From 605f2b6b004eee4dc57832257169ff8eaa562fb7 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sun, 22 Apr 2012 12:16:29 +0200 Subject: [PATCH] asv1dec: check extradatasize before reading. Fixes null ptr dereference Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind Signed-off-by: Michael Niedermayer --- libavcodec/asv1.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/libavcodec/asv1.c b/libavcodec/asv1.c index c6e0c53000..702a59ee3f 100644 --- a/libavcodec/asv1.c +++ b/libavcodec/asv1.c @@ -553,8 +553,7 @@ static av_cold int decode_init(AVCodecContext *avctx){ ff_init_scantable(a->dsp.idct_permutation, &a->scantable, scantab); avctx->pix_fmt= PIX_FMT_YUV420P; - a->inv_qscale= avctx->extradata[0]; - if(a->inv_qscale == 0){ + if(avctx->extradata_size < 1 || (a->inv_qscale= avctx->extradata[0]) == 0){ av_log(avctx, AV_LOG_ERROR, "illegal qscale 0\n"); if(avctx->codec_id == CODEC_ID_ASV1) a->inv_qscale= 6;