Merge "imgdiff: Fix an edge case that leads to infinite loop." (3b828d87) · Commits · e / tools / etwrp

applypatch/Android.mk

+1 −0

Original line number	Diff line number	Diff line
		@@ -124,6 +124,7 @@ libimgdiff_cflags := \

		libimgdiff_static_libraries := \
		libbsdiff \
		libbase \
		libz

		# libimgdiff (static library)

applypatch/imgdiff.cpp

+10 −15

Original line number	Diff line number	Diff line
		@@ -124,6 +124,7 @@
		#include "applypatch/imgdiff.h"

		#include <errno.h>
		#include <fcntl.h>
		#include <stdio.h>
		#include <stdlib.h>
		#include <string.h>
		@@ -131,6 +132,9 @@
		#include <sys/types.h>
		#include <unistd.h>

		#include <android-base/file.h>
		#include <android-base/unique_fd.h>

		#include <bsdiff.h>
		#include <zlib.h>

		@@ -382,19 +386,12 @@ unsigned char* ReadImage(const char* filename, int* num_chunks, ImageChunk** chu
		}

		size_t sz = static_cast<size_t>(st.st_size);
		unsigned char* img = static_cast<unsigned char*>(malloc(sz + 4));
		FILE* f = fopen(filename, "rb");
		if (fread(img, 1, sz, f) != sz) {
		unsigned char* img = static_cast<unsigned char*>(malloc(sz));
		android::base::unique_fd fd(open(filename, O_RDONLY));
		if (!android::base::ReadFully(fd, img, sz)) {
		printf("failed to read \"%s\" %s\n", filename, strerror(errno));
		fclose(f);
		return NULL;
		return nullptr;
		}
		fclose(f);

		// append 4 zero bytes to the data so we can always search for the
		// four-byte string 1f8b0800 starting at any point in the actual
		// file data, without special-casing the end of the data.
		memset(img+sz, 0, 4);

		size_t pos = 0;

		@@ -518,10 +515,8 @@ unsigned char* ReadImage(const char* filename, int* num_chunks, ImageChunk** chu
		curr->data = p;

		for (curr->len = 0; curr->len < (sz - pos); ++curr->len) {
		if (p[curr->len] == 0x1f &&
		p[curr->len+1] == 0x8b &&
		p[curr->len+2] == 0x08 &&
		p[curr->len+3] == 0x00) {
		if (sz - pos >= 4 && p[curr->len] == 0x1f && p[curr->len + 1] == 0x8b &&
		p[curr->len + 2] == 0x08 && p[curr->len + 3] == 0x00) {
		break;
		}
		}

tests/component/imgdiff_test.cpp

+80 −0

Original line number	Diff line number	Diff line
		@@ -404,6 +404,86 @@ TEST(ImgdiffTest, image_mode_spurious_magic) {
		ASSERT_EQ(tgt, patched);
		}

		TEST(ImgdiffTest, image_mode_short_input1) {
		// src: "abcdefgh" + '0x1f8b0b'.
		const std::vector<char> src_data = { 'a', 'b', 'c', 'd', 'e', 'f',
		'g', 'h', '\x1f', '\x8b', '\x08' };
		const std::string src(src_data.cbegin(), src_data.cend());
		TemporaryFile src_file;
		ASSERT_TRUE(android::base::WriteStringToFile(src, src_file.path));

		// tgt: "abcdefgxyz".
		const std::vector<char> tgt_data = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'x', 'y', 'z' };
		const std::string tgt(tgt_data.cbegin(), tgt_data.cend());
		TemporaryFile tgt_file;
		ASSERT_TRUE(android::base::WriteStringToFile(tgt, tgt_file.path));

		TemporaryFile patch_file;
		std::vector<const char*> args = {
		"imgdiff", src_file.path, tgt_file.path, patch_file.path,
		};
		ASSERT_EQ(0, imgdiff(args.size(), args.data()));

		// Verify.
		std::string patch;
		ASSERT_TRUE(android::base::ReadFileToString(patch_file.path, &patch));

		// Expect one CHUNK_RAW (header) entry.
		size_t num_normal;
		size_t num_raw;
		size_t num_deflate;
		verify_patch_header(patch, &num_normal, &num_raw, &num_deflate);
		ASSERT_EQ(0U, num_normal);
		ASSERT_EQ(0U, num_deflate);
		ASSERT_EQ(1U, num_raw);

		std::string patched;
		ASSERT_EQ(0, ApplyImagePatch(reinterpret_cast<const unsigned char*>(src.data()), src.size(),
		reinterpret_cast<const unsigned char*>(patch.data()), patch.size(),
		MemorySink, &patched));
		ASSERT_EQ(tgt, patched);
		}

		TEST(ImgdiffTest, image_mode_short_input2) {
		// src: "abcdefgh" + '0x1f8b0b00'.
		const std::vector<char> src_data = { 'a', 'b', 'c', 'd', 'e', 'f',
		'g', 'h', '\x1f', '\x8b', '\x08', '\x00' };
		const std::string src(src_data.cbegin(), src_data.cend());
		TemporaryFile src_file;
		ASSERT_TRUE(android::base::WriteStringToFile(src, src_file.path));

		// tgt: "abcdefgxyz".
		const std::vector<char> tgt_data = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'x', 'y', 'z' };
		const std::string tgt(tgt_data.cbegin(), tgt_data.cend());
		TemporaryFile tgt_file;
		ASSERT_TRUE(android::base::WriteStringToFile(tgt, tgt_file.path));

		TemporaryFile patch_file;
		std::vector<const char*> args = {
		"imgdiff", src_file.path, tgt_file.path, patch_file.path,
		};
		ASSERT_EQ(0, imgdiff(args.size(), args.data()));

		// Verify.
		std::string patch;
		ASSERT_TRUE(android::base::ReadFileToString(patch_file.path, &patch));

		// Expect one CHUNK_RAW (header) entry.
		size_t num_normal;
		size_t num_raw;
		size_t num_deflate;
		verify_patch_header(patch, &num_normal, &num_raw, &num_deflate);
		ASSERT_EQ(0U, num_normal);
		ASSERT_EQ(0U, num_deflate);
		ASSERT_EQ(1U, num_raw);

		std::string patched;
		ASSERT_EQ(0, ApplyImagePatch(reinterpret_cast<const unsigned char*>(src.data()), src.size(),
		reinterpret_cast<const unsigned char*>(patch.data()), patch.size(),
		MemorySink, &patched));
		ASSERT_EQ(tgt, patched);
		}

		TEST(ImgdiffTest, image_mode_single_entry_long) {
		// src: "abcdefgh" + '0x1f8b0b00' + some bytes.
		const std::vector<char> src_data = { 'a', 'b', 'c', 'd', 'e', 'f', 'g',