1 //===-- sanitizer_linux_libcdep.cpp ---------------------------------------===//
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
7 //===----------------------------------------------------------------------===//
9 // This file is shared between AddressSanitizer and ThreadSanitizer
10 // run-time libraries and implements linux-specific functions from
12 //===----------------------------------------------------------------------===//
14 #include "sanitizer_platform.h"
16 #if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \
17 SANITIZER_OPENBSD || SANITIZER_SOLARIS
19 #include "sanitizer_allocator_internal.h"
20 #include "sanitizer_atomic.h"
21 #include "sanitizer_common.h"
22 #include "sanitizer_file.h"
23 #include "sanitizer_flags.h"
24 #include "sanitizer_freebsd.h"
25 #include "sanitizer_getauxval.h"
26 #include "sanitizer_glibc_version.h"
27 #include "sanitizer_linux.h"
28 #include "sanitizer_placement_new.h"
29 #include "sanitizer_procmaps.h"
31 #include <dlfcn.h> // for dlsym()
35 #include <sys/resource.h>
39 #include <pthread_np.h>
40 #include <osreldate.h>
41 #include <sys/sysctl.h>
42 #define pthread_getattr_np pthread_attr_get_np
46 #include <pthread_np.h>
47 #include <sys/sysctl.h>
51 #include <sys/sysctl.h>
62 #include <android/api-level.h>
63 #if !defined(CPU_COUNT) && !defined(__aarch64__)
66 struct __sanitizer::linux_dirent {
69 unsigned short d_reclen;
75 #if !SANITIZER_ANDROID
80 namespace __sanitizer {
82 SANITIZER_WEAK_ATTRIBUTE int
83 real_sigaction(int signum, const void *act, void *oldact);
85 int internal_sigaction(int signum, const void *act, void *oldact) {
88 return real_sigaction(signum, act, oldact);
90 return sigaction(signum, (const struct sigaction *)act,
91 (struct sigaction *)oldact);
94 void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
98 if (at_initialization) {
99 // This is the main thread. Libpthread may not be initialized yet.
101 CHECK_EQ(getrlimit(RLIMIT_STACK, &rl), 0);
103 // Find the mapping that contains a stack variable.
104 MemoryMappingLayout proc_maps(/*cache_enabled*/true);
105 if (proc_maps.Error()) {
106 *stack_top = *stack_bottom = 0;
109 MemoryMappedSegment segment;
111 while (proc_maps.Next(&segment)) {
112 if ((uptr)&rl < segment.end) break;
113 prev_end = segment.end;
115 CHECK((uptr)&rl >= segment.start && (uptr)&rl < segment.end);
117 // Get stacksize from rlimit, but clip it so that it does not overlap
118 // with other mappings.
119 uptr stacksize = rl.rlim_cur;
120 if (stacksize > segment.end - prev_end) stacksize = segment.end - prev_end;
121 // When running with unlimited stack size, we still want to set some limit.
122 // The unlimited stack size is caused by 'ulimit -s unlimited'.
123 // Also, for some reason, GNU make spawns subprocesses with unlimited stack.
124 if (stacksize > kMaxThreadStackSize)
125 stacksize = kMaxThreadStackSize;
126 *stack_top = segment.end;
127 *stack_bottom = segment.end - stacksize;
131 void *stackaddr = nullptr;
132 #if SANITIZER_SOLARIS
134 CHECK_EQ(thr_stksegment(&ss), 0);
135 stacksize = ss.ss_size;
136 stackaddr = (char *)ss.ss_sp - stacksize;
137 #elif SANITIZER_OPENBSD
139 CHECK_EQ(pthread_stackseg_np(pthread_self(), &sattr), 0);
140 stackaddr = sattr.ss_sp;
141 stacksize = sattr.ss_size;
142 #else // !SANITIZER_SOLARIS
144 pthread_attr_init(&attr);
145 CHECK_EQ(pthread_getattr_np(pthread_self(), &attr), 0);
146 my_pthread_attr_getstack(&attr, &stackaddr, &stacksize);
147 pthread_attr_destroy(&attr);
148 #endif // SANITIZER_SOLARIS
150 *stack_top = (uptr)stackaddr + stacksize;
151 *stack_bottom = (uptr)stackaddr;
155 bool SetEnv(const char *name, const char *value) {
156 void *f = dlsym(RTLD_NEXT, "setenv");
159 typedef int(*setenv_ft)(const char *name, const char *value, int overwrite);
161 CHECK_EQ(sizeof(setenv_f), sizeof(f));
162 internal_memcpy(&setenv_f, &f, sizeof(f));
163 return setenv_f(name, value, 1) == 0;
167 __attribute__((unused)) static bool GetLibcVersion(int *major, int *minor,
169 #ifdef _CS_GNU_LIBC_VERSION
171 uptr len = confstr(_CS_GNU_LIBC_VERSION, buf, sizeof(buf));
172 if (len >= sizeof(buf))
175 static const char kGLibC[] = "glibc ";
176 if (internal_strncmp(buf, kGLibC, sizeof(kGLibC) - 1) != 0)
178 const char *p = buf + sizeof(kGLibC) - 1;
179 *major = internal_simple_strtoll(p, &p, 10);
180 *minor = (*p == '.') ? internal_simple_strtoll(p + 1, &p, 10) : 0;
181 *patch = (*p == '.') ? internal_simple_strtoll(p + 1, &p, 10) : 0;
188 #if !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_GO && \
189 !SANITIZER_NETBSD && !SANITIZER_OPENBSD && !SANITIZER_SOLARIS
190 static uptr g_tls_size;
193 # define CHECK_GET_TLS_STATIC_INFO_VERSION (!__GLIBC_PREREQ(2, 27))
195 # define CHECK_GET_TLS_STATIC_INFO_VERSION 0
198 #if CHECK_GET_TLS_STATIC_INFO_VERSION
199 # define DL_INTERNAL_FUNCTION __attribute__((regparm(3), stdcall))
201 # define DL_INTERNAL_FUNCTION
205 struct GetTlsStaticInfoCall {
206 typedef void (*get_tls_func)(size_t*, size_t*);
208 struct GetTlsStaticInfoRegparmCall {
209 typedef void (*get_tls_func)(size_t*, size_t*) DL_INTERNAL_FUNCTION;
212 template <typename T>
213 void CallGetTls(void* ptr, size_t* size, size_t* align) {
214 typename T::get_tls_func get_tls;
215 CHECK_EQ(sizeof(get_tls), sizeof(ptr));
216 internal_memcpy(&get_tls, &ptr, sizeof(ptr));
217 CHECK_NE(get_tls, 0);
218 get_tls(size, align);
221 bool CmpLibcVersion(int major, int minor, int patch) {
225 if (!GetLibcVersion(&ma, &mi, &pa))
241 // all current supported platforms have 16 bytes stack alignment
242 const size_t kStackAlign = 16;
243 void *get_tls_static_info_ptr = dlsym(RTLD_NEXT, "_dl_get_tls_static_info");
245 size_t tls_align = 0;
246 // On i?86, _dl_get_tls_static_info used to be internal_function, i.e.
247 // __attribute__((regparm(3), stdcall)) before glibc 2.27 and is normal
248 // function in 2.27 and later.
249 if (CHECK_GET_TLS_STATIC_INFO_VERSION && !CmpLibcVersion(2, 27, 0))
250 CallGetTls<GetTlsStaticInfoRegparmCall>(get_tls_static_info_ptr,
251 &tls_size, &tls_align);
253 CallGetTls<GetTlsStaticInfoCall>(get_tls_static_info_ptr,
254 &tls_size, &tls_align);
255 if (tls_align < kStackAlign)
256 tls_align = kStackAlign;
257 g_tls_size = RoundUpTo(tls_size, tls_align);
260 void InitTlsSize() { }
261 #endif // !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_GO &&
262 // !SANITIZER_NETBSD && !SANITIZER_SOLARIS
264 #if (defined(__x86_64__) || defined(__i386__) || defined(__mips__) || \
265 defined(__aarch64__) || defined(__powerpc64__) || defined(__s390__) || \
266 defined(__arm__)) && \
267 SANITIZER_LINUX && !SANITIZER_ANDROID
268 // sizeof(struct pthread) from glibc.
269 static atomic_uintptr_t thread_descriptor_size;
271 uptr ThreadDescriptorSize() {
272 uptr val = atomic_load_relaxed(&thread_descriptor_size);
275 #if defined(__x86_64__) || defined(__i386__) || defined(__arm__)
279 if (GetLibcVersion(&major, &minor, &patch) && major == 2) {
280 /* sizeof(struct pthread) values from various glibc versions. */
282 val = 1728; // Assume only one particular version for x32.
283 // For ARM sizeof(struct pthread) changed in Glibc 2.23.
284 else if (SANITIZER_ARM)
285 val = minor <= 22 ? 1120 : 1216;
287 val = FIRST_32_SECOND_64(1104, 1696);
289 val = FIRST_32_SECOND_64(1120, 1728);
291 val = FIRST_32_SECOND_64(1136, 1728);
293 val = FIRST_32_SECOND_64(1136, 1712);
294 else if (minor == 10)
295 val = FIRST_32_SECOND_64(1168, 1776);
296 else if (minor == 11 || (minor == 12 && patch == 1))
297 val = FIRST_32_SECOND_64(1168, 2288);
298 else if (minor <= 14)
299 val = FIRST_32_SECOND_64(1168, 2304);
301 val = FIRST_32_SECOND_64(1216, 2304);
303 #elif defined(__mips__)
304 // TODO(sagarthakur): add more values as per different glibc versions.
305 val = FIRST_32_SECOND_64(1152, 1776);
306 #elif defined(__aarch64__)
307 // The sizeof (struct pthread) is the same from GLIBC 2.17 to 2.22.
309 #elif defined(__powerpc64__)
310 val = 1776; // from glibc.ppc64le 2.20-8.fc21
311 #elif defined(__s390__)
312 val = FIRST_32_SECOND_64(1152, 1776); // valid for glibc 2.22
315 atomic_store_relaxed(&thread_descriptor_size, val);
319 // The offset at which pointer to self is located in the thread descriptor.
320 const uptr kThreadSelfOffset = FIRST_32_SECOND_64(8, 16);
322 uptr ThreadSelfOffset() {
323 return kThreadSelfOffset;
326 #if defined(__mips__) || defined(__powerpc64__)
327 // TlsPreTcbSize includes size of struct pthread_descr and size of tcb
328 // head structure. It lies before the static tls blocks.
329 static uptr TlsPreTcbSize() {
330 # if defined(__mips__)
331 const uptr kTcbHead = 16; // sizeof (tcbhead_t)
332 # elif defined(__powerpc64__)
333 const uptr kTcbHead = 88; // sizeof (tcbhead_t)
335 const uptr kTlsAlign = 16;
336 const uptr kTlsPreTcbSize =
337 RoundUpTo(ThreadDescriptorSize() + kTcbHead, kTlsAlign);
338 return kTlsPreTcbSize;
344 # if defined(__i386__)
345 asm("mov %%gs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset));
346 # elif defined(__x86_64__)
347 asm("mov %%fs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset));
348 # elif defined(__mips__)
349 // MIPS uses TLS variant I. The thread pointer (in hardware register $29)
350 // points to the end of the TCB + 0x7000. The pthread_descr structure is
351 // immediately in front of the TCB. TlsPreTcbSize() includes the size of the
352 // TCB and the size of pthread_descr.
353 const uptr kTlsTcbOffset = 0x7000;
355 asm volatile(".set push;\
358 .set pop" : "=r" (thread_pointer));
359 descr_addr = thread_pointer - kTlsTcbOffset - TlsPreTcbSize();
360 # elif defined(__aarch64__) || defined(__arm__)
361 descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer()) -
362 ThreadDescriptorSize();
363 # elif defined(__s390__)
364 descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer());
365 # elif defined(__powerpc64__)
366 // PPC64LE uses TLS variant I. The thread pointer (in GPR 13)
367 // points to the end of the TCB + 0x7000. The pthread_descr structure is
368 // immediately in front of the TCB. TlsPreTcbSize() includes the size of the
369 // TCB and the size of pthread_descr.
370 const uptr kTlsTcbOffset = 0x7000;
372 asm("addi %0,13,%1" : "=r"(thread_pointer) : "I"(-kTlsTcbOffset));
373 descr_addr = thread_pointer - TlsPreTcbSize();
375 # error "unsupported CPU arch"
379 #endif // (x86_64 || i386 || MIPS) && SANITIZER_LINUX
381 #if SANITIZER_FREEBSD
382 static void **ThreadSelfSegbase() {
384 # if defined(__i386__)
385 // sysarch(I386_GET_GSBASE, segbase);
386 __asm __volatile("mov %%gs:0, %0" : "=r" (segbase));
387 # elif defined(__x86_64__)
388 // sysarch(AMD64_GET_FSBASE, segbase);
389 __asm __volatile("movq %%fs:0, %0" : "=r" (segbase));
391 # error "unsupported CPU arch"
397 return (uptr)ThreadSelfSegbase()[2];
399 #endif // SANITIZER_FREEBSD
402 static struct tls_tcb * ThreadSelfTlsTcb() {
403 return (struct tls_tcb *)_lwp_getprivate();
407 return (uptr)ThreadSelfTlsTcb()->tcb_pthread;
410 int GetSizeFromHdr(struct dl_phdr_info *info, size_t size, void *data) {
411 const Elf_Phdr *hdr = info->dlpi_phdr;
412 const Elf_Phdr *last_hdr = hdr + info->dlpi_phnum;
414 for (; hdr != last_hdr; ++hdr) {
415 if (hdr->p_type == PT_TLS && info->dlpi_tls_modid == 1) {
416 *(uptr*)data = hdr->p_memsz;
422 #endif // SANITIZER_NETBSD
425 static void GetTls(uptr *addr, uptr *size) {
426 #if SANITIZER_LINUX && !SANITIZER_ANDROID
427 # if defined(__x86_64__) || defined(__i386__) || defined(__s390__)
428 *addr = ThreadSelf();
429 *size = GetTlsSize();
431 *addr += ThreadDescriptorSize();
432 # elif defined(__mips__) || defined(__aarch64__) || defined(__powerpc64__) \
434 *addr = ThreadSelf();
435 *size = GetTlsSize();
440 #elif SANITIZER_FREEBSD
441 void** segbase = ThreadSelfSegbase();
446 // tls_size = round(tls_static_space, tcbalign);
448 // dtv[2] = segbase - tls_static_space;
449 void **dtv = (void**) segbase[1];
450 *addr = (uptr) dtv[2];
451 *size = (*addr == 0) ? 0 : ((uptr) segbase[0] - (uptr) dtv[2]);
453 #elif SANITIZER_NETBSD
454 struct tls_tcb * const tcb = ThreadSelfTlsTcb();
458 // Find size (p_memsz) of dlpi_tls_modid 1 (TLS block of the main program).
459 // ld.elf_so hardcodes the index 1.
460 dl_iterate_phdr(GetSizeFromHdr, size);
463 // The block has been found and tcb_dtv[1] contains the base address
464 *addr = (uptr)tcb->tcb_dtv[1];
467 #elif SANITIZER_OPENBSD
470 #elif SANITIZER_ANDROID
473 #elif SANITIZER_SOLARIS
485 #if SANITIZER_FREEBSD || SANITIZER_ANDROID || SANITIZER_NETBSD || \
486 SANITIZER_OPENBSD || SANITIZER_SOLARIS
488 GetTls(&addr, &size);
490 #elif defined(__mips__) || defined(__powerpc64__)
491 return RoundUpTo(g_tls_size + TlsPreTcbSize(), 16);
498 void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
499 uptr *tls_addr, uptr *tls_size) {
501 // Stub implementation for Go.
502 *stk_addr = *stk_size = *tls_addr = *tls_size = 0;
504 GetTls(tls_addr, tls_size);
506 uptr stack_top, stack_bottom;
507 GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom);
508 *stk_addr = stack_bottom;
509 *stk_size = stack_top - stack_bottom;
512 // If stack and tls intersect, make them non-intersecting.
513 if (*tls_addr > *stk_addr && *tls_addr < *stk_addr + *stk_size) {
514 CHECK_GT(*tls_addr + *tls_size, *stk_addr);
515 CHECK_LE(*tls_addr + *tls_size, *stk_addr + *stk_size);
516 *stk_size -= *tls_size;
517 *tls_addr = *stk_addr + *stk_size;
523 #if !SANITIZER_FREEBSD && !SANITIZER_OPENBSD
524 typedef ElfW(Phdr) Elf_Phdr;
525 #elif SANITIZER_WORDSIZE == 32 && __FreeBSD_version <= 902001 // v9.2
526 #define Elf_Phdr XElf32_Phdr
527 #define dl_phdr_info xdl_phdr_info
528 #define dl_iterate_phdr(c, b) xdl_iterate_phdr((c), (b))
529 #endif // !SANITIZER_FREEBSD && !SANITIZER_OPENBSD
531 struct DlIteratePhdrData {
532 InternalMmapVectorNoCtor<LoadedModule> *modules;
536 static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) {
537 DlIteratePhdrData *data = (DlIteratePhdrData*)arg;
538 InternalScopedString module_name(kMaxPathLength);
541 // First module is the binary itself.
542 ReadBinaryNameCached(module_name.data(), module_name.size());
543 } else if (info->dlpi_name) {
544 module_name.append("%s", info->dlpi_name);
546 if (module_name[0] == '\0')
548 LoadedModule cur_module;
549 cur_module.set(module_name.data(), info->dlpi_addr);
550 for (int i = 0; i < (int)info->dlpi_phnum; i++) {
551 const Elf_Phdr *phdr = &info->dlpi_phdr[i];
552 if (phdr->p_type == PT_LOAD) {
553 uptr cur_beg = info->dlpi_addr + phdr->p_vaddr;
554 uptr cur_end = cur_beg + phdr->p_memsz;
555 bool executable = phdr->p_flags & PF_X;
556 bool writable = phdr->p_flags & PF_W;
557 cur_module.addAddressRange(cur_beg, cur_end, executable,
561 data->modules->push_back(cur_module);
565 #if SANITIZER_ANDROID && __ANDROID_API__ < 21
566 extern "C" __attribute__((weak)) int dl_iterate_phdr(
567 int (*)(struct dl_phdr_info *, size_t, void *), void *);
570 static bool requiresProcmaps() {
571 #if SANITIZER_ANDROID && __ANDROID_API__ <= 22
572 // Fall back to /proc/maps if dl_iterate_phdr is unavailable or broken.
573 // The runtime check allows the same library to work with
574 // both K and L (and future) Android releases.
575 return AndroidGetApiLevel() <= ANDROID_LOLLIPOP_MR1;
581 static void procmapsInit(InternalMmapVectorNoCtor<LoadedModule> *modules) {
582 MemoryMappingLayout memory_mapping(/*cache_enabled*/true);
583 memory_mapping.DumpListOfModules(modules);
586 void ListOfModules::init() {
588 if (requiresProcmaps()) {
589 procmapsInit(&modules_);
591 DlIteratePhdrData data = {&modules_, true};
592 dl_iterate_phdr(dl_iterate_phdr_cb, &data);
596 // When a custom loader is used, dl_iterate_phdr may not contain the full
597 // list of modules. Allow callers to fall back to using procmaps.
598 void ListOfModules::fallbackInit() {
599 if (!requiresProcmaps()) {
601 procmapsInit(&modules_);
607 // getrusage does not give us the current RSS, only the max RSS.
608 // Still, this is better than nothing if /proc/self/statm is not available
609 // for some reason, e.g. due to a sandbox.
610 static uptr GetRSSFromGetrusage() {
612 if (getrusage(RUSAGE_SELF, &usage)) // Failed, probably due to a sandbox.
614 return usage.ru_maxrss << 10; // ru_maxrss is in Kb.
618 if (!common_flags()->can_use_proc_maps_statm)
619 return GetRSSFromGetrusage();
620 fd_t fd = OpenFile("/proc/self/statm", RdOnly);
621 if (fd == kInvalidFd)
622 return GetRSSFromGetrusage();
624 uptr len = internal_read(fd, buf, sizeof(buf) - 1);
629 // The format of the file is:
630 // 1084 89 69 11 0 79 0
631 // We need the second number which is RSS in pages.
633 // Skip the first number.
634 while (*pos >= '0' && *pos <= '9')
637 while (!(*pos >= '0' && *pos <= '9') && *pos != 0)
641 while (*pos >= '0' && *pos <= '9')
642 rss = rss * 10 + *pos++ - '0';
643 return rss * GetPageSizeCached();
646 // sysconf(_SC_NPROCESSORS_{CONF,ONLN}) cannot be used on most platforms as
647 // they allocate memory.
648 u32 GetNumberOfCPUs() {
649 #if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_OPENBSD
652 uptr len = sizeof(ncpu);
655 CHECK_EQ(internal_sysctl(req, 2, &ncpu, &len, NULL, 0), 0);
657 #elif SANITIZER_ANDROID && !defined(CPU_COUNT) && !defined(__aarch64__)
658 // Fall back to /sys/devices/system/cpu on Android when cpu_set_t doesn't
659 // exist in sched.h. That is the case for toolchains generated with older
661 // This code doesn't work on AArch64 because internal_getdents makes use of
662 // the 64bit getdents syscall, but cpu_set_t seems to always exist on AArch64.
663 uptr fd = internal_open("/sys/devices/system/cpu", O_RDONLY | O_DIRECTORY);
664 if (internal_iserror(fd))
666 InternalMmapVector<u8> buffer(4096);
667 uptr bytes_read = buffer.size();
670 struct linux_dirent *entry = (struct linux_dirent *)&buffer[bytes_read];
672 if ((u8 *)entry >= &buffer[bytes_read]) {
673 bytes_read = internal_getdents(fd, (struct linux_dirent *)buffer.data(),
675 if (internal_iserror(bytes_read) || !bytes_read)
677 entry = (struct linux_dirent *)buffer.data();
679 d_type = (u8 *)entry + entry->d_reclen - 1;
680 if (d_type >= &buffer[bytes_read] ||
681 (u8 *)&entry->d_name[3] >= &buffer[bytes_read])
683 if (entry->d_ino != 0 && *d_type == DT_DIR) {
684 if (entry->d_name[0] == 'c' && entry->d_name[1] == 'p' &&
685 entry->d_name[2] == 'u' &&
686 entry->d_name[3] >= '0' && entry->d_name[3] <= '9')
689 entry = (struct linux_dirent *)(((u8 *)entry) + entry->d_reclen);
693 #elif SANITIZER_SOLARIS
694 return sysconf(_SC_NPROCESSORS_ONLN);
697 CHECK_EQ(sched_getaffinity(0, sizeof(cpu_set_t), &CPUs), 0);
698 return CPU_COUNT(&CPUs);
704 # if SANITIZER_ANDROID
705 static atomic_uint8_t android_log_initialized;
707 void AndroidLogInit() {
708 openlog(GetProcessName(), 0, LOG_USER);
709 atomic_store(&android_log_initialized, 1, memory_order_release);
712 static bool ShouldLogAfterPrintf() {
713 return atomic_load(&android_log_initialized, memory_order_acquire);
716 extern "C" SANITIZER_WEAK_ATTRIBUTE
717 int async_safe_write_log(int pri, const char* tag, const char* msg);
718 extern "C" SANITIZER_WEAK_ATTRIBUTE
719 int __android_log_write(int prio, const char* tag, const char* msg);
721 // ANDROID_LOG_INFO is 4, but can't be resolved at runtime.
722 #define SANITIZER_ANDROID_LOG_INFO 4
724 // async_safe_write_log is a new public version of __libc_write_log that is
725 // used behind syslog. It is preferable to syslog as it will not do any dynamic
726 // memory allocation or formatting.
727 // If the function is not available, syslog is preferred for L+ (it was broken
728 // pre-L) as __android_log_write triggers a racey behavior with the strncpy
729 // interceptor. Fallback to __android_log_write pre-L.
730 void WriteOneLineToSyslog(const char *s) {
731 if (&async_safe_write_log) {
732 async_safe_write_log(SANITIZER_ANDROID_LOG_INFO, GetProcessName(), s);
733 } else if (AndroidGetApiLevel() > ANDROID_KITKAT) {
734 syslog(LOG_INFO, "%s", s);
736 CHECK(&__android_log_write);
737 __android_log_write(SANITIZER_ANDROID_LOG_INFO, nullptr, s);
741 extern "C" SANITIZER_WEAK_ATTRIBUTE
742 void android_set_abort_message(const char *);
744 void SetAbortMessage(const char *str) {
745 if (&android_set_abort_message)
746 android_set_abort_message(str);
749 void AndroidLogInit() {}
751 static bool ShouldLogAfterPrintf() { return true; }
753 void WriteOneLineToSyslog(const char *s) { syslog(LOG_INFO, "%s", s); }
755 void SetAbortMessage(const char *str) {}
756 # endif // SANITIZER_ANDROID
758 void LogMessageOnPrintf(const char *str) {
759 if (common_flags()->log_to_syslog && ShouldLogAfterPrintf())
763 #endif // SANITIZER_LINUX
765 #if SANITIZER_LINUX && !SANITIZER_GO
766 // glibc crashes when using clock_gettime from a preinit_array function as the
767 // vDSO function pointers haven't been initialized yet. __progname is
768 // initialized after the vDSO function pointers, so if it exists, is not null
769 // and is not empty, we can use clock_gettime.
770 extern "C" SANITIZER_WEAK_ATTRIBUTE char *__progname;
771 INLINE bool CanUseVDSO() {
772 // Bionic is safe, it checks for the vDSO function pointers to be initialized.
773 if (SANITIZER_ANDROID)
775 if (&__progname && __progname && *__progname)
780 // MonotonicNanoTime is a timing function that can leverage the vDSO by calling
781 // clock_gettime. real_clock_gettime only exists if clock_gettime is
782 // intercepted, so define it weakly and use it if available.
783 extern "C" SANITIZER_WEAK_ATTRIBUTE
784 int real_clock_gettime(u32 clk_id, void *tp);
785 u64 MonotonicNanoTime() {
788 if (&real_clock_gettime)
789 real_clock_gettime(CLOCK_MONOTONIC, &ts);
791 clock_gettime(CLOCK_MONOTONIC, &ts);
793 internal_clock_gettime(CLOCK_MONOTONIC, &ts);
795 return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
798 // Non-Linux & Go always use the syscall.
799 u64 MonotonicNanoTime() {
801 internal_clock_gettime(CLOCK_MONOTONIC, &ts);
802 return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
804 #endif // SANITIZER_LINUX && !SANITIZER_GO
806 #if !SANITIZER_OPENBSD
808 const char *pathname = "/proc/self/exe";
811 static const int name[] = {
821 if (internal_sysctl(name, ARRAY_SIZE(name), path, &len, NULL, 0) != -1)
823 #elif SANITIZER_SOLARIS
824 pathname = getexecname();
825 CHECK_NE(pathname, NULL);
826 #elif SANITIZER_USE_GETAUXVAL
827 // Calling execve with /proc/self/exe sets that as $EXEC_ORIGIN. Binaries that
828 // rely on that will fail to load shared libraries. Query AT_EXECFN instead.
829 pathname = reinterpret_cast<const char *>(getauxval(AT_EXECFN));
832 uptr rv = internal_execve(pathname, GetArgv(), GetEnviron());
834 CHECK_EQ(internal_iserror(rv, &rverrno), true);
835 Printf("execve failed, errno %d\n", rverrno);
838 #endif // !SANITIZER_OPENBSD
840 } // namespace __sanitizer