1//===-- sanitizer_linux.cpp -----------------------------------------------===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8// 9// This file is shared between AddressSanitizer and ThreadSanitizer 10// run-time libraries and implements linux-specific functions from 11// sanitizer_libc.h. 12//===----------------------------------------------------------------------===// 13 14#include "sanitizer_platform.h" 15 16#if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \ 17 SANITIZER_SOLARIS 18 19#include "sanitizer_common.h" 20#include "sanitizer_flags.h" 21#include "sanitizer_getauxval.h" 22#include "sanitizer_internal_defs.h" 23#include "sanitizer_libc.h" 24#include "sanitizer_linux.h" 25#include "sanitizer_mutex.h" 26#include "sanitizer_placement_new.h" 27#include "sanitizer_procmaps.h" 28 29#if SANITIZER_LINUX && !SANITIZER_GO 30#include <asm/param.h> 31#endif 32 33// For mips64, syscall(__NR_stat) fills the buffer in the 'struct kernel_stat' 34// format. Struct kernel_stat is defined as 'struct stat' in asm/stat.h. To 35// access stat from asm/stat.h, without conflicting with definition in 36// sys/stat.h, we use this trick. 37#if SANITIZER_LINUX 38#if defined(__mips64) 39#include <asm/unistd.h> 40#include <sys/types.h> 41#define stat kernel_stat 42#if SANITIZER_GO 43#undef st_atime 44#undef st_mtime 45#undef st_ctime 46#define st_atime st_atim 47#define st_mtime st_mtim 48#define st_ctime st_ctim 49#endif 50#include <asm/stat.h> 51#undef stat 52#endif 53#endif 54 55#if SANITIZER_NETBSD 56#include <lwp.h> 57#endif 58 59#include <dlfcn.h> 60#include <errno.h> 61#include <fcntl.h> 62#include <link.h> 63#include <pthread.h> 64#include <sched.h> 65#include <signal.h> 66#include <sys/mman.h> 67#include <sys/param.h> 68#if !SANITIZER_SOLARIS 69#include <sys/ptrace.h> 70#endif 71#include <sys/resource.h> 72#include <sys/stat.h> 73#include <sys/syscall.h> 74#include <sys/time.h> 75#include <sys/types.h> 76#include <ucontext.h> 77#include <unistd.h> 78 79#if SANITIZER_LINUX 80#include <sys/utsname.h> 81#endif 82 83#if SANITIZER_LINUX && !SANITIZER_ANDROID 84#include <sys/personality.h> 85#endif 86 87#if SANITIZER_FREEBSD 88#include <sys/exec.h> 89#include <sys/sysctl.h> 90#include <machine/atomic.h> 91extern "C" { 92// <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on 93// FreeBSD 9.2 and 10.0. 94#include <sys/umtx.h> 95} 96#include <sys/thr.h> 97#endif // SANITIZER_FREEBSD 98 99#if SANITIZER_NETBSD 100#include <limits.h> // For NAME_MAX 101#include <sys/sysctl.h> 102#include <sys/exec.h> 103extern struct ps_strings *__ps_strings; 104#endif // SANITIZER_NETBSD 105 106#if SANITIZER_SOLARIS 107#include <stdlib.h> 108#include <thread.h> 109#define environ _environ 110#endif 111 112extern char **environ; 113 114#if SANITIZER_LINUX 115// <linux/time.h> 116struct kernel_timeval { 117 long tv_sec; 118 long tv_usec; 119}; 120 121// <linux/futex.h> is broken on some linux distributions. 122const int FUTEX_WAIT = 0; 123const int FUTEX_WAKE = 1; 124const int FUTEX_PRIVATE_FLAG = 128; 125const int FUTEX_WAIT_PRIVATE = FUTEX_WAIT | FUTEX_PRIVATE_FLAG; 126const int FUTEX_WAKE_PRIVATE = FUTEX_WAKE | FUTEX_PRIVATE_FLAG; 127#endif // SANITIZER_LINUX 128 129// Are we using 32-bit or 64-bit Linux syscalls? 130// x32 (which defines __x86_64__) has SANITIZER_WORDSIZE == 32 131// but it still needs to use 64-bit syscalls. 132#if SANITIZER_LINUX && (defined(__x86_64__) || defined(__powerpc64__) || \ 133 SANITIZER_WORDSIZE == 64) 134# define SANITIZER_LINUX_USES_64BIT_SYSCALLS 1 135#else 136# define SANITIZER_LINUX_USES_64BIT_SYSCALLS 0 137#endif 138 139// Note : FreeBSD had implemented both 140// Linux apis, available from 141// future 12.x version most likely 142#if SANITIZER_LINUX && defined(__NR_getrandom) 143# if !defined(GRND_NONBLOCK) 144# define GRND_NONBLOCK 1 145# endif 146# define SANITIZER_USE_GETRANDOM 1 147#else 148# define SANITIZER_USE_GETRANDOM 0 149#endif // SANITIZER_LINUX && defined(__NR_getrandom) 150 151#if SANITIZER_FREEBSD && __FreeBSD_version >= 1200000 152# define SANITIZER_USE_GETENTROPY 1 153#else 154# define SANITIZER_USE_GETENTROPY 0 155#endif 156 157namespace __sanitizer { 158 159void SetSigProcMask(__sanitizer_sigset_t *set, __sanitizer_sigset_t *old) { 160 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, set, old)); 161} 162 163ScopedBlockSignals::ScopedBlockSignals(__sanitizer_sigset_t *copy) { 164 __sanitizer_sigset_t set; 165 internal_sigfillset(&set); 166# if SANITIZER_LINUX && !SANITIZER_ANDROID 167 // Glibc uses SIGSETXID signal during setuid call. If this signal is blocked 168 // on any thread, setuid call hangs. 169 // See test/sanitizer_common/TestCases/Linux/setuid.c. 170 internal_sigdelset(&set, 33); 171# endif 172 SetSigProcMask(&set, &saved_); 173 if (copy) 174 internal_memcpy(copy, &saved_, sizeof(saved_)); 175} 176 177ScopedBlockSignals::~ScopedBlockSignals() { SetSigProcMask(&saved_, nullptr); } 178 179# if SANITIZER_LINUX && defined(__x86_64__) 180# include "sanitizer_syscall_linux_x86_64.inc" 181# elif SANITIZER_LINUX && SANITIZER_RISCV64 182# include "sanitizer_syscall_linux_riscv64.inc" 183# elif SANITIZER_LINUX && defined(__aarch64__) 184# include "sanitizer_syscall_linux_aarch64.inc" 185# elif SANITIZER_LINUX && defined(__arm__) 186# include "sanitizer_syscall_linux_arm.inc" 187# elif SANITIZER_LINUX && defined(__hexagon__) 188# include "sanitizer_syscall_linux_hexagon.inc" 189# else 190# include "sanitizer_syscall_generic.inc" 191# endif 192 193// --------------- sanitizer_libc.h 194#if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 195#if !SANITIZER_S390 196uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd, 197 u64 offset) { 198#if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 199 return internal_syscall(SYSCALL(mmap), (uptr)addr, length, prot, flags, fd, 200 offset); 201#else 202 // mmap2 specifies file offset in 4096-byte units. 203 CHECK(IsAligned(offset, 4096)); 204 return internal_syscall(SYSCALL(mmap2), addr, length, prot, flags, fd, 205 offset / 4096); 206#endif 207} 208#endif // !SANITIZER_S390 209 210uptr internal_munmap(void *addr, uptr length) { 211 return internal_syscall(SYSCALL(munmap), (uptr)addr, length); 212} 213 214#if SANITIZER_LINUX 215uptr internal_mremap(void *old_address, uptr old_size, uptr new_size, int flags, 216 void *new_address) { 217 return internal_syscall(SYSCALL(mremap), (uptr)old_address, old_size, 218 new_size, flags, (uptr)new_address); 219} 220#endif 221 222int internal_mprotect(void *addr, uptr length, int prot) { 223 return internal_syscall(SYSCALL(mprotect), (uptr)addr, length, prot); 224} 225 226int internal_madvise(uptr addr, uptr length, int advice) { 227 return internal_syscall(SYSCALL(madvise), addr, length, advice); 228} 229 230uptr internal_close(fd_t fd) { 231 return internal_syscall(SYSCALL(close), fd); 232} 233 234uptr internal_open(const char *filename, int flags) { 235#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 236 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags); 237#else 238 return internal_syscall(SYSCALL(open), (uptr)filename, flags); 239#endif 240} 241 242uptr internal_open(const char *filename, int flags, u32 mode) { 243#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 244 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags, 245 mode); 246#else 247 return internal_syscall(SYSCALL(open), (uptr)filename, flags, mode); 248#endif 249} 250 251uptr internal_read(fd_t fd, void *buf, uptr count) { 252 sptr res; 253 HANDLE_EINTR(res, 254 (sptr)internal_syscall(SYSCALL(read), fd, (uptr)buf, count)); 255 return res; 256} 257 258uptr internal_write(fd_t fd, const void *buf, uptr count) { 259 sptr res; 260 HANDLE_EINTR(res, 261 (sptr)internal_syscall(SYSCALL(write), fd, (uptr)buf, count)); 262 return res; 263} 264 265uptr internal_ftruncate(fd_t fd, uptr size) { 266 sptr res; 267 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(ftruncate), fd, 268 (OFF_T)size)); 269 return res; 270} 271 272#if !SANITIZER_LINUX_USES_64BIT_SYSCALLS && SANITIZER_LINUX 273static void stat64_to_stat(struct stat64 *in, struct stat *out) { 274 internal_memset(out, 0, sizeof(*out)); 275 out->st_dev = in->st_dev; 276 out->st_ino = in->st_ino; 277 out->st_mode = in->st_mode; 278 out->st_nlink = in->st_nlink; 279 out->st_uid = in->st_uid; 280 out->st_gid = in->st_gid; 281 out->st_rdev = in->st_rdev; 282 out->st_size = in->st_size; 283 out->st_blksize = in->st_blksize; 284 out->st_blocks = in->st_blocks; 285 out->st_atime = in->st_atime; 286 out->st_mtime = in->st_mtime; 287 out->st_ctime = in->st_ctime; 288} 289#endif 290 291#if defined(__mips64) 292// Undefine compatibility macros from <sys/stat.h> 293// so that they would not clash with the kernel_stat 294// st_[a|m|c]time fields 295#if !SANITIZER_GO 296#undef st_atime 297#undef st_mtime 298#undef st_ctime 299#endif 300#if defined(SANITIZER_ANDROID) 301// Bionic sys/stat.h defines additional macros 302// for compatibility with the old NDKs and 303// they clash with the kernel_stat structure 304// st_[a|m|c]time_nsec fields. 305#undef st_atime_nsec 306#undef st_mtime_nsec 307#undef st_ctime_nsec 308#endif 309static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) { 310 internal_memset(out, 0, sizeof(*out)); 311 out->st_dev = in->st_dev; 312 out->st_ino = in->st_ino; 313 out->st_mode = in->st_mode; 314 out->st_nlink = in->st_nlink; 315 out->st_uid = in->st_uid; 316 out->st_gid = in->st_gid; 317 out->st_rdev = in->st_rdev; 318 out->st_size = in->st_size; 319 out->st_blksize = in->st_blksize; 320 out->st_blocks = in->st_blocks; 321#if defined(__USE_MISC) || \ 322 defined(__USE_XOPEN2K8) || \ 323 defined(SANITIZER_ANDROID) 324 out->st_atim.tv_sec = in->st_atime; 325 out->st_atim.tv_nsec = in->st_atime_nsec; 326 out->st_mtim.tv_sec = in->st_mtime; 327 out->st_mtim.tv_nsec = in->st_mtime_nsec; 328 out->st_ctim.tv_sec = in->st_ctime; 329 out->st_ctim.tv_nsec = in->st_ctime_nsec; 330#else 331 out->st_atime = in->st_atime; 332 out->st_atimensec = in->st_atime_nsec; 333 out->st_mtime = in->st_mtime; 334 out->st_mtimensec = in->st_mtime_nsec; 335 out->st_ctime = in->st_ctime; 336 out->st_atimensec = in->st_ctime_nsec; 337#endif 338} 339#endif 340 341uptr internal_stat(const char *path, void *buf) { 342#if SANITIZER_FREEBSD 343 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 0); 344#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 345 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 346 0); 347#elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 348# if defined(__mips64) 349 // For mips64, stat syscall fills buffer in the format of kernel_stat 350 struct kernel_stat kbuf; 351 int res = internal_syscall(SYSCALL(stat), path, &kbuf); 352 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 353 return res; 354# else 355 return internal_syscall(SYSCALL(stat), (uptr)path, (uptr)buf); 356# endif 357#else 358 struct stat64 buf64; 359 int res = internal_syscall(SYSCALL(stat64), path, &buf64); 360 stat64_to_stat(&buf64, (struct stat *)buf); 361 return res; 362#endif 363} 364 365uptr internal_lstat(const char *path, void *buf) { 366#if SANITIZER_FREEBSD 367 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 368 AT_SYMLINK_NOFOLLOW); 369#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 370 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf, 371 AT_SYMLINK_NOFOLLOW); 372#elif SANITIZER_LINUX_USES_64BIT_SYSCALLS 373# if SANITIZER_MIPS64 374 // For mips64, lstat syscall fills buffer in the format of kernel_stat 375 struct kernel_stat kbuf; 376 int res = internal_syscall(SYSCALL(lstat), path, &kbuf); 377 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 378 return res; 379# else 380 return internal_syscall(SYSCALL(lstat), (uptr)path, (uptr)buf); 381# endif 382#else 383 struct stat64 buf64; 384 int res = internal_syscall(SYSCALL(lstat64), path, &buf64); 385 stat64_to_stat(&buf64, (struct stat *)buf); 386 return res; 387#endif 388} 389 390uptr internal_fstat(fd_t fd, void *buf) { 391#if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS 392#if SANITIZER_MIPS64 393 // For mips64, fstat syscall fills buffer in the format of kernel_stat 394 struct kernel_stat kbuf; 395 int res = internal_syscall(SYSCALL(fstat), fd, &kbuf); 396 kernel_stat_to_stat(&kbuf, (struct stat *)buf); 397 return res; 398# else 399 return internal_syscall(SYSCALL(fstat), fd, (uptr)buf); 400# endif 401#else 402 struct stat64 buf64; 403 int res = internal_syscall(SYSCALL(fstat64), fd, &buf64); 404 stat64_to_stat(&buf64, (struct stat *)buf); 405 return res; 406#endif 407} 408 409uptr internal_filesize(fd_t fd) { 410 struct stat st; 411 if (internal_fstat(fd, &st)) 412 return -1; 413 return (uptr)st.st_size; 414} 415 416uptr internal_dup(int oldfd) { 417 return internal_syscall(SYSCALL(dup), oldfd); 418} 419 420uptr internal_dup2(int oldfd, int newfd) { 421#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 422 return internal_syscall(SYSCALL(dup3), oldfd, newfd, 0); 423#else 424 return internal_syscall(SYSCALL(dup2), oldfd, newfd); 425#endif 426} 427 428uptr internal_readlink(const char *path, char *buf, uptr bufsize) { 429#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 430 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD, (uptr)path, (uptr)buf, 431 bufsize); 432#else 433 return internal_syscall(SYSCALL(readlink), (uptr)path, (uptr)buf, bufsize); 434#endif 435} 436 437uptr internal_unlink(const char *path) { 438#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 439 return internal_syscall(SYSCALL(unlinkat), AT_FDCWD, (uptr)path, 0); 440#else 441 return internal_syscall(SYSCALL(unlink), (uptr)path); 442#endif 443} 444 445uptr internal_rename(const char *oldpath, const char *newpath) { 446#if defined(__riscv) && defined(__linux__) 447 return internal_syscall(SYSCALL(renameat2), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 448 (uptr)newpath, 0); 449#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 450 return internal_syscall(SYSCALL(renameat), AT_FDCWD, (uptr)oldpath, AT_FDCWD, 451 (uptr)newpath); 452#else 453 return internal_syscall(SYSCALL(rename), (uptr)oldpath, (uptr)newpath); 454#endif 455} 456 457uptr internal_sched_yield() { 458 return internal_syscall(SYSCALL(sched_yield)); 459} 460 461void internal_usleep(u64 useconds) { 462 struct timespec ts; 463 ts.tv_sec = useconds / 1000000; 464 ts.tv_nsec = (useconds % 1000000) * 1000; 465 internal_syscall(SYSCALL(nanosleep), &ts, &ts); 466} 467 468uptr internal_execve(const char *filename, char *const argv[], 469 char *const envp[]) { 470 return internal_syscall(SYSCALL(execve), (uptr)filename, (uptr)argv, 471 (uptr)envp); 472} 473#endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD 474 475#if !SANITIZER_NETBSD 476void internal__exit(int exitcode) { 477#if SANITIZER_FREEBSD || SANITIZER_SOLARIS 478 internal_syscall(SYSCALL(exit), exitcode); 479#else 480 internal_syscall(SYSCALL(exit_group), exitcode); 481#endif 482 Die(); // Unreachable. 483} 484#endif // !SANITIZER_NETBSD 485 486// ----------------- sanitizer_common.h 487bool FileExists(const char *filename) { 488 if (ShouldMockFailureToOpen(filename)) 489 return false; 490 struct stat st; 491#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 492 if (internal_syscall(SYSCALL(newfstatat), AT_FDCWD, filename, &st, 0)) 493#else 494 if (internal_stat(filename, &st)) 495#endif 496 return false; 497 // Sanity check: filename is a regular file. 498 return S_ISREG(st.st_mode); 499} 500 501#if !SANITIZER_NETBSD 502tid_t GetTid() { 503#if SANITIZER_FREEBSD 504 long Tid; 505 thr_self(&Tid); 506 return Tid; 507#elif SANITIZER_SOLARIS 508 return thr_self(); 509#else 510 return internal_syscall(SYSCALL(gettid)); 511#endif 512} 513 514int TgKill(pid_t pid, tid_t tid, int sig) { 515#if SANITIZER_LINUX 516 return internal_syscall(SYSCALL(tgkill), pid, tid, sig); 517#elif SANITIZER_FREEBSD 518 return internal_syscall(SYSCALL(thr_kill2), pid, tid, sig); 519#elif SANITIZER_SOLARIS 520 (void)pid; 521 return thr_kill(tid, sig); 522#endif 523} 524#endif 525 526#if SANITIZER_GLIBC 527u64 NanoTime() { 528 kernel_timeval tv; 529 internal_memset(&tv, 0, sizeof(tv)); 530 internal_syscall(SYSCALL(gettimeofday), &tv, 0); 531 return (u64)tv.tv_sec * 1000 * 1000 * 1000 + tv.tv_usec * 1000; 532} 533// Used by real_clock_gettime. 534uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) { 535 return internal_syscall(SYSCALL(clock_gettime), clk_id, tp); 536} 537#elif !SANITIZER_SOLARIS && !SANITIZER_NETBSD 538u64 NanoTime() { 539 struct timespec ts; 540 clock_gettime(CLOCK_REALTIME, &ts); 541 return (u64)ts.tv_sec * 1000 * 1000 * 1000 + ts.tv_nsec; 542} 543#endif 544 545// Like getenv, but reads env directly from /proc (on Linux) or parses the 546// 'environ' array (on some others) and does not use libc. This function 547// should be called first inside __asan_init. 548const char *GetEnv(const char *name) { 549#if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_SOLARIS 550 if (::environ != 0) { 551 uptr NameLen = internal_strlen(name); 552 for (char **Env = ::environ; *Env != 0; Env++) { 553 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=') 554 return (*Env) + NameLen + 1; 555 } 556 } 557 return 0; // Not found. 558#elif SANITIZER_LINUX 559 static char *environ; 560 static uptr len; 561 static bool inited; 562 if (!inited) { 563 inited = true; 564 uptr environ_size; 565 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len)) 566 environ = nullptr; 567 } 568 if (!environ || len == 0) return nullptr; 569 uptr namelen = internal_strlen(name); 570 const char *p = environ; 571 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer 572 // proc file has the format NAME=value\0NAME=value\0NAME=value\0... 573 const char* endp = 574 (char*)internal_memchr(p, '\0', len - (p - environ)); 575 if (!endp) // this entry isn't NUL terminated 576 return nullptr; 577 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match. 578 return p + namelen + 1; // point after = 579 p = endp + 1; 580 } 581 return nullptr; // Not found. 582#else 583#error "Unsupported platform" 584#endif 585} 586 587#if !SANITIZER_FREEBSD && !SANITIZER_NETBSD && !SANITIZER_GO 588extern "C" { 589SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end; 590} 591#endif 592 593#if !SANITIZER_FREEBSD && !SANITIZER_NETBSD 594static void ReadNullSepFileToArray(const char *path, char ***arr, 595 int arr_size) { 596 char *buff; 597 uptr buff_size; 598 uptr buff_len; 599 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray"); 600 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) { 601 (*arr)[0] = nullptr; 602 return; 603 } 604 (*arr)[0] = buff; 605 int count, i; 606 for (count = 1, i = 1; ; i++) { 607 if (buff[i] == 0) { 608 if (buff[i+1] == 0) break; 609 (*arr)[count] = &buff[i+1]; 610 CHECK_LE(count, arr_size - 1); // FIXME: make this more flexible. 611 count++; 612 } 613 } 614 (*arr)[count] = nullptr; 615} 616#endif 617 618static void GetArgsAndEnv(char ***argv, char ***envp) { 619#if SANITIZER_FREEBSD 620 // On FreeBSD, retrieving the argument and environment arrays is done via the 621 // kern.ps_strings sysctl, which returns a pointer to a structure containing 622 // this information. See also <sys/exec.h>. 623 ps_strings *pss; 624 uptr sz = sizeof(pss); 625 if (internal_sysctlbyname("kern.ps_strings", &pss, &sz, NULL, 0) == -1) { 626 Printf("sysctl kern.ps_strings failed\n"); 627 Die(); 628 } 629 *argv = pss->ps_argvstr; 630 *envp = pss->ps_envstr; 631#elif SANITIZER_NETBSD 632 *argv = __ps_strings->ps_argvstr; 633 *envp = __ps_strings->ps_envstr; 634#else // SANITIZER_FREEBSD 635#if !SANITIZER_GO 636 if (&__libc_stack_end) { 637 uptr* stack_end = (uptr*)__libc_stack_end; 638 // Normally argc can be obtained from *stack_end, however, on ARM glibc's 639 // _start clobbers it: 640 // https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/arm/start.S;hb=refs/heads/release/2.31/master#l75 641 // Do not special-case ARM and infer argc from argv everywhere. 642 int argc = 0; 643 while (stack_end[argc + 1]) argc++; 644 *argv = (char**)(stack_end + 1); 645 *envp = (char**)(stack_end + argc + 2); 646 } else { 647#endif // !SANITIZER_GO 648 static const int kMaxArgv = 2000, kMaxEnvp = 2000; 649 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv); 650 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp); 651#if !SANITIZER_GO 652 } 653#endif // !SANITIZER_GO 654#endif // SANITIZER_FREEBSD 655} 656 657char **GetArgv() { 658 char **argv, **envp; 659 GetArgsAndEnv(&argv, &envp); 660 return argv; 661} 662 663char **GetEnviron() { 664 char **argv, **envp; 665 GetArgsAndEnv(&argv, &envp); 666 return envp; 667} 668 669#if !SANITIZER_SOLARIS 670void FutexWait(atomic_uint32_t *p, u32 cmp) { 671# if SANITIZER_FREEBSD 672 _umtx_op(p, UMTX_OP_WAIT_UINT, cmp, 0, 0); 673# elif SANITIZER_NETBSD 674 sched_yield(); /* No userspace futex-like synchronization */ 675# else 676 internal_syscall(SYSCALL(futex), (uptr)p, FUTEX_WAIT_PRIVATE, cmp, 0, 0, 0); 677# endif 678} 679 680void FutexWake(atomic_uint32_t *p, u32 count) { 681# if SANITIZER_FREEBSD 682 _umtx_op(p, UMTX_OP_WAKE, count, 0, 0); 683# elif SANITIZER_NETBSD 684 /* No userspace futex-like synchronization */ 685# else 686 internal_syscall(SYSCALL(futex), (uptr)p, FUTEX_WAKE_PRIVATE, count, 0, 0, 0); 687# endif 688} 689 690# endif // !SANITIZER_SOLARIS 691 692// ----------------- sanitizer_linux.h 693// The actual size of this structure is specified by d_reclen. 694// Note that getdents64 uses a different structure format. We only provide the 695// 32-bit syscall here. 696#if SANITIZER_NETBSD 697// Not used 698#else 699struct linux_dirent { 700#if SANITIZER_X32 || defined(__aarch64__) || SANITIZER_RISCV64 701 u64 d_ino; 702 u64 d_off; 703#else 704 unsigned long d_ino; 705 unsigned long d_off; 706#endif 707 unsigned short d_reclen; 708#if defined(__aarch64__) || SANITIZER_RISCV64 709 unsigned char d_type; 710#endif 711 char d_name[256]; 712}; 713#endif 714 715#if !SANITIZER_SOLARIS && !SANITIZER_NETBSD 716// Syscall wrappers. 717uptr internal_ptrace(int request, int pid, void *addr, void *data) { 718 return internal_syscall(SYSCALL(ptrace), request, pid, (uptr)addr, 719 (uptr)data); 720} 721 722uptr internal_waitpid(int pid, int *status, int options) { 723 return internal_syscall(SYSCALL(wait4), pid, (uptr)status, options, 724 0 /* rusage */); 725} 726 727uptr internal_getpid() { 728 return internal_syscall(SYSCALL(getpid)); 729} 730 731uptr internal_getppid() { 732 return internal_syscall(SYSCALL(getppid)); 733} 734 735int internal_dlinfo(void *handle, int request, void *p) { 736#if SANITIZER_FREEBSD 737 return dlinfo(handle, request, p); 738#else 739 UNIMPLEMENTED(); 740#endif 741} 742 743uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) { 744#if SANITIZER_FREEBSD 745 return internal_syscall(SYSCALL(getdirentries), fd, (uptr)dirp, count, NULL); 746#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 747 return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count); 748#else 749 return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count); 750#endif 751} 752 753uptr internal_lseek(fd_t fd, OFF_T offset, int whence) { 754 return internal_syscall(SYSCALL(lseek), fd, offset, whence); 755} 756 757#if SANITIZER_LINUX 758uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) { 759 return internal_syscall(SYSCALL(prctl), option, arg2, arg3, arg4, arg5); 760} 761#endif 762 763uptr internal_sigaltstack(const void *ss, void *oss) { 764 return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss); 765} 766 767int internal_fork() { 768#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS 769 return internal_syscall(SYSCALL(clone), SIGCHLD, 0); 770#else 771 return internal_syscall(SYSCALL(fork)); 772#endif 773} 774 775#if SANITIZER_FREEBSD 776int internal_sysctl(const int *name, unsigned int namelen, void *oldp, 777 uptr *oldlenp, const void *newp, uptr newlen) { 778 return internal_syscall(SYSCALL(__sysctl), name, namelen, oldp, 779 (size_t *)oldlenp, newp, (size_t)newlen); 780} 781 782int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp, 783 const void *newp, uptr newlen) { 784 // Note: this function can be called during startup, so we need to avoid 785 // calling any interceptable functions. On FreeBSD >= 1300045 sysctlbyname() 786 // is a real syscall, but for older versions it calls sysctlnametomib() 787 // followed by sysctl(). To avoid calling the intercepted version and 788 // asserting if this happens during startup, call the real sysctlnametomib() 789 // followed by internal_sysctl() if the syscall is not available. 790#ifdef SYS___sysctlbyname 791 return internal_syscall(SYSCALL(__sysctlbyname), sname, 792 internal_strlen(sname), oldp, (size_t *)oldlenp, newp, 793 (size_t)newlen); 794#else 795 static decltype(sysctlnametomib) *real_sysctlnametomib = nullptr; 796 if (!real_sysctlnametomib) 797 real_sysctlnametomib = 798 (decltype(sysctlnametomib) *)dlsym(RTLD_NEXT, "sysctlnametomib"); 799 CHECK(real_sysctlnametomib); 800 801 int oid[CTL_MAXNAME]; 802 size_t len = CTL_MAXNAME; 803 if (real_sysctlnametomib(sname, oid, &len) == -1) 804 return (-1); 805 return internal_sysctl(oid, len, oldp, oldlenp, newp, newlen); 806#endif 807} 808#endif 809 810#if SANITIZER_LINUX 811#define SA_RESTORER 0x04000000 812// Doesn't set sa_restorer if the caller did not set it, so use with caution 813//(see below). 814int internal_sigaction_norestorer(int signum, const void *act, void *oldact) { 815 __sanitizer_kernel_sigaction_t k_act, k_oldact; 816 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t)); 817 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t)); 818 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act; 819 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact; 820 if (u_act) { 821 k_act.handler = u_act->handler; 822 k_act.sigaction = u_act->sigaction; 823 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask, 824 sizeof(__sanitizer_kernel_sigset_t)); 825 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL). 826 k_act.sa_flags = u_act->sa_flags | SA_RESTORER; 827 // FIXME: most often sa_restorer is unset, however the kernel requires it 828 // to point to a valid signal restorer that calls the rt_sigreturn syscall. 829 // If sa_restorer passed to the kernel is NULL, the program may crash upon 830 // signal delivery or fail to unwind the stack in the signal handler. 831 // libc implementation of sigaction() passes its own restorer to 832 // rt_sigaction, so we need to do the same (we'll need to reimplement the 833 // restorers; for x86_64 the restorer address can be obtained from 834 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact). 835#if !SANITIZER_ANDROID || !SANITIZER_MIPS32 836 k_act.sa_restorer = u_act->sa_restorer; 837#endif 838 } 839 840 uptr result = internal_syscall(SYSCALL(rt_sigaction), (uptr)signum, 841 (uptr)(u_act ? &k_act : nullptr), 842 (uptr)(u_oldact ? &k_oldact : nullptr), 843 (uptr)sizeof(__sanitizer_kernel_sigset_t)); 844 845 if ((result == 0) && u_oldact) { 846 u_oldact->handler = k_oldact.handler; 847 u_oldact->sigaction = k_oldact.sigaction; 848 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask, 849 sizeof(__sanitizer_kernel_sigset_t)); 850 u_oldact->sa_flags = k_oldact.sa_flags; 851#if !SANITIZER_ANDROID || !SANITIZER_MIPS32 852 u_oldact->sa_restorer = k_oldact.sa_restorer; 853#endif 854 } 855 return result; 856} 857#endif // SANITIZER_LINUX 858 859uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set, 860 __sanitizer_sigset_t *oldset) { 861#if SANITIZER_FREEBSD 862 return internal_syscall(SYSCALL(sigprocmask), how, set, oldset); 863#else 864 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 865 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset; 866 return internal_syscall(SYSCALL(rt_sigprocmask), (uptr)how, (uptr)k_set, 867 (uptr)k_oldset, sizeof(__sanitizer_kernel_sigset_t)); 868#endif 869} 870 871void internal_sigfillset(__sanitizer_sigset_t *set) { 872 internal_memset(set, 0xff, sizeof(*set)); 873} 874 875void internal_sigemptyset(__sanitizer_sigset_t *set) { 876 internal_memset(set, 0, sizeof(*set)); 877} 878 879#if SANITIZER_LINUX 880void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 881 signum -= 1; 882 CHECK_GE(signum, 0); 883 CHECK_LT(signum, sizeof(*set) * 8); 884 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 885 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 886 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 887 k_set->sig[idx] &= ~((uptr)1 << bit); 888} 889 890bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 891 signum -= 1; 892 CHECK_GE(signum, 0); 893 CHECK_LT(signum, sizeof(*set) * 8); 894 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set; 895 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8); 896 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8); 897 return k_set->sig[idx] & ((uptr)1 << bit); 898} 899#elif SANITIZER_FREEBSD 900void internal_sigdelset(__sanitizer_sigset_t *set, int signum) { 901 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 902 sigdelset(rset, signum); 903} 904 905bool internal_sigismember(__sanitizer_sigset_t *set, int signum) { 906 sigset_t *rset = reinterpret_cast<sigset_t *>(set); 907 return sigismember(rset, signum); 908} 909#endif 910#endif // !SANITIZER_SOLARIS 911 912#if !SANITIZER_NETBSD 913// ThreadLister implementation. 914ThreadLister::ThreadLister(pid_t pid) : pid_(pid), buffer_(4096) { 915 char task_directory_path[80]; 916 internal_snprintf(task_directory_path, sizeof(task_directory_path), 917 "/proc/%d/task/", pid); 918 descriptor_ = internal_open(task_directory_path, O_RDONLY | O_DIRECTORY); 919 if (internal_iserror(descriptor_)) { 920 Report("Can't open /proc/%d/task for reading.\n", pid); 921 } 922} 923 924ThreadLister::Result ThreadLister::ListThreads( 925 InternalMmapVector<tid_t> *threads) { 926 if (internal_iserror(descriptor_)) 927 return Error; 928 internal_lseek(descriptor_, 0, SEEK_SET); 929 threads->clear(); 930 931 Result result = Ok; 932 for (bool first_read = true;; first_read = false) { 933 // Resize to max capacity if it was downsized by IsAlive. 934 buffer_.resize(buffer_.capacity()); 935 CHECK_GE(buffer_.size(), 4096); 936 uptr read = internal_getdents( 937 descriptor_, (struct linux_dirent *)buffer_.data(), buffer_.size()); 938 if (!read) 939 return result; 940 if (internal_iserror(read)) { 941 Report("Can't read directory entries from /proc/%d/task.\n", pid_); 942 return Error; 943 } 944 945 for (uptr begin = (uptr)buffer_.data(), end = begin + read; begin < end;) { 946 struct linux_dirent *entry = (struct linux_dirent *)begin; 947 begin += entry->d_reclen; 948 if (entry->d_ino == 1) { 949 // Inode 1 is for bad blocks and also can be a reason for early return. 950 // Should be emitted if kernel tried to output terminating thread. 951 // See proc_task_readdir implementation in Linux. 952 result = Incomplete; 953 } 954 if (entry->d_ino && *entry->d_name >= '0' && *entry->d_name <= '9') 955 threads->push_back(internal_atoll(entry->d_name)); 956 } 957 958 // Now we are going to detect short-read or early EOF. In such cases Linux 959 // can return inconsistent list with missing alive threads. 960 // Code will just remember that the list can be incomplete but it will 961 // continue reads to return as much as possible. 962 if (!first_read) { 963 // The first one was a short-read by definition. 964 result = Incomplete; 965 } else if (read > buffer_.size() - 1024) { 966 // Read was close to the buffer size. So double the size and assume the 967 // worst. 968 buffer_.resize(buffer_.size() * 2); 969 result = Incomplete; 970 } else if (!threads->empty() && !IsAlive(threads->back())) { 971 // Maybe Linux early returned from read on terminated thread (!pid_alive) 972 // and failed to restore read position. 973 // See next_tid and proc_task_instantiate in Linux. 974 result = Incomplete; 975 } 976 } 977} 978 979bool ThreadLister::IsAlive(int tid) { 980 // /proc/%d/task/%d/status uses same call to detect alive threads as 981 // proc_task_readdir. See task_state implementation in Linux. 982 char path[80]; 983 internal_snprintf(path, sizeof(path), "/proc/%d/task/%d/status", pid_, tid); 984 if (!ReadFileToVector(path, &buffer_) || buffer_.empty()) 985 return false; 986 buffer_.push_back(0); 987 static const char kPrefix[] = "\nPPid:"; 988 const char *field = internal_strstr(buffer_.data(), kPrefix); 989 if (!field) 990 return false; 991 field += internal_strlen(kPrefix); 992 return (int)internal_atoll(field) != 0; 993} 994 995ThreadLister::~ThreadLister() { 996 if (!internal_iserror(descriptor_)) 997 internal_close(descriptor_); 998} 999#endif 1000 1001#if SANITIZER_WORDSIZE == 32 1002// Take care of unusable kernel area in top gigabyte. 1003static uptr GetKernelAreaSize() { 1004#if SANITIZER_LINUX && !SANITIZER_X32 1005 const uptr gbyte = 1UL << 30; 1006 1007 // Firstly check if there are writable segments 1008 // mapped to top gigabyte (e.g. stack). 1009 MemoryMappingLayout proc_maps(/*cache_enabled*/true); 1010 if (proc_maps.Error()) 1011 return 0; 1012 MemoryMappedSegment segment; 1013 while (proc_maps.Next(&segment)) { 1014 if ((segment.end >= 3 * gbyte) && segment.IsWritable()) return 0; 1015 } 1016 1017#if !SANITIZER_ANDROID 1018 // Even if nothing is mapped, top Gb may still be accessible 1019 // if we are running on 64-bit kernel. 1020 // Uname may report misleading results if personality type 1021 // is modified (e.g. under schroot) so check this as well. 1022 struct utsname uname_info; 1023 int pers = personality(0xffffffffUL); 1024 if (!(pers & PER_MASK) && internal_uname(&uname_info) == 0 && 1025 internal_strstr(uname_info.machine, "64")) 1026 return 0; 1027#endif // SANITIZER_ANDROID 1028 1029 // Top gigabyte is reserved for kernel. 1030 return gbyte; 1031#else 1032 return 0; 1033#endif // SANITIZER_LINUX && !SANITIZER_X32 1034} 1035#endif // SANITIZER_WORDSIZE == 32 1036 1037uptr GetMaxVirtualAddress() { 1038#if SANITIZER_NETBSD && defined(__x86_64__) 1039 return 0x7f7ffffff000ULL; // (0x00007f8000000000 - PAGE_SIZE) 1040#elif SANITIZER_WORDSIZE == 64 1041# if defined(__powerpc64__) || defined(__aarch64__) 1042 // On PowerPC64 we have two different address space layouts: 44- and 46-bit. 1043 // We somehow need to figure out which one we are using now and choose 1044 // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL. 1045 // Note that with 'ulimit -s unlimited' the stack is moved away from the top 1046 // of the address space, so simply checking the stack address is not enough. 1047 // This should (does) work for both PowerPC64 Endian modes. 1048 // Similarly, aarch64 has multiple address space layouts: 39, 42 and 47-bit. 1049 return (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1)) - 1; 1050#elif SANITIZER_RISCV64 1051 return (1ULL << 38) - 1; 1052# elif defined(__mips64) 1053 return (1ULL << 40) - 1; // 0x000000ffffffffffUL; 1054# elif defined(__s390x__) 1055 return (1ULL << 53) - 1; // 0x001fffffffffffffUL; 1056#elif defined(__sparc__) 1057 return ~(uptr)0; 1058# else 1059 return (1ULL << 47) - 1; // 0x00007fffffffffffUL; 1060# endif 1061#else // SANITIZER_WORDSIZE == 32 1062# if defined(__s390__) 1063 return (1ULL << 31) - 1; // 0x7fffffff; 1064# else 1065 return (1ULL << 32) - 1; // 0xffffffff; 1066# endif 1067#endif // SANITIZER_WORDSIZE 1068} 1069 1070uptr GetMaxUserVirtualAddress() { 1071 uptr addr = GetMaxVirtualAddress(); 1072#if SANITIZER_WORDSIZE == 32 && !defined(__s390__) 1073 if (!common_flags()->full_address_space) 1074 addr -= GetKernelAreaSize(); 1075 CHECK_LT(reinterpret_cast<uptr>(&addr), addr); 1076#endif 1077 return addr; 1078} 1079 1080#if !SANITIZER_ANDROID 1081uptr GetPageSize() { 1082#if SANITIZER_LINUX && (defined(__x86_64__) || defined(__i386__)) && \ 1083 defined(EXEC_PAGESIZE) 1084 return EXEC_PAGESIZE; 1085#elif SANITIZER_FREEBSD || SANITIZER_NETBSD 1086// Use sysctl as sysconf can trigger interceptors internally. 1087 int pz = 0; 1088 uptr pzl = sizeof(pz); 1089 int mib[2] = {CTL_HW, HW_PAGESIZE}; 1090 int rv = internal_sysctl(mib, 2, &pz, &pzl, nullptr, 0); 1091 CHECK_EQ(rv, 0); 1092 return (uptr)pz; 1093#elif SANITIZER_USE_GETAUXVAL 1094 return getauxval(AT_PAGESZ); 1095#else 1096 return sysconf(_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy. 1097#endif 1098} 1099#endif // !SANITIZER_ANDROID 1100 1101uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) { 1102#if SANITIZER_SOLARIS 1103 const char *default_module_name = getexecname(); 1104 CHECK_NE(default_module_name, NULL); 1105 return internal_snprintf(buf, buf_len, "%s", default_module_name); 1106#else 1107#if SANITIZER_FREEBSD || SANITIZER_NETBSD 1108#if SANITIZER_FREEBSD 1109 const int Mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1}; 1110#else 1111 const int Mib[4] = {CTL_KERN, KERN_PROC_ARGS, -1, KERN_PROC_PATHNAME}; 1112#endif 1113 const char *default_module_name = "kern.proc.pathname"; 1114 uptr Size = buf_len; 1115 bool IsErr = 1116 (internal_sysctl(Mib, ARRAY_SIZE(Mib), buf, &Size, NULL, 0) != 0); 1117 int readlink_error = IsErr ? errno : 0; 1118 uptr module_name_len = Size; 1119#else 1120 const char *default_module_name = "/proc/self/exe"; 1121 uptr module_name_len = internal_readlink( 1122 default_module_name, buf, buf_len); 1123 int readlink_error; 1124 bool IsErr = internal_iserror(module_name_len, &readlink_error); 1125#endif // SANITIZER_SOLARIS 1126 if (IsErr) { 1127 // We can't read binary name for some reason, assume it's unknown. 1128 Report("WARNING: reading executable name failed with errno %d, " 1129 "some stack frames may not be symbolized\n", readlink_error); 1130 module_name_len = internal_snprintf(buf, buf_len, "%s", 1131 default_module_name); 1132 CHECK_LT(module_name_len, buf_len); 1133 } 1134 return module_name_len; 1135#endif 1136} 1137 1138uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) { 1139#if SANITIZER_LINUX 1140 char *tmpbuf; 1141 uptr tmpsize; 1142 uptr tmplen; 1143 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen, 1144 1024 * 1024)) { 1145 internal_strncpy(buf, tmpbuf, buf_len); 1146 UnmapOrDie(tmpbuf, tmpsize); 1147 return internal_strlen(buf); 1148 } 1149#endif 1150 return ReadBinaryName(buf, buf_len); 1151} 1152 1153// Match full names of the form /path/to/base_name{-,.}* 1154bool LibraryNameIs(const char *full_name, const char *base_name) { 1155 const char *name = full_name; 1156 // Strip path. 1157 while (*name != '\0') name++; 1158 while (name > full_name && *name != '/') name--; 1159 if (*name == '/') name++; 1160 uptr base_name_length = internal_strlen(base_name); 1161 if (internal_strncmp(name, base_name, base_name_length)) return false; 1162 return (name[base_name_length] == '-' || name[base_name_length] == '.'); 1163} 1164 1165#if !SANITIZER_ANDROID 1166// Call cb for each region mapped by map. 1167void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) { 1168 CHECK_NE(map, nullptr); 1169#if !SANITIZER_FREEBSD 1170 typedef ElfW(Phdr) Elf_Phdr; 1171 typedef ElfW(Ehdr) Elf_Ehdr; 1172#endif // !SANITIZER_FREEBSD 1173 char *base = (char *)map->l_addr; 1174 Elf_Ehdr *ehdr = (Elf_Ehdr *)base; 1175 char *phdrs = base + ehdr->e_phoff; 1176 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize; 1177 1178 // Find the segment with the minimum base so we can "relocate" the p_vaddr 1179 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC 1180 // objects have a non-zero base. 1181 uptr preferred_base = (uptr)-1; 1182 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1183 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1184 if (phdr->p_type == PT_LOAD && preferred_base > (uptr)phdr->p_vaddr) 1185 preferred_base = (uptr)phdr->p_vaddr; 1186 } 1187 1188 // Compute the delta from the real base to get a relocation delta. 1189 sptr delta = (uptr)base - preferred_base; 1190 // Now we can figure out what the loader really mapped. 1191 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) { 1192 Elf_Phdr *phdr = (Elf_Phdr *)iter; 1193 if (phdr->p_type == PT_LOAD) { 1194 uptr seg_start = phdr->p_vaddr + delta; 1195 uptr seg_end = seg_start + phdr->p_memsz; 1196 // None of these values are aligned. We consider the ragged edges of the 1197 // load command as defined, since they are mapped from the file. 1198 seg_start = RoundDownTo(seg_start, GetPageSizeCached()); 1199 seg_end = RoundUpTo(seg_end, GetPageSizeCached()); 1200 cb((void *)seg_start, seg_end - seg_start); 1201 } 1202 } 1203} 1204#endif 1205 1206#if SANITIZER_LINUX 1207#if defined(__x86_64__) 1208// We cannot use glibc's clone wrapper, because it messes with the child 1209// task's TLS. It writes the PID and TID of the child task to its thread 1210// descriptor, but in our case the child task shares the thread descriptor with 1211// the parent (because we don't know how to allocate a new thread 1212// descriptor to keep glibc happy). So the stock version of clone(), when 1213// used with CLONE_VM, would end up corrupting the parent's thread descriptor. 1214uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1215 int *parent_tidptr, void *newtls, int *child_tidptr) { 1216 long long res; 1217 if (!fn || !child_stack) 1218 return -EINVAL; 1219 CHECK_EQ(0, (uptr)child_stack % 16); 1220 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1221 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1222 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1223 register void *r8 __asm__("r8") = newtls; 1224 register int *r10 __asm__("r10") = child_tidptr; 1225 __asm__ __volatile__( 1226 /* %rax = syscall(%rax = SYSCALL(clone), 1227 * %rdi = flags, 1228 * %rsi = child_stack, 1229 * %rdx = parent_tidptr, 1230 * %r8 = new_tls, 1231 * %r10 = child_tidptr) 1232 */ 1233 "syscall\n" 1234 1235 /* if (%rax != 0) 1236 * return; 1237 */ 1238 "testq %%rax,%%rax\n" 1239 "jnz 1f\n" 1240 1241 /* In the child. Terminate unwind chain. */ 1242 // XXX: We should also terminate the CFI unwind chain 1243 // here. Unfortunately clang 3.2 doesn't support the 1244 // necessary CFI directives, so we skip that part. 1245 "xorq %%rbp,%%rbp\n" 1246 1247 /* Call "fn(arg)". */ 1248 "popq %%rax\n" 1249 "popq %%rdi\n" 1250 "call *%%rax\n" 1251 1252 /* Call _exit(%rax). */ 1253 "movq %%rax,%%rdi\n" 1254 "movq %2,%%rax\n" 1255 "syscall\n" 1256 1257 /* Return to parent. */ 1258 "1:\n" 1259 : "=a" (res) 1260 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1261 "S"(child_stack), 1262 "D"(flags), 1263 "d"(parent_tidptr), 1264 "r"(r8), 1265 "r"(r10) 1266 : "memory", "r11", "rcx"); 1267 return res; 1268} 1269#elif defined(__mips__) 1270uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1271 int *parent_tidptr, void *newtls, int *child_tidptr) { 1272 long long res; 1273 if (!fn || !child_stack) 1274 return -EINVAL; 1275 CHECK_EQ(0, (uptr)child_stack % 16); 1276 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1277 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1278 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1279 register void *a3 __asm__("$7") = newtls; 1280 register int *a4 __asm__("$8") = child_tidptr; 1281 // We don't have proper CFI directives here because it requires alot of code 1282 // for very marginal benefits. 1283 __asm__ __volatile__( 1284 /* $v0 = syscall($v0 = __NR_clone, 1285 * $a0 = flags, 1286 * $a1 = child_stack, 1287 * $a2 = parent_tidptr, 1288 * $a3 = new_tls, 1289 * $a4 = child_tidptr) 1290 */ 1291 ".cprestore 16;\n" 1292 "move $4,%1;\n" 1293 "move $5,%2;\n" 1294 "move $6,%3;\n" 1295 "move $7,%4;\n" 1296 /* Store the fifth argument on stack 1297 * if we are using 32-bit abi. 1298 */ 1299#if SANITIZER_WORDSIZE == 32 1300 "lw %5,16($29);\n" 1301#else 1302 "move $8,%5;\n" 1303#endif 1304 "li $2,%6;\n" 1305 "syscall;\n" 1306 1307 /* if ($v0 != 0) 1308 * return; 1309 */ 1310 "bnez $2,1f;\n" 1311 1312 /* Call "fn(arg)". */ 1313#if SANITIZER_WORDSIZE == 32 1314#ifdef __BIG_ENDIAN__ 1315 "lw $25,4($29);\n" 1316 "lw $4,12($29);\n" 1317#else 1318 "lw $25,0($29);\n" 1319 "lw $4,8($29);\n" 1320#endif 1321#else 1322 "ld $25,0($29);\n" 1323 "ld $4,8($29);\n" 1324#endif 1325 "jal $25;\n" 1326 1327 /* Call _exit($v0). */ 1328 "move $4,$2;\n" 1329 "li $2,%7;\n" 1330 "syscall;\n" 1331 1332 /* Return to parent. */ 1333 "1:\n" 1334 : "=r" (res) 1335 : "r"(flags), 1336 "r"(child_stack), 1337 "r"(parent_tidptr), 1338 "r"(a3), 1339 "r"(a4), 1340 "i"(__NR_clone), 1341 "i"(__NR_exit) 1342 : "memory", "$29" ); 1343 return res; 1344} 1345#elif SANITIZER_RISCV64 1346uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1347 int *parent_tidptr, void *newtls, int *child_tidptr) { 1348 if (!fn || !child_stack) 1349 return -EINVAL; 1350 1351 CHECK_EQ(0, (uptr)child_stack % 16); 1352 1353 register int res __asm__("a0"); 1354 register int __flags __asm__("a0") = flags; 1355 register void *__stack __asm__("a1") = child_stack; 1356 register int *__ptid __asm__("a2") = parent_tidptr; 1357 register void *__tls __asm__("a3") = newtls; 1358 register int *__ctid __asm__("a4") = child_tidptr; 1359 register int (*__fn)(void *) __asm__("a5") = fn; 1360 register void *__arg __asm__("a6") = arg; 1361 register int nr_clone __asm__("a7") = __NR_clone; 1362 1363 __asm__ __volatile__( 1364 "ecall\n" 1365 1366 /* if (a0 != 0) 1367 * return a0; 1368 */ 1369 "bnez a0, 1f\n" 1370 1371 // In the child, now. Call "fn(arg)". 1372 "mv a0, a6\n" 1373 "jalr a5\n" 1374 1375 // Call _exit(a0). 1376 "addi a7, zero, %9\n" 1377 "ecall\n" 1378 "1:\n" 1379 1380 : "=r"(res) 1381 : "0"(__flags), "r"(__stack), "r"(__ptid), "r"(__tls), "r"(__ctid), 1382 "r"(__fn), "r"(__arg), "r"(nr_clone), "i"(__NR_exit) 1383 : "memory"); 1384 return res; 1385} 1386#elif defined(__aarch64__) 1387uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1388 int *parent_tidptr, void *newtls, int *child_tidptr) { 1389 long long res; 1390 if (!fn || !child_stack) 1391 return -EINVAL; 1392 CHECK_EQ(0, (uptr)child_stack % 16); 1393 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long); 1394 ((unsigned long long *)child_stack)[0] = (uptr)fn; 1395 ((unsigned long long *)child_stack)[1] = (uptr)arg; 1396 1397 register int (*__fn)(void *) __asm__("x0") = fn; 1398 register void *__stack __asm__("x1") = child_stack; 1399 register int __flags __asm__("x2") = flags; 1400 register void *__arg __asm__("x3") = arg; 1401 register int *__ptid __asm__("x4") = parent_tidptr; 1402 register void *__tls __asm__("x5") = newtls; 1403 register int *__ctid __asm__("x6") = child_tidptr; 1404 1405 __asm__ __volatile__( 1406 "mov x0,x2\n" /* flags */ 1407 "mov x2,x4\n" /* ptid */ 1408 "mov x3,x5\n" /* tls */ 1409 "mov x4,x6\n" /* ctid */ 1410 "mov x8,%9\n" /* clone */ 1411 1412 "svc 0x0\n" 1413 1414 /* if (%r0 != 0) 1415 * return %r0; 1416 */ 1417 "cmp x0, #0\n" 1418 "bne 1f\n" 1419 1420 /* In the child, now. Call "fn(arg)". */ 1421 "ldp x1, x0, [sp], #16\n" 1422 "blr x1\n" 1423 1424 /* Call _exit(%r0). */ 1425 "mov x8, %10\n" 1426 "svc 0x0\n" 1427 "1:\n" 1428 1429 : "=r" (res) 1430 : "i"(-EINVAL), 1431 "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg), 1432 "r"(__ptid), "r"(__tls), "r"(__ctid), 1433 "i"(__NR_clone), "i"(__NR_exit) 1434 : "x30", "memory"); 1435 return res; 1436} 1437#elif defined(__powerpc64__) 1438uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1439 int *parent_tidptr, void *newtls, int *child_tidptr) { 1440 long long res; 1441// Stack frame structure. 1442#if SANITIZER_PPC64V1 1443// Back chain == 0 (SP + 112) 1444// Frame (112 bytes): 1445// Parameter save area (SP + 48), 8 doublewords 1446// TOC save area (SP + 40) 1447// Link editor doubleword (SP + 32) 1448// Compiler doubleword (SP + 24) 1449// LR save area (SP + 16) 1450// CR save area (SP + 8) 1451// Back chain (SP + 0) 1452# define FRAME_SIZE 112 1453# define FRAME_TOC_SAVE_OFFSET 40 1454#elif SANITIZER_PPC64V2 1455// Back chain == 0 (SP + 32) 1456// Frame (32 bytes): 1457// TOC save area (SP + 24) 1458// LR save area (SP + 16) 1459// CR save area (SP + 8) 1460// Back chain (SP + 0) 1461# define FRAME_SIZE 32 1462# define FRAME_TOC_SAVE_OFFSET 24 1463#else 1464# error "Unsupported PPC64 ABI" 1465#endif 1466 if (!fn || !child_stack) 1467 return -EINVAL; 1468 CHECK_EQ(0, (uptr)child_stack % 16); 1469 1470 register int (*__fn)(void *) __asm__("r3") = fn; 1471 register void *__cstack __asm__("r4") = child_stack; 1472 register int __flags __asm__("r5") = flags; 1473 register void *__arg __asm__("r6") = arg; 1474 register int *__ptidptr __asm__("r7") = parent_tidptr; 1475 register void *__newtls __asm__("r8") = newtls; 1476 register int *__ctidptr __asm__("r9") = child_tidptr; 1477 1478 __asm__ __volatile__( 1479 /* fn and arg are saved across the syscall */ 1480 "mr 28, %5\n\t" 1481 "mr 27, %8\n\t" 1482 1483 /* syscall 1484 r0 == __NR_clone 1485 r3 == flags 1486 r4 == child_stack 1487 r5 == parent_tidptr 1488 r6 == newtls 1489 r7 == child_tidptr */ 1490 "mr 3, %7\n\t" 1491 "mr 5, %9\n\t" 1492 "mr 6, %10\n\t" 1493 "mr 7, %11\n\t" 1494 "li 0, %3\n\t" 1495 "sc\n\t" 1496 1497 /* Test if syscall was successful */ 1498 "cmpdi cr1, 3, 0\n\t" 1499 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t" 1500 "bne- cr1, 1f\n\t" 1501 1502 /* Set up stack frame */ 1503 "li 29, 0\n\t" 1504 "stdu 29, -8(1)\n\t" 1505 "stdu 1, -%12(1)\n\t" 1506 /* Do the function call */ 1507 "std 2, %13(1)\n\t" 1508#if SANITIZER_PPC64V1 1509 "ld 0, 0(28)\n\t" 1510 "ld 2, 8(28)\n\t" 1511 "mtctr 0\n\t" 1512#elif SANITIZER_PPC64V2 1513 "mr 12, 28\n\t" 1514 "mtctr 12\n\t" 1515#else 1516# error "Unsupported PPC64 ABI" 1517#endif 1518 "mr 3, 27\n\t" 1519 "bctrl\n\t" 1520 "ld 2, %13(1)\n\t" 1521 1522 /* Call _exit(r3) */ 1523 "li 0, %4\n\t" 1524 "sc\n\t" 1525 1526 /* Return to parent */ 1527 "1:\n\t" 1528 "mr %0, 3\n\t" 1529 : "=r" (res) 1530 : "0" (-1), 1531 "i" (EINVAL), 1532 "i" (__NR_clone), 1533 "i" (__NR_exit), 1534 "r" (__fn), 1535 "r" (__cstack), 1536 "r" (__flags), 1537 "r" (__arg), 1538 "r" (__ptidptr), 1539 "r" (__newtls), 1540 "r" (__ctidptr), 1541 "i" (FRAME_SIZE), 1542 "i" (FRAME_TOC_SAVE_OFFSET) 1543 : "cr0", "cr1", "memory", "ctr", "r0", "r27", "r28", "r29"); 1544 return res; 1545} 1546#elif defined(__i386__) 1547uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1548 int *parent_tidptr, void *newtls, int *child_tidptr) { 1549 int res; 1550 if (!fn || !child_stack) 1551 return -EINVAL; 1552 CHECK_EQ(0, (uptr)child_stack % 16); 1553 child_stack = (char *)child_stack - 7 * sizeof(unsigned int); 1554 ((unsigned int *)child_stack)[0] = (uptr)flags; 1555 ((unsigned int *)child_stack)[1] = (uptr)0; 1556 ((unsigned int *)child_stack)[2] = (uptr)fn; 1557 ((unsigned int *)child_stack)[3] = (uptr)arg; 1558 __asm__ __volatile__( 1559 /* %eax = syscall(%eax = SYSCALL(clone), 1560 * %ebx = flags, 1561 * %ecx = child_stack, 1562 * %edx = parent_tidptr, 1563 * %esi = new_tls, 1564 * %edi = child_tidptr) 1565 */ 1566 1567 /* Obtain flags */ 1568 "movl (%%ecx), %%ebx\n" 1569 /* Do the system call */ 1570 "pushl %%ebx\n" 1571 "pushl %%esi\n" 1572 "pushl %%edi\n" 1573 /* Remember the flag value. */ 1574 "movl %%ebx, (%%ecx)\n" 1575 "int $0x80\n" 1576 "popl %%edi\n" 1577 "popl %%esi\n" 1578 "popl %%ebx\n" 1579 1580 /* if (%eax != 0) 1581 * return; 1582 */ 1583 1584 "test %%eax,%%eax\n" 1585 "jnz 1f\n" 1586 1587 /* terminate the stack frame */ 1588 "xorl %%ebp,%%ebp\n" 1589 /* Call FN. */ 1590 "call *%%ebx\n" 1591#ifdef PIC 1592 "call here\n" 1593 "here:\n" 1594 "popl %%ebx\n" 1595 "addl $_GLOBAL_OFFSET_TABLE_+[.-here], %%ebx\n" 1596#endif 1597 /* Call exit */ 1598 "movl %%eax, %%ebx\n" 1599 "movl %2, %%eax\n" 1600 "int $0x80\n" 1601 "1:\n" 1602 : "=a" (res) 1603 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), 1604 "c"(child_stack), 1605 "d"(parent_tidptr), 1606 "S"(newtls), 1607 "D"(child_tidptr) 1608 : "memory"); 1609 return res; 1610} 1611#elif defined(__arm__) 1612uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 1613 int *parent_tidptr, void *newtls, int *child_tidptr) { 1614 unsigned int res; 1615 if (!fn || !child_stack) 1616 return -EINVAL; 1617 child_stack = (char *)child_stack - 2 * sizeof(unsigned int); 1618 ((unsigned int *)child_stack)[0] = (uptr)fn; 1619 ((unsigned int *)child_stack)[1] = (uptr)arg; 1620 register int r0 __asm__("r0") = flags; 1621 register void *r1 __asm__("r1") = child_stack; 1622 register int *r2 __asm__("r2") = parent_tidptr; 1623 register void *r3 __asm__("r3") = newtls; 1624 register int *r4 __asm__("r4") = child_tidptr; 1625 register int r7 __asm__("r7") = __NR_clone; 1626 1627#if __ARM_ARCH > 4 || defined (__ARM_ARCH_4T__) 1628# define ARCH_HAS_BX 1629#endif 1630#if __ARM_ARCH > 4 1631# define ARCH_HAS_BLX 1632#endif 1633 1634#ifdef ARCH_HAS_BX 1635# ifdef ARCH_HAS_BLX 1636# define BLX(R) "blx " #R "\n" 1637# else 1638# define BLX(R) "mov lr, pc; bx " #R "\n" 1639# endif 1640#else 1641# define BLX(R) "mov lr, pc; mov pc," #R "\n" 1642#endif 1643 1644 __asm__ __volatile__( 1645 /* %r0 = syscall(%r7 = SYSCALL(clone), 1646 * %r0 = flags, 1647 * %r1 = child_stack, 1648 * %r2 = parent_tidptr, 1649 * %r3 = new_tls, 1650 * %r4 = child_tidptr) 1651 */ 1652 1653 /* Do the system call */ 1654 "swi 0x0\n" 1655 1656 /* if (%r0 != 0) 1657 * return %r0; 1658 */ 1659 "cmp r0, #0\n" 1660 "bne 1f\n" 1661 1662 /* In the child, now. Call "fn(arg)". */ 1663 "ldr r0, [sp, #4]\n" 1664 "ldr ip, [sp], #8\n" 1665 BLX(ip) 1666 /* Call _exit(%r0). */ 1667 "mov r7, %7\n" 1668 "swi 0x0\n" 1669 "1:\n" 1670 "mov %0, r0\n" 1671 : "=r"(res) 1672 : "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r7), 1673 "i"(__NR_exit) 1674 : "memory"); 1675 return res; 1676} 1677#endif 1678#endif // SANITIZER_LINUX 1679 1680#if SANITIZER_LINUX 1681int internal_uname(struct utsname *buf) { 1682 return internal_syscall(SYSCALL(uname), buf); 1683} 1684#endif 1685 1686#if SANITIZER_ANDROID 1687#if __ANDROID_API__ < 21 1688extern "C" __attribute__((weak)) int dl_iterate_phdr( 1689 int (*)(struct dl_phdr_info *, size_t, void *), void *); 1690#endif 1691 1692static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size, 1693 void *data) { 1694 // Any name starting with "lib" indicates a bug in L where library base names 1695 // are returned instead of paths. 1696 if (info->dlpi_name && info->dlpi_name[0] == 'l' && 1697 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') { 1698 *(bool *)data = true; 1699 return 1; 1700 } 1701 return 0; 1702} 1703 1704static atomic_uint32_t android_api_level; 1705 1706static AndroidApiLevel AndroidDetectApiLevelStatic() { 1707#if __ANDROID_API__ <= 19 1708 return ANDROID_KITKAT; 1709#elif __ANDROID_API__ <= 22 1710 return ANDROID_LOLLIPOP_MR1; 1711#else 1712 return ANDROID_POST_LOLLIPOP; 1713#endif 1714} 1715 1716static AndroidApiLevel AndroidDetectApiLevel() { 1717 if (!&dl_iterate_phdr) 1718 return ANDROID_KITKAT; // K or lower 1719 bool base_name_seen = false; 1720 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen); 1721 if (base_name_seen) 1722 return ANDROID_LOLLIPOP_MR1; // L MR1 1723 return ANDROID_POST_LOLLIPOP; // post-L 1724 // Plain L (API level 21) is completely broken wrt ASan and not very 1725 // interesting to detect. 1726} 1727 1728extern "C" __attribute__((weak)) void* _DYNAMIC; 1729 1730AndroidApiLevel AndroidGetApiLevel() { 1731 AndroidApiLevel level = 1732 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed); 1733 if (level) return level; 1734 level = &_DYNAMIC == nullptr ? AndroidDetectApiLevelStatic() 1735 : AndroidDetectApiLevel(); 1736 atomic_store(&android_api_level, level, memory_order_relaxed); 1737 return level; 1738} 1739 1740#endif 1741 1742static HandleSignalMode GetHandleSignalModeImpl(int signum) { 1743 switch (signum) { 1744 case SIGABRT: 1745 return common_flags()->handle_abort; 1746 case SIGILL: 1747 return common_flags()->handle_sigill; 1748 case SIGTRAP: 1749 return common_flags()->handle_sigtrap; 1750 case SIGFPE: 1751 return common_flags()->handle_sigfpe; 1752 case SIGSEGV: 1753 return common_flags()->handle_segv; 1754 case SIGBUS: 1755 return common_flags()->handle_sigbus; 1756 } 1757 return kHandleSignalNo; 1758} 1759 1760HandleSignalMode GetHandleSignalMode(int signum) { 1761 HandleSignalMode result = GetHandleSignalModeImpl(signum); 1762 if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler) 1763 return kHandleSignalExclusive; 1764 return result; 1765} 1766 1767#if !SANITIZER_GO 1768void *internal_start_thread(void *(*func)(void *arg), void *arg) { 1769 // Start the thread with signals blocked, otherwise it can steal user signals. 1770 ScopedBlockSignals block(nullptr); 1771 void *th; 1772 real_pthread_create(&th, nullptr, func, arg); 1773 return th; 1774} 1775 1776void internal_join_thread(void *th) { 1777 real_pthread_join(th, nullptr); 1778} 1779#else 1780void *internal_start_thread(void *(*func)(void *), void *arg) { return 0; } 1781 1782void internal_join_thread(void *th) {} 1783#endif 1784 1785#if defined(__aarch64__) 1786// Android headers in the older NDK releases miss this definition. 1787#if SANITIZER_LINUX 1788struct __sanitizer_esr_context { 1789 struct _aarch64_ctx head; 1790 uint64_t esr; 1791}; 1792#endif 1793 1794static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) { 1795#if SANITIZER_LINUX 1796 static const u32 kEsrMagic = 0x45535201; 1797 u8 *aux = reinterpret_cast<u8 *>(ucontext->uc_mcontext.__reserved); 1798 while (true) { 1799 _aarch64_ctx *ctx = (_aarch64_ctx *)aux; 1800 if (ctx->size == 0) break; 1801 if (ctx->magic == kEsrMagic) { 1802 *esr = ((__sanitizer_esr_context *)ctx)->esr; 1803 return true; 1804 } 1805 aux += ctx->size; 1806 } 1807#endif 1808 return false; 1809} 1810#endif 1811 1812using Context = ucontext_t; 1813 1814SignalContext::WriteFlag SignalContext::GetWriteFlag() const { 1815 Context *ucontext = (Context *)context; 1816#if defined(__x86_64__) || defined(__i386__) 1817 static const uptr PF_WRITE = 1U << 1; 1818#if SANITIZER_FREEBSD 1819 uptr err = ucontext->uc_mcontext.mc_err; 1820#elif SANITIZER_NETBSD 1821 uptr err = ucontext->uc_mcontext.__gregs[_REG_ERR]; 1822#elif SANITIZER_SOLARIS && defined(__i386__) 1823 const int Err = 13; 1824 uptr err = ucontext->uc_mcontext.gregs[Err]; 1825#else 1826 uptr err = ucontext->uc_mcontext.gregs[REG_ERR]; 1827#endif // SANITIZER_FREEBSD 1828 return err & PF_WRITE ? WRITE : READ; 1829#elif defined(__mips__) 1830 uint32_t *exception_source; 1831 uint32_t faulty_instruction; 1832 uint32_t op_code; 1833 1834#if SANITIZER_NETBSD 1835 ucontext_t *nucontext = (ucontext_t *)ucontext; 1836 exception_source = (uint32_t *)_UC_MACHINE_PC(nucontext); 1837#else 1838 exception_source = (uint32_t *)ucontext->uc_mcontext.pc; 1839#endif 1840 faulty_instruction = (uint32_t)(*exception_source); 1841 1842 op_code = (faulty_instruction >> 26) & 0x3f; 1843 1844 // FIXME: Add support for FPU, microMIPS, DSP, MSA memory instructions. 1845 switch (op_code) { 1846 case 0x28: // sb 1847 case 0x29: // sh 1848 case 0x2b: // sw 1849 case 0x3f: // sd 1850#if __mips_isa_rev < 6 1851 case 0x2c: // sdl 1852 case 0x2d: // sdr 1853 case 0x2a: // swl 1854 case 0x2e: // swr 1855#endif 1856 return SignalContext::WRITE; 1857 1858 case 0x20: // lb 1859 case 0x24: // lbu 1860 case 0x21: // lh 1861 case 0x25: // lhu 1862 case 0x23: // lw 1863 case 0x27: // lwu 1864 case 0x37: // ld 1865#if __mips_isa_rev < 6 1866 case 0x1a: // ldl 1867 case 0x1b: // ldr 1868 case 0x22: // lwl 1869 case 0x26: // lwr 1870#endif 1871 return SignalContext::READ; 1872#if __mips_isa_rev == 6 1873 case 0x3b: // pcrel 1874 op_code = (faulty_instruction >> 19) & 0x3; 1875 switch (op_code) { 1876 case 0x1: // lwpc 1877 case 0x2: // lwupc 1878 return SignalContext::READ; 1879 } 1880#endif 1881 } 1882 return SignalContext::UNKNOWN; 1883#elif defined(__arm__) && !SANITIZER_NETBSD 1884 static const uptr FSR_WRITE = 1U << 11; 1885 uptr fsr = ucontext->uc_mcontext.error_code; 1886 return fsr & FSR_WRITE ? WRITE : READ; 1887#elif defined(__aarch64__) 1888 static const u64 ESR_ELx_WNR = 1U << 6; 1889 u64 esr; 1890 if (!Aarch64GetESR(ucontext, &esr)) return UNKNOWN; 1891 return esr & ESR_ELx_WNR ? WRITE : READ; 1892#elif defined(__sparc__) 1893 // Decode the instruction to determine the access type. 1894 // From OpenSolaris $SRC/uts/sun4/os/trap.c (get_accesstype). 1895#if SANITIZER_SOLARIS 1896 uptr pc = ucontext->uc_mcontext.gregs[REG_PC]; 1897#elif SANITIZER_NETBSD 1898 uptr pc = ucontext->uc_mcontext.__gregs[_REG_PC]; 1899#else 1900 // Historical BSDism here. 1901 struct sigcontext *scontext = (struct sigcontext *)context; 1902#if defined(__arch64__) 1903 uptr pc = scontext->sigc_regs.tpc; 1904#else 1905 uptr pc = scontext->si_regs.pc; 1906#endif 1907#endif 1908 u32 instr = *(u32 *)pc; 1909 return (instr >> 21) & 1 ? WRITE: READ; 1910#elif defined(__riscv) 1911#if SANITIZER_FREEBSD 1912 unsigned long pc = ucontext->uc_mcontext.mc_gpregs.gp_sepc; 1913#elif SANITIZER_NETBSD 1914 uptr pc = ucontext->uc_mcontext.__gregs[_REG_PC]; 1915#else 1916 unsigned long pc = ucontext->uc_mcontext.__gregs[REG_PC]; 1917#endif 1918 unsigned faulty_instruction = *(uint16_t *)pc; 1919 1920#if defined(__riscv_compressed) 1921 if ((faulty_instruction & 0x3) != 0x3) { // it's a compressed instruction 1922 // set op_bits to the instruction bits [1, 0, 15, 14, 13] 1923 unsigned op_bits = 1924 ((faulty_instruction & 0x3) << 3) | (faulty_instruction >> 13); 1925 unsigned rd = faulty_instruction & 0xF80; // bits 7-11, inclusive 1926 switch (op_bits) { 1927 case 0b10'010: // c.lwsp (rd != x0) 1928#if __riscv_xlen == 64 1929 case 0b10'011: // c.ldsp (rd != x0) 1930#endif 1931 return rd ? SignalContext::READ : SignalContext::UNKNOWN; 1932 case 0b00'010: // c.lw 1933#if __riscv_flen >= 32 && __riscv_xlen == 32 1934 case 0b10'011: // c.flwsp 1935#endif 1936#if __riscv_flen >= 32 || __riscv_xlen == 64 1937 case 0b00'011: // c.flw / c.ld 1938#endif 1939#if __riscv_flen == 64 1940 case 0b00'001: // c.fld 1941 case 0b10'001: // c.fldsp 1942#endif 1943 return SignalContext::READ; 1944 case 0b00'110: // c.sw 1945 case 0b10'110: // c.swsp 1946#if __riscv_flen >= 32 || __riscv_xlen == 64 1947 case 0b00'111: // c.fsw / c.sd 1948 case 0b10'111: // c.fswsp / c.sdsp 1949#endif 1950#if __riscv_flen == 64 1951 case 0b00'101: // c.fsd 1952 case 0b10'101: // c.fsdsp 1953#endif 1954 return SignalContext::WRITE; 1955 default: 1956 return SignalContext::UNKNOWN; 1957 } 1958 } 1959#endif 1960 1961 unsigned opcode = faulty_instruction & 0x7f; // lower 7 bits 1962 unsigned funct3 = (faulty_instruction >> 12) & 0x7; // bits 12-14, inclusive 1963 switch (opcode) { 1964 case 0b0000011: // loads 1965 switch (funct3) { 1966 case 0b000: // lb 1967 case 0b001: // lh 1968 case 0b010: // lw 1969#if __riscv_xlen == 64 1970 case 0b011: // ld 1971#endif 1972 case 0b100: // lbu 1973 case 0b101: // lhu 1974 return SignalContext::READ; 1975 default: 1976 return SignalContext::UNKNOWN; 1977 } 1978 case 0b0100011: // stores 1979 switch (funct3) { 1980 case 0b000: // sb 1981 case 0b001: // sh 1982 case 0b010: // sw 1983#if __riscv_xlen == 64 1984 case 0b011: // sd 1985#endif 1986 return SignalContext::WRITE; 1987 default: 1988 return SignalContext::UNKNOWN; 1989 } 1990#if __riscv_flen >= 32 1991 case 0b0000111: // floating-point loads 1992 switch (funct3) { 1993 case 0b010: // flw 1994#if __riscv_flen == 64 1995 case 0b011: // fld 1996#endif 1997 return SignalContext::READ; 1998 default: 1999 return SignalContext::UNKNOWN; 2000 } 2001 case 0b0100111: // floating-point stores 2002 switch (funct3) { 2003 case 0b010: // fsw 2004#if __riscv_flen == 64 2005 case 0b011: // fsd 2006#endif 2007 return SignalContext::WRITE; 2008 default: 2009 return SignalContext::UNKNOWN; 2010 } 2011#endif 2012 default: 2013 return SignalContext::UNKNOWN; 2014 } 2015#else 2016 (void)ucontext; 2017 return UNKNOWN; // FIXME: Implement. 2018#endif 2019} 2020 2021bool SignalContext::IsTrueFaultingAddress() const { 2022 auto si = static_cast<const siginfo_t *>(siginfo); 2023 // SIGSEGV signals without a true fault address have si_code set to 128. 2024 return si->si_signo == SIGSEGV && si->si_code != 128; 2025} 2026 2027void SignalContext::DumpAllRegisters(void *context) { 2028 // FIXME: Implement this. 2029} 2030 2031static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) { 2032#if SANITIZER_NETBSD 2033 // This covers all NetBSD architectures 2034 ucontext_t *ucontext = (ucontext_t *)context; 2035 *pc = _UC_MACHINE_PC(ucontext); 2036 *bp = _UC_MACHINE_FP(ucontext); 2037 *sp = _UC_MACHINE_SP(ucontext); 2038#elif defined(__arm__) 2039 ucontext_t *ucontext = (ucontext_t*)context; 2040 *pc = ucontext->uc_mcontext.arm_pc; 2041 *bp = ucontext->uc_mcontext.arm_fp; 2042 *sp = ucontext->uc_mcontext.arm_sp; 2043#elif defined(__aarch64__) 2044 ucontext_t *ucontext = (ucontext_t*)context; 2045 *pc = ucontext->uc_mcontext.pc; 2046 *bp = ucontext->uc_mcontext.regs[29]; 2047 *sp = ucontext->uc_mcontext.sp; 2048#elif defined(__hppa__) 2049 ucontext_t *ucontext = (ucontext_t*)context; 2050 *pc = ucontext->uc_mcontext.sc_iaoq[0]; 2051 /* GCC uses %r3 whenever a frame pointer is needed. */ 2052 *bp = ucontext->uc_mcontext.sc_gr[3]; 2053 *sp = ucontext->uc_mcontext.sc_gr[30]; 2054#elif defined(__x86_64__) 2055# if SANITIZER_FREEBSD 2056 ucontext_t *ucontext = (ucontext_t*)context; 2057 *pc = ucontext->uc_mcontext.mc_rip; 2058 *bp = ucontext->uc_mcontext.mc_rbp; 2059 *sp = ucontext->uc_mcontext.mc_rsp; 2060# else 2061 ucontext_t *ucontext = (ucontext_t*)context; 2062 *pc = ucontext->uc_mcontext.gregs[REG_RIP]; 2063 *bp = ucontext->uc_mcontext.gregs[REG_RBP]; 2064 *sp = ucontext->uc_mcontext.gregs[REG_RSP]; 2065# endif 2066#elif defined(__i386__) 2067# if SANITIZER_FREEBSD 2068 ucontext_t *ucontext = (ucontext_t*)context; 2069 *pc = ucontext->uc_mcontext.mc_eip; 2070 *bp = ucontext->uc_mcontext.mc_ebp; 2071 *sp = ucontext->uc_mcontext.mc_esp; 2072# else 2073 ucontext_t *ucontext = (ucontext_t*)context; 2074# if SANITIZER_SOLARIS 2075 /* Use the numeric values: the symbolic ones are undefined by llvm 2076 include/llvm/Support/Solaris.h. */ 2077# ifndef REG_EIP 2078# define REG_EIP 14 // REG_PC 2079# endif 2080# ifndef REG_EBP 2081# define REG_EBP 6 // REG_FP 2082# endif 2083# ifndef REG_UESP 2084# define REG_UESP 17 // REG_SP 2085# endif 2086# endif 2087 *pc = ucontext->uc_mcontext.gregs[REG_EIP]; 2088 *bp = ucontext->uc_mcontext.gregs[REG_EBP]; 2089 *sp = ucontext->uc_mcontext.gregs[REG_UESP]; 2090# endif 2091#elif defined(__powerpc__) || defined(__powerpc64__) 2092 ucontext_t *ucontext = (ucontext_t*)context; 2093 *pc = ucontext->uc_mcontext.regs->nip; 2094 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1]; 2095 // The powerpc{,64}-linux ABIs do not specify r31 as the frame 2096 // pointer, but GCC always uses r31 when we need a frame pointer. 2097 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31]; 2098#elif defined(__sparc__) 2099#if defined(__arch64__) || defined(__sparcv9) 2100#define STACK_BIAS 2047 2101#else 2102#define STACK_BIAS 0 2103# endif 2104# if SANITIZER_SOLARIS 2105 ucontext_t *ucontext = (ucontext_t *)context; 2106 *pc = ucontext->uc_mcontext.gregs[REG_PC]; 2107 *sp = ucontext->uc_mcontext.gregs[REG_O6] + STACK_BIAS; 2108#else 2109 // Historical BSDism here. 2110 struct sigcontext *scontext = (struct sigcontext *)context; 2111#if defined(__arch64__) 2112 *pc = scontext->sigc_regs.tpc; 2113 *sp = scontext->sigc_regs.u_regs[14] + STACK_BIAS; 2114#else 2115 *pc = scontext->si_regs.pc; 2116 *sp = scontext->si_regs.u_regs[14]; 2117#endif 2118# endif 2119 *bp = (uptr)((uhwptr *)*sp)[14] + STACK_BIAS; 2120#elif defined(__mips__) 2121 ucontext_t *ucontext = (ucontext_t*)context; 2122 *pc = ucontext->uc_mcontext.pc; 2123 *bp = ucontext->uc_mcontext.gregs[30]; 2124 *sp = ucontext->uc_mcontext.gregs[29]; 2125#elif defined(__s390__) 2126 ucontext_t *ucontext = (ucontext_t*)context; 2127# if defined(__s390x__) 2128 *pc = ucontext->uc_mcontext.psw.addr; 2129# else 2130 *pc = ucontext->uc_mcontext.psw.addr & 0x7fffffff; 2131# endif 2132 *bp = ucontext->uc_mcontext.gregs[11]; 2133 *sp = ucontext->uc_mcontext.gregs[15]; 2134#elif defined(__riscv) 2135 ucontext_t *ucontext = (ucontext_t*)context; 2136# if SANITIZER_FREEBSD 2137 *pc = ucontext->uc_mcontext.mc_gpregs.gp_sepc; 2138 *bp = ucontext->uc_mcontext.mc_gpregs.gp_s[0]; 2139 *sp = ucontext->uc_mcontext.mc_gpregs.gp_sp; 2140# else 2141 *pc = ucontext->uc_mcontext.__gregs[REG_PC]; 2142 *bp = ucontext->uc_mcontext.__gregs[REG_S0]; 2143 *sp = ucontext->uc_mcontext.__gregs[REG_SP]; 2144# endif 2145# elif defined(__hexagon__) 2146 ucontext_t *ucontext = (ucontext_t *)context; 2147 *pc = ucontext->uc_mcontext.pc; 2148 *bp = ucontext->uc_mcontext.r30; 2149 *sp = ucontext->uc_mcontext.r29; 2150# else 2151# error "Unsupported arch" 2152# endif 2153} 2154 2155void SignalContext::InitPcSpBp() { GetPcSpBp(context, &pc, &sp, &bp); } 2156 2157void InitializePlatformEarly() { 2158 // Do nothing. 2159} 2160 2161void MaybeReexec() { 2162 // No need to re-exec on Linux. 2163} 2164 2165void CheckASLR() { 2166#if SANITIZER_NETBSD 2167 int mib[3]; 2168 int paxflags; 2169 uptr len = sizeof(paxflags); 2170 2171 mib[0] = CTL_PROC; 2172 mib[1] = internal_getpid(); 2173 mib[2] = PROC_PID_PAXFLAGS; 2174 2175 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2176 Printf("sysctl failed\n"); 2177 Die(); 2178 } 2179 2180 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_ASLR)) { 2181 Printf("This sanitizer is not compatible with enabled ASLR.\n" 2182 "To disable ASLR, please run \"paxctl +a %s\" and try again.\n", 2183 GetArgv()[0]); 2184 Die(); 2185 } 2186#elif SANITIZER_PPC64V2 2187 // Disable ASLR for Linux PPC64LE. 2188 int old_personality = personality(0xffffffff); 2189 if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) { 2190 VReport(1, "WARNING: Program is being run with address space layout " 2191 "randomization (ASLR) enabled which prevents the thread and " 2192 "memory sanitizers from working on powerpc64le.\n" 2193 "ASLR will be disabled and the program re-executed.\n"); 2194 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1); 2195 ReExec(); 2196 } 2197#elif SANITIZER_FREEBSD 2198 int aslr_pie; 2199 uptr len = sizeof(aslr_pie); 2200#if SANITIZER_WORDSIZE == 64 2201 if (UNLIKELY(internal_sysctlbyname("kern.elf64.aslr.pie_enable", 2202 &aslr_pie, &len, NULL, 0) == -1)) { 2203 // We're making things less 'dramatic' here since 2204 // the OID is not necessarily guaranteed to be here 2205 // just yet regarding FreeBSD release 2206 return; 2207 } 2208 2209 if (aslr_pie > 0) { 2210 Printf("This sanitizer is not compatible with enabled ASLR " 2211 "and binaries compiled with PIE\n"); 2212 Die(); 2213 } 2214#endif 2215 // there might be 32 bits compat for 64 bits 2216 if (UNLIKELY(internal_sysctlbyname("kern.elf32.aslr.pie_enable", 2217 &aslr_pie, &len, NULL, 0) == -1)) { 2218 return; 2219 } 2220 2221 if (aslr_pie > 0) { 2222 Printf("This sanitizer is not compatible with enabled ASLR " 2223 "and binaries compiled with PIE\n"); 2224 Die(); 2225 } 2226#else 2227 // Do nothing 2228#endif 2229} 2230 2231void CheckMPROTECT() { 2232#if SANITIZER_NETBSD 2233 int mib[3]; 2234 int paxflags; 2235 uptr len = sizeof(paxflags); 2236 2237 mib[0] = CTL_PROC; 2238 mib[1] = internal_getpid(); 2239 mib[2] = PROC_PID_PAXFLAGS; 2240 2241 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) { 2242 Printf("sysctl failed\n"); 2243 Die(); 2244 } 2245 2246 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_MPROTECT)) { 2247 Printf("This sanitizer is not compatible with enabled MPROTECT\n"); 2248 Die(); 2249 } 2250#else 2251 // Do nothing 2252#endif 2253} 2254 2255void CheckNoDeepBind(const char *filename, int flag) { 2256#ifdef RTLD_DEEPBIND 2257 if (flag & RTLD_DEEPBIND) { 2258 Report( 2259 "You are trying to dlopen a %s shared library with RTLD_DEEPBIND flag" 2260 " which is incompatible with sanitizer runtime " 2261 "(see https://github.com/google/sanitizers/issues/611 for details" 2262 "). If you want to run %s library under sanitizers please remove " 2263 "RTLD_DEEPBIND from dlopen flags.\n", 2264 filename, filename); 2265 Die(); 2266 } 2267#endif 2268} 2269 2270uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding, 2271 uptr *largest_gap_found, 2272 uptr *max_occupied_addr) { 2273 UNREACHABLE("FindAvailableMemoryRange is not available"); 2274 return 0; 2275} 2276 2277bool GetRandom(void *buffer, uptr length, bool blocking) { 2278 if (!buffer || !length || length > 256) 2279 return false; 2280#if SANITIZER_USE_GETENTROPY 2281 uptr rnd = getentropy(buffer, length); 2282 int rverrno = 0; 2283 if (internal_iserror(rnd, &rverrno) && rverrno == EFAULT) 2284 return false; 2285 else if (rnd == 0) 2286 return true; 2287#endif // SANITIZER_USE_GETENTROPY 2288 2289#if SANITIZER_USE_GETRANDOM 2290 static atomic_uint8_t skip_getrandom_syscall; 2291 if (!atomic_load_relaxed(&skip_getrandom_syscall)) { 2292 // Up to 256 bytes, getrandom will not be interrupted. 2293 uptr res = internal_syscall(SYSCALL(getrandom), buffer, length, 2294 blocking ? 0 : GRND_NONBLOCK); 2295 int rverrno = 0; 2296 if (internal_iserror(res, &rverrno) && rverrno == ENOSYS) 2297 atomic_store_relaxed(&skip_getrandom_syscall, 1); 2298 else if (res == length) 2299 return true; 2300 } 2301#endif // SANITIZER_USE_GETRANDOM 2302 // Up to 256 bytes, a read off /dev/urandom will not be interrupted. 2303 // blocking is moot here, O_NONBLOCK has no effect when opening /dev/urandom. 2304 uptr fd = internal_open("/dev/urandom", O_RDONLY); 2305 if (internal_iserror(fd)) 2306 return false; 2307 uptr res = internal_read(fd, buffer, length); 2308 if (internal_iserror(res)) 2309 return false; 2310 internal_close(fd); 2311 return true; 2312} 2313 2314} // namespace __sanitizer 2315 2316#endif 2317