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Commit | Line | Data |
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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; | |
b6399cc7 | 28 | static bool kprobe_boot_events_enabled __initdata; |
970988e1 MH |
29 | |
30 | static int __init set_kprobe_boot_events(char *str) | |
31 | { | |
32 | strlcpy(kprobe_boot_events_buf, str, COMMAND_LINE_SIZE); | |
33 | return 0; | |
34 | } | |
35 | __setup("kprobe_event=", set_kprobe_boot_events); | |
e09c8614 | 36 | |
6212dd29 MH |
37 | static int trace_kprobe_create(int argc, const char **argv); |
38 | static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev); | |
39 | static int trace_kprobe_release(struct dyn_event *ev); | |
40 | static bool trace_kprobe_is_busy(struct dyn_event *ev); | |
41 | static bool trace_kprobe_match(const char *system, const char *event, | |
30199137 | 42 | int argc, const char **argv, struct dyn_event *ev); |
6212dd29 MH |
43 | |
44 | static struct dyn_event_operations trace_kprobe_ops = { | |
45 | .create = trace_kprobe_create, | |
46 | .show = trace_kprobe_show, | |
47 | .is_busy = trace_kprobe_is_busy, | |
48 | .free = trace_kprobe_release, | |
49 | .match = trace_kprobe_match, | |
50 | }; | |
51 | ||
cede666e | 52 | /* |
77b44d1b | 53 | * Kprobe event core functions |
413d37d1 | 54 | */ |
c31ffb3f | 55 | struct trace_kprobe { |
6212dd29 | 56 | struct dyn_event devent; |
4a846b44 | 57 | struct kretprobe rp; /* Use rp.kp for kprobe use */ |
a7636d9e | 58 | unsigned long __percpu *nhit; |
413d37d1 | 59 | const char *symbol; /* symbol name */ |
c31ffb3f | 60 | struct trace_probe tp; |
413d37d1 MH |
61 | }; |
62 | ||
6212dd29 MH |
63 | static bool is_trace_kprobe(struct dyn_event *ev) |
64 | { | |
65 | return ev->ops == &trace_kprobe_ops; | |
66 | } | |
67 | ||
68 | static struct trace_kprobe *to_trace_kprobe(struct dyn_event *ev) | |
69 | { | |
70 | return container_of(ev, struct trace_kprobe, devent); | |
71 | } | |
72 | ||
73 | /** | |
74 | * for_each_trace_kprobe - iterate over the trace_kprobe list | |
75 | * @pos: the struct trace_kprobe * for each entry | |
76 | * @dpos: the struct dyn_event * to use as a loop cursor | |
77 | */ | |
78 | #define for_each_trace_kprobe(pos, dpos) \ | |
79 | for_each_dyn_event(dpos) \ | |
80 | if (is_trace_kprobe(dpos) && (pos = to_trace_kprobe(dpos))) | |
81 | ||
c31ffb3f NK |
82 | #define SIZEOF_TRACE_KPROBE(n) \ |
83 | (offsetof(struct trace_kprobe, tp.args) + \ | |
eca0d916 | 84 | (sizeof(struct probe_arg) * (n))) |
a82378d8 | 85 | |
3da0f180 | 86 | static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk) |
413d37d1 | 87 | { |
c31ffb3f | 88 | return tk->rp.handler != NULL; |
413d37d1 MH |
89 | } |
90 | ||
3da0f180 | 91 | static nokprobe_inline const char *trace_kprobe_symbol(struct trace_kprobe *tk) |
413d37d1 | 92 | { |
c31ffb3f | 93 | return tk->symbol ? tk->symbol : "unknown"; |
413d37d1 MH |
94 | } |
95 | ||
3da0f180 | 96 | static nokprobe_inline unsigned long trace_kprobe_offset(struct trace_kprobe *tk) |
61424318 | 97 | { |
c31ffb3f | 98 | return tk->rp.kp.offset; |
61424318 MH |
99 | } |
100 | ||
3da0f180 | 101 | static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk) |
61424318 | 102 | { |
c31ffb3f | 103 | return !!(kprobe_gone(&tk->rp.kp)); |
61424318 MH |
104 | } |
105 | ||
3da0f180 | 106 | static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, |
c31ffb3f | 107 | struct module *mod) |
61424318 MH |
108 | { |
109 | int len = strlen(mod->name); | |
c31ffb3f | 110 | const char *name = trace_kprobe_symbol(tk); |
61424318 MH |
111 | return strncmp(mod->name, name, len) == 0 && name[len] == ':'; |
112 | } | |
113 | ||
59158ec4 | 114 | static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) |
61424318 | 115 | { |
59158ec4 MH |
116 | char *p; |
117 | bool ret; | |
118 | ||
119 | if (!tk->symbol) | |
120 | return false; | |
121 | p = strchr(tk->symbol, ':'); | |
122 | if (!p) | |
123 | return true; | |
124 | *p = '\0'; | |
125 | mutex_lock(&module_mutex); | |
126 | ret = !!find_module(tk->symbol); | |
127 | mutex_unlock(&module_mutex); | |
128 | *p = ':'; | |
129 | ||
130 | return ret; | |
61424318 MH |
131 | } |
132 | ||
6212dd29 MH |
133 | static bool trace_kprobe_is_busy(struct dyn_event *ev) |
134 | { | |
135 | struct trace_kprobe *tk = to_trace_kprobe(ev); | |
136 | ||
137 | return trace_probe_is_enabled(&tk->tp); | |
138 | } | |
139 | ||
eb5bf813 MH |
140 | static bool trace_kprobe_match_command_head(struct trace_kprobe *tk, |
141 | int argc, const char **argv) | |
142 | { | |
143 | char buf[MAX_ARGSTR_LEN + 1]; | |
144 | ||
145 | if (!argc) | |
146 | return true; | |
147 | ||
148 | if (!tk->symbol) | |
149 | snprintf(buf, sizeof(buf), "0x%p", tk->rp.kp.addr); | |
150 | else if (tk->rp.kp.offset) | |
151 | snprintf(buf, sizeof(buf), "%s+%u", | |
152 | trace_kprobe_symbol(tk), tk->rp.kp.offset); | |
153 | else | |
154 | snprintf(buf, sizeof(buf), "%s", trace_kprobe_symbol(tk)); | |
155 | if (strcmp(buf, argv[0])) | |
156 | return false; | |
157 | argc--; argv++; | |
158 | ||
159 | return trace_probe_match_command_args(&tk->tp, argc, argv); | |
160 | } | |
161 | ||
6212dd29 | 162 | static bool trace_kprobe_match(const char *system, const char *event, |
30199137 | 163 | int argc, const char **argv, struct dyn_event *ev) |
6212dd29 MH |
164 | { |
165 | struct trace_kprobe *tk = to_trace_kprobe(ev); | |
166 | ||
b55ce203 | 167 | return strcmp(trace_probe_name(&tk->tp), event) == 0 && |
eb5bf813 MH |
168 | (!system || strcmp(trace_probe_group_name(&tk->tp), system) == 0) && |
169 | trace_kprobe_match_command_head(tk, argc, argv); | |
6212dd29 MH |
170 | } |
171 | ||
f18f97ac MN |
172 | static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk) |
173 | { | |
174 | unsigned long nhit = 0; | |
175 | int cpu; | |
176 | ||
177 | for_each_possible_cpu(cpu) | |
178 | nhit += *per_cpu_ptr(tk->nhit, cpu); | |
179 | ||
180 | return nhit; | |
181 | } | |
182 | ||
715fa2fd MH |
183 | static nokprobe_inline bool trace_kprobe_is_registered(struct trace_kprobe *tk) |
184 | { | |
185 | return !(list_empty(&tk->rp.kp.list) && | |
186 | hlist_unhashed(&tk->rp.kp.hlist)); | |
187 | } | |
188 | ||
6bc6c77c | 189 | /* Return 0 if it fails to find the symbol address */ |
45408c4f MH |
190 | static nokprobe_inline |
191 | unsigned long trace_kprobe_address(struct trace_kprobe *tk) | |
192 | { | |
193 | unsigned long addr; | |
194 | ||
195 | if (tk->symbol) { | |
196 | addr = (unsigned long) | |
197 | kallsyms_lookup_name(trace_kprobe_symbol(tk)); | |
6bc6c77c MH |
198 | if (addr) |
199 | addr += tk->rp.kp.offset; | |
45408c4f MH |
200 | } else { |
201 | addr = (unsigned long)tk->rp.kp.addr; | |
202 | } | |
203 | return addr; | |
204 | } | |
205 | ||
60d53e2c MH |
206 | static nokprobe_inline struct trace_kprobe * |
207 | trace_kprobe_primary_from_call(struct trace_event_call *call) | |
208 | { | |
209 | struct trace_probe *tp; | |
210 | ||
211 | tp = trace_probe_primary_from_call(call); | |
212 | if (WARN_ON_ONCE(!tp)) | |
213 | return NULL; | |
214 | ||
215 | return container_of(tp, struct trace_kprobe, tp); | |
216 | } | |
217 | ||
b4da3340 | 218 | bool trace_kprobe_on_func_entry(struct trace_event_call *call) |
9802d865 | 219 | { |
60d53e2c | 220 | struct trace_kprobe *tk = trace_kprobe_primary_from_call(call); |
b4da3340 | 221 | |
60d53e2c | 222 | return tk ? kprobe_on_func_entry(tk->rp.kp.addr, |
b4da3340 | 223 | tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name, |
60d53e2c | 224 | tk->rp.kp.addr ? 0 : tk->rp.kp.offset) : false; |
9802d865 JB |
225 | } |
226 | ||
b4da3340 | 227 | bool trace_kprobe_error_injectable(struct trace_event_call *call) |
9802d865 | 228 | { |
60d53e2c | 229 | struct trace_kprobe *tk = trace_kprobe_primary_from_call(call); |
9802d865 | 230 | |
60d53e2c MH |
231 | return tk ? within_error_injection_list(trace_kprobe_address(tk)) : |
232 | false; | |
9802d865 JB |
233 | } |
234 | ||
c31ffb3f NK |
235 | static int register_kprobe_event(struct trace_kprobe *tk); |
236 | static int unregister_kprobe_event(struct trace_kprobe *tk); | |
413d37d1 | 237 | |
50d78056 MH |
238 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); |
239 | static int kretprobe_dispatcher(struct kretprobe_instance *ri, | |
240 | struct pt_regs *regs); | |
241 | ||
455b2899 MH |
242 | static void free_trace_kprobe(struct trace_kprobe *tk) |
243 | { | |
244 | if (tk) { | |
245 | trace_probe_cleanup(&tk->tp); | |
246 | kfree(tk->symbol); | |
247 | free_percpu(tk->nhit); | |
248 | kfree(tk); | |
249 | } | |
250 | } | |
251 | ||
4a846b44 MH |
252 | /* |
253 | * Allocate new trace_probe and initialize it (including kprobes). | |
254 | */ | |
c31ffb3f | 255 | static struct trace_kprobe *alloc_trace_kprobe(const char *group, |
f52487e9 | 256 | const char *event, |
4a846b44 MH |
257 | void *addr, |
258 | const char *symbol, | |
259 | unsigned long offs, | |
696ced4f | 260 | int maxactive, |
3a6b7666 | 261 | int nargs, bool is_return) |
413d37d1 | 262 | { |
c31ffb3f | 263 | struct trace_kprobe *tk; |
6f3cf440 | 264 | int ret = -ENOMEM; |
413d37d1 | 265 | |
c31ffb3f NK |
266 | tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL); |
267 | if (!tk) | |
6f3cf440 | 268 | return ERR_PTR(ret); |
413d37d1 | 269 | |
a7636d9e MKL |
270 | tk->nhit = alloc_percpu(unsigned long); |
271 | if (!tk->nhit) | |
272 | goto error; | |
273 | ||
413d37d1 | 274 | if (symbol) { |
c31ffb3f NK |
275 | tk->symbol = kstrdup(symbol, GFP_KERNEL); |
276 | if (!tk->symbol) | |
413d37d1 | 277 | goto error; |
c31ffb3f NK |
278 | tk->rp.kp.symbol_name = tk->symbol; |
279 | tk->rp.kp.offset = offs; | |
4a846b44 | 280 | } else |
c31ffb3f | 281 | tk->rp.kp.addr = addr; |
4a846b44 MH |
282 | |
283 | if (is_return) | |
c31ffb3f | 284 | tk->rp.handler = kretprobe_dispatcher; |
4a846b44 | 285 | else |
c31ffb3f | 286 | tk->rp.kp.pre_handler = kprobe_dispatcher; |
4a846b44 | 287 | |
696ced4f | 288 | tk->rp.maxactive = maxactive; |
715fa2fd MH |
289 | INIT_HLIST_NODE(&tk->rp.kp.hlist); |
290 | INIT_LIST_HEAD(&tk->rp.kp.list); | |
696ced4f | 291 | |
b61387cb | 292 | ret = trace_probe_init(&tk->tp, event, group, false); |
455b2899 | 293 | if (ret < 0) |
f52487e9 MH |
294 | goto error; |
295 | ||
6212dd29 | 296 | dyn_event_init(&tk->devent, &trace_kprobe_ops); |
c31ffb3f | 297 | return tk; |
413d37d1 | 298 | error: |
455b2899 | 299 | free_trace_kprobe(tk); |
6f3cf440 | 300 | return ERR_PTR(ret); |
413d37d1 MH |
301 | } |
302 | ||
c31ffb3f NK |
303 | static struct trace_kprobe *find_trace_kprobe(const char *event, |
304 | const char *group) | |
413d37d1 | 305 | { |
6212dd29 | 306 | struct dyn_event *pos; |
c31ffb3f | 307 | struct trace_kprobe *tk; |
413d37d1 | 308 | |
6212dd29 | 309 | for_each_trace_kprobe(tk, pos) |
b55ce203 MH |
310 | if (strcmp(trace_probe_name(&tk->tp), event) == 0 && |
311 | strcmp(trace_probe_group_name(&tk->tp), group) == 0) | |
c31ffb3f | 312 | return tk; |
413d37d1 MH |
313 | return NULL; |
314 | } | |
315 | ||
87107a25 SRV |
316 | static inline int __enable_trace_kprobe(struct trace_kprobe *tk) |
317 | { | |
318 | int ret = 0; | |
319 | ||
715fa2fd | 320 | if (trace_kprobe_is_registered(tk) && !trace_kprobe_has_gone(tk)) { |
87107a25 SRV |
321 | if (trace_kprobe_is_return(tk)) |
322 | ret = enable_kretprobe(&tk->rp); | |
323 | else | |
324 | ret = enable_kprobe(&tk->rp.kp); | |
325 | } | |
326 | ||
327 | return ret; | |
328 | } | |
329 | ||
60d53e2c MH |
330 | static void __disable_trace_kprobe(struct trace_probe *tp) |
331 | { | |
332 | struct trace_probe *pos; | |
333 | struct trace_kprobe *tk; | |
334 | ||
335 | list_for_each_entry(pos, trace_probe_probe_list(tp), list) { | |
336 | tk = container_of(pos, struct trace_kprobe, tp); | |
337 | if (!trace_kprobe_is_registered(tk)) | |
338 | continue; | |
339 | if (trace_kprobe_is_return(tk)) | |
340 | disable_kretprobe(&tk->rp); | |
341 | else | |
342 | disable_kprobe(&tk->rp.kp); | |
343 | } | |
344 | } | |
345 | ||
41a7dd42 MH |
346 | /* |
347 | * Enable trace_probe | |
348 | * if the file is NULL, enable "perf" handler, or enable "trace" handler. | |
349 | */ | |
60d53e2c MH |
350 | static int enable_trace_kprobe(struct trace_event_call *call, |
351 | struct trace_event_file *file) | |
1538f888 | 352 | { |
60d53e2c MH |
353 | struct trace_probe *pos, *tp; |
354 | struct trace_kprobe *tk; | |
355 | bool enabled; | |
1538f888 MH |
356 | int ret = 0; |
357 | ||
60d53e2c MH |
358 | tp = trace_probe_primary_from_call(call); |
359 | if (WARN_ON_ONCE(!tp)) | |
360 | return -ENODEV; | |
361 | enabled = trace_probe_is_enabled(tp); | |
362 | ||
363 | /* This also changes "enabled" state */ | |
41a7dd42 | 364 | if (file) { |
60d53e2c | 365 | ret = trace_probe_add_file(tp, file); |
b5f935ee MH |
366 | if (ret) |
367 | return ret; | |
368 | } else | |
60d53e2c | 369 | trace_probe_set_flag(tp, TP_FLAG_PROFILE); |
41a7dd42 | 370 | |
b5f935ee MH |
371 | if (enabled) |
372 | return 0; | |
87107a25 | 373 | |
60d53e2c MH |
374 | list_for_each_entry(pos, trace_probe_probe_list(tp), list) { |
375 | tk = container_of(pos, struct trace_kprobe, tp); | |
376 | if (trace_kprobe_has_gone(tk)) | |
377 | continue; | |
378 | ret = __enable_trace_kprobe(tk); | |
44d00dc7 | 379 | if (ret) |
60d53e2c | 380 | break; |
60d53e2c MH |
381 | enabled = true; |
382 | } | |
383 | ||
44d00dc7 MH |
384 | if (ret) { |
385 | /* Failed to enable one of them. Roll back all */ | |
386 | if (enabled) | |
387 | __disable_trace_kprobe(tp); | |
b5f935ee | 388 | if (file) |
60d53e2c | 389 | trace_probe_remove_file(tp, file); |
b5f935ee | 390 | else |
60d53e2c | 391 | trace_probe_clear_flag(tp, TP_FLAG_PROFILE); |
57ea2a34 | 392 | } |
b5f935ee | 393 | |
1538f888 MH |
394 | return ret; |
395 | } | |
396 | ||
41a7dd42 MH |
397 | /* |
398 | * Disable trace_probe | |
399 | * if the file is NULL, disable "perf" handler, or disable "trace" handler. | |
400 | */ | |
60d53e2c MH |
401 | static int disable_trace_kprobe(struct trace_event_call *call, |
402 | struct trace_event_file *file) | |
1538f888 | 403 | { |
60d53e2c MH |
404 | struct trace_probe *tp; |
405 | ||
406 | tp = trace_probe_primary_from_call(call); | |
407 | if (WARN_ON_ONCE(!tp)) | |
408 | return -ENODEV; | |
41a7dd42 | 409 | |
41a7dd42 | 410 | if (file) { |
b5f935ee MH |
411 | if (!trace_probe_get_file_link(tp, file)) |
412 | return -ENOENT; | |
413 | if (!trace_probe_has_single_file(tp)) | |
b04d52e3 | 414 | goto out; |
747774d6 | 415 | trace_probe_clear_flag(tp, TP_FLAG_TRACE); |
41a7dd42 | 416 | } else |
747774d6 | 417 | trace_probe_clear_flag(tp, TP_FLAG_PROFILE); |
41a7dd42 | 418 | |
60d53e2c MH |
419 | if (!trace_probe_is_enabled(tp)) |
420 | __disable_trace_kprobe(tp); | |
e12f03d7 | 421 | |
3fe3d619 | 422 | out: |
b5f935ee | 423 | if (file) |
a232e270 | 424 | /* |
b5f935ee MH |
425 | * Synchronization is done in below function. For perf event, |
426 | * file == NULL and perf_trace_event_unreg() calls | |
427 | * tracepoint_synchronize_unregister() to ensure synchronize | |
428 | * event. We don't need to care about it. | |
a232e270 | 429 | */ |
b5f935ee | 430 | trace_probe_remove_file(tp, file); |
a232e270 | 431 | |
60d53e2c | 432 | return 0; |
1538f888 MH |
433 | } |
434 | ||
45408c4f MH |
435 | #if defined(CONFIG_KPROBES_ON_FTRACE) && \ |
436 | !defined(CONFIG_KPROBE_EVENTS_ON_NOTRACE) | |
c7411a1a | 437 | static bool __within_notrace_func(unsigned long addr) |
45408c4f | 438 | { |
c7411a1a | 439 | unsigned long offset, size; |
45408c4f | 440 | |
6bc6c77c MH |
441 | if (!addr || !kallsyms_lookup_size_offset(addr, &size, &offset)) |
442 | return false; | |
45408c4f | 443 | |
9161a864 MH |
444 | /* Get the entry address of the target function */ |
445 | addr -= offset; | |
446 | ||
447 | /* | |
448 | * Since ftrace_location_range() does inclusive range check, we need | |
449 | * to subtract 1 byte from the end address. | |
450 | */ | |
451 | return !ftrace_location_range(addr, addr + size - 1); | |
45408c4f | 452 | } |
c7411a1a MH |
453 | |
454 | static bool within_notrace_func(struct trace_kprobe *tk) | |
455 | { | |
dcbd21c9 | 456 | unsigned long addr = trace_kprobe_address(tk); |
c7411a1a MH |
457 | char symname[KSYM_NAME_LEN], *p; |
458 | ||
459 | if (!__within_notrace_func(addr)) | |
460 | return false; | |
461 | ||
462 | /* Check if the address is on a suffixed-symbol */ | |
463 | if (!lookup_symbol_name(addr, symname)) { | |
464 | p = strchr(symname, '.'); | |
465 | if (!p) | |
466 | return true; | |
467 | *p = '\0'; | |
468 | addr = (unsigned long)kprobe_lookup_name(symname, 0); | |
469 | if (addr) | |
470 | return __within_notrace_func(addr); | |
471 | } | |
472 | ||
473 | return true; | |
474 | } | |
45408c4f MH |
475 | #else |
476 | #define within_notrace_func(tk) (false) | |
477 | #endif | |
478 | ||
61424318 | 479 | /* Internal register function - just handle k*probes and flags */ |
c31ffb3f | 480 | static int __register_trace_kprobe(struct trace_kprobe *tk) |
413d37d1 | 481 | { |
a6682814 | 482 | int i, ret; |
61424318 | 483 | |
a94549dd DH |
484 | ret = security_locked_down(LOCKDOWN_KPROBES); |
485 | if (ret) | |
486 | return ret; | |
487 | ||
715fa2fd | 488 | if (trace_kprobe_is_registered(tk)) |
61424318 MH |
489 | return -EINVAL; |
490 | ||
45408c4f MH |
491 | if (within_notrace_func(tk)) { |
492 | pr_warn("Could not probe notrace function %s\n", | |
493 | trace_kprobe_symbol(tk)); | |
494 | return -EINVAL; | |
495 | } | |
496 | ||
a6682814 MH |
497 | for (i = 0; i < tk->tp.nr_args; i++) { |
498 | ret = traceprobe_update_arg(&tk->tp.args[i]); | |
499 | if (ret) | |
500 | return ret; | |
501 | } | |
502 | ||
61424318 | 503 | /* Set/clear disabled flag according to tp->flag */ |
c31ffb3f NK |
504 | if (trace_probe_is_enabled(&tk->tp)) |
505 | tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; | |
61424318 | 506 | else |
c31ffb3f | 507 | tk->rp.kp.flags |= KPROBE_FLAG_DISABLED; |
61424318 | 508 | |
c31ffb3f NK |
509 | if (trace_kprobe_is_return(tk)) |
510 | ret = register_kretprobe(&tk->rp); | |
413d37d1 | 511 | else |
c31ffb3f | 512 | ret = register_kprobe(&tk->rp.kp); |
61424318 | 513 | |
61424318 MH |
514 | return ret; |
515 | } | |
516 | ||
517 | /* Internal unregister function - just handle k*probes and flags */ | |
c31ffb3f | 518 | static void __unregister_trace_kprobe(struct trace_kprobe *tk) |
61424318 | 519 | { |
715fa2fd | 520 | if (trace_kprobe_is_registered(tk)) { |
c31ffb3f NK |
521 | if (trace_kprobe_is_return(tk)) |
522 | unregister_kretprobe(&tk->rp); | |
61424318 | 523 | else |
c31ffb3f | 524 | unregister_kprobe(&tk->rp.kp); |
715fa2fd MH |
525 | /* Cleanup kprobe for reuse and mark it unregistered */ |
526 | INIT_HLIST_NODE(&tk->rp.kp.hlist); | |
527 | INIT_LIST_HEAD(&tk->rp.kp.list); | |
c31ffb3f NK |
528 | if (tk->rp.kp.symbol_name) |
529 | tk->rp.kp.addr = NULL; | |
61424318 MH |
530 | } |
531 | } | |
532 | ||
6212dd29 | 533 | /* Unregister a trace_probe and probe_event */ |
c31ffb3f | 534 | static int unregister_trace_kprobe(struct trace_kprobe *tk) |
61424318 | 535 | { |
ca89bc07 MH |
536 | /* If other probes are on the event, just unregister kprobe */ |
537 | if (trace_probe_has_sibling(&tk->tp)) | |
538 | goto unreg; | |
539 | ||
02ca1521 | 540 | /* Enabled event can not be unregistered */ |
c31ffb3f | 541 | if (trace_probe_is_enabled(&tk->tp)) |
02ca1521 MH |
542 | return -EBUSY; |
543 | ||
40c32592 | 544 | /* Will fail if probe is being used by ftrace or perf */ |
c31ffb3f | 545 | if (unregister_kprobe_event(tk)) |
40c32592 SRRH |
546 | return -EBUSY; |
547 | ||
ca89bc07 | 548 | unreg: |
c31ffb3f | 549 | __unregister_trace_kprobe(tk); |
6212dd29 | 550 | dyn_event_remove(&tk->devent); |
ca89bc07 | 551 | trace_probe_unlink(&tk->tp); |
02ca1521 MH |
552 | |
553 | return 0; | |
413d37d1 MH |
554 | } |
555 | ||
fe60b0ce MH |
556 | static bool trace_kprobe_has_same_kprobe(struct trace_kprobe *orig, |
557 | struct trace_kprobe *comp) | |
558 | { | |
559 | struct trace_probe_event *tpe = orig->tp.event; | |
560 | struct trace_probe *pos; | |
561 | int i; | |
562 | ||
563 | list_for_each_entry(pos, &tpe->probes, list) { | |
564 | orig = container_of(pos, struct trace_kprobe, tp); | |
565 | if (strcmp(trace_kprobe_symbol(orig), | |
566 | trace_kprobe_symbol(comp)) || | |
567 | trace_kprobe_offset(orig) != trace_kprobe_offset(comp)) | |
568 | continue; | |
569 | ||
570 | /* | |
571 | * trace_probe_compare_arg_type() ensured that nr_args and | |
572 | * each argument name and type are same. Let's compare comm. | |
573 | */ | |
574 | for (i = 0; i < orig->tp.nr_args; i++) { | |
575 | if (strcmp(orig->tp.args[i].comm, | |
576 | comp->tp.args[i].comm)) | |
f8d7ab2b | 577 | break; |
fe60b0ce MH |
578 | } |
579 | ||
f8d7ab2b SD |
580 | if (i == orig->tp.nr_args) |
581 | return true; | |
fe60b0ce MH |
582 | } |
583 | ||
584 | return false; | |
585 | } | |
586 | ||
ca89bc07 MH |
587 | static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to) |
588 | { | |
589 | int ret; | |
590 | ||
fe60b0ce MH |
591 | ret = trace_probe_compare_arg_type(&tk->tp, &to->tp); |
592 | if (ret) { | |
593 | /* Note that argument starts index = 2 */ | |
594 | trace_probe_log_set_index(ret + 1); | |
595 | trace_probe_log_err(0, DIFF_ARG_TYPE); | |
596 | return -EEXIST; | |
597 | } | |
598 | if (trace_kprobe_has_same_kprobe(to, tk)) { | |
599 | trace_probe_log_set_index(0); | |
600 | trace_probe_log_err(0, SAME_PROBE); | |
601 | return -EEXIST; | |
602 | } | |
603 | ||
ca89bc07 MH |
604 | /* Append to existing event */ |
605 | ret = trace_probe_append(&tk->tp, &to->tp); | |
606 | if (ret) | |
607 | return ret; | |
608 | ||
609 | /* Register k*probe */ | |
610 | ret = __register_trace_kprobe(tk); | |
611 | if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) { | |
612 | pr_warn("This probe might be able to register after target module is loaded. Continue.\n"); | |
613 | ret = 0; | |
614 | } | |
615 | ||
616 | if (ret) | |
617 | trace_probe_unlink(&tk->tp); | |
618 | else | |
619 | dyn_event_add(&tk->devent); | |
620 | ||
621 | return ret; | |
622 | } | |
623 | ||
413d37d1 | 624 | /* Register a trace_probe and probe_event */ |
c31ffb3f | 625 | static int register_trace_kprobe(struct trace_kprobe *tk) |
413d37d1 | 626 | { |
c31ffb3f | 627 | struct trace_kprobe *old_tk; |
413d37d1 MH |
628 | int ret; |
629 | ||
6212dd29 | 630 | mutex_lock(&event_mutex); |
413d37d1 | 631 | |
b55ce203 MH |
632 | old_tk = find_trace_kprobe(trace_probe_name(&tk->tp), |
633 | trace_probe_group_name(&tk->tp)); | |
c31ffb3f | 634 | if (old_tk) { |
ca89bc07 MH |
635 | if (trace_kprobe_is_return(tk) != trace_kprobe_is_return(old_tk)) { |
636 | trace_probe_log_set_index(0); | |
637 | trace_probe_log_err(0, DIFF_PROBE_TYPE); | |
638 | ret = -EEXIST; | |
639 | } else { | |
fe60b0ce | 640 | ret = append_trace_kprobe(tk, old_tk); |
ca89bc07 MH |
641 | } |
642 | goto end; | |
2d5e067e | 643 | } |
61424318 MH |
644 | |
645 | /* Register new event */ | |
c31ffb3f | 646 | ret = register_kprobe_event(tk); |
2d5e067e | 647 | if (ret) { |
a395d6a7 | 648 | pr_warn("Failed to register probe event(%d)\n", ret); |
2d5e067e MH |
649 | goto end; |
650 | } | |
651 | ||
61424318 | 652 | /* Register k*probe */ |
c31ffb3f | 653 | ret = __register_trace_kprobe(tk); |
59158ec4 MH |
654 | if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) { |
655 | pr_warn("This probe might be able to register after target module is loaded. Continue.\n"); | |
656 | ret = 0; | |
657 | } | |
658 | ||
61424318 | 659 | if (ret < 0) |
c31ffb3f | 660 | unregister_kprobe_event(tk); |
61424318 | 661 | else |
6212dd29 | 662 | dyn_event_add(&tk->devent); |
61424318 | 663 | |
413d37d1 | 664 | end: |
6212dd29 | 665 | mutex_unlock(&event_mutex); |
413d37d1 MH |
666 | return ret; |
667 | } | |
668 | ||
61424318 | 669 | /* Module notifier call back, checking event on the module */ |
c31ffb3f | 670 | static int trace_kprobe_module_callback(struct notifier_block *nb, |
61424318 MH |
671 | unsigned long val, void *data) |
672 | { | |
673 | struct module *mod = data; | |
6212dd29 | 674 | struct dyn_event *pos; |
c31ffb3f | 675 | struct trace_kprobe *tk; |
61424318 MH |
676 | int ret; |
677 | ||
678 | if (val != MODULE_STATE_COMING) | |
679 | return NOTIFY_DONE; | |
680 | ||
681 | /* Update probes on coming module */ | |
6212dd29 MH |
682 | mutex_lock(&event_mutex); |
683 | for_each_trace_kprobe(tk, pos) { | |
c31ffb3f | 684 | if (trace_kprobe_within_module(tk, mod)) { |
02ca1521 | 685 | /* Don't need to check busy - this should have gone. */ |
c31ffb3f NK |
686 | __unregister_trace_kprobe(tk); |
687 | ret = __register_trace_kprobe(tk); | |
61424318 | 688 | if (ret) |
a395d6a7 | 689 | pr_warn("Failed to re-register probe %s on %s: %d\n", |
b55ce203 | 690 | trace_probe_name(&tk->tp), |
a395d6a7 | 691 | mod->name, ret); |
61424318 MH |
692 | } |
693 | } | |
6212dd29 | 694 | mutex_unlock(&event_mutex); |
61424318 MH |
695 | |
696 | return NOTIFY_DONE; | |
697 | } | |
698 | ||
c31ffb3f NK |
699 | static struct notifier_block trace_kprobe_module_nb = { |
700 | .notifier_call = trace_kprobe_module_callback, | |
61424318 MH |
701 | .priority = 1 /* Invoked after kprobe module callback */ |
702 | }; | |
703 | ||
fca18a47 NR |
704 | /* Convert certain expected symbols into '_' when generating event names */ |
705 | static inline void sanitize_event_name(char *name) | |
706 | { | |
707 | while (*name++ != '\0') | |
708 | if (*name == ':' || *name == '.') | |
709 | *name = '_'; | |
710 | } | |
711 | ||
6212dd29 | 712 | static int trace_kprobe_create(int argc, const char *argv[]) |
413d37d1 MH |
713 | { |
714 | /* | |
715 | * Argument syntax: | |
696ced4f AC |
716 | * - Add kprobe: |
717 | * p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS] | |
718 | * - Add kretprobe: | |
719 | * r[MAXACTIVE][:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS] | |
413d37d1 | 720 | * Fetch args: |
2e06ff63 MH |
721 | * $retval : fetch return value |
722 | * $stack : fetch stack address | |
723 | * $stackN : fetch Nth of stack (N:0-) | |
35abb67d | 724 | * $comm : fetch current task comm |
413d37d1 MH |
725 | * @ADDR : fetch memory at ADDR (ADDR should be in kernel) |
726 | * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) | |
727 | * %REG : fetch register REG | |
93ccae7a | 728 | * Dereferencing memory fetch: |
413d37d1 | 729 | * +|-offs(ARG) : fetch memory at ARG +|- offs address. |
eca0d916 MH |
730 | * Alias name of args: |
731 | * NAME=FETCHARG : set NAME as alias of FETCHARG. | |
93ccae7a MH |
732 | * Type of args: |
733 | * FETCHARG:TYPE : use TYPE instead of unsigned long. | |
413d37d1 | 734 | */ |
ab105a4f | 735 | struct trace_kprobe *tk = NULL; |
6212dd29 MH |
736 | int i, len, ret = 0; |
737 | bool is_return = false; | |
738 | char *symbol = NULL, *tmp = NULL; | |
739 | const char *event = NULL, *group = KPROBE_EVENT_SYSTEM; | |
696ced4f | 740 | int maxactive = 0; |
c5d343b6 | 741 | long offset = 0; |
413d37d1 | 742 | void *addr = NULL; |
4a846b44 | 743 | char buf[MAX_EVENT_NAME_LEN]; |
a1303af5 | 744 | unsigned int flags = TPARG_FL_KERNEL; |
413d37d1 | 745 | |
8b05a3a7 AR |
746 | switch (argv[0][0]) { |
747 | case 'r': | |
3a6b7666 | 748 | is_return = true; |
a1303af5 | 749 | flags |= TPARG_FL_RETURN; |
8b05a3a7 AR |
750 | break; |
751 | case 'p': | |
752 | break; | |
753 | default: | |
754 | return -ECANCELED; | |
755 | } | |
756 | if (argc < 2) | |
6212dd29 | 757 | return -ECANCELED; |
413d37d1 | 758 | |
ab105a4f MH |
759 | trace_probe_log_init("trace_kprobe", argc, argv); |
760 | ||
696ced4f | 761 | event = strchr(&argv[0][1], ':'); |
6212dd29 | 762 | if (event) |
696ced4f | 763 | event++; |
6212dd29 | 764 | |
287c038c MH |
765 | if (isdigit(argv[0][1])) { |
766 | if (!is_return) { | |
ab105a4f MH |
767 | trace_probe_log_err(1, MAXACT_NO_KPROBE); |
768 | goto parse_error; | |
287c038c | 769 | } |
6212dd29 MH |
770 | if (event) |
771 | len = event - &argv[0][1] - 1; | |
772 | else | |
773 | len = strlen(&argv[0][1]); | |
ab105a4f MH |
774 | if (len > MAX_EVENT_NAME_LEN - 1) { |
775 | trace_probe_log_err(1, BAD_MAXACT); | |
776 | goto parse_error; | |
777 | } | |
6212dd29 MH |
778 | memcpy(buf, &argv[0][1], len); |
779 | buf[len] = '\0'; | |
780 | ret = kstrtouint(buf, 0, &maxactive); | |
287c038c | 781 | if (ret || !maxactive) { |
ab105a4f MH |
782 | trace_probe_log_err(1, BAD_MAXACT); |
783 | goto parse_error; | |
696ced4f AC |
784 | } |
785 | /* kretprobes instances are iterated over via a list. The | |
786 | * maximum should stay reasonable. | |
787 | */ | |
788 | if (maxactive > KRETPROBE_MAXACTIVE_MAX) { | |
ab105a4f MH |
789 | trace_probe_log_err(1, MAXACT_TOO_BIG); |
790 | goto parse_error; | |
696ced4f AC |
791 | } |
792 | } | |
793 | ||
9e52b325 SD |
794 | /* try to parse an address. if that fails, try to read the |
795 | * input as a symbol. */ | |
796 | if (kstrtoul(argv[1], 0, (unsigned long *)&addr)) { | |
ab105a4f | 797 | trace_probe_log_set_index(1); |
6212dd29 | 798 | /* Check whether uprobe event specified */ |
ab105a4f MH |
799 | if (strchr(argv[1], '/') && strchr(argv[1], ':')) { |
800 | ret = -ECANCELED; | |
801 | goto error; | |
802 | } | |
413d37d1 | 803 | /* a symbol specified */ |
6212dd29 MH |
804 | symbol = kstrdup(argv[1], GFP_KERNEL); |
805 | if (!symbol) | |
806 | return -ENOMEM; | |
413d37d1 | 807 | /* TODO: support .init module functions */ |
8ab83f56 | 808 | ret = traceprobe_split_symbol_offset(symbol, &offset); |
c5d343b6 | 809 | if (ret || offset < 0 || offset > UINT_MAX) { |
ab105a4f MH |
810 | trace_probe_log_err(0, BAD_PROBE_ADDR); |
811 | goto parse_error; | |
e63cc239 | 812 | } |
a1303af5 MH |
813 | if (kprobe_on_func_entry(NULL, symbol, offset)) |
814 | flags |= TPARG_FL_FENTRY; | |
815 | if (offset && is_return && !(flags & TPARG_FL_FENTRY)) { | |
ab105a4f MH |
816 | trace_probe_log_err(0, BAD_RETPROBE); |
817 | goto parse_error; | |
e63cc239 | 818 | } |
413d37d1 MH |
819 | } |
820 | ||
ab105a4f | 821 | trace_probe_log_set_index(0); |
6212dd29 | 822 | if (event) { |
ab105a4f MH |
823 | ret = traceprobe_parse_event_name(&event, &group, buf, |
824 | event - argv[0]); | |
6212dd29 | 825 | if (ret) |
ab105a4f | 826 | goto parse_error; |
6212dd29 | 827 | } else { |
4263565d | 828 | /* Make a new event name */ |
4263565d | 829 | if (symbol) |
6f3cf440 | 830 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", |
4263565d MH |
831 | is_return ? 'r' : 'p', symbol, offset); |
832 | else | |
6f3cf440 | 833 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p", |
4263565d | 834 | is_return ? 'r' : 'p', addr); |
fca18a47 | 835 | sanitize_event_name(buf); |
4a846b44 MH |
836 | event = buf; |
837 | } | |
6212dd29 MH |
838 | |
839 | /* setup a probe */ | |
696ced4f | 840 | tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive, |
ab105a4f | 841 | argc - 2, is_return); |
c31ffb3f | 842 | if (IS_ERR(tk)) { |
6212dd29 | 843 | ret = PTR_ERR(tk); |
ab105a4f | 844 | /* This must return -ENOMEM, else there is a bug */ |
a039480e | 845 | WARN_ON_ONCE(ret != -ENOMEM); |
ab105a4f | 846 | goto out; /* We know tk is not allocated */ |
e63cc239 | 847 | } |
ab105a4f | 848 | argc -= 2; argv += 2; |
413d37d1 | 849 | |
413d37d1 | 850 | /* parse arguments */ |
a82378d8 | 851 | for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { |
6212dd29 MH |
852 | tmp = kstrdup(argv[i], GFP_KERNEL); |
853 | if (!tmp) { | |
ba8665d7 | 854 | ret = -ENOMEM; |
413d37d1 MH |
855 | goto error; |
856 | } | |
da34634f | 857 | |
ab105a4f | 858 | trace_probe_log_set_index(i + 2); |
6212dd29 MH |
859 | ret = traceprobe_parse_probe_arg(&tk->tp, i, tmp, flags); |
860 | kfree(tmp); | |
d00bbea9 | 861 | if (ret) |
ab105a4f | 862 | goto error; /* This can be -ENOMEM */ |
413d37d1 | 863 | } |
413d37d1 | 864 | |
f730e0f2 MH |
865 | ret = traceprobe_set_print_fmt(&tk->tp, is_return); |
866 | if (ret < 0) | |
867 | goto error; | |
868 | ||
c31ffb3f | 869 | ret = register_trace_kprobe(tk); |
ab105a4f MH |
870 | if (ret) { |
871 | trace_probe_log_set_index(1); | |
872 | if (ret == -EILSEQ) | |
873 | trace_probe_log_err(0, BAD_INSN_BNDRY); | |
874 | else if (ret == -ENOENT) | |
875 | trace_probe_log_err(0, BAD_PROBE_ADDR); | |
ca89bc07 | 876 | else if (ret != -ENOMEM && ret != -EEXIST) |
ab105a4f | 877 | trace_probe_log_err(0, FAIL_REG_PROBE); |
413d37d1 | 878 | goto error; |
ab105a4f MH |
879 | } |
880 | ||
6212dd29 | 881 | out: |
ab105a4f | 882 | trace_probe_log_clear(); |
6212dd29 MH |
883 | kfree(symbol); |
884 | return ret; | |
413d37d1 | 885 | |
ab105a4f MH |
886 | parse_error: |
887 | ret = -EINVAL; | |
413d37d1 | 888 | error: |
c31ffb3f | 889 | free_trace_kprobe(tk); |
6212dd29 | 890 | goto out; |
413d37d1 MH |
891 | } |
892 | ||
6212dd29 | 893 | static int create_or_delete_trace_kprobe(int argc, char **argv) |
413d37d1 | 894 | { |
6212dd29 | 895 | int ret; |
02ca1521 | 896 | |
6212dd29 MH |
897 | if (argv[0][0] == '-') |
898 | return dyn_event_release(argc, argv, &trace_kprobe_ops); | |
413d37d1 | 899 | |
6212dd29 MH |
900 | ret = trace_kprobe_create(argc, (const char **)argv); |
901 | return ret == -ECANCELED ? -EINVAL : ret; | |
413d37d1 MH |
902 | } |
903 | ||
29a15481 | 904 | static int trace_kprobe_run_command(struct dynevent_cmd *cmd) |
2a588dd1 | 905 | { |
2b90927c | 906 | return trace_run_command(cmd->seq.buffer, create_or_delete_trace_kprobe); |
2a588dd1 TZ |
907 | } |
908 | ||
909 | /** | |
910 | * kprobe_event_cmd_init - Initialize a kprobe event command object | |
911 | * @cmd: A pointer to the dynevent_cmd struct representing the new event | |
912 | * @buf: A pointer to the buffer used to build the command | |
913 | * @maxlen: The length of the buffer passed in @buf | |
914 | * | |
915 | * Initialize a synthetic event command object. Use this before | |
916 | * calling any of the other kprobe_event functions. | |
917 | */ | |
918 | void kprobe_event_cmd_init(struct dynevent_cmd *cmd, char *buf, int maxlen) | |
919 | { | |
920 | dynevent_cmd_init(cmd, buf, maxlen, DYNEVENT_TYPE_KPROBE, | |
29a15481 | 921 | trace_kprobe_run_command); |
2a588dd1 TZ |
922 | } |
923 | EXPORT_SYMBOL_GPL(kprobe_event_cmd_init); | |
924 | ||
925 | /** | |
926 | * __kprobe_event_gen_cmd_start - Generate a kprobe event command from arg list | |
927 | * @cmd: A pointer to the dynevent_cmd struct representing the new event | |
928 | * @name: The name of the kprobe event | |
929 | * @loc: The location of the kprobe event | |
930 | * @kretprobe: Is this a return probe? | |
931 | * @args: Variable number of arg (pairs), one pair for each field | |
932 | * | |
933 | * NOTE: Users normally won't want to call this function directly, but | |
934 | * rather use the kprobe_event_gen_cmd_start() wrapper, which automatically | |
935 | * adds a NULL to the end of the arg list. If this function is used | |
936 | * directly, make sure the last arg in the variable arg list is NULL. | |
937 | * | |
938 | * Generate a kprobe event command to be executed by | |
939 | * kprobe_event_gen_cmd_end(). This function can be used to generate the | |
940 | * complete command or only the first part of it; in the latter case, | |
941 | * kprobe_event_add_fields() can be used to add more fields following this. | |
942 | * | |
5b4dcd2d MH |
943 | * Unlikely the synth_event_gen_cmd_start(), @loc must be specified. This |
944 | * returns -EINVAL if @loc == NULL. | |
945 | * | |
2a588dd1 TZ |
946 | * Return: 0 if successful, error otherwise. |
947 | */ | |
948 | int __kprobe_event_gen_cmd_start(struct dynevent_cmd *cmd, bool kretprobe, | |
949 | const char *name, const char *loc, ...) | |
950 | { | |
951 | char buf[MAX_EVENT_NAME_LEN]; | |
952 | struct dynevent_arg arg; | |
953 | va_list args; | |
954 | int ret; | |
955 | ||
956 | if (cmd->type != DYNEVENT_TYPE_KPROBE) | |
957 | return -EINVAL; | |
958 | ||
5b4dcd2d MH |
959 | if (!loc) |
960 | return -EINVAL; | |
961 | ||
2a588dd1 TZ |
962 | if (kretprobe) |
963 | snprintf(buf, MAX_EVENT_NAME_LEN, "r:kprobes/%s", name); | |
964 | else | |
965 | snprintf(buf, MAX_EVENT_NAME_LEN, "p:kprobes/%s", name); | |
966 | ||
967 | ret = dynevent_str_add(cmd, buf); | |
968 | if (ret) | |
969 | return ret; | |
970 | ||
74403b6c | 971 | dynevent_arg_init(&arg, 0); |
2a588dd1 | 972 | arg.str = loc; |
74403b6c | 973 | ret = dynevent_arg_add(cmd, &arg, NULL); |
2a588dd1 TZ |
974 | if (ret) |
975 | return ret; | |
976 | ||
977 | va_start(args, loc); | |
978 | for (;;) { | |
979 | const char *field; | |
980 | ||
981 | field = va_arg(args, const char *); | |
982 | if (!field) | |
983 | break; | |
984 | ||
985 | if (++cmd->n_fields > MAX_TRACE_ARGS) { | |
986 | ret = -EINVAL; | |
987 | break; | |
988 | } | |
989 | ||
990 | arg.str = field; | |
74403b6c | 991 | ret = dynevent_arg_add(cmd, &arg, NULL); |
2a588dd1 TZ |
992 | if (ret) |
993 | break; | |
994 | } | |
995 | va_end(args); | |
996 | ||
997 | return ret; | |
998 | } | |
999 | EXPORT_SYMBOL_GPL(__kprobe_event_gen_cmd_start); | |
1000 | ||
1001 | /** | |
1002 | * __kprobe_event_add_fields - Add probe fields to a kprobe command from arg list | |
1003 | * @cmd: A pointer to the dynevent_cmd struct representing the new event | |
1004 | * @args: Variable number of arg (pairs), one pair for each field | |
1005 | * | |
1006 | * NOTE: Users normally won't want to call this function directly, but | |
1007 | * rather use the kprobe_event_add_fields() wrapper, which | |
1008 | * automatically adds a NULL to the end of the arg list. If this | |
1009 | * function is used directly, make sure the last arg in the variable | |
1010 | * arg list is NULL. | |
1011 | * | |
1012 | * Add probe fields to an existing kprobe command using a variable | |
1013 | * list of args. Fields are added in the same order they're listed. | |
1014 | * | |
1015 | * Return: 0 if successful, error otherwise. | |
1016 | */ | |
1017 | int __kprobe_event_add_fields(struct dynevent_cmd *cmd, ...) | |
1018 | { | |
1019 | struct dynevent_arg arg; | |
1020 | va_list args; | |
10f129cb | 1021 | int ret = 0; |
2a588dd1 TZ |
1022 | |
1023 | if (cmd->type != DYNEVENT_TYPE_KPROBE) | |
1024 | return -EINVAL; | |
1025 | ||
74403b6c | 1026 | dynevent_arg_init(&arg, 0); |
2a588dd1 TZ |
1027 | |
1028 | va_start(args, cmd); | |
1029 | for (;;) { | |
1030 | const char *field; | |
1031 | ||
1032 | field = va_arg(args, const char *); | |
1033 | if (!field) | |
1034 | break; | |
1035 | ||
1036 | if (++cmd->n_fields > MAX_TRACE_ARGS) { | |
1037 | ret = -EINVAL; | |
1038 | break; | |
1039 | } | |
1040 | ||
1041 | arg.str = field; | |
74403b6c | 1042 | ret = dynevent_arg_add(cmd, &arg, NULL); |
2a588dd1 TZ |
1043 | if (ret) |
1044 | break; | |
1045 | } | |
1046 | va_end(args); | |
1047 | ||
1048 | return ret; | |
1049 | } | |
1050 | EXPORT_SYMBOL_GPL(__kprobe_event_add_fields); | |
1051 | ||
1052 | /** | |
1053 | * kprobe_event_delete - Delete a kprobe event | |
1054 | * @name: The name of the kprobe event to delete | |
1055 | * | |
1056 | * Delete a kprobe event with the give @name from kernel code rather | |
1057 | * than directly from the command line. | |
1058 | * | |
1059 | * Return: 0 if successful, error otherwise. | |
1060 | */ | |
1061 | int kprobe_event_delete(const char *name) | |
1062 | { | |
1063 | char buf[MAX_EVENT_NAME_LEN]; | |
1064 | ||
1065 | snprintf(buf, MAX_EVENT_NAME_LEN, "-:%s", name); | |
1066 | ||
1067 | return trace_run_command(buf, create_or_delete_trace_kprobe); | |
1068 | } | |
1069 | EXPORT_SYMBOL_GPL(kprobe_event_delete); | |
1070 | ||
6212dd29 | 1071 | static int trace_kprobe_release(struct dyn_event *ev) |
413d37d1 | 1072 | { |
6212dd29 MH |
1073 | struct trace_kprobe *tk = to_trace_kprobe(ev); |
1074 | int ret = unregister_trace_kprobe(tk); | |
413d37d1 | 1075 | |
6212dd29 MH |
1076 | if (!ret) |
1077 | free_trace_kprobe(tk); | |
1078 | return ret; | |
413d37d1 MH |
1079 | } |
1080 | ||
6212dd29 | 1081 | static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev) |
413d37d1 | 1082 | { |
6212dd29 | 1083 | struct trace_kprobe *tk = to_trace_kprobe(ev); |
93ccae7a | 1084 | int i; |
413d37d1 | 1085 | |
fa6f0cc7 | 1086 | seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p'); |
6a13a0d7 MH |
1087 | if (trace_kprobe_is_return(tk) && tk->rp.maxactive) |
1088 | seq_printf(m, "%d", tk->rp.maxactive); | |
b55ce203 MH |
1089 | seq_printf(m, ":%s/%s", trace_probe_group_name(&tk->tp), |
1090 | trace_probe_name(&tk->tp)); | |
413d37d1 | 1091 | |
c31ffb3f NK |
1092 | if (!tk->symbol) |
1093 | seq_printf(m, " 0x%p", tk->rp.kp.addr); | |
1094 | else if (tk->rp.kp.offset) | |
1095 | seq_printf(m, " %s+%u", trace_kprobe_symbol(tk), | |
1096 | tk->rp.kp.offset); | |
413d37d1 | 1097 | else |
c31ffb3f | 1098 | seq_printf(m, " %s", trace_kprobe_symbol(tk)); |
413d37d1 | 1099 | |
c31ffb3f NK |
1100 | for (i = 0; i < tk->tp.nr_args; i++) |
1101 | seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm); | |
fa6f0cc7 | 1102 | seq_putc(m, '\n'); |
93ccae7a | 1103 | |
413d37d1 MH |
1104 | return 0; |
1105 | } | |
1106 | ||
6212dd29 MH |
1107 | static int probes_seq_show(struct seq_file *m, void *v) |
1108 | { | |
1109 | struct dyn_event *ev = v; | |
1110 | ||
1111 | if (!is_trace_kprobe(ev)) | |
1112 | return 0; | |
1113 | ||
1114 | return trace_kprobe_show(m, ev); | |
1115 | } | |
1116 | ||
413d37d1 | 1117 | static const struct seq_operations probes_seq_op = { |
6212dd29 MH |
1118 | .start = dyn_event_seq_start, |
1119 | .next = dyn_event_seq_next, | |
1120 | .stop = dyn_event_seq_stop, | |
413d37d1 MH |
1121 | .show = probes_seq_show |
1122 | }; | |
1123 | ||
1124 | static int probes_open(struct inode *inode, struct file *file) | |
1125 | { | |
02ca1521 MH |
1126 | int ret; |
1127 | ||
17911ff3 SRV |
1128 | ret = security_locked_down(LOCKDOWN_TRACEFS); |
1129 | if (ret) | |
1130 | return ret; | |
1131 | ||
02ca1521 | 1132 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
6212dd29 | 1133 | ret = dyn_events_release_all(&trace_kprobe_ops); |
02ca1521 MH |
1134 | if (ret < 0) |
1135 | return ret; | |
1136 | } | |
413d37d1 MH |
1137 | |
1138 | return seq_open(file, &probes_seq_op); | |
1139 | } | |
1140 | ||
413d37d1 MH |
1141 | static ssize_t probes_write(struct file *file, const char __user *buffer, |
1142 | size_t count, loff_t *ppos) | |
1143 | { | |
7e465baa | 1144 | return trace_parse_run_command(file, buffer, count, ppos, |
6212dd29 | 1145 | create_or_delete_trace_kprobe); |
413d37d1 MH |
1146 | } |
1147 | ||
1148 | static const struct file_operations kprobe_events_ops = { | |
1149 | .owner = THIS_MODULE, | |
1150 | .open = probes_open, | |
1151 | .read = seq_read, | |
1152 | .llseek = seq_lseek, | |
1153 | .release = seq_release, | |
1154 | .write = probes_write, | |
1155 | }; | |
1156 | ||
cd7e7bd5 MH |
1157 | /* Probes profiling interfaces */ |
1158 | static int probes_profile_seq_show(struct seq_file *m, void *v) | |
1159 | { | |
6212dd29 MH |
1160 | struct dyn_event *ev = v; |
1161 | struct trace_kprobe *tk; | |
cd7e7bd5 | 1162 | |
6212dd29 MH |
1163 | if (!is_trace_kprobe(ev)) |
1164 | return 0; | |
cd7e7bd5 | 1165 | |
6212dd29 | 1166 | tk = to_trace_kprobe(ev); |
de7b2973 | 1167 | seq_printf(m, " %-44s %15lu %15lu\n", |
b55ce203 | 1168 | trace_probe_name(&tk->tp), |
f18f97ac | 1169 | trace_kprobe_nhit(tk), |
c31ffb3f | 1170 | tk->rp.kp.nmissed); |
cd7e7bd5 MH |
1171 | |
1172 | return 0; | |
1173 | } | |
1174 | ||
1175 | static const struct seq_operations profile_seq_op = { | |
6212dd29 MH |
1176 | .start = dyn_event_seq_start, |
1177 | .next = dyn_event_seq_next, | |
1178 | .stop = dyn_event_seq_stop, | |
cd7e7bd5 MH |
1179 | .show = probes_profile_seq_show |
1180 | }; | |
1181 | ||
1182 | static int profile_open(struct inode *inode, struct file *file) | |
1183 | { | |
17911ff3 SRV |
1184 | int ret; |
1185 | ||
1186 | ret = security_locked_down(LOCKDOWN_TRACEFS); | |
1187 | if (ret) | |
1188 | return ret; | |
1189 | ||
cd7e7bd5 MH |
1190 | return seq_open(file, &profile_seq_op); |
1191 | } | |
1192 | ||
1193 | static const struct file_operations kprobe_profile_ops = { | |
1194 | .owner = THIS_MODULE, | |
1195 | .open = profile_open, | |
1196 | .read = seq_read, | |
1197 | .llseek = seq_lseek, | |
1198 | .release = seq_release, | |
1199 | }; | |
1200 | ||
53305928 MH |
1201 | /* Kprobe specific fetch functions */ |
1202 | ||
9de1fec5 CH |
1203 | /* Return the length of string -- including null terminal byte */ |
1204 | static nokprobe_inline int | |
1205 | fetch_store_strlen_user(unsigned long addr) | |
1206 | { | |
1207 | const void __user *uaddr = (__force const void __user *)addr; | |
1208 | ||
1209 | return strnlen_user_nofault(uaddr, MAX_STRING_SIZE); | |
1210 | } | |
1211 | ||
53305928 | 1212 | /* Return the length of string -- including null terminal byte */ |
9178412d MH |
1213 | static nokprobe_inline int |
1214 | fetch_store_strlen(unsigned long addr) | |
53305928 | 1215 | { |
53305928 MH |
1216 | int ret, len = 0; |
1217 | u8 c; | |
1218 | ||
9de1fec5 CH |
1219 | #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE |
1220 | if (addr < TASK_SIZE) | |
1221 | return fetch_store_strlen_user(addr); | |
1222 | #endif | |
1223 | ||
53305928 | 1224 | do { |
9de1fec5 | 1225 | ret = probe_kernel_read_strict(&c, (u8 *)addr + len, 1); |
53305928 MH |
1226 | len++; |
1227 | } while (c && ret == 0 && len < MAX_STRING_SIZE); | |
1228 | ||
9178412d | 1229 | return (ret < 0) ? ret : len; |
53305928 MH |
1230 | } |
1231 | ||
1232 | /* | |
9de1fec5 CH |
1233 | * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf |
1234 | * with max length and relative data location. | |
53305928 | 1235 | */ |
9178412d | 1236 | static nokprobe_inline int |
9de1fec5 | 1237 | fetch_store_string_user(unsigned long addr, void *dest, void *base) |
53305928 | 1238 | { |
9de1fec5 | 1239 | const void __user *uaddr = (__force const void __user *)addr; |
9178412d | 1240 | int maxlen = get_loc_len(*(u32 *)dest); |
88903c46 | 1241 | void *__dest; |
53305928 MH |
1242 | long ret; |
1243 | ||
9178412d MH |
1244 | if (unlikely(!maxlen)) |
1245 | return -ENOMEM; | |
88903c46 MH |
1246 | |
1247 | __dest = get_loc_data(dest, base); | |
1248 | ||
9de1fec5 | 1249 | ret = strncpy_from_user_nofault(__dest, uaddr, maxlen); |
88903c46 MH |
1250 | if (ret >= 0) |
1251 | *(u32 *)dest = make_data_loc(ret, __dest - base); | |
1252 | ||
1253 | return ret; | |
1254 | } | |
53305928 | 1255 | |
88903c46 | 1256 | /* |
9de1fec5 CH |
1257 | * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max |
1258 | * length and relative data location. | |
88903c46 MH |
1259 | */ |
1260 | static nokprobe_inline int | |
9de1fec5 | 1261 | fetch_store_string(unsigned long addr, void *dest, void *base) |
88903c46 | 1262 | { |
88903c46 MH |
1263 | int maxlen = get_loc_len(*(u32 *)dest); |
1264 | void *__dest; | |
1265 | long ret; | |
1266 | ||
9de1fec5 CH |
1267 | #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE |
1268 | if ((unsigned long)addr < TASK_SIZE) | |
1269 | return fetch_store_string_user(addr, dest, base); | |
1270 | #endif | |
1271 | ||
88903c46 MH |
1272 | if (unlikely(!maxlen)) |
1273 | return -ENOMEM; | |
1274 | ||
1275 | __dest = get_loc_data(dest, base); | |
1276 | ||
9de1fec5 CH |
1277 | /* |
1278 | * Try to get string again, since the string can be changed while | |
1279 | * probing. | |
1280 | */ | |
1281 | ret = strncpy_from_kernel_nofault(__dest, (void *)addr, maxlen); | |
9178412d | 1282 | if (ret >= 0) |
88903c46 MH |
1283 | *(u32 *)dest = make_data_loc(ret, __dest - base); |
1284 | ||
9178412d | 1285 | return ret; |
53305928 MH |
1286 | } |
1287 | ||
e65f7ae7 MH |
1288 | static nokprobe_inline int |
1289 | probe_mem_read_user(void *dest, void *src, size_t size) | |
1290 | { | |
539b75b2 MH |
1291 | const void __user *uaddr = (__force const void __user *)src; |
1292 | ||
1293 | return probe_user_read(dest, uaddr, size); | |
e65f7ae7 MH |
1294 | } |
1295 | ||
9de1fec5 CH |
1296 | static nokprobe_inline int |
1297 | probe_mem_read(void *dest, void *src, size_t size) | |
1298 | { | |
1299 | #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE | |
1300 | if ((unsigned long)src < TASK_SIZE) | |
1301 | return probe_mem_read_user(dest, src, size); | |
1302 | #endif | |
1303 | return probe_kernel_read_strict(dest, src, size); | |
1304 | } | |
1305 | ||
53305928 MH |
1306 | /* Note that we don't verify it, since the code does not come from user space */ |
1307 | static int | |
1308 | process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest, | |
9178412d | 1309 | void *base) |
53305928 MH |
1310 | { |
1311 | unsigned long val; | |
53305928 | 1312 | |
a6682814 | 1313 | retry: |
53305928 MH |
1314 | /* 1st stage: get value from context */ |
1315 | switch (code->op) { | |
1316 | case FETCH_OP_REG: | |
1317 | val = regs_get_register(regs, code->param); | |
1318 | break; | |
1319 | case FETCH_OP_STACK: | |
1320 | val = regs_get_kernel_stack_nth(regs, code->param); | |
1321 | break; | |
1322 | case FETCH_OP_STACKP: | |
1323 | val = kernel_stack_pointer(regs); | |
1324 | break; | |
1325 | case FETCH_OP_RETVAL: | |
1326 | val = regs_return_value(regs); | |
1327 | break; | |
1328 | case FETCH_OP_IMM: | |
1329 | val = code->immediate; | |
1330 | break; | |
1331 | case FETCH_OP_COMM: | |
1332 | val = (unsigned long)current->comm; | |
1333 | break; | |
a42e3c4d MH |
1334 | case FETCH_OP_DATA: |
1335 | val = (unsigned long)code->data; | |
1336 | break; | |
a1303af5 MH |
1337 | #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API |
1338 | case FETCH_OP_ARG: | |
1339 | val = regs_get_kernel_argument(regs, code->param); | |
1340 | break; | |
1341 | #endif | |
a6682814 MH |
1342 | case FETCH_NOP_SYMBOL: /* Ignore a place holder */ |
1343 | code++; | |
1344 | goto retry; | |
53305928 MH |
1345 | default: |
1346 | return -EILSEQ; | |
1347 | } | |
1348 | code++; | |
1349 | ||
9b960a38 | 1350 | return process_fetch_insn_bottom(code, val, dest, base); |
53305928 MH |
1351 | } |
1352 | NOKPROBE_SYMBOL(process_fetch_insn) | |
1353 | ||
413d37d1 | 1354 | /* Kprobe handler */ |
3da0f180 | 1355 | static nokprobe_inline void |
c31ffb3f | 1356 | __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs, |
7f1d2f82 | 1357 | struct trace_event_file *trace_file) |
413d37d1 | 1358 | { |
93ccae7a | 1359 | struct kprobe_trace_entry_head *entry; |
e3dc9f89 | 1360 | struct trace_event_call *call = trace_probe_event_call(&tk->tp); |
8cfcf155 MH |
1361 | struct trace_event_buffer fbuffer; |
1362 | int dsize; | |
413d37d1 | 1363 | |
7f1d2f82 | 1364 | WARN_ON(call != trace_file->event_call); |
41a7dd42 | 1365 | |
09a5059a | 1366 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 1367 | return; |
b8820084 | 1368 | |
8cfcf155 MH |
1369 | local_save_flags(fbuffer.flags); |
1370 | fbuffer.pc = preempt_count(); | |
1371 | fbuffer.trace_file = trace_file; | |
413d37d1 | 1372 | |
c31ffb3f | 1373 | dsize = __get_data_size(&tk->tp, regs); |
413d37d1 | 1374 | |
8cfcf155 MH |
1375 | fbuffer.event = |
1376 | trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file, | |
1377 | call->event.type, | |
1378 | sizeof(*entry) + tk->tp.size + dsize, | |
1379 | fbuffer.flags, fbuffer.pc); | |
1380 | if (!fbuffer.event) | |
1e12a4a7 | 1381 | return; |
413d37d1 | 1382 | |
8cfcf155 MH |
1383 | fbuffer.regs = regs; |
1384 | entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); | |
c31ffb3f | 1385 | entry->ip = (unsigned long)tk->rp.kp.addr; |
9178412d | 1386 | store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize); |
413d37d1 | 1387 | |
8cfcf155 | 1388 | trace_event_buffer_commit(&fbuffer); |
413d37d1 MH |
1389 | } |
1390 | ||
3da0f180 | 1391 | static void |
c31ffb3f | 1392 | kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs) |
41a7dd42 | 1393 | { |
b04d52e3 | 1394 | struct event_file_link *link; |
41a7dd42 | 1395 | |
b5f935ee | 1396 | trace_probe_for_each_link_rcu(link, &tk->tp) |
c31ffb3f | 1397 | __kprobe_trace_func(tk, regs, link->file); |
41a7dd42 | 1398 | } |
3da0f180 | 1399 | NOKPROBE_SYMBOL(kprobe_trace_func); |
41a7dd42 | 1400 | |
413d37d1 | 1401 | /* Kretprobe handler */ |
3da0f180 | 1402 | static nokprobe_inline void |
c31ffb3f | 1403 | __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
41a7dd42 | 1404 | struct pt_regs *regs, |
7f1d2f82 | 1405 | struct trace_event_file *trace_file) |
413d37d1 | 1406 | { |
93ccae7a | 1407 | struct kretprobe_trace_entry_head *entry; |
8cfcf155 | 1408 | struct trace_event_buffer fbuffer; |
e3dc9f89 | 1409 | struct trace_event_call *call = trace_probe_event_call(&tk->tp); |
8cfcf155 | 1410 | int dsize; |
413d37d1 | 1411 | |
7f1d2f82 | 1412 | WARN_ON(call != trace_file->event_call); |
41a7dd42 | 1413 | |
09a5059a | 1414 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 1415 | return; |
b8820084 | 1416 | |
8cfcf155 MH |
1417 | local_save_flags(fbuffer.flags); |
1418 | fbuffer.pc = preempt_count(); | |
1419 | fbuffer.trace_file = trace_file; | |
413d37d1 | 1420 | |
c31ffb3f | 1421 | dsize = __get_data_size(&tk->tp, regs); |
8cfcf155 MH |
1422 | fbuffer.event = |
1423 | trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file, | |
1424 | call->event.type, | |
1425 | sizeof(*entry) + tk->tp.size + dsize, | |
1426 | fbuffer.flags, fbuffer.pc); | |
1427 | if (!fbuffer.event) | |
1e12a4a7 | 1428 | return; |
413d37d1 | 1429 | |
8cfcf155 MH |
1430 | fbuffer.regs = regs; |
1431 | entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); | |
c31ffb3f | 1432 | entry->func = (unsigned long)tk->rp.kp.addr; |
413d37d1 | 1433 | entry->ret_ip = (unsigned long)ri->ret_addr; |
9178412d | 1434 | store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize); |
413d37d1 | 1435 | |
8cfcf155 | 1436 | trace_event_buffer_commit(&fbuffer); |
413d37d1 MH |
1437 | } |
1438 | ||
3da0f180 | 1439 | static void |
c31ffb3f | 1440 | kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
41a7dd42 MH |
1441 | struct pt_regs *regs) |
1442 | { | |
b04d52e3 | 1443 | struct event_file_link *link; |
41a7dd42 | 1444 | |
b5f935ee | 1445 | trace_probe_for_each_link_rcu(link, &tk->tp) |
c31ffb3f | 1446 | __kretprobe_trace_func(tk, ri, regs, link->file); |
41a7dd42 | 1447 | } |
3da0f180 | 1448 | NOKPROBE_SYMBOL(kretprobe_trace_func); |
41a7dd42 | 1449 | |
413d37d1 | 1450 | /* Event entry printers */ |
b62fdd97 | 1451 | static enum print_line_t |
a9a57763 SR |
1452 | print_kprobe_event(struct trace_iterator *iter, int flags, |
1453 | struct trace_event *event) | |
413d37d1 | 1454 | { |
93ccae7a | 1455 | struct kprobe_trace_entry_head *field; |
413d37d1 | 1456 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1457 | struct trace_probe *tp; |
413d37d1 | 1458 | |
93ccae7a | 1459 | field = (struct kprobe_trace_entry_head *)iter->ent; |
60d53e2c MH |
1460 | tp = trace_probe_primary_from_call( |
1461 | container_of(event, struct trace_event_call, event)); | |
1462 | if (WARN_ON_ONCE(!tp)) | |
1463 | goto out; | |
413d37d1 | 1464 | |
b55ce203 | 1465 | trace_seq_printf(s, "%s: (", trace_probe_name(tp)); |
6e9f23d1 | 1466 | |
413d37d1 | 1467 | if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) |
85224da0 | 1468 | goto out; |
413d37d1 | 1469 | |
85224da0 | 1470 | trace_seq_putc(s, ')'); |
413d37d1 | 1471 | |
56de7630 MH |
1472 | if (print_probe_args(s, tp->args, tp->nr_args, |
1473 | (u8 *)&field[1], field) < 0) | |
1474 | goto out; | |
413d37d1 | 1475 | |
85224da0 SRRH |
1476 | trace_seq_putc(s, '\n'); |
1477 | out: | |
1478 | return trace_handle_return(s); | |
413d37d1 MH |
1479 | } |
1480 | ||
b62fdd97 | 1481 | static enum print_line_t |
a9a57763 SR |
1482 | print_kretprobe_event(struct trace_iterator *iter, int flags, |
1483 | struct trace_event *event) | |
413d37d1 | 1484 | { |
93ccae7a | 1485 | struct kretprobe_trace_entry_head *field; |
413d37d1 | 1486 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1487 | struct trace_probe *tp; |
413d37d1 | 1488 | |
93ccae7a | 1489 | field = (struct kretprobe_trace_entry_head *)iter->ent; |
60d53e2c MH |
1490 | tp = trace_probe_primary_from_call( |
1491 | container_of(event, struct trace_event_call, event)); | |
1492 | if (WARN_ON_ONCE(!tp)) | |
1493 | goto out; | |
413d37d1 | 1494 | |
b55ce203 | 1495 | trace_seq_printf(s, "%s: (", trace_probe_name(tp)); |
6e9f23d1 | 1496 | |
413d37d1 | 1497 | if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) |
85224da0 | 1498 | goto out; |
413d37d1 | 1499 | |
85224da0 | 1500 | trace_seq_puts(s, " <- "); |
413d37d1 MH |
1501 | |
1502 | if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) | |
85224da0 | 1503 | goto out; |
413d37d1 | 1504 | |
85224da0 | 1505 | trace_seq_putc(s, ')'); |
413d37d1 | 1506 | |
56de7630 MH |
1507 | if (print_probe_args(s, tp->args, tp->nr_args, |
1508 | (u8 *)&field[1], field) < 0) | |
1509 | goto out; | |
413d37d1 | 1510 | |
85224da0 | 1511 | trace_seq_putc(s, '\n'); |
413d37d1 | 1512 | |
85224da0 SRRH |
1513 | out: |
1514 | return trace_handle_return(s); | |
413d37d1 MH |
1515 | } |
1516 | ||
413d37d1 | 1517 | |
2425bcb9 | 1518 | static int kprobe_event_define_fields(struct trace_event_call *event_call) |
413d37d1 | 1519 | { |
eeb07b06 | 1520 | int ret; |
93ccae7a | 1521 | struct kprobe_trace_entry_head field; |
60d53e2c MH |
1522 | struct trace_probe *tp; |
1523 | ||
1524 | tp = trace_probe_primary_from_call(event_call); | |
1525 | if (WARN_ON_ONCE(!tp)) | |
1526 | return -ENOENT; | |
413d37d1 | 1527 | |
a703d946 | 1528 | DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); |
c31ffb3f | 1529 | |
60d53e2c | 1530 | return traceprobe_define_arg_fields(event_call, sizeof(field), tp); |
413d37d1 MH |
1531 | } |
1532 | ||
2425bcb9 | 1533 | static int kretprobe_event_define_fields(struct trace_event_call *event_call) |
413d37d1 | 1534 | { |
eeb07b06 | 1535 | int ret; |
93ccae7a | 1536 | struct kretprobe_trace_entry_head field; |
60d53e2c MH |
1537 | struct trace_probe *tp; |
1538 | ||
1539 | tp = trace_probe_primary_from_call(event_call); | |
1540 | if (WARN_ON_ONCE(!tp)) | |
1541 | return -ENOENT; | |
413d37d1 | 1542 | |
a703d946 MH |
1543 | DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); |
1544 | DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); | |
c31ffb3f | 1545 | |
60d53e2c | 1546 | return traceprobe_define_arg_fields(event_call, sizeof(field), tp); |
413d37d1 MH |
1547 | } |
1548 | ||
07b139c8 | 1549 | #ifdef CONFIG_PERF_EVENTS |
e08d1c65 MH |
1550 | |
1551 | /* Kprobe profile handler */ | |
9802d865 | 1552 | static int |
c31ffb3f | 1553 | kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) |
e08d1c65 | 1554 | { |
e3dc9f89 | 1555 | struct trace_event_call *call = trace_probe_event_call(&tk->tp); |
93ccae7a | 1556 | struct kprobe_trace_entry_head *entry; |
1c024eca | 1557 | struct hlist_head *head; |
e09c8614 | 1558 | int size, __size, dsize; |
4ed7c92d | 1559 | int rctx; |
e08d1c65 | 1560 | |
9802d865 | 1561 | if (bpf_prog_array_valid(call)) { |
66665ad2 | 1562 | unsigned long orig_ip = instruction_pointer(regs); |
9802d865 JB |
1563 | int ret; |
1564 | ||
1565 | ret = trace_call_bpf(call, regs); | |
1566 | ||
1567 | /* | |
1568 | * We need to check and see if we modified the pc of the | |
cce188bd MH |
1569 | * pt_regs, and if so return 1 so that we don't do the |
1570 | * single stepping. | |
9802d865 | 1571 | */ |
cce188bd | 1572 | if (orig_ip != instruction_pointer(regs)) |
9802d865 | 1573 | return 1; |
9802d865 JB |
1574 | if (!ret) |
1575 | return 0; | |
1576 | } | |
2541517c | 1577 | |
288e984e ON |
1578 | head = this_cpu_ptr(call->perf_events); |
1579 | if (hlist_empty(head)) | |
9802d865 | 1580 | return 0; |
288e984e | 1581 | |
c31ffb3f NK |
1582 | dsize = __get_data_size(&tk->tp, regs); |
1583 | __size = sizeof(*entry) + tk->tp.size + dsize; | |
74ebb63e MH |
1584 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1585 | size -= sizeof(u32); | |
ce71b9df | 1586 | |
1e1dcd93 | 1587 | entry = perf_trace_buf_alloc(size, NULL, &rctx); |
430ad5a6 | 1588 | if (!entry) |
9802d865 | 1589 | return 0; |
a1a138d0 | 1590 | |
c31ffb3f | 1591 | entry->ip = (unsigned long)tk->rp.kp.addr; |
e09c8614 | 1592 | memset(&entry[1], 0, dsize); |
9178412d | 1593 | store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize); |
1e1dcd93 | 1594 | perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, |
8fd0fbbe | 1595 | head, NULL); |
9802d865 | 1596 | return 0; |
e08d1c65 | 1597 | } |
3da0f180 | 1598 | NOKPROBE_SYMBOL(kprobe_perf_func); |
e08d1c65 MH |
1599 | |
1600 | /* Kretprobe profile handler */ | |
3da0f180 | 1601 | static void |
c31ffb3f | 1602 | kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
2b106aab | 1603 | struct pt_regs *regs) |
e08d1c65 | 1604 | { |
e3dc9f89 | 1605 | struct trace_event_call *call = trace_probe_event_call(&tk->tp); |
93ccae7a | 1606 | struct kretprobe_trace_entry_head *entry; |
1c024eca | 1607 | struct hlist_head *head; |
e09c8614 | 1608 | int size, __size, dsize; |
4ed7c92d | 1609 | int rctx; |
e08d1c65 | 1610 | |
e87c6bc3 | 1611 | if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs)) |
2541517c AS |
1612 | return; |
1613 | ||
288e984e ON |
1614 | head = this_cpu_ptr(call->perf_events); |
1615 | if (hlist_empty(head)) | |
1616 | return; | |
1617 | ||
c31ffb3f NK |
1618 | dsize = __get_data_size(&tk->tp, regs); |
1619 | __size = sizeof(*entry) + tk->tp.size + dsize; | |
74ebb63e MH |
1620 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1621 | size -= sizeof(u32); | |
444a2a3b | 1622 | |
1e1dcd93 | 1623 | entry = perf_trace_buf_alloc(size, NULL, &rctx); |
430ad5a6 | 1624 | if (!entry) |
1e12a4a7 | 1625 | return; |
e08d1c65 | 1626 | |
c31ffb3f | 1627 | entry->func = (unsigned long)tk->rp.kp.addr; |
a1a138d0 | 1628 | entry->ret_ip = (unsigned long)ri->ret_addr; |
9178412d | 1629 | store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize); |
1e1dcd93 | 1630 | perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, |
8fd0fbbe | 1631 | head, NULL); |
e08d1c65 | 1632 | } |
3da0f180 | 1633 | NOKPROBE_SYMBOL(kretprobe_perf_func); |
41bdc4b4 YS |
1634 | |
1635 | int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type, | |
1636 | const char **symbol, u64 *probe_offset, | |
1637 | u64 *probe_addr, bool perf_type_tracepoint) | |
1638 | { | |
1639 | const char *pevent = trace_event_name(event->tp_event); | |
1640 | const char *group = event->tp_event->class->system; | |
1641 | struct trace_kprobe *tk; | |
1642 | ||
1643 | if (perf_type_tracepoint) | |
1644 | tk = find_trace_kprobe(pevent, group); | |
1645 | else | |
1646 | tk = event->tp_event->data; | |
1647 | if (!tk) | |
1648 | return -EINVAL; | |
1649 | ||
1650 | *fd_type = trace_kprobe_is_return(tk) ? BPF_FD_TYPE_KRETPROBE | |
1651 | : BPF_FD_TYPE_KPROBE; | |
1652 | if (tk->symbol) { | |
1653 | *symbol = tk->symbol; | |
1654 | *probe_offset = tk->rp.kp.offset; | |
1655 | *probe_addr = 0; | |
1656 | } else { | |
1657 | *symbol = NULL; | |
1658 | *probe_offset = 0; | |
1659 | *probe_addr = (unsigned long)tk->rp.kp.addr; | |
1660 | } | |
1661 | return 0; | |
1662 | } | |
07b139c8 | 1663 | #endif /* CONFIG_PERF_EVENTS */ |
50d78056 | 1664 | |
3fe3d619 ON |
1665 | /* |
1666 | * called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex. | |
1667 | * | |
1668 | * kprobe_trace_self_tests_init() does enable_trace_probe/disable_trace_probe | |
1669 | * lockless, but we can't race with this __init function. | |
1670 | */ | |
2425bcb9 | 1671 | static int kprobe_register(struct trace_event_call *event, |
fbc1963d | 1672 | enum trace_reg type, void *data) |
2239291a | 1673 | { |
7f1d2f82 | 1674 | struct trace_event_file *file = data; |
1538f888 | 1675 | |
2239291a SR |
1676 | switch (type) { |
1677 | case TRACE_REG_REGISTER: | |
60d53e2c | 1678 | return enable_trace_kprobe(event, file); |
2239291a | 1679 | case TRACE_REG_UNREGISTER: |
60d53e2c | 1680 | return disable_trace_kprobe(event, file); |
2239291a SR |
1681 | |
1682 | #ifdef CONFIG_PERF_EVENTS | |
1683 | case TRACE_REG_PERF_REGISTER: | |
60d53e2c | 1684 | return enable_trace_kprobe(event, NULL); |
2239291a | 1685 | case TRACE_REG_PERF_UNREGISTER: |
60d53e2c | 1686 | return disable_trace_kprobe(event, NULL); |
ceec0b6f JO |
1687 | case TRACE_REG_PERF_OPEN: |
1688 | case TRACE_REG_PERF_CLOSE: | |
489c75c3 JO |
1689 | case TRACE_REG_PERF_ADD: |
1690 | case TRACE_REG_PERF_DEL: | |
ceec0b6f | 1691 | return 0; |
2239291a SR |
1692 | #endif |
1693 | } | |
1694 | return 0; | |
1695 | } | |
50d78056 | 1696 | |
3da0f180 | 1697 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) |
50d78056 | 1698 | { |
c31ffb3f | 1699 | struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp); |
9802d865 | 1700 | int ret = 0; |
e08d1c65 | 1701 | |
a7636d9e | 1702 | raw_cpu_inc(*tk->nhit); |
48182bd2 | 1703 | |
747774d6 | 1704 | if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE)) |
c31ffb3f | 1705 | kprobe_trace_func(tk, regs); |
07b139c8 | 1706 | #ifdef CONFIG_PERF_EVENTS |
747774d6 | 1707 | if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE)) |
9802d865 | 1708 | ret = kprobe_perf_func(tk, regs); |
07b139c8 | 1709 | #endif |
9802d865 | 1710 | return ret; |
50d78056 | 1711 | } |
3da0f180 | 1712 | NOKPROBE_SYMBOL(kprobe_dispatcher); |
50d78056 | 1713 | |
3da0f180 MH |
1714 | static int |
1715 | kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) | |
50d78056 | 1716 | { |
c31ffb3f | 1717 | struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp); |
50d78056 | 1718 | |
a7636d9e | 1719 | raw_cpu_inc(*tk->nhit); |
48182bd2 | 1720 | |
747774d6 | 1721 | if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE)) |
c31ffb3f | 1722 | kretprobe_trace_func(tk, ri, regs); |
07b139c8 | 1723 | #ifdef CONFIG_PERF_EVENTS |
747774d6 | 1724 | if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE)) |
c31ffb3f | 1725 | kretprobe_perf_func(tk, ri, regs); |
07b139c8 | 1726 | #endif |
50d78056 MH |
1727 | return 0; /* We don't tweek kernel, so just return 0 */ |
1728 | } | |
3da0f180 | 1729 | NOKPROBE_SYMBOL(kretprobe_dispatcher); |
e08d1c65 | 1730 | |
a9a57763 SR |
1731 | static struct trace_event_functions kretprobe_funcs = { |
1732 | .trace = print_kretprobe_event | |
1733 | }; | |
1734 | ||
1735 | static struct trace_event_functions kprobe_funcs = { | |
1736 | .trace = print_kprobe_event | |
1737 | }; | |
1738 | ||
04ae87a5 PZ |
1739 | static struct trace_event_fields kretprobe_fields_array[] = { |
1740 | { .type = TRACE_FUNCTION_TYPE, | |
1741 | .define_fields = kretprobe_event_define_fields }, | |
1742 | {} | |
1743 | }; | |
1744 | ||
1745 | static struct trace_event_fields kprobe_fields_array[] = { | |
1746 | { .type = TRACE_FUNCTION_TYPE, | |
1747 | .define_fields = kprobe_event_define_fields }, | |
1748 | {} | |
1749 | }; | |
1750 | ||
e3dc9f89 | 1751 | static inline void init_trace_event_call(struct trace_kprobe *tk) |
413d37d1 | 1752 | { |
e3dc9f89 MH |
1753 | struct trace_event_call *call = trace_probe_event_call(&tk->tp); |
1754 | ||
c31ffb3f | 1755 | if (trace_kprobe_is_return(tk)) { |
80decc70 | 1756 | call->event.funcs = &kretprobe_funcs; |
04ae87a5 | 1757 | call->class->fields_array = kretprobe_fields_array; |
413d37d1 | 1758 | } else { |
80decc70 | 1759 | call->event.funcs = &kprobe_funcs; |
04ae87a5 | 1760 | call->class->fields_array = kprobe_fields_array; |
413d37d1 | 1761 | } |
e12f03d7 SL |
1762 | |
1763 | call->flags = TRACE_EVENT_FL_KPROBE; | |
1764 | call->class->reg = kprobe_register; | |
e12f03d7 SL |
1765 | } |
1766 | ||
1767 | static int register_kprobe_event(struct trace_kprobe *tk) | |
1768 | { | |
e3dc9f89 | 1769 | init_trace_event_call(tk); |
f730e0f2 | 1770 | |
46e5376d | 1771 | return trace_probe_register_event_call(&tk->tp); |
413d37d1 MH |
1772 | } |
1773 | ||
c31ffb3f | 1774 | static int unregister_kprobe_event(struct trace_kprobe *tk) |
413d37d1 | 1775 | { |
46e5376d | 1776 | return trace_probe_unregister_event_call(&tk->tp); |
413d37d1 MH |
1777 | } |
1778 | ||
e12f03d7 SL |
1779 | #ifdef CONFIG_PERF_EVENTS |
1780 | /* create a trace_kprobe, but don't add it to global lists */ | |
1781 | struct trace_event_call * | |
1782 | create_local_trace_kprobe(char *func, void *addr, unsigned long offs, | |
1783 | bool is_return) | |
1784 | { | |
1785 | struct trace_kprobe *tk; | |
1786 | int ret; | |
1787 | char *event; | |
1788 | ||
1789 | /* | |
6212dd29 | 1790 | * local trace_kprobes are not added to dyn_event, so they are never |
e12f03d7 SL |
1791 | * searched in find_trace_kprobe(). Therefore, there is no concern of |
1792 | * duplicated name here. | |
1793 | */ | |
1794 | event = func ? func : "DUMMY_EVENT"; | |
1795 | ||
1796 | tk = alloc_trace_kprobe(KPROBE_EVENT_SYSTEM, event, (void *)addr, func, | |
1797 | offs, 0 /* maxactive */, 0 /* nargs */, | |
1798 | is_return); | |
1799 | ||
1800 | if (IS_ERR(tk)) { | |
1801 | pr_info("Failed to allocate trace_probe.(%d)\n", | |
1802 | (int)PTR_ERR(tk)); | |
1803 | return ERR_CAST(tk); | |
1804 | } | |
1805 | ||
e3dc9f89 | 1806 | init_trace_event_call(tk); |
e12f03d7 | 1807 | |
0a46c854 | 1808 | if (traceprobe_set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) { |
e12f03d7 SL |
1809 | ret = -ENOMEM; |
1810 | goto error; | |
1811 | } | |
1812 | ||
1813 | ret = __register_trace_kprobe(tk); | |
f730e0f2 | 1814 | if (ret < 0) |
e12f03d7 SL |
1815 | goto error; |
1816 | ||
e3dc9f89 | 1817 | return trace_probe_event_call(&tk->tp); |
e12f03d7 SL |
1818 | error: |
1819 | free_trace_kprobe(tk); | |
1820 | return ERR_PTR(ret); | |
1821 | } | |
1822 | ||
1823 | void destroy_local_trace_kprobe(struct trace_event_call *event_call) | |
1824 | { | |
1825 | struct trace_kprobe *tk; | |
1826 | ||
60d53e2c MH |
1827 | tk = trace_kprobe_primary_from_call(event_call); |
1828 | if (unlikely(!tk)) | |
1829 | return; | |
e12f03d7 SL |
1830 | |
1831 | if (trace_probe_is_enabled(&tk->tp)) { | |
1832 | WARN_ON(1); | |
1833 | return; | |
1834 | } | |
1835 | ||
1836 | __unregister_trace_kprobe(tk); | |
0fc8c358 | 1837 | |
e12f03d7 SL |
1838 | free_trace_kprobe(tk); |
1839 | } | |
1840 | #endif /* CONFIG_PERF_EVENTS */ | |
1841 | ||
970988e1 MH |
1842 | static __init void enable_boot_kprobe_events(void) |
1843 | { | |
1844 | struct trace_array *tr = top_trace_array(); | |
1845 | struct trace_event_file *file; | |
1846 | struct trace_kprobe *tk; | |
1847 | struct dyn_event *pos; | |
1848 | ||
1849 | mutex_lock(&event_mutex); | |
1850 | for_each_trace_kprobe(tk, pos) { | |
1851 | list_for_each_entry(file, &tr->events, list) | |
e3dc9f89 | 1852 | if (file->event_call == trace_probe_event_call(&tk->tp)) |
970988e1 MH |
1853 | trace_event_enable_disable(file, 1, 0); |
1854 | } | |
1855 | mutex_unlock(&event_mutex); | |
1856 | } | |
1857 | ||
1858 | static __init void setup_boot_kprobe_events(void) | |
1859 | { | |
1860 | char *p, *cmd = kprobe_boot_events_buf; | |
1861 | int ret; | |
1862 | ||
1863 | strreplace(kprobe_boot_events_buf, ',', ' '); | |
1864 | ||
1865 | while (cmd && *cmd != '\0') { | |
1866 | p = strchr(cmd, ';'); | |
1867 | if (p) | |
1868 | *p++ = '\0'; | |
1869 | ||
1870 | ret = trace_run_command(cmd, create_or_delete_trace_kprobe); | |
1871 | if (ret) | |
1872 | pr_warn("Failed to add event(%d): %s\n", ret, cmd); | |
b6399cc7 SRV |
1873 | else |
1874 | kprobe_boot_events_enabled = true; | |
970988e1 MH |
1875 | |
1876 | cmd = p; | |
1877 | } | |
1878 | ||
1879 | enable_boot_kprobe_events(); | |
1880 | } | |
1881 | ||
d8d4c6d0 MH |
1882 | /* |
1883 | * Register dynevent at subsys_initcall. This allows kernel to setup kprobe | |
1884 | * events in fs_initcall without tracefs. | |
1885 | */ | |
1886 | static __init int init_kprobe_trace_early(void) | |
413d37d1 | 1887 | { |
6212dd29 MH |
1888 | int ret; |
1889 | ||
1890 | ret = dyn_event_register(&trace_kprobe_ops); | |
1891 | if (ret) | |
1892 | return ret; | |
413d37d1 | 1893 | |
c31ffb3f | 1894 | if (register_module_notifier(&trace_kprobe_module_nb)) |
61424318 MH |
1895 | return -EINVAL; |
1896 | ||
d8d4c6d0 MH |
1897 | return 0; |
1898 | } | |
1899 | subsys_initcall(init_kprobe_trace_early); | |
1900 | ||
1901 | /* Make a tracefs interface for controlling probe points */ | |
1902 | static __init int init_kprobe_trace(void) | |
1903 | { | |
1904 | struct dentry *d_tracer; | |
1905 | struct dentry *entry; | |
1906 | ||
413d37d1 | 1907 | d_tracer = tracing_init_dentry(); |
14a5ae40 | 1908 | if (IS_ERR(d_tracer)) |
413d37d1 MH |
1909 | return 0; |
1910 | ||
8434dc93 | 1911 | entry = tracefs_create_file("kprobe_events", 0644, d_tracer, |
413d37d1 MH |
1912 | NULL, &kprobe_events_ops); |
1913 | ||
cd7e7bd5 | 1914 | /* Event list interface */ |
413d37d1 | 1915 | if (!entry) |
a395d6a7 | 1916 | pr_warn("Could not create tracefs 'kprobe_events' entry\n"); |
cd7e7bd5 MH |
1917 | |
1918 | /* Profile interface */ | |
8434dc93 | 1919 | entry = tracefs_create_file("kprobe_profile", 0444, d_tracer, |
cd7e7bd5 MH |
1920 | NULL, &kprobe_profile_ops); |
1921 | ||
1922 | if (!entry) | |
a395d6a7 | 1923 | pr_warn("Could not create tracefs 'kprobe_profile' entry\n"); |
970988e1 MH |
1924 | |
1925 | setup_boot_kprobe_events(); | |
1926 | ||
413d37d1 MH |
1927 | return 0; |
1928 | } | |
1929 | fs_initcall(init_kprobe_trace); | |
1930 | ||
1931 | ||
1932 | #ifdef CONFIG_FTRACE_STARTUP_TEST | |
26a346f2 | 1933 | static __init struct trace_event_file * |
c31ffb3f | 1934 | find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr) |
41a7dd42 | 1935 | { |
7f1d2f82 | 1936 | struct trace_event_file *file; |
41a7dd42 MH |
1937 | |
1938 | list_for_each_entry(file, &tr->events, list) | |
e3dc9f89 | 1939 | if (file->event_call == trace_probe_event_call(&tk->tp)) |
41a7dd42 MH |
1940 | return file; |
1941 | ||
1942 | return NULL; | |
1943 | } | |
1944 | ||
3fe3d619 | 1945 | /* |
c31ffb3f | 1946 | * Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this |
3fe3d619 ON |
1947 | * stage, we can do this lockless. |
1948 | */ | |
413d37d1 MH |
1949 | static __init int kprobe_trace_self_tests_init(void) |
1950 | { | |
231e36f4 | 1951 | int ret, warn = 0; |
413d37d1 | 1952 | int (*target)(int, int, int, int, int, int); |
c31ffb3f | 1953 | struct trace_kprobe *tk; |
7f1d2f82 | 1954 | struct trace_event_file *file; |
413d37d1 | 1955 | |
748ec3a2 YY |
1956 | if (tracing_is_disabled()) |
1957 | return -ENODEV; | |
1958 | ||
b6399cc7 SRV |
1959 | if (kprobe_boot_events_enabled) { |
1960 | pr_info("Skipping kprobe tests due to kprobe_event on cmdline\n"); | |
1961 | return 0; | |
1962 | } | |
1963 | ||
413d37d1 MH |
1964 | target = kprobe_trace_selftest_target; |
1965 | ||
1966 | pr_info("Testing kprobe tracing: "); | |
1967 | ||
6212dd29 MH |
1968 | ret = trace_run_command("p:testprobe kprobe_trace_selftest_target $stack $stack0 +0($stack)", |
1969 | create_or_delete_trace_kprobe); | |
231e36f4 | 1970 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1971 | pr_warn("error on probing function entry.\n"); |
231e36f4 MH |
1972 | warn++; |
1973 | } else { | |
1974 | /* Enable trace point */ | |
c31ffb3f NK |
1975 | tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); |
1976 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1977 | pr_warn("error on getting new probe.\n"); |
231e36f4 | 1978 | warn++; |
41a7dd42 | 1979 | } else { |
c31ffb3f | 1980 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
1981 | if (WARN_ON_ONCE(file == NULL)) { |
1982 | pr_warn("error on getting probe file.\n"); | |
1983 | warn++; | |
1984 | } else | |
60d53e2c MH |
1985 | enable_trace_kprobe( |
1986 | trace_probe_event_call(&tk->tp), file); | |
41a7dd42 | 1987 | } |
231e36f4 | 1988 | } |
413d37d1 | 1989 | |
6212dd29 MH |
1990 | ret = trace_run_command("r:testprobe2 kprobe_trace_selftest_target $retval", |
1991 | create_or_delete_trace_kprobe); | |
231e36f4 | 1992 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1993 | pr_warn("error on probing function return.\n"); |
231e36f4 MH |
1994 | warn++; |
1995 | } else { | |
1996 | /* Enable trace point */ | |
c31ffb3f NK |
1997 | tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); |
1998 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1999 | pr_warn("error on getting 2nd new probe.\n"); |
231e36f4 | 2000 | warn++; |
41a7dd42 | 2001 | } else { |
c31ffb3f | 2002 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
2003 | if (WARN_ON_ONCE(file == NULL)) { |
2004 | pr_warn("error on getting probe file.\n"); | |
2005 | warn++; | |
2006 | } else | |
60d53e2c MH |
2007 | enable_trace_kprobe( |
2008 | trace_probe_event_call(&tk->tp), file); | |
41a7dd42 | 2009 | } |
231e36f4 MH |
2010 | } |
2011 | ||
2012 | if (warn) | |
2013 | goto end; | |
413d37d1 MH |
2014 | |
2015 | ret = target(1, 2, 3, 4, 5, 6); | |
2016 | ||
d4d7ccc8 MN |
2017 | /* |
2018 | * Not expecting an error here, the check is only to prevent the | |
2019 | * optimizer from removing the call to target() as otherwise there | |
2020 | * are no side-effects and the call is never performed. | |
2021 | */ | |
2022 | if (ret != 21) | |
2023 | warn++; | |
2024 | ||
02ca1521 | 2025 | /* Disable trace points before removing it */ |
c31ffb3f NK |
2026 | tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); |
2027 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 2028 | pr_warn("error on getting test probe.\n"); |
02ca1521 | 2029 | warn++; |
41a7dd42 | 2030 | } else { |
d4d7ccc8 MN |
2031 | if (trace_kprobe_nhit(tk) != 1) { |
2032 | pr_warn("incorrect number of testprobe hits\n"); | |
2033 | warn++; | |
2034 | } | |
2035 | ||
c31ffb3f | 2036 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
2037 | if (WARN_ON_ONCE(file == NULL)) { |
2038 | pr_warn("error on getting probe file.\n"); | |
2039 | warn++; | |
2040 | } else | |
60d53e2c MH |
2041 | disable_trace_kprobe( |
2042 | trace_probe_event_call(&tk->tp), file); | |
41a7dd42 | 2043 | } |
02ca1521 | 2044 | |
c31ffb3f NK |
2045 | tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); |
2046 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 2047 | pr_warn("error on getting 2nd test probe.\n"); |
02ca1521 | 2048 | warn++; |
41a7dd42 | 2049 | } else { |
d4d7ccc8 MN |
2050 | if (trace_kprobe_nhit(tk) != 1) { |
2051 | pr_warn("incorrect number of testprobe2 hits\n"); | |
2052 | warn++; | |
2053 | } | |
2054 | ||
c31ffb3f | 2055 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
2056 | if (WARN_ON_ONCE(file == NULL)) { |
2057 | pr_warn("error on getting probe file.\n"); | |
2058 | warn++; | |
2059 | } else | |
60d53e2c MH |
2060 | disable_trace_kprobe( |
2061 | trace_probe_event_call(&tk->tp), file); | |
41a7dd42 | 2062 | } |
02ca1521 | 2063 | |
6212dd29 | 2064 | ret = trace_run_command("-:testprobe", create_or_delete_trace_kprobe); |
231e36f4 | 2065 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 2066 | pr_warn("error on deleting a probe.\n"); |
231e36f4 MH |
2067 | warn++; |
2068 | } | |
2069 | ||
6212dd29 | 2070 | ret = trace_run_command("-:testprobe2", create_or_delete_trace_kprobe); |
231e36f4 | 2071 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 2072 | pr_warn("error on deleting a probe.\n"); |
231e36f4 MH |
2073 | warn++; |
2074 | } | |
413d37d1 | 2075 | |
231e36f4 | 2076 | end: |
6212dd29 MH |
2077 | ret = dyn_events_release_all(&trace_kprobe_ops); |
2078 | if (WARN_ON_ONCE(ret)) { | |
2079 | pr_warn("error on cleaning up probes.\n"); | |
2080 | warn++; | |
2081 | } | |
30e7d894 TG |
2082 | /* |
2083 | * Wait for the optimizer work to finish. Otherwise it might fiddle | |
2084 | * with probes in already freed __init text. | |
2085 | */ | |
2086 | wait_for_kprobe_optimizer(); | |
231e36f4 MH |
2087 | if (warn) |
2088 | pr_cont("NG: Some tests are failed. Please check them.\n"); | |
2089 | else | |
2090 | pr_cont("OK\n"); | |
413d37d1 MH |
2091 | return 0; |
2092 | } | |
2093 | ||
2094 | late_initcall(kprobe_trace_self_tests_init); | |
2095 | ||
2096 | #endif |