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_libc.h.
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "sanitizer_platform.h"
  14 #if SANITIZER_LINUX || SANITIZER_MAC
  15
  16 #include "sanitizer_common.h"
  17 #include "sanitizer_libc.h"
  18 #include "sanitizer_procmaps.h"
  19 #include "sanitizer_stacktrace.h"
  20
  21 #include <sys/mman.h>
  22
  23 namespace __sanitizer {
  24
  25 // ------------- sanitizer_common.h
  26 uptr GetMmapGranularity() {
  27   return GetPageSize();
  28 }
  29
  30 uptr GetMaxVirtualAddress() {
  31 #if SANITIZER_WORDSIZE == 64
  32 # if defined(__powerpc64__)
  33   // On PowerPC64 we have two different address space layouts: 44- and 46-bit.
  34   // We somehow need to figure our which one we are using now and choose
  35   // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL.
  36   // Note that with 'ulimit -s unlimited' the stack is moved away from the top
  37   // of the address space, so simply checking the stack address is not enough.
  38   return (1ULL << 44) - 1;  // 0x00000fffffffffffUL
  39 # else
  40   return (1ULL << 47) - 1;  // 0x00007fffffffffffUL;
  41 # endif
  42 #else  // SANITIZER_WORDSIZE == 32
  43   // FIXME: We can probably lower this on Android?
  44   return (1ULL << 32) - 1;  // 0xffffffff;
  45 #endif  // SANITIZER_WORDSIZE
  46 }
  47
  48 void *MmapOrDie(uptr size, const char *mem_type) {
  49   size = RoundUpTo(size, GetPageSizeCached());
  50   uptr res = internal_mmap(0, size,
  51                             PROT_READ | PROT_WRITE,
  52                             MAP_PRIVATE | MAP_ANON, -1, 0);
  53   int reserrno;
  54   if (internal_iserror(res, &reserrno)) {
  55     static int recursion_count;
  56     if (recursion_count) {
  57       // The Report() and CHECK calls below may call mmap recursively and fail.
  58       // If we went into recursion, just die.
  59       RawWrite("ERROR: Failed to mmap\n");
  60       Die();
  61     }
  62     recursion_count++;
  63     Report("ERROR: %s failed to allocate 0x%zx (%zd) bytes of %s: %d\n",
  64            SanitizerToolName, size, size, mem_type, reserrno);
  65     DumpProcessMap();
  66     CHECK("unable to mmap" && 0);
  67   }
  68   return (void *)res;
  69 }
  70
  71 void UnmapOrDie(void *addr, uptr size) {
  72   if (!addr || !size) return;
  73   uptr res = internal_munmap(addr, size);
  74   if (internal_iserror(res)) {
  75     Report("ERROR: %s failed to deallocate 0x%zx (%zd) bytes at address %p\n",
  76            SanitizerToolName, size, size, addr);
  77     CHECK("unable to unmap" && 0);
  78   }
  79 }
  80
  81 void *MmapFixedNoReserve(uptr fixed_addr, uptr size) {
  82   uptr PageSize = GetPageSizeCached();
  83   uptr p = internal_mmap((void*)(fixed_addr & ~(PageSize - 1)),
  84       RoundUpTo(size, PageSize),
  85       PROT_READ | PROT_WRITE,
  86       MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE,
  87       -1, 0);
  88   int reserrno;
  89   if (internal_iserror(p, &reserrno))
  90     Report("ERROR: "
  91            "%s failed to allocate 0x%zx (%zd) bytes at address %p (%d)\n",
  92            SanitizerToolName, size, size, fixed_addr, reserrno);
  93   return (void *)p;
  94 }
  95
  96 void *MmapFixedOrDie(uptr fixed_addr, uptr size) {
  97   uptr PageSize = GetPageSizeCached();
  98   uptr p = internal_mmap((void*)(fixed_addr & ~(PageSize - 1)),
  99       RoundUpTo(size, PageSize),
 100       PROT_READ | PROT_WRITE,
 101       MAP_PRIVATE | MAP_ANON | MAP_FIXED,
 102       -1, 0);
 103   int reserrno;
 104   if (internal_iserror(p, &reserrno)) {
 105     Report("ERROR:"
 106            " %s failed to allocate 0x%zx (%zd) bytes at address %p (%d)\n",
 107            SanitizerToolName, size, size, fixed_addr, reserrno);
 108     CHECK("unable to mmap" && 0);
 109   }
 110   return (void *)p;
 111 }
 112
 113 void *Mprotect(uptr fixed_addr, uptr size) {
 114   return (void *)internal_mmap((void*)fixed_addr, size,
 115                                PROT_NONE,
 116                                MAP_PRIVATE | MAP_ANON | MAP_FIXED |
 117                                MAP_NORESERVE, -1, 0);
 118 }
 119
 120 void *MapFileToMemory(const char *file_name, uptr *buff_size) {
 121   uptr openrv = OpenFile(file_name, false);
 122   CHECK(!internal_iserror(openrv));
 123   fd_t fd = openrv;
 124   uptr fsize = internal_filesize(fd);
 125   CHECK_NE(fsize, (uptr)-1);
 126   CHECK_GT(fsize, 0);
 127   *buff_size = RoundUpTo(fsize, GetPageSizeCached());
 128   uptr map = internal_mmap(0, *buff_size, PROT_READ, MAP_PRIVATE, fd, 0);
 129   return internal_iserror(map) ? 0 : (void *)map;
 130 }
 131
 132
 133 static inline bool IntervalsAreSeparate(uptr start1, uptr end1,
 134                                         uptr start2, uptr end2) {
 135   CHECK(start1 <= end1);
 136   CHECK(start2 <= end2);
 137   return (end1 < start2) || (end2 < start1);
 138 }
 139
 140 // FIXME: this is thread-unsafe, but should not cause problems most of the time.
 141 // When the shadow is mapped only a single thread usually exists (plus maybe
 142 // several worker threads on Mac, which aren't expected to map big chunks of
 143 // memory).
 144 bool MemoryRangeIsAvailable(uptr range_start, uptr range_end) {
 145   MemoryMappingLayout proc_maps(/*cache_enabled*/true);
 146   uptr start, end;
 147   while (proc_maps.Next(&start, &end,
 148                         /*offset*/0, /*filename*/0, /*filename_size*/0,
 149                         /*protection*/0)) {
 150     if (!IntervalsAreSeparate(start, end, range_start, range_end))
 151       return false;
 152   }
 153   return true;
 154 }
 155
 156 void DumpProcessMap() {
 157   MemoryMappingLayout proc_maps(/*cache_enabled*/true);
 158   uptr start, end;
 159   const sptr kBufSize = 4095;
 160   char *filename = (char*)MmapOrDie(kBufSize, __FUNCTION__);
 161   Report("Process memory map follows:\n");
 162   while (proc_maps.Next(&start, &end, /* file_offset */0,
 163                         filename, kBufSize, /* protection */0)) {
 164     Printf("\t%p-%p\t%s\n", (void*)start, (void*)end, filename);
 165   }
 166   Report("End of process memory map.\n");
 167   UnmapOrDie(filename, kBufSize);
 168 }
 169
 170 const char *GetPwd() {
 171   return GetEnv("PWD");
 172 }
 173
 174 char *FindPathToBinary(const char *name) {
 175   const char *path = GetEnv("PATH");
 176   if (!path)
 177     return 0;
 178   uptr name_len = internal_strlen(name);
 179   InternalScopedBuffer<char> buffer(kMaxPathLength);
 180   const char *beg = path;
 181   while (true) {
 182     const char *end = internal_strchrnul(beg, ':');
 183     uptr prefix_len = end - beg;
 184     if (prefix_len + name_len + 2 <= kMaxPathLength) {
 185       internal_memcpy(buffer.data(), beg, prefix_len);
 186       buffer[prefix_len] = '/';
 187       internal_memcpy(&buffer[prefix_len + 1], name, name_len);
 188       buffer[prefix_len + 1 + name_len] = '\0';
 189       if (FileExists(buffer.data()))
 190         return internal_strdup(buffer.data());
 191     }
 192     if (*end == '\0') break;
 193     beg = end + 1;
 194   }
 195   return 0;
 196 }
 197
 198 void MaybeOpenReportFile() {
 199   if (!log_to_file || (report_fd_pid == internal_getpid())) return;
 200   InternalScopedBuffer<char> report_path_full(4096);
 201   internal_snprintf(report_path_full.data(), report_path_full.size(),
 202                     "%s.%d", report_path_prefix, internal_getpid());
 203   uptr openrv = OpenFile(report_path_full.data(), true);
 204   if (internal_iserror(openrv)) {
 205     report_fd = kStderrFd;
 206     log_to_file = false;
 207     Report("ERROR: Can't open file: %s\n", report_path_full.data());
 208     Die();
 209   }
 210   if (report_fd != kInvalidFd) {
 211     // We're in the child. Close the parent's log.
 212     internal_close(report_fd);
 213   }
 214   report_fd = openrv;
 215   report_fd_pid = internal_getpid();
 216 }
 217
 218 void RawWrite(const char *buffer) {
 219   static const char *kRawWriteError =
 220       "RawWrite can't output requested buffer!\n";
 221   uptr length = (uptr)internal_strlen(buffer);
 222   MaybeOpenReportFile();
 223   if (length != internal_write(report_fd, buffer, length)) {
 224     internal_write(report_fd, kRawWriteError, internal_strlen(kRawWriteError));
 225     Die();
 226   }
 227 }
 228
 229 bool GetCodeRangeForFile(const char *module, uptr *start, uptr *end) {
 230   uptr s, e, off, prot;
 231   InternalMmapVector<char> fn(4096);
 232   fn.push_back(0);
 233   MemoryMappingLayout proc_maps(/*cache_enabled*/false);
 234   while (proc_maps.Next(&s, &e, &off, &fn[0], fn.capacity(), &prot)) {
 235     if ((prot & MemoryMappingLayout::kProtectionExecute) != 0
 236         && internal_strcmp(module, &fn[0]) == 0) {
 237       *start = s;
 238       *end = e;
 239       return true;
 240     }
 241   }
 242   return false;
 243 }
 244
 245 }  // namespace __sanitizer
 246
 247 #endif  // SANITIZER_LINUX || SANITIZER_MAC