1 //===-- sanitizer_linux.cpp -----------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file is shared between AddressSanitizer and ThreadSanitizer 10 // run-time libraries and implements linux-specific functions from 11 // sanitizer_libc.h. 12 //===----------------------------------------------------------------------===// 13 14 #include "sanitizer_platform.h" 15 16 #if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \ 17 SANITIZER_SOLARIS 18 19 #include "sanitizer_common.h" 20 #include "sanitizer_flags.h" 21 #include "sanitizer_getauxval.h" 22 #include "sanitizer_internal_defs.h" 23 #include "sanitizer_libc.h" 24 #include "sanitizer_linux.h" 25 #include "sanitizer_mutex.h" 26 #include "sanitizer_placement_new.h" 27 #include "sanitizer_procmaps.h" 28 29 #if SANITIZER_LINUX && !SANITIZER_GO 30 #include <asm/param.h> 31 #endif 32 33 // For mips64, syscall(__NR_stat) fills the buffer in the 'struct kernel_stat' 34 // format. Struct kernel_stat is defined as 'struct stat' in asm/stat.h. To 35 // access stat from asm/stat.h, without conflicting with definition in 36 // sys/stat.h, we use this trick. 37 #if defined(__mips64) 38 #include <asm/unistd.h> 39 #include <sys/types.h> 40 #define stat kernel_stat 41 #if SANITIZER_GO 42 #undef st_atime 43 #undef st_mtime 44 #undef st_ctime 45 #define st_atime st_atim 46 #define st_mtime st_mtim 47 #define st_ctime st_ctim 48 #endif 49 #include <asm/stat.h> 50 #undef stat 51 #endif 52 53 #include <dlfcn.h> 54 #include <errno.h> 55 #include <fcntl.h> 56 #include <link.h> 57 #include <pthread.h> 58 #include <sched.h> 59 #include <signal.h> 60 #include <sys/mman.h> 61 #include <sys/param.h> 62 #if !SANITIZER_SOLARIS 63 #include <sys/ptrace.h> 64 #endif 65 #include <sys/resource.h> 66 #include <sys/stat.h> 67 #include <sys/syscall.h> 68 #include <sys/time.h> 69 #include <sys/types.h> 70 #include <ucontext.h> 71 #include <unistd.h> 72 73 #if SANITIZER_LINUX 74 #include <sys/utsname.h> 75 #endif 76 77 #if SANITIZER_LINUX && !SANITIZER_ANDROID 78 #include <sys/personality.h> 79 #endif 80 81 #if SANITIZER_FREEBSD 82 #include <sys/exec.h> 83 #include <sys/sysctl.h> 84 #include <machine/atomic.h> 85 extern "C" { 86 // <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on 87 // FreeBSD 9.2 and 10.0. 88 #include <sys/umtx.h> 89 } 90 #include <sys/thr.h> 91 #endif // SANITIZER_FREEBSD 92 93 #if SANITIZER_NETBSD 94 #include <limits.h> // For NAME_MAX 95 #include <sys/sysctl.h> 96 #include <sys/exec.h> 97 extern struct ps_strings *__ps_strings; 98 #endif // SANITIZER_NETBSD 99 100 #if SANITIZER_SOLARIS 101 #include <stdlib.h> 102 #include <thread.h> 103 #define environ _environ 104 #endif 105 106 extern char **environ; 107 108 #if SANITIZER_LINUX 109 // <linux/time.h> 110 struct kernel_timeval { 111 long tv_sec; 112 long tv_usec; 113 }; 114 115 // <linux/futex.h> is broken on some linux distributions. 116 const int FUTEX_WAIT = 0; 117 const int FUTEX_WAKE = 1; 118 const int FUTEX_PRIVATE_FLAG = 128; 119 const int FUTEX_WAIT_PRIVATE = FUTEX_WAIT | FUTEX_PRIVATE_FLAG; 120 const int FUTEX_WAKE_PRIVATE = FUTEX_WAKE | FUTEX_PRIVATE_FLAG; 121 #endif // SANITIZER_LINUX 122 123 // Are we using 32-bit or 64-bit Linux syscalls? 124 // x32 (which defines __x86_64__) has SANITIZER_WORDSIZE == 32 125 // but it still needs to use 64-bit syscalls. 126 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__powerpc64__) || \ 127 SANITIZER_WORDSIZE == 64) 128 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 1 129 #else 130 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 0 131 #endif 132 133 // Note : FreeBSD had implemented both 134 // Linux apis, available from 135 // future 12.x version most likely 136 #if SANITIZER_LINUX && defined(__NR_getrandom) 137 # if !defined(GRND_NONBLOCK) 138 # define GRND_NONBLOCK 1 139 # endif 140 # define SANITIZER_USE_GETRANDOM 1 141 #else 142 # define SANITIZER_USE_GETRANDOM 0 143 #endif // SANITIZER_LINUX && defined(__NR_getrandom) 144 145 #if SANITIZER_FREEBSD && __FreeBSD_version >= 1200000 146 # define SANITIZER_USE_GETENTROPY 1 147 #else 148 # define SANITIZER_USE_GETENTROPY 0 149 #endif 150 151 namespace __sanitizer { 152 153 #if SANITIZER_LINUX && defined(__x86_64__) 154 #include "sanitizer_syscall_linux_x86_64.inc" 155 #elif SANITIZER_LINUX && SANITIZER_RISCV64 156 #include "sanitizer_syscall_linux_riscv64.inc" 157 #elif SANITIZER_LINUX && defined(__aarch64__) 158 #include "sanitizer_syscall_linux_aarch64.inc" 159 #elif SANITIZER_LINUX && defined(__arm__) 160 #include "sanitizer_syscall_linux_arm.inc" 161 #else 162 #include "sanitizer_syscall_generic.inc" 163 #endif 164 165 // --------------- sanitizer_libc.h 166 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 167 #if !SANITIZER_S390 168 uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd, 169 u64 offset) { 170 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 171 return internal_syscall(SYSCALL(mmap), (uptr)addr, length, prot, flags, fd, 172 offset); 173 #else 174 // mmap2 specifies file offset in 4096-byte units. 175 CHECK(IsAligned(offset, 4096)); 176 return internal_syscall(SYSCALL(mmap2), addr, length, prot, flags, fd, 177 offset / 4096); 178 #endif 179 } 180 #endif // !SANITIZER_S390 181 182 uptr internal_munmap(void *addr, uptr length) { 183 return internal_syscall(SYSCALL(munmap), (uptr)addr, length); 184 } 185 186 int internal_mprotect(void *addr, uptr length, int prot) { 187 return internal_syscall(SYSCALL(mprotect), (uptr)addr, length, prot); 188 } 189 190 int internal_madvise(uptr addr, uptr length, int advice) { 191 return internal_syscall(SYSCALL(madvise), addr, length, advice); 192 } 193 194 uptr internal_close(fd_t fd) { 195 return internal_syscall(SYSCALL(close), fd); 196 } 197 198 uptr internal_open(const char *filename, int flags) { 199 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 200 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags); 201 #else 202 return internal_syscall(SYSCALL(open), (uptr)filename, flags); 203 #endif 204 } 205 206 uptr internal_open(const char *filename, int flags, u32 mode) { 207 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 208 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags, 209 mode); 210 #else 211 return internal_syscall(SYSCALL(open), (uptr)filename, flags, mode); 212 #endif 213 } 214 215 uptr internal_read(fd_t fd, void *buf, uptr count) { 216 sptr res; 217 HANDLE_EINTR(res, 218 (sptr)internal_syscall(SYSCALL(read), fd, (uptr)buf, count)); 219 return res; 220 } 221 222 uptr internal_write(fd_t fd, const void *buf, uptr count) { 223 sptr res; 224 HANDLE_EINTR(res, 225 (sptr)internal_syscall(SYSCALL(write), fd, (uptr)buf, count)); 226 return res; 227 } 228 229 uptr internal_ftruncate(fd_t fd, uptr size) { 230 sptr res; 231 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(ftruncate), fd, 232 (OFF_T)size)); 233 return res; 234 } 235 236 #if !SANITIZER_LINUX_USES_64BIT_SYSCALLS && SANITIZER_LINUX 237 static void stat64_to_stat(struct stat64 *in, struct stat *out) { 238 internal_memset(out, 0, sizeof(*out)); 239 out->st_dev = in->st_dev; 240 out->st_ino = in->st_ino; 241 out->st_mode = in->st_mode; 242 out->st_nlink = in->st_nlink; 243 out->st_uid = in->st_uid; 244 out->st_gid = in->st_gid; 245 out->st_rdev = in->st_rdev; 246 out->st_size = in->st_size; 247 out->st_blksize = in->st_blksize; 248 out->st_blocks = in->st_blocks; 249 out->st_atime = in->st_atime; 250 out->st_mtime = in->st_mtime; 251 out->st_ctime = in->st_ctime; 252 } 253 #endif 254 255 #if defined(__mips64) 256 // Undefine compatibility macros from <sys/stat.h> 257 // so that they would not clash with the kernel_stat 258 // st_[a|m|c]time fields 259 #if !SANITIZER_GO 260 #undef st_atime 261 #undef st_mtime 262 #undef st_ctime 263 #endif 264 #if defined(SANITIZER_ANDROID) 265 // Bionic sys/stat.h defines additional macros 266 // for compatibility with the old NDKs and 267 // they clash with the kernel_stat structure 268 // st_[a|m|c]time_nsec fields. 269 #undef st_atime_nsec 270 #undef st_mtime_nsec 271 #undef st_ctime_nsec 272 #endif 273 static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) { 274 internal_memset(out, 0, sizeof(*out)); 275 out->st_dev = in->st_dev; 276 out->st_ino = in->st_ino; 277 out->st_mode = in->st_mode; 278 out->st_nlink = in->st_nlink; 279 out->st_uid = in->st_uid; 280 out->st_gid = in->st_gid; 281 out->st_rdev = in->st_rdev; 282 out->st_size = in->st_size; 283 out->st_blksize = in->st_blksize; 284 out->st_blocks = in->st_blocks; 285 #if defined(__USE_MISC) || \ 286 defined(__USE_XOPEN2K8) || \ 287 defined(SANITIZER_ANDROID) 288 out->st_atim.tv_sec = in->st_atime; 289 out->st_atim.tv_nsec = in->st_atime_nsec; 290 out->st_mtim.tv_sec = in->st_mtime; 291 out->st_mtim.tv_nsec = in->st_mtime_nsec; 292 out->st_ctim.tv_sec = in->st_ctime; 293 out->st_ctim.tv_nsec = in->st_ctime_nsec; 294 #else 295 out->st_atime = in->st_atime; 296 out->st_atimensec = in->st_atime_nsec; 297 out->st_mtime = in->st_mtime; 298 out->st_mtimensec = in->st_mtime_nsec; 299 out->st_ctime = in->st_ctime; 300 out->st_atimensec = in->st_ctime_nsec; 301 #endif 302 } 303 #endif 304 305 uptr internal_stat(const char *path, void *buf) { 306 #if SANITIZER_FREEBSD 307 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 0); 308 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 309 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 310 0); 311 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 312 # if defined(__mips64) 313 // For mips64, stat syscall fills buffer in the format of kernel_stat 314 struct kernel_stat kbuf; 315 int res = internal_syscall(SYSCALL(stat), path, &kbuf); 316 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 317 return res; 318 # else 319 return internal_syscall(SYSCALL(stat), (uptr)path, (uptr)buf); 320 # endif 321 #else 322 struct stat64 buf64; 323 int res = internal_syscall(SYSCALL(stat64), path, &buf64); 324 stat64_to_stat(&buf64, (struct stat *)buf); 325 return res; 326 #endif 327 } 328 329 uptr internal_lstat(const char *path, void *buf) { 330 #if SANITIZER_FREEBSD 331 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 332 AT_SYMLINK_NOFOLLOW); 333 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 334 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 335 AT_SYMLINK_NOFOLLOW); 336 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 337 # if SANITIZER_MIPS64 338 // For mips64, lstat syscall fills buffer in the format of kernel_stat 339 struct kernel_stat kbuf; 340 int res = internal_syscall(SYSCALL(lstat), path, &kbuf); 341 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 342 return res; 343 # else 344 return internal_syscall(SYSCALL(lstat), (uptr)path, (uptr)buf); 345 # endif 346 #else 347 struct stat64 buf64; 348 int res = internal_syscall(SYSCALL(lstat64), path, &buf64); 349 stat64_to_stat(&buf64, (struct stat *)buf); 350 return res; 351 #endif 352 } 353 354 uptr internal_fstat(fd_t fd, void *buf) { 355 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 356 #if SANITIZER_MIPS64 357 // For mips64, fstat syscall fills buffer in the format of kernel_stat 358 struct kernel_stat kbuf; 359 int res = internal_syscall(SYSCALL(fstat), fd, &kbuf); 360 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 361 return res; 362 # else 363 return internal_syscall(SYSCALL(fstat), fd, (uptr)buf); 364 # endif 365 #else 366 struct stat64 buf64; 367 int res = internal_syscall(SYSCALL(fstat64), fd, &buf64); 368 stat64_to_stat(&buf64, (struct stat *)buf); 369 return res; 370 #endif 371 } 372 373 uptr internal_filesize(fd_t fd) { 374 struct stat st; 375 if (internal_fstat(fd, &st)) 376 return -1; 377 return (uptr)st.st_size; 378 } 379 380 uptr internal_dup(int oldfd) { 381 return internal_syscall(SYSCALL(dup), oldfd); 382 } 383 384 uptr internal_dup2(int oldfd, int newfd) { 385 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 386 return internal_syscall(SYSCALL(dup3), oldfd, newfd, 0); 387 #else 388 return internal_syscall(SYSCALL(dup2), oldfd, newfd); 389 #endif 390 } 391 392 uptr internal_readlink(const char *path, char *buf, uptr bufsize) { 393 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 394 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD, (uptr)path, (uptr)buf, 395 bufsize); 396 #else 397 return internal_syscall(SYSCALL(readlink), (uptr)path, (uptr)buf, bufsize); 398 #endif 399 } 400 401 uptr internal_unlink(const char *path) { 402 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 403 return internal_syscall(SYSCALL(unlinkat), AT_FDCWD, (uptr)path, 0); 404 #else 405 return internal_syscall(SYSCALL(unlink), (uptr)path); 406 #endif 407 } 408 409 uptr internal_rename(const char *oldpath, const char *newpath) { 410 #if defined(__riscv) 411 return internal_syscall(SYSCALL(renameat2), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 412 (uptr)newpath, 0); 413 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 414 return internal_syscall(SYSCALL(renameat), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 415 (uptr)newpath); 416 #else 417 return internal_syscall(SYSCALL(rename), (uptr)oldpath, (uptr)newpath); 418 #endif 419 } 420 421 uptr internal_sched_yield() { 422 return internal_syscall(SYSCALL(sched_yield)); 423 } 424 425 unsigned int internal_sleep(unsigned int seconds) { 426 struct timespec ts; 427 ts.tv_sec = seconds; 428 ts.tv_nsec = 0; 429 int res = internal_syscall(SYSCALL(nanosleep), &ts, &ts); 430 if (res) return ts.tv_sec; 431 return 0; 432 } 433 434 uptr internal_execve(const char *filename, char *const argv[], 435 char *const envp[]) { 436 return internal_syscall(SYSCALL(execve), (uptr)filename, (uptr)argv, 437 (uptr)envp); 438 } 439 #endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD 440 441 #if !SANITIZER_NETBSD 442 void internal__exit(int exitcode) { 443 #if SANITIZER_FREEBSD || SANITIZER_SOLARIS 444 internal_syscall(SYSCALL(exit), exitcode); 445 #else 446 internal_syscall(SYSCALL(exit_group), exitcode); 447 #endif 448 Die(); // Unreachable. 449 } 450 #endif // !SANITIZER_NETBSD 451 452 // ----------------- sanitizer_common.h 453 bool FileExists(const char *filename) { 454 if (ShouldMockFailureToOpen(filename)) 455 return false; 456 struct stat st; 457 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 458 if (internal_syscall(SYSCALL(newfstatat), AT_FDCWD, filename, &st, 0)) 459 #else 460 if (internal_stat(filename, &st)) 461 #endif 462 return false; 463 // Sanity check: filename is a regular file. 464 return S_ISREG(st.st_mode); 465 } 466 467 #if !SANITIZER_NETBSD 468 tid_t GetTid() { 469 #if SANITIZER_FREEBSD 470 long Tid; 471 thr_self(&Tid); 472 return Tid; 473 #elif SANITIZER_SOLARIS 474 return thr_self(); 475 #else 476 return internal_syscall(SYSCALL(gettid)); 477 #endif 478 } 479 480 int TgKill(pid_t pid, tid_t tid, int sig) { 481 #if SANITIZER_LINUX 482 return internal_syscall(SYSCALL(tgkill), pid, tid, sig); 483 #elif SANITIZER_FREEBSD 484 return internal_syscall(SYSCALL(thr_kill2), pid, tid, sig); 485 #elif SANITIZER_SOLARIS 486 (void)pid; 487 return thr_kill(tid, sig); 488 #endif 489 } 490 #endif 491 492 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 493 u64 NanoTime() { 494 #if SANITIZER_FREEBSD 495 timeval tv; 496 #else 497 kernel_timeval tv; 498 #endif 499 internal_memset(&tv, 0, sizeof(tv)); 500 internal_syscall(SYSCALL(gettimeofday), &tv, 0); 501 return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000; 502 } 503 504 uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) { 505 return internal_syscall(SYSCALL(clock_gettime), clk_id, tp); 506 } 507 #endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD 508 509 // Like getenv, but reads env directly from /proc (on Linux) or parses the 510 // 'environ' array (on some others) and does not use libc. This function 511 // should be called first inside __asan_init. 512 const char *GetEnv(const char *name) { 513 #if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_SOLARIS 514 if (::environ != 0) { 515 uptr NameLen = internal_strlen(name); 516 for (char **Env = ::environ; *Env != 0; Env++) { 517 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=') 518 return (*Env) + NameLen + 1; 519 } 520 } 521 return 0; // Not found. 522 #elif SANITIZER_LINUX 523 static char *environ; 524 static uptr len; 525 static bool inited; 526 if (!inited) { 527 inited = true; 528 uptr environ_size; 529 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len)) 530 environ = nullptr; 531 } 532 if (!environ || len == 0) return nullptr; 533 uptr namelen = internal_strlen(name); 534 const char *p = environ; 535 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer 536 // proc file has the format NAME=value\0NAME=value\0NAME=value\0... 537 const char* endp = 538 (char*)internal_memchr(p, '\0', len - (p - environ)); 539 if (!endp) // this entry isn't NUL terminated 540 return nullptr; 541 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match. 542 return p + namelen + 1; // point after = 543 p = endp + 1; 544 } 545 return nullptr; // Not found. 546 #else 547 #error "Unsupported platform" 548 #endif 549 } 550 551 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD && !SANITIZER_GO 552 extern "C" { 553 SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end; 554 } 555 #endif 556 557 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD 558 static void ReadNullSepFileToArray(const char *path, char ***arr, 559 int arr_size) { 560 char *buff; 561 uptr buff_size; 562 uptr buff_len; 563 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray"); 564 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) { 565 (*arr)[0] = nullptr; 566 return; 567 } 568 (*arr)[0] = buff; 569 int count, i; 570 for (count = 1, i = 1; ; i++) { 571 if (buff[i] == 0) { 572 if (buff[i+1] == 0) break; 573 (*arr)[count] = &buff[i+1]; 574 CHECK_LE(count, arr_size - 1); // FIXME: make this more flexible. 575 count++; 576 } 577 } 578 (*arr)[count] = nullptr; 579 } 580 #endif 581 582 static void GetArgsAndEnv(char ***argv, char ***envp) { 583 #if SANITIZER_FREEBSD 584 // On FreeBSD, retrieving the argument and environment arrays is done via the 585 // kern.ps_strings sysctl, which returns a pointer to a structure containing 586 // this information. See also <sys/exec.h>. 587 ps_strings *pss; 588 uptr sz = sizeof(pss); 589 if (internal_sysctlbyname("kern.ps_strings", &pss, &sz, NULL, 0) == -1) { 590 Printf("sysctl kern.ps_strings failed\n"); 591 Die(); 592 } 593 *argv = pss->ps_argvstr; 594 *envp = pss->ps_envstr; 595 #elif SANITIZER_NETBSD 596 *argv = __ps_strings->ps_argvstr; 597 *envp = __ps_strings->ps_envstr; 598 #else // SANITIZER_FREEBSD 599 #if !SANITIZER_GO 600 if (&__libc_stack_end) { 601 uptr* stack_end = (uptr*)__libc_stack_end; 602 // Normally argc can be obtained from *stack_end, however, on ARM glibc's 603 // _start clobbers it: 604 // https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/arm/start.S;hb=refs/heads/release/2.31/master#l75 605 // Do not special-case ARM and infer argc from argv everywhere. 606 int argc = 0; 607 while (stack_end[argc + 1]) argc++; 608 *argv = (char**)(stack_end + 1); 609 *envp = (char**)(stack_end + argc + 2); 610 } else { 611 #endif // !SANITIZER_GO 612 static const int kMaxArgv = 2000, kMaxEnvp = 2000; 613 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv); 614 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp); 615 #if !SANITIZER_GO 616 } 617 #endif // !SANITIZER_GO 618 #endif // SANITIZER_FREEBSD 619 } 620 621 char **GetArgv() { 622 char **argv, **envp; 623 GetArgsAndEnv(&argv, &envp); 624 return argv; 625 } 626 627 char **GetEnviron() { 628 char **argv, **envp; 629 GetArgsAndEnv(&argv, &envp); 630 return envp; 631 } 632 633 #if !SANITIZER_SOLARIS 634 enum MutexState { 635 MtxUnlocked = 0, 636 MtxLocked = 1, 637 MtxSleeping = 2 638 }; 639 640 BlockingMutex::BlockingMutex() { 641 internal_memset(this, 0, sizeof(*this)); 642 } 643 644 void BlockingMutex::Lock() { 645 CHECK_EQ(owner_, 0); 646 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 647 if (atomic_exchange(m, MtxLocked, memory_order_acquire) == MtxUnlocked) 648 return; 649 while (atomic_exchange(m, MtxSleeping, memory_order_acquire) != MtxUnlocked) { 650 #if SANITIZER_FREEBSD 651 _umtx_op(m, UMTX_OP_WAIT_UINT, MtxSleeping, 0, 0); 652 #elif SANITIZER_NETBSD 653 sched_yield(); /* No userspace futex-like synchronization */ 654 #else 655 internal_syscall(SYSCALL(futex), (uptr)m, FUTEX_WAIT_PRIVATE, MtxSleeping, 656 0, 0, 0); 657 #endif 658 } 659 } 660 661 void BlockingMutex::Unlock() { 662 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 663 u32 v = atomic_exchange(m, MtxUnlocked, memory_order_release); 664 CHECK_NE(v, MtxUnlocked); 665 if (v == MtxSleeping) { 666 #if SANITIZER_FREEBSD 667 _umtx_op(m, UMTX_OP_WAKE, 1, 0, 0); 668 #elif SANITIZER_NETBSD 669 /* No userspace futex-like synchronization */ 670 #else 671 internal_syscall(SYSCALL(futex), (uptr)m, FUTEX_WAKE_PRIVATE, 1, 0, 0, 0); 672 #endif 673 } 674 } 675 676 void BlockingMutex::CheckLocked() { 677 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 678 CHECK_NE(MtxUnlocked, atomic_load(m, memory_order_relaxed)); 679 } 680 #endif // !SANITIZER_SOLARIS 681 682 // ----------------- sanitizer_linux.h 683 // The actual size of this structure is specified by d_reclen. 684 // Note that getdents64 uses a different structure format. We only provide the 685 // 32-bit syscall here. 686 #if SANITIZER_NETBSD 687 // Not used 688 #else 689 struct linux_dirent { 690 #if SANITIZER_X32 || defined(__aarch64__) || SANITIZER_RISCV64 691 u64 d_ino; 692 u64 d_off; 693 #else 694 unsigned long d_ino; 695 unsigned long d_off; 696 #endif 697 unsigned short d_reclen; 698 #if defined(__aarch64__) || SANITIZER_RISCV64 699 unsigned char d_type; 700 #endif 701 char d_name[256]; 702 }; 703 #endif 704 705 #if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 706 // Syscall wrappers. 707 uptr internal_ptrace(int request, int pid, void *addr, void *data) { 708 return internal_syscall(SYSCALL(ptrace), request, pid, (uptr)addr, 709 (uptr)data); 710 } 711 712 uptr internal_waitpid(int pid, int *status, int options) { 713 return internal_syscall(SYSCALL(wait4), pid, (uptr)status, options, 714 0 /* rusage */); 715 } 716 717 uptr internal_getpid() { 718 return internal_syscall(SYSCALL(getpid)); 719 } 720 721 uptr internal_getppid() { 722 return internal_syscall(SYSCALL(getppid)); 723 } 724 725 int internal_dlinfo(void *handle, int request, void *p) { 726 #if SANITIZER_FREEBSD 727 return dlinfo(handle, request, p); 728 #else 729 UNIMPLEMENTED(); 730 #endif 731 } 732 733 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) { 734 #if SANITIZER_FREEBSD 735 return internal_syscall(SYSCALL(getdirentries), fd, (uptr)dirp, count, NULL); 736 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 737 return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count); 738 #else 739 return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count); 740 #endif 741 } 742 743 uptr internal_lseek(fd_t fd, OFF_T offset, int whence) { 744 return internal_syscall(SYSCALL(lseek), fd, offset, whence); 745 } 746 747 #if SANITIZER_LINUX 748 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) { 749 return internal_syscall(SYSCALL(prctl), option, arg2, arg3, arg4, arg5); 750 } 751 #endif 752 753 uptr internal_sigaltstack(const void *ss, void *oss) { 754 return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss); 755 } 756 757 int internal_fork() { 758 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 759 return internal_syscall(SYSCALL(clone), SIGCHLD, 0); 760 #else 761 return internal_syscall(SYSCALL(fork)); 762 #endif 763 } 764 765 #if SANITIZER_FREEBSD 766 int internal_sysctl(const int *name, unsigned int namelen, void *oldp, 767 uptr *oldlenp, const void *newp, uptr newlen) { 768 return internal_syscall(SYSCALL(__sysctl), name, namelen, oldp, 769 (size_t *)oldlenp, newp, (size_t)newlen); 770 } 771 772 int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp, 773 const void *newp, uptr newlen) { 774 // Note: this function can be called during startup, so we need to avoid 775 // calling any interceptable functions. On FreeBSD >= 1300045 sysctlbyname() 776 // is a real syscall, but for older versions it calls sysctlnametomib() 777 // followed by sysctl(). To avoid calling the intercepted version and 778 // asserting if this happens during startup, call the real sysctlnametomib() 779 // followed by internal_sysctl() if the syscall is not available. 780 #ifdef SYS___sysctlbyname 781 return internal_syscall(SYSCALL(__sysctlbyname), sname, 782 internal_strlen(sname), oldp, (size_t *)oldlenp, newp, 783 (size_t)newlen); 784 #else 785 static decltype(sysctlnametomib) *real_sysctlnametomib = nullptr; 786 if (!real_sysctlnametomib) 787 real_sysctlnametomib = 788 (decltype(sysctlnametomib) *)dlsym(RTLD_NEXT, "sysctlnametomib"); 789 CHECK(real_sysctlnametomib); 790 791 int oid[CTL_MAXNAME]; 792 size_t len = CTL_MAXNAME; 793 if (real_sysctlnametomib(sname, oid, &len) == -1) 794 return (-1); 795 return internal_sysctl(oid, len, oldp, oldlenp, newp, newlen); 796 #endif 797 } 798 #endif 799 800 #if SANITIZER_LINUX 801 #define SA_RESTORER 0x04000000 802 // Doesn't set sa_restorer if the caller did not set it, so use with caution 803 //(see below). 804 int internal_sigaction_norestorer(int signum, const void *act, void *oldact) { 805 __sanitizer_kernel_sigaction_t k_act, k_oldact; 806 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t)); 807 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t)); 808 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act; 809 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact; 810 if (u_act) { 811 k_act.handler = u_act->handler; 812 k_act.sigaction = u_act->sigaction; 813 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask, 814 sizeof(__sanitizer_kernel_sigset_t)); 815 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL). 816 k_act.sa_flags = u_act->sa_flags | SA_RESTORER; 817 // FIXME: most often sa_restorer is unset, however the kernel requires it 818 // to point to a valid signal restorer that calls the rt_sigreturn syscall. 819 // If sa_restorer passed to the kernel is NULL, the program may crash upon 820 // signal delivery or fail to unwind the stack in the signal handler. 821 // libc implementation of sigaction() passes its own restorer to 822 // rt_sigaction, so we need to do the same (we'll need to reimplement the 823 // restorers; for x86_64 the restorer address can be obtained from 824 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact). 825 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 826 k_act.sa_restorer = u_act->sa_restorer; 827 #endif 828 } 829 830 uptr result = internal_syscall(SYSCALL(rt_sigaction), (uptr)signum, 831 (uptr)(u_act ? &k_act : nullptr), 832 (uptr)(u_oldact ? &k_oldact : nullptr), 833 (uptr)sizeof(__sanitizer_kernel_sigset_t)); 834 835 if ((result == 0) && u_oldact) { 836 u_oldact->handler = k_oldact.handler; 837 u_oldact->sigaction = k_oldact.sigaction; 838 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask, 839 sizeof(__sanitizer_kernel_sigset_t)); 840 u_oldact->sa_flags = k_oldact.sa_flags; 841 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 842 u_oldact->sa_restorer = k_oldact.sa_restorer; 843 #endif 844 } 845 return result; 846 } 847 #endif // SANITIZER_LINUX 848 849 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set, 850 __sanitizer_sigset_t *oldset) { 851 #if SANITIZER_FREEBSD 852 return internal_syscall(SYSCALL(sigprocmask), how, set, oldset); 853 #else 854 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 855 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset; 856 return internal_syscall(SYSCALL(rt_sigprocmask), (uptr)how, (uptr)k_set, 857 (uptr)k_oldset, sizeof(__sanitizer_kernel_sigset_t)); 858 #endif 859 } 860 861 void internal_sigfillset(__sanitizer_sigset_t *set) { 862 internal_memset(set, 0xff, sizeof(*set)); 863 } 864 865 void internal_sigemptyset(__sanitizer_sigset_t *set) { 866 internal_memset(set, 0, sizeof(*set)); 867 } 868 869 #if SANITIZER_LINUX 870 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 871 signum -= 1; 872 CHECK_GE(signum, 0); 873 CHECK_LT(signum, sizeof(*set) * 8); 874 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 875 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 876 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 877 k_set->sig[idx] &= ~(1 << bit); 878 } 879 880 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 881 signum -= 1; 882 CHECK_GE(signum, 0); 883 CHECK_LT(signum, sizeof(*set) * 8); 884 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 885 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 886 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 887 return k_set->sig[idx] & (1 << bit); 888 } 889 #elif SANITIZER_FREEBSD 890 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 891 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 892 sigdelset(rset, signum); 893 } 894 895 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 896 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 897 return sigismember(rset, signum); 898 } 899 #endif 900 #endif // !SANITIZER_SOLARIS 901 902 #if !SANITIZER_NETBSD 903 // ThreadLister implementation. 904 ThreadLister::ThreadLister(pid_t pid) : pid_(pid), buffer_(4096) { 905 char task_directory_path[80]; 906 internal_snprintf(task_directory_path, sizeof(task_directory_path), 907 "/proc/%d/task/", pid); 908 descriptor_ = internal_open(task_directory_path, O_RDONLY | O_DIRECTORY); 909 if (internal_iserror(descriptor_)) { 910 Report("Can't open /proc/%d/task for reading.\n", pid); 911 } 912 } 913 914 ThreadLister::Result ThreadLister::ListThreads( 915 InternalMmapVector<tid_t> *threads) { 916 if (internal_iserror(descriptor_)) 917 return Error; 918 internal_lseek(descriptor_, 0, SEEK_SET); 919 threads->clear(); 920 921 Result result = Ok; 922 for (bool first_read = true;; first_read = false) { 923 // Resize to max capacity if it was downsized by IsAlive. 924 buffer_.resize(buffer_.capacity()); 925 CHECK_GE(buffer_.size(), 4096); 926 uptr read = internal_getdents( 927 descriptor_, (struct linux_dirent *)buffer_.data(), buffer_.size()); 928 if (!read) 929 return result; 930 if (internal_iserror(read)) { 931 Report("Can't read directory entries from /proc/%d/task.\n", pid_); 932 return Error; 933 } 934 935 for (uptr begin = (uptr)buffer_.data(), end = begin + read; begin < end;) { 936 struct linux_dirent *entry = (struct linux_dirent *)begin; 937 begin += entry->d_reclen; 938 if (entry->d_ino == 1) { 939 // Inode 1 is for bad blocks and also can be a reason for early return. 940 // Should be emitted if kernel tried to output terminating thread. 941 // See proc_task_readdir implementation in Linux. 942 result = Incomplete; 943 } 944 if (entry->d_ino && *entry->d_name >= '0' && *entry->d_name <= '9') 945 threads->push_back(internal_atoll(entry->d_name)); 946 } 947 948 // Now we are going to detect short-read or early EOF. In such cases Linux 949 // can return inconsistent list with missing alive threads. 950 // Code will just remember that the list can be incomplete but it will 951 // continue reads to return as much as possible. 952 if (!first_read) { 953 // The first one was a short-read by definition. 954 result = Incomplete; 955 } else if (read > buffer_.size() - 1024) { 956 // Read was close to the buffer size. So double the size and assume the 957 // worst. 958 buffer_.resize(buffer_.size() * 2); 959 result = Incomplete; 960 } else if (!threads->empty() && !IsAlive(threads->back())) { 961 // Maybe Linux early returned from read on terminated thread (!pid_alive) 962 // and failed to restore read position. 963 // See next_tid and proc_task_instantiate in Linux. 964 result = Incomplete; 965 } 966 } 967 } 968 969 bool ThreadLister::IsAlive(int tid) { 970 // /proc/%d/task/%d/status uses same call to detect alive threads as 971 // proc_task_readdir. See task_state implementation in Linux. 972 char path[80]; 973 internal_snprintf(path, sizeof(path), "/proc/%d/task/%d/status", pid_, tid); 974 if (!ReadFileToVector(path, &buffer_) || buffer_.empty()) 975 return false; 976 buffer_.push_back(0); 977 static const char kPrefix[] = "\nPPid:"; 978 const char *field = internal_strstr(buffer_.data(), kPrefix); 979 if (!field) 980 return false; 981 field += internal_strlen(kPrefix); 982 return (int)internal_atoll(field) != 0; 983 } 984 985 ThreadLister::~ThreadLister() { 986 if (!internal_iserror(descriptor_)) 987 internal_close(descriptor_); 988 } 989 #endif 990 991 #if SANITIZER_WORDSIZE == 32 992 // Take care of unusable kernel area in top gigabyte. 993 static uptr GetKernelAreaSize() { 994 #if SANITIZER_LINUX && !SANITIZER_X32 995 const uptr gbyte = 1UL << 30; 996 997 // Firstly check if there are writable segments 998 // mapped to top gigabyte (e.g. stack). 999 MemoryMappingLayout proc_maps(/*cache_enabled*/true); 1000 if (proc_maps.Error()) 1001 return 0; 1002 MemoryMappedSegment segment; 1003 while (proc_maps.Next(&segment)) { 1004 if ((segment.end >= 3 * gbyte) && segment.IsWritable()) return 0; 1005 } 1006 1007 #if !SANITIZER_ANDROID 1008 // Even if nothing is mapped, top Gb may still be accessible 1009 // if we are running on 64-bit kernel. 1010 // Uname may report misleading results if personality type 1011 // is modified (e.g. under schroot) so check this as well. 1012 struct utsname uname_info; 1013 int pers = personality(0xffffffffUL); 1014 if (!(pers & PER_MASK) && internal_uname(&uname_info) == 0 && 1015 internal_strstr(uname_info.machine, "64")) 1016 return 0; 1017 #endif // SANITIZER_ANDROID 1018 1019 // Top gigabyte is reserved for kernel. 1020 return gbyte; 1021 #else 1022 return 0; 1023 #endif // SANITIZER_LINUX && !SANITIZER_X32 1024 } 1025 #endif // SANITIZER_WORDSIZE == 32 1026 1027 uptr GetMaxVirtualAddress() { 1028 #if SANITIZER_NETBSD && defined(__x86_64__) 1029 return 0x7f7ffffff000ULL; // (0x00007f8000000000 - PAGE_SIZE) 1030 #elif SANITIZER_WORDSIZE == 64 1031 # if defined(__powerpc64__) || defined(__aarch64__) 1032 // On PowerPC64 we have two different address space layouts: 44- and 46-bit. 1033 // We somehow need to figure out which one we are using now and choose 1034 // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL. 1035 // Note that with 'ulimit -s unlimited' the stack is moved away from the top 1036 // of the address space, so simply checking the stack address is not enough. 1037 // This should (does) work for both PowerPC64 Endian modes. 1038 // Similarly, aarch64 has multiple address space layouts: 39, 42 and 47-bit. 1039 return (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1)) - 1; 1040 #elif SANITIZER_RISCV64 1041 return (1ULL << 38) - 1; 1042 # elif defined(__mips64) 1043 return (1ULL << 40) - 1; // 0x000000ffffffffffUL; 1044 # elif defined(__s390x__) 1045 return (1ULL << 53) - 1; // 0x001fffffffffffffUL; 1046 #elif defined(__sparc__) 1047 return ~(uptr)0; 1048 # else 1049 return (1ULL << 47) - 1; // 0x00007fffffffffffUL; 1050 # endif 1051 #else // SANITIZER_WORDSIZE == 32 1052 # if defined(__s390__) 1053 return (1ULL << 31) - 1; // 0x7fffffff; 1054 # else 1055 return (1ULL << 32) - 1; // 0xffffffff; 1056 # endif 1057 #endif // SANITIZER_WORDSIZE 1058 } 1059 1060 uptr GetMaxUserVirtualAddress() { 1061 uptr addr = GetMaxVirtualAddress(); 1062 #if SANITIZER_WORDSIZE == 32 && !defined(__s390__) 1063 if (!common_flags()->full_address_space) 1064 addr -= GetKernelAreaSize(); 1065 CHECK_LT(reinterpret_cast<uptr>(&addr), addr); 1066 #endif 1067 return addr; 1068 } 1069 1070 #if !SANITIZER_ANDROID 1071 uptr GetPageSize() { 1072 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__i386__)) && \ 1073 defined(EXEC_PAGESIZE) 1074 return EXEC_PAGESIZE; 1075 #elif SANITIZER_FREEBSD || SANITIZER_NETBSD 1076 // Use sysctl as sysconf can trigger interceptors internally. 1077 int pz = 0; 1078 uptr pzl = sizeof(pz); 1079 int mib[2] = {CTL_HW, HW_PAGESIZE}; 1080 int rv = internal_sysctl(mib, 2, &pz, &pzl, nullptr, 0); 1081 CHECK_EQ(rv, 0); 1082 return (uptr)pz; 1083 #elif SANITIZER_USE_GETAUXVAL 1084 return getauxval(AT_PAGESZ); 1085 #else 1086 return sysconf(_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy. 1087 #endif 1088 } 1089 #endif // !SANITIZER_ANDROID 1090 1091 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) { 1092 #if SANITIZER_SOLARIS 1093 const char *default_module_name = getexecname(); 1094 CHECK_NE(default_module_name, NULL); 1095 return internal_snprintf(buf, buf_len, "%s", default_module_name); 1096 #else 1097 #if SANITIZER_FREEBSD || SANITIZER_NETBSD 1098 #if SANITIZER_FREEBSD 1099 const int Mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1}; 1100 #else 1101 const int Mib[4] = {CTL_KERN, KERN_PROC_ARGS, -1, KERN_PROC_PATHNAME}; 1102 #endif 1103 const char *default_module_name = "kern.proc.pathname"; 1104 uptr Size = buf_len; 1105 bool IsErr = 1106 (internal_sysctl(Mib, ARRAY_SIZE(Mib), buf, &Size, NULL, 0) != 0); 1107 int readlink_error = IsErr ? errno : 0; 1108 uptr module_name_len = Size; 1109 #else 1110 const char *default_module_name = "/proc/self/exe"; 1111 uptr module_name_len = internal_readlink( 1112 default_module_name, buf, buf_len); 1113 int readlink_error; 1114 bool IsErr = internal_iserror(module_name_len, &readlink_error); 1115 #endif // SANITIZER_SOLARIS 1116 if (IsErr) { 1117 // We can't read binary name for some reason, assume it's unknown. 1118 Report("WARNING: reading executable name failed with errno %d, " 1119 "some stack frames may not be symbolized\n", readlink_error); 1120 module_name_len = internal_snprintf(buf, buf_len, "%s", 1121 default_module_name); 1122 CHECK_LT(module_name_len, buf_len); 1123 } 1124 return module_name_len; 1125 #endif 1126 } 1127 1128 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) { 1129 #if SANITIZER_LINUX 1130 char *tmpbuf; 1131 uptr tmpsize; 1132 uptr tmplen; 1133 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen, 1134 1024 * 1024)) { 1135 internal_strncpy(buf, tmpbuf, buf_len); 1136 UnmapOrDie(tmpbuf, tmpsize); 1137 return internal_strlen(buf); 1138 } 1139 #endif 1140 return ReadBinaryName(buf, buf_len); 1141 } 1142 1143 // Match full names of the form /path/to/base_name{-,.}* 1144 bool LibraryNameIs(const char *full_name, const char *base_name) { 1145 const char *name = full_name; 1146 // Strip path. 1147 while (*name != '\0') name++; 1148 while (name > full_name && *name != '/') name--; 1149 if (*name == '/') name++; 1150 uptr base_name_length = internal_strlen(base_name); 1151 if (internal_strncmp(name, base_name, base_name_length)) return false; 1152 return (name[base_name_length] == '-' || name[base_name_length] == '.'); 1153 } 1154 1155 #if !SANITIZER_ANDROID 1156 // Call cb for each region mapped by map. 1157 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) { 1158 CHECK_NE(map, nullptr); 1159 #if !SANITIZER_FREEBSD 1160 typedef ElfW(Phdr) Elf_Phdr; 1161 typedef ElfW(Ehdr) Elf_Ehdr; 1162 #endif // !SANITIZER_FREEBSD 1163 char *base = (char *)map->l_addr; 1164 Elf_Ehdr *ehdr = (Elf_Ehdr *)base; 1165 char *phdrs = base + ehdr->e_phoff; 1166 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize; 1167 1168 // Find the segment with the minimum base so we can "relocate" the p_vaddr 1169 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC 1170 // objects have a non-zero base. 1171 uptr preferred_base = (uptr)-1; 1172 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1173 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1174 if (phdr->p_type == PT_LOAD && preferred_base > (uptr)phdr->p_vaddr) 1175 preferred_base = (uptr)phdr->p_vaddr; 1176 } 1177 1178 // Compute the delta from the real base to get a relocation delta. 1179 sptr delta = (uptr)base - preferred_base; 1180 // Now we can figure out what the loader really mapped. 1181 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1182 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1183 if (phdr->p_type == PT_LOAD) { 1184 uptr seg_start = phdr->p_vaddr + delta; 1185 uptr seg_end = seg_start + phdr->p_memsz; 1186 // None of these values are aligned. We consider the ragged edges of the 1187 // load command as defined, since they are mapped from the file. 1188 seg_start = RoundDownTo(seg_start, GetPageSizeCached()); 1189 seg_end = RoundUpTo(seg_end, GetPageSizeCached()); 1190 cb((void *)seg_start, seg_end - seg_start); 1191 } 1192 } 1193 } 1194 #endif 1195 1196 #if defined(__x86_64__) && SANITIZER_LINUX 1197 // We cannot use glibc's clone wrapper, because it messes with the child 1198 // task's TLS. It writes the PID and TID of the child task to its thread 1199 // descriptor, but in our case the child task shares the thread descriptor with 1200 // the parent (because we don't know how to allocate a new thread 1201 // descriptor to keep glibc happy). So the stock version of clone(), when 1202 // used with CLONE_VM, would end up corrupting the parent's thread descriptor. 1203 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1204 int *parent_tidptr, void *newtls, int *child_tidptr) { 1205 long long res; 1206 if (!fn || !child_stack) 1207 return -EINVAL; 1208 CHECK_EQ(0, (uptr)child_stack % 16); 1209 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1210 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1211 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1212 register void *r8 __asm__("r8") = newtls; 1213 register int *r10 __asm__("r10") = child_tidptr; 1214 __asm__ __volatile__( 1215 /* %rax = syscall(%rax = SYSCALL(clone), 1216 * %rdi = flags, 1217 * %rsi = child_stack, 1218 * %rdx = parent_tidptr, 1219 * %r8 = new_tls, 1220 * %r10 = child_tidptr) 1221 */ 1222 "syscall\n" 1223 1224 /* if (%rax != 0) 1225 * return; 1226 */ 1227 "testq %%rax,%%rax\n" 1228 "jnz 1f\n" 1229 1230 /* In the child. Terminate unwind chain. */ 1231 // XXX: We should also terminate the CFI unwind chain 1232 // here. Unfortunately clang 3.2 doesn't support the 1233 // necessary CFI directives, so we skip that part. 1234 "xorq %%rbp,%%rbp\n" 1235 1236 /* Call "fn(arg)". */ 1237 "popq %%rax\n" 1238 "popq %%rdi\n" 1239 "call *%%rax\n" 1240 1241 /* Call _exit(%rax). */ 1242 "movq %%rax,%%rdi\n" 1243 "movq %2,%%rax\n" 1244 "syscall\n" 1245 1246 /* Return to parent. */ 1247 "1:\n" 1248 : "=a" (res) 1249 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1250 "S"(child_stack), 1251 "D"(flags), 1252 "d"(parent_tidptr), 1253 "r"(r8), 1254 "r"(r10) 1255 : "memory", "r11", "rcx"); 1256 return res; 1257 } 1258 #elif defined(__mips__) 1259 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1260 int *parent_tidptr, void *newtls, int *child_tidptr) { 1261 long long res; 1262 if (!fn || !child_stack) 1263 return -EINVAL; 1264 CHECK_EQ(0, (uptr)child_stack % 16); 1265 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1266 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1267 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1268 register void *a3 __asm__("$7") = newtls; 1269 register int *a4 __asm__("$8") = child_tidptr; 1270 // We don't have proper CFI directives here because it requires alot of code 1271 // for very marginal benefits. 1272 __asm__ __volatile__( 1273 /* $v0 = syscall($v0 = __NR_clone, 1274 * $a0 = flags, 1275 * $a1 = child_stack, 1276 * $a2 = parent_tidptr, 1277 * $a3 = new_tls, 1278 * $a4 = child_tidptr) 1279 */ 1280 ".cprestore 16;\n" 1281 "move $4,%1;\n" 1282 "move $5,%2;\n" 1283 "move $6,%3;\n" 1284 "move $7,%4;\n" 1285 /* Store the fifth argument on stack 1286 * if we are using 32-bit abi. 1287 */ 1288 #if SANITIZER_WORDSIZE == 32 1289 "lw %5,16($29);\n" 1290 #else 1291 "move $8,%5;\n" 1292 #endif 1293 "li $2,%6;\n" 1294 "syscall;\n" 1295 1296 /* if ($v0 != 0) 1297 * return; 1298 */ 1299 "bnez $2,1f;\n" 1300 1301 /* Call "fn(arg)". */ 1302 #if SANITIZER_WORDSIZE == 32 1303 #ifdef __BIG_ENDIAN__ 1304 "lw $25,4($29);\n" 1305 "lw $4,12($29);\n" 1306 #else 1307 "lw $25,0($29);\n" 1308 "lw $4,8($29);\n" 1309 #endif 1310 #else 1311 "ld $25,0($29);\n" 1312 "ld $4,8($29);\n" 1313 #endif 1314 "jal $25;\n" 1315 1316 /* Call _exit($v0). */ 1317 "move $4,$2;\n" 1318 "li $2,%7;\n" 1319 "syscall;\n" 1320 1321 /* Return to parent. */ 1322 "1:\n" 1323 : "=r" (res) 1324 : "r"(flags), 1325 "r"(child_stack), 1326 "r"(parent_tidptr), 1327 "r"(a3), 1328 "r"(a4), 1329 "i"(__NR_clone), 1330 "i"(__NR_exit) 1331 : "memory", "$29" ); 1332 return res; 1333 } 1334 #elif SANITIZER_RISCV64 1335 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1336 int *parent_tidptr, void *newtls, int *child_tidptr) { 1337 long long res; 1338 if (!fn || !child_stack) 1339 return -EINVAL; 1340 CHECK_EQ(0, (uptr)child_stack % 16); 1341 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1342 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1343 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1344 1345 register int (*__fn)(void *) __asm__("a0") = fn; 1346 register void *__stack __asm__("a1") = child_stack; 1347 register int __flags __asm__("a2") = flags; 1348 register void *__arg __asm__("a3") = arg; 1349 register int *__ptid __asm__("a4") = parent_tidptr; 1350 register void *__tls __asm__("a5") = newtls; 1351 register int *__ctid __asm__("a6") = child_tidptr; 1352 1353 __asm__ __volatile__( 1354 "mv a0,a2\n" /* flags */ 1355 "mv a2,a4\n" /* ptid */ 1356 "mv a3,a5\n" /* tls */ 1357 "mv a4,a6\n" /* ctid */ 1358 "addi a7, zero, %9\n" /* clone */ 1359 1360 "ecall\n" 1361 1362 /* if (%r0 != 0) 1363 * return %r0; 1364 */ 1365 "bnez a0, 1f\n" 1366 1367 /* In the child, now. Call "fn(arg)". */ 1368 "ld a0, 8(sp)\n" 1369 "ld a1, 16(sp)\n" 1370 "jalr a1\n" 1371 1372 /* Call _exit(%r0). */ 1373 "addi a7, zero, %10\n" 1374 "ecall\n" 1375 "1:\n" 1376 1377 : "=r"(res) 1378 : "i"(-EINVAL), "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg), 1379 "r"(__ptid), "r"(__tls), "r"(__ctid), "i"(__NR_clone), "i"(__NR_exit) 1380 : "ra", "memory"); 1381 return res; 1382 } 1383 #elif defined(__aarch64__) 1384 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1385 int *parent_tidptr, void *newtls, int *child_tidptr) { 1386 long long res; 1387 if (!fn || !child_stack) 1388 return -EINVAL; 1389 CHECK_EQ(0, (uptr)child_stack % 16); 1390 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1391 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1392 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1393 1394 register int (*__fn)(void *) __asm__("x0") = fn; 1395 register void *__stack __asm__("x1") = child_stack; 1396 register int __flags __asm__("x2") = flags; 1397 register void *__arg __asm__("x3") = arg; 1398 register int *__ptid __asm__("x4") = parent_tidptr; 1399 register void *__tls __asm__("x5") = newtls; 1400 register int *__ctid __asm__("x6") = child_tidptr; 1401 1402 __asm__ __volatile__( 1403 "mov x0,x2\n" /* flags */ 1404 "mov x2,x4\n" /* ptid */ 1405 "mov x3,x5\n" /* tls */ 1406 "mov x4,x6\n" /* ctid */ 1407 "mov x8,%9\n" /* clone */ 1408 1409 "svc 0x0\n" 1410 1411 /* if (%r0 != 0) 1412 * return %r0; 1413 */ 1414 "cmp x0, #0\n" 1415 "bne 1f\n" 1416 1417 /* In the child, now. Call "fn(arg)". */ 1418 "ldp x1, x0, [sp], #16\n" 1419 "blr x1\n" 1420 1421 /* Call _exit(%r0). */ 1422 "mov x8, %10\n" 1423 "svc 0x0\n" 1424 "1:\n" 1425 1426 : "=r" (res) 1427 : "i"(-EINVAL), 1428 "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg), 1429 "r"(__ptid), "r"(__tls), "r"(__ctid), 1430 "i"(__NR_clone), "i"(__NR_exit) 1431 : "x30", "memory"); 1432 return res; 1433 } 1434 #elif defined(__powerpc64__) 1435 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1436 int *parent_tidptr, void *newtls, int *child_tidptr) { 1437 long long res; 1438 // Stack frame structure. 1439 #if SANITIZER_PPC64V1 1440 // Back chain == 0 (SP + 112) 1441 // Frame (112 bytes): 1442 // Parameter save area (SP + 48), 8 doublewords 1443 // TOC save area (SP + 40) 1444 // Link editor doubleword (SP + 32) 1445 // Compiler doubleword (SP + 24) 1446 // LR save area (SP + 16) 1447 // CR save area (SP + 8) 1448 // Back chain (SP + 0) 1449 # define FRAME_SIZE 112 1450 # define FRAME_TOC_SAVE_OFFSET 40 1451 #elif SANITIZER_PPC64V2 1452 // Back chain == 0 (SP + 32) 1453 // Frame (32 bytes): 1454 // TOC save area (SP + 24) 1455 // LR save area (SP + 16) 1456 // CR save area (SP + 8) 1457 // Back chain (SP + 0) 1458 # define FRAME_SIZE 32 1459 # define FRAME_TOC_SAVE_OFFSET 24 1460 #else 1461 # error "Unsupported PPC64 ABI" 1462 #endif 1463 if (!fn || !child_stack) 1464 return -EINVAL; 1465 CHECK_EQ(0, (uptr)child_stack % 16); 1466 1467 register int (*__fn)(void *) __asm__("r3") = fn; 1468 register void *__cstack __asm__("r4") = child_stack; 1469 register int __flags __asm__("r5") = flags; 1470 register void *__arg __asm__("r6") = arg; 1471 register int *__ptidptr __asm__("r7") = parent_tidptr; 1472 register void *__newtls __asm__("r8") = newtls; 1473 register int *__ctidptr __asm__("r9") = child_tidptr; 1474 1475 __asm__ __volatile__( 1476 /* fn and arg are saved across the syscall */ 1477 "mr 28, %5\n\t" 1478 "mr 27, %8\n\t" 1479 1480 /* syscall 1481 r0 == __NR_clone 1482 r3 == flags 1483 r4 == child_stack 1484 r5 == parent_tidptr 1485 r6 == newtls 1486 r7 == child_tidptr */ 1487 "mr 3, %7\n\t" 1488 "mr 5, %9\n\t" 1489 "mr 6, %10\n\t" 1490 "mr 7, %11\n\t" 1491 "li 0, %3\n\t" 1492 "sc\n\t" 1493 1494 /* Test if syscall was successful */ 1495 "cmpdi cr1, 3, 0\n\t" 1496 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t" 1497 "bne- cr1, 1f\n\t" 1498 1499 /* Set up stack frame */ 1500 "li 29, 0\n\t" 1501 "stdu 29, -8(1)\n\t" 1502 "stdu 1, -%12(1)\n\t" 1503 /* Do the function call */ 1504 "std 2, %13(1)\n\t" 1505 #if SANITIZER_PPC64V1 1506 "ld 0, 0(28)\n\t" 1507 "ld 2, 8(28)\n\t" 1508 "mtctr 0\n\t" 1509 #elif SANITIZER_PPC64V2 1510 "mr 12, 28\n\t" 1511 "mtctr 12\n\t" 1512 #else 1513 # error "Unsupported PPC64 ABI" 1514 #endif 1515 "mr 3, 27\n\t" 1516 "bctrl\n\t" 1517 "ld 2, %13(1)\n\t" 1518 1519 /* Call _exit(r3) */ 1520 "li 0, %4\n\t" 1521 "sc\n\t" 1522 1523 /* Return to parent */ 1524 "1:\n\t" 1525 "mr %0, 3\n\t" 1526 : "=r" (res) 1527 : "0" (-1), 1528 "i" (EINVAL), 1529 "i" (__NR_clone), 1530 "i" (__NR_exit), 1531 "r" (__fn), 1532 "r" (__cstack), 1533 "r" (__flags), 1534 "r" (__arg), 1535 "r" (__ptidptr), 1536 "r" (__newtls), 1537 "r" (__ctidptr), 1538 "i" (FRAME_SIZE), 1539 "i" (FRAME_TOC_SAVE_OFFSET) 1540 : "cr0", "cr1", "memory", "ctr", "r0", "r27", "r28", "r29"); 1541 return res; 1542 } 1543 #elif defined(__i386__) && SANITIZER_LINUX 1544 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1545 int *parent_tidptr, void *newtls, int *child_tidptr) { 1546 int res; 1547 if (!fn || !child_stack) 1548 return -EINVAL; 1549 CHECK_EQ(0, (uptr)child_stack % 16); 1550 child_stack = (char *)child_stack - 7 * sizeof(unsigned int); 1551 ((unsigned int *)child_stack)[0] = (uptr)flags; 1552 ((unsigned int *)child_stack)[1] = (uptr)0; 1553 ((unsigned int *)child_stack)[2] = (uptr)fn; 1554 ((unsigned int *)child_stack)[3] = (uptr)arg; 1555 __asm__ __volatile__( 1556 /* %eax = syscall(%eax = SYSCALL(clone), 1557 * %ebx = flags, 1558 * %ecx = child_stack, 1559 * %edx = parent_tidptr, 1560 * %esi = new_tls, 1561 * %edi = child_tidptr) 1562 */ 1563 1564 /* Obtain flags */ 1565 "movl (%%ecx), %%ebx\n" 1566 /* Do the system call */ 1567 "pushl %%ebx\n" 1568 "pushl %%esi\n" 1569 "pushl %%edi\n" 1570 /* Remember the flag value. */ 1571 "movl %%ebx, (%%ecx)\n" 1572 "int $0x80\n" 1573 "popl %%edi\n" 1574 "popl %%esi\n" 1575 "popl %%ebx\n" 1576 1577 /* if (%eax != 0) 1578 * return; 1579 */ 1580 1581 "test %%eax,%%eax\n" 1582 "jnz 1f\n" 1583 1584 /* terminate the stack frame */ 1585 "xorl %%ebp,%%ebp\n" 1586 /* Call FN. */ 1587 "call *%%ebx\n" 1588 #ifdef PIC 1589 "call here\n" 1590 "here:\n" 1591 "popl %%ebx\n" 1592 "addl $_GLOBAL_OFFSET_TABLE_+[.-here], %%ebx\n" 1593 #endif 1594 /* Call exit */ 1595 "movl %%eax, %%ebx\n" 1596 "movl %2, %%eax\n" 1597 "int $0x80\n" 1598 "1:\n" 1599 : "=a" (res) 1600 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1601 "c"(child_stack), 1602 "d"(parent_tidptr), 1603 "S"(newtls), 1604 "D"(child_tidptr) 1605 : "memory"); 1606 return res; 1607 } 1608 #elif defined(__arm__) && SANITIZER_LINUX 1609 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1610 int *parent_tidptr, void *newtls, int *child_tidptr) { 1611 unsigned int res; 1612 if (!fn || !child_stack) 1613 return -EINVAL; 1614 child_stack = (char *)child_stack - 2 * sizeof(unsigned int); 1615 ((unsigned int *)child_stack)[0] = (uptr)fn; 1616 ((unsigned int *)child_stack)[1] = (uptr)arg; 1617 register int r0 __asm__("r0") = flags; 1618 register void *r1 __asm__("r1") = child_stack; 1619 register int *r2 __asm__("r2") = parent_tidptr; 1620 register void *r3 __asm__("r3") = newtls; 1621 register int *r4 __asm__("r4") = child_tidptr; 1622 register int r7 __asm__("r7") = __NR_clone; 1623 1624 #if __ARM_ARCH > 4 || defined (__ARM_ARCH_4T__) 1625 # define ARCH_HAS_BX 1626 #endif 1627 #if __ARM_ARCH > 4 1628 # define ARCH_HAS_BLX 1629 #endif 1630 1631 #ifdef ARCH_HAS_BX 1632 # ifdef ARCH_HAS_BLX 1633 # define BLX(R) "blx " #R "\n" 1634 # else 1635 # define BLX(R) "mov lr, pc; bx " #R "\n" 1636 # endif 1637 #else 1638 # define BLX(R) "mov lr, pc; mov pc," #R "\n" 1639 #endif 1640 1641 __asm__ __volatile__( 1642 /* %r0 = syscall(%r7 = SYSCALL(clone), 1643 * %r0 = flags, 1644 * %r1 = child_stack, 1645 * %r2 = parent_tidptr, 1646 * %r3 = new_tls, 1647 * %r4 = child_tidptr) 1648 */ 1649 1650 /* Do the system call */ 1651 "swi 0x0\n" 1652 1653 /* if (%r0 != 0) 1654 * return %r0; 1655 */ 1656 "cmp r0, #0\n" 1657 "bne 1f\n" 1658 1659 /* In the child, now. Call "fn(arg)". */ 1660 "ldr r0, [sp, #4]\n" 1661 "ldr ip, [sp], #8\n" 1662 BLX(ip) 1663 /* Call _exit(%r0). */ 1664 "mov r7, %7\n" 1665 "swi 0x0\n" 1666 "1:\n" 1667 "mov %0, r0\n" 1668 : "=r"(res) 1669 : "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r7), 1670 "i"(__NR_exit) 1671 : "memory"); 1672 return res; 1673 } 1674 #endif // defined(__x86_64__) && SANITIZER_LINUX 1675 1676 #if SANITIZER_LINUX 1677 int internal_uname(struct utsname *buf) { 1678 return internal_syscall(SYSCALL(uname), buf); 1679 } 1680 #endif 1681 1682 #if SANITIZER_ANDROID 1683 #if __ANDROID_API__ < 21 1684 extern "C" __attribute__((weak)) int dl_iterate_phdr( 1685 int (*)(struct dl_phdr_info *, size_t, void *), void *); 1686 #endif 1687 1688 static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size, 1689 void *data) { 1690 // Any name starting with "lib" indicates a bug in L where library base names 1691 // are returned instead of paths. 1692 if (info->dlpi_name && info->dlpi_name[0] == 'l' && 1693 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') { 1694 *(bool *)data = true; 1695 return 1; 1696 } 1697 return 0; 1698 } 1699 1700 static atomic_uint32_t android_api_level; 1701 1702 static AndroidApiLevel AndroidDetectApiLevelStatic() { 1703 #if __ANDROID_API__ <= 19 1704 return ANDROID_KITKAT; 1705 #elif __ANDROID_API__ <= 22 1706 return ANDROID_LOLLIPOP_MR1; 1707 #else 1708 return ANDROID_POST_LOLLIPOP; 1709 #endif 1710 } 1711 1712 static AndroidApiLevel AndroidDetectApiLevel() { 1713 if (!&dl_iterate_phdr) 1714 return ANDROID_KITKAT; // K or lower 1715 bool base_name_seen = false; 1716 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen); 1717 if (base_name_seen) 1718 return ANDROID_LOLLIPOP_MR1; // L MR1 1719 return ANDROID_POST_LOLLIPOP; // post-L 1720 // Plain L (API level 21) is completely broken wrt ASan and not very 1721 // interesting to detect. 1722 } 1723 1724 extern "C" __attribute__((weak)) void* _DYNAMIC; 1725 1726 AndroidApiLevel AndroidGetApiLevel() { 1727 AndroidApiLevel level = 1728 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed); 1729 if (level) return level; 1730 level = &_DYNAMIC == nullptr ? AndroidDetectApiLevelStatic() 1731 : AndroidDetectApiLevel(); 1732 atomic_store(&android_api_level, level, memory_order_relaxed); 1733 return level; 1734 } 1735 1736 #endif 1737 1738 static HandleSignalMode GetHandleSignalModeImpl(int signum) { 1739 switch (signum) { 1740 case SIGABRT: 1741 return common_flags()->handle_abort; 1742 case SIGILL: 1743 return common_flags()->handle_sigill; 1744 case SIGTRAP: 1745 return common_flags()->handle_sigtrap; 1746 case SIGFPE: 1747 return common_flags()->handle_sigfpe; 1748 case SIGSEGV: 1749 return common_flags()->handle_segv; 1750 case SIGBUS: 1751 return common_flags()->handle_sigbus; 1752 } 1753 return kHandleSignalNo; 1754 } 1755 1756 HandleSignalMode GetHandleSignalMode(int signum) { 1757 HandleSignalMode result = GetHandleSignalModeImpl(signum); 1758 if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler) 1759 return kHandleSignalExclusive; 1760 return result; 1761 } 1762 1763 #if !SANITIZER_GO 1764 void *internal_start_thread(void *(*func)(void *arg), void *arg) { 1765 // Start the thread with signals blocked, otherwise it can steal user signals. 1766 __sanitizer_sigset_t set, old; 1767 internal_sigfillset(&set); 1768 #if SANITIZER_LINUX && !SANITIZER_ANDROID 1769 // Glibc uses SIGSETXID signal during setuid call. If this signal is blocked 1770 // on any thread, setuid call hangs (see test/tsan/setuid.c). 1771 internal_sigdelset(&set, 33); 1772 #endif 1773 internal_sigprocmask(SIG_SETMASK, &set, &old); 1774 void *th; 1775 real_pthread_create(&th, nullptr, func, arg); 1776 internal_sigprocmask(SIG_SETMASK, &old, nullptr); 1777 return th; 1778 } 1779 1780 void internal_join_thread(void *th) { 1781 real_pthread_join(th, nullptr); 1782 } 1783 #else 1784 void *internal_start_thread(void *(*func)(void *), void *arg) { return 0; } 1785 1786 void internal_join_thread(void *th) {} 1787 #endif 1788 1789 #if defined(__aarch64__) 1790 // Android headers in the older NDK releases miss this definition. 1791 struct __sanitizer_esr_context { 1792 struct _aarch64_ctx head; 1793 uint64_t esr; 1794 }; 1795 1796 static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) { 1797 static const u32 kEsrMagic = 0x45535201; 1798 u8 *aux = ucontext->uc_mcontext.__reserved; 1799 while (true) { 1800 _aarch64_ctx *ctx = (_aarch64_ctx *)aux; 1801 if (ctx->size == 0) break; 1802 if (ctx->magic == kEsrMagic) { 1803 *esr = ((__sanitizer_esr_context *)ctx)->esr; 1804 return true; 1805 } 1806 aux += ctx->size; 1807 } 1808 return false; 1809 } 1810 #endif 1811 1812 using Context = ucontext_t; 1813 1814 SignalContext::WriteFlag SignalContext::GetWriteFlag() const { 1815 Context *ucontext = (Context *)context; 1816 #if defined(__x86_64__) || defined(__i386__) 1817 static const uptr PF_WRITE = 1U << 1; 1818 #if SANITIZER_FREEBSD 1819 uptr err = ucontext->uc_mcontext.mc_err; 1820 #elif SANITIZER_NETBSD 1821 uptr err = ucontext->uc_mcontext.__gregs[_REG_ERR]; 1822 #elif SANITIZER_SOLARIS && defined(__i386__) 1823 const int Err = 13; 1824 uptr err = ucontext->uc_mcontext.gregs[Err]; 1825 #else 1826 uptr err = ucontext->uc_mcontext.gregs[REG_ERR]; 1827 #endif // SANITIZER_FREEBSD 1828 return err & PF_WRITE ? WRITE : READ; 1829 #elif defined(__mips__) 1830 uint32_t *exception_source; 1831 uint32_t faulty_instruction; 1832 uint32_t op_code; 1833 1834 exception_source = (uint32_t *)ucontext->uc_mcontext.pc; 1835 faulty_instruction = (uint32_t)(*exception_source); 1836 1837 op_code = (faulty_instruction >> 26) & 0x3f; 1838 1839 // FIXME: Add support for FPU, microMIPS, DSP, MSA memory instructions. 1840 switch (op_code) { 1841 case 0x28: // sb 1842 case 0x29: // sh 1843 case 0x2b: // sw 1844 case 0x3f: // sd 1845 #if __mips_isa_rev < 6 1846 case 0x2c: // sdl 1847 case 0x2d: // sdr 1848 case 0x2a: // swl 1849 case 0x2e: // swr 1850 #endif 1851 return SignalContext::WRITE; 1852 1853 case 0x20: // lb 1854 case 0x24: // lbu 1855 case 0x21: // lh 1856 case 0x25: // lhu 1857 case 0x23: // lw 1858 case 0x27: // lwu 1859 case 0x37: // ld 1860 #if __mips_isa_rev < 6 1861 case 0x1a: // ldl 1862 case 0x1b: // ldr 1863 case 0x22: // lwl 1864 case 0x26: // lwr 1865 #endif 1866 return SignalContext::READ; 1867 #if __mips_isa_rev == 6 1868 case 0x3b: // pcrel 1869 op_code = (faulty_instruction >> 19) & 0x3; 1870 switch (op_code) { 1871 case 0x1: // lwpc 1872 case 0x2: // lwupc 1873 return SignalContext::READ; 1874 } 1875 #endif 1876 } 1877 return SignalContext::UNKNOWN; 1878 #elif defined(__arm__) 1879 static const uptr FSR_WRITE = 1U << 11; 1880 uptr fsr = ucontext->uc_mcontext.error_code; 1881 return fsr & FSR_WRITE ? WRITE : READ; 1882 #elif defined(__aarch64__) 1883 static const u64 ESR_ELx_WNR = 1U << 6; 1884 u64 esr; 1885 if (!Aarch64GetESR(ucontext, &esr)) return UNKNOWN; 1886 return esr & ESR_ELx_WNR ? WRITE : READ; 1887 #elif defined(__sparc__) 1888 // Decode the instruction to determine the access type. 1889 // From OpenSolaris $SRC/uts/sun4/os/trap.c (get_accesstype). 1890 #if SANITIZER_SOLARIS 1891 uptr pc = ucontext->uc_mcontext.gregs[REG_PC]; 1892 #else 1893 // Historical BSDism here. 1894 struct sigcontext *scontext = (struct sigcontext *)context; 1895 #if defined(__arch64__) 1896 uptr pc = scontext->sigc_regs.tpc; 1897 #else 1898 uptr pc = scontext->si_regs.pc; 1899 #endif 1900 #endif 1901 u32 instr = *(u32 *)pc; 1902 return (instr >> 21) & 1 ? WRITE: READ; 1903 #elif defined(__riscv) 1904 unsigned long pc = ucontext->uc_mcontext.__gregs[REG_PC]; 1905 unsigned faulty_instruction = *(uint16_t *)pc; 1906 1907 #if defined(__riscv_compressed) 1908 if ((faulty_instruction & 0x3) != 0x3) { // it's a compressed instruction 1909 // set op_bits to the instruction bits [1, 0, 15, 14, 13] 1910 unsigned op_bits = 1911 ((faulty_instruction & 0x3) << 3) | (faulty_instruction >> 13); 1912 unsigned rd = faulty_instruction & 0xF80; // bits 7-11, inclusive 1913 switch (op_bits) { 1914 case 0b10'010: // c.lwsp (rd != x0) 1915 #if __riscv_xlen == 64 1916 case 0b10'011: // c.ldsp (rd != x0) 1917 #endif 1918 return rd ? SignalContext::READ : SignalContext::UNKNOWN; 1919 case 0b00'010: // c.lw 1920 #if __riscv_flen >= 32 && __riscv_xlen == 32 1921 case 0b10'011: // c.flwsp 1922 #endif 1923 #if __riscv_flen >= 32 || __riscv_xlen == 64 1924 case 0b00'011: // c.flw / c.ld 1925 #endif 1926 #if __riscv_flen == 64 1927 case 0b00'001: // c.fld 1928 case 0b10'001: // c.fldsp 1929 #endif 1930 return SignalContext::READ; 1931 case 0b00'110: // c.sw 1932 case 0b10'110: // c.swsp 1933 #if __riscv_flen >= 32 || __riscv_xlen == 64 1934 case 0b00'111: // c.fsw / c.sd 1935 case 0b10'111: // c.fswsp / c.sdsp 1936 #endif 1937 #if __riscv_flen == 64 1938 case 0b00'101: // c.fsd 1939 case 0b10'101: // c.fsdsp 1940 #endif 1941 return SignalContext::WRITE; 1942 default: 1943 return SignalContext::UNKNOWN; 1944 } 1945 } 1946 #endif 1947 1948 unsigned opcode = faulty_instruction & 0x7f; // lower 7 bits 1949 unsigned funct3 = (faulty_instruction >> 12) & 0x7; // bits 12-14, inclusive 1950 switch (opcode) { 1951 case 0b0000011: // loads 1952 switch (funct3) { 1953 case 0b000: // lb 1954 case 0b001: // lh 1955 case 0b010: // lw 1956 #if __riscv_xlen == 64 1957 case 0b011: // ld 1958 #endif 1959 case 0b100: // lbu 1960 case 0b101: // lhu 1961 return SignalContext::READ; 1962 default: 1963 return SignalContext::UNKNOWN; 1964 } 1965 case 0b0100011: // stores 1966 switch (funct3) { 1967 case 0b000: // sb 1968 case 0b001: // sh 1969 case 0b010: // sw 1970 #if __riscv_xlen == 64 1971 case 0b011: // sd 1972 #endif 1973 return SignalContext::WRITE; 1974 default: 1975 return SignalContext::UNKNOWN; 1976 } 1977 #if __riscv_flen >= 32 1978 case 0b0000111: // floating-point loads 1979 switch (funct3) { 1980 case 0b010: // flw 1981 #if __riscv_flen == 64 1982 case 0b011: // fld 1983 #endif 1984 return SignalContext::READ; 1985 default: 1986 return SignalContext::UNKNOWN; 1987 } 1988 case 0b0100111: // floating-point stores 1989 switch (funct3) { 1990 case 0b010: // fsw 1991 #if __riscv_flen == 64 1992 case 0b011: // fsd 1993 #endif 1994 return SignalContext::WRITE; 1995 default: 1996 return SignalContext::UNKNOWN; 1997 } 1998 #endif 1999 default: 2000 return SignalContext::UNKNOWN; 2001 } 2002 #else 2003 (void)ucontext; 2004 return UNKNOWN; // FIXME: Implement. 2005 #endif 2006 } 2007 2008 bool SignalContext::IsTrueFaultingAddress() const { 2009 auto si = static_cast<const siginfo_t *>(siginfo); 2010 // SIGSEGV signals without a true fault address have si_code set to 128. 2011 return si->si_signo == SIGSEGV && si->si_code != 128; 2012 } 2013 2014 void SignalContext::DumpAllRegisters(void *context) { 2015 // FIXME: Implement this. 2016 } 2017 2018 static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) { 2019 #if SANITIZER_NETBSD 2020 // This covers all NetBSD architectures 2021 ucontext_t *ucontext = (ucontext_t *)context; 2022 *pc = _UC_MACHINE_PC(ucontext); 2023 *bp = _UC_MACHINE_FP(ucontext); 2024 *sp = _UC_MACHINE_SP(ucontext); 2025 #elif defined(__arm__) 2026 ucontext_t *ucontext = (ucontext_t*)context; 2027 *pc = ucontext->uc_mcontext.arm_pc; 2028 *bp = ucontext->uc_mcontext.arm_fp; 2029 *sp = ucontext->uc_mcontext.arm_sp; 2030 #elif defined(__aarch64__) 2031 ucontext_t *ucontext = (ucontext_t*)context; 2032 *pc = ucontext->uc_mcontext.pc; 2033 *bp = ucontext->uc_mcontext.regs[29]; 2034 *sp = ucontext->uc_mcontext.sp; 2035 #elif defined(__hppa__) 2036 ucontext_t *ucontext = (ucontext_t*)context; 2037 *pc = ucontext->uc_mcontext.sc_iaoq[0]; 2038 /* GCC uses %r3 whenever a frame pointer is needed. */ 2039 *bp = ucontext->uc_mcontext.sc_gr[3]; 2040 *sp = ucontext->uc_mcontext.sc_gr[30]; 2041 #elif defined(__x86_64__) 2042 # if SANITIZER_FREEBSD 2043 ucontext_t *ucontext = (ucontext_t*)context; 2044 *pc = ucontext->uc_mcontext.mc_rip; 2045 *bp = ucontext->uc_mcontext.mc_rbp; 2046 *sp = ucontext->uc_mcontext.mc_rsp; 2047 # else 2048 ucontext_t *ucontext = (ucontext_t*)context; 2049 *pc = ucontext->uc_mcontext.gregs[REG_RIP]; 2050 *bp = ucontext->uc_mcontext.gregs[REG_RBP]; 2051 *sp = ucontext->uc_mcontext.gregs[REG_RSP]; 2052 # endif 2053 #elif defined(__i386__) 2054 # if SANITIZER_FREEBSD 2055 ucontext_t *ucontext = (ucontext_t*)context; 2056 *pc = ucontext->uc_mcontext.mc_eip; 2057 *bp = ucontext->uc_mcontext.mc_ebp; 2058 *sp = ucontext->uc_mcontext.mc_esp; 2059 # else 2060 ucontext_t *ucontext = (ucontext_t*)context; 2061 # if SANITIZER_SOLARIS 2062 /* Use the numeric values: the symbolic ones are undefined by llvm 2063 include/llvm/Support/Solaris.h. */ 2064 # ifndef REG_EIP 2065 # define REG_EIP 14 // REG_PC 2066 # endif 2067 # ifndef REG_EBP 2068 # define REG_EBP 6 // REG_FP 2069 # endif 2070 # ifndef REG_UESP 2071 # define REG_UESP 17 // REG_SP 2072 # endif 2073 # endif 2074 *pc = ucontext->uc_mcontext.gregs[REG_EIP]; 2075 *bp = ucontext->uc_mcontext.gregs[REG_EBP]; 2076 *sp = ucontext->uc_mcontext.gregs[REG_UESP]; 2077 # endif 2078 #elif defined(__powerpc__) || defined(__powerpc64__) 2079 ucontext_t *ucontext = (ucontext_t*)context; 2080 *pc = ucontext->uc_mcontext.regs->nip; 2081 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1]; 2082 // The powerpc{,64}-linux ABIs do not specify r31 as the frame 2083 // pointer, but GCC always uses r31 when we need a frame pointer. 2084 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31]; 2085 #elif defined(__sparc__) 2086 #if defined(__arch64__) || defined(__sparcv9) 2087 #define STACK_BIAS 2047 2088 #else 2089 #define STACK_BIAS 0 2090 # endif 2091 # if SANITIZER_SOLARIS 2092 ucontext_t *ucontext = (ucontext_t *)context; 2093 *pc = ucontext->uc_mcontext.gregs[REG_PC]; 2094 *sp = ucontext->uc_mcontext.gregs[REG_O6] + STACK_BIAS; 2095 #else 2096 // Historical BSDism here. 2097 struct sigcontext *scontext = (struct sigcontext *)context; 2098 #if defined(__arch64__) 2099 *pc = scontext->sigc_regs.tpc; 2100 *sp = scontext->sigc_regs.u_regs[14] + STACK_BIAS; 2101 #else 2102 *pc = scontext->si_regs.pc; 2103 *sp = scontext->si_regs.u_regs[14]; 2104 #endif 2105 # endif 2106 *bp = (uptr)((uhwptr *)*sp)[14] + STACK_BIAS; 2107 #elif defined(__mips__) 2108 ucontext_t *ucontext = (ucontext_t*)context; 2109 *pc = ucontext->uc_mcontext.pc; 2110 *bp = ucontext->uc_mcontext.gregs[30]; 2111 *sp = ucontext->uc_mcontext.gregs[29]; 2112 #elif defined(__s390__) 2113 ucontext_t *ucontext = (ucontext_t*)context; 2114 # if defined(__s390x__) 2115 *pc = ucontext->uc_mcontext.psw.addr; 2116 # else 2117 *pc = ucontext->uc_mcontext.psw.addr & 0x7fffffff; 2118 # endif 2119 *bp = ucontext->uc_mcontext.gregs[11]; 2120 *sp = ucontext->uc_mcontext.gregs[15]; 2121 #elif defined(__riscv) 2122 ucontext_t *ucontext = (ucontext_t*)context; 2123 *pc = ucontext->uc_mcontext.__gregs[REG_PC]; 2124 *bp = ucontext->uc_mcontext.__gregs[REG_S0]; 2125 *sp = ucontext->uc_mcontext.__gregs[REG_SP]; 2126 #else 2127 # error "Unsupported arch" 2128 #endif 2129 } 2130 2131 void SignalContext::InitPcSpBp() { GetPcSpBp(context, &pc, &sp, &bp); } 2132 2133 void InitializePlatformEarly() { 2134 // Do nothing. 2135 } 2136 2137 void MaybeReexec() { 2138 // No need to re-exec on Linux. 2139 } 2140 2141 void CheckASLR() { 2142 #if SANITIZER_NETBSD 2143 int mib[3]; 2144 int paxflags; 2145 uptr len = sizeof(paxflags); 2146 2147 mib[0] = CTL_PROC; 2148 mib[1] = internal_getpid(); 2149 mib[2] = PROC_PID_PAXFLAGS; 2150 2151 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2152 Printf("sysctl failed\n"); 2153 Die(); 2154 } 2155 2156 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_ASLR)) { 2157 Printf("This sanitizer is not compatible with enabled ASLR.\n" 2158 "To disable ASLR, please run \"paxctl +a %s\" and try again.\n", 2159 GetArgv()[0]); 2160 Die(); 2161 } 2162 #elif SANITIZER_PPC64V2 2163 // Disable ASLR for Linux PPC64LE. 2164 int old_personality = personality(0xffffffff); 2165 if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) { 2166 VReport(1, "WARNING: Program is being run with address space layout " 2167 "randomization (ASLR) enabled which prevents the thread and " 2168 "memory sanitizers from working on powerpc64le.\n" 2169 "ASLR will be disabled and the program re-executed.\n"); 2170 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1); 2171 ReExec(); 2172 } 2173 #elif SANITIZER_FREEBSD 2174 int aslr_pie; 2175 uptr len = sizeof(aslr_pie); 2176 #if SANITIZER_WORDSIZE == 64 2177 if (UNLIKELY(internal_sysctlbyname("kern.elf64.aslr.pie_enable", 2178 &aslr_pie, &len, NULL, 0) == -1)) { 2179 // We're making things less 'dramatic' here since 2180 // the OID is not necessarily guaranteed to be here 2181 // just yet regarding FreeBSD release 2182 return; 2183 } 2184 2185 if (aslr_pie > 0) { 2186 Printf("This sanitizer is not compatible with enabled ASLR " 2187 "and binaries compiled with PIE\n"); 2188 Die(); 2189 } 2190 #endif 2191 // there might be 32 bits compat for 64 bits 2192 if (UNLIKELY(internal_sysctlbyname("kern.elf32.aslr.pie_enable", 2193 &aslr_pie, &len, NULL, 0) == -1)) { 2194 return; 2195 } 2196 2197 if (aslr_pie > 0) { 2198 Printf("This sanitizer is not compatible with enabled ASLR " 2199 "and binaries compiled with PIE\n"); 2200 Die(); 2201 } 2202 #else 2203 // Do nothing 2204 #endif 2205 } 2206 2207 void CheckMPROTECT() { 2208 #if SANITIZER_NETBSD 2209 int mib[3]; 2210 int paxflags; 2211 uptr len = sizeof(paxflags); 2212 2213 mib[0] = CTL_PROC; 2214 mib[1] = internal_getpid(); 2215 mib[2] = PROC_PID_PAXFLAGS; 2216 2217 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2218 Printf("sysctl failed\n"); 2219 Die(); 2220 } 2221 2222 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_MPROTECT)) { 2223 Printf("This sanitizer is not compatible with enabled MPROTECT\n"); 2224 Die(); 2225 } 2226 #else 2227 // Do nothing 2228 #endif 2229 } 2230 2231 void CheckNoDeepBind(const char *filename, int flag) { 2232 #ifdef RTLD_DEEPBIND 2233 if (flag & RTLD_DEEPBIND) { 2234 Report( 2235 "You are trying to dlopen a %s shared library with RTLD_DEEPBIND flag" 2236 " which is incompatible with sanitizer runtime " 2237 "(see https://github.com/google/sanitizers/issues/611 for details" 2238 "). If you want to run %s library under sanitizers please remove " 2239 "RTLD_DEEPBIND from dlopen flags.\n", 2240 filename, filename); 2241 Die(); 2242 } 2243 #endif 2244 } 2245 2246 uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding, 2247 uptr *largest_gap_found, 2248 uptr *max_occupied_addr) { 2249 UNREACHABLE("FindAvailableMemoryRange is not available"); 2250 return 0; 2251 } 2252 2253 bool GetRandom(void *buffer, uptr length, bool blocking) { 2254 if (!buffer || !length || length > 256) 2255 return false; 2256 #if SANITIZER_USE_GETENTROPY 2257 uptr rnd = getentropy(buffer, length); 2258 int rverrno = 0; 2259 if (internal_iserror(rnd, &rverrno) && rverrno == EFAULT) 2260 return false; 2261 else if (rnd == 0) 2262 return true; 2263 #endif // SANITIZER_USE_GETENTROPY 2264 2265 #if SANITIZER_USE_GETRANDOM 2266 static atomic_uint8_t skip_getrandom_syscall; 2267 if (!atomic_load_relaxed(&skip_getrandom_syscall)) { 2268 // Up to 256 bytes, getrandom will not be interrupted. 2269 uptr res = internal_syscall(SYSCALL(getrandom), buffer, length, 2270 blocking ? 0 : GRND_NONBLOCK); 2271 int rverrno = 0; 2272 if (internal_iserror(res, &rverrno) && rverrno == ENOSYS) 2273 atomic_store_relaxed(&skip_getrandom_syscall, 1); 2274 else if (res == length) 2275 return true; 2276 } 2277 #endif // SANITIZER_USE_GETRANDOM 2278 // Up to 256 bytes, a read off /dev/urandom will not be interrupted. 2279 // blocking is moot here, O_NONBLOCK has no effect when opening /dev/urandom. 2280 uptr fd = internal_open("/dev/urandom", O_RDONLY); 2281 if (internal_iserror(fd)) 2282 return false; 2283 uptr res = internal_read(fd, buffer, length); 2284 if (internal_iserror(res)) 2285 return false; 2286 internal_close(fd); 2287 return true; 2288 } 2289 2290 } // namespace __sanitizer 2291 2292 #endif 2293