libsanitizer/lsan/lsan_common.cc

   1 //=-- lsan_common.cc ------------------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of LeakSanitizer.
   9 // Implementation of common leak checking functionality.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "lsan_common.h"
  14
  15 #include "sanitizer_common/sanitizer_common.h"
  16 #include "sanitizer_common/sanitizer_flags.h"
  17 #include "sanitizer_common/sanitizer_placement_new.h"
  18 #include "sanitizer_common/sanitizer_procmaps.h"
  19 #include "sanitizer_common/sanitizer_stackdepot.h"
  20 #include "sanitizer_common/sanitizer_stacktrace.h"
  21 #include "sanitizer_common/sanitizer_stoptheworld.h"
  22 #include "sanitizer_common/sanitizer_suppressions.h"
  23 #include "sanitizer_common/sanitizer_report_decorator.h"
  24
  25 #if CAN_SANITIZE_LEAKS
  26 namespace __lsan {
  27
  28 // This mutex is used to prevent races between DoLeakCheck and IgnoreObject, and
  29 // also to protect the global list of root regions.
  30 BlockingMutex global_mutex(LINKER_INITIALIZED);
  31
  32 THREADLOCAL int disable_counter;
  33 bool DisabledInThisThread() { return disable_counter > 0; }
  34
  35 Flags lsan_flags;
  36
  37 static void InitializeFlags(bool standalone) {
  38   Flags *f = flags();
  39   // Default values.
  40   f->report_objects = false;
  41   f->resolution = 0;
  42   f->max_leaks = 0;
  43   f->exitcode = 23;
  44   f->use_registers = true;
  45   f->use_globals = true;
  46   f->use_stacks = true;
  47   f->use_tls = true;
  48   f->use_root_regions = true;
  49   f->use_unaligned = false;
  50   f->use_poisoned = false;
  51   f->log_pointers = false;
  52   f->log_threads = false;
  53
  54   const char *options = GetEnv("LSAN_OPTIONS");
  55   if (options) {
  56     ParseFlag(options, &f->use_registers, "use_registers", "");
  57     ParseFlag(options, &f->use_globals, "use_globals", "");
  58     ParseFlag(options, &f->use_stacks, "use_stacks", "");
  59     ParseFlag(options, &f->use_tls, "use_tls", "");
  60     ParseFlag(options, &f->use_root_regions, "use_root_regions", "");
  61     ParseFlag(options, &f->use_unaligned, "use_unaligned", "");
  62     ParseFlag(options, &f->use_poisoned, "use_poisoned", "");
  63     ParseFlag(options, &f->report_objects, "report_objects", "");
  64     ParseFlag(options, &f->resolution, "resolution", "");
  65     CHECK_GE(&f->resolution, 0);
  66     ParseFlag(options, &f->max_leaks, "max_leaks", "");
  67     CHECK_GE(&f->max_leaks, 0);
  68     ParseFlag(options, &f->log_pointers, "log_pointers", "");
  69     ParseFlag(options, &f->log_threads, "log_threads", "");
  70     ParseFlag(options, &f->exitcode, "exitcode", "");
  71   }
  72
  73   // Set defaults for common flags (only in standalone mode) and parse
  74   // them from LSAN_OPTIONS.
  75   CommonFlags *cf = common_flags();
  76   if (standalone) {
  77     SetCommonFlagsDefaults(cf);
  78     cf->external_symbolizer_path = GetEnv("LSAN_SYMBOLIZER_PATH");
  79     cf->malloc_context_size = 30;
  80     cf->detect_leaks = true;
  81   }
  82   ParseCommonFlagsFromString(cf, options);
  83 }
  84
  85 #define LOG_POINTERS(...)                           \
  86   do {                                              \
  87     if (flags()->log_pointers) Report(__VA_ARGS__); \
  88   } while (0);
  89
  90 #define LOG_THREADS(...)                           \
  91   do {                                             \
  92     if (flags()->log_threads) Report(__VA_ARGS__); \
  93   } while (0);
  94
  95 static bool suppressions_inited = false;
  96
  97 void InitializeSuppressions() {
  98   CHECK(!suppressions_inited);
  99   SuppressionContext::InitIfNecessary();
 100   if (&__lsan_default_suppressions)
 101     SuppressionContext::Get()->Parse(__lsan_default_suppressions());
 102   suppressions_inited = true;
 103 }
 104
 105 struct RootRegion {
 106   const void *begin;
 107   uptr size;
 108 };
 109
 110 InternalMmapVector<RootRegion> *root_regions;
 111
 112 void InitializeRootRegions() {
 113   CHECK(!root_regions);
 114   ALIGNED(64) static char placeholder[sizeof(InternalMmapVector<RootRegion>)];
 115   root_regions = new(placeholder) InternalMmapVector<RootRegion>(1);
 116 }
 117
 118 void InitCommonLsan(bool standalone) {
 119   InitializeFlags(standalone);
 120   InitializeRootRegions();
 121   if (common_flags()->detect_leaks) {
 122     // Initialization which can fail or print warnings should only be done if
 123     // LSan is actually enabled.
 124     InitializeSuppressions();
 125     InitializePlatformSpecificModules();
 126   }
 127 }
 128
 129 class Decorator: public __sanitizer::SanitizerCommonDecorator {
 130  public:
 131   Decorator() : SanitizerCommonDecorator() { }
 132   const char *Error() { return Red(); }
 133   const char *Leak() { return Blue(); }
 134   const char *End() { return Default(); }
 135 };
 136
 137 static inline bool CanBeAHeapPointer(uptr p) {
 138   // Since our heap is located in mmap-ed memory, we can assume a sensible lower
 139   // bound on heap addresses.
 140   const uptr kMinAddress = 4 * 4096;
 141   if (p < kMinAddress) return false;
 142 #ifdef __x86_64__
 143   // Accept only canonical form user-space addresses.
 144   return ((p >> 47) == 0);
 145 #else
 146   return true;
 147 #endif
 148 }
 149
 150 // Scans the memory range, looking for byte patterns that point into allocator
 151 // chunks. Marks those chunks with |tag| and adds them to |frontier|.
 152 // There are two usage modes for this function: finding reachable or ignored
 153 // chunks (|tag| = kReachable or kIgnored) and finding indirectly leaked chunks
 154 // (|tag| = kIndirectlyLeaked). In the second case, there's no flood fill,
 155 // so |frontier| = 0.
 156 void ScanRangeForPointers(uptr begin, uptr end,
 157                           Frontier *frontier,
 158                           const char *region_type, ChunkTag tag) {
 159   const uptr alignment = flags()->pointer_alignment();
 160   LOG_POINTERS("Scanning %s range %p-%p.\n", region_type, begin, end);
 161   uptr pp = begin;
 162   if (pp % alignment)
 163     pp = pp + alignment - pp % alignment;
 164   for (; pp + sizeof(void *) <= end; pp += alignment) {  // NOLINT
 165     void *p = *reinterpret_cast<void **>(pp);
 166     if (!CanBeAHeapPointer(reinterpret_cast<uptr>(p))) continue;
 167     uptr chunk = PointsIntoChunk(p);
 168     if (!chunk) continue;
 169     // Pointers to self don't count. This matters when tag == kIndirectlyLeaked.
 170     if (chunk == begin) continue;
 171     LsanMetadata m(chunk);
 172     // Reachable beats ignored beats leaked.
 173     if (m.tag() == kReachable) continue;
 174     if (m.tag() == kIgnored && tag != kReachable) continue;
 175
 176     // Do this check relatively late so we can log only the interesting cases.
 177     if (!flags()->use_poisoned && WordIsPoisoned(pp)) {
 178       LOG_POINTERS(
 179           "%p is poisoned: ignoring %p pointing into chunk %p-%p of size "
 180           "%zu.\n",
 181           pp, p, chunk, chunk + m.requested_size(), m.requested_size());
 182       continue;
 183     }
 184
 185     m.set_tag(tag);
 186     LOG_POINTERS("%p: found %p pointing into chunk %p-%p of size %zu.\n", pp, p,
 187                  chunk, chunk + m.requested_size(), m.requested_size());
 188     if (frontier)
 189       frontier->push_back(chunk);
 190   }
 191 }
 192
 193 void ForEachExtraStackRangeCb(uptr begin, uptr end, void* arg) {
 194   Frontier *frontier = reinterpret_cast<Frontier *>(arg);
 195   ScanRangeForPointers(begin, end, frontier, "FAKE STACK", kReachable);
 196 }
 197
 198 // Scans thread data (stacks and TLS) for heap pointers.
 199 static void ProcessThreads(SuspendedThreadsList const &suspended_threads,
 200                            Frontier *frontier) {
 201   InternalScopedBuffer<uptr> registers(SuspendedThreadsList::RegisterCount());
 202   uptr registers_begin = reinterpret_cast<uptr>(registers.data());
 203   uptr registers_end = registers_begin + registers.size();
 204   for (uptr i = 0; i < suspended_threads.thread_count(); i++) {
 205     uptr os_id = static_cast<uptr>(suspended_threads.GetThreadID(i));
 206     LOG_THREADS("Processing thread %d.\n", os_id);
 207     uptr stack_begin, stack_end, tls_begin, tls_end, cache_begin, cache_end;
 208     bool thread_found = GetThreadRangesLocked(os_id, &stack_begin, &stack_end,
 209                                               &tls_begin, &tls_end,
 210                                               &cache_begin, &cache_end);
 211     if (!thread_found) {
 212       // If a thread can't be found in the thread registry, it's probably in the
 213       // process of destruction. Log this event and move on.
 214       LOG_THREADS("Thread %d not found in registry.\n", os_id);
 215       continue;
 216     }
 217     uptr sp;
 218     bool have_registers =
 219         (suspended_threads.GetRegistersAndSP(i, registers.data(), &sp) == 0);
 220     if (!have_registers) {
 221       Report("Unable to get registers from thread %d.\n");
 222       // If unable to get SP, consider the entire stack to be reachable.
 223       sp = stack_begin;
 224     }
 225
 226     if (flags()->use_registers && have_registers)
 227       ScanRangeForPointers(registers_begin, registers_end, frontier,
 228                            "REGISTERS", kReachable);
 229
 230     if (flags()->use_stacks) {
 231       LOG_THREADS("Stack at %p-%p (SP = %p).\n", stack_begin, stack_end, sp);
 232       if (sp < stack_begin || sp >= stack_end) {
 233         // SP is outside the recorded stack range (e.g. the thread is running a
 234         // signal handler on alternate stack). Again, consider the entire stack
 235         // range to be reachable.
 236         LOG_THREADS("WARNING: stack pointer not in stack range.\n");
 237       } else {
 238         // Shrink the stack range to ignore out-of-scope values.
 239         stack_begin = sp;
 240       }
 241       ScanRangeForPointers(stack_begin, stack_end, frontier, "STACK",
 242                            kReachable);
 243       ForEachExtraStackRange(os_id, ForEachExtraStackRangeCb, frontier);
 244     }
 245
 246     if (flags()->use_tls) {
 247       LOG_THREADS("TLS at %p-%p.\n", tls_begin, tls_end);
 248       if (cache_begin == cache_end) {
 249         ScanRangeForPointers(tls_begin, tls_end, frontier, "TLS", kReachable);
 250       } else {
 251         // Because LSan should not be loaded with dlopen(), we can assume
 252         // that allocator cache will be part of static TLS image.
 253         CHECK_LE(tls_begin, cache_begin);
 254         CHECK_GE(tls_end, cache_end);
 255         if (tls_begin < cache_begin)
 256           ScanRangeForPointers(tls_begin, cache_begin, frontier, "TLS",
 257                                kReachable);
 258         if (tls_end > cache_end)
 259           ScanRangeForPointers(cache_end, tls_end, frontier, "TLS", kReachable);
 260       }
 261     }
 262   }
 263 }
 264
 265 static void ProcessRootRegion(Frontier *frontier, uptr root_begin,
 266                               uptr root_end) {
 267   MemoryMappingLayout proc_maps(/*cache_enabled*/true);
 268   uptr begin, end, prot;
 269   while (proc_maps.Next(&begin, &end,
 270                         /*offset*/ 0, /*filename*/ 0, /*filename_size*/ 0,
 271                         &prot)) {
 272     uptr intersection_begin = Max(root_begin, begin);
 273     uptr intersection_end = Min(end, root_end);
 274     if (intersection_begin >= intersection_end) continue;
 275     bool is_readable = prot & MemoryMappingLayout::kProtectionRead;
 276     LOG_POINTERS("Root region %p-%p intersects with mapped region %p-%p (%s)\n",
 277                  root_begin, root_end, begin, end,
 278                  is_readable ? "readable" : "unreadable");
 279     if (is_readable)
 280       ScanRangeForPointers(intersection_begin, intersection_end, frontier,
 281                            "ROOT", kReachable);
 282   }
 283 }
 284
 285 // Scans root regions for heap pointers.
 286 static void ProcessRootRegions(Frontier *frontier) {
 287   if (!flags()->use_root_regions) return;
 288   CHECK(root_regions);
 289   for (uptr i = 0; i < root_regions->size(); i++) {
 290     RootRegion region = (*root_regions)[i];
 291     uptr begin_addr = reinterpret_cast<uptr>(region.begin);
 292     ProcessRootRegion(frontier, begin_addr, begin_addr + region.size);
 293   }
 294 }
 295
 296 static void FloodFillTag(Frontier *frontier, ChunkTag tag) {
 297   while (frontier->size()) {
 298     uptr next_chunk = frontier->back();
 299     frontier->pop_back();
 300     LsanMetadata m(next_chunk);
 301     ScanRangeForPointers(next_chunk, next_chunk + m.requested_size(), frontier,
 302                          "HEAP", tag);
 303   }
 304 }
 305
 306 // ForEachChunk callback. If the chunk is marked as leaked, marks all chunks
 307 // which are reachable from it as indirectly leaked.
 308 static void MarkIndirectlyLeakedCb(uptr chunk, void *arg) {
 309   chunk = GetUserBegin(chunk);
 310   LsanMetadata m(chunk);
 311   if (m.allocated() && m.tag() != kReachable) {
 312     ScanRangeForPointers(chunk, chunk + m.requested_size(),
 313                          /* frontier */ 0, "HEAP", kIndirectlyLeaked);
 314   }
 315 }
 316
 317 // ForEachChunk callback. If chunk is marked as ignored, adds its address to
 318 // frontier.
 319 static void CollectIgnoredCb(uptr chunk, void *arg) {
 320   CHECK(arg);
 321   chunk = GetUserBegin(chunk);
 322   LsanMetadata m(chunk);
 323   if (m.allocated() && m.tag() == kIgnored)
 324     reinterpret_cast<Frontier *>(arg)->push_back(chunk);
 325 }
 326
 327 // Sets the appropriate tag on each chunk.
 328 static void ClassifyAllChunks(SuspendedThreadsList const &suspended_threads) {
 329   // Holds the flood fill frontier.
 330   Frontier frontier(1);
 331
 332   ProcessGlobalRegions(&frontier);
 333   ProcessThreads(suspended_threads, &frontier);
 334   ProcessRootRegions(&frontier);
 335   FloodFillTag(&frontier, kReachable);
 336   // The check here is relatively expensive, so we do this in a separate flood
 337   // fill. That way we can skip the check for chunks that are reachable
 338   // otherwise.
 339   LOG_POINTERS("Processing platform-specific allocations.\n");
 340   ProcessPlatformSpecificAllocations(&frontier);
 341   FloodFillTag(&frontier, kReachable);
 342
 343   LOG_POINTERS("Scanning ignored chunks.\n");
 344   CHECK_EQ(0, frontier.size());
 345   ForEachChunk(CollectIgnoredCb, &frontier);
 346   FloodFillTag(&frontier, kIgnored);
 347
 348   // Iterate over leaked chunks and mark those that are reachable from other
 349   // leaked chunks.
 350   LOG_POINTERS("Scanning leaked chunks.\n");
 351   ForEachChunk(MarkIndirectlyLeakedCb, 0 /* arg */);
 352 }
 353
 354 static void PrintStackTraceById(u32 stack_trace_id) {
 355   CHECK(stack_trace_id);
 356   uptr size = 0;
 357   const uptr *trace = StackDepotGet(stack_trace_id, &size);
 358   StackTrace::PrintStack(trace, size);
 359 }
 360
 361 // ForEachChunk callback. Aggregates information about unreachable chunks into
 362 // a LeakReport.
 363 static void CollectLeaksCb(uptr chunk, void *arg) {
 364   CHECK(arg);
 365   LeakReport *leak_report = reinterpret_cast<LeakReport *>(arg);
 366   chunk = GetUserBegin(chunk);
 367   LsanMetadata m(chunk);
 368   if (!m.allocated()) return;
 369   if (m.tag() == kDirectlyLeaked || m.tag() == kIndirectlyLeaked) {
 370     uptr resolution = flags()->resolution;
 371     u32 stack_trace_id = 0;
 372     if (resolution > 0) {
 373       uptr size = 0;
 374       const uptr *trace = StackDepotGet(m.stack_trace_id(), &size);
 375       size = Min(size, resolution);
 376       stack_trace_id = StackDepotPut(trace, size);
 377     } else {
 378       stack_trace_id = m.stack_trace_id();
 379     }
 380     leak_report->AddLeakedChunk(chunk, stack_trace_id, m.requested_size(),
 381                                 m.tag());
 382   }
 383 }
 384
 385 static void PrintMatchedSuppressions() {
 386   InternalMmapVector<Suppression *> matched(1);
 387   SuppressionContext::Get()->GetMatched(&matched);
 388   if (!matched.size())
 389     return;
 390   const char *line = "-----------------------------------------------------";
 391   Printf("%s\n", line);
 392   Printf("Suppressions used:\n");
 393   Printf("  count      bytes template\n");
 394   for (uptr i = 0; i < matched.size(); i++)
 395     Printf("%7zu %10zu %s\n", static_cast<uptr>(matched[i]->hit_count),
 396            matched[i]->weight, matched[i]->templ);
 397   Printf("%s\n\n", line);
 398 }
 399
 400 struct DoLeakCheckParam {
 401   bool success;
 402   LeakReport leak_report;
 403 };
 404
 405 static void DoLeakCheckCallback(const SuspendedThreadsList &suspended_threads,
 406                                 void *arg) {
 407   DoLeakCheckParam *param = reinterpret_cast<DoLeakCheckParam *>(arg);
 408   CHECK(param);
 409   CHECK(!param->success);
 410   ClassifyAllChunks(suspended_threads);
 411   ForEachChunk(CollectLeaksCb, &param->leak_report);
 412   param->success = true;
 413 }
 414
 415 void DoLeakCheck() {
 416   EnsureMainThreadIDIsCorrect();
 417   BlockingMutexLock l(&global_mutex);
 418   static bool already_done;
 419   if (already_done) return;
 420   already_done = true;
 421   if (&__lsan_is_turned_off && __lsan_is_turned_off())
 422       return;
 423
 424   DoLeakCheckParam param;
 425   param.success = false;
 426   LockThreadRegistry();
 427   LockAllocator();
 428   StopTheWorld(DoLeakCheckCallback, &param);
 429   UnlockAllocator();
 430   UnlockThreadRegistry();
 431
 432   if (!param.success) {
 433     Report("LeakSanitizer has encountered a fatal error.\n");
 434     Die();
 435   }
 436   param.leak_report.ApplySuppressions();
 437   uptr unsuppressed_count = param.leak_report.UnsuppressedLeakCount();
 438   if (unsuppressed_count > 0) {
 439     Decorator d;
 440     Printf("\n"
 441            "================================================================="
 442            "\n");
 443     Printf("%s", d.Error());
 444     Report("ERROR: LeakSanitizer: detected memory leaks\n");
 445     Printf("%s", d.End());
 446     param.leak_report.ReportTopLeaks(flags()->max_leaks);
 447   }
 448   if (common_flags()->print_suppressions)
 449     PrintMatchedSuppressions();
 450   if (unsuppressed_count > 0) {
 451     param.leak_report.PrintSummary();
 452     if (flags()->exitcode)
 453       internal__exit(flags()->exitcode);
 454   }
 455 }
 456
 457 static Suppression *GetSuppressionForAddr(uptr addr) {
 458   Suppression *s;
 459
 460   // Suppress by module name.
 461   const char *module_name;
 462   uptr module_offset;
 463   if (Symbolizer::GetOrInit()
 464           ->GetModuleNameAndOffsetForPC(addr, &module_name, &module_offset) &&
 465       SuppressionContext::Get()->Match(module_name, SuppressionLeak, &s))
 466     return s;
 467
 468   // Suppress by file or function name.
 469   static const uptr kMaxAddrFrames = 16;
 470   InternalScopedBuffer<AddressInfo> addr_frames(kMaxAddrFrames);
 471   for (uptr i = 0; i < kMaxAddrFrames; i++) new (&addr_frames[i]) AddressInfo();
 472   uptr addr_frames_num = Symbolizer::GetOrInit()->SymbolizePC(
 473       addr, addr_frames.data(), kMaxAddrFrames);
 474   for (uptr i = 0; i < addr_frames_num; i++) {
 475     if (SuppressionContext::Get()->Match(addr_frames[i].function,
 476                                          SuppressionLeak, &s) ||
 477         SuppressionContext::Get()->Match(addr_frames[i].file, SuppressionLeak,
 478                                          &s))
 479       return s;
 480   }
 481   return 0;
 482 }
 483
 484 static Suppression *GetSuppressionForStack(u32 stack_trace_id) {
 485   uptr size = 0;
 486   const uptr *trace = StackDepotGet(stack_trace_id, &size);
 487   for (uptr i = 0; i < size; i++) {
 488     Suppression *s =
 489         GetSuppressionForAddr(StackTrace::GetPreviousInstructionPc(trace[i]));
 490     if (s) return s;
 491   }
 492   return 0;
 493 }
 494
 495 ///// LeakReport implementation. /////
 496
 497 // A hard limit on the number of distinct leaks, to avoid quadratic complexity
 498 // in LeakReport::AddLeakedChunk(). We don't expect to ever see this many leaks
 499 // in real-world applications.
 500 // FIXME: Get rid of this limit by changing the implementation of LeakReport to
 501 // use a hash table.
 502 const uptr kMaxLeaksConsidered = 5000;
 503
 504 void LeakReport::AddLeakedChunk(uptr chunk, u32 stack_trace_id,
 505                                 uptr leaked_size, ChunkTag tag) {
 506   CHECK(tag == kDirectlyLeaked || tag == kIndirectlyLeaked);
 507   bool is_directly_leaked = (tag == kDirectlyLeaked);
 508   uptr i;
 509   for (i = 0; i < leaks_.size(); i++) {
 510     if (leaks_[i].stack_trace_id == stack_trace_id &&
 511         leaks_[i].is_directly_leaked == is_directly_leaked) {
 512       leaks_[i].hit_count++;
 513       leaks_[i].total_size += leaked_size;
 514       break;
 515     }
 516   }
 517   if (i == leaks_.size()) {
 518     if (leaks_.size() == kMaxLeaksConsidered) return;
 519     Leak leak = { next_id_++, /* hit_count */ 1, leaked_size, stack_trace_id,
 520                   is_directly_leaked, /* is_suppressed */ false };
 521     leaks_.push_back(leak);
 522   }
 523   if (flags()->report_objects) {
 524     LeakedObject obj = {leaks_[i].id, chunk, leaked_size};
 525     leaked_objects_.push_back(obj);
 526   }
 527 }
 528
 529 static bool LeakComparator(const Leak &leak1, const Leak &leak2) {
 530   if (leak1.is_directly_leaked == leak2.is_directly_leaked)
 531     return leak1.total_size > leak2.total_size;
 532   else
 533     return leak1.is_directly_leaked;
 534 }
 535
 536 void LeakReport::ReportTopLeaks(uptr num_leaks_to_report) {
 537   CHECK(leaks_.size() <= kMaxLeaksConsidered);
 538   Printf("\n");
 539   if (leaks_.size() == kMaxLeaksConsidered)
 540     Printf("Too many leaks! Only the first %zu leaks encountered will be "
 541            "reported.\n",
 542            kMaxLeaksConsidered);
 543
 544   uptr unsuppressed_count = UnsuppressedLeakCount();
 545   if (num_leaks_to_report > 0 && num_leaks_to_report < unsuppressed_count)
 546     Printf("The %zu top leak(s):\n", num_leaks_to_report);
 547   InternalSort(&leaks_, leaks_.size(), LeakComparator);
 548   uptr leaks_reported = 0;
 549   for (uptr i = 0; i < leaks_.size(); i++) {
 550     if (leaks_[i].is_suppressed) continue;
 551     PrintReportForLeak(i);
 552     leaks_reported++;
 553     if (leaks_reported == num_leaks_to_report) break;
 554   }
 555   if (leaks_reported < unsuppressed_count) {
 556     uptr remaining = unsuppressed_count - leaks_reported;
 557     Printf("Omitting %zu more leak(s).\n", remaining);
 558   }
 559 }
 560
 561 void LeakReport::PrintReportForLeak(uptr index) {
 562   Decorator d;
 563   Printf("%s", d.Leak());
 564   Printf("%s leak of %zu byte(s) in %zu object(s) allocated from:\n",
 565          leaks_[index].is_directly_leaked ? "Direct" : "Indirect",
 566          leaks_[index].total_size, leaks_[index].hit_count);
 567   Printf("%s", d.End());
 568
 569   PrintStackTraceById(leaks_[index].stack_trace_id);
 570
 571   if (flags()->report_objects) {
 572     Printf("Objects leaked above:\n");
 573     PrintLeakedObjectsForLeak(index);
 574     Printf("\n");
 575   }
 576 }
 577
 578 void LeakReport::PrintLeakedObjectsForLeak(uptr index) {
 579   u32 leak_id = leaks_[index].id;
 580   for (uptr j = 0; j < leaked_objects_.size(); j++) {
 581     if (leaked_objects_[j].leak_id == leak_id)
 582       Printf("%p (%zu bytes)\n", leaked_objects_[j].addr,
 583              leaked_objects_[j].size);
 584   }
 585 }
 586
 587 void LeakReport::PrintSummary() {
 588   CHECK(leaks_.size() <= kMaxLeaksConsidered);
 589   uptr bytes = 0, allocations = 0;
 590   for (uptr i = 0; i < leaks_.size(); i++) {
 591       if (leaks_[i].is_suppressed) continue;
 592       bytes += leaks_[i].total_size;
 593       allocations += leaks_[i].hit_count;
 594   }
 595   InternalScopedBuffer<char> summary(kMaxSummaryLength);
 596   internal_snprintf(summary.data(), summary.size(),
 597                     "%zu byte(s) leaked in %zu allocation(s).", bytes,
 598                     allocations);
 599   ReportErrorSummary(summary.data());
 600 }
 601
 602 void LeakReport::ApplySuppressions() {
 603   for (uptr i = 0; i < leaks_.size(); i++) {
 604     Suppression *s = GetSuppressionForStack(leaks_[i].stack_trace_id);
 605     if (s) {
 606       s->weight += leaks_[i].total_size;
 607       s->hit_count += leaks_[i].hit_count;
 608       leaks_[i].is_suppressed = true;
 609     }
 610   }
 611 }
 612
 613 uptr LeakReport::UnsuppressedLeakCount() {
 614   uptr result = 0;
 615   for (uptr i = 0; i < leaks_.size(); i++)
 616     if (!leaks_[i].is_suppressed) result++;
 617   return result;
 618 }
 619
 620 }  // namespace __lsan
 621 #endif  // CAN_SANITIZE_LEAKS
 622
 623 using namespace __lsan;  // NOLINT
 624
 625 extern "C" {
 626 SANITIZER_INTERFACE_ATTRIBUTE
 627 void __lsan_ignore_object(const void *p) {
 628 #if CAN_SANITIZE_LEAKS
 629   if (!common_flags()->detect_leaks)
 630     return;
 631   // Cannot use PointsIntoChunk or LsanMetadata here, since the allocator is not
 632   // locked.
 633   BlockingMutexLock l(&global_mutex);
 634   IgnoreObjectResult res = IgnoreObjectLocked(p);
 635   if (res == kIgnoreObjectInvalid)
 636     VReport(1, "__lsan_ignore_object(): no heap object found at %p", p);
 637   if (res == kIgnoreObjectAlreadyIgnored)
 638     VReport(1, "__lsan_ignore_object(): "
 639            "heap object at %p is already being ignored\n", p);
 640   if (res == kIgnoreObjectSuccess)
 641     VReport(1, "__lsan_ignore_object(): ignoring heap object at %p\n", p);
 642 #endif  // CAN_SANITIZE_LEAKS
 643 }
 644
 645 SANITIZER_INTERFACE_ATTRIBUTE
 646 void __lsan_register_root_region(const void *begin, uptr size) {
 647 #if CAN_SANITIZE_LEAKS
 648   BlockingMutexLock l(&global_mutex);
 649   CHECK(root_regions);
 650   RootRegion region = {begin, size};
 651   root_regions->push_back(region);
 652   VReport(1, "Registered root region at %p of size %llu\n", begin, size);
 653 #endif  // CAN_SANITIZE_LEAKS
 654 }
 655
 656 SANITIZER_INTERFACE_ATTRIBUTE
 657 void __lsan_unregister_root_region(const void *begin, uptr size) {
 658 #if CAN_SANITIZE_LEAKS
 659   BlockingMutexLock l(&global_mutex);
 660   CHECK(root_regions);
 661   bool removed = false;
 662   for (uptr i = 0; i < root_regions->size(); i++) {
 663     RootRegion region = (*root_regions)[i];
 664     if (region.begin == begin && region.size == size) {
 665       removed = true;
 666       uptr last_index = root_regions->size() - 1;
 667       (*root_regions)[i] = (*root_regions)[last_index];
 668       root_regions->pop_back();
 669       VReport(1, "Unregistered root region at %p of size %llu\n", begin, size);
 670       break;
 671     }
 672   }
 673   if (!removed) {
 674     Report(
 675         "__lsan_unregister_root_region(): region at %p of size %llu has not "
 676         "been registered.\n",
 677         begin, size);
 678     Die();
 679   }
 680 #endif  // CAN_SANITIZE_LEAKS
 681 }
 682
 683 SANITIZER_INTERFACE_ATTRIBUTE
 684 void __lsan_disable() {
 685 #if CAN_SANITIZE_LEAKS
 686   __lsan::disable_counter++;
 687 #endif
 688 }
 689
 690 SANITIZER_INTERFACE_ATTRIBUTE
 691 void __lsan_enable() {
 692 #if CAN_SANITIZE_LEAKS
 693   if (!__lsan::disable_counter && common_flags()->detect_leaks) {
 694     Report("Unmatched call to __lsan_enable().\n");
 695     Die();
 696   }
 697   __lsan::disable_counter--;
 698 #endif
 699 }
 700
 701 SANITIZER_INTERFACE_ATTRIBUTE
 702 void __lsan_do_leak_check() {
 703 #if CAN_SANITIZE_LEAKS
 704   if (common_flags()->detect_leaks)
 705     __lsan::DoLeakCheck();
 706 #endif  // CAN_SANITIZE_LEAKS
 707 }
 708
 709 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
 710 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 711 int __lsan_is_turned_off() {
 712   return 0;
 713 }
 714 #endif
 715 }  // extern "C"