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 void SetSigProcMask(__sanitizer_sigset_t *set, __sanitizer_sigset_t *old) { 154 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, set, old)); 155 } 156 157 ScopedBlockSignals::ScopedBlockSignals(__sanitizer_sigset_t *copy) { 158 __sanitizer_sigset_t set; 159 internal_sigfillset(&set); 160 # if SANITIZER_LINUX && !SANITIZER_ANDROID 161 // Glibc uses SIGSETXID signal during setuid call. If this signal is blocked 162 // on any thread, setuid call hangs. 163 // See test/sanitizer_common/TestCases/Linux/setuid.c. 164 internal_sigdelset(&set, 33); 165 # endif 166 SetSigProcMask(&set, &saved_); 167 if (copy) 168 internal_memcpy(copy, &saved_, sizeof(saved_)); 169 } 170 171 ScopedBlockSignals::~ScopedBlockSignals() { SetSigProcMask(&saved_, nullptr); } 172 173 # if SANITIZER_LINUX && defined(__x86_64__) 174 # include "sanitizer_syscall_linux_x86_64.inc" 175 # elif SANITIZER_LINUX && SANITIZER_RISCV64 176 # include "sanitizer_syscall_linux_riscv64.inc" 177 # elif SANITIZER_LINUX && defined(__aarch64__) 178 # include "sanitizer_syscall_linux_aarch64.inc" 179 # elif SANITIZER_LINUX && defined(__arm__) 180 # include "sanitizer_syscall_linux_arm.inc" 181 # elif SANITIZER_LINUX && defined(__hexagon__) 182 # include "sanitizer_syscall_linux_hexagon.inc" 183 # else 184 # include "sanitizer_syscall_generic.inc" 185 # endif 186 187 // --------------- sanitizer_libc.h 188 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 189 #if !SANITIZER_S390 190 uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd, 191 u64 offset) { 192 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 193 return internal_syscall(SYSCALL(mmap), (uptr)addr, length, prot, flags, fd, 194 offset); 195 #else 196 // mmap2 specifies file offset in 4096-byte units. 197 CHECK(IsAligned(offset, 4096)); 198 return internal_syscall(SYSCALL(mmap2), addr, length, prot, flags, fd, 199 offset / 4096); 200 #endif 201 } 202 #endif // !SANITIZER_S390 203 204 uptr internal_munmap(void *addr, uptr length) { 205 return internal_syscall(SYSCALL(munmap), (uptr)addr, length); 206 } 207 208 #if SANITIZER_LINUX 209 uptr internal_mremap(void *old_address, uptr old_size, uptr new_size, int flags, 210 void *new_address) { 211 return internal_syscall(SYSCALL(mremap), (uptr)old_address, old_size, 212 new_size, flags, (uptr)new_address); 213 } 214 #endif 215 216 int internal_mprotect(void *addr, uptr length, int prot) { 217 return internal_syscall(SYSCALL(mprotect), (uptr)addr, length, prot); 218 } 219 220 int internal_madvise(uptr addr, uptr length, int advice) { 221 return internal_syscall(SYSCALL(madvise), addr, length, advice); 222 } 223 224 uptr internal_close(fd_t fd) { 225 return internal_syscall(SYSCALL(close), fd); 226 } 227 228 uptr internal_open(const char *filename, int flags) { 229 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 230 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags); 231 #else 232 return internal_syscall(SYSCALL(open), (uptr)filename, flags); 233 #endif 234 } 235 236 uptr internal_open(const char *filename, int flags, u32 mode) { 237 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 238 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags, 239 mode); 240 #else 241 return internal_syscall(SYSCALL(open), (uptr)filename, flags, mode); 242 #endif 243 } 244 245 uptr internal_read(fd_t fd, void *buf, uptr count) { 246 sptr res; 247 HANDLE_EINTR(res, 248 (sptr)internal_syscall(SYSCALL(read), fd, (uptr)buf, count)); 249 return res; 250 } 251 252 uptr internal_write(fd_t fd, const void *buf, uptr count) { 253 sptr res; 254 HANDLE_EINTR(res, 255 (sptr)internal_syscall(SYSCALL(write), fd, (uptr)buf, count)); 256 return res; 257 } 258 259 uptr internal_ftruncate(fd_t fd, uptr size) { 260 sptr res; 261 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(ftruncate), fd, 262 (OFF_T)size)); 263 return res; 264 } 265 266 #if !SANITIZER_LINUX_USES_64BIT_SYSCALLS && SANITIZER_LINUX 267 static void stat64_to_stat(struct stat64 *in, struct stat *out) { 268 internal_memset(out, 0, sizeof(*out)); 269 out->st_dev = in->st_dev; 270 out->st_ino = in->st_ino; 271 out->st_mode = in->st_mode; 272 out->st_nlink = in->st_nlink; 273 out->st_uid = in->st_uid; 274 out->st_gid = in->st_gid; 275 out->st_rdev = in->st_rdev; 276 out->st_size = in->st_size; 277 out->st_blksize = in->st_blksize; 278 out->st_blocks = in->st_blocks; 279 out->st_atime = in->st_atime; 280 out->st_mtime = in->st_mtime; 281 out->st_ctime = in->st_ctime; 282 } 283 #endif 284 285 #if defined(__mips64) 286 // Undefine compatibility macros from <sys/stat.h> 287 // so that they would not clash with the kernel_stat 288 // st_[a|m|c]time fields 289 #if !SANITIZER_GO 290 #undef st_atime 291 #undef st_mtime 292 #undef st_ctime 293 #endif 294 #if defined(SANITIZER_ANDROID) 295 // Bionic sys/stat.h defines additional macros 296 // for compatibility with the old NDKs and 297 // they clash with the kernel_stat structure 298 // st_[a|m|c]time_nsec fields. 299 #undef st_atime_nsec 300 #undef st_mtime_nsec 301 #undef st_ctime_nsec 302 #endif 303 static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) { 304 internal_memset(out, 0, sizeof(*out)); 305 out->st_dev = in->st_dev; 306 out->st_ino = in->st_ino; 307 out->st_mode = in->st_mode; 308 out->st_nlink = in->st_nlink; 309 out->st_uid = in->st_uid; 310 out->st_gid = in->st_gid; 311 out->st_rdev = in->st_rdev; 312 out->st_size = in->st_size; 313 out->st_blksize = in->st_blksize; 314 out->st_blocks = in->st_blocks; 315 #if defined(__USE_MISC) || \ 316 defined(__USE_XOPEN2K8) || \ 317 defined(SANITIZER_ANDROID) 318 out->st_atim.tv_sec = in->st_atime; 319 out->st_atim.tv_nsec = in->st_atime_nsec; 320 out->st_mtim.tv_sec = in->st_mtime; 321 out->st_mtim.tv_nsec = in->st_mtime_nsec; 322 out->st_ctim.tv_sec = in->st_ctime; 323 out->st_ctim.tv_nsec = in->st_ctime_nsec; 324 #else 325 out->st_atime = in->st_atime; 326 out->st_atimensec = in->st_atime_nsec; 327 out->st_mtime = in->st_mtime; 328 out->st_mtimensec = in->st_mtime_nsec; 329 out->st_ctime = in->st_ctime; 330 out->st_atimensec = in->st_ctime_nsec; 331 #endif 332 } 333 #endif 334 335 uptr internal_stat(const char *path, void *buf) { 336 #if SANITIZER_FREEBSD 337 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 0); 338 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 339 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 340 0); 341 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 342 # if defined(__mips64) 343 // For mips64, stat syscall fills buffer in the format of kernel_stat 344 struct kernel_stat kbuf; 345 int res = internal_syscall(SYSCALL(stat), path, &kbuf); 346 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 347 return res; 348 # else 349 return internal_syscall(SYSCALL(stat), (uptr)path, (uptr)buf); 350 # endif 351 #else 352 struct stat64 buf64; 353 int res = internal_syscall(SYSCALL(stat64), path, &buf64); 354 stat64_to_stat(&buf64, (struct stat *)buf); 355 return res; 356 #endif 357 } 358 359 uptr internal_lstat(const char *path, void *buf) { 360 #if SANITIZER_FREEBSD 361 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 362 AT_SYMLINK_NOFOLLOW); 363 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 364 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 365 AT_SYMLINK_NOFOLLOW); 366 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 367 # if SANITIZER_MIPS64 368 // For mips64, lstat syscall fills buffer in the format of kernel_stat 369 struct kernel_stat kbuf; 370 int res = internal_syscall(SYSCALL(lstat), path, &kbuf); 371 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 372 return res; 373 # else 374 return internal_syscall(SYSCALL(lstat), (uptr)path, (uptr)buf); 375 # endif 376 #else 377 struct stat64 buf64; 378 int res = internal_syscall(SYSCALL(lstat64), path, &buf64); 379 stat64_to_stat(&buf64, (struct stat *)buf); 380 return res; 381 #endif 382 } 383 384 uptr internal_fstat(fd_t fd, void *buf) { 385 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 386 #if SANITIZER_MIPS64 387 // For mips64, fstat syscall fills buffer in the format of kernel_stat 388 struct kernel_stat kbuf; 389 int res = internal_syscall(SYSCALL(fstat), fd, &kbuf); 390 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 391 return res; 392 # else 393 return internal_syscall(SYSCALL(fstat), fd, (uptr)buf); 394 # endif 395 #else 396 struct stat64 buf64; 397 int res = internal_syscall(SYSCALL(fstat64), fd, &buf64); 398 stat64_to_stat(&buf64, (struct stat *)buf); 399 return res; 400 #endif 401 } 402 403 uptr internal_filesize(fd_t fd) { 404 struct stat st; 405 if (internal_fstat(fd, &st)) 406 return -1; 407 return (uptr)st.st_size; 408 } 409 410 uptr internal_dup(int oldfd) { 411 return internal_syscall(SYSCALL(dup), oldfd); 412 } 413 414 uptr internal_dup2(int oldfd, int newfd) { 415 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 416 return internal_syscall(SYSCALL(dup3), oldfd, newfd, 0); 417 #else 418 return internal_syscall(SYSCALL(dup2), oldfd, newfd); 419 #endif 420 } 421 422 uptr internal_readlink(const char *path, char *buf, uptr bufsize) { 423 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 424 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD, (uptr)path, (uptr)buf, 425 bufsize); 426 #else 427 return internal_syscall(SYSCALL(readlink), (uptr)path, (uptr)buf, bufsize); 428 #endif 429 } 430 431 uptr internal_unlink(const char *path) { 432 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 433 return internal_syscall(SYSCALL(unlinkat), AT_FDCWD, (uptr)path, 0); 434 #else 435 return internal_syscall(SYSCALL(unlink), (uptr)path); 436 #endif 437 } 438 439 uptr internal_rename(const char *oldpath, const char *newpath) { 440 #if defined(__riscv) && defined(__linux__) 441 return internal_syscall(SYSCALL(renameat2), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 442 (uptr)newpath, 0); 443 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 444 return internal_syscall(SYSCALL(renameat), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 445 (uptr)newpath); 446 #else 447 return internal_syscall(SYSCALL(rename), (uptr)oldpath, (uptr)newpath); 448 #endif 449 } 450 451 uptr internal_sched_yield() { 452 return internal_syscall(SYSCALL(sched_yield)); 453 } 454 455 void internal_usleep(u64 useconds) { 456 struct timespec ts; 457 ts.tv_sec = useconds / 1000000; 458 ts.tv_nsec = (useconds % 1000000) * 1000; 459 internal_syscall(SYSCALL(nanosleep), &ts, &ts); 460 } 461 462 uptr internal_execve(const char *filename, char *const argv[], 463 char *const envp[]) { 464 return internal_syscall(SYSCALL(execve), (uptr)filename, (uptr)argv, 465 (uptr)envp); 466 } 467 #endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD 468 469 #if !SANITIZER_NETBSD 470 void internal__exit(int exitcode) { 471 #if SANITIZER_FREEBSD || SANITIZER_SOLARIS 472 internal_syscall(SYSCALL(exit), exitcode); 473 #else 474 internal_syscall(SYSCALL(exit_group), exitcode); 475 #endif 476 Die(); // Unreachable. 477 } 478 #endif // !SANITIZER_NETBSD 479 480 // ----------------- sanitizer_common.h 481 bool FileExists(const char *filename) { 482 if (ShouldMockFailureToOpen(filename)) 483 return false; 484 struct stat st; 485 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 486 if (internal_syscall(SYSCALL(newfstatat), AT_FDCWD, filename, &st, 0)) 487 #else 488 if (internal_stat(filename, &st)) 489 #endif 490 return false; 491 // Sanity check: filename is a regular file. 492 return S_ISREG(st.st_mode); 493 } 494 495 #if !SANITIZER_NETBSD 496 tid_t GetTid() { 497 #if SANITIZER_FREEBSD 498 long Tid; 499 thr_self(&Tid); 500 return Tid; 501 #elif SANITIZER_SOLARIS 502 return thr_self(); 503 #else 504 return internal_syscall(SYSCALL(gettid)); 505 #endif 506 } 507 508 int TgKill(pid_t pid, tid_t tid, int sig) { 509 #if SANITIZER_LINUX 510 return internal_syscall(SYSCALL(tgkill), pid, tid, sig); 511 #elif SANITIZER_FREEBSD 512 return internal_syscall(SYSCALL(thr_kill2), pid, tid, sig); 513 #elif SANITIZER_SOLARIS 514 (void)pid; 515 return thr_kill(tid, sig); 516 #endif 517 } 518 #endif 519 520 #if SANITIZER_GLIBC 521 u64 NanoTime() { 522 kernel_timeval tv; 523 internal_memset(&tv, 0, sizeof(tv)); 524 internal_syscall(SYSCALL(gettimeofday), &tv, 0); 525 return (u64)tv.tv_sec * 1000 * 1000 * 1000 + tv.tv_usec * 1000; 526 } 527 // Used by real_clock_gettime. 528 uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) { 529 return internal_syscall(SYSCALL(clock_gettime), clk_id, tp); 530 } 531 #elif !SANITIZER_SOLARIS && !SANITIZER_NETBSD 532 u64 NanoTime() { 533 struct timespec ts; 534 clock_gettime(CLOCK_REALTIME, &ts); 535 return (u64)ts.tv_sec * 1000 * 1000 * 1000 + ts.tv_nsec; 536 } 537 #endif 538 539 // Like getenv, but reads env directly from /proc (on Linux) or parses the 540 // 'environ' array (on some others) and does not use libc. This function 541 // should be called first inside __asan_init. 542 const char *GetEnv(const char *name) { 543 #if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_SOLARIS 544 if (::environ != 0) { 545 uptr NameLen = internal_strlen(name); 546 for (char **Env = ::environ; *Env != 0; Env++) { 547 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=') 548 return (*Env) + NameLen + 1; 549 } 550 } 551 return 0; // Not found. 552 #elif SANITIZER_LINUX 553 static char *environ; 554 static uptr len; 555 static bool inited; 556 if (!inited) { 557 inited = true; 558 uptr environ_size; 559 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len)) 560 environ = nullptr; 561 } 562 if (!environ || len == 0) return nullptr; 563 uptr namelen = internal_strlen(name); 564 const char *p = environ; 565 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer 566 // proc file has the format NAME=value\0NAME=value\0NAME=value\0... 567 const char* endp = 568 (char*)internal_memchr(p, '\0', len - (p - environ)); 569 if (!endp) // this entry isn't NUL terminated 570 return nullptr; 571 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match. 572 return p + namelen + 1; // point after = 573 p = endp + 1; 574 } 575 return nullptr; // Not found. 576 #else 577 #error "Unsupported platform" 578 #endif 579 } 580 581 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD && !SANITIZER_GO 582 extern "C" { 583 SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end; 584 } 585 #endif 586 587 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD 588 static void ReadNullSepFileToArray(const char *path, char ***arr, 589 int arr_size) { 590 char *buff; 591 uptr buff_size; 592 uptr buff_len; 593 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray"); 594 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) { 595 (*arr)[0] = nullptr; 596 return; 597 } 598 (*arr)[0] = buff; 599 int count, i; 600 for (count = 1, i = 1; ; i++) { 601 if (buff[i] == 0) { 602 if (buff[i+1] == 0) break; 603 (*arr)[count] = &buff[i+1]; 604 CHECK_LE(count, arr_size - 1); // FIXME: make this more flexible. 605 count++; 606 } 607 } 608 (*arr)[count] = nullptr; 609 } 610 #endif 611 612 static void GetArgsAndEnv(char ***argv, char ***envp) { 613 #if SANITIZER_FREEBSD 614 // On FreeBSD, retrieving the argument and environment arrays is done via the 615 // kern.ps_strings sysctl, which returns a pointer to a structure containing 616 // this information. See also <sys/exec.h>. 617 ps_strings *pss; 618 uptr sz = sizeof(pss); 619 if (internal_sysctlbyname("kern.ps_strings", &pss, &sz, NULL, 0) == -1) { 620 Printf("sysctl kern.ps_strings failed\n"); 621 Die(); 622 } 623 *argv = pss->ps_argvstr; 624 *envp = pss->ps_envstr; 625 #elif SANITIZER_NETBSD 626 *argv = __ps_strings->ps_argvstr; 627 *envp = __ps_strings->ps_envstr; 628 #else // SANITIZER_FREEBSD 629 #if !SANITIZER_GO 630 if (&__libc_stack_end) { 631 uptr* stack_end = (uptr*)__libc_stack_end; 632 // Normally argc can be obtained from *stack_end, however, on ARM glibc's 633 // _start clobbers it: 634 // https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/arm/start.S;hb=refs/heads/release/2.31/master#l75 635 // Do not special-case ARM and infer argc from argv everywhere. 636 int argc = 0; 637 while (stack_end[argc + 1]) argc++; 638 *argv = (char**)(stack_end + 1); 639 *envp = (char**)(stack_end + argc + 2); 640 } else { 641 #endif // !SANITIZER_GO 642 static const int kMaxArgv = 2000, kMaxEnvp = 2000; 643 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv); 644 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp); 645 #if !SANITIZER_GO 646 } 647 #endif // !SANITIZER_GO 648 #endif // SANITIZER_FREEBSD 649 } 650 651 char **GetArgv() { 652 char **argv, **envp; 653 GetArgsAndEnv(&argv, &envp); 654 return argv; 655 } 656 657 char **GetEnviron() { 658 char **argv, **envp; 659 GetArgsAndEnv(&argv, &envp); 660 return envp; 661 } 662 663 #if !SANITIZER_SOLARIS 664 void FutexWait(atomic_uint32_t *p, u32 cmp) { 665 # if SANITIZER_FREEBSD 666 _umtx_op(p, UMTX_OP_WAIT_UINT, cmp, 0, 0); 667 # elif SANITIZER_NETBSD 668 sched_yield(); /* No userspace futex-like synchronization */ 669 # else 670 internal_syscall(SYSCALL(futex), (uptr)p, FUTEX_WAIT_PRIVATE, cmp, 0, 0, 0); 671 # endif 672 } 673 674 void FutexWake(atomic_uint32_t *p, u32 count) { 675 # if SANITIZER_FREEBSD 676 _umtx_op(p, UMTX_OP_WAKE, count, 0, 0); 677 # elif SANITIZER_NETBSD 678 /* No userspace futex-like synchronization */ 679 # else 680 internal_syscall(SYSCALL(futex), (uptr)p, FUTEX_WAKE_PRIVATE, count, 0, 0, 0); 681 # endif 682 } 683 684 # endif // !SANITIZER_SOLARIS 685 686 // ----------------- sanitizer_linux.h 687 // The actual size of this structure is specified by d_reclen. 688 // Note that getdents64 uses a different structure format. We only provide the 689 // 32-bit syscall here. 690 #if SANITIZER_NETBSD 691 // Not used 692 #else 693 struct linux_dirent { 694 #if SANITIZER_X32 || defined(__aarch64__) || SANITIZER_RISCV64 695 u64 d_ino; 696 u64 d_off; 697 #else 698 unsigned long d_ino; 699 unsigned long d_off; 700 #endif 701 unsigned short d_reclen; 702 #if defined(__aarch64__) || SANITIZER_RISCV64 703 unsigned char d_type; 704 #endif 705 char d_name[256]; 706 }; 707 #endif 708 709 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 710 // Syscall wrappers. 711 uptr internal_ptrace(int request, int pid, void *addr, void *data) { 712 return internal_syscall(SYSCALL(ptrace), request, pid, (uptr)addr, 713 (uptr)data); 714 } 715 716 uptr internal_waitpid(int pid, int *status, int options) { 717 return internal_syscall(SYSCALL(wait4), pid, (uptr)status, options, 718 0 /* rusage */); 719 } 720 721 uptr internal_getpid() { 722 return internal_syscall(SYSCALL(getpid)); 723 } 724 725 uptr internal_getppid() { 726 return internal_syscall(SYSCALL(getppid)); 727 } 728 729 int internal_dlinfo(void *handle, int request, void *p) { 730 #if SANITIZER_FREEBSD 731 return dlinfo(handle, request, p); 732 #else 733 UNIMPLEMENTED(); 734 #endif 735 } 736 737 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) { 738 #if SANITIZER_FREEBSD 739 return internal_syscall(SYSCALL(getdirentries), fd, (uptr)dirp, count, NULL); 740 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 741 return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count); 742 #else 743 return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count); 744 #endif 745 } 746 747 uptr internal_lseek(fd_t fd, OFF_T offset, int whence) { 748 return internal_syscall(SYSCALL(lseek), fd, offset, whence); 749 } 750 751 #if SANITIZER_LINUX 752 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) { 753 return internal_syscall(SYSCALL(prctl), option, arg2, arg3, arg4, arg5); 754 } 755 #endif 756 757 uptr internal_sigaltstack(const void *ss, void *oss) { 758 return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss); 759 } 760 761 int internal_fork() { 762 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 763 return internal_syscall(SYSCALL(clone), SIGCHLD, 0); 764 #else 765 return internal_syscall(SYSCALL(fork)); 766 #endif 767 } 768 769 #if SANITIZER_FREEBSD 770 int internal_sysctl(const int *name, unsigned int namelen, void *oldp, 771 uptr *oldlenp, const void *newp, uptr newlen) { 772 return internal_syscall(SYSCALL(__sysctl), name, namelen, oldp, 773 (size_t *)oldlenp, newp, (size_t)newlen); 774 } 775 776 int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp, 777 const void *newp, uptr newlen) { 778 // Note: this function can be called during startup, so we need to avoid 779 // calling any interceptable functions. On FreeBSD >= 1300045 sysctlbyname() 780 // is a real syscall, but for older versions it calls sysctlnametomib() 781 // followed by sysctl(). To avoid calling the intercepted version and 782 // asserting if this happens during startup, call the real sysctlnametomib() 783 // followed by internal_sysctl() if the syscall is not available. 784 #ifdef SYS___sysctlbyname 785 return internal_syscall(SYSCALL(__sysctlbyname), sname, 786 internal_strlen(sname), oldp, (size_t *)oldlenp, newp, 787 (size_t)newlen); 788 #else 789 static decltype(sysctlnametomib) *real_sysctlnametomib = nullptr; 790 if (!real_sysctlnametomib) 791 real_sysctlnametomib = 792 (decltype(sysctlnametomib) *)dlsym(RTLD_NEXT, "sysctlnametomib"); 793 CHECK(real_sysctlnametomib); 794 795 int oid[CTL_MAXNAME]; 796 size_t len = CTL_MAXNAME; 797 if (real_sysctlnametomib(sname, oid, &len) == -1) 798 return (-1); 799 return internal_sysctl(oid, len, oldp, oldlenp, newp, newlen); 800 #endif 801 } 802 #endif 803 804 #if SANITIZER_LINUX 805 #define SA_RESTORER 0x04000000 806 // Doesn't set sa_restorer if the caller did not set it, so use with caution 807 //(see below). 808 int internal_sigaction_norestorer(int signum, const void *act, void *oldact) { 809 __sanitizer_kernel_sigaction_t k_act, k_oldact; 810 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t)); 811 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t)); 812 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act; 813 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact; 814 if (u_act) { 815 k_act.handler = u_act->handler; 816 k_act.sigaction = u_act->sigaction; 817 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask, 818 sizeof(__sanitizer_kernel_sigset_t)); 819 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL). 820 k_act.sa_flags = u_act->sa_flags | SA_RESTORER; 821 // FIXME: most often sa_restorer is unset, however the kernel requires it 822 // to point to a valid signal restorer that calls the rt_sigreturn syscall. 823 // If sa_restorer passed to the kernel is NULL, the program may crash upon 824 // signal delivery or fail to unwind the stack in the signal handler. 825 // libc implementation of sigaction() passes its own restorer to 826 // rt_sigaction, so we need to do the same (we'll need to reimplement the 827 // restorers; for x86_64 the restorer address can be obtained from 828 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact). 829 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 830 k_act.sa_restorer = u_act->sa_restorer; 831 #endif 832 } 833 834 uptr result = internal_syscall(SYSCALL(rt_sigaction), (uptr)signum, 835 (uptr)(u_act ? &k_act : nullptr), 836 (uptr)(u_oldact ? &k_oldact : nullptr), 837 (uptr)sizeof(__sanitizer_kernel_sigset_t)); 838 839 if ((result == 0) && u_oldact) { 840 u_oldact->handler = k_oldact.handler; 841 u_oldact->sigaction = k_oldact.sigaction; 842 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask, 843 sizeof(__sanitizer_kernel_sigset_t)); 844 u_oldact->sa_flags = k_oldact.sa_flags; 845 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 846 u_oldact->sa_restorer = k_oldact.sa_restorer; 847 #endif 848 } 849 return result; 850 } 851 #endif // SANITIZER_LINUX 852 853 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set, 854 __sanitizer_sigset_t *oldset) { 855 #if SANITIZER_FREEBSD 856 return internal_syscall(SYSCALL(sigprocmask), how, set, oldset); 857 #else 858 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 859 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset; 860 return internal_syscall(SYSCALL(rt_sigprocmask), (uptr)how, (uptr)k_set, 861 (uptr)k_oldset, sizeof(__sanitizer_kernel_sigset_t)); 862 #endif 863 } 864 865 void internal_sigfillset(__sanitizer_sigset_t *set) { 866 internal_memset(set, 0xff, sizeof(*set)); 867 } 868 869 void internal_sigemptyset(__sanitizer_sigset_t *set) { 870 internal_memset(set, 0, sizeof(*set)); 871 } 872 873 #if SANITIZER_LINUX 874 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 875 signum -= 1; 876 CHECK_GE(signum, 0); 877 CHECK_LT(signum, sizeof(*set) * 8); 878 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 879 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 880 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 881 k_set->sig[idx] &= ~((uptr)1 << bit); 882 } 883 884 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 885 signum -= 1; 886 CHECK_GE(signum, 0); 887 CHECK_LT(signum, sizeof(*set) * 8); 888 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 889 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 890 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 891 return k_set->sig[idx] & ((uptr)1 << bit); 892 } 893 #elif SANITIZER_FREEBSD 894 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 895 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 896 sigdelset(rset, signum); 897 } 898 899 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 900 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 901 return sigismember(rset, signum); 902 } 903 #endif 904 #endif // !SANITIZER_SOLARIS 905 906 #if !SANITIZER_NETBSD 907 // ThreadLister implementation. 908 ThreadLister::ThreadLister(pid_t pid) : pid_(pid), buffer_(4096) { 909 char task_directory_path[80]; 910 internal_snprintf(task_directory_path, sizeof(task_directory_path), 911 "/proc/%d/task/", pid); 912 descriptor_ = internal_open(task_directory_path, O_RDONLY | O_DIRECTORY); 913 if (internal_iserror(descriptor_)) { 914 Report("Can't open /proc/%d/task for reading.\n", pid); 915 } 916 } 917 918 ThreadLister::Result ThreadLister::ListThreads( 919 InternalMmapVector<tid_t> *threads) { 920 if (internal_iserror(descriptor_)) 921 return Error; 922 internal_lseek(descriptor_, 0, SEEK_SET); 923 threads->clear(); 924 925 Result result = Ok; 926 for (bool first_read = true;; first_read = false) { 927 // Resize to max capacity if it was downsized by IsAlive. 928 buffer_.resize(buffer_.capacity()); 929 CHECK_GE(buffer_.size(), 4096); 930 uptr read = internal_getdents( 931 descriptor_, (struct linux_dirent *)buffer_.data(), buffer_.size()); 932 if (!read) 933 return result; 934 if (internal_iserror(read)) { 935 Report("Can't read directory entries from /proc/%d/task.\n", pid_); 936 return Error; 937 } 938 939 for (uptr begin = (uptr)buffer_.data(), end = begin + read; begin < end;) { 940 struct linux_dirent *entry = (struct linux_dirent *)begin; 941 begin += entry->d_reclen; 942 if (entry->d_ino == 1) { 943 // Inode 1 is for bad blocks and also can be a reason for early return. 944 // Should be emitted if kernel tried to output terminating thread. 945 // See proc_task_readdir implementation in Linux. 946 result = Incomplete; 947 } 948 if (entry->d_ino && *entry->d_name >= '0' && *entry->d_name <= '9') 949 threads->push_back(internal_atoll(entry->d_name)); 950 } 951 952 // Now we are going to detect short-read or early EOF. In such cases Linux 953 // can return inconsistent list with missing alive threads. 954 // Code will just remember that the list can be incomplete but it will 955 // continue reads to return as much as possible. 956 if (!first_read) { 957 // The first one was a short-read by definition. 958 result = Incomplete; 959 } else if (read > buffer_.size() - 1024) { 960 // Read was close to the buffer size. So double the size and assume the 961 // worst. 962 buffer_.resize(buffer_.size() * 2); 963 result = Incomplete; 964 } else if (!threads->empty() && !IsAlive(threads->back())) { 965 // Maybe Linux early returned from read on terminated thread (!pid_alive) 966 // and failed to restore read position. 967 // See next_tid and proc_task_instantiate in Linux. 968 result = Incomplete; 969 } 970 } 971 } 972 973 bool ThreadLister::IsAlive(int tid) { 974 // /proc/%d/task/%d/status uses same call to detect alive threads as 975 // proc_task_readdir. See task_state implementation in Linux. 976 char path[80]; 977 internal_snprintf(path, sizeof(path), "/proc/%d/task/%d/status", pid_, tid); 978 if (!ReadFileToVector(path, &buffer_) || buffer_.empty()) 979 return false; 980 buffer_.push_back(0); 981 static const char kPrefix[] = "\nPPid:"; 982 const char *field = internal_strstr(buffer_.data(), kPrefix); 983 if (!field) 984 return false; 985 field += internal_strlen(kPrefix); 986 return (int)internal_atoll(field) != 0; 987 } 988 989 ThreadLister::~ThreadLister() { 990 if (!internal_iserror(descriptor_)) 991 internal_close(descriptor_); 992 } 993 #endif 994 995 #if SANITIZER_WORDSIZE == 32 996 // Take care of unusable kernel area in top gigabyte. 997 static uptr GetKernelAreaSize() { 998 #if SANITIZER_LINUX && !SANITIZER_X32 999 const uptr gbyte = 1UL << 30; 1000 1001 // Firstly check if there are writable segments 1002 // mapped to top gigabyte (e.g. stack). 1003 MemoryMappingLayout proc_maps(/*cache_enabled*/true); 1004 if (proc_maps.Error()) 1005 return 0; 1006 MemoryMappedSegment segment; 1007 while (proc_maps.Next(&segment)) { 1008 if ((segment.end >= 3 * gbyte) && segment.IsWritable()) return 0; 1009 } 1010 1011 #if !SANITIZER_ANDROID 1012 // Even if nothing is mapped, top Gb may still be accessible 1013 // if we are running on 64-bit kernel. 1014 // Uname may report misleading results if personality type 1015 // is modified (e.g. under schroot) so check this as well. 1016 struct utsname uname_info; 1017 int pers = personality(0xffffffffUL); 1018 if (!(pers & PER_MASK) && internal_uname(&uname_info) == 0 && 1019 internal_strstr(uname_info.machine, "64")) 1020 return 0; 1021 #endif // SANITIZER_ANDROID 1022 1023 // Top gigabyte is reserved for kernel. 1024 return gbyte; 1025 #else 1026 return 0; 1027 #endif // SANITIZER_LINUX && !SANITIZER_X32 1028 } 1029 #endif // SANITIZER_WORDSIZE == 32 1030 1031 uptr GetMaxVirtualAddress() { 1032 #if SANITIZER_NETBSD && defined(__x86_64__) 1033 return 0x7f7ffffff000ULL; // (0x00007f8000000000 - PAGE_SIZE) 1034 #elif SANITIZER_WORDSIZE == 64 1035 # if defined(__powerpc64__) || defined(__aarch64__) 1036 // On PowerPC64 we have two different address space layouts: 44- and 46-bit. 1037 // We somehow need to figure out which one we are using now and choose 1038 // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL. 1039 // Note that with 'ulimit -s unlimited' the stack is moved away from the top 1040 // of the address space, so simply checking the stack address is not enough. 1041 // This should (does) work for both PowerPC64 Endian modes. 1042 // Similarly, aarch64 has multiple address space layouts: 39, 42 and 47-bit. 1043 return (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1)) - 1; 1044 #elif SANITIZER_RISCV64 1045 return (1ULL << 38) - 1; 1046 # elif defined(__mips64) 1047 return (1ULL << 40) - 1; // 0x000000ffffffffffUL; 1048 # elif defined(__s390x__) 1049 return (1ULL << 53) - 1; // 0x001fffffffffffffUL; 1050 #elif defined(__sparc__) 1051 return ~(uptr)0; 1052 # else 1053 return (1ULL << 47) - 1; // 0x00007fffffffffffUL; 1054 # endif 1055 #else // SANITIZER_WORDSIZE == 32 1056 # if defined(__s390__) 1057 return (1ULL << 31) - 1; // 0x7fffffff; 1058 # else 1059 return (1ULL << 32) - 1; // 0xffffffff; 1060 # endif 1061 #endif // SANITIZER_WORDSIZE 1062 } 1063 1064 uptr GetMaxUserVirtualAddress() { 1065 uptr addr = GetMaxVirtualAddress(); 1066 #if SANITIZER_WORDSIZE == 32 && !defined(__s390__) 1067 if (!common_flags()->full_address_space) 1068 addr -= GetKernelAreaSize(); 1069 CHECK_LT(reinterpret_cast<uptr>(&addr), addr); 1070 #endif 1071 return addr; 1072 } 1073 1074 #if !SANITIZER_ANDROID 1075 uptr GetPageSize() { 1076 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__i386__)) && \ 1077 defined(EXEC_PAGESIZE) 1078 return EXEC_PAGESIZE; 1079 #elif SANITIZER_FREEBSD || SANITIZER_NETBSD 1080 // Use sysctl as sysconf can trigger interceptors internally. 1081 int pz = 0; 1082 uptr pzl = sizeof(pz); 1083 int mib[2] = {CTL_HW, HW_PAGESIZE}; 1084 int rv = internal_sysctl(mib, 2, &pz, &pzl, nullptr, 0); 1085 CHECK_EQ(rv, 0); 1086 return (uptr)pz; 1087 #elif SANITIZER_USE_GETAUXVAL 1088 return getauxval(AT_PAGESZ); 1089 #else 1090 return sysconf(_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy. 1091 #endif 1092 } 1093 #endif // !SANITIZER_ANDROID 1094 1095 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) { 1096 #if SANITIZER_SOLARIS 1097 const char *default_module_name = getexecname(); 1098 CHECK_NE(default_module_name, NULL); 1099 return internal_snprintf(buf, buf_len, "%s", default_module_name); 1100 #else 1101 #if SANITIZER_FREEBSD || SANITIZER_NETBSD 1102 #if SANITIZER_FREEBSD 1103 const int Mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1}; 1104 #else 1105 const int Mib[4] = {CTL_KERN, KERN_PROC_ARGS, -1, KERN_PROC_PATHNAME}; 1106 #endif 1107 const char *default_module_name = "kern.proc.pathname"; 1108 uptr Size = buf_len; 1109 bool IsErr = 1110 (internal_sysctl(Mib, ARRAY_SIZE(Mib), buf, &Size, NULL, 0) != 0); 1111 int readlink_error = IsErr ? errno : 0; 1112 uptr module_name_len = Size; 1113 #else 1114 const char *default_module_name = "/proc/self/exe"; 1115 uptr module_name_len = internal_readlink( 1116 default_module_name, buf, buf_len); 1117 int readlink_error; 1118 bool IsErr = internal_iserror(module_name_len, &readlink_error); 1119 #endif // SANITIZER_SOLARIS 1120 if (IsErr) { 1121 // We can't read binary name for some reason, assume it's unknown. 1122 Report("WARNING: reading executable name failed with errno %d, " 1123 "some stack frames may not be symbolized\n", readlink_error); 1124 module_name_len = internal_snprintf(buf, buf_len, "%s", 1125 default_module_name); 1126 CHECK_LT(module_name_len, buf_len); 1127 } 1128 return module_name_len; 1129 #endif 1130 } 1131 1132 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) { 1133 #if SANITIZER_LINUX 1134 char *tmpbuf; 1135 uptr tmpsize; 1136 uptr tmplen; 1137 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen, 1138 1024 * 1024)) { 1139 internal_strncpy(buf, tmpbuf, buf_len); 1140 UnmapOrDie(tmpbuf, tmpsize); 1141 return internal_strlen(buf); 1142 } 1143 #endif 1144 return ReadBinaryName(buf, buf_len); 1145 } 1146 1147 // Match full names of the form /path/to/base_name{-,.}* 1148 bool LibraryNameIs(const char *full_name, const char *base_name) { 1149 const char *name = full_name; 1150 // Strip path. 1151 while (*name != '\0') name++; 1152 while (name > full_name && *name != '/') name--; 1153 if (*name == '/') name++; 1154 uptr base_name_length = internal_strlen(base_name); 1155 if (internal_strncmp(name, base_name, base_name_length)) return false; 1156 return (name[base_name_length] == '-' || name[base_name_length] == '.'); 1157 } 1158 1159 #if !SANITIZER_ANDROID 1160 // Call cb for each region mapped by map. 1161 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) { 1162 CHECK_NE(map, nullptr); 1163 #if !SANITIZER_FREEBSD 1164 typedef ElfW(Phdr) Elf_Phdr; 1165 typedef ElfW(Ehdr) Elf_Ehdr; 1166 #endif // !SANITIZER_FREEBSD 1167 char *base = (char *)map->l_addr; 1168 Elf_Ehdr *ehdr = (Elf_Ehdr *)base; 1169 char *phdrs = base + ehdr->e_phoff; 1170 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize; 1171 1172 // Find the segment with the minimum base so we can "relocate" the p_vaddr 1173 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC 1174 // objects have a non-zero base. 1175 uptr preferred_base = (uptr)-1; 1176 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1177 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1178 if (phdr->p_type == PT_LOAD && preferred_base > (uptr)phdr->p_vaddr) 1179 preferred_base = (uptr)phdr->p_vaddr; 1180 } 1181 1182 // Compute the delta from the real base to get a relocation delta. 1183 sptr delta = (uptr)base - preferred_base; 1184 // Now we can figure out what the loader really mapped. 1185 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1186 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1187 if (phdr->p_type == PT_LOAD) { 1188 uptr seg_start = phdr->p_vaddr + delta; 1189 uptr seg_end = seg_start + phdr->p_memsz; 1190 // None of these values are aligned. We consider the ragged edges of the 1191 // load command as defined, since they are mapped from the file. 1192 seg_start = RoundDownTo(seg_start, GetPageSizeCached()); 1193 seg_end = RoundUpTo(seg_end, GetPageSizeCached()); 1194 cb((void *)seg_start, seg_end - seg_start); 1195 } 1196 } 1197 } 1198 #endif 1199 1200 #if SANITIZER_LINUX 1201 #if defined(__x86_64__) 1202 // We cannot use glibc's clone wrapper, because it messes with the child 1203 // task's TLS. It writes the PID and TID of the child task to its thread 1204 // descriptor, but in our case the child task shares the thread descriptor with 1205 // the parent (because we don't know how to allocate a new thread 1206 // descriptor to keep glibc happy). So the stock version of clone(), when 1207 // used with CLONE_VM, would end up corrupting the parent's thread descriptor. 1208 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1209 int *parent_tidptr, void *newtls, int *child_tidptr) { 1210 long long res; 1211 if (!fn || !child_stack) 1212 return -EINVAL; 1213 CHECK_EQ(0, (uptr)child_stack % 16); 1214 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1215 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1216 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1217 register void *r8 __asm__("r8") = newtls; 1218 register int *r10 __asm__("r10") = child_tidptr; 1219 __asm__ __volatile__( 1220 /* %rax = syscall(%rax = SYSCALL(clone), 1221 * %rdi = flags, 1222 * %rsi = child_stack, 1223 * %rdx = parent_tidptr, 1224 * %r8 = new_tls, 1225 * %r10 = child_tidptr) 1226 */ 1227 "syscall\n" 1228 1229 /* if (%rax != 0) 1230 * return; 1231 */ 1232 "testq %%rax,%%rax\n" 1233 "jnz 1f\n" 1234 1235 /* In the child. Terminate unwind chain. */ 1236 // XXX: We should also terminate the CFI unwind chain 1237 // here. Unfortunately clang 3.2 doesn't support the 1238 // necessary CFI directives, so we skip that part. 1239 "xorq %%rbp,%%rbp\n" 1240 1241 /* Call "fn(arg)". */ 1242 "popq %%rax\n" 1243 "popq %%rdi\n" 1244 "call *%%rax\n" 1245 1246 /* Call _exit(%rax). */ 1247 "movq %%rax,%%rdi\n" 1248 "movq %2,%%rax\n" 1249 "syscall\n" 1250 1251 /* Return to parent. */ 1252 "1:\n" 1253 : "=a" (res) 1254 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1255 "S"(child_stack), 1256 "D"(flags), 1257 "d"(parent_tidptr), 1258 "r"(r8), 1259 "r"(r10) 1260 : "memory", "r11", "rcx"); 1261 return res; 1262 } 1263 #elif defined(__mips__) 1264 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1265 int *parent_tidptr, void *newtls, int *child_tidptr) { 1266 long long res; 1267 if (!fn || !child_stack) 1268 return -EINVAL; 1269 CHECK_EQ(0, (uptr)child_stack % 16); 1270 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1271 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1272 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1273 register void *a3 __asm__("$7") = newtls; 1274 register int *a4 __asm__("$8") = child_tidptr; 1275 // We don't have proper CFI directives here because it requires alot of code 1276 // for very marginal benefits. 1277 __asm__ __volatile__( 1278 /* $v0 = syscall($v0 = __NR_clone, 1279 * $a0 = flags, 1280 * $a1 = child_stack, 1281 * $a2 = parent_tidptr, 1282 * $a3 = new_tls, 1283 * $a4 = child_tidptr) 1284 */ 1285 ".cprestore 16;\n" 1286 "move $4,%1;\n" 1287 "move $5,%2;\n" 1288 "move $6,%3;\n" 1289 "move $7,%4;\n" 1290 /* Store the fifth argument on stack 1291 * if we are using 32-bit abi. 1292 */ 1293 #if SANITIZER_WORDSIZE == 32 1294 "lw %5,16($29);\n" 1295 #else 1296 "move $8,%5;\n" 1297 #endif 1298 "li $2,%6;\n" 1299 "syscall;\n" 1300 1301 /* if ($v0 != 0) 1302 * return; 1303 */ 1304 "bnez $2,1f;\n" 1305 1306 /* Call "fn(arg)". */ 1307 #if SANITIZER_WORDSIZE == 32 1308 #ifdef __BIG_ENDIAN__ 1309 "lw $25,4($29);\n" 1310 "lw $4,12($29);\n" 1311 #else 1312 "lw $25,0($29);\n" 1313 "lw $4,8($29);\n" 1314 #endif 1315 #else 1316 "ld $25,0($29);\n" 1317 "ld $4,8($29);\n" 1318 #endif 1319 "jal $25;\n" 1320 1321 /* Call _exit($v0). */ 1322 "move $4,$2;\n" 1323 "li $2,%7;\n" 1324 "syscall;\n" 1325 1326 /* Return to parent. */ 1327 "1:\n" 1328 : "=r" (res) 1329 : "r"(flags), 1330 "r"(child_stack), 1331 "r"(parent_tidptr), 1332 "r"(a3), 1333 "r"(a4), 1334 "i"(__NR_clone), 1335 "i"(__NR_exit) 1336 : "memory", "$29" ); 1337 return res; 1338 } 1339 #elif SANITIZER_RISCV64 1340 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1341 int *parent_tidptr, void *newtls, int *child_tidptr) { 1342 if (!fn || !child_stack) 1343 return -EINVAL; 1344 1345 CHECK_EQ(0, (uptr)child_stack % 16); 1346 1347 register int res __asm__("a0"); 1348 register int __flags __asm__("a0") = flags; 1349 register void *__stack __asm__("a1") = child_stack; 1350 register int *__ptid __asm__("a2") = parent_tidptr; 1351 register void *__tls __asm__("a3") = newtls; 1352 register int *__ctid __asm__("a4") = child_tidptr; 1353 register int (*__fn)(void *) __asm__("a5") = fn; 1354 register void *__arg __asm__("a6") = arg; 1355 register int nr_clone __asm__("a7") = __NR_clone; 1356 1357 __asm__ __volatile__( 1358 "ecall\n" 1359 1360 /* if (a0 != 0) 1361 * return a0; 1362 */ 1363 "bnez a0, 1f\n" 1364 1365 // In the child, now. Call "fn(arg)". 1366 "mv a0, a6\n" 1367 "jalr a5\n" 1368 1369 // Call _exit(a0). 1370 "addi a7, zero, %9\n" 1371 "ecall\n" 1372 "1:\n" 1373 1374 : "=r"(res) 1375 : "0"(__flags), "r"(__stack), "r"(__ptid), "r"(__tls), "r"(__ctid), 1376 "r"(__fn), "r"(__arg), "r"(nr_clone), "i"(__NR_exit) 1377 : "memory"); 1378 return res; 1379 } 1380 #elif defined(__aarch64__) 1381 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1382 int *parent_tidptr, void *newtls, int *child_tidptr) { 1383 long long res; 1384 if (!fn || !child_stack) 1385 return -EINVAL; 1386 CHECK_EQ(0, (uptr)child_stack % 16); 1387 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1388 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1389 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1390 1391 register int (*__fn)(void *) __asm__("x0") = fn; 1392 register void *__stack __asm__("x1") = child_stack; 1393 register int __flags __asm__("x2") = flags; 1394 register void *__arg __asm__("x3") = arg; 1395 register int *__ptid __asm__("x4") = parent_tidptr; 1396 register void *__tls __asm__("x5") = newtls; 1397 register int *__ctid __asm__("x6") = child_tidptr; 1398 1399 __asm__ __volatile__( 1400 "mov x0,x2\n" /* flags */ 1401 "mov x2,x4\n" /* ptid */ 1402 "mov x3,x5\n" /* tls */ 1403 "mov x4,x6\n" /* ctid */ 1404 "mov x8,%9\n" /* clone */ 1405 1406 "svc 0x0\n" 1407 1408 /* if (%r0 != 0) 1409 * return %r0; 1410 */ 1411 "cmp x0, #0\n" 1412 "bne 1f\n" 1413 1414 /* In the child, now. Call "fn(arg)". */ 1415 "ldp x1, x0, [sp], #16\n" 1416 "blr x1\n" 1417 1418 /* Call _exit(%r0). */ 1419 "mov x8, %10\n" 1420 "svc 0x0\n" 1421 "1:\n" 1422 1423 : "=r" (res) 1424 : "i"(-EINVAL), 1425 "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg), 1426 "r"(__ptid), "r"(__tls), "r"(__ctid), 1427 "i"(__NR_clone), "i"(__NR_exit) 1428 : "x30", "memory"); 1429 return res; 1430 } 1431 #elif defined(__powerpc64__) 1432 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1433 int *parent_tidptr, void *newtls, int *child_tidptr) { 1434 long long res; 1435 // Stack frame structure. 1436 #if SANITIZER_PPC64V1 1437 // Back chain == 0 (SP + 112) 1438 // Frame (112 bytes): 1439 // Parameter save area (SP + 48), 8 doublewords 1440 // TOC save area (SP + 40) 1441 // Link editor doubleword (SP + 32) 1442 // Compiler doubleword (SP + 24) 1443 // LR save area (SP + 16) 1444 // CR save area (SP + 8) 1445 // Back chain (SP + 0) 1446 # define FRAME_SIZE 112 1447 # define FRAME_TOC_SAVE_OFFSET 40 1448 #elif SANITIZER_PPC64V2 1449 // Back chain == 0 (SP + 32) 1450 // Frame (32 bytes): 1451 // TOC save area (SP + 24) 1452 // LR save area (SP + 16) 1453 // CR save area (SP + 8) 1454 // Back chain (SP + 0) 1455 # define FRAME_SIZE 32 1456 # define FRAME_TOC_SAVE_OFFSET 24 1457 #else 1458 # error "Unsupported PPC64 ABI" 1459 #endif 1460 if (!fn || !child_stack) 1461 return -EINVAL; 1462 CHECK_EQ(0, (uptr)child_stack % 16); 1463 1464 register int (*__fn)(void *) __asm__("r3") = fn; 1465 register void *__cstack __asm__("r4") = child_stack; 1466 register int __flags __asm__("r5") = flags; 1467 register void *__arg __asm__("r6") = arg; 1468 register int *__ptidptr __asm__("r7") = parent_tidptr; 1469 register void *__newtls __asm__("r8") = newtls; 1470 register int *__ctidptr __asm__("r9") = child_tidptr; 1471 1472 __asm__ __volatile__( 1473 /* fn and arg are saved across the syscall */ 1474 "mr 28, %5\n\t" 1475 "mr 27, %8\n\t" 1476 1477 /* syscall 1478 r0 == __NR_clone 1479 r3 == flags 1480 r4 == child_stack 1481 r5 == parent_tidptr 1482 r6 == newtls 1483 r7 == child_tidptr */ 1484 "mr 3, %7\n\t" 1485 "mr 5, %9\n\t" 1486 "mr 6, %10\n\t" 1487 "mr 7, %11\n\t" 1488 "li 0, %3\n\t" 1489 "sc\n\t" 1490 1491 /* Test if syscall was successful */ 1492 "cmpdi cr1, 3, 0\n\t" 1493 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t" 1494 "bne- cr1, 1f\n\t" 1495 1496 /* Set up stack frame */ 1497 "li 29, 0\n\t" 1498 "stdu 29, -8(1)\n\t" 1499 "stdu 1, -%12(1)\n\t" 1500 /* Do the function call */ 1501 "std 2, %13(1)\n\t" 1502 #if SANITIZER_PPC64V1 1503 "ld 0, 0(28)\n\t" 1504 "ld 2, 8(28)\n\t" 1505 "mtctr 0\n\t" 1506 #elif SANITIZER_PPC64V2 1507 "mr 12, 28\n\t" 1508 "mtctr 12\n\t" 1509 #else 1510 # error "Unsupported PPC64 ABI" 1511 #endif 1512 "mr 3, 27\n\t" 1513 "bctrl\n\t" 1514 "ld 2, %13(1)\n\t" 1515 1516 /* Call _exit(r3) */ 1517 "li 0, %4\n\t" 1518 "sc\n\t" 1519 1520 /* Return to parent */ 1521 "1:\n\t" 1522 "mr %0, 3\n\t" 1523 : "=r" (res) 1524 : "0" (-1), 1525 "i" (EINVAL), 1526 "i" (__NR_clone), 1527 "i" (__NR_exit), 1528 "r" (__fn), 1529 "r" (__cstack), 1530 "r" (__flags), 1531 "r" (__arg), 1532 "r" (__ptidptr), 1533 "r" (__newtls), 1534 "r" (__ctidptr), 1535 "i" (FRAME_SIZE), 1536 "i" (FRAME_TOC_SAVE_OFFSET) 1537 : "cr0", "cr1", "memory", "ctr", "r0", "r27", "r28", "r29"); 1538 return res; 1539 } 1540 #elif defined(__i386__) 1541 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1542 int *parent_tidptr, void *newtls, int *child_tidptr) { 1543 int res; 1544 if (!fn || !child_stack) 1545 return -EINVAL; 1546 CHECK_EQ(0, (uptr)child_stack % 16); 1547 child_stack = (char *)child_stack - 7 * sizeof(unsigned int); 1548 ((unsigned int *)child_stack)[0] = (uptr)flags; 1549 ((unsigned int *)child_stack)[1] = (uptr)0; 1550 ((unsigned int *)child_stack)[2] = (uptr)fn; 1551 ((unsigned int *)child_stack)[3] = (uptr)arg; 1552 __asm__ __volatile__( 1553 /* %eax = syscall(%eax = SYSCALL(clone), 1554 * %ebx = flags, 1555 * %ecx = child_stack, 1556 * %edx = parent_tidptr, 1557 * %esi = new_tls, 1558 * %edi = child_tidptr) 1559 */ 1560 1561 /* Obtain flags */ 1562 "movl (%%ecx), %%ebx\n" 1563 /* Do the system call */ 1564 "pushl %%ebx\n" 1565 "pushl %%esi\n" 1566 "pushl %%edi\n" 1567 /* Remember the flag value. */ 1568 "movl %%ebx, (%%ecx)\n" 1569 "int $0x80\n" 1570 "popl %%edi\n" 1571 "popl %%esi\n" 1572 "popl %%ebx\n" 1573 1574 /* if (%eax != 0) 1575 * return; 1576 */ 1577 1578 "test %%eax,%%eax\n" 1579 "jnz 1f\n" 1580 1581 /* terminate the stack frame */ 1582 "xorl %%ebp,%%ebp\n" 1583 /* Call FN. */ 1584 "call *%%ebx\n" 1585 #ifdef PIC 1586 "call here\n" 1587 "here:\n" 1588 "popl %%ebx\n" 1589 "addl $_GLOBAL_OFFSET_TABLE_+[.-here], %%ebx\n" 1590 #endif 1591 /* Call exit */ 1592 "movl %%eax, %%ebx\n" 1593 "movl %2, %%eax\n" 1594 "int $0x80\n" 1595 "1:\n" 1596 : "=a" (res) 1597 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1598 "c"(child_stack), 1599 "d"(parent_tidptr), 1600 "S"(newtls), 1601 "D"(child_tidptr) 1602 : "memory"); 1603 return res; 1604 } 1605 #elif defined(__arm__) 1606 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1607 int *parent_tidptr, void *newtls, int *child_tidptr) { 1608 unsigned int res; 1609 if (!fn || !child_stack) 1610 return -EINVAL; 1611 child_stack = (char *)child_stack - 2 * sizeof(unsigned int); 1612 ((unsigned int *)child_stack)[0] = (uptr)fn; 1613 ((unsigned int *)child_stack)[1] = (uptr)arg; 1614 register int r0 __asm__("r0") = flags; 1615 register void *r1 __asm__("r1") = child_stack; 1616 register int *r2 __asm__("r2") = parent_tidptr; 1617 register void *r3 __asm__("r3") = newtls; 1618 register int *r4 __asm__("r4") = child_tidptr; 1619 register int r7 __asm__("r7") = __NR_clone; 1620 1621 #if __ARM_ARCH > 4 || defined (__ARM_ARCH_4T__) 1622 # define ARCH_HAS_BX 1623 #endif 1624 #if __ARM_ARCH > 4 1625 # define ARCH_HAS_BLX 1626 #endif 1627 1628 #ifdef ARCH_HAS_BX 1629 # ifdef ARCH_HAS_BLX 1630 # define BLX(R) "blx " #R "\n" 1631 # else 1632 # define BLX(R) "mov lr, pc; bx " #R "\n" 1633 # endif 1634 #else 1635 # define BLX(R) "mov lr, pc; mov pc," #R "\n" 1636 #endif 1637 1638 __asm__ __volatile__( 1639 /* %r0 = syscall(%r7 = SYSCALL(clone), 1640 * %r0 = flags, 1641 * %r1 = child_stack, 1642 * %r2 = parent_tidptr, 1643 * %r3 = new_tls, 1644 * %r4 = child_tidptr) 1645 */ 1646 1647 /* Do the system call */ 1648 "swi 0x0\n" 1649 1650 /* if (%r0 != 0) 1651 * return %r0; 1652 */ 1653 "cmp r0, #0\n" 1654 "bne 1f\n" 1655 1656 /* In the child, now. Call "fn(arg)". */ 1657 "ldr r0, [sp, #4]\n" 1658 "ldr ip, [sp], #8\n" 1659 BLX(ip) 1660 /* Call _exit(%r0). */ 1661 "mov r7, %7\n" 1662 "swi 0x0\n" 1663 "1:\n" 1664 "mov %0, r0\n" 1665 : "=r"(res) 1666 : "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r7), 1667 "i"(__NR_exit) 1668 : "memory"); 1669 return res; 1670 } 1671 #endif 1672 #endif // SANITIZER_LINUX 1673 1674 #if SANITIZER_LINUX 1675 int internal_uname(struct utsname *buf) { 1676 return internal_syscall(SYSCALL(uname), buf); 1677 } 1678 #endif 1679 1680 #if SANITIZER_ANDROID 1681 #if __ANDROID_API__ < 21 1682 extern "C" __attribute__((weak)) int dl_iterate_phdr( 1683 int (*)(struct dl_phdr_info *, size_t, void *), void *); 1684 #endif 1685 1686 static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size, 1687 void *data) { 1688 // Any name starting with "lib" indicates a bug in L where library base names 1689 // are returned instead of paths. 1690 if (info->dlpi_name && info->dlpi_name[0] == 'l' && 1691 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') { 1692 *(bool *)data = true; 1693 return 1; 1694 } 1695 return 0; 1696 } 1697 1698 static atomic_uint32_t android_api_level; 1699 1700 static AndroidApiLevel AndroidDetectApiLevelStatic() { 1701 #if __ANDROID_API__ <= 19 1702 return ANDROID_KITKAT; 1703 #elif __ANDROID_API__ <= 22 1704 return ANDROID_LOLLIPOP_MR1; 1705 #else 1706 return ANDROID_POST_LOLLIPOP; 1707 #endif 1708 } 1709 1710 static AndroidApiLevel AndroidDetectApiLevel() { 1711 if (!&dl_iterate_phdr) 1712 return ANDROID_KITKAT; // K or lower 1713 bool base_name_seen = false; 1714 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen); 1715 if (base_name_seen) 1716 return ANDROID_LOLLIPOP_MR1; // L MR1 1717 return ANDROID_POST_LOLLIPOP; // post-L 1718 // Plain L (API level 21) is completely broken wrt ASan and not very 1719 // interesting to detect. 1720 } 1721 1722 extern "C" __attribute__((weak)) void* _DYNAMIC; 1723 1724 AndroidApiLevel AndroidGetApiLevel() { 1725 AndroidApiLevel level = 1726 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed); 1727 if (level) return level; 1728 level = &_DYNAMIC == nullptr ? AndroidDetectApiLevelStatic() 1729 : AndroidDetectApiLevel(); 1730 atomic_store(&android_api_level, level, memory_order_relaxed); 1731 return level; 1732 } 1733 1734 #endif 1735 1736 static HandleSignalMode GetHandleSignalModeImpl(int signum) { 1737 switch (signum) { 1738 case SIGABRT: 1739 return common_flags()->handle_abort; 1740 case SIGILL: 1741 return common_flags()->handle_sigill; 1742 case SIGTRAP: 1743 return common_flags()->handle_sigtrap; 1744 case SIGFPE: 1745 return common_flags()->handle_sigfpe; 1746 case SIGSEGV: 1747 return common_flags()->handle_segv; 1748 case SIGBUS: 1749 return common_flags()->handle_sigbus; 1750 } 1751 return kHandleSignalNo; 1752 } 1753 1754 HandleSignalMode GetHandleSignalMode(int signum) { 1755 HandleSignalMode result = GetHandleSignalModeImpl(signum); 1756 if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler) 1757 return kHandleSignalExclusive; 1758 return result; 1759 } 1760 1761 #if !SANITIZER_GO 1762 void *internal_start_thread(void *(*func)(void *arg), void *arg) { 1763 // Start the thread with signals blocked, otherwise it can steal user signals. 1764 ScopedBlockSignals block(nullptr); 1765 void *th; 1766 real_pthread_create(&th, nullptr, func, arg); 1767 return th; 1768 } 1769 1770 void internal_join_thread(void *th) { 1771 real_pthread_join(th, nullptr); 1772 } 1773 #else 1774 void *internal_start_thread(void *(*func)(void *), void *arg) { return 0; } 1775 1776 void internal_join_thread(void *th) {} 1777 #endif 1778 1779 #if defined(__aarch64__) 1780 // Android headers in the older NDK releases miss this definition. 1781 struct __sanitizer_esr_context { 1782 struct _aarch64_ctx head; 1783 uint64_t esr; 1784 }; 1785 1786 static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) { 1787 static const u32 kEsrMagic = 0x45535201; 1788 u8 *aux = reinterpret_cast<u8 *>(ucontext->uc_mcontext.__reserved); 1789 while (true) { 1790 _aarch64_ctx *ctx = (_aarch64_ctx *)aux; 1791 if (ctx->size == 0) break; 1792 if (ctx->magic == kEsrMagic) { 1793 *esr = ((__sanitizer_esr_context *)ctx)->esr; 1794 return true; 1795 } 1796 aux += ctx->size; 1797 } 1798 return false; 1799 } 1800 #endif 1801 1802 using Context = ucontext_t; 1803 1804 SignalContext::WriteFlag SignalContext::GetWriteFlag() const { 1805 Context *ucontext = (Context *)context; 1806 #if defined(__x86_64__) || defined(__i386__) 1807 static const uptr PF_WRITE = 1U << 1; 1808 #if SANITIZER_FREEBSD 1809 uptr err = ucontext->uc_mcontext.mc_err; 1810 #elif SANITIZER_NETBSD 1811 uptr err = ucontext->uc_mcontext.__gregs[_REG_ERR]; 1812 #elif SANITIZER_SOLARIS && defined(__i386__) 1813 const int Err = 13; 1814 uptr err = ucontext->uc_mcontext.gregs[Err]; 1815 #else 1816 uptr err = ucontext->uc_mcontext.gregs[REG_ERR]; 1817 #endif // SANITIZER_FREEBSD 1818 return err & PF_WRITE ? WRITE : READ; 1819 #elif defined(__mips__) 1820 uint32_t *exception_source; 1821 uint32_t faulty_instruction; 1822 uint32_t op_code; 1823 1824 exception_source = (uint32_t *)ucontext->uc_mcontext.pc; 1825 faulty_instruction = (uint32_t)(*exception_source); 1826 1827 op_code = (faulty_instruction >> 26) & 0x3f; 1828 1829 // FIXME: Add support for FPU, microMIPS, DSP, MSA memory instructions. 1830 switch (op_code) { 1831 case 0x28: // sb 1832 case 0x29: // sh 1833 case 0x2b: // sw 1834 case 0x3f: // sd 1835 #if __mips_isa_rev < 6 1836 case 0x2c: // sdl 1837 case 0x2d: // sdr 1838 case 0x2a: // swl 1839 case 0x2e: // swr 1840 #endif 1841 return SignalContext::WRITE; 1842 1843 case 0x20: // lb 1844 case 0x24: // lbu 1845 case 0x21: // lh 1846 case 0x25: // lhu 1847 case 0x23: // lw 1848 case 0x27: // lwu 1849 case 0x37: // ld 1850 #if __mips_isa_rev < 6 1851 case 0x1a: // ldl 1852 case 0x1b: // ldr 1853 case 0x22: // lwl 1854 case 0x26: // lwr 1855 #endif 1856 return SignalContext::READ; 1857 #if __mips_isa_rev == 6 1858 case 0x3b: // pcrel 1859 op_code = (faulty_instruction >> 19) & 0x3; 1860 switch (op_code) { 1861 case 0x1: // lwpc 1862 case 0x2: // lwupc 1863 return SignalContext::READ; 1864 } 1865 #endif 1866 } 1867 return SignalContext::UNKNOWN; 1868 #elif defined(__arm__) 1869 static const uptr FSR_WRITE = 1U << 11; 1870 uptr fsr = ucontext->uc_mcontext.error_code; 1871 return fsr & FSR_WRITE ? WRITE : READ; 1872 #elif defined(__aarch64__) 1873 static const u64 ESR_ELx_WNR = 1U << 6; 1874 u64 esr; 1875 if (!Aarch64GetESR(ucontext, &esr)) return UNKNOWN; 1876 return esr & ESR_ELx_WNR ? WRITE : READ; 1877 #elif defined(__sparc__) 1878 // Decode the instruction to determine the access type. 1879 // From OpenSolaris $SRC/uts/sun4/os/trap.c (get_accesstype). 1880 #if SANITIZER_SOLARIS 1881 uptr pc = ucontext->uc_mcontext.gregs[REG_PC]; 1882 #else 1883 // Historical BSDism here. 1884 struct sigcontext *scontext = (struct sigcontext *)context; 1885 #if defined(__arch64__) 1886 uptr pc = scontext->sigc_regs.tpc; 1887 #else 1888 uptr pc = scontext->si_regs.pc; 1889 #endif 1890 #endif 1891 u32 instr = *(u32 *)pc; 1892 return (instr >> 21) & 1 ? WRITE: READ; 1893 #elif defined(__riscv) 1894 #if SANITIZER_FREEBSD 1895 unsigned long pc = ucontext->uc_mcontext.mc_gpregs.gp_sepc; 1896 #else 1897 unsigned long pc = ucontext->uc_mcontext.__gregs[REG_PC]; 1898 #endif 1899 unsigned faulty_instruction = *(uint16_t *)pc; 1900 1901 #if defined(__riscv_compressed) 1902 if ((faulty_instruction & 0x3) != 0x3) { // it's a compressed instruction 1903 // set op_bits to the instruction bits [1, 0, 15, 14, 13] 1904 unsigned op_bits = 1905 ((faulty_instruction & 0x3) << 3) | (faulty_instruction >> 13); 1906 unsigned rd = faulty_instruction & 0xF80; // bits 7-11, inclusive 1907 switch (op_bits) { 1908 case 0b10'010: // c.lwsp (rd != x0) 1909 #if __riscv_xlen == 64 1910 case 0b10'011: // c.ldsp (rd != x0) 1911 #endif 1912 return rd ? SignalContext::READ : SignalContext::UNKNOWN; 1913 case 0b00'010: // c.lw 1914 #if __riscv_flen >= 32 && __riscv_xlen == 32 1915 case 0b10'011: // c.flwsp 1916 #endif 1917 #if __riscv_flen >= 32 || __riscv_xlen == 64 1918 case 0b00'011: // c.flw / c.ld 1919 #endif 1920 #if __riscv_flen == 64 1921 case 0b00'001: // c.fld 1922 case 0b10'001: // c.fldsp 1923 #endif 1924 return SignalContext::READ; 1925 case 0b00'110: // c.sw 1926 case 0b10'110: // c.swsp 1927 #if __riscv_flen >= 32 || __riscv_xlen == 64 1928 case 0b00'111: // c.fsw / c.sd 1929 case 0b10'111: // c.fswsp / c.sdsp 1930 #endif 1931 #if __riscv_flen == 64 1932 case 0b00'101: // c.fsd 1933 case 0b10'101: // c.fsdsp 1934 #endif 1935 return SignalContext::WRITE; 1936 default: 1937 return SignalContext::UNKNOWN; 1938 } 1939 } 1940 #endif 1941 1942 unsigned opcode = faulty_instruction & 0x7f; // lower 7 bits 1943 unsigned funct3 = (faulty_instruction >> 12) & 0x7; // bits 12-14, inclusive 1944 switch (opcode) { 1945 case 0b0000011: // loads 1946 switch (funct3) { 1947 case 0b000: // lb 1948 case 0b001: // lh 1949 case 0b010: // lw 1950 #if __riscv_xlen == 64 1951 case 0b011: // ld 1952 #endif 1953 case 0b100: // lbu 1954 case 0b101: // lhu 1955 return SignalContext::READ; 1956 default: 1957 return SignalContext::UNKNOWN; 1958 } 1959 case 0b0100011: // stores 1960 switch (funct3) { 1961 case 0b000: // sb 1962 case 0b001: // sh 1963 case 0b010: // sw 1964 #if __riscv_xlen == 64 1965 case 0b011: // sd 1966 #endif 1967 return SignalContext::WRITE; 1968 default: 1969 return SignalContext::UNKNOWN; 1970 } 1971 #if __riscv_flen >= 32 1972 case 0b0000111: // floating-point loads 1973 switch (funct3) { 1974 case 0b010: // flw 1975 #if __riscv_flen == 64 1976 case 0b011: // fld 1977 #endif 1978 return SignalContext::READ; 1979 default: 1980 return SignalContext::UNKNOWN; 1981 } 1982 case 0b0100111: // floating-point stores 1983 switch (funct3) { 1984 case 0b010: // fsw 1985 #if __riscv_flen == 64 1986 case 0b011: // fsd 1987 #endif 1988 return SignalContext::WRITE; 1989 default: 1990 return SignalContext::UNKNOWN; 1991 } 1992 #endif 1993 default: 1994 return SignalContext::UNKNOWN; 1995 } 1996 #else 1997 (void)ucontext; 1998 return UNKNOWN; // FIXME: Implement. 1999 #endif 2000 } 2001 2002 bool SignalContext::IsTrueFaultingAddress() const { 2003 auto si = static_cast<const siginfo_t *>(siginfo); 2004 // SIGSEGV signals without a true fault address have si_code set to 128. 2005 return si->si_signo == SIGSEGV && si->si_code != 128; 2006 } 2007 2008 void SignalContext::DumpAllRegisters(void *context) { 2009 // FIXME: Implement this. 2010 } 2011 2012 static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) { 2013 #if SANITIZER_NETBSD 2014 // This covers all NetBSD architectures 2015 ucontext_t *ucontext = (ucontext_t *)context; 2016 *pc = _UC_MACHINE_PC(ucontext); 2017 *bp = _UC_MACHINE_FP(ucontext); 2018 *sp = _UC_MACHINE_SP(ucontext); 2019 #elif defined(__arm__) 2020 ucontext_t *ucontext = (ucontext_t*)context; 2021 *pc = ucontext->uc_mcontext.arm_pc; 2022 *bp = ucontext->uc_mcontext.arm_fp; 2023 *sp = ucontext->uc_mcontext.arm_sp; 2024 #elif defined(__aarch64__) 2025 ucontext_t *ucontext = (ucontext_t*)context; 2026 *pc = ucontext->uc_mcontext.pc; 2027 *bp = ucontext->uc_mcontext.regs[29]; 2028 *sp = ucontext->uc_mcontext.sp; 2029 #elif defined(__hppa__) 2030 ucontext_t *ucontext = (ucontext_t*)context; 2031 *pc = ucontext->uc_mcontext.sc_iaoq[0]; 2032 /* GCC uses %r3 whenever a frame pointer is needed. */ 2033 *bp = ucontext->uc_mcontext.sc_gr[3]; 2034 *sp = ucontext->uc_mcontext.sc_gr[30]; 2035 #elif defined(__x86_64__) 2036 # if SANITIZER_FREEBSD 2037 ucontext_t *ucontext = (ucontext_t*)context; 2038 *pc = ucontext->uc_mcontext.mc_rip; 2039 *bp = ucontext->uc_mcontext.mc_rbp; 2040 *sp = ucontext->uc_mcontext.mc_rsp; 2041 # else 2042 ucontext_t *ucontext = (ucontext_t*)context; 2043 *pc = ucontext->uc_mcontext.gregs[REG_RIP]; 2044 *bp = ucontext->uc_mcontext.gregs[REG_RBP]; 2045 *sp = ucontext->uc_mcontext.gregs[REG_RSP]; 2046 # endif 2047 #elif defined(__i386__) 2048 # if SANITIZER_FREEBSD 2049 ucontext_t *ucontext = (ucontext_t*)context; 2050 *pc = ucontext->uc_mcontext.mc_eip; 2051 *bp = ucontext->uc_mcontext.mc_ebp; 2052 *sp = ucontext->uc_mcontext.mc_esp; 2053 # else 2054 ucontext_t *ucontext = (ucontext_t*)context; 2055 # if SANITIZER_SOLARIS 2056 /* Use the numeric values: the symbolic ones are undefined by llvm 2057 include/llvm/Support/Solaris.h. */ 2058 # ifndef REG_EIP 2059 # define REG_EIP 14 // REG_PC 2060 # endif 2061 # ifndef REG_EBP 2062 # define REG_EBP 6 // REG_FP 2063 # endif 2064 # ifndef REG_UESP 2065 # define REG_UESP 17 // REG_SP 2066 # endif 2067 # endif 2068 *pc = ucontext->uc_mcontext.gregs[REG_EIP]; 2069 *bp = ucontext->uc_mcontext.gregs[REG_EBP]; 2070 *sp = ucontext->uc_mcontext.gregs[REG_UESP]; 2071 # endif 2072 #elif defined(__powerpc__) || defined(__powerpc64__) 2073 ucontext_t *ucontext = (ucontext_t*)context; 2074 *pc = ucontext->uc_mcontext.regs->nip; 2075 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1]; 2076 // The powerpc{,64}-linux ABIs do not specify r31 as the frame 2077 // pointer, but GCC always uses r31 when we need a frame pointer. 2078 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31]; 2079 #elif defined(__sparc__) 2080 #if defined(__arch64__) || defined(__sparcv9) 2081 #define STACK_BIAS 2047 2082 #else 2083 #define STACK_BIAS 0 2084 # endif 2085 # if SANITIZER_SOLARIS 2086 ucontext_t *ucontext = (ucontext_t *)context; 2087 *pc = ucontext->uc_mcontext.gregs[REG_PC]; 2088 *sp = ucontext->uc_mcontext.gregs[REG_O6] + STACK_BIAS; 2089 #else 2090 // Historical BSDism here. 2091 struct sigcontext *scontext = (struct sigcontext *)context; 2092 #if defined(__arch64__) 2093 *pc = scontext->sigc_regs.tpc; 2094 *sp = scontext->sigc_regs.u_regs[14] + STACK_BIAS; 2095 #else 2096 *pc = scontext->si_regs.pc; 2097 *sp = scontext->si_regs.u_regs[14]; 2098 #endif 2099 # endif 2100 *bp = (uptr)((uhwptr *)*sp)[14] + STACK_BIAS; 2101 #elif defined(__mips__) 2102 ucontext_t *ucontext = (ucontext_t*)context; 2103 *pc = ucontext->uc_mcontext.pc; 2104 *bp = ucontext->uc_mcontext.gregs[30]; 2105 *sp = ucontext->uc_mcontext.gregs[29]; 2106 #elif defined(__s390__) 2107 ucontext_t *ucontext = (ucontext_t*)context; 2108 # if defined(__s390x__) 2109 *pc = ucontext->uc_mcontext.psw.addr; 2110 # else 2111 *pc = ucontext->uc_mcontext.psw.addr & 0x7fffffff; 2112 # endif 2113 *bp = ucontext->uc_mcontext.gregs[11]; 2114 *sp = ucontext->uc_mcontext.gregs[15]; 2115 #elif defined(__riscv) 2116 ucontext_t *ucontext = (ucontext_t*)context; 2117 # if SANITIZER_FREEBSD 2118 *pc = ucontext->uc_mcontext.mc_gpregs.gp_sepc; 2119 *bp = ucontext->uc_mcontext.mc_gpregs.gp_s[0]; 2120 *sp = ucontext->uc_mcontext.mc_gpregs.gp_sp; 2121 # else 2122 *pc = ucontext->uc_mcontext.__gregs[REG_PC]; 2123 *bp = ucontext->uc_mcontext.__gregs[REG_S0]; 2124 *sp = ucontext->uc_mcontext.__gregs[REG_SP]; 2125 # endif 2126 # elif defined(__hexagon__) 2127 ucontext_t *ucontext = (ucontext_t *)context; 2128 *pc = ucontext->uc_mcontext.pc; 2129 *bp = ucontext->uc_mcontext.r30; 2130 *sp = ucontext->uc_mcontext.r29; 2131 # else 2132 # error "Unsupported arch" 2133 # endif 2134 } 2135 2136 void SignalContext::InitPcSpBp() { GetPcSpBp(context, &pc, &sp, &bp); } 2137 2138 void InitializePlatformEarly() { 2139 // Do nothing. 2140 } 2141 2142 void MaybeReexec() { 2143 // No need to re-exec on Linux. 2144 } 2145 2146 void CheckASLR() { 2147 #if SANITIZER_NETBSD 2148 int mib[3]; 2149 int paxflags; 2150 uptr len = sizeof(paxflags); 2151 2152 mib[0] = CTL_PROC; 2153 mib[1] = internal_getpid(); 2154 mib[2] = PROC_PID_PAXFLAGS; 2155 2156 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2157 Printf("sysctl failed\n"); 2158 Die(); 2159 } 2160 2161 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_ASLR)) { 2162 Printf("This sanitizer is not compatible with enabled ASLR.\n" 2163 "To disable ASLR, please run \"paxctl +a %s\" and try again.\n", 2164 GetArgv()[0]); 2165 Die(); 2166 } 2167 #elif SANITIZER_PPC64V2 2168 // Disable ASLR for Linux PPC64LE. 2169 int old_personality = personality(0xffffffff); 2170 if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) { 2171 VReport(1, "WARNING: Program is being run with address space layout " 2172 "randomization (ASLR) enabled which prevents the thread and " 2173 "memory sanitizers from working on powerpc64le.\n" 2174 "ASLR will be disabled and the program re-executed.\n"); 2175 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1); 2176 ReExec(); 2177 } 2178 #elif SANITIZER_FREEBSD 2179 int aslr_pie; 2180 uptr len = sizeof(aslr_pie); 2181 #if SANITIZER_WORDSIZE == 64 2182 if (UNLIKELY(internal_sysctlbyname("kern.elf64.aslr.pie_enable", 2183 &aslr_pie, &len, NULL, 0) == -1)) { 2184 // We're making things less 'dramatic' here since 2185 // the OID is not necessarily guaranteed to be here 2186 // just yet regarding FreeBSD release 2187 return; 2188 } 2189 2190 if (aslr_pie > 0) { 2191 Printf("This sanitizer is not compatible with enabled ASLR " 2192 "and binaries compiled with PIE\n"); 2193 Die(); 2194 } 2195 #endif 2196 // there might be 32 bits compat for 64 bits 2197 if (UNLIKELY(internal_sysctlbyname("kern.elf32.aslr.pie_enable", 2198 &aslr_pie, &len, NULL, 0) == -1)) { 2199 return; 2200 } 2201 2202 if (aslr_pie > 0) { 2203 Printf("This sanitizer is not compatible with enabled ASLR " 2204 "and binaries compiled with PIE\n"); 2205 Die(); 2206 } 2207 #else 2208 // Do nothing 2209 #endif 2210 } 2211 2212 void CheckMPROTECT() { 2213 #if SANITIZER_NETBSD 2214 int mib[3]; 2215 int paxflags; 2216 uptr len = sizeof(paxflags); 2217 2218 mib[0] = CTL_PROC; 2219 mib[1] = internal_getpid(); 2220 mib[2] = PROC_PID_PAXFLAGS; 2221 2222 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2223 Printf("sysctl failed\n"); 2224 Die(); 2225 } 2226 2227 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_MPROTECT)) { 2228 Printf("This sanitizer is not compatible with enabled MPROTECT\n"); 2229 Die(); 2230 } 2231 #else 2232 // Do nothing 2233 #endif 2234 } 2235 2236 void CheckNoDeepBind(const char *filename, int flag) { 2237 #ifdef RTLD_DEEPBIND 2238 if (flag & RTLD_DEEPBIND) { 2239 Report( 2240 "You are trying to dlopen a %s shared library with RTLD_DEEPBIND flag" 2241 " which is incompatible with sanitizer runtime " 2242 "(see https://github.com/google/sanitizers/issues/611 for details" 2243 "). If you want to run %s library under sanitizers please remove " 2244 "RTLD_DEEPBIND from dlopen flags.\n", 2245 filename, filename); 2246 Die(); 2247 } 2248 #endif 2249 } 2250 2251 uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding, 2252 uptr *largest_gap_found, 2253 uptr *max_occupied_addr) { 2254 UNREACHABLE("FindAvailableMemoryRange is not available"); 2255 return 0; 2256 } 2257 2258 bool GetRandom(void *buffer, uptr length, bool blocking) { 2259 if (!buffer || !length || length > 256) 2260 return false; 2261 #if SANITIZER_USE_GETENTROPY 2262 uptr rnd = getentropy(buffer, length); 2263 int rverrno = 0; 2264 if (internal_iserror(rnd, &rverrno) && rverrno == EFAULT) 2265 return false; 2266 else if (rnd == 0) 2267 return true; 2268 #endif // SANITIZER_USE_GETENTROPY 2269 2270 #if SANITIZER_USE_GETRANDOM 2271 static atomic_uint8_t skip_getrandom_syscall; 2272 if (!atomic_load_relaxed(&skip_getrandom_syscall)) { 2273 // Up to 256 bytes, getrandom will not be interrupted. 2274 uptr res = internal_syscall(SYSCALL(getrandom), buffer, length, 2275 blocking ? 0 : GRND_NONBLOCK); 2276 int rverrno = 0; 2277 if (internal_iserror(res, &rverrno) && rverrno == ENOSYS) 2278 atomic_store_relaxed(&skip_getrandom_syscall, 1); 2279 else if (res == length) 2280 return true; 2281 } 2282 #endif // SANITIZER_USE_GETRANDOM 2283 // Up to 256 bytes, a read off /dev/urandom will not be interrupted. 2284 // blocking is moot here, O_NONBLOCK has no effect when opening /dev/urandom. 2285 uptr fd = internal_open("/dev/urandom", O_RDONLY); 2286 if (internal_iserror(fd)) 2287 return false; 2288 uptr res = internal_read(fd, buffer, length); 2289 if (internal_iserror(res)) 2290 return false; 2291 internal_close(fd); 2292 return true; 2293 } 2294 2295 } // namespace __sanitizer 2296 2297 #endif 2298