1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
//===-- tsan_external.cpp -------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file is a part of ThreadSanitizer (TSan), a race detector.
//
//===----------------------------------------------------------------------===//
#include "tsan_rtl.h"
#include "sanitizer_common/sanitizer_ptrauth.h"
#if !SANITIZER_GO
# include "tsan_interceptors.h"
#endif
namespace __tsan {
#define CALLERPC ((uptr)__builtin_return_address(0))
struct TagData {
const char *object_type;
const char *header;
};
static TagData registered_tags[kExternalTagMax] = {
{},
{"Swift variable", "Swift access race"},
};
static atomic_uint32_t used_tags{kExternalTagFirstUserAvailable};
static TagData *GetTagData(uptr tag) {
// Invalid/corrupted tag? Better return NULL and let the caller deal with it.
if (tag >= atomic_load(&used_tags, memory_order_relaxed)) return nullptr;
return ®istered_tags[tag];
}
const char *GetObjectTypeFromTag(uptr tag) {
TagData *tag_data = GetTagData(tag);
return tag_data ? tag_data->object_type : nullptr;
}
const char *GetReportHeaderFromTag(uptr tag) {
TagData *tag_data = GetTagData(tag);
return tag_data ? tag_data->header : nullptr;
}
uptr TagFromShadowStackFrame(uptr pc) {
uptr tag_count = atomic_load(&used_tags, memory_order_relaxed);
void *pc_ptr = (void *)pc;
if (pc_ptr < GetTagData(0) || pc_ptr > GetTagData(tag_count - 1))
return 0;
return (TagData *)pc_ptr - GetTagData(0);
}
#if !SANITIZER_GO
// We need to track tags for individual memory accesses, but there is no space
// in the shadow cells for them. Instead we push/pop them onto the thread
// traces and ignore the extra tag frames when printing reports.
static void PushTag(ThreadState *thr, uptr tag) {
FuncEntry(thr, (uptr)®istered_tags[tag]);
}
static void PopTag(ThreadState *thr) { FuncExit(thr); }
static void ExternalAccess(void *addr, uptr caller_pc, uptr tsan_caller_pc,
void *tag, AccessType typ) {
CHECK_LT(tag, atomic_load(&used_tags, memory_order_relaxed));
bool in_ignored_lib;
if (caller_pc && libignore()->IsIgnored(caller_pc, &in_ignored_lib))
return;
ThreadState *thr = cur_thread();
if (caller_pc) FuncEntry(thr, caller_pc);
PushTag(thr, (uptr)tag);
MemoryAccess(thr, tsan_caller_pc, (uptr)addr, 1, typ);
PopTag(thr);
if (caller_pc) FuncExit(thr);
}
extern "C" {
SANITIZER_INTERFACE_ATTRIBUTE
void *__tsan_external_register_tag(const char *object_type) {
uptr new_tag = atomic_fetch_add(&used_tags, 1, memory_order_relaxed);
CHECK_LT(new_tag, kExternalTagMax);
GetTagData(new_tag)->object_type = internal_strdup(object_type);
char header[127] = {0};
internal_snprintf(header, sizeof(header), "race on %s", object_type);
GetTagData(new_tag)->header = internal_strdup(header);
return (void *)new_tag;
}
SANITIZER_INTERFACE_ATTRIBUTE
void __tsan_external_register_header(void *tag, const char *header) {
CHECK_GE((uptr)tag, kExternalTagFirstUserAvailable);
CHECK_LT((uptr)tag, kExternalTagMax);
atomic_uintptr_t *header_ptr =
(atomic_uintptr_t *)&GetTagData((uptr)tag)->header;
header = internal_strdup(header);
char *old_header =
(char *)atomic_exchange(header_ptr, (uptr)header, memory_order_seq_cst);
Free(old_header);
}
SANITIZER_INTERFACE_ATTRIBUTE
void __tsan_external_assign_tag(void *addr, void *tag) {
CHECK_LT(tag, atomic_load(&used_tags, memory_order_relaxed));
Allocator *a = allocator();
MBlock *b = nullptr;
if (a->PointerIsMine((void *)addr)) {
void *block_begin = a->GetBlockBegin((void *)addr);
if (block_begin) b = ctx->metamap.GetBlock((uptr)block_begin);
}
if (b) {
b->tag = (uptr)tag;
}
}
SANITIZER_INTERFACE_ATTRIBUTE
void __tsan_external_read(void *addr, void *caller_pc, void *tag) {
ExternalAccess(addr, STRIP_PAC_PC(caller_pc), CALLERPC, tag, kAccessRead);
}
SANITIZER_INTERFACE_ATTRIBUTE
void __tsan_external_write(void *addr, void *caller_pc, void *tag) {
ExternalAccess(addr, STRIP_PAC_PC(caller_pc), CALLERPC, tag, kAccessWrite);
}
} // extern "C"
#endif // !SANITIZER_GO
} // namespace __tsan
|
