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/procctl.h> 84 #include <sys/sysctl.h> 85 #include <machine/atomic.h> 86 extern "C" { 87 // <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on 88 // FreeBSD 9.2 and 10.0. 89 #include <sys/umtx.h> 90 } 91 #include <sys/thr.h> 92 #endif // SANITIZER_FREEBSD 93 94 #if SANITIZER_NETBSD 95 #include <limits.h> // For NAME_MAX 96 #include <sys/sysctl.h> 97 #include <sys/exec.h> 98 extern struct ps_strings *__ps_strings; 99 #endif // SANITIZER_NETBSD 100 101 #if SANITIZER_SOLARIS 102 #include <stdlib.h> 103 #include <thread.h> 104 #define environ _environ 105 #endif 106 107 extern char **environ; 108 109 #if SANITIZER_LINUX 110 // <linux/time.h> 111 struct kernel_timeval { 112 long tv_sec; 113 long tv_usec; 114 }; 115 116 // <linux/futex.h> is broken on some linux distributions. 117 const int FUTEX_WAIT = 0; 118 const int FUTEX_WAKE = 1; 119 const int FUTEX_PRIVATE_FLAG = 128; 120 const int FUTEX_WAIT_PRIVATE = FUTEX_WAIT | FUTEX_PRIVATE_FLAG; 121 const int FUTEX_WAKE_PRIVATE = FUTEX_WAKE | FUTEX_PRIVATE_FLAG; 122 #endif // SANITIZER_LINUX 123 124 // Are we using 32-bit or 64-bit Linux syscalls? 125 // x32 (which defines __x86_64__) has SANITIZER_WORDSIZE == 32 126 // but it still needs to use 64-bit syscalls. 127 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__powerpc64__) || \ 128 SANITIZER_WORDSIZE == 64) 129 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 1 130 #else 131 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 0 132 #endif 133 134 // Note : FreeBSD had implemented both 135 // Linux apis, available from 136 // future 12.x version most likely 137 #if SANITIZER_LINUX && defined(__NR_getrandom) 138 # if !defined(GRND_NONBLOCK) 139 # define GRND_NONBLOCK 1 140 # endif 141 # define SANITIZER_USE_GETRANDOM 1 142 #else 143 # define SANITIZER_USE_GETRANDOM 0 144 #endif // SANITIZER_LINUX && defined(__NR_getrandom) 145 146 #if SANITIZER_FREEBSD && __FreeBSD_version >= 1200000 147 # define SANITIZER_USE_GETENTROPY 1 148 #else 149 # define SANITIZER_USE_GETENTROPY 0 150 #endif 151 152 namespace __sanitizer { 153 154 void SetSigProcMask(__sanitizer_sigset_t *set, __sanitizer_sigset_t *old) { 155 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, set, old)); 156 } 157 158 ScopedBlockSignals::ScopedBlockSignals(__sanitizer_sigset_t *copy) { 159 __sanitizer_sigset_t set; 160 internal_sigfillset(&set); 161 # if SANITIZER_LINUX && !SANITIZER_ANDROID 162 // Glibc uses SIGSETXID signal during setuid call. If this signal is blocked 163 // on any thread, setuid call hangs. 164 // See test/sanitizer_common/TestCases/Linux/setuid.c. 165 internal_sigdelset(&set, 33); 166 # endif 167 # if SANITIZER_LINUX 168 // Seccomp-BPF-sandboxed processes rely on SIGSYS to handle trapped syscalls. 169 // If this signal is blocked, such calls cannot be handled and the process may 170 // hang. 171 internal_sigdelset(&set, 31); 172 # endif 173 SetSigProcMask(&set, &saved_); 174 if (copy) 175 internal_memcpy(copy, &saved_, sizeof(saved_)); 176 } 177 178 ScopedBlockSignals::~ScopedBlockSignals() { SetSigProcMask(&saved_, nullptr); } 179 180 # if SANITIZER_LINUX && defined(__x86_64__) 181 # include "sanitizer_syscall_linux_x86_64.inc" 182 # elif SANITIZER_LINUX && SANITIZER_RISCV64 183 # include "sanitizer_syscall_linux_riscv64.inc" 184 # elif SANITIZER_LINUX && defined(__aarch64__) 185 # include "sanitizer_syscall_linux_aarch64.inc" 186 # elif SANITIZER_LINUX && defined(__arm__) 187 # include "sanitizer_syscall_linux_arm.inc" 188 # elif SANITIZER_LINUX && defined(__hexagon__) 189 # include "sanitizer_syscall_linux_hexagon.inc" 190 # else 191 # include "sanitizer_syscall_generic.inc" 192 # endif 193 194 // --------------- sanitizer_libc.h 195 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 196 #if !SANITIZER_S390 197 uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd, 198 u64 offset) { 199 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 200 return internal_syscall(SYSCALL(mmap), (uptr)addr, length, prot, flags, fd, 201 offset); 202 #else 203 // mmap2 specifies file offset in 4096-byte units. 204 CHECK(IsAligned(offset, 4096)); 205 return internal_syscall(SYSCALL(mmap2), addr, length, prot, flags, fd, 206 offset / 4096); 207 #endif 208 } 209 #endif // !SANITIZER_S390 210 211 uptr internal_munmap(void *addr, uptr length) { 212 return internal_syscall(SYSCALL(munmap), (uptr)addr, length); 213 } 214 215 #if SANITIZER_LINUX 216 uptr internal_mremap(void *old_address, uptr old_size, uptr new_size, int flags, 217 void *new_address) { 218 return internal_syscall(SYSCALL(mremap), (uptr)old_address, old_size, 219 new_size, flags, (uptr)new_address); 220 } 221 #endif 222 223 int internal_mprotect(void *addr, uptr length, int prot) { 224 return internal_syscall(SYSCALL(mprotect), (uptr)addr, length, prot); 225 } 226 227 int internal_madvise(uptr addr, uptr length, int advice) { 228 return internal_syscall(SYSCALL(madvise), addr, length, advice); 229 } 230 231 uptr internal_close(fd_t fd) { 232 return internal_syscall(SYSCALL(close), fd); 233 } 234 235 uptr internal_open(const char *filename, int flags) { 236 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 237 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags); 238 #else 239 return internal_syscall(SYSCALL(open), (uptr)filename, flags); 240 #endif 241 } 242 243 uptr internal_open(const char *filename, int flags, u32 mode) { 244 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 245 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags, 246 mode); 247 #else 248 return internal_syscall(SYSCALL(open), (uptr)filename, flags, mode); 249 #endif 250 } 251 252 uptr internal_read(fd_t fd, void *buf, uptr count) { 253 sptr res; 254 HANDLE_EINTR(res, 255 (sptr)internal_syscall(SYSCALL(read), fd, (uptr)buf, count)); 256 return res; 257 } 258 259 uptr internal_write(fd_t fd, const void *buf, uptr count) { 260 sptr res; 261 HANDLE_EINTR(res, 262 (sptr)internal_syscall(SYSCALL(write), fd, (uptr)buf, count)); 263 return res; 264 } 265 266 uptr internal_ftruncate(fd_t fd, uptr size) { 267 sptr res; 268 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(ftruncate), fd, 269 (OFF_T)size)); 270 return res; 271 } 272 273 #if !SANITIZER_LINUX_USES_64BIT_SYSCALLS && SANITIZER_LINUX 274 static void stat64_to_stat(struct stat64 *in, struct stat *out) { 275 internal_memset(out, 0, sizeof(*out)); 276 out->st_dev = in->st_dev; 277 out->st_ino = in->st_ino; 278 out->st_mode = in->st_mode; 279 out->st_nlink = in->st_nlink; 280 out->st_uid = in->st_uid; 281 out->st_gid = in->st_gid; 282 out->st_rdev = in->st_rdev; 283 out->st_size = in->st_size; 284 out->st_blksize = in->st_blksize; 285 out->st_blocks = in->st_blocks; 286 out->st_atime = in->st_atime; 287 out->st_mtime = in->st_mtime; 288 out->st_ctime = in->st_ctime; 289 } 290 #endif 291 292 #if defined(__mips64) 293 // Undefine compatibility macros from <sys/stat.h> 294 // so that they would not clash with the kernel_stat 295 // st_[a|m|c]time fields 296 #if !SANITIZER_GO 297 #undef st_atime 298 #undef st_mtime 299 #undef st_ctime 300 #endif 301 #if defined(SANITIZER_ANDROID) 302 // Bionic sys/stat.h defines additional macros 303 // for compatibility with the old NDKs and 304 // they clash with the kernel_stat structure 305 // st_[a|m|c]time_nsec fields. 306 #undef st_atime_nsec 307 #undef st_mtime_nsec 308 #undef st_ctime_nsec 309 #endif 310 static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) { 311 internal_memset(out, 0, sizeof(*out)); 312 out->st_dev = in->st_dev; 313 out->st_ino = in->st_ino; 314 out->st_mode = in->st_mode; 315 out->st_nlink = in->st_nlink; 316 out->st_uid = in->st_uid; 317 out->st_gid = in->st_gid; 318 out->st_rdev = in->st_rdev; 319 out->st_size = in->st_size; 320 out->st_blksize = in->st_blksize; 321 out->st_blocks = in->st_blocks; 322 #if defined(__USE_MISC) || \ 323 defined(__USE_XOPEN2K8) || \ 324 defined(SANITIZER_ANDROID) 325 out->st_atim.tv_sec = in->st_atime; 326 out->st_atim.tv_nsec = in->st_atime_nsec; 327 out->st_mtim.tv_sec = in->st_mtime; 328 out->st_mtim.tv_nsec = in->st_mtime_nsec; 329 out->st_ctim.tv_sec = in->st_ctime; 330 out->st_ctim.tv_nsec = in->st_ctime_nsec; 331 #else 332 out->st_atime = in->st_atime; 333 out->st_atimensec = in->st_atime_nsec; 334 out->st_mtime = in->st_mtime; 335 out->st_mtimensec = in->st_mtime_nsec; 336 out->st_ctime = in->st_ctime; 337 out->st_atimensec = in->st_ctime_nsec; 338 #endif 339 } 340 #endif 341 342 uptr internal_stat(const char *path, void *buf) { 343 #if SANITIZER_FREEBSD 344 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 0); 345 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 346 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 347 0); 348 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 349 # if defined(__mips64) 350 // For mips64, stat syscall fills buffer in the format of kernel_stat 351 struct kernel_stat kbuf; 352 int res = internal_syscall(SYSCALL(stat), path, &kbuf); 353 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 354 return res; 355 # else 356 return internal_syscall(SYSCALL(stat), (uptr)path, (uptr)buf); 357 # endif 358 #else 359 struct stat64 buf64; 360 int res = internal_syscall(SYSCALL(stat64), path, &buf64); 361 stat64_to_stat(&buf64, (struct stat *)buf); 362 return res; 363 #endif 364 } 365 366 uptr internal_lstat(const char *path, void *buf) { 367 #if SANITIZER_FREEBSD 368 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 369 AT_SYMLINK_NOFOLLOW); 370 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 371 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 372 AT_SYMLINK_NOFOLLOW); 373 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 374 # if SANITIZER_MIPS64 375 // For mips64, lstat syscall fills buffer in the format of kernel_stat 376 struct kernel_stat kbuf; 377 int res = internal_syscall(SYSCALL(lstat), path, &kbuf); 378 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 379 return res; 380 # else 381 return internal_syscall(SYSCALL(lstat), (uptr)path, (uptr)buf); 382 # endif 383 #else 384 struct stat64 buf64; 385 int res = internal_syscall(SYSCALL(lstat64), path, &buf64); 386 stat64_to_stat(&buf64, (struct stat *)buf); 387 return res; 388 #endif 389 } 390 391 uptr internal_fstat(fd_t fd, void *buf) { 392 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 393 #if SANITIZER_MIPS64 394 // For mips64, fstat syscall fills buffer in the format of kernel_stat 395 struct kernel_stat kbuf; 396 int res = internal_syscall(SYSCALL(fstat), fd, &kbuf); 397 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 398 return res; 399 # else 400 return internal_syscall(SYSCALL(fstat), fd, (uptr)buf); 401 # endif 402 #else 403 struct stat64 buf64; 404 int res = internal_syscall(SYSCALL(fstat64), fd, &buf64); 405 stat64_to_stat(&buf64, (struct stat *)buf); 406 return res; 407 #endif 408 } 409 410 uptr internal_filesize(fd_t fd) { 411 struct stat st; 412 if (internal_fstat(fd, &st)) 413 return -1; 414 return (uptr)st.st_size; 415 } 416 417 uptr internal_dup(int oldfd) { 418 return internal_syscall(SYSCALL(dup), oldfd); 419 } 420 421 uptr internal_dup2(int oldfd, int newfd) { 422 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 423 return internal_syscall(SYSCALL(dup3), oldfd, newfd, 0); 424 #else 425 return internal_syscall(SYSCALL(dup2), oldfd, newfd); 426 #endif 427 } 428 429 uptr internal_readlink(const char *path, char *buf, uptr bufsize) { 430 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 431 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD, (uptr)path, (uptr)buf, 432 bufsize); 433 #else 434 return internal_syscall(SYSCALL(readlink), (uptr)path, (uptr)buf, bufsize); 435 #endif 436 } 437 438 uptr internal_unlink(const char *path) { 439 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 440 return internal_syscall(SYSCALL(unlinkat), AT_FDCWD, (uptr)path, 0); 441 #else 442 return internal_syscall(SYSCALL(unlink), (uptr)path); 443 #endif 444 } 445 446 uptr internal_rename(const char *oldpath, const char *newpath) { 447 #if defined(__riscv) && defined(__linux__) 448 return internal_syscall(SYSCALL(renameat2), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 449 (uptr)newpath, 0); 450 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 451 return internal_syscall(SYSCALL(renameat), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 452 (uptr)newpath); 453 #else 454 return internal_syscall(SYSCALL(rename), (uptr)oldpath, (uptr)newpath); 455 #endif 456 } 457 458 uptr internal_sched_yield() { 459 return internal_syscall(SYSCALL(sched_yield)); 460 } 461 462 void internal_usleep(u64 useconds) { 463 struct timespec ts; 464 ts.tv_sec = useconds / 1000000; 465 ts.tv_nsec = (useconds % 1000000) * 1000; 466 internal_syscall(SYSCALL(nanosleep), &ts, &ts); 467 } 468 469 uptr internal_execve(const char *filename, char *const argv[], 470 char *const envp[]) { 471 return internal_syscall(SYSCALL(execve), (uptr)filename, (uptr)argv, 472 (uptr)envp); 473 } 474 #endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD 475 476 #if !SANITIZER_NETBSD 477 void internal__exit(int exitcode) { 478 #if SANITIZER_FREEBSD || SANITIZER_SOLARIS 479 internal_syscall(SYSCALL(exit), exitcode); 480 #else 481 internal_syscall(SYSCALL(exit_group), exitcode); 482 #endif 483 Die(); // Unreachable. 484 } 485 #endif // !SANITIZER_NETBSD 486 487 // ----------------- sanitizer_common.h 488 bool FileExists(const char *filename) { 489 if (ShouldMockFailureToOpen(filename)) 490 return false; 491 struct stat st; 492 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 493 if (internal_syscall(SYSCALL(newfstatat), AT_FDCWD, filename, &st, 0)) 494 #else 495 if (internal_stat(filename, &st)) 496 #endif 497 return false; 498 // Sanity check: filename is a regular file. 499 return S_ISREG(st.st_mode); 500 } 501 502 bool DirExists(const char *path) { 503 struct stat st; 504 # if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 505 if (internal_syscall(SYSCALL(newfstatat), AT_FDCWD, path, &st, 0)) 506 # else 507 if (internal_stat(path, &st)) 508 # endif 509 return false; 510 return S_ISDIR(st.st_mode); 511 } 512 513 # if !SANITIZER_NETBSD 514 tid_t GetTid() { 515 #if SANITIZER_FREEBSD 516 long Tid; 517 thr_self(&Tid); 518 return Tid; 519 #elif SANITIZER_SOLARIS 520 return thr_self(); 521 #else 522 return internal_syscall(SYSCALL(gettid)); 523 #endif 524 } 525 526 int TgKill(pid_t pid, tid_t tid, int sig) { 527 #if SANITIZER_LINUX 528 return internal_syscall(SYSCALL(tgkill), pid, tid, sig); 529 #elif SANITIZER_FREEBSD 530 return internal_syscall(SYSCALL(thr_kill2), pid, tid, sig); 531 #elif SANITIZER_SOLARIS 532 (void)pid; 533 return thr_kill(tid, sig); 534 #endif 535 } 536 #endif 537 538 #if SANITIZER_GLIBC 539 u64 NanoTime() { 540 kernel_timeval tv; 541 internal_memset(&tv, 0, sizeof(tv)); 542 internal_syscall(SYSCALL(gettimeofday), &tv, 0); 543 return (u64)tv.tv_sec * 1000 * 1000 * 1000 + tv.tv_usec * 1000; 544 } 545 // Used by real_clock_gettime. 546 uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) { 547 return internal_syscall(SYSCALL(clock_gettime), clk_id, tp); 548 } 549 #elif !SANITIZER_SOLARIS && !SANITIZER_NETBSD 550 u64 NanoTime() { 551 struct timespec ts; 552 clock_gettime(CLOCK_REALTIME, &ts); 553 return (u64)ts.tv_sec * 1000 * 1000 * 1000 + ts.tv_nsec; 554 } 555 #endif 556 557 // Like getenv, but reads env directly from /proc (on Linux) or parses the 558 // 'environ' array (on some others) and does not use libc. This function 559 // should be called first inside __asan_init. 560 const char *GetEnv(const char *name) { 561 #if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_SOLARIS 562 if (::environ != 0) { 563 uptr NameLen = internal_strlen(name); 564 for (char **Env = ::environ; *Env != 0; Env++) { 565 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=') 566 return (*Env) + NameLen + 1; 567 } 568 } 569 return 0; // Not found. 570 #elif SANITIZER_LINUX 571 static char *environ; 572 static uptr len; 573 static bool inited; 574 if (!inited) { 575 inited = true; 576 uptr environ_size; 577 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len)) 578 environ = nullptr; 579 } 580 if (!environ || len == 0) return nullptr; 581 uptr namelen = internal_strlen(name); 582 const char *p = environ; 583 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer 584 // proc file has the format NAME=value\0NAME=value\0NAME=value\0... 585 const char* endp = 586 (char*)internal_memchr(p, '\0', len - (p - environ)); 587 if (!endp) // this entry isn't NUL terminated 588 return nullptr; 589 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match. 590 return p + namelen + 1; // point after = 591 p = endp + 1; 592 } 593 return nullptr; // Not found. 594 #else 595 #error "Unsupported platform" 596 #endif 597 } 598 599 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD && !SANITIZER_GO 600 extern "C" { 601 SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end; 602 } 603 #endif 604 605 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD 606 static void ReadNullSepFileToArray(const char *path, char ***arr, 607 int arr_size) { 608 char *buff; 609 uptr buff_size; 610 uptr buff_len; 611 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray"); 612 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) { 613 (*arr)[0] = nullptr; 614 return; 615 } 616 (*arr)[0] = buff; 617 int count, i; 618 for (count = 1, i = 1; ; i++) { 619 if (buff[i] == 0) { 620 if (buff[i+1] == 0) break; 621 (*arr)[count] = &buff[i+1]; 622 CHECK_LE(count, arr_size - 1); // FIXME: make this more flexible. 623 count++; 624 } 625 } 626 (*arr)[count] = nullptr; 627 } 628 #endif 629 630 static void GetArgsAndEnv(char ***argv, char ***envp) { 631 #if SANITIZER_FREEBSD 632 // On FreeBSD, retrieving the argument and environment arrays is done via the 633 // kern.ps_strings sysctl, which returns a pointer to a structure containing 634 // this information. See also <sys/exec.h>. 635 ps_strings *pss; 636 uptr sz = sizeof(pss); 637 if (internal_sysctlbyname("kern.ps_strings", &pss, &sz, NULL, 0) == -1) { 638 Printf("sysctl kern.ps_strings failed\n"); 639 Die(); 640 } 641 *argv = pss->ps_argvstr; 642 *envp = pss->ps_envstr; 643 #elif SANITIZER_NETBSD 644 *argv = __ps_strings->ps_argvstr; 645 *envp = __ps_strings->ps_envstr; 646 #else // SANITIZER_FREEBSD 647 #if !SANITIZER_GO 648 if (&__libc_stack_end) { 649 uptr* stack_end = (uptr*)__libc_stack_end; 650 // Normally argc can be obtained from *stack_end, however, on ARM glibc's 651 // _start clobbers it: 652 // https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/arm/start.S;hb=refs/heads/release/2.31/master#l75 653 // Do not special-case ARM and infer argc from argv everywhere. 654 int argc = 0; 655 while (stack_end[argc + 1]) argc++; 656 *argv = (char**)(stack_end + 1); 657 *envp = (char**)(stack_end + argc + 2); 658 } else { 659 #endif // !SANITIZER_GO 660 static const int kMaxArgv = 2000, kMaxEnvp = 2000; 661 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv); 662 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp); 663 #if !SANITIZER_GO 664 } 665 #endif // !SANITIZER_GO 666 #endif // SANITIZER_FREEBSD 667 } 668 669 char **GetArgv() { 670 char **argv, **envp; 671 GetArgsAndEnv(&argv, &envp); 672 return argv; 673 } 674 675 char **GetEnviron() { 676 char **argv, **envp; 677 GetArgsAndEnv(&argv, &envp); 678 return envp; 679 } 680 681 #if !SANITIZER_SOLARIS 682 void FutexWait(atomic_uint32_t *p, u32 cmp) { 683 # if SANITIZER_FREEBSD 684 _umtx_op(p, UMTX_OP_WAIT_UINT, cmp, 0, 0); 685 # elif SANITIZER_NETBSD 686 sched_yield(); /* No userspace futex-like synchronization */ 687 # else 688 internal_syscall(SYSCALL(futex), (uptr)p, FUTEX_WAIT_PRIVATE, cmp, 0, 0, 0); 689 # endif 690 } 691 692 void FutexWake(atomic_uint32_t *p, u32 count) { 693 # if SANITIZER_FREEBSD 694 _umtx_op(p, UMTX_OP_WAKE, count, 0, 0); 695 # elif SANITIZER_NETBSD 696 /* No userspace futex-like synchronization */ 697 # else 698 internal_syscall(SYSCALL(futex), (uptr)p, FUTEX_WAKE_PRIVATE, count, 0, 0, 0); 699 # endif 700 } 701 702 # endif // !SANITIZER_SOLARIS 703 704 // ----------------- sanitizer_linux.h 705 // The actual size of this structure is specified by d_reclen. 706 // Note that getdents64 uses a different structure format. We only provide the 707 // 32-bit syscall here. 708 #if SANITIZER_NETBSD 709 // Not used 710 #else 711 struct linux_dirent { 712 #if SANITIZER_X32 || defined(__aarch64__) || SANITIZER_RISCV64 713 u64 d_ino; 714 u64 d_off; 715 #else 716 unsigned long d_ino; 717 unsigned long d_off; 718 #endif 719 unsigned short d_reclen; 720 #if defined(__aarch64__) || SANITIZER_RISCV64 721 unsigned char d_type; 722 #endif 723 char d_name[256]; 724 }; 725 #endif 726 727 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 728 // Syscall wrappers. 729 uptr internal_ptrace(int request, int pid, void *addr, void *data) { 730 return internal_syscall(SYSCALL(ptrace), request, pid, (uptr)addr, 731 (uptr)data); 732 } 733 734 uptr internal_waitpid(int pid, int *status, int options) { 735 return internal_syscall(SYSCALL(wait4), pid, (uptr)status, options, 736 0 /* rusage */); 737 } 738 739 uptr internal_getpid() { 740 return internal_syscall(SYSCALL(getpid)); 741 } 742 743 uptr internal_getppid() { 744 return internal_syscall(SYSCALL(getppid)); 745 } 746 747 int internal_dlinfo(void *handle, int request, void *p) { 748 #if SANITIZER_FREEBSD 749 return dlinfo(handle, request, p); 750 #else 751 UNIMPLEMENTED(); 752 #endif 753 } 754 755 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) { 756 #if SANITIZER_FREEBSD 757 return internal_syscall(SYSCALL(getdirentries), fd, (uptr)dirp, count, NULL); 758 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 759 return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count); 760 #else 761 return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count); 762 #endif 763 } 764 765 uptr internal_lseek(fd_t fd, OFF_T offset, int whence) { 766 return internal_syscall(SYSCALL(lseek), fd, offset, whence); 767 } 768 769 #if SANITIZER_LINUX 770 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) { 771 return internal_syscall(SYSCALL(prctl), option, arg2, arg3, arg4, arg5); 772 } 773 #endif 774 775 uptr internal_sigaltstack(const void *ss, void *oss) { 776 return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss); 777 } 778 779 int internal_fork() { 780 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 781 return internal_syscall(SYSCALL(clone), SIGCHLD, 0); 782 #else 783 return internal_syscall(SYSCALL(fork)); 784 #endif 785 } 786 787 #if SANITIZER_FREEBSD 788 int internal_sysctl(const int *name, unsigned int namelen, void *oldp, 789 uptr *oldlenp, const void *newp, uptr newlen) { 790 return internal_syscall(SYSCALL(__sysctl), name, namelen, oldp, 791 (size_t *)oldlenp, newp, (size_t)newlen); 792 } 793 794 int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp, 795 const void *newp, uptr newlen) { 796 // Note: this function can be called during startup, so we need to avoid 797 // calling any interceptable functions. On FreeBSD >= 1300045 sysctlbyname() 798 // is a real syscall, but for older versions it calls sysctlnametomib() 799 // followed by sysctl(). To avoid calling the intercepted version and 800 // asserting if this happens during startup, call the real sysctlnametomib() 801 // followed by internal_sysctl() if the syscall is not available. 802 #ifdef SYS___sysctlbyname 803 return internal_syscall(SYSCALL(__sysctlbyname), sname, 804 internal_strlen(sname), oldp, (size_t *)oldlenp, newp, 805 (size_t)newlen); 806 #else 807 static decltype(sysctlnametomib) *real_sysctlnametomib = nullptr; 808 if (!real_sysctlnametomib) 809 real_sysctlnametomib = 810 (decltype(sysctlnametomib) *)dlsym(RTLD_NEXT, "sysctlnametomib"); 811 CHECK(real_sysctlnametomib); 812 813 int oid[CTL_MAXNAME]; 814 size_t len = CTL_MAXNAME; 815 if (real_sysctlnametomib(sname, oid, &len) == -1) 816 return (-1); 817 return internal_sysctl(oid, len, oldp, oldlenp, newp, newlen); 818 #endif 819 } 820 #endif 821 822 #if SANITIZER_LINUX 823 #define SA_RESTORER 0x04000000 824 // Doesn't set sa_restorer if the caller did not set it, so use with caution 825 //(see below). 826 int internal_sigaction_norestorer(int signum, const void *act, void *oldact) { 827 __sanitizer_kernel_sigaction_t k_act, k_oldact; 828 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t)); 829 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t)); 830 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act; 831 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact; 832 if (u_act) { 833 k_act.handler = u_act->handler; 834 k_act.sigaction = u_act->sigaction; 835 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask, 836 sizeof(__sanitizer_kernel_sigset_t)); 837 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL). 838 k_act.sa_flags = u_act->sa_flags | SA_RESTORER; 839 // FIXME: most often sa_restorer is unset, however the kernel requires it 840 // to point to a valid signal restorer that calls the rt_sigreturn syscall. 841 // If sa_restorer passed to the kernel is NULL, the program may crash upon 842 // signal delivery or fail to unwind the stack in the signal handler. 843 // libc implementation of sigaction() passes its own restorer to 844 // rt_sigaction, so we need to do the same (we'll need to reimplement the 845 // restorers; for x86_64 the restorer address can be obtained from 846 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact). 847 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 848 k_act.sa_restorer = u_act->sa_restorer; 849 #endif 850 } 851 852 uptr result = internal_syscall(SYSCALL(rt_sigaction), (uptr)signum, 853 (uptr)(u_act ? &k_act : nullptr), 854 (uptr)(u_oldact ? &k_oldact : nullptr), 855 (uptr)sizeof(__sanitizer_kernel_sigset_t)); 856 857 if ((result == 0) && u_oldact) { 858 u_oldact->handler = k_oldact.handler; 859 u_oldact->sigaction = k_oldact.sigaction; 860 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask, 861 sizeof(__sanitizer_kernel_sigset_t)); 862 u_oldact->sa_flags = k_oldact.sa_flags; 863 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 864 u_oldact->sa_restorer = k_oldact.sa_restorer; 865 #endif 866 } 867 return result; 868 } 869 #endif // SANITIZER_LINUX 870 871 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set, 872 __sanitizer_sigset_t *oldset) { 873 #if SANITIZER_FREEBSD 874 return internal_syscall(SYSCALL(sigprocmask), how, set, oldset); 875 #else 876 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 877 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset; 878 return internal_syscall(SYSCALL(rt_sigprocmask), (uptr)how, (uptr)k_set, 879 (uptr)k_oldset, sizeof(__sanitizer_kernel_sigset_t)); 880 #endif 881 } 882 883 void internal_sigfillset(__sanitizer_sigset_t *set) { 884 internal_memset(set, 0xff, sizeof(*set)); 885 } 886 887 void internal_sigemptyset(__sanitizer_sigset_t *set) { 888 internal_memset(set, 0, sizeof(*set)); 889 } 890 891 #if SANITIZER_LINUX 892 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 893 signum -= 1; 894 CHECK_GE(signum, 0); 895 CHECK_LT(signum, sizeof(*set) * 8); 896 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 897 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 898 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 899 k_set->sig[idx] &= ~((uptr)1 << bit); 900 } 901 902 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 903 signum -= 1; 904 CHECK_GE(signum, 0); 905 CHECK_LT(signum, sizeof(*set) * 8); 906 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 907 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 908 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 909 return k_set->sig[idx] & ((uptr)1 << bit); 910 } 911 #elif SANITIZER_FREEBSD 912 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 913 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 914 sigdelset(rset, signum); 915 } 916 917 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 918 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 919 return sigismember(rset, signum); 920 } 921 #endif 922 #endif // !SANITIZER_SOLARIS 923 924 #if !SANITIZER_NETBSD 925 // ThreadLister implementation. 926 ThreadLister::ThreadLister(pid_t pid) : pid_(pid), buffer_(4096) { 927 char task_directory_path[80]; 928 internal_snprintf(task_directory_path, sizeof(task_directory_path), 929 "/proc/%d/task/", pid); 930 descriptor_ = internal_open(task_directory_path, O_RDONLY | O_DIRECTORY); 931 if (internal_iserror(descriptor_)) { 932 Report("Can't open /proc/%d/task for reading.\n", pid); 933 } 934 } 935 936 ThreadLister::Result ThreadLister::ListThreads( 937 InternalMmapVector<tid_t> *threads) { 938 if (internal_iserror(descriptor_)) 939 return Error; 940 internal_lseek(descriptor_, 0, SEEK_SET); 941 threads->clear(); 942 943 Result result = Ok; 944 for (bool first_read = true;; first_read = false) { 945 // Resize to max capacity if it was downsized by IsAlive. 946 buffer_.resize(buffer_.capacity()); 947 CHECK_GE(buffer_.size(), 4096); 948 uptr read = internal_getdents( 949 descriptor_, (struct linux_dirent *)buffer_.data(), buffer_.size()); 950 if (!read) 951 return result; 952 if (internal_iserror(read)) { 953 Report("Can't read directory entries from /proc/%d/task.\n", pid_); 954 return Error; 955 } 956 957 for (uptr begin = (uptr)buffer_.data(), end = begin + read; begin < end;) { 958 struct linux_dirent *entry = (struct linux_dirent *)begin; 959 begin += entry->d_reclen; 960 if (entry->d_ino == 1) { 961 // Inode 1 is for bad blocks and also can be a reason for early return. 962 // Should be emitted if kernel tried to output terminating thread. 963 // See proc_task_readdir implementation in Linux. 964 result = Incomplete; 965 } 966 if (entry->d_ino && *entry->d_name >= '0' && *entry->d_name <= '9') 967 threads->push_back(internal_atoll(entry->d_name)); 968 } 969 970 // Now we are going to detect short-read or early EOF. In such cases Linux 971 // can return inconsistent list with missing alive threads. 972 // Code will just remember that the list can be incomplete but it will 973 // continue reads to return as much as possible. 974 if (!first_read) { 975 // The first one was a short-read by definition. 976 result = Incomplete; 977 } else if (read > buffer_.size() - 1024) { 978 // Read was close to the buffer size. So double the size and assume the 979 // worst. 980 buffer_.resize(buffer_.size() * 2); 981 result = Incomplete; 982 } else if (!threads->empty() && !IsAlive(threads->back())) { 983 // Maybe Linux early returned from read on terminated thread (!pid_alive) 984 // and failed to restore read position. 985 // See next_tid and proc_task_instantiate in Linux. 986 result = Incomplete; 987 } 988 } 989 } 990 991 bool ThreadLister::IsAlive(int tid) { 992 // /proc/%d/task/%d/status uses same call to detect alive threads as 993 // proc_task_readdir. See task_state implementation in Linux. 994 char path[80]; 995 internal_snprintf(path, sizeof(path), "/proc/%d/task/%d/status", pid_, tid); 996 if (!ReadFileToVector(path, &buffer_) || buffer_.empty()) 997 return false; 998 buffer_.push_back(0); 999 static const char kPrefix[] = "\nPPid:"; 1000 const char *field = internal_strstr(buffer_.data(), kPrefix); 1001 if (!field) 1002 return false; 1003 field += internal_strlen(kPrefix); 1004 return (int)internal_atoll(field) != 0; 1005 } 1006 1007 ThreadLister::~ThreadLister() { 1008 if (!internal_iserror(descriptor_)) 1009 internal_close(descriptor_); 1010 } 1011 #endif 1012 1013 #if SANITIZER_WORDSIZE == 32 1014 // Take care of unusable kernel area in top gigabyte. 1015 static uptr GetKernelAreaSize() { 1016 #if SANITIZER_LINUX && !SANITIZER_X32 1017 const uptr gbyte = 1UL << 30; 1018 1019 // Firstly check if there are writable segments 1020 // mapped to top gigabyte (e.g. stack). 1021 MemoryMappingLayout proc_maps(/*cache_enabled*/true); 1022 if (proc_maps.Error()) 1023 return 0; 1024 MemoryMappedSegment segment; 1025 while (proc_maps.Next(&segment)) { 1026 if ((segment.end >= 3 * gbyte) && segment.IsWritable()) return 0; 1027 } 1028 1029 #if !SANITIZER_ANDROID 1030 // Even if nothing is mapped, top Gb may still be accessible 1031 // if we are running on 64-bit kernel. 1032 // Uname may report misleading results if personality type 1033 // is modified (e.g. under schroot) so check this as well. 1034 struct utsname uname_info; 1035 int pers = personality(0xffffffffUL); 1036 if (!(pers & PER_MASK) && internal_uname(&uname_info) == 0 && 1037 internal_strstr(uname_info.machine, "64")) 1038 return 0; 1039 #endif // SANITIZER_ANDROID 1040 1041 // Top gigabyte is reserved for kernel. 1042 return gbyte; 1043 #else 1044 return 0; 1045 #endif // SANITIZER_LINUX && !SANITIZER_X32 1046 } 1047 #endif // SANITIZER_WORDSIZE == 32 1048 1049 uptr GetMaxVirtualAddress() { 1050 #if SANITIZER_NETBSD && defined(__x86_64__) 1051 return 0x7f7ffffff000ULL; // (0x00007f8000000000 - PAGE_SIZE) 1052 #elif SANITIZER_WORDSIZE == 64 1053 # if defined(__powerpc64__) || defined(__aarch64__) 1054 // On PowerPC64 we have two different address space layouts: 44- and 46-bit. 1055 // We somehow need to figure out which one we are using now and choose 1056 // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL. 1057 // Note that with 'ulimit -s unlimited' the stack is moved away from the top 1058 // of the address space, so simply checking the stack address is not enough. 1059 // This should (does) work for both PowerPC64 Endian modes. 1060 // Similarly, aarch64 has multiple address space layouts: 39, 42 and 47-bit. 1061 return (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1)) - 1; 1062 #elif SANITIZER_RISCV64 1063 return (1ULL << 38) - 1; 1064 # elif defined(__mips64) 1065 return (1ULL << 40) - 1; // 0x000000ffffffffffUL; 1066 # elif defined(__s390x__) 1067 return (1ULL << 53) - 1; // 0x001fffffffffffffUL; 1068 #elif defined(__sparc__) 1069 return ~(uptr)0; 1070 # else 1071 return (1ULL << 47) - 1; // 0x00007fffffffffffUL; 1072 # endif 1073 #else // SANITIZER_WORDSIZE == 32 1074 # if defined(__s390__) 1075 return (1ULL << 31) - 1; // 0x7fffffff; 1076 # else 1077 return (1ULL << 32) - 1; // 0xffffffff; 1078 # endif 1079 #endif // SANITIZER_WORDSIZE 1080 } 1081 1082 uptr GetMaxUserVirtualAddress() { 1083 uptr addr = GetMaxVirtualAddress(); 1084 #if SANITIZER_WORDSIZE == 32 && !defined(__s390__) 1085 if (!common_flags()->full_address_space) 1086 addr -= GetKernelAreaSize(); 1087 CHECK_LT(reinterpret_cast<uptr>(&addr), addr); 1088 #endif 1089 return addr; 1090 } 1091 1092 #if !SANITIZER_ANDROID 1093 uptr GetPageSize() { 1094 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__i386__)) && \ 1095 defined(EXEC_PAGESIZE) 1096 return EXEC_PAGESIZE; 1097 #elif SANITIZER_FREEBSD || SANITIZER_NETBSD 1098 // Use sysctl as sysconf can trigger interceptors internally. 1099 int pz = 0; 1100 uptr pzl = sizeof(pz); 1101 int mib[2] = {CTL_HW, HW_PAGESIZE}; 1102 int rv = internal_sysctl(mib, 2, &pz, &pzl, nullptr, 0); 1103 CHECK_EQ(rv, 0); 1104 return (uptr)pz; 1105 #elif SANITIZER_USE_GETAUXVAL 1106 return getauxval(AT_PAGESZ); 1107 #else 1108 return sysconf(_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy. 1109 #endif 1110 } 1111 #endif // !SANITIZER_ANDROID 1112 1113 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) { 1114 #if SANITIZER_SOLARIS 1115 const char *default_module_name = getexecname(); 1116 CHECK_NE(default_module_name, NULL); 1117 return internal_snprintf(buf, buf_len, "%s", default_module_name); 1118 #else 1119 #if SANITIZER_FREEBSD || SANITIZER_NETBSD 1120 #if SANITIZER_FREEBSD 1121 const int Mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1}; 1122 #else 1123 const int Mib[4] = {CTL_KERN, KERN_PROC_ARGS, -1, KERN_PROC_PATHNAME}; 1124 #endif 1125 const char *default_module_name = "kern.proc.pathname"; 1126 uptr Size = buf_len; 1127 bool IsErr = 1128 (internal_sysctl(Mib, ARRAY_SIZE(Mib), buf, &Size, NULL, 0) != 0); 1129 int readlink_error = IsErr ? errno : 0; 1130 uptr module_name_len = Size; 1131 #else 1132 const char *default_module_name = "/proc/self/exe"; 1133 uptr module_name_len = internal_readlink( 1134 default_module_name, buf, buf_len); 1135 int readlink_error; 1136 bool IsErr = internal_iserror(module_name_len, &readlink_error); 1137 #endif // SANITIZER_SOLARIS 1138 if (IsErr) { 1139 // We can't read binary name for some reason, assume it's unknown. 1140 Report("WARNING: reading executable name failed with errno %d, " 1141 "some stack frames may not be symbolized\n", readlink_error); 1142 module_name_len = internal_snprintf(buf, buf_len, "%s", 1143 default_module_name); 1144 CHECK_LT(module_name_len, buf_len); 1145 } 1146 return module_name_len; 1147 #endif 1148 } 1149 1150 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) { 1151 #if SANITIZER_LINUX 1152 char *tmpbuf; 1153 uptr tmpsize; 1154 uptr tmplen; 1155 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen, 1156 1024 * 1024)) { 1157 internal_strncpy(buf, tmpbuf, buf_len); 1158 UnmapOrDie(tmpbuf, tmpsize); 1159 return internal_strlen(buf); 1160 } 1161 #endif 1162 return ReadBinaryName(buf, buf_len); 1163 } 1164 1165 // Match full names of the form /path/to/base_name{-,.}* 1166 bool LibraryNameIs(const char *full_name, const char *base_name) { 1167 const char *name = full_name; 1168 // Strip path. 1169 while (*name != '\0') name++; 1170 while (name > full_name && *name != '/') name--; 1171 if (*name == '/') name++; 1172 uptr base_name_length = internal_strlen(base_name); 1173 if (internal_strncmp(name, base_name, base_name_length)) return false; 1174 return (name[base_name_length] == '-' || name[base_name_length] == '.'); 1175 } 1176 1177 #if !SANITIZER_ANDROID 1178 // Call cb for each region mapped by map. 1179 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) { 1180 CHECK_NE(map, nullptr); 1181 #if !SANITIZER_FREEBSD 1182 typedef ElfW(Phdr) Elf_Phdr; 1183 typedef ElfW(Ehdr) Elf_Ehdr; 1184 #endif // !SANITIZER_FREEBSD 1185 char *base = (char *)map->l_addr; 1186 Elf_Ehdr *ehdr = (Elf_Ehdr *)base; 1187 char *phdrs = base + ehdr->e_phoff; 1188 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize; 1189 1190 // Find the segment with the minimum base so we can "relocate" the p_vaddr 1191 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC 1192 // objects have a non-zero base. 1193 uptr preferred_base = (uptr)-1; 1194 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1195 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1196 if (phdr->p_type == PT_LOAD && preferred_base > (uptr)phdr->p_vaddr) 1197 preferred_base = (uptr)phdr->p_vaddr; 1198 } 1199 1200 // Compute the delta from the real base to get a relocation delta. 1201 sptr delta = (uptr)base - preferred_base; 1202 // Now we can figure out what the loader really mapped. 1203 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1204 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1205 if (phdr->p_type == PT_LOAD) { 1206 uptr seg_start = phdr->p_vaddr + delta; 1207 uptr seg_end = seg_start + phdr->p_memsz; 1208 // None of these values are aligned. We consider the ragged edges of the 1209 // load command as defined, since they are mapped from the file. 1210 seg_start = RoundDownTo(seg_start, GetPageSizeCached()); 1211 seg_end = RoundUpTo(seg_end, GetPageSizeCached()); 1212 cb((void *)seg_start, seg_end - seg_start); 1213 } 1214 } 1215 } 1216 #endif 1217 1218 #if SANITIZER_LINUX 1219 #if defined(__x86_64__) 1220 // We cannot use glibc's clone wrapper, because it messes with the child 1221 // task's TLS. It writes the PID and TID of the child task to its thread 1222 // descriptor, but in our case the child task shares the thread descriptor with 1223 // the parent (because we don't know how to allocate a new thread 1224 // descriptor to keep glibc happy). So the stock version of clone(), when 1225 // used with CLONE_VM, would end up corrupting the parent's thread descriptor. 1226 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1227 int *parent_tidptr, void *newtls, int *child_tidptr) { 1228 long long res; 1229 if (!fn || !child_stack) 1230 return -EINVAL; 1231 CHECK_EQ(0, (uptr)child_stack % 16); 1232 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1233 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1234 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1235 register void *r8 __asm__("r8") = newtls; 1236 register int *r10 __asm__("r10") = child_tidptr; 1237 __asm__ __volatile__( 1238 /* %rax = syscall(%rax = SYSCALL(clone), 1239 * %rdi = flags, 1240 * %rsi = child_stack, 1241 * %rdx = parent_tidptr, 1242 * %r8 = new_tls, 1243 * %r10 = child_tidptr) 1244 */ 1245 "syscall\n" 1246 1247 /* if (%rax != 0) 1248 * return; 1249 */ 1250 "testq %%rax,%%rax\n" 1251 "jnz 1f\n" 1252 1253 /* In the child. Terminate unwind chain. */ 1254 // XXX: We should also terminate the CFI unwind chain 1255 // here. Unfortunately clang 3.2 doesn't support the 1256 // necessary CFI directives, so we skip that part. 1257 "xorq %%rbp,%%rbp\n" 1258 1259 /* Call "fn(arg)". */ 1260 "popq %%rax\n" 1261 "popq %%rdi\n" 1262 "call *%%rax\n" 1263 1264 /* Call _exit(%rax). */ 1265 "movq %%rax,%%rdi\n" 1266 "movq %2,%%rax\n" 1267 "syscall\n" 1268 1269 /* Return to parent. */ 1270 "1:\n" 1271 : "=a" (res) 1272 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1273 "S"(child_stack), 1274 "D"(flags), 1275 "d"(parent_tidptr), 1276 "r"(r8), 1277 "r"(r10) 1278 : "memory", "r11", "rcx"); 1279 return res; 1280 } 1281 #elif defined(__mips__) 1282 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1283 int *parent_tidptr, void *newtls, int *child_tidptr) { 1284 long long res; 1285 if (!fn || !child_stack) 1286 return -EINVAL; 1287 CHECK_EQ(0, (uptr)child_stack % 16); 1288 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1289 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1290 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1291 register void *a3 __asm__("$7") = newtls; 1292 register int *a4 __asm__("$8") = child_tidptr; 1293 // We don't have proper CFI directives here because it requires alot of code 1294 // for very marginal benefits. 1295 __asm__ __volatile__( 1296 /* $v0 = syscall($v0 = __NR_clone, 1297 * $a0 = flags, 1298 * $a1 = child_stack, 1299 * $a2 = parent_tidptr, 1300 * $a3 = new_tls, 1301 * $a4 = child_tidptr) 1302 */ 1303 ".cprestore 16;\n" 1304 "move $4,%1;\n" 1305 "move $5,%2;\n" 1306 "move $6,%3;\n" 1307 "move $7,%4;\n" 1308 /* Store the fifth argument on stack 1309 * if we are using 32-bit abi. 1310 */ 1311 #if SANITIZER_WORDSIZE == 32 1312 "lw %5,16($29);\n" 1313 #else 1314 "move $8,%5;\n" 1315 #endif 1316 "li $2,%6;\n" 1317 "syscall;\n" 1318 1319 /* if ($v0 != 0) 1320 * return; 1321 */ 1322 "bnez $2,1f;\n" 1323 1324 /* Call "fn(arg)". */ 1325 #if SANITIZER_WORDSIZE == 32 1326 #ifdef __BIG_ENDIAN__ 1327 "lw $25,4($29);\n" 1328 "lw $4,12($29);\n" 1329 #else 1330 "lw $25,0($29);\n" 1331 "lw $4,8($29);\n" 1332 #endif 1333 #else 1334 "ld $25,0($29);\n" 1335 "ld $4,8($29);\n" 1336 #endif 1337 "jal $25;\n" 1338 1339 /* Call _exit($v0). */ 1340 "move $4,$2;\n" 1341 "li $2,%7;\n" 1342 "syscall;\n" 1343 1344 /* Return to parent. */ 1345 "1:\n" 1346 : "=r" (res) 1347 : "r"(flags), 1348 "r"(child_stack), 1349 "r"(parent_tidptr), 1350 "r"(a3), 1351 "r"(a4), 1352 "i"(__NR_clone), 1353 "i"(__NR_exit) 1354 : "memory", "$29" ); 1355 return res; 1356 } 1357 #elif SANITIZER_RISCV64 1358 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1359 int *parent_tidptr, void *newtls, int *child_tidptr) { 1360 if (!fn || !child_stack) 1361 return -EINVAL; 1362 1363 CHECK_EQ(0, (uptr)child_stack % 16); 1364 1365 register int res __asm__("a0"); 1366 register int __flags __asm__("a0") = flags; 1367 register void *__stack __asm__("a1") = child_stack; 1368 register int *__ptid __asm__("a2") = parent_tidptr; 1369 register void *__tls __asm__("a3") = newtls; 1370 register int *__ctid __asm__("a4") = child_tidptr; 1371 register int (*__fn)(void *) __asm__("a5") = fn; 1372 register void *__arg __asm__("a6") = arg; 1373 register int nr_clone __asm__("a7") = __NR_clone; 1374 1375 __asm__ __volatile__( 1376 "ecall\n" 1377 1378 /* if (a0 != 0) 1379 * return a0; 1380 */ 1381 "bnez a0, 1f\n" 1382 1383 // In the child, now. Call "fn(arg)". 1384 "mv a0, a6\n" 1385 "jalr a5\n" 1386 1387 // Call _exit(a0). 1388 "addi a7, zero, %9\n" 1389 "ecall\n" 1390 "1:\n" 1391 1392 : "=r"(res) 1393 : "0"(__flags), "r"(__stack), "r"(__ptid), "r"(__tls), "r"(__ctid), 1394 "r"(__fn), "r"(__arg), "r"(nr_clone), "i"(__NR_exit) 1395 : "memory"); 1396 return res; 1397 } 1398 #elif defined(__aarch64__) 1399 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1400 int *parent_tidptr, void *newtls, int *child_tidptr) { 1401 register long long res __asm__("x0"); 1402 if (!fn || !child_stack) 1403 return -EINVAL; 1404 CHECK_EQ(0, (uptr)child_stack % 16); 1405 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1406 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1407 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1408 1409 register int (*__fn)(void *) __asm__("x0") = fn; 1410 register void *__stack __asm__("x1") = child_stack; 1411 register int __flags __asm__("x2") = flags; 1412 register void *__arg __asm__("x3") = arg; 1413 register int *__ptid __asm__("x4") = parent_tidptr; 1414 register void *__tls __asm__("x5") = newtls; 1415 register int *__ctid __asm__("x6") = child_tidptr; 1416 1417 __asm__ __volatile__( 1418 "mov x0,x2\n" /* flags */ 1419 "mov x2,x4\n" /* ptid */ 1420 "mov x3,x5\n" /* tls */ 1421 "mov x4,x6\n" /* ctid */ 1422 "mov x8,%9\n" /* clone */ 1423 1424 "svc 0x0\n" 1425 1426 /* if (%r0 != 0) 1427 * return %r0; 1428 */ 1429 "cmp x0, #0\n" 1430 "bne 1f\n" 1431 1432 /* In the child, now. Call "fn(arg)". */ 1433 "ldp x1, x0, [sp], #16\n" 1434 "blr x1\n" 1435 1436 /* Call _exit(%r0). */ 1437 "mov x8, %10\n" 1438 "svc 0x0\n" 1439 "1:\n" 1440 1441 : "=r" (res) 1442 : "i"(-EINVAL), 1443 "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg), 1444 "r"(__ptid), "r"(__tls), "r"(__ctid), 1445 "i"(__NR_clone), "i"(__NR_exit) 1446 : "x30", "memory"); 1447 return res; 1448 } 1449 #elif defined(__powerpc64__) 1450 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1451 int *parent_tidptr, void *newtls, int *child_tidptr) { 1452 long long res; 1453 // Stack frame structure. 1454 #if SANITIZER_PPC64V1 1455 // Back chain == 0 (SP + 112) 1456 // Frame (112 bytes): 1457 // Parameter save area (SP + 48), 8 doublewords 1458 // TOC save area (SP + 40) 1459 // Link editor doubleword (SP + 32) 1460 // Compiler doubleword (SP + 24) 1461 // LR save area (SP + 16) 1462 // CR save area (SP + 8) 1463 // Back chain (SP + 0) 1464 # define FRAME_SIZE 112 1465 # define FRAME_TOC_SAVE_OFFSET 40 1466 #elif SANITIZER_PPC64V2 1467 // Back chain == 0 (SP + 32) 1468 // Frame (32 bytes): 1469 // TOC save area (SP + 24) 1470 // LR save area (SP + 16) 1471 // CR save area (SP + 8) 1472 // Back chain (SP + 0) 1473 # define FRAME_SIZE 32 1474 # define FRAME_TOC_SAVE_OFFSET 24 1475 #else 1476 # error "Unsupported PPC64 ABI" 1477 #endif 1478 if (!fn || !child_stack) 1479 return -EINVAL; 1480 CHECK_EQ(0, (uptr)child_stack % 16); 1481 1482 register int (*__fn)(void *) __asm__("r3") = fn; 1483 register void *__cstack __asm__("r4") = child_stack; 1484 register int __flags __asm__("r5") = flags; 1485 register void *__arg __asm__("r6") = arg; 1486 register int *__ptidptr __asm__("r7") = parent_tidptr; 1487 register void *__newtls __asm__("r8") = newtls; 1488 register int *__ctidptr __asm__("r9") = child_tidptr; 1489 1490 __asm__ __volatile__( 1491 /* fn and arg are saved across the syscall */ 1492 "mr 28, %5\n\t" 1493 "mr 27, %8\n\t" 1494 1495 /* syscall 1496 r0 == __NR_clone 1497 r3 == flags 1498 r4 == child_stack 1499 r5 == parent_tidptr 1500 r6 == newtls 1501 r7 == child_tidptr */ 1502 "mr 3, %7\n\t" 1503 "mr 5, %9\n\t" 1504 "mr 6, %10\n\t" 1505 "mr 7, %11\n\t" 1506 "li 0, %3\n\t" 1507 "sc\n\t" 1508 1509 /* Test if syscall was successful */ 1510 "cmpdi cr1, 3, 0\n\t" 1511 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t" 1512 "bne- cr1, 1f\n\t" 1513 1514 /* Set up stack frame */ 1515 "li 29, 0\n\t" 1516 "stdu 29, -8(1)\n\t" 1517 "stdu 1, -%12(1)\n\t" 1518 /* Do the function call */ 1519 "std 2, %13(1)\n\t" 1520 #if SANITIZER_PPC64V1 1521 "ld 0, 0(28)\n\t" 1522 "ld 2, 8(28)\n\t" 1523 "mtctr 0\n\t" 1524 #elif SANITIZER_PPC64V2 1525 "mr 12, 28\n\t" 1526 "mtctr 12\n\t" 1527 #else 1528 # error "Unsupported PPC64 ABI" 1529 #endif 1530 "mr 3, 27\n\t" 1531 "bctrl\n\t" 1532 "ld 2, %13(1)\n\t" 1533 1534 /* Call _exit(r3) */ 1535 "li 0, %4\n\t" 1536 "sc\n\t" 1537 1538 /* Return to parent */ 1539 "1:\n\t" 1540 "mr %0, 3\n\t" 1541 : "=r" (res) 1542 : "0" (-1), 1543 "i" (EINVAL), 1544 "i" (__NR_clone), 1545 "i" (__NR_exit), 1546 "r" (__fn), 1547 "r" (__cstack), 1548 "r" (__flags), 1549 "r" (__arg), 1550 "r" (__ptidptr), 1551 "r" (__newtls), 1552 "r" (__ctidptr), 1553 "i" (FRAME_SIZE), 1554 "i" (FRAME_TOC_SAVE_OFFSET) 1555 : "cr0", "cr1", "memory", "ctr", "r0", "r27", "r28", "r29"); 1556 return res; 1557 } 1558 #elif defined(__i386__) 1559 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1560 int *parent_tidptr, void *newtls, int *child_tidptr) { 1561 int res; 1562 if (!fn || !child_stack) 1563 return -EINVAL; 1564 CHECK_EQ(0, (uptr)child_stack % 16); 1565 child_stack = (char *)child_stack - 7 * sizeof(unsigned int); 1566 ((unsigned int *)child_stack)[0] = (uptr)flags; 1567 ((unsigned int *)child_stack)[1] = (uptr)0; 1568 ((unsigned int *)child_stack)[2] = (uptr)fn; 1569 ((unsigned int *)child_stack)[3] = (uptr)arg; 1570 __asm__ __volatile__( 1571 /* %eax = syscall(%eax = SYSCALL(clone), 1572 * %ebx = flags, 1573 * %ecx = child_stack, 1574 * %edx = parent_tidptr, 1575 * %esi = new_tls, 1576 * %edi = child_tidptr) 1577 */ 1578 1579 /* Obtain flags */ 1580 "movl (%%ecx), %%ebx\n" 1581 /* Do the system call */ 1582 "pushl %%ebx\n" 1583 "pushl %%esi\n" 1584 "pushl %%edi\n" 1585 /* Remember the flag value. */ 1586 "movl %%ebx, (%%ecx)\n" 1587 "int $0x80\n" 1588 "popl %%edi\n" 1589 "popl %%esi\n" 1590 "popl %%ebx\n" 1591 1592 /* if (%eax != 0) 1593 * return; 1594 */ 1595 1596 "test %%eax,%%eax\n" 1597 "jnz 1f\n" 1598 1599 /* terminate the stack frame */ 1600 "xorl %%ebp,%%ebp\n" 1601 /* Call FN. */ 1602 "call *%%ebx\n" 1603 #ifdef PIC 1604 "call here\n" 1605 "here:\n" 1606 "popl %%ebx\n" 1607 "addl $_GLOBAL_OFFSET_TABLE_+[.-here], %%ebx\n" 1608 #endif 1609 /* Call exit */ 1610 "movl %%eax, %%ebx\n" 1611 "movl %2, %%eax\n" 1612 "int $0x80\n" 1613 "1:\n" 1614 : "=a" (res) 1615 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1616 "c"(child_stack), 1617 "d"(parent_tidptr), 1618 "S"(newtls), 1619 "D"(child_tidptr) 1620 : "memory"); 1621 return res; 1622 } 1623 #elif defined(__arm__) 1624 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1625 int *parent_tidptr, void *newtls, int *child_tidptr) { 1626 unsigned int res; 1627 if (!fn || !child_stack) 1628 return -EINVAL; 1629 child_stack = (char *)child_stack - 2 * sizeof(unsigned int); 1630 ((unsigned int *)child_stack)[0] = (uptr)fn; 1631 ((unsigned int *)child_stack)[1] = (uptr)arg; 1632 register int r0 __asm__("r0") = flags; 1633 register void *r1 __asm__("r1") = child_stack; 1634 register int *r2 __asm__("r2") = parent_tidptr; 1635 register void *r3 __asm__("r3") = newtls; 1636 register int *r4 __asm__("r4") = child_tidptr; 1637 register int r7 __asm__("r7") = __NR_clone; 1638 1639 #if __ARM_ARCH > 4 || defined (__ARM_ARCH_4T__) 1640 # define ARCH_HAS_BX 1641 #endif 1642 #if __ARM_ARCH > 4 1643 # define ARCH_HAS_BLX 1644 #endif 1645 1646 #ifdef ARCH_HAS_BX 1647 # ifdef ARCH_HAS_BLX 1648 # define BLX(R) "blx " #R "\n" 1649 # else 1650 # define BLX(R) "mov lr, pc; bx " #R "\n" 1651 # endif 1652 #else 1653 # define BLX(R) "mov lr, pc; mov pc," #R "\n" 1654 #endif 1655 1656 __asm__ __volatile__( 1657 /* %r0 = syscall(%r7 = SYSCALL(clone), 1658 * %r0 = flags, 1659 * %r1 = child_stack, 1660 * %r2 = parent_tidptr, 1661 * %r3 = new_tls, 1662 * %r4 = child_tidptr) 1663 */ 1664 1665 /* Do the system call */ 1666 "swi 0x0\n" 1667 1668 /* if (%r0 != 0) 1669 * return %r0; 1670 */ 1671 "cmp r0, #0\n" 1672 "bne 1f\n" 1673 1674 /* In the child, now. Call "fn(arg)". */ 1675 "ldr r0, [sp, #4]\n" 1676 "ldr ip, [sp], #8\n" 1677 BLX(ip) 1678 /* Call _exit(%r0). */ 1679 "mov r7, %7\n" 1680 "swi 0x0\n" 1681 "1:\n" 1682 "mov %0, r0\n" 1683 : "=r"(res) 1684 : "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r7), 1685 "i"(__NR_exit) 1686 : "memory"); 1687 return res; 1688 } 1689 #endif 1690 #endif // SANITIZER_LINUX 1691 1692 #if SANITIZER_LINUX 1693 int internal_uname(struct utsname *buf) { 1694 return internal_syscall(SYSCALL(uname), buf); 1695 } 1696 #endif 1697 1698 #if SANITIZER_ANDROID 1699 #if __ANDROID_API__ < 21 1700 extern "C" __attribute__((weak)) int dl_iterate_phdr( 1701 int (*)(struct dl_phdr_info *, size_t, void *), void *); 1702 #endif 1703 1704 static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size, 1705 void *data) { 1706 // Any name starting with "lib" indicates a bug in L where library base names 1707 // are returned instead of paths. 1708 if (info->dlpi_name && info->dlpi_name[0] == 'l' && 1709 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') { 1710 *(bool *)data = true; 1711 return 1; 1712 } 1713 return 0; 1714 } 1715 1716 static atomic_uint32_t android_api_level; 1717 1718 static AndroidApiLevel AndroidDetectApiLevelStatic() { 1719 #if __ANDROID_API__ <= 19 1720 return ANDROID_KITKAT; 1721 #elif __ANDROID_API__ <= 22 1722 return ANDROID_LOLLIPOP_MR1; 1723 #else 1724 return ANDROID_POST_LOLLIPOP; 1725 #endif 1726 } 1727 1728 static AndroidApiLevel AndroidDetectApiLevel() { 1729 if (!&dl_iterate_phdr) 1730 return ANDROID_KITKAT; // K or lower 1731 bool base_name_seen = false; 1732 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen); 1733 if (base_name_seen) 1734 return ANDROID_LOLLIPOP_MR1; // L MR1 1735 return ANDROID_POST_LOLLIPOP; // post-L 1736 // Plain L (API level 21) is completely broken wrt ASan and not very 1737 // interesting to detect. 1738 } 1739 1740 extern "C" __attribute__((weak)) void* _DYNAMIC; 1741 1742 AndroidApiLevel AndroidGetApiLevel() { 1743 AndroidApiLevel level = 1744 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed); 1745 if (level) return level; 1746 level = &_DYNAMIC == nullptr ? AndroidDetectApiLevelStatic() 1747 : AndroidDetectApiLevel(); 1748 atomic_store(&android_api_level, level, memory_order_relaxed); 1749 return level; 1750 } 1751 1752 #endif 1753 1754 static HandleSignalMode GetHandleSignalModeImpl(int signum) { 1755 switch (signum) { 1756 case SIGABRT: 1757 return common_flags()->handle_abort; 1758 case SIGILL: 1759 return common_flags()->handle_sigill; 1760 case SIGTRAP: 1761 return common_flags()->handle_sigtrap; 1762 case SIGFPE: 1763 return common_flags()->handle_sigfpe; 1764 case SIGSEGV: 1765 return common_flags()->handle_segv; 1766 case SIGBUS: 1767 return common_flags()->handle_sigbus; 1768 } 1769 return kHandleSignalNo; 1770 } 1771 1772 HandleSignalMode GetHandleSignalMode(int signum) { 1773 HandleSignalMode result = GetHandleSignalModeImpl(signum); 1774 if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler) 1775 return kHandleSignalExclusive; 1776 return result; 1777 } 1778 1779 #if !SANITIZER_GO 1780 void *internal_start_thread(void *(*func)(void *arg), void *arg) { 1781 if (&real_pthread_create == 0) 1782 return nullptr; 1783 // Start the thread with signals blocked, otherwise it can steal user signals. 1784 ScopedBlockSignals block(nullptr); 1785 void *th; 1786 real_pthread_create(&th, nullptr, func, arg); 1787 return th; 1788 } 1789 1790 void internal_join_thread(void *th) { 1791 if (&real_pthread_join) 1792 real_pthread_join(th, nullptr); 1793 } 1794 #else 1795 void *internal_start_thread(void *(*func)(void *), void *arg) { return 0; } 1796 1797 void internal_join_thread(void *th) {} 1798 #endif 1799 1800 #if defined(__aarch64__) 1801 // Android headers in the older NDK releases miss this definition. 1802 struct __sanitizer_esr_context { 1803 struct _aarch64_ctx head; 1804 uint64_t esr; 1805 }; 1806 1807 static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) { 1808 static const u32 kEsrMagic = 0x45535201; 1809 u8 *aux = reinterpret_cast<u8 *>(ucontext->uc_mcontext.__reserved); 1810 while (true) { 1811 _aarch64_ctx *ctx = (_aarch64_ctx *)aux; 1812 if (ctx->size == 0) break; 1813 if (ctx->magic == kEsrMagic) { 1814 *esr = ((__sanitizer_esr_context *)ctx)->esr; 1815 return true; 1816 } 1817 aux += ctx->size; 1818 } 1819 return false; 1820 } 1821 #endif 1822 1823 using Context = ucontext_t; 1824 1825 SignalContext::WriteFlag SignalContext::GetWriteFlag() const { 1826 Context *ucontext = (Context *)context; 1827 #if defined(__x86_64__) || defined(__i386__) 1828 static const uptr PF_WRITE = 1U << 1; 1829 #if SANITIZER_FREEBSD 1830 uptr err = ucontext->uc_mcontext.mc_err; 1831 #elif SANITIZER_NETBSD 1832 uptr err = ucontext->uc_mcontext.__gregs[_REG_ERR]; 1833 #elif SANITIZER_SOLARIS && defined(__i386__) 1834 const int Err = 13; 1835 uptr err = ucontext->uc_mcontext.gregs[Err]; 1836 #else 1837 uptr err = ucontext->uc_mcontext.gregs[REG_ERR]; 1838 #endif // SANITIZER_FREEBSD 1839 return err & PF_WRITE ? Write : Read; 1840 #elif defined(__mips__) 1841 uint32_t *exception_source; 1842 uint32_t faulty_instruction; 1843 uint32_t op_code; 1844 1845 exception_source = (uint32_t *)ucontext->uc_mcontext.pc; 1846 faulty_instruction = (uint32_t)(*exception_source); 1847 1848 op_code = (faulty_instruction >> 26) & 0x3f; 1849 1850 // FIXME: Add support for FPU, microMIPS, DSP, MSA memory instructions. 1851 switch (op_code) { 1852 case 0x28: // sb 1853 case 0x29: // sh 1854 case 0x2b: // sw 1855 case 0x3f: // sd 1856 #if __mips_isa_rev < 6 1857 case 0x2c: // sdl 1858 case 0x2d: // sdr 1859 case 0x2a: // swl 1860 case 0x2e: // swr 1861 #endif 1862 return SignalContext::Write; 1863 1864 case 0x20: // lb 1865 case 0x24: // lbu 1866 case 0x21: // lh 1867 case 0x25: // lhu 1868 case 0x23: // lw 1869 case 0x27: // lwu 1870 case 0x37: // ld 1871 #if __mips_isa_rev < 6 1872 case 0x1a: // ldl 1873 case 0x1b: // ldr 1874 case 0x22: // lwl 1875 case 0x26: // lwr 1876 #endif 1877 return SignalContext::Read; 1878 #if __mips_isa_rev == 6 1879 case 0x3b: // pcrel 1880 op_code = (faulty_instruction >> 19) & 0x3; 1881 switch (op_code) { 1882 case 0x1: // lwpc 1883 case 0x2: // lwupc 1884 return SignalContext::Read; 1885 } 1886 #endif 1887 } 1888 return SignalContext::Unknown; 1889 #elif defined(__arm__) 1890 static const uptr FSR_WRITE = 1U << 11; 1891 uptr fsr = ucontext->uc_mcontext.error_code; 1892 return fsr & FSR_WRITE ? Write : Read; 1893 #elif defined(__aarch64__) 1894 static const u64 ESR_ELx_WNR = 1U << 6; 1895 u64 esr; 1896 if (!Aarch64GetESR(ucontext, &esr)) return Unknown; 1897 return esr & ESR_ELx_WNR ? Write : Read; 1898 #elif defined(__sparc__) 1899 // Decode the instruction to determine the access type. 1900 // From OpenSolaris $SRC/uts/sun4/os/trap.c (get_accesstype). 1901 #if SANITIZER_SOLARIS 1902 uptr pc = ucontext->uc_mcontext.gregs[REG_PC]; 1903 #else 1904 // Historical BSDism here. 1905 struct sigcontext *scontext = (struct sigcontext *)context; 1906 #if defined(__arch64__) 1907 uptr pc = scontext->sigc_regs.tpc; 1908 #else 1909 uptr pc = scontext->si_regs.pc; 1910 #endif 1911 #endif 1912 u32 instr = *(u32 *)pc; 1913 return (instr >> 21) & 1 ? Write: Read; 1914 #elif defined(__riscv) 1915 #if SANITIZER_FREEBSD 1916 unsigned long pc = ucontext->uc_mcontext.mc_gpregs.gp_sepc; 1917 #else 1918 unsigned long pc = ucontext->uc_mcontext.__gregs[REG_PC]; 1919 #endif 1920 unsigned faulty_instruction = *(uint16_t *)pc; 1921 1922 #if defined(__riscv_compressed) 1923 if ((faulty_instruction & 0x3) != 0x3) { // it's a compressed instruction 1924 // set op_bits to the instruction bits [1, 0, 15, 14, 13] 1925 unsigned op_bits = 1926 ((faulty_instruction & 0x3) << 3) | (faulty_instruction >> 13); 1927 unsigned rd = faulty_instruction & 0xF80; // bits 7-11, inclusive 1928 switch (op_bits) { 1929 case 0b10'010: // c.lwsp (rd != x0) 1930 #if __riscv_xlen == 64 1931 case 0b10'011: // c.ldsp (rd != x0) 1932 #endif 1933 return rd ? SignalContext::Read : SignalContext::Unknown; 1934 case 0b00'010: // c.lw 1935 #if __riscv_flen >= 32 && __riscv_xlen == 32 1936 case 0b10'011: // c.flwsp 1937 #endif 1938 #if __riscv_flen >= 32 || __riscv_xlen == 64 1939 case 0b00'011: // c.flw / c.ld 1940 #endif 1941 #if __riscv_flen == 64 1942 case 0b00'001: // c.fld 1943 case 0b10'001: // c.fldsp 1944 #endif 1945 return SignalContext::Read; 1946 case 0b00'110: // c.sw 1947 case 0b10'110: // c.swsp 1948 #if __riscv_flen >= 32 || __riscv_xlen == 64 1949 case 0b00'111: // c.fsw / c.sd 1950 case 0b10'111: // c.fswsp / c.sdsp 1951 #endif 1952 #if __riscv_flen == 64 1953 case 0b00'101: // c.fsd 1954 case 0b10'101: // c.fsdsp 1955 #endif 1956 return SignalContext::Write; 1957 default: 1958 return SignalContext::Unknown; 1959 } 1960 } 1961 #endif 1962 1963 unsigned opcode = faulty_instruction & 0x7f; // lower 7 bits 1964 unsigned funct3 = (faulty_instruction >> 12) & 0x7; // bits 12-14, inclusive 1965 switch (opcode) { 1966 case 0b0000011: // loads 1967 switch (funct3) { 1968 case 0b000: // lb 1969 case 0b001: // lh 1970 case 0b010: // lw 1971 #if __riscv_xlen == 64 1972 case 0b011: // ld 1973 #endif 1974 case 0b100: // lbu 1975 case 0b101: // lhu 1976 return SignalContext::Read; 1977 default: 1978 return SignalContext::Unknown; 1979 } 1980 case 0b0100011: // stores 1981 switch (funct3) { 1982 case 0b000: // sb 1983 case 0b001: // sh 1984 case 0b010: // sw 1985 #if __riscv_xlen == 64 1986 case 0b011: // sd 1987 #endif 1988 return SignalContext::Write; 1989 default: 1990 return SignalContext::Unknown; 1991 } 1992 #if __riscv_flen >= 32 1993 case 0b0000111: // floating-point loads 1994 switch (funct3) { 1995 case 0b010: // flw 1996 #if __riscv_flen == 64 1997 case 0b011: // fld 1998 #endif 1999 return SignalContext::Read; 2000 default: 2001 return SignalContext::Unknown; 2002 } 2003 case 0b0100111: // floating-point stores 2004 switch (funct3) { 2005 case 0b010: // fsw 2006 #if __riscv_flen == 64 2007 case 0b011: // fsd 2008 #endif 2009 return SignalContext::Write; 2010 default: 2011 return SignalContext::Unknown; 2012 } 2013 #endif 2014 default: 2015 return SignalContext::Unknown; 2016 } 2017 #else 2018 (void)ucontext; 2019 return Unknown; // FIXME: Implement. 2020 #endif 2021 } 2022 2023 bool SignalContext::IsTrueFaultingAddress() const { 2024 auto si = static_cast<const siginfo_t *>(siginfo); 2025 // SIGSEGV signals without a true fault address have si_code set to 128. 2026 return si->si_signo == SIGSEGV && si->si_code != 128; 2027 } 2028 2029 void SignalContext::DumpAllRegisters(void *context) { 2030 // FIXME: Implement this. 2031 } 2032 2033 static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) { 2034 #if SANITIZER_NETBSD 2035 // This covers all NetBSD architectures 2036 ucontext_t *ucontext = (ucontext_t *)context; 2037 *pc = _UC_MACHINE_PC(ucontext); 2038 *bp = _UC_MACHINE_FP(ucontext); 2039 *sp = _UC_MACHINE_SP(ucontext); 2040 #elif defined(__arm__) 2041 ucontext_t *ucontext = (ucontext_t*)context; 2042 *pc = ucontext->uc_mcontext.arm_pc; 2043 *bp = ucontext->uc_mcontext.arm_fp; 2044 *sp = ucontext->uc_mcontext.arm_sp; 2045 #elif defined(__aarch64__) 2046 ucontext_t *ucontext = (ucontext_t*)context; 2047 *pc = ucontext->uc_mcontext.pc; 2048 *bp = ucontext->uc_mcontext.regs[29]; 2049 *sp = ucontext->uc_mcontext.sp; 2050 #elif defined(__hppa__) 2051 ucontext_t *ucontext = (ucontext_t*)context; 2052 *pc = ucontext->uc_mcontext.sc_iaoq[0]; 2053 /* GCC uses %r3 whenever a frame pointer is needed. */ 2054 *bp = ucontext->uc_mcontext.sc_gr[3]; 2055 *sp = ucontext->uc_mcontext.sc_gr[30]; 2056 #elif defined(__x86_64__) 2057 # if SANITIZER_FREEBSD 2058 ucontext_t *ucontext = (ucontext_t*)context; 2059 *pc = ucontext->uc_mcontext.mc_rip; 2060 *bp = ucontext->uc_mcontext.mc_rbp; 2061 *sp = ucontext->uc_mcontext.mc_rsp; 2062 # else 2063 ucontext_t *ucontext = (ucontext_t*)context; 2064 *pc = ucontext->uc_mcontext.gregs[REG_RIP]; 2065 *bp = ucontext->uc_mcontext.gregs[REG_RBP]; 2066 *sp = ucontext->uc_mcontext.gregs[REG_RSP]; 2067 # endif 2068 #elif defined(__i386__) 2069 # if SANITIZER_FREEBSD 2070 ucontext_t *ucontext = (ucontext_t*)context; 2071 *pc = ucontext->uc_mcontext.mc_eip; 2072 *bp = ucontext->uc_mcontext.mc_ebp; 2073 *sp = ucontext->uc_mcontext.mc_esp; 2074 # else 2075 ucontext_t *ucontext = (ucontext_t*)context; 2076 # if SANITIZER_SOLARIS 2077 /* Use the numeric values: the symbolic ones are undefined by llvm 2078 include/llvm/Support/Solaris.h. */ 2079 # ifndef REG_EIP 2080 # define REG_EIP 14 // REG_PC 2081 # endif 2082 # ifndef REG_EBP 2083 # define REG_EBP 6 // REG_FP 2084 # endif 2085 # ifndef REG_UESP 2086 # define REG_UESP 17 // REG_SP 2087 # endif 2088 # endif 2089 *pc = ucontext->uc_mcontext.gregs[REG_EIP]; 2090 *bp = ucontext->uc_mcontext.gregs[REG_EBP]; 2091 *sp = ucontext->uc_mcontext.gregs[REG_UESP]; 2092 # endif 2093 #elif defined(__powerpc__) || defined(__powerpc64__) 2094 ucontext_t *ucontext = (ucontext_t*)context; 2095 *pc = ucontext->uc_mcontext.regs->nip; 2096 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1]; 2097 // The powerpc{,64}-linux ABIs do not specify r31 as the frame 2098 // pointer, but GCC always uses r31 when we need a frame pointer. 2099 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31]; 2100 #elif defined(__sparc__) 2101 #if defined(__arch64__) || defined(__sparcv9) 2102 #define STACK_BIAS 2047 2103 #else 2104 #define STACK_BIAS 0 2105 # endif 2106 # if SANITIZER_SOLARIS 2107 ucontext_t *ucontext = (ucontext_t *)context; 2108 *pc = ucontext->uc_mcontext.gregs[REG_PC]; 2109 *sp = ucontext->uc_mcontext.gregs[REG_O6] + STACK_BIAS; 2110 #else 2111 // Historical BSDism here. 2112 struct sigcontext *scontext = (struct sigcontext *)context; 2113 #if defined(__arch64__) 2114 *pc = scontext->sigc_regs.tpc; 2115 *sp = scontext->sigc_regs.u_regs[14] + STACK_BIAS; 2116 #else 2117 *pc = scontext->si_regs.pc; 2118 *sp = scontext->si_regs.u_regs[14]; 2119 #endif 2120 # endif 2121 *bp = (uptr)((uhwptr *)*sp)[14] + STACK_BIAS; 2122 #elif defined(__mips__) 2123 ucontext_t *ucontext = (ucontext_t*)context; 2124 *pc = ucontext->uc_mcontext.pc; 2125 *bp = ucontext->uc_mcontext.gregs[30]; 2126 *sp = ucontext->uc_mcontext.gregs[29]; 2127 #elif defined(__s390__) 2128 ucontext_t *ucontext = (ucontext_t*)context; 2129 # if defined(__s390x__) 2130 *pc = ucontext->uc_mcontext.psw.addr; 2131 # else 2132 *pc = ucontext->uc_mcontext.psw.addr & 0x7fffffff; 2133 # endif 2134 *bp = ucontext->uc_mcontext.gregs[11]; 2135 *sp = ucontext->uc_mcontext.gregs[15]; 2136 #elif defined(__riscv) 2137 ucontext_t *ucontext = (ucontext_t*)context; 2138 # if SANITIZER_FREEBSD 2139 *pc = ucontext->uc_mcontext.mc_gpregs.gp_sepc; 2140 *bp = ucontext->uc_mcontext.mc_gpregs.gp_s[0]; 2141 *sp = ucontext->uc_mcontext.mc_gpregs.gp_sp; 2142 # else 2143 *pc = ucontext->uc_mcontext.__gregs[REG_PC]; 2144 *bp = ucontext->uc_mcontext.__gregs[REG_S0]; 2145 *sp = ucontext->uc_mcontext.__gregs[REG_SP]; 2146 # endif 2147 # elif defined(__hexagon__) 2148 ucontext_t *ucontext = (ucontext_t *)context; 2149 *pc = ucontext->uc_mcontext.pc; 2150 *bp = ucontext->uc_mcontext.r30; 2151 *sp = ucontext->uc_mcontext.r29; 2152 # else 2153 # error "Unsupported arch" 2154 # endif 2155 } 2156 2157 void SignalContext::InitPcSpBp() { GetPcSpBp(context, &pc, &sp, &bp); } 2158 2159 void InitializePlatformEarly() { 2160 // Do nothing. 2161 } 2162 2163 void MaybeReexec() { 2164 // No need to re-exec on Linux. 2165 } 2166 2167 void CheckASLR() { 2168 #if SANITIZER_NETBSD 2169 int mib[3]; 2170 int paxflags; 2171 uptr len = sizeof(paxflags); 2172 2173 mib[0] = CTL_PROC; 2174 mib[1] = internal_getpid(); 2175 mib[2] = PROC_PID_PAXFLAGS; 2176 2177 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2178 Printf("sysctl failed\n"); 2179 Die(); 2180 } 2181 2182 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_ASLR)) { 2183 Printf("This sanitizer is not compatible with enabled ASLR.\n" 2184 "To disable ASLR, please run \"paxctl +a %s\" and try again.\n", 2185 GetArgv()[0]); 2186 Die(); 2187 } 2188 #elif SANITIZER_PPC64V2 2189 // Disable ASLR for Linux PPC64LE. 2190 int old_personality = personality(0xffffffff); 2191 if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) { 2192 VReport(1, "WARNING: Program is being run with address space layout " 2193 "randomization (ASLR) enabled which prevents the thread and " 2194 "memory sanitizers from working on powerpc64le.\n" 2195 "ASLR will be disabled and the program re-executed.\n"); 2196 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1); 2197 ReExec(); 2198 } 2199 #elif SANITIZER_FREEBSD 2200 int aslr_status; 2201 if (UNLIKELY(procctl(P_PID, 0, PROC_ASLR_STATUS, &aslr_status) == -1)) { 2202 // We're making things less 'dramatic' here since 2203 // the cmd is not necessarily guaranteed to be here 2204 // just yet regarding FreeBSD release 2205 return; 2206 } 2207 if ((aslr_status & PROC_ASLR_ACTIVE) != 0) { 2208 Printf("This sanitizer is not compatible with enabled ASLR " 2209 "and binaries compiled with PIE\n"); 2210 Die(); 2211 } 2212 #else 2213 // Do nothing 2214 #endif 2215 } 2216 2217 void CheckMPROTECT() { 2218 #if SANITIZER_NETBSD 2219 int mib[3]; 2220 int paxflags; 2221 uptr len = sizeof(paxflags); 2222 2223 mib[0] = CTL_PROC; 2224 mib[1] = internal_getpid(); 2225 mib[2] = PROC_PID_PAXFLAGS; 2226 2227 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2228 Printf("sysctl failed\n"); 2229 Die(); 2230 } 2231 2232 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_MPROTECT)) { 2233 Printf("This sanitizer is not compatible with enabled MPROTECT\n"); 2234 Die(); 2235 } 2236 #else 2237 // Do nothing 2238 #endif 2239 } 2240 2241 void CheckNoDeepBind(const char *filename, int flag) { 2242 #ifdef RTLD_DEEPBIND 2243 if (flag & RTLD_DEEPBIND) { 2244 Report( 2245 "You are trying to dlopen a %s shared library with RTLD_DEEPBIND flag" 2246 " which is incompatible with sanitizer runtime " 2247 "(see https://github.com/google/sanitizers/issues/611 for details" 2248 "). If you want to run %s library under sanitizers please remove " 2249 "RTLD_DEEPBIND from dlopen flags.\n", 2250 filename, filename); 2251 Die(); 2252 } 2253 #endif 2254 } 2255 2256 uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding, 2257 uptr *largest_gap_found, 2258 uptr *max_occupied_addr) { 2259 UNREACHABLE("FindAvailableMemoryRange is not available"); 2260 return 0; 2261 } 2262 2263 bool GetRandom(void *buffer, uptr length, bool blocking) { 2264 if (!buffer || !length || length > 256) 2265 return false; 2266 #if SANITIZER_USE_GETENTROPY 2267 uptr rnd = getentropy(buffer, length); 2268 int rverrno = 0; 2269 if (internal_iserror(rnd, &rverrno) && rverrno == EFAULT) 2270 return false; 2271 else if (rnd == 0) 2272 return true; 2273 #endif // SANITIZER_USE_GETENTROPY 2274 2275 #if SANITIZER_USE_GETRANDOM 2276 static atomic_uint8_t skip_getrandom_syscall; 2277 if (!atomic_load_relaxed(&skip_getrandom_syscall)) { 2278 // Up to 256 bytes, getrandom will not be interrupted. 2279 uptr res = internal_syscall(SYSCALL(getrandom), buffer, length, 2280 blocking ? 0 : GRND_NONBLOCK); 2281 int rverrno = 0; 2282 if (internal_iserror(res, &rverrno) && rverrno == ENOSYS) 2283 atomic_store_relaxed(&skip_getrandom_syscall, 1); 2284 else if (res == length) 2285 return true; 2286 } 2287 #endif // SANITIZER_USE_GETRANDOM 2288 // Up to 256 bytes, a read off /dev/urandom will not be interrupted. 2289 // blocking is moot here, O_NONBLOCK has no effect when opening /dev/urandom. 2290 uptr fd = internal_open("/dev/urandom", O_RDONLY); 2291 if (internal_iserror(fd)) 2292 return false; 2293 uptr res = internal_read(fd, buffer, length); 2294 if (internal_iserror(res)) 2295 return false; 2296 internal_close(fd); 2297 return true; 2298 } 2299 2300 } // namespace __sanitizer 2301 2302 #endif 2303