| 1 | /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only) |
| 2 | * |
| 3 | * lttng-syscalls.c |
| 4 | * |
| 5 | * LTTng syscall probes. |
| 6 | * |
| 7 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 8 | */ |
| 9 | |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/slab.h> |
| 12 | #include <linux/compat.h> |
| 13 | #include <linux/err.h> |
| 14 | #include <linux/bitmap.h> |
| 15 | #include <linux/in.h> |
| 16 | #include <linux/in6.h> |
| 17 | #include <linux/seq_file.h> |
| 18 | #include <linux/stringify.h> |
| 19 | #include <linux/file.h> |
| 20 | #include <linux/anon_inodes.h> |
| 21 | #include <linux/fcntl.h> |
| 22 | #include <linux/mman.h> |
| 23 | #include <asm/ptrace.h> |
| 24 | #include <asm/syscall.h> |
| 25 | |
| 26 | #include <lttng/bitfield.h> |
| 27 | #include <wrapper/tracepoint.h> |
| 28 | #include <wrapper/file.h> |
| 29 | #include <wrapper/rcu.h> |
| 30 | #include <wrapper/syscall.h> |
| 31 | #include <lttng/events.h> |
| 32 | #include <lttng/events-internal.h> |
| 33 | #include <lttng/utils.h> |
| 34 | |
| 35 | #include "lttng-syscalls.h" |
| 36 | |
| 37 | #ifndef CONFIG_COMPAT |
| 38 | # ifndef is_compat_task |
| 39 | # define is_compat_task() (0) |
| 40 | # endif |
| 41 | #endif |
| 42 | |
| 43 | /* in_compat_syscall appears in kernel 4.6. */ |
| 44 | #ifndef in_compat_syscall |
| 45 | #define in_compat_syscall() is_compat_task() |
| 46 | #endif |
| 47 | |
| 48 | enum sc_type { |
| 49 | SC_TYPE_ENTRY, |
| 50 | SC_TYPE_EXIT, |
| 51 | SC_TYPE_COMPAT_ENTRY, |
| 52 | SC_TYPE_COMPAT_EXIT, |
| 53 | }; |
| 54 | |
| 55 | #define SYSCALL_ENTRY_TOK syscall_entry_ |
| 56 | #define COMPAT_SYSCALL_ENTRY_TOK compat_syscall_entry_ |
| 57 | #define SYSCALL_EXIT_TOK syscall_exit_ |
| 58 | #define COMPAT_SYSCALL_EXIT_TOK compat_syscall_exit_ |
| 59 | |
| 60 | #define SYSCALL_ENTRY_STR __stringify(SYSCALL_ENTRY_TOK) |
| 61 | #define COMPAT_SYSCALL_ENTRY_STR __stringify(COMPAT_SYSCALL_ENTRY_TOK) |
| 62 | #define SYSCALL_EXIT_STR __stringify(SYSCALL_EXIT_TOK) |
| 63 | #define COMPAT_SYSCALL_EXIT_STR __stringify(COMPAT_SYSCALL_EXIT_TOK) |
| 64 | |
| 65 | void syscall_entry_event_probe(void *__data, struct pt_regs *regs, long id); |
| 66 | void syscall_exit_event_probe(void *__data, struct pt_regs *regs, long ret); |
| 67 | |
| 68 | /* |
| 69 | * Forward declarations for old kernels. |
| 70 | */ |
| 71 | struct mmsghdr; |
| 72 | struct rlimit64; |
| 73 | struct oldold_utsname; |
| 74 | struct old_utsname; |
| 75 | struct sel_arg_struct; |
| 76 | struct mmap_arg_struct; |
| 77 | struct file_handle; |
| 78 | struct user_msghdr; |
| 79 | |
| 80 | /* |
| 81 | * Forward declaration for kernels >= 5.6 |
| 82 | */ |
| 83 | struct timex; |
| 84 | struct timeval; |
| 85 | struct itimerval; |
| 86 | struct itimerspec; |
| 87 | |
| 88 | #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,6,0)) |
| 89 | typedef __kernel_old_time_t time_t; |
| 90 | #endif |
| 91 | |
| 92 | #ifdef IA32_NR_syscalls |
| 93 | #define NR_compat_syscalls IA32_NR_syscalls |
| 94 | #else |
| 95 | #define NR_compat_syscalls NR_syscalls |
| 96 | #endif |
| 97 | |
| 98 | /* |
| 99 | * Create LTTng tracepoint probes. |
| 100 | */ |
| 101 | #define LTTNG_PACKAGE_BUILD |
| 102 | #define CREATE_TRACE_POINTS |
| 103 | #define TP_MODULE_NOINIT |
| 104 | #define TRACE_INCLUDE_PATH instrumentation/syscalls/headers |
| 105 | |
| 106 | #define PARAMS(args...) args |
| 107 | |
| 108 | /* Handle unknown syscalls */ |
| 109 | #undef TRACE_SYSTEM |
| 110 | #define TRACE_SYSTEM syscalls_unknown |
| 111 | #include <instrumentation/syscalls/headers/syscalls_unknown.h> |
| 112 | #undef TRACE_SYSTEM |
| 113 | |
| 114 | #undef TP_PROBE_CB |
| 115 | |
| 116 | extern const struct trace_syscall_table sc_table; |
| 117 | extern const struct trace_syscall_table compat_sc_table; |
| 118 | |
| 119 | /* Event syscall exit table */ |
| 120 | extern const struct trace_syscall_table sc_exit_table; |
| 121 | extern const struct trace_syscall_table compat_sc_exit_table; |
| 122 | |
| 123 | |
| 124 | #undef SC_EXIT |
| 125 | |
| 126 | #undef CREATE_SYSCALL_TABLE |
| 127 | |
| 128 | struct lttng_syscall_filter { |
| 129 | DECLARE_BITMAP(sc_entry, NR_syscalls); |
| 130 | DECLARE_BITMAP(sc_exit, NR_syscalls); |
| 131 | DECLARE_BITMAP(sc_compat_entry, NR_compat_syscalls); |
| 132 | DECLARE_BITMAP(sc_compat_exit, NR_compat_syscalls); |
| 133 | }; |
| 134 | |
| 135 | static |
| 136 | int lttng_syscalls_create_matching_event_notifiers(struct lttng_event_enabler_common *event_enabler); |
| 137 | |
| 138 | static void syscall_entry_event_unknown(struct hlist_head *unknown_action_list_head, |
| 139 | struct pt_regs *regs, long id) |
| 140 | { |
| 141 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 142 | struct lttng_kernel_event_common_private *event_priv; |
| 143 | |
| 144 | lttng_syscall_get_arguments(current, regs, args); |
| 145 | lttng_hlist_for_each_entry_rcu(event_priv, unknown_action_list_head, u.syscall.node) { |
| 146 | if (unlikely(in_compat_syscall())) |
| 147 | __event_probe__compat_syscall_entry_unknown(event_priv->pub, id, args); |
| 148 | else |
| 149 | __event_probe__syscall_entry_unknown(event_priv->pub, id, args); |
| 150 | } |
| 151 | } |
| 152 | |
| 153 | static __always_inline |
| 154 | void syscall_entry_event_call_func(struct hlist_head *action_list, |
| 155 | void *func, unsigned int nrargs, |
| 156 | struct pt_regs *regs) |
| 157 | { |
| 158 | struct lttng_kernel_event_common_private *event_priv; |
| 159 | |
| 160 | switch (nrargs) { |
| 161 | case 0: |
| 162 | { |
| 163 | void (*fptr)(void *__data) = func; |
| 164 | |
| 165 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 166 | fptr(event_priv->pub); |
| 167 | break; |
| 168 | } |
| 169 | case 1: |
| 170 | { |
| 171 | void (*fptr)(void *__data, unsigned long arg0) = func; |
| 172 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 173 | |
| 174 | lttng_syscall_get_arguments(current, regs, args); |
| 175 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 176 | fptr(event_priv->pub, args[0]); |
| 177 | break; |
| 178 | } |
| 179 | case 2: |
| 180 | { |
| 181 | void (*fptr)(void *__data, |
| 182 | unsigned long arg0, |
| 183 | unsigned long arg1) = func; |
| 184 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 185 | |
| 186 | lttng_syscall_get_arguments(current, regs, args); |
| 187 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 188 | fptr(event_priv->pub, args[0], args[1]); |
| 189 | break; |
| 190 | } |
| 191 | case 3: |
| 192 | { |
| 193 | void (*fptr)(void *__data, |
| 194 | unsigned long arg0, |
| 195 | unsigned long arg1, |
| 196 | unsigned long arg2) = func; |
| 197 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 198 | |
| 199 | lttng_syscall_get_arguments(current, regs, args); |
| 200 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 201 | fptr(event_priv->pub, args[0], args[1], args[2]); |
| 202 | break; |
| 203 | } |
| 204 | case 4: |
| 205 | { |
| 206 | void (*fptr)(void *__data, |
| 207 | unsigned long arg0, |
| 208 | unsigned long arg1, |
| 209 | unsigned long arg2, |
| 210 | unsigned long arg3) = func; |
| 211 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 212 | |
| 213 | lttng_syscall_get_arguments(current, regs, args); |
| 214 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 215 | fptr(event_priv->pub, args[0], args[1], args[2], args[3]); |
| 216 | break; |
| 217 | } |
| 218 | case 5: |
| 219 | { |
| 220 | void (*fptr)(void *__data, |
| 221 | unsigned long arg0, |
| 222 | unsigned long arg1, |
| 223 | unsigned long arg2, |
| 224 | unsigned long arg3, |
| 225 | unsigned long arg4) = func; |
| 226 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 227 | |
| 228 | lttng_syscall_get_arguments(current, regs, args); |
| 229 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 230 | fptr(event_priv->pub, args[0], args[1], args[2], args[3], args[4]); |
| 231 | break; |
| 232 | } |
| 233 | case 6: |
| 234 | { |
| 235 | void (*fptr)(void *__data, |
| 236 | unsigned long arg0, |
| 237 | unsigned long arg1, |
| 238 | unsigned long arg2, |
| 239 | unsigned long arg3, |
| 240 | unsigned long arg4, |
| 241 | unsigned long arg5) = func; |
| 242 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 243 | |
| 244 | lttng_syscall_get_arguments(current, regs, args); |
| 245 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 246 | fptr(event_priv->pub, args[0], args[1], args[2], |
| 247 | args[3], args[4], args[5]); |
| 248 | break; |
| 249 | } |
| 250 | default: |
| 251 | break; |
| 252 | } |
| 253 | } |
| 254 | |
| 255 | void syscall_entry_event_probe(void *__data, struct pt_regs *regs, long id) |
| 256 | { |
| 257 | struct lttng_kernel_syscall_table *syscall_table = __data; |
| 258 | struct hlist_head *action_list, *unknown_action_list; |
| 259 | const struct trace_syscall_entry *table, *entry; |
| 260 | size_t table_len; |
| 261 | |
| 262 | if (unlikely(in_compat_syscall())) { |
| 263 | struct lttng_syscall_filter *filter = syscall_table->sc_filter; |
| 264 | |
| 265 | if (id < 0 || id >= NR_compat_syscalls |
| 266 | || (!READ_ONCE(syscall_table->syscall_all_entry) && !test_bit(id, filter->sc_compat_entry))) { |
| 267 | /* System call filtered out. */ |
| 268 | return; |
| 269 | } |
| 270 | table = compat_sc_table.table; |
| 271 | table_len = compat_sc_table.len; |
| 272 | unknown_action_list = &syscall_table->compat_unknown_syscall_dispatch; |
| 273 | } else { |
| 274 | struct lttng_syscall_filter *filter = syscall_table->sc_filter; |
| 275 | |
| 276 | if (id < 0 || id >= NR_syscalls |
| 277 | || (!READ_ONCE(syscall_table->syscall_all_entry) && !test_bit(id, filter->sc_entry))) { |
| 278 | /* System call filtered out. */ |
| 279 | return; |
| 280 | } |
| 281 | table = sc_table.table; |
| 282 | table_len = sc_table.len; |
| 283 | unknown_action_list = &syscall_table->unknown_syscall_dispatch; |
| 284 | } |
| 285 | if (unlikely(id < 0 || id >= table_len)) { |
| 286 | syscall_entry_event_unknown(unknown_action_list, regs, id); |
| 287 | return; |
| 288 | } |
| 289 | |
| 290 | entry = &table[id]; |
| 291 | if (!entry->event_func) { |
| 292 | syscall_entry_event_unknown(unknown_action_list, regs, id); |
| 293 | return; |
| 294 | } |
| 295 | |
| 296 | if (unlikely(in_compat_syscall())) { |
| 297 | action_list = &syscall_table->compat_syscall_dispatch[id]; |
| 298 | } else { |
| 299 | action_list = &syscall_table->syscall_dispatch[id]; |
| 300 | } |
| 301 | if (unlikely(hlist_empty(action_list))) |
| 302 | return; |
| 303 | |
| 304 | syscall_entry_event_call_func(action_list, entry->event_func, entry->nrargs, regs); |
| 305 | } |
| 306 | |
| 307 | static void syscall_exit_event_unknown(struct hlist_head *unknown_action_list_head, |
| 308 | struct pt_regs *regs, long id, long ret) |
| 309 | { |
| 310 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 311 | struct lttng_kernel_event_common_private *event_priv; |
| 312 | |
| 313 | lttng_syscall_get_arguments(current, regs, args); |
| 314 | lttng_hlist_for_each_entry_rcu(event_priv, unknown_action_list_head, u.syscall.node) { |
| 315 | if (unlikely(in_compat_syscall())) |
| 316 | __event_probe__compat_syscall_exit_unknown(event_priv->pub, id, ret, |
| 317 | args); |
| 318 | else |
| 319 | __event_probe__syscall_exit_unknown(event_priv->pub, id, ret, args); |
| 320 | } |
| 321 | } |
| 322 | |
| 323 | static __always_inline |
| 324 | void syscall_exit_event_call_func(struct hlist_head *action_list, |
| 325 | void *func, unsigned int nrargs, |
| 326 | struct pt_regs *regs, long ret) |
| 327 | { |
| 328 | struct lttng_kernel_event_common_private *event_priv; |
| 329 | |
| 330 | switch (nrargs) { |
| 331 | case 0: |
| 332 | { |
| 333 | void (*fptr)(void *__data, long ret) = func; |
| 334 | |
| 335 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 336 | fptr(event_priv->pub, ret); |
| 337 | break; |
| 338 | } |
| 339 | case 1: |
| 340 | { |
| 341 | void (*fptr)(void *__data, |
| 342 | long ret, |
| 343 | unsigned long arg0) = func; |
| 344 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 345 | |
| 346 | lttng_syscall_get_arguments(current, regs, args); |
| 347 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 348 | fptr(event_priv->pub, ret, args[0]); |
| 349 | break; |
| 350 | } |
| 351 | case 2: |
| 352 | { |
| 353 | void (*fptr)(void *__data, |
| 354 | long ret, |
| 355 | unsigned long arg0, |
| 356 | unsigned long arg1) = func; |
| 357 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 358 | |
| 359 | lttng_syscall_get_arguments(current, regs, args); |
| 360 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 361 | fptr(event_priv->pub, ret, args[0], args[1]); |
| 362 | break; |
| 363 | } |
| 364 | case 3: |
| 365 | { |
| 366 | void (*fptr)(void *__data, |
| 367 | long ret, |
| 368 | unsigned long arg0, |
| 369 | unsigned long arg1, |
| 370 | unsigned long arg2) = func; |
| 371 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 372 | |
| 373 | lttng_syscall_get_arguments(current, regs, args); |
| 374 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 375 | fptr(event_priv->pub, ret, args[0], args[1], args[2]); |
| 376 | break; |
| 377 | } |
| 378 | case 4: |
| 379 | { |
| 380 | void (*fptr)(void *__data, |
| 381 | long ret, |
| 382 | unsigned long arg0, |
| 383 | unsigned long arg1, |
| 384 | unsigned long arg2, |
| 385 | unsigned long arg3) = func; |
| 386 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 387 | |
| 388 | lttng_syscall_get_arguments(current, regs, args); |
| 389 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 390 | fptr(event_priv->pub, ret, args[0], args[1], args[2], args[3]); |
| 391 | break; |
| 392 | } |
| 393 | case 5: |
| 394 | { |
| 395 | void (*fptr)(void *__data, |
| 396 | long ret, |
| 397 | unsigned long arg0, |
| 398 | unsigned long arg1, |
| 399 | unsigned long arg2, |
| 400 | unsigned long arg3, |
| 401 | unsigned long arg4) = func; |
| 402 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 403 | |
| 404 | lttng_syscall_get_arguments(current, regs, args); |
| 405 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 406 | fptr(event_priv->pub, ret, args[0], args[1], args[2], args[3], args[4]); |
| 407 | break; |
| 408 | } |
| 409 | case 6: |
| 410 | { |
| 411 | void (*fptr)(void *__data, |
| 412 | long ret, |
| 413 | unsigned long arg0, |
| 414 | unsigned long arg1, |
| 415 | unsigned long arg2, |
| 416 | unsigned long arg3, |
| 417 | unsigned long arg4, |
| 418 | unsigned long arg5) = func; |
| 419 | unsigned long args[LTTNG_SYSCALL_NR_ARGS]; |
| 420 | |
| 421 | lttng_syscall_get_arguments(current, regs, args); |
| 422 | lttng_hlist_for_each_entry_rcu(event_priv, action_list, u.syscall.node) |
| 423 | fptr(event_priv->pub, ret, args[0], args[1], args[2], |
| 424 | args[3], args[4], args[5]); |
| 425 | break; |
| 426 | } |
| 427 | default: |
| 428 | break; |
| 429 | } |
| 430 | } |
| 431 | |
| 432 | void syscall_exit_event_probe(void *__data, struct pt_regs *regs, long ret) |
| 433 | { |
| 434 | struct lttng_kernel_syscall_table *syscall_table = __data; |
| 435 | struct hlist_head *action_list, *unknown_action_list; |
| 436 | const struct trace_syscall_entry *table, *entry; |
| 437 | size_t table_len; |
| 438 | long id; |
| 439 | |
| 440 | id = syscall_get_nr(current, regs); |
| 441 | |
| 442 | if (unlikely(in_compat_syscall())) { |
| 443 | struct lttng_syscall_filter *filter = syscall_table->sc_filter; |
| 444 | |
| 445 | if (id < 0 || id >= NR_compat_syscalls |
| 446 | || (!READ_ONCE(syscall_table->syscall_all_exit) && !test_bit(id, filter->sc_compat_exit))) { |
| 447 | /* System call filtered out. */ |
| 448 | return; |
| 449 | } |
| 450 | table = compat_sc_exit_table.table; |
| 451 | table_len = compat_sc_exit_table.len; |
| 452 | unknown_action_list = &syscall_table->compat_unknown_syscall_exit_dispatch; |
| 453 | } else { |
| 454 | struct lttng_syscall_filter *filter = syscall_table->sc_filter; |
| 455 | |
| 456 | if (id < 0 || id >= NR_syscalls |
| 457 | || (!READ_ONCE(syscall_table->syscall_all_exit) && !test_bit(id, filter->sc_exit))) { |
| 458 | /* System call filtered out. */ |
| 459 | return; |
| 460 | } |
| 461 | table = sc_exit_table.table; |
| 462 | table_len = sc_exit_table.len; |
| 463 | unknown_action_list = &syscall_table->unknown_syscall_exit_dispatch; |
| 464 | } |
| 465 | if (unlikely(id < 0 || id >= table_len)) { |
| 466 | syscall_exit_event_unknown(unknown_action_list, regs, id, ret); |
| 467 | return; |
| 468 | } |
| 469 | |
| 470 | entry = &table[id]; |
| 471 | if (!entry->event_func) { |
| 472 | syscall_exit_event_unknown(unknown_action_list, regs, id, ret); |
| 473 | return; |
| 474 | } |
| 475 | |
| 476 | if (unlikely(in_compat_syscall())) { |
| 477 | action_list = &syscall_table->compat_syscall_exit_dispatch[id]; |
| 478 | } else { |
| 479 | action_list = &syscall_table->syscall_exit_dispatch[id]; |
| 480 | } |
| 481 | if (unlikely(hlist_empty(action_list))) |
| 482 | return; |
| 483 | |
| 484 | syscall_exit_event_call_func(action_list, entry->event_func, entry->nrargs, |
| 485 | regs, ret); |
| 486 | } |
| 487 | |
| 488 | static |
| 489 | struct lttng_kernel_syscall_table *get_syscall_table_from_enabler(struct lttng_event_enabler_common *event_enabler) |
| 490 | { |
| 491 | switch (event_enabler->enabler_type) { |
| 492 | case LTTNG_EVENT_ENABLER_TYPE_RECORDER: |
| 493 | { |
| 494 | struct lttng_event_recorder_enabler *event_recorder_enabler = |
| 495 | container_of(event_enabler, struct lttng_event_recorder_enabler, parent); |
| 496 | return &event_recorder_enabler->chan->priv->parent.syscall_table; |
| 497 | } |
| 498 | case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER: |
| 499 | { |
| 500 | struct lttng_event_notifier_enabler *event_notifier_enabler = |
| 501 | container_of(event_enabler, struct lttng_event_notifier_enabler, parent); |
| 502 | return &event_notifier_enabler->group->syscall_table; |
| 503 | } |
| 504 | default: |
| 505 | return NULL; |
| 506 | } |
| 507 | } |
| 508 | |
| 509 | static |
| 510 | struct lttng_kernel_syscall_table *get_syscall_table_from_event(struct lttng_kernel_event_common *event) |
| 511 | { |
| 512 | switch (event->type) { |
| 513 | case LTTNG_KERNEL_EVENT_TYPE_RECORDER: |
| 514 | { |
| 515 | struct lttng_kernel_event_recorder *event_recorder = |
| 516 | container_of(event, struct lttng_kernel_event_recorder, parent); |
| 517 | return &event_recorder->chan->priv->parent.syscall_table; |
| 518 | } |
| 519 | case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER: |
| 520 | { |
| 521 | struct lttng_kernel_event_notifier *event_notifier = |
| 522 | container_of(event, struct lttng_kernel_event_notifier, parent); |
| 523 | return &event_notifier->priv->group->syscall_table; |
| 524 | } |
| 525 | default: |
| 526 | return NULL; |
| 527 | } |
| 528 | } |
| 529 | |
| 530 | /* |
| 531 | * noinline to diminish caller stack size. |
| 532 | * Should be called with sessions lock held. |
| 533 | */ |
| 534 | static |
| 535 | int lttng_create_syscall_event_if_missing(const struct trace_syscall_entry *table, size_t table_len, |
| 536 | struct hlist_head *chan_table, struct lttng_event_recorder_enabler *syscall_event_enabler, |
| 537 | enum sc_type type) |
| 538 | { |
| 539 | struct lttng_event_ht *events_ht = lttng_get_event_ht_from_enabler(&syscall_event_enabler->parent); |
| 540 | struct lttng_kernel_channel_buffer *chan = syscall_event_enabler->chan; |
| 541 | unsigned int i; |
| 542 | |
| 543 | /* Allocate events for each syscall matching enabler, insert into table */ |
| 544 | for (i = 0; i < table_len; i++) { |
| 545 | const struct lttng_kernel_event_desc *desc = table[i].desc; |
| 546 | struct lttng_event_recorder_enabler *event_enabler; |
| 547 | struct lttng_kernel_abi_event ev; |
| 548 | struct lttng_kernel_event_common *event; |
| 549 | struct lttng_kernel_event_common_private *event_priv; |
| 550 | struct hlist_head *head; |
| 551 | bool found = false; |
| 552 | |
| 553 | if (!desc) { |
| 554 | /* Unknown syscall */ |
| 555 | continue; |
| 556 | } |
| 557 | if (!lttng_desc_match_enabler(desc, |
| 558 | lttng_event_recorder_enabler_as_enabler(syscall_event_enabler))) |
| 559 | continue; |
| 560 | /* |
| 561 | * Check if already created. |
| 562 | */ |
| 563 | head = utils_borrow_hash_table_bucket(events_ht->table, LTTNG_EVENT_HT_SIZE, desc->event_name); |
| 564 | lttng_hlist_for_each_entry(event_priv, head, hlist_node) { |
| 565 | if (lttng_event_enabler_desc_match_event(&syscall_event_enabler->parent, desc, event_priv->pub)) |
| 566 | found = true; |
| 567 | } |
| 568 | if (found) |
| 569 | continue; |
| 570 | |
| 571 | /* We need to create an event for this syscall/enabler. */ |
| 572 | memset(&ev, 0, sizeof(ev)); |
| 573 | switch (type) { |
| 574 | case SC_TYPE_ENTRY: |
| 575 | ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; |
| 576 | ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; |
| 577 | break; |
| 578 | case SC_TYPE_EXIT: |
| 579 | ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; |
| 580 | ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; |
| 581 | break; |
| 582 | case SC_TYPE_COMPAT_ENTRY: |
| 583 | ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; |
| 584 | ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; |
| 585 | break; |
| 586 | case SC_TYPE_COMPAT_EXIT: |
| 587 | ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; |
| 588 | ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; |
| 589 | break; |
| 590 | } |
| 591 | strncpy(ev.name, desc->event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1); |
| 592 | ev.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 593 | ev.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; |
| 594 | event_enabler = lttng_event_recorder_enabler_create(LTTNG_ENABLER_FORMAT_NAME, &ev, chan); |
| 595 | if (!event_enabler) { |
| 596 | return -ENOMEM; |
| 597 | } |
| 598 | event = _lttng_kernel_event_create(&event_enabler->parent, desc); |
| 599 | WARN_ON_ONCE(!event); |
| 600 | lttng_event_enabler_destroy(&event_enabler->parent); |
| 601 | if (IS_ERR(event)) { |
| 602 | /* |
| 603 | * If something goes wrong in event registration |
| 604 | * after the first one, we have no choice but to |
| 605 | * leave the previous events in there, until |
| 606 | * deleted by session teardown. |
| 607 | */ |
| 608 | return PTR_ERR(event); |
| 609 | } |
| 610 | hlist_add_head(&event->priv->u.syscall.node, &chan_table[i]); |
| 611 | } |
| 612 | return 0; |
| 613 | } |
| 614 | |
| 615 | static |
| 616 | int lttng_syscalls_populate_events(struct lttng_event_enabler_common *syscall_event_enabler) |
| 617 | { |
| 618 | struct lttng_kernel_syscall_table *syscall_table = get_syscall_table_from_enabler(syscall_event_enabler); |
| 619 | struct lttng_event_recorder_enabler *event_recorder_enabler; |
| 620 | struct lttng_kernel_channel_buffer *chan; |
| 621 | struct lttng_kernel_abi_event ev; |
| 622 | int ret; |
| 623 | |
| 624 | if (syscall_event_enabler->enabler_type != LTTNG_EVENT_ENABLER_TYPE_RECORDER) |
| 625 | return 0; |
| 626 | event_recorder_enabler = container_of(syscall_event_enabler, struct lttng_event_recorder_enabler, parent); |
| 627 | chan = event_recorder_enabler->chan; |
| 628 | |
| 629 | if (hlist_empty(&syscall_table->unknown_syscall_dispatch)) { |
| 630 | const struct lttng_kernel_event_desc *desc = |
| 631 | &__event_desc___syscall_entry_unknown; |
| 632 | struct lttng_kernel_event_common *event; |
| 633 | struct lttng_event_recorder_enabler *event_enabler; |
| 634 | |
| 635 | memset(&ev, 0, sizeof(ev)); |
| 636 | strncpy(ev.name, desc->event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN); |
| 637 | ev.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 638 | ev.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; |
| 639 | ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; |
| 640 | ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; |
| 641 | event_enabler = lttng_event_recorder_enabler_create(LTTNG_ENABLER_FORMAT_NAME, &ev, chan); |
| 642 | if (!event_enabler) { |
| 643 | return -ENOMEM; |
| 644 | } |
| 645 | event = _lttng_kernel_event_create(&event_enabler->parent, desc); |
| 646 | lttng_event_enabler_destroy(&event_enabler->parent); |
| 647 | WARN_ON_ONCE(!event); |
| 648 | if (IS_ERR(event)) { |
| 649 | return PTR_ERR(event); |
| 650 | } |
| 651 | hlist_add_head(&event->priv->u.syscall.node, &syscall_table->unknown_syscall_dispatch); |
| 652 | } |
| 653 | |
| 654 | if (hlist_empty(&syscall_table->compat_unknown_syscall_dispatch)) { |
| 655 | const struct lttng_kernel_event_desc *desc = |
| 656 | &__event_desc___compat_syscall_entry_unknown; |
| 657 | struct lttng_kernel_event_common *event; |
| 658 | struct lttng_event_recorder_enabler *event_enabler; |
| 659 | |
| 660 | memset(&ev, 0, sizeof(ev)); |
| 661 | strncpy(ev.name, desc->event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN); |
| 662 | ev.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 663 | ev.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; |
| 664 | ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; |
| 665 | ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; |
| 666 | event_enabler = lttng_event_recorder_enabler_create(LTTNG_ENABLER_FORMAT_NAME, &ev, chan); |
| 667 | if (!event_enabler) { |
| 668 | return -ENOMEM; |
| 669 | } |
| 670 | event = _lttng_kernel_event_create(&event_enabler->parent, desc); |
| 671 | WARN_ON_ONCE(!event); |
| 672 | lttng_event_enabler_destroy(&event_enabler->parent); |
| 673 | if (IS_ERR(event)) { |
| 674 | return PTR_ERR(event); |
| 675 | } |
| 676 | hlist_add_head(&event->priv->u.syscall.node, &syscall_table->compat_unknown_syscall_dispatch); |
| 677 | } |
| 678 | |
| 679 | if (hlist_empty(&syscall_table->compat_unknown_syscall_exit_dispatch)) { |
| 680 | const struct lttng_kernel_event_desc *desc = |
| 681 | &__event_desc___compat_syscall_exit_unknown; |
| 682 | struct lttng_kernel_event_common *event; |
| 683 | struct lttng_event_recorder_enabler *event_enabler; |
| 684 | |
| 685 | memset(&ev, 0, sizeof(ev)); |
| 686 | strncpy(ev.name, desc->event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN); |
| 687 | ev.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 688 | ev.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; |
| 689 | ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; |
| 690 | ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; |
| 691 | event_enabler = lttng_event_recorder_enabler_create(LTTNG_ENABLER_FORMAT_NAME, &ev, chan); |
| 692 | if (!event_enabler) { |
| 693 | return -ENOMEM; |
| 694 | } |
| 695 | event = _lttng_kernel_event_create(&event_enabler->parent, desc); |
| 696 | WARN_ON_ONCE(!event); |
| 697 | lttng_event_enabler_destroy(&event_enabler->parent); |
| 698 | if (IS_ERR(event)) { |
| 699 | return PTR_ERR(event); |
| 700 | } |
| 701 | hlist_add_head(&event->priv->u.syscall.node, &syscall_table->compat_unknown_syscall_exit_dispatch); |
| 702 | } |
| 703 | |
| 704 | if (hlist_empty(&syscall_table->unknown_syscall_exit_dispatch)) { |
| 705 | const struct lttng_kernel_event_desc *desc = |
| 706 | &__event_desc___syscall_exit_unknown; |
| 707 | struct lttng_kernel_event_common *event; |
| 708 | struct lttng_event_recorder_enabler *event_enabler; |
| 709 | |
| 710 | memset(&ev, 0, sizeof(ev)); |
| 711 | strncpy(ev.name, desc->event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN); |
| 712 | ev.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 713 | ev.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; |
| 714 | ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; |
| 715 | ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; |
| 716 | event_enabler = lttng_event_recorder_enabler_create(LTTNG_ENABLER_FORMAT_NAME, &ev, chan); |
| 717 | if (!event_enabler) { |
| 718 | return -ENOMEM; |
| 719 | } |
| 720 | event = _lttng_kernel_event_create(&event_enabler->parent, desc); |
| 721 | WARN_ON_ONCE(!event); |
| 722 | lttng_event_enabler_destroy(&event_enabler->parent); |
| 723 | if (IS_ERR(event)) { |
| 724 | return PTR_ERR(event); |
| 725 | } |
| 726 | hlist_add_head(&event->priv->u.syscall.node, &syscall_table->unknown_syscall_exit_dispatch); |
| 727 | } |
| 728 | |
| 729 | ret = lttng_create_syscall_event_if_missing(sc_table.table, sc_table.len, |
| 730 | syscall_table->syscall_dispatch, event_recorder_enabler, SC_TYPE_ENTRY); |
| 731 | if (ret) |
| 732 | return ret; |
| 733 | ret = lttng_create_syscall_event_if_missing(sc_exit_table.table, sc_exit_table.len, |
| 734 | syscall_table->syscall_exit_dispatch, event_recorder_enabler, SC_TYPE_EXIT); |
| 735 | if (ret) |
| 736 | return ret; |
| 737 | |
| 738 | #ifdef CONFIG_COMPAT |
| 739 | ret = lttng_create_syscall_event_if_missing(compat_sc_table.table, compat_sc_table.len, |
| 740 | syscall_table->compat_syscall_dispatch, event_recorder_enabler, SC_TYPE_COMPAT_ENTRY); |
| 741 | if (ret) |
| 742 | return ret; |
| 743 | ret = lttng_create_syscall_event_if_missing(compat_sc_exit_table.table, compat_sc_exit_table.len, |
| 744 | syscall_table->compat_syscall_exit_dispatch, event_recorder_enabler, SC_TYPE_COMPAT_EXIT); |
| 745 | if (ret) |
| 746 | return ret; |
| 747 | #endif |
| 748 | return ret; |
| 749 | } |
| 750 | |
| 751 | /* |
| 752 | * Should be called with sessions lock held. |
| 753 | */ |
| 754 | int lttng_syscalls_register_event(struct lttng_event_enabler_common *syscall_event_enabler) |
| 755 | { |
| 756 | struct lttng_kernel_syscall_table *syscall_table = get_syscall_table_from_enabler(syscall_event_enabler); |
| 757 | int ret; |
| 758 | |
| 759 | if (!syscall_table->syscall_dispatch) { |
| 760 | /* create syscall table mapping syscall to events */ |
| 761 | syscall_table->syscall_dispatch = kzalloc(sizeof(struct hlist_head) * sc_table.len, GFP_KERNEL); |
| 762 | if (!syscall_table->syscall_dispatch) |
| 763 | return -ENOMEM; |
| 764 | } |
| 765 | if (!syscall_table->syscall_exit_dispatch) { |
| 766 | /* create syscall table mapping syscall to events */ |
| 767 | syscall_table->syscall_exit_dispatch = kzalloc(sizeof(struct hlist_head) * sc_exit_table.len, GFP_KERNEL); |
| 768 | if (!syscall_table->syscall_exit_dispatch) |
| 769 | return -ENOMEM; |
| 770 | } |
| 771 | |
| 772 | |
| 773 | #ifdef CONFIG_COMPAT |
| 774 | if (!syscall_table->compat_syscall_dispatch) { |
| 775 | /* create syscall table mapping compat syscall to events */ |
| 776 | syscall_table->compat_syscall_dispatch = kzalloc(sizeof(struct hlist_head) * compat_sc_table.len, GFP_KERNEL); |
| 777 | if (!syscall_table->compat_syscall_dispatch) |
| 778 | return -ENOMEM; |
| 779 | } |
| 780 | |
| 781 | if (!syscall_table->compat_syscall_exit_dispatch) { |
| 782 | /* create syscall table mapping compat syscall to events */ |
| 783 | syscall_table->compat_syscall_exit_dispatch = kzalloc(sizeof(struct hlist_head) * compat_sc_exit_table.len, GFP_KERNEL); |
| 784 | if (!syscall_table->compat_syscall_exit_dispatch) |
| 785 | return -ENOMEM; |
| 786 | } |
| 787 | #endif |
| 788 | if (!syscall_table->sc_filter) { |
| 789 | syscall_table->sc_filter = kzalloc(sizeof(struct lttng_syscall_filter), |
| 790 | GFP_KERNEL); |
| 791 | if (!syscall_table->sc_filter) |
| 792 | return -ENOMEM; |
| 793 | } |
| 794 | |
| 795 | ret = lttng_syscalls_populate_events(syscall_event_enabler); |
| 796 | if (ret) |
| 797 | return ret; |
| 798 | |
| 799 | wrapper_vmalloc_sync_mappings(); |
| 800 | |
| 801 | if (!syscall_table->sys_enter_registered) { |
| 802 | ret = lttng_wrapper_tracepoint_probe_register("sys_enter", |
| 803 | (void *) syscall_entry_event_probe, syscall_table); |
| 804 | if (ret) |
| 805 | return ret; |
| 806 | syscall_table->sys_enter_registered = 1; |
| 807 | } |
| 808 | if (!syscall_table->sys_exit_registered) { |
| 809 | ret = lttng_wrapper_tracepoint_probe_register("sys_exit", |
| 810 | (void *) syscall_exit_event_probe, syscall_table); |
| 811 | if (ret) { |
| 812 | WARN_ON_ONCE(lttng_wrapper_tracepoint_probe_unregister("sys_enter", |
| 813 | (void *) syscall_entry_event_probe, syscall_table)); |
| 814 | return ret; |
| 815 | } |
| 816 | syscall_table->sys_exit_registered = 1; |
| 817 | } |
| 818 | |
| 819 | ret = lttng_syscalls_create_matching_event_notifiers(syscall_event_enabler); |
| 820 | if (ret) |
| 821 | return ret; |
| 822 | |
| 823 | return ret; |
| 824 | } |
| 825 | |
| 826 | static |
| 827 | int create_unknown_event_notifier( |
| 828 | struct lttng_event_notifier_enabler *event_notifier_enabler, |
| 829 | enum sc_type type) |
| 830 | { |
| 831 | struct lttng_event_ht *events_ht = lttng_get_event_ht_from_enabler(&event_notifier_enabler->parent); |
| 832 | struct lttng_kernel_event_common_private *event_priv; |
| 833 | struct lttng_kernel_event_common *event; |
| 834 | const struct lttng_kernel_event_desc *desc; |
| 835 | struct lttng_event_notifier_group *group = event_notifier_enabler->group; |
| 836 | struct lttng_kernel_syscall_table *syscall_table = &group->syscall_table; |
| 837 | struct lttng_kernel_abi_event_notifier event_notifier_param; |
| 838 | uint64_t user_token = event_notifier_enabler->parent.user_token; |
| 839 | uint64_t error_counter_index = event_notifier_enabler->error_counter_index; |
| 840 | struct lttng_event_enabler_common *base_enabler = lttng_event_notifier_enabler_as_enabler( |
| 841 | event_notifier_enabler); |
| 842 | struct hlist_head *unknown_dispatch_list; |
| 843 | int ret = 0; |
| 844 | bool found = false; |
| 845 | enum lttng_kernel_abi_syscall_abi abi; |
| 846 | enum lttng_kernel_abi_syscall_entryexit entryexit; |
| 847 | struct hlist_head *head; |
| 848 | |
| 849 | switch (type) { |
| 850 | case SC_TYPE_ENTRY: |
| 851 | desc = &__event_desc___syscall_entry_unknown; |
| 852 | unknown_dispatch_list = &syscall_table->unknown_syscall_dispatch; |
| 853 | entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; |
| 854 | abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; |
| 855 | break; |
| 856 | case SC_TYPE_EXIT: |
| 857 | desc = &__event_desc___syscall_exit_unknown; |
| 858 | unknown_dispatch_list = &syscall_table->unknown_syscall_exit_dispatch; |
| 859 | entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; |
| 860 | abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; |
| 861 | break; |
| 862 | case SC_TYPE_COMPAT_ENTRY: |
| 863 | desc = &__event_desc___compat_syscall_entry_unknown; |
| 864 | unknown_dispatch_list = &syscall_table->compat_unknown_syscall_dispatch; |
| 865 | entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; |
| 866 | abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; |
| 867 | break; |
| 868 | case SC_TYPE_COMPAT_EXIT: |
| 869 | desc = &__event_desc___compat_syscall_exit_unknown; |
| 870 | unknown_dispatch_list = &syscall_table->compat_unknown_syscall_exit_dispatch; |
| 871 | entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; |
| 872 | abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; |
| 873 | break; |
| 874 | default: |
| 875 | BUG_ON(1); |
| 876 | } |
| 877 | |
| 878 | /* |
| 879 | * Check if already created. |
| 880 | */ |
| 881 | head = utils_borrow_hash_table_bucket(events_ht->table, LTTNG_EVENT_HT_SIZE, desc->event_name); |
| 882 | lttng_hlist_for_each_entry(event_priv, head, hlist_node) { |
| 883 | if (lttng_event_enabler_desc_match_event(base_enabler, desc, event_priv->pub)) |
| 884 | found = true; |
| 885 | } |
| 886 | if (found) |
| 887 | goto end; |
| 888 | |
| 889 | memset(&event_notifier_param, 0, sizeof(event_notifier_param)); |
| 890 | strncat(event_notifier_param.event.name, desc->event_name, |
| 891 | LTTNG_KERNEL_ABI_SYM_NAME_LEN - strlen(event_notifier_param.event.name) - 1); |
| 892 | |
| 893 | event_notifier_param.event.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 894 | |
| 895 | event_notifier_param.event.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; |
| 896 | event_notifier_param.event.token = user_token; |
| 897 | event_notifier_param.event.u.syscall.abi = abi; |
| 898 | event_notifier_param.event.u.syscall.entryexit = entryexit; |
| 899 | event_notifier_param.error_counter_index = error_counter_index; |
| 900 | |
| 901 | event_notifier_enabler = lttng_event_notifier_enabler_create(LTTNG_ENABLER_FORMAT_NAME, |
| 902 | &event_notifier_param, group); |
| 903 | WARN_ON_ONCE(!event_notifier_enabler); |
| 904 | event = _lttng_kernel_event_create(&event_notifier_enabler->parent, desc); |
| 905 | lttng_event_enabler_destroy(&event_notifier_enabler->parent); |
| 906 | if (IS_ERR(event)) { |
| 907 | printk(KERN_INFO "Unable to create unknown notifier %s\n", |
| 908 | desc->event_name); |
| 909 | ret = -ENOMEM; |
| 910 | goto end; |
| 911 | } |
| 912 | |
| 913 | hlist_add_head_rcu(&event->priv->u.syscall.node, unknown_dispatch_list); |
| 914 | |
| 915 | end: |
| 916 | return ret; |
| 917 | } |
| 918 | |
| 919 | static int create_matching_event_notifiers( |
| 920 | struct lttng_event_notifier_enabler *syscall_event_notifier_enabler, |
| 921 | const struct trace_syscall_entry *table, |
| 922 | size_t table_len, enum sc_type type) |
| 923 | { |
| 924 | struct lttng_event_ht *events_ht = lttng_get_event_ht_from_enabler(&syscall_event_notifier_enabler->parent); |
| 925 | struct lttng_event_notifier_group *group = syscall_event_notifier_enabler->group; |
| 926 | const struct lttng_kernel_event_desc *desc; |
| 927 | uint64_t user_token = syscall_event_notifier_enabler->parent.user_token; |
| 928 | uint64_t error_counter_index = syscall_event_notifier_enabler->error_counter_index; |
| 929 | unsigned int i; |
| 930 | int ret = 0; |
| 931 | |
| 932 | /* iterate over all syscall and create event_notifier that match */ |
| 933 | for (i = 0; i < table_len; i++) { |
| 934 | struct lttng_event_notifier_enabler *event_notifier_enabler; |
| 935 | struct lttng_kernel_event_common_private *event_priv; |
| 936 | struct lttng_kernel_event_common *event; |
| 937 | struct lttng_kernel_abi_event_notifier event_notifier_param; |
| 938 | struct hlist_head *head; |
| 939 | int found = 0; |
| 940 | |
| 941 | desc = table[i].desc; |
| 942 | if (!desc) { |
| 943 | /* Unknown syscall */ |
| 944 | continue; |
| 945 | } |
| 946 | |
| 947 | if (!lttng_desc_match_enabler(desc, |
| 948 | lttng_event_notifier_enabler_as_enabler(syscall_event_notifier_enabler))) |
| 949 | continue; |
| 950 | |
| 951 | /* |
| 952 | * Check if already created. |
| 953 | */ |
| 954 | head = utils_borrow_hash_table_bucket(events_ht->table, LTTNG_EVENT_HT_SIZE, desc->event_name); |
| 955 | lttng_hlist_for_each_entry(event_priv, head, hlist_node) { |
| 956 | if (lttng_event_enabler_desc_match_event(&syscall_event_notifier_enabler->parent, desc, event_priv->pub)) |
| 957 | found = 1; |
| 958 | } |
| 959 | if (found) |
| 960 | continue; |
| 961 | |
| 962 | memset(&event_notifier_param, 0, sizeof(event_notifier_param)); |
| 963 | switch (type) { |
| 964 | case SC_TYPE_ENTRY: |
| 965 | event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; |
| 966 | event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; |
| 967 | break; |
| 968 | case SC_TYPE_EXIT: |
| 969 | event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; |
| 970 | event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; |
| 971 | break; |
| 972 | case SC_TYPE_COMPAT_ENTRY: |
| 973 | event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; |
| 974 | event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; |
| 975 | break; |
| 976 | case SC_TYPE_COMPAT_EXIT: |
| 977 | event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; |
| 978 | event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; |
| 979 | break; |
| 980 | } |
| 981 | strncat(event_notifier_param.event.name, desc->event_name, |
| 982 | LTTNG_KERNEL_ABI_SYM_NAME_LEN - strlen(event_notifier_param.event.name) - 1); |
| 983 | event_notifier_param.event.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 984 | event_notifier_param.event.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; |
| 985 | event_notifier_param.event.token = user_token; |
| 986 | event_notifier_param.error_counter_index = error_counter_index; |
| 987 | |
| 988 | event_notifier_enabler = lttng_event_notifier_enabler_create(LTTNG_ENABLER_FORMAT_NAME, |
| 989 | &event_notifier_param, group); |
| 990 | WARN_ON_ONCE(!event_notifier_enabler); |
| 991 | event = _lttng_kernel_event_create(&event_notifier_enabler->parent, desc); |
| 992 | lttng_event_enabler_destroy(&event_notifier_enabler->parent); |
| 993 | if (IS_ERR(event)) { |
| 994 | printk(KERN_INFO "Unable to create event_notifier %s\n", |
| 995 | desc->event_name); |
| 996 | ret = -ENOMEM; |
| 997 | goto end; |
| 998 | } |
| 999 | |
| 1000 | event->priv->u.syscall.syscall_id = i; |
| 1001 | } |
| 1002 | |
| 1003 | end: |
| 1004 | return ret; |
| 1005 | |
| 1006 | } |
| 1007 | |
| 1008 | static |
| 1009 | int lttng_syscalls_create_matching_event_notifiers(struct lttng_event_enabler_common *event_enabler) |
| 1010 | { |
| 1011 | int ret; |
| 1012 | enum lttng_kernel_abi_syscall_entryexit entryexit = |
| 1013 | event_enabler->event_param.u.syscall.entryexit; |
| 1014 | struct lttng_event_notifier_enabler *event_notifier_enabler; |
| 1015 | |
| 1016 | if (event_enabler->enabler_type != LTTNG_EVENT_ENABLER_TYPE_NOTIFIER) |
| 1017 | return 0; |
| 1018 | event_notifier_enabler = container_of(event_enabler, struct lttng_event_notifier_enabler, parent); |
| 1019 | |
| 1020 | if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRY || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT) { |
| 1021 | ret = create_matching_event_notifiers(event_notifier_enabler, |
| 1022 | sc_table.table, sc_table.len, SC_TYPE_ENTRY); |
| 1023 | if (ret) |
| 1024 | goto end; |
| 1025 | |
| 1026 | ret = create_matching_event_notifiers(event_notifier_enabler, |
| 1027 | compat_sc_table.table, compat_sc_table.len, |
| 1028 | SC_TYPE_COMPAT_ENTRY); |
| 1029 | if (ret) |
| 1030 | goto end; |
| 1031 | |
| 1032 | ret = create_unknown_event_notifier(event_notifier_enabler, |
| 1033 | SC_TYPE_ENTRY); |
| 1034 | if (ret) |
| 1035 | goto end; |
| 1036 | |
| 1037 | ret = create_unknown_event_notifier(event_notifier_enabler, |
| 1038 | SC_TYPE_COMPAT_ENTRY); |
| 1039 | if (ret) |
| 1040 | goto end; |
| 1041 | } |
| 1042 | |
| 1043 | if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_EXIT || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT) { |
| 1044 | ret = create_matching_event_notifiers(event_notifier_enabler, |
| 1045 | sc_exit_table.table, sc_exit_table.len, |
| 1046 | SC_TYPE_EXIT); |
| 1047 | if (ret) |
| 1048 | goto end; |
| 1049 | |
| 1050 | ret = create_unknown_event_notifier(event_notifier_enabler, |
| 1051 | SC_TYPE_EXIT); |
| 1052 | if (ret) |
| 1053 | goto end; |
| 1054 | |
| 1055 | ret = create_matching_event_notifiers(event_notifier_enabler, |
| 1056 | compat_sc_exit_table.table, compat_sc_exit_table.len, |
| 1057 | SC_TYPE_COMPAT_EXIT); |
| 1058 | if (ret) |
| 1059 | goto end; |
| 1060 | |
| 1061 | ret = create_unknown_event_notifier(event_notifier_enabler, |
| 1062 | SC_TYPE_COMPAT_EXIT); |
| 1063 | if (ret) |
| 1064 | goto end; |
| 1065 | } |
| 1066 | |
| 1067 | end: |
| 1068 | return ret; |
| 1069 | } |
| 1070 | |
| 1071 | int lttng_syscalls_unregister_syscall_table(struct lttng_kernel_syscall_table *syscall_table) |
| 1072 | { |
| 1073 | int ret; |
| 1074 | |
| 1075 | if (!syscall_table->syscall_dispatch) |
| 1076 | return 0; |
| 1077 | if (syscall_table->sys_enter_registered) { |
| 1078 | ret = lttng_wrapper_tracepoint_probe_unregister("sys_enter", |
| 1079 | (void *) syscall_entry_event_probe, syscall_table); |
| 1080 | if (ret) |
| 1081 | return ret; |
| 1082 | syscall_table->sys_enter_registered = 0; |
| 1083 | } |
| 1084 | if (syscall_table->sys_exit_registered) { |
| 1085 | ret = lttng_wrapper_tracepoint_probe_unregister("sys_exit", |
| 1086 | (void *) syscall_exit_event_probe, syscall_table); |
| 1087 | if (ret) |
| 1088 | return ret; |
| 1089 | syscall_table->sys_exit_registered = 0; |
| 1090 | } |
| 1091 | return 0; |
| 1092 | } |
| 1093 | |
| 1094 | int lttng_syscalls_destroy_syscall_table(struct lttng_kernel_syscall_table *syscall_table) |
| 1095 | { |
| 1096 | kfree(syscall_table->syscall_dispatch); |
| 1097 | kfree(syscall_table->syscall_exit_dispatch); |
| 1098 | #ifdef CONFIG_COMPAT |
| 1099 | kfree(syscall_table->compat_syscall_dispatch); |
| 1100 | kfree(syscall_table->compat_syscall_exit_dispatch); |
| 1101 | #endif |
| 1102 | kfree(syscall_table->sc_filter); |
| 1103 | return 0; |
| 1104 | } |
| 1105 | |
| 1106 | static |
| 1107 | int get_syscall_nr(const char *syscall_name) |
| 1108 | { |
| 1109 | int syscall_nr = -1; |
| 1110 | int i; |
| 1111 | |
| 1112 | for (i = 0; i < sc_table.len; i++) { |
| 1113 | const struct trace_syscall_entry *entry; |
| 1114 | const char *it_name; |
| 1115 | |
| 1116 | entry = &sc_table.table[i]; |
| 1117 | if (!entry->desc) |
| 1118 | continue; |
| 1119 | it_name = entry->desc->event_name; |
| 1120 | it_name += strlen(SYSCALL_ENTRY_STR); |
| 1121 | if (!strcmp(syscall_name, it_name)) { |
| 1122 | syscall_nr = i; |
| 1123 | break; |
| 1124 | } |
| 1125 | } |
| 1126 | return syscall_nr; |
| 1127 | } |
| 1128 | |
| 1129 | static |
| 1130 | int get_compat_syscall_nr(const char *syscall_name) |
| 1131 | { |
| 1132 | int syscall_nr = -1; |
| 1133 | int i; |
| 1134 | |
| 1135 | for (i = 0; i < compat_sc_table.len; i++) { |
| 1136 | const struct trace_syscall_entry *entry; |
| 1137 | const char *it_name; |
| 1138 | |
| 1139 | entry = &compat_sc_table.table[i]; |
| 1140 | if (!entry->desc) |
| 1141 | continue; |
| 1142 | it_name = entry->desc->event_name; |
| 1143 | it_name += strlen(COMPAT_SYSCALL_ENTRY_STR); |
| 1144 | if (!strcmp(syscall_name, it_name)) { |
| 1145 | syscall_nr = i; |
| 1146 | break; |
| 1147 | } |
| 1148 | } |
| 1149 | return syscall_nr; |
| 1150 | } |
| 1151 | |
| 1152 | static |
| 1153 | uint32_t get_sc_tables_len(void) |
| 1154 | { |
| 1155 | return sc_table.len + compat_sc_table.len; |
| 1156 | } |
| 1157 | |
| 1158 | static |
| 1159 | const char *get_syscall_name(const char *desc_name, |
| 1160 | enum lttng_syscall_abi abi, |
| 1161 | enum lttng_syscall_entryexit entryexit) |
| 1162 | { |
| 1163 | size_t prefix_len = 0; |
| 1164 | |
| 1165 | |
| 1166 | switch (entryexit) { |
| 1167 | case LTTNG_SYSCALL_ENTRY: |
| 1168 | switch (abi) { |
| 1169 | case LTTNG_SYSCALL_ABI_NATIVE: |
| 1170 | prefix_len = strlen(SYSCALL_ENTRY_STR); |
| 1171 | break; |
| 1172 | case LTTNG_SYSCALL_ABI_COMPAT: |
| 1173 | prefix_len = strlen(COMPAT_SYSCALL_ENTRY_STR); |
| 1174 | break; |
| 1175 | } |
| 1176 | break; |
| 1177 | case LTTNG_SYSCALL_EXIT: |
| 1178 | switch (abi) { |
| 1179 | case LTTNG_SYSCALL_ABI_NATIVE: |
| 1180 | prefix_len = strlen(SYSCALL_EXIT_STR); |
| 1181 | break; |
| 1182 | case LTTNG_SYSCALL_ABI_COMPAT: |
| 1183 | prefix_len = strlen(COMPAT_SYSCALL_EXIT_STR); |
| 1184 | break; |
| 1185 | } |
| 1186 | break; |
| 1187 | } |
| 1188 | WARN_ON_ONCE(prefix_len == 0); |
| 1189 | return desc_name + prefix_len; |
| 1190 | } |
| 1191 | |
| 1192 | static |
| 1193 | int lttng_syscall_filter_enable( |
| 1194 | struct lttng_syscall_filter *filter, |
| 1195 | const char *desc_name, enum lttng_syscall_abi abi, |
| 1196 | enum lttng_syscall_entryexit entryexit) |
| 1197 | { |
| 1198 | const char *syscall_name; |
| 1199 | unsigned long *bitmap; |
| 1200 | int syscall_nr; |
| 1201 | |
| 1202 | syscall_name = get_syscall_name(desc_name, abi, entryexit); |
| 1203 | |
| 1204 | switch (abi) { |
| 1205 | case LTTNG_SYSCALL_ABI_NATIVE: |
| 1206 | syscall_nr = get_syscall_nr(syscall_name); |
| 1207 | break; |
| 1208 | case LTTNG_SYSCALL_ABI_COMPAT: |
| 1209 | syscall_nr = get_compat_syscall_nr(syscall_name); |
| 1210 | break; |
| 1211 | default: |
| 1212 | return -EINVAL; |
| 1213 | } |
| 1214 | if (syscall_nr < 0) |
| 1215 | return -ENOENT; |
| 1216 | |
| 1217 | switch (entryexit) { |
| 1218 | case LTTNG_SYSCALL_ENTRY: |
| 1219 | switch (abi) { |
| 1220 | case LTTNG_SYSCALL_ABI_NATIVE: |
| 1221 | bitmap = filter->sc_entry; |
| 1222 | break; |
| 1223 | case LTTNG_SYSCALL_ABI_COMPAT: |
| 1224 | bitmap = filter->sc_compat_entry; |
| 1225 | break; |
| 1226 | default: |
| 1227 | return -EINVAL; |
| 1228 | } |
| 1229 | break; |
| 1230 | case LTTNG_SYSCALL_EXIT: |
| 1231 | switch (abi) { |
| 1232 | case LTTNG_SYSCALL_ABI_NATIVE: |
| 1233 | bitmap = filter->sc_exit; |
| 1234 | break; |
| 1235 | case LTTNG_SYSCALL_ABI_COMPAT: |
| 1236 | bitmap = filter->sc_compat_exit; |
| 1237 | break; |
| 1238 | default: |
| 1239 | return -EINVAL; |
| 1240 | } |
| 1241 | break; |
| 1242 | default: |
| 1243 | return -EINVAL; |
| 1244 | } |
| 1245 | if (test_bit(syscall_nr, bitmap)) |
| 1246 | return -EEXIST; |
| 1247 | bitmap_set(bitmap, syscall_nr, 1); |
| 1248 | return 0; |
| 1249 | } |
| 1250 | |
| 1251 | int lttng_syscall_filter_enable_event(struct lttng_kernel_event_common *event) |
| 1252 | { |
| 1253 | struct lttng_kernel_syscall_table *syscall_table = get_syscall_table_from_event(event); |
| 1254 | int ret; |
| 1255 | |
| 1256 | WARN_ON_ONCE(event->priv->instrumentation != LTTNG_KERNEL_ABI_SYSCALL); |
| 1257 | |
| 1258 | ret = lttng_syscall_filter_enable(syscall_table->sc_filter, |
| 1259 | event->priv->desc->event_name, event->priv->u.syscall.abi, |
| 1260 | event->priv->u.syscall.entryexit); |
| 1261 | if (ret) |
| 1262 | return ret; |
| 1263 | |
| 1264 | switch (event->type) { |
| 1265 | case LTTNG_KERNEL_EVENT_TYPE_RECORDER: |
| 1266 | break; |
| 1267 | case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER: |
| 1268 | { |
| 1269 | unsigned int syscall_id = event->priv->u.syscall.syscall_id; |
| 1270 | struct hlist_head *dispatch_list; |
| 1271 | |
| 1272 | switch (event->priv->u.syscall.entryexit) { |
| 1273 | case LTTNG_SYSCALL_ENTRY: |
| 1274 | switch (event->priv->u.syscall.abi) { |
| 1275 | case LTTNG_SYSCALL_ABI_NATIVE: |
| 1276 | dispatch_list = &syscall_table->syscall_dispatch[syscall_id]; |
| 1277 | break; |
| 1278 | case LTTNG_SYSCALL_ABI_COMPAT: |
| 1279 | dispatch_list = &syscall_table->compat_syscall_dispatch[syscall_id]; |
| 1280 | break; |
| 1281 | default: |
| 1282 | ret = -EINVAL; |
| 1283 | goto end; |
| 1284 | } |
| 1285 | break; |
| 1286 | case LTTNG_SYSCALL_EXIT: |
| 1287 | switch (event->priv->u.syscall.abi) { |
| 1288 | case LTTNG_SYSCALL_ABI_NATIVE: |
| 1289 | dispatch_list = &syscall_table->syscall_exit_dispatch[syscall_id]; |
| 1290 | break; |
| 1291 | case LTTNG_SYSCALL_ABI_COMPAT: |
| 1292 | dispatch_list = &syscall_table->compat_syscall_exit_dispatch[syscall_id]; |
| 1293 | break; |
| 1294 | default: |
| 1295 | ret = -EINVAL; |
| 1296 | goto end; |
| 1297 | } |
| 1298 | break; |
| 1299 | default: |
| 1300 | ret = -EINVAL; |
| 1301 | goto end; |
| 1302 | } |
| 1303 | |
| 1304 | hlist_add_head_rcu(&event->priv->u.syscall.node, dispatch_list); |
| 1305 | break; |
| 1306 | } |
| 1307 | default: |
| 1308 | WARN_ON_ONCE(1); |
| 1309 | return -ENOSYS; |
| 1310 | } |
| 1311 | end: |
| 1312 | return ret; |
| 1313 | } |
| 1314 | |
| 1315 | static |
| 1316 | int lttng_syscall_filter_disable(struct lttng_syscall_filter *filter, |
| 1317 | const char *desc_name, enum lttng_syscall_abi abi, |
| 1318 | enum lttng_syscall_entryexit entryexit) |
| 1319 | { |
| 1320 | const char *syscall_name; |
| 1321 | unsigned long *bitmap; |
| 1322 | int syscall_nr; |
| 1323 | |
| 1324 | syscall_name = get_syscall_name(desc_name, abi, entryexit); |
| 1325 | |
| 1326 | switch (abi) { |
| 1327 | case LTTNG_SYSCALL_ABI_NATIVE: |
| 1328 | syscall_nr = get_syscall_nr(syscall_name); |
| 1329 | break; |
| 1330 | case LTTNG_SYSCALL_ABI_COMPAT: |
| 1331 | syscall_nr = get_compat_syscall_nr(syscall_name); |
| 1332 | break; |
| 1333 | default: |
| 1334 | return -EINVAL; |
| 1335 | } |
| 1336 | if (syscall_nr < 0) |
| 1337 | return -ENOENT; |
| 1338 | |
| 1339 | switch (entryexit) { |
| 1340 | case LTTNG_SYSCALL_ENTRY: |
| 1341 | switch (abi) { |
| 1342 | case LTTNG_SYSCALL_ABI_NATIVE: |
| 1343 | bitmap = filter->sc_entry; |
| 1344 | break; |
| 1345 | case LTTNG_SYSCALL_ABI_COMPAT: |
| 1346 | bitmap = filter->sc_compat_entry; |
| 1347 | break; |
| 1348 | default: |
| 1349 | return -EINVAL; |
| 1350 | } |
| 1351 | break; |
| 1352 | case LTTNG_SYSCALL_EXIT: |
| 1353 | switch (abi) { |
| 1354 | case LTTNG_SYSCALL_ABI_NATIVE: |
| 1355 | bitmap = filter->sc_exit; |
| 1356 | break; |
| 1357 | case LTTNG_SYSCALL_ABI_COMPAT: |
| 1358 | bitmap = filter->sc_compat_exit; |
| 1359 | break; |
| 1360 | default: |
| 1361 | return -EINVAL; |
| 1362 | } |
| 1363 | break; |
| 1364 | default: |
| 1365 | return -EINVAL; |
| 1366 | } |
| 1367 | if (!test_bit(syscall_nr, bitmap)) |
| 1368 | return -EEXIST; |
| 1369 | bitmap_clear(bitmap, syscall_nr, 1); |
| 1370 | |
| 1371 | return 0; |
| 1372 | } |
| 1373 | |
| 1374 | int lttng_syscall_filter_disable_event(struct lttng_kernel_event_common *event) |
| 1375 | { |
| 1376 | struct lttng_kernel_syscall_table *syscall_table = get_syscall_table_from_event(event); |
| 1377 | int ret; |
| 1378 | |
| 1379 | ret = lttng_syscall_filter_disable(syscall_table->sc_filter, |
| 1380 | event->priv->desc->event_name, event->priv->u.syscall.abi, |
| 1381 | event->priv->u.syscall.entryexit); |
| 1382 | if (ret) |
| 1383 | return ret; |
| 1384 | |
| 1385 | switch (event->type) { |
| 1386 | case LTTNG_KERNEL_EVENT_TYPE_RECORDER: |
| 1387 | break; |
| 1388 | case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER: |
| 1389 | { |
| 1390 | hlist_del_rcu(&event->priv->u.syscall.node); |
| 1391 | break; |
| 1392 | } |
| 1393 | default: |
| 1394 | WARN_ON_ONCE(1); |
| 1395 | return -ENOSYS; |
| 1396 | } |
| 1397 | return 0; |
| 1398 | } |
| 1399 | |
| 1400 | void lttng_syscall_table_set_wildcard_all(struct lttng_event_enabler_common *event_enabler) |
| 1401 | { |
| 1402 | struct lttng_kernel_syscall_table *syscall_table = get_syscall_table_from_enabler(event_enabler); |
| 1403 | enum lttng_kernel_abi_syscall_entryexit entryexit; |
| 1404 | int enabled = event_enabler->enabled; |
| 1405 | |
| 1406 | if (event_enabler->event_param.instrumentation != LTTNG_KERNEL_ABI_SYSCALL) |
| 1407 | return; |
| 1408 | if (event_enabler->event_param.u.syscall.abi != LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL) |
| 1409 | return; |
| 1410 | if (event_enabler->event_param.u.syscall.match != LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME) |
| 1411 | return; |
| 1412 | if (strcmp(event_enabler->event_param.name, "*")) |
| 1413 | return; |
| 1414 | |
| 1415 | entryexit = event_enabler->event_param.u.syscall.entryexit; |
| 1416 | if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRY || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT) |
| 1417 | WRITE_ONCE(syscall_table->syscall_all_entry, enabled); |
| 1418 | |
| 1419 | if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_EXIT || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT) |
| 1420 | WRITE_ONCE(syscall_table->syscall_all_exit, enabled); |
| 1421 | } |
| 1422 | |
| 1423 | static |
| 1424 | const struct trace_syscall_entry *syscall_list_get_entry(loff_t *pos) |
| 1425 | { |
| 1426 | const struct trace_syscall_entry *entry; |
| 1427 | int iter = 0; |
| 1428 | |
| 1429 | for (entry = sc_table.table; |
| 1430 | entry < sc_table.table + sc_table.len; |
| 1431 | entry++) { |
| 1432 | if (iter++ >= *pos) |
| 1433 | return entry; |
| 1434 | } |
| 1435 | for (entry = compat_sc_table.table; |
| 1436 | entry < compat_sc_table.table + compat_sc_table.len; |
| 1437 | entry++) { |
| 1438 | if (iter++ >= *pos) |
| 1439 | return entry; |
| 1440 | } |
| 1441 | /* End of list */ |
| 1442 | return NULL; |
| 1443 | } |
| 1444 | |
| 1445 | static |
| 1446 | void *syscall_list_start(struct seq_file *m, loff_t *pos) |
| 1447 | { |
| 1448 | return (void *) syscall_list_get_entry(pos); |
| 1449 | } |
| 1450 | |
| 1451 | static |
| 1452 | void *syscall_list_next(struct seq_file *m, void *p, loff_t *ppos) |
| 1453 | { |
| 1454 | (*ppos)++; |
| 1455 | return (void *) syscall_list_get_entry(ppos); |
| 1456 | } |
| 1457 | |
| 1458 | static |
| 1459 | void syscall_list_stop(struct seq_file *m, void *p) |
| 1460 | { |
| 1461 | } |
| 1462 | |
| 1463 | static |
| 1464 | int get_sc_table(const struct trace_syscall_entry *entry, |
| 1465 | const struct trace_syscall_entry **table, |
| 1466 | unsigned int *bitness) |
| 1467 | { |
| 1468 | if (entry >= sc_table.table && entry < sc_table.table + sc_table.len) { |
| 1469 | if (bitness) |
| 1470 | *bitness = BITS_PER_LONG; |
| 1471 | if (table) |
| 1472 | *table = sc_table.table; |
| 1473 | return 0; |
| 1474 | } |
| 1475 | if (!(entry >= compat_sc_table.table |
| 1476 | && entry < compat_sc_table.table + compat_sc_table.len)) { |
| 1477 | return -EINVAL; |
| 1478 | } |
| 1479 | if (bitness) |
| 1480 | *bitness = 32; |
| 1481 | if (table) |
| 1482 | *table = compat_sc_table.table; |
| 1483 | return 0; |
| 1484 | } |
| 1485 | |
| 1486 | static |
| 1487 | int syscall_list_show(struct seq_file *m, void *p) |
| 1488 | { |
| 1489 | const struct trace_syscall_entry *table, *entry = p; |
| 1490 | unsigned int bitness; |
| 1491 | unsigned long index; |
| 1492 | int ret; |
| 1493 | const char *name; |
| 1494 | |
| 1495 | ret = get_sc_table(entry, &table, &bitness); |
| 1496 | if (ret) |
| 1497 | return ret; |
| 1498 | if (!entry->desc) |
| 1499 | return 0; |
| 1500 | if (table == sc_table.table) { |
| 1501 | index = entry - table; |
| 1502 | name = &entry->desc->event_name[strlen(SYSCALL_ENTRY_STR)]; |
| 1503 | } else { |
| 1504 | index = (entry - table) + sc_table.len; |
| 1505 | name = &entry->desc->event_name[strlen(COMPAT_SYSCALL_ENTRY_STR)]; |
| 1506 | } |
| 1507 | seq_printf(m, "syscall { index = %lu; name = %s; bitness = %u; };\n", |
| 1508 | index, name, bitness); |
| 1509 | return 0; |
| 1510 | } |
| 1511 | |
| 1512 | static |
| 1513 | const struct seq_operations lttng_syscall_list_seq_ops = { |
| 1514 | .start = syscall_list_start, |
| 1515 | .next = syscall_list_next, |
| 1516 | .stop = syscall_list_stop, |
| 1517 | .show = syscall_list_show, |
| 1518 | }; |
| 1519 | |
| 1520 | static |
| 1521 | int lttng_syscall_list_open(struct inode *inode, struct file *file) |
| 1522 | { |
| 1523 | return seq_open(file, <tng_syscall_list_seq_ops); |
| 1524 | } |
| 1525 | |
| 1526 | const struct file_operations lttng_syscall_list_fops = { |
| 1527 | .owner = THIS_MODULE, |
| 1528 | .open = lttng_syscall_list_open, |
| 1529 | .read = seq_read, |
| 1530 | .llseek = seq_lseek, |
| 1531 | .release = seq_release, |
| 1532 | }; |
| 1533 | |
| 1534 | /* |
| 1535 | * A syscall is enabled if it is traced for either entry or exit. |
| 1536 | */ |
| 1537 | long lttng_syscall_table_get_active_mask(struct lttng_kernel_syscall_table *syscall_table, |
| 1538 | struct lttng_kernel_abi_syscall_mask __user *usyscall_mask) |
| 1539 | { |
| 1540 | uint32_t len, sc_tables_len, bitmask_len; |
| 1541 | int ret = 0, bit; |
| 1542 | char *tmp_mask; |
| 1543 | struct lttng_syscall_filter *filter; |
| 1544 | |
| 1545 | ret = get_user(len, &usyscall_mask->len); |
| 1546 | if (ret) |
| 1547 | return ret; |
| 1548 | sc_tables_len = get_sc_tables_len(); |
| 1549 | bitmask_len = ALIGN(sc_tables_len, 8) >> 3; |
| 1550 | if (len < sc_tables_len) { |
| 1551 | return put_user(sc_tables_len, &usyscall_mask->len); |
| 1552 | } |
| 1553 | /* Array is large enough, we can copy array to user-space. */ |
| 1554 | tmp_mask = kzalloc(bitmask_len, GFP_KERNEL); |
| 1555 | if (!tmp_mask) |
| 1556 | return -ENOMEM; |
| 1557 | filter = syscall_table->sc_filter; |
| 1558 | |
| 1559 | for (bit = 0; bit < sc_table.len; bit++) { |
| 1560 | char state; |
| 1561 | |
| 1562 | if (syscall_table->syscall_dispatch) { |
| 1563 | if (!(READ_ONCE(syscall_table->syscall_all_entry) |
| 1564 | || READ_ONCE(syscall_table->syscall_all_exit)) && filter) |
| 1565 | state = test_bit(bit, filter->sc_entry) |
| 1566 | || test_bit(bit, filter->sc_exit); |
| 1567 | else |
| 1568 | state = 1; |
| 1569 | } else { |
| 1570 | state = 0; |
| 1571 | } |
| 1572 | bt_bitfield_write_be(tmp_mask, char, bit, 1, state); |
| 1573 | } |
| 1574 | for (; bit < sc_tables_len; bit++) { |
| 1575 | char state; |
| 1576 | |
| 1577 | if (syscall_table->compat_syscall_dispatch) { |
| 1578 | if (!(READ_ONCE(syscall_table->syscall_all_entry) |
| 1579 | || READ_ONCE(syscall_table->syscall_all_exit)) && filter) |
| 1580 | state = test_bit(bit - sc_table.len, |
| 1581 | filter->sc_compat_entry) |
| 1582 | || test_bit(bit - sc_table.len, |
| 1583 | filter->sc_compat_exit); |
| 1584 | else |
| 1585 | state = 1; |
| 1586 | } else { |
| 1587 | state = 0; |
| 1588 | } |
| 1589 | bt_bitfield_write_be(tmp_mask, char, bit, 1, state); |
| 1590 | } |
| 1591 | if (copy_to_user(usyscall_mask->mask, tmp_mask, bitmask_len)) |
| 1592 | ret = -EFAULT; |
| 1593 | kfree(tmp_mask); |
| 1594 | return ret; |
| 1595 | } |
| 1596 | |
| 1597 | int lttng_abi_syscall_list(void) |
| 1598 | { |
| 1599 | struct file *syscall_list_file; |
| 1600 | int file_fd, ret; |
| 1601 | |
| 1602 | file_fd = lttng_get_unused_fd(); |
| 1603 | if (file_fd < 0) { |
| 1604 | ret = file_fd; |
| 1605 | goto fd_error; |
| 1606 | } |
| 1607 | |
| 1608 | syscall_list_file = anon_inode_getfile("[lttng_syscall_list]", |
| 1609 | <tng_syscall_list_fops, |
| 1610 | NULL, O_RDWR); |
| 1611 | if (IS_ERR(syscall_list_file)) { |
| 1612 | ret = PTR_ERR(syscall_list_file); |
| 1613 | goto file_error; |
| 1614 | } |
| 1615 | ret = lttng_syscall_list_fops.open(NULL, syscall_list_file); |
| 1616 | if (ret < 0) |
| 1617 | goto open_error; |
| 1618 | fd_install(file_fd, syscall_list_file); |
| 1619 | return file_fd; |
| 1620 | |
| 1621 | open_error: |
| 1622 | fput(syscall_list_file); |
| 1623 | file_error: |
| 1624 | put_unused_fd(file_fd); |
| 1625 | fd_error: |
| 1626 | return ret; |
| 1627 | } |