Method CheckMap

Bcore/src/main/cpp/dex/dex_file_verifier.cc:443–552

}

bool DexFileVerifier::CheckMap() {
  const DexFile::MapList* map = reinterpret_cast<const DexFile::MapList*>(begin_ +
                                                                          header_->map_off_);
  // Check that map list content is available.
  if (!CheckListSize(map, 1, sizeof(DexFile::MapList), "maplist content")) {
    return false;
  }

  const DexFile::MapItem* item = map->list_;

  uint32_t count = map->size_;
  uint32_t last_offset = 0;
  uint32_t last_type = 0;
  uint32_t data_item_count = 0;
  uint32_t data_items_left = header_->data_size_;
  uint32_t used_bits = 0;

  // Sanity check the size of the map list.
  if (!CheckListSize(item, count, sizeof(DexFile::MapItem), "map size")) {
    return false;
  }

  // Check the items listed in the map.
  for (uint32_t i = 0; i < count; i++) {
    if (UNLIKELY(last_offset >= item->offset_ && i != 0)) {
      ErrorStringPrintf("Out of order map item: %x then %x for type %x last type was %x",
                        last_offset,
                        item->offset_,
                        static_cast<uint32_t>(item->type_),
                        last_type);
      return false;
    }
    if (UNLIKELY(item->offset_ >= header_->file_size_)) {
      ErrorStringPrintf("Map item after end of file: %x, size %x",
                        item->offset_, header_->file_size_);
      return false;
    }

    DexFile::MapItemType item_type = static_cast<DexFile::MapItemType>(item->type_);
    if (IsDataSectionType(item_type)) {
      uint32_t icount = item->size_;
      if (UNLIKELY(icount > data_items_left)) {
        ErrorStringPrintf("Too many items in data section: %ud item_type %zx",
                          data_item_count + icount,
                          static_cast<size_t>(item_type));
        return false;
      }
      data_items_left -= icount;
      data_item_count += icount;
    }

    uint32_t bit = MapTypeToBitMask(item_type);

    if (UNLIKELY(bit == 0)) {
      ErrorStringPrintf("Unknown map section type %x", item->type_);
      return false;
    }