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
__tsan_default_suppressions()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
InitializeSuppressions()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
Suppressions()62 SuppressionContext *Suppressions() {
63 CHECK(suppression_ctx);
64 return suppression_ctx;
65 }
66
conv(ReportType typ)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
IsSuppressed(const char * stype,const AddressInfo & info,Suppression ** sp)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
IsSuppressed(ReportType typ,const ReportStack * stack,Suppression ** sp)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
IsSuppressed(ReportType typ,const ReportLocation * loc,Suppression ** sp)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
PrintMatchedSuppressions()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
162