From: Dan Carpenter Date: Sat, 13 Dec 2014 00:58:05 +0000 (-0800) Subject: decompress_bunzip2: off by one in get_next_block() X-Git-Tag: v3.2.67~95 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=c2895979352e50321dddd7156272890f9cd14de1 decompress_bunzip2: off by one in get_next_block() 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 Cc: Alain Knaff Cc: Yinghai Lu Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings --- diff --git a/lib/decompress_bunzip2.c b/lib/decompress_bunzip2.c index a7b80c1d6a0d..6a110e2759fa 100644 --- a/lib/decompress_bunzip2.c +++ b/lib/decompress_bunzip2.c @@ -185,7 +185,7 @@ static int INIT get_next_block(struct bunzip_data *bd) 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