libsanitizer/sanitizer_common/sanitizer_posix.cc

   1 //===-- sanitizer_posix.cc ------------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is shared between AddressSanitizer and ThreadSanitizer
   9 // run-time libraries and implements POSIX-specific functions from
  10 // sanitizer_posix.h.
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "sanitizer_platform.h"
  14
  15 #if SANITIZER_POSIX
  16
  17 #include "sanitizer_common.h"
  18 #include "sanitizer_file.h"
  19 #include "sanitizer_libc.h"
  20 #include "sanitizer_posix.h"
  21 #include "sanitizer_procmaps.h"
  22 #include "sanitizer_stacktrace.h"
  23
  24 #include <errno.h>
  25 #include <fcntl.h>
  26 #include <signal.h>
  27 #include <sys/mman.h>
  28
  29 #if SANITIZER_FREEBSD
  30 // The MAP_NORESERVE define has been removed in FreeBSD 11.x, and even before
  31 // that, it was never implemented.  So just define it to zero.
  32 #undef  MAP_NORESERVE
  33 #define MAP_NORESERVE 0
  34 #endif
  35
  36 namespace __sanitizer {
  37
  38 // ------------- sanitizer_common.h
  39 uptr GetMmapGranularity() {
  40   return GetPageSize();
  41 }
  42
  43 void *MmapOrDie(uptr size, const char *mem_type, bool raw_report) {
  44   size = RoundUpTo(size, GetPageSizeCached());
  45   uptr res = internal_mmap(nullptr, size,
  46                            PROT_READ | PROT_WRITE,
  47                            MAP_PRIVATE | MAP_ANON, -1, 0);
  48   int reserrno;
  49   if (UNLIKELY(internal_iserror(res, &reserrno)))
  50     ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno, raw_report);
  51   IncreaseTotalMmap(size);
  52   return (void *)res;
  53 }
  54
  55 void UnmapOrDie(void *addr, uptr size) {
  56   if (!addr || !size) return;
  57   uptr res = internal_munmap(addr, size);
  58   if (UNLIKELY(internal_iserror(res))) {
  59     Report("ERROR: %s failed to deallocate 0x%zx (%zd) bytes at address %p\n",
  60            SanitizerToolName, size, size, addr);
  61     CHECK("unable to unmap" && 0);
  62   }
  63   DecreaseTotalMmap(size);
  64 }
  65
  66 void *MmapOrDieOnFatalError(uptr size, const char *mem_type) {
  67   size = RoundUpTo(size, GetPageSizeCached());
  68   uptr res = internal_mmap(nullptr, size,
  69                            PROT_READ | PROT_WRITE,
  70                            MAP_PRIVATE | MAP_ANON, -1, 0);
  71   int reserrno;
  72   if (UNLIKELY(internal_iserror(res, &reserrno))) {
  73     if (reserrno == ENOMEM)
  74       return nullptr;
  75     ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno);
  76   }
  77   IncreaseTotalMmap(size);
  78   return (void *)res;
  79 }
  80
  81 // We want to map a chunk of address space aligned to 'alignment'.
  82 // We do it by mapping a bit more and then unmapping redundant pieces.
  83 // We probably can do it with fewer syscalls in some OS-dependent way.
  84 void *MmapAlignedOrDieOnFatalError(uptr size, uptr alignment,
  85                                    const char *mem_type) {
  86   CHECK(IsPowerOfTwo(size));
  87   CHECK(IsPowerOfTwo(alignment));
  88   uptr map_size = size + alignment;
  89   uptr map_res = (uptr)MmapOrDieOnFatalError(map_size, mem_type);
  90   if (UNLIKELY(!map_res))
  91     return nullptr;
  92   uptr map_end = map_res + map_size;
  93   uptr res = map_res;
  94   if (!IsAligned(res, alignment)) {
  95     res = (map_res + alignment - 1) & ~(alignment - 1);
  96     UnmapOrDie((void*)map_res, res - map_res);
  97   }
  98   uptr end = res + size;
  99   if (end != map_end)
 100     UnmapOrDie((void*)end, map_end - end);
 101   return (void*)res;
 102 }
 103
 104 void *MmapNoReserveOrDie(uptr size, const char *mem_type) {
 105   uptr PageSize = GetPageSizeCached();
 106   uptr p = internal_mmap(nullptr,
 107                          RoundUpTo(size, PageSize),
 108                          PROT_READ | PROT_WRITE,
 109                          MAP_PRIVATE | MAP_ANON | MAP_NORESERVE,
 110                          -1, 0);
 111   int reserrno;
 112   if (UNLIKELY(internal_iserror(p, &reserrno)))
 113     ReportMmapFailureAndDie(size, mem_type, "allocate noreserve", reserrno);
 114   IncreaseTotalMmap(size);
 115   return (void *)p;
 116 }
 117
 118 void *MmapFixedImpl(uptr fixed_addr, uptr size, bool tolerate_enomem) {
 119   uptr PageSize = GetPageSizeCached();
 120   uptr p = internal_mmap((void*)(fixed_addr & ~(PageSize - 1)),
 121       RoundUpTo(size, PageSize),
 122       PROT_READ | PROT_WRITE,
 123       MAP_PRIVATE | MAP_ANON | MAP_FIXED,
 124       -1, 0);
 125   int reserrno;
 126   if (UNLIKELY(internal_iserror(p, &reserrno))) {
 127     if (tolerate_enomem && reserrno == ENOMEM)
 128       return nullptr;
 129     char mem_type[40];
 130     internal_snprintf(mem_type, sizeof(mem_type), "memory at address 0x%zx",
 131                       fixed_addr);
 132     ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno);
 133   }
 134   IncreaseTotalMmap(size);
 135   return (void *)p;
 136 }
 137
 138 void *MmapFixedOrDie(uptr fixed_addr, uptr size) {
 139   return MmapFixedImpl(fixed_addr, size, false /*tolerate_enomem*/);
 140 }
 141
 142 void *MmapFixedOrDieOnFatalError(uptr fixed_addr, uptr size) {
 143   return MmapFixedImpl(fixed_addr, size, true /*tolerate_enomem*/);
 144 }
 145
 146 bool MprotectNoAccess(uptr addr, uptr size) {
 147   return 0 == internal_mprotect((void*)addr, size, PROT_NONE);
 148 }
 149
 150 bool MprotectReadOnly(uptr addr, uptr size) {
 151   return 0 == internal_mprotect((void *)addr, size, PROT_READ);
 152 }
 153
 154 fd_t OpenFile(const char *filename, FileAccessMode mode, error_t *errno_p) {
 155   int flags;
 156   switch (mode) {
 157     case RdOnly: flags = O_RDONLY; break;
 158     case WrOnly: flags = O_WRONLY | O_CREAT; break;
 159     case RdWr: flags = O_RDWR | O_CREAT; break;
 160   }
 161   fd_t res = internal_open(filename, flags, 0660);
 162   if (internal_iserror(res, errno_p))
 163     return kInvalidFd;
 164   return res;
 165 }
 166
 167 void CloseFile(fd_t fd) {
 168   internal_close(fd);
 169 }
 170
 171 bool ReadFromFile(fd_t fd, void *buff, uptr buff_size, uptr *bytes_read,
 172                   error_t *error_p) {
 173   uptr res = internal_read(fd, buff, buff_size);
 174   if (internal_iserror(res, error_p))
 175     return false;
 176   if (bytes_read)
 177     *bytes_read = res;
 178   return true;
 179 }
 180
 181 bool WriteToFile(fd_t fd, const void *buff, uptr buff_size, uptr *bytes_written,
 182                  error_t *error_p) {
 183   uptr res = internal_write(fd, buff, buff_size);
 184   if (internal_iserror(res, error_p))
 185     return false;
 186   if (bytes_written)
 187     *bytes_written = res;
 188   return true;
 189 }
 190
 191 bool RenameFile(const char *oldpath, const char *newpath, error_t *error_p) {
 192   uptr res = internal_rename(oldpath, newpath);
 193   return !internal_iserror(res, error_p);
 194 }
 195
 196 void *MapFileToMemory(const char *file_name, uptr *buff_size) {
 197   fd_t fd = OpenFile(file_name, RdOnly);
 198   CHECK(fd != kInvalidFd);
 199   uptr fsize = internal_filesize(fd);
 200   CHECK_NE(fsize, (uptr)-1);
 201   CHECK_GT(fsize, 0);
 202   *buff_size = RoundUpTo(fsize, GetPageSizeCached());
 203   uptr map = internal_mmap(nullptr, *buff_size, PROT_READ, MAP_PRIVATE, fd, 0);
 204   return internal_iserror(map) ? nullptr : (void *)map;
 205 }
 206
 207 void *MapWritableFileToMemory(void *addr, uptr size, fd_t fd, OFF_T offset) {
 208   uptr flags = MAP_SHARED;
 209   if (addr) flags |= MAP_FIXED;
 210   uptr p = internal_mmap(addr, size, PROT_READ | PROT_WRITE, flags, fd, offset);
 211   int mmap_errno = 0;
 212   if (internal_iserror(p, &mmap_errno)) {
 213     Printf("could not map writable file (%d, %lld, %zu): %zd, errno: %d\n",
 214            fd, (long long)offset, size, p, mmap_errno);
 215     return nullptr;
 216   }
 217   return (void *)p;
 218 }
 219
 220 static inline bool IntervalsAreSeparate(uptr start1, uptr end1,
 221                                         uptr start2, uptr end2) {
 222   CHECK(start1 <= end1);
 223   CHECK(start2 <= end2);
 224   return (end1 < start2) || (end2 < start1);
 225 }
 226
 227 // FIXME: this is thread-unsafe, but should not cause problems most of the time.
 228 // When the shadow is mapped only a single thread usually exists (plus maybe
 229 // several worker threads on Mac, which aren't expected to map big chunks of
 230 // memory).
 231 bool MemoryRangeIsAvailable(uptr range_start, uptr range_end) {
 232   MemoryMappingLayout proc_maps(/*cache_enabled*/true);
 233   MemoryMappedSegment segment;
 234   while (proc_maps.Next(&segment)) {
 235     if (segment.start == segment.end) continue;  // Empty range.
 236     CHECK_NE(0, segment.end);
 237     if (!IntervalsAreSeparate(segment.start, segment.end - 1, range_start,
 238                               range_end))
 239       return false;
 240   }
 241   return true;
 242 }
 243
 244 void DumpProcessMap() {
 245   MemoryMappingLayout proc_maps(/*cache_enabled*/true);
 246   const sptr kBufSize = 4095;
 247   char *filename = (char*)MmapOrDie(kBufSize, __func__);
 248   MemoryMappedSegment segment(filename, kBufSize);
 249   Report("Process memory map follows:\n");
 250   while (proc_maps.Next(&segment)) {
 251     Printf("\t%p-%p\t%s\n", (void *)segment.start, (void *)segment.end,
 252            segment.filename);
 253   }
 254   Report("End of process memory map.\n");
 255   UnmapOrDie(filename, kBufSize);
 256 }
 257
 258 const char *GetPwd() {
 259   return GetEnv("PWD");
 260 }
 261
 262 bool IsPathSeparator(const char c) {
 263   return c == '/';
 264 }
 265
 266 bool IsAbsolutePath(const char *path) {
 267   return path != nullptr && IsPathSeparator(path[0]);
 268 }
 269
 270 void ReportFile::Write(const char *buffer, uptr length) {
 271   SpinMutexLock l(mu);
 272   static const char *kWriteError =
 273       "ReportFile::Write() can't output requested buffer!\n";
 274   ReopenIfNecessary();
 275   if (length != internal_write(fd, buffer, length)) {
 276     internal_write(fd, kWriteError, internal_strlen(kWriteError));
 277     Die();
 278   }
 279 }
 280
 281 bool GetCodeRangeForFile(const char *module, uptr *start, uptr *end) {
 282   MemoryMappingLayout proc_maps(/*cache_enabled*/false);
 283   InternalScopedString buff(kMaxPathLength);
 284   MemoryMappedSegment segment(buff.data(), kMaxPathLength);
 285   while (proc_maps.Next(&segment)) {
 286     if (segment.IsExecutable() &&
 287         internal_strcmp(module, segment.filename) == 0) {
 288       *start = segment.start;
 289       *end = segment.end;
 290       return true;
 291     }
 292   }
 293   return false;
 294 }
 295
 296 uptr SignalContext::GetAddress() const {
 297   auto si = static_cast<const siginfo_t *>(siginfo);
 298   return (uptr)si->si_addr;
 299 }
 300
 301 bool SignalContext::IsMemoryAccess() const {
 302   auto si = static_cast<const siginfo_t *>(siginfo);
 303   return si->si_signo == SIGSEGV;
 304 }
 305
 306 int SignalContext::GetType() const {
 307   return static_cast<const siginfo_t *>(siginfo)->si_signo;
 308 }
 309
 310 const char *SignalContext::Describe() const {
 311   switch (GetType()) {
 312     case SIGFPE:
 313       return "FPE";
 314     case SIGILL:
 315       return "ILL";
 316     case SIGABRT:
 317       return "ABRT";
 318     case SIGSEGV:
 319       return "SEGV";
 320     case SIGBUS:
 321       return "BUS";
 322   }
 323   return "UNKNOWN SIGNAL";
 324 }
 325
 326 } // namespace __sanitizer
 327
 328 #endif // SANITIZER_POSIX