libsanitizer/tsan/tsan_report.cpp

   1 //===-- tsan_report.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 //===----------------------------------------------------------------------===//
  12 #include "tsan_report.h"
  13 #include "tsan_platform.h"
  14 #include "tsan_rtl.h"
  15 #include "sanitizer_common/sanitizer_file.h"
  16 #include "sanitizer_common/sanitizer_placement_new.h"
  17 #include "sanitizer_common/sanitizer_report_decorator.h"
  18 #include "sanitizer_common/sanitizer_stacktrace_printer.h"
  19
  20 namespace __tsan {
  21
  22 class Decorator: public __sanitizer::SanitizerCommonDecorator {
  23  public:
  24   Decorator() : SanitizerCommonDecorator() { }
  25   const char *Access()     { return Blue(); }
  26   const char *ThreadDescription()    { return Cyan(); }
  27   const char *Location()   { return Green(); }
  28   const char *Sleep()   { return Yellow(); }
  29   const char *Mutex()   { return Magenta(); }
  30 };
  31
  32 ReportDesc::ReportDesc()
  33     : tag(kExternalTagNone)
  34     , stacks()
  35     , mops()
  36     , locs()
  37     , mutexes()
  38     , threads()
  39     , unique_tids()
  40     , sleep()
  41     , count() {
  42 }
  43
  44 ReportMop::ReportMop()
  45     : mset() {
  46 }
  47
  48 ReportDesc::~ReportDesc() {
  49   // FIXME(dvyukov): it must be leaking a lot of memory.
  50 }
  51
  52 #if !SANITIZER_GO
  53
  54 const int kThreadBufSize = 32;
  55 const char *thread_name(char *buf, Tid tid) {
  56   if (tid == kMainTid)
  57     return "main thread";
  58   internal_snprintf(buf, kThreadBufSize, "thread T%d", tid);
  59   return buf;
  60 }
  61
  62 static const char *ReportTypeString(ReportType typ, uptr tag) {
  63   switch (typ) {
  64     case ReportTypeRace:
  65       return "data race";
  66     case ReportTypeVptrRace:
  67       return "data race on vptr (ctor/dtor vs virtual call)";
  68     case ReportTypeUseAfterFree:
  69       return "heap-use-after-free";
  70     case ReportTypeVptrUseAfterFree:
  71       return "heap-use-after-free (virtual call vs free)";
  72     case ReportTypeExternalRace: {
  73       const char *str = GetReportHeaderFromTag(tag);
  74       return str ? str : "race on external object";
  75     }
  76     case ReportTypeThreadLeak:
  77       return "thread leak";
  78     case ReportTypeMutexDestroyLocked:
  79       return "destroy of a locked mutex";
  80     case ReportTypeMutexDoubleLock:
  81       return "double lock of a mutex";
  82     case ReportTypeMutexInvalidAccess:
  83       return "use of an invalid mutex (e.g. uninitialized or destroyed)";
  84     case ReportTypeMutexBadUnlock:
  85       return "unlock of an unlocked mutex (or by a wrong thread)";
  86     case ReportTypeMutexBadReadLock:
  87       return "read lock of a write locked mutex";
  88     case ReportTypeMutexBadReadUnlock:
  89       return "read unlock of a write locked mutex";
  90     case ReportTypeSignalUnsafe:
  91       return "signal-unsafe call inside of a signal";
  92     case ReportTypeErrnoInSignal:
  93       return "signal handler spoils errno";
  94     case ReportTypeDeadlock:
  95       return "lock-order-inversion (potential deadlock)";
  96     // No default case so compiler warns us if we miss one
  97   }
  98   UNREACHABLE("missing case");
  99 }
 100
 101 #if SANITIZER_APPLE
 102 static const char *const kInterposedFunctionPrefix = "wrap_";
 103 #else
 104 static const char *const kInterposedFunctionPrefix = "__interceptor_";
 105 #endif
 106
 107 void PrintStack(const ReportStack *ent) {
 108   if (ent == 0 || ent->frames == 0) {
 109     Printf("    [failed to restore the stack]\n\n");
 110     return;
 111   }
 112   SymbolizedStack *frame = ent->frames;
 113   for (int i = 0; frame && frame->info.address; frame = frame->next, i++) {
 114     InternalScopedString res;
 115     RenderFrame(&res, common_flags()->stack_trace_format, i,
 116                 frame->info.address, &frame->info,
 117                 common_flags()->symbolize_vs_style,
 118                 common_flags()->strip_path_prefix, kInterposedFunctionPrefix);
 119     Printf("%s\n", res.data());
 120   }
 121   Printf("\n");
 122 }
 123
 124 static void PrintMutexSet(Vector<ReportMopMutex> const& mset) {
 125   for (uptr i = 0; i < mset.Size(); i++) {
 126     if (i == 0)
 127       Printf(" (mutexes:");
 128     const ReportMopMutex m = mset[i];
 129     Printf(" %s M%u", m.write ? "write" : "read", m.id);
 130     Printf(i == mset.Size() - 1 ? ")" : ",");
 131   }
 132 }
 133
 134 static const char *MopDesc(bool first, bool write, bool atomic) {
 135   return atomic ? (first ? (write ? "Atomic write" : "Atomic read")
 136                 : (write ? "Previous atomic write" : "Previous atomic read"))
 137                 : (first ? (write ? "Write" : "Read")
 138                 : (write ? "Previous write" : "Previous read"));
 139 }
 140
 141 static const char *ExternalMopDesc(bool first, bool write) {
 142   return first ? (write ? "Modifying" : "Read-only")
 143                : (write ? "Previous modifying" : "Previous read-only");
 144 }
 145
 146 static void PrintMop(const ReportMop *mop, bool first) {
 147   Decorator d;
 148   char thrbuf[kThreadBufSize];
 149   Printf("%s", d.Access());
 150   if (mop->external_tag == kExternalTagNone) {
 151     Printf("  %s of size %d at %p by %s",
 152            MopDesc(first, mop->write, mop->atomic), mop->size,
 153            (void *)mop->addr, thread_name(thrbuf, mop->tid));
 154   } else {
 155     const char *object_type = GetObjectTypeFromTag(mop->external_tag);
 156     if (object_type == nullptr)
 157         object_type = "external object";
 158     Printf("  %s access of %s at %p by %s",
 159            ExternalMopDesc(first, mop->write), object_type,
 160            (void *)mop->addr, thread_name(thrbuf, mop->tid));
 161   }
 162   PrintMutexSet(mop->mset);
 163   Printf(":\n");
 164   Printf("%s", d.Default());
 165   PrintStack(mop->stack);
 166 }
 167
 168 static void PrintLocation(const ReportLocation *loc) {
 169   Decorator d;
 170   char thrbuf[kThreadBufSize];
 171   bool print_stack = false;
 172   Printf("%s", d.Location());
 173   if (loc->type == ReportLocationGlobal) {
 174     const DataInfo &global = loc->global;
 175     if (global.size != 0)
 176       Printf("  Location is global '%s' of size %zu at %p (%s+0x%zx)\n\n",
 177              global.name, global.size, reinterpret_cast<void *>(global.start),
 178              StripModuleName(global.module), global.module_offset);
 179     else
 180       Printf("  Location is global '%s' at %p (%s+0x%zx)\n\n", global.name,
 181              reinterpret_cast<void *>(global.start),
 182              StripModuleName(global.module), global.module_offset);
 183   } else if (loc->type == ReportLocationHeap) {
 184     char thrbuf[kThreadBufSize];
 185     const char *object_type = GetObjectTypeFromTag(loc->external_tag);
 186     if (!object_type) {
 187       Printf("  Location is heap block of size %zu at %p allocated by %s:\n",
 188              loc->heap_chunk_size,
 189              reinterpret_cast<void *>(loc->heap_chunk_start),
 190              thread_name(thrbuf, loc->tid));
 191     } else {
 192       Printf("  Location is %s of size %zu at %p allocated by %s:\n",
 193              object_type, loc->heap_chunk_size,
 194              reinterpret_cast<void *>(loc->heap_chunk_start),
 195              thread_name(thrbuf, loc->tid));
 196     }
 197     print_stack = true;
 198   } else if (loc->type == ReportLocationStack) {
 199     Printf("  Location is stack of %s.\n\n", thread_name(thrbuf, loc->tid));
 200   } else if (loc->type == ReportLocationTLS) {
 201     Printf("  Location is TLS of %s.\n\n", thread_name(thrbuf, loc->tid));
 202   } else if (loc->type == ReportLocationFD) {
 203     Printf("  Location is file descriptor %d %s by %s at:\n", loc->fd,
 204            loc->fd_closed ? "destroyed" : "created",
 205            thread_name(thrbuf, loc->tid));
 206     print_stack = true;
 207   }
 208   Printf("%s", d.Default());
 209   if (print_stack)
 210     PrintStack(loc->stack);
 211 }
 212
 213 static void PrintMutexShort(const ReportMutex *rm, const char *after) {
 214   Decorator d;
 215   Printf("%sM%d%s%s", d.Mutex(), rm->id, d.Default(), after);
 216 }
 217
 218 static void PrintMutexShortWithAddress(const ReportMutex *rm,
 219                                        const char *after) {
 220   Decorator d;
 221   Printf("%sM%d (%p)%s%s", d.Mutex(), rm->id,
 222          reinterpret_cast<void *>(rm->addr), d.Default(), after);
 223 }
 224
 225 static void PrintMutex(const ReportMutex *rm) {
 226   Decorator d;
 227   Printf("%s", d.Mutex());
 228   Printf("  Mutex M%u (%p) created at:\n", rm->id,
 229          reinterpret_cast<void *>(rm->addr));
 230   Printf("%s", d.Default());
 231   PrintStack(rm->stack);
 232 }
 233
 234 static void PrintThread(const ReportThread *rt) {
 235   Decorator d;
 236   if (rt->id == kMainTid)  // Little sense in describing the main thread.
 237     return;
 238   Printf("%s", d.ThreadDescription());
 239   Printf("  Thread T%d", rt->id);
 240   if (rt->name && rt->name[0] != '\0')
 241     Printf(" '%s'", rt->name);
 242   char thrbuf[kThreadBufSize];
 243   const char *thread_status = rt->running ? "running" : "finished";
 244   if (rt->thread_type == ThreadType::Worker) {
 245     Printf(" (tid=%llu, %s) is a GCD worker thread\n", rt->os_id,
 246            thread_status);
 247     Printf("\n");
 248     Printf("%s", d.Default());
 249     return;
 250   }
 251   Printf(" (tid=%llu, %s) created by %s", rt->os_id, thread_status,
 252          thread_name(thrbuf, rt->parent_tid));
 253   if (rt->stack)
 254     Printf(" at:");
 255   Printf("\n");
 256   Printf("%s", d.Default());
 257   PrintStack(rt->stack);
 258 }
 259
 260 static void PrintSleep(const ReportStack *s) {
 261   Decorator d;
 262   Printf("%s", d.Sleep());
 263   Printf("  As if synchronized via sleep:\n");
 264   Printf("%s", d.Default());
 265   PrintStack(s);
 266 }
 267
 268 static ReportStack *ChooseSummaryStack(const ReportDesc *rep) {
 269   if (rep->mops.Size())
 270     return rep->mops[0]->stack;
 271   if (rep->stacks.Size())
 272     return rep->stacks[0];
 273   if (rep->mutexes.Size())
 274     return rep->mutexes[0]->stack;
 275   if (rep->threads.Size())
 276     return rep->threads[0]->stack;
 277   return 0;
 278 }
 279
 280 static bool FrameIsInternal(const SymbolizedStack *frame) {
 281   if (frame == 0)
 282     return false;
 283   const char *file = frame->info.file;
 284   const char *module = frame->info.module;
 285   if (file != 0 &&
 286       (internal_strstr(file, "tsan_interceptors_posix.cpp") ||
 287        internal_strstr(file, "sanitizer_common_interceptors.inc") ||
 288        internal_strstr(file, "tsan_interface_")))
 289     return true;
 290   if (module != 0 && (internal_strstr(module, "libclang_rt.tsan_")))
 291     return true;
 292   return false;
 293 }
 294
 295 static SymbolizedStack *SkipTsanInternalFrames(SymbolizedStack *frames) {
 296   while (FrameIsInternal(frames) && frames->next)
 297     frames = frames->next;
 298   return frames;
 299 }
 300
 301 void PrintReport(const ReportDesc *rep) {
 302   Decorator d;
 303   Printf("==================\n");
 304   const char *rep_typ_str = ReportTypeString(rep->typ, rep->tag);
 305   Printf("%s", d.Warning());
 306   Printf("WARNING: ThreadSanitizer: %s (pid=%d)\n", rep_typ_str,
 307          (int)internal_getpid());
 308   Printf("%s", d.Default());
 309
 310   if (rep->typ == ReportTypeErrnoInSignal)
 311     Printf("  Signal %u handler invoked at:\n", rep->signum);
 312
 313   if (rep->typ == ReportTypeDeadlock) {
 314     char thrbuf[kThreadBufSize];
 315     Printf("  Cycle in lock order graph: ");
 316     for (uptr i = 0; i < rep->mutexes.Size(); i++)
 317       PrintMutexShortWithAddress(rep->mutexes[i], " => ");
 318     PrintMutexShort(rep->mutexes[0], "\n\n");
 319     CHECK_GT(rep->mutexes.Size(), 0U);
 320     CHECK_EQ(rep->mutexes.Size() * (flags()->second_deadlock_stack ? 2 : 1),
 321              rep->stacks.Size());
 322     for (uptr i = 0; i < rep->mutexes.Size(); i++) {
 323       Printf("  Mutex ");
 324       PrintMutexShort(rep->mutexes[(i + 1) % rep->mutexes.Size()],
 325                       " acquired here while holding mutex ");
 326       PrintMutexShort(rep->mutexes[i], " in ");
 327       Printf("%s", d.ThreadDescription());
 328       Printf("%s:\n", thread_name(thrbuf, rep->unique_tids[i]));
 329       Printf("%s", d.Default());
 330       if (flags()->second_deadlock_stack) {
 331         PrintStack(rep->stacks[2*i]);
 332         Printf("  Mutex ");
 333         PrintMutexShort(rep->mutexes[i],
 334                         " previously acquired by the same thread here:\n");
 335         PrintStack(rep->stacks[2*i+1]);
 336       } else {
 337         PrintStack(rep->stacks[i]);
 338         if (i == 0)
 339           Printf("    Hint: use TSAN_OPTIONS=second_deadlock_stack=1 "
 340                  "to get more informative warning message\n\n");
 341       }
 342     }
 343   } else {
 344     for (uptr i = 0; i < rep->stacks.Size(); i++) {
 345       if (i)
 346         Printf("  and:\n");
 347       PrintStack(rep->stacks[i]);
 348     }
 349   }
 350
 351   for (uptr i = 0; i < rep->mops.Size(); i++)
 352     PrintMop(rep->mops[i], i == 0);
 353
 354   if (rep->sleep)
 355     PrintSleep(rep->sleep);
 356
 357   for (uptr i = 0; i < rep->locs.Size(); i++)
 358     PrintLocation(rep->locs[i]);
 359
 360   if (rep->typ != ReportTypeDeadlock) {
 361     for (uptr i = 0; i < rep->mutexes.Size(); i++)
 362       PrintMutex(rep->mutexes[i]);
 363   }
 364
 365   for (uptr i = 0; i < rep->threads.Size(); i++)
 366     PrintThread(rep->threads[i]);
 367
 368   if (rep->typ == ReportTypeThreadLeak && rep->count > 1)
 369     Printf("  And %d more similar thread leaks.\n\n", rep->count - 1);
 370
 371   if (ReportStack *stack = ChooseSummaryStack(rep)) {
 372     if (SymbolizedStack *frame = SkipTsanInternalFrames(stack->frames))
 373       ReportErrorSummary(rep_typ_str, frame->info);
 374   }
 375
 376   if (common_flags()->print_module_map == 2)
 377     DumpProcessMap();
 378
 379   Printf("==================\n");
 380 }
 381
 382 #else  // #if !SANITIZER_GO
 383
 384 const Tid kMainGoroutineId = 1;
 385
 386 void PrintStack(const ReportStack *ent) {
 387   if (ent == 0 || ent->frames == 0) {
 388     Printf("  [failed to restore the stack]\n");
 389     return;
 390   }
 391   SymbolizedStack *frame = ent->frames;
 392   for (int i = 0; frame; frame = frame->next, i++) {
 393     const AddressInfo &info = frame->info;
 394     Printf("  %s()\n      %s:%d +0x%zx\n", info.function,
 395            StripPathPrefix(info.file, common_flags()->strip_path_prefix),
 396            info.line, info.module_offset);
 397   }
 398 }
 399
 400 static void PrintMop(const ReportMop *mop, bool first) {
 401   Printf("\n");
 402   Printf("%s at %p by ",
 403          (first ? (mop->write ? "Write" : "Read")
 404                 : (mop->write ? "Previous write" : "Previous read")),
 405          reinterpret_cast<void *>(mop->addr));
 406   if (mop->tid == kMainGoroutineId)
 407     Printf("main goroutine:\n");
 408   else
 409     Printf("goroutine %d:\n", mop->tid);
 410   PrintStack(mop->stack);
 411 }
 412
 413 static void PrintLocation(const ReportLocation *loc) {
 414   switch (loc->type) {
 415   case ReportLocationHeap: {
 416     Printf("\n");
 417     Printf("Heap block of size %zu at %p allocated by ", loc->heap_chunk_size,
 418            reinterpret_cast<void *>(loc->heap_chunk_start));
 419     if (loc->tid == kMainGoroutineId)
 420       Printf("main goroutine:\n");
 421     else
 422       Printf("goroutine %d:\n", loc->tid);
 423     PrintStack(loc->stack);
 424     break;
 425   }
 426   case ReportLocationGlobal: {
 427     Printf("\n");
 428     Printf("Global var %s of size %zu at %p declared at %s:%zu\n",
 429            loc->global.name, loc->global.size,
 430            reinterpret_cast<void *>(loc->global.start), loc->global.file,
 431            loc->global.line);
 432     break;
 433   }
 434   default:
 435     break;
 436   }
 437 }
 438
 439 static void PrintThread(const ReportThread *rt) {
 440   if (rt->id == kMainGoroutineId)
 441     return;
 442   Printf("\n");
 443   Printf("Goroutine %d (%s) created at:\n",
 444     rt->id, rt->running ? "running" : "finished");
 445   PrintStack(rt->stack);
 446 }
 447
 448 void PrintReport(const ReportDesc *rep) {
 449   Printf("==================\n");
 450   if (rep->typ == ReportTypeRace) {
 451     Printf("WARNING: DATA RACE");
 452     for (uptr i = 0; i < rep->mops.Size(); i++)
 453       PrintMop(rep->mops[i], i == 0);
 454     for (uptr i = 0; i < rep->locs.Size(); i++)
 455       PrintLocation(rep->locs[i]);
 456     for (uptr i = 0; i < rep->threads.Size(); i++)
 457       PrintThread(rep->threads[i]);
 458   } else if (rep->typ == ReportTypeDeadlock) {
 459     Printf("WARNING: DEADLOCK\n");
 460     for (uptr i = 0; i < rep->mutexes.Size(); i++) {
 461       Printf("Goroutine %d lock mutex %u while holding mutex %u:\n", 999,
 462              rep->mutexes[i]->id,
 463              rep->mutexes[(i + 1) % rep->mutexes.Size()]->id);
 464       PrintStack(rep->stacks[2*i]);
 465       Printf("\n");
 466       Printf("Mutex %u was previously locked here:\n",
 467              rep->mutexes[(i + 1) % rep->mutexes.Size()]->id);
 468       PrintStack(rep->stacks[2*i + 1]);
 469       Printf("\n");
 470     }
 471   }
 472   Printf("==================\n");
 473 }
 474
 475 #endif
 476
 477 }  // namespace __tsan