From 6e02ea92ec8af1da74f55e616b7cda82740dccc0 Mon Sep 17 00:00:00 2001 From: Tao Bao Date: Thu, 17 Nov 2016 11:24:07 -0800 Subject: applypatch: Use unique_fd to avoid leaking FDs. Add unique_fd that calls ota_close() instead of the default closer. Test: recovery_component_test passes. Test: Apply a package that calls apply_patch(). Change-Id: I0c19921731757934f76cf7d5215916673a8f2777 --- applypatch/applypatch.cpp | 552 +++++++++++++++++++++++----------------------- otafault/ota_io.h | 10 + 2 files changed, 280 insertions(+), 282 deletions(-) diff --git a/applypatch/applypatch.cpp b/applypatch/applypatch.cpp index 5483a68da..9b84fa104 100644 --- a/applypatch/applypatch.cpp +++ b/applypatch/applypatch.cpp @@ -194,62 +194,59 @@ static int LoadPartitionContents(const std::string& filename, FileContents* file // Save the contents of the given FileContents object under the given // filename. Return 0 on success. int SaveFileContents(const char* filename, const FileContents* file) { - int fd = ota_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_SYNC, S_IRUSR | S_IWUSR); - if (fd < 0) { - printf("failed to open \"%s\" for write: %s\n", filename, strerror(errno)); - return -1; - } + unique_fd fd(ota_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_SYNC, S_IRUSR | S_IWUSR)); + if (fd == -1) { + printf("failed to open \"%s\" for write: %s\n", filename, strerror(errno)); + return -1; + } - ssize_t bytes_written = FileSink(file->data.data(), file->data.size(), &fd); - if (bytes_written != static_cast(file->data.size())) { - printf("short write of \"%s\" (%zd bytes of %zu) (%s)\n", - filename, bytes_written, file->data.size(), strerror(errno)); - ota_close(fd); - return -1; - } - if (ota_fsync(fd) != 0) { - printf("fsync of \"%s\" failed: %s\n", filename, strerror(errno)); - return -1; - } - if (ota_close(fd) != 0) { - printf("close of \"%s\" failed: %s\n", filename, strerror(errno)); - return -1; - } + ssize_t bytes_written = FileSink(file->data.data(), file->data.size(), &fd); + if (bytes_written != static_cast(file->data.size())) { + printf("short write of \"%s\" (%zd bytes of %zu): %s\n", filename, bytes_written, + file->data.size(), strerror(errno)); + return -1; + } + if (ota_fsync(fd) != 0) { + printf("fsync of \"%s\" failed: %s\n", filename, strerror(errno)); + return -1; + } + if (ota_close(fd) != 0) { + printf("close of \"%s\" failed: %s\n", filename, strerror(errno)); + return -1; + } - if (chmod(filename, file->st.st_mode) != 0) { - printf("chmod of \"%s\" failed: %s\n", filename, strerror(errno)); - return -1; - } - if (chown(filename, file->st.st_uid, file->st.st_gid) != 0) { - printf("chown of \"%s\" failed: %s\n", filename, strerror(errno)); - return -1; - } + if (chmod(filename, file->st.st_mode) != 0) { + printf("chmod of \"%s\" failed: %s\n", filename, strerror(errno)); + return -1; + } + if (chown(filename, file->st.st_uid, file->st.st_gid) != 0) { + printf("chown of \"%s\" failed: %s\n", filename, strerror(errno)); + return -1; + } - return 0; + return 0; } // Write a memory buffer to 'target' partition, a string of the form // "EMMC:[:...]". The target name // might contain multiple colons, but WriteToPartition() only uses the first // two and ignores the rest. Return 0 on success. -int WriteToPartition(const unsigned char* data, size_t len, const char* target) { - std::vector pieces = android::base::Split(std::string(target), ":"); - +int WriteToPartition(const unsigned char* data, size_t len, const std::string& target) { + std::vector pieces = android::base::Split(target, ":"); if (pieces.size() < 2 || pieces[0] != "EMMC") { - printf("WriteToPartition called with bad target (%s)\n", target); + printf("WriteToPartition called with bad target (%s)\n", target.c_str()); return -1; } const char* partition = pieces[1].c_str(); - - size_t start = 0; - bool success = false; - int fd = ota_open(partition, O_RDWR | O_SYNC); - if (fd < 0) { + unique_fd fd(ota_open(partition, O_RDWR)); + if (fd == -1) { printf("failed to open %s: %s\n", partition, strerror(errno)); return -1; } + size_t start = 0; + bool success = false; for (size_t attempt = 0; attempt < 2; ++attempt) { if (TEMP_FAILURE_RETRY(lseek(fd, start, SEEK_SET)) == -1) { printf("failed seek on %s: %s\n", partition, strerror(errno)); @@ -268,23 +265,23 @@ int WriteToPartition(const unsigned char* data, size_t len, const char* target) } if (ota_fsync(fd) != 0) { - printf("failed to sync to %s (%s)\n", partition, strerror(errno)); + printf("failed to sync to %s: %s\n", partition, strerror(errno)); return -1; } if (ota_close(fd) != 0) { - printf("failed to close %s (%s)\n", partition, strerror(errno)); + printf("failed to close %s: %s\n", partition, strerror(errno)); return -1; } - fd = ota_open(partition, O_RDONLY); - if (fd < 0) { - printf("failed to reopen %s for verify (%s)\n", partition, strerror(errno)); + fd.reset(ota_open(partition, O_RDONLY)); + if (fd == -1) { + printf("failed to reopen %s for verify: %s\n", partition, strerror(errno)); return -1; } // Drop caches so our subsequent verification read won't just be reading the cache. sync(); - int dc = ota_open("/proc/sys/vm/drop_caches", O_WRONLY); + unique_fd dc(ota_open("/proc/sys/vm/drop_caches", O_WRONLY)); if (TEMP_FAILURE_RETRY(ota_write(dc, "3\n", 2)) == -1) { printf("write to /proc/sys/vm/drop_caches failed: %s\n", strerror(errno)); } else { @@ -293,7 +290,7 @@ int WriteToPartition(const unsigned char* data, size_t len, const char* target) ota_close(dc); sleep(1); - // verify + // Verify. if (TEMP_FAILURE_RETRY(lseek(fd, 0, SEEK_SET)) == -1) { printf("failed to seek back to beginning of %s: %s\n", partition, strerror(errno)); return -1; @@ -318,8 +315,7 @@ int WriteToPartition(const unsigned char* data, size_t len, const char* target) return -1; } if (static_cast(read_count) < to_read) { - printf("short verify read %s at %zu: %zd %zu %s\n", partition, p, read_count, to_read, - strerror(errno)); + printf("short verify read %s at %zu: %zd %zu\n", partition, p, read_count, to_read); } so_far += read_count; } @@ -343,8 +339,8 @@ int WriteToPartition(const unsigned char* data, size_t len, const char* target) return -1; } - if (ota_close(fd) != 0) { - printf("error closing %s (%s)\n", partition, strerror(errno)); + if (ota_close(fd) == -1) { + printf("error closing %s: %s\n", partition, strerror(errno)); return -1; } sync(); @@ -586,50 +582,49 @@ int applypatch(const char* source_filename, */ int applypatch_flash(const char* source_filename, const char* target_filename, const char* target_sha1_str, size_t target_size) { - printf("flash %s: ", target_filename); + printf("flash %s: ", target_filename); - uint8_t target_sha1[SHA_DIGEST_LENGTH]; - if (ParseSha1(target_sha1_str, target_sha1) != 0) { - printf("failed to parse tgt-sha1 \"%s\"\n", target_sha1_str); - return 1; - } + uint8_t target_sha1[SHA_DIGEST_LENGTH]; + if (ParseSha1(target_sha1_str, target_sha1) != 0) { + printf("failed to parse tgt-sha1 \"%s\"\n", target_sha1_str); + return 1; + } - std::string target_str(target_filename); + std::string target_str(target_filename); + std::vector pieces = android::base::Split(target_str, ":"); + if (pieces.size() != 2 || pieces[0] != "EMMC") { + printf("invalid target name \"%s\"", target_filename); + return 1; + } - std::vector pieces = android::base::Split(target_str, ":"); - if (pieces.size() != 2 || pieces[0] != "EMMC") { - printf("invalid target name \"%s\"", target_filename); - return 1; - } + // Load the target into the source_file object to see if already applied. + pieces.push_back(std::to_string(target_size)); + pieces.push_back(target_sha1_str); + std::string fullname = android::base::Join(pieces, ':'); + FileContents source_file; + if (LoadPartitionContents(fullname, &source_file) == 0 && + memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) == 0) { + // The early-exit case: the image was already applied, this partition + // has the desired hash, nothing for us to do. + printf("already %s\n", short_sha1(target_sha1).c_str()); + return 0; + } - // Load the target into the source_file object to see if already applied. - pieces.push_back(std::to_string(target_size)); - pieces.push_back(target_sha1_str); - std::string fullname = android::base::Join(pieces, ':'); - FileContents source_file; - if (LoadPartitionContents(fullname, &source_file) == 0 && - memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) == 0) { - // The early-exit case: the image was already applied, this partition - // has the desired hash, nothing for us to do. - printf("already %s\n", short_sha1(target_sha1).c_str()); - return 0; - } - - if (LoadFileContents(source_filename, &source_file) == 0) { - if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) != 0) { - // The source doesn't have desired checksum. - printf("source \"%s\" doesn't have expected sha1 sum\n", source_filename); - printf("expected: %s, found: %s\n", short_sha1(target_sha1).c_str(), - short_sha1(source_file.sha1).c_str()); - return 1; - } + if (LoadFileContents(source_filename, &source_file) == 0) { + if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) != 0) { + // The source doesn't have desired checksum. + printf("source \"%s\" doesn't have expected sha1 sum\n", source_filename); + printf("expected: %s, found: %s\n", short_sha1(target_sha1).c_str(), + short_sha1(source_file.sha1).c_str()); + return 1; } + } - if (WriteToPartition(source_file.data.data(), target_size, target_filename) != 0) { - printf("write of copied data to %s failed\n", target_filename); - return 1; - } - return 0; + if (WriteToPartition(source_file.data.data(), target_size, target_filename) != 0) { + printf("write of copied data to %s failed\n", target_filename); + return 1; + } + return 0; } static int GenerateTarget(FileContents* source_file, @@ -641,221 +636,214 @@ static int GenerateTarget(FileContents* source_file, const uint8_t target_sha1[SHA_DIGEST_LENGTH], size_t target_size, const Value* bonus_data) { - int retry = 1; - SHA_CTX ctx; - std::string memory_sink_str; - FileContents* source_to_use; - int made_copy = 0; - - bool target_is_partition = (strncmp(target_filename, "EMMC:", 5) == 0); - const std::string tmp_target_filename = std::string(target_filename) + ".patch"; - - // assume that target_filename (eg "/system/app/Foo.apk") is located - // on the same filesystem as its top-level directory ("/system"). - // We need something that exists for calling statfs(). - std::string target_fs = target_filename; - auto slash_pos = target_fs.find('/', 1); - if (slash_pos != std::string::npos) { - target_fs.resize(slash_pos); - } - - const Value* patch; - if (source_patch_value != NULL) { - source_to_use = source_file; - patch = source_patch_value; - } else { - source_to_use = copy_file; - patch = copy_patch_value; - } - if (patch->type != VAL_BLOB) { - printf("patch is not a blob\n"); - return 1; - } - const char* header = &patch->data[0]; - size_t header_bytes_read = patch->data.size(); - bool use_bsdiff = false; - if (header_bytes_read >= 8 && memcmp(header, "BSDIFF40", 8) == 0) { - use_bsdiff = true; - } else if (header_bytes_read >= 8 && memcmp(header, "IMGDIFF2", 8) == 0) { - use_bsdiff = false; - } else { - printf("Unknown patch file format\n"); - return 1; - } + // assume that target_filename (eg "/system/app/Foo.apk") is located + // on the same filesystem as its top-level directory ("/system"). + // We need something that exists for calling statfs(). + std::string target_fs = target_filename; + auto slash_pos = target_fs.find('/', 1); + if (slash_pos != std::string::npos) { + target_fs.resize(slash_pos); + } - do { - // Is there enough room in the target filesystem to hold the patched - // file? - - if (target_is_partition) { - // If the target is a partition, we're actually going to - // write the output to /tmp and then copy it to the - // partition. statfs() always returns 0 blocks free for - // /tmp, so instead we'll just assume that /tmp has enough - // space to hold the file. - - // We still write the original source to cache, in case - // the partition write is interrupted. - if (MakeFreeSpaceOnCache(source_file->data.size()) < 0) { - printf("not enough free space on /cache\n"); - return 1; - } - if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) { - printf("failed to back up source file\n"); - return 1; - } - made_copy = 1; - retry = 0; - } else { - int enough_space = 0; - if (retry > 0) { - size_t free_space = FreeSpaceForFile(target_fs.c_str()); - enough_space = - (free_space > (256 << 10)) && // 256k (two-block) minimum - (free_space > (target_size * 3 / 2)); // 50% margin of error - if (!enough_space) { - printf("target %zu bytes; free space %zu bytes; retry %d; enough %d\n", - target_size, free_space, retry, enough_space); - } - } - - if (!enough_space) { - retry = 0; - } - - if (!enough_space && source_patch_value != NULL) { - // Using the original source, but not enough free space. First - // copy the source file to cache, then delete it from the original - // location. - - if (strncmp(source_filename, "EMMC:", 5) == 0) { - // It's impossible to free space on the target filesystem by - // deleting the source if the source is a partition. If - // we're ever in a state where we need to do this, fail. - printf("not enough free space for target but source is partition\n"); - return 1; - } - - if (MakeFreeSpaceOnCache(source_file->data.size()) < 0) { - printf("not enough free space on /cache\n"); - return 1; - } - - if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) { - printf("failed to back up source file\n"); - return 1; - } - made_copy = 1; - unlink(source_filename); - - size_t free_space = FreeSpaceForFile(target_fs.c_str()); - printf("(now %zu bytes free for target) ", free_space); - } - } + FileContents* source_to_use; + const Value* patch; + if (source_patch_value != nullptr) { + source_to_use = source_file; + patch = source_patch_value; + } else { + source_to_use = copy_file; + patch = copy_patch_value; + } + if (patch->type != VAL_BLOB) { + printf("patch is not a blob\n"); + return 1; + } - SinkFn sink = NULL; - void* token = NULL; - int output_fd = -1; - if (target_is_partition) { - // We store the decoded output in memory. - sink = MemorySink; - token = &memory_sink_str; - } else { - // We write the decoded output to ".patch". - output_fd = ota_open(tmp_target_filename.c_str(), O_WRONLY | O_CREAT | O_TRUNC | O_SYNC, - S_IRUSR | S_IWUSR); - if (output_fd < 0) { - printf("failed to open output file %s: %s\n", tmp_target_filename.c_str(), - strerror(errno)); - return 1; - } - sink = FileSink; - token = &output_fd; - } + const char* header = &patch->data[0]; + size_t header_bytes_read = patch->data.size(); + bool use_bsdiff = false; + if (header_bytes_read >= 8 && memcmp(header, "BSDIFF40", 8) == 0) { + use_bsdiff = true; + } else if (header_bytes_read >= 8 && memcmp(header, "IMGDIFF2", 8) == 0) { + use_bsdiff = false; + } else { + printf("Unknown patch file format\n"); + return 1; + } + bool target_is_partition = (strncmp(target_filename, "EMMC:", 5) == 0); + const std::string tmp_target_filename = std::string(target_filename) + ".patch"; - SHA1_Init(&ctx); + int retry = 1; + bool made_copy = false; + SHA_CTX ctx; + std::string memory_sink_str; // Don't need to reserve space. + do { + // Is there enough room in the target filesystem to hold the patched file? - int result; - if (use_bsdiff) { - result = ApplyBSDiffPatch(source_to_use->data.data(), source_to_use->data.size(), - patch, 0, sink, token, &ctx); - } else { - result = ApplyImagePatch(source_to_use->data.data(), source_to_use->data.size(), - patch, sink, token, &ctx, bonus_data); + if (target_is_partition) { + // If the target is a partition, we're actually going to + // write the output to /tmp and then copy it to the + // partition. statfs() always returns 0 blocks free for + // /tmp, so instead we'll just assume that /tmp has enough + // space to hold the file. + + // We still write the original source to cache, in case + // the partition write is interrupted. + if (MakeFreeSpaceOnCache(source_file->data.size()) < 0) { + printf("not enough free space on /cache\n"); + return 1; + } + if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) { + printf("failed to back up source file\n"); + return 1; + } + made_copy = true; + retry = 0; + } else { + bool enough_space = false; + if (retry > 0) { + size_t free_space = FreeSpaceForFile(target_fs.c_str()); + enough_space = (free_space > (256 << 10)) && // 256k (two-block) minimum + (free_space > (target_size * 3 / 2)); // 50% margin of error + if (!enough_space) { + printf("target %zu bytes; free space %zu bytes; retry %d; enough %d\n", target_size, + free_space, retry, enough_space); } + } + + if (!enough_space) { + retry = 0; + } - if (!target_is_partition) { - if (ota_fsync(output_fd) != 0) { - printf("failed to fsync file \"%s\" (%s)\n", tmp_target_filename.c_str(), - strerror(errno)); - result = 1; - } - if (ota_close(output_fd) != 0) { - printf("failed to close file \"%s\" (%s)\n", tmp_target_filename.c_str(), - strerror(errno)); - result = 1; - } + if (!enough_space && source_patch_value != nullptr) { + // Using the original source, but not enough free space. First + // copy the source file to cache, then delete it from the original + // location. + + if (strncmp(source_filename, "EMMC:", 5) == 0) { + // It's impossible to free space on the target filesystem by + // deleting the source if the source is a partition. If + // we're ever in a state where we need to do this, fail. + printf("not enough free space for target but source is partition\n"); + return 1; } - if (result != 0) { - if (retry == 0) { - printf("applying patch failed\n"); - return result != 0; - } else { - printf("applying patch failed; retrying\n"); - } - if (!target_is_partition) { - unlink(tmp_target_filename.c_str()); - } - } else { - // succeeded; no need to retry - break; + if (MakeFreeSpaceOnCache(source_file->data.size()) < 0) { + printf("not enough free space on /cache\n"); + return 1; } - } while (retry-- > 0); - uint8_t current_target_sha1[SHA_DIGEST_LENGTH]; - SHA1_Final(current_target_sha1, &ctx); - if (memcmp(current_target_sha1, target_sha1, SHA_DIGEST_LENGTH) != 0) { - printf("patch did not produce expected sha1\n"); + if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) { + printf("failed to back up source file\n"); + return 1; + } + made_copy = true; + unlink(source_filename); + + size_t free_space = FreeSpaceForFile(target_fs.c_str()); + printf("(now %zu bytes free for target) ", free_space); + } + } + + SinkFn sink = nullptr; + void* token = nullptr; + unique_fd output_fd; + if (target_is_partition) { + // We store the decoded output in memory. + sink = MemorySink; + token = &memory_sink_str; + } else { + // We write the decoded output to ".patch". + output_fd.reset(ota_open(tmp_target_filename.c_str(), O_WRONLY | O_CREAT | O_TRUNC | O_SYNC, + S_IRUSR | S_IWUSR)); + if (output_fd == -1) { + printf("failed to open output file %s: %s\n", tmp_target_filename.c_str(), strerror(errno)); return 1; + } + sink = FileSink; + token = &output_fd; + } + + SHA1_Init(&ctx); + + int result; + if (use_bsdiff) { + result = ApplyBSDiffPatch(source_to_use->data.data(), source_to_use->data.size(), patch, 0, + sink, token, &ctx); } else { - printf("now %s\n", short_sha1(target_sha1).c_str()); + result = ApplyImagePatch(source_to_use->data.data(), source_to_use->data.size(), patch, sink, + token, &ctx, bonus_data); } - if (target_is_partition) { - // Copy the temp file to the partition. - if (WriteToPartition(reinterpret_cast(memory_sink_str.c_str()), - memory_sink_str.size(), target_filename) != 0) { - printf("write of patched data to %s failed\n", target_filename); - return 1; - } + if (!target_is_partition) { + if (ota_fsync(output_fd) != 0) { + printf("failed to fsync file \"%s\": %s\n", tmp_target_filename.c_str(), strerror(errno)); + result = 1; + } + if (ota_close(output_fd) != 0) { + printf("failed to close file \"%s\": %s\n", tmp_target_filename.c_str(), strerror(errno)); + result = 1; + } + } + + if (result != 0) { + if (retry == 0) { + printf("applying patch failed\n"); + return 1; + } else { + printf("applying patch failed; retrying\n"); + } + if (!target_is_partition) { + unlink(tmp_target_filename.c_str()); + } } else { - // Give the .patch file the same owner, group, and mode of the - // original source file. - if (chmod(tmp_target_filename.c_str(), source_to_use->st.st_mode) != 0) { - printf("chmod of \"%s\" failed: %s\n", tmp_target_filename.c_str(), strerror(errno)); - return 1; - } - if (chown(tmp_target_filename.c_str(), source_to_use->st.st_uid, source_to_use->st.st_gid) != 0) { - printf("chown of \"%s\" failed: %s\n", tmp_target_filename.c_str(), strerror(errno)); - return 1; - } + // succeeded; no need to retry + break; + } + } while (retry-- > 0); - // Finally, rename the .patch file to replace the target file. - if (rename(tmp_target_filename.c_str(), target_filename) != 0) { - printf("rename of .patch to \"%s\" failed: %s\n", target_filename, strerror(errno)); - return 1; - } + uint8_t current_target_sha1[SHA_DIGEST_LENGTH]; + SHA1_Final(current_target_sha1, &ctx); + if (memcmp(current_target_sha1, target_sha1, SHA_DIGEST_LENGTH) != 0) { + printf("patch did not produce expected sha1\n"); + return 1; + } else { + printf("now %s\n", short_sha1(target_sha1).c_str()); + } + + if (target_is_partition) { + // Copy the temp file to the partition. + if (WriteToPartition(reinterpret_cast(memory_sink_str.c_str()), + memory_sink_str.size(), target_filename) != 0) { + printf("write of patched data to %s failed\n", target_filename); + return 1; + } + } else { + // Give the .patch file the same owner, group, and mode of the original source file. + if (chmod(tmp_target_filename.c_str(), source_to_use->st.st_mode) != 0) { + printf("chmod of \"%s\" failed: %s\n", tmp_target_filename.c_str(), strerror(errno)); + return 1; + } + if (chown(tmp_target_filename.c_str(), source_to_use->st.st_uid, + source_to_use->st.st_gid) != 0) { + printf("chown of \"%s\" failed: %s\n", tmp_target_filename.c_str(), strerror(errno)); + return 1; } - // If this run of applypatch created the copy, and we're here, we - // can delete it. - if (made_copy) { - unlink(CACHE_TEMP_SOURCE); + // Finally, rename the .patch file to replace the target file. + if (rename(tmp_target_filename.c_str(), target_filename) != 0) { + printf("rename of .patch to \"%s\" failed: %s\n", target_filename, strerror(errno)); + return 1; } + } - // Success! - return 0; + // If this run of applypatch created the copy, and we're here, we can delete it. + if (made_copy) { + unlink(CACHE_TEMP_SOURCE); + } + + // Success! + return 0; } diff --git a/otafault/ota_io.h b/otafault/ota_io.h index 84187a76e..e119eef08 100644 --- a/otafault/ota_io.h +++ b/otafault/ota_io.h @@ -26,6 +26,8 @@ #include #include +#include + #define OTAIO_CACHE_FNAME "/cache/saved.file" void ota_set_fault_files(); @@ -50,4 +52,12 @@ ssize_t ota_write(int fd, const void* buf, size_t nbyte); int ota_fsync(int fd); +struct OtaCloser { + static void Close(int fd) { + ota_close(fd); + } +}; + +using unique_fd = android::base::unique_fd_impl; + #endif -- cgit v1.2.3