From f92e8cccf5813dd62b7c4a2bea072badc7a250cb Mon Sep 17 00:00:00 2001
From: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Date: Wed, 25 Feb 2015 22:55:44 +0100
Subject: [PATCH] avformat/adxdec: check avctx->channels for invalid values

This avoids a null pointer dereference of pkt->data.

Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 7faa40af982960608b117e20fec999b48011e5e0)

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
---
 libavformat/adxdec.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libavformat/adxdec.c b/libavformat/adxdec.c
index ab11d832d8..021042c608 100644
--- a/libavformat/adxdec.c
+++ b/libavformat/adxdec.c
@@ -41,6 +41,11 @@ static int adx_read_packet(AVFormatContext *s, AVPacket *pkt)
     AVCodecContext *avctx = s->streams[0]->codec;
     int ret, size;
 
+    if (avctx->channels <= 0) {
+        av_log(s, AV_LOG_ERROR, "invalid number of channels %d\n", avctx->channels);
+        return AVERROR_INVALIDDATA;
+    }
+
     size = BLOCK_SIZE * avctx->channels;
 
     pkt->pos = avio_tell(s->pb);