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
  23 #include <errno.h>
  24 #include <fcntl.h>
  25 #include <signal.h>
  26 #include <sys/mman.h>
  27
  28 #if SANITIZER_FREEBSD
  29 // The MAP_NORESERVE define has been removed in FreeBSD 11.x, and even before
  30 // that, it was never implemented.  So just define it to zero.
  31 #undef  MAP_NORESERVE
  32 #define MAP_NORESERVE 0
  33 #endif
  34
  35 namespace __sanitizer {
  36
  37 // ------------- sanitizer_common.h
  38 uptr GetMmapGranularity() {
  39   return GetPageSize();
  40 }
  41
  42 void *MmapOrDie(uptr size, const char *mem_type, bool raw_report) {
  43   size = RoundUpTo(size, GetPageSizeCached());
  44   uptr res = internal_mmap(nullptr, size,
  45                            PROT_READ | PROT_WRITE,
  46                            MAP_PRIVATE | MAP_ANON, -1, 0);
  47   int reserrno;
  48   if (UNLIKELY(internal_iserror(res, &reserrno)))
  49     ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno, raw_report);
  50   IncreaseTotalMmap(size);
  51   return (void *)res;
  52 }
  53
  54 void UnmapOrDie(void *addr, uptr size) {
  55   if (!addr || !size) return;
  56   uptr res = internal_munmap(addr, size);
  57   if (UNLIKELY(internal_iserror(res))) {
  58     Report("ERROR: %s failed to deallocate 0x%zx (%zd) bytes at address %p\n",
  59            SanitizerToolName, size, size, addr);
  60     CHECK("unable to unmap" && 0);
  61   }
  62   DecreaseTotalMmap(size);
  63 }
  64
  65 void *MmapOrDieOnFatalError(uptr size, const char *mem_type) {
  66   size = RoundUpTo(size, GetPageSizeCached());
  67   uptr res = internal_mmap(nullptr, size,
  68                            PROT_READ | PROT_WRITE,
  69                            MAP_PRIVATE | MAP_ANON, -1, 0);
  70   int reserrno;
  71   if (UNLIKELY(internal_iserror(res, &reserrno))) {
  72     if (reserrno == ENOMEM)
  73       return nullptr;
  74     ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno);
  75   }
  76   IncreaseTotalMmap(size);
  77   return (void *)res;
  78 }
  79
  80 // We want to map a chunk of address space aligned to 'alignment'.
  81 // We do it by mapping a bit more and then unmapping redundant pieces.
  82 // We probably can do it with fewer syscalls in some OS-dependent way.
  83 void *MmapAlignedOrDieOnFatalError(uptr size, uptr alignment,
  84                                    const char *mem_type) {
  85   CHECK(IsPowerOfTwo(size));
  86   CHECK(IsPowerOfTwo(alignment));
  87   uptr map_size = size + alignment;
  88   uptr map_res = (uptr)MmapOrDieOnFatalError(map_size, mem_type);
  89   if (UNLIKELY(!map_res))
  90     return nullptr;
  91   uptr map_end = map_res + map_size;
  92   uptr res = map_res;
  93   if (!IsAligned(res, alignment)) {
  94     res = (map_res + alignment - 1) & ~(alignment - 1);
  95     UnmapOrDie((void*)map_res, res - map_res);
  96   }
  97   uptr end = res + size;
  98   if (end != map_end)
  99     UnmapOrDie((void*)end, map_end - end);
 100   return (void*)res;
 101 }
 102
 103 void *MmapNoReserveOrDie(uptr size, const char *mem_type) {
 104   uptr PageSize = GetPageSizeCached();
 105   uptr p = internal_mmap(nullptr,
 106                          RoundUpTo(size, PageSize),
 107                          PROT_READ | PROT_WRITE,
 108                          MAP_PRIVATE | MAP_ANON | MAP_NORESERVE,
 109                          -1, 0);
 110   int reserrno;
 111   if (UNLIKELY(internal_iserror(p, &reserrno)))
 112     ReportMmapFailureAndDie(size, mem_type, "allocate noreserve", reserrno);
 113   IncreaseTotalMmap(size);
 114   return (void *)p;
 115 }
 116
 117 void *MmapFixedImpl(uptr fixed_addr, uptr size, bool tolerate_enomem) {
 118   uptr PageSize = GetPageSizeCached();
 119   uptr p = internal_mmap((void*)(fixed_addr & ~(PageSize - 1)),
 120       RoundUpTo(size, PageSize),
 121       PROT_READ | PROT_WRITE,
 122       MAP_PRIVATE | MAP_ANON | MAP_FIXED,
 123       -1, 0);
 124   int reserrno;
 125   if (UNLIKELY(internal_iserror(p, &reserrno))) {
 126     if (tolerate_enomem && reserrno == ENOMEM)
 127       return nullptr;
 128     char mem_type[40];
 129     internal_snprintf(mem_type, sizeof(mem_type), "memory at address 0x%zx",
 130                       fixed_addr);
 131     ReportMmapFailureAndDie(size, mem_type, "allocate", reserrno);
 132   }
 133   IncreaseTotalMmap(size);
 134   return (void *)p;
 135 }
 136
 137 void *MmapFixedOrDie(uptr fixed_addr, uptr size) {
 138   return MmapFixedImpl(fixed_addr, size, false /*tolerate_enomem*/);
 139 }
 140
 141 void *MmapFixedOrDieOnFatalError(uptr fixed_addr, uptr size) {
 142   return MmapFixedImpl(fixed_addr, size, true /*tolerate_enomem*/);
 143 }
 144
 145 bool MprotectNoAccess(uptr addr, uptr size) {
 146   return 0 == internal_mprotect((void*)addr, size, PROT_NONE);
 147 }
 148
 149 bool MprotectReadOnly(uptr addr, uptr size) {
 150   return 0 == internal_mprotect((void *)addr, size, PROT_READ);
 151 }
 152
 153 #if !SANITIZER_MAC
 154 void MprotectMallocZones(void *addr, int prot) {}
 155 #endif
 156
 157 fd_t OpenFile(const char *filename, FileAccessMode mode, error_t *errno_p) {
 158   int flags;
 159   switch (mode) {
 160     case RdOnly: flags = O_RDONLY; break;
 161     case WrOnly: flags = O_WRONLY | O_CREAT | O_TRUNC; break;
 162     case RdWr: flags = O_RDWR | O_CREAT; break;
 163   }
 164   fd_t res = internal_open(filename, flags, 0660);
 165   if (internal_iserror(res, errno_p))
 166     return kInvalidFd;
 167   return res;
 168 }
 169
 170 void CloseFile(fd_t fd) {
 171   internal_close(fd);
 172 }
 173
 174 bool ReadFromFile(fd_t fd, void *buff, uptr buff_size, uptr *bytes_read,
 175                   error_t *error_p) {
 176   uptr res = internal_read(fd, buff, buff_size);
 177   if (internal_iserror(res, error_p))
 178     return false;
 179   if (bytes_read)
 180     *bytes_read = res;
 181   return true;
 182 }
 183
 184 bool WriteToFile(fd_t fd, const void *buff, uptr buff_size, uptr *bytes_written,
 185                  error_t *error_p) {
 186   uptr res = internal_write(fd, buff, buff_size);
 187   if (internal_iserror(res, error_p))
 188     return false;
 189   if (bytes_written)
 190     *bytes_written = res;
 191   return true;
 192 }
 193
 194 bool RenameFile(const char *oldpath, const char *newpath, error_t *error_p) {
 195   uptr res = internal_rename(oldpath, newpath);
 196   return !internal_iserror(res, error_p);
 197 }
 198
 199 void *MapFileToMemory(const char *file_name, uptr *buff_size) {
 200   fd_t fd = OpenFile(file_name, RdOnly);
 201   CHECK(fd != kInvalidFd);
 202   uptr fsize = internal_filesize(fd);
 203   CHECK_NE(fsize, (uptr)-1);
 204   CHECK_GT(fsize, 0);
 205   *buff_size = RoundUpTo(fsize, GetPageSizeCached());
 206   uptr map = internal_mmap(nullptr, *buff_size, PROT_READ, MAP_PRIVATE, fd, 0);
 207   return internal_iserror(map) ? nullptr : (void *)map;
 208 }
 209
 210 void *MapWritableFileToMemory(void *addr, uptr size, fd_t fd, OFF_T offset) {
 211   uptr flags = MAP_SHARED;
 212   if (addr) flags |= MAP_FIXED;
 213   uptr p = internal_mmap(addr, size, PROT_READ | PROT_WRITE, flags, fd, offset);
 214   int mmap_errno = 0;
 215   if (internal_iserror(p, &mmap_errno)) {
 216     Printf("could not map writable file (%d, %lld, %zu): %zd, errno: %d\n",
 217            fd, (long long)offset, size, p, mmap_errno);
 218     return nullptr;
 219   }
 220   return (void *)p;
 221 }
 222
 223 static inline bool IntervalsAreSeparate(uptr start1, uptr end1,
 224                                         uptr start2, uptr end2) {
 225   CHECK(start1 <= end1);
 226   CHECK(start2 <= end2);
 227   return (end1 < start2) || (end2 < start1);
 228 }
 229
 230 // FIXME: this is thread-unsafe, but should not cause problems most of the time.
 231 // When the shadow is mapped only a single thread usually exists (plus maybe
 232 // several worker threads on Mac, which aren't expected to map big chunks of
 233 // memory).
 234 bool MemoryRangeIsAvailable(uptr range_start, uptr range_end) {
 235   MemoryMappingLayout proc_maps(/*cache_enabled*/true);
 236   MemoryMappedSegment segment;
 237   while (proc_maps.Next(&segment)) {
 238     if (segment.start == segment.end) continue;  // Empty range.
 239     CHECK_NE(0, segment.end);
 240     if (!IntervalsAreSeparate(segment.start, segment.end - 1, range_start,
 241                               range_end))
 242       return false;
 243   }
 244   return true;
 245 }
 246
 247 void DumpProcessMap() {
 248   MemoryMappingLayout proc_maps(/*cache_enabled*/true);
 249   const sptr kBufSize = 4095;
 250   char *filename = (char*)MmapOrDie(kBufSize, __func__);
 251   MemoryMappedSegment segment(filename, kBufSize);
 252   Report("Process memory map follows:\n");
 253   while (proc_maps.Next(&segment)) {
 254     Printf("\t%p-%p\t%s\n", (void *)segment.start, (void *)segment.end,
 255            segment.filename);
 256   }
 257   Report("End of process memory map.\n");
 258   UnmapOrDie(filename, kBufSize);
 259 }
 260
 261 const char *GetPwd() {
 262   return GetEnv("PWD");
 263 }
 264
 265 bool IsPathSeparator(const char c) {
 266   return c == '/';
 267 }
 268
 269 bool IsAbsolutePath(const char *path) {
 270   return path != nullptr && IsPathSeparator(path[0]);
 271 }
 272
 273 void ReportFile::Write(const char *buffer, uptr length) {
 274   SpinMutexLock l(mu);
 275   static const char *kWriteError =
 276       "ReportFile::Write() can't output requested buffer!\n";
 277   ReopenIfNecessary();
 278   if (length != internal_write(fd, buffer, length)) {
 279     internal_write(fd, kWriteError, internal_strlen(kWriteError));
 280     Die();
 281   }
 282 }
 283
 284 bool GetCodeRangeForFile(const char *module, uptr *start, uptr *end) {
 285   MemoryMappingLayout proc_maps(/*cache_enabled*/false);
 286   InternalScopedString buff(kMaxPathLength);
 287   MemoryMappedSegment segment(buff.data(), kMaxPathLength);
 288   while (proc_maps.Next(&segment)) {
 289     if (segment.IsExecutable() &&
 290         internal_strcmp(module, segment.filename) == 0) {
 291       *start = segment.start;
 292       *end = segment.end;
 293       return true;
 294     }
 295   }
 296   return false;
 297 }
 298
 299 uptr SignalContext::GetAddress() const {
 300   auto si = static_cast<const siginfo_t *>(siginfo);
 301   return (uptr)si->si_addr;
 302 }
 303
 304 bool SignalContext::IsMemoryAccess() const {
 305   auto si = static_cast<const siginfo_t *>(siginfo);
 306   return si->si_signo == SIGSEGV;
 307 }
 308
 309 int SignalContext::GetType() const {
 310   return static_cast<const siginfo_t *>(siginfo)->si_signo;
 311 }
 312
 313 const char *SignalContext::Describe() const {
 314   switch (GetType()) {
 315     case SIGFPE:
 316       return "FPE";
 317     case SIGILL:
 318       return "ILL";
 319     case SIGABRT:
 320       return "ABRT";
 321     case SIGSEGV:
 322       return "SEGV";
 323     case SIGBUS:
 324       return "BUS";
 325   }
 326   return "UNKNOWN SIGNAL";
 327 }
 328
 329 } // namespace __sanitizer
 330
 331 #endif // SANITIZER_POSIX