1 //===-- sanitizer_linux.cc ------------------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is shared between AddressSanitizer and ThreadSanitizer
11 // run-time libraries and implements linux-specific functions from
13 //===----------------------------------------------------------------------===//
15 #include "sanitizer_platform.h"
17 #if SANITIZER_FREEBSD || SANITIZER_LINUX
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"
30 #if !SANITIZER_FREEBSD
31 #include <asm/param.h>
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.
39 #include <asm/unistd.h>
40 #include <sys/types.h>
41 #define stat kernel_stat
53 #include <sys/ptrace.h>
54 #include <sys/resource.h>
56 #include <sys/syscall.h>
58 #include <sys/types.h>
63 #include <sys/sysctl.h>
64 #include <machine/atomic.h>
66 // <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on
67 // FreeBSD 9.2 and 10.0.
70 extern char **environ; // provided by crt1
71 #endif // SANITIZER_FREEBSD
73 #if !SANITIZER_ANDROID
74 #include <sys/signal.h>
79 struct kernel_timeval {
84 // <linux/futex.h> is broken on some linux distributions.
85 const int FUTEX_WAIT = 0;
86 const int FUTEX_WAKE = 1;
87 #endif // SANITIZER_LINUX
89 // Are we using 32-bit or 64-bit Linux syscalls?
90 // x32 (which defines __x86_64__) has SANITIZER_WORDSIZE == 32
91 // but it still needs to use 64-bit syscalls.
92 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__powerpc64__) || \
93 SANITIZER_WORDSIZE == 64)
94 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 1
96 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 0
99 namespace __sanitizer {
101 #if SANITIZER_LINUX && defined(__x86_64__)
102 #include "sanitizer_syscall_linux_x86_64.inc"
103 #elif SANITIZER_LINUX && defined(__aarch64__)
104 #include "sanitizer_syscall_linux_aarch64.inc"
106 #include "sanitizer_syscall_generic.inc"
109 // --------------- sanitizer_libc.h
110 uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd,
112 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS
113 return internal_syscall(SYSCALL(mmap), (uptr)addr, length, prot, flags, fd,
116 // mmap2 specifies file offset in 4096-byte units.
117 CHECK(IsAligned(offset, 4096));
118 return internal_syscall(SYSCALL(mmap2), addr, length, prot, flags, fd,
123 uptr internal_munmap(void *addr, uptr length) {
124 return internal_syscall(SYSCALL(munmap), (uptr)addr, length);
127 int internal_mprotect(void *addr, uptr length, int prot) {
128 return internal_syscall(SYSCALL(mprotect), (uptr)addr, length, prot);
131 uptr internal_close(fd_t fd) {
132 return internal_syscall(SYSCALL(close), fd);
135 uptr internal_open(const char *filename, int flags) {
136 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
137 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags);
139 return internal_syscall(SYSCALL(open), (uptr)filename, flags);
143 uptr internal_open(const char *filename, int flags, u32 mode) {
144 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
145 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags,
148 return internal_syscall(SYSCALL(open), (uptr)filename, flags, mode);
152 uptr internal_read(fd_t fd, void *buf, uptr count) {
154 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(read), fd, (uptr)buf,
159 uptr internal_write(fd_t fd, const void *buf, uptr count) {
161 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(write), fd, (uptr)buf,
166 uptr internal_ftruncate(fd_t fd, uptr size) {
168 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(ftruncate), fd,
173 #if !SANITIZER_LINUX_USES_64BIT_SYSCALLS && !SANITIZER_FREEBSD
174 static void stat64_to_stat(struct stat64 *in, struct stat *out) {
175 internal_memset(out, 0, sizeof(*out));
176 out->st_dev = in->st_dev;
177 out->st_ino = in->st_ino;
178 out->st_mode = in->st_mode;
179 out->st_nlink = in->st_nlink;
180 out->st_uid = in->st_uid;
181 out->st_gid = in->st_gid;
182 out->st_rdev = in->st_rdev;
183 out->st_size = in->st_size;
184 out->st_blksize = in->st_blksize;
185 out->st_blocks = in->st_blocks;
186 out->st_atime = in->st_atime;
187 out->st_mtime = in->st_mtime;
188 out->st_ctime = in->st_ctime;
189 out->st_ino = in->st_ino;
193 #if defined(__mips64)
194 static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) {
195 internal_memset(out, 0, sizeof(*out));
196 out->st_dev = in->st_dev;
197 out->st_ino = in->st_ino;
198 out->st_mode = in->st_mode;
199 out->st_nlink = in->st_nlink;
200 out->st_uid = in->st_uid;
201 out->st_gid = in->st_gid;
202 out->st_rdev = in->st_rdev;
203 out->st_size = in->st_size;
204 out->st_blksize = in->st_blksize;
205 out->st_blocks = in->st_blocks;
206 out->st_atime = in->st_atime_nsec;
207 out->st_mtime = in->st_mtime_nsec;
208 out->st_ctime = in->st_ctime_nsec;
209 out->st_ino = in->st_ino;
213 uptr internal_stat(const char *path, void *buf) {
214 #if SANITIZER_FREEBSD
215 return internal_syscall(SYSCALL(stat), path, buf);
216 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
217 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path,
219 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS
220 # if defined(__mips64)
221 // For mips64, stat syscall fills buffer in the format of kernel_stat
222 struct kernel_stat kbuf;
223 int res = internal_syscall(SYSCALL(stat), path, &kbuf);
224 kernel_stat_to_stat(&kbuf, (struct stat *)buf);
227 return internal_syscall(SYSCALL(stat), (uptr)path, (uptr)buf);
231 int res = internal_syscall(SYSCALL(stat64), path, &buf64);
232 stat64_to_stat(&buf64, (struct stat *)buf);
237 uptr internal_lstat(const char *path, void *buf) {
238 #if SANITIZER_FREEBSD
239 return internal_syscall(SYSCALL(lstat), path, buf);
240 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
241 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path,
242 (uptr)buf, AT_SYMLINK_NOFOLLOW);
243 #elif SANITIZER_LINUX_USES_64BIT_SYSCALLS
244 return internal_syscall(SYSCALL(lstat), (uptr)path, (uptr)buf);
247 int res = internal_syscall(SYSCALL(lstat64), path, &buf64);
248 stat64_to_stat(&buf64, (struct stat *)buf);
253 uptr internal_fstat(fd_t fd, void *buf) {
254 #if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS
255 return internal_syscall(SYSCALL(fstat), fd, (uptr)buf);
258 int res = internal_syscall(SYSCALL(fstat64), fd, &buf64);
259 stat64_to_stat(&buf64, (struct stat *)buf);
264 uptr internal_filesize(fd_t fd) {
266 if (internal_fstat(fd, &st))
268 return (uptr)st.st_size;
271 uptr internal_dup2(int oldfd, int newfd) {
272 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
273 return internal_syscall(SYSCALL(dup3), oldfd, newfd, 0);
275 return internal_syscall(SYSCALL(dup2), oldfd, newfd);
279 uptr internal_readlink(const char *path, char *buf, uptr bufsize) {
280 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
281 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD,
282 (uptr)path, (uptr)buf, bufsize);
284 return internal_syscall(SYSCALL(readlink), (uptr)path, (uptr)buf, bufsize);
288 uptr internal_unlink(const char *path) {
289 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
290 return internal_syscall(SYSCALL(unlinkat), AT_FDCWD, (uptr)path, 0);
292 return internal_syscall(SYSCALL(unlink), (uptr)path);
296 uptr internal_rename(const char *oldpath, const char *newpath) {
297 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
298 return internal_syscall(SYSCALL(renameat), AT_FDCWD, (uptr)oldpath, AT_FDCWD,
301 return internal_syscall(SYSCALL(rename), (uptr)oldpath, (uptr)newpath);
305 uptr internal_sched_yield() {
306 return internal_syscall(SYSCALL(sched_yield));
309 void internal__exit(int exitcode) {
310 #if SANITIZER_FREEBSD
311 internal_syscall(SYSCALL(exit), exitcode);
313 internal_syscall(SYSCALL(exit_group), exitcode);
315 Die(); // Unreachable.
318 uptr internal_execve(const char *filename, char *const argv[],
319 char *const envp[]) {
320 return internal_syscall(SYSCALL(execve), (uptr)filename, (uptr)argv,
324 // ----------------- sanitizer_common.h
325 bool FileExists(const char *filename) {
327 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
328 if (internal_syscall(SYSCALL(newfstatat), AT_FDCWD, filename, &st, 0))
330 if (internal_stat(filename, &st))
333 // Sanity check: filename is a regular file.
334 return S_ISREG(st.st_mode);
338 #if SANITIZER_FREEBSD
339 return (uptr)pthread_self();
341 return internal_syscall(SYSCALL(gettid));
346 #if SANITIZER_FREEBSD
351 internal_memset(&tv, 0, sizeof(tv));
352 internal_syscall(SYSCALL(gettimeofday), (uptr)&tv, 0);
353 return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000;
356 // Like getenv, but reads env directly from /proc (on Linux) or parses the
357 // 'environ' array (on FreeBSD) and does not use libc. This function should be
358 // called first inside __asan_init.
359 const char *GetEnv(const char *name) {
360 #if SANITIZER_FREEBSD
361 if (::environ != 0) {
362 uptr NameLen = internal_strlen(name);
363 for (char **Env = ::environ; *Env != 0; Env++) {
364 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=')
365 return (*Env) + NameLen + 1;
368 return 0; // Not found.
369 #elif SANITIZER_LINUX
370 static char *environ;
376 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len))
379 if (!environ || len == 0) return nullptr;
380 uptr namelen = internal_strlen(name);
381 const char *p = environ;
382 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer
383 // proc file has the format NAME=value\0NAME=value\0NAME=value\0...
385 (char*)internal_memchr(p, '\0', len - (p - environ));
386 if (!endp) // this entry isn't NUL terminated
388 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match.
389 return p + namelen + 1; // point after =
392 return nullptr; // Not found.
394 #error "Unsupported platform"
399 SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end;
403 static void ReadNullSepFileToArray(const char *path, char ***arr,
408 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray");
409 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) {
415 for (count = 1, i = 1; ; i++) {
417 if (buff[i+1] == 0) break;
418 (*arr)[count] = &buff[i+1];
419 CHECK_LE(count, arr_size - 1); // FIXME: make this more flexible.
423 (*arr)[count] = nullptr;
427 static void GetArgsAndEnv(char*** argv, char*** envp) {
429 if (&__libc_stack_end) {
431 uptr* stack_end = (uptr*)__libc_stack_end;
432 int argc = *stack_end;
433 *argv = (char**)(stack_end + 1);
434 *envp = (char**)(stack_end + argc + 2);
437 static const int kMaxArgv = 2000, kMaxEnvp = 2000;
438 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv);
439 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp);
446 GetArgsAndEnv(&argv, &envp);
447 uptr rv = internal_execve("/proc/self/exe", argv, envp);
449 CHECK_EQ(internal_iserror(rv, &rverrno), true);
450 Printf("execve failed, errno %d\n", rverrno);
460 BlockingMutex::BlockingMutex() {
461 internal_memset(this, 0, sizeof(*this));
464 void BlockingMutex::Lock() {
466 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_);
467 if (atomic_exchange(m, MtxLocked, memory_order_acquire) == MtxUnlocked)
469 while (atomic_exchange(m, MtxSleeping, memory_order_acquire) != MtxUnlocked) {
470 #if SANITIZER_FREEBSD
471 _umtx_op(m, UMTX_OP_WAIT_UINT, MtxSleeping, 0, 0);
473 internal_syscall(SYSCALL(futex), (uptr)m, FUTEX_WAIT, MtxSleeping, 0, 0, 0);
478 void BlockingMutex::Unlock() {
479 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_);
480 u32 v = atomic_exchange(m, MtxUnlocked, memory_order_relaxed);
481 CHECK_NE(v, MtxUnlocked);
482 if (v == MtxSleeping) {
483 #if SANITIZER_FREEBSD
484 _umtx_op(m, UMTX_OP_WAKE, 1, 0, 0);
486 internal_syscall(SYSCALL(futex), (uptr)m, FUTEX_WAKE, 1, 0, 0, 0);
491 void BlockingMutex::CheckLocked() {
492 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_);
493 CHECK_NE(MtxUnlocked, atomic_load(m, memory_order_relaxed));
496 // ----------------- sanitizer_linux.h
497 // The actual size of this structure is specified by d_reclen.
498 // Note that getdents64 uses a different structure format. We only provide the
499 // 32-bit syscall here.
500 struct linux_dirent {
501 #if SANITIZER_X32 || defined(__aarch64__)
508 unsigned short d_reclen;
510 unsigned char d_type;
516 uptr internal_ptrace(int request, int pid, void *addr, void *data) {
517 return internal_syscall(SYSCALL(ptrace), request, pid, (uptr)addr,
521 uptr internal_waitpid(int pid, int *status, int options) {
522 return internal_syscall(SYSCALL(wait4), pid, (uptr)status, options,
526 uptr internal_getpid() {
527 return internal_syscall(SYSCALL(getpid));
530 uptr internal_getppid() {
531 return internal_syscall(SYSCALL(getppid));
534 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) {
535 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
536 return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count);
538 return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count);
542 uptr internal_lseek(fd_t fd, OFF_T offset, int whence) {
543 return internal_syscall(SYSCALL(lseek), fd, offset, whence);
547 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) {
548 return internal_syscall(SYSCALL(prctl), option, arg2, arg3, arg4, arg5);
552 uptr internal_sigaltstack(const struct sigaltstack *ss,
553 struct sigaltstack *oss) {
554 return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss);
557 int internal_fork() {
558 #if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
559 return internal_syscall(SYSCALL(clone), SIGCHLD, 0);
561 return internal_syscall(SYSCALL(fork));
566 #define SA_RESTORER 0x04000000
567 // Doesn't set sa_restorer, use with caution (see below).
568 int internal_sigaction_norestorer(int signum, const void *act, void *oldact) {
569 __sanitizer_kernel_sigaction_t k_act, k_oldact;
570 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t));
571 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t));
572 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act;
573 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact;
575 k_act.handler = u_act->handler;
576 k_act.sigaction = u_act->sigaction;
577 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask,
578 sizeof(__sanitizer_kernel_sigset_t));
579 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL).
580 k_act.sa_flags = u_act->sa_flags | SA_RESTORER;
581 // FIXME: most often sa_restorer is unset, however the kernel requires it
582 // to point to a valid signal restorer that calls the rt_sigreturn syscall.
583 // If sa_restorer passed to the kernel is NULL, the program may crash upon
584 // signal delivery or fail to unwind the stack in the signal handler.
585 // libc implementation of sigaction() passes its own restorer to
586 // rt_sigaction, so we need to do the same (we'll need to reimplement the
587 // restorers; for x86_64 the restorer address can be obtained from
588 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact).
589 k_act.sa_restorer = u_act->sa_restorer;
592 uptr result = internal_syscall(SYSCALL(rt_sigaction), (uptr)signum,
593 (uptr)(u_act ? &k_act : nullptr),
594 (uptr)(u_oldact ? &k_oldact : nullptr),
595 (uptr)sizeof(__sanitizer_kernel_sigset_t));
597 if ((result == 0) && u_oldact) {
598 u_oldact->handler = k_oldact.handler;
599 u_oldact->sigaction = k_oldact.sigaction;
600 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask,
601 sizeof(__sanitizer_kernel_sigset_t));
602 u_oldact->sa_flags = k_oldact.sa_flags;
603 u_oldact->sa_restorer = k_oldact.sa_restorer;
607 #endif // SANITIZER_LINUX
609 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
610 __sanitizer_sigset_t *oldset) {
611 #if SANITIZER_FREEBSD
612 return internal_syscall(SYSCALL(sigprocmask), how, set, oldset);
614 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set;
615 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset;
616 return internal_syscall(SYSCALL(rt_sigprocmask), (uptr)how,
617 (uptr)&k_set->sig[0], (uptr)&k_oldset->sig[0],
618 sizeof(__sanitizer_kernel_sigset_t));
622 void internal_sigfillset(__sanitizer_sigset_t *set) {
623 internal_memset(set, 0xff, sizeof(*set));
627 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) {
630 CHECK_LT(signum, sizeof(*set) * 8);
631 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set;
632 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8);
633 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8);
634 k_set->sig[idx] &= ~(1 << bit);
636 #endif // SANITIZER_LINUX
638 // ThreadLister implementation.
639 ThreadLister::ThreadLister(int pid)
644 entry_((struct linux_dirent *)buffer_.data()),
646 char task_directory_path[80];
647 internal_snprintf(task_directory_path, sizeof(task_directory_path),
648 "/proc/%d/task/", pid);
649 uptr openrv = internal_open(task_directory_path, O_RDONLY | O_DIRECTORY);
650 if (internal_iserror(openrv)) {
652 Report("Can't open /proc/%d/task for reading.\n", pid);
655 descriptor_ = openrv;
659 int ThreadLister::GetNextTID() {
664 if ((char *)entry_ >= &buffer_[bytes_read_] && !GetDirectoryEntries())
666 if (entry_->d_ino != 0 && entry_->d_name[0] >= '0' &&
667 entry_->d_name[0] <= '9') {
668 // Found a valid tid.
669 tid = (int)internal_atoll(entry_->d_name);
671 entry_ = (struct linux_dirent *)(((char *)entry_) + entry_->d_reclen);
676 void ThreadLister::Reset() {
677 if (error_ || descriptor_ < 0)
679 internal_lseek(descriptor_, 0, SEEK_SET);
682 ThreadLister::~ThreadLister() {
683 if (descriptor_ >= 0)
684 internal_close(descriptor_);
687 bool ThreadLister::error() { return error_; }
689 bool ThreadLister::GetDirectoryEntries() {
690 CHECK_GE(descriptor_, 0);
691 CHECK_NE(error_, true);
692 bytes_read_ = internal_getdents(descriptor_,
693 (struct linux_dirent *)buffer_.data(),
695 if (internal_iserror(bytes_read_)) {
696 Report("Can't read directory entries from /proc/%d/task.\n", pid_);
699 } else if (bytes_read_ == 0) {
702 entry_ = (struct linux_dirent *)buffer_.data();
707 #if SANITIZER_LINUX && (defined(__x86_64__) || defined(__i386__))
708 return EXEC_PAGESIZE;
710 return sysconf(_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy.
714 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) {
715 #if SANITIZER_FREEBSD
716 const int Mib[] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1 };
717 const char *default_module_name = "kern.proc.pathname";
718 size_t Size = buf_len;
719 bool IsErr = (sysctl(Mib, ARRAY_SIZE(Mib), buf, &Size, NULL, 0) != 0);
720 int readlink_error = IsErr ? errno : 0;
721 uptr module_name_len = Size;
723 const char *default_module_name = "/proc/self/exe";
724 uptr module_name_len = internal_readlink(
725 default_module_name, buf, buf_len);
727 bool IsErr = internal_iserror(module_name_len, &readlink_error);
730 // We can't read binary name for some reason, assume it's unknown.
731 Report("WARNING: reading executable name failed with errno %d, "
732 "some stack frames may not be symbolized\n", readlink_error);
733 module_name_len = internal_snprintf(buf, buf_len, "%s",
734 default_module_name);
735 CHECK_LT(module_name_len, buf_len);
737 return module_name_len;
740 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) {
745 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen,
747 internal_strncpy(buf, tmpbuf, buf_len);
748 UnmapOrDie(tmpbuf, tmpsize);
749 return internal_strlen(buf);
752 return ReadBinaryName(buf, buf_len);
755 // Match full names of the form /path/to/base_name{-,.}*
756 bool LibraryNameIs(const char *full_name, const char *base_name) {
757 const char *name = full_name;
759 while (*name != '\0') name++;
760 while (name > full_name && *name != '/') name--;
761 if (*name == '/') name++;
762 uptr base_name_length = internal_strlen(base_name);
763 if (internal_strncmp(name, base_name, base_name_length)) return false;
764 return (name[base_name_length] == '-' || name[base_name_length] == '.');
767 #if !SANITIZER_ANDROID
768 // Call cb for each region mapped by map.
769 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) {
770 CHECK_NE(map, nullptr);
771 #if !SANITIZER_FREEBSD
772 typedef ElfW(Phdr) Elf_Phdr;
773 typedef ElfW(Ehdr) Elf_Ehdr;
774 #endif // !SANITIZER_FREEBSD
775 char *base = (char *)map->l_addr;
776 Elf_Ehdr *ehdr = (Elf_Ehdr *)base;
777 char *phdrs = base + ehdr->e_phoff;
778 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize;
780 // Find the segment with the minimum base so we can "relocate" the p_vaddr
781 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC
782 // objects have a non-zero base.
783 uptr preferred_base = (uptr)-1;
784 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) {
785 Elf_Phdr *phdr = (Elf_Phdr *)iter;
786 if (phdr->p_type == PT_LOAD && preferred_base > (uptr)phdr->p_vaddr)
787 preferred_base = (uptr)phdr->p_vaddr;
790 // Compute the delta from the real base to get a relocation delta.
791 sptr delta = (uptr)base - preferred_base;
792 // Now we can figure out what the loader really mapped.
793 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) {
794 Elf_Phdr *phdr = (Elf_Phdr *)iter;
795 if (phdr->p_type == PT_LOAD) {
796 uptr seg_start = phdr->p_vaddr + delta;
797 uptr seg_end = seg_start + phdr->p_memsz;
798 // None of these values are aligned. We consider the ragged edges of the
799 // load command as defined, since they are mapped from the file.
800 seg_start = RoundDownTo(seg_start, GetPageSizeCached());
801 seg_end = RoundUpTo(seg_end, GetPageSizeCached());
802 cb((void *)seg_start, seg_end - seg_start);
808 #if defined(__x86_64__) && SANITIZER_LINUX
809 // We cannot use glibc's clone wrapper, because it messes with the child
810 // task's TLS. It writes the PID and TID of the child task to its thread
811 // descriptor, but in our case the child task shares the thread descriptor with
812 // the parent (because we don't know how to allocate a new thread
813 // descriptor to keep glibc happy). So the stock version of clone(), when
814 // used with CLONE_VM, would end up corrupting the parent's thread descriptor.
815 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
816 int *parent_tidptr, void *newtls, int *child_tidptr) {
818 if (!fn || !child_stack)
820 CHECK_EQ(0, (uptr)child_stack % 16);
821 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
822 ((unsigned long long *)child_stack)[0] = (uptr)fn;
823 ((unsigned long long *)child_stack)[1] = (uptr)arg;
824 register void *r8 __asm__("r8") = newtls;
825 register int *r10 __asm__("r10") = child_tidptr;
826 __asm__ __volatile__(
827 /* %rax = syscall(%rax = SYSCALL(clone),
829 * %rsi = child_stack,
830 * %rdx = parent_tidptr,
832 * %r10 = child_tidptr)
839 "testq %%rax,%%rax\n"
842 /* In the child. Terminate unwind chain. */
843 // XXX: We should also terminate the CFI unwind chain
844 // here. Unfortunately clang 3.2 doesn't support the
845 // necessary CFI directives, so we skip that part.
848 /* Call "fn(arg)". */
853 /* Call _exit(%rax). */
858 /* Return to parent. */
861 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)),
867 : "rsp", "memory", "r11", "rcx");
870 #elif defined(__mips__)
871 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
872 int *parent_tidptr, void *newtls, int *child_tidptr) {
874 if (!fn || !child_stack)
876 CHECK_EQ(0, (uptr)child_stack % 16);
877 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
878 ((unsigned long long *)child_stack)[0] = (uptr)fn;
879 ((unsigned long long *)child_stack)[1] = (uptr)arg;
880 register void *a3 __asm__("$7") = newtls;
881 register int *a4 __asm__("$8") = child_tidptr;
882 // We don't have proper CFI directives here because it requires alot of code
883 // for very marginal benefits.
884 __asm__ __volatile__(
885 /* $v0 = syscall($v0 = __NR_clone,
888 * $a2 = parent_tidptr,
890 * $a4 = child_tidptr)
897 /* Store the fifth argument on stack
898 * if we are using 32-bit abi.
900 #if SANITIZER_WORDSIZE == 32
913 /* Call "fn(arg)". */
918 /* Call _exit($v0). */
923 /* Return to parent. */
936 #elif defined(__aarch64__)
937 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
938 int *parent_tidptr, void *newtls, int *child_tidptr) {
940 if (!fn || !child_stack)
942 CHECK_EQ(0, (uptr)child_stack % 16);
943 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
944 ((unsigned long long *)child_stack)[0] = (uptr)fn;
945 ((unsigned long long *)child_stack)[1] = (uptr)arg;
947 register int (*__fn)(void *) __asm__("x0") = fn;
948 register void *__stack __asm__("x1") = child_stack;
949 register int __flags __asm__("x2") = flags;
950 register void *__arg __asm__("x3") = arg;
951 register int *__ptid __asm__("x4") = parent_tidptr;
952 register void *__tls __asm__("x5") = newtls;
953 register int *__ctid __asm__("x6") = child_tidptr;
955 __asm__ __volatile__(
956 "mov x0,x2\n" /* flags */
957 "mov x2,x4\n" /* ptid */
958 "mov x3,x5\n" /* tls */
959 "mov x4,x6\n" /* ctid */
960 "mov x8,%9\n" /* clone */
970 /* In the child, now. Call "fn(arg)". */
971 "ldp x1, x0, [sp], #16\n"
974 /* Call _exit(%r0). */
981 "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg),
982 "r"(__ptid), "r"(__tls), "r"(__ctid),
983 "i"(__NR_clone), "i"(__NR_exit)
987 #elif defined(__powerpc64__)
988 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
989 int *parent_tidptr, void *newtls, int *child_tidptr) {
991 /* Stack frame offsets. */
993 #define FRAME_MIN_SIZE 112
994 #define FRAME_TOC_SAVE 40
996 #define FRAME_MIN_SIZE 32
997 #define FRAME_TOC_SAVE 24
999 if (!fn || !child_stack)
1001 CHECK_EQ(0, (uptr)child_stack % 16);
1002 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
1003 ((unsigned long long *)child_stack)[0] = (uptr)fn;
1004 ((unsigned long long *)child_stack)[1] = (uptr)arg;
1006 register int (*__fn)(void *) __asm__("r3") = fn;
1007 register void *__cstack __asm__("r4") = child_stack;
1008 register int __flags __asm__("r5") = flags;
1009 register void * __arg __asm__("r6") = arg;
1010 register int * __ptidptr __asm__("r7") = parent_tidptr;
1011 register void * __newtls __asm__("r8") = newtls;
1012 register int * __ctidptr __asm__("r9") = child_tidptr;
1014 __asm__ __volatile__(
1015 /* fn, arg, child_stack are saved acrVoss the syscall */
1025 r7 == child_tidptr */
1033 /* Test if syscall was successful */
1034 "cmpdi cr1, 3, 0\n\t"
1035 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t"
1038 /* Do the function call */
1052 /* Call _exit(r3) */
1056 /* Return to parent */
1060 : "0" (-1), "i" (EINVAL),
1061 "i" (__NR_clone), "i" (__NR_exit),
1062 "r" (__fn), "r" (__cstack), "r" (__flags),
1063 "r" (__arg), "r" (__ptidptr), "r" (__newtls),
1064 "r" (__ctidptr), "i" (FRAME_MIN_SIZE), "i" (FRAME_TOC_SAVE)
1065 : "cr0", "cr1", "memory", "ctr",
1066 "r0", "r29", "r27", "r28");
1069 #endif // defined(__x86_64__) && SANITIZER_LINUX
1071 #if SANITIZER_ANDROID
1072 #if __ANDROID_API__ < 21
1073 extern "C" __attribute__((weak)) int dl_iterate_phdr(
1074 int (*)(struct dl_phdr_info *, size_t, void *), void *);
1077 static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size,
1079 // Any name starting with "lib" indicates a bug in L where library base names
1080 // are returned instead of paths.
1081 if (info->dlpi_name && info->dlpi_name[0] == 'l' &&
1082 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') {
1083 *(bool *)data = true;
1089 static atomic_uint32_t android_api_level;
1091 static AndroidApiLevel AndroidDetectApiLevel() {
1092 if (!&dl_iterate_phdr)
1093 return ANDROID_KITKAT; // K or lower
1094 bool base_name_seen = false;
1095 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen);
1097 return ANDROID_LOLLIPOP_MR1; // L MR1
1098 return ANDROID_POST_LOLLIPOP; // post-L
1099 // Plain L (API level 21) is completely broken wrt ASan and not very
1100 // interesting to detect.
1103 AndroidApiLevel AndroidGetApiLevel() {
1104 AndroidApiLevel level =
1105 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed);
1106 if (level) return level;
1107 level = AndroidDetectApiLevel();
1108 atomic_store(&android_api_level, level, memory_order_relaxed);
1114 bool IsDeadlySignal(int signum) {
1115 if (common_flags()->handle_abort && signum == SIGABRT)
1117 if (common_flags()->handle_sigill && signum == SIGILL)
1119 if (common_flags()->handle_sigfpe && signum == SIGFPE)
1121 return (signum == SIGSEGV || signum == SIGBUS) && common_flags()->handle_segv;
1124 #ifndef SANITIZER_GO
1125 void *internal_start_thread(void(*func)(void *arg), void *arg) {
1126 // Start the thread with signals blocked, otherwise it can steal user signals.
1127 __sanitizer_sigset_t set, old;
1128 internal_sigfillset(&set);
1129 #if SANITIZER_LINUX && !SANITIZER_ANDROID
1130 // Glibc uses SIGSETXID signal during setuid call. If this signal is blocked
1131 // on any thread, setuid call hangs (see test/tsan/setuid.c).
1132 internal_sigdelset(&set, 33);
1134 internal_sigprocmask(SIG_SETMASK, &set, &old);
1136 real_pthread_create(&th, nullptr, (void*(*)(void *arg))func, arg);
1137 internal_sigprocmask(SIG_SETMASK, &old, nullptr);
1141 void internal_join_thread(void *th) {
1142 real_pthread_join(th, nullptr);
1145 void *internal_start_thread(void (*func)(void *), void *arg) { return 0; }
1147 void internal_join_thread(void *th) {}
1150 void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) {
1151 #if defined(__arm__)
1152 ucontext_t *ucontext = (ucontext_t*)context;
1153 *pc = ucontext->uc_mcontext.arm_pc;
1154 *bp = ucontext->uc_mcontext.arm_fp;
1155 *sp = ucontext->uc_mcontext.arm_sp;
1156 #elif defined(__aarch64__)
1157 ucontext_t *ucontext = (ucontext_t*)context;
1158 *pc = ucontext->uc_mcontext.pc;
1159 *bp = ucontext->uc_mcontext.regs[29];
1160 *sp = ucontext->uc_mcontext.sp;
1161 #elif defined(__hppa__)
1162 ucontext_t *ucontext = (ucontext_t*)context;
1163 *pc = ucontext->uc_mcontext.sc_iaoq[0];
1164 /* GCC uses %r3 whenever a frame pointer is needed. */
1165 *bp = ucontext->uc_mcontext.sc_gr[3];
1166 *sp = ucontext->uc_mcontext.sc_gr[30];
1167 #elif defined(__x86_64__)
1168 # if SANITIZER_FREEBSD
1169 ucontext_t *ucontext = (ucontext_t*)context;
1170 *pc = ucontext->uc_mcontext.mc_rip;
1171 *bp = ucontext->uc_mcontext.mc_rbp;
1172 *sp = ucontext->uc_mcontext.mc_rsp;
1174 ucontext_t *ucontext = (ucontext_t*)context;
1175 *pc = ucontext->uc_mcontext.gregs[REG_RIP];
1176 *bp = ucontext->uc_mcontext.gregs[REG_RBP];
1177 *sp = ucontext->uc_mcontext.gregs[REG_RSP];
1179 #elif defined(__i386__)
1180 # if SANITIZER_FREEBSD
1181 ucontext_t *ucontext = (ucontext_t*)context;
1182 *pc = ucontext->uc_mcontext.mc_eip;
1183 *bp = ucontext->uc_mcontext.mc_ebp;
1184 *sp = ucontext->uc_mcontext.mc_esp;
1186 ucontext_t *ucontext = (ucontext_t*)context;
1187 *pc = ucontext->uc_mcontext.gregs[REG_EIP];
1188 *bp = ucontext->uc_mcontext.gregs[REG_EBP];
1189 *sp = ucontext->uc_mcontext.gregs[REG_ESP];
1191 #elif defined(__powerpc__) || defined(__powerpc64__)
1192 ucontext_t *ucontext = (ucontext_t*)context;
1193 *pc = ucontext->uc_mcontext.regs->nip;
1194 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1];
1195 // The powerpc{,64}-linux ABIs do not specify r31 as the frame
1196 // pointer, but GCC always uses r31 when we need a frame pointer.
1197 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31];
1198 #elif defined(__sparc__)
1199 ucontext_t *ucontext = (ucontext_t*)context;
1201 # if defined (__arch64__)
1202 *pc = ucontext->uc_mcontext.mc_gregs[MC_PC];
1203 *sp = ucontext->uc_mcontext.mc_gregs[MC_O6];
1204 stk_ptr = (uptr *) (*sp + 2047);
1207 *pc = ucontext->uc_mcontext.gregs[REG_PC];
1208 *sp = ucontext->uc_mcontext.gregs[REG_O6];
1209 stk_ptr = (uptr *) *sp;
1212 #elif defined(__mips__)
1213 ucontext_t *ucontext = (ucontext_t*)context;
1214 *pc = ucontext->uc_mcontext.pc;
1215 *bp = ucontext->uc_mcontext.gregs[30];
1216 *sp = ucontext->uc_mcontext.gregs[29];
1218 # error "Unsupported arch"
1222 void DisableReexec() {
1223 // No need to re-exec on Linux.
1226 void MaybeReexec() {
1227 // No need to re-exec on Linux.
1230 } // namespace __sanitizer
1232 #endif // SANITIZER_FREEBSD || SANITIZER_LINUX