 | return libbpf_err(-EINVAL); |
4580b25f THJ |
8296 | } |
8297 | ||
8298 | err = check_path(path); | |
8299 | if (err) | |
e9fc3ce9 | 8300 | return libbpf_err(err); |
4580b25f | 8301 | |
0c19a9fb SF |
8302 | err = unlink(path); |
8303 | if (err != 0) | |
e9fc3ce9 | 8304 | return libbpf_err(-errno); |
4580b25f THJ |
8305 | |
8306 | map->pinned = false; | |
8307 | pr_debug("unpinned map '%s' from '%s'\n", bpf_map__name(map), path); | |
0c19a9fb SF |
8308 | |
8309 | return 0; | |
8310 | } | |
8311 | ||
4580b25f THJ |
8312 | int bpf_map__set_pin_path(struct bpf_map *map, const char *path) |
8313 | { | |
8314 | char *new = NULL; | |
8315 | ||
8316 | if (path) { | |
8317 | new = strdup(path); | |
8318 | if (!new) | |
e9fc3ce9 | 8319 | return libbpf_err(-errno); |
4580b25f THJ |
8320 | } |
8321 | ||
8322 | free(map->pin_path); | |
8323 | map->pin_path = new; | |
8324 | return 0; | |
8325 | } | |
8326 | ||
20eccf29 AN |
8327 | __alias(bpf_map__pin_path) |
8328 | const char *bpf_map__get_pin_path(const struct bpf_map *map); | |
4580b25f | 8329 | |
e244d34d EL |
8330 | const char *bpf_map__pin_path(const struct bpf_map *map) |
8331 | { | |
8332 | return map->pin_path; | |
8333 | } | |
8334 | ||
4580b25f THJ |
8335 | bool bpf_map__is_pinned(const struct bpf_map *map) |
8336 | { | |
8337 | return map->pinned; | |
8338 | } | |
8339 | ||
9cf309c5 THJ |
8340 | static void sanitize_pin_path(char *s) |
8341 | { | |
8342 | /* bpffs disallows periods in path names */ | |
8343 | while (*s) { | |
8344 | if (*s == '.') | |
8345 | *s = '_'; | |
8346 | s++; | |
8347 | } | |
8348 | } | |
8349 | ||
0c19a9fb | 8350 | int bpf_object__pin_maps(struct bpf_object *obj, const char *path) |
d5148d85 | 8351 | { |
d5148d85 JS |
8352 | struct bpf_map *map; |
8353 | int err; | |
8354 | ||
8355 | if (!obj) | |
e9fc3ce9 | 8356 | return libbpf_err(-ENOENT); |
d5148d85 JS |
8357 | |
8358 | if (!obj->loaded) { | |
be18010e | 8359 | pr_warn("object not yet loaded; load it first\n"); |
e9fc3ce9 | 8360 | return libbpf_err(-ENOENT); |
d5148d85 JS |
8361 | } |
8362 | ||
f74a53d9 | 8363 | bpf_object__for_each_map(map, obj) { |
4580b25f | 8364 | char *pin_path = NULL; |
0c19a9fb | 8365 | char buf[PATH_MAX]; |
0c19a9fb | 8366 | |
ec41817b | 8367 | if (!map->autocreate) |
229fae38 SC |
8368 | continue; |
8369 | ||
4580b25f | 8370 | if (path) { |
e588c116 WY |
8371 | err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map)); |
8372 | if (err) | |
4580b25f | 8373 | goto err_unpin_maps; |
9cf309c5 | 8374 | sanitize_pin_path(buf); |
4580b25f THJ |
8375 | pin_path = buf; |
8376 | } else if (!map->pin_path) { | |
8377 | continue; | |
0c19a9fb SF |
8378 | } |
8379 | ||
4580b25f | 8380 | err = bpf_map__pin(map, pin_path); |
0c19a9fb SF |
8381 | if (err) |
8382 | goto err_unpin_maps; | |
8383 | } | |
8384 | ||
8385 | return 0; | |
8386 | ||
8387 | err_unpin_maps: | |
bcc40fc0 | 8388 | while ((map = bpf_object__prev_map(obj, map))) { |
4580b25f | 8389 | if (!map->pin_path) |
0c19a9fb SF |
8390 | continue; |
8391 | ||
4580b25f | 8392 | bpf_map__unpin(map, NULL); |
0c19a9fb SF |
8393 | } |
8394 | ||
e9fc3ce9 | 8395 | return libbpf_err(err); |
0c19a9fb SF |
8396 | } |
8397 | ||
8398 | int bpf_object__unpin_maps(struct bpf_object *obj, const char *path) | |
8399 | { | |
8400 | struct bpf_map *map; | |
8401 | int err; | |
8402 | ||
8403 | if (!obj) | |
e9fc3ce9 | 8404 | return libbpf_err(-ENOENT); |
0c19a9fb | 8405 | |
f74a53d9 | 8406 | bpf_object__for_each_map(map, obj) { |
4580b25f | 8407 | char *pin_path = NULL; |
d5148d85 | 8408 | char buf[PATH_MAX]; |
d5148d85 | 8409 | |
4580b25f | 8410 | if (path) { |
e588c116 WY |
8411 | err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map)); |
8412 | if (err) | |
8413 | return libbpf_err(err); | |
9cf309c5 | 8414 | sanitize_pin_path(buf); |
4580b25f THJ |
8415 | pin_path = buf; |
8416 | } else if (!map->pin_path) { | |
8417 | continue; | |
8418 | } | |
d5148d85 | 8419 | |
4580b25f | 8420 | err = bpf_map__unpin(map, pin_path); |
d5148d85 | 8421 | if (err) |
e9fc3ce9 | 8422 | return libbpf_err(err); |
d5148d85 JS |
8423 | } |
8424 | ||
0c19a9fb SF |
8425 | return 0; |
8426 | } | |
8427 | ||
8428 | int bpf_object__pin_programs(struct bpf_object *obj, const char *path) | |
8429 | { | |
8430 | struct bpf_program *prog; | |
e588c116 | 8431 | char buf[PATH_MAX]; |
0c19a9fb SF |
8432 | int err; |
8433 | ||
8434 | if (!obj) | |
e9fc3ce9 | 8435 | return libbpf_err(-ENOENT); |
0c19a9fb SF |
8436 | |
8437 | if (!obj->loaded) { | |
be18010e | 8438 | pr_warn("object not yet loaded; load it first\n"); |
e9fc3ce9 | 8439 | return libbpf_err(-ENOENT); |
0c19a9fb SF |
8440 | } |
8441 | ||
0c19a9fb | 8442 | bpf_object__for_each_program(prog, obj) { |
e588c116 WY |
8443 | err = pathname_concat(buf, sizeof(buf), path, prog->name); |
8444 | if (err) | |
0c19a9fb | 8445 | goto err_unpin_programs; |
0c19a9fb SF |
8446 | |
8447 | err = bpf_program__pin(prog, buf); | |
8448 | if (err) | |
8449 | goto err_unpin_programs; | |
8450 | } | |
8451 | ||
8452 | return 0; | |
8453 | ||
8454 | err_unpin_programs: | |
bcc40fc0 | 8455 | while ((prog = bpf_object__prev_program(obj, prog))) { |
e588c116 | 8456 | if (pathname_concat(buf, sizeof(buf), path, prog->name)) |
0c19a9fb SF |
8457 | continue; |
8458 | ||
8459 | bpf_program__unpin(prog, buf); | |
8460 | } | |
8461 | ||
e9fc3ce9 | 8462 | return libbpf_err(err); |
0c19a9fb SF |
8463 | } |
8464 | ||
8465 | int bpf_object__unpin_programs(struct bpf_object *obj, const char *path) | |
8466 | { | |
8467 | struct bpf_program *prog; | |
8468 | int err; | |
8469 | ||
8470 | if (!obj) | |
e9fc3ce9 | 8471 | return libbpf_err(-ENOENT); |
0c19a9fb | 8472 | |
d5148d85 JS |
8473 | bpf_object__for_each_program(prog, obj) { |
8474 | char buf[PATH_MAX]; | |
d5148d85 | 8475 | |
e588c116 WY |
8476 | err = pathname_concat(buf, sizeof(buf), path, prog->name); |
8477 | if (err) | |
8478 | return libbpf_err(err); | |
d5148d85 | 8479 | |
0c19a9fb | 8480 | err = bpf_program__unpin(prog, buf); |
d5148d85 | 8481 | if (err) |
e9fc3ce9 | 8482 | return libbpf_err(err); |
d5148d85 JS |
8483 | } |
8484 | ||
8485 | return 0; | |
8486 | } | |
8487 | ||
0c19a9fb SF |
8488 | int bpf_object__pin(struct bpf_object *obj, const char *path) |
8489 | { | |
8490 | int err; | |
8491 | ||
8492 | err = bpf_object__pin_maps(obj, path); | |
8493 | if (err) | |
e9fc3ce9 | 8494 | return libbpf_err(err); |
0c19a9fb SF |
8495 | |
8496 | err = bpf_object__pin_programs(obj, path); | |
8497 | if (err) { | |
8498 | bpf_object__unpin_maps(obj, path); | |
e9fc3ce9 | 8499 | return libbpf_err(err); |
0c19a9fb SF |
8500 | } |
8501 | ||
8502 | return 0; | |
8503 | } | |
8504 | ||
068ca522 DX |
8505 | int bpf_object__unpin(struct bpf_object *obj, const char *path) |
8506 | { | |
8507 | int err; | |
8508 | ||
8509 | err = bpf_object__unpin_programs(obj, path); | |
8510 | if (err) | |
8511 | return libbpf_err(err); | |
8512 | ||
8513 | err = bpf_object__unpin_maps(obj, path); | |
8514 | if (err) | |
8515 | return libbpf_err(err); | |
8516 | ||
8517 | return 0; | |
8518 | } | |
8519 | ||
2d39d7c5 AN |
8520 | static void bpf_map__destroy(struct bpf_map *map) |
8521 | { | |
646f02ff AN |
8522 | if (map->inner_map) { |
8523 | bpf_map__destroy(map->inner_map); | |
8524 | zfree(&map->inner_map); | |
8525 | } | |
8526 | ||
8527 | zfree(&map->init_slots); | |
8528 | map->init_slots_sz = 0; | |
8529 | ||
2d39d7c5 | 8530 | if (map->mmaped) { |
9d0a2331 JK |
8531 | size_t mmap_sz; |
8532 | ||
8533 | mmap_sz = bpf_map_mmap_sz(map->def.value_size, map->def.max_entries); | |
8534 | munmap(map->mmaped, mmap_sz); | |
2d39d7c5 AN |
8535 | map->mmaped = NULL; |
8536 | } | |
8537 | ||
8538 | if (map->st_ops) { | |
8539 | zfree(&map->st_ops->data); | |
8540 | zfree(&map->st_ops->progs); | |
8541 | zfree(&map->st_ops->kern_func_off); | |
8542 | zfree(&map->st_ops); | |
8543 | } | |
8544 | ||
8545 | zfree(&map->name); | |
aed65917 | 8546 | zfree(&map->real_name); |
2d39d7c5 AN |
8547 | zfree(&map->pin_path); |
8548 | ||
8549 | if (map->fd >= 0) | |
8550 | zclose(map->fd); | |
8551 | } | |
8552 | ||
1a5e3fb1 WN |
8553 | void bpf_object__close(struct bpf_object *obj) |
8554 | { | |
a5b8bd47 WN |
8555 | size_t i; |
8556 | ||
50450fc7 | 8557 | if (IS_ERR_OR_NULL(obj)) |
1a5e3fb1 WN |
8558 | return; |
8559 | ||
2e4913e0 AN |
8560 | usdt_manager_free(obj->usdt_man); |
8561 | obj->usdt_man = NULL; | |
8562 | ||
67234743 | 8563 | bpf_gen__free(obj->gen_loader); |
1a5e3fb1 | 8564 | bpf_object__elf_finish(obj); |
4a404a7e | 8565 | bpf_object_unload(obj); |
8a138aed | 8566 | btf__free(obj->btf); |
29d67fde | 8567 | btf__free(obj->btf_vmlinux); |
2993e051 | 8568 | btf_ext__free(obj->btf_ext); |
1a5e3fb1 | 8569 | |
2d39d7c5 AN |
8570 | for (i = 0; i < obj->nr_maps; i++) |
8571 | bpf_map__destroy(&obj->maps[i]); | |
d859900c | 8572 | |
1373ff59 | 8573 | zfree(&obj->btf_custom_path); |
8601fd42 | 8574 | zfree(&obj->kconfig); |
5964a223 DM |
8575 | |
8576 | for (i = 0; i < obj->nr_extern; i++) | |
8577 | zfree(&obj->externs[i].essent_name); | |
8578 | ||
166750bc AN |
8579 | zfree(&obj->externs); |
8580 | obj->nr_extern = 0; | |
8581 | ||
9d759a9b WN |
8582 | zfree(&obj->maps); |
8583 | obj->nr_maps = 0; | |
a5b8bd47 WN |
8584 | |
8585 | if (obj->programs && obj->nr_programs) { | |
8586 | for (i = 0; i < obj->nr_programs; i++) | |
8587 | bpf_program__exit(&obj->programs[i]); | |
8588 | } | |
8589 | zfree(&obj->programs); | |
8590 | ||
1a5e3fb1 WN |
8591 | free(obj); |
8592 | } | |
aa9b1ac3 | 8593 | |
a324aae3 | 8594 | const char *bpf_object__name(const struct bpf_object *obj) |
acf860ae | 8595 | { |
e9fc3ce9 | 8596 | return obj ? obj->name : libbpf_err_ptr(-EINVAL); |
acf860ae WN |
8597 | } |
8598 | ||
a324aae3 | 8599 | unsigned int bpf_object__kversion(const struct bpf_object *obj) |
45825d8a | 8600 | { |
a7fe0450 | 8601 | return obj ? obj->kern_version : 0; |
45825d8a WN |
8602 | } |
8603 | ||
a324aae3 | 8604 | struct btf *bpf_object__btf(const struct bpf_object *obj) |
789f6bab AI |
8605 | { |
8606 | return obj ? obj->btf : NULL; | |
8607 | } | |
8608 | ||
8a138aed MKL |
8609 | int bpf_object__btf_fd(const struct bpf_object *obj) |
8610 | { | |
8611 | return obj->btf ? btf__fd(obj->btf) : -1; | |
8612 | } | |
8613 | ||
155f556d RDT |
8614 | int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version) |
8615 | { | |
8616 | if (obj->loaded) | |
e9fc3ce9 | 8617 | return libbpf_err(-EINVAL); |
155f556d RDT |
8618 | |
8619 | obj->kern_version = kern_version; | |
8620 | ||
8621 | return 0; | |
8622 | } | |
8623 | ||
67234743 AS |
8624 | int bpf_object__gen_loader(struct bpf_object *obj, struct gen_loader_opts *opts) |
8625 | { | |
8626 | struct bpf_gen *gen; | |
8627 | ||
8628 | if (!opts) | |
8629 | return -EFAULT; | |
8630 | if (!OPTS_VALID(opts, gen_loader_opts)) | |
8631 | return -EINVAL; | |
8632 | gen = calloc(sizeof(*gen), 1); | |
8633 | if (!gen) | |
8634 | return -ENOMEM; | |
8635 | gen->opts = opts; | |
8636 | obj->gen_loader = gen; | |
8637 | return 0; | |
8638 | } | |
8639 | ||
eac7d845 | 8640 | static struct bpf_program * |
a324aae3 AN |
8641 | __bpf_program__iter(const struct bpf_program *p, const struct bpf_object *obj, |
8642 | bool forward) | |
aa9b1ac3 | 8643 | { |
a83d6e76 | 8644 | size_t nr_programs = obj->nr_programs; |
0c19a9fb | 8645 | ssize_t idx; |
aa9b1ac3 | 8646 | |
a83d6e76 | 8647 | if (!nr_programs) |
aa9b1ac3 | 8648 | return NULL; |
aa9b1ac3 | 8649 | |
a83d6e76 MKL |
8650 | if (!p) |
8651 | /* Iter from the beginning */ | |
8652 | return forward ? &obj->programs[0] : | |
8653 | &obj->programs[nr_programs - 1]; | |
8654 | ||
0c19a9fb | 8655 | if (p->obj != obj) { |
be18010e | 8656 | pr_warn("error: program handler doesn't match object\n"); |
e9fc3ce9 | 8657 | return errno = EINVAL, NULL; |
aa9b1ac3 WN |
8658 | } |
8659 | ||
a83d6e76 | 8660 | idx = (p - obj->programs) + (forward ? 1 : -1); |
0c19a9fb | 8661 | if (idx >= obj->nr_programs || idx < 0) |
aa9b1ac3 WN |
8662 | return NULL; |
8663 | return &obj->programs[idx]; | |
8664 | } | |
8665 | ||
2088a3a7 HC |
8666 | struct bpf_program * |
8667 | bpf_object__next_program(const struct bpf_object *obj, struct bpf_program *prev) | |
eac7d845 JK |
8668 | { |
8669 | struct bpf_program *prog = prev; | |
8670 | ||
8671 | do { | |
a83d6e76 | 8672 | prog = __bpf_program__iter(prog, obj, true); |
c3c55696 | 8673 | } while (prog && prog_is_subprog(obj, prog)); |
0c19a9fb SF |
8674 | |
8675 | return prog; | |
8676 | } | |
8677 | ||
2088a3a7 HC |
8678 | struct bpf_program * |
8679 | bpf_object__prev_program(const struct bpf_object *obj, struct bpf_program *next) | |
0c19a9fb SF |
8680 | { |
8681 | struct bpf_program *prog = next; | |
8682 | ||
0c19a9fb | 8683 | do { |
a83d6e76 | 8684 | prog = __bpf_program__iter(prog, obj, false); |
c3c55696 | 8685 | } while (prog && prog_is_subprog(obj, prog)); |
eac7d845 JK |
8686 | |
8687 | return prog; | |
8688 | } | |
8689 | ||
9aba3613 JK |
8690 | void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex) |
8691 | { | |
8692 | prog->prog_ifindex = ifindex; | |
8693 | } | |
8694 | ||
01af3bf0 AN |
8695 | const char *bpf_program__name(const struct bpf_program *prog) |
8696 | { | |
8697 | return prog->name; | |
8698 | } | |
8699 | ||
52109584 AN |
8700 | const char *bpf_program__section_name(const struct bpf_program *prog) |
8701 | { | |
8702 | return prog->sec_name; | |
8703 | } | |
8704 | ||
d9297581 AN |
8705 | bool bpf_program__autoload(const struct bpf_program *prog) |
8706 | { | |
a3820c48 | 8707 | return prog->autoload; |
d9297581 AN |
8708 | } |
8709 | ||
8710 | int bpf_program__set_autoload(struct bpf_program *prog, bool autoload) | |
8711 | { | |
8712 | if (prog->obj->loaded) | |
e9fc3ce9 | 8713 | return libbpf_err(-EINVAL); |
d9297581 | 8714 | |
a3820c48 | 8715 | prog->autoload = autoload; |
d9297581 AN |
8716 | return 0; |
8717 | } | |
8718 | ||
43cb8cba HL |
8719 | bool bpf_program__autoattach(const struct bpf_program *prog) |
8720 | { | |
8721 | return prog->autoattach; | |
8722 | } | |
8723 | ||
8724 | void bpf_program__set_autoattach(struct bpf_program *prog, bool autoattach) | |
8725 | { | |
8726 | prog->autoattach = autoattach; | |
8727 | } | |
8728 | ||
65a7fa2e AN |
8729 | const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog) |
8730 | { | |
8731 | return prog->insns; | |
8732 | } | |
8733 | ||
8734 | size_t bpf_program__insn_cnt(const struct bpf_program *prog) | |
8735 | { | |
8736 | return prog->insns_cnt; | |
8737 | } | |
8738 | ||
b63b3c49 JO |
8739 | int bpf_program__set_insns(struct bpf_program *prog, |
8740 | struct bpf_insn *new_insns, size_t new_insn_cnt) | |
8741 | { | |
8742 | struct bpf_insn *insns; | |
8743 | ||
8744 | if (prog->obj->loaded) | |
8745 | return -EBUSY; | |
8746 | ||
8747 | insns = libbpf_reallocarray(prog->insns, new_insn_cnt, sizeof(*insns)); | |
8a0260db AN |
8748 | /* NULL is a valid return from reallocarray if the new count is zero */ |
8749 | if (!insns && new_insn_cnt) { | |
b63b3c49 JO |
8750 | pr_warn("prog '%s': failed to realloc prog code\n", prog->name); |
8751 | return -ENOMEM; | |
8752 | } | |
8753 | memcpy(insns, new_insns, new_insn_cnt * sizeof(*insns)); | |
8754 | ||
8755 | prog->insns = insns; | |
8756 | prog->insns_cnt = new_insn_cnt; | |
8757 | return 0; | |
8758 | } | |
8759 | ||
cf90a20d | 8760 | int bpf_program__fd(const struct bpf_program *prog) |
b580563e | 8761 | { |
1e960043 | 8762 | if (!prog) |
e9fc3ce9 | 8763 | return libbpf_err(-EINVAL); |
1e960043 | 8764 | |
cf90a20d | 8765 | if (prog->fd < 0) |
e9fc3ce9 | 8766 | return libbpf_err(-ENOENT); |
b580563e | 8767 | |
cf90a20d | 8768 | return prog->fd; |
aa9b1ac3 | 8769 | } |
9d759a9b | 8770 | |
20eccf29 AN |
8771 | __alias(bpf_program__type) |
8772 | enum bpf_prog_type bpf_program__get_type(const struct bpf_program *prog); | |
8773 | ||
8774 | enum bpf_prog_type bpf_program__type(const struct bpf_program *prog) | |
f1eead9e AN |
8775 | { |
8776 | return prog->type; | |
8777 | } | |
8778 | ||
c628747c AN |
8779 | static size_t custom_sec_def_cnt; |
8780 | static struct bpf_sec_def *custom_sec_defs; | |
8781 | static struct bpf_sec_def custom_fallback_def; | |
8782 | static bool has_custom_fallback_def; | |
8783 | static int last_custom_sec_def_handler_id; | |
8784 | ||
93442f13 | 8785 | int bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type) |
5f44e4c8 | 8786 | { |
93442f13 GS |
8787 | if (prog->obj->loaded) |
8788 | return libbpf_err(-EBUSY); | |
8789 | ||
c628747c AN |
8790 | /* if type is not changed, do nothing */ |
8791 | if (prog->type == type) | |
8792 | return 0; | |
8793 | ||
5f44e4c8 | 8794 | prog->type = type; |
c628747c AN |
8795 | |
8796 | /* If a program type was changed, we need to reset associated SEC() | |
8797 | * handler, as it will be invalid now. The only exception is a generic | |
8798 | * fallback handler, which by definition is program type-agnostic and | |
8799 | * is a catch-all custom handler, optionally set by the application, | |
8800 | * so should be able to handle any type of BPF program. | |
8801 | */ | |
8802 | if (prog->sec_def != &custom_fallback_def) | |
8803 | prog->sec_def = NULL; | |
93442f13 | 8804 | return 0; |
5f44e4c8 WN |
8805 | } |
8806 | ||
20eccf29 AN |
8807 | __alias(bpf_program__expected_attach_type) |
8808 | enum bpf_attach_type bpf_program__get_expected_attach_type(const struct bpf_program *prog); | |
8809 | ||
8810 | enum bpf_attach_type bpf_program__expected_attach_type(const struct bpf_program *prog) | |
f1eead9e AN |
8811 | { |
8812 | return prog->expected_attach_type; | |
8813 | } | |
8814 | ||
93442f13 | 8815 | int bpf_program__set_expected_attach_type(struct bpf_program *prog, |
16962b24 | 8816 | enum bpf_attach_type type) |
d7be143b | 8817 | { |
93442f13 GS |
8818 | if (prog->obj->loaded) |
8819 | return libbpf_err(-EBUSY); | |
8820 | ||
d7be143b | 8821 | prog->expected_attach_type = type; |
93442f13 | 8822 | return 0; |
d7be143b AI |
8823 | } |
8824 | ||
a6ca7158 AN |
8825 | __u32 bpf_program__flags(const struct bpf_program *prog) |
8826 | { | |
8827 | return prog->prog_flags; | |
8828 | } | |
8829 | ||
8cccee9e | 8830 | int bpf_program__set_flags(struct bpf_program *prog, __u32 flags) |
a6ca7158 AN |
8831 | { |
8832 | if (prog->obj->loaded) | |
8833 | return libbpf_err(-EBUSY); | |
8834 | ||
8cccee9e | 8835 | prog->prog_flags = flags; |
a6ca7158 AN |
8836 | return 0; |
8837 | } | |
8838 | ||
dbdd2c7f AN |
8839 | __u32 bpf_program__log_level(const struct bpf_program *prog) |
8840 | { | |
8841 | return prog->log_level; | |
8842 | } | |
8843 | ||
8844 | int bpf_program__set_log_level(struct bpf_program *prog, __u32 log_level) | |
8845 | { | |
8846 | if (prog->obj->loaded) | |
8847 | return libbpf_err(-EBUSY); | |
8848 | ||
8849 | prog->log_level = log_level; | |
8850 | return 0; | |
8851 | } | |
8852 | ||
b3ce9079 AN |
8853 | const char *bpf_program__log_buf(const struct bpf_program *prog, size_t *log_size) |
8854 | { | |
8855 | *log_size = prog->log_size; | |
8856 | return prog->log_buf; | |
8857 | } | |
8858 | ||
8859 | int bpf_program__set_log_buf(struct bpf_program *prog, char *log_buf, size_t log_size) | |
8860 | { | |
8861 | if (log_size && !log_buf) | |
8862 | return -EINVAL; | |
8863 | if (prog->log_size > UINT_MAX) | |
8864 | return -EINVAL; | |
8865 | if (prog->obj->loaded) | |
8866 | return -EBUSY; | |
8867 | ||
8868 | prog->log_buf = log_buf; | |
8869 | prog->log_size = log_size; | |
a6ca7158 AN |
8870 | return 0; |
8871 | } | |
8872 | ||
15ea31fa | 8873 | #define SEC_DEF(sec_pfx, ptype, atype, flags, ...) { \ |
697f104d | 8874 | .sec = (char *)sec_pfx, \ |
d7a18ea7 | 8875 | .prog_type = BPF_PROG_TYPE_##ptype, \ |
15ea31fa AN |
8876 | .expected_attach_type = atype, \ |
8877 | .cookie = (long)(flags), \ | |
4fa5bcfe | 8878 | .prog_prepare_load_fn = libbpf_prepare_prog_load, \ |
d7a18ea7 AN |
8879 | __VA_ARGS__ \ |
8880 | } | |
8881 | ||
4fa5bcfe | 8882 | static int attach_kprobe(const struct bpf_program *prog, long cookie, struct bpf_link **link); |
39f8dc43 | 8883 | static int attach_uprobe(const struct bpf_program *prog, long cookie, struct bpf_link **link); |
708ac5be | 8884 | static int attach_ksyscall(const struct bpf_program *prog, long cookie, struct bpf_link **link); |
2e4913e0 | 8885 | static int attach_usdt(const struct bpf_program *prog, long cookie, struct bpf_link **link); |
4fa5bcfe AN |
8886 | static int attach_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link); |
8887 | static int attach_raw_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link); | |
8888 | static int attach_trace(const struct bpf_program *prog, long cookie, struct bpf_link **link); | |
ddc6b049 | 8889 | static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link); |
5bfdd32d | 8890 | static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link); |
4fa5bcfe AN |
8891 | static int attach_lsm(const struct bpf_program *prog, long cookie, struct bpf_link **link); |
8892 | static int attach_iter(const struct bpf_program *prog, long cookie, struct bpf_link **link); | |
d7a18ea7 | 8893 | |
d7a18ea7 | 8894 | static const struct bpf_sec_def section_defs[] = { |
450b167f AN |
8895 | SEC_DEF("socket", SOCKET_FILTER, 0, SEC_NONE), |
8896 | SEC_DEF("sk_reuseport/migrate", SK_REUSEPORT, BPF_SK_REUSEPORT_SELECT_OR_MIGRATE, SEC_ATTACHABLE), | |
8897 | SEC_DEF("sk_reuseport", SK_REUSEPORT, BPF_SK_REUSEPORT_SELECT, SEC_ATTACHABLE), | |
9af8efc4 | 8898 | SEC_DEF("kprobe+", KPROBE, 0, SEC_NONE, attach_kprobe), |
39f8dc43 | 8899 | SEC_DEF("uprobe+", KPROBE, 0, SEC_NONE, attach_uprobe), |
c4cac71f | 8900 | SEC_DEF("uprobe.s+", KPROBE, 0, SEC_SLEEPABLE, attach_uprobe), |
9af8efc4 | 8901 | SEC_DEF("kretprobe+", KPROBE, 0, SEC_NONE, attach_kprobe), |
39f8dc43 | 8902 | SEC_DEF("uretprobe+", KPROBE, 0, SEC_NONE, attach_uprobe), |
c4cac71f | 8903 | SEC_DEF("uretprobe.s+", KPROBE, 0, SEC_SLEEPABLE, attach_uprobe), |
9af8efc4 AN |
8904 | SEC_DEF("kprobe.multi+", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi), |
8905 | SEC_DEF("kretprobe.multi+", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi), | |
5bfdd32d JO |
8906 | SEC_DEF("uprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi), |
8907 | SEC_DEF("uretprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi), | |
8908 | SEC_DEF("uprobe.multi.s+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_SLEEPABLE, attach_uprobe_multi), | |
8909 | SEC_DEF("uretprobe.multi.s+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_SLEEPABLE, attach_uprobe_multi), | |
708ac5be AN |
8910 | SEC_DEF("ksyscall+", KPROBE, 0, SEC_NONE, attach_ksyscall), |
8911 | SEC_DEF("kretsyscall+", KPROBE, 0, SEC_NONE, attach_ksyscall), | |
5902da6d JO |
8912 | SEC_DEF("usdt+", KPROBE, 0, SEC_USDT, attach_usdt), |
8913 | SEC_DEF("usdt.s+", KPROBE, 0, SEC_USDT | SEC_SLEEPABLE, attach_usdt), | |
fe20ce3a DB |
8914 | SEC_DEF("tc/ingress", SCHED_CLS, BPF_TCX_INGRESS, SEC_NONE), /* alias for tcx */ |
8915 | SEC_DEF("tc/egress", SCHED_CLS, BPF_TCX_EGRESS, SEC_NONE), /* alias for tcx */ | |
8916 | SEC_DEF("tcx/ingress", SCHED_CLS, BPF_TCX_INGRESS, SEC_NONE), | |
8917 | SEC_DEF("tcx/egress", SCHED_CLS, BPF_TCX_EGRESS, SEC_NONE), | |
8918 | SEC_DEF("tc", SCHED_CLS, 0, SEC_NONE), /* deprecated / legacy, use tcx */ | |
8919 | SEC_DEF("classifier", SCHED_CLS, 0, SEC_NONE), /* deprecated / legacy, use tcx */ | |
8920 | SEC_DEF("action", SCHED_ACT, 0, SEC_NONE), /* deprecated / legacy, use tcx */ | |
05c31b4a DB |
8921 | SEC_DEF("netkit/primary", SCHED_CLS, BPF_NETKIT_PRIMARY, SEC_NONE), |
8922 | SEC_DEF("netkit/peer", SCHED_CLS, BPF_NETKIT_PEER, SEC_NONE), | |
9af8efc4 AN |
8923 | SEC_DEF("tracepoint+", TRACEPOINT, 0, SEC_NONE, attach_tp), |
8924 | SEC_DEF("tp+", TRACEPOINT, 0, SEC_NONE, attach_tp), | |
8925 | SEC_DEF("raw_tracepoint+", RAW_TRACEPOINT, 0, SEC_NONE, attach_raw_tp), | |
8926 | SEC_DEF("raw_tp+", RAW_TRACEPOINT, 0, SEC_NONE, attach_raw_tp), | |
8927 | SEC_DEF("raw_tracepoint.w+", RAW_TRACEPOINT_WRITABLE, 0, SEC_NONE, attach_raw_tp), | |
8928 | SEC_DEF("raw_tp.w+", RAW_TRACEPOINT_WRITABLE, 0, SEC_NONE, attach_raw_tp), | |
cc7d8f2c AN |
8929 | SEC_DEF("tp_btf+", TRACING, BPF_TRACE_RAW_TP, SEC_ATTACH_BTF, attach_trace), |
8930 | SEC_DEF("fentry+", TRACING, BPF_TRACE_FENTRY, SEC_ATTACH_BTF, attach_trace), | |
8931 | SEC_DEF("fmod_ret+", TRACING, BPF_MODIFY_RETURN, SEC_ATTACH_BTF, attach_trace), | |
8932 | SEC_DEF("fexit+", TRACING, BPF_TRACE_FEXIT, SEC_ATTACH_BTF, attach_trace), | |
8933 | SEC_DEF("fentry.s+", TRACING, BPF_TRACE_FENTRY, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace), | |
8934 | SEC_DEF("fmod_ret.s+", TRACING, BPF_MODIFY_RETURN, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace), | |
8935 | SEC_DEF("fexit.s+", TRACING, BPF_TRACE_FEXIT, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace), | |
8936 | SEC_DEF("freplace+", EXT, 0, SEC_ATTACH_BTF, attach_trace), | |
8937 | SEC_DEF("lsm+", LSM, BPF_LSM_MAC, SEC_ATTACH_BTF, attach_lsm), | |
8938 | SEC_DEF("lsm.s+", LSM, BPF_LSM_MAC, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_lsm), | |
bffcf348 | 8939 | SEC_DEF("lsm_cgroup+", LSM, BPF_LSM_CGROUP, SEC_ATTACH_BTF), |
cc7d8f2c AN |
8940 | SEC_DEF("iter+", TRACING, BPF_TRACE_ITER, SEC_ATTACH_BTF, attach_iter), |
8941 | SEC_DEF("iter.s+", TRACING, BPF_TRACE_ITER, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_iter), | |
15ea31fa | 8942 | SEC_DEF("syscall", SYSCALL, 0, SEC_SLEEPABLE), |
082c4bfb | 8943 | SEC_DEF("xdp.frags/devmap", XDP, BPF_XDP_DEVMAP, SEC_XDP_FRAGS), |
4a4d4cee | 8944 | SEC_DEF("xdp/devmap", XDP, BPF_XDP_DEVMAP, SEC_ATTACHABLE), |
082c4bfb | 8945 | SEC_DEF("xdp.frags/cpumap", XDP, BPF_XDP_CPUMAP, SEC_XDP_FRAGS), |
4a4d4cee | 8946 | SEC_DEF("xdp/cpumap", XDP, BPF_XDP_CPUMAP, SEC_ATTACHABLE), |
082c4bfb | 8947 | SEC_DEF("xdp.frags", XDP, BPF_XDP, SEC_XDP_FRAGS), |
450b167f AN |
8948 | SEC_DEF("xdp", XDP, BPF_XDP, SEC_ATTACHABLE_OPT), |
8949 | SEC_DEF("perf_event", PERF_EVENT, 0, SEC_NONE), | |
8950 | SEC_DEF("lwt_in", LWT_IN, 0, SEC_NONE), | |
8951 | SEC_DEF("lwt_out", LWT_OUT, 0, SEC_NONE), | |
8952 | SEC_DEF("lwt_xmit", LWT_XMIT, 0, SEC_NONE), | |
8953 | SEC_DEF("lwt_seg6local", LWT_SEG6LOCAL, 0, SEC_NONE), | |
8954 | SEC_DEF("sockops", SOCK_OPS, BPF_CGROUP_SOCK_OPS, SEC_ATTACHABLE_OPT), | |
8955 | SEC_DEF("sk_skb/stream_parser", SK_SKB, BPF_SK_SKB_STREAM_PARSER, SEC_ATTACHABLE_OPT), | |
8956 | SEC_DEF("sk_skb/stream_verdict",SK_SKB, BPF_SK_SKB_STREAM_VERDICT, SEC_ATTACHABLE_OPT), | |
8957 | SEC_DEF("sk_skb", SK_SKB, 0, SEC_NONE), | |
8958 | SEC_DEF("sk_msg", SK_MSG, BPF_SK_MSG_VERDICT, SEC_ATTACHABLE_OPT), | |
8959 | SEC_DEF("lirc_mode2", LIRC_MODE2, BPF_LIRC_MODE2, SEC_ATTACHABLE_OPT), | |
8960 | SEC_DEF("flow_dissector", FLOW_DISSECTOR, BPF_FLOW_DISSECTOR, SEC_ATTACHABLE_OPT), | |
8961 | SEC_DEF("cgroup_skb/ingress", CGROUP_SKB, BPF_CGROUP_INET_INGRESS, SEC_ATTACHABLE_OPT), | |
8962 | SEC_DEF("cgroup_skb/egress", CGROUP_SKB, BPF_CGROUP_INET_EGRESS, SEC_ATTACHABLE_OPT), | |
8963 | SEC_DEF("cgroup/skb", CGROUP_SKB, 0, SEC_NONE), | |
8964 | SEC_DEF("cgroup/sock_create", CGROUP_SOCK, BPF_CGROUP_INET_SOCK_CREATE, SEC_ATTACHABLE), | |
8965 | SEC_DEF("cgroup/sock_release", CGROUP_SOCK, BPF_CGROUP_INET_SOCK_RELEASE, SEC_ATTACHABLE), | |
8966 | SEC_DEF("cgroup/sock", CGROUP_SOCK, BPF_CGROUP_INET_SOCK_CREATE, SEC_ATTACHABLE_OPT), | |
8967 | SEC_DEF("cgroup/post_bind4", CGROUP_SOCK, BPF_CGROUP_INET4_POST_BIND, SEC_ATTACHABLE), | |
8968 | SEC_DEF("cgroup/post_bind6", CGROUP_SOCK, BPF_CGROUP_INET6_POST_BIND, SEC_ATTACHABLE), | |
8969 | SEC_DEF("cgroup/bind4", CGROUP_SOCK_ADDR, BPF_CGROUP_INET4_BIND, SEC_ATTACHABLE), | |
8970 | SEC_DEF("cgroup/bind6", CGROUP_SOCK_ADDR, BPF_CGROUP_INET6_BIND, SEC_ATTACHABLE), | |
8971 | SEC_DEF("cgroup/connect4", CGROUP_SOCK_ADDR, BPF_CGROUP_INET4_CONNECT, SEC_ATTACHABLE), | |
8972 | SEC_DEF("cgroup/connect6", CGROUP_SOCK_ADDR, BPF_CGROUP_INET6_CONNECT, SEC_ATTACHABLE), | |
bf90438c | 8973 | SEC_DEF("cgroup/connect_unix", CGROUP_SOCK_ADDR, BPF_CGROUP_UNIX_CONNECT, SEC_ATTACHABLE), |
450b167f AN |
8974 | SEC_DEF("cgroup/sendmsg4", CGROUP_SOCK_ADDR, BPF_CGROUP_UDP4_SENDMSG, SEC_ATTACHABLE), |
8975 | SEC_DEF("cgroup/sendmsg6", CGROUP_SOCK_ADDR, BPF_CGROUP_UDP6_SENDMSG, SEC_ATTACHABLE), | |
bf90438c | 8976 | SEC_DEF("cgroup/sendmsg_unix", CGROUP_SOCK_ADDR, BPF_CGROUP_UNIX_SENDMSG, SEC_ATTACHABLE), |
450b167f AN |
8977 | SEC_DEF("cgroup/recvmsg4", CGROUP_SOCK_ADDR, BPF_CGROUP_UDP4_RECVMSG, SEC_ATTACHABLE), |
8978 | SEC_DEF("cgroup/recvmsg6", CGROUP_SOCK_ADDR, BPF_CGROUP_UDP6_RECVMSG, SEC_ATTACHABLE), | |
bf90438c | 8979 | SEC_DEF("cgroup/recvmsg_unix", CGROUP_SOCK_ADDR, BPF_CGROUP_UNIX_RECVMSG, SEC_ATTACHABLE), |
450b167f AN |
8980 | SEC_DEF("cgroup/getpeername4", CGROUP_SOCK_ADDR, BPF_CGROUP_INET4_GETPEERNAME, SEC_ATTACHABLE), |
8981 | SEC_DEF("cgroup/getpeername6", CGROUP_SOCK_ADDR, BPF_CGROUP_INET6_GETPEERNAME, SEC_ATTACHABLE), | |
bf90438c | 8982 | SEC_DEF("cgroup/getpeername_unix", CGROUP_SOCK_ADDR, BPF_CGROUP_UNIX_GETPEERNAME, SEC_ATTACHABLE), |
450b167f AN |
8983 | SEC_DEF("cgroup/getsockname4", CGROUP_SOCK_ADDR, BPF_CGROUP_INET4_GETSOCKNAME, SEC_ATTACHABLE), |
8984 | SEC_DEF("cgroup/getsockname6", CGROUP_SOCK_ADDR, BPF_CGROUP_INET6_GETSOCKNAME, SEC_ATTACHABLE), | |
bf90438c | 8985 | SEC_DEF("cgroup/getsockname_unix", CGROUP_SOCK_ADDR, BPF_CGROUP_UNIX_GETSOCKNAME, SEC_ATTACHABLE), |
450b167f AN |
8986 | SEC_DEF("cgroup/sysctl", CGROUP_SYSCTL, BPF_CGROUP_SYSCTL, SEC_ATTACHABLE), |
8987 | SEC_DEF("cgroup/getsockopt", CGROUP_SOCKOPT, BPF_CGROUP_GETSOCKOPT, SEC_ATTACHABLE), | |
8988 | SEC_DEF("cgroup/setsockopt", CGROUP_SOCKOPT, BPF_CGROUP_SETSOCKOPT, SEC_ATTACHABLE), | |
8989 | SEC_DEF("cgroup/dev", CGROUP_DEVICE, BPF_CGROUP_DEVICE, SEC_ATTACHABLE_OPT), | |
dd94d45c | 8990 | SEC_DEF("struct_ops+", STRUCT_OPS, 0, SEC_NONE), |
913b2255 | 8991 | SEC_DEF("struct_ops.s+", STRUCT_OPS, 0, SEC_SLEEPABLE), |
450b167f | 8992 | SEC_DEF("sk_lookup", SK_LOOKUP, BPF_SK_LOOKUP, SEC_ATTACHABLE), |
132328e8 | 8993 | SEC_DEF("netfilter", NETFILTER, BPF_NETFILTER, SEC_NONE), |
583c9009 | 8994 | }; |
d7be143b | 8995 | |
697f104d AN |
8996 | int libbpf_register_prog_handler(const char *sec, |
8997 | enum bpf_prog_type prog_type, | |
8998 | enum bpf_attach_type exp_attach_type, | |
8999 | const struct libbpf_prog_handler_opts *opts) | |
d7a18ea7 | 9000 | { |
697f104d | 9001 | struct bpf_sec_def *sec_def; |
d7a18ea7 | 9002 | |
697f104d AN |
9003 | if (!OPTS_VALID(opts, libbpf_prog_handler_opts)) |
9004 | return libbpf_err(-EINVAL); | |
dd94d45c | 9005 | |
697f104d AN |
9006 | if (last_custom_sec_def_handler_id == INT_MAX) /* prevent overflow */ |
9007 | return libbpf_err(-E2BIG); | |
dd94d45c | 9008 | |
697f104d AN |
9009 | if (sec) { |
9010 | sec_def = libbpf_reallocarray(custom_sec_defs, custom_sec_def_cnt + 1, | |
9011 | sizeof(*sec_def)); | |
9012 | if (!sec_def) | |
9013 | return libbpf_err(-ENOMEM); | |
dd94d45c | 9014 | |
697f104d AN |
9015 | custom_sec_defs = sec_def; |
9016 | sec_def = &custom_sec_defs[custom_sec_def_cnt]; | |
9017 | } else { | |
9018 | if (has_custom_fallback_def) | |
9019 | return libbpf_err(-EBUSY); | |
dd94d45c | 9020 | |
697f104d AN |
9021 | sec_def = &custom_fallback_def; |
9022 | } | |
9023 | ||
9024 | sec_def->sec = sec ? strdup(sec) : NULL; | |
9025 | if (sec && !sec_def->sec) | |
9026 | return libbpf_err(-ENOMEM); | |
9027 | ||
9028 | sec_def->prog_type = prog_type; | |
9029 | sec_def->expected_attach_type = exp_attach_type; | |
9030 | sec_def->cookie = OPTS_GET(opts, cookie, 0); | |
9031 | ||
9032 | sec_def->prog_setup_fn = OPTS_GET(opts, prog_setup_fn, NULL); | |
9033 | sec_def->prog_prepare_load_fn = OPTS_GET(opts, prog_prepare_load_fn, NULL); | |
9034 | sec_def->prog_attach_fn = OPTS_GET(opts, prog_attach_fn, NULL); | |
9035 | ||
9036 | sec_def->handler_id = ++last_custom_sec_def_handler_id; | |
9037 | ||
9038 | if (sec) | |
9039 | custom_sec_def_cnt++; | |
9040 | else | |
9041 | has_custom_fallback_def = true; | |
9042 | ||
9043 | return sec_def->handler_id; | |
9044 | } | |
9045 | ||
9046 | int libbpf_unregister_prog_handler(int handler_id) | |
9047 | { | |
9048 | struct bpf_sec_def *sec_defs; | |
9049 | int i; | |
9050 | ||
9051 | if (handler_id <= 0) | |
9052 | return libbpf_err(-EINVAL); | |
9053 | ||
9054 | if (has_custom_fallback_def && custom_fallback_def.handler_id == handler_id) { | |
9055 | memset(&custom_fallback_def, 0, sizeof(custom_fallback_def)); | |
9056 | has_custom_fallback_def = false; | |
9057 | return 0; | |
9058 | } | |
9059 | ||
9060 | for (i = 0; i < custom_sec_def_cnt; i++) { | |
9061 | if (custom_sec_defs[i].handler_id == handler_id) | |
9062 | break; | |
9063 | } | |
9064 | ||
9065 | if (i == custom_sec_def_cnt) | |
9066 | return libbpf_err(-ENOENT); | |
9067 | ||
9068 | free(custom_sec_defs[i].sec); | |
9069 | for (i = i + 1; i < custom_sec_def_cnt; i++) | |
9070 | custom_sec_defs[i - 1] = custom_sec_defs[i]; | |
9071 | custom_sec_def_cnt--; | |
9072 | ||
9073 | /* try to shrink the array, but it's ok if we couldn't */ | |
9074 | sec_defs = libbpf_reallocarray(custom_sec_defs, custom_sec_def_cnt, sizeof(*sec_defs)); | |
8a0260db AN |
9075 | /* if new count is zero, reallocarray can return a valid NULL result; |
9076 | * in this case the previous pointer will be freed, so we *have to* | |
9077 | * reassign old pointer to the new value (even if it's NULL) | |
9078 | */ | |
9079 | if (sec_defs || custom_sec_def_cnt == 0) | |
697f104d AN |
9080 | custom_sec_defs = sec_defs; |
9081 | ||
9082 | return 0; | |
9083 | } | |
9084 | ||
450b167f | 9085 | static bool sec_def_matches(const struct bpf_sec_def *sec_def, const char *sec_name) |
697f104d AN |
9086 | { |
9087 | size_t len = strlen(sec_def->sec); | |
9088 | ||
9089 | /* "type/" always has to have proper SEC("type/extras") form */ | |
9090 | if (sec_def->sec[len - 1] == '/') { | |
9091 | if (str_has_pfx(sec_name, sec_def->sec)) | |
9092 | return true; | |
9093 | return false; | |
9094 | } | |
9095 | ||
9096 | /* "type+" means it can be either exact SEC("type") or | |
9097 | * well-formed SEC("type/extras") with proper '/' separator | |
9098 | */ | |
9099 | if (sec_def->sec[len - 1] == '+') { | |
9100 | len--; | |
9101 | /* not even a prefix */ | |
9102 | if (strncmp(sec_name, sec_def->sec, len) != 0) | |
9103 | return false; | |
9104 | /* exact match or has '/' separator */ | |
9105 | if (sec_name[len] == '\0' || sec_name[len] == '/') | |
9106 | return true; | |
9107 | return false; | |
9108 | } | |
9109 | ||
697f104d AN |
9110 | return strcmp(sec_name, sec_def->sec) == 0; |
9111 | } | |
9112 | ||
9113 | static const struct bpf_sec_def *find_sec_def(const char *sec_name) | |
9114 | { | |
9115 | const struct bpf_sec_def *sec_def; | |
9116 | int i, n; | |
697f104d AN |
9117 | |
9118 | n = custom_sec_def_cnt; | |
9119 | for (i = 0; i < n; i++) { | |
9120 | sec_def = &custom_sec_defs[i]; | |
450b167f | 9121 | if (sec_def_matches(sec_def, sec_name)) |
697f104d AN |
9122 | return sec_def; |
9123 | } | |
9124 | ||
9125 | n = ARRAY_SIZE(section_defs); | |
9126 | for (i = 0; i < n; i++) { | |
9127 | sec_def = §ion_defs[i]; | |
450b167f | 9128 | if (sec_def_matches(sec_def, sec_name)) |
dd94d45c | 9129 | return sec_def; |
d7a18ea7 | 9130 | } |
697f104d AN |
9131 | |
9132 | if (has_custom_fallback_def) | |
9133 | return &custom_fallback_def; | |
9134 | ||
d7a18ea7 AN |
9135 | return NULL; |
9136 | } | |
9137 | ||
697f104d AN |
9138 | #define MAX_TYPE_NAME_SIZE 32 |
9139 | ||
c76e4c22 TS |
9140 | static char *libbpf_get_type_names(bool attach_type) |
9141 | { | |
d7a18ea7 | 9142 | int i, len = ARRAY_SIZE(section_defs) * MAX_TYPE_NAME_SIZE; |
c76e4c22 TS |
9143 | char *buf; |
9144 | ||
9145 | buf = malloc(len); | |
9146 | if (!buf) | |
9147 | return NULL; | |
9148 | ||
9149 | buf[0] = '\0'; | |
9150 | /* Forge string buf with all available names */ | |
d7a18ea7 | 9151 | for (i = 0; i < ARRAY_SIZE(section_defs); i++) { |
15ea31fa AN |
9152 | const struct bpf_sec_def *sec_def = §ion_defs[i]; |
9153 | ||
9154 | if (attach_type) { | |
4fa5bcfe | 9155 | if (sec_def->prog_prepare_load_fn != libbpf_prepare_prog_load) |
15ea31fa AN |
9156 | continue; |
9157 | ||
9158 | if (!(sec_def->cookie & SEC_ATTACHABLE)) | |
9159 | continue; | |
9160 | } | |
c76e4c22 | 9161 | |
d7a18ea7 | 9162 | if (strlen(buf) + strlen(section_defs[i].sec) + 2 > len) { |
c76e4c22 TS |
9163 | free(buf); |
9164 | return NULL; | |
9165 | } | |
9166 | strcat(buf, " "); | |
d7a18ea7 | 9167 | strcat(buf, section_defs[i].sec); |
c76e4c22 TS |
9168 | } |
9169 | ||
9170 | return buf; | |
9171 | } | |
9172 | ||
b60df2a0 JK |
9173 | int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, |
9174 | enum bpf_attach_type *expected_attach_type) | |
583c9009 | 9175 | { |
d7a18ea7 | 9176 | const struct bpf_sec_def *sec_def; |
c76e4c22 | 9177 | char *type_names; |
583c9009 | 9178 | |
b60df2a0 | 9179 | if (!name) |
e9fc3ce9 | 9180 | return libbpf_err(-EINVAL); |
583c9009 | 9181 | |
d7a18ea7 AN |
9182 | sec_def = find_sec_def(name); |
9183 | if (sec_def) { | |
9184 | *prog_type = sec_def->prog_type; | |
9185 | *expected_attach_type = sec_def->expected_attach_type; | |
b60df2a0 JK |
9186 | return 0; |
9187 | } | |
d7a18ea7 | 9188 | |
4a3d6c6a | 9189 | pr_debug("failed to guess program type from ELF section '%s'\n", name); |
c76e4c22 TS |
9190 | type_names = libbpf_get_type_names(false); |
9191 | if (type_names != NULL) { | |
3f519353 | 9192 | pr_debug("supported section(type) names are:%s\n", type_names); |
c76e4c22 TS |
9193 | free(type_names); |
9194 | } | |
9195 | ||
e9fc3ce9 | 9196 | return libbpf_err(-ESRCH); |
b60df2a0 | 9197 | } |
583c9009 | 9198 | |
ccde5760 DM |
9199 | const char *libbpf_bpf_attach_type_str(enum bpf_attach_type t) |
9200 | { | |
9201 | if (t < 0 || t >= ARRAY_SIZE(attach_type_name)) | |
9202 | return NULL; | |
9203 | ||
9204 | return attach_type_name[t]; | |
9205 | } | |
9206 | ||
ba5d1b58 DM |
9207 | const char *libbpf_bpf_link_type_str(enum bpf_link_type t) |
9208 | { | |
9209 | if (t < 0 || t >= ARRAY_SIZE(link_type_name)) | |
9210 | return NULL; | |
9211 | ||
9212 | return link_type_name[t]; | |
9213 | } | |
9214 | ||
3e6dc020 DM |
9215 | const char *libbpf_bpf_map_type_str(enum bpf_map_type t) |
9216 | { | |
9217 | if (t < 0 || t >= ARRAY_SIZE(map_type_name)) | |
9218 | return NULL; | |
9219 | ||
9220 | return map_type_name[t]; | |
9221 | } | |
9222 | ||
d18616e7 DM |
9223 | const char *libbpf_bpf_prog_type_str(enum bpf_prog_type t) |
9224 | { | |
9225 | if (t < 0 || t >= ARRAY_SIZE(prog_type_name)) | |
9226 | return NULL; | |
9227 | ||
9228 | return prog_type_name[t]; | |
9229 | } | |
9230 | ||
590a0088 | 9231 | static struct bpf_map *find_struct_ops_map_by_offset(struct bpf_object *obj, |
809a69d6 | 9232 | int sec_idx, |
590a0088 MKL |
9233 | size_t offset) |
9234 | { | |
9235 | struct bpf_map *map; | |
9236 | size_t i; | |
9237 | ||
9238 | for (i = 0; i < obj->nr_maps; i++) { | |
9239 | map = &obj->maps[i]; | |
9240 | if (!bpf_map__is_struct_ops(map)) | |
9241 | continue; | |
809a69d6 KFL |
9242 | if (map->sec_idx == sec_idx && |
9243 | map->sec_offset <= offset && | |
590a0088 MKL |
9244 | offset - map->sec_offset < map->def.value_size) |
9245 | return map; | |
9246 | } | |
9247 | ||
9248 | return NULL; | |
9249 | } | |
9250 | ||
9251 | /* Collect the reloc from ELF and populate the st_ops->progs[] */ | |
646f02ff | 9252 | static int bpf_object__collect_st_ops_relos(struct bpf_object *obj, |
ad23b723 | 9253 | Elf64_Shdr *shdr, Elf_Data *data) |
590a0088 MKL |
9254 | { |
9255 | const struct btf_member *member; | |
9256 | struct bpf_struct_ops *st_ops; | |
9257 | struct bpf_program *prog; | |
9258 | unsigned int shdr_idx; | |
9259 | const struct btf *btf; | |
9260 | struct bpf_map *map; | |
7e06aad5 | 9261 | unsigned int moff, insn_idx; |
590a0088 | 9262 | const char *name; |
1d1a3bcf | 9263 | __u32 member_idx; |
ad23b723 AN |
9264 | Elf64_Sym *sym; |
9265 | Elf64_Rel *rel; | |
590a0088 MKL |
9266 | int i, nrels; |
9267 | ||
590a0088 MKL |
9268 | btf = obj->btf; |
9269 | nrels = shdr->sh_size / shdr->sh_entsize; | |
9270 | for (i = 0; i < nrels; i++) { | |
ad23b723 AN |
9271 | rel = elf_rel_by_idx(data, i); |
9272 | if (!rel) { | |
590a0088 MKL |
9273 | pr_warn("struct_ops reloc: failed to get %d reloc\n", i); |
9274 | return -LIBBPF_ERRNO__FORMAT; | |
9275 | } | |
9276 | ||
ad23b723 AN |
9277 | sym = elf_sym_by_idx(obj, ELF64_R_SYM(rel->r_info)); |
9278 | if (!sym) { | |
590a0088 | 9279 | pr_warn("struct_ops reloc: symbol %zx not found\n", |
ad23b723 | 9280 | (size_t)ELF64_R_SYM(rel->r_info)); |
590a0088 MKL |
9281 | return -LIBBPF_ERRNO__FORMAT; |
9282 | } | |
9283 | ||
ad23b723 | 9284 | name = elf_sym_str(obj, sym->st_name) ?: "<?>"; |
809a69d6 | 9285 | map = find_struct_ops_map_by_offset(obj, shdr->sh_info, rel->r_offset); |
590a0088 | 9286 | if (!map) { |
ad23b723 AN |
9287 | pr_warn("struct_ops reloc: cannot find map at rel->r_offset %zu\n", |
9288 | (size_t)rel->r_offset); | |
590a0088 MKL |
9289 | return -EINVAL; |
9290 | } | |
9291 | ||
ad23b723 AN |
9292 | moff = rel->r_offset - map->sec_offset; |
9293 | shdr_idx = sym->st_shndx; | |
590a0088 | 9294 | st_ops = map->st_ops; |
ad23b723 | 9295 | pr_debug("struct_ops reloc %s: for %lld value %lld shdr_idx %u rel->r_offset %zu map->sec_offset %zu name %d (\'%s\')\n", |
590a0088 | 9296 | map->name, |
ad23b723 AN |
9297 | (long long)(rel->r_info >> 32), |
9298 | (long long)sym->st_value, | |
9299 | shdr_idx, (size_t)rel->r_offset, | |
9300 | map->sec_offset, sym->st_name, name); | |
590a0088 MKL |
9301 | |
9302 | if (shdr_idx >= SHN_LORESERVE) { | |
ad23b723 AN |
9303 | pr_warn("struct_ops reloc %s: rel->r_offset %zu shdr_idx %u unsupported non-static function\n", |
9304 | map->name, (size_t)rel->r_offset, shdr_idx); | |
590a0088 MKL |
9305 | return -LIBBPF_ERRNO__RELOC; |
9306 | } | |
ad23b723 | 9307 | if (sym->st_value % BPF_INSN_SZ) { |
7e06aad5 | 9308 | pr_warn("struct_ops reloc %s: invalid target program offset %llu\n", |
ad23b723 | 9309 | map->name, (unsigned long long)sym->st_value); |
7e06aad5 AN |
9310 | return -LIBBPF_ERRNO__FORMAT; |
9311 | } | |
ad23b723 | 9312 | insn_idx = sym->st_value / BPF_INSN_SZ; |
590a0088 MKL |
9313 | |
9314 | member = find_member_by_offset(st_ops->type, moff * 8); | |
9315 | if (!member) { | |
9316 | pr_warn("struct_ops reloc %s: cannot find member at moff %u\n", | |
9317 | map->name, moff); | |
9318 | return -EINVAL; | |
9319 | } | |
9320 | member_idx = member - btf_members(st_ops->type); | |
9321 | name = btf__name_by_offset(btf, member->name_off); | |
9322 | ||
9323 | if (!resolve_func_ptr(btf, member->type, NULL)) { | |
9324 | pr_warn("struct_ops reloc %s: cannot relocate non func ptr %s\n", | |
9325 | map->name, name); | |
9326 | return -EINVAL; | |
9327 | } | |
9328 | ||
7e06aad5 | 9329 | prog = find_prog_by_sec_insn(obj, shdr_idx, insn_idx); |
590a0088 MKL |
9330 | if (!prog) { |
9331 | pr_warn("struct_ops reloc %s: cannot find prog at shdr_idx %u to relocate func ptr %s\n", | |
9332 | map->name, shdr_idx, name); | |
9333 | return -EINVAL; | |
9334 | } | |
9335 | ||
91b4d1d1 AN |
9336 | /* prevent the use of BPF prog with invalid type */ |
9337 | if (prog->type != BPF_PROG_TYPE_STRUCT_OPS) { | |
9338 | pr_warn("struct_ops reloc %s: prog %s is not struct_ops BPF program\n", | |
9339 | map->name, prog->name); | |
9340 | return -EINVAL; | |
9341 | } | |
590a0088 | 9342 | |
91b4d1d1 AN |
9343 | /* if we haven't yet processed this BPF program, record proper |
9344 | * attach_btf_id and member_idx | |
9345 | */ | |
9346 | if (!prog->attach_btf_id) { | |
590a0088 MKL |
9347 | prog->attach_btf_id = st_ops->type_id; |
9348 | prog->expected_attach_type = member_idx; | |
590a0088 | 9349 | } |
91b4d1d1 AN |
9350 | |
9351 | /* struct_ops BPF prog can be re-used between multiple | |
809a69d6 KFL |
9352 | * .struct_ops & .struct_ops.link as long as it's the |
9353 | * same struct_ops struct definition and the same | |
9354 | * function pointer field | |
91b4d1d1 AN |
9355 | */ |
9356 | if (prog->attach_btf_id != st_ops->type_id || | |
9357 | prog->expected_attach_type != member_idx) { | |
9358 | pr_warn("struct_ops reloc %s: cannot use prog %s in sec %s with type %u attach_btf_id %u expected_attach_type %u for func ptr %s\n", | |
9359 | map->name, prog->name, prog->sec_name, prog->type, | |
9360 | prog->attach_btf_id, prog->expected_attach_type, name); | |
9361 | return -EINVAL; | |
9362 | } | |
9363 | ||
590a0088 MKL |
9364 | st_ops->progs[member_idx] = prog; |
9365 | } | |
9366 | ||
9367 | return 0; | |
590a0088 MKL |
9368 | } |
9369 | ||
a6ed02ca | 9370 | #define BTF_TRACE_PREFIX "btf_trace_" |
1e092a03 | 9371 | #define BTF_LSM_PREFIX "bpf_lsm_" |
21aef70e | 9372 | #define BTF_ITER_PREFIX "bpf_iter_" |
a6ed02ca KS |
9373 | #define BTF_MAX_NAME_SIZE 128 |
9374 | ||
67234743 AS |
9375 | void btf_get_kernel_prefix_kind(enum bpf_attach_type attach_type, |
9376 | const char **prefix, int *kind) | |
9377 | { | |
9378 | switch (attach_type) { | |
9379 | case BPF_TRACE_RAW_TP: | |
9380 | *prefix = BTF_TRACE_PREFIX; | |
9381 | *kind = BTF_KIND_TYPEDEF; | |
9382 | break; | |
9383 | case BPF_LSM_MAC: | |
bffcf348 | 9384 | case BPF_LSM_CGROUP: |
67234743 AS |
9385 | *prefix = BTF_LSM_PREFIX; |
9386 | *kind = BTF_KIND_FUNC; | |
9387 | break; | |
9388 | case BPF_TRACE_ITER: | |
9389 | *prefix = BTF_ITER_PREFIX; | |
9390 | *kind = BTF_KIND_FUNC; | |
9391 | break; | |
9392 | default: | |
9393 | *prefix = ""; | |
9394 | *kind = BTF_KIND_FUNC; | |
9395 | } | |
9396 | } | |
9397 | ||
a6ed02ca KS |
9398 | static int find_btf_by_prefix_kind(const struct btf *btf, const char *prefix, |
9399 | const char *name, __u32 kind) | |
9400 | { | |
9401 | char btf_type_name[BTF_MAX_NAME_SIZE]; | |
9402 | int ret; | |
9403 | ||
9404 | ret = snprintf(btf_type_name, sizeof(btf_type_name), | |
9405 | "%s%s", prefix, name); | |
9406 | /* snprintf returns the number of characters written excluding the | |
c139e40a | 9407 | * terminating null. So, if >= BTF_MAX_NAME_SIZE are written, it |
a6ed02ca KS |
9408 | * indicates truncation. |
9409 | */ | |
9410 | if (ret < 0 || ret >= sizeof(btf_type_name)) | |
9411 | return -ENAMETOOLONG; | |
9412 | return btf__find_by_name_kind(btf, btf_type_name, kind); | |
9413 | } | |
9414 | ||
91abb4a6 AN |
9415 | static inline int find_attach_btf_id(struct btf *btf, const char *name, |
9416 | enum bpf_attach_type attach_type) | |
a6ed02ca | 9417 | { |
67234743 AS |
9418 | const char *prefix; |
9419 | int kind; | |
a6ed02ca | 9420 | |
67234743 AS |
9421 | btf_get_kernel_prefix_kind(attach_type, &prefix, &kind); |
9422 | return find_btf_by_prefix_kind(btf, prefix, name, kind); | |
a6ed02ca KS |
9423 | } |
9424 | ||
b8c54ea4 AS |
9425 | int libbpf_find_vmlinux_btf_id(const char *name, |
9426 | enum bpf_attach_type attach_type) | |
12a8654b | 9427 | { |
a6ed02ca | 9428 | struct btf *btf; |
3521ffa2 | 9429 | int err; |
12a8654b | 9430 | |
a710eed3 | 9431 | btf = btf__load_vmlinux_btf(); |
e9fc3ce9 AN |
9432 | err = libbpf_get_error(btf); |
9433 | if (err) { | |
12a8654b | 9434 | pr_warn("vmlinux BTF is not found\n"); |
e9fc3ce9 | 9435 | return libbpf_err(err); |
12a8654b AS |
9436 | } |
9437 | ||
91abb4a6 AN |
9438 | err = find_attach_btf_id(btf, name, attach_type); |
9439 | if (err <= 0) | |
9440 | pr_warn("%s is not found in vmlinux BTF\n", name); | |
9441 | ||
3521ffa2 | 9442 | btf__free(btf); |
e9fc3ce9 | 9443 | return libbpf_err(err); |
b8c54ea4 AS |
9444 | } |
9445 | ||
e7bf94db AS |
9446 | static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd) |
9447 | { | |
813847a3 | 9448 | struct bpf_prog_info info; |
ebc7b50a | 9449 | __u32 info_len = sizeof(info); |
6cc93e2f | 9450 | struct btf *btf; |
6d2d73cd | 9451 | int err; |
e7bf94db | 9452 | |
813847a3 | 9453 | memset(&info, 0, info_len); |
629dfc66 | 9454 | err = bpf_prog_get_info_by_fd(attach_prog_fd, &info, &info_len); |
e9fc3ce9 | 9455 | if (err) { |
629dfc66 | 9456 | pr_warn("failed bpf_prog_get_info_by_fd for FD %d: %d\n", |
ebc7b50a | 9457 | attach_prog_fd, err); |
e9fc3ce9 | 9458 | return err; |
e7bf94db | 9459 | } |
6d2d73cd QM |
9460 | |
9461 | err = -EINVAL; | |
ebc7b50a | 9462 | if (!info.btf_id) { |
e7bf94db AS |
9463 | pr_warn("The target program doesn't have BTF\n"); |
9464 | goto out; | |
9465 | } | |
ebc7b50a DM |
9466 | btf = btf__load_from_kernel_by_id(info.btf_id); |
9467 | err = libbpf_get_error(btf); | |
9468 | if (err) { | |
9469 | pr_warn("Failed to get BTF %d of the program: %d\n", info.btf_id, err); | |
e7bf94db AS |
9470 | goto out; |
9471 | } | |
9472 | err = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC); | |
9473 | btf__free(btf); | |
9474 | if (err <= 0) { | |
9475 | pr_warn("%s is not found in prog's BTF\n", name); | |
9476 | goto out; | |
9477 | } | |
9478 | out: | |
e7bf94db AS |
9479 | return err; |
9480 | } | |
9481 | ||
91abb4a6 AN |
9482 | static int find_kernel_btf_id(struct bpf_object *obj, const char *attach_name, |
9483 | enum bpf_attach_type attach_type, | |
9484 | int *btf_obj_fd, int *btf_type_id) | |
9485 | { | |
9486 | int ret, i; | |
9487 | ||
9488 | ret = find_attach_btf_id(obj->btf_vmlinux, attach_name, attach_type); | |
9489 | if (ret > 0) { | |
9490 | *btf_obj_fd = 0; /* vmlinux BTF */ | |
9491 | *btf_type_id = ret; | |
9492 | return 0; | |
9493 | } | |
9494 | if (ret != -ENOENT) | |
9495 | return ret; | |
9496 | ||
9497 | ret = load_module_btfs(obj); | |
9498 | if (ret) | |
9499 | return ret; | |
9500 | ||
9501 | for (i = 0; i < obj->btf_module_cnt; i++) { | |
9502 | const struct module_btf *mod = &obj->btf_modules[i]; | |
9503 | ||
9504 | ret = find_attach_btf_id(mod->btf, attach_name, attach_type); | |
9505 | if (ret > 0) { | |
9506 | *btf_obj_fd = mod->fd; | |
9507 | *btf_type_id = ret; | |
9508 | return 0; | |
9509 | } | |
9510 | if (ret == -ENOENT) | |
9511 | continue; | |
9512 | ||
9513 | return ret; | |
9514 | } | |
9515 | ||
9516 | return -ESRCH; | |
9517 | } | |
9518 | ||
15ea31fa AN |
9519 | static int libbpf_find_attach_btf_id(struct bpf_program *prog, const char *attach_name, |
9520 | int *btf_obj_fd, int *btf_type_id) | |
b8c54ea4 | 9521 | { |
a6ed02ca KS |
9522 | enum bpf_attach_type attach_type = prog->expected_attach_type; |
9523 | __u32 attach_prog_fd = prog->attach_prog_fd; | |
b6291a6f | 9524 | int err = 0; |
b8c54ea4 | 9525 | |
91abb4a6 | 9526 | /* BPF program's BTF ID */ |
749c202c AN |
9527 | if (prog->type == BPF_PROG_TYPE_EXT || attach_prog_fd) { |
9528 | if (!attach_prog_fd) { | |
9529 | pr_warn("prog '%s': attach program FD is not set\n", prog->name); | |
9530 | return -EINVAL; | |
9531 | } | |
91abb4a6 AN |
9532 | err = libbpf_find_prog_btf_id(attach_name, attach_prog_fd); |
9533 | if (err < 0) { | |
749c202c AN |
9534 | pr_warn("prog '%s': failed to find BPF program (FD %d) BTF ID for '%s': %d\n", |
9535 | prog->name, attach_prog_fd, attach_name, err); | |
91abb4a6 AN |
9536 | return err; |
9537 | } | |
9538 | *btf_obj_fd = 0; | |
9539 | *btf_type_id = err; | |
9540 | return 0; | |
9541 | } | |
9542 | ||
9543 | /* kernel/module BTF ID */ | |
67234743 AS |
9544 | if (prog->obj->gen_loader) { |
9545 | bpf_gen__record_attach_target(prog->obj->gen_loader, attach_name, attach_type); | |
9546 | *btf_obj_fd = 0; | |
9547 | *btf_type_id = 1; | |
9548 | } else { | |
9549 | err = find_kernel_btf_id(prog->obj, attach_name, attach_type, btf_obj_fd, btf_type_id); | |
9550 | } | |
91abb4a6 | 9551 | if (err) { |
749c202c AN |
9552 | pr_warn("prog '%s': failed to find kernel BTF type ID of '%s': %d\n", |
9553 | prog->name, attach_name, err); | |
b8c54ea4 | 9554 | return err; |
12a8654b | 9555 | } |
91abb4a6 | 9556 | return 0; |
12a8654b AS |
9557 | } |
9558 | ||
956b620f AI |
9559 | int libbpf_attach_type_by_name(const char *name, |
9560 | enum bpf_attach_type *attach_type) | |
9561 | { | |
c76e4c22 | 9562 | char *type_names; |
b6291a6f | 9563 | const struct bpf_sec_def *sec_def; |
956b620f AI |
9564 | |
9565 | if (!name) | |
e9fc3ce9 | 9566 | return libbpf_err(-EINVAL); |
956b620f | 9567 | |
b6291a6f AN |
9568 | sec_def = find_sec_def(name); |
9569 | if (!sec_def) { | |
9570 | pr_debug("failed to guess attach type based on ELF section name '%s'\n", name); | |
9571 | type_names = libbpf_get_type_names(true); | |
9572 | if (type_names != NULL) { | |
9573 | pr_debug("attachable section(type) names are:%s\n", type_names); | |
9574 | free(type_names); | |
9575 | } | |
9576 | ||
9577 | return libbpf_err(-EINVAL); | |
c76e4c22 TS |
9578 | } |
9579 | ||
4fa5bcfe | 9580 | if (sec_def->prog_prepare_load_fn != libbpf_prepare_prog_load) |
15ea31fa AN |
9581 | return libbpf_err(-EINVAL); |
9582 | if (!(sec_def->cookie & SEC_ATTACHABLE)) | |
b6291a6f AN |
9583 | return libbpf_err(-EINVAL); |
9584 | ||
9585 | *attach_type = sec_def->expected_attach_type; | |
9586 | return 0; | |
956b620f AI |
9587 | } |
9588 | ||
a324aae3 | 9589 | int bpf_map__fd(const struct bpf_map *map) |
9d759a9b | 9590 | { |
e9fc3ce9 | 9591 | return map ? map->fd : libbpf_err(-EINVAL); |
9d759a9b WN |
9592 | } |
9593 | ||
aed65917 AN |
9594 | static bool map_uses_real_name(const struct bpf_map *map) |
9595 | { | |
9596 | /* Since libbpf started to support custom .data.* and .rodata.* maps, | |
9597 | * their user-visible name differs from kernel-visible name. Users see | |
9598 | * such map's corresponding ELF section name as a map name. | |
9599 | * This check distinguishes .data/.rodata from .data.* and .rodata.* | |
9600 | * maps to know which name has to be returned to the user. | |
9601 | */ | |
9602 | if (map->libbpf_type == LIBBPF_MAP_DATA && strcmp(map->real_name, DATA_SEC) != 0) | |
9603 | return true; | |
9604 | if (map->libbpf_type == LIBBPF_MAP_RODATA && strcmp(map->real_name, RODATA_SEC) != 0) | |
9605 | return true; | |
9606 | return false; | |
9607 | } | |
9608 | ||
a324aae3 | 9609 | const char *bpf_map__name(const struct bpf_map *map) |
561bbcca | 9610 | { |
aed65917 AN |
9611 | if (!map) |
9612 | return NULL; | |
9613 | ||
9614 | if (map_uses_real_name(map)) | |
9615 | return map->real_name; | |
9616 | ||
9617 | return map->name; | |
561bbcca WN |
9618 | } |
9619 | ||
1bdb6c9a AN |
9620 | enum bpf_map_type bpf_map__type(const struct bpf_map *map) |
9621 | { | |
9622 | return map->def.type; | |
9623 | } | |
9624 | ||
9625 | int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type) | |
9626 | { | |
9627 | if (map->fd >= 0) | |
e9fc3ce9 | 9628 | return libbpf_err(-EBUSY); |
1bdb6c9a AN |
9629 | map->def.type = type; |
9630 | return 0; | |
9631 | } | |
9632 | ||
9633 | __u32 bpf_map__map_flags(const struct bpf_map *map) | |
9634 | { | |
9635 | return map->def.map_flags; | |
9636 | } | |
9637 | ||
9638 | int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags) | |
9639 | { | |
9640 | if (map->fd >= 0) | |
e9fc3ce9 | 9641 | return libbpf_err(-EBUSY); |
1bdb6c9a AN |
9642 | map->def.map_flags = flags; |
9643 | return 0; | |
9644 | } | |
9645 | ||
47512102 JK |
9646 | __u64 bpf_map__map_extra(const struct bpf_map *map) |
9647 | { | |
9648 | return map->map_extra; | |
9649 | } | |
9650 | ||
9651 | int bpf_map__set_map_extra(struct bpf_map *map, __u64 map_extra) | |
9652 | { | |
9653 | if (map->fd >= 0) | |
9654 | return libbpf_err(-EBUSY); | |
9655 | map->map_extra = map_extra; | |
9656 | return 0; | |
9657 | } | |
9658 | ||
1bdb6c9a AN |
9659 | __u32 bpf_map__numa_node(const struct bpf_map *map) |
9660 | { | |
9661 | return map->numa_node; | |
9662 | } | |
9663 | ||
9664 | int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node) | |
9665 | { | |
9666 | if (map->fd >= 0) | |
e9fc3ce9 | 9667 | return libbpf_err(-EBUSY); |
1bdb6c9a AN |
9668 | map->numa_node = numa_node; |
9669 | return 0; | |
9670 | } | |
9671 | ||
9672 | __u32 bpf_map__key_size(const struct bpf_map *map) | |
9673 | { | |
9674 | return map->def.key_size; | |
9675 | } | |
9676 | ||
9677 | int bpf_map__set_key_size(struct bpf_map *map, __u32 size) | |
9678 | { | |
9679 | if (map->fd >= 0) | |
e9fc3ce9 | 9680 | return libbpf_err(-EBUSY); |
1bdb6c9a AN |
9681 | map->def.key_size = size; |
9682 | return 0; | |
9683 | } | |
9684 | ||
9685 | __u32 bpf_map__value_size(const struct bpf_map *map) | |
9686 | { | |
9687 | return map->def.value_size; | |
9688 | } | |
9689 | ||
9d0a2331 JK |
9690 | static int map_btf_datasec_resize(struct bpf_map *map, __u32 size) |
9691 | { | |
9692 | struct btf *btf; | |
9693 | struct btf_type *datasec_type, *var_type; | |
9694 | struct btf_var_secinfo *var; | |
9695 | const struct btf_type *array_type; | |
9696 | const struct btf_array *array; | |
4c857a71 JK |
9697 | int vlen, element_sz, new_array_id; |
9698 | __u32 nr_elements; | |
9d0a2331 JK |
9699 | |
9700 | /* check btf existence */ | |
9701 | btf = bpf_object__btf(map->obj); | |
9702 | if (!btf) | |
9703 | return -ENOENT; | |
9704 | ||
9705 | /* verify map is datasec */ | |
9706 | datasec_type = btf_type_by_id(btf, bpf_map__btf_value_type_id(map)); | |
9707 | if (!btf_is_datasec(datasec_type)) { | |
9708 | pr_warn("map '%s': cannot be resized, map value type is not a datasec\n", | |
9709 | bpf_map__name(map)); | |
9710 | return -EINVAL; | |
9711 | } | |
9712 | ||
9713 | /* verify datasec has at least one var */ | |
9714 | vlen = btf_vlen(datasec_type); | |
9715 | if (vlen == 0) { | |
9716 | pr_warn("map '%s': cannot be resized, map value datasec is empty\n", | |
9717 | bpf_map__name(map)); | |
9718 | return -EINVAL; | |
9719 | } | |
9720 | ||
9721 | /* verify last var in the datasec is an array */ | |
9722 | var = &btf_var_secinfos(datasec_type)[vlen - 1]; | |
9723 | var_type = btf_type_by_id(btf, var->type); | |
9724 | array_type = skip_mods_and_typedefs(btf, var_type->type, NULL); | |
9725 | if (!btf_is_array(array_type)) { | |
9726 | pr_warn("map '%s': cannot be resized, last var must be an array\n", | |
9727 | bpf_map__name(map)); | |
9728 | return -EINVAL; | |
9729 | } | |
9730 | ||
9731 | /* verify request size aligns with array */ | |
9732 | array = btf_array(array_type); | |
9733 | element_sz = btf__resolve_size(btf, array->type); | |
9734 | if (element_sz <= 0 || (size - var->offset) % element_sz != 0) { | |
9735 | pr_warn("map '%s': cannot be resized, element size (%d) doesn't align with new total size (%u)\n", | |
9736 | bpf_map__name(map), element_sz, size); | |
9737 | return -EINVAL; | |
9738 | } | |
9739 | ||
9740 | /* create a new array based on the existing array, but with new length */ | |
9741 | nr_elements = (size - var->offset) / element_sz; | |
9742 | new_array_id = btf__add_array(btf, array->index_type, array->type, nr_elements); | |
9743 | if (new_array_id < 0) | |
9744 | return new_array_id; | |
9745 | ||
9746 | /* adding a new btf type invalidates existing pointers to btf objects, | |
9747 | * so refresh pointers before proceeding | |
9748 | */ | |
9749 | datasec_type = btf_type_by_id(btf, map->btf_value_type_id); | |
9750 | var = &btf_var_secinfos(datasec_type)[vlen - 1]; | |
9751 | var_type = btf_type_by_id(btf, var->type); | |
9752 | ||
9753 | /* finally update btf info */ | |
9754 | datasec_type->size = size; | |
9755 | var->size = size - var->offset; | |
9756 | var_type->type = new_array_id; | |
9757 | ||
9758 | return 0; | |
9759 | } | |
9760 | ||
1bdb6c9a AN |
9761 | int bpf_map__set_value_size(struct bpf_map *map, __u32 size) |
9762 | { | |
9763 | if (map->fd >= 0) | |
e9fc3ce9 | 9764 | return libbpf_err(-EBUSY); |
9d0a2331 JK |
9765 | |
9766 | if (map->mmaped) { | |
9767 | int err; | |
9768 | size_t mmap_old_sz, mmap_new_sz; | |
9769 | ||
9770 | mmap_old_sz = bpf_map_mmap_sz(map->def.value_size, map->def.max_entries); | |
9771 | mmap_new_sz = bpf_map_mmap_sz(size, map->def.max_entries); | |
9772 | err = bpf_map_mmap_resize(map, mmap_old_sz, mmap_new_sz); | |
9773 | if (err) { | |
9774 | pr_warn("map '%s': failed to resize memory-mapped region: %d\n", | |
9775 | bpf_map__name(map), err); | |
9776 | return err; | |
9777 | } | |
9778 | err = map_btf_datasec_resize(map, size); | |
9779 | if (err && err != -ENOENT) { | |
9780 | pr_warn("map '%s': failed to adjust resized BTF, clearing BTF key/value info: %d\n", | |
9781 | bpf_map__name(map), err); | |
9782 | map->btf_value_type_id = 0; | |
9783 | map->btf_key_type_id = 0; | |
9784 | } | |
9785 | } | |
9786 | ||
1bdb6c9a AN |
9787 | map->def.value_size = size; |
9788 | return 0; | |
9789 | } | |
9790 | ||
5b891af7 | 9791 | __u32 bpf_map__btf_key_type_id(const struct bpf_map *map) |
8a138aed | 9792 | { |
61746dbe | 9793 | return map ? map->btf_key_type_id : 0; |
8a138aed MKL |
9794 | } |
9795 | ||
5b891af7 | 9796 | __u32 bpf_map__btf_value_type_id(const struct bpf_map *map) |
8a138aed | 9797 | { |
61746dbe | 9798 | return map ? map->btf_value_type_id : 0; |
8a138aed MKL |
9799 | } |
9800 | ||
e2842be5 THJ |
9801 | int bpf_map__set_initial_value(struct bpf_map *map, |
9802 | const void *data, size_t size) | |
9803 | { | |
9804 | if (!map->mmaped || map->libbpf_type == LIBBPF_MAP_KCONFIG || | |
9805 | size != map->def.value_size || map->fd >= 0) | |
e9fc3ce9 | 9806 | return libbpf_err(-EINVAL); |
e2842be5 THJ |
9807 | |
9808 | memcpy(map->mmaped, data, size); | |
9809 | return 0; | |
9810 | } | |
9811 | ||
9d0a2331 | 9812 | void *bpf_map__initial_value(struct bpf_map *map, size_t *psize) |
7723256b AS |
9813 | { |
9814 | if (!map->mmaped) | |
9815 | return NULL; | |
9816 | *psize = map->def.value_size; | |
9817 | return map->mmaped; | |
9818 | } | |
9819 | ||
a324aae3 | 9820 | bool bpf_map__is_internal(const struct bpf_map *map) |
d859900c DB |
9821 | { |
9822 | return map->libbpf_type != LIBBPF_MAP_UNSPEC; | |
9823 | } | |
9824 | ||
1bdb6c9a AN |
9825 | __u32 bpf_map__ifindex(const struct bpf_map *map) |
9826 | { | |
9827 | return map->map_ifindex; | |
9828 | } | |
9829 | ||
9830 | int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex) | |
9aba3613 | 9831 | { |
1bdb6c9a | 9832 | if (map->fd >= 0) |
e9fc3ce9 | 9833 | return libbpf_err(-EBUSY); |
9aba3613 | 9834 | map->map_ifindex = ifindex; |
1bdb6c9a | 9835 | return 0; |
9aba3613 JK |
9836 | } |
9837 | ||
addb9fc9 NS |
9838 | int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd) |
9839 | { | |
9840 | if (!bpf_map_type__is_map_in_map(map->def.type)) { | |
be18010e | 9841 | pr_warn("error: unsupported map type\n"); |
e9fc3ce9 | 9842 | return libbpf_err(-EINVAL); |
addb9fc9 NS |
9843 | } |
9844 | if (map->inner_map_fd != -1) { | |
be18010e | 9845 | pr_warn("error: inner_map_fd already specified\n"); |
e9fc3ce9 | 9846 | return libbpf_err(-EINVAL); |
addb9fc9 | 9847 | } |
8f7b239e AN |
9848 | if (map->inner_map) { |
9849 | bpf_map__destroy(map->inner_map); | |
9850 | zfree(&map->inner_map); | |
9851 | } | |
addb9fc9 NS |
9852 | map->inner_map_fd = fd; |
9853 | return 0; | |
9854 | } | |
9855 | ||
0c19a9fb | 9856 | static struct bpf_map * |
a324aae3 | 9857 | __bpf_map__iter(const struct bpf_map *m, const struct bpf_object *obj, int i) |
9d759a9b | 9858 | { |
0c19a9fb | 9859 | ssize_t idx; |
9d759a9b WN |
9860 | struct bpf_map *s, *e; |
9861 | ||
9862 | if (!obj || !obj->maps) | |
e9fc3ce9 | 9863 | return errno = EINVAL, NULL; |
9d759a9b WN |
9864 | |
9865 | s = obj->maps; | |
9866 | e = obj->maps + obj->nr_maps; | |
9867 | ||
0c19a9fb | 9868 | if ((m < s) || (m >= e)) { |
be18010e KW |
9869 | pr_warn("error in %s: map handler doesn't belong to object\n", |
9870 | __func__); | |
e9fc3ce9 | 9871 | return errno = EINVAL, NULL; |
9d759a9b WN |
9872 | } |
9873 | ||
0c19a9fb SF |
9874 | idx = (m - obj->maps) + i; |
9875 | if (idx >= obj->nr_maps || idx < 0) | |
9d759a9b WN |
9876 | return NULL; |
9877 | return &obj->maps[idx]; | |
9878 | } | |
561bbcca | 9879 | |
2088a3a7 HC |
9880 | struct bpf_map * |
9881 | bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *prev) | |
0c19a9fb SF |
9882 | { |
9883 | if (prev == NULL) | |
9884 | return obj->maps; | |
9885 | ||
9886 | return __bpf_map__iter(prev, obj, 1); | |
9887 | } | |
9888 | ||
2088a3a7 HC |
9889 | struct bpf_map * |
9890 | bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *next) | |
0c19a9fb SF |
9891 | { |
9892 | if (next == NULL) { | |
9893 | if (!obj->nr_maps) | |
9894 | return NULL; | |
9895 | return obj->maps + obj->nr_maps - 1; | |
9896 | } | |
9897 | ||
9898 | return __bpf_map__iter(next, obj, -1); | |
9899 | } | |
9900 | ||
561bbcca | 9901 | struct bpf_map * |
a324aae3 | 9902 | bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name) |
561bbcca WN |
9903 | { |
9904 | struct bpf_map *pos; | |
9905 | ||
f74a53d9 | 9906 | bpf_object__for_each_map(pos, obj) { |
26071635 AN |
9907 | /* if it's a special internal map name (which always starts |
9908 | * with dot) then check if that special name matches the | |
9909 | * real map name (ELF section name) | |
9910 | */ | |
9911 | if (name[0] == '.') { | |
9912 | if (pos->real_name && strcmp(pos->real_name, name) == 0) | |
9913 | return pos; | |
9914 | continue; | |
9915 | } | |
9916 | /* otherwise map name has to be an exact match */ | |
aed65917 AN |
9917 | if (map_uses_real_name(pos)) { |
9918 | if (strcmp(pos->real_name, name) == 0) | |
9919 | return pos; | |
9920 | continue; | |
9921 | } | |
9922 | if (strcmp(pos->name, name) == 0) | |
561bbcca WN |
9923 | return pos; |
9924 | } | |
e9fc3ce9 | 9925 | return errno = ENOENT, NULL; |
561bbcca | 9926 | } |
5a6acad1 | 9927 | |
f3cea32d | 9928 | int |
a324aae3 | 9929 | bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name) |
f3cea32d MF |
9930 | { |
9931 | return bpf_map__fd(bpf_object__find_map_by_name(obj, name)); | |
9932 | } | |
9933 | ||
737d0646 AN |
9934 | static int validate_map_op(const struct bpf_map *map, size_t key_sz, |
9935 | size_t value_sz, bool check_value_sz) | |
9936 | { | |
9937 | if (map->fd <= 0) | |
9938 | return -ENOENT; | |
9939 | ||
9940 | if (map->def.key_size != key_sz) { | |
9941 | pr_warn("map '%s': unexpected key size %zu provided, expected %u\n", | |
9942 | map->name, key_sz, map->def.key_size); | |
9943 | return -EINVAL; | |
9944 | } | |
9945 | ||
9946 | if (!check_value_sz) | |
9947 | return 0; | |
9948 | ||
9949 | switch (map->def.type) { | |
9950 | case BPF_MAP_TYPE_PERCPU_ARRAY: | |
9951 | case BPF_MAP_TYPE_PERCPU_HASH: | |
9952 | case BPF_MAP_TYPE_LRU_PERCPU_HASH: | |
9953 | case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: { | |
9954 | int num_cpu = libbpf_num_possible_cpus(); | |
9955 | size_t elem_sz = roundup(map->def.value_size, 8); | |
9956 | ||
9957 | if (value_sz != num_cpu * elem_sz) { | |
9958 | pr_warn("map '%s': unexpected value size %zu provided for per-CPU map, expected %d * %zu = %zd\n", | |
9959 | map->name, value_sz, num_cpu, elem_sz, num_cpu * elem_sz); | |
9960 | return -EINVAL; | |
9961 | } | |
9962 | break; | |
9963 | } | |
9964 | default: | |
9965 | if (map->def.value_size != value_sz) { | |
9966 | pr_warn("map '%s': unexpected value size %zu provided, expected %u\n", | |
9967 | map->name, value_sz, map->def.value_size); | |
9968 | return -EINVAL; | |
9969 | } | |
9970 | break; | |
9971 | } | |
9972 | return 0; | |
9973 | } | |
9974 | ||
9975 | int bpf_map__lookup_elem(const struct bpf_map *map, | |
9976 | const void *key, size_t key_sz, | |
9977 | void *value, size_t value_sz, __u64 flags) | |
9978 | { | |
9979 | int err; | |
9980 | ||
9981 | err = validate_map_op(map, key_sz, value_sz, true); | |
9982 | if (err) | |
9983 | return libbpf_err(err); | |
9984 | ||
9985 | return bpf_map_lookup_elem_flags(map->fd, key, value, flags); | |
9986 | } | |
9987 | ||
9988 | int bpf_map__update_elem(const struct bpf_map *map, | |
9989 | const void *key, size_t key_sz, | |
9990 | const void *value, size_t value_sz, __u64 flags) | |
9991 | { | |
9992 | int err; | |
9993 | ||
9994 | err = validate_map_op(map, key_sz, value_sz, true); | |
9995 | if (err) | |
9996 | return libbpf_err(err); | |
9997 | ||
9998 | return bpf_map_update_elem(map->fd, key, value, flags); | |
9999 | } | |
10000 | ||
10001 | int bpf_map__delete_elem(const struct bpf_map *map, | |
10002 | const void *key, size_t key_sz, __u64 flags) | |
10003 | { | |
10004 | int err; | |
10005 | ||
10006 | err = validate_map_op(map, key_sz, 0, false /* check_value_sz */); | |
10007 | if (err) | |
10008 | return libbpf_err(err); | |
10009 | ||
10010 | return bpf_map_delete_elem_flags(map->fd, key, flags); | |
10011 | } | |
10012 | ||
10013 | int bpf_map__lookup_and_delete_elem(const struct bpf_map *map, | |
10014 | const void *key, size_t key_sz, | |
10015 | void *value, size_t value_sz, __u64 flags) | |
10016 | { | |
10017 | int err; | |
10018 | ||
10019 | err = validate_map_op(map, key_sz, value_sz, true); | |
10020 | if (err) | |
10021 | return libbpf_err(err); | |
10022 | ||
10023 | return bpf_map_lookup_and_delete_elem_flags(map->fd, key, value, flags); | |
10024 | } | |
10025 | ||
10026 | int bpf_map__get_next_key(const struct bpf_map *map, | |
10027 | const void *cur_key, void *next_key, size_t key_sz) | |
10028 | { | |
10029 | int err; | |
10030 | ||
10031 | err = validate_map_op(map, key_sz, 0, false /* check_value_sz */); | |
10032 | if (err) | |
10033 | return libbpf_err(err); | |
10034 | ||
10035 | return bpf_map_get_next_key(map->fd, cur_key, next_key); | |
10036 | } | |
10037 | ||
e28ff1a8 JS |
10038 | long libbpf_get_error(const void *ptr) |
10039 | { | |
e9fc3ce9 AN |
10040 | if (!IS_ERR_OR_NULL(ptr)) |
10041 | return 0; | |
10042 | ||
10043 | if (IS_ERR(ptr)) | |
10044 | errno = -PTR_ERR(ptr); | |
10045 | ||
10046 | /* If ptr == NULL, then errno should be already set by the failing | |
10047 | * API, because libbpf never returns NULL on success and it now always | |
10048 | * sets errno on error. So no extra errno handling for ptr == NULL | |
10049 | * case. | |
10050 | */ | |
10051 | return -errno; | |
e28ff1a8 | 10052 | } |
6f6d33f3 | 10053 | |
cc4f864b AN |
10054 | /* Replace link's underlying BPF program with the new one */ |
10055 | int bpf_link__update_program(struct bpf_link *link, struct bpf_program *prog) | |
10056 | { | |
e9fc3ce9 | 10057 | int ret; |
c139e40a | 10058 | |
e9fc3ce9 AN |
10059 | ret = bpf_link_update(bpf_link__fd(link), bpf_program__fd(prog), NULL); |
10060 | return libbpf_err_errno(ret); | |
cc4f864b AN |
10061 | } |
10062 | ||
d6958706 AN |
10063 | /* Release "ownership" of underlying BPF resource (typically, BPF program |
10064 | * attached to some BPF hook, e.g., tracepoint, kprobe, etc). Disconnected | |
10065 | * link, when destructed through bpf_link__destroy() call won't attempt to | |
10066 | * detach/unregisted that BPF resource. This is useful in situations where, | |
10067 | * say, attached BPF program has to outlive userspace program that attached it | |
10068 | * in the system. Depending on type of BPF program, though, there might be | |
10069 | * additional steps (like pinning BPF program in BPF FS) necessary to ensure | |
10070 | * exit of userspace program doesn't trigger automatic detachment and clean up | |
10071 | * inside the kernel. | |
10072 | */ | |
10073 | void bpf_link__disconnect(struct bpf_link *link) | |
10074 | { | |
10075 | link->disconnected = true; | |
10076 | } | |
10077 | ||
1c2e9efc AN |
10078 | int bpf_link__destroy(struct bpf_link *link) |
10079 | { | |
d6958706 | 10080 | int err = 0; |
1c2e9efc | 10081 | |
50450fc7 | 10082 | if (IS_ERR_OR_NULL(link)) |
1c2e9efc AN |
10083 | return 0; |
10084 | ||
d6958706 AN |
10085 | if (!link->disconnected && link->detach) |
10086 | err = link->detach(link); | |
c016b68e AN |
10087 | if (link->pin_path) |
10088 | free(link->pin_path); | |
d88b71d4 AN |
10089 | if (link->dealloc) |
10090 | link->dealloc(link); | |
10091 | else | |
10092 | free(link); | |
1c2e9efc | 10093 | |
e9fc3ce9 | 10094 | return libbpf_err(err); |
1c2e9efc AN |
10095 | } |
10096 | ||
c016b68e AN |
10097 | int bpf_link__fd(const struct bpf_link *link) |
10098 | { | |
10099 | return link->fd; | |
10100 | } | |
10101 | ||
10102 | const char *bpf_link__pin_path(const struct bpf_link *link) | |
10103 | { | |
10104 | return link->pin_path; | |
10105 | } | |
10106 | ||
10107 | static int bpf_link__detach_fd(struct bpf_link *link) | |
10108 | { | |
e9fc3ce9 | 10109 | return libbpf_err_errno(close(link->fd)); |
c016b68e AN |
10110 | } |
10111 | ||
10112 | struct bpf_link *bpf_link__open(const char *path) | |
10113 | { | |
10114 | struct bpf_link *link; | |
10115 | int fd; | |
10116 | ||
10117 | fd = bpf_obj_get(path); | |
10118 | if (fd < 0) { | |
10119 | fd = -errno; | |
10120 | pr_warn("failed to open link at %s: %d\n", path, fd); | |
e9fc3ce9 | 10121 | return libbpf_err_ptr(fd); |
c016b68e AN |
10122 | } |
10123 | ||
10124 | link = calloc(1, sizeof(*link)); | |
10125 | if (!link) { | |
10126 | close(fd); | |
e9fc3ce9 | 10127 | return libbpf_err_ptr(-ENOMEM); |
c016b68e AN |
10128 | } |
10129 | link->detach = &bpf_link__detach_fd; | |
10130 | link->fd = fd; | |
10131 | ||
10132 | link->pin_path = strdup(path); | |
10133 | if (!link->pin_path) { | |
10134 | bpf_link__destroy(link); | |
e9fc3ce9 | 10135 | return libbpf_err_ptr(-ENOMEM); |
c016b68e AN |
10136 | } |
10137 | ||
10138 | return link; | |
10139 | } | |
10140 | ||
2e49527e AN |
10141 | int bpf_link__detach(struct bpf_link *link) |
10142 | { | |
10143 | return bpf_link_detach(link->fd) ? -errno : 0; | |
10144 | } | |
10145 | ||
c016b68e AN |
10146 | int bpf_link__pin(struct bpf_link *link, const char *path) |
10147 | { | |
10148 | int err; | |
10149 | ||
10150 | if (link->pin_path) | |
e9fc3ce9 | 10151 | return libbpf_err(-EBUSY); |
c016b68e AN |
10152 | err = make_parent_dir(path); |
10153 | if (err) | |
e9fc3ce9 | 10154 | return libbpf_err(err); |
c016b68e AN |
10155 | err = check_path(path); |
10156 | if (err) | |
e9fc3ce9 | 10157 | return libbpf_err(err); |
c016b68e AN |
10158 | |
10159 | link->pin_path = strdup(path); | |
10160 | if (!link->pin_path) | |
e9fc3ce9 | 10161 | return libbpf_err(-ENOMEM); |
c016b68e AN |
10162 | |
10163 | if (bpf_obj_pin(link->fd, link->pin_path)) { | |
10164 | err = -errno; | |
10165 | zfree(&link->pin_path); | |
e9fc3ce9 | 10166 | return libbpf_err(err); |
c016b68e AN |
10167 | } |
10168 | ||
10169 | pr_debug("link fd=%d: pinned at %s\n", link->fd, link->pin_path); | |
10170 | return 0; | |
10171 | } | |
10172 | ||
10173 | int bpf_link__unpin(struct bpf_link *link) | |
10174 | { | |
10175 | int err; | |
10176 | ||
10177 | if (!link->pin_path) | |
e9fc3ce9 | 10178 | return libbpf_err(-EINVAL); |
c016b68e AN |
10179 | |
10180 | err = unlink(link->pin_path); | |
10181 | if (err != 0) | |
af0efa05 | 10182 | return -errno; |
c016b68e AN |
10183 | |
10184 | pr_debug("link fd=%d: unpinned from %s\n", link->fd, link->pin_path); | |
10185 | zfree(&link->pin_path); | |
10186 | return 0; | |
10187 | } | |
63f2f5ee | 10188 | |
668ace0e AN |
10189 | struct bpf_link_perf { |
10190 | struct bpf_link link; | |
10191 | int perf_event_fd; | |
ca304b40 RDT |
10192 | /* legacy kprobe support: keep track of probe identifier and type */ |
10193 | char *legacy_probe_name; | |
46ed5fc3 | 10194 | bool legacy_is_kprobe; |
ca304b40 | 10195 | bool legacy_is_retprobe; |
668ace0e AN |
10196 | }; |
10197 | ||
46ed5fc3 | 10198 | static int remove_kprobe_event_legacy(const char *probe_name, bool retprobe); |
cc10623c | 10199 | static int remove_uprobe_event_legacy(const char *probe_name, bool retprobe); |
46ed5fc3 | 10200 | |
668ace0e | 10201 | static int bpf_link_perf_detach(struct bpf_link *link) |
63f2f5ee | 10202 | { |
668ace0e AN |
10203 | struct bpf_link_perf *perf_link = container_of(link, struct bpf_link_perf, link); |
10204 | int err = 0; | |
63f2f5ee | 10205 | |
668ace0e | 10206 | if (ioctl(perf_link->perf_event_fd, PERF_EVENT_IOC_DISABLE, 0) < 0) |
63f2f5ee AN |
10207 | err = -errno; |
10208 | ||
668ace0e AN |
10209 | if (perf_link->perf_event_fd != link->fd) |
10210 | close(perf_link->perf_event_fd); | |
c016b68e | 10211 | close(link->fd); |
668ace0e | 10212 | |
cc10623c | 10213 | /* legacy uprobe/kprobe needs to be removed after perf event fd closure */ |
46ed5fc3 AN |
10214 | if (perf_link->legacy_probe_name) { |
10215 | if (perf_link->legacy_is_kprobe) { | |
10216 | err = remove_kprobe_event_legacy(perf_link->legacy_probe_name, | |
10217 | perf_link->legacy_is_retprobe); | |
cc10623c AN |
10218 | } else { |
10219 | err = remove_uprobe_event_legacy(perf_link->legacy_probe_name, | |
10220 | perf_link->legacy_is_retprobe); | |
46ed5fc3 AN |
10221 | } |
10222 | } | |
ca304b40 RDT |
10223 | |
10224 | return err; | |
63f2f5ee AN |
10225 | } |
10226 | ||
668ace0e AN |
10227 | static void bpf_link_perf_dealloc(struct bpf_link *link) |
10228 | { | |
10229 | struct bpf_link_perf *perf_link = container_of(link, struct bpf_link_perf, link); | |
10230 | ||
ca304b40 | 10231 | free(perf_link->legacy_probe_name); |
668ace0e AN |
10232 | free(perf_link); |
10233 | } | |
10234 | ||
942025c9 | 10235 | struct bpf_link *bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd, |
47faff37 | 10236 | const struct bpf_perf_event_opts *opts) |
63f2f5ee AN |
10237 | { |
10238 | char errmsg[STRERR_BUFSIZE]; | |
668ace0e AN |
10239 | struct bpf_link_perf *link; |
10240 | int prog_fd, link_fd = -1, err; | |
f8b299bc | 10241 | bool force_ioctl_attach; |
63f2f5ee | 10242 | |
47faff37 AN |
10243 | if (!OPTS_VALID(opts, bpf_perf_event_opts)) |
10244 | return libbpf_err_ptr(-EINVAL); | |
10245 | ||
63f2f5ee | 10246 | if (pfd < 0) { |
52109584 AN |
10247 | pr_warn("prog '%s': invalid perf event FD %d\n", |
10248 | prog->name, pfd); | |
e9fc3ce9 | 10249 | return libbpf_err_ptr(-EINVAL); |
63f2f5ee AN |
10250 | } |
10251 | prog_fd = bpf_program__fd(prog); | |
10252 | if (prog_fd < 0) { | |
52109584 AN |
10253 | pr_warn("prog '%s': can't attach BPF program w/o FD (did you load it?)\n", |
10254 | prog->name); | |
e9fc3ce9 | 10255 | return libbpf_err_ptr(-EINVAL); |
63f2f5ee AN |
10256 | } |
10257 | ||
d6958706 | 10258 | link = calloc(1, sizeof(*link)); |
63f2f5ee | 10259 | if (!link) |
e9fc3ce9 | 10260 | return libbpf_err_ptr(-ENOMEM); |
668ace0e AN |
10261 | link->link.detach = &bpf_link_perf_detach; |
10262 | link->link.dealloc = &bpf_link_perf_dealloc; | |
10263 | link->perf_event_fd = pfd; | |
63f2f5ee | 10264 | |
f8b299bc MD |
10265 | force_ioctl_attach = OPTS_GET(opts, force_ioctl_attach, false); |
10266 | if (kernel_supports(prog->obj, FEAT_PERF_LINK) && !force_ioctl_attach) { | |
47faff37 AN |
10267 | DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_opts, |
10268 | .perf_event.bpf_cookie = OPTS_GET(opts, bpf_cookie, 0)); | |
10269 | ||
10270 | link_fd = bpf_link_create(prog_fd, pfd, BPF_PERF_EVENT, &link_opts); | |
668ace0e AN |
10271 | if (link_fd < 0) { |
10272 | err = -errno; | |
10273 | pr_warn("prog '%s': failed to create BPF link for perf_event FD %d: %d (%s)\n", | |
10274 | prog->name, pfd, | |
10275 | err, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
10276 | goto err_out; | |
10277 | } | |
10278 | link->link.fd = link_fd; | |
10279 | } else { | |
47faff37 AN |
10280 | if (OPTS_GET(opts, bpf_cookie, 0)) { |
10281 | pr_warn("prog '%s': user context value is not supported\n", prog->name); | |
10282 | err = -EOPNOTSUPP; | |
10283 | goto err_out; | |
10284 | } | |
10285 | ||
668ace0e AN |
10286 | if (ioctl(pfd, PERF_EVENT_IOC_SET_BPF, prog_fd) < 0) { |
10287 | err = -errno; | |
10288 | pr_warn("prog '%s': failed to attach to perf_event FD %d: %s\n", | |
10289 | prog->name, pfd, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
10290 | if (err == -EPROTO) | |
10291 | pr_warn("prog '%s': try add PERF_SAMPLE_CALLCHAIN to or remove exclude_callchain_[kernel|user] from pfd %d\n", | |
10292 | prog->name, pfd); | |
10293 | goto err_out; | |
10294 | } | |
10295 | link->link.fd = pfd; | |
63f2f5ee AN |
10296 | } |
10297 | if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) { | |
10298 | err = -errno; | |
668ace0e | 10299 | pr_warn("prog '%s': failed to enable perf_event FD %d: %s\n", |
52109584 | 10300 | prog->name, pfd, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
668ace0e | 10301 | goto err_out; |
63f2f5ee | 10302 | } |
668ace0e AN |
10303 | |
10304 | return &link->link; | |
10305 | err_out: | |
10306 | if (link_fd >= 0) | |
10307 | close(link_fd); | |
10308 | free(link); | |
10309 | return libbpf_err_ptr(err); | |
63f2f5ee AN |
10310 | } |
10311 | ||
942025c9 | 10312 | struct bpf_link *bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd) |
47faff37 AN |
10313 | { |
10314 | return bpf_program__attach_perf_event_opts(prog, pfd, NULL); | |
10315 | } | |
10316 | ||
b2650027 AN |
10317 | /* |
10318 | * this function is expected to parse integer in the range of [0, 2^31-1] from | |
10319 | * given file using scanf format string fmt. If actual parsed value is | |
10320 | * negative, the result might be indistinguishable from error | |
10321 | */ | |
10322 | static int parse_uint_from_file(const char *file, const char *fmt) | |
10323 | { | |
10324 | char buf[STRERR_BUFSIZE]; | |
10325 | int err, ret; | |
10326 | FILE *f; | |
10327 | ||
59842c54 | 10328 | f = fopen(file, "re"); |
b2650027 AN |
10329 | if (!f) { |
10330 | err = -errno; | |
10331 | pr_debug("failed to open '%s': %s\n", file, | |
10332 | libbpf_strerror_r(err, buf, sizeof(buf))); | |
10333 | return err; | |
10334 | } | |
10335 | err = fscanf(f, fmt, &ret); | |
10336 | if (err != 1) { | |
10337 | err = err == EOF ? -EIO : -errno; | |
10338 | pr_debug("failed to parse '%s': %s\n", file, | |
10339 | libbpf_strerror_r(err, buf, sizeof(buf))); | |
10340 | fclose(f); | |
10341 | return err; | |
10342 | } | |
10343 | fclose(f); | |
10344 | return ret; | |
10345 | } | |
10346 | ||
10347 | static int determine_kprobe_perf_type(void) | |
10348 | { | |
10349 | const char *file = "/sys/bus/event_source/devices/kprobe/type"; | |
10350 | ||
10351 | return parse_uint_from_file(file, "%d\n"); | |
10352 | } | |
10353 | ||
10354 | static int determine_uprobe_perf_type(void) | |
10355 | { | |
10356 | const char *file = "/sys/bus/event_source/devices/uprobe/type"; | |
10357 | ||
10358 | return parse_uint_from_file(file, "%d\n"); | |
10359 | } | |
10360 | ||
10361 | static int determine_kprobe_retprobe_bit(void) | |
10362 | { | |
10363 | const char *file = "/sys/bus/event_source/devices/kprobe/format/retprobe"; | |
10364 | ||
10365 | return parse_uint_from_file(file, "config:%d\n"); | |
10366 | } | |
10367 | ||
10368 | static int determine_uprobe_retprobe_bit(void) | |
10369 | { | |
10370 | const char *file = "/sys/bus/event_source/devices/uprobe/format/retprobe"; | |
10371 | ||
10372 | return parse_uint_from_file(file, "config:%d\n"); | |
10373 | } | |
10374 | ||
5e3b8356 AN |
10375 | #define PERF_UPROBE_REF_CTR_OFFSET_BITS 32 |
10376 | #define PERF_UPROBE_REF_CTR_OFFSET_SHIFT 32 | |
10377 | ||
b2650027 | 10378 | static int perf_event_open_probe(bool uprobe, bool retprobe, const char *name, |
5e3b8356 | 10379 | uint64_t offset, int pid, size_t ref_ctr_off) |
b2650027 | 10380 | { |
813847a3 AN |
10381 | const size_t attr_sz = sizeof(struct perf_event_attr); |
10382 | struct perf_event_attr attr; | |
b2650027 | 10383 | char errmsg[STRERR_BUFSIZE]; |
708ac5be | 10384 | int type, pfd; |
b2650027 | 10385 | |
1520e846 | 10386 | if ((__u64)ref_ctr_off >= (1ULL << PERF_UPROBE_REF_CTR_OFFSET_BITS)) |
5e3b8356 AN |
10387 | return -EINVAL; |
10388 | ||
813847a3 AN |
10389 | memset(&attr, 0, attr_sz); |
10390 | ||
b2650027 AN |
10391 | type = uprobe ? determine_uprobe_perf_type() |
10392 | : determine_kprobe_perf_type(); | |
10393 | if (type < 0) { | |
be18010e KW |
10394 | pr_warn("failed to determine %s perf type: %s\n", |
10395 | uprobe ? "uprobe" : "kprobe", | |
10396 | libbpf_strerror_r(type, errmsg, sizeof(errmsg))); | |
b2650027 AN |
10397 | return type; |
10398 | } | |
10399 | if (retprobe) { | |
10400 | int bit = uprobe ? determine_uprobe_retprobe_bit() | |
10401 | : determine_kprobe_retprobe_bit(); | |
10402 | ||
10403 | if (bit < 0) { | |
be18010e KW |
10404 | pr_warn("failed to determine %s retprobe bit: %s\n", |
10405 | uprobe ? "uprobe" : "kprobe", | |
10406 | libbpf_strerror_r(bit, errmsg, sizeof(errmsg))); | |
b2650027 AN |
10407 | return bit; |
10408 | } | |
10409 | attr.config |= 1 << bit; | |
10410 | } | |
813847a3 | 10411 | attr.size = attr_sz; |
b2650027 | 10412 | attr.type = type; |
5e3b8356 | 10413 | attr.config |= (__u64)ref_ctr_off << PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
36db2a94 AN |
10414 | attr.config1 = ptr_to_u64(name); /* kprobe_func or uprobe_path */ |
10415 | attr.config2 = offset; /* kprobe_addr or probe_offset */ | |
b2650027 AN |
10416 | |
10417 | /* pid filter is meaningful only for uprobes */ | |
10418 | pfd = syscall(__NR_perf_event_open, &attr, | |
10419 | pid < 0 ? -1 : pid /* pid */, | |
10420 | pid == -1 ? 0 : -1 /* cpu */, | |
10421 | -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); | |
708ac5be | 10422 | return pfd >= 0 ? pfd : -errno; |
b2650027 AN |
10423 | } |
10424 | ||
46ed5fc3 AN |
10425 | static int append_to_file(const char *file, const char *fmt, ...) |
10426 | { | |
10427 | int fd, n, err = 0; | |
10428 | va_list ap; | |
01dc26c9 LP |
10429 | char buf[1024]; |
10430 | ||
10431 | va_start(ap, fmt); | |
10432 | n = vsnprintf(buf, sizeof(buf), fmt, ap); | |
10433 | va_end(ap); | |
10434 | ||
10435 | if (n < 0 || n >= sizeof(buf)) | |
10436 | return -EINVAL; | |
46ed5fc3 | 10437 | |
92274e24 | 10438 | fd = open(file, O_WRONLY | O_APPEND | O_CLOEXEC, 0); |
46ed5fc3 AN |
10439 | if (fd < 0) |
10440 | return -errno; | |
10441 | ||
01dc26c9 | 10442 | if (write(fd, buf, n) < 0) |
46ed5fc3 AN |
10443 | err = -errno; |
10444 | ||
10445 | close(fd); | |
10446 | return err; | |
10447 | } | |
10448 | ||
a1ac9fd6 AN |
10449 | #define DEBUGFS "/sys/kernel/debug/tracing" |
10450 | #define TRACEFS "/sys/kernel/tracing" | |
10451 | ||
10452 | static bool use_debugfs(void) | |
10453 | { | |
10454 | static int has_debugfs = -1; | |
10455 | ||
10456 | if (has_debugfs < 0) | |
6a4ab886 | 10457 | has_debugfs = faccessat(AT_FDCWD, DEBUGFS, F_OK, AT_EACCESS) == 0; |
a1ac9fd6 AN |
10458 | |
10459 | return has_debugfs == 1; | |
10460 | } | |
10461 | ||
10462 | static const char *tracefs_path(void) | |
10463 | { | |
10464 | return use_debugfs() ? DEBUGFS : TRACEFS; | |
10465 | } | |
10466 | ||
10467 | static const char *tracefs_kprobe_events(void) | |
10468 | { | |
10469 | return use_debugfs() ? DEBUGFS"/kprobe_events" : TRACEFS"/kprobe_events"; | |
10470 | } | |
10471 | ||
10472 | static const char *tracefs_uprobe_events(void) | |
10473 | { | |
10474 | return use_debugfs() ? DEBUGFS"/uprobe_events" : TRACEFS"/uprobe_events"; | |
10475 | } | |
10476 | ||
8a3fe76f JL |
10477 | static const char *tracefs_available_filter_functions(void) |
10478 | { | |
10479 | return use_debugfs() ? DEBUGFS"/available_filter_functions" | |
10480 | : TRACEFS"/available_filter_functions"; | |
10481 | } | |
10482 | ||
56baeeba JL |
10483 | static const char *tracefs_available_filter_functions_addrs(void) |
10484 | { | |
10485 | return use_debugfs() ? DEBUGFS"/available_filter_functions_addrs" | |
10486 | : TRACEFS"/available_filter_functions_addrs"; | |
10487 | } | |
10488 | ||
46ed5fc3 AN |
10489 | static void gen_kprobe_legacy_event_name(char *buf, size_t buf_sz, |
10490 | const char *kfunc_name, size_t offset) | |
10491 | { | |
51a33c60 | 10492 | static int index = 0; |
2fa07453 | 10493 | int i; |
51a33c60 QW |
10494 | |
10495 | snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx_%d", getpid(), kfunc_name, offset, | |
10496 | __sync_fetch_and_add(&index, 1)); | |
2fa07453 MD |
10497 | |
10498 | /* sanitize binary_path in the probe name */ | |
10499 | for (i = 0; buf[i]; i++) { | |
10500 | if (!isalnum(buf[i])) | |
10501 | buf[i] = '_'; | |
10502 | } | |
46ed5fc3 AN |
10503 | } |
10504 | ||
10505 | static int add_kprobe_event_legacy(const char *probe_name, bool retprobe, | |
10506 | const char *kfunc_name, size_t offset) | |
10507 | { | |
a1ac9fd6 | 10508 | return append_to_file(tracefs_kprobe_events(), "%c:%s/%s %s+0x%zx", |
46ed5fc3 AN |
10509 | retprobe ? 'r' : 'p', |
10510 | retprobe ? "kretprobes" : "kprobes", | |
10511 | probe_name, kfunc_name, offset); | |
10512 | } | |
10513 | ||
10514 | static int remove_kprobe_event_legacy(const char *probe_name, bool retprobe) | |
10515 | { | |
a1ac9fd6 AN |
10516 | return append_to_file(tracefs_kprobe_events(), "-:%s/%s", |
10517 | retprobe ? "kretprobes" : "kprobes", probe_name); | |
46ed5fc3 AN |
10518 | } |
10519 | ||
10520 | static int determine_kprobe_perf_type_legacy(const char *probe_name, bool retprobe) | |
10521 | { | |
10522 | char file[256]; | |
10523 | ||
a1ac9fd6 AN |
10524 | snprintf(file, sizeof(file), "%s/events/%s/%s/id", |
10525 | tracefs_path(), retprobe ? "kretprobes" : "kprobes", probe_name); | |
46ed5fc3 AN |
10526 | |
10527 | return parse_uint_from_file(file, "%d\n"); | |
10528 | } | |
10529 | ||
10530 | static int perf_event_kprobe_open_legacy(const char *probe_name, bool retprobe, | |
10531 | const char *kfunc_name, size_t offset, int pid) | |
ca304b40 | 10532 | { |
813847a3 AN |
10533 | const size_t attr_sz = sizeof(struct perf_event_attr); |
10534 | struct perf_event_attr attr; | |
ca304b40 RDT |
10535 | char errmsg[STRERR_BUFSIZE]; |
10536 | int type, pfd, err; | |
10537 | ||
46ed5fc3 | 10538 | err = add_kprobe_event_legacy(probe_name, retprobe, kfunc_name, offset); |
ca304b40 | 10539 | if (err < 0) { |
46ed5fc3 AN |
10540 | pr_warn("failed to add legacy kprobe event for '%s+0x%zx': %s\n", |
10541 | kfunc_name, offset, | |
ca304b40 RDT |
10542 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
10543 | return err; | |
10544 | } | |
46ed5fc3 | 10545 | type = determine_kprobe_perf_type_legacy(probe_name, retprobe); |
ca304b40 | 10546 | if (type < 0) { |
80940293 | 10547 | err = type; |
46ed5fc3 AN |
10548 | pr_warn("failed to determine legacy kprobe event id for '%s+0x%zx': %s\n", |
10549 | kfunc_name, offset, | |
80940293 CW |
10550 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
10551 | goto err_clean_legacy; | |
ca304b40 | 10552 | } |
813847a3 AN |
10553 | |
10554 | memset(&attr, 0, attr_sz); | |
10555 | attr.size = attr_sz; | |
ca304b40 RDT |
10556 | attr.config = type; |
10557 | attr.type = PERF_TYPE_TRACEPOINT; | |
10558 | ||
10559 | pfd = syscall(__NR_perf_event_open, &attr, | |
10560 | pid < 0 ? -1 : pid, /* pid */ | |
10561 | pid == -1 ? 0 : -1, /* cpu */ | |
10562 | -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); | |
10563 | if (pfd < 0) { | |
10564 | err = -errno; | |
10565 | pr_warn("legacy kprobe perf_event_open() failed: %s\n", | |
10566 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
80940293 | 10567 | goto err_clean_legacy; |
ca304b40 RDT |
10568 | } |
10569 | return pfd; | |
80940293 CW |
10570 | |
10571 | err_clean_legacy: | |
10572 | /* Clear the newly added legacy kprobe_event */ | |
10573 | remove_kprobe_event_legacy(probe_name, retprobe); | |
10574 | return err; | |
ca304b40 RDT |
10575 | } |
10576 | ||
708ac5be AN |
10577 | static const char *arch_specific_syscall_pfx(void) |
10578 | { | |
10579 | #if defined(__x86_64__) | |
10580 | return "x64"; | |
10581 | #elif defined(__i386__) | |
10582 | return "ia32"; | |
10583 | #elif defined(__s390x__) | |
10584 | return "s390x"; | |
10585 | #elif defined(__s390__) | |
10586 | return "s390"; | |
10587 | #elif defined(__arm__) | |
10588 | return "arm"; | |
10589 | #elif defined(__aarch64__) | |
10590 | return "arm64"; | |
10591 | #elif defined(__mips__) | |
10592 | return "mips"; | |
10593 | #elif defined(__riscv) | |
10594 | return "riscv"; | |
64893e83 DM |
10595 | #elif defined(__powerpc__) |
10596 | return "powerpc"; | |
10597 | #elif defined(__powerpc64__) | |
10598 | return "powerpc64"; | |
708ac5be AN |
10599 | #else |
10600 | return NULL; | |
10601 | #endif | |
10602 | } | |
10603 | ||
10604 | static int probe_kern_syscall_wrapper(void) | |
10605 | { | |
10606 | char syscall_name[64]; | |
10607 | const char *ksys_pfx; | |
10608 | ||
10609 | ksys_pfx = arch_specific_syscall_pfx(); | |
10610 | if (!ksys_pfx) | |
10611 | return 0; | |
10612 | ||
10613 | snprintf(syscall_name, sizeof(syscall_name), "__%s_sys_bpf", ksys_pfx); | |
10614 | ||
10615 | if (determine_kprobe_perf_type() >= 0) { | |
10616 | int pfd; | |
10617 | ||
10618 | pfd = perf_event_open_probe(false, false, syscall_name, 0, getpid(), 0); | |
10619 | if (pfd >= 0) | |
10620 | close(pfd); | |
10621 | ||
10622 | return pfd >= 0 ? 1 : 0; | |
10623 | } else { /* legacy mode */ | |
10624 | char probe_name[128]; | |
10625 | ||
10626 | gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), syscall_name, 0); | |
10627 | if (add_kprobe_event_legacy(probe_name, false, syscall_name, 0) < 0) | |
10628 | return 0; | |
10629 | ||
10630 | (void)remove_kprobe_event_legacy(probe_name, false); | |
10631 | return 1; | |
10632 | } | |
10633 | } | |
10634 | ||
da97553e | 10635 | struct bpf_link * |
942025c9 | 10636 | bpf_program__attach_kprobe_opts(const struct bpf_program *prog, |
ac0ed488 | 10637 | const char *func_name, |
47faff37 | 10638 | const struct bpf_kprobe_opts *opts) |
b2650027 | 10639 | { |
47faff37 | 10640 | DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, pe_opts); |
f8b299bc | 10641 | enum probe_attach_mode attach_mode; |
b2650027 | 10642 | char errmsg[STRERR_BUFSIZE]; |
ca304b40 | 10643 | char *legacy_probe = NULL; |
b2650027 | 10644 | struct bpf_link *link; |
46ed5fc3 | 10645 | size_t offset; |
ca304b40 | 10646 | bool retprobe, legacy; |
b2650027 AN |
10647 | int pfd, err; |
10648 | ||
da97553e JO |
10649 | if (!OPTS_VALID(opts, bpf_kprobe_opts)) |
10650 | return libbpf_err_ptr(-EINVAL); | |
10651 | ||
f8b299bc | 10652 | attach_mode = OPTS_GET(opts, attach_mode, PROBE_ATTACH_MODE_DEFAULT); |
da97553e JO |
10653 | retprobe = OPTS_GET(opts, retprobe, false); |
10654 | offset = OPTS_GET(opts, offset, 0); | |
47faff37 | 10655 | pe_opts.bpf_cookie = OPTS_GET(opts, bpf_cookie, 0); |
da97553e | 10656 | |
ca304b40 | 10657 | legacy = determine_kprobe_perf_type() < 0; |
f8b299bc MD |
10658 | switch (attach_mode) { |
10659 | case PROBE_ATTACH_MODE_LEGACY: | |
10660 | legacy = true; | |
10661 | pe_opts.force_ioctl_attach = true; | |
10662 | break; | |
10663 | case PROBE_ATTACH_MODE_PERF: | |
10664 | if (legacy) | |
10665 | return libbpf_err_ptr(-ENOTSUP); | |
10666 | pe_opts.force_ioctl_attach = true; | |
10667 | break; | |
10668 | case PROBE_ATTACH_MODE_LINK: | |
10669 | if (legacy || !kernel_supports(prog->obj, FEAT_PERF_LINK)) | |
10670 | return libbpf_err_ptr(-ENOTSUP); | |
10671 | break; | |
10672 | case PROBE_ATTACH_MODE_DEFAULT: | |
10673 | break; | |
10674 | default: | |
10675 | return libbpf_err_ptr(-EINVAL); | |
10676 | } | |
10677 | ||
ca304b40 RDT |
10678 | if (!legacy) { |
10679 | pfd = perf_event_open_probe(false /* uprobe */, retprobe, | |
10680 | func_name, offset, | |
10681 | -1 /* pid */, 0 /* ref_ctr_off */); | |
10682 | } else { | |
46ed5fc3 AN |
10683 | char probe_name[256]; |
10684 | ||
10685 | gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), | |
10686 | func_name, offset); | |
10687 | ||
71cff670 | 10688 | legacy_probe = strdup(probe_name); |
ca304b40 RDT |
10689 | if (!legacy_probe) |
10690 | return libbpf_err_ptr(-ENOMEM); | |
10691 | ||
46ed5fc3 | 10692 | pfd = perf_event_kprobe_open_legacy(legacy_probe, retprobe, func_name, |
ca304b40 RDT |
10693 | offset, -1 /* pid */); |
10694 | } | |
b2650027 | 10695 | if (pfd < 0) { |
46ed5fc3 AN |
10696 | err = -errno; |
10697 | pr_warn("prog '%s': failed to create %s '%s+0x%zx' perf event: %s\n", | |
10698 | prog->name, retprobe ? "kretprobe" : "kprobe", | |
10699 | func_name, offset, | |
303a2572 AN |
10700 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
10701 | goto err_out; | |
b2650027 | 10702 | } |
47faff37 | 10703 | link = bpf_program__attach_perf_event_opts(prog, pfd, &pe_opts); |
e9fc3ce9 AN |
10704 | err = libbpf_get_error(link); |
10705 | if (err) { | |
b2650027 | 10706 | close(pfd); |
46ed5fc3 AN |
10707 | pr_warn("prog '%s': failed to attach to %s '%s+0x%zx': %s\n", |
10708 | prog->name, retprobe ? "kretprobe" : "kprobe", | |
10709 | func_name, offset, | |
be18010e | 10710 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
80940293 | 10711 | goto err_clean_legacy; |
b2650027 | 10712 | } |
ca304b40 RDT |
10713 | if (legacy) { |
10714 | struct bpf_link_perf *perf_link = container_of(link, struct bpf_link_perf, link); | |
10715 | ||
10716 | perf_link->legacy_probe_name = legacy_probe; | |
46ed5fc3 | 10717 | perf_link->legacy_is_kprobe = true; |
ca304b40 RDT |
10718 | perf_link->legacy_is_retprobe = retprobe; |
10719 | } | |
10720 | ||
b2650027 | 10721 | return link; |
80940293 CW |
10722 | |
10723 | err_clean_legacy: | |
10724 | if (legacy) | |
10725 | remove_kprobe_event_legacy(legacy_probe, retprobe); | |
303a2572 AN |
10726 | err_out: |
10727 | free(legacy_probe); | |
10728 | return libbpf_err_ptr(err); | |
b2650027 AN |
10729 | } |
10730 | ||
942025c9 | 10731 | struct bpf_link *bpf_program__attach_kprobe(const struct bpf_program *prog, |
ac0ed488 JO |
10732 | bool retprobe, |
10733 | const char *func_name) | |
10734 | { | |
da97553e | 10735 | DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts, |
ac0ed488 | 10736 | .retprobe = retprobe, |
da97553e | 10737 | ); |
ac0ed488 JO |
10738 | |
10739 | return bpf_program__attach_kprobe_opts(prog, func_name, &opts); | |
10740 | } | |
10741 | ||
708ac5be AN |
10742 | struct bpf_link *bpf_program__attach_ksyscall(const struct bpf_program *prog, |
10743 | const char *syscall_name, | |
10744 | const struct bpf_ksyscall_opts *opts) | |
10745 | { | |
10746 | LIBBPF_OPTS(bpf_kprobe_opts, kprobe_opts); | |
10747 | char func_name[128]; | |
10748 | ||
10749 | if (!OPTS_VALID(opts, bpf_ksyscall_opts)) | |
10750 | return libbpf_err_ptr(-EINVAL); | |
10751 | ||
10752 | if (kernel_supports(prog->obj, FEAT_SYSCALL_WRAPPER)) { | |
64893e83 DM |
10753 | /* arch_specific_syscall_pfx() should never return NULL here |
10754 | * because it is guarded by kernel_supports(). However, since | |
10755 | * compiler does not know that we have an explicit conditional | |
10756 | * as well. | |
10757 | */ | |
708ac5be | 10758 | snprintf(func_name, sizeof(func_name), "__%s_sys_%s", |
64893e83 | 10759 | arch_specific_syscall_pfx() ? : "", syscall_name); |
708ac5be AN |
10760 | } else { |
10761 | snprintf(func_name, sizeof(func_name), "__se_sys_%s", syscall_name); | |
10762 | } | |
10763 | ||
10764 | kprobe_opts.retprobe = OPTS_GET(opts, retprobe, false); | |
10765 | kprobe_opts.bpf_cookie = OPTS_GET(opts, bpf_cookie, 0); | |
10766 | ||
10767 | return bpf_program__attach_kprobe_opts(prog, func_name, &kprobe_opts); | |
10768 | } | |
10769 | ||
ddc6b049 | 10770 | /* Adapted from perf/util/string.c */ |
e613d1d0 | 10771 | bool glob_match(const char *str, const char *pat) |
ddc6b049 JO |
10772 | { |
10773 | while (*str && *pat && *pat != '*') { | |
10774 | if (*pat == '?') { /* Matches any single character */ | |
10775 | str++; | |
10776 | pat++; | |
10777 | continue; | |
10778 | } | |
10779 | if (*str != *pat) | |
10780 | return false; | |
10781 | str++; | |
10782 | pat++; | |
10783 | } | |
10784 | /* Check wild card */ | |
10785 | if (*pat == '*') { | |
10786 | while (*pat == '*') | |
10787 | pat++; | |
10788 | if (!*pat) /* Tail wild card matches all */ | |
10789 | return true; | |
10790 | while (*str) | |
10791 | if (glob_match(str++, pat)) | |
10792 | return true; | |
10793 | } | |
10794 | return !*str && !*pat; | |
10795 | } | |
10796 | ||
10797 | struct kprobe_multi_resolve { | |
10798 | const char *pattern; | |
10799 | unsigned long *addrs; | |
10800 | size_t cap; | |
10801 | size_t cnt; | |
10802 | }; | |
10803 | ||
8a3fe76f JL |
10804 | struct avail_kallsyms_data { |
10805 | char **syms; | |
10806 | size_t cnt; | |
10807 | struct kprobe_multi_resolve *res; | |
10808 | }; | |
10809 | ||
10810 | static int avail_func_cmp(const void *a, const void *b) | |
10811 | { | |
10812 | return strcmp(*(const char **)a, *(const char **)b); | |
10813 | } | |
10814 | ||
10815 | static int avail_kallsyms_cb(unsigned long long sym_addr, char sym_type, | |
10816 | const char *sym_name, void *ctx) | |
ddc6b049 | 10817 | { |
8a3fe76f JL |
10818 | struct avail_kallsyms_data *data = ctx; |
10819 | struct kprobe_multi_resolve *res = data->res; | |
ddc6b049 JO |
10820 | int err; |
10821 | ||
8a3fe76f | 10822 | if (!bsearch(&sym_name, data->syms, data->cnt, sizeof(*data->syms), avail_func_cmp)) |
ddc6b049 JO |
10823 | return 0; |
10824 | ||
8a3fe76f | 10825 | err = libbpf_ensure_mem((void **)&res->addrs, &res->cap, sizeof(*res->addrs), res->cnt + 1); |
ddc6b049 JO |
10826 | if (err) |
10827 | return err; | |
10828 | ||
8a3fe76f | 10829 | res->addrs[res->cnt++] = (unsigned long)sym_addr; |
ddc6b049 JO |
10830 | return 0; |
10831 | } | |
10832 | ||
8a3fe76f JL |
10833 | static int libbpf_available_kallsyms_parse(struct kprobe_multi_resolve *res) |
10834 | { | |
10835 | const char *available_functions_file = tracefs_available_filter_functions(); | |
10836 | struct avail_kallsyms_data data; | |
10837 | char sym_name[500]; | |
10838 | FILE *f; | |
10839 | int err = 0, ret, i; | |
10840 | char **syms = NULL; | |
10841 | size_t cap = 0, cnt = 0; | |
10842 | ||
10843 | f = fopen(available_functions_file, "re"); | |
10844 | if (!f) { | |
10845 | err = -errno; | |
10846 | pr_warn("failed to open %s: %d\n", available_functions_file, err); | |
10847 | return err; | |
10848 | } | |
10849 | ||
10850 | while (true) { | |
10851 | char *name; | |
10852 | ||
10853 | ret = fscanf(f, "%499s%*[^\n]\n", sym_name); | |
10854 | if (ret == EOF && feof(f)) | |
10855 | break; | |
10856 | ||
10857 | if (ret != 1) { | |
10858 | pr_warn("failed to parse available_filter_functions entry: %d\n", ret); | |
10859 | err = -EINVAL; | |
10860 | goto cleanup; | |
10861 | } | |
10862 | ||
10863 | if (!glob_match(sym_name, res->pattern)) | |
10864 | continue; | |
10865 | ||
10866 | err = libbpf_ensure_mem((void **)&syms, &cap, sizeof(*syms), cnt + 1); | |
10867 | if (err) | |
10868 | goto cleanup; | |
10869 | ||
10870 | name = strdup(sym_name); | |
10871 | if (!name) { | |
10872 | err = -errno; | |
10873 | goto cleanup; | |
10874 | } | |
10875 | ||
10876 | syms[cnt++] = name; | |
10877 | } | |
10878 | ||
10879 | /* no entries found, bail out */ | |
10880 | if (cnt == 0) { | |
10881 | err = -ENOENT; | |
10882 | goto cleanup; | |
10883 | } | |
10884 | ||
10885 | /* sort available functions */ | |
10886 | qsort(syms, cnt, sizeof(*syms), avail_func_cmp); | |
10887 | ||
10888 | data.syms = syms; | |
10889 | data.res = res; | |
10890 | data.cnt = cnt; | |
10891 | libbpf_kallsyms_parse(avail_kallsyms_cb, &data); | |
10892 | ||
10893 | if (res->cnt == 0) | |
10894 | err = -ENOENT; | |
10895 | ||
10896 | cleanup: | |
10897 | for (i = 0; i < cnt; i++) | |
10898 | free((char *)syms[i]); | |
10899 | free(syms); | |
10900 | ||
10901 | fclose(f); | |
10902 | return err; | |
10903 | } | |
10904 | ||
56baeeba JL |
10905 | static bool has_available_filter_functions_addrs(void) |
10906 | { | |
10907 | return access(tracefs_available_filter_functions_addrs(), R_OK) != -1; | |
10908 | } | |
10909 | ||
10910 | static int libbpf_available_kprobes_parse(struct kprobe_multi_resolve *res) | |
10911 | { | |
10912 | const char *available_path = tracefs_available_filter_functions_addrs(); | |
10913 | char sym_name[500]; | |
10914 | FILE *f; | |
10915 | int ret, err = 0; | |
10916 | unsigned long long sym_addr; | |
10917 | ||
10918 | f = fopen(available_path, "re"); | |
10919 | if (!f) { | |
10920 | err = -errno; | |
10921 | pr_warn("failed to open %s: %d\n", available_path, err); | |
10922 | return err; | |
10923 | } | |
10924 | ||
10925 | while (true) { | |
10926 | ret = fscanf(f, "%llx %499s%*[^\n]\n", &sym_addr, sym_name); | |
10927 | if (ret == EOF && feof(f)) | |
10928 | break; | |
10929 | ||
10930 | if (ret != 2) { | |
10931 | pr_warn("failed to parse available_filter_functions_addrs entry: %d\n", | |
10932 | ret); | |
10933 | err = -EINVAL; | |
10934 | goto cleanup; | |
10935 | } | |
10936 | ||
10937 | if (!glob_match(sym_name, res->pattern)) | |
10938 | continue; | |
10939 | ||
10940 | err = libbpf_ensure_mem((void **)&res->addrs, &res->cap, | |
10941 | sizeof(*res->addrs), res->cnt + 1); | |
10942 | if (err) | |
10943 | goto cleanup; | |
10944 | ||
10945 | res->addrs[res->cnt++] = (unsigned long)sym_addr; | |
10946 | } | |
10947 | ||
10948 | if (res->cnt == 0) | |
10949 | err = -ENOENT; | |
10950 | ||
10951 | cleanup: | |
10952 | fclose(f); | |
10953 | return err; | |
10954 | } | |
10955 | ||
ddc6b049 JO |
10956 | struct bpf_link * |
10957 | bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, | |
10958 | const char *pattern, | |
10959 | const struct bpf_kprobe_multi_opts *opts) | |
10960 | { | |
10961 | LIBBPF_OPTS(bpf_link_create_opts, lopts); | |
10962 | struct kprobe_multi_resolve res = { | |
10963 | .pattern = pattern, | |
10964 | }; | |
10965 | struct bpf_link *link = NULL; | |
10966 | char errmsg[STRERR_BUFSIZE]; | |
10967 | const unsigned long *addrs; | |
10968 | int err, link_fd, prog_fd; | |
10969 | const __u64 *cookies; | |
10970 | const char **syms; | |
10971 | bool retprobe; | |
10972 | size_t cnt; | |
10973 | ||
10974 | if (!OPTS_VALID(opts, bpf_kprobe_multi_opts)) | |
10975 | return libbpf_err_ptr(-EINVAL); | |
10976 | ||
10977 | syms = OPTS_GET(opts, syms, false); | |
10978 | addrs = OPTS_GET(opts, addrs, false); | |
10979 | cnt = OPTS_GET(opts, cnt, false); | |
10980 | cookies = OPTS_GET(opts, cookies, false); | |
10981 | ||
10982 | if (!pattern && !addrs && !syms) | |
10983 | return libbpf_err_ptr(-EINVAL); | |
10984 | if (pattern && (addrs || syms || cookies || cnt)) | |
10985 | return libbpf_err_ptr(-EINVAL); | |
10986 | if (!pattern && !cnt) | |
10987 | return libbpf_err_ptr(-EINVAL); | |
10988 | if (addrs && syms) | |
10989 | return libbpf_err_ptr(-EINVAL); | |
10990 | ||
10991 | if (pattern) { | |
56baeeba JL |
10992 | if (has_available_filter_functions_addrs()) |
10993 | err = libbpf_available_kprobes_parse(&res); | |
10994 | else | |
10995 | err = libbpf_available_kallsyms_parse(&res); | |
ddc6b049 JO |
10996 | if (err) |
10997 | goto error; | |
ddc6b049 JO |
10998 | addrs = res.addrs; |
10999 | cnt = res.cnt; | |
11000 | } | |
11001 | ||
11002 | retprobe = OPTS_GET(opts, retprobe, false); | |
11003 | ||
11004 | lopts.kprobe_multi.syms = syms; | |
11005 | lopts.kprobe_multi.addrs = addrs; | |
11006 | lopts.kprobe_multi.cookies = cookies; | |
11007 | lopts.kprobe_multi.cnt = cnt; | |
11008 | lopts.kprobe_multi.flags = retprobe ? BPF_F_KPROBE_MULTI_RETURN : 0; | |
11009 | ||
11010 | link = calloc(1, sizeof(*link)); | |
11011 | if (!link) { | |
11012 | err = -ENOMEM; | |
11013 | goto error; | |
11014 | } | |
11015 | link->detach = &bpf_link__detach_fd; | |
11016 | ||
11017 | prog_fd = bpf_program__fd(prog); | |
11018 | link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_KPROBE_MULTI, &lopts); | |
11019 | if (link_fd < 0) { | |
11020 | err = -errno; | |
11021 | pr_warn("prog '%s': failed to attach: %s\n", | |
11022 | prog->name, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
11023 | goto error; | |
11024 | } | |
11025 | link->fd = link_fd; | |
11026 | free(res.addrs); | |
11027 | return link; | |
11028 | ||
11029 | error: | |
11030 | free(link); | |
11031 | free(res.addrs); | |
11032 | return libbpf_err_ptr(err); | |
11033 | } | |
11034 | ||
4fa5bcfe | 11035 | static int attach_kprobe(const struct bpf_program *prog, long cookie, struct bpf_link **link) |
d7a18ea7 | 11036 | { |
da97553e | 11037 | DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts); |
a2488b5f | 11038 | unsigned long offset = 0; |
d7a18ea7 | 11039 | const char *func_name; |
a2488b5f | 11040 | char *func; |
4fa5bcfe | 11041 | int n; |
d7a18ea7 | 11042 | |
9af8efc4 AN |
11043 | *link = NULL; |
11044 | ||
11045 | /* no auto-attach for SEC("kprobe") and SEC("kretprobe") */ | |
11046 | if (strcmp(prog->sec_name, "kprobe") == 0 || strcmp(prog->sec_name, "kretprobe") == 0) | |
11047 | return 0; | |
11048 | ||
13d35a0c AN |
11049 | opts.retprobe = str_has_pfx(prog->sec_name, "kretprobe/"); |
11050 | if (opts.retprobe) | |
11051 | func_name = prog->sec_name + sizeof("kretprobe/") - 1; | |
11052 | else | |
11053 | func_name = prog->sec_name + sizeof("kprobe/") - 1; | |
d7a18ea7 | 11054 | |
e3f9bc35 | 11055 | n = sscanf(func_name, "%m[a-zA-Z0-9_.]+%li", &func, &offset); |
a2488b5f | 11056 | if (n < 1) { |
a2488b5f | 11057 | pr_warn("kprobe name is invalid: %s\n", func_name); |
4fa5bcfe | 11058 | return -EINVAL; |
a2488b5f AM |
11059 | } |
11060 | if (opts.retprobe && offset != 0) { | |
1f71a468 | 11061 | free(func); |
a2488b5f | 11062 | pr_warn("kretprobes do not support offset specification\n"); |
4fa5bcfe | 11063 | return -EINVAL; |
a2488b5f | 11064 | } |
d7a18ea7 | 11065 | |
a2488b5f | 11066 | opts.offset = offset; |
4fa5bcfe | 11067 | *link = bpf_program__attach_kprobe_opts(prog, func, &opts); |
a2488b5f | 11068 | free(func); |
4fa5bcfe | 11069 | return libbpf_get_error(*link); |
d7a18ea7 AN |
11070 | } |
11071 | ||
708ac5be AN |
11072 | static int attach_ksyscall(const struct bpf_program *prog, long cookie, struct bpf_link **link) |
11073 | { | |
11074 | LIBBPF_OPTS(bpf_ksyscall_opts, opts); | |
11075 | const char *syscall_name; | |
11076 | ||
11077 | *link = NULL; | |
11078 | ||
11079 | /* no auto-attach for SEC("ksyscall") and SEC("kretsyscall") */ | |
11080 | if (strcmp(prog->sec_name, "ksyscall") == 0 || strcmp(prog->sec_name, "kretsyscall") == 0) | |
11081 | return 0; | |
11082 | ||
11083 | opts.retprobe = str_has_pfx(prog->sec_name, "kretsyscall/"); | |
11084 | if (opts.retprobe) | |
11085 | syscall_name = prog->sec_name + sizeof("kretsyscall/") - 1; | |
11086 | else | |
11087 | syscall_name = prog->sec_name + sizeof("ksyscall/") - 1; | |
11088 | ||
11089 | *link = bpf_program__attach_ksyscall(prog, syscall_name, &opts); | |
11090 | return *link ? 0 : -errno; | |
11091 | } | |
11092 | ||
ddc6b049 JO |
11093 | static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link) |
11094 | { | |
11095 | LIBBPF_OPTS(bpf_kprobe_multi_opts, opts); | |
11096 | const char *spec; | |
11097 | char *pattern; | |
11098 | int n; | |
11099 | ||
9af8efc4 AN |
11100 | *link = NULL; |
11101 | ||
11102 | /* no auto-attach for SEC("kprobe.multi") and SEC("kretprobe.multi") */ | |
11103 | if (strcmp(prog->sec_name, "kprobe.multi") == 0 || | |
11104 | strcmp(prog->sec_name, "kretprobe.multi") == 0) | |
11105 | return 0; | |
11106 | ||
ddc6b049 JO |
11107 | opts.retprobe = str_has_pfx(prog->sec_name, "kretprobe.multi/"); |
11108 | if (opts.retprobe) | |
11109 | spec = prog->sec_name + sizeof("kretprobe.multi/") - 1; | |
11110 | else | |
11111 | spec = prog->sec_name + sizeof("kprobe.multi/") - 1; | |
11112 | ||
11113 | n = sscanf(spec, "%m[a-zA-Z0-9_.*?]", &pattern); | |
11114 | if (n < 1) { | |
11115 | pr_warn("kprobe multi pattern is invalid: %s\n", pattern); | |
11116 | return -EINVAL; | |
11117 | } | |
11118 | ||
11119 | *link = bpf_program__attach_kprobe_multi_opts(prog, pattern, &opts); | |
11120 | free(pattern); | |
11121 | return libbpf_get_error(*link); | |
11122 | } | |
11123 | ||
5bfdd32d JO |
11124 | static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link) |
11125 | { | |
11126 | char *probe_type = NULL, *binary_path = NULL, *func_name = NULL; | |
11127 | LIBBPF_OPTS(bpf_uprobe_multi_opts, opts); | |
11128 | int n, ret = -EINVAL; | |
11129 | ||
11130 | *link = NULL; | |
11131 | ||
2147c8d0 | 11132 | n = sscanf(prog->sec_name, "%m[^/]/%m[^:]:%m[^\n]", |
5bfdd32d JO |
11133 | &probe_type, &binary_path, &func_name); |
11134 | switch (n) { | |
11135 | case 1: | |
11136 | /* handle SEC("u[ret]probe") - format is valid, but auto-attach is impossible. */ | |
11137 | ret = 0; | |
11138 | break; | |
11139 | case 3: | |
11140 | opts.retprobe = strcmp(probe_type, "uretprobe.multi") == 0; | |
11141 | *link = bpf_program__attach_uprobe_multi(prog, -1, binary_path, func_name, &opts); | |
11142 | ret = libbpf_get_error(*link); | |
11143 | break; | |
11144 | default: | |
11145 | pr_warn("prog '%s': invalid format of section definition '%s'\n", prog->name, | |
11146 | prog->sec_name); | |
11147 | break; | |
11148 | } | |
11149 | free(probe_type); | |
11150 | free(binary_path); | |
11151 | free(func_name); | |
11152 | return ret; | |
11153 | } | |
11154 | ||
cc10623c AN |
11155 | static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz, |
11156 | const char *binary_path, uint64_t offset) | |
11157 | { | |
11158 | int i; | |
11159 | ||
11160 | snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx", getpid(), binary_path, (size_t)offset); | |
11161 | ||
11162 | /* sanitize binary_path in the probe name */ | |
11163 | for (i = 0; buf[i]; i++) { | |
11164 | if (!isalnum(buf[i])) | |
11165 | buf[i] = '_'; | |
11166 | } | |
11167 | } | |
11168 | ||
11169 | static inline int add_uprobe_event_legacy(const char *probe_name, bool retprobe, | |
11170 | const char *binary_path, size_t offset) | |
11171 | { | |
a1ac9fd6 | 11172 | return append_to_file(tracefs_uprobe_events(), "%c:%s/%s %s:0x%zx", |
cc10623c AN |
11173 | retprobe ? 'r' : 'p', |
11174 | retprobe ? "uretprobes" : "uprobes", | |
11175 | probe_name, binary_path, offset); | |
11176 | } | |
11177 | ||
11178 | static inline int remove_uprobe_event_legacy(const char *probe_name, bool retprobe) | |
11179 | { | |
a1ac9fd6 AN |
11180 | return append_to_file(tracefs_uprobe_events(), "-:%s/%s", |
11181 | retprobe ? "uretprobes" : "uprobes", probe_name); | |
cc10623c AN |
11182 | } |
11183 | ||
11184 | static int determine_uprobe_perf_type_legacy(const char *probe_name, bool retprobe) | |
11185 | { | |
11186 | char file[512]; | |
11187 | ||
a1ac9fd6 AN |
11188 | snprintf(file, sizeof(file), "%s/events/%s/%s/id", |
11189 | tracefs_path(), retprobe ? "uretprobes" : "uprobes", probe_name); | |
cc10623c AN |
11190 | |
11191 | return parse_uint_from_file(file, "%d\n"); | |
11192 | } | |
11193 | ||
11194 | static int perf_event_uprobe_open_legacy(const char *probe_name, bool retprobe, | |
11195 | const char *binary_path, size_t offset, int pid) | |
11196 | { | |
813847a3 | 11197 | const size_t attr_sz = sizeof(struct perf_event_attr); |
cc10623c AN |
11198 | struct perf_event_attr attr; |
11199 | int type, pfd, err; | |
11200 | ||
11201 | err = add_uprobe_event_legacy(probe_name, retprobe, binary_path, offset); | |
11202 | if (err < 0) { | |
11203 | pr_warn("failed to add legacy uprobe event for %s:0x%zx: %d\n", | |
11204 | binary_path, (size_t)offset, err); | |
11205 | return err; | |
11206 | } | |
11207 | type = determine_uprobe_perf_type_legacy(probe_name, retprobe); | |
11208 | if (type < 0) { | |
2655144f | 11209 | err = type; |
cc10623c | 11210 | pr_warn("failed to determine legacy uprobe event id for %s:0x%zx: %d\n", |
2655144f CW |
11211 | binary_path, offset, err); |
11212 | goto err_clean_legacy; | |
cc10623c AN |
11213 | } |
11214 | ||
813847a3 AN |
11215 | memset(&attr, 0, attr_sz); |
11216 | attr.size = attr_sz; | |
cc10623c AN |
11217 | attr.config = type; |
11218 | attr.type = PERF_TYPE_TRACEPOINT; | |
11219 | ||
11220 | pfd = syscall(__NR_perf_event_open, &attr, | |
11221 | pid < 0 ? -1 : pid, /* pid */ | |
11222 | pid == -1 ? 0 : -1, /* cpu */ | |
11223 | -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); | |
11224 | if (pfd < 0) { | |
11225 | err = -errno; | |
11226 | pr_warn("legacy uprobe perf_event_open() failed: %d\n", err); | |
2655144f | 11227 | goto err_clean_legacy; |
cc10623c AN |
11228 | } |
11229 | return pfd; | |
2655144f CW |
11230 | |
11231 | err_clean_legacy: | |
11232 | /* Clear the newly added legacy uprobe_event */ | |
11233 | remove_uprobe_event_legacy(probe_name, retprobe); | |
11234 | return err; | |
cc10623c AN |
11235 | } |
11236 | ||
c44fd845 DM |
11237 | /* Find offset of function name in archive specified by path. Currently |
11238 | * supported are .zip files that do not compress their contents, as used on | |
11239 | * Android in the form of APKs, for example. "file_name" is the name of the ELF | |
11240 | * file inside the archive. "func_name" matches symbol name or name@@LIB for | |
11241 | * library functions. | |
11242 | * | |
11243 | * An overview of the APK format specifically provided here: | |
11244 | * https://en.wikipedia.org/w/index.php?title=Apk_(file_format)&oldid=1139099120#Package_contents | |
11245 | */ | |
11246 | static long elf_find_func_offset_from_archive(const char *archive_path, const char *file_name, | |
11247 | const char *func_name) | |
11248 | { | |
11249 | struct zip_archive *archive; | |
11250 | struct zip_entry entry; | |
11251 | long ret; | |
11252 | Elf *elf; | |
11253 | ||
11254 | archive = zip_archive_open(archive_path); | |
11255 | if (IS_ERR(archive)) { | |
11256 | ret = PTR_ERR(archive); | |
11257 | pr_warn("zip: failed to open %s: %ld\n", archive_path, ret); | |
11258 | return ret; | |
11259 | } | |
11260 | ||
11261 | ret = zip_archive_find_entry(archive, file_name, &entry); | |
11262 | if (ret) { | |
11263 | pr_warn("zip: could not find archive member %s in %s: %ld\n", file_name, | |
11264 | archive_path, ret); | |
11265 | goto out; | |
11266 | } | |
11267 | pr_debug("zip: found entry for %s in %s at 0x%lx\n", file_name, archive_path, | |
11268 | (unsigned long)entry.data_offset); | |
11269 | ||
11270 | if (entry.compression) { | |
11271 | pr_warn("zip: entry %s of %s is compressed and cannot be handled\n", file_name, | |
11272 | archive_path); | |
11273 | ret = -LIBBPF_ERRNO__FORMAT; | |
11274 | goto out; | |
11275 | } | |
11276 | ||
11277 | elf = elf_memory((void *)entry.data, entry.data_length); | |
11278 | if (!elf) { | |
11279 | pr_warn("elf: could not read elf file %s from %s: %s\n", file_name, archive_path, | |
11280 | elf_errmsg(-1)); | |
11281 | ret = -LIBBPF_ERRNO__LIBELF; | |
11282 | goto out; | |
11283 | } | |
11284 | ||
11285 | ret = elf_find_func_offset(elf, file_name, func_name); | |
11286 | if (ret > 0) { | |
11287 | pr_debug("elf: symbol address match for %s of %s in %s: 0x%x + 0x%lx = 0x%lx\n", | |
11288 | func_name, file_name, archive_path, entry.data_offset, ret, | |
11289 | ret + entry.data_offset); | |
11290 | ret += entry.data_offset; | |
11291 | } | |
11292 | elf_end(elf); | |
11293 | ||
11294 | out: | |
11295 | zip_archive_close(archive); | |
11296 | return ret; | |
11297 | } | |
11298 | ||
56818931 IL |
11299 | static const char *arch_specific_lib_paths(void) |
11300 | { | |
11301 | /* | |
11302 | * Based on https://packages.debian.org/sid/libc6. | |
11303 | * | |
11304 | * Assume that the traced program is built for the same architecture | |
11305 | * as libbpf, which should cover the vast majority of cases. | |
11306 | */ | |
11307 | #if defined(__x86_64__) | |
11308 | return "/lib/x86_64-linux-gnu"; | |
11309 | #elif defined(__i386__) | |
11310 | return "/lib/i386-linux-gnu"; | |
11311 | #elif defined(__s390x__) | |
11312 | return "/lib/s390x-linux-gnu"; | |
11313 | #elif defined(__s390__) | |
11314 | return "/lib/s390-linux-gnu"; | |
11315 | #elif defined(__arm__) && defined(__SOFTFP__) | |
11316 | return "/lib/arm-linux-gnueabi"; | |
11317 | #elif defined(__arm__) && !defined(__SOFTFP__) | |
11318 | return "/lib/arm-linux-gnueabihf"; | |
11319 | #elif defined(__aarch64__) | |
11320 | return "/lib/aarch64-linux-gnu"; | |
11321 | #elif defined(__mips__) && defined(__MIPSEL__) && _MIPS_SZLONG == 64 | |
11322 | return "/lib/mips64el-linux-gnuabi64"; | |
11323 | #elif defined(__mips__) && defined(__MIPSEL__) && _MIPS_SZLONG == 32 | |
11324 | return "/lib/mipsel-linux-gnu"; | |
11325 | #elif defined(__powerpc64__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ | |
11326 | return "/lib/powerpc64le-linux-gnu"; | |
11327 | #elif defined(__sparc__) && defined(__arch64__) | |
11328 | return "/lib/sparc64-linux-gnu"; | |
11329 | #elif defined(__riscv) && __riscv_xlen == 64 | |
11330 | return "/lib/riscv64-linux-gnu"; | |
11331 | #else | |
11332 | return NULL; | |
11333 | #endif | |
11334 | } | |
11335 | ||
1ce3a60e AM |
11336 | /* Get full path to program/shared library. */ |
11337 | static int resolve_full_path(const char *file, char *result, size_t result_sz) | |
11338 | { | |
56818931 | 11339 | const char *search_paths[3] = {}; |
9e32084e | 11340 | int i, perm; |
1ce3a60e | 11341 | |
a1c9d61b | 11342 | if (str_has_sfx(file, ".so") || strstr(file, ".so.")) { |
1ce3a60e AM |
11343 | search_paths[0] = getenv("LD_LIBRARY_PATH"); |
11344 | search_paths[1] = "/usr/lib64:/usr/lib"; | |
56818931 | 11345 | search_paths[2] = arch_specific_lib_paths(); |
9e32084e | 11346 | perm = R_OK; |
1ce3a60e AM |
11347 | } else { |
11348 | search_paths[0] = getenv("PATH"); | |
11349 | search_paths[1] = "/usr/bin:/usr/sbin"; | |
9e32084e | 11350 | perm = R_OK | X_OK; |
1ce3a60e AM |
11351 | } |
11352 | ||
11353 | for (i = 0; i < ARRAY_SIZE(search_paths); i++) { | |
11354 | const char *s; | |
11355 | ||
11356 | if (!search_paths[i]) | |
11357 | continue; | |
11358 | for (s = search_paths[i]; s != NULL; s = strchr(s, ':')) { | |
11359 | char *next_path; | |
11360 | int seg_len; | |
11361 | ||
11362 | if (s[0] == ':') | |
11363 | s++; | |
11364 | next_path = strchr(s, ':'); | |
11365 | seg_len = next_path ? next_path - s : strlen(s); | |
11366 | if (!seg_len) | |
11367 | continue; | |
11368 | snprintf(result, result_sz, "%.*s/%s", seg_len, s, file); | |
9e32084e | 11369 | /* ensure it has required permissions */ |
6a4ab886 | 11370 | if (faccessat(AT_FDCWD, result, perm, AT_EACCESS) < 0) |
1ce3a60e AM |
11371 | continue; |
11372 | pr_debug("resolved '%s' to '%s'\n", file, result); | |
11373 | return 0; | |
11374 | } | |
11375 | } | |
11376 | return -ENOENT; | |
11377 | } | |
11378 | ||
3140cf12 JO |
11379 | struct bpf_link * |
11380 | bpf_program__attach_uprobe_multi(const struct bpf_program *prog, | |
11381 | pid_t pid, | |
11382 | const char *path, | |
11383 | const char *func_pattern, | |
11384 | const struct bpf_uprobe_multi_opts *opts) | |
11385 | { | |
11386 | const unsigned long *ref_ctr_offsets = NULL, *offsets = NULL; | |
11387 | LIBBPF_OPTS(bpf_link_create_opts, lopts); | |
11388 | unsigned long *resolved_offsets = NULL; | |
11389 | int err = 0, link_fd, prog_fd; | |
11390 | struct bpf_link *link = NULL; | |
11391 | char errmsg[STRERR_BUFSIZE]; | |
11392 | char full_path[PATH_MAX]; | |
11393 | const __u64 *cookies; | |
11394 | const char **syms; | |
11395 | size_t cnt; | |
11396 | ||
11397 | if (!OPTS_VALID(opts, bpf_uprobe_multi_opts)) | |
11398 | return libbpf_err_ptr(-EINVAL); | |
11399 | ||
11400 | syms = OPTS_GET(opts, syms, NULL); | |
11401 | offsets = OPTS_GET(opts, offsets, NULL); | |
11402 | ref_ctr_offsets = OPTS_GET(opts, ref_ctr_offsets, NULL); | |
11403 | cookies = OPTS_GET(opts, cookies, NULL); | |
11404 | cnt = OPTS_GET(opts, cnt, 0); | |
11405 | ||
11406 | /* | |
11407 | * User can specify 2 mutually exclusive set of inputs: | |
11408 | * | |
11409 | * 1) use only path/func_pattern/pid arguments | |
11410 | * | |
11411 | * 2) use path/pid with allowed combinations of: | |
11412 | * syms/offsets/ref_ctr_offsets/cookies/cnt | |
11413 | * | |
11414 | * - syms and offsets are mutually exclusive | |
11415 | * - ref_ctr_offsets and cookies are optional | |
11416 | * | |
11417 | * Any other usage results in error. | |
11418 | */ | |
11419 | ||
11420 | if (!path) | |
11421 | return libbpf_err_ptr(-EINVAL); | |
11422 | if (!func_pattern && cnt == 0) | |
11423 | return libbpf_err_ptr(-EINVAL); | |
11424 | ||
11425 | if (func_pattern) { | |
11426 | if (syms || offsets || ref_ctr_offsets || cookies || cnt) | |
11427 | return libbpf_err_ptr(-EINVAL); | |
11428 | } else { | |
11429 | if (!!syms == !!offsets) | |
11430 | return libbpf_err_ptr(-EINVAL); | |
11431 | } | |
11432 | ||
11433 | if (func_pattern) { | |
11434 | if (!strchr(path, '/')) { | |
11435 | err = resolve_full_path(path, full_path, sizeof(full_path)); | |
11436 | if (err) { | |
11437 | pr_warn("prog '%s': failed to resolve full path for '%s': %d\n", | |
11438 | prog->name, path, err); | |
11439 | return libbpf_err_ptr(err); | |
11440 | } | |
11441 | path = full_path; | |
11442 | } | |
11443 | ||
11444 | err = elf_resolve_pattern_offsets(path, func_pattern, | |
11445 | &resolved_offsets, &cnt); | |
11446 | if (err < 0) | |
11447 | return libbpf_err_ptr(err); | |
11448 | offsets = resolved_offsets; | |
11449 | } else if (syms) { | |
11450 | err = elf_resolve_syms_offsets(path, cnt, syms, &resolved_offsets); | |
11451 | if (err < 0) | |
11452 | return libbpf_err_ptr(err); | |
11453 | offsets = resolved_offsets; | |
11454 | } | |
11455 | ||
11456 | lopts.uprobe_multi.path = path; | |
11457 | lopts.uprobe_multi.offsets = offsets; | |
11458 | lopts.uprobe_multi.ref_ctr_offsets = ref_ctr_offsets; | |
11459 | lopts.uprobe_multi.cookies = cookies; | |
11460 | lopts.uprobe_multi.cnt = cnt; | |
11461 | lopts.uprobe_multi.flags = OPTS_GET(opts, retprobe, false) ? BPF_F_UPROBE_MULTI_RETURN : 0; | |
11462 | ||
11463 | if (pid == 0) | |
11464 | pid = getpid(); | |
11465 | if (pid > 0) | |
11466 | lopts.uprobe_multi.pid = pid; | |
11467 | ||
11468 | link = calloc(1, sizeof(*link)); | |
11469 | if (!link) { | |
11470 | err = -ENOMEM; | |
11471 | goto error; | |
11472 | } | |
11473 | link->detach = &bpf_link__detach_fd; | |
11474 | ||
11475 | prog_fd = bpf_program__fd(prog); | |
11476 | link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_UPROBE_MULTI, &lopts); | |
11477 | if (link_fd < 0) { | |
11478 | err = -errno; | |
11479 | pr_warn("prog '%s': failed to attach multi-uprobe: %s\n", | |
11480 | prog->name, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
11481 | goto error; | |
11482 | } | |
11483 | link->fd = link_fd; | |
11484 | free(resolved_offsets); | |
11485 | return link; | |
11486 | ||
11487 | error: | |
11488 | free(resolved_offsets); | |
11489 | free(link); | |
11490 | return libbpf_err_ptr(err); | |
11491 | } | |
11492 | ||
47faff37 | 11493 | LIBBPF_API struct bpf_link * |
942025c9 | 11494 | bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, |
47faff37 AN |
11495 | const char *binary_path, size_t func_offset, |
11496 | const struct bpf_uprobe_opts *opts) | |
b2650027 | 11497 | { |
c44fd845 | 11498 | const char *archive_path = NULL, *archive_sep = NULL; |
cc10623c | 11499 | char errmsg[STRERR_BUFSIZE], *legacy_probe = NULL; |
c44fd845 | 11500 | DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, pe_opts); |
f8b299bc | 11501 | enum probe_attach_mode attach_mode; |
c44fd845 | 11502 | char full_path[PATH_MAX]; |
b2650027 | 11503 | struct bpf_link *link; |
5e3b8356 | 11504 | size_t ref_ctr_off; |
b2650027 | 11505 | int pfd, err; |
cc10623c | 11506 | bool retprobe, legacy; |
433966e3 | 11507 | const char *func_name; |
47faff37 AN |
11508 | |
11509 | if (!OPTS_VALID(opts, bpf_uprobe_opts)) | |
11510 | return libbpf_err_ptr(-EINVAL); | |
11511 | ||
f8b299bc | 11512 | attach_mode = OPTS_GET(opts, attach_mode, PROBE_ATTACH_MODE_DEFAULT); |
47faff37 | 11513 | retprobe = OPTS_GET(opts, retprobe, false); |
5e3b8356 | 11514 | ref_ctr_off = OPTS_GET(opts, ref_ctr_offset, 0); |
47faff37 | 11515 | pe_opts.bpf_cookie = OPTS_GET(opts, bpf_cookie, 0); |
b2650027 | 11516 | |
8ed2f5a6 HC |
11517 | if (!binary_path) |
11518 | return libbpf_err_ptr(-EINVAL); | |
11519 | ||
c44fd845 DM |
11520 | /* Check if "binary_path" refers to an archive. */ |
11521 | archive_sep = strstr(binary_path, "!/"); | |
11522 | if (archive_sep) { | |
11523 | full_path[0] = '\0'; | |
11524 | libbpf_strlcpy(full_path, binary_path, | |
11525 | min(sizeof(full_path), (size_t)(archive_sep - binary_path + 1))); | |
11526 | archive_path = full_path; | |
11527 | binary_path = archive_sep + 2; | |
11528 | } else if (!strchr(binary_path, '/')) { | |
11529 | err = resolve_full_path(binary_path, full_path, sizeof(full_path)); | |
1ce3a60e | 11530 | if (err) { |
2e4913e0 AN |
11531 | pr_warn("prog '%s': failed to resolve full path for '%s': %d\n", |
11532 | prog->name, binary_path, err); | |
1ce3a60e AM |
11533 | return libbpf_err_ptr(err); |
11534 | } | |
c44fd845 | 11535 | binary_path = full_path; |
1ce3a60e | 11536 | } |
433966e3 AM |
11537 | func_name = OPTS_GET(opts, func_name, NULL); |
11538 | if (func_name) { | |
11539 | long sym_off; | |
11540 | ||
c44fd845 DM |
11541 | if (archive_path) { |
11542 | sym_off = elf_find_func_offset_from_archive(archive_path, binary_path, | |
11543 | func_name); | |
11544 | binary_path = archive_path; | |
11545 | } else { | |
11546 | sym_off = elf_find_func_offset_from_file(binary_path, func_name); | |
11547 | } | |
433966e3 AM |
11548 | if (sym_off < 0) |
11549 | return libbpf_err_ptr(sym_off); | |
11550 | func_offset += sym_off; | |
11551 | } | |
1ce3a60e | 11552 | |
cc10623c | 11553 | legacy = determine_uprobe_perf_type() < 0; |
f8b299bc MD |
11554 | switch (attach_mode) { |
11555 | case PROBE_ATTACH_MODE_LEGACY: | |
11556 | legacy = true; | |
11557 | pe_opts.force_ioctl_attach = true; | |
11558 | break; | |
11559 | case PROBE_ATTACH_MODE_PERF: | |
11560 | if (legacy) | |
11561 | return libbpf_err_ptr(-ENOTSUP); | |
11562 | pe_opts.force_ioctl_attach = true; | |
11563 | break; | |
11564 | case PROBE_ATTACH_MODE_LINK: | |
11565 | if (legacy || !kernel_supports(prog->obj, FEAT_PERF_LINK)) | |
11566 | return libbpf_err_ptr(-ENOTSUP); | |
11567 | break; | |
11568 | case PROBE_ATTACH_MODE_DEFAULT: | |
11569 | break; | |
11570 | default: | |
11571 | return libbpf_err_ptr(-EINVAL); | |
11572 | } | |
11573 | ||
cc10623c AN |
11574 | if (!legacy) { |
11575 | pfd = perf_event_open_probe(true /* uprobe */, retprobe, binary_path, | |
11576 | func_offset, pid, ref_ctr_off); | |
11577 | } else { | |
1ce3a60e | 11578 | char probe_name[PATH_MAX + 64]; |
cc10623c AN |
11579 | |
11580 | if (ref_ctr_off) | |
11581 | return libbpf_err_ptr(-EINVAL); | |
11582 | ||
11583 | gen_uprobe_legacy_event_name(probe_name, sizeof(probe_name), | |
11584 | binary_path, func_offset); | |
11585 | ||
11586 | legacy_probe = strdup(probe_name); | |
11587 | if (!legacy_probe) | |
11588 | return libbpf_err_ptr(-ENOMEM); | |
11589 | ||
11590 | pfd = perf_event_uprobe_open_legacy(legacy_probe, retprobe, | |
11591 | binary_path, func_offset, pid); | |
11592 | } | |
b2650027 | 11593 | if (pfd < 0) { |
cc10623c | 11594 | err = -errno; |
52109584 AN |
11595 | pr_warn("prog '%s': failed to create %s '%s:0x%zx' perf event: %s\n", |
11596 | prog->name, retprobe ? "uretprobe" : "uprobe", | |
be18010e | 11597 | binary_path, func_offset, |
cc10623c AN |
11598 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
11599 | goto err_out; | |
b2650027 | 11600 | } |
cc10623c | 11601 | |
47faff37 | 11602 | link = bpf_program__attach_perf_event_opts(prog, pfd, &pe_opts); |
e9fc3ce9 AN |
11603 | err = libbpf_get_error(link); |
11604 | if (err) { | |
b2650027 | 11605 | close(pfd); |
52109584 AN |
11606 | pr_warn("prog '%s': failed to attach to %s '%s:0x%zx': %s\n", |
11607 | prog->name, retprobe ? "uretprobe" : "uprobe", | |
be18010e KW |
11608 | binary_path, func_offset, |
11609 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
2655144f | 11610 | goto err_clean_legacy; |
cc10623c AN |
11611 | } |
11612 | if (legacy) { | |
11613 | struct bpf_link_perf *perf_link = container_of(link, struct bpf_link_perf, link); | |
11614 | ||
11615 | perf_link->legacy_probe_name = legacy_probe; | |
11616 | perf_link->legacy_is_kprobe = false; | |
11617 | perf_link->legacy_is_retprobe = retprobe; | |
b2650027 AN |
11618 | } |
11619 | return link; | |
2655144f CW |
11620 | |
11621 | err_clean_legacy: | |
11622 | if (legacy) | |
11623 | remove_uprobe_event_legacy(legacy_probe, retprobe); | |
cc10623c AN |
11624 | err_out: |
11625 | free(legacy_probe); | |
11626 | return libbpf_err_ptr(err); | |
b2650027 AN |
11627 | } |
11628 | ||
39f8dc43 AM |
11629 | /* Format of u[ret]probe section definition supporting auto-attach: |
11630 | * u[ret]probe/binary:function[+offset] | |
11631 | * | |
11632 | * binary can be an absolute/relative path or a filename; the latter is resolved to a | |
11633 | * full binary path via bpf_program__attach_uprobe_opts. | |
11634 | * | |
11635 | * Specifying uprobe+ ensures we carry out strict matching; either "uprobe" must be | |
11636 | * specified (and auto-attach is not possible) or the above format is specified for | |
11637 | * auto-attach. | |
11638 | */ | |
11639 | static int attach_uprobe(const struct bpf_program *prog, long cookie, struct bpf_link **link) | |
11640 | { | |
11641 | DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts); | |
2147c8d0 HC |
11642 | char *probe_type = NULL, *binary_path = NULL, *func_name = NULL, *func_off; |
11643 | int n, c, ret = -EINVAL; | |
90db26e6 | 11644 | long offset = 0; |
39f8dc43 AM |
11645 | |
11646 | *link = NULL; | |
11647 | ||
2147c8d0 HC |
11648 | n = sscanf(prog->sec_name, "%m[^/]/%m[^:]:%m[^\n]", |
11649 | &probe_type, &binary_path, &func_name); | |
90db26e6 AM |
11650 | switch (n) { |
11651 | case 1: | |
11652 | /* handle SEC("u[ret]probe") - format is valid, but auto-attach is impossible. */ | |
11653 | ret = 0; | |
11654 | break; | |
11655 | case 2: | |
11656 | pr_warn("prog '%s': section '%s' missing ':function[+offset]' specification\n", | |
11657 | prog->name, prog->sec_name); | |
11658 | break; | |
11659 | case 3: | |
2147c8d0 HC |
11660 | /* check if user specifies `+offset`, if yes, this should be |
11661 | * the last part of the string, make sure sscanf read to EOL | |
11662 | */ | |
11663 | func_off = strrchr(func_name, '+'); | |
11664 | if (func_off) { | |
11665 | n = sscanf(func_off, "+%li%n", &offset, &c); | |
11666 | if (n == 1 && *(func_off + c) == '\0') | |
11667 | func_off[0] = '\0'; | |
11668 | else | |
11669 | offset = 0; | |
11670 | } | |
c4cac71f DK |
11671 | opts.retprobe = strcmp(probe_type, "uretprobe") == 0 || |
11672 | strcmp(probe_type, "uretprobe.s") == 0; | |
90db26e6 AM |
11673 | if (opts.retprobe && offset != 0) { |
11674 | pr_warn("prog '%s': uretprobes do not support offset specification\n", | |
11675 | prog->name); | |
11676 | break; | |
11677 | } | |
11678 | opts.func_name = func_name; | |
11679 | *link = bpf_program__attach_uprobe_opts(prog, -1, binary_path, offset, &opts); | |
11680 | ret = libbpf_get_error(*link); | |
11681 | break; | |
11682 | default: | |
11683 | pr_warn("prog '%s': invalid format of section definition '%s'\n", prog->name, | |
39f8dc43 | 11684 | prog->sec_name); |
90db26e6 | 11685 | break; |
39f8dc43 | 11686 | } |
90db26e6 AM |
11687 | free(probe_type); |
11688 | free(binary_path); | |
11689 | free(func_name); | |
39f8dc43 | 11690 | |
90db26e6 | 11691 | return ret; |
39f8dc43 AM |
11692 | } |
11693 | ||
942025c9 | 11694 | struct bpf_link *bpf_program__attach_uprobe(const struct bpf_program *prog, |
47faff37 AN |
11695 | bool retprobe, pid_t pid, |
11696 | const char *binary_path, | |
11697 | size_t func_offset) | |
11698 | { | |
11699 | DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts, .retprobe = retprobe); | |
11700 | ||
11701 | return bpf_program__attach_uprobe_opts(prog, pid, binary_path, func_offset, &opts); | |
11702 | } | |
11703 | ||
2e4913e0 AN |
11704 | struct bpf_link *bpf_program__attach_usdt(const struct bpf_program *prog, |
11705 | pid_t pid, const char *binary_path, | |
11706 | const char *usdt_provider, const char *usdt_name, | |
11707 | const struct bpf_usdt_opts *opts) | |
11708 | { | |
11709 | char resolved_path[512]; | |
11710 | struct bpf_object *obj = prog->obj; | |
11711 | struct bpf_link *link; | |
5af25a41 | 11712 | __u64 usdt_cookie; |
2e4913e0 AN |
11713 | int err; |
11714 | ||
11715 | if (!OPTS_VALID(opts, bpf_uprobe_opts)) | |
11716 | return libbpf_err_ptr(-EINVAL); | |
11717 | ||
11718 | if (bpf_program__fd(prog) < 0) { | |
11719 | pr_warn("prog '%s': can't attach BPF program w/o FD (did you load it?)\n", | |
11720 | prog->name); | |
11721 | return libbpf_err_ptr(-EINVAL); | |
11722 | } | |
11723 | ||
8ed2f5a6 HC |
11724 | if (!binary_path) |
11725 | return libbpf_err_ptr(-EINVAL); | |
11726 | ||
2e4913e0 AN |
11727 | if (!strchr(binary_path, '/')) { |
11728 | err = resolve_full_path(binary_path, resolved_path, sizeof(resolved_path)); | |
11729 | if (err) { | |
11730 | pr_warn("prog '%s': failed to resolve full path for '%s': %d\n", | |
11731 | prog->name, binary_path, err); | |
11732 | return libbpf_err_ptr(err); | |
11733 | } | |
11734 | binary_path = resolved_path; | |
11735 | } | |
11736 | ||
11737 | /* USDT manager is instantiated lazily on first USDT attach. It will | |
11738 | * be destroyed together with BPF object in bpf_object__close(). | |
11739 | */ | |
11740 | if (IS_ERR(obj->usdt_man)) | |
11741 | return libbpf_ptr(obj->usdt_man); | |
11742 | if (!obj->usdt_man) { | |
11743 | obj->usdt_man = usdt_manager_new(obj); | |
11744 | if (IS_ERR(obj->usdt_man)) | |
11745 | return libbpf_ptr(obj->usdt_man); | |
11746 | } | |
11747 | ||
11748 | usdt_cookie = OPTS_GET(opts, usdt_cookie, 0); | |
11749 | link = usdt_manager_attach_usdt(obj->usdt_man, prog, pid, binary_path, | |
e3ba8e4e | 11750 | usdt_provider, usdt_name, usdt_cookie); |
2e4913e0 AN |
11751 | err = libbpf_get_error(link); |
11752 | if (err) | |
11753 | return libbpf_err_ptr(err); | |
11754 | return link; | |
11755 | } | |
11756 | ||
11757 | static int attach_usdt(const struct bpf_program *prog, long cookie, struct bpf_link **link) | |
11758 | { | |
11759 | char *path = NULL, *provider = NULL, *name = NULL; | |
11760 | const char *sec_name; | |
11761 | int n, err; | |
11762 | ||
11763 | sec_name = bpf_program__section_name(prog); | |
11764 | if (strcmp(sec_name, "usdt") == 0) { | |
11765 | /* no auto-attach for just SEC("usdt") */ | |
11766 | *link = NULL; | |
11767 | return 0; | |
11768 | } | |
11769 | ||
11770 | n = sscanf(sec_name, "usdt/%m[^:]:%m[^:]:%m[^:]", &path, &provider, &name); | |
11771 | if (n != 3) { | |
11772 | pr_warn("invalid section '%s', expected SEC(\"usdt/<path>:<provider>:<name>\")\n", | |
11773 | sec_name); | |
11774 | err = -EINVAL; | |
11775 | } else { | |
11776 | *link = bpf_program__attach_usdt(prog, -1 /* any process */, path, | |
11777 | provider, name, NULL); | |
11778 | err = libbpf_get_error(*link); | |
11779 | } | |
11780 | free(path); | |
11781 | free(provider); | |
11782 | free(name); | |
11783 | return err; | |
11784 | } | |
11785 | ||
f6de59c1 AN |
11786 | static int determine_tracepoint_id(const char *tp_category, |
11787 | const char *tp_name) | |
11788 | { | |
11789 | char file[PATH_MAX]; | |
11790 | int ret; | |
11791 | ||
a1ac9fd6 AN |
11792 | ret = snprintf(file, sizeof(file), "%s/events/%s/%s/id", |
11793 | tracefs_path(), tp_category, tp_name); | |
f6de59c1 AN |
11794 | if (ret < 0) |
11795 | return -errno; | |
11796 | if (ret >= sizeof(file)) { | |
11797 | pr_debug("tracepoint %s/%s path is too long\n", | |
11798 | tp_category, tp_name); | |
11799 | return -E2BIG; | |
11800 | } | |
11801 | return parse_uint_from_file(file, "%d\n"); | |
11802 | } | |
11803 | ||
11804 | static int perf_event_open_tracepoint(const char *tp_category, | |
11805 | const char *tp_name) | |
11806 | { | |
813847a3 AN |
11807 | const size_t attr_sz = sizeof(struct perf_event_attr); |
11808 | struct perf_event_attr attr; | |
f6de59c1 AN |
11809 | char errmsg[STRERR_BUFSIZE]; |
11810 | int tp_id, pfd, err; | |
11811 | ||
11812 | tp_id = determine_tracepoint_id(tp_category, tp_name); | |
11813 | if (tp_id < 0) { | |
be18010e KW |
11814 | pr_warn("failed to determine tracepoint '%s/%s' perf event ID: %s\n", |
11815 | tp_category, tp_name, | |
11816 | libbpf_strerror_r(tp_id, errmsg, sizeof(errmsg))); | |
f6de59c1 AN |
11817 | return tp_id; |
11818 | } | |
11819 | ||
813847a3 | 11820 | memset(&attr, 0, attr_sz); |
f6de59c1 | 11821 | attr.type = PERF_TYPE_TRACEPOINT; |
813847a3 | 11822 | attr.size = attr_sz; |
f6de59c1 AN |
11823 | attr.config = tp_id; |
11824 | ||
11825 | pfd = syscall(__NR_perf_event_open, &attr, -1 /* pid */, 0 /* cpu */, | |
11826 | -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); | |
11827 | if (pfd < 0) { | |
11828 | err = -errno; | |
be18010e KW |
11829 | pr_warn("tracepoint '%s/%s' perf_event_open() failed: %s\n", |
11830 | tp_category, tp_name, | |
11831 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
f6de59c1 AN |
11832 | return err; |
11833 | } | |
11834 | return pfd; | |
11835 | } | |
11836 | ||
942025c9 | 11837 | struct bpf_link *bpf_program__attach_tracepoint_opts(const struct bpf_program *prog, |
47faff37 AN |
11838 | const char *tp_category, |
11839 | const char *tp_name, | |
11840 | const struct bpf_tracepoint_opts *opts) | |
f6de59c1 | 11841 | { |
47faff37 | 11842 | DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, pe_opts); |
f6de59c1 AN |
11843 | char errmsg[STRERR_BUFSIZE]; |
11844 | struct bpf_link *link; | |
11845 | int pfd, err; | |
11846 | ||
47faff37 AN |
11847 | if (!OPTS_VALID(opts, bpf_tracepoint_opts)) |
11848 | return libbpf_err_ptr(-EINVAL); | |
11849 | ||
11850 | pe_opts.bpf_cookie = OPTS_GET(opts, bpf_cookie, 0); | |
11851 | ||
f6de59c1 AN |
11852 | pfd = perf_event_open_tracepoint(tp_category, tp_name); |
11853 | if (pfd < 0) { | |
52109584 AN |
11854 | pr_warn("prog '%s': failed to create tracepoint '%s/%s' perf event: %s\n", |
11855 | prog->name, tp_category, tp_name, | |
be18010e | 11856 | libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
e9fc3ce9 | 11857 | return libbpf_err_ptr(pfd); |
f6de59c1 | 11858 | } |
47faff37 | 11859 | link = bpf_program__attach_perf_event_opts(prog, pfd, &pe_opts); |
e9fc3ce9 AN |
11860 | err = libbpf_get_error(link); |
11861 | if (err) { | |
f6de59c1 | 11862 | close(pfd); |
52109584 AN |
11863 | pr_warn("prog '%s': failed to attach to tracepoint '%s/%s': %s\n", |
11864 | prog->name, tp_category, tp_name, | |
be18010e | 11865 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
e9fc3ce9 | 11866 | return libbpf_err_ptr(err); |
f6de59c1 AN |
11867 | } |
11868 | return link; | |
11869 | } | |
11870 | ||
942025c9 | 11871 | struct bpf_link *bpf_program__attach_tracepoint(const struct bpf_program *prog, |
47faff37 AN |
11872 | const char *tp_category, |
11873 | const char *tp_name) | |
11874 | { | |
11875 | return bpf_program__attach_tracepoint_opts(prog, tp_category, tp_name, NULL); | |
11876 | } | |
11877 | ||
4fa5bcfe | 11878 | static int attach_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link) |
d7a18ea7 AN |
11879 | { |
11880 | char *sec_name, *tp_cat, *tp_name; | |
d7a18ea7 | 11881 | |
9af8efc4 AN |
11882 | *link = NULL; |
11883 | ||
11884 | /* no auto-attach for SEC("tp") or SEC("tracepoint") */ | |
11885 | if (strcmp(prog->sec_name, "tp") == 0 || strcmp(prog->sec_name, "tracepoint") == 0) | |
11886 | return 0; | |
11887 | ||
ac6a6586 AN |
11888 | sec_name = strdup(prog->sec_name); |
11889 | if (!sec_name) | |
11890 | return -ENOMEM; | |
11891 | ||
13d35a0c AN |
11892 | /* extract "tp/<category>/<name>" or "tracepoint/<category>/<name>" */ |
11893 | if (str_has_pfx(prog->sec_name, "tp/")) | |
11894 | tp_cat = sec_name + sizeof("tp/") - 1; | |
11895 | else | |
11896 | tp_cat = sec_name + sizeof("tracepoint/") - 1; | |
d7a18ea7 AN |
11897 | tp_name = strchr(tp_cat, '/'); |
11898 | if (!tp_name) { | |
e9fc3ce9 | 11899 | free(sec_name); |
4fa5bcfe | 11900 | return -EINVAL; |
d7a18ea7 AN |
11901 | } |
11902 | *tp_name = '\0'; | |
11903 | tp_name++; | |
11904 | ||
4fa5bcfe | 11905 | *link = bpf_program__attach_tracepoint(prog, tp_cat, tp_name); |
d7a18ea7 | 11906 | free(sec_name); |
4fa5bcfe | 11907 | return libbpf_get_error(*link); |
d7a18ea7 AN |
11908 | } |
11909 | ||
942025c9 | 11910 | struct bpf_link *bpf_program__attach_raw_tracepoint(const struct bpf_program *prog, |
84bf5e1f AN |
11911 | const char *tp_name) |
11912 | { | |
11913 | char errmsg[STRERR_BUFSIZE]; | |
c016b68e | 11914 | struct bpf_link *link; |
84bf5e1f AN |
11915 | int prog_fd, pfd; |
11916 | ||
11917 | prog_fd = bpf_program__fd(prog); | |
11918 | if (prog_fd < 0) { | |
52109584 | 11919 | pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
e9fc3ce9 | 11920 | return libbpf_err_ptr(-EINVAL); |
84bf5e1f AN |
11921 | } |
11922 | ||
d6958706 | 11923 | link = calloc(1, sizeof(*link)); |
84bf5e1f | 11924 | if (!link) |
e9fc3ce9 | 11925 | return libbpf_err_ptr(-ENOMEM); |
c016b68e | 11926 | link->detach = &bpf_link__detach_fd; |
84bf5e1f AN |
11927 | |
11928 | pfd = bpf_raw_tracepoint_open(tp_name, prog_fd); | |
11929 | if (pfd < 0) { | |
11930 | pfd = -errno; | |
11931 | free(link); | |
52109584 AN |
11932 | pr_warn("prog '%s': failed to attach to raw tracepoint '%s': %s\n", |
11933 | prog->name, tp_name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); | |
e9fc3ce9 | 11934 | return libbpf_err_ptr(pfd); |
84bf5e1f AN |
11935 | } |
11936 | link->fd = pfd; | |
c016b68e | 11937 | return link; |
84bf5e1f AN |
11938 | } |
11939 | ||
4fa5bcfe | 11940 | static int attach_raw_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link) |
d7a18ea7 | 11941 | { |
ccaf12d6 | 11942 | static const char *const prefixes[] = { |
9af8efc4 AN |
11943 | "raw_tp", |
11944 | "raw_tracepoint", | |
11945 | "raw_tp.w", | |
11946 | "raw_tracepoint.w", | |
ccaf12d6 HT |
11947 | }; |
11948 | size_t i; | |
11949 | const char *tp_name = NULL; | |
13d35a0c | 11950 | |
9af8efc4 AN |
11951 | *link = NULL; |
11952 | ||
ccaf12d6 | 11953 | for (i = 0; i < ARRAY_SIZE(prefixes); i++) { |
9af8efc4 AN |
11954 | size_t pfx_len; |
11955 | ||
11956 | if (!str_has_pfx(prog->sec_name, prefixes[i])) | |
11957 | continue; | |
11958 | ||
11959 | pfx_len = strlen(prefixes[i]); | |
11960 | /* no auto-attach case of, e.g., SEC("raw_tp") */ | |
11961 | if (prog->sec_name[pfx_len] == '\0') | |
11962 | return 0; | |
11963 | ||
11964 | if (prog->sec_name[pfx_len] != '/') | |
11965 | continue; | |
11966 | ||
11967 | tp_name = prog->sec_name + pfx_len + 1; | |
11968 | break; | |
ccaf12d6 | 11969 | } |
9af8efc4 | 11970 | |
ccaf12d6 HT |
11971 | if (!tp_name) { |
11972 | pr_warn("prog '%s': invalid section name '%s'\n", | |
11973 | prog->name, prog->sec_name); | |
4fa5bcfe | 11974 | return -EINVAL; |
ccaf12d6 | 11975 | } |
d7a18ea7 | 11976 | |
4fa5bcfe | 11977 | *link = bpf_program__attach_raw_tracepoint(prog, tp_name); |
5fd2a60a | 11978 | return libbpf_get_error(*link); |
d7a18ea7 AN |
11979 | } |
11980 | ||
1e092a03 | 11981 | /* Common logic for all BPF program types that attach to a btf_id */ |
129b9c5e KFL |
11982 | static struct bpf_link *bpf_program__attach_btf_id(const struct bpf_program *prog, |
11983 | const struct bpf_trace_opts *opts) | |
b8c54ea4 | 11984 | { |
129b9c5e | 11985 | LIBBPF_OPTS(bpf_link_create_opts, link_opts); |
b8c54ea4 | 11986 | char errmsg[STRERR_BUFSIZE]; |
c016b68e | 11987 | struct bpf_link *link; |
b8c54ea4 AS |
11988 | int prog_fd, pfd; |
11989 | ||
129b9c5e KFL |
11990 | if (!OPTS_VALID(opts, bpf_trace_opts)) |
11991 | return libbpf_err_ptr(-EINVAL); | |
11992 | ||
b8c54ea4 AS |
11993 | prog_fd = bpf_program__fd(prog); |
11994 | if (prog_fd < 0) { | |
52109584 | 11995 | pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
e9fc3ce9 | 11996 | return libbpf_err_ptr(-EINVAL); |
b8c54ea4 AS |
11997 | } |
11998 | ||
d6958706 | 11999 | link = calloc(1, sizeof(*link)); |
b8c54ea4 | 12000 | if (!link) |
e9fc3ce9 | 12001 | return libbpf_err_ptr(-ENOMEM); |
c016b68e | 12002 | link->detach = &bpf_link__detach_fd; |
b8c54ea4 | 12003 | |
8462e0b4 | 12004 | /* libbpf is smart enough to redirect to BPF_RAW_TRACEPOINT_OPEN on old kernels */ |
129b9c5e KFL |
12005 | link_opts.tracing.cookie = OPTS_GET(opts, cookie, 0); |
12006 | pfd = bpf_link_create(prog_fd, 0, bpf_program__expected_attach_type(prog), &link_opts); | |
b8c54ea4 AS |
12007 | if (pfd < 0) { |
12008 | pfd = -errno; | |
12009 | free(link); | |
52109584 AN |
12010 | pr_warn("prog '%s': failed to attach: %s\n", |
12011 | prog->name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); | |
e9fc3ce9 | 12012 | return libbpf_err_ptr(pfd); |
b8c54ea4 AS |
12013 | } |
12014 | link->fd = pfd; | |
003fed59 | 12015 | return link; |
b8c54ea4 AS |
12016 | } |
12017 | ||
942025c9 | 12018 | struct bpf_link *bpf_program__attach_trace(const struct bpf_program *prog) |
1e092a03 | 12019 | { |
129b9c5e KFL |
12020 | return bpf_program__attach_btf_id(prog, NULL); |
12021 | } | |
12022 | ||
12023 | struct bpf_link *bpf_program__attach_trace_opts(const struct bpf_program *prog, | |
12024 | const struct bpf_trace_opts *opts) | |
12025 | { | |
12026 | return bpf_program__attach_btf_id(prog, opts); | |
1e092a03 KS |
12027 | } |
12028 | ||
942025c9 | 12029 | struct bpf_link *bpf_program__attach_lsm(const struct bpf_program *prog) |
1e092a03 | 12030 | { |
129b9c5e | 12031 | return bpf_program__attach_btf_id(prog, NULL); |
1e092a03 KS |
12032 | } |
12033 | ||
4fa5bcfe | 12034 | static int attach_trace(const struct bpf_program *prog, long cookie, struct bpf_link **link) |
d7a18ea7 | 12035 | { |
4fa5bcfe AN |
12036 | *link = bpf_program__attach_trace(prog); |
12037 | return libbpf_get_error(*link); | |
d7a18ea7 AN |
12038 | } |
12039 | ||
4fa5bcfe | 12040 | static int attach_lsm(const struct bpf_program *prog, long cookie, struct bpf_link **link) |
1e092a03 | 12041 | { |
4fa5bcfe AN |
12042 | *link = bpf_program__attach_lsm(prog); |
12043 | return libbpf_get_error(*link); | |
1e092a03 KS |
12044 | } |
12045 | ||
d60d81ac | 12046 | static struct bpf_link * |
55cc3768 DB |
12047 | bpf_program_attach_fd(const struct bpf_program *prog, |
12048 | int target_fd, const char *target_name, | |
12049 | const struct bpf_link_create_opts *opts) | |
cc4f864b | 12050 | { |
cc4f864b AN |
12051 | enum bpf_attach_type attach_type; |
12052 | char errmsg[STRERR_BUFSIZE]; | |
12053 | struct bpf_link *link; | |
12054 | int prog_fd, link_fd; | |
12055 | ||
12056 | prog_fd = bpf_program__fd(prog); | |
12057 | if (prog_fd < 0) { | |
52109584 | 12058 | pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
e9fc3ce9 | 12059 | return libbpf_err_ptr(-EINVAL); |
cc4f864b AN |
12060 | } |
12061 | ||
12062 | link = calloc(1, sizeof(*link)); | |
12063 | if (!link) | |
e9fc3ce9 | 12064 | return libbpf_err_ptr(-ENOMEM); |
cc4f864b AN |
12065 | link->detach = &bpf_link__detach_fd; |
12066 | ||
20eccf29 | 12067 | attach_type = bpf_program__expected_attach_type(prog); |
55cc3768 | 12068 | link_fd = bpf_link_create(prog_fd, target_fd, attach_type, opts); |
cc4f864b AN |
12069 | if (link_fd < 0) { |
12070 | link_fd = -errno; | |
12071 | free(link); | |
52109584 AN |
12072 | pr_warn("prog '%s': failed to attach to %s: %s\n", |
12073 | prog->name, target_name, | |
cc4f864b | 12074 | libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg))); |
e9fc3ce9 | 12075 | return libbpf_err_ptr(link_fd); |
cc4f864b AN |
12076 | } |
12077 | link->fd = link_fd; | |
12078 | return link; | |
12079 | } | |
12080 | ||
d60d81ac | 12081 | struct bpf_link * |
942025c9 | 12082 | bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd) |
d60d81ac | 12083 | { |
55cc3768 | 12084 | return bpf_program_attach_fd(prog, cgroup_fd, "cgroup", NULL); |
d60d81ac JS |
12085 | } |
12086 | ||
12087 | struct bpf_link * | |
942025c9 | 12088 | bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd) |
d60d81ac | 12089 | { |
55cc3768 | 12090 | return bpf_program_attach_fd(prog, netns_fd, "netns", NULL); |
d60d81ac JS |
12091 | } |
12092 | ||
942025c9 | 12093 | struct bpf_link *bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex) |
dc8698ca AN |
12094 | { |
12095 | /* target_fd/target_ifindex use the same field in LINK_CREATE */ | |
55cc3768 DB |
12096 | return bpf_program_attach_fd(prog, ifindex, "xdp", NULL); |
12097 | } | |
12098 | ||
12099 | struct bpf_link * | |
12100 | bpf_program__attach_tcx(const struct bpf_program *prog, int ifindex, | |
12101 | const struct bpf_tcx_opts *opts) | |
12102 | { | |
12103 | LIBBPF_OPTS(bpf_link_create_opts, link_create_opts); | |
12104 | __u32 relative_id; | |
12105 | int relative_fd; | |
12106 | ||
12107 | if (!OPTS_VALID(opts, bpf_tcx_opts)) | |
12108 | return libbpf_err_ptr(-EINVAL); | |
12109 | ||
12110 | relative_id = OPTS_GET(opts, relative_id, 0); | |
12111 | relative_fd = OPTS_GET(opts, relative_fd, 0); | |
12112 | ||
12113 | /* validate we don't have unexpected combinations of non-zero fields */ | |
12114 | if (!ifindex) { | |
12115 | pr_warn("prog '%s': target netdevice ifindex cannot be zero\n", | |
12116 | prog->name); | |
12117 | return libbpf_err_ptr(-EINVAL); | |
12118 | } | |
12119 | if (relative_fd && relative_id) { | |
12120 | pr_warn("prog '%s': relative_fd and relative_id cannot be set at the same time\n", | |
12121 | prog->name); | |
12122 | return libbpf_err_ptr(-EINVAL); | |
12123 | } | |
12124 | ||
12125 | link_create_opts.tcx.expected_revision = OPTS_GET(opts, expected_revision, 0); | |
12126 | link_create_opts.tcx.relative_fd = relative_fd; | |
12127 | link_create_opts.tcx.relative_id = relative_id; | |
12128 | link_create_opts.flags = OPTS_GET(opts, flags, 0); | |
12129 | ||
12130 | /* target_fd/target_ifindex use the same field in LINK_CREATE */ | |
12131 | return bpf_program_attach_fd(prog, ifindex, "tcx", &link_create_opts); | |
a5359091 THJ |
12132 | } |
12133 | ||
05c31b4a DB |
12134 | struct bpf_link * |
12135 | bpf_program__attach_netkit(const struct bpf_program *prog, int ifindex, | |
12136 | const struct bpf_netkit_opts *opts) | |
12137 | { | |
12138 | LIBBPF_OPTS(bpf_link_create_opts, link_create_opts); | |
12139 | __u32 relative_id; | |
12140 | int relative_fd; | |
12141 | ||
12142 | if (!OPTS_VALID(opts, bpf_netkit_opts)) | |
12143 | return libbpf_err_ptr(-EINVAL); | |
12144 | ||
12145 | relative_id = OPTS_GET(opts, relative_id, 0); | |
12146 | relative_fd = OPTS_GET(opts, relative_fd, 0); | |
12147 | ||
12148 | /* validate we don't have unexpected combinations of non-zero fields */ | |
12149 | if (!ifindex) { | |
12150 | pr_warn("prog '%s': target netdevice ifindex cannot be zero\n", | |
12151 | prog->name); | |
12152 | return libbpf_err_ptr(-EINVAL); | |
12153 | } | |
12154 | if (relative_fd && relative_id) { | |
12155 | pr_warn("prog '%s': relative_fd and relative_id cannot be set at the same time\n", | |
12156 | prog->name); | |
12157 | return libbpf_err_ptr(-EINVAL); | |
12158 | } | |
12159 | ||
12160 | link_create_opts.netkit.expected_revision = OPTS_GET(opts, expected_revision, 0); | |
12161 | link_create_opts.netkit.relative_fd = relative_fd; | |
12162 | link_create_opts.netkit.relative_id = relative_id; | |
12163 | link_create_opts.flags = OPTS_GET(opts, flags, 0); | |
12164 | ||
12165 | return bpf_program_attach_fd(prog, ifindex, "netkit", &link_create_opts); | |
12166 | } | |
12167 | ||
942025c9 | 12168 | struct bpf_link *bpf_program__attach_freplace(const struct bpf_program *prog, |
a5359091 THJ |
12169 | int target_fd, |
12170 | const char *attach_func_name) | |
12171 | { | |
12172 | int btf_id; | |
12173 | ||
12174 | if (!!target_fd != !!attach_func_name) { | |
12175 | pr_warn("prog '%s': supply none or both of target_fd and attach_func_name\n", | |
12176 | prog->name); | |
e9fc3ce9 | 12177 | return libbpf_err_ptr(-EINVAL); |
a5359091 THJ |
12178 | } |
12179 | ||
12180 | if (prog->type != BPF_PROG_TYPE_EXT) { | |
12181 | pr_warn("prog '%s': only BPF_PROG_TYPE_EXT can attach as freplace", | |
12182 | prog->name); | |
e9fc3ce9 | 12183 | return libbpf_err_ptr(-EINVAL); |
a5359091 THJ |
12184 | } |
12185 | ||
12186 | if (target_fd) { | |
55cc3768 DB |
12187 | LIBBPF_OPTS(bpf_link_create_opts, target_opts); |
12188 | ||
a5359091 THJ |
12189 | btf_id = libbpf_find_prog_btf_id(attach_func_name, target_fd); |
12190 | if (btf_id < 0) | |
e9fc3ce9 | 12191 | return libbpf_err_ptr(btf_id); |
a5359091 | 12192 | |
55cc3768 DB |
12193 | target_opts.target_btf_id = btf_id; |
12194 | ||
12195 | return bpf_program_attach_fd(prog, target_fd, "freplace", | |
12196 | &target_opts); | |
a5359091 THJ |
12197 | } else { |
12198 | /* no target, so use raw_tracepoint_open for compatibility | |
12199 | * with old kernels | |
12200 | */ | |
12201 | return bpf_program__attach_trace(prog); | |
12202 | } | |
dc8698ca AN |
12203 | } |
12204 | ||
c09add2f | 12205 | struct bpf_link * |
942025c9 | 12206 | bpf_program__attach_iter(const struct bpf_program *prog, |
c09add2f YS |
12207 | const struct bpf_iter_attach_opts *opts) |
12208 | { | |
cd31039a | 12209 | DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_create_opts); |
c09add2f YS |
12210 | char errmsg[STRERR_BUFSIZE]; |
12211 | struct bpf_link *link; | |
12212 | int prog_fd, link_fd; | |
cd31039a | 12213 | __u32 target_fd = 0; |
c09add2f YS |
12214 | |
12215 | if (!OPTS_VALID(opts, bpf_iter_attach_opts)) | |
e9fc3ce9 | 12216 | return libbpf_err_ptr(-EINVAL); |
c09add2f | 12217 | |
74fc097d YS |
12218 | link_create_opts.iter_info = OPTS_GET(opts, link_info, (void *)0); |
12219 | link_create_opts.iter_info_len = OPTS_GET(opts, link_info_len, 0); | |
cd31039a | 12220 | |
c09add2f YS |
12221 | prog_fd = bpf_program__fd(prog); |
12222 | if (prog_fd < 0) { | |
52109584 | 12223 | pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
e9fc3ce9 | 12224 | return libbpf_err_ptr(-EINVAL); |
c09add2f YS |
12225 | } |
12226 | ||
12227 | link = calloc(1, sizeof(*link)); | |
12228 | if (!link) | |
e9fc3ce9 | 12229 | return libbpf_err_ptr(-ENOMEM); |
c09add2f YS |
12230 | link->detach = &bpf_link__detach_fd; |
12231 | ||
cd31039a YS |
12232 | link_fd = bpf_link_create(prog_fd, target_fd, BPF_TRACE_ITER, |
12233 | &link_create_opts); | |
c09add2f YS |
12234 | if (link_fd < 0) { |
12235 | link_fd = -errno; | |
12236 | free(link); | |
52109584 AN |
12237 | pr_warn("prog '%s': failed to attach to iterator: %s\n", |
12238 | prog->name, libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg))); | |
e9fc3ce9 | 12239 | return libbpf_err_ptr(link_fd); |
c09add2f YS |
12240 | } |
12241 | link->fd = link_fd; | |
12242 | return link; | |
12243 | } | |
12244 | ||
4fa5bcfe | 12245 | static int attach_iter(const struct bpf_program *prog, long cookie, struct bpf_link **link) |
e9fc3ce9 | 12246 | { |
4fa5bcfe AN |
12247 | *link = bpf_program__attach_iter(prog, NULL); |
12248 | return libbpf_get_error(*link); | |
e9fc3ce9 AN |
12249 | } |
12250 | ||
52364abb FW |
12251 | struct bpf_link *bpf_program__attach_netfilter(const struct bpf_program *prog, |
12252 | const struct bpf_netfilter_opts *opts) | |
12253 | { | |
12254 | LIBBPF_OPTS(bpf_link_create_opts, lopts); | |
12255 | struct bpf_link *link; | |
12256 | int prog_fd, link_fd; | |
12257 | ||
12258 | if (!OPTS_VALID(opts, bpf_netfilter_opts)) | |
12259 | return libbpf_err_ptr(-EINVAL); | |
12260 | ||
12261 | prog_fd = bpf_program__fd(prog); | |
12262 | if (prog_fd < 0) { | |
12263 | pr_warn("prog '%s': can't attach before loaded\n", prog->name); | |
12264 | return libbpf_err_ptr(-EINVAL); | |
12265 | } | |
12266 | ||
12267 | link = calloc(1, sizeof(*link)); | |
12268 | if (!link) | |
12269 | return libbpf_err_ptr(-ENOMEM); | |
12270 | ||
12271 | link->detach = &bpf_link__detach_fd; | |
12272 | ||
12273 | lopts.netfilter.pf = OPTS_GET(opts, pf, 0); | |
12274 | lopts.netfilter.hooknum = OPTS_GET(opts, hooknum, 0); | |
12275 | lopts.netfilter.priority = OPTS_GET(opts, priority, 0); | |
12276 | lopts.netfilter.flags = OPTS_GET(opts, flags, 0); | |
12277 | ||
12278 | link_fd = bpf_link_create(prog_fd, 0, BPF_NETFILTER, &lopts); | |
12279 | if (link_fd < 0) { | |
12280 | char errmsg[STRERR_BUFSIZE]; | |
12281 | ||
12282 | link_fd = -errno; | |
12283 | free(link); | |
12284 | pr_warn("prog '%s': failed to attach to netfilter: %s\n", | |
12285 | prog->name, libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg))); | |
12286 | return libbpf_err_ptr(link_fd); | |
12287 | } | |
12288 | link->fd = link_fd; | |
12289 | ||
12290 | return link; | |
12291 | } | |
12292 | ||
942025c9 | 12293 | struct bpf_link *bpf_program__attach(const struct bpf_program *prog) |
d7a18ea7 | 12294 | { |
4fa5bcfe AN |
12295 | struct bpf_link *link = NULL; |
12296 | int err; | |
12297 | ||
12298 | if (!prog->sec_def || !prog->sec_def->prog_attach_fn) | |
12299 | return libbpf_err_ptr(-EOPNOTSUPP); | |
d7a18ea7 | 12300 | |
4fa5bcfe AN |
12301 | err = prog->sec_def->prog_attach_fn(prog, prog->sec_def->cookie, &link); |
12302 | if (err) | |
12303 | return libbpf_err_ptr(err); | |
12304 | ||
12305 | /* When calling bpf_program__attach() explicitly, auto-attach support | |
12306 | * is expected to work, so NULL returned link is considered an error. | |
12307 | * This is different for skeleton's attach, see comment in | |
12308 | * bpf_object__attach_skeleton(). | |
12309 | */ | |
12310 | if (!link) | |
12311 | return libbpf_err_ptr(-EOPNOTSUPP); | |
12312 | ||
12313 | return link; | |
d7a18ea7 AN |
12314 | } |
12315 | ||
8d1608d7 KFL |
12316 | struct bpf_link_struct_ops { |
12317 | struct bpf_link link; | |
12318 | int map_fd; | |
12319 | }; | |
12320 | ||
590a0088 MKL |
12321 | static int bpf_link__detach_struct_ops(struct bpf_link *link) |
12322 | { | |
8d1608d7 | 12323 | struct bpf_link_struct_ops *st_link; |
590a0088 MKL |
12324 | __u32 zero = 0; |
12325 | ||
8d1608d7 | 12326 | st_link = container_of(link, struct bpf_link_struct_ops, link); |
590a0088 | 12327 | |
8d1608d7 KFL |
12328 | if (st_link->map_fd < 0) |
12329 | /* w/o a real link */ | |
12330 | return bpf_map_delete_elem(link->fd, &zero); | |
12331 | ||
12332 | return close(link->fd); | |
590a0088 MKL |
12333 | } |
12334 | ||
942025c9 | 12335 | struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map) |
590a0088 | 12336 | { |
8d1608d7 KFL |
12337 | struct bpf_link_struct_ops *link; |
12338 | __u32 zero = 0; | |
12339 | int err, fd; | |
590a0088 MKL |
12340 | |
12341 | if (!bpf_map__is_struct_ops(map) || map->fd == -1) | |
e9fc3ce9 | 12342 | return libbpf_err_ptr(-EINVAL); |
590a0088 MKL |
12343 | |
12344 | link = calloc(1, sizeof(*link)); | |
12345 | if (!link) | |
e9fc3ce9 | 12346 | return libbpf_err_ptr(-EINVAL); |
590a0088 | 12347 | |
8d1608d7 KFL |
12348 | /* kern_vdata should be prepared during the loading phase. */ |
12349 | err = bpf_map_update_elem(map->fd, &zero, map->st_ops->kern_vdata, 0); | |
12350 | /* It can be EBUSY if the map has been used to create or | |
12351 | * update a link before. We don't allow updating the value of | |
12352 | * a struct_ops once it is set. That ensures that the value | |
12353 | * never changed. So, it is safe to skip EBUSY. | |
12354 | */ | |
12355 | if (err && (!(map->def.map_flags & BPF_F_LINK) || err != -EBUSY)) { | |
12356 | free(link); | |
12357 | return libbpf_err_ptr(err); | |
12358 | } | |
590a0088 | 12359 | |
8d1608d7 | 12360 | link->link.detach = bpf_link__detach_struct_ops; |
590a0088 | 12361 | |
8d1608d7 KFL |
12362 | if (!(map->def.map_flags & BPF_F_LINK)) { |
12363 | /* w/o a real link */ | |
12364 | link->link.fd = map->fd; | |
12365 | link->map_fd = -1; | |
12366 | return &link->link; | |
590a0088 MKL |
12367 | } |
12368 | ||
8d1608d7 KFL |
12369 | fd = bpf_link_create(map->fd, 0, BPF_STRUCT_OPS, NULL); |
12370 | if (fd < 0) { | |
590a0088 | 12371 | free(link); |
8d1608d7 | 12372 | return libbpf_err_ptr(fd); |
590a0088 MKL |
12373 | } |
12374 | ||
8d1608d7 KFL |
12375 | link->link.fd = fd; |
12376 | link->map_fd = map->fd; | |
590a0088 | 12377 | |
8d1608d7 | 12378 | return &link->link; |
590a0088 MKL |
12379 | } |
12380 | ||
912dd4b0 KFL |
12381 | /* |
12382 | * Swap the back struct_ops of a link with a new struct_ops map. | |
12383 | */ | |
12384 | int bpf_link__update_map(struct bpf_link *link, const struct bpf_map *map) | |
12385 | { | |
12386 | struct bpf_link_struct_ops *st_ops_link; | |
12387 | __u32 zero = 0; | |
12388 | int err; | |
12389 | ||
12390 | if (!bpf_map__is_struct_ops(map) || map->fd < 0) | |
12391 | return -EINVAL; | |
12392 | ||
12393 | st_ops_link = container_of(link, struct bpf_link_struct_ops, link); | |
12394 | /* Ensure the type of a link is correct */ | |
12395 | if (st_ops_link->map_fd < 0) | |
12396 | return -EINVAL; | |
12397 | ||
12398 | err = bpf_map_update_elem(map->fd, &zero, map->st_ops->kern_vdata, 0); | |
12399 | /* It can be EBUSY if the map has been used to create or | |
12400 | * update a link before. We don't allow updating the value of | |
12401 | * a struct_ops once it is set. That ensures that the value | |
12402 | * never changed. So, it is safe to skip EBUSY. | |
12403 | */ | |
12404 | if (err && err != -EBUSY) | |
12405 | return err; | |
12406 | ||
12407 | err = bpf_link_update(link->fd, map->fd, NULL); | |
12408 | if (err < 0) | |
12409 | return err; | |
12410 | ||
12411 | st_ops_link->map_fd = map->fd; | |
12412 | ||
12413 | return 0; | |
12414 | } | |
12415 | ||
22dd7a58 AN |
12416 | typedef enum bpf_perf_event_ret (*bpf_perf_event_print_t)(struct perf_event_header *hdr, |
12417 | void *private_data); | |
12418 | ||
7218c28c CL |
12419 | static enum bpf_perf_event_ret |
12420 | perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size, | |
12421 | void **copy_mem, size_t *copy_size, | |
12422 | bpf_perf_event_print_t fn, void *private_data) | |
d0cabbb0 | 12423 | { |
3dca2115 | 12424 | struct perf_event_mmap_page *header = mmap_mem; |
a64af0ef | 12425 | __u64 data_head = ring_buffer_read_head(header); |
d0cabbb0 | 12426 | __u64 data_tail = header->data_tail; |
3dca2115 DB |
12427 | void *base = ((__u8 *)header) + page_size; |
12428 | int ret = LIBBPF_PERF_EVENT_CONT; | |
12429 | struct perf_event_header *ehdr; | |
12430 | size_t ehdr_size; | |
12431 | ||
12432 | while (data_head != data_tail) { | |
12433 | ehdr = base + (data_tail & (mmap_size - 1)); | |
12434 | ehdr_size = ehdr->size; | |
12435 | ||
12436 | if (((void *)ehdr) + ehdr_size > base + mmap_size) { | |
12437 | void *copy_start = ehdr; | |
12438 | size_t len_first = base + mmap_size - copy_start; | |
12439 | size_t len_secnd = ehdr_size - len_first; | |
12440 | ||
12441 | if (*copy_size < ehdr_size) { | |
12442 | free(*copy_mem); | |
12443 | *copy_mem = malloc(ehdr_size); | |
12444 | if (!*copy_mem) { | |
12445 | *copy_size = 0; | |
d0cabbb0 JK |
12446 | ret = LIBBPF_PERF_EVENT_ERROR; |
12447 | break; | |
12448 | } | |
3dca2115 | 12449 | *copy_size = ehdr_size; |
d0cabbb0 JK |
12450 | } |
12451 | ||
3dca2115 DB |
12452 | memcpy(*copy_mem, copy_start, len_first); |
12453 | memcpy(*copy_mem + len_first, base, len_secnd); | |
12454 | ehdr = *copy_mem; | |
d0cabbb0 JK |
12455 | } |
12456 | ||
3dca2115 DB |
12457 | ret = fn(ehdr, private_data); |
12458 | data_tail += ehdr_size; | |
d0cabbb0 JK |
12459 | if (ret != LIBBPF_PERF_EVENT_CONT) |
12460 | break; | |
d0cabbb0 JK |
12461 | } |
12462 | ||
a64af0ef | 12463 | ring_buffer_write_tail(header, data_tail); |
e9fc3ce9 | 12464 | return libbpf_err(ret); |
d0cabbb0 | 12465 | } |
34be1646 | 12466 | |
fb84b822 AN |
12467 | struct perf_buffer; |
12468 | ||
12469 | struct perf_buffer_params { | |
12470 | struct perf_event_attr *attr; | |
12471 | /* if event_cb is specified, it takes precendence */ | |
12472 | perf_buffer_event_fn event_cb; | |
12473 | /* sample_cb and lost_cb are higher-level common-case callbacks */ | |
12474 | perf_buffer_sample_fn sample_cb; | |
12475 | perf_buffer_lost_fn lost_cb; | |
12476 | void *ctx; | |
12477 | int cpu_cnt; | |
12478 | int *cpus; | |
12479 | int *map_keys; | |
12480 | }; | |
12481 | ||
12482 | struct perf_cpu_buf { | |
12483 | struct perf_buffer *pb; | |
12484 | void *base; /* mmap()'ed memory */ | |
12485 | void *buf; /* for reconstructing segmented data */ | |
12486 | size_t buf_size; | |
12487 | int fd; | |
12488 | int cpu; | |
12489 | int map_key; | |
12490 | }; | |
12491 | ||
12492 | struct perf_buffer { | |
12493 | perf_buffer_event_fn event_cb; | |
12494 | perf_buffer_sample_fn sample_cb; | |
12495 | perf_buffer_lost_fn lost_cb; | |
12496 | void *ctx; /* passed into callbacks */ | |
12497 | ||
12498 | size_t page_size; | |
12499 | size_t mmap_size; | |
12500 | struct perf_cpu_buf **cpu_bufs; | |
12501 | struct epoll_event *events; | |
783b8f01 | 12502 | int cpu_cnt; /* number of allocated CPU buffers */ |
fb84b822 AN |
12503 | int epoll_fd; /* perf event FD */ |
12504 | int map_fd; /* BPF_MAP_TYPE_PERF_EVENT_ARRAY BPF map FD */ | |
12505 | }; | |
12506 | ||
12507 | static void perf_buffer__free_cpu_buf(struct perf_buffer *pb, | |
12508 | struct perf_cpu_buf *cpu_buf) | |
12509 | { | |
12510 | if (!cpu_buf) | |
12511 | return; | |
12512 | if (cpu_buf->base && | |
12513 | munmap(cpu_buf->base, pb->mmap_size + pb->page_size)) | |
be18010e | 12514 | pr_warn("failed to munmap cpu_buf #%d\n", cpu_buf->cpu); |
fb84b822 AN |
12515 | if (cpu_buf->fd >= 0) { |
12516 | ioctl(cpu_buf->fd, PERF_EVENT_IOC_DISABLE, 0); | |
12517 | close(cpu_buf->fd); | |
12518 | } | |
12519 | free(cpu_buf->buf); | |
12520 | free(cpu_buf); | |
12521 | } | |
12522 | ||
12523 | void perf_buffer__free(struct perf_buffer *pb) | |
12524 | { | |
12525 | int i; | |
12526 | ||
50450fc7 | 12527 | if (IS_ERR_OR_NULL(pb)) |
fb84b822 AN |
12528 | return; |
12529 | if (pb->cpu_bufs) { | |
601b05ca | 12530 | for (i = 0; i < pb->cpu_cnt; i++) { |
fb84b822 AN |
12531 | struct perf_cpu_buf *cpu_buf = pb->cpu_bufs[i]; |
12532 | ||
601b05ca EC |
12533 | if (!cpu_buf) |
12534 | continue; | |
12535 | ||
fb84b822 AN |
12536 | bpf_map_delete_elem(pb->map_fd, &cpu_buf->map_key); |
12537 | perf_buffer__free_cpu_buf(pb, cpu_buf); | |
12538 | } | |
12539 | free(pb->cpu_bufs); | |
12540 | } | |
12541 | if (pb->epoll_fd >= 0) | |
12542 | close(pb->epoll_fd); | |
12543 | free(pb->events); | |
12544 | free(pb); | |
12545 | } | |
12546 | ||
12547 | static struct perf_cpu_buf * | |
12548 | perf_buffer__open_cpu_buf(struct perf_buffer *pb, struct perf_event_attr *attr, | |
12549 | int cpu, int map_key) | |
12550 | { | |
12551 | struct perf_cpu_buf *cpu_buf; | |
12552 | char msg[STRERR_BUFSIZE]; | |
12553 | int err; | |
12554 | ||
12555 | cpu_buf = calloc(1, sizeof(*cpu_buf)); | |
12556 | if (!cpu_buf) | |
12557 | return ERR_PTR(-ENOMEM); | |
12558 | ||
12559 | cpu_buf->pb = pb; | |
12560 | cpu_buf->cpu = cpu; | |
12561 | cpu_buf->map_key = map_key; | |
12562 | ||
12563 | cpu_buf->fd = syscall(__NR_perf_event_open, attr, -1 /* pid */, cpu, | |
12564 | -1, PERF_FLAG_FD_CLOEXEC); | |
12565 | if (cpu_buf->fd < 0) { | |
12566 | err = -errno; | |
be18010e KW |
12567 | pr_warn("failed to open perf buffer event on cpu #%d: %s\n", |
12568 | cpu, libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
12569 | goto error; |
12570 | } | |
12571 | ||
12572 | cpu_buf->base = mmap(NULL, pb->mmap_size + pb->page_size, | |
12573 | PROT_READ | PROT_WRITE, MAP_SHARED, | |
12574 | cpu_buf->fd, 0); | |
12575 | if (cpu_buf->base == MAP_FAILED) { | |
12576 | cpu_buf->base = NULL; | |
12577 | err = -errno; | |
be18010e KW |
12578 | pr_warn("failed to mmap perf buffer on cpu #%d: %s\n", |
12579 | cpu, libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
12580 | goto error; |
12581 | } | |
12582 | ||
12583 | if (ioctl(cpu_buf->fd, PERF_EVENT_IOC_ENABLE, 0) < 0) { | |
12584 | err = -errno; | |
be18010e KW |
12585 | pr_warn("failed to enable perf buffer event on cpu #%d: %s\n", |
12586 | cpu, libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
12587 | goto error; |
12588 | } | |
12589 | ||
12590 | return cpu_buf; | |
12591 | ||
12592 | error: | |
12593 | perf_buffer__free_cpu_buf(pb, cpu_buf); | |
12594 | return (struct perf_cpu_buf *)ERR_PTR(err); | |
12595 | } | |
12596 | ||
12597 | static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, | |
12598 | struct perf_buffer_params *p); | |
12599 | ||
22dd7a58 AN |
12600 | struct perf_buffer *perf_buffer__new(int map_fd, size_t page_cnt, |
12601 | perf_buffer_sample_fn sample_cb, | |
12602 | perf_buffer_lost_fn lost_cb, | |
12603 | void *ctx, | |
12604 | const struct perf_buffer_opts *opts) | |
fb84b822 | 12605 | { |
813847a3 | 12606 | const size_t attr_sz = sizeof(struct perf_event_attr); |
fb84b822 | 12607 | struct perf_buffer_params p = {}; |
813847a3 | 12608 | struct perf_event_attr attr; |
ab8684b8 | 12609 | __u32 sample_period; |
41788934 AN |
12610 | |
12611 | if (!OPTS_VALID(opts, perf_buffer_opts)) | |
12612 | return libbpf_err_ptr(-EINVAL); | |
4be6e05c | 12613 | |
ab8684b8 JD |
12614 | sample_period = OPTS_GET(opts, sample_period, 1); |
12615 | if (!sample_period) | |
12616 | sample_period = 1; | |
12617 | ||
813847a3 AN |
12618 | memset(&attr, 0, attr_sz); |
12619 | attr.size = attr_sz; | |
65bb2e0f | 12620 | attr.config = PERF_COUNT_SW_BPF_OUTPUT; |
4be6e05c ACM |
12621 | attr.type = PERF_TYPE_SOFTWARE; |
12622 | attr.sample_type = PERF_SAMPLE_RAW; | |
ab8684b8 JD |
12623 | attr.sample_period = sample_period; |
12624 | attr.wakeup_events = sample_period; | |
fb84b822 AN |
12625 | |
12626 | p.attr = &attr; | |
41788934 AN |
12627 | p.sample_cb = sample_cb; |
12628 | p.lost_cb = lost_cb; | |
12629 | p.ctx = ctx; | |
fb84b822 | 12630 | |
e9fc3ce9 | 12631 | return libbpf_ptr(__perf_buffer__new(map_fd, page_cnt, &p)); |
fb84b822 AN |
12632 | } |
12633 | ||
22dd7a58 AN |
12634 | struct perf_buffer *perf_buffer__new_raw(int map_fd, size_t page_cnt, |
12635 | struct perf_event_attr *attr, | |
12636 | perf_buffer_event_fn event_cb, void *ctx, | |
12637 | const struct perf_buffer_raw_opts *opts) | |
fb84b822 AN |
12638 | { |
12639 | struct perf_buffer_params p = {}; | |
12640 | ||
41332d6e | 12641 | if (!attr) |
41788934 AN |
12642 | return libbpf_err_ptr(-EINVAL); |
12643 | ||
12644 | if (!OPTS_VALID(opts, perf_buffer_raw_opts)) | |
12645 | return libbpf_err_ptr(-EINVAL); | |
12646 | ||
12647 | p.attr = attr; | |
12648 | p.event_cb = event_cb; | |
12649 | p.ctx = ctx; | |
12650 | p.cpu_cnt = OPTS_GET(opts, cpu_cnt, 0); | |
12651 | p.cpus = OPTS_GET(opts, cpus, NULL); | |
12652 | p.map_keys = OPTS_GET(opts, map_keys, NULL); | |
fb84b822 | 12653 | |
e9fc3ce9 | 12654 | return libbpf_ptr(__perf_buffer__new(map_fd, page_cnt, &p)); |
fb84b822 AN |
12655 | } |
12656 | ||
12657 | static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, | |
12658 | struct perf_buffer_params *p) | |
12659 | { | |
783b8f01 | 12660 | const char *online_cpus_file = "/sys/devices/system/cpu/online"; |
0e289487 | 12661 | struct bpf_map_info map; |
fb84b822 AN |
12662 | char msg[STRERR_BUFSIZE]; |
12663 | struct perf_buffer *pb; | |
783b8f01 | 12664 | bool *online = NULL; |
fb84b822 | 12665 | __u32 map_info_len; |
783b8f01 | 12666 | int err, i, j, n; |
fb84b822 | 12667 | |
41332d6e | 12668 | if (page_cnt == 0 || (page_cnt & (page_cnt - 1))) { |
be18010e KW |
12669 | pr_warn("page count should be power of two, but is %zu\n", |
12670 | page_cnt); | |
fb84b822 AN |
12671 | return ERR_PTR(-EINVAL); |
12672 | } | |
12673 | ||
0e289487 AN |
12674 | /* best-effort sanity checks */ |
12675 | memset(&map, 0, sizeof(map)); | |
fb84b822 | 12676 | map_info_len = sizeof(map); |
629dfc66 | 12677 | err = bpf_map_get_info_by_fd(map_fd, &map, &map_info_len); |
fb84b822 AN |
12678 | if (err) { |
12679 | err = -errno; | |
0e289487 AN |
12680 | /* if BPF_OBJ_GET_INFO_BY_FD is supported, will return |
12681 | * -EBADFD, -EFAULT, or -E2BIG on real error | |
12682 | */ | |
12683 | if (err != -EINVAL) { | |
12684 | pr_warn("failed to get map info for map FD %d: %s\n", | |
12685 | map_fd, libbpf_strerror_r(err, msg, sizeof(msg))); | |
12686 | return ERR_PTR(err); | |
12687 | } | |
12688 | pr_debug("failed to get map info for FD %d; API not supported? Ignoring...\n", | |
12689 | map_fd); | |
12690 | } else { | |
12691 | if (map.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) { | |
12692 | pr_warn("map '%s' should be BPF_MAP_TYPE_PERF_EVENT_ARRAY\n", | |
12693 | map.name); | |
12694 | return ERR_PTR(-EINVAL); | |
12695 | } | |
fb84b822 AN |
12696 | } |
12697 | ||
12698 | pb = calloc(1, sizeof(*pb)); | |
12699 | if (!pb) | |
12700 | return ERR_PTR(-ENOMEM); | |
12701 | ||
12702 | pb->event_cb = p->event_cb; | |
12703 | pb->sample_cb = p->sample_cb; | |
12704 | pb->lost_cb = p->lost_cb; | |
12705 | pb->ctx = p->ctx; | |
12706 | ||
12707 | pb->page_size = getpagesize(); | |
12708 | pb->mmap_size = pb->page_size * page_cnt; | |
12709 | pb->map_fd = map_fd; | |
12710 | ||
12711 | pb->epoll_fd = epoll_create1(EPOLL_CLOEXEC); | |
12712 | if (pb->epoll_fd < 0) { | |
12713 | err = -errno; | |
be18010e KW |
12714 | pr_warn("failed to create epoll instance: %s\n", |
12715 | libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
12716 | goto error; |
12717 | } | |
12718 | ||
12719 | if (p->cpu_cnt > 0) { | |
12720 | pb->cpu_cnt = p->cpu_cnt; | |
12721 | } else { | |
12722 | pb->cpu_cnt = libbpf_num_possible_cpus(); | |
12723 | if (pb->cpu_cnt < 0) { | |
12724 | err = pb->cpu_cnt; | |
12725 | goto error; | |
12726 | } | |
0e289487 | 12727 | if (map.max_entries && map.max_entries < pb->cpu_cnt) |
fb84b822 AN |
12728 | pb->cpu_cnt = map.max_entries; |
12729 | } | |
12730 | ||
12731 | pb->events = calloc(pb->cpu_cnt, sizeof(*pb->events)); | |
12732 | if (!pb->events) { | |
12733 | err = -ENOMEM; | |
be18010e | 12734 | pr_warn("failed to allocate events: out of memory\n"); |
fb84b822 AN |
12735 | goto error; |
12736 | } | |
12737 | pb->cpu_bufs = calloc(pb->cpu_cnt, sizeof(*pb->cpu_bufs)); | |
12738 | if (!pb->cpu_bufs) { | |
12739 | err = -ENOMEM; | |
be18010e | 12740 | pr_warn("failed to allocate buffers: out of memory\n"); |
fb84b822 AN |
12741 | goto error; |
12742 | } | |
12743 | ||
783b8f01 AN |
12744 | err = parse_cpu_mask_file(online_cpus_file, &online, &n); |
12745 | if (err) { | |
12746 | pr_warn("failed to get online CPU mask: %d\n", err); | |
12747 | goto error; | |
12748 | } | |
12749 | ||
12750 | for (i = 0, j = 0; i < pb->cpu_cnt; i++) { | |
fb84b822 AN |
12751 | struct perf_cpu_buf *cpu_buf; |
12752 | int cpu, map_key; | |
12753 | ||
12754 | cpu = p->cpu_cnt > 0 ? p->cpus[i] : i; | |
12755 | map_key = p->cpu_cnt > 0 ? p->map_keys[i] : i; | |
12756 | ||
783b8f01 AN |
12757 | /* in case user didn't explicitly requested particular CPUs to |
12758 | * be attached to, skip offline/not present CPUs | |
12759 | */ | |
12760 | if (p->cpu_cnt <= 0 && (cpu >= n || !online[cpu])) | |
12761 | continue; | |
12762 | ||
fb84b822 AN |
12763 | cpu_buf = perf_buffer__open_cpu_buf(pb, p->attr, cpu, map_key); |
12764 | if (IS_ERR(cpu_buf)) { | |
12765 | err = PTR_ERR(cpu_buf); | |
12766 | goto error; | |
12767 | } | |
12768 | ||
783b8f01 | 12769 | pb->cpu_bufs[j] = cpu_buf; |
fb84b822 AN |
12770 | |
12771 | err = bpf_map_update_elem(pb->map_fd, &map_key, | |
12772 | &cpu_buf->fd, 0); | |
12773 | if (err) { | |
12774 | err = -errno; | |
be18010e KW |
12775 | pr_warn("failed to set cpu #%d, key %d -> perf FD %d: %s\n", |
12776 | cpu, map_key, cpu_buf->fd, | |
12777 | libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
12778 | goto error; |
12779 | } | |
12780 | ||
783b8f01 AN |
12781 | pb->events[j].events = EPOLLIN; |
12782 | pb->events[j].data.ptr = cpu_buf; | |
fb84b822 | 12783 | if (epoll_ctl(pb->epoll_fd, EPOLL_CTL_ADD, cpu_buf->fd, |
783b8f01 | 12784 | &pb->events[j]) < 0) { |
fb84b822 | 12785 | err = -errno; |
be18010e KW |
12786 | pr_warn("failed to epoll_ctl cpu #%d perf FD %d: %s\n", |
12787 | cpu, cpu_buf->fd, | |
12788 | libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
12789 | goto error; |
12790 | } | |
783b8f01 | 12791 | j++; |
fb84b822 | 12792 | } |
783b8f01 AN |
12793 | pb->cpu_cnt = j; |
12794 | free(online); | |
fb84b822 AN |
12795 | |
12796 | return pb; | |
12797 | ||
12798 | error: | |
783b8f01 | 12799 | free(online); |
fb84b822 AN |
12800 | if (pb) |
12801 | perf_buffer__free(pb); | |
12802 | return ERR_PTR(err); | |
12803 | } | |
12804 | ||
12805 | struct perf_sample_raw { | |
12806 | struct perf_event_header header; | |
12807 | uint32_t size; | |
385bbf7b | 12808 | char data[]; |
fb84b822 AN |
12809 | }; |
12810 | ||
12811 | struct perf_sample_lost { | |
12812 | struct perf_event_header header; | |
12813 | uint64_t id; | |
12814 | uint64_t lost; | |
12815 | uint64_t sample_id; | |
12816 | }; | |
12817 | ||
12818 | static enum bpf_perf_event_ret | |
12819 | perf_buffer__process_record(struct perf_event_header *e, void *ctx) | |
12820 | { | |
12821 | struct perf_cpu_buf *cpu_buf = ctx; | |
12822 | struct perf_buffer *pb = cpu_buf->pb; | |
12823 | void *data = e; | |
12824 | ||
12825 | /* user wants full control over parsing perf event */ | |
12826 | if (pb->event_cb) | |
12827 | return pb->event_cb(pb->ctx, cpu_buf->cpu, e); | |
12828 | ||
12829 | switch (e->type) { | |
12830 | case PERF_RECORD_SAMPLE: { | |
12831 | struct perf_sample_raw *s = data; | |
12832 | ||
12833 | if (pb->sample_cb) | |
12834 | pb->sample_cb(pb->ctx, cpu_buf->cpu, s->data, s->size); | |
12835 | break; | |
12836 | } | |
12837 | case PERF_RECORD_LOST: { | |
12838 | struct perf_sample_lost *s = data; | |
12839 | ||
12840 | if (pb->lost_cb) | |
12841 | pb->lost_cb(pb->ctx, cpu_buf->cpu, s->lost); | |
12842 | break; | |
12843 | } | |
12844 | default: | |
be18010e | 12845 | pr_warn("unknown perf sample type %d\n", e->type); |
fb84b822 AN |
12846 | return LIBBPF_PERF_EVENT_ERROR; |
12847 | } | |
12848 | return LIBBPF_PERF_EVENT_CONT; | |
12849 | } | |
12850 | ||
12851 | static int perf_buffer__process_records(struct perf_buffer *pb, | |
12852 | struct perf_cpu_buf *cpu_buf) | |
12853 | { | |
12854 | enum bpf_perf_event_ret ret; | |
12855 | ||
7218c28c CL |
12856 | ret = perf_event_read_simple(cpu_buf->base, pb->mmap_size, |
12857 | pb->page_size, &cpu_buf->buf, | |
12858 | &cpu_buf->buf_size, | |
12859 | perf_buffer__process_record, cpu_buf); | |
fb84b822 AN |
12860 | if (ret != LIBBPF_PERF_EVENT_CONT) |
12861 | return ret; | |
12862 | return 0; | |
12863 | } | |
12864 | ||
dca5612f AN |
12865 | int perf_buffer__epoll_fd(const struct perf_buffer *pb) |
12866 | { | |
12867 | return pb->epoll_fd; | |
12868 | } | |
12869 | ||
fb84b822 AN |
12870 | int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms) |
12871 | { | |
12872 | int i, cnt, err; | |
12873 | ||
12874 | cnt = epoll_wait(pb->epoll_fd, pb->events, pb->cpu_cnt, timeout_ms); | |
e9fc3ce9 | 12875 | if (cnt < 0) |
af0efa05 | 12876 | return -errno; |
e9fc3ce9 | 12877 | |
fb84b822 AN |
12878 | for (i = 0; i < cnt; i++) { |
12879 | struct perf_cpu_buf *cpu_buf = pb->events[i].data.ptr; | |
12880 | ||
12881 | err = perf_buffer__process_records(pb, cpu_buf); | |
12882 | if (err) { | |
be18010e | 12883 | pr_warn("error while processing records: %d\n", err); |
e9fc3ce9 | 12884 | return libbpf_err(err); |
fb84b822 AN |
12885 | } |
12886 | } | |
e9fc3ce9 | 12887 | return cnt; |
fb84b822 AN |
12888 | } |
12889 | ||
dca5612f AN |
12890 | /* Return number of PERF_EVENT_ARRAY map slots set up by this perf_buffer |
12891 | * manager. | |
12892 | */ | |
12893 | size_t perf_buffer__buffer_cnt(const struct perf_buffer *pb) | |
12894 | { | |
12895 | return pb->cpu_cnt; | |
12896 | } | |
12897 | ||
12898 | /* | |
12899 | * Return perf_event FD of a ring buffer in *buf_idx* slot of | |
12900 | * PERF_EVENT_ARRAY BPF map. This FD can be polled for new data using | |
12901 | * select()/poll()/epoll() Linux syscalls. | |
12902 | */ | |
12903 | int perf_buffer__buffer_fd(const struct perf_buffer *pb, size_t buf_idx) | |
12904 | { | |
12905 | struct perf_cpu_buf *cpu_buf; | |
12906 | ||
12907 | if (buf_idx >= pb->cpu_cnt) | |
e9fc3ce9 | 12908 | return libbpf_err(-EINVAL); |
dca5612f AN |
12909 | |
12910 | cpu_buf = pb->cpu_bufs[buf_idx]; | |
12911 | if (!cpu_buf) | |
e9fc3ce9 | 12912 | return libbpf_err(-ENOENT); |
dca5612f AN |
12913 | |
12914 | return cpu_buf->fd; | |
12915 | } | |
12916 | ||
9ff5efde JD |
12917 | int perf_buffer__buffer(struct perf_buffer *pb, int buf_idx, void **buf, size_t *buf_size) |
12918 | { | |
12919 | struct perf_cpu_buf *cpu_buf; | |
12920 | ||
12921 | if (buf_idx >= pb->cpu_cnt) | |
12922 | return libbpf_err(-EINVAL); | |
12923 | ||
12924 | cpu_buf = pb->cpu_bufs[buf_idx]; | |
12925 | if (!cpu_buf) | |
12926 | return libbpf_err(-ENOENT); | |
12927 | ||
12928 | *buf = cpu_buf->base; | |
12929 | *buf_size = pb->mmap_size; | |
12930 | return 0; | |
12931 | } | |
12932 | ||
dca5612f AN |
12933 | /* |
12934 | * Consume data from perf ring buffer corresponding to slot *buf_idx* in | |
12935 | * PERF_EVENT_ARRAY BPF map without waiting/polling. If there is no data to | |
12936 | * consume, do nothing and return success. | |
12937 | * Returns: | |
12938 | * - 0 on success; | |
12939 | * - <0 on failure. | |
12940 | */ | |
12941 | int perf_buffer__consume_buffer(struct perf_buffer *pb, size_t buf_idx) | |
12942 | { | |
12943 | struct perf_cpu_buf *cpu_buf; | |
12944 | ||
12945 | if (buf_idx >= pb->cpu_cnt) | |
e9fc3ce9 | 12946 | return libbpf_err(-EINVAL); |
dca5612f AN |
12947 | |
12948 | cpu_buf = pb->cpu_bufs[buf_idx]; | |
12949 | if (!cpu_buf) | |
e9fc3ce9 | 12950 | return libbpf_err(-ENOENT); |
dca5612f AN |
12951 | |
12952 | return perf_buffer__process_records(pb, cpu_buf); | |
12953 | } | |
12954 | ||
272d51af EC |
12955 | int perf_buffer__consume(struct perf_buffer *pb) |
12956 | { | |
12957 | int i, err; | |
12958 | ||
12959 | for (i = 0; i < pb->cpu_cnt; i++) { | |
12960 | struct perf_cpu_buf *cpu_buf = pb->cpu_bufs[i]; | |
12961 | ||
12962 | if (!cpu_buf) | |
12963 | continue; | |
12964 | ||
12965 | err = perf_buffer__process_records(pb, cpu_buf); | |
12966 | if (err) { | |
dca5612f | 12967 | pr_warn("perf_buffer: failed to process records in buffer #%d: %d\n", i, err); |
e9fc3ce9 | 12968 | return libbpf_err(err); |
272d51af EC |
12969 | } |
12970 | } | |
12971 | return 0; | |
12972 | } | |
12973 | ||
ff26ce5c EC |
12974 | int bpf_program__set_attach_target(struct bpf_program *prog, |
12975 | int attach_prog_fd, | |
12976 | const char *attach_func_name) | |
12977 | { | |
fe62de31 | 12978 | int btf_obj_fd = 0, btf_id = 0, err; |
ff26ce5c | 12979 | |
2d5ec1c6 | 12980 | if (!prog || attach_prog_fd < 0) |
e9fc3ce9 | 12981 | return libbpf_err(-EINVAL); |
ff26ce5c | 12982 | |
fe62de31 | 12983 | if (prog->obj->loaded) |
e9fc3ce9 | 12984 | return libbpf_err(-EINVAL); |
fe62de31 | 12985 | |
2d5ec1c6 AN |
12986 | if (attach_prog_fd && !attach_func_name) { |
12987 | /* remember attach_prog_fd and let bpf_program__load() find | |
12988 | * BTF ID during the program load | |
12989 | */ | |
12990 | prog->attach_prog_fd = attach_prog_fd; | |
12991 | return 0; | |
12992 | } | |
12993 | ||
fe62de31 | 12994 | if (attach_prog_fd) { |
ff26ce5c EC |
12995 | btf_id = libbpf_find_prog_btf_id(attach_func_name, |
12996 | attach_prog_fd); | |
fe62de31 | 12997 | if (btf_id < 0) |
e9fc3ce9 | 12998 | return libbpf_err(btf_id); |
fe62de31 | 12999 | } else { |
2d5ec1c6 AN |
13000 | if (!attach_func_name) |
13001 | return libbpf_err(-EINVAL); | |
13002 | ||
fe62de31 AN |
13003 | /* load btf_vmlinux, if not yet */ |
13004 | err = bpf_object__load_vmlinux_btf(prog->obj, true); | |
13005 | if (err) | |
e9fc3ce9 | 13006 | return libbpf_err(err); |
fe62de31 AN |
13007 | err = find_kernel_btf_id(prog->obj, attach_func_name, |
13008 | prog->expected_attach_type, | |
13009 | &btf_obj_fd, &btf_id); | |
13010 | if (err) | |
e9fc3ce9 | 13011 | return libbpf_err(err); |
fe62de31 | 13012 | } |
ff26ce5c EC |
13013 | |
13014 | prog->attach_btf_id = btf_id; | |
fe62de31 | 13015 | prog->attach_btf_obj_fd = btf_obj_fd; |
ff26ce5c EC |
13016 | prog->attach_prog_fd = attach_prog_fd; |
13017 | return 0; | |
13018 | } | |
13019 | ||
6803ee25 | 13020 | int parse_cpu_mask_str(const char *s, bool **mask, int *mask_sz) |
6446b315 | 13021 | { |
6803ee25 AN |
13022 | int err = 0, n, len, start, end = -1; |
13023 | bool *tmp; | |
6446b315 | 13024 | |
6803ee25 AN |
13025 | *mask = NULL; |
13026 | *mask_sz = 0; | |
13027 | ||
13028 | /* Each sub string separated by ',' has format \d+-\d+ or \d+ */ | |
13029 | while (*s) { | |
13030 | if (*s == ',' || *s == '\n') { | |
13031 | s++; | |
13032 | continue; | |
13033 | } | |
13034 | n = sscanf(s, "%d%n-%d%n", &start, &len, &end, &len); | |
13035 | if (n <= 0 || n > 2) { | |
13036 | pr_warn("Failed to get CPU range %s: %d\n", s, n); | |
13037 | err = -EINVAL; | |
13038 | goto cleanup; | |
13039 | } else if (n == 1) { | |
13040 | end = start; | |
13041 | } | |
13042 | if (start < 0 || start > end) { | |
13043 | pr_warn("Invalid CPU range [%d,%d] in %s\n", | |
13044 | start, end, s); | |
13045 | err = -EINVAL; | |
13046 | goto cleanup; | |
13047 | } | |
13048 | tmp = realloc(*mask, end + 1); | |
13049 | if (!tmp) { | |
13050 | err = -ENOMEM; | |
13051 | goto cleanup; | |
13052 | } | |
13053 | *mask = tmp; | |
13054 | memset(tmp + *mask_sz, 0, start - *mask_sz); | |
13055 | memset(tmp + start, 1, end - start + 1); | |
13056 | *mask_sz = end + 1; | |
13057 | s += len; | |
13058 | } | |
13059 | if (!*mask_sz) { | |
13060 | pr_warn("Empty CPU range\n"); | |
13061 | return -EINVAL; | |
13062 | } | |
13063 | return 0; | |
13064 | cleanup: | |
13065 | free(*mask); | |
13066 | *mask = NULL; | |
13067 | return err; | |
13068 | } | |
13069 | ||
13070 | int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz) | |
13071 | { | |
13072 | int fd, err = 0, len; | |
13073 | char buf[128]; | |
6446b315 | 13074 | |
92274e24 | 13075 | fd = open(fcpu, O_RDONLY | O_CLOEXEC); |
6446b315 | 13076 | if (fd < 0) { |
6803ee25 AN |
13077 | err = -errno; |
13078 | pr_warn("Failed to open cpu mask file %s: %d\n", fcpu, err); | |
13079 | return err; | |
6446b315 HL |
13080 | } |
13081 | len = read(fd, buf, sizeof(buf)); | |
13082 | close(fd); | |
13083 | if (len <= 0) { | |
6803ee25 AN |
13084 | err = len ? -errno : -EINVAL; |
13085 | pr_warn("Failed to read cpu mask from %s: %d\n", fcpu, err); | |
13086 | return err; | |
6446b315 | 13087 | } |
6803ee25 AN |
13088 | if (len >= sizeof(buf)) { |
13089 | pr_warn("CPU mask is too big in file %s\n", fcpu); | |
13090 | return -E2BIG; | |
6446b315 HL |
13091 | } |
13092 | buf[len] = '\0'; | |
13093 | ||
6803ee25 AN |
13094 | return parse_cpu_mask_str(buf, mask, mask_sz); |
13095 | } | |
13096 | ||
13097 | int libbpf_num_possible_cpus(void) | |
13098 | { | |
13099 | static const char *fcpu = "/sys/devices/system/cpu/possible"; | |
13100 | static int cpus; | |
13101 | int err, n, i, tmp_cpus; | |
13102 | bool *mask; | |
13103 | ||
13104 | tmp_cpus = READ_ONCE(cpus); | |
13105 | if (tmp_cpus > 0) | |
13106 | return tmp_cpus; | |
13107 | ||
13108 | err = parse_cpu_mask_file(fcpu, &mask, &n); | |
13109 | if (err) | |
e9fc3ce9 | 13110 | return libbpf_err(err); |
6803ee25 AN |
13111 | |
13112 | tmp_cpus = 0; | |
13113 | for (i = 0; i < n; i++) { | |
13114 | if (mask[i]) | |
13115 | tmp_cpus++; | |
6446b315 | 13116 | } |
6803ee25 | 13117 | free(mask); |
56fbc241 TC |
13118 | |
13119 | WRITE_ONCE(cpus, tmp_cpus); | |
13120 | return tmp_cpus; | |
6446b315 | 13121 | } |
d66562fb | 13122 | |
430025e5 DK |
13123 | static int populate_skeleton_maps(const struct bpf_object *obj, |
13124 | struct bpf_map_skeleton *maps, | |
13125 | size_t map_cnt) | |
13126 | { | |
13127 | int i; | |
13128 | ||
13129 | for (i = 0; i < map_cnt; i++) { | |
13130 | struct bpf_map **map = maps[i].map; | |
13131 | const char *name = maps[i].name; | |
13132 | void **mmaped = maps[i].mmaped; | |
13133 | ||
13134 | *map = bpf_object__find_map_by_name(obj, name); | |
13135 | if (!*map) { | |
13136 | pr_warn("failed to find skeleton map '%s'\n", name); | |
13137 | return -ESRCH; | |
13138 | } | |
13139 | ||
13140 | /* externs shouldn't be pre-setup from user code */ | |
13141 | if (mmaped && (*map)->libbpf_type != LIBBPF_MAP_KCONFIG) | |
13142 | *mmaped = (*map)->mmaped; | |
13143 | } | |
13144 | return 0; | |
13145 | } | |
13146 | ||
13147 | static int populate_skeleton_progs(const struct bpf_object *obj, | |
13148 | struct bpf_prog_skeleton *progs, | |
13149 | size_t prog_cnt) | |
13150 | { | |
13151 | int i; | |
13152 | ||
13153 | for (i = 0; i < prog_cnt; i++) { | |
13154 | struct bpf_program **prog = progs[i].prog; | |
13155 | const char *name = progs[i].name; | |
13156 | ||
13157 | *prog = bpf_object__find_program_by_name(obj, name); | |
13158 | if (!*prog) { | |
13159 | pr_warn("failed to find skeleton program '%s'\n", name); | |
13160 | return -ESRCH; | |
13161 | } | |
13162 | } | |
13163 | return 0; | |
13164 | } | |
13165 | ||
d66562fb AN |
13166 | int bpf_object__open_skeleton(struct bpf_object_skeleton *s, |
13167 | const struct bpf_object_open_opts *opts) | |
13168 | { | |
13169 | DECLARE_LIBBPF_OPTS(bpf_object_open_opts, skel_opts, | |
13170 | .object_name = s->name, | |
13171 | ); | |
13172 | struct bpf_object *obj; | |
430025e5 | 13173 | int err; |
d66562fb AN |
13174 | |
13175 | /* Attempt to preserve opts->object_name, unless overriden by user | |
13176 | * explicitly. Overwriting object name for skeletons is discouraged, | |
13177 | * as it breaks global data maps, because they contain object name | |
13178 | * prefix as their own map name prefix. When skeleton is generated, | |
13179 | * bpftool is making an assumption that this name will stay the same. | |
13180 | */ | |
13181 | if (opts) { | |
13182 | memcpy(&skel_opts, opts, sizeof(*opts)); | |
13183 | if (!opts->object_name) | |
13184 | skel_opts.object_name = s->name; | |
13185 | } | |
13186 | ||
13187 | obj = bpf_object__open_mem(s->data, s->data_sz, &skel_opts); | |
e9fc3ce9 AN |
13188 | err = libbpf_get_error(obj); |
13189 | if (err) { | |
13190 | pr_warn("failed to initialize skeleton BPF object '%s': %d\n", | |
13191 | s->name, err); | |
13192 | return libbpf_err(err); | |
d66562fb AN |
13193 | } |
13194 | ||
13195 | *s->obj = obj; | |
430025e5 DK |
13196 | err = populate_skeleton_maps(obj, s->maps, s->map_cnt); |
13197 | if (err) { | |
13198 | pr_warn("failed to populate skeleton maps for '%s': %d\n", s->name, err); | |
13199 | return libbpf_err(err); | |
13200 | } | |
13201 | ||
13202 | err = populate_skeleton_progs(obj, s->progs, s->prog_cnt); | |
13203 | if (err) { | |
13204 | pr_warn("failed to populate skeleton progs for '%s': %d\n", s->name, err); | |
13205 | return libbpf_err(err); | |
13206 | } | |
d66562fb | 13207 | |
430025e5 DK |
13208 | return 0; |
13209 | } | |
d66562fb | 13210 | |
430025e5 DK |
13211 | int bpf_object__open_subskeleton(struct bpf_object_subskeleton *s) |
13212 | { | |
13213 | int err, len, var_idx, i; | |
13214 | const char *var_name; | |
13215 | const struct bpf_map *map; | |
13216 | struct btf *btf; | |
13217 | __u32 map_type_id; | |
13218 | const struct btf_type *map_type, *var_type; | |
13219 | const struct bpf_var_skeleton *var_skel; | |
13220 | struct btf_var_secinfo *var; | |
d66562fb | 13221 | |
430025e5 DK |
13222 | if (!s->obj) |
13223 | return libbpf_err(-EINVAL); | |
13224 | ||
13225 | btf = bpf_object__btf(s->obj); | |
13226 | if (!btf) { | |
13227 | pr_warn("subskeletons require BTF at runtime (object %s)\n", | |
e3ba8e4e | 13228 | bpf_object__name(s->obj)); |
430025e5 | 13229 | return libbpf_err(-errno); |
d66562fb AN |
13230 | } |
13231 | ||
430025e5 DK |
13232 | err = populate_skeleton_maps(s->obj, s->maps, s->map_cnt); |
13233 | if (err) { | |
13234 | pr_warn("failed to populate subskeleton maps: %d\n", err); | |
13235 | return libbpf_err(err); | |
13236 | } | |
d66562fb | 13237 | |
430025e5 DK |
13238 | err = populate_skeleton_progs(s->obj, s->progs, s->prog_cnt); |
13239 | if (err) { | |
13240 | pr_warn("failed to populate subskeleton maps: %d\n", err); | |
13241 | return libbpf_err(err); | |
d66562fb AN |
13242 | } |
13243 | ||
430025e5 DK |
13244 | for (var_idx = 0; var_idx < s->var_cnt; var_idx++) { |
13245 | var_skel = &s->vars[var_idx]; | |
13246 | map = *var_skel->map; | |
13247 | map_type_id = bpf_map__btf_value_type_id(map); | |
13248 | map_type = btf__type_by_id(btf, map_type_id); | |
13249 | ||
13250 | if (!btf_is_datasec(map_type)) { | |
13251 | pr_warn("type for map '%1$s' is not a datasec: %2$s", | |
13252 | bpf_map__name(map), | |
13253 | __btf_kind_str(btf_kind(map_type))); | |
13254 | return libbpf_err(-EINVAL); | |
13255 | } | |
13256 | ||
13257 | len = btf_vlen(map_type); | |
13258 | var = btf_var_secinfos(map_type); | |
13259 | for (i = 0; i < len; i++, var++) { | |
13260 | var_type = btf__type_by_id(btf, var->type); | |
13261 | var_name = btf__name_by_offset(btf, var_type->name_off); | |
13262 | if (strcmp(var_name, var_skel->name) == 0) { | |
13263 | *var_skel->addr = map->mmaped + var->offset; | |
13264 | break; | |
13265 | } | |
13266 | } | |
13267 | } | |
d66562fb AN |
13268 | return 0; |
13269 | } | |
13270 | ||
430025e5 DK |
13271 | void bpf_object__destroy_subskeleton(struct bpf_object_subskeleton *s) |
13272 | { | |
13273 | if (!s) | |
13274 | return; | |
13275 | free(s->maps); | |
13276 | free(s->progs); | |
13277 | free(s->vars); | |
13278 | free(s); | |
13279 | } | |
13280 | ||
d66562fb AN |
13281 | int bpf_object__load_skeleton(struct bpf_object_skeleton *s) |
13282 | { | |
13283 | int i, err; | |
13284 | ||
13285 | err = bpf_object__load(*s->obj); | |
13286 | if (err) { | |
13287 | pr_warn("failed to load BPF skeleton '%s': %d\n", s->name, err); | |
e9fc3ce9 | 13288 | return libbpf_err(err); |
d66562fb AN |
13289 | } |
13290 | ||
13291 | for (i = 0; i < s->map_cnt; i++) { | |
13292 | struct bpf_map *map = *s->maps[i].map; | |
9d0a2331 | 13293 | size_t mmap_sz = bpf_map_mmap_sz(map->def.value_size, map->def.max_entries); |
d66562fb AN |
13294 | int prot, map_fd = bpf_map__fd(map); |
13295 | void **mmaped = s->maps[i].mmaped; | |
d66562fb AN |
13296 | |
13297 | if (!mmaped) | |
13298 | continue; | |
13299 | ||
13300 | if (!(map->def.map_flags & BPF_F_MMAPABLE)) { | |
13301 | *mmaped = NULL; | |
13302 | continue; | |
13303 | } | |
13304 | ||
13305 | if (map->def.map_flags & BPF_F_RDONLY_PROG) | |
13306 | prot = PROT_READ; | |
13307 | else | |
13308 | prot = PROT_READ | PROT_WRITE; | |
13309 | ||
13310 | /* Remap anonymous mmap()-ed "map initialization image" as | |
13311 | * a BPF map-backed mmap()-ed memory, but preserving the same | |
13312 | * memory address. This will cause kernel to change process' | |
13313 | * page table to point to a different piece of kernel memory, | |
13314 | * but from userspace point of view memory address (and its | |
13315 | * contents, being identical at this point) will stay the | |
13316 | * same. This mapping will be released by bpf_object__close() | |
13317 | * as per normal clean up procedure, so we don't need to worry | |
13318 | * about it from skeleton's clean up perspective. | |
13319 | */ | |
9d0a2331 | 13320 | *mmaped = mmap(map->mmaped, mmap_sz, prot, MAP_SHARED | MAP_FIXED, map_fd, 0); |
2ad97d47 | 13321 | if (*mmaped == MAP_FAILED) { |
d66562fb AN |
13322 | err = -errno; |
13323 | *mmaped = NULL; | |
13324 | pr_warn("failed to re-mmap() map '%s': %d\n", | |
13325 | bpf_map__name(map), err); | |
e9fc3ce9 | 13326 | return libbpf_err(err); |
d66562fb AN |
13327 | } |
13328 | } | |
13329 | ||
13330 | return 0; | |
13331 | } | |
13332 | ||
13333 | int bpf_object__attach_skeleton(struct bpf_object_skeleton *s) | |
13334 | { | |
e9fc3ce9 | 13335 | int i, err; |
d66562fb AN |
13336 | |
13337 | for (i = 0; i < s->prog_cnt; i++) { | |
13338 | struct bpf_program *prog = *s->progs[i].prog; | |
13339 | struct bpf_link **link = s->progs[i].link; | |
d66562fb | 13340 | |
43cb8cba | 13341 | if (!prog->autoload || !prog->autoattach) |
d9297581 AN |
13342 | continue; |
13343 | ||
5532dfd4 | 13344 | /* auto-attaching not supported for this program */ |
4fa5bcfe | 13345 | if (!prog->sec_def || !prog->sec_def->prog_attach_fn) |
d66562fb AN |
13346 | continue; |
13347 | ||
4fa5bcfe AN |
13348 | /* if user already set the link manually, don't attempt auto-attach */ |
13349 | if (*link) | |
13350 | continue; | |
13351 | ||
13352 | err = prog->sec_def->prog_attach_fn(prog, prog->sec_def->cookie, link); | |
e9fc3ce9 | 13353 | if (err) { |
4fa5bcfe | 13354 | pr_warn("prog '%s': failed to auto-attach: %d\n", |
e9fc3ce9 AN |
13355 | bpf_program__name(prog), err); |
13356 | return libbpf_err(err); | |
d66562fb | 13357 | } |
4fa5bcfe AN |
13358 | |
13359 | /* It's possible that for some SEC() definitions auto-attach | |
13360 | * is supported in some cases (e.g., if definition completely | |
13361 | * specifies target information), but is not in other cases. | |
13362 | * SEC("uprobe") is one such case. If user specified target | |
13363 | * binary and function name, such BPF program can be | |
13364 | * auto-attached. But if not, it shouldn't trigger skeleton's | |
13365 | * attach to fail. It should just be skipped. | |
13366 | * attach_fn signals such case with returning 0 (no error) and | |
13367 | * setting link to NULL. | |
13368 | */ | |
d66562fb AN |
13369 | } |
13370 | ||
13371 | return 0; | |
13372 | } | |
13373 | ||
13374 | void bpf_object__detach_skeleton(struct bpf_object_skeleton *s) | |
13375 | { | |
13376 | int i; | |
13377 | ||
13378 | for (i = 0; i < s->prog_cnt; i++) { | |
13379 | struct bpf_link **link = s->progs[i].link; | |
13380 | ||
50450fc7 | 13381 | bpf_link__destroy(*link); |
d66562fb AN |
13382 | *link = NULL; |
13383 | } | |
13384 | } | |
13385 | ||
13386 | void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s) | |
13387 | { | |
a32ea51a YS |
13388 | if (!s) |
13389 | return; | |
13390 | ||
d66562fb AN |
13391 | if (s->progs) |
13392 | bpf_object__detach_skeleton(s); | |
13393 | if (s->obj) | |
13394 | bpf_object__close(*s->obj); | |
13395 | free(s->maps); | |
13396 | free(s->progs); | |
13397 | free(s); | |
13398 | } |