Bug Summary

File:compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
Warning:line 377, column 3
Undefined or garbage value returned to caller

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name sanitizer_linux.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -fhalf-no-semantic-interposition -mframe-pointer=none -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -fno-split-dwarf-inlining -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-12/lib/clang/12.0.0 -D HAVE_RPC_XDR_H=1 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/build-llvm/projects/compiler-rt/lib/sanitizer_common -I /build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common -I /build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/build-llvm/include -I /build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/llvm/include -I /build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/.. -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-12/lib/clang/12.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -Wno-unused-parameter -Wno-variadic-macros -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/build-llvm/projects/compiler-rt/lib/sanitizer_common -fdebug-prefix-map=/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1=. -ferror-limit 19 -fvisibility hidden -fvisibility-inlines-hidden -fno-builtin -fno-rtti -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2021-01-24-223304-31662-1 -x c++ /build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp

/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp

→
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_FREEBSD0 || SANITIZER_LINUX1 || SANITIZER_NETBSD0 || \
17 SANITIZER_SOLARIS0
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_LINUX1 && !SANITIZER_GO0
30#include <asm/param.h>
31#endif
32
33// For mips64, syscall(__NR_stat) fills the buffer in the 'struct kernel_stat'
34// format. Struct kernel_stat is defined as 'struct stat' in asm/stat.h. To
35// access stat from asm/stat.h, without conflicting with definition in
36// sys/stat.h, we use this trick.
37#if defined(__mips64)
38#include <asm/unistd.h>
39#include <sys/types.h>
40#define stat kernel_stat
41#if SANITIZER_GO0
42#undef st_atimest_atim.tv_sec
43#undef st_mtimest_mtim.tv_sec
44#undef st_ctimest_ctim.tv_sec
45#define st_atimest_atim.tv_sec st_atim
46#define st_mtimest_mtim.tv_sec st_mtim
47#define st_ctimest_ctim.tv_sec st_ctim
48#endif
49#include <asm/stat.h>
50#undef stat
51#endif
52
53#include <dlfcn.h>
54#include <errno(*__errno_location ()).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#include <sys/param.h>
62#if !SANITIZER_SOLARIS0
63#include <sys/ptrace.h>
64#endif
65#include <sys/resource.h>
66#include <sys/stat.h>
67#include <sys/syscall.h>
68#include <sys/time.h>
69#include <sys/types.h>
70#include <ucontext.h>
71#include <unistd.h>
72
73#if SANITIZER_LINUX1
74#include <sys/utsname.h>
75#endif
76
77#if SANITIZER_LINUX1 && !SANITIZER_ANDROID0
78#include <sys/personality.h>
79#endif
80
81#if SANITIZER_FREEBSD0
82#include <sys/exec.h>
83#include <sys/sysctl.h>
84#include <machine/atomic.h>
85extern "C" {
86// <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on
87// FreeBSD 9.2 and 10.0.
88#include <sys/umtx.h>
89}
90#include <sys/thr.h>
91#endif // SANITIZER_FREEBSD
92
93#if SANITIZER_NETBSD0
94#include <limits.h> // For NAME_MAX
95#include <sys/sysctl.h>
96#include <sys/exec.h>
97extern struct ps_strings *__ps_strings;
98#endif // SANITIZER_NETBSD
99
100#if SANITIZER_SOLARIS0
101#include <stdlib.h>
102#include <thread.h>
103#define environ _environ
104#endif
105
106extern char **environ;
107
108#if SANITIZER_LINUX1
109// <linux/time.h>
110struct kernel_timeval {
111 long tv_sec;
112 long tv_usec;
113};
114
115// <linux/futex.h> is broken on some linux distributions.
116const int FUTEX_WAIT = 0;
117const int FUTEX_WAKE = 1;
118const int FUTEX_PRIVATE_FLAG = 128;
119const int FUTEX_WAIT_PRIVATE = FUTEX_WAIT | FUTEX_PRIVATE_FLAG;
120const int FUTEX_WAKE_PRIVATE = FUTEX_WAKE | FUTEX_PRIVATE_FLAG;
121#endif // SANITIZER_LINUX
122
123// Are we using 32-bit or 64-bit Linux syscalls?
124// x32 (which defines __x86_64__) has SANITIZER_WORDSIZE == 32
125// but it still needs to use 64-bit syscalls.
126#if SANITIZER_LINUX1 && (defined(__x86_64__1) || defined(__powerpc64__) || \
127 SANITIZER_WORDSIZE64 == 64)
128# define SANITIZER_LINUX_USES_64BIT_SYSCALLS1 1
129#else
130# define SANITIZER_LINUX_USES_64BIT_SYSCALLS1 0
131#endif
132
133// Note : FreeBSD had implemented both
134// Linux apis, available from
135// future 12.x version most likely
136#if SANITIZER_LINUX1 && defined(__NR_getrandom318)
137# if !defined(GRND_NONBLOCK1)
138# define GRND_NONBLOCK1 1
139# endif
140# define SANITIZER_USE_GETRANDOM1 1
141#else
142# define SANITIZER_USE_GETRANDOM1 0
143#endif // SANITIZER_LINUX && defined(__NR_getrandom)
144
145#if SANITIZER_FREEBSD0 && __FreeBSD_version >= 1200000
146# define SANITIZER_USE_GETENTROPY0 1
147#else
148# define SANITIZER_USE_GETENTROPY0 0
149#endif
150
151namespace __sanitizer {
152
153#if SANITIZER_LINUX1 && defined(__x86_64__1)
154#include "sanitizer_syscall_linux_x86_64.inc"
155#elif SANITIZER_LINUX1 && SANITIZER_RISCV640
156#include "sanitizer_syscall_linux_riscv64.inc"
157#elif SANITIZER_LINUX1 && defined(__aarch64__)
158#include "sanitizer_syscall_linux_aarch64.inc"
159#elif SANITIZER_LINUX1 && defined(__arm__)
160#include "sanitizer_syscall_linux_arm.inc"
161#else
162#include "sanitizer_syscall_generic.inc"
163#endif
164
165// --------------- sanitizer_libc.h
166#if !SANITIZER_SOLARIS0 && !SANITIZER_NETBSD0
167#if !SANITIZER_S3900
168uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd,
169 u64 offset) {
170#if SANITIZER_FREEBSD0 || SANITIZER_LINUX_USES_64BIT_SYSCALLS1
171 return internal_syscall(SYSCALL(mmap)9, (uptr)addr, length, prot, flags, fd,
172 offset);
173#else
174 // mmap2 specifies file offset in 4096-byte units.
175 CHECK(IsAligned(offset, 4096))do { __sanitizer::u64 v1 = (__sanitizer::u64)((IsAligned(offset
, 4096))); __sanitizer::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 175, "(" "(IsAligned(offset, 4096))" ") " "!=" " (" "0" ")"
, v1, v2); } while (false);
176 return internal_syscall(SYSCALL(mmap2)__NR_mmap2, addr, length, prot, flags, fd,
177 offset / 4096);
178#endif
179}
180#endif // !SANITIZER_S390
181
182uptr internal_munmap(void *addr, uptr length) {
183 return internal_syscall(SYSCALL(munmap)11, (uptr)addr, length);
184}
185
186int internal_mprotect(void *addr, uptr length, int prot) {
187 return internal_syscall(SYSCALL(mprotect)10, (uptr)addr, length, prot);
188}
189
190int internal_madvise(uptr addr, uptr length, int advice) {
191 return internal_syscall(SYSCALL(madvise)28, addr, length, advice);
192}
193
194uptr internal_close(fd_t fd) {
195 return internal_syscall(SYSCALL(close)3, fd);
196}
197
198uptr internal_open(const char *filename, int flags) {
199#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
200 return internal_syscall(SYSCALL(openat)257, AT_FDCWD-100, (uptr)filename, flags);
201#else
202 return internal_syscall(SYSCALL(open)2, (uptr)filename, flags);
203#endif
204}
205
206uptr internal_open(const char *filename, int flags, u32 mode) {
207#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
208 return internal_syscall(SYSCALL(openat)257, AT_FDCWD-100, (uptr)filename, flags,
209 mode);
210#else
211 return internal_syscall(SYSCALL(open)2, (uptr)filename, flags, mode);
212#endif
213}
214
215uptr internal_read(fd_t fd, void *buf, uptr count) {
216 sptr res;
217 HANDLE_EINTR(res,{ int rverrno; do { res = ((sptr)internal_syscall(0, fd, (uptr
)buf, count)); } while (internal_iserror(res, &rverrno) &&
rverrno == 4); }
218 (sptr)internal_syscall(SYSCALL(read), fd, (uptr)buf, count)){ int rverrno; do { res = ((sptr)internal_syscall(0, fd, (uptr
)buf, count)); } while (internal_iserror(res, &rverrno) &&
rverrno == 4); };
219 return res;
220}
221
222uptr internal_write(fd_t fd, const void *buf, uptr count) {
223 sptr res;
224 HANDLE_EINTR(res,{ int rverrno; do { res = ((sptr)internal_syscall(1, fd, (uptr
)buf, count)); } while (internal_iserror(res, &rverrno) &&
rverrno == 4); }
225 (sptr)internal_syscall(SYSCALL(write), fd, (uptr)buf, count)){ int rverrno; do { res = ((sptr)internal_syscall(1, fd, (uptr
)buf, count)); } while (internal_iserror(res, &rverrno) &&
rverrno == 4); };
226 return res;
227}
228
229uptr internal_ftruncate(fd_t fd, uptr size) {
230 sptr res;
231 HANDLE_EINTR(res, (sptr)internal_syscall(SYSCALL(ftruncate), fd,{ int rverrno; do { res = ((sptr)internal_syscall(77, fd, (OFF_T
)size)); } while (internal_iserror(res, &rverrno) &&
rverrno == 4); }
232 (OFF_T)size)){ int rverrno; do { res = ((sptr)internal_syscall(77, fd, (OFF_T
)size)); } while (internal_iserror(res, &rverrno) &&
rverrno == 4); };
233 return res;
234}
235
236#if !SANITIZER_LINUX_USES_64BIT_SYSCALLS1 && SANITIZER_LINUX1
237static void stat64_to_stat(struct stat64 *in, struct stat *out) {
238 internal_memset(out, 0, sizeof(*out));
239 out->st_dev = in->st_dev;
240 out->st_ino = in->st_ino;
241 out->st_mode = in->st_mode;
242 out->st_nlink = in->st_nlink;
243 out->st_uid = in->st_uid;
244 out->st_gid = in->st_gid;
245 out->st_rdev = in->st_rdev;
246 out->st_size = in->st_size;
247 out->st_blksize = in->st_blksize;
248 out->st_blocks = in->st_blocks;
249 out->st_atimest_atim.tv_sec = in->st_atimest_atim.tv_sec;
250 out->st_mtimest_mtim.tv_sec = in->st_mtimest_mtim.tv_sec;
251 out->st_ctimest_ctim.tv_sec = in->st_ctimest_ctim.tv_sec;
252}
253#endif
254
255#if defined(__mips64)
256// Undefine compatibility macros from <sys/stat.h>
257// so that they would not clash with the kernel_stat
258// st_[a|m|c]time fields
259#if !SANITIZER_GO0
260#undef st_atimest_atim.tv_sec
261#undef st_mtimest_mtim.tv_sec
262#undef st_ctimest_ctim.tv_sec
263#endif
264#if defined(SANITIZER_ANDROID0)
265// Bionic sys/stat.h defines additional macros
266// for compatibility with the old NDKs and
267// they clash with the kernel_stat structure
268// st_[a|m|c]time_nsec fields.
269#undef st_atime_nsec
270#undef st_mtime_nsec
271#undef st_ctime_nsec
272#endif
273static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) {
274 internal_memset(out, 0, sizeof(*out));
275 out->st_dev = in->st_dev;
276 out->st_ino = in->st_ino;
277 out->st_mode = in->st_mode;
278 out->st_nlink = in->st_nlink;
279 out->st_uid = in->st_uid;
280 out->st_gid = in->st_gid;
281 out->st_rdev = in->st_rdev;
282 out->st_size = in->st_size;
283 out->st_blksize = in->st_blksize;
284 out->st_blocks = in->st_blocks;
285#if defined(__USE_MISC1) || \
286 defined(__USE_XOPEN2K81) || \
287 defined(SANITIZER_ANDROID0)
288 out->st_atim.tv_sec = in->st_atimest_atim.tv_sec;
289 out->st_atim.tv_nsec = in->st_atime_nsec;
290 out->st_mtim.tv_sec = in->st_mtimest_mtim.tv_sec;
291 out->st_mtim.tv_nsec = in->st_mtime_nsec;
292 out->st_ctim.tv_sec = in->st_ctimest_ctim.tv_sec;
293 out->st_ctim.tv_nsec = in->st_ctime_nsec;
294#else
295 out->st_atimest_atim.tv_sec = in->st_atimest_atim.tv_sec;
296 out->st_atimensec = in->st_atime_nsec;
297 out->st_mtimest_mtim.tv_sec = in->st_mtimest_mtim.tv_sec;
298 out->st_mtimensec = in->st_mtime_nsec;
299 out->st_ctimest_ctim.tv_sec = in->st_ctimest_ctim.tv_sec;
300 out->st_atimensec = in->st_ctime_nsec;
301#endif
302}
303#endif
304
305uptr internal_stat(const char *path, void *buf) {
306#if SANITIZER_FREEBSD0
307 return internal_syscall(SYSCALL(fstatat)__NR_fstatat, AT_FDCWD-100, (uptr)path, (uptr)buf, 0);
308#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
309 return internal_syscall(SYSCALL(newfstatat)262, AT_FDCWD-100, (uptr)path, (uptr)buf,
310 0);
311#elif SANITIZER_LINUX_USES_64BIT_SYSCALLS1
312# if defined(__mips64)
313 // For mips64, stat syscall fills buffer in the format of kernel_stat
314 struct kernel_stat kbuf;
315 int res = internal_syscall(SYSCALL(stat)4, path, &kbuf);
316 kernel_stat_to_stat(&kbuf, (struct stat *)buf);
317 return res;
318# else
319 return internal_syscall(SYSCALL(stat)4, (uptr)path, (uptr)buf);
320# endif
321#else
322 struct stat64 buf64;
323 int res = internal_syscall(SYSCALL(stat64)__NR_stat64, path, &buf64);
324 stat64_to_stat(&buf64, (struct stat *)buf);
325 return res;
326#endif
327}
328
329uptr internal_lstat(const char *path, void *buf) {
330#if SANITIZER_FREEBSD0
331 return internal_syscall(SYSCALL(fstatat)__NR_fstatat, AT_FDCWD-100, (uptr)path, (uptr)buf,
332 AT_SYMLINK_NOFOLLOW0x100);
333#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
334 return internal_syscall(SYSCALL(newfstatat)262, AT_FDCWD-100, (uptr)path, (uptr)buf,
335 AT_SYMLINK_NOFOLLOW0x100);
336#elif SANITIZER_LINUX_USES_64BIT_SYSCALLS1
337# if SANITIZER_MIPS640
338 // For mips64, lstat syscall fills buffer in the format of kernel_stat
339 struct kernel_stat kbuf;
340 int res = internal_syscall(SYSCALL(lstat)6, path, &kbuf);
341 kernel_stat_to_stat(&kbuf, (struct stat *)buf);
342 return res;
343# else
344 return internal_syscall(SYSCALL(lstat)6, (uptr)path, (uptr)buf);
345# endif
346#else
347 struct stat64 buf64;
348 int res = internal_syscall(SYSCALL(lstat64)__NR_lstat64, path, &buf64);
349 stat64_to_stat(&buf64, (struct stat *)buf);
350 return res;
351#endif
352}
353
354uptr internal_fstat(fd_t fd, void *buf) {
355#if SANITIZER_FREEBSD0 || SANITIZER_LINUX_USES_64BIT_SYSCALLS1
356#if SANITIZER_MIPS640
357 // For mips64, fstat syscall fills buffer in the format of kernel_stat
358 struct kernel_stat kbuf;
359 int res = internal_syscall(SYSCALL(fstat)5, fd, &kbuf);
360 kernel_stat_to_stat(&kbuf, (struct stat *)buf);
361 return res;
362# else
363 return internal_syscall(SYSCALL(fstat)5, fd, (uptr)buf);
2
←
Calling 'internal_syscall<int, unsigned long>'
→
4
←
Returning from 'internal_syscall<int, unsigned long>'
→
5
←
Returning without writing to 'buf->st_size'
→
364# endif
365#else
366 struct stat64 buf64;
367 int res = internal_syscall(SYSCALL(fstat64)__NR_fstat64, fd, &buf64);
368 stat64_to_stat(&buf64, (struct stat *)buf);
369 return res;
370#endif
371}
372
373uptr internal_filesize(fd_t fd) {
374 struct stat st;
375 if (internal_fstat(fd, &st))
1
Calling 'internal_fstat'
→
6
←
Returning from 'internal_fstat'
→
7
←
Assuming the condition is false
→
8
←
Taking false branch
→
376 return -1;
377 return (uptr)st.st_size;
9
←
Undefined or garbage value returned to caller
378}
379
380uptr internal_dup(int oldfd) {
381 return internal_syscall(SYSCALL(dup)32, oldfd);
382}
383
384uptr internal_dup2(int oldfd, int newfd) {
385#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
386 return internal_syscall(SYSCALL(dup3)292, oldfd, newfd, 0);
387#else
388 return internal_syscall(SYSCALL(dup2)33, oldfd, newfd);
389#endif
390}
391
392uptr internal_readlink(const char *path, char *buf, uptr bufsize) {
393#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
394 return internal_syscall(SYSCALL(readlinkat)267, AT_FDCWD-100, (uptr)path, (uptr)buf,
395 bufsize);
396#else
397 return internal_syscall(SYSCALL(readlink)89, (uptr)path, (uptr)buf, bufsize);
398#endif
399}
400
401uptr internal_unlink(const char *path) {
402#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
403 return internal_syscall(SYSCALL(unlinkat)263, AT_FDCWD-100, (uptr)path, 0);
404#else
405 return internal_syscall(SYSCALL(unlink)87, (uptr)path);
406#endif
407}
408
409uptr internal_rename(const char *oldpath, const char *newpath) {
410#if defined(__riscv)
411 return internal_syscall(SYSCALL(renameat2)316, AT_FDCWD-100, (uptr)oldpath, AT_FDCWD-100,
412 (uptr)newpath, 0);
413#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
414 return internal_syscall(SYSCALL(renameat)264, AT_FDCWD-100, (uptr)oldpath, AT_FDCWD-100,
415 (uptr)newpath);
416#else
417 return internal_syscall(SYSCALL(rename)82, (uptr)oldpath, (uptr)newpath);
418#endif
419}
420
421uptr internal_sched_yield() {
422 return internal_syscall(SYSCALL(sched_yield)24);
423}
424
425unsigned int internal_sleep(unsigned int seconds) {
426 struct timespec ts;
427 ts.tv_sec = seconds;
428 ts.tv_nsec = 0;
429 int res = internal_syscall(SYSCALL(nanosleep)35, &ts, &ts);
430 if (res) return ts.tv_sec;
431 return 0;
432}
433
434uptr internal_execve(const char *filename, char *const argv[],
435 char *const envp[]) {
436 return internal_syscall(SYSCALL(execve)59, (uptr)filename, (uptr)argv,
437 (uptr)envp);
438}
439#endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD
440
441#if !SANITIZER_NETBSD0
442void internal__exit(int exitcode) {
443#if SANITIZER_FREEBSD0 || SANITIZER_SOLARIS0
444 internal_syscall(SYSCALL(exit)60, exitcode);
445#else
446 internal_syscall(SYSCALL(exit_group)231, exitcode);
447#endif
448 Die(); // Unreachable.
449}
450#endif // !SANITIZER_NETBSD
451
452// ----------------- sanitizer_common.h
453bool FileExists(const char *filename) {
454 if (ShouldMockFailureToOpen(filename))
455 return false;
456 struct stat st;
457#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
458 if (internal_syscall(SYSCALL(newfstatat)262, AT_FDCWD-100, filename, &st, 0))
459#else
460 if (internal_stat(filename, &st))
461#endif
462 return false;
463 // Sanity check: filename is a regular file.
464 return S_ISREG(st.st_mode)((((st.st_mode)) & 0170000) == (0100000));
465}
466
467#if !SANITIZER_NETBSD0
468tid_t GetTid() {
469#if SANITIZER_FREEBSD0
470 long Tid;
471 thr_self(&Tid);
472 return Tid;
473#elif SANITIZER_SOLARIS0
474 return thr_self();
475#else
476 return internal_syscall(SYSCALL(gettid)186);
477#endif
478}
479
480int TgKill(pid_t pid, tid_t tid, int sig) {
481#if SANITIZER_LINUX1
482 return internal_syscall(SYSCALL(tgkill)234, pid, tid, sig);
483#elif SANITIZER_FREEBSD0
484 return internal_syscall(SYSCALL(thr_kill2)__NR_thr_kill2, pid, tid, sig);
485#elif SANITIZER_SOLARIS0
486 (void)pid;
487 return thr_kill(tid, sig);
488#endif
489}
490#endif
491
492#if !SANITIZER_SOLARIS0 && !SANITIZER_NETBSD0
493u64 NanoTime() {
494#if SANITIZER_FREEBSD0
495 timeval tv;
496#else
497 kernel_timeval tv;
498#endif
499 internal_memset(&tv, 0, sizeof(tv));
500 internal_syscall(SYSCALL(gettimeofday)96, &tv, 0);
501 return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000;
502}
503
504uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) {
505 return internal_syscall(SYSCALL(clock_gettime)228, clk_id, tp);
506}
507#endif // !SANITIZER_SOLARIS && !SANITIZER_NETBSD
508
509// Like getenv, but reads env directly from /proc (on Linux) or parses the
510// 'environ' array (on some others) and does not use libc. This function
511// should be called first inside __asan_init.
512const char *GetEnv(const char *name) {
513#if SANITIZER_FREEBSD0 || SANITIZER_NETBSD0 || SANITIZER_SOLARIS0
514 if (::environ != 0) {
515 uptr NameLen = internal_strlen(name);
516 for (char **Env = ::environ; *Env != 0; Env++) {
517 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=')
518 return (*Env) + NameLen + 1;
519 }
520 }
521 return 0; // Not found.
522#elif SANITIZER_LINUX1
523 static char *environ;
524 static uptr len;
525 static bool inited;
526 if (!inited) {
527 inited = true;
528 uptr environ_size;
529 if (!ReadFileToBuffer("/proc/self/environ", &environ, &environ_size, &len))
530 environ = nullptr;
531 }
532 if (!environ || len == 0) return nullptr;
533 uptr namelen = internal_strlen(name);
534 const char *p = environ;
535 while (*p != '\0') { // will happen at the \0\0 that terminates the buffer
536 // proc file has the format NAME=value\0NAME=value\0NAME=value\0...
537 const char* endp =
538 (char*)internal_memchr(p, '\0', len - (p - environ));
539 if (!endp) // this entry isn't NUL terminated
540 return nullptr;
541 else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=') // Match.
542 return p + namelen + 1; // point after =
543 p = endp + 1;
544 }
545 return nullptr; // Not found.
546#else
547#error "Unsupported platform"
548#endif
549}
550
551#if !SANITIZER_FREEBSD0 && !SANITIZER_NETBSD0 && !SANITIZER_GO0
552extern "C" {
553SANITIZER_WEAK_ATTRIBUTE__attribute__((weak)) extern void *__libc_stack_end;
554}
555#endif
556
557#if !SANITIZER_FREEBSD0 && !SANITIZER_NETBSD0
558static void ReadNullSepFileToArray(const char *path, char ***arr,
559 int arr_size) {
560 char *buff;
561 uptr buff_size;
562 uptr buff_len;
563 *arr = (char **)MmapOrDie(arr_size * sizeof(char *), "NullSepFileArray");
564 if (!ReadFileToBuffer(path, &buff, &buff_size, &buff_len, 1024 * 1024)) {
565 (*arr)[0] = nullptr;
566 return;
567 }
568 (*arr)[0] = buff;
569 int count, i;
570 for (count = 1, i = 1; ; i++) {
571 if (buff[i] == 0) {
572 if (buff[i+1] == 0) break;
573 (*arr)[count] = &buff[i+1];
574 CHECK_LE(count, arr_size - 1)do { __sanitizer::u64 v1 = (__sanitizer::u64)((count)); __sanitizer
::u64 v2 = (__sanitizer::u64)((arr_size - 1)); if (__builtin_expect
(!!(!(v1 <= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 574, "(" "(count)" ") " "<=" " (" "(arr_size - 1)" ")", v1
, v2); } while (false); // FIXME: make this more flexible.
575 count++;
576 }
577 }
578 (*arr)[count] = nullptr;
579}
580#endif
581
582static void GetArgsAndEnv(char ***argv, char ***envp) {
583#if SANITIZER_FREEBSD0
584 // On FreeBSD, retrieving the argument and environment arrays is done via the
585 // kern.ps_strings sysctl, which returns a pointer to a structure containing
586 // this information. See also <sys/exec.h>.
587 ps_strings *pss;
588 uptr sz = sizeof(pss);
589 if (internal_sysctlbyname("kern.ps_strings", &pss, &sz, NULL__null, 0) == -1) {
590 Printf("sysctl kern.ps_strings failed\n");
591 Die();
592 }
593 *argv = pss->ps_argvstr;
594 *envp = pss->ps_envstr;
595#elif SANITIZER_NETBSD0
596 *argv = __ps_strings->ps_argvstr;
597 *envp = __ps_strings->ps_envstr;
598#else // SANITIZER_FREEBSD
599#if !SANITIZER_GO0
600 if (&__libc_stack_end) {
601 uptr* stack_end = (uptr*)__libc_stack_end;
602 // Normally argc can be obtained from *stack_end, however, on ARM glibc's
603 // _start clobbers it:
604 // https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/arm/start.S;hb=refs/heads/release/2.31/master#l75
605 // Do not special-case ARM and infer argc from argv everywhere.
606 int argc = 0;
607 while (stack_end[argc + 1]) argc++;
608 *argv = (char**)(stack_end + 1);
609 *envp = (char**)(stack_end + argc + 2);
610 } else {
611#endif // !SANITIZER_GO
612 static const int kMaxArgv = 2000, kMaxEnvp = 2000;
613 ReadNullSepFileToArray("/proc/self/cmdline", argv, kMaxArgv);
614 ReadNullSepFileToArray("/proc/self/environ", envp, kMaxEnvp);
615#if !SANITIZER_GO0
616 }
617#endif // !SANITIZER_GO
618#endif // SANITIZER_FREEBSD
619}
620
621char **GetArgv() {
622 char **argv, **envp;
623 GetArgsAndEnv(&argv, &envp);
624 return argv;
625}
626
627char **GetEnviron() {
628 char **argv, **envp;
629 GetArgsAndEnv(&argv, &envp);
630 return envp;
631}
632
633#if !SANITIZER_SOLARIS0
634enum MutexState {
635 MtxUnlocked = 0,
636 MtxLocked = 1,
637 MtxSleeping = 2
638};
639
640BlockingMutex::BlockingMutex() {
641 internal_memset(this, 0, sizeof(*this));
642}
643
644void BlockingMutex::Lock() {
645 CHECK_EQ(owner_, 0)do { __sanitizer::u64 v1 = (__sanitizer::u64)((owner_)); __sanitizer
::u64 v2 = (__sanitizer::u64)((0)); if (__builtin_expect(!!(!
(v1 == v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 645, "(" "(owner_)" ") " "==" " (" "(0)" ")", v1, v2); } while
(false);
646 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_);
647 if (atomic_exchange(m, MtxLocked, memory_order_acquire) == MtxUnlocked)
648 return;
649 while (atomic_exchange(m, MtxSleeping, memory_order_acquire) != MtxUnlocked) {
650#if SANITIZER_FREEBSD0
651 _umtx_op(m, UMTX_OP_WAIT_UINT, MtxSleeping, 0, 0);
652#elif SANITIZER_NETBSD0
653 sched_yield(); /* No userspace futex-like synchronization */
654#else
655 internal_syscall(SYSCALL(futex)202, (uptr)m, FUTEX_WAIT_PRIVATE, MtxSleeping,
656 0, 0, 0);
657#endif
658 }
659}
660
661void BlockingMutex::Unlock() {
662 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_);
663 u32 v = atomic_exchange(m, MtxUnlocked, memory_order_release);
664 CHECK_NE(v, MtxUnlocked)do { __sanitizer::u64 v1 = (__sanitizer::u64)((v)); __sanitizer
::u64 v2 = (__sanitizer::u64)((MtxUnlocked)); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 664, "(" "(v)" ") " "!=" " (" "(MtxUnlocked)" ")", v1, v2);
} while (false);
665 if (v == MtxSleeping) {
666#if SANITIZER_FREEBSD0
667 _umtx_op(m, UMTX_OP_WAKE, 1, 0, 0);
668#elif SANITIZER_NETBSD0
669 /* No userspace futex-like synchronization */
670#else
671 internal_syscall(SYSCALL(futex)202, (uptr)m, FUTEX_WAKE_PRIVATE, 1, 0, 0, 0);
672#endif
673 }
674}
675
676void BlockingMutex::CheckLocked() {
677 atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_);
678 CHECK_NE(MtxUnlocked, atomic_load(m, memory_order_relaxed))do { __sanitizer::u64 v1 = (__sanitizer::u64)((MtxUnlocked));
__sanitizer::u64 v2 = (__sanitizer::u64)((atomic_load(m, memory_order_relaxed
))); if (__builtin_expect(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed
("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 678, "(" "(MtxUnlocked)" ") " "!=" " (" "(atomic_load(m, memory_order_relaxed))"
")", v1, v2); } while (false);
679}
680#endif // !SANITIZER_SOLARIS
681
682// ----------------- sanitizer_linux.h
683// The actual size of this structure is specified by d_reclen.
684// Note that getdents64 uses a different structure format. We only provide the
685// 32-bit syscall here.
686#if SANITIZER_NETBSD0
687// Not used
688#else
689struct linux_dirent {
690#if SANITIZER_X320 || defined(__aarch64__) || SANITIZER_RISCV640
691 u64 d_ino;
692 u64 d_off;
693#else
694 unsigned long d_ino;
695 unsigned long d_off;
696#endif
697 unsigned short d_reclen;
698#if defined(__aarch64__) || SANITIZER_RISCV640
699 unsigned char d_type;
700#endif
701 char d_name[256];
702};
703#endif
704
705#if !SANITIZER_SOLARIS0 && !SANITIZER_NETBSD0
706// Syscall wrappers.
707uptr internal_ptrace(int request, int pid, void *addr, void *data) {
708 return internal_syscall(SYSCALL(ptrace)101, request, pid, (uptr)addr,
709 (uptr)data);
710}
711
712uptr internal_waitpid(int pid, int *status, int options) {
713 return internal_syscall(SYSCALL(wait4)61, pid, (uptr)status, options,
714 0 /* rusage */);
715}
716
717uptr internal_getpid() {
718 return internal_syscall(SYSCALL(getpid)39);
719}
720
721uptr internal_getppid() {
722 return internal_syscall(SYSCALL(getppid)110);
723}
724
725int internal_dlinfo(void *handle, int request, void *p) {
726#if SANITIZER_FREEBSD0
727 return dlinfo(handle, request, p);
728#else
729 UNIMPLEMENTED()do { do { __sanitizer::u64 v1 = (__sanitizer::u64)((0 &&
"unimplemented")); __sanitizer::u64 v2 = (__sanitizer::u64)(
0); if (__builtin_expect(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed
("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 729, "(" "(0 && \"unimplemented\")" ") " "!=" " (" "0"
")", v1, v2); } while (false); Die(); } while (0);
730#endif
731}
732
733uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) {
734#if SANITIZER_FREEBSD0
735 return internal_syscall(SYSCALL(getdirentries)__NR_getdirentries, fd, (uptr)dirp, count, NULL__null);
736#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
737 return internal_syscall(SYSCALL(getdents64)217, fd, (uptr)dirp, count);
738#else
739 return internal_syscall(SYSCALL(getdents)78, fd, (uptr)dirp, count);
740#endif
741}
742
743uptr internal_lseek(fd_t fd, OFF_T offset, int whence) {
744 return internal_syscall(SYSCALL(lseek)8, fd, offset, whence);
745}
746
747#if SANITIZER_LINUX1
748uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) {
749 return internal_syscall(SYSCALL(prctl)157, option, arg2, arg3, arg4, arg5);
750}
751#endif
752
753uptr internal_sigaltstack(const void *ss, void *oss) {
754 return internal_syscall(SYSCALL(sigaltstack)131, (uptr)ss, (uptr)oss);
755}
756
757int internal_fork() {
758#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS0
759 return internal_syscall(SYSCALL(clone)56, SIGCHLD17, 0);
760#else
761 return internal_syscall(SYSCALL(fork)57);
762#endif
763}
764
765#if SANITIZER_FREEBSD0
766int internal_sysctl(const int *name, unsigned int namelen, void *oldp,
767 uptr *oldlenp, const void *newp, uptr newlen) {
768 return internal_syscall(SYSCALL(__sysctl)__NR___sysctl, name, namelen, oldp,
769 (size_t *)oldlenp, newp, (size_t)newlen);
770}
771
772int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp,
773 const void *newp, uptr newlen) {
774 // Note: this function can be called during startup, so we need to avoid
775 // calling any interceptable functions. On FreeBSD >= 1300045 sysctlbyname()
776 // is a real syscall, but for older versions it calls sysctlnametomib()
777 // followed by sysctl(). To avoid calling the intercepted version and
778 // asserting if this happens during startup, call the real sysctlnametomib()
779 // followed by internal_sysctl() if the syscall is not available.
780#ifdef SYS___sysctlbyname
781 return internal_syscall(SYSCALL(__sysctlbyname)__NR___sysctlbyname, sname,
782 internal_strlen(sname), oldp, (size_t *)oldlenp, newp,
783 (size_t)newlen);
784#else
785 static decltype(sysctlnametomib) *real_sysctlnametomib = nullptr;
786 if (!real_sysctlnametomib)
787 real_sysctlnametomib =
788 (decltype(sysctlnametomib) *)dlsym(RTLD_NEXT((void *) -1l), "sysctlnametomib");
789 CHECK(real_sysctlnametomib)do { __sanitizer::u64 v1 = (__sanitizer::u64)((real_sysctlnametomib
)); __sanitizer::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 789, "(" "(real_sysctlnametomib)" ") " "!=" " (" "0" ")", v1
, v2); } while (false);
790
791 int oid[CTL_MAXNAME];
792 size_t len = CTL_MAXNAME;
793 if (real_sysctlnametomib(sname, oid, &len) == -1)
794 return (-1);
795 return internal_sysctl(oid, len, oldp, oldlenp, newp, newlen);
796#endif
797}
798#endif
799
800#if SANITIZER_LINUX1
801#define SA_RESTORER0x04000000 0x04000000
802// Doesn't set sa_restorer if the caller did not set it, so use with caution
803//(see below).
804int internal_sigaction_norestorer(int signum, const void *act, void *oldact) {
805 __sanitizer_kernel_sigaction_t k_act, k_oldact;
806 internal_memset(&k_act, 0, sizeof(__sanitizer_kernel_sigaction_t));
807 internal_memset(&k_oldact, 0, sizeof(__sanitizer_kernel_sigaction_t));
808 const __sanitizer_sigaction *u_act = (const __sanitizer_sigaction *)act;
809 __sanitizer_sigaction *u_oldact = (__sanitizer_sigaction *)oldact;
810 if (u_act) {
811 k_act.handler = u_act->handler;
812 k_act.sigaction = u_act->sigaction;
813 internal_memcpy(&k_act.sa_mask, &u_act->sa_mask,
814 sizeof(__sanitizer_kernel_sigset_t));
815 // Without SA_RESTORER kernel ignores the calls (probably returns EINVAL).
816 k_act.sa_flags = u_act->sa_flags | SA_RESTORER0x04000000;
817 // FIXME: most often sa_restorer is unset, however the kernel requires it
818 // to point to a valid signal restorer that calls the rt_sigreturn syscall.
819 // If sa_restorer passed to the kernel is NULL, the program may crash upon
820 // signal delivery or fail to unwind the stack in the signal handler.
821 // libc implementation of sigaction() passes its own restorer to
822 // rt_sigaction, so we need to do the same (we'll need to reimplement the
823 // restorers; for x86_64 the restorer address can be obtained from
824 // oldact->sa_restorer upon a call to sigaction(xxx, NULL, oldact).
825#if !SANITIZER_ANDROID0 || !SANITIZER_MIPS320
826 k_act.sa_restorer = u_act->sa_restorer;
827#endif
828 }
829
830 uptr result = internal_syscall(SYSCALL(rt_sigaction)13, (uptr)signum,
831 (uptr)(u_act ? &k_act : nullptr),
832 (uptr)(u_oldact ? &k_oldact : nullptr),
833 (uptr)sizeof(__sanitizer_kernel_sigset_t));
834
835 if ((result == 0) && u_oldact) {
836 u_oldact->handler = k_oldact.handler;
837 u_oldact->sigaction = k_oldact.sigaction;
838 internal_memcpy(&u_oldact->sa_mask, &k_oldact.sa_mask,
839 sizeof(__sanitizer_kernel_sigset_t));
840 u_oldact->sa_flags = k_oldact.sa_flags;
841#if !SANITIZER_ANDROID0 || !SANITIZER_MIPS320
842 u_oldact->sa_restorer = k_oldact.sa_restorer;
843#endif
844 }
845 return result;
846}
847#endif // SANITIZER_LINUX
848
849uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
850 __sanitizer_sigset_t *oldset) {
851#if SANITIZER_FREEBSD0
852 return internal_syscall(SYSCALL(sigprocmask)__NR_sigprocmask, how, set, oldset);
853#else
854 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set;
855 __sanitizer_kernel_sigset_t *k_oldset = (__sanitizer_kernel_sigset_t *)oldset;
856 return internal_syscall(SYSCALL(rt_sigprocmask)14, (uptr)how, (uptr)k_set,
857 (uptr)k_oldset, sizeof(__sanitizer_kernel_sigset_t));
858#endif
859}
860
861void internal_sigfillset(__sanitizer_sigset_t *set) {
862 internal_memset(set, 0xff, sizeof(*set));
863}
864
865void internal_sigemptyset(__sanitizer_sigset_t *set) {
866 internal_memset(set, 0, sizeof(*set));
867}
868
869#if SANITIZER_LINUX1
870void internal_sigdelset(__sanitizer_sigset_t *set, int signum) {
871 signum -= 1;
872 CHECK_GE(signum, 0)do { __sanitizer::u64 v1 = (__sanitizer::u64)((signum)); __sanitizer
::u64 v2 = (__sanitizer::u64)((0)); if (__builtin_expect(!!(!
(v1 >= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 872, "(" "(signum)" ") " ">=" " (" "(0)" ")", v1, v2); }
while (false);
873 CHECK_LT(signum, sizeof(*set) * 8)do { __sanitizer::u64 v1 = (__sanitizer::u64)((signum)); __sanitizer
::u64 v2 = (__sanitizer::u64)((sizeof(*set) * 8)); if (__builtin_expect
(!!(!(v1 < v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 873, "(" "(signum)" ") " "<" " (" "(sizeof(*set) * 8)" ")"
, v1, v2); } while (false);
874 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set;
875 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8);
876 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8);
877 k_set->sig[idx] &= ~(1 << bit);
878}
879
880bool internal_sigismember(__sanitizer_sigset_t *set, int signum) {
881 signum -= 1;
882 CHECK_GE(signum, 0)do { __sanitizer::u64 v1 = (__sanitizer::u64)((signum)); __sanitizer
::u64 v2 = (__sanitizer::u64)((0)); if (__builtin_expect(!!(!
(v1 >= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 882, "(" "(signum)" ") " ">=" " (" "(0)" ")", v1, v2); }
while (false);
883 CHECK_LT(signum, sizeof(*set) * 8)do { __sanitizer::u64 v1 = (__sanitizer::u64)((signum)); __sanitizer
::u64 v2 = (__sanitizer::u64)((sizeof(*set) * 8)); if (__builtin_expect
(!!(!(v1 < v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 883, "(" "(signum)" ") " "<" " (" "(sizeof(*set) * 8)" ")"
, v1, v2); } while (false);
884 __sanitizer_kernel_sigset_t *k_set = (__sanitizer_kernel_sigset_t *)set;
885 const uptr idx = signum / (sizeof(k_set->sig[0]) * 8);
886 const uptr bit = signum % (sizeof(k_set->sig[0]) * 8);
887 return k_set->sig[idx] & (1 << bit);
888}
889#elif SANITIZER_FREEBSD0
890void internal_sigdelset(__sanitizer_sigset_t *set, int signum) {
891 sigset_t *rset = reinterpret_cast<sigset_t *>(set);
892 sigdelset(rset, signum);
893}
894
895bool internal_sigismember(__sanitizer_sigset_t *set, int signum) {
896 sigset_t *rset = reinterpret_cast<sigset_t *>(set);
897 return sigismember(rset, signum);
898}
899#endif
900#endif // !SANITIZER_SOLARIS
901
902#if !SANITIZER_NETBSD0
903// ThreadLister implementation.
904ThreadLister::ThreadLister(pid_t pid) : pid_(pid), buffer_(4096) {
905 char task_directory_path[80];
906 internal_snprintf(task_directory_path, sizeof(task_directory_path),
907 "/proc/%d/task/", pid);
908 descriptor_ = internal_open(task_directory_path, O_RDONLY00 | O_DIRECTORY0200000);
909 if (internal_iserror(descriptor_)) {
910 Report("Can't open /proc/%d/task for reading.\n", pid);
911 }
912}
913
914ThreadLister::Result ThreadLister::ListThreads(
915 InternalMmapVector<tid_t> *threads) {
916 if (internal_iserror(descriptor_))
917 return Error;
918 internal_lseek(descriptor_, 0, SEEK_SET0);
919 threads->clear();
920
921 Result result = Ok;
922 for (bool first_read = true;; first_read = false) {
923 // Resize to max capacity if it was downsized by IsAlive.
924 buffer_.resize(buffer_.capacity());
925 CHECK_GE(buffer_.size(), 4096)do { __sanitizer::u64 v1 = (__sanitizer::u64)((buffer_.size()
)); __sanitizer::u64 v2 = (__sanitizer::u64)((4096)); if (__builtin_expect
(!!(!(v1 >= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 925, "(" "(buffer_.size())" ") " ">=" " (" "(4096)" ")",
v1, v2); } while (false);
926 uptr read = internal_getdents(
927 descriptor_, (struct linux_dirent *)buffer_.data(), buffer_.size());
928 if (!read)
929 return result;
930 if (internal_iserror(read)) {
931 Report("Can't read directory entries from /proc/%d/task.\n", pid_);
932 return Error;
933 }
934
935 for (uptr begin = (uptr)buffer_.data(), end = begin + read; begin < end;) {
936 struct linux_dirent *entry = (struct linux_dirent *)begin;
937 begin += entry->d_reclen;
938 if (entry->d_ino == 1) {
939 // Inode 1 is for bad blocks and also can be a reason for early return.
940 // Should be emitted if kernel tried to output terminating thread.
941 // See proc_task_readdir implementation in Linux.
942 result = Incomplete;
943 }
944 if (entry->d_ino && *entry->d_name >= '0' && *entry->d_name <= '9')
945 threads->push_back(internal_atoll(entry->d_name));
946 }
947
948 // Now we are going to detect short-read or early EOF. In such cases Linux
949 // can return inconsistent list with missing alive threads.
950 // Code will just remember that the list can be incomplete but it will
951 // continue reads to return as much as possible.
952 if (!first_read) {
953 // The first one was a short-read by definition.
954 result = Incomplete;
955 } else if (read > buffer_.size() - 1024) {
956 // Read was close to the buffer size. So double the size and assume the
957 // worst.
958 buffer_.resize(buffer_.size() * 2);
959 result = Incomplete;
960 } else if (!threads->empty() && !IsAlive(threads->back())) {
961 // Maybe Linux early returned from read on terminated thread (!pid_alive)
962 // and failed to restore read position.
963 // See next_tid and proc_task_instantiate in Linux.
964 result = Incomplete;
965 }
966 }
967}
968
969bool ThreadLister::IsAlive(int tid) {
970 // /proc/%d/task/%d/status uses same call to detect alive threads as
971 // proc_task_readdir. See task_state implementation in Linux.
972 char path[80];
973 internal_snprintf(path, sizeof(path), "/proc/%d/task/%d/status", pid_, tid);
974 if (!ReadFileToVector(path, &buffer_) || buffer_.empty())
975 return false;
976 buffer_.push_back(0);
977 static const char kPrefix[] = "\nPPid:";
978 const char *field = internal_strstr(buffer_.data(), kPrefix);
979 if (!field)
980 return false;
981 field += internal_strlen(kPrefix);
982 return (int)internal_atoll(field) != 0;
983}
984
985ThreadLister::~ThreadLister() {
986 if (!internal_iserror(descriptor_))
987 internal_close(descriptor_);
988}
989#endif
990
991#if SANITIZER_WORDSIZE64 == 32
992// Take care of unusable kernel area in top gigabyte.
993static uptr GetKernelAreaSize() {
994#if SANITIZER_LINUX1 && !SANITIZER_X320
995 const uptr gbyte = 1UL << 30;
996
997 // Firstly check if there are writable segments
998 // mapped to top gigabyte (e.g. stack).
999 MemoryMappingLayout proc_maps(/*cache_enabled*/true);
1000 if (proc_maps.Error())
1001 return 0;
1002 MemoryMappedSegment segment;
1003 while (proc_maps.Next(&segment)) {
1004 if ((segment.end >= 3 * gbyte) && segment.IsWritable()) return 0;
1005 }
1006
1007#if !SANITIZER_ANDROID0
1008 // Even if nothing is mapped, top Gb may still be accessible
1009 // if we are running on 64-bit kernel.
1010 // Uname may report misleading results if personality type
1011 // is modified (e.g. under schroot) so check this as well.
1012 struct utsname uname_info;
1013 int pers = personality(0xffffffffUL);
1014 if (!(pers & PER_MASK) && internal_uname(&uname_info) == 0 &&
1015 internal_strstr(uname_info.machine, "64"))
1016 return 0;
1017#endif // SANITIZER_ANDROID
1018
1019 // Top gigabyte is reserved for kernel.
1020 return gbyte;
1021#else
1022 return 0;
1023#endif // SANITIZER_LINUX && !SANITIZER_X32
1024}
1025#endif // SANITIZER_WORDSIZE == 32
1026
1027uptr GetMaxVirtualAddress() {
1028#if SANITIZER_NETBSD0 && defined(__x86_64__1)
1029 return 0x7f7ffffff000ULL; // (0x00007f8000000000 - PAGE_SIZE)
1030#elif SANITIZER_WORDSIZE64 == 64
1031# if defined(__powerpc64__) || defined(__aarch64__)
1032 // On PowerPC64 we have two different address space layouts: 44- and 46-bit.
1033 // We somehow need to figure out which one we are using now and choose
1034 // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL.
1035 // Note that with 'ulimit -s unlimited' the stack is moved away from the top
1036 // of the address space, so simply checking the stack address is not enough.
1037 // This should (does) work for both PowerPC64 Endian modes.
1038 // Similarly, aarch64 has multiple address space layouts: 39, 42 and 47-bit.
1039 return (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()(__sanitizer::uptr) __builtin_frame_address(0)) + 1)) - 1;
1040#elif SANITIZER_RISCV640
1041 return (1ULL << 38) - 1;
1042# elif defined(__mips64)
1043 return (1ULL << 40) - 1; // 0x000000ffffffffffUL;
1044# elif defined(__s390x__)
1045 return (1ULL << 53) - 1; // 0x001fffffffffffffUL;
1046#elif defined(__sparc__)
1047 return ~(uptr)0;
1048# else
1049 return (1ULL << 47) - 1; // 0x00007fffffffffffUL;
1050# endif
1051#else // SANITIZER_WORDSIZE == 32
1052# if defined(__s390__)
1053 return (1ULL << 31) - 1; // 0x7fffffff;
1054# else
1055 return (1ULL << 32) - 1; // 0xffffffff;
1056# endif
1057#endif // SANITIZER_WORDSIZE
1058}
1059
1060uptr GetMaxUserVirtualAddress() {
1061 uptr addr = GetMaxVirtualAddress();
1062#if SANITIZER_WORDSIZE64 == 32 && !defined(__s390__)
1063 if (!common_flags()->full_address_space)
1064 addr -= GetKernelAreaSize();
1065 CHECK_LT(reinterpret_cast<uptr>(&addr), addr)do { __sanitizer::u64 v1 = (__sanitizer::u64)((reinterpret_cast
<uptr>(&addr))); __sanitizer::u64 v2 = (__sanitizer
::u64)((addr)); if (__builtin_expect(!!(!(v1 < v2)), 0)) __sanitizer
::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1065, "(" "(reinterpret_cast<uptr>(&addr))" ") " "<"
" (" "(addr)" ")", v1, v2); } while (false);
1066#endif
1067 return addr;
1068}
1069
1070#if !SANITIZER_ANDROID0
1071uptr GetPageSize() {
1072#if SANITIZER_LINUX1 && (defined(__x86_64__1) || defined(__i386__)) && \
1073 defined(EXEC_PAGESIZE4096)
1074 return EXEC_PAGESIZE4096;
1075#elif SANITIZER_FREEBSD0 || SANITIZER_NETBSD0
1076// Use sysctl as sysconf can trigger interceptors internally.
1077 int pz = 0;
1078 uptr pzl = sizeof(pz);
1079 int mib[2] = {CTL_HW, HW_PAGESIZE};
1080 int rv = internal_sysctl(mib, 2, &pz, &pzl, nullptr, 0);
1081 CHECK_EQ(rv, 0)do { __sanitizer::u64 v1 = (__sanitizer::u64)((rv)); __sanitizer
::u64 v2 = (__sanitizer::u64)((0)); if (__builtin_expect(!!(!
(v1 == v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1081, "(" "(rv)" ") " "==" " (" "(0)" ")", v1, v2); } while
(false);
1082 return (uptr)pz;
1083#elif SANITIZER_USE_GETAUXVAL1
1084 return getauxval(AT_PAGESZ6);
1085#else
1086 return sysconf(_SC_PAGESIZE_SC_PAGESIZE); // EXEC_PAGESIZE may not be trustworthy.
1087#endif
1088}
1089#endif // !SANITIZER_ANDROID
1090
1091uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) {
1092#if SANITIZER_SOLARIS0
1093 const char *default_module_name = getexecname();
1094 CHECK_NE(default_module_name, NULL)do { __sanitizer::u64 v1 = (__sanitizer::u64)((default_module_name
)); __sanitizer::u64 v2 = (__sanitizer::u64)((__null)); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1094, "(" "(default_module_name)" ") " "!=" " (" "(__null)"
")", v1, v2); } while (false);
1095 return internal_snprintf(buf, buf_len, "%s", default_module_name);
1096#else
1097#if SANITIZER_FREEBSD0 || SANITIZER_NETBSD0
1098#if SANITIZER_FREEBSD0
1099 const int Mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1};
1100#else
1101 const int Mib[4] = {CTL_KERN, KERN_PROC_ARGS, -1, KERN_PROC_PATHNAME};
1102#endif
1103 const char *default_module_name = "kern.proc.pathname";
1104 uptr Size = buf_len;
1105 bool IsErr =
1106 (internal_sysctl(Mib, ARRAY_SIZE(Mib)(sizeof(Mib)/sizeof((Mib)[0])), buf, &Size, NULL__null, 0) != 0);
1107 int readlink_error = IsErr ? errno(*__errno_location ()) : 0;
1108 uptr module_name_len = Size;
1109#else
1110 const char *default_module_name = "/proc/self/exe";
1111 uptr module_name_len = internal_readlink(
1112 default_module_name, buf, buf_len);
1113 int readlink_error;
1114 bool IsErr = internal_iserror(module_name_len, &readlink_error);
1115#endif // SANITIZER_SOLARIS
1116 if (IsErr) {
1117 // We can't read binary name for some reason, assume it's unknown.
1118 Report("WARNING: reading executable name failed with errno %d, "
1119 "some stack frames may not be symbolized\n", readlink_error);
1120 module_name_len = internal_snprintf(buf, buf_len, "%s",
1121 default_module_name);
1122 CHECK_LT(module_name_len, buf_len)do { __sanitizer::u64 v1 = (__sanitizer::u64)((module_name_len
)); __sanitizer::u64 v2 = (__sanitizer::u64)((buf_len)); if (
__builtin_expect(!!(!(v1 < v2)), 0)) __sanitizer::CheckFailed
("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1122, "(" "(module_name_len)" ") " "<" " (" "(buf_len)" ")"
, v1, v2); } while (false);
1123 }
1124 return module_name_len;
1125#endif
1126}
1127
1128uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) {
1129#if SANITIZER_LINUX1
1130 char *tmpbuf;
1131 uptr tmpsize;
1132 uptr tmplen;
1133 if (ReadFileToBuffer("/proc/self/cmdline", &tmpbuf, &tmpsize, &tmplen,
1134 1024 * 1024)) {
1135 internal_strncpy(buf, tmpbuf, buf_len);
1136 UnmapOrDie(tmpbuf, tmpsize);
1137 return internal_strlen(buf);
1138 }
1139#endif
1140 return ReadBinaryName(buf, buf_len);
1141}
1142
1143// Match full names of the form /path/to/base_name{-,.}*
1144bool LibraryNameIs(const char *full_name, const char *base_name) {
1145 const char *name = full_name;
1146 // Strip path.
1147 while (*name != '\0') name++;
1148 while (name > full_name && *name != '/') name--;
1149 if (*name == '/') name++;
1150 uptr base_name_length = internal_strlen(base_name);
1151 if (internal_strncmp(name, base_name, base_name_length)) return false;
1152 return (name[base_name_length] == '-' || name[base_name_length] == '.');
1153}
1154
1155#if !SANITIZER_ANDROID0
1156// Call cb for each region mapped by map.
1157void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) {
1158 CHECK_NE(map, nullptr)do { __sanitizer::u64 v1 = (__sanitizer::u64)((map)); __sanitizer
::u64 v2 = (__sanitizer::u64)((nullptr)); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1158, "(" "(map)" ") " "!=" " (" "(nullptr)" ")", v1, v2); }
while (false);
1159#if !SANITIZER_FREEBSD0
1160 typedef ElfW(Phdr)Elf64_Phdr Elf_Phdr;
1161 typedef ElfW(Ehdr)Elf64_Ehdr Elf_Ehdr;
1162#endif // !SANITIZER_FREEBSD
1163 char *base = (char *)map->l_addr;
1164 Elf_Ehdr *ehdr = (Elf_Ehdr *)base;
1165 char *phdrs = base + ehdr->e_phoff;
1166 char *phdrs_end = phdrs + ehdr->e_phnum * ehdr->e_phentsize;
1167
1168 // Find the segment with the minimum base so we can "relocate" the p_vaddr
1169 // fields. Typically ET_DYN objects (DSOs) have base of zero and ET_EXEC
1170 // objects have a non-zero base.
1171 uptr preferred_base = (uptr)-1;
1172 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) {
1173 Elf_Phdr *phdr = (Elf_Phdr *)iter;
1174 if (phdr->p_type == PT_LOAD1 && preferred_base > (uptr)phdr->p_vaddr)
1175 preferred_base = (uptr)phdr->p_vaddr;
1176 }
1177
1178 // Compute the delta from the real base to get a relocation delta.
1179 sptr delta = (uptr)base - preferred_base;
1180 // Now we can figure out what the loader really mapped.
1181 for (char *iter = phdrs; iter != phdrs_end; iter += ehdr->e_phentsize) {
1182 Elf_Phdr *phdr = (Elf_Phdr *)iter;
1183 if (phdr->p_type == PT_LOAD1) {
1184 uptr seg_start = phdr->p_vaddr + delta;
1185 uptr seg_end = seg_start + phdr->p_memsz;
1186 // None of these values are aligned. We consider the ragged edges of the
1187 // load command as defined, since they are mapped from the file.
1188 seg_start = RoundDownTo(seg_start, GetPageSizeCached());
1189 seg_end = RoundUpTo(seg_end, GetPageSizeCached());
1190 cb((void *)seg_start, seg_end - seg_start);
1191 }
1192 }
1193}
1194#endif
1195
1196#if defined(__x86_64__1) && SANITIZER_LINUX1
1197// We cannot use glibc's clone wrapper, because it messes with the child
1198// task's TLS. It writes the PID and TID of the child task to its thread
1199// descriptor, but in our case the child task shares the thread descriptor with
1200// the parent (because we don't know how to allocate a new thread
1201// descriptor to keep glibc happy). So the stock version of clone(), when
1202// used with CLONE_VM, would end up corrupting the parent's thread descriptor.
1203uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1204 int *parent_tidptr, void *newtls, int *child_tidptr) {
1205 long long res;
1206 if (!fn || !child_stack)
1207 return -EINVAL22;
1208 CHECK_EQ(0, (uptr)child_stack % 16)do { __sanitizer::u64 v1 = (__sanitizer::u64)((0)); __sanitizer
::u64 v2 = (__sanitizer::u64)(((uptr)child_stack % 16)); if (
__builtin_expect(!!(!(v1 == v2)), 0)) __sanitizer::CheckFailed
("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1208, "(" "(0)" ") " "==" " (" "((uptr)child_stack % 16)" ")"
, v1, v2); } while (false);
1209 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
1210 ((unsigned long long *)child_stack)[0] = (uptr)fn;
1211 ((unsigned long long *)child_stack)[1] = (uptr)arg;
1212 register void *r8 __asm__("r8") = newtls;
1213 register int *r10 __asm__("r10") = child_tidptr;
1214 __asm__ __volatile__(
1215 /* %rax = syscall(%rax = SYSCALL(clone),
1216 * %rdi = flags,
1217 * %rsi = child_stack,
1218 * %rdx = parent_tidptr,
1219 * %r8 = new_tls,
1220 * %r10 = child_tidptr)
1221 */
1222 "syscall\n"
1223
1224 /* if (%rax != 0)
1225 * return;
1226 */
1227 "testq %%rax,%%rax\n"
1228 "jnz 1f\n"
1229
1230 /* In the child. Terminate unwind chain. */
1231 // XXX: We should also terminate the CFI unwind chain
1232 // here. Unfortunately clang 3.2 doesn't support the
1233 // necessary CFI directives, so we skip that part.
1234 "xorq %%rbp,%%rbp\n"
1235
1236 /* Call "fn(arg)". */
1237 "popq %%rax\n"
1238 "popq %%rdi\n"
1239 "call *%%rax\n"
1240
1241 /* Call _exit(%rax). */
1242 "movq %%rax,%%rdi\n"
1243 "movq %2,%%rax\n"
1244 "syscall\n"
1245
1246 /* Return to parent. */
1247 "1:\n"
1248 : "=a" (res)
1249 : "a"(SYSCALL(clone)56), "i"(SYSCALL(exit)60),
1250 "S"(child_stack),
1251 "D"(flags),
1252 "d"(parent_tidptr),
1253 "r"(r8),
1254 "r"(r10)
1255 : "memory", "r11", "rcx");
1256 return res;
1257}
1258#elif defined(__mips__)
1259uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1260 int *parent_tidptr, void *newtls, int *child_tidptr) {
1261 long long res;
1262 if (!fn || !child_stack)
1263 return -EINVAL22;
1264 CHECK_EQ(0, (uptr)child_stack % 16)do { __sanitizer::u64 v1 = (__sanitizer::u64)((0)); __sanitizer
::u64 v2 = (__sanitizer::u64)(((uptr)child_stack % 16)); if (
__builtin_expect(!!(!(v1 == v2)), 0)) __sanitizer::CheckFailed
("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1264, "(" "(0)" ") " "==" " (" "((uptr)child_stack % 16)" ")"
, v1, v2); } while (false);
1265 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
1266 ((unsigned long long *)child_stack)[0] = (uptr)fn;
1267 ((unsigned long long *)child_stack)[1] = (uptr)arg;
1268 register void *a3 __asm__("$7") = newtls;
1269 register int *a4 __asm__("$8") = child_tidptr;
1270 // We don't have proper CFI directives here because it requires alot of code
1271 // for very marginal benefits.
1272 __asm__ __volatile__(
1273 /* $v0 = syscall($v0 = __NR_clone,
1274 * $a0 = flags,
1275 * $a1 = child_stack,
1276 * $a2 = parent_tidptr,
1277 * $a3 = new_tls,
1278 * $a4 = child_tidptr)
1279 */
1280 ".cprestore 16;\n"
1281 "move $4,%1;\n"
1282 "move $5,%2;\n"
1283 "move $6,%3;\n"
1284 "move $7,%4;\n"
1285 /* Store the fifth argument on stack
1286 * if we are using 32-bit abi.
1287 */
1288#if SANITIZER_WORDSIZE64 == 32
1289 "lw %5,16($29);\n"
1290#else
1291 "move $8,%5;\n"
1292#endif
1293 "li $2,%6;\n"
1294 "syscall;\n"
1295
1296 /* if ($v0 != 0)
1297 * return;
1298 */
1299 "bnez $2,1f;\n"
1300
1301 /* Call "fn(arg)". */
1302#if SANITIZER_WORDSIZE64 == 32
1303#ifdef __BIG_ENDIAN__
1304 "lw $25,4($29);\n"
1305 "lw $4,12($29);\n"
1306#else
1307 "lw $25,0($29);\n"
1308 "lw $4,8($29);\n"
1309#endif
1310#else
1311 "ld $25,0($29);\n"
1312 "ld $4,8($29);\n"
1313#endif
1314 "jal $25;\n"
1315
1316 /* Call _exit($v0). */
1317 "move $4,$2;\n"
1318 "li $2,%7;\n"
1319 "syscall;\n"
1320
1321 /* Return to parent. */
1322 "1:\n"
1323 : "=r" (res)
1324 : "r"(flags),
1325 "r"(child_stack),
1326 "r"(parent_tidptr),
1327 "r"(a3),
1328 "r"(a4),
1329 "i"(__NR_clone56),
1330 "i"(__NR_exit60)
1331 : "memory", "$29" );
1332 return res;
1333}
1334#elif SANITIZER_RISCV640
1335uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1336 int *parent_tidptr, void *newtls, int *child_tidptr) {
1337 long long res;
1338 if (!fn || !child_stack)
1339 return -EINVAL22;
1340 CHECK_EQ(0, (uptr)child_stack % 16)do { __sanitizer::u64 v1 = (__sanitizer::u64)((0)); __sanitizer
::u64 v2 = (__sanitizer::u64)(((uptr)child_stack % 16)); if (
__builtin_expect(!!(!(v1 == v2)), 0)) __sanitizer::CheckFailed
("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1340, "(" "(0)" ") " "==" " (" "((uptr)child_stack % 16)" ")"
, v1, v2); } while (false);
1341 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
1342 ((unsigned long long *)child_stack)[0] = (uptr)fn;
1343 ((unsigned long long *)child_stack)[1] = (uptr)arg;
1344
1345 register int (*__fn)(void *) __asm__("a0") = fn;
1346 register void *__stack __asm__("a1") = child_stack;
1347 register int __flags __asm__("a2") = flags;
1348 register void *__arg __asm__("a3") = arg;
1349 register int *__ptid __asm__("a4") = parent_tidptr;
1350 register void *__tls __asm__("a5") = newtls;
1351 register int *__ctid __asm__("a6") = child_tidptr;
1352
1353 __asm__ __volatile__(
1354 "mv a0,a2\n" /* flags */
1355 "mv a2,a4\n" /* ptid */
1356 "mv a3,a5\n" /* tls */
1357 "mv a4,a6\n" /* ctid */
1358 "addi a7, zero, %9\n" /* clone */
1359
1360 "ecall\n"
1361
1362 /* if (%r0 != 0)
1363 * return %r0;
1364 */
1365 "bnez a0, 1f\n"
1366
1367 /* In the child, now. Call "fn(arg)". */
1368 "ld a0, 8(sp)\n"
1369 "ld a1, 16(sp)\n"
1370 "jalr a1\n"
1371
1372 /* Call _exit(%r0). */
1373 "addi a7, zero, %10\n"
1374 "ecall\n"
1375 "1:\n"
1376
1377 : "=r"(res)
1378 : "i"(-EINVAL22), "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg),
1379 "r"(__ptid), "r"(__tls), "r"(__ctid), "i"(__NR_clone56), "i"(__NR_exit60)
1380 : "ra", "memory");
1381 return res;
1382}
1383#elif defined(__aarch64__)
1384uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1385 int *parent_tidptr, void *newtls, int *child_tidptr) {
1386 long long res;
1387 if (!fn || !child_stack)
1388 return -EINVAL22;
1389 CHECK_EQ(0, (uptr)child_stack % 16)do { __sanitizer::u64 v1 = (__sanitizer::u64)((0)); __sanitizer
::u64 v2 = (__sanitizer::u64)(((uptr)child_stack % 16)); if (
__builtin_expect(!!(!(v1 == v2)), 0)) __sanitizer::CheckFailed
("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1389, "(" "(0)" ") " "==" " (" "((uptr)child_stack % 16)" ")"
, v1, v2); } while (false);
1390 child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
1391 ((unsigned long long *)child_stack)[0] = (uptr)fn;
1392 ((unsigned long long *)child_stack)[1] = (uptr)arg;
1393
1394 register int (*__fn)(void *) __asm__("x0") = fn;
1395 register void *__stack __asm__("x1") = child_stack;
1396 register int __flags __asm__("x2") = flags;
1397 register void *__arg __asm__("x3") = arg;
1398 register int *__ptid __asm__("x4") = parent_tidptr;
1399 register void *__tls __asm__("x5") = newtls;
1400 register int *__ctid __asm__("x6") = child_tidptr;
1401
1402 __asm__ __volatile__(
1403 "mov x0,x2\n" /* flags */
1404 "mov x2,x4\n" /* ptid */
1405 "mov x3,x5\n" /* tls */
1406 "mov x4,x6\n" /* ctid */
1407 "mov x8,%9\n" /* clone */
1408
1409 "svc 0x0\n"
1410
1411 /* if (%r0 != 0)
1412 * return %r0;
1413 */
1414 "cmp x0, #0\n"
1415 "bne 1f\n"
1416
1417 /* In the child, now. Call "fn(arg)". */
1418 "ldp x1, x0, [sp], #16\n"
1419 "blr x1\n"
1420
1421 /* Call _exit(%r0). */
1422 "mov x8, %10\n"
1423 "svc 0x0\n"
1424 "1:\n"
1425
1426 : "=r" (res)
1427 : "i"(-EINVAL22),
1428 "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg),
1429 "r"(__ptid), "r"(__tls), "r"(__ctid),
1430 "i"(__NR_clone56), "i"(__NR_exit60)
1431 : "x30", "memory");
1432 return res;
1433}
1434#elif defined(__powerpc64__)
1435uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1436 int *parent_tidptr, void *newtls, int *child_tidptr) {
1437 long long res;
1438// Stack frame structure.
1439#if SANITIZER_PPC64V10
1440// Back chain == 0 (SP + 112)
1441// Frame (112 bytes):
1442// Parameter save area (SP + 48), 8 doublewords
1443// TOC save area (SP + 40)
1444// Link editor doubleword (SP + 32)
1445// Compiler doubleword (SP + 24)
1446// LR save area (SP + 16)
1447// CR save area (SP + 8)
1448// Back chain (SP + 0)
1449# define FRAME_SIZE 112
1450# define FRAME_TOC_SAVE_OFFSET 40
1451#elif SANITIZER_PPC64V20
1452// Back chain == 0 (SP + 32)
1453// Frame (32 bytes):
1454// TOC save area (SP + 24)
1455// LR save area (SP + 16)
1456// CR save area (SP + 8)
1457// Back chain (SP + 0)
1458# define FRAME_SIZE 32
1459# define FRAME_TOC_SAVE_OFFSET 24
1460#else
1461# error "Unsupported PPC64 ABI"
1462#endif
1463 if (!fn || !child_stack)
1464 return -EINVAL22;
1465 CHECK_EQ(0, (uptr)child_stack % 16)do { __sanitizer::u64 v1 = (__sanitizer::u64)((0)); __sanitizer
::u64 v2 = (__sanitizer::u64)(((uptr)child_stack % 16)); if (
__builtin_expect(!!(!(v1 == v2)), 0)) __sanitizer::CheckFailed
("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1465, "(" "(0)" ") " "==" " (" "((uptr)child_stack % 16)" ")"
, v1, v2); } while (false);
1466
1467 register int (*__fn)(void *) __asm__("r3") = fn;
1468 register void *__cstack __asm__("r4") = child_stack;
1469 register int __flags __asm__("r5") = flags;
1470 register void *__arg __asm__("r6") = arg;
1471 register int *__ptidptr __asm__("r7") = parent_tidptr;
1472 register void *__newtls __asm__("r8") = newtls;
1473 register int *__ctidptr __asm__("r9") = child_tidptr;
1474
1475 __asm__ __volatile__(
1476 /* fn and arg are saved across the syscall */
1477 "mr 28, %5\n\t"
1478 "mr 27, %8\n\t"
1479
1480 /* syscall
1481 r0 == __NR_clone
1482 r3 == flags
1483 r4 == child_stack
1484 r5 == parent_tidptr
1485 r6 == newtls
1486 r7 == child_tidptr */
1487 "mr 3, %7\n\t"
1488 "mr 5, %9\n\t"
1489 "mr 6, %10\n\t"
1490 "mr 7, %11\n\t"
1491 "li 0, %3\n\t"
1492 "sc\n\t"
1493
1494 /* Test if syscall was successful */
1495 "cmpdi cr1, 3, 0\n\t"
1496 "crandc cr1*4+eq, cr1*4+eq, cr0*4+so\n\t"
1497 "bne- cr1, 1f\n\t"
1498
1499 /* Set up stack frame */
1500 "li 29, 0\n\t"
1501 "stdu 29, -8(1)\n\t"
1502 "stdu 1, -%12(1)\n\t"
1503 /* Do the function call */
1504 "std 2, %13(1)\n\t"
1505#if SANITIZER_PPC64V10
1506 "ld 0, 0(28)\n\t"
1507 "ld 2, 8(28)\n\t"
1508 "mtctr 0\n\t"
1509#elif SANITIZER_PPC64V20
1510 "mr 12, 28\n\t"
1511 "mtctr 12\n\t"
1512#else
1513# error "Unsupported PPC64 ABI"
1514#endif
1515 "mr 3, 27\n\t"
1516 "bctrl\n\t"
1517 "ld 2, %13(1)\n\t"
1518
1519 /* Call _exit(r3) */
1520 "li 0, %4\n\t"
1521 "sc\n\t"
1522
1523 /* Return to parent */
1524 "1:\n\t"
1525 "mr %0, 3\n\t"
1526 : "=r" (res)
1527 : "0" (-1),
1528 "i" (EINVAL22),
1529 "i" (__NR_clone56),
1530 "i" (__NR_exit60),
1531 "r" (__fn),
1532 "r" (__cstack),
1533 "r" (__flags),
1534 "r" (__arg),
1535 "r" (__ptidptr),
1536 "r" (__newtls),
1537 "r" (__ctidptr),
1538 "i" (FRAME_SIZE),
1539 "i" (FRAME_TOC_SAVE_OFFSET)
1540 : "cr0", "cr1", "memory", "ctr", "r0", "r27", "r28", "r29");
1541 return res;
1542}
1543#elif defined(__i386__) && SANITIZER_LINUX1
1544uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1545 int *parent_tidptr, void *newtls, int *child_tidptr) {
1546 int res;
1547 if (!fn || !child_stack)
1548 return -EINVAL22;
1549 CHECK_EQ(0, (uptr)child_stack % 16)do { __sanitizer::u64 v1 = (__sanitizer::u64)((0)); __sanitizer
::u64 v2 = (__sanitizer::u64)(((uptr)child_stack % 16)); if (
__builtin_expect(!!(!(v1 == v2)), 0)) __sanitizer::CheckFailed
("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 1549, "(" "(0)" ") " "==" " (" "((uptr)child_stack % 16)" ")"
, v1, v2); } while (false);
1550 child_stack = (char *)child_stack - 7 * sizeof(unsigned int);
1551 ((unsigned int *)child_stack)[0] = (uptr)flags;
1552 ((unsigned int *)child_stack)[1] = (uptr)0;
1553 ((unsigned int *)child_stack)[2] = (uptr)fn;
1554 ((unsigned int *)child_stack)[3] = (uptr)arg;
1555 __asm__ __volatile__(
1556 /* %eax = syscall(%eax = SYSCALL(clone),
1557 * %ebx = flags,
1558 * %ecx = child_stack,
1559 * %edx = parent_tidptr,
1560 * %esi = new_tls,
1561 * %edi = child_tidptr)
1562 */
1563
1564 /* Obtain flags */
1565 "movl (%%ecx), %%ebx\n"
1566 /* Do the system call */
1567 "pushl %%ebx\n"
1568 "pushl %%esi\n"
1569 "pushl %%edi\n"
1570 /* Remember the flag value. */
1571 "movl %%ebx, (%%ecx)\n"
1572 "int $0x80\n"
1573 "popl %%edi\n"
1574 "popl %%esi\n"
1575 "popl %%ebx\n"
1576
1577 /* if (%eax != 0)
1578 * return;
1579 */
1580
1581 "test %%eax,%%eax\n"
1582 "jnz 1f\n"
1583
1584 /* terminate the stack frame */
1585 "xorl %%ebp,%%ebp\n"
1586 /* Call FN. */
1587 "call *%%ebx\n"
1588#ifdef PIC
1589 "call here\n"
1590 "here:\n"
1591 "popl %%ebx\n"
1592 "addl $_GLOBAL_OFFSET_TABLE_+[.-here], %%ebx\n"
1593#endif
1594 /* Call exit */
1595 "movl %%eax, %%ebx\n"
1596 "movl %2, %%eax\n"
1597 "int $0x80\n"
1598 "1:\n"
1599 : "=a" (res)
1600 : "a"(SYSCALL(clone)56), "i"(SYSCALL(exit)60),
1601 "c"(child_stack),
1602 "d"(parent_tidptr),
1603 "S"(newtls),
1604 "D"(child_tidptr)
1605 : "memory");
1606 return res;
1607}
1608#elif defined(__arm__) && SANITIZER_LINUX1
1609uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
1610 int *parent_tidptr, void *newtls, int *child_tidptr) {
1611 unsigned int res;
1612 if (!fn || !child_stack)
1613 return -EINVAL22;
1614 child_stack = (char *)child_stack - 2 * sizeof(unsigned int);
1615 ((unsigned int *)child_stack)[0] = (uptr)fn;
1616 ((unsigned int *)child_stack)[1] = (uptr)arg;
1617 register int r0 __asm__("r0") = flags;
1618 register void *r1 __asm__("r1") = child_stack;
1619 register int *r2 __asm__("r2") = parent_tidptr;
1620 register void *r3 __asm__("r3") = newtls;
1621 register int *r4 __asm__("r4") = child_tidptr;
1622 register int r7 __asm__("r7") = __NR_clone56;
1623
1624#if __ARM_ARCH > 4 || defined (__ARM_ARCH_4T__)
1625# define ARCH_HAS_BX
1626#endif
1627#if __ARM_ARCH > 4
1628# define ARCH_HAS_BLX
1629#endif
1630
1631#ifdef ARCH_HAS_BX
1632# ifdef ARCH_HAS_BLX
1633# define BLX(R) "blx " #R "\n"
1634# else
1635# define BLX(R) "mov lr, pc; bx " #R "\n"
1636# endif
1637#else
1638# define BLX(R) "mov lr, pc; mov pc," #R "\n"
1639#endif
1640
1641 __asm__ __volatile__(
1642 /* %r0 = syscall(%r7 = SYSCALL(clone),
1643 * %r0 = flags,
1644 * %r1 = child_stack,
1645 * %r2 = parent_tidptr,
1646 * %r3 = new_tls,
1647 * %r4 = child_tidptr)
1648 */
1649
1650 /* Do the system call */
1651 "swi 0x0\n"
1652
1653 /* if (%r0 != 0)
1654 * return %r0;
1655 */
1656 "cmp r0, #0\n"
1657 "bne 1f\n"
1658
1659 /* In the child, now. Call "fn(arg)". */
1660 "ldr r0, [sp, #4]\n"
1661 "ldr ip, [sp], #8\n"
1662 BLX(ip)
1663 /* Call _exit(%r0). */
1664 "mov r7, %7\n"
1665 "swi 0x0\n"
1666 "1:\n"
1667 "mov %0, r0\n"
1668 : "=r"(res)
1669 : "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r7),
1670 "i"(__NR_exit60)
1671 : "memory");
1672 return res;
1673}
1674#endif // defined(__x86_64__) && SANITIZER_LINUX
1675
1676#if SANITIZER_LINUX1
1677int internal_uname(struct utsname *buf) {
1678 return internal_syscall(SYSCALL(uname)63, buf);
1679}
1680#endif
1681
1682#if SANITIZER_ANDROID0
1683#if __ANDROID_API__ < 21
1684extern "C" __attribute__((weak)) int dl_iterate_phdr(
1685 int (*)(struct dl_phdr_info *, size_t, void *), void *);
1686#endif
1687
1688static int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size,
1689 void *data) {
1690 // Any name starting with "lib" indicates a bug in L where library base names
1691 // are returned instead of paths.
1692 if (info->dlpi_name && info->dlpi_name[0] == 'l' &&
1693 info->dlpi_name[1] == 'i' && info->dlpi_name[2] == 'b') {
1694 *(bool *)data = true;
1695 return 1;
1696 }
1697 return 0;
1698}
1699
1700static atomic_uint32_t android_api_level;
1701
1702static AndroidApiLevel AndroidDetectApiLevelStatic() {
1703#if __ANDROID_API__ <= 19
1704 return ANDROID_KITKAT;
1705#elif __ANDROID_API__ <= 22
1706 return ANDROID_LOLLIPOP_MR1;
1707#else
1708 return ANDROID_POST_LOLLIPOP;
1709#endif
1710}
1711
1712static AndroidApiLevel AndroidDetectApiLevel() {
1713 if (!&dl_iterate_phdr)
1714 return ANDROID_KITKAT; // K or lower
1715 bool base_name_seen = false;
1716 dl_iterate_phdr(dl_iterate_phdr_test_cb, &base_name_seen);
1717 if (base_name_seen)
1718 return ANDROID_LOLLIPOP_MR1; // L MR1
1719 return ANDROID_POST_LOLLIPOP; // post-L
1720 // Plain L (API level 21) is completely broken wrt ASan and not very
1721 // interesting to detect.
1722}
1723
1724extern "C" __attribute__((weak)) void* _DYNAMIC;
1725
1726AndroidApiLevel AndroidGetApiLevel() {
1727 AndroidApiLevel level =
1728 (AndroidApiLevel)atomic_load(&android_api_level, memory_order_relaxed);
1729 if (level) return level;
1730 level = &_DYNAMIC == nullptr ? AndroidDetectApiLevelStatic()
1731 : AndroidDetectApiLevel();
1732 atomic_store(&android_api_level, level, memory_order_relaxed);
1733 return level;
1734}
1735
1736#endif
1737
1738static HandleSignalMode GetHandleSignalModeImpl(int signum) {
1739 switch (signum) {
1740 case SIGABRT6:
1741 return common_flags()->handle_abort;
1742 case SIGILL4:
1743 return common_flags()->handle_sigill;
1744 case SIGTRAP5:
1745 return common_flags()->handle_sigtrap;
1746 case SIGFPE8:
1747 return common_flags()->handle_sigfpe;
1748 case SIGSEGV11:
1749 return common_flags()->handle_segv;
1750 case SIGBUS7:
1751 return common_flags()->handle_sigbus;
1752 }
1753 return kHandleSignalNo;
1754}
1755
1756HandleSignalMode GetHandleSignalMode(int signum) {
1757 HandleSignalMode result = GetHandleSignalModeImpl(signum);
1758 if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler)
1759 return kHandleSignalExclusive;
1760 return result;
1761}
1762
1763#if !SANITIZER_GO0
1764void *internal_start_thread(void *(*func)(void *arg), void *arg) {
1765 // Start the thread with signals blocked, otherwise it can steal user signals.
1766 __sanitizer_sigset_t set, old;
1767 internal_sigfillset(&set);
1768#if SANITIZER_LINUX1 && !SANITIZER_ANDROID0
1769 // Glibc uses SIGSETXID signal during setuid call. If this signal is blocked
1770 // on any thread, setuid call hangs (see test/tsan/setuid.c).
1771 internal_sigdelset(&set, 33);
1772#endif
1773 internal_sigprocmask(SIG_SETMASK2, &set, &old);
1774 void *th;
1775 real_pthread_create(&th, nullptr, func, arg);
1776 internal_sigprocmask(SIG_SETMASK2, &old, nullptr);
1777 return th;
1778}
1779
1780void internal_join_thread(void *th) {
1781 real_pthread_join(th, nullptr);
1782}
1783#else
1784void *internal_start_thread(void *(*func)(void *), void *arg) { return 0; }
1785
1786void internal_join_thread(void *th) {}
1787#endif
1788
1789#if defined(__aarch64__)
1790// Android headers in the older NDK releases miss this definition.
1791struct __sanitizer_esr_context {
1792 struct _aarch64_ctx head;
1793 uint64_t esr;
1794};
1795
1796static bool Aarch64GetESR(ucontext_t *ucontext, u64 *esr) {
1797 static const u32 kEsrMagic = 0x45535201;
1798 u8 *aux = ucontext->uc_mcontext.__reserved;
1799 while (true) {
1800 _aarch64_ctx *ctx = (_aarch64_ctx *)aux;
1801 if (ctx->size == 0) break;
1802 if (ctx->magic == kEsrMagic) {
1803 *esr = ((__sanitizer_esr_context *)ctx)->esr;
1804 return true;
1805 }
1806 aux += ctx->size;
1807 }
1808 return false;
1809}
1810#endif
1811
1812using Context = ucontext_t;
1813
1814SignalContext::WriteFlag SignalContext::GetWriteFlag() const {
1815 Context *ucontext = (Context *)context;
1816#if defined(__x86_64__1) || defined(__i386__)
1817 static const uptr PF_WRITE = 1U << 1;
1818#if SANITIZER_FREEBSD0
1819 uptr err = ucontext->uc_mcontext.mc_err;
1820#elif SANITIZER_NETBSD0
1821 uptr err = ucontext->uc_mcontext.__gregs[_REG_ERR];
1822#elif SANITIZER_SOLARIS0 && defined(__i386__)
1823 const int Err = 13;
1824 uptr err = ucontext->uc_mcontext.gregs[Err];
1825#else
1826 uptr err = ucontext->uc_mcontext.gregs[REG_ERRREG_ERR];
1827#endif // SANITIZER_FREEBSD
1828 return err & PF_WRITE ? WRITE : READ;
1829#elif defined(__mips__)
1830 uint32_t *exception_source;
1831 uint32_t faulty_instruction;
1832 uint32_t op_code;
1833
1834 exception_source = (uint32_t *)ucontext->uc_mcontext.pc;
1835 faulty_instruction = (uint32_t)(*exception_source);
1836
1837 op_code = (faulty_instruction >> 26) & 0x3f;
1838
1839 // FIXME: Add support for FPU, microMIPS, DSP, MSA memory instructions.
1840 switch (op_code) {
1841 case 0x28: // sb
1842 case 0x29: // sh
1843 case 0x2b: // sw
1844 case 0x3f: // sd
1845#if __mips_isa_rev < 6
1846 case 0x2c: // sdl
1847 case 0x2d: // sdr
1848 case 0x2a: // swl
1849 case 0x2e: // swr
1850#endif
1851 return SignalContext::WRITE;
1852
1853 case 0x20: // lb
1854 case 0x24: // lbu
1855 case 0x21: // lh
1856 case 0x25: // lhu
1857 case 0x23: // lw
1858 case 0x27: // lwu
1859 case 0x37: // ld
1860#if __mips_isa_rev < 6
1861 case 0x1a: // ldl
1862 case 0x1b: // ldr
1863 case 0x22: // lwl
1864 case 0x26: // lwr
1865#endif
1866 return SignalContext::READ;
1867#if __mips_isa_rev == 6
1868 case 0x3b: // pcrel
1869 op_code = (faulty_instruction >> 19) & 0x3;
1870 switch (op_code) {
1871 case 0x1: // lwpc
1872 case 0x2: // lwupc
1873 return SignalContext::READ;
1874 }
1875#endif
1876 }
1877 return SignalContext::UNKNOWN;
1878#elif defined(__arm__)
1879 static const uptr FSR_WRITE = 1U << 11;
1880 uptr fsr = ucontext->uc_mcontext.error_code;
1881 return fsr & FSR_WRITE ? WRITE : READ;
1882#elif defined(__aarch64__)
1883 static const u64 ESR_ELx_WNR = 1U << 6;
1884 u64 esr;
1885 if (!Aarch64GetESR(ucontext, &esr)) return UNKNOWN;
1886 return esr & ESR_ELx_WNR ? WRITE : READ;
1887#elif defined(__sparc__)
1888 // Decode the instruction to determine the access type.
1889 // From OpenSolaris $SRC/uts/sun4/os/trap.c (get_accesstype).
1890#if SANITIZER_SOLARIS0
1891 uptr pc = ucontext->uc_mcontext.gregs[REG_PC];
1892#else
1893 // Historical BSDism here.
1894 struct sigcontext *scontext = (struct sigcontext *)context;
1895#if defined(__arch64__)
1896 uptr pc = scontext->sigc_regs.tpc;
1897#else
1898 uptr pc = scontext->si_regs.pc;
1899#endif
1900#endif
1901 u32 instr = *(u32 *)pc;
1902 return (instr >> 21) & 1 ? WRITE: READ;
1903#elif defined(__riscv)
1904 unsigned long pc = ucontext->uc_mcontext.__gregs[REG_PC];
1905 unsigned faulty_instruction = *(uint16_t *)pc;
1906
1907#if defined(__riscv_compressed)
1908 if ((faulty_instruction & 0x3) != 0x3) { // it's a compressed instruction
1909 // set op_bits to the instruction bits [1, 0, 15, 14, 13]
1910 unsigned op_bits =
1911 ((faulty_instruction & 0x3) << 3) | (faulty_instruction >> 13);
1912 unsigned rd = faulty_instruction & 0xF80; // bits 7-11, inclusive
1913 switch (op_bits) {
1914 case 0b10'010: // c.lwsp (rd != x0)
1915#if __riscv_xlen == 64
1916 case 0b10'011: // c.ldsp (rd != x0)
1917#endif
1918 return rd ? SignalContext::READ : SignalContext::UNKNOWN;
1919 case 0b00'010: // c.lw
1920#if __riscv_flen >= 32 && __riscv_xlen == 32
1921 case 0b10'011: // c.flwsp
1922#endif
1923#if __riscv_flen >= 32 || __riscv_xlen == 64
1924 case 0b00'011: // c.flw / c.ld
1925#endif
1926#if __riscv_flen == 64
1927 case 0b00'001: // c.fld
1928 case 0b10'001: // c.fldsp
1929#endif
1930 return SignalContext::READ;
1931 case 0b00'110: // c.sw
1932 case 0b10'110: // c.swsp
1933#if __riscv_flen >= 32 || __riscv_xlen == 64
1934 case 0b00'111: // c.fsw / c.sd
1935 case 0b10'111: // c.fswsp / c.sdsp
1936#endif
1937#if __riscv_flen == 64
1938 case 0b00'101: // c.fsd
1939 case 0b10'101: // c.fsdsp
1940#endif
1941 return SignalContext::WRITE;
1942 default:
1943 return SignalContext::UNKNOWN;
1944 }
1945 }
1946#endif
1947
1948 unsigned opcode = faulty_instruction & 0x7f; // lower 7 bits
1949 unsigned funct3 = (faulty_instruction >> 12) & 0x7; // bits 12-14, inclusive
1950 switch (opcode) {
1951 case 0b0000011: // loads
1952 switch (funct3) {
1953 case 0b000: // lb
1954 case 0b001: // lh
1955 case 0b010: // lw
1956#if __riscv_xlen == 64
1957 case 0b011: // ld
1958#endif
1959 case 0b100: // lbu
1960 case 0b101: // lhu
1961 return SignalContext::READ;
1962 default:
1963 return SignalContext::UNKNOWN;
1964 }
1965 case 0b0100011: // stores
1966 switch (funct3) {
1967 case 0b000: // sb
1968 case 0b001: // sh
1969 case 0b010: // sw
1970#if __riscv_xlen == 64
1971 case 0b011: // sd
1972#endif
1973 return SignalContext::WRITE;
1974 default:
1975 return SignalContext::UNKNOWN;
1976 }
1977#if __riscv_flen >= 32
1978 case 0b0000111: // floating-point loads
1979 switch (funct3) {
1980 case 0b010: // flw
1981#if __riscv_flen == 64
1982 case 0b011: // fld
1983#endif
1984 return SignalContext::READ;
1985 default:
1986 return SignalContext::UNKNOWN;
1987 }
1988 case 0b0100111: // floating-point stores
1989 switch (funct3) {
1990 case 0b010: // fsw
1991#if __riscv_flen == 64
1992 case 0b011: // fsd
1993#endif
1994 return SignalContext::WRITE;
1995 default:
1996 return SignalContext::UNKNOWN;
1997 }
1998#endif
1999 default:
2000 return SignalContext::UNKNOWN;
2001 }
2002#else
2003 (void)ucontext;
2004 return UNKNOWN; // FIXME: Implement.
2005#endif
2006}
2007
2008bool SignalContext::IsTrueFaultingAddress() const {
2009 auto si = static_cast<const siginfo_t *>(siginfo);
2010 // SIGSEGV signals without a true fault address have si_code set to 128.
2011 return si->si_signo == SIGSEGV11 && si->si_code != 128;
2012}
2013
2014void SignalContext::DumpAllRegisters(void *context) {
2015 // FIXME: Implement this.
2016}
2017
2018static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) {
2019#if SANITIZER_NETBSD0
2020 // This covers all NetBSD architectures
2021 ucontext_t *ucontext = (ucontext_t *)context;
2022 *pc = _UC_MACHINE_PC(ucontext);
2023 *bp = _UC_MACHINE_FP(ucontext);
2024 *sp = _UC_MACHINE_SP(ucontext);
2025#elif defined(__arm__)
2026 ucontext_t *ucontext = (ucontext_t*)context;
2027 *pc = ucontext->uc_mcontext.arm_pc;
2028 *bp = ucontext->uc_mcontext.arm_fp;
2029 *sp = ucontext->uc_mcontext.arm_sp;
2030#elif defined(__aarch64__)
2031 ucontext_t *ucontext = (ucontext_t*)context;
2032 *pc = ucontext->uc_mcontext.pc;
2033 *bp = ucontext->uc_mcontext.regs[29];
2034 *sp = ucontext->uc_mcontext.sp;
2035#elif defined(__hppa__)
2036 ucontext_t *ucontext = (ucontext_t*)context;
2037 *pc = ucontext->uc_mcontext.sc_iaoq[0];
2038 /* GCC uses %r3 whenever a frame pointer is needed. */
2039 *bp = ucontext->uc_mcontext.sc_gr[3];
2040 *sp = ucontext->uc_mcontext.sc_gr[30];
2041#elif defined(__x86_64__1)
2042# if SANITIZER_FREEBSD0
2043 ucontext_t *ucontext = (ucontext_t*)context;
2044 *pc = ucontext->uc_mcontext.mc_rip;
2045 *bp = ucontext->uc_mcontext.mc_rbp;
2046 *sp = ucontext->uc_mcontext.mc_rsp;
2047# else
2048 ucontext_t *ucontext = (ucontext_t*)context;
2049 *pc = ucontext->uc_mcontext.gregs[REG_RIPREG_RIP];
2050 *bp = ucontext->uc_mcontext.gregs[REG_RBPREG_RBP];
2051 *sp = ucontext->uc_mcontext.gregs[REG_RSPREG_RSP];
2052# endif
2053#elif defined(__i386__)
2054# if SANITIZER_FREEBSD0
2055 ucontext_t *ucontext = (ucontext_t*)context;
2056 *pc = ucontext->uc_mcontext.mc_eip;
2057 *bp = ucontext->uc_mcontext.mc_ebp;
2058 *sp = ucontext->uc_mcontext.mc_esp;
2059# else
2060 ucontext_t *ucontext = (ucontext_t*)context;
2061# if SANITIZER_SOLARIS0
2062 /* Use the numeric values: the symbolic ones are undefined by llvm
2063 include/llvm/Support/Solaris.h. */
2064# ifndef REG_EIP
2065# define REG_EIP 14 // REG_PC
2066# endif
2067# ifndef REG_EBP
2068# define REG_EBP 6 // REG_FP
2069# endif
2070# ifndef REG_UESP
2071# define REG_UESP 17 // REG_SP
2072# endif
2073# endif
2074 *pc = ucontext->uc_mcontext.gregs[REG_EIP];
2075 *bp = ucontext->uc_mcontext.gregs[REG_EBP];
2076 *sp = ucontext->uc_mcontext.gregs[REG_UESP];
2077# endif
2078#elif defined(__powerpc__) || defined(__powerpc64__)
2079 ucontext_t *ucontext = (ucontext_t*)context;
2080 *pc = ucontext->uc_mcontext.regs->nip;
2081 *sp = ucontext->uc_mcontext.regs->gpr[PT_R1];
2082 // The powerpc{,64}-linux ABIs do not specify r31 as the frame
2083 // pointer, but GCC always uses r31 when we need a frame pointer.
2084 *bp = ucontext->uc_mcontext.regs->gpr[PT_R31];
2085#elif defined(__sparc__)
2086#if defined(__arch64__) || defined(__sparcv9)
2087#define STACK_BIAS 2047
2088#else
2089#define STACK_BIAS 0
2090# endif
2091# if SANITIZER_SOLARIS0
2092 ucontext_t *ucontext = (ucontext_t *)context;
2093 *pc = ucontext->uc_mcontext.gregs[REG_PC];
2094 *sp = ucontext->uc_mcontext.gregs[REG_O6] + STACK_BIAS;
2095#else
2096 // Historical BSDism here.
2097 struct sigcontext *scontext = (struct sigcontext *)context;
2098#if defined(__arch64__)
2099 *pc = scontext->sigc_regs.tpc;
2100 *sp = scontext->sigc_regs.u_regs[14] + STACK_BIAS;
2101#else
2102 *pc = scontext->si_regs.pc;
2103 *sp = scontext->si_regs.u_regs[14];
2104#endif
2105# endif
2106 *bp = (uptr)((uhwptr *)*sp)[14] + STACK_BIAS;
2107#elif defined(__mips__)
2108 ucontext_t *ucontext = (ucontext_t*)context;
2109 *pc = ucontext->uc_mcontext.pc;
2110 *bp = ucontext->uc_mcontext.gregs[30];
2111 *sp = ucontext->uc_mcontext.gregs[29];
2112#elif defined(__s390__)
2113 ucontext_t *ucontext = (ucontext_t*)context;
2114# if defined(__s390x__)
2115 *pc = ucontext->uc_mcontext.psw.addr;
2116# else
2117 *pc = ucontext->uc_mcontext.psw.addr & 0x7fffffff;
2118# endif
2119 *bp = ucontext->uc_mcontext.gregs[11];
2120 *sp = ucontext->uc_mcontext.gregs[15];
2121#elif defined(__riscv)
2122 ucontext_t *ucontext = (ucontext_t*)context;
2123 *pc = ucontext->uc_mcontext.__gregs[REG_PC];
2124 *bp = ucontext->uc_mcontext.__gregs[REG_S0];
2125 *sp = ucontext->uc_mcontext.__gregs[REG_SP];
2126#else
2127# error "Unsupported arch"
2128#endif
2129}
2130
2131void SignalContext::InitPcSpBp() { GetPcSpBp(context, &pc, &sp, &bp); }
2132
2133void InitializePlatformEarly() {
2134 // Do nothing.
2135}
2136
2137void MaybeReexec() {
2138 // No need to re-exec on Linux.
2139}
2140
2141void CheckASLR() {
2142#if SANITIZER_NETBSD0
2143 int mib[3];
2144 int paxflags;
2145 uptr len = sizeof(paxflags);
2146
2147 mib[0] = CTL_PROC;
2148 mib[1] = internal_getpid();
2149 mib[2] = PROC_PID_PAXFLAGS;
2150
2151 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)__builtin_expect(!!(internal_sysctl(mib, 3, &paxflags, &
len, __null, 0) == -1), 0)) {
2152 Printf("sysctl failed\n");
2153 Die();
2154 }
2155
2156 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_ASLR)__builtin_expect(!!(paxflags & CTL_PROC_PAXFLAGS_ASLR), 0
)) {
2157 Printf("This sanitizer is not compatible with enabled ASLR.\n"
2158 "To disable ASLR, please run \"paxctl +a %s\" and try again.\n",
2159 GetArgv()[0]);
2160 Die();
2161 }
2162#elif SANITIZER_PPC64V20
2163 // Disable ASLR for Linux PPC64LE.
2164 int old_personality = personality(0xffffffff);
2165 if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) {
2166 VReport(1, "WARNING: Program is being run with address space layout "do { if ((uptr)Verbosity() >= (1)) Report("WARNING: Program is being run with address space layout "
"randomization (ASLR) enabled which prevents the thread and "
"memory sanitizers from working on powerpc64le.\n" "ASLR will be disabled and the program re-executed.\n"
); } while (0)
2167 "randomization (ASLR) enabled which prevents the thread and "do { if ((uptr)Verbosity() >= (1)) Report("WARNING: Program is being run with address space layout "
"randomization (ASLR) enabled which prevents the thread and "
"memory sanitizers from working on powerpc64le.\n" "ASLR will be disabled and the program re-executed.\n"
); } while (0)
2168 "memory sanitizers from working on powerpc64le.\n"do { if ((uptr)Verbosity() >= (1)) Report("WARNING: Program is being run with address space layout "
"randomization (ASLR) enabled which prevents the thread and "
"memory sanitizers from working on powerpc64le.\n" "ASLR will be disabled and the program re-executed.\n"
); } while (0)
2169 "ASLR will be disabled and the program re-executed.\n")do { if ((uptr)Verbosity() >= (1)) Report("WARNING: Program is being run with address space layout "
"randomization (ASLR) enabled which prevents the thread and "
"memory sanitizers from working on powerpc64le.\n" "ASLR will be disabled and the program re-executed.\n"
); } while (0);
2170 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1)do { __sanitizer::u64 v1 = (__sanitizer::u64)((personality(old_personality
| ADDR_NO_RANDOMIZE))); __sanitizer::u64 v2 = (__sanitizer::
u64)((-1)); if (__builtin_expect(!!(!(v1 != v2)), 0)) __sanitizer
::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 2170, "(" "(personality(old_personality | ADDR_NO_RANDOMIZE))"
") " "!=" " (" "(-1)" ")", v1, v2); } while (false);
2171 ReExec();
2172 }
2173#elif SANITIZER_FREEBSD0
2174 int aslr_pie;
2175 uptr len = sizeof(aslr_pie);
2176#if SANITIZER_WORDSIZE64 == 64
2177 if (UNLIKELY(internal_sysctlbyname("kern.elf64.aslr.pie_enable",__builtin_expect(!!(internal_sysctlbyname("kern.elf64.aslr.pie_enable"
, &aslr_pie, &len, __null, 0) == -1), 0)
2178 &aslr_pie, &len, NULL, 0) == -1)__builtin_expect(!!(internal_sysctlbyname("kern.elf64.aslr.pie_enable"
, &aslr_pie, &len, __null, 0) == -1), 0)) {
2179 // We're making things less 'dramatic' here since
2180 // the OID is not necessarily guaranteed to be here
2181 // just yet regarding FreeBSD release
2182 return;
2183 }
2184
2185 if (aslr_pie > 0) {
2186 Printf("This sanitizer is not compatible with enabled ASLR "
2187 "and binaries compiled with PIE\n");
2188 Die();
2189 }
2190#endif
2191 // there might be 32 bits compat for 64 bits
2192 if (UNLIKELY(internal_sysctlbyname("kern.elf32.aslr.pie_enable",__builtin_expect(!!(internal_sysctlbyname("kern.elf32.aslr.pie_enable"
, &aslr_pie, &len, __null, 0) == -1), 0)
2193 &aslr_pie, &len, NULL, 0) == -1)__builtin_expect(!!(internal_sysctlbyname("kern.elf32.aslr.pie_enable"
, &aslr_pie, &len, __null, 0) == -1), 0)) {
2194 return;
2195 }
2196
2197 if (aslr_pie > 0) {
2198 Printf("This sanitizer is not compatible with enabled ASLR "
2199 "and binaries compiled with PIE\n");
2200 Die();
2201 }
2202#else
2203 // Do nothing
2204#endif
2205}
2206
2207void CheckMPROTECT() {
2208#if SANITIZER_NETBSD0
2209 int mib[3];
2210 int paxflags;
2211 uptr len = sizeof(paxflags);
2212
2213 mib[0] = CTL_PROC;
2214 mib[1] = internal_getpid();
2215 mib[2] = PROC_PID_PAXFLAGS;
2216
2217 if (UNLIKELY(internal_sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)__builtin_expect(!!(internal_sysctl(mib, 3, &paxflags, &
len, __null, 0) == -1), 0)) {
2218 Printf("sysctl failed\n");
2219 Die();
2220 }
2221
2222 if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_MPROTECT)__builtin_expect(!!(paxflags & CTL_PROC_PAXFLAGS_MPROTECT
), 0)) {
2223 Printf("This sanitizer is not compatible with enabled MPROTECT\n");
2224 Die();
2225 }
2226#else
2227 // Do nothing
2228#endif
2229}
2230
2231void CheckNoDeepBind(const char *filename, int flag) {
2232#ifdef RTLD_DEEPBIND0x00008
2233 if (flag & RTLD_DEEPBIND0x00008) {
2234 Report(
2235 "You are trying to dlopen a %s shared library with RTLD_DEEPBIND flag"
2236 " which is incompatible with sanitizer runtime "
2237 "(see https://github.com/google/sanitizers/issues/611 for details"
2238 "). If you want to run %s library under sanitizers please remove "
2239 "RTLD_DEEPBIND from dlopen flags.\n",
2240 filename, filename);
2241 Die();
2242 }
2243#endif
2244}
2245
2246uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding,
2247 uptr *largest_gap_found,
2248 uptr *max_occupied_addr) {
2249 UNREACHABLE("FindAvailableMemoryRange is not available")do { do { __sanitizer::u64 v1 = (__sanitizer::u64)((0 &&
"FindAvailableMemoryRange is not available")); __sanitizer::
u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect(!!(!(v1 !=
v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp"
, 2249, "(" "(0 && \"FindAvailableMemoryRange is not available\")"
") " "!=" " (" "0" ")", v1, v2); } while (false); Die(); } while
(0);
2250 return 0;
2251}
2252
2253bool GetRandom(void *buffer, uptr length, bool blocking) {
2254 if (!buffer || !length || length > 256)
2255 return false;
2256#if SANITIZER_USE_GETENTROPY0
2257 uptr rnd = getentropy(buffer, length);
2258 int rverrno = 0;
2259 if (internal_iserror(rnd, &rverrno) && rverrno == EFAULT14)
2260 return false;
2261 else if (rnd == 0)
2262 return true;
2263#endif // SANITIZER_USE_GETENTROPY
2264
2265#if SANITIZER_USE_GETRANDOM1
2266 static atomic_uint8_t skip_getrandom_syscall;
2267 if (!atomic_load_relaxed(&skip_getrandom_syscall)) {
2268 // Up to 256 bytes, getrandom will not be interrupted.
2269 uptr res = internal_syscall(SYSCALL(getrandom)318, buffer, length,
2270 blocking ? 0 : GRND_NONBLOCK1);
2271 int rverrno = 0;
2272 if (internal_iserror(res, &rverrno) && rverrno == ENOSYS38)
2273 atomic_store_relaxed(&skip_getrandom_syscall, 1);
2274 else if (res == length)
2275 return true;
2276 }
2277#endif // SANITIZER_USE_GETRANDOM
2278 // Up to 256 bytes, a read off /dev/urandom will not be interrupted.
2279 // blocking is moot here, O_NONBLOCK has no effect when opening /dev/urandom.
2280 uptr fd = internal_open("/dev/urandom", O_RDONLY00);
2281 if (internal_iserror(fd))
2282 return false;
2283 uptr res = internal_read(fd, buffer, length);
2284 if (internal_iserror(res))
2285 return false;
2286 internal_close(fd);
2287 return true;
2288}
2289
2290} // namespace __sanitizer
2291
2292#endif
←

/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/compiler-rt/lib/sanitizer_common/sanitizer_syscall_linux_x86_64.inc

1//===-- sanitizer_syscall_linux_x86_64.inc ----------------------*- C++ -*-===//
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// Implementations of internal_syscall and internal_iserror for Linux/x86_64.
10//
11//===----------------------------------------------------------------------===//
12
13#define SYSCALL(name)__NR_name __NR_ ## name
14
15static uptr internal_syscall(u64 nr) {
16 u64 retval;
17 asm volatile("syscall" : "=a"(retval) : "a"(nr) : "rcx", "r11",
18 "memory", "cc");
19 return retval;
20}
21
22template <typename T1>
23static uptr internal_syscall(u64 nr, T1 arg1) {
24 u64 retval;
25 asm volatile("syscall" : "=a"(retval) : "a"(nr), "D"((u64)arg1) :
26 "rcx", "r11", "memory", "cc");
27 return retval;
28}
29
30template <typename T1, typename T2>
31static uptr internal_syscall(u64 nr, T1 arg1, T2 arg2) {
32 u64 retval;
33 asm volatile("syscall" : "=a"(retval) : "a"(nr), "D"((u64)arg1),
34 "S"((u64)arg2) : "rcx", "r11", "memory", "cc");
35 return retval;
3
←
Returning without writing to 'arg2->st_size'
→
36}
37
38template <typename T1, typename T2, typename T3>
39static uptr internal_syscall(u64 nr, T1 arg1, T2 arg2, T3 arg3) {
40 u64 retval;
41 asm volatile("syscall" : "=a"(retval) : "a"(nr), "D"((u64)arg1),
42 "S"((u64)arg2), "d"((u64)arg3) : "rcx", "r11", "memory", "cc");
43 return retval;
44}
45
46template <typename T1, typename T2, typename T3, typename T4>
47static uptr internal_syscall(u64 nr, T1 arg1, T2 arg2, T3 arg3, T4 arg4) {
48 u64 retval;
49 asm volatile("mov %5, %%r10;"
50 "syscall" : "=a"(retval) : "a"(nr), "D"((u64)arg1),
51 "S"((u64)arg2), "d"((u64)arg3), "r"((u64)arg4) :
52 "rcx", "r11", "r10", "memory", "cc");
53 return retval;
54}
55
56template <typename T1, typename T2, typename T3, typename T4, typename T5>
57static uptr internal_syscall(u64 nr, T1 arg1, T2 arg2, T3 arg3, T4 arg4,
58 T5 arg5) {
59 u64 retval;
60 asm volatile("mov %5, %%r10;"
61 "mov %6, %%r8;"
62 "syscall" : "=a"(retval) : "a"(nr), "D"((u64)arg1),
63 "S"((u64)arg2), "d"((u64)arg3), "r"((u64)arg4), "r"((u64)arg5) :
64 "rcx", "r11", "r10", "r8", "memory", "cc");
65 return retval;
66}
67
68template <typename T1, typename T2, typename T3, typename T4, typename T5,
69 typename T6>
70static uptr internal_syscall(u64 nr, T1 arg1, T2 arg2, T3 arg3, T4 arg4,
71 T5 arg5, T6 arg6) {
72 u64 retval;
73 asm volatile("mov %5, %%r10;"
74 "mov %6, %%r8;"
75 "mov %7, %%r9;"
76 "syscall" : "=a"(retval) : "a"(nr), "D"((u64)arg1),
77 "S"((u64)arg2), "d"((u64)arg3), "r"((u64)arg4), "r"((u64)arg5),
78 "r"((u64)arg6) : "rcx", "r11", "r10", "r8", "r9",
79 "memory", "cc");
80 return retval;
81}
82
83bool internal_iserror(uptr retval, int *rverrno) {
84 if (retval >= (uptr)-4095) {
85 if (rverrno)
86 *rverrno = -retval;
87 return true;
88 }
89 return false;
90}