From ebb501ec73cecc546c67117dd01b5e33c90bfb4a Mon Sep 17 00:00:00 2001 From: Lasse Collin Date: Sun, 23 Jun 2013 17:36:47 +0300 Subject: [PATCH] xz: Validate Uncompressed Size from Block Header in list.c. This affects only "xz -lvv". Normal decompression with xz already detected if Block Header and Index had mismatched Uncompressed Size fields. So this just makes "xz -lvv" show such files as corrupt instead of showing the Uncompressed Size from Index. --- src/xz/list.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/src/xz/list.c b/src/xz/list.c index a9e0adb9..13abd8f7 100644 --- a/src/xz/list.c +++ b/src/xz/list.c @@ -456,7 +456,19 @@ parse_block_header(file_pair *pair, const lzma_index_iter *iter, switch (lzma_block_compressed_size(&block, iter->block.unpadded_size)) { case LZMA_OK: - break; + // Validate also block.uncompressed_size if it is present. + // If it isn't present, there's no need to set it since + // we aren't going to actually decompress the Block; if + // we were decompressing, then we should set it so that + // the Block decoder could validate the Uncompressed Size + // that was stored in the Index. + if (block.uncompressed_size == LZMA_VLI_UNKNOWN + || block.uncompressed_size + == iter->block.uncompressed_size) + break; + + // If the above fails, the file is corrupt so + // LZMA_DATA_ERROR is a good error code. case LZMA_DATA_ERROR: // Free the memory allocated by lzma_block_header_decode().