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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> |
9a208eff | 34 | #include <linux/list.h> |
f367540c | 35 | #include <linux/limits.h> |
438363c0 | 36 | #include <linux/perf_event.h> |
a64af0ef | 37 | #include <linux/ring_buffer.h> |
5e61f270 | 38 | #include <linux/version.h> |
fb84b822 | 39 | #include <sys/epoll.h> |
63f2f5ee | 40 | #include <sys/ioctl.h> |
fb84b822 | 41 | #include <sys/mman.h> |
f367540c JS |
42 | #include <sys/stat.h> |
43 | #include <sys/types.h> | |
44 | #include <sys/vfs.h> | |
ddc7c304 | 45 | #include <sys/utsname.h> |
dc3a2d25 | 46 | #include <sys/resource.h> |
1a5e3fb1 WN |
47 | #include <libelf.h> |
48 | #include <gelf.h> | |
166750bc | 49 | #include <zlib.h> |
1b76c13e WN |
50 | |
51 | #include "libbpf.h" | |
52d3352e | 52 | #include "bpf.h" |
8a138aed | 53 | #include "btf.h" |
6d41907c | 54 | #include "str_error.h" |
d7c4b398 | 55 | #include "libbpf_internal.h" |
ddc7c304 | 56 | #include "hashmap.h" |
b3f59d66 | 57 | |
9b16137a WN |
58 | #ifndef EM_BPF |
59 | #define EM_BPF 247 | |
60 | #endif | |
61 | ||
f367540c JS |
62 | #ifndef BPF_FS_MAGIC |
63 | #define BPF_FS_MAGIC 0xcafe4a11 | |
64 | #endif | |
65 | ||
9c0f8cbd AN |
66 | #define BPF_INSN_SZ (sizeof(struct bpf_insn)) |
67 | ||
ff466b58 AI |
68 | /* vsprintf() in __base_pr() uses nonliteral format string. It may break |
69 | * compilation if user enables corresponding warning. Disable it explicitly. | |
70 | */ | |
71 | #pragma GCC diagnostic ignored "-Wformat-nonliteral" | |
72 | ||
b3f59d66 WN |
73 | #define __printf(a, b) __attribute__((format(printf, a, b))) |
74 | ||
590a0088 | 75 | static struct bpf_map *bpf_object__add_map(struct bpf_object *obj); |
590a0088 MKL |
76 | static const struct btf_type * |
77 | skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id); | |
78 | ||
a8a1f7d0 SF |
79 | static int __base_pr(enum libbpf_print_level level, const char *format, |
80 | va_list args) | |
b3f59d66 | 81 | { |
6f1ae8b6 YS |
82 | if (level == LIBBPF_DEBUG) |
83 | return 0; | |
84 | ||
a8a1f7d0 | 85 | return vfprintf(stderr, format, args); |
b3f59d66 WN |
86 | } |
87 | ||
a8a1f7d0 | 88 | static libbpf_print_fn_t __libbpf_pr = __base_pr; |
b3f59d66 | 89 | |
e87fd8ba | 90 | libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn) |
b3f59d66 | 91 | { |
e87fd8ba AN |
92 | libbpf_print_fn_t old_print_fn = __libbpf_pr; |
93 | ||
6f1ae8b6 | 94 | __libbpf_pr = fn; |
e87fd8ba | 95 | return old_print_fn; |
b3f59d66 | 96 | } |
1a5e3fb1 | 97 | |
8461ef8b YS |
98 | __printf(2, 3) |
99 | void libbpf_print(enum libbpf_print_level level, const char *format, ...) | |
100 | { | |
101 | va_list args; | |
102 | ||
6f1ae8b6 YS |
103 | if (!__libbpf_pr) |
104 | return; | |
105 | ||
8461ef8b | 106 | va_start(args, format); |
6f1ae8b6 | 107 | __libbpf_pr(level, format, args); |
8461ef8b YS |
108 | va_end(args); |
109 | } | |
110 | ||
dc3a2d25 THJ |
111 | static void pr_perm_msg(int err) |
112 | { | |
113 | struct rlimit limit; | |
114 | char buf[100]; | |
115 | ||
116 | if (err != -EPERM || geteuid() != 0) | |
117 | return; | |
118 | ||
119 | err = getrlimit(RLIMIT_MEMLOCK, &limit); | |
120 | if (err) | |
121 | return; | |
122 | ||
123 | if (limit.rlim_cur == RLIM_INFINITY) | |
124 | return; | |
125 | ||
126 | if (limit.rlim_cur < 1024) | |
b5c7d0d0 | 127 | snprintf(buf, sizeof(buf), "%zu bytes", (size_t)limit.rlim_cur); |
dc3a2d25 THJ |
128 | else if (limit.rlim_cur < 1024*1024) |
129 | snprintf(buf, sizeof(buf), "%.1f KiB", (double)limit.rlim_cur / 1024); | |
130 | else | |
131 | snprintf(buf, sizeof(buf), "%.1f MiB", (double)limit.rlim_cur / (1024*1024)); | |
132 | ||
133 | pr_warn("permission error while running as root; try raising 'ulimit -l'? current value: %s\n", | |
134 | buf); | |
135 | } | |
136 | ||
6371ca3b WN |
137 | #define STRERR_BUFSIZE 128 |
138 | ||
1a5e3fb1 WN |
139 | /* Copied from tools/perf/util/util.h */ |
140 | #ifndef zfree | |
141 | # define zfree(ptr) ({ free(*ptr); *ptr = NULL; }) | |
142 | #endif | |
143 | ||
144 | #ifndef zclose | |
145 | # define zclose(fd) ({ \ | |
146 | int ___err = 0; \ | |
147 | if ((fd) >= 0) \ | |
148 | ___err = close((fd)); \ | |
149 | fd = -1; \ | |
150 | ___err; }) | |
151 | #endif | |
152 | ||
34be1646 SL |
153 | static inline __u64 ptr_to_u64(const void *ptr) |
154 | { | |
155 | return (__u64) (unsigned long) ptr; | |
156 | } | |
157 | ||
47b6cb4d | 158 | enum kern_feature_id { |
47eff617 | 159 | /* v4.14: kernel support for program & map names. */ |
47b6cb4d | 160 | FEAT_PROG_NAME, |
8837fe5d | 161 | /* v5.2: kernel support for global data sections. */ |
47b6cb4d | 162 | FEAT_GLOBAL_DATA, |
68b08647 AN |
163 | /* BTF support */ |
164 | FEAT_BTF, | |
d7c4b398 | 165 | /* BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO support */ |
47b6cb4d | 166 | FEAT_BTF_FUNC, |
d7c4b398 | 167 | /* BTF_KIND_VAR and BTF_KIND_DATASEC support */ |
47b6cb4d | 168 | FEAT_BTF_DATASEC, |
2d3eb67f | 169 | /* BTF_FUNC_GLOBAL is supported */ |
47b6cb4d AN |
170 | FEAT_BTF_GLOBAL_FUNC, |
171 | /* BPF_F_MMAPABLE is supported for arrays */ | |
172 | FEAT_ARRAY_MMAP, | |
25498a19 | 173 | /* kernel support for expected_attach_type in BPF_PROG_LOAD */ |
47b6cb4d | 174 | FEAT_EXP_ATTACH_TYPE, |
109cea5a AN |
175 | /* bpf_probe_read_{kernel,user}[_str] helpers */ |
176 | FEAT_PROBE_READ_KERN, | |
5d23328d YZ |
177 | /* BPF_PROG_BIND_MAP is supported */ |
178 | FEAT_PROG_BIND_MAP, | |
4f33a53d AN |
179 | /* Kernel support for module BTFs */ |
180 | FEAT_MODULE_BTF, | |
47b6cb4d | 181 | __FEAT_CNT, |
47eff617 SF |
182 | }; |
183 | ||
47b6cb4d AN |
184 | static bool kernel_supports(enum kern_feature_id feat_id); |
185 | ||
166750bc AN |
186 | enum reloc_type { |
187 | RELO_LD64, | |
188 | RELO_CALL, | |
189 | RELO_DATA, | |
190 | RELO_EXTERN, | |
191 | }; | |
192 | ||
193 | struct reloc_desc { | |
194 | enum reloc_type type; | |
195 | int insn_idx; | |
196 | int map_idx; | |
197 | int sym_off; | |
c3c55696 | 198 | bool processed; |
166750bc AN |
199 | }; |
200 | ||
25498a19 AN |
201 | struct bpf_sec_def; |
202 | ||
203 | typedef struct bpf_link *(*attach_fn_t)(const struct bpf_sec_def *sec, | |
204 | struct bpf_program *prog); | |
205 | ||
206 | struct bpf_sec_def { | |
207 | const char *sec; | |
208 | size_t len; | |
209 | enum bpf_prog_type prog_type; | |
210 | enum bpf_attach_type expected_attach_type; | |
211 | bool is_exp_attach_type_optional; | |
212 | bool is_attachable; | |
213 | bool is_attach_btf; | |
2b288740 | 214 | bool is_sleepable; |
25498a19 AN |
215 | attach_fn_t attach_fn; |
216 | }; | |
217 | ||
a5b8bd47 WN |
218 | /* |
219 | * bpf_prog should be a better name but it has been used in | |
220 | * linux/filter.h. | |
221 | */ | |
222 | struct bpf_program { | |
25498a19 | 223 | const struct bpf_sec_def *sec_def; |
52109584 | 224 | char *sec_name; |
c1122392 AN |
225 | size_t sec_idx; |
226 | /* this program's instruction offset (in number of instructions) | |
227 | * within its containing ELF section | |
228 | */ | |
229 | size_t sec_insn_off; | |
230 | /* number of original instructions in ELF section belonging to this | |
231 | * program, not taking into account subprogram instructions possible | |
232 | * appended later during relocation | |
233 | */ | |
234 | size_t sec_insn_cnt; | |
235 | /* Offset (in number of instructions) of the start of instruction | |
236 | * belonging to this BPF program within its containing main BPF | |
237 | * program. For the entry-point (main) BPF program, this is always | |
238 | * zero. For a sub-program, this gets reset before each of main BPF | |
239 | * programs are processed and relocated and is used to determined | |
240 | * whether sub-program was already appended to the main program, and | |
241 | * if yes, at which instruction offset. | |
242 | */ | |
243 | size_t sub_insn_off; | |
244 | ||
245 | char *name; | |
52109584 | 246 | /* sec_name with / replaced by _; makes recursive pinning |
33a2c75c SF |
247 | * in bpf_object__pin_programs easier |
248 | */ | |
249 | char *pin_name; | |
c1122392 AN |
250 | |
251 | /* instructions that belong to BPF program; insns[0] is located at | |
252 | * sec_insn_off instruction within its ELF section in ELF file, so | |
253 | * when mapping ELF file instruction index to the local instruction, | |
254 | * one needs to subtract sec_insn_off; and vice versa. | |
255 | */ | |
a5b8bd47 | 256 | struct bpf_insn *insns; |
c1122392 AN |
257 | /* actual number of instruction in this BPF program's image; for |
258 | * entry-point BPF programs this includes the size of main program | |
259 | * itself plus all the used sub-programs, appended at the end | |
260 | */ | |
c3c55696 | 261 | size_t insns_cnt; |
34090915 | 262 | |
166750bc | 263 | struct reloc_desc *reloc_desc; |
34090915 | 264 | int nr_reloc; |
da11b417 | 265 | int log_level; |
55cffde2 | 266 | |
b580563e WN |
267 | struct { |
268 | int nr; | |
269 | int *fds; | |
270 | } instances; | |
271 | bpf_program_prep_t preprocessor; | |
aa9b1ac3 WN |
272 | |
273 | struct bpf_object *obj; | |
274 | void *priv; | |
275 | bpf_program_clear_priv_t clear_priv; | |
d7be143b | 276 | |
c1122392 AN |
277 | bool load; |
278 | enum bpf_prog_type type; | |
d7be143b | 279 | enum bpf_attach_type expected_attach_type; |
c1122392 | 280 | int prog_ifindex; |
91abb4a6 | 281 | __u32 attach_btf_obj_fd; |
12a8654b | 282 | __u32 attach_btf_id; |
e7bf94db | 283 | __u32 attach_prog_fd; |
2993e051 YS |
284 | void *func_info; |
285 | __u32 func_info_rec_size; | |
f0187f0b | 286 | __u32 func_info_cnt; |
47eff617 | 287 | |
3d650141 MKL |
288 | void *line_info; |
289 | __u32 line_info_rec_size; | |
290 | __u32 line_info_cnt; | |
04656198 | 291 | __u32 prog_flags; |
a5b8bd47 WN |
292 | }; |
293 | ||
590a0088 MKL |
294 | struct bpf_struct_ops { |
295 | const char *tname; | |
296 | const struct btf_type *type; | |
297 | struct bpf_program **progs; | |
298 | __u32 *kern_func_off; | |
299 | /* e.g. struct tcp_congestion_ops in bpf_prog's btf format */ | |
300 | void *data; | |
301 | /* e.g. struct bpf_struct_ops_tcp_congestion_ops in | |
302 | * btf_vmlinux's format. | |
303 | * struct bpf_struct_ops_tcp_congestion_ops { | |
304 | * [... some other kernel fields ...] | |
305 | * struct tcp_congestion_ops data; | |
306 | * } | |
307 | * kern_vdata-size == sizeof(struct bpf_struct_ops_tcp_congestion_ops) | |
308 | * bpf_map__init_kern_struct_ops() will populate the "kern_vdata" | |
309 | * from "data". | |
310 | */ | |
311 | void *kern_vdata; | |
312 | __u32 type_id; | |
313 | }; | |
314 | ||
ac9d1389 AN |
315 | #define DATA_SEC ".data" |
316 | #define BSS_SEC ".bss" | |
317 | #define RODATA_SEC ".rodata" | |
81bfdd08 | 318 | #define KCONFIG_SEC ".kconfig" |
1c0c7074 | 319 | #define KSYMS_SEC ".ksyms" |
590a0088 | 320 | #define STRUCT_OPS_SEC ".struct_ops" |
ac9d1389 | 321 | |
d859900c DB |
322 | enum libbpf_map_type { |
323 | LIBBPF_MAP_UNSPEC, | |
324 | LIBBPF_MAP_DATA, | |
325 | LIBBPF_MAP_BSS, | |
326 | LIBBPF_MAP_RODATA, | |
81bfdd08 | 327 | LIBBPF_MAP_KCONFIG, |
d859900c DB |
328 | }; |
329 | ||
330 | static const char * const libbpf_type_to_btf_name[] = { | |
ac9d1389 AN |
331 | [LIBBPF_MAP_DATA] = DATA_SEC, |
332 | [LIBBPF_MAP_BSS] = BSS_SEC, | |
333 | [LIBBPF_MAP_RODATA] = RODATA_SEC, | |
81bfdd08 | 334 | [LIBBPF_MAP_KCONFIG] = KCONFIG_SEC, |
d859900c DB |
335 | }; |
336 | ||
9d759a9b | 337 | struct bpf_map { |
561bbcca | 338 | char *name; |
01af3bf0 | 339 | int fd; |
db48814b AN |
340 | int sec_idx; |
341 | size_t sec_offset; | |
f0307a7e | 342 | int map_ifindex; |
addb9fc9 | 343 | int inner_map_fd; |
9d759a9b | 344 | struct bpf_map_def def; |
1bdb6c9a | 345 | __u32 numa_node; |
646f02ff | 346 | __u32 btf_var_idx; |
5b891af7 MKL |
347 | __u32 btf_key_type_id; |
348 | __u32 btf_value_type_id; | |
590a0088 | 349 | __u32 btf_vmlinux_value_type_id; |
9d759a9b WN |
350 | void *priv; |
351 | bpf_map_clear_priv_t clear_priv; | |
d859900c | 352 | enum libbpf_map_type libbpf_type; |
eba9c5f4 | 353 | void *mmaped; |
590a0088 | 354 | struct bpf_struct_ops *st_ops; |
646f02ff AN |
355 | struct bpf_map *inner_map; |
356 | void **init_slots; | |
357 | int init_slots_sz; | |
4580b25f THJ |
358 | char *pin_path; |
359 | bool pinned; | |
ec6d5f47 | 360 | bool reused; |
d859900c DB |
361 | }; |
362 | ||
166750bc AN |
363 | enum extern_type { |
364 | EXT_UNKNOWN, | |
2e33efe3 | 365 | EXT_KCFG, |
1c0c7074 | 366 | EXT_KSYM, |
2e33efe3 AN |
367 | }; |
368 | ||
369 | enum kcfg_type { | |
370 | KCFG_UNKNOWN, | |
371 | KCFG_CHAR, | |
372 | KCFG_BOOL, | |
373 | KCFG_INT, | |
374 | KCFG_TRISTATE, | |
375 | KCFG_CHAR_ARR, | |
166750bc AN |
376 | }; |
377 | ||
378 | struct extern_desc { | |
2e33efe3 | 379 | enum extern_type type; |
166750bc AN |
380 | int sym_idx; |
381 | int btf_id; | |
2e33efe3 AN |
382 | int sec_btf_id; |
383 | const char *name; | |
166750bc | 384 | bool is_set; |
2e33efe3 AN |
385 | bool is_weak; |
386 | union { | |
387 | struct { | |
388 | enum kcfg_type type; | |
389 | int sz; | |
390 | int align; | |
391 | int data_off; | |
392 | bool is_signed; | |
393 | } kcfg; | |
1c0c7074 AN |
394 | struct { |
395 | unsigned long long addr; | |
d370bbe1 HL |
396 | |
397 | /* target btf_id of the corresponding kernel var. */ | |
398 | int vmlinux_btf_id; | |
399 | ||
400 | /* local btf_id of the ksym extern's type. */ | |
401 | __u32 type_id; | |
1c0c7074 | 402 | } ksym; |
2e33efe3 | 403 | }; |
166750bc AN |
404 | }; |
405 | ||
9a208eff WN |
406 | static LIST_HEAD(bpf_objects_list); |
407 | ||
4f33a53d AN |
408 | struct module_btf { |
409 | struct btf *btf; | |
410 | char *name; | |
411 | __u32 id; | |
91abb4a6 | 412 | int fd; |
4f33a53d AN |
413 | }; |
414 | ||
1a5e3fb1 | 415 | struct bpf_object { |
d859900c | 416 | char name[BPF_OBJ_NAME_LEN]; |
cb1e5e96 | 417 | char license[64]; |
438363c0 | 418 | __u32 kern_version; |
0b3d1efa | 419 | |
a5b8bd47 WN |
420 | struct bpf_program *programs; |
421 | size_t nr_programs; | |
9d759a9b WN |
422 | struct bpf_map *maps; |
423 | size_t nr_maps; | |
bf829271 | 424 | size_t maps_cap; |
9d759a9b | 425 | |
8601fd42 | 426 | char *kconfig; |
166750bc AN |
427 | struct extern_desc *externs; |
428 | int nr_extern; | |
81bfdd08 | 429 | int kconfig_map_idx; |
5d23328d | 430 | int rodata_map_idx; |
166750bc | 431 | |
52d3352e | 432 | bool loaded; |
c3c55696 | 433 | bool has_subcalls; |
a5b8bd47 | 434 | |
1a5e3fb1 WN |
435 | /* |
436 | * Information when doing elf related work. Only valid if fd | |
437 | * is valid. | |
438 | */ | |
439 | struct { | |
440 | int fd; | |
5e61f270 | 441 | const void *obj_buf; |
6c956392 | 442 | size_t obj_buf_sz; |
1a5e3fb1 WN |
443 | Elf *elf; |
444 | GElf_Ehdr ehdr; | |
bec7d68c | 445 | Elf_Data *symbols; |
d859900c DB |
446 | Elf_Data *data; |
447 | Elf_Data *rodata; | |
448 | Elf_Data *bss; | |
590a0088 | 449 | Elf_Data *st_ops_data; |
88a82120 | 450 | size_t shstrndx; /* section index for section name strings */ |
77ba9a5b | 451 | size_t strtabidx; |
b62f06e8 WN |
452 | struct { |
453 | GElf_Shdr shdr; | |
454 | Elf_Data *data; | |
1f8e2bcb AN |
455 | } *reloc_sects; |
456 | int nr_reloc_sects; | |
666810e8 | 457 | int maps_shndx; |
abd29c93 | 458 | int btf_maps_shndx; |
646f02ff | 459 | __u32 btf_maps_sec_btf_id; |
48cca7e4 | 460 | int text_shndx; |
166750bc | 461 | int symbols_shndx; |
d859900c DB |
462 | int data_shndx; |
463 | int rodata_shndx; | |
464 | int bss_shndx; | |
590a0088 | 465 | int st_ops_shndx; |
1a5e3fb1 | 466 | } efile; |
9a208eff WN |
467 | /* |
468 | * All loaded bpf_object is linked in a list, which is | |
469 | * hidden to caller. bpf_objects__<func> handlers deal with | |
470 | * all objects. | |
471 | */ | |
472 | struct list_head list; | |
10931d24 | 473 | |
8a138aed | 474 | struct btf *btf; |
0f7515ca AN |
475 | struct btf_ext *btf_ext; |
476 | ||
a6ed02ca KS |
477 | /* Parse and load BTF vmlinux if any of the programs in the object need |
478 | * it at load time. | |
479 | */ | |
480 | struct btf *btf_vmlinux; | |
0f7515ca AN |
481 | /* vmlinux BTF override for CO-RE relocations */ |
482 | struct btf *btf_vmlinux_override; | |
4f33a53d AN |
483 | /* Lazily initialized kernel module BTFs */ |
484 | struct module_btf *btf_modules; | |
485 | bool btf_modules_loaded; | |
486 | size_t btf_module_cnt; | |
487 | size_t btf_module_cap; | |
8a138aed | 488 | |
10931d24 WN |
489 | void *priv; |
490 | bpf_object_clear_priv_t clear_priv; | |
491 | ||
1a5e3fb1 WN |
492 | char path[]; |
493 | }; | |
494 | #define obj_elf_valid(o) ((o)->efile.elf) | |
495 | ||
88a82120 AN |
496 | static const char *elf_sym_str(const struct bpf_object *obj, size_t off); |
497 | static const char *elf_sec_str(const struct bpf_object *obj, size_t off); | |
498 | static Elf_Scn *elf_sec_by_idx(const struct bpf_object *obj, size_t idx); | |
499 | static Elf_Scn *elf_sec_by_name(const struct bpf_object *obj, const char *name); | |
500 | static int elf_sec_hdr(const struct bpf_object *obj, Elf_Scn *scn, GElf_Shdr *hdr); | |
501 | static const char *elf_sec_name(const struct bpf_object *obj, Elf_Scn *scn); | |
502 | static Elf_Data *elf_sec_data(const struct bpf_object *obj, Elf_Scn *scn); | |
c1122392 AN |
503 | static int elf_sym_by_sec_off(const struct bpf_object *obj, size_t sec_idx, |
504 | size_t off, __u32 sym_type, GElf_Sym *sym); | |
88a82120 | 505 | |
29cd77f4 | 506 | void bpf_program__unload(struct bpf_program *prog) |
55cffde2 | 507 | { |
b580563e WN |
508 | int i; |
509 | ||
55cffde2 WN |
510 | if (!prog) |
511 | return; | |
512 | ||
b580563e WN |
513 | /* |
514 | * If the object is opened but the program was never loaded, | |
515 | * it is possible that prog->instances.nr == -1. | |
516 | */ | |
517 | if (prog->instances.nr > 0) { | |
518 | for (i = 0; i < prog->instances.nr; i++) | |
519 | zclose(prog->instances.fds[i]); | |
520 | } else if (prog->instances.nr != -1) { | |
be18010e KW |
521 | pr_warn("Internal error: instances.nr is %d\n", |
522 | prog->instances.nr); | |
b580563e WN |
523 | } |
524 | ||
525 | prog->instances.nr = -1; | |
526 | zfree(&prog->instances.fds); | |
2993e051 | 527 | |
2993e051 | 528 | zfree(&prog->func_info); |
07a09d1b | 529 | zfree(&prog->line_info); |
55cffde2 WN |
530 | } |
531 | ||
a5b8bd47 WN |
532 | static void bpf_program__exit(struct bpf_program *prog) |
533 | { | |
534 | if (!prog) | |
535 | return; | |
536 | ||
aa9b1ac3 WN |
537 | if (prog->clear_priv) |
538 | prog->clear_priv(prog, prog->priv); | |
539 | ||
540 | prog->priv = NULL; | |
541 | prog->clear_priv = NULL; | |
542 | ||
55cffde2 | 543 | bpf_program__unload(prog); |
88cda1c9 | 544 | zfree(&prog->name); |
52109584 | 545 | zfree(&prog->sec_name); |
33a2c75c | 546 | zfree(&prog->pin_name); |
a5b8bd47 | 547 | zfree(&prog->insns); |
34090915 WN |
548 | zfree(&prog->reloc_desc); |
549 | ||
550 | prog->nr_reloc = 0; | |
a5b8bd47 | 551 | prog->insns_cnt = 0; |
c1122392 | 552 | prog->sec_idx = -1; |
a5b8bd47 WN |
553 | } |
554 | ||
33a2c75c SF |
555 | static char *__bpf_program__pin_name(struct bpf_program *prog) |
556 | { | |
557 | char *name, *p; | |
558 | ||
52109584 | 559 | name = p = strdup(prog->sec_name); |
33a2c75c SF |
560 | while ((p = strchr(p, '/'))) |
561 | *p = '_'; | |
562 | ||
563 | return name; | |
564 | } | |
565 | ||
c3c55696 AN |
566 | static bool insn_is_subprog_call(const struct bpf_insn *insn) |
567 | { | |
568 | return BPF_CLASS(insn->code) == BPF_JMP && | |
569 | BPF_OP(insn->code) == BPF_CALL && | |
570 | BPF_SRC(insn->code) == BPF_K && | |
571 | insn->src_reg == BPF_PSEUDO_CALL && | |
572 | insn->dst_reg == 0 && | |
573 | insn->off == 0; | |
574 | } | |
575 | ||
a5b8bd47 | 576 | static int |
c3c55696 AN |
577 | bpf_object__init_prog(struct bpf_object *obj, struct bpf_program *prog, |
578 | const char *name, size_t sec_idx, const char *sec_name, | |
579 | size_t sec_off, void *insn_data, size_t insn_data_sz) | |
a5b8bd47 | 580 | { |
c1122392 AN |
581 | if (insn_data_sz == 0 || insn_data_sz % BPF_INSN_SZ || sec_off % BPF_INSN_SZ) { |
582 | pr_warn("sec '%s': corrupted program '%s', offset %zu, size %zu\n", | |
583 | sec_name, name, sec_off, insn_data_sz); | |
a5b8bd47 WN |
584 | return -EINVAL; |
585 | } | |
586 | ||
1ad9cbb8 | 587 | memset(prog, 0, sizeof(*prog)); |
c3c55696 AN |
588 | prog->obj = obj; |
589 | ||
c1122392 AN |
590 | prog->sec_idx = sec_idx; |
591 | prog->sec_insn_off = sec_off / BPF_INSN_SZ; | |
592 | prog->sec_insn_cnt = insn_data_sz / BPF_INSN_SZ; | |
593 | /* insns_cnt can later be increased by appending used subprograms */ | |
594 | prog->insns_cnt = prog->sec_insn_cnt; | |
a5b8bd47 | 595 | |
c1122392 AN |
596 | prog->type = BPF_PROG_TYPE_UNSPEC; |
597 | prog->load = true; | |
a5b8bd47 | 598 | |
c1122392 AN |
599 | prog->instances.fds = NULL; |
600 | prog->instances.nr = -1; | |
601 | ||
52109584 AN |
602 | prog->sec_name = strdup(sec_name); |
603 | if (!prog->sec_name) | |
c1122392 AN |
604 | goto errout; |
605 | ||
606 | prog->name = strdup(name); | |
607 | if (!prog->name) | |
a5b8bd47 | 608 | goto errout; |
a5b8bd47 | 609 | |
33a2c75c | 610 | prog->pin_name = __bpf_program__pin_name(prog); |
c1122392 | 611 | if (!prog->pin_name) |
33a2c75c | 612 | goto errout; |
33a2c75c | 613 | |
c1122392 AN |
614 | prog->insns = malloc(insn_data_sz); |
615 | if (!prog->insns) | |
a5b8bd47 | 616 | goto errout; |
c1122392 | 617 | memcpy(prog->insns, insn_data, insn_data_sz); |
a5b8bd47 WN |
618 | |
619 | return 0; | |
620 | errout: | |
c1122392 | 621 | pr_warn("sec '%s': failed to allocate memory for prog '%s'\n", sec_name, name); |
a5b8bd47 WN |
622 | bpf_program__exit(prog); |
623 | return -ENOMEM; | |
624 | } | |
625 | ||
626 | static int | |
c1122392 AN |
627 | bpf_object__add_programs(struct bpf_object *obj, Elf_Data *sec_data, |
628 | const char *sec_name, int sec_idx) | |
a5b8bd47 | 629 | { |
c1122392 AN |
630 | struct bpf_program *prog, *progs; |
631 | void *data = sec_data->d_buf; | |
632 | size_t sec_sz = sec_data->d_size, sec_off, prog_sz; | |
a5b8bd47 | 633 | int nr_progs, err; |
c1122392 AN |
634 | const char *name; |
635 | GElf_Sym sym; | |
a5b8bd47 WN |
636 | |
637 | progs = obj->programs; | |
638 | nr_progs = obj->nr_programs; | |
c1122392 | 639 | sec_off = 0; |
a5b8bd47 | 640 | |
c1122392 AN |
641 | while (sec_off < sec_sz) { |
642 | if (elf_sym_by_sec_off(obj, sec_idx, sec_off, STT_FUNC, &sym)) { | |
643 | pr_warn("sec '%s': failed to find program symbol at offset %zu\n", | |
644 | sec_name, sec_off); | |
645 | return -LIBBPF_ERRNO__FORMAT; | |
646 | } | |
88cda1c9 | 647 | |
c1122392 | 648 | prog_sz = sym.st_size; |
88cda1c9 | 649 | |
c1122392 AN |
650 | name = elf_sym_str(obj, sym.st_name); |
651 | if (!name) { | |
652 | pr_warn("sec '%s': failed to get symbol name for offset %zu\n", | |
653 | sec_name, sec_off); | |
654 | return -LIBBPF_ERRNO__FORMAT; | |
655 | } | |
88cda1c9 | 656 | |
c1122392 AN |
657 | if (sec_off + prog_sz > sec_sz) { |
658 | pr_warn("sec '%s': program at offset %zu crosses section boundary\n", | |
659 | sec_name, sec_off); | |
660 | return -LIBBPF_ERRNO__FORMAT; | |
661 | } | |
88cda1c9 | 662 | |
c3c55696 AN |
663 | pr_debug("sec '%s': found program '%s' at insn offset %zu (%zu bytes), code size %zu insns (%zu bytes)\n", |
664 | sec_name, name, sec_off / BPF_INSN_SZ, sec_off, prog_sz / BPF_INSN_SZ, prog_sz); | |
88cda1c9 | 665 | |
c3c55696 | 666 | progs = libbpf_reallocarray(progs, nr_progs + 1, sizeof(*progs)); |
c1122392 AN |
667 | if (!progs) { |
668 | /* | |
669 | * In this case the original obj->programs | |
670 | * is still valid, so don't need special treat for | |
671 | * bpf_close_object(). | |
672 | */ | |
673 | pr_warn("sec '%s': failed to alloc memory for new program '%s'\n", | |
674 | sec_name, name); | |
675 | return -ENOMEM; | |
88cda1c9 | 676 | } |
c1122392 | 677 | obj->programs = progs; |
88cda1c9 | 678 | |
c1122392 | 679 | prog = &progs[nr_progs]; |
9a94f277 | 680 | |
c3c55696 AN |
681 | err = bpf_object__init_prog(obj, prog, name, sec_idx, sec_name, |
682 | sec_off, data + sec_off, prog_sz); | |
c1122392 AN |
683 | if (err) |
684 | return err; | |
9a94f277 | 685 | |
c1122392 AN |
686 | nr_progs++; |
687 | obj->nr_programs = nr_progs; | |
688 | ||
689 | sec_off += prog_sz; | |
88cda1c9 MKL |
690 | } |
691 | ||
692 | return 0; | |
693 | } | |
694 | ||
5e61f270 AN |
695 | static __u32 get_kernel_version(void) |
696 | { | |
697 | __u32 major, minor, patch; | |
698 | struct utsname info; | |
699 | ||
700 | uname(&info); | |
701 | if (sscanf(info.release, "%u.%u.%u", &major, &minor, &patch) != 3) | |
702 | return 0; | |
703 | return KERNEL_VERSION(major, minor, patch); | |
704 | } | |
705 | ||
590a0088 MKL |
706 | static const struct btf_member * |
707 | find_member_by_offset(const struct btf_type *t, __u32 bit_offset) | |
708 | { | |
709 | struct btf_member *m; | |
710 | int i; | |
711 | ||
712 | for (i = 0, m = btf_members(t); i < btf_vlen(t); i++, m++) { | |
713 | if (btf_member_bit_offset(t, i) == bit_offset) | |
714 | return m; | |
715 | } | |
716 | ||
717 | return NULL; | |
718 | } | |
719 | ||
720 | static const struct btf_member * | |
721 | find_member_by_name(const struct btf *btf, const struct btf_type *t, | |
722 | const char *name) | |
723 | { | |
724 | struct btf_member *m; | |
725 | int i; | |
726 | ||
727 | for (i = 0, m = btf_members(t); i < btf_vlen(t); i++, m++) { | |
728 | if (!strcmp(btf__name_by_offset(btf, m->name_off), name)) | |
729 | return m; | |
730 | } | |
731 | ||
732 | return NULL; | |
733 | } | |
734 | ||
735 | #define STRUCT_OPS_VALUE_PREFIX "bpf_struct_ops_" | |
a6ed02ca KS |
736 | static int find_btf_by_prefix_kind(const struct btf *btf, const char *prefix, |
737 | const char *name, __u32 kind); | |
590a0088 MKL |
738 | |
739 | static int | |
740 | find_struct_ops_kern_types(const struct btf *btf, const char *tname, | |
741 | const struct btf_type **type, __u32 *type_id, | |
742 | const struct btf_type **vtype, __u32 *vtype_id, | |
743 | const struct btf_member **data_member) | |
744 | { | |
745 | const struct btf_type *kern_type, *kern_vtype; | |
746 | const struct btf_member *kern_data_member; | |
747 | __s32 kern_vtype_id, kern_type_id; | |
590a0088 MKL |
748 | __u32 i; |
749 | ||
750 | kern_type_id = btf__find_by_name_kind(btf, tname, BTF_KIND_STRUCT); | |
751 | if (kern_type_id < 0) { | |
752 | pr_warn("struct_ops init_kern: struct %s is not found in kernel BTF\n", | |
753 | tname); | |
754 | return kern_type_id; | |
755 | } | |
756 | kern_type = btf__type_by_id(btf, kern_type_id); | |
757 | ||
758 | /* Find the corresponding "map_value" type that will be used | |
759 | * in map_update(BPF_MAP_TYPE_STRUCT_OPS). For example, | |
760 | * find "struct bpf_struct_ops_tcp_congestion_ops" from the | |
761 | * btf_vmlinux. | |
762 | */ | |
a6ed02ca KS |
763 | kern_vtype_id = find_btf_by_prefix_kind(btf, STRUCT_OPS_VALUE_PREFIX, |
764 | tname, BTF_KIND_STRUCT); | |
590a0088 | 765 | if (kern_vtype_id < 0) { |
a6ed02ca KS |
766 | pr_warn("struct_ops init_kern: struct %s%s is not found in kernel BTF\n", |
767 | STRUCT_OPS_VALUE_PREFIX, tname); | |
590a0088 MKL |
768 | return kern_vtype_id; |
769 | } | |
770 | kern_vtype = btf__type_by_id(btf, kern_vtype_id); | |
771 | ||
772 | /* Find "struct tcp_congestion_ops" from | |
773 | * struct bpf_struct_ops_tcp_congestion_ops { | |
774 | * [ ... ] | |
775 | * struct tcp_congestion_ops data; | |
776 | * } | |
777 | */ | |
778 | kern_data_member = btf_members(kern_vtype); | |
779 | for (i = 0; i < btf_vlen(kern_vtype); i++, kern_data_member++) { | |
780 | if (kern_data_member->type == kern_type_id) | |
781 | break; | |
782 | } | |
783 | if (i == btf_vlen(kern_vtype)) { | |
a6ed02ca KS |
784 | pr_warn("struct_ops init_kern: struct %s data is not found in struct %s%s\n", |
785 | tname, STRUCT_OPS_VALUE_PREFIX, tname); | |
590a0088 MKL |
786 | return -EINVAL; |
787 | } | |
788 | ||
789 | *type = kern_type; | |
790 | *type_id = kern_type_id; | |
791 | *vtype = kern_vtype; | |
792 | *vtype_id = kern_vtype_id; | |
793 | *data_member = kern_data_member; | |
794 | ||
795 | return 0; | |
796 | } | |
797 | ||
798 | static bool bpf_map__is_struct_ops(const struct bpf_map *map) | |
799 | { | |
800 | return map->def.type == BPF_MAP_TYPE_STRUCT_OPS; | |
801 | } | |
802 | ||
803 | /* Init the map's fields that depend on kern_btf */ | |
804 | static int bpf_map__init_kern_struct_ops(struct bpf_map *map, | |
805 | const struct btf *btf, | |
806 | const struct btf *kern_btf) | |
807 | { | |
808 | const struct btf_member *member, *kern_member, *kern_data_member; | |
809 | const struct btf_type *type, *kern_type, *kern_vtype; | |
810 | __u32 i, kern_type_id, kern_vtype_id, kern_data_off; | |
811 | struct bpf_struct_ops *st_ops; | |
812 | void *data, *kern_data; | |
813 | const char *tname; | |
814 | int err; | |
815 | ||
816 | st_ops = map->st_ops; | |
817 | type = st_ops->type; | |
818 | tname = st_ops->tname; | |
819 | err = find_struct_ops_kern_types(kern_btf, tname, | |
820 | &kern_type, &kern_type_id, | |
821 | &kern_vtype, &kern_vtype_id, | |
822 | &kern_data_member); | |
823 | if (err) | |
824 | return err; | |
825 | ||
826 | pr_debug("struct_ops init_kern %s: type_id:%u kern_type_id:%u kern_vtype_id:%u\n", | |
827 | map->name, st_ops->type_id, kern_type_id, kern_vtype_id); | |
828 | ||
829 | map->def.value_size = kern_vtype->size; | |
830 | map->btf_vmlinux_value_type_id = kern_vtype_id; | |
831 | ||
832 | st_ops->kern_vdata = calloc(1, kern_vtype->size); | |
833 | if (!st_ops->kern_vdata) | |
834 | return -ENOMEM; | |
835 | ||
836 | data = st_ops->data; | |
837 | kern_data_off = kern_data_member->offset / 8; | |
838 | kern_data = st_ops->kern_vdata + kern_data_off; | |
839 | ||
840 | member = btf_members(type); | |
841 | for (i = 0; i < btf_vlen(type); i++, member++) { | |
842 | const struct btf_type *mtype, *kern_mtype; | |
843 | __u32 mtype_id, kern_mtype_id; | |
844 | void *mdata, *kern_mdata; | |
845 | __s64 msize, kern_msize; | |
846 | __u32 moff, kern_moff; | |
847 | __u32 kern_member_idx; | |
848 | const char *mname; | |
849 | ||
850 | mname = btf__name_by_offset(btf, member->name_off); | |
851 | kern_member = find_member_by_name(kern_btf, kern_type, mname); | |
852 | if (!kern_member) { | |
853 | pr_warn("struct_ops init_kern %s: Cannot find member %s in kernel BTF\n", | |
854 | map->name, mname); | |
855 | return -ENOTSUP; | |
856 | } | |
857 | ||
858 | kern_member_idx = kern_member - btf_members(kern_type); | |
859 | if (btf_member_bitfield_size(type, i) || | |
860 | btf_member_bitfield_size(kern_type, kern_member_idx)) { | |
861 | pr_warn("struct_ops init_kern %s: bitfield %s is not supported\n", | |
862 | map->name, mname); | |
863 | return -ENOTSUP; | |
864 | } | |
865 | ||
866 | moff = member->offset / 8; | |
867 | kern_moff = kern_member->offset / 8; | |
868 | ||
869 | mdata = data + moff; | |
870 | kern_mdata = kern_data + kern_moff; | |
871 | ||
872 | mtype = skip_mods_and_typedefs(btf, member->type, &mtype_id); | |
873 | kern_mtype = skip_mods_and_typedefs(kern_btf, kern_member->type, | |
874 | &kern_mtype_id); | |
875 | if (BTF_INFO_KIND(mtype->info) != | |
876 | BTF_INFO_KIND(kern_mtype->info)) { | |
877 | pr_warn("struct_ops init_kern %s: Unmatched member type %s %u != %u(kernel)\n", | |
878 | map->name, mname, BTF_INFO_KIND(mtype->info), | |
879 | BTF_INFO_KIND(kern_mtype->info)); | |
880 | return -ENOTSUP; | |
881 | } | |
882 | ||
883 | if (btf_is_ptr(mtype)) { | |
884 | struct bpf_program *prog; | |
885 | ||
886 | mtype = skip_mods_and_typedefs(btf, mtype->type, &mtype_id); | |
887 | kern_mtype = skip_mods_and_typedefs(kern_btf, | |
888 | kern_mtype->type, | |
889 | &kern_mtype_id); | |
890 | if (!btf_is_func_proto(mtype) || | |
891 | !btf_is_func_proto(kern_mtype)) { | |
892 | pr_warn("struct_ops init_kern %s: non func ptr %s is not supported\n", | |
893 | map->name, mname); | |
894 | return -ENOTSUP; | |
895 | } | |
896 | ||
897 | prog = st_ops->progs[i]; | |
898 | if (!prog) { | |
899 | pr_debug("struct_ops init_kern %s: func ptr %s is not set\n", | |
900 | map->name, mname); | |
901 | continue; | |
902 | } | |
903 | ||
904 | prog->attach_btf_id = kern_type_id; | |
905 | prog->expected_attach_type = kern_member_idx; | |
906 | ||
907 | st_ops->kern_func_off[i] = kern_data_off + kern_moff; | |
908 | ||
909 | pr_debug("struct_ops init_kern %s: func ptr %s is set to prog %s from data(+%u) to kern_data(+%u)\n", | |
910 | map->name, mname, prog->name, moff, | |
911 | kern_moff); | |
912 | ||
913 | continue; | |
914 | } | |
915 | ||
916 | msize = btf__resolve_size(btf, mtype_id); | |
917 | kern_msize = btf__resolve_size(kern_btf, kern_mtype_id); | |
918 | if (msize < 0 || kern_msize < 0 || msize != kern_msize) { | |
919 | pr_warn("struct_ops init_kern %s: Error in size of member %s: %zd != %zd(kernel)\n", | |
920 | map->name, mname, (ssize_t)msize, | |
921 | (ssize_t)kern_msize); | |
922 | return -ENOTSUP; | |
923 | } | |
924 | ||
925 | pr_debug("struct_ops init_kern %s: copy %s %u bytes from data(+%u) to kern_data(+%u)\n", | |
926 | map->name, mname, (unsigned int)msize, | |
927 | moff, kern_moff); | |
928 | memcpy(kern_mdata, mdata, msize); | |
929 | } | |
930 | ||
931 | return 0; | |
932 | } | |
933 | ||
934 | static int bpf_object__init_kern_struct_ops_maps(struct bpf_object *obj) | |
935 | { | |
590a0088 MKL |
936 | struct bpf_map *map; |
937 | size_t i; | |
938 | int err; | |
939 | ||
940 | for (i = 0; i < obj->nr_maps; i++) { | |
941 | map = &obj->maps[i]; | |
942 | ||
943 | if (!bpf_map__is_struct_ops(map)) | |
944 | continue; | |
945 | ||
a6ed02ca KS |
946 | err = bpf_map__init_kern_struct_ops(map, obj->btf, |
947 | obj->btf_vmlinux); | |
948 | if (err) | |
590a0088 | 949 | return err; |
590a0088 MKL |
950 | } |
951 | ||
590a0088 MKL |
952 | return 0; |
953 | } | |
954 | ||
955 | static int bpf_object__init_struct_ops_maps(struct bpf_object *obj) | |
956 | { | |
957 | const struct btf_type *type, *datasec; | |
958 | const struct btf_var_secinfo *vsi; | |
959 | struct bpf_struct_ops *st_ops; | |
960 | const char *tname, *var_name; | |
961 | __s32 type_id, datasec_id; | |
962 | const struct btf *btf; | |
963 | struct bpf_map *map; | |
964 | __u32 i; | |
965 | ||
966 | if (obj->efile.st_ops_shndx == -1) | |
967 | return 0; | |
968 | ||
969 | btf = obj->btf; | |
970 | datasec_id = btf__find_by_name_kind(btf, STRUCT_OPS_SEC, | |
971 | BTF_KIND_DATASEC); | |
972 | if (datasec_id < 0) { | |
973 | pr_warn("struct_ops init: DATASEC %s not found\n", | |
974 | STRUCT_OPS_SEC); | |
975 | return -EINVAL; | |
976 | } | |
977 | ||
978 | datasec = btf__type_by_id(btf, datasec_id); | |
979 | vsi = btf_var_secinfos(datasec); | |
980 | for (i = 0; i < btf_vlen(datasec); i++, vsi++) { | |
981 | type = btf__type_by_id(obj->btf, vsi->type); | |
982 | var_name = btf__name_by_offset(obj->btf, type->name_off); | |
983 | ||
984 | type_id = btf__resolve_type(obj->btf, vsi->type); | |
985 | if (type_id < 0) { | |
986 | pr_warn("struct_ops init: Cannot resolve var type_id %u in DATASEC %s\n", | |
987 | vsi->type, STRUCT_OPS_SEC); | |
988 | return -EINVAL; | |
989 | } | |
990 | ||
991 | type = btf__type_by_id(obj->btf, type_id); | |
992 | tname = btf__name_by_offset(obj->btf, type->name_off); | |
993 | if (!tname[0]) { | |
994 | pr_warn("struct_ops init: anonymous type is not supported\n"); | |
995 | return -ENOTSUP; | |
996 | } | |
997 | if (!btf_is_struct(type)) { | |
998 | pr_warn("struct_ops init: %s is not a struct\n", tname); | |
999 | return -EINVAL; | |
1000 | } | |
1001 | ||
1002 | map = bpf_object__add_map(obj); | |
1003 | if (IS_ERR(map)) | |
1004 | return PTR_ERR(map); | |
1005 | ||
1006 | map->sec_idx = obj->efile.st_ops_shndx; | |
1007 | map->sec_offset = vsi->offset; | |
1008 | map->name = strdup(var_name); | |
1009 | if (!map->name) | |
1010 | return -ENOMEM; | |
1011 | ||
1012 | map->def.type = BPF_MAP_TYPE_STRUCT_OPS; | |
1013 | map->def.key_size = sizeof(int); | |
1014 | map->def.value_size = type->size; | |
1015 | map->def.max_entries = 1; | |
1016 | ||
1017 | map->st_ops = calloc(1, sizeof(*map->st_ops)); | |
1018 | if (!map->st_ops) | |
1019 | return -ENOMEM; | |
1020 | st_ops = map->st_ops; | |
1021 | st_ops->data = malloc(type->size); | |
1022 | st_ops->progs = calloc(btf_vlen(type), sizeof(*st_ops->progs)); | |
1023 | st_ops->kern_func_off = malloc(btf_vlen(type) * | |
1024 | sizeof(*st_ops->kern_func_off)); | |
1025 | if (!st_ops->data || !st_ops->progs || !st_ops->kern_func_off) | |
1026 | return -ENOMEM; | |
1027 | ||
1028 | if (vsi->offset + type->size > obj->efile.st_ops_data->d_size) { | |
1029 | pr_warn("struct_ops init: var %s is beyond the end of DATASEC %s\n", | |
1030 | var_name, STRUCT_OPS_SEC); | |
1031 | return -EINVAL; | |
1032 | } | |
1033 | ||
1034 | memcpy(st_ops->data, | |
1035 | obj->efile.st_ops_data->d_buf + vsi->offset, | |
1036 | type->size); | |
1037 | st_ops->tname = tname; | |
1038 | st_ops->type = type; | |
1039 | st_ops->type_id = type_id; | |
1040 | ||
1041 | pr_debug("struct_ops init: struct %s(type_id=%u) %s found at offset %u\n", | |
1042 | tname, type_id, var_name, vsi->offset); | |
1043 | } | |
1044 | ||
1045 | return 0; | |
1046 | } | |
1047 | ||
6c956392 | 1048 | static struct bpf_object *bpf_object__new(const char *path, |
5e61f270 | 1049 | const void *obj_buf, |
2ce8450e AN |
1050 | size_t obj_buf_sz, |
1051 | const char *obj_name) | |
1a5e3fb1 WN |
1052 | { |
1053 | struct bpf_object *obj; | |
d859900c | 1054 | char *end; |
1a5e3fb1 WN |
1055 | |
1056 | obj = calloc(1, sizeof(struct bpf_object) + strlen(path) + 1); | |
1057 | if (!obj) { | |
be18010e | 1058 | pr_warn("alloc memory failed for %s\n", path); |
6371ca3b | 1059 | return ERR_PTR(-ENOMEM); |
1a5e3fb1 WN |
1060 | } |
1061 | ||
1062 | strcpy(obj->path, path); | |
2ce8450e AN |
1063 | if (obj_name) { |
1064 | strncpy(obj->name, obj_name, sizeof(obj->name) - 1); | |
1065 | obj->name[sizeof(obj->name) - 1] = 0; | |
1066 | } else { | |
1067 | /* Using basename() GNU version which doesn't modify arg. */ | |
1068 | strncpy(obj->name, basename((void *)path), | |
1069 | sizeof(obj->name) - 1); | |
1070 | end = strchr(obj->name, '.'); | |
1071 | if (end) | |
1072 | *end = 0; | |
1073 | } | |
6c956392 | 1074 | |
d859900c | 1075 | obj->efile.fd = -1; |
6c956392 | 1076 | /* |
76e1022b | 1077 | * Caller of this function should also call |
6c956392 WN |
1078 | * bpf_object__elf_finish() after data collection to return |
1079 | * obj_buf to user. If not, we should duplicate the buffer to | |
1080 | * avoid user freeing them before elf finish. | |
1081 | */ | |
1082 | obj->efile.obj_buf = obj_buf; | |
1083 | obj->efile.obj_buf_sz = obj_buf_sz; | |
666810e8 | 1084 | obj->efile.maps_shndx = -1; |
abd29c93 | 1085 | obj->efile.btf_maps_shndx = -1; |
d859900c DB |
1086 | obj->efile.data_shndx = -1; |
1087 | obj->efile.rodata_shndx = -1; | |
1088 | obj->efile.bss_shndx = -1; | |
590a0088 | 1089 | obj->efile.st_ops_shndx = -1; |
81bfdd08 | 1090 | obj->kconfig_map_idx = -1; |
5d23328d | 1091 | obj->rodata_map_idx = -1; |
6c956392 | 1092 | |
5e61f270 | 1093 | obj->kern_version = get_kernel_version(); |
52d3352e | 1094 | obj->loaded = false; |
9a208eff WN |
1095 | |
1096 | INIT_LIST_HEAD(&obj->list); | |
1097 | list_add(&obj->list, &bpf_objects_list); | |
1a5e3fb1 WN |
1098 | return obj; |
1099 | } | |
1100 | ||
1101 | static void bpf_object__elf_finish(struct bpf_object *obj) | |
1102 | { | |
1103 | if (!obj_elf_valid(obj)) | |
1104 | return; | |
1105 | ||
1106 | if (obj->efile.elf) { | |
1107 | elf_end(obj->efile.elf); | |
1108 | obj->efile.elf = NULL; | |
1109 | } | |
bec7d68c | 1110 | obj->efile.symbols = NULL; |
d859900c DB |
1111 | obj->efile.data = NULL; |
1112 | obj->efile.rodata = NULL; | |
1113 | obj->efile.bss = NULL; | |
590a0088 | 1114 | obj->efile.st_ops_data = NULL; |
b62f06e8 | 1115 | |
1f8e2bcb AN |
1116 | zfree(&obj->efile.reloc_sects); |
1117 | obj->efile.nr_reloc_sects = 0; | |
1a5e3fb1 | 1118 | zclose(obj->efile.fd); |
6c956392 WN |
1119 | obj->efile.obj_buf = NULL; |
1120 | obj->efile.obj_buf_sz = 0; | |
1a5e3fb1 WN |
1121 | } |
1122 | ||
22dd1ac9 AN |
1123 | /* if libelf is old and doesn't support mmap(), fall back to read() */ |
1124 | #ifndef ELF_C_READ_MMAP | |
1125 | #define ELF_C_READ_MMAP ELF_C_READ | |
1126 | #endif | |
1127 | ||
1a5e3fb1 WN |
1128 | static int bpf_object__elf_init(struct bpf_object *obj) |
1129 | { | |
1130 | int err = 0; | |
1131 | GElf_Ehdr *ep; | |
1132 | ||
1133 | if (obj_elf_valid(obj)) { | |
88a82120 | 1134 | pr_warn("elf: init internal error\n"); |
6371ca3b | 1135 | return -LIBBPF_ERRNO__LIBELF; |
1a5e3fb1 WN |
1136 | } |
1137 | ||
6c956392 WN |
1138 | if (obj->efile.obj_buf_sz > 0) { |
1139 | /* | |
1140 | * obj_buf should have been validated by | |
1141 | * bpf_object__open_buffer(). | |
1142 | */ | |
5e61f270 | 1143 | obj->efile.elf = elf_memory((char *)obj->efile.obj_buf, |
6c956392 WN |
1144 | obj->efile.obj_buf_sz); |
1145 | } else { | |
1146 | obj->efile.fd = open(obj->path, O_RDONLY); | |
1147 | if (obj->efile.fd < 0) { | |
be5c5d4e | 1148 | char errmsg[STRERR_BUFSIZE], *cp; |
1ce6a9fc | 1149 | |
be5c5d4e AN |
1150 | err = -errno; |
1151 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
88a82120 | 1152 | pr_warn("elf: failed to open %s: %s\n", obj->path, cp); |
be5c5d4e | 1153 | return err; |
6c956392 WN |
1154 | } |
1155 | ||
22dd1ac9 | 1156 | obj->efile.elf = elf_begin(obj->efile.fd, ELF_C_READ_MMAP, NULL); |
1a5e3fb1 WN |
1157 | } |
1158 | ||
1a5e3fb1 | 1159 | if (!obj->efile.elf) { |
88a82120 | 1160 | pr_warn("elf: failed to open %s as ELF file: %s\n", obj->path, elf_errmsg(-1)); |
6371ca3b | 1161 | err = -LIBBPF_ERRNO__LIBELF; |
1a5e3fb1 WN |
1162 | goto errout; |
1163 | } | |
1164 | ||
1165 | if (!gelf_getehdr(obj->efile.elf, &obj->efile.ehdr)) { | |
88a82120 | 1166 | pr_warn("elf: failed to get ELF header from %s: %s\n", obj->path, elf_errmsg(-1)); |
6371ca3b | 1167 | err = -LIBBPF_ERRNO__FORMAT; |
1a5e3fb1 WN |
1168 | goto errout; |
1169 | } | |
1170 | ep = &obj->efile.ehdr; | |
1171 | ||
88a82120 AN |
1172 | if (elf_getshdrstrndx(obj->efile.elf, &obj->efile.shstrndx)) { |
1173 | pr_warn("elf: failed to get section names section index for %s: %s\n", | |
1174 | obj->path, elf_errmsg(-1)); | |
1175 | err = -LIBBPF_ERRNO__FORMAT; | |
1176 | goto errout; | |
1177 | } | |
1178 | ||
1179 | /* Elf is corrupted/truncated, avoid calling elf_strptr. */ | |
1180 | if (!elf_rawdata(elf_getscn(obj->efile.elf, obj->efile.shstrndx), NULL)) { | |
1181 | pr_warn("elf: failed to get section names strings from %s: %s\n", | |
1182 | obj->path, elf_errmsg(-1)); | |
1183 | return -LIBBPF_ERRNO__FORMAT; | |
1184 | } | |
1185 | ||
9b16137a | 1186 | /* Old LLVM set e_machine to EM_NONE */ |
76e1022b AN |
1187 | if (ep->e_type != ET_REL || |
1188 | (ep->e_machine && ep->e_machine != EM_BPF)) { | |
88a82120 | 1189 | pr_warn("elf: %s is not a valid eBPF object file\n", obj->path); |
6371ca3b | 1190 | err = -LIBBPF_ERRNO__FORMAT; |
1a5e3fb1 WN |
1191 | goto errout; |
1192 | } | |
1193 | ||
1194 | return 0; | |
1195 | errout: | |
1196 | bpf_object__elf_finish(obj); | |
1197 | return err; | |
1198 | } | |
1199 | ||
12ef5634 | 1200 | static int bpf_object__check_endianness(struct bpf_object *obj) |
cc4228d5 | 1201 | { |
cdb2f920 | 1202 | #if __BYTE_ORDER == __LITTLE_ENDIAN |
12ef5634 AN |
1203 | if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2LSB) |
1204 | return 0; | |
cdb2f920 | 1205 | #elif __BYTE_ORDER == __BIG_ENDIAN |
12ef5634 AN |
1206 | if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2MSB) |
1207 | return 0; | |
1208 | #else | |
1209 | # error "Unrecognized __BYTE_ORDER__" | |
1210 | #endif | |
88a82120 | 1211 | pr_warn("elf: endianness mismatch in %s.\n", obj->path); |
6371ca3b | 1212 | return -LIBBPF_ERRNO__ENDIAN; |
cc4228d5 WN |
1213 | } |
1214 | ||
cb1e5e96 | 1215 | static int |
399dc65e | 1216 | bpf_object__init_license(struct bpf_object *obj, void *data, size_t size) |
cb1e5e96 | 1217 | { |
399dc65e | 1218 | memcpy(obj->license, data, min(size, sizeof(obj->license) - 1)); |
cb1e5e96 WN |
1219 | pr_debug("license of %s is %s\n", obj->path, obj->license); |
1220 | return 0; | |
1221 | } | |
1222 | ||
54b8625c JF |
1223 | static int |
1224 | bpf_object__init_kversion(struct bpf_object *obj, void *data, size_t size) | |
1225 | { | |
1226 | __u32 kver; | |
1227 | ||
1228 | if (size != sizeof(kver)) { | |
be18010e | 1229 | pr_warn("invalid kver section in %s\n", obj->path); |
54b8625c JF |
1230 | return -LIBBPF_ERRNO__FORMAT; |
1231 | } | |
1232 | memcpy(&kver, data, sizeof(kver)); | |
1233 | obj->kern_version = kver; | |
1234 | pr_debug("kernel version of %s is %x\n", obj->path, obj->kern_version); | |
1235 | return 0; | |
1236 | } | |
1237 | ||
addb9fc9 NS |
1238 | static bool bpf_map_type__is_map_in_map(enum bpf_map_type type) |
1239 | { | |
1240 | if (type == BPF_MAP_TYPE_ARRAY_OF_MAPS || | |
1241 | type == BPF_MAP_TYPE_HASH_OF_MAPS) | |
1242 | return true; | |
1243 | return false; | |
1244 | } | |
1245 | ||
1713d68b DB |
1246 | int bpf_object__section_size(const struct bpf_object *obj, const char *name, |
1247 | __u32 *size) | |
1248 | { | |
1249 | int ret = -ENOENT; | |
1713d68b DB |
1250 | |
1251 | *size = 0; | |
1252 | if (!name) { | |
1253 | return -EINVAL; | |
ac9d1389 | 1254 | } else if (!strcmp(name, DATA_SEC)) { |
1713d68b DB |
1255 | if (obj->efile.data) |
1256 | *size = obj->efile.data->d_size; | |
ac9d1389 | 1257 | } else if (!strcmp(name, BSS_SEC)) { |
1713d68b DB |
1258 | if (obj->efile.bss) |
1259 | *size = obj->efile.bss->d_size; | |
ac9d1389 | 1260 | } else if (!strcmp(name, RODATA_SEC)) { |
1713d68b DB |
1261 | if (obj->efile.rodata) |
1262 | *size = obj->efile.rodata->d_size; | |
590a0088 MKL |
1263 | } else if (!strcmp(name, STRUCT_OPS_SEC)) { |
1264 | if (obj->efile.st_ops_data) | |
1265 | *size = obj->efile.st_ops_data->d_size; | |
1713d68b | 1266 | } else { |
88a82120 AN |
1267 | Elf_Scn *scn = elf_sec_by_name(obj, name); |
1268 | Elf_Data *data = elf_sec_data(obj, scn); | |
1269 | ||
1270 | if (data) { | |
1271 | ret = 0; /* found it */ | |
1272 | *size = data->d_size; | |
1273 | } | |
1713d68b DB |
1274 | } |
1275 | ||
1276 | return *size ? 0 : ret; | |
1277 | } | |
1278 | ||
1279 | int bpf_object__variable_offset(const struct bpf_object *obj, const char *name, | |
1280 | __u32 *off) | |
1281 | { | |
1282 | Elf_Data *symbols = obj->efile.symbols; | |
1283 | const char *sname; | |
1284 | size_t si; | |
1285 | ||
1286 | if (!name || !off) | |
1287 | return -EINVAL; | |
1288 | ||
1289 | for (si = 0; si < symbols->d_size / sizeof(GElf_Sym); si++) { | |
1290 | GElf_Sym sym; | |
1291 | ||
1292 | if (!gelf_getsym(symbols, si, &sym)) | |
1293 | continue; | |
1294 | if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL || | |
1295 | GELF_ST_TYPE(sym.st_info) != STT_OBJECT) | |
1296 | continue; | |
1297 | ||
88a82120 | 1298 | sname = elf_sym_str(obj, sym.st_name); |
1713d68b | 1299 | if (!sname) { |
be18010e KW |
1300 | pr_warn("failed to get sym name string for var %s\n", |
1301 | name); | |
1713d68b DB |
1302 | return -EIO; |
1303 | } | |
1304 | if (strcmp(name, sname) == 0) { | |
1305 | *off = sym.st_value; | |
1306 | return 0; | |
1307 | } | |
1308 | } | |
1309 | ||
1310 | return -ENOENT; | |
1311 | } | |
1312 | ||
bf829271 | 1313 | static struct bpf_map *bpf_object__add_map(struct bpf_object *obj) |
d859900c | 1314 | { |
bf829271 AN |
1315 | struct bpf_map *new_maps; |
1316 | size_t new_cap; | |
1317 | int i; | |
1318 | ||
1319 | if (obj->nr_maps < obj->maps_cap) | |
1320 | return &obj->maps[obj->nr_maps++]; | |
1321 | ||
95064979 | 1322 | new_cap = max((size_t)4, obj->maps_cap * 3 / 2); |
029258d7 | 1323 | new_maps = libbpf_reallocarray(obj->maps, new_cap, sizeof(*obj->maps)); |
bf829271 | 1324 | if (!new_maps) { |
be18010e | 1325 | pr_warn("alloc maps for object failed\n"); |
bf829271 AN |
1326 | return ERR_PTR(-ENOMEM); |
1327 | } | |
1328 | ||
1329 | obj->maps_cap = new_cap; | |
1330 | obj->maps = new_maps; | |
1331 | ||
1332 | /* zero out new maps */ | |
1333 | memset(obj->maps + obj->nr_maps, 0, | |
1334 | (obj->maps_cap - obj->nr_maps) * sizeof(*obj->maps)); | |
1335 | /* | |
1336 | * fill all fd with -1 so won't close incorrect fd (fd=0 is stdin) | |
1337 | * when failure (zclose won't close negative fd)). | |
1338 | */ | |
1339 | for (i = obj->nr_maps; i < obj->maps_cap; i++) { | |
1340 | obj->maps[i].fd = -1; | |
1341 | obj->maps[i].inner_map_fd = -1; | |
1342 | } | |
1343 | ||
1344 | return &obj->maps[obj->nr_maps++]; | |
d859900c DB |
1345 | } |
1346 | ||
eba9c5f4 AN |
1347 | static size_t bpf_map_mmap_sz(const struct bpf_map *map) |
1348 | { | |
1349 | long page_sz = sysconf(_SC_PAGE_SIZE); | |
1350 | size_t map_sz; | |
1351 | ||
c701917e | 1352 | map_sz = (size_t)roundup(map->def.value_size, 8) * map->def.max_entries; |
eba9c5f4 AN |
1353 | map_sz = roundup(map_sz, page_sz); |
1354 | return map_sz; | |
1355 | } | |
1356 | ||
81bfdd08 AN |
1357 | static char *internal_map_name(struct bpf_object *obj, |
1358 | enum libbpf_map_type type) | |
1359 | { | |
113e6b7e | 1360 | char map_name[BPF_OBJ_NAME_LEN], *p; |
81bfdd08 AN |
1361 | const char *sfx = libbpf_type_to_btf_name[type]; |
1362 | int sfx_len = max((size_t)7, strlen(sfx)); | |
1363 | int pfx_len = min((size_t)BPF_OBJ_NAME_LEN - sfx_len - 1, | |
1364 | strlen(obj->name)); | |
1365 | ||
1366 | snprintf(map_name, sizeof(map_name), "%.*s%.*s", pfx_len, obj->name, | |
1367 | sfx_len, libbpf_type_to_btf_name[type]); | |
1368 | ||
113e6b7e THJ |
1369 | /* sanitise map name to characters allowed by kernel */ |
1370 | for (p = map_name; *p && p < map_name + sizeof(map_name); p++) | |
1371 | if (!isalnum(*p) && *p != '_' && *p != '.') | |
1372 | *p = '_'; | |
1373 | ||
81bfdd08 AN |
1374 | return strdup(map_name); |
1375 | } | |
1376 | ||
d859900c | 1377 | static int |
bf829271 | 1378 | bpf_object__init_internal_map(struct bpf_object *obj, enum libbpf_map_type type, |
eba9c5f4 | 1379 | int sec_idx, void *data, size_t data_sz) |
d859900c | 1380 | { |
bf829271 AN |
1381 | struct bpf_map_def *def; |
1382 | struct bpf_map *map; | |
eba9c5f4 | 1383 | int err; |
bf829271 AN |
1384 | |
1385 | map = bpf_object__add_map(obj); | |
1386 | if (IS_ERR(map)) | |
1387 | return PTR_ERR(map); | |
d859900c DB |
1388 | |
1389 | map->libbpf_type = type; | |
db48814b AN |
1390 | map->sec_idx = sec_idx; |
1391 | map->sec_offset = 0; | |
81bfdd08 | 1392 | map->name = internal_map_name(obj, type); |
d859900c | 1393 | if (!map->name) { |
be18010e | 1394 | pr_warn("failed to alloc map name\n"); |
d859900c DB |
1395 | return -ENOMEM; |
1396 | } | |
1397 | ||
bf829271 | 1398 | def = &map->def; |
d859900c DB |
1399 | def->type = BPF_MAP_TYPE_ARRAY; |
1400 | def->key_size = sizeof(int); | |
eba9c5f4 | 1401 | def->value_size = data_sz; |
d859900c | 1402 | def->max_entries = 1; |
81bfdd08 | 1403 | def->map_flags = type == LIBBPF_MAP_RODATA || type == LIBBPF_MAP_KCONFIG |
166750bc | 1404 | ? BPF_F_RDONLY_PROG : 0; |
0d13bfce | 1405 | def->map_flags |= BPF_F_MMAPABLE; |
7fe74b43 AN |
1406 | |
1407 | pr_debug("map '%s' (global data): at sec_idx %d, offset %zu, flags %x.\n", | |
81bfdd08 | 1408 | map->name, map->sec_idx, map->sec_offset, def->map_flags); |
7fe74b43 | 1409 | |
eba9c5f4 AN |
1410 | map->mmaped = mmap(NULL, bpf_map_mmap_sz(map), PROT_READ | PROT_WRITE, |
1411 | MAP_SHARED | MAP_ANONYMOUS, -1, 0); | |
1412 | if (map->mmaped == MAP_FAILED) { | |
1413 | err = -errno; | |
1414 | map->mmaped = NULL; | |
1415 | pr_warn("failed to alloc map '%s' content buffer: %d\n", | |
1416 | map->name, err); | |
1417 | zfree(&map->name); | |
1418 | return err; | |
d859900c DB |
1419 | } |
1420 | ||
166750bc | 1421 | if (data) |
eba9c5f4 AN |
1422 | memcpy(map->mmaped, data, data_sz); |
1423 | ||
e1d1dc46 | 1424 | pr_debug("map %td is \"%s\"\n", map - obj->maps, map->name); |
d859900c DB |
1425 | return 0; |
1426 | } | |
1427 | ||
bf829271 AN |
1428 | static int bpf_object__init_global_data_maps(struct bpf_object *obj) |
1429 | { | |
1430 | int err; | |
1431 | ||
bf829271 AN |
1432 | /* |
1433 | * Populate obj->maps with libbpf internal maps. | |
1434 | */ | |
1435 | if (obj->efile.data_shndx >= 0) { | |
1436 | err = bpf_object__init_internal_map(obj, LIBBPF_MAP_DATA, | |
db48814b | 1437 | obj->efile.data_shndx, |
eba9c5f4 AN |
1438 | obj->efile.data->d_buf, |
1439 | obj->efile.data->d_size); | |
bf829271 AN |
1440 | if (err) |
1441 | return err; | |
1442 | } | |
1443 | if (obj->efile.rodata_shndx >= 0) { | |
1444 | err = bpf_object__init_internal_map(obj, LIBBPF_MAP_RODATA, | |
db48814b | 1445 | obj->efile.rodata_shndx, |
eba9c5f4 AN |
1446 | obj->efile.rodata->d_buf, |
1447 | obj->efile.rodata->d_size); | |
bf829271 AN |
1448 | if (err) |
1449 | return err; | |
5d23328d YZ |
1450 | |
1451 | obj->rodata_map_idx = obj->nr_maps - 1; | |
bf829271 AN |
1452 | } |
1453 | if (obj->efile.bss_shndx >= 0) { | |
1454 | err = bpf_object__init_internal_map(obj, LIBBPF_MAP_BSS, | |
db48814b | 1455 | obj->efile.bss_shndx, |
eba9c5f4 AN |
1456 | NULL, |
1457 | obj->efile.bss->d_size); | |
bf829271 AN |
1458 | if (err) |
1459 | return err; | |
1460 | } | |
1461 | return 0; | |
1462 | } | |
1463 | ||
166750bc AN |
1464 | |
1465 | static struct extern_desc *find_extern_by_name(const struct bpf_object *obj, | |
1466 | const void *name) | |
1467 | { | |
1468 | int i; | |
1469 | ||
1470 | for (i = 0; i < obj->nr_extern; i++) { | |
1471 | if (strcmp(obj->externs[i].name, name) == 0) | |
1472 | return &obj->externs[i]; | |
1473 | } | |
1474 | return NULL; | |
1475 | } | |
1476 | ||
2e33efe3 AN |
1477 | static int set_kcfg_value_tri(struct extern_desc *ext, void *ext_val, |
1478 | char value) | |
166750bc | 1479 | { |
2e33efe3 AN |
1480 | switch (ext->kcfg.type) { |
1481 | case KCFG_BOOL: | |
166750bc | 1482 | if (value == 'm') { |
2e33efe3 | 1483 | pr_warn("extern (kcfg) %s=%c should be tristate or char\n", |
166750bc AN |
1484 | ext->name, value); |
1485 | return -EINVAL; | |
1486 | } | |
1487 | *(bool *)ext_val = value == 'y' ? true : false; | |
1488 | break; | |
2e33efe3 | 1489 | case KCFG_TRISTATE: |
166750bc AN |
1490 | if (value == 'y') |
1491 | *(enum libbpf_tristate *)ext_val = TRI_YES; | |
1492 | else if (value == 'm') | |
1493 | *(enum libbpf_tristate *)ext_val = TRI_MODULE; | |
1494 | else /* value == 'n' */ | |
1495 | *(enum libbpf_tristate *)ext_val = TRI_NO; | |
1496 | break; | |
2e33efe3 | 1497 | case KCFG_CHAR: |
166750bc AN |
1498 | *(char *)ext_val = value; |
1499 | break; | |
2e33efe3 AN |
1500 | case KCFG_UNKNOWN: |
1501 | case KCFG_INT: | |
1502 | case KCFG_CHAR_ARR: | |
166750bc | 1503 | default: |
2e33efe3 | 1504 | pr_warn("extern (kcfg) %s=%c should be bool, tristate, or char\n", |
166750bc AN |
1505 | ext->name, value); |
1506 | return -EINVAL; | |
1507 | } | |
1508 | ext->is_set = true; | |
1509 | return 0; | |
1510 | } | |
1511 | ||
2e33efe3 AN |
1512 | static int set_kcfg_value_str(struct extern_desc *ext, char *ext_val, |
1513 | const char *value) | |
166750bc AN |
1514 | { |
1515 | size_t len; | |
1516 | ||
2e33efe3 AN |
1517 | if (ext->kcfg.type != KCFG_CHAR_ARR) { |
1518 | pr_warn("extern (kcfg) %s=%s should be char array\n", ext->name, value); | |
166750bc AN |
1519 | return -EINVAL; |
1520 | } | |
1521 | ||
1522 | len = strlen(value); | |
1523 | if (value[len - 1] != '"') { | |
2e33efe3 | 1524 | pr_warn("extern (kcfg) '%s': invalid string config '%s'\n", |
166750bc AN |
1525 | ext->name, value); |
1526 | return -EINVAL; | |
1527 | } | |
1528 | ||
1529 | /* strip quotes */ | |
1530 | len -= 2; | |
2e33efe3 AN |
1531 | if (len >= ext->kcfg.sz) { |
1532 | pr_warn("extern (kcfg) '%s': long string config %s of (%zu bytes) truncated to %d bytes\n", | |
1533 | ext->name, value, len, ext->kcfg.sz - 1); | |
1534 | len = ext->kcfg.sz - 1; | |
166750bc AN |
1535 | } |
1536 | memcpy(ext_val, value + 1, len); | |
1537 | ext_val[len] = '\0'; | |
1538 | ext->is_set = true; | |
1539 | return 0; | |
1540 | } | |
1541 | ||
1542 | static int parse_u64(const char *value, __u64 *res) | |
1543 | { | |
1544 | char *value_end; | |
1545 | int err; | |
1546 | ||
1547 | errno = 0; | |
1548 | *res = strtoull(value, &value_end, 0); | |
1549 | if (errno) { | |
1550 | err = -errno; | |
1551 | pr_warn("failed to parse '%s' as integer: %d\n", value, err); | |
1552 | return err; | |
1553 | } | |
1554 | if (*value_end) { | |
1555 | pr_warn("failed to parse '%s' as integer completely\n", value); | |
1556 | return -EINVAL; | |
1557 | } | |
1558 | return 0; | |
1559 | } | |
1560 | ||
2e33efe3 | 1561 | static bool is_kcfg_value_in_range(const struct extern_desc *ext, __u64 v) |
166750bc | 1562 | { |
2e33efe3 | 1563 | int bit_sz = ext->kcfg.sz * 8; |
166750bc | 1564 | |
2e33efe3 | 1565 | if (ext->kcfg.sz == 8) |
166750bc AN |
1566 | return true; |
1567 | ||
1568 | /* Validate that value stored in u64 fits in integer of `ext->sz` | |
1569 | * bytes size without any loss of information. If the target integer | |
1570 | * is signed, we rely on the following limits of integer type of | |
1571 | * Y bits and subsequent transformation: | |
1572 | * | |
1573 | * -2^(Y-1) <= X <= 2^(Y-1) - 1 | |
1574 | * 0 <= X + 2^(Y-1) <= 2^Y - 1 | |
1575 | * 0 <= X + 2^(Y-1) < 2^Y | |
1576 | * | |
1577 | * For unsigned target integer, check that all the (64 - Y) bits are | |
1578 | * zero. | |
1579 | */ | |
2e33efe3 | 1580 | if (ext->kcfg.is_signed) |
166750bc AN |
1581 | return v + (1ULL << (bit_sz - 1)) < (1ULL << bit_sz); |
1582 | else | |
1583 | return (v >> bit_sz) == 0; | |
1584 | } | |
1585 | ||
2e33efe3 AN |
1586 | static int set_kcfg_value_num(struct extern_desc *ext, void *ext_val, |
1587 | __u64 value) | |
166750bc | 1588 | { |
2e33efe3 AN |
1589 | if (ext->kcfg.type != KCFG_INT && ext->kcfg.type != KCFG_CHAR) { |
1590 | pr_warn("extern (kcfg) %s=%llu should be integer\n", | |
7745ff98 | 1591 | ext->name, (unsigned long long)value); |
166750bc AN |
1592 | return -EINVAL; |
1593 | } | |
2e33efe3 AN |
1594 | if (!is_kcfg_value_in_range(ext, value)) { |
1595 | pr_warn("extern (kcfg) %s=%llu value doesn't fit in %d bytes\n", | |
1596 | ext->name, (unsigned long long)value, ext->kcfg.sz); | |
166750bc AN |
1597 | return -ERANGE; |
1598 | } | |
2e33efe3 | 1599 | switch (ext->kcfg.sz) { |
166750bc AN |
1600 | case 1: *(__u8 *)ext_val = value; break; |
1601 | case 2: *(__u16 *)ext_val = value; break; | |
1602 | case 4: *(__u32 *)ext_val = value; break; | |
1603 | case 8: *(__u64 *)ext_val = value; break; | |
1604 | default: | |
1605 | return -EINVAL; | |
1606 | } | |
1607 | ext->is_set = true; | |
1608 | return 0; | |
1609 | } | |
1610 | ||
8601fd42 AN |
1611 | static int bpf_object__process_kconfig_line(struct bpf_object *obj, |
1612 | char *buf, void *data) | |
166750bc | 1613 | { |
166750bc | 1614 | struct extern_desc *ext; |
8601fd42 | 1615 | char *sep, *value; |
166750bc AN |
1616 | int len, err = 0; |
1617 | void *ext_val; | |
1618 | __u64 num; | |
166750bc | 1619 | |
8601fd42 AN |
1620 | if (strncmp(buf, "CONFIG_", 7)) |
1621 | return 0; | |
166750bc | 1622 | |
8601fd42 AN |
1623 | sep = strchr(buf, '='); |
1624 | if (!sep) { | |
1625 | pr_warn("failed to parse '%s': no separator\n", buf); | |
1626 | return -EINVAL; | |
1627 | } | |
1628 | ||
1629 | /* Trim ending '\n' */ | |
1630 | len = strlen(buf); | |
1631 | if (buf[len - 1] == '\n') | |
1632 | buf[len - 1] = '\0'; | |
1633 | /* Split on '=' and ensure that a value is present. */ | |
1634 | *sep = '\0'; | |
1635 | if (!sep[1]) { | |
1636 | *sep = '='; | |
1637 | pr_warn("failed to parse '%s': no value\n", buf); | |
1638 | return -EINVAL; | |
1639 | } | |
1640 | ||
1641 | ext = find_extern_by_name(obj, buf); | |
1642 | if (!ext || ext->is_set) | |
1643 | return 0; | |
1644 | ||
2e33efe3 | 1645 | ext_val = data + ext->kcfg.data_off; |
8601fd42 AN |
1646 | value = sep + 1; |
1647 | ||
1648 | switch (*value) { | |
1649 | case 'y': case 'n': case 'm': | |
2e33efe3 | 1650 | err = set_kcfg_value_tri(ext, ext_val, *value); |
8601fd42 AN |
1651 | break; |
1652 | case '"': | |
2e33efe3 | 1653 | err = set_kcfg_value_str(ext, ext_val, value); |
8601fd42 AN |
1654 | break; |
1655 | default: | |
1656 | /* assume integer */ | |
1657 | err = parse_u64(value, &num); | |
1658 | if (err) { | |
2e33efe3 | 1659 | pr_warn("extern (kcfg) %s=%s should be integer\n", |
8601fd42 AN |
1660 | ext->name, value); |
1661 | return err; | |
1662 | } | |
2e33efe3 | 1663 | err = set_kcfg_value_num(ext, ext_val, num); |
8601fd42 | 1664 | break; |
166750bc | 1665 | } |
8601fd42 AN |
1666 | if (err) |
1667 | return err; | |
2e33efe3 | 1668 | pr_debug("extern (kcfg) %s=%s\n", ext->name, value); |
8601fd42 AN |
1669 | return 0; |
1670 | } | |
1671 | ||
1672 | static int bpf_object__read_kconfig_file(struct bpf_object *obj, void *data) | |
1673 | { | |
1674 | char buf[PATH_MAX]; | |
1675 | struct utsname uts; | |
1676 | int len, err = 0; | |
1677 | gzFile file; | |
1678 | ||
1679 | uname(&uts); | |
1680 | len = snprintf(buf, PATH_MAX, "/boot/config-%s", uts.release); | |
1681 | if (len < 0) | |
1682 | return -EINVAL; | |
1683 | else if (len >= PATH_MAX) | |
1684 | return -ENAMETOOLONG; | |
1685 | ||
1686 | /* gzopen also accepts uncompressed files. */ | |
1687 | file = gzopen(buf, "r"); | |
1688 | if (!file) | |
1689 | file = gzopen("/proc/config.gz", "r"); | |
1690 | ||
166750bc | 1691 | if (!file) { |
8601fd42 | 1692 | pr_warn("failed to open system Kconfig\n"); |
166750bc AN |
1693 | return -ENOENT; |
1694 | } | |
1695 | ||
1696 | while (gzgets(file, buf, sizeof(buf))) { | |
8601fd42 AN |
1697 | err = bpf_object__process_kconfig_line(obj, buf, data); |
1698 | if (err) { | |
1699 | pr_warn("error parsing system Kconfig line '%s': %d\n", | |
1700 | buf, err); | |
166750bc AN |
1701 | goto out; |
1702 | } | |
8601fd42 | 1703 | } |
166750bc | 1704 | |
8601fd42 AN |
1705 | out: |
1706 | gzclose(file); | |
1707 | return err; | |
1708 | } | |
166750bc | 1709 | |
8601fd42 AN |
1710 | static int bpf_object__read_kconfig_mem(struct bpf_object *obj, |
1711 | const char *config, void *data) | |
1712 | { | |
1713 | char buf[PATH_MAX]; | |
1714 | int err = 0; | |
1715 | FILE *file; | |
166750bc | 1716 | |
8601fd42 AN |
1717 | file = fmemopen((void *)config, strlen(config), "r"); |
1718 | if (!file) { | |
1719 | err = -errno; | |
1720 | pr_warn("failed to open in-memory Kconfig: %d\n", err); | |
1721 | return err; | |
1722 | } | |
1723 | ||
1724 | while (fgets(buf, sizeof(buf), file)) { | |
1725 | err = bpf_object__process_kconfig_line(obj, buf, data); | |
1726 | if (err) { | |
1727 | pr_warn("error parsing in-memory Kconfig line '%s': %d\n", | |
1728 | buf, err); | |
166750bc AN |
1729 | break; |
1730 | } | |
166750bc AN |
1731 | } |
1732 | ||
8601fd42 | 1733 | fclose(file); |
166750bc AN |
1734 | return err; |
1735 | } | |
1736 | ||
81bfdd08 | 1737 | static int bpf_object__init_kconfig_map(struct bpf_object *obj) |
166750bc | 1738 | { |
2e33efe3 | 1739 | struct extern_desc *last_ext = NULL, *ext; |
166750bc | 1740 | size_t map_sz; |
2e33efe3 | 1741 | int i, err; |
166750bc | 1742 | |
2e33efe3 AN |
1743 | for (i = 0; i < obj->nr_extern; i++) { |
1744 | ext = &obj->externs[i]; | |
1745 | if (ext->type == EXT_KCFG) | |
1746 | last_ext = ext; | |
1747 | } | |
166750bc | 1748 | |
2e33efe3 AN |
1749 | if (!last_ext) |
1750 | return 0; | |
166750bc | 1751 | |
2e33efe3 | 1752 | map_sz = last_ext->kcfg.data_off + last_ext->kcfg.sz; |
81bfdd08 | 1753 | err = bpf_object__init_internal_map(obj, LIBBPF_MAP_KCONFIG, |
166750bc AN |
1754 | obj->efile.symbols_shndx, |
1755 | NULL, map_sz); | |
1756 | if (err) | |
1757 | return err; | |
1758 | ||
81bfdd08 | 1759 | obj->kconfig_map_idx = obj->nr_maps - 1; |
166750bc AN |
1760 | |
1761 | return 0; | |
1762 | } | |
1763 | ||
bf829271 | 1764 | static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict) |
561bbcca | 1765 | { |
561bbcca | 1766 | Elf_Data *symbols = obj->efile.symbols; |
bf829271 | 1767 | int i, map_def_sz = 0, nr_maps = 0, nr_syms; |
d859900c | 1768 | Elf_Data *data = NULL; |
bf829271 AN |
1769 | Elf_Scn *scn; |
1770 | ||
1771 | if (obj->efile.maps_shndx < 0) | |
1772 | return 0; | |
561bbcca | 1773 | |
4708bbda EL |
1774 | if (!symbols) |
1775 | return -EINVAL; | |
1776 | ||
88a82120 AN |
1777 | |
1778 | scn = elf_sec_by_idx(obj, obj->efile.maps_shndx); | |
1779 | data = elf_sec_data(obj, scn); | |
bf829271 | 1780 | if (!scn || !data) { |
88a82120 AN |
1781 | pr_warn("elf: failed to get legacy map definitions for %s\n", |
1782 | obj->path); | |
bf829271 | 1783 | return -EINVAL; |
4708bbda | 1784 | } |
561bbcca | 1785 | |
4708bbda EL |
1786 | /* |
1787 | * Count number of maps. Each map has a name. | |
1788 | * Array of maps is not supported: only the first element is | |
1789 | * considered. | |
1790 | * | |
1791 | * TODO: Detect array of map and report error. | |
1792 | */ | |
bf829271 AN |
1793 | nr_syms = symbols->d_size / sizeof(GElf_Sym); |
1794 | for (i = 0; i < nr_syms; i++) { | |
561bbcca | 1795 | GElf_Sym sym; |
4708bbda EL |
1796 | |
1797 | if (!gelf_getsym(symbols, i, &sym)) | |
1798 | continue; | |
1799 | if (sym.st_shndx != obj->efile.maps_shndx) | |
1800 | continue; | |
1801 | nr_maps++; | |
1802 | } | |
b13c5c14 | 1803 | /* Assume equally sized map definitions */ |
88a82120 AN |
1804 | pr_debug("elf: found %d legacy map definitions (%zd bytes) in %s\n", |
1805 | nr_maps, data->d_size, obj->path); | |
bf829271 | 1806 | |
98e527af | 1807 | if (!data->d_size || nr_maps == 0 || (data->d_size % nr_maps) != 0) { |
88a82120 AN |
1808 | pr_warn("elf: unable to determine legacy map definition size in %s\n", |
1809 | obj->path); | |
bf829271 | 1810 | return -EINVAL; |
addb9fc9 | 1811 | } |
98e527af | 1812 | map_def_sz = data->d_size / nr_maps; |
4708bbda | 1813 | |
bf829271 AN |
1814 | /* Fill obj->maps using data in "maps" section. */ |
1815 | for (i = 0; i < nr_syms; i++) { | |
4708bbda | 1816 | GElf_Sym sym; |
561bbcca | 1817 | const char *map_name; |
4708bbda | 1818 | struct bpf_map_def *def; |
bf829271 | 1819 | struct bpf_map *map; |
561bbcca WN |
1820 | |
1821 | if (!gelf_getsym(symbols, i, &sym)) | |
1822 | continue; | |
666810e8 | 1823 | if (sym.st_shndx != obj->efile.maps_shndx) |
561bbcca WN |
1824 | continue; |
1825 | ||
bf829271 AN |
1826 | map = bpf_object__add_map(obj); |
1827 | if (IS_ERR(map)) | |
1828 | return PTR_ERR(map); | |
1829 | ||
88a82120 | 1830 | map_name = elf_sym_str(obj, sym.st_name); |
c51829bb | 1831 | if (!map_name) { |
be18010e KW |
1832 | pr_warn("failed to get map #%d name sym string for obj %s\n", |
1833 | i, obj->path); | |
c51829bb AN |
1834 | return -LIBBPF_ERRNO__FORMAT; |
1835 | } | |
d859900c | 1836 | |
bf829271 | 1837 | map->libbpf_type = LIBBPF_MAP_UNSPEC; |
db48814b AN |
1838 | map->sec_idx = sym.st_shndx; |
1839 | map->sec_offset = sym.st_value; | |
1840 | pr_debug("map '%s' (legacy): at sec_idx %d, offset %zu.\n", | |
1841 | map_name, map->sec_idx, map->sec_offset); | |
b13c5c14 | 1842 | if (sym.st_value + map_def_sz > data->d_size) { |
be18010e KW |
1843 | pr_warn("corrupted maps section in %s: last map \"%s\" too small\n", |
1844 | obj->path, map_name); | |
4708bbda | 1845 | return -EINVAL; |
561bbcca | 1846 | } |
4708bbda | 1847 | |
bf829271 AN |
1848 | map->name = strdup(map_name); |
1849 | if (!map->name) { | |
be18010e | 1850 | pr_warn("failed to alloc map name\n"); |
973170e6 WN |
1851 | return -ENOMEM; |
1852 | } | |
bf829271 | 1853 | pr_debug("map %d is \"%s\"\n", i, map->name); |
4708bbda | 1854 | def = (struct bpf_map_def *)(data->d_buf + sym.st_value); |
b13c5c14 CG |
1855 | /* |
1856 | * If the definition of the map in the object file fits in | |
1857 | * bpf_map_def, copy it. Any extra fields in our version | |
1858 | * of bpf_map_def will default to zero as a result of the | |
1859 | * calloc above. | |
1860 | */ | |
1861 | if (map_def_sz <= sizeof(struct bpf_map_def)) { | |
bf829271 | 1862 | memcpy(&map->def, def, map_def_sz); |
b13c5c14 CG |
1863 | } else { |
1864 | /* | |
1865 | * Here the map structure being read is bigger than what | |
1866 | * we expect, truncate if the excess bits are all zero. | |
1867 | * If they are not zero, reject this map as | |
1868 | * incompatible. | |
1869 | */ | |
1870 | char *b; | |
8983b731 | 1871 | |
b13c5c14 CG |
1872 | for (b = ((char *)def) + sizeof(struct bpf_map_def); |
1873 | b < ((char *)def) + map_def_sz; b++) { | |
1874 | if (*b != 0) { | |
8983b731 | 1875 | pr_warn("maps section in %s: \"%s\" has unrecognized, non-zero options\n", |
be18010e | 1876 | obj->path, map_name); |
c034a177 JF |
1877 | if (strict) |
1878 | return -EINVAL; | |
b13c5c14 CG |
1879 | } |
1880 | } | |
bf829271 | 1881 | memcpy(&map->def, def, sizeof(struct bpf_map_def)); |
b13c5c14 | 1882 | } |
561bbcca | 1883 | } |
bf829271 AN |
1884 | return 0; |
1885 | } | |
4708bbda | 1886 | |
ddc7c304 AN |
1887 | static const struct btf_type * |
1888 | skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id) | |
abd29c93 AN |
1889 | { |
1890 | const struct btf_type *t = btf__type_by_id(btf, id); | |
8837fe5d | 1891 | |
ddc7c304 AN |
1892 | if (res_id) |
1893 | *res_id = id; | |
1894 | ||
1895 | while (btf_is_mod(t) || btf_is_typedef(t)) { | |
1896 | if (res_id) | |
1897 | *res_id = t->type; | |
1898 | t = btf__type_by_id(btf, t->type); | |
abd29c93 | 1899 | } |
ddc7c304 AN |
1900 | |
1901 | return t; | |
abd29c93 AN |
1902 | } |
1903 | ||
590a0088 MKL |
1904 | static const struct btf_type * |
1905 | resolve_func_ptr(const struct btf *btf, __u32 id, __u32 *res_id) | |
1906 | { | |
1907 | const struct btf_type *t; | |
1908 | ||
1909 | t = skip_mods_and_typedefs(btf, id, NULL); | |
1910 | if (!btf_is_ptr(t)) | |
1911 | return NULL; | |
1912 | ||
1913 | t = skip_mods_and_typedefs(btf, t->type, res_id); | |
1914 | ||
1915 | return btf_is_func_proto(t) ? t : NULL; | |
1916 | } | |
1917 | ||
81ba0889 AN |
1918 | static const char *btf_kind_str(const struct btf_type *t) |
1919 | { | |
1920 | switch (btf_kind(t)) { | |
1921 | case BTF_KIND_UNKN: return "void"; | |
1922 | case BTF_KIND_INT: return "int"; | |
1923 | case BTF_KIND_PTR: return "ptr"; | |
1924 | case BTF_KIND_ARRAY: return "array"; | |
1925 | case BTF_KIND_STRUCT: return "struct"; | |
1926 | case BTF_KIND_UNION: return "union"; | |
1927 | case BTF_KIND_ENUM: return "enum"; | |
1928 | case BTF_KIND_FWD: return "fwd"; | |
1929 | case BTF_KIND_TYPEDEF: return "typedef"; | |
1930 | case BTF_KIND_VOLATILE: return "volatile"; | |
1931 | case BTF_KIND_CONST: return "const"; | |
1932 | case BTF_KIND_RESTRICT: return "restrict"; | |
1933 | case BTF_KIND_FUNC: return "func"; | |
1934 | case BTF_KIND_FUNC_PROTO: return "func_proto"; | |
1935 | case BTF_KIND_VAR: return "var"; | |
1936 | case BTF_KIND_DATASEC: return "datasec"; | |
1937 | default: return "unknown"; | |
1938 | } | |
1939 | } | |
1940 | ||
ef99b02b AN |
1941 | /* |
1942 | * Fetch integer attribute of BTF map definition. Such attributes are | |
1943 | * represented using a pointer to an array, in which dimensionality of array | |
1944 | * encodes specified integer value. E.g., int (*type)[BPF_MAP_TYPE_ARRAY]; | |
1945 | * encodes `type => BPF_MAP_TYPE_ARRAY` key/value pair completely using BTF | |
1946 | * type definition, while using only sizeof(void *) space in ELF data section. | |
1947 | */ | |
1948 | static bool get_map_field_int(const char *map_name, const struct btf *btf, | |
8983b731 AN |
1949 | const struct btf_member *m, __u32 *res) |
1950 | { | |
ddc7c304 | 1951 | const struct btf_type *t = skip_mods_and_typedefs(btf, m->type, NULL); |
abd29c93 | 1952 | const char *name = btf__name_by_offset(btf, m->name_off); |
ef99b02b AN |
1953 | const struct btf_array *arr_info; |
1954 | const struct btf_type *arr_t; | |
abd29c93 | 1955 | |
b03bc685 | 1956 | if (!btf_is_ptr(t)) { |
81ba0889 AN |
1957 | pr_warn("map '%s': attr '%s': expected PTR, got %s.\n", |
1958 | map_name, name, btf_kind_str(t)); | |
abd29c93 AN |
1959 | return false; |
1960 | } | |
ef99b02b AN |
1961 | |
1962 | arr_t = btf__type_by_id(btf, t->type); | |
1963 | if (!arr_t) { | |
be18010e KW |
1964 | pr_warn("map '%s': attr '%s': type [%u] not found.\n", |
1965 | map_name, name, t->type); | |
abd29c93 AN |
1966 | return false; |
1967 | } | |
b03bc685 | 1968 | if (!btf_is_array(arr_t)) { |
81ba0889 AN |
1969 | pr_warn("map '%s': attr '%s': expected ARRAY, got %s.\n", |
1970 | map_name, name, btf_kind_str(arr_t)); | |
abd29c93 AN |
1971 | return false; |
1972 | } | |
b03bc685 | 1973 | arr_info = btf_array(arr_t); |
ef99b02b | 1974 | *res = arr_info->nelems; |
abd29c93 AN |
1975 | return true; |
1976 | } | |
1977 | ||
57a00f41 THJ |
1978 | static int build_map_pin_path(struct bpf_map *map, const char *path) |
1979 | { | |
1980 | char buf[PATH_MAX]; | |
6e9cab2e | 1981 | int len; |
57a00f41 THJ |
1982 | |
1983 | if (!path) | |
1984 | path = "/sys/fs/bpf"; | |
1985 | ||
1986 | len = snprintf(buf, PATH_MAX, "%s/%s", path, bpf_map__name(map)); | |
1987 | if (len < 0) | |
1988 | return -EINVAL; | |
1989 | else if (len >= PATH_MAX) | |
1990 | return -ENAMETOOLONG; | |
1991 | ||
6e9cab2e | 1992 | return bpf_map__set_pin_path(map, buf); |
57a00f41 THJ |
1993 | } |
1994 | ||
41017e56 AN |
1995 | |
1996 | static int parse_btf_map_def(struct bpf_object *obj, | |
1997 | struct bpf_map *map, | |
1998 | const struct btf_type *def, | |
646f02ff | 1999 | bool strict, bool is_inner, |
41017e56 | 2000 | const char *pin_root_path) |
abd29c93 | 2001 | { |
41017e56 | 2002 | const struct btf_type *t; |
abd29c93 | 2003 | const struct btf_member *m; |
abd29c93 AN |
2004 | int vlen, i; |
2005 | ||
b03bc685 AN |
2006 | vlen = btf_vlen(def); |
2007 | m = btf_members(def); | |
abd29c93 AN |
2008 | for (i = 0; i < vlen; i++, m++) { |
2009 | const char *name = btf__name_by_offset(obj->btf, m->name_off); | |
2010 | ||
2011 | if (!name) { | |
41017e56 | 2012 | pr_warn("map '%s': invalid field #%d.\n", map->name, i); |
abd29c93 AN |
2013 | return -EINVAL; |
2014 | } | |
2015 | if (strcmp(name, "type") == 0) { | |
41017e56 | 2016 | if (!get_map_field_int(map->name, obj->btf, m, |
ef99b02b | 2017 | &map->def.type)) |
abd29c93 AN |
2018 | return -EINVAL; |
2019 | pr_debug("map '%s': found type = %u.\n", | |
41017e56 | 2020 | map->name, map->def.type); |
abd29c93 | 2021 | } else if (strcmp(name, "max_entries") == 0) { |
41017e56 | 2022 | if (!get_map_field_int(map->name, obj->btf, m, |
ef99b02b | 2023 | &map->def.max_entries)) |
abd29c93 AN |
2024 | return -EINVAL; |
2025 | pr_debug("map '%s': found max_entries = %u.\n", | |
41017e56 | 2026 | map->name, map->def.max_entries); |
abd29c93 | 2027 | } else if (strcmp(name, "map_flags") == 0) { |
41017e56 | 2028 | if (!get_map_field_int(map->name, obj->btf, m, |
ef99b02b | 2029 | &map->def.map_flags)) |
abd29c93 AN |
2030 | return -EINVAL; |
2031 | pr_debug("map '%s': found map_flags = %u.\n", | |
41017e56 | 2032 | map->name, map->def.map_flags); |
1bdb6c9a AN |
2033 | } else if (strcmp(name, "numa_node") == 0) { |
2034 | if (!get_map_field_int(map->name, obj->btf, m, &map->numa_node)) | |
2035 | return -EINVAL; | |
2036 | pr_debug("map '%s': found numa_node = %u.\n", map->name, map->numa_node); | |
abd29c93 AN |
2037 | } else if (strcmp(name, "key_size") == 0) { |
2038 | __u32 sz; | |
2039 | ||
41017e56 | 2040 | if (!get_map_field_int(map->name, obj->btf, m, &sz)) |
abd29c93 AN |
2041 | return -EINVAL; |
2042 | pr_debug("map '%s': found key_size = %u.\n", | |
41017e56 | 2043 | map->name, sz); |
abd29c93 | 2044 | if (map->def.key_size && map->def.key_size != sz) { |
be18010e | 2045 | pr_warn("map '%s': conflicting key size %u != %u.\n", |
41017e56 | 2046 | map->name, map->def.key_size, sz); |
abd29c93 AN |
2047 | return -EINVAL; |
2048 | } | |
2049 | map->def.key_size = sz; | |
2050 | } else if (strcmp(name, "key") == 0) { | |
2051 | __s64 sz; | |
2052 | ||
2053 | t = btf__type_by_id(obj->btf, m->type); | |
2054 | if (!t) { | |
be18010e | 2055 | pr_warn("map '%s': key type [%d] not found.\n", |
41017e56 | 2056 | map->name, m->type); |
abd29c93 AN |
2057 | return -EINVAL; |
2058 | } | |
b03bc685 | 2059 | if (!btf_is_ptr(t)) { |
81ba0889 AN |
2060 | pr_warn("map '%s': key spec is not PTR: %s.\n", |
2061 | map->name, btf_kind_str(t)); | |
abd29c93 AN |
2062 | return -EINVAL; |
2063 | } | |
2064 | sz = btf__resolve_size(obj->btf, t->type); | |
2065 | if (sz < 0) { | |
679152d3 | 2066 | pr_warn("map '%s': can't determine key size for type [%u]: %zd.\n", |
41017e56 | 2067 | map->name, t->type, (ssize_t)sz); |
abd29c93 AN |
2068 | return sz; |
2069 | } | |
679152d3 | 2070 | pr_debug("map '%s': found key [%u], sz = %zd.\n", |
41017e56 | 2071 | map->name, t->type, (ssize_t)sz); |
abd29c93 | 2072 | if (map->def.key_size && map->def.key_size != sz) { |
679152d3 | 2073 | pr_warn("map '%s': conflicting key size %u != %zd.\n", |
41017e56 | 2074 | map->name, map->def.key_size, (ssize_t)sz); |
abd29c93 AN |
2075 | return -EINVAL; |
2076 | } | |
2077 | map->def.key_size = sz; | |
2078 | map->btf_key_type_id = t->type; | |
2079 | } else if (strcmp(name, "value_size") == 0) { | |
2080 | __u32 sz; | |
2081 | ||
41017e56 | 2082 | if (!get_map_field_int(map->name, obj->btf, m, &sz)) |
abd29c93 AN |
2083 | return -EINVAL; |
2084 | pr_debug("map '%s': found value_size = %u.\n", | |
41017e56 | 2085 | map->name, sz); |
abd29c93 | 2086 | if (map->def.value_size && map->def.value_size != sz) { |
be18010e | 2087 | pr_warn("map '%s': conflicting value size %u != %u.\n", |
41017e56 | 2088 | map->name, map->def.value_size, sz); |
abd29c93 AN |
2089 | return -EINVAL; |
2090 | } | |
2091 | map->def.value_size = sz; | |
2092 | } else if (strcmp(name, "value") == 0) { | |
2093 | __s64 sz; | |
2094 | ||
2095 | t = btf__type_by_id(obj->btf, m->type); | |
2096 | if (!t) { | |
be18010e | 2097 | pr_warn("map '%s': value type [%d] not found.\n", |
41017e56 | 2098 | map->name, m->type); |
abd29c93 AN |
2099 | return -EINVAL; |
2100 | } | |
b03bc685 | 2101 | if (!btf_is_ptr(t)) { |
81ba0889 AN |
2102 | pr_warn("map '%s': value spec is not PTR: %s.\n", |
2103 | map->name, btf_kind_str(t)); | |
abd29c93 AN |
2104 | return -EINVAL; |
2105 | } | |
2106 | sz = btf__resolve_size(obj->btf, t->type); | |
2107 | if (sz < 0) { | |
679152d3 | 2108 | pr_warn("map '%s': can't determine value size for type [%u]: %zd.\n", |
41017e56 | 2109 | map->name, t->type, (ssize_t)sz); |
abd29c93 AN |
2110 | return sz; |
2111 | } | |
679152d3 | 2112 | pr_debug("map '%s': found value [%u], sz = %zd.\n", |
41017e56 | 2113 | map->name, t->type, (ssize_t)sz); |
abd29c93 | 2114 | if (map->def.value_size && map->def.value_size != sz) { |
679152d3 | 2115 | pr_warn("map '%s': conflicting value size %u != %zd.\n", |
41017e56 | 2116 | map->name, map->def.value_size, (ssize_t)sz); |
abd29c93 AN |
2117 | return -EINVAL; |
2118 | } | |
2119 | map->def.value_size = sz; | |
2120 | map->btf_value_type_id = t->type; | |
646f02ff AN |
2121 | } |
2122 | else if (strcmp(name, "values") == 0) { | |
2123 | int err; | |
2124 | ||
2125 | if (is_inner) { | |
2126 | pr_warn("map '%s': multi-level inner maps not supported.\n", | |
2127 | map->name); | |
2128 | return -ENOTSUP; | |
2129 | } | |
2130 | if (i != vlen - 1) { | |
2131 | pr_warn("map '%s': '%s' member should be last.\n", | |
2132 | map->name, name); | |
2133 | return -EINVAL; | |
2134 | } | |
2135 | if (!bpf_map_type__is_map_in_map(map->def.type)) { | |
2136 | pr_warn("map '%s': should be map-in-map.\n", | |
2137 | map->name); | |
2138 | return -ENOTSUP; | |
2139 | } | |
2140 | if (map->def.value_size && map->def.value_size != 4) { | |
2141 | pr_warn("map '%s': conflicting value size %u != 4.\n", | |
2142 | map->name, map->def.value_size); | |
2143 | return -EINVAL; | |
2144 | } | |
2145 | map->def.value_size = 4; | |
2146 | t = btf__type_by_id(obj->btf, m->type); | |
2147 | if (!t) { | |
2148 | pr_warn("map '%s': map-in-map inner type [%d] not found.\n", | |
2149 | map->name, m->type); | |
2150 | return -EINVAL; | |
2151 | } | |
2152 | if (!btf_is_array(t) || btf_array(t)->nelems) { | |
2153 | pr_warn("map '%s': map-in-map inner spec is not a zero-sized array.\n", | |
2154 | map->name); | |
2155 | return -EINVAL; | |
2156 | } | |
2157 | t = skip_mods_and_typedefs(obj->btf, btf_array(t)->type, | |
2158 | NULL); | |
2159 | if (!btf_is_ptr(t)) { | |
81ba0889 AN |
2160 | pr_warn("map '%s': map-in-map inner def is of unexpected kind %s.\n", |
2161 | map->name, btf_kind_str(t)); | |
646f02ff AN |
2162 | return -EINVAL; |
2163 | } | |
2164 | t = skip_mods_and_typedefs(obj->btf, t->type, NULL); | |
2165 | if (!btf_is_struct(t)) { | |
81ba0889 AN |
2166 | pr_warn("map '%s': map-in-map inner def is of unexpected kind %s.\n", |
2167 | map->name, btf_kind_str(t)); | |
646f02ff AN |
2168 | return -EINVAL; |
2169 | } | |
2170 | ||
2171 | map->inner_map = calloc(1, sizeof(*map->inner_map)); | |
2172 | if (!map->inner_map) | |
2173 | return -ENOMEM; | |
2174 | map->inner_map->sec_idx = obj->efile.btf_maps_shndx; | |
2175 | map->inner_map->name = malloc(strlen(map->name) + | |
2176 | sizeof(".inner") + 1); | |
2177 | if (!map->inner_map->name) | |
2178 | return -ENOMEM; | |
2179 | sprintf(map->inner_map->name, "%s.inner", map->name); | |
2180 | ||
2181 | err = parse_btf_map_def(obj, map->inner_map, t, strict, | |
2182 | true /* is_inner */, NULL); | |
2183 | if (err) | |
2184 | return err; | |
57a00f41 THJ |
2185 | } else if (strcmp(name, "pinning") == 0) { |
2186 | __u32 val; | |
2187 | int err; | |
2188 | ||
646f02ff AN |
2189 | if (is_inner) { |
2190 | pr_debug("map '%s': inner def can't be pinned.\n", | |
2191 | map->name); | |
2192 | return -EINVAL; | |
2193 | } | |
41017e56 | 2194 | if (!get_map_field_int(map->name, obj->btf, m, &val)) |
57a00f41 THJ |
2195 | return -EINVAL; |
2196 | pr_debug("map '%s': found pinning = %u.\n", | |
41017e56 | 2197 | map->name, val); |
57a00f41 THJ |
2198 | |
2199 | if (val != LIBBPF_PIN_NONE && | |
2200 | val != LIBBPF_PIN_BY_NAME) { | |
2201 | pr_warn("map '%s': invalid pinning value %u.\n", | |
41017e56 | 2202 | map->name, val); |
57a00f41 THJ |
2203 | return -EINVAL; |
2204 | } | |
2205 | if (val == LIBBPF_PIN_BY_NAME) { | |
2206 | err = build_map_pin_path(map, pin_root_path); | |
2207 | if (err) { | |
2208 | pr_warn("map '%s': couldn't build pin path.\n", | |
41017e56 | 2209 | map->name); |
57a00f41 THJ |
2210 | return err; |
2211 | } | |
2212 | } | |
abd29c93 AN |
2213 | } else { |
2214 | if (strict) { | |
be18010e | 2215 | pr_warn("map '%s': unknown field '%s'.\n", |
41017e56 | 2216 | map->name, name); |
abd29c93 AN |
2217 | return -ENOTSUP; |
2218 | } | |
2219 | pr_debug("map '%s': ignoring unknown field '%s'.\n", | |
41017e56 | 2220 | map->name, name); |
abd29c93 AN |
2221 | } |
2222 | } | |
2223 | ||
2224 | if (map->def.type == BPF_MAP_TYPE_UNSPEC) { | |
41017e56 | 2225 | pr_warn("map '%s': map type isn't specified.\n", map->name); |
abd29c93 AN |
2226 | return -EINVAL; |
2227 | } | |
2228 | ||
2229 | return 0; | |
2230 | } | |
2231 | ||
41017e56 AN |
2232 | static int bpf_object__init_user_btf_map(struct bpf_object *obj, |
2233 | const struct btf_type *sec, | |
2234 | int var_idx, int sec_idx, | |
2235 | const Elf_Data *data, bool strict, | |
2236 | const char *pin_root_path) | |
2237 | { | |
2238 | const struct btf_type *var, *def; | |
2239 | const struct btf_var_secinfo *vi; | |
2240 | const struct btf_var *var_extra; | |
2241 | const char *map_name; | |
2242 | struct bpf_map *map; | |
2243 | ||
2244 | vi = btf_var_secinfos(sec) + var_idx; | |
2245 | var = btf__type_by_id(obj->btf, vi->type); | |
2246 | var_extra = btf_var(var); | |
2247 | map_name = btf__name_by_offset(obj->btf, var->name_off); | |
2248 | ||
2249 | if (map_name == NULL || map_name[0] == '\0') { | |
2250 | pr_warn("map #%d: empty name.\n", var_idx); | |
2251 | return -EINVAL; | |
2252 | } | |
2253 | if ((__u64)vi->offset + vi->size > data->d_size) { | |
2254 | pr_warn("map '%s' BTF data is corrupted.\n", map_name); | |
2255 | return -EINVAL; | |
2256 | } | |
2257 | if (!btf_is_var(var)) { | |
81ba0889 AN |
2258 | pr_warn("map '%s': unexpected var kind %s.\n", |
2259 | map_name, btf_kind_str(var)); | |
41017e56 AN |
2260 | return -EINVAL; |
2261 | } | |
2262 | if (var_extra->linkage != BTF_VAR_GLOBAL_ALLOCATED && | |
2263 | var_extra->linkage != BTF_VAR_STATIC) { | |
2264 | pr_warn("map '%s': unsupported var linkage %u.\n", | |
2265 | map_name, var_extra->linkage); | |
2266 | return -EOPNOTSUPP; | |
2267 | } | |
2268 | ||
2269 | def = skip_mods_and_typedefs(obj->btf, var->type, NULL); | |
2270 | if (!btf_is_struct(def)) { | |
81ba0889 AN |
2271 | pr_warn("map '%s': unexpected def kind %s.\n", |
2272 | map_name, btf_kind_str(var)); | |
41017e56 AN |
2273 | return -EINVAL; |
2274 | } | |
2275 | if (def->size > vi->size) { | |
2276 | pr_warn("map '%s': invalid def size.\n", map_name); | |
2277 | return -EINVAL; | |
2278 | } | |
2279 | ||
2280 | map = bpf_object__add_map(obj); | |
2281 | if (IS_ERR(map)) | |
2282 | return PTR_ERR(map); | |
2283 | map->name = strdup(map_name); | |
2284 | if (!map->name) { | |
2285 | pr_warn("map '%s': failed to alloc map name.\n", map_name); | |
2286 | return -ENOMEM; | |
2287 | } | |
2288 | map->libbpf_type = LIBBPF_MAP_UNSPEC; | |
2289 | map->def.type = BPF_MAP_TYPE_UNSPEC; | |
2290 | map->sec_idx = sec_idx; | |
2291 | map->sec_offset = vi->offset; | |
646f02ff | 2292 | map->btf_var_idx = var_idx; |
41017e56 AN |
2293 | pr_debug("map '%s': at sec_idx %d, offset %zu.\n", |
2294 | map_name, map->sec_idx, map->sec_offset); | |
2295 | ||
646f02ff | 2296 | return parse_btf_map_def(obj, map, def, strict, false, pin_root_path); |
41017e56 AN |
2297 | } |
2298 | ||
57a00f41 THJ |
2299 | static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict, |
2300 | const char *pin_root_path) | |
abd29c93 AN |
2301 | { |
2302 | const struct btf_type *sec = NULL; | |
2303 | int nr_types, i, vlen, err; | |
2304 | const struct btf_type *t; | |
2305 | const char *name; | |
2306 | Elf_Data *data; | |
2307 | Elf_Scn *scn; | |
2308 | ||
2309 | if (obj->efile.btf_maps_shndx < 0) | |
2310 | return 0; | |
2311 | ||
88a82120 AN |
2312 | scn = elf_sec_by_idx(obj, obj->efile.btf_maps_shndx); |
2313 | data = elf_sec_data(obj, scn); | |
abd29c93 | 2314 | if (!scn || !data) { |
88a82120 AN |
2315 | pr_warn("elf: failed to get %s map definitions for %s\n", |
2316 | MAPS_ELF_SEC, obj->path); | |
abd29c93 AN |
2317 | return -EINVAL; |
2318 | } | |
2319 | ||
2320 | nr_types = btf__get_nr_types(obj->btf); | |
2321 | for (i = 1; i <= nr_types; i++) { | |
2322 | t = btf__type_by_id(obj->btf, i); | |
b03bc685 | 2323 | if (!btf_is_datasec(t)) |
abd29c93 AN |
2324 | continue; |
2325 | name = btf__name_by_offset(obj->btf, t->name_off); | |
2326 | if (strcmp(name, MAPS_ELF_SEC) == 0) { | |
2327 | sec = t; | |
646f02ff | 2328 | obj->efile.btf_maps_sec_btf_id = i; |
abd29c93 AN |
2329 | break; |
2330 | } | |
2331 | } | |
2332 | ||
2333 | if (!sec) { | |
be18010e | 2334 | pr_warn("DATASEC '%s' not found.\n", MAPS_ELF_SEC); |
abd29c93 AN |
2335 | return -ENOENT; |
2336 | } | |
2337 | ||
b03bc685 | 2338 | vlen = btf_vlen(sec); |
abd29c93 AN |
2339 | for (i = 0; i < vlen; i++) { |
2340 | err = bpf_object__init_user_btf_map(obj, sec, i, | |
2341 | obj->efile.btf_maps_shndx, | |
8983b731 AN |
2342 | data, strict, |
2343 | pin_root_path); | |
abd29c93 AN |
2344 | if (err) |
2345 | return err; | |
2346 | } | |
2347 | ||
2348 | return 0; | |
2349 | } | |
2350 | ||
0d13bfce | 2351 | static int bpf_object__init_maps(struct bpf_object *obj, |
01af3bf0 | 2352 | const struct bpf_object_open_opts *opts) |
bf829271 | 2353 | { |
166750bc AN |
2354 | const char *pin_root_path; |
2355 | bool strict; | |
bf829271 | 2356 | int err; |
8837fe5d | 2357 | |
166750bc AN |
2358 | strict = !OPTS_GET(opts, relaxed_maps, false); |
2359 | pin_root_path = OPTS_GET(opts, pin_root_path, NULL); | |
bf829271 | 2360 | |
166750bc AN |
2361 | err = bpf_object__init_user_maps(obj, strict); |
2362 | err = err ?: bpf_object__init_user_btf_maps(obj, strict, pin_root_path); | |
2363 | err = err ?: bpf_object__init_global_data_maps(obj); | |
81bfdd08 | 2364 | err = err ?: bpf_object__init_kconfig_map(obj); |
590a0088 | 2365 | err = err ?: bpf_object__init_struct_ops_maps(obj); |
bf829271 AN |
2366 | if (err) |
2367 | return err; | |
2368 | ||
bf829271 | 2369 | return 0; |
561bbcca WN |
2370 | } |
2371 | ||
e3d91b0c JDB |
2372 | static bool section_have_execinstr(struct bpf_object *obj, int idx) |
2373 | { | |
e3d91b0c JDB |
2374 | GElf_Shdr sh; |
2375 | ||
88a82120 | 2376 | if (elf_sec_hdr(obj, elf_sec_by_idx(obj, idx), &sh)) |
e3d91b0c JDB |
2377 | return false; |
2378 | ||
88a82120 | 2379 | return sh.sh_flags & SHF_EXECINSTR; |
e3d91b0c JDB |
2380 | } |
2381 | ||
0f0e55d8 AN |
2382 | static bool btf_needs_sanitization(struct bpf_object *obj) |
2383 | { | |
47b6cb4d AN |
2384 | bool has_func_global = kernel_supports(FEAT_BTF_GLOBAL_FUNC); |
2385 | bool has_datasec = kernel_supports(FEAT_BTF_DATASEC); | |
2386 | bool has_func = kernel_supports(FEAT_BTF_FUNC); | |
0f0e55d8 AN |
2387 | |
2388 | return !has_func || !has_datasec || !has_func_global; | |
2389 | } | |
2390 | ||
2391 | static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf) | |
d7c4b398 | 2392 | { |
47b6cb4d AN |
2393 | bool has_func_global = kernel_supports(FEAT_BTF_GLOBAL_FUNC); |
2394 | bool has_datasec = kernel_supports(FEAT_BTF_DATASEC); | |
2395 | bool has_func = kernel_supports(FEAT_BTF_FUNC); | |
d7c4b398 AN |
2396 | struct btf_type *t; |
2397 | int i, j, vlen; | |
d7c4b398 | 2398 | |
d7c4b398 AN |
2399 | for (i = 1; i <= btf__get_nr_types(btf); i++) { |
2400 | t = (struct btf_type *)btf__type_by_id(btf, i); | |
d7c4b398 | 2401 | |
b03bc685 | 2402 | if (!has_datasec && btf_is_var(t)) { |
d7c4b398 AN |
2403 | /* replace VAR with INT */ |
2404 | t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0); | |
1d4126c4 AN |
2405 | /* |
2406 | * using size = 1 is the safest choice, 4 will be too | |
2407 | * big and cause kernel BTF validation failure if | |
2408 | * original variable took less than 4 bytes | |
2409 | */ | |
2410 | t->size = 1; | |
708852dc | 2411 | *(int *)(t + 1) = BTF_INT_ENC(0, 0, 8); |
b03bc685 | 2412 | } else if (!has_datasec && btf_is_datasec(t)) { |
d7c4b398 | 2413 | /* replace DATASEC with STRUCT */ |
b03bc685 AN |
2414 | const struct btf_var_secinfo *v = btf_var_secinfos(t); |
2415 | struct btf_member *m = btf_members(t); | |
d7c4b398 AN |
2416 | struct btf_type *vt; |
2417 | char *name; | |
2418 | ||
2419 | name = (char *)btf__name_by_offset(btf, t->name_off); | |
2420 | while (*name) { | |
2421 | if (*name == '.') | |
2422 | *name = '_'; | |
2423 | name++; | |
2424 | } | |
2425 | ||
b03bc685 | 2426 | vlen = btf_vlen(t); |
d7c4b398 AN |
2427 | t->info = BTF_INFO_ENC(BTF_KIND_STRUCT, 0, vlen); |
2428 | for (j = 0; j < vlen; j++, v++, m++) { | |
2429 | /* order of field assignments is important */ | |
2430 | m->offset = v->offset * 8; | |
2431 | m->type = v->type; | |
2432 | /* preserve variable name as member name */ | |
2433 | vt = (void *)btf__type_by_id(btf, v->type); | |
2434 | m->name_off = vt->name_off; | |
2435 | } | |
b03bc685 | 2436 | } else if (!has_func && btf_is_func_proto(t)) { |
d7c4b398 | 2437 | /* replace FUNC_PROTO with ENUM */ |
b03bc685 | 2438 | vlen = btf_vlen(t); |
d7c4b398 AN |
2439 | t->info = BTF_INFO_ENC(BTF_KIND_ENUM, 0, vlen); |
2440 | t->size = sizeof(__u32); /* kernel enforced */ | |
b03bc685 | 2441 | } else if (!has_func && btf_is_func(t)) { |
d7c4b398 AN |
2442 | /* replace FUNC with TYPEDEF */ |
2443 | t->info = BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0); | |
2d3eb67f AS |
2444 | } else if (!has_func_global && btf_is_func(t)) { |
2445 | /* replace BTF_FUNC_GLOBAL with BTF_FUNC_STATIC */ | |
2446 | t->info = BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0); | |
d7c4b398 AN |
2447 | } |
2448 | } | |
2449 | } | |
2450 | ||
b35f14f4 | 2451 | static bool libbpf_needs_btf(const struct bpf_object *obj) |
abd29c93 | 2452 | { |
b35f14f4 AN |
2453 | return obj->efile.btf_maps_shndx >= 0 || |
2454 | obj->efile.st_ops_shndx >= 0 || | |
2455 | obj->nr_extern > 0; | |
2456 | } | |
2457 | ||
2458 | static bool kernel_needs_btf(const struct bpf_object *obj) | |
2459 | { | |
2460 | return obj->efile.st_ops_shndx >= 0; | |
abd29c93 AN |
2461 | } |
2462 | ||
063183bf | 2463 | static int bpf_object__init_btf(struct bpf_object *obj, |
9c6660d0 AN |
2464 | Elf_Data *btf_data, |
2465 | Elf_Data *btf_ext_data) | |
2466 | { | |
b7d7f3e1 | 2467 | int err = -ENOENT; |
9c6660d0 AN |
2468 | |
2469 | if (btf_data) { | |
2470 | obj->btf = btf__new(btf_data->d_buf, btf_data->d_size); | |
2471 | if (IS_ERR(obj->btf)) { | |
b7d7f3e1 AN |
2472 | err = PTR_ERR(obj->btf); |
2473 | obj->btf = NULL; | |
be18010e KW |
2474 | pr_warn("Error loading ELF section %s: %d.\n", |
2475 | BTF_ELF_SEC, err); | |
9c6660d0 AN |
2476 | goto out; |
2477 | } | |
4c01925f AN |
2478 | /* enforce 8-byte pointers for BPF-targeted BTFs */ |
2479 | btf__set_pointer_size(obj->btf, 8); | |
b7d7f3e1 | 2480 | err = 0; |
9c6660d0 AN |
2481 | } |
2482 | if (btf_ext_data) { | |
2483 | if (!obj->btf) { | |
2484 | pr_debug("Ignore ELF section %s because its depending ELF section %s is not found.\n", | |
2485 | BTF_EXT_ELF_SEC, BTF_ELF_SEC); | |
2486 | goto out; | |
2487 | } | |
2488 | obj->btf_ext = btf_ext__new(btf_ext_data->d_buf, | |
2489 | btf_ext_data->d_size); | |
2490 | if (IS_ERR(obj->btf_ext)) { | |
be18010e KW |
2491 | pr_warn("Error loading ELF section %s: %ld. Ignored and continue.\n", |
2492 | BTF_EXT_ELF_SEC, PTR_ERR(obj->btf_ext)); | |
9c6660d0 AN |
2493 | obj->btf_ext = NULL; |
2494 | goto out; | |
2495 | } | |
9c6660d0 AN |
2496 | } |
2497 | out: | |
b35f14f4 | 2498 | if (err && libbpf_needs_btf(obj)) { |
be18010e | 2499 | pr_warn("BTF is required, but is missing or corrupted.\n"); |
b7d7f3e1 | 2500 | return err; |
abd29c93 | 2501 | } |
9c6660d0 AN |
2502 | return 0; |
2503 | } | |
2504 | ||
166750bc AN |
2505 | static int bpf_object__finalize_btf(struct bpf_object *obj) |
2506 | { | |
2507 | int err; | |
2508 | ||
2509 | if (!obj->btf) | |
2510 | return 0; | |
2511 | ||
2512 | err = btf__finalize_data(obj, obj->btf); | |
bfc96656 AN |
2513 | if (err) { |
2514 | pr_warn("Error finalizing %s: %d.\n", BTF_ELF_SEC, err); | |
2515 | return err; | |
166750bc | 2516 | } |
bfc96656 | 2517 | |
166750bc AN |
2518 | return 0; |
2519 | } | |
2520 | ||
a6ed02ca KS |
2521 | static inline bool libbpf_prog_needs_vmlinux_btf(struct bpf_program *prog) |
2522 | { | |
1e092a03 KS |
2523 | if (prog->type == BPF_PROG_TYPE_STRUCT_OPS || |
2524 | prog->type == BPF_PROG_TYPE_LSM) | |
a6ed02ca KS |
2525 | return true; |
2526 | ||
2527 | /* BPF_PROG_TYPE_TRACING programs which do not attach to other programs | |
2528 | * also need vmlinux BTF | |
2529 | */ | |
2530 | if (prog->type == BPF_PROG_TYPE_TRACING && !prog->attach_prog_fd) | |
2531 | return true; | |
2532 | ||
2533 | return false; | |
2534 | } | |
2535 | ||
2536 | static int bpf_object__load_vmlinux_btf(struct bpf_object *obj) | |
2537 | { | |
192b6638 | 2538 | bool need_vmlinux_btf = false; |
a6ed02ca | 2539 | struct bpf_program *prog; |
d370bbe1 | 2540 | int i, err; |
a6ed02ca | 2541 | |
192b6638 | 2542 | /* CO-RE relocations need kernel BTF */ |
28b93c64 | 2543 | if (obj->btf_ext && obj->btf_ext->core_relo_info.len) |
192b6638 AN |
2544 | need_vmlinux_btf = true; |
2545 | ||
d370bbe1 HL |
2546 | /* Support for typed ksyms needs kernel BTF */ |
2547 | for (i = 0; i < obj->nr_extern; i++) { | |
2548 | const struct extern_desc *ext; | |
2549 | ||
2550 | ext = &obj->externs[i]; | |
2551 | if (ext->type == EXT_KSYM && ext->ksym.type_id) { | |
2552 | need_vmlinux_btf = true; | |
2553 | break; | |
2554 | } | |
2555 | } | |
2556 | ||
a6ed02ca | 2557 | bpf_object__for_each_program(prog, obj) { |
d9297581 AN |
2558 | if (!prog->load) |
2559 | continue; | |
a6ed02ca | 2560 | if (libbpf_prog_needs_vmlinux_btf(prog)) { |
192b6638 AN |
2561 | need_vmlinux_btf = true; |
2562 | break; | |
a6ed02ca KS |
2563 | } |
2564 | } | |
2565 | ||
192b6638 AN |
2566 | if (!need_vmlinux_btf) |
2567 | return 0; | |
2568 | ||
2569 | obj->btf_vmlinux = libbpf_find_kernel_btf(); | |
2570 | if (IS_ERR(obj->btf_vmlinux)) { | |
2571 | err = PTR_ERR(obj->btf_vmlinux); | |
2572 | pr_warn("Error loading vmlinux BTF: %d\n", err); | |
2573 | obj->btf_vmlinux = NULL; | |
2574 | return err; | |
2575 | } | |
a6ed02ca KS |
2576 | return 0; |
2577 | } | |
2578 | ||
063183bf AN |
2579 | static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) |
2580 | { | |
0f0e55d8 AN |
2581 | struct btf *kern_btf = obj->btf; |
2582 | bool btf_mandatory, sanitize; | |
063183bf AN |
2583 | int err = 0; |
2584 | ||
2585 | if (!obj->btf) | |
2586 | return 0; | |
2587 | ||
68b08647 AN |
2588 | if (!kernel_supports(FEAT_BTF)) { |
2589 | if (kernel_needs_btf(obj)) { | |
2590 | err = -EOPNOTSUPP; | |
2591 | goto report; | |
2592 | } | |
2593 | pr_debug("Kernel doesn't support BTF, skipping uploading it.\n"); | |
2594 | return 0; | |
2595 | } | |
2596 | ||
0f0e55d8 AN |
2597 | sanitize = btf_needs_sanitization(obj); |
2598 | if (sanitize) { | |
5c3320d7 | 2599 | const void *raw_data; |
0f0e55d8 | 2600 | __u32 sz; |
063183bf | 2601 | |
0f0e55d8 | 2602 | /* clone BTF to sanitize a copy and leave the original intact */ |
5c3320d7 AN |
2603 | raw_data = btf__get_raw_data(obj->btf, &sz); |
2604 | kern_btf = btf__new(raw_data, sz); | |
0f0e55d8 AN |
2605 | if (IS_ERR(kern_btf)) |
2606 | return PTR_ERR(kern_btf); | |
04efe591 | 2607 | |
4c01925f AN |
2608 | /* enforce 8-byte pointers for BPF-targeted BTFs */ |
2609 | btf__set_pointer_size(obj->btf, 8); | |
0f0e55d8 | 2610 | bpf_object__sanitize_btf(obj, kern_btf); |
063183bf | 2611 | } |
0f0e55d8 AN |
2612 | |
2613 | err = btf__load(kern_btf); | |
2614 | if (sanitize) { | |
2615 | if (!err) { | |
2616 | /* move fd to libbpf's BTF */ | |
2617 | btf__set_fd(obj->btf, btf__fd(kern_btf)); | |
2618 | btf__set_fd(kern_btf, -1); | |
2619 | } | |
2620 | btf__free(kern_btf); | |
2621 | } | |
68b08647 | 2622 | report: |
0f0e55d8 AN |
2623 | if (err) { |
2624 | btf_mandatory = kernel_needs_btf(obj); | |
2625 | pr_warn("Error loading .BTF into kernel: %d. %s\n", err, | |
2626 | btf_mandatory ? "BTF is mandatory, can't proceed." | |
2627 | : "BTF is optional, ignoring."); | |
2628 | if (!btf_mandatory) | |
2629 | err = 0; | |
2630 | } | |
2631 | return err; | |
063183bf AN |
2632 | } |
2633 | ||
88a82120 AN |
2634 | static const char *elf_sym_str(const struct bpf_object *obj, size_t off) |
2635 | { | |
2636 | const char *name; | |
2637 | ||
2638 | name = elf_strptr(obj->efile.elf, obj->efile.strtabidx, off); | |
2639 | if (!name) { | |
2640 | pr_warn("elf: failed to get section name string at offset %zu from %s: %s\n", | |
2641 | off, obj->path, elf_errmsg(-1)); | |
2642 | return NULL; | |
2643 | } | |
2644 | ||
2645 | return name; | |
2646 | } | |
2647 | ||
2648 | static const char *elf_sec_str(const struct bpf_object *obj, size_t off) | |
2649 | { | |
2650 | const char *name; | |
2651 | ||
2652 | name = elf_strptr(obj->efile.elf, obj->efile.shstrndx, off); | |
2653 | if (!name) { | |
2654 | pr_warn("elf: failed to get section name string at offset %zu from %s: %s\n", | |
2655 | off, obj->path, elf_errmsg(-1)); | |
2656 | return NULL; | |
2657 | } | |
2658 | ||
2659 | return name; | |
2660 | } | |
2661 | ||
2662 | static Elf_Scn *elf_sec_by_idx(const struct bpf_object *obj, size_t idx) | |
2663 | { | |
2664 | Elf_Scn *scn; | |
2665 | ||
2666 | scn = elf_getscn(obj->efile.elf, idx); | |
2667 | if (!scn) { | |
2668 | pr_warn("elf: failed to get section(%zu) from %s: %s\n", | |
2669 | idx, obj->path, elf_errmsg(-1)); | |
2670 | return NULL; | |
2671 | } | |
2672 | return scn; | |
2673 | } | |
2674 | ||
2675 | static Elf_Scn *elf_sec_by_name(const struct bpf_object *obj, const char *name) | |
2676 | { | |
2677 | Elf_Scn *scn = NULL; | |
2678 | Elf *elf = obj->efile.elf; | |
2679 | const char *sec_name; | |
2680 | ||
2681 | while ((scn = elf_nextscn(elf, scn)) != NULL) { | |
2682 | sec_name = elf_sec_name(obj, scn); | |
2683 | if (!sec_name) | |
2684 | return NULL; | |
2685 | ||
2686 | if (strcmp(sec_name, name) != 0) | |
2687 | continue; | |
2688 | ||
2689 | return scn; | |
2690 | } | |
2691 | return NULL; | |
2692 | } | |
2693 | ||
2694 | static int elf_sec_hdr(const struct bpf_object *obj, Elf_Scn *scn, GElf_Shdr *hdr) | |
2695 | { | |
2696 | if (!scn) | |
2697 | return -EINVAL; | |
2698 | ||
2699 | if (gelf_getshdr(scn, hdr) != hdr) { | |
2700 | pr_warn("elf: failed to get section(%zu) header from %s: %s\n", | |
2701 | elf_ndxscn(scn), obj->path, elf_errmsg(-1)); | |
2702 | return -EINVAL; | |
2703 | } | |
2704 | ||
2705 | return 0; | |
2706 | } | |
2707 | ||
2708 | static const char *elf_sec_name(const struct bpf_object *obj, Elf_Scn *scn) | |
2709 | { | |
2710 | const char *name; | |
2711 | GElf_Shdr sh; | |
2712 | ||
2713 | if (!scn) | |
2714 | return NULL; | |
2715 | ||
2716 | if (elf_sec_hdr(obj, scn, &sh)) | |
2717 | return NULL; | |
2718 | ||
2719 | name = elf_sec_str(obj, sh.sh_name); | |
2720 | if (!name) { | |
2721 | pr_warn("elf: failed to get section(%zu) name from %s: %s\n", | |
2722 | elf_ndxscn(scn), obj->path, elf_errmsg(-1)); | |
2723 | return NULL; | |
2724 | } | |
2725 | ||
2726 | return name; | |
2727 | } | |
2728 | ||
2729 | static Elf_Data *elf_sec_data(const struct bpf_object *obj, Elf_Scn *scn) | |
2730 | { | |
2731 | Elf_Data *data; | |
2732 | ||
2733 | if (!scn) | |
2734 | return NULL; | |
2735 | ||
2736 | data = elf_getdata(scn, 0); | |
2737 | if (!data) { | |
2738 | pr_warn("elf: failed to get section(%zu) %s data from %s: %s\n", | |
2739 | elf_ndxscn(scn), elf_sec_name(obj, scn) ?: "<?>", | |
2740 | obj->path, elf_errmsg(-1)); | |
2741 | return NULL; | |
2742 | } | |
2743 | ||
2744 | return data; | |
2745 | } | |
2746 | ||
c1122392 AN |
2747 | static int elf_sym_by_sec_off(const struct bpf_object *obj, size_t sec_idx, |
2748 | size_t off, __u32 sym_type, GElf_Sym *sym) | |
2749 | { | |
2750 | Elf_Data *symbols = obj->efile.symbols; | |
2751 | size_t n = symbols->d_size / sizeof(GElf_Sym); | |
2752 | int i; | |
2753 | ||
2754 | for (i = 0; i < n; i++) { | |
2755 | if (!gelf_getsym(symbols, i, sym)) | |
2756 | continue; | |
2757 | if (sym->st_shndx != sec_idx || sym->st_value != off) | |
2758 | continue; | |
2759 | if (GELF_ST_TYPE(sym->st_info) != sym_type) | |
2760 | continue; | |
2761 | return 0; | |
2762 | } | |
2763 | ||
2764 | return -ENOENT; | |
2765 | } | |
2766 | ||
50e09460 AN |
2767 | static bool is_sec_name_dwarf(const char *name) |
2768 | { | |
2769 | /* approximation, but the actual list is too long */ | |
2770 | return strncmp(name, ".debug_", sizeof(".debug_") - 1) == 0; | |
2771 | } | |
2772 | ||
2773 | static bool ignore_elf_section(GElf_Shdr *hdr, const char *name) | |
2774 | { | |
2775 | /* no special handling of .strtab */ | |
2776 | if (hdr->sh_type == SHT_STRTAB) | |
2777 | return true; | |
2778 | ||
2779 | /* ignore .llvm_addrsig section as well */ | |
2780 | if (hdr->sh_type == 0x6FFF4C03 /* SHT_LLVM_ADDRSIG */) | |
2781 | return true; | |
2782 | ||
2783 | /* no subprograms will lead to an empty .text section, ignore it */ | |
2784 | if (hdr->sh_type == SHT_PROGBITS && hdr->sh_size == 0 && | |
2785 | strcmp(name, ".text") == 0) | |
2786 | return true; | |
2787 | ||
2788 | /* DWARF sections */ | |
2789 | if (is_sec_name_dwarf(name)) | |
2790 | return true; | |
2791 | ||
2792 | if (strncmp(name, ".rel", sizeof(".rel") - 1) == 0) { | |
2793 | name += sizeof(".rel") - 1; | |
2794 | /* DWARF section relocations */ | |
2795 | if (is_sec_name_dwarf(name)) | |
2796 | return true; | |
2797 | ||
2798 | /* .BTF and .BTF.ext don't need relocations */ | |
2799 | if (strcmp(name, BTF_ELF_SEC) == 0 || | |
2800 | strcmp(name, BTF_EXT_ELF_SEC) == 0) | |
2801 | return true; | |
2802 | } | |
2803 | ||
2804 | return false; | |
2805 | } | |
2806 | ||
db2b8b06 AN |
2807 | static int cmp_progs(const void *_a, const void *_b) |
2808 | { | |
2809 | const struct bpf_program *a = _a; | |
2810 | const struct bpf_program *b = _b; | |
2811 | ||
2812 | if (a->sec_idx != b->sec_idx) | |
2813 | return a->sec_idx < b->sec_idx ? -1 : 1; | |
2814 | ||
2815 | /* sec_insn_off can't be the same within the section */ | |
2816 | return a->sec_insn_off < b->sec_insn_off ? -1 : 1; | |
2817 | } | |
2818 | ||
0d13bfce | 2819 | static int bpf_object__elf_collect(struct bpf_object *obj) |
29603665 WN |
2820 | { |
2821 | Elf *elf = obj->efile.elf; | |
f0187f0b | 2822 | Elf_Data *btf_ext_data = NULL; |
1713d68b | 2823 | Elf_Data *btf_data = NULL; |
666810e8 | 2824 | int idx = 0, err = 0; |
0201c575 AN |
2825 | const char *name; |
2826 | Elf_Data *data; | |
2827 | Elf_Scn *scn; | |
2828 | GElf_Shdr sh; | |
29603665 | 2829 | |
0201c575 AN |
2830 | /* a bunch of ELF parsing functionality depends on processing symbols, |
2831 | * so do the first pass and find the symbol table | |
2832 | */ | |
2833 | scn = NULL; | |
29603665 | 2834 | while ((scn = elf_nextscn(elf, scn)) != NULL) { |
0201c575 AN |
2835 | if (elf_sec_hdr(obj, scn, &sh)) |
2836 | return -LIBBPF_ERRNO__FORMAT; | |
2837 | ||
2838 | if (sh.sh_type == SHT_SYMTAB) { | |
2839 | if (obj->efile.symbols) { | |
2840 | pr_warn("elf: multiple symbol tables in %s\n", obj->path); | |
2841 | return -LIBBPF_ERRNO__FORMAT; | |
2842 | } | |
29603665 | 2843 | |
0201c575 AN |
2844 | data = elf_sec_data(obj, scn); |
2845 | if (!data) | |
2846 | return -LIBBPF_ERRNO__FORMAT; | |
2847 | ||
2848 | obj->efile.symbols = data; | |
2849 | obj->efile.symbols_shndx = elf_ndxscn(scn); | |
2850 | obj->efile.strtabidx = sh.sh_link; | |
2851 | } | |
2852 | } | |
2853 | ||
2854 | scn = NULL; | |
2855 | while ((scn = elf_nextscn(elf, scn)) != NULL) { | |
29603665 | 2856 | idx++; |
88a82120 AN |
2857 | |
2858 | if (elf_sec_hdr(obj, scn, &sh)) | |
01b29d1d | 2859 | return -LIBBPF_ERRNO__FORMAT; |
29603665 | 2860 | |
88a82120 AN |
2861 | name = elf_sec_str(obj, sh.sh_name); |
2862 | if (!name) | |
01b29d1d | 2863 | return -LIBBPF_ERRNO__FORMAT; |
29603665 | 2864 | |
50e09460 AN |
2865 | if (ignore_elf_section(&sh, name)) |
2866 | continue; | |
2867 | ||
88a82120 AN |
2868 | data = elf_sec_data(obj, scn); |
2869 | if (!data) | |
01b29d1d | 2870 | return -LIBBPF_ERRNO__FORMAT; |
88a82120 AN |
2871 | |
2872 | pr_debug("elf: section(%d) %s, size %ld, link %d, flags %lx, type=%d\n", | |
077c066a | 2873 | idx, name, (unsigned long)data->d_size, |
29603665 WN |
2874 | (int)sh.sh_link, (unsigned long)sh.sh_flags, |
2875 | (int)sh.sh_type); | |
cb1e5e96 | 2876 | |
1713d68b | 2877 | if (strcmp(name, "license") == 0) { |
88a82120 | 2878 | err = bpf_object__init_license(obj, data->d_buf, data->d_size); |
01b29d1d AN |
2879 | if (err) |
2880 | return err; | |
1713d68b | 2881 | } else if (strcmp(name, "version") == 0) { |
88a82120 | 2882 | err = bpf_object__init_kversion(obj, data->d_buf, data->d_size); |
54b8625c JF |
2883 | if (err) |
2884 | return err; | |
1713d68b | 2885 | } else if (strcmp(name, "maps") == 0) { |
666810e8 | 2886 | obj->efile.maps_shndx = idx; |
abd29c93 AN |
2887 | } else if (strcmp(name, MAPS_ELF_SEC) == 0) { |
2888 | obj->efile.btf_maps_shndx = idx; | |
1713d68b DB |
2889 | } else if (strcmp(name, BTF_ELF_SEC) == 0) { |
2890 | btf_data = data; | |
2993e051 | 2891 | } else if (strcmp(name, BTF_EXT_ELF_SEC) == 0) { |
f0187f0b | 2892 | btf_ext_data = data; |
8a138aed | 2893 | } else if (sh.sh_type == SHT_SYMTAB) { |
0201c575 | 2894 | /* already processed during the first pass above */ |
f8c7a4d4 JS |
2895 | } else if (sh.sh_type == SHT_PROGBITS && data->d_size > 0) { |
2896 | if (sh.sh_flags & SHF_EXECINSTR) { | |
2897 | if (strcmp(name, ".text") == 0) | |
2898 | obj->efile.text_shndx = idx; | |
c1122392 | 2899 | err = bpf_object__add_programs(obj, data, name, idx); |
88a82120 | 2900 | if (err) |
01b29d1d | 2901 | return err; |
ac9d1389 | 2902 | } else if (strcmp(name, DATA_SEC) == 0) { |
d859900c DB |
2903 | obj->efile.data = data; |
2904 | obj->efile.data_shndx = idx; | |
ac9d1389 | 2905 | } else if (strcmp(name, RODATA_SEC) == 0) { |
d859900c DB |
2906 | obj->efile.rodata = data; |
2907 | obj->efile.rodata_shndx = idx; | |
590a0088 MKL |
2908 | } else if (strcmp(name, STRUCT_OPS_SEC) == 0) { |
2909 | obj->efile.st_ops_data = data; | |
2910 | obj->efile.st_ops_shndx = idx; | |
d859900c | 2911 | } else { |
50e09460 AN |
2912 | pr_info("elf: skipping unrecognized data section(%d) %s\n", |
2913 | idx, name); | |
a5b8bd47 | 2914 | } |
b62f06e8 | 2915 | } else if (sh.sh_type == SHT_REL) { |
1f8e2bcb AN |
2916 | int nr_sects = obj->efile.nr_reloc_sects; |
2917 | void *sects = obj->efile.reloc_sects; | |
e3d91b0c JDB |
2918 | int sec = sh.sh_info; /* points to other section */ |
2919 | ||
2920 | /* Only do relo for section with exec instructions */ | |
590a0088 | 2921 | if (!section_have_execinstr(obj, sec) && |
646f02ff AN |
2922 | strcmp(name, ".rel" STRUCT_OPS_SEC) && |
2923 | strcmp(name, ".rel" MAPS_ELF_SEC)) { | |
50e09460 AN |
2924 | pr_info("elf: skipping relo section(%d) %s for section(%d) %s\n", |
2925 | idx, name, sec, | |
2926 | elf_sec_name(obj, elf_sec_by_idx(obj, sec)) ?: "<?>"); | |
e3d91b0c JDB |
2927 | continue; |
2928 | } | |
b62f06e8 | 2929 | |
029258d7 AN |
2930 | sects = libbpf_reallocarray(sects, nr_sects + 1, |
2931 | sizeof(*obj->efile.reloc_sects)); | |
88a82120 | 2932 | if (!sects) |
01b29d1d | 2933 | return -ENOMEM; |
b62f06e8 | 2934 | |
1f8e2bcb AN |
2935 | obj->efile.reloc_sects = sects; |
2936 | obj->efile.nr_reloc_sects++; | |
b62f06e8 | 2937 | |
1f8e2bcb AN |
2938 | obj->efile.reloc_sects[nr_sects].shdr = sh; |
2939 | obj->efile.reloc_sects[nr_sects].data = data; | |
88a82120 | 2940 | } else if (sh.sh_type == SHT_NOBITS && strcmp(name, BSS_SEC) == 0) { |
d859900c DB |
2941 | obj->efile.bss = data; |
2942 | obj->efile.bss_shndx = idx; | |
077c066a | 2943 | } else { |
2e80be60 AN |
2944 | pr_info("elf: skipping section(%d) %s (size %zu)\n", idx, name, |
2945 | (size_t)sh.sh_size); | |
bec7d68c | 2946 | } |
29603665 | 2947 | } |
561bbcca | 2948 | |
d3a3aa0c | 2949 | if (!obj->efile.strtabidx || obj->efile.strtabidx > idx) { |
88a82120 | 2950 | pr_warn("elf: symbol strings section missing or invalid in %s\n", obj->path); |
f102154d | 2951 | return -LIBBPF_ERRNO__FORMAT; |
77ba9a5b | 2952 | } |
db2b8b06 AN |
2953 | |
2954 | /* sort BPF programs by section name and in-section instruction offset | |
2955 | * for faster search */ | |
2956 | qsort(obj->programs, obj->nr_programs, sizeof(*obj->programs), cmp_progs); | |
2957 | ||
0d13bfce | 2958 | return bpf_object__init_btf(obj, btf_data, btf_ext_data); |
29603665 WN |
2959 | } |
2960 | ||
166750bc AN |
2961 | static bool sym_is_extern(const GElf_Sym *sym) |
2962 | { | |
2963 | int bind = GELF_ST_BIND(sym->st_info); | |
2964 | /* externs are symbols w/ type=NOTYPE, bind=GLOBAL|WEAK, section=UND */ | |
2965 | return sym->st_shndx == SHN_UNDEF && | |
2966 | (bind == STB_GLOBAL || bind == STB_WEAK) && | |
2967 | GELF_ST_TYPE(sym->st_info) == STT_NOTYPE; | |
2968 | } | |
2969 | ||
2970 | static int find_extern_btf_id(const struct btf *btf, const char *ext_name) | |
2971 | { | |
2972 | const struct btf_type *t; | |
2973 | const char *var_name; | |
2974 | int i, n; | |
2975 | ||
2976 | if (!btf) | |
2977 | return -ESRCH; | |
2978 | ||
2979 | n = btf__get_nr_types(btf); | |
2980 | for (i = 1; i <= n; i++) { | |
2981 | t = btf__type_by_id(btf, i); | |
2982 | ||
2983 | if (!btf_is_var(t)) | |
2984 | continue; | |
2985 | ||
2986 | var_name = btf__name_by_offset(btf, t->name_off); | |
2987 | if (strcmp(var_name, ext_name)) | |
2988 | continue; | |
2989 | ||
2990 | if (btf_var(t)->linkage != BTF_VAR_GLOBAL_EXTERN) | |
2991 | return -EINVAL; | |
2992 | ||
2993 | return i; | |
2994 | } | |
2995 | ||
2996 | return -ENOENT; | |
2997 | } | |
2998 | ||
2e33efe3 AN |
2999 | static int find_extern_sec_btf_id(struct btf *btf, int ext_btf_id) { |
3000 | const struct btf_var_secinfo *vs; | |
3001 | const struct btf_type *t; | |
3002 | int i, j, n; | |
3003 | ||
3004 | if (!btf) | |
3005 | return -ESRCH; | |
3006 | ||
3007 | n = btf__get_nr_types(btf); | |
3008 | for (i = 1; i <= n; i++) { | |
3009 | t = btf__type_by_id(btf, i); | |
3010 | ||
3011 | if (!btf_is_datasec(t)) | |
3012 | continue; | |
3013 | ||
3014 | vs = btf_var_secinfos(t); | |
3015 | for (j = 0; j < btf_vlen(t); j++, vs++) { | |
3016 | if (vs->type == ext_btf_id) | |
3017 | return i; | |
3018 | } | |
3019 | } | |
3020 | ||
3021 | return -ENOENT; | |
3022 | } | |
3023 | ||
3024 | static enum kcfg_type find_kcfg_type(const struct btf *btf, int id, | |
3025 | bool *is_signed) | |
166750bc AN |
3026 | { |
3027 | const struct btf_type *t; | |
3028 | const char *name; | |
3029 | ||
3030 | t = skip_mods_and_typedefs(btf, id, NULL); | |
3031 | name = btf__name_by_offset(btf, t->name_off); | |
3032 | ||
3033 | if (is_signed) | |
3034 | *is_signed = false; | |
3035 | switch (btf_kind(t)) { | |
3036 | case BTF_KIND_INT: { | |
3037 | int enc = btf_int_encoding(t); | |
3038 | ||
3039 | if (enc & BTF_INT_BOOL) | |
2e33efe3 | 3040 | return t->size == 1 ? KCFG_BOOL : KCFG_UNKNOWN; |
166750bc AN |
3041 | if (is_signed) |
3042 | *is_signed = enc & BTF_INT_SIGNED; | |
3043 | if (t->size == 1) | |
2e33efe3 | 3044 | return KCFG_CHAR; |
166750bc | 3045 | if (t->size < 1 || t->size > 8 || (t->size & (t->size - 1))) |
2e33efe3 AN |
3046 | return KCFG_UNKNOWN; |
3047 | return KCFG_INT; | |
166750bc AN |
3048 | } |
3049 | case BTF_KIND_ENUM: | |
3050 | if (t->size != 4) | |
2e33efe3 | 3051 | return KCFG_UNKNOWN; |
166750bc | 3052 | if (strcmp(name, "libbpf_tristate")) |
2e33efe3 AN |
3053 | return KCFG_UNKNOWN; |
3054 | return KCFG_TRISTATE; | |
166750bc AN |
3055 | case BTF_KIND_ARRAY: |
3056 | if (btf_array(t)->nelems == 0) | |
2e33efe3 AN |
3057 | return KCFG_UNKNOWN; |
3058 | if (find_kcfg_type(btf, btf_array(t)->type, NULL) != KCFG_CHAR) | |
3059 | return KCFG_UNKNOWN; | |
3060 | return KCFG_CHAR_ARR; | |
166750bc | 3061 | default: |
2e33efe3 | 3062 | return KCFG_UNKNOWN; |
166750bc AN |
3063 | } |
3064 | } | |
3065 | ||
3066 | static int cmp_externs(const void *_a, const void *_b) | |
3067 | { | |
3068 | const struct extern_desc *a = _a; | |
3069 | const struct extern_desc *b = _b; | |
3070 | ||
2e33efe3 AN |
3071 | if (a->type != b->type) |
3072 | return a->type < b->type ? -1 : 1; | |
3073 | ||
3074 | if (a->type == EXT_KCFG) { | |
3075 | /* descending order by alignment requirements */ | |
3076 | if (a->kcfg.align != b->kcfg.align) | |
3077 | return a->kcfg.align > b->kcfg.align ? -1 : 1; | |
3078 | /* ascending order by size, within same alignment class */ | |
3079 | if (a->kcfg.sz != b->kcfg.sz) | |
3080 | return a->kcfg.sz < b->kcfg.sz ? -1 : 1; | |
3081 | } | |
3082 | ||
166750bc AN |
3083 | /* resolve ties by name */ |
3084 | return strcmp(a->name, b->name); | |
3085 | } | |
3086 | ||
1c0c7074 AN |
3087 | static int find_int_btf_id(const struct btf *btf) |
3088 | { | |
3089 | const struct btf_type *t; | |
3090 | int i, n; | |
3091 | ||
3092 | n = btf__get_nr_types(btf); | |
3093 | for (i = 1; i <= n; i++) { | |
3094 | t = btf__type_by_id(btf, i); | |
3095 | ||
3096 | if (btf_is_int(t) && btf_int_bits(t) == 32) | |
3097 | return i; | |
3098 | } | |
3099 | ||
3100 | return 0; | |
3101 | } | |
3102 | ||
166750bc AN |
3103 | static int bpf_object__collect_externs(struct bpf_object *obj) |
3104 | { | |
1c0c7074 | 3105 | struct btf_type *sec, *kcfg_sec = NULL, *ksym_sec = NULL; |
166750bc AN |
3106 | const struct btf_type *t; |
3107 | struct extern_desc *ext; | |
2e33efe3 AN |
3108 | int i, n, off; |
3109 | const char *ext_name, *sec_name; | |
166750bc AN |
3110 | Elf_Scn *scn; |
3111 | GElf_Shdr sh; | |
3112 | ||
3113 | if (!obj->efile.symbols) | |
3114 | return 0; | |
3115 | ||
88a82120 AN |
3116 | scn = elf_sec_by_idx(obj, obj->efile.symbols_shndx); |
3117 | if (elf_sec_hdr(obj, scn, &sh)) | |
166750bc | 3118 | return -LIBBPF_ERRNO__FORMAT; |
166750bc | 3119 | |
88a82120 | 3120 | n = sh.sh_size / sh.sh_entsize; |
166750bc | 3121 | pr_debug("looking for externs among %d symbols...\n", n); |
88a82120 | 3122 | |
166750bc AN |
3123 | for (i = 0; i < n; i++) { |
3124 | GElf_Sym sym; | |
3125 | ||
3126 | if (!gelf_getsym(obj->efile.symbols, i, &sym)) | |
3127 | return -LIBBPF_ERRNO__FORMAT; | |
3128 | if (!sym_is_extern(&sym)) | |
3129 | continue; | |
88a82120 | 3130 | ext_name = elf_sym_str(obj, sym.st_name); |
166750bc AN |
3131 | if (!ext_name || !ext_name[0]) |
3132 | continue; | |
3133 | ||
3134 | ext = obj->externs; | |
029258d7 | 3135 | ext = libbpf_reallocarray(ext, obj->nr_extern + 1, sizeof(*ext)); |
166750bc AN |
3136 | if (!ext) |
3137 | return -ENOMEM; | |
3138 | obj->externs = ext; | |
3139 | ext = &ext[obj->nr_extern]; | |
3140 | memset(ext, 0, sizeof(*ext)); | |
3141 | obj->nr_extern++; | |
3142 | ||
3143 | ext->btf_id = find_extern_btf_id(obj->btf, ext_name); | |
3144 | if (ext->btf_id <= 0) { | |
3145 | pr_warn("failed to find BTF for extern '%s': %d\n", | |
3146 | ext_name, ext->btf_id); | |
3147 | return ext->btf_id; | |
3148 | } | |
3149 | t = btf__type_by_id(obj->btf, ext->btf_id); | |
3150 | ext->name = btf__name_by_offset(obj->btf, t->name_off); | |
3151 | ext->sym_idx = i; | |
3152 | ext->is_weak = GELF_ST_BIND(sym.st_info) == STB_WEAK; | |
2e33efe3 AN |
3153 | |
3154 | ext->sec_btf_id = find_extern_sec_btf_id(obj->btf, ext->btf_id); | |
3155 | if (ext->sec_btf_id <= 0) { | |
3156 | pr_warn("failed to find BTF for extern '%s' [%d] section: %d\n", | |
3157 | ext_name, ext->btf_id, ext->sec_btf_id); | |
3158 | return ext->sec_btf_id; | |
166750bc | 3159 | } |
2e33efe3 AN |
3160 | sec = (void *)btf__type_by_id(obj->btf, ext->sec_btf_id); |
3161 | sec_name = btf__name_by_offset(obj->btf, sec->name_off); | |
3162 | ||
3163 | if (strcmp(sec_name, KCONFIG_SEC) == 0) { | |
3164 | kcfg_sec = sec; | |
3165 | ext->type = EXT_KCFG; | |
3166 | ext->kcfg.sz = btf__resolve_size(obj->btf, t->type); | |
3167 | if (ext->kcfg.sz <= 0) { | |
3168 | pr_warn("failed to resolve size of extern (kcfg) '%s': %d\n", | |
3169 | ext_name, ext->kcfg.sz); | |
3170 | return ext->kcfg.sz; | |
3171 | } | |
3172 | ext->kcfg.align = btf__align_of(obj->btf, t->type); | |
3173 | if (ext->kcfg.align <= 0) { | |
3174 | pr_warn("failed to determine alignment of extern (kcfg) '%s': %d\n", | |
3175 | ext_name, ext->kcfg.align); | |
3176 | return -EINVAL; | |
3177 | } | |
3178 | ext->kcfg.type = find_kcfg_type(obj->btf, t->type, | |
3179 | &ext->kcfg.is_signed); | |
3180 | if (ext->kcfg.type == KCFG_UNKNOWN) { | |
3181 | pr_warn("extern (kcfg) '%s' type is unsupported\n", ext_name); | |
3182 | return -ENOTSUP; | |
3183 | } | |
1c0c7074 | 3184 | } else if (strcmp(sec_name, KSYMS_SEC) == 0) { |
1c0c7074 AN |
3185 | ksym_sec = sec; |
3186 | ext->type = EXT_KSYM; | |
d370bbe1 HL |
3187 | skip_mods_and_typedefs(obj->btf, t->type, |
3188 | &ext->ksym.type_id); | |
2e33efe3 AN |
3189 | } else { |
3190 | pr_warn("unrecognized extern section '%s'\n", sec_name); | |
166750bc AN |
3191 | return -ENOTSUP; |
3192 | } | |
3193 | } | |
3194 | pr_debug("collected %d externs total\n", obj->nr_extern); | |
3195 | ||
3196 | if (!obj->nr_extern) | |
3197 | return 0; | |
3198 | ||
2e33efe3 | 3199 | /* sort externs by type, for kcfg ones also by (align, size, name) */ |
166750bc | 3200 | qsort(obj->externs, obj->nr_extern, sizeof(*ext), cmp_externs); |
166750bc | 3201 | |
1c0c7074 AN |
3202 | /* for .ksyms section, we need to turn all externs into allocated |
3203 | * variables in BTF to pass kernel verification; we do this by | |
3204 | * pretending that each extern is a 8-byte variable | |
3205 | */ | |
3206 | if (ksym_sec) { | |
3207 | /* find existing 4-byte integer type in BTF to use for fake | |
3208 | * extern variables in DATASEC | |
3209 | */ | |
3210 | int int_btf_id = find_int_btf_id(obj->btf); | |
3211 | ||
3212 | for (i = 0; i < obj->nr_extern; i++) { | |
3213 | ext = &obj->externs[i]; | |
3214 | if (ext->type != EXT_KSYM) | |
3215 | continue; | |
3216 | pr_debug("extern (ksym) #%d: symbol %d, name %s\n", | |
3217 | i, ext->sym_idx, ext->name); | |
3218 | } | |
3219 | ||
3220 | sec = ksym_sec; | |
3221 | n = btf_vlen(sec); | |
3222 | for (i = 0, off = 0; i < n; i++, off += sizeof(int)) { | |
3223 | struct btf_var_secinfo *vs = btf_var_secinfos(sec) + i; | |
3224 | struct btf_type *vt; | |
3225 | ||
3226 | vt = (void *)btf__type_by_id(obj->btf, vs->type); | |
3227 | ext_name = btf__name_by_offset(obj->btf, vt->name_off); | |
3228 | ext = find_extern_by_name(obj, ext_name); | |
3229 | if (!ext) { | |
3230 | pr_warn("failed to find extern definition for BTF var '%s'\n", | |
3231 | ext_name); | |
3232 | return -ESRCH; | |
3233 | } | |
3234 | btf_var(vt)->linkage = BTF_VAR_GLOBAL_ALLOCATED; | |
3235 | vt->type = int_btf_id; | |
3236 | vs->offset = off; | |
3237 | vs->size = sizeof(int); | |
3238 | } | |
3239 | sec->size = off; | |
3240 | } | |
3241 | ||
2e33efe3 AN |
3242 | if (kcfg_sec) { |
3243 | sec = kcfg_sec; | |
3244 | /* for kcfg externs calculate their offsets within a .kconfig map */ | |
3245 | off = 0; | |
3246 | for (i = 0; i < obj->nr_extern; i++) { | |
3247 | ext = &obj->externs[i]; | |
3248 | if (ext->type != EXT_KCFG) | |
3249 | continue; | |
166750bc | 3250 | |
2e33efe3 AN |
3251 | ext->kcfg.data_off = roundup(off, ext->kcfg.align); |
3252 | off = ext->kcfg.data_off + ext->kcfg.sz; | |
1c0c7074 | 3253 | pr_debug("extern (kcfg) #%d: symbol %d, off %u, name %s\n", |
2e33efe3 AN |
3254 | i, ext->sym_idx, ext->kcfg.data_off, ext->name); |
3255 | } | |
3256 | sec->size = off; | |
3257 | n = btf_vlen(sec); | |
3258 | for (i = 0; i < n; i++) { | |
3259 | struct btf_var_secinfo *vs = btf_var_secinfos(sec) + i; | |
3260 | ||
3261 | t = btf__type_by_id(obj->btf, vs->type); | |
3262 | ext_name = btf__name_by_offset(obj->btf, t->name_off); | |
3263 | ext = find_extern_by_name(obj, ext_name); | |
3264 | if (!ext) { | |
3265 | pr_warn("failed to find extern definition for BTF var '%s'\n", | |
3266 | ext_name); | |
3267 | return -ESRCH; | |
3268 | } | |
3269 | btf_var(t)->linkage = BTF_VAR_GLOBAL_ALLOCATED; | |
3270 | vs->offset = ext->kcfg.data_off; | |
166750bc | 3271 | } |
166750bc | 3272 | } |
166750bc AN |
3273 | return 0; |
3274 | } | |
3275 | ||
6d4b198b | 3276 | struct bpf_program * |
a324aae3 AN |
3277 | bpf_object__find_program_by_title(const struct bpf_object *obj, |
3278 | const char *title) | |
6d4b198b JK |
3279 | { |
3280 | struct bpf_program *pos; | |
3281 | ||
3282 | bpf_object__for_each_program(pos, obj) { | |
52109584 | 3283 | if (pos->sec_name && !strcmp(pos->sec_name, title)) |
6d4b198b JK |
3284 | return pos; |
3285 | } | |
3286 | return NULL; | |
3287 | } | |
3288 | ||
c3c55696 AN |
3289 | static bool prog_is_subprog(const struct bpf_object *obj, |
3290 | const struct bpf_program *prog) | |
3291 | { | |
197afc63 AN |
3292 | /* For legacy reasons, libbpf supports an entry-point BPF programs |
3293 | * without SEC() attribute, i.e., those in the .text section. But if | |
3294 | * there are 2 or more such programs in the .text section, they all | |
3295 | * must be subprograms called from entry-point BPF programs in | |
3296 | * designated SEC()'tions, otherwise there is no way to distinguish | |
3297 | * which of those programs should be loaded vs which are a subprogram. | |
3298 | * Similarly, if there is a function/program in .text and at least one | |
3299 | * other BPF program with custom SEC() attribute, then we just assume | |
3300 | * .text programs are subprograms (even if they are not called from | |
3301 | * other programs), because libbpf never explicitly supported mixing | |
3302 | * SEC()-designated BPF programs and .text entry-point BPF programs. | |
3303 | */ | |
3304 | return prog->sec_idx == obj->efile.text_shndx && obj->nr_programs > 1; | |
c3c55696 AN |
3305 | } |
3306 | ||
01af3bf0 AN |
3307 | struct bpf_program * |
3308 | bpf_object__find_program_by_name(const struct bpf_object *obj, | |
3309 | const char *name) | |
3310 | { | |
3311 | struct bpf_program *prog; | |
3312 | ||
3313 | bpf_object__for_each_program(prog, obj) { | |
c3c55696 AN |
3314 | if (prog_is_subprog(obj, prog)) |
3315 | continue; | |
01af3bf0 AN |
3316 | if (!strcmp(prog->name, name)) |
3317 | return prog; | |
3318 | } | |
3319 | return NULL; | |
3320 | } | |
3321 | ||
d859900c DB |
3322 | static bool bpf_object__shndx_is_data(const struct bpf_object *obj, |
3323 | int shndx) | |
3324 | { | |
3325 | return shndx == obj->efile.data_shndx || | |
3326 | shndx == obj->efile.bss_shndx || | |
3327 | shndx == obj->efile.rodata_shndx; | |
3328 | } | |
3329 | ||
3330 | static bool bpf_object__shndx_is_maps(const struct bpf_object *obj, | |
3331 | int shndx) | |
3332 | { | |
abd29c93 AN |
3333 | return shndx == obj->efile.maps_shndx || |
3334 | shndx == obj->efile.btf_maps_shndx; | |
d859900c DB |
3335 | } |
3336 | ||
d859900c DB |
3337 | static enum libbpf_map_type |
3338 | bpf_object__section_to_libbpf_map_type(const struct bpf_object *obj, int shndx) | |
3339 | { | |
3340 | if (shndx == obj->efile.data_shndx) | |
3341 | return LIBBPF_MAP_DATA; | |
3342 | else if (shndx == obj->efile.bss_shndx) | |
3343 | return LIBBPF_MAP_BSS; | |
3344 | else if (shndx == obj->efile.rodata_shndx) | |
3345 | return LIBBPF_MAP_RODATA; | |
166750bc | 3346 | else if (shndx == obj->efile.symbols_shndx) |
81bfdd08 | 3347 | return LIBBPF_MAP_KCONFIG; |
d859900c DB |
3348 | else |
3349 | return LIBBPF_MAP_UNSPEC; | |
3350 | } | |
3351 | ||
1f8e2bcb AN |
3352 | static int bpf_program__record_reloc(struct bpf_program *prog, |
3353 | struct reloc_desc *reloc_desc, | |
9c0f8cbd | 3354 | __u32 insn_idx, const char *sym_name, |
1f8e2bcb AN |
3355 | const GElf_Sym *sym, const GElf_Rel *rel) |
3356 | { | |
3357 | struct bpf_insn *insn = &prog->insns[insn_idx]; | |
3358 | size_t map_idx, nr_maps = prog->obj->nr_maps; | |
3359 | struct bpf_object *obj = prog->obj; | |
3360 | __u32 shdr_idx = sym->st_shndx; | |
3361 | enum libbpf_map_type type; | |
9c0f8cbd | 3362 | const char *sym_sec_name; |
1f8e2bcb AN |
3363 | struct bpf_map *map; |
3364 | ||
c3c55696 AN |
3365 | reloc_desc->processed = false; |
3366 | ||
1f8e2bcb AN |
3367 | /* sub-program call relocation */ |
3368 | if (insn->code == (BPF_JMP | BPF_CALL)) { | |
3369 | if (insn->src_reg != BPF_PSEUDO_CALL) { | |
9c0f8cbd | 3370 | pr_warn("prog '%s': incorrect bpf_call opcode\n", prog->name); |
1f8e2bcb AN |
3371 | return -LIBBPF_ERRNO__RELOC; |
3372 | } | |
3373 | /* text_shndx can be 0, if no default "main" program exists */ | |
3374 | if (!shdr_idx || shdr_idx != obj->efile.text_shndx) { | |
9c0f8cbd AN |
3375 | sym_sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, shdr_idx)); |
3376 | pr_warn("prog '%s': bad call relo against '%s' in section '%s'\n", | |
3377 | prog->name, sym_name, sym_sec_name); | |
1f8e2bcb AN |
3378 | return -LIBBPF_ERRNO__RELOC; |
3379 | } | |
9c0f8cbd AN |
3380 | if (sym->st_value % BPF_INSN_SZ) { |
3381 | pr_warn("prog '%s': bad call relo against '%s' at offset %zu\n", | |
3382 | prog->name, sym_name, (size_t)sym->st_value); | |
1f8e2bcb AN |
3383 | return -LIBBPF_ERRNO__RELOC; |
3384 | } | |
3385 | reloc_desc->type = RELO_CALL; | |
3386 | reloc_desc->insn_idx = insn_idx; | |
53f8dd43 | 3387 | reloc_desc->sym_off = sym->st_value; |
1f8e2bcb AN |
3388 | return 0; |
3389 | } | |
3390 | ||
3391 | if (insn->code != (BPF_LD | BPF_IMM | BPF_DW)) { | |
9c0f8cbd AN |
3392 | pr_warn("prog '%s': invalid relo against '%s' for insns[%d].code 0x%x\n", |
3393 | prog->name, sym_name, insn_idx, insn->code); | |
1f8e2bcb AN |
3394 | return -LIBBPF_ERRNO__RELOC; |
3395 | } | |
166750bc AN |
3396 | |
3397 | if (sym_is_extern(sym)) { | |
3398 | int sym_idx = GELF_R_SYM(rel->r_info); | |
3399 | int i, n = obj->nr_extern; | |
3400 | struct extern_desc *ext; | |
3401 | ||
3402 | for (i = 0; i < n; i++) { | |
3403 | ext = &obj->externs[i]; | |
3404 | if (ext->sym_idx == sym_idx) | |
3405 | break; | |
3406 | } | |
3407 | if (i >= n) { | |
9c0f8cbd AN |
3408 | pr_warn("prog '%s': extern relo failed to find extern for '%s' (%d)\n", |
3409 | prog->name, sym_name, sym_idx); | |
166750bc AN |
3410 | return -LIBBPF_ERRNO__RELOC; |
3411 | } | |
9c0f8cbd AN |
3412 | pr_debug("prog '%s': found extern #%d '%s' (sym %d) for insn #%u\n", |
3413 | prog->name, i, ext->name, ext->sym_idx, insn_idx); | |
166750bc AN |
3414 | reloc_desc->type = RELO_EXTERN; |
3415 | reloc_desc->insn_idx = insn_idx; | |
2e33efe3 | 3416 | reloc_desc->sym_off = i; /* sym_off stores extern index */ |
166750bc AN |
3417 | return 0; |
3418 | } | |
3419 | ||
1f8e2bcb | 3420 | if (!shdr_idx || shdr_idx >= SHN_LORESERVE) { |
9c0f8cbd AN |
3421 | pr_warn("prog '%s': invalid relo against '%s' in special section 0x%x; forgot to initialize global var?..\n", |
3422 | prog->name, sym_name, shdr_idx); | |
1f8e2bcb AN |
3423 | return -LIBBPF_ERRNO__RELOC; |
3424 | } | |
3425 | ||
3426 | type = bpf_object__section_to_libbpf_map_type(obj, shdr_idx); | |
9c0f8cbd | 3427 | sym_sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, shdr_idx)); |
1f8e2bcb AN |
3428 | |
3429 | /* generic map reference relocation */ | |
3430 | if (type == LIBBPF_MAP_UNSPEC) { | |
3431 | if (!bpf_object__shndx_is_maps(obj, shdr_idx)) { | |
9c0f8cbd AN |
3432 | pr_warn("prog '%s': bad map relo against '%s' in section '%s'\n", |
3433 | prog->name, sym_name, sym_sec_name); | |
1f8e2bcb AN |
3434 | return -LIBBPF_ERRNO__RELOC; |
3435 | } | |
3436 | for (map_idx = 0; map_idx < nr_maps; map_idx++) { | |
3437 | map = &obj->maps[map_idx]; | |
3438 | if (map->libbpf_type != type || | |
3439 | map->sec_idx != sym->st_shndx || | |
3440 | map->sec_offset != sym->st_value) | |
3441 | continue; | |
9c0f8cbd AN |
3442 | pr_debug("prog '%s': found map %zd (%s, sec %d, off %zu) for insn #%u\n", |
3443 | prog->name, map_idx, map->name, map->sec_idx, | |
1f8e2bcb AN |
3444 | map->sec_offset, insn_idx); |
3445 | break; | |
3446 | } | |
3447 | if (map_idx >= nr_maps) { | |
9c0f8cbd AN |
3448 | pr_warn("prog '%s': map relo failed to find map for section '%s', off %zu\n", |
3449 | prog->name, sym_sec_name, (size_t)sym->st_value); | |
1f8e2bcb AN |
3450 | return -LIBBPF_ERRNO__RELOC; |
3451 | } | |
3452 | reloc_desc->type = RELO_LD64; | |
3453 | reloc_desc->insn_idx = insn_idx; | |
3454 | reloc_desc->map_idx = map_idx; | |
53f8dd43 | 3455 | reloc_desc->sym_off = 0; /* sym->st_value determines map_idx */ |
1f8e2bcb AN |
3456 | return 0; |
3457 | } | |
3458 | ||
3459 | /* global data map relocation */ | |
3460 | if (!bpf_object__shndx_is_data(obj, shdr_idx)) { | |
9c0f8cbd AN |
3461 | pr_warn("prog '%s': bad data relo against section '%s'\n", |
3462 | prog->name, sym_sec_name); | |
1f8e2bcb | 3463 | return -LIBBPF_ERRNO__RELOC; |
1f8e2bcb | 3464 | } |
1f8e2bcb AN |
3465 | for (map_idx = 0; map_idx < nr_maps; map_idx++) { |
3466 | map = &obj->maps[map_idx]; | |
3467 | if (map->libbpf_type != type) | |
3468 | continue; | |
9c0f8cbd AN |
3469 | pr_debug("prog '%s': found data map %zd (%s, sec %d, off %zu) for insn %u\n", |
3470 | prog->name, map_idx, map->name, map->sec_idx, | |
3471 | map->sec_offset, insn_idx); | |
1f8e2bcb AN |
3472 | break; |
3473 | } | |
3474 | if (map_idx >= nr_maps) { | |
9c0f8cbd AN |
3475 | pr_warn("prog '%s': data relo failed to find map for section '%s'\n", |
3476 | prog->name, sym_sec_name); | |
1f8e2bcb AN |
3477 | return -LIBBPF_ERRNO__RELOC; |
3478 | } | |
3479 | ||
3480 | reloc_desc->type = RELO_DATA; | |
3481 | reloc_desc->insn_idx = insn_idx; | |
3482 | reloc_desc->map_idx = map_idx; | |
53f8dd43 | 3483 | reloc_desc->sym_off = sym->st_value; |
1f8e2bcb AN |
3484 | return 0; |
3485 | } | |
3486 | ||
db2b8b06 AN |
3487 | static bool prog_contains_insn(const struct bpf_program *prog, size_t insn_idx) |
3488 | { | |
3489 | return insn_idx >= prog->sec_insn_off && | |
3490 | insn_idx < prog->sec_insn_off + prog->sec_insn_cnt; | |
3491 | } | |
3492 | ||
3493 | static struct bpf_program *find_prog_by_sec_insn(const struct bpf_object *obj, | |
3494 | size_t sec_idx, size_t insn_idx) | |
3495 | { | |
3496 | int l = 0, r = obj->nr_programs - 1, m; | |
3497 | struct bpf_program *prog; | |
3498 | ||
3499 | while (l < r) { | |
3500 | m = l + (r - l + 1) / 2; | |
3501 | prog = &obj->programs[m]; | |
3502 | ||
3503 | if (prog->sec_idx < sec_idx || | |
3504 | (prog->sec_idx == sec_idx && prog->sec_insn_off <= insn_idx)) | |
3505 | l = m; | |
3506 | else | |
3507 | r = m - 1; | |
3508 | } | |
3509 | /* matching program could be at index l, but it still might be the | |
3510 | * wrong one, so we need to double check conditions for the last time | |
3511 | */ | |
3512 | prog = &obj->programs[l]; | |
3513 | if (prog->sec_idx == sec_idx && prog_contains_insn(prog, insn_idx)) | |
3514 | return prog; | |
3515 | return NULL; | |
3516 | } | |
3517 | ||
34090915 | 3518 | static int |
c3c55696 | 3519 | bpf_object__collect_prog_relos(struct bpf_object *obj, GElf_Shdr *shdr, Elf_Data *data) |
34090915 | 3520 | { |
48cca7e4 | 3521 | Elf_Data *symbols = obj->efile.symbols; |
9c0f8cbd AN |
3522 | const char *relo_sec_name, *sec_name; |
3523 | size_t sec_idx = shdr->sh_info; | |
c3c55696 AN |
3524 | struct bpf_program *prog; |
3525 | struct reloc_desc *relos; | |
1f8e2bcb | 3526 | int err, i, nrels; |
c3c55696 AN |
3527 | const char *sym_name; |
3528 | __u32 insn_idx; | |
3529 | GElf_Sym sym; | |
3530 | GElf_Rel rel; | |
34090915 | 3531 | |
9c0f8cbd AN |
3532 | relo_sec_name = elf_sec_str(obj, shdr->sh_name); |
3533 | sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, sec_idx)); | |
3534 | if (!relo_sec_name || !sec_name) | |
3535 | return -EINVAL; | |
3536 | ||
3537 | pr_debug("sec '%s': collecting relocation for section(%zu) '%s'\n", | |
3538 | relo_sec_name, sec_idx, sec_name); | |
34090915 WN |
3539 | nrels = shdr->sh_size / shdr->sh_entsize; |
3540 | ||
34090915 | 3541 | for (i = 0; i < nrels; i++) { |
34090915 | 3542 | if (!gelf_getrel(data, i, &rel)) { |
9c0f8cbd | 3543 | pr_warn("sec '%s': failed to get relo #%d\n", relo_sec_name, i); |
6371ca3b | 3544 | return -LIBBPF_ERRNO__FORMAT; |
34090915 | 3545 | } |
399dc65e | 3546 | if (!gelf_getsym(symbols, GELF_R_SYM(rel.r_info), &sym)) { |
9c0f8cbd AN |
3547 | pr_warn("sec '%s': symbol 0x%zx not found for relo #%d\n", |
3548 | relo_sec_name, (size_t)GELF_R_SYM(rel.r_info), i); | |
6371ca3b | 3549 | return -LIBBPF_ERRNO__FORMAT; |
34090915 | 3550 | } |
9c0f8cbd AN |
3551 | if (rel.r_offset % BPF_INSN_SZ) { |
3552 | pr_warn("sec '%s': invalid offset 0x%zx for relo #%d\n", | |
3553 | relo_sec_name, (size_t)GELF_R_SYM(rel.r_info), i); | |
1f8e2bcb | 3554 | return -LIBBPF_ERRNO__FORMAT; |
9c0f8cbd | 3555 | } |
d859900c | 3556 | |
9c0f8cbd | 3557 | insn_idx = rel.r_offset / BPF_INSN_SZ; |
c3c55696 AN |
3558 | /* relocations against static functions are recorded as |
3559 | * relocations against the section that contains a function; | |
3560 | * in such case, symbol will be STT_SECTION and sym.st_name | |
3561 | * will point to empty string (0), so fetch section name | |
3562 | * instead | |
3563 | */ | |
3564 | if (GELF_ST_TYPE(sym.st_info) == STT_SECTION && sym.st_name == 0) | |
3565 | sym_name = elf_sec_name(obj, elf_sec_by_idx(obj, sym.st_shndx)); | |
3566 | else | |
3567 | sym_name = elf_sym_str(obj, sym.st_name); | |
3568 | sym_name = sym_name ?: "<?"; | |
d859900c | 3569 | |
9c0f8cbd AN |
3570 | pr_debug("sec '%s': relo #%d: insn #%u against '%s'\n", |
3571 | relo_sec_name, i, insn_idx, sym_name); | |
666810e8 | 3572 | |
c3c55696 AN |
3573 | prog = find_prog_by_sec_insn(obj, sec_idx, insn_idx); |
3574 | if (!prog) { | |
3575 | pr_warn("sec '%s': relo #%d: program not found in section '%s' for insn #%u\n", | |
3576 | relo_sec_name, i, sec_name, insn_idx); | |
3577 | return -LIBBPF_ERRNO__RELOC; | |
3578 | } | |
3579 | ||
3580 | relos = libbpf_reallocarray(prog->reloc_desc, | |
3581 | prog->nr_reloc + 1, sizeof(*relos)); | |
3582 | if (!relos) | |
3583 | return -ENOMEM; | |
3584 | prog->reloc_desc = relos; | |
3585 | ||
3586 | /* adjust insn_idx to local BPF program frame of reference */ | |
3587 | insn_idx -= prog->sec_insn_off; | |
3588 | err = bpf_program__record_reloc(prog, &relos[prog->nr_reloc], | |
9c0f8cbd | 3589 | insn_idx, sym_name, &sym, &rel); |
1f8e2bcb AN |
3590 | if (err) |
3591 | return err; | |
c3c55696 AN |
3592 | |
3593 | prog->nr_reloc++; | |
34090915 WN |
3594 | } |
3595 | return 0; | |
3596 | } | |
3597 | ||
abd29c93 | 3598 | static int bpf_map_find_btf_info(struct bpf_object *obj, struct bpf_map *map) |
8a138aed MKL |
3599 | { |
3600 | struct bpf_map_def *def = &map->def; | |
d859900c | 3601 | __u32 key_type_id = 0, value_type_id = 0; |
96408c43 | 3602 | int ret; |
8a138aed | 3603 | |
590a0088 MKL |
3604 | /* if it's BTF-defined map, we don't need to search for type IDs. |
3605 | * For struct_ops map, it does not need btf_key_type_id and | |
3606 | * btf_value_type_id. | |
3607 | */ | |
3608 | if (map->sec_idx == obj->efile.btf_maps_shndx || | |
3609 | bpf_map__is_struct_ops(map)) | |
abd29c93 AN |
3610 | return 0; |
3611 | ||
d859900c | 3612 | if (!bpf_map__is_internal(map)) { |
abd29c93 | 3613 | ret = btf__get_map_kv_tids(obj->btf, map->name, def->key_size, |
d859900c DB |
3614 | def->value_size, &key_type_id, |
3615 | &value_type_id); | |
3616 | } else { | |
3617 | /* | |
3618 | * LLVM annotates global data differently in BTF, that is, | |
3619 | * only as '.data', '.bss' or '.rodata'. | |
3620 | */ | |
abd29c93 | 3621 | ret = btf__find_by_name(obj->btf, |
d859900c DB |
3622 | libbpf_type_to_btf_name[map->libbpf_type]); |
3623 | } | |
3624 | if (ret < 0) | |
96408c43 | 3625 | return ret; |
8a138aed | 3626 | |
96408c43 | 3627 | map->btf_key_type_id = key_type_id; |
d859900c DB |
3628 | map->btf_value_type_id = bpf_map__is_internal(map) ? |
3629 | ret : value_type_id; | |
8a138aed MKL |
3630 | return 0; |
3631 | } | |
3632 | ||
26736eb9 JK |
3633 | int bpf_map__reuse_fd(struct bpf_map *map, int fd) |
3634 | { | |
3635 | struct bpf_map_info info = {}; | |
3636 | __u32 len = sizeof(info); | |
3637 | int new_fd, err; | |
3638 | char *new_name; | |
3639 | ||
3640 | err = bpf_obj_get_info_by_fd(fd, &info, &len); | |
3641 | if (err) | |
3642 | return err; | |
3643 | ||
3644 | new_name = strdup(info.name); | |
3645 | if (!new_name) | |
3646 | return -errno; | |
3647 | ||
3648 | new_fd = open("/", O_RDONLY | O_CLOEXEC); | |
d1b4574a THJ |
3649 | if (new_fd < 0) { |
3650 | err = -errno; | |
26736eb9 | 3651 | goto err_free_new_name; |
d1b4574a | 3652 | } |
26736eb9 JK |
3653 | |
3654 | new_fd = dup3(fd, new_fd, O_CLOEXEC); | |
d1b4574a THJ |
3655 | if (new_fd < 0) { |
3656 | err = -errno; | |
26736eb9 | 3657 | goto err_close_new_fd; |
d1b4574a | 3658 | } |
26736eb9 JK |
3659 | |
3660 | err = zclose(map->fd); | |
d1b4574a THJ |
3661 | if (err) { |
3662 | err = -errno; | |
26736eb9 | 3663 | goto err_close_new_fd; |
d1b4574a | 3664 | } |
26736eb9 JK |
3665 | free(map->name); |
3666 | ||
3667 | map->fd = new_fd; | |
3668 | map->name = new_name; | |
3669 | map->def.type = info.type; | |
3670 | map->def.key_size = info.key_size; | |
3671 | map->def.value_size = info.value_size; | |
3672 | map->def.max_entries = info.max_entries; | |
3673 | map->def.map_flags = info.map_flags; | |
3674 | map->btf_key_type_id = info.btf_key_type_id; | |
3675 | map->btf_value_type_id = info.btf_value_type_id; | |
ec6d5f47 | 3676 | map->reused = true; |
26736eb9 JK |
3677 | |
3678 | return 0; | |
3679 | ||
3680 | err_close_new_fd: | |
3681 | close(new_fd); | |
3682 | err_free_new_name: | |
3683 | free(new_name); | |
d1b4574a | 3684 | return err; |
26736eb9 JK |
3685 | } |
3686 | ||
1bdb6c9a | 3687 | __u32 bpf_map__max_entries(const struct bpf_map *map) |
1a11a4c7 | 3688 | { |
1bdb6c9a AN |
3689 | return map->def.max_entries; |
3690 | } | |
1a11a4c7 | 3691 | |
1bdb6c9a AN |
3692 | int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries) |
3693 | { | |
1a11a4c7 AI |
3694 | if (map->fd >= 0) |
3695 | return -EBUSY; | |
1a11a4c7 | 3696 | map->def.max_entries = max_entries; |
1a11a4c7 AI |
3697 | return 0; |
3698 | } | |
3699 | ||
1bdb6c9a AN |
3700 | int bpf_map__resize(struct bpf_map *map, __u32 max_entries) |
3701 | { | |
3702 | if (!map || !max_entries) | |
3703 | return -EINVAL; | |
3704 | ||
3705 | return bpf_map__set_max_entries(map, max_entries); | |
3706 | } | |
3707 | ||
47eff617 | 3708 | static int |
fd9eef1a | 3709 | bpf_object__probe_loading(struct bpf_object *obj) |
47eff617 SF |
3710 | { |
3711 | struct bpf_load_program_attr attr; | |
3712 | char *cp, errmsg[STRERR_BUFSIZE]; | |
3713 | struct bpf_insn insns[] = { | |
3714 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
3715 | BPF_EXIT_INSN(), | |
3716 | }; | |
3717 | int ret; | |
3718 | ||
3719 | /* make sure basic loading works */ | |
3720 | ||
3721 | memset(&attr, 0, sizeof(attr)); | |
3722 | attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; | |
3723 | attr.insns = insns; | |
3724 | attr.insns_cnt = ARRAY_SIZE(insns); | |
3725 | attr.license = "GPL"; | |
3726 | ||
3727 | ret = bpf_load_program_xattr(&attr, NULL, 0); | |
3728 | if (ret < 0) { | |
fd9eef1a EC |
3729 | ret = errno; |
3730 | cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); | |
3731 | pr_warn("Error in %s():%s(%d). Couldn't load trivial BPF " | |
3732 | "program. Make sure your kernel supports BPF " | |
3733 | "(CONFIG_BPF_SYSCALL=y) and/or that RLIMIT_MEMLOCK is " | |
3734 | "set to big enough value.\n", __func__, cp, ret); | |
3735 | return -ret; | |
47eff617 SF |
3736 | } |
3737 | close(ret); | |
3738 | ||
fd9eef1a EC |
3739 | return 0; |
3740 | } | |
3741 | ||
bb180fb2 AN |
3742 | static int probe_fd(int fd) |
3743 | { | |
3744 | if (fd >= 0) | |
3745 | close(fd); | |
3746 | return fd >= 0; | |
3747 | } | |
3748 | ||
47b6cb4d | 3749 | static int probe_kern_prog_name(void) |
fd9eef1a EC |
3750 | { |
3751 | struct bpf_load_program_attr attr; | |
3752 | struct bpf_insn insns[] = { | |
3753 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
3754 | BPF_EXIT_INSN(), | |
3755 | }; | |
3756 | int ret; | |
3757 | ||
3758 | /* make sure loading with name works */ | |
47eff617 | 3759 | |
fd9eef1a EC |
3760 | memset(&attr, 0, sizeof(attr)); |
3761 | attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; | |
3762 | attr.insns = insns; | |
3763 | attr.insns_cnt = ARRAY_SIZE(insns); | |
3764 | attr.license = "GPL"; | |
47eff617 SF |
3765 | attr.name = "test"; |
3766 | ret = bpf_load_program_xattr(&attr, NULL, 0); | |
bb180fb2 | 3767 | return probe_fd(ret); |
47eff617 SF |
3768 | } |
3769 | ||
47b6cb4d | 3770 | static int probe_kern_global_data(void) |
8837fe5d DB |
3771 | { |
3772 | struct bpf_load_program_attr prg_attr; | |
3773 | struct bpf_create_map_attr map_attr; | |
3774 | char *cp, errmsg[STRERR_BUFSIZE]; | |
3775 | struct bpf_insn insns[] = { | |
3776 | BPF_LD_MAP_VALUE(BPF_REG_1, 0, 16), | |
3777 | BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 42), | |
3778 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
3779 | BPF_EXIT_INSN(), | |
3780 | }; | |
3781 | int ret, map; | |
3782 | ||
3783 | memset(&map_attr, 0, sizeof(map_attr)); | |
3784 | map_attr.map_type = BPF_MAP_TYPE_ARRAY; | |
3785 | map_attr.key_size = sizeof(int); | |
3786 | map_attr.value_size = 32; | |
3787 | map_attr.max_entries = 1; | |
3788 | ||
3789 | map = bpf_create_map_xattr(&map_attr); | |
3790 | if (map < 0) { | |
23ab656b THJ |
3791 | ret = -errno; |
3792 | cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); | |
be18010e | 3793 | pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n", |
23ab656b THJ |
3794 | __func__, cp, -ret); |
3795 | return ret; | |
8837fe5d DB |
3796 | } |
3797 | ||
3798 | insns[0].imm = map; | |
3799 | ||
3800 | memset(&prg_attr, 0, sizeof(prg_attr)); | |
3801 | prg_attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; | |
3802 | prg_attr.insns = insns; | |
3803 | prg_attr.insns_cnt = ARRAY_SIZE(insns); | |
3804 | prg_attr.license = "GPL"; | |
3805 | ||
3806 | ret = bpf_load_program_xattr(&prg_attr, NULL, 0); | |
47b6cb4d | 3807 | close(map); |
bb180fb2 | 3808 | return probe_fd(ret); |
8837fe5d DB |
3809 | } |
3810 | ||
68b08647 AN |
3811 | static int probe_kern_btf(void) |
3812 | { | |
3813 | static const char strs[] = "\0int"; | |
3814 | __u32 types[] = { | |
3815 | /* int */ | |
3816 | BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), | |
3817 | }; | |
3818 | ||
3819 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), | |
3820 | strs, sizeof(strs))); | |
3821 | } | |
3822 | ||
47b6cb4d | 3823 | static int probe_kern_btf_func(void) |
d7c4b398 | 3824 | { |
8983b731 | 3825 | static const char strs[] = "\0int\0x\0a"; |
d7c4b398 AN |
3826 | /* void x(int a) {} */ |
3827 | __u32 types[] = { | |
3828 | /* int */ | |
3829 | BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ | |
3830 | /* FUNC_PROTO */ /* [2] */ | |
3831 | BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), | |
3832 | BTF_PARAM_ENC(7, 1), | |
3833 | /* FUNC x */ /* [3] */ | |
3834 | BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2), | |
3835 | }; | |
d7c4b398 | 3836 | |
bb180fb2 AN |
3837 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), |
3838 | strs, sizeof(strs))); | |
d7c4b398 AN |
3839 | } |
3840 | ||
47b6cb4d | 3841 | static int probe_kern_btf_func_global(void) |
2d3eb67f AS |
3842 | { |
3843 | static const char strs[] = "\0int\0x\0a"; | |
3844 | /* static void x(int a) {} */ | |
3845 | __u32 types[] = { | |
3846 | /* int */ | |
3847 | BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ | |
3848 | /* FUNC_PROTO */ /* [2] */ | |
3849 | BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), | |
3850 | BTF_PARAM_ENC(7, 1), | |
3851 | /* FUNC x BTF_FUNC_GLOBAL */ /* [3] */ | |
3852 | BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, BTF_FUNC_GLOBAL), 2), | |
3853 | }; | |
2d3eb67f | 3854 | |
bb180fb2 AN |
3855 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), |
3856 | strs, sizeof(strs))); | |
2d3eb67f AS |
3857 | } |
3858 | ||
47b6cb4d | 3859 | static int probe_kern_btf_datasec(void) |
d7c4b398 | 3860 | { |
8983b731 | 3861 | static const char strs[] = "\0x\0.data"; |
d7c4b398 AN |
3862 | /* static int a; */ |
3863 | __u32 types[] = { | |
3864 | /* int */ | |
3865 | BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ | |
3866 | /* VAR x */ /* [2] */ | |
3867 | BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), | |
3868 | BTF_VAR_STATIC, | |
3869 | /* DATASEC val */ /* [3] */ | |
3870 | BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4), | |
3871 | BTF_VAR_SECINFO_ENC(2, 0, 4), | |
3872 | }; | |
cfd49210 | 3873 | |
bb180fb2 AN |
3874 | return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), |
3875 | strs, sizeof(strs))); | |
d7c4b398 AN |
3876 | } |
3877 | ||
47b6cb4d | 3878 | static int probe_kern_array_mmap(void) |
7fe74b43 AN |
3879 | { |
3880 | struct bpf_create_map_attr attr = { | |
3881 | .map_type = BPF_MAP_TYPE_ARRAY, | |
3882 | .map_flags = BPF_F_MMAPABLE, | |
3883 | .key_size = sizeof(int), | |
3884 | .value_size = sizeof(int), | |
3885 | .max_entries = 1, | |
3886 | }; | |
7fe74b43 | 3887 | |
bb180fb2 | 3888 | return probe_fd(bpf_create_map_xattr(&attr)); |
7fe74b43 AN |
3889 | } |
3890 | ||
47b6cb4d | 3891 | static int probe_kern_exp_attach_type(void) |
25498a19 AN |
3892 | { |
3893 | struct bpf_load_program_attr attr; | |
3894 | struct bpf_insn insns[] = { | |
3895 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
3896 | BPF_EXIT_INSN(), | |
3897 | }; | |
25498a19 AN |
3898 | |
3899 | memset(&attr, 0, sizeof(attr)); | |
3900 | /* use any valid combination of program type and (optional) | |
3901 | * non-zero expected attach type (i.e., not a BPF_CGROUP_INET_INGRESS) | |
3902 | * to see if kernel supports expected_attach_type field for | |
3903 | * BPF_PROG_LOAD command | |
3904 | */ | |
3905 | attr.prog_type = BPF_PROG_TYPE_CGROUP_SOCK; | |
3906 | attr.expected_attach_type = BPF_CGROUP_INET_SOCK_CREATE; | |
3907 | attr.insns = insns; | |
3908 | attr.insns_cnt = ARRAY_SIZE(insns); | |
3909 | attr.license = "GPL"; | |
3910 | ||
bb180fb2 | 3911 | return probe_fd(bpf_load_program_xattr(&attr, NULL, 0)); |
25498a19 AN |
3912 | } |
3913 | ||
109cea5a AN |
3914 | static int probe_kern_probe_read_kernel(void) |
3915 | { | |
3916 | struct bpf_load_program_attr attr; | |
3917 | struct bpf_insn insns[] = { | |
3918 | BPF_MOV64_REG(BPF_REG_1, BPF_REG_10), /* r1 = r10 (fp) */ | |
3919 | BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8), /* r1 += -8 */ | |
3920 | BPF_MOV64_IMM(BPF_REG_2, 8), /* r2 = 8 */ | |
3921 | BPF_MOV64_IMM(BPF_REG_3, 0), /* r3 = 0 */ | |
3922 | BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_probe_read_kernel), | |
3923 | BPF_EXIT_INSN(), | |
3924 | }; | |
3925 | ||
3926 | memset(&attr, 0, sizeof(attr)); | |
3927 | attr.prog_type = BPF_PROG_TYPE_KPROBE; | |
3928 | attr.insns = insns; | |
3929 | attr.insns_cnt = ARRAY_SIZE(insns); | |
3930 | attr.license = "GPL"; | |
3931 | ||
3932 | return probe_fd(bpf_load_program_xattr(&attr, NULL, 0)); | |
3933 | } | |
3934 | ||
5d23328d YZ |
3935 | static int probe_prog_bind_map(void) |
3936 | { | |
3937 | struct bpf_load_program_attr prg_attr; | |
3938 | struct bpf_create_map_attr map_attr; | |
3939 | char *cp, errmsg[STRERR_BUFSIZE]; | |
3940 | struct bpf_insn insns[] = { | |
3941 | BPF_MOV64_IMM(BPF_REG_0, 0), | |
3942 | BPF_EXIT_INSN(), | |
3943 | }; | |
3944 | int ret, map, prog; | |
3945 | ||
3946 | memset(&map_attr, 0, sizeof(map_attr)); | |
3947 | map_attr.map_type = BPF_MAP_TYPE_ARRAY; | |
3948 | map_attr.key_size = sizeof(int); | |
3949 | map_attr.value_size = 32; | |
3950 | map_attr.max_entries = 1; | |
3951 | ||
3952 | map = bpf_create_map_xattr(&map_attr); | |
3953 | if (map < 0) { | |
3954 | ret = -errno; | |
3955 | cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); | |
3956 | pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n", | |
3957 | __func__, cp, -ret); | |
3958 | return ret; | |
3959 | } | |
3960 | ||
3961 | memset(&prg_attr, 0, sizeof(prg_attr)); | |
3962 | prg_attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; | |
3963 | prg_attr.insns = insns; | |
3964 | prg_attr.insns_cnt = ARRAY_SIZE(insns); | |
3965 | prg_attr.license = "GPL"; | |
3966 | ||
3967 | prog = bpf_load_program_xattr(&prg_attr, NULL, 0); | |
3968 | if (prog < 0) { | |
3969 | close(map); | |
3970 | return 0; | |
3971 | } | |
3972 | ||
3973 | ret = bpf_prog_bind_map(prog, map, NULL); | |
3974 | ||
3975 | close(map); | |
3976 | close(prog); | |
3977 | ||
3978 | return ret >= 0; | |
3979 | } | |
3980 | ||
4f33a53d AN |
3981 | static int probe_module_btf(void) |
3982 | { | |
3983 | static const char strs[] = "\0int"; | |
3984 | __u32 types[] = { | |
3985 | /* int */ | |
3986 | BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), | |
3987 | }; | |
3988 | struct bpf_btf_info info; | |
3989 | __u32 len = sizeof(info); | |
3990 | char name[16]; | |
3991 | int fd, err; | |
3992 | ||
3993 | fd = libbpf__load_raw_btf((char *)types, sizeof(types), strs, sizeof(strs)); | |
3994 | if (fd < 0) | |
3995 | return 0; /* BTF not supported at all */ | |
3996 | ||
3997 | memset(&info, 0, sizeof(info)); | |
3998 | info.name = ptr_to_u64(name); | |
3999 | info.name_len = sizeof(name); | |
4000 | ||
4001 | /* check that BPF_OBJ_GET_INFO_BY_FD supports specifying name pointer; | |
4002 | * kernel's module BTF support coincides with support for | |
4003 | * name/name_len fields in struct bpf_btf_info. | |
4004 | */ | |
4005 | err = bpf_obj_get_info_by_fd(fd, &info, &len); | |
4006 | close(fd); | |
4007 | return !err; | |
4008 | } | |
4009 | ||
47b6cb4d AN |
4010 | enum kern_feature_result { |
4011 | FEAT_UNKNOWN = 0, | |
4012 | FEAT_SUPPORTED = 1, | |
4013 | FEAT_MISSING = 2, | |
4014 | }; | |
4015 | ||
4016 | typedef int (*feature_probe_fn)(void); | |
4017 | ||
4018 | static struct kern_feature_desc { | |
4019 | const char *desc; | |
4020 | feature_probe_fn probe; | |
4021 | enum kern_feature_result res; | |
4022 | } feature_probes[__FEAT_CNT] = { | |
4023 | [FEAT_PROG_NAME] = { | |
4024 | "BPF program name", probe_kern_prog_name, | |
4025 | }, | |
4026 | [FEAT_GLOBAL_DATA] = { | |
4027 | "global variables", probe_kern_global_data, | |
4028 | }, | |
68b08647 AN |
4029 | [FEAT_BTF] = { |
4030 | "minimal BTF", probe_kern_btf, | |
4031 | }, | |
47b6cb4d AN |
4032 | [FEAT_BTF_FUNC] = { |
4033 | "BTF functions", probe_kern_btf_func, | |
4034 | }, | |
4035 | [FEAT_BTF_GLOBAL_FUNC] = { | |
4036 | "BTF global function", probe_kern_btf_func_global, | |
4037 | }, | |
4038 | [FEAT_BTF_DATASEC] = { | |
4039 | "BTF data section and variable", probe_kern_btf_datasec, | |
4040 | }, | |
4041 | [FEAT_ARRAY_MMAP] = { | |
4042 | "ARRAY map mmap()", probe_kern_array_mmap, | |
4043 | }, | |
4044 | [FEAT_EXP_ATTACH_TYPE] = { | |
4045 | "BPF_PROG_LOAD expected_attach_type attribute", | |
4046 | probe_kern_exp_attach_type, | |
4047 | }, | |
109cea5a AN |
4048 | [FEAT_PROBE_READ_KERN] = { |
4049 | "bpf_probe_read_kernel() helper", probe_kern_probe_read_kernel, | |
5d23328d YZ |
4050 | }, |
4051 | [FEAT_PROG_BIND_MAP] = { | |
4052 | "BPF_PROG_BIND_MAP support", probe_prog_bind_map, | |
4f33a53d AN |
4053 | }, |
4054 | [FEAT_MODULE_BTF] = { | |
4055 | "module BTF support", probe_module_btf, | |
4056 | }, | |
47b6cb4d | 4057 | }; |
8837fe5d | 4058 | |
47b6cb4d AN |
4059 | static bool kernel_supports(enum kern_feature_id feat_id) |
4060 | { | |
4061 | struct kern_feature_desc *feat = &feature_probes[feat_id]; | |
4062 | int ret; | |
4063 | ||
4064 | if (READ_ONCE(feat->res) == FEAT_UNKNOWN) { | |
4065 | ret = feat->probe(); | |
4066 | if (ret > 0) { | |
4067 | WRITE_ONCE(feat->res, FEAT_SUPPORTED); | |
4068 | } else if (ret == 0) { | |
4069 | WRITE_ONCE(feat->res, FEAT_MISSING); | |
4070 | } else { | |
4071 | pr_warn("Detection of kernel %s support failed: %d\n", feat->desc, ret); | |
4072 | WRITE_ONCE(feat->res, FEAT_MISSING); | |
4073 | } | |
8837fe5d DB |
4074 | } |
4075 | ||
47b6cb4d | 4076 | return READ_ONCE(feat->res) == FEAT_SUPPORTED; |
47eff617 SF |
4077 | } |
4078 | ||
57a00f41 THJ |
4079 | static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd) |
4080 | { | |
4081 | struct bpf_map_info map_info = {}; | |
4082 | char msg[STRERR_BUFSIZE]; | |
4083 | __u32 map_info_len; | |
4084 | ||
4085 | map_info_len = sizeof(map_info); | |
4086 | ||
4087 | if (bpf_obj_get_info_by_fd(map_fd, &map_info, &map_info_len)) { | |
4088 | pr_warn("failed to get map info for map FD %d: %s\n", | |
4089 | map_fd, libbpf_strerror_r(errno, msg, sizeof(msg))); | |
4090 | return false; | |
4091 | } | |
4092 | ||
4093 | return (map_info.type == map->def.type && | |
4094 | map_info.key_size == map->def.key_size && | |
4095 | map_info.value_size == map->def.value_size && | |
4096 | map_info.max_entries == map->def.max_entries && | |
4097 | map_info.map_flags == map->def.map_flags); | |
4098 | } | |
4099 | ||
4100 | static int | |
4101 | bpf_object__reuse_map(struct bpf_map *map) | |
4102 | { | |
4103 | char *cp, errmsg[STRERR_BUFSIZE]; | |
4104 | int err, pin_fd; | |
4105 | ||
4106 | pin_fd = bpf_obj_get(map->pin_path); | |
4107 | if (pin_fd < 0) { | |
4108 | err = -errno; | |
4109 | if (err == -ENOENT) { | |
4110 | pr_debug("found no pinned map to reuse at '%s'\n", | |
4111 | map->pin_path); | |
4112 | return 0; | |
4113 | } | |
4114 | ||
4115 | cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); | |
4116 | pr_warn("couldn't retrieve pinned map '%s': %s\n", | |
4117 | map->pin_path, cp); | |
4118 | return err; | |
4119 | } | |
4120 | ||
4121 | if (!map_is_reuse_compat(map, pin_fd)) { | |
4122 | pr_warn("couldn't reuse pinned map at '%s': parameter mismatch\n", | |
4123 | map->pin_path); | |
4124 | close(pin_fd); | |
4125 | return -EINVAL; | |
4126 | } | |
4127 | ||
4128 | err = bpf_map__reuse_fd(map, pin_fd); | |
4129 | if (err) { | |
4130 | close(pin_fd); | |
4131 | return err; | |
4132 | } | |
4133 | map->pinned = true; | |
4134 | pr_debug("reused pinned map at '%s'\n", map->pin_path); | |
4135 | ||
4136 | return 0; | |
4137 | } | |
4138 | ||
d859900c DB |
4139 | static int |
4140 | bpf_object__populate_internal_map(struct bpf_object *obj, struct bpf_map *map) | |
4141 | { | |
166750bc | 4142 | enum libbpf_map_type map_type = map->libbpf_type; |
d859900c DB |
4143 | char *cp, errmsg[STRERR_BUFSIZE]; |
4144 | int err, zero = 0; | |
d859900c | 4145 | |
eba9c5f4 AN |
4146 | err = bpf_map_update_elem(map->fd, &zero, map->mmaped, 0); |
4147 | if (err) { | |
4148 | err = -errno; | |
4149 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
4150 | pr_warn("Error setting initial map(%s) contents: %s\n", | |
4151 | map->name, cp); | |
4152 | return err; | |
4153 | } | |
d859900c | 4154 | |
81bfdd08 AN |
4155 | /* Freeze .rodata and .kconfig map as read-only from syscall side. */ |
4156 | if (map_type == LIBBPF_MAP_RODATA || map_type == LIBBPF_MAP_KCONFIG) { | |
d859900c DB |
4157 | err = bpf_map_freeze(map->fd); |
4158 | if (err) { | |
eba9c5f4 AN |
4159 | err = -errno; |
4160 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
be18010e KW |
4161 | pr_warn("Error freezing map(%s) as read-only: %s\n", |
4162 | map->name, cp); | |
eba9c5f4 | 4163 | return err; |
d859900c DB |
4164 | } |
4165 | } | |
eba9c5f4 | 4166 | return 0; |
d859900c DB |
4167 | } |
4168 | ||
2d39d7c5 AN |
4169 | static void bpf_map__destroy(struct bpf_map *map); |
4170 | ||
4171 | static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map) | |
4172 | { | |
4173 | struct bpf_create_map_attr create_attr; | |
4174 | struct bpf_map_def *def = &map->def; | |
4175 | ||
4176 | memset(&create_attr, 0, sizeof(create_attr)); | |
4177 | ||
47b6cb4d | 4178 | if (kernel_supports(FEAT_PROG_NAME)) |
2d39d7c5 AN |
4179 | create_attr.name = map->name; |
4180 | create_attr.map_ifindex = map->map_ifindex; | |
4181 | create_attr.map_type = def->type; | |
4182 | create_attr.map_flags = def->map_flags; | |
4183 | create_attr.key_size = def->key_size; | |
4184 | create_attr.value_size = def->value_size; | |
1bdb6c9a | 4185 | create_attr.numa_node = map->numa_node; |
2d39d7c5 AN |
4186 | |
4187 | if (def->type == BPF_MAP_TYPE_PERF_EVENT_ARRAY && !def->max_entries) { | |
4188 | int nr_cpus; | |
4189 | ||
4190 | nr_cpus = libbpf_num_possible_cpus(); | |
4191 | if (nr_cpus < 0) { | |
4192 | pr_warn("map '%s': failed to determine number of system CPUs: %d\n", | |
4193 | map->name, nr_cpus); | |
4194 | return nr_cpus; | |
4195 | } | |
4196 | pr_debug("map '%s': setting size to %d\n", map->name, nr_cpus); | |
4197 | create_attr.max_entries = nr_cpus; | |
4198 | } else { | |
4199 | create_attr.max_entries = def->max_entries; | |
4200 | } | |
4201 | ||
4202 | if (bpf_map__is_struct_ops(map)) | |
4203 | create_attr.btf_vmlinux_value_type_id = | |
4204 | map->btf_vmlinux_value_type_id; | |
4205 | ||
4206 | create_attr.btf_fd = 0; | |
4207 | create_attr.btf_key_type_id = 0; | |
4208 | create_attr.btf_value_type_id = 0; | |
0f0e55d8 | 4209 | if (obj->btf && btf__fd(obj->btf) >= 0 && !bpf_map_find_btf_info(obj, map)) { |
2d39d7c5 AN |
4210 | create_attr.btf_fd = btf__fd(obj->btf); |
4211 | create_attr.btf_key_type_id = map->btf_key_type_id; | |
4212 | create_attr.btf_value_type_id = map->btf_value_type_id; | |
4213 | } | |
4214 | ||
646f02ff AN |
4215 | if (bpf_map_type__is_map_in_map(def->type)) { |
4216 | if (map->inner_map) { | |
4217 | int err; | |
4218 | ||
4219 | err = bpf_object__create_map(obj, map->inner_map); | |
4220 | if (err) { | |
4221 | pr_warn("map '%s': failed to create inner map: %d\n", | |
4222 | map->name, err); | |
4223 | return err; | |
4224 | } | |
4225 | map->inner_map_fd = bpf_map__fd(map->inner_map); | |
4226 | } | |
4227 | if (map->inner_map_fd >= 0) | |
4228 | create_attr.inner_map_fd = map->inner_map_fd; | |
4229 | } | |
4230 | ||
2d39d7c5 AN |
4231 | map->fd = bpf_create_map_xattr(&create_attr); |
4232 | if (map->fd < 0 && (create_attr.btf_key_type_id || | |
4233 | create_attr.btf_value_type_id)) { | |
4234 | char *cp, errmsg[STRERR_BUFSIZE]; | |
4235 | int err = -errno; | |
4236 | ||
4237 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
4238 | pr_warn("Error in bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n", | |
4239 | map->name, cp, err); | |
4240 | create_attr.btf_fd = 0; | |
4241 | create_attr.btf_key_type_id = 0; | |
4242 | create_attr.btf_value_type_id = 0; | |
4243 | map->btf_key_type_id = 0; | |
4244 | map->btf_value_type_id = 0; | |
4245 | map->fd = bpf_create_map_xattr(&create_attr); | |
4246 | } | |
4247 | ||
4248 | if (map->fd < 0) | |
4249 | return -errno; | |
4250 | ||
646f02ff AN |
4251 | if (bpf_map_type__is_map_in_map(def->type) && map->inner_map) { |
4252 | bpf_map__destroy(map->inner_map); | |
4253 | zfree(&map->inner_map); | |
4254 | } | |
4255 | ||
2d39d7c5 AN |
4256 | return 0; |
4257 | } | |
4258 | ||
a0f2b7ac HL |
4259 | static int init_map_slots(struct bpf_map *map) |
4260 | { | |
4261 | const struct bpf_map *targ_map; | |
4262 | unsigned int i; | |
4263 | int fd, err; | |
4264 | ||
4265 | for (i = 0; i < map->init_slots_sz; i++) { | |
4266 | if (!map->init_slots[i]) | |
4267 | continue; | |
4268 | ||
4269 | targ_map = map->init_slots[i]; | |
4270 | fd = bpf_map__fd(targ_map); | |
4271 | err = bpf_map_update_elem(map->fd, &i, &fd, 0); | |
4272 | if (err) { | |
4273 | err = -errno; | |
4274 | pr_warn("map '%s': failed to initialize slot [%d] to map '%s' fd=%d: %d\n", | |
4275 | map->name, i, targ_map->name, | |
4276 | fd, err); | |
4277 | return err; | |
4278 | } | |
4279 | pr_debug("map '%s': slot [%d] set to map '%s' fd=%d\n", | |
4280 | map->name, i, targ_map->name, fd); | |
4281 | } | |
4282 | ||
4283 | zfree(&map->init_slots); | |
4284 | map->init_slots_sz = 0; | |
4285 | ||
4286 | return 0; | |
4287 | } | |
4288 | ||
52d3352e WN |
4289 | static int |
4290 | bpf_object__create_maps(struct bpf_object *obj) | |
4291 | { | |
2d39d7c5 AN |
4292 | struct bpf_map *map; |
4293 | char *cp, errmsg[STRERR_BUFSIZE]; | |
4294 | unsigned int i, j; | |
8a138aed | 4295 | int err; |
52d3352e | 4296 | |
9d759a9b | 4297 | for (i = 0; i < obj->nr_maps; i++) { |
2d39d7c5 | 4298 | map = &obj->maps[i]; |
8a138aed | 4299 | |
57a00f41 THJ |
4300 | if (map->pin_path) { |
4301 | err = bpf_object__reuse_map(map); | |
4302 | if (err) { | |
2d39d7c5 | 4303 | pr_warn("map '%s': error reusing pinned map\n", |
57a00f41 | 4304 | map->name); |
2d39d7c5 | 4305 | goto err_out; |
57a00f41 THJ |
4306 | } |
4307 | } | |
4308 | ||
26736eb9 | 4309 | if (map->fd >= 0) { |
2d39d7c5 | 4310 | pr_debug("map '%s': skipping creation (preset fd=%d)\n", |
26736eb9 | 4311 | map->name, map->fd); |
2c193d32 HL |
4312 | } else { |
4313 | err = bpf_object__create_map(obj, map); | |
4314 | if (err) | |
d859900c | 4315 | goto err_out; |
d859900c | 4316 | |
2c193d32 HL |
4317 | pr_debug("map '%s': created successfully, fd=%d\n", |
4318 | map->name, map->fd); | |
646f02ff | 4319 | |
2c193d32 HL |
4320 | if (bpf_map__is_internal(map)) { |
4321 | err = bpf_object__populate_internal_map(obj, map); | |
4322 | if (err < 0) { | |
4323 | zclose(map->fd); | |
4324 | goto err_out; | |
4325 | } | |
d859900c | 4326 | } |
646f02ff | 4327 | |
2c193d32 HL |
4328 | if (map->init_slots_sz) { |
4329 | err = init_map_slots(map); | |
4330 | if (err < 0) { | |
4331 | zclose(map->fd); | |
646f02ff AN |
4332 | goto err_out; |
4333 | } | |
646f02ff | 4334 | } |
646f02ff AN |
4335 | } |
4336 | ||
57a00f41 THJ |
4337 | if (map->pin_path && !map->pinned) { |
4338 | err = bpf_map__pin(map, NULL); | |
4339 | if (err) { | |
2d39d7c5 AN |
4340 | pr_warn("map '%s': failed to auto-pin at '%s': %d\n", |
4341 | map->name, map->pin_path, err); | |
4342 | zclose(map->fd); | |
4343 | goto err_out; | |
57a00f41 THJ |
4344 | } |
4345 | } | |
52d3352e WN |
4346 | } |
4347 | ||
52d3352e | 4348 | return 0; |
2d39d7c5 AN |
4349 | |
4350 | err_out: | |
4351 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
4352 | pr_warn("map '%s': failed to create: %s(%d)\n", map->name, cp, err); | |
4353 | pr_perm_msg(err); | |
4354 | for (j = 0; j < i; j++) | |
4355 | zclose(obj->maps[j].fd); | |
4356 | return err; | |
52d3352e WN |
4357 | } |
4358 | ||
ddc7c304 AN |
4359 | #define BPF_CORE_SPEC_MAX_LEN 64 |
4360 | ||
4361 | /* represents BPF CO-RE field or array element accessor */ | |
4362 | struct bpf_core_accessor { | |
4363 | __u32 type_id; /* struct/union type or array element type */ | |
4364 | __u32 idx; /* field index or array index */ | |
4365 | const char *name; /* field name or NULL for array accessor */ | |
4366 | }; | |
4367 | ||
4368 | struct bpf_core_spec { | |
4369 | const struct btf *btf; | |
4370 | /* high-level spec: named fields and array indices only */ | |
4371 | struct bpf_core_accessor spec[BPF_CORE_SPEC_MAX_LEN]; | |
28b93c64 AN |
4372 | /* original unresolved (no skip_mods_or_typedefs) root type ID */ |
4373 | __u32 root_type_id; | |
4374 | /* CO-RE relocation kind */ | |
4375 | enum bpf_core_relo_kind relo_kind; | |
ddc7c304 AN |
4376 | /* high-level spec length */ |
4377 | int len; | |
4378 | /* raw, low-level spec: 1-to-1 with accessor spec string */ | |
4379 | int raw_spec[BPF_CORE_SPEC_MAX_LEN]; | |
4380 | /* raw spec length */ | |
4381 | int raw_len; | |
ee26dade AN |
4382 | /* field bit offset represented by spec */ |
4383 | __u32 bit_offset; | |
ddc7c304 AN |
4384 | }; |
4385 | ||
4386 | static bool str_is_empty(const char *s) | |
4387 | { | |
4388 | return !s || !s[0]; | |
4389 | } | |
4390 | ||
1b484b30 AN |
4391 | static bool is_flex_arr(const struct btf *btf, |
4392 | const struct bpf_core_accessor *acc, | |
4393 | const struct btf_array *arr) | |
4394 | { | |
4395 | const struct btf_type *t; | |
4396 | ||
4397 | /* not a flexible array, if not inside a struct or has non-zero size */ | |
4398 | if (!acc->name || arr->nelems > 0) | |
4399 | return false; | |
4400 | ||
4401 | /* has to be the last member of enclosing struct */ | |
4402 | t = btf__type_by_id(btf, acc->type_id); | |
4403 | return acc->idx == btf_vlen(t) - 1; | |
4404 | } | |
4405 | ||
28b93c64 AN |
4406 | static const char *core_relo_kind_str(enum bpf_core_relo_kind kind) |
4407 | { | |
4408 | switch (kind) { | |
4409 | case BPF_FIELD_BYTE_OFFSET: return "byte_off"; | |
4410 | case BPF_FIELD_BYTE_SIZE: return "byte_sz"; | |
4411 | case BPF_FIELD_EXISTS: return "field_exists"; | |
4412 | case BPF_FIELD_SIGNED: return "signed"; | |
4413 | case BPF_FIELD_LSHIFT_U64: return "lshift_u64"; | |
4414 | case BPF_FIELD_RSHIFT_U64: return "rshift_u64"; | |
3fc32f40 AN |
4415 | case BPF_TYPE_ID_LOCAL: return "local_type_id"; |
4416 | case BPF_TYPE_ID_TARGET: return "target_type_id"; | |
4417 | case BPF_TYPE_EXISTS: return "type_exists"; | |
4418 | case BPF_TYPE_SIZE: return "type_size"; | |
eacaaed7 AN |
4419 | case BPF_ENUMVAL_EXISTS: return "enumval_exists"; |
4420 | case BPF_ENUMVAL_VALUE: return "enumval_value"; | |
28b93c64 AN |
4421 | default: return "unknown"; |
4422 | } | |
4423 | } | |
4424 | ||
4425 | static bool core_relo_is_field_based(enum bpf_core_relo_kind kind) | |
4426 | { | |
4427 | switch (kind) { | |
4428 | case BPF_FIELD_BYTE_OFFSET: | |
4429 | case BPF_FIELD_BYTE_SIZE: | |
4430 | case BPF_FIELD_EXISTS: | |
4431 | case BPF_FIELD_SIGNED: | |
4432 | case BPF_FIELD_LSHIFT_U64: | |
4433 | case BPF_FIELD_RSHIFT_U64: | |
4434 | return true; | |
4435 | default: | |
4436 | return false; | |
4437 | } | |
4438 | } | |
4439 | ||
3fc32f40 AN |
4440 | static bool core_relo_is_type_based(enum bpf_core_relo_kind kind) |
4441 | { | |
4442 | switch (kind) { | |
4443 | case BPF_TYPE_ID_LOCAL: | |
4444 | case BPF_TYPE_ID_TARGET: | |
4445 | case BPF_TYPE_EXISTS: | |
4446 | case BPF_TYPE_SIZE: | |
4447 | return true; | |
4448 | default: | |
4449 | return false; | |
4450 | } | |
4451 | } | |
4452 | ||
eacaaed7 AN |
4453 | static bool core_relo_is_enumval_based(enum bpf_core_relo_kind kind) |
4454 | { | |
4455 | switch (kind) { | |
4456 | case BPF_ENUMVAL_EXISTS: | |
4457 | case BPF_ENUMVAL_VALUE: | |
4458 | return true; | |
4459 | default: | |
4460 | return false; | |
4461 | } | |
4462 | } | |
4463 | ||
ddc7c304 | 4464 | /* |
28b93c64 | 4465 | * Turn bpf_core_relo into a low- and high-level spec representation, |
ddc7c304 | 4466 | * validating correctness along the way, as well as calculating resulting |
ee26dade AN |
4467 | * field bit offset, specified by accessor string. Low-level spec captures |
4468 | * every single level of nestedness, including traversing anonymous | |
ddc7c304 AN |
4469 | * struct/union members. High-level one only captures semantically meaningful |
4470 | * "turning points": named fields and array indicies. | |
4471 | * E.g., for this case: | |
4472 | * | |
4473 | * struct sample { | |
4474 | * int __unimportant; | |
4475 | * struct { | |
4476 | * int __1; | |
4477 | * int __2; | |
4478 | * int a[7]; | |
4479 | * }; | |
4480 | * }; | |
4481 | * | |
4482 | * struct sample *s = ...; | |
4483 | * | |
4484 | * int x = &s->a[3]; // access string = '0:1:2:3' | |
4485 | * | |
4486 | * Low-level spec has 1:1 mapping with each element of access string (it's | |
4487 | * just a parsed access string representation): [0, 1, 2, 3]. | |
4488 | * | |
4489 | * High-level spec will capture only 3 points: | |
4490 | * - intial zero-index access by pointer (&s->... is the same as &s[0]...); | |
4491 | * - field 'a' access (corresponds to '2' in low-level spec); | |
4492 | * - array element #3 access (corresponds to '3' in low-level spec). | |
4493 | * | |
3fc32f40 AN |
4494 | * Type-based relocations (TYPE_EXISTS/TYPE_SIZE, |
4495 | * TYPE_ID_LOCAL/TYPE_ID_TARGET) don't capture any field information. Their | |
4496 | * spec and raw_spec are kept empty. | |
eacaaed7 AN |
4497 | * |
4498 | * Enum value-based relocations (ENUMVAL_EXISTS/ENUMVAL_VALUE) use access | |
4499 | * string to specify enumerator's value index that need to be relocated. | |
ddc7c304 | 4500 | */ |
28b93c64 | 4501 | static int bpf_core_parse_spec(const struct btf *btf, |
ddc7c304 AN |
4502 | __u32 type_id, |
4503 | const char *spec_str, | |
28b93c64 | 4504 | enum bpf_core_relo_kind relo_kind, |
ddc7c304 AN |
4505 | struct bpf_core_spec *spec) |
4506 | { | |
4507 | int access_idx, parsed_len, i; | |
1b484b30 | 4508 | struct bpf_core_accessor *acc; |
ddc7c304 AN |
4509 | const struct btf_type *t; |
4510 | const char *name; | |
4511 | __u32 id; | |
4512 | __s64 sz; | |
4513 | ||
4514 | if (str_is_empty(spec_str) || *spec_str == ':') | |
4515 | return -EINVAL; | |
4516 | ||
4517 | memset(spec, 0, sizeof(*spec)); | |
4518 | spec->btf = btf; | |
28b93c64 AN |
4519 | spec->root_type_id = type_id; |
4520 | spec->relo_kind = relo_kind; | |
ddc7c304 | 4521 | |
3fc32f40 AN |
4522 | /* type-based relocations don't have a field access string */ |
4523 | if (core_relo_is_type_based(relo_kind)) { | |
4524 | if (strcmp(spec_str, "0")) | |
4525 | return -EINVAL; | |
4526 | return 0; | |
4527 | } | |
4528 | ||
ddc7c304 AN |
4529 | /* parse spec_str="0:1:2:3:4" into array raw_spec=[0, 1, 2, 3, 4] */ |
4530 | while (*spec_str) { | |
4531 | if (*spec_str == ':') | |
4532 | ++spec_str; | |
4533 | if (sscanf(spec_str, "%d%n", &access_idx, &parsed_len) != 1) | |
4534 | return -EINVAL; | |
4535 | if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN) | |
4536 | return -E2BIG; | |
4537 | spec_str += parsed_len; | |
4538 | spec->raw_spec[spec->raw_len++] = access_idx; | |
4539 | } | |
4540 | ||
4541 | if (spec->raw_len == 0) | |
4542 | return -EINVAL; | |
4543 | ||
ddc7c304 AN |
4544 | t = skip_mods_and_typedefs(btf, type_id, &id); |
4545 | if (!t) | |
4546 | return -EINVAL; | |
4547 | ||
4548 | access_idx = spec->raw_spec[0]; | |
eacaaed7 AN |
4549 | acc = &spec->spec[0]; |
4550 | acc->type_id = id; | |
4551 | acc->idx = access_idx; | |
ddc7c304 AN |
4552 | spec->len++; |
4553 | ||
eacaaed7 AN |
4554 | if (core_relo_is_enumval_based(relo_kind)) { |
4555 | if (!btf_is_enum(t) || spec->raw_len > 1 || access_idx >= btf_vlen(t)) | |
4556 | return -EINVAL; | |
4557 | ||
4558 | /* record enumerator name in a first accessor */ | |
4559 | acc->name = btf__name_by_offset(btf, btf_enum(t)[access_idx].name_off); | |
4560 | return 0; | |
4561 | } | |
4562 | ||
28b93c64 AN |
4563 | if (!core_relo_is_field_based(relo_kind)) |
4564 | return -EINVAL; | |
4565 | ||
ddc7c304 AN |
4566 | sz = btf__resolve_size(btf, id); |
4567 | if (sz < 0) | |
4568 | return sz; | |
ee26dade | 4569 | spec->bit_offset = access_idx * sz * 8; |
ddc7c304 AN |
4570 | |
4571 | for (i = 1; i < spec->raw_len; i++) { | |
4572 | t = skip_mods_and_typedefs(btf, id, &id); | |
4573 | if (!t) | |
4574 | return -EINVAL; | |
4575 | ||
4576 | access_idx = spec->raw_spec[i]; | |
1b484b30 | 4577 | acc = &spec->spec[spec->len]; |
ddc7c304 AN |
4578 | |
4579 | if (btf_is_composite(t)) { | |
4580 | const struct btf_member *m; | |
ee26dade | 4581 | __u32 bit_offset; |
ddc7c304 AN |
4582 | |
4583 | if (access_idx >= btf_vlen(t)) | |
4584 | return -EINVAL; | |
ddc7c304 | 4585 | |
ee26dade AN |
4586 | bit_offset = btf_member_bit_offset(t, access_idx); |
4587 | spec->bit_offset += bit_offset; | |
ddc7c304 AN |
4588 | |
4589 | m = btf_members(t) + access_idx; | |
4590 | if (m->name_off) { | |
4591 | name = btf__name_by_offset(btf, m->name_off); | |
4592 | if (str_is_empty(name)) | |
4593 | return -EINVAL; | |
4594 | ||
1b484b30 AN |
4595 | acc->type_id = id; |
4596 | acc->idx = access_idx; | |
4597 | acc->name = name; | |
ddc7c304 AN |
4598 | spec->len++; |
4599 | } | |
4600 | ||
4601 | id = m->type; | |
4602 | } else if (btf_is_array(t)) { | |
4603 | const struct btf_array *a = btf_array(t); | |
1b484b30 | 4604 | bool flex; |
ddc7c304 AN |
4605 | |
4606 | t = skip_mods_and_typedefs(btf, a->type, &id); | |
1b484b30 AN |
4607 | if (!t) |
4608 | return -EINVAL; | |
4609 | ||
4610 | flex = is_flex_arr(btf, acc - 1, a); | |
4611 | if (!flex && access_idx >= a->nelems) | |
ddc7c304 AN |
4612 | return -EINVAL; |
4613 | ||
4614 | spec->spec[spec->len].type_id = id; | |
4615 | spec->spec[spec->len].idx = access_idx; | |
4616 | spec->len++; | |
4617 | ||
4618 | sz = btf__resolve_size(btf, id); | |
4619 | if (sz < 0) | |
4620 | return sz; | |
ee26dade | 4621 | spec->bit_offset += access_idx * sz * 8; |
ddc7c304 | 4622 | } else { |
81ba0889 AN |
4623 | pr_warn("relo for [%u] %s (at idx %d) captures type [%d] of unexpected kind %s\n", |
4624 | type_id, spec_str, i, id, btf_kind_str(t)); | |
ddc7c304 AN |
4625 | return -EINVAL; |
4626 | } | |
4627 | } | |
4628 | ||
4629 | return 0; | |
4630 | } | |
4631 | ||
4632 | static bool bpf_core_is_flavor_sep(const char *s) | |
4633 | { | |
4634 | /* check X___Y name pattern, where X and Y are not underscores */ | |
4635 | return s[0] != '_' && /* X */ | |
4636 | s[1] == '_' && s[2] == '_' && s[3] == '_' && /* ___ */ | |
4637 | s[4] != '_'; /* Y */ | |
4638 | } | |
4639 | ||
4640 | /* Given 'some_struct_name___with_flavor' return the length of a name prefix | |
4641 | * before last triple underscore. Struct name part after last triple | |
4642 | * underscore is ignored by BPF CO-RE relocation during relocation matching. | |
4643 | */ | |
4644 | static size_t bpf_core_essential_name_len(const char *name) | |
4645 | { | |
4646 | size_t n = strlen(name); | |
4647 | int i; | |
4648 | ||
4649 | for (i = n - 5; i >= 0; i--) { | |
4650 | if (bpf_core_is_flavor_sep(name + i)) | |
4651 | return i + 1; | |
4652 | } | |
4653 | return n; | |
4654 | } | |
4655 | ||
0f7515ca AN |
4656 | struct core_cand |
4657 | { | |
4658 | const struct btf *btf; | |
4659 | const struct btf_type *t; | |
4660 | const char *name; | |
4661 | __u32 id; | |
4662 | }; | |
4663 | ||
4664 | /* dynamically sized list of type IDs and its associated struct btf */ | |
4665 | struct core_cand_list { | |
4666 | struct core_cand *cands; | |
ddc7c304 AN |
4667 | int len; |
4668 | }; | |
4669 | ||
0f7515ca | 4670 | static void bpf_core_free_cands(struct core_cand_list *cands) |
ddc7c304 | 4671 | { |
0f7515ca AN |
4672 | free(cands->cands); |
4673 | free(cands); | |
ddc7c304 AN |
4674 | } |
4675 | ||
0f7515ca AN |
4676 | static int bpf_core_add_cands(struct core_cand *local_cand, |
4677 | size_t local_essent_len, | |
4678 | const struct btf *targ_btf, | |
4679 | const char *targ_btf_name, | |
4680 | int targ_start_id, | |
4681 | struct core_cand_list *cands) | |
ddc7c304 | 4682 | { |
0f7515ca AN |
4683 | struct core_cand *new_cands, *cand; |
4684 | const struct btf_type *t; | |
4685 | const char *targ_name; | |
4686 | size_t targ_essent_len; | |
4687 | int n, i; | |
ddc7c304 AN |
4688 | |
4689 | n = btf__get_nr_types(targ_btf); | |
0f7515ca | 4690 | for (i = targ_start_id; i <= n; i++) { |
ddc7c304 | 4691 | t = btf__type_by_id(targ_btf, i); |
0f7515ca | 4692 | if (btf_kind(t) != btf_kind(local_cand->t)) |
ddc7c304 AN |
4693 | continue; |
4694 | ||
3fc32f40 AN |
4695 | targ_name = btf__name_by_offset(targ_btf, t->name_off); |
4696 | if (str_is_empty(targ_name)) | |
d121e1d3 AN |
4697 | continue; |
4698 | ||
ddc7c304 AN |
4699 | targ_essent_len = bpf_core_essential_name_len(targ_name); |
4700 | if (targ_essent_len != local_essent_len) | |
4701 | continue; | |
4702 | ||
0f7515ca AN |
4703 | if (strncmp(local_cand->name, targ_name, local_essent_len) != 0) |
4704 | continue; | |
4705 | ||
4706 | pr_debug("CO-RE relocating [%d] %s %s: found target candidate [%d] %s %s in [%s]\n", | |
4707 | local_cand->id, btf_kind_str(local_cand->t), | |
4708 | local_cand->name, i, btf_kind_str(t), targ_name, | |
4709 | targ_btf_name); | |
4710 | new_cands = libbpf_reallocarray(cands->cands, cands->len + 1, | |
4711 | sizeof(*cands->cands)); | |
4712 | if (!new_cands) | |
4713 | return -ENOMEM; | |
4714 | ||
4715 | cand = &new_cands[cands->len]; | |
4716 | cand->btf = targ_btf; | |
4717 | cand->t = t; | |
4718 | cand->name = targ_name; | |
4719 | cand->id = i; | |
4720 | ||
4721 | cands->cands = new_cands; | |
4722 | cands->len++; | |
ddc7c304 | 4723 | } |
0f7515ca AN |
4724 | return 0; |
4725 | } | |
4726 | ||
4f33a53d AN |
4727 | static int load_module_btfs(struct bpf_object *obj) |
4728 | { | |
4729 | struct bpf_btf_info info; | |
4730 | struct module_btf *mod_btf; | |
4731 | struct btf *btf; | |
4732 | char name[64]; | |
4733 | __u32 id = 0, len; | |
4734 | int err, fd; | |
4735 | ||
4736 | if (obj->btf_modules_loaded) | |
4737 | return 0; | |
4738 | ||
4739 | /* don't do this again, even if we find no module BTFs */ | |
4740 | obj->btf_modules_loaded = true; | |
4741 | ||
4742 | /* kernel too old to support module BTFs */ | |
4743 | if (!kernel_supports(FEAT_MODULE_BTF)) | |
4744 | return 0; | |
4745 | ||
4746 | while (true) { | |
4747 | err = bpf_btf_get_next_id(id, &id); | |
4748 | if (err && errno == ENOENT) | |
4749 | return 0; | |
4750 | if (err) { | |
4751 | err = -errno; | |
4752 | pr_warn("failed to iterate BTF objects: %d\n", err); | |
4753 | return err; | |
ddc7c304 | 4754 | } |
4f33a53d AN |
4755 | |
4756 | fd = bpf_btf_get_fd_by_id(id); | |
4757 | if (fd < 0) { | |
4758 | if (errno == ENOENT) | |
4759 | continue; /* expected race: BTF was unloaded */ | |
4760 | err = -errno; | |
4761 | pr_warn("failed to get BTF object #%d FD: %d\n", id, err); | |
4762 | return err; | |
4763 | } | |
4764 | ||
4765 | len = sizeof(info); | |
4766 | memset(&info, 0, sizeof(info)); | |
4767 | info.name = ptr_to_u64(name); | |
4768 | info.name_len = sizeof(name); | |
4769 | ||
4770 | err = bpf_obj_get_info_by_fd(fd, &info, &len); | |
4771 | if (err) { | |
4772 | err = -errno; | |
4773 | pr_warn("failed to get BTF object #%d info: %d\n", id, err); | |
91abb4a6 | 4774 | goto err_out; |
4f33a53d AN |
4775 | } |
4776 | ||
4777 | /* ignore non-module BTFs */ | |
4778 | if (!info.kernel_btf || strcmp(name, "vmlinux") == 0) { | |
4779 | close(fd); | |
4780 | continue; | |
4781 | } | |
4782 | ||
4783 | btf = btf_get_from_fd(fd, obj->btf_vmlinux); | |
4f33a53d AN |
4784 | if (IS_ERR(btf)) { |
4785 | pr_warn("failed to load module [%s]'s BTF object #%d: %ld\n", | |
4786 | name, id, PTR_ERR(btf)); | |
91abb4a6 AN |
4787 | err = PTR_ERR(btf); |
4788 | goto err_out; | |
4f33a53d AN |
4789 | } |
4790 | ||
4791 | err = btf_ensure_mem((void **)&obj->btf_modules, &obj->btf_module_cap, | |
4792 | sizeof(*obj->btf_modules), obj->btf_module_cnt + 1); | |
4793 | if (err) | |
91abb4a6 | 4794 | goto err_out; |
4f33a53d AN |
4795 | |
4796 | mod_btf = &obj->btf_modules[obj->btf_module_cnt++]; | |
4797 | ||
4798 | mod_btf->btf = btf; | |
4799 | mod_btf->id = id; | |
91abb4a6 | 4800 | mod_btf->fd = fd; |
4f33a53d | 4801 | mod_btf->name = strdup(name); |
91abb4a6 AN |
4802 | if (!mod_btf->name) { |
4803 | err = -ENOMEM; | |
4804 | goto err_out; | |
4805 | } | |
4806 | continue; | |
4807 | ||
4808 | err_out: | |
4809 | close(fd); | |
4810 | return err; | |
ddc7c304 | 4811 | } |
4f33a53d AN |
4812 | |
4813 | return 0; | |
4814 | } | |
4815 | ||
0f7515ca AN |
4816 | static struct core_cand_list * |
4817 | bpf_core_find_cands(struct bpf_object *obj, const struct btf *local_btf, __u32 local_type_id) | |
4818 | { | |
4819 | struct core_cand local_cand = {}; | |
4820 | struct core_cand_list *cands; | |
4f33a53d | 4821 | const struct btf *main_btf; |
0f7515ca | 4822 | size_t local_essent_len; |
4f33a53d | 4823 | int err, i; |
0f7515ca AN |
4824 | |
4825 | local_cand.btf = local_btf; | |
4826 | local_cand.t = btf__type_by_id(local_btf, local_type_id); | |
4827 | if (!local_cand.t) | |
4828 | return ERR_PTR(-EINVAL); | |
4829 | ||
4830 | local_cand.name = btf__name_by_offset(local_btf, local_cand.t->name_off); | |
4831 | if (str_is_empty(local_cand.name)) | |
4832 | return ERR_PTR(-EINVAL); | |
4833 | local_essent_len = bpf_core_essential_name_len(local_cand.name); | |
4834 | ||
4835 | cands = calloc(1, sizeof(*cands)); | |
4836 | if (!cands) | |
4837 | return ERR_PTR(-ENOMEM); | |
4838 | ||
4839 | /* Attempt to find target candidates in vmlinux BTF first */ | |
4f33a53d AN |
4840 | main_btf = obj->btf_vmlinux_override ?: obj->btf_vmlinux; |
4841 | err = bpf_core_add_cands(&local_cand, local_essent_len, main_btf, "vmlinux", 1, cands); | |
4842 | if (err) | |
4843 | goto err_out; | |
4844 | ||
4845 | /* if vmlinux BTF has any candidate, don't got for module BTFs */ | |
4846 | if (cands->len) | |
4847 | return cands; | |
4848 | ||
4849 | /* if vmlinux BTF was overridden, don't attempt to load module BTFs */ | |
4850 | if (obj->btf_vmlinux_override) | |
4851 | return cands; | |
4852 | ||
4853 | /* now look through module BTFs, trying to still find candidates */ | |
4854 | err = load_module_btfs(obj); | |
4855 | if (err) | |
4856 | goto err_out; | |
4857 | ||
4858 | for (i = 0; i < obj->btf_module_cnt; i++) { | |
4859 | err = bpf_core_add_cands(&local_cand, local_essent_len, | |
4860 | obj->btf_modules[i].btf, | |
4861 | obj->btf_modules[i].name, | |
4862 | btf__get_nr_types(obj->btf_vmlinux) + 1, | |
4863 | cands); | |
4864 | if (err) | |
4865 | goto err_out; | |
0f7515ca AN |
4866 | } |
4867 | ||
4868 | return cands; | |
ddc7c304 | 4869 | err_out: |
4f33a53d | 4870 | bpf_core_free_cands(cands); |
ddc7c304 AN |
4871 | return ERR_PTR(err); |
4872 | } | |
4873 | ||
3fc32f40 AN |
4874 | /* Check two types for compatibility for the purpose of field access |
4875 | * relocation. const/volatile/restrict and typedefs are skipped to ensure we | |
4876 | * are relocating semantically compatible entities: | |
ddc7c304 | 4877 | * - any two STRUCTs/UNIONs are compatible and can be mixed; |
94f060e9 | 4878 | * - any two FWDs are compatible, if their names match (modulo flavor suffix); |
ddc7c304 | 4879 | * - any two PTRs are always compatible; |
94f060e9 AN |
4880 | * - for ENUMs, names should be the same (ignoring flavor suffix) or at |
4881 | * least one of enums should be anonymous; | |
ddc7c304 | 4882 | * - for ENUMs, check sizes, names are ignored; |
ee26dade | 4883 | * - for INT, size and signedness are ignored; |
ddc7c304 AN |
4884 | * - for ARRAY, dimensionality is ignored, element types are checked for |
4885 | * compatibility recursively; | |
4886 | * - everything else shouldn't be ever a target of relocation. | |
4887 | * These rules are not set in stone and probably will be adjusted as we get | |
4888 | * more experience with using BPF CO-RE relocations. | |
4889 | */ | |
4890 | static int bpf_core_fields_are_compat(const struct btf *local_btf, | |
4891 | __u32 local_id, | |
4892 | const struct btf *targ_btf, | |
4893 | __u32 targ_id) | |
4894 | { | |
4895 | const struct btf_type *local_type, *targ_type; | |
4896 | ||
4897 | recur: | |
4898 | local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id); | |
4899 | targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); | |
4900 | if (!local_type || !targ_type) | |
4901 | return -EINVAL; | |
4902 | ||
4903 | if (btf_is_composite(local_type) && btf_is_composite(targ_type)) | |
4904 | return 1; | |
4905 | if (btf_kind(local_type) != btf_kind(targ_type)) | |
4906 | return 0; | |
4907 | ||
4908 | switch (btf_kind(local_type)) { | |
ddc7c304 AN |
4909 | case BTF_KIND_PTR: |
4910 | return 1; | |
94f060e9 AN |
4911 | case BTF_KIND_FWD: |
4912 | case BTF_KIND_ENUM: { | |
4913 | const char *local_name, *targ_name; | |
4914 | size_t local_len, targ_len; | |
4915 | ||
4916 | local_name = btf__name_by_offset(local_btf, | |
4917 | local_type->name_off); | |
4918 | targ_name = btf__name_by_offset(targ_btf, targ_type->name_off); | |
4919 | local_len = bpf_core_essential_name_len(local_name); | |
4920 | targ_len = bpf_core_essential_name_len(targ_name); | |
4921 | /* one of them is anonymous or both w/ same flavor-less names */ | |
4922 | return local_len == 0 || targ_len == 0 || | |
4923 | (local_len == targ_len && | |
4924 | strncmp(local_name, targ_name, local_len) == 0); | |
4925 | } | |
ddc7c304 | 4926 | case BTF_KIND_INT: |
ee26dade AN |
4927 | /* just reject deprecated bitfield-like integers; all other |
4928 | * integers are by default compatible between each other | |
4929 | */ | |
ddc7c304 | 4930 | return btf_int_offset(local_type) == 0 && |
ee26dade | 4931 | btf_int_offset(targ_type) == 0; |
ddc7c304 AN |
4932 | case BTF_KIND_ARRAY: |
4933 | local_id = btf_array(local_type)->type; | |
4934 | targ_id = btf_array(targ_type)->type; | |
4935 | goto recur; | |
4936 | default: | |
be18010e KW |
4937 | pr_warn("unexpected kind %d relocated, local [%d], target [%d]\n", |
4938 | btf_kind(local_type), local_id, targ_id); | |
ddc7c304 AN |
4939 | return 0; |
4940 | } | |
4941 | } | |
4942 | ||
4943 | /* | |
4944 | * Given single high-level named field accessor in local type, find | |
4945 | * corresponding high-level accessor for a target type. Along the way, | |
4946 | * maintain low-level spec for target as well. Also keep updating target | |
ee26dade | 4947 | * bit offset. |
ddc7c304 AN |
4948 | * |
4949 | * Searching is performed through recursive exhaustive enumeration of all | |
4950 | * fields of a struct/union. If there are any anonymous (embedded) | |
4951 | * structs/unions, they are recursively searched as well. If field with | |
4952 | * desired name is found, check compatibility between local and target types, | |
4953 | * before returning result. | |
4954 | * | |
4955 | * 1 is returned, if field is found. | |
4956 | * 0 is returned if no compatible field is found. | |
4957 | * <0 is returned on error. | |
4958 | */ | |
4959 | static int bpf_core_match_member(const struct btf *local_btf, | |
4960 | const struct bpf_core_accessor *local_acc, | |
4961 | const struct btf *targ_btf, | |
4962 | __u32 targ_id, | |
4963 | struct bpf_core_spec *spec, | |
4964 | __u32 *next_targ_id) | |
4965 | { | |
4966 | const struct btf_type *local_type, *targ_type; | |
4967 | const struct btf_member *local_member, *m; | |
4968 | const char *local_name, *targ_name; | |
4969 | __u32 local_id; | |
4970 | int i, n, found; | |
4971 | ||
4972 | targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); | |
4973 | if (!targ_type) | |
4974 | return -EINVAL; | |
4975 | if (!btf_is_composite(targ_type)) | |
4976 | return 0; | |
4977 | ||
4978 | local_id = local_acc->type_id; | |
4979 | local_type = btf__type_by_id(local_btf, local_id); | |
4980 | local_member = btf_members(local_type) + local_acc->idx; | |
4981 | local_name = btf__name_by_offset(local_btf, local_member->name_off); | |
4982 | ||
4983 | n = btf_vlen(targ_type); | |
4984 | m = btf_members(targ_type); | |
4985 | for (i = 0; i < n; i++, m++) { | |
ee26dade | 4986 | __u32 bit_offset; |
ddc7c304 | 4987 | |
ee26dade | 4988 | bit_offset = btf_member_bit_offset(targ_type, i); |
ddc7c304 AN |
4989 | |
4990 | /* too deep struct/union/array nesting */ | |
4991 | if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN) | |
4992 | return -E2BIG; | |
4993 | ||
4994 | /* speculate this member will be the good one */ | |
ee26dade | 4995 | spec->bit_offset += bit_offset; |
ddc7c304 AN |
4996 | spec->raw_spec[spec->raw_len++] = i; |
4997 | ||
4998 | targ_name = btf__name_by_offset(targ_btf, m->name_off); | |
4999 | if (str_is_empty(targ_name)) { | |
5000 | /* embedded struct/union, we need to go deeper */ | |
5001 | found = bpf_core_match_member(local_btf, local_acc, | |
5002 | targ_btf, m->type, | |
5003 | spec, next_targ_id); | |
5004 | if (found) /* either found or error */ | |
5005 | return found; | |
5006 | } else if (strcmp(local_name, targ_name) == 0) { | |
5007 | /* matching named field */ | |
5008 | struct bpf_core_accessor *targ_acc; | |
5009 | ||
5010 | targ_acc = &spec->spec[spec->len++]; | |
5011 | targ_acc->type_id = targ_id; | |
5012 | targ_acc->idx = i; | |
5013 | targ_acc->name = targ_name; | |
5014 | ||
5015 | *next_targ_id = m->type; | |
5016 | found = bpf_core_fields_are_compat(local_btf, | |
5017 | local_member->type, | |
5018 | targ_btf, m->type); | |
5019 | if (!found) | |
5020 | spec->len--; /* pop accessor */ | |
5021 | return found; | |
5022 | } | |
5023 | /* member turned out not to be what we looked for */ | |
ee26dade | 5024 | spec->bit_offset -= bit_offset; |
ddc7c304 AN |
5025 | spec->raw_len--; |
5026 | } | |
5027 | ||
5028 | return 0; | |
5029 | } | |
5030 | ||
3fc32f40 AN |
5031 | /* Check local and target types for compatibility. This check is used for |
5032 | * type-based CO-RE relocations and follow slightly different rules than | |
5033 | * field-based relocations. This function assumes that root types were already | |
5034 | * checked for name match. Beyond that initial root-level name check, names | |
5035 | * are completely ignored. Compatibility rules are as follows: | |
5036 | * - any two STRUCTs/UNIONs/FWDs/ENUMs/INTs are considered compatible, but | |
5037 | * kind should match for local and target types (i.e., STRUCT is not | |
5038 | * compatible with UNION); | |
5039 | * - for ENUMs, the size is ignored; | |
5040 | * - for INT, size and signedness are ignored; | |
5041 | * - for ARRAY, dimensionality is ignored, element types are checked for | |
5042 | * compatibility recursively; | |
5043 | * - CONST/VOLATILE/RESTRICT modifiers are ignored; | |
5044 | * - TYPEDEFs/PTRs are compatible if types they pointing to are compatible; | |
5045 | * - FUNC_PROTOs are compatible if they have compatible signature: same | |
5046 | * number of input args and compatible return and argument types. | |
5047 | * These rules are not set in stone and probably will be adjusted as we get | |
5048 | * more experience with using BPF CO-RE relocations. | |
5049 | */ | |
5050 | static int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id, | |
5051 | const struct btf *targ_btf, __u32 targ_id) | |
5052 | { | |
5053 | const struct btf_type *local_type, *targ_type; | |
5054 | int depth = 32; /* max recursion depth */ | |
5055 | ||
5056 | /* caller made sure that names match (ignoring flavor suffix) */ | |
5057 | local_type = btf__type_by_id(local_btf, local_id); | |
f872e4bc | 5058 | targ_type = btf__type_by_id(targ_btf, targ_id); |
3fc32f40 AN |
5059 | if (btf_kind(local_type) != btf_kind(targ_type)) |
5060 | return 0; | |
5061 | ||
5062 | recur: | |
5063 | depth--; | |
5064 | if (depth < 0) | |
5065 | return -EINVAL; | |
5066 | ||
5067 | local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id); | |
5068 | targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); | |
5069 | if (!local_type || !targ_type) | |
5070 | return -EINVAL; | |
5071 | ||
5072 | if (btf_kind(local_type) != btf_kind(targ_type)) | |
5073 | return 0; | |
5074 | ||
5075 | switch (btf_kind(local_type)) { | |
5076 | case BTF_KIND_UNKN: | |
5077 | case BTF_KIND_STRUCT: | |
5078 | case BTF_KIND_UNION: | |
5079 | case BTF_KIND_ENUM: | |
5080 | case BTF_KIND_FWD: | |
5081 | return 1; | |
5082 | case BTF_KIND_INT: | |
5083 | /* just reject deprecated bitfield-like integers; all other | |
5084 | * integers are by default compatible between each other | |
5085 | */ | |
5086 | return btf_int_offset(local_type) == 0 && btf_int_offset(targ_type) == 0; | |
5087 | case BTF_KIND_PTR: | |
5088 | local_id = local_type->type; | |
5089 | targ_id = targ_type->type; | |
5090 | goto recur; | |
5091 | case BTF_KIND_ARRAY: | |
5092 | local_id = btf_array(local_type)->type; | |
5093 | targ_id = btf_array(targ_type)->type; | |
5094 | goto recur; | |
5095 | case BTF_KIND_FUNC_PROTO: { | |
5096 | struct btf_param *local_p = btf_params(local_type); | |
5097 | struct btf_param *targ_p = btf_params(targ_type); | |
5098 | __u16 local_vlen = btf_vlen(local_type); | |
5099 | __u16 targ_vlen = btf_vlen(targ_type); | |
5100 | int i, err; | |
5101 | ||
5102 | if (local_vlen != targ_vlen) | |
5103 | return 0; | |
5104 | ||
5105 | for (i = 0; i < local_vlen; i++, local_p++, targ_p++) { | |
5106 | skip_mods_and_typedefs(local_btf, local_p->type, &local_id); | |
5107 | skip_mods_and_typedefs(targ_btf, targ_p->type, &targ_id); | |
5108 | err = bpf_core_types_are_compat(local_btf, local_id, targ_btf, targ_id); | |
5109 | if (err <= 0) | |
5110 | return err; | |
5111 | } | |
5112 | ||
5113 | /* tail recurse for return type check */ | |
5114 | skip_mods_and_typedefs(local_btf, local_type->type, &local_id); | |
5115 | skip_mods_and_typedefs(targ_btf, targ_type->type, &targ_id); | |
5116 | goto recur; | |
5117 | } | |
5118 | default: | |
5119 | pr_warn("unexpected kind %s relocated, local [%d], target [%d]\n", | |
5120 | btf_kind_str(local_type), local_id, targ_id); | |
5121 | return 0; | |
5122 | } | |
5123 | } | |
5124 | ||
ddc7c304 AN |
5125 | /* |
5126 | * Try to match local spec to a target type and, if successful, produce full | |
ee26dade | 5127 | * target spec (high-level, low-level + bit offset). |
ddc7c304 AN |
5128 | */ |
5129 | static int bpf_core_spec_match(struct bpf_core_spec *local_spec, | |
5130 | const struct btf *targ_btf, __u32 targ_id, | |
5131 | struct bpf_core_spec *targ_spec) | |
5132 | { | |
5133 | const struct btf_type *targ_type; | |
5134 | const struct bpf_core_accessor *local_acc; | |
5135 | struct bpf_core_accessor *targ_acc; | |
5136 | int i, sz, matched; | |
5137 | ||
5138 | memset(targ_spec, 0, sizeof(*targ_spec)); | |
5139 | targ_spec->btf = targ_btf; | |
28b93c64 AN |
5140 | targ_spec->root_type_id = targ_id; |
5141 | targ_spec->relo_kind = local_spec->relo_kind; | |
ddc7c304 | 5142 | |
3fc32f40 AN |
5143 | if (core_relo_is_type_based(local_spec->relo_kind)) { |
5144 | return bpf_core_types_are_compat(local_spec->btf, | |
5145 | local_spec->root_type_id, | |
5146 | targ_btf, targ_id); | |
5147 | } | |
5148 | ||
ddc7c304 AN |
5149 | local_acc = &local_spec->spec[0]; |
5150 | targ_acc = &targ_spec->spec[0]; | |
5151 | ||
eacaaed7 AN |
5152 | if (core_relo_is_enumval_based(local_spec->relo_kind)) { |
5153 | size_t local_essent_len, targ_essent_len; | |
5154 | const struct btf_enum *e; | |
5155 | const char *targ_name; | |
5156 | ||
5157 | /* has to resolve to an enum */ | |
5158 | targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id, &targ_id); | |
5159 | if (!btf_is_enum(targ_type)) | |
5160 | return 0; | |
5161 | ||
5162 | local_essent_len = bpf_core_essential_name_len(local_acc->name); | |
5163 | ||
5164 | for (i = 0, e = btf_enum(targ_type); i < btf_vlen(targ_type); i++, e++) { | |
5165 | targ_name = btf__name_by_offset(targ_spec->btf, e->name_off); | |
5166 | targ_essent_len = bpf_core_essential_name_len(targ_name); | |
5167 | if (targ_essent_len != local_essent_len) | |
5168 | continue; | |
5169 | if (strncmp(local_acc->name, targ_name, local_essent_len) == 0) { | |
5170 | targ_acc->type_id = targ_id; | |
5171 | targ_acc->idx = i; | |
5172 | targ_acc->name = targ_name; | |
5173 | targ_spec->len++; | |
5174 | targ_spec->raw_spec[targ_spec->raw_len] = targ_acc->idx; | |
5175 | targ_spec->raw_len++; | |
5176 | return 1; | |
5177 | } | |
5178 | } | |
5179 | return 0; | |
5180 | } | |
5181 | ||
5182 | if (!core_relo_is_field_based(local_spec->relo_kind)) | |
5183 | return -EINVAL; | |
5184 | ||
ddc7c304 AN |
5185 | for (i = 0; i < local_spec->len; i++, local_acc++, targ_acc++) { |
5186 | targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id, | |
5187 | &targ_id); | |
5188 | if (!targ_type) | |
5189 | return -EINVAL; | |
5190 | ||
5191 | if (local_acc->name) { | |
5192 | matched = bpf_core_match_member(local_spec->btf, | |
5193 | local_acc, | |
5194 | targ_btf, targ_id, | |
5195 | targ_spec, &targ_id); | |
5196 | if (matched <= 0) | |
5197 | return matched; | |
5198 | } else { | |
5199 | /* for i=0, targ_id is already treated as array element | |
5200 | * type (because it's the original struct), for others | |
5201 | * we should find array element type first | |
5202 | */ | |
5203 | if (i > 0) { | |
5204 | const struct btf_array *a; | |
1b484b30 | 5205 | bool flex; |
ddc7c304 AN |
5206 | |
5207 | if (!btf_is_array(targ_type)) | |
5208 | return 0; | |
5209 | ||
5210 | a = btf_array(targ_type); | |
1b484b30 AN |
5211 | flex = is_flex_arr(targ_btf, targ_acc - 1, a); |
5212 | if (!flex && local_acc->idx >= a->nelems) | |
ddc7c304 AN |
5213 | return 0; |
5214 | if (!skip_mods_and_typedefs(targ_btf, a->type, | |
5215 | &targ_id)) | |
5216 | return -EINVAL; | |
5217 | } | |
5218 | ||
5219 | /* too deep struct/union/array nesting */ | |
5220 | if (targ_spec->raw_len == BPF_CORE_SPEC_MAX_LEN) | |
5221 | return -E2BIG; | |
5222 | ||
5223 | targ_acc->type_id = targ_id; | |
5224 | targ_acc->idx = local_acc->idx; | |
5225 | targ_acc->name = NULL; | |
5226 | targ_spec->len++; | |
5227 | targ_spec->raw_spec[targ_spec->raw_len] = targ_acc->idx; | |
5228 | targ_spec->raw_len++; | |
5229 | ||
5230 | sz = btf__resolve_size(targ_btf, targ_id); | |
5231 | if (sz < 0) | |
5232 | return sz; | |
ee26dade | 5233 | targ_spec->bit_offset += local_acc->idx * sz * 8; |
ddc7c304 AN |
5234 | } |
5235 | } | |
5236 | ||
5237 | return 1; | |
5238 | } | |
5239 | ||
ee26dade | 5240 | static int bpf_core_calc_field_relo(const struct bpf_program *prog, |
28b93c64 | 5241 | const struct bpf_core_relo *relo, |
ee26dade | 5242 | const struct bpf_core_spec *spec, |
a66345bc AN |
5243 | __u32 *val, __u32 *field_sz, __u32 *type_id, |
5244 | bool *validate) | |
ee26dade | 5245 | { |
353c788c AN |
5246 | const struct bpf_core_accessor *acc; |
5247 | const struct btf_type *t; | |
a66345bc | 5248 | __u32 byte_off, byte_sz, bit_off, bit_sz, field_type_id; |
ee26dade AN |
5249 | const struct btf_member *m; |
5250 | const struct btf_type *mt; | |
5251 | bool bitfield; | |
94f060e9 | 5252 | __s64 sz; |
ee26dade | 5253 | |
a66345bc AN |
5254 | *field_sz = 0; |
5255 | ||
353c788c AN |
5256 | if (relo->kind == BPF_FIELD_EXISTS) { |
5257 | *val = spec ? 1 : 0; | |
5258 | return 0; | |
5259 | } | |
5260 | ||
5261 | if (!spec) | |
5262 | return -EUCLEAN; /* request instruction poisoning */ | |
5263 | ||
5264 | acc = &spec->spec[spec->len - 1]; | |
5265 | t = btf__type_by_id(spec->btf, acc->type_id); | |
5266 | ||
ee26dade AN |
5267 | /* a[n] accessor needs special handling */ |
5268 | if (!acc->name) { | |
94f060e9 AN |
5269 | if (relo->kind == BPF_FIELD_BYTE_OFFSET) { |
5270 | *val = spec->bit_offset / 8; | |
a66345bc AN |
5271 | /* remember field size for load/store mem size */ |
5272 | sz = btf__resolve_size(spec->btf, acc->type_id); | |
5273 | if (sz < 0) | |
5274 | return -EINVAL; | |
5275 | *field_sz = sz; | |
5276 | *type_id = acc->type_id; | |
94f060e9 AN |
5277 | } else if (relo->kind == BPF_FIELD_BYTE_SIZE) { |
5278 | sz = btf__resolve_size(spec->btf, acc->type_id); | |
5279 | if (sz < 0) | |
5280 | return -EINVAL; | |
5281 | *val = sz; | |
5282 | } else { | |
5283 | pr_warn("prog '%s': relo %d at insn #%d can't be applied to array access\n", | |
52109584 | 5284 | prog->name, relo->kind, relo->insn_off / 8); |
ee26dade AN |
5285 | return -EINVAL; |
5286 | } | |
ee26dade AN |
5287 | if (validate) |
5288 | *validate = true; | |
5289 | return 0; | |
5290 | } | |
5291 | ||
5292 | m = btf_members(t) + acc->idx; | |
a66345bc | 5293 | mt = skip_mods_and_typedefs(spec->btf, m->type, &field_type_id); |
ee26dade AN |
5294 | bit_off = spec->bit_offset; |
5295 | bit_sz = btf_member_bitfield_size(t, acc->idx); | |
5296 | ||
5297 | bitfield = bit_sz > 0; | |
5298 | if (bitfield) { | |
5299 | byte_sz = mt->size; | |
5300 | byte_off = bit_off / 8 / byte_sz * byte_sz; | |
5301 | /* figure out smallest int size necessary for bitfield load */ | |
5302 | while (bit_off + bit_sz - byte_off * 8 > byte_sz * 8) { | |
5303 | if (byte_sz >= 8) { | |
5304 | /* bitfield can't be read with 64-bit read */ | |
5305 | pr_warn("prog '%s': relo %d at insn #%d can't be satisfied for bitfield\n", | |
52109584 | 5306 | prog->name, relo->kind, relo->insn_off / 8); |
ee26dade AN |
5307 | return -E2BIG; |
5308 | } | |
5309 | byte_sz *= 2; | |
5310 | byte_off = bit_off / 8 / byte_sz * byte_sz; | |
5311 | } | |
5312 | } else { | |
a66345bc | 5313 | sz = btf__resolve_size(spec->btf, field_type_id); |
94f060e9 AN |
5314 | if (sz < 0) |
5315 | return -EINVAL; | |
5316 | byte_sz = sz; | |
ee26dade AN |
5317 | byte_off = spec->bit_offset / 8; |
5318 | bit_sz = byte_sz * 8; | |
5319 | } | |
5320 | ||
5321 | /* for bitfields, all the relocatable aspects are ambiguous and we | |
5322 | * might disagree with compiler, so turn off validation of expected | |
5323 | * value, except for signedness | |
5324 | */ | |
5325 | if (validate) | |
5326 | *validate = !bitfield; | |
5327 | ||
5328 | switch (relo->kind) { | |
5329 | case BPF_FIELD_BYTE_OFFSET: | |
5330 | *val = byte_off; | |
a66345bc AN |
5331 | if (!bitfield) { |
5332 | *field_sz = byte_sz; | |
5333 | *type_id = field_type_id; | |
5334 | } | |
ee26dade AN |
5335 | break; |
5336 | case BPF_FIELD_BYTE_SIZE: | |
5337 | *val = byte_sz; | |
5338 | break; | |
5339 | case BPF_FIELD_SIGNED: | |
5340 | /* enums will be assumed unsigned */ | |
5341 | *val = btf_is_enum(mt) || | |
5342 | (btf_int_encoding(mt) & BTF_INT_SIGNED); | |
5343 | if (validate) | |
5344 | *validate = true; /* signedness is never ambiguous */ | |
5345 | break; | |
5346 | case BPF_FIELD_LSHIFT_U64: | |
5347 | #if __BYTE_ORDER == __LITTLE_ENDIAN | |
5348 | *val = 64 - (bit_off + bit_sz - byte_off * 8); | |
5349 | #else | |
5350 | *val = (8 - byte_sz) * 8 + (bit_off - byte_off * 8); | |
5351 | #endif | |
5352 | break; | |
5353 | case BPF_FIELD_RSHIFT_U64: | |
5354 | *val = 64 - bit_sz; | |
5355 | if (validate) | |
5356 | *validate = true; /* right shift is never ambiguous */ | |
5357 | break; | |
5358 | case BPF_FIELD_EXISTS: | |
5359 | default: | |
353c788c | 5360 | return -EOPNOTSUPP; |
ee26dade AN |
5361 | } |
5362 | ||
5363 | return 0; | |
5364 | } | |
5365 | ||
3fc32f40 AN |
5366 | static int bpf_core_calc_type_relo(const struct bpf_core_relo *relo, |
5367 | const struct bpf_core_spec *spec, | |
5368 | __u32 *val) | |
5369 | { | |
5370 | __s64 sz; | |
5371 | ||
5372 | /* type-based relos return zero when target type is not found */ | |
5373 | if (!spec) { | |
5374 | *val = 0; | |
5375 | return 0; | |
5376 | } | |
5377 | ||
5378 | switch (relo->kind) { | |
5379 | case BPF_TYPE_ID_TARGET: | |
5380 | *val = spec->root_type_id; | |
5381 | break; | |
5382 | case BPF_TYPE_EXISTS: | |
5383 | *val = 1; | |
5384 | break; | |
5385 | case BPF_TYPE_SIZE: | |
5386 | sz = btf__resolve_size(spec->btf, spec->root_type_id); | |
5387 | if (sz < 0) | |
5388 | return -EINVAL; | |
5389 | *val = sz; | |
5390 | break; | |
5391 | case BPF_TYPE_ID_LOCAL: | |
5392 | /* BPF_TYPE_ID_LOCAL is handled specially and shouldn't get here */ | |
5393 | default: | |
5394 | return -EOPNOTSUPP; | |
5395 | } | |
5396 | ||
5397 | return 0; | |
5398 | } | |
5399 | ||
eacaaed7 AN |
5400 | static int bpf_core_calc_enumval_relo(const struct bpf_core_relo *relo, |
5401 | const struct bpf_core_spec *spec, | |
5402 | __u32 *val) | |
5403 | { | |
5404 | const struct btf_type *t; | |
5405 | const struct btf_enum *e; | |
5406 | ||
5407 | switch (relo->kind) { | |
5408 | case BPF_ENUMVAL_EXISTS: | |
5409 | *val = spec ? 1 : 0; | |
5410 | break; | |
5411 | case BPF_ENUMVAL_VALUE: | |
5412 | if (!spec) | |
5413 | return -EUCLEAN; /* request instruction poisoning */ | |
5414 | t = btf__type_by_id(spec->btf, spec->spec[0].type_id); | |
5415 | e = btf_enum(t) + spec->spec[0].idx; | |
5416 | *val = e->val; | |
5417 | break; | |
5418 | default: | |
5419 | return -EOPNOTSUPP; | |
5420 | } | |
5421 | ||
5422 | return 0; | |
5423 | } | |
5424 | ||
353c788c AN |
5425 | struct bpf_core_relo_res |
5426 | { | |
5427 | /* expected value in the instruction, unless validate == false */ | |
5428 | __u32 orig_val; | |
5429 | /* new value that needs to be patched up to */ | |
5430 | __u32 new_val; | |
5431 | /* relocation unsuccessful, poison instruction, but don't fail load */ | |
5432 | bool poison; | |
5433 | /* some relocations can't be validated against orig_val */ | |
5434 | bool validate; | |
a66345bc AN |
5435 | /* for field byte offset relocations or the forms: |
5436 | * *(T *)(rX + <off>) = rY | |
5437 | * rX = *(T *)(rY + <off>), | |
5438 | * we remember original and resolved field size to adjust direct | |
5439 | * memory loads of pointers and integers; this is necessary for 32-bit | |
5440 | * host kernel architectures, but also allows to automatically | |
5441 | * relocate fields that were resized from, e.g., u32 to u64, etc. | |
5442 | */ | |
5443 | bool fail_memsz_adjust; | |
5444 | __u32 orig_sz; | |
5445 | __u32 orig_type_id; | |
5446 | __u32 new_sz; | |
5447 | __u32 new_type_id; | |
353c788c AN |
5448 | }; |
5449 | ||
5450 | /* Calculate original and target relocation values, given local and target | |
5451 | * specs and relocation kind. These values are calculated for each candidate. | |
5452 | * If there are multiple candidates, resulting values should all be consistent | |
5453 | * with each other. Otherwise, libbpf will refuse to proceed due to ambiguity. | |
5454 | * If instruction has to be poisoned, *poison will be set to true. | |
5455 | */ | |
5456 | static int bpf_core_calc_relo(const struct bpf_program *prog, | |
5457 | const struct bpf_core_relo *relo, | |
5458 | int relo_idx, | |
5459 | const struct bpf_core_spec *local_spec, | |
5460 | const struct bpf_core_spec *targ_spec, | |
5461 | struct bpf_core_relo_res *res) | |
5462 | { | |
5463 | int err = -EOPNOTSUPP; | |
5464 | ||
5465 | res->orig_val = 0; | |
5466 | res->new_val = 0; | |
5467 | res->poison = false; | |
5468 | res->validate = true; | |
a66345bc AN |
5469 | res->fail_memsz_adjust = false; |
5470 | res->orig_sz = res->new_sz = 0; | |
5471 | res->orig_type_id = res->new_type_id = 0; | |
353c788c AN |
5472 | |
5473 | if (core_relo_is_field_based(relo->kind)) { | |
a66345bc AN |
5474 | err = bpf_core_calc_field_relo(prog, relo, local_spec, |
5475 | &res->orig_val, &res->orig_sz, | |
5476 | &res->orig_type_id, &res->validate); | |
5477 | err = err ?: bpf_core_calc_field_relo(prog, relo, targ_spec, | |
5478 | &res->new_val, &res->new_sz, | |
5479 | &res->new_type_id, NULL); | |
5480 | if (err) | |
5481 | goto done; | |
5482 | /* Validate if it's safe to adjust load/store memory size. | |
5483 | * Adjustments are performed only if original and new memory | |
5484 | * sizes differ. | |
5485 | */ | |
5486 | res->fail_memsz_adjust = false; | |
5487 | if (res->orig_sz != res->new_sz) { | |
5488 | const struct btf_type *orig_t, *new_t; | |
5489 | ||
5490 | orig_t = btf__type_by_id(local_spec->btf, res->orig_type_id); | |
5491 | new_t = btf__type_by_id(targ_spec->btf, res->new_type_id); | |
5492 | ||
5493 | /* There are two use cases in which it's safe to | |
5494 | * adjust load/store's mem size: | |
5495 | * - reading a 32-bit kernel pointer, while on BPF | |
5496 | * size pointers are always 64-bit; in this case | |
5497 | * it's safe to "downsize" instruction size due to | |
5498 | * pointer being treated as unsigned integer with | |
5499 | * zero-extended upper 32-bits; | |
5500 | * - reading unsigned integers, again due to | |
5501 | * zero-extension is preserving the value correctly. | |
5502 | * | |
5503 | * In all other cases it's incorrect to attempt to | |
5504 | * load/store field because read value will be | |
5505 | * incorrect, so we poison relocated instruction. | |
5506 | */ | |
5507 | if (btf_is_ptr(orig_t) && btf_is_ptr(new_t)) | |
5508 | goto done; | |
5509 | if (btf_is_int(orig_t) && btf_is_int(new_t) && | |
5510 | btf_int_encoding(orig_t) != BTF_INT_SIGNED && | |
5511 | btf_int_encoding(new_t) != BTF_INT_SIGNED) | |
5512 | goto done; | |
5513 | ||
5514 | /* mark as invalid mem size adjustment, but this will | |
5515 | * only be checked for LDX/STX/ST insns | |
5516 | */ | |
5517 | res->fail_memsz_adjust = true; | |
5518 | } | |
3fc32f40 AN |
5519 | } else if (core_relo_is_type_based(relo->kind)) { |
5520 | err = bpf_core_calc_type_relo(relo, local_spec, &res->orig_val); | |
5521 | err = err ?: bpf_core_calc_type_relo(relo, targ_spec, &res->new_val); | |
eacaaed7 AN |
5522 | } else if (core_relo_is_enumval_based(relo->kind)) { |
5523 | err = bpf_core_calc_enumval_relo(relo, local_spec, &res->orig_val); | |
5524 | err = err ?: bpf_core_calc_enumval_relo(relo, targ_spec, &res->new_val); | |
353c788c AN |
5525 | } |
5526 | ||
a66345bc | 5527 | done: |
353c788c AN |
5528 | if (err == -EUCLEAN) { |
5529 | /* EUCLEAN is used to signal instruction poisoning request */ | |
5530 | res->poison = true; | |
5531 | err = 0; | |
5532 | } else if (err == -EOPNOTSUPP) { | |
5533 | /* EOPNOTSUPP means unknown/unsupported relocation */ | |
5534 | pr_warn("prog '%s': relo #%d: unrecognized CO-RE relocation %s (%d) at insn #%d\n", | |
52109584 AN |
5535 | prog->name, relo_idx, core_relo_kind_str(relo->kind), |
5536 | relo->kind, relo->insn_off / 8); | |
353c788c AN |
5537 | } |
5538 | ||
5539 | return err; | |
5540 | } | |
5541 | ||
5542 | /* | |
5543 | * Turn instruction for which CO_RE relocation failed into invalid one with | |
5544 | * distinct signature. | |
5545 | */ | |
5546 | static void bpf_core_poison_insn(struct bpf_program *prog, int relo_idx, | |
5547 | int insn_idx, struct bpf_insn *insn) | |
5548 | { | |
5549 | pr_debug("prog '%s': relo #%d: substituting insn #%d w/ invalid insn\n", | |
52109584 | 5550 | prog->name, relo_idx, insn_idx); |
353c788c AN |
5551 | insn->code = BPF_JMP | BPF_CALL; |
5552 | insn->dst_reg = 0; | |
5553 | insn->src_reg = 0; | |
5554 | insn->off = 0; | |
5555 | /* if this instruction is reachable (not a dead code), | |
5556 | * verifier will complain with the following message: | |
5557 | * invalid func unknown#195896080 | |
5558 | */ | |
5559 | insn->imm = 195896080; /* => 0xbad2310 => "bad relo" */ | |
5560 | } | |
5561 | ||
eacaaed7 AN |
5562 | static bool is_ldimm64(struct bpf_insn *insn) |
5563 | { | |
5564 | return insn->code == (BPF_LD | BPF_IMM | BPF_DW); | |
5565 | } | |
5566 | ||
a66345bc AN |
5567 | static int insn_bpf_size_to_bytes(struct bpf_insn *insn) |
5568 | { | |
5569 | switch (BPF_SIZE(insn->code)) { | |
5570 | case BPF_DW: return 8; | |
5571 | case BPF_W: return 4; | |
5572 | case BPF_H: return 2; | |
5573 | case BPF_B: return 1; | |
5574 | default: return -1; | |
5575 | } | |
5576 | } | |
5577 | ||
5578 | static int insn_bytes_to_bpf_size(__u32 sz) | |
5579 | { | |
5580 | switch (sz) { | |
5581 | case 8: return BPF_DW; | |
5582 | case 4: return BPF_W; | |
5583 | case 2: return BPF_H; | |
5584 | case 1: return BPF_B; | |
5585 | default: return -1; | |
5586 | } | |
5587 | } | |
5588 | ||
ddc7c304 AN |
5589 | /* |
5590 | * Patch relocatable BPF instruction. | |
62561eb4 AN |
5591 | * |
5592 | * Patched value is determined by relocation kind and target specification. | |
353c788c | 5593 | * For existence relocations target spec will be NULL if field/type is not found. |
62561eb4 AN |
5594 | * Expected insn->imm value is determined using relocation kind and local |
5595 | * spec, and is checked before patching instruction. If actual insn->imm value | |
5596 | * is wrong, bail out with error. | |
ddc7c304 | 5597 | * |
a66345bc | 5598 | * Currently supported classes of BPF instruction are: |
ddc7c304 AN |
5599 | * 1. rX = <imm> (assignment with immediate operand); |
5600 | * 2. rX += <imm> (arithmetic operations with immediate operand); | |
a66345bc AN |
5601 | * 3. rX = <imm64> (load with 64-bit immediate value); |
5602 | * 4. rX = *(T *)(rY + <off>), where T is one of {u8, u16, u32, u64}; | |
5603 | * 5. *(T *)(rX + <off>) = rY, where T is one of {u8, u16, u32, u64}; | |
5604 | * 6. *(T *)(rX + <off>) = <imm>, where T is one of {u8, u16, u32, u64}. | |
ddc7c304 | 5605 | */ |
353c788c | 5606 | static int bpf_core_patch_insn(struct bpf_program *prog, |
28b93c64 | 5607 | const struct bpf_core_relo *relo, |
d7a25270 | 5608 | int relo_idx, |
353c788c | 5609 | const struct bpf_core_relo_res *res) |
ddc7c304 | 5610 | { |
62561eb4 | 5611 | __u32 orig_val, new_val; |
ddc7c304 | 5612 | struct bpf_insn *insn; |
353c788c | 5613 | int insn_idx; |
ddc7c304 AN |
5614 | __u8 class; |
5615 | ||
9c0f8cbd | 5616 | if (relo->insn_off % BPF_INSN_SZ) |
62561eb4 | 5617 | return -EINVAL; |
9c0f8cbd | 5618 | insn_idx = relo->insn_off / BPF_INSN_SZ; |
db2b8b06 AN |
5619 | /* adjust insn_idx from section frame of reference to the local |
5620 | * program's frame of reference; (sub-)program code is not yet | |
5621 | * relocated, so it's enough to just subtract in-section offset | |
5622 | */ | |
5623 | insn_idx = insn_idx - prog->sec_insn_off; | |
d7a25270 AN |
5624 | insn = &prog->insns[insn_idx]; |
5625 | class = BPF_CLASS(insn->code); | |
62561eb4 | 5626 | |
353c788c | 5627 | if (res->poison) { |
a66345bc | 5628 | poison: |
eacaaed7 AN |
5629 | /* poison second part of ldimm64 to avoid confusing error from |
5630 | * verifier about "unknown opcode 00" | |
5631 | */ | |
5632 | if (is_ldimm64(insn)) | |
5633 | bpf_core_poison_insn(prog, relo_idx, insn_idx + 1, insn + 1); | |
353c788c | 5634 | bpf_core_poison_insn(prog, relo_idx, insn_idx, insn); |
d7a25270 | 5635 | return 0; |
62561eb4 | 5636 | } |
ddc7c304 | 5637 | |
353c788c AN |
5638 | orig_val = res->orig_val; |
5639 | new_val = res->new_val; | |
5640 | ||
8ab9da57 AN |
5641 | switch (class) { |
5642 | case BPF_ALU: | |
5643 | case BPF_ALU64: | |
ddc7c304 AN |
5644 | if (BPF_SRC(insn->code) != BPF_K) |
5645 | return -EINVAL; | |
353c788c | 5646 | if (res->validate && insn->imm != orig_val) { |
d7a25270 | 5647 | pr_warn("prog '%s': relo #%d: unexpected insn #%d (ALU/ALU64) value: got %u, exp %u -> %u\n", |
52109584 | 5648 | prog->name, relo_idx, |
d7a25270 | 5649 | insn_idx, insn->imm, orig_val, new_val); |
ddc7c304 | 5650 | return -EINVAL; |
ee26dade AN |
5651 | } |
5652 | orig_val = insn->imm; | |
62561eb4 | 5653 | insn->imm = new_val; |
d7a25270 | 5654 | pr_debug("prog '%s': relo #%d: patched insn #%d (ALU/ALU64) imm %u -> %u\n", |
52109584 | 5655 | prog->name, relo_idx, insn_idx, |
d7a25270 | 5656 | orig_val, new_val); |
8ab9da57 AN |
5657 | break; |
5658 | case BPF_LDX: | |
5659 | case BPF_ST: | |
5660 | case BPF_STX: | |
353c788c | 5661 | if (res->validate && insn->off != orig_val) { |
eacaaed7 | 5662 | pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDX/ST/STX) value: got %u, exp %u -> %u\n", |
52109584 | 5663 | prog->name, relo_idx, insn_idx, insn->off, orig_val, new_val); |
8ab9da57 AN |
5664 | return -EINVAL; |
5665 | } | |
5666 | if (new_val > SHRT_MAX) { | |
d7a25270 | 5667 | pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) value too big: %u\n", |
52109584 | 5668 | prog->name, relo_idx, insn_idx, new_val); |
8ab9da57 AN |
5669 | return -ERANGE; |
5670 | } | |
a66345bc AN |
5671 | if (res->fail_memsz_adjust) { |
5672 | pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) accesses field incorrectly. " | |
5673 | "Make sure you are accessing pointers, unsigned integers, or fields of matching type and size.\n", | |
5674 | prog->name, relo_idx, insn_idx); | |
5675 | goto poison; | |
5676 | } | |
5677 | ||
8ab9da57 AN |
5678 | orig_val = insn->off; |
5679 | insn->off = new_val; | |
d7a25270 | 5680 | pr_debug("prog '%s': relo #%d: patched insn #%d (LDX/ST/STX) off %u -> %u\n", |
52109584 | 5681 | prog->name, relo_idx, insn_idx, orig_val, new_val); |
a66345bc AN |
5682 | |
5683 | if (res->new_sz != res->orig_sz) { | |
5684 | int insn_bytes_sz, insn_bpf_sz; | |
5685 | ||
5686 | insn_bytes_sz = insn_bpf_size_to_bytes(insn); | |
5687 | if (insn_bytes_sz != res->orig_sz) { | |
5688 | pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) unexpected mem size: got %d, exp %u\n", | |
5689 | prog->name, relo_idx, insn_idx, insn_bytes_sz, res->orig_sz); | |
5690 | return -EINVAL; | |
5691 | } | |
5692 | ||
5693 | insn_bpf_sz = insn_bytes_to_bpf_size(res->new_sz); | |
5694 | if (insn_bpf_sz < 0) { | |
5695 | pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) invalid new mem size: %u\n", | |
5696 | prog->name, relo_idx, insn_idx, res->new_sz); | |
5697 | return -EINVAL; | |
5698 | } | |
5699 | ||
5700 | insn->code = BPF_MODE(insn->code) | insn_bpf_sz | BPF_CLASS(insn->code); | |
5701 | pr_debug("prog '%s': relo #%d: patched insn #%d (LDX/ST/STX) mem_sz %u -> %u\n", | |
5702 | prog->name, relo_idx, insn_idx, res->orig_sz, res->new_sz); | |
5703 | } | |
8ab9da57 | 5704 | break; |
eacaaed7 AN |
5705 | case BPF_LD: { |
5706 | __u64 imm; | |
5707 | ||
5708 | if (!is_ldimm64(insn) || | |
5709 | insn[0].src_reg != 0 || insn[0].off != 0 || | |
5710 | insn_idx + 1 >= prog->insns_cnt || | |
5711 | insn[1].code != 0 || insn[1].dst_reg != 0 || | |
5712 | insn[1].src_reg != 0 || insn[1].off != 0) { | |
5713 | pr_warn("prog '%s': relo #%d: insn #%d (LDIMM64) has unexpected form\n", | |
52109584 | 5714 | prog->name, relo_idx, insn_idx); |
eacaaed7 AN |
5715 | return -EINVAL; |
5716 | } | |
5717 | ||
5718 | imm = insn[0].imm + ((__u64)insn[1].imm << 32); | |
5719 | if (res->validate && imm != orig_val) { | |
5720 | pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDIMM64) value: got %llu, exp %u -> %u\n", | |
52109584 | 5721 | prog->name, relo_idx, |
2e80be60 AN |
5722 | insn_idx, (unsigned long long)imm, |
5723 | orig_val, new_val); | |
eacaaed7 AN |
5724 | return -EINVAL; |
5725 | } | |
5726 | ||
5727 | insn[0].imm = new_val; | |
5728 | insn[1].imm = 0; /* currently only 32-bit values are supported */ | |
5729 | pr_debug("prog '%s': relo #%d: patched insn #%d (LDIMM64) imm64 %llu -> %u\n", | |
52109584 | 5730 | prog->name, relo_idx, insn_idx, |
2e80be60 | 5731 | (unsigned long long)imm, new_val); |
eacaaed7 AN |
5732 | break; |
5733 | } | |
8ab9da57 | 5734 | default: |
eacaaed7 | 5735 | pr_warn("prog '%s': relo #%d: trying to relocate unrecognized insn #%d, code:0x%x, src:0x%x, dst:0x%x, off:0x%x, imm:0x%x\n", |
52109584 AN |
5736 | prog->name, relo_idx, insn_idx, insn->code, |
5737 | insn->src_reg, insn->dst_reg, insn->off, insn->imm); | |
ddc7c304 AN |
5738 | return -EINVAL; |
5739 | } | |
62561eb4 | 5740 | |
ddc7c304 AN |
5741 | return 0; |
5742 | } | |
5743 | ||
ddc7c304 AN |
5744 | /* Output spec definition in the format: |
5745 | * [<type-id>] (<type-name>) + <raw-spec> => <offset>@<spec>, | |
5746 | * where <spec> is a C-syntax view of recorded field access, e.g.: x.a[3].b | |
5747 | */ | |
5748 | static void bpf_core_dump_spec(int level, const struct bpf_core_spec *spec) | |
5749 | { | |
5750 | const struct btf_type *t; | |
eacaaed7 | 5751 | const struct btf_enum *e; |
ddc7c304 AN |
5752 | const char *s; |
5753 | __u32 type_id; | |
5754 | int i; | |
5755 | ||
28b93c64 | 5756 | type_id = spec->root_type_id; |
ddc7c304 AN |
5757 | t = btf__type_by_id(spec->btf, type_id); |
5758 | s = btf__name_by_offset(spec->btf, t->name_off); | |
ddc7c304 | 5759 | |
28b93c64 AN |
5760 | libbpf_print(level, "[%u] %s %s", type_id, btf_kind_str(t), str_is_empty(s) ? "<anon>" : s); |
5761 | ||
3fc32f40 AN |
5762 | if (core_relo_is_type_based(spec->relo_kind)) |
5763 | return; | |
5764 | ||
eacaaed7 AN |
5765 | if (core_relo_is_enumval_based(spec->relo_kind)) { |
5766 | t = skip_mods_and_typedefs(spec->btf, type_id, NULL); | |
5767 | e = btf_enum(t) + spec->raw_spec[0]; | |
5768 | s = btf__name_by_offset(spec->btf, e->name_off); | |
5769 | ||
5770 | libbpf_print(level, "::%s = %u", s, e->val); | |
5771 | return; | |
5772 | } | |
5773 | ||
28b93c64 AN |
5774 | if (core_relo_is_field_based(spec->relo_kind)) { |
5775 | for (i = 0; i < spec->len; i++) { | |
5776 | if (spec->spec[i].name) | |
5777 | libbpf_print(level, ".%s", spec->spec[i].name); | |
5778 | else if (i > 0 || spec->spec[i].idx > 0) | |
5779 | libbpf_print(level, "[%u]", spec->spec[i].idx); | |
5780 | } | |
ddc7c304 | 5781 | |
28b93c64 AN |
5782 | libbpf_print(level, " ("); |
5783 | for (i = 0; i < spec->raw_len; i++) | |
5784 | libbpf_print(level, "%s%d", i == 0 ? "" : ":", spec->raw_spec[i]); | |
ddc7c304 | 5785 | |
28b93c64 AN |
5786 | if (spec->bit_offset % 8) |
5787 | libbpf_print(level, " @ offset %u.%u)", | |
5788 | spec->bit_offset / 8, spec->bit_offset % 8); | |
ddc7c304 | 5789 | else |
28b93c64 | 5790 | libbpf_print(level, " @ offset %u)", spec->bit_offset / 8); |
3fc32f40 | 5791 | return; |
ddc7c304 | 5792 | } |
ddc7c304 AN |
5793 | } |
5794 | ||
5795 | static size_t bpf_core_hash_fn(const void *key, void *ctx) | |
5796 | { | |
5797 | return (size_t)key; | |
5798 | } | |
5799 | ||
5800 | static bool bpf_core_equal_fn(const void *k1, const void *k2, void *ctx) | |
5801 | { | |
5802 | return k1 == k2; | |
5803 | } | |
5804 | ||
5805 | static void *u32_as_hash_key(__u32 x) | |
5806 | { | |
5807 | return (void *)(uintptr_t)x; | |
5808 | } | |
5809 | ||
5810 | /* | |
5811 | * CO-RE relocate single instruction. | |
5812 | * | |
5813 | * The outline and important points of the algorithm: | |
5814 | * 1. For given local type, find corresponding candidate target types. | |
5815 | * Candidate type is a type with the same "essential" name, ignoring | |
5816 | * everything after last triple underscore (___). E.g., `sample`, | |
5817 | * `sample___flavor_one`, `sample___flavor_another_one`, are all candidates | |
5818 | * for each other. Names with triple underscore are referred to as | |
5819 | * "flavors" and are useful, among other things, to allow to | |
5820 | * specify/support incompatible variations of the same kernel struct, which | |
5821 | * might differ between different kernel versions and/or build | |
5822 | * configurations. | |
5823 | * | |
5824 | * N.B. Struct "flavors" could be generated by bpftool's BTF-to-C | |
5825 | * converter, when deduplicated BTF of a kernel still contains more than | |
5826 | * one different types with the same name. In that case, ___2, ___3, etc | |
5827 | * are appended starting from second name conflict. But start flavors are | |
5828 | * also useful to be defined "locally", in BPF program, to extract same | |
5829 | * data from incompatible changes between different kernel | |
5830 | * versions/configurations. For instance, to handle field renames between | |
5831 | * kernel versions, one can use two flavors of the struct name with the | |
5832 | * same common name and use conditional relocations to extract that field, | |
5833 | * depending on target kernel version. | |
5834 | * 2. For each candidate type, try to match local specification to this | |
5835 | * candidate target type. Matching involves finding corresponding | |
5836 | * high-level spec accessors, meaning that all named fields should match, | |
5837 | * as well as all array accesses should be within the actual bounds. Also, | |
5838 | * types should be compatible (see bpf_core_fields_are_compat for details). | |
5839 | * 3. It is supported and expected that there might be multiple flavors | |
5840 | * matching the spec. As long as all the specs resolve to the same set of | |
511bb008 | 5841 | * offsets across all candidates, there is no error. If there is any |
ddc7c304 AN |
5842 | * ambiguity, CO-RE relocation will fail. This is necessary to accomodate |
5843 | * imprefection of BTF deduplication, which can cause slight duplication of | |
5844 | * the same BTF type, if some directly or indirectly referenced (by | |
5845 | * pointer) type gets resolved to different actual types in different | |
5846 | * object files. If such situation occurs, deduplicated BTF will end up | |
5847 | * with two (or more) structurally identical types, which differ only in | |
5848 | * types they refer to through pointer. This should be OK in most cases and | |
5849 | * is not an error. | |
5850 | * 4. Candidate types search is performed by linearly scanning through all | |
5851 | * types in target BTF. It is anticipated that this is overall more | |
5852 | * efficient memory-wise and not significantly worse (if not better) | |
5853 | * CPU-wise compared to prebuilding a map from all local type names to | |
5854 | * a list of candidate type names. It's also sped up by caching resolved | |
5855 | * list of matching candidates per each local "root" type ID, that has at | |
28b93c64 | 5856 | * least one bpf_core_relo associated with it. This list is shared |
ddc7c304 AN |
5857 | * between multiple relocations for the same type ID and is updated as some |
5858 | * of the candidates are pruned due to structural incompatibility. | |
5859 | */ | |
3fc32f40 AN |
5860 | static int bpf_core_apply_relo(struct bpf_program *prog, |
5861 | const struct bpf_core_relo *relo, | |
5862 | int relo_idx, | |
5863 | const struct btf *local_btf, | |
3fc32f40 | 5864 | struct hashmap *cand_cache) |
ddc7c304 | 5865 | { |
3418c56d | 5866 | struct bpf_core_spec local_spec, cand_spec, targ_spec = {}; |
ddc7c304 | 5867 | const void *type_key = u32_as_hash_key(relo->type_id); |
353c788c | 5868 | struct bpf_core_relo_res cand_res, targ_res; |
28b93c64 AN |
5869 | const struct btf_type *local_type; |
5870 | const char *local_name; | |
0f7515ca AN |
5871 | struct core_cand_list *cands = NULL; |
5872 | __u32 local_id; | |
ddc7c304 AN |
5873 | const char *spec_str; |
5874 | int i, j, err; | |
5875 | ||
5876 | local_id = relo->type_id; | |
5877 | local_type = btf__type_by_id(local_btf, local_id); | |
5878 | if (!local_type) | |
5879 | return -EINVAL; | |
5880 | ||
5881 | local_name = btf__name_by_offset(local_btf, local_type->name_off); | |
3fc32f40 | 5882 | if (!local_name) |
ddc7c304 AN |
5883 | return -EINVAL; |
5884 | ||
5885 | spec_str = btf__name_by_offset(local_btf, relo->access_str_off); | |
5886 | if (str_is_empty(spec_str)) | |
5887 | return -EINVAL; | |
5888 | ||
28b93c64 | 5889 | err = bpf_core_parse_spec(local_btf, local_id, spec_str, relo->kind, &local_spec); |
ddc7c304 | 5890 | if (err) { |
28b93c64 | 5891 | pr_warn("prog '%s': relo #%d: parsing [%d] %s %s + %s failed: %d\n", |
52109584 | 5892 | prog->name, relo_idx, local_id, btf_kind_str(local_type), |
3fc32f40 AN |
5893 | str_is_empty(local_name) ? "<anon>" : local_name, |
5894 | spec_str, err); | |
ddc7c304 AN |
5895 | return -EINVAL; |
5896 | } | |
5897 | ||
52109584 | 5898 | pr_debug("prog '%s': relo #%d: kind <%s> (%d), spec is ", prog->name, |
28b93c64 | 5899 | relo_idx, core_relo_kind_str(relo->kind), relo->kind); |
ddc7c304 AN |
5900 | bpf_core_dump_spec(LIBBPF_DEBUG, &local_spec); |
5901 | libbpf_print(LIBBPF_DEBUG, "\n"); | |
5902 | ||
3fc32f40 AN |
5903 | /* TYPE_ID_LOCAL relo is special and doesn't need candidate search */ |
5904 | if (relo->kind == BPF_TYPE_ID_LOCAL) { | |
5905 | targ_res.validate = true; | |
5906 | targ_res.poison = false; | |
5907 | targ_res.orig_val = local_spec.root_type_id; | |
5908 | targ_res.new_val = local_spec.root_type_id; | |
5909 | goto patch_insn; | |
5910 | } | |
5911 | ||
5912 | /* libbpf doesn't support candidate search for anonymous types */ | |
5913 | if (str_is_empty(spec_str)) { | |
5914 | pr_warn("prog '%s': relo #%d: <%s> (%d) relocation doesn't support anonymous types\n", | |
52109584 | 5915 | prog->name, relo_idx, core_relo_kind_str(relo->kind), relo->kind); |
3fc32f40 AN |
5916 | return -EOPNOTSUPP; |
5917 | } | |
5918 | ||
0f7515ca AN |
5919 | if (!hashmap__find(cand_cache, type_key, (void **)&cands)) { |
5920 | cands = bpf_core_find_cands(prog->obj, local_btf, local_id); | |
5921 | if (IS_ERR(cands)) { | |
4f33a53d | 5922 | pr_warn("prog '%s': relo #%d: target candidate search failed for [%d] %s %s: %ld\n", |
52109584 | 5923 | prog->name, relo_idx, local_id, btf_kind_str(local_type), |
0f7515ca AN |
5924 | local_name, PTR_ERR(cands)); |
5925 | return PTR_ERR(cands); | |
ddc7c304 | 5926 | } |
0f7515ca | 5927 | err = hashmap__set(cand_cache, type_key, cands, NULL, NULL); |
ddc7c304 | 5928 | if (err) { |
0f7515ca | 5929 | bpf_core_free_cands(cands); |
ddc7c304 AN |
5930 | return err; |
5931 | } | |
5932 | } | |
5933 | ||
0f7515ca AN |
5934 | for (i = 0, j = 0; i < cands->len; i++) { |
5935 | err = bpf_core_spec_match(&local_spec, cands->cands[i].btf, | |
5936 | cands->cands[i].id, &cand_spec); | |
ddc7c304 | 5937 | if (err < 0) { |
28b93c64 | 5938 | pr_warn("prog '%s': relo #%d: error matching candidate #%d ", |
52109584 | 5939 | prog->name, relo_idx, i); |
28b93c64 AN |
5940 | bpf_core_dump_spec(LIBBPF_WARN, &cand_spec); |
5941 | libbpf_print(LIBBPF_WARN, ": %d\n", err); | |
ddc7c304 AN |
5942 | return err; |
5943 | } | |
28b93c64 | 5944 | |
52109584 | 5945 | pr_debug("prog '%s': relo #%d: %s candidate #%d ", prog->name, |
28b93c64 AN |
5946 | relo_idx, err == 0 ? "non-matching" : "matching", i); |
5947 | bpf_core_dump_spec(LIBBPF_DEBUG, &cand_spec); | |
5948 | libbpf_print(LIBBPF_DEBUG, "\n"); | |
5949 | ||
ddc7c304 AN |
5950 | if (err == 0) |
5951 | continue; | |
5952 | ||
353c788c AN |
5953 | err = bpf_core_calc_relo(prog, relo, relo_idx, &local_spec, &cand_spec, &cand_res); |
5954 | if (err) | |
5955 | return err; | |
5956 | ||
ddc7c304 | 5957 | if (j == 0) { |
353c788c | 5958 | targ_res = cand_res; |
ddc7c304 | 5959 | targ_spec = cand_spec; |
ee26dade | 5960 | } else if (cand_spec.bit_offset != targ_spec.bit_offset) { |
353c788c AN |
5961 | /* if there are many field relo candidates, they |
5962 | * should all resolve to the same bit offset | |
ddc7c304 | 5963 | */ |
353c788c | 5964 | pr_warn("prog '%s': relo #%d: field offset ambiguity: %u != %u\n", |
52109584 | 5965 | prog->name, relo_idx, cand_spec.bit_offset, |
ee26dade | 5966 | targ_spec.bit_offset); |
ddc7c304 | 5967 | return -EINVAL; |
353c788c AN |
5968 | } else if (cand_res.poison != targ_res.poison || cand_res.new_val != targ_res.new_val) { |
5969 | /* all candidates should result in the same relocation | |
5970 | * decision and value, otherwise it's dangerous to | |
5971 | * proceed due to ambiguity | |
5972 | */ | |
5973 | pr_warn("prog '%s': relo #%d: relocation decision ambiguity: %s %u != %s %u\n", | |
52109584 | 5974 | prog->name, relo_idx, |
353c788c AN |
5975 | cand_res.poison ? "failure" : "success", cand_res.new_val, |
5976 | targ_res.poison ? "failure" : "success", targ_res.new_val); | |
5977 | return -EINVAL; | |
ddc7c304 AN |
5978 | } |
5979 | ||
0f7515ca | 5980 | cands->cands[j++] = cands->cands[i]; |
ddc7c304 AN |
5981 | } |
5982 | ||
62561eb4 | 5983 | /* |
d7a25270 AN |
5984 | * For BPF_FIELD_EXISTS relo or when used BPF program has field |
5985 | * existence checks or kernel version/config checks, it's expected | |
5986 | * that we might not find any candidates. In this case, if field | |
5987 | * wasn't found in any candidate, the list of candidates shouldn't | |
5988 | * change at all, we'll just handle relocating appropriately, | |
5989 | * depending on relo's kind. | |
62561eb4 AN |
5990 | */ |
5991 | if (j > 0) | |
0f7515ca | 5992 | cands->len = j; |
62561eb4 | 5993 | |
d7a25270 AN |
5994 | /* |
5995 | * If no candidates were found, it might be both a programmer error, | |
5996 | * as well as expected case, depending whether instruction w/ | |
5997 | * relocation is guarded in some way that makes it unreachable (dead | |
5998 | * code) if relocation can't be resolved. This is handled in | |
3fc32f40 | 5999 | * bpf_core_patch_insn() uniformly by replacing that instruction with |
d7a25270 AN |
6000 | * BPF helper call insn (using invalid helper ID). If that instruction |
6001 | * is indeed unreachable, then it will be ignored and eliminated by | |
6002 | * verifier. If it was an error, then verifier will complain and point | |
6003 | * to a specific instruction number in its log. | |
6004 | */ | |
353c788c | 6005 | if (j == 0) { |
28b93c64 | 6006 | pr_debug("prog '%s': relo #%d: no matching targets found\n", |
52109584 | 6007 | prog->name, relo_idx); |
ddc7c304 | 6008 | |
353c788c AN |
6009 | /* calculate single target relo result explicitly */ |
6010 | err = bpf_core_calc_relo(prog, relo, relo_idx, &local_spec, NULL, &targ_res); | |
6011 | if (err) | |
6012 | return err; | |
6013 | } | |
6014 | ||
3fc32f40 | 6015 | patch_insn: |
353c788c AN |
6016 | /* bpf_core_patch_insn() should know how to handle missing targ_spec */ |
6017 | err = bpf_core_patch_insn(prog, relo, relo_idx, &targ_res); | |
ddc7c304 | 6018 | if (err) { |
be18010e | 6019 | pr_warn("prog '%s': relo #%d: failed to patch insn at offset %d: %d\n", |
52109584 | 6020 | prog->name, relo_idx, relo->insn_off, err); |
ddc7c304 AN |
6021 | return -EINVAL; |
6022 | } | |
6023 | ||
6024 | return 0; | |
6025 | } | |
6026 | ||
6027 | static int | |
28b93c64 | 6028 | bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path) |
ddc7c304 AN |
6029 | { |
6030 | const struct btf_ext_info_sec *sec; | |
28b93c64 | 6031 | const struct bpf_core_relo *rec; |
ddc7c304 AN |
6032 | const struct btf_ext_info *seg; |
6033 | struct hashmap_entry *entry; | |
6034 | struct hashmap *cand_cache = NULL; | |
6035 | struct bpf_program *prog; | |
ddc7c304 | 6036 | const char *sec_name; |
db2b8b06 | 6037 | int i, err = 0, insn_idx, sec_idx; |
ddc7c304 | 6038 | |
28b93c64 AN |
6039 | if (obj->btf_ext->core_relo_info.len == 0) |
6040 | return 0; | |
6041 | ||
0f7515ca AN |
6042 | if (targ_btf_path) { |
6043 | obj->btf_vmlinux_override = btf__parse(targ_btf_path, NULL); | |
6044 | if (IS_ERR_OR_NULL(obj->btf_vmlinux_override)) { | |
6045 | err = PTR_ERR(obj->btf_vmlinux_override); | |
6046 | pr_warn("failed to parse target BTF: %d\n", err); | |
6047 | return err; | |
6048 | } | |
ddc7c304 AN |
6049 | } |
6050 | ||
6051 | cand_cache = hashmap__new(bpf_core_hash_fn, bpf_core_equal_fn, NULL); | |
6052 | if (IS_ERR(cand_cache)) { | |
6053 | err = PTR_ERR(cand_cache); | |
6054 | goto out; | |
6055 | } | |
6056 | ||
28b93c64 | 6057 | seg = &obj->btf_ext->core_relo_info; |
ddc7c304 AN |
6058 | for_each_btf_ext_sec(seg, sec) { |
6059 | sec_name = btf__name_by_offset(obj->btf, sec->sec_name_off); | |
6060 | if (str_is_empty(sec_name)) { | |
6061 | err = -EINVAL; | |
6062 | goto out; | |
6063 | } | |
db2b8b06 AN |
6064 | /* bpf_object's ELF is gone by now so it's not easy to find |
6065 | * section index by section name, but we can find *any* | |
6066 | * bpf_program within desired section name and use it's | |
6067 | * prog->sec_idx to do a proper search by section index and | |
6068 | * instruction offset | |
6069 | */ | |
9c82a63c AN |
6070 | prog = NULL; |
6071 | for (i = 0; i < obj->nr_programs; i++) { | |
db2b8b06 | 6072 | prog = &obj->programs[i]; |
52109584 | 6073 | if (strcmp(prog->sec_name, sec_name) == 0) |
9c82a63c | 6074 | break; |
9c82a63c | 6075 | } |
ddc7c304 | 6076 | if (!prog) { |
db2b8b06 AN |
6077 | pr_warn("sec '%s': failed to find a BPF program\n", sec_name); |
6078 | return -ENOENT; | |
ddc7c304 | 6079 | } |
db2b8b06 | 6080 | sec_idx = prog->sec_idx; |
ddc7c304 | 6081 | |
9c0f8cbd | 6082 | pr_debug("sec '%s': found %d CO-RE relocations\n", |
ddc7c304 AN |
6083 | sec_name, sec->num_info); |
6084 | ||
6085 | for_each_btf_ext_rec(seg, sec, i, rec) { | |
db2b8b06 AN |
6086 | insn_idx = rec->insn_off / BPF_INSN_SZ; |
6087 | prog = find_prog_by_sec_insn(obj, sec_idx, insn_idx); | |
6088 | if (!prog) { | |
6089 | pr_warn("sec '%s': failed to find program at insn #%d for CO-RE offset relocation #%d\n", | |
6090 | sec_name, insn_idx, i); | |
6091 | err = -EINVAL; | |
6092 | goto out; | |
6093 | } | |
47f7cf63 AN |
6094 | /* no need to apply CO-RE relocation if the program is |
6095 | * not going to be loaded | |
6096 | */ | |
6097 | if (!prog->load) | |
6098 | continue; | |
db2b8b06 | 6099 | |
0f7515ca | 6100 | err = bpf_core_apply_relo(prog, rec, i, obj->btf, cand_cache); |
ddc7c304 | 6101 | if (err) { |
be18010e | 6102 | pr_warn("prog '%s': relo #%d: failed to relocate: %d\n", |
9c0f8cbd | 6103 | prog->name, i, err); |
ddc7c304 AN |
6104 | goto out; |
6105 | } | |
6106 | } | |
6107 | } | |
6108 | ||
6109 | out: | |
4f33a53d | 6110 | /* obj->btf_vmlinux and module BTFs are freed after object load */ |
0f7515ca AN |
6111 | btf__free(obj->btf_vmlinux_override); |
6112 | obj->btf_vmlinux_override = NULL; | |
6113 | ||
ddc7c304 AN |
6114 | if (!IS_ERR_OR_NULL(cand_cache)) { |
6115 | hashmap__for_each_entry(cand_cache, entry, i) { | |
6116 | bpf_core_free_cands(entry->value); | |
6117 | } | |
6118 | hashmap__free(cand_cache); | |
6119 | } | |
6120 | return err; | |
6121 | } | |
6122 | ||
c3c55696 AN |
6123 | /* Relocate data references within program code: |
6124 | * - map references; | |
6125 | * - global variable references; | |
6126 | * - extern references. | |
6127 | */ | |
48cca7e4 | 6128 | static int |
c3c55696 | 6129 | bpf_object__relocate_data(struct bpf_object *obj, struct bpf_program *prog) |
8a47a6c5 | 6130 | { |
c3c55696 | 6131 | int i; |
8a47a6c5 WN |
6132 | |
6133 | for (i = 0; i < prog->nr_reloc; i++) { | |
53f8dd43 | 6134 | struct reloc_desc *relo = &prog->reloc_desc[i]; |
166750bc | 6135 | struct bpf_insn *insn = &prog->insns[relo->insn_idx]; |
2e33efe3 | 6136 | struct extern_desc *ext; |
8a47a6c5 | 6137 | |
166750bc AN |
6138 | switch (relo->type) { |
6139 | case RELO_LD64: | |
6140 | insn[0].src_reg = BPF_PSEUDO_MAP_FD; | |
6141 | insn[0].imm = obj->maps[relo->map_idx].fd; | |
c3c55696 | 6142 | relo->processed = true; |
166750bc AN |
6143 | break; |
6144 | case RELO_DATA: | |
6145 | insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; | |
6146 | insn[1].imm = insn[0].imm + relo->sym_off; | |
53f8dd43 | 6147 | insn[0].imm = obj->maps[relo->map_idx].fd; |
c3c55696 | 6148 | relo->processed = true; |
166750bc AN |
6149 | break; |
6150 | case RELO_EXTERN: | |
2e33efe3 | 6151 | ext = &obj->externs[relo->sym_off]; |
1c0c7074 AN |
6152 | if (ext->type == EXT_KCFG) { |
6153 | insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; | |
6154 | insn[0].imm = obj->maps[obj->kconfig_map_idx].fd; | |
6155 | insn[1].imm = ext->kcfg.data_off; | |
6156 | } else /* EXT_KSYM */ { | |
d370bbe1 HL |
6157 | if (ext->ksym.type_id) { /* typed ksyms */ |
6158 | insn[0].src_reg = BPF_PSEUDO_BTF_ID; | |
6159 | insn[0].imm = ext->ksym.vmlinux_btf_id; | |
6160 | } else { /* typeless ksyms */ | |
6161 | insn[0].imm = (__u32)ext->ksym.addr; | |
6162 | insn[1].imm = ext->ksym.addr >> 32; | |
6163 | } | |
1c0c7074 | 6164 | } |
c3c55696 | 6165 | relo->processed = true; |
166750bc AN |
6166 | break; |
6167 | case RELO_CALL: | |
c3c55696 | 6168 | /* will be handled as a follow up pass */ |
166750bc AN |
6169 | break; |
6170 | default: | |
9c0f8cbd AN |
6171 | pr_warn("prog '%s': relo #%d: bad relo type %d\n", |
6172 | prog->name, i, relo->type); | |
166750bc | 6173 | return -EINVAL; |
8a47a6c5 | 6174 | } |
8a47a6c5 WN |
6175 | } |
6176 | ||
c3c55696 AN |
6177 | return 0; |
6178 | } | |
6179 | ||
8505e870 AN |
6180 | static int adjust_prog_btf_ext_info(const struct bpf_object *obj, |
6181 | const struct bpf_program *prog, | |
6182 | const struct btf_ext_info *ext_info, | |
6183 | void **prog_info, __u32 *prog_rec_cnt, | |
6184 | __u32 *prog_rec_sz) | |
6185 | { | |
6186 | void *copy_start = NULL, *copy_end = NULL; | |
6187 | void *rec, *rec_end, *new_prog_info; | |
6188 | const struct btf_ext_info_sec *sec; | |
6189 | size_t old_sz, new_sz; | |
6190 | const char *sec_name; | |
6191 | int i, off_adj; | |
6192 | ||
6193 | for_each_btf_ext_sec(ext_info, sec) { | |
6194 | sec_name = btf__name_by_offset(obj->btf, sec->sec_name_off); | |
6195 | if (!sec_name) | |
6196 | return -EINVAL; | |
52109584 | 6197 | if (strcmp(sec_name, prog->sec_name) != 0) |
8505e870 AN |
6198 | continue; |
6199 | ||
6200 | for_each_btf_ext_rec(ext_info, sec, i, rec) { | |
6201 | __u32 insn_off = *(__u32 *)rec / BPF_INSN_SZ; | |
6202 | ||
6203 | if (insn_off < prog->sec_insn_off) | |
6204 | continue; | |
6205 | if (insn_off >= prog->sec_insn_off + prog->sec_insn_cnt) | |
6206 | break; | |
6207 | ||
6208 | if (!copy_start) | |
6209 | copy_start = rec; | |
6210 | copy_end = rec + ext_info->rec_size; | |
6211 | } | |
6212 | ||
6213 | if (!copy_start) | |
6214 | return -ENOENT; | |
6215 | ||
6216 | /* append func/line info of a given (sub-)program to the main | |
6217 | * program func/line info | |
6218 | */ | |
8eb62958 | 6219 | old_sz = (size_t)(*prog_rec_cnt) * ext_info->rec_size; |
8505e870 AN |
6220 | new_sz = old_sz + (copy_end - copy_start); |
6221 | new_prog_info = realloc(*prog_info, new_sz); | |
6222 | if (!new_prog_info) | |
6223 | return -ENOMEM; | |
6224 | *prog_info = new_prog_info; | |
6225 | *prog_rec_cnt = new_sz / ext_info->rec_size; | |
6226 | memcpy(new_prog_info + old_sz, copy_start, copy_end - copy_start); | |
6227 | ||
6228 | /* Kernel instruction offsets are in units of 8-byte | |
6229 | * instructions, while .BTF.ext instruction offsets generated | |
6230 | * by Clang are in units of bytes. So convert Clang offsets | |
6231 | * into kernel offsets and adjust offset according to program | |
6232 | * relocated position. | |
6233 | */ | |
6234 | off_adj = prog->sub_insn_off - prog->sec_insn_off; | |
6235 | rec = new_prog_info + old_sz; | |
6236 | rec_end = new_prog_info + new_sz; | |
6237 | for (; rec < rec_end; rec += ext_info->rec_size) { | |
6238 | __u32 *insn_off = rec; | |
6239 | ||
6240 | *insn_off = *insn_off / BPF_INSN_SZ + off_adj; | |
6241 | } | |
6242 | *prog_rec_sz = ext_info->rec_size; | |
6243 | return 0; | |
6244 | } | |
6245 | ||
6246 | return -ENOENT; | |
6247 | } | |
6248 | ||
6249 | static int | |
6250 | reloc_prog_func_and_line_info(const struct bpf_object *obj, | |
6251 | struct bpf_program *main_prog, | |
6252 | const struct bpf_program *prog) | |
6253 | { | |
6254 | int err; | |
6255 | ||
6256 | /* no .BTF.ext relocation if .BTF.ext is missing or kernel doesn't | |
6257 | * supprot func/line info | |
6258 | */ | |
6259 | if (!obj->btf_ext || !kernel_supports(FEAT_BTF_FUNC)) | |
6260 | return 0; | |
6261 | ||
6262 | /* only attempt func info relocation if main program's func_info | |
6263 | * relocation was successful | |
6264 | */ | |
6265 | if (main_prog != prog && !main_prog->func_info) | |
6266 | goto line_info; | |
6267 | ||
6268 | err = adjust_prog_btf_ext_info(obj, prog, &obj->btf_ext->func_info, | |
6269 | &main_prog->func_info, | |
6270 | &main_prog->func_info_cnt, | |
6271 | &main_prog->func_info_rec_size); | |
6272 | if (err) { | |
6273 | if (err != -ENOENT) { | |
6274 | pr_warn("prog '%s': error relocating .BTF.ext function info: %d\n", | |
6275 | prog->name, err); | |
6276 | return err; | |
6277 | } | |
6278 | if (main_prog->func_info) { | |
6279 | /* | |
6280 | * Some info has already been found but has problem | |
6281 | * in the last btf_ext reloc. Must have to error out. | |
6282 | */ | |
6283 | pr_warn("prog '%s': missing .BTF.ext function info.\n", prog->name); | |
6284 | return err; | |
6285 | } | |
6286 | /* Have problem loading the very first info. Ignore the rest. */ | |
6287 | pr_warn("prog '%s': missing .BTF.ext function info for the main program, skipping all of .BTF.ext func info.\n", | |
6288 | prog->name); | |
6289 | } | |
6290 | ||
6291 | line_info: | |
6292 | /* don't relocate line info if main program's relocation failed */ | |
6293 | if (main_prog != prog && !main_prog->line_info) | |
6294 | return 0; | |
6295 | ||
6296 | err = adjust_prog_btf_ext_info(obj, prog, &obj->btf_ext->line_info, | |
6297 | &main_prog->line_info, | |
6298 | &main_prog->line_info_cnt, | |
6299 | &main_prog->line_info_rec_size); | |
6300 | if (err) { | |
6301 | if (err != -ENOENT) { | |
6302 | pr_warn("prog '%s': error relocating .BTF.ext line info: %d\n", | |
6303 | prog->name, err); | |
6304 | return err; | |
6305 | } | |
6306 | if (main_prog->line_info) { | |
6307 | /* | |
6308 | * Some info has already been found but has problem | |
6309 | * in the last btf_ext reloc. Must have to error out. | |
6310 | */ | |
6311 | pr_warn("prog '%s': missing .BTF.ext line info.\n", prog->name); | |
6312 | return err; | |
6313 | } | |
6314 | /* Have problem loading the very first info. Ignore the rest. */ | |
6315 | pr_warn("prog '%s': missing .BTF.ext line info for the main program, skipping all of .BTF.ext line info.\n", | |
6316 | prog->name); | |
6317 | } | |
6318 | return 0; | |
6319 | } | |
6320 | ||
c3c55696 AN |
6321 | static int cmp_relo_by_insn_idx(const void *key, const void *elem) |
6322 | { | |
6323 | size_t insn_idx = *(const size_t *)key; | |
6324 | const struct reloc_desc *relo = elem; | |
6325 | ||
6326 | if (insn_idx == relo->insn_idx) | |
6327 | return 0; | |
6328 | return insn_idx < relo->insn_idx ? -1 : 1; | |
6329 | } | |
6330 | ||
6331 | static struct reloc_desc *find_prog_insn_relo(const struct bpf_program *prog, size_t insn_idx) | |
6332 | { | |
6333 | return bsearch(&insn_idx, prog->reloc_desc, prog->nr_reloc, | |
6334 | sizeof(*prog->reloc_desc), cmp_relo_by_insn_idx); | |
6335 | } | |
6336 | ||
6337 | static int | |
6338 | bpf_object__reloc_code(struct bpf_object *obj, struct bpf_program *main_prog, | |
6339 | struct bpf_program *prog) | |
6340 | { | |
6341 | size_t sub_insn_idx, insn_idx, new_cnt; | |
6342 | struct bpf_program *subprog; | |
6343 | struct bpf_insn *insns, *insn; | |
6344 | struct reloc_desc *relo; | |
6345 | int err; | |
6346 | ||
6347 | err = reloc_prog_func_and_line_info(obj, main_prog, prog); | |
6348 | if (err) | |
6349 | return err; | |
6350 | ||
6351 | for (insn_idx = 0; insn_idx < prog->sec_insn_cnt; insn_idx++) { | |
6352 | insn = &main_prog->insns[prog->sub_insn_off + insn_idx]; | |
6353 | if (!insn_is_subprog_call(insn)) | |
6354 | continue; | |
6355 | ||
6356 | relo = find_prog_insn_relo(prog, insn_idx); | |
6357 | if (relo && relo->type != RELO_CALL) { | |
6358 | pr_warn("prog '%s': unexpected relo for insn #%zu, type %d\n", | |
6359 | prog->name, insn_idx, relo->type); | |
6360 | return -LIBBPF_ERRNO__RELOC; | |
6361 | } | |
6362 | if (relo) { | |
6363 | /* sub-program instruction index is a combination of | |
6364 | * an offset of a symbol pointed to by relocation and | |
6365 | * call instruction's imm field; for global functions, | |
6366 | * call always has imm = -1, but for static functions | |
6367 | * relocation is against STT_SECTION and insn->imm | |
6368 | * points to a start of a static function | |
6369 | */ | |
6370 | sub_insn_idx = relo->sym_off / BPF_INSN_SZ + insn->imm + 1; | |
6371 | } else { | |
6372 | /* if subprogram call is to a static function within | |
6373 | * the same ELF section, there won't be any relocation | |
6374 | * emitted, but it also means there is no additional | |
6375 | * offset necessary, insns->imm is relative to | |
6376 | * instruction's original position within the section | |
6377 | */ | |
6378 | sub_insn_idx = prog->sec_insn_off + insn_idx + insn->imm + 1; | |
6379 | } | |
6380 | ||
6381 | /* we enforce that sub-programs should be in .text section */ | |
6382 | subprog = find_prog_by_sec_insn(obj, obj->efile.text_shndx, sub_insn_idx); | |
6383 | if (!subprog) { | |
6384 | pr_warn("prog '%s': no .text section found yet sub-program call exists\n", | |
6385 | prog->name); | |
6386 | return -LIBBPF_ERRNO__RELOC; | |
6387 | } | |
6388 | ||
6389 | /* if it's the first call instruction calling into this | |
6390 | * subprogram (meaning this subprog hasn't been processed | |
6391 | * yet) within the context of current main program: | |
6392 | * - append it at the end of main program's instructions blog; | |
6393 | * - process is recursively, while current program is put on hold; | |
6394 | * - if that subprogram calls some other not yet processes | |
6395 | * subprogram, same thing will happen recursively until | |
6396 | * there are no more unprocesses subprograms left to append | |
6397 | * and relocate. | |
6398 | */ | |
6399 | if (subprog->sub_insn_off == 0) { | |
6400 | subprog->sub_insn_off = main_prog->insns_cnt; | |
6401 | ||
6402 | new_cnt = main_prog->insns_cnt + subprog->insns_cnt; | |
6403 | insns = libbpf_reallocarray(main_prog->insns, new_cnt, sizeof(*insns)); | |
6404 | if (!insns) { | |
6405 | pr_warn("prog '%s': failed to realloc prog code\n", main_prog->name); | |
6406 | return -ENOMEM; | |
6407 | } | |
6408 | main_prog->insns = insns; | |
6409 | main_prog->insns_cnt = new_cnt; | |
6410 | ||
6411 | memcpy(main_prog->insns + subprog->sub_insn_off, subprog->insns, | |
6412 | subprog->insns_cnt * sizeof(*insns)); | |
6413 | ||
6414 | pr_debug("prog '%s': added %zu insns from sub-prog '%s'\n", | |
6415 | main_prog->name, subprog->insns_cnt, subprog->name); | |
6416 | ||
6417 | err = bpf_object__reloc_code(obj, main_prog, subprog); | |
6418 | if (err) | |
6419 | return err; | |
6420 | } | |
6421 | ||
6422 | /* main_prog->insns memory could have been re-allocated, so | |
6423 | * calculate pointer again | |
6424 | */ | |
6425 | insn = &main_prog->insns[prog->sub_insn_off + insn_idx]; | |
6426 | /* calculate correct instruction position within current main | |
6427 | * prog; each main prog can have a different set of | |
6428 | * subprograms appended (potentially in different order as | |
6429 | * well), so position of any subprog can be different for | |
6430 | * different main programs */ | |
6431 | insn->imm = subprog->sub_insn_off - (prog->sub_insn_off + insn_idx) - 1; | |
6432 | ||
6433 | if (relo) | |
6434 | relo->processed = true; | |
6435 | ||
6436 | pr_debug("prog '%s': insn #%zu relocated, imm %d points to subprog '%s' (now at %zu offset)\n", | |
6437 | prog->name, insn_idx, insn->imm, subprog->name, subprog->sub_insn_off); | |
6438 | } | |
6439 | ||
6440 | return 0; | |
6441 | } | |
6442 | ||
6443 | /* | |
6444 | * Relocate sub-program calls. | |
6445 | * | |
6446 | * Algorithm operates as follows. Each entry-point BPF program (referred to as | |
6447 | * main prog) is processed separately. For each subprog (non-entry functions, | |
6448 | * that can be called from either entry progs or other subprogs) gets their | |
6449 | * sub_insn_off reset to zero. This serves as indicator that this subprogram | |
6450 | * hasn't been yet appended and relocated within current main prog. Once its | |
6451 | * relocated, sub_insn_off will point at the position within current main prog | |
6452 | * where given subprog was appended. This will further be used to relocate all | |
6453 | * the call instructions jumping into this subprog. | |
6454 | * | |
6455 | * We start with main program and process all call instructions. If the call | |
6456 | * is into a subprog that hasn't been processed (i.e., subprog->sub_insn_off | |
6457 | * is zero), subprog instructions are appended at the end of main program's | |
6458 | * instruction array. Then main program is "put on hold" while we recursively | |
6459 | * process newly appended subprogram. If that subprogram calls into another | |
6460 | * subprogram that hasn't been appended, new subprogram is appended again to | |
6461 | * the *main* prog's instructions (subprog's instructions are always left | |
6462 | * untouched, as they need to be in unmodified state for subsequent main progs | |
6463 | * and subprog instructions are always sent only as part of a main prog) and | |
6464 | * the process continues recursively. Once all the subprogs called from a main | |
6465 | * prog or any of its subprogs are appended (and relocated), all their | |
6466 | * positions within finalized instructions array are known, so it's easy to | |
6467 | * rewrite call instructions with correct relative offsets, corresponding to | |
6468 | * desired target subprog. | |
6469 | * | |
6470 | * Its important to realize that some subprogs might not be called from some | |
6471 | * main prog and any of its called/used subprogs. Those will keep their | |
6472 | * subprog->sub_insn_off as zero at all times and won't be appended to current | |
6473 | * main prog and won't be relocated within the context of current main prog. | |
6474 | * They might still be used from other main progs later. | |
6475 | * | |
6476 | * Visually this process can be shown as below. Suppose we have two main | |
6477 | * programs mainA and mainB and BPF object contains three subprogs: subA, | |
6478 | * subB, and subC. mainA calls only subA, mainB calls only subC, but subA and | |
6479 | * subC both call subB: | |
6480 | * | |
6481 | * +--------+ +-------+ | |
6482 | * | v v | | |
6483 | * +--+---+ +--+-+-+ +---+--+ | |
6484 | * | subA | | subB | | subC | | |
6485 | * +--+---+ +------+ +---+--+ | |
6486 | * ^ ^ | |
6487 | * | | | |
6488 | * +---+-------+ +------+----+ | |
6489 | * | mainA | | mainB | | |
6490 | * +-----------+ +-----------+ | |
6491 | * | |
6492 | * We'll start relocating mainA, will find subA, append it and start | |
6493 | * processing sub A recursively: | |
6494 | * | |
6495 | * +-----------+------+ | |
6496 | * | mainA | subA | | |
6497 | * +-----------+------+ | |
6498 | * | |
6499 | * At this point we notice that subB is used from subA, so we append it and | |
6500 | * relocate (there are no further subcalls from subB): | |
6501 | * | |
6502 | * +-----------+------+------+ | |
6503 | * | mainA | subA | subB | | |
6504 | * +-----------+------+------+ | |
6505 | * | |
6506 | * At this point, we relocate subA calls, then go one level up and finish with | |
6507 | * relocatin mainA calls. mainA is done. | |
6508 | * | |
6509 | * For mainB process is similar but results in different order. We start with | |
6510 | * mainB and skip subA and subB, as mainB never calls them (at least | |
6511 | * directly), but we see subC is needed, so we append and start processing it: | |
6512 | * | |
6513 | * +-----------+------+ | |
6514 | * | mainB | subC | | |
6515 | * +-----------+------+ | |
6516 | * Now we see subC needs subB, so we go back to it, append and relocate it: | |
6517 | * | |
6518 | * +-----------+------+------+ | |
6519 | * | mainB | subC | subB | | |
6520 | * +-----------+------+------+ | |
6521 | * | |
6522 | * At this point we unwind recursion, relocate calls in subC, then in mainB. | |
6523 | */ | |
6524 | static int | |
6525 | bpf_object__relocate_calls(struct bpf_object *obj, struct bpf_program *prog) | |
6526 | { | |
6527 | struct bpf_program *subprog; | |
6528 | int i, j, err; | |
6529 | ||
c3c55696 AN |
6530 | /* mark all subprogs as not relocated (yet) within the context of |
6531 | * current main program | |
6532 | */ | |
6533 | for (i = 0; i < obj->nr_programs; i++) { | |
6534 | subprog = &obj->programs[i]; | |
6535 | if (!prog_is_subprog(obj, subprog)) | |
6536 | continue; | |
6537 | ||
6538 | subprog->sub_insn_off = 0; | |
6539 | for (j = 0; j < subprog->nr_reloc; j++) | |
6540 | if (subprog->reloc_desc[j].type == RELO_CALL) | |
6541 | subprog->reloc_desc[j].processed = false; | |
6542 | } | |
6543 | ||
6544 | err = bpf_object__reloc_code(obj, prog, prog); | |
6545 | if (err) | |
6546 | return err; | |
6547 | ||
6548 | ||
8a47a6c5 WN |
6549 | return 0; |
6550 | } | |
6551 | ||
8a47a6c5 | 6552 | static int |
ddc7c304 | 6553 | bpf_object__relocate(struct bpf_object *obj, const char *targ_btf_path) |
8a47a6c5 WN |
6554 | { |
6555 | struct bpf_program *prog; | |
6556 | size_t i; | |
6557 | int err; | |
6558 | ||
ddc7c304 AN |
6559 | if (obj->btf_ext) { |
6560 | err = bpf_object__relocate_core(obj, targ_btf_path); | |
6561 | if (err) { | |
be18010e KW |
6562 | pr_warn("failed to perform CO-RE relocations: %d\n", |
6563 | err); | |
ddc7c304 AN |
6564 | return err; |
6565 | } | |
6566 | } | |
c3c55696 AN |
6567 | /* relocate data references first for all programs and sub-programs, |
6568 | * as they don't change relative to code locations, so subsequent | |
6569 | * subprogram processing won't need to re-calculate any of them | |
9173cac3 AN |
6570 | */ |
6571 | for (i = 0; i < obj->nr_programs; i++) { | |
6572 | prog = &obj->programs[i]; | |
c3c55696 | 6573 | err = bpf_object__relocate_data(obj, prog); |
9173cac3 | 6574 | if (err) { |
9c0f8cbd AN |
6575 | pr_warn("prog '%s': failed to relocate data references: %d\n", |
6576 | prog->name, err); | |
9173cac3 AN |
6577 | return err; |
6578 | } | |
9173cac3 | 6579 | } |
c3c55696 AN |
6580 | /* now relocate subprogram calls and append used subprograms to main |
6581 | * programs; each copy of subprogram code needs to be relocated | |
6582 | * differently for each main program, because its code location might | |
6583 | * have changed | |
9173cac3 | 6584 | */ |
8a47a6c5 WN |
6585 | for (i = 0; i < obj->nr_programs; i++) { |
6586 | prog = &obj->programs[i]; | |
c3c55696 AN |
6587 | /* sub-program's sub-calls are relocated within the context of |
6588 | * its main program only | |
6589 | */ | |
6590 | if (prog_is_subprog(obj, prog)) | |
9173cac3 | 6591 | continue; |
8a47a6c5 | 6592 | |
c3c55696 | 6593 | err = bpf_object__relocate_calls(obj, prog); |
8a47a6c5 | 6594 | if (err) { |
9c0f8cbd AN |
6595 | pr_warn("prog '%s': failed to relocate calls: %d\n", |
6596 | prog->name, err); | |
8a47a6c5 WN |
6597 | return err; |
6598 | } | |
6599 | } | |
c3c55696 AN |
6600 | /* free up relocation descriptors */ |
6601 | for (i = 0; i < obj->nr_programs; i++) { | |
6602 | prog = &obj->programs[i]; | |
6603 | zfree(&prog->reloc_desc); | |
6604 | prog->nr_reloc = 0; | |
6605 | } | |
8a47a6c5 WN |
6606 | return 0; |
6607 | } | |
6608 | ||
646f02ff AN |
6609 | static int bpf_object__collect_st_ops_relos(struct bpf_object *obj, |
6610 | GElf_Shdr *shdr, Elf_Data *data); | |
6611 | ||
6612 | static int bpf_object__collect_map_relos(struct bpf_object *obj, | |
6613 | GElf_Shdr *shdr, Elf_Data *data) | |
6614 | { | |
15728ad3 AN |
6615 | const int bpf_ptr_sz = 8, host_ptr_sz = sizeof(void *); |
6616 | int i, j, nrels, new_sz; | |
063e6881 | 6617 | const struct btf_var_secinfo *vi = NULL; |
646f02ff | 6618 | const struct btf_type *sec, *var, *def; |
3168c158 | 6619 | struct bpf_map *map = NULL, *targ_map; |
646f02ff | 6620 | const struct btf_member *member; |
646f02ff AN |
6621 | const char *name, *mname; |
6622 | Elf_Data *symbols; | |
6623 | unsigned int moff; | |
6624 | GElf_Sym sym; | |
6625 | GElf_Rel rel; | |
6626 | void *tmp; | |
6627 | ||
6628 | if (!obj->efile.btf_maps_sec_btf_id || !obj->btf) | |
6629 | return -EINVAL; | |
6630 | sec = btf__type_by_id(obj->btf, obj->efile.btf_maps_sec_btf_id); | |
6631 | if (!sec) | |
6632 | return -EINVAL; | |
6633 | ||
6634 | symbols = obj->efile.symbols; | |
6635 | nrels = shdr->sh_size / shdr->sh_entsize; | |
6636 | for (i = 0; i < nrels; i++) { | |
6637 | if (!gelf_getrel(data, i, &rel)) { | |
6638 | pr_warn(".maps relo #%d: failed to get ELF relo\n", i); | |
6639 | return -LIBBPF_ERRNO__FORMAT; | |
6640 | } | |
6641 | if (!gelf_getsym(symbols, GELF_R_SYM(rel.r_info), &sym)) { | |
6642 | pr_warn(".maps relo #%d: symbol %zx not found\n", | |
6643 | i, (size_t)GELF_R_SYM(rel.r_info)); | |
6644 | return -LIBBPF_ERRNO__FORMAT; | |
6645 | } | |
88a82120 | 6646 | name = elf_sym_str(obj, sym.st_name) ?: "<?>"; |
646f02ff AN |
6647 | if (sym.st_shndx != obj->efile.btf_maps_shndx) { |
6648 | pr_warn(".maps relo #%d: '%s' isn't a BTF-defined map\n", | |
6649 | i, name); | |
6650 | return -LIBBPF_ERRNO__RELOC; | |
6651 | } | |
6652 | ||
6653 | pr_debug(".maps relo #%d: for %zd value %zd rel.r_offset %zu name %d ('%s')\n", | |
6654 | i, (ssize_t)(rel.r_info >> 32), (size_t)sym.st_value, | |
6655 | (size_t)rel.r_offset, sym.st_name, name); | |
6656 | ||
6657 | for (j = 0; j < obj->nr_maps; j++) { | |
6658 | map = &obj->maps[j]; | |
6659 | if (map->sec_idx != obj->efile.btf_maps_shndx) | |
6660 | continue; | |
6661 | ||
6662 | vi = btf_var_secinfos(sec) + map->btf_var_idx; | |
6663 | if (vi->offset <= rel.r_offset && | |
15728ad3 | 6664 | rel.r_offset + bpf_ptr_sz <= vi->offset + vi->size) |
646f02ff AN |
6665 | break; |
6666 | } | |
6667 | if (j == obj->nr_maps) { | |
6668 | pr_warn(".maps relo #%d: cannot find map '%s' at rel.r_offset %zu\n", | |
6669 | i, name, (size_t)rel.r_offset); | |
6670 | return -EINVAL; | |
6671 | } | |
6672 | ||
6673 | if (!bpf_map_type__is_map_in_map(map->def.type)) | |
6674 | return -EINVAL; | |
6675 | if (map->def.type == BPF_MAP_TYPE_HASH_OF_MAPS && | |
6676 | map->def.key_size != sizeof(int)) { | |
6677 | pr_warn(".maps relo #%d: hash-of-maps '%s' should have key size %zu.\n", | |
6678 | i, map->name, sizeof(int)); | |
6679 | return -EINVAL; | |
6680 | } | |
6681 | ||
6682 | targ_map = bpf_object__find_map_by_name(obj, name); | |
6683 | if (!targ_map) | |
6684 | return -ESRCH; | |
6685 | ||
6686 | var = btf__type_by_id(obj->btf, vi->type); | |
6687 | def = skip_mods_and_typedefs(obj->btf, var->type, NULL); | |
6688 | if (btf_vlen(def) == 0) | |
6689 | return -EINVAL; | |
6690 | member = btf_members(def) + btf_vlen(def) - 1; | |
6691 | mname = btf__name_by_offset(obj->btf, member->name_off); | |
6692 | if (strcmp(mname, "values")) | |
6693 | return -EINVAL; | |
6694 | ||
6695 | moff = btf_member_bit_offset(def, btf_vlen(def) - 1) / 8; | |
6696 | if (rel.r_offset - vi->offset < moff) | |
6697 | return -EINVAL; | |
6698 | ||
6699 | moff = rel.r_offset - vi->offset - moff; | |
15728ad3 AN |
6700 | /* here we use BPF pointer size, which is always 64 bit, as we |
6701 | * are parsing ELF that was built for BPF target | |
6702 | */ | |
6703 | if (moff % bpf_ptr_sz) | |
646f02ff | 6704 | return -EINVAL; |
15728ad3 | 6705 | moff /= bpf_ptr_sz; |
646f02ff AN |
6706 | if (moff >= map->init_slots_sz) { |
6707 | new_sz = moff + 1; | |
029258d7 | 6708 | tmp = libbpf_reallocarray(map->init_slots, new_sz, host_ptr_sz); |
646f02ff AN |
6709 | if (!tmp) |
6710 | return -ENOMEM; | |
6711 | map->init_slots = tmp; | |
6712 | memset(map->init_slots + map->init_slots_sz, 0, | |
15728ad3 | 6713 | (new_sz - map->init_slots_sz) * host_ptr_sz); |
646f02ff AN |
6714 | map->init_slots_sz = new_sz; |
6715 | } | |
6716 | map->init_slots[moff] = targ_map; | |
6717 | ||
6718 | pr_debug(".maps relo #%d: map '%s' slot [%d] points to map '%s'\n", | |
6719 | i, map->name, moff, name); | |
6720 | } | |
6721 | ||
6722 | return 0; | |
6723 | } | |
590a0088 | 6724 | |
c3c55696 | 6725 | static int cmp_relocs(const void *_a, const void *_b) |
34090915 | 6726 | { |
c3c55696 AN |
6727 | const struct reloc_desc *a = _a; |
6728 | const struct reloc_desc *b = _b; | |
34090915 | 6729 | |
c3c55696 AN |
6730 | if (a->insn_idx != b->insn_idx) |
6731 | return a->insn_idx < b->insn_idx ? -1 : 1; | |
6732 | ||
6733 | /* no two relocations should have the same insn_idx, but ... */ | |
6734 | if (a->type != b->type) | |
6735 | return a->type < b->type ? -1 : 1; | |
6736 | ||
6737 | return 0; | |
6738 | } | |
6739 | ||
6740 | static int bpf_object__collect_relos(struct bpf_object *obj) | |
6741 | { | |
6742 | int i, err; | |
34090915 | 6743 | |
1f8e2bcb AN |
6744 | for (i = 0; i < obj->efile.nr_reloc_sects; i++) { |
6745 | GElf_Shdr *shdr = &obj->efile.reloc_sects[i].shdr; | |
6746 | Elf_Data *data = obj->efile.reloc_sects[i].data; | |
34090915 | 6747 | int idx = shdr->sh_info; |
34090915 WN |
6748 | |
6749 | if (shdr->sh_type != SHT_REL) { | |
be18010e | 6750 | pr_warn("internal error at %d\n", __LINE__); |
6371ca3b | 6751 | return -LIBBPF_ERRNO__INTERNAL; |
34090915 WN |
6752 | } |
6753 | ||
c3c55696 | 6754 | if (idx == obj->efile.st_ops_shndx) |
646f02ff | 6755 | err = bpf_object__collect_st_ops_relos(obj, shdr, data); |
c3c55696 | 6756 | else if (idx == obj->efile.btf_maps_shndx) |
646f02ff | 6757 | err = bpf_object__collect_map_relos(obj, shdr, data); |
c3c55696 AN |
6758 | else |
6759 | err = bpf_object__collect_prog_relos(obj, shdr, data); | |
34090915 | 6760 | if (err) |
6371ca3b | 6761 | return err; |
34090915 | 6762 | } |
c3c55696 AN |
6763 | |
6764 | for (i = 0; i < obj->nr_programs; i++) { | |
6765 | struct bpf_program *p = &obj->programs[i]; | |
6766 | ||
6767 | if (!p->nr_reloc) | |
6768 | continue; | |
6769 | ||
6770 | qsort(p->reloc_desc, p->nr_reloc, sizeof(*p->reloc_desc), cmp_relocs); | |
6771 | } | |
34090915 WN |
6772 | return 0; |
6773 | } | |
6774 | ||
109cea5a AN |
6775 | static bool insn_is_helper_call(struct bpf_insn *insn, enum bpf_func_id *func_id) |
6776 | { | |
9b2f6fec | 6777 | if (BPF_CLASS(insn->code) == BPF_JMP && |
109cea5a AN |
6778 | BPF_OP(insn->code) == BPF_CALL && |
6779 | BPF_SRC(insn->code) == BPF_K && | |
9b2f6fec AN |
6780 | insn->src_reg == 0 && |
6781 | insn->dst_reg == 0) { | |
6782 | *func_id = insn->imm; | |
109cea5a AN |
6783 | return true; |
6784 | } | |
6785 | return false; | |
6786 | } | |
6787 | ||
6788 | static int bpf_object__sanitize_prog(struct bpf_object* obj, struct bpf_program *prog) | |
6789 | { | |
6790 | struct bpf_insn *insn = prog->insns; | |
6791 | enum bpf_func_id func_id; | |
6792 | int i; | |
6793 | ||
6794 | for (i = 0; i < prog->insns_cnt; i++, insn++) { | |
6795 | if (!insn_is_helper_call(insn, &func_id)) | |
6796 | continue; | |
6797 | ||
6798 | /* on kernels that don't yet support | |
6799 | * bpf_probe_read_{kernel,user}[_str] helpers, fall back | |
6800 | * to bpf_probe_read() which works well for old kernels | |
6801 | */ | |
6802 | switch (func_id) { | |
6803 | case BPF_FUNC_probe_read_kernel: | |
6804 | case BPF_FUNC_probe_read_user: | |
6805 | if (!kernel_supports(FEAT_PROBE_READ_KERN)) | |
6806 | insn->imm = BPF_FUNC_probe_read; | |
6807 | break; | |
6808 | case BPF_FUNC_probe_read_kernel_str: | |
6809 | case BPF_FUNC_probe_read_user_str: | |
6810 | if (!kernel_supports(FEAT_PROBE_READ_KERN)) | |
6811 | insn->imm = BPF_FUNC_probe_read_str; | |
6812 | break; | |
6813 | default: | |
6814 | break; | |
6815 | } | |
6816 | } | |
6817 | return 0; | |
6818 | } | |
6819 | ||
55cffde2 | 6820 | static int |
2993e051 | 6821 | load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, |
f0187f0b | 6822 | char *license, __u32 kern_version, int *pfd) |
55cffde2 | 6823 | { |
6aef10a4 | 6824 | struct bpf_prog_load_params load_attr = {}; |
1ce6a9fc | 6825 | char *cp, errmsg[STRERR_BUFSIZE]; |
8395f320 SF |
6826 | size_t log_buf_size = 0; |
6827 | char *log_buf = NULL; | |
5d01ab7b | 6828 | int btf_fd, ret; |
55cffde2 | 6829 | |
80b2b5c3 AM |
6830 | if (prog->type == BPF_PROG_TYPE_UNSPEC) { |
6831 | /* | |
6832 | * The program type must be set. Most likely we couldn't find a proper | |
6833 | * section definition at load time, and thus we didn't infer the type. | |
6834 | */ | |
6835 | pr_warn("prog '%s': missing BPF prog type, check ELF section name '%s'\n", | |
6836 | prog->name, prog->sec_name); | |
6837 | return -EINVAL; | |
6838 | } | |
6839 | ||
fba01a06 AN |
6840 | if (!insns || !insns_cnt) |
6841 | return -EINVAL; | |
6842 | ||
2993e051 | 6843 | load_attr.prog_type = prog->type; |
25498a19 | 6844 | /* old kernels might not support specifying expected_attach_type */ |
47b6cb4d | 6845 | if (!kernel_supports(FEAT_EXP_ATTACH_TYPE) && prog->sec_def && |
25498a19 AN |
6846 | prog->sec_def->is_exp_attach_type_optional) |
6847 | load_attr.expected_attach_type = 0; | |
6848 | else | |
6849 | load_attr.expected_attach_type = prog->expected_attach_type; | |
47b6cb4d | 6850 | if (kernel_supports(FEAT_PROG_NAME)) |
5b32a23e | 6851 | load_attr.name = prog->name; |
d7be143b | 6852 | load_attr.insns = insns; |
6aef10a4 | 6853 | load_attr.insn_cnt = insns_cnt; |
d7be143b | 6854 | load_attr.license = license; |
6aef10a4 | 6855 | load_attr.attach_btf_id = prog->attach_btf_id; |
91abb4a6 | 6856 | if (prog->attach_prog_fd) |
e7bf94db | 6857 | load_attr.attach_prog_fd = prog->attach_prog_fd; |
91abb4a6 AN |
6858 | else |
6859 | load_attr.attach_btf_obj_fd = prog->attach_btf_obj_fd; | |
6aef10a4 AN |
6860 | load_attr.attach_btf_id = prog->attach_btf_id; |
6861 | load_attr.kern_version = kern_version; | |
6862 | load_attr.prog_ifindex = prog->prog_ifindex; | |
6863 | ||
0f0e55d8 AN |
6864 | /* specify func_info/line_info only if kernel supports them */ |
6865 | btf_fd = bpf_object__btf_fd(prog->obj); | |
47b6cb4d | 6866 | if (btf_fd >= 0 && kernel_supports(FEAT_BTF_FUNC)) { |
0f0e55d8 AN |
6867 | load_attr.prog_btf_fd = btf_fd; |
6868 | load_attr.func_info = prog->func_info; | |
6869 | load_attr.func_info_rec_size = prog->func_info_rec_size; | |
6870 | load_attr.func_info_cnt = prog->func_info_cnt; | |
6871 | load_attr.line_info = prog->line_info; | |
6872 | load_attr.line_info_rec_size = prog->line_info_rec_size; | |
6873 | load_attr.line_info_cnt = prog->line_info_cnt; | |
6874 | } | |
da11b417 | 6875 | load_attr.log_level = prog->log_level; |
04656198 | 6876 | load_attr.prog_flags = prog->prog_flags; |
55cffde2 | 6877 | |
da11b417 | 6878 | retry_load: |
8395f320 SF |
6879 | if (log_buf_size) { |
6880 | log_buf = malloc(log_buf_size); | |
6881 | if (!log_buf) | |
6882 | return -ENOMEM; | |
6883 | ||
6884 | *log_buf = 0; | |
6885 | } | |
55cffde2 | 6886 | |
6aef10a4 AN |
6887 | load_attr.log_buf = log_buf; |
6888 | load_attr.log_buf_sz = log_buf_size; | |
6889 | ret = libbpf__bpf_prog_load(&load_attr); | |
55cffde2 WN |
6890 | |
6891 | if (ret >= 0) { | |
8395f320 | 6892 | if (log_buf && load_attr.log_level) |
da11b417 | 6893 | pr_debug("verifier log:\n%s", log_buf); |
5d23328d YZ |
6894 | |
6895 | if (prog->obj->rodata_map_idx >= 0 && | |
6896 | kernel_supports(FEAT_PROG_BIND_MAP)) { | |
6897 | struct bpf_map *rodata_map = | |
6898 | &prog->obj->maps[prog->obj->rodata_map_idx]; | |
6899 | ||
6900 | if (bpf_prog_bind_map(ret, bpf_map__fd(rodata_map), NULL)) { | |
6901 | cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); | |
6902 | pr_warn("prog '%s': failed to bind .rodata map: %s\n", | |
6903 | prog->name, cp); | |
6904 | /* Don't fail hard if can't bind rodata. */ | |
6905 | } | |
6906 | } | |
6907 | ||
55cffde2 WN |
6908 | *pfd = ret; |
6909 | ret = 0; | |
6910 | goto out; | |
6911 | } | |
6912 | ||
8395f320 SF |
6913 | if (!log_buf || errno == ENOSPC) { |
6914 | log_buf_size = max((size_t)BPF_LOG_BUF_SIZE, | |
6915 | log_buf_size << 1); | |
6916 | ||
da11b417 AS |
6917 | free(log_buf); |
6918 | goto retry_load; | |
6919 | } | |
ef05afa6 | 6920 | ret = errno ? -errno : -LIBBPF_ERRNO__LOAD; |
24d6a808 | 6921 | cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
be18010e | 6922 | pr_warn("load bpf program failed: %s\n", cp); |
dc3a2d25 | 6923 | pr_perm_msg(ret); |
55cffde2 | 6924 | |
6371ca3b WN |
6925 | if (log_buf && log_buf[0] != '\0') { |
6926 | ret = -LIBBPF_ERRNO__VERIFY; | |
be18010e KW |
6927 | pr_warn("-- BEGIN DUMP LOG ---\n"); |
6928 | pr_warn("\n%s\n", log_buf); | |
6929 | pr_warn("-- END LOG --\n"); | |
6aef10a4 | 6930 | } else if (load_attr.insn_cnt >= BPF_MAXINSNS) { |
be18010e | 6931 | pr_warn("Program too large (%zu insns), at most %d insns\n", |
6aef10a4 | 6932 | load_attr.insn_cnt, BPF_MAXINSNS); |
705fa219 | 6933 | ret = -LIBBPF_ERRNO__PROG2BIG; |
4f33ddb4 | 6934 | } else if (load_attr.prog_type != BPF_PROG_TYPE_KPROBE) { |
705fa219 | 6935 | /* Wrong program type? */ |
4f33ddb4 | 6936 | int fd; |
705fa219 | 6937 | |
4f33ddb4 THJ |
6938 | load_attr.prog_type = BPF_PROG_TYPE_KPROBE; |
6939 | load_attr.expected_attach_type = 0; | |
6aef10a4 AN |
6940 | load_attr.log_buf = NULL; |
6941 | load_attr.log_buf_sz = 0; | |
6942 | fd = libbpf__bpf_prog_load(&load_attr); | |
4f33ddb4 THJ |
6943 | if (fd >= 0) { |
6944 | close(fd); | |
6945 | ret = -LIBBPF_ERRNO__PROGTYPE; | |
6946 | goto out; | |
6947 | } | |
55cffde2 WN |
6948 | } |
6949 | ||
6950 | out: | |
6951 | free(log_buf); | |
6952 | return ret; | |
6953 | } | |
6954 | ||
91abb4a6 | 6955 | static int libbpf_find_attach_btf_id(struct bpf_program *prog, int *btf_obj_fd, int *btf_type_id); |
13acb508 AN |
6956 | |
6957 | int bpf_program__load(struct bpf_program *prog, char *license, __u32 kern_ver) | |
55cffde2 | 6958 | { |
91abb4a6 | 6959 | int err = 0, fd, i; |
13acb508 | 6960 | |
d9297581 | 6961 | if (prog->obj->loaded) { |
52109584 | 6962 | pr_warn("prog '%s': can't load after object was loaded\n", prog->name); |
d9297581 AN |
6963 | return -EINVAL; |
6964 | } | |
6965 | ||
ff26ce5c | 6966 | if ((prog->type == BPF_PROG_TYPE_TRACING || |
1e092a03 | 6967 | prog->type == BPF_PROG_TYPE_LSM || |
ff26ce5c | 6968 | prog->type == BPF_PROG_TYPE_EXT) && !prog->attach_btf_id) { |
91abb4a6 AN |
6969 | int btf_obj_fd = 0, btf_type_id = 0; |
6970 | ||
6971 | err = libbpf_find_attach_btf_id(prog, &btf_obj_fd, &btf_type_id); | |
6972 | if (err) | |
6973 | return err; | |
6974 | ||
6975 | prog->attach_btf_obj_fd = btf_obj_fd; | |
6976 | prog->attach_btf_id = btf_type_id; | |
13acb508 | 6977 | } |
55cffde2 | 6978 | |
b580563e WN |
6979 | if (prog->instances.nr < 0 || !prog->instances.fds) { |
6980 | if (prog->preprocessor) { | |
be18010e | 6981 | pr_warn("Internal error: can't load program '%s'\n", |
52109584 | 6982 | prog->name); |
b580563e WN |
6983 | return -LIBBPF_ERRNO__INTERNAL; |
6984 | } | |
55cffde2 | 6985 | |
b580563e WN |
6986 | prog->instances.fds = malloc(sizeof(int)); |
6987 | if (!prog->instances.fds) { | |
be18010e | 6988 | pr_warn("Not enough memory for BPF fds\n"); |
b580563e WN |
6989 | return -ENOMEM; |
6990 | } | |
6991 | prog->instances.nr = 1; | |
6992 | prog->instances.fds[0] = -1; | |
6993 | } | |
6994 | ||
6995 | if (!prog->preprocessor) { | |
6996 | if (prog->instances.nr != 1) { | |
52109584 AN |
6997 | pr_warn("prog '%s': inconsistent nr(%d) != 1\n", |
6998 | prog->name, prog->instances.nr); | |
b580563e | 6999 | } |
2993e051 | 7000 | err = load_program(prog, prog->insns, prog->insns_cnt, |
13acb508 | 7001 | license, kern_ver, &fd); |
b580563e WN |
7002 | if (!err) |
7003 | prog->instances.fds[0] = fd; | |
7004 | goto out; | |
7005 | } | |
7006 | ||
7007 | for (i = 0; i < prog->instances.nr; i++) { | |
7008 | struct bpf_prog_prep_result result; | |
7009 | bpf_program_prep_t preprocessor = prog->preprocessor; | |
7010 | ||
1ad9cbb8 | 7011 | memset(&result, 0, sizeof(result)); |
b580563e WN |
7012 | err = preprocessor(prog, i, prog->insns, |
7013 | prog->insns_cnt, &result); | |
7014 | if (err) { | |
be18010e | 7015 | pr_warn("Preprocessing the %dth instance of program '%s' failed\n", |
52109584 | 7016 | i, prog->name); |
b580563e WN |
7017 | goto out; |
7018 | } | |
7019 | ||
7020 | if (!result.new_insn_ptr || !result.new_insn_cnt) { | |
7021 | pr_debug("Skip loading the %dth instance of program '%s'\n", | |
52109584 | 7022 | i, prog->name); |
b580563e WN |
7023 | prog->instances.fds[i] = -1; |
7024 | if (result.pfd) | |
7025 | *result.pfd = -1; | |
7026 | continue; | |
7027 | } | |
7028 | ||
2993e051 | 7029 | err = load_program(prog, result.new_insn_ptr, |
13acb508 | 7030 | result.new_insn_cnt, license, kern_ver, &fd); |
b580563e | 7031 | if (err) { |
be18010e | 7032 | pr_warn("Loading the %dth instance of program '%s' failed\n", |
52109584 | 7033 | i, prog->name); |
b580563e WN |
7034 | goto out; |
7035 | } | |
7036 | ||
7037 | if (result.pfd) | |
7038 | *result.pfd = fd; | |
7039 | prog->instances.fds[i] = fd; | |
7040 | } | |
7041 | out: | |
55cffde2 | 7042 | if (err) |
52109584 | 7043 | pr_warn("failed to load program '%s'\n", prog->name); |
55cffde2 WN |
7044 | zfree(&prog->insns); |
7045 | prog->insns_cnt = 0; | |
7046 | return err; | |
7047 | } | |
7048 | ||
7049 | static int | |
60276f98 | 7050 | bpf_object__load_progs(struct bpf_object *obj, int log_level) |
55cffde2 | 7051 | { |
d9297581 | 7052 | struct bpf_program *prog; |
55cffde2 WN |
7053 | size_t i; |
7054 | int err; | |
7055 | ||
109cea5a AN |
7056 | for (i = 0; i < obj->nr_programs; i++) { |
7057 | prog = &obj->programs[i]; | |
7058 | err = bpf_object__sanitize_prog(obj, prog); | |
7059 | if (err) | |
7060 | return err; | |
7061 | } | |
7062 | ||
55cffde2 | 7063 | for (i = 0; i < obj->nr_programs; i++) { |
d9297581 | 7064 | prog = &obj->programs[i]; |
c3c55696 | 7065 | if (prog_is_subprog(obj, prog)) |
48cca7e4 | 7066 | continue; |
d9297581 | 7067 | if (!prog->load) { |
9c0f8cbd | 7068 | pr_debug("prog '%s': skipped loading\n", prog->name); |
d9297581 AN |
7069 | continue; |
7070 | } | |
7071 | prog->log_level |= log_level; | |
7072 | err = bpf_program__load(prog, obj->license, obj->kern_version); | |
55cffde2 WN |
7073 | if (err) |
7074 | return err; | |
7075 | } | |
7076 | return 0; | |
7077 | } | |
7078 | ||
25498a19 AN |
7079 | static const struct bpf_sec_def *find_sec_def(const char *sec_name); |
7080 | ||
1a5e3fb1 | 7081 | static struct bpf_object * |
5e61f270 | 7082 | __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz, |
01af3bf0 | 7083 | const struct bpf_object_open_opts *opts) |
1a5e3fb1 | 7084 | { |
8601fd42 | 7085 | const char *obj_name, *kconfig; |
dd4436bb | 7086 | struct bpf_program *prog; |
1a5e3fb1 | 7087 | struct bpf_object *obj; |
291ee02b | 7088 | char tmp_name[64]; |
6371ca3b | 7089 | int err; |
1a5e3fb1 WN |
7090 | |
7091 | if (elf_version(EV_CURRENT) == EV_NONE) { | |
be18010e KW |
7092 | pr_warn("failed to init libelf for %s\n", |
7093 | path ? : "(mem buf)"); | |
6371ca3b | 7094 | return ERR_PTR(-LIBBPF_ERRNO__LIBELF); |
1a5e3fb1 WN |
7095 | } |
7096 | ||
291ee02b AN |
7097 | if (!OPTS_VALID(opts, bpf_object_open_opts)) |
7098 | return ERR_PTR(-EINVAL); | |
7099 | ||
1aace10f | 7100 | obj_name = OPTS_GET(opts, object_name, NULL); |
291ee02b AN |
7101 | if (obj_buf) { |
7102 | if (!obj_name) { | |
7103 | snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx", | |
7104 | (unsigned long)obj_buf, | |
7105 | (unsigned long)obj_buf_sz); | |
7106 | obj_name = tmp_name; | |
7107 | } | |
7108 | path = obj_name; | |
7109 | pr_debug("loading object '%s' from buffer\n", obj_name); | |
7110 | } | |
7111 | ||
2ce8450e | 7112 | obj = bpf_object__new(path, obj_buf, obj_buf_sz, obj_name); |
6371ca3b WN |
7113 | if (IS_ERR(obj)) |
7114 | return obj; | |
1a5e3fb1 | 7115 | |
8601fd42 AN |
7116 | kconfig = OPTS_GET(opts, kconfig, NULL); |
7117 | if (kconfig) { | |
7118 | obj->kconfig = strdup(kconfig); | |
7119 | if (!obj->kconfig) | |
166750bc AN |
7120 | return ERR_PTR(-ENOMEM); |
7121 | } | |
291ee02b | 7122 | |
0d13bfce AN |
7123 | err = bpf_object__elf_init(obj); |
7124 | err = err ? : bpf_object__check_endianness(obj); | |
7125 | err = err ? : bpf_object__elf_collect(obj); | |
166750bc AN |
7126 | err = err ? : bpf_object__collect_externs(obj); |
7127 | err = err ? : bpf_object__finalize_btf(obj); | |
0d13bfce | 7128 | err = err ? : bpf_object__init_maps(obj, opts); |
c3c55696 | 7129 | err = err ? : bpf_object__collect_relos(obj); |
0d13bfce AN |
7130 | if (err) |
7131 | goto out; | |
1a5e3fb1 | 7132 | bpf_object__elf_finish(obj); |
dd4436bb AN |
7133 | |
7134 | bpf_object__for_each_program(prog, obj) { | |
52109584 | 7135 | prog->sec_def = find_sec_def(prog->sec_name); |
80b2b5c3 | 7136 | if (!prog->sec_def) { |
dd4436bb | 7137 | /* couldn't guess, but user might manually specify */ |
80b2b5c3 AM |
7138 | pr_debug("prog '%s': unrecognized ELF section name '%s'\n", |
7139 | prog->name, prog->sec_name); | |
dd4436bb | 7140 | continue; |
80b2b5c3 | 7141 | } |
dd4436bb | 7142 | |
2b288740 AS |
7143 | if (prog->sec_def->is_sleepable) |
7144 | prog->prog_flags |= BPF_F_SLEEPABLE; | |
25498a19 AN |
7145 | bpf_program__set_type(prog, prog->sec_def->prog_type); |
7146 | bpf_program__set_expected_attach_type(prog, | |
7147 | prog->sec_def->expected_attach_type); | |
7148 | ||
7149 | if (prog->sec_def->prog_type == BPF_PROG_TYPE_TRACING || | |
7150 | prog->sec_def->prog_type == BPF_PROG_TYPE_EXT) | |
166750bc | 7151 | prog->attach_prog_fd = OPTS_GET(opts, attach_prog_fd, 0); |
dd4436bb AN |
7152 | } |
7153 | ||
1a5e3fb1 WN |
7154 | return obj; |
7155 | out: | |
7156 | bpf_object__close(obj); | |
6371ca3b | 7157 | return ERR_PTR(err); |
1a5e3fb1 WN |
7158 | } |
7159 | ||
5e61f270 AN |
7160 | static struct bpf_object * |
7161 | __bpf_object__open_xattr(struct bpf_object_open_attr *attr, int flags) | |
1a5e3fb1 | 7162 | { |
e00aca65 | 7163 | DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts, |
291ee02b AN |
7164 | .relaxed_maps = flags & MAPS_RELAX_COMPAT, |
7165 | ); | |
7166 | ||
1a5e3fb1 | 7167 | /* param validation */ |
07f2d4ea | 7168 | if (!attr->file) |
1a5e3fb1 WN |
7169 | return NULL; |
7170 | ||
07f2d4ea | 7171 | pr_debug("loading %s\n", attr->file); |
291ee02b | 7172 | return __bpf_object__open(attr->file, NULL, 0, &opts); |
c034a177 JF |
7173 | } |
7174 | ||
7175 | struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr) | |
7176 | { | |
7177 | return __bpf_object__open_xattr(attr, 0); | |
07f2d4ea JK |
7178 | } |
7179 | ||
7180 | struct bpf_object *bpf_object__open(const char *path) | |
7181 | { | |
7182 | struct bpf_object_open_attr attr = { | |
7183 | .file = path, | |
7184 | .prog_type = BPF_PROG_TYPE_UNSPEC, | |
7185 | }; | |
1a5e3fb1 | 7186 | |
07f2d4ea | 7187 | return bpf_object__open_xattr(&attr); |
6c956392 WN |
7188 | } |
7189 | ||
2ce8450e | 7190 | struct bpf_object * |
01af3bf0 | 7191 | bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts) |
2ce8450e | 7192 | { |
2ce8450e AN |
7193 | if (!path) |
7194 | return ERR_PTR(-EINVAL); | |
7195 | ||
7196 | pr_debug("loading %s\n", path); | |
7197 | ||
291ee02b | 7198 | return __bpf_object__open(path, NULL, 0, opts); |
2ce8450e AN |
7199 | } |
7200 | ||
7201 | struct bpf_object * | |
7202 | bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz, | |
01af3bf0 | 7203 | const struct bpf_object_open_opts *opts) |
6c956392 | 7204 | { |
2ce8450e AN |
7205 | if (!obj_buf || obj_buf_sz == 0) |
7206 | return ERR_PTR(-EINVAL); | |
6c956392 | 7207 | |
291ee02b | 7208 | return __bpf_object__open(NULL, obj_buf, obj_buf_sz, opts); |
2ce8450e AN |
7209 | } |
7210 | ||
7211 | struct bpf_object * | |
7212 | bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz, | |
7213 | const char *name) | |
7214 | { | |
e00aca65 | 7215 | DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts, |
2ce8450e AN |
7216 | .object_name = name, |
7217 | /* wrong default, but backwards-compatible */ | |
7218 | .relaxed_maps = true, | |
7219 | ); | |
7220 | ||
7221 | /* returning NULL is wrong, but backwards-compatible */ | |
7222 | if (!obj_buf || obj_buf_sz == 0) | |
7223 | return NULL; | |
6c956392 | 7224 | |
2ce8450e | 7225 | return bpf_object__open_mem(obj_buf, obj_buf_sz, &opts); |
1a5e3fb1 WN |
7226 | } |
7227 | ||
52d3352e WN |
7228 | int bpf_object__unload(struct bpf_object *obj) |
7229 | { | |
7230 | size_t i; | |
7231 | ||
7232 | if (!obj) | |
7233 | return -EINVAL; | |
7234 | ||
590a0088 | 7235 | for (i = 0; i < obj->nr_maps; i++) { |
9d759a9b | 7236 | zclose(obj->maps[i].fd); |
590a0088 MKL |
7237 | if (obj->maps[i].st_ops) |
7238 | zfree(&obj->maps[i].st_ops->kern_vdata); | |
7239 | } | |
52d3352e | 7240 | |
55cffde2 WN |
7241 | for (i = 0; i < obj->nr_programs; i++) |
7242 | bpf_program__unload(&obj->programs[i]); | |
7243 | ||
52d3352e WN |
7244 | return 0; |
7245 | } | |
7246 | ||
0d13bfce AN |
7247 | static int bpf_object__sanitize_maps(struct bpf_object *obj) |
7248 | { | |
7249 | struct bpf_map *m; | |
7250 | ||
7251 | bpf_object__for_each_map(m, obj) { | |
7252 | if (!bpf_map__is_internal(m)) | |
7253 | continue; | |
47b6cb4d | 7254 | if (!kernel_supports(FEAT_GLOBAL_DATA)) { |
0d13bfce AN |
7255 | pr_warn("kernel doesn't support global data\n"); |
7256 | return -ENOTSUP; | |
7257 | } | |
47b6cb4d | 7258 | if (!kernel_supports(FEAT_ARRAY_MMAP)) |
0d13bfce AN |
7259 | m->def.map_flags ^= BPF_F_MMAPABLE; |
7260 | } | |
7261 | ||
7262 | return 0; | |
7263 | } | |
7264 | ||
1c0c7074 AN |
7265 | static int bpf_object__read_kallsyms_file(struct bpf_object *obj) |
7266 | { | |
7267 | char sym_type, sym_name[500]; | |
7268 | unsigned long long sym_addr; | |
7269 | struct extern_desc *ext; | |
7270 | int ret, err = 0; | |
7271 | FILE *f; | |
7272 | ||
7273 | f = fopen("/proc/kallsyms", "r"); | |
7274 | if (!f) { | |
7275 | err = -errno; | |
7276 | pr_warn("failed to open /proc/kallsyms: %d\n", err); | |
7277 | return err; | |
7278 | } | |
7279 | ||
7280 | while (true) { | |
7281 | ret = fscanf(f, "%llx %c %499s%*[^\n]\n", | |
7282 | &sym_addr, &sym_type, sym_name); | |
7283 | if (ret == EOF && feof(f)) | |
7284 | break; | |
7285 | if (ret != 3) { | |
135c783f | 7286 | pr_warn("failed to read kallsyms entry: %d\n", ret); |
1c0c7074 AN |
7287 | err = -EINVAL; |
7288 | goto out; | |
7289 | } | |
7290 | ||
7291 | ext = find_extern_by_name(obj, sym_name); | |
7292 | if (!ext || ext->type != EXT_KSYM) | |
7293 | continue; | |
7294 | ||
7295 | if (ext->is_set && ext->ksym.addr != sym_addr) { | |
7296 | pr_warn("extern (ksym) '%s' resolution is ambiguous: 0x%llx or 0x%llx\n", | |
7297 | sym_name, ext->ksym.addr, sym_addr); | |
7298 | err = -EINVAL; | |
7299 | goto out; | |
7300 | } | |
7301 | if (!ext->is_set) { | |
7302 | ext->is_set = true; | |
7303 | ext->ksym.addr = sym_addr; | |
7304 | pr_debug("extern (ksym) %s=0x%llx\n", sym_name, sym_addr); | |
7305 | } | |
7306 | } | |
7307 | ||
7308 | out: | |
7309 | fclose(f); | |
7310 | return err; | |
7311 | } | |
7312 | ||
d370bbe1 HL |
7313 | static int bpf_object__resolve_ksyms_btf_id(struct bpf_object *obj) |
7314 | { | |
7315 | struct extern_desc *ext; | |
7316 | int i, id; | |
7317 | ||
7318 | for (i = 0; i < obj->nr_extern; i++) { | |
7319 | const struct btf_type *targ_var, *targ_type; | |
7320 | __u32 targ_type_id, local_type_id; | |
7321 | const char *targ_var_name; | |
7322 | int ret; | |
7323 | ||
7324 | ext = &obj->externs[i]; | |
7325 | if (ext->type != EXT_KSYM || !ext->ksym.type_id) | |
7326 | continue; | |
7327 | ||
7328 | id = btf__find_by_name_kind(obj->btf_vmlinux, ext->name, | |
7329 | BTF_KIND_VAR); | |
7330 | if (id <= 0) { | |
7331 | pr_warn("extern (ksym) '%s': failed to find BTF ID in vmlinux BTF.\n", | |
7332 | ext->name); | |
7333 | return -ESRCH; | |
7334 | } | |
7335 | ||
7336 | /* find local type_id */ | |
7337 | local_type_id = ext->ksym.type_id; | |
7338 | ||
7339 | /* find target type_id */ | |
7340 | targ_var = btf__type_by_id(obj->btf_vmlinux, id); | |
7341 | targ_var_name = btf__name_by_offset(obj->btf_vmlinux, | |
7342 | targ_var->name_off); | |
7343 | targ_type = skip_mods_and_typedefs(obj->btf_vmlinux, | |
7344 | targ_var->type, | |
7345 | &targ_type_id); | |
7346 | ||
7347 | ret = bpf_core_types_are_compat(obj->btf, local_type_id, | |
7348 | obj->btf_vmlinux, targ_type_id); | |
7349 | if (ret <= 0) { | |
7350 | const struct btf_type *local_type; | |
7351 | const char *targ_name, *local_name; | |
7352 | ||
7353 | local_type = btf__type_by_id(obj->btf, local_type_id); | |
7354 | local_name = btf__name_by_offset(obj->btf, | |
7355 | local_type->name_off); | |
7356 | targ_name = btf__name_by_offset(obj->btf_vmlinux, | |
7357 | targ_type->name_off); | |
7358 | ||
7359 | pr_warn("extern (ksym) '%s': incompatible types, expected [%d] %s %s, but kernel has [%d] %s %s\n", | |
7360 | ext->name, local_type_id, | |
7361 | btf_kind_str(local_type), local_name, targ_type_id, | |
7362 | btf_kind_str(targ_type), targ_name); | |
7363 | return -EINVAL; | |
7364 | } | |
7365 | ||
7366 | ext->is_set = true; | |
7367 | ext->ksym.vmlinux_btf_id = id; | |
7368 | pr_debug("extern (ksym) '%s': resolved to [%d] %s %s\n", | |
7369 | ext->name, id, btf_kind_str(targ_var), targ_var_name); | |
7370 | } | |
7371 | return 0; | |
7372 | } | |
7373 | ||
166750bc | 7374 | static int bpf_object__resolve_externs(struct bpf_object *obj, |
8601fd42 | 7375 | const char *extra_kconfig) |
166750bc | 7376 | { |
1c0c7074 | 7377 | bool need_config = false, need_kallsyms = false; |
d370bbe1 | 7378 | bool need_vmlinux_btf = false; |
166750bc | 7379 | struct extern_desc *ext; |
2e33efe3 | 7380 | void *kcfg_data = NULL; |
166750bc | 7381 | int err, i; |
166750bc AN |
7382 | |
7383 | if (obj->nr_extern == 0) | |
7384 | return 0; | |
7385 | ||
2e33efe3 AN |
7386 | if (obj->kconfig_map_idx >= 0) |
7387 | kcfg_data = obj->maps[obj->kconfig_map_idx].mmaped; | |
166750bc AN |
7388 | |
7389 | for (i = 0; i < obj->nr_extern; i++) { | |
7390 | ext = &obj->externs[i]; | |
7391 | ||
2e33efe3 AN |
7392 | if (ext->type == EXT_KCFG && |
7393 | strcmp(ext->name, "LINUX_KERNEL_VERSION") == 0) { | |
7394 | void *ext_val = kcfg_data + ext->kcfg.data_off; | |
166750bc AN |
7395 | __u32 kver = get_kernel_version(); |
7396 | ||
7397 | if (!kver) { | |
7398 | pr_warn("failed to get kernel version\n"); | |
7399 | return -EINVAL; | |
7400 | } | |
2e33efe3 | 7401 | err = set_kcfg_value_num(ext, ext_val, kver); |
166750bc AN |
7402 | if (err) |
7403 | return err; | |
2e33efe3 AN |
7404 | pr_debug("extern (kcfg) %s=0x%x\n", ext->name, kver); |
7405 | } else if (ext->type == EXT_KCFG && | |
7406 | strncmp(ext->name, "CONFIG_", 7) == 0) { | |
166750bc | 7407 | need_config = true; |
1c0c7074 | 7408 | } else if (ext->type == EXT_KSYM) { |
d370bbe1 HL |
7409 | if (ext->ksym.type_id) |
7410 | need_vmlinux_btf = true; | |
7411 | else | |
7412 | need_kallsyms = true; | |
166750bc AN |
7413 | } else { |
7414 | pr_warn("unrecognized extern '%s'\n", ext->name); | |
7415 | return -EINVAL; | |
7416 | } | |
7417 | } | |
8601fd42 | 7418 | if (need_config && extra_kconfig) { |
2e33efe3 | 7419 | err = bpf_object__read_kconfig_mem(obj, extra_kconfig, kcfg_data); |
8601fd42 AN |
7420 | if (err) |
7421 | return -EINVAL; | |
7422 | need_config = false; | |
7423 | for (i = 0; i < obj->nr_extern; i++) { | |
7424 | ext = &obj->externs[i]; | |
2e33efe3 | 7425 | if (ext->type == EXT_KCFG && !ext->is_set) { |
8601fd42 AN |
7426 | need_config = true; |
7427 | break; | |
7428 | } | |
7429 | } | |
7430 | } | |
166750bc | 7431 | if (need_config) { |
2e33efe3 | 7432 | err = bpf_object__read_kconfig_file(obj, kcfg_data); |
166750bc AN |
7433 | if (err) |
7434 | return -EINVAL; | |
7435 | } | |
1c0c7074 AN |
7436 | if (need_kallsyms) { |
7437 | err = bpf_object__read_kallsyms_file(obj); | |
7438 | if (err) | |
7439 | return -EINVAL; | |
7440 | } | |
d370bbe1 HL |
7441 | if (need_vmlinux_btf) { |
7442 | err = bpf_object__resolve_ksyms_btf_id(obj); | |
7443 | if (err) | |
7444 | return -EINVAL; | |
7445 | } | |
166750bc AN |
7446 | for (i = 0; i < obj->nr_extern; i++) { |
7447 | ext = &obj->externs[i]; | |
7448 | ||
7449 | if (!ext->is_set && !ext->is_weak) { | |
7450 | pr_warn("extern %s (strong) not resolved\n", ext->name); | |
7451 | return -ESRCH; | |
7452 | } else if (!ext->is_set) { | |
7453 | pr_debug("extern %s (weak) not resolved, defaulting to zero\n", | |
7454 | ext->name); | |
7455 | } | |
7456 | } | |
7457 | ||
7458 | return 0; | |
7459 | } | |
7460 | ||
60276f98 | 7461 | int bpf_object__load_xattr(struct bpf_object_load_attr *attr) |
52d3352e | 7462 | { |
60276f98 | 7463 | struct bpf_object *obj; |
ec6d5f47 | 7464 | int err, i; |
6371ca3b | 7465 | |
60276f98 QM |
7466 | if (!attr) |
7467 | return -EINVAL; | |
7468 | obj = attr->obj; | |
52d3352e WN |
7469 | if (!obj) |
7470 | return -EINVAL; | |
7471 | ||
7472 | if (obj->loaded) { | |
d9297581 | 7473 | pr_warn("object '%s': load can't be attempted twice\n", obj->name); |
52d3352e WN |
7474 | return -EINVAL; |
7475 | } | |
7476 | ||
fd9eef1a | 7477 | err = bpf_object__probe_loading(obj); |
d370bbe1 | 7478 | err = err ? : bpf_object__load_vmlinux_btf(obj); |
8601fd42 | 7479 | err = err ? : bpf_object__resolve_externs(obj, obj->kconfig); |
0d13bfce AN |
7480 | err = err ? : bpf_object__sanitize_and_load_btf(obj); |
7481 | err = err ? : bpf_object__sanitize_maps(obj); | |
590a0088 | 7482 | err = err ? : bpf_object__init_kern_struct_ops_maps(obj); |
0d13bfce AN |
7483 | err = err ? : bpf_object__create_maps(obj); |
7484 | err = err ? : bpf_object__relocate(obj, attr->target_btf_path); | |
7485 | err = err ? : bpf_object__load_progs(obj, attr->log_level); | |
a6ed02ca | 7486 | |
4f33a53d AN |
7487 | /* clean up module BTFs */ |
7488 | for (i = 0; i < obj->btf_module_cnt; i++) { | |
91abb4a6 | 7489 | close(obj->btf_modules[i].fd); |
4f33a53d AN |
7490 | btf__free(obj->btf_modules[i].btf); |
7491 | free(obj->btf_modules[i].name); | |
7492 | } | |
7493 | free(obj->btf_modules); | |
7494 | ||
7495 | /* clean up vmlinux BTF */ | |
a6ed02ca KS |
7496 | btf__free(obj->btf_vmlinux); |
7497 | obj->btf_vmlinux = NULL; | |
7498 | ||
d9297581 AN |
7499 | obj->loaded = true; /* doesn't matter if successfully or not */ |
7500 | ||
0d13bfce AN |
7501 | if (err) |
7502 | goto out; | |
52d3352e WN |
7503 | |
7504 | return 0; | |
7505 | out: | |
ec6d5f47 THJ |
7506 | /* unpin any maps that were auto-pinned during load */ |
7507 | for (i = 0; i < obj->nr_maps; i++) | |
7508 | if (obj->maps[i].pinned && !obj->maps[i].reused) | |
7509 | bpf_map__unpin(&obj->maps[i], NULL); | |
7510 | ||
52d3352e | 7511 | bpf_object__unload(obj); |
be18010e | 7512 | pr_warn("failed to load object '%s'\n", obj->path); |
6371ca3b | 7513 | return err; |
52d3352e WN |
7514 | } |
7515 | ||
60276f98 QM |
7516 | int bpf_object__load(struct bpf_object *obj) |
7517 | { | |
7518 | struct bpf_object_load_attr attr = { | |
7519 | .obj = obj, | |
7520 | }; | |
7521 | ||
7522 | return bpf_object__load_xattr(&attr); | |
7523 | } | |
7524 | ||
196f8487 THJ |
7525 | static int make_parent_dir(const char *path) |
7526 | { | |
7527 | char *cp, errmsg[STRERR_BUFSIZE]; | |
7528 | char *dname, *dir; | |
7529 | int err = 0; | |
7530 | ||
7531 | dname = strdup(path); | |
7532 | if (dname == NULL) | |
7533 | return -ENOMEM; | |
7534 | ||
7535 | dir = dirname(dname); | |
7536 | if (mkdir(dir, 0700) && errno != EEXIST) | |
7537 | err = -errno; | |
7538 | ||
7539 | free(dname); | |
7540 | if (err) { | |
7541 | cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); | |
7542 | pr_warn("failed to mkdir %s: %s\n", path, cp); | |
7543 | } | |
7544 | return err; | |
7545 | } | |
7546 | ||
f367540c JS |
7547 | static int check_path(const char *path) |
7548 | { | |
1ce6a9fc | 7549 | char *cp, errmsg[STRERR_BUFSIZE]; |
f367540c JS |
7550 | struct statfs st_fs; |
7551 | char *dname, *dir; | |
7552 | int err = 0; | |
7553 | ||
7554 | if (path == NULL) | |
7555 | return -EINVAL; | |
7556 | ||
7557 | dname = strdup(path); | |
7558 | if (dname == NULL) | |
7559 | return -ENOMEM; | |
7560 | ||
7561 | dir = dirname(dname); | |
7562 | if (statfs(dir, &st_fs)) { | |
24d6a808 | 7563 | cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
be18010e | 7564 | pr_warn("failed to statfs %s: %s\n", dir, cp); |
f367540c JS |
7565 | err = -errno; |
7566 | } | |
7567 | free(dname); | |
7568 | ||
7569 | if (!err && st_fs.f_type != BPF_FS_MAGIC) { | |
be18010e | 7570 | pr_warn("specified path %s is not on BPF FS\n", path); |
f367540c JS |
7571 | err = -EINVAL; |
7572 | } | |
7573 | ||
7574 | return err; | |
7575 | } | |
7576 | ||
7577 | int bpf_program__pin_instance(struct bpf_program *prog, const char *path, | |
7578 | int instance) | |
7579 | { | |
1ce6a9fc | 7580 | char *cp, errmsg[STRERR_BUFSIZE]; |
f367540c JS |
7581 | int err; |
7582 | ||
196f8487 THJ |
7583 | err = make_parent_dir(path); |
7584 | if (err) | |
7585 | return err; | |
7586 | ||
f367540c JS |
7587 | err = check_path(path); |
7588 | if (err) | |
7589 | return err; | |
7590 | ||
7591 | if (prog == NULL) { | |
be18010e | 7592 | pr_warn("invalid program pointer\n"); |
f367540c JS |
7593 | return -EINVAL; |
7594 | } | |
7595 | ||
7596 | if (instance < 0 || instance >= prog->instances.nr) { | |
be18010e | 7597 | pr_warn("invalid prog instance %d of prog %s (max %d)\n", |
52109584 | 7598 | instance, prog->name, prog->instances.nr); |
f367540c JS |
7599 | return -EINVAL; |
7600 | } | |
7601 | ||
7602 | if (bpf_obj_pin(prog->instances.fds[instance], path)) { | |
23ab656b THJ |
7603 | err = -errno; |
7604 | cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); | |
be18010e | 7605 | pr_warn("failed to pin program: %s\n", cp); |
23ab656b | 7606 | return err; |
f367540c JS |
7607 | } |
7608 | pr_debug("pinned program '%s'\n", path); | |
7609 | ||
7610 | return 0; | |
7611 | } | |
7612 | ||
0c19a9fb SF |
7613 | int bpf_program__unpin_instance(struct bpf_program *prog, const char *path, |
7614 | int instance) | |
7615 | { | |
7616 | int err; | |
7617 | ||
7618 | err = check_path(path); | |
7619 | if (err) | |
7620 | return err; | |
7621 | ||
7622 | if (prog == NULL) { | |
be18010e | 7623 | pr_warn("invalid program pointer\n"); |
0c19a9fb SF |
7624 | return -EINVAL; |
7625 | } | |
7626 | ||
7627 | if (instance < 0 || instance >= prog->instances.nr) { | |
be18010e | 7628 | pr_warn("invalid prog instance %d of prog %s (max %d)\n", |
52109584 | 7629 | instance, prog->name, prog->instances.nr); |
0c19a9fb SF |
7630 | return -EINVAL; |
7631 | } | |
7632 | ||
7633 | err = unlink(path); | |
7634 | if (err != 0) | |
7635 | return -errno; | |
7636 | pr_debug("unpinned program '%s'\n", path); | |
7637 | ||
7638 | return 0; | |
7639 | } | |
7640 | ||
f367540c JS |
7641 | int bpf_program__pin(struct bpf_program *prog, const char *path) |
7642 | { | |
7643 | int i, err; | |
7644 | ||
196f8487 THJ |
7645 | err = make_parent_dir(path); |
7646 | if (err) | |
7647 | return err; | |
7648 | ||
f367540c JS |
7649 | err = check_path(path); |
7650 | if (err) | |
7651 | return err; | |
7652 | ||
7653 | if (prog == NULL) { | |
be18010e | 7654 | pr_warn("invalid program pointer\n"); |
f367540c JS |
7655 | return -EINVAL; |
7656 | } | |
7657 | ||
7658 | if (prog->instances.nr <= 0) { | |
52109584 | 7659 | pr_warn("no instances of prog %s to pin\n", prog->name); |
f367540c JS |
7660 | return -EINVAL; |
7661 | } | |
7662 | ||
fd734c5c SF |
7663 | if (prog->instances.nr == 1) { |
7664 | /* don't create subdirs when pinning single instance */ | |
7665 | return bpf_program__pin_instance(prog, path, 0); | |
7666 | } | |
7667 | ||
0c19a9fb SF |
7668 | for (i = 0; i < prog->instances.nr; i++) { |
7669 | char buf[PATH_MAX]; | |
7670 | int len; | |
7671 | ||
7672 | len = snprintf(buf, PATH_MAX, "%s/%d", path, i); | |
7673 | if (len < 0) { | |
7674 | err = -EINVAL; | |
7675 | goto err_unpin; | |
7676 | } else if (len >= PATH_MAX) { | |
7677 | err = -ENAMETOOLONG; | |
7678 | goto err_unpin; | |
7679 | } | |
7680 | ||
7681 | err = bpf_program__pin_instance(prog, buf, i); | |
7682 | if (err) | |
7683 | goto err_unpin; | |
7684 | } | |
7685 | ||
7686 | return 0; | |
7687 | ||
7688 | err_unpin: | |
7689 | for (i = i - 1; i >= 0; i--) { | |
7690 | char buf[PATH_MAX]; | |
7691 | int len; | |
7692 | ||
7693 | len = snprintf(buf, PATH_MAX, "%s/%d", path, i); | |
7694 | if (len < 0) | |
7695 | continue; | |
7696 | else if (len >= PATH_MAX) | |
7697 | continue; | |
7698 | ||
7699 | bpf_program__unpin_instance(prog, buf, i); | |
7700 | } | |
7701 | ||
7702 | rmdir(path); | |
7703 | ||
7704 | return err; | |
7705 | } | |
7706 | ||
7707 | int bpf_program__unpin(struct bpf_program *prog, const char *path) | |
7708 | { | |
7709 | int i, err; | |
7710 | ||
7711 | err = check_path(path); | |
7712 | if (err) | |
7713 | return err; | |
7714 | ||
7715 | if (prog == NULL) { | |
be18010e | 7716 | pr_warn("invalid program pointer\n"); |
0c19a9fb SF |
7717 | return -EINVAL; |
7718 | } | |
7719 | ||
7720 | if (prog->instances.nr <= 0) { | |
52109584 | 7721 | pr_warn("no instances of prog %s to pin\n", prog->name); |
0c19a9fb | 7722 | return -EINVAL; |
fd734c5c SF |
7723 | } |
7724 | ||
7725 | if (prog->instances.nr == 1) { | |
7726 | /* don't create subdirs when pinning single instance */ | |
7727 | return bpf_program__unpin_instance(prog, path, 0); | |
0c19a9fb SF |
7728 | } |
7729 | ||
f367540c JS |
7730 | for (i = 0; i < prog->instances.nr; i++) { |
7731 | char buf[PATH_MAX]; | |
7732 | int len; | |
7733 | ||
7734 | len = snprintf(buf, PATH_MAX, "%s/%d", path, i); | |
7735 | if (len < 0) | |
7736 | return -EINVAL; | |
7737 | else if (len >= PATH_MAX) | |
7738 | return -ENAMETOOLONG; | |
7739 | ||
0c19a9fb | 7740 | err = bpf_program__unpin_instance(prog, buf, i); |
f367540c JS |
7741 | if (err) |
7742 | return err; | |
7743 | } | |
7744 | ||
0c19a9fb SF |
7745 | err = rmdir(path); |
7746 | if (err) | |
7747 | return -errno; | |
7748 | ||
f367540c JS |
7749 | return 0; |
7750 | } | |
7751 | ||
b6989f35 JS |
7752 | int bpf_map__pin(struct bpf_map *map, const char *path) |
7753 | { | |
1ce6a9fc | 7754 | char *cp, errmsg[STRERR_BUFSIZE]; |
b6989f35 JS |
7755 | int err; |
7756 | ||
b6989f35 | 7757 | if (map == NULL) { |
be18010e | 7758 | pr_warn("invalid map pointer\n"); |
b6989f35 JS |
7759 | return -EINVAL; |
7760 | } | |
7761 | ||
4580b25f THJ |
7762 | if (map->pin_path) { |
7763 | if (path && strcmp(path, map->pin_path)) { | |
7764 | pr_warn("map '%s' already has pin path '%s' different from '%s'\n", | |
7765 | bpf_map__name(map), map->pin_path, path); | |
7766 | return -EINVAL; | |
7767 | } else if (map->pinned) { | |
7768 | pr_debug("map '%s' already pinned at '%s'; not re-pinning\n", | |
7769 | bpf_map__name(map), map->pin_path); | |
7770 | return 0; | |
7771 | } | |
7772 | } else { | |
7773 | if (!path) { | |
7774 | pr_warn("missing a path to pin map '%s' at\n", | |
7775 | bpf_map__name(map)); | |
7776 | return -EINVAL; | |
7777 | } else if (map->pinned) { | |
7778 | pr_warn("map '%s' already pinned\n", bpf_map__name(map)); | |
7779 | return -EEXIST; | |
7780 | } | |
7781 | ||
7782 | map->pin_path = strdup(path); | |
7783 | if (!map->pin_path) { | |
7784 | err = -errno; | |
7785 | goto out_err; | |
7786 | } | |
b6989f35 JS |
7787 | } |
7788 | ||
196f8487 THJ |
7789 | err = make_parent_dir(map->pin_path); |
7790 | if (err) | |
7791 | return err; | |
7792 | ||
4580b25f THJ |
7793 | err = check_path(map->pin_path); |
7794 | if (err) | |
7795 | return err; | |
7796 | ||
7797 | if (bpf_obj_pin(map->fd, map->pin_path)) { | |
7798 | err = -errno; | |
7799 | goto out_err; | |
7800 | } | |
7801 | ||
7802 | map->pinned = true; | |
7803 | pr_debug("pinned map '%s'\n", map->pin_path); | |
0c19a9fb | 7804 | |
b6989f35 | 7805 | return 0; |
4580b25f THJ |
7806 | |
7807 | out_err: | |
7808 | cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); | |
7809 | pr_warn("failed to pin map: %s\n", cp); | |
7810 | return err; | |
b6989f35 JS |
7811 | } |
7812 | ||
0c19a9fb SF |
7813 | int bpf_map__unpin(struct bpf_map *map, const char *path) |
7814 | { | |
7815 | int err; | |
7816 | ||
0c19a9fb | 7817 | if (map == NULL) { |
be18010e | 7818 | pr_warn("invalid map pointer\n"); |
0c19a9fb SF |
7819 | return -EINVAL; |
7820 | } | |
7821 | ||
4580b25f THJ |
7822 | if (map->pin_path) { |
7823 | if (path && strcmp(path, map->pin_path)) { | |
7824 | pr_warn("map '%s' already has pin path '%s' different from '%s'\n", | |
7825 | bpf_map__name(map), map->pin_path, path); | |
7826 | return -EINVAL; | |
7827 | } | |
7828 | path = map->pin_path; | |
7829 | } else if (!path) { | |
7830 | pr_warn("no path to unpin map '%s' from\n", | |
7831 | bpf_map__name(map)); | |
7832 | return -EINVAL; | |
7833 | } | |
7834 | ||
7835 | err = check_path(path); | |
7836 | if (err) | |
7837 | return err; | |
7838 | ||
0c19a9fb SF |
7839 | err = unlink(path); |
7840 | if (err != 0) | |
7841 | return -errno; | |
4580b25f THJ |
7842 | |
7843 | map->pinned = false; | |
7844 | pr_debug("unpinned map '%s' from '%s'\n", bpf_map__name(map), path); | |
0c19a9fb SF |
7845 | |
7846 | return 0; | |
7847 | } | |
7848 | ||
4580b25f THJ |
7849 | int bpf_map__set_pin_path(struct bpf_map *map, const char *path) |
7850 | { | |
7851 | char *new = NULL; | |
7852 | ||
7853 | if (path) { | |
7854 | new = strdup(path); | |
7855 | if (!new) | |
7856 | return -errno; | |
7857 | } | |
7858 | ||
7859 | free(map->pin_path); | |
7860 | map->pin_path = new; | |
7861 | return 0; | |
7862 | } | |
7863 | ||
7864 | const char *bpf_map__get_pin_path(const struct bpf_map *map) | |
7865 | { | |
7866 | return map->pin_path; | |
7867 | } | |
7868 | ||
7869 | bool bpf_map__is_pinned(const struct bpf_map *map) | |
7870 | { | |
7871 | return map->pinned; | |
7872 | } | |
7873 | ||
9cf309c5 THJ |
7874 | static void sanitize_pin_path(char *s) |
7875 | { | |
7876 | /* bpffs disallows periods in path names */ | |
7877 | while (*s) { | |
7878 | if (*s == '.') | |
7879 | *s = '_'; | |
7880 | s++; | |
7881 | } | |
7882 | } | |
7883 | ||
0c19a9fb | 7884 | int bpf_object__pin_maps(struct bpf_object *obj, const char *path) |
d5148d85 | 7885 | { |
d5148d85 JS |
7886 | struct bpf_map *map; |
7887 | int err; | |
7888 | ||
7889 | if (!obj) | |
7890 | return -ENOENT; | |
7891 | ||
7892 | if (!obj->loaded) { | |
be18010e | 7893 | pr_warn("object not yet loaded; load it first\n"); |
d5148d85 JS |
7894 | return -ENOENT; |
7895 | } | |
7896 | ||
f74a53d9 | 7897 | bpf_object__for_each_map(map, obj) { |
4580b25f | 7898 | char *pin_path = NULL; |
0c19a9fb | 7899 | char buf[PATH_MAX]; |
0c19a9fb | 7900 | |
4580b25f THJ |
7901 | if (path) { |
7902 | int len; | |
7903 | ||
7904 | len = snprintf(buf, PATH_MAX, "%s/%s", path, | |
7905 | bpf_map__name(map)); | |
7906 | if (len < 0) { | |
7907 | err = -EINVAL; | |
7908 | goto err_unpin_maps; | |
7909 | } else if (len >= PATH_MAX) { | |
7910 | err = -ENAMETOOLONG; | |
7911 | goto err_unpin_maps; | |
7912 | } | |
9cf309c5 | 7913 | sanitize_pin_path(buf); |
4580b25f THJ |
7914 | pin_path = buf; |
7915 | } else if (!map->pin_path) { | |
7916 | continue; | |
0c19a9fb SF |
7917 | } |
7918 | ||
4580b25f | 7919 | err = bpf_map__pin(map, pin_path); |
0c19a9fb SF |
7920 | if (err) |
7921 | goto err_unpin_maps; | |
7922 | } | |
7923 | ||
7924 | return 0; | |
7925 | ||
7926 | err_unpin_maps: | |
7927 | while ((map = bpf_map__prev(map, obj))) { | |
4580b25f | 7928 | if (!map->pin_path) |
0c19a9fb SF |
7929 | continue; |
7930 | ||
4580b25f | 7931 | bpf_map__unpin(map, NULL); |
0c19a9fb SF |
7932 | } |
7933 | ||
7934 | return err; | |
7935 | } | |
7936 | ||
7937 | int bpf_object__unpin_maps(struct bpf_object *obj, const char *path) | |
7938 | { | |
7939 | struct bpf_map *map; | |
7940 | int err; | |
7941 | ||
7942 | if (!obj) | |
7943 | return -ENOENT; | |
7944 | ||
f74a53d9 | 7945 | bpf_object__for_each_map(map, obj) { |
4580b25f | 7946 | char *pin_path = NULL; |
d5148d85 | 7947 | char buf[PATH_MAX]; |
d5148d85 | 7948 | |
4580b25f THJ |
7949 | if (path) { |
7950 | int len; | |
7951 | ||
7952 | len = snprintf(buf, PATH_MAX, "%s/%s", path, | |
7953 | bpf_map__name(map)); | |
7954 | if (len < 0) | |
7955 | return -EINVAL; | |
7956 | else if (len >= PATH_MAX) | |
7957 | return -ENAMETOOLONG; | |
9cf309c5 | 7958 | sanitize_pin_path(buf); |
4580b25f THJ |
7959 | pin_path = buf; |
7960 | } else if (!map->pin_path) { | |
7961 | continue; | |
7962 | } | |
d5148d85 | 7963 | |
4580b25f | 7964 | err = bpf_map__unpin(map, pin_path); |
d5148d85 JS |
7965 | if (err) |
7966 | return err; | |
7967 | } | |
7968 | ||
0c19a9fb SF |
7969 | return 0; |
7970 | } | |
7971 | ||
7972 | int bpf_object__pin_programs(struct bpf_object *obj, const char *path) | |
7973 | { | |
7974 | struct bpf_program *prog; | |
7975 | int err; | |
7976 | ||
7977 | if (!obj) | |
7978 | return -ENOENT; | |
7979 | ||
7980 | if (!obj->loaded) { | |
be18010e | 7981 | pr_warn("object not yet loaded; load it first\n"); |
0c19a9fb SF |
7982 | return -ENOENT; |
7983 | } | |
7984 | ||
0c19a9fb SF |
7985 | bpf_object__for_each_program(prog, obj) { |
7986 | char buf[PATH_MAX]; | |
7987 | int len; | |
7988 | ||
7989 | len = snprintf(buf, PATH_MAX, "%s/%s", path, | |
33a2c75c | 7990 | prog->pin_name); |
0c19a9fb SF |
7991 | if (len < 0) { |
7992 | err = -EINVAL; | |
7993 | goto err_unpin_programs; | |
7994 | } else if (len >= PATH_MAX) { | |
7995 | err = -ENAMETOOLONG; | |
7996 | goto err_unpin_programs; | |
7997 | } | |
7998 | ||
7999 | err = bpf_program__pin(prog, buf); | |
8000 | if (err) | |
8001 | goto err_unpin_programs; | |
8002 | } | |
8003 | ||
8004 | return 0; | |
8005 | ||
8006 | err_unpin_programs: | |
8007 | while ((prog = bpf_program__prev(prog, obj))) { | |
8008 | char buf[PATH_MAX]; | |
8009 | int len; | |
8010 | ||
8011 | len = snprintf(buf, PATH_MAX, "%s/%s", path, | |
33a2c75c | 8012 | prog->pin_name); |
0c19a9fb SF |
8013 | if (len < 0) |
8014 | continue; | |
8015 | else if (len >= PATH_MAX) | |
8016 | continue; | |
8017 | ||
8018 | bpf_program__unpin(prog, buf); | |
8019 | } | |
8020 | ||
8021 | return err; | |
8022 | } | |
8023 | ||
8024 | int bpf_object__unpin_programs(struct bpf_object *obj, const char *path) | |
8025 | { | |
8026 | struct bpf_program *prog; | |
8027 | int err; | |
8028 | ||
8029 | if (!obj) | |
8030 | return -ENOENT; | |
8031 | ||
d5148d85 JS |
8032 | bpf_object__for_each_program(prog, obj) { |
8033 | char buf[PATH_MAX]; | |
8034 | int len; | |
8035 | ||
8036 | len = snprintf(buf, PATH_MAX, "%s/%s", path, | |
33a2c75c | 8037 | prog->pin_name); |
d5148d85 JS |
8038 | if (len < 0) |
8039 | return -EINVAL; | |
8040 | else if (len >= PATH_MAX) | |
8041 | return -ENAMETOOLONG; | |
8042 | ||
0c19a9fb | 8043 | err = bpf_program__unpin(prog, buf); |
d5148d85 JS |
8044 | if (err) |
8045 | return err; | |
8046 | } | |
8047 | ||
8048 | return 0; | |
8049 | } | |
8050 | ||
0c19a9fb SF |
8051 | int bpf_object__pin(struct bpf_object *obj, const char *path) |
8052 | { | |
8053 | int err; | |
8054 | ||
8055 | err = bpf_object__pin_maps(obj, path); | |
8056 | if (err) | |
8057 | return err; | |
8058 | ||
8059 | err = bpf_object__pin_programs(obj, path); | |
8060 | if (err) { | |
8061 | bpf_object__unpin_maps(obj, path); | |
8062 | return err; | |
8063 | } | |
8064 | ||
8065 | return 0; | |
8066 | } | |
8067 | ||
2d39d7c5 AN |
8068 | static void bpf_map__destroy(struct bpf_map *map) |
8069 | { | |
8070 | if (map->clear_priv) | |
8071 | map->clear_priv(map, map->priv); | |
8072 | map->priv = NULL; | |
8073 | map->clear_priv = NULL; | |
8074 | ||
646f02ff AN |
8075 | if (map->inner_map) { |
8076 | bpf_map__destroy(map->inner_map); | |
8077 | zfree(&map->inner_map); | |
8078 | } | |
8079 | ||
8080 | zfree(&map->init_slots); | |
8081 | map->init_slots_sz = 0; | |
8082 | ||
2d39d7c5 AN |
8083 | if (map->mmaped) { |
8084 | munmap(map->mmaped, bpf_map_mmap_sz(map)); | |
8085 | map->mmaped = NULL; | |
8086 | } | |
8087 | ||
8088 | if (map->st_ops) { | |
8089 | zfree(&map->st_ops->data); | |
8090 | zfree(&map->st_ops->progs); | |
8091 | zfree(&map->st_ops->kern_func_off); | |
8092 | zfree(&map->st_ops); | |
8093 | } | |
8094 | ||
8095 | zfree(&map->name); | |
8096 | zfree(&map->pin_path); | |
8097 | ||
8098 | if (map->fd >= 0) | |
8099 | zclose(map->fd); | |
8100 | } | |
8101 | ||
1a5e3fb1 WN |
8102 | void bpf_object__close(struct bpf_object *obj) |
8103 | { | |
a5b8bd47 WN |
8104 | size_t i; |
8105 | ||
50450fc7 | 8106 | if (IS_ERR_OR_NULL(obj)) |
1a5e3fb1 WN |
8107 | return; |
8108 | ||
10931d24 WN |
8109 | if (obj->clear_priv) |
8110 | obj->clear_priv(obj, obj->priv); | |
8111 | ||
1a5e3fb1 | 8112 | bpf_object__elf_finish(obj); |
52d3352e | 8113 | bpf_object__unload(obj); |
8a138aed | 8114 | btf__free(obj->btf); |
2993e051 | 8115 | btf_ext__free(obj->btf_ext); |
1a5e3fb1 | 8116 | |
2d39d7c5 AN |
8117 | for (i = 0; i < obj->nr_maps; i++) |
8118 | bpf_map__destroy(&obj->maps[i]); | |
d859900c | 8119 | |
8601fd42 | 8120 | zfree(&obj->kconfig); |
166750bc AN |
8121 | zfree(&obj->externs); |
8122 | obj->nr_extern = 0; | |
8123 | ||
9d759a9b WN |
8124 | zfree(&obj->maps); |
8125 | obj->nr_maps = 0; | |
a5b8bd47 WN |
8126 | |
8127 | if (obj->programs && obj->nr_programs) { | |
8128 | for (i = 0; i < obj->nr_programs; i++) | |
8129 | bpf_program__exit(&obj->programs[i]); | |
8130 | } | |
8131 | zfree(&obj->programs); | |
8132 | ||
9a208eff | 8133 | list_del(&obj->list); |
1a5e3fb1 WN |
8134 | free(obj); |
8135 | } | |
aa9b1ac3 | 8136 | |
9a208eff WN |
8137 | struct bpf_object * |
8138 | bpf_object__next(struct bpf_object *prev) | |
8139 | { | |
8140 | struct bpf_object *next; | |
8141 | ||
8142 | if (!prev) | |
8143 | next = list_first_entry(&bpf_objects_list, | |
8144 | struct bpf_object, | |
8145 | list); | |
8146 | else | |
8147 | next = list_next_entry(prev, list); | |
8148 | ||
8149 | /* Empty list is noticed here so don't need checking on entry. */ | |
8150 | if (&next->list == &bpf_objects_list) | |
8151 | return NULL; | |
8152 | ||
8153 | return next; | |
8154 | } | |
8155 | ||
a324aae3 | 8156 | const char *bpf_object__name(const struct bpf_object *obj) |
acf860ae | 8157 | { |
c9e4c301 | 8158 | return obj ? obj->name : ERR_PTR(-EINVAL); |
acf860ae WN |
8159 | } |
8160 | ||
a324aae3 | 8161 | unsigned int bpf_object__kversion(const struct bpf_object *obj) |
45825d8a | 8162 | { |
a7fe0450 | 8163 | return obj ? obj->kern_version : 0; |
45825d8a WN |
8164 | } |
8165 | ||
a324aae3 | 8166 | struct btf *bpf_object__btf(const struct bpf_object *obj) |
789f6bab AI |
8167 | { |
8168 | return obj ? obj->btf : NULL; | |
8169 | } | |
8170 | ||
8a138aed MKL |
8171 | int bpf_object__btf_fd(const struct bpf_object *obj) |
8172 | { | |
8173 | return obj->btf ? btf__fd(obj->btf) : -1; | |
8174 | } | |
8175 | ||
10931d24 WN |
8176 | int bpf_object__set_priv(struct bpf_object *obj, void *priv, |
8177 | bpf_object_clear_priv_t clear_priv) | |
8178 | { | |
8179 | if (obj->priv && obj->clear_priv) | |
8180 | obj->clear_priv(obj, obj->priv); | |
8181 | ||
8182 | obj->priv = priv; | |
8183 | obj->clear_priv = clear_priv; | |
8184 | return 0; | |
8185 | } | |
8186 | ||
a324aae3 | 8187 | void *bpf_object__priv(const struct bpf_object *obj) |
10931d24 WN |
8188 | { |
8189 | return obj ? obj->priv : ERR_PTR(-EINVAL); | |
8190 | } | |
8191 | ||
eac7d845 | 8192 | static struct bpf_program * |
a324aae3 AN |
8193 | __bpf_program__iter(const struct bpf_program *p, const struct bpf_object *obj, |
8194 | bool forward) | |
aa9b1ac3 | 8195 | { |
a83d6e76 | 8196 | size_t nr_programs = obj->nr_programs; |
0c19a9fb | 8197 | ssize_t idx; |
aa9b1ac3 | 8198 | |
a83d6e76 | 8199 | if (!nr_programs) |
aa9b1ac3 | 8200 | return NULL; |
aa9b1ac3 | 8201 | |
a83d6e76 MKL |
8202 | if (!p) |
8203 | /* Iter from the beginning */ | |
8204 | return forward ? &obj->programs[0] : | |
8205 | &obj->programs[nr_programs - 1]; | |
8206 | ||
0c19a9fb | 8207 | if (p->obj != obj) { |
be18010e | 8208 | pr_warn("error: program handler doesn't match object\n"); |
aa9b1ac3 WN |
8209 | return NULL; |
8210 | } | |
8211 | ||
a83d6e76 | 8212 | idx = (p - obj->programs) + (forward ? 1 : -1); |
0c19a9fb | 8213 | if (idx >= obj->nr_programs || idx < 0) |
aa9b1ac3 WN |
8214 | return NULL; |
8215 | return &obj->programs[idx]; | |
8216 | } | |
8217 | ||
eac7d845 | 8218 | struct bpf_program * |
a324aae3 | 8219 | bpf_program__next(struct bpf_program *prev, const struct bpf_object *obj) |
eac7d845 JK |
8220 | { |
8221 | struct bpf_program *prog = prev; | |
8222 | ||
8223 | do { | |
a83d6e76 | 8224 | prog = __bpf_program__iter(prog, obj, true); |
c3c55696 | 8225 | } while (prog && prog_is_subprog(obj, prog)); |
0c19a9fb SF |
8226 | |
8227 | return prog; | |
8228 | } | |
8229 | ||
8230 | struct bpf_program * | |
a324aae3 | 8231 | bpf_program__prev(struct bpf_program *next, const struct bpf_object *obj) |
0c19a9fb SF |
8232 | { |
8233 | struct bpf_program *prog = next; | |
8234 | ||
0c19a9fb | 8235 | do { |
a83d6e76 | 8236 | prog = __bpf_program__iter(prog, obj, false); |
c3c55696 | 8237 | } while (prog && prog_is_subprog(obj, prog)); |
eac7d845 JK |
8238 | |
8239 | return prog; | |
8240 | } | |
8241 | ||
edb13ed4 ACM |
8242 | int bpf_program__set_priv(struct bpf_program *prog, void *priv, |
8243 | bpf_program_clear_priv_t clear_priv) | |
aa9b1ac3 WN |
8244 | { |
8245 | if (prog->priv && prog->clear_priv) | |
8246 | prog->clear_priv(prog, prog->priv); | |
8247 | ||
8248 | prog->priv = priv; | |
8249 | prog->clear_priv = clear_priv; | |
8250 | return 0; | |
8251 | } | |
8252 | ||
a324aae3 | 8253 | void *bpf_program__priv(const struct bpf_program *prog) |
aa9b1ac3 | 8254 | { |
be834ffb | 8255 | return prog ? prog->priv : ERR_PTR(-EINVAL); |
aa9b1ac3 WN |
8256 | } |
8257 | ||
9aba3613 JK |
8258 | void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex) |
8259 | { | |
8260 | prog->prog_ifindex = ifindex; | |
8261 | } | |
8262 | ||
01af3bf0 AN |
8263 | const char *bpf_program__name(const struct bpf_program *prog) |
8264 | { | |
8265 | return prog->name; | |
8266 | } | |
8267 | ||
52109584 AN |
8268 | const char *bpf_program__section_name(const struct bpf_program *prog) |
8269 | { | |
8270 | return prog->sec_name; | |
8271 | } | |
8272 | ||
a324aae3 | 8273 | const char *bpf_program__title(const struct bpf_program *prog, bool needs_copy) |
aa9b1ac3 WN |
8274 | { |
8275 | const char *title; | |
8276 | ||
52109584 | 8277 | title = prog->sec_name; |
715f8db9 | 8278 | if (needs_copy) { |
aa9b1ac3 WN |
8279 | title = strdup(title); |
8280 | if (!title) { | |
be18010e | 8281 | pr_warn("failed to strdup program title\n"); |
6371ca3b | 8282 | return ERR_PTR(-ENOMEM); |
aa9b1ac3 WN |
8283 | } |
8284 | } | |
8285 | ||
8286 | return title; | |
8287 | } | |
8288 | ||
d9297581 AN |
8289 | bool bpf_program__autoload(const struct bpf_program *prog) |
8290 | { | |
8291 | return prog->load; | |
8292 | } | |
8293 | ||
8294 | int bpf_program__set_autoload(struct bpf_program *prog, bool autoload) | |
8295 | { | |
8296 | if (prog->obj->loaded) | |
8297 | return -EINVAL; | |
8298 | ||
8299 | prog->load = autoload; | |
8300 | return 0; | |
8301 | } | |
8302 | ||
a324aae3 | 8303 | int bpf_program__fd(const struct bpf_program *prog) |
aa9b1ac3 | 8304 | { |
b580563e WN |
8305 | return bpf_program__nth_fd(prog, 0); |
8306 | } | |
8307 | ||
1a734efe THJ |
8308 | size_t bpf_program__size(const struct bpf_program *prog) |
8309 | { | |
9c0f8cbd | 8310 | return prog->insns_cnt * BPF_INSN_SZ; |
1a734efe THJ |
8311 | } |
8312 | ||
b580563e WN |
8313 | int bpf_program__set_prep(struct bpf_program *prog, int nr_instances, |
8314 | bpf_program_prep_t prep) | |
8315 | { | |
8316 | int *instances_fds; | |
8317 | ||
8318 | if (nr_instances <= 0 || !prep) | |
8319 | return -EINVAL; | |
8320 | ||
8321 | if (prog->instances.nr > 0 || prog->instances.fds) { | |
be18010e | 8322 | pr_warn("Can't set pre-processor after loading\n"); |
b580563e WN |
8323 | return -EINVAL; |
8324 | } | |
8325 | ||
8326 | instances_fds = malloc(sizeof(int) * nr_instances); | |
8327 | if (!instances_fds) { | |
be18010e | 8328 | pr_warn("alloc memory failed for fds\n"); |
b580563e WN |
8329 | return -ENOMEM; |
8330 | } | |
8331 | ||
8332 | /* fill all fd with -1 */ | |
8333 | memset(instances_fds, -1, sizeof(int) * nr_instances); | |
8334 | ||
8335 | prog->instances.nr = nr_instances; | |
8336 | prog->instances.fds = instances_fds; | |
8337 | prog->preprocessor = prep; | |
8338 | return 0; | |
8339 | } | |
8340 | ||
a324aae3 | 8341 | int bpf_program__nth_fd(const struct bpf_program *prog, int n) |
b580563e WN |
8342 | { |
8343 | int fd; | |
8344 | ||
1e960043 JK |
8345 | if (!prog) |
8346 | return -EINVAL; | |
8347 | ||
b580563e | 8348 | if (n >= prog->instances.nr || n < 0) { |
be18010e | 8349 | pr_warn("Can't get the %dth fd from program %s: only %d instances\n", |
52109584 | 8350 | n, prog->name, prog->instances.nr); |
b580563e WN |
8351 | return -EINVAL; |
8352 | } | |
8353 | ||
8354 | fd = prog->instances.fds[n]; | |
8355 | if (fd < 0) { | |
be18010e | 8356 | pr_warn("%dth instance of program '%s' is invalid\n", |
52109584 | 8357 | n, prog->name); |
b580563e WN |
8358 | return -ENOENT; |
8359 | } | |
8360 | ||
8361 | return fd; | |
aa9b1ac3 | 8362 | } |
9d759a9b | 8363 | |
f1eead9e AN |
8364 | enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog) |
8365 | { | |
8366 | return prog->type; | |
8367 | } | |
8368 | ||
dd26b7f5 | 8369 | void bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type) |
5f44e4c8 WN |
8370 | { |
8371 | prog->type = type; | |
8372 | } | |
8373 | ||
a324aae3 | 8374 | static bool bpf_program__is_type(const struct bpf_program *prog, |
5f44e4c8 WN |
8375 | enum bpf_prog_type type) |
8376 | { | |
8377 | return prog ? (prog->type == type) : false; | |
8378 | } | |
8379 | ||
a324aae3 AN |
8380 | #define BPF_PROG_TYPE_FNS(NAME, TYPE) \ |
8381 | int bpf_program__set_##NAME(struct bpf_program *prog) \ | |
8382 | { \ | |
8383 | if (!prog) \ | |
8384 | return -EINVAL; \ | |
8385 | bpf_program__set_type(prog, TYPE); \ | |
8386 | return 0; \ | |
8387 | } \ | |
8388 | \ | |
8389 | bool bpf_program__is_##NAME(const struct bpf_program *prog) \ | |
8390 | { \ | |
8391 | return bpf_program__is_type(prog, TYPE); \ | |
8392 | } \ | |
ed794073 | 8393 | |
7803ba73 | 8394 | BPF_PROG_TYPE_FNS(socket_filter, BPF_PROG_TYPE_SOCKET_FILTER); |
1e092a03 | 8395 | BPF_PROG_TYPE_FNS(lsm, BPF_PROG_TYPE_LSM); |
ed794073 | 8396 | BPF_PROG_TYPE_FNS(kprobe, BPF_PROG_TYPE_KPROBE); |
7803ba73 JS |
8397 | BPF_PROG_TYPE_FNS(sched_cls, BPF_PROG_TYPE_SCHED_CLS); |
8398 | BPF_PROG_TYPE_FNS(sched_act, BPF_PROG_TYPE_SCHED_ACT); | |
ed794073 | 8399 | BPF_PROG_TYPE_FNS(tracepoint, BPF_PROG_TYPE_TRACEPOINT); |
e14c93fd | 8400 | BPF_PROG_TYPE_FNS(raw_tracepoint, BPF_PROG_TYPE_RAW_TRACEPOINT); |
7803ba73 JS |
8401 | BPF_PROG_TYPE_FNS(xdp, BPF_PROG_TYPE_XDP); |
8402 | BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT); | |
12a8654b | 8403 | BPF_PROG_TYPE_FNS(tracing, BPF_PROG_TYPE_TRACING); |
590a0088 | 8404 | BPF_PROG_TYPE_FNS(struct_ops, BPF_PROG_TYPE_STRUCT_OPS); |
2db6eab1 | 8405 | BPF_PROG_TYPE_FNS(extension, BPF_PROG_TYPE_EXT); |
499dd29d | 8406 | BPF_PROG_TYPE_FNS(sk_lookup, BPF_PROG_TYPE_SK_LOOKUP); |
5f44e4c8 | 8407 | |
f1eead9e AN |
8408 | enum bpf_attach_type |
8409 | bpf_program__get_expected_attach_type(struct bpf_program *prog) | |
8410 | { | |
8411 | return prog->expected_attach_type; | |
8412 | } | |
8413 | ||
16962b24 JF |
8414 | void bpf_program__set_expected_attach_type(struct bpf_program *prog, |
8415 | enum bpf_attach_type type) | |
d7be143b AI |
8416 | { |
8417 | prog->expected_attach_type = type; | |
8418 | } | |
8419 | ||
25498a19 AN |
8420 | #define BPF_PROG_SEC_IMPL(string, ptype, eatype, eatype_optional, \ |
8421 | attachable, attach_btf) \ | |
8422 | { \ | |
8423 | .sec = string, \ | |
8424 | .len = sizeof(string) - 1, \ | |
8425 | .prog_type = ptype, \ | |
8426 | .expected_attach_type = eatype, \ | |
8427 | .is_exp_attach_type_optional = eatype_optional, \ | |
8428 | .is_attachable = attachable, \ | |
8429 | .is_attach_btf = attach_btf, \ | |
8430 | } | |
d7be143b | 8431 | |
956b620f | 8432 | /* Programs that can NOT be attached. */ |
f75a697e | 8433 | #define BPF_PROG_SEC(string, ptype) BPF_PROG_SEC_IMPL(string, ptype, 0, 0, 0, 0) |
d7be143b | 8434 | |
956b620f AI |
8435 | /* Programs that can be attached. */ |
8436 | #define BPF_APROG_SEC(string, ptype, atype) \ | |
25498a19 | 8437 | BPF_PROG_SEC_IMPL(string, ptype, atype, true, 1, 0) |
81efee75 | 8438 | |
956b620f AI |
8439 | /* Programs that must specify expected attach type at load time. */ |
8440 | #define BPF_EAPROG_SEC(string, ptype, eatype) \ | |
25498a19 | 8441 | BPF_PROG_SEC_IMPL(string, ptype, eatype, false, 1, 0) |
f75a697e AS |
8442 | |
8443 | /* Programs that use BTF to identify attach point */ | |
12a8654b | 8444 | #define BPF_PROG_BTF(string, ptype, eatype) \ |
25498a19 | 8445 | BPF_PROG_SEC_IMPL(string, ptype, eatype, false, 0, 1) |
956b620f AI |
8446 | |
8447 | /* Programs that can be attached but attach type can't be identified by section | |
8448 | * name. Kept for backward compatibility. | |
8449 | */ | |
8450 | #define BPF_APROG_COMPAT(string, ptype) BPF_PROG_SEC(string, ptype) | |
e50b0a6f | 8451 | |
d7a18ea7 AN |
8452 | #define SEC_DEF(sec_pfx, ptype, ...) { \ |
8453 | .sec = sec_pfx, \ | |
8454 | .len = sizeof(sec_pfx) - 1, \ | |
8455 | .prog_type = BPF_PROG_TYPE_##ptype, \ | |
8456 | __VA_ARGS__ \ | |
8457 | } | |
8458 | ||
d7a18ea7 AN |
8459 | static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec, |
8460 | struct bpf_program *prog); | |
8461 | static struct bpf_link *attach_tp(const struct bpf_sec_def *sec, | |
8462 | struct bpf_program *prog); | |
8463 | static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec, | |
8464 | struct bpf_program *prog); | |
8465 | static struct bpf_link *attach_trace(const struct bpf_sec_def *sec, | |
8466 | struct bpf_program *prog); | |
1e092a03 KS |
8467 | static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec, |
8468 | struct bpf_program *prog); | |
c09add2f YS |
8469 | static struct bpf_link *attach_iter(const struct bpf_sec_def *sec, |
8470 | struct bpf_program *prog); | |
d7a18ea7 | 8471 | |
d7a18ea7 | 8472 | static const struct bpf_sec_def section_defs[] = { |
956b620f | 8473 | BPF_PROG_SEC("socket", BPF_PROG_TYPE_SOCKET_FILTER), |
67d69ccd | 8474 | BPF_PROG_SEC("sk_reuseport", BPF_PROG_TYPE_SK_REUSEPORT), |
d7a18ea7 AN |
8475 | SEC_DEF("kprobe/", KPROBE, |
8476 | .attach_fn = attach_kprobe), | |
32dff6db | 8477 | BPF_PROG_SEC("uprobe/", BPF_PROG_TYPE_KPROBE), |
d7a18ea7 AN |
8478 | SEC_DEF("kretprobe/", KPROBE, |
8479 | .attach_fn = attach_kprobe), | |
32dff6db | 8480 | BPF_PROG_SEC("uretprobe/", BPF_PROG_TYPE_KPROBE), |
956b620f AI |
8481 | BPF_PROG_SEC("classifier", BPF_PROG_TYPE_SCHED_CLS), |
8482 | BPF_PROG_SEC("action", BPF_PROG_TYPE_SCHED_ACT), | |
d7a18ea7 AN |
8483 | SEC_DEF("tracepoint/", TRACEPOINT, |
8484 | .attach_fn = attach_tp), | |
8485 | SEC_DEF("tp/", TRACEPOINT, | |
8486 | .attach_fn = attach_tp), | |
8487 | SEC_DEF("raw_tracepoint/", RAW_TRACEPOINT, | |
8488 | .attach_fn = attach_raw_tp), | |
8489 | SEC_DEF("raw_tp/", RAW_TRACEPOINT, | |
8490 | .attach_fn = attach_raw_tp), | |
8491 | SEC_DEF("tp_btf/", TRACING, | |
8492 | .expected_attach_type = BPF_TRACE_RAW_TP, | |
8493 | .is_attach_btf = true, | |
8494 | .attach_fn = attach_trace), | |
8495 | SEC_DEF("fentry/", TRACING, | |
8496 | .expected_attach_type = BPF_TRACE_FENTRY, | |
8497 | .is_attach_btf = true, | |
8498 | .attach_fn = attach_trace), | |
aca228cd KS |
8499 | SEC_DEF("fmod_ret/", TRACING, |
8500 | .expected_attach_type = BPF_MODIFY_RETURN, | |
8501 | .is_attach_btf = true, | |
8502 | .attach_fn = attach_trace), | |
d7a18ea7 AN |
8503 | SEC_DEF("fexit/", TRACING, |
8504 | .expected_attach_type = BPF_TRACE_FEXIT, | |
8505 | .is_attach_btf = true, | |
8506 | .attach_fn = attach_trace), | |
2b288740 AS |
8507 | SEC_DEF("fentry.s/", TRACING, |
8508 | .expected_attach_type = BPF_TRACE_FENTRY, | |
8509 | .is_attach_btf = true, | |
8510 | .is_sleepable = true, | |
8511 | .attach_fn = attach_trace), | |
8512 | SEC_DEF("fmod_ret.s/", TRACING, | |
8513 | .expected_attach_type = BPF_MODIFY_RETURN, | |
8514 | .is_attach_btf = true, | |
8515 | .is_sleepable = true, | |
8516 | .attach_fn = attach_trace), | |
8517 | SEC_DEF("fexit.s/", TRACING, | |
8518 | .expected_attach_type = BPF_TRACE_FEXIT, | |
8519 | .is_attach_btf = true, | |
8520 | .is_sleepable = true, | |
8521 | .attach_fn = attach_trace), | |
2db6eab1 AS |
8522 | SEC_DEF("freplace/", EXT, |
8523 | .is_attach_btf = true, | |
8524 | .attach_fn = attach_trace), | |
1e092a03 KS |
8525 | SEC_DEF("lsm/", LSM, |
8526 | .is_attach_btf = true, | |
8527 | .expected_attach_type = BPF_LSM_MAC, | |
8528 | .attach_fn = attach_lsm), | |
2b288740 AS |
8529 | SEC_DEF("lsm.s/", LSM, |
8530 | .is_attach_btf = true, | |
8531 | .is_sleepable = true, | |
8532 | .expected_attach_type = BPF_LSM_MAC, | |
8533 | .attach_fn = attach_lsm), | |
c09add2f YS |
8534 | SEC_DEF("iter/", TRACING, |
8535 | .expected_attach_type = BPF_TRACE_ITER, | |
8536 | .is_attach_btf = true, | |
8537 | .attach_fn = attach_iter), | |
7a64135f | 8538 | BPF_EAPROG_SEC("xdp_devmap/", BPF_PROG_TYPE_XDP, |
27787970 | 8539 | BPF_XDP_DEVMAP), |
4be556cf LB |
8540 | BPF_EAPROG_SEC("xdp_cpumap/", BPF_PROG_TYPE_XDP, |
8541 | BPF_XDP_CPUMAP), | |
87f92ac4 | 8542 | BPF_APROG_SEC("xdp", BPF_PROG_TYPE_XDP, |
dc8698ca | 8543 | BPF_XDP), |
956b620f AI |
8544 | BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT), |
8545 | BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN), | |
8546 | BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), | |
8547 | BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), | |
8548 | BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), | |
bafa7afe AI |
8549 | BPF_APROG_SEC("cgroup_skb/ingress", BPF_PROG_TYPE_CGROUP_SKB, |
8550 | BPF_CGROUP_INET_INGRESS), | |
8551 | BPF_APROG_SEC("cgroup_skb/egress", BPF_PROG_TYPE_CGROUP_SKB, | |
8552 | BPF_CGROUP_INET_EGRESS), | |
956b620f | 8553 | BPF_APROG_COMPAT("cgroup/skb", BPF_PROG_TYPE_CGROUP_SKB), |
e8b012e9 SF |
8554 | BPF_EAPROG_SEC("cgroup/sock_create", BPF_PROG_TYPE_CGROUP_SOCK, |
8555 | BPF_CGROUP_INET_SOCK_CREATE), | |
8556 | BPF_EAPROG_SEC("cgroup/sock_release", BPF_PROG_TYPE_CGROUP_SOCK, | |
8557 | BPF_CGROUP_INET_SOCK_RELEASE), | |
956b620f AI |
8558 | BPF_APROG_SEC("cgroup/sock", BPF_PROG_TYPE_CGROUP_SOCK, |
8559 | BPF_CGROUP_INET_SOCK_CREATE), | |
8560 | BPF_EAPROG_SEC("cgroup/post_bind4", BPF_PROG_TYPE_CGROUP_SOCK, | |
8561 | BPF_CGROUP_INET4_POST_BIND), | |
8562 | BPF_EAPROG_SEC("cgroup/post_bind6", BPF_PROG_TYPE_CGROUP_SOCK, | |
8563 | BPF_CGROUP_INET6_POST_BIND), | |
8564 | BPF_APROG_SEC("cgroup/dev", BPF_PROG_TYPE_CGROUP_DEVICE, | |
8565 | BPF_CGROUP_DEVICE), | |
8566 | BPF_APROG_SEC("sockops", BPF_PROG_TYPE_SOCK_OPS, | |
8567 | BPF_CGROUP_SOCK_OPS), | |
c6f6851b AI |
8568 | BPF_APROG_SEC("sk_skb/stream_parser", BPF_PROG_TYPE_SK_SKB, |
8569 | BPF_SK_SKB_STREAM_PARSER), | |
8570 | BPF_APROG_SEC("sk_skb/stream_verdict", BPF_PROG_TYPE_SK_SKB, | |
8571 | BPF_SK_SKB_STREAM_VERDICT), | |
956b620f AI |
8572 | BPF_APROG_COMPAT("sk_skb", BPF_PROG_TYPE_SK_SKB), |
8573 | BPF_APROG_SEC("sk_msg", BPF_PROG_TYPE_SK_MSG, | |
8574 | BPF_SK_MSG_VERDICT), | |
8575 | BPF_APROG_SEC("lirc_mode2", BPF_PROG_TYPE_LIRC_MODE2, | |
8576 | BPF_LIRC_MODE2), | |
8577 | BPF_APROG_SEC("flow_dissector", BPF_PROG_TYPE_FLOW_DISSECTOR, | |
8578 | BPF_FLOW_DISSECTOR), | |
8579 | BPF_EAPROG_SEC("cgroup/bind4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, | |
8580 | BPF_CGROUP_INET4_BIND), | |
8581 | BPF_EAPROG_SEC("cgroup/bind6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, | |
8582 | BPF_CGROUP_INET6_BIND), | |
8583 | BPF_EAPROG_SEC("cgroup/connect4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, | |
8584 | BPF_CGROUP_INET4_CONNECT), | |
8585 | BPF_EAPROG_SEC("cgroup/connect6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, | |
8586 | BPF_CGROUP_INET6_CONNECT), | |
8587 | BPF_EAPROG_SEC("cgroup/sendmsg4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, | |
8588 | BPF_CGROUP_UDP4_SENDMSG), | |
8589 | BPF_EAPROG_SEC("cgroup/sendmsg6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, | |
8590 | BPF_CGROUP_UDP6_SENDMSG), | |
9bb59ac1 DB |
8591 | BPF_EAPROG_SEC("cgroup/recvmsg4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
8592 | BPF_CGROUP_UDP4_RECVMSG), | |
8593 | BPF_EAPROG_SEC("cgroup/recvmsg6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, | |
8594 | BPF_CGROUP_UDP6_RECVMSG), | |
f15ed018 DB |
8595 | BPF_EAPROG_SEC("cgroup/getpeername4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
8596 | BPF_CGROUP_INET4_GETPEERNAME), | |
8597 | BPF_EAPROG_SEC("cgroup/getpeername6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, | |
8598 | BPF_CGROUP_INET6_GETPEERNAME), | |
8599 | BPF_EAPROG_SEC("cgroup/getsockname4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, | |
8600 | BPF_CGROUP_INET4_GETSOCKNAME), | |
8601 | BPF_EAPROG_SEC("cgroup/getsockname6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, | |
8602 | BPF_CGROUP_INET6_GETSOCKNAME), | |
063cc9f0 AI |
8603 | BPF_EAPROG_SEC("cgroup/sysctl", BPF_PROG_TYPE_CGROUP_SYSCTL, |
8604 | BPF_CGROUP_SYSCTL), | |
4cdbfb59 SF |
8605 | BPF_EAPROG_SEC("cgroup/getsockopt", BPF_PROG_TYPE_CGROUP_SOCKOPT, |
8606 | BPF_CGROUP_GETSOCKOPT), | |
8607 | BPF_EAPROG_SEC("cgroup/setsockopt", BPF_PROG_TYPE_CGROUP_SOCKOPT, | |
8608 | BPF_CGROUP_SETSOCKOPT), | |
590a0088 | 8609 | BPF_PROG_SEC("struct_ops", BPF_PROG_TYPE_STRUCT_OPS), |
499dd29d JS |
8610 | BPF_EAPROG_SEC("sk_lookup/", BPF_PROG_TYPE_SK_LOOKUP, |
8611 | BPF_SK_LOOKUP), | |
583c9009 | 8612 | }; |
d7be143b | 8613 | |
956b620f | 8614 | #undef BPF_PROG_SEC_IMPL |
583c9009 | 8615 | #undef BPF_PROG_SEC |
956b620f AI |
8616 | #undef BPF_APROG_SEC |
8617 | #undef BPF_EAPROG_SEC | |
8618 | #undef BPF_APROG_COMPAT | |
d7a18ea7 | 8619 | #undef SEC_DEF |
583c9009 | 8620 | |
c76e4c22 TS |
8621 | #define MAX_TYPE_NAME_SIZE 32 |
8622 | ||
d7a18ea7 AN |
8623 | static const struct bpf_sec_def *find_sec_def(const char *sec_name) |
8624 | { | |
8625 | int i, n = ARRAY_SIZE(section_defs); | |
8626 | ||
8627 | for (i = 0; i < n; i++) { | |
8628 | if (strncmp(sec_name, | |
8629 | section_defs[i].sec, section_defs[i].len)) | |
8630 | continue; | |
8631 | return §ion_defs[i]; | |
8632 | } | |
8633 | return NULL; | |
8634 | } | |
8635 | ||
c76e4c22 TS |
8636 | static char *libbpf_get_type_names(bool attach_type) |
8637 | { | |
d7a18ea7 | 8638 | int i, len = ARRAY_SIZE(section_defs) * MAX_TYPE_NAME_SIZE; |
c76e4c22 TS |
8639 | char *buf; |
8640 | ||
8641 | buf = malloc(len); | |
8642 | if (!buf) | |
8643 | return NULL; | |
8644 | ||
8645 | buf[0] = '\0'; | |
8646 | /* Forge string buf with all available names */ | |
d7a18ea7 AN |
8647 | for (i = 0; i < ARRAY_SIZE(section_defs); i++) { |
8648 | if (attach_type && !section_defs[i].is_attachable) | |
c76e4c22 TS |
8649 | continue; |
8650 | ||
d7a18ea7 | 8651 | if (strlen(buf) + strlen(section_defs[i].sec) + 2 > len) { |
c76e4c22 TS |
8652 | free(buf); |
8653 | return NULL; | |
8654 | } | |
8655 | strcat(buf, " "); | |
d7a18ea7 | 8656 | strcat(buf, section_defs[i].sec); |
c76e4c22 TS |
8657 | } |
8658 | ||
8659 | return buf; | |
8660 | } | |
8661 | ||
b60df2a0 JK |
8662 | int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, |
8663 | enum bpf_attach_type *expected_attach_type) | |
583c9009 | 8664 | { |
d7a18ea7 | 8665 | const struct bpf_sec_def *sec_def; |
c76e4c22 | 8666 | char *type_names; |
583c9009 | 8667 | |
b60df2a0 JK |
8668 | if (!name) |
8669 | return -EINVAL; | |
583c9009 | 8670 | |
d7a18ea7 AN |
8671 | sec_def = find_sec_def(name); |
8672 | if (sec_def) { | |
8673 | *prog_type = sec_def->prog_type; | |
8674 | *expected_attach_type = sec_def->expected_attach_type; | |
b60df2a0 JK |
8675 | return 0; |
8676 | } | |
d7a18ea7 | 8677 | |
4a3d6c6a | 8678 | pr_debug("failed to guess program type from ELF section '%s'\n", name); |
c76e4c22 TS |
8679 | type_names = libbpf_get_type_names(false); |
8680 | if (type_names != NULL) { | |
3f519353 | 8681 | pr_debug("supported section(type) names are:%s\n", type_names); |
c76e4c22 TS |
8682 | free(type_names); |
8683 | } | |
8684 | ||
dd4436bb | 8685 | return -ESRCH; |
b60df2a0 | 8686 | } |
583c9009 | 8687 | |
590a0088 MKL |
8688 | static struct bpf_map *find_struct_ops_map_by_offset(struct bpf_object *obj, |
8689 | size_t offset) | |
8690 | { | |
8691 | struct bpf_map *map; | |
8692 | size_t i; | |
8693 | ||
8694 | for (i = 0; i < obj->nr_maps; i++) { | |
8695 | map = &obj->maps[i]; | |
8696 | if (!bpf_map__is_struct_ops(map)) | |
8697 | continue; | |
8698 | if (map->sec_offset <= offset && | |
8699 | offset - map->sec_offset < map->def.value_size) | |
8700 | return map; | |
8701 | } | |
8702 | ||
8703 | return NULL; | |
8704 | } | |
8705 | ||
8706 | /* Collect the reloc from ELF and populate the st_ops->progs[] */ | |
646f02ff AN |
8707 | static int bpf_object__collect_st_ops_relos(struct bpf_object *obj, |
8708 | GElf_Shdr *shdr, Elf_Data *data) | |
590a0088 MKL |
8709 | { |
8710 | const struct btf_member *member; | |
8711 | struct bpf_struct_ops *st_ops; | |
8712 | struct bpf_program *prog; | |
8713 | unsigned int shdr_idx; | |
8714 | const struct btf *btf; | |
8715 | struct bpf_map *map; | |
8716 | Elf_Data *symbols; | |
7e06aad5 | 8717 | unsigned int moff, insn_idx; |
590a0088 | 8718 | const char *name; |
1d1a3bcf | 8719 | __u32 member_idx; |
590a0088 MKL |
8720 | GElf_Sym sym; |
8721 | GElf_Rel rel; | |
8722 | int i, nrels; | |
8723 | ||
8724 | symbols = obj->efile.symbols; | |
8725 | btf = obj->btf; | |
8726 | nrels = shdr->sh_size / shdr->sh_entsize; | |
8727 | for (i = 0; i < nrels; i++) { | |
8728 | if (!gelf_getrel(data, i, &rel)) { | |
8729 | pr_warn("struct_ops reloc: failed to get %d reloc\n", i); | |
8730 | return -LIBBPF_ERRNO__FORMAT; | |
8731 | } | |
8732 | ||
8733 | if (!gelf_getsym(symbols, GELF_R_SYM(rel.r_info), &sym)) { | |
8734 | pr_warn("struct_ops reloc: symbol %zx not found\n", | |
8735 | (size_t)GELF_R_SYM(rel.r_info)); | |
8736 | return -LIBBPF_ERRNO__FORMAT; | |
8737 | } | |
8738 | ||
88a82120 | 8739 | name = elf_sym_str(obj, sym.st_name) ?: "<?>"; |
590a0088 MKL |
8740 | map = find_struct_ops_map_by_offset(obj, rel.r_offset); |
8741 | if (!map) { | |
8742 | pr_warn("struct_ops reloc: cannot find map at rel.r_offset %zu\n", | |
8743 | (size_t)rel.r_offset); | |
8744 | return -EINVAL; | |
8745 | } | |
8746 | ||
8747 | moff = rel.r_offset - map->sec_offset; | |
8748 | shdr_idx = sym.st_shndx; | |
8749 | st_ops = map->st_ops; | |
8750 | 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", | |
8751 | map->name, | |
8752 | (long long)(rel.r_info >> 32), | |
8753 | (long long)sym.st_value, | |
8754 | shdr_idx, (size_t)rel.r_offset, | |
8755 | map->sec_offset, sym.st_name, name); | |
8756 | ||
8757 | if (shdr_idx >= SHN_LORESERVE) { | |
8758 | pr_warn("struct_ops reloc %s: rel.r_offset %zu shdr_idx %u unsupported non-static function\n", | |
8759 | map->name, (size_t)rel.r_offset, shdr_idx); | |
8760 | return -LIBBPF_ERRNO__RELOC; | |
8761 | } | |
7e06aad5 AN |
8762 | if (sym.st_value % BPF_INSN_SZ) { |
8763 | pr_warn("struct_ops reloc %s: invalid target program offset %llu\n", | |
17e54b09 | 8764 | map->name, (unsigned long long)sym.st_value); |
7e06aad5 AN |
8765 | return -LIBBPF_ERRNO__FORMAT; |
8766 | } | |
8767 | insn_idx = sym.st_value / BPF_INSN_SZ; | |
590a0088 MKL |
8768 | |
8769 | member = find_member_by_offset(st_ops->type, moff * 8); | |
8770 | if (!member) { | |
8771 | pr_warn("struct_ops reloc %s: cannot find member at moff %u\n", | |
8772 | map->name, moff); | |
8773 | return -EINVAL; | |
8774 | } | |
8775 | member_idx = member - btf_members(st_ops->type); | |
8776 | name = btf__name_by_offset(btf, member->name_off); | |
8777 | ||
8778 | if (!resolve_func_ptr(btf, member->type, NULL)) { | |
8779 | pr_warn("struct_ops reloc %s: cannot relocate non func ptr %s\n", | |
8780 | map->name, name); | |
8781 | return -EINVAL; | |
8782 | } | |
8783 | ||
7e06aad5 | 8784 | prog = find_prog_by_sec_insn(obj, shdr_idx, insn_idx); |
590a0088 MKL |
8785 | if (!prog) { |
8786 | pr_warn("struct_ops reloc %s: cannot find prog at shdr_idx %u to relocate func ptr %s\n", | |
8787 | map->name, shdr_idx, name); | |
8788 | return -EINVAL; | |
8789 | } | |
8790 | ||
8791 | if (prog->type == BPF_PROG_TYPE_UNSPEC) { | |
8792 | const struct bpf_sec_def *sec_def; | |
8793 | ||
52109584 | 8794 | sec_def = find_sec_def(prog->sec_name); |
590a0088 MKL |
8795 | if (sec_def && |
8796 | sec_def->prog_type != BPF_PROG_TYPE_STRUCT_OPS) { | |
8797 | /* for pr_warn */ | |
8798 | prog->type = sec_def->prog_type; | |
8799 | goto invalid_prog; | |
8800 | } | |
8801 | ||
8802 | prog->type = BPF_PROG_TYPE_STRUCT_OPS; | |
8803 | prog->attach_btf_id = st_ops->type_id; | |
8804 | prog->expected_attach_type = member_idx; | |
8805 | } else if (prog->type != BPF_PROG_TYPE_STRUCT_OPS || | |
8806 | prog->attach_btf_id != st_ops->type_id || | |
8807 | prog->expected_attach_type != member_idx) { | |
8808 | goto invalid_prog; | |
8809 | } | |
8810 | st_ops->progs[member_idx] = prog; | |
8811 | } | |
8812 | ||
8813 | return 0; | |
8814 | ||
8815 | invalid_prog: | |
8816 | 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", | |
52109584 | 8817 | map->name, prog->name, prog->sec_name, prog->type, |
590a0088 MKL |
8818 | prog->attach_btf_id, prog->expected_attach_type, name); |
8819 | return -EINVAL; | |
8820 | } | |
8821 | ||
a6ed02ca | 8822 | #define BTF_TRACE_PREFIX "btf_trace_" |
1e092a03 | 8823 | #define BTF_LSM_PREFIX "bpf_lsm_" |
21aef70e | 8824 | #define BTF_ITER_PREFIX "bpf_iter_" |
a6ed02ca KS |
8825 | #define BTF_MAX_NAME_SIZE 128 |
8826 | ||
8827 | static int find_btf_by_prefix_kind(const struct btf *btf, const char *prefix, | |
8828 | const char *name, __u32 kind) | |
8829 | { | |
8830 | char btf_type_name[BTF_MAX_NAME_SIZE]; | |
8831 | int ret; | |
8832 | ||
8833 | ret = snprintf(btf_type_name, sizeof(btf_type_name), | |
8834 | "%s%s", prefix, name); | |
8835 | /* snprintf returns the number of characters written excluding the | |
8836 | * the terminating null. So, if >= BTF_MAX_NAME_SIZE are written, it | |
8837 | * indicates truncation. | |
8838 | */ | |
8839 | if (ret < 0 || ret >= sizeof(btf_type_name)) | |
8840 | return -ENAMETOOLONG; | |
8841 | return btf__find_by_name_kind(btf, btf_type_name, kind); | |
8842 | } | |
8843 | ||
91abb4a6 AN |
8844 | static inline int find_attach_btf_id(struct btf *btf, const char *name, |
8845 | enum bpf_attach_type attach_type) | |
a6ed02ca KS |
8846 | { |
8847 | int err; | |
8848 | ||
8849 | if (attach_type == BPF_TRACE_RAW_TP) | |
8850 | err = find_btf_by_prefix_kind(btf, BTF_TRACE_PREFIX, name, | |
8851 | BTF_KIND_TYPEDEF); | |
1e092a03 KS |
8852 | else if (attach_type == BPF_LSM_MAC) |
8853 | err = find_btf_by_prefix_kind(btf, BTF_LSM_PREFIX, name, | |
8854 | BTF_KIND_FUNC); | |
c09add2f YS |
8855 | else if (attach_type == BPF_TRACE_ITER) |
8856 | err = find_btf_by_prefix_kind(btf, BTF_ITER_PREFIX, name, | |
8857 | BTF_KIND_FUNC); | |
a6ed02ca KS |
8858 | else |
8859 | err = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC); | |
8860 | ||
8861 | return err; | |
8862 | } | |
8863 | ||
b8c54ea4 AS |
8864 | int libbpf_find_vmlinux_btf_id(const char *name, |
8865 | enum bpf_attach_type attach_type) | |
12a8654b | 8866 | { |
a6ed02ca | 8867 | struct btf *btf; |
3521ffa2 | 8868 | int err; |
12a8654b | 8869 | |
a6ed02ca | 8870 | btf = libbpf_find_kernel_btf(); |
12a8654b AS |
8871 | if (IS_ERR(btf)) { |
8872 | pr_warn("vmlinux BTF is not found\n"); | |
8873 | return -EINVAL; | |
8874 | } | |
8875 | ||
91abb4a6 AN |
8876 | err = find_attach_btf_id(btf, name, attach_type); |
8877 | if (err <= 0) | |
8878 | pr_warn("%s is not found in vmlinux BTF\n", name); | |
8879 | ||
3521ffa2 AN |
8880 | btf__free(btf); |
8881 | return err; | |
b8c54ea4 AS |
8882 | } |
8883 | ||
e7bf94db AS |
8884 | static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd) |
8885 | { | |
8886 | struct bpf_prog_info_linear *info_linear; | |
8887 | struct bpf_prog_info *info; | |
8888 | struct btf *btf = NULL; | |
8889 | int err = -EINVAL; | |
8890 | ||
8891 | info_linear = bpf_program__get_prog_info_linear(attach_prog_fd, 0); | |
8892 | if (IS_ERR_OR_NULL(info_linear)) { | |
8893 | pr_warn("failed get_prog_info_linear for FD %d\n", | |
8894 | attach_prog_fd); | |
8895 | return -EINVAL; | |
8896 | } | |
8897 | info = &info_linear->info; | |
8898 | if (!info->btf_id) { | |
8899 | pr_warn("The target program doesn't have BTF\n"); | |
8900 | goto out; | |
8901 | } | |
8902 | if (btf__get_from_id(info->btf_id, &btf)) { | |
8903 | pr_warn("Failed to get BTF of the program\n"); | |
8904 | goto out; | |
8905 | } | |
8906 | err = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC); | |
8907 | btf__free(btf); | |
8908 | if (err <= 0) { | |
8909 | pr_warn("%s is not found in prog's BTF\n", name); | |
8910 | goto out; | |
8911 | } | |
8912 | out: | |
8913 | free(info_linear); | |
8914 | return err; | |
8915 | } | |
8916 | ||
91abb4a6 AN |
8917 | static int find_kernel_btf_id(struct bpf_object *obj, const char *attach_name, |
8918 | enum bpf_attach_type attach_type, | |
8919 | int *btf_obj_fd, int *btf_type_id) | |
8920 | { | |
8921 | int ret, i; | |
8922 | ||
8923 | ret = find_attach_btf_id(obj->btf_vmlinux, attach_name, attach_type); | |
8924 | if (ret > 0) { | |
8925 | *btf_obj_fd = 0; /* vmlinux BTF */ | |
8926 | *btf_type_id = ret; | |
8927 | return 0; | |
8928 | } | |
8929 | if (ret != -ENOENT) | |
8930 | return ret; | |
8931 | ||
8932 | ret = load_module_btfs(obj); | |
8933 | if (ret) | |
8934 | return ret; | |
8935 | ||
8936 | for (i = 0; i < obj->btf_module_cnt; i++) { | |
8937 | const struct module_btf *mod = &obj->btf_modules[i]; | |
8938 | ||
8939 | ret = find_attach_btf_id(mod->btf, attach_name, attach_type); | |
8940 | if (ret > 0) { | |
8941 | *btf_obj_fd = mod->fd; | |
8942 | *btf_type_id = ret; | |
8943 | return 0; | |
8944 | } | |
8945 | if (ret == -ENOENT) | |
8946 | continue; | |
8947 | ||
8948 | return ret; | |
8949 | } | |
8950 | ||
8951 | return -ESRCH; | |
8952 | } | |
8953 | ||
8954 | static int libbpf_find_attach_btf_id(struct bpf_program *prog, int *btf_obj_fd, int *btf_type_id) | |
b8c54ea4 | 8955 | { |
a6ed02ca KS |
8956 | enum bpf_attach_type attach_type = prog->expected_attach_type; |
8957 | __u32 attach_prog_fd = prog->attach_prog_fd; | |
91abb4a6 AN |
8958 | const char *name = prog->sec_name, *attach_name; |
8959 | const struct bpf_sec_def *sec = NULL; | |
b8c54ea4 AS |
8960 | int i, err; |
8961 | ||
12a8654b | 8962 | if (!name) |
b8c54ea4 | 8963 | return -EINVAL; |
12a8654b | 8964 | |
d7a18ea7 AN |
8965 | for (i = 0; i < ARRAY_SIZE(section_defs); i++) { |
8966 | if (!section_defs[i].is_attach_btf) | |
12a8654b | 8967 | continue; |
d7a18ea7 | 8968 | if (strncmp(name, section_defs[i].sec, section_defs[i].len)) |
12a8654b | 8969 | continue; |
91abb4a6 AN |
8970 | |
8971 | sec = §ion_defs[i]; | |
8972 | break; | |
8973 | } | |
8974 | ||
8975 | if (!sec) { | |
8976 | pr_warn("failed to identify BTF ID based on ELF section name '%s'\n", name); | |
8977 | return -ESRCH; | |
8978 | } | |
8979 | attach_name = name + sec->len; | |
8980 | ||
8981 | /* BPF program's BTF ID */ | |
8982 | if (attach_prog_fd) { | |
8983 | err = libbpf_find_prog_btf_id(attach_name, attach_prog_fd); | |
8984 | if (err < 0) { | |
8985 | pr_warn("failed to find BPF program (FD %d) BTF ID for '%s': %d\n", | |
8986 | attach_prog_fd, attach_name, err); | |
8987 | return err; | |
8988 | } | |
8989 | *btf_obj_fd = 0; | |
8990 | *btf_type_id = err; | |
8991 | return 0; | |
8992 | } | |
8993 | ||
8994 | /* kernel/module BTF ID */ | |
8995 | err = find_kernel_btf_id(prog->obj, attach_name, attach_type, btf_obj_fd, btf_type_id); | |
8996 | if (err) { | |
8997 | pr_warn("failed to find kernel BTF type ID of '%s': %d\n", attach_name, err); | |
b8c54ea4 | 8998 | return err; |
12a8654b | 8999 | } |
91abb4a6 | 9000 | return 0; |
12a8654b AS |
9001 | } |
9002 | ||
956b620f AI |
9003 | int libbpf_attach_type_by_name(const char *name, |
9004 | enum bpf_attach_type *attach_type) | |
9005 | { | |
c76e4c22 | 9006 | char *type_names; |
956b620f AI |
9007 | int i; |
9008 | ||
9009 | if (!name) | |
9010 | return -EINVAL; | |
9011 | ||
d7a18ea7 AN |
9012 | for (i = 0; i < ARRAY_SIZE(section_defs); i++) { |
9013 | if (strncmp(name, section_defs[i].sec, section_defs[i].len)) | |
956b620f | 9014 | continue; |
d7a18ea7 | 9015 | if (!section_defs[i].is_attachable) |
956b620f | 9016 | return -EINVAL; |
25498a19 | 9017 | *attach_type = section_defs[i].expected_attach_type; |
956b620f AI |
9018 | return 0; |
9019 | } | |
4a3d6c6a | 9020 | pr_debug("failed to guess attach type based on ELF section name '%s'\n", name); |
c76e4c22 TS |
9021 | type_names = libbpf_get_type_names(true); |
9022 | if (type_names != NULL) { | |
4a3d6c6a | 9023 | pr_debug("attachable section(type) names are:%s\n", type_names); |
c76e4c22 TS |
9024 | free(type_names); |
9025 | } | |
9026 | ||
956b620f AI |
9027 | return -EINVAL; |
9028 | } | |
9029 | ||
a324aae3 | 9030 | int bpf_map__fd(const struct bpf_map *map) |
9d759a9b | 9031 | { |
6e009e65 | 9032 | return map ? map->fd : -EINVAL; |
9d759a9b WN |
9033 | } |
9034 | ||
a324aae3 | 9035 | const struct bpf_map_def *bpf_map__def(const struct bpf_map *map) |
9d759a9b | 9036 | { |
53897a78 | 9037 | return map ? &map->def : ERR_PTR(-EINVAL); |
9d759a9b WN |
9038 | } |
9039 | ||
a324aae3 | 9040 | const char *bpf_map__name(const struct bpf_map *map) |
561bbcca | 9041 | { |
009ad5d5 | 9042 | return map ? map->name : NULL; |
561bbcca WN |
9043 | } |
9044 | ||
1bdb6c9a AN |
9045 | enum bpf_map_type bpf_map__type(const struct bpf_map *map) |
9046 | { | |
9047 | return map->def.type; | |
9048 | } | |
9049 | ||
9050 | int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type) | |
9051 | { | |
9052 | if (map->fd >= 0) | |
9053 | return -EBUSY; | |
9054 | map->def.type = type; | |
9055 | return 0; | |
9056 | } | |
9057 | ||
9058 | __u32 bpf_map__map_flags(const struct bpf_map *map) | |
9059 | { | |
9060 | return map->def.map_flags; | |
9061 | } | |
9062 | ||
9063 | int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags) | |
9064 | { | |
9065 | if (map->fd >= 0) | |
9066 | return -EBUSY; | |
9067 | map->def.map_flags = flags; | |
9068 | return 0; | |
9069 | } | |
9070 | ||
9071 | __u32 bpf_map__numa_node(const struct bpf_map *map) | |
9072 | { | |
9073 | return map->numa_node; | |
9074 | } | |
9075 | ||
9076 | int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node) | |
9077 | { | |
9078 | if (map->fd >= 0) | |
9079 | return -EBUSY; | |
9080 | map->numa_node = numa_node; | |
9081 | return 0; | |
9082 | } | |
9083 | ||
9084 | __u32 bpf_map__key_size(const struct bpf_map *map) | |
9085 | { | |
9086 | return map->def.key_size; | |
9087 | } | |
9088 | ||
9089 | int bpf_map__set_key_size(struct bpf_map *map, __u32 size) | |
9090 | { | |
9091 | if (map->fd >= 0) | |
9092 | return -EBUSY; | |
9093 | map->def.key_size = size; | |
9094 | return 0; | |
9095 | } | |
9096 | ||
9097 | __u32 bpf_map__value_size(const struct bpf_map *map) | |
9098 | { | |
9099 | return map->def.value_size; | |
9100 | } | |
9101 | ||
9102 | int bpf_map__set_value_size(struct bpf_map *map, __u32 size) | |
9103 | { | |
9104 | if (map->fd >= 0) | |
9105 | return -EBUSY; | |
9106 | map->def.value_size = size; | |
9107 | return 0; | |
9108 | } | |
9109 | ||
5b891af7 | 9110 | __u32 bpf_map__btf_key_type_id(const struct bpf_map *map) |
8a138aed | 9111 | { |
61746dbe | 9112 | return map ? map->btf_key_type_id : 0; |
8a138aed MKL |
9113 | } |
9114 | ||
5b891af7 | 9115 | __u32 bpf_map__btf_value_type_id(const struct bpf_map *map) |
8a138aed | 9116 | { |
61746dbe | 9117 | return map ? map->btf_value_type_id : 0; |
8a138aed MKL |
9118 | } |
9119 | ||
edb13ed4 ACM |
9120 | int bpf_map__set_priv(struct bpf_map *map, void *priv, |
9121 | bpf_map_clear_priv_t clear_priv) | |
9d759a9b WN |
9122 | { |
9123 | if (!map) | |
9124 | return -EINVAL; | |
9125 | ||
9126 | if (map->priv) { | |
9127 | if (map->clear_priv) | |
9128 | map->clear_priv(map, map->priv); | |
9129 | } | |
9130 | ||
9131 | map->priv = priv; | |
9132 | map->clear_priv = clear_priv; | |
9133 | return 0; | |
9134 | } | |
9135 | ||
a324aae3 | 9136 | void *bpf_map__priv(const struct bpf_map *map) |
9d759a9b | 9137 | { |
b4cbfa56 | 9138 | return map ? map->priv : ERR_PTR(-EINVAL); |
9d759a9b WN |
9139 | } |
9140 | ||
e2842be5 THJ |
9141 | int bpf_map__set_initial_value(struct bpf_map *map, |
9142 | const void *data, size_t size) | |
9143 | { | |
9144 | if (!map->mmaped || map->libbpf_type == LIBBPF_MAP_KCONFIG || | |
9145 | size != map->def.value_size || map->fd >= 0) | |
9146 | return -EINVAL; | |
9147 | ||
9148 | memcpy(map->mmaped, data, size); | |
9149 | return 0; | |
9150 | } | |
9151 | ||
a324aae3 | 9152 | bool bpf_map__is_offload_neutral(const struct bpf_map *map) |
f83fb22c JK |
9153 | { |
9154 | return map->def.type == BPF_MAP_TYPE_PERF_EVENT_ARRAY; | |
9155 | } | |
9156 | ||
a324aae3 | 9157 | bool bpf_map__is_internal(const struct bpf_map *map) |
d859900c DB |
9158 | { |
9159 | return map->libbpf_type != LIBBPF_MAP_UNSPEC; | |
9160 | } | |
9161 | ||
1bdb6c9a AN |
9162 | __u32 bpf_map__ifindex(const struct bpf_map *map) |
9163 | { | |
9164 | return map->map_ifindex; | |
9165 | } | |
9166 | ||
9167 | int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex) | |
9aba3613 | 9168 | { |
1bdb6c9a AN |
9169 | if (map->fd >= 0) |
9170 | return -EBUSY; | |
9aba3613 | 9171 | map->map_ifindex = ifindex; |
1bdb6c9a | 9172 | return 0; |
9aba3613 JK |
9173 | } |
9174 | ||
addb9fc9 NS |
9175 | int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd) |
9176 | { | |
9177 | if (!bpf_map_type__is_map_in_map(map->def.type)) { | |
be18010e | 9178 | pr_warn("error: unsupported map type\n"); |
addb9fc9 NS |
9179 | return -EINVAL; |
9180 | } | |
9181 | if (map->inner_map_fd != -1) { | |
be18010e | 9182 | pr_warn("error: inner_map_fd already specified\n"); |
addb9fc9 NS |
9183 | return -EINVAL; |
9184 | } | |
9185 | map->inner_map_fd = fd; | |
9186 | return 0; | |
9187 | } | |
9188 | ||
0c19a9fb | 9189 | static struct bpf_map * |
a324aae3 | 9190 | __bpf_map__iter(const struct bpf_map *m, const struct bpf_object *obj, int i) |
9d759a9b | 9191 | { |
0c19a9fb | 9192 | ssize_t idx; |
9d759a9b WN |
9193 | struct bpf_map *s, *e; |
9194 | ||
9195 | if (!obj || !obj->maps) | |
9196 | return NULL; | |
9197 | ||
9198 | s = obj->maps; | |
9199 | e = obj->maps + obj->nr_maps; | |
9200 | ||
0c19a9fb | 9201 | if ((m < s) || (m >= e)) { |
be18010e KW |
9202 | pr_warn("error in %s: map handler doesn't belong to object\n", |
9203 | __func__); | |
9d759a9b WN |
9204 | return NULL; |
9205 | } | |
9206 | ||
0c19a9fb SF |
9207 | idx = (m - obj->maps) + i; |
9208 | if (idx >= obj->nr_maps || idx < 0) | |
9d759a9b WN |
9209 | return NULL; |
9210 | return &obj->maps[idx]; | |
9211 | } | |
561bbcca | 9212 | |
0c19a9fb | 9213 | struct bpf_map * |
a324aae3 | 9214 | bpf_map__next(const struct bpf_map *prev, const struct bpf_object *obj) |
0c19a9fb SF |
9215 | { |
9216 | if (prev == NULL) | |
9217 | return obj->maps; | |
9218 | ||
9219 | return __bpf_map__iter(prev, obj, 1); | |
9220 | } | |
9221 | ||
9222 | struct bpf_map * | |
a324aae3 | 9223 | bpf_map__prev(const struct bpf_map *next, const struct bpf_object *obj) |
0c19a9fb SF |
9224 | { |
9225 | if (next == NULL) { | |
9226 | if (!obj->nr_maps) | |
9227 | return NULL; | |
9228 | return obj->maps + obj->nr_maps - 1; | |
9229 | } | |
9230 | ||
9231 | return __bpf_map__iter(next, obj, -1); | |
9232 | } | |
9233 | ||
561bbcca | 9234 | struct bpf_map * |
a324aae3 | 9235 | bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name) |
561bbcca WN |
9236 | { |
9237 | struct bpf_map *pos; | |
9238 | ||
f74a53d9 | 9239 | bpf_object__for_each_map(pos, obj) { |
973170e6 | 9240 | if (pos->name && !strcmp(pos->name, name)) |
561bbcca WN |
9241 | return pos; |
9242 | } | |
9243 | return NULL; | |
9244 | } | |
5a6acad1 | 9245 | |
f3cea32d | 9246 | int |
a324aae3 | 9247 | bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name) |
f3cea32d MF |
9248 | { |
9249 | return bpf_map__fd(bpf_object__find_map_by_name(obj, name)); | |
9250 | } | |
9251 | ||
5a6acad1 WN |
9252 | struct bpf_map * |
9253 | bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset) | |
9254 | { | |
db48814b | 9255 | return ERR_PTR(-ENOTSUP); |
5a6acad1 | 9256 | } |
e28ff1a8 JS |
9257 | |
9258 | long libbpf_get_error(const void *ptr) | |
9259 | { | |
d98363b5 | 9260 | return PTR_ERR_OR_ZERO(ptr); |
e28ff1a8 | 9261 | } |
6f6d33f3 JF |
9262 | |
9263 | int bpf_prog_load(const char *file, enum bpf_prog_type type, | |
9264 | struct bpf_object **pobj, int *prog_fd) | |
d7be143b AI |
9265 | { |
9266 | struct bpf_prog_load_attr attr; | |
9267 | ||
9268 | memset(&attr, 0, sizeof(struct bpf_prog_load_attr)); | |
9269 | attr.file = file; | |
9270 | attr.prog_type = type; | |
9271 | attr.expected_attach_type = 0; | |
9272 | ||
9273 | return bpf_prog_load_xattr(&attr, pobj, prog_fd); | |
9274 | } | |
9275 | ||
9276 | int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, | |
9277 | struct bpf_object **pobj, int *prog_fd) | |
6f6d33f3 | 9278 | { |
33bae185 | 9279 | struct bpf_object_open_attr open_attr = {}; |
48cca7e4 | 9280 | struct bpf_program *prog, *first_prog = NULL; |
6f6d33f3 | 9281 | struct bpf_object *obj; |
f0307a7e | 9282 | struct bpf_map *map; |
6f6d33f3 JF |
9283 | int err; |
9284 | ||
d7be143b AI |
9285 | if (!attr) |
9286 | return -EINVAL; | |
17387dd5 JK |
9287 | if (!attr->file) |
9288 | return -EINVAL; | |
d7be143b | 9289 | |
33bae185 LY |
9290 | open_attr.file = attr->file; |
9291 | open_attr.prog_type = attr->prog_type; | |
9292 | ||
07f2d4ea | 9293 | obj = bpf_object__open_xattr(&open_attr); |
3597683c | 9294 | if (IS_ERR_OR_NULL(obj)) |
6f6d33f3 JF |
9295 | return -ENOENT; |
9296 | ||
48cca7e4 | 9297 | bpf_object__for_each_program(prog, obj) { |
dd4436bb | 9298 | enum bpf_attach_type attach_type = attr->expected_attach_type; |
48cca7e4 | 9299 | /* |
dd4436bb AN |
9300 | * to preserve backwards compatibility, bpf_prog_load treats |
9301 | * attr->prog_type, if specified, as an override to whatever | |
9302 | * bpf_object__open guessed | |
48cca7e4 | 9303 | */ |
dd4436bb AN |
9304 | if (attr->prog_type != BPF_PROG_TYPE_UNSPEC) { |
9305 | bpf_program__set_type(prog, attr->prog_type); | |
9306 | bpf_program__set_expected_attach_type(prog, | |
9307 | attach_type); | |
9308 | } | |
9309 | if (bpf_program__get_type(prog) == BPF_PROG_TYPE_UNSPEC) { | |
9310 | /* | |
9311 | * we haven't guessed from section name and user | |
9312 | * didn't provide a fallback type, too bad... | |
9313 | */ | |
9314 | bpf_object__close(obj); | |
9315 | return -EINVAL; | |
583c9009 | 9316 | } |
48cca7e4 | 9317 | |
dd4436bb | 9318 | prog->prog_ifindex = attr->ifindex; |
da11b417 | 9319 | prog->log_level = attr->log_level; |
2b288740 | 9320 | prog->prog_flags |= attr->prog_flags; |
69495d2a | 9321 | if (!first_prog) |
48cca7e4 AS |
9322 | first_prog = prog; |
9323 | } | |
9324 | ||
f74a53d9 | 9325 | bpf_object__for_each_map(map, obj) { |
f83fb22c JK |
9326 | if (!bpf_map__is_offload_neutral(map)) |
9327 | map->map_ifindex = attr->ifindex; | |
f0307a7e DB |
9328 | } |
9329 | ||
48cca7e4 | 9330 | if (!first_prog) { |
be18010e | 9331 | pr_warn("object file doesn't contain bpf program\n"); |
48cca7e4 AS |
9332 | bpf_object__close(obj); |
9333 | return -ENOENT; | |
583c9009 RG |
9334 | } |
9335 | ||
6f6d33f3 JF |
9336 | err = bpf_object__load(obj); |
9337 | if (err) { | |
9338 | bpf_object__close(obj); | |
e411eb25 | 9339 | return err; |
6f6d33f3 JF |
9340 | } |
9341 | ||
9342 | *pobj = obj; | |
48cca7e4 | 9343 | *prog_fd = bpf_program__fd(first_prog); |
6f6d33f3 JF |
9344 | return 0; |
9345 | } | |
d0cabbb0 | 9346 | |
1c2e9efc | 9347 | struct bpf_link { |
d6958706 | 9348 | int (*detach)(struct bpf_link *link); |
1c2e9efc | 9349 | int (*destroy)(struct bpf_link *link); |
c016b68e AN |
9350 | char *pin_path; /* NULL, if not pinned */ |
9351 | int fd; /* hook FD, -1 if not applicable */ | |
d6958706 | 9352 | bool disconnected; |
1c2e9efc AN |
9353 | }; |
9354 | ||
cc4f864b AN |
9355 | /* Replace link's underlying BPF program with the new one */ |
9356 | int bpf_link__update_program(struct bpf_link *link, struct bpf_program *prog) | |
9357 | { | |
9358 | return bpf_link_update(bpf_link__fd(link), bpf_program__fd(prog), NULL); | |
9359 | } | |
9360 | ||
d6958706 AN |
9361 | /* Release "ownership" of underlying BPF resource (typically, BPF program |
9362 | * attached to some BPF hook, e.g., tracepoint, kprobe, etc). Disconnected | |
9363 | * link, when destructed through bpf_link__destroy() call won't attempt to | |
9364 | * detach/unregisted that BPF resource. This is useful in situations where, | |
9365 | * say, attached BPF program has to outlive userspace program that attached it | |
9366 | * in the system. Depending on type of BPF program, though, there might be | |
9367 | * additional steps (like pinning BPF program in BPF FS) necessary to ensure | |
9368 | * exit of userspace program doesn't trigger automatic detachment and clean up | |
9369 | * inside the kernel. | |
9370 | */ | |
9371 | void bpf_link__disconnect(struct bpf_link *link) | |
9372 | { | |
9373 | link->disconnected = true; | |
9374 | } | |
9375 | ||
1c2e9efc AN |
9376 | int bpf_link__destroy(struct bpf_link *link) |
9377 | { | |
d6958706 | 9378 | int err = 0; |
1c2e9efc | 9379 | |
50450fc7 | 9380 | if (IS_ERR_OR_NULL(link)) |
1c2e9efc AN |
9381 | return 0; |
9382 | ||
d6958706 AN |
9383 | if (!link->disconnected && link->detach) |
9384 | err = link->detach(link); | |
9385 | if (link->destroy) | |
9386 | link->destroy(link); | |
c016b68e AN |
9387 | if (link->pin_path) |
9388 | free(link->pin_path); | |
1c2e9efc AN |
9389 | free(link); |
9390 | ||
9391 | return err; | |
9392 | } | |
9393 | ||
c016b68e AN |
9394 | int bpf_link__fd(const struct bpf_link *link) |
9395 | { | |
9396 | return link->fd; | |
9397 | } | |
9398 | ||
9399 | const char *bpf_link__pin_path(const struct bpf_link *link) | |
9400 | { | |
9401 | return link->pin_path; | |
9402 | } | |
9403 | ||
9404 | static int bpf_link__detach_fd(struct bpf_link *link) | |
9405 | { | |
9406 | return close(link->fd); | |
9407 | } | |
9408 | ||
9409 | struct bpf_link *bpf_link__open(const char *path) | |
9410 | { | |
9411 | struct bpf_link *link; | |
9412 | int fd; | |
9413 | ||
9414 | fd = bpf_obj_get(path); | |
9415 | if (fd < 0) { | |
9416 | fd = -errno; | |
9417 | pr_warn("failed to open link at %s: %d\n", path, fd); | |
9418 | return ERR_PTR(fd); | |
9419 | } | |
9420 | ||
9421 | link = calloc(1, sizeof(*link)); | |
9422 | if (!link) { | |
9423 | close(fd); | |
9424 | return ERR_PTR(-ENOMEM); | |
9425 | } | |
9426 | link->detach = &bpf_link__detach_fd; | |
9427 | link->fd = fd; | |
9428 | ||
9429 | link->pin_path = strdup(path); | |
9430 | if (!link->pin_path) { | |
9431 | bpf_link__destroy(link); | |
9432 | return ERR_PTR(-ENOMEM); | |
9433 | } | |
9434 | ||
9435 | return link; | |
9436 | } | |
9437 | ||
2e49527e AN |
9438 | int bpf_link__detach(struct bpf_link *link) |
9439 | { | |
9440 | return bpf_link_detach(link->fd) ? -errno : 0; | |
9441 | } | |
9442 | ||
c016b68e AN |
9443 | int bpf_link__pin(struct bpf_link *link, const char *path) |
9444 | { | |
9445 | int err; | |
9446 | ||
9447 | if (link->pin_path) | |
9448 | return -EBUSY; | |
9449 | err = make_parent_dir(path); | |
9450 | if (err) | |
9451 | return err; | |
9452 | err = check_path(path); | |
9453 | if (err) | |
9454 | return err; | |
9455 | ||
9456 | link->pin_path = strdup(path); | |
9457 | if (!link->pin_path) | |
9458 | return -ENOMEM; | |
9459 | ||
9460 | if (bpf_obj_pin(link->fd, link->pin_path)) { | |
9461 | err = -errno; | |
9462 | zfree(&link->pin_path); | |
9463 | return err; | |
9464 | } | |
9465 | ||
9466 | pr_debug("link fd=%d: pinned at %s\n", link->fd, link->pin_path); | |
9467 | return 0; | |
9468 | } | |
9469 | ||
9470 | int bpf_link__unpin(struct bpf_link *link) | |
9471 | { | |
9472 | int err; | |
9473 | ||
9474 | if (!link->pin_path) | |
9475 | return -EINVAL; | |
9476 | ||
9477 | err = unlink(link->pin_path); | |
9478 | if (err != 0) | |
9479 | return -errno; | |
9480 | ||
9481 | pr_debug("link fd=%d: unpinned from %s\n", link->fd, link->pin_path); | |
9482 | zfree(&link->pin_path); | |
9483 | return 0; | |
9484 | } | |
63f2f5ee | 9485 | |
d6958706 | 9486 | static int bpf_link__detach_perf_event(struct bpf_link *link) |
63f2f5ee | 9487 | { |
63f2f5ee AN |
9488 | int err; |
9489 | ||
c016b68e | 9490 | err = ioctl(link->fd, PERF_EVENT_IOC_DISABLE, 0); |
63f2f5ee AN |
9491 | if (err) |
9492 | err = -errno; | |
9493 | ||
c016b68e | 9494 | close(link->fd); |
63f2f5ee AN |
9495 | return err; |
9496 | } | |
9497 | ||
9498 | struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog, | |
9499 | int pfd) | |
9500 | { | |
9501 | char errmsg[STRERR_BUFSIZE]; | |
c016b68e | 9502 | struct bpf_link *link; |
63f2f5ee AN |
9503 | int prog_fd, err; |
9504 | ||
9505 | if (pfd < 0) { | |
52109584 AN |
9506 | pr_warn("prog '%s': invalid perf event FD %d\n", |
9507 | prog->name, pfd); | |
63f2f5ee AN |
9508 | return ERR_PTR(-EINVAL); |
9509 | } | |
9510 | prog_fd = bpf_program__fd(prog); | |
9511 | if (prog_fd < 0) { | |
52109584 AN |
9512 | pr_warn("prog '%s': can't attach BPF program w/o FD (did you load it?)\n", |
9513 | prog->name); | |
63f2f5ee AN |
9514 | return ERR_PTR(-EINVAL); |
9515 | } | |
9516 | ||
d6958706 | 9517 | link = calloc(1, sizeof(*link)); |
63f2f5ee AN |
9518 | if (!link) |
9519 | return ERR_PTR(-ENOMEM); | |
c016b68e | 9520 | link->detach = &bpf_link__detach_perf_event; |
63f2f5ee AN |
9521 | link->fd = pfd; |
9522 | ||
9523 | if (ioctl(pfd, PERF_EVENT_IOC_SET_BPF, prog_fd) < 0) { | |
9524 | err = -errno; | |
9525 | free(link); | |
52109584 AN |
9526 | pr_warn("prog '%s': failed to attach to pfd %d: %s\n", |
9527 | prog->name, pfd, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
d4b4dd6c | 9528 | if (err == -EPROTO) |
52109584 AN |
9529 | pr_warn("prog '%s': try add PERF_SAMPLE_CALLCHAIN to or remove exclude_callchain_[kernel|user] from pfd %d\n", |
9530 | prog->name, pfd); | |
63f2f5ee AN |
9531 | return ERR_PTR(err); |
9532 | } | |
9533 | if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) { | |
9534 | err = -errno; | |
9535 | free(link); | |
52109584 AN |
9536 | pr_warn("prog '%s': failed to enable pfd %d: %s\n", |
9537 | prog->name, pfd, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
63f2f5ee AN |
9538 | return ERR_PTR(err); |
9539 | } | |
c016b68e | 9540 | return link; |
63f2f5ee AN |
9541 | } |
9542 | ||
b2650027 AN |
9543 | /* |
9544 | * this function is expected to parse integer in the range of [0, 2^31-1] from | |
9545 | * given file using scanf format string fmt. If actual parsed value is | |
9546 | * negative, the result might be indistinguishable from error | |
9547 | */ | |
9548 | static int parse_uint_from_file(const char *file, const char *fmt) | |
9549 | { | |
9550 | char buf[STRERR_BUFSIZE]; | |
9551 | int err, ret; | |
9552 | FILE *f; | |
9553 | ||
9554 | f = fopen(file, "r"); | |
9555 | if (!f) { | |
9556 | err = -errno; | |
9557 | pr_debug("failed to open '%s': %s\n", file, | |
9558 | libbpf_strerror_r(err, buf, sizeof(buf))); | |
9559 | return err; | |
9560 | } | |
9561 | err = fscanf(f, fmt, &ret); | |
9562 | if (err != 1) { | |
9563 | err = err == EOF ? -EIO : -errno; | |
9564 | pr_debug("failed to parse '%s': %s\n", file, | |
9565 | libbpf_strerror_r(err, buf, sizeof(buf))); | |
9566 | fclose(f); | |
9567 | return err; | |
9568 | } | |
9569 | fclose(f); | |
9570 | return ret; | |
9571 | } | |
9572 | ||
9573 | static int determine_kprobe_perf_type(void) | |
9574 | { | |
9575 | const char *file = "/sys/bus/event_source/devices/kprobe/type"; | |
9576 | ||
9577 | return parse_uint_from_file(file, "%d\n"); | |
9578 | } | |
9579 | ||
9580 | static int determine_uprobe_perf_type(void) | |
9581 | { | |
9582 | const char *file = "/sys/bus/event_source/devices/uprobe/type"; | |
9583 | ||
9584 | return parse_uint_from_file(file, "%d\n"); | |
9585 | } | |
9586 | ||
9587 | static int determine_kprobe_retprobe_bit(void) | |
9588 | { | |
9589 | const char *file = "/sys/bus/event_source/devices/kprobe/format/retprobe"; | |
9590 | ||
9591 | return parse_uint_from_file(file, "config:%d\n"); | |
9592 | } | |
9593 | ||
9594 | static int determine_uprobe_retprobe_bit(void) | |
9595 | { | |
9596 | const char *file = "/sys/bus/event_source/devices/uprobe/format/retprobe"; | |
9597 | ||
9598 | return parse_uint_from_file(file, "config:%d\n"); | |
9599 | } | |
9600 | ||
9601 | static int perf_event_open_probe(bool uprobe, bool retprobe, const char *name, | |
9602 | uint64_t offset, int pid) | |
9603 | { | |
9604 | struct perf_event_attr attr = {}; | |
9605 | char errmsg[STRERR_BUFSIZE]; | |
9606 | int type, pfd, err; | |
9607 | ||
9608 | type = uprobe ? determine_uprobe_perf_type() | |
9609 | : determine_kprobe_perf_type(); | |
9610 | if (type < 0) { | |
be18010e KW |
9611 | pr_warn("failed to determine %s perf type: %s\n", |
9612 | uprobe ? "uprobe" : "kprobe", | |
9613 | libbpf_strerror_r(type, errmsg, sizeof(errmsg))); | |
b2650027 AN |
9614 | return type; |
9615 | } | |
9616 | if (retprobe) { | |
9617 | int bit = uprobe ? determine_uprobe_retprobe_bit() | |
9618 | : determine_kprobe_retprobe_bit(); | |
9619 | ||
9620 | if (bit < 0) { | |
be18010e KW |
9621 | pr_warn("failed to determine %s retprobe bit: %s\n", |
9622 | uprobe ? "uprobe" : "kprobe", | |
9623 | libbpf_strerror_r(bit, errmsg, sizeof(errmsg))); | |
b2650027 AN |
9624 | return bit; |
9625 | } | |
9626 | attr.config |= 1 << bit; | |
9627 | } | |
9628 | attr.size = sizeof(attr); | |
9629 | attr.type = type; | |
36db2a94 AN |
9630 | attr.config1 = ptr_to_u64(name); /* kprobe_func or uprobe_path */ |
9631 | attr.config2 = offset; /* kprobe_addr or probe_offset */ | |
b2650027 AN |
9632 | |
9633 | /* pid filter is meaningful only for uprobes */ | |
9634 | pfd = syscall(__NR_perf_event_open, &attr, | |
9635 | pid < 0 ? -1 : pid /* pid */, | |
9636 | pid == -1 ? 0 : -1 /* cpu */, | |
9637 | -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); | |
9638 | if (pfd < 0) { | |
9639 | err = -errno; | |
be18010e KW |
9640 | pr_warn("%s perf_event_open() failed: %s\n", |
9641 | uprobe ? "uprobe" : "kprobe", | |
9642 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
b2650027 AN |
9643 | return err; |
9644 | } | |
9645 | return pfd; | |
9646 | } | |
9647 | ||
9648 | struct bpf_link *bpf_program__attach_kprobe(struct bpf_program *prog, | |
9649 | bool retprobe, | |
9650 | const char *func_name) | |
9651 | { | |
9652 | char errmsg[STRERR_BUFSIZE]; | |
9653 | struct bpf_link *link; | |
9654 | int pfd, err; | |
9655 | ||
9656 | pfd = perf_event_open_probe(false /* uprobe */, retprobe, func_name, | |
9657 | 0 /* offset */, -1 /* pid */); | |
9658 | if (pfd < 0) { | |
52109584 AN |
9659 | pr_warn("prog '%s': failed to create %s '%s' perf event: %s\n", |
9660 | prog->name, retprobe ? "kretprobe" : "kprobe", func_name, | |
be18010e | 9661 | libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
b2650027 AN |
9662 | return ERR_PTR(pfd); |
9663 | } | |
9664 | link = bpf_program__attach_perf_event(prog, pfd); | |
9665 | if (IS_ERR(link)) { | |
9666 | close(pfd); | |
9667 | err = PTR_ERR(link); | |
52109584 AN |
9668 | pr_warn("prog '%s': failed to attach to %s '%s': %s\n", |
9669 | prog->name, retprobe ? "kretprobe" : "kprobe", func_name, | |
be18010e | 9670 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
b2650027 AN |
9671 | return link; |
9672 | } | |
9673 | return link; | |
9674 | } | |
9675 | ||
d7a18ea7 AN |
9676 | static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec, |
9677 | struct bpf_program *prog) | |
9678 | { | |
9679 | const char *func_name; | |
9680 | bool retprobe; | |
9681 | ||
52109584 | 9682 | func_name = prog->sec_name + sec->len; |
d7a18ea7 AN |
9683 | retprobe = strcmp(sec->sec, "kretprobe/") == 0; |
9684 | ||
9685 | return bpf_program__attach_kprobe(prog, retprobe, func_name); | |
9686 | } | |
9687 | ||
b2650027 AN |
9688 | struct bpf_link *bpf_program__attach_uprobe(struct bpf_program *prog, |
9689 | bool retprobe, pid_t pid, | |
9690 | const char *binary_path, | |
9691 | size_t func_offset) | |
9692 | { | |
9693 | char errmsg[STRERR_BUFSIZE]; | |
9694 | struct bpf_link *link; | |
9695 | int pfd, err; | |
9696 | ||
9697 | pfd = perf_event_open_probe(true /* uprobe */, retprobe, | |
9698 | binary_path, func_offset, pid); | |
9699 | if (pfd < 0) { | |
52109584 AN |
9700 | pr_warn("prog '%s': failed to create %s '%s:0x%zx' perf event: %s\n", |
9701 | prog->name, retprobe ? "uretprobe" : "uprobe", | |
be18010e KW |
9702 | binary_path, func_offset, |
9703 | libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); | |
b2650027 AN |
9704 | return ERR_PTR(pfd); |
9705 | } | |
9706 | link = bpf_program__attach_perf_event(prog, pfd); | |
9707 | if (IS_ERR(link)) { | |
9708 | close(pfd); | |
9709 | err = PTR_ERR(link); | |
52109584 AN |
9710 | pr_warn("prog '%s': failed to attach to %s '%s:0x%zx': %s\n", |
9711 | prog->name, retprobe ? "uretprobe" : "uprobe", | |
be18010e KW |
9712 | binary_path, func_offset, |
9713 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
b2650027 AN |
9714 | return link; |
9715 | } | |
9716 | return link; | |
9717 | } | |
9718 | ||
f6de59c1 AN |
9719 | static int determine_tracepoint_id(const char *tp_category, |
9720 | const char *tp_name) | |
9721 | { | |
9722 | char file[PATH_MAX]; | |
9723 | int ret; | |
9724 | ||
9725 | ret = snprintf(file, sizeof(file), | |
9726 | "/sys/kernel/debug/tracing/events/%s/%s/id", | |
9727 | tp_category, tp_name); | |
9728 | if (ret < 0) | |
9729 | return -errno; | |
9730 | if (ret >= sizeof(file)) { | |
9731 | pr_debug("tracepoint %s/%s path is too long\n", | |
9732 | tp_category, tp_name); | |
9733 | return -E2BIG; | |
9734 | } | |
9735 | return parse_uint_from_file(file, "%d\n"); | |
9736 | } | |
9737 | ||
9738 | static int perf_event_open_tracepoint(const char *tp_category, | |
9739 | const char *tp_name) | |
9740 | { | |
9741 | struct perf_event_attr attr = {}; | |
9742 | char errmsg[STRERR_BUFSIZE]; | |
9743 | int tp_id, pfd, err; | |
9744 | ||
9745 | tp_id = determine_tracepoint_id(tp_category, tp_name); | |
9746 | if (tp_id < 0) { | |
be18010e KW |
9747 | pr_warn("failed to determine tracepoint '%s/%s' perf event ID: %s\n", |
9748 | tp_category, tp_name, | |
9749 | libbpf_strerror_r(tp_id, errmsg, sizeof(errmsg))); | |
f6de59c1 AN |
9750 | return tp_id; |
9751 | } | |
9752 | ||
9753 | attr.type = PERF_TYPE_TRACEPOINT; | |
9754 | attr.size = sizeof(attr); | |
9755 | attr.config = tp_id; | |
9756 | ||
9757 | pfd = syscall(__NR_perf_event_open, &attr, -1 /* pid */, 0 /* cpu */, | |
9758 | -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); | |
9759 | if (pfd < 0) { | |
9760 | err = -errno; | |
be18010e KW |
9761 | pr_warn("tracepoint '%s/%s' perf_event_open() failed: %s\n", |
9762 | tp_category, tp_name, | |
9763 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); | |
f6de59c1 AN |
9764 | return err; |
9765 | } | |
9766 | return pfd; | |
9767 | } | |
9768 | ||
9769 | struct bpf_link *bpf_program__attach_tracepoint(struct bpf_program *prog, | |
9770 | const char *tp_category, | |
9771 | const char *tp_name) | |
9772 | { | |
9773 | char errmsg[STRERR_BUFSIZE]; | |
9774 | struct bpf_link *link; | |
9775 | int pfd, err; | |
9776 | ||
9777 | pfd = perf_event_open_tracepoint(tp_category, tp_name); | |
9778 | if (pfd < 0) { | |
52109584 AN |
9779 | pr_warn("prog '%s': failed to create tracepoint '%s/%s' perf event: %s\n", |
9780 | prog->name, tp_category, tp_name, | |
be18010e | 9781 | libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
f6de59c1 AN |
9782 | return ERR_PTR(pfd); |
9783 | } | |
9784 | link = bpf_program__attach_perf_event(prog, pfd); | |
9785 | if (IS_ERR(link)) { | |
9786 | close(pfd); | |
9787 | err = PTR_ERR(link); | |
52109584 AN |
9788 | pr_warn("prog '%s': failed to attach to tracepoint '%s/%s': %s\n", |
9789 | prog->name, tp_category, tp_name, | |
be18010e | 9790 | libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
f6de59c1 AN |
9791 | return link; |
9792 | } | |
9793 | return link; | |
9794 | } | |
9795 | ||
d7a18ea7 AN |
9796 | static struct bpf_link *attach_tp(const struct bpf_sec_def *sec, |
9797 | struct bpf_program *prog) | |
9798 | { | |
9799 | char *sec_name, *tp_cat, *tp_name; | |
9800 | struct bpf_link *link; | |
9801 | ||
52109584 | 9802 | sec_name = strdup(prog->sec_name); |
d7a18ea7 AN |
9803 | if (!sec_name) |
9804 | return ERR_PTR(-ENOMEM); | |
9805 | ||
9806 | /* extract "tp/<category>/<name>" */ | |
9807 | tp_cat = sec_name + sec->len; | |
9808 | tp_name = strchr(tp_cat, '/'); | |
9809 | if (!tp_name) { | |
9810 | link = ERR_PTR(-EINVAL); | |
9811 | goto out; | |
9812 | } | |
9813 | *tp_name = '\0'; | |
9814 | tp_name++; | |
9815 | ||
9816 | link = bpf_program__attach_tracepoint(prog, tp_cat, tp_name); | |
9817 | out: | |
9818 | free(sec_name); | |
9819 | return link; | |
9820 | } | |
9821 | ||
84bf5e1f AN |
9822 | struct bpf_link *bpf_program__attach_raw_tracepoint(struct bpf_program *prog, |
9823 | const char *tp_name) | |
9824 | { | |
9825 | char errmsg[STRERR_BUFSIZE]; | |
c016b68e | 9826 | struct bpf_link *link; |
84bf5e1f AN |
9827 | int prog_fd, pfd; |
9828 | ||
9829 | prog_fd = bpf_program__fd(prog); | |
9830 | if (prog_fd < 0) { | |
52109584 | 9831 | pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
84bf5e1f AN |
9832 | return ERR_PTR(-EINVAL); |
9833 | } | |
9834 | ||
d6958706 | 9835 | link = calloc(1, sizeof(*link)); |
84bf5e1f AN |
9836 | if (!link) |
9837 | return ERR_PTR(-ENOMEM); | |
c016b68e | 9838 | link->detach = &bpf_link__detach_fd; |
84bf5e1f AN |
9839 | |
9840 | pfd = bpf_raw_tracepoint_open(tp_name, prog_fd); | |
9841 | if (pfd < 0) { | |
9842 | pfd = -errno; | |
9843 | free(link); | |
52109584 AN |
9844 | pr_warn("prog '%s': failed to attach to raw tracepoint '%s': %s\n", |
9845 | prog->name, tp_name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); | |
84bf5e1f AN |
9846 | return ERR_PTR(pfd); |
9847 | } | |
9848 | link->fd = pfd; | |
c016b68e | 9849 | return link; |
84bf5e1f AN |
9850 | } |
9851 | ||
d7a18ea7 AN |
9852 | static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec, |
9853 | struct bpf_program *prog) | |
9854 | { | |
52109584 | 9855 | const char *tp_name = prog->sec_name + sec->len; |
d7a18ea7 AN |
9856 | |
9857 | return bpf_program__attach_raw_tracepoint(prog, tp_name); | |
9858 | } | |
9859 | ||
1e092a03 KS |
9860 | /* Common logic for all BPF program types that attach to a btf_id */ |
9861 | static struct bpf_link *bpf_program__attach_btf_id(struct bpf_program *prog) | |
b8c54ea4 AS |
9862 | { |
9863 | char errmsg[STRERR_BUFSIZE]; | |
c016b68e | 9864 | struct bpf_link *link; |
b8c54ea4 AS |
9865 | int prog_fd, pfd; |
9866 | ||
9867 | prog_fd = bpf_program__fd(prog); | |
9868 | if (prog_fd < 0) { | |
52109584 | 9869 | pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
b8c54ea4 AS |
9870 | return ERR_PTR(-EINVAL); |
9871 | } | |
9872 | ||
d6958706 | 9873 | link = calloc(1, sizeof(*link)); |
b8c54ea4 AS |
9874 | if (!link) |
9875 | return ERR_PTR(-ENOMEM); | |
c016b68e | 9876 | link->detach = &bpf_link__detach_fd; |
b8c54ea4 AS |
9877 | |
9878 | pfd = bpf_raw_tracepoint_open(NULL, prog_fd); | |
9879 | if (pfd < 0) { | |
9880 | pfd = -errno; | |
9881 | free(link); | |
52109584 AN |
9882 | pr_warn("prog '%s': failed to attach: %s\n", |
9883 | prog->name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); | |
b8c54ea4 AS |
9884 | return ERR_PTR(pfd); |
9885 | } | |
9886 | link->fd = pfd; | |
9887 | return (struct bpf_link *)link; | |
9888 | } | |
9889 | ||
1e092a03 KS |
9890 | struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog) |
9891 | { | |
9892 | return bpf_program__attach_btf_id(prog); | |
9893 | } | |
9894 | ||
9895 | struct bpf_link *bpf_program__attach_lsm(struct bpf_program *prog) | |
9896 | { | |
9897 | return bpf_program__attach_btf_id(prog); | |
9898 | } | |
9899 | ||
d7a18ea7 AN |
9900 | static struct bpf_link *attach_trace(const struct bpf_sec_def *sec, |
9901 | struct bpf_program *prog) | |
9902 | { | |
9903 | return bpf_program__attach_trace(prog); | |
9904 | } | |
9905 | ||
1e092a03 KS |
9906 | static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec, |
9907 | struct bpf_program *prog) | |
9908 | { | |
9909 | return bpf_program__attach_lsm(prog); | |
9910 | } | |
9911 | ||
c09add2f YS |
9912 | static struct bpf_link *attach_iter(const struct bpf_sec_def *sec, |
9913 | struct bpf_program *prog) | |
9914 | { | |
9915 | return bpf_program__attach_iter(prog, NULL); | |
9916 | } | |
9917 | ||
d60d81ac | 9918 | static struct bpf_link * |
a5359091 | 9919 | bpf_program__attach_fd(struct bpf_program *prog, int target_fd, int btf_id, |
d60d81ac | 9920 | const char *target_name) |
cc4f864b | 9921 | { |
a5359091 THJ |
9922 | DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts, |
9923 | .target_btf_id = btf_id); | |
cc4f864b AN |
9924 | enum bpf_attach_type attach_type; |
9925 | char errmsg[STRERR_BUFSIZE]; | |
9926 | struct bpf_link *link; | |
9927 | int prog_fd, link_fd; | |
9928 | ||
9929 | prog_fd = bpf_program__fd(prog); | |
9930 | if (prog_fd < 0) { | |
52109584 | 9931 | pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
cc4f864b AN |
9932 | return ERR_PTR(-EINVAL); |
9933 | } | |
9934 | ||
9935 | link = calloc(1, sizeof(*link)); | |
9936 | if (!link) | |
9937 | return ERR_PTR(-ENOMEM); | |
9938 | link->detach = &bpf_link__detach_fd; | |
9939 | ||
9940 | attach_type = bpf_program__get_expected_attach_type(prog); | |
a5359091 | 9941 | link_fd = bpf_link_create(prog_fd, target_fd, attach_type, &opts); |
cc4f864b AN |
9942 | if (link_fd < 0) { |
9943 | link_fd = -errno; | |
9944 | free(link); | |
52109584 AN |
9945 | pr_warn("prog '%s': failed to attach to %s: %s\n", |
9946 | prog->name, target_name, | |
cc4f864b AN |
9947 | libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg))); |
9948 | return ERR_PTR(link_fd); | |
9949 | } | |
9950 | link->fd = link_fd; | |
9951 | return link; | |
9952 | } | |
9953 | ||
d60d81ac JS |
9954 | struct bpf_link * |
9955 | bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd) | |
9956 | { | |
a5359091 | 9957 | return bpf_program__attach_fd(prog, cgroup_fd, 0, "cgroup"); |
d60d81ac JS |
9958 | } |
9959 | ||
9960 | struct bpf_link * | |
9961 | bpf_program__attach_netns(struct bpf_program *prog, int netns_fd) | |
9962 | { | |
a5359091 | 9963 | return bpf_program__attach_fd(prog, netns_fd, 0, "netns"); |
d60d81ac JS |
9964 | } |
9965 | ||
dc8698ca AN |
9966 | struct bpf_link *bpf_program__attach_xdp(struct bpf_program *prog, int ifindex) |
9967 | { | |
9968 | /* target_fd/target_ifindex use the same field in LINK_CREATE */ | |
a5359091 THJ |
9969 | return bpf_program__attach_fd(prog, ifindex, 0, "xdp"); |
9970 | } | |
9971 | ||
9972 | struct bpf_link *bpf_program__attach_freplace(struct bpf_program *prog, | |
9973 | int target_fd, | |
9974 | const char *attach_func_name) | |
9975 | { | |
9976 | int btf_id; | |
9977 | ||
9978 | if (!!target_fd != !!attach_func_name) { | |
9979 | pr_warn("prog '%s': supply none or both of target_fd and attach_func_name\n", | |
9980 | prog->name); | |
9981 | return ERR_PTR(-EINVAL); | |
9982 | } | |
9983 | ||
9984 | if (prog->type != BPF_PROG_TYPE_EXT) { | |
9985 | pr_warn("prog '%s': only BPF_PROG_TYPE_EXT can attach as freplace", | |
9986 | prog->name); | |
9987 | return ERR_PTR(-EINVAL); | |
9988 | } | |
9989 | ||
9990 | if (target_fd) { | |
9991 | btf_id = libbpf_find_prog_btf_id(attach_func_name, target_fd); | |
9992 | if (btf_id < 0) | |
9993 | return ERR_PTR(btf_id); | |
9994 | ||
9995 | return bpf_program__attach_fd(prog, target_fd, btf_id, "freplace"); | |
9996 | } else { | |
9997 | /* no target, so use raw_tracepoint_open for compatibility | |
9998 | * with old kernels | |
9999 | */ | |
10000 | return bpf_program__attach_trace(prog); | |
10001 | } | |
dc8698ca AN |
10002 | } |
10003 | ||
c09add2f YS |
10004 | struct bpf_link * |
10005 | bpf_program__attach_iter(struct bpf_program *prog, | |
10006 | const struct bpf_iter_attach_opts *opts) | |
10007 | { | |
cd31039a | 10008 | DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_create_opts); |
c09add2f YS |
10009 | char errmsg[STRERR_BUFSIZE]; |
10010 | struct bpf_link *link; | |
10011 | int prog_fd, link_fd; | |
cd31039a | 10012 | __u32 target_fd = 0; |
c09add2f YS |
10013 | |
10014 | if (!OPTS_VALID(opts, bpf_iter_attach_opts)) | |
10015 | return ERR_PTR(-EINVAL); | |
10016 | ||
74fc097d YS |
10017 | link_create_opts.iter_info = OPTS_GET(opts, link_info, (void *)0); |
10018 | link_create_opts.iter_info_len = OPTS_GET(opts, link_info_len, 0); | |
cd31039a | 10019 | |
c09add2f YS |
10020 | prog_fd = bpf_program__fd(prog); |
10021 | if (prog_fd < 0) { | |
52109584 | 10022 | pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
c09add2f YS |
10023 | return ERR_PTR(-EINVAL); |
10024 | } | |
10025 | ||
10026 | link = calloc(1, sizeof(*link)); | |
10027 | if (!link) | |
10028 | return ERR_PTR(-ENOMEM); | |
10029 | link->detach = &bpf_link__detach_fd; | |
10030 | ||
cd31039a YS |
10031 | link_fd = bpf_link_create(prog_fd, target_fd, BPF_TRACE_ITER, |
10032 | &link_create_opts); | |
c09add2f YS |
10033 | if (link_fd < 0) { |
10034 | link_fd = -errno; | |
10035 | free(link); | |
52109584 AN |
10036 | pr_warn("prog '%s': failed to attach to iterator: %s\n", |
10037 | prog->name, libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg))); | |
c09add2f YS |
10038 | return ERR_PTR(link_fd); |
10039 | } | |
10040 | link->fd = link_fd; | |
10041 | return link; | |
10042 | } | |
10043 | ||
d7a18ea7 AN |
10044 | struct bpf_link *bpf_program__attach(struct bpf_program *prog) |
10045 | { | |
10046 | const struct bpf_sec_def *sec_def; | |
10047 | ||
52109584 | 10048 | sec_def = find_sec_def(prog->sec_name); |
d7a18ea7 AN |
10049 | if (!sec_def || !sec_def->attach_fn) |
10050 | return ERR_PTR(-ESRCH); | |
10051 | ||
10052 | return sec_def->attach_fn(sec_def, prog); | |
10053 | } | |
10054 | ||
590a0088 MKL |
10055 | static int bpf_link__detach_struct_ops(struct bpf_link *link) |
10056 | { | |
590a0088 MKL |
10057 | __u32 zero = 0; |
10058 | ||
c016b68e | 10059 | if (bpf_map_delete_elem(link->fd, &zero)) |
590a0088 MKL |
10060 | return -errno; |
10061 | ||
10062 | return 0; | |
10063 | } | |
10064 | ||
10065 | struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map) | |
10066 | { | |
10067 | struct bpf_struct_ops *st_ops; | |
c016b68e | 10068 | struct bpf_link *link; |
590a0088 MKL |
10069 | __u32 i, zero = 0; |
10070 | int err; | |
10071 | ||
10072 | if (!bpf_map__is_struct_ops(map) || map->fd == -1) | |
10073 | return ERR_PTR(-EINVAL); | |
10074 | ||
10075 | link = calloc(1, sizeof(*link)); | |
10076 | if (!link) | |
10077 | return ERR_PTR(-EINVAL); | |
10078 | ||
10079 | st_ops = map->st_ops; | |
10080 | for (i = 0; i < btf_vlen(st_ops->type); i++) { | |
10081 | struct bpf_program *prog = st_ops->progs[i]; | |
10082 | void *kern_data; | |
10083 | int prog_fd; | |
10084 | ||
10085 | if (!prog) | |
10086 | continue; | |
10087 | ||
10088 | prog_fd = bpf_program__fd(prog); | |
10089 | kern_data = st_ops->kern_vdata + st_ops->kern_func_off[i]; | |
10090 | *(unsigned long *)kern_data = prog_fd; | |
10091 | } | |
10092 | ||
10093 | err = bpf_map_update_elem(map->fd, &zero, st_ops->kern_vdata, 0); | |
10094 | if (err) { | |
10095 | err = -errno; | |
10096 | free(link); | |
10097 | return ERR_PTR(err); | |
10098 | } | |
10099 | ||
c016b68e | 10100 | link->detach = bpf_link__detach_struct_ops; |
590a0088 MKL |
10101 | link->fd = map->fd; |
10102 | ||
c016b68e | 10103 | return link; |
590a0088 MKL |
10104 | } |
10105 | ||
d0cabbb0 | 10106 | enum bpf_perf_event_ret |
3dca2115 DB |
10107 | bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size, |
10108 | void **copy_mem, size_t *copy_size, | |
10109 | bpf_perf_event_print_t fn, void *private_data) | |
d0cabbb0 | 10110 | { |
3dca2115 | 10111 | struct perf_event_mmap_page *header = mmap_mem; |
a64af0ef | 10112 | __u64 data_head = ring_buffer_read_head(header); |
d0cabbb0 | 10113 | __u64 data_tail = header->data_tail; |
3dca2115 DB |
10114 | void *base = ((__u8 *)header) + page_size; |
10115 | int ret = LIBBPF_PERF_EVENT_CONT; | |
10116 | struct perf_event_header *ehdr; | |
10117 | size_t ehdr_size; | |
10118 | ||
10119 | while (data_head != data_tail) { | |
10120 | ehdr = base + (data_tail & (mmap_size - 1)); | |
10121 | ehdr_size = ehdr->size; | |
10122 | ||
10123 | if (((void *)ehdr) + ehdr_size > base + mmap_size) { | |
10124 | void *copy_start = ehdr; | |
10125 | size_t len_first = base + mmap_size - copy_start; | |
10126 | size_t len_secnd = ehdr_size - len_first; | |
10127 | ||
10128 | if (*copy_size < ehdr_size) { | |
10129 | free(*copy_mem); | |
10130 | *copy_mem = malloc(ehdr_size); | |
10131 | if (!*copy_mem) { | |
10132 | *copy_size = 0; | |
d0cabbb0 JK |
10133 | ret = LIBBPF_PERF_EVENT_ERROR; |
10134 | break; | |
10135 | } | |
3dca2115 | 10136 | *copy_size = ehdr_size; |
d0cabbb0 JK |
10137 | } |
10138 | ||
3dca2115 DB |
10139 | memcpy(*copy_mem, copy_start, len_first); |
10140 | memcpy(*copy_mem + len_first, base, len_secnd); | |
10141 | ehdr = *copy_mem; | |
d0cabbb0 JK |
10142 | } |
10143 | ||
3dca2115 DB |
10144 | ret = fn(ehdr, private_data); |
10145 | data_tail += ehdr_size; | |
d0cabbb0 JK |
10146 | if (ret != LIBBPF_PERF_EVENT_CONT) |
10147 | break; | |
d0cabbb0 JK |
10148 | } |
10149 | ||
a64af0ef | 10150 | ring_buffer_write_tail(header, data_tail); |
d0cabbb0 JK |
10151 | return ret; |
10152 | } | |
34be1646 | 10153 | |
fb84b822 AN |
10154 | struct perf_buffer; |
10155 | ||
10156 | struct perf_buffer_params { | |
10157 | struct perf_event_attr *attr; | |
10158 | /* if event_cb is specified, it takes precendence */ | |
10159 | perf_buffer_event_fn event_cb; | |
10160 | /* sample_cb and lost_cb are higher-level common-case callbacks */ | |
10161 | perf_buffer_sample_fn sample_cb; | |
10162 | perf_buffer_lost_fn lost_cb; | |
10163 | void *ctx; | |
10164 | int cpu_cnt; | |
10165 | int *cpus; | |
10166 | int *map_keys; | |
10167 | }; | |
10168 | ||
10169 | struct perf_cpu_buf { | |
10170 | struct perf_buffer *pb; | |
10171 | void *base; /* mmap()'ed memory */ | |
10172 | void *buf; /* for reconstructing segmented data */ | |
10173 | size_t buf_size; | |
10174 | int fd; | |
10175 | int cpu; | |
10176 | int map_key; | |
10177 | }; | |
10178 | ||
10179 | struct perf_buffer { | |
10180 | perf_buffer_event_fn event_cb; | |
10181 | perf_buffer_sample_fn sample_cb; | |
10182 | perf_buffer_lost_fn lost_cb; | |
10183 | void *ctx; /* passed into callbacks */ | |
10184 | ||
10185 | size_t page_size; | |
10186 | size_t mmap_size; | |
10187 | struct perf_cpu_buf **cpu_bufs; | |
10188 | struct epoll_event *events; | |
783b8f01 | 10189 | int cpu_cnt; /* number of allocated CPU buffers */ |
fb84b822 AN |
10190 | int epoll_fd; /* perf event FD */ |
10191 | int map_fd; /* BPF_MAP_TYPE_PERF_EVENT_ARRAY BPF map FD */ | |
10192 | }; | |
10193 | ||
10194 | static void perf_buffer__free_cpu_buf(struct perf_buffer *pb, | |
10195 | struct perf_cpu_buf *cpu_buf) | |
10196 | { | |
10197 | if (!cpu_buf) | |
10198 | return; | |
10199 | if (cpu_buf->base && | |
10200 | munmap(cpu_buf->base, pb->mmap_size + pb->page_size)) | |
be18010e | 10201 | pr_warn("failed to munmap cpu_buf #%d\n", cpu_buf->cpu); |
fb84b822 AN |
10202 | if (cpu_buf->fd >= 0) { |
10203 | ioctl(cpu_buf->fd, PERF_EVENT_IOC_DISABLE, 0); | |
10204 | close(cpu_buf->fd); | |
10205 | } | |
10206 | free(cpu_buf->buf); | |
10207 | free(cpu_buf); | |
10208 | } | |
10209 | ||
10210 | void perf_buffer__free(struct perf_buffer *pb) | |
10211 | { | |
10212 | int i; | |
10213 | ||
50450fc7 | 10214 | if (IS_ERR_OR_NULL(pb)) |
fb84b822 AN |
10215 | return; |
10216 | if (pb->cpu_bufs) { | |
601b05ca | 10217 | for (i = 0; i < pb->cpu_cnt; i++) { |
fb84b822 AN |
10218 | struct perf_cpu_buf *cpu_buf = pb->cpu_bufs[i]; |
10219 | ||
601b05ca EC |
10220 | if (!cpu_buf) |
10221 | continue; | |
10222 | ||
fb84b822 AN |
10223 | bpf_map_delete_elem(pb->map_fd, &cpu_buf->map_key); |
10224 | perf_buffer__free_cpu_buf(pb, cpu_buf); | |
10225 | } | |
10226 | free(pb->cpu_bufs); | |
10227 | } | |
10228 | if (pb->epoll_fd >= 0) | |
10229 | close(pb->epoll_fd); | |
10230 | free(pb->events); | |
10231 | free(pb); | |
10232 | } | |
10233 | ||
10234 | static struct perf_cpu_buf * | |
10235 | perf_buffer__open_cpu_buf(struct perf_buffer *pb, struct perf_event_attr *attr, | |
10236 | int cpu, int map_key) | |
10237 | { | |
10238 | struct perf_cpu_buf *cpu_buf; | |
10239 | char msg[STRERR_BUFSIZE]; | |
10240 | int err; | |
10241 | ||
10242 | cpu_buf = calloc(1, sizeof(*cpu_buf)); | |
10243 | if (!cpu_buf) | |
10244 | return ERR_PTR(-ENOMEM); | |
10245 | ||
10246 | cpu_buf->pb = pb; | |
10247 | cpu_buf->cpu = cpu; | |
10248 | cpu_buf->map_key = map_key; | |
10249 | ||
10250 | cpu_buf->fd = syscall(__NR_perf_event_open, attr, -1 /* pid */, cpu, | |
10251 | -1, PERF_FLAG_FD_CLOEXEC); | |
10252 | if (cpu_buf->fd < 0) { | |
10253 | err = -errno; | |
be18010e KW |
10254 | pr_warn("failed to open perf buffer event on cpu #%d: %s\n", |
10255 | cpu, libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
10256 | goto error; |
10257 | } | |
10258 | ||
10259 | cpu_buf->base = mmap(NULL, pb->mmap_size + pb->page_size, | |
10260 | PROT_READ | PROT_WRITE, MAP_SHARED, | |
10261 | cpu_buf->fd, 0); | |
10262 | if (cpu_buf->base == MAP_FAILED) { | |
10263 | cpu_buf->base = NULL; | |
10264 | err = -errno; | |
be18010e KW |
10265 | pr_warn("failed to mmap perf buffer on cpu #%d: %s\n", |
10266 | cpu, libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
10267 | goto error; |
10268 | } | |
10269 | ||
10270 | if (ioctl(cpu_buf->fd, PERF_EVENT_IOC_ENABLE, 0) < 0) { | |
10271 | err = -errno; | |
be18010e KW |
10272 | pr_warn("failed to enable perf buffer event on cpu #%d: %s\n", |
10273 | cpu, libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
10274 | goto error; |
10275 | } | |
10276 | ||
10277 | return cpu_buf; | |
10278 | ||
10279 | error: | |
10280 | perf_buffer__free_cpu_buf(pb, cpu_buf); | |
10281 | return (struct perf_cpu_buf *)ERR_PTR(err); | |
10282 | } | |
10283 | ||
10284 | static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, | |
10285 | struct perf_buffer_params *p); | |
10286 | ||
10287 | struct perf_buffer *perf_buffer__new(int map_fd, size_t page_cnt, | |
10288 | const struct perf_buffer_opts *opts) | |
10289 | { | |
10290 | struct perf_buffer_params p = {}; | |
4be6e05c ACM |
10291 | struct perf_event_attr attr = { 0, }; |
10292 | ||
65bb2e0f | 10293 | attr.config = PERF_COUNT_SW_BPF_OUTPUT; |
4be6e05c ACM |
10294 | attr.type = PERF_TYPE_SOFTWARE; |
10295 | attr.sample_type = PERF_SAMPLE_RAW; | |
10296 | attr.sample_period = 1; | |
10297 | attr.wakeup_events = 1; | |
fb84b822 AN |
10298 | |
10299 | p.attr = &attr; | |
10300 | p.sample_cb = opts ? opts->sample_cb : NULL; | |
10301 | p.lost_cb = opts ? opts->lost_cb : NULL; | |
10302 | p.ctx = opts ? opts->ctx : NULL; | |
10303 | ||
10304 | return __perf_buffer__new(map_fd, page_cnt, &p); | |
10305 | } | |
10306 | ||
10307 | struct perf_buffer * | |
10308 | perf_buffer__new_raw(int map_fd, size_t page_cnt, | |
10309 | const struct perf_buffer_raw_opts *opts) | |
10310 | { | |
10311 | struct perf_buffer_params p = {}; | |
10312 | ||
10313 | p.attr = opts->attr; | |
10314 | p.event_cb = opts->event_cb; | |
10315 | p.ctx = opts->ctx; | |
10316 | p.cpu_cnt = opts->cpu_cnt; | |
10317 | p.cpus = opts->cpus; | |
10318 | p.map_keys = opts->map_keys; | |
10319 | ||
10320 | return __perf_buffer__new(map_fd, page_cnt, &p); | |
10321 | } | |
10322 | ||
10323 | static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, | |
10324 | struct perf_buffer_params *p) | |
10325 | { | |
783b8f01 | 10326 | const char *online_cpus_file = "/sys/devices/system/cpu/online"; |
0e289487 | 10327 | struct bpf_map_info map; |
fb84b822 AN |
10328 | char msg[STRERR_BUFSIZE]; |
10329 | struct perf_buffer *pb; | |
783b8f01 | 10330 | bool *online = NULL; |
fb84b822 | 10331 | __u32 map_info_len; |
783b8f01 | 10332 | int err, i, j, n; |
fb84b822 AN |
10333 | |
10334 | if (page_cnt & (page_cnt - 1)) { | |
be18010e KW |
10335 | pr_warn("page count should be power of two, but is %zu\n", |
10336 | page_cnt); | |
fb84b822 AN |
10337 | return ERR_PTR(-EINVAL); |
10338 | } | |
10339 | ||
0e289487 AN |
10340 | /* best-effort sanity checks */ |
10341 | memset(&map, 0, sizeof(map)); | |
fb84b822 AN |
10342 | map_info_len = sizeof(map); |
10343 | err = bpf_obj_get_info_by_fd(map_fd, &map, &map_info_len); | |
10344 | if (err) { | |
10345 | err = -errno; | |
0e289487 AN |
10346 | /* if BPF_OBJ_GET_INFO_BY_FD is supported, will return |
10347 | * -EBADFD, -EFAULT, or -E2BIG on real error | |
10348 | */ | |
10349 | if (err != -EINVAL) { | |
10350 | pr_warn("failed to get map info for map FD %d: %s\n", | |
10351 | map_fd, libbpf_strerror_r(err, msg, sizeof(msg))); | |
10352 | return ERR_PTR(err); | |
10353 | } | |
10354 | pr_debug("failed to get map info for FD %d; API not supported? Ignoring...\n", | |
10355 | map_fd); | |
10356 | } else { | |
10357 | if (map.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) { | |
10358 | pr_warn("map '%s' should be BPF_MAP_TYPE_PERF_EVENT_ARRAY\n", | |
10359 | map.name); | |
10360 | return ERR_PTR(-EINVAL); | |
10361 | } | |
fb84b822 AN |
10362 | } |
10363 | ||
10364 | pb = calloc(1, sizeof(*pb)); | |
10365 | if (!pb) | |
10366 | return ERR_PTR(-ENOMEM); | |
10367 | ||
10368 | pb->event_cb = p->event_cb; | |
10369 | pb->sample_cb = p->sample_cb; | |
10370 | pb->lost_cb = p->lost_cb; | |
10371 | pb->ctx = p->ctx; | |
10372 | ||
10373 | pb->page_size = getpagesize(); | |
10374 | pb->mmap_size = pb->page_size * page_cnt; | |
10375 | pb->map_fd = map_fd; | |
10376 | ||
10377 | pb->epoll_fd = epoll_create1(EPOLL_CLOEXEC); | |
10378 | if (pb->epoll_fd < 0) { | |
10379 | err = -errno; | |
be18010e KW |
10380 | pr_warn("failed to create epoll instance: %s\n", |
10381 | libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
10382 | goto error; |
10383 | } | |
10384 | ||
10385 | if (p->cpu_cnt > 0) { | |
10386 | pb->cpu_cnt = p->cpu_cnt; | |
10387 | } else { | |
10388 | pb->cpu_cnt = libbpf_num_possible_cpus(); | |
10389 | if (pb->cpu_cnt < 0) { | |
10390 | err = pb->cpu_cnt; | |
10391 | goto error; | |
10392 | } | |
0e289487 | 10393 | if (map.max_entries && map.max_entries < pb->cpu_cnt) |
fb84b822 AN |
10394 | pb->cpu_cnt = map.max_entries; |
10395 | } | |
10396 | ||
10397 | pb->events = calloc(pb->cpu_cnt, sizeof(*pb->events)); | |
10398 | if (!pb->events) { | |
10399 | err = -ENOMEM; | |
be18010e | 10400 | pr_warn("failed to allocate events: out of memory\n"); |
fb84b822 AN |
10401 | goto error; |
10402 | } | |
10403 | pb->cpu_bufs = calloc(pb->cpu_cnt, sizeof(*pb->cpu_bufs)); | |
10404 | if (!pb->cpu_bufs) { | |
10405 | err = -ENOMEM; | |
be18010e | 10406 | pr_warn("failed to allocate buffers: out of memory\n"); |
fb84b822 AN |
10407 | goto error; |
10408 | } | |
10409 | ||
783b8f01 AN |
10410 | err = parse_cpu_mask_file(online_cpus_file, &online, &n); |
10411 | if (err) { | |
10412 | pr_warn("failed to get online CPU mask: %d\n", err); | |
10413 | goto error; | |
10414 | } | |
10415 | ||
10416 | for (i = 0, j = 0; i < pb->cpu_cnt; i++) { | |
fb84b822 AN |
10417 | struct perf_cpu_buf *cpu_buf; |
10418 | int cpu, map_key; | |
10419 | ||
10420 | cpu = p->cpu_cnt > 0 ? p->cpus[i] : i; | |
10421 | map_key = p->cpu_cnt > 0 ? p->map_keys[i] : i; | |
10422 | ||
783b8f01 AN |
10423 | /* in case user didn't explicitly requested particular CPUs to |
10424 | * be attached to, skip offline/not present CPUs | |
10425 | */ | |
10426 | if (p->cpu_cnt <= 0 && (cpu >= n || !online[cpu])) | |
10427 | continue; | |
10428 | ||
fb84b822 AN |
10429 | cpu_buf = perf_buffer__open_cpu_buf(pb, p->attr, cpu, map_key); |
10430 | if (IS_ERR(cpu_buf)) { | |
10431 | err = PTR_ERR(cpu_buf); | |
10432 | goto error; | |
10433 | } | |
10434 | ||
783b8f01 | 10435 | pb->cpu_bufs[j] = cpu_buf; |
fb84b822 AN |
10436 | |
10437 | err = bpf_map_update_elem(pb->map_fd, &map_key, | |
10438 | &cpu_buf->fd, 0); | |
10439 | if (err) { | |
10440 | err = -errno; | |
be18010e KW |
10441 | pr_warn("failed to set cpu #%d, key %d -> perf FD %d: %s\n", |
10442 | cpu, map_key, cpu_buf->fd, | |
10443 | libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
10444 | goto error; |
10445 | } | |
10446 | ||
783b8f01 AN |
10447 | pb->events[j].events = EPOLLIN; |
10448 | pb->events[j].data.ptr = cpu_buf; | |
fb84b822 | 10449 | if (epoll_ctl(pb->epoll_fd, EPOLL_CTL_ADD, cpu_buf->fd, |
783b8f01 | 10450 | &pb->events[j]) < 0) { |
fb84b822 | 10451 | err = -errno; |
be18010e KW |
10452 | pr_warn("failed to epoll_ctl cpu #%d perf FD %d: %s\n", |
10453 | cpu, cpu_buf->fd, | |
10454 | libbpf_strerror_r(err, msg, sizeof(msg))); | |
fb84b822 AN |
10455 | goto error; |
10456 | } | |
783b8f01 | 10457 | j++; |
fb84b822 | 10458 | } |
783b8f01 AN |
10459 | pb->cpu_cnt = j; |
10460 | free(online); | |
fb84b822 AN |
10461 | |
10462 | return pb; | |
10463 | ||
10464 | error: | |
783b8f01 | 10465 | free(online); |
fb84b822 AN |
10466 | if (pb) |
10467 | perf_buffer__free(pb); | |
10468 | return ERR_PTR(err); | |
10469 | } | |
10470 | ||
10471 | struct perf_sample_raw { | |
10472 | struct perf_event_header header; | |
10473 | uint32_t size; | |
385bbf7b | 10474 | char data[]; |
fb84b822 AN |
10475 | }; |
10476 | ||
10477 | struct perf_sample_lost { | |
10478 | struct perf_event_header header; | |
10479 | uint64_t id; | |
10480 | uint64_t lost; | |
10481 | uint64_t sample_id; | |
10482 | }; | |
10483 | ||
10484 | static enum bpf_perf_event_ret | |
10485 | perf_buffer__process_record(struct perf_event_header *e, void *ctx) | |
10486 | { | |
10487 | struct perf_cpu_buf *cpu_buf = ctx; | |
10488 | struct perf_buffer *pb = cpu_buf->pb; | |
10489 | void *data = e; | |
10490 | ||
10491 | /* user wants full control over parsing perf event */ | |
10492 | if (pb->event_cb) | |
10493 | return pb->event_cb(pb->ctx, cpu_buf->cpu, e); | |
10494 | ||
10495 | switch (e->type) { | |
10496 | case PERF_RECORD_SAMPLE: { | |
10497 | struct perf_sample_raw *s = data; | |
10498 | ||
10499 | if (pb->sample_cb) | |
10500 | pb->sample_cb(pb->ctx, cpu_buf->cpu, s->data, s->size); | |
10501 | break; | |
10502 | } | |
10503 | case PERF_RECORD_LOST: { | |
10504 | struct perf_sample_lost *s = data; | |
10505 | ||
10506 | if (pb->lost_cb) | |
10507 | pb->lost_cb(pb->ctx, cpu_buf->cpu, s->lost); | |
10508 | break; | |
10509 | } | |
10510 | default: | |
be18010e | 10511 | pr_warn("unknown perf sample type %d\n", e->type); |
fb84b822 AN |
10512 | return LIBBPF_PERF_EVENT_ERROR; |
10513 | } | |
10514 | return LIBBPF_PERF_EVENT_CONT; | |
10515 | } | |
10516 | ||
10517 | static int perf_buffer__process_records(struct perf_buffer *pb, | |
10518 | struct perf_cpu_buf *cpu_buf) | |
10519 | { | |
10520 | enum bpf_perf_event_ret ret; | |
10521 | ||
10522 | ret = bpf_perf_event_read_simple(cpu_buf->base, pb->mmap_size, | |
10523 | pb->page_size, &cpu_buf->buf, | |
10524 | &cpu_buf->buf_size, | |
10525 | perf_buffer__process_record, cpu_buf); | |
10526 | if (ret != LIBBPF_PERF_EVENT_CONT) | |
10527 | return ret; | |
10528 | return 0; | |
10529 | } | |
10530 | ||
dca5612f AN |
10531 | int perf_buffer__epoll_fd(const struct perf_buffer *pb) |
10532 | { | |
10533 | return pb->epoll_fd; | |
10534 | } | |
10535 | ||
fb84b822 AN |
10536 | int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms) |
10537 | { | |
10538 | int i, cnt, err; | |
10539 | ||
10540 | cnt = epoll_wait(pb->epoll_fd, pb->events, pb->cpu_cnt, timeout_ms); | |
10541 | for (i = 0; i < cnt; i++) { | |
10542 | struct perf_cpu_buf *cpu_buf = pb->events[i].data.ptr; | |
10543 | ||
10544 | err = perf_buffer__process_records(pb, cpu_buf); | |
10545 | if (err) { | |
be18010e | 10546 | pr_warn("error while processing records: %d\n", err); |
fb84b822 AN |
10547 | return err; |
10548 | } | |
10549 | } | |
10550 | return cnt < 0 ? -errno : cnt; | |
10551 | } | |
10552 | ||
dca5612f AN |
10553 | /* Return number of PERF_EVENT_ARRAY map slots set up by this perf_buffer |
10554 | * manager. | |
10555 | */ | |
10556 | size_t perf_buffer__buffer_cnt(const struct perf_buffer *pb) | |
10557 | { | |
10558 | return pb->cpu_cnt; | |
10559 | } | |
10560 | ||
10561 | /* | |
10562 | * Return perf_event FD of a ring buffer in *buf_idx* slot of | |
10563 | * PERF_EVENT_ARRAY BPF map. This FD can be polled for new data using | |
10564 | * select()/poll()/epoll() Linux syscalls. | |
10565 | */ | |
10566 | int perf_buffer__buffer_fd(const struct perf_buffer *pb, size_t buf_idx) | |
10567 | { | |
10568 | struct perf_cpu_buf *cpu_buf; | |
10569 | ||
10570 | if (buf_idx >= pb->cpu_cnt) | |
10571 | return -EINVAL; | |
10572 | ||
10573 | cpu_buf = pb->cpu_bufs[buf_idx]; | |
10574 | if (!cpu_buf) | |
10575 | return -ENOENT; | |
10576 | ||
10577 | return cpu_buf->fd; | |
10578 | } | |
10579 | ||
10580 | /* | |
10581 | * Consume data from perf ring buffer corresponding to slot *buf_idx* in | |
10582 | * PERF_EVENT_ARRAY BPF map without waiting/polling. If there is no data to | |
10583 | * consume, do nothing and return success. | |
10584 | * Returns: | |
10585 | * - 0 on success; | |
10586 | * - <0 on failure. | |
10587 | */ | |
10588 | int perf_buffer__consume_buffer(struct perf_buffer *pb, size_t buf_idx) | |
10589 | { | |
10590 | struct perf_cpu_buf *cpu_buf; | |
10591 | ||
10592 | if (buf_idx >= pb->cpu_cnt) | |
10593 | return -EINVAL; | |
10594 | ||
10595 | cpu_buf = pb->cpu_bufs[buf_idx]; | |
10596 | if (!cpu_buf) | |
10597 | return -ENOENT; | |
10598 | ||
10599 | return perf_buffer__process_records(pb, cpu_buf); | |
10600 | } | |
10601 | ||
272d51af EC |
10602 | int perf_buffer__consume(struct perf_buffer *pb) |
10603 | { | |
10604 | int i, err; | |
10605 | ||
10606 | for (i = 0; i < pb->cpu_cnt; i++) { | |
10607 | struct perf_cpu_buf *cpu_buf = pb->cpu_bufs[i]; | |
10608 | ||
10609 | if (!cpu_buf) | |
10610 | continue; | |
10611 | ||
10612 | err = perf_buffer__process_records(pb, cpu_buf); | |
10613 | if (err) { | |
dca5612f | 10614 | pr_warn("perf_buffer: failed to process records in buffer #%d: %d\n", i, err); |
272d51af EC |
10615 | return err; |
10616 | } | |
10617 | } | |
10618 | return 0; | |
10619 | } | |
10620 | ||
34be1646 SL |
10621 | struct bpf_prog_info_array_desc { |
10622 | int array_offset; /* e.g. offset of jited_prog_insns */ | |
10623 | int count_offset; /* e.g. offset of jited_prog_len */ | |
10624 | int size_offset; /* > 0: offset of rec size, | |
10625 | * < 0: fix size of -size_offset | |
10626 | */ | |
10627 | }; | |
10628 | ||
10629 | static struct bpf_prog_info_array_desc bpf_prog_info_array_desc[] = { | |
10630 | [BPF_PROG_INFO_JITED_INSNS] = { | |
10631 | offsetof(struct bpf_prog_info, jited_prog_insns), | |
10632 | offsetof(struct bpf_prog_info, jited_prog_len), | |
10633 | -1, | |
10634 | }, | |
10635 | [BPF_PROG_INFO_XLATED_INSNS] = { | |
10636 | offsetof(struct bpf_prog_info, xlated_prog_insns), | |
10637 | offsetof(struct bpf_prog_info, xlated_prog_len), | |
10638 | -1, | |
10639 | }, | |
10640 | [BPF_PROG_INFO_MAP_IDS] = { | |
10641 | offsetof(struct bpf_prog_info, map_ids), | |
10642 | offsetof(struct bpf_prog_info, nr_map_ids), | |
10643 | -(int)sizeof(__u32), | |
10644 | }, | |
10645 | [BPF_PROG_INFO_JITED_KSYMS] = { | |
10646 | offsetof(struct bpf_prog_info, jited_ksyms), | |
10647 | offsetof(struct bpf_prog_info, nr_jited_ksyms), | |
10648 | -(int)sizeof(__u64), | |
10649 | }, | |
10650 | [BPF_PROG_INFO_JITED_FUNC_LENS] = { | |
10651 | offsetof(struct bpf_prog_info, jited_func_lens), | |
10652 | offsetof(struct bpf_prog_info, nr_jited_func_lens), | |
10653 | -(int)sizeof(__u32), | |
10654 | }, | |
10655 | [BPF_PROG_INFO_FUNC_INFO] = { | |
10656 | offsetof(struct bpf_prog_info, func_info), | |
10657 | offsetof(struct bpf_prog_info, nr_func_info), | |
10658 | offsetof(struct bpf_prog_info, func_info_rec_size), | |
10659 | }, | |
10660 | [BPF_PROG_INFO_LINE_INFO] = { | |
10661 | offsetof(struct bpf_prog_info, line_info), | |
10662 | offsetof(struct bpf_prog_info, nr_line_info), | |
10663 | offsetof(struct bpf_prog_info, line_info_rec_size), | |
10664 | }, | |
10665 | [BPF_PROG_INFO_JITED_LINE_INFO] = { | |
10666 | offsetof(struct bpf_prog_info, jited_line_info), | |
10667 | offsetof(struct bpf_prog_info, nr_jited_line_info), | |
10668 | offsetof(struct bpf_prog_info, jited_line_info_rec_size), | |
10669 | }, | |
10670 | [BPF_PROG_INFO_PROG_TAGS] = { | |
10671 | offsetof(struct bpf_prog_info, prog_tags), | |
10672 | offsetof(struct bpf_prog_info, nr_prog_tags), | |
10673 | -(int)sizeof(__u8) * BPF_TAG_SIZE, | |
10674 | }, | |
10675 | ||
10676 | }; | |
10677 | ||
8983b731 AN |
10678 | static __u32 bpf_prog_info_read_offset_u32(struct bpf_prog_info *info, |
10679 | int offset) | |
34be1646 SL |
10680 | { |
10681 | __u32 *array = (__u32 *)info; | |
10682 | ||
10683 | if (offset >= 0) | |
10684 | return array[offset / sizeof(__u32)]; | |
10685 | return -(int)offset; | |
10686 | } | |
10687 | ||
8983b731 AN |
10688 | static __u64 bpf_prog_info_read_offset_u64(struct bpf_prog_info *info, |
10689 | int offset) | |
34be1646 SL |
10690 | { |
10691 | __u64 *array = (__u64 *)info; | |
10692 | ||
10693 | if (offset >= 0) | |
10694 | return array[offset / sizeof(__u64)]; | |
10695 | return -(int)offset; | |
10696 | } | |
10697 | ||
10698 | static void bpf_prog_info_set_offset_u32(struct bpf_prog_info *info, int offset, | |
10699 | __u32 val) | |
10700 | { | |
10701 | __u32 *array = (__u32 *)info; | |
10702 | ||
10703 | if (offset >= 0) | |
10704 | array[offset / sizeof(__u32)] = val; | |
10705 | } | |
10706 | ||
10707 | static void bpf_prog_info_set_offset_u64(struct bpf_prog_info *info, int offset, | |
10708 | __u64 val) | |
10709 | { | |
10710 | __u64 *array = (__u64 *)info; | |
10711 | ||
10712 | if (offset >= 0) | |
10713 | array[offset / sizeof(__u64)] = val; | |
10714 | } | |
10715 | ||
10716 | struct bpf_prog_info_linear * | |
10717 | bpf_program__get_prog_info_linear(int fd, __u64 arrays) | |
10718 | { | |
10719 | struct bpf_prog_info_linear *info_linear; | |
10720 | struct bpf_prog_info info = {}; | |
10721 | __u32 info_len = sizeof(info); | |
10722 | __u32 data_len = 0; | |
10723 | int i, err; | |
10724 | void *ptr; | |
10725 | ||
10726 | if (arrays >> BPF_PROG_INFO_LAST_ARRAY) | |
10727 | return ERR_PTR(-EINVAL); | |
10728 | ||
10729 | /* step 1: get array dimensions */ | |
10730 | err = bpf_obj_get_info_by_fd(fd, &info, &info_len); | |
10731 | if (err) { | |
10732 | pr_debug("can't get prog info: %s", strerror(errno)); | |
10733 | return ERR_PTR(-EFAULT); | |
10734 | } | |
10735 | ||
10736 | /* step 2: calculate total size of all arrays */ | |
10737 | for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { | |
10738 | bool include_array = (arrays & (1UL << i)) > 0; | |
10739 | struct bpf_prog_info_array_desc *desc; | |
10740 | __u32 count, size; | |
10741 | ||
10742 | desc = bpf_prog_info_array_desc + i; | |
10743 | ||
10744 | /* kernel is too old to support this field */ | |
10745 | if (info_len < desc->array_offset + sizeof(__u32) || | |
10746 | info_len < desc->count_offset + sizeof(__u32) || | |
10747 | (desc->size_offset > 0 && info_len < desc->size_offset)) | |
10748 | include_array = false; | |
10749 | ||
10750 | if (!include_array) { | |
10751 | arrays &= ~(1UL << i); /* clear the bit */ | |
10752 | continue; | |
10753 | } | |
10754 | ||
10755 | count = bpf_prog_info_read_offset_u32(&info, desc->count_offset); | |
10756 | size = bpf_prog_info_read_offset_u32(&info, desc->size_offset); | |
10757 | ||
10758 | data_len += count * size; | |
10759 | } | |
10760 | ||
10761 | /* step 3: allocate continuous memory */ | |
10762 | data_len = roundup(data_len, sizeof(__u64)); | |
10763 | info_linear = malloc(sizeof(struct bpf_prog_info_linear) + data_len); | |
10764 | if (!info_linear) | |
10765 | return ERR_PTR(-ENOMEM); | |
10766 | ||
10767 | /* step 4: fill data to info_linear->info */ | |
10768 | info_linear->arrays = arrays; | |
10769 | memset(&info_linear->info, 0, sizeof(info)); | |
10770 | ptr = info_linear->data; | |
10771 | ||
10772 | for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { | |
10773 | struct bpf_prog_info_array_desc *desc; | |
10774 | __u32 count, size; | |
10775 | ||
10776 | if ((arrays & (1UL << i)) == 0) | |
10777 | continue; | |
10778 | ||
10779 | desc = bpf_prog_info_array_desc + i; | |
10780 | count = bpf_prog_info_read_offset_u32(&info, desc->count_offset); | |
10781 | size = bpf_prog_info_read_offset_u32(&info, desc->size_offset); | |
10782 | bpf_prog_info_set_offset_u32(&info_linear->info, | |
10783 | desc->count_offset, count); | |
10784 | bpf_prog_info_set_offset_u32(&info_linear->info, | |
10785 | desc->size_offset, size); | |
10786 | bpf_prog_info_set_offset_u64(&info_linear->info, | |
10787 | desc->array_offset, | |
10788 | ptr_to_u64(ptr)); | |
10789 | ptr += count * size; | |
10790 | } | |
10791 | ||
10792 | /* step 5: call syscall again to get required arrays */ | |
10793 | err = bpf_obj_get_info_by_fd(fd, &info_linear->info, &info_len); | |
10794 | if (err) { | |
10795 | pr_debug("can't get prog info: %s", strerror(errno)); | |
10796 | free(info_linear); | |
10797 | return ERR_PTR(-EFAULT); | |
10798 | } | |
10799 | ||
10800 | /* step 6: verify the data */ | |
10801 | for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { | |
10802 | struct bpf_prog_info_array_desc *desc; | |
10803 | __u32 v1, v2; | |
10804 | ||
10805 | if ((arrays & (1UL << i)) == 0) | |
10806 | continue; | |
10807 | ||
10808 | desc = bpf_prog_info_array_desc + i; | |
10809 | v1 = bpf_prog_info_read_offset_u32(&info, desc->count_offset); | |
10810 | v2 = bpf_prog_info_read_offset_u32(&info_linear->info, | |
10811 | desc->count_offset); | |
10812 | if (v1 != v2) | |
be18010e | 10813 | pr_warn("%s: mismatch in element count\n", __func__); |
34be1646 SL |
10814 | |
10815 | v1 = bpf_prog_info_read_offset_u32(&info, desc->size_offset); | |
10816 | v2 = bpf_prog_info_read_offset_u32(&info_linear->info, | |
10817 | desc->size_offset); | |
10818 | if (v1 != v2) | |
be18010e | 10819 | pr_warn("%s: mismatch in rec size\n", __func__); |
34be1646 SL |
10820 | } |
10821 | ||
10822 | /* step 7: update info_len and data_len */ | |
10823 | info_linear->info_len = sizeof(struct bpf_prog_info); | |
10824 | info_linear->data_len = data_len; | |
10825 | ||
10826 | return info_linear; | |
10827 | } | |
10828 | ||
10829 | void bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear) | |
10830 | { | |
10831 | int i; | |
10832 | ||
10833 | for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { | |
10834 | struct bpf_prog_info_array_desc *desc; | |
10835 | __u64 addr, offs; | |
10836 | ||
10837 | if ((info_linear->arrays & (1UL << i)) == 0) | |
10838 | continue; | |
10839 | ||
10840 | desc = bpf_prog_info_array_desc + i; | |
10841 | addr = bpf_prog_info_read_offset_u64(&info_linear->info, | |
10842 | desc->array_offset); | |
10843 | offs = addr - ptr_to_u64(info_linear->data); | |
10844 | bpf_prog_info_set_offset_u64(&info_linear->info, | |
10845 | desc->array_offset, offs); | |
10846 | } | |
10847 | } | |
10848 | ||
10849 | void bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear) | |
10850 | { | |
10851 | int i; | |
10852 | ||
10853 | for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { | |
10854 | struct bpf_prog_info_array_desc *desc; | |
10855 | __u64 addr, offs; | |
10856 | ||
10857 | if ((info_linear->arrays & (1UL << i)) == 0) | |
10858 | continue; | |
10859 | ||
10860 | desc = bpf_prog_info_array_desc + i; | |
10861 | offs = bpf_prog_info_read_offset_u64(&info_linear->info, | |
10862 | desc->array_offset); | |
10863 | addr = offs + ptr_to_u64(info_linear->data); | |
10864 | bpf_prog_info_set_offset_u64(&info_linear->info, | |
10865 | desc->array_offset, addr); | |
10866 | } | |
10867 | } | |
6446b315 | 10868 | |
ff26ce5c EC |
10869 | int bpf_program__set_attach_target(struct bpf_program *prog, |
10870 | int attach_prog_fd, | |
10871 | const char *attach_func_name) | |
10872 | { | |
10873 | int btf_id; | |
10874 | ||
10875 | if (!prog || attach_prog_fd < 0 || !attach_func_name) | |
10876 | return -EINVAL; | |
10877 | ||
10878 | if (attach_prog_fd) | |
10879 | btf_id = libbpf_find_prog_btf_id(attach_func_name, | |
10880 | attach_prog_fd); | |
10881 | else | |
8cee9107 LR |
10882 | btf_id = libbpf_find_vmlinux_btf_id(attach_func_name, |
10883 | prog->expected_attach_type); | |
ff26ce5c EC |
10884 | |
10885 | if (btf_id < 0) | |
10886 | return btf_id; | |
10887 | ||
10888 | prog->attach_btf_id = btf_id; | |
91abb4a6 | 10889 | prog->attach_btf_obj_fd = 0; |
ff26ce5c EC |
10890 | prog->attach_prog_fd = attach_prog_fd; |
10891 | return 0; | |
10892 | } | |
10893 | ||
6803ee25 | 10894 | int parse_cpu_mask_str(const char *s, bool **mask, int *mask_sz) |
6446b315 | 10895 | { |
6803ee25 AN |
10896 | int err = 0, n, len, start, end = -1; |
10897 | bool *tmp; | |
6446b315 | 10898 | |
6803ee25 AN |
10899 | *mask = NULL; |
10900 | *mask_sz = 0; | |
10901 | ||
10902 | /* Each sub string separated by ',' has format \d+-\d+ or \d+ */ | |
10903 | while (*s) { | |
10904 | if (*s == ',' || *s == '\n') { | |
10905 | s++; | |
10906 | continue; | |
10907 | } | |
10908 | n = sscanf(s, "%d%n-%d%n", &start, &len, &end, &len); | |
10909 | if (n <= 0 || n > 2) { | |
10910 | pr_warn("Failed to get CPU range %s: %d\n", s, n); | |
10911 | err = -EINVAL; | |
10912 | goto cleanup; | |
10913 | } else if (n == 1) { | |
10914 | end = start; | |
10915 | } | |
10916 | if (start < 0 || start > end) { | |
10917 | pr_warn("Invalid CPU range [%d,%d] in %s\n", | |
10918 | start, end, s); | |
10919 | err = -EINVAL; | |
10920 | goto cleanup; | |
10921 | } | |
10922 | tmp = realloc(*mask, end + 1); | |
10923 | if (!tmp) { | |
10924 | err = -ENOMEM; | |
10925 | goto cleanup; | |
10926 | } | |
10927 | *mask = tmp; | |
10928 | memset(tmp + *mask_sz, 0, start - *mask_sz); | |
10929 | memset(tmp + start, 1, end - start + 1); | |
10930 | *mask_sz = end + 1; | |
10931 | s += len; | |
10932 | } | |
10933 | if (!*mask_sz) { | |
10934 | pr_warn("Empty CPU range\n"); | |
10935 | return -EINVAL; | |
10936 | } | |
10937 | return 0; | |
10938 | cleanup: | |
10939 | free(*mask); | |
10940 | *mask = NULL; | |
10941 | return err; | |
10942 | } | |
10943 | ||
10944 | int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz) | |
10945 | { | |
10946 | int fd, err = 0, len; | |
10947 | char buf[128]; | |
6446b315 HL |
10948 | |
10949 | fd = open(fcpu, O_RDONLY); | |
10950 | if (fd < 0) { | |
6803ee25 AN |
10951 | err = -errno; |
10952 | pr_warn("Failed to open cpu mask file %s: %d\n", fcpu, err); | |
10953 | return err; | |
6446b315 HL |
10954 | } |
10955 | len = read(fd, buf, sizeof(buf)); | |
10956 | close(fd); | |
10957 | if (len <= 0) { | |
6803ee25 AN |
10958 | err = len ? -errno : -EINVAL; |
10959 | pr_warn("Failed to read cpu mask from %s: %d\n", fcpu, err); | |
10960 | return err; | |
6446b315 | 10961 | } |
6803ee25 AN |
10962 | if (len >= sizeof(buf)) { |
10963 | pr_warn("CPU mask is too big in file %s\n", fcpu); | |
10964 | return -E2BIG; | |
6446b315 HL |
10965 | } |
10966 | buf[len] = '\0'; | |
10967 | ||
6803ee25 AN |
10968 | return parse_cpu_mask_str(buf, mask, mask_sz); |
10969 | } | |
10970 | ||
10971 | int libbpf_num_possible_cpus(void) | |
10972 | { | |
10973 | static const char *fcpu = "/sys/devices/system/cpu/possible"; | |
10974 | static int cpus; | |
10975 | int err, n, i, tmp_cpus; | |
10976 | bool *mask; | |
10977 | ||
10978 | tmp_cpus = READ_ONCE(cpus); | |
10979 | if (tmp_cpus > 0) | |
10980 | return tmp_cpus; | |
10981 | ||
10982 | err = parse_cpu_mask_file(fcpu, &mask, &n); | |
10983 | if (err) | |
10984 | return err; | |
10985 | ||
10986 | tmp_cpus = 0; | |
10987 | for (i = 0; i < n; i++) { | |
10988 | if (mask[i]) | |
10989 | tmp_cpus++; | |
6446b315 | 10990 | } |
6803ee25 | 10991 | free(mask); |
56fbc241 TC |
10992 | |
10993 | WRITE_ONCE(cpus, tmp_cpus); | |
10994 | return tmp_cpus; | |
6446b315 | 10995 | } |
d66562fb AN |
10996 | |
10997 | int bpf_object__open_skeleton(struct bpf_object_skeleton *s, | |
10998 | const struct bpf_object_open_opts *opts) | |
10999 | { | |
11000 | DECLARE_LIBBPF_OPTS(bpf_object_open_opts, skel_opts, | |
11001 | .object_name = s->name, | |
11002 | ); | |
11003 | struct bpf_object *obj; | |
11004 | int i; | |
11005 | ||
11006 | /* Attempt to preserve opts->object_name, unless overriden by user | |
11007 | * explicitly. Overwriting object name for skeletons is discouraged, | |
11008 | * as it breaks global data maps, because they contain object name | |
11009 | * prefix as their own map name prefix. When skeleton is generated, | |
11010 | * bpftool is making an assumption that this name will stay the same. | |
11011 | */ | |
11012 | if (opts) { | |
11013 | memcpy(&skel_opts, opts, sizeof(*opts)); | |
11014 | if (!opts->object_name) | |
11015 | skel_opts.object_name = s->name; | |
11016 | } | |
11017 | ||
11018 | obj = bpf_object__open_mem(s->data, s->data_sz, &skel_opts); | |
11019 | if (IS_ERR(obj)) { | |
11020 | pr_warn("failed to initialize skeleton BPF object '%s': %ld\n", | |
11021 | s->name, PTR_ERR(obj)); | |
11022 | return PTR_ERR(obj); | |
11023 | } | |
11024 | ||
11025 | *s->obj = obj; | |
11026 | ||
11027 | for (i = 0; i < s->map_cnt; i++) { | |
11028 | struct bpf_map **map = s->maps[i].map; | |
11029 | const char *name = s->maps[i].name; | |
11030 | void **mmaped = s->maps[i].mmaped; | |
11031 | ||
11032 | *map = bpf_object__find_map_by_name(obj, name); | |
11033 | if (!*map) { | |
11034 | pr_warn("failed to find skeleton map '%s'\n", name); | |
11035 | return -ESRCH; | |
11036 | } | |
11037 | ||
2ad97d47 | 11038 | /* externs shouldn't be pre-setup from user code */ |
81bfdd08 | 11039 | if (mmaped && (*map)->libbpf_type != LIBBPF_MAP_KCONFIG) |
d66562fb AN |
11040 | *mmaped = (*map)->mmaped; |
11041 | } | |
11042 | ||
11043 | for (i = 0; i < s->prog_cnt; i++) { | |
11044 | struct bpf_program **prog = s->progs[i].prog; | |
11045 | const char *name = s->progs[i].name; | |
11046 | ||
11047 | *prog = bpf_object__find_program_by_name(obj, name); | |
11048 | if (!*prog) { | |
11049 | pr_warn("failed to find skeleton program '%s'\n", name); | |
11050 | return -ESRCH; | |
11051 | } | |
11052 | } | |
11053 | ||
11054 | return 0; | |
11055 | } | |
11056 | ||
11057 | int bpf_object__load_skeleton(struct bpf_object_skeleton *s) | |
11058 | { | |
11059 | int i, err; | |
11060 | ||
11061 | err = bpf_object__load(*s->obj); | |
11062 | if (err) { | |
11063 | pr_warn("failed to load BPF skeleton '%s': %d\n", s->name, err); | |
11064 | return err; | |
11065 | } | |
11066 | ||
11067 | for (i = 0; i < s->map_cnt; i++) { | |
11068 | struct bpf_map *map = *s->maps[i].map; | |
11069 | size_t mmap_sz = bpf_map_mmap_sz(map); | |
11070 | int prot, map_fd = bpf_map__fd(map); | |
11071 | void **mmaped = s->maps[i].mmaped; | |
d66562fb AN |
11072 | |
11073 | if (!mmaped) | |
11074 | continue; | |
11075 | ||
11076 | if (!(map->def.map_flags & BPF_F_MMAPABLE)) { | |
11077 | *mmaped = NULL; | |
11078 | continue; | |
11079 | } | |
11080 | ||
11081 | if (map->def.map_flags & BPF_F_RDONLY_PROG) | |
11082 | prot = PROT_READ; | |
11083 | else | |
11084 | prot = PROT_READ | PROT_WRITE; | |
11085 | ||
11086 | /* Remap anonymous mmap()-ed "map initialization image" as | |
11087 | * a BPF map-backed mmap()-ed memory, but preserving the same | |
11088 | * memory address. This will cause kernel to change process' | |
11089 | * page table to point to a different piece of kernel memory, | |
11090 | * but from userspace point of view memory address (and its | |
11091 | * contents, being identical at this point) will stay the | |
11092 | * same. This mapping will be released by bpf_object__close() | |
11093 | * as per normal clean up procedure, so we don't need to worry | |
11094 | * about it from skeleton's clean up perspective. | |
11095 | */ | |
2ad97d47 AN |
11096 | *mmaped = mmap(map->mmaped, mmap_sz, prot, |
11097 | MAP_SHARED | MAP_FIXED, map_fd, 0); | |
11098 | if (*mmaped == MAP_FAILED) { | |
d66562fb AN |
11099 | err = -errno; |
11100 | *mmaped = NULL; | |
11101 | pr_warn("failed to re-mmap() map '%s': %d\n", | |
11102 | bpf_map__name(map), err); | |
11103 | return err; | |
11104 | } | |
11105 | } | |
11106 | ||
11107 | return 0; | |
11108 | } | |
11109 | ||
11110 | int bpf_object__attach_skeleton(struct bpf_object_skeleton *s) | |
11111 | { | |
11112 | int i; | |
11113 | ||
11114 | for (i = 0; i < s->prog_cnt; i++) { | |
11115 | struct bpf_program *prog = *s->progs[i].prog; | |
11116 | struct bpf_link **link = s->progs[i].link; | |
11117 | const struct bpf_sec_def *sec_def; | |
d66562fb | 11118 | |
d9297581 AN |
11119 | if (!prog->load) |
11120 | continue; | |
11121 | ||
52109584 | 11122 | sec_def = find_sec_def(prog->sec_name); |
d66562fb AN |
11123 | if (!sec_def || !sec_def->attach_fn) |
11124 | continue; | |
11125 | ||
11126 | *link = sec_def->attach_fn(sec_def, prog); | |
11127 | if (IS_ERR(*link)) { | |
11128 | pr_warn("failed to auto-attach program '%s': %ld\n", | |
11129 | bpf_program__name(prog), PTR_ERR(*link)); | |
11130 | return PTR_ERR(*link); | |
11131 | } | |
11132 | } | |
11133 | ||
11134 | return 0; | |
11135 | } | |
11136 | ||
11137 | void bpf_object__detach_skeleton(struct bpf_object_skeleton *s) | |
11138 | { | |
11139 | int i; | |
11140 | ||
11141 | for (i = 0; i < s->prog_cnt; i++) { | |
11142 | struct bpf_link **link = s->progs[i].link; | |
11143 | ||
50450fc7 | 11144 | bpf_link__destroy(*link); |
d66562fb AN |
11145 | *link = NULL; |
11146 | } | |
11147 | } | |
11148 | ||
11149 | void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s) | |
11150 | { | |
11151 | if (s->progs) | |
11152 | bpf_object__detach_skeleton(s); | |
11153 | if (s->obj) | |
11154 | bpf_object__close(*s->obj); | |
11155 | free(s->maps); | |
11156 | free(s->progs); | |
11157 | free(s); | |
11158 | } |