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
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
|
//===-- asan_descriptions.cc ------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of AddressSanitizer, an address sanity checker.
//
// ASan functions for getting information about an address and/or printing it.
//===----------------------------------------------------------------------===//
#include "asan_descriptions.h"
#include "asan_mapping.h"
#include "sanitizer_common/sanitizer_stackdepot.h"
namespace __asan {
// Return " (thread_name) " or an empty string if the name is empty.
const char *ThreadNameWithParenthesis(AsanThreadContext *t, char buff[],
uptr buff_len) {
const char *name = t->name;
if (name[0] == '\0') return "";
buff[0] = 0;
internal_strncat(buff, " (", 3);
internal_strncat(buff, name, buff_len - 4);
internal_strncat(buff, ")", 2);
return buff;
}
const char *ThreadNameWithParenthesis(u32 tid, char buff[], uptr buff_len) {
if (tid == kInvalidTid) return "";
asanThreadRegistry().CheckLocked();
AsanThreadContext *t = GetThreadContextByTidLocked(tid);
return ThreadNameWithParenthesis(t, buff, buff_len);
}
void DescribeThread(AsanThreadContext *context) {
CHECK(context);
asanThreadRegistry().CheckLocked();
// No need to announce the main thread.
if (context->tid == 0 || context->announced) {
return;
}
context->announced = true;
char tname[128];
InternalScopedString str(1024);
str.append("Thread T%d%s", context->tid,
ThreadNameWithParenthesis(context->tid, tname, sizeof(tname)));
if (context->parent_tid == kInvalidTid) {
str.append(" created by unknown thread\n");
Printf("%s", str.data());
return;
}
str.append(
" created by T%d%s here:\n", context->parent_tid,
ThreadNameWithParenthesis(context->parent_tid, tname, sizeof(tname)));
Printf("%s", str.data());
StackDepotGet(context->stack_id).Print();
// Recursively described parent thread if needed.
if (flags()->print_full_thread_history) {
AsanThreadContext *parent_context =
GetThreadContextByTidLocked(context->parent_tid);
DescribeThread(parent_context);
}
}
// Shadow descriptions
static bool GetShadowKind(uptr addr, ShadowKind *shadow_kind) {
CHECK(!AddrIsInMem(addr));
if (AddrIsInShadowGap(addr)) {
*shadow_kind = kShadowKindGap;
} else if (AddrIsInHighShadow(addr)) {
*shadow_kind = kShadowKindHigh;
} else if (AddrIsInLowShadow(addr)) {
*shadow_kind = kShadowKindLow;
} else {
CHECK(0 && "Address is not in memory and not in shadow?");
return false;
}
return true;
}
bool DescribeAddressIfShadow(uptr addr) {
ShadowAddressDescription descr;
if (!GetShadowAddressInformation(addr, &descr)) return false;
Printf("Address %p is located in the %s area.\n", addr,
ShadowNames[descr.kind]);
return true;
}
bool GetShadowAddressInformation(uptr addr, ShadowAddressDescription *descr) {
if (AddrIsInMem(addr)) return false;
ShadowKind shadow_kind;
if (!GetShadowKind(addr, &shadow_kind)) return false;
if (shadow_kind != kShadowKindGap) descr->shadow_byte = *(u8 *)addr;
descr->addr = addr;
descr->kind = shadow_kind;
return true;
}
// Heap descriptions
static void GetAccessToHeapChunkInformation(ChunkAccess *descr,
AsanChunkView chunk, uptr addr,
uptr access_size) {
descr->bad_addr = addr;
if (chunk.AddrIsAtLeft(addr, access_size, &descr->offset)) {
descr->access_type = kAccessTypeLeft;
} else if (chunk.AddrIsAtRight(addr, access_size, &descr->offset)) {
descr->access_type = kAccessTypeRight;
if (descr->offset < 0) {
descr->bad_addr -= descr->offset;
descr->offset = 0;
}
} else if (chunk.AddrIsInside(addr, access_size, &descr->offset)) {
descr->access_type = kAccessTypeInside;
} else {
descr->access_type = kAccessTypeUnknown;
}
descr->chunk_begin = chunk.Beg();
descr->chunk_size = chunk.UsedSize();
descr->alloc_type = chunk.GetAllocType();
}
static void PrintHeapChunkAccess(uptr addr, const ChunkAccess &descr) {
Decorator d;
InternalScopedString str(4096);
str.append("%s", d.Location());
switch (descr.access_type) {
case kAccessTypeLeft:
str.append("%p is located %zd bytes to the left of",
(void *)descr.bad_addr, descr.offset);
break;
case kAccessTypeRight:
str.append("%p is located %zd bytes to the right of",
(void *)descr.bad_addr, descr.offset);
break;
case kAccessTypeInside:
str.append("%p is located %zd bytes inside of", (void *)descr.bad_addr,
descr.offset);
break;
case kAccessTypeUnknown:
str.append(
"%p is located somewhere around (this is AddressSanitizer bug!)",
(void *)descr.bad_addr);
}
str.append(" %zu-byte region [%p,%p)\n", descr.chunk_size,
(void *)descr.chunk_begin,
(void *)(descr.chunk_begin + descr.chunk_size));
str.append("%s", d.EndLocation());
Printf("%s", str.data());
}
bool GetHeapAddressInformation(uptr addr, uptr access_size,
HeapAddressDescription *descr) {
AsanChunkView chunk = FindHeapChunkByAddress(addr);
if (!chunk.IsValid()) {
return false;
}
descr->addr = addr;
GetAccessToHeapChunkInformation(&descr->chunk_access, chunk, addr,
access_size);
CHECK_NE(chunk.AllocTid(), kInvalidTid);
descr->alloc_tid = chunk.AllocTid();
descr->alloc_stack_id = chunk.GetAllocStackId();
descr->free_tid = chunk.FreeTid();
if (descr->free_tid != kInvalidTid)
descr->free_stack_id = chunk.GetFreeStackId();
return true;
}
static StackTrace GetStackTraceFromId(u32 id) {
CHECK(id);
StackTrace res = StackDepotGet(id);
CHECK(res.trace);
return res;
}
bool DescribeAddressIfHeap(uptr addr, uptr access_size) {
HeapAddressDescription descr;
if (!GetHeapAddressInformation(addr, access_size, &descr)) {
Printf(
"AddressSanitizer can not describe address in more detail "
"(wild memory access suspected).\n");
return false;
}
PrintHeapChunkAccess(addr, descr.chunk_access);
asanThreadRegistry().CheckLocked();
AsanThreadContext *alloc_thread =
GetThreadContextByTidLocked(descr.alloc_tid);
StackTrace alloc_stack = GetStackTraceFromId(descr.alloc_stack_id);
char tname[128];
Decorator d;
AsanThreadContext *free_thread = nullptr;
if (descr.free_tid != kInvalidTid) {
free_thread = GetThreadContextByTidLocked(descr.free_tid);
Printf("%sfreed by thread T%d%s here:%s\n", d.Allocation(),
free_thread->tid,
ThreadNameWithParenthesis(free_thread, tname, sizeof(tname)),
d.EndAllocation());
StackTrace free_stack = GetStackTraceFromId(descr.free_stack_id);
free_stack.Print();
Printf("%spreviously allocated by thread T%d%s here:%s\n", d.Allocation(),
alloc_thread->tid,
ThreadNameWithParenthesis(alloc_thread, tname, sizeof(tname)),
d.EndAllocation());
} else {
Printf("%sallocated by thread T%d%s here:%s\n", d.Allocation(),
alloc_thread->tid,
ThreadNameWithParenthesis(alloc_thread, tname, sizeof(tname)),
d.EndAllocation());
}
alloc_stack.Print();
DescribeThread(GetCurrentThread());
if (free_thread) DescribeThread(free_thread);
DescribeThread(alloc_thread);
return true;
}
} // namespace __asan
|
