[FFmpeg-cvslog] twinvq: check bitrate for validity avoid division by 0

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Fri Nov  9 18:45:41 2012 +0100| [b8dc5f8bb3b14bfd2289a0444c7b706299555d97] | committer: Michael Niedermayer

twinvq: check bitrate for validity avoid division by 0

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b8dc5f8bb3b14bfd2289a0444c7b706299555d97
---

 libavcodec/twinvq.c |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libavcodec/twinvq.c b/libavcodec/twinvq.c
index f4eba4d..7281d9c 100644
--- a/libavcodec/twinvq.c
+++ b/libavcodec/twinvq.c
@@ -1142,6 +1142,11 @@ static av_cold int twin_decode_init(AVCodecContext *avctx)
 
     ibps = avctx->bit_rate / (1000 * avctx->channels);
 
+    if (ibps > 255) {
+        av_log(avctx, AV_LOG_ERROR, "unsupported per channel bitrate %dkbps\n", ibps);
+        return AVERROR_INVALIDDATA;
+    }
+
     switch ((isampf << 8) +  ibps) {
     case (8 <<8) +  8: tctx->mtab = &mode_08_08; break;
     case (11<<8) +  8: tctx->mtab = &mode_11_08; break;