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_LINUX 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_LINUX 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_SPARC) && 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_LINUX 346 # if (SANITIZER_WORDSIZE == 64 || SANITIZER_X32) && !SANITIZER_SPARC 347 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 348 0); 349 # else 350 struct stat64 buf64; 351 int res = internal_syscall(SYSCALL(fstatat64), AT_FDCWD, (uptr)path, 352 (uptr)&buf64, 0); 353 stat64_to_stat(&buf64, (struct stat *)buf); 354 return res; 355 # endif 356 # else 357 struct stat64 buf64; 358 int res = internal_syscall(SYSCALL(stat64), path, &buf64); 359 stat64_to_stat(&buf64, (struct stat *)buf); 360 return res; 361 # endif 362 } 363 364 uptr internal_lstat(const char *path, void *buf) { 365 #if SANITIZER_FREEBSD 366 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 367 AT_SYMLINK_NOFOLLOW); 368 # elif SANITIZER_LINUX 369 # if (defined(_LP64) || SANITIZER_X32) && !SANITIZER_SPARC 370 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 371 AT_SYMLINK_NOFOLLOW); 372 # else 373 struct stat64 buf64; 374 int res = internal_syscall(SYSCALL(fstatat64), AT_FDCWD, (uptr)path, 375 (uptr)&buf64, AT_SYMLINK_NOFOLLOW); 376 stat64_to_stat(&buf64, (struct stat *)buf); 377 return res; 378 # endif 379 # else 380 struct stat64 buf64; 381 int res = internal_syscall(SYSCALL(lstat64), path, &buf64); 382 stat64_to_stat(&buf64, (struct stat *)buf); 383 return res; 384 # endif 385 } 386 387 uptr internal_fstat(fd_t fd, void *buf) { 388 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 389 #if SANITIZER_MIPS64 390 // For mips64, fstat syscall fills buffer in the format of kernel_stat 391 struct kernel_stat kbuf; 392 int res = internal_syscall(SYSCALL(fstat), fd, &kbuf); 393 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 394 return res; 395 # else 396 return internal_syscall(SYSCALL(fstat), fd, (uptr)buf); 397 # endif 398 #else 399 struct stat64 buf64; 400 int res = internal_syscall(SYSCALL(fstat64), fd, &buf64); 401 stat64_to_stat(&buf64, (struct stat *)buf); 402 return res; 403 #endif 404 } 405 406 uptr internal_filesize(fd_t fd) { 407 struct stat st; 408 if (internal_fstat(fd, &st)) 409 return -1; 410 return (uptr)st.st_size; 411 } 412 413 uptr internal_dup(int oldfd) { 414 return internal_syscall(SYSCALL(dup), oldfd); 415 } 416 417 uptr internal_dup2(int oldfd, int newfd) { 418 # if SANITIZER_LINUX 419 return internal_syscall(SYSCALL(dup3), oldfd, newfd, 0); 420 #else 421 return internal_syscall(SYSCALL(dup2), oldfd, newfd); 422 #endif 423 } 424 425 uptr internal_readlink(const char *path, char *buf, uptr bufsize) { 426 # if SANITIZER_LINUX 427 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD, (uptr)path, (uptr)buf, 428 bufsize); 429 #else 430 return internal_syscall(SYSCALL(readlink), (uptr)path, (uptr)buf, bufsize); 431 #endif 432 } 433 434 uptr internal_unlink(const char *path) { 435 # if SANITIZER_LINUX 436 return internal_syscall(SYSCALL(unlinkat), AT_FDCWD, (uptr)path, 0); 437 #else 438 return internal_syscall(SYSCALL(unlink), (uptr)path); 439 #endif 440 } 441 442 uptr internal_rename(const char *oldpath, const char *newpath) { 443 #if defined(__riscv) && defined(__linux__) 444 return internal_syscall(SYSCALL(renameat2), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 445 (uptr)newpath, 0); 446 # elif SANITIZER_LINUX 447 return internal_syscall(SYSCALL(renameat), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 448 (uptr)newpath); 449 # else 450 return internal_syscall(SYSCALL(rename), (uptr)oldpath, (uptr)newpath); 451 # endif 452 } 453 454 uptr internal_sched_yield() { 455 return internal_syscall(SYSCALL(sched_yield)); 456 } 457 458 void internal_usleep(u64 useconds) { 459 struct timespec ts; 460 ts.tv_sec = useconds / 1000000; 461 ts.tv_nsec = (useconds % 1000000) * 1000; 462 internal_syscall(SYSCALL(nanosleep), &ts, &ts); 463 } 464 465 uptr internal_execve(const char *filename, char *const argv[], 466 char *const envp[]) { 467 return internal_syscall(SYSCALL(execve), (uptr)filename, (uptr)argv, 468 (uptr)envp); 469 } 470 #endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD 471 472 #if !SANITIZER_NETBSD 473 void internal__exit(int exitcode) { 474 #if SANITIZER_FREEBSD || SANITIZER_SOLARIS 475 internal_syscall(SYSCALL(exit), exitcode); 476 #else 477 internal_syscall(SYSCALL(exit_group), exitcode); 478 #endif 479 Die(); // Unreachable. 480 } 481 #endif // !SANITIZER_NETBSD 482 483 // ----------------- sanitizer_common.h 484 bool FileExists(const char *filename) { 485 if (ShouldMockFailureToOpen(filename)) 486 return false; 487 struct stat st; 488 if (internal_stat(filename, &st)) 489 return false; 490 // Sanity check: filename is a regular file. 491 return S_ISREG(st.st_mode); 492 } 493 494 bool DirExists(const char *path) { 495 struct stat st; 496 if (internal_stat(path, &st)) 497 return false; 498 return S_ISDIR(st.st_mode); 499 } 500 501 # if !SANITIZER_NETBSD 502 tid_t GetTid() { 503 #if SANITIZER_FREEBSD 504 long Tid; 505 thr_self(&Tid); 506 return Tid; 507 #elif SANITIZER_SOLARIS 508 return thr_self(); 509 #else 510 return internal_syscall(SYSCALL(gettid)); 511 #endif 512 } 513 514 int TgKill(pid_t pid, tid_t tid, int sig) { 515 #if SANITIZER_LINUX 516 return internal_syscall(SYSCALL(tgkill), pid, tid, sig); 517 #elif SANITIZER_FREEBSD 518 return internal_syscall(SYSCALL(thr_kill2), pid, tid, sig); 519 #elif SANITIZER_SOLARIS 520 (void)pid; 521 return thr_kill(tid, sig); 522 #endif 523 } 524 #endif 525 526 #if SANITIZER_GLIBC 527 u64 NanoTime() { 528 kernel_timeval tv; 529 internal_memset(&tv, 0, sizeof(tv)); 530 internal_syscall(SYSCALL(gettimeofday), &tv, 0); 531 return (u64)tv.tv_sec * 1000 * 1000 * 1000 + tv.tv_usec * 1000; 532 } 533 // Used by real_clock_gettime. 534 uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) { 535 return internal_syscall(SYSCALL(clock_gettime), clk_id, tp); 536 } 537 #elif !SANITIZER_SOLARIS && !SANITIZER_NETBSD 538 u64 NanoTime() { 539 struct timespec ts; 540 clock_gettime(CLOCK_REALTIME, &ts); 541 return (u64)ts.tv_sec * 1000 * 1000 * 1000 + ts.tv_nsec; 542 } 543 #endif 544 545 // Like getenv, but reads env directly from /proc (on Linux) or parses the 546 // 'environ' array (on some others) and does not use libc. This function 547 // should be called first inside __asan_init. 548 const char *GetEnv(const char *name) { 549 #if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_SOLARIS 550 if (::environ != 0) { 551 uptr NameLen = internal_strlen(name); 552 for (char **Env = ::environ; *Env != 0; Env++) { 553 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=') 554 return (*Env) + NameLen + 1; 555 } 556 } 557 return 0; // Not found. 558 #elif SANITIZER_LINUX 559 static char *environ; 560 static uptr len; 561 static bool inited; 562 if (!inited) { 563 inited = true; 564 uptr environ_size; 565 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len)) 566 environ = nullptr; 567 } 568 if (!environ || len == 0) return nullptr; 569 uptr namelen = internal_strlen(name); 570 const char *p = environ; 571 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer 572 // proc file has the format NAME=value\0NAME=value\0NAME=value\0... 573 const char* endp = 574 (char*)internal_memchr(p, '\0', len - (p - environ)); 575 if (!endp) // this entry isn't NUL terminated 576 return nullptr; 577 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match. 578 return p + namelen + 1; // point after = 579 p = endp + 1; 580 } 581 return nullptr; // Not found. 582 #else 583 #error "Unsupported platform" 584 #endif 585 } 586 587 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD && !SANITIZER_GO 588 extern "C" { 589 SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end; 590 } 591 #endif 592 593 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD 594 static void ReadNullSepFileToArray(const char *path, char ***arr, 595 int arr_size) { 596 char *buff; 597 uptr buff_size; 598 uptr buff_len; 599 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray"); 600 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) { 601 (*arr)[0] = nullptr; 602 return; 603 } 604 (*arr)[0] = buff; 605 int count, i; 606 for (count = 1, i = 1; ; i++) { 607 if (buff[i] == 0) { 608 if (buff[i+1] == 0) break; 609 (*arr)[count] = &buff[i+1]; 610 CHECK_LE(count, arr_size - 1); // FIXME: make this more flexible. 611 count++; 612 } 613 } 614 (*arr)[count] = nullptr; 615 } 616 #endif 617 618 static void GetArgsAndEnv(char ***argv, char ***envp) { 619 #if SANITIZER_FREEBSD 620 // On FreeBSD, retrieving the argument and environment arrays is done via the 621 // kern.ps_strings sysctl, which returns a pointer to a structure containing 622 // this information. See also <sys/exec.h>. 623 ps_strings *pss; 624 uptr sz = sizeof(pss); 625 if (internal_sysctlbyname("kern.ps_strings", &pss, &sz, NULL, 0) == -1) { 626 Printf("sysctl kern.ps_strings failed\n"); 627 Die(); 628 } 629 *argv = pss->ps_argvstr; 630 *envp = pss->ps_envstr; 631 #elif SANITIZER_NETBSD 632 *argv = __ps_strings->ps_argvstr; 633 *envp = __ps_strings->ps_envstr; 634 #else // SANITIZER_FREEBSD 635 #if !SANITIZER_GO 636 if (&__libc_stack_end) { 637 uptr* stack_end = (uptr*)__libc_stack_end; 638 // Normally argc can be obtained from *stack_end, however, on ARM glibc's 639 // _start clobbers it: 640 // https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/arm/start.S;hb=refs/heads/release/2.31/master#l75 641 // Do not special-case ARM and infer argc from argv everywhere. 642 int argc = 0; 643 while (stack_end[argc + 1]) argc++; 644 *argv = (char**)(stack_end + 1); 645 *envp = (char**)(stack_end + argc + 2); 646 } else { 647 #endif // !SANITIZER_GO 648 static const int kMaxArgv = 2000, kMaxEnvp = 2000; 649 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv); 650 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp); 651 #if !SANITIZER_GO 652 } 653 #endif // !SANITIZER_GO 654 #endif // SANITIZER_FREEBSD 655 } 656 657 char **GetArgv() { 658 char **argv, **envp; 659 GetArgsAndEnv(&argv, &envp); 660 return argv; 661 } 662 663 char **GetEnviron() { 664 char **argv, **envp; 665 GetArgsAndEnv(&argv, &envp); 666 return envp; 667 } 668 669 #if !SANITIZER_SOLARIS 670 void FutexWait(atomic_uint32_t *p, u32 cmp) { 671 # if SANITIZER_FREEBSD 672 _umtx_op(p, UMTX_OP_WAIT_UINT, cmp, 0, 0); 673 # elif SANITIZER_NETBSD 674 sched_yield(); /* No userspace futex-like synchronization */ 675 # else 676 internal_syscall(SYSCALL(futex), (uptr)p, FUTEX_WAIT_PRIVATE, cmp, 0, 0, 0); 677 # endif 678 } 679 680 void FutexWake(atomic_uint32_t *p, u32 count) { 681 # if SANITIZER_FREEBSD 682 _umtx_op(p, UMTX_OP_WAKE, count, 0, 0); 683 # elif SANITIZER_NETBSD 684 /* No userspace futex-like synchronization */ 685 # else 686 internal_syscall(SYSCALL(futex), (uptr)p, FUTEX_WAKE_PRIVATE, count, 0, 0, 0); 687 # endif 688 } 689 690 # endif // !SANITIZER_SOLARIS 691 692 // ----------------- sanitizer_linux.h 693 // The actual size of this structure is specified by d_reclen. 694 // Note that getdents64 uses a different structure format. We only provide the 695 // 32-bit syscall here. 696 #if SANITIZER_NETBSD 697 // Not used 698 #else 699 struct linux_dirent { 700 # if SANITIZER_X32 || SANITIZER_LINUX 701 u64 d_ino; 702 u64 d_off; 703 # else 704 unsigned long d_ino; 705 unsigned long d_off; 706 # endif 707 unsigned short d_reclen; 708 # if SANITIZER_LINUX 709 unsigned char d_type; 710 # endif 711 char d_name[256]; 712 }; 713 #endif 714 715 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 716 // Syscall wrappers. 717 uptr internal_ptrace(int request, int pid, void *addr, void *data) { 718 return internal_syscall(SYSCALL(ptrace), request, pid, (uptr)addr, 719 (uptr)data); 720 } 721 722 uptr internal_waitpid(int pid, int *status, int options) { 723 return internal_syscall(SYSCALL(wait4), pid, (uptr)status, options, 724 0 /* rusage */); 725 } 726 727 uptr internal_getpid() { 728 return internal_syscall(SYSCALL(getpid)); 729 } 730 731 uptr internal_getppid() { 732 return internal_syscall(SYSCALL(getppid)); 733 } 734 735 int internal_dlinfo(void *handle, int request, void *p) { 736 #if SANITIZER_FREEBSD 737 return dlinfo(handle, request, p); 738 #else 739 UNIMPLEMENTED(); 740 #endif 741 } 742 743 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) { 744 #if SANITIZER_FREEBSD 745 return internal_syscall(SYSCALL(getdirentries), fd, (uptr)dirp, count, NULL); 746 # elif SANITIZER_LINUX 747 return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count); 748 # else 749 return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count); 750 # endif 751 } 752 753 uptr internal_lseek(fd_t fd, OFF_T offset, int whence) { 754 return internal_syscall(SYSCALL(lseek), fd, offset, whence); 755 } 756 757 #if SANITIZER_LINUX 758 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) { 759 return internal_syscall(SYSCALL(prctl), option, arg2, arg3, arg4, arg5); 760 } 761 #endif 762 763 uptr internal_sigaltstack(const void *ss, void *oss) { 764 return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss); 765 } 766 767 int internal_fork() { 768 # if SANITIZER_LINUX 769 # if SANITIZER_S390 770 return internal_syscall(SYSCALL(clone), 0, SIGCHLD); 771 # else 772 return internal_syscall(SYSCALL(clone), SIGCHLD, 0); 773 # endif 774 # else 775 return internal_syscall(SYSCALL(fork)); 776 # endif 777 } 778 779 #if SANITIZER_FREEBSD 780 int internal_sysctl(const int *name, unsigned int namelen, void *oldp, 781 uptr *oldlenp, const void *newp, uptr newlen) { 782 return internal_syscall(SYSCALL(__sysctl), name, namelen, oldp, 783 (size_t *)oldlenp, newp, (size_t)newlen); 784 } 785 786 int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp, 787 const void *newp, uptr newlen) { 788 // Note: this function can be called during startup, so we need to avoid 789 // calling any interceptable functions. On FreeBSD >= 1300045 sysctlbyname() 790 // is a real syscall, but for older versions it calls sysctlnametomib() 791 // followed by sysctl(). To avoid calling the intercepted version and 792 // asserting if this happens during startup, call the real sysctlnametomib() 793 // followed by internal_sysctl() if the syscall is not available. 794 #ifdef SYS___sysctlbyname 795 return internal_syscall(SYSCALL(__sysctlbyname), sname, 796 internal_strlen(sname), oldp, (size_t *)oldlenp, newp, 797 (size_t)newlen); 798 #else 799 static decltype(sysctlnametomib) *real_sysctlnametomib = nullptr; 800 if (!real_sysctlnametomib) 801 real_sysctlnametomib = 802 (decltype(sysctlnametomib) *)dlsym(RTLD_NEXT, "sysctlnametomib"); 803 CHECK(real_sysctlnametomib); 804 805 int oid[CTL_MAXNAME]; 806 size_t len = CTL_MAXNAME; 807 if (real_sysctlnametomib(sname, oid, &len) == -1) 808 return (-1); 809 return internal_sysctl(oid, len, oldp, oldlenp, newp, newlen); 810 #endif 811 } 812 #endif 813 814 #if SANITIZER_LINUX 815 #define SA_RESTORER 0x04000000 816 // Doesn't set sa_restorer if the caller did not set it, so use with caution 817 //(see below). 818 int internal_sigaction_norestorer(int signum, const void *act, void *oldact) { 819 __sanitizer_kernel_sigaction_t k_act, k_oldact; 820 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t)); 821 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t)); 822 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act; 823 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact; 824 if (u_act) { 825 k_act.handler = u_act->handler; 826 k_act.sigaction = u_act->sigaction; 827 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask, 828 sizeof(__sanitizer_kernel_sigset_t)); 829 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL). 830 k_act.sa_flags = u_act->sa_flags | SA_RESTORER; 831 // FIXME: most often sa_restorer is unset, however the kernel requires it 832 // to point to a valid signal restorer that calls the rt_sigreturn syscall. 833 // If sa_restorer passed to the kernel is NULL, the program may crash upon 834 // signal delivery or fail to unwind the stack in the signal handler. 835 // libc implementation of sigaction() passes its own restorer to 836 // rt_sigaction, so we need to do the same (we'll need to reimplement the 837 // restorers; for x86_64 the restorer address can be obtained from 838 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact). 839 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 840 k_act.sa_restorer = u_act->sa_restorer; 841 #endif 842 } 843 844 uptr result = internal_syscall(SYSCALL(rt_sigaction), (uptr)signum, 845 (uptr)(u_act ? &k_act : nullptr), 846 (uptr)(u_oldact ? &k_oldact : nullptr), 847 (uptr)sizeof(__sanitizer_kernel_sigset_t)); 848 849 if ((result == 0) && u_oldact) { 850 u_oldact->handler = k_oldact.handler; 851 u_oldact->sigaction = k_oldact.sigaction; 852 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask, 853 sizeof(__sanitizer_kernel_sigset_t)); 854 u_oldact->sa_flags = k_oldact.sa_flags; 855 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 856 u_oldact->sa_restorer = k_oldact.sa_restorer; 857 #endif 858 } 859 return result; 860 } 861 #endif // SANITIZER_LINUX 862 863 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set, 864 __sanitizer_sigset_t *oldset) { 865 #if SANITIZER_FREEBSD 866 return internal_syscall(SYSCALL(sigprocmask), how, set, oldset); 867 #else 868 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 869 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset; 870 return internal_syscall(SYSCALL(rt_sigprocmask), (uptr)how, (uptr)k_set, 871 (uptr)k_oldset, sizeof(__sanitizer_kernel_sigset_t)); 872 #endif 873 } 874 875 void internal_sigfillset(__sanitizer_sigset_t *set) { 876 internal_memset(set, 0xff, sizeof(*set)); 877 } 878 879 void internal_sigemptyset(__sanitizer_sigset_t *set) { 880 internal_memset(set, 0, sizeof(*set)); 881 } 882 883 #if SANITIZER_LINUX 884 void internal_sigdelset(__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 k_set->sig[idx] &= ~((uptr)1 << bit); 892 } 893 894 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 895 signum -= 1; 896 CHECK_GE(signum, 0); 897 CHECK_LT(signum, sizeof(*set) * 8); 898 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 899 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 900 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 901 return k_set->sig[idx] & ((uptr)1 << bit); 902 } 903 #elif SANITIZER_FREEBSD 904 uptr internal_procctl(int type, int id, int cmd, void *data) { 905 return internal_syscall(SYSCALL(procctl), type, id, cmd, data); 906 } 907 908 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 909 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 910 sigdelset(rset, signum); 911 } 912 913 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 914 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 915 return sigismember(rset, signum); 916 } 917 #endif 918 #endif // !SANITIZER_SOLARIS 919 920 #if !SANITIZER_NETBSD 921 // ThreadLister implementation. 922 ThreadLister::ThreadLister(pid_t pid) : pid_(pid), buffer_(4096) { 923 char task_directory_path[80]; 924 internal_snprintf(task_directory_path, sizeof(task_directory_path), 925 "/proc/%d/task/", pid); 926 descriptor_ = internal_open(task_directory_path, O_RDONLY | O_DIRECTORY); 927 if (internal_iserror(descriptor_)) { 928 Report("Can't open /proc/%d/task for reading.\n", pid); 929 } 930 } 931 932 ThreadLister::Result ThreadLister::ListThreads( 933 InternalMmapVector<tid_t> *threads) { 934 if (internal_iserror(descriptor_)) 935 return Error; 936 internal_lseek(descriptor_, 0, SEEK_SET); 937 threads->clear(); 938 939 Result result = Ok; 940 for (bool first_read = true;; first_read = false) { 941 // Resize to max capacity if it was downsized by IsAlive. 942 buffer_.resize(buffer_.capacity()); 943 CHECK_GE(buffer_.size(), 4096); 944 uptr read = internal_getdents( 945 descriptor_, (struct linux_dirent *)buffer_.data(), buffer_.size()); 946 if (!read) 947 return result; 948 if (internal_iserror(read)) { 949 Report("Can't read directory entries from /proc/%d/task.\n", pid_); 950 return Error; 951 } 952 953 for (uptr begin = (uptr)buffer_.data(), end = begin + read; begin < end;) { 954 struct linux_dirent *entry = (struct linux_dirent *)begin; 955 begin += entry->d_reclen; 956 if (entry->d_ino == 1) { 957 // Inode 1 is for bad blocks and also can be a reason for early return. 958 // Should be emitted if kernel tried to output terminating thread. 959 // See proc_task_readdir implementation in Linux. 960 result = Incomplete; 961 } 962 if (entry->d_ino && *entry->d_name >= '0' && *entry->d_name <= '9') 963 threads->push_back(internal_atoll(entry->d_name)); 964 } 965 966 // Now we are going to detect short-read or early EOF. In such cases Linux 967 // can return inconsistent list with missing alive threads. 968 // Code will just remember that the list can be incomplete but it will 969 // continue reads to return as much as possible. 970 if (!first_read) { 971 // The first one was a short-read by definition. 972 result = Incomplete; 973 } else if (read > buffer_.size() - 1024) { 974 // Read was close to the buffer size. So double the size and assume the 975 // worst. 976 buffer_.resize(buffer_.size() * 2); 977 result = Incomplete; 978 } else if (!threads->empty() && !IsAlive(threads->back())) { 979 // Maybe Linux early returned from read on terminated thread (!pid_alive) 980 // and failed to restore read position. 981 // See next_tid and proc_task_instantiate in Linux. 982 result = Incomplete; 983 } 984 } 985 } 986 987 bool ThreadLister::IsAlive(int tid) { 988 // /proc/%d/task/%d/status uses same call to detect alive threads as 989 // proc_task_readdir. See task_state implementation in Linux. 990 char path[80]; 991 internal_snprintf(path, sizeof(path), "/proc/%d/task/%d/status", pid_, tid); 992 if (!ReadFileToVector(path, &buffer_) || buffer_.empty()) 993 return false; 994 buffer_.push_back(0); 995 static const char kPrefix[] = "\nPPid:"; 996 const char *field = internal_strstr(buffer_.data(), kPrefix); 997 if (!field) 998 return false; 999 field += internal_strlen(kPrefix); 1000 return (int)internal_atoll(field) != 0; 1001 } 1002 1003 ThreadLister::~ThreadLister() { 1004 if (!internal_iserror(descriptor_)) 1005 internal_close(descriptor_); 1006 } 1007 #endif 1008 1009 #if SANITIZER_WORDSIZE == 32 1010 // Take care of unusable kernel area in top gigabyte. 1011 static uptr GetKernelAreaSize() { 1012 #if SANITIZER_LINUX && !SANITIZER_X32 1013 const uptr gbyte = 1UL << 30; 1014 1015 // Firstly check if there are writable segments 1016 // mapped to top gigabyte (e.g. stack). 1017 MemoryMappingLayout proc_maps(/*cache_enabled*/true); 1018 if (proc_maps.Error()) 1019 return 0; 1020 MemoryMappedSegment segment; 1021 while (proc_maps.Next(&segment)) { 1022 if ((segment.end >= 3 * gbyte) && segment.IsWritable()) return 0; 1023 } 1024 1025 #if !SANITIZER_ANDROID 1026 // Even if nothing is mapped, top Gb may still be accessible 1027 // if we are running on 64-bit kernel. 1028 // Uname may report misleading results if personality type 1029 // is modified (e.g. under schroot) so check this as well. 1030 struct utsname uname_info; 1031 int pers = personality(0xffffffffUL); 1032 if (!(pers & PER_MASK) && internal_uname(&uname_info) == 0 && 1033 internal_strstr(uname_info.machine, "64")) 1034 return 0; 1035 #endif // SANITIZER_ANDROID 1036 1037 // Top gigabyte is reserved for kernel. 1038 return gbyte; 1039 #else 1040 return 0; 1041 #endif // SANITIZER_LINUX && !SANITIZER_X32 1042 } 1043 #endif // SANITIZER_WORDSIZE == 32 1044 1045 uptr GetMaxVirtualAddress() { 1046 #if SANITIZER_NETBSD && defined(__x86_64__) 1047 return 0x7f7ffffff000ULL; // (0x00007f8000000000 - PAGE_SIZE) 1048 #elif SANITIZER_WORDSIZE == 64 1049 # if defined(__powerpc64__) || defined(__aarch64__) 1050 // On PowerPC64 we have two different address space layouts: 44- and 46-bit. 1051 // We somehow need to figure out which one we are using now and choose 1052 // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL. 1053 // Note that with 'ulimit -s unlimited' the stack is moved away from the top 1054 // of the address space, so simply checking the stack address is not enough. 1055 // This should (does) work for both PowerPC64 Endian modes. 1056 // Similarly, aarch64 has multiple address space layouts: 39, 42 and 47-bit. 1057 return (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1)) - 1; 1058 #elif SANITIZER_RISCV64 1059 return (1ULL << 38) - 1; 1060 # elif defined(__mips64) 1061 return (1ULL << 40) - 1; // 0x000000ffffffffffUL; 1062 # elif defined(__s390x__) 1063 return (1ULL << 53) - 1; // 0x001fffffffffffffUL; 1064 #elif defined(__sparc__) 1065 return ~(uptr)0; 1066 # else 1067 return (1ULL << 47) - 1; // 0x00007fffffffffffUL; 1068 # endif 1069 #else // SANITIZER_WORDSIZE == 32 1070 # if defined(__s390__) 1071 return (1ULL << 31) - 1; // 0x7fffffff; 1072 # else 1073 return (1ULL << 32) - 1; // 0xffffffff; 1074 # endif 1075 #endif // SANITIZER_WORDSIZE 1076 } 1077 1078 uptr GetMaxUserVirtualAddress() { 1079 uptr addr = GetMaxVirtualAddress(); 1080 #if SANITIZER_WORDSIZE == 32 && !defined(__s390__) 1081 if (!common_flags()->full_address_space) 1082 addr -= GetKernelAreaSize(); 1083 CHECK_LT(reinterpret_cast<uptr>(&addr), addr); 1084 #endif 1085 return addr; 1086 } 1087 1088 #if !SANITIZER_ANDROID 1089 uptr GetPageSize() { 1090 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__i386__)) && \ 1091 defined(EXEC_PAGESIZE) 1092 return EXEC_PAGESIZE; 1093 #elif SANITIZER_FREEBSD || SANITIZER_NETBSD 1094 // Use sysctl as sysconf can trigger interceptors internally. 1095 int pz = 0; 1096 uptr pzl = sizeof(pz); 1097 int mib[2] = {CTL_HW, HW_PAGESIZE}; 1098 int rv = internal_sysctl(mib, 2, &pz, &pzl, nullptr, 0); 1099 CHECK_EQ(rv, 0); 1100 return (uptr)pz; 1101 #elif SANITIZER_USE_GETAUXVAL 1102 return getauxval(AT_PAGESZ); 1103 #else 1104 return sysconf(_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy. 1105 #endif 1106 } 1107 #endif // !SANITIZER_ANDROID 1108 1109 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) { 1110 #if SANITIZER_SOLARIS 1111 const char *default_module_name = getexecname(); 1112 CHECK_NE(default_module_name, NULL); 1113 return internal_snprintf(buf, buf_len, "%s", default_module_name); 1114 #else 1115 #if SANITIZER_FREEBSD || SANITIZER_NETBSD 1116 #if SANITIZER_FREEBSD 1117 const int Mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1}; 1118 #else 1119 const int Mib[4] = {CTL_KERN, KERN_PROC_ARGS, -1, KERN_PROC_PATHNAME}; 1120 #endif 1121 const char *default_module_name = "kern.proc.pathname"; 1122 uptr Size = buf_len; 1123 bool IsErr = 1124 (internal_sysctl(Mib, ARRAY_SIZE(Mib), buf, &Size, NULL, 0) != 0); 1125 int readlink_error = IsErr ? errno : 0; 1126 uptr module_name_len = Size; 1127 #else 1128 const char *default_module_name = "/proc/self/exe"; 1129 uptr module_name_len = internal_readlink( 1130 default_module_name, buf, buf_len); 1131 int readlink_error; 1132 bool IsErr = internal_iserror(module_name_len, &readlink_error); 1133 #endif // SANITIZER_SOLARIS 1134 if (IsErr) { 1135 // We can't read binary name for some reason, assume it's unknown. 1136 Report("WARNING: reading executable name failed with errno %d, " 1137 "some stack frames may not be symbolized\n", readlink_error); 1138 module_name_len = internal_snprintf(buf, buf_len, "%s", 1139 default_module_name); 1140 CHECK_LT(module_name_len, buf_len); 1141 } 1142 return module_name_len; 1143 #endif 1144 } 1145 1146 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) { 1147 #if SANITIZER_LINUX 1148 char *tmpbuf; 1149 uptr tmpsize; 1150 uptr tmplen; 1151 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen, 1152 1024 * 1024)) { 1153 internal_strncpy(buf, tmpbuf, buf_len); 1154 UnmapOrDie(tmpbuf, tmpsize); 1155 return internal_strlen(buf); 1156 } 1157 #endif 1158 return ReadBinaryName(buf, buf_len); 1159 } 1160 1161 // Match full names of the form /path/to/base_name{-,.}* 1162 bool LibraryNameIs(const char *full_name, const char *base_name) { 1163 const char *name = full_name; 1164 // Strip path. 1165 while (*name != '\0') name++; 1166 while (name > full_name && *name != '/') name--; 1167 if (*name == '/') name++; 1168 uptr base_name_length = internal_strlen(base_name); 1169 if (internal_strncmp(name, base_name, base_name_length)) return false; 1170 return (name[base_name_length] == '-' || name[base_name_length] == '.'); 1171 } 1172 1173 #if !SANITIZER_ANDROID 1174 // Call cb for each region mapped by map. 1175 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) { 1176 CHECK_NE(map, nullptr); 1177 #if !SANITIZER_FREEBSD 1178 typedef ElfW(Phdr) Elf_Phdr; 1179 typedef ElfW(Ehdr) Elf_Ehdr; 1180 #endif // !SANITIZER_FREEBSD 1181 char *base = (char *)map->l_addr; 1182 Elf_Ehdr *ehdr = (Elf_Ehdr *)base; 1183 char *phdrs = base + ehdr->e_phoff; 1184 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize; 1185 1186 // Find the segment with the minimum base so we can "relocate" the p_vaddr 1187 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC 1188 // objects have a non-zero base. 1189 uptr preferred_base = (uptr)-1; 1190 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1191 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1192 if (phdr->p_type == PT_LOAD && preferred_base > (uptr)phdr->p_vaddr) 1193 preferred_base = (uptr)phdr->p_vaddr; 1194 } 1195 1196 // Compute the delta from the real base to get a relocation delta. 1197 sptr delta = (uptr)base - preferred_base; 1198 // Now we can figure out what the loader really mapped. 1199 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1200 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1201 if (phdr->p_type == PT_LOAD) { 1202 uptr seg_start = phdr->p_vaddr + delta; 1203 uptr seg_end = seg_start + phdr->p_memsz; 1204 // None of these values are aligned. We consider the ragged edges of the 1205 // load command as defined, since they are mapped from the file. 1206 seg_start = RoundDownTo(seg_start, GetPageSizeCached()); 1207 seg_end = RoundUpTo(seg_end, GetPageSizeCached()); 1208 cb((void *)seg_start, seg_end - seg_start); 1209 } 1210 } 1211 } 1212 #endif 1213 1214 #if SANITIZER_LINUX 1215 #if defined(__x86_64__) 1216 // We cannot use glibc's clone wrapper, because it messes with the child 1217 // task's TLS. It writes the PID and TID of the child task to its thread 1218 // descriptor, but in our case the child task shares the thread descriptor with 1219 // the parent (because we don't know how to allocate a new thread 1220 // descriptor to keep glibc happy). So the stock version of clone(), when 1221 // used with CLONE_VM, would end up corrupting the parent's thread descriptor. 1222 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1223 int *parent_tidptr, void *newtls, int *child_tidptr) { 1224 long long res; 1225 if (!fn || !child_stack) 1226 return -EINVAL; 1227 CHECK_EQ(0, (uptr)child_stack % 16); 1228 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1229 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1230 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1231 register void *r8 __asm__("r8") = newtls; 1232 register int *r10 __asm__("r10") = child_tidptr; 1233 __asm__ __volatile__( 1234 /* %rax = syscall(%rax = SYSCALL(clone), 1235 * %rdi = flags, 1236 * %rsi = child_stack, 1237 * %rdx = parent_tidptr, 1238 * %r8 = new_tls, 1239 * %r10 = child_tidptr) 1240 */ 1241 "syscall\n" 1242 1243 /* if (%rax != 0) 1244 * return; 1245 */ 1246 "testq %%rax,%%rax\n" 1247 "jnz 1f\n" 1248 1249 /* In the child. Terminate unwind chain. */ 1250 // XXX: We should also terminate the CFI unwind chain 1251 // here. Unfortunately clang 3.2 doesn't support the 1252 // necessary CFI directives, so we skip that part. 1253 "xorq %%rbp,%%rbp\n" 1254 1255 /* Call "fn(arg)". */ 1256 "popq %%rax\n" 1257 "popq %%rdi\n" 1258 "call *%%rax\n" 1259 1260 /* Call _exit(%rax). */ 1261 "movq %%rax,%%rdi\n" 1262 "movq %2,%%rax\n" 1263 "syscall\n" 1264 1265 /* Return to parent. */ 1266 "1:\n" 1267 : "=a" (res) 1268 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1269 "S"(child_stack), 1270 "D"(flags), 1271 "d"(parent_tidptr), 1272 "r"(r8), 1273 "r"(r10) 1274 : "memory", "r11", "rcx"); 1275 return res; 1276 } 1277 #elif defined(__mips__) 1278 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1279 int *parent_tidptr, void *newtls, int *child_tidptr) { 1280 long long res; 1281 if (!fn || !child_stack) 1282 return -EINVAL; 1283 CHECK_EQ(0, (uptr)child_stack % 16); 1284 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1285 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1286 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1287 register void *a3 __asm__("$7") = newtls; 1288 register int *a4 __asm__("$8") = child_tidptr; 1289 // We don't have proper CFI directives here because it requires alot of code 1290 // for very marginal benefits. 1291 __asm__ __volatile__( 1292 /* $v0 = syscall($v0 = __NR_clone, 1293 * $a0 = flags, 1294 * $a1 = child_stack, 1295 * $a2 = parent_tidptr, 1296 * $a3 = new_tls, 1297 * $a4 = child_tidptr) 1298 */ 1299 ".cprestore 16;\n" 1300 "move $4,%1;\n" 1301 "move $5,%2;\n" 1302 "move $6,%3;\n" 1303 "move $7,%4;\n" 1304 /* Store the fifth argument on stack 1305 * if we are using 32-bit abi. 1306 */ 1307 #if SANITIZER_WORDSIZE == 32 1308 "lw %5,16($29);\n" 1309 #else 1310 "move $8,%5;\n" 1311 #endif 1312 "li $2,%6;\n" 1313 "syscall;\n" 1314 1315 /* if ($v0 != 0) 1316 * return; 1317 */ 1318 "bnez $2,1f;\n" 1319 1320 /* Call "fn(arg)". */ 1321 #if SANITIZER_WORDSIZE == 32 1322 #ifdef __BIG_ENDIAN__ 1323 "lw $25,4($29);\n" 1324 "lw $4,12($29);\n" 1325 #else 1326 "lw $25,0($29);\n" 1327 "lw $4,8($29);\n" 1328 #endif 1329 #else 1330 "ld $25,0($29);\n" 1331 "ld $4,8($29);\n" 1332 #endif 1333 "jal $25;\n" 1334 1335 /* Call _exit($v0). */ 1336 "move $4,$2;\n" 1337 "li $2,%7;\n" 1338 "syscall;\n" 1339 1340 /* Return to parent. */ 1341 "1:\n" 1342 : "=r" (res) 1343 : "r"(flags), 1344 "r"(child_stack), 1345 "r"(parent_tidptr), 1346 "r"(a3), 1347 "r"(a4), 1348 "i"(__NR_clone), 1349 "i"(__NR_exit) 1350 : "memory", "$29" ); 1351 return res; 1352 } 1353 #elif SANITIZER_RISCV64 1354 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1355 int *parent_tidptr, void *newtls, int *child_tidptr) { 1356 if (!fn || !child_stack) 1357 return -EINVAL; 1358 1359 CHECK_EQ(0, (uptr)child_stack % 16); 1360 1361 register int res __asm__("a0"); 1362 register int __flags __asm__("a0") = flags; 1363 register void *__stack __asm__("a1") = child_stack; 1364 register int *__ptid __asm__("a2") = parent_tidptr; 1365 register void *__tls __asm__("a3") = newtls; 1366 register int *__ctid __asm__("a4") = child_tidptr; 1367 register int (*__fn)(void *) __asm__("a5") = fn; 1368 register void *__arg __asm__("a6") = arg; 1369 register int nr_clone __asm__("a7") = __NR_clone; 1370 1371 __asm__ __volatile__( 1372 "ecall\n" 1373 1374 /* if (a0 != 0) 1375 * return a0; 1376 */ 1377 "bnez a0, 1f\n" 1378 1379 // In the child, now. Call "fn(arg)". 1380 "mv a0, a6\n" 1381 "jalr a5\n" 1382 1383 // Call _exit(a0). 1384 "addi a7, zero, %9\n" 1385 "ecall\n" 1386 "1:\n" 1387 1388 : "=r"(res) 1389 : "0"(__flags), "r"(__stack), "r"(__ptid), "r"(__tls), "r"(__ctid), 1390 "r"(__fn), "r"(__arg), "r"(nr_clone), "i"(__NR_exit) 1391 : "memory"); 1392 return res; 1393 } 1394 #elif defined(__aarch64__) 1395 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1396 int *parent_tidptr, void *newtls, int *child_tidptr) { 1397 register long long res __asm__("x0"); 1398 if (!fn || !child_stack) 1399 return -EINVAL; 1400 CHECK_EQ(0, (uptr)child_stack % 16); 1401 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1402 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1403 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1404 1405 register int (*__fn)(void *) __asm__("x0") = fn; 1406 register void *__stack __asm__("x1") = child_stack; 1407 register int __flags __asm__("x2") = flags; 1408 register void *__arg __asm__("x3") = arg; 1409 register int *__ptid __asm__("x4") = parent_tidptr; 1410 register void *__tls __asm__("x5") = newtls; 1411 register int *__ctid __asm__("x6") = child_tidptr; 1412 1413 __asm__ __volatile__( 1414 "mov x0,x2\n" /* flags */ 1415 "mov x2,x4\n" /* ptid */ 1416 "mov x3,x5\n" /* tls */ 1417 "mov x4,x6\n" /* ctid */ 1418 "mov x8,%9\n" /* clone */ 1419 1420 "svc 0x0\n" 1421 1422 /* if (%r0 != 0) 1423 * return %r0; 1424 */ 1425 "cmp x0, #0\n" 1426 "bne 1f\n" 1427 1428 /* In the child, now. Call "fn(arg)". */ 1429 "ldp x1, x0, [sp], #16\n" 1430 "blr x1\n" 1431 1432 /* Call _exit(%r0). */ 1433 "mov x8, %10\n" 1434 "svc 0x0\n" 1435 "1:\n" 1436 1437 : "=r" (res) 1438 : "i"(-EINVAL), 1439 "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg), 1440 "r"(__ptid), "r"(__tls), "r"(__ctid), 1441 "i"(__NR_clone), "i"(__NR_exit) 1442 : "x30", "memory"); 1443 return res; 1444 } 1445 #elif defined(__powerpc64__) 1446 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1447 int *parent_tidptr, void *newtls, int *child_tidptr) { 1448 long long res; 1449 // Stack frame structure. 1450 #if SANITIZER_PPC64V1 1451 // Back chain == 0 (SP + 112) 1452 // Frame (112 bytes): 1453 // Parameter save area (SP + 48), 8 doublewords 1454 // TOC save area (SP + 40) 1455 // Link editor doubleword (SP + 32) 1456 // Compiler doubleword (SP + 24) 1457 // LR save area (SP + 16) 1458 // CR save area (SP + 8) 1459 // Back chain (SP + 0) 1460 # define FRAME_SIZE 112 1461 # define FRAME_TOC_SAVE_OFFSET 40 1462 #elif SANITIZER_PPC64V2 1463 // Back chain == 0 (SP + 32) 1464 // Frame (32 bytes): 1465 // TOC save area (SP + 24) 1466 // LR save area (SP + 16) 1467 // CR save area (SP + 8) 1468 // Back chain (SP + 0) 1469 # define FRAME_SIZE 32 1470 # define FRAME_TOC_SAVE_OFFSET 24 1471 #else 1472 # error "Unsupported PPC64 ABI" 1473 #endif 1474 if (!fn || !child_stack) 1475 return -EINVAL; 1476 CHECK_EQ(0, (uptr)child_stack % 16); 1477 1478 register int (*__fn)(void *) __asm__("r3") = fn; 1479 register void *__cstack __asm__("r4") = child_stack; 1480 register int __flags __asm__("r5") = flags; 1481 register void *__arg __asm__("r6") = arg; 1482 register int *__ptidptr __asm__("r7") = parent_tidptr; 1483 register void *__newtls __asm__("r8") = newtls; 1484 register int *__ctidptr __asm__("r9") = child_tidptr; 1485 1486 __asm__ __volatile__( 1487 /* fn and arg are saved across the syscall */ 1488 "mr 28, %5\n\t" 1489 "mr 27, %8\n\t" 1490 1491 /* syscall 1492 r0 == __NR_clone 1493 r3 == flags 1494 r4 == child_stack 1495 r5 == parent_tidptr 1496 r6 == newtls 1497 r7 == child_tidptr */ 1498 "mr 3, %7\n\t" 1499 "mr 5, %9\n\t" 1500 "mr 6, %10\n\t" 1501 "mr 7, %11\n\t" 1502 "li 0, %3\n\t" 1503 "sc\n\t" 1504 1505 /* Test if syscall was successful */ 1506 "cmpdi cr1, 3, 0\n\t" 1507 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t" 1508 "bne- cr1, 1f\n\t" 1509 1510 /* Set up stack frame */ 1511 "li 29, 0\n\t" 1512 "stdu 29, -8(1)\n\t" 1513 "stdu 1, -%12(1)\n\t" 1514 /* Do the function call */ 1515 "std 2, %13(1)\n\t" 1516 #if SANITIZER_PPC64V1 1517 "ld 0, 0(28)\n\t" 1518 "ld 2, 8(28)\n\t" 1519 "mtctr 0\n\t" 1520 #elif SANITIZER_PPC64V2 1521 "mr 12, 28\n\t" 1522 "mtctr 12\n\t" 1523 #else 1524 # error "Unsupported PPC64 ABI" 1525 #endif 1526 "mr 3, 27\n\t" 1527 "bctrl\n\t" 1528 "ld 2, %13(1)\n\t" 1529 1530 /* Call _exit(r3) */ 1531 "li 0, %4\n\t" 1532 "sc\n\t" 1533 1534 /* Return to parent */ 1535 "1:\n\t" 1536 "mr %0, 3\n\t" 1537 : "=r" (res) 1538 : "0" (-1), 1539 "i" (EINVAL), 1540 "i" (__NR_clone), 1541 "i" (__NR_exit), 1542 "r" (__fn), 1543 "r" (__cstack), 1544 "r" (__flags), 1545 "r" (__arg), 1546 "r" (__ptidptr), 1547 "r" (__newtls), 1548 "r" (__ctidptr), 1549 "i" (FRAME_SIZE), 1550 "i" (FRAME_TOC_SAVE_OFFSET) 1551 : "cr0", "cr1", "memory", "ctr", "r0", "r27", "r28", "r29"); 1552 return res; 1553 } 1554 #elif defined(__i386__) 1555 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1556 int *parent_tidptr, void *newtls, int *child_tidptr) { 1557 int res; 1558 if (!fn || !child_stack) 1559 return -EINVAL; 1560 CHECK_EQ(0, (uptr)child_stack % 16); 1561 child_stack = (char *)child_stack - 7 * sizeof(unsigned int); 1562 ((unsigned int *)child_stack)[0] = (uptr)flags; 1563 ((unsigned int *)child_stack)[1] = (uptr)0; 1564 ((unsigned int *)child_stack)[2] = (uptr)fn; 1565 ((unsigned int *)child_stack)[3] = (uptr)arg; 1566 __asm__ __volatile__( 1567 /* %eax = syscall(%eax = SYSCALL(clone), 1568 * %ebx = flags, 1569 * %ecx = child_stack, 1570 * %edx = parent_tidptr, 1571 * %esi = new_tls, 1572 * %edi = child_tidptr) 1573 */ 1574 1575 /* Obtain flags */ 1576 "movl (%%ecx), %%ebx\n" 1577 /* Do the system call */ 1578 "pushl %%ebx\n" 1579 "pushl %%esi\n" 1580 "pushl %%edi\n" 1581 /* Remember the flag value. */ 1582 "movl %%ebx, (%%ecx)\n" 1583 "int $0x80\n" 1584 "popl %%edi\n" 1585 "popl %%esi\n" 1586 "popl %%ebx\n" 1587 1588 /* if (%eax != 0) 1589 * return; 1590 */ 1591 1592 "test %%eax,%%eax\n" 1593 "jnz 1f\n" 1594 1595 /* terminate the stack frame */ 1596 "xorl %%ebp,%%ebp\n" 1597 /* Call FN. */ 1598 "call *%%ebx\n" 1599 #ifdef PIC 1600 "call here\n" 1601 "here:\n" 1602 "popl %%ebx\n" 1603 "addl $_GLOBAL_OFFSET_TABLE_+[.-here], %%ebx\n" 1604 #endif 1605 /* Call exit */ 1606 "movl %%eax, %%ebx\n" 1607 "movl %2, %%eax\n" 1608 "int $0x80\n" 1609 "1:\n" 1610 : "=a" (res) 1611 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1612 "c"(child_stack), 1613 "d"(parent_tidptr), 1614 "S"(newtls), 1615 "D"(child_tidptr) 1616 : "memory"); 1617 return res; 1618 } 1619 #elif defined(__arm__) 1620 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1621 int *parent_tidptr, void *newtls, int *child_tidptr) { 1622 unsigned int res; 1623 if (!fn || !child_stack) 1624 return -EINVAL; 1625 child_stack = (char *)child_stack - 2 * sizeof(unsigned int); 1626 ((unsigned int *)child_stack)[0] = (uptr)fn; 1627 ((unsigned int *)child_stack)[1] = (uptr)arg; 1628 register int r0 __asm__("r0") = flags; 1629 register void *r1 __asm__("r1") = child_stack; 1630 register int *r2 __asm__("r2") = parent_tidptr; 1631 register void *r3 __asm__("r3") = newtls; 1632 register int *r4 __asm__("r4") = child_tidptr; 1633 register int r7 __asm__("r7") = __NR_clone; 1634 1635 #if __ARM_ARCH > 4 || defined (__ARM_ARCH_4T__) 1636 # define ARCH_HAS_BX 1637 #endif 1638 #if __ARM_ARCH > 4 1639 # define ARCH_HAS_BLX 1640 #endif 1641 1642 #ifdef ARCH_HAS_BX 1643 # ifdef ARCH_HAS_BLX 1644 # define BLX(R) "blx " #R "\n" 1645 # else 1646 # define BLX(R) "mov lr, pc; bx " #R "\n" 1647 # endif 1648 #else 1649 # define BLX(R) "mov lr, pc; mov pc," #R "\n" 1650 #endif 1651 1652 __asm__ __volatile__( 1653 /* %r0 = syscall(%r7 = SYSCALL(clone), 1654 * %r0 = flags, 1655 * %r1 = child_stack, 1656 * %r2 = parent_tidptr, 1657 * %r3 = new_tls, 1658 * %r4 = child_tidptr) 1659 */ 1660 1661 /* Do the system call */ 1662 "swi 0x0\n" 1663 1664 /* if (%r0 != 0) 1665 * return %r0; 1666 */ 1667 "cmp r0, #0\n" 1668 "bne 1f\n" 1669 1670 /* In the child, now. Call "fn(arg)". */ 1671 "ldr r0, [sp, #4]\n" 1672 "ldr ip, [sp], #8\n" 1673 BLX(ip) 1674 /* Call _exit(%r0). */ 1675 "mov r7, %7\n" 1676 "swi 0x0\n" 1677 "1:\n" 1678 "mov %0, r0\n" 1679 : "=r"(res) 1680 : "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r7), 1681 "i"(__NR_exit) 1682 : "memory"); 1683 return res; 1684 } 1685 #endif 1686 #endif // SANITIZER_LINUX 1687 1688 #if SANITIZER_LINUX 1689 int internal_uname(struct utsname *buf) { 1690 return internal_syscall(SYSCALL(uname), buf); 1691 } 1692 #endif 1693 1694 #if SANITIZER_ANDROID 1695 #if __ANDROID_API__ < 21 1696 extern "C" __attribute__((weak)) int dl_iterate_phdr( 1697 int (*)(struct dl_phdr_info *, size_t, void *), void *); 1698 #endif 1699 1700 static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size, 1701 void *data) { 1702 // Any name starting with "lib" indicates a bug in L where library base names 1703 // are returned instead of paths. 1704 if (info->dlpi_name && info->dlpi_name[0] == 'l' && 1705 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') { 1706 *(bool *)data = true; 1707 return 1; 1708 } 1709 return 0; 1710 } 1711 1712 static atomic_uint32_t android_api_level; 1713 1714 static AndroidApiLevel AndroidDetectApiLevelStatic() { 1715 #if __ANDROID_API__ <= 19 1716 return ANDROID_KITKAT; 1717 #elif __ANDROID_API__ <= 22 1718 return ANDROID_LOLLIPOP_MR1; 1719 #else 1720 return ANDROID_POST_LOLLIPOP; 1721 #endif 1722 } 1723 1724 static AndroidApiLevel AndroidDetectApiLevel() { 1725 if (!&dl_iterate_phdr) 1726 return ANDROID_KITKAT; // K or lower 1727 bool base_name_seen = false; 1728 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen); 1729 if (base_name_seen) 1730 return ANDROID_LOLLIPOP_MR1; // L MR1 1731 return ANDROID_POST_LOLLIPOP; // post-L 1732 // Plain L (API level 21) is completely broken wrt ASan and not very 1733 // interesting to detect. 1734 } 1735 1736 extern "C" __attribute__((weak)) void* _DYNAMIC; 1737 1738 AndroidApiLevel AndroidGetApiLevel() { 1739 AndroidApiLevel level = 1740 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed); 1741 if (level) return level; 1742 level = &_DYNAMIC == nullptr ? AndroidDetectApiLevelStatic() 1743 : AndroidDetectApiLevel(); 1744 atomic_store(&android_api_level, level, memory_order_relaxed); 1745 return level; 1746 } 1747 1748 #endif 1749 1750 static HandleSignalMode GetHandleSignalModeImpl(int signum) { 1751 switch (signum) { 1752 case SIGABRT: 1753 return common_flags()->handle_abort; 1754 case SIGILL: 1755 return common_flags()->handle_sigill; 1756 case SIGTRAP: 1757 return common_flags()->handle_sigtrap; 1758 case SIGFPE: 1759 return common_flags()->handle_sigfpe; 1760 case SIGSEGV: 1761 return common_flags()->handle_segv; 1762 case SIGBUS: 1763 return common_flags()->handle_sigbus; 1764 } 1765 return kHandleSignalNo; 1766 } 1767 1768 HandleSignalMode GetHandleSignalMode(int signum) { 1769 HandleSignalMode result = GetHandleSignalModeImpl(signum); 1770 if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler) 1771 return kHandleSignalExclusive; 1772 return result; 1773 } 1774 1775 #if !SANITIZER_GO 1776 void *internal_start_thread(void *(*func)(void *arg), void *arg) { 1777 if (&real_pthread_create == 0) 1778 return nullptr; 1779 // Start the thread with signals blocked, otherwise it can steal user signals. 1780 ScopedBlockSignals block(nullptr); 1781 void *th; 1782 real_pthread_create(&th, nullptr, func, arg); 1783 return th; 1784 } 1785 1786 void internal_join_thread(void *th) { 1787 if (&real_pthread_join) 1788 real_pthread_join(th, nullptr); 1789 } 1790 #else 1791 void *internal_start_thread(void *(*func)(void *), void *arg) { return 0; } 1792 1793 void internal_join_thread(void *th) {} 1794 #endif 1795 1796 #if SANITIZER_LINUX && defined(__aarch64__) 1797 // Android headers in the older NDK releases miss this definition. 1798 struct __sanitizer_esr_context { 1799 struct _aarch64_ctx head; 1800 uint64_t esr; 1801 }; 1802 1803 static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) { 1804 static const u32 kEsrMagic = 0x45535201; 1805 u8 *aux = reinterpret_cast<u8 *>(ucontext->uc_mcontext.__reserved); 1806 while (true) { 1807 _aarch64_ctx *ctx = (_aarch64_ctx *)aux; 1808 if (ctx->size == 0) break; 1809 if (ctx->magic == kEsrMagic) { 1810 *esr = ((__sanitizer_esr_context *)ctx)->esr; 1811 return true; 1812 } 1813 aux += ctx->size; 1814 } 1815 return false; 1816 } 1817 #elif SANITIZER_FREEBSD && defined(__aarch64__) 1818 // FreeBSD doesn't provide ESR in the ucontext. 1819 static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) { 1820 return false; 1821 } 1822 #endif 1823 1824 using Context = ucontext_t; 1825 1826 SignalContext::WriteFlag SignalContext::GetWriteFlag() const { 1827 Context *ucontext = (Context *)context; 1828 #if defined(__x86_64__) || defined(__i386__) 1829 static const uptr PF_WRITE = 1U << 1; 1830 #if SANITIZER_FREEBSD 1831 uptr err = ucontext->uc_mcontext.mc_err; 1832 #elif SANITIZER_NETBSD 1833 uptr err = ucontext->uc_mcontext.__gregs[_REG_ERR]; 1834 #elif SANITIZER_SOLARIS && defined(__i386__) 1835 const int Err = 13; 1836 uptr err = ucontext->uc_mcontext.gregs[Err]; 1837 #else 1838 uptr err = ucontext->uc_mcontext.gregs[REG_ERR]; 1839 #endif // SANITIZER_FREEBSD 1840 return err & PF_WRITE ? Write : Read; 1841 #elif defined(__mips__) 1842 uint32_t *exception_source; 1843 uint32_t faulty_instruction; 1844 uint32_t op_code; 1845 1846 exception_source = (uint32_t *)ucontext->uc_mcontext.pc; 1847 faulty_instruction = (uint32_t)(*exception_source); 1848 1849 op_code = (faulty_instruction >> 26) & 0x3f; 1850 1851 // FIXME: Add support for FPU, microMIPS, DSP, MSA memory instructions. 1852 switch (op_code) { 1853 case 0x28: // sb 1854 case 0x29: // sh 1855 case 0x2b: // sw 1856 case 0x3f: // sd 1857 #if __mips_isa_rev < 6 1858 case 0x2c: // sdl 1859 case 0x2d: // sdr 1860 case 0x2a: // swl 1861 case 0x2e: // swr 1862 #endif 1863 return SignalContext::Write; 1864 1865 case 0x20: // lb 1866 case 0x24: // lbu 1867 case 0x21: // lh 1868 case 0x25: // lhu 1869 case 0x23: // lw 1870 case 0x27: // lwu 1871 case 0x37: // ld 1872 #if __mips_isa_rev < 6 1873 case 0x1a: // ldl 1874 case 0x1b: // ldr 1875 case 0x22: // lwl 1876 case 0x26: // lwr 1877 #endif 1878 return SignalContext::Read; 1879 #if __mips_isa_rev == 6 1880 case 0x3b: // pcrel 1881 op_code = (faulty_instruction >> 19) & 0x3; 1882 switch (op_code) { 1883 case 0x1: // lwpc 1884 case 0x2: // lwupc 1885 return SignalContext::Read; 1886 } 1887 #endif 1888 } 1889 return SignalContext::Unknown; 1890 #elif defined(__arm__) 1891 static const uptr FSR_WRITE = 1U << 11; 1892 uptr fsr = ucontext->uc_mcontext.error_code; 1893 return fsr & FSR_WRITE ? Write : Read; 1894 #elif defined(__aarch64__) 1895 static const u64 ESR_ELx_WNR = 1U << 6; 1896 u64 esr; 1897 if (!Aarch64GetESR(ucontext, &esr)) return Unknown; 1898 return esr & ESR_ELx_WNR ? Write : Read; 1899 #elif defined(__sparc__) 1900 // Decode the instruction to determine the access type. 1901 // From OpenSolaris $SRC/uts/sun4/os/trap.c (get_accesstype). 1902 #if SANITIZER_SOLARIS 1903 uptr pc = ucontext->uc_mcontext.gregs[REG_PC]; 1904 #else 1905 // Historical BSDism here. 1906 struct sigcontext *scontext = (struct sigcontext *)context; 1907 #if defined(__arch64__) 1908 uptr pc = scontext->sigc_regs.tpc; 1909 #else 1910 uptr pc = scontext->si_regs.pc; 1911 #endif 1912 #endif 1913 u32 instr = *(u32 *)pc; 1914 return (instr >> 21) & 1 ? Write: Read; 1915 #elif defined(__riscv) 1916 #if SANITIZER_FREEBSD 1917 unsigned long pc = ucontext->uc_mcontext.mc_gpregs.gp_sepc; 1918 #else 1919 unsigned long pc = ucontext->uc_mcontext.__gregs[REG_PC]; 1920 #endif 1921 unsigned faulty_instruction = *(uint16_t *)pc; 1922 1923 #if defined(__riscv_compressed) 1924 if ((faulty_instruction & 0x3) != 0x3) { // it's a compressed instruction 1925 // set op_bits to the instruction bits [1, 0, 15, 14, 13] 1926 unsigned op_bits = 1927 ((faulty_instruction & 0x3) << 3) | (faulty_instruction >> 13); 1928 unsigned rd = faulty_instruction & 0xF80; // bits 7-11, inclusive 1929 switch (op_bits) { 1930 case 0b10'010: // c.lwsp (rd != x0) 1931 #if __riscv_xlen == 64 1932 case 0b10'011: // c.ldsp (rd != x0) 1933 #endif 1934 return rd ? SignalContext::Read : SignalContext::Unknown; 1935 case 0b00'010: // c.lw 1936 #if __riscv_flen >= 32 && __riscv_xlen == 32 1937 case 0b10'011: // c.flwsp 1938 #endif 1939 #if __riscv_flen >= 32 || __riscv_xlen == 64 1940 case 0b00'011: // c.flw / c.ld 1941 #endif 1942 #if __riscv_flen == 64 1943 case 0b00'001: // c.fld 1944 case 0b10'001: // c.fldsp 1945 #endif 1946 return SignalContext::Read; 1947 case 0b00'110: // c.sw 1948 case 0b10'110: // c.swsp 1949 #if __riscv_flen >= 32 || __riscv_xlen == 64 1950 case 0b00'111: // c.fsw / c.sd 1951 case 0b10'111: // c.fswsp / c.sdsp 1952 #endif 1953 #if __riscv_flen == 64 1954 case 0b00'101: // c.fsd 1955 case 0b10'101: // c.fsdsp 1956 #endif 1957 return SignalContext::Write; 1958 default: 1959 return SignalContext::Unknown; 1960 } 1961 } 1962 #endif 1963 1964 unsigned opcode = faulty_instruction & 0x7f; // lower 7 bits 1965 unsigned funct3 = (faulty_instruction >> 12) & 0x7; // bits 12-14, inclusive 1966 switch (opcode) { 1967 case 0b0000011: // loads 1968 switch (funct3) { 1969 case 0b000: // lb 1970 case 0b001: // lh 1971 case 0b010: // lw 1972 #if __riscv_xlen == 64 1973 case 0b011: // ld 1974 #endif 1975 case 0b100: // lbu 1976 case 0b101: // lhu 1977 return SignalContext::Read; 1978 default: 1979 return SignalContext::Unknown; 1980 } 1981 case 0b0100011: // stores 1982 switch (funct3) { 1983 case 0b000: // sb 1984 case 0b001: // sh 1985 case 0b010: // sw 1986 #if __riscv_xlen == 64 1987 case 0b011: // sd 1988 #endif 1989 return SignalContext::Write; 1990 default: 1991 return SignalContext::Unknown; 1992 } 1993 #if __riscv_flen >= 32 1994 case 0b0000111: // floating-point loads 1995 switch (funct3) { 1996 case 0b010: // flw 1997 #if __riscv_flen == 64 1998 case 0b011: // fld 1999 #endif 2000 return SignalContext::Read; 2001 default: 2002 return SignalContext::Unknown; 2003 } 2004 case 0b0100111: // floating-point stores 2005 switch (funct3) { 2006 case 0b010: // fsw 2007 #if __riscv_flen == 64 2008 case 0b011: // fsd 2009 #endif 2010 return SignalContext::Write; 2011 default: 2012 return SignalContext::Unknown; 2013 } 2014 #endif 2015 default: 2016 return SignalContext::Unknown; 2017 } 2018 #else 2019 (void)ucontext; 2020 return Unknown; // FIXME: Implement. 2021 #endif 2022 } 2023 2024 bool SignalContext::IsTrueFaultingAddress() const { 2025 auto si = static_cast<const siginfo_t *>(siginfo); 2026 // SIGSEGV signals without a true fault address have si_code set to 128. 2027 return si->si_signo == SIGSEGV && si->si_code != 128; 2028 } 2029 2030 void SignalContext::DumpAllRegisters(void *context) { 2031 // FIXME: Implement this. 2032 } 2033 2034 static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) { 2035 #if SANITIZER_NETBSD 2036 // This covers all NetBSD architectures 2037 ucontext_t *ucontext = (ucontext_t *)context; 2038 *pc = _UC_MACHINE_PC(ucontext); 2039 *bp = _UC_MACHINE_FP(ucontext); 2040 *sp = _UC_MACHINE_SP(ucontext); 2041 #elif defined(__arm__) 2042 ucontext_t *ucontext = (ucontext_t*)context; 2043 *pc = ucontext->uc_mcontext.arm_pc; 2044 *bp = ucontext->uc_mcontext.arm_fp; 2045 *sp = ucontext->uc_mcontext.arm_sp; 2046 #elif defined(__aarch64__) 2047 # if SANITIZER_FREEBSD 2048 ucontext_t *ucontext = (ucontext_t*)context; 2049 *pc = ucontext->uc_mcontext.mc_gpregs.gp_elr; 2050 *bp = ucontext->uc_mcontext.mc_gpregs.gp_x[29]; 2051 *sp = ucontext->uc_mcontext.mc_gpregs.gp_sp; 2052 # else 2053 ucontext_t *ucontext = (ucontext_t*)context; 2054 *pc = ucontext->uc_mcontext.pc; 2055 *bp = ucontext->uc_mcontext.regs[29]; 2056 *sp = ucontext->uc_mcontext.sp; 2057 # endif 2058 #elif defined(__hppa__) 2059 ucontext_t *ucontext = (ucontext_t*)context; 2060 *pc = ucontext->uc_mcontext.sc_iaoq[0]; 2061 /* GCC uses %r3 whenever a frame pointer is needed. */ 2062 *bp = ucontext->uc_mcontext.sc_gr[3]; 2063 *sp = ucontext->uc_mcontext.sc_gr[30]; 2064 #elif defined(__x86_64__) 2065 # if SANITIZER_FREEBSD 2066 ucontext_t *ucontext = (ucontext_t*)context; 2067 *pc = ucontext->uc_mcontext.mc_rip; 2068 *bp = ucontext->uc_mcontext.mc_rbp; 2069 *sp = ucontext->uc_mcontext.mc_rsp; 2070 # else 2071 ucontext_t *ucontext = (ucontext_t*)context; 2072 *pc = ucontext->uc_mcontext.gregs[REG_RIP]; 2073 *bp = ucontext->uc_mcontext.gregs[REG_RBP]; 2074 *sp = ucontext->uc_mcontext.gregs[REG_RSP]; 2075 # endif 2076 #elif defined(__i386__) 2077 # if SANITIZER_FREEBSD 2078 ucontext_t *ucontext = (ucontext_t*)context; 2079 *pc = ucontext->uc_mcontext.mc_eip; 2080 *bp = ucontext->uc_mcontext.mc_ebp; 2081 *sp = ucontext->uc_mcontext.mc_esp; 2082 # else 2083 ucontext_t *ucontext = (ucontext_t*)context; 2084 # if SANITIZER_SOLARIS 2085 /* Use the numeric values: the symbolic ones are undefined by llvm 2086 include/llvm/Support/Solaris.h. */ 2087 # ifndef REG_EIP 2088 # define REG_EIP 14 // REG_PC 2089 # endif 2090 # ifndef REG_EBP 2091 # define REG_EBP 6 // REG_FP 2092 # endif 2093 # ifndef REG_UESP 2094 # define REG_UESP 17 // REG_SP 2095 # endif 2096 # endif 2097 *pc = ucontext->uc_mcontext.gregs[REG_EIP]; 2098 *bp = ucontext->uc_mcontext.gregs[REG_EBP]; 2099 *sp = ucontext->uc_mcontext.gregs[REG_UESP]; 2100 # endif 2101 #elif defined(__powerpc__) || defined(__powerpc64__) 2102 # if SANITIZER_FREEBSD 2103 ucontext_t *ucontext = (ucontext_t *)context; 2104 *pc = ucontext->uc_mcontext.mc_srr0; 2105 *sp = ucontext->uc_mcontext.mc_frame[1]; 2106 *bp = ucontext->uc_mcontext.mc_frame[31]; 2107 # else 2108 ucontext_t *ucontext = (ucontext_t*)context; 2109 *pc = ucontext->uc_mcontext.regs->nip; 2110 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1]; 2111 // The powerpc{,64}-linux ABIs do not specify r31 as the frame 2112 // pointer, but GCC always uses r31 when we need a frame pointer. 2113 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31]; 2114 # endif 2115 #elif defined(__sparc__) 2116 #if defined(__arch64__) || defined(__sparcv9) 2117 #define STACK_BIAS 2047 2118 #else 2119 #define STACK_BIAS 0 2120 # endif 2121 # if SANITIZER_SOLARIS 2122 ucontext_t *ucontext = (ucontext_t *)context; 2123 *pc = ucontext->uc_mcontext.gregs[REG_PC]; 2124 *sp = ucontext->uc_mcontext.gregs[REG_O6] + STACK_BIAS; 2125 #else 2126 // Historical BSDism here. 2127 struct sigcontext *scontext = (struct sigcontext *)context; 2128 #if defined(__arch64__) 2129 *pc = scontext->sigc_regs.tpc; 2130 *sp = scontext->sigc_regs.u_regs[14] + STACK_BIAS; 2131 #else 2132 *pc = scontext->si_regs.pc; 2133 *sp = scontext->si_regs.u_regs[14]; 2134 #endif 2135 # endif 2136 *bp = (uptr)((uhwptr *)*sp)[14] + STACK_BIAS; 2137 #elif defined(__mips__) 2138 ucontext_t *ucontext = (ucontext_t*)context; 2139 *pc = ucontext->uc_mcontext.pc; 2140 *bp = ucontext->uc_mcontext.gregs[30]; 2141 *sp = ucontext->uc_mcontext.gregs[29]; 2142 #elif defined(__s390__) 2143 ucontext_t *ucontext = (ucontext_t*)context; 2144 # if defined(__s390x__) 2145 *pc = ucontext->uc_mcontext.psw.addr; 2146 # else 2147 *pc = ucontext->uc_mcontext.psw.addr & 0x7fffffff; 2148 # endif 2149 *bp = ucontext->uc_mcontext.gregs[11]; 2150 *sp = ucontext->uc_mcontext.gregs[15]; 2151 #elif defined(__riscv) 2152 ucontext_t *ucontext = (ucontext_t*)context; 2153 # if SANITIZER_FREEBSD 2154 *pc = ucontext->uc_mcontext.mc_gpregs.gp_sepc; 2155 *bp = ucontext->uc_mcontext.mc_gpregs.gp_s[0]; 2156 *sp = ucontext->uc_mcontext.mc_gpregs.gp_sp; 2157 # else 2158 *pc = ucontext->uc_mcontext.__gregs[REG_PC]; 2159 *bp = ucontext->uc_mcontext.__gregs[REG_S0]; 2160 *sp = ucontext->uc_mcontext.__gregs[REG_SP]; 2161 # endif 2162 # elif defined(__hexagon__) 2163 ucontext_t *ucontext = (ucontext_t *)context; 2164 *pc = ucontext->uc_mcontext.pc; 2165 *bp = ucontext->uc_mcontext.r30; 2166 *sp = ucontext->uc_mcontext.r29; 2167 # else 2168 # error "Unsupported arch" 2169 # endif 2170 } 2171 2172 void SignalContext::InitPcSpBp() { GetPcSpBp(context, &pc, &sp, &bp); } 2173 2174 void InitializePlatformEarly() { 2175 // Do nothing. 2176 } 2177 2178 void MaybeReexec() { 2179 // No need to re-exec on Linux. 2180 } 2181 2182 void CheckASLR() { 2183 #if SANITIZER_NETBSD 2184 int mib[3]; 2185 int paxflags; 2186 uptr len = sizeof(paxflags); 2187 2188 mib[0] = CTL_PROC; 2189 mib[1] = internal_getpid(); 2190 mib[2] = PROC_PID_PAXFLAGS; 2191 2192 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2193 Printf("sysctl failed\n"); 2194 Die(); 2195 } 2196 2197 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_ASLR)) { 2198 Printf("This sanitizer is not compatible with enabled ASLR.\n" 2199 "To disable ASLR, please run \"paxctl +a %s\" and try again.\n", 2200 GetArgv()[0]); 2201 Die(); 2202 } 2203 #elif SANITIZER_FREEBSD 2204 int aslr_status; 2205 int r = internal_procctl(P_PID, 0, PROC_ASLR_STATUS, &aslr_status); 2206 if (UNLIKELY(r == -1)) { 2207 // We're making things less 'dramatic' here since 2208 // the cmd is not necessarily guaranteed to be here 2209 // just yet regarding FreeBSD release 2210 return; 2211 } 2212 if ((aslr_status & PROC_ASLR_ACTIVE) != 0) { 2213 Printf("This sanitizer is not compatible with enabled ASLR " 2214 "and binaries compiled with PIE\n"); 2215 Die(); 2216 } 2217 # elif SANITIZER_PPC64V2 2218 // Disable ASLR for Linux PPC64LE. 2219 int old_personality = personality(0xffffffff); 2220 if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) { 2221 VReport(1, 2222 "WARNING: Program is being run with address space layout " 2223 "randomization (ASLR) enabled which prevents the thread and " 2224 "memory sanitizers from working on powerpc64le.\n" 2225 "ASLR will be disabled and the program re-executed.\n"); 2226 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1); 2227 ReExec(); 2228 } 2229 # else 2230 // Do nothing 2231 # endif 2232 } 2233 2234 void CheckMPROTECT() { 2235 #if SANITIZER_NETBSD 2236 int mib[3]; 2237 int paxflags; 2238 uptr len = sizeof(paxflags); 2239 2240 mib[0] = CTL_PROC; 2241 mib[1] = internal_getpid(); 2242 mib[2] = PROC_PID_PAXFLAGS; 2243 2244 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2245 Printf("sysctl failed\n"); 2246 Die(); 2247 } 2248 2249 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_MPROTECT)) { 2250 Printf("This sanitizer is not compatible with enabled MPROTECT\n"); 2251 Die(); 2252 } 2253 #else 2254 // Do nothing 2255 #endif 2256 } 2257 2258 void CheckNoDeepBind(const char *filename, int flag) { 2259 #ifdef RTLD_DEEPBIND 2260 if (flag & RTLD_DEEPBIND) { 2261 Report( 2262 "You are trying to dlopen a %s shared library with RTLD_DEEPBIND flag" 2263 " which is incompatible with sanitizer runtime " 2264 "(see https://github.com/google/sanitizers/issues/611 for details" 2265 "). If you want to run %s library under sanitizers please remove " 2266 "RTLD_DEEPBIND from dlopen flags.\n", 2267 filename, filename); 2268 Die(); 2269 } 2270 #endif 2271 } 2272 2273 uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding, 2274 uptr *largest_gap_found, 2275 uptr *max_occupied_addr) { 2276 UNREACHABLE("FindAvailableMemoryRange is not available"); 2277 return 0; 2278 } 2279 2280 bool GetRandom(void *buffer, uptr length, bool blocking) { 2281 if (!buffer || !length || length > 256) 2282 return false; 2283 #if SANITIZER_USE_GETENTROPY 2284 uptr rnd = getentropy(buffer, length); 2285 int rverrno = 0; 2286 if (internal_iserror(rnd, &rverrno) && rverrno == EFAULT) 2287 return false; 2288 else if (rnd == 0) 2289 return true; 2290 #endif // SANITIZER_USE_GETENTROPY 2291 2292 #if SANITIZER_USE_GETRANDOM 2293 static atomic_uint8_t skip_getrandom_syscall; 2294 if (!atomic_load_relaxed(&skip_getrandom_syscall)) { 2295 // Up to 256 bytes, getrandom will not be interrupted. 2296 uptr res = internal_syscall(SYSCALL(getrandom), buffer, length, 2297 blocking ? 0 : GRND_NONBLOCK); 2298 int rverrno = 0; 2299 if (internal_iserror(res, &rverrno) && rverrno == ENOSYS) 2300 atomic_store_relaxed(&skip_getrandom_syscall, 1); 2301 else if (res == length) 2302 return true; 2303 } 2304 #endif // SANITIZER_USE_GETRANDOM 2305 // Up to 256 bytes, a read off /dev/urandom will not be interrupted. 2306 // blocking is moot here, O_NONBLOCK has no effect when opening /dev/urandom. 2307 uptr fd = internal_open("/dev/urandom", O_RDONLY); 2308 if (internal_iserror(fd)) 2309 return false; 2310 uptr res = internal_read(fd, buffer, length); 2311 if (internal_iserror(res)) 2312 return false; 2313 internal_close(fd); 2314 return true; 2315 } 2316 2317 } // namespace __sanitizer 2318 2319 #endif 2320