Commit | Line | Data |
---|---|---|
bcea3f96 | 1 | // SPDX-License-Identifier: GPL-2.0 |
413d37d1 | 2 | /* |
77b44d1b | 3 | * Kprobes-based tracing events |
413d37d1 MH |
4 | * |
5 | * Created by Masami Hiramatsu <mhiramat@redhat.com> | |
6 | * | |
413d37d1 | 7 | */ |
72576341 | 8 | #define pr_fmt(fmt) "trace_kprobe: " fmt |
413d37d1 | 9 | |
17911ff3 | 10 | #include <linux/security.h> |
413d37d1 MH |
11 | #include <linux/module.h> |
12 | #include <linux/uaccess.h> | |
b2d09103 | 13 | #include <linux/rculist.h> |
540adea3 | 14 | #include <linux/error-injection.h> |
413d37d1 | 15 | |
970988e1 MH |
16 | #include <asm/setup.h> /* for COMMAND_LINE_SIZE */ |
17 | ||
6212dd29 | 18 | #include "trace_dynevent.h" |
d899926f | 19 | #include "trace_kprobe_selftest.h" |
8ab83f56 | 20 | #include "trace_probe.h" |
53305928 | 21 | #include "trace_probe_tmpl.h" |
1ff511e3 | 22 | |
8ab83f56 | 23 | #define KPROBE_EVENT_SYSTEM "kprobes" |
696ced4f | 24 | #define KRETPROBE_MAXACTIVE_MAX 4096 |
970988e1 MH |
25 | |
26 | /* Kprobe early definition from command line */ | |
27 | static char kprobe_boot_events_buf[COMMAND_LINE_SIZE] __initdata; | |
28 | ||
29 | static int __init set_kprobe_boot_events(char *str) | |
30 | { | |
31 | strlcpy(kprobe_boot_events_buf, str, COMMAND_LINE_SIZE); | |
60efe21e MH |
32 | disable_tracing_selftest("running kprobe events"); |
33 | ||
970988e1 MH |
34 | return 0; |
35 | } | |
36 | __setup("kprobe_event=", set_kprobe_boot_events); | |
e09c8614 | 37 | |
d262271d | 38 | static int trace_kprobe_create(const char *raw_command); |
6212dd29 MH |
39 | static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev); |
40 | static int trace_kprobe_release(struct dyn_event *ev); | |
41 | static bool trace_kprobe_is_busy(struct dyn_event *ev); | |
42 | static bool trace_kprobe_match(const char *system, const char *event, | |
30199137 | 43 | int argc, const char **argv, struct dyn_event *ev); |
6212dd29 MH |
44 | |
45 | static struct dyn_event_operations trace_kprobe_ops = { | |
46 | .create = trace_kprobe_create, | |
47 | .show = trace_kprobe_show, | |
48 | .is_busy = trace_kprobe_is_busy, | |
49 | .free = trace_kprobe_release, | |
50 | .match = trace_kprobe_match, | |
51 | }; | |
52 | ||
cede666e | 53 | /* |
77b44d1b | 54 | * Kprobe event core functions |
413d37d1 | 55 | */ |
c31ffb3f | 56 | struct trace_kprobe { |
6212dd29 | 57 | struct dyn_event devent; |
4a846b44 | 58 | struct kretprobe rp; /* Use rp.kp for kprobe use */ |
a7636d9e | 59 | unsigned long __percpu *nhit; |
413d37d1 | 60 | const char *symbol; /* symbol name */ |
c31ffb3f | 61 | struct trace_probe tp; |
413d37d1 MH |
62 | }; |
63 | ||
6212dd29 MH |
64 | static bool is_trace_kprobe(struct dyn_event *ev) |
65 | { | |
66 | return ev->ops == &trace_kprobe_ops; | |
67 | } | |
68 | ||
69 | static struct trace_kprobe *to_trace_kprobe(struct dyn_event *ev) | |
70 | { | |
71 | return container_of(ev, struct trace_kprobe, devent); | |
72 | } | |
73 | ||
74 | /** | |
75 | * for_each_trace_kprobe - iterate over the trace_kprobe list | |
76 | * @pos: the struct trace_kprobe * for each entry | |
77 | * @dpos: the struct dyn_event * to use as a loop cursor | |
78 | */ | |
79 | #define for_each_trace_kprobe(pos, dpos) \ | |
80 | for_each_dyn_event(dpos) \ | |
81 | if (is_trace_kprobe(dpos) && (pos = to_trace_kprobe(dpos))) | |
82 | ||
c31ffb3f NK |
83 | #define SIZEOF_TRACE_KPROBE(n) \ |
84 | (offsetof(struct trace_kprobe, tp.args) + \ | |
eca0d916 | 85 | (sizeof(struct probe_arg) * (n))) |
a82378d8 | 86 | |
3da0f180 | 87 | static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk) |
413d37d1 | 88 | { |
c31ffb3f | 89 | return tk->rp.handler != NULL; |
413d37d1 MH |
90 | } |
91 | ||
3da0f180 | 92 | static nokprobe_inline const char *trace_kprobe_symbol(struct trace_kprobe *tk) |
413d37d1 | 93 | { |
c31ffb3f | 94 | return tk->symbol ? tk->symbol : "unknown"; |
413d37d1 MH |
95 | } |
96 | ||
3da0f180 | 97 | static nokprobe_inline unsigned long trace_kprobe_offset(struct trace_kprobe *tk) |
61424318 | 98 | { |
c31ffb3f | 99 | return tk->rp.kp.offset; |
61424318 MH |
100 | } |
101 | ||
3da0f180 | 102 | static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk) |
61424318 | 103 | { |
c31ffb3f | 104 | return !!(kprobe_gone(&tk->rp.kp)); |
61424318 MH |
105 | } |
106 | ||
3da0f180 | 107 | static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, |
c31ffb3f | 108 | struct module *mod) |
61424318 | 109 | { |
f3d36426 | 110 | int len = strlen(module_name(mod)); |
c31ffb3f | 111 | const char *name = trace_kprobe_symbol(tk); |
f3d36426 JS |
112 | |
113 | return strncmp(module_name(mod), name, len) == 0 && name[len] == ':'; | |
61424318 MH |
114 | } |
115 | ||
59158ec4 | 116 | static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) |
61424318 | 117 | { |
59158ec4 MH |
118 | char *p; |
119 | bool ret; | |
120 | ||
121 | if (!tk->symbol) | |
122 | return false; | |
123 | p = strchr(tk->symbol, ':'); | |
124 | if (!p) | |
125 | return true; | |
126 | *p = '\0'; | |
a0060505 | 127 | rcu_read_lock_sched(); |
59158ec4 | 128 | ret = !!find_module(tk->symbol); |
a0060505 | 129 | rcu_read_unlock_sched(); |
59158ec4 MH |
130 | *p = ':'; |
131 | ||
132 | return ret; | |
61424318 MH |
133 | } |
134 | ||
6212dd29 MH |
135 | static bool trace_kprobe_is_busy(struct dyn_event *ev) |
136 | { | |
137 | struct trace_kprobe *tk = to_trace_kprobe(ev); | |
138 | ||
139 | return trace_probe_is_enabled(&tk->tp); | |
140 | } | |
141 | ||
eb5bf813 MH |
142 | static bool trace_kprobe_match_command_head(struct trace_kprobe *tk, |
143 | int argc, const char **argv) | |
144 | { | |
145 | char buf[MAX_ARGSTR_LEN + 1]; | |
146 | ||
147 | if (!argc) | |
148 | return true; | |
149 | ||
150 | if (!tk->symbol) | |
151 | snprintf(buf, sizeof(buf), "0x%p", tk->rp.kp.addr); | |
152 | else if (tk->rp.kp.offset) | |
153 | snprintf(buf, sizeof(buf), "%s+%u", | |
154 | trace_kprobe_symbol(tk), tk->rp.kp.offset); | |
155 | else | |
156 | snprintf(buf, sizeof(buf), "%s", trace_kprobe_symbol(tk)); | |
157 | if (strcmp(buf, argv[0])) | |
158 | return false; | |
159 | argc--; argv++; | |
160 | ||
161 | return trace_probe_match_command_args(&tk->tp, argc, argv); | |
162 | } | |
163 | ||
6212dd29 | 164 | static bool trace_kprobe_match(const char *system, const char *event, |
30199137 | 165 | int argc, const char **argv, struct dyn_event *ev) |
6212dd29 MH |
166 | { |
167 | struct trace_kprobe *tk = to_trace_kprobe(ev); | |
168 | ||
b55ce203 | 169 | return strcmp(trace_probe_name(&tk->tp), event) == 0 && |
eb5bf813 MH |
170 | (!system || strcmp(trace_probe_group_name(&tk->tp), system) == 0) && |
171 | trace_kprobe_match_command_head(tk, argc, argv); | |
6212dd29 MH |
172 | } |
173 | ||
f18f97ac MN |
174 | static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk) |
175 | { | |
176 | unsigned long nhit = 0; | |
177 | int cpu; | |
178 | ||
179 | for_each_possible_cpu(cpu) | |
180 | nhit += *per_cpu_ptr(tk->nhit, cpu); | |
181 | ||
182 | return nhit; | |
183 | } | |
184 | ||
715fa2fd MH |
185 | static nokprobe_inline bool trace_kprobe_is_registered(struct trace_kprobe *tk) |
186 | { | |
187 | return !(list_empty(&tk->rp.kp.list) && | |
188 | hlist_unhashed(&tk->rp.kp.hlist)); | |
189 | } | |
190 | ||
6bc6c77c | 191 | /* Return 0 if it fails to find the symbol address */ |
45408c4f MH |
192 | static nokprobe_inline |
193 | unsigned long trace_kprobe_address(struct trace_kprobe *tk) | |
194 | { | |
195 | unsigned long addr; | |
196 | ||
197 | if (tk->symbol) { | |
198 | addr = (unsigned long) | |
199 | kallsyms_lookup_name(trace_kprobe_symbol(tk)); | |
6bc6c77c MH |
200 | if (addr) |
201 | addr += tk->rp.kp.offset; | |
45408c4f MH |
202 | } else { |
203 | addr = (unsigned long)tk->rp.kp.addr; | |
204 | } | |
205 | return addr; | |
206 | } | |
207 | ||
60d53e2c MH |
208 | static nokprobe_inline struct trace_kprobe * |
209 | trace_kprobe_primary_from_call(struct trace_event_call *call) | |
210 | { | |
211 | struct trace_probe *tp; | |
212 | ||
213 | tp = trace_probe_primary_from_call(call); | |
214 | if (WARN_ON_ONCE(!tp)) | |
215 | return NULL; | |
216 | ||
217 | return container_of(tp, struct trace_kprobe, tp); | |
218 | } | |
219 | ||
b4da3340 | 220 | bool trace_kprobe_on_func_entry(struct trace_event_call *call) |
9802d865 | 221 | { |
60d53e2c | 222 | struct trace_kprobe *tk = trace_kprobe_primary_from_call(call); |
b4da3340 | 223 | |
97c753e6 | 224 | return tk ? (kprobe_on_func_entry(tk->rp.kp.addr, |
b4da3340 | 225 | tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name, |
97c753e6 | 226 | tk->rp.kp.addr ? 0 : tk->rp.kp.offset) == 0) : false; |
9802d865 JB |
227 | } |
228 | ||
b4da3340 | 229 | bool trace_kprobe_error_injectable(struct trace_event_call *call) |
9802d865 | 230 | { |
60d53e2c | 231 | struct trace_kprobe *tk = trace_kprobe_primary_from_call(call); |
9802d865 | 232 | |
60d53e2c MH |
233 | return tk ? within_error_injection_list(trace_kprobe_address(tk)) : |
234 | false; | |
9802d865 JB |
235 | } |
236 | ||
c31ffb3f NK |
237 | static int register_kprobe_event(struct trace_kprobe *tk); |
238 | static int unregister_kprobe_event(struct trace_kprobe *tk); | |
413d37d1 | 239 | |
50d78056 MH |
240 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); |
241 | static int kretprobe_dispatcher(struct kretprobe_instance *ri, | |
242 | struct pt_regs *regs); | |
243 | ||
455b2899 MH |
244 | static void free_trace_kprobe(struct trace_kprobe *tk) |
245 | { | |
246 | if (tk) { | |
247 | trace_probe_cleanup(&tk->tp); | |
248 | kfree(tk->symbol); | |
249 | free_percpu(tk->nhit); | |
250 | kfree(tk); | |
251 | } | |
252 | } | |
253 | ||
4a846b44 MH |
254 | /* |
255 | * Allocate new trace_probe and initialize it (including kprobes). | |
256 | */ | |
c31ffb3f | 257 | static struct trace_kprobe *alloc_trace_kprobe(const char *group, |
f52487e9 | 258 | const char *event, |
4a846b44 MH |
259 | void *addr, |
260 | const char *symbol, | |
261 | unsigned long offs, | |
696ced4f | 262 | int maxactive, |
3a6b7666 | 263 | int nargs, bool is_return) |
413d37d1 | 264 | { |
c31ffb3f | 265 | struct trace_kprobe *tk; |
6f3cf440 | 266 | int ret = -ENOMEM; |
413d37d1 | 267 | |
c31ffb3f NK |
268 | tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL); |
269 | if (!tk) | |
6f3cf440 | 270 | return ERR_PTR(ret); |
413d37d1 | 271 | |
a7636d9e MKL |
272 | tk->nhit = alloc_percpu(unsigned long); |
273 | if (!tk->nhit) | |
274 | goto error; | |
275 | ||
413d37d1 | 276 | if (symbol) { |
c31ffb3f NK |
277 | tk->symbol = kstrdup(symbol, GFP_KERNEL); |
278 | if (!tk->symbol) | |
413d37d1 | 279 | goto error; |
c31ffb3f NK |
280 | tk->rp.kp.symbol_name = tk->symbol; |
281 | tk->rp.kp.offset = offs; | |
4a846b44 | 282 | } else |
c31ffb3f | 283 | tk->rp.kp.addr = addr; |
4a846b44 MH |
284 | |
285 | if (is_return) | |
c31ffb3f | 286 | tk->rp.handler = kretprobe_dispatcher; |
4a846b44 | 287 | else |
c31ffb3f | 288 | tk->rp.kp.pre_handler = kprobe_dispatcher; |
4a846b44 | 289 | |
696ced4f | 290 | tk->rp.maxactive = maxactive; |
715fa2fd MH |
291 | INIT_HLIST_NODE(&tk->rp.kp.hlist); |
292 | INIT_LIST_HEAD(&tk->rp.kp.list); | |
696ced4f | 293 | |
b61387cb | 294 | ret = trace_probe_init(&tk->tp, event, group, false); |
455b2899 | 295 | if (ret < 0) |
f52487e9 MH |
296 | goto error; |
297 | ||
6212dd29 | 298 | dyn_event_init(&tk->devent, &trace_kprobe_ops); |
c31ffb3f | 299 | return tk; |
413d37d1 | 300 | error: |
455b2899 | 301 | free_trace_kprobe(tk); |
6f3cf440 | 302 | return ERR_PTR(ret); |
413d37d1 MH |
303 | } |
304 | ||
c31ffb3f NK |
305 | static struct trace_kprobe *find_trace_kprobe(const char *event, |
306 | const char *group) | |
413d37d1 | 307 | { |
6212dd29 | 308 | struct dyn_event *pos; |
c31ffb3f | 309 | struct trace_kprobe *tk; |
413d37d1 | 310 | |
6212dd29 | 311 | for_each_trace_kprobe(tk, pos) |
b55ce203 MH |
312 | if (strcmp(trace_probe_name(&tk->tp), event) == 0 && |
313 | strcmp(trace_probe_group_name(&tk->tp), group) == 0) | |
c31ffb3f | 314 | return tk; |
413d37d1 MH |
315 | return NULL; |
316 | } | |
317 | ||
87107a25 SRV |
318 | static inline int __enable_trace_kprobe(struct trace_kprobe *tk) |
319 | { | |
320 | int ret = 0; | |
321 | ||
715fa2fd | 322 | if (trace_kprobe_is_registered(tk) && !trace_kprobe_has_gone(tk)) { |
87107a25 SRV |
323 | if (trace_kprobe_is_return(tk)) |
324 | ret = enable_kretprobe(&tk->rp); | |
325 | else | |
326 | ret = enable_kprobe(&tk->rp.kp); | |
327 | } | |
328 | ||
329 | return ret; | |
330 | } | |
331 | ||
60d53e2c MH |
332 | static void __disable_trace_kprobe(struct trace_probe *tp) |
333 | { | |
334 | struct trace_probe *pos; | |
335 | struct trace_kprobe *tk; | |
336 | ||
337 | list_for_each_entry(pos, trace_probe_probe_list(tp), list) { | |
338 | tk = container_of(pos, struct trace_kprobe, tp); | |
339 | if (!trace_kprobe_is_registered(tk)) | |
340 | continue; | |
341 | if (trace_kprobe_is_return(tk)) | |
342 | disable_kretprobe(&tk->rp); | |
343 | else | |
344 | disable_kprobe(&tk->rp.kp); | |
345 | } | |
346 | } | |
347 | ||
41a7dd42 MH |
348 | /* |
349 | * Enable trace_probe | |
350 | * if the file is NULL, enable "perf" handler, or enable "trace" handler. | |
351 | */ | |
60d53e2c MH |
352 | static int enable_trace_kprobe(struct trace_event_call *call, |
353 | struct trace_event_file *file) | |
1538f888 | 354 | { |
60d53e2c MH |
355 | struct trace_probe *pos, *tp; |
356 | struct trace_kprobe *tk; | |
357 | bool enabled; | |
1538f888 MH |
358 | int ret = 0; |
359 | ||
60d53e2c MH |
360 | tp = trace_probe_primary_from_call(call); |
361 | if (WARN_ON_ONCE(!tp)) | |
362 | return -ENODEV; | |
363 | enabled = trace_probe_is_enabled(tp); | |
364 | ||
365 | /* This also changes "enabled" state */ | |
41a7dd42 | 366 | if (file) { |
60d53e2c | 367 | ret = trace_probe_add_file(tp, file); |
b5f935ee MH |
368 | if (ret) |
369 | return ret; | |
370 | } else | |
60d53e2c | 371 | trace_probe_set_flag(tp, TP_FLAG_PROFILE); |
41a7dd42 | 372 | |
b5f935ee MH |
373 | if (enabled) |
374 | return 0; | |
87107a25 | 375 | |
60d53e2c MH |
376 | list_for_each_entry(pos, trace_probe_probe_list(tp), list) { |
377 | tk = container_of(pos, struct trace_kprobe, tp); | |
378 | if (trace_kprobe_has_gone(tk)) | |
379 | continue; | |
380 | ret = __enable_trace_kprobe(tk); | |
44d00dc7 | 381 | if (ret) |
60d53e2c | 382 | break; |
60d53e2c MH |
383 | enabled = true; |
384 | } | |
385 | ||
44d00dc7 MH |
386 | if (ret) { |
387 | /* Failed to enable one of them. Roll back all */ | |
388 | if (enabled) | |
389 | __disable_trace_kprobe(tp); | |
b5f935ee | 390 | if (file) |
60d53e2c | 391 | trace_probe_remove_file(tp, file); |
b5f935ee | 392 | else |
60d53e2c | 393 | trace_probe_clear_flag(tp, TP_FLAG_PROFILE); |
57ea2a34 | 394 | } |
b5f935ee | 395 | |
1538f888 MH |
396 | return ret; |
397 | } | |
398 | ||
41a7dd42 MH |
399 | /* |
400 | * Disable trace_probe | |
401 | * if the file is NULL, disable "perf" handler, or disable "trace" handler. | |
402 | */ | |
60d53e2c MH |
403 | static int disable_trace_kprobe(struct trace_event_call *call, |
404 | struct trace_event_file *file) | |
1538f888 | 405 | { |
60d53e2c MH |
406 | struct trace_probe *tp; |
407 | ||
408 | tp = trace_probe_primary_from_call(call); | |
409 | if (WARN_ON_ONCE(!tp)) | |
410 | return -ENODEV; | |
41a7dd42 | 411 | |
41a7dd42 | 412 | if (file) { |
b5f935ee MH |
413 | if (!trace_probe_get_file_link(tp, file)) |
414 | return -ENOENT; | |
415 | if (!trace_probe_has_single_file(tp)) | |
b04d52e3 | 416 | goto out; |
747774d6 | 417 | trace_probe_clear_flag(tp, TP_FLAG_TRACE); |
41a7dd42 | 418 | } else |
747774d6 | 419 | trace_probe_clear_flag(tp, TP_FLAG_PROFILE); |
41a7dd42 | 420 | |
60d53e2c MH |
421 | if (!trace_probe_is_enabled(tp)) |
422 | __disable_trace_kprobe(tp); | |
e12f03d7 | 423 | |
3fe3d619 | 424 | out: |
b5f935ee | 425 | if (file) |
a232e270 | 426 | /* |
b5f935ee MH |
427 | * Synchronization is done in below function. For perf event, |
428 | * file == NULL and perf_trace_event_unreg() calls | |
429 | * tracepoint_synchronize_unregister() to ensure synchronize | |
430 | * event. We don't need to care about it. | |
a232e270 | 431 | */ |
b5f935ee | 432 | trace_probe_remove_file(tp, file); |
a232e270 | 433 | |
60d53e2c | 434 | return 0; |
1538f888 MH |
435 | } |
436 | ||
7bb83f6f | 437 | #if defined(CONFIG_DYNAMIC_FTRACE) && \ |
45408c4f | 438 | !defined(CONFIG_KPROBE_EVENTS_ON_NOTRACE) |
c7411a1a | 439 | static bool __within_notrace_func(unsigned long addr) |
45408c4f | 440 | { |
c7411a1a | 441 | unsigned long offset, size; |
45408c4f | 442 | |
6bc6c77c MH |
443 | if (!addr || !kallsyms_lookup_size_offset(addr, &size, &offset)) |
444 | return false; | |
45408c4f | 445 | |
9161a864 MH |
446 | /* Get the entry address of the target function */ |
447 | addr -= offset; | |
448 | ||
449 | /* | |
450 | * Since ftrace_location_range() does inclusive range check, we need | |
451 | * to subtract 1 byte from the end address. | |
452 | */ | |
453 | return !ftrace_location_range(addr, addr + size - 1); | |
45408c4f | 454 | } |
c7411a1a MH |
455 | |
456 | static bool within_notrace_func(struct trace_kprobe *tk) | |
457 | { | |
dcbd21c9 | 458 | unsigned long addr = trace_kprobe_address(tk); |
c7411a1a MH |
459 | char symname[KSYM_NAME_LEN], *p; |
460 | ||
461 | if (!__within_notrace_func(addr)) | |
462 | return false; | |
463 | ||
464 | /* Check if the address is on a suffixed-symbol */ | |
465 | if (!lookup_symbol_name(addr, symname)) { | |
466 | p = strchr(symname, '.'); | |
467 | if (!p) | |
468 | return true; | |
469 | *p = '\0'; | |
470 | addr = (unsigned long)kprobe_lookup_name(symname, 0); | |
471 | if (addr) | |
472 | return __within_notrace_func(addr); | |
473 | } | |
474 | ||
475 | return true; | |
476 | } | |
45408c4f MH |
477 | #else |
478 | #define within_notrace_func(tk) (false) | |
479 | #endif | |
480 | ||
61424318 | 481 | /* Internal register function - just handle k*probes and flags */ |
c31ffb3f | 482 | static int __register_trace_kprobe(struct trace_kprobe *tk) |
413d37d1 | 483 | { |
a6682814 | 484 | int i, ret; |
61424318 | 485 | |
a94549dd DH |
486 | ret = security_locked_down(LOCKDOWN_KPROBES); |
487 | if (ret) | |
488 | return ret; | |
489 | ||
715fa2fd | 490 | if (trace_kprobe_is_registered(tk)) |
61424318 MH |
491 | return -EINVAL; |
492 | ||
45408c4f MH |
493 | if (within_notrace_func(tk)) { |
494 | pr_warn("Could not probe notrace function %s\n", | |
495 | trace_kprobe_symbol(tk)); | |
496 | return -EINVAL; | |
497 | } | |
498 | ||
a6682814 MH |
499 | for (i = 0; i < tk->tp.nr_args; i++) { |
500 | ret = traceprobe_update_arg(&tk->tp.args[i]); | |
501 | if (ret) | |
502 | return ret; | |
503 | } | |
504 | ||
61424318 | 505 | /* Set/clear disabled flag according to tp->flag */ |
c31ffb3f NK |
506 | if (trace_probe_is_enabled(&tk->tp)) |
507 | tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; | |
61424318 | 508 | else |
c31ffb3f | 509 | tk->rp.kp.flags |= KPROBE_FLAG_DISABLED; |
61424318 | 510 | |
c31ffb3f NK |
511 | if (trace_kprobe_is_return(tk)) |
512 | ret = register_kretprobe(&tk->rp); | |
413d37d1 | 513 | else |
c31ffb3f | 514 | ret = register_kprobe(&tk->rp.kp); |
61424318 | 515 | |
61424318 MH |
516 | return ret; |
517 | } | |
518 | ||
519 | /* Internal unregister function - just handle k*probes and flags */ | |
c31ffb3f | 520 | static void __unregister_trace_kprobe(struct trace_kprobe *tk) |
61424318 | 521 | { |
715fa2fd | 522 | if (trace_kprobe_is_registered(tk)) { |
c31ffb3f NK |
523 | if (trace_kprobe_is_return(tk)) |
524 | unregister_kretprobe(&tk->rp); | |
61424318 | 525 | else |
c31ffb3f | 526 | unregister_kprobe(&tk->rp.kp); |
715fa2fd MH |
527 | /* Cleanup kprobe for reuse and mark it unregistered */ |
528 | INIT_HLIST_NODE(&tk->rp.kp.hlist); | |
529 | INIT_LIST_HEAD(&tk->rp.kp.list); | |
c31ffb3f NK |
530 | if (tk->rp.kp.symbol_name) |
531 | tk->rp.kp.addr = NULL; | |
61424318 MH |
532 | } |
533 | } | |
534 | ||
6212dd29 | 535 | /* Unregister a trace_probe and probe_event */ |
c31ffb3f | 536 | static int unregister_trace_kprobe(struct trace_kprobe *tk) |
61424318 | 537 | { |
ca89bc07 MH |
538 | /* If other probes are on the event, just unregister kprobe */ |
539 | if (trace_probe_has_sibling(&tk->tp)) | |
540 | goto unreg; | |
541 | ||
02ca1521 | 542 | /* Enabled event can not be unregistered */ |
c31ffb3f | 543 | if (trace_probe_is_enabled(&tk->tp)) |
02ca1521 MH |
544 | return -EBUSY; |
545 | ||
40c32592 | 546 | /* Will fail if probe is being used by ftrace or perf */ |
c31ffb3f | 547 | if (unregister_kprobe_event(tk)) |
40c32592 SRRH |
548 | return -EBUSY; |
549 | ||
ca89bc07 | 550 | unreg: |
c31ffb3f | 551 | __unregister_trace_kprobe(tk); |
6212dd29 | 552 | dyn_event_remove(&tk->devent); |
ca89bc07 | 553 | trace_probe_unlink(&tk->tp); |
02ca1521 MH |
554 | |
555 | return 0; | |
413d37d1 MH |
556 | } |
557 | ||
fe60b0ce MH |
558 | static bool trace_kprobe_has_same_kprobe(struct trace_kprobe *orig, |
559 | struct trace_kprobe *comp) | |
560 | { | |
561 | struct trace_probe_event *tpe = orig->tp.event; | |
562 | struct trace_probe *pos; | |
563 | int i; | |
564 | ||
565 | list_for_each_entry(pos, &tpe->probes, list) { | |
566 | orig = container_of(pos, struct trace_kprobe, tp); | |
567 | if (strcmp(trace_kprobe_symbol(orig), | |
568 | trace_kprobe_symbol(comp)) || | |
569 | trace_kprobe_offset(orig) != trace_kprobe_offset(comp)) | |
570 | continue; | |
571 | ||
572 | /* | |
573 | * trace_probe_compare_arg_type() ensured that nr_args and | |
574 | * each argument name and type are same. Let's compare comm. | |
575 | */ | |
576 | for (i = 0; i < orig->tp.nr_args; i++) { | |
577 | if (strcmp(orig->tp.args[i].comm, | |
578 | comp->tp.args[i].comm)) | |
f8d7ab2b | 579 | break; |
fe60b0ce MH |
580 | } |
581 | ||
f8d7ab2b SD |
582 | if (i == orig->tp.nr_args) |
583 | return true; | |
fe60b0ce MH |
584 | } |
585 | ||
586 | return false; | |
587 | } | |
588 | ||
ca89bc07 MH |
589 | static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to) |
590 | { | |
591 | int ret; | |
592 | ||
fe60b0ce MH |
593 | ret = trace_probe_compare_arg_type(&tk->tp, &to->tp); |
594 | if (ret) { | |
595 | /* Note that argument starts index = 2 */ | |
596 | trace_probe_log_set_index(ret + 1); | |
597 | trace_probe_log_err(0, DIFF_ARG_TYPE); | |
598 | return -EEXIST; | |
599 | } | |
600 | if (trace_kprobe_has_same_kprobe(to, tk)) { | |
601 | trace_probe_log_set_index(0); | |
602 | trace_probe_log_err(0, SAME_PROBE); | |
603 | return -EEXIST; | |
604 | } | |
605 | ||
ca89bc07 MH |
606 | /* Append to existing event */ |
607 | ret = trace_probe_append(&tk->tp, &to->tp); | |
608 | if (ret) | |
609 | return ret; | |
610 | ||
611 | /* Register k*probe */ | |
612 | ret = __register_trace_kprobe(tk); | |
613 | if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) { | |
614 | pr_warn("This probe might be able to register after target module is loaded. Continue.\n"); | |
615 | ret = 0; | |
616 | } | |
617 | ||
618 | if (ret) | |
619 | trace_probe_unlink(&tk->tp); | |
620 | else | |
621 | dyn_event_add(&tk->devent); | |
622 | ||
623 | return ret; | |
624 | } | |
625 | ||
413d37d1 | 626 | /* Register a trace_probe and probe_event */ |
c31ffb3f | 627 | static int register_trace_kprobe(struct trace_kprobe *tk) |
413d37d1 | 628 | { |
c31ffb3f | 629 | struct trace_kprobe *old_tk; |
413d37d1 MH |
630 | int ret; |
631 | ||
6212dd29 | 632 | mutex_lock(&event_mutex); |
413d37d1 | 633 | |
b55ce203 MH |
634 | old_tk = find_trace_kprobe(trace_probe_name(&tk->tp), |
635 | trace_probe_group_name(&tk->tp)); | |
c31ffb3f | 636 | if (old_tk) { |
ca89bc07 MH |
637 | if (trace_kprobe_is_return(tk) != trace_kprobe_is_return(old_tk)) { |
638 | trace_probe_log_set_index(0); | |
639 | trace_probe_log_err(0, DIFF_PROBE_TYPE); | |
640 | ret = -EEXIST; | |
641 | } else { | |
fe60b0ce | 642 | ret = append_trace_kprobe(tk, old_tk); |
ca89bc07 MH |
643 | } |
644 | goto end; | |
2d5e067e | 645 | } |
61424318 MH |
646 | |
647 | /* Register new event */ | |
c31ffb3f | 648 | ret = register_kprobe_event(tk); |
2d5e067e | 649 | if (ret) { |
a395d6a7 | 650 | pr_warn("Failed to register probe event(%d)\n", ret); |
2d5e067e MH |
651 | goto end; |
652 | } | |
653 | ||
61424318 | 654 | /* Register k*probe */ |
c31ffb3f | 655 | ret = __register_trace_kprobe(tk); |
59158ec4 MH |
656 | if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) { |
657 | pr_warn("This probe might be able to register after target module is loaded. Continue.\n"); | |
658 | ret = 0; | |
659 | } | |
660 | ||
61424318 | 661 | if (ret < 0) |
c31ffb3f | 662 | unregister_kprobe_event(tk); |
61424318 | 663 | else |
6212dd29 | 664 | dyn_event_add(&tk->devent); |
61424318 | 665 | |
413d37d1 | 666 | end: |
6212dd29 | 667 | mutex_unlock(&event_mutex); |
413d37d1 MH |
668 | return ret; |
669 | } | |
670 | ||
61424318 | 671 | /* Module notifier call back, checking event on the module */ |
c31ffb3f | 672 | static int trace_kprobe_module_callback(struct notifier_block *nb, |
61424318 MH |
673 | unsigned long val, void *data) |
674 | { | |
675 | struct module *mod = data; | |
6212dd29 | 676 | struct dyn_event *pos; |
c31ffb3f | 677 | struct trace_kprobe *tk; |
61424318 MH |
678 | int ret; |
679 | ||
680 | if (val != MODULE_STATE_COMING) | |
681 | return NOTIFY_DONE; | |
682 | ||
683 | /* Update probes on coming module */ | |
6212dd29 MH |
684 | mutex_lock(&event_mutex); |
685 | for_each_trace_kprobe(tk, pos) { | |
c31ffb3f | 686 | if (trace_kprobe_within_module(tk, mod)) { |
02ca1521 | 687 | /* Don't need to check busy - this should have gone. */ |
c31ffb3f NK |
688 | __unregister_trace_kprobe(tk); |
689 | ret = __register_trace_kprobe(tk); | |
61424318 | 690 | if (ret) |
a395d6a7 | 691 | pr_warn("Failed to re-register probe %s on %s: %d\n", |
b55ce203 | 692 | trace_probe_name(&tk->tp), |
f3d36426 | 693 | module_name(mod), ret); |
61424318 MH |
694 | } |
695 | } | |
6212dd29 | 696 | mutex_unlock(&event_mutex); |
61424318 MH |
697 | |
698 | return NOTIFY_DONE; | |
699 | } | |
700 | ||
c31ffb3f NK |
701 | static struct notifier_block trace_kprobe_module_nb = { |
702 | .notifier_call = trace_kprobe_module_callback, | |
61424318 MH |
703 | .priority = 1 /* Invoked after kprobe module callback */ |
704 | }; | |
705 | ||
fca18a47 NR |
706 | /* Convert certain expected symbols into '_' when generating event names */ |
707 | static inline void sanitize_event_name(char *name) | |
708 | { | |
709 | while (*name++ != '\0') | |
710 | if (*name == ':' || *name == '.') | |
711 | *name = '_'; | |
712 | } | |
713 | ||
d262271d | 714 | static int __trace_kprobe_create(int argc, const char *argv[]) |
413d37d1 MH |
715 | { |
716 | /* | |
717 | * Argument syntax: | |
696ced4f AC |
718 | * - Add kprobe: |
719 | * p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS] | |
720 | * - Add kretprobe: | |
721 | * r[MAXACTIVE][:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS] | |
4725cd89 MH |
722 | * Or |
723 | * p:[GRP/]EVENT] [MOD:]KSYM[+0]%return [FETCHARGS] | |
724 | * | |
413d37d1 | 725 | * Fetch args: |
2e06ff63 MH |
726 | * $retval : fetch return value |
727 | * $stack : fetch stack address | |
728 | * $stackN : fetch Nth of stack (N:0-) | |
35abb67d | 729 | * $comm : fetch current task comm |
413d37d1 MH |
730 | * @ADDR : fetch memory at ADDR (ADDR should be in kernel) |
731 | * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) | |
732 | * %REG : fetch register REG | |
93ccae7a | 733 | * Dereferencing memory fetch: |
413d37d1 | 734 | * +|-offs(ARG) : fetch memory at ARG +|- offs address. |
eca0d916 MH |
735 | * Alias name of args: |
736 | * NAME=FETCHARG : set NAME as alias of FETCHARG. | |
93ccae7a MH |
737 | * Type of args: |
738 | * FETCHARG:TYPE : use TYPE instead of unsigned long. | |
413d37d1 | 739 | */ |
ab105a4f | 740 | struct trace_kprobe *tk = NULL; |
6212dd29 MH |
741 | int i, len, ret = 0; |
742 | bool is_return = false; | |
743 | char *symbol = NULL, *tmp = NULL; | |
744 | const char *event = NULL, *group = KPROBE_EVENT_SYSTEM; | |
696ced4f | 745 | int maxactive = 0; |
c5d343b6 | 746 | long offset = 0; |
413d37d1 | 747 | void *addr = NULL; |
4a846b44 | 748 | char buf[MAX_EVENT_NAME_LEN]; |
a1303af5 | 749 | unsigned int flags = TPARG_FL_KERNEL; |
413d37d1 | 750 | |
8b05a3a7 AR |
751 | switch (argv[0][0]) { |
752 | case 'r': | |
3a6b7666 | 753 | is_return = true; |
8b05a3a7 AR |
754 | break; |
755 | case 'p': | |
756 | break; | |
757 | default: | |
758 | return -ECANCELED; | |
759 | } | |
760 | if (argc < 2) | |
6212dd29 | 761 | return -ECANCELED; |
413d37d1 | 762 | |
ab105a4f MH |
763 | trace_probe_log_init("trace_kprobe", argc, argv); |
764 | ||
696ced4f | 765 | event = strchr(&argv[0][1], ':'); |
6212dd29 | 766 | if (event) |
696ced4f | 767 | event++; |
6212dd29 | 768 | |
287c038c MH |
769 | if (isdigit(argv[0][1])) { |
770 | if (!is_return) { | |
ab105a4f MH |
771 | trace_probe_log_err(1, MAXACT_NO_KPROBE); |
772 | goto parse_error; | |
287c038c | 773 | } |
6212dd29 MH |
774 | if (event) |
775 | len = event - &argv[0][1] - 1; | |
776 | else | |
777 | len = strlen(&argv[0][1]); | |
ab105a4f MH |
778 | if (len > MAX_EVENT_NAME_LEN - 1) { |
779 | trace_probe_log_err(1, BAD_MAXACT); | |
780 | goto parse_error; | |
781 | } | |
6212dd29 MH |
782 | memcpy(buf, &argv[0][1], len); |
783 | buf[len] = '\0'; | |
784 | ret = kstrtouint(buf, 0, &maxactive); | |
287c038c | 785 | if (ret || !maxactive) { |
ab105a4f MH |
786 | trace_probe_log_err(1, BAD_MAXACT); |
787 | goto parse_error; | |
696ced4f AC |
788 | } |
789 | /* kretprobes instances are iterated over via a list. The | |
790 | * maximum should stay reasonable. | |
791 | */ | |
792 | if (maxactive > KRETPROBE_MAXACTIVE_MAX) { | |
ab105a4f MH |
793 | trace_probe_log_err(1, MAXACT_TOO_BIG); |
794 | goto parse_error; | |
696ced4f AC |
795 | } |
796 | } | |
797 | ||
9e52b325 SD |
798 | /* try to parse an address. if that fails, try to read the |
799 | * input as a symbol. */ | |
800 | if (kstrtoul(argv[1], 0, (unsigned long *)&addr)) { | |
ab105a4f | 801 | trace_probe_log_set_index(1); |
6212dd29 | 802 | /* Check whether uprobe event specified */ |
ab105a4f MH |
803 | if (strchr(argv[1], '/') && strchr(argv[1], ':')) { |
804 | ret = -ECANCELED; | |
805 | goto error; | |
806 | } | |
413d37d1 | 807 | /* a symbol specified */ |
6212dd29 MH |
808 | symbol = kstrdup(argv[1], GFP_KERNEL); |
809 | if (!symbol) | |
810 | return -ENOMEM; | |
4725cd89 MH |
811 | |
812 | tmp = strchr(symbol, '%'); | |
813 | if (tmp) { | |
814 | if (!strcmp(tmp, "%return")) { | |
815 | *tmp = '\0'; | |
816 | is_return = true; | |
817 | } else { | |
818 | trace_probe_log_err(tmp - symbol, BAD_ADDR_SUFFIX); | |
819 | goto parse_error; | |
820 | } | |
821 | } | |
822 | ||
413d37d1 | 823 | /* TODO: support .init module functions */ |
8ab83f56 | 824 | ret = traceprobe_split_symbol_offset(symbol, &offset); |
c5d343b6 | 825 | if (ret || offset < 0 || offset > UINT_MAX) { |
ab105a4f MH |
826 | trace_probe_log_err(0, BAD_PROBE_ADDR); |
827 | goto parse_error; | |
e63cc239 | 828 | } |
4725cd89 MH |
829 | if (is_return) |
830 | flags |= TPARG_FL_RETURN; | |
97c753e6 MH |
831 | ret = kprobe_on_func_entry(NULL, symbol, offset); |
832 | if (ret == 0) | |
a1303af5 | 833 | flags |= TPARG_FL_FENTRY; |
97c753e6 MH |
834 | /* Defer the ENOENT case until register kprobe */ |
835 | if (ret == -EINVAL && is_return) { | |
ab105a4f MH |
836 | trace_probe_log_err(0, BAD_RETPROBE); |
837 | goto parse_error; | |
e63cc239 | 838 | } |
413d37d1 MH |
839 | } |
840 | ||
ab105a4f | 841 | trace_probe_log_set_index(0); |
6212dd29 | 842 | if (event) { |
ab105a4f MH |
843 | ret = traceprobe_parse_event_name(&event, &group, buf, |
844 | event - argv[0]); | |
6212dd29 | 845 | if (ret) |
ab105a4f | 846 | goto parse_error; |
6212dd29 | 847 | } else { |
4263565d | 848 | /* Make a new event name */ |
4263565d | 849 | if (symbol) |
6f3cf440 | 850 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", |
4263565d MH |
851 | is_return ? 'r' : 'p', symbol, offset); |
852 | else | |
6f3cf440 | 853 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p", |
4263565d | 854 | is_return ? 'r' : 'p', addr); |
fca18a47 | 855 | sanitize_event_name(buf); |
4a846b44 MH |
856 | event = buf; |
857 | } | |
6212dd29 MH |
858 | |
859 | /* setup a probe */ | |
696ced4f | 860 | tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive, |
ab105a4f | 861 | argc - 2, is_return); |
c31ffb3f | 862 | if (IS_ERR(tk)) { |
6212dd29 | 863 | ret = PTR_ERR(tk); |
ab105a4f | 864 | /* This must return -ENOMEM, else there is a bug */ |
a039480e | 865 | WARN_ON_ONCE(ret != -ENOMEM); |
ab105a4f | 866 | goto out; /* We know tk is not allocated */ |
e63cc239 | 867 | } |
ab105a4f | 868 | argc -= 2; argv += 2; |
413d37d1 | 869 | |
413d37d1 | 870 | /* parse arguments */ |
a82378d8 | 871 | for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { |
6212dd29 MH |
872 | tmp = kstrdup(argv[i], GFP_KERNEL); |
873 | if (!tmp) { | |
ba8665d7 | 874 | ret = -ENOMEM; |
413d37d1 MH |
875 | goto error; |
876 | } | |
da34634f | 877 | |
ab105a4f | 878 | trace_probe_log_set_index(i + 2); |
6212dd29 MH |
879 | ret = traceprobe_parse_probe_arg(&tk->tp, i, tmp, flags); |
880 | kfree(tmp); | |
d00bbea9 | 881 | if (ret) |
ab105a4f | 882 | goto error; /* This can be -ENOMEM */ |
413d37d1 | 883 | } |
413d37d1 | 884 | |
f730e0f2 MH |
885 | ret = traceprobe_set_print_fmt(&tk->tp, is_return); |
886 | if (ret < 0) | |
887 | goto error; | |
888 | ||
c31ffb3f | 889 | ret = register_trace_kprobe(tk); |
ab105a4f MH |
890 | if (ret) { |
891 | trace_probe_log_set_index(1); | |
892 | if (ret == -EILSEQ) | |
893 | trace_probe_log_err(0, BAD_INSN_BNDRY); | |
894 | else if (ret == -ENOENT) | |
895 | trace_probe_log_err(0, BAD_PROBE_ADDR); | |
ca89bc07 | 896 | else if (ret != -ENOMEM && ret != -EEXIST) |
ab105a4f | 897 | trace_probe_log_err(0, FAIL_REG_PROBE); |
413d37d1 | 898 | goto error; |
ab105a4f MH |
899 | } |
900 | ||
6212dd29 | 901 | out: |
ab105a4f | 902 | trace_probe_log_clear(); |
6212dd29 MH |
903 | kfree(symbol); |
904 | return ret; | |
413d37d1 | 905 | |
ab105a4f MH |
906 | parse_error: |
907 | ret = -EINVAL; | |
413d37d1 | 908 | error: |
c31ffb3f | 909 | free_trace_kprobe(tk); |
6212dd29 | 910 | goto out; |
413d37d1 MH |
911 | } |
912 | ||
d262271d MH |
913 | static int trace_kprobe_create(const char *raw_command) |
914 | { | |
915 | return trace_probe_create(raw_command, __trace_kprobe_create); | |
916 | } | |
917 | ||
918 | static int create_or_delete_trace_kprobe(const char *raw_command) | |
413d37d1 | 919 | { |
6212dd29 | 920 | int ret; |
02ca1521 | 921 | |
d262271d MH |
922 | if (raw_command[0] == '-') |
923 | return dyn_event_release(raw_command, &trace_kprobe_ops); | |
413d37d1 | 924 | |
d262271d | 925 | ret = trace_kprobe_create(raw_command); |
6212dd29 | 926 | return ret == -ECANCELED ? -EINVAL : ret; |
413d37d1 MH |
927 | } |
928 | ||
29a15481 | 929 | static int trace_kprobe_run_command(struct dynevent_cmd *cmd) |
2a588dd1 | 930 | { |
d262271d | 931 | return create_or_delete_trace_kprobe(cmd->seq.buffer); |
2a588dd1 TZ |
932 | } |
933 | ||
934 | /** | |
935 | * kprobe_event_cmd_init - Initialize a kprobe event command object | |
936 | * @cmd: A pointer to the dynevent_cmd struct representing the new event | |
937 | * @buf: A pointer to the buffer used to build the command | |
938 | * @maxlen: The length of the buffer passed in @buf | |
939 | * | |
940 | * Initialize a synthetic event command object. Use this before | |
941 | * calling any of the other kprobe_event functions. | |
942 | */ | |
943 | void kprobe_event_cmd_init(struct dynevent_cmd *cmd, char *buf, int maxlen) | |
944 | { | |
945 | dynevent_cmd_init(cmd, buf, maxlen, DYNEVENT_TYPE_KPROBE, | |
29a15481 | 946 | trace_kprobe_run_command); |
2a588dd1 TZ |
947 | } |
948 | EXPORT_SYMBOL_GPL(kprobe_event_cmd_init); | |
949 | ||
950 | /** | |
951 | * __kprobe_event_gen_cmd_start - Generate a kprobe event command from arg list | |
952 | * @cmd: A pointer to the dynevent_cmd struct representing the new event | |
953 | * @name: The name of the kprobe event | |
954 | * @loc: The location of the kprobe event | |
955 | * @kretprobe: Is this a return probe? | |
956 | * @args: Variable number of arg (pairs), one pair for each field | |
957 | * | |
958 | * NOTE: Users normally won't want to call this function directly, but | |
959 | * rather use the kprobe_event_gen_cmd_start() wrapper, which automatically | |
960 | * adds a NULL to the end of the arg list. If this function is used | |
961 | * directly, make sure the last arg in the variable arg list is NULL. | |
962 | * | |
963 | * Generate a kprobe event command to be executed by | |
964 | * kprobe_event_gen_cmd_end(). This function can be used to generate the | |
965 | * complete command or only the first part of it; in the latter case, | |
966 | * kprobe_event_add_fields() can be used to add more fields following this. | |
967 | * | |
5b4dcd2d MH |
968 | * Unlikely the synth_event_gen_cmd_start(), @loc must be specified. This |
969 | * returns -EINVAL if @loc == NULL. | |
970 | * | |
2a588dd1 TZ |
971 | * Return: 0 if successful, error otherwise. |
972 | */ | |
973 | int __kprobe_event_gen_cmd_start(struct dynevent_cmd *cmd, bool kretprobe, | |
974 | const char *name, const char *loc, ...) | |
975 | { | |
976 | char buf[MAX_EVENT_NAME_LEN]; | |
977 | struct dynevent_arg arg; | |
978 | va_list args; | |
979 | int ret; | |
980 | ||
981 | if (cmd->type != DYNEVENT_TYPE_KPROBE) | |
982 | return -EINVAL; | |
983 | ||
5b4dcd2d MH |
984 | if (!loc) |
985 | return -EINVAL; | |
986 | ||
2a588dd1 TZ |
987 | if (kretprobe) |
988 | snprintf(buf, MAX_EVENT_NAME_LEN, "r:kprobes/%s", name); | |
989 | else | |
990 | snprintf(buf, MAX_EVENT_NAME_LEN, "p:kprobes/%s", name); | |
991 | ||
992 | ret = dynevent_str_add(cmd, buf); | |
993 | if (ret) | |
994 | return ret; | |
995 | ||
74403b6c | 996 | dynevent_arg_init(&arg, 0); |
2a588dd1 | 997 | arg.str = loc; |
74403b6c | 998 | ret = dynevent_arg_add(cmd, &arg, NULL); |
2a588dd1 TZ |
999 | if (ret) |
1000 | return ret; | |
1001 | ||
1002 | va_start(args, loc); | |
1003 | for (;;) { | |
1004 | const char *field; | |
1005 | ||
1006 | field = va_arg(args, const char *); | |
1007 | if (!field) | |
1008 | break; | |
1009 | ||
1010 | if (++cmd->n_fields > MAX_TRACE_ARGS) { | |
1011 | ret = -EINVAL; | |
1012 | break; | |
1013 | } | |
1014 | ||
1015 | arg.str = field; | |
74403b6c | 1016 | ret = dynevent_arg_add(cmd, &arg, NULL); |
2a588dd1 TZ |
1017 | if (ret) |
1018 | break; | |
1019 | } | |
1020 | va_end(args); | |
1021 | ||
1022 | return ret; | |
1023 | } | |
1024 | EXPORT_SYMBOL_GPL(__kprobe_event_gen_cmd_start); | |
1025 | ||
1026 | /** | |
1027 | * __kprobe_event_add_fields - Add probe fields to a kprobe command from arg list | |
1028 | * @cmd: A pointer to the dynevent_cmd struct representing the new event | |
1029 | * @args: Variable number of arg (pairs), one pair for each field | |
1030 | * | |
1031 | * NOTE: Users normally won't want to call this function directly, but | |
1032 | * rather use the kprobe_event_add_fields() wrapper, which | |
1033 | * automatically adds a NULL to the end of the arg list. If this | |
1034 | * function is used directly, make sure the last arg in the variable | |
1035 | * arg list is NULL. | |
1036 | * | |
1037 | * Add probe fields to an existing kprobe command using a variable | |
1038 | * list of args. Fields are added in the same order they're listed. | |
1039 | * | |
1040 | * Return: 0 if successful, error otherwise. | |
1041 | */ | |
1042 | int __kprobe_event_add_fields(struct dynevent_cmd *cmd, ...) | |
1043 | { | |
1044 | struct dynevent_arg arg; | |
1045 | va_list args; | |
10f129cb | 1046 | int ret = 0; |
2a588dd1 TZ |
1047 | |
1048 | if (cmd->type != DYNEVENT_TYPE_KPROBE) | |
1049 | return -EINVAL; | |
1050 | ||
74403b6c | 1051 | dynevent_arg_init(&arg, 0); |
2a588dd1 TZ |
1052 | |
1053 | va_start(args, cmd); | |
1054 | for (;;) { | |
1055 | const char *field; | |
1056 | ||
1057 | field = va_arg(args, const char *); | |
1058 | if (!field) | |
1059 | break; | |
1060 | ||
1061 | if (++cmd->n_fields > MAX_TRACE_ARGS) { | |
1062 | ret = -EINVAL; | |
1063 | break; | |
1064 | } | |
1065 | ||
1066 | arg.str = field; | |
74403b6c | 1067 | ret = dynevent_arg_add(cmd, &arg, NULL); |
2a588dd1 TZ |
1068 | if (ret) |
1069 | break; | |
1070 | } | |
1071 | va_end(args); | |
1072 | ||
1073 | return ret; | |
1074 | } | |
1075 | EXPORT_SYMBOL_GPL(__kprobe_event_add_fields); | |
1076 | ||
1077 | /** | |
1078 | * kprobe_event_delete - Delete a kprobe event | |
1079 | * @name: The name of the kprobe event to delete | |
1080 | * | |
1081 | * Delete a kprobe event with the give @name from kernel code rather | |
1082 | * than directly from the command line. | |
1083 | * | |
1084 | * Return: 0 if successful, error otherwise. | |
1085 | */ | |
1086 | int kprobe_event_delete(const char *name) | |
1087 | { | |
1088 | char buf[MAX_EVENT_NAME_LEN]; | |
1089 | ||
1090 | snprintf(buf, MAX_EVENT_NAME_LEN, "-:%s", name); | |
1091 | ||
d262271d | 1092 | return create_or_delete_trace_kprobe(buf); |
2a588dd1 TZ |
1093 | } |
1094 | EXPORT_SYMBOL_GPL(kprobe_event_delete); | |
1095 | ||
6212dd29 | 1096 | static int trace_kprobe_release(struct dyn_event *ev) |
413d37d1 | 1097 | { |
6212dd29 MH |
1098 | struct trace_kprobe *tk = to_trace_kprobe(ev); |
1099 | int ret = unregister_trace_kprobe(tk); | |
413d37d1 | 1100 | |
6212dd29 MH |
1101 | if (!ret) |
1102 | free_trace_kprobe(tk); | |
1103 | return ret; | |
413d37d1 MH |
1104 | } |
1105 | ||
6212dd29 | 1106 | static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev) |
413d37d1 | 1107 | { |
6212dd29 | 1108 | struct trace_kprobe *tk = to_trace_kprobe(ev); |
93ccae7a | 1109 | int i; |
413d37d1 | 1110 | |
fa6f0cc7 | 1111 | seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p'); |
6a13a0d7 MH |
1112 | if (trace_kprobe_is_return(tk) && tk->rp.maxactive) |
1113 | seq_printf(m, "%d", tk->rp.maxactive); | |
b55ce203 MH |
1114 | seq_printf(m, ":%s/%s", trace_probe_group_name(&tk->tp), |
1115 | trace_probe_name(&tk->tp)); | |
413d37d1 | 1116 | |
c31ffb3f NK |
1117 | if (!tk->symbol) |
1118 | seq_printf(m, " 0x%p", tk->rp.kp.addr); | |
1119 | else if (tk->rp.kp.offset) | |
1120 | seq_printf(m, " %s+%u", trace_kprobe_symbol(tk), | |
1121 | tk->rp.kp.offset); | |
413d37d1 | 1122 | else |
c31ffb3f | 1123 | seq_printf(m, " %s", trace_kprobe_symbol(tk)); |
413d37d1 | 1124 | |
c31ffb3f NK |
1125 | for (i = 0; i < tk->tp.nr_args; i++) |
1126 | seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm); | |
fa6f0cc7 | 1127 | seq_putc(m, '\n'); |
93ccae7a | 1128 | |
413d37d1 MH |
1129 | return 0; |
1130 | } | |
1131 | ||
6212dd29 MH |
1132 | static int probes_seq_show(struct seq_file *m, void *v) |
1133 | { | |
1134 | struct dyn_event *ev = v; | |
1135 | ||
1136 | if (!is_trace_kprobe(ev)) | |
1137 | return 0; | |
1138 | ||
1139 | return trace_kprobe_show(m, ev); | |
1140 | } | |
1141 | ||
413d37d1 | 1142 | static const struct seq_operations probes_seq_op = { |
6212dd29 MH |
1143 | .start = dyn_event_seq_start, |
1144 | .next = dyn_event_seq_next, | |
1145 | .stop = dyn_event_seq_stop, | |
413d37d1 MH |
1146 | .show = probes_seq_show |
1147 | }; | |
1148 | ||
1149 | static int probes_open(struct inode *inode, struct file *file) | |
1150 | { | |
02ca1521 MH |
1151 | int ret; |
1152 | ||
17911ff3 SRV |
1153 | ret = security_locked_down(LOCKDOWN_TRACEFS); |
1154 | if (ret) | |
1155 | return ret; | |
1156 | ||
02ca1521 | 1157 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
6212dd29 | 1158 | ret = dyn_events_release_all(&trace_kprobe_ops); |
02ca1521 MH |
1159 | if (ret < 0) |
1160 | return ret; | |
1161 | } | |
413d37d1 MH |
1162 | |
1163 | return seq_open(file, &probes_seq_op); | |
1164 | } | |
1165 | ||
413d37d1 MH |
1166 | static ssize_t probes_write(struct file *file, const char __user *buffer, |
1167 | size_t count, loff_t *ppos) | |
1168 | { | |
7e465baa | 1169 | return trace_parse_run_command(file, buffer, count, ppos, |
6212dd29 | 1170 | create_or_delete_trace_kprobe); |
413d37d1 MH |
1171 | } |
1172 | ||
1173 | static const struct file_operations kprobe_events_ops = { | |
1174 | .owner = THIS_MODULE, | |
1175 | .open = probes_open, | |
1176 | .read = seq_read, | |
1177 | .llseek = seq_lseek, | |
1178 | .release = seq_release, | |
1179 | .write = probes_write, | |
1180 | }; | |
1181 | ||
cd7e7bd5 MH |
1182 | /* Probes profiling interfaces */ |
1183 | static int probes_profile_seq_show(struct seq_file *m, void *v) | |
1184 | { | |
6212dd29 MH |
1185 | struct dyn_event *ev = v; |
1186 | struct trace_kprobe *tk; | |
cd7e7bd5 | 1187 | |
6212dd29 MH |
1188 | if (!is_trace_kprobe(ev)) |
1189 | return 0; | |
cd7e7bd5 | 1190 | |
6212dd29 | 1191 | tk = to_trace_kprobe(ev); |
de7b2973 | 1192 | seq_printf(m, " %-44s %15lu %15lu\n", |
b55ce203 | 1193 | trace_probe_name(&tk->tp), |
f18f97ac | 1194 | trace_kprobe_nhit(tk), |
c31ffb3f | 1195 | tk->rp.kp.nmissed); |
cd7e7bd5 MH |
1196 | |
1197 | return 0; | |
1198 | } | |
1199 | ||
1200 | static const struct seq_operations profile_seq_op = { | |
6212dd29 MH |
1201 | .start = dyn_event_seq_start, |
1202 | .next = dyn_event_seq_next, | |
1203 | .stop = dyn_event_seq_stop, | |
cd7e7bd5 MH |
1204 | .show = probes_profile_seq_show |
1205 | }; | |
1206 | ||
1207 | static int profile_open(struct inode *inode, struct file *file) | |
1208 | { | |
17911ff3 SRV |
1209 | int ret; |
1210 | ||
1211 | ret = security_locked_down(LOCKDOWN_TRACEFS); | |
1212 | if (ret) | |
1213 | return ret; | |
1214 | ||
cd7e7bd5 MH |
1215 | return seq_open(file, &profile_seq_op); |
1216 | } | |
1217 | ||
1218 | static const struct file_operations kprobe_profile_ops = { | |
1219 | .owner = THIS_MODULE, | |
1220 | .open = profile_open, | |
1221 | .read = seq_read, | |
1222 | .llseek = seq_lseek, | |
1223 | .release = seq_release, | |
1224 | }; | |
1225 | ||
53305928 MH |
1226 | /* Kprobe specific fetch functions */ |
1227 | ||
9de1fec5 CH |
1228 | /* Return the length of string -- including null terminal byte */ |
1229 | static nokprobe_inline int | |
1230 | fetch_store_strlen_user(unsigned long addr) | |
1231 | { | |
1232 | const void __user *uaddr = (__force const void __user *)addr; | |
1233 | ||
1234 | return strnlen_user_nofault(uaddr, MAX_STRING_SIZE); | |
1235 | } | |
1236 | ||
53305928 | 1237 | /* Return the length of string -- including null terminal byte */ |
9178412d MH |
1238 | static nokprobe_inline int |
1239 | fetch_store_strlen(unsigned long addr) | |
53305928 | 1240 | { |
53305928 MH |
1241 | int ret, len = 0; |
1242 | u8 c; | |
1243 | ||
9de1fec5 CH |
1244 | #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE |
1245 | if (addr < TASK_SIZE) | |
1246 | return fetch_store_strlen_user(addr); | |
1247 | #endif | |
1248 | ||
53305928 | 1249 | do { |
fe557319 | 1250 | ret = copy_from_kernel_nofault(&c, (u8 *)addr + len, 1); |
53305928 MH |
1251 | len++; |
1252 | } while (c && ret == 0 && len < MAX_STRING_SIZE); | |
1253 | ||
9178412d | 1254 | return (ret < 0) ? ret : len; |
53305928 MH |
1255 | } |
1256 | ||
1257 | /* | |
9de1fec5 CH |
1258 | * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf |
1259 | * with max length and relative data location. | |
53305928 | 1260 | */ |
9178412d | 1261 | static nokprobe_inline int |
9de1fec5 | 1262 | fetch_store_string_user(unsigned long addr, void *dest, void *base) |
53305928 | 1263 | { |
9de1fec5 | 1264 | const void __user *uaddr = (__force const void __user *)addr; |
9178412d | 1265 | int maxlen = get_loc_len(*(u32 *)dest); |
88903c46 | 1266 | void *__dest; |
53305928 MH |
1267 | long ret; |
1268 | ||
9178412d MH |
1269 | if (unlikely(!maxlen)) |
1270 | return -ENOMEM; | |
88903c46 MH |
1271 | |
1272 | __dest = get_loc_data(dest, base); | |
1273 | ||
9de1fec5 | 1274 | ret = strncpy_from_user_nofault(__dest, uaddr, maxlen); |
88903c46 MH |
1275 | if (ret >= 0) |
1276 | *(u32 *)dest = make_data_loc(ret, __dest - base); | |
1277 | ||
1278 | return ret; | |
1279 | } | |
53305928 | 1280 | |
88903c46 | 1281 | /* |
9de1fec5 CH |
1282 | * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max |
1283 | * length and relative data location. | |
88903c46 MH |
1284 | */ |
1285 | static nokprobe_inline int | |
9de1fec5 | 1286 | fetch_store_string(unsigned long addr, void *dest, void *base) |
88903c46 | 1287 | { |
88903c46 MH |
1288 | int maxlen = get_loc_len(*(u32 *)dest); |
1289 | void *__dest; | |
1290 | long ret; | |
1291 | ||
9de1fec5 CH |
1292 | #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE |
1293 | if ((unsigned long)addr < TASK_SIZE) | |
1294 | return fetch_store_string_user(addr, dest, base); | |
1295 | #endif | |
1296 | ||
88903c46 MH |
1297 | if (unlikely(!maxlen)) |
1298 | return -ENOMEM; | |
1299 | ||
1300 | __dest = get_loc_data(dest, base); | |
1301 | ||
9de1fec5 CH |
1302 | /* |
1303 | * Try to get string again, since the string can be changed while | |
1304 | * probing. | |
1305 | */ | |
1306 | ret = strncpy_from_kernel_nofault(__dest, (void *)addr, maxlen); | |
9178412d | 1307 | if (ret >= 0) |
88903c46 MH |
1308 | *(u32 *)dest = make_data_loc(ret, __dest - base); |
1309 | ||
9178412d | 1310 | return ret; |
53305928 MH |
1311 | } |
1312 | ||
e65f7ae7 MH |
1313 | static nokprobe_inline int |
1314 | probe_mem_read_user(void *dest, void *src, size_t size) | |
1315 | { | |
539b75b2 MH |
1316 | const void __user *uaddr = (__force const void __user *)src; |
1317 | ||
c0ee37e8 | 1318 | return copy_from_user_nofault(dest, uaddr, size); |
e65f7ae7 MH |
1319 | } |
1320 | ||
9de1fec5 CH |
1321 | static nokprobe_inline int |
1322 | probe_mem_read(void *dest, void *src, size_t size) | |
1323 | { | |
1324 | #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE | |
1325 | if ((unsigned long)src < TASK_SIZE) | |
1326 | return probe_mem_read_user(dest, src, size); | |
1327 | #endif | |
fe557319 | 1328 | return copy_from_kernel_nofault(dest, src, size); |
9de1fec5 CH |
1329 | } |
1330 | ||
53305928 MH |
1331 | /* Note that we don't verify it, since the code does not come from user space */ |
1332 | static int | |
1333 | process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest, | |
9178412d | 1334 | void *base) |
53305928 MH |
1335 | { |
1336 | unsigned long val; | |
53305928 | 1337 | |
a6682814 | 1338 | retry: |
53305928 MH |
1339 | /* 1st stage: get value from context */ |
1340 | switch (code->op) { | |
1341 | case FETCH_OP_REG: | |
1342 | val = regs_get_register(regs, code->param); | |
1343 | break; | |
1344 | case FETCH_OP_STACK: | |
1345 | val = regs_get_kernel_stack_nth(regs, code->param); | |
1346 | break; | |
1347 | case FETCH_OP_STACKP: | |
1348 | val = kernel_stack_pointer(regs); | |
1349 | break; | |
1350 | case FETCH_OP_RETVAL: | |
1351 | val = regs_return_value(regs); | |
1352 | break; | |
1353 | case FETCH_OP_IMM: | |
1354 | val = code->immediate; | |
1355 | break; | |
1356 | case FETCH_OP_COMM: | |
1357 | val = (unsigned long)current->comm; | |
1358 | break; | |
a42e3c4d MH |
1359 | case FETCH_OP_DATA: |
1360 | val = (unsigned long)code->data; | |
1361 | break; | |
a1303af5 MH |
1362 | #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API |
1363 | case FETCH_OP_ARG: | |
1364 | val = regs_get_kernel_argument(regs, code->param); | |
1365 | break; | |
1366 | #endif | |
a6682814 MH |
1367 | case FETCH_NOP_SYMBOL: /* Ignore a place holder */ |
1368 | code++; | |
1369 | goto retry; | |
53305928 MH |
1370 | default: |
1371 | return -EILSEQ; | |
1372 | } | |
1373 | code++; | |
1374 | ||
9b960a38 | 1375 | return process_fetch_insn_bottom(code, val, dest, base); |
53305928 MH |
1376 | } |
1377 | NOKPROBE_SYMBOL(process_fetch_insn) | |
1378 | ||
413d37d1 | 1379 | /* Kprobe handler */ |
3da0f180 | 1380 | static nokprobe_inline void |
c31ffb3f | 1381 | __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs, |
7f1d2f82 | 1382 | struct trace_event_file *trace_file) |
413d37d1 | 1383 | { |
93ccae7a | 1384 | struct kprobe_trace_entry_head *entry; |
e3dc9f89 | 1385 | struct trace_event_call *call = trace_probe_event_call(&tk->tp); |
8cfcf155 MH |
1386 | struct trace_event_buffer fbuffer; |
1387 | int dsize; | |
413d37d1 | 1388 | |
7f1d2f82 | 1389 | WARN_ON(call != trace_file->event_call); |
41a7dd42 | 1390 | |
09a5059a | 1391 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 1392 | return; |
b8820084 | 1393 | |
36590c50 | 1394 | fbuffer.trace_ctx = tracing_gen_ctx(); |
8cfcf155 | 1395 | fbuffer.trace_file = trace_file; |
413d37d1 | 1396 | |
c31ffb3f | 1397 | dsize = __get_data_size(&tk->tp, regs); |
413d37d1 | 1398 | |
8cfcf155 MH |
1399 | fbuffer.event = |
1400 | trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file, | |
1401 | call->event.type, | |
1402 | sizeof(*entry) + tk->tp.size + dsize, | |
36590c50 | 1403 | fbuffer.trace_ctx); |
8cfcf155 | 1404 | if (!fbuffer.event) |
1e12a4a7 | 1405 | return; |
413d37d1 | 1406 | |
8cfcf155 MH |
1407 | fbuffer.regs = regs; |
1408 | entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); | |
c31ffb3f | 1409 | entry->ip = (unsigned long)tk->rp.kp.addr; |
9178412d | 1410 | store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize); |
413d37d1 | 1411 | |
8cfcf155 | 1412 | trace_event_buffer_commit(&fbuffer); |
413d37d1 MH |
1413 | } |
1414 | ||
3da0f180 | 1415 | static void |
c31ffb3f | 1416 | kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs) |
41a7dd42 | 1417 | { |
b04d52e3 | 1418 | struct event_file_link *link; |
41a7dd42 | 1419 | |
b5f935ee | 1420 | trace_probe_for_each_link_rcu(link, &tk->tp) |
c31ffb3f | 1421 | __kprobe_trace_func(tk, regs, link->file); |
41a7dd42 | 1422 | } |
3da0f180 | 1423 | NOKPROBE_SYMBOL(kprobe_trace_func); |
41a7dd42 | 1424 | |
413d37d1 | 1425 | /* Kretprobe handler */ |
3da0f180 | 1426 | static nokprobe_inline void |
c31ffb3f | 1427 | __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
41a7dd42 | 1428 | struct pt_regs *regs, |
7f1d2f82 | 1429 | struct trace_event_file *trace_file) |
413d37d1 | 1430 | { |
93ccae7a | 1431 | struct kretprobe_trace_entry_head *entry; |
8cfcf155 | 1432 | struct trace_event_buffer fbuffer; |
e3dc9f89 | 1433 | struct trace_event_call *call = trace_probe_event_call(&tk->tp); |
8cfcf155 | 1434 | int dsize; |
413d37d1 | 1435 | |
7f1d2f82 | 1436 | WARN_ON(call != trace_file->event_call); |
41a7dd42 | 1437 | |
09a5059a | 1438 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 1439 | return; |
b8820084 | 1440 | |
36590c50 | 1441 | fbuffer.trace_ctx = tracing_gen_ctx(); |
8cfcf155 | 1442 | fbuffer.trace_file = trace_file; |
413d37d1 | 1443 | |
c31ffb3f | 1444 | dsize = __get_data_size(&tk->tp, regs); |
8cfcf155 MH |
1445 | fbuffer.event = |
1446 | trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file, | |
1447 | call->event.type, | |
1448 | sizeof(*entry) + tk->tp.size + dsize, | |
36590c50 | 1449 | fbuffer.trace_ctx); |
8cfcf155 | 1450 | if (!fbuffer.event) |
1e12a4a7 | 1451 | return; |
413d37d1 | 1452 | |
8cfcf155 MH |
1453 | fbuffer.regs = regs; |
1454 | entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); | |
c31ffb3f | 1455 | entry->func = (unsigned long)tk->rp.kp.addr; |
413d37d1 | 1456 | entry->ret_ip = (unsigned long)ri->ret_addr; |
9178412d | 1457 | store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize); |
413d37d1 | 1458 | |
8cfcf155 | 1459 | trace_event_buffer_commit(&fbuffer); |
413d37d1 MH |
1460 | } |
1461 | ||
3da0f180 | 1462 | static void |
c31ffb3f | 1463 | kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
41a7dd42 MH |
1464 | struct pt_regs *regs) |
1465 | { | |
b04d52e3 | 1466 | struct event_file_link *link; |
41a7dd42 | 1467 | |
b5f935ee | 1468 | trace_probe_for_each_link_rcu(link, &tk->tp) |
c31ffb3f | 1469 | __kretprobe_trace_func(tk, ri, regs, link->file); |
41a7dd42 | 1470 | } |
3da0f180 | 1471 | NOKPROBE_SYMBOL(kretprobe_trace_func); |
41a7dd42 | 1472 | |
413d37d1 | 1473 | /* Event entry printers */ |
b62fdd97 | 1474 | static enum print_line_t |
a9a57763 SR |
1475 | print_kprobe_event(struct trace_iterator *iter, int flags, |
1476 | struct trace_event *event) | |
413d37d1 | 1477 | { |
93ccae7a | 1478 | struct kprobe_trace_entry_head *field; |
413d37d1 | 1479 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1480 | struct trace_probe *tp; |
413d37d1 | 1481 | |
93ccae7a | 1482 | field = (struct kprobe_trace_entry_head *)iter->ent; |
60d53e2c MH |
1483 | tp = trace_probe_primary_from_call( |
1484 | container_of(event, struct trace_event_call, event)); | |
1485 | if (WARN_ON_ONCE(!tp)) | |
1486 | goto out; | |
413d37d1 | 1487 | |
b55ce203 | 1488 | trace_seq_printf(s, "%s: (", trace_probe_name(tp)); |
6e9f23d1 | 1489 | |
413d37d1 | 1490 | if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) |
85224da0 | 1491 | goto out; |
413d37d1 | 1492 | |
85224da0 | 1493 | trace_seq_putc(s, ')'); |
413d37d1 | 1494 | |
56de7630 MH |
1495 | if (print_probe_args(s, tp->args, tp->nr_args, |
1496 | (u8 *)&field[1], field) < 0) | |
1497 | goto out; | |
413d37d1 | 1498 | |
85224da0 SRRH |
1499 | trace_seq_putc(s, '\n'); |
1500 | out: | |
1501 | return trace_handle_return(s); | |
413d37d1 MH |
1502 | } |
1503 | ||
b62fdd97 | 1504 | static enum print_line_t |
a9a57763 SR |
1505 | print_kretprobe_event(struct trace_iterator *iter, int flags, |
1506 | struct trace_event *event) | |
413d37d1 | 1507 | { |
93ccae7a | 1508 | struct kretprobe_trace_entry_head *field; |
413d37d1 | 1509 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1510 | struct trace_probe *tp; |
413d37d1 | 1511 | |
93ccae7a | 1512 | field = (struct kretprobe_trace_entry_head *)iter->ent; |
60d53e2c MH |
1513 | tp = trace_probe_primary_from_call( |
1514 | container_of(event, struct trace_event_call, event)); | |
1515 | if (WARN_ON_ONCE(!tp)) | |
1516 | goto out; | |
413d37d1 | 1517 | |
b55ce203 | 1518 | trace_seq_printf(s, "%s: (", trace_probe_name(tp)); |
6e9f23d1 | 1519 | |
413d37d1 | 1520 | if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) |
85224da0 | 1521 | goto out; |
413d37d1 | 1522 | |
85224da0 | 1523 | trace_seq_puts(s, " <- "); |
413d37d1 MH |
1524 | |
1525 | if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) | |
85224da0 | 1526 | goto out; |
413d37d1 | 1527 | |
85224da0 | 1528 | trace_seq_putc(s, ')'); |
413d37d1 | 1529 | |
56de7630 MH |
1530 | if (print_probe_args(s, tp->args, tp->nr_args, |
1531 | (u8 *)&field[1], field) < 0) | |
1532 | goto out; | |
413d37d1 | 1533 | |
85224da0 | 1534 | trace_seq_putc(s, '\n'); |
413d37d1 | 1535 | |
85224da0 SRRH |
1536 | out: |
1537 | return trace_handle_return(s); | |
413d37d1 MH |
1538 | } |
1539 | ||
413d37d1 | 1540 | |
2425bcb9 | 1541 | static int kprobe_event_define_fields(struct trace_event_call *event_call) |
413d37d1 | 1542 | { |
eeb07b06 | 1543 | int ret; |
93ccae7a | 1544 | struct kprobe_trace_entry_head field; |
60d53e2c MH |
1545 | struct trace_probe *tp; |
1546 | ||
1547 | tp = trace_probe_primary_from_call(event_call); | |
1548 | if (WARN_ON_ONCE(!tp)) | |
1549 | return -ENOENT; | |
413d37d1 | 1550 | |
a703d946 | 1551 | DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); |
c31ffb3f | 1552 | |
60d53e2c | 1553 | return traceprobe_define_arg_fields(event_call, sizeof(field), tp); |
413d37d1 MH |
1554 | } |
1555 | ||
2425bcb9 | 1556 | static int kretprobe_event_define_fields(struct trace_event_call *event_call) |
413d37d1 | 1557 | { |
eeb07b06 | 1558 | int ret; |
93ccae7a | 1559 | struct kretprobe_trace_entry_head field; |
60d53e2c MH |
1560 | struct trace_probe *tp; |
1561 | ||
1562 | tp = trace_probe_primary_from_call(event_call); | |
1563 | if (WARN_ON_ONCE(!tp)) | |
1564 | return -ENOENT; | |
413d37d1 | 1565 | |
a703d946 MH |
1566 | DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); |
1567 | DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); | |
c31ffb3f | 1568 | |
60d53e2c | 1569 | return traceprobe_define_arg_fields(event_call, sizeof(field), tp); |
413d37d1 MH |
1570 | } |
1571 | ||
07b139c8 | 1572 | #ifdef CONFIG_PERF_EVENTS |
e08d1c65 MH |
1573 | |
1574 | /* Kprobe profile handler */ | |
9802d865 | 1575 | static int |
c31ffb3f | 1576 | kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) |
e08d1c65 | 1577 | { |
e3dc9f89 | 1578 | struct trace_event_call *call = trace_probe_event_call(&tk->tp); |
93ccae7a | 1579 | struct kprobe_trace_entry_head *entry; |
1c024eca | 1580 | struct hlist_head *head; |
e09c8614 | 1581 | int size, __size, dsize; |
4ed7c92d | 1582 | int rctx; |
e08d1c65 | 1583 | |
9802d865 | 1584 | if (bpf_prog_array_valid(call)) { |
66665ad2 | 1585 | unsigned long orig_ip = instruction_pointer(regs); |
9802d865 JB |
1586 | int ret; |
1587 | ||
1588 | ret = trace_call_bpf(call, regs); | |
1589 | ||
1590 | /* | |
1591 | * We need to check and see if we modified the pc of the | |
cce188bd MH |
1592 | * pt_regs, and if so return 1 so that we don't do the |
1593 | * single stepping. | |
9802d865 | 1594 | */ |
cce188bd | 1595 | if (orig_ip != instruction_pointer(regs)) |
9802d865 | 1596 | return 1; |
9802d865 JB |
1597 | if (!ret) |
1598 | return 0; | |
1599 | } | |
2541517c | 1600 | |
288e984e ON |
1601 | head = this_cpu_ptr(call->perf_events); |
1602 | if (hlist_empty(head)) | |
9802d865 | 1603 | return 0; |
288e984e | 1604 | |
c31ffb3f NK |
1605 | dsize = __get_data_size(&tk->tp, regs); |
1606 | __size = sizeof(*entry) + tk->tp.size + dsize; | |
74ebb63e MH |
1607 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1608 | size -= sizeof(u32); | |
ce71b9df | 1609 | |
1e1dcd93 | 1610 | entry = perf_trace_buf_alloc(size, NULL, &rctx); |
430ad5a6 | 1611 | if (!entry) |
9802d865 | 1612 | return 0; |
a1a138d0 | 1613 | |
c31ffb3f | 1614 | entry->ip = (unsigned long)tk->rp.kp.addr; |
e09c8614 | 1615 | memset(&entry[1], 0, dsize); |
9178412d | 1616 | store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize); |
1e1dcd93 | 1617 | perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, |
8fd0fbbe | 1618 | head, NULL); |
9802d865 | 1619 | return 0; |
e08d1c65 | 1620 | } |
3da0f180 | 1621 | NOKPROBE_SYMBOL(kprobe_perf_func); |
e08d1c65 MH |
1622 | |
1623 | /* Kretprobe profile handler */ | |
3da0f180 | 1624 | static void |
c31ffb3f | 1625 | kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
2b106aab | 1626 | struct pt_regs *regs) |
e08d1c65 | 1627 | { |
e3dc9f89 | 1628 | struct trace_event_call *call = trace_probe_event_call(&tk->tp); |
93ccae7a | 1629 | struct kretprobe_trace_entry_head *entry; |
1c024eca | 1630 | struct hlist_head *head; |
e09c8614 | 1631 | int size, __size, dsize; |
4ed7c92d | 1632 | int rctx; |
e08d1c65 | 1633 | |
e87c6bc3 | 1634 | if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs)) |
2541517c AS |
1635 | return; |
1636 | ||
288e984e ON |
1637 | head = this_cpu_ptr(call->perf_events); |
1638 | if (hlist_empty(head)) | |
1639 | return; | |
1640 | ||
c31ffb3f NK |
1641 | dsize = __get_data_size(&tk->tp, regs); |
1642 | __size = sizeof(*entry) + tk->tp.size + dsize; | |
74ebb63e MH |
1643 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1644 | size -= sizeof(u32); | |
444a2a3b | 1645 | |
1e1dcd93 | 1646 | entry = perf_trace_buf_alloc(size, NULL, &rctx); |
430ad5a6 | 1647 | if (!entry) |
1e12a4a7 | 1648 | return; |
e08d1c65 | 1649 | |
c31ffb3f | 1650 | entry->func = (unsigned long)tk->rp.kp.addr; |
a1a138d0 | 1651 | entry->ret_ip = (unsigned long)ri->ret_addr; |
9178412d | 1652 | store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize); |
1e1dcd93 | 1653 | perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, |
8fd0fbbe | 1654 | head, NULL); |
e08d1c65 | 1655 | } |
3da0f180 | 1656 | NOKPROBE_SYMBOL(kretprobe_perf_func); |
41bdc4b4 YS |
1657 | |
1658 | int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type, | |
1659 | const char **symbol, u64 *probe_offset, | |
1660 | u64 *probe_addr, bool perf_type_tracepoint) | |
1661 | { | |
1662 | const char *pevent = trace_event_name(event->tp_event); | |
1663 | const char *group = event->tp_event->class->system; | |
1664 | struct trace_kprobe *tk; | |
1665 | ||
1666 | if (perf_type_tracepoint) | |
1667 | tk = find_trace_kprobe(pevent, group); | |
1668 | else | |
22d5bd68 | 1669 | tk = trace_kprobe_primary_from_call(event->tp_event); |
41bdc4b4 YS |
1670 | if (!tk) |
1671 | return -EINVAL; | |
1672 | ||
1673 | *fd_type = trace_kprobe_is_return(tk) ? BPF_FD_TYPE_KRETPROBE | |
1674 | : BPF_FD_TYPE_KPROBE; | |
1675 | if (tk->symbol) { | |
1676 | *symbol = tk->symbol; | |
1677 | *probe_offset = tk->rp.kp.offset; | |
1678 | *probe_addr = 0; | |
1679 | } else { | |
1680 | *symbol = NULL; | |
1681 | *probe_offset = 0; | |
1682 | *probe_addr = (unsigned long)tk->rp.kp.addr; | |
1683 | } | |
1684 | return 0; | |
1685 | } | |
07b139c8 | 1686 | #endif /* CONFIG_PERF_EVENTS */ |
50d78056 | 1687 | |
3fe3d619 ON |
1688 | /* |
1689 | * called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex. | |
1690 | * | |
1691 | * kprobe_trace_self_tests_init() does enable_trace_probe/disable_trace_probe | |
1692 | * lockless, but we can't race with this __init function. | |
1693 | */ | |
2425bcb9 | 1694 | static int kprobe_register(struct trace_event_call *event, |
fbc1963d | 1695 | enum trace_reg type, void *data) |
2239291a | 1696 | { |
7f1d2f82 | 1697 | struct trace_event_file *file = data; |
1538f888 | 1698 | |
2239291a SR |
1699 | switch (type) { |
1700 | case TRACE_REG_REGISTER: | |
60d53e2c | 1701 | return enable_trace_kprobe(event, file); |
2239291a | 1702 | case TRACE_REG_UNREGISTER: |
60d53e2c | 1703 | return disable_trace_kprobe(event, file); |
2239291a SR |
1704 | |
1705 | #ifdef CONFIG_PERF_EVENTS | |
1706 | case TRACE_REG_PERF_REGISTER: | |
60d53e2c | 1707 | return enable_trace_kprobe(event, NULL); |
2239291a | 1708 | case TRACE_REG_PERF_UNREGISTER: |
60d53e2c | 1709 | return disable_trace_kprobe(event, NULL); |
ceec0b6f JO |
1710 | case TRACE_REG_PERF_OPEN: |
1711 | case TRACE_REG_PERF_CLOSE: | |
489c75c3 JO |
1712 | case TRACE_REG_PERF_ADD: |
1713 | case TRACE_REG_PERF_DEL: | |
ceec0b6f | 1714 | return 0; |
2239291a SR |
1715 | #endif |
1716 | } | |
1717 | return 0; | |
1718 | } | |
50d78056 | 1719 | |
3da0f180 | 1720 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) |
50d78056 | 1721 | { |
c31ffb3f | 1722 | struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp); |
9802d865 | 1723 | int ret = 0; |
e08d1c65 | 1724 | |
a7636d9e | 1725 | raw_cpu_inc(*tk->nhit); |
48182bd2 | 1726 | |
747774d6 | 1727 | if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE)) |
c31ffb3f | 1728 | kprobe_trace_func(tk, regs); |
07b139c8 | 1729 | #ifdef CONFIG_PERF_EVENTS |
747774d6 | 1730 | if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE)) |
9802d865 | 1731 | ret = kprobe_perf_func(tk, regs); |
07b139c8 | 1732 | #endif |
9802d865 | 1733 | return ret; |
50d78056 | 1734 | } |
3da0f180 | 1735 | NOKPROBE_SYMBOL(kprobe_dispatcher); |
50d78056 | 1736 | |
3da0f180 MH |
1737 | static int |
1738 | kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) | |
50d78056 | 1739 | { |
d741bf41 PZ |
1740 | struct kretprobe *rp = get_kretprobe(ri); |
1741 | struct trace_kprobe *tk = container_of(rp, struct trace_kprobe, rp); | |
50d78056 | 1742 | |
a7636d9e | 1743 | raw_cpu_inc(*tk->nhit); |
48182bd2 | 1744 | |
747774d6 | 1745 | if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE)) |
c31ffb3f | 1746 | kretprobe_trace_func(tk, ri, regs); |
07b139c8 | 1747 | #ifdef CONFIG_PERF_EVENTS |
747774d6 | 1748 | if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE)) |
c31ffb3f | 1749 | kretprobe_perf_func(tk, ri, regs); |
07b139c8 | 1750 | #endif |
f2cc020d | 1751 | return 0; /* We don't tweak kernel, so just return 0 */ |
50d78056 | 1752 | } |
3da0f180 | 1753 | NOKPROBE_SYMBOL(kretprobe_dispatcher); |
e08d1c65 | 1754 | |
a9a57763 SR |
1755 | static struct trace_event_functions kretprobe_funcs = { |
1756 | .trace = print_kretprobe_event | |
1757 | }; | |
1758 | ||
1759 | static struct trace_event_functions kprobe_funcs = { | |
1760 | .trace = print_kprobe_event | |
1761 | }; | |
1762 | ||
04ae87a5 PZ |
1763 | static struct trace_event_fields kretprobe_fields_array[] = { |
1764 | { .type = TRACE_FUNCTION_TYPE, | |
1765 | .define_fields = kretprobe_event_define_fields }, | |
1766 | {} | |
1767 | }; | |
1768 | ||
1769 | static struct trace_event_fields kprobe_fields_array[] = { | |
1770 | { .type = TRACE_FUNCTION_TYPE, | |
1771 | .define_fields = kprobe_event_define_fields }, | |
1772 | {} | |
1773 | }; | |
1774 | ||
e3dc9f89 | 1775 | static inline void init_trace_event_call(struct trace_kprobe *tk) |
413d37d1 | 1776 | { |
e3dc9f89 MH |
1777 | struct trace_event_call *call = trace_probe_event_call(&tk->tp); |
1778 | ||
c31ffb3f | 1779 | if (trace_kprobe_is_return(tk)) { |
80decc70 | 1780 | call->event.funcs = &kretprobe_funcs; |
04ae87a5 | 1781 | call->class->fields_array = kretprobe_fields_array; |
413d37d1 | 1782 | } else { |
80decc70 | 1783 | call->event.funcs = &kprobe_funcs; |
04ae87a5 | 1784 | call->class->fields_array = kprobe_fields_array; |
413d37d1 | 1785 | } |
e12f03d7 SL |
1786 | |
1787 | call->flags = TRACE_EVENT_FL_KPROBE; | |
1788 | call->class->reg = kprobe_register; | |
e12f03d7 SL |
1789 | } |
1790 | ||
1791 | static int register_kprobe_event(struct trace_kprobe *tk) | |
1792 | { | |
e3dc9f89 | 1793 | init_trace_event_call(tk); |
f730e0f2 | 1794 | |
46e5376d | 1795 | return trace_probe_register_event_call(&tk->tp); |
413d37d1 MH |
1796 | } |
1797 | ||
c31ffb3f | 1798 | static int unregister_kprobe_event(struct trace_kprobe *tk) |
413d37d1 | 1799 | { |
46e5376d | 1800 | return trace_probe_unregister_event_call(&tk->tp); |
413d37d1 MH |
1801 | } |
1802 | ||
e12f03d7 SL |
1803 | #ifdef CONFIG_PERF_EVENTS |
1804 | /* create a trace_kprobe, but don't add it to global lists */ | |
1805 | struct trace_event_call * | |
1806 | create_local_trace_kprobe(char *func, void *addr, unsigned long offs, | |
1807 | bool is_return) | |
1808 | { | |
1809 | struct trace_kprobe *tk; | |
1810 | int ret; | |
1811 | char *event; | |
1812 | ||
1813 | /* | |
6212dd29 | 1814 | * local trace_kprobes are not added to dyn_event, so they are never |
e12f03d7 SL |
1815 | * searched in find_trace_kprobe(). Therefore, there is no concern of |
1816 | * duplicated name here. | |
1817 | */ | |
1818 | event = func ? func : "DUMMY_EVENT"; | |
1819 | ||
1820 | tk = alloc_trace_kprobe(KPROBE_EVENT_SYSTEM, event, (void *)addr, func, | |
1821 | offs, 0 /* maxactive */, 0 /* nargs */, | |
1822 | is_return); | |
1823 | ||
1824 | if (IS_ERR(tk)) { | |
1825 | pr_info("Failed to allocate trace_probe.(%d)\n", | |
1826 | (int)PTR_ERR(tk)); | |
1827 | return ERR_CAST(tk); | |
1828 | } | |
1829 | ||
e3dc9f89 | 1830 | init_trace_event_call(tk); |
e12f03d7 | 1831 | |
0a46c854 | 1832 | if (traceprobe_set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) { |
e12f03d7 SL |
1833 | ret = -ENOMEM; |
1834 | goto error; | |
1835 | } | |
1836 | ||
1837 | ret = __register_trace_kprobe(tk); | |
f730e0f2 | 1838 | if (ret < 0) |
e12f03d7 SL |
1839 | goto error; |
1840 | ||
e3dc9f89 | 1841 | return trace_probe_event_call(&tk->tp); |
e12f03d7 SL |
1842 | error: |
1843 | free_trace_kprobe(tk); | |
1844 | return ERR_PTR(ret); | |
1845 | } | |
1846 | ||
1847 | void destroy_local_trace_kprobe(struct trace_event_call *event_call) | |
1848 | { | |
1849 | struct trace_kprobe *tk; | |
1850 | ||
60d53e2c MH |
1851 | tk = trace_kprobe_primary_from_call(event_call); |
1852 | if (unlikely(!tk)) | |
1853 | return; | |
e12f03d7 SL |
1854 | |
1855 | if (trace_probe_is_enabled(&tk->tp)) { | |
1856 | WARN_ON(1); | |
1857 | return; | |
1858 | } | |
1859 | ||
1860 | __unregister_trace_kprobe(tk); | |
0fc8c358 | 1861 | |
e12f03d7 SL |
1862 | free_trace_kprobe(tk); |
1863 | } | |
1864 | #endif /* CONFIG_PERF_EVENTS */ | |
1865 | ||
970988e1 MH |
1866 | static __init void enable_boot_kprobe_events(void) |
1867 | { | |
1868 | struct trace_array *tr = top_trace_array(); | |
1869 | struct trace_event_file *file; | |
1870 | struct trace_kprobe *tk; | |
1871 | struct dyn_event *pos; | |
1872 | ||
1873 | mutex_lock(&event_mutex); | |
1874 | for_each_trace_kprobe(tk, pos) { | |
1875 | list_for_each_entry(file, &tr->events, list) | |
e3dc9f89 | 1876 | if (file->event_call == trace_probe_event_call(&tk->tp)) |
970988e1 MH |
1877 | trace_event_enable_disable(file, 1, 0); |
1878 | } | |
1879 | mutex_unlock(&event_mutex); | |
1880 | } | |
1881 | ||
1882 | static __init void setup_boot_kprobe_events(void) | |
1883 | { | |
1884 | char *p, *cmd = kprobe_boot_events_buf; | |
1885 | int ret; | |
1886 | ||
1887 | strreplace(kprobe_boot_events_buf, ',', ' '); | |
1888 | ||
1889 | while (cmd && *cmd != '\0') { | |
1890 | p = strchr(cmd, ';'); | |
1891 | if (p) | |
1892 | *p++ = '\0'; | |
1893 | ||
d262271d | 1894 | ret = create_or_delete_trace_kprobe(cmd); |
970988e1 MH |
1895 | if (ret) |
1896 | pr_warn("Failed to add event(%d): %s\n", ret, cmd); | |
1897 | ||
1898 | cmd = p; | |
1899 | } | |
1900 | ||
1901 | enable_boot_kprobe_events(); | |
1902 | } | |
1903 | ||
d8d4c6d0 | 1904 | /* |
ba0fbfbb MH |
1905 | * Register dynevent at core_initcall. This allows kernel to setup kprobe |
1906 | * events in postcore_initcall without tracefs. | |
d8d4c6d0 MH |
1907 | */ |
1908 | static __init int init_kprobe_trace_early(void) | |
413d37d1 | 1909 | { |
6212dd29 MH |
1910 | int ret; |
1911 | ||
1912 | ret = dyn_event_register(&trace_kprobe_ops); | |
1913 | if (ret) | |
1914 | return ret; | |
413d37d1 | 1915 | |
c31ffb3f | 1916 | if (register_module_notifier(&trace_kprobe_module_nb)) |
61424318 MH |
1917 | return -EINVAL; |
1918 | ||
d8d4c6d0 MH |
1919 | return 0; |
1920 | } | |
ba0fbfbb | 1921 | core_initcall(init_kprobe_trace_early); |
d8d4c6d0 MH |
1922 | |
1923 | /* Make a tracefs interface for controlling probe points */ | |
1924 | static __init int init_kprobe_trace(void) | |
1925 | { | |
22c36b18 | 1926 | int ret; |
d8d4c6d0 MH |
1927 | struct dentry *entry; |
1928 | ||
22c36b18 WY |
1929 | ret = tracing_init_dentry(); |
1930 | if (ret) | |
413d37d1 MH |
1931 | return 0; |
1932 | ||
22c36b18 | 1933 | entry = tracefs_create_file("kprobe_events", 0644, NULL, |
413d37d1 MH |
1934 | NULL, &kprobe_events_ops); |
1935 | ||
cd7e7bd5 | 1936 | /* Event list interface */ |
413d37d1 | 1937 | if (!entry) |
a395d6a7 | 1938 | pr_warn("Could not create tracefs 'kprobe_events' entry\n"); |
cd7e7bd5 MH |
1939 | |
1940 | /* Profile interface */ | |
22c36b18 | 1941 | entry = tracefs_create_file("kprobe_profile", 0444, NULL, |
cd7e7bd5 MH |
1942 | NULL, &kprobe_profile_ops); |
1943 | ||
1944 | if (!entry) | |
a395d6a7 | 1945 | pr_warn("Could not create tracefs 'kprobe_profile' entry\n"); |
970988e1 MH |
1946 | |
1947 | setup_boot_kprobe_events(); | |
1948 | ||
413d37d1 MH |
1949 | return 0; |
1950 | } | |
1951 | fs_initcall(init_kprobe_trace); | |
1952 | ||
1953 | ||
1954 | #ifdef CONFIG_FTRACE_STARTUP_TEST | |
26a346f2 | 1955 | static __init struct trace_event_file * |
c31ffb3f | 1956 | find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr) |
41a7dd42 | 1957 | { |
7f1d2f82 | 1958 | struct trace_event_file *file; |
41a7dd42 MH |
1959 | |
1960 | list_for_each_entry(file, &tr->events, list) | |
e3dc9f89 | 1961 | if (file->event_call == trace_probe_event_call(&tk->tp)) |
41a7dd42 MH |
1962 | return file; |
1963 | ||
1964 | return NULL; | |
1965 | } | |
1966 | ||
3fe3d619 | 1967 | /* |
c31ffb3f | 1968 | * Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this |
3fe3d619 ON |
1969 | * stage, we can do this lockless. |
1970 | */ | |
413d37d1 MH |
1971 | static __init int kprobe_trace_self_tests_init(void) |
1972 | { | |
231e36f4 | 1973 | int ret, warn = 0; |
413d37d1 | 1974 | int (*target)(int, int, int, int, int, int); |
c31ffb3f | 1975 | struct trace_kprobe *tk; |
7f1d2f82 | 1976 | struct trace_event_file *file; |
413d37d1 | 1977 | |
748ec3a2 YY |
1978 | if (tracing_is_disabled()) |
1979 | return -ENODEV; | |
1980 | ||
60efe21e | 1981 | if (tracing_selftest_disabled) |
b6399cc7 | 1982 | return 0; |
b6399cc7 | 1983 | |
413d37d1 MH |
1984 | target = kprobe_trace_selftest_target; |
1985 | ||
1986 | pr_info("Testing kprobe tracing: "); | |
1987 | ||
d262271d | 1988 | ret = create_or_delete_trace_kprobe("p:testprobe kprobe_trace_selftest_target $stack $stack0 +0($stack)"); |
231e36f4 | 1989 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1990 | pr_warn("error on probing function entry.\n"); |
231e36f4 MH |
1991 | warn++; |
1992 | } else { | |
1993 | /* Enable trace point */ | |
c31ffb3f NK |
1994 | tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); |
1995 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1996 | pr_warn("error on getting new probe.\n"); |
231e36f4 | 1997 | warn++; |
41a7dd42 | 1998 | } else { |
c31ffb3f | 1999 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
2000 | if (WARN_ON_ONCE(file == NULL)) { |
2001 | pr_warn("error on getting probe file.\n"); | |
2002 | warn++; | |
2003 | } else | |
60d53e2c MH |
2004 | enable_trace_kprobe( |
2005 | trace_probe_event_call(&tk->tp), file); | |
41a7dd42 | 2006 | } |
231e36f4 | 2007 | } |
413d37d1 | 2008 | |
d262271d | 2009 | ret = create_or_delete_trace_kprobe("r:testprobe2 kprobe_trace_selftest_target $retval"); |
231e36f4 | 2010 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 2011 | pr_warn("error on probing function return.\n"); |
231e36f4 MH |
2012 | warn++; |
2013 | } else { | |
2014 | /* Enable trace point */ | |
c31ffb3f NK |
2015 | tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); |
2016 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 2017 | pr_warn("error on getting 2nd new probe.\n"); |
231e36f4 | 2018 | warn++; |
41a7dd42 | 2019 | } else { |
c31ffb3f | 2020 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
2021 | if (WARN_ON_ONCE(file == NULL)) { |
2022 | pr_warn("error on getting probe file.\n"); | |
2023 | warn++; | |
2024 | } else | |
60d53e2c MH |
2025 | enable_trace_kprobe( |
2026 | trace_probe_event_call(&tk->tp), file); | |
41a7dd42 | 2027 | } |
231e36f4 MH |
2028 | } |
2029 | ||
2030 | if (warn) | |
2031 | goto end; | |
413d37d1 MH |
2032 | |
2033 | ret = target(1, 2, 3, 4, 5, 6); | |
2034 | ||
d4d7ccc8 MN |
2035 | /* |
2036 | * Not expecting an error here, the check is only to prevent the | |
2037 | * optimizer from removing the call to target() as otherwise there | |
2038 | * are no side-effects and the call is never performed. | |
2039 | */ | |
2040 | if (ret != 21) | |
2041 | warn++; | |
2042 | ||
02ca1521 | 2043 | /* Disable trace points before removing it */ |
c31ffb3f NK |
2044 | tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); |
2045 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 2046 | pr_warn("error on getting test probe.\n"); |
02ca1521 | 2047 | warn++; |
41a7dd42 | 2048 | } else { |
d4d7ccc8 MN |
2049 | if (trace_kprobe_nhit(tk) != 1) { |
2050 | pr_warn("incorrect number of testprobe hits\n"); | |
2051 | warn++; | |
2052 | } | |
2053 | ||
c31ffb3f | 2054 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
2055 | if (WARN_ON_ONCE(file == NULL)) { |
2056 | pr_warn("error on getting probe file.\n"); | |
2057 | warn++; | |
2058 | } else | |
60d53e2c MH |
2059 | disable_trace_kprobe( |
2060 | trace_probe_event_call(&tk->tp), file); | |
41a7dd42 | 2061 | } |
02ca1521 | 2062 | |
c31ffb3f NK |
2063 | tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); |
2064 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 2065 | pr_warn("error on getting 2nd test probe.\n"); |
02ca1521 | 2066 | warn++; |
41a7dd42 | 2067 | } else { |
d4d7ccc8 MN |
2068 | if (trace_kprobe_nhit(tk) != 1) { |
2069 | pr_warn("incorrect number of testprobe2 hits\n"); | |
2070 | warn++; | |
2071 | } | |
2072 | ||
c31ffb3f | 2073 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
2074 | if (WARN_ON_ONCE(file == NULL)) { |
2075 | pr_warn("error on getting probe file.\n"); | |
2076 | warn++; | |
2077 | } else | |
60d53e2c MH |
2078 | disable_trace_kprobe( |
2079 | trace_probe_event_call(&tk->tp), file); | |
41a7dd42 | 2080 | } |
02ca1521 | 2081 | |
d262271d | 2082 | ret = create_or_delete_trace_kprobe("-:testprobe"); |
231e36f4 | 2083 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 2084 | pr_warn("error on deleting a probe.\n"); |
231e36f4 MH |
2085 | warn++; |
2086 | } | |
2087 | ||
d262271d | 2088 | ret = create_or_delete_trace_kprobe("-:testprobe2"); |
231e36f4 | 2089 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 2090 | pr_warn("error on deleting a probe.\n"); |
231e36f4 MH |
2091 | warn++; |
2092 | } | |
413d37d1 | 2093 | |
231e36f4 | 2094 | end: |
6212dd29 MH |
2095 | ret = dyn_events_release_all(&trace_kprobe_ops); |
2096 | if (WARN_ON_ONCE(ret)) { | |
2097 | pr_warn("error on cleaning up probes.\n"); | |
2098 | warn++; | |
2099 | } | |
30e7d894 TG |
2100 | /* |
2101 | * Wait for the optimizer work to finish. Otherwise it might fiddle | |
2102 | * with probes in already freed __init text. | |
2103 | */ | |
2104 | wait_for_kprobe_optimizer(); | |
231e36f4 MH |
2105 | if (warn) |
2106 | pr_cont("NG: Some tests are failed. Please check them.\n"); | |
2107 | else | |
2108 | pr_cont("OK\n"); | |
413d37d1 MH |
2109 | return 0; |
2110 | } | |
2111 | ||
2112 | late_initcall(kprobe_trace_self_tests_init); | |
2113 | ||
2114 | #endif |