aboutsummaryrefslogtreecommitdiffstats
path: root/gcc-4.9/libsanitizer/sanitizer_common/sanitizer_posix.cc
blob: ef5cb0b03b8ec28a2a1e9851371088711bf57f1d (plain)
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
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
//===-- sanitizer_posix.cc ------------------------------------------------===//
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is shared between AddressSanitizer and ThreadSanitizer
// run-time libraries and implements POSIX-specific functions from
// sanitizer_libc.h.
//===----------------------------------------------------------------------===//

#include "sanitizer_platform.h"
#if SANITIZER_LINUX || SANITIZER_MAC

#include "sanitizer_common.h"
#include "sanitizer_libc.h"
#include "sanitizer_procmaps.h"
#include "sanitizer_stacktrace.h"

#include <sys/mman.h>

namespace __sanitizer {

// ------------- sanitizer_common.h
uptr GetMmapGranularity() {
  return GetPageSize();
}

uptr GetMaxVirtualAddress() {
#if SANITIZER_WORDSIZE == 64
# if defined(__powerpc64__)
  // On PowerPC64 we have two different address space layouts: 44- and 46-bit.
  // We somehow need to figure our which one we are using now and choose
  // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL.
  // Note that with 'ulimit -s unlimited' the stack is moved away from the top
  // of the address space, so simply checking the stack address is not enough.
  return (1ULL << 44) - 1;  // 0x00000fffffffffffUL
# else
  return (1ULL << 47) - 1;  // 0x00007fffffffffffUL;
# endif
#else  // SANITIZER_WORDSIZE == 32
  // FIXME: We can probably lower this on Android?
  return (1ULL << 32) - 1;  // 0xffffffff;
#endif  // SANITIZER_WORDSIZE
}

void *MmapOrDie(uptr size, const char *mem_type) {
  size = RoundUpTo(size, GetPageSizeCached());
  uptr res = internal_mmap(0, size,
                            PROT_READ | PROT_WRITE,
                            MAP_PRIVATE | MAP_ANON, -1, 0);
  int reserrno;
  if (internal_iserror(res, &reserrno)) {
    static int recursion_count;
    if (recursion_count) {
      // The Report() and CHECK calls below may call mmap recursively and fail.
      // If we went into recursion, just die.
      RawWrite("ERROR: Failed to mmap\n");
      Die();
    }
    recursion_count++;
    Report("ERROR: %s failed to allocate 0x%zx (%zd) bytes of %s: %d\n",
           SanitizerToolName, size, size, mem_type, reserrno);
    DumpProcessMap();
    CHECK("unable to mmap" && 0);
  }
  return (void *)res;
}

void UnmapOrDie(void *addr, uptr size) {
  if (!addr || !size) return;
  uptr res = internal_munmap(addr, size);
  if (internal_iserror(res)) {
    Report("ERROR: %s failed to deallocate 0x%zx (%zd) bytes at address %p\n",
           SanitizerToolName, size, size, addr);
    CHECK("unable to unmap" && 0);
  }
}

void *MmapFixedNoReserve(uptr fixed_addr, uptr size) {
  uptr PageSize = GetPageSizeCached();
  uptr p = internal_mmap((void*)(fixed_addr & ~(PageSize - 1)),
      RoundUpTo(size, PageSize),
      PROT_READ | PROT_WRITE,
      MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE,
      -1, 0);
  int reserrno;
  if (internal_iserror(p, &reserrno))
    Report("ERROR: "
           "%s failed to allocate 0x%zx (%zd) bytes at address %p (%d)\n",
           SanitizerToolName, size, size, fixed_addr, reserrno);
  return (void *)p;
}

void *MmapFixedOrDie(uptr fixed_addr, uptr size) {
  uptr PageSize = GetPageSizeCached();
  uptr p = internal_mmap((void*)(fixed_addr & ~(PageSize - 1)),
      RoundUpTo(size, PageSize),
      PROT_READ | PROT_WRITE,
      MAP_PRIVATE | MAP_ANON | MAP_FIXED,
      -1, 0);
  int reserrno;
  if (internal_iserror(p, &reserrno)) {
    Report("ERROR:"
           " %s failed to allocate 0x%zx (%zd) bytes at address %p (%d)\n",
           SanitizerToolName, size, size, fixed_addr, reserrno);
    CHECK("unable to mmap" && 0);
  }
  return (void *)p;
}

void *Mprotect(uptr fixed_addr, uptr size) {
  return (void *)internal_mmap((void*)fixed_addr, size,
                               PROT_NONE,
                               MAP_PRIVATE | MAP_ANON | MAP_FIXED |
                               MAP_NORESERVE, -1, 0);
}

void *MapFileToMemory(const char *file_name, uptr *buff_size) {
  uptr openrv = OpenFile(file_name, false);
  CHECK(!internal_iserror(openrv));
  fd_t fd = openrv;
  uptr fsize = internal_filesize(fd);
  CHECK_NE(fsize, (uptr)-1);
  CHECK_GT(fsize, 0);
  *buff_size = RoundUpTo(fsize, GetPageSizeCached());
  uptr map = internal_mmap(0, *buff_size, PROT_READ, MAP_PRIVATE, fd, 0);
  return internal_iserror(map) ? 0 : (void *)map;
}


static inline bool IntervalsAreSeparate(uptr start1, uptr end1,
                                        uptr start2, uptr end2) {
  CHECK(start1 <= end1);
  CHECK(start2 <= end2);
  return (end1 < start2) || (end2 < start1);
}

// FIXME: this is thread-unsafe, but should not cause problems most of the time.
// When the shadow is mapped only a single thread usually exists (plus maybe
// several worker threads on Mac, which aren't expected to map big chunks of
// memory).
bool MemoryRangeIsAvailable(uptr range_start, uptr range_end) {
  MemoryMappingLayout proc_maps(/*cache_enabled*/true);
  uptr start, end;
  while (proc_maps.Next(&start, &end,
                        /*offset*/0, /*filename*/0, /*filename_size*/0,
                        /*protection*/0)) {
    if (!IntervalsAreSeparate(start, end, range_start, range_end))
      return false;
  }
  return true;
}

void DumpProcessMap() {
  MemoryMappingLayout proc_maps(/*cache_enabled*/true);
  uptr start, end;
  const sptr kBufSize = 4095;
  char *filename = (char*)MmapOrDie(kBufSize, __FUNCTION__);
  Report("Process memory map follows:\n");
  while (proc_maps.Next(&start, &end, /* file_offset */0,
                        filename, kBufSize, /* protection */0)) {
    Printf("\t%p-%p\t%s\n", (void*)start, (void*)end, filename);
  }
  Report("End of process memory map.\n");
  UnmapOrDie(filename, kBufSize);
}

const char *GetPwd() {
  return GetEnv("PWD");
}

char *FindPathToBinary(const char *name) {
  const char *path = GetEnv("PATH");
  if (!path)
    return 0;
  uptr name_len = internal_strlen(name);
  InternalScopedBuffer<char> buffer(kMaxPathLength);
  const char *beg = path;
  while (true) {
    const char *end = internal_strchrnul(beg, ':');
    uptr prefix_len = end - beg;
    if (prefix_len + name_len + 2 <= kMaxPathLength) {
      internal_memcpy(buffer.data(), beg, prefix_len);
      buffer[prefix_len] = '/';
      internal_memcpy(&buffer[prefix_len + 1], name, name_len);
      buffer[prefix_len + 1 + name_len] = '\0';
      if (FileExists(buffer.data()))
        return internal_strdup(buffer.data());
    }
    if (*end == '\0') break;
    beg = end + 1;
  }
  return 0;
}

void MaybeOpenReportFile() {
  if (!log_to_file) return;
  uptr pid = internal_getpid();
  // If in tracer, use the parent's file.
  if (pid == stoptheworld_tracer_pid)
    pid = stoptheworld_tracer_ppid;
  if (report_fd_pid == pid) return;
  InternalScopedBuffer<char> report_path_full(4096);
  internal_snprintf(report_path_full.data(), report_path_full.size(),
                    "%s.%d", report_path_prefix, pid);
  uptr openrv = OpenFile(report_path_full.data(), true);
  if (internal_iserror(openrv)) {
    report_fd = kStderrFd;
    log_to_file = false;
    Report("ERROR: Can't open file: %s\n", report_path_full.data());
    Die();
  }
  if (report_fd != kInvalidFd) {
    // We're in the child. Close the parent's log.
    internal_close(report_fd);
  }
  report_fd = openrv;
  report_fd_pid = pid;
}

void RawWrite(const char *buffer) {
  static const char *kRawWriteError =
      "RawWrite can't output requested buffer!\n";
  uptr length = (uptr)internal_strlen(buffer);
  MaybeOpenReportFile();
  if (length != internal_write(report_fd, buffer, length)) {
    internal_write(report_fd, kRawWriteError, internal_strlen(kRawWriteError));
    Die();
  }
}

bool GetCodeRangeForFile(const char *module, uptr *start, uptr *end) {
  uptr s, e, off, prot;
  InternalScopedString buff(4096);
  MemoryMappingLayout proc_maps(/*cache_enabled*/false);
  while (proc_maps.Next(&s, &e, &off, buff.data(), buff.size(), &prot)) {
    if ((prot & MemoryMappingLayout::kProtectionExecute) != 0
        && internal_strcmp(module, buff.data()) == 0) {
      *start = s;
      *end = e;
      return true;
    }
  }
  return false;
}

}  // namespace __sanitizer

#endif  // SANITIZER_LINUX || SANITIZER_MAC