From 9593c80062e97b819a016dc36b6060d29667efaf Mon Sep 17 00:00:00 2001
From: Reinhard Tartler <siretart@tauware.de>
Date: Thu, 11 Feb 2010 21:03:30 +0000
Subject: [PATCH] Fix crash in MLP decoder due to integer overflow. Probably
 only DoS, init_get_bits sets buffer to NULL, thus causing a NULL-dereference
 directly after.

backport r21426 by reimar


Originally committed as revision 21759 to svn://svn.ffmpeg.org/ffmpeg/branches/0.5
---
 libavcodec/mlpdec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/mlpdec.c b/libavcodec/mlpdec.c
index 99754b329c..f1668afea0 100644
--- a/libavcodec/mlpdec.c
+++ b/libavcodec/mlpdec.c
@@ -878,7 +878,7 @@ static int read_access_unit(AVCodecContext *avctx, void* data, int *data_size,
 
     length = (AV_RB16(buf) & 0xfff) * 2;
 
-    if (length > buf_size)
+    if (length < 4 || length > buf_size)
         return -1;
 
     init_get_bits(&gb, (buf + 4), (length - 4) * 8);