xref: /freebsd-src/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp (revision 647cbc5de815c5651677bf8582797f716ec7b48d)
1 //===-- tsan_interceptors_posix.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 a part of ThreadSanitizer (TSan), a race detector.
10 //
11 // FIXME: move as many interceptors as possible into
12 // sanitizer_common/sanitizer_common_interceptors.inc
13 //===----------------------------------------------------------------------===//
14 
15 #include "sanitizer_common/sanitizer_atomic.h"
16 #include "sanitizer_common/sanitizer_errno.h"
17 #include "sanitizer_common/sanitizer_libc.h"
18 #include "sanitizer_common/sanitizer_linux.h"
19 #include "sanitizer_common/sanitizer_platform_limits_netbsd.h"
20 #include "sanitizer_common/sanitizer_platform_limits_posix.h"
21 #include "sanitizer_common/sanitizer_placement_new.h"
22 #include "sanitizer_common/sanitizer_posix.h"
23 #include "sanitizer_common/sanitizer_stacktrace.h"
24 #include "sanitizer_common/sanitizer_tls_get_addr.h"
25 #include "interception/interception.h"
26 #include "tsan_interceptors.h"
27 #include "tsan_interface.h"
28 #include "tsan_platform.h"
29 #include "tsan_suppressions.h"
30 #include "tsan_rtl.h"
31 #include "tsan_mman.h"
32 #include "tsan_fd.h"
33 
34 #include <stdarg.h>
35 
36 using namespace __tsan;
37 
38 DECLARE_REAL(void *, memcpy, void *to, const void *from, SIZE_T size)
39 DECLARE_REAL(void *, memset, void *block, int c, SIZE_T size)
40 
41 #if SANITIZER_FREEBSD || SANITIZER_APPLE
42 #define stdout __stdoutp
43 #define stderr __stderrp
44 #endif
45 
46 #if SANITIZER_NETBSD
47 #define dirfd(dirp) (*(int *)(dirp))
48 #define fileno_unlocked(fp)              \
49   (((__sanitizer_FILE *)fp)->_file == -1 \
50        ? -1                              \
51        : (int)(unsigned short)(((__sanitizer_FILE *)fp)->_file))
52 
53 #define stdout ((__sanitizer_FILE*)&__sF[1])
54 #define stderr ((__sanitizer_FILE*)&__sF[2])
55 
56 #define nanosleep __nanosleep50
57 #define vfork __vfork14
58 #endif
59 
60 #ifdef __mips__
61 const int kSigCount = 129;
62 #else
63 const int kSigCount = 65;
64 #endif
65 
66 #ifdef __mips__
67 struct ucontext_t {
68   u64 opaque[768 / sizeof(u64) + 1];
69 };
70 #else
71 struct ucontext_t {
72   // The size is determined by looking at sizeof of real ucontext_t on linux.
73   u64 opaque[936 / sizeof(u64) + 1];
74 };
75 #endif
76 
77 #if defined(__x86_64__) || defined(__mips__) || SANITIZER_PPC64V1 || \
78     defined(__s390x__)
79 #define PTHREAD_ABI_BASE  "GLIBC_2.3.2"
80 #elif defined(__aarch64__) || SANITIZER_PPC64V2
81 #define PTHREAD_ABI_BASE  "GLIBC_2.17"
82 #elif SANITIZER_LOONGARCH64
83 #define PTHREAD_ABI_BASE  "GLIBC_2.36"
84 #elif SANITIZER_RISCV64
85 #  define PTHREAD_ABI_BASE "GLIBC_2.27"
86 #endif
87 
88 extern "C" int pthread_attr_init(void *attr);
89 extern "C" int pthread_attr_destroy(void *attr);
90 DECLARE_REAL(int, pthread_attr_getdetachstate, void *, void *)
91 extern "C" int pthread_attr_setstacksize(void *attr, uptr stacksize);
92 extern "C" int pthread_atfork(void (*prepare)(void), void (*parent)(void),
93                               void (*child)(void));
94 extern "C" int pthread_key_create(unsigned *key, void (*destructor)(void* v));
95 extern "C" int pthread_setspecific(unsigned key, const void *v);
96 DECLARE_REAL(int, pthread_mutexattr_gettype, void *, void *)
97 DECLARE_REAL(int, fflush, __sanitizer_FILE *fp)
98 DECLARE_REAL_AND_INTERCEPTOR(void *, malloc, uptr size)
99 DECLARE_REAL_AND_INTERCEPTOR(void, free, void *ptr)
100 extern "C" int pthread_equal(void *t1, void *t2);
101 extern "C" void *pthread_self();
102 extern "C" void _exit(int status);
103 #if !SANITIZER_NETBSD
104 extern "C" int fileno_unlocked(void *stream);
105 extern "C" int dirfd(void *dirp);
106 #endif
107 #if SANITIZER_NETBSD
108 extern __sanitizer_FILE __sF[];
109 #else
110 extern __sanitizer_FILE *stdout, *stderr;
111 #endif
112 #if !SANITIZER_FREEBSD && !SANITIZER_APPLE && !SANITIZER_NETBSD
113 const int PTHREAD_MUTEX_RECURSIVE = 1;
114 const int PTHREAD_MUTEX_RECURSIVE_NP = 1;
115 #else
116 const int PTHREAD_MUTEX_RECURSIVE = 2;
117 const int PTHREAD_MUTEX_RECURSIVE_NP = 2;
118 #endif
119 #if !SANITIZER_FREEBSD && !SANITIZER_APPLE && !SANITIZER_NETBSD
120 const int EPOLL_CTL_ADD = 1;
121 #endif
122 const int SIGILL = 4;
123 const int SIGTRAP = 5;
124 const int SIGABRT = 6;
125 const int SIGFPE = 8;
126 const int SIGSEGV = 11;
127 const int SIGPIPE = 13;
128 const int SIGTERM = 15;
129 #if defined(__mips__) || SANITIZER_FREEBSD || SANITIZER_APPLE || SANITIZER_NETBSD
130 const int SIGBUS = 10;
131 const int SIGSYS = 12;
132 #else
133 const int SIGBUS = 7;
134 const int SIGSYS = 31;
135 #endif
136 #if SANITIZER_HAS_SIGINFO
137 const int SI_TIMER = -2;
138 #endif
139 void *const MAP_FAILED = (void*)-1;
140 #if SANITIZER_NETBSD
141 const int PTHREAD_BARRIER_SERIAL_THREAD = 1234567;
142 #elif !SANITIZER_APPLE
143 const int PTHREAD_BARRIER_SERIAL_THREAD = -1;
144 #endif
145 const int MAP_FIXED = 0x10;
146 typedef long long_t;
147 typedef __sanitizer::u16 mode_t;
148 
149 // From /usr/include/unistd.h
150 # define F_ULOCK 0      /* Unlock a previously locked region.  */
151 # define F_LOCK  1      /* Lock a region for exclusive use.  */
152 # define F_TLOCK 2      /* Test and lock a region for exclusive use.  */
153 # define F_TEST  3      /* Test a region for other processes locks.  */
154 
155 #if SANITIZER_FREEBSD || SANITIZER_APPLE || SANITIZER_NETBSD
156 const int SA_SIGINFO = 0x40;
157 const int SIG_SETMASK = 3;
158 #elif defined(__mips__)
159 const int SA_SIGINFO = 8;
160 const int SIG_SETMASK = 3;
161 #else
162 const int SA_SIGINFO = 4;
163 const int SIG_SETMASK = 2;
164 #endif
165 
166 namespace __tsan {
167 struct SignalDesc {
168   bool armed;
169   __sanitizer_siginfo siginfo;
170   ucontext_t ctx;
171 };
172 
173 struct ThreadSignalContext {
174   int int_signal_send;
175   SignalDesc pending_signals[kSigCount];
176   // emptyset and oldset are too big for stack.
177   __sanitizer_sigset_t emptyset;
178   __sanitizer_sigset_t oldset;
179 };
180 
181 void EnterBlockingFunc(ThreadState *thr) {
182   for (;;) {
183     // The order is important to not delay a signal infinitely if it's
184     // delivered right before we set in_blocking_func. Note: we can't call
185     // ProcessPendingSignals when in_blocking_func is set, or we can handle
186     // a signal synchronously when we are already handling a signal.
187     atomic_store(&thr->in_blocking_func, 1, memory_order_relaxed);
188     if (atomic_load(&thr->pending_signals, memory_order_relaxed) == 0)
189       break;
190     atomic_store(&thr->in_blocking_func, 0, memory_order_relaxed);
191     ProcessPendingSignals(thr);
192   }
193 }
194 
195 // The sole reason tsan wraps atexit callbacks is to establish synchronization
196 // between callback setup and callback execution.
197 struct AtExitCtx {
198   void (*f)();
199   void *arg;
200   uptr pc;
201 };
202 
203 // InterceptorContext holds all global data required for interceptors.
204 // It's explicitly constructed in InitializeInterceptors with placement new
205 // and is never destroyed. This allows usage of members with non-trivial
206 // constructors and destructors.
207 struct InterceptorContext {
208   // The object is 64-byte aligned, because we want hot data to be located
209   // in a single cache line if possible (it's accessed in every interceptor).
210   ALIGNED(64) LibIgnore libignore;
211   __sanitizer_sigaction sigactions[kSigCount];
212 #if !SANITIZER_APPLE && !SANITIZER_NETBSD
213   unsigned finalize_key;
214 #endif
215 
216   Mutex atexit_mu;
217   Vector<struct AtExitCtx *> AtExitStack;
218 
219   InterceptorContext() : libignore(LINKER_INITIALIZED), atexit_mu(MutexTypeAtExit), AtExitStack() {}
220 };
221 
222 static ALIGNED(64) char interceptor_placeholder[sizeof(InterceptorContext)];
223 InterceptorContext *interceptor_ctx() {
224   return reinterpret_cast<InterceptorContext*>(&interceptor_placeholder[0]);
225 }
226 
227 LibIgnore *libignore() {
228   return &interceptor_ctx()->libignore;
229 }
230 
231 void InitializeLibIgnore() {
232   const SuppressionContext &supp = *Suppressions();
233   const uptr n = supp.SuppressionCount();
234   for (uptr i = 0; i < n; i++) {
235     const Suppression *s = supp.SuppressionAt(i);
236     if (0 == internal_strcmp(s->type, kSuppressionLib))
237       libignore()->AddIgnoredLibrary(s->templ);
238   }
239   if (flags()->ignore_noninstrumented_modules)
240     libignore()->IgnoreNoninstrumentedModules(true);
241   libignore()->OnLibraryLoaded(0);
242 }
243 
244 // The following two hooks can be used by for cooperative scheduling when
245 // locking.
246 #ifdef TSAN_EXTERNAL_HOOKS
247 void OnPotentiallyBlockingRegionBegin();
248 void OnPotentiallyBlockingRegionEnd();
249 #else
250 SANITIZER_WEAK_CXX_DEFAULT_IMPL void OnPotentiallyBlockingRegionBegin() {}
251 SANITIZER_WEAK_CXX_DEFAULT_IMPL void OnPotentiallyBlockingRegionEnd() {}
252 #endif
253 
254 }  // namespace __tsan
255 
256 static ThreadSignalContext *SigCtx(ThreadState *thr) {
257   // This function may be called reentrantly if it is interrupted by a signal
258   // handler. Use CAS to handle the race.
259   uptr ctx = atomic_load(&thr->signal_ctx, memory_order_relaxed);
260   if (ctx == 0 && !thr->is_dead) {
261     uptr pctx =
262         (uptr)MmapOrDie(sizeof(ThreadSignalContext), "ThreadSignalContext");
263     MemoryResetRange(thr, (uptr)&SigCtx, pctx, sizeof(ThreadSignalContext));
264     if (atomic_compare_exchange_strong(&thr->signal_ctx, &ctx, pctx,
265                                        memory_order_relaxed)) {
266       ctx = pctx;
267     } else {
268       UnmapOrDie((ThreadSignalContext *)pctx, sizeof(ThreadSignalContext));
269     }
270   }
271   return (ThreadSignalContext *)ctx;
272 }
273 
274 ScopedInterceptor::ScopedInterceptor(ThreadState *thr, const char *fname,
275                                      uptr pc)
276     : thr_(thr) {
277   LazyInitialize(thr);
278   if (UNLIKELY(atomic_load(&thr->in_blocking_func, memory_order_relaxed))) {
279     // pthread_join is marked as blocking, but it's also known to call other
280     // intercepted functions (mmap, free). If we don't reset in_blocking_func
281     // we can get deadlocks and memory corruptions if we deliver a synchronous
282     // signal inside of an mmap/free interceptor.
283     // So reset it and restore it back in the destructor.
284     // See https://github.com/google/sanitizers/issues/1540
285     atomic_store(&thr->in_blocking_func, 0, memory_order_relaxed);
286     in_blocking_func_ = true;
287   }
288   if (!thr_->is_inited) return;
289   if (!thr_->ignore_interceptors) FuncEntry(thr, pc);
290   DPrintf("#%d: intercept %s()\n", thr_->tid, fname);
291   ignoring_ =
292       !thr_->in_ignored_lib && (flags()->ignore_interceptors_accesses ||
293                                 libignore()->IsIgnored(pc, &in_ignored_lib_));
294   EnableIgnores();
295 }
296 
297 ScopedInterceptor::~ScopedInterceptor() {
298   if (!thr_->is_inited) return;
299   DisableIgnores();
300   if (UNLIKELY(in_blocking_func_))
301     EnterBlockingFunc(thr_);
302   if (!thr_->ignore_interceptors) {
303     ProcessPendingSignals(thr_);
304     FuncExit(thr_);
305     CheckedMutex::CheckNoLocks();
306   }
307 }
308 
309 NOINLINE
310 void ScopedInterceptor::EnableIgnoresImpl() {
311   ThreadIgnoreBegin(thr_, 0);
312   if (flags()->ignore_noninstrumented_modules)
313     thr_->suppress_reports++;
314   if (in_ignored_lib_) {
315     DCHECK(!thr_->in_ignored_lib);
316     thr_->in_ignored_lib = true;
317   }
318 }
319 
320 NOINLINE
321 void ScopedInterceptor::DisableIgnoresImpl() {
322   ThreadIgnoreEnd(thr_);
323   if (flags()->ignore_noninstrumented_modules)
324     thr_->suppress_reports--;
325   if (in_ignored_lib_) {
326     DCHECK(thr_->in_ignored_lib);
327     thr_->in_ignored_lib = false;
328   }
329 }
330 
331 #define TSAN_INTERCEPT(func) INTERCEPT_FUNCTION(func)
332 #if SANITIZER_FREEBSD || SANITIZER_NETBSD
333 #  define TSAN_INTERCEPT_VER(func, ver) INTERCEPT_FUNCTION(func)
334 #else
335 #  define TSAN_INTERCEPT_VER(func, ver) INTERCEPT_FUNCTION_VER(func, ver)
336 #endif
337 #if SANITIZER_FREEBSD
338 #  define TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(func) \
339     INTERCEPT_FUNCTION(_pthread_##func)
340 #else
341 #  define TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(func)
342 #endif
343 #if SANITIZER_NETBSD
344 #  define TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(func) \
345     INTERCEPT_FUNCTION(__libc_##func)
346 #  define TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS_THR(func) \
347     INTERCEPT_FUNCTION(__libc_thr_##func)
348 #else
349 #  define TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(func)
350 #  define TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS_THR(func)
351 #endif
352 
353 #define READ_STRING_OF_LEN(thr, pc, s, len, n)                 \
354   MemoryAccessRange((thr), (pc), (uptr)(s),                         \
355     common_flags()->strict_string_checks ? (len) + 1 : (n), false)
356 
357 #define READ_STRING(thr, pc, s, n)                             \
358     READ_STRING_OF_LEN((thr), (pc), (s), internal_strlen(s), (n))
359 
360 #define BLOCK_REAL(name) (BlockingCall(thr), REAL(name))
361 
362 struct BlockingCall {
363   explicit BlockingCall(ThreadState *thr)
364       : thr(thr) {
365     EnterBlockingFunc(thr);
366     // When we are in a "blocking call", we process signals asynchronously
367     // (right when they arrive). In this context we do not expect to be
368     // executing any user/runtime code. The known interceptor sequence when
369     // this is not true is: pthread_join -> munmap(stack). It's fine
370     // to ignore munmap in this case -- we handle stack shadow separately.
371     thr->ignore_interceptors++;
372   }
373 
374   ~BlockingCall() {
375     thr->ignore_interceptors--;
376     atomic_store(&thr->in_blocking_func, 0, memory_order_relaxed);
377   }
378 
379   ThreadState *thr;
380 };
381 
382 TSAN_INTERCEPTOR(unsigned, sleep, unsigned sec) {
383   SCOPED_TSAN_INTERCEPTOR(sleep, sec);
384   unsigned res = BLOCK_REAL(sleep)(sec);
385   AfterSleep(thr, pc);
386   return res;
387 }
388 
389 TSAN_INTERCEPTOR(int, usleep, long_t usec) {
390   SCOPED_TSAN_INTERCEPTOR(usleep, usec);
391   int res = BLOCK_REAL(usleep)(usec);
392   AfterSleep(thr, pc);
393   return res;
394 }
395 
396 TSAN_INTERCEPTOR(int, nanosleep, void *req, void *rem) {
397   SCOPED_TSAN_INTERCEPTOR(nanosleep, req, rem);
398   int res = BLOCK_REAL(nanosleep)(req, rem);
399   AfterSleep(thr, pc);
400   return res;
401 }
402 
403 TSAN_INTERCEPTOR(int, pause, int fake) {
404   SCOPED_TSAN_INTERCEPTOR(pause, fake);
405   return BLOCK_REAL(pause)(fake);
406 }
407 
408 // Note: we specifically call the function in such strange way
409 // with "installed_at" because in reports it will appear between
410 // callback frames and the frame that installed the callback.
411 static void at_exit_callback_installed_at() {
412   AtExitCtx *ctx;
413   {
414     // Ensure thread-safety.
415     Lock l(&interceptor_ctx()->atexit_mu);
416 
417     // Pop AtExitCtx from the top of the stack of callback functions
418     uptr element = interceptor_ctx()->AtExitStack.Size() - 1;
419     ctx = interceptor_ctx()->AtExitStack[element];
420     interceptor_ctx()->AtExitStack.PopBack();
421   }
422 
423   ThreadState *thr = cur_thread();
424   Acquire(thr, ctx->pc, (uptr)ctx);
425   FuncEntry(thr, ctx->pc);
426   ((void(*)())ctx->f)();
427   FuncExit(thr);
428   Free(ctx);
429 }
430 
431 static void cxa_at_exit_callback_installed_at(void *arg) {
432   ThreadState *thr = cur_thread();
433   AtExitCtx *ctx = (AtExitCtx*)arg;
434   Acquire(thr, ctx->pc, (uptr)arg);
435   FuncEntry(thr, ctx->pc);
436   ((void(*)(void *arg))ctx->f)(ctx->arg);
437   FuncExit(thr);
438   Free(ctx);
439 }
440 
441 static int setup_at_exit_wrapper(ThreadState *thr, uptr pc, void(*f)(),
442       void *arg, void *dso);
443 
444 #if !SANITIZER_ANDROID
445 TSAN_INTERCEPTOR(int, atexit, void (*f)()) {
446   if (in_symbolizer())
447     return 0;
448   // We want to setup the atexit callback even if we are in ignored lib
449   // or after fork.
450   SCOPED_INTERCEPTOR_RAW(atexit, f);
451   return setup_at_exit_wrapper(thr, GET_CALLER_PC(), (void (*)())f, 0, 0);
452 }
453 #endif
454 
455 TSAN_INTERCEPTOR(int, __cxa_atexit, void (*f)(void *a), void *arg, void *dso) {
456   if (in_symbolizer())
457     return 0;
458   SCOPED_TSAN_INTERCEPTOR(__cxa_atexit, f, arg, dso);
459   return setup_at_exit_wrapper(thr, GET_CALLER_PC(), (void (*)())f, arg, dso);
460 }
461 
462 static int setup_at_exit_wrapper(ThreadState *thr, uptr pc, void(*f)(),
463       void *arg, void *dso) {
464   auto *ctx = New<AtExitCtx>();
465   ctx->f = f;
466   ctx->arg = arg;
467   ctx->pc = pc;
468   Release(thr, pc, (uptr)ctx);
469   // Memory allocation in __cxa_atexit will race with free during exit,
470   // because we do not see synchronization around atexit callback list.
471   ThreadIgnoreBegin(thr, pc);
472   int res;
473   if (!dso) {
474     // NetBSD does not preserve the 2nd argument if dso is equal to 0
475     // Store ctx in a local stack-like structure
476 
477     // Ensure thread-safety.
478     Lock l(&interceptor_ctx()->atexit_mu);
479     // __cxa_atexit calls calloc. If we don't ignore interceptors, we will fail
480     // due to atexit_mu held on exit from the calloc interceptor.
481     ScopedIgnoreInterceptors ignore;
482 
483     res = REAL(__cxa_atexit)((void (*)(void *a))at_exit_callback_installed_at,
484                              0, 0);
485     // Push AtExitCtx on the top of the stack of callback functions
486     if (!res) {
487       interceptor_ctx()->AtExitStack.PushBack(ctx);
488     }
489   } else {
490     res = REAL(__cxa_atexit)(cxa_at_exit_callback_installed_at, ctx, dso);
491   }
492   ThreadIgnoreEnd(thr);
493   return res;
494 }
495 
496 #if !SANITIZER_APPLE && !SANITIZER_NETBSD
497 static void on_exit_callback_installed_at(int status, void *arg) {
498   ThreadState *thr = cur_thread();
499   AtExitCtx *ctx = (AtExitCtx*)arg;
500   Acquire(thr, ctx->pc, (uptr)arg);
501   FuncEntry(thr, ctx->pc);
502   ((void(*)(int status, void *arg))ctx->f)(status, ctx->arg);
503   FuncExit(thr);
504   Free(ctx);
505 }
506 
507 TSAN_INTERCEPTOR(int, on_exit, void(*f)(int, void*), void *arg) {
508   if (in_symbolizer())
509     return 0;
510   SCOPED_TSAN_INTERCEPTOR(on_exit, f, arg);
511   auto *ctx = New<AtExitCtx>();
512   ctx->f = (void(*)())f;
513   ctx->arg = arg;
514   ctx->pc = GET_CALLER_PC();
515   Release(thr, pc, (uptr)ctx);
516   // Memory allocation in __cxa_atexit will race with free during exit,
517   // because we do not see synchronization around atexit callback list.
518   ThreadIgnoreBegin(thr, pc);
519   int res = REAL(on_exit)(on_exit_callback_installed_at, ctx);
520   ThreadIgnoreEnd(thr);
521   return res;
522 }
523 #define TSAN_MAYBE_INTERCEPT_ON_EXIT TSAN_INTERCEPT(on_exit)
524 #else
525 #define TSAN_MAYBE_INTERCEPT_ON_EXIT
526 #endif
527 
528 // Cleanup old bufs.
529 static void JmpBufGarbageCollect(ThreadState *thr, uptr sp) {
530   for (uptr i = 0; i < thr->jmp_bufs.Size(); i++) {
531     JmpBuf *buf = &thr->jmp_bufs[i];
532     if (buf->sp <= sp) {
533       uptr sz = thr->jmp_bufs.Size();
534       internal_memcpy(buf, &thr->jmp_bufs[sz - 1], sizeof(*buf));
535       thr->jmp_bufs.PopBack();
536       i--;
537     }
538   }
539 }
540 
541 static void SetJmp(ThreadState *thr, uptr sp) {
542   if (!thr->is_inited)  // called from libc guts during bootstrap
543     return;
544   // Cleanup old bufs.
545   JmpBufGarbageCollect(thr, sp);
546   // Remember the buf.
547   JmpBuf *buf = thr->jmp_bufs.PushBack();
548   buf->sp = sp;
549   buf->shadow_stack_pos = thr->shadow_stack_pos;
550   ThreadSignalContext *sctx = SigCtx(thr);
551   buf->int_signal_send = sctx ? sctx->int_signal_send : 0;
552   buf->in_blocking_func = atomic_load(&thr->in_blocking_func, memory_order_relaxed);
553   buf->in_signal_handler = atomic_load(&thr->in_signal_handler,
554       memory_order_relaxed);
555 }
556 
557 static void LongJmp(ThreadState *thr, uptr *env) {
558   uptr sp = ExtractLongJmpSp(env);
559   // Find the saved buf with matching sp.
560   for (uptr i = 0; i < thr->jmp_bufs.Size(); i++) {
561     JmpBuf *buf = &thr->jmp_bufs[i];
562     if (buf->sp == sp) {
563       CHECK_GE(thr->shadow_stack_pos, buf->shadow_stack_pos);
564       // Unwind the stack.
565       while (thr->shadow_stack_pos > buf->shadow_stack_pos)
566         FuncExit(thr);
567       ThreadSignalContext *sctx = SigCtx(thr);
568       if (sctx)
569         sctx->int_signal_send = buf->int_signal_send;
570       atomic_store(&thr->in_blocking_func, buf->in_blocking_func,
571           memory_order_relaxed);
572       atomic_store(&thr->in_signal_handler, buf->in_signal_handler,
573           memory_order_relaxed);
574       JmpBufGarbageCollect(thr, buf->sp - 1);  // do not collect buf->sp
575       return;
576     }
577   }
578   Printf("ThreadSanitizer: can't find longjmp buf\n");
579   CHECK(0);
580 }
581 
582 // FIXME: put everything below into a common extern "C" block?
583 extern "C" void __tsan_setjmp(uptr sp) { SetJmp(cur_thread_init(), sp); }
584 
585 #if SANITIZER_APPLE
586 TSAN_INTERCEPTOR(int, setjmp, void *env);
587 TSAN_INTERCEPTOR(int, _setjmp, void *env);
588 TSAN_INTERCEPTOR(int, sigsetjmp, void *env);
589 #else  // SANITIZER_APPLE
590 
591 #if SANITIZER_NETBSD
592 #define setjmp_symname __setjmp14
593 #define sigsetjmp_symname __sigsetjmp14
594 #else
595 #define setjmp_symname setjmp
596 #define sigsetjmp_symname sigsetjmp
597 #endif
598 
599 DEFINE_REAL(int, setjmp_symname, void *env)
600 DEFINE_REAL(int, _setjmp, void *env)
601 DEFINE_REAL(int, sigsetjmp_symname, void *env)
602 #if !SANITIZER_NETBSD
603 DEFINE_REAL(int, __sigsetjmp, void *env)
604 #endif
605 
606 // The real interceptor for setjmp is special, and implemented in pure asm. We
607 // just need to initialize the REAL functions so that they can be used in asm.
608 static void InitializeSetjmpInterceptors() {
609   // We can not use TSAN_INTERCEPT to get setjmp addr, because it does &setjmp and
610   // setjmp is not present in some versions of libc.
611   using __interception::InterceptFunction;
612   InterceptFunction(SANITIZER_STRINGIFY(setjmp_symname), (uptr*)&REAL(setjmp_symname), 0, 0);
613   InterceptFunction("_setjmp", (uptr*)&REAL(_setjmp), 0, 0);
614   InterceptFunction(SANITIZER_STRINGIFY(sigsetjmp_symname), (uptr*)&REAL(sigsetjmp_symname), 0,
615                     0);
616 #if !SANITIZER_NETBSD
617   InterceptFunction("__sigsetjmp", (uptr*)&REAL(__sigsetjmp), 0, 0);
618 #endif
619 }
620 #endif  // SANITIZER_APPLE
621 
622 #if SANITIZER_NETBSD
623 #define longjmp_symname __longjmp14
624 #define siglongjmp_symname __siglongjmp14
625 #else
626 #define longjmp_symname longjmp
627 #define siglongjmp_symname siglongjmp
628 #endif
629 
630 TSAN_INTERCEPTOR(void, longjmp_symname, uptr *env, int val) {
631   // Note: if we call REAL(longjmp) in the context of ScopedInterceptor,
632   // bad things will happen. We will jump over ScopedInterceptor dtor and can
633   // leave thr->in_ignored_lib set.
634   {
635     SCOPED_INTERCEPTOR_RAW(longjmp_symname, env, val);
636   }
637   LongJmp(cur_thread(), env);
638   REAL(longjmp_symname)(env, val);
639 }
640 
641 TSAN_INTERCEPTOR(void, siglongjmp_symname, uptr *env, int val) {
642   {
643     SCOPED_INTERCEPTOR_RAW(siglongjmp_symname, env, val);
644   }
645   LongJmp(cur_thread(), env);
646   REAL(siglongjmp_symname)(env, val);
647 }
648 
649 #if SANITIZER_NETBSD
650 TSAN_INTERCEPTOR(void, _longjmp, uptr *env, int val) {
651   {
652     SCOPED_INTERCEPTOR_RAW(_longjmp, env, val);
653   }
654   LongJmp(cur_thread(), env);
655   REAL(_longjmp)(env, val);
656 }
657 #endif
658 
659 #if !SANITIZER_APPLE
660 TSAN_INTERCEPTOR(void*, malloc, uptr size) {
661   if (in_symbolizer())
662     return InternalAlloc(size);
663   void *p = 0;
664   {
665     SCOPED_INTERCEPTOR_RAW(malloc, size);
666     p = user_alloc(thr, pc, size);
667   }
668   invoke_malloc_hook(p, size);
669   return p;
670 }
671 
672 // In glibc<2.25, dynamic TLS blocks are allocated by __libc_memalign. Intercept
673 // __libc_memalign so that (1) we can detect races (2) free will not be called
674 // on libc internally allocated blocks.
675 TSAN_INTERCEPTOR(void*, __libc_memalign, uptr align, uptr sz) {
676   SCOPED_INTERCEPTOR_RAW(__libc_memalign, align, sz);
677   return user_memalign(thr, pc, align, sz);
678 }
679 
680 TSAN_INTERCEPTOR(void*, calloc, uptr size, uptr n) {
681   if (in_symbolizer())
682     return InternalCalloc(size, n);
683   void *p = 0;
684   {
685     SCOPED_INTERCEPTOR_RAW(calloc, size, n);
686     p = user_calloc(thr, pc, size, n);
687   }
688   invoke_malloc_hook(p, n * size);
689   return p;
690 }
691 
692 TSAN_INTERCEPTOR(void*, realloc, void *p, uptr size) {
693   if (in_symbolizer())
694     return InternalRealloc(p, size);
695   if (p)
696     invoke_free_hook(p);
697   {
698     SCOPED_INTERCEPTOR_RAW(realloc, p, size);
699     p = user_realloc(thr, pc, p, size);
700   }
701   invoke_malloc_hook(p, size);
702   return p;
703 }
704 
705 TSAN_INTERCEPTOR(void*, reallocarray, void *p, uptr size, uptr n) {
706   if (in_symbolizer())
707     return InternalReallocArray(p, size, n);
708   if (p)
709     invoke_free_hook(p);
710   {
711     SCOPED_INTERCEPTOR_RAW(reallocarray, p, size, n);
712     p = user_reallocarray(thr, pc, p, size, n);
713   }
714   invoke_malloc_hook(p, size);
715   return p;
716 }
717 
718 TSAN_INTERCEPTOR(void, free, void *p) {
719   if (p == 0)
720     return;
721   if (in_symbolizer())
722     return InternalFree(p);
723   invoke_free_hook(p);
724   SCOPED_INTERCEPTOR_RAW(free, p);
725   user_free(thr, pc, p);
726 }
727 
728 TSAN_INTERCEPTOR(void, cfree, void *p) {
729   if (p == 0)
730     return;
731   if (in_symbolizer())
732     return InternalFree(p);
733   invoke_free_hook(p);
734   SCOPED_INTERCEPTOR_RAW(cfree, p);
735   user_free(thr, pc, p);
736 }
737 
738 TSAN_INTERCEPTOR(uptr, malloc_usable_size, void *p) {
739   SCOPED_INTERCEPTOR_RAW(malloc_usable_size, p);
740   return user_alloc_usable_size(p);
741 }
742 #endif
743 
744 TSAN_INTERCEPTOR(char *, strcpy, char *dst, const char *src) {
745   SCOPED_TSAN_INTERCEPTOR(strcpy, dst, src);
746   uptr srclen = internal_strlen(src);
747   MemoryAccessRange(thr, pc, (uptr)dst, srclen + 1, true);
748   MemoryAccessRange(thr, pc, (uptr)src, srclen + 1, false);
749   return REAL(strcpy)(dst, src);
750 }
751 
752 TSAN_INTERCEPTOR(char*, strncpy, char *dst, char *src, uptr n) {
753   SCOPED_TSAN_INTERCEPTOR(strncpy, dst, src, n);
754   uptr srclen = internal_strnlen(src, n);
755   MemoryAccessRange(thr, pc, (uptr)dst, n, true);
756   MemoryAccessRange(thr, pc, (uptr)src, min(srclen + 1, n), false);
757   return REAL(strncpy)(dst, src, n);
758 }
759 
760 TSAN_INTERCEPTOR(char*, strdup, const char *str) {
761   SCOPED_TSAN_INTERCEPTOR(strdup, str);
762   // strdup will call malloc, so no instrumentation is required here.
763   return REAL(strdup)(str);
764 }
765 
766 // Zero out addr if it points into shadow memory and was provided as a hint
767 // only, i.e., MAP_FIXED is not set.
768 static bool fix_mmap_addr(void **addr, long_t sz, int flags) {
769   if (*addr) {
770     if (!IsAppMem((uptr)*addr) || !IsAppMem((uptr)*addr + sz - 1)) {
771       if (flags & MAP_FIXED) {
772         errno = errno_EINVAL;
773         return false;
774       } else {
775         *addr = 0;
776       }
777     }
778   }
779   return true;
780 }
781 
782 template <class Mmap>
783 static void *mmap_interceptor(ThreadState *thr, uptr pc, Mmap real_mmap,
784                               void *addr, SIZE_T sz, int prot, int flags,
785                               int fd, OFF64_T off) {
786   if (!fix_mmap_addr(&addr, sz, flags)) return MAP_FAILED;
787   void *res = real_mmap(addr, sz, prot, flags, fd, off);
788   if (res != MAP_FAILED) {
789     if (!IsAppMem((uptr)res) || !IsAppMem((uptr)res + sz - 1)) {
790       Report("ThreadSanitizer: mmap at bad address: addr=%p size=%p res=%p\n",
791              addr, (void*)sz, res);
792       Die();
793     }
794     if (fd > 0) FdAccess(thr, pc, fd);
795     MemoryRangeImitateWriteOrResetRange(thr, pc, (uptr)res, sz);
796   }
797   return res;
798 }
799 
800 template <class Munmap>
801 static int munmap_interceptor(ThreadState *thr, uptr pc, Munmap real_munmap,
802                                 void *addr, SIZE_T sz) {
803   UnmapShadow(thr, (uptr)addr, sz);
804   int res = real_munmap(addr, sz);
805   return res;
806 }
807 
808 #if SANITIZER_LINUX
809 TSAN_INTERCEPTOR(void*, memalign, uptr align, uptr sz) {
810   SCOPED_INTERCEPTOR_RAW(memalign, align, sz);
811   return user_memalign(thr, pc, align, sz);
812 }
813 #define TSAN_MAYBE_INTERCEPT_MEMALIGN TSAN_INTERCEPT(memalign)
814 #else
815 #define TSAN_MAYBE_INTERCEPT_MEMALIGN
816 #endif
817 
818 #if !SANITIZER_APPLE
819 TSAN_INTERCEPTOR(void*, aligned_alloc, uptr align, uptr sz) {
820   if (in_symbolizer())
821     return InternalAlloc(sz, nullptr, align);
822   SCOPED_INTERCEPTOR_RAW(aligned_alloc, align, sz);
823   return user_aligned_alloc(thr, pc, align, sz);
824 }
825 
826 TSAN_INTERCEPTOR(void*, valloc, uptr sz) {
827   if (in_symbolizer())
828     return InternalAlloc(sz, nullptr, GetPageSizeCached());
829   SCOPED_INTERCEPTOR_RAW(valloc, sz);
830   return user_valloc(thr, pc, sz);
831 }
832 #endif
833 
834 #if SANITIZER_LINUX
835 TSAN_INTERCEPTOR(void*, pvalloc, uptr sz) {
836   if (in_symbolizer()) {
837     uptr PageSize = GetPageSizeCached();
838     sz = sz ? RoundUpTo(sz, PageSize) : PageSize;
839     return InternalAlloc(sz, nullptr, PageSize);
840   }
841   SCOPED_INTERCEPTOR_RAW(pvalloc, sz);
842   return user_pvalloc(thr, pc, sz);
843 }
844 #define TSAN_MAYBE_INTERCEPT_PVALLOC TSAN_INTERCEPT(pvalloc)
845 #else
846 #define TSAN_MAYBE_INTERCEPT_PVALLOC
847 #endif
848 
849 #if !SANITIZER_APPLE
850 TSAN_INTERCEPTOR(int, posix_memalign, void **memptr, uptr align, uptr sz) {
851   if (in_symbolizer()) {
852     void *p = InternalAlloc(sz, nullptr, align);
853     if (!p)
854       return errno_ENOMEM;
855     *memptr = p;
856     return 0;
857   }
858   SCOPED_INTERCEPTOR_RAW(posix_memalign, memptr, align, sz);
859   return user_posix_memalign(thr, pc, memptr, align, sz);
860 }
861 #endif
862 
863 // Both __cxa_guard_acquire and pthread_once 0-initialize
864 // the object initially. pthread_once does not have any
865 // other ABI requirements. __cxa_guard_acquire assumes
866 // that any non-0 value in the first byte means that
867 // initialization is completed. Contents of the remaining
868 // bytes are up to us.
869 constexpr u32 kGuardInit = 0;
870 constexpr u32 kGuardDone = 1;
871 constexpr u32 kGuardRunning = 1 << 16;
872 constexpr u32 kGuardWaiter = 1 << 17;
873 
874 static int guard_acquire(ThreadState *thr, uptr pc, atomic_uint32_t *g,
875                          bool blocking_hooks = true) {
876   if (blocking_hooks)
877     OnPotentiallyBlockingRegionBegin();
878   auto on_exit = at_scope_exit([blocking_hooks] {
879     if (blocking_hooks)
880       OnPotentiallyBlockingRegionEnd();
881   });
882 
883   for (;;) {
884     u32 cmp = atomic_load(g, memory_order_acquire);
885     if (cmp == kGuardInit) {
886       if (atomic_compare_exchange_strong(g, &cmp, kGuardRunning,
887                                          memory_order_relaxed))
888         return 1;
889     } else if (cmp == kGuardDone) {
890       if (!thr->in_ignored_lib)
891         Acquire(thr, pc, (uptr)g);
892       return 0;
893     } else {
894       if ((cmp & kGuardWaiter) ||
895           atomic_compare_exchange_strong(g, &cmp, cmp | kGuardWaiter,
896                                          memory_order_relaxed))
897         FutexWait(g, cmp | kGuardWaiter);
898     }
899   }
900 }
901 
902 static void guard_release(ThreadState *thr, uptr pc, atomic_uint32_t *g,
903                           u32 v) {
904   if (!thr->in_ignored_lib)
905     Release(thr, pc, (uptr)g);
906   u32 old = atomic_exchange(g, v, memory_order_release);
907   if (old & kGuardWaiter)
908     FutexWake(g, 1 << 30);
909 }
910 
911 // __cxa_guard_acquire and friends need to be intercepted in a special way -
912 // regular interceptors will break statically-linked libstdc++. Linux
913 // interceptors are especially defined as weak functions (so that they don't
914 // cause link errors when user defines them as well). So they silently
915 // auto-disable themselves when such symbol is already present in the binary. If
916 // we link libstdc++ statically, it will bring own __cxa_guard_acquire which
917 // will silently replace our interceptor.  That's why on Linux we simply export
918 // these interceptors with INTERFACE_ATTRIBUTE.
919 // On OS X, we don't support statically linking, so we just use a regular
920 // interceptor.
921 #if SANITIZER_APPLE
922 #define STDCXX_INTERCEPTOR TSAN_INTERCEPTOR
923 #else
924 #define STDCXX_INTERCEPTOR(rettype, name, ...) \
925   extern "C" rettype INTERFACE_ATTRIBUTE name(__VA_ARGS__)
926 #endif
927 
928 // Used in thread-safe function static initialization.
929 STDCXX_INTERCEPTOR(int, __cxa_guard_acquire, atomic_uint32_t *g) {
930   SCOPED_INTERCEPTOR_RAW(__cxa_guard_acquire, g);
931   return guard_acquire(thr, pc, g);
932 }
933 
934 STDCXX_INTERCEPTOR(void, __cxa_guard_release, atomic_uint32_t *g) {
935   SCOPED_INTERCEPTOR_RAW(__cxa_guard_release, g);
936   guard_release(thr, pc, g, kGuardDone);
937 }
938 
939 STDCXX_INTERCEPTOR(void, __cxa_guard_abort, atomic_uint32_t *g) {
940   SCOPED_INTERCEPTOR_RAW(__cxa_guard_abort, g);
941   guard_release(thr, pc, g, kGuardInit);
942 }
943 
944 namespace __tsan {
945 void DestroyThreadState() {
946   ThreadState *thr = cur_thread();
947   Processor *proc = thr->proc();
948   ThreadFinish(thr);
949   ProcUnwire(proc, thr);
950   ProcDestroy(proc);
951   DTLS_Destroy();
952   cur_thread_finalize();
953 }
954 
955 void PlatformCleanUpThreadState(ThreadState *thr) {
956   ThreadSignalContext *sctx = (ThreadSignalContext *)atomic_load(
957       &thr->signal_ctx, memory_order_relaxed);
958   if (sctx) {
959     atomic_store(&thr->signal_ctx, 0, memory_order_relaxed);
960     UnmapOrDie(sctx, sizeof(*sctx));
961   }
962 }
963 }  // namespace __tsan
964 
965 #if !SANITIZER_APPLE && !SANITIZER_NETBSD && !SANITIZER_FREEBSD
966 static void thread_finalize(void *v) {
967   uptr iter = (uptr)v;
968   if (iter > 1) {
969     if (pthread_setspecific(interceptor_ctx()->finalize_key,
970         (void*)(iter - 1))) {
971       Printf("ThreadSanitizer: failed to set thread key\n");
972       Die();
973     }
974     return;
975   }
976   DestroyThreadState();
977 }
978 #endif
979 
980 
981 struct ThreadParam {
982   void* (*callback)(void *arg);
983   void *param;
984   Tid tid;
985   Semaphore created;
986   Semaphore started;
987 };
988 
989 extern "C" void *__tsan_thread_start_func(void *arg) {
990   ThreadParam *p = (ThreadParam*)arg;
991   void* (*callback)(void *arg) = p->callback;
992   void *param = p->param;
993   {
994     ThreadState *thr = cur_thread_init();
995     // Thread-local state is not initialized yet.
996     ScopedIgnoreInterceptors ignore;
997 #if !SANITIZER_APPLE && !SANITIZER_NETBSD && !SANITIZER_FREEBSD
998     ThreadIgnoreBegin(thr, 0);
999     if (pthread_setspecific(interceptor_ctx()->finalize_key,
1000                             (void *)GetPthreadDestructorIterations())) {
1001       Printf("ThreadSanitizer: failed to set thread key\n");
1002       Die();
1003     }
1004     ThreadIgnoreEnd(thr);
1005 #endif
1006     p->created.Wait();
1007     Processor *proc = ProcCreate();
1008     ProcWire(proc, thr);
1009     ThreadStart(thr, p->tid, GetTid(), ThreadType::Regular);
1010     p->started.Post();
1011   }
1012   void *res = callback(param);
1013   // Prevent the callback from being tail called,
1014   // it mixes up stack traces.
1015   volatile int foo = 42;
1016   foo++;
1017   return res;
1018 }
1019 
1020 TSAN_INTERCEPTOR(int, pthread_create,
1021     void *th, void *attr, void *(*callback)(void*), void * param) {
1022   SCOPED_INTERCEPTOR_RAW(pthread_create, th, attr, callback, param);
1023 
1024   MaybeSpawnBackgroundThread();
1025 
1026   if (ctx->after_multithreaded_fork) {
1027     if (flags()->die_after_fork) {
1028       Report("ThreadSanitizer: starting new threads after multi-threaded "
1029           "fork is not supported. Dying (set die_after_fork=0 to override)\n");
1030       Die();
1031     } else {
1032       VPrintf(1,
1033               "ThreadSanitizer: starting new threads after multi-threaded "
1034               "fork is not supported (pid %lu). Continuing because of "
1035               "die_after_fork=0, but you are on your own\n",
1036               internal_getpid());
1037     }
1038   }
1039   __sanitizer_pthread_attr_t myattr;
1040   if (attr == 0) {
1041     pthread_attr_init(&myattr);
1042     attr = &myattr;
1043   }
1044   int detached = 0;
1045   REAL(pthread_attr_getdetachstate)(attr, &detached);
1046   AdjustStackSize(attr);
1047 
1048   ThreadParam p;
1049   p.callback = callback;
1050   p.param = param;
1051   p.tid = kMainTid;
1052   int res = -1;
1053   {
1054     // Otherwise we see false positives in pthread stack manipulation.
1055     ScopedIgnoreInterceptors ignore;
1056     ThreadIgnoreBegin(thr, pc);
1057     res = REAL(pthread_create)(th, attr, __tsan_thread_start_func, &p);
1058     ThreadIgnoreEnd(thr);
1059   }
1060   if (res == 0) {
1061     p.tid = ThreadCreate(thr, pc, *(uptr *)th, IsStateDetached(detached));
1062     CHECK_NE(p.tid, kMainTid);
1063     // Synchronization on p.tid serves two purposes:
1064     // 1. ThreadCreate must finish before the new thread starts.
1065     //    Otherwise the new thread can call pthread_detach, but the pthread_t
1066     //    identifier is not yet registered in ThreadRegistry by ThreadCreate.
1067     // 2. ThreadStart must finish before this thread continues.
1068     //    Otherwise, this thread can call pthread_detach and reset thr->sync
1069     //    before the new thread got a chance to acquire from it in ThreadStart.
1070     p.created.Post();
1071     p.started.Wait();
1072   }
1073   if (attr == &myattr)
1074     pthread_attr_destroy(&myattr);
1075   return res;
1076 }
1077 
1078 TSAN_INTERCEPTOR(int, pthread_join, void *th, void **ret) {
1079   SCOPED_INTERCEPTOR_RAW(pthread_join, th, ret);
1080   Tid tid = ThreadConsumeTid(thr, pc, (uptr)th);
1081   ThreadIgnoreBegin(thr, pc);
1082   int res = BLOCK_REAL(pthread_join)(th, ret);
1083   ThreadIgnoreEnd(thr);
1084   if (res == 0) {
1085     ThreadJoin(thr, pc, tid);
1086   }
1087   return res;
1088 }
1089 
1090 DEFINE_REAL_PTHREAD_FUNCTIONS
1091 
1092 TSAN_INTERCEPTOR(int, pthread_detach, void *th) {
1093   SCOPED_INTERCEPTOR_RAW(pthread_detach, th);
1094   Tid tid = ThreadConsumeTid(thr, pc, (uptr)th);
1095   int res = REAL(pthread_detach)(th);
1096   if (res == 0) {
1097     ThreadDetach(thr, pc, tid);
1098   }
1099   return res;
1100 }
1101 
1102 TSAN_INTERCEPTOR(void, pthread_exit, void *retval) {
1103   {
1104     SCOPED_INTERCEPTOR_RAW(pthread_exit, retval);
1105 #if !SANITIZER_APPLE && !SANITIZER_ANDROID
1106     CHECK_EQ(thr, &cur_thread_placeholder);
1107 #endif
1108   }
1109   REAL(pthread_exit)(retval);
1110 }
1111 
1112 #if SANITIZER_LINUX
1113 TSAN_INTERCEPTOR(int, pthread_tryjoin_np, void *th, void **ret) {
1114   SCOPED_INTERCEPTOR_RAW(pthread_tryjoin_np, th, ret);
1115   Tid tid = ThreadConsumeTid(thr, pc, (uptr)th);
1116   ThreadIgnoreBegin(thr, pc);
1117   int res = REAL(pthread_tryjoin_np)(th, ret);
1118   ThreadIgnoreEnd(thr);
1119   if (res == 0)
1120     ThreadJoin(thr, pc, tid);
1121   else
1122     ThreadNotJoined(thr, pc, tid, (uptr)th);
1123   return res;
1124 }
1125 
1126 TSAN_INTERCEPTOR(int, pthread_timedjoin_np, void *th, void **ret,
1127                  const struct timespec *abstime) {
1128   SCOPED_INTERCEPTOR_RAW(pthread_timedjoin_np, th, ret, abstime);
1129   Tid tid = ThreadConsumeTid(thr, pc, (uptr)th);
1130   ThreadIgnoreBegin(thr, pc);
1131   int res = BLOCK_REAL(pthread_timedjoin_np)(th, ret, abstime);
1132   ThreadIgnoreEnd(thr);
1133   if (res == 0)
1134     ThreadJoin(thr, pc, tid);
1135   else
1136     ThreadNotJoined(thr, pc, tid, (uptr)th);
1137   return res;
1138 }
1139 #endif
1140 
1141 // Problem:
1142 // NPTL implementation of pthread_cond has 2 versions (2.2.5 and 2.3.2).
1143 // pthread_cond_t has different size in the different versions.
1144 // If call new REAL functions for old pthread_cond_t, they will corrupt memory
1145 // after pthread_cond_t (old cond is smaller).
1146 // If we call old REAL functions for new pthread_cond_t, we will lose  some
1147 // functionality (e.g. old functions do not support waiting against
1148 // CLOCK_REALTIME).
1149 // Proper handling would require to have 2 versions of interceptors as well.
1150 // But this is messy, in particular requires linker scripts when sanitizer
1151 // runtime is linked into a shared library.
1152 // Instead we assume we don't have dynamic libraries built against old
1153 // pthread (2.2.5 is dated by 2002). And provide legacy_pthread_cond flag
1154 // that allows to work with old libraries (but this mode does not support
1155 // some features, e.g. pthread_condattr_getpshared).
1156 static void *init_cond(void *c, bool force = false) {
1157   // sizeof(pthread_cond_t) >= sizeof(uptr) in both versions.
1158   // So we allocate additional memory on the side large enough to hold
1159   // any pthread_cond_t object. Always call new REAL functions, but pass
1160   // the aux object to them.
1161   // Note: the code assumes that PTHREAD_COND_INITIALIZER initializes
1162   // first word of pthread_cond_t to zero.
1163   // It's all relevant only for linux.
1164   if (!common_flags()->legacy_pthread_cond)
1165     return c;
1166   atomic_uintptr_t *p = (atomic_uintptr_t*)c;
1167   uptr cond = atomic_load(p, memory_order_acquire);
1168   if (!force && cond != 0)
1169     return (void*)cond;
1170   void *newcond = WRAP(malloc)(pthread_cond_t_sz);
1171   internal_memset(newcond, 0, pthread_cond_t_sz);
1172   if (atomic_compare_exchange_strong(p, &cond, (uptr)newcond,
1173       memory_order_acq_rel))
1174     return newcond;
1175   WRAP(free)(newcond);
1176   return (void*)cond;
1177 }
1178 
1179 namespace {
1180 
1181 template <class Fn>
1182 struct CondMutexUnlockCtx {
1183   ScopedInterceptor *si;
1184   ThreadState *thr;
1185   uptr pc;
1186   void *m;
1187   void *c;
1188   const Fn &fn;
1189 
1190   int Cancel() const { return fn(); }
1191   void Unlock() const;
1192 };
1193 
1194 template <class Fn>
1195 void CondMutexUnlockCtx<Fn>::Unlock() const {
1196   // pthread_cond_wait interceptor has enabled async signal delivery
1197   // (see BlockingCall below). Disable async signals since we are running
1198   // tsan code. Also ScopedInterceptor and BlockingCall destructors won't run
1199   // since the thread is cancelled, so we have to manually execute them
1200   // (the thread still can run some user code due to pthread_cleanup_push).
1201   CHECK_EQ(atomic_load(&thr->in_blocking_func, memory_order_relaxed), 1);
1202   atomic_store(&thr->in_blocking_func, 0, memory_order_relaxed);
1203   MutexPostLock(thr, pc, (uptr)m, MutexFlagDoPreLockOnPostLock);
1204   // Undo BlockingCall ctor effects.
1205   thr->ignore_interceptors--;
1206   si->~ScopedInterceptor();
1207 }
1208 }  // namespace
1209 
1210 INTERCEPTOR(int, pthread_cond_init, void *c, void *a) {
1211   void *cond = init_cond(c, true);
1212   SCOPED_TSAN_INTERCEPTOR(pthread_cond_init, cond, a);
1213   MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), true);
1214   return REAL(pthread_cond_init)(cond, a);
1215 }
1216 
1217 template <class Fn>
1218 int cond_wait(ThreadState *thr, uptr pc, ScopedInterceptor *si, const Fn &fn,
1219               void *c, void *m) {
1220   MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), false);
1221   MutexUnlock(thr, pc, (uptr)m);
1222   int res = 0;
1223   // This ensures that we handle mutex lock even in case of pthread_cancel.
1224   // See test/tsan/cond_cancel.cpp.
1225   {
1226     // Enable signal delivery while the thread is blocked.
1227     BlockingCall bc(thr);
1228     CondMutexUnlockCtx<Fn> arg = {si, thr, pc, m, c, fn};
1229     res = call_pthread_cancel_with_cleanup(
1230         [](void *arg) -> int {
1231           return ((const CondMutexUnlockCtx<Fn> *)arg)->Cancel();
1232         },
1233         [](void *arg) { ((const CondMutexUnlockCtx<Fn> *)arg)->Unlock(); },
1234         &arg);
1235   }
1236   if (res == errno_EOWNERDEAD) MutexRepair(thr, pc, (uptr)m);
1237   MutexPostLock(thr, pc, (uptr)m, MutexFlagDoPreLockOnPostLock);
1238   return res;
1239 }
1240 
1241 INTERCEPTOR(int, pthread_cond_wait, void *c, void *m) {
1242   void *cond = init_cond(c);
1243   SCOPED_TSAN_INTERCEPTOR(pthread_cond_wait, cond, m);
1244   return cond_wait(
1245       thr, pc, &si, [=]() { return REAL(pthread_cond_wait)(cond, m); }, cond,
1246       m);
1247 }
1248 
1249 INTERCEPTOR(int, pthread_cond_timedwait, void *c, void *m, void *abstime) {
1250   void *cond = init_cond(c);
1251   SCOPED_TSAN_INTERCEPTOR(pthread_cond_timedwait, cond, m, abstime);
1252   return cond_wait(
1253       thr, pc, &si,
1254       [=]() { return REAL(pthread_cond_timedwait)(cond, m, abstime); }, cond,
1255       m);
1256 }
1257 
1258 #if SANITIZER_LINUX
1259 INTERCEPTOR(int, pthread_cond_clockwait, void *c, void *m,
1260             __sanitizer_clockid_t clock, void *abstime) {
1261   void *cond = init_cond(c);
1262   SCOPED_TSAN_INTERCEPTOR(pthread_cond_clockwait, cond, m, clock, abstime);
1263   return cond_wait(
1264       thr, pc, &si,
1265       [=]() { return REAL(pthread_cond_clockwait)(cond, m, clock, abstime); },
1266       cond, m);
1267 }
1268 #define TSAN_MAYBE_PTHREAD_COND_CLOCKWAIT TSAN_INTERCEPT(pthread_cond_clockwait)
1269 #else
1270 #define TSAN_MAYBE_PTHREAD_COND_CLOCKWAIT
1271 #endif
1272 
1273 #if SANITIZER_APPLE
1274 INTERCEPTOR(int, pthread_cond_timedwait_relative_np, void *c, void *m,
1275             void *reltime) {
1276   void *cond = init_cond(c);
1277   SCOPED_TSAN_INTERCEPTOR(pthread_cond_timedwait_relative_np, cond, m, reltime);
1278   return cond_wait(
1279       thr, pc, &si,
1280       [=]() {
1281         return REAL(pthread_cond_timedwait_relative_np)(cond, m, reltime);
1282       },
1283       cond, m);
1284 }
1285 #endif
1286 
1287 INTERCEPTOR(int, pthread_cond_signal, void *c) {
1288   void *cond = init_cond(c);
1289   SCOPED_TSAN_INTERCEPTOR(pthread_cond_signal, cond);
1290   MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), false);
1291   return REAL(pthread_cond_signal)(cond);
1292 }
1293 
1294 INTERCEPTOR(int, pthread_cond_broadcast, void *c) {
1295   void *cond = init_cond(c);
1296   SCOPED_TSAN_INTERCEPTOR(pthread_cond_broadcast, cond);
1297   MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), false);
1298   return REAL(pthread_cond_broadcast)(cond);
1299 }
1300 
1301 INTERCEPTOR(int, pthread_cond_destroy, void *c) {
1302   void *cond = init_cond(c);
1303   SCOPED_TSAN_INTERCEPTOR(pthread_cond_destroy, cond);
1304   MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), true);
1305   int res = REAL(pthread_cond_destroy)(cond);
1306   if (common_flags()->legacy_pthread_cond) {
1307     // Free our aux cond and zero the pointer to not leave dangling pointers.
1308     WRAP(free)(cond);
1309     atomic_store((atomic_uintptr_t*)c, 0, memory_order_relaxed);
1310   }
1311   return res;
1312 }
1313 
1314 TSAN_INTERCEPTOR(int, pthread_mutex_init, void *m, void *a) {
1315   SCOPED_TSAN_INTERCEPTOR(pthread_mutex_init, m, a);
1316   int res = REAL(pthread_mutex_init)(m, a);
1317   if (res == 0) {
1318     u32 flagz = 0;
1319     if (a) {
1320       int type = 0;
1321       if (REAL(pthread_mutexattr_gettype)(a, &type) == 0)
1322         if (type == PTHREAD_MUTEX_RECURSIVE ||
1323             type == PTHREAD_MUTEX_RECURSIVE_NP)
1324           flagz |= MutexFlagWriteReentrant;
1325     }
1326     MutexCreate(thr, pc, (uptr)m, flagz);
1327   }
1328   return res;
1329 }
1330 
1331 TSAN_INTERCEPTOR(int, pthread_mutex_destroy, void *m) {
1332   SCOPED_TSAN_INTERCEPTOR(pthread_mutex_destroy, m);
1333   int res = REAL(pthread_mutex_destroy)(m);
1334   if (res == 0 || res == errno_EBUSY) {
1335     MutexDestroy(thr, pc, (uptr)m);
1336   }
1337   return res;
1338 }
1339 
1340 TSAN_INTERCEPTOR(int, pthread_mutex_lock, void *m) {
1341   SCOPED_TSAN_INTERCEPTOR(pthread_mutex_lock, m);
1342   MutexPreLock(thr, pc, (uptr)m);
1343   int res = REAL(pthread_mutex_lock)(m);
1344   if (res == errno_EOWNERDEAD)
1345     MutexRepair(thr, pc, (uptr)m);
1346   if (res == 0 || res == errno_EOWNERDEAD)
1347     MutexPostLock(thr, pc, (uptr)m);
1348   if (res == errno_EINVAL)
1349     MutexInvalidAccess(thr, pc, (uptr)m);
1350   return res;
1351 }
1352 
1353 TSAN_INTERCEPTOR(int, pthread_mutex_trylock, void *m) {
1354   SCOPED_TSAN_INTERCEPTOR(pthread_mutex_trylock, m);
1355   int res = REAL(pthread_mutex_trylock)(m);
1356   if (res == errno_EOWNERDEAD)
1357     MutexRepair(thr, pc, (uptr)m);
1358   if (res == 0 || res == errno_EOWNERDEAD)
1359     MutexPostLock(thr, pc, (uptr)m, MutexFlagTryLock);
1360   return res;
1361 }
1362 
1363 #if !SANITIZER_APPLE
1364 TSAN_INTERCEPTOR(int, pthread_mutex_timedlock, void *m, void *abstime) {
1365   SCOPED_TSAN_INTERCEPTOR(pthread_mutex_timedlock, m, abstime);
1366   int res = REAL(pthread_mutex_timedlock)(m, abstime);
1367   if (res == 0) {
1368     MutexPostLock(thr, pc, (uptr)m, MutexFlagTryLock);
1369   }
1370   return res;
1371 }
1372 #endif
1373 
1374 TSAN_INTERCEPTOR(int, pthread_mutex_unlock, void *m) {
1375   SCOPED_TSAN_INTERCEPTOR(pthread_mutex_unlock, m);
1376   MutexUnlock(thr, pc, (uptr)m);
1377   int res = REAL(pthread_mutex_unlock)(m);
1378   if (res == errno_EINVAL)
1379     MutexInvalidAccess(thr, pc, (uptr)m);
1380   return res;
1381 }
1382 
1383 #if SANITIZER_LINUX
1384 TSAN_INTERCEPTOR(int, pthread_mutex_clocklock, void *m,
1385                  __sanitizer_clockid_t clock, void *abstime) {
1386   SCOPED_TSAN_INTERCEPTOR(pthread_mutex_clocklock, m, clock, abstime);
1387   MutexPreLock(thr, pc, (uptr)m);
1388   int res = REAL(pthread_mutex_clocklock)(m, clock, abstime);
1389   if (res == errno_EOWNERDEAD)
1390     MutexRepair(thr, pc, (uptr)m);
1391   if (res == 0 || res == errno_EOWNERDEAD)
1392     MutexPostLock(thr, pc, (uptr)m);
1393   if (res == errno_EINVAL)
1394     MutexInvalidAccess(thr, pc, (uptr)m);
1395   return res;
1396 }
1397 #endif
1398 
1399 #if SANITIZER_GLIBC
1400 #  if !__GLIBC_PREREQ(2, 34)
1401 // glibc 2.34 applies a non-default version for the two functions. They are no
1402 // longer expected to be intercepted by programs.
1403 TSAN_INTERCEPTOR(int, __pthread_mutex_lock, void *m) {
1404   SCOPED_TSAN_INTERCEPTOR(__pthread_mutex_lock, m);
1405   MutexPreLock(thr, pc, (uptr)m);
1406   int res = REAL(__pthread_mutex_lock)(m);
1407   if (res == errno_EOWNERDEAD)
1408     MutexRepair(thr, pc, (uptr)m);
1409   if (res == 0 || res == errno_EOWNERDEAD)
1410     MutexPostLock(thr, pc, (uptr)m);
1411   if (res == errno_EINVAL)
1412     MutexInvalidAccess(thr, pc, (uptr)m);
1413   return res;
1414 }
1415 
1416 TSAN_INTERCEPTOR(int, __pthread_mutex_unlock, void *m) {
1417   SCOPED_TSAN_INTERCEPTOR(__pthread_mutex_unlock, m);
1418   MutexUnlock(thr, pc, (uptr)m);
1419   int res = REAL(__pthread_mutex_unlock)(m);
1420   if (res == errno_EINVAL)
1421     MutexInvalidAccess(thr, pc, (uptr)m);
1422   return res;
1423 }
1424 #  endif
1425 #endif
1426 
1427 #if !SANITIZER_APPLE
1428 TSAN_INTERCEPTOR(int, pthread_spin_init, void *m, int pshared) {
1429   SCOPED_TSAN_INTERCEPTOR(pthread_spin_init, m, pshared);
1430   int res = REAL(pthread_spin_init)(m, pshared);
1431   if (res == 0) {
1432     MutexCreate(thr, pc, (uptr)m);
1433   }
1434   return res;
1435 }
1436 
1437 TSAN_INTERCEPTOR(int, pthread_spin_destroy, void *m) {
1438   SCOPED_TSAN_INTERCEPTOR(pthread_spin_destroy, m);
1439   int res = REAL(pthread_spin_destroy)(m);
1440   if (res == 0) {
1441     MutexDestroy(thr, pc, (uptr)m);
1442   }
1443   return res;
1444 }
1445 
1446 TSAN_INTERCEPTOR(int, pthread_spin_lock, void *m) {
1447   SCOPED_TSAN_INTERCEPTOR(pthread_spin_lock, m);
1448   MutexPreLock(thr, pc, (uptr)m);
1449   int res = REAL(pthread_spin_lock)(m);
1450   if (res == 0) {
1451     MutexPostLock(thr, pc, (uptr)m);
1452   }
1453   return res;
1454 }
1455 
1456 TSAN_INTERCEPTOR(int, pthread_spin_trylock, void *m) {
1457   SCOPED_TSAN_INTERCEPTOR(pthread_spin_trylock, m);
1458   int res = REAL(pthread_spin_trylock)(m);
1459   if (res == 0) {
1460     MutexPostLock(thr, pc, (uptr)m, MutexFlagTryLock);
1461   }
1462   return res;
1463 }
1464 
1465 TSAN_INTERCEPTOR(int, pthread_spin_unlock, void *m) {
1466   SCOPED_TSAN_INTERCEPTOR(pthread_spin_unlock, m);
1467   MutexUnlock(thr, pc, (uptr)m);
1468   int res = REAL(pthread_spin_unlock)(m);
1469   return res;
1470 }
1471 #endif
1472 
1473 TSAN_INTERCEPTOR(int, pthread_rwlock_init, void *m, void *a) {
1474   SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_init, m, a);
1475   int res = REAL(pthread_rwlock_init)(m, a);
1476   if (res == 0) {
1477     MutexCreate(thr, pc, (uptr)m);
1478   }
1479   return res;
1480 }
1481 
1482 TSAN_INTERCEPTOR(int, pthread_rwlock_destroy, void *m) {
1483   SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_destroy, m);
1484   int res = REAL(pthread_rwlock_destroy)(m);
1485   if (res == 0) {
1486     MutexDestroy(thr, pc, (uptr)m);
1487   }
1488   return res;
1489 }
1490 
1491 TSAN_INTERCEPTOR(int, pthread_rwlock_rdlock, void *m) {
1492   SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_rdlock, m);
1493   MutexPreReadLock(thr, pc, (uptr)m);
1494   int res = REAL(pthread_rwlock_rdlock)(m);
1495   if (res == 0) {
1496     MutexPostReadLock(thr, pc, (uptr)m);
1497   }
1498   return res;
1499 }
1500 
1501 TSAN_INTERCEPTOR(int, pthread_rwlock_tryrdlock, void *m) {
1502   SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_tryrdlock, m);
1503   int res = REAL(pthread_rwlock_tryrdlock)(m);
1504   if (res == 0) {
1505     MutexPostReadLock(thr, pc, (uptr)m, MutexFlagTryLock);
1506   }
1507   return res;
1508 }
1509 
1510 #if !SANITIZER_APPLE
1511 TSAN_INTERCEPTOR(int, pthread_rwlock_timedrdlock, void *m, void *abstime) {
1512   SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_timedrdlock, m, abstime);
1513   int res = REAL(pthread_rwlock_timedrdlock)(m, abstime);
1514   if (res == 0) {
1515     MutexPostReadLock(thr, pc, (uptr)m);
1516   }
1517   return res;
1518 }
1519 #endif
1520 
1521 TSAN_INTERCEPTOR(int, pthread_rwlock_wrlock, void *m) {
1522   SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_wrlock, m);
1523   MutexPreLock(thr, pc, (uptr)m);
1524   int res = REAL(pthread_rwlock_wrlock)(m);
1525   if (res == 0) {
1526     MutexPostLock(thr, pc, (uptr)m);
1527   }
1528   return res;
1529 }
1530 
1531 TSAN_INTERCEPTOR(int, pthread_rwlock_trywrlock, void *m) {
1532   SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_trywrlock, m);
1533   int res = REAL(pthread_rwlock_trywrlock)(m);
1534   if (res == 0) {
1535     MutexPostLock(thr, pc, (uptr)m, MutexFlagTryLock);
1536   }
1537   return res;
1538 }
1539 
1540 #if !SANITIZER_APPLE
1541 TSAN_INTERCEPTOR(int, pthread_rwlock_timedwrlock, void *m, void *abstime) {
1542   SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_timedwrlock, m, abstime);
1543   int res = REAL(pthread_rwlock_timedwrlock)(m, abstime);
1544   if (res == 0) {
1545     MutexPostLock(thr, pc, (uptr)m, MutexFlagTryLock);
1546   }
1547   return res;
1548 }
1549 #endif
1550 
1551 TSAN_INTERCEPTOR(int, pthread_rwlock_unlock, void *m) {
1552   SCOPED_TSAN_INTERCEPTOR(pthread_rwlock_unlock, m);
1553   MutexReadOrWriteUnlock(thr, pc, (uptr)m);
1554   int res = REAL(pthread_rwlock_unlock)(m);
1555   return res;
1556 }
1557 
1558 #if !SANITIZER_APPLE
1559 TSAN_INTERCEPTOR(int, pthread_barrier_init, void *b, void *a, unsigned count) {
1560   SCOPED_TSAN_INTERCEPTOR(pthread_barrier_init, b, a, count);
1561   MemoryAccess(thr, pc, (uptr)b, 1, kAccessWrite);
1562   int res = REAL(pthread_barrier_init)(b, a, count);
1563   return res;
1564 }
1565 
1566 TSAN_INTERCEPTOR(int, pthread_barrier_destroy, void *b) {
1567   SCOPED_TSAN_INTERCEPTOR(pthread_barrier_destroy, b);
1568   MemoryAccess(thr, pc, (uptr)b, 1, kAccessWrite);
1569   int res = REAL(pthread_barrier_destroy)(b);
1570   return res;
1571 }
1572 
1573 TSAN_INTERCEPTOR(int, pthread_barrier_wait, void *b) {
1574   SCOPED_TSAN_INTERCEPTOR(pthread_barrier_wait, b);
1575   Release(thr, pc, (uptr)b);
1576   MemoryAccess(thr, pc, (uptr)b, 1, kAccessRead);
1577   int res = REAL(pthread_barrier_wait)(b);
1578   MemoryAccess(thr, pc, (uptr)b, 1, kAccessRead);
1579   if (res == 0 || res == PTHREAD_BARRIER_SERIAL_THREAD) {
1580     Acquire(thr, pc, (uptr)b);
1581   }
1582   return res;
1583 }
1584 #endif
1585 
1586 TSAN_INTERCEPTOR(int, pthread_once, void *o, void (*f)()) {
1587   SCOPED_INTERCEPTOR_RAW(pthread_once, o, f);
1588   if (o == 0 || f == 0)
1589     return errno_EINVAL;
1590   atomic_uint32_t *a;
1591 
1592   if (SANITIZER_APPLE)
1593     a = static_cast<atomic_uint32_t*>((void *)((char *)o + sizeof(long_t)));
1594   else if (SANITIZER_NETBSD)
1595     a = static_cast<atomic_uint32_t*>
1596           ((void *)((char *)o + __sanitizer::pthread_mutex_t_sz));
1597   else
1598     a = static_cast<atomic_uint32_t*>(o);
1599 
1600   // Mac OS X appears to use pthread_once() where calling BlockingRegion hooks
1601   // result in crashes due to too little stack space.
1602   if (guard_acquire(thr, pc, a, !SANITIZER_APPLE)) {
1603     (*f)();
1604     guard_release(thr, pc, a, kGuardDone);
1605   }
1606   return 0;
1607 }
1608 
1609 #if SANITIZER_GLIBC
1610 TSAN_INTERCEPTOR(int, __fxstat, int version, int fd, void *buf) {
1611   SCOPED_TSAN_INTERCEPTOR(__fxstat, version, fd, buf);
1612   if (fd > 0)
1613     FdAccess(thr, pc, fd);
1614   return REAL(__fxstat)(version, fd, buf);
1615 }
1616 #define TSAN_MAYBE_INTERCEPT___FXSTAT TSAN_INTERCEPT(__fxstat)
1617 #else
1618 #define TSAN_MAYBE_INTERCEPT___FXSTAT
1619 #endif
1620 
1621 TSAN_INTERCEPTOR(int, fstat, int fd, void *buf) {
1622 #if SANITIZER_GLIBC
1623   SCOPED_TSAN_INTERCEPTOR(__fxstat, 0, fd, buf);
1624   if (fd > 0)
1625     FdAccess(thr, pc, fd);
1626   return REAL(__fxstat)(0, fd, buf);
1627 #else
1628   SCOPED_TSAN_INTERCEPTOR(fstat, fd, buf);
1629   if (fd > 0)
1630     FdAccess(thr, pc, fd);
1631   return REAL(fstat)(fd, buf);
1632 #endif
1633 }
1634 
1635 #if SANITIZER_GLIBC
1636 TSAN_INTERCEPTOR(int, __fxstat64, int version, int fd, void *buf) {
1637   SCOPED_TSAN_INTERCEPTOR(__fxstat64, version, fd, buf);
1638   if (fd > 0)
1639     FdAccess(thr, pc, fd);
1640   return REAL(__fxstat64)(version, fd, buf);
1641 }
1642 #define TSAN_MAYBE_INTERCEPT___FXSTAT64 TSAN_INTERCEPT(__fxstat64)
1643 #else
1644 #define TSAN_MAYBE_INTERCEPT___FXSTAT64
1645 #endif
1646 
1647 #if SANITIZER_GLIBC
1648 TSAN_INTERCEPTOR(int, fstat64, int fd, void *buf) {
1649   SCOPED_TSAN_INTERCEPTOR(__fxstat64, 0, fd, buf);
1650   if (fd > 0)
1651     FdAccess(thr, pc, fd);
1652   return REAL(__fxstat64)(0, fd, buf);
1653 }
1654 #define TSAN_MAYBE_INTERCEPT_FSTAT64 TSAN_INTERCEPT(fstat64)
1655 #else
1656 #define TSAN_MAYBE_INTERCEPT_FSTAT64
1657 #endif
1658 
1659 TSAN_INTERCEPTOR(int, open, const char *name, int oflag, ...) {
1660   va_list ap;
1661   va_start(ap, oflag);
1662   mode_t mode = va_arg(ap, int);
1663   va_end(ap);
1664   SCOPED_TSAN_INTERCEPTOR(open, name, oflag, mode);
1665   READ_STRING(thr, pc, name, 0);
1666   int fd = REAL(open)(name, oflag, mode);
1667   if (fd >= 0)
1668     FdFileCreate(thr, pc, fd);
1669   return fd;
1670 }
1671 
1672 #if SANITIZER_LINUX
1673 TSAN_INTERCEPTOR(int, open64, const char *name, int oflag, ...) {
1674   va_list ap;
1675   va_start(ap, oflag);
1676   mode_t mode = va_arg(ap, int);
1677   va_end(ap);
1678   SCOPED_TSAN_INTERCEPTOR(open64, name, oflag, mode);
1679   READ_STRING(thr, pc, name, 0);
1680   int fd = REAL(open64)(name, oflag, mode);
1681   if (fd >= 0)
1682     FdFileCreate(thr, pc, fd);
1683   return fd;
1684 }
1685 #define TSAN_MAYBE_INTERCEPT_OPEN64 TSAN_INTERCEPT(open64)
1686 #else
1687 #define TSAN_MAYBE_INTERCEPT_OPEN64
1688 #endif
1689 
1690 TSAN_INTERCEPTOR(int, creat, const char *name, int mode) {
1691   SCOPED_TSAN_INTERCEPTOR(creat, name, mode);
1692   READ_STRING(thr, pc, name, 0);
1693   int fd = REAL(creat)(name, mode);
1694   if (fd >= 0)
1695     FdFileCreate(thr, pc, fd);
1696   return fd;
1697 }
1698 
1699 #if SANITIZER_LINUX
1700 TSAN_INTERCEPTOR(int, creat64, const char *name, int mode) {
1701   SCOPED_TSAN_INTERCEPTOR(creat64, name, mode);
1702   READ_STRING(thr, pc, name, 0);
1703   int fd = REAL(creat64)(name, mode);
1704   if (fd >= 0)
1705     FdFileCreate(thr, pc, fd);
1706   return fd;
1707 }
1708 #define TSAN_MAYBE_INTERCEPT_CREAT64 TSAN_INTERCEPT(creat64)
1709 #else
1710 #define TSAN_MAYBE_INTERCEPT_CREAT64
1711 #endif
1712 
1713 TSAN_INTERCEPTOR(int, dup, int oldfd) {
1714   SCOPED_TSAN_INTERCEPTOR(dup, oldfd);
1715   int newfd = REAL(dup)(oldfd);
1716   if (oldfd >= 0 && newfd >= 0 && newfd != oldfd)
1717     FdDup(thr, pc, oldfd, newfd, true);
1718   return newfd;
1719 }
1720 
1721 TSAN_INTERCEPTOR(int, dup2, int oldfd, int newfd) {
1722   SCOPED_TSAN_INTERCEPTOR(dup2, oldfd, newfd);
1723   int newfd2 = REAL(dup2)(oldfd, newfd);
1724   if (oldfd >= 0 && newfd2 >= 0 && newfd2 != oldfd)
1725     FdDup(thr, pc, oldfd, newfd2, false);
1726   return newfd2;
1727 }
1728 
1729 #if !SANITIZER_APPLE
1730 TSAN_INTERCEPTOR(int, dup3, int oldfd, int newfd, int flags) {
1731   SCOPED_TSAN_INTERCEPTOR(dup3, oldfd, newfd, flags);
1732   int newfd2 = REAL(dup3)(oldfd, newfd, flags);
1733   if (oldfd >= 0 && newfd2 >= 0 && newfd2 != oldfd)
1734     FdDup(thr, pc, oldfd, newfd2, false);
1735   return newfd2;
1736 }
1737 #endif
1738 
1739 #if SANITIZER_LINUX
1740 TSAN_INTERCEPTOR(int, eventfd, unsigned initval, int flags) {
1741   SCOPED_TSAN_INTERCEPTOR(eventfd, initval, flags);
1742   int fd = REAL(eventfd)(initval, flags);
1743   if (fd >= 0)
1744     FdEventCreate(thr, pc, fd);
1745   return fd;
1746 }
1747 #define TSAN_MAYBE_INTERCEPT_EVENTFD TSAN_INTERCEPT(eventfd)
1748 #else
1749 #define TSAN_MAYBE_INTERCEPT_EVENTFD
1750 #endif
1751 
1752 #if SANITIZER_LINUX
1753 TSAN_INTERCEPTOR(int, signalfd, int fd, void *mask, int flags) {
1754   SCOPED_INTERCEPTOR_RAW(signalfd, fd, mask, flags);
1755   FdClose(thr, pc, fd);
1756   fd = REAL(signalfd)(fd, mask, flags);
1757   if (!MustIgnoreInterceptor(thr))
1758     FdSignalCreate(thr, pc, fd);
1759   return fd;
1760 }
1761 #define TSAN_MAYBE_INTERCEPT_SIGNALFD TSAN_INTERCEPT(signalfd)
1762 #else
1763 #define TSAN_MAYBE_INTERCEPT_SIGNALFD
1764 #endif
1765 
1766 #if SANITIZER_LINUX
1767 TSAN_INTERCEPTOR(int, inotify_init, int fake) {
1768   SCOPED_TSAN_INTERCEPTOR(inotify_init, fake);
1769   int fd = REAL(inotify_init)(fake);
1770   if (fd >= 0)
1771     FdInotifyCreate(thr, pc, fd);
1772   return fd;
1773 }
1774 #define TSAN_MAYBE_INTERCEPT_INOTIFY_INIT TSAN_INTERCEPT(inotify_init)
1775 #else
1776 #define TSAN_MAYBE_INTERCEPT_INOTIFY_INIT
1777 #endif
1778 
1779 #if SANITIZER_LINUX
1780 TSAN_INTERCEPTOR(int, inotify_init1, int flags) {
1781   SCOPED_TSAN_INTERCEPTOR(inotify_init1, flags);
1782   int fd = REAL(inotify_init1)(flags);
1783   if (fd >= 0)
1784     FdInotifyCreate(thr, pc, fd);
1785   return fd;
1786 }
1787 #define TSAN_MAYBE_INTERCEPT_INOTIFY_INIT1 TSAN_INTERCEPT(inotify_init1)
1788 #else
1789 #define TSAN_MAYBE_INTERCEPT_INOTIFY_INIT1
1790 #endif
1791 
1792 TSAN_INTERCEPTOR(int, socket, int domain, int type, int protocol) {
1793   SCOPED_TSAN_INTERCEPTOR(socket, domain, type, protocol);
1794   int fd = REAL(socket)(domain, type, protocol);
1795   if (fd >= 0)
1796     FdSocketCreate(thr, pc, fd);
1797   return fd;
1798 }
1799 
1800 TSAN_INTERCEPTOR(int, socketpair, int domain, int type, int protocol, int *fd) {
1801   SCOPED_TSAN_INTERCEPTOR(socketpair, domain, type, protocol, fd);
1802   int res = REAL(socketpair)(domain, type, protocol, fd);
1803   if (res == 0 && fd[0] >= 0 && fd[1] >= 0)
1804     FdPipeCreate(thr, pc, fd[0], fd[1]);
1805   return res;
1806 }
1807 
1808 TSAN_INTERCEPTOR(int, connect, int fd, void *addr, unsigned addrlen) {
1809   SCOPED_TSAN_INTERCEPTOR(connect, fd, addr, addrlen);
1810   FdSocketConnecting(thr, pc, fd);
1811   int res = REAL(connect)(fd, addr, addrlen);
1812   if (res == 0 && fd >= 0)
1813     FdSocketConnect(thr, pc, fd);
1814   return res;
1815 }
1816 
1817 TSAN_INTERCEPTOR(int, bind, int fd, void *addr, unsigned addrlen) {
1818   SCOPED_TSAN_INTERCEPTOR(bind, fd, addr, addrlen);
1819   int res = REAL(bind)(fd, addr, addrlen);
1820   if (fd > 0 && res == 0)
1821     FdAccess(thr, pc, fd);
1822   return res;
1823 }
1824 
1825 TSAN_INTERCEPTOR(int, listen, int fd, int backlog) {
1826   SCOPED_TSAN_INTERCEPTOR(listen, fd, backlog);
1827   int res = REAL(listen)(fd, backlog);
1828   if (fd > 0 && res == 0)
1829     FdAccess(thr, pc, fd);
1830   return res;
1831 }
1832 
1833 TSAN_INTERCEPTOR(int, close, int fd) {
1834   SCOPED_INTERCEPTOR_RAW(close, fd);
1835   if (!in_symbolizer())
1836     FdClose(thr, pc, fd);
1837   return REAL(close)(fd);
1838 }
1839 
1840 #if SANITIZER_LINUX
1841 TSAN_INTERCEPTOR(int, __close, int fd) {
1842   SCOPED_INTERCEPTOR_RAW(__close, fd);
1843   FdClose(thr, pc, fd);
1844   return REAL(__close)(fd);
1845 }
1846 #define TSAN_MAYBE_INTERCEPT___CLOSE TSAN_INTERCEPT(__close)
1847 #else
1848 #define TSAN_MAYBE_INTERCEPT___CLOSE
1849 #endif
1850 
1851 // glibc guts
1852 #if SANITIZER_LINUX && !SANITIZER_ANDROID
1853 TSAN_INTERCEPTOR(void, __res_iclose, void *state, bool free_addr) {
1854   SCOPED_INTERCEPTOR_RAW(__res_iclose, state, free_addr);
1855   int fds[64];
1856   int cnt = ExtractResolvFDs(state, fds, ARRAY_SIZE(fds));
1857   for (int i = 0; i < cnt; i++) FdClose(thr, pc, fds[i]);
1858   REAL(__res_iclose)(state, free_addr);
1859 }
1860 #define TSAN_MAYBE_INTERCEPT___RES_ICLOSE TSAN_INTERCEPT(__res_iclose)
1861 #else
1862 #define TSAN_MAYBE_INTERCEPT___RES_ICLOSE
1863 #endif
1864 
1865 TSAN_INTERCEPTOR(int, pipe, int *pipefd) {
1866   SCOPED_TSAN_INTERCEPTOR(pipe, pipefd);
1867   int res = REAL(pipe)(pipefd);
1868   if (res == 0 && pipefd[0] >= 0 && pipefd[1] >= 0)
1869     FdPipeCreate(thr, pc, pipefd[0], pipefd[1]);
1870   return res;
1871 }
1872 
1873 #if !SANITIZER_APPLE
1874 TSAN_INTERCEPTOR(int, pipe2, int *pipefd, int flags) {
1875   SCOPED_TSAN_INTERCEPTOR(pipe2, pipefd, flags);
1876   int res = REAL(pipe2)(pipefd, flags);
1877   if (res == 0 && pipefd[0] >= 0 && pipefd[1] >= 0)
1878     FdPipeCreate(thr, pc, pipefd[0], pipefd[1]);
1879   return res;
1880 }
1881 #endif
1882 
1883 TSAN_INTERCEPTOR(int, unlink, char *path) {
1884   SCOPED_TSAN_INTERCEPTOR(unlink, path);
1885   Release(thr, pc, File2addr(path));
1886   int res = REAL(unlink)(path);
1887   return res;
1888 }
1889 
1890 TSAN_INTERCEPTOR(void*, tmpfile, int fake) {
1891   SCOPED_TSAN_INTERCEPTOR(tmpfile, fake);
1892   void *res = REAL(tmpfile)(fake);
1893   if (res) {
1894     int fd = fileno_unlocked(res);
1895     if (fd >= 0)
1896       FdFileCreate(thr, pc, fd);
1897   }
1898   return res;
1899 }
1900 
1901 #if SANITIZER_LINUX
1902 TSAN_INTERCEPTOR(void*, tmpfile64, int fake) {
1903   SCOPED_TSAN_INTERCEPTOR(tmpfile64, fake);
1904   void *res = REAL(tmpfile64)(fake);
1905   if (res) {
1906     int fd = fileno_unlocked(res);
1907     if (fd >= 0)
1908       FdFileCreate(thr, pc, fd);
1909   }
1910   return res;
1911 }
1912 #define TSAN_MAYBE_INTERCEPT_TMPFILE64 TSAN_INTERCEPT(tmpfile64)
1913 #else
1914 #define TSAN_MAYBE_INTERCEPT_TMPFILE64
1915 #endif
1916 
1917 static void FlushStreams() {
1918   // Flushing all the streams here may freeze the process if a child thread is
1919   // performing file stream operations at the same time.
1920   REAL(fflush)(stdout);
1921   REAL(fflush)(stderr);
1922 }
1923 
1924 TSAN_INTERCEPTOR(void, abort, int fake) {
1925   SCOPED_TSAN_INTERCEPTOR(abort, fake);
1926   FlushStreams();
1927   REAL(abort)(fake);
1928 }
1929 
1930 TSAN_INTERCEPTOR(int, rmdir, char *path) {
1931   SCOPED_TSAN_INTERCEPTOR(rmdir, path);
1932   Release(thr, pc, Dir2addr(path));
1933   int res = REAL(rmdir)(path);
1934   return res;
1935 }
1936 
1937 TSAN_INTERCEPTOR(int, closedir, void *dirp) {
1938   SCOPED_INTERCEPTOR_RAW(closedir, dirp);
1939   if (dirp) {
1940     int fd = dirfd(dirp);
1941     FdClose(thr, pc, fd);
1942   }
1943   return REAL(closedir)(dirp);
1944 }
1945 
1946 #if SANITIZER_LINUX
1947 TSAN_INTERCEPTOR(int, epoll_create, int size) {
1948   SCOPED_TSAN_INTERCEPTOR(epoll_create, size);
1949   int fd = REAL(epoll_create)(size);
1950   if (fd >= 0)
1951     FdPollCreate(thr, pc, fd);
1952   return fd;
1953 }
1954 
1955 TSAN_INTERCEPTOR(int, epoll_create1, int flags) {
1956   SCOPED_TSAN_INTERCEPTOR(epoll_create1, flags);
1957   int fd = REAL(epoll_create1)(flags);
1958   if (fd >= 0)
1959     FdPollCreate(thr, pc, fd);
1960   return fd;
1961 }
1962 
1963 TSAN_INTERCEPTOR(int, epoll_ctl, int epfd, int op, int fd, void *ev) {
1964   SCOPED_TSAN_INTERCEPTOR(epoll_ctl, epfd, op, fd, ev);
1965   if (epfd >= 0)
1966     FdAccess(thr, pc, epfd);
1967   if (epfd >= 0 && fd >= 0)
1968     FdAccess(thr, pc, fd);
1969   if (op == EPOLL_CTL_ADD && epfd >= 0) {
1970     FdPollAdd(thr, pc, epfd, fd);
1971     FdRelease(thr, pc, epfd);
1972   }
1973   int res = REAL(epoll_ctl)(epfd, op, fd, ev);
1974   return res;
1975 }
1976 
1977 TSAN_INTERCEPTOR(int, epoll_wait, int epfd, void *ev, int cnt, int timeout) {
1978   SCOPED_TSAN_INTERCEPTOR(epoll_wait, epfd, ev, cnt, timeout);
1979   if (epfd >= 0)
1980     FdAccess(thr, pc, epfd);
1981   int res = BLOCK_REAL(epoll_wait)(epfd, ev, cnt, timeout);
1982   if (res > 0 && epfd >= 0)
1983     FdAcquire(thr, pc, epfd);
1984   return res;
1985 }
1986 
1987 TSAN_INTERCEPTOR(int, epoll_pwait, int epfd, void *ev, int cnt, int timeout,
1988                  void *sigmask) {
1989   SCOPED_TSAN_INTERCEPTOR(epoll_pwait, epfd, ev, cnt, timeout, sigmask);
1990   if (epfd >= 0)
1991     FdAccess(thr, pc, epfd);
1992   int res = BLOCK_REAL(epoll_pwait)(epfd, ev, cnt, timeout, sigmask);
1993   if (res > 0 && epfd >= 0)
1994     FdAcquire(thr, pc, epfd);
1995   return res;
1996 }
1997 
1998 TSAN_INTERCEPTOR(int, epoll_pwait2, int epfd, void *ev, int cnt, void *timeout,
1999                  void *sigmask) {
2000   SCOPED_INTERCEPTOR_RAW(epoll_pwait2, epfd, ev, cnt, timeout, sigmask);
2001   // This function is new and may not be present in libc and/or kernel.
2002   // Since we effectively add it to libc (as will be probed by the program
2003   // using dlsym or a weak function pointer) we need to handle the case
2004   // when it's not present in the actual libc.
2005   if (!REAL(epoll_pwait2)) {
2006     errno = errno_ENOSYS;
2007     return -1;
2008   }
2009   if (MustIgnoreInterceptor(thr))
2010     REAL(epoll_pwait2)(epfd, ev, cnt, timeout, sigmask);
2011   if (epfd >= 0)
2012     FdAccess(thr, pc, epfd);
2013   int res = BLOCK_REAL(epoll_pwait2)(epfd, ev, cnt, timeout, sigmask);
2014   if (res > 0 && epfd >= 0)
2015     FdAcquire(thr, pc, epfd);
2016   return res;
2017 }
2018 
2019 #  define TSAN_MAYBE_INTERCEPT_EPOLL \
2020     TSAN_INTERCEPT(epoll_create);    \
2021     TSAN_INTERCEPT(epoll_create1);   \
2022     TSAN_INTERCEPT(epoll_ctl);       \
2023     TSAN_INTERCEPT(epoll_wait);      \
2024     TSAN_INTERCEPT(epoll_pwait);     \
2025     TSAN_INTERCEPT(epoll_pwait2)
2026 #else
2027 #define TSAN_MAYBE_INTERCEPT_EPOLL
2028 #endif
2029 
2030 // The following functions are intercepted merely to process pending signals.
2031 // If program blocks signal X, we must deliver the signal before the function
2032 // returns. Similarly, if program unblocks a signal (or returns from sigsuspend)
2033 // it's better to deliver the signal straight away.
2034 TSAN_INTERCEPTOR(int, sigsuspend, const __sanitizer_sigset_t *mask) {
2035   SCOPED_TSAN_INTERCEPTOR(sigsuspend, mask);
2036   return REAL(sigsuspend)(mask);
2037 }
2038 
2039 TSAN_INTERCEPTOR(int, sigblock, int mask) {
2040   SCOPED_TSAN_INTERCEPTOR(sigblock, mask);
2041   return REAL(sigblock)(mask);
2042 }
2043 
2044 TSAN_INTERCEPTOR(int, sigsetmask, int mask) {
2045   SCOPED_TSAN_INTERCEPTOR(sigsetmask, mask);
2046   return REAL(sigsetmask)(mask);
2047 }
2048 
2049 TSAN_INTERCEPTOR(int, pthread_sigmask, int how, const __sanitizer_sigset_t *set,
2050     __sanitizer_sigset_t *oldset) {
2051   SCOPED_TSAN_INTERCEPTOR(pthread_sigmask, how, set, oldset);
2052   return REAL(pthread_sigmask)(how, set, oldset);
2053 }
2054 
2055 namespace __tsan {
2056 
2057 static void ReportErrnoSpoiling(ThreadState *thr, uptr pc, int sig) {
2058   VarSizeStackTrace stack;
2059   // StackTrace::GetNestInstructionPc(pc) is used because return address is
2060   // expected, OutputReport() will undo this.
2061   ObtainCurrentStack(thr, StackTrace::GetNextInstructionPc(pc), &stack);
2062   ThreadRegistryLock l(&ctx->thread_registry);
2063   ScopedReport rep(ReportTypeErrnoInSignal);
2064   rep.SetSigNum(sig);
2065   if (!IsFiredSuppression(ctx, ReportTypeErrnoInSignal, stack)) {
2066     rep.AddStack(stack, true);
2067     OutputReport(thr, rep);
2068   }
2069 }
2070 
2071 static void CallUserSignalHandler(ThreadState *thr, bool sync, bool acquire,
2072                                   int sig, __sanitizer_siginfo *info,
2073                                   void *uctx) {
2074   CHECK(thr->slot);
2075   __sanitizer_sigaction *sigactions = interceptor_ctx()->sigactions;
2076   if (acquire)
2077     Acquire(thr, 0, (uptr)&sigactions[sig]);
2078   // Signals are generally asynchronous, so if we receive a signals when
2079   // ignores are enabled we should disable ignores. This is critical for sync
2080   // and interceptors, because otherwise we can miss synchronization and report
2081   // false races.
2082   int ignore_reads_and_writes = thr->ignore_reads_and_writes;
2083   int ignore_interceptors = thr->ignore_interceptors;
2084   int ignore_sync = thr->ignore_sync;
2085   // For symbolizer we only process SIGSEGVs synchronously
2086   // (bug in symbolizer or in tsan). But we want to reset
2087   // in_symbolizer to fail gracefully. Symbolizer and user code
2088   // use different memory allocators, so if we don't reset
2089   // in_symbolizer we can get memory allocated with one being
2090   // feed with another, which can cause more crashes.
2091   int in_symbolizer = thr->in_symbolizer;
2092   if (!ctx->after_multithreaded_fork) {
2093     thr->ignore_reads_and_writes = 0;
2094     thr->fast_state.ClearIgnoreBit();
2095     thr->ignore_interceptors = 0;
2096     thr->ignore_sync = 0;
2097     thr->in_symbolizer = 0;
2098   }
2099   // Ensure that the handler does not spoil errno.
2100   const int saved_errno = errno;
2101   errno = 99;
2102   // This code races with sigaction. Be careful to not read sa_sigaction twice.
2103   // Also need to remember pc for reporting before the call,
2104   // because the handler can reset it.
2105   volatile uptr pc = (sigactions[sig].sa_flags & SA_SIGINFO)
2106                          ? (uptr)sigactions[sig].sigaction
2107                          : (uptr)sigactions[sig].handler;
2108   if (pc != sig_dfl && pc != sig_ign) {
2109     // The callback can be either sa_handler or sa_sigaction.
2110     // They have different signatures, but we assume that passing
2111     // additional arguments to sa_handler works and is harmless.
2112     ((__sanitizer_sigactionhandler_ptr)pc)(sig, info, uctx);
2113   }
2114   if (!ctx->after_multithreaded_fork) {
2115     thr->ignore_reads_and_writes = ignore_reads_and_writes;
2116     if (ignore_reads_and_writes)
2117       thr->fast_state.SetIgnoreBit();
2118     thr->ignore_interceptors = ignore_interceptors;
2119     thr->ignore_sync = ignore_sync;
2120     thr->in_symbolizer = in_symbolizer;
2121   }
2122   // We do not detect errno spoiling for SIGTERM,
2123   // because some SIGTERM handlers do spoil errno but reraise SIGTERM,
2124   // tsan reports false positive in such case.
2125   // It's difficult to properly detect this situation (reraise),
2126   // because in async signal processing case (when handler is called directly
2127   // from rtl_generic_sighandler) we have not yet received the reraised
2128   // signal; and it looks too fragile to intercept all ways to reraise a signal.
2129   if (ShouldReport(thr, ReportTypeErrnoInSignal) && !sync && sig != SIGTERM &&
2130       errno != 99)
2131     ReportErrnoSpoiling(thr, pc, sig);
2132   errno = saved_errno;
2133 }
2134 
2135 void ProcessPendingSignalsImpl(ThreadState *thr) {
2136   atomic_store(&thr->pending_signals, 0, memory_order_relaxed);
2137   ThreadSignalContext *sctx = SigCtx(thr);
2138   if (sctx == 0)
2139     return;
2140   atomic_fetch_add(&thr->in_signal_handler, 1, memory_order_relaxed);
2141   internal_sigfillset(&sctx->emptyset);
2142   int res = REAL(pthread_sigmask)(SIG_SETMASK, &sctx->emptyset, &sctx->oldset);
2143   CHECK_EQ(res, 0);
2144   for (int sig = 0; sig < kSigCount; sig++) {
2145     SignalDesc *signal = &sctx->pending_signals[sig];
2146     if (signal->armed) {
2147       signal->armed = false;
2148       CallUserSignalHandler(thr, false, true, sig, &signal->siginfo,
2149                             &signal->ctx);
2150     }
2151   }
2152   res = REAL(pthread_sigmask)(SIG_SETMASK, &sctx->oldset, 0);
2153   CHECK_EQ(res, 0);
2154   atomic_fetch_add(&thr->in_signal_handler, -1, memory_order_relaxed);
2155 }
2156 
2157 }  // namespace __tsan
2158 
2159 static bool is_sync_signal(ThreadSignalContext *sctx, int sig,
2160                            __sanitizer_siginfo *info) {
2161   // If we are sending signal to ourselves, we must process it now.
2162   if (sctx && sig == sctx->int_signal_send)
2163     return true;
2164 #if SANITIZER_HAS_SIGINFO
2165   // POSIX timers can be configured to send any kind of signal; however, it
2166   // doesn't make any sense to consider a timer signal as synchronous!
2167   if (info->si_code == SI_TIMER)
2168     return false;
2169 #endif
2170   return sig == SIGSEGV || sig == SIGBUS || sig == SIGILL || sig == SIGTRAP ||
2171          sig == SIGABRT || sig == SIGFPE || sig == SIGPIPE || sig == SIGSYS;
2172 }
2173 
2174 void sighandler(int sig, __sanitizer_siginfo *info, void *ctx) {
2175   ThreadState *thr = cur_thread_init();
2176   ThreadSignalContext *sctx = SigCtx(thr);
2177   if (sig < 0 || sig >= kSigCount) {
2178     VPrintf(1, "ThreadSanitizer: ignoring signal %d\n", sig);
2179     return;
2180   }
2181   // Don't mess with synchronous signals.
2182   const bool sync = is_sync_signal(sctx, sig, info);
2183   if (sync ||
2184       // If we are in blocking function, we can safely process it now
2185       // (but check if we are in a recursive interceptor,
2186       // i.e. pthread_join()->munmap()).
2187       atomic_load(&thr->in_blocking_func, memory_order_relaxed)) {
2188     atomic_fetch_add(&thr->in_signal_handler, 1, memory_order_relaxed);
2189     if (atomic_load(&thr->in_blocking_func, memory_order_relaxed)) {
2190       atomic_store(&thr->in_blocking_func, 0, memory_order_relaxed);
2191       CallUserSignalHandler(thr, sync, true, sig, info, ctx);
2192       atomic_store(&thr->in_blocking_func, 1, memory_order_relaxed);
2193     } else {
2194       // Be very conservative with when we do acquire in this case.
2195       // It's unsafe to do acquire in async handlers, because ThreadState
2196       // can be in inconsistent state.
2197       // SIGSYS looks relatively safe -- it's synchronous and can actually
2198       // need some global state.
2199       bool acq = (sig == SIGSYS);
2200       CallUserSignalHandler(thr, sync, acq, sig, info, ctx);
2201     }
2202     atomic_fetch_add(&thr->in_signal_handler, -1, memory_order_relaxed);
2203     return;
2204   }
2205 
2206   if (sctx == 0)
2207     return;
2208   SignalDesc *signal = &sctx->pending_signals[sig];
2209   if (signal->armed == false) {
2210     signal->armed = true;
2211     internal_memcpy(&signal->siginfo, info, sizeof(*info));
2212     internal_memcpy(&signal->ctx, ctx, sizeof(signal->ctx));
2213     atomic_store(&thr->pending_signals, 1, memory_order_relaxed);
2214   }
2215 }
2216 
2217 TSAN_INTERCEPTOR(int, raise, int sig) {
2218   SCOPED_TSAN_INTERCEPTOR(raise, sig);
2219   ThreadSignalContext *sctx = SigCtx(thr);
2220   CHECK_NE(sctx, 0);
2221   int prev = sctx->int_signal_send;
2222   sctx->int_signal_send = sig;
2223   int res = REAL(raise)(sig);
2224   CHECK_EQ(sctx->int_signal_send, sig);
2225   sctx->int_signal_send = prev;
2226   return res;
2227 }
2228 
2229 TSAN_INTERCEPTOR(int, kill, int pid, int sig) {
2230   SCOPED_TSAN_INTERCEPTOR(kill, pid, sig);
2231   ThreadSignalContext *sctx = SigCtx(thr);
2232   CHECK_NE(sctx, 0);
2233   int prev = sctx->int_signal_send;
2234   if (pid == (int)internal_getpid()) {
2235     sctx->int_signal_send = sig;
2236   }
2237   int res = REAL(kill)(pid, sig);
2238   if (pid == (int)internal_getpid()) {
2239     CHECK_EQ(sctx->int_signal_send, sig);
2240     sctx->int_signal_send = prev;
2241   }
2242   return res;
2243 }
2244 
2245 TSAN_INTERCEPTOR(int, pthread_kill, void *tid, int sig) {
2246   SCOPED_TSAN_INTERCEPTOR(pthread_kill, tid, sig);
2247   ThreadSignalContext *sctx = SigCtx(thr);
2248   CHECK_NE(sctx, 0);
2249   int prev = sctx->int_signal_send;
2250   bool self = pthread_equal(tid, pthread_self());
2251   if (self)
2252     sctx->int_signal_send = sig;
2253   int res = REAL(pthread_kill)(tid, sig);
2254   if (self) {
2255     CHECK_EQ(sctx->int_signal_send, sig);
2256     sctx->int_signal_send = prev;
2257   }
2258   return res;
2259 }
2260 
2261 TSAN_INTERCEPTOR(int, gettimeofday, void *tv, void *tz) {
2262   SCOPED_TSAN_INTERCEPTOR(gettimeofday, tv, tz);
2263   // It's intercepted merely to process pending signals.
2264   return REAL(gettimeofday)(tv, tz);
2265 }
2266 
2267 TSAN_INTERCEPTOR(int, getaddrinfo, void *node, void *service,
2268     void *hints, void *rv) {
2269   SCOPED_TSAN_INTERCEPTOR(getaddrinfo, node, service, hints, rv);
2270   // We miss atomic synchronization in getaddrinfo,
2271   // and can report false race between malloc and free
2272   // inside of getaddrinfo. So ignore memory accesses.
2273   ThreadIgnoreBegin(thr, pc);
2274   int res = REAL(getaddrinfo)(node, service, hints, rv);
2275   ThreadIgnoreEnd(thr);
2276   return res;
2277 }
2278 
2279 TSAN_INTERCEPTOR(int, fork, int fake) {
2280   if (in_symbolizer())
2281     return REAL(fork)(fake);
2282   SCOPED_INTERCEPTOR_RAW(fork, fake);
2283   return REAL(fork)(fake);
2284 }
2285 
2286 void atfork_prepare() {
2287   if (in_symbolizer())
2288     return;
2289   ThreadState *thr = cur_thread();
2290   const uptr pc = StackTrace::GetCurrentPc();
2291   ForkBefore(thr, pc);
2292 }
2293 
2294 void atfork_parent() {
2295   if (in_symbolizer())
2296     return;
2297   ThreadState *thr = cur_thread();
2298   const uptr pc = StackTrace::GetCurrentPc();
2299   ForkParentAfter(thr, pc);
2300 }
2301 
2302 void atfork_child() {
2303   if (in_symbolizer())
2304     return;
2305   ThreadState *thr = cur_thread();
2306   const uptr pc = StackTrace::GetCurrentPc();
2307   ForkChildAfter(thr, pc, true);
2308   FdOnFork(thr, pc);
2309 }
2310 
2311 #if !SANITIZER_IOS
2312 TSAN_INTERCEPTOR(int, vfork, int fake) {
2313   // Some programs (e.g. openjdk) call close for all file descriptors
2314   // in the child process. Under tsan it leads to false positives, because
2315   // address space is shared, so the parent process also thinks that
2316   // the descriptors are closed (while they are actually not).
2317   // This leads to false positives due to missed synchronization.
2318   // Strictly saying this is undefined behavior, because vfork child is not
2319   // allowed to call any functions other than exec/exit. But this is what
2320   // openjdk does, so we want to handle it.
2321   // We could disable interceptors in the child process. But it's not possible
2322   // to simply intercept and wrap vfork, because vfork child is not allowed
2323   // to return from the function that calls vfork, and that's exactly what
2324   // we would do. So this would require some assembly trickery as well.
2325   // Instead we simply turn vfork into fork.
2326   return WRAP(fork)(fake);
2327 }
2328 #endif
2329 
2330 #if SANITIZER_LINUX
2331 TSAN_INTERCEPTOR(int, clone, int (*fn)(void *), void *stack, int flags,
2332                  void *arg, int *parent_tid, void *tls, pid_t *child_tid) {
2333   SCOPED_INTERCEPTOR_RAW(clone, fn, stack, flags, arg, parent_tid, tls,
2334                          child_tid);
2335   struct Arg {
2336     int (*fn)(void *);
2337     void *arg;
2338   };
2339   auto wrapper = +[](void *p) -> int {
2340     auto *thr = cur_thread();
2341     uptr pc = GET_CURRENT_PC();
2342     // Start the background thread for fork, but not for clone.
2343     // For fork we did this always and it's known to work (or user code has
2344     // adopted). But if we do this for the new clone interceptor some code
2345     // (sandbox2) fails. So model we used to do for years and don't start the
2346     // background thread after clone.
2347     ForkChildAfter(thr, pc, false);
2348     FdOnFork(thr, pc);
2349     auto *arg = static_cast<Arg *>(p);
2350     return arg->fn(arg->arg);
2351   };
2352   ForkBefore(thr, pc);
2353   Arg arg_wrapper = {fn, arg};
2354   int pid = REAL(clone)(wrapper, stack, flags, &arg_wrapper, parent_tid, tls,
2355                         child_tid);
2356   ForkParentAfter(thr, pc);
2357   return pid;
2358 }
2359 #endif
2360 
2361 #if !SANITIZER_APPLE && !SANITIZER_ANDROID
2362 typedef int (*dl_iterate_phdr_cb_t)(__sanitizer_dl_phdr_info *info, SIZE_T size,
2363                                     void *data);
2364 struct dl_iterate_phdr_data {
2365   ThreadState *thr;
2366   uptr pc;
2367   dl_iterate_phdr_cb_t cb;
2368   void *data;
2369 };
2370 
2371 static bool IsAppNotRodata(uptr addr) {
2372   return IsAppMem(addr) && *MemToShadow(addr) != Shadow::kRodata;
2373 }
2374 
2375 static int dl_iterate_phdr_cb(__sanitizer_dl_phdr_info *info, SIZE_T size,
2376                               void *data) {
2377   dl_iterate_phdr_data *cbdata = (dl_iterate_phdr_data *)data;
2378   // dlopen/dlclose allocate/free dynamic-linker-internal memory, which is later
2379   // accessible in dl_iterate_phdr callback. But we don't see synchronization
2380   // inside of dynamic linker, so we "unpoison" it here in order to not
2381   // produce false reports. Ignoring malloc/free in dlopen/dlclose is not enough
2382   // because some libc functions call __libc_dlopen.
2383   if (info && IsAppNotRodata((uptr)info->dlpi_name))
2384     MemoryResetRange(cbdata->thr, cbdata->pc, (uptr)info->dlpi_name,
2385                      internal_strlen(info->dlpi_name));
2386   int res = cbdata->cb(info, size, cbdata->data);
2387   // Perform the check one more time in case info->dlpi_name was overwritten
2388   // by user callback.
2389   if (info && IsAppNotRodata((uptr)info->dlpi_name))
2390     MemoryResetRange(cbdata->thr, cbdata->pc, (uptr)info->dlpi_name,
2391                      internal_strlen(info->dlpi_name));
2392   return res;
2393 }
2394 
2395 TSAN_INTERCEPTOR(int, dl_iterate_phdr, dl_iterate_phdr_cb_t cb, void *data) {
2396   SCOPED_TSAN_INTERCEPTOR(dl_iterate_phdr, cb, data);
2397   dl_iterate_phdr_data cbdata;
2398   cbdata.thr = thr;
2399   cbdata.pc = pc;
2400   cbdata.cb = cb;
2401   cbdata.data = data;
2402   int res = REAL(dl_iterate_phdr)(dl_iterate_phdr_cb, &cbdata);
2403   return res;
2404 }
2405 #endif
2406 
2407 static int OnExit(ThreadState *thr) {
2408   int status = Finalize(thr);
2409   FlushStreams();
2410   return status;
2411 }
2412 
2413 #if !SANITIZER_APPLE
2414 static void HandleRecvmsg(ThreadState *thr, uptr pc,
2415     __sanitizer_msghdr *msg) {
2416   int fds[64];
2417   int cnt = ExtractRecvmsgFDs(msg, fds, ARRAY_SIZE(fds));
2418   for (int i = 0; i < cnt; i++)
2419     FdEventCreate(thr, pc, fds[i]);
2420 }
2421 #endif
2422 
2423 #include "sanitizer_common/sanitizer_platform_interceptors.h"
2424 // Causes interceptor recursion (getaddrinfo() and fopen())
2425 #undef SANITIZER_INTERCEPT_GETADDRINFO
2426 // We define our own.
2427 #if SANITIZER_INTERCEPT_TLS_GET_ADDR
2428 #define NEED_TLS_GET_ADDR
2429 #endif
2430 #undef SANITIZER_INTERCEPT_TLS_GET_ADDR
2431 #define SANITIZER_INTERCEPT_TLS_GET_OFFSET 1
2432 #undef SANITIZER_INTERCEPT_PTHREAD_SIGMASK
2433 
2434 #define COMMON_INTERCEPT_FUNCTION_VER(name, ver)                          \
2435   INTERCEPT_FUNCTION_VER(name, ver)
2436 #define COMMON_INTERCEPT_FUNCTION_VER_UNVERSIONED_FALLBACK(name, ver) \
2437   (INTERCEPT_FUNCTION_VER(name, ver) || INTERCEPT_FUNCTION(name))
2438 
2439 #define COMMON_INTERCEPTOR_ENTER_NOIGNORE(ctx, func, ...) \
2440   SCOPED_INTERCEPTOR_RAW(func, __VA_ARGS__);              \
2441   TsanInterceptorContext _ctx = {thr, pc};                \
2442   ctx = (void *)&_ctx;                                    \
2443   (void)ctx;
2444 
2445 #define COMMON_INTERCEPTOR_FILE_OPEN(ctx, file, path) \
2446   if (path)                                           \
2447     Acquire(thr, pc, File2addr(path));                \
2448   if (file) {                                         \
2449     int fd = fileno_unlocked(file);                   \
2450     if (fd >= 0) FdFileCreate(thr, pc, fd);           \
2451   }
2452 
2453 #define COMMON_INTERCEPTOR_FILE_CLOSE(ctx, file) \
2454   if (file) {                                    \
2455     int fd = fileno_unlocked(file);              \
2456     FdClose(thr, pc, fd);                        \
2457   }
2458 
2459 #define COMMON_INTERCEPTOR_DLOPEN(filename, flag) \
2460   ({                                              \
2461     CheckNoDeepBind(filename, flag);              \
2462     ThreadIgnoreBegin(thr, 0);                    \
2463     void *res = REAL(dlopen)(filename, flag);     \
2464     ThreadIgnoreEnd(thr);                         \
2465     res;                                          \
2466   })
2467 
2468 // Ignore interceptors in OnLibraryLoaded()/Unloaded().  These hooks use code
2469 // (ListOfModules::init, MemoryMappingLayout::DumpListOfModules) that make
2470 // intercepted calls, which can cause deadlockes with ReportRace() which also
2471 // uses this code.
2472 #define COMMON_INTERCEPTOR_LIBRARY_LOADED(filename, handle) \
2473   ({                                                        \
2474     ScopedIgnoreInterceptors ignore_interceptors;           \
2475     libignore()->OnLibraryLoaded(filename);                 \
2476   })
2477 
2478 #define COMMON_INTERCEPTOR_LIBRARY_UNLOADED()     \
2479   ({                                              \
2480     ScopedIgnoreInterceptors ignore_interceptors; \
2481     libignore()->OnLibraryUnloaded();             \
2482   })
2483 
2484 #define COMMON_INTERCEPTOR_ACQUIRE(ctx, u) \
2485   Acquire(((TsanInterceptorContext *) ctx)->thr, pc, u)
2486 
2487 #define COMMON_INTERCEPTOR_RELEASE(ctx, u) \
2488   Release(((TsanInterceptorContext *) ctx)->thr, pc, u)
2489 
2490 #define COMMON_INTERCEPTOR_DIR_ACQUIRE(ctx, path) \
2491   Acquire(((TsanInterceptorContext *) ctx)->thr, pc, Dir2addr(path))
2492 
2493 #define COMMON_INTERCEPTOR_FD_ACQUIRE(ctx, fd) \
2494   FdAcquire(((TsanInterceptorContext *) ctx)->thr, pc, fd)
2495 
2496 #define COMMON_INTERCEPTOR_FD_RELEASE(ctx, fd) \
2497   FdRelease(((TsanInterceptorContext *) ctx)->thr, pc, fd)
2498 
2499 #define COMMON_INTERCEPTOR_FD_ACCESS(ctx, fd) \
2500   FdAccess(((TsanInterceptorContext *) ctx)->thr, pc, fd)
2501 
2502 #define COMMON_INTERCEPTOR_FD_SOCKET_ACCEPT(ctx, fd, newfd) \
2503   FdSocketAccept(((TsanInterceptorContext *) ctx)->thr, pc, fd, newfd)
2504 
2505 #define COMMON_INTERCEPTOR_SET_THREAD_NAME(ctx, name) \
2506   ThreadSetName(((TsanInterceptorContext *) ctx)->thr, name)
2507 
2508 #define COMMON_INTERCEPTOR_SET_PTHREAD_NAME(ctx, thread, name)         \
2509   if (pthread_equal(pthread_self(), reinterpret_cast<void *>(thread))) \
2510     COMMON_INTERCEPTOR_SET_THREAD_NAME(ctx, name);                     \
2511   else                                                                 \
2512     __tsan::ctx->thread_registry.SetThreadNameByUserId(thread, name)
2513 
2514 #define COMMON_INTERCEPTOR_BLOCK_REAL(name) BLOCK_REAL(name)
2515 
2516 #define COMMON_INTERCEPTOR_ON_EXIT(ctx) \
2517   OnExit(((TsanInterceptorContext *) ctx)->thr)
2518 
2519 #define COMMON_INTERCEPTOR_MMAP_IMPL(ctx, mmap, addr, sz, prot, flags, fd,  \
2520                                      off)                                   \
2521   do {                                                                      \
2522     return mmap_interceptor(thr, pc, REAL(mmap), addr, sz, prot, flags, fd, \
2523                             off);                                           \
2524   } while (false)
2525 
2526 #define COMMON_INTERCEPTOR_MUNMAP_IMPL(ctx, addr, sz)           \
2527   do {                                                          \
2528     return munmap_interceptor(thr, pc, REAL(munmap), addr, sz); \
2529   } while (false)
2530 
2531 #if !SANITIZER_APPLE
2532 #define COMMON_INTERCEPTOR_HANDLE_RECVMSG(ctx, msg) \
2533   HandleRecvmsg(((TsanInterceptorContext *)ctx)->thr, \
2534       ((TsanInterceptorContext *)ctx)->pc, msg)
2535 #endif
2536 
2537 #define COMMON_INTERCEPTOR_GET_TLS_RANGE(begin, end)                           \
2538   if (TsanThread *t = GetCurrentThread()) {                                    \
2539     *begin = t->tls_begin();                                                   \
2540     *end = t->tls_end();                                                       \
2541   } else {                                                                     \
2542     *begin = *end = 0;                                                         \
2543   }
2544 
2545 #define COMMON_INTERCEPTOR_USER_CALLBACK_START() \
2546   SCOPED_TSAN_INTERCEPTOR_USER_CALLBACK_START()
2547 
2548 #define COMMON_INTERCEPTOR_USER_CALLBACK_END() \
2549   SCOPED_TSAN_INTERCEPTOR_USER_CALLBACK_END()
2550 
2551 #include "sanitizer_common/sanitizer_common_interceptors.inc"
2552 
2553 static int sigaction_impl(int sig, const __sanitizer_sigaction *act,
2554                           __sanitizer_sigaction *old);
2555 static __sanitizer_sighandler_ptr signal_impl(int sig,
2556                                               __sanitizer_sighandler_ptr h);
2557 
2558 #define SIGNAL_INTERCEPTOR_SIGACTION_IMPL(signo, act, oldact) \
2559   { return sigaction_impl(signo, act, oldact); }
2560 
2561 #define SIGNAL_INTERCEPTOR_SIGNAL_IMPL(func, signo, handler) \
2562   { return (uptr)signal_impl(signo, (__sanitizer_sighandler_ptr)handler); }
2563 
2564 #define SIGNAL_INTERCEPTOR_ENTER() LazyInitialize(cur_thread_init())
2565 
2566 #include "sanitizer_common/sanitizer_signal_interceptors.inc"
2567 
2568 int sigaction_impl(int sig, const __sanitizer_sigaction *act,
2569                    __sanitizer_sigaction *old) {
2570   // Note: if we call REAL(sigaction) directly for any reason without proxying
2571   // the signal handler through sighandler, very bad things will happen.
2572   // The handler will run synchronously and corrupt tsan per-thread state.
2573   SCOPED_INTERCEPTOR_RAW(sigaction, sig, act, old);
2574   if (sig <= 0 || sig >= kSigCount) {
2575     errno = errno_EINVAL;
2576     return -1;
2577   }
2578   __sanitizer_sigaction *sigactions = interceptor_ctx()->sigactions;
2579   __sanitizer_sigaction old_stored;
2580   if (old) internal_memcpy(&old_stored, &sigactions[sig], sizeof(old_stored));
2581   __sanitizer_sigaction newact;
2582   if (act) {
2583     // Copy act into sigactions[sig].
2584     // Can't use struct copy, because compiler can emit call to memcpy.
2585     // Can't use internal_memcpy, because it copies byte-by-byte,
2586     // and signal handler reads the handler concurrently. It can read
2587     // some bytes from old value and some bytes from new value.
2588     // Use volatile to prevent insertion of memcpy.
2589     sigactions[sig].handler =
2590         *(volatile __sanitizer_sighandler_ptr const *)&act->handler;
2591     sigactions[sig].sa_flags = *(volatile int const *)&act->sa_flags;
2592     internal_memcpy(&sigactions[sig].sa_mask, &act->sa_mask,
2593                     sizeof(sigactions[sig].sa_mask));
2594 #if !SANITIZER_FREEBSD && !SANITIZER_APPLE && !SANITIZER_NETBSD
2595     sigactions[sig].sa_restorer = act->sa_restorer;
2596 #endif
2597     internal_memcpy(&newact, act, sizeof(newact));
2598     internal_sigfillset(&newact.sa_mask);
2599     if ((act->sa_flags & SA_SIGINFO) ||
2600         ((uptr)act->handler != sig_ign && (uptr)act->handler != sig_dfl)) {
2601       newact.sa_flags |= SA_SIGINFO;
2602       newact.sigaction = sighandler;
2603     }
2604     ReleaseStore(thr, pc, (uptr)&sigactions[sig]);
2605     act = &newact;
2606   }
2607   int res = REAL(sigaction)(sig, act, old);
2608   if (res == 0 && old && old->sigaction == sighandler)
2609     internal_memcpy(old, &old_stored, sizeof(*old));
2610   return res;
2611 }
2612 
2613 static __sanitizer_sighandler_ptr signal_impl(int sig,
2614                                               __sanitizer_sighandler_ptr h) {
2615   __sanitizer_sigaction act;
2616   act.handler = h;
2617   internal_memset(&act.sa_mask, -1, sizeof(act.sa_mask));
2618   act.sa_flags = 0;
2619   __sanitizer_sigaction old;
2620   int res = sigaction_symname(sig, &act, &old);
2621   if (res) return (__sanitizer_sighandler_ptr)sig_err;
2622   return old.handler;
2623 }
2624 
2625 #define TSAN_SYSCALL()             \
2626   ThreadState *thr = cur_thread(); \
2627   if (thr->ignore_interceptors)    \
2628     return;                        \
2629   ScopedSyscall scoped_syscall(thr)
2630 
2631 struct ScopedSyscall {
2632   ThreadState *thr;
2633 
2634   explicit ScopedSyscall(ThreadState *thr) : thr(thr) { LazyInitialize(thr); }
2635 
2636   ~ScopedSyscall() {
2637     ProcessPendingSignals(thr);
2638   }
2639 };
2640 
2641 #if !SANITIZER_FREEBSD && !SANITIZER_APPLE
2642 static void syscall_access_range(uptr pc, uptr p, uptr s, bool write) {
2643   TSAN_SYSCALL();
2644   MemoryAccessRange(thr, pc, p, s, write);
2645 }
2646 
2647 static USED void syscall_acquire(uptr pc, uptr addr) {
2648   TSAN_SYSCALL();
2649   Acquire(thr, pc, addr);
2650   DPrintf("syscall_acquire(0x%zx))\n", addr);
2651 }
2652 
2653 static USED void syscall_release(uptr pc, uptr addr) {
2654   TSAN_SYSCALL();
2655   DPrintf("syscall_release(0x%zx)\n", addr);
2656   Release(thr, pc, addr);
2657 }
2658 
2659 static void syscall_fd_close(uptr pc, int fd) {
2660   auto *thr = cur_thread();
2661   FdClose(thr, pc, fd);
2662 }
2663 
2664 static USED void syscall_fd_acquire(uptr pc, int fd) {
2665   TSAN_SYSCALL();
2666   FdAcquire(thr, pc, fd);
2667   DPrintf("syscall_fd_acquire(%d)\n", fd);
2668 }
2669 
2670 static USED void syscall_fd_release(uptr pc, int fd) {
2671   TSAN_SYSCALL();
2672   DPrintf("syscall_fd_release(%d)\n", fd);
2673   FdRelease(thr, pc, fd);
2674 }
2675 
2676 static void syscall_pre_fork(uptr pc) { ForkBefore(cur_thread(), pc); }
2677 
2678 static void syscall_post_fork(uptr pc, int pid) {
2679   ThreadState *thr = cur_thread();
2680   if (pid == 0) {
2681     // child
2682     ForkChildAfter(thr, pc, true);
2683     FdOnFork(thr, pc);
2684   } else if (pid > 0) {
2685     // parent
2686     ForkParentAfter(thr, pc);
2687   } else {
2688     // error
2689     ForkParentAfter(thr, pc);
2690   }
2691 }
2692 #endif
2693 
2694 #define COMMON_SYSCALL_PRE_READ_RANGE(p, s) \
2695   syscall_access_range(GET_CALLER_PC(), (uptr)(p), (uptr)(s), false)
2696 
2697 #define COMMON_SYSCALL_PRE_WRITE_RANGE(p, s) \
2698   syscall_access_range(GET_CALLER_PC(), (uptr)(p), (uptr)(s), true)
2699 
2700 #define COMMON_SYSCALL_POST_READ_RANGE(p, s) \
2701   do {                                       \
2702     (void)(p);                               \
2703     (void)(s);                               \
2704   } while (false)
2705 
2706 #define COMMON_SYSCALL_POST_WRITE_RANGE(p, s) \
2707   do {                                        \
2708     (void)(p);                                \
2709     (void)(s);                                \
2710   } while (false)
2711 
2712 #define COMMON_SYSCALL_ACQUIRE(addr) \
2713     syscall_acquire(GET_CALLER_PC(), (uptr)(addr))
2714 
2715 #define COMMON_SYSCALL_RELEASE(addr) \
2716     syscall_release(GET_CALLER_PC(), (uptr)(addr))
2717 
2718 #define COMMON_SYSCALL_FD_CLOSE(fd) syscall_fd_close(GET_CALLER_PC(), fd)
2719 
2720 #define COMMON_SYSCALL_FD_ACQUIRE(fd) syscall_fd_acquire(GET_CALLER_PC(), fd)
2721 
2722 #define COMMON_SYSCALL_FD_RELEASE(fd) syscall_fd_release(GET_CALLER_PC(), fd)
2723 
2724 #define COMMON_SYSCALL_PRE_FORK() \
2725   syscall_pre_fork(GET_CALLER_PC())
2726 
2727 #define COMMON_SYSCALL_POST_FORK(res) \
2728   syscall_post_fork(GET_CALLER_PC(), res)
2729 
2730 #include "sanitizer_common/sanitizer_common_syscalls.inc"
2731 #include "sanitizer_common/sanitizer_syscalls_netbsd.inc"
2732 
2733 #ifdef NEED_TLS_GET_ADDR
2734 
2735 static void handle_tls_addr(void *arg, void *res) {
2736   ThreadState *thr = cur_thread();
2737   if (!thr)
2738     return;
2739   DTLS::DTV *dtv = DTLS_on_tls_get_addr(arg, res, thr->tls_addr,
2740                                         thr->tls_addr + thr->tls_size);
2741   if (!dtv)
2742     return;
2743   // New DTLS block has been allocated.
2744   MemoryResetRange(thr, 0, dtv->beg, dtv->size);
2745 }
2746 
2747 #if !SANITIZER_S390
2748 // Define own interceptor instead of sanitizer_common's for three reasons:
2749 // 1. It must not process pending signals.
2750 //    Signal handlers may contain MOVDQA instruction (see below).
2751 // 2. It must be as simple as possible to not contain MOVDQA.
2752 // 3. Sanitizer_common version uses COMMON_INTERCEPTOR_INITIALIZE_RANGE which
2753 //    is empty for tsan (meant only for msan).
2754 // Note: __tls_get_addr can be called with mis-aligned stack due to:
2755 // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58066
2756 // So the interceptor must work with mis-aligned stack, in particular, does not
2757 // execute MOVDQA with stack addresses.
2758 TSAN_INTERCEPTOR(void *, __tls_get_addr, void *arg) {
2759   void *res = REAL(__tls_get_addr)(arg);
2760   handle_tls_addr(arg, res);
2761   return res;
2762 }
2763 #else // SANITIZER_S390
2764 TSAN_INTERCEPTOR(uptr, __tls_get_addr_internal, void *arg) {
2765   uptr res = __tls_get_offset_wrapper(arg, REAL(__tls_get_offset));
2766   char *tp = static_cast<char *>(__builtin_thread_pointer());
2767   handle_tls_addr(arg, res + tp);
2768   return res;
2769 }
2770 #endif
2771 #endif
2772 
2773 #if SANITIZER_NETBSD
2774 TSAN_INTERCEPTOR(void, _lwp_exit) {
2775   SCOPED_TSAN_INTERCEPTOR(_lwp_exit);
2776   DestroyThreadState();
2777   REAL(_lwp_exit)();
2778 }
2779 #define TSAN_MAYBE_INTERCEPT__LWP_EXIT TSAN_INTERCEPT(_lwp_exit)
2780 #else
2781 #define TSAN_MAYBE_INTERCEPT__LWP_EXIT
2782 #endif
2783 
2784 #if SANITIZER_FREEBSD
2785 TSAN_INTERCEPTOR(void, thr_exit, tid_t *state) {
2786   SCOPED_TSAN_INTERCEPTOR(thr_exit, state);
2787   DestroyThreadState();
2788   REAL(thr_exit(state));
2789 }
2790 #define TSAN_MAYBE_INTERCEPT_THR_EXIT TSAN_INTERCEPT(thr_exit)
2791 #else
2792 #define TSAN_MAYBE_INTERCEPT_THR_EXIT
2793 #endif
2794 
2795 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, cond_init, void *c, void *a)
2796 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, cond_destroy, void *c)
2797 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, cond_signal, void *c)
2798 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, cond_broadcast, void *c)
2799 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, cond_wait, void *c, void *m)
2800 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, mutex_init, void *m, void *a)
2801 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, mutex_destroy, void *m)
2802 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, mutex_lock, void *m)
2803 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, mutex_trylock, void *m)
2804 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, mutex_unlock, void *m)
2805 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, rwlock_init, void *l, void *a)
2806 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, rwlock_destroy, void *l)
2807 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, rwlock_rdlock, void *l)
2808 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, rwlock_tryrdlock, void *l)
2809 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, rwlock_wrlock, void *l)
2810 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, rwlock_trywrlock, void *l)
2811 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, rwlock_unlock, void *l)
2812 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, once, void *o, void (*i)())
2813 TSAN_INTERCEPTOR_FREEBSD_ALIAS(int, sigmask, int f, void *n, void *o)
2814 
2815 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, cond_init, void *c, void *a)
2816 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, cond_signal, void *c)
2817 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, cond_broadcast, void *c)
2818 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, cond_wait, void *c, void *m)
2819 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, cond_destroy, void *c)
2820 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, mutex_init, void *m, void *a)
2821 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, mutex_destroy, void *m)
2822 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, mutex_lock, void *m)
2823 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, mutex_trylock, void *m)
2824 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, mutex_unlock, void *m)
2825 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, rwlock_init, void *m, void *a)
2826 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, rwlock_destroy, void *m)
2827 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, rwlock_rdlock, void *m)
2828 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, rwlock_tryrdlock, void *m)
2829 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, rwlock_wrlock, void *m)
2830 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, rwlock_trywrlock, void *m)
2831 TSAN_INTERCEPTOR_NETBSD_ALIAS(int, rwlock_unlock, void *m)
2832 TSAN_INTERCEPTOR_NETBSD_ALIAS_THR(int, once, void *o, void (*f)())
2833 TSAN_INTERCEPTOR_NETBSD_ALIAS_THR2(int, sigsetmask, sigmask, int a, void *b,
2834   void *c)
2835 
2836 namespace __tsan {
2837 
2838 static void finalize(void *arg) {
2839   ThreadState *thr = cur_thread();
2840   int status = Finalize(thr);
2841   // Make sure the output is not lost.
2842   FlushStreams();
2843   if (status)
2844     Die();
2845 }
2846 
2847 #if !SANITIZER_APPLE && !SANITIZER_ANDROID
2848 static void unreachable() {
2849   Report("FATAL: ThreadSanitizer: unreachable called\n");
2850   Die();
2851 }
2852 #endif
2853 
2854 // Define default implementation since interception of libdispatch  is optional.
2855 SANITIZER_WEAK_ATTRIBUTE void InitializeLibdispatchInterceptors() {}
2856 
2857 void InitializeInterceptors() {
2858 #if !SANITIZER_APPLE
2859   // We need to setup it early, because functions like dlsym() can call it.
2860   REAL(memset) = internal_memset;
2861   REAL(memcpy) = internal_memcpy;
2862 #endif
2863 
2864   new(interceptor_ctx()) InterceptorContext();
2865 
2866   InitializeCommonInterceptors();
2867   InitializeSignalInterceptors();
2868   InitializeLibdispatchInterceptors();
2869 
2870 #if !SANITIZER_APPLE
2871   InitializeSetjmpInterceptors();
2872 #endif
2873 
2874   TSAN_INTERCEPT(longjmp_symname);
2875   TSAN_INTERCEPT(siglongjmp_symname);
2876 #if SANITIZER_NETBSD
2877   TSAN_INTERCEPT(_longjmp);
2878 #endif
2879 
2880   TSAN_INTERCEPT(malloc);
2881   TSAN_INTERCEPT(__libc_memalign);
2882   TSAN_INTERCEPT(calloc);
2883   TSAN_INTERCEPT(realloc);
2884   TSAN_INTERCEPT(reallocarray);
2885   TSAN_INTERCEPT(free);
2886   TSAN_INTERCEPT(cfree);
2887   TSAN_INTERCEPT(munmap);
2888   TSAN_MAYBE_INTERCEPT_MEMALIGN;
2889   TSAN_INTERCEPT(valloc);
2890   TSAN_MAYBE_INTERCEPT_PVALLOC;
2891   TSAN_INTERCEPT(posix_memalign);
2892 
2893   TSAN_INTERCEPT(strcpy);
2894   TSAN_INTERCEPT(strncpy);
2895   TSAN_INTERCEPT(strdup);
2896 
2897   TSAN_INTERCEPT(pthread_create);
2898   TSAN_INTERCEPT(pthread_join);
2899   TSAN_INTERCEPT(pthread_detach);
2900   TSAN_INTERCEPT(pthread_exit);
2901   #if SANITIZER_LINUX
2902   TSAN_INTERCEPT(pthread_tryjoin_np);
2903   TSAN_INTERCEPT(pthread_timedjoin_np);
2904   #endif
2905 
2906   TSAN_INTERCEPT_VER(pthread_cond_init, PTHREAD_ABI_BASE);
2907   TSAN_INTERCEPT_VER(pthread_cond_signal, PTHREAD_ABI_BASE);
2908   TSAN_INTERCEPT_VER(pthread_cond_broadcast, PTHREAD_ABI_BASE);
2909   TSAN_INTERCEPT_VER(pthread_cond_wait, PTHREAD_ABI_BASE);
2910   TSAN_INTERCEPT_VER(pthread_cond_timedwait, PTHREAD_ABI_BASE);
2911   TSAN_INTERCEPT_VER(pthread_cond_destroy, PTHREAD_ABI_BASE);
2912 
2913   TSAN_MAYBE_PTHREAD_COND_CLOCKWAIT;
2914 
2915   TSAN_INTERCEPT(pthread_mutex_init);
2916   TSAN_INTERCEPT(pthread_mutex_destroy);
2917   TSAN_INTERCEPT(pthread_mutex_lock);
2918   TSAN_INTERCEPT(pthread_mutex_trylock);
2919   TSAN_INTERCEPT(pthread_mutex_timedlock);
2920   TSAN_INTERCEPT(pthread_mutex_unlock);
2921 #if SANITIZER_LINUX
2922   TSAN_INTERCEPT(pthread_mutex_clocklock);
2923 #endif
2924 #if SANITIZER_GLIBC
2925 #  if !__GLIBC_PREREQ(2, 34)
2926   TSAN_INTERCEPT(__pthread_mutex_lock);
2927   TSAN_INTERCEPT(__pthread_mutex_unlock);
2928 #  endif
2929 #endif
2930 
2931   TSAN_INTERCEPT(pthread_spin_init);
2932   TSAN_INTERCEPT(pthread_spin_destroy);
2933   TSAN_INTERCEPT(pthread_spin_lock);
2934   TSAN_INTERCEPT(pthread_spin_trylock);
2935   TSAN_INTERCEPT(pthread_spin_unlock);
2936 
2937   TSAN_INTERCEPT(pthread_rwlock_init);
2938   TSAN_INTERCEPT(pthread_rwlock_destroy);
2939   TSAN_INTERCEPT(pthread_rwlock_rdlock);
2940   TSAN_INTERCEPT(pthread_rwlock_tryrdlock);
2941   TSAN_INTERCEPT(pthread_rwlock_timedrdlock);
2942   TSAN_INTERCEPT(pthread_rwlock_wrlock);
2943   TSAN_INTERCEPT(pthread_rwlock_trywrlock);
2944   TSAN_INTERCEPT(pthread_rwlock_timedwrlock);
2945   TSAN_INTERCEPT(pthread_rwlock_unlock);
2946 
2947   TSAN_INTERCEPT(pthread_barrier_init);
2948   TSAN_INTERCEPT(pthread_barrier_destroy);
2949   TSAN_INTERCEPT(pthread_barrier_wait);
2950 
2951   TSAN_INTERCEPT(pthread_once);
2952 
2953   TSAN_INTERCEPT(fstat);
2954   TSAN_MAYBE_INTERCEPT___FXSTAT;
2955   TSAN_MAYBE_INTERCEPT_FSTAT64;
2956   TSAN_MAYBE_INTERCEPT___FXSTAT64;
2957   TSAN_INTERCEPT(open);
2958   TSAN_MAYBE_INTERCEPT_OPEN64;
2959   TSAN_INTERCEPT(creat);
2960   TSAN_MAYBE_INTERCEPT_CREAT64;
2961   TSAN_INTERCEPT(dup);
2962   TSAN_INTERCEPT(dup2);
2963   TSAN_INTERCEPT(dup3);
2964   TSAN_MAYBE_INTERCEPT_EVENTFD;
2965   TSAN_MAYBE_INTERCEPT_SIGNALFD;
2966   TSAN_MAYBE_INTERCEPT_INOTIFY_INIT;
2967   TSAN_MAYBE_INTERCEPT_INOTIFY_INIT1;
2968   TSAN_INTERCEPT(socket);
2969   TSAN_INTERCEPT(socketpair);
2970   TSAN_INTERCEPT(connect);
2971   TSAN_INTERCEPT(bind);
2972   TSAN_INTERCEPT(listen);
2973   TSAN_MAYBE_INTERCEPT_EPOLL;
2974   TSAN_INTERCEPT(close);
2975   TSAN_MAYBE_INTERCEPT___CLOSE;
2976   TSAN_MAYBE_INTERCEPT___RES_ICLOSE;
2977   TSAN_INTERCEPT(pipe);
2978   TSAN_INTERCEPT(pipe2);
2979 
2980   TSAN_INTERCEPT(unlink);
2981   TSAN_INTERCEPT(tmpfile);
2982   TSAN_MAYBE_INTERCEPT_TMPFILE64;
2983   TSAN_INTERCEPT(abort);
2984   TSAN_INTERCEPT(rmdir);
2985   TSAN_INTERCEPT(closedir);
2986 
2987   TSAN_INTERCEPT(sigsuspend);
2988   TSAN_INTERCEPT(sigblock);
2989   TSAN_INTERCEPT(sigsetmask);
2990   TSAN_INTERCEPT(pthread_sigmask);
2991   TSAN_INTERCEPT(raise);
2992   TSAN_INTERCEPT(kill);
2993   TSAN_INTERCEPT(pthread_kill);
2994   TSAN_INTERCEPT(sleep);
2995   TSAN_INTERCEPT(usleep);
2996   TSAN_INTERCEPT(nanosleep);
2997   TSAN_INTERCEPT(pause);
2998   TSAN_INTERCEPT(gettimeofday);
2999   TSAN_INTERCEPT(getaddrinfo);
3000 
3001   TSAN_INTERCEPT(fork);
3002   TSAN_INTERCEPT(vfork);
3003 #if SANITIZER_LINUX
3004   TSAN_INTERCEPT(clone);
3005 #endif
3006 #if !SANITIZER_ANDROID
3007   TSAN_INTERCEPT(dl_iterate_phdr);
3008 #endif
3009   TSAN_MAYBE_INTERCEPT_ON_EXIT;
3010   TSAN_INTERCEPT(__cxa_atexit);
3011   TSAN_INTERCEPT(_exit);
3012 
3013 #ifdef NEED_TLS_GET_ADDR
3014 #if !SANITIZER_S390
3015   TSAN_INTERCEPT(__tls_get_addr);
3016 #else
3017   TSAN_INTERCEPT(__tls_get_addr_internal);
3018   TSAN_INTERCEPT(__tls_get_offset);
3019 #endif
3020 #endif
3021 
3022   TSAN_MAYBE_INTERCEPT__LWP_EXIT;
3023   TSAN_MAYBE_INTERCEPT_THR_EXIT;
3024 
3025 #if !SANITIZER_APPLE && !SANITIZER_ANDROID
3026   // Need to setup it, because interceptors check that the function is resolved.
3027   // But atexit is emitted directly into the module, so can't be resolved.
3028   REAL(atexit) = (int(*)(void(*)()))unreachable;
3029 #endif
3030 
3031   if (REAL(__cxa_atexit)(&finalize, 0, 0)) {
3032     Printf("ThreadSanitizer: failed to setup atexit callback\n");
3033     Die();
3034   }
3035   if (pthread_atfork(atfork_prepare, atfork_parent, atfork_child)) {
3036     Printf("ThreadSanitizer: failed to setup atfork callbacks\n");
3037     Die();
3038   }
3039 
3040 #if !SANITIZER_APPLE && !SANITIZER_NETBSD && !SANITIZER_FREEBSD
3041   if (pthread_key_create(&interceptor_ctx()->finalize_key, &thread_finalize)) {
3042     Printf("ThreadSanitizer: failed to create thread key\n");
3043     Die();
3044   }
3045 #endif
3046 
3047   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(cond_init);
3048   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(cond_destroy);
3049   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(cond_signal);
3050   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(cond_broadcast);
3051   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(cond_wait);
3052   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(mutex_init);
3053   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(mutex_destroy);
3054   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(mutex_lock);
3055   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(mutex_trylock);
3056   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(mutex_unlock);
3057   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(rwlock_init);
3058   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(rwlock_destroy);
3059   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(rwlock_rdlock);
3060   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(rwlock_tryrdlock);
3061   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(rwlock_wrlock);
3062   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(rwlock_trywrlock);
3063   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(rwlock_unlock);
3064   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(once);
3065   TSAN_MAYBE_INTERCEPT_FREEBSD_ALIAS(sigmask);
3066 
3067   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(cond_init);
3068   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(cond_signal);
3069   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(cond_broadcast);
3070   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(cond_wait);
3071   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(cond_destroy);
3072   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(mutex_init);
3073   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(mutex_destroy);
3074   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(mutex_lock);
3075   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(mutex_trylock);
3076   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(mutex_unlock);
3077   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(rwlock_init);
3078   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(rwlock_destroy);
3079   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(rwlock_rdlock);
3080   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(rwlock_tryrdlock);
3081   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(rwlock_wrlock);
3082   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(rwlock_trywrlock);
3083   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS(rwlock_unlock);
3084   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS_THR(once);
3085   TSAN_MAYBE_INTERCEPT_NETBSD_ALIAS_THR(sigsetmask);
3086 
3087   FdInit();
3088 }
3089 
3090 }  // namespace __tsan
3091 
3092 // Invisible barrier for tests.
3093 // There were several unsuccessful iterations for this functionality:
3094 // 1. Initially it was implemented in user code using
3095 //    REAL(pthread_barrier_wait). But pthread_barrier_wait is not supported on
3096 //    MacOS. Futexes are linux-specific for this matter.
3097 // 2. Then we switched to atomics+usleep(10). But usleep produced parasitic
3098 //    "as-if synchronized via sleep" messages in reports which failed some
3099 //    output tests.
3100 // 3. Then we switched to atomics+sched_yield. But this produced tons of tsan-
3101 //    visible events, which lead to "failed to restore stack trace" failures.
3102 // Note that no_sanitize_thread attribute does not turn off atomic interception
3103 // so attaching it to the function defined in user code does not help.
3104 // That's why we now have what we have.
3105 constexpr u32 kBarrierThreadBits = 10;
3106 constexpr u32 kBarrierThreads = 1 << kBarrierThreadBits;
3107 
3108 extern "C" {
3109 
3110 SANITIZER_INTERFACE_ATTRIBUTE void __tsan_testonly_barrier_init(
3111     atomic_uint32_t *barrier, u32 num_threads) {
3112   if (num_threads >= kBarrierThreads) {
3113     Printf("barrier_init: count is too large (%d)\n", num_threads);
3114     Die();
3115   }
3116   // kBarrierThreadBits lsb is thread count,
3117   // the remaining are count of entered threads.
3118   atomic_store(barrier, num_threads, memory_order_relaxed);
3119 }
3120 
3121 static u32 barrier_epoch(u32 value) {
3122   return (value >> kBarrierThreadBits) / (value & (kBarrierThreads - 1));
3123 }
3124 
3125 SANITIZER_INTERFACE_ATTRIBUTE void __tsan_testonly_barrier_wait(
3126     atomic_uint32_t *barrier) {
3127   u32 old = atomic_fetch_add(barrier, kBarrierThreads, memory_order_relaxed);
3128   u32 old_epoch = barrier_epoch(old);
3129   if (barrier_epoch(old + kBarrierThreads) != old_epoch) {
3130     FutexWake(barrier, (1 << 30));
3131     return;
3132   }
3133   for (;;) {
3134     u32 cur = atomic_load(barrier, memory_order_relaxed);
3135     if (barrier_epoch(cur) != old_epoch)
3136       return;
3137     FutexWait(barrier, cur);
3138   }
3139 }
3140 
3141 }  // extern "C"
3142