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179a0cc4 | 1 | // SPDX-License-Identifier: GPL-2.0 |
2541517c | 2 | /* Copyright (c) 2011-2015 PLUMgrid, http://plumgrid.com |
0515e599 | 3 | * Copyright (c) 2016 Facebook |
2541517c AS |
4 | */ |
5 | #include <linux/kernel.h> | |
6 | #include <linux/types.h> | |
7 | #include <linux/slab.h> | |
8 | #include <linux/bpf.h> | |
0515e599 | 9 | #include <linux/bpf_perf_event.h> |
2541517c AS |
10 | #include <linux/filter.h> |
11 | #include <linux/uaccess.h> | |
9c959c86 | 12 | #include <linux/ctype.h> |
9802d865 | 13 | #include <linux/kprobes.h> |
41bdc4b4 | 14 | #include <linux/syscalls.h> |
540adea3 | 15 | #include <linux/error-injection.h> |
9802d865 | 16 | |
c7b6f29b NA |
17 | #include <asm/tlb.h> |
18 | ||
9802d865 | 19 | #include "trace_probe.h" |
2541517c AS |
20 | #include "trace.h" |
21 | ||
e672db03 SF |
22 | #define bpf_event_rcu_dereference(p) \ |
23 | rcu_dereference_protected(p, lockdep_is_held(&bpf_event_mutex)) | |
24 | ||
a38d1107 MM |
25 | #ifdef CONFIG_MODULES |
26 | struct bpf_trace_module { | |
27 | struct module *module; | |
28 | struct list_head list; | |
29 | }; | |
30 | ||
31 | static LIST_HEAD(bpf_trace_modules); | |
32 | static DEFINE_MUTEX(bpf_module_mutex); | |
33 | ||
34 | static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name) | |
35 | { | |
36 | struct bpf_raw_event_map *btp, *ret = NULL; | |
37 | struct bpf_trace_module *btm; | |
38 | unsigned int i; | |
39 | ||
40 | mutex_lock(&bpf_module_mutex); | |
41 | list_for_each_entry(btm, &bpf_trace_modules, list) { | |
42 | for (i = 0; i < btm->module->num_bpf_raw_events; ++i) { | |
43 | btp = &btm->module->bpf_raw_events[i]; | |
44 | if (!strcmp(btp->tp->name, name)) { | |
45 | if (try_module_get(btm->module)) | |
46 | ret = btp; | |
47 | goto out; | |
48 | } | |
49 | } | |
50 | } | |
51 | out: | |
52 | mutex_unlock(&bpf_module_mutex); | |
53 | return ret; | |
54 | } | |
55 | #else | |
56 | static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name) | |
57 | { | |
58 | return NULL; | |
59 | } | |
60 | #endif /* CONFIG_MODULES */ | |
61 | ||
035226b9 | 62 | u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); |
c195651e | 63 | u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); |
035226b9 | 64 | |
2541517c AS |
65 | /** |
66 | * trace_call_bpf - invoke BPF program | |
e87c6bc3 | 67 | * @call: tracepoint event |
2541517c AS |
68 | * @ctx: opaque context pointer |
69 | * | |
70 | * kprobe handlers execute BPF programs via this helper. | |
71 | * Can be used from static tracepoints in the future. | |
72 | * | |
73 | * Return: BPF programs always return an integer which is interpreted by | |
74 | * kprobe handler as: | |
75 | * 0 - return from kprobe (event is filtered out) | |
76 | * 1 - store kprobe event into ring buffer | |
77 | * Other values are reserved and currently alias to 1 | |
78 | */ | |
e87c6bc3 | 79 | unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx) |
2541517c AS |
80 | { |
81 | unsigned int ret; | |
82 | ||
83 | if (in_nmi()) /* not supported yet */ | |
84 | return 1; | |
85 | ||
b0a81b94 | 86 | cant_sleep(); |
2541517c AS |
87 | |
88 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) { | |
89 | /* | |
90 | * since some bpf program is already running on this cpu, | |
91 | * don't call into another bpf program (same or different) | |
92 | * and don't send kprobe event into ring-buffer, | |
93 | * so return zero here | |
94 | */ | |
95 | ret = 0; | |
96 | goto out; | |
97 | } | |
98 | ||
e87c6bc3 YS |
99 | /* |
100 | * Instead of moving rcu_read_lock/rcu_dereference/rcu_read_unlock | |
101 | * to all call sites, we did a bpf_prog_array_valid() there to check | |
102 | * whether call->prog_array is empty or not, which is | |
103 | * a heurisitc to speed up execution. | |
104 | * | |
105 | * If bpf_prog_array_valid() fetched prog_array was | |
106 | * non-NULL, we go into trace_call_bpf() and do the actual | |
107 | * proper rcu_dereference() under RCU lock. | |
108 | * If it turns out that prog_array is NULL then, we bail out. | |
109 | * For the opposite, if the bpf_prog_array_valid() fetched pointer | |
110 | * was NULL, you'll skip the prog_array with the risk of missing | |
111 | * out of events when it was updated in between this and the | |
112 | * rcu_dereference() which is accepted risk. | |
113 | */ | |
114 | ret = BPF_PROG_RUN_ARRAY_CHECK(call->prog_array, ctx, BPF_PROG_RUN); | |
2541517c AS |
115 | |
116 | out: | |
117 | __this_cpu_dec(bpf_prog_active); | |
2541517c AS |
118 | |
119 | return ret; | |
120 | } | |
2541517c | 121 | |
9802d865 JB |
122 | #ifdef CONFIG_BPF_KPROBE_OVERRIDE |
123 | BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc) | |
124 | { | |
9802d865 | 125 | regs_set_return_value(regs, rc); |
540adea3 | 126 | override_function_with_return(regs); |
9802d865 JB |
127 | return 0; |
128 | } | |
129 | ||
130 | static const struct bpf_func_proto bpf_override_return_proto = { | |
131 | .func = bpf_override_return, | |
132 | .gpl_only = true, | |
133 | .ret_type = RET_INTEGER, | |
134 | .arg1_type = ARG_PTR_TO_CTX, | |
135 | .arg2_type = ARG_ANYTHING, | |
136 | }; | |
137 | #endif | |
138 | ||
8d92db5c CH |
139 | static __always_inline int |
140 | bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr) | |
2541517c | 141 | { |
8d92db5c | 142 | int ret; |
2541517c | 143 | |
8d92db5c | 144 | ret = probe_user_read(dst, unsafe_ptr, size); |
6ae08ae3 DB |
145 | if (unlikely(ret < 0)) |
146 | memset(dst, 0, size); | |
6ae08ae3 DB |
147 | return ret; |
148 | } | |
149 | ||
8d92db5c CH |
150 | BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size, |
151 | const void __user *, unsafe_ptr) | |
152 | { | |
153 | return bpf_probe_read_user_common(dst, size, unsafe_ptr); | |
154 | } | |
155 | ||
f470378c | 156 | const struct bpf_func_proto bpf_probe_read_user_proto = { |
6ae08ae3 DB |
157 | .func = bpf_probe_read_user, |
158 | .gpl_only = true, | |
159 | .ret_type = RET_INTEGER, | |
160 | .arg1_type = ARG_PTR_TO_UNINIT_MEM, | |
161 | .arg2_type = ARG_CONST_SIZE_OR_ZERO, | |
162 | .arg3_type = ARG_ANYTHING, | |
163 | }; | |
164 | ||
8d92db5c CH |
165 | static __always_inline int |
166 | bpf_probe_read_user_str_common(void *dst, u32 size, | |
167 | const void __user *unsafe_ptr) | |
6ae08ae3 | 168 | { |
8d92db5c | 169 | int ret; |
6ae08ae3 | 170 | |
8d92db5c | 171 | ret = strncpy_from_user_nofault(dst, unsafe_ptr, size); |
6ae08ae3 DB |
172 | if (unlikely(ret < 0)) |
173 | memset(dst, 0, size); | |
6ae08ae3 DB |
174 | return ret; |
175 | } | |
176 | ||
8d92db5c CH |
177 | BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size, |
178 | const void __user *, unsafe_ptr) | |
179 | { | |
180 | return bpf_probe_read_user_str_common(dst, size, unsafe_ptr); | |
181 | } | |
182 | ||
f470378c | 183 | const struct bpf_func_proto bpf_probe_read_user_str_proto = { |
6ae08ae3 DB |
184 | .func = bpf_probe_read_user_str, |
185 | .gpl_only = true, | |
186 | .ret_type = RET_INTEGER, | |
187 | .arg1_type = ARG_PTR_TO_UNINIT_MEM, | |
188 | .arg2_type = ARG_CONST_SIZE_OR_ZERO, | |
189 | .arg3_type = ARG_ANYTHING, | |
190 | }; | |
191 | ||
192 | static __always_inline int | |
8d92db5c | 193 | bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr) |
6ae08ae3 DB |
194 | { |
195 | int ret = security_locked_down(LOCKDOWN_BPF_READ); | |
9d1f8be5 | 196 | |
6ae08ae3 | 197 | if (unlikely(ret < 0)) |
8d92db5c | 198 | goto fail; |
fe557319 | 199 | ret = copy_from_kernel_nofault(dst, unsafe_ptr, size); |
074f528e | 200 | if (unlikely(ret < 0)) |
8d92db5c CH |
201 | goto fail; |
202 | return ret; | |
203 | fail: | |
204 | memset(dst, 0, size); | |
6ae08ae3 DB |
205 | return ret; |
206 | } | |
074f528e | 207 | |
6ae08ae3 DB |
208 | BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size, |
209 | const void *, unsafe_ptr) | |
210 | { | |
8d92db5c | 211 | return bpf_probe_read_kernel_common(dst, size, unsafe_ptr); |
6ae08ae3 DB |
212 | } |
213 | ||
f470378c | 214 | const struct bpf_func_proto bpf_probe_read_kernel_proto = { |
6ae08ae3 DB |
215 | .func = bpf_probe_read_kernel, |
216 | .gpl_only = true, | |
217 | .ret_type = RET_INTEGER, | |
218 | .arg1_type = ARG_PTR_TO_UNINIT_MEM, | |
219 | .arg2_type = ARG_CONST_SIZE_OR_ZERO, | |
220 | .arg3_type = ARG_ANYTHING, | |
221 | }; | |
222 | ||
6ae08ae3 | 223 | static __always_inline int |
8d92db5c | 224 | bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr) |
6ae08ae3 DB |
225 | { |
226 | int ret = security_locked_down(LOCKDOWN_BPF_READ); | |
227 | ||
228 | if (unlikely(ret < 0)) | |
8d92db5c CH |
229 | goto fail; |
230 | ||
6ae08ae3 | 231 | /* |
8d92db5c CH |
232 | * The strncpy_from_kernel_nofault() call will likely not fill the |
233 | * entire buffer, but that's okay in this circumstance as we're probing | |
6ae08ae3 DB |
234 | * arbitrary memory anyway similar to bpf_probe_read_*() and might |
235 | * as well probe the stack. Thus, memory is explicitly cleared | |
236 | * only in error case, so that improper users ignoring return | |
237 | * code altogether don't copy garbage; otherwise length of string | |
238 | * is returned that can be used for bpf_perf_event_output() et al. | |
239 | */ | |
8d92db5c | 240 | ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size); |
6ae08ae3 | 241 | if (unlikely(ret < 0)) |
8d92db5c CH |
242 | goto fail; |
243 | ||
244 | return 0; | |
245 | fail: | |
246 | memset(dst, 0, size); | |
074f528e | 247 | return ret; |
2541517c AS |
248 | } |
249 | ||
6ae08ae3 DB |
250 | BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size, |
251 | const void *, unsafe_ptr) | |
252 | { | |
8d92db5c | 253 | return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr); |
6ae08ae3 DB |
254 | } |
255 | ||
f470378c | 256 | const struct bpf_func_proto bpf_probe_read_kernel_str_proto = { |
6ae08ae3 DB |
257 | .func = bpf_probe_read_kernel_str, |
258 | .gpl_only = true, | |
259 | .ret_type = RET_INTEGER, | |
260 | .arg1_type = ARG_PTR_TO_UNINIT_MEM, | |
261 | .arg2_type = ARG_CONST_SIZE_OR_ZERO, | |
262 | .arg3_type = ARG_ANYTHING, | |
263 | }; | |
264 | ||
8d92db5c CH |
265 | #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE |
266 | BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size, | |
267 | const void *, unsafe_ptr) | |
268 | { | |
269 | if ((unsigned long)unsafe_ptr < TASK_SIZE) { | |
270 | return bpf_probe_read_user_common(dst, size, | |
271 | (__force void __user *)unsafe_ptr); | |
272 | } | |
273 | return bpf_probe_read_kernel_common(dst, size, unsafe_ptr); | |
274 | } | |
275 | ||
276 | static const struct bpf_func_proto bpf_probe_read_compat_proto = { | |
277 | .func = bpf_probe_read_compat, | |
278 | .gpl_only = true, | |
279 | .ret_type = RET_INTEGER, | |
280 | .arg1_type = ARG_PTR_TO_UNINIT_MEM, | |
281 | .arg2_type = ARG_CONST_SIZE_OR_ZERO, | |
282 | .arg3_type = ARG_ANYTHING, | |
283 | }; | |
284 | ||
6ae08ae3 DB |
285 | BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size, |
286 | const void *, unsafe_ptr) | |
287 | { | |
8d92db5c CH |
288 | if ((unsigned long)unsafe_ptr < TASK_SIZE) { |
289 | return bpf_probe_read_user_str_common(dst, size, | |
290 | (__force void __user *)unsafe_ptr); | |
291 | } | |
292 | return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr); | |
6ae08ae3 DB |
293 | } |
294 | ||
295 | static const struct bpf_func_proto bpf_probe_read_compat_str_proto = { | |
296 | .func = bpf_probe_read_compat_str, | |
2541517c AS |
297 | .gpl_only = true, |
298 | .ret_type = RET_INTEGER, | |
39f19ebb | 299 | .arg1_type = ARG_PTR_TO_UNINIT_MEM, |
9c019e2b | 300 | .arg2_type = ARG_CONST_SIZE_OR_ZERO, |
2541517c AS |
301 | .arg3_type = ARG_ANYTHING, |
302 | }; | |
8d92db5c | 303 | #endif /* CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE */ |
2541517c | 304 | |
eb1b6688 | 305 | BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src, |
f3694e00 | 306 | u32, size) |
96ae5227 | 307 | { |
96ae5227 SD |
308 | /* |
309 | * Ensure we're in user context which is safe for the helper to | |
310 | * run. This helper has no business in a kthread. | |
311 | * | |
312 | * access_ok() should prevent writing to non-user memory, but in | |
313 | * some situations (nommu, temporary switch, etc) access_ok() does | |
314 | * not provide enough validation, hence the check on KERNEL_DS. | |
c7b6f29b NA |
315 | * |
316 | * nmi_uaccess_okay() ensures the probe is not run in an interim | |
317 | * state, when the task or mm are switched. This is specifically | |
318 | * required to prevent the use of temporary mm. | |
96ae5227 SD |
319 | */ |
320 | ||
321 | if (unlikely(in_interrupt() || | |
322 | current->flags & (PF_KTHREAD | PF_EXITING))) | |
323 | return -EPERM; | |
db68ce10 | 324 | if (unlikely(uaccess_kernel())) |
96ae5227 | 325 | return -EPERM; |
c7b6f29b NA |
326 | if (unlikely(!nmi_uaccess_okay())) |
327 | return -EPERM; | |
96ae5227 | 328 | |
eb1b6688 | 329 | return probe_user_write(unsafe_ptr, src, size); |
96ae5227 SD |
330 | } |
331 | ||
332 | static const struct bpf_func_proto bpf_probe_write_user_proto = { | |
333 | .func = bpf_probe_write_user, | |
334 | .gpl_only = true, | |
335 | .ret_type = RET_INTEGER, | |
336 | .arg1_type = ARG_ANYTHING, | |
39f19ebb AS |
337 | .arg2_type = ARG_PTR_TO_MEM, |
338 | .arg3_type = ARG_CONST_SIZE, | |
96ae5227 SD |
339 | }; |
340 | ||
341 | static const struct bpf_func_proto *bpf_get_probe_write_proto(void) | |
342 | { | |
2c78ee89 AS |
343 | if (!capable(CAP_SYS_ADMIN)) |
344 | return NULL; | |
345 | ||
96ae5227 SD |
346 | pr_warn_ratelimited("%s[%d] is installing a program with bpf_probe_write_user helper that may corrupt user memory!", |
347 | current->comm, task_pid_nr(current)); | |
348 | ||
349 | return &bpf_probe_write_user_proto; | |
350 | } | |
351 | ||
d7b2977b CH |
352 | static void bpf_trace_copy_string(char *buf, void *unsafe_ptr, char fmt_ptype, |
353 | size_t bufsz) | |
354 | { | |
355 | void __user *user_ptr = (__force void __user *)unsafe_ptr; | |
356 | ||
357 | buf[0] = 0; | |
358 | ||
359 | switch (fmt_ptype) { | |
360 | case 's': | |
361 | #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE | |
aec6ce59 CH |
362 | if ((unsigned long)unsafe_ptr < TASK_SIZE) { |
363 | strncpy_from_user_nofault(buf, user_ptr, bufsz); | |
364 | break; | |
365 | } | |
366 | fallthrough; | |
d7b2977b CH |
367 | #endif |
368 | case 'k': | |
369 | strncpy_from_kernel_nofault(buf, unsafe_ptr, bufsz); | |
370 | break; | |
371 | case 'u': | |
372 | strncpy_from_user_nofault(buf, user_ptr, bufsz); | |
373 | break; | |
374 | } | |
375 | } | |
376 | ||
9c959c86 | 377 | /* |
7bda4b40 | 378 | * Only limited trace_printk() conversion specifiers allowed: |
b2a5212f | 379 | * %d %i %u %x %ld %li %lu %lx %lld %lli %llu %llx %p %pks %pus %s |
9c959c86 | 380 | */ |
f3694e00 DB |
381 | BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1, |
382 | u64, arg2, u64, arg3) | |
9c959c86 | 383 | { |
b2a5212f DB |
384 | int i, mod[3] = {}, fmt_cnt = 0; |
385 | char buf[64], fmt_ptype; | |
386 | void *unsafe_ptr = NULL; | |
8d3b7dce | 387 | bool str_seen = false; |
9c959c86 AS |
388 | |
389 | /* | |
390 | * bpf_check()->check_func_arg()->check_stack_boundary() | |
391 | * guarantees that fmt points to bpf program stack, | |
392 | * fmt_size bytes of it were initialized and fmt_size > 0 | |
393 | */ | |
394 | if (fmt[--fmt_size] != 0) | |
395 | return -EINVAL; | |
396 | ||
397 | /* check format string for allowed specifiers */ | |
398 | for (i = 0; i < fmt_size; i++) { | |
399 | if ((!isprint(fmt[i]) && !isspace(fmt[i])) || !isascii(fmt[i])) | |
400 | return -EINVAL; | |
401 | ||
402 | if (fmt[i] != '%') | |
403 | continue; | |
404 | ||
405 | if (fmt_cnt >= 3) | |
406 | return -EINVAL; | |
407 | ||
408 | /* fmt[i] != 0 && fmt[last] == 0, so we can access fmt[i + 1] */ | |
409 | i++; | |
410 | if (fmt[i] == 'l') { | |
411 | mod[fmt_cnt]++; | |
412 | i++; | |
b2a5212f | 413 | } else if (fmt[i] == 'p') { |
9c959c86 | 414 | mod[fmt_cnt]++; |
b2a5212f DB |
415 | if ((fmt[i + 1] == 'k' || |
416 | fmt[i + 1] == 'u') && | |
417 | fmt[i + 2] == 's') { | |
418 | fmt_ptype = fmt[i + 1]; | |
419 | i += 2; | |
420 | goto fmt_str; | |
421 | } | |
422 | ||
1efb6ee3 MP |
423 | /* disallow any further format extensions */ |
424 | if (fmt[i + 1] != 0 && | |
425 | !isspace(fmt[i + 1]) && | |
426 | !ispunct(fmt[i + 1])) | |
9c959c86 | 427 | return -EINVAL; |
b2a5212f DB |
428 | |
429 | goto fmt_next; | |
430 | } else if (fmt[i] == 's') { | |
431 | mod[fmt_cnt]++; | |
432 | fmt_ptype = fmt[i]; | |
433 | fmt_str: | |
434 | if (str_seen) | |
435 | /* allow only one '%s' per fmt string */ | |
436 | return -EINVAL; | |
437 | str_seen = true; | |
438 | ||
439 | if (fmt[i + 1] != 0 && | |
440 | !isspace(fmt[i + 1]) && | |
441 | !ispunct(fmt[i + 1])) | |
442 | return -EINVAL; | |
443 | ||
444 | switch (fmt_cnt) { | |
445 | case 0: | |
446 | unsafe_ptr = (void *)(long)arg1; | |
447 | arg1 = (long)buf; | |
448 | break; | |
449 | case 1: | |
450 | unsafe_ptr = (void *)(long)arg2; | |
451 | arg2 = (long)buf; | |
452 | break; | |
453 | case 2: | |
454 | unsafe_ptr = (void *)(long)arg3; | |
455 | arg3 = (long)buf; | |
456 | break; | |
457 | } | |
458 | ||
d7b2977b CH |
459 | bpf_trace_copy_string(buf, unsafe_ptr, fmt_ptype, |
460 | sizeof(buf)); | |
b2a5212f | 461 | goto fmt_next; |
9c959c86 AS |
462 | } |
463 | ||
464 | if (fmt[i] == 'l') { | |
465 | mod[fmt_cnt]++; | |
466 | i++; | |
467 | } | |
468 | ||
7bda4b40 JF |
469 | if (fmt[i] != 'i' && fmt[i] != 'd' && |
470 | fmt[i] != 'u' && fmt[i] != 'x') | |
9c959c86 | 471 | return -EINVAL; |
b2a5212f | 472 | fmt_next: |
9c959c86 AS |
473 | fmt_cnt++; |
474 | } | |
475 | ||
88a5c690 DB |
476 | /* Horrid workaround for getting va_list handling working with different |
477 | * argument type combinations generically for 32 and 64 bit archs. | |
478 | */ | |
479 | #define __BPF_TP_EMIT() __BPF_ARG3_TP() | |
480 | #define __BPF_TP(...) \ | |
eefa864a | 481 | __trace_printk(0 /* Fake ip */, \ |
88a5c690 DB |
482 | fmt, ##__VA_ARGS__) |
483 | ||
484 | #define __BPF_ARG1_TP(...) \ | |
485 | ((mod[0] == 2 || (mod[0] == 1 && __BITS_PER_LONG == 64)) \ | |
486 | ? __BPF_TP(arg1, ##__VA_ARGS__) \ | |
487 | : ((mod[0] == 1 || (mod[0] == 0 && __BITS_PER_LONG == 32)) \ | |
488 | ? __BPF_TP((long)arg1, ##__VA_ARGS__) \ | |
489 | : __BPF_TP((u32)arg1, ##__VA_ARGS__))) | |
490 | ||
491 | #define __BPF_ARG2_TP(...) \ | |
492 | ((mod[1] == 2 || (mod[1] == 1 && __BITS_PER_LONG == 64)) \ | |
493 | ? __BPF_ARG1_TP(arg2, ##__VA_ARGS__) \ | |
494 | : ((mod[1] == 1 || (mod[1] == 0 && __BITS_PER_LONG == 32)) \ | |
495 | ? __BPF_ARG1_TP((long)arg2, ##__VA_ARGS__) \ | |
496 | : __BPF_ARG1_TP((u32)arg2, ##__VA_ARGS__))) | |
497 | ||
498 | #define __BPF_ARG3_TP(...) \ | |
499 | ((mod[2] == 2 || (mod[2] == 1 && __BITS_PER_LONG == 64)) \ | |
500 | ? __BPF_ARG2_TP(arg3, ##__VA_ARGS__) \ | |
501 | : ((mod[2] == 1 || (mod[2] == 0 && __BITS_PER_LONG == 32)) \ | |
502 | ? __BPF_ARG2_TP((long)arg3, ##__VA_ARGS__) \ | |
503 | : __BPF_ARG2_TP((u32)arg3, ##__VA_ARGS__))) | |
504 | ||
505 | return __BPF_TP_EMIT(); | |
9c959c86 AS |
506 | } |
507 | ||
508 | static const struct bpf_func_proto bpf_trace_printk_proto = { | |
509 | .func = bpf_trace_printk, | |
510 | .gpl_only = true, | |
511 | .ret_type = RET_INTEGER, | |
39f19ebb AS |
512 | .arg1_type = ARG_PTR_TO_MEM, |
513 | .arg2_type = ARG_CONST_SIZE, | |
9c959c86 AS |
514 | }; |
515 | ||
0756ea3e AS |
516 | const struct bpf_func_proto *bpf_get_trace_printk_proto(void) |
517 | { | |
518 | /* | |
519 | * this program might be calling bpf_trace_printk, | |
520 | * so allocate per-cpu printk buffers | |
521 | */ | |
522 | trace_printk_init_buffers(); | |
523 | ||
524 | return &bpf_trace_printk_proto; | |
525 | } | |
526 | ||
492e639f YS |
527 | #define MAX_SEQ_PRINTF_VARARGS 12 |
528 | #define MAX_SEQ_PRINTF_MAX_MEMCPY 6 | |
529 | #define MAX_SEQ_PRINTF_STR_LEN 128 | |
530 | ||
531 | struct bpf_seq_printf_buf { | |
532 | char buf[MAX_SEQ_PRINTF_MAX_MEMCPY][MAX_SEQ_PRINTF_STR_LEN]; | |
533 | }; | |
534 | static DEFINE_PER_CPU(struct bpf_seq_printf_buf, bpf_seq_printf_buf); | |
535 | static DEFINE_PER_CPU(int, bpf_seq_printf_buf_used); | |
536 | ||
537 | BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size, | |
538 | const void *, data, u32, data_len) | |
539 | { | |
540 | int err = -EINVAL, fmt_cnt = 0, memcpy_cnt = 0; | |
541 | int i, buf_used, copy_size, num_args; | |
542 | u64 params[MAX_SEQ_PRINTF_VARARGS]; | |
543 | struct bpf_seq_printf_buf *bufs; | |
544 | const u64 *args = data; | |
545 | ||
546 | buf_used = this_cpu_inc_return(bpf_seq_printf_buf_used); | |
547 | if (WARN_ON_ONCE(buf_used > 1)) { | |
548 | err = -EBUSY; | |
549 | goto out; | |
550 | } | |
551 | ||
552 | bufs = this_cpu_ptr(&bpf_seq_printf_buf); | |
553 | ||
554 | /* | |
555 | * bpf_check()->check_func_arg()->check_stack_boundary() | |
556 | * guarantees that fmt points to bpf program stack, | |
557 | * fmt_size bytes of it were initialized and fmt_size > 0 | |
558 | */ | |
559 | if (fmt[--fmt_size] != 0) | |
560 | goto out; | |
561 | ||
562 | if (data_len & 7) | |
563 | goto out; | |
564 | ||
565 | for (i = 0; i < fmt_size; i++) { | |
566 | if (fmt[i] == '%') { | |
567 | if (fmt[i + 1] == '%') | |
568 | i++; | |
569 | else if (!data || !data_len) | |
570 | goto out; | |
571 | } | |
572 | } | |
573 | ||
574 | num_args = data_len / 8; | |
575 | ||
576 | /* check format string for allowed specifiers */ | |
577 | for (i = 0; i < fmt_size; i++) { | |
578 | /* only printable ascii for now. */ | |
579 | if ((!isprint(fmt[i]) && !isspace(fmt[i])) || !isascii(fmt[i])) { | |
580 | err = -EINVAL; | |
581 | goto out; | |
582 | } | |
583 | ||
584 | if (fmt[i] != '%') | |
585 | continue; | |
586 | ||
587 | if (fmt[i + 1] == '%') { | |
588 | i++; | |
589 | continue; | |
590 | } | |
591 | ||
592 | if (fmt_cnt >= MAX_SEQ_PRINTF_VARARGS) { | |
593 | err = -E2BIG; | |
594 | goto out; | |
595 | } | |
596 | ||
597 | if (fmt_cnt >= num_args) { | |
598 | err = -EINVAL; | |
599 | goto out; | |
600 | } | |
601 | ||
602 | /* fmt[i] != 0 && fmt[last] == 0, so we can access fmt[i + 1] */ | |
603 | i++; | |
604 | ||
605 | /* skip optional "[0 +-][num]" width formating field */ | |
606 | while (fmt[i] == '0' || fmt[i] == '+' || fmt[i] == '-' || | |
607 | fmt[i] == ' ') | |
608 | i++; | |
609 | if (fmt[i] >= '1' && fmt[i] <= '9') { | |
610 | i++; | |
611 | while (fmt[i] >= '0' && fmt[i] <= '9') | |
612 | i++; | |
613 | } | |
614 | ||
615 | if (fmt[i] == 's') { | |
19c8d8ac AM |
616 | void *unsafe_ptr; |
617 | ||
492e639f YS |
618 | /* try our best to copy */ |
619 | if (memcpy_cnt >= MAX_SEQ_PRINTF_MAX_MEMCPY) { | |
620 | err = -E2BIG; | |
621 | goto out; | |
622 | } | |
623 | ||
19c8d8ac AM |
624 | unsafe_ptr = (void *)(long)args[fmt_cnt]; |
625 | err = strncpy_from_kernel_nofault(bufs->buf[memcpy_cnt], | |
626 | unsafe_ptr, MAX_SEQ_PRINTF_STR_LEN); | |
492e639f YS |
627 | if (err < 0) |
628 | bufs->buf[memcpy_cnt][0] = '\0'; | |
629 | params[fmt_cnt] = (u64)(long)bufs->buf[memcpy_cnt]; | |
630 | ||
631 | fmt_cnt++; | |
632 | memcpy_cnt++; | |
633 | continue; | |
634 | } | |
635 | ||
636 | if (fmt[i] == 'p') { | |
637 | if (fmt[i + 1] == 0 || | |
638 | fmt[i + 1] == 'K' || | |
639 | fmt[i + 1] == 'x') { | |
640 | /* just kernel pointers */ | |
641 | params[fmt_cnt] = args[fmt_cnt]; | |
642 | fmt_cnt++; | |
643 | continue; | |
644 | } | |
645 | ||
646 | /* only support "%pI4", "%pi4", "%pI6" and "%pi6". */ | |
647 | if (fmt[i + 1] != 'i' && fmt[i + 1] != 'I') { | |
648 | err = -EINVAL; | |
649 | goto out; | |
650 | } | |
651 | if (fmt[i + 2] != '4' && fmt[i + 2] != '6') { | |
652 | err = -EINVAL; | |
653 | goto out; | |
654 | } | |
655 | ||
656 | if (memcpy_cnt >= MAX_SEQ_PRINTF_MAX_MEMCPY) { | |
657 | err = -E2BIG; | |
658 | goto out; | |
659 | } | |
660 | ||
661 | ||
662 | copy_size = (fmt[i + 2] == '4') ? 4 : 16; | |
663 | ||
fe557319 | 664 | err = copy_from_kernel_nofault(bufs->buf[memcpy_cnt], |
492e639f YS |
665 | (void *) (long) args[fmt_cnt], |
666 | copy_size); | |
667 | if (err < 0) | |
668 | memset(bufs->buf[memcpy_cnt], 0, copy_size); | |
669 | params[fmt_cnt] = (u64)(long)bufs->buf[memcpy_cnt]; | |
670 | ||
671 | i += 2; | |
672 | fmt_cnt++; | |
673 | memcpy_cnt++; | |
674 | continue; | |
675 | } | |
676 | ||
677 | if (fmt[i] == 'l') { | |
678 | i++; | |
679 | if (fmt[i] == 'l') | |
680 | i++; | |
681 | } | |
682 | ||
683 | if (fmt[i] != 'i' && fmt[i] != 'd' && | |
684 | fmt[i] != 'u' && fmt[i] != 'x') { | |
685 | err = -EINVAL; | |
686 | goto out; | |
687 | } | |
688 | ||
689 | params[fmt_cnt] = args[fmt_cnt]; | |
690 | fmt_cnt++; | |
691 | } | |
692 | ||
693 | /* Maximumly we can have MAX_SEQ_PRINTF_VARARGS parameter, just give | |
694 | * all of them to seq_printf(). | |
695 | */ | |
696 | seq_printf(m, fmt, params[0], params[1], params[2], params[3], | |
697 | params[4], params[5], params[6], params[7], params[8], | |
698 | params[9], params[10], params[11]); | |
699 | ||
700 | err = seq_has_overflowed(m) ? -EOVERFLOW : 0; | |
701 | out: | |
702 | this_cpu_dec(bpf_seq_printf_buf_used); | |
703 | return err; | |
704 | } | |
705 | ||
706 | static int bpf_seq_printf_btf_ids[5]; | |
707 | static const struct bpf_func_proto bpf_seq_printf_proto = { | |
708 | .func = bpf_seq_printf, | |
709 | .gpl_only = true, | |
710 | .ret_type = RET_INTEGER, | |
711 | .arg1_type = ARG_PTR_TO_BTF_ID, | |
712 | .arg2_type = ARG_PTR_TO_MEM, | |
713 | .arg3_type = ARG_CONST_SIZE, | |
714 | .arg4_type = ARG_PTR_TO_MEM_OR_NULL, | |
715 | .arg5_type = ARG_CONST_SIZE_OR_ZERO, | |
716 | .btf_id = bpf_seq_printf_btf_ids, | |
717 | }; | |
718 | ||
719 | BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len) | |
720 | { | |
721 | return seq_write(m, data, len) ? -EOVERFLOW : 0; | |
722 | } | |
723 | ||
724 | static int bpf_seq_write_btf_ids[5]; | |
725 | static const struct bpf_func_proto bpf_seq_write_proto = { | |
726 | .func = bpf_seq_write, | |
727 | .gpl_only = true, | |
728 | .ret_type = RET_INTEGER, | |
729 | .arg1_type = ARG_PTR_TO_BTF_ID, | |
730 | .arg2_type = ARG_PTR_TO_MEM, | |
731 | .arg3_type = ARG_CONST_SIZE_OR_ZERO, | |
732 | .btf_id = bpf_seq_write_btf_ids, | |
733 | }; | |
734 | ||
908432ca YS |
735 | static __always_inline int |
736 | get_map_perf_counter(struct bpf_map *map, u64 flags, | |
737 | u64 *value, u64 *enabled, u64 *running) | |
35578d79 | 738 | { |
35578d79 | 739 | struct bpf_array *array = container_of(map, struct bpf_array, map); |
6816a7ff DB |
740 | unsigned int cpu = smp_processor_id(); |
741 | u64 index = flags & BPF_F_INDEX_MASK; | |
3b1efb19 | 742 | struct bpf_event_entry *ee; |
35578d79 | 743 | |
6816a7ff DB |
744 | if (unlikely(flags & ~(BPF_F_INDEX_MASK))) |
745 | return -EINVAL; | |
746 | if (index == BPF_F_CURRENT_CPU) | |
747 | index = cpu; | |
35578d79 KX |
748 | if (unlikely(index >= array->map.max_entries)) |
749 | return -E2BIG; | |
750 | ||
3b1efb19 | 751 | ee = READ_ONCE(array->ptrs[index]); |
1ca1cc98 | 752 | if (!ee) |
35578d79 KX |
753 | return -ENOENT; |
754 | ||
908432ca YS |
755 | return perf_event_read_local(ee->event, value, enabled, running); |
756 | } | |
757 | ||
758 | BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags) | |
759 | { | |
760 | u64 value = 0; | |
761 | int err; | |
762 | ||
763 | err = get_map_perf_counter(map, flags, &value, NULL, NULL); | |
35578d79 | 764 | /* |
f91840a3 AS |
765 | * this api is ugly since we miss [-22..-2] range of valid |
766 | * counter values, but that's uapi | |
35578d79 | 767 | */ |
f91840a3 AS |
768 | if (err) |
769 | return err; | |
770 | return value; | |
35578d79 KX |
771 | } |
772 | ||
62544ce8 | 773 | static const struct bpf_func_proto bpf_perf_event_read_proto = { |
35578d79 | 774 | .func = bpf_perf_event_read, |
1075ef59 | 775 | .gpl_only = true, |
35578d79 KX |
776 | .ret_type = RET_INTEGER, |
777 | .arg1_type = ARG_CONST_MAP_PTR, | |
778 | .arg2_type = ARG_ANYTHING, | |
779 | }; | |
780 | ||
908432ca YS |
781 | BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags, |
782 | struct bpf_perf_event_value *, buf, u32, size) | |
783 | { | |
784 | int err = -EINVAL; | |
785 | ||
786 | if (unlikely(size != sizeof(struct bpf_perf_event_value))) | |
787 | goto clear; | |
788 | err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled, | |
789 | &buf->running); | |
790 | if (unlikely(err)) | |
791 | goto clear; | |
792 | return 0; | |
793 | clear: | |
794 | memset(buf, 0, size); | |
795 | return err; | |
796 | } | |
797 | ||
798 | static const struct bpf_func_proto bpf_perf_event_read_value_proto = { | |
799 | .func = bpf_perf_event_read_value, | |
800 | .gpl_only = true, | |
801 | .ret_type = RET_INTEGER, | |
802 | .arg1_type = ARG_CONST_MAP_PTR, | |
803 | .arg2_type = ARG_ANYTHING, | |
804 | .arg3_type = ARG_PTR_TO_UNINIT_MEM, | |
805 | .arg4_type = ARG_CONST_SIZE, | |
806 | }; | |
807 | ||
8e7a3920 DB |
808 | static __always_inline u64 |
809 | __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map, | |
283ca526 | 810 | u64 flags, struct perf_sample_data *sd) |
a43eec30 | 811 | { |
a43eec30 | 812 | struct bpf_array *array = container_of(map, struct bpf_array, map); |
d7931330 | 813 | unsigned int cpu = smp_processor_id(); |
1e33759c | 814 | u64 index = flags & BPF_F_INDEX_MASK; |
3b1efb19 | 815 | struct bpf_event_entry *ee; |
a43eec30 | 816 | struct perf_event *event; |
a43eec30 | 817 | |
1e33759c | 818 | if (index == BPF_F_CURRENT_CPU) |
d7931330 | 819 | index = cpu; |
a43eec30 AS |
820 | if (unlikely(index >= array->map.max_entries)) |
821 | return -E2BIG; | |
822 | ||
3b1efb19 | 823 | ee = READ_ONCE(array->ptrs[index]); |
1ca1cc98 | 824 | if (!ee) |
a43eec30 AS |
825 | return -ENOENT; |
826 | ||
3b1efb19 | 827 | event = ee->event; |
a43eec30 AS |
828 | if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE || |
829 | event->attr.config != PERF_COUNT_SW_BPF_OUTPUT)) | |
830 | return -EINVAL; | |
831 | ||
d7931330 | 832 | if (unlikely(event->oncpu != cpu)) |
a43eec30 AS |
833 | return -EOPNOTSUPP; |
834 | ||
56201969 | 835 | return perf_event_output(event, sd, regs); |
a43eec30 AS |
836 | } |
837 | ||
9594dc3c MM |
838 | /* |
839 | * Support executing tracepoints in normal, irq, and nmi context that each call | |
840 | * bpf_perf_event_output | |
841 | */ | |
842 | struct bpf_trace_sample_data { | |
843 | struct perf_sample_data sds[3]; | |
844 | }; | |
845 | ||
846 | static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_trace_sds); | |
847 | static DEFINE_PER_CPU(int, bpf_trace_nest_level); | |
f3694e00 DB |
848 | BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map, |
849 | u64, flags, void *, data, u64, size) | |
8e7a3920 | 850 | { |
9594dc3c MM |
851 | struct bpf_trace_sample_data *sds = this_cpu_ptr(&bpf_trace_sds); |
852 | int nest_level = this_cpu_inc_return(bpf_trace_nest_level); | |
8e7a3920 DB |
853 | struct perf_raw_record raw = { |
854 | .frag = { | |
855 | .size = size, | |
856 | .data = data, | |
857 | }, | |
858 | }; | |
9594dc3c MM |
859 | struct perf_sample_data *sd; |
860 | int err; | |
8e7a3920 | 861 | |
9594dc3c MM |
862 | if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(sds->sds))) { |
863 | err = -EBUSY; | |
864 | goto out; | |
865 | } | |
866 | ||
867 | sd = &sds->sds[nest_level - 1]; | |
868 | ||
869 | if (unlikely(flags & ~(BPF_F_INDEX_MASK))) { | |
870 | err = -EINVAL; | |
871 | goto out; | |
872 | } | |
8e7a3920 | 873 | |
283ca526 DB |
874 | perf_sample_data_init(sd, 0, 0); |
875 | sd->raw = &raw; | |
876 | ||
9594dc3c MM |
877 | err = __bpf_perf_event_output(regs, map, flags, sd); |
878 | ||
879 | out: | |
880 | this_cpu_dec(bpf_trace_nest_level); | |
881 | return err; | |
8e7a3920 DB |
882 | } |
883 | ||
a43eec30 AS |
884 | static const struct bpf_func_proto bpf_perf_event_output_proto = { |
885 | .func = bpf_perf_event_output, | |
1075ef59 | 886 | .gpl_only = true, |
a43eec30 AS |
887 | .ret_type = RET_INTEGER, |
888 | .arg1_type = ARG_PTR_TO_CTX, | |
889 | .arg2_type = ARG_CONST_MAP_PTR, | |
890 | .arg3_type = ARG_ANYTHING, | |
39f19ebb | 891 | .arg4_type = ARG_PTR_TO_MEM, |
a60dd35d | 892 | .arg5_type = ARG_CONST_SIZE_OR_ZERO, |
a43eec30 AS |
893 | }; |
894 | ||
768fb61f AZ |
895 | static DEFINE_PER_CPU(int, bpf_event_output_nest_level); |
896 | struct bpf_nested_pt_regs { | |
897 | struct pt_regs regs[3]; | |
898 | }; | |
899 | static DEFINE_PER_CPU(struct bpf_nested_pt_regs, bpf_pt_regs); | |
900 | static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_misc_sds); | |
bd570ff9 | 901 | |
555c8a86 DB |
902 | u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size, |
903 | void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy) | |
bd570ff9 | 904 | { |
768fb61f | 905 | int nest_level = this_cpu_inc_return(bpf_event_output_nest_level); |
555c8a86 DB |
906 | struct perf_raw_frag frag = { |
907 | .copy = ctx_copy, | |
908 | .size = ctx_size, | |
909 | .data = ctx, | |
910 | }; | |
911 | struct perf_raw_record raw = { | |
912 | .frag = { | |
183fc153 AM |
913 | { |
914 | .next = ctx_size ? &frag : NULL, | |
915 | }, | |
555c8a86 DB |
916 | .size = meta_size, |
917 | .data = meta, | |
918 | }, | |
919 | }; | |
768fb61f AZ |
920 | struct perf_sample_data *sd; |
921 | struct pt_regs *regs; | |
922 | u64 ret; | |
923 | ||
924 | if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bpf_misc_sds.sds))) { | |
925 | ret = -EBUSY; | |
926 | goto out; | |
927 | } | |
928 | sd = this_cpu_ptr(&bpf_misc_sds.sds[nest_level - 1]); | |
929 | regs = this_cpu_ptr(&bpf_pt_regs.regs[nest_level - 1]); | |
bd570ff9 DB |
930 | |
931 | perf_fetch_caller_regs(regs); | |
283ca526 DB |
932 | perf_sample_data_init(sd, 0, 0); |
933 | sd->raw = &raw; | |
bd570ff9 | 934 | |
768fb61f AZ |
935 | ret = __bpf_perf_event_output(regs, map, flags, sd); |
936 | out: | |
937 | this_cpu_dec(bpf_event_output_nest_level); | |
938 | return ret; | |
bd570ff9 DB |
939 | } |
940 | ||
f3694e00 | 941 | BPF_CALL_0(bpf_get_current_task) |
606274c5 AS |
942 | { |
943 | return (long) current; | |
944 | } | |
945 | ||
f470378c | 946 | const struct bpf_func_proto bpf_get_current_task_proto = { |
606274c5 AS |
947 | .func = bpf_get_current_task, |
948 | .gpl_only = true, | |
949 | .ret_type = RET_INTEGER, | |
950 | }; | |
951 | ||
f3694e00 | 952 | BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx) |
60d20f91 | 953 | { |
60d20f91 SD |
954 | struct bpf_array *array = container_of(map, struct bpf_array, map); |
955 | struct cgroup *cgrp; | |
60d20f91 | 956 | |
60d20f91 SD |
957 | if (unlikely(idx >= array->map.max_entries)) |
958 | return -E2BIG; | |
959 | ||
960 | cgrp = READ_ONCE(array->ptrs[idx]); | |
961 | if (unlikely(!cgrp)) | |
962 | return -EAGAIN; | |
963 | ||
964 | return task_under_cgroup_hierarchy(current, cgrp); | |
965 | } | |
966 | ||
967 | static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = { | |
968 | .func = bpf_current_task_under_cgroup, | |
969 | .gpl_only = false, | |
970 | .ret_type = RET_INTEGER, | |
971 | .arg1_type = ARG_CONST_MAP_PTR, | |
972 | .arg2_type = ARG_ANYTHING, | |
973 | }; | |
974 | ||
8b401f9e YS |
975 | struct send_signal_irq_work { |
976 | struct irq_work irq_work; | |
977 | struct task_struct *task; | |
978 | u32 sig; | |
8482941f | 979 | enum pid_type type; |
8b401f9e YS |
980 | }; |
981 | ||
982 | static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work); | |
983 | ||
984 | static void do_bpf_send_signal(struct irq_work *entry) | |
985 | { | |
986 | struct send_signal_irq_work *work; | |
987 | ||
988 | work = container_of(entry, struct send_signal_irq_work, irq_work); | |
8482941f | 989 | group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type); |
8b401f9e YS |
990 | } |
991 | ||
8482941f | 992 | static int bpf_send_signal_common(u32 sig, enum pid_type type) |
8b401f9e YS |
993 | { |
994 | struct send_signal_irq_work *work = NULL; | |
995 | ||
996 | /* Similar to bpf_probe_write_user, task needs to be | |
997 | * in a sound condition and kernel memory access be | |
998 | * permitted in order to send signal to the current | |
999 | * task. | |
1000 | */ | |
1001 | if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING))) | |
1002 | return -EPERM; | |
1003 | if (unlikely(uaccess_kernel())) | |
1004 | return -EPERM; | |
1005 | if (unlikely(!nmi_uaccess_okay())) | |
1006 | return -EPERM; | |
1007 | ||
1bc7896e | 1008 | if (irqs_disabled()) { |
e1afb702 YS |
1009 | /* Do an early check on signal validity. Otherwise, |
1010 | * the error is lost in deferred irq_work. | |
1011 | */ | |
1012 | if (unlikely(!valid_signal(sig))) | |
1013 | return -EINVAL; | |
1014 | ||
8b401f9e | 1015 | work = this_cpu_ptr(&send_signal_work); |
153bedba | 1016 | if (atomic_read(&work->irq_work.flags) & IRQ_WORK_BUSY) |
8b401f9e YS |
1017 | return -EBUSY; |
1018 | ||
1019 | /* Add the current task, which is the target of sending signal, | |
1020 | * to the irq_work. The current task may change when queued | |
1021 | * irq works get executed. | |
1022 | */ | |
1023 | work->task = current; | |
1024 | work->sig = sig; | |
8482941f | 1025 | work->type = type; |
8b401f9e YS |
1026 | irq_work_queue(&work->irq_work); |
1027 | return 0; | |
1028 | } | |
1029 | ||
8482941f YS |
1030 | return group_send_sig_info(sig, SEND_SIG_PRIV, current, type); |
1031 | } | |
1032 | ||
1033 | BPF_CALL_1(bpf_send_signal, u32, sig) | |
1034 | { | |
1035 | return bpf_send_signal_common(sig, PIDTYPE_TGID); | |
8b401f9e YS |
1036 | } |
1037 | ||
1038 | static const struct bpf_func_proto bpf_send_signal_proto = { | |
1039 | .func = bpf_send_signal, | |
1040 | .gpl_only = false, | |
1041 | .ret_type = RET_INTEGER, | |
1042 | .arg1_type = ARG_ANYTHING, | |
1043 | }; | |
1044 | ||
8482941f YS |
1045 | BPF_CALL_1(bpf_send_signal_thread, u32, sig) |
1046 | { | |
1047 | return bpf_send_signal_common(sig, PIDTYPE_PID); | |
1048 | } | |
1049 | ||
1050 | static const struct bpf_func_proto bpf_send_signal_thread_proto = { | |
1051 | .func = bpf_send_signal_thread, | |
1052 | .gpl_only = false, | |
1053 | .ret_type = RET_INTEGER, | |
1054 | .arg1_type = ARG_ANYTHING, | |
1055 | }; | |
1056 | ||
fc611f47 KS |
1057 | const struct bpf_func_proto * |
1058 | bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) | |
2541517c AS |
1059 | { |
1060 | switch (func_id) { | |
1061 | case BPF_FUNC_map_lookup_elem: | |
1062 | return &bpf_map_lookup_elem_proto; | |
1063 | case BPF_FUNC_map_update_elem: | |
1064 | return &bpf_map_update_elem_proto; | |
1065 | case BPF_FUNC_map_delete_elem: | |
1066 | return &bpf_map_delete_elem_proto; | |
02a8c817 AC |
1067 | case BPF_FUNC_map_push_elem: |
1068 | return &bpf_map_push_elem_proto; | |
1069 | case BPF_FUNC_map_pop_elem: | |
1070 | return &bpf_map_pop_elem_proto; | |
1071 | case BPF_FUNC_map_peek_elem: | |
1072 | return &bpf_map_peek_elem_proto; | |
d9847d31 AS |
1073 | case BPF_FUNC_ktime_get_ns: |
1074 | return &bpf_ktime_get_ns_proto; | |
71d19214 MÅ» |
1075 | case BPF_FUNC_ktime_get_boot_ns: |
1076 | return &bpf_ktime_get_boot_ns_proto; | |
04fd61ab AS |
1077 | case BPF_FUNC_tail_call: |
1078 | return &bpf_tail_call_proto; | |
ffeedafb AS |
1079 | case BPF_FUNC_get_current_pid_tgid: |
1080 | return &bpf_get_current_pid_tgid_proto; | |
606274c5 AS |
1081 | case BPF_FUNC_get_current_task: |
1082 | return &bpf_get_current_task_proto; | |
ffeedafb AS |
1083 | case BPF_FUNC_get_current_uid_gid: |
1084 | return &bpf_get_current_uid_gid_proto; | |
1085 | case BPF_FUNC_get_current_comm: | |
1086 | return &bpf_get_current_comm_proto; | |
9c959c86 | 1087 | case BPF_FUNC_trace_printk: |
0756ea3e | 1088 | return bpf_get_trace_printk_proto(); |
ab1973d3 AS |
1089 | case BPF_FUNC_get_smp_processor_id: |
1090 | return &bpf_get_smp_processor_id_proto; | |
2d0e30c3 DB |
1091 | case BPF_FUNC_get_numa_node_id: |
1092 | return &bpf_get_numa_node_id_proto; | |
35578d79 KX |
1093 | case BPF_FUNC_perf_event_read: |
1094 | return &bpf_perf_event_read_proto; | |
96ae5227 SD |
1095 | case BPF_FUNC_probe_write_user: |
1096 | return bpf_get_probe_write_proto(); | |
60d20f91 SD |
1097 | case BPF_FUNC_current_task_under_cgroup: |
1098 | return &bpf_current_task_under_cgroup_proto; | |
8937bd80 AS |
1099 | case BPF_FUNC_get_prandom_u32: |
1100 | return &bpf_get_prandom_u32_proto; | |
6ae08ae3 DB |
1101 | case BPF_FUNC_probe_read_user: |
1102 | return &bpf_probe_read_user_proto; | |
1103 | case BPF_FUNC_probe_read_kernel: | |
1104 | return &bpf_probe_read_kernel_proto; | |
6ae08ae3 DB |
1105 | case BPF_FUNC_probe_read_user_str: |
1106 | return &bpf_probe_read_user_str_proto; | |
1107 | case BPF_FUNC_probe_read_kernel_str: | |
1108 | return &bpf_probe_read_kernel_str_proto; | |
0ebeea8c DB |
1109 | #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE |
1110 | case BPF_FUNC_probe_read: | |
1111 | return &bpf_probe_read_compat_proto; | |
a5e8c070 | 1112 | case BPF_FUNC_probe_read_str: |
6ae08ae3 | 1113 | return &bpf_probe_read_compat_str_proto; |
0ebeea8c | 1114 | #endif |
34ea38ca | 1115 | #ifdef CONFIG_CGROUPS |
bf6fa2c8 YS |
1116 | case BPF_FUNC_get_current_cgroup_id: |
1117 | return &bpf_get_current_cgroup_id_proto; | |
34ea38ca | 1118 | #endif |
8b401f9e YS |
1119 | case BPF_FUNC_send_signal: |
1120 | return &bpf_send_signal_proto; | |
8482941f YS |
1121 | case BPF_FUNC_send_signal_thread: |
1122 | return &bpf_send_signal_thread_proto; | |
b80b033b SL |
1123 | case BPF_FUNC_perf_event_read_value: |
1124 | return &bpf_perf_event_read_value_proto; | |
b4490c5c CN |
1125 | case BPF_FUNC_get_ns_current_pid_tgid: |
1126 | return &bpf_get_ns_current_pid_tgid_proto; | |
457f4436 AN |
1127 | case BPF_FUNC_ringbuf_output: |
1128 | return &bpf_ringbuf_output_proto; | |
1129 | case BPF_FUNC_ringbuf_reserve: | |
1130 | return &bpf_ringbuf_reserve_proto; | |
1131 | case BPF_FUNC_ringbuf_submit: | |
1132 | return &bpf_ringbuf_submit_proto; | |
1133 | case BPF_FUNC_ringbuf_discard: | |
1134 | return &bpf_ringbuf_discard_proto; | |
1135 | case BPF_FUNC_ringbuf_query: | |
1136 | return &bpf_ringbuf_query_proto; | |
9fd82b61 AS |
1137 | default: |
1138 | return NULL; | |
1139 | } | |
1140 | } | |
1141 | ||
5e43f899 AI |
1142 | static const struct bpf_func_proto * |
1143 | kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) | |
9fd82b61 AS |
1144 | { |
1145 | switch (func_id) { | |
a43eec30 AS |
1146 | case BPF_FUNC_perf_event_output: |
1147 | return &bpf_perf_event_output_proto; | |
d5a3b1f6 AS |
1148 | case BPF_FUNC_get_stackid: |
1149 | return &bpf_get_stackid_proto; | |
c195651e YS |
1150 | case BPF_FUNC_get_stack: |
1151 | return &bpf_get_stack_proto; | |
9802d865 JB |
1152 | #ifdef CONFIG_BPF_KPROBE_OVERRIDE |
1153 | case BPF_FUNC_override_return: | |
1154 | return &bpf_override_return_proto; | |
1155 | #endif | |
2541517c | 1156 | default: |
fc611f47 | 1157 | return bpf_tracing_func_proto(func_id, prog); |
2541517c AS |
1158 | } |
1159 | } | |
1160 | ||
1161 | /* bpf+kprobe programs can access fields of 'struct pt_regs' */ | |
19de99f7 | 1162 | static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type, |
5e43f899 | 1163 | const struct bpf_prog *prog, |
23994631 | 1164 | struct bpf_insn_access_aux *info) |
2541517c | 1165 | { |
2541517c AS |
1166 | if (off < 0 || off >= sizeof(struct pt_regs)) |
1167 | return false; | |
2541517c AS |
1168 | if (type != BPF_READ) |
1169 | return false; | |
2541517c AS |
1170 | if (off % size != 0) |
1171 | return false; | |
2d071c64 DB |
1172 | /* |
1173 | * Assertion for 32 bit to make sure last 8 byte access | |
1174 | * (BPF_DW) to the last 4 byte member is disallowed. | |
1175 | */ | |
1176 | if (off + size > sizeof(struct pt_regs)) | |
1177 | return false; | |
1178 | ||
2541517c AS |
1179 | return true; |
1180 | } | |
1181 | ||
7de16e3a | 1182 | const struct bpf_verifier_ops kprobe_verifier_ops = { |
2541517c AS |
1183 | .get_func_proto = kprobe_prog_func_proto, |
1184 | .is_valid_access = kprobe_prog_is_valid_access, | |
1185 | }; | |
1186 | ||
7de16e3a JK |
1187 | const struct bpf_prog_ops kprobe_prog_ops = { |
1188 | }; | |
1189 | ||
f3694e00 DB |
1190 | BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map, |
1191 | u64, flags, void *, data, u64, size) | |
9940d67c | 1192 | { |
f3694e00 DB |
1193 | struct pt_regs *regs = *(struct pt_regs **)tp_buff; |
1194 | ||
9940d67c AS |
1195 | /* |
1196 | * r1 points to perf tracepoint buffer where first 8 bytes are hidden | |
1197 | * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it | |
f3694e00 | 1198 | * from there and call the same bpf_perf_event_output() helper inline. |
9940d67c | 1199 | */ |
f3694e00 | 1200 | return ____bpf_perf_event_output(regs, map, flags, data, size); |
9940d67c AS |
1201 | } |
1202 | ||
1203 | static const struct bpf_func_proto bpf_perf_event_output_proto_tp = { | |
1204 | .func = bpf_perf_event_output_tp, | |
1205 | .gpl_only = true, | |
1206 | .ret_type = RET_INTEGER, | |
1207 | .arg1_type = ARG_PTR_TO_CTX, | |
1208 | .arg2_type = ARG_CONST_MAP_PTR, | |
1209 | .arg3_type = ARG_ANYTHING, | |
39f19ebb | 1210 | .arg4_type = ARG_PTR_TO_MEM, |
a60dd35d | 1211 | .arg5_type = ARG_CONST_SIZE_OR_ZERO, |
9940d67c AS |
1212 | }; |
1213 | ||
f3694e00 DB |
1214 | BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map, |
1215 | u64, flags) | |
9940d67c | 1216 | { |
f3694e00 | 1217 | struct pt_regs *regs = *(struct pt_regs **)tp_buff; |
9940d67c | 1218 | |
f3694e00 DB |
1219 | /* |
1220 | * Same comment as in bpf_perf_event_output_tp(), only that this time | |
1221 | * the other helper's function body cannot be inlined due to being | |
1222 | * external, thus we need to call raw helper function. | |
1223 | */ | |
1224 | return bpf_get_stackid((unsigned long) regs, (unsigned long) map, | |
1225 | flags, 0, 0); | |
9940d67c AS |
1226 | } |
1227 | ||
1228 | static const struct bpf_func_proto bpf_get_stackid_proto_tp = { | |
1229 | .func = bpf_get_stackid_tp, | |
1230 | .gpl_only = true, | |
1231 | .ret_type = RET_INTEGER, | |
1232 | .arg1_type = ARG_PTR_TO_CTX, | |
1233 | .arg2_type = ARG_CONST_MAP_PTR, | |
1234 | .arg3_type = ARG_ANYTHING, | |
1235 | }; | |
1236 | ||
c195651e YS |
1237 | BPF_CALL_4(bpf_get_stack_tp, void *, tp_buff, void *, buf, u32, size, |
1238 | u64, flags) | |
1239 | { | |
1240 | struct pt_regs *regs = *(struct pt_regs **)tp_buff; | |
1241 | ||
1242 | return bpf_get_stack((unsigned long) regs, (unsigned long) buf, | |
1243 | (unsigned long) size, flags, 0); | |
1244 | } | |
1245 | ||
1246 | static const struct bpf_func_proto bpf_get_stack_proto_tp = { | |
1247 | .func = bpf_get_stack_tp, | |
1248 | .gpl_only = true, | |
1249 | .ret_type = RET_INTEGER, | |
1250 | .arg1_type = ARG_PTR_TO_CTX, | |
1251 | .arg2_type = ARG_PTR_TO_UNINIT_MEM, | |
1252 | .arg3_type = ARG_CONST_SIZE_OR_ZERO, | |
1253 | .arg4_type = ARG_ANYTHING, | |
1254 | }; | |
1255 | ||
5e43f899 AI |
1256 | static const struct bpf_func_proto * |
1257 | tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) | |
f005afed YS |
1258 | { |
1259 | switch (func_id) { | |
1260 | case BPF_FUNC_perf_event_output: | |
1261 | return &bpf_perf_event_output_proto_tp; | |
1262 | case BPF_FUNC_get_stackid: | |
1263 | return &bpf_get_stackid_proto_tp; | |
c195651e YS |
1264 | case BPF_FUNC_get_stack: |
1265 | return &bpf_get_stack_proto_tp; | |
f005afed | 1266 | default: |
fc611f47 | 1267 | return bpf_tracing_func_proto(func_id, prog); |
f005afed YS |
1268 | } |
1269 | } | |
1270 | ||
1271 | static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type, | |
5e43f899 | 1272 | const struct bpf_prog *prog, |
f005afed YS |
1273 | struct bpf_insn_access_aux *info) |
1274 | { | |
1275 | if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE) | |
1276 | return false; | |
1277 | if (type != BPF_READ) | |
1278 | return false; | |
1279 | if (off % size != 0) | |
1280 | return false; | |
1281 | ||
1282 | BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64)); | |
1283 | return true; | |
1284 | } | |
1285 | ||
1286 | const struct bpf_verifier_ops tracepoint_verifier_ops = { | |
1287 | .get_func_proto = tp_prog_func_proto, | |
1288 | .is_valid_access = tp_prog_is_valid_access, | |
1289 | }; | |
1290 | ||
1291 | const struct bpf_prog_ops tracepoint_prog_ops = { | |
1292 | }; | |
1293 | ||
1294 | BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx, | |
4bebdc7a YS |
1295 | struct bpf_perf_event_value *, buf, u32, size) |
1296 | { | |
1297 | int err = -EINVAL; | |
1298 | ||
1299 | if (unlikely(size != sizeof(struct bpf_perf_event_value))) | |
1300 | goto clear; | |
1301 | err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled, | |
1302 | &buf->running); | |
1303 | if (unlikely(err)) | |
1304 | goto clear; | |
1305 | return 0; | |
1306 | clear: | |
1307 | memset(buf, 0, size); | |
1308 | return err; | |
1309 | } | |
1310 | ||
f005afed YS |
1311 | static const struct bpf_func_proto bpf_perf_prog_read_value_proto = { |
1312 | .func = bpf_perf_prog_read_value, | |
4bebdc7a YS |
1313 | .gpl_only = true, |
1314 | .ret_type = RET_INTEGER, | |
1315 | .arg1_type = ARG_PTR_TO_CTX, | |
1316 | .arg2_type = ARG_PTR_TO_UNINIT_MEM, | |
1317 | .arg3_type = ARG_CONST_SIZE, | |
1318 | }; | |
1319 | ||
fff7b643 DX |
1320 | BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx, |
1321 | void *, buf, u32, size, u64, flags) | |
1322 | { | |
1323 | #ifndef CONFIG_X86 | |
1324 | return -ENOENT; | |
1325 | #else | |
1326 | static const u32 br_entry_size = sizeof(struct perf_branch_entry); | |
1327 | struct perf_branch_stack *br_stack = ctx->data->br_stack; | |
1328 | u32 to_copy; | |
1329 | ||
1330 | if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE)) | |
1331 | return -EINVAL; | |
1332 | ||
1333 | if (unlikely(!br_stack)) | |
1334 | return -EINVAL; | |
1335 | ||
1336 | if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE) | |
1337 | return br_stack->nr * br_entry_size; | |
1338 | ||
1339 | if (!buf || (size % br_entry_size != 0)) | |
1340 | return -EINVAL; | |
1341 | ||
1342 | to_copy = min_t(u32, br_stack->nr * br_entry_size, size); | |
1343 | memcpy(buf, br_stack->entries, to_copy); | |
1344 | ||
1345 | return to_copy; | |
1346 | #endif | |
1347 | } | |
1348 | ||
1349 | static const struct bpf_func_proto bpf_read_branch_records_proto = { | |
1350 | .func = bpf_read_branch_records, | |
1351 | .gpl_only = true, | |
1352 | .ret_type = RET_INTEGER, | |
1353 | .arg1_type = ARG_PTR_TO_CTX, | |
1354 | .arg2_type = ARG_PTR_TO_MEM_OR_NULL, | |
1355 | .arg3_type = ARG_CONST_SIZE_OR_ZERO, | |
1356 | .arg4_type = ARG_ANYTHING, | |
1357 | }; | |
1358 | ||
5e43f899 AI |
1359 | static const struct bpf_func_proto * |
1360 | pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) | |
9fd82b61 AS |
1361 | { |
1362 | switch (func_id) { | |
1363 | case BPF_FUNC_perf_event_output: | |
9940d67c | 1364 | return &bpf_perf_event_output_proto_tp; |
9fd82b61 | 1365 | case BPF_FUNC_get_stackid: |
9940d67c | 1366 | return &bpf_get_stackid_proto_tp; |
c195651e YS |
1367 | case BPF_FUNC_get_stack: |
1368 | return &bpf_get_stack_proto_tp; | |
4bebdc7a | 1369 | case BPF_FUNC_perf_prog_read_value: |
f005afed | 1370 | return &bpf_perf_prog_read_value_proto; |
fff7b643 DX |
1371 | case BPF_FUNC_read_branch_records: |
1372 | return &bpf_read_branch_records_proto; | |
9fd82b61 | 1373 | default: |
fc611f47 | 1374 | return bpf_tracing_func_proto(func_id, prog); |
9fd82b61 AS |
1375 | } |
1376 | } | |
1377 | ||
c4f6699d AS |
1378 | /* |
1379 | * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp | |
1380 | * to avoid potential recursive reuse issue when/if tracepoints are added | |
9594dc3c MM |
1381 | * inside bpf_*_event_output, bpf_get_stackid and/or bpf_get_stack. |
1382 | * | |
1383 | * Since raw tracepoints run despite bpf_prog_active, support concurrent usage | |
1384 | * in normal, irq, and nmi context. | |
c4f6699d | 1385 | */ |
9594dc3c MM |
1386 | struct bpf_raw_tp_regs { |
1387 | struct pt_regs regs[3]; | |
1388 | }; | |
1389 | static DEFINE_PER_CPU(struct bpf_raw_tp_regs, bpf_raw_tp_regs); | |
1390 | static DEFINE_PER_CPU(int, bpf_raw_tp_nest_level); | |
1391 | static struct pt_regs *get_bpf_raw_tp_regs(void) | |
1392 | { | |
1393 | struct bpf_raw_tp_regs *tp_regs = this_cpu_ptr(&bpf_raw_tp_regs); | |
1394 | int nest_level = this_cpu_inc_return(bpf_raw_tp_nest_level); | |
1395 | ||
1396 | if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(tp_regs->regs))) { | |
1397 | this_cpu_dec(bpf_raw_tp_nest_level); | |
1398 | return ERR_PTR(-EBUSY); | |
1399 | } | |
1400 | ||
1401 | return &tp_regs->regs[nest_level - 1]; | |
1402 | } | |
1403 | ||
1404 | static void put_bpf_raw_tp_regs(void) | |
1405 | { | |
1406 | this_cpu_dec(bpf_raw_tp_nest_level); | |
1407 | } | |
1408 | ||
c4f6699d AS |
1409 | BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args, |
1410 | struct bpf_map *, map, u64, flags, void *, data, u64, size) | |
1411 | { | |
9594dc3c MM |
1412 | struct pt_regs *regs = get_bpf_raw_tp_regs(); |
1413 | int ret; | |
1414 | ||
1415 | if (IS_ERR(regs)) | |
1416 | return PTR_ERR(regs); | |
c4f6699d AS |
1417 | |
1418 | perf_fetch_caller_regs(regs); | |
9594dc3c MM |
1419 | ret = ____bpf_perf_event_output(regs, map, flags, data, size); |
1420 | ||
1421 | put_bpf_raw_tp_regs(); | |
1422 | return ret; | |
c4f6699d AS |
1423 | } |
1424 | ||
1425 | static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = { | |
1426 | .func = bpf_perf_event_output_raw_tp, | |
1427 | .gpl_only = true, | |
1428 | .ret_type = RET_INTEGER, | |
1429 | .arg1_type = ARG_PTR_TO_CTX, | |
1430 | .arg2_type = ARG_CONST_MAP_PTR, | |
1431 | .arg3_type = ARG_ANYTHING, | |
1432 | .arg4_type = ARG_PTR_TO_MEM, | |
1433 | .arg5_type = ARG_CONST_SIZE_OR_ZERO, | |
1434 | }; | |
1435 | ||
a7658e1a | 1436 | extern const struct bpf_func_proto bpf_skb_output_proto; |
d831ee84 | 1437 | extern const struct bpf_func_proto bpf_xdp_output_proto; |
a7658e1a | 1438 | |
c4f6699d AS |
1439 | BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args, |
1440 | struct bpf_map *, map, u64, flags) | |
1441 | { | |
9594dc3c MM |
1442 | struct pt_regs *regs = get_bpf_raw_tp_regs(); |
1443 | int ret; | |
1444 | ||
1445 | if (IS_ERR(regs)) | |
1446 | return PTR_ERR(regs); | |
c4f6699d AS |
1447 | |
1448 | perf_fetch_caller_regs(regs); | |
1449 | /* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */ | |
9594dc3c MM |
1450 | ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map, |
1451 | flags, 0, 0); | |
1452 | put_bpf_raw_tp_regs(); | |
1453 | return ret; | |
c4f6699d AS |
1454 | } |
1455 | ||
1456 | static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = { | |
1457 | .func = bpf_get_stackid_raw_tp, | |
1458 | .gpl_only = true, | |
1459 | .ret_type = RET_INTEGER, | |
1460 | .arg1_type = ARG_PTR_TO_CTX, | |
1461 | .arg2_type = ARG_CONST_MAP_PTR, | |
1462 | .arg3_type = ARG_ANYTHING, | |
1463 | }; | |
1464 | ||
c195651e YS |
1465 | BPF_CALL_4(bpf_get_stack_raw_tp, struct bpf_raw_tracepoint_args *, args, |
1466 | void *, buf, u32, size, u64, flags) | |
1467 | { | |
9594dc3c MM |
1468 | struct pt_regs *regs = get_bpf_raw_tp_regs(); |
1469 | int ret; | |
1470 | ||
1471 | if (IS_ERR(regs)) | |
1472 | return PTR_ERR(regs); | |
c195651e YS |
1473 | |
1474 | perf_fetch_caller_regs(regs); | |
9594dc3c MM |
1475 | ret = bpf_get_stack((unsigned long) regs, (unsigned long) buf, |
1476 | (unsigned long) size, flags, 0); | |
1477 | put_bpf_raw_tp_regs(); | |
1478 | return ret; | |
c195651e YS |
1479 | } |
1480 | ||
1481 | static const struct bpf_func_proto bpf_get_stack_proto_raw_tp = { | |
1482 | .func = bpf_get_stack_raw_tp, | |
1483 | .gpl_only = true, | |
1484 | .ret_type = RET_INTEGER, | |
1485 | .arg1_type = ARG_PTR_TO_CTX, | |
1486 | .arg2_type = ARG_PTR_TO_MEM, | |
1487 | .arg3_type = ARG_CONST_SIZE_OR_ZERO, | |
1488 | .arg4_type = ARG_ANYTHING, | |
1489 | }; | |
1490 | ||
5e43f899 AI |
1491 | static const struct bpf_func_proto * |
1492 | raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) | |
c4f6699d AS |
1493 | { |
1494 | switch (func_id) { | |
1495 | case BPF_FUNC_perf_event_output: | |
1496 | return &bpf_perf_event_output_proto_raw_tp; | |
1497 | case BPF_FUNC_get_stackid: | |
1498 | return &bpf_get_stackid_proto_raw_tp; | |
c195651e YS |
1499 | case BPF_FUNC_get_stack: |
1500 | return &bpf_get_stack_proto_raw_tp; | |
c4f6699d | 1501 | default: |
fc611f47 | 1502 | return bpf_tracing_func_proto(func_id, prog); |
c4f6699d AS |
1503 | } |
1504 | } | |
1505 | ||
958a3f2d | 1506 | const struct bpf_func_proto * |
f1b9509c AS |
1507 | tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) |
1508 | { | |
1509 | switch (func_id) { | |
1510 | #ifdef CONFIG_NET | |
1511 | case BPF_FUNC_skb_output: | |
1512 | return &bpf_skb_output_proto; | |
d831ee84 EC |
1513 | case BPF_FUNC_xdp_output: |
1514 | return &bpf_xdp_output_proto; | |
f1b9509c | 1515 | #endif |
492e639f YS |
1516 | case BPF_FUNC_seq_printf: |
1517 | return prog->expected_attach_type == BPF_TRACE_ITER ? | |
1518 | &bpf_seq_printf_proto : | |
1519 | NULL; | |
1520 | case BPF_FUNC_seq_write: | |
1521 | return prog->expected_attach_type == BPF_TRACE_ITER ? | |
1522 | &bpf_seq_write_proto : | |
1523 | NULL; | |
f1b9509c AS |
1524 | default: |
1525 | return raw_tp_prog_func_proto(func_id, prog); | |
1526 | } | |
1527 | } | |
1528 | ||
c4f6699d AS |
1529 | static bool raw_tp_prog_is_valid_access(int off, int size, |
1530 | enum bpf_access_type type, | |
5e43f899 | 1531 | const struct bpf_prog *prog, |
c4f6699d AS |
1532 | struct bpf_insn_access_aux *info) |
1533 | { | |
f1b9509c AS |
1534 | if (off < 0 || off >= sizeof(__u64) * MAX_BPF_FUNC_ARGS) |
1535 | return false; | |
1536 | if (type != BPF_READ) | |
1537 | return false; | |
1538 | if (off % size != 0) | |
1539 | return false; | |
1540 | return true; | |
1541 | } | |
1542 | ||
1543 | static bool tracing_prog_is_valid_access(int off, int size, | |
1544 | enum bpf_access_type type, | |
1545 | const struct bpf_prog *prog, | |
1546 | struct bpf_insn_access_aux *info) | |
1547 | { | |
1548 | if (off < 0 || off >= sizeof(__u64) * MAX_BPF_FUNC_ARGS) | |
c4f6699d AS |
1549 | return false; |
1550 | if (type != BPF_READ) | |
1551 | return false; | |
1552 | if (off % size != 0) | |
1553 | return false; | |
9e15db66 | 1554 | return btf_ctx_access(off, size, type, prog, info); |
c4f6699d AS |
1555 | } |
1556 | ||
3e7c67d9 KS |
1557 | int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog, |
1558 | const union bpf_attr *kattr, | |
1559 | union bpf_attr __user *uattr) | |
1560 | { | |
1561 | return -ENOTSUPP; | |
1562 | } | |
1563 | ||
c4f6699d AS |
1564 | const struct bpf_verifier_ops raw_tracepoint_verifier_ops = { |
1565 | .get_func_proto = raw_tp_prog_func_proto, | |
1566 | .is_valid_access = raw_tp_prog_is_valid_access, | |
1567 | }; | |
1568 | ||
1569 | const struct bpf_prog_ops raw_tracepoint_prog_ops = { | |
1570 | }; | |
1571 | ||
f1b9509c AS |
1572 | const struct bpf_verifier_ops tracing_verifier_ops = { |
1573 | .get_func_proto = tracing_prog_func_proto, | |
1574 | .is_valid_access = tracing_prog_is_valid_access, | |
1575 | }; | |
1576 | ||
1577 | const struct bpf_prog_ops tracing_prog_ops = { | |
da00d2f1 | 1578 | .test_run = bpf_prog_test_run_tracing, |
f1b9509c AS |
1579 | }; |
1580 | ||
9df1c28b MM |
1581 | static bool raw_tp_writable_prog_is_valid_access(int off, int size, |
1582 | enum bpf_access_type type, | |
1583 | const struct bpf_prog *prog, | |
1584 | struct bpf_insn_access_aux *info) | |
1585 | { | |
1586 | if (off == 0) { | |
1587 | if (size != sizeof(u64) || type != BPF_READ) | |
1588 | return false; | |
1589 | info->reg_type = PTR_TO_TP_BUFFER; | |
1590 | } | |
1591 | return raw_tp_prog_is_valid_access(off, size, type, prog, info); | |
1592 | } | |
1593 | ||
1594 | const struct bpf_verifier_ops raw_tracepoint_writable_verifier_ops = { | |
1595 | .get_func_proto = raw_tp_prog_func_proto, | |
1596 | .is_valid_access = raw_tp_writable_prog_is_valid_access, | |
1597 | }; | |
1598 | ||
1599 | const struct bpf_prog_ops raw_tracepoint_writable_prog_ops = { | |
1600 | }; | |
1601 | ||
0515e599 | 1602 | static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type, |
5e43f899 | 1603 | const struct bpf_prog *prog, |
23994631 | 1604 | struct bpf_insn_access_aux *info) |
0515e599 | 1605 | { |
95da0cdb | 1606 | const int size_u64 = sizeof(u64); |
31fd8581 | 1607 | |
0515e599 AS |
1608 | if (off < 0 || off >= sizeof(struct bpf_perf_event_data)) |
1609 | return false; | |
1610 | if (type != BPF_READ) | |
1611 | return false; | |
bc23105c DB |
1612 | if (off % size != 0) { |
1613 | if (sizeof(unsigned long) != 4) | |
1614 | return false; | |
1615 | if (size != 8) | |
1616 | return false; | |
1617 | if (off % size != 4) | |
1618 | return false; | |
1619 | } | |
31fd8581 | 1620 | |
f96da094 DB |
1621 | switch (off) { |
1622 | case bpf_ctx_range(struct bpf_perf_event_data, sample_period): | |
95da0cdb TQ |
1623 | bpf_ctx_record_field_size(info, size_u64); |
1624 | if (!bpf_ctx_narrow_access_ok(off, size, size_u64)) | |
1625 | return false; | |
1626 | break; | |
1627 | case bpf_ctx_range(struct bpf_perf_event_data, addr): | |
1628 | bpf_ctx_record_field_size(info, size_u64); | |
1629 | if (!bpf_ctx_narrow_access_ok(off, size, size_u64)) | |
23994631 | 1630 | return false; |
f96da094 DB |
1631 | break; |
1632 | default: | |
0515e599 AS |
1633 | if (size != sizeof(long)) |
1634 | return false; | |
1635 | } | |
f96da094 | 1636 | |
0515e599 AS |
1637 | return true; |
1638 | } | |
1639 | ||
6b8cc1d1 DB |
1640 | static u32 pe_prog_convert_ctx_access(enum bpf_access_type type, |
1641 | const struct bpf_insn *si, | |
0515e599 | 1642 | struct bpf_insn *insn_buf, |
f96da094 | 1643 | struct bpf_prog *prog, u32 *target_size) |
0515e599 AS |
1644 | { |
1645 | struct bpf_insn *insn = insn_buf; | |
1646 | ||
6b8cc1d1 | 1647 | switch (si->off) { |
0515e599 | 1648 | case offsetof(struct bpf_perf_event_data, sample_period): |
f035a515 | 1649 | *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern, |
6b8cc1d1 | 1650 | data), si->dst_reg, si->src_reg, |
0515e599 | 1651 | offsetof(struct bpf_perf_event_data_kern, data)); |
6b8cc1d1 | 1652 | *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg, |
f96da094 DB |
1653 | bpf_target_off(struct perf_sample_data, period, 8, |
1654 | target_size)); | |
0515e599 | 1655 | break; |
95da0cdb TQ |
1656 | case offsetof(struct bpf_perf_event_data, addr): |
1657 | *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern, | |
1658 | data), si->dst_reg, si->src_reg, | |
1659 | offsetof(struct bpf_perf_event_data_kern, data)); | |
1660 | *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg, | |
1661 | bpf_target_off(struct perf_sample_data, addr, 8, | |
1662 | target_size)); | |
1663 | break; | |
0515e599 | 1664 | default: |
f035a515 | 1665 | *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern, |
6b8cc1d1 | 1666 | regs), si->dst_reg, si->src_reg, |
0515e599 | 1667 | offsetof(struct bpf_perf_event_data_kern, regs)); |
6b8cc1d1 DB |
1668 | *insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg, |
1669 | si->off); | |
0515e599 AS |
1670 | break; |
1671 | } | |
1672 | ||
1673 | return insn - insn_buf; | |
1674 | } | |
1675 | ||
7de16e3a | 1676 | const struct bpf_verifier_ops perf_event_verifier_ops = { |
f005afed | 1677 | .get_func_proto = pe_prog_func_proto, |
0515e599 AS |
1678 | .is_valid_access = pe_prog_is_valid_access, |
1679 | .convert_ctx_access = pe_prog_convert_ctx_access, | |
1680 | }; | |
7de16e3a JK |
1681 | |
1682 | const struct bpf_prog_ops perf_event_prog_ops = { | |
1683 | }; | |
e87c6bc3 YS |
1684 | |
1685 | static DEFINE_MUTEX(bpf_event_mutex); | |
1686 | ||
c8c088ba YS |
1687 | #define BPF_TRACE_MAX_PROGS 64 |
1688 | ||
e87c6bc3 YS |
1689 | int perf_event_attach_bpf_prog(struct perf_event *event, |
1690 | struct bpf_prog *prog) | |
1691 | { | |
e672db03 | 1692 | struct bpf_prog_array *old_array; |
e87c6bc3 YS |
1693 | struct bpf_prog_array *new_array; |
1694 | int ret = -EEXIST; | |
1695 | ||
9802d865 | 1696 | /* |
b4da3340 MH |
1697 | * Kprobe override only works if they are on the function entry, |
1698 | * and only if they are on the opt-in list. | |
9802d865 JB |
1699 | */ |
1700 | if (prog->kprobe_override && | |
b4da3340 | 1701 | (!trace_kprobe_on_func_entry(event->tp_event) || |
9802d865 JB |
1702 | !trace_kprobe_error_injectable(event->tp_event))) |
1703 | return -EINVAL; | |
1704 | ||
e87c6bc3 YS |
1705 | mutex_lock(&bpf_event_mutex); |
1706 | ||
1707 | if (event->prog) | |
07c41a29 | 1708 | goto unlock; |
e87c6bc3 | 1709 | |
e672db03 | 1710 | old_array = bpf_event_rcu_dereference(event->tp_event->prog_array); |
c8c088ba YS |
1711 | if (old_array && |
1712 | bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) { | |
1713 | ret = -E2BIG; | |
1714 | goto unlock; | |
1715 | } | |
1716 | ||
e87c6bc3 YS |
1717 | ret = bpf_prog_array_copy(old_array, NULL, prog, &new_array); |
1718 | if (ret < 0) | |
07c41a29 | 1719 | goto unlock; |
e87c6bc3 YS |
1720 | |
1721 | /* set the new array to event->tp_event and set event->prog */ | |
1722 | event->prog = prog; | |
1723 | rcu_assign_pointer(event->tp_event->prog_array, new_array); | |
1724 | bpf_prog_array_free(old_array); | |
1725 | ||
07c41a29 | 1726 | unlock: |
e87c6bc3 YS |
1727 | mutex_unlock(&bpf_event_mutex); |
1728 | return ret; | |
1729 | } | |
1730 | ||
1731 | void perf_event_detach_bpf_prog(struct perf_event *event) | |
1732 | { | |
e672db03 | 1733 | struct bpf_prog_array *old_array; |
e87c6bc3 YS |
1734 | struct bpf_prog_array *new_array; |
1735 | int ret; | |
1736 | ||
1737 | mutex_lock(&bpf_event_mutex); | |
1738 | ||
1739 | if (!event->prog) | |
07c41a29 | 1740 | goto unlock; |
e87c6bc3 | 1741 | |
e672db03 | 1742 | old_array = bpf_event_rcu_dereference(event->tp_event->prog_array); |
e87c6bc3 | 1743 | ret = bpf_prog_array_copy(old_array, event->prog, NULL, &new_array); |
170a7e3e SY |
1744 | if (ret == -ENOENT) |
1745 | goto unlock; | |
e87c6bc3 YS |
1746 | if (ret < 0) { |
1747 | bpf_prog_array_delete_safe(old_array, event->prog); | |
1748 | } else { | |
1749 | rcu_assign_pointer(event->tp_event->prog_array, new_array); | |
1750 | bpf_prog_array_free(old_array); | |
1751 | } | |
1752 | ||
1753 | bpf_prog_put(event->prog); | |
1754 | event->prog = NULL; | |
1755 | ||
07c41a29 | 1756 | unlock: |
e87c6bc3 YS |
1757 | mutex_unlock(&bpf_event_mutex); |
1758 | } | |
f371b304 | 1759 | |
f4e2298e | 1760 | int perf_event_query_prog_array(struct perf_event *event, void __user *info) |
f371b304 YS |
1761 | { |
1762 | struct perf_event_query_bpf __user *uquery = info; | |
1763 | struct perf_event_query_bpf query = {}; | |
e672db03 | 1764 | struct bpf_prog_array *progs; |
3a38bb98 | 1765 | u32 *ids, prog_cnt, ids_len; |
f371b304 YS |
1766 | int ret; |
1767 | ||
031258da | 1768 | if (!perfmon_capable()) |
f371b304 YS |
1769 | return -EPERM; |
1770 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
1771 | return -EINVAL; | |
1772 | if (copy_from_user(&query, uquery, sizeof(query))) | |
1773 | return -EFAULT; | |
3a38bb98 YS |
1774 | |
1775 | ids_len = query.ids_len; | |
1776 | if (ids_len > BPF_TRACE_MAX_PROGS) | |
9c481b90 | 1777 | return -E2BIG; |
3a38bb98 YS |
1778 | ids = kcalloc(ids_len, sizeof(u32), GFP_USER | __GFP_NOWARN); |
1779 | if (!ids) | |
1780 | return -ENOMEM; | |
1781 | /* | |
1782 | * The above kcalloc returns ZERO_SIZE_PTR when ids_len = 0, which | |
1783 | * is required when user only wants to check for uquery->prog_cnt. | |
1784 | * There is no need to check for it since the case is handled | |
1785 | * gracefully in bpf_prog_array_copy_info. | |
1786 | */ | |
f371b304 YS |
1787 | |
1788 | mutex_lock(&bpf_event_mutex); | |
e672db03 SF |
1789 | progs = bpf_event_rcu_dereference(event->tp_event->prog_array); |
1790 | ret = bpf_prog_array_copy_info(progs, ids, ids_len, &prog_cnt); | |
f371b304 YS |
1791 | mutex_unlock(&bpf_event_mutex); |
1792 | ||
3a38bb98 YS |
1793 | if (copy_to_user(&uquery->prog_cnt, &prog_cnt, sizeof(prog_cnt)) || |
1794 | copy_to_user(uquery->ids, ids, ids_len * sizeof(u32))) | |
1795 | ret = -EFAULT; | |
1796 | ||
1797 | kfree(ids); | |
f371b304 YS |
1798 | return ret; |
1799 | } | |
c4f6699d AS |
1800 | |
1801 | extern struct bpf_raw_event_map __start__bpf_raw_tp[]; | |
1802 | extern struct bpf_raw_event_map __stop__bpf_raw_tp[]; | |
1803 | ||
a38d1107 | 1804 | struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name) |
c4f6699d AS |
1805 | { |
1806 | struct bpf_raw_event_map *btp = __start__bpf_raw_tp; | |
1807 | ||
1808 | for (; btp < __stop__bpf_raw_tp; btp++) { | |
1809 | if (!strcmp(btp->tp->name, name)) | |
1810 | return btp; | |
1811 | } | |
a38d1107 MM |
1812 | |
1813 | return bpf_get_raw_tracepoint_module(name); | |
1814 | } | |
1815 | ||
1816 | void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp) | |
1817 | { | |
1818 | struct module *mod = __module_address((unsigned long)btp); | |
1819 | ||
1820 | if (mod) | |
1821 | module_put(mod); | |
c4f6699d AS |
1822 | } |
1823 | ||
1824 | static __always_inline | |
1825 | void __bpf_trace_run(struct bpf_prog *prog, u64 *args) | |
1826 | { | |
f03efe49 | 1827 | cant_sleep(); |
c4f6699d | 1828 | rcu_read_lock(); |
c4f6699d | 1829 | (void) BPF_PROG_RUN(prog, args); |
c4f6699d AS |
1830 | rcu_read_unlock(); |
1831 | } | |
1832 | ||
1833 | #define UNPACK(...) __VA_ARGS__ | |
1834 | #define REPEAT_1(FN, DL, X, ...) FN(X) | |
1835 | #define REPEAT_2(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__) | |
1836 | #define REPEAT_3(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__) | |
1837 | #define REPEAT_4(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__) | |
1838 | #define REPEAT_5(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__) | |
1839 | #define REPEAT_6(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__) | |
1840 | #define REPEAT_7(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__) | |
1841 | #define REPEAT_8(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__) | |
1842 | #define REPEAT_9(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__) | |
1843 | #define REPEAT_10(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__) | |
1844 | #define REPEAT_11(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__) | |
1845 | #define REPEAT_12(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__) | |
1846 | #define REPEAT(X, FN, DL, ...) REPEAT_##X(FN, DL, __VA_ARGS__) | |
1847 | ||
1848 | #define SARG(X) u64 arg##X | |
1849 | #define COPY(X) args[X] = arg##X | |
1850 | ||
1851 | #define __DL_COM (,) | |
1852 | #define __DL_SEM (;) | |
1853 | ||
1854 | #define __SEQ_0_11 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 | |
1855 | ||
1856 | #define BPF_TRACE_DEFN_x(x) \ | |
1857 | void bpf_trace_run##x(struct bpf_prog *prog, \ | |
1858 | REPEAT(x, SARG, __DL_COM, __SEQ_0_11)) \ | |
1859 | { \ | |
1860 | u64 args[x]; \ | |
1861 | REPEAT(x, COPY, __DL_SEM, __SEQ_0_11); \ | |
1862 | __bpf_trace_run(prog, args); \ | |
1863 | } \ | |
1864 | EXPORT_SYMBOL_GPL(bpf_trace_run##x) | |
1865 | BPF_TRACE_DEFN_x(1); | |
1866 | BPF_TRACE_DEFN_x(2); | |
1867 | BPF_TRACE_DEFN_x(3); | |
1868 | BPF_TRACE_DEFN_x(4); | |
1869 | BPF_TRACE_DEFN_x(5); | |
1870 | BPF_TRACE_DEFN_x(6); | |
1871 | BPF_TRACE_DEFN_x(7); | |
1872 | BPF_TRACE_DEFN_x(8); | |
1873 | BPF_TRACE_DEFN_x(9); | |
1874 | BPF_TRACE_DEFN_x(10); | |
1875 | BPF_TRACE_DEFN_x(11); | |
1876 | BPF_TRACE_DEFN_x(12); | |
1877 | ||
1878 | static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog) | |
1879 | { | |
1880 | struct tracepoint *tp = btp->tp; | |
1881 | ||
1882 | /* | |
1883 | * check that program doesn't access arguments beyond what's | |
1884 | * available in this tracepoint | |
1885 | */ | |
1886 | if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64)) | |
1887 | return -EINVAL; | |
1888 | ||
9df1c28b MM |
1889 | if (prog->aux->max_tp_access > btp->writable_size) |
1890 | return -EINVAL; | |
1891 | ||
c4f6699d AS |
1892 | return tracepoint_probe_register(tp, (void *)btp->bpf_func, prog); |
1893 | } | |
1894 | ||
1895 | int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog) | |
1896 | { | |
e16ec340 | 1897 | return __bpf_probe_register(btp, prog); |
c4f6699d AS |
1898 | } |
1899 | ||
1900 | int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog) | |
1901 | { | |
e16ec340 | 1902 | return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog); |
c4f6699d | 1903 | } |
41bdc4b4 YS |
1904 | |
1905 | int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, | |
1906 | u32 *fd_type, const char **buf, | |
1907 | u64 *probe_offset, u64 *probe_addr) | |
1908 | { | |
1909 | bool is_tracepoint, is_syscall_tp; | |
1910 | struct bpf_prog *prog; | |
1911 | int flags, err = 0; | |
1912 | ||
1913 | prog = event->prog; | |
1914 | if (!prog) | |
1915 | return -ENOENT; | |
1916 | ||
1917 | /* not supporting BPF_PROG_TYPE_PERF_EVENT yet */ | |
1918 | if (prog->type == BPF_PROG_TYPE_PERF_EVENT) | |
1919 | return -EOPNOTSUPP; | |
1920 | ||
1921 | *prog_id = prog->aux->id; | |
1922 | flags = event->tp_event->flags; | |
1923 | is_tracepoint = flags & TRACE_EVENT_FL_TRACEPOINT; | |
1924 | is_syscall_tp = is_syscall_trace_event(event->tp_event); | |
1925 | ||
1926 | if (is_tracepoint || is_syscall_tp) { | |
1927 | *buf = is_tracepoint ? event->tp_event->tp->name | |
1928 | : event->tp_event->name; | |
1929 | *fd_type = BPF_FD_TYPE_TRACEPOINT; | |
1930 | *probe_offset = 0x0; | |
1931 | *probe_addr = 0x0; | |
1932 | } else { | |
1933 | /* kprobe/uprobe */ | |
1934 | err = -EOPNOTSUPP; | |
1935 | #ifdef CONFIG_KPROBE_EVENTS | |
1936 | if (flags & TRACE_EVENT_FL_KPROBE) | |
1937 | err = bpf_get_kprobe_info(event, fd_type, buf, | |
1938 | probe_offset, probe_addr, | |
1939 | event->attr.type == PERF_TYPE_TRACEPOINT); | |
1940 | #endif | |
1941 | #ifdef CONFIG_UPROBE_EVENTS | |
1942 | if (flags & TRACE_EVENT_FL_UPROBE) | |
1943 | err = bpf_get_uprobe_info(event, fd_type, buf, | |
1944 | probe_offset, | |
1945 | event->attr.type == PERF_TYPE_TRACEPOINT); | |
1946 | #endif | |
1947 | } | |
1948 | ||
1949 | return err; | |
1950 | } | |
a38d1107 | 1951 | |
9db1ff0a YS |
1952 | static int __init send_signal_irq_work_init(void) |
1953 | { | |
1954 | int cpu; | |
1955 | struct send_signal_irq_work *work; | |
1956 | ||
1957 | for_each_possible_cpu(cpu) { | |
1958 | work = per_cpu_ptr(&send_signal_work, cpu); | |
1959 | init_irq_work(&work->irq_work, do_bpf_send_signal); | |
1960 | } | |
1961 | return 0; | |
1962 | } | |
1963 | ||
1964 | subsys_initcall(send_signal_irq_work_init); | |
1965 | ||
a38d1107 | 1966 | #ifdef CONFIG_MODULES |
390e99cf SF |
1967 | static int bpf_event_notify(struct notifier_block *nb, unsigned long op, |
1968 | void *module) | |
a38d1107 MM |
1969 | { |
1970 | struct bpf_trace_module *btm, *tmp; | |
1971 | struct module *mod = module; | |
1972 | ||
1973 | if (mod->num_bpf_raw_events == 0 || | |
1974 | (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING)) | |
1975 | return 0; | |
1976 | ||
1977 | mutex_lock(&bpf_module_mutex); | |
1978 | ||
1979 | switch (op) { | |
1980 | case MODULE_STATE_COMING: | |
1981 | btm = kzalloc(sizeof(*btm), GFP_KERNEL); | |
1982 | if (btm) { | |
1983 | btm->module = module; | |
1984 | list_add(&btm->list, &bpf_trace_modules); | |
1985 | } | |
1986 | break; | |
1987 | case MODULE_STATE_GOING: | |
1988 | list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) { | |
1989 | if (btm->module == module) { | |
1990 | list_del(&btm->list); | |
1991 | kfree(btm); | |
1992 | break; | |
1993 | } | |
1994 | } | |
1995 | break; | |
1996 | } | |
1997 | ||
1998 | mutex_unlock(&bpf_module_mutex); | |
1999 | ||
2000 | return 0; | |
2001 | } | |
2002 | ||
2003 | static struct notifier_block bpf_module_nb = { | |
2004 | .notifier_call = bpf_event_notify, | |
2005 | }; | |
2006 | ||
390e99cf | 2007 | static int __init bpf_event_init(void) |
a38d1107 MM |
2008 | { |
2009 | register_module_notifier(&bpf_module_nb); | |
2010 | return 0; | |
2011 | } | |
2012 | ||
2013 | fs_initcall(bpf_event_init); | |
2014 | #endif /* CONFIG_MODULES */ |