From: Lasse Collin <lasse.collin@tukaani.org>
Date: Wed, 23 Jan 2008 21:43:00 +0000 (+0200)
Subject: Fix decoding of empty Metadata Blocks, that don't have
X-Git-Tag: upstream/5.1.3~797
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=db9df0a9609c01a00a227329fb96e983971040f5;p=platform%2Fupstream%2Fxz.git

Fix decoding of empty Metadata Blocks, that don't have
even the Metadata Flags field. Earlier the code allowed
such files; now they are prohibited as the file format
specification requires.
---

diff --git a/src/liblzma/common/metadata_decoder.c b/src/liblzma/common/metadata_decoder.c
index 8ff4e25..579b0a5 100644
--- a/src/liblzma/common/metadata_decoder.c
+++ b/src/liblzma/common/metadata_decoder.c
@@ -127,6 +127,8 @@ process(lzma_coder *coder, lzma_allocator *allocator)
 		if (coder->buffer[coder->buffer_pos] & 0x70)
 			return LZMA_HEADER_ERROR;
 
+		coder->todo_count = 0;
+
 		// If Size of Header Metadata is present, prepare the
 		// variable for variable-length integer decoding. Otherwise
 		// set it to LZMA_VLI_VALUE_UNKNOWN to indicate that the
@@ -535,7 +537,7 @@ metadata_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
 	metadata->extra = NULL;
 
 	next->coder->sequence = SEQ_FLAGS;
-	next->coder->todo_count = 0;
+	next->coder->todo_count = 1;
 	next->coder->pos = 0;
 	next->coder->tmp = 0;
 	next->coder->metadata = metadata;