1 //===-- sanitizer_linux.cc ------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file is shared between AddressSanitizer and ThreadSanitizer 11 // run-time libraries and implements linux-specific functions from 12 // sanitizer_libc.h. 13 //===----------------------------------------------------------------------===// 14 15 #include "sanitizer_platform.h" 16 17 #if SANITIZER_FREEBSD || SANITIZER_LINUX 18 19 #include "sanitizer_common.h" 20 #include "sanitizer_flags.h" 21 #include "sanitizer_internal_defs.h" 22 #include "sanitizer_libc.h" 23 #include "sanitizer_linux.h" 24 #include "sanitizer_mutex.h" 25 #include "sanitizer_placement_new.h" 26 #include "sanitizer_procmaps.h" 27 #include "sanitizer_stacktrace.h" 28 #include "sanitizer_symbolizer.h" 29 30 #if !SANITIZER_FREEBSD 31 #include <asm/param.h> 32 #endif 33 34 // For mips64, syscall(__NR_stat) fills the buffer in the 'struct kernel_stat' 35 // format. Struct kernel_stat is defined as 'struct stat' in asm/stat.h. To 36 // access stat from asm/stat.h, without conflicting with definition in 37 // sys/stat.h, we use this trick. 38 #if defined(__mips64) 39 #include <asm/unistd.h> 40 #include <sys/types.h> 41 #define stat kernel_stat 42 #include <asm/stat.h> 43 #undef stat 44 #endif 45 46 #include <dlfcn.h> 47 #include <errno.h> 48 #include <fcntl.h> 49 #include <link.h> 50 #include <pthread.h> 51 #include <sched.h> 52 #include <sys/mman.h> 53 #include <sys/ptrace.h> 54 #include <sys/resource.h> 55 #include <sys/stat.h> 56 #include <sys/syscall.h> 57 #include <sys/time.h> 58 #include <sys/types.h> 59 #include <ucontext.h> 60 #include <unistd.h> 61 62 #if SANITIZER_FREEBSD 63 #include <sys/exec.h> 64 #include <sys/sysctl.h> 65 #include <vm/vm_param.h> 66 #include <vm/pmap.h> 67 #include <machine/atomic.h> 68 extern "C" { 69 // <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on 70 // FreeBSD 9.2 and 10.0. 71 #include <sys/umtx.h> 72 } 73 extern char **environ; // provided by crt1 74 #endif // SANITIZER_FREEBSD 75 76 #if !SANITIZER_ANDROID 77 #include <sys/signal.h> 78 #endif 79 80 #if SANITIZER_LINUX 81 // <linux/time.h> 82 struct kernel_timeval { 83 long tv_sec; 84 long tv_usec; 85 }; 86 87 // <linux/futex.h> is broken on some linux distributions. 88 const int FUTEX_WAIT = 0; 89 const int FUTEX_WAKE = 1; 90 #endif // SANITIZER_LINUX 91 92 // Are we using 32-bit or 64-bit Linux syscalls? 93 // x32 (which defines __x86_64__) has SANITIZER_WORDSIZE == 32 94 // but it still needs to use 64-bit syscalls. 95 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__powerpc64__) || \ 96 SANITIZER_WORDSIZE == 64) 97 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 1 98 #else 99 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 0 100 #endif 101 102 #if defined(__x86_64__) 103 extern "C" { 104 extern void internal_sigreturn(); 105 } 106 #endif 107 108 namespace __sanitizer { 109 110 #if SANITIZER_LINUX && defined(__x86_64__) 111 #include "sanitizer_syscall_linux_x86_64.inc" 112 #elif SANITIZER_LINUX && defined(__aarch64__) 113 #include "sanitizer_syscall_linux_aarch64.inc" 114 #else 115 #include "sanitizer_syscall_generic.inc" 116 #endif 117 118 // --------------- sanitizer_libc.h 119 #if !SANITIZER_S390 120 uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd, 121 OFF_T offset) { 122 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 123 return internal_syscall(SYSCALL(mmap), (uptr)addr, length, prot, flags, fd, 124 offset); 125 #else 126 // mmap2 specifies file offset in 4096-byte units. 127 CHECK(IsAligned(offset, 4096)); 128 return internal_syscall(SYSCALL(mmap2), addr, length, prot, flags, fd, 129 offset / 4096); 130 #endif 131 } 132 #endif // !SANITIZER_S390 133 134 uptr internal_munmap(void *addr, uptr length) { 135 return internal_syscall(SYSCALL(munmap), (uptr)addr, length); 136 } 137 138 int internal_mprotect(void *addr, uptr length, int prot) { 139 return internal_syscall(SYSCALL(mprotect), (uptr)addr, length, prot); 140 } 141 142 uptr internal_close(fd_t fd) { 143 return internal_syscall(SYSCALL(close), fd); 144 } 145 146 uptr internal_open(const char *filename, int flags) { 147 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 148 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags); 149 #else 150 return internal_syscall(SYSCALL(open), (uptr)filename, flags); 151 #endif 152 } 153 154 uptr internal_open(const char *filename, int flags, u32 mode) { 155 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 156 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags, 157 mode); 158 #else 159 return internal_syscall(SYSCALL(open), (uptr)filename, flags, mode); 160 #endif 161 } 162 163 uptr internal_read(fd_t fd, void *buf, uptr count) { 164 sptr res; 165 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(read), fd, (uptr)buf, 166 count)); 167 return res; 168 } 169 170 uptr internal_write(fd_t fd, const void *buf, uptr count) { 171 sptr res; 172 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(write), fd, (uptr)buf, 173 count)); 174 return res; 175 } 176 177 uptr internal_ftruncate(fd_t fd, uptr size) { 178 sptr res; 179 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(ftruncate), fd, 180 (OFF_T)size)); 181 return res; 182 } 183 184 #if !SANITIZER_LINUX_USES_64BIT_SYSCALLS && !SANITIZER_FREEBSD 185 static void stat64_to_stat(struct stat64 *in, struct stat *out) { 186 internal_memset(out, 0, sizeof(*out)); 187 out->st_dev = in->st_dev; 188 out->st_ino = in->st_ino; 189 out->st_mode = in->st_mode; 190 out->st_nlink = in->st_nlink; 191 out->st_uid = in->st_uid; 192 out->st_gid = in->st_gid; 193 out->st_rdev = in->st_rdev; 194 out->st_size = in->st_size; 195 out->st_blksize = in->st_blksize; 196 out->st_blocks = in->st_blocks; 197 out->st_atime = in->st_atime; 198 out->st_mtime = in->st_mtime; 199 out->st_ctime = in->st_ctime; 200 out->st_ino = in->st_ino; 201 } 202 #endif 203 204 #if defined(__mips64) 205 static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) { 206 internal_memset(out, 0, sizeof(*out)); 207 out->st_dev = in->st_dev; 208 out->st_ino = in->st_ino; 209 out->st_mode = in->st_mode; 210 out->st_nlink = in->st_nlink; 211 out->st_uid = in->st_uid; 212 out->st_gid = in->st_gid; 213 out->st_rdev = in->st_rdev; 214 out->st_size = in->st_size; 215 out->st_blksize = in->st_blksize; 216 out->st_blocks = in->st_blocks; 217 out->st_atime = in->st_atime_nsec; 218 out->st_mtime = in->st_mtime_nsec; 219 out->st_ctime = in->st_ctime_nsec; 220 out->st_ino = in->st_ino; 221 } 222 #endif 223 224 uptr internal_stat(const char *path, void *buf) { 225 #if SANITIZER_FREEBSD 226 return internal_syscall(SYSCALL(stat), path, buf); 227 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 228 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, 229 (uptr)buf, 0); 230 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 231 # if defined(__mips64) 232 // For mips64, stat syscall fills buffer in the format of kernel_stat 233 struct kernel_stat kbuf; 234 int res = internal_syscall(SYSCALL(stat), path, &kbuf); 235 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 236 return res; 237 # else 238 return internal_syscall(SYSCALL(stat), (uptr)path, (uptr)buf); 239 # endif 240 #else 241 struct stat64 buf64; 242 int res = internal_syscall(SYSCALL(stat64), path, &buf64); 243 stat64_to_stat(&buf64, (struct stat *)buf); 244 return res; 245 #endif 246 } 247 248 uptr internal_lstat(const char *path, void *buf) { 249 #if SANITIZER_FREEBSD 250 return internal_syscall(SYSCALL(lstat), path, buf); 251 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 252 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, 253 (uptr)buf, AT_SYMLINK_NOFOLLOW); 254 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 255 # if SANITIZER_MIPS64 256 // For mips64, lstat syscall fills buffer in the format of kernel_stat 257 struct kernel_stat kbuf; 258 int res = internal_syscall(SYSCALL(lstat), path, &kbuf); 259 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 260 return res; 261 # else 262 return internal_syscall(SYSCALL(lstat), (uptr)path, (uptr)buf); 263 # endif 264 #else 265 struct stat64 buf64; 266 int res = internal_syscall(SYSCALL(lstat64), path, &buf64); 267 stat64_to_stat(&buf64, (struct stat *)buf); 268 return res; 269 #endif 270 } 271 272 uptr internal_fstat(fd_t fd, void *buf) { 273 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 274 # if SANITIZER_MIPS64 275 // For mips64, fstat syscall fills buffer in the format of kernel_stat 276 struct kernel_stat kbuf; 277 int res = internal_syscall(SYSCALL(fstat), fd, &kbuf); 278 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 279 return res; 280 # else 281 return internal_syscall(SYSCALL(fstat), fd, (uptr)buf); 282 # endif 283 #else 284 struct stat64 buf64; 285 int res = internal_syscall(SYSCALL(fstat64), fd, &buf64); 286 stat64_to_stat(&buf64, (struct stat *)buf); 287 return res; 288 #endif 289 } 290 291 uptr internal_filesize(fd_t fd) { 292 struct stat st; 293 if (internal_fstat(fd, &st)) 294 return -1; 295 return (uptr)st.st_size; 296 } 297 298 uptr internal_dup2(int oldfd, int newfd) { 299 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 300 return internal_syscall(SYSCALL(dup3), oldfd, newfd, 0); 301 #else 302 return internal_syscall(SYSCALL(dup2), oldfd, newfd); 303 #endif 304 } 305 306 uptr internal_readlink(const char *path, char *buf, uptr bufsize) { 307 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 308 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD, 309 (uptr)path, (uptr)buf, bufsize); 310 #else 311 return internal_syscall(SYSCALL(readlink), (uptr)path, (uptr)buf, bufsize); 312 #endif 313 } 314 315 uptr internal_unlink(const char *path) { 316 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 317 return internal_syscall(SYSCALL(unlinkat), AT_FDCWD, (uptr)path, 0); 318 #else 319 return internal_syscall(SYSCALL(unlink), (uptr)path); 320 #endif 321 } 322 323 uptr internal_rename(const char *oldpath, const char *newpath) { 324 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 325 return internal_syscall(SYSCALL(renameat), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 326 (uptr)newpath); 327 #else 328 return internal_syscall(SYSCALL(rename), (uptr)oldpath, (uptr)newpath); 329 #endif 330 } 331 332 uptr internal_sched_yield() { 333 return internal_syscall(SYSCALL(sched_yield)); 334 } 335 336 void internal__exit(int exitcode) { 337 #if SANITIZER_FREEBSD 338 internal_syscall(SYSCALL(exit), exitcode); 339 #else 340 internal_syscall(SYSCALL(exit_group), exitcode); 341 #endif 342 Die(); // Unreachable. 343 } 344 345 unsigned int internal_sleep(unsigned int seconds) { 346 struct timespec ts; 347 ts.tv_sec = 1; 348 ts.tv_nsec = 0; 349 int res = internal_syscall(SYSCALL(nanosleep), &ts, &ts); 350 if (res) return ts.tv_sec; 351 return 0; 352 } 353 354 uptr internal_execve(const char *filename, char *const argv[], 355 char *const envp[]) { 356 return internal_syscall(SYSCALL(execve), (uptr)filename, (uptr)argv, 357 (uptr)envp); 358 } 359 360 // ----------------- sanitizer_common.h 361 bool FileExists(const char *filename) { 362 struct stat st; 363 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 364 if (internal_syscall(SYSCALL(newfstatat), AT_FDCWD, filename, &st, 0)) 365 #else 366 if (internal_stat(filename, &st)) 367 #endif 368 return false; 369 // Sanity check: filename is a regular file. 370 return S_ISREG(st.st_mode); 371 } 372 373 uptr GetTid() { 374 #if SANITIZER_FREEBSD 375 return (uptr)pthread_self(); 376 #else 377 return internal_syscall(SYSCALL(gettid)); 378 #endif 379 } 380 381 u64 NanoTime() { 382 #if SANITIZER_FREEBSD 383 timeval tv; 384 #else 385 kernel_timeval tv; 386 #endif 387 internal_memset(&tv, 0, sizeof(tv)); 388 internal_syscall(SYSCALL(gettimeofday), (uptr)&tv, 0); 389 return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000; 390 } 391 392 // Like getenv, but reads env directly from /proc (on Linux) or parses the 393 // 'environ' array (on FreeBSD) and does not use libc. This function should be 394 // called first inside __asan_init. 395 const char *GetEnv(const char *name) { 396 #if SANITIZER_FREEBSD 397 if (::environ != 0) { 398 uptr NameLen = internal_strlen(name); 399 for (char **Env = ::environ; *Env != 0; Env++) { 400 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=') 401 return (*Env) + NameLen + 1; 402 } 403 } 404 return 0; // Not found. 405 #elif SANITIZER_LINUX 406 static char *environ; 407 static uptr len; 408 static bool inited; 409 if (!inited) { 410 inited = true; 411 uptr environ_size; 412 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len)) 413 environ = nullptr; 414 } 415 if (!environ || len == 0) return nullptr; 416 uptr namelen = internal_strlen(name); 417 const char *p = environ; 418 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer 419 // proc file has the format NAME=value\0NAME=value\0NAME=value\0... 420 const char* endp = 421 (char*)internal_memchr(p, '\0', len - (p - environ)); 422 if (!endp) // this entry isn't NUL terminated 423 return nullptr; 424 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match. 425 return p + namelen + 1; // point after = 426 p = endp + 1; 427 } 428 return nullptr; // Not found. 429 #else 430 #error "Unsupported platform" 431 #endif 432 } 433 434 #if !SANITIZER_FREEBSD 435 extern "C" { 436 SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end; 437 } 438 #endif 439 440 #if !SANITIZER_GO && !SANITIZER_FREEBSD 441 static void ReadNullSepFileToArray(const char *path, char ***arr, 442 int arr_size) { 443 char *buff; 444 uptr buff_size; 445 uptr buff_len; 446 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray"); 447 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) { 448 (*arr)[0] = nullptr; 449 return; 450 } 451 (*arr)[0] = buff; 452 int count, i; 453 for (count = 1, i = 1; ; i++) { 454 if (buff[i] == 0) { 455 if (buff[i+1] == 0) break; 456 (*arr)[count] = &buff[i+1]; 457 CHECK_LE(count, arr_size - 1); // FIXME: make this more flexible. 458 count++; 459 } 460 } 461 (*arr)[count] = nullptr; 462 } 463 #endif 464 465 static void GetArgsAndEnv(char ***argv, char ***envp) { 466 #if !SANITIZER_FREEBSD 467 #if !SANITIZER_GO 468 if (&__libc_stack_end) { 469 #endif 470 uptr* stack_end = (uptr*)__libc_stack_end; 471 int argc = *stack_end; 472 *argv = (char**)(stack_end + 1); 473 *envp = (char**)(stack_end + argc + 2); 474 #if !SANITIZER_GO 475 } else { 476 static const int kMaxArgv = 2000, kMaxEnvp = 2000; 477 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv); 478 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp); 479 } 480 #endif 481 #else 482 // On FreeBSD, retrieving the argument and environment arrays is done via the 483 // kern.ps_strings sysctl, which returns a pointer to a structure containing 484 // this information. See also <sys/exec.h>. 485 ps_strings *pss; 486 size_t sz = sizeof(pss); 487 if (sysctlbyname("kern.ps_strings", &pss, &sz, NULL, 0) == -1) { 488 Printf("sysctl kern.ps_strings failed\n"); 489 Die(); 490 } 491 *argv = pss->ps_argvstr; 492 *envp = pss->ps_envstr; 493 #endif 494 } 495 496 char **GetArgv() { 497 char **argv, **envp; 498 GetArgsAndEnv(&argv, &envp); 499 return argv; 500 } 501 502 void ReExec() { 503 char **argv, **envp; 504 GetArgsAndEnv(&argv, &envp); 505 uptr rv = internal_execve("/proc/self/exe", argv, envp); 506 int rverrno; 507 CHECK_EQ(internal_iserror(rv, &rverrno), true); 508 Printf("execve failed, errno %d\n", rverrno); 509 Die(); 510 } 511 512 enum MutexState { 513 MtxUnlocked = 0, 514 MtxLocked = 1, 515 MtxSleeping = 2 516 }; 517 518 BlockingMutex::BlockingMutex() { 519 internal_memset(this, 0, sizeof(*this)); 520 } 521 522 void BlockingMutex::Lock() { 523 CHECK_EQ(owner_, 0); 524 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 525 if (atomic_exchange(m, MtxLocked, memory_order_acquire) == MtxUnlocked) 526 return; 527 while (atomic_exchange(m, MtxSleeping, memory_order_acquire) != MtxUnlocked) { 528 #if SANITIZER_FREEBSD 529 _umtx_op(m, UMTX_OP_WAIT_UINT, MtxSleeping, 0, 0); 530 #else 531 internal_syscall(SYSCALL(futex), (uptr)m, FUTEX_WAIT, MtxSleeping, 0, 0, 0); 532 #endif 533 } 534 } 535 536 void BlockingMutex::Unlock() { 537 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 538 u32 v = atomic_exchange(m, MtxUnlocked, memory_order_relaxed); 539 CHECK_NE(v, MtxUnlocked); 540 if (v == MtxSleeping) { 541 #if SANITIZER_FREEBSD 542 _umtx_op(m, UMTX_OP_WAKE, 1, 0, 0); 543 #else 544 internal_syscall(SYSCALL(futex), (uptr)m, FUTEX_WAKE, 1, 0, 0, 0); 545 #endif 546 } 547 } 548 549 void BlockingMutex::CheckLocked() { 550 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_); 551 CHECK_NE(MtxUnlocked, atomic_load(m, memory_order_relaxed)); 552 } 553 554 // ----------------- sanitizer_linux.h 555 // The actual size of this structure is specified by d_reclen. 556 // Note that getdents64 uses a different structure format. We only provide the 557 // 32-bit syscall here. 558 struct linux_dirent { 559 #if SANITIZER_X32 || defined(__aarch64__) 560 u64 d_ino; 561 u64 d_off; 562 #else 563 unsigned long d_ino; 564 unsigned long d_off; 565 #endif 566 unsigned short d_reclen; 567 #ifdef __aarch64__ 568 unsigned char d_type; 569 #endif 570 char d_name[256]; 571 }; 572 573 // Syscall wrappers. 574 uptr internal_ptrace(int request, int pid, void *addr, void *data) { 575 return internal_syscall(SYSCALL(ptrace), request, pid, (uptr)addr, 576 (uptr)data); 577 } 578 579 uptr internal_waitpid(int pid, int *status, int options) { 580 return internal_syscall(SYSCALL(wait4), pid, (uptr)status, options, 581 0 /* rusage */); 582 } 583 584 uptr internal_getpid() { 585 return internal_syscall(SYSCALL(getpid)); 586 } 587 588 uptr internal_getppid() { 589 return internal_syscall(SYSCALL(getppid)); 590 } 591 592 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) { 593 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 594 return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count); 595 #else 596 return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count); 597 #endif 598 } 599 600 uptr internal_lseek(fd_t fd, OFF_T offset, int whence) { 601 return internal_syscall(SYSCALL(lseek), fd, offset, whence); 602 } 603 604 #if SANITIZER_LINUX 605 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) { 606 return internal_syscall(SYSCALL(prctl), option, arg2, arg3, arg4, arg5); 607 } 608 #endif 609 610 uptr internal_sigaltstack(const struct sigaltstack *ss, 611 struct sigaltstack *oss) { 612 return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss); 613 } 614 615 int internal_fork() { 616 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 617 return internal_syscall(SYSCALL(clone), SIGCHLD, 0); 618 #else 619 return internal_syscall(SYSCALL(fork)); 620 #endif 621 } 622 623 #if SANITIZER_LINUX 624 #define SA_RESTORER 0x04000000 625 // Doesn't set sa_restorer if the caller did not set it, so use with caution 626 //(see below). 627 int internal_sigaction_norestorer(int signum, const void *act, void *oldact) { 628 __sanitizer_kernel_sigaction_t k_act, k_oldact; 629 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t)); 630 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t)); 631 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act; 632 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact; 633 if (u_act) { 634 k_act.handler = u_act->handler; 635 k_act.sigaction = u_act->sigaction; 636 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask, 637 sizeof(__sanitizer_kernel_sigset_t)); 638 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL). 639 k_act.sa_flags = u_act->sa_flags | SA_RESTORER; 640 // FIXME: most often sa_restorer is unset, however the kernel requires it 641 // to point to a valid signal restorer that calls the rt_sigreturn syscall. 642 // If sa_restorer passed to the kernel is NULL, the program may crash upon 643 // signal delivery or fail to unwind the stack in the signal handler. 644 // libc implementation of sigaction() passes its own restorer to 645 // rt_sigaction, so we need to do the same (we'll need to reimplement the 646 // restorers; for x86_64 the restorer address can be obtained from 647 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact). 648 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 649 k_act.sa_restorer = u_act->sa_restorer; 650 #endif 651 } 652 653 uptr result = internal_syscall(SYSCALL(rt_sigaction), (uptr)signum, 654 (uptr)(u_act ? &k_act : nullptr), 655 (uptr)(u_oldact ? &k_oldact : nullptr), 656 (uptr)sizeof(__sanitizer_kernel_sigset_t)); 657 658 if ((result == 0) && u_oldact) { 659 u_oldact->handler = k_oldact.handler; 660 u_oldact->sigaction = k_oldact.sigaction; 661 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask, 662 sizeof(__sanitizer_kernel_sigset_t)); 663 u_oldact->sa_flags = k_oldact.sa_flags; 664 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 665 u_oldact->sa_restorer = k_oldact.sa_restorer; 666 #endif 667 } 668 return result; 669 } 670 671 // Invokes sigaction via a raw syscall with a restorer, but does not support 672 // all platforms yet. 673 // We disable for Go simply because we have not yet added to buildgo.sh. 674 #if defined(__x86_64__) && !SANITIZER_GO 675 int internal_sigaction_syscall(int signum, const void *act, void *oldact) { 676 if (act == nullptr) 677 return internal_sigaction_norestorer(signum, act, oldact); 678 __sanitizer_sigaction u_adjust; 679 internal_memcpy(&u_adjust, act, sizeof(u_adjust)); 680 #if !SANITIZER_ANDROID || !SANITIZER_MIPS32 681 if (u_adjust.sa_restorer == nullptr) { 682 u_adjust.sa_restorer = internal_sigreturn; 683 } 684 #endif 685 return internal_sigaction_norestorer(signum, (const void *)&u_adjust, 686 oldact); 687 } 688 #endif // defined(__x86_64__) && !SANITIZER_GO 689 #endif // SANITIZER_LINUX 690 691 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set, 692 __sanitizer_sigset_t *oldset) { 693 #if SANITIZER_FREEBSD 694 return internal_syscall(SYSCALL(sigprocmask), how, set, oldset); 695 #else 696 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 697 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset; 698 return internal_syscall(SYSCALL(rt_sigprocmask), (uptr)how, 699 (uptr)&k_set->sig[0], (uptr)&k_oldset->sig[0], 700 sizeof(__sanitizer_kernel_sigset_t)); 701 #endif 702 } 703 704 void internal_sigfillset(__sanitizer_sigset_t *set) { 705 internal_memset(set, 0xff, sizeof(*set)); 706 } 707 708 void internal_sigemptyset(__sanitizer_sigset_t *set) { 709 internal_memset(set, 0, sizeof(*set)); 710 } 711 712 #if SANITIZER_LINUX 713 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 714 signum -= 1; 715 CHECK_GE(signum, 0); 716 CHECK_LT(signum, sizeof(*set) * 8); 717 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 718 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 719 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 720 k_set->sig[idx] &= ~(1 << bit); 721 } 722 723 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 724 signum -= 1; 725 CHECK_GE(signum, 0); 726 CHECK_LT(signum, sizeof(*set) * 8); 727 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 728 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 729 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 730 return k_set->sig[idx] & (1 << bit); 731 } 732 #endif // SANITIZER_LINUX 733 734 // ThreadLister implementation. 735 ThreadLister::ThreadLister(int pid) 736 : pid_(pid), 737 descriptor_(-1), 738 buffer_(4096), 739 error_(true), 740 entry_((struct linux_dirent *)buffer_.data()), 741 bytes_read_(0) { 742 char task_directory_path[80]; 743 internal_snprintf(task_directory_path, sizeof(task_directory_path), 744 "/proc/%d/task/", pid); 745 uptr openrv = internal_open(task_directory_path, O_RDONLY | O_DIRECTORY); 746 if (internal_iserror(openrv)) { 747 error_ = true; 748 Report("Can't open /proc/%d/task for reading.\n", pid); 749 } else { 750 error_ = false; 751 descriptor_ = openrv; 752 } 753 } 754 755 int ThreadLister::GetNextTID() { 756 int tid = -1; 757 do { 758 if (error_) 759 return -1; 760 if ((char *)entry_ >= &buffer_[bytes_read_] && !GetDirectoryEntries()) 761 return -1; 762 if (entry_->d_ino != 0 && entry_->d_name[0] >= '0' && 763 entry_->d_name[0] <= '9') { 764 // Found a valid tid. 765 tid = (int)internal_atoll(entry_->d_name); 766 } 767 entry_ = (struct linux_dirent *)(((char *)entry_) + entry_->d_reclen); 768 } while (tid < 0); 769 return tid; 770 } 771 772 void ThreadLister::Reset() { 773 if (error_ || descriptor_ < 0) 774 return; 775 internal_lseek(descriptor_, 0, SEEK_SET); 776 } 777 778 ThreadLister::~ThreadLister() { 779 if (descriptor_ >= 0) 780 internal_close(descriptor_); 781 } 782 783 bool ThreadLister::error() { return error_; } 784 785 bool ThreadLister::GetDirectoryEntries() { 786 CHECK_GE(descriptor_, 0); 787 CHECK_NE(error_, true); 788 bytes_read_ = internal_getdents(descriptor_, 789 (struct linux_dirent *)buffer_.data(), 790 buffer_.size()); 791 if (internal_iserror(bytes_read_)) { 792 Report("Can't read directory entries from /proc/%d/task.\n", pid_); 793 error_ = true; 794 return false; 795 } else if (bytes_read_ == 0) { 796 return false; 797 } 798 entry_ = (struct linux_dirent *)buffer_.data(); 799 return true; 800 } 801 802 uptr GetPageSize() { 803 // Android post-M sysconf(_SC_PAGESIZE) crashes if called from .preinit_array. 804 #if SANITIZER_ANDROID 805 return 4096; 806 #elif SANITIZER_LINUX && (defined(__x86_64__) || defined(__i386__)) 807 return EXEC_PAGESIZE; 808 #else 809 return sysconf(_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy. 810 #endif 811 } 812 813 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) { 814 #if SANITIZER_FREEBSD 815 const int Mib[] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1 }; 816 const char *default_module_name = "kern.proc.pathname"; 817 size_t Size = buf_len; 818 bool IsErr = (sysctl(Mib, ARRAY_SIZE(Mib), buf, &Size, NULL, 0) != 0); 819 int readlink_error = IsErr ? errno : 0; 820 uptr module_name_len = Size; 821 #else 822 const char *default_module_name = "/proc/self/exe"; 823 uptr module_name_len = internal_readlink( 824 default_module_name, buf, buf_len); 825 int readlink_error; 826 bool IsErr = internal_iserror(module_name_len, &readlink_error); 827 #endif 828 if (IsErr) { 829 // We can't read binary name for some reason, assume it's unknown. 830 Report("WARNING: reading executable name failed with errno %d, " 831 "some stack frames may not be symbolized\n", readlink_error); 832 module_name_len = internal_snprintf(buf, buf_len, "%s", 833 default_module_name); 834 CHECK_LT(module_name_len, buf_len); 835 } 836 return module_name_len; 837 } 838 839 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) { 840 #if SANITIZER_LINUX 841 char *tmpbuf; 842 uptr tmpsize; 843 uptr tmplen; 844 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen, 845 1024 * 1024)) { 846 internal_strncpy(buf, tmpbuf, buf_len); 847 UnmapOrDie(tmpbuf, tmpsize); 848 return internal_strlen(buf); 849 } 850 #endif 851 return ReadBinaryName(buf, buf_len); 852 } 853 854 // Match full names of the form /path/to/base_name{-,.}* 855 bool LibraryNameIs(const char *full_name, const char *base_name) { 856 const char *name = full_name; 857 // Strip path. 858 while (*name != '\0') name++; 859 while (name > full_name && *name != '/') name--; 860 if (*name == '/') name++; 861 uptr base_name_length = internal_strlen(base_name); 862 if (internal_strncmp(name, base_name, base_name_length)) return false; 863 return (name[base_name_length] == '-' || name[base_name_length] == '.'); 864 } 865 866 #if !SANITIZER_ANDROID 867 // Call cb for each region mapped by map. 868 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) { 869 CHECK_NE(map, nullptr); 870 #if !SANITIZER_FREEBSD 871 typedef ElfW(Phdr) Elf_Phdr; 872 typedef ElfW(Ehdr) Elf_Ehdr; 873 #endif // !SANITIZER_FREEBSD 874 char *base = (char *)map->l_addr; 875 Elf_Ehdr *ehdr = (Elf_Ehdr *)base; 876 char *phdrs = base + ehdr->e_phoff; 877 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize; 878 879 // Find the segment with the minimum base so we can "relocate" the p_vaddr 880 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC 881 // objects have a non-zero base. 882 uptr preferred_base = (uptr)-1; 883 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 884 Elf_Phdr *phdr = (Elf_Phdr *)iter; 885 if (phdr->p_type == PT_LOAD && preferred_base > (uptr)phdr->p_vaddr) 886 preferred_base = (uptr)phdr->p_vaddr; 887 } 888 889 // Compute the delta from the real base to get a relocation delta. 890 sptr delta = (uptr)base - preferred_base; 891 // Now we can figure out what the loader really mapped. 892 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 893 Elf_Phdr *phdr = (Elf_Phdr *)iter; 894 if (phdr->p_type == PT_LOAD) { 895 uptr seg_start = phdr->p_vaddr + delta; 896 uptr seg_end = seg_start + phdr->p_memsz; 897 // None of these values are aligned. We consider the ragged edges of the 898 // load command as defined, since they are mapped from the file. 899 seg_start = RoundDownTo(seg_start, GetPageSizeCached()); 900 seg_end = RoundUpTo(seg_end, GetPageSizeCached()); 901 cb((void *)seg_start, seg_end - seg_start); 902 } 903 } 904 } 905 #endif 906 907 #if defined(__x86_64__) && SANITIZER_LINUX 908 // We cannot use glibc's clone wrapper, because it messes with the child 909 // task's TLS. It writes the PID and TID of the child task to its thread 910 // descriptor, but in our case the child task shares the thread descriptor with 911 // the parent (because we don't know how to allocate a new thread 912 // descriptor to keep glibc happy). So the stock version of clone(), when 913 // used with CLONE_VM, would end up corrupting the parent's thread descriptor. 914 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 915 int *parent_tidptr, void *newtls, int *child_tidptr) { 916 long long res; 917 if (!fn || !child_stack) 918 return -EINVAL; 919 CHECK_EQ(0, (uptr)child_stack % 16); 920 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 921 ((unsigned long long *)child_stack)[0] = (uptr)fn; 922 ((unsigned long long *)child_stack)[1] = (uptr)arg; 923 register void *r8 __asm__("r8") = newtls; 924 register int *r10 __asm__("r10") = child_tidptr; 925 __asm__ __volatile__( 926 /* %rax = syscall(%rax = SYSCALL(clone), 927 * %rdi = flags, 928 * %rsi = child_stack, 929 * %rdx = parent_tidptr, 930 * %r8 = new_tls, 931 * %r10 = child_tidptr) 932 */ 933 "syscall\n" 934 935 /* if (%rax != 0) 936 * return; 937 */ 938 "testq %%rax,%%rax\n" 939 "jnz 1f\n" 940 941 /* In the child. Terminate unwind chain. */ 942 // XXX: We should also terminate the CFI unwind chain 943 // here. Unfortunately clang 3.2 doesn't support the 944 // necessary CFI directives, so we skip that part. 945 "xorq %%rbp,%%rbp\n" 946 947 /* Call "fn(arg)". */ 948 "popq %%rax\n" 949 "popq %%rdi\n" 950 "call *%%rax\n" 951 952 /* Call _exit(%rax). */ 953 "movq %%rax,%%rdi\n" 954 "movq %2,%%rax\n" 955 "syscall\n" 956 957 /* Return to parent. */ 958 "1:\n" 959 : "=a" (res) 960 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 961 "S"(child_stack), 962 "D"(flags), 963 "d"(parent_tidptr), 964 "r"(r8), 965 "r"(r10) 966 : "rsp", "memory", "r11", "rcx"); 967 return res; 968 } 969 #elif defined(__mips__) 970 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 971 int *parent_tidptr, void *newtls, int *child_tidptr) { 972 long long res; 973 if (!fn || !child_stack) 974 return -EINVAL; 975 CHECK_EQ(0, (uptr)child_stack % 16); 976 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 977 ((unsigned long long *)child_stack)[0] = (uptr)fn; 978 ((unsigned long long *)child_stack)[1] = (uptr)arg; 979 register void *a3 __asm__("$7") = newtls; 980 register int *a4 __asm__("$8") = child_tidptr; 981 // We don't have proper CFI directives here because it requires alot of code 982 // for very marginal benefits. 983 __asm__ __volatile__( 984 /* $v0 = syscall($v0 = __NR_clone, 985 * $a0 = flags, 986 * $a1 = child_stack, 987 * $a2 = parent_tidptr, 988 * $a3 = new_tls, 989 * $a4 = child_tidptr) 990 */ 991 ".cprestore 16;\n" 992 "move $4,%1;\n" 993 "move $5,%2;\n" 994 "move $6,%3;\n" 995 "move $7,%4;\n" 996 /* Store the fifth argument on stack 997 * if we are using 32-bit abi. 998 */ 999 #if SANITIZER_WORDSIZE == 32 1000 "lw %5,16($29);\n" 1001 #else 1002 "move $8,%5;\n" 1003 #endif 1004 "li $2,%6;\n" 1005 "syscall;\n" 1006 1007 /* if ($v0 != 0) 1008 * return; 1009 */ 1010 "bnez $2,1f;\n" 1011 1012 /* Call "fn(arg)". */ 1013 #if SANITIZER_WORDSIZE == 32 1014 #ifdef __BIG_ENDIAN__ 1015 "lw $25,4($29);\n" 1016 "lw $4,12($29);\n" 1017 #else 1018 "lw $25,0($29);\n" 1019 "lw $4,8($29);\n" 1020 #endif 1021 #else 1022 "ld $25,0($29);\n" 1023 "ld $4,8($29);\n" 1024 #endif 1025 "jal $25;\n" 1026 1027 /* Call _exit($v0). */ 1028 "move $4,$2;\n" 1029 "li $2,%7;\n" 1030 "syscall;\n" 1031 1032 /* Return to parent. */ 1033 "1:\n" 1034 : "=r" (res) 1035 : "r"(flags), 1036 "r"(child_stack), 1037 "r"(parent_tidptr), 1038 "r"(a3), 1039 "r"(a4), 1040 "i"(__NR_clone), 1041 "i"(__NR_exit) 1042 : "memory", "$29" ); 1043 return res; 1044 } 1045 #elif defined(__aarch64__) 1046 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1047 int *parent_tidptr, void *newtls, int *child_tidptr) { 1048 long long res; 1049 if (!fn || !child_stack) 1050 return -EINVAL; 1051 CHECK_EQ(0, (uptr)child_stack % 16); 1052 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1053 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1054 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1055 1056 register int (*__fn)(void *) __asm__("x0") = fn; 1057 register void *__stack __asm__("x1") = child_stack; 1058 register int __flags __asm__("x2") = flags; 1059 register void *__arg __asm__("x3") = arg; 1060 register int *__ptid __asm__("x4") = parent_tidptr; 1061 register void *__tls __asm__("x5") = newtls; 1062 register int *__ctid __asm__("x6") = child_tidptr; 1063 1064 __asm__ __volatile__( 1065 "mov x0,x2\n" /* flags */ 1066 "mov x2,x4\n" /* ptid */ 1067 "mov x3,x5\n" /* tls */ 1068 "mov x4,x6\n" /* ctid */ 1069 "mov x8,%9\n" /* clone */ 1070 1071 "svc 0x0\n" 1072 1073 /* if (%r0 != 0) 1074 * return %r0; 1075 */ 1076 "cmp x0, #0\n" 1077 "bne 1f\n" 1078 1079 /* In the child, now. Call "fn(arg)". */ 1080 "ldp x1, x0, [sp], #16\n" 1081 "blr x1\n" 1082 1083 /* Call _exit(%r0). */ 1084 "mov x8, %10\n" 1085 "svc 0x0\n" 1086 "1:\n" 1087 1088 : "=r" (res) 1089 : "i"(-EINVAL), 1090 "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg), 1091 "r"(__ptid), "r"(__tls), "r"(__ctid), 1092 "i"(__NR_clone), "i"(__NR_exit) 1093 : "x30", "memory"); 1094 return res; 1095 } 1096 #elif defined(__powerpc64__) 1097 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1098 int *parent_tidptr, void *newtls, int *child_tidptr) { 1099 long long res; 1100 /* Stack frame offsets. */ 1101 #if _CALL_ELF != 2 1102 #define FRAME_MIN_SIZE 112 1103 #define FRAME_TOC_SAVE 40 1104 #else 1105 #define FRAME_MIN_SIZE 32 1106 #define FRAME_TOC_SAVE 24 1107 #endif 1108 if (!fn || !child_stack) 1109 return -EINVAL; 1110 CHECK_EQ(0, (uptr)child_stack % 16); 1111 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1112 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1113 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1114 1115 register int (*__fn)(void *) __asm__("r3") = fn; 1116 register void *__cstack __asm__("r4") = child_stack; 1117 register int __flags __asm__("r5") = flags; 1118 register void * __arg __asm__("r6") = arg; 1119 register int * __ptidptr __asm__("r7") = parent_tidptr; 1120 register void * __newtls __asm__("r8") = newtls; 1121 register int * __ctidptr __asm__("r9") = child_tidptr; 1122 1123 __asm__ __volatile__( 1124 /* fn, arg, child_stack are saved acrVoss the syscall */ 1125 "mr 28, %5\n\t" 1126 "mr 29, %6\n\t" 1127 "mr 27, %8\n\t" 1128 1129 /* syscall 1130 r3 == flags 1131 r4 == child_stack 1132 r5 == parent_tidptr 1133 r6 == newtls 1134 r7 == child_tidptr */ 1135 "mr 3, %7\n\t" 1136 "mr 5, %9\n\t" 1137 "mr 6, %10\n\t" 1138 "mr 7, %11\n\t" 1139 "li 0, %3\n\t" 1140 "sc\n\t" 1141 1142 /* Test if syscall was successful */ 1143 "cmpdi cr1, 3, 0\n\t" 1144 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t" 1145 "bne- cr1, 1f\n\t" 1146 1147 /* Do the function call */ 1148 "std 2, %13(1)\n\t" 1149 #if _CALL_ELF != 2 1150 "ld 0, 0(28)\n\t" 1151 "ld 2, 8(28)\n\t" 1152 "mtctr 0\n\t" 1153 #else 1154 "mr 12, 28\n\t" 1155 "mtctr 12\n\t" 1156 #endif 1157 "mr 3, 27\n\t" 1158 "bctrl\n\t" 1159 "ld 2, %13(1)\n\t" 1160 1161 /* Call _exit(r3) */ 1162 "li 0, %4\n\t" 1163 "sc\n\t" 1164 1165 /* Return to parent */ 1166 "1:\n\t" 1167 "mr %0, 3\n\t" 1168 : "=r" (res) 1169 : "0" (-1), "i" (EINVAL), 1170 "i" (__NR_clone), "i" (__NR_exit), 1171 "r" (__fn), "r" (__cstack), "r" (__flags), 1172 "r" (__arg), "r" (__ptidptr), "r" (__newtls), 1173 "r" (__ctidptr), "i" (FRAME_MIN_SIZE), "i" (FRAME_TOC_SAVE) 1174 : "cr0", "cr1", "memory", "ctr", 1175 "r0", "r29", "r27", "r28"); 1176 return res; 1177 } 1178 #endif // defined(__x86_64__) && SANITIZER_LINUX 1179 1180 #if SANITIZER_ANDROID 1181 #if __ANDROID_API__ < 21 1182 extern "C" __attribute__((weak)) int dl_iterate_phdr( 1183 int (*)(struct dl_phdr_info *, size_t, void *), void *); 1184 #endif 1185 1186 static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size, 1187 void *data) { 1188 // Any name starting with "lib" indicates a bug in L where library base names 1189 // are returned instead of paths. 1190 if (info->dlpi_name && info->dlpi_name[0] == 'l' && 1191 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') { 1192 *(bool *)data = true; 1193 return 1; 1194 } 1195 return 0; 1196 } 1197 1198 static atomic_uint32_t android_api_level; 1199 1200 static AndroidApiLevel AndroidDetectApiLevel() { 1201 if (!&dl_iterate_phdr) 1202 return ANDROID_KITKAT; // K or lower 1203 bool base_name_seen = false; 1204 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen); 1205 if (base_name_seen) 1206 return ANDROID_LOLLIPOP_MR1; // L MR1 1207 return ANDROID_POST_LOLLIPOP; // post-L 1208 // Plain L (API level 21) is completely broken wrt ASan and not very 1209 // interesting to detect. 1210 } 1211 1212 AndroidApiLevel AndroidGetApiLevel() { 1213 AndroidApiLevel level = 1214 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed); 1215 if (level) return level; 1216 level = AndroidDetectApiLevel(); 1217 atomic_store(&android_api_level, level, memory_order_relaxed); 1218 return level; 1219 } 1220 1221 #endif 1222 1223 bool IsHandledDeadlySignal(int signum) { 1224 if (common_flags()->handle_abort && signum == SIGABRT) 1225 return true; 1226 if (common_flags()->handle_sigill && signum == SIGILL) 1227 return true; 1228 if (common_flags()->handle_sigfpe && signum == SIGFPE) 1229 return true; 1230 return (signum == SIGSEGV || signum == SIGBUS) && common_flags()->handle_segv; 1231 } 1232 1233 #ifndef SANITIZER_GO 1234 void *internal_start_thread(void(*func)(void *arg), void *arg) { 1235 // Start the thread with signals blocked, otherwise it can steal user signals. 1236 __sanitizer_sigset_t set, old; 1237 internal_sigfillset(&set); 1238 #if SANITIZER_LINUX && !SANITIZER_ANDROID 1239 // Glibc uses SIGSETXID signal during setuid call. If this signal is blocked 1240 // on any thread, setuid call hangs (see test/tsan/setuid.c). 1241 internal_sigdelset(&set, 33); 1242 #endif 1243 internal_sigprocmask(SIG_SETMASK, &set, &old); 1244 void *th; 1245 real_pthread_create(&th, nullptr, (void*(*)(void *arg))func, arg); 1246 internal_sigprocmask(SIG_SETMASK, &old, nullptr); 1247 return th; 1248 } 1249 1250 void internal_join_thread(void *th) { 1251 real_pthread_join(th, nullptr); 1252 } 1253 #else 1254 void *internal_start_thread(void (*func)(void *), void *arg) { return 0; } 1255 1256 void internal_join_thread(void *th) {} 1257 #endif 1258 1259 #if defined(__aarch64__) 1260 // Android headers in the older NDK releases miss this definition. 1261 struct __sanitizer_esr_context { 1262 struct _aarch64_ctx head; 1263 uint64_t esr; 1264 }; 1265 1266 static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) { 1267 static const u32 kEsrMagic = 0x45535201; 1268 u8 *aux = ucontext->uc_mcontext.__reserved; 1269 while (true) { 1270 _aarch64_ctx *ctx = (_aarch64_ctx *)aux; 1271 if (ctx->size == 0) break; 1272 if (ctx->magic == kEsrMagic) { 1273 *esr = ((__sanitizer_esr_context *)ctx)->esr; 1274 return true; 1275 } 1276 aux += ctx->size; 1277 } 1278 return false; 1279 } 1280 #endif 1281 1282 SignalContext::WriteFlag SignalContext::GetWriteFlag(void *context) { 1283 ucontext_t *ucontext = (ucontext_t *)context; 1284 #if defined(__x86_64__) || defined(__i386__) 1285 static const uptr PF_WRITE = 1U << 1; 1286 #if SANITIZER_FREEBSD 1287 uptr err = ucontext->uc_mcontext.mc_err; 1288 #else 1289 uptr err = ucontext->uc_mcontext.gregs[REG_ERR]; 1290 #endif 1291 return err & PF_WRITE ? WRITE : READ; 1292 #elif defined(__arm__) 1293 static const uptr FSR_WRITE = 1U << 11; 1294 uptr fsr = ucontext->uc_mcontext.error_code; 1295 // FSR bits 5:0 describe the abort type, and are never 0 (or so it seems). 1296 // Zero FSR indicates an older kernel that does not pass this information to 1297 // the userspace. 1298 if (fsr == 0) return UNKNOWN; 1299 return fsr & FSR_WRITE ? WRITE : READ; 1300 #elif defined(__aarch64__) 1301 static const u64 ESR_ELx_WNR = 1U << 6; 1302 u64 esr; 1303 if (!Aarch64GetESR(ucontext, &esr)) return UNKNOWN; 1304 return esr & ESR_ELx_WNR ? WRITE : READ; 1305 #else 1306 (void)ucontext; 1307 return UNKNOWN; // FIXME: Implement. 1308 #endif 1309 } 1310 1311 void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) { 1312 #if defined(__arm__) 1313 ucontext_t *ucontext = (ucontext_t*)context; 1314 *pc = ucontext->uc_mcontext.arm_pc; 1315 *bp = ucontext->uc_mcontext.arm_fp; 1316 *sp = ucontext->uc_mcontext.arm_sp; 1317 #elif defined(__aarch64__) 1318 ucontext_t *ucontext = (ucontext_t*)context; 1319 *pc = ucontext->uc_mcontext.pc; 1320 *bp = ucontext->uc_mcontext.regs[29]; 1321 *sp = ucontext->uc_mcontext.sp; 1322 #elif defined(__hppa__) 1323 ucontext_t *ucontext = (ucontext_t*)context; 1324 *pc = ucontext->uc_mcontext.sc_iaoq[0]; 1325 /* GCC uses %r3 whenever a frame pointer is needed. */ 1326 *bp = ucontext->uc_mcontext.sc_gr[3]; 1327 *sp = ucontext->uc_mcontext.sc_gr[30]; 1328 #elif defined(__x86_64__) 1329 # if SANITIZER_FREEBSD 1330 ucontext_t *ucontext = (ucontext_t*)context; 1331 *pc = ucontext->uc_mcontext.mc_rip; 1332 *bp = ucontext->uc_mcontext.mc_rbp; 1333 *sp = ucontext->uc_mcontext.mc_rsp; 1334 # else 1335 ucontext_t *ucontext = (ucontext_t*)context; 1336 *pc = ucontext->uc_mcontext.gregs[REG_RIP]; 1337 *bp = ucontext->uc_mcontext.gregs[REG_RBP]; 1338 *sp = ucontext->uc_mcontext.gregs[REG_RSP]; 1339 # endif 1340 #elif defined(__i386__) 1341 # if SANITIZER_FREEBSD 1342 ucontext_t *ucontext = (ucontext_t*)context; 1343 *pc = ucontext->uc_mcontext.mc_eip; 1344 *bp = ucontext->uc_mcontext.mc_ebp; 1345 *sp = ucontext->uc_mcontext.mc_esp; 1346 # else 1347 ucontext_t *ucontext = (ucontext_t*)context; 1348 *pc = ucontext->uc_mcontext.gregs[REG_EIP]; 1349 *bp = ucontext->uc_mcontext.gregs[REG_EBP]; 1350 *sp = ucontext->uc_mcontext.gregs[REG_ESP]; 1351 # endif 1352 #elif defined(__powerpc__) || defined(__powerpc64__) 1353 ucontext_t *ucontext = (ucontext_t*)context; 1354 *pc = ucontext->uc_mcontext.regs->nip; 1355 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1]; 1356 // The powerpc{,64}-linux ABIs do not specify r31 as the frame 1357 // pointer, but GCC always uses r31 when we need a frame pointer. 1358 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31]; 1359 #elif defined(__sparc__) 1360 ucontext_t *ucontext = (ucontext_t*)context; 1361 uptr *stk_ptr; 1362 # if defined (__arch64__) 1363 *pc = ucontext->uc_mcontext.mc_gregs[MC_PC]; 1364 *sp = ucontext->uc_mcontext.mc_gregs[MC_O6]; 1365 stk_ptr = (uptr *) (*sp + 2047); 1366 *bp = stk_ptr[15]; 1367 # else 1368 *pc = ucontext->uc_mcontext.gregs[REG_PC]; 1369 *sp = ucontext->uc_mcontext.gregs[REG_O6]; 1370 stk_ptr = (uptr *) *sp; 1371 *bp = stk_ptr[15]; 1372 # endif 1373 #elif defined(__mips__) 1374 ucontext_t *ucontext = (ucontext_t*)context; 1375 *pc = ucontext->uc_mcontext.pc; 1376 *bp = ucontext->uc_mcontext.gregs[30]; 1377 *sp = ucontext->uc_mcontext.gregs[29]; 1378 #elif defined(__s390__) 1379 ucontext_t *ucontext = (ucontext_t*)context; 1380 # if defined(__s390x__) 1381 *pc = ucontext->uc_mcontext.psw.addr; 1382 # else 1383 *pc = ucontext->uc_mcontext.psw.addr & 0x7fffffff; 1384 # endif 1385 *bp = ucontext->uc_mcontext.gregs[11]; 1386 *sp = ucontext->uc_mcontext.gregs[15]; 1387 #else 1388 # error "Unsupported arch" 1389 #endif 1390 } 1391 1392 void MaybeReexec() { 1393 // No need to re-exec on Linux. 1394 } 1395 1396 } // namespace __sanitizer 1397 1398 #endif // SANITIZER_FREEBSD || SANITIZER_LINUX 1399
