From 46f72ea507afee6adb0d2324848159063d0e7afc Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Sat, 29 Mar 2014 04:25:50 +0100
Subject: [PATCH] avcodec/vp7: check buffer size

Fixes overread
Fixes Ticket 3501
Found-by: Piotr Bandurski <ami_stuff@o2.pl>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
---
 libavcodec/vp8.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libavcodec/vp8.c b/libavcodec/vp8.c
index 45a19a04e4..c15111e2dd 100644
--- a/libavcodec/vp8.c
+++ b/libavcodec/vp8.c
@@ -434,6 +434,11 @@ static int vp7_decode_frame_header(VP8Context *s, const uint8_t *buf, int buf_si
     s->invisible = 0;
     part1_size   = AV_RL24(buf) >> 4;
 
+    if (buf_size < 4 - s->profile + part1_size) {
+        av_log(s->avctx, AV_LOG_ERROR, "Buffer size %d is too small, needed : %d\n", buf_size, 4 - s->profile + part1_size);
+        return AVERROR_INVALIDDATA;
+    }
+
     buf      += 4 - s->profile;
     buf_size -= 4 - s->profile;