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.
26 static 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.
37 SANITIZER_WEAK_DEFAULT_IMPL
__tsan_default_suppressions()38 const char *__tsan_default_suppressions() {
39   return 0;
40 }
41 #endif
42 
43 namespace __tsan {
44 
45 ALIGNED(64) static char suppression_placeholder[sizeof(SuppressionContext)];
46 static SuppressionContext *suppression_ctx = nullptr;
47 static const char *kSuppressionTypes[] = {
48     kSuppressionRace,   kSuppressionRaceTop, kSuppressionMutex,
49     kSuppressionThread, kSuppressionSignal, kSuppressionLib,
50     kSuppressionDeadlock};
51 
InitializeSuppressions()52 void 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 
Suppressions()63 SuppressionContext *Suppressions() {
64   CHECK(suppression_ctx);
65   return suppression_ctx;
66 }
67 
conv(ReportType typ)68 static 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 == ReportTypeMutexBadUnlock)
84     return kSuppressionMutex;
85   else if (typ == ReportTypeMutexBadReadLock)
86     return kSuppressionMutex;
87   else if (typ == ReportTypeMutexBadReadUnlock)
88     return kSuppressionMutex;
89   else if (typ == ReportTypeSignalUnsafe)
90     return kSuppressionSignal;
91   else if (typ == ReportTypeErrnoInSignal)
92     return kSuppressionNone;
93   else if (typ == ReportTypeDeadlock)
94     return kSuppressionDeadlock;
95   Printf("ThreadSanitizer: unknown report type %d\n", typ),
96   Die();
97 }
98 
IsSuppressed(const char * stype,const AddressInfo & info,Suppression ** sp)99 static uptr IsSuppressed(const char *stype, const AddressInfo &info,
100     Suppression **sp) {
101   if (suppression_ctx->Match(info.function, stype, sp) ||
102       suppression_ctx->Match(info.file, stype, sp) ||
103       suppression_ctx->Match(info.module, stype, sp)) {
104     VPrintf(2, "ThreadSanitizer: matched suppression '%s'\n", (*sp)->templ);
105     atomic_fetch_add(&(*sp)->hit_count, 1, memory_order_relaxed);
106     return info.address;
107   }
108   return 0;
109 }
110 
IsSuppressed(ReportType typ,const ReportStack * stack,Suppression ** sp)111 uptr IsSuppressed(ReportType typ, const ReportStack *stack, Suppression **sp) {
112   CHECK(suppression_ctx);
113   if (!suppression_ctx->SuppressionCount() || stack == 0 ||
114       !stack->suppressable)
115     return 0;
116   const char *stype = conv(typ);
117   if (0 == internal_strcmp(stype, kSuppressionNone))
118     return 0;
119   for (const SymbolizedStack *frame = stack->frames; frame;
120       frame = frame->next) {
121     uptr pc = IsSuppressed(stype, frame->info, sp);
122     if (pc != 0)
123       return pc;
124   }
125   if (0 == internal_strcmp(stype, kSuppressionRace) && stack->frames != nullptr)
126     return IsSuppressed(kSuppressionRaceTop, stack->frames->info, sp);
127   return 0;
128 }
129 
IsSuppressed(ReportType typ,const ReportLocation * loc,Suppression ** sp)130 uptr IsSuppressed(ReportType typ, const ReportLocation *loc, Suppression **sp) {
131   CHECK(suppression_ctx);
132   if (!suppression_ctx->SuppressionCount() || loc == 0 ||
133       loc->type != ReportLocationGlobal || !loc->suppressable)
134     return 0;
135   const char *stype = conv(typ);
136   if (0 == internal_strcmp(stype, kSuppressionNone))
137     return 0;
138   Suppression *s;
139   const DataInfo &global = loc->global;
140   if (suppression_ctx->Match(global.name, stype, &s) ||
141       suppression_ctx->Match(global.module, stype, &s)) {
142       VPrintf(2, "ThreadSanitizer: matched suppression '%s'\n", s->templ);
143       atomic_fetch_add(&s->hit_count, 1, memory_order_relaxed);
144       *sp = s;
145       return global.start;
146   }
147   return 0;
148 }
149 
PrintMatchedSuppressions()150 void PrintMatchedSuppressions() {
151   InternalMmapVector<Suppression *> matched(1);
152   CHECK(suppression_ctx);
153   suppression_ctx->GetMatched(&matched);
154   if (!matched.size())
155     return;
156   int hit_count = 0;
157   for (uptr i = 0; i < matched.size(); i++)
158     hit_count += atomic_load_relaxed(&matched[i]->hit_count);
159   Printf("ThreadSanitizer: Matched %d suppressions (pid=%d):\n", hit_count,
160          (int)internal_getpid());
161   for (uptr i = 0; i < matched.size(); i++) {
162     Printf("%d %s:%s\n", matched[i]->hit_count, matched[i]->type,
163            matched[i]->templ);
164   }
165 }
166 }  // namespace __tsan
167