1//===-- asan_posix.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 AddressSanitizer, an address sanity checker.
11//
12// Posix-specific details.
13//===----------------------------------------------------------------------===//
14
15#include "sanitizer_common/sanitizer_platform.h"
16#if SANITIZER_POSIX
17
18#include "asan_internal.h"
19#include "asan_interceptors.h"
20#include "asan_mapping.h"
21#include "asan_report.h"
22#include "asan_stack.h"
23#include "sanitizer_common/sanitizer_libc.h"
24#include "sanitizer_common/sanitizer_procmaps.h"
25
26#include <pthread.h>
27#include <signal.h>
28#include <stdlib.h>
29#include <sys/time.h>
30#include <sys/resource.h>
31#include <unistd.h>
32
33namespace __asan {
34
35void AsanOnSIGSEGV(int, void *siginfo, void *context) {
36  uptr addr = (uptr)((siginfo_t*)siginfo)->si_addr;
37  int code = (int)((siginfo_t*)siginfo)->si_code;
38  // Write the first message using the bullet-proof write.
39  if (13 != internal_write(2, "ASAN:SIGSEGV\n", 13)) Die();
40  uptr pc, sp, bp;
41  GetPcSpBp(context, &pc, &sp, &bp);
42
43  // Access at a reasonable offset above SP, or slightly below it (to account
44  // for x86_64 redzone, ARM push of multiple registers, etc) is probably a
45  // stack overflow.
46  // We also check si_code to filter out SEGV caused by something else other
47  // then hitting the guard page or unmapped memory, like, for example,
48  // unaligned memory access.
49  if (addr + 128 > sp && addr < sp + 0xFFFF &&
50      (code == si_SEGV_MAPERR || code == si_SEGV_ACCERR))
51    ReportStackOverflow(pc, sp, bp, context, addr);
52  else
53    ReportSIGSEGV(pc, sp, bp, context, addr);
54}
55
56// ---------------------- TSD ---------------- {{{1
57
58static pthread_key_t tsd_key;
59static bool tsd_key_inited = false;
60void AsanTSDInit(void (*destructor)(void *tsd)) {
61  CHECK(!tsd_key_inited);
62  tsd_key_inited = true;
63  CHECK_EQ(0, pthread_key_create(&tsd_key, destructor));
64}
65
66void *AsanTSDGet() {
67  CHECK(tsd_key_inited);
68  return pthread_getspecific(tsd_key);
69}
70
71void AsanTSDSet(void *tsd) {
72  CHECK(tsd_key_inited);
73  pthread_setspecific(tsd_key, tsd);
74}
75
76void PlatformTSDDtor(void *tsd) {
77  AsanThreadContext *context = (AsanThreadContext*)tsd;
78  if (context->destructor_iterations > 1) {
79    context->destructor_iterations--;
80    CHECK_EQ(0, pthread_setspecific(tsd_key, tsd));
81    return;
82  }
83  AsanThread::TSDDtor(tsd);
84}
85}  // namespace __asan
86
87#endif  // SANITIZER_POSIX
88