Commit | Line | Data |
---|---|---|
259b6cb3 MD |
1 | /* |
2 | * lttng-syscalls.c | |
3 | * | |
2faf7d1b | 4 | * LTTng syscall probes. |
259b6cb3 | 5 | * |
886d51a3 MD |
6 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
7 | * | |
8 | * This library is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU Lesser General Public | |
10 | * License as published by the Free Software Foundation; only | |
11 | * version 2.1 of the License. | |
12 | * | |
13 | * This library is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | * Lesser General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU Lesser General Public | |
19 | * License along with this library; if not, write to the Free Software | |
20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
259b6cb3 MD |
21 | */ |
22 | ||
23 | #include <linux/module.h> | |
24 | #include <linux/slab.h> | |
6333ace3 | 25 | #include <linux/compat.h> |
259b6cb3 MD |
26 | #include <asm/ptrace.h> |
27 | #include <asm/syscall.h> | |
28 | ||
3a523f5b | 29 | #include "wrapper/tracepoint.h" |
a90917c3 | 30 | #include "lttng-events.h" |
259b6cb3 | 31 | |
6333ace3 | 32 | #ifndef CONFIG_COMPAT |
bfa949bf MD |
33 | # ifndef is_compat_task |
34 | # define is_compat_task() (0) | |
35 | # endif | |
6333ace3 MD |
36 | #endif |
37 | ||
a93244f8 | 38 | static |
2faf7d1b | 39 | void syscall_entry_probe(void *__data, struct pt_regs *regs, long id); |
259b6cb3 | 40 | |
3a523f5b MD |
41 | /* |
42 | * Forward declarations for old kernels. | |
43 | */ | |
44 | struct mmsghdr; | |
45 | struct rlimit64; | |
46 | struct oldold_utsname; | |
47 | struct old_utsname; | |
48 | struct sel_arg_struct; | |
49 | struct mmap_arg_struct; | |
50 | ||
f7bdf4db MD |
51 | /* |
52 | * Take care of NOARGS not supported by mainline. | |
53 | */ | |
54 | #define DECLARE_EVENT_CLASS_NOARGS(name, tstruct, assign, print) | |
55 | #define DEFINE_EVENT_NOARGS(template, name) | |
56 | #define TRACE_EVENT_NOARGS(name, struct, assign, print) | |
57 | ||
259b6cb3 MD |
58 | /* |
59 | * Create LTTng tracepoint probes. | |
60 | */ | |
61 | #define LTTNG_PACKAGE_BUILD | |
62 | #define CREATE_TRACE_POINTS | |
2655f9ad | 63 | #define TP_MODULE_NOINIT |
2f804c0a | 64 | #define TRACE_INCLUDE_PATH ../instrumentation/syscalls/headers |
259b6cb3 | 65 | |
a93244f8 MD |
66 | #define PARAMS(args...) args |
67 | ||
259b6cb3 | 68 | /* Hijack probe callback for system calls */ |
a93244f8 | 69 | #undef TP_PROBE_CB |
259b6cb3 | 70 | #define TP_PROBE_CB(_template) &syscall_entry_probe |
a93244f8 MD |
71 | #define SC_TRACE_EVENT(_name, _proto, _args, _struct, _assign, _printk) \ |
72 | TRACE_EVENT(_name, PARAMS(_proto), PARAMS(_args),\ | |
73 | PARAMS(_struct), PARAMS(_assign), PARAMS(_printk)) | |
74 | #define SC_DECLARE_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \ | |
75 | DECLARE_EVENT_CLASS_NOARGS(_name, PARAMS(_struct), PARAMS(_assign),\ | |
76 | PARAMS(_printk)) | |
77 | #define SC_DEFINE_EVENT_NOARGS(_template, _name) \ | |
78 | DEFINE_EVENT_NOARGS(_template, _name) | |
79 | #undef TRACE_SYSTEM | |
80 | #define TRACE_SYSTEM syscalls_integers | |
177b3692 | 81 | #include "instrumentation/syscalls/headers/syscalls_integers.h" |
a93244f8 MD |
82 | #undef TRACE_SYSTEM |
83 | #define TRACE_SYSTEM syscalls_pointers | |
177b3692 | 84 | #include "instrumentation/syscalls/headers/syscalls_pointers.h" |
a93244f8 MD |
85 | #undef TRACE_SYSTEM |
86 | #undef SC_TRACE_EVENT | |
87 | #undef SC_DECLARE_EVENT_CLASS_NOARGS | |
88 | #undef SC_DEFINE_EVENT_NOARGS | |
2f804c0a | 89 | |
a93244f8 | 90 | #define TRACE_SYSTEM syscalls_unknown |
63728b02 | 91 | #include "instrumentation/syscalls/headers/syscalls_unknown.h" |
a93244f8 MD |
92 | #undef TRACE_SYSTEM |
93 | ||
94 | /* For compat syscalls */ | |
95 | #undef _TRACE_SYSCALLS_integers_H | |
96 | #undef _TRACE_SYSCALLS_pointers_H | |
97 | ||
98 | /* Hijack probe callback for system calls */ | |
99 | #undef TP_PROBE_CB | |
100 | #define TP_PROBE_CB(_template) &syscall_entry_probe | |
101 | #define SC_TRACE_EVENT(_name, _proto, _args, _struct, _assign, _printk) \ | |
102 | TRACE_EVENT(compat_##_name, PARAMS(_proto), PARAMS(_args), \ | |
103 | PARAMS(_struct), PARAMS(_assign), \ | |
104 | PARAMS(_printk)) | |
105 | #define SC_DECLARE_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \ | |
106 | DECLARE_EVENT_CLASS_NOARGS(compat_##_name, PARAMS(_struct), \ | |
107 | PARAMS(_assign), PARAMS(_printk)) | |
108 | #define SC_DEFINE_EVENT_NOARGS(_template, _name) \ | |
109 | DEFINE_EVENT_NOARGS(compat_##_template, compat_##_name) | |
110 | #define TRACE_SYSTEM compat_syscalls_integers | |
111 | #include "instrumentation/syscalls/headers/compat_syscalls_integers.h" | |
112 | #undef TRACE_SYSTEM | |
113 | #define TRACE_SYSTEM compat_syscalls_pointers | |
114 | #include "instrumentation/syscalls/headers/compat_syscalls_pointers.h" | |
115 | #undef TRACE_SYSTEM | |
116 | #undef SC_TRACE_EVENT | |
117 | #undef SC_DECLARE_EVENT_CLASS_NOARGS | |
118 | #undef SC_DEFINE_EVENT_NOARGS | |
119 | #undef TP_PROBE_CB | |
259b6cb3 | 120 | |
2655f9ad | 121 | #undef TP_MODULE_NOINIT |
259b6cb3 MD |
122 | #undef LTTNG_PACKAGE_BUILD |
123 | #undef CREATE_TRACE_POINTS | |
124 | ||
a93244f8 MD |
125 | struct trace_syscall_entry { |
126 | void *func; | |
127 | const struct lttng_event_desc *desc; | |
128 | const struct lttng_event_field *fields; | |
129 | unsigned int nrargs; | |
130 | }; | |
131 | ||
132 | #define CREATE_SYSCALL_TABLE | |
133 | ||
259b6cb3 | 134 | #undef TRACE_SYSCALL_TABLE |
f7bdf4db | 135 | #define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \ |
259b6cb3 | 136 | [ _nr ] = { \ |
f7bdf4db | 137 | .func = __event_probe__##_template, \ |
259b6cb3 | 138 | .nrargs = (_nrargs), \ |
f7bdf4db MD |
139 | .fields = __event_fields___##_template, \ |
140 | .desc = &__event_desc___##_name, \ | |
259b6cb3 MD |
141 | }, |
142 | ||
49c50022 | 143 | static const struct trace_syscall_entry sc_table[] = { |
177b3692 MD |
144 | #include "instrumentation/syscalls/headers/syscalls_integers.h" |
145 | #include "instrumentation/syscalls/headers/syscalls_pointers.h" | |
259b6cb3 MD |
146 | }; |
147 | ||
a93244f8 MD |
148 | #undef TRACE_SYSCALL_TABLE |
149 | #define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \ | |
150 | [ _nr ] = { \ | |
151 | .func = __event_probe__##compat_##_template, \ | |
152 | .nrargs = (_nrargs), \ | |
153 | .fields = __event_fields___##compat_##_template,\ | |
154 | .desc = &__event_desc___##compat_##_name, \ | |
155 | }, | |
156 | ||
157 | /* Create compatibility syscall table */ | |
158 | const struct trace_syscall_entry compat_sc_table[] = { | |
159 | #include "instrumentation/syscalls/headers/compat_syscalls_integers.h" | |
160 | #include "instrumentation/syscalls/headers/compat_syscalls_pointers.h" | |
161 | }; | |
259b6cb3 | 162 | |
a93244f8 | 163 | #undef CREATE_SYSCALL_TABLE |
2faf7d1b | 164 | |
a90917c3 | 165 | static void syscall_entry_unknown(struct lttng_event *event, |
f405cfce MD |
166 | struct pt_regs *regs, unsigned int id) |
167 | { | |
168 | unsigned long args[UNKNOWN_SYSCALL_NRARGS]; | |
f405cfce | 169 | |
f405cfce | 170 | syscall_get_arguments(current, regs, 0, UNKNOWN_SYSCALL_NRARGS, args); |
a93244f8 MD |
171 | if (unlikely(is_compat_task())) |
172 | __event_probe__compat_sys_unknown(event, id, args); | |
173 | else | |
174 | __event_probe__sys_unknown(event, id, args); | |
f405cfce MD |
175 | } |
176 | ||
2faf7d1b | 177 | void syscall_entry_probe(void *__data, struct pt_regs *regs, long id) |
259b6cb3 | 178 | { |
a90917c3 MD |
179 | struct lttng_channel *chan = __data; |
180 | struct lttng_event *event, *unknown_event; | |
49c50022 MD |
181 | const struct trace_syscall_entry *table, *entry; |
182 | size_t table_len; | |
259b6cb3 | 183 | |
b76dc1a0 | 184 | if (unlikely(is_compat_task())) { |
49c50022 | 185 | table = compat_sc_table; |
a93244f8 | 186 | table_len = ARRAY_SIZE(compat_sc_table); |
49c50022 MD |
187 | unknown_event = chan->sc_compat_unknown; |
188 | } else { | |
189 | table = sc_table; | |
190 | table_len = ARRAY_SIZE(sc_table); | |
191 | unknown_event = chan->sc_unknown; | |
b76dc1a0 | 192 | } |
49c50022 MD |
193 | if (unlikely(id >= table_len)) { |
194 | syscall_entry_unknown(unknown_event, regs, id); | |
259b6cb3 | 195 | return; |
f405cfce | 196 | } |
49c50022 MD |
197 | if (unlikely(is_compat_task())) |
198 | event = chan->compat_sc_table[id]; | |
199 | else | |
200 | event = chan->sc_table[id]; | |
f405cfce | 201 | if (unlikely(!event)) { |
49c50022 | 202 | syscall_entry_unknown(unknown_event, regs, id); |
f405cfce MD |
203 | return; |
204 | } | |
49c50022 | 205 | entry = &table[id]; |
f405cfce | 206 | WARN_ON_ONCE(!entry); |
259b6cb3 MD |
207 | |
208 | switch (entry->nrargs) { | |
209 | case 0: | |
210 | { | |
211 | void (*fptr)(void *__data) = entry->func; | |
212 | ||
213 | fptr(event); | |
214 | break; | |
215 | } | |
216 | case 1: | |
217 | { | |
218 | void (*fptr)(void *__data, unsigned long arg0) = entry->func; | |
219 | unsigned long args[1]; | |
220 | ||
221 | syscall_get_arguments(current, regs, 0, entry->nrargs, args); | |
222 | fptr(event, args[0]); | |
223 | break; | |
224 | } | |
225 | case 2: | |
226 | { | |
227 | void (*fptr)(void *__data, | |
228 | unsigned long arg0, | |
229 | unsigned long arg1) = entry->func; | |
230 | unsigned long args[2]; | |
231 | ||
232 | syscall_get_arguments(current, regs, 0, entry->nrargs, args); | |
233 | fptr(event, args[0], args[1]); | |
234 | break; | |
235 | } | |
236 | case 3: | |
237 | { | |
238 | void (*fptr)(void *__data, | |
239 | unsigned long arg0, | |
240 | unsigned long arg1, | |
241 | unsigned long arg2) = entry->func; | |
242 | unsigned long args[3]; | |
243 | ||
244 | syscall_get_arguments(current, regs, 0, entry->nrargs, args); | |
245 | fptr(event, args[0], args[1], args[2]); | |
246 | break; | |
247 | } | |
248 | case 4: | |
249 | { | |
250 | void (*fptr)(void *__data, | |
251 | unsigned long arg0, | |
252 | unsigned long arg1, | |
253 | unsigned long arg2, | |
254 | unsigned long arg3) = entry->func; | |
255 | unsigned long args[4]; | |
256 | ||
257 | syscall_get_arguments(current, regs, 0, entry->nrargs, args); | |
258 | fptr(event, args[0], args[1], args[2], args[3]); | |
259 | break; | |
260 | } | |
261 | case 5: | |
262 | { | |
263 | void (*fptr)(void *__data, | |
264 | unsigned long arg0, | |
265 | unsigned long arg1, | |
266 | unsigned long arg2, | |
267 | unsigned long arg3, | |
268 | unsigned long arg4) = entry->func; | |
269 | unsigned long args[5]; | |
270 | ||
271 | syscall_get_arguments(current, regs, 0, entry->nrargs, args); | |
272 | fptr(event, args[0], args[1], args[2], args[3], args[4]); | |
273 | break; | |
274 | } | |
275 | case 6: | |
276 | { | |
277 | void (*fptr)(void *__data, | |
278 | unsigned long arg0, | |
279 | unsigned long arg1, | |
280 | unsigned long arg2, | |
281 | unsigned long arg3, | |
282 | unsigned long arg4, | |
283 | unsigned long arg5) = entry->func; | |
284 | unsigned long args[6]; | |
285 | ||
286 | syscall_get_arguments(current, regs, 0, entry->nrargs, args); | |
287 | fptr(event, args[0], args[1], args[2], | |
288 | args[3], args[4], args[5]); | |
289 | break; | |
290 | } | |
291 | default: | |
292 | break; | |
293 | } | |
294 | } | |
295 | ||
2a0c4816 | 296 | /* noinline to diminish caller stack size */ |
49c50022 MD |
297 | static |
298 | int fill_table(const struct trace_syscall_entry *table, size_t table_len, | |
a90917c3 | 299 | struct lttng_event **chan_table, struct lttng_channel *chan, void *filter) |
259b6cb3 | 300 | { |
2a0c4816 | 301 | const struct lttng_event_desc *desc; |
259b6cb3 | 302 | unsigned int i; |
49c50022 MD |
303 | |
304 | /* Allocate events for each syscall, insert into table */ | |
305 | for (i = 0; i < table_len; i++) { | |
306 | struct lttng_kernel_event ev; | |
2a0c4816 | 307 | desc = table[i].desc; |
49c50022 MD |
308 | |
309 | if (!desc) { | |
310 | /* Unknown syscall */ | |
311 | continue; | |
312 | } | |
313 | /* | |
314 | * Skip those already populated by previous failed | |
315 | * register for this channel. | |
316 | */ | |
317 | if (chan_table[i]) | |
318 | continue; | |
319 | memset(&ev, 0, sizeof(ev)); | |
f8695253 MD |
320 | strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN); |
321 | ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0'; | |
49c50022 | 322 | ev.instrumentation = LTTNG_KERNEL_NOOP; |
a90917c3 | 323 | chan_table[i] = lttng_event_create(chan, &ev, filter, |
49c50022 MD |
324 | desc); |
325 | if (!chan_table[i]) { | |
326 | /* | |
327 | * If something goes wrong in event registration | |
328 | * after the first one, we have no choice but to | |
329 | * leave the previous events in there, until | |
330 | * deleted by session teardown. | |
331 | */ | |
332 | return -EINVAL; | |
333 | } | |
334 | } | |
335 | return 0; | |
336 | } | |
337 | ||
a90917c3 | 338 | int lttng_syscalls_register(struct lttng_channel *chan, void *filter) |
49c50022 | 339 | { |
2a0c4816 | 340 | struct lttng_kernel_event ev; |
259b6cb3 MD |
341 | int ret; |
342 | ||
343 | wrapper_vmalloc_sync_all(); | |
259b6cb3 MD |
344 | |
345 | if (!chan->sc_table) { | |
346 | /* create syscall table mapping syscall to events */ | |
a90917c3 | 347 | chan->sc_table = kzalloc(sizeof(struct lttng_event *) |
259b6cb3 MD |
348 | * ARRAY_SIZE(sc_table), GFP_KERNEL); |
349 | if (!chan->sc_table) | |
350 | return -ENOMEM; | |
351 | } | |
352 | ||
49c50022 MD |
353 | #ifdef CONFIG_COMPAT |
354 | if (!chan->compat_sc_table) { | |
355 | /* create syscall table mapping compat syscall to events */ | |
a90917c3 | 356 | chan->compat_sc_table = kzalloc(sizeof(struct lttng_event *) |
a93244f8 | 357 | * ARRAY_SIZE(compat_sc_table), GFP_KERNEL); |
49c50022 MD |
358 | if (!chan->compat_sc_table) |
359 | return -ENOMEM; | |
360 | } | |
361 | #endif | |
f405cfce | 362 | if (!chan->sc_unknown) { |
f405cfce MD |
363 | const struct lttng_event_desc *desc = |
364 | &__event_desc___sys_unknown; | |
2f804c0a | 365 | |
f405cfce | 366 | memset(&ev, 0, sizeof(ev)); |
f8695253 MD |
367 | strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN); |
368 | ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0'; | |
f405cfce | 369 | ev.instrumentation = LTTNG_KERNEL_NOOP; |
a90917c3 | 370 | chan->sc_unknown = lttng_event_create(chan, &ev, filter, |
f405cfce MD |
371 | desc); |
372 | if (!chan->sc_unknown) { | |
373 | return -EINVAL; | |
374 | } | |
375 | } | |
376 | ||
b76dc1a0 | 377 | if (!chan->sc_compat_unknown) { |
b76dc1a0 MD |
378 | const struct lttng_event_desc *desc = |
379 | &__event_desc___compat_sys_unknown; | |
380 | ||
381 | memset(&ev, 0, sizeof(ev)); | |
f8695253 MD |
382 | strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN); |
383 | ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0'; | |
b76dc1a0 | 384 | ev.instrumentation = LTTNG_KERNEL_NOOP; |
a90917c3 | 385 | chan->sc_compat_unknown = lttng_event_create(chan, &ev, filter, |
b76dc1a0 MD |
386 | desc); |
387 | if (!chan->sc_compat_unknown) { | |
388 | return -EINVAL; | |
389 | } | |
390 | } | |
391 | ||
2f804c0a | 392 | if (!chan->sc_exit) { |
2f804c0a MD |
393 | const struct lttng_event_desc *desc = |
394 | &__event_desc___exit_syscall; | |
395 | ||
396 | memset(&ev, 0, sizeof(ev)); | |
f8695253 MD |
397 | strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN); |
398 | ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0'; | |
2f804c0a | 399 | ev.instrumentation = LTTNG_KERNEL_NOOP; |
a90917c3 | 400 | chan->sc_exit = lttng_event_create(chan, &ev, filter, |
2f804c0a MD |
401 | desc); |
402 | if (!chan->sc_exit) { | |
403 | return -EINVAL; | |
404 | } | |
405 | } | |
406 | ||
49c50022 MD |
407 | ret = fill_table(sc_table, ARRAY_SIZE(sc_table), |
408 | chan->sc_table, chan, filter); | |
409 | if (ret) | |
410 | return ret; | |
411 | #ifdef CONFIG_COMPAT | |
a93244f8 | 412 | ret = fill_table(compat_sc_table, ARRAY_SIZE(compat_sc_table), |
49c50022 MD |
413 | chan->compat_sc_table, chan, filter); |
414 | if (ret) | |
415 | return ret; | |
416 | #endif | |
3a523f5b | 417 | ret = kabi_2635_tracepoint_probe_register("sys_enter", |
259b6cb3 | 418 | (void *) syscall_entry_probe, chan); |
63728b02 MD |
419 | if (ret) |
420 | return ret; | |
421 | /* | |
422 | * We change the name of sys_exit tracepoint due to namespace | |
423 | * conflict with sys_exit syscall entry. | |
424 | */ | |
3a523f5b | 425 | ret = kabi_2635_tracepoint_probe_register("sys_exit", |
2c01ec07 | 426 | (void *) __event_probe__exit_syscall, |
2f804c0a | 427 | chan->sc_exit); |
63728b02 | 428 | if (ret) { |
3a523f5b | 429 | WARN_ON_ONCE(kabi_2635_tracepoint_probe_unregister("sys_enter", |
63728b02 MD |
430 | (void *) syscall_entry_probe, chan)); |
431 | } | |
259b6cb3 MD |
432 | return ret; |
433 | } | |
434 | ||
435 | /* | |
436 | * Only called at session destruction. | |
437 | */ | |
a90917c3 | 438 | int lttng_syscalls_unregister(struct lttng_channel *chan) |
259b6cb3 MD |
439 | { |
440 | int ret; | |
441 | ||
442 | if (!chan->sc_table) | |
443 | return 0; | |
3a523f5b | 444 | ret = kabi_2635_tracepoint_probe_unregister("sys_exit", |
2c01ec07 | 445 | (void *) __event_probe__exit_syscall, |
2f804c0a | 446 | chan->sc_exit); |
63728b02 MD |
447 | if (ret) |
448 | return ret; | |
3a523f5b | 449 | ret = kabi_2635_tracepoint_probe_unregister("sys_enter", |
259b6cb3 MD |
450 | (void *) syscall_entry_probe, chan); |
451 | if (ret) | |
452 | return ret; | |
a90917c3 | 453 | /* lttng_event destroy will be performed by lttng_session_destroy() */ |
259b6cb3 | 454 | kfree(chan->sc_table); |
49c50022 MD |
455 | #ifdef CONFIG_COMPAT |
456 | kfree(chan->compat_sc_table); | |
457 | #endif | |
259b6cb3 MD |
458 | return 0; |
459 | } |