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
|
//===-- asan_posix.cc -----------------------------------------------------===//
//
// 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.
//
// Posix-specific details.
//===----------------------------------------------------------------------===//
#include "sanitizer_common/sanitizer_platform.h"
#if SANITIZER_LINUX || SANITIZER_MAC
#include "asan_internal.h"
#include "asan_interceptors.h"
#include "asan_mapping.h"
#include "asan_report.h"
#include "asan_stack.h"
#include "sanitizer_common/sanitizer_libc.h"
#include "sanitizer_common/sanitizer_procmaps.h"
#include <pthread.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <unistd.h>
static const uptr kAltStackSize = SIGSTKSZ * 4; // SIGSTKSZ is not enough.
namespace __asan {
static void MaybeInstallSigaction(int signum,
void (*handler)(int, siginfo_t *, void *)) {
if (!AsanInterceptsSignal(signum))
return;
struct sigaction sigact;
REAL(memset)(&sigact, 0, sizeof(sigact));
sigact.sa_sigaction = handler;
sigact.sa_flags = SA_SIGINFO;
if (flags()->use_sigaltstack) sigact.sa_flags |= SA_ONSTACK;
CHECK_EQ(0, REAL(sigaction)(signum, &sigact, 0));
if (common_flags()->verbosity >= 1) {
Report("Installed the sigaction for signal %d\n", signum);
}
}
static void ASAN_OnSIGSEGV(int, siginfo_t *siginfo, void *context) {
uptr addr = (uptr)siginfo->si_addr;
// Write the first message using the bullet-proof write.
if (13 != internal_write(2, "ASAN:SIGSEGV\n", 13)) Die();
uptr pc, sp, bp;
GetPcSpBp(context, &pc, &sp, &bp);
ReportSIGSEGV(pc, sp, bp, addr);
}
void SetAlternateSignalStack() {
stack_t altstack, oldstack;
CHECK_EQ(0, sigaltstack(0, &oldstack));
// If the alternate stack is already in place, do nothing.
if ((oldstack.ss_flags & SS_DISABLE) == 0) return;
// TODO(glider): the mapped stack should have the MAP_STACK flag in the
// future. It is not required by man 2 sigaltstack now (they're using
// malloc()).
void* base = MmapOrDie(kAltStackSize, __FUNCTION__);
altstack.ss_sp = base;
altstack.ss_flags = 0;
altstack.ss_size = kAltStackSize;
CHECK_EQ(0, sigaltstack(&altstack, 0));
if (common_flags()->verbosity > 0) {
Report("Alternative stack for T%d set: [%p,%p)\n",
GetCurrentTidOrInvalid(),
altstack.ss_sp, (char*)altstack.ss_sp + altstack.ss_size);
}
}
void UnsetAlternateSignalStack() {
stack_t altstack, oldstack;
altstack.ss_sp = 0;
altstack.ss_flags = SS_DISABLE;
altstack.ss_size = 0;
CHECK_EQ(0, sigaltstack(&altstack, &oldstack));
UnmapOrDie(oldstack.ss_sp, oldstack.ss_size);
}
void InstallSignalHandlers() {
// Set the alternate signal stack for the main thread.
// This will cause SetAlternateSignalStack to be called twice, but the stack
// will be actually set only once.
if (flags()->use_sigaltstack) SetAlternateSignalStack();
MaybeInstallSigaction(SIGSEGV, ASAN_OnSIGSEGV);
MaybeInstallSigaction(SIGBUS, ASAN_OnSIGSEGV);
}
// ---------------------- TSD ---------------- {{{1
static pthread_key_t tsd_key;
static bool tsd_key_inited = false;
void AsanTSDInit(void (*destructor)(void *tsd)) {
CHECK(!tsd_key_inited);
tsd_key_inited = true;
CHECK_EQ(0, pthread_key_create(&tsd_key, destructor));
}
void *AsanTSDGet() {
CHECK(tsd_key_inited);
return pthread_getspecific(tsd_key);
}
void AsanTSDSet(void *tsd) {
CHECK(tsd_key_inited);
pthread_setspecific(tsd_key, tsd);
}
void PlatformTSDDtor(void *tsd) {
AsanThreadContext *context = (AsanThreadContext*)tsd;
if (context->destructor_iterations > 1) {
context->destructor_iterations--;
CHECK_EQ(0, pthread_setspecific(tsd_key, tsd));
return;
}
AsanThread::TSDDtor(tsd);
}
} // namespace __asan
#endif // SANITIZER_LINUX || SANITIZER_MAC
|
