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_MIPS64
38 # include <asm/unistd.h>
39 # include <sys/types.h>
40 # define stat kernel_stat
41 # if SANITIZER_GO
42 # undef st_atime
43 # undef st_mtime
44 # undef st_ctime
45 # define st_atime st_atim
46 # define st_mtime st_mtim
47 # define st_ctime st_ctim
48 # endif
49 # include <asm/stat.h>
50 # undef stat
51 # endif
52
53 # include <dlfcn.h>
54 # include <errno.h>
55 # include <fcntl.h>
56 # include <link.h>
57 # include <pthread.h>
58 # include <sched.h>
59 # include <signal.h>
60 # include <sys/mman.h>
61 # if !SANITIZER_SOLARIS
62 # include <sys/ptrace.h>
63 # endif
64 # include <sys/resource.h>
65 # include <sys/stat.h>
66 # include <sys/syscall.h>
67 # include <sys/time.h>
68 # include <sys/types.h>
69 # include <ucontext.h>
70 # include <unistd.h>
71
72 # if SANITIZER_LINUX
73 # include <sys/utsname.h>
74 # endif
75
76 # if SANITIZER_LINUX && !SANITIZER_ANDROID
77 # include <sys/personality.h>
78 # endif
79
80 # if SANITIZER_LINUX && defined(__loongarch__)
81 # include <sys/sysmacros.h>
82 # endif
83
84 # if SANITIZER_FREEBSD
85 # include <machine/atomic.h>
86 # include <sys/exec.h>
87 # include <sys/procctl.h>
88 # include <sys/sysctl.h>
89 extern "C" {
90 // <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on
91 // FreeBSD 9.2 and 10.0.
92 # include <sys/umtx.h>
93 }
94 # include <sys/thr.h>
95 # endif // SANITIZER_FREEBSD
96
97 # if SANITIZER_NETBSD
98 # include <limits.h> // For NAME_MAX
99 # include <sys/exec.h>
100 # include <sys/sysctl.h>
101 extern struct ps_strings *__ps_strings;
102 # endif // SANITIZER_NETBSD
103
104 # if SANITIZER_SOLARIS
105 # include <stdlib.h>
106 # include <thread.h>
107 # define environ _environ
108 # endif
109
110 extern char **environ;
111
112 # if SANITIZER_LINUX
113 // <linux/time.h>
114 struct kernel_timeval {
115 long tv_sec;
116 long tv_usec;
117 };
118
119 // <linux/futex.h> is broken on some linux distributions.
120 const int FUTEX_WAIT = 0;
121 const int FUTEX_WAKE = 1;
122 const int FUTEX_PRIVATE_FLAG = 128;
123 const int FUTEX_WAIT_PRIVATE = FUTEX_WAIT | FUTEX_PRIVATE_FLAG;
124 const int FUTEX_WAKE_PRIVATE = FUTEX_WAKE | FUTEX_PRIVATE_FLAG;
125 # endif // SANITIZER_LINUX
126
127 // Are we using 32-bit or 64-bit Linux syscalls?
128 // x32 (which defines __x86_64__) has SANITIZER_WORDSIZE == 32
129 // but it still needs to use 64-bit syscalls.
130 # if SANITIZER_LINUX && (defined(__x86_64__) || defined(__powerpc64__) || \
131 SANITIZER_WORDSIZE == 64 || \
132 (defined(__mips__) && _MIPS_SIM == _ABIN32))
133 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 1
134 # else
135 # define SANITIZER_LINUX_USES_64BIT_SYSCALLS 0
136 # endif
137
138 // Note : FreeBSD implemented both Linux and OpenBSD apis.
139 # if SANITIZER_LINUX && defined(__NR_getrandom)
140 # if !defined(GRND_NONBLOCK)
141 # define GRND_NONBLOCK 1
142 # endif
143 # define SANITIZER_USE_GETRANDOM 1
144 # else
145 # define SANITIZER_USE_GETRANDOM 0
146 # endif // SANITIZER_LINUX && defined(__NR_getrandom)
147
148 # if SANITIZER_FREEBSD
149 # define SANITIZER_USE_GETENTROPY 1
150 # endif
151
152 namespace __sanitizer {
153
SetSigProcMask(__sanitizer_sigset_t * set,__sanitizer_sigset_t * oldset)154 void SetSigProcMask(__sanitizer_sigset_t *set, __sanitizer_sigset_t *oldset) {
155 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, set, oldset));
156 }
157
BlockSignals(__sanitizer_sigset_t * oldset)158 void BlockSignals(__sanitizer_sigset_t *oldset) {
159 __sanitizer_sigset_t set;
160 internal_sigfillset(&set);
161 # if SANITIZER_LINUX && !SANITIZER_ANDROID
162 // Glibc uses SIGSETXID signal during setuid call. If this signal is blocked
163 // on any thread, setuid call hangs.
164 // See test/sanitizer_common/TestCases/Linux/setuid.c.
165 internal_sigdelset(&set, 33);
166 # endif
167 # if SANITIZER_LINUX
168 // Seccomp-BPF-sandboxed processes rely on SIGSYS to handle trapped syscalls.
169 // If this signal is blocked, such calls cannot be handled and the process may
170 // hang.
171 internal_sigdelset(&set, 31);
172 # endif
173 SetSigProcMask(&set, oldset);
174 }
175
ScopedBlockSignals(__sanitizer_sigset_t * copy)176 ScopedBlockSignals::ScopedBlockSignals(__sanitizer_sigset_t *copy) {
177 BlockSignals(&saved_);
178 if (copy)
179 internal_memcpy(copy, &saved_, sizeof(saved_));
180 }
181
~ScopedBlockSignals()182 ScopedBlockSignals::~ScopedBlockSignals() { SetSigProcMask(&saved_, nullptr); }
183
184 # if SANITIZER_LINUX && defined(__x86_64__)
185 # include "sanitizer_syscall_linux_x86_64.inc"
186 # elif SANITIZER_LINUX && SANITIZER_RISCV64
187 # include "sanitizer_syscall_linux_riscv64.inc"
188 # elif SANITIZER_LINUX && defined(__aarch64__)
189 # include "sanitizer_syscall_linux_aarch64.inc"
190 # elif SANITIZER_LINUX && defined(__arm__)
191 # include "sanitizer_syscall_linux_arm.inc"
192 # elif SANITIZER_LINUX && defined(__hexagon__)
193 # include "sanitizer_syscall_linux_hexagon.inc"
194 # elif SANITIZER_LINUX && SANITIZER_LOONGARCH64
195 # include "sanitizer_syscall_linux_loongarch64.inc"
196 # else
197 # include "sanitizer_syscall_generic.inc"
198 # endif
199
200 // --------------- sanitizer_libc.h
201 # if !SANITIZER_SOLARIS && !SANITIZER_NETBSD
202 # if !SANITIZER_S390
internal_mmap(void * addr,uptr length,int prot,int flags,int fd,u64 offset)203 uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd,
204 u64 offset) {
205 # if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS
206 return internal_syscall(SYSCALL(mmap), (uptr)addr, length, prot, flags, fd,
207 offset);
208 # else
209 // mmap2 specifies file offset in 4096-byte units.
210 CHECK(IsAligned(offset, 4096));
211 return internal_syscall(SYSCALL(mmap2), addr, length, prot, flags, fd,
212 offset / 4096);
213 # endif
214 }
215 # endif // !SANITIZER_S390
216
internal_munmap(void * addr,uptr length)217 uptr internal_munmap(void *addr, uptr length) {
218 return internal_syscall(SYSCALL(munmap), (uptr)addr, length);
219 }
220
221 # if SANITIZER_LINUX
internal_mremap(void * old_address,uptr old_size,uptr new_size,int flags,void * new_address)222 uptr internal_mremap(void *old_address, uptr old_size, uptr new_size, int flags,
223 void *new_address) {
224 return internal_syscall(SYSCALL(mremap), (uptr)old_address, old_size,
225 new_size, flags, (uptr)new_address);
226 }
227 # endif
228
internal_mprotect(void * addr,uptr length,int prot)229 int internal_mprotect(void *addr, uptr length, int prot) {
230 return internal_syscall(SYSCALL(mprotect), (uptr)addr, length, prot);
231 }
232
internal_madvise(uptr addr,uptr length,int advice)233 int internal_madvise(uptr addr, uptr length, int advice) {
234 return internal_syscall(SYSCALL(madvise), addr, length, advice);
235 }
236
internal_close(fd_t fd)237 uptr internal_close(fd_t fd) { return internal_syscall(SYSCALL(close), fd); }
238
internal_open(const char * filename,int flags)239 uptr internal_open(const char *filename, int flags) {
240 # if SANITIZER_LINUX
241 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags);
242 # else
243 return internal_syscall(SYSCALL(open), (uptr)filename, flags);
244 # endif
245 }
246
internal_open(const char * filename,int flags,u32 mode)247 uptr internal_open(const char *filename, int flags, u32 mode) {
248 # if SANITIZER_LINUX
249 return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags,
250 mode);
251 # else
252 return internal_syscall(SYSCALL(open), (uptr)filename, flags, mode);
253 # endif
254 }
255
internal_read(fd_t fd,void * buf,uptr count)256 uptr internal_read(fd_t fd, void *buf, uptr count) {
257 sptr res;
258 HANDLE_EINTR(res,
259 (sptr)internal_syscall(SYSCALL(read), fd, (uptr)buf, count));
260 return res;
261 }
262
internal_write(fd_t fd,const void * buf,uptr count)263 uptr internal_write(fd_t fd, const void *buf, uptr count) {
264 sptr res;
265 HANDLE_EINTR(res,
266 (sptr)internal_syscall(SYSCALL(write), fd, (uptr)buf, count));
267 return res;
268 }
269
internal_ftruncate(fd_t fd,uptr size)270 uptr internal_ftruncate(fd_t fd, uptr size) {
271 sptr res;
272 HANDLE_EINTR(res,
273 (sptr)internal_syscall(SYSCALL(ftruncate), fd, (OFF_T)size));
274 return res;
275 }
276
277 # if (!SANITIZER_LINUX_USES_64BIT_SYSCALLS || SANITIZER_SPARC) && \
278 SANITIZER_LINUX
stat64_to_stat(struct stat64 * in,struct stat * out)279 static void stat64_to_stat(struct stat64 *in, struct stat *out) {
280 internal_memset(out, 0, sizeof(*out));
281 out->st_dev = in->st_dev;
282 out->st_ino = in->st_ino;
283 out->st_mode = in->st_mode;
284 out->st_nlink = in->st_nlink;
285 out->st_uid = in->st_uid;
286 out->st_gid = in->st_gid;
287 out->st_rdev = in->st_rdev;
288 out->st_size = in->st_size;
289 out->st_blksize = in->st_blksize;
290 out->st_blocks = in->st_blocks;
291 out->st_atime = in->st_atime;
292 out->st_mtime = in->st_mtime;
293 out->st_ctime = in->st_ctime;
294 }
295 # endif
296
297 # if SANITIZER_LINUX && defined(__loongarch__)
statx_to_stat(struct statx * in,struct stat * out)298 static void statx_to_stat(struct statx *in, struct stat *out) {
299 internal_memset(out, 0, sizeof(*out));
300 out->st_dev = makedev(in->stx_dev_major, in->stx_dev_minor);
301 out->st_ino = in->stx_ino;
302 out->st_mode = in->stx_mode;
303 out->st_nlink = in->stx_nlink;
304 out->st_uid = in->stx_uid;
305 out->st_gid = in->stx_gid;
306 out->st_rdev = makedev(in->stx_rdev_major, in->stx_rdev_minor);
307 out->st_size = in->stx_size;
308 out->st_blksize = in->stx_blksize;
309 out->st_blocks = in->stx_blocks;
310 out->st_atime = in->stx_atime.tv_sec;
311 out->st_atim.tv_nsec = in->stx_atime.tv_nsec;
312 out->st_mtime = in->stx_mtime.tv_sec;
313 out->st_mtim.tv_nsec = in->stx_mtime.tv_nsec;
314 out->st_ctime = in->stx_ctime.tv_sec;
315 out->st_ctim.tv_nsec = in->stx_ctime.tv_nsec;
316 }
317 # endif
318
319 # if SANITIZER_MIPS64
320 // Undefine compatibility macros from <sys/stat.h>
321 // so that they would not clash with the kernel_stat
322 // st_[a|m|c]time fields
323 # if !SANITIZER_GO
324 # undef st_atime
325 # undef st_mtime
326 # undef st_ctime
327 # endif
328 # if defined(SANITIZER_ANDROID)
329 // Bionic sys/stat.h defines additional macros
330 // for compatibility with the old NDKs and
331 // they clash with the kernel_stat structure
332 // st_[a|m|c]time_nsec fields.
333 # undef st_atime_nsec
334 # undef st_mtime_nsec
335 # undef st_ctime_nsec
336 # endif
kernel_stat_to_stat(struct kernel_stat * in,struct stat * out)337 static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) {
338 internal_memset(out, 0, sizeof(*out));
339 out->st_dev = in->st_dev;
340 out->st_ino = in->st_ino;
341 out->st_mode = in->st_mode;
342 out->st_nlink = in->st_nlink;
343 out->st_uid = in->st_uid;
344 out->st_gid = in->st_gid;
345 out->st_rdev = in->st_rdev;
346 out->st_size = in->st_size;
347 out->st_blksize = in->st_blksize;
348 out->st_blocks = in->st_blocks;
349 # if defined(__USE_MISC) || defined(__USE_XOPEN2K8) || \
350 defined(SANITIZER_ANDROID)
351 out->st_atim.tv_sec = in->st_atime;
352 out->st_atim.tv_nsec = in->st_atime_nsec;
353 out->st_mtim.tv_sec = in->st_mtime;
354 out->st_mtim.tv_nsec = in->st_mtime_nsec;
355 out->st_ctim.tv_sec = in->st_ctime;
356 out->st_ctim.tv_nsec = in->st_ctime_nsec;
357 # else
358 out->st_atime = in->st_atime;
359 out->st_atimensec = in->st_atime_nsec;
360 out->st_mtime = in->st_mtime;
361 out->st_mtimensec = in->st_mtime_nsec;
362 out->st_ctime = in->st_ctime;
363 out->st_atimensec = in->st_ctime_nsec;
364 # endif
365 }
366 # endif
367
internal_stat(const char * path,void * buf)368 uptr internal_stat(const char *path, void *buf) {
369 # if SANITIZER_FREEBSD
370 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf, 0);
371 # elif SANITIZER_LINUX
372 # if defined(__loongarch__)
373 struct statx bufx;
374 int res = internal_syscall(SYSCALL(statx), AT_FDCWD, (uptr)path,
375 AT_NO_AUTOMOUNT, STATX_BASIC_STATS, (uptr)&bufx);
376 statx_to_stat(&bufx, (struct stat *)buf);
377 return res;
378 # elif (SANITIZER_WORDSIZE == 64 || SANITIZER_X32 || \
379 (defined(__mips__) && _MIPS_SIM == _ABIN32)) && \
380 !SANITIZER_SPARC
381 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf,
382 0);
383 # else
384 struct stat64 buf64;
385 int res = internal_syscall(SYSCALL(fstatat64), AT_FDCWD, (uptr)path,
386 (uptr)&buf64, 0);
387 stat64_to_stat(&buf64, (struct stat *)buf);
388 return res;
389 # endif
390 # else
391 struct stat64 buf64;
392 int res = internal_syscall(SYSCALL(stat64), path, &buf64);
393 stat64_to_stat(&buf64, (struct stat *)buf);
394 return res;
395 # endif
396 }
397
internal_lstat(const char * path,void * buf)398 uptr internal_lstat(const char *path, void *buf) {
399 # if SANITIZER_FREEBSD
400 return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path, (uptr)buf,
401 AT_SYMLINK_NOFOLLOW);
402 # elif SANITIZER_LINUX
403 # if defined(__loongarch__)
404 struct statx bufx;
405 int res = internal_syscall(SYSCALL(statx), AT_FDCWD, (uptr)path,
406 AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT,
407 STATX_BASIC_STATS, (uptr)&bufx);
408 statx_to_stat(&bufx, (struct stat *)buf);
409 return res;
410 # elif (defined(_LP64) || SANITIZER_X32 || \
411 (defined(__mips__) && _MIPS_SIM == _ABIN32)) && \
412 !SANITIZER_SPARC
413 return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path, (uptr)buf,
414 AT_SYMLINK_NOFOLLOW);
415 # else
416 struct stat64 buf64;
417 int res = internal_syscall(SYSCALL(fstatat64), AT_FDCWD, (uptr)path,
418 (uptr)&buf64, AT_SYMLINK_NOFOLLOW);
419 stat64_to_stat(&buf64, (struct stat *)buf);
420 return res;
421 # endif
422 # else
423 struct stat64 buf64;
424 int res = internal_syscall(SYSCALL(lstat64), path, &buf64);
425 stat64_to_stat(&buf64, (struct stat *)buf);
426 return res;
427 # endif
428 }
429
internal_fstat(fd_t fd,void * buf)430 uptr internal_fstat(fd_t fd, void *buf) {
431 # if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS
432 # if SANITIZER_MIPS64
433 // For mips64, fstat syscall fills buffer in the format of kernel_stat
434 struct kernel_stat kbuf;
435 int res = internal_syscall(SYSCALL(fstat), fd, &kbuf);
436 kernel_stat_to_stat(&kbuf, (struct stat *)buf);
437 return res;
438 # elif SANITIZER_LINUX && defined(__loongarch__)
439 struct statx bufx;
440 int res = internal_syscall(SYSCALL(statx), fd, "", AT_EMPTY_PATH,
441 STATX_BASIC_STATS, (uptr)&bufx);
442 statx_to_stat(&bufx, (struct stat *)buf);
443 return res;
444 # else
445 return internal_syscall(SYSCALL(fstat), fd, (uptr)buf);
446 # endif
447 # else
448 struct stat64 buf64;
449 int res = internal_syscall(SYSCALL(fstat64), fd, &buf64);
450 stat64_to_stat(&buf64, (struct stat *)buf);
451 return res;
452 # endif
453 }
454
internal_filesize(fd_t fd)455 uptr internal_filesize(fd_t fd) {
456 struct stat st;
457 if (internal_fstat(fd, &st))
458 return -1;
459 return (uptr)st.st_size;
460 }
461
internal_dup(int oldfd)462 uptr internal_dup(int oldfd) { return internal_syscall(SYSCALL(dup), oldfd); }
463
internal_dup2(int oldfd,int newfd)464 uptr internal_dup2(int oldfd, int newfd) {
465 # if SANITIZER_LINUX
466 return internal_syscall(SYSCALL(dup3), oldfd, newfd, 0);
467 # else
468 return internal_syscall(SYSCALL(dup2), oldfd, newfd);
469 # endif
470 }
471
internal_readlink(const char * path,char * buf,uptr bufsize)472 uptr internal_readlink(const char *path, char *buf, uptr bufsize) {
473 # if SANITIZER_LINUX
474 return internal_syscall(SYSCALL(readlinkat), AT_FDCWD, (uptr)path, (uptr)buf,
475 bufsize);
476 # else
477 return internal_syscall(SYSCALL(readlink), (uptr)path, (uptr)buf, bufsize);
478 # endif
479 }
480
internal_unlink(const char * path)481 uptr internal_unlink(const char *path) {
482 # if SANITIZER_LINUX
483 return internal_syscall(SYSCALL(unlinkat), AT_FDCWD, (uptr)path, 0);
484 # else
485 return internal_syscall(SYSCALL(unlink), (uptr)path);
486 # endif
487 }
488
internal_rename(const char * oldpath,const char * newpath)489 uptr internal_rename(const char *oldpath, const char *newpath) {
490 # if (defined(__riscv) || defined(__loongarch__)) && defined(__linux__)
491 return internal_syscall(SYSCALL(renameat2), AT_FDCWD, (uptr)oldpath, AT_FDCWD,
492 (uptr)newpath, 0);
493 # elif SANITIZER_LINUX
494 return internal_syscall(SYSCALL(renameat), AT_FDCWD, (uptr)oldpath, AT_FDCWD,
495 (uptr)newpath);
496 # else
497 return internal_syscall(SYSCALL(rename), (uptr)oldpath, (uptr)newpath);
498 # endif
499 }
500
internal_sched_yield()501 uptr internal_sched_yield() { return internal_syscall(SYSCALL(sched_yield)); }
502
internal_usleep(u64 useconds)503 void internal_usleep(u64 useconds) {
504 struct timespec ts;
505 ts.tv_sec = useconds / 1000000;
506 ts.tv_nsec = (useconds % 1000000) * 1000;
507 internal_syscall(SYSCALL(nanosleep), &ts, &ts);
508 }
509
internal_execve(const char * filename,char * const argv[],char * const envp[])510 uptr internal_execve(const char *filename, char *const argv[],
511 char *const envp[]) {
512 return internal_syscall(SYSCALL(execve), (uptr)filename, (uptr)argv,
513 (uptr)envp);
514 }
515 # endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD
516
517 # if !SANITIZER_NETBSD
internal__exit(int exitcode)518 void internal__exit(int exitcode) {
519 # if SANITIZER_FREEBSD || SANITIZER_SOLARIS
520 internal_syscall(SYSCALL(exit), exitcode);
521 # else
522 internal_syscall(SYSCALL(exit_group), exitcode);
523 # endif
524 Die(); // Unreachable.
525 }
526 # endif // !SANITIZER_NETBSD
527
528 // ----------------- sanitizer_common.h
FileExists(const char * filename)529 bool FileExists(const char *filename) {
530 if (ShouldMockFailureToOpen(filename))
531 return false;
532 struct stat st;
533 if (internal_stat(filename, &st))
534 return false;
535 // Sanity check: filename is a regular file.
536 return S_ISREG(st.st_mode);
537 }
538
DirExists(const char * path)539 bool DirExists(const char *path) {
540 struct stat st;
541 if (internal_stat(path, &st))
542 return false;
543 return S_ISDIR(st.st_mode);
544 }
545
546 # if !SANITIZER_NETBSD
GetTid()547 tid_t GetTid() {
548 # if SANITIZER_FREEBSD
549 long Tid;
550 thr_self(&Tid);
551 return Tid;
552 # elif SANITIZER_SOLARIS
553 return thr_self();
554 # else
555 return internal_syscall(SYSCALL(gettid));
556 # endif
557 }
558
TgKill(pid_t pid,tid_t tid,int sig)559 int TgKill(pid_t pid, tid_t tid, int sig) {
560 # if SANITIZER_LINUX
561 return internal_syscall(SYSCALL(tgkill), pid, tid, sig);
562 # elif SANITIZER_FREEBSD
563 return internal_syscall(SYSCALL(thr_kill2), pid, tid, sig);
564 # elif SANITIZER_SOLARIS
565 (void)pid;
566 return thr_kill(tid, sig);
567 # endif
568 }
569 # endif
570
571 # if SANITIZER_GLIBC
NanoTime()572 u64 NanoTime() {
573 kernel_timeval tv;
574 internal_memset(&tv, 0, sizeof(tv));
575 internal_syscall(SYSCALL(gettimeofday), &tv, 0);
576 return (u64)tv.tv_sec * 1000 * 1000 * 1000 + tv.tv_usec * 1000;
577 }
578 // Used by real_clock_gettime.
internal_clock_gettime(__sanitizer_clockid_t clk_id,void * tp)579 uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) {
580 return internal_syscall(SYSCALL(clock_gettime), clk_id, tp);
581 }
582 # elif !SANITIZER_SOLARIS && !SANITIZER_NETBSD
NanoTime()583 u64 NanoTime() {
584 struct timespec ts;
585 clock_gettime(CLOCK_REALTIME, &ts);
586 return (u64)ts.tv_sec * 1000 * 1000 * 1000 + ts.tv_nsec;
587 }
588 # endif
589
590 // Like getenv, but reads env directly from /proc (on Linux) or parses the
591 // 'environ' array (on some others) and does not use libc. This function
592 // should be called first inside __asan_init.
GetEnv(const char * name)593 const char *GetEnv(const char *name) {
594 # if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_SOLARIS
595 if (::environ != 0) {
596 uptr NameLen = internal_strlen(name);
597 for (char **Env = ::environ; *Env != 0; Env++) {
598 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=')
599 return (*Env) + NameLen + 1;
600 }
601 }
602 return 0; // Not found.
603 # elif SANITIZER_LINUX
604 static char *environ;
605 static uptr len;
606 static bool inited;
607 if (!inited) {
608 inited = true;
609 uptr environ_size;
610 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len))
611 environ = nullptr;
612 }
613 if (!environ || len == 0)
614 return nullptr;
615 uptr namelen = internal_strlen(name);
616 const char *p = environ;
617 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer
618 // proc file has the format NAME=value\0NAME=value\0NAME=value\0...
619 const char *endp = (char *)internal_memchr(p, '\0', len - (p - environ));
620 if (!endp) // this entry isn't NUL terminated
621 return nullptr;
622 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match.
623 return p + namelen + 1; // point after =
624 p = endp + 1;
625 }
626 return nullptr; // Not found.
627 # else
628 # error "Unsupported platform"
629 # endif
630 }
631
632 # if !SANITIZER_FREEBSD && !SANITIZER_NETBSD && !SANITIZER_GO
633 extern "C" {
634 SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end;
635 }
636 # endif
637
638 # if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
ReadNullSepFileToArray(const char * path,char *** arr,int arr_size)639 static void ReadNullSepFileToArray(const char *path, char ***arr,
640 int arr_size) {
641 char *buff;
642 uptr buff_size;
643 uptr buff_len;
644 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray");
645 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) {
646 (*arr)[0] = nullptr;
647 return;
648 }
649 (*arr)[0] = buff;
650 int count, i;
651 for (count = 1, i = 1;; i++) {
652 if (buff[i] == 0) {
653 if (buff[i + 1] == 0)
654 break;
655 (*arr)[count] = &buff[i + 1];
656 CHECK_LE(count, arr_size - 1); // FIXME: make this more flexible.
657 count++;
658 }
659 }
660 (*arr)[count] = nullptr;
661 }
662 # endif
663
GetArgsAndEnv(char *** argv,char *** envp)664 static void GetArgsAndEnv(char ***argv, char ***envp) {
665 # if SANITIZER_FREEBSD
666 // On FreeBSD, retrieving the argument and environment arrays is done via the
667 // kern.ps_strings sysctl, which returns a pointer to a structure containing
668 // this information. See also <sys/exec.h>.
669 ps_strings *pss;
670 uptr sz = sizeof(pss);
671 if (internal_sysctlbyname("kern.ps_strings", &pss, &sz, NULL, 0) == -1) {
672 Printf("sysctl kern.ps_strings failed\n");
673 Die();
674 }
675 *argv = pss->ps_argvstr;
676 *envp = pss->ps_envstr;
677 # elif SANITIZER_NETBSD
678 *argv = __ps_strings->ps_argvstr;
679 *envp = __ps_strings->ps_envstr;
680 # else // SANITIZER_FREEBSD
681 # if !SANITIZER_GO
682 if (&__libc_stack_end) {
683 uptr *stack_end = (uptr *)__libc_stack_end;
684 // Normally argc can be obtained from *stack_end, however, on ARM glibc's
685 // _start clobbers it:
686 // https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/arm/start.S;hb=refs/heads/release/2.31/master#l75
687 // Do not special-case ARM and infer argc from argv everywhere.
688 int argc = 0;
689 while (stack_end[argc + 1]) argc++;
690 *argv = (char **)(stack_end + 1);
691 *envp = (char **)(stack_end + argc + 2);
692 } else {
693 # endif // !SANITIZER_GO
694 static const int kMaxArgv = 2000, kMaxEnvp = 2000;
695 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv);
696 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp);
697 # if !SANITIZER_GO
698 }
699 # endif // !SANITIZER_GO
700 # endif // SANITIZER_FREEBSD
701 }
702
GetArgv()703 char **GetArgv() {
704 char **argv, **envp;
705 GetArgsAndEnv(&argv, &envp);
706 return argv;
707 }
708
GetEnviron()709 char **GetEnviron() {
710 char **argv, **envp;
711 GetArgsAndEnv(&argv, &envp);
712 return envp;
713 }
714
715 # if !SANITIZER_SOLARIS
FutexWait(atomic_uint32_t * p,u32 cmp)716 void FutexWait(atomic_uint32_t *p, u32 cmp) {
717 # if SANITIZER_FREEBSD
718 _umtx_op(p, UMTX_OP_WAIT_UINT, cmp, 0, 0);
719 # elif SANITIZER_NETBSD
720 sched_yield(); /* No userspace futex-like synchronization */
721 # else
722 internal_syscall(SYSCALL(futex), (uptr)p, FUTEX_WAIT_PRIVATE, cmp, 0, 0, 0);
723 # endif
724 }
725
FutexWake(atomic_uint32_t * p,u32 count)726 void FutexWake(atomic_uint32_t *p, u32 count) {
727 # if SANITIZER_FREEBSD
728 _umtx_op(p, UMTX_OP_WAKE, count, 0, 0);
729 # elif SANITIZER_NETBSD
730 /* No userspace futex-like synchronization */
731 # else
732 internal_syscall(SYSCALL(futex), (uptr)p, FUTEX_WAKE_PRIVATE, count, 0, 0, 0);
733 # endif
734 }
735
736 # endif // !SANITIZER_SOLARIS
737
738 // ----------------- sanitizer_linux.h
739 // The actual size of this structure is specified by d_reclen.
740 // Note that getdents64 uses a different structure format. We only provide the
741 // 32-bit syscall here.
742 # if SANITIZER_NETBSD
743 // Not used
744 # else
745 struct linux_dirent {
746 # if SANITIZER_X32 || SANITIZER_LINUX
747 u64 d_ino;
748 u64 d_off;
749 # else
750 unsigned long d_ino;
751 unsigned long d_off;
752 # endif
753 unsigned short d_reclen;
754 # if SANITIZER_LINUX
755 unsigned char d_type;
756 # endif
757 char d_name[256];
758 };
759 # endif
760
761 # if !SANITIZER_SOLARIS && !SANITIZER_NETBSD
762 // Syscall wrappers.
internal_ptrace(int request,int pid,void * addr,void * data)763 uptr internal_ptrace(int request, int pid, void *addr, void *data) {
764 return internal_syscall(SYSCALL(ptrace), request, pid, (uptr)addr,
765 (uptr)data);
766 }
767
internal_waitpid(int pid,int * status,int options)768 uptr internal_waitpid(int pid, int *status, int options) {
769 return internal_syscall(SYSCALL(wait4), pid, (uptr)status, options,
770 0 /* rusage */);
771 }
772
internal_getpid()773 uptr internal_getpid() { return internal_syscall(SYSCALL(getpid)); }
774
internal_getppid()775 uptr internal_getppid() { return internal_syscall(SYSCALL(getppid)); }
776
internal_dlinfo(void * handle,int request,void * p)777 int internal_dlinfo(void *handle, int request, void *p) {
778 # if SANITIZER_FREEBSD
779 return dlinfo(handle, request, p);
780 # else
781 UNIMPLEMENTED();
782 # endif
783 }
784
internal_getdents(fd_t fd,struct linux_dirent * dirp,unsigned int count)785 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) {
786 # if SANITIZER_FREEBSD
787 return internal_syscall(SYSCALL(getdirentries), fd, (uptr)dirp, count, NULL);
788 # elif SANITIZER_LINUX
789 return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count);
790 # else
791 return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count);
792 # endif
793 }
794
internal_lseek(fd_t fd,OFF_T offset,int whence)795 uptr internal_lseek(fd_t fd, OFF_T offset, int whence) {
796 return internal_syscall(SYSCALL(lseek), fd, offset, whence);
797 }
798
799 # if SANITIZER_LINUX
internal_prctl(int option,uptr arg2,uptr arg3,uptr arg4,uptr arg5)800 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) {
801 return internal_syscall(SYSCALL(prctl), option, arg2, arg3, arg4, arg5);
802 }
803 # if defined(__x86_64__)
804 # include <asm/unistd_64.h>
805 // Currently internal_arch_prctl() is only needed on x86_64.
internal_arch_prctl(int option,uptr arg2)806 uptr internal_arch_prctl(int option, uptr arg2) {
807 return internal_syscall(__NR_arch_prctl, option, arg2);
808 }
809 # endif
810 # endif
811
internal_sigaltstack(const void * ss,void * oss)812 uptr internal_sigaltstack(const void *ss, void *oss) {
813 return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss);
814 }
815
internal_fork()816 int internal_fork() {
817 # if SANITIZER_LINUX
818 # if SANITIZER_S390
819 return internal_syscall(SYSCALL(clone), 0, SIGCHLD);
820 # else
821 return internal_syscall(SYSCALL(clone), SIGCHLD, 0);
822 # endif
823 # else
824 return internal_syscall(SYSCALL(fork));
825 # endif
826 }
827
828 # if SANITIZER_FREEBSD
internal_sysctl(const int * name,unsigned int namelen,void * oldp,uptr * oldlenp,const void * newp,uptr newlen)829 int internal_sysctl(const int *name, unsigned int namelen, void *oldp,
830 uptr *oldlenp, const void *newp, uptr newlen) {
831 return internal_syscall(SYSCALL(__sysctl), name, namelen, oldp,
832 (size_t *)oldlenp, newp, (size_t)newlen);
833 }
834
internal_sysctlbyname(const char * sname,void * oldp,uptr * oldlenp,const void * newp,uptr newlen)835 int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp,
836 const void *newp, uptr newlen) {
837 // Note: this function can be called during startup, so we need to avoid
838 // calling any interceptable functions. On FreeBSD >= 1300045 sysctlbyname()
839 // is a real syscall, but for older versions it calls sysctlnametomib()
840 // followed by sysctl(). To avoid calling the intercepted version and
841 // asserting if this happens during startup, call the real sysctlnametomib()
842 // followed by internal_sysctl() if the syscall is not available.
843 # ifdef SYS___sysctlbyname
844 return internal_syscall(SYSCALL(__sysctlbyname), sname,
845 internal_strlen(sname), oldp, (size_t *)oldlenp, newp,
846 (size_t)newlen);
847 # else
848 static decltype(sysctlnametomib) *real_sysctlnametomib = nullptr;
849 if (!real_sysctlnametomib)
850 real_sysctlnametomib =
851 (decltype(sysctlnametomib) *)dlsym(RTLD_NEXT, "sysctlnametomib");
852 CHECK(real_sysctlnametomib);
853
854 int oid[CTL_MAXNAME];
855 size_t len = CTL_MAXNAME;
856 if (real_sysctlnametomib(sname, oid, &len) == -1)
857 return (-1);
858 return internal_sysctl(oid, len, oldp, oldlenp, newp, newlen);
859 # endif
860 }
861 # endif
862
863 # if SANITIZER_LINUX
864 # define SA_RESTORER 0x04000000
865 // Doesn't set sa_restorer if the caller did not set it, so use with caution
866 //(see below).
internal_sigaction_norestorer(int signum,const void * act,void * oldact)867 int internal_sigaction_norestorer(int signum, const void *act, void *oldact) {
868 __sanitizer_kernel_sigaction_t k_act, k_oldact;
869 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t));
870 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t));
871 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act;
872 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact;
873 if (u_act) {
874 k_act.handler = u_act->handler;
875 k_act.sigaction = u_act->sigaction;
876 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask,
877 sizeof(__sanitizer_kernel_sigset_t));
878 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL).
879 k_act.sa_flags = u_act->sa_flags | SA_RESTORER;
880 // FIXME: most often sa_restorer is unset, however the kernel requires it
881 // to point to a valid signal restorer that calls the rt_sigreturn syscall.
882 // If sa_restorer passed to the kernel is NULL, the program may crash upon
883 // signal delivery or fail to unwind the stack in the signal handler.
884 // libc implementation of sigaction() passes its own restorer to
885 // rt_sigaction, so we need to do the same (we'll need to reimplement the
886 // restorers; for x86_64 the restorer address can be obtained from
887 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact).
888 # if !SANITIZER_ANDROID || !SANITIZER_MIPS32
889 k_act.sa_restorer = u_act->sa_restorer;
890 # endif
891 }
892
893 uptr result = internal_syscall(SYSCALL(rt_sigaction), (uptr)signum,
894 (uptr)(u_act ? &k_act : nullptr),
895 (uptr)(u_oldact ? &k_oldact : nullptr),
896 (uptr)sizeof(__sanitizer_kernel_sigset_t));
897
898 if ((result == 0) && u_oldact) {
899 u_oldact->handler = k_oldact.handler;
900 u_oldact->sigaction = k_oldact.sigaction;
901 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask,
902 sizeof(__sanitizer_kernel_sigset_t));
903 u_oldact->sa_flags = k_oldact.sa_flags;
904 # if !SANITIZER_ANDROID || !SANITIZER_MIPS32
905 u_oldact->sa_restorer = k_oldact.sa_restorer;
906 # endif
907 }
908 return result;
909 }
910 # endif // SANITIZER_LINUX
911
internal_sigprocmask(int how,__sanitizer_sigset_t * set,__sanitizer_sigset_t * oldset)912 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
913 __sanitizer_sigset_t *oldset) {
914 # if SANITIZER_FREEBSD
915 return internal_syscall(SYSCALL(sigprocmask), how, set, oldset);
916 # else
917 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set;
918 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset;
919 return internal_syscall(SYSCALL(rt_sigprocmask), (uptr)how, (uptr)k_set,
920 (uptr)k_oldset, sizeof(__sanitizer_kernel_sigset_t));
921 # endif
922 }
923
internal_sigfillset(__sanitizer_sigset_t * set)924 void internal_sigfillset(__sanitizer_sigset_t *set) {
925 internal_memset(set, 0xff, sizeof(*set));
926 }
927
internal_sigemptyset(__sanitizer_sigset_t * set)928 void internal_sigemptyset(__sanitizer_sigset_t *set) {
929 internal_memset(set, 0, sizeof(*set));
930 }
931
932 # if SANITIZER_LINUX
internal_sigdelset(__sanitizer_sigset_t * set,int signum)933 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) {
934 signum -= 1;
935 CHECK_GE(signum, 0);
936 CHECK_LT(signum, sizeof(*set) * 8);
937 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set;
938 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8);
939 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8);
940 k_set->sig[idx] &= ~((uptr)1 << bit);
941 }
942
internal_sigismember(__sanitizer_sigset_t * set,int signum)943 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) {
944 signum -= 1;
945 CHECK_GE(signum, 0);
946 CHECK_LT(signum, sizeof(*set) * 8);
947 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set;
948 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8);
949 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8);
950 return k_set->sig[idx] & ((uptr)1 << bit);
951 }
952 # elif SANITIZER_FREEBSD
internal_procctl(int type,int id,int cmd,void * data)953 uptr internal_procctl(int type, int id, int cmd, void *data) {
954 return internal_syscall(SYSCALL(procctl), type, id, cmd, data);
955 }
956
internal_sigdelset(__sanitizer_sigset_t * set,int signum)957 void internal_sigdelset(__sanitizer_sigset_t *set, int signum) {
958 sigset_t *rset = reinterpret_cast<sigset_t *>(set);
959 sigdelset(rset, signum);
960 }
961
internal_sigismember(__sanitizer_sigset_t * set,int signum)962 bool internal_sigismember(__sanitizer_sigset_t *set, int signum) {
963 sigset_t *rset = reinterpret_cast<sigset_t *>(set);
964 return sigismember(rset, signum);
965 }
966 # endif
967 # endif // !SANITIZER_SOLARIS
968
969 # if !SANITIZER_NETBSD
970 // ThreadLister implementation.
ThreadLister(pid_t pid)971 ThreadLister::ThreadLister(pid_t pid) : pid_(pid), buffer_(4096) {
972 char task_directory_path[80];
973 internal_snprintf(task_directory_path, sizeof(task_directory_path),
974 "/proc/%d/task/", pid);
975 descriptor_ = internal_open(task_directory_path, O_RDONLY | O_DIRECTORY);
976 if (internal_iserror(descriptor_)) {
977 Report("Can't open /proc/%d/task for reading.\n", pid);
978 }
979 }
980
ListThreads(InternalMmapVector<tid_t> * threads)981 ThreadLister::Result ThreadLister::ListThreads(
982 InternalMmapVector<tid_t> *threads) {
983 if (internal_iserror(descriptor_))
984 return Error;
985 internal_lseek(descriptor_, 0, SEEK_SET);
986 threads->clear();
987
988 Result result = Ok;
989 for (bool first_read = true;; first_read = false) {
990 // Resize to max capacity if it was downsized by IsAlive.
991 buffer_.resize(buffer_.capacity());
992 CHECK_GE(buffer_.size(), 4096);
993 uptr read = internal_getdents(
994 descriptor_, (struct linux_dirent *)buffer_.data(), buffer_.size());
995 if (!read)
996 return result;
997 if (internal_iserror(read)) {
998 Report("Can't read directory entries from /proc/%d/task.\n", pid_);
999 return Error;
1000 }
1001
1002 for (uptr begin = (uptr)buffer_.data(), end = begin + read; begin < end;) {
1003 struct linux_dirent *entry = (struct linux_dirent *)begin;
1004 begin += entry->d_reclen;
1005 if (entry->d_ino == 1) {
1006 // Inode 1 is for bad blocks and also can be a reason for early return.
1007 // Should be emitted if kernel tried to output terminating thread.
1008 // See proc_task_readdir implementation in Linux.
1009 result = Incomplete;
1010 }
1011 if (entry->d_ino && *entry->d_name >= '0' && *entry->d_name <= '9')
1012 threads->push_back(internal_atoll(entry->d_name));
1013 }
1014
1015 // Now we are going to detect short-read or early EOF. In such cases Linux
1016 // can return inconsistent list with missing alive threads.
1017 // Code will just remember that the list can be incomplete but it will
1018 // continue reads to return as much as possible.
1019 if (!first_read) {
1020 // The first one was a short-read by definition.
1021 result = Incomplete;
1022 } else if (read > buffer_.size() - 1024) {
1023 // Read was close to the buffer size. So double the size and assume the
1024 // worst.
1025 buffer_.resize(buffer_.size() * 2);
1026 result = Incomplete;
1027 } else if (!threads->empty() && !IsAlive(threads->back())) {
1028 // Maybe Linux early returned from read on terminated thread (!pid_alive)
1029 // and failed to restore read position.
1030 // See next_tid and proc_task_instantiate in Linux.
1031 result = Incomplete;
1032 }
1033 }
1034 }
1035
IsAlive(int tid)1036 bool ThreadLister::IsAlive(int tid) {
1037 // /proc/%d/task/%d/status uses same call to detect alive threads as
1038 // proc_task_readdir. See task_state implementation in Linux.
1039 char path[80];
1040 internal_snprintf(path, sizeof(path), "/proc/%d/task/%d/status", pid_, tid);
1041 if (!ReadFileToVector(path, &buffer_) || buffer_.empty())
1042 return false;
1043 buffer_.push_back(0);
1044 static const char kPrefix[] = "\nPPid:";
1045 const char *field = internal_strstr(buffer_.data(), kPrefix);
1046 if (!field)
1047 return false;
1048 field += internal_strlen(kPrefix);
1049 return (int)internal_atoll(field) != 0;
1050 }
1051
~ThreadLister()1052 ThreadLister::~ThreadLister() {
1053 if (!internal_iserror(descriptor_))
1054 internal_close(descriptor_);
1055 }
1056 # endif
1057
1058 # if SANITIZER_WORDSIZE == 32
1059 // Take care of unusable kernel area in top gigabyte.
GetKernelAreaSize()1060 static uptr GetKernelAreaSize() {
1061 # if SANITIZER_LINUX && !SANITIZER_X32
1062 const uptr gbyte = 1UL << 30;
1063
1064 // Firstly check if there are writable segments
1065 // mapped to top gigabyte (e.g. stack).
1066 MemoryMappingLayout proc_maps(/*cache_enabled*/ true);
1067 if (proc_maps.Error())
1068 return 0;
1069 MemoryMappedSegment segment;
1070 while (proc_maps.Next(&segment)) {
1071 if ((segment.end >= 3 * gbyte) && segment.IsWritable())
1072 return 0;
1073 }
1074
1075 # if !SANITIZER_ANDROID
1076 // Even if nothing is mapped, top Gb may still be accessible
1077 // if we are running on 64-bit kernel.
1078 // Uname may report misleading results if personality type
1079 // is modified (e.g. under schroot) so check this as well.
1080 struct utsname uname_info;
1081 int pers = personality(0xffffffffUL);
1082 if (!(pers & PER_MASK) && internal_uname(&uname_info) == 0 &&
1083 internal_strstr(uname_info.machine, "64"))
1084 return 0;
1085 # endif // SANITIZER_ANDROID
1086
1087 // Top gigabyte is reserved for kernel.
1088 return gbyte;
1089 # else
1090 return 0;
1091 # endif // SANITIZER_LINUX && !SANITIZER_X32
1092 }
1093 # endif // SANITIZER_WORDSIZE == 32
1094
GetMaxVirtualAddress()1095 uptr GetMaxVirtualAddress() {
1096 # if SANITIZER_NETBSD && defined(__x86_64__)
1097 return 0x7f7ffffff000ULL; // (0x00007f8000000000 - PAGE_SIZE)
1098 # elif SANITIZER_WORDSIZE == 64
1099 # if defined(__powerpc64__) || defined(__aarch64__) || defined(__loongarch__)
1100 // On PowerPC64 we have two different address space layouts: 44- and 46-bit.
1101 // We somehow need to figure out which one we are using now and choose
1102 // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL.
1103 // Note that with 'ulimit -s unlimited' the stack is moved away from the top
1104 // of the address space, so simply checking the stack address is not enough.
1105 // This should (does) work for both PowerPC64 Endian modes.
1106 // Similarly, aarch64 has multiple address space layouts: 39, 42 and 47-bit.
1107 // loongarch64 also has multiple address space layouts: default is 47-bit.
1108 return (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1)) - 1;
1109 # elif SANITIZER_RISCV64
1110 return (1ULL << 38) - 1;
1111 # elif SANITIZER_MIPS64
1112 return (1ULL << 40) - 1; // 0x000000ffffffffffUL;
1113 # elif defined(__s390x__)
1114 return (1ULL << 53) - 1; // 0x001fffffffffffffUL;
1115 # elif defined(__sparc__)
1116 return ~(uptr)0;
1117 # else
1118 return (1ULL << 47) - 1; // 0x00007fffffffffffUL;
1119 # endif
1120 # else // SANITIZER_WORDSIZE == 32
1121 # if defined(__s390__)
1122 return (1ULL << 31) - 1; // 0x7fffffff;
1123 # else
1124 return (1ULL << 32) - 1; // 0xffffffff;
1125 # endif
1126 # endif // SANITIZER_WORDSIZE
1127 }
1128
GetMaxUserVirtualAddress()1129 uptr GetMaxUserVirtualAddress() {
1130 uptr addr = GetMaxVirtualAddress();
1131 # if SANITIZER_WORDSIZE == 32 && !defined(__s390__)
1132 if (!common_flags()->full_address_space)
1133 addr -= GetKernelAreaSize();
1134 CHECK_LT(reinterpret_cast<uptr>(&addr), addr);
1135 # endif
1136 return addr;
1137 }
1138
1139 # if !SANITIZER_ANDROID
GetPageSize()1140 uptr GetPageSize() {
1141 # if SANITIZER_LINUX && (defined(__x86_64__) || defined(__i386__)) && \
1142 defined(EXEC_PAGESIZE)
1143 return EXEC_PAGESIZE;
1144 # elif SANITIZER_FREEBSD || SANITIZER_NETBSD
1145 // Use sysctl as sysconf can trigger interceptors internally.
1146 int pz = 0;
1147 uptr pzl = sizeof(pz);
1148 int mib[2] = {CTL_HW, HW_PAGESIZE};
1149 int rv = internal_sysctl(mib, 2, &pz, &pzl, nullptr, 0);
1150 CHECK_EQ(rv, 0);
1151 return (uptr)pz;
1152 # elif SANITIZER_USE_GETAUXVAL
1153 return getauxval(AT_PAGESZ);
1154 # else
1155 return sysconf(_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy.
1156 # endif
1157 }
1158 # endif // !SANITIZER_ANDROID
1159
ReadBinaryName(char * buf,uptr buf_len)1160 uptr ReadBinaryName(/*out*/ char *buf, uptr buf_len) {
1161 # if SANITIZER_SOLARIS
1162 const char *default_module_name = getexecname();
1163 CHECK_NE(default_module_name, NULL);
1164 return internal_snprintf(buf, buf_len, "%s", default_module_name);
1165 # else
1166 # if SANITIZER_FREEBSD || SANITIZER_NETBSD
1167 # if SANITIZER_FREEBSD
1168 const int Mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1};
1169 # else
1170 const int Mib[4] = {CTL_KERN, KERN_PROC_ARGS, -1, KERN_PROC_PATHNAME};
1171 # endif
1172 const char *default_module_name = "kern.proc.pathname";
1173 uptr Size = buf_len;
1174 bool IsErr =
1175 (internal_sysctl(Mib, ARRAY_SIZE(Mib), buf, &Size, NULL, 0) != 0);
1176 int readlink_error = IsErr ? errno : 0;
1177 uptr module_name_len = Size;
1178 # else
1179 const char *default_module_name = "/proc/self/exe";
1180 uptr module_name_len = internal_readlink(default_module_name, buf, buf_len);
1181 int readlink_error;
1182 bool IsErr = internal_iserror(module_name_len, &readlink_error);
1183 # endif // SANITIZER_SOLARIS
1184 if (IsErr) {
1185 // We can't read binary name for some reason, assume it's unknown.
1186 Report(
1187 "WARNING: reading executable name failed with errno %d, "
1188 "some stack frames may not be symbolized\n",
1189 readlink_error);
1190 module_name_len =
1191 internal_snprintf(buf, buf_len, "%s", default_module_name);
1192 CHECK_LT(module_name_len, buf_len);
1193 }
1194 return module_name_len;
1195 # endif
1196 }
1197
ReadLongProcessName(char * buf,uptr buf_len)1198 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) {
1199 # if SANITIZER_LINUX
1200 char *tmpbuf;
1201 uptr tmpsize;
1202 uptr tmplen;
1203 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen,
1204 1024 * 1024)) {
1205 internal_strncpy(buf, tmpbuf, buf_len);
1206 UnmapOrDie(tmpbuf, tmpsize);
1207 return internal_strlen(buf);
1208 }
1209 # endif
1210 return ReadBinaryName(buf, buf_len);
1211 }
1212
1213 // Match full names of the form /path/to/base_name{-,.}*
LibraryNameIs(const char * full_name,const char * base_name)1214 bool LibraryNameIs(const char *full_name, const char *base_name) {
1215 const char *name = full_name;
1216 // Strip path.
1217 while (*name != '\0') name++;
1218 while (name > full_name && *name != '/') name--;
1219 if (*name == '/')
1220 name++;
1221 uptr base_name_length = internal_strlen(base_name);
1222 if (internal_strncmp(name, base_name, base_name_length))
1223 return false;
1224 return (name[base_name_length] == '-' || name[base_name_length] == '.');
1225 }
1226
1227 # if !SANITIZER_ANDROID
1228 // Call cb for each region mapped by map.
ForEachMappedRegion(link_map * map,void (* cb)(const void *,uptr))1229 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) {
1230 CHECK_NE(map, nullptr);
1231 # if !SANITIZER_FREEBSD
1232 typedef ElfW(Phdr) Elf_Phdr;
1233 typedef ElfW(Ehdr) Elf_Ehdr;
1234 # endif // !SANITIZER_FREEBSD
1235 char *base = (char *)map->l_addr;
1236 Elf_Ehdr *ehdr = (Elf_Ehdr *)base;
1237 char *phdrs = base + ehdr->e_phoff;
1238 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize;
1239
1240 // Find the segment with the minimum base so we can "relocate" the p_vaddr
1241 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC
1242 // objects have a non-zero base.
1243 uptr preferred_base = (uptr)-1;
1244 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) {
1245 Elf_Phdr *phdr = (Elf_Phdr *)iter;
1246 if (phdr->p_type == PT_LOAD && preferred_base > (uptr)phdr->p_vaddr)
1247 preferred_base = (uptr)phdr->p_vaddr;
1248 }
1249
1250 // Compute the delta from the real base to get a relocation delta.
1251 sptr delta = (uptr)base - preferred_base;
1252 // Now we can figure out what the loader really mapped.
1253 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) {
1254 Elf_Phdr *phdr = (Elf_Phdr *)iter;
1255 if (phdr->p_type == PT_LOAD) {
1256 uptr seg_start = phdr->p_vaddr + delta;
1257 uptr seg_end = seg_start + phdr->p_memsz;
1258 // None of these values are aligned. We consider the ragged edges of the
1259 // load command as defined, since they are mapped from the file.
1260 seg_start = RoundDownTo(seg_start, GetPageSizeCached());
1261 seg_end = RoundUpTo(seg_end, GetPageSizeCached());
1262 cb((void *)seg_start, seg_end - seg_start);
1263 }
1264 }
1265 }
1266 # endif
1267
1268 # if SANITIZER_LINUX
1269 # if defined(__x86_64__)
1270 // We cannot use glibc's clone wrapper, because it messes with the child
1271 // task's TLS. It writes the PID and TID of the child task to its thread
1272 // descriptor, but in our case the child task shares the thread descriptor with
1273 // the parent (because we don't know how to allocate a new thread
1274 // descriptor to keep glibc happy). So the stock version of clone(), when
1275 // used with CLONE_VM, would end up corrupting the parent's thread descriptor.
internal_clone(int (* fn)(void *),void * child_stack,int flags,void * arg,int * parent_tidptr,void * newtls,int * child_tidptr)1276 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1277 int *parent_tidptr, void *newtls, int *child_tidptr) {
1278 long long res;
1279 if (!fn || !child_stack)
1280 return -EINVAL;
1281 CHECK_EQ(0, (uptr)child_stack % 16);
1282 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
1283 ((unsigned long long *)child_stack)[0] = (uptr)fn;
1284 ((unsigned long long *)child_stack)[1] = (uptr)arg;
1285 register void *r8 __asm__("r8") = newtls;
1286 register int *r10 __asm__("r10") = child_tidptr;
1287 __asm__ __volatile__(
1288 /* %rax = syscall(%rax = SYSCALL(clone),
1289 * %rdi = flags,
1290 * %rsi = child_stack,
1291 * %rdx = parent_tidptr,
1292 * %r8 = new_tls,
1293 * %r10 = child_tidptr)
1294 */
1295 "syscall\n"
1296
1297 /* if (%rax != 0)
1298 * return;
1299 */
1300 "testq %%rax,%%rax\n"
1301 "jnz 1f\n"
1302
1303 /* In the child. Terminate unwind chain. */
1304 // XXX: We should also terminate the CFI unwind chain
1305 // here. Unfortunately clang 3.2 doesn't support the
1306 // necessary CFI directives, so we skip that part.
1307 "xorq %%rbp,%%rbp\n"
1308
1309 /* Call "fn(arg)". */
1310 "popq %%rax\n"
1311 "popq %%rdi\n"
1312 "call *%%rax\n"
1313
1314 /* Call _exit(%rax). */
1315 "movq %%rax,%%rdi\n"
1316 "movq %2,%%rax\n"
1317 "syscall\n"
1318
1319 /* Return to parent. */
1320 "1:\n"
1321 : "=a"(res)
1322 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), "S"(child_stack), "D"(flags),
1323 "d"(parent_tidptr), "r"(r8), "r"(r10)
1324 : "memory", "r11", "rcx");
1325 return res;
1326 }
1327 # elif defined(__mips__)
internal_clone(int (* fn)(void *),void * child_stack,int flags,void * arg,int * parent_tidptr,void * newtls,int * child_tidptr)1328 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1329 int *parent_tidptr, void *newtls, int *child_tidptr) {
1330 long long res;
1331 if (!fn || !child_stack)
1332 return -EINVAL;
1333 CHECK_EQ(0, (uptr)child_stack % 16);
1334 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
1335 ((unsigned long long *)child_stack)[0] = (uptr)fn;
1336 ((unsigned long long *)child_stack)[1] = (uptr)arg;
1337 register void *a3 __asm__("$7") = newtls;
1338 register int *a4 __asm__("$8") = child_tidptr;
1339 // We don't have proper CFI directives here because it requires alot of code
1340 // for very marginal benefits.
1341 __asm__ __volatile__(
1342 /* $v0 = syscall($v0 = __NR_clone,
1343 * $a0 = flags,
1344 * $a1 = child_stack,
1345 * $a2 = parent_tidptr,
1346 * $a3 = new_tls,
1347 * $a4 = child_tidptr)
1348 */
1349 ".cprestore 16;\n"
1350 "move $4,%1;\n"
1351 "move $5,%2;\n"
1352 "move $6,%3;\n"
1353 "move $7,%4;\n"
1354 /* Store the fifth argument on stack
1355 * if we are using 32-bit abi.
1356 */
1357 # if SANITIZER_WORDSIZE == 32
1358 "lw %5,16($29);\n"
1359 # else
1360 "move $8,%5;\n"
1361 # endif
1362 "li $2,%6;\n"
1363 "syscall;\n"
1364
1365 /* if ($v0 != 0)
1366 * return;
1367 */
1368 "bnez $2,1f;\n"
1369
1370 /* Call "fn(arg)". */
1371 # if SANITIZER_WORDSIZE == 32
1372 # ifdef __BIG_ENDIAN__
1373 "lw $25,4($29);\n"
1374 "lw $4,12($29);\n"
1375 # else
1376 "lw $25,0($29);\n"
1377 "lw $4,8($29);\n"
1378 # endif
1379 # else
1380 "ld $25,0($29);\n"
1381 "ld $4,8($29);\n"
1382 # endif
1383 "jal $25;\n"
1384
1385 /* Call _exit($v0). */
1386 "move $4,$2;\n"
1387 "li $2,%7;\n"
1388 "syscall;\n"
1389
1390 /* Return to parent. */
1391 "1:\n"
1392 : "=r"(res)
1393 : "r"(flags), "r"(child_stack), "r"(parent_tidptr), "r"(a3), "r"(a4),
1394 "i"(__NR_clone), "i"(__NR_exit)
1395 : "memory", "$29");
1396 return res;
1397 }
1398 # elif SANITIZER_RISCV64
internal_clone(int (* fn)(void *),void * child_stack,int flags,void * arg,int * parent_tidptr,void * newtls,int * child_tidptr)1399 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1400 int *parent_tidptr, void *newtls, int *child_tidptr) {
1401 if (!fn || !child_stack)
1402 return -EINVAL;
1403
1404 CHECK_EQ(0, (uptr)child_stack % 16);
1405
1406 register int res __asm__("a0");
1407 register int __flags __asm__("a0") = flags;
1408 register void *__stack __asm__("a1") = child_stack;
1409 register int *__ptid __asm__("a2") = parent_tidptr;
1410 register void *__tls __asm__("a3") = newtls;
1411 register int *__ctid __asm__("a4") = child_tidptr;
1412 register int (*__fn)(void *) __asm__("a5") = fn;
1413 register void *__arg __asm__("a6") = arg;
1414 register int nr_clone __asm__("a7") = __NR_clone;
1415
1416 __asm__ __volatile__(
1417 "ecall\n"
1418
1419 /* if (a0 != 0)
1420 * return a0;
1421 */
1422 "bnez a0, 1f\n"
1423
1424 // In the child, now. Call "fn(arg)".
1425 "mv a0, a6\n"
1426 "jalr a5\n"
1427
1428 // Call _exit(a0).
1429 "addi a7, zero, %9\n"
1430 "ecall\n"
1431 "1:\n"
1432
1433 : "=r"(res)
1434 : "0"(__flags), "r"(__stack), "r"(__ptid), "r"(__tls), "r"(__ctid),
1435 "r"(__fn), "r"(__arg), "r"(nr_clone), "i"(__NR_exit)
1436 : "memory");
1437 return res;
1438 }
1439 # elif defined(__aarch64__)
internal_clone(int (* fn)(void *),void * child_stack,int flags,void * arg,int * parent_tidptr,void * newtls,int * child_tidptr)1440 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1441 int *parent_tidptr, void *newtls, int *child_tidptr) {
1442 register long long res __asm__("x0");
1443 if (!fn || !child_stack)
1444 return -EINVAL;
1445 CHECK_EQ(0, (uptr)child_stack % 16);
1446 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
1447 ((unsigned long long *)child_stack)[0] = (uptr)fn;
1448 ((unsigned long long *)child_stack)[1] = (uptr)arg;
1449
1450 register int (*__fn)(void *) __asm__("x0") = fn;
1451 register void *__stack __asm__("x1") = child_stack;
1452 register int __flags __asm__("x2") = flags;
1453 register void *__arg __asm__("x3") = arg;
1454 register int *__ptid __asm__("x4") = parent_tidptr;
1455 register void *__tls __asm__("x5") = newtls;
1456 register int *__ctid __asm__("x6") = child_tidptr;
1457
1458 __asm__ __volatile__(
1459 "mov x0,x2\n" /* flags */
1460 "mov x2,x4\n" /* ptid */
1461 "mov x3,x5\n" /* tls */
1462 "mov x4,x6\n" /* ctid */
1463 "mov x8,%9\n" /* clone */
1464
1465 "svc 0x0\n"
1466
1467 /* if (%r0 != 0)
1468 * return %r0;
1469 */
1470 "cmp x0, #0\n"
1471 "bne 1f\n"
1472
1473 /* In the child, now. Call "fn(arg)". */
1474 "ldp x1, x0, [sp], #16\n"
1475 "blr x1\n"
1476
1477 /* Call _exit(%r0). */
1478 "mov x8, %10\n"
1479 "svc 0x0\n"
1480 "1:\n"
1481
1482 : "=r"(res)
1483 : "i"(-EINVAL), "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg),
1484 "r"(__ptid), "r"(__tls), "r"(__ctid), "i"(__NR_clone), "i"(__NR_exit)
1485 : "x30", "memory");
1486 return res;
1487 }
1488 # elif SANITIZER_LOONGARCH64
internal_clone(int (* fn)(void *),void * child_stack,int flags,void * arg,int * parent_tidptr,void * newtls,int * child_tidptr)1489 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1490 int *parent_tidptr, void *newtls, int *child_tidptr) {
1491 if (!fn || !child_stack)
1492 return -EINVAL;
1493
1494 CHECK_EQ(0, (uptr)child_stack % 16);
1495
1496 register int res __asm__("$a0");
1497 register int __flags __asm__("$a0") = flags;
1498 register void *__stack __asm__("$a1") = child_stack;
1499 register int *__ptid __asm__("$a2") = parent_tidptr;
1500 register int *__ctid __asm__("$a3") = child_tidptr;
1501 register void *__tls __asm__("$a4") = newtls;
1502 register int (*__fn)(void *) __asm__("$a5") = fn;
1503 register void *__arg __asm__("$a6") = arg;
1504 register int nr_clone __asm__("$a7") = __NR_clone;
1505
1506 __asm__ __volatile__(
1507 "syscall 0\n"
1508
1509 // if ($a0 != 0)
1510 // return $a0;
1511 "bnez $a0, 1f\n"
1512
1513 // In the child, now. Call "fn(arg)".
1514 "move $a0, $a6\n"
1515 "jirl $ra, $a5, 0\n"
1516
1517 // Call _exit($a0).
1518 "addi.d $a7, $zero, %9\n"
1519 "syscall 0\n"
1520
1521 "1:\n"
1522
1523 : "=r"(res)
1524 : "0"(__flags), "r"(__stack), "r"(__ptid), "r"(__ctid), "r"(__tls),
1525 "r"(__fn), "r"(__arg), "r"(nr_clone), "i"(__NR_exit)
1526 : "memory", "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7",
1527 "$t8");
1528 return res;
1529 }
1530 # elif defined(__powerpc64__)
internal_clone(int (* fn)(void *),void * child_stack,int flags,void * arg,int * parent_tidptr,void * newtls,int * child_tidptr)1531 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1532 int *parent_tidptr, void *newtls, int *child_tidptr) {
1533 long long res;
1534 // Stack frame structure.
1535 # if SANITIZER_PPC64V1
1536 // Back chain == 0 (SP + 112)
1537 // Frame (112 bytes):
1538 // Parameter save area (SP + 48), 8 doublewords
1539 // TOC save area (SP + 40)
1540 // Link editor doubleword (SP + 32)
1541 // Compiler doubleword (SP + 24)
1542 // LR save area (SP + 16)
1543 // CR save area (SP + 8)
1544 // Back chain (SP + 0)
1545 # define FRAME_SIZE 112
1546 # define FRAME_TOC_SAVE_OFFSET 40
1547 # elif SANITIZER_PPC64V2
1548 // Back chain == 0 (SP + 32)
1549 // Frame (32 bytes):
1550 // TOC save area (SP + 24)
1551 // LR save area (SP + 16)
1552 // CR save area (SP + 8)
1553 // Back chain (SP + 0)
1554 # define FRAME_SIZE 32
1555 # define FRAME_TOC_SAVE_OFFSET 24
1556 # else
1557 # error "Unsupported PPC64 ABI"
1558 # endif
1559 if (!fn || !child_stack)
1560 return -EINVAL;
1561 CHECK_EQ(0, (uptr)child_stack % 16);
1562
1563 register int (*__fn)(void *) __asm__("r3") = fn;
1564 register void *__cstack __asm__("r4") = child_stack;
1565 register int __flags __asm__("r5") = flags;
1566 register void *__arg __asm__("r6") = arg;
1567 register int *__ptidptr __asm__("r7") = parent_tidptr;
1568 register void *__newtls __asm__("r8") = newtls;
1569 register int *__ctidptr __asm__("r9") = child_tidptr;
1570
1571 __asm__ __volatile__(
1572 /* fn and arg are saved across the syscall */
1573 "mr 28, %5\n\t"
1574 "mr 27, %8\n\t"
1575
1576 /* syscall
1577 r0 == __NR_clone
1578 r3 == flags
1579 r4 == child_stack
1580 r5 == parent_tidptr
1581 r6 == newtls
1582 r7 == child_tidptr */
1583 "mr 3, %7\n\t"
1584 "mr 5, %9\n\t"
1585 "mr 6, %10\n\t"
1586 "mr 7, %11\n\t"
1587 "li 0, %3\n\t"
1588 "sc\n\t"
1589
1590 /* Test if syscall was successful */
1591 "cmpdi cr1, 3, 0\n\t"
1592 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t"
1593 "bne- cr1, 1f\n\t"
1594
1595 /* Set up stack frame */
1596 "li 29, 0\n\t"
1597 "stdu 29, -8(1)\n\t"
1598 "stdu 1, -%12(1)\n\t"
1599 /* Do the function call */
1600 "std 2, %13(1)\n\t"
1601 # if SANITIZER_PPC64V1
1602 "ld 0, 0(28)\n\t"
1603 "ld 2, 8(28)\n\t"
1604 "mtctr 0\n\t"
1605 # elif SANITIZER_PPC64V2
1606 "mr 12, 28\n\t"
1607 "mtctr 12\n\t"
1608 # else
1609 # error "Unsupported PPC64 ABI"
1610 # endif
1611 "mr 3, 27\n\t"
1612 "bctrl\n\t"
1613 "ld 2, %13(1)\n\t"
1614
1615 /* Call _exit(r3) */
1616 "li 0, %4\n\t"
1617 "sc\n\t"
1618
1619 /* Return to parent */
1620 "1:\n\t"
1621 "mr %0, 3\n\t"
1622 : "=r"(res)
1623 : "0"(-1), "i"(EINVAL), "i"(__NR_clone), "i"(__NR_exit), "r"(__fn),
1624 "r"(__cstack), "r"(__flags), "r"(__arg), "r"(__ptidptr), "r"(__newtls),
1625 "r"(__ctidptr), "i"(FRAME_SIZE), "i"(FRAME_TOC_SAVE_OFFSET)
1626 : "cr0", "cr1", "memory", "ctr", "r0", "r27", "r28", "r29");
1627 return res;
1628 }
1629 # elif defined(__i386__)
internal_clone(int (* fn)(void *),void * child_stack,int flags,void * arg,int * parent_tidptr,void * newtls,int * child_tidptr)1630 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1631 int *parent_tidptr, void *newtls, int *child_tidptr) {
1632 int res;
1633 if (!fn || !child_stack)
1634 return -EINVAL;
1635 CHECK_EQ(0, (uptr)child_stack % 16);
1636 child_stack = (char *)child_stack - 7 * sizeof(unsigned int);
1637 ((unsigned int *)child_stack)[0] = (uptr)flags;
1638 ((unsigned int *)child_stack)[1] = (uptr)0;
1639 ((unsigned int *)child_stack)[2] = (uptr)fn;
1640 ((unsigned int *)child_stack)[3] = (uptr)arg;
1641 __asm__ __volatile__(
1642 /* %eax = syscall(%eax = SYSCALL(clone),
1643 * %ebx = flags,
1644 * %ecx = child_stack,
1645 * %edx = parent_tidptr,
1646 * %esi = new_tls,
1647 * %edi = child_tidptr)
1648 */
1649
1650 /* Obtain flags */
1651 "movl (%%ecx), %%ebx\n"
1652 /* Do the system call */
1653 "pushl %%ebx\n"
1654 "pushl %%esi\n"
1655 "pushl %%edi\n"
1656 /* Remember the flag value. */
1657 "movl %%ebx, (%%ecx)\n"
1658 "int $0x80\n"
1659 "popl %%edi\n"
1660 "popl %%esi\n"
1661 "popl %%ebx\n"
1662
1663 /* if (%eax != 0)
1664 * return;
1665 */
1666
1667 "test %%eax,%%eax\n"
1668 "jnz 1f\n"
1669
1670 /* terminate the stack frame */
1671 "xorl %%ebp,%%ebp\n"
1672 /* Call FN. */
1673 "call *%%ebx\n"
1674 # ifdef PIC
1675 "call here\n"
1676 "here:\n"
1677 "popl %%ebx\n"
1678 "addl $_GLOBAL_OFFSET_TABLE_+[.-here], %%ebx\n"
1679 # endif
1680 /* Call exit */
1681 "movl %%eax, %%ebx\n"
1682 "movl %2, %%eax\n"
1683 "int $0x80\n"
1684 "1:\n"
1685 : "=a"(res)
1686 : "a"(SYSCALL(clone)), "i"(SYSCALL(exit)), "c"(child_stack),
1687 "d"(parent_tidptr), "S"(newtls), "D"(child_tidptr)
1688 : "memory");
1689 return res;
1690 }
1691 # elif defined(__arm__)
internal_clone(int (* fn)(void *),void * child_stack,int flags,void * arg,int * parent_tidptr,void * newtls,int * child_tidptr)1692 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1693 int *parent_tidptr, void *newtls, int *child_tidptr) {
1694 unsigned int res;
1695 if (!fn || !child_stack)
1696 return -EINVAL;
1697 child_stack = (char *)child_stack - 2 * sizeof(unsigned int);
1698 ((unsigned int *)child_stack)[0] = (uptr)fn;
1699 ((unsigned int *)child_stack)[1] = (uptr)arg;
1700 register int r0 __asm__("r0") = flags;
1701 register void *r1 __asm__("r1") = child_stack;
1702 register int *r2 __asm__("r2") = parent_tidptr;
1703 register void *r3 __asm__("r3") = newtls;
1704 register int *r4 __asm__("r4") = child_tidptr;
1705 register int r7 __asm__("r7") = __NR_clone;
1706
1707 # if __ARM_ARCH > 4 || defined(__ARM_ARCH_4T__)
1708 # define ARCH_HAS_BX
1709 # endif
1710 # if __ARM_ARCH > 4
1711 # define ARCH_HAS_BLX
1712 # endif
1713
1714 # ifdef ARCH_HAS_BX
1715 # ifdef ARCH_HAS_BLX
1716 # define BLX(R) "blx " #R "\n"
1717 # else
1718 # define BLX(R) "mov lr, pc; bx " #R "\n"
1719 # endif
1720 # else
1721 # define BLX(R) "mov lr, pc; mov pc," #R "\n"
1722 # endif
1723
1724 __asm__ __volatile__(
1725 /* %r0 = syscall(%r7 = SYSCALL(clone),
1726 * %r0 = flags,
1727 * %r1 = child_stack,
1728 * %r2 = parent_tidptr,
1729 * %r3 = new_tls,
1730 * %r4 = child_tidptr)
1731 */
1732
1733 /* Do the system call */
1734 "swi 0x0\n"
1735
1736 /* if (%r0 != 0)
1737 * return %r0;
1738 */
1739 "cmp r0, #0\n"
1740 "bne 1f\n"
1741
1742 /* In the child, now. Call "fn(arg)". */
1743 "ldr r0, [sp, #4]\n"
1744 "ldr ip, [sp], #8\n" BLX(ip)
1745 /* Call _exit(%r0). */
1746 "mov r7, %7\n"
1747 "swi 0x0\n"
1748 "1:\n"
1749 "mov %0, r0\n"
1750 : "=r"(res)
1751 : "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r7), "i"(__NR_exit)
1752 : "memory");
1753 return res;
1754 }
1755 # endif
1756 # endif // SANITIZER_LINUX
1757
1758 # if SANITIZER_LINUX
internal_uname(struct utsname * buf)1759 int internal_uname(struct utsname *buf) {
1760 return internal_syscall(SYSCALL(uname), buf);
1761 }
1762 # endif
1763
1764 # if SANITIZER_ANDROID
1765 # if __ANDROID_API__ < 21
1766 extern "C" __attribute__((weak)) int dl_iterate_phdr(
1767 int (*)(struct dl_phdr_info *, size_t, void *), void *);
1768 # endif
1769
dl_iterate_phdr_test_cb(struct dl_phdr_info * info,size_t size,void * data)1770 static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size,
1771 void *data) {
1772 // Any name starting with "lib" indicates a bug in L where library base names
1773 // are returned instead of paths.
1774 if (info->dlpi_name && info->dlpi_name[0] == 'l' &&
1775 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') {
1776 *(bool *)data = true;
1777 return 1;
1778 }
1779 return 0;
1780 }
1781
1782 static atomic_uint32_t android_api_level;
1783
AndroidDetectApiLevelStatic()1784 static AndroidApiLevel AndroidDetectApiLevelStatic() {
1785 # if __ANDROID_API__ <= 19
1786 return ANDROID_KITKAT;
1787 # elif __ANDROID_API__ <= 22
1788 return ANDROID_LOLLIPOP_MR1;
1789 # else
1790 return ANDROID_POST_LOLLIPOP;
1791 # endif
1792 }
1793
AndroidDetectApiLevel()1794 static AndroidApiLevel AndroidDetectApiLevel() {
1795 if (!&dl_iterate_phdr)
1796 return ANDROID_KITKAT; // K or lower
1797 bool base_name_seen = false;
1798 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen);
1799 if (base_name_seen)
1800 return ANDROID_LOLLIPOP_MR1; // L MR1
1801 return ANDROID_POST_LOLLIPOP; // post-L
1802 // Plain L (API level 21) is completely broken wrt ASan and not very
1803 // interesting to detect.
1804 }
1805
1806 extern "C" __attribute__((weak)) void *_DYNAMIC;
1807
AndroidGetApiLevel()1808 AndroidApiLevel AndroidGetApiLevel() {
1809 AndroidApiLevel level =
1810 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed);
1811 if (level)
1812 return level;
1813 level = &_DYNAMIC == nullptr ? AndroidDetectApiLevelStatic()
1814 : AndroidDetectApiLevel();
1815 atomic_store(&android_api_level, level, memory_order_relaxed);
1816 return level;
1817 }
1818
1819 # endif
1820
GetHandleSignalModeImpl(int signum)1821 static HandleSignalMode GetHandleSignalModeImpl(int signum) {
1822 switch (signum) {
1823 case SIGABRT:
1824 return common_flags()->handle_abort;
1825 case SIGILL:
1826 return common_flags()->handle_sigill;
1827 case SIGTRAP:
1828 return common_flags()->handle_sigtrap;
1829 case SIGFPE:
1830 return common_flags()->handle_sigfpe;
1831 case SIGSEGV:
1832 return common_flags()->handle_segv;
1833 case SIGBUS:
1834 return common_flags()->handle_sigbus;
1835 }
1836 return kHandleSignalNo;
1837 }
1838
GetHandleSignalMode(int signum)1839 HandleSignalMode GetHandleSignalMode(int signum) {
1840 HandleSignalMode result = GetHandleSignalModeImpl(signum);
1841 if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler)
1842 return kHandleSignalExclusive;
1843 return result;
1844 }
1845
1846 # if !SANITIZER_GO
internal_start_thread(void * (* func)(void * arg),void * arg)1847 void *internal_start_thread(void *(*func)(void *arg), void *arg) {
1848 if (&real_pthread_create == 0)
1849 return nullptr;
1850 // Start the thread with signals blocked, otherwise it can steal user signals.
1851 ScopedBlockSignals block(nullptr);
1852 void *th;
1853 real_pthread_create(&th, nullptr, func, arg);
1854 return th;
1855 }
1856
internal_join_thread(void * th)1857 void internal_join_thread(void *th) {
1858 if (&real_pthread_join)
1859 real_pthread_join(th, nullptr);
1860 }
1861 # else
internal_start_thread(void * (* func)(void *),void * arg)1862 void *internal_start_thread(void *(*func)(void *), void *arg) { return 0; }
1863
internal_join_thread(void * th)1864 void internal_join_thread(void *th) {}
1865 # endif
1866
1867 # if SANITIZER_LINUX && defined(__aarch64__)
1868 // Android headers in the older NDK releases miss this definition.
1869 struct __sanitizer_esr_context {
1870 struct _aarch64_ctx head;
1871 uint64_t esr;
1872 };
1873
Aarch64GetESR(ucontext_t * ucontext,u64 * esr)1874 static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) {
1875 static const u32 kEsrMagic = 0x45535201;
1876 u8 *aux = reinterpret_cast<u8 *>(ucontext->uc_mcontext.__reserved);
1877 while (true) {
1878 _aarch64_ctx *ctx = (_aarch64_ctx *)aux;
1879 if (ctx->size == 0)
1880 break;
1881 if (ctx->magic == kEsrMagic) {
1882 *esr = ((__sanitizer_esr_context *)ctx)->esr;
1883 return true;
1884 }
1885 aux += ctx->size;
1886 }
1887 return false;
1888 }
1889 # elif SANITIZER_FREEBSD && defined(__aarch64__)
1890 // FreeBSD doesn't provide ESR in the ucontext.
Aarch64GetESR(ucontext_t * ucontext,u64 * esr)1891 static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) { return false; }
1892 # endif
1893
1894 using Context = ucontext_t;
1895
GetWriteFlag() const1896 SignalContext::WriteFlag SignalContext::GetWriteFlag() const {
1897 Context *ucontext = (Context *)context;
1898 # if defined(__x86_64__) || defined(__i386__)
1899 static const uptr PF_WRITE = 1U << 1;
1900 # if SANITIZER_FREEBSD
1901 uptr err = ucontext->uc_mcontext.mc_err;
1902 # elif SANITIZER_NETBSD
1903 uptr err = ucontext->uc_mcontext.__gregs[_REG_ERR];
1904 # elif SANITIZER_SOLARIS && defined(__i386__)
1905 const int Err = 13;
1906 uptr err = ucontext->uc_mcontext.gregs[Err];
1907 # else
1908 uptr err = ucontext->uc_mcontext.gregs[REG_ERR];
1909 # endif // SANITIZER_FREEBSD
1910 return err & PF_WRITE ? Write : Read;
1911 # elif defined(__mips__)
1912 uint32_t *exception_source;
1913 uint32_t faulty_instruction;
1914 uint32_t op_code;
1915
1916 exception_source = (uint32_t *)ucontext->uc_mcontext.pc;
1917 faulty_instruction = (uint32_t)(*exception_source);
1918
1919 op_code = (faulty_instruction >> 26) & 0x3f;
1920
1921 // FIXME: Add support for FPU, microMIPS, DSP, MSA memory instructions.
1922 switch (op_code) {
1923 case 0x28: // sb
1924 case 0x29: // sh
1925 case 0x2b: // sw
1926 case 0x3f: // sd
1927 # if __mips_isa_rev < 6
1928 case 0x2c: // sdl
1929 case 0x2d: // sdr
1930 case 0x2a: // swl
1931 case 0x2e: // swr
1932 # endif
1933 return SignalContext::Write;
1934
1935 case 0x20: // lb
1936 case 0x24: // lbu
1937 case 0x21: // lh
1938 case 0x25: // lhu
1939 case 0x23: // lw
1940 case 0x27: // lwu
1941 case 0x37: // ld
1942 # if __mips_isa_rev < 6
1943 case 0x1a: // ldl
1944 case 0x1b: // ldr
1945 case 0x22: // lwl
1946 case 0x26: // lwr
1947 # endif
1948 return SignalContext::Read;
1949 # if __mips_isa_rev == 6
1950 case 0x3b: // pcrel
1951 op_code = (faulty_instruction >> 19) & 0x3;
1952 switch (op_code) {
1953 case 0x1: // lwpc
1954 case 0x2: // lwupc
1955 return SignalContext::Read;
1956 }
1957 # endif
1958 }
1959 return SignalContext::Unknown;
1960 # elif defined(__arm__)
1961 static const uptr FSR_WRITE = 1U << 11;
1962 uptr fsr = ucontext->uc_mcontext.error_code;
1963 return fsr & FSR_WRITE ? Write : Read;
1964 # elif defined(__aarch64__)
1965 static const u64 ESR_ELx_WNR = 1U << 6;
1966 u64 esr;
1967 if (!Aarch64GetESR(ucontext, &esr))
1968 return Unknown;
1969 return esr & ESR_ELx_WNR ? Write : Read;
1970 # elif defined(__loongarch__)
1971 u32 flags = ucontext->uc_mcontext.__flags;
1972 if (flags & SC_ADDRERR_RD)
1973 return SignalContext::Read;
1974 if (flags & SC_ADDRERR_WR)
1975 return SignalContext::Write;
1976 return SignalContext::Unknown;
1977 # elif defined(__sparc__)
1978 // Decode the instruction to determine the access type.
1979 // From OpenSolaris $SRC/uts/sun4/os/trap.c (get_accesstype).
1980 # if SANITIZER_SOLARIS
1981 uptr pc = ucontext->uc_mcontext.gregs[REG_PC];
1982 # else
1983 // Historical BSDism here.
1984 struct sigcontext *scontext = (struct sigcontext *)context;
1985 # if defined(__arch64__)
1986 uptr pc = scontext->sigc_regs.tpc;
1987 # else
1988 uptr pc = scontext->si_regs.pc;
1989 # endif
1990 # endif
1991 u32 instr = *(u32 *)pc;
1992 return (instr >> 21) & 1 ? Write : Read;
1993 # elif defined(__riscv)
1994 # if SANITIZER_FREEBSD
1995 unsigned long pc = ucontext->uc_mcontext.mc_gpregs.gp_sepc;
1996 # else
1997 unsigned long pc = ucontext->uc_mcontext.__gregs[REG_PC];
1998 # endif
1999 unsigned faulty_instruction = *(uint16_t *)pc;
2000
2001 # if defined(__riscv_compressed)
2002 if ((faulty_instruction & 0x3) != 0x3) { // it's a compressed instruction
2003 // set op_bits to the instruction bits [1, 0, 15, 14, 13]
2004 unsigned op_bits =
2005 ((faulty_instruction & 0x3) << 3) | (faulty_instruction >> 13);
2006 unsigned rd = faulty_instruction & 0xF80; // bits 7-11, inclusive
2007 switch (op_bits) {
2008 case 0b10'010: // c.lwsp (rd != x0)
2009 # if __riscv_xlen == 64
2010 case 0b10'011: // c.ldsp (rd != x0)
2011 # endif
2012 return rd ? SignalContext::Read : SignalContext::Unknown;
2013 case 0b00'010: // c.lw
2014 # if __riscv_flen >= 32 && __riscv_xlen == 32
2015 case 0b10'011: // c.flwsp
2016 # endif
2017 # if __riscv_flen >= 32 || __riscv_xlen == 64
2018 case 0b00'011: // c.flw / c.ld
2019 # endif
2020 # if __riscv_flen == 64
2021 case 0b00'001: // c.fld
2022 case 0b10'001: // c.fldsp
2023 # endif
2024 return SignalContext::Read;
2025 case 0b00'110: // c.sw
2026 case 0b10'110: // c.swsp
2027 # if __riscv_flen >= 32 || __riscv_xlen == 64
2028 case 0b00'111: // c.fsw / c.sd
2029 case 0b10'111: // c.fswsp / c.sdsp
2030 # endif
2031 # if __riscv_flen == 64
2032 case 0b00'101: // c.fsd
2033 case 0b10'101: // c.fsdsp
2034 # endif
2035 return SignalContext::Write;
2036 default:
2037 return SignalContext::Unknown;
2038 }
2039 }
2040 # endif
2041
2042 unsigned opcode = faulty_instruction & 0x7f; // lower 7 bits
2043 unsigned funct3 = (faulty_instruction >> 12) & 0x7; // bits 12-14, inclusive
2044 switch (opcode) {
2045 case 0b0000011: // loads
2046 switch (funct3) {
2047 case 0b000: // lb
2048 case 0b001: // lh
2049 case 0b010: // lw
2050 # if __riscv_xlen == 64
2051 case 0b011: // ld
2052 # endif
2053 case 0b100: // lbu
2054 case 0b101: // lhu
2055 return SignalContext::Read;
2056 default:
2057 return SignalContext::Unknown;
2058 }
2059 case 0b0100011: // stores
2060 switch (funct3) {
2061 case 0b000: // sb
2062 case 0b001: // sh
2063 case 0b010: // sw
2064 # if __riscv_xlen == 64
2065 case 0b011: // sd
2066 # endif
2067 return SignalContext::Write;
2068 default:
2069 return SignalContext::Unknown;
2070 }
2071 # if __riscv_flen >= 32
2072 case 0b0000111: // floating-point loads
2073 switch (funct3) {
2074 case 0b010: // flw
2075 # if __riscv_flen == 64
2076 case 0b011: // fld
2077 # endif
2078 return SignalContext::Read;
2079 default:
2080 return SignalContext::Unknown;
2081 }
2082 case 0b0100111: // floating-point stores
2083 switch (funct3) {
2084 case 0b010: // fsw
2085 # if __riscv_flen == 64
2086 case 0b011: // fsd
2087 # endif
2088 return SignalContext::Write;
2089 default:
2090 return SignalContext::Unknown;
2091 }
2092 # endif
2093 default:
2094 return SignalContext::Unknown;
2095 }
2096 # else
2097 (void)ucontext;
2098 return Unknown; // FIXME: Implement.
2099 # endif
2100 }
2101
IsTrueFaultingAddress() const2102 bool SignalContext::IsTrueFaultingAddress() const {
2103 auto si = static_cast<const siginfo_t *>(siginfo);
2104 // SIGSEGV signals without a true fault address have si_code set to 128.
2105 return si->si_signo == SIGSEGV && si->si_code != 128;
2106 }
2107
DumpAllRegisters(void * context)2108 void SignalContext::DumpAllRegisters(void *context) {
2109 // FIXME: Implement this.
2110 }
2111
GetPcSpBp(void * context,uptr * pc,uptr * sp,uptr * bp)2112 static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) {
2113 # if SANITIZER_NETBSD
2114 // This covers all NetBSD architectures
2115 ucontext_t *ucontext = (ucontext_t *)context;
2116 *pc = _UC_MACHINE_PC(ucontext);
2117 *bp = _UC_MACHINE_FP(ucontext);
2118 *sp = _UC_MACHINE_SP(ucontext);
2119 # elif defined(__arm__)
2120 ucontext_t *ucontext = (ucontext_t *)context;
2121 *pc = ucontext->uc_mcontext.arm_pc;
2122 *bp = ucontext->uc_mcontext.arm_fp;
2123 *sp = ucontext->uc_mcontext.arm_sp;
2124 # elif defined(__aarch64__)
2125 # if SANITIZER_FREEBSD
2126 ucontext_t *ucontext = (ucontext_t *)context;
2127 *pc = ucontext->uc_mcontext.mc_gpregs.gp_elr;
2128 *bp = ucontext->uc_mcontext.mc_gpregs.gp_x[29];
2129 *sp = ucontext->uc_mcontext.mc_gpregs.gp_sp;
2130 # else
2131 ucontext_t *ucontext = (ucontext_t *)context;
2132 *pc = ucontext->uc_mcontext.pc;
2133 *bp = ucontext->uc_mcontext.regs[29];
2134 *sp = ucontext->uc_mcontext.sp;
2135 # endif
2136 # elif defined(__hppa__)
2137 ucontext_t *ucontext = (ucontext_t *)context;
2138 *pc = ucontext->uc_mcontext.sc_iaoq[0];
2139 /* GCC uses %r3 whenever a frame pointer is needed. */
2140 *bp = ucontext->uc_mcontext.sc_gr[3];
2141 *sp = ucontext->uc_mcontext.sc_gr[30];
2142 # elif defined(__x86_64__)
2143 # if SANITIZER_FREEBSD
2144 ucontext_t *ucontext = (ucontext_t *)context;
2145 *pc = ucontext->uc_mcontext.mc_rip;
2146 *bp = ucontext->uc_mcontext.mc_rbp;
2147 *sp = ucontext->uc_mcontext.mc_rsp;
2148 # else
2149 ucontext_t *ucontext = (ucontext_t *)context;
2150 *pc = ucontext->uc_mcontext.gregs[REG_RIP];
2151 *bp = ucontext->uc_mcontext.gregs[REG_RBP];
2152 *sp = ucontext->uc_mcontext.gregs[REG_RSP];
2153 # endif
2154 # elif defined(__i386__)
2155 # if SANITIZER_FREEBSD
2156 ucontext_t *ucontext = (ucontext_t *)context;
2157 *pc = ucontext->uc_mcontext.mc_eip;
2158 *bp = ucontext->uc_mcontext.mc_ebp;
2159 *sp = ucontext->uc_mcontext.mc_esp;
2160 # else
2161 ucontext_t *ucontext = (ucontext_t *)context;
2162 # if SANITIZER_SOLARIS
2163 /* Use the numeric values: the symbolic ones are undefined by llvm
2164 include/llvm/Support/Solaris.h. */
2165 # ifndef REG_EIP
2166 # define REG_EIP 14 // REG_PC
2167 # endif
2168 # ifndef REG_EBP
2169 # define REG_EBP 6 // REG_FP
2170 # endif
2171 # ifndef REG_UESP
2172 # define REG_UESP 17 // REG_SP
2173 # endif
2174 # endif
2175 *pc = ucontext->uc_mcontext.gregs[REG_EIP];
2176 *bp = ucontext->uc_mcontext.gregs[REG_EBP];
2177 *sp = ucontext->uc_mcontext.gregs[REG_UESP];
2178 # endif
2179 # elif defined(__powerpc__) || defined(__powerpc64__)
2180 # if SANITIZER_FREEBSD
2181 ucontext_t *ucontext = (ucontext_t *)context;
2182 *pc = ucontext->uc_mcontext.mc_srr0;
2183 *sp = ucontext->uc_mcontext.mc_frame[1];
2184 *bp = ucontext->uc_mcontext.mc_frame[31];
2185 # else
2186 ucontext_t *ucontext = (ucontext_t *)context;
2187 *pc = ucontext->uc_mcontext.regs->nip;
2188 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1];
2189 // The powerpc{,64}-linux ABIs do not specify r31 as the frame
2190 // pointer, but GCC always uses r31 when we need a frame pointer.
2191 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31];
2192 # endif
2193 # elif defined(__sparc__)
2194 # if defined(__arch64__) || defined(__sparcv9)
2195 # define STACK_BIAS 2047
2196 # else
2197 # define STACK_BIAS 0
2198 # endif
2199 # if SANITIZER_SOLARIS
2200 ucontext_t *ucontext = (ucontext_t *)context;
2201 *pc = ucontext->uc_mcontext.gregs[REG_PC];
2202 *sp = ucontext->uc_mcontext.gregs[REG_O6] + STACK_BIAS;
2203 # else
2204 // Historical BSDism here.
2205 struct sigcontext *scontext = (struct sigcontext *)context;
2206 # if defined(__arch64__)
2207 *pc = scontext->sigc_regs.tpc;
2208 *sp = scontext->sigc_regs.u_regs[14] + STACK_BIAS;
2209 # else
2210 *pc = scontext->si_regs.pc;
2211 *sp = scontext->si_regs.u_regs[14];
2212 # endif
2213 # endif
2214 *bp = (uptr)((uhwptr *)*sp)[14] + STACK_BIAS;
2215 # elif defined(__mips__)
2216 ucontext_t *ucontext = (ucontext_t *)context;
2217 *pc = ucontext->uc_mcontext.pc;
2218 *bp = ucontext->uc_mcontext.gregs[30];
2219 *sp = ucontext->uc_mcontext.gregs[29];
2220 # elif defined(__s390__)
2221 ucontext_t *ucontext = (ucontext_t *)context;
2222 # if defined(__s390x__)
2223 *pc = ucontext->uc_mcontext.psw.addr;
2224 # else
2225 *pc = ucontext->uc_mcontext.psw.addr & 0x7fffffff;
2226 # endif
2227 *bp = ucontext->uc_mcontext.gregs[11];
2228 *sp = ucontext->uc_mcontext.gregs[15];
2229 # elif defined(__riscv)
2230 ucontext_t *ucontext = (ucontext_t *)context;
2231 # if SANITIZER_FREEBSD
2232 *pc = ucontext->uc_mcontext.mc_gpregs.gp_sepc;
2233 *bp = ucontext->uc_mcontext.mc_gpregs.gp_s[0];
2234 *sp = ucontext->uc_mcontext.mc_gpregs.gp_sp;
2235 # else
2236 *pc = ucontext->uc_mcontext.__gregs[REG_PC];
2237 *bp = ucontext->uc_mcontext.__gregs[REG_S0];
2238 *sp = ucontext->uc_mcontext.__gregs[REG_SP];
2239 # endif
2240 # elif defined(__hexagon__)
2241 ucontext_t *ucontext = (ucontext_t *)context;
2242 *pc = ucontext->uc_mcontext.pc;
2243 *bp = ucontext->uc_mcontext.r30;
2244 *sp = ucontext->uc_mcontext.r29;
2245 # elif defined(__loongarch__)
2246 ucontext_t *ucontext = (ucontext_t *)context;
2247 *pc = ucontext->uc_mcontext.__pc;
2248 *bp = ucontext->uc_mcontext.__gregs[22];
2249 *sp = ucontext->uc_mcontext.__gregs[3];
2250 # else
2251 # error "Unsupported arch"
2252 # endif
2253 }
2254
InitPcSpBp()2255 void SignalContext::InitPcSpBp() { GetPcSpBp(context, &pc, &sp, &bp); }
2256
InitializePlatformEarly()2257 void InitializePlatformEarly() {
2258 // Do nothing.
2259 }
2260
CheckASLR()2261 void CheckASLR() {
2262 # if SANITIZER_NETBSD
2263 int mib[3];
2264 int paxflags;
2265 uptr len = sizeof(paxflags);
2266
2267 mib[0] = CTL_PROC;
2268 mib[1] = internal_getpid();
2269 mib[2] = PROC_PID_PAXFLAGS;
2270
2271 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) {
2272 Printf("sysctl failed\n");
2273 Die();
2274 }
2275
2276 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_ASLR)) {
2277 Printf(
2278 "This sanitizer is not compatible with enabled ASLR.\n"
2279 "To disable ASLR, please run \"paxctl +a %s\" and try again.\n",
2280 GetArgv()[0]);
2281 Die();
2282 }
2283 # elif SANITIZER_FREEBSD
2284 int aslr_status;
2285 int r = internal_procctl(P_PID, 0, PROC_ASLR_STATUS, &aslr_status);
2286 if (UNLIKELY(r == -1)) {
2287 // We're making things less 'dramatic' here since
2288 // the cmd is not necessarily guaranteed to be here
2289 // just yet regarding FreeBSD release
2290 return;
2291 }
2292 if ((aslr_status & PROC_ASLR_ACTIVE) != 0) {
2293 VReport(1,
2294 "This sanitizer is not compatible with enabled ASLR "
2295 "and binaries compiled with PIE\n"
2296 "ASLR will be disabled and the program re-executed.\n");
2297 int aslr_ctl = PROC_ASLR_FORCE_DISABLE;
2298 CHECK_NE(internal_procctl(P_PID, 0, PROC_ASLR_CTL, &aslr_ctl), -1);
2299 ReExec();
2300 }
2301 # elif SANITIZER_PPC64V2
2302 // Disable ASLR for Linux PPC64LE.
2303 int old_personality = personality(0xffffffff);
2304 if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) {
2305 VReport(1,
2306 "WARNING: Program is being run with address space layout "
2307 "randomization (ASLR) enabled which prevents the thread and "
2308 "memory sanitizers from working on powerpc64le.\n"
2309 "ASLR will be disabled and the program re-executed.\n");
2310 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1);
2311 ReExec();
2312 }
2313 # else
2314 // Do nothing
2315 # endif
2316 }
2317
CheckMPROTECT()2318 void CheckMPROTECT() {
2319 # if SANITIZER_NETBSD
2320 int mib[3];
2321 int paxflags;
2322 uptr len = sizeof(paxflags);
2323
2324 mib[0] = CTL_PROC;
2325 mib[1] = internal_getpid();
2326 mib[2] = PROC_PID_PAXFLAGS;
2327
2328 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) {
2329 Printf("sysctl failed\n");
2330 Die();
2331 }
2332
2333 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_MPROTECT)) {
2334 Printf("This sanitizer is not compatible with enabled MPROTECT\n");
2335 Die();
2336 }
2337 # else
2338 // Do nothing
2339 # endif
2340 }
2341
CheckNoDeepBind(const char * filename,int flag)2342 void CheckNoDeepBind(const char *filename, int flag) {
2343 # ifdef RTLD_DEEPBIND
2344 if (flag & RTLD_DEEPBIND) {
2345 Report(
2346 "You are trying to dlopen a %s shared library with RTLD_DEEPBIND flag"
2347 " which is incompatible with sanitizer runtime "
2348 "(see https://github.com/google/sanitizers/issues/611 for details"
2349 "). If you want to run %s library under sanitizers please remove "
2350 "RTLD_DEEPBIND from dlopen flags.\n",
2351 filename, filename);
2352 Die();
2353 }
2354 # endif
2355 }
2356
FindAvailableMemoryRange(uptr size,uptr alignment,uptr left_padding,uptr * largest_gap_found,uptr * max_occupied_addr)2357 uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding,
2358 uptr *largest_gap_found,
2359 uptr *max_occupied_addr) {
2360 UNREACHABLE("FindAvailableMemoryRange is not available");
2361 return 0;
2362 }
2363
GetRandom(void * buffer,uptr length,bool blocking)2364 bool GetRandom(void *buffer, uptr length, bool blocking) {
2365 if (!buffer || !length || length > 256)
2366 return false;
2367 # if SANITIZER_USE_GETENTROPY
2368 uptr rnd = getentropy(buffer, length);
2369 int rverrno = 0;
2370 if (internal_iserror(rnd, &rverrno) && rverrno == EFAULT)
2371 return false;
2372 else if (rnd == 0)
2373 return true;
2374 # endif // SANITIZER_USE_GETENTROPY
2375
2376 # if SANITIZER_USE_GETRANDOM
2377 static atomic_uint8_t skip_getrandom_syscall;
2378 if (!atomic_load_relaxed(&skip_getrandom_syscall)) {
2379 // Up to 256 bytes, getrandom will not be interrupted.
2380 uptr res = internal_syscall(SYSCALL(getrandom), buffer, length,
2381 blocking ? 0 : GRND_NONBLOCK);
2382 int rverrno = 0;
2383 if (internal_iserror(res, &rverrno) && rverrno == ENOSYS)
2384 atomic_store_relaxed(&skip_getrandom_syscall, 1);
2385 else if (res == length)
2386 return true;
2387 }
2388 # endif // SANITIZER_USE_GETRANDOM
2389 // Up to 256 bytes, a read off /dev/urandom will not be interrupted.
2390 // blocking is moot here, O_NONBLOCK has no effect when opening /dev/urandom.
2391 uptr fd = internal_open("/dev/urandom", O_RDONLY);
2392 if (internal_iserror(fd))
2393 return false;
2394 uptr res = internal_read(fd, buffer, length);
2395 if (internal_iserror(res))
2396 return false;
2397 internal_close(fd);
2398 return true;
2399 }
2400
2401 } // namespace __sanitizer
2402
2403 #endif
2404