libsanitizer/sanitizer_common/sanitizer_procmaps_fuchsia.cpp

   1 //===-- sanitizer_procmaps_fuchsia.cpp
   2 //----------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // Information about the process mappings (Fuchsia-specific parts).
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "sanitizer_platform.h"
  14 #if SANITIZER_FUCHSIA
  15 #include <zircon/process.h>
  16 #include <zircon/syscalls.h>
  17
  18 #include "sanitizer_common.h"
  19 #include "sanitizer_procmaps.h"
  20
  21 namespace __sanitizer {
  22
  23 // The cache flag is ignored on Fuchsia because a process can always get this
  24 // information via its process-self handle.
  25 MemoryMappingLayout::MemoryMappingLayout(bool) { Reset(); }
  26
  27 void MemoryMappingLayout::Reset() {
  28   data_.data.clear();
  29   data_.current = 0;
  30
  31   size_t count;
  32   zx_status_t status = _zx_object_get_info(
  33       _zx_process_self(), ZX_INFO_PROCESS_MAPS, nullptr, 0, nullptr, &count);
  34   if (status != ZX_OK) {
  35     return;
  36   }
  37
  38   size_t filled;
  39   do {
  40     data_.data.resize(count);
  41     status = _zx_object_get_info(
  42         _zx_process_self(), ZX_INFO_PROCESS_MAPS, data_.data.data(),
  43         count * sizeof(zx_info_maps_t), &filled, &count);
  44     if (status != ZX_OK) {
  45       data_.data.clear();
  46       return;
  47     }
  48   } while (filled < count);
  49 }
  50
  51 MemoryMappingLayout::~MemoryMappingLayout() {}
  52
  53 bool MemoryMappingLayout::Error() const { return data_.data.empty(); }
  54
  55 bool MemoryMappingLayout::Next(MemoryMappedSegment *segment) {
  56   while (data_.current < data_.data.size()) {
  57     const auto &entry = data_.data[data_.current++];
  58     if (entry.type == ZX_INFO_MAPS_TYPE_MAPPING) {
  59       segment->start = entry.base;
  60       segment->end = entry.base + entry.size;
  61       segment->offset = entry.u.mapping.vmo_offset;
  62       const auto flags = entry.u.mapping.mmu_flags;
  63       segment->protection =
  64           ((flags & ZX_VM_PERM_READ) ? kProtectionRead : 0) |
  65           ((flags & ZX_VM_PERM_WRITE) ? kProtectionWrite : 0) |
  66           ((flags & ZX_VM_PERM_EXECUTE) ? kProtectionExecute : 0);
  67       if (segment->filename && segment->filename_size > 0) {
  68         uptr len = Min(sizeof(entry.name), segment->filename_size) - 1;
  69         internal_strncpy(segment->filename, entry.name, len);
  70         segment->filename[len] = 0;
  71       }
  72       return true;
  73     }
  74   }
  75   return false;
  76 }
  77
  78 }  // namespace __sanitizer
  79
  80 #endif  // SANITIZER_FUCHSIA