[FFmpeg-cvslog] Report an error if pitch_lag is zero in AMR-NB decoder.

[Oana Stratulat]

ffmpeg | branch: master | Oana Stratulat <oanaandreeastratulat at gmail.com> | Thu Jan  5 01:08:05 2012 +0200| [7f09791d28c82c9169d1612a6192851837341ca9] | committer: Ronald S. Bultje

Report an error if pitch_lag is zero in AMR-NB decoder.

This fixes an infinite loop in the decoder on specially
crafted files, and fixes bug 151.

Signed-off-by: Ronald S. Bultje <rsbultje at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7f09791d28c82c9169d1612a6192851837341ca9
---

 libavcodec/amrnbdec.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/libavcodec/amrnbdec.c b/libavcodec/amrnbdec.c
index 926014f..fff0e72 100644
--- a/libavcodec/amrnbdec.c
+++ b/libavcodec/amrnbdec.c
@@ -977,6 +977,10 @@ static int amrnb_decode_frame(AVCodecContext *avctx, void *data,
 
         pitch_sharpening(p, subframe, p->cur_frame_mode, &fixed_sparse);
 
+        if (fixed_sparse.pitch_lag == 0) {
+            av_log(avctx, AV_LOG_ERROR, "The file is corrupted, pitch_lag = 0 is not allowed\n");
+            return AVERROR_INVALIDDATA;
+        }
         ff_set_fixed_vector(p->fixed_vector, &fixed_sparse, 1.0,
                             AMR_SUBFRAME_SIZE);