| 1 | /* |
| 2 | * SPDX-License-Identifier: LGPL-2.1-only |
| 3 | * |
| 4 | * Copyright (C) 2009 Pierre-Marc Fournier |
| 5 | * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 6 | */ |
| 7 | |
| 8 | /* Has to be included first to override dlfcn.h */ |
| 9 | #include <common/compat/dlfcn.h> |
| 10 | |
| 11 | #include <unistd.h> |
| 12 | #include <stdio.h> |
| 13 | #include <signal.h> |
| 14 | #include <sched.h> |
| 15 | #include <stdarg.h> |
| 16 | #include <stdlib.h> |
| 17 | #include <errno.h> |
| 18 | |
| 19 | #include <lttng/ust-fork.h> |
| 20 | |
| 21 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 22 | static int (*__ust_before_fork)(sigset_t *save_sigset) = NULL; |
| 23 | static int (*__ust_after_fork_child)(sigset_t *restore_sigset) = NULL; |
| 24 | static int (*__ust_after_fork_parent)(sigset_t *restore_sigset) = NULL; |
| 25 | |
| 26 | static void (*__ust_after_setns)(void) = NULL; |
| 27 | static void (*__ust_after_unshare)(void) = NULL; |
| 28 | static void (*__ust_after_setuid)(void) = NULL; |
| 29 | static void (*__ust_after_setgid)(void) = NULL; |
| 30 | static void (*__ust_after_seteuid)(void) = NULL; |
| 31 | static void (*__ust_after_setegid)(void) = NULL; |
| 32 | static void (*__ust_after_setreuid)(void) = NULL; |
| 33 | static void (*__ust_after_setregid)(void) = NULL; |
| 34 | static void (*__ust_after_setresuid)(void) = NULL; |
| 35 | static void (*__ust_after_setresgid)(void) = NULL; |
| 36 | |
| 37 | static |
| 38 | void *_init_ust_before_fork(void) |
| 39 | { |
| 40 | if (__ust_before_fork == NULL) { |
| 41 | __ust_before_fork = dlsym(RTLD_DEFAULT, "ust_before_fork"); |
| 42 | |
| 43 | if (__ust_before_fork == NULL) { |
| 44 | fprintf(stderr, "%s\n", dlerror()); |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | return __ust_before_fork; |
| 49 | } |
| 50 | |
| 51 | static |
| 52 | void *_init_ust_after_fork_child(void) |
| 53 | { |
| 54 | if (__ust_after_fork_child == NULL) { |
| 55 | __ust_after_fork_child = dlsym(RTLD_DEFAULT, "ust_after_fork_child"); |
| 56 | |
| 57 | if (__ust_after_fork_child == NULL) { |
| 58 | fprintf(stderr, "%s\n", dlerror()); |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | return __ust_after_fork_child; |
| 63 | } |
| 64 | |
| 65 | static |
| 66 | void *_init_ust_after_fork_parent(void) |
| 67 | { |
| 68 | if (__ust_after_fork_parent == NULL) { |
| 69 | __ust_after_fork_parent = dlsym(RTLD_DEFAULT, "ust_after_fork_parent"); |
| 70 | |
| 71 | if (__ust_after_fork_parent == NULL) { |
| 72 | fprintf(stderr, "%s\n", dlerror()); |
| 73 | } |
| 74 | } |
| 75 | |
| 76 | return __ust_after_fork_parent; |
| 77 | } |
| 78 | |
| 79 | static |
| 80 | void *_init_ust_after_setns(void) |
| 81 | { |
| 82 | if (__ust_after_setns == NULL) { |
| 83 | __ust_after_setns = dlsym(RTLD_DEFAULT, "ust_after_setns"); |
| 84 | |
| 85 | if (__ust_after_setns == NULL) { |
| 86 | fprintf(stderr, "%s\n", dlerror()); |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | return __ust_after_setns; |
| 91 | } |
| 92 | |
| 93 | static |
| 94 | void *_init_ust_after_unshare(void) |
| 95 | { |
| 96 | if (__ust_after_unshare == NULL) { |
| 97 | __ust_after_unshare = dlsym(RTLD_DEFAULT, "ust_after_unshare"); |
| 98 | |
| 99 | if (__ust_after_unshare == NULL) { |
| 100 | fprintf(stderr, "%s\n", dlerror()); |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | return __ust_after_unshare; |
| 105 | } |
| 106 | |
| 107 | static |
| 108 | void *_init_ust_after_setuid(void) |
| 109 | { |
| 110 | if (__ust_after_setuid == NULL) { |
| 111 | __ust_after_setuid = dlsym(RTLD_DEFAULT, "ust_after_setuid"); |
| 112 | |
| 113 | if (__ust_after_setuid == NULL) { |
| 114 | fprintf(stderr, "%s\n", dlerror()); |
| 115 | } |
| 116 | } |
| 117 | |
| 118 | return __ust_after_setuid; |
| 119 | } |
| 120 | |
| 121 | static |
| 122 | void *_init_ust_after_setgid(void) |
| 123 | { |
| 124 | if (__ust_after_setgid == NULL) { |
| 125 | __ust_after_setgid = dlsym(RTLD_DEFAULT, "ust_after_setgid"); |
| 126 | |
| 127 | if (__ust_after_setgid == NULL) { |
| 128 | fprintf(stderr, "%s\n", dlerror()); |
| 129 | } |
| 130 | } |
| 131 | |
| 132 | return __ust_after_setgid; |
| 133 | } |
| 134 | |
| 135 | static |
| 136 | void *_init_ust_after_seteuid(void) |
| 137 | { |
| 138 | if (__ust_after_seteuid == NULL) { |
| 139 | __ust_after_seteuid = dlsym(RTLD_DEFAULT, "ust_after_seteuid"); |
| 140 | |
| 141 | if (__ust_after_seteuid == NULL) { |
| 142 | fprintf(stderr, "%s\n", dlerror()); |
| 143 | } |
| 144 | } |
| 145 | |
| 146 | return __ust_after_seteuid; |
| 147 | } |
| 148 | |
| 149 | static |
| 150 | void *_init_ust_after_setegid(void) |
| 151 | { |
| 152 | if (__ust_after_setegid == NULL) { |
| 153 | __ust_after_setegid = dlsym(RTLD_DEFAULT, "ust_after_setegid"); |
| 154 | |
| 155 | if (__ust_after_setegid == NULL) { |
| 156 | fprintf(stderr, "%s\n", dlerror()); |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | return __ust_after_setegid; |
| 161 | } |
| 162 | |
| 163 | static |
| 164 | void *_init_ust_after_setreuid(void) |
| 165 | { |
| 166 | if (__ust_after_setreuid == NULL) { |
| 167 | __ust_after_setreuid = dlsym(RTLD_DEFAULT, "ust_after_setreuid"); |
| 168 | |
| 169 | if (__ust_after_setreuid == NULL) { |
| 170 | fprintf(stderr, "%s\n", dlerror()); |
| 171 | } |
| 172 | } |
| 173 | |
| 174 | return __ust_after_setreuid; |
| 175 | } |
| 176 | |
| 177 | static |
| 178 | void *_init_ust_after_setregid(void) |
| 179 | { |
| 180 | if (__ust_after_setregid == NULL) { |
| 181 | __ust_after_setregid = dlsym(RTLD_DEFAULT, "ust_after_setregid"); |
| 182 | |
| 183 | if (__ust_after_setregid == NULL) { |
| 184 | fprintf(stderr, "%s\n", dlerror()); |
| 185 | } |
| 186 | } |
| 187 | |
| 188 | return __ust_after_setregid; |
| 189 | } |
| 190 | |
| 191 | static |
| 192 | void *_init_ust_after_setresuid(void) |
| 193 | { |
| 194 | if (__ust_after_setresuid == NULL) { |
| 195 | __ust_after_setresuid = dlsym(RTLD_DEFAULT, "ust_after_setresuid"); |
| 196 | |
| 197 | if (__ust_after_setresuid == NULL) { |
| 198 | fprintf(stderr, "%s\n", dlerror()); |
| 199 | } |
| 200 | } |
| 201 | |
| 202 | return __ust_after_setresuid; |
| 203 | } |
| 204 | |
| 205 | static |
| 206 | void *_init_ust_after_setresgid(void) |
| 207 | { |
| 208 | if (__ust_after_setresgid == NULL) { |
| 209 | __ust_after_setresgid = dlsym(RTLD_DEFAULT, "ust_after_setresgid"); |
| 210 | |
| 211 | if (__ust_after_setresgid == NULL) { |
| 212 | fprintf(stderr, "%s\n", dlerror()); |
| 213 | } |
| 214 | } |
| 215 | |
| 216 | return __ust_after_setresgid; |
| 217 | } |
| 218 | |
| 219 | static |
| 220 | void _lttng_ust_fork_ctor(void) |
| 221 | __attribute__((constructor)); |
| 222 | static |
| 223 | void _lttng_ust_fork_ctor(void) |
| 224 | { |
| 225 | void *handle = NULL; |
| 226 | |
| 227 | /* |
| 228 | * Load ust-2.12 in the global symbol namespace. |
| 229 | */ |
| 230 | handle = dlopen("liblttng-ust.so.0", RTLD_GLOBAL | RTLD_NOW); |
| 231 | if (!handle) { |
| 232 | fprintf(stderr, "liblttng-ust-fork.so.1: Failed to dlopen liblttng-ust.so.0: %s\n", dlerror()); |
| 233 | abort(); |
| 234 | } |
| 235 | } |
| 236 | #endif |
| 237 | |
| 238 | pid_t fork(void) |
| 239 | { |
| 240 | static pid_t (*plibc_func)(void) = NULL; |
| 241 | sigset_t sigset; |
| 242 | pid_t retval; |
| 243 | int saved_errno; |
| 244 | |
| 245 | if (plibc_func == NULL) { |
| 246 | plibc_func = dlsym(RTLD_NEXT, "fork"); |
| 247 | if (plibc_func == NULL) { |
| 248 | fprintf(stderr, "libustfork: unable to find \"fork\" symbol\n"); |
| 249 | errno = ENOSYS; |
| 250 | return -1; |
| 251 | } |
| 252 | } |
| 253 | |
| 254 | lttng_ust_before_fork(&sigset); |
| 255 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 256 | if (_init_ust_before_fork()) { |
| 257 | __ust_before_fork(&sigset); |
| 258 | } |
| 259 | #endif |
| 260 | |
| 261 | /* Do the real fork */ |
| 262 | retval = plibc_func(); |
| 263 | saved_errno = errno; |
| 264 | if (retval == 0) { |
| 265 | /* child */ |
| 266 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 267 | if (_init_ust_after_fork_child()) { |
| 268 | __ust_after_fork_child(&sigset); |
| 269 | } |
| 270 | #endif |
| 271 | lttng_ust_after_fork_child(&sigset); |
| 272 | } else { |
| 273 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 274 | if (_init_ust_after_fork_parent()) { |
| 275 | __ust_after_fork_parent(&sigset); |
| 276 | } |
| 277 | #endif |
| 278 | lttng_ust_after_fork_parent(&sigset); |
| 279 | } |
| 280 | errno = saved_errno; |
| 281 | return retval; |
| 282 | } |
| 283 | |
| 284 | int daemon(int nochdir, int noclose) |
| 285 | { |
| 286 | static int (*plibc_func)(int nochdir, int noclose) = NULL; |
| 287 | sigset_t sigset; |
| 288 | int retval; |
| 289 | int saved_errno; |
| 290 | |
| 291 | if (plibc_func == NULL) { |
| 292 | plibc_func = dlsym(RTLD_NEXT, "daemon"); |
| 293 | if (plibc_func == NULL) { |
| 294 | fprintf(stderr, "libustfork: unable to find \"daemon\" symbol\n"); |
| 295 | errno = ENOSYS; |
| 296 | return -1; |
| 297 | } |
| 298 | } |
| 299 | |
| 300 | lttng_ust_before_fork(&sigset); |
| 301 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 302 | if (_init_ust_before_fork()) { |
| 303 | __ust_before_fork(&sigset); |
| 304 | } |
| 305 | #endif |
| 306 | |
| 307 | /* Do the real daemon call */ |
| 308 | retval = plibc_func(nochdir, noclose); |
| 309 | saved_errno = errno; |
| 310 | if (retval == 0) { |
| 311 | /* child, parent called _exit() directly */ |
| 312 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 313 | if (_init_ust_after_fork_child()) { |
| 314 | __ust_after_fork_child(&sigset); |
| 315 | } |
| 316 | #endif |
| 317 | lttng_ust_after_fork_child(&sigset); |
| 318 | } else { |
| 319 | /* on error in the parent */ |
| 320 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 321 | if (_init_ust_after_fork_parent()) { |
| 322 | __ust_after_fork_parent(&sigset); |
| 323 | } |
| 324 | #endif |
| 325 | lttng_ust_after_fork_parent(&sigset); |
| 326 | } |
| 327 | errno = saved_errno; |
| 328 | return retval; |
| 329 | } |
| 330 | |
| 331 | int setuid(uid_t uid) |
| 332 | { |
| 333 | static int (*plibc_func)(uid_t uid) = NULL; |
| 334 | int retval; |
| 335 | int saved_errno; |
| 336 | |
| 337 | if (plibc_func == NULL) { |
| 338 | plibc_func = dlsym(RTLD_NEXT, "setuid"); |
| 339 | if (plibc_func == NULL) { |
| 340 | fprintf(stderr, "libustfork: unable to find \"setuid\" symbol\n"); |
| 341 | errno = ENOSYS; |
| 342 | return -1; |
| 343 | } |
| 344 | } |
| 345 | |
| 346 | /* Do the real setuid */ |
| 347 | retval = plibc_func(uid); |
| 348 | saved_errno = errno; |
| 349 | |
| 350 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 351 | if (_init_ust_after_setuid()) { |
| 352 | __ust_after_setuid(); |
| 353 | } |
| 354 | #endif |
| 355 | lttng_ust_after_setuid(); |
| 356 | |
| 357 | errno = saved_errno; |
| 358 | return retval; |
| 359 | } |
| 360 | |
| 361 | int setgid(gid_t gid) |
| 362 | { |
| 363 | static int (*plibc_func)(gid_t gid) = NULL; |
| 364 | int retval; |
| 365 | int saved_errno; |
| 366 | |
| 367 | if (plibc_func == NULL) { |
| 368 | plibc_func = dlsym(RTLD_NEXT, "setgid"); |
| 369 | if (plibc_func == NULL) { |
| 370 | fprintf(stderr, "libustfork: unable to find \"setgid\" symbol\n"); |
| 371 | errno = ENOSYS; |
| 372 | return -1; |
| 373 | } |
| 374 | } |
| 375 | |
| 376 | /* Do the real setgid */ |
| 377 | retval = plibc_func(gid); |
| 378 | saved_errno = errno; |
| 379 | |
| 380 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 381 | if (_init_ust_after_setgid()) { |
| 382 | __ust_after_setgid(); |
| 383 | } |
| 384 | #endif |
| 385 | lttng_ust_after_setgid(); |
| 386 | |
| 387 | errno = saved_errno; |
| 388 | return retval; |
| 389 | } |
| 390 | |
| 391 | int seteuid(uid_t euid) |
| 392 | { |
| 393 | static int (*plibc_func)(uid_t euid) = NULL; |
| 394 | int retval; |
| 395 | int saved_errno; |
| 396 | |
| 397 | if (plibc_func == NULL) { |
| 398 | plibc_func = dlsym(RTLD_NEXT, "seteuid"); |
| 399 | if (plibc_func == NULL) { |
| 400 | fprintf(stderr, "libustfork: unable to find \"seteuid\" symbol\n"); |
| 401 | errno = ENOSYS; |
| 402 | return -1; |
| 403 | } |
| 404 | } |
| 405 | |
| 406 | /* Do the real seteuid */ |
| 407 | retval = plibc_func(euid); |
| 408 | saved_errno = errno; |
| 409 | |
| 410 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 411 | if (_init_ust_after_seteuid()) { |
| 412 | __ust_after_seteuid(); |
| 413 | } |
| 414 | #endif |
| 415 | lttng_ust_after_seteuid(); |
| 416 | |
| 417 | errno = saved_errno; |
| 418 | return retval; |
| 419 | } |
| 420 | |
| 421 | int setegid(gid_t egid) |
| 422 | { |
| 423 | static int (*plibc_func)(gid_t egid) = NULL; |
| 424 | int retval; |
| 425 | int saved_errno; |
| 426 | |
| 427 | if (plibc_func == NULL) { |
| 428 | plibc_func = dlsym(RTLD_NEXT, "setegid"); |
| 429 | if (plibc_func == NULL) { |
| 430 | fprintf(stderr, "libustfork: unable to find \"setegid\" symbol\n"); |
| 431 | errno = ENOSYS; |
| 432 | return -1; |
| 433 | } |
| 434 | } |
| 435 | |
| 436 | /* Do the real setegid */ |
| 437 | retval = plibc_func(egid); |
| 438 | saved_errno = errno; |
| 439 | |
| 440 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 441 | if (_init_ust_after_setegid()) { |
| 442 | __ust_after_setegid(); |
| 443 | } |
| 444 | #endif |
| 445 | lttng_ust_after_setegid(); |
| 446 | |
| 447 | errno = saved_errno; |
| 448 | return retval; |
| 449 | } |
| 450 | |
| 451 | int setreuid(uid_t ruid, uid_t euid) |
| 452 | { |
| 453 | static int (*plibc_func)(uid_t ruid, uid_t euid) = NULL; |
| 454 | int retval; |
| 455 | int saved_errno; |
| 456 | |
| 457 | if (plibc_func == NULL) { |
| 458 | plibc_func = dlsym(RTLD_NEXT, "setreuid"); |
| 459 | if (plibc_func == NULL) { |
| 460 | fprintf(stderr, "libustfork: unable to find \"setreuid\" symbol\n"); |
| 461 | errno = ENOSYS; |
| 462 | return -1; |
| 463 | } |
| 464 | } |
| 465 | |
| 466 | /* Do the real setreuid */ |
| 467 | retval = plibc_func(ruid, euid); |
| 468 | saved_errno = errno; |
| 469 | |
| 470 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 471 | if (_init_ust_after_setreuid()) { |
| 472 | __ust_after_setreuid(); |
| 473 | } |
| 474 | #endif |
| 475 | lttng_ust_after_setreuid(); |
| 476 | |
| 477 | errno = saved_errno; |
| 478 | return retval; |
| 479 | } |
| 480 | |
| 481 | int setregid(gid_t rgid, gid_t egid) |
| 482 | { |
| 483 | static int (*plibc_func)(gid_t rgid, gid_t egid) = NULL; |
| 484 | int retval; |
| 485 | int saved_errno; |
| 486 | |
| 487 | if (plibc_func == NULL) { |
| 488 | plibc_func = dlsym(RTLD_NEXT, "setregid"); |
| 489 | if (plibc_func == NULL) { |
| 490 | fprintf(stderr, "libustfork: unable to find \"setregid\" symbol\n"); |
| 491 | errno = ENOSYS; |
| 492 | return -1; |
| 493 | } |
| 494 | } |
| 495 | |
| 496 | /* Do the real setregid */ |
| 497 | retval = plibc_func(rgid, egid); |
| 498 | saved_errno = errno; |
| 499 | |
| 500 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 501 | if (_init_ust_after_setregid()) { |
| 502 | __ust_after_setregid(); |
| 503 | } |
| 504 | #endif |
| 505 | lttng_ust_after_setregid(); |
| 506 | |
| 507 | errno = saved_errno; |
| 508 | return retval; |
| 509 | } |
| 510 | |
| 511 | #ifdef __linux__ |
| 512 | |
| 513 | struct user_desc; |
| 514 | |
| 515 | struct ustfork_clone_info { |
| 516 | int (*fn)(void *); |
| 517 | void *arg; |
| 518 | sigset_t sigset; |
| 519 | }; |
| 520 | |
| 521 | static int clone_fn(void *arg) |
| 522 | { |
| 523 | struct ustfork_clone_info *info = (struct ustfork_clone_info *) arg; |
| 524 | |
| 525 | /* clone is now done and we are in child */ |
| 526 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 527 | if (_init_ust_after_fork_child()) { |
| 528 | __ust_after_fork_child(&info->sigset); |
| 529 | } |
| 530 | #endif |
| 531 | lttng_ust_after_fork_child(&info->sigset); |
| 532 | return info->fn(info->arg); |
| 533 | } |
| 534 | |
| 535 | int clone(int (*fn)(void *), void *child_stack, int flags, void *arg, ...) |
| 536 | { |
| 537 | static int (*plibc_func)(int (*fn)(void *), void *child_stack, |
| 538 | int flags, void *arg, pid_t *ptid, |
| 539 | struct user_desc *tls, pid_t *ctid) = NULL; |
| 540 | /* var args */ |
| 541 | pid_t *ptid; |
| 542 | struct user_desc *tls; |
| 543 | pid_t *ctid; |
| 544 | /* end of var args */ |
| 545 | va_list ap; |
| 546 | int retval; |
| 547 | int saved_errno; |
| 548 | |
| 549 | va_start(ap, arg); |
| 550 | ptid = va_arg(ap, pid_t *); |
| 551 | tls = va_arg(ap, struct user_desc *); |
| 552 | ctid = va_arg(ap, pid_t *); |
| 553 | va_end(ap); |
| 554 | |
| 555 | if (plibc_func == NULL) { |
| 556 | plibc_func = dlsym(RTLD_NEXT, "clone"); |
| 557 | if (plibc_func == NULL) { |
| 558 | fprintf(stderr, "libustfork: unable to find \"clone\" symbol.\n"); |
| 559 | errno = ENOSYS; |
| 560 | return -1; |
| 561 | } |
| 562 | } |
| 563 | |
| 564 | if (flags & CLONE_VM) { |
| 565 | /* |
| 566 | * Creating a thread, no need to intervene, just pass on |
| 567 | * the arguments. |
| 568 | */ |
| 569 | retval = plibc_func(fn, child_stack, flags, arg, ptid, |
| 570 | tls, ctid); |
| 571 | saved_errno = errno; |
| 572 | } else { |
| 573 | /* Creating a real process, we need to intervene. */ |
| 574 | struct ustfork_clone_info info = { .fn = fn, .arg = arg }; |
| 575 | |
| 576 | lttng_ust_before_fork(&info.sigset); |
| 577 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 578 | if (_init_ust_before_fork()) { |
| 579 | __ust_before_fork(&info.sigset); |
| 580 | } |
| 581 | #endif |
| 582 | retval = plibc_func(clone_fn, child_stack, flags, &info, |
| 583 | ptid, tls, ctid); |
| 584 | saved_errno = errno; |
| 585 | /* The child doesn't get here. */ |
| 586 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 587 | if (_init_ust_after_fork_parent()) { |
| 588 | __ust_after_fork_parent(&info.sigset); |
| 589 | } |
| 590 | #endif |
| 591 | lttng_ust_after_fork_parent(&info.sigset); |
| 592 | } |
| 593 | errno = saved_errno; |
| 594 | return retval; |
| 595 | } |
| 596 | |
| 597 | int setns(int fd, int nstype) |
| 598 | { |
| 599 | static int (*plibc_func)(int fd, int nstype) = NULL; |
| 600 | int retval; |
| 601 | int saved_errno; |
| 602 | |
| 603 | if (plibc_func == NULL) { |
| 604 | plibc_func = dlsym(RTLD_NEXT, "setns"); |
| 605 | if (plibc_func == NULL) { |
| 606 | fprintf(stderr, "libustfork: unable to find \"setns\" symbol\n"); |
| 607 | errno = ENOSYS; |
| 608 | return -1; |
| 609 | } |
| 610 | } |
| 611 | |
| 612 | /* Do the real setns */ |
| 613 | retval = plibc_func(fd, nstype); |
| 614 | saved_errno = errno; |
| 615 | |
| 616 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 617 | if (_init_ust_after_setns()) { |
| 618 | __ust_after_setns(); |
| 619 | } |
| 620 | #endif |
| 621 | lttng_ust_after_setns(); |
| 622 | |
| 623 | errno = saved_errno; |
| 624 | return retval; |
| 625 | } |
| 626 | |
| 627 | int unshare(int flags) |
| 628 | { |
| 629 | static int (*plibc_func)(int flags) = NULL; |
| 630 | int retval; |
| 631 | int saved_errno; |
| 632 | |
| 633 | if (plibc_func == NULL) { |
| 634 | plibc_func = dlsym(RTLD_NEXT, "unshare"); |
| 635 | if (plibc_func == NULL) { |
| 636 | fprintf(stderr, "libustfork: unable to find \"unshare\" symbol\n"); |
| 637 | errno = ENOSYS; |
| 638 | return -1; |
| 639 | } |
| 640 | } |
| 641 | |
| 642 | /* Do the real setns */ |
| 643 | retval = plibc_func(flags); |
| 644 | saved_errno = errno; |
| 645 | |
| 646 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 647 | if (_init_ust_after_unshare()) { |
| 648 | __ust_after_unshare(); |
| 649 | } |
| 650 | #endif |
| 651 | lttng_ust_after_unshare(); |
| 652 | |
| 653 | errno = saved_errno; |
| 654 | return retval; |
| 655 | } |
| 656 | |
| 657 | int setresuid(uid_t ruid, uid_t euid, uid_t suid) |
| 658 | { |
| 659 | static int (*plibc_func)(uid_t ruid, uid_t euid, uid_t suid) = NULL; |
| 660 | int retval; |
| 661 | int saved_errno; |
| 662 | |
| 663 | if (plibc_func == NULL) { |
| 664 | plibc_func = dlsym(RTLD_NEXT, "setresuid"); |
| 665 | if (plibc_func == NULL) { |
| 666 | fprintf(stderr, "libustfork: unable to find \"setresuid\" symbol\n"); |
| 667 | errno = ENOSYS; |
| 668 | return -1; |
| 669 | } |
| 670 | } |
| 671 | |
| 672 | /* Do the real setresuid */ |
| 673 | retval = plibc_func(ruid, euid, suid); |
| 674 | saved_errno = errno; |
| 675 | |
| 676 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 677 | if (_init_ust_after_setresuid()) { |
| 678 | __ust_after_setresuid(); |
| 679 | } |
| 680 | #endif |
| 681 | lttng_ust_after_setresuid(); |
| 682 | |
| 683 | errno = saved_errno; |
| 684 | return retval; |
| 685 | } |
| 686 | |
| 687 | int setresgid(gid_t rgid, gid_t egid, gid_t sgid) |
| 688 | { |
| 689 | static int (*plibc_func)(gid_t rgid, gid_t egid, gid_t sgid) = NULL; |
| 690 | int retval; |
| 691 | int saved_errno; |
| 692 | |
| 693 | if (plibc_func == NULL) { |
| 694 | plibc_func = dlsym(RTLD_NEXT, "setresgid"); |
| 695 | if (plibc_func == NULL) { |
| 696 | fprintf(stderr, "libustfork: unable to find \"setresgid\" symbol\n"); |
| 697 | errno = ENOSYS; |
| 698 | return -1; |
| 699 | } |
| 700 | } |
| 701 | |
| 702 | /* Do the real setresgid */ |
| 703 | retval = plibc_func(rgid, egid, sgid); |
| 704 | saved_errno = errno; |
| 705 | |
| 706 | #if !defined(LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS) |
| 707 | if (_init_ust_after_setresgid()) { |
| 708 | __ust_after_setresgid(); |
| 709 | } |
| 710 | #endif |
| 711 | lttng_ust_after_setresgid(); |
| 712 | |
| 713 | errno = saved_errno; |
| 714 | return retval; |
| 715 | } |
| 716 | |
| 717 | #elif defined (__FreeBSD__) |
| 718 | |
| 719 | pid_t rfork(int flags) |
| 720 | { |
| 721 | static pid_t (*plibc_func)(int flags) = NULL; |
| 722 | sigset_t sigset; |
| 723 | pid_t retval; |
| 724 | int saved_errno; |
| 725 | |
| 726 | if (plibc_func == NULL) { |
| 727 | plibc_func = dlsym(RTLD_NEXT, "rfork"); |
| 728 | if (plibc_func == NULL) { |
| 729 | fprintf(stderr, "libustfork: unable to find \"rfork\" symbol\n"); |
| 730 | errno = ENOSYS; |
| 731 | return -1; |
| 732 | } |
| 733 | } |
| 734 | |
| 735 | lttng_ust_before_fork(&sigset); |
| 736 | /* Do the real rfork */ |
| 737 | retval = plibc_func(flags); |
| 738 | saved_errno = errno; |
| 739 | if (retval == 0) { |
| 740 | /* child */ |
| 741 | lttng_ust_after_fork_child(&sigset); |
| 742 | } else { |
| 743 | lttng_ust_after_fork_parent(&sigset); |
| 744 | } |
| 745 | errno = saved_errno; |
| 746 | return retval; |
| 747 | } |
| 748 | |
| 749 | /* |
| 750 | * On BSD, no need to override vfork, because it runs in the context of |
| 751 | * the parent, with parent waiting until execve or exit is executed in |
| 752 | * the child. |
| 753 | */ |
| 754 | |
| 755 | #else |
| 756 | #warning "Unknown OS. You might want to ensure that fork/clone/vfork/fork handling is complete." |
| 757 | #endif |