1 //===-- sanitizer_linux.cpp -----------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file is shared between AddressSanitizer and ThreadSanitizer 10 // run-time libraries and implements linux-specific functions from 11 // sanitizer_libc.h. 12 //===----------------------------------------------------------------------===// 13 14 #include "sanitizer_platform.h" 15 16 #if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \ 17 SANITIZER_SOLARIS 18 19 #include "sanitizer_common.h" 20 #include "sanitizer_flags.h" 21 #include "sanitizer_getauxval.h" 22 #include "sanitizer_internal_defs.h" 23 #include "sanitizer_libc.h" 24 #include "sanitizer_linux.h" 25 #include "sanitizer_mutex.h" 26 #include "sanitizer_placement_new.h" 27 #include "sanitizer_procmaps.h" 28 29 #if SANITIZER_LINUX && !SANITIZER_GO 30 #include <asm/param.h> 31 #endif 32 33 // For mips64, syscall(__NR_stat) fills the buffer in the 'struct kernel_stat' 34 // format. Struct kernel_stat is defined as 'struct stat' in asm/stat.h. To 35 // access stat from asm/stat.h, without conflicting with definition in 36 // sys/stat.h, we use this trick. 37 #if defined(__mips64) 38 #include <asm/unistd.h> 39 #include <sys/types.h> 40 #define stat kernel_stat 41 #if SANITIZER_GO 42 #undef st_atime 43 #undef st_mtime 44 #undef st_ctime 45 #define st_atime st_atim 46 #define st_mtime st_mtim 47 #define st_ctime st_ctim 48 #endif 49 #include <asm/stat.h> 50 #undef stat 51 #endif 52 53 #include <dlfcn.h> 54 #include <errno.h> 55 #include <fcntl.h> 56 #include <link.h> 57 #include <pthread.h> 58 #include <sched.h> 59 #include <signal.h> 60 #include <sys/mman.h> 61 #include <sys/param.h> 62 #if !SANITIZER_SOLARIS 63 #include <sys/ptrace.h> 64 #endif 65 #include <sys/resource.h> 66 #include <sys/stat.h> 67 #include <sys/syscall.h> 68 #include <sys/time.h> 69 #include <sys/types.h> 70 #include <ucontext.h> 71 #include <unistd.h> 72 73 #if SANITIZER_LINUX 74 #include <sys/utsname.h> 75 #endif 76 77 #if SANITIZER_LINUX && !SANITIZER_ANDROID 78 #include <sys/personality.h> 79 #endif 80 81 #if SANITIZER_FREEBSD 82 #include <sys/exec.h> 83 #include <sys/sysctl.h> 84 #include <machine/atomic.h> 85 extern "C" { 86 // <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on 87 // FreeBSD 9.2 and 10.0. 88 #include <sys/umtx.h> 89 } 90 #include <sys/thr.h> 91 #endif // SANITIZER_FREEBSD 92 93 #if SANITIZER_NETBSD 94 #include <limits.h> // For NAME_MAX 95 #include <sys/sysctl.h> 96 #include <sys/exec.h> 97 extern struct ps_strings *__ps_strings; 98 #endif // SANITIZER_NETBSD 99 100 #if SANITIZER_SOLARIS 101 #include <stdlib.h> 102 #include <thread.h> 103 #define environ _environ 104 #endif 105 106 extern char **environ; 107 108 #if SANITIZER_LINUX 109 // <linux/time.h> 110 struct kernel_timeval { 111 long tv_sec; 112 long tv_usec; 113 }; 114 115 // <linux/futex.h> is broken on some linux distributions. 116 const int FUTEX_WAIT = 0; 117 const int FUTEX_WAKE = 1; 118 const int FUTEX_PRIVATE_FLAG = 128; 119 const int FUTEX_WAIT_PRIVATE = FUTEX_WAIT | FUTEX_PRIVATE_FLAG; 120 const int FUTEX_WAKE_PRIVATE = FUTEX_WAKE | FUTEX_PRIVATE_FLAG; 121 #endif // SANITIZER_LINUX 122 123 // Are we using 32-bit or 64-bit Linux syscalls? 124 // x32 (which defines __x86_64__) has SANITIZER_WORDSIZE == 32 125 // but it still needs to use 64-bit syscalls. 126 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__powerpc64__) || \ 127 SANITIZER_WORDSIZE == 64) 128 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 1 129 #else 130 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 0 131 #endif 132 133 // Note : FreeBSD had implemented both 134 // Linux apis, available from 135 // future 12.x version most likely 136 #if SANITIZER_LINUX && defined(__NR_getrandom) 137 # if !defined(GRND_NONBLOCK) 138 # define GRND_NONBLOCK 1 139 # endif 140 # define SANITIZER_USE_GETRANDOM 1 141 #else 142 # define SANITIZER_USE_GETRANDOM 0 143 #endif // SANITIZER_LINUX && defined(__NR_getrandom) 144 145 #if SANITIZER_FREEBSD && __FreeBSD_version >= 1200000 146 # define SANITIZER_USE_GETENTROPY 1 147 #else 148 # define SANITIZER_USE_GETENTROPY 0 149 #endif 150 151 namespace __sanitizer { 152 153 #if SANITIZER_LINUX && defined(__x86_64__) 154 #include "sanitizer_syscall_linux_x86_64.inc" 155 #elif SANITIZER_LINUX && SANITIZER_RISCV64 156 #include "sanitizer_syscall_linux_riscv64.inc" 157 #elif SANITIZER_LINUX && defined(__aarch64__) 158 #include "sanitizer_syscall_linux_aarch64.inc" 159 #elif SANITIZER_LINUX && defined(__arm__) 160 #include "sanitizer_syscall_linux_arm.inc" 161 #else 162 #include "sanitizer_syscall_generic.inc" 163 #endif 164 165 // --------------- sanitizer_libc.h 166 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 167 #if !SANITIZER_S390 168 uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd, 169 u64 offset) { 170 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 171 return internal_syscall(SYSCALL(mmap), (uptr)addr, length, prot, flags, fd, 172 offset); 173 #else 174 // mmap2 specifies file offset in 4096-byte units. 175 CHECK(IsAligned(offset, 4096)); 176 return internal_syscall(SYSCALL(mmap2), addr, length, prot, flags, fd, 177 offset / 4096); 178 #endif 179 } 180 #endif // !SANITIZER_S390 181 182 uptr internal_munmap(void *addr, uptr length) { 183 return internal_syscall(SYSCALL(munmap), (uptr)addr, length); 184 } 185 186 int internal_mprotect(void *addr, uptr length, int prot) { 187 return internal_syscall(SYSCALL(mprotect), (uptr)addr, length, prot); 188 } 189 190 int internal_madvise(uptr addr, uptr length, int advice) { 191 return internal_syscall(SYSCALL(madvise), addr, length, advice); 192 } 193 194 uptr internal_close(fd_t fd) { 195 return internal_syscall(SYSCALL(close), fd); 196 } 197 198 uptr internal_open(const char *filename, int flags) { 199 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 200 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags); 201 #else 202 return internal_syscall(SYSCALL(open), (uptr)filename, flags); 203 #endif 204 } 205 206 uptr internal_open(const char *filename, int flags, u32 mode) { 207 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 208 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags, 209 mode); 210 #else 211 return internal_syscall(SYSCALL(open), (uptr)filename, flags, mode); 212 #endif 213 } 214 215 uptr internal_read(fd_t fd, void *buf, uptr count) { 216 sptr res; 217 HANDLE_EINTR(res, 218 (sptr)internal_syscall(SYSCALL(read), fd, (uptr)buf, count)); 219 return res; 220 } 221 222 uptr internal_write(fd_t fd, const void *buf, uptr count) { 223 sptr res; 224 HANDLE_EINTR(res, 225 (sptr)internal_syscall(SYSCALL(write), fd, (uptr)buf, count)); 226 return res; 227 } 228 229 uptr internal_ftruncate(fd_t fd, uptr size) { 230 sptr res; 231 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(ftruncate), fd, 232 (OFF_T)size)); 233 return res; 234 } 235 236 #if !SANITIZER_LINUX_USES_64BIT_SYSCALLS && SANITIZER_LINUX 237 static void stat64_to_stat(struct stat64 *in, struct stat *out) { 238 internal_memset(out, 0, sizeof(*out)); 239 out->st_dev = in->st_dev; 240 out->st_ino = in->st_ino; 241 out->st_mode = in->st_mode; 242 out->st_nlink = in->st_nlink; 243 out->st_uid = in->st_uid; 244 out->st_gid = in->st_gid; 245 out->st_rdev = in->st_rdev; 246 out->st_size = in->st_size; 247 out->st_blksize = in->st_blksize; 248 out->st_blocks = in->st_blocks; 249 out->st_atime = in->st_atime; 250 out->st_mtime = in->st_mtime; 251 out->st_ctime = in->st_ctime; 252 } 253 #endif 254 255 #if defined(__mips64) 256 // Undefine compatibility macros from <sys/stat.h> 257 // so that they would not clash with the kernel_stat 258 // st_[a|m|c]time fields 259 #if !SANITIZER_GO 260 #undef st_atime 261 #undef st_mtime 262 #undef st_ctime 263 #endif 264 #if defined(SANITIZER_ANDROID) 265 // Bionic sys/stat.h defines additional macros 266 // for compatibility with the old NDKs and 267 // they clash with the kernel_stat structure 268 // st_[a|m|c]time_nsec fields. 269 #undef st_atime_nsec 270 #undef st_mtime_nsec 271 #undef st_ctime_nsec 272 #endif 273 static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) { 274 internal_memset(out, 0, sizeof(*out)); 275 out->st_dev = in->st_dev; 276 out->st_ino = in->st_ino; 277 out->st_mode = in->st_mode; 278 out->st_nlink = in->st_nlink; 279 out->st_uid = in->st_uid; 280 out->st_gid = in->st_gid; 281 out->st_rdev = in->st_rdev; 282 out->st_size = in->st_size; 283 out->st_blksize = in->st_blksize; 284 out->st_blocks = in->st_blocks; 285 #if defined(__USE_MISC) || \ 286 defined(__USE_XOPEN2K8) || \ 287 defined(SANITIZER_ANDROID) 288 out->st_atim.tv_sec = in->st_atime; 289 out->st_atim.tv_nsec = in->st_atime_nsec; 290 out->st_mtim.tv_sec = in->st_mtime; 291 out->st_mtim.tv_nsec = in->st_mtime_nsec; 292 out->st_ctim.tv_sec = in->st_ctime; 293 out->st_ctim.tv_nsec = in->st_ctime_nsec; 294 #else 295 out->st_atime = in->st_atime; 296 out->st_atimensec = in->st_atime_nsec; 297 out->st_mtime = in->st_mtime; 298 out->st_mtimensec = in->st_mtime_nsec; 299 out->st_ctime = in->st_ctime; 300 out->st_atimensec = in->st_ctime_nsec; 301 #endif 302 } 303 #endif 304 305 uptr internal_stat(const char *path, void *buf) { 306 #if SANITIZER_FREEBSD 307 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 0); 308 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 309 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 310 0); 311 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 312 # if defined(__mips64) 313 // For mips64, stat syscall fills buffer in the format of kernel_stat 314 struct kernel_stat kbuf; 315 int res = internal_syscall(SYSCALL(stat), path, &kbuf); 316 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 317 return res; 318 # else 319 return internal_syscall(SYSCALL(stat), (uptr)path, (uptr)buf); 320 # endif 321 #else 322 struct stat64 buf64; 323 int res = internal_syscall(SYSCALL(stat64), path, &buf64); 324 stat64_to_stat(&buf64, (struct stat *)buf); 325 return res; 326 #endif 327 } 328 329 uptr internal_lstat(const char *path, void *buf) { 330 #if SANITIZER_FREEBSD 331 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 332 AT_SYMLINK_NOFOLLOW); 333 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 334 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 335 AT_SYMLINK_NOFOLLOW); 336 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 337 # if SANITIZER_MIPS64 338 // For mips64, lstat syscall fills buffer in the format of kernel_stat 339 struct kernel_stat kbuf; 340 int res = internal_syscall(SYSCALL(lstat), path, &kbuf); 341 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 342 return res; 343 # else 344 return internal_syscall(SYSCALL(lstat), (uptr)path, (uptr)buf); 345 # endif 346 #else 347 struct stat64 buf64; 348 int res = internal_syscall(SYSCALL(lstat64), path, &buf64); 349 stat64_to_stat(&buf64, (struct stat *)buf); 350 return res; 351 #endif 352 } 353 354 uptr internal_fstat(fd_t fd, void *buf) { 355 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 356 #if SANITIZER_MIPS64 357 // For mips64, fstat syscall fills buffer in the format of kernel_stat 358 struct kernel_stat kbuf; 359 int res = internal_syscall(SYSCALL(fstat), fd, &kbuf); 360 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 361 return res; 362 # else 363 return internal_syscall(SYSCALL(fstat), fd, (uptr)buf); 364 # endif 365 #else 366 struct stat64 buf64; 367 int res = internal_syscall(SYSCALL(fstat64), fd, &buf64); 368 stat64_to_stat(&buf64, (struct stat *)buf); 369 return res; 370 #endif 371 } 372 373 uptr internal_filesize(fd_t fd) { 374 struct stat st; 375 if (internal_fstat(fd, &st)) 376 return -1; 377 return (uptr)st.st_size; 378 } 379 380 uptr internal_dup(int oldfd) { 381 return internal_syscall(SYSCALL(dup), oldfd); 382 } 383 384 uptr internal_dup2(int oldfd, int newfd) { 385 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 386 return internal_syscall(SYSCALL(dup3), oldfd, newfd, 0); 387 #else 388 return internal_syscall(SYSCALL(dup2), oldfd, newfd); 389 #endif 390 } 391 392 uptr internal_readlink(const char *path, char *buf, uptr bufsize) { 393 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 394 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD, (uptr)path, (uptr)buf, 395 bufsize); 396 #else 397 return internal_syscall(SYSCALL(readlink), (uptr)path, (uptr)buf, bufsize); 398 #endif 399 } 400 401 uptr internal_unlink(const char *path) { 402 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 403 return internal_syscall(SYSCALL(unlinkat), AT_FDCWD, (uptr)path, 0); 404 #else 405 return internal_syscall(SYSCALL(unlink), (uptr)path); 406 #endif 407 } 408 409 uptr internal_rename(const char *oldpath, const char *newpath) { 410 #if defined(__riscv) 411 return internal_syscall(SYSCALL(renameat2), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 412 (uptr)newpath, 0); 413 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 414 return internal_syscall(SYSCALL(renameat), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 415 (uptr)newpath); 416 #else 417 return internal_syscall(SYSCALL(rename), (uptr)oldpath, (uptr)newpath); 418 #endif 419 } 420 421 uptr internal_sched_yield() { 422 return internal_syscall(SYSCALL(sched_yield)); 423 } 424 425 unsigned int internal_sleep(unsigned int seconds) { 426 struct timespec ts; 427 ts.tv_sec = seconds; 428 ts.tv_nsec = 0; 429 int res = internal_syscall(SYSCALL(nanosleep), &ts, &ts); 430 if (res) return ts.tv_sec; 431 return 0; 432 } 433 434 uptr internal_execve(const char *filename, char *const argv[], 435 char *const envp[]) { 436 return internal_syscall(SYSCALL(execve), (uptr)filename, (uptr)argv, 437 (uptr)envp); 438 } 439 #endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD 440 441 #if !SANITIZER_NETBSD 442 void internal__exit(int exitcode) { 443 #if SANITIZER_FREEBSD || SANITIZER_SOLARIS 444 internal_syscall(SYSCALL(exit), exitcode); 445 #else 446 internal_syscall(SYSCALL(exit_group), exitcode); 447 #endif 448 Die(); // Unreachable. 449 } 450 #endif // !SANITIZER_NETBSD 451 452 // ----------------- sanitizer_common.h 453 bool FileExists(const char *filename) { 454 if (ShouldMockFailureToOpen(filename)) 455 return false; 456 struct stat st; 457 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 458 if (internal_syscall(SYSCALL(newfstatat), AT_FDCWD, filename, &st, 0)) 459 #else 460 if (internal_stat(filename, &st)) 461 #endif 462 return false; 463 // Sanity check: filename is a regular file. 464 return S_ISREG(st.st_mode); 465 } 466 467 #if !SANITIZER_NETBSD 468 tid_t GetTid() { 469 #if SANITIZER_FREEBSD 470 long Tid; 471 thr_self(&Tid); 472 return Tid; 473 #elif SANITIZER_SOLARIS 474 return thr_self(); 475 #else 476 return internal_syscall(SYSCALL(gettid)); 477 #endif 478 } 479 480 int TgKill(pid_t pid, tid_t tid, int sig) { 481 #if SANITIZER_LINUX 482 return internal_syscall(SYSCALL(tgkill), pid, tid, sig); 483 #elif SANITIZER_FREEBSD 484 return internal_syscall(SYSCALL(thr_kill2), pid, tid, sig); 485 #elif SANITIZER_SOLARIS 486 (void)pid; 487 return thr_kill(tid, sig); 488 #endif 489 } 490 #endif 491 492 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 493 u64 NanoTime() { 494 #if SANITIZER_FREEBSD 495 timeval tv; 496 #else 497 kernel_timeval tv; 498 #endif 499 internal_memset(&tv, 0, sizeof(tv)); 500 internal_syscall(SYSCALL(gettimeofday), &tv, 0); 501 return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000; 502 } 503 #endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD 504 505 #if SANITIZER_GLIBC 506 uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) { 507 return internal_syscall(SYSCALL(clock_gettime), clk_id, tp); 508 } 509 #endif // SANITIZER_GLIBC 510 511 // Like getenv, but reads env directly from /proc (on Linux) or parses the 512 // 'environ' array (on some others) and does not use libc. This function 513 // should be called first inside __asan_init. 514 const char *GetEnv(const char *name) { 515 #if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_SOLARIS 516 if (::environ != 0) { 517 uptr NameLen = internal_strlen(name); 518 for (char **Env = ::environ; *Env != 0; Env++) { 519 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=') 520 return (*Env) + NameLen + 1; 521 } 522 } 523 return 0; // Not found. 524 #elif SANITIZER_LINUX 525 static char *environ; 526 static uptr len; 527 static bool inited; 528 if (!inited) { 529 inited = true; 530 uptr environ_size; 531 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len)) 532 environ = nullptr; 533 } 534 if (!environ || len == 0) return nullptr; 535 uptr namelen = internal_strlen(name); 536 const char *p = environ; 537 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer 538 // proc file has the format NAME=value\0NAME=value\0NAME=value\0... 539 const char* endp = 540 (char*)internal_memchr(p, '\0', len - (p - environ)); 541 if (!endp) // this entry isn't NUL terminated 542 return nullptr; 543 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match. 544 return p + namelen + 1; // point after = 545 p = endp + 1; 546 } 547 return nullptr; // Not found. 548 #else 549 #error "Unsupported platform" 550 #endif 551 } 552 553 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD && !SANITIZER_GO 554 extern "C" { 555 SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end; 556 } 557 #endif 558 559 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD 560 static void ReadNullSepFileToArray(const char *path, char ***arr, 561 int arr_size) { 562 char *buff; 563 uptr buff_size; 564 uptr buff_len; 565 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray"); 566 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) { 567 (*arr)[0] = nullptr; 568 return; 569 } 570 (*arr)[0] = buff; 571 int count, i; 572 for (count = 1, i = 1; ; i++) { 573 if (buff[i] == 0) { 574 if (buff[i+1] == 0) break; 575 (*arr)[count] = &buff[i+1]; 576 CHECK_LE(count, arr_size - 1); // FIXME: make this more flexible. 577 count++; 578 } 579 } 580 (*arr)[count] = nullptr; 581 } 582 #endif 583 584 static void GetArgsAndEnv(char ***argv, char ***envp) { 585 #if SANITIZER_FREEBSD 586 // On FreeBSD, retrieving the argument and environment arrays is done via the 587 // kern.ps_strings sysctl, which returns a pointer to a structure containing 588 // this information. See also <sys/exec.h>. 589 ps_strings *pss; 590 uptr sz = sizeof(pss); 591 if (internal_sysctlbyname("kern.ps_strings", &pss, &sz, NULL, 0) == -1) { 592 Printf("sysctl kern.ps_strings failed\n"); 593 Die(); 594 } 595 *argv = pss->ps_argvstr; 596 *envp = pss->ps_envstr; 597 #elif SANITIZER_NETBSD 598 *argv = __ps_strings->ps_argvstr; 599 *envp = __ps_strings->ps_envstr; 600 #else // SANITIZER_FREEBSD 601 #if !SANITIZER_GO 602 if (&__libc_stack_end) { 603 uptr* stack_end = (uptr*)__libc_stack_end; 604 // Normally argc can be obtained from *stack_end, however, on ARM glibc's 605 // _start clobbers it: 606 // https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/arm/start.S;hb=refs/heads/release/2.31/master#l75 607 // Do not special-case ARM and infer argc from argv everywhere. 608 int argc = 0; 609 while (stack_end[argc + 1]) argc++; 610 *argv = (char**)(stack_end + 1); 611 *envp = (char**)(stack_end + argc + 2); 612 } else { 613 #endif // !SANITIZER_GO 614 static const int kMaxArgv = 2000, kMaxEnvp = 2000; 615 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv); 616 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp); 617 #if !SANITIZER_GO 618 } 619 #endif // !SANITIZER_GO 620 #endif // SANITIZER_FREEBSD 621 } 622 623 char **GetArgv() { 624 char **argv, **envp; 625 GetArgsAndEnv(&argv, &envp); 626 return argv; 627 } 628 629 char **GetEnviron() { 630 char **argv, **envp; 631 GetArgsAndEnv(&argv, &envp); 632 return envp; 633 } 634 635 #if !SANITIZER_SOLARIS 636 enum MutexState { 637 MtxUnlocked = 0, 638 MtxLocked = 1, 639 MtxSleeping = 2 640 }; 641 642 BlockingMutex::BlockingMutex() { 643 internal_memset(this, 0, sizeof(*this)); 644 } 645 646 void BlockingMutex::Lock() { 647 CHECK_EQ(owner_, 0); 648 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 649 if (atomic_exchange(m, MtxLocked, memory_order_acquire) == MtxUnlocked) 650 return; 651 while (atomic_exchange(m, MtxSleeping, memory_order_acquire) != MtxUnlocked) { 652 #if SANITIZER_FREEBSD 653 _umtx_op(m, UMTX_OP_WAIT_UINT, MtxSleeping, 0, 0); 654 #elif SANITIZER_NETBSD 655 sched_yield(); /* No userspace futex-like synchronization */ 656 #else 657 internal_syscall(SYSCALL(futex), (uptr)m, FUTEX_WAIT_PRIVATE, MtxSleeping, 658 0, 0, 0); 659 #endif 660 } 661 } 662 663 void BlockingMutex::Unlock() { 664 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 665 u32 v = atomic_exchange(m, MtxUnlocked, memory_order_release); 666 CHECK_NE(v, MtxUnlocked); 667 if (v == MtxSleeping) { 668 #if SANITIZER_FREEBSD 669 _umtx_op(m, UMTX_OP_WAKE, 1, 0, 0); 670 #elif SANITIZER_NETBSD 671 /* No userspace futex-like synchronization */ 672 #else 673 internal_syscall(SYSCALL(futex), (uptr)m, FUTEX_WAKE_PRIVATE, 1, 0, 0, 0); 674 #endif 675 } 676 } 677 678 void BlockingMutex::CheckLocked() { 679 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 680 CHECK_NE(MtxUnlocked, atomic_load(m, memory_order_relaxed)); 681 } 682 #endif // !SANITIZER_SOLARIS 683 684 // ----------------- sanitizer_linux.h 685 // The actual size of this structure is specified by d_reclen. 686 // Note that getdents64 uses a different structure format. We only provide the 687 // 32-bit syscall here. 688 #if SANITIZER_NETBSD 689 // Not used 690 #else 691 struct linux_dirent { 692 #if SANITIZER_X32 || defined(__aarch64__) || SANITIZER_RISCV64 693 u64 d_ino; 694 u64 d_off; 695 #else 696 unsigned long d_ino; 697 unsigned long d_off; 698 #endif 699 unsigned short d_reclen; 700 #if defined(__aarch64__) || SANITIZER_RISCV64 701 unsigned char d_type; 702 #endif 703 char d_name[256]; 704 }; 705 #endif 706 707 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 708 // Syscall wrappers. 709 uptr internal_ptrace(int request, int pid, void *addr, void *data) { 710 return internal_syscall(SYSCALL(ptrace), request, pid, (uptr)addr, 711 (uptr)data); 712 } 713 714 uptr internal_waitpid(int pid, int *status, int options) { 715 return internal_syscall(SYSCALL(wait4), pid, (uptr)status, options, 716 0 /* rusage */); 717 } 718 719 uptr internal_getpid() { 720 return internal_syscall(SYSCALL(getpid)); 721 } 722 723 uptr internal_getppid() { 724 return internal_syscall(SYSCALL(getppid)); 725 } 726 727 int internal_dlinfo(void *handle, int request, void *p) { 728 #if SANITIZER_FREEBSD 729 return dlinfo(handle, request, p); 730 #else 731 UNIMPLEMENTED(); 732 #endif 733 } 734 735 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) { 736 #if SANITIZER_FREEBSD 737 return internal_syscall(SYSCALL(getdirentries), fd, (uptr)dirp, count, NULL); 738 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 739 return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count); 740 #else 741 return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count); 742 #endif 743 } 744 745 uptr internal_lseek(fd_t fd, OFF_T offset, int whence) { 746 return internal_syscall(SYSCALL(lseek), fd, offset, whence); 747 } 748 749 #if SANITIZER_LINUX 750 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) { 751 return internal_syscall(SYSCALL(prctl), option, arg2, arg3, arg4, arg5); 752 } 753 #endif 754 755 uptr internal_sigaltstack(const void *ss, void *oss) { 756 return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss); 757 } 758 759 int internal_fork() { 760 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 761 return internal_syscall(SYSCALL(clone), SIGCHLD, 0); 762 #else 763 return internal_syscall(SYSCALL(fork)); 764 #endif 765 } 766 767 #if SANITIZER_FREEBSD 768 int internal_sysctl(const int *name, unsigned int namelen, void *oldp, 769 uptr *oldlenp, const void *newp, uptr newlen) { 770 return internal_syscall(SYSCALL(__sysctl), name, namelen, oldp, 771 (size_t *)oldlenp, newp, (size_t)newlen); 772 } 773 774 int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp, 775 const void *newp, uptr newlen) { 776 // Note: this function can be called during startup, so we need to avoid 777 // calling any interceptable functions. On FreeBSD >= 1300045 sysctlbyname() 778 // is a real syscall, but for older versions it calls sysctlnametomib() 779 // followed by sysctl(). To avoid calling the intercepted version and 780 // asserting if this happens during startup, call the real sysctlnametomib() 781 // followed by internal_sysctl() if the syscall is not available. 782 #ifdef SYS___sysctlbyname 783 return internal_syscall(SYSCALL(__sysctlbyname), sname, 784 internal_strlen(sname), oldp, (size_t *)oldlenp, newp, 785 (size_t)newlen); 786 #else 787 static decltype(sysctlnametomib) *real_sysctlnametomib = nullptr; 788 if (!real_sysctlnametomib) 789 real_sysctlnametomib = 790 (decltype(sysctlnametomib) *)dlsym(RTLD_NEXT, "sysctlnametomib"); 791 CHECK(real_sysctlnametomib); 792 793 int oid[CTL_MAXNAME]; 794 size_t len = CTL_MAXNAME; 795 if (real_sysctlnametomib(sname, oid, &len) == -1) 796 return (-1); 797 return internal_sysctl(oid, len, oldp, oldlenp, newp, newlen); 798 #endif 799 } 800 #endif 801 802 #if SANITIZER_LINUX 803 #define SA_RESTORER 0x04000000 804 // Doesn't set sa_restorer if the caller did not set it, so use with caution 805 //(see below). 806 int internal_sigaction_norestorer(int signum, const void *act, void *oldact) { 807 __sanitizer_kernel_sigaction_t k_act, k_oldact; 808 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t)); 809 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t)); 810 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act; 811 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact; 812 if (u_act) { 813 k_act.handler = u_act->handler; 814 k_act.sigaction = u_act->sigaction; 815 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask, 816 sizeof(__sanitizer_kernel_sigset_t)); 817 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL). 818 k_act.sa_flags = u_act->sa_flags | SA_RESTORER; 819 // FIXME: most often sa_restorer is unset, however the kernel requires it 820 // to point to a valid signal restorer that calls the rt_sigreturn syscall. 821 // If sa_restorer passed to the kernel is NULL, the program may crash upon 822 // signal delivery or fail to unwind the stack in the signal handler. 823 // libc implementation of sigaction() passes its own restorer to 824 // rt_sigaction, so we need to do the same (we'll need to reimplement the 825 // restorers; for x86_64 the restorer address can be obtained from 826 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact). 827 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 828 k_act.sa_restorer = u_act->sa_restorer; 829 #endif 830 } 831 832 uptr result = internal_syscall(SYSCALL(rt_sigaction), (uptr)signum, 833 (uptr)(u_act ? &k_act : nullptr), 834 (uptr)(u_oldact ? &k_oldact : nullptr), 835 (uptr)sizeof(__sanitizer_kernel_sigset_t)); 836 837 if ((result == 0) && u_oldact) { 838 u_oldact->handler = k_oldact.handler; 839 u_oldact->sigaction = k_oldact.sigaction; 840 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask, 841 sizeof(__sanitizer_kernel_sigset_t)); 842 u_oldact->sa_flags = k_oldact.sa_flags; 843 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 844 u_oldact->sa_restorer = k_oldact.sa_restorer; 845 #endif 846 } 847 return result; 848 } 849 #endif // SANITIZER_LINUX 850 851 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set, 852 __sanitizer_sigset_t *oldset) { 853 #if SANITIZER_FREEBSD 854 return internal_syscall(SYSCALL(sigprocmask), how, set, oldset); 855 #else 856 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 857 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset; 858 return internal_syscall(SYSCALL(rt_sigprocmask), (uptr)how, (uptr)k_set, 859 (uptr)k_oldset, sizeof(__sanitizer_kernel_sigset_t)); 860 #endif 861 } 862 863 void internal_sigfillset(__sanitizer_sigset_t *set) { 864 internal_memset(set, 0xff, sizeof(*set)); 865 } 866 867 void internal_sigemptyset(__sanitizer_sigset_t *set) { 868 internal_memset(set, 0, sizeof(*set)); 869 } 870 871 #if SANITIZER_LINUX 872 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 873 signum -= 1; 874 CHECK_GE(signum, 0); 875 CHECK_LT(signum, sizeof(*set) * 8); 876 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 877 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 878 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 879 k_set->sig[idx] &= ~(1 << bit); 880 } 881 882 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 883 signum -= 1; 884 CHECK_GE(signum, 0); 885 CHECK_LT(signum, sizeof(*set) * 8); 886 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 887 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 888 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 889 return k_set->sig[idx] & (1 << bit); 890 } 891 #elif SANITIZER_FREEBSD 892 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 893 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 894 sigdelset(rset, signum); 895 } 896 897 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 898 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 899 return sigismember(rset, signum); 900 } 901 #endif 902 #endif // !SANITIZER_SOLARIS 903 904 #if !SANITIZER_NETBSD 905 // ThreadLister implementation. 906 ThreadLister::ThreadLister(pid_t pid) : pid_(pid), buffer_(4096) { 907 char task_directory_path[80]; 908 internal_snprintf(task_directory_path, sizeof(task_directory_path), 909 "/proc/%d/task/", pid); 910 descriptor_ = internal_open(task_directory_path, O_RDONLY | O_DIRECTORY); 911 if (internal_iserror(descriptor_)) { 912 Report("Can't open /proc/%d/task for reading.\n", pid); 913 } 914 } 915 916 ThreadLister::Result ThreadLister::ListThreads( 917 InternalMmapVector<tid_t> *threads) { 918 if (internal_iserror(descriptor_)) 919 return Error; 920 internal_lseek(descriptor_, 0, SEEK_SET); 921 threads->clear(); 922 923 Result result = Ok; 924 for (bool first_read = true;; first_read = false) { 925 // Resize to max capacity if it was downsized by IsAlive. 926 buffer_.resize(buffer_.capacity()); 927 CHECK_GE(buffer_.size(), 4096); 928 uptr read = internal_getdents( 929 descriptor_, (struct linux_dirent *)buffer_.data(), buffer_.size()); 930 if (!read) 931 return result; 932 if (internal_iserror(read)) { 933 Report("Can't read directory entries from /proc/%d/task.\n", pid_); 934 return Error; 935 } 936 937 for (uptr begin = (uptr)buffer_.data(), end = begin + read; begin < end;) { 938 struct linux_dirent *entry = (struct linux_dirent *)begin; 939 begin += entry->d_reclen; 940 if (entry->d_ino == 1) { 941 // Inode 1 is for bad blocks and also can be a reason for early return. 942 // Should be emitted if kernel tried to output terminating thread. 943 // See proc_task_readdir implementation in Linux. 944 result = Incomplete; 945 } 946 if (entry->d_ino && *entry->d_name >= '0' && *entry->d_name <= '9') 947 threads->push_back(internal_atoll(entry->d_name)); 948 } 949 950 // Now we are going to detect short-read or early EOF. In such cases Linux 951 // can return inconsistent list with missing alive threads. 952 // Code will just remember that the list can be incomplete but it will 953 // continue reads to return as much as possible. 954 if (!first_read) { 955 // The first one was a short-read by definition. 956 result = Incomplete; 957 } else if (read > buffer_.size() - 1024) { 958 // Read was close to the buffer size. So double the size and assume the 959 // worst. 960 buffer_.resize(buffer_.size() * 2); 961 result = Incomplete; 962 } else if (!threads->empty() && !IsAlive(threads->back())) { 963 // Maybe Linux early returned from read on terminated thread (!pid_alive) 964 // and failed to restore read position. 965 // See next_tid and proc_task_instantiate in Linux. 966 result = Incomplete; 967 } 968 } 969 } 970 971 bool ThreadLister::IsAlive(int tid) { 972 // /proc/%d/task/%d/status uses same call to detect alive threads as 973 // proc_task_readdir. See task_state implementation in Linux. 974 char path[80]; 975 internal_snprintf(path, sizeof(path), "/proc/%d/task/%d/status", pid_, tid); 976 if (!ReadFileToVector(path, &buffer_) || buffer_.empty()) 977 return false; 978 buffer_.push_back(0); 979 static const char kPrefix[] = "\nPPid:"; 980 const char *field = internal_strstr(buffer_.data(), kPrefix); 981 if (!field) 982 return false; 983 field += internal_strlen(kPrefix); 984 return (int)internal_atoll(field) != 0; 985 } 986 987 ThreadLister::~ThreadLister() { 988 if (!internal_iserror(descriptor_)) 989 internal_close(descriptor_); 990 } 991 #endif 992 993 #if SANITIZER_WORDSIZE == 32 994 // Take care of unusable kernel area in top gigabyte. 995 static uptr GetKernelAreaSize() { 996 #if SANITIZER_LINUX && !SANITIZER_X32 997 const uptr gbyte = 1UL << 30; 998 999 // Firstly check if there are writable segments 1000 // mapped to top gigabyte (e.g. stack). 1001 MemoryMappingLayout proc_maps(/*cache_enabled*/true); 1002 if (proc_maps.Error()) 1003 return 0; 1004 MemoryMappedSegment segment; 1005 while (proc_maps.Next(&segment)) { 1006 if ((segment.end >= 3 * gbyte) && segment.IsWritable()) return 0; 1007 } 1008 1009 #if !SANITIZER_ANDROID 1010 // Even if nothing is mapped, top Gb may still be accessible 1011 // if we are running on 64-bit kernel. 1012 // Uname may report misleading results if personality type 1013 // is modified (e.g. under schroot) so check this as well. 1014 struct utsname uname_info; 1015 int pers = personality(0xffffffffUL); 1016 if (!(pers & PER_MASK) && internal_uname(&uname_info) == 0 && 1017 internal_strstr(uname_info.machine, "64")) 1018 return 0; 1019 #endif // SANITIZER_ANDROID 1020 1021 // Top gigabyte is reserved for kernel. 1022 return gbyte; 1023 #else 1024 return 0; 1025 #endif // SANITIZER_LINUX && !SANITIZER_X32 1026 } 1027 #endif // SANITIZER_WORDSIZE == 32 1028 1029 uptr GetMaxVirtualAddress() { 1030 #if SANITIZER_NETBSD && defined(__x86_64__) 1031 return 0x7f7ffffff000ULL; // (0x00007f8000000000 - PAGE_SIZE) 1032 #elif SANITIZER_WORDSIZE == 64 1033 # if defined(__powerpc64__) || defined(__aarch64__) 1034 // On PowerPC64 we have two different address space layouts: 44- and 46-bit. 1035 // We somehow need to figure out which one we are using now and choose 1036 // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL. 1037 // Note that with 'ulimit -s unlimited' the stack is moved away from the top 1038 // of the address space, so simply checking the stack address is not enough. 1039 // This should (does) work for both PowerPC64 Endian modes. 1040 // Similarly, aarch64 has multiple address space layouts: 39, 42 and 47-bit. 1041 return (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1)) - 1; 1042 #elif SANITIZER_RISCV64 1043 return (1ULL << 38) - 1; 1044 # elif defined(__mips64) 1045 return (1ULL << 40) - 1; // 0x000000ffffffffffUL; 1046 # elif defined(__s390x__) 1047 return (1ULL << 53) - 1; // 0x001fffffffffffffUL; 1048 #elif defined(__sparc__) 1049 return ~(uptr)0; 1050 # else 1051 return (1ULL << 47) - 1; // 0x00007fffffffffffUL; 1052 # endif 1053 #else // SANITIZER_WORDSIZE == 32 1054 # if defined(__s390__) 1055 return (1ULL << 31) - 1; // 0x7fffffff; 1056 # else 1057 return (1ULL << 32) - 1; // 0xffffffff; 1058 # endif 1059 #endif // SANITIZER_WORDSIZE 1060 } 1061 1062 uptr GetMaxUserVirtualAddress() { 1063 uptr addr = GetMaxVirtualAddress(); 1064 #if SANITIZER_WORDSIZE == 32 && !defined(__s390__) 1065 if (!common_flags()->full_address_space) 1066 addr -= GetKernelAreaSize(); 1067 CHECK_LT(reinterpret_cast<uptr>(&addr), addr); 1068 #endif 1069 return addr; 1070 } 1071 1072 #if !SANITIZER_ANDROID 1073 uptr GetPageSize() { 1074 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__i386__)) && \ 1075 defined(EXEC_PAGESIZE) 1076 return EXEC_PAGESIZE; 1077 #elif SANITIZER_FREEBSD || SANITIZER_NETBSD 1078 // Use sysctl as sysconf can trigger interceptors internally. 1079 int pz = 0; 1080 uptr pzl = sizeof(pz); 1081 int mib[2] = {CTL_HW, HW_PAGESIZE}; 1082 int rv = internal_sysctl(mib, 2, &pz, &pzl, nullptr, 0); 1083 CHECK_EQ(rv, 0); 1084 return (uptr)pz; 1085 #elif SANITIZER_USE_GETAUXVAL 1086 return getauxval(AT_PAGESZ); 1087 #else 1088 return sysconf(_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy. 1089 #endif 1090 } 1091 #endif // !SANITIZER_ANDROID 1092 1093 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) { 1094 #if SANITIZER_SOLARIS 1095 const char *default_module_name = getexecname(); 1096 CHECK_NE(default_module_name, NULL); 1097 return internal_snprintf(buf, buf_len, "%s", default_module_name); 1098 #else 1099 #if SANITIZER_FREEBSD || SANITIZER_NETBSD 1100 #if SANITIZER_FREEBSD 1101 const int Mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1}; 1102 #else 1103 const int Mib[4] = {CTL_KERN, KERN_PROC_ARGS, -1, KERN_PROC_PATHNAME}; 1104 #endif 1105 const char *default_module_name = "kern.proc.pathname"; 1106 uptr Size = buf_len; 1107 bool IsErr = 1108 (internal_sysctl(Mib, ARRAY_SIZE(Mib), buf, &Size, NULL, 0) != 0); 1109 int readlink_error = IsErr ? errno : 0; 1110 uptr module_name_len = Size; 1111 #else 1112 const char *default_module_name = "/proc/self/exe"; 1113 uptr module_name_len = internal_readlink( 1114 default_module_name, buf, buf_len); 1115 int readlink_error; 1116 bool IsErr = internal_iserror(module_name_len, &readlink_error); 1117 #endif // SANITIZER_SOLARIS 1118 if (IsErr) { 1119 // We can't read binary name for some reason, assume it's unknown. 1120 Report("WARNING: reading executable name failed with errno %d, " 1121 "some stack frames may not be symbolized\n", readlink_error); 1122 module_name_len = internal_snprintf(buf, buf_len, "%s", 1123 default_module_name); 1124 CHECK_LT(module_name_len, buf_len); 1125 } 1126 return module_name_len; 1127 #endif 1128 } 1129 1130 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) { 1131 #if SANITIZER_LINUX 1132 char *tmpbuf; 1133 uptr tmpsize; 1134 uptr tmplen; 1135 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen, 1136 1024 * 1024)) { 1137 internal_strncpy(buf, tmpbuf, buf_len); 1138 UnmapOrDie(tmpbuf, tmpsize); 1139 return internal_strlen(buf); 1140 } 1141 #endif 1142 return ReadBinaryName(buf, buf_len); 1143 } 1144 1145 // Match full names of the form /path/to/base_name{-,.}* 1146 bool LibraryNameIs(const char *full_name, const char *base_name) { 1147 const char *name = full_name; 1148 // Strip path. 1149 while (*name != '\0') name++; 1150 while (name > full_name && *name != '/') name--; 1151 if (*name == '/') name++; 1152 uptr base_name_length = internal_strlen(base_name); 1153 if (internal_strncmp(name, base_name, base_name_length)) return false; 1154 return (name[base_name_length] == '-' || name[base_name_length] == '.'); 1155 } 1156 1157 #if !SANITIZER_ANDROID 1158 // Call cb for each region mapped by map. 1159 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) { 1160 CHECK_NE(map, nullptr); 1161 #if !SANITIZER_FREEBSD 1162 typedef ElfW(Phdr) Elf_Phdr; 1163 typedef ElfW(Ehdr) Elf_Ehdr; 1164 #endif // !SANITIZER_FREEBSD 1165 char *base = (char *)map->l_addr; 1166 Elf_Ehdr *ehdr = (Elf_Ehdr *)base; 1167 char *phdrs = base + ehdr->e_phoff; 1168 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize; 1169 1170 // Find the segment with the minimum base so we can "relocate" the p_vaddr 1171 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC 1172 // objects have a non-zero base. 1173 uptr preferred_base = (uptr)-1; 1174 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1175 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1176 if (phdr->p_type == PT_LOAD && preferred_base > (uptr)phdr->p_vaddr) 1177 preferred_base = (uptr)phdr->p_vaddr; 1178 } 1179 1180 // Compute the delta from the real base to get a relocation delta. 1181 sptr delta = (uptr)base - preferred_base; 1182 // Now we can figure out what the loader really mapped. 1183 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1184 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1185 if (phdr->p_type == PT_LOAD) { 1186 uptr seg_start = phdr->p_vaddr + delta; 1187 uptr seg_end = seg_start + phdr->p_memsz; 1188 // None of these values are aligned. We consider the ragged edges of the 1189 // load command as defined, since they are mapped from the file. 1190 seg_start = RoundDownTo(seg_start, GetPageSizeCached()); 1191 seg_end = RoundUpTo(seg_end, GetPageSizeCached()); 1192 cb((void *)seg_start, seg_end - seg_start); 1193 } 1194 } 1195 } 1196 #endif 1197 1198 #if defined(__x86_64__) && SANITIZER_LINUX 1199 // We cannot use glibc's clone wrapper, because it messes with the child 1200 // task's TLS. It writes the PID and TID of the child task to its thread 1201 // descriptor, but in our case the child task shares the thread descriptor with 1202 // the parent (because we don't know how to allocate a new thread 1203 // descriptor to keep glibc happy). So the stock version of clone(), when 1204 // used with CLONE_VM, would end up corrupting the parent's thread descriptor. 1205 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1206 int *parent_tidptr, void *newtls, int *child_tidptr) { 1207 long long res; 1208 if (!fn || !child_stack) 1209 return -EINVAL; 1210 CHECK_EQ(0, (uptr)child_stack % 16); 1211 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1212 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1213 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1214 register void *r8 __asm__("r8") = newtls; 1215 register int *r10 __asm__("r10") = child_tidptr; 1216 __asm__ __volatile__( 1217 /* %rax = syscall(%rax = SYSCALL(clone), 1218 * %rdi = flags, 1219 * %rsi = child_stack, 1220 * %rdx = parent_tidptr, 1221 * %r8 = new_tls, 1222 * %r10 = child_tidptr) 1223 */ 1224 "syscall\n" 1225 1226 /* if (%rax != 0) 1227 * return; 1228 */ 1229 "testq %%rax,%%rax\n" 1230 "jnz 1f\n" 1231 1232 /* In the child. Terminate unwind chain. */ 1233 // XXX: We should also terminate the CFI unwind chain 1234 // here. Unfortunately clang 3.2 doesn't support the 1235 // necessary CFI directives, so we skip that part. 1236 "xorq %%rbp,%%rbp\n" 1237 1238 /* Call "fn(arg)". */ 1239 "popq %%rax\n" 1240 "popq %%rdi\n" 1241 "call *%%rax\n" 1242 1243 /* Call _exit(%rax). */ 1244 "movq %%rax,%%rdi\n" 1245 "movq %2,%%rax\n" 1246 "syscall\n" 1247 1248 /* Return to parent. */ 1249 "1:\n" 1250 : "=a" (res) 1251 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1252 "S"(child_stack), 1253 "D"(flags), 1254 "d"(parent_tidptr), 1255 "r"(r8), 1256 "r"(r10) 1257 : "memory", "r11", "rcx"); 1258 return res; 1259 } 1260 #elif defined(__mips__) 1261 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1262 int *parent_tidptr, void *newtls, int *child_tidptr) { 1263 long long res; 1264 if (!fn || !child_stack) 1265 return -EINVAL; 1266 CHECK_EQ(0, (uptr)child_stack % 16); 1267 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1268 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1269 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1270 register void *a3 __asm__("$7") = newtls; 1271 register int *a4 __asm__("$8") = child_tidptr; 1272 // We don't have proper CFI directives here because it requires alot of code 1273 // for very marginal benefits. 1274 __asm__ __volatile__( 1275 /* $v0 = syscall($v0 = __NR_clone, 1276 * $a0 = flags, 1277 * $a1 = child_stack, 1278 * $a2 = parent_tidptr, 1279 * $a3 = new_tls, 1280 * $a4 = child_tidptr) 1281 */ 1282 ".cprestore 16;\n" 1283 "move $4,%1;\n" 1284 "move $5,%2;\n" 1285 "move $6,%3;\n" 1286 "move $7,%4;\n" 1287 /* Store the fifth argument on stack 1288 * if we are using 32-bit abi. 1289 */ 1290 #if SANITIZER_WORDSIZE == 32 1291 "lw %5,16($29);\n" 1292 #else 1293 "move $8,%5;\n" 1294 #endif 1295 "li $2,%6;\n" 1296 "syscall;\n" 1297 1298 /* if ($v0 != 0) 1299 * return; 1300 */ 1301 "bnez $2,1f;\n" 1302 1303 /* Call "fn(arg)". */ 1304 #if SANITIZER_WORDSIZE == 32 1305 #ifdef __BIG_ENDIAN__ 1306 "lw $25,4($29);\n" 1307 "lw $4,12($29);\n" 1308 #else 1309 "lw $25,0($29);\n" 1310 "lw $4,8($29);\n" 1311 #endif 1312 #else 1313 "ld $25,0($29);\n" 1314 "ld $4,8($29);\n" 1315 #endif 1316 "jal $25;\n" 1317 1318 /* Call _exit($v0). */ 1319 "move $4,$2;\n" 1320 "li $2,%7;\n" 1321 "syscall;\n" 1322 1323 /* Return to parent. */ 1324 "1:\n" 1325 : "=r" (res) 1326 : "r"(flags), 1327 "r"(child_stack), 1328 "r"(parent_tidptr), 1329 "r"(a3), 1330 "r"(a4), 1331 "i"(__NR_clone), 1332 "i"(__NR_exit) 1333 : "memory", "$29" ); 1334 return res; 1335 } 1336 #elif SANITIZER_RISCV64 1337 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1338 int *parent_tidptr, void *newtls, int *child_tidptr) { 1339 if (!fn || !child_stack) 1340 return -EINVAL; 1341 CHECK_EQ(0, (uptr)child_stack % 16); 1342 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1343 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1344 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1345 1346 int tid = internal_syscall(SYSCALL(clone), (unsigned long)flags, child_stack, 1347 parent_tidptr, newtls, child_tidptr); 1348 if (tid != 0) 1349 return tid; 1350 fn(arg); 1351 internal_syscall(SYSCALL(exit), 0); 1352 } 1353 #elif defined(__aarch64__) 1354 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1355 int *parent_tidptr, void *newtls, int *child_tidptr) { 1356 long long res; 1357 if (!fn || !child_stack) 1358 return -EINVAL; 1359 CHECK_EQ(0, (uptr)child_stack % 16); 1360 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1361 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1362 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1363 1364 register int (*__fn)(void *) __asm__("x0") = fn; 1365 register void *__stack __asm__("x1") = child_stack; 1366 register int __flags __asm__("x2") = flags; 1367 register void *__arg __asm__("x3") = arg; 1368 register int *__ptid __asm__("x4") = parent_tidptr; 1369 register void *__tls __asm__("x5") = newtls; 1370 register int *__ctid __asm__("x6") = child_tidptr; 1371 1372 __asm__ __volatile__( 1373 "mov x0,x2\n" /* flags */ 1374 "mov x2,x4\n" /* ptid */ 1375 "mov x3,x5\n" /* tls */ 1376 "mov x4,x6\n" /* ctid */ 1377 "mov x8,%9\n" /* clone */ 1378 1379 "svc 0x0\n" 1380 1381 /* if (%r0 != 0) 1382 * return %r0; 1383 */ 1384 "cmp x0, #0\n" 1385 "bne 1f\n" 1386 1387 /* In the child, now. Call "fn(arg)". */ 1388 "ldp x1, x0, [sp], #16\n" 1389 "blr x1\n" 1390 1391 /* Call _exit(%r0). */ 1392 "mov x8, %10\n" 1393 "svc 0x0\n" 1394 "1:\n" 1395 1396 : "=r" (res) 1397 : "i"(-EINVAL), 1398 "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg), 1399 "r"(__ptid), "r"(__tls), "r"(__ctid), 1400 "i"(__NR_clone), "i"(__NR_exit) 1401 : "x30", "memory"); 1402 return res; 1403 } 1404 #elif defined(__powerpc64__) 1405 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1406 int *parent_tidptr, void *newtls, int *child_tidptr) { 1407 long long res; 1408 // Stack frame structure. 1409 #if SANITIZER_PPC64V1 1410 // Back chain == 0 (SP + 112) 1411 // Frame (112 bytes): 1412 // Parameter save area (SP + 48), 8 doublewords 1413 // TOC save area (SP + 40) 1414 // Link editor doubleword (SP + 32) 1415 // Compiler doubleword (SP + 24) 1416 // LR save area (SP + 16) 1417 // CR save area (SP + 8) 1418 // Back chain (SP + 0) 1419 # define FRAME_SIZE 112 1420 # define FRAME_TOC_SAVE_OFFSET 40 1421 #elif SANITIZER_PPC64V2 1422 // Back chain == 0 (SP + 32) 1423 // Frame (32 bytes): 1424 // TOC save area (SP + 24) 1425 // LR save area (SP + 16) 1426 // CR save area (SP + 8) 1427 // Back chain (SP + 0) 1428 # define FRAME_SIZE 32 1429 # define FRAME_TOC_SAVE_OFFSET 24 1430 #else 1431 # error "Unsupported PPC64 ABI" 1432 #endif 1433 if (!fn || !child_stack) 1434 return -EINVAL; 1435 CHECK_EQ(0, (uptr)child_stack % 16); 1436 1437 register int (*__fn)(void *) __asm__("r3") = fn; 1438 register void *__cstack __asm__("r4") = child_stack; 1439 register int __flags __asm__("r5") = flags; 1440 register void *__arg __asm__("r6") = arg; 1441 register int *__ptidptr __asm__("r7") = parent_tidptr; 1442 register void *__newtls __asm__("r8") = newtls; 1443 register int *__ctidptr __asm__("r9") = child_tidptr; 1444 1445 __asm__ __volatile__( 1446 /* fn and arg are saved across the syscall */ 1447 "mr 28, %5\n\t" 1448 "mr 27, %8\n\t" 1449 1450 /* syscall 1451 r0 == __NR_clone 1452 r3 == flags 1453 r4 == child_stack 1454 r5 == parent_tidptr 1455 r6 == newtls 1456 r7 == child_tidptr */ 1457 "mr 3, %7\n\t" 1458 "mr 5, %9\n\t" 1459 "mr 6, %10\n\t" 1460 "mr 7, %11\n\t" 1461 "li 0, %3\n\t" 1462 "sc\n\t" 1463 1464 /* Test if syscall was successful */ 1465 "cmpdi cr1, 3, 0\n\t" 1466 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t" 1467 "bne- cr1, 1f\n\t" 1468 1469 /* Set up stack frame */ 1470 "li 29, 0\n\t" 1471 "stdu 29, -8(1)\n\t" 1472 "stdu 1, -%12(1)\n\t" 1473 /* Do the function call */ 1474 "std 2, %13(1)\n\t" 1475 #if SANITIZER_PPC64V1 1476 "ld 0, 0(28)\n\t" 1477 "ld 2, 8(28)\n\t" 1478 "mtctr 0\n\t" 1479 #elif SANITIZER_PPC64V2 1480 "mr 12, 28\n\t" 1481 "mtctr 12\n\t" 1482 #else 1483 # error "Unsupported PPC64 ABI" 1484 #endif 1485 "mr 3, 27\n\t" 1486 "bctrl\n\t" 1487 "ld 2, %13(1)\n\t" 1488 1489 /* Call _exit(r3) */ 1490 "li 0, %4\n\t" 1491 "sc\n\t" 1492 1493 /* Return to parent */ 1494 "1:\n\t" 1495 "mr %0, 3\n\t" 1496 : "=r" (res) 1497 : "0" (-1), 1498 "i" (EINVAL), 1499 "i" (__NR_clone), 1500 "i" (__NR_exit), 1501 "r" (__fn), 1502 "r" (__cstack), 1503 "r" (__flags), 1504 "r" (__arg), 1505 "r" (__ptidptr), 1506 "r" (__newtls), 1507 "r" (__ctidptr), 1508 "i" (FRAME_SIZE), 1509 "i" (FRAME_TOC_SAVE_OFFSET) 1510 : "cr0", "cr1", "memory", "ctr", "r0", "r27", "r28", "r29"); 1511 return res; 1512 } 1513 #elif defined(__i386__) && SANITIZER_LINUX 1514 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1515 int *parent_tidptr, void *newtls, int *child_tidptr) { 1516 int res; 1517 if (!fn || !child_stack) 1518 return -EINVAL; 1519 CHECK_EQ(0, (uptr)child_stack % 16); 1520 child_stack = (char *)child_stack - 7 * sizeof(unsigned int); 1521 ((unsigned int *)child_stack)[0] = (uptr)flags; 1522 ((unsigned int *)child_stack)[1] = (uptr)0; 1523 ((unsigned int *)child_stack)[2] = (uptr)fn; 1524 ((unsigned int *)child_stack)[3] = (uptr)arg; 1525 __asm__ __volatile__( 1526 /* %eax = syscall(%eax = SYSCALL(clone), 1527 * %ebx = flags, 1528 * %ecx = child_stack, 1529 * %edx = parent_tidptr, 1530 * %esi = new_tls, 1531 * %edi = child_tidptr) 1532 */ 1533 1534 /* Obtain flags */ 1535 "movl (%%ecx), %%ebx\n" 1536 /* Do the system call */ 1537 "pushl %%ebx\n" 1538 "pushl %%esi\n" 1539 "pushl %%edi\n" 1540 /* Remember the flag value. */ 1541 "movl %%ebx, (%%ecx)\n" 1542 "int $0x80\n" 1543 "popl %%edi\n" 1544 "popl %%esi\n" 1545 "popl %%ebx\n" 1546 1547 /* if (%eax != 0) 1548 * return; 1549 */ 1550 1551 "test %%eax,%%eax\n" 1552 "jnz 1f\n" 1553 1554 /* terminate the stack frame */ 1555 "xorl %%ebp,%%ebp\n" 1556 /* Call FN. */ 1557 "call *%%ebx\n" 1558 #ifdef PIC 1559 "call here\n" 1560 "here:\n" 1561 "popl %%ebx\n" 1562 "addl $_GLOBAL_OFFSET_TABLE_+[.-here], %%ebx\n" 1563 #endif 1564 /* Call exit */ 1565 "movl %%eax, %%ebx\n" 1566 "movl %2, %%eax\n" 1567 "int $0x80\n" 1568 "1:\n" 1569 : "=a" (res) 1570 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1571 "c"(child_stack), 1572 "d"(parent_tidptr), 1573 "S"(newtls), 1574 "D"(child_tidptr) 1575 : "memory"); 1576 return res; 1577 } 1578 #elif defined(__arm__) && SANITIZER_LINUX 1579 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1580 int *parent_tidptr, void *newtls, int *child_tidptr) { 1581 unsigned int res; 1582 if (!fn || !child_stack) 1583 return -EINVAL; 1584 child_stack = (char *)child_stack - 2 * sizeof(unsigned int); 1585 ((unsigned int *)child_stack)[0] = (uptr)fn; 1586 ((unsigned int *)child_stack)[1] = (uptr)arg; 1587 register int r0 __asm__("r0") = flags; 1588 register void *r1 __asm__("r1") = child_stack; 1589 register int *r2 __asm__("r2") = parent_tidptr; 1590 register void *r3 __asm__("r3") = newtls; 1591 register int *r4 __asm__("r4") = child_tidptr; 1592 register int r7 __asm__("r7") = __NR_clone; 1593 1594 #if __ARM_ARCH > 4 || defined (__ARM_ARCH_4T__) 1595 # define ARCH_HAS_BX 1596 #endif 1597 #if __ARM_ARCH > 4 1598 # define ARCH_HAS_BLX 1599 #endif 1600 1601 #ifdef ARCH_HAS_BX 1602 # ifdef ARCH_HAS_BLX 1603 # define BLX(R) "blx " #R "\n" 1604 # else 1605 # define BLX(R) "mov lr, pc; bx " #R "\n" 1606 # endif 1607 #else 1608 # define BLX(R) "mov lr, pc; mov pc," #R "\n" 1609 #endif 1610 1611 __asm__ __volatile__( 1612 /* %r0 = syscall(%r7 = SYSCALL(clone), 1613 * %r0 = flags, 1614 * %r1 = child_stack, 1615 * %r2 = parent_tidptr, 1616 * %r3 = new_tls, 1617 * %r4 = child_tidptr) 1618 */ 1619 1620 /* Do the system call */ 1621 "swi 0x0\n" 1622 1623 /* if (%r0 != 0) 1624 * return %r0; 1625 */ 1626 "cmp r0, #0\n" 1627 "bne 1f\n" 1628 1629 /* In the child, now. Call "fn(arg)". */ 1630 "ldr r0, [sp, #4]\n" 1631 "ldr ip, [sp], #8\n" 1632 BLX(ip) 1633 /* Call _exit(%r0). */ 1634 "mov r7, %7\n" 1635 "swi 0x0\n" 1636 "1:\n" 1637 "mov %0, r0\n" 1638 : "=r"(res) 1639 : "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r7), 1640 "i"(__NR_exit) 1641 : "memory"); 1642 return res; 1643 } 1644 #endif // defined(__x86_64__) && SANITIZER_LINUX 1645 1646 #if SANITIZER_LINUX 1647 int internal_uname(struct utsname *buf) { 1648 return internal_syscall(SYSCALL(uname), buf); 1649 } 1650 #endif 1651 1652 #if SANITIZER_ANDROID 1653 #if __ANDROID_API__ < 21 1654 extern "C" __attribute__((weak)) int dl_iterate_phdr( 1655 int (*)(struct dl_phdr_info *, size_t, void *), void *); 1656 #endif 1657 1658 static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size, 1659 void *data) { 1660 // Any name starting with "lib" indicates a bug in L where library base names 1661 // are returned instead of paths. 1662 if (info->dlpi_name && info->dlpi_name[0] == 'l' && 1663 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') { 1664 *(bool *)data = true; 1665 return 1; 1666 } 1667 return 0; 1668 } 1669 1670 static atomic_uint32_t android_api_level; 1671 1672 static AndroidApiLevel AndroidDetectApiLevelStatic() { 1673 #if __ANDROID_API__ <= 19 1674 return ANDROID_KITKAT; 1675 #elif __ANDROID_API__ <= 22 1676 return ANDROID_LOLLIPOP_MR1; 1677 #else 1678 return ANDROID_POST_LOLLIPOP; 1679 #endif 1680 } 1681 1682 static AndroidApiLevel AndroidDetectApiLevel() { 1683 if (!&dl_iterate_phdr) 1684 return ANDROID_KITKAT; // K or lower 1685 bool base_name_seen = false; 1686 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen); 1687 if (base_name_seen) 1688 return ANDROID_LOLLIPOP_MR1; // L MR1 1689 return ANDROID_POST_LOLLIPOP; // post-L 1690 // Plain L (API level 21) is completely broken wrt ASan and not very 1691 // interesting to detect. 1692 } 1693 1694 extern "C" __attribute__((weak)) void* _DYNAMIC; 1695 1696 AndroidApiLevel AndroidGetApiLevel() { 1697 AndroidApiLevel level = 1698 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed); 1699 if (level) return level; 1700 level = &_DYNAMIC == nullptr ? AndroidDetectApiLevelStatic() 1701 : AndroidDetectApiLevel(); 1702 atomic_store(&android_api_level, level, memory_order_relaxed); 1703 return level; 1704 } 1705 1706 #endif 1707 1708 static HandleSignalMode GetHandleSignalModeImpl(int signum) { 1709 switch (signum) { 1710 case SIGABRT: 1711 return common_flags()->handle_abort; 1712 case SIGILL: 1713 return common_flags()->handle_sigill; 1714 case SIGTRAP: 1715 return common_flags()->handle_sigtrap; 1716 case SIGFPE: 1717 return common_flags()->handle_sigfpe; 1718 case SIGSEGV: 1719 return common_flags()->handle_segv; 1720 case SIGBUS: 1721 return common_flags()->handle_sigbus; 1722 } 1723 return kHandleSignalNo; 1724 } 1725 1726 HandleSignalMode GetHandleSignalMode(int signum) { 1727 HandleSignalMode result = GetHandleSignalModeImpl(signum); 1728 if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler) 1729 return kHandleSignalExclusive; 1730 return result; 1731 } 1732 1733 #if !SANITIZER_GO 1734 void *internal_start_thread(void *(*func)(void *arg), void *arg) { 1735 // Start the thread with signals blocked, otherwise it can steal user signals. 1736 __sanitizer_sigset_t set, old; 1737 internal_sigfillset(&set); 1738 #if SANITIZER_LINUX && !SANITIZER_ANDROID 1739 // Glibc uses SIGSETXID signal during setuid call. If this signal is blocked 1740 // on any thread, setuid call hangs (see test/tsan/setuid.c). 1741 internal_sigdelset(&set, 33); 1742 #endif 1743 internal_sigprocmask(SIG_SETMASK, &set, &old); 1744 void *th; 1745 real_pthread_create(&th, nullptr, func, arg); 1746 internal_sigprocmask(SIG_SETMASK, &old, nullptr); 1747 return th; 1748 } 1749 1750 void internal_join_thread(void *th) { 1751 real_pthread_join(th, nullptr); 1752 } 1753 #else 1754 void *internal_start_thread(void *(*func)(void *), void *arg) { return 0; } 1755 1756 void internal_join_thread(void *th) {} 1757 #endif 1758 1759 #if defined(__aarch64__) 1760 // Android headers in the older NDK releases miss this definition. 1761 struct __sanitizer_esr_context { 1762 struct _aarch64_ctx head; 1763 uint64_t esr; 1764 }; 1765 1766 static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) { 1767 static const u32 kEsrMagic = 0x45535201; 1768 u8 *aux = ucontext->uc_mcontext.__reserved; 1769 while (true) { 1770 _aarch64_ctx *ctx = (_aarch64_ctx *)aux; 1771 if (ctx->size == 0) break; 1772 if (ctx->magic == kEsrMagic) { 1773 *esr = ((__sanitizer_esr_context *)ctx)->esr; 1774 return true; 1775 } 1776 aux += ctx->size; 1777 } 1778 return false; 1779 } 1780 #endif 1781 1782 using Context = ucontext_t; 1783 1784 SignalContext::WriteFlag SignalContext::GetWriteFlag() const { 1785 Context *ucontext = (Context *)context; 1786 #if defined(__x86_64__) || defined(__i386__) 1787 static const uptr PF_WRITE = 1U << 1; 1788 #if SANITIZER_FREEBSD 1789 uptr err = ucontext->uc_mcontext.mc_err; 1790 #elif SANITIZER_NETBSD 1791 uptr err = ucontext->uc_mcontext.__gregs[_REG_ERR]; 1792 #elif SANITIZER_SOLARIS && defined(__i386__) 1793 const int Err = 13; 1794 uptr err = ucontext->uc_mcontext.gregs[Err]; 1795 #else 1796 uptr err = ucontext->uc_mcontext.gregs[REG_ERR]; 1797 #endif // SANITIZER_FREEBSD 1798 return err & PF_WRITE ? WRITE : READ; 1799 #elif defined(__mips__) 1800 uint32_t *exception_source; 1801 uint32_t faulty_instruction; 1802 uint32_t op_code; 1803 1804 exception_source = (uint32_t *)ucontext->uc_mcontext.pc; 1805 faulty_instruction = (uint32_t)(*exception_source); 1806 1807 op_code = (faulty_instruction >> 26) & 0x3f; 1808 1809 // FIXME: Add support for FPU, microMIPS, DSP, MSA memory instructions. 1810 switch (op_code) { 1811 case 0x28: // sb 1812 case 0x29: // sh 1813 case 0x2b: // sw 1814 case 0x3f: // sd 1815 #if __mips_isa_rev < 6 1816 case 0x2c: // sdl 1817 case 0x2d: // sdr 1818 case 0x2a: // swl 1819 case 0x2e: // swr 1820 #endif 1821 return SignalContext::WRITE; 1822 1823 case 0x20: // lb 1824 case 0x24: // lbu 1825 case 0x21: // lh 1826 case 0x25: // lhu 1827 case 0x23: // lw 1828 case 0x27: // lwu 1829 case 0x37: // ld 1830 #if __mips_isa_rev < 6 1831 case 0x1a: // ldl 1832 case 0x1b: // ldr 1833 case 0x22: // lwl 1834 case 0x26: // lwr 1835 #endif 1836 return SignalContext::READ; 1837 #if __mips_isa_rev == 6 1838 case 0x3b: // pcrel 1839 op_code = (faulty_instruction >> 19) & 0x3; 1840 switch (op_code) { 1841 case 0x1: // lwpc 1842 case 0x2: // lwupc 1843 return SignalContext::READ; 1844 } 1845 #endif 1846 } 1847 return SignalContext::UNKNOWN; 1848 #elif defined(__arm__) 1849 static const uptr FSR_WRITE = 1U << 11; 1850 uptr fsr = ucontext->uc_mcontext.error_code; 1851 return fsr & FSR_WRITE ? WRITE : READ; 1852 #elif defined(__aarch64__) 1853 static const u64 ESR_ELx_WNR = 1U << 6; 1854 u64 esr; 1855 if (!Aarch64GetESR(ucontext, &esr)) return UNKNOWN; 1856 return esr & ESR_ELx_WNR ? WRITE : READ; 1857 #elif defined(__sparc__) 1858 // Decode the instruction to determine the access type. 1859 // From OpenSolaris $SRC/uts/sun4/os/trap.c (get_accesstype). 1860 #if SANITIZER_SOLARIS 1861 uptr pc = ucontext->uc_mcontext.gregs[REG_PC]; 1862 #else 1863 // Historical BSDism here. 1864 struct sigcontext *scontext = (struct sigcontext *)context; 1865 #if defined(__arch64__) 1866 uptr pc = scontext->sigc_regs.tpc; 1867 #else 1868 uptr pc = scontext->si_regs.pc; 1869 #endif 1870 #endif 1871 u32 instr = *(u32 *)pc; 1872 return (instr >> 21) & 1 ? WRITE: READ; 1873 #elif defined(__riscv) 1874 unsigned long pc = ucontext->uc_mcontext.__gregs[REG_PC]; 1875 unsigned faulty_instruction = *(uint16_t *)pc; 1876 1877 #if defined(__riscv_compressed) 1878 if ((faulty_instruction & 0x3) != 0x3) { // it's a compressed instruction 1879 // set op_bits to the instruction bits [1, 0, 15, 14, 13] 1880 unsigned op_bits = 1881 ((faulty_instruction & 0x3) << 3) | (faulty_instruction >> 13); 1882 unsigned rd = faulty_instruction & 0xF80; // bits 7-11, inclusive 1883 switch (op_bits) { 1884 case 0b10'010: // c.lwsp (rd != x0) 1885 #if __riscv_xlen == 64 1886 case 0b10'011: // c.ldsp (rd != x0) 1887 #endif 1888 return rd ? SignalContext::READ : SignalContext::UNKNOWN; 1889 case 0b00'010: // c.lw 1890 #if __riscv_flen >= 32 && __riscv_xlen == 32 1891 case 0b10'011: // c.flwsp 1892 #endif 1893 #if __riscv_flen >= 32 || __riscv_xlen == 64 1894 case 0b00'011: // c.flw / c.ld 1895 #endif 1896 #if __riscv_flen == 64 1897 case 0b00'001: // c.fld 1898 case 0b10'001: // c.fldsp 1899 #endif 1900 return SignalContext::READ; 1901 case 0b00'110: // c.sw 1902 case 0b10'110: // c.swsp 1903 #if __riscv_flen >= 32 || __riscv_xlen == 64 1904 case 0b00'111: // c.fsw / c.sd 1905 case 0b10'111: // c.fswsp / c.sdsp 1906 #endif 1907 #if __riscv_flen == 64 1908 case 0b00'101: // c.fsd 1909 case 0b10'101: // c.fsdsp 1910 #endif 1911 return SignalContext::WRITE; 1912 default: 1913 return SignalContext::UNKNOWN; 1914 } 1915 } 1916 #endif 1917 1918 unsigned opcode = faulty_instruction & 0x7f; // lower 7 bits 1919 unsigned funct3 = (faulty_instruction >> 12) & 0x7; // bits 12-14, inclusive 1920 switch (opcode) { 1921 case 0b0000011: // loads 1922 switch (funct3) { 1923 case 0b000: // lb 1924 case 0b001: // lh 1925 case 0b010: // lw 1926 #if __riscv_xlen == 64 1927 case 0b011: // ld 1928 #endif 1929 case 0b100: // lbu 1930 case 0b101: // lhu 1931 return SignalContext::READ; 1932 default: 1933 return SignalContext::UNKNOWN; 1934 } 1935 case 0b0100011: // stores 1936 switch (funct3) { 1937 case 0b000: // sb 1938 case 0b001: // sh 1939 case 0b010: // sw 1940 #if __riscv_xlen == 64 1941 case 0b011: // sd 1942 #endif 1943 return SignalContext::WRITE; 1944 default: 1945 return SignalContext::UNKNOWN; 1946 } 1947 #if __riscv_flen >= 32 1948 case 0b0000111: // floating-point loads 1949 switch (funct3) { 1950 case 0b010: // flw 1951 #if __riscv_flen == 64 1952 case 0b011: // fld 1953 #endif 1954 return SignalContext::READ; 1955 default: 1956 return SignalContext::UNKNOWN; 1957 } 1958 case 0b0100111: // floating-point stores 1959 switch (funct3) { 1960 case 0b010: // fsw 1961 #if __riscv_flen == 64 1962 case 0b011: // fsd 1963 #endif 1964 return SignalContext::WRITE; 1965 default: 1966 return SignalContext::UNKNOWN; 1967 } 1968 #endif 1969 default: 1970 return SignalContext::UNKNOWN; 1971 } 1972 #else 1973 (void)ucontext; 1974 return UNKNOWN; // FIXME: Implement. 1975 #endif 1976 } 1977 1978 bool SignalContext::IsTrueFaultingAddress() const { 1979 auto si = static_cast<const siginfo_t *>(siginfo); 1980 // SIGSEGV signals without a true fault address have si_code set to 128. 1981 return si->si_signo == SIGSEGV && si->si_code != 128; 1982 } 1983 1984 void SignalContext::DumpAllRegisters(void *context) { 1985 // FIXME: Implement this. 1986 } 1987 1988 static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) { 1989 #if SANITIZER_NETBSD 1990 // This covers all NetBSD architectures 1991 ucontext_t *ucontext = (ucontext_t *)context; 1992 *pc = _UC_MACHINE_PC(ucontext); 1993 *bp = _UC_MACHINE_FP(ucontext); 1994 *sp = _UC_MACHINE_SP(ucontext); 1995 #elif defined(__arm__) 1996 ucontext_t *ucontext = (ucontext_t*)context; 1997 *pc = ucontext->uc_mcontext.arm_pc; 1998 *bp = ucontext->uc_mcontext.arm_fp; 1999 *sp = ucontext->uc_mcontext.arm_sp; 2000 #elif defined(__aarch64__) 2001 ucontext_t *ucontext = (ucontext_t*)context; 2002 *pc = ucontext->uc_mcontext.pc; 2003 *bp = ucontext->uc_mcontext.regs[29]; 2004 *sp = ucontext->uc_mcontext.sp; 2005 #elif defined(__hppa__) 2006 ucontext_t *ucontext = (ucontext_t*)context; 2007 *pc = ucontext->uc_mcontext.sc_iaoq[0]; 2008 /* GCC uses %r3 whenever a frame pointer is needed. */ 2009 *bp = ucontext->uc_mcontext.sc_gr[3]; 2010 *sp = ucontext->uc_mcontext.sc_gr[30]; 2011 #elif defined(__x86_64__) 2012 # if SANITIZER_FREEBSD 2013 ucontext_t *ucontext = (ucontext_t*)context; 2014 *pc = ucontext->uc_mcontext.mc_rip; 2015 *bp = ucontext->uc_mcontext.mc_rbp; 2016 *sp = ucontext->uc_mcontext.mc_rsp; 2017 # else 2018 ucontext_t *ucontext = (ucontext_t*)context; 2019 *pc = ucontext->uc_mcontext.gregs[REG_RIP]; 2020 *bp = ucontext->uc_mcontext.gregs[REG_RBP]; 2021 *sp = ucontext->uc_mcontext.gregs[REG_RSP]; 2022 # endif 2023 #elif defined(__i386__) 2024 # if SANITIZER_FREEBSD 2025 ucontext_t *ucontext = (ucontext_t*)context; 2026 *pc = ucontext->uc_mcontext.mc_eip; 2027 *bp = ucontext->uc_mcontext.mc_ebp; 2028 *sp = ucontext->uc_mcontext.mc_esp; 2029 # else 2030 ucontext_t *ucontext = (ucontext_t*)context; 2031 # if SANITIZER_SOLARIS 2032 /* Use the numeric values: the symbolic ones are undefined by llvm 2033 include/llvm/Support/Solaris.h. */ 2034 # ifndef REG_EIP 2035 # define REG_EIP 14 // REG_PC 2036 # endif 2037 # ifndef REG_EBP 2038 # define REG_EBP 6 // REG_FP 2039 # endif 2040 # ifndef REG_UESP 2041 # define REG_UESP 17 // REG_SP 2042 # endif 2043 # endif 2044 *pc = ucontext->uc_mcontext.gregs[REG_EIP]; 2045 *bp = ucontext->uc_mcontext.gregs[REG_EBP]; 2046 *sp = ucontext->uc_mcontext.gregs[REG_UESP]; 2047 # endif 2048 #elif defined(__powerpc__) || defined(__powerpc64__) 2049 ucontext_t *ucontext = (ucontext_t*)context; 2050 *pc = ucontext->uc_mcontext.regs->nip; 2051 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1]; 2052 // The powerpc{,64}-linux ABIs do not specify r31 as the frame 2053 // pointer, but GCC always uses r31 when we need a frame pointer. 2054 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31]; 2055 #elif defined(__sparc__) 2056 #if defined(__arch64__) || defined(__sparcv9) 2057 #define STACK_BIAS 2047 2058 #else 2059 #define STACK_BIAS 0 2060 # endif 2061 # if SANITIZER_SOLARIS 2062 ucontext_t *ucontext = (ucontext_t *)context; 2063 *pc = ucontext->uc_mcontext.gregs[REG_PC]; 2064 *sp = ucontext->uc_mcontext.gregs[REG_O6] + STACK_BIAS; 2065 #else 2066 // Historical BSDism here. 2067 struct sigcontext *scontext = (struct sigcontext *)context; 2068 #if defined(__arch64__) 2069 *pc = scontext->sigc_regs.tpc; 2070 *sp = scontext->sigc_regs.u_regs[14] + STACK_BIAS; 2071 #else 2072 *pc = scontext->si_regs.pc; 2073 *sp = scontext->si_regs.u_regs[14]; 2074 #endif 2075 # endif 2076 *bp = (uptr)((uhwptr *)*sp)[14] + STACK_BIAS; 2077 #elif defined(__mips__) 2078 ucontext_t *ucontext = (ucontext_t*)context; 2079 *pc = ucontext->uc_mcontext.pc; 2080 *bp = ucontext->uc_mcontext.gregs[30]; 2081 *sp = ucontext->uc_mcontext.gregs[29]; 2082 #elif defined(__s390__) 2083 ucontext_t *ucontext = (ucontext_t*)context; 2084 # if defined(__s390x__) 2085 *pc = ucontext->uc_mcontext.psw.addr; 2086 # else 2087 *pc = ucontext->uc_mcontext.psw.addr & 0x7fffffff; 2088 # endif 2089 *bp = ucontext->uc_mcontext.gregs[11]; 2090 *sp = ucontext->uc_mcontext.gregs[15]; 2091 #elif defined(__riscv) 2092 ucontext_t *ucontext = (ucontext_t*)context; 2093 *pc = ucontext->uc_mcontext.__gregs[REG_PC]; 2094 *bp = ucontext->uc_mcontext.__gregs[REG_S0]; 2095 *sp = ucontext->uc_mcontext.__gregs[REG_SP]; 2096 #else 2097 # error "Unsupported arch" 2098 #endif 2099 } 2100 2101 void SignalContext::InitPcSpBp() { GetPcSpBp(context, &pc, &sp, &bp); } 2102 2103 void InitializePlatformEarly() { 2104 // Do nothing. 2105 } 2106 2107 void MaybeReexec() { 2108 // No need to re-exec on Linux. 2109 } 2110 2111 void CheckASLR() { 2112 #if SANITIZER_NETBSD 2113 int mib[3]; 2114 int paxflags; 2115 uptr len = sizeof(paxflags); 2116 2117 mib[0] = CTL_PROC; 2118 mib[1] = internal_getpid(); 2119 mib[2] = PROC_PID_PAXFLAGS; 2120 2121 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2122 Printf("sysctl failed\n"); 2123 Die(); 2124 } 2125 2126 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_ASLR)) { 2127 Printf("This sanitizer is not compatible with enabled ASLR.\n" 2128 "To disable ASLR, please run \"paxctl +a %s\" and try again.\n", 2129 GetArgv()[0]); 2130 Die(); 2131 } 2132 #elif SANITIZER_PPC64V2 2133 // Disable ASLR for Linux PPC64LE. 2134 int old_personality = personality(0xffffffff); 2135 if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) { 2136 VReport(1, "WARNING: Program is being run with address space layout " 2137 "randomization (ASLR) enabled which prevents the thread and " 2138 "memory sanitizers from working on powerpc64le.\n" 2139 "ASLR will be disabled and the program re-executed.\n"); 2140 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1); 2141 ReExec(); 2142 } 2143 #elif SANITIZER_FREEBSD 2144 int aslr_pie; 2145 uptr len = sizeof(aslr_pie); 2146 #if SANITIZER_WORDSIZE == 64 2147 if (UNLIKELY(internal_sysctlbyname("kern.elf64.aslr.pie_enable", 2148 &aslr_pie, &len, NULL, 0) == -1)) { 2149 // We're making things less 'dramatic' here since 2150 // the OID is not necessarily guaranteed to be here 2151 // just yet regarding FreeBSD release 2152 return; 2153 } 2154 2155 if (aslr_pie > 0) { 2156 Printf("This sanitizer is not compatible with enabled ASLR " 2157 "and binaries compiled with PIE\n"); 2158 Die(); 2159 } 2160 #endif 2161 // there might be 32 bits compat for 64 bits 2162 if (UNLIKELY(internal_sysctlbyname("kern.elf32.aslr.pie_enable", 2163 &aslr_pie, &len, NULL, 0) == -1)) { 2164 return; 2165 } 2166 2167 if (aslr_pie > 0) { 2168 Printf("This sanitizer is not compatible with enabled ASLR " 2169 "and binaries compiled with PIE\n"); 2170 Die(); 2171 } 2172 #else 2173 // Do nothing 2174 #endif 2175 } 2176 2177 void CheckMPROTECT() { 2178 #if SANITIZER_NETBSD 2179 int mib[3]; 2180 int paxflags; 2181 uptr len = sizeof(paxflags); 2182 2183 mib[0] = CTL_PROC; 2184 mib[1] = internal_getpid(); 2185 mib[2] = PROC_PID_PAXFLAGS; 2186 2187 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2188 Printf("sysctl failed\n"); 2189 Die(); 2190 } 2191 2192 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_MPROTECT)) { 2193 Printf("This sanitizer is not compatible with enabled MPROTECT\n"); 2194 Die(); 2195 } 2196 #else 2197 // Do nothing 2198 #endif 2199 } 2200 2201 void CheckNoDeepBind(const char *filename, int flag) { 2202 #ifdef RTLD_DEEPBIND 2203 if (flag & RTLD_DEEPBIND) { 2204 Report( 2205 "You are trying to dlopen a %s shared library with RTLD_DEEPBIND flag" 2206 " which is incompatible with sanitizer runtime " 2207 "(see https://github.com/google/sanitizers/issues/611 for details" 2208 "). If you want to run %s library under sanitizers please remove " 2209 "RTLD_DEEPBIND from dlopen flags.\n", 2210 filename, filename); 2211 Die(); 2212 } 2213 #endif 2214 } 2215 2216 uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding, 2217 uptr *largest_gap_found, 2218 uptr *max_occupied_addr) { 2219 UNREACHABLE("FindAvailableMemoryRange is not available"); 2220 return 0; 2221 } 2222 2223 bool GetRandom(void *buffer, uptr length, bool blocking) { 2224 if (!buffer || !length || length > 256) 2225 return false; 2226 #if SANITIZER_USE_GETENTROPY 2227 uptr rnd = getentropy(buffer, length); 2228 int rverrno = 0; 2229 if (internal_iserror(rnd, &rverrno) && rverrno == EFAULT) 2230 return false; 2231 else if (rnd == 0) 2232 return true; 2233 #endif // SANITIZER_USE_GETENTROPY 2234 2235 #if SANITIZER_USE_GETRANDOM 2236 static atomic_uint8_t skip_getrandom_syscall; 2237 if (!atomic_load_relaxed(&skip_getrandom_syscall)) { 2238 // Up to 256 bytes, getrandom will not be interrupted. 2239 uptr res = internal_syscall(SYSCALL(getrandom), buffer, length, 2240 blocking ? 0 : GRND_NONBLOCK); 2241 int rverrno = 0; 2242 if (internal_iserror(res, &rverrno) && rverrno == ENOSYS) 2243 atomic_store_relaxed(&skip_getrandom_syscall, 1); 2244 else if (res == length) 2245 return true; 2246 } 2247 #endif // SANITIZER_USE_GETRANDOM 2248 // Up to 256 bytes, a read off /dev/urandom will not be interrupted. 2249 // blocking is moot here, O_NONBLOCK has no effect when opening /dev/urandom. 2250 uptr fd = internal_open("/dev/urandom", O_RDONLY); 2251 if (internal_iserror(fd)) 2252 return false; 2253 uptr res = internal_read(fd, buffer, length); 2254 if (internal_iserror(res)) 2255 return false; 2256 internal_close(fd); 2257 return true; 2258 } 2259 2260 } // namespace __sanitizer 2261 2262 #endif 2263