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