From 92b8c9d89e7ae86bffa05393bb230d5a165b0148 Mon Sep 17 00:00:00 2001
From: Nicolas George <nicolas.george@normalesup.org>
Date: Sat, 18 Aug 2012 14:12:41 +0200
Subject: [PATCH] lavf/au: check bits per coded sample.

Without that, it would repeatedly produce empty packets
if the codec if forced to something invalid.

Fix trac ticket #1652.
---
 libavformat/au.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/libavformat/au.c b/libavformat/au.c
index b7654a417a..788e261e70 100644
--- a/libavformat/au.c
+++ b/libavformat/au.c
@@ -181,10 +181,13 @@ static int au_read_packet(AVFormatContext *s,
                           AVPacket *pkt)
 {
     int ret;
+    int bpcs = av_get_bits_per_sample(s->streams[0]->codec->codec_id);
 
+    if (!bpcs)
+        return AVERROR(EINVAL);
     ret= av_get_packet(s->pb, pkt, BLOCK_SIZE *
                        s->streams[0]->codec->channels *
-                       av_get_bits_per_sample(s->streams[0]->codec->codec_id) >> 3);
+                       bpcs >> 3);
     if (ret < 0)
         return ret;
     pkt->flags &= ~AV_PKT_FLAG_CORRUPT;