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_OPENBSD || 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 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#include <asm/stat.h> 42#undef stat 43#endif 44 45#include <dlfcn.h> 46#include <errno.h> 47#include <fcntl.h> 48#include <link.h> 49#include <pthread.h> 50#include <sched.h> 51#include <signal.h> 52#include <sys/mman.h> 53#include <sys/param.h> 54#if !SANITIZER_SOLARIS 55#include <sys/ptrace.h> 56#endif 57#include <sys/resource.h> 58#include <sys/stat.h> 59#include <sys/syscall.h> 60#include <sys/time.h> 61#include <sys/types.h> 62#if !SANITIZER_OPENBSD 63#include <ucontext.h> 64#endif 65#if SANITIZER_OPENBSD 66#include <sys/futex.h> 67#include <sys/sysctl.h> 68#endif 69#include <unistd.h> 70 71#if SANITIZER_LINUX 72#include <sys/utsname.h> 73#endif 74 75#if SANITIZER_LINUX && !SANITIZER_ANDROID 76#include <sys/personality.h> 77#endif 78 79#if SANITIZER_FREEBSD 80#include <sys/exec.h> 81#include <sys/sysctl.h> 82#include <machine/atomic.h> 83extern "C" { 84// <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on 85// FreeBSD 9.2 and 10.0. 86#include <sys/umtx.h> 87} 88#include <sys/thr.h> 89#endif // SANITIZER_FREEBSD 90 91#if SANITIZER_NETBSD 92#include <limits.h> // For NAME_MAX 93#include <sys/sysctl.h> 94#include <sys/exec.h> 95extern struct ps_strings *__ps_strings; 96#endif // SANITIZER_NETBSD 97 98#if SANITIZER_SOLARIS 99#include <stdlib.h> 100#include <thread.h> 101#define environ _environ 102#endif 103 104extern char **environ; 105 106#if SANITIZER_LINUX 107// <linux/time.h> 108struct kernel_timeval { 109 long tv_sec; 110 long tv_usec; 111}; 112 113// <linux/futex.h> is broken on some linux distributions. 114const int FUTEX_WAIT = 0; 115const int FUTEX_WAKE = 1; 116const int FUTEX_PRIVATE_FLAG = 128; 117const int FUTEX_WAIT_PRIVATE = FUTEX_WAIT | FUTEX_PRIVATE_FLAG; 118const int FUTEX_WAKE_PRIVATE = FUTEX_WAKE | FUTEX_PRIVATE_FLAG; 119#endif // SANITIZER_LINUX 120 121// Are we using 32-bit or 64-bit Linux syscalls? 122// x32 (which defines __x86_64__) has SANITIZER_WORDSIZE == 32 123// but it still needs to use 64-bit syscalls. 124#if SANITIZER_LINUX && (defined(__x86_64__) || defined(__powerpc64__) || \ 125 SANITIZER_WORDSIZE == 64) 126# define SANITIZER_LINUX_USES_64BIT_SYSCALLS 1 127#else 128# define SANITIZER_LINUX_USES_64BIT_SYSCALLS 0 129#endif 130 131// Note : FreeBSD had implemented both 132// Linux and OpenBSD apis, available from 133// future 12.x version most likely 134#if SANITIZER_LINUX && defined(__NR_getrandom) 135# if !defined(GRND_NONBLOCK) 136# define GRND_NONBLOCK 1 137# endif 138# define SANITIZER_USE_GETRANDOM 1 139#else 140# define SANITIZER_USE_GETRANDOM 0 141#endif // SANITIZER_LINUX && defined(__NR_getrandom) 142 143#if SANITIZER_OPENBSD 144# define SANITIZER_USE_GETENTROPY 1 145#else 146# if SANITIZER_FREEBSD && __FreeBSD_version >= 1200000 147# define SANITIZER_USE_GETENTROPY 1 148# else 149# define SANITIZER_USE_GETENTROPY 0 150# endif 151#endif // SANITIZER_USE_GETENTROPY 152 153namespace __sanitizer { 154 155#if SANITIZER_LINUX && defined(__x86_64__) 156#include "sanitizer_syscall_linux_x86_64.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 && !SANITIZER_OPENBSD 168uptr 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 && !SANITIZER_OPENBSD 181 182#if !SANITIZER_OPENBSD 183uptr internal_munmap(void *addr, uptr length) { 184 return internal_syscall(SYSCALL(munmap), (uptr)addr, length); 185} 186 187int internal_mprotect(void *addr, uptr length, int prot) { 188 return internal_syscall(SYSCALL(mprotect), (uptr)addr, length, prot); 189} 190#endif 191 192uptr internal_close(fd_t fd) { 193 return internal_syscall(SYSCALL(close), fd); 194} 195 196uptr internal_open(const char *filename, int flags) { 197#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 198 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags); 199#else 200 return internal_syscall(SYSCALL(open), (uptr)filename, flags); 201#endif 202} 203 204uptr internal_open(const char *filename, int flags, u32 mode) { 205#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 206 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags, 207 mode); 208#else 209 return internal_syscall(SYSCALL(open), (uptr)filename, flags, mode); 210#endif 211} 212 213uptr internal_read(fd_t fd, void *buf, uptr count) { 214 sptr res; 215 HANDLE_EINTR(res, 216 (sptr)internal_syscall(SYSCALL(read), fd, (uptr)buf, count)); 217 return res; 218} 219 220uptr internal_write(fd_t fd, const void *buf, uptr count) { 221 sptr res; 222 HANDLE_EINTR(res, 223 (sptr)internal_syscall(SYSCALL(write), fd, (uptr)buf, count)); 224 return res; 225} 226 227uptr internal_ftruncate(fd_t fd, uptr size) { 228 sptr res; 229 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(ftruncate), fd, 230 (OFF_T)size)); 231 return res; 232} 233 234#if !SANITIZER_LINUX_USES_64BIT_SYSCALLS && SANITIZER_LINUX 235static void stat64_to_stat(struct stat64 *in, struct stat *out) { 236 internal_memset(out, 0, sizeof(*out)); 237 out->st_dev = in->st_dev; 238 out->st_ino = in->st_ino; 239 out->st_mode = in->st_mode; 240 out->st_nlink = in->st_nlink; 241 out->st_uid = in->st_uid; 242 out->st_gid = in->st_gid; 243 out->st_rdev = in->st_rdev; 244 out->st_size = in->st_size; 245 out->st_blksize = in->st_blksize; 246 out->st_blocks = in->st_blocks; 247 out->st_atime = in->st_atime; 248 out->st_mtime = in->st_mtime; 249 out->st_ctime = in->st_ctime; 250} 251#endif 252 253#if defined(__mips64) 254// Undefine compatibility macros from <sys/stat.h> 255// so that they would not clash with the kernel_stat 256// st_[a|m|c]time fields 257#undef st_atime 258#undef st_mtime 259#undef st_ctime 260#if defined(SANITIZER_ANDROID) 261// Bionic sys/stat.h defines additional macros 262// for compatibility with the old NDKs and 263// they clash with the kernel_stat structure 264// st_[a|m|c]time_nsec fields. 265#undef st_atime_nsec 266#undef st_mtime_nsec 267#undef st_ctime_nsec 268#endif 269static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) { 270 internal_memset(out, 0, sizeof(*out)); 271 out->st_dev = in->st_dev; 272 out->st_ino = in->st_ino; 273 out->st_mode = in->st_mode; 274 out->st_nlink = in->st_nlink; 275 out->st_uid = in->st_uid; 276 out->st_gid = in->st_gid; 277 out->st_rdev = in->st_rdev; 278 out->st_size = in->st_size; 279 out->st_blksize = in->st_blksize; 280 out->st_blocks = in->st_blocks; 281#if defined(__USE_MISC) || \ 282 defined(__USE_XOPEN2K8) || \ 283 defined(SANITIZER_ANDROID) 284 out->st_atim.tv_sec = in->st_atime; 285 out->st_atim.tv_nsec = in->st_atime_nsec; 286 out->st_mtim.tv_sec = in->st_mtime; 287 out->st_mtim.tv_nsec = in->st_mtime_nsec; 288 out->st_ctim.tv_sec = in->st_ctime; 289 out->st_ctim.tv_nsec = in->st_ctime_nsec; 290#else 291 out->st_atime = in->st_atime; 292 out->st_atimensec = in->st_atime_nsec; 293 out->st_mtime = in->st_mtime; 294 out->st_mtimensec = in->st_mtime_nsec; 295 out->st_ctime = in->st_ctime; 296 out->st_atimensec = in->st_ctime_nsec; 297#endif 298} 299#endif 300 301uptr internal_stat(const char *path, void *buf) { 302#if SANITIZER_FREEBSD || SANITIZER_OPENBSD 303 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 0); 304#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 305 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 306 0); 307#elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 308# if defined(__mips64) 309 // For mips64, stat syscall fills buffer in the format of kernel_stat 310 struct kernel_stat kbuf; 311 int res = internal_syscall(SYSCALL(stat), path, &kbuf); 312 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 313 return res; 314# else 315 return internal_syscall(SYSCALL(stat), (uptr)path, (uptr)buf); 316# endif 317#else 318 struct stat64 buf64; 319 int res = internal_syscall(SYSCALL(stat64), path, &buf64); 320 stat64_to_stat(&buf64, (struct stat *)buf); 321 return res; 322#endif 323} 324 325uptr internal_lstat(const char *path, void *buf) { 326#if SANITIZER_FREEBSD || SANITIZER_OPENBSD 327 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 328 AT_SYMLINK_NOFOLLOW); 329#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 330 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 331 AT_SYMLINK_NOFOLLOW); 332#elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 333# if SANITIZER_MIPS64 334 // For mips64, lstat syscall fills buffer in the format of kernel_stat 335 struct kernel_stat kbuf; 336 int res = internal_syscall(SYSCALL(lstat), path, &kbuf); 337 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 338 return res; 339# else 340 return internal_syscall(SYSCALL(lstat), (uptr)path, (uptr)buf); 341# endif 342#else 343 struct stat64 buf64; 344 int res = internal_syscall(SYSCALL(lstat64), path, &buf64); 345 stat64_to_stat(&buf64, (struct stat *)buf); 346 return res; 347#endif 348} 349 350uptr internal_fstat(fd_t fd, void *buf) { 351#if SANITIZER_FREEBSD || SANITIZER_OPENBSD || \ 352 SANITIZER_LINUX_USES_64BIT_SYSCALLS 353#if SANITIZER_MIPS64 && !SANITIZER_OPENBSD 354 // For mips64, fstat syscall fills buffer in the format of kernel_stat 355 struct kernel_stat kbuf; 356 int res = internal_syscall(SYSCALL(fstat), fd, &kbuf); 357 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 358 return res; 359# else 360 return internal_syscall(SYSCALL(fstat), fd, (uptr)buf); 361# endif 362#else 363 struct stat64 buf64; 364 int res = internal_syscall(SYSCALL(fstat64), fd, &buf64); 365 stat64_to_stat(&buf64, (struct stat *)buf); 366 return res; 367#endif 368} 369 370uptr internal_filesize(fd_t fd) { 371 struct stat st; 372 if (internal_fstat(fd, &st)) 373 return -1; 374 return (uptr)st.st_size; 375} 376 377uptr internal_dup(int oldfd) { 378 return internal_syscall(SYSCALL(dup), oldfd); 379} 380 381uptr internal_dup2(int oldfd, int newfd) { 382#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 383 return internal_syscall(SYSCALL(dup3), oldfd, newfd, 0); 384#else 385 return internal_syscall(SYSCALL(dup2), oldfd, newfd); 386#endif 387} 388 389uptr internal_readlink(const char *path, char *buf, uptr bufsize) { 390#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 391 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD, (uptr)path, (uptr)buf, 392 bufsize); 393#elif SANITIZER_OPENBSD 394 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD, (uptr)path, (uptr)buf, 395 bufsize); 396#else 397 return internal_syscall(SYSCALL(readlink), (uptr)path, (uptr)buf, bufsize); 398#endif 399} 400 401uptr internal_unlink(const char *path) { 402#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS || SANITIZER_OPENBSD 403 return internal_syscall(SYSCALL(unlinkat), AT_FDCWD, (uptr)path, 0); 404#else 405 return internal_syscall(SYSCALL(unlink), (uptr)path); 406#endif 407} 408 409uptr internal_rename(const char *oldpath, const char *newpath) { 410#if defined(__riscv) 411 return internal_syscall(SYSCALL(renameat2), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 412 (uptr)newpath, 0); 413#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS || SANITIZER_OPENBSD 414 return internal_syscall(SYSCALL(renameat), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 415 (uptr)newpath); 416#else 417 return internal_syscall(SYSCALL(rename), (uptr)oldpath, (uptr)newpath); 418#endif 419} 420 421uptr internal_sched_yield() { 422 return internal_syscall(SYSCALL(sched_yield)); 423} 424 425void internal__exit(int exitcode) { 426#if SANITIZER_FREEBSD || SANITIZER_OPENBSD 427 internal_syscall(SYSCALL(exit), exitcode); 428#else 429 internal_syscall(SYSCALL(exit_group), exitcode); 430#endif 431 Die(); // Unreachable. 432} 433 434unsigned int internal_sleep(unsigned int seconds) { 435 struct timespec ts; 436 ts.tv_sec = seconds; 437 ts.tv_nsec = 0; 438 int res = internal_syscall(SYSCALL(nanosleep), &ts, &ts); 439 if (res) return ts.tv_sec; 440 return 0; 441} 442 443uptr internal_execve(const char *filename, char *const argv[], 444 char *const envp[]) { 445 return internal_syscall(SYSCALL(execve), (uptr)filename, (uptr)argv, 446 (uptr)envp); 447} 448#endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD 449 450// ----------------- sanitizer_common.h 451bool FileExists(const char *filename) { 452 if (ShouldMockFailureToOpen(filename)) 453 return false; 454 struct stat st; 455#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 456 if (internal_syscall(SYSCALL(newfstatat), AT_FDCWD, filename, &st, 0)) 457#else 458 if (internal_stat(filename, &st)) 459#endif 460 return false; 461 // Sanity check: filename is a regular file. 462 return S_ISREG(st.st_mode); 463} 464 465#if !SANITIZER_NETBSD 466tid_t GetTid() { 467#if SANITIZER_FREEBSD 468 long Tid; 469 thr_self(&Tid); 470 return Tid; 471#elif SANITIZER_OPENBSD 472 return internal_syscall(SYSCALL(getthrid)); 473#elif SANITIZER_SOLARIS 474 return thr_self(); 475#else 476 return internal_syscall(SYSCALL(gettid)); 477#endif 478} 479 480int TgKill(pid_t pid, tid_t tid, int sig) { 481#if SANITIZER_LINUX 482 return internal_syscall(SYSCALL(tgkill), pid, tid, sig); 483#elif SANITIZER_FREEBSD 484 return internal_syscall(SYSCALL(thr_kill2), pid, tid, sig); 485#elif SANITIZER_OPENBSD 486 (void)pid; 487 return internal_syscall(SYSCALL(thrkill), tid, sig, nullptr); 488#elif SANITIZER_SOLARIS 489 (void)pid; 490 return thr_kill(tid, sig); 491#endif 492} 493#endif 494 495#if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 496u64 NanoTime() { 497#if SANITIZER_FREEBSD || SANITIZER_OPENBSD 498 timeval tv; 499#else 500 kernel_timeval tv; 501#endif 502 internal_memset(&tv, 0, sizeof(tv)); 503 internal_syscall(SYSCALL(gettimeofday), &tv, 0); 504 return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000; 505} 506 507uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) { 508 return internal_syscall(SYSCALL(clock_gettime), clk_id, tp); 509} 510#endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD 511 512// Like getenv, but reads env directly from /proc (on Linux) or parses the 513// 'environ' array (on some others) and does not use libc. This function 514// should be called first inside __asan_init. 515const char *GetEnv(const char *name) { 516#if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_OPENBSD || \ 517 SANITIZER_SOLARIS 518 if (::environ != 0) { 519 uptr NameLen = internal_strlen(name); 520 for (char **Env = ::environ; *Env != 0; Env++) { 521 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=') 522 return (*Env) + NameLen + 1; 523 } 524 } 525 return 0; // Not found. 526#elif SANITIZER_LINUX 527 static char *environ; 528 static uptr len; 529 static bool inited; 530 if (!inited) { 531 inited = true; 532 uptr environ_size; 533 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len)) 534 environ = nullptr; 535 } 536 if (!environ || len == 0) return nullptr; 537 uptr namelen = internal_strlen(name); 538 const char *p = environ; 539 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer 540 // proc file has the format NAME=value\0NAME=value\0NAME=value\0... 541 const char* endp = 542 (char*)internal_memchr(p, '\0', len - (p - environ)); 543 if (!endp) // this entry isn't NUL terminated 544 return nullptr; 545 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match. 546 return p + namelen + 1; // point after = 547 p = endp + 1; 548 } 549 return nullptr; // Not found. 550#else 551#error "Unsupported platform" 552#endif 553} 554 555#if !SANITIZER_FREEBSD && !SANITIZER_NETBSD && !SANITIZER_OPENBSD 556extern "C" { 557SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end; 558} 559#endif 560 561#if !SANITIZER_GO && !SANITIZER_FREEBSD && !SANITIZER_NETBSD && \ 562 !SANITIZER_OPENBSD 563static void ReadNullSepFileToArray(const char *path, char ***arr, 564 int arr_size) { 565 char *buff; 566 uptr buff_size; 567 uptr buff_len; 568 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray"); 569 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) { 570 (*arr)[0] = nullptr; 571 return; 572 } 573 (*arr)[0] = buff; 574 int count, i; 575 for (count = 1, i = 1; ; i++) { 576 if (buff[i] == 0) { 577 if (buff[i+1] == 0) break; 578 (*arr)[count] = &buff[i+1]; 579 CHECK_LE(count, arr_size - 1); // FIXME: make this more flexible. 580 count++; 581 } 582 } 583 (*arr)[count] = nullptr; 584} 585#endif 586 587#if !SANITIZER_OPENBSD 588static void GetArgsAndEnv(char ***argv, char ***envp) { 589#if SANITIZER_FREEBSD 590 // On FreeBSD, retrieving the argument and environment arrays is done via the 591 // kern.ps_strings sysctl, which returns a pointer to a structure containing 592 // this information. See also <sys/exec.h>. 593 ps_strings *pss; 594 uptr sz = sizeof(pss); 595 if (internal_sysctlbyname("kern.ps_strings", &pss, &sz, NULL, 0) == -1) { 596 Printf("sysctl kern.ps_strings failed\n"); 597 Die(); 598 } 599 *argv = pss->ps_argvstr; 600 *envp = pss->ps_envstr; 601#elif SANITIZER_NETBSD 602 *argv = __ps_strings->ps_argvstr; 603 *envp = __ps_strings->ps_envstr; 604#else // SANITIZER_FREEBSD 605#if !SANITIZER_GO 606 if (&__libc_stack_end) { 607#endif // !SANITIZER_GO 608 uptr* stack_end = (uptr*)__libc_stack_end; 609 int argc = *stack_end; 610 *argv = (char**)(stack_end + 1); 611 *envp = (char**)(stack_end + argc + 2); 612#if !SANITIZER_GO 613 } else { 614 static const int kMaxArgv = 2000, kMaxEnvp = 2000; 615 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv); 616 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp); 617 } 618#endif // !SANITIZER_GO 619#endif // SANITIZER_FREEBSD 620} 621 622char **GetArgv() { 623 char **argv, **envp; 624 GetArgsAndEnv(&argv, &envp); 625 return argv; 626} 627 628char **GetEnviron() { 629 char **argv, **envp; 630 GetArgsAndEnv(&argv, &envp); 631 return envp; 632} 633 634#endif // !SANITIZER_OPENBSD 635 636#if !SANITIZER_SOLARIS 637enum MutexState { 638 MtxUnlocked = 0, 639 MtxLocked = 1, 640 MtxSleeping = 2 641}; 642 643BlockingMutex::BlockingMutex() { 644 internal_memset(this, 0, sizeof(*this)); 645} 646 647void BlockingMutex::Lock() { 648 CHECK_EQ(owner_, 0); 649 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 650 if (atomic_exchange(m, MtxLocked, memory_order_acquire) == MtxUnlocked) 651 return; 652 while (atomic_exchange(m, MtxSleeping, memory_order_acquire) != MtxUnlocked) { 653#if SANITIZER_FREEBSD 654 _umtx_op(m, UMTX_OP_WAIT_UINT, MtxSleeping, 0, 0); 655#elif SANITIZER_NETBSD 656 sched_yield(); /* No userspace futex-like synchronization */ 657#else 658 internal_syscall(SYSCALL(futex), (uptr)m, FUTEX_WAIT_PRIVATE, MtxSleeping, 659 0, 0, 0); 660#endif 661 } 662} 663 664void BlockingMutex::Unlock() { 665 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 666 u32 v = atomic_exchange(m, MtxUnlocked, memory_order_release); 667 CHECK_NE(v, MtxUnlocked); 668 if (v == MtxSleeping) { 669#if SANITIZER_FREEBSD 670 _umtx_op(m, UMTX_OP_WAKE, 1, 0, 0); 671#elif SANITIZER_NETBSD 672 /* No userspace futex-like synchronization */ 673#else 674 internal_syscall(SYSCALL(futex), (uptr)m, FUTEX_WAKE_PRIVATE, 1, 0, 0, 0); 675#endif 676 } 677} 678 679void BlockingMutex::CheckLocked() { 680 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 681 CHECK_NE(MtxUnlocked, atomic_load(m, memory_order_relaxed)); 682} 683#endif // !SANITIZER_SOLARIS 684 685// ----------------- sanitizer_linux.h 686// The actual size of this structure is specified by d_reclen. 687// Note that getdents64 uses a different structure format. We only provide the 688// 32-bit syscall here. 689#if SANITIZER_NETBSD 690// Not used 691#elif SANITIZER_OPENBSD 692// struct dirent is different for Linux and us. At this moment, we use only 693// d_fileno (Linux call this d_ino), d_reclen, and d_name. 694struct linux_dirent { 695 u64 d_ino; // d_fileno 696 u16 d_reclen; 697 u16 d_namlen; // not used 698 u8 d_type; // not used 699 char d_name[NAME_MAX + 1]; 700}; 701#else 702struct linux_dirent { 703#if SANITIZER_X32 || defined(__aarch64__) 704 u64 d_ino; 705 u64 d_off; 706#else 707 unsigned long d_ino; 708 unsigned long d_off; 709#endif 710 unsigned short d_reclen; 711#ifdef __aarch64__ 712 unsigned char d_type; 713#endif 714 char d_name[256]; 715}; 716#endif 717 718#if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 719// Syscall wrappers. 720uptr internal_ptrace(int request, int pid, void *addr, void *data) { 721 return internal_syscall(SYSCALL(ptrace), request, pid, (uptr)addr, 722 (uptr)data); 723} 724 725uptr internal_waitpid(int pid, int *status, int options) { 726 return internal_syscall(SYSCALL(wait4), pid, (uptr)status, options, 727 0 /* rusage */); 728} 729 730uptr internal_getpid() { 731 return internal_syscall(SYSCALL(getpid)); 732} 733 734uptr internal_getppid() { 735 return internal_syscall(SYSCALL(getppid)); 736} 737 738uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) { 739#if SANITIZER_FREEBSD 740 return internal_syscall(SYSCALL(getdirentries), fd, (uptr)dirp, count, NULL); 741#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 742 return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count); 743#else 744 return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count); 745#endif 746} 747 748uptr internal_lseek(fd_t fd, OFF_T offset, int whence) { 749 return internal_syscall(SYSCALL(lseek), fd, offset, whence); 750} 751 752#if SANITIZER_LINUX 753uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) { 754 return internal_syscall(SYSCALL(prctl), option, arg2, arg3, arg4, arg5); 755} 756#endif 757 758uptr internal_sigaltstack(const void *ss, void *oss) { 759 return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss); 760} 761 762int internal_fork() { 763#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 764 return internal_syscall(SYSCALL(clone), SIGCHLD, 0); 765#else 766 return internal_syscall(SYSCALL(fork)); 767#endif 768} 769 770#if SANITIZER_FREEBSD || SANITIZER_OPENBSD 771int internal_sysctl(const int *name, unsigned int namelen, void *oldp, 772 uptr *oldlenp, const void *newp, uptr newlen) { 773#if SANITIZER_OPENBSD 774 return sysctl(name, namelen, oldp, (size_t *)oldlenp, (void *)newp, 775 (size_t)newlen); 776#else 777 return internal_syscall(SYSCALL(__sysctl), name, namelen, oldp, 778 (size_t *)oldlenp, newp, (size_t)newlen); 779#endif 780} 781 782#if SANITIZER_FREEBSD 783int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp, 784 const void *newp, uptr newlen) { 785 static decltype(sysctlbyname) *real = nullptr; 786 if (!real) 787 real = (decltype(sysctlbyname) *)dlsym(RTLD_NEXT, "sysctlbyname"); 788 CHECK(real); 789 return real(sname, oldp, (size_t *)oldlenp, newp, (size_t)newlen); 790} 791#endif 792#endif 793 794#if SANITIZER_LINUX 795#define SA_RESTORER 0x04000000 796// Doesn't set sa_restorer if the caller did not set it, so use with caution 797//(see below). 798int internal_sigaction_norestorer(int signum, const void *act, void *oldact) { 799 __sanitizer_kernel_sigaction_t k_act, k_oldact; 800 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t)); 801 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t)); 802 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act; 803 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact; 804 if (u_act) { 805 k_act.handler = u_act->handler; 806 k_act.sigaction = u_act->sigaction; 807 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask, 808 sizeof(__sanitizer_kernel_sigset_t)); 809 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL). 810 k_act.sa_flags = u_act->sa_flags | SA_RESTORER; 811 // FIXME: most often sa_restorer is unset, however the kernel requires it 812 // to point to a valid signal restorer that calls the rt_sigreturn syscall. 813 // If sa_restorer passed to the kernel is NULL, the program may crash upon 814 // signal delivery or fail to unwind the stack in the signal handler. 815 // libc implementation of sigaction() passes its own restorer to 816 // rt_sigaction, so we need to do the same (we'll need to reimplement the 817 // restorers; for x86_64 the restorer address can be obtained from 818 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact). 819#if !SANITIZER_ANDROID || !SANITIZER_MIPS32 820 k_act.sa_restorer = u_act->sa_restorer; 821#endif 822 } 823 824 uptr result = internal_syscall(SYSCALL(rt_sigaction), (uptr)signum, 825 (uptr)(u_act ? &k_act : nullptr), 826 (uptr)(u_oldact ? &k_oldact : nullptr), 827 (uptr)sizeof(__sanitizer_kernel_sigset_t)); 828 829 if ((result == 0) && u_oldact) { 830 u_oldact->handler = k_oldact.handler; 831 u_oldact->sigaction = k_oldact.sigaction; 832 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask, 833 sizeof(__sanitizer_kernel_sigset_t)); 834 u_oldact->sa_flags = k_oldact.sa_flags; 835#if !SANITIZER_ANDROID || !SANITIZER_MIPS32 836 u_oldact->sa_restorer = k_oldact.sa_restorer; 837#endif 838 } 839 return result; 840} 841#endif // SANITIZER_LINUX 842 843uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set, 844 __sanitizer_sigset_t *oldset) { 845#if SANITIZER_FREEBSD || SANITIZER_OPENBSD 846 return internal_syscall(SYSCALL(sigprocmask), how, set, oldset); 847#else 848 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 849 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset; 850 return internal_syscall(SYSCALL(rt_sigprocmask), (uptr)how, 851 (uptr)&k_set->sig[0], (uptr)&k_oldset->sig[0], 852 sizeof(__sanitizer_kernel_sigset_t)); 853#endif 854} 855 856void internal_sigfillset(__sanitizer_sigset_t *set) { 857 internal_memset(set, 0xff, sizeof(*set)); 858} 859 860void internal_sigemptyset(__sanitizer_sigset_t *set) { 861 internal_memset(set, 0, sizeof(*set)); 862} 863 864#if SANITIZER_LINUX 865void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 866 signum -= 1; 867 CHECK_GE(signum, 0); 868 CHECK_LT(signum, sizeof(*set) * 8); 869 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 870 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 871 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 872 k_set->sig[idx] &= ~(1 << bit); 873} 874 875bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 876 signum -= 1; 877 CHECK_GE(signum, 0); 878 CHECK_LT(signum, sizeof(*set) * 8); 879 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 880 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 881 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 882 return k_set->sig[idx] & (1 << bit); 883} 884#elif SANITIZER_FREEBSD 885void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 886 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 887 sigdelset(rset, signum); 888} 889 890bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 891 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 892 return sigismember(rset, signum); 893} 894#endif 895#endif // !SANITIZER_SOLARIS 896 897#if !SANITIZER_NETBSD 898// ThreadLister implementation. 899ThreadLister::ThreadLister(pid_t pid) : pid_(pid), buffer_(4096) { 900 char task_directory_path[80]; 901 internal_snprintf(task_directory_path, sizeof(task_directory_path), 902 "/proc/%d/task/", pid); 903 descriptor_ = internal_open(task_directory_path, O_RDONLY | O_DIRECTORY); 904 if (internal_iserror(descriptor_)) { 905 Report("Can't open /proc/%d/task for reading.\n", pid); 906 } 907} 908 909ThreadLister::Result ThreadLister::ListThreads( 910 InternalMmapVector<tid_t> *threads) { 911 if (internal_iserror(descriptor_)) 912 return Error; 913 internal_lseek(descriptor_, 0, SEEK_SET); 914 threads->clear(); 915 916 Result result = Ok; 917 for (bool first_read = true;; first_read = false) { 918 // Resize to max capacity if it was downsized by IsAlive. 919 buffer_.resize(buffer_.capacity()); 920 CHECK_GE(buffer_.size(), 4096); 921 uptr read = internal_getdents( 922 descriptor_, (struct linux_dirent *)buffer_.data(), buffer_.size()); 923 if (!read) 924 return result; 925 if (internal_iserror(read)) { 926 Report("Can't read directory entries from /proc/%d/task.\n", pid_); 927 return Error; 928 } 929 930 for (uptr begin = (uptr)buffer_.data(), end = begin + read; begin < end;) { 931 struct linux_dirent *entry = (struct linux_dirent *)begin; 932 begin += entry->d_reclen; 933 if (entry->d_ino == 1) { 934 // Inode 1 is for bad blocks and also can be a reason for early return. 935 // Should be emitted if kernel tried to output terminating thread. 936 // See proc_task_readdir implementation in Linux. 937 result = Incomplete; 938 } 939 if (entry->d_ino && *entry->d_name >= '0' && *entry->d_name <= '9') 940 threads->push_back(internal_atoll(entry->d_name)); 941 } 942 943 // Now we are going to detect short-read or early EOF. In such cases Linux 944 // can return inconsistent list with missing alive threads. 945 // Code will just remember that the list can be incomplete but it will 946 // continue reads to return as much as possible. 947 if (!first_read) { 948 // The first one was a short-read by definition. 949 result = Incomplete; 950 } else if (read > buffer_.size() - 1024) { 951 // Read was close to the buffer size. So double the size and assume the 952 // worst. 953 buffer_.resize(buffer_.size() * 2); 954 result = Incomplete; 955 } else if (!threads->empty() && !IsAlive(threads->back())) { 956 // Maybe Linux early returned from read on terminated thread (!pid_alive) 957 // and failed to restore read position. 958 // See next_tid and proc_task_instantiate in Linux. 959 result = Incomplete; 960 } 961 } 962} 963 964bool ThreadLister::IsAlive(int tid) { 965 // /proc/%d/task/%d/status uses same call to detect alive threads as 966 // proc_task_readdir. See task_state implementation in Linux. 967 char path[80]; 968 internal_snprintf(path, sizeof(path), "/proc/%d/task/%d/status", pid_, tid); 969 if (!ReadFileToVector(path, &buffer_) || buffer_.empty()) 970 return false; 971 buffer_.push_back(0); 972 static const char kPrefix[] = "\nPPid:"; 973 const char *field = internal_strstr(buffer_.data(), kPrefix); 974 if (!field) 975 return false; 976 field += internal_strlen(kPrefix); 977 return (int)internal_atoll(field) != 0; 978} 979 980ThreadLister::~ThreadLister() { 981 if (!internal_iserror(descriptor_)) 982 internal_close(descriptor_); 983} 984#endif 985 986#if SANITIZER_WORDSIZE == 32 987// Take care of unusable kernel area in top gigabyte. 988static uptr GetKernelAreaSize() { 989#if SANITIZER_LINUX && !SANITIZER_X32 990 const uptr gbyte = 1UL << 30; 991 992 // Firstly check if there are writable segments 993 // mapped to top gigabyte (e.g. stack). 994 MemoryMappingLayout proc_maps(/*cache_enabled*/true); 995 if (proc_maps.Error()) 996 return 0; 997 MemoryMappedSegment segment; 998 while (proc_maps.Next(&segment)) { 999 if ((segment.end >= 3 * gbyte) && segment.IsWritable()) return 0; 1000 } 1001 1002#if !SANITIZER_ANDROID 1003 // Even if nothing is mapped, top Gb may still be accessible 1004 // if we are running on 64-bit kernel. 1005 // Uname may report misleading results if personality type 1006 // is modified (e.g. under schroot) so check this as well. 1007 struct utsname uname_info; 1008 int pers = personality(0xffffffffUL); 1009 if (!(pers & PER_MASK) 1010 && uname(&uname_info) == 0 1011 && internal_strstr(uname_info.machine, "64")) 1012 return 0; 1013#endif // SANITIZER_ANDROID 1014 1015 // Top gigabyte is reserved for kernel. 1016 return gbyte; 1017#else 1018 return 0; 1019#endif // SANITIZER_LINUX && !SANITIZER_X32 1020} 1021#endif // SANITIZER_WORDSIZE == 32 1022 1023uptr GetMaxVirtualAddress() { 1024#if (SANITIZER_NETBSD || SANITIZER_OPENBSD) && defined(__x86_64__) 1025 return 0x7f7ffffff000ULL; // (0x00007f8000000000 - PAGE_SIZE) 1026#elif SANITIZER_WORDSIZE == 64 1027# if defined(__powerpc64__) || defined(__aarch64__) 1028 // On PowerPC64 we have two different address space layouts: 44- and 46-bit. 1029 // We somehow need to figure out which one we are using now and choose 1030 // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL. 1031 // Note that with 'ulimit -s unlimited' the stack is moved away from the top 1032 // of the address space, so simply checking the stack address is not enough. 1033 // This should (does) work for both PowerPC64 Endian modes. 1034 // Similarly, aarch64 has multiple address space layouts: 39, 42 and 47-bit. 1035 return (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1)) - 1; 1036# elif defined(__mips64) 1037 return (1ULL << 40) - 1; // 0x000000ffffffffffUL; 1038# elif defined(__s390x__) 1039 return (1ULL << 53) - 1; // 0x001fffffffffffffUL; 1040#elif defined(__sparc__) 1041 return ~(uptr)0; 1042# else 1043 return (1ULL << 47) - 1; // 0x00007fffffffffffUL; 1044# endif 1045#else // SANITIZER_WORDSIZE == 32 1046# if defined(__s390__) 1047 return (1ULL << 31) - 1; // 0x7fffffff; 1048# else 1049 return (1ULL << 32) - 1; // 0xffffffff; 1050# endif 1051#endif // SANITIZER_WORDSIZE 1052} 1053 1054uptr GetMaxUserVirtualAddress() { 1055 uptr addr = GetMaxVirtualAddress(); 1056#if SANITIZER_WORDSIZE == 32 && !defined(__s390__) 1057 if (!common_flags()->full_address_space) 1058 addr -= GetKernelAreaSize(); 1059 CHECK_LT(reinterpret_cast<uptr>(&addr), addr); 1060#endif 1061 return addr; 1062} 1063 1064#if !SANITIZER_ANDROID 1065uptr GetPageSize() { 1066#if SANITIZER_LINUX && (defined(__x86_64__) || defined(__i386__)) 1067 return EXEC_PAGESIZE; 1068#elif SANITIZER_FREEBSD || SANITIZER_NETBSD 1069// Use sysctl as sysconf can trigger interceptors internally. 1070 int pz = 0; 1071 uptr pzl = sizeof(pz); 1072 int mib[2] = {CTL_HW, HW_PAGESIZE}; 1073 int rv = internal_sysctl(mib, 2, &pz, &pzl, nullptr, 0); 1074 CHECK_EQ(rv, 0); 1075 return (uptr)pz; 1076#elif SANITIZER_USE_GETAUXVAL 1077 return getauxval(AT_PAGESZ); 1078#else 1079 return sysconf(_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy. 1080#endif 1081} 1082#endif // !SANITIZER_ANDROID 1083 1084#if !SANITIZER_OPENBSD 1085uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) { 1086#if SANITIZER_SOLARIS 1087 const char *default_module_name = getexecname(); 1088 CHECK_NE(default_module_name, NULL); 1089 return internal_snprintf(buf, buf_len, "%s", default_module_name); 1090#else 1091#if SANITIZER_FREEBSD || SANITIZER_NETBSD 1092#if SANITIZER_FREEBSD 1093 const int Mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1}; 1094#else 1095 const int Mib[4] = {CTL_KERN, KERN_PROC_ARGS, -1, KERN_PROC_PATHNAME}; 1096#endif 1097 const char *default_module_name = "kern.proc.pathname"; 1098 uptr Size = buf_len; 1099 bool IsErr = 1100 (internal_sysctl(Mib, ARRAY_SIZE(Mib), buf, &Size, NULL, 0) != 0); 1101 int readlink_error = IsErr ? errno : 0; 1102 uptr module_name_len = Size; 1103#else 1104 const char *default_module_name = "/proc/self/exe"; 1105 uptr module_name_len = internal_readlink( 1106 default_module_name, buf, buf_len); 1107 int readlink_error; 1108 bool IsErr = internal_iserror(module_name_len, &readlink_error); 1109#endif // SANITIZER_SOLARIS 1110 if (IsErr) { 1111 // We can't read binary name for some reason, assume it's unknown. 1112 Report("WARNING: reading executable name failed with errno %d, " 1113 "some stack frames may not be symbolized\n", readlink_error); 1114 module_name_len = internal_snprintf(buf, buf_len, "%s", 1115 default_module_name); 1116 CHECK_LT(module_name_len, buf_len); 1117 } 1118 return module_name_len; 1119#endif 1120} 1121#endif // !SANITIZER_OPENBSD 1122 1123uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) { 1124#if SANITIZER_LINUX 1125 char *tmpbuf; 1126 uptr tmpsize; 1127 uptr tmplen; 1128 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen, 1129 1024 * 1024)) { 1130 internal_strncpy(buf, tmpbuf, buf_len); 1131 UnmapOrDie(tmpbuf, tmpsize); 1132 return internal_strlen(buf); 1133 } 1134#endif 1135 return ReadBinaryName(buf, buf_len); 1136} 1137 1138// Match full names of the form /path/to/base_name{-,.}* 1139bool LibraryNameIs(const char *full_name, const char *base_name) { 1140 const char *name = full_name; 1141 // Strip path. 1142 while (*name != '\0') name++; 1143 while (name > full_name && *name != '/') name--; 1144 if (*name == '/') name++; 1145 uptr base_name_length = internal_strlen(base_name); 1146 if (internal_strncmp(name, base_name, base_name_length)) return false; 1147 return (name[base_name_length] == '-' || name[base_name_length] == '.'); 1148} 1149 1150#if !SANITIZER_ANDROID 1151// Call cb for each region mapped by map. 1152void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) { 1153 CHECK_NE(map, nullptr); 1154#if !SANITIZER_FREEBSD && !SANITIZER_OPENBSD 1155 typedef ElfW(Phdr) Elf_Phdr; 1156 typedef ElfW(Ehdr) Elf_Ehdr; 1157#endif // !SANITIZER_FREEBSD && !SANITIZER_OPENBSD 1158 char *base = (char *)map->l_addr; 1159 Elf_Ehdr *ehdr = (Elf_Ehdr *)base; 1160 char *phdrs = base + ehdr->e_phoff; 1161 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize; 1162 1163 // Find the segment with the minimum base so we can "relocate" the p_vaddr 1164 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC 1165 // objects have a non-zero base. 1166 uptr preferred_base = (uptr)-1; 1167 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1168 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1169 if (phdr->p_type == PT_LOAD && preferred_base > (uptr)phdr->p_vaddr) 1170 preferred_base = (uptr)phdr->p_vaddr; 1171 } 1172 1173 // Compute the delta from the real base to get a relocation delta. 1174 sptr delta = (uptr)base - preferred_base; 1175 // Now we can figure out what the loader really mapped. 1176 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1177 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1178 if (phdr->p_type == PT_LOAD) { 1179 uptr seg_start = phdr->p_vaddr + delta; 1180 uptr seg_end = seg_start + phdr->p_memsz; 1181 // None of these values are aligned. We consider the ragged edges of the 1182 // load command as defined, since they are mapped from the file. 1183 seg_start = RoundDownTo(seg_start, GetPageSizeCached()); 1184 seg_end = RoundUpTo(seg_end, GetPageSizeCached()); 1185 cb((void *)seg_start, seg_end - seg_start); 1186 } 1187 } 1188} 1189#endif 1190 1191#if defined(__x86_64__) && SANITIZER_LINUX 1192// We cannot use glibc's clone wrapper, because it messes with the child 1193// task's TLS. It writes the PID and TID of the child task to its thread 1194// descriptor, but in our case the child task shares the thread descriptor with 1195// the parent (because we don't know how to allocate a new thread 1196// descriptor to keep glibc happy). So the stock version of clone(), when 1197// used with CLONE_VM, would end up corrupting the parent's thread descriptor. 1198uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1199 int *parent_tidptr, void *newtls, int *child_tidptr) { 1200 long long res; 1201 if (!fn || !child_stack) 1202 return -EINVAL; 1203 CHECK_EQ(0, (uptr)child_stack % 16); 1204 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1205 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1206 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1207 register void *r8 __asm__("r8") = newtls; 1208 register int *r10 __asm__("r10") = child_tidptr; 1209 __asm__ __volatile__( 1210 /* %rax = syscall(%rax = SYSCALL(clone), 1211 * %rdi = flags, 1212 * %rsi = child_stack, 1213 * %rdx = parent_tidptr, 1214 * %r8 = new_tls, 1215 * %r10 = child_tidptr) 1216 */ 1217 "syscall\n" 1218 1219 /* if (%rax != 0) 1220 * return; 1221 */ 1222 "testq %%rax,%%rax\n" 1223 "jnz 1f\n" 1224 1225 /* In the child. Terminate unwind chain. */ 1226 // XXX: We should also terminate the CFI unwind chain 1227 // here. Unfortunately clang 3.2 doesn't support the 1228 // necessary CFI directives, so we skip that part. 1229 "xorq %%rbp,%%rbp\n" 1230 1231 /* Call "fn(arg)". */ 1232 "popq %%rax\n" 1233 "popq %%rdi\n" 1234 "call *%%rax\n" 1235 1236 /* Call _exit(%rax). */ 1237 "movq %%rax,%%rdi\n" 1238 "movq %2,%%rax\n" 1239 "syscall\n" 1240 1241 /* Return to parent. */ 1242 "1:\n" 1243 : "=a" (res) 1244 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1245 "S"(child_stack), 1246 "D"(flags), 1247 "d"(parent_tidptr), 1248 "r"(r8), 1249 "r"(r10) 1250 : "memory", "r11", "rcx"); 1251 return res; 1252} 1253#elif defined(__mips__) 1254uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1255 int *parent_tidptr, void *newtls, int *child_tidptr) { 1256 long long res; 1257 if (!fn || !child_stack) 1258 return -EINVAL; 1259 CHECK_EQ(0, (uptr)child_stack % 16); 1260 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1261 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1262 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1263 register void *a3 __asm__("$7") = newtls; 1264 register int *a4 __asm__("$8") = child_tidptr; 1265 // We don't have proper CFI directives here because it requires alot of code 1266 // for very marginal benefits. 1267 __asm__ __volatile__( 1268 /* $v0 = syscall($v0 = __NR_clone, 1269 * $a0 = flags, 1270 * $a1 = child_stack, 1271 * $a2 = parent_tidptr, 1272 * $a3 = new_tls, 1273 * $a4 = child_tidptr) 1274 */ 1275 ".cprestore 16;\n" 1276 "move $4,%1;\n" 1277 "move $5,%2;\n" 1278 "move $6,%3;\n" 1279 "move $7,%4;\n" 1280 /* Store the fifth argument on stack 1281 * if we are using 32-bit abi. 1282 */ 1283#if SANITIZER_WORDSIZE == 32 1284 "lw %5,16($29);\n" 1285#else 1286 "move $8,%5;\n" 1287#endif 1288 "li $2,%6;\n" 1289 "syscall;\n" 1290 1291 /* if ($v0 != 0) 1292 * return; 1293 */ 1294 "bnez $2,1f;\n" 1295 1296 /* Call "fn(arg)". */ 1297#if SANITIZER_WORDSIZE == 32 1298#ifdef __BIG_ENDIAN__ 1299 "lw $25,4($29);\n" 1300 "lw $4,12($29);\n" 1301#else 1302 "lw $25,0($29);\n" 1303 "lw $4,8($29);\n" 1304#endif 1305#else 1306 "ld $25,0($29);\n" 1307 "ld $4,8($29);\n" 1308#endif 1309 "jal $25;\n" 1310 1311 /* Call _exit($v0). */ 1312 "move $4,$2;\n" 1313 "li $2,%7;\n" 1314 "syscall;\n" 1315 1316 /* Return to parent. */ 1317 "1:\n" 1318 : "=r" (res) 1319 : "r"(flags), 1320 "r"(child_stack), 1321 "r"(parent_tidptr), 1322 "r"(a3), 1323 "r"(a4), 1324 "i"(__NR_clone), 1325 "i"(__NR_exit) 1326 : "memory", "$29" ); 1327 return res; 1328} 1329#elif defined(__aarch64__) 1330uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1331 int *parent_tidptr, void *newtls, int *child_tidptr) { 1332 long long res; 1333 if (!fn || !child_stack) 1334 return -EINVAL; 1335 CHECK_EQ(0, (uptr)child_stack % 16); 1336 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1337 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1338 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1339 1340 register int (*__fn)(void *) __asm__("x0") = fn; 1341 register void *__stack __asm__("x1") = child_stack; 1342 register int __flags __asm__("x2") = flags; 1343 register void *__arg __asm__("x3") = arg; 1344 register int *__ptid __asm__("x4") = parent_tidptr; 1345 register void *__tls __asm__("x5") = newtls; 1346 register int *__ctid __asm__("x6") = child_tidptr; 1347 1348 __asm__ __volatile__( 1349 "mov x0,x2\n" /* flags */ 1350 "mov x2,x4\n" /* ptid */ 1351 "mov x3,x5\n" /* tls */ 1352 "mov x4,x6\n" /* ctid */ 1353 "mov x8,%9\n" /* clone */ 1354 1355 "svc 0x0\n" 1356 1357 /* if (%r0 != 0) 1358 * return %r0; 1359 */ 1360 "cmp x0, #0\n" 1361 "bne 1f\n" 1362 1363 /* In the child, now. Call "fn(arg)". */ 1364 "ldp x1, x0, [sp], #16\n" 1365 "blr x1\n" 1366 1367 /* Call _exit(%r0). */ 1368 "mov x8, %10\n" 1369 "svc 0x0\n" 1370 "1:\n" 1371 1372 : "=r" (res) 1373 : "i"(-EINVAL), 1374 "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg), 1375 "r"(__ptid), "r"(__tls), "r"(__ctid), 1376 "i"(__NR_clone), "i"(__NR_exit) 1377 : "x30", "memory"); 1378 return res; 1379} 1380#elif defined(__powerpc64__) 1381uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1382 int *parent_tidptr, void *newtls, int *child_tidptr) { 1383 long long res; 1384// Stack frame structure. 1385#if SANITIZER_PPC64V1 1386// Back chain == 0 (SP + 112) 1387// Frame (112 bytes): 1388// Parameter save area (SP + 48), 8 doublewords 1389// TOC save area (SP + 40) 1390// Link editor doubleword (SP + 32) 1391// Compiler doubleword (SP + 24) 1392// LR save area (SP + 16) 1393// CR save area (SP + 8) 1394// Back chain (SP + 0) 1395# define FRAME_SIZE 112 1396# define FRAME_TOC_SAVE_OFFSET 40 1397#elif SANITIZER_PPC64V2 1398// Back chain == 0 (SP + 32) 1399// Frame (32 bytes): 1400// TOC save area (SP + 24) 1401// LR save area (SP + 16) 1402// CR save area (SP + 8) 1403// Back chain (SP + 0) 1404# define FRAME_SIZE 32 1405# define FRAME_TOC_SAVE_OFFSET 24 1406#else 1407# error "Unsupported PPC64 ABI" 1408#endif 1409 if (!fn || !child_stack) 1410 return -EINVAL; 1411 CHECK_EQ(0, (uptr)child_stack % 16); 1412 1413 register int (*__fn)(void *) __asm__("r3") = fn; 1414 register void *__cstack __asm__("r4") = child_stack; 1415 register int __flags __asm__("r5") = flags; 1416 register void *__arg __asm__("r6") = arg; 1417 register int *__ptidptr __asm__("r7") = parent_tidptr; 1418 register void *__newtls __asm__("r8") = newtls; 1419 register int *__ctidptr __asm__("r9") = child_tidptr; 1420 1421 __asm__ __volatile__( 1422 /* fn and arg are saved across the syscall */ 1423 "mr 28, %5\n\t" 1424 "mr 27, %8\n\t" 1425 1426 /* syscall 1427 r0 == __NR_clone 1428 r3 == flags 1429 r4 == child_stack 1430 r5 == parent_tidptr 1431 r6 == newtls 1432 r7 == child_tidptr */ 1433 "mr 3, %7\n\t" 1434 "mr 5, %9\n\t" 1435 "mr 6, %10\n\t" 1436 "mr 7, %11\n\t" 1437 "li 0, %3\n\t" 1438 "sc\n\t" 1439 1440 /* Test if syscall was successful */ 1441 "cmpdi cr1, 3, 0\n\t" 1442 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t" 1443 "bne- cr1, 1f\n\t" 1444 1445 /* Set up stack frame */ 1446 "li 29, 0\n\t" 1447 "stdu 29, -8(1)\n\t" 1448 "stdu 1, -%12(1)\n\t" 1449 /* Do the function call */ 1450 "std 2, %13(1)\n\t" 1451#if SANITIZER_PPC64V1 1452 "ld 0, 0(28)\n\t" 1453 "ld 2, 8(28)\n\t" 1454 "mtctr 0\n\t" 1455#elif SANITIZER_PPC64V2 1456 "mr 12, 28\n\t" 1457 "mtctr 12\n\t" 1458#else 1459# error "Unsupported PPC64 ABI" 1460#endif 1461 "mr 3, 27\n\t" 1462 "bctrl\n\t" 1463 "ld 2, %13(1)\n\t" 1464 1465 /* Call _exit(r3) */ 1466 "li 0, %4\n\t" 1467 "sc\n\t" 1468 1469 /* Return to parent */ 1470 "1:\n\t" 1471 "mr %0, 3\n\t" 1472 : "=r" (res) 1473 : "0" (-1), 1474 "i" (EINVAL), 1475 "i" (__NR_clone), 1476 "i" (__NR_exit), 1477 "r" (__fn), 1478 "r" (__cstack), 1479 "r" (__flags), 1480 "r" (__arg), 1481 "r" (__ptidptr), 1482 "r" (__newtls), 1483 "r" (__ctidptr), 1484 "i" (FRAME_SIZE), 1485 "i" (FRAME_TOC_SAVE_OFFSET) 1486 : "cr0", "cr1", "memory", "ctr", "r0", "r27", "r28", "r29"); 1487 return res; 1488} 1489#elif defined(__i386__) && SANITIZER_LINUX 1490uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1491 int *parent_tidptr, void *newtls, int *child_tidptr) { 1492 int res; 1493 if (!fn || !child_stack) 1494 return -EINVAL; 1495 CHECK_EQ(0, (uptr)child_stack % 16); 1496 child_stack = (char *)child_stack - 7 * sizeof(unsigned int); 1497 ((unsigned int *)child_stack)[0] = (uptr)flags; 1498 ((unsigned int *)child_stack)[1] = (uptr)0; 1499 ((unsigned int *)child_stack)[2] = (uptr)fn; 1500 ((unsigned int *)child_stack)[3] = (uptr)arg; 1501 __asm__ __volatile__( 1502 /* %eax = syscall(%eax = SYSCALL(clone), 1503 * %ebx = flags, 1504 * %ecx = child_stack, 1505 * %edx = parent_tidptr, 1506 * %esi = new_tls, 1507 * %edi = child_tidptr) 1508 */ 1509 1510 /* Obtain flags */ 1511 "movl (%%ecx), %%ebx\n" 1512 /* Do the system call */ 1513 "pushl %%ebx\n" 1514 "pushl %%esi\n" 1515 "pushl %%edi\n" 1516 /* Remember the flag value. */ 1517 "movl %%ebx, (%%ecx)\n" 1518 "int $0x80\n" 1519 "popl %%edi\n" 1520 "popl %%esi\n" 1521 "popl %%ebx\n" 1522 1523 /* if (%eax != 0) 1524 * return; 1525 */ 1526 1527 "test %%eax,%%eax\n" 1528 "jnz 1f\n" 1529 1530 /* terminate the stack frame */ 1531 "xorl %%ebp,%%ebp\n" 1532 /* Call FN. */ 1533 "call *%%ebx\n" 1534#ifdef PIC 1535 "call here\n" 1536 "here:\n" 1537 "popl %%ebx\n" 1538 "addl $_GLOBAL_OFFSET_TABLE_+[.-here], %%ebx\n" 1539#endif 1540 /* Call exit */ 1541 "movl %%eax, %%ebx\n" 1542 "movl %2, %%eax\n" 1543 "int $0x80\n" 1544 "1:\n" 1545 : "=a" (res) 1546 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1547 "c"(child_stack), 1548 "d"(parent_tidptr), 1549 "S"(newtls), 1550 "D"(child_tidptr) 1551 : "memory"); 1552 return res; 1553} 1554#elif defined(__arm__) && SANITIZER_LINUX 1555uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1556 int *parent_tidptr, void *newtls, int *child_tidptr) { 1557 unsigned int res; 1558 if (!fn || !child_stack) 1559 return -EINVAL; 1560 child_stack = (char *)child_stack - 2 * sizeof(unsigned int); 1561 ((unsigned int *)child_stack)[0] = (uptr)fn; 1562 ((unsigned int *)child_stack)[1] = (uptr)arg; 1563 register int r0 __asm__("r0") = flags; 1564 register void *r1 __asm__("r1") = child_stack; 1565 register int *r2 __asm__("r2") = parent_tidptr; 1566 register void *r3 __asm__("r3") = newtls; 1567 register int *r4 __asm__("r4") = child_tidptr; 1568 register int r7 __asm__("r7") = __NR_clone; 1569 1570#if __ARM_ARCH > 4 || defined (__ARM_ARCH_4T__) 1571# define ARCH_HAS_BX 1572#endif 1573#if __ARM_ARCH > 4 1574# define ARCH_HAS_BLX 1575#endif 1576 1577#ifdef ARCH_HAS_BX 1578# ifdef ARCH_HAS_BLX 1579# define BLX(R) "blx " #R "\n" 1580# else 1581# define BLX(R) "mov lr, pc; bx " #R "\n" 1582# endif 1583#else 1584# define BLX(R) "mov lr, pc; mov pc," #R "\n" 1585#endif 1586 1587 __asm__ __volatile__( 1588 /* %r0 = syscall(%r7 = SYSCALL(clone), 1589 * %r0 = flags, 1590 * %r1 = child_stack, 1591 * %r2 = parent_tidptr, 1592 * %r3 = new_tls, 1593 * %r4 = child_tidptr) 1594 */ 1595 1596 /* Do the system call */ 1597 "swi 0x0\n" 1598 1599 /* if (%r0 != 0) 1600 * return %r0; 1601 */ 1602 "cmp r0, #0\n" 1603 "bne 1f\n" 1604 1605 /* In the child, now. Call "fn(arg)". */ 1606 "ldr r0, [sp, #4]\n" 1607 "ldr ip, [sp], #8\n" 1608 BLX(ip) 1609 /* Call _exit(%r0). */ 1610 "mov r7, %7\n" 1611 "swi 0x0\n" 1612 "1:\n" 1613 "mov %0, r0\n" 1614 : "=r"(res) 1615 : "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r7), 1616 "i"(__NR_exit) 1617 : "memory"); 1618 return res; 1619} 1620#endif // defined(__x86_64__) && SANITIZER_LINUX 1621 1622#if SANITIZER_ANDROID 1623#if __ANDROID_API__ < 21 1624extern "C" __attribute__((weak)) int dl_iterate_phdr( 1625 int (*)(struct dl_phdr_info *, size_t, void *), void *); 1626#endif 1627 1628static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size, 1629 void *data) { 1630 // Any name starting with "lib" indicates a bug in L where library base names 1631 // are returned instead of paths. 1632 if (info->dlpi_name && info->dlpi_name[0] == 'l' && 1633 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') { 1634 *(bool *)data = true; 1635 return 1; 1636 } 1637 return 0; 1638} 1639 1640static atomic_uint32_t android_api_level; 1641 1642static AndroidApiLevel AndroidDetectApiLevelStatic() { 1643#if __ANDROID_API__ <= 19 1644 return ANDROID_KITKAT; 1645#elif __ANDROID_API__ <= 22 1646 return ANDROID_LOLLIPOP_MR1; 1647#else 1648 return ANDROID_POST_LOLLIPOP; 1649#endif 1650} 1651 1652static AndroidApiLevel AndroidDetectApiLevel() { 1653 if (!&dl_iterate_phdr) 1654 return ANDROID_KITKAT; // K or lower 1655 bool base_name_seen = false; 1656 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen); 1657 if (base_name_seen) 1658 return ANDROID_LOLLIPOP_MR1; // L MR1 1659 return ANDROID_POST_LOLLIPOP; // post-L 1660 // Plain L (API level 21) is completely broken wrt ASan and not very 1661 // interesting to detect. 1662} 1663 1664extern "C" __attribute__((weak)) void* _DYNAMIC; 1665 1666AndroidApiLevel AndroidGetApiLevel() { 1667 AndroidApiLevel level = 1668 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed); 1669 if (level) return level; 1670 level = &_DYNAMIC == nullptr ? AndroidDetectApiLevelStatic() 1671 : AndroidDetectApiLevel(); 1672 atomic_store(&android_api_level, level, memory_order_relaxed); 1673 return level; 1674} 1675 1676#endif 1677 1678static HandleSignalMode GetHandleSignalModeImpl(int signum) { 1679 switch (signum) { 1680 case SIGABRT: 1681 return common_flags()->handle_abort; 1682 case SIGILL: 1683 return common_flags()->handle_sigill; 1684 case SIGTRAP: 1685 return common_flags()->handle_sigtrap; 1686 case SIGFPE: 1687 return common_flags()->handle_sigfpe; 1688 case SIGSEGV: 1689 return common_flags()->handle_segv; 1690 case SIGBUS: 1691 return common_flags()->handle_sigbus; 1692 } 1693 return kHandleSignalNo; 1694} 1695 1696HandleSignalMode GetHandleSignalMode(int signum) { 1697 HandleSignalMode result = GetHandleSignalModeImpl(signum); 1698 if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler) 1699 return kHandleSignalExclusive; 1700 return result; 1701} 1702 1703#if !SANITIZER_GO 1704void *internal_start_thread(void(*func)(void *arg), void *arg) { 1705 // Start the thread with signals blocked, otherwise it can steal user signals. 1706 __sanitizer_sigset_t set, old; 1707 internal_sigfillset(&set); 1708#if SANITIZER_LINUX && !SANITIZER_ANDROID 1709 // Glibc uses SIGSETXID signal during setuid call. If this signal is blocked 1710 // on any thread, setuid call hangs (see test/tsan/setuid.c). 1711 internal_sigdelset(&set, 33); 1712#endif 1713 internal_sigprocmask(SIG_SETMASK, &set, &old); 1714 void *th; 1715 real_pthread_create(&th, nullptr, (void*(*)(void *arg))func, arg); 1716 internal_sigprocmask(SIG_SETMASK, &old, nullptr); 1717 return th; 1718} 1719 1720void internal_join_thread(void *th) { 1721 real_pthread_join(th, nullptr); 1722} 1723#else 1724void *internal_start_thread(void (*func)(void *), void *arg) { return 0; } 1725 1726void internal_join_thread(void *th) {} 1727#endif 1728 1729#if defined(__aarch64__) 1730// Android headers in the older NDK releases miss this definition. 1731struct __sanitizer_esr_context { 1732 struct _aarch64_ctx head; 1733 uint64_t esr; 1734}; 1735 1736static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) { 1737 static const u32 kEsrMagic = 0x45535201; 1738 u8 *aux = ucontext->uc_mcontext.__reserved; 1739 while (true) { 1740 _aarch64_ctx *ctx = (_aarch64_ctx *)aux; 1741 if (ctx->size == 0) break; 1742 if (ctx->magic == kEsrMagic) { 1743 *esr = ((__sanitizer_esr_context *)ctx)->esr; 1744 return true; 1745 } 1746 aux += ctx->size; 1747 } 1748 return false; 1749} 1750#endif 1751 1752#if SANITIZER_OPENBSD 1753using Context = sigcontext; 1754#else 1755using Context = ucontext_t; 1756#endif 1757 1758SignalContext::WriteFlag SignalContext::GetWriteFlag() const { 1759 Context *ucontext = (Context *)context; 1760#if defined(__x86_64__) || defined(__i386__) 1761 static const uptr PF_WRITE = 1U << 1; 1762#if SANITIZER_FREEBSD 1763 uptr err = ucontext->uc_mcontext.mc_err; 1764#elif SANITIZER_NETBSD 1765 uptr err = ucontext->uc_mcontext.__gregs[_REG_ERR]; 1766#elif SANITIZER_OPENBSD 1767 uptr err = ucontext->sc_err; 1768#elif SANITIZER_SOLARIS && defined(__i386__) 1769 const int Err = 13; 1770 uptr err = ucontext->uc_mcontext.gregs[Err]; 1771#else 1772 uptr err = ucontext->uc_mcontext.gregs[REG_ERR]; 1773#endif // SANITIZER_FREEBSD 1774 return err & PF_WRITE ? WRITE : READ; 1775#elif defined(__mips__) 1776 uint32_t *exception_source; 1777 uint32_t faulty_instruction; 1778 uint32_t op_code; 1779 1780 exception_source = (uint32_t *)ucontext->uc_mcontext.pc; 1781 faulty_instruction = (uint32_t)(*exception_source); 1782 1783 op_code = (faulty_instruction >> 26) & 0x3f; 1784 1785 // FIXME: Add support for FPU, microMIPS, DSP, MSA memory instructions. 1786 switch (op_code) { 1787 case 0x28: // sb 1788 case 0x29: // sh 1789 case 0x2b: // sw 1790 case 0x3f: // sd 1791#if __mips_isa_rev < 6 1792 case 0x2c: // sdl 1793 case 0x2d: // sdr 1794 case 0x2a: // swl 1795 case 0x2e: // swr 1796#endif 1797 return SignalContext::WRITE; 1798 1799 case 0x20: // lb 1800 case 0x24: // lbu 1801 case 0x21: // lh 1802 case 0x25: // lhu 1803 case 0x23: // lw 1804 case 0x27: // lwu 1805 case 0x37: // ld 1806#if __mips_isa_rev < 6 1807 case 0x1a: // ldl 1808 case 0x1b: // ldr 1809 case 0x22: // lwl 1810 case 0x26: // lwr 1811#endif 1812 return SignalContext::READ; 1813#if __mips_isa_rev == 6 1814 case 0x3b: // pcrel 1815 op_code = (faulty_instruction >> 19) & 0x3; 1816 switch (op_code) { 1817 case 0x1: // lwpc 1818 case 0x2: // lwupc 1819 return SignalContext::READ; 1820 } 1821#endif 1822 } 1823 return SignalContext::UNKNOWN; 1824#elif defined(__arm__) 1825 static const uptr FSR_WRITE = 1U << 11; 1826 uptr fsr = ucontext->uc_mcontext.error_code; 1827 return fsr & FSR_WRITE ? WRITE : READ; 1828#elif defined(__aarch64__) 1829 static const u64 ESR_ELx_WNR = 1U << 6; 1830 u64 esr; 1831 if (!Aarch64GetESR(ucontext, &esr)) return UNKNOWN; 1832 return esr & ESR_ELx_WNR ? WRITE : READ; 1833#elif defined(__sparc__) 1834 // Decode the instruction to determine the access type. 1835 // From OpenSolaris $SRC/uts/sun4/os/trap.c (get_accesstype). 1836#if SANITIZER_SOLARIS 1837 uptr pc = ucontext->uc_mcontext.gregs[REG_PC]; 1838#else 1839 // Historical BSDism here. 1840 struct sigcontext *scontext = (struct sigcontext *)context; 1841#if defined(__arch64__) 1842 uptr pc = scontext->sigc_regs.tpc; 1843#else 1844 uptr pc = scontext->si_regs.pc; 1845#endif 1846#endif 1847 u32 instr = *(u32 *)pc; 1848 return (instr >> 21) & 1 ? WRITE: READ; 1849#else 1850 (void)ucontext; 1851 return UNKNOWN; // FIXME: Implement. 1852#endif 1853} 1854 1855bool SignalContext::IsTrueFaultingAddress() const { 1856 auto si = static_cast<const siginfo_t *>(siginfo); 1857 // SIGSEGV signals without a true fault address have si_code set to 128. 1858 return si->si_signo == SIGSEGV && si->si_code != 128; 1859} 1860 1861void SignalContext::DumpAllRegisters(void *context) { 1862 // FIXME: Implement this. 1863} 1864 1865static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) { 1866#if SANITIZER_NETBSD 1867 // This covers all NetBSD architectures 1868 ucontext_t *ucontext = (ucontext_t *)context; 1869 *pc = _UC_MACHINE_PC(ucontext); 1870 *bp = _UC_MACHINE_FP(ucontext); 1871 *sp = _UC_MACHINE_SP(ucontext); 1872#elif defined(__arm__) 1873 ucontext_t *ucontext = (ucontext_t*)context; 1874 *pc = ucontext->uc_mcontext.arm_pc; 1875 *bp = ucontext->uc_mcontext.arm_fp; 1876 *sp = ucontext->uc_mcontext.arm_sp; 1877#elif defined(__aarch64__) 1878 ucontext_t *ucontext = (ucontext_t*)context; 1879 *pc = ucontext->uc_mcontext.pc; 1880 *bp = ucontext->uc_mcontext.regs[29]; 1881 *sp = ucontext->uc_mcontext.sp; 1882#elif defined(__hppa__) 1883 ucontext_t *ucontext = (ucontext_t*)context; 1884 *pc = ucontext->uc_mcontext.sc_iaoq[0]; 1885 /* GCC uses %r3 whenever a frame pointer is needed. */ 1886 *bp = ucontext->uc_mcontext.sc_gr[3]; 1887 *sp = ucontext->uc_mcontext.sc_gr[30]; 1888#elif defined(__x86_64__) 1889# if SANITIZER_FREEBSD 1890 ucontext_t *ucontext = (ucontext_t*)context; 1891 *pc = ucontext->uc_mcontext.mc_rip; 1892 *bp = ucontext->uc_mcontext.mc_rbp; 1893 *sp = ucontext->uc_mcontext.mc_rsp; 1894#elif SANITIZER_OPENBSD 1895 sigcontext *ucontext = (sigcontext *)context; 1896 *pc = ucontext->sc_rip; 1897 *bp = ucontext->sc_rbp; 1898 *sp = ucontext->sc_rsp; 1899# else 1900 ucontext_t *ucontext = (ucontext_t*)context; 1901 *pc = ucontext->uc_mcontext.gregs[REG_RIP]; 1902 *bp = ucontext->uc_mcontext.gregs[REG_RBP]; 1903 *sp = ucontext->uc_mcontext.gregs[REG_RSP]; 1904# endif 1905#elif defined(__i386__) 1906# if SANITIZER_FREEBSD 1907 ucontext_t *ucontext = (ucontext_t*)context; 1908 *pc = ucontext->uc_mcontext.mc_eip; 1909 *bp = ucontext->uc_mcontext.mc_ebp; 1910 *sp = ucontext->uc_mcontext.mc_esp; 1911#elif SANITIZER_OPENBSD 1912 sigcontext *ucontext = (sigcontext *)context; 1913 *pc = ucontext->sc_eip; 1914 *bp = ucontext->sc_ebp; 1915 *sp = ucontext->sc_esp; 1916# else 1917 ucontext_t *ucontext = (ucontext_t*)context; 1918# if SANITIZER_SOLARIS 1919 /* Use the numeric values: the symbolic ones are undefined by llvm 1920 include/llvm/Support/Solaris.h. */ 1921# ifndef REG_EIP 1922# define REG_EIP 14 // REG_PC 1923# endif 1924# ifndef REG_EBP 1925# define REG_EBP 6 // REG_FP 1926# endif 1927# ifndef REG_ESP 1928# define REG_ESP 17 // REG_SP 1929# endif 1930# endif 1931 *pc = ucontext->uc_mcontext.gregs[REG_EIP]; 1932 *bp = ucontext->uc_mcontext.gregs[REG_EBP]; 1933 *sp = ucontext->uc_mcontext.gregs[REG_ESP]; 1934# endif 1935#elif defined(__powerpc__) || defined(__powerpc64__) 1936 ucontext_t *ucontext = (ucontext_t*)context; 1937 *pc = ucontext->uc_mcontext.regs->nip; 1938 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1]; 1939 // The powerpc{,64}-linux ABIs do not specify r31 as the frame 1940 // pointer, but GCC always uses r31 when we need a frame pointer. 1941 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31]; 1942#elif defined(__sparc__) 1943#if defined(__arch64__) || defined(__sparcv9) 1944#define STACK_BIAS 2047 1945#else 1946#define STACK_BIAS 0 1947# endif 1948# if SANITIZER_SOLARIS 1949 ucontext_t *ucontext = (ucontext_t *)context; 1950 *pc = ucontext->uc_mcontext.gregs[REG_PC]; 1951 *sp = ucontext->uc_mcontext.gregs[REG_O6] + STACK_BIAS; 1952#else 1953 // Historical BSDism here. 1954 struct sigcontext *scontext = (struct sigcontext *)context; 1955#if defined(__arch64__) 1956 *pc = scontext->sigc_regs.tpc; 1957 *sp = scontext->sigc_regs.u_regs[14] + STACK_BIAS; 1958#else 1959 *pc = scontext->si_regs.pc; 1960 *sp = scontext->si_regs.u_regs[14]; 1961#endif 1962# endif 1963 *bp = (uptr)((uhwptr *)*sp)[14] + STACK_BIAS; 1964#elif defined(__mips__) 1965 ucontext_t *ucontext = (ucontext_t*)context; 1966 *pc = ucontext->uc_mcontext.pc; 1967 *bp = ucontext->uc_mcontext.gregs[30]; 1968 *sp = ucontext->uc_mcontext.gregs[29]; 1969#elif defined(__s390__) 1970 ucontext_t *ucontext = (ucontext_t*)context; 1971# if defined(__s390x__) 1972 *pc = ucontext->uc_mcontext.psw.addr; 1973# else 1974 *pc = ucontext->uc_mcontext.psw.addr & 0x7fffffff; 1975# endif 1976 *bp = ucontext->uc_mcontext.gregs[11]; 1977 *sp = ucontext->uc_mcontext.gregs[15]; 1978#elif defined(__riscv) 1979 ucontext_t *ucontext = (ucontext_t*)context; 1980 *pc = ucontext->uc_mcontext.__gregs[REG_PC]; 1981 *bp = ucontext->uc_mcontext.__gregs[REG_S0]; 1982 *sp = ucontext->uc_mcontext.__gregs[REG_SP]; 1983#else 1984# error "Unsupported arch" 1985#endif 1986} 1987 1988void SignalContext::InitPcSpBp() { GetPcSpBp(context, &pc, &sp, &bp); } 1989 1990void InitializePlatformEarly() { 1991 // Do nothing. 1992} 1993 1994void MaybeReexec() { 1995 // No need to re-exec on Linux. 1996} 1997 1998void CheckASLR() { 1999#if SANITIZER_NETBSD 2000 int mib[3]; 2001 int paxflags; 2002 uptr len = sizeof(paxflags); 2003 2004 mib[0] = CTL_PROC; 2005 mib[1] = internal_getpid(); 2006 mib[2] = PROC_PID_PAXFLAGS; 2007 2008 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2009 Printf("sysctl failed\n"); 2010 Die(); 2011 } 2012 2013 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_ASLR)) { 2014 Printf("This sanitizer is not compatible with enabled ASLR\n"); 2015 Die(); 2016 } 2017#elif SANITIZER_PPC64V2 2018 // Disable ASLR for Linux PPC64LE. 2019 int old_personality = personality(0xffffffff); 2020 if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) { 2021 VReport(1, "WARNING: Program is being run with address space layout " 2022 "randomization (ASLR) enabled which prevents the thread and " 2023 "memory sanitizers from working on powerpc64le.\n" 2024 "ASLR will be disabled and the program re-executed.\n"); 2025 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1); 2026 ReExec(); 2027 } 2028#elif SANITIZER_FREEBSD 2029 int aslr_pie; 2030 uptr len = sizeof(aslr_pie); 2031#if SANITIZER_WORDSIZE == 64 2032 if (UNLIKELY(internal_sysctlbyname("kern.elf64.aslr.pie_enable", 2033 &aslr_pie, &len, NULL, 0) == -1)) { 2034 // We're making things less 'dramatic' here since 2035 // the OID is not necessarily guaranteed to be here 2036 // just yet regarding FreeBSD release 2037 return; 2038 } 2039 2040 if (aslr_pie > 0) { 2041 Printf("This sanitizer is not compatible with enabled ASLR " 2042 "and binaries compiled with PIE\n"); 2043 Die(); 2044 } 2045#endif 2046 // there might be 32 bits compat for 64 bits 2047 if (UNLIKELY(internal_sysctlbyname("kern.elf32.aslr.pie_enable", 2048 &aslr_pie, &len, NULL, 0) == -1)) { 2049 return; 2050 } 2051 2052 if (aslr_pie > 0) { 2053 Printf("This sanitizer is not compatible with enabled ASLR " 2054 "and binaries compiled with PIE\n"); 2055 Die(); 2056 } 2057#else 2058 // Do nothing 2059#endif 2060} 2061 2062void CheckMPROTECT() { 2063#if SANITIZER_NETBSD 2064 int mib[3]; 2065 int paxflags; 2066 uptr len = sizeof(paxflags); 2067 2068 mib[0] = CTL_PROC; 2069 mib[1] = internal_getpid(); 2070 mib[2] = PROC_PID_PAXFLAGS; 2071 2072 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2073 Printf("sysctl failed\n"); 2074 Die(); 2075 } 2076 2077 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_MPROTECT)) { 2078 Printf("This sanitizer is not compatible with enabled MPROTECT\n"); 2079 Die(); 2080 } 2081#else 2082 // Do nothing 2083#endif 2084} 2085 2086void PrintModuleMap() { } 2087 2088void CheckNoDeepBind(const char *filename, int flag) { 2089#ifdef RTLD_DEEPBIND 2090 if (flag & RTLD_DEEPBIND) { 2091 Report( 2092 "You are trying to dlopen a %s shared library with RTLD_DEEPBIND flag" 2093 " which is incompatibe with sanitizer runtime " 2094 "(see https://github.com/google/sanitizers/issues/611 for details" 2095 "). If you want to run %s library under sanitizers please remove " 2096 "RTLD_DEEPBIND from dlopen flags.\n", 2097 filename, filename); 2098 Die(); 2099 } 2100#endif 2101} 2102 2103uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding, 2104 uptr *largest_gap_found, 2105 uptr *max_occupied_addr) { 2106 UNREACHABLE("FindAvailableMemoryRange is not available"); 2107 return 0; 2108} 2109 2110bool GetRandom(void *buffer, uptr length, bool blocking) { 2111 if (!buffer || !length || length > 256) 2112 return false; 2113#if SANITIZER_USE_GETENTROPY 2114 uptr rnd = getentropy(buffer, length); 2115 int rverrno = 0; 2116 if (internal_iserror(rnd, &rverrno) && rverrno == EFAULT) 2117 return false; 2118 else if (rnd == 0) 2119 return true; 2120#endif // SANITIZER_USE_GETENTROPY 2121 2122#if SANITIZER_USE_GETRANDOM 2123 static atomic_uint8_t skip_getrandom_syscall; 2124 if (!atomic_load_relaxed(&skip_getrandom_syscall)) { 2125 // Up to 256 bytes, getrandom will not be interrupted. 2126 uptr res = internal_syscall(SYSCALL(getrandom), buffer, length, 2127 blocking ? 0 : GRND_NONBLOCK); 2128 int rverrno = 0; 2129 if (internal_iserror(res, &rverrno) && rverrno == ENOSYS) 2130 atomic_store_relaxed(&skip_getrandom_syscall, 1); 2131 else if (res == length) 2132 return true; 2133 } 2134#endif // SANITIZER_USE_GETRANDOM 2135 // Up to 256 bytes, a read off /dev/urandom will not be interrupted. 2136 // blocking is moot here, O_NONBLOCK has no effect when opening /dev/urandom. 2137 uptr fd = internal_open("/dev/urandom", O_RDONLY); 2138 if (internal_iserror(fd)) 2139 return false; 2140 uptr res = internal_read(fd, buffer, length); 2141 if (internal_iserror(res)) 2142 return false; 2143 internal_close(fd); 2144 return true; 2145} 2146 2147} // namespace __sanitizer 2148 2149#endif 2150