ce1c49da6f
Memory mapping the central directory of specific APKs caused memory mappings to build up over time because they were never unmapped correctly. This is because MappedFile is not calling munmap with the size of the data after aligning the mmap offset to a page boundary. Bug: 133463863 Test: install APKs and verify that the entire mapped CD is unmaped Test: ran aapt2 as daemon and confirmed that mapped CD is unmapped Change-Id: I26bda27c83615d1a166d92e43a2327909c453b89
90 lines
2.8 KiB
C++
90 lines
2.8 KiB
C++
/*
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* Copyright (C) 2018 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include "android-base/mapped_file.h"
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#include <errno.h>
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#include "android-base/unique_fd.h"
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namespace android {
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namespace base {
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static off64_t InitPageSize() {
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#if defined(_WIN32)
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SYSTEM_INFO si;
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GetSystemInfo(&si);
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return si.dwAllocationGranularity;
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#else
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return sysconf(_SC_PAGE_SIZE);
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#endif
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}
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std::unique_ptr<MappedFile> MappedFile::FromFd(borrowed_fd fd, off64_t offset, size_t length,
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int prot) {
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static off64_t page_size = InitPageSize();
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size_t slop = offset % page_size;
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off64_t file_offset = offset - slop;
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off64_t file_length = length + slop;
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#if defined(_WIN32)
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HANDLE handle =
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CreateFileMapping(reinterpret_cast<HANDLE>(_get_osfhandle(fd.get())), nullptr,
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(prot & PROT_WRITE) ? PAGE_READWRITE : PAGE_READONLY, 0, 0, nullptr);
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if (handle == nullptr) {
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// http://b/119818070 "app crashes when reading asset of zero length".
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// Return a MappedFile that's only valid for reading the size.
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if (length == 0) {
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return std::unique_ptr<MappedFile>(new MappedFile{nullptr, 0, 0, nullptr});
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}
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return nullptr;
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}
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void* base = MapViewOfFile(handle, (prot & PROT_WRITE) ? FILE_MAP_ALL_ACCESS : FILE_MAP_READ, 0,
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file_offset, file_length);
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if (base == nullptr) {
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CloseHandle(handle);
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return nullptr;
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}
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return std::unique_ptr<MappedFile>(
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new MappedFile{static_cast<char*>(base), length, slop, handle});
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#else
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void* base = mmap(nullptr, file_length, prot, MAP_SHARED, fd.get(), file_offset);
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if (base == MAP_FAILED) {
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// http://b/119818070 "app crashes when reading asset of zero length".
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// mmap fails with EINVAL for a zero length region.
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if (errno == EINVAL && length == 0) {
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return std::unique_ptr<MappedFile>(new MappedFile{nullptr, 0, 0});
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}
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return nullptr;
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}
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return std::unique_ptr<MappedFile>(new MappedFile{static_cast<char*>(base), length, slop});
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#endif
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}
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MappedFile::~MappedFile() {
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#if defined(_WIN32)
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if (base_ != nullptr) UnmapViewOfFile(base_);
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if (handle_ != nullptr) CloseHandle(handle_);
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#else
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if (base_ != nullptr) munmap(base_, size_ + offset_);
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#endif
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base_ = nullptr;
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offset_ = size_ = 0;
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}
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} // namespace base
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} // namespace android
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