libsanitizer/tsan/tsan_suppressions.cpp

   1 //===-- tsan_suppressions.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
  13 #include "sanitizer_common/sanitizer_common.h"
  14 #include "sanitizer_common/sanitizer_libc.h"
  15 #include "sanitizer_common/sanitizer_placement_new.h"
  16 #include "sanitizer_common/sanitizer_suppressions.h"
  17 #include "tsan_suppressions.h"
  18 #include "tsan_rtl.h"
  19 #include "tsan_flags.h"
  20 #include "tsan_mman.h"
  21 #include "tsan_platform.h"
  22
  23 #if !SANITIZER_GO
  24 // Suppressions for true/false positives in standard libraries.
  25 static const char *const std_suppressions =
  26 // Libstdc++ 4.4 has data races in std::string.
  27 // See http://crbug.com/181502 for an example.
  28 "race:^_M_rep$\n"
  29 "race:^_M_is_leaked$\n"
  30 // False positive when using std <thread>.
  31 // Happens because we miss atomic synchronization in libstdc++.
  32 // See http://llvm.org/bugs/show_bug.cgi?id=17066 for details.
  33 "race:std::_Sp_counted_ptr_inplace<std::thread::_Impl\n";
  34
  35 // Can be overriden in frontend.
  36 SANITIZER_WEAK_DEFAULT_IMPL
  37 const char *__tsan_default_suppressions() {
  38   return 0;
  39 }
  40 #endif
  41
  42 namespace __tsan {
  43
  44 ALIGNED(64) static char suppression_placeholder[sizeof(SuppressionContext)];
  45 static SuppressionContext *suppression_ctx = nullptr;
  46 static const char *kSuppressionTypes[] = {
  47     kSuppressionRace,   kSuppressionRaceTop, kSuppressionMutex,
  48     kSuppressionThread, kSuppressionSignal, kSuppressionLib,
  49     kSuppressionDeadlock};
  50
  51 void InitializeSuppressions() {
  52   CHECK_EQ(nullptr, suppression_ctx);
  53   suppression_ctx = new (suppression_placeholder)
  54       SuppressionContext(kSuppressionTypes, ARRAY_SIZE(kSuppressionTypes));
  55   suppression_ctx->ParseFromFile(flags()->suppressions);
  56 #if !SANITIZER_GO
  57   suppression_ctx->Parse(__tsan_default_suppressions());
  58   suppression_ctx->Parse(std_suppressions);
  59 #endif
  60 }
  61
  62 SuppressionContext *Suppressions() {
  63   CHECK(suppression_ctx);
  64   return suppression_ctx;
  65 }
  66
  67 static const char *conv(ReportType typ) {
  68   switch (typ) {
  69     case ReportTypeRace:
  70     case ReportTypeVptrRace:
  71     case ReportTypeUseAfterFree:
  72     case ReportTypeVptrUseAfterFree:
  73     case ReportTypeExternalRace:
  74       return kSuppressionRace;
  75     case ReportTypeThreadLeak:
  76       return kSuppressionThread;
  77     case ReportTypeMutexDestroyLocked:
  78     case ReportTypeMutexDoubleLock:
  79     case ReportTypeMutexInvalidAccess:
  80     case ReportTypeMutexBadUnlock:
  81     case ReportTypeMutexBadReadLock:
  82     case ReportTypeMutexBadReadUnlock:
  83       return kSuppressionMutex;
  84     case ReportTypeSignalUnsafe:
  85     case ReportTypeErrnoInSignal:
  86       return kSuppressionSignal;
  87     case ReportTypeDeadlock:
  88       return kSuppressionDeadlock;
  89     // No default case so compiler warns us if we miss one
  90   }
  91   UNREACHABLE("missing case");
  92 }
  93
  94 static uptr IsSuppressed(const char *stype, const AddressInfo &info,
  95     Suppression **sp) {
  96   if (suppression_ctx->Match(info.function, stype, sp) ||
  97       suppression_ctx->Match(info.file, stype, sp) ||
  98       suppression_ctx->Match(info.module, stype, sp)) {
  99     VPrintf(2, "ThreadSanitizer: matched suppression '%s'\n", (*sp)->templ);
 100     atomic_fetch_add(&(*sp)->hit_count, 1, memory_order_relaxed);
 101     return info.address;
 102   }
 103   return 0;
 104 }
 105
 106 uptr IsSuppressed(ReportType typ, const ReportStack *stack, Suppression **sp) {
 107   CHECK(suppression_ctx);
 108   if (!suppression_ctx->SuppressionCount() || stack == 0 ||
 109       !stack->suppressable)
 110     return 0;
 111   const char *stype = conv(typ);
 112   if (0 == internal_strcmp(stype, kSuppressionNone))
 113     return 0;
 114   for (const SymbolizedStack *frame = stack->frames; frame;
 115       frame = frame->next) {
 116     uptr pc = IsSuppressed(stype, frame->info, sp);
 117     if (pc != 0)
 118       return pc;
 119   }
 120   if (0 == internal_strcmp(stype, kSuppressionRace) && stack->frames != nullptr)
 121     return IsSuppressed(kSuppressionRaceTop, stack->frames->info, sp);
 122   return 0;
 123 }
 124
 125 uptr IsSuppressed(ReportType typ, const ReportLocation *loc, Suppression **sp) {
 126   CHECK(suppression_ctx);
 127   if (!suppression_ctx->SuppressionCount() || loc == 0 ||
 128       loc->type != ReportLocationGlobal || !loc->suppressable)
 129     return 0;
 130   const char *stype = conv(typ);
 131   if (0 == internal_strcmp(stype, kSuppressionNone))
 132     return 0;
 133   Suppression *s;
 134   const DataInfo &global = loc->global;
 135   if (suppression_ctx->Match(global.name, stype, &s) ||
 136       suppression_ctx->Match(global.module, stype, &s)) {
 137       VPrintf(2, "ThreadSanitizer: matched suppression '%s'\n", s->templ);
 138       atomic_fetch_add(&s->hit_count, 1, memory_order_relaxed);
 139       *sp = s;
 140       return global.start;
 141   }
 142   return 0;
 143 }
 144
 145 void PrintMatchedSuppressions() {
 146   InternalMmapVector<Suppression *> matched;
 147   CHECK(suppression_ctx);
 148   suppression_ctx->GetMatched(&matched);
 149   if (!matched.size())
 150     return;
 151   int hit_count = 0;
 152   for (uptr i = 0; i < matched.size(); i++)
 153     hit_count += atomic_load_relaxed(&matched[i]->hit_count);
 154   Printf("ThreadSanitizer: Matched %d suppressions (pid=%d):\n", hit_count,
 155          (int)internal_getpid());
 156   for (uptr i = 0; i < matched.size(); i++) {
 157     Printf("%d %s:%s\n", atomic_load_relaxed(&matched[i]->hit_count),
 158            matched[i]->type, matched[i]->templ);
 159   }
 160 }
 161 }  // namespace __tsan