[PATCH 3.2 058/152] decompress_bunzip2: off by one in get_next_block()
From: Ben Hutchings <hidden>
Date: 2015-02-17 02:14:57
Also in:
lkml
3.2.67-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Dan Carpenter <redacted>
commit b5c8afe5be51078a979d86ae5ae78c4ac948063d upstream.
"origPtr" is used as an offset into the bd->dbuf[] array. That array is
allocated in start_bunzip() and has "bd->dbufSize" number of elements so
the test here should be >= instead of >.
Later we check "origPtr" again before using it as an offset so I don't
know if this bug can be triggered in real life.
Fixes: bc22c17e12c1 ('bzip2/lzma: library support for gzip, bzip2 and lzma decompression')
Signed-off-by: Dan Carpenter <redacted>
Cc: Alain Knaff <redacted>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <redacted>
---
lib/decompress_bunzip2.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/lib/decompress_bunzip2.c
+++ b/lib/decompress_bunzip2.c@@ -185,7 +185,7 @@ static int INIT get_next_block(struct bu if (get_bits(bd, 1)) return RETVAL_OBSOLETE_INPUT; origPtr = get_bits(bd, 24); - if (origPtr > dbufSize) + if (origPtr >= dbufSize) return RETVAL_DATA_ERROR; /* mapping table: if some byte values are never used (encoding things like ascii text), the compression code removes the gaps to have fewer