1//===-- tsan_suppressions.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_common.h"
15#include "sanitizer_common/sanitizer_libc.h"
16#include "sanitizer_common/sanitizer_placement_new.h"
17#include "sanitizer_common/sanitizer_suppressions.h"
18#include "tsan_suppressions.h"
19#include "tsan_rtl.h"
20#include "tsan_flags.h"
21#include "tsan_mman.h"
22#include "tsan_platform.h"
23
24#ifndef SANITIZER_GO
25// Suppressions for true/false positives in standard libraries.
26static const char *const std_suppressions =
27// Libstdc++ 4.4 has data races in std::string.
28// See http://crbug.com/181502 for an example.
29"race:^_M_rep$\n"
30"race:^_M_is_leaked$\n"
31// False positive when using std <thread>.
32// Happens because we miss atomic synchronization in libstdc++.
33// See http://llvm.org/bugs/show_bug.cgi?id=17066 for details.
34"race:std::_Sp_counted_ptr_inplace<std::thread::_Impl\n";
35
36// Can be overriden in frontend.
37SANITIZER_WEAK_DEFAULT_IMPL
38const char *__tsan_default_suppressions() {
39  return 0;
40}
41#endif
42
43namespace __tsan {
44
45ALIGNED(64) static char suppression_placeholder[sizeof(SuppressionContext)];
46static SuppressionContext *suppression_ctx = nullptr;
47static const char *kSuppressionTypes[] = {
48    kSuppressionRace,   kSuppressionRaceTop, kSuppressionMutex,
49    kSuppressionThread, kSuppressionSignal, kSuppressionLib,
50    kSuppressionDeadlock};
51
52void InitializeSuppressions() {
53  CHECK_EQ(nullptr, suppression_ctx);
54  suppression_ctx = new (suppression_placeholder) // NOLINT
55      SuppressionContext(kSuppressionTypes, ARRAY_SIZE(kSuppressionTypes));
56  suppression_ctx->ParseFromFile(flags()->suppressions);
57#ifndef SANITIZER_GO
58  suppression_ctx->Parse(__tsan_default_suppressions());
59  suppression_ctx->Parse(std_suppressions);
60#endif
61}
62
63SuppressionContext *Suppressions() {
64  CHECK(suppression_ctx);
65  return suppression_ctx;
66}
67
68static const char *conv(ReportType typ) {
69  if (typ == ReportTypeRace)
70    return kSuppressionRace;
71  else if (typ == ReportTypeVptrRace)
72    return kSuppressionRace;
73  else if (typ == ReportTypeUseAfterFree)
74    return kSuppressionRace;
75  else if (typ == ReportTypeVptrUseAfterFree)
76    return kSuppressionRace;
77  else if (typ == ReportTypeThreadLeak)
78    return kSuppressionThread;
79  else if (typ == ReportTypeMutexDestroyLocked)
80    return kSuppressionMutex;
81  else if (typ == ReportTypeMutexDoubleLock)
82    return kSuppressionMutex;
83  else if (typ == ReportTypeMutexInvalidAccess)
84    return kSuppressionMutex;
85  else if (typ == ReportTypeMutexBadUnlock)
86    return kSuppressionMutex;
87  else if (typ == ReportTypeMutexBadReadLock)
88    return kSuppressionMutex;
89  else if (typ == ReportTypeMutexBadReadUnlock)
90    return kSuppressionMutex;
91  else if (typ == ReportTypeSignalUnsafe)
92    return kSuppressionSignal;
93  else if (typ == ReportTypeErrnoInSignal)
94    return kSuppressionNone;
95  else if (typ == ReportTypeDeadlock)
96    return kSuppressionDeadlock;
97  Printf("ThreadSanitizer: unknown report type %d\n", typ);
98  Die();
99}
100
101static uptr IsSuppressed(const char *stype, const AddressInfo &info,
102    Suppression **sp) {
103  if (suppression_ctx->Match(info.function, stype, sp) ||
104      suppression_ctx->Match(info.file, stype, sp) ||
105      suppression_ctx->Match(info.module, stype, sp)) {
106    VPrintf(2, "ThreadSanitizer: matched suppression '%s'\n", (*sp)->templ);
107    atomic_fetch_add(&(*sp)->hit_count, 1, memory_order_relaxed);
108    return info.address;
109  }
110  return 0;
111}
112
113uptr IsSuppressed(ReportType typ, const ReportStack *stack, Suppression **sp) {
114  CHECK(suppression_ctx);
115  if (!suppression_ctx->SuppressionCount() || stack == 0 ||
116      !stack->suppressable)
117    return 0;
118  const char *stype = conv(typ);
119  if (0 == internal_strcmp(stype, kSuppressionNone))
120    return 0;
121  for (const SymbolizedStack *frame = stack->frames; frame;
122      frame = frame->next) {
123    uptr pc = IsSuppressed(stype, frame->info, sp);
124    if (pc != 0)
125      return pc;
126  }
127  if (0 == internal_strcmp(stype, kSuppressionRace) && stack->frames != nullptr)
128    return IsSuppressed(kSuppressionRaceTop, stack->frames->info, sp);
129  return 0;
130}
131
132uptr IsSuppressed(ReportType typ, const ReportLocation *loc, Suppression **sp) {
133  CHECK(suppression_ctx);
134  if (!suppression_ctx->SuppressionCount() || loc == 0 ||
135      loc->type != ReportLocationGlobal || !loc->suppressable)
136    return 0;
137  const char *stype = conv(typ);
138  if (0 == internal_strcmp(stype, kSuppressionNone))
139    return 0;
140  Suppression *s;
141  const DataInfo &global = loc->global;
142  if (suppression_ctx->Match(global.name, stype, &s) ||
143      suppression_ctx->Match(global.module, stype, &s)) {
144      VPrintf(2, "ThreadSanitizer: matched suppression '%s'\n", s->templ);
145      atomic_fetch_add(&s->hit_count, 1, memory_order_relaxed);
146      *sp = s;
147      return global.start;
148  }
149  return 0;
150}
151
152void PrintMatchedSuppressions() {
153  InternalMmapVector<Suppression *> matched(1);
154  CHECK(suppression_ctx);
155  suppression_ctx->GetMatched(&matched);
156  if (!matched.size())
157    return;
158  int hit_count = 0;
159  for (uptr i = 0; i < matched.size(); i++)
160    hit_count += atomic_load_relaxed(&matched[i]->hit_count);
161  Printf("ThreadSanitizer: Matched %d suppressions (pid=%d):\n", hit_count,
162         (int)internal_getpid());
163  for (uptr i = 0; i < matched.size(); i++) {
164    Printf("%d %s:%s\n", atomic_load_relaxed(&matched[i]->hit_count),
165           matched[i]->type, matched[i]->templ);
166  }
167}
168}  // namespace __tsan
169