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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(const 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   ScopedInRtl in_rtl;
38   Printf("FATAL: ThreadSanitizer CHECK failed: "
39          "%s:%d \"%s\" (0x%zx, 0x%zx)\n",
40          file, line, cond, (uptr)v1, (uptr)v2);
41   PrintCurrentStackSlow();
42   Die();
43 }
44 
45 // Can be overriden by an application/test to intercept reports.
46 #ifdef TSAN_EXTERNAL_HOOKS
47 bool OnReport(const ReportDesc *rep, bool suppressed);
48 #else
49 SANITIZER_INTERFACE_ATTRIBUTE
OnReport(const ReportDesc * rep,bool suppressed)50 bool WEAK OnReport(const ReportDesc *rep, bool suppressed) {
51   (void)rep;
52   return suppressed;
53 }
54 #endif
55 
StackStripMain(ReportStack * stack)56 static void StackStripMain(ReportStack *stack) {
57   ReportStack *last_frame = 0;
58   ReportStack *last_frame2 = 0;
59   const char *prefix = "__interceptor_";
60   uptr prefix_len = internal_strlen(prefix);
61   const char *path_prefix = flags()->strip_path_prefix;
62   uptr path_prefix_len = internal_strlen(path_prefix);
63   char *pos;
64   for (ReportStack *ent = stack; ent; ent = ent->next) {
65     if (ent->func && 0 == internal_strncmp(ent->func, prefix, prefix_len))
66       ent->func += prefix_len;
67     if (ent->file && (pos = internal_strstr(ent->file, path_prefix)))
68       ent->file = pos + path_prefix_len;
69     if (ent->file && ent->file[0] == '.' && ent->file[1] == '/')
70       ent->file += 2;
71     last_frame2 = last_frame;
72     last_frame = ent;
73   }
74 
75   if (last_frame2 == 0)
76     return;
77   const char *last = last_frame->func;
78 #ifndef TSAN_GO
79   const char *last2 = last_frame2->func;
80   // Strip frame above 'main'
81   if (last2 && 0 == internal_strcmp(last2, "main")) {
82     last_frame2->next = 0;
83   // Strip our internal thread start routine.
84   } else if (last && 0 == internal_strcmp(last, "__tsan_thread_start_func")) {
85     last_frame2->next = 0;
86   // Strip global ctors init.
87   } else if (last && 0 == internal_strcmp(last, "__do_global_ctors_aux")) {
88     last_frame2->next = 0;
89   // If both are 0, then we probably just failed to symbolize.
90   } else if (last || last2) {
91     // Ensure that we recovered stack completely. Trimmed stack
92     // can actually happen if we do not instrument some code,
93     // so it's only a debug print. However we must try hard to not miss it
94     // due to our fault.
95     DPrintf("Bottom stack frame of stack %zx is missed\n", stack->pc);
96   }
97 #else
98   // The last frame always point into runtime (gosched0, goexit0, runtime.main).
99   last_frame2->next = 0;
100   (void)last;
101 #endif
102 }
103 
SymbolizeStack(const StackTrace & trace)104 static ReportStack *SymbolizeStack(const StackTrace& trace) {
105   if (trace.IsEmpty())
106     return 0;
107   ReportStack *stack = 0;
108   for (uptr si = 0; si < trace.Size(); si++) {
109     const uptr pc = trace.Get(si);
110 #ifndef TSAN_GO
111     // We obtain the return address, that is, address of the next instruction,
112     // so offset it by 1 byte.
113     const uptr pc1 = __sanitizer::StackTrace::GetPreviousInstructionPc(pc);
114 #else
115     // FIXME(dvyukov): Go sometimes uses address of a function as top pc.
116     uptr pc1 = pc;
117     if (si != trace.Size() - 1)
118       pc1 -= 1;
119 #endif
120     ReportStack *ent = SymbolizeCode(pc1);
121     CHECK_NE(ent, 0);
122     ReportStack *last = ent;
123     while (last->next) {
124       last->pc = pc;  // restore original pc for report
125       last = last->next;
126     }
127     last->pc = pc;  // restore original pc for report
128     last->next = stack;
129     stack = ent;
130   }
131   StackStripMain(stack);
132   return stack;
133 }
134 
ScopedReport(ReportType typ)135 ScopedReport::ScopedReport(ReportType typ) {
136   ctx_ = CTX();
137   ctx_->thread_registry->CheckLocked();
138   void *mem = internal_alloc(MBlockReport, sizeof(ReportDesc));
139   rep_ = new(mem) ReportDesc;
140   rep_->typ = typ;
141   ctx_->report_mtx.Lock();
142   CommonSanitizerReportMutex.Lock();
143 }
144 
~ScopedReport()145 ScopedReport::~ScopedReport() {
146   CommonSanitizerReportMutex.Unlock();
147   ctx_->report_mtx.Unlock();
148   DestroyAndFree(rep_);
149 }
150 
AddStack(const StackTrace * stack)151 void ScopedReport::AddStack(const StackTrace *stack) {
152   ReportStack **rs = rep_->stacks.PushBack();
153   *rs = SymbolizeStack(*stack);
154 }
155 
AddMemoryAccess(uptr addr,Shadow s,const StackTrace * stack,const MutexSet * mset)156 void ScopedReport::AddMemoryAccess(uptr addr, Shadow s,
157     const StackTrace *stack, const MutexSet *mset) {
158   void *mem = internal_alloc(MBlockReportMop, sizeof(ReportMop));
159   ReportMop *mop = new(mem) ReportMop;
160   rep_->mops.PushBack(mop);
161   mop->tid = s.tid();
162   mop->addr = addr + s.addr0();
163   mop->size = s.size();
164   mop->write = s.IsWrite();
165   mop->atomic = s.IsAtomic();
166   mop->stack = SymbolizeStack(*stack);
167   for (uptr i = 0; i < mset->Size(); i++) {
168     MutexSet::Desc d = mset->Get(i);
169     u64 uid = 0;
170     uptr addr = SyncVar::SplitId(d.id, &uid);
171     SyncVar *s = ctx_->synctab.GetIfExistsAndLock(addr, false);
172     // Check that the mutex is still alive.
173     // Another mutex can be created at the same address,
174     // so check uid as well.
175     if (s && s->CheckId(uid)) {
176       ReportMopMutex mtx = {s->uid, d.write};
177       mop->mset.PushBack(mtx);
178       AddMutex(s);
179     } else {
180       ReportMopMutex mtx = {d.id, d.write};
181       mop->mset.PushBack(mtx);
182       AddMutex(d.id);
183     }
184     if (s)
185       s->mtx.ReadUnlock();
186   }
187 }
188 
AddThread(const ThreadContext * tctx)189 void ScopedReport::AddThread(const ThreadContext *tctx) {
190   for (uptr i = 0; i < rep_->threads.Size(); i++) {
191     if ((u32)rep_->threads[i]->id == tctx->tid)
192       return;
193   }
194   void *mem = internal_alloc(MBlockReportThread, sizeof(ReportThread));
195   ReportThread *rt = new(mem) ReportThread();
196   rep_->threads.PushBack(rt);
197   rt->id = tctx->tid;
198   rt->pid = tctx->os_id;
199   rt->running = (tctx->status == ThreadStatusRunning);
200   rt->name = tctx->name ? internal_strdup(tctx->name) : 0;
201   rt->parent_tid = tctx->parent_tid;
202   rt->stack = 0;
203 #ifdef TSAN_GO
204   rt->stack = SymbolizeStack(tctx->creation_stack);
205 #else
206   uptr ssz = 0;
207   const uptr *stack = StackDepotGet(tctx->creation_stack_id, &ssz);
208   if (stack) {
209     StackTrace trace;
210     trace.Init(stack, ssz);
211     rt->stack = SymbolizeStack(trace);
212   }
213 #endif
214 }
215 
216 #ifndef TSAN_GO
FindThreadByUidLocked(int unique_id)217 static ThreadContext *FindThreadByUidLocked(int unique_id) {
218   Context *ctx = CTX();
219   ctx->thread_registry->CheckLocked();
220   for (unsigned i = 0; i < kMaxTid; i++) {
221     ThreadContext *tctx = static_cast<ThreadContext*>(
222         ctx->thread_registry->GetThreadLocked(i));
223     if (tctx && tctx->unique_id == (u32)unique_id) {
224       return tctx;
225     }
226   }
227   return 0;
228 }
229 
FindThreadByTidLocked(int tid)230 static ThreadContext *FindThreadByTidLocked(int tid) {
231   Context *ctx = CTX();
232   ctx->thread_registry->CheckLocked();
233   return static_cast<ThreadContext*>(
234       ctx->thread_registry->GetThreadLocked(tid));
235 }
236 
IsInStackOrTls(ThreadContextBase * tctx_base,void * arg)237 static bool IsInStackOrTls(ThreadContextBase *tctx_base, void *arg) {
238   uptr addr = (uptr)arg;
239   ThreadContext *tctx = static_cast<ThreadContext*>(tctx_base);
240   if (tctx->status != ThreadStatusRunning)
241     return false;
242   ThreadState *thr = tctx->thr;
243   CHECK(thr);
244   return ((addr >= thr->stk_addr && addr < thr->stk_addr + thr->stk_size) ||
245           (addr >= thr->tls_addr && addr < thr->tls_addr + thr->tls_size));
246 }
247 
IsThreadStackOrTls(uptr addr,bool * is_stack)248 ThreadContext *IsThreadStackOrTls(uptr addr, bool *is_stack) {
249   Context *ctx = CTX();
250   ctx->thread_registry->CheckLocked();
251   ThreadContext *tctx = static_cast<ThreadContext*>(
252       ctx->thread_registry->FindThreadContextLocked(IsInStackOrTls,
253                                                     (void*)addr));
254   if (!tctx)
255     return 0;
256   ThreadState *thr = tctx->thr;
257   CHECK(thr);
258   *is_stack = (addr >= thr->stk_addr && addr < thr->stk_addr + thr->stk_size);
259   return tctx;
260 }
261 #endif
262 
AddMutex(const SyncVar * s)263 void ScopedReport::AddMutex(const SyncVar *s) {
264   for (uptr i = 0; i < rep_->mutexes.Size(); i++) {
265     if (rep_->mutexes[i]->id == s->uid)
266       return;
267   }
268   void *mem = internal_alloc(MBlockReportMutex, sizeof(ReportMutex));
269   ReportMutex *rm = new(mem) ReportMutex();
270   rep_->mutexes.PushBack(rm);
271   rm->id = s->uid;
272   rm->destroyed = false;
273   rm->stack = 0;
274 #ifndef TSAN_GO
275   uptr ssz = 0;
276   const uptr *stack = StackDepotGet(s->creation_stack_id, &ssz);
277   if (stack) {
278     StackTrace trace;
279     trace.Init(stack, ssz);
280     rm->stack = SymbolizeStack(trace);
281   }
282 #endif
283 }
284 
AddMutex(u64 id)285 void ScopedReport::AddMutex(u64 id) {
286   for (uptr i = 0; i < rep_->mutexes.Size(); i++) {
287     if (rep_->mutexes[i]->id == id)
288       return;
289   }
290   void *mem = internal_alloc(MBlockReportMutex, sizeof(ReportMutex));
291   ReportMutex *rm = new(mem) ReportMutex();
292   rep_->mutexes.PushBack(rm);
293   rm->id = id;
294   rm->destroyed = true;
295   rm->stack = 0;
296 }
297 
AddLocation(uptr addr,uptr size)298 void ScopedReport::AddLocation(uptr addr, uptr size) {
299   if (addr == 0)
300     return;
301 #ifndef TSAN_GO
302   int fd = -1;
303   int creat_tid = -1;
304   u32 creat_stack = 0;
305   if (FdLocation(addr, &fd, &creat_tid, &creat_stack)
306       || FdLocation(AlternativeAddress(addr), &fd, &creat_tid, &creat_stack)) {
307     void *mem = internal_alloc(MBlockReportLoc, sizeof(ReportLocation));
308     ReportLocation *loc = new(mem) ReportLocation();
309     rep_->locs.PushBack(loc);
310     loc->type = ReportLocationFD;
311     loc->fd = fd;
312     loc->tid = creat_tid;
313     uptr ssz = 0;
314     const uptr *stack = StackDepotGet(creat_stack, &ssz);
315     if (stack) {
316       StackTrace trace;
317       trace.Init(stack, ssz);
318       loc->stack = SymbolizeStack(trace);
319     }
320     ThreadContext *tctx = FindThreadByUidLocked(creat_tid);
321     if (tctx)
322       AddThread(tctx);
323     return;
324   }
325   MBlock *b = 0;
326   if (allocator()->PointerIsMine((void*)addr)
327       && (b = user_mblock(0, (void*)addr))) {
328     ThreadContext *tctx = FindThreadByTidLocked(b->Tid());
329     void *mem = internal_alloc(MBlockReportLoc, sizeof(ReportLocation));
330     ReportLocation *loc = new(mem) ReportLocation();
331     rep_->locs.PushBack(loc);
332     loc->type = ReportLocationHeap;
333     loc->addr = (uptr)allocator()->GetBlockBegin((void*)addr);
334     loc->size = b->Size();
335     loc->tid = tctx ? tctx->tid : b->Tid();
336     loc->name = 0;
337     loc->file = 0;
338     loc->line = 0;
339     loc->stack = 0;
340     uptr ssz = 0;
341     const uptr *stack = StackDepotGet(b->StackId(), &ssz);
342     if (stack) {
343       StackTrace trace;
344       trace.Init(stack, ssz);
345       loc->stack = SymbolizeStack(trace);
346     }
347     if (tctx)
348       AddThread(tctx);
349     return;
350   }
351   bool is_stack = false;
352   if (ThreadContext *tctx = IsThreadStackOrTls(addr, &is_stack)) {
353     void *mem = internal_alloc(MBlockReportLoc, sizeof(ReportLocation));
354     ReportLocation *loc = new(mem) ReportLocation();
355     rep_->locs.PushBack(loc);
356     loc->type = is_stack ? ReportLocationStack : ReportLocationTLS;
357     loc->tid = tctx->tid;
358     AddThread(tctx);
359   }
360   ReportLocation *loc = SymbolizeData(addr);
361   if (loc) {
362     rep_->locs.PushBack(loc);
363     return;
364   }
365 #endif
366 }
367 
368 #ifndef TSAN_GO
AddSleep(u32 stack_id)369 void ScopedReport::AddSleep(u32 stack_id) {
370   uptr ssz = 0;
371   const uptr *stack = StackDepotGet(stack_id, &ssz);
372   if (stack) {
373     StackTrace trace;
374     trace.Init(stack, ssz);
375     rep_->sleep = SymbolizeStack(trace);
376   }
377 }
378 #endif
379 
SetCount(int count)380 void ScopedReport::SetCount(int count) {
381   rep_->count = count;
382 }
383 
GetReport() const384 const ReportDesc *ScopedReport::GetReport() const {
385   return rep_;
386 }
387 
RestoreStack(int tid,const u64 epoch,StackTrace * stk,MutexSet * mset)388 void RestoreStack(int tid, const u64 epoch, StackTrace *stk, MutexSet *mset) {
389   // This function restores stack trace and mutex set for the thread/epoch.
390   // It does so by getting stack trace and mutex set at the beginning of
391   // trace part, and then replaying the trace till the given epoch.
392   Context *ctx = CTX();
393   ctx->thread_registry->CheckLocked();
394   ThreadContext *tctx = static_cast<ThreadContext*>(
395       ctx->thread_registry->GetThreadLocked(tid));
396   if (tctx == 0)
397     return;
398   if (tctx->status != ThreadStatusRunning
399       && tctx->status != ThreadStatusFinished
400       && tctx->status != ThreadStatusDead)
401     return;
402   Trace* trace = ThreadTrace(tctx->tid);
403   Lock l(&trace->mtx);
404   const int partidx = (epoch / kTracePartSize) % TraceParts();
405   TraceHeader* hdr = &trace->headers[partidx];
406   if (epoch < hdr->epoch0)
407     return;
408   const u64 epoch0 = RoundDown(epoch, TraceSize());
409   const u64 eend = epoch % TraceSize();
410   const u64 ebegin = RoundDown(eend, kTracePartSize);
411   DPrintf("#%d: RestoreStack epoch=%zu ebegin=%zu eend=%zu partidx=%d\n",
412           tid, (uptr)epoch, (uptr)ebegin, (uptr)eend, partidx);
413   InternalScopedBuffer<uptr> stack(1024);  // FIXME: de-hardcode 1024
414   for (uptr i = 0; i < hdr->stack0.Size(); i++) {
415     stack[i] = hdr->stack0.Get(i);
416     DPrintf2("  #%02lu: pc=%zx\n", i, stack[i]);
417   }
418   if (mset)
419     *mset = hdr->mset0;
420   uptr pos = hdr->stack0.Size();
421   Event *events = (Event*)GetThreadTrace(tid);
422   for (uptr i = ebegin; i <= eend; i++) {
423     Event ev = events[i];
424     EventType typ = (EventType)(ev >> 61);
425     uptr pc = (uptr)(ev & ((1ull << 61) - 1));
426     DPrintf2("  %zu typ=%d pc=%zx\n", i, typ, pc);
427     if (typ == EventTypeMop) {
428       stack[pos] = pc;
429     } else if (typ == EventTypeFuncEnter) {
430       stack[pos++] = pc;
431     } else if (typ == EventTypeFuncExit) {
432       if (pos > 0)
433         pos--;
434     }
435     if (mset) {
436       if (typ == EventTypeLock) {
437         mset->Add(pc, true, epoch0 + i);
438       } else if (typ == EventTypeUnlock) {
439         mset->Del(pc, true);
440       } else if (typ == EventTypeRLock) {
441         mset->Add(pc, false, epoch0 + i);
442       } else if (typ == EventTypeRUnlock) {
443         mset->Del(pc, false);
444       }
445     }
446     for (uptr j = 0; j <= pos; j++)
447       DPrintf2("      #%zu: %zx\n", j, stack[j]);
448   }
449   if (pos == 0 && stack[0] == 0)
450     return;
451   pos++;
452   stk->Init(stack.data(), pos);
453 }
454 
HandleRacyStacks(ThreadState * thr,const StackTrace (& traces)[2],uptr addr_min,uptr addr_max)455 static bool HandleRacyStacks(ThreadState *thr, const StackTrace (&traces)[2],
456     uptr addr_min, uptr addr_max) {
457   Context *ctx = CTX();
458   bool equal_stack = false;
459   RacyStacks hash;
460   if (flags()->suppress_equal_stacks) {
461     hash.hash[0] = md5_hash(traces[0].Begin(), traces[0].Size() * sizeof(uptr));
462     hash.hash[1] = md5_hash(traces[1].Begin(), traces[1].Size() * sizeof(uptr));
463     for (uptr i = 0; i < ctx->racy_stacks.Size(); i++) {
464       if (hash == ctx->racy_stacks[i]) {
465         DPrintf("ThreadSanitizer: suppressing report as doubled (stack)\n");
466         equal_stack = true;
467         break;
468       }
469     }
470   }
471   bool equal_address = false;
472   RacyAddress ra0 = {addr_min, addr_max};
473   if (flags()->suppress_equal_addresses) {
474     for (uptr i = 0; i < ctx->racy_addresses.Size(); i++) {
475       RacyAddress ra2 = ctx->racy_addresses[i];
476       uptr maxbeg = max(ra0.addr_min, ra2.addr_min);
477       uptr minend = min(ra0.addr_max, ra2.addr_max);
478       if (maxbeg < minend) {
479         DPrintf("ThreadSanitizer: suppressing report as doubled (addr)\n");
480         equal_address = true;
481         break;
482       }
483     }
484   }
485   if (equal_stack || equal_address) {
486     if (!equal_stack)
487       ctx->racy_stacks.PushBack(hash);
488     if (!equal_address)
489       ctx->racy_addresses.PushBack(ra0);
490     return true;
491   }
492   return false;
493 }
494 
AddRacyStacks(ThreadState * thr,const StackTrace (& traces)[2],uptr addr_min,uptr addr_max)495 static void AddRacyStacks(ThreadState *thr, const StackTrace (&traces)[2],
496     uptr addr_min, uptr addr_max) {
497   Context *ctx = CTX();
498   if (flags()->suppress_equal_stacks) {
499     RacyStacks hash;
500     hash.hash[0] = md5_hash(traces[0].Begin(), traces[0].Size() * sizeof(uptr));
501     hash.hash[1] = md5_hash(traces[1].Begin(), traces[1].Size() * sizeof(uptr));
502     ctx->racy_stacks.PushBack(hash);
503   }
504   if (flags()->suppress_equal_addresses) {
505     RacyAddress ra0 = {addr_min, addr_max};
506     ctx->racy_addresses.PushBack(ra0);
507   }
508 }
509 
OutputReport(Context * ctx,const ScopedReport & srep,const ReportStack * suppress_stack1,const ReportStack * suppress_stack2,const ReportLocation * suppress_loc)510 bool OutputReport(Context *ctx,
511                   const ScopedReport &srep,
512                   const ReportStack *suppress_stack1,
513                   const ReportStack *suppress_stack2,
514                   const ReportLocation *suppress_loc) {
515   atomic_store(&ctx->last_symbolize_time_ns, NanoTime(), memory_order_relaxed);
516   const ReportDesc *rep = srep.GetReport();
517   Suppression *supp = 0;
518   uptr suppress_pc = IsSuppressed(rep->typ, suppress_stack1, &supp);
519   if (suppress_pc == 0)
520     suppress_pc = IsSuppressed(rep->typ, suppress_stack2, &supp);
521   if (suppress_pc == 0)
522     suppress_pc = IsSuppressed(rep->typ, suppress_loc, &supp);
523   if (suppress_pc != 0) {
524     FiredSuppression s = {srep.GetReport()->typ, suppress_pc, supp};
525     ctx->fired_suppressions.push_back(s);
526   }
527   if (OnReport(rep, suppress_pc != 0))
528     return false;
529   PrintReport(rep);
530   CTX()->nreported++;
531   return true;
532 }
533 
IsFiredSuppression(Context * ctx,const ScopedReport & srep,const StackTrace & trace)534 bool IsFiredSuppression(Context *ctx,
535                         const ScopedReport &srep,
536                         const StackTrace &trace) {
537   for (uptr k = 0; k < ctx->fired_suppressions.size(); k++) {
538     if (ctx->fired_suppressions[k].type != srep.GetReport()->typ)
539       continue;
540     for (uptr j = 0; j < trace.Size(); j++) {
541       FiredSuppression *s = &ctx->fired_suppressions[k];
542       if (trace.Get(j) == s->pc) {
543         if (s->supp)
544           s->supp->hit_count++;
545         return true;
546       }
547     }
548   }
549   return false;
550 }
551 
IsFiredSuppression(Context * ctx,const ScopedReport & srep,uptr addr)552 static bool IsFiredSuppression(Context *ctx,
553                                const ScopedReport &srep,
554                                uptr addr) {
555   for (uptr k = 0; k < ctx->fired_suppressions.size(); k++) {
556     if (ctx->fired_suppressions[k].type != srep.GetReport()->typ)
557       continue;
558     FiredSuppression *s = &ctx->fired_suppressions[k];
559     if (addr == s->pc) {
560       if (s->supp)
561         s->supp->hit_count++;
562       return true;
563     }
564   }
565   return false;
566 }
567 
FrameIsInternal(const ReportStack * frame)568 bool FrameIsInternal(const ReportStack *frame) {
569   return frame != 0 && frame->file != 0
570       && (internal_strstr(frame->file, "tsan_interceptors.cc") ||
571           internal_strstr(frame->file, "sanitizer_common_interceptors.inc") ||
572           internal_strstr(frame->file, "tsan_interface_"));
573 }
574 
575 // On programs that use Java we see weird reports like:
576 // WARNING: ThreadSanitizer: data race (pid=22512)
577 //   Read of size 8 at 0x7d2b00084318 by thread 100:
578 //     #0 memcpy tsan_interceptors.cc:406 (foo+0x00000d8dfae3)
579 //     #1 <null> <null>:0 (0x7f7ad9b40193)
580 //   Previous write of size 8 at 0x7d2b00084318 by thread 105:
581 //     #0 strncpy tsan_interceptors.cc:501 (foo+0x00000d8e0919)
582 //     #1 <null> <null>:0 (0x7f7ad9b42707)
IsJavaNonsense(const ReportDesc * rep)583 static bool IsJavaNonsense(const ReportDesc *rep) {
584 #ifndef TSAN_GO
585   for (uptr i = 0; i < rep->mops.Size(); i++) {
586     ReportMop *mop = rep->mops[i];
587     ReportStack *frame = mop->stack;
588     if (frame == 0
589         || (frame->func == 0 && frame->file == 0 && frame->line == 0
590           && frame->module == 0)) {
591       return true;
592     }
593     if (FrameIsInternal(frame)) {
594       frame = frame->next;
595       if (frame == 0
596           || (frame->func == 0 && frame->file == 0 && frame->line == 0
597           && frame->module == 0)) {
598         if (frame) {
599           FiredSuppression supp = {rep->typ, frame->pc, 0};
600           CTX()->fired_suppressions.push_back(supp);
601         }
602         return true;
603       }
604     }
605   }
606 #endif
607   return false;
608 }
609 
RaceBetweenAtomicAndFree(ThreadState * thr)610 static bool RaceBetweenAtomicAndFree(ThreadState *thr) {
611   Shadow s0(thr->racy_state[0]);
612   Shadow s1(thr->racy_state[1]);
613   CHECK(!(s0.IsAtomic() && s1.IsAtomic()));
614   if (!s0.IsAtomic() && !s1.IsAtomic())
615     return true;
616   if (s0.IsAtomic() && s1.IsFreed())
617     return true;
618   if (s1.IsAtomic() && thr->is_freeing)
619     return true;
620   return false;
621 }
622 
ReportRace(ThreadState * thr)623 void ReportRace(ThreadState *thr) {
624   if (!flags()->report_bugs)
625     return;
626   ScopedInRtl in_rtl;
627 
628   if (!flags()->report_atomic_races && !RaceBetweenAtomicAndFree(thr))
629     return;
630 
631   bool freed = false;
632   {
633     Shadow s(thr->racy_state[1]);
634     freed = s.GetFreedAndReset();
635     thr->racy_state[1] = s.raw();
636   }
637 
638   uptr addr = ShadowToMem((uptr)thr->racy_shadow_addr);
639   uptr addr_min = 0;
640   uptr addr_max = 0;
641   {
642     uptr a0 = addr + Shadow(thr->racy_state[0]).addr0();
643     uptr a1 = addr + Shadow(thr->racy_state[1]).addr0();
644     uptr e0 = a0 + Shadow(thr->racy_state[0]).size();
645     uptr e1 = a1 + Shadow(thr->racy_state[1]).size();
646     addr_min = min(a0, a1);
647     addr_max = max(e0, e1);
648     if (IsExpectedReport(addr_min, addr_max - addr_min))
649       return;
650   }
651 
652   Context *ctx = CTX();
653   ThreadRegistryLock l0(ctx->thread_registry);
654 
655   ReportType typ = ReportTypeRace;
656   if (thr->is_vptr_access)
657     typ = ReportTypeVptrRace;
658   else if (freed)
659     typ = ReportTypeUseAfterFree;
660   ScopedReport rep(typ);
661   if (IsFiredSuppression(ctx, rep, addr))
662     return;
663   const uptr kMop = 2;
664   StackTrace traces[kMop];
665   const uptr toppc = TraceTopPC(thr);
666   traces[0].ObtainCurrent(thr, toppc);
667   if (IsFiredSuppression(ctx, rep, traces[0]))
668     return;
669   InternalScopedBuffer<MutexSet> mset2(1);
670   new(mset2.data()) MutexSet();
671   Shadow s2(thr->racy_state[1]);
672   RestoreStack(s2.tid(), s2.epoch(), &traces[1], mset2.data());
673   if (IsFiredSuppression(ctx, rep, traces[1]))
674     return;
675 
676   if (HandleRacyStacks(thr, traces, addr_min, addr_max))
677     return;
678 
679   for (uptr i = 0; i < kMop; i++) {
680     Shadow s(thr->racy_state[i]);
681     rep.AddMemoryAccess(addr, s, &traces[i],
682                         i == 0 ? &thr->mset : mset2.data());
683   }
684 
685   if (flags()->suppress_java && IsJavaNonsense(rep.GetReport()))
686     return;
687 
688   for (uptr i = 0; i < kMop; i++) {
689     FastState s(thr->racy_state[i]);
690     ThreadContext *tctx = static_cast<ThreadContext*>(
691         ctx->thread_registry->GetThreadLocked(s.tid()));
692     if (s.epoch() < tctx->epoch0 || s.epoch() > tctx->epoch1)
693       continue;
694     rep.AddThread(tctx);
695   }
696 
697   rep.AddLocation(addr_min, addr_max - addr_min);
698 
699 #ifndef TSAN_GO
700   {  // NOLINT
701     Shadow s(thr->racy_state[1]);
702     if (s.epoch() <= thr->last_sleep_clock.get(s.tid()))
703       rep.AddSleep(thr->last_sleep_stack_id);
704   }
705 #endif
706 
707   ReportLocation *suppress_loc = rep.GetReport()->locs.Size() ?
708                                  rep.GetReport()->locs[0] : 0;
709   if (!OutputReport(ctx, rep, rep.GetReport()->mops[0]->stack,
710                               rep.GetReport()->mops[1]->stack,
711                               suppress_loc))
712     return;
713 
714   AddRacyStacks(thr, traces, addr_min, addr_max);
715 }
716 
PrintCurrentStack(ThreadState * thr,uptr pc)717 void PrintCurrentStack(ThreadState *thr, uptr pc) {
718   StackTrace trace;
719   trace.ObtainCurrent(thr, pc);
720   PrintStack(SymbolizeStack(trace));
721 }
722 
PrintCurrentStackSlow()723 void PrintCurrentStackSlow() {
724 #ifndef TSAN_GO
725   __sanitizer::StackTrace *ptrace = new(internal_alloc(MBlockStackTrace,
726       sizeof(__sanitizer::StackTrace))) __sanitizer::StackTrace;
727   ptrace->SlowUnwindStack(__sanitizer::StackTrace::GetCurrentPc(),
728       kStackTraceMax);
729   for (uptr i = 0; i < ptrace->size / 2; i++) {
730     uptr tmp = ptrace->trace[i];
731     ptrace->trace[i] = ptrace->trace[ptrace->size - i - 1];
732     ptrace->trace[ptrace->size - i - 1] = tmp;
733   }
734   StackTrace trace;
735   trace.Init(ptrace->trace, ptrace->size);
736   PrintStack(SymbolizeStack(trace));
737 #endif
738 }
739 
740 }  // namespace __tsan
741