lib/tsan/rtl/tsan_rtl_report.cc

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