1 //===-- tsan_rtl_report.cc ------------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file is a part of ThreadSanitizer (TSan), a race detector.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "sanitizer_common/sanitizer_libc.h"
15 #include "sanitizer_common/sanitizer_placement_new.h"
16 #include "sanitizer_common/sanitizer_stackdepot.h"
17 #include "sanitizer_common/sanitizer_common.h"
18 #include "sanitizer_common/sanitizer_stacktrace.h"
19 #include "tsan_platform.h"
20 #include "tsan_rtl.h"
21 #include "tsan_suppressions.h"
22 #include "tsan_symbolize.h"
23 #include "tsan_report.h"
24 #include "tsan_sync.h"
25 #include "tsan_mman.h"
26 #include "tsan_flags.h"
27 #include "tsan_fd.h"
28
29 namespace __tsan {
30
31 using namespace __sanitizer; // NOLINT
32
33 static ReportStack *SymbolizeStack(StackTrace trace);
34
TsanCheckFailed(const char * file,int line,const char * cond,u64 v1,u64 v2)35 void TsanCheckFailed(const char *file, int line, const char *cond,
36 u64 v1, u64 v2) {
37 // There is high probability that interceptors will check-fail as well,
38 // on the other hand there is no sense in processing interceptors
39 // since we are going to die soon.
40 ScopedIgnoreInterceptors ignore;
41 Printf("FATAL: ThreadSanitizer CHECK failed: "
42 "%s:%d \"%s\" (0x%zx, 0x%zx)\n",
43 file, line, cond, (uptr)v1, (uptr)v2);
44 PrintCurrentStackSlow(StackTrace::GetCurrentPc());
45 Die();
46 }
47
48 // Can be overriden by an application/test to intercept reports.
49 #ifdef TSAN_EXTERNAL_HOOKS
50 bool OnReport(const ReportDesc *rep, bool suppressed);
51 #else
52 SANITIZER_WEAK_CXX_DEFAULT_IMPL
OnReport(const ReportDesc * rep,bool suppressed)53 bool OnReport(const ReportDesc *rep, bool suppressed) {
54 (void)rep;
55 return suppressed;
56 }
57 #endif
58
StackStripMain(SymbolizedStack * frames)59 static void StackStripMain(SymbolizedStack *frames) {
60 SymbolizedStack *last_frame = nullptr;
61 SymbolizedStack *last_frame2 = nullptr;
62 for (SymbolizedStack *cur = frames; cur; cur = cur->next) {
63 last_frame2 = last_frame;
64 last_frame = cur;
65 }
66
67 if (last_frame2 == 0)
68 return;
69 #ifndef SANITIZER_GO
70 const char *last = last_frame->info.function;
71 const char *last2 = last_frame2->info.function;
72 // Strip frame above 'main'
73 if (last2 && 0 == internal_strcmp(last2, "main")) {
74 last_frame->ClearAll();
75 last_frame2->next = nullptr;
76 // Strip our internal thread start routine.
77 } else if (last && 0 == internal_strcmp(last, "__tsan_thread_start_func")) {
78 last_frame->ClearAll();
79 last_frame2->next = nullptr;
80 // Strip global ctors init.
81 } else if (last && 0 == internal_strcmp(last, "__do_global_ctors_aux")) {
82 last_frame->ClearAll();
83 last_frame2->next = nullptr;
84 // If both are 0, then we probably just failed to symbolize.
85 } else if (last || last2) {
86 // Ensure that we recovered stack completely. Trimmed stack
87 // can actually happen if we do not instrument some code,
88 // so it's only a debug print. However we must try hard to not miss it
89 // due to our fault.
90 DPrintf("Bottom stack frame is missed\n");
91 }
92 #else
93 // The last frame always point into runtime (gosched0, goexit0, runtime.main).
94 last_frame->ClearAll();
95 last_frame2->next = nullptr;
96 #endif
97 }
98
SymbolizeStackId(u32 stack_id)99 ReportStack *SymbolizeStackId(u32 stack_id) {
100 if (stack_id == 0)
101 return 0;
102 StackTrace stack = StackDepotGet(stack_id);
103 if (stack.trace == nullptr)
104 return nullptr;
105 return SymbolizeStack(stack);
106 }
107
SymbolizeStack(StackTrace trace)108 static ReportStack *SymbolizeStack(StackTrace trace) {
109 if (trace.size == 0)
110 return 0;
111 SymbolizedStack *top = nullptr;
112 for (uptr si = 0; si < trace.size; si++) {
113 const uptr pc = trace.trace[si];
114 uptr pc1 = pc;
115 // We obtain the return address, but we're interested in the previous
116 // instruction.
117 if ((pc & kExternalPCBit) == 0)
118 pc1 = StackTrace::GetPreviousInstructionPc(pc);
119 SymbolizedStack *ent = SymbolizeCode(pc1);
120 CHECK_NE(ent, 0);
121 SymbolizedStack *last = ent;
122 while (last->next) {
123 last->info.address = pc; // restore original pc for report
124 last = last->next;
125 }
126 last->info.address = pc; // restore original pc for report
127 last->next = top;
128 top = ent;
129 }
130 StackStripMain(top);
131
132 ReportStack *stack = ReportStack::New();
133 stack->frames = top;
134 return stack;
135 }
136
ScopedReport(ReportType typ)137 ScopedReport::ScopedReport(ReportType typ) {
138 ctx->thread_registry->CheckLocked();
139 void *mem = internal_alloc(MBlockReport, sizeof(ReportDesc));
140 rep_ = new(mem) ReportDesc;
141 rep_->typ = typ;
142 ctx->report_mtx.Lock();
143 CommonSanitizerReportMutex.Lock();
144 }
145
~ScopedReport()146 ScopedReport::~ScopedReport() {
147 CommonSanitizerReportMutex.Unlock();
148 ctx->report_mtx.Unlock();
149 DestroyAndFree(rep_);
150 }
151
AddStack(StackTrace stack,bool suppressable)152 void ScopedReport::AddStack(StackTrace stack, bool suppressable) {
153 ReportStack **rs = rep_->stacks.PushBack();
154 *rs = SymbolizeStack(stack);
155 (*rs)->suppressable = suppressable;
156 }
157
AddMemoryAccess(uptr addr,Shadow s,StackTrace stack,const MutexSet * mset)158 void ScopedReport::AddMemoryAccess(uptr addr, Shadow s, StackTrace stack,
159 const MutexSet *mset) {
160 void *mem = internal_alloc(MBlockReportMop, sizeof(ReportMop));
161 ReportMop *mop = new(mem) ReportMop;
162 rep_->mops.PushBack(mop);
163 mop->tid = s.tid();
164 mop->addr = addr + s.addr0();
165 mop->size = s.size();
166 mop->write = s.IsWrite();
167 mop->atomic = s.IsAtomic();
168 mop->stack = SymbolizeStack(stack);
169 if (mop->stack)
170 mop->stack->suppressable = true;
171 for (uptr i = 0; i < mset->Size(); i++) {
172 MutexSet::Desc d = mset->Get(i);
173 u64 mid = this->AddMutex(d.id);
174 ReportMopMutex mtx = {mid, d.write};
175 mop->mset.PushBack(mtx);
176 }
177 }
178
AddUniqueTid(int unique_tid)179 void ScopedReport::AddUniqueTid(int unique_tid) {
180 rep_->unique_tids.PushBack(unique_tid);
181 }
182
AddThread(const ThreadContext * tctx,bool suppressable)183 void ScopedReport::AddThread(const ThreadContext *tctx, bool suppressable) {
184 for (uptr i = 0; i < rep_->threads.Size(); i++) {
185 if ((u32)rep_->threads[i]->id == tctx->tid)
186 return;
187 }
188 void *mem = internal_alloc(MBlockReportThread, sizeof(ReportThread));
189 ReportThread *rt = new(mem) ReportThread;
190 rep_->threads.PushBack(rt);
191 rt->id = tctx->tid;
192 rt->pid = tctx->os_id;
193 rt->running = (tctx->status == ThreadStatusRunning);
194 rt->name = internal_strdup(tctx->name);
195 rt->parent_tid = tctx->parent_tid;
196 rt->stack = 0;
197 rt->stack = SymbolizeStackId(tctx->creation_stack_id);
198 if (rt->stack)
199 rt->stack->suppressable = suppressable;
200 }
201
202 #ifndef SANITIZER_GO
FindThreadByUidLockedCallback(ThreadContextBase * tctx,void * arg)203 static bool FindThreadByUidLockedCallback(ThreadContextBase *tctx, void *arg) {
204 int unique_id = *(int *)arg;
205 return tctx->unique_id == (u32)unique_id;
206 }
207
FindThreadByUidLocked(int unique_id)208 static ThreadContext *FindThreadByUidLocked(int unique_id) {
209 ctx->thread_registry->CheckLocked();
210 return static_cast<ThreadContext *>(
211 ctx->thread_registry->FindThreadContextLocked(
212 FindThreadByUidLockedCallback, &unique_id));
213 }
214
FindThreadByTidLocked(int tid)215 static ThreadContext *FindThreadByTidLocked(int tid) {
216 ctx->thread_registry->CheckLocked();
217 return static_cast<ThreadContext*>(
218 ctx->thread_registry->GetThreadLocked(tid));
219 }
220
IsInStackOrTls(ThreadContextBase * tctx_base,void * arg)221 static bool IsInStackOrTls(ThreadContextBase *tctx_base, void *arg) {
222 uptr addr = (uptr)arg;
223 ThreadContext *tctx = static_cast<ThreadContext*>(tctx_base);
224 if (tctx->status != ThreadStatusRunning)
225 return false;
226 ThreadState *thr = tctx->thr;
227 CHECK(thr);
228 return ((addr >= thr->stk_addr && addr < thr->stk_addr + thr->stk_size) ||
229 (addr >= thr->tls_addr && addr < thr->tls_addr + thr->tls_size));
230 }
231
IsThreadStackOrTls(uptr addr,bool * is_stack)232 ThreadContext *IsThreadStackOrTls(uptr addr, bool *is_stack) {
233 ctx->thread_registry->CheckLocked();
234 ThreadContext *tctx = static_cast<ThreadContext*>(
235 ctx->thread_registry->FindThreadContextLocked(IsInStackOrTls,
236 (void*)addr));
237 if (!tctx)
238 return 0;
239 ThreadState *thr = tctx->thr;
240 CHECK(thr);
241 *is_stack = (addr >= thr->stk_addr && addr < thr->stk_addr + thr->stk_size);
242 return tctx;
243 }
244 #endif
245
AddThread(int unique_tid,bool suppressable)246 void ScopedReport::AddThread(int unique_tid, bool suppressable) {
247 #ifndef SANITIZER_GO
248 if (const ThreadContext *tctx = FindThreadByUidLocked(unique_tid))
249 AddThread(tctx, suppressable);
250 #endif
251 }
252
AddMutex(const SyncVar * s)253 void ScopedReport::AddMutex(const SyncVar *s) {
254 for (uptr i = 0; i < rep_->mutexes.Size(); i++) {
255 if (rep_->mutexes[i]->id == s->uid)
256 return;
257 }
258 void *mem = internal_alloc(MBlockReportMutex, sizeof(ReportMutex));
259 ReportMutex *rm = new(mem) ReportMutex;
260 rep_->mutexes.PushBack(rm);
261 rm->id = s->uid;
262 rm->addr = s->addr;
263 rm->destroyed = false;
264 rm->stack = SymbolizeStackId(s->creation_stack_id);
265 }
266
AddMutex(u64 id)267 u64 ScopedReport::AddMutex(u64 id) {
268 u64 uid = 0;
269 u64 mid = id;
270 uptr addr = SyncVar::SplitId(id, &uid);
271 SyncVar *s = ctx->metamap.GetIfExistsAndLock(addr);
272 // Check that the mutex is still alive.
273 // Another mutex can be created at the same address,
274 // so check uid as well.
275 if (s && s->CheckId(uid)) {
276 mid = s->uid;
277 AddMutex(s);
278 } else {
279 AddDeadMutex(id);
280 }
281 if (s)
282 s->mtx.Unlock();
283 return mid;
284 }
285
AddDeadMutex(u64 id)286 void ScopedReport::AddDeadMutex(u64 id) {
287 for (uptr i = 0; i < rep_->mutexes.Size(); i++) {
288 if (rep_->mutexes[i]->id == id)
289 return;
290 }
291 void *mem = internal_alloc(MBlockReportMutex, sizeof(ReportMutex));
292 ReportMutex *rm = new(mem) ReportMutex;
293 rep_->mutexes.PushBack(rm);
294 rm->id = id;
295 rm->addr = 0;
296 rm->destroyed = true;
297 rm->stack = 0;
298 }
299
AddLocation(uptr addr,uptr size)300 void ScopedReport::AddLocation(uptr addr, uptr size) {
301 if (addr == 0)
302 return;
303 #ifndef SANITIZER_GO
304 int fd = -1;
305 int creat_tid = -1;
306 u32 creat_stack = 0;
307 if (FdLocation(addr, &fd, &creat_tid, &creat_stack)) {
308 ReportLocation *loc = ReportLocation::New(ReportLocationFD);
309 loc->fd = fd;
310 loc->tid = creat_tid;
311 loc->stack = SymbolizeStackId(creat_stack);
312 rep_->locs.PushBack(loc);
313 ThreadContext *tctx = FindThreadByUidLocked(creat_tid);
314 if (tctx)
315 AddThread(tctx);
316 return;
317 }
318 MBlock *b = 0;
319 Allocator *a = allocator();
320 if (a->PointerIsMine((void*)addr)) {
321 void *block_begin = a->GetBlockBegin((void*)addr);
322 if (block_begin)
323 b = ctx->metamap.GetBlock((uptr)block_begin);
324 }
325 if (b != 0) {
326 ThreadContext *tctx = FindThreadByTidLocked(b->tid);
327 ReportLocation *loc = ReportLocation::New(ReportLocationHeap);
328 loc->heap_chunk_start = (uptr)allocator()->GetBlockBegin((void *)addr);
329 loc->heap_chunk_size = b->siz;
330 loc->tid = tctx ? tctx->tid : b->tid;
331 loc->stack = SymbolizeStackId(b->stk);
332 rep_->locs.PushBack(loc);
333 if (tctx)
334 AddThread(tctx);
335 return;
336 }
337 bool is_stack = false;
338 if (ThreadContext *tctx = IsThreadStackOrTls(addr, &is_stack)) {
339 ReportLocation *loc =
340 ReportLocation::New(is_stack ? ReportLocationStack : ReportLocationTLS);
341 loc->tid = tctx->tid;
342 rep_->locs.PushBack(loc);
343 AddThread(tctx);
344 }
345 if (ReportLocation *loc = SymbolizeData(addr)) {
346 loc->suppressable = true;
347 rep_->locs.PushBack(loc);
348 return;
349 }
350 #endif
351 }
352
353 #ifndef SANITIZER_GO
AddSleep(u32 stack_id)354 void ScopedReport::AddSleep(u32 stack_id) {
355 rep_->sleep = SymbolizeStackId(stack_id);
356 }
357 #endif
358
SetCount(int count)359 void ScopedReport::SetCount(int count) {
360 rep_->count = count;
361 }
362
GetReport() const363 const ReportDesc *ScopedReport::GetReport() const {
364 return rep_;
365 }
366
RestoreStack(int tid,const u64 epoch,VarSizeStackTrace * stk,MutexSet * mset)367 void RestoreStack(int tid, const u64 epoch, VarSizeStackTrace *stk,
368 MutexSet *mset) {
369 // This function restores stack trace and mutex set for the thread/epoch.
370 // It does so by getting stack trace and mutex set at the beginning of
371 // trace part, and then replaying the trace till the given epoch.
372 Trace* trace = ThreadTrace(tid);
373 ReadLock l(&trace->mtx);
374 const int partidx = (epoch / kTracePartSize) % TraceParts();
375 TraceHeader* hdr = &trace->headers[partidx];
376 if (epoch < hdr->epoch0 || epoch >= hdr->epoch0 + kTracePartSize)
377 return;
378 CHECK_EQ(RoundDown(epoch, kTracePartSize), hdr->epoch0);
379 const u64 epoch0 = RoundDown(epoch, TraceSize());
380 const u64 eend = epoch % TraceSize();
381 const u64 ebegin = RoundDown(eend, kTracePartSize);
382 DPrintf("#%d: RestoreStack epoch=%zu ebegin=%zu eend=%zu partidx=%d\n",
383 tid, (uptr)epoch, (uptr)ebegin, (uptr)eend, partidx);
384 Vector<uptr> stack(MBlockReportStack);
385 stack.Resize(hdr->stack0.size + 64);
386 for (uptr i = 0; i < hdr->stack0.size; i++) {
387 stack[i] = hdr->stack0.trace[i];
388 DPrintf2(" #%02zu: pc=%zx\n", i, stack[i]);
389 }
390 if (mset)
391 *mset = hdr->mset0;
392 uptr pos = hdr->stack0.size;
393 Event *events = (Event*)GetThreadTrace(tid);
394 for (uptr i = ebegin; i <= eend; i++) {
395 Event ev = events[i];
396 EventType typ = (EventType)(ev >> 61);
397 uptr pc = (uptr)(ev & ((1ull << 61) - 1));
398 DPrintf2(" %zu typ=%d pc=%zx\n", i, typ, pc);
399 if (typ == EventTypeMop) {
400 stack[pos] = pc;
401 } else if (typ == EventTypeFuncEnter) {
402 if (stack.Size() < pos + 2)
403 stack.Resize(pos + 2);
404 stack[pos++] = pc;
405 } else if (typ == EventTypeFuncExit) {
406 if (pos > 0)
407 pos--;
408 }
409 if (mset) {
410 if (typ == EventTypeLock) {
411 mset->Add(pc, true, epoch0 + i);
412 } else if (typ == EventTypeUnlock) {
413 mset->Del(pc, true);
414 } else if (typ == EventTypeRLock) {
415 mset->Add(pc, false, epoch0 + i);
416 } else if (typ == EventTypeRUnlock) {
417 mset->Del(pc, false);
418 }
419 }
420 for (uptr j = 0; j <= pos; j++)
421 DPrintf2(" #%zu: %zx\n", j, stack[j]);
422 }
423 if (pos == 0 && stack[0] == 0)
424 return;
425 pos++;
426 stk->Init(&stack[0], pos);
427 }
428
HandleRacyStacks(ThreadState * thr,VarSizeStackTrace traces[2],uptr addr_min,uptr addr_max)429 static bool HandleRacyStacks(ThreadState *thr, VarSizeStackTrace traces[2],
430 uptr addr_min, uptr addr_max) {
431 bool equal_stack = false;
432 RacyStacks hash;
433 bool equal_address = false;
434 RacyAddress ra0 = {addr_min, addr_max};
435 {
436 ReadLock lock(&ctx->racy_mtx);
437 if (flags()->suppress_equal_stacks) {
438 hash.hash[0] = md5_hash(traces[0].trace, traces[0].size * sizeof(uptr));
439 hash.hash[1] = md5_hash(traces[1].trace, traces[1].size * sizeof(uptr));
440 for (uptr i = 0; i < ctx->racy_stacks.Size(); i++) {
441 if (hash == ctx->racy_stacks[i]) {
442 VPrintf(2,
443 "ThreadSanitizer: suppressing report as doubled (stack)\n");
444 equal_stack = true;
445 break;
446 }
447 }
448 }
449 if (flags()->suppress_equal_addresses) {
450 for (uptr i = 0; i < ctx->racy_addresses.Size(); i++) {
451 RacyAddress ra2 = ctx->racy_addresses[i];
452 uptr maxbeg = max(ra0.addr_min, ra2.addr_min);
453 uptr minend = min(ra0.addr_max, ra2.addr_max);
454 if (maxbeg < minend) {
455 VPrintf(2, "ThreadSanitizer: suppressing report as doubled (addr)\n");
456 equal_address = true;
457 break;
458 }
459 }
460 }
461 }
462 if (!equal_stack && !equal_address)
463 return false;
464 if (!equal_stack) {
465 Lock lock(&ctx->racy_mtx);
466 ctx->racy_stacks.PushBack(hash);
467 }
468 if (!equal_address) {
469 Lock lock(&ctx->racy_mtx);
470 ctx->racy_addresses.PushBack(ra0);
471 }
472 return true;
473 }
474
AddRacyStacks(ThreadState * thr,VarSizeStackTrace traces[2],uptr addr_min,uptr addr_max)475 static void AddRacyStacks(ThreadState *thr, VarSizeStackTrace traces[2],
476 uptr addr_min, uptr addr_max) {
477 Lock lock(&ctx->racy_mtx);
478 if (flags()->suppress_equal_stacks) {
479 RacyStacks hash;
480 hash.hash[0] = md5_hash(traces[0].trace, traces[0].size * sizeof(uptr));
481 hash.hash[1] = md5_hash(traces[1].trace, traces[1].size * sizeof(uptr));
482 ctx->racy_stacks.PushBack(hash);
483 }
484 if (flags()->suppress_equal_addresses) {
485 RacyAddress ra0 = {addr_min, addr_max};
486 ctx->racy_addresses.PushBack(ra0);
487 }
488 }
489
OutputReport(ThreadState * thr,const ScopedReport & srep)490 bool OutputReport(ThreadState *thr, const ScopedReport &srep) {
491 if (!flags()->report_bugs)
492 return false;
493 atomic_store_relaxed(&ctx->last_symbolize_time_ns, NanoTime());
494 const ReportDesc *rep = srep.GetReport();
495 Suppression *supp = 0;
496 uptr pc_or_addr = 0;
497 for (uptr i = 0; pc_or_addr == 0 && i < rep->mops.Size(); i++)
498 pc_or_addr = IsSuppressed(rep->typ, rep->mops[i]->stack, &supp);
499 for (uptr i = 0; pc_or_addr == 0 && i < rep->stacks.Size(); i++)
500 pc_or_addr = IsSuppressed(rep->typ, rep->stacks[i], &supp);
501 for (uptr i = 0; pc_or_addr == 0 && i < rep->threads.Size(); i++)
502 pc_or_addr = IsSuppressed(rep->typ, rep->threads[i]->stack, &supp);
503 for (uptr i = 0; pc_or_addr == 0 && i < rep->locs.Size(); i++)
504 pc_or_addr = IsSuppressed(rep->typ, rep->locs[i], &supp);
505 if (pc_or_addr != 0) {
506 Lock lock(&ctx->fired_suppressions_mtx);
507 FiredSuppression s = {srep.GetReport()->typ, pc_or_addr, supp};
508 ctx->fired_suppressions.push_back(s);
509 }
510 {
511 bool old_is_freeing = thr->is_freeing;
512 thr->is_freeing = false;
513 bool suppressed = OnReport(rep, pc_or_addr != 0);
514 thr->is_freeing = old_is_freeing;
515 if (suppressed)
516 return false;
517 }
518 PrintReport(rep);
519 ctx->nreported++;
520 if (flags()->halt_on_error)
521 Die();
522 return true;
523 }
524
IsFiredSuppression(Context * ctx,ReportType type,StackTrace trace)525 bool IsFiredSuppression(Context *ctx, ReportType type, StackTrace trace) {
526 ReadLock lock(&ctx->fired_suppressions_mtx);
527 for (uptr k = 0; k < ctx->fired_suppressions.size(); k++) {
528 if (ctx->fired_suppressions[k].type != type)
529 continue;
530 for (uptr j = 0; j < trace.size; j++) {
531 FiredSuppression *s = &ctx->fired_suppressions[k];
532 if (trace.trace[j] == s->pc_or_addr) {
533 if (s->supp)
534 atomic_fetch_add(&s->supp->hit_count, 1, memory_order_relaxed);
535 return true;
536 }
537 }
538 }
539 return false;
540 }
541
IsFiredSuppression(Context * ctx,ReportType type,uptr addr)542 static bool IsFiredSuppression(Context *ctx, ReportType type, uptr addr) {
543 ReadLock lock(&ctx->fired_suppressions_mtx);
544 for (uptr k = 0; k < ctx->fired_suppressions.size(); k++) {
545 if (ctx->fired_suppressions[k].type != type)
546 continue;
547 FiredSuppression *s = &ctx->fired_suppressions[k];
548 if (addr == s->pc_or_addr) {
549 if (s->supp)
550 atomic_fetch_add(&s->supp->hit_count, 1, memory_order_relaxed);
551 return true;
552 }
553 }
554 return false;
555 }
556
RaceBetweenAtomicAndFree(ThreadState * thr)557 static bool RaceBetweenAtomicAndFree(ThreadState *thr) {
558 Shadow s0(thr->racy_state[0]);
559 Shadow s1(thr->racy_state[1]);
560 CHECK(!(s0.IsAtomic() && s1.IsAtomic()));
561 if (!s0.IsAtomic() && !s1.IsAtomic())
562 return true;
563 if (s0.IsAtomic() && s1.IsFreed())
564 return true;
565 if (s1.IsAtomic() && thr->is_freeing)
566 return true;
567 return false;
568 }
569
ReportRace(ThreadState * thr)570 void ReportRace(ThreadState *thr) {
571 CheckNoLocks(thr);
572
573 // Symbolizer makes lots of intercepted calls. If we try to process them,
574 // at best it will cause deadlocks on internal mutexes.
575 ScopedIgnoreInterceptors ignore;
576
577 if (!flags()->report_bugs)
578 return;
579 if (!flags()->report_atomic_races && !RaceBetweenAtomicAndFree(thr))
580 return;
581
582 bool freed = false;
583 {
584 Shadow s(thr->racy_state[1]);
585 freed = s.GetFreedAndReset();
586 thr->racy_state[1] = s.raw();
587 }
588
589 uptr addr = ShadowToMem((uptr)thr->racy_shadow_addr);
590 uptr addr_min = 0;
591 uptr addr_max = 0;
592 {
593 uptr a0 = addr + Shadow(thr->racy_state[0]).addr0();
594 uptr a1 = addr + Shadow(thr->racy_state[1]).addr0();
595 uptr e0 = a0 + Shadow(thr->racy_state[0]).size();
596 uptr e1 = a1 + Shadow(thr->racy_state[1]).size();
597 addr_min = min(a0, a1);
598 addr_max = max(e0, e1);
599 if (IsExpectedReport(addr_min, addr_max - addr_min))
600 return;
601 }
602
603 ReportType typ = ReportTypeRace;
604 if (thr->is_vptr_access && freed)
605 typ = ReportTypeVptrUseAfterFree;
606 else if (thr->is_vptr_access)
607 typ = ReportTypeVptrRace;
608 else if (freed)
609 typ = ReportTypeUseAfterFree;
610
611 if (IsFiredSuppression(ctx, typ, addr))
612 return;
613
614 const uptr kMop = 2;
615 VarSizeStackTrace traces[kMop];
616 const uptr toppc = TraceTopPC(thr);
617 ObtainCurrentStack(thr, toppc, &traces[0]);
618 if (IsFiredSuppression(ctx, typ, traces[0]))
619 return;
620
621 // MutexSet is too large to live on stack.
622 Vector<u64> mset_buffer(MBlockScopedBuf);
623 mset_buffer.Resize(sizeof(MutexSet) / sizeof(u64) + 1);
624 MutexSet *mset2 = new(&mset_buffer[0]) MutexSet();
625
626 Shadow s2(thr->racy_state[1]);
627 RestoreStack(s2.tid(), s2.epoch(), &traces[1], mset2);
628 if (IsFiredSuppression(ctx, typ, traces[1]))
629 return;
630
631 if (HandleRacyStacks(thr, traces, addr_min, addr_max))
632 return;
633
634 ThreadRegistryLock l0(ctx->thread_registry);
635 ScopedReport rep(typ);
636 for (uptr i = 0; i < kMop; i++) {
637 Shadow s(thr->racy_state[i]);
638 rep.AddMemoryAccess(addr, s, traces[i], i == 0 ? &thr->mset : mset2);
639 }
640
641 for (uptr i = 0; i < kMop; i++) {
642 FastState s(thr->racy_state[i]);
643 ThreadContext *tctx = static_cast<ThreadContext*>(
644 ctx->thread_registry->GetThreadLocked(s.tid()));
645 if (s.epoch() < tctx->epoch0 || s.epoch() > tctx->epoch1)
646 continue;
647 rep.AddThread(tctx);
648 }
649
650 rep.AddLocation(addr_min, addr_max - addr_min);
651
652 #ifndef SANITIZER_GO
653 { // NOLINT
654 Shadow s(thr->racy_state[1]);
655 if (s.epoch() <= thr->last_sleep_clock.get(s.tid()))
656 rep.AddSleep(thr->last_sleep_stack_id);
657 }
658 #endif
659
660 if (!OutputReport(thr, rep))
661 return;
662
663 AddRacyStacks(thr, traces, addr_min, addr_max);
664 }
665
PrintCurrentStack(ThreadState * thr,uptr pc)666 void PrintCurrentStack(ThreadState *thr, uptr pc) {
667 VarSizeStackTrace trace;
668 ObtainCurrentStack(thr, pc, &trace);
669 PrintStack(SymbolizeStack(trace));
670 }
671
PrintCurrentStackSlow(uptr pc)672 void PrintCurrentStackSlow(uptr pc) {
673 #ifndef SANITIZER_GO
674 BufferedStackTrace *ptrace =
675 new(internal_alloc(MBlockStackTrace, sizeof(BufferedStackTrace)))
676 BufferedStackTrace();
677 ptrace->Unwind(kStackTraceMax, pc, 0, 0, 0, 0, false);
678 for (uptr i = 0; i < ptrace->size / 2; i++) {
679 uptr tmp = ptrace->trace_buffer[i];
680 ptrace->trace_buffer[i] = ptrace->trace_buffer[ptrace->size - i - 1];
681 ptrace->trace_buffer[ptrace->size - i - 1] = tmp;
682 }
683 PrintStack(SymbolizeStack(*ptrace));
684 #endif
685 }
686
687 } // namespace __tsan
688
689 using namespace __tsan;
690
691 extern "C" {
692 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_print_stack_trace()693 void __sanitizer_print_stack_trace() {
694 PrintCurrentStackSlow(StackTrace::GetCurrentPc());
695 }
696 } // extern "C"
697