[FFmpeg-cvslog] ac3dec: Fix out-of-array read

[Tim Walker]

ffmpeg | branch: master | Tim Walker <tdskywalker at gmail.com> | Sat Nov 23 18:29:21 2013 +0100| [48b24bd2d208ce0f124029ac4c5ac5cb1fca4175] | committer: Diego Biurrun

ac3dec: Fix out-of-array read

Signed-off-by: Diego Biurrun <diego at biurrun.de>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=48b24bd2d208ce0f124029ac4c5ac5cb1fca4175
---

 libavcodec/ac3dec.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c
index e9ed040..7172e63 100644
--- a/libavcodec/ac3dec.c
+++ b/libavcodec/ac3dec.c
@@ -1367,8 +1367,6 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data,
             s->out_channels = 2;
             s->output_mode  = AC3_CHMODE_STEREO;
         }
-        avctx->channels       = s->out_channels;
-        avctx->channel_layout = avpriv_ac3_channel_layout_tab[s->output_mode];
 
         /* set downmixing coefficients if needed */
         if (s->channels != s->out_channels && !((s->output_mode & AC3_OUTPUT_LFEON) &&
@@ -1380,6 +1378,9 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data,
         return AVERROR_INVALIDDATA;
     }
     avctx->channels = s->out_channels;
+    avctx->channel_layout = avpriv_ac3_channel_layout_tab[s->output_mode & ~AC3_OUTPUT_LFEON];
+    if (s->output_mode & AC3_OUTPUT_LFEON)
+        avctx->channel_layout |= AV_CH_LOW_FREQUENCY;
 
     /* set audio service type based on bitstream mode for AC-3 */
     avctx->audio_service_type = s->bitstream_mode;