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