[FFmpeg-cvslog] avcodec/g729_parser: Check channels

[Michael Niedermayer]

ffmpeg | branch: release/4.3 | Michael Niedermayer <michael at niedermayer.cc> | Sun Feb 27 14:43:04 2022 +0100| [fa2e4afe8d0a23fac37392ef6506cfc9841f8d3d] | committer: Michael Niedermayer

avcodec/g729_parser: Check channels

Fixes: signed integer overflow: 10 * 808464428 cannot be represented in type 'int'
Fixes: assertion failure
Fixes: ticket9651

Reviewed-by: Paul B Mahol <onemda at gmail.com>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 757da974b21833529cc41bdcc9684c29660cdfa8)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=fa2e4afe8d0a23fac37392ef6506cfc9841f8d3d
---

 libavcodec/g729_parser.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavcodec/g729_parser.c b/libavcodec/g729_parser.c
index 010f688104..ef08b48bf3 100644
--- a/libavcodec/g729_parser.c
+++ b/libavcodec/g729_parser.c
@@ -49,6 +49,9 @@ static int g729_parse(AVCodecParserContext *s1, AVCodecContext *avctx,
         s->block_size = (avctx->bit_rate < 8000) ? G729D_6K4_BLOCK_SIZE : G729_8K_BLOCK_SIZE;
         if (avctx->codec_id == AV_CODEC_ID_ACELP_KELVIN)
             s->block_size++;
+        // channels > 2 is invalid, we pass the packet on unchanged
+        if (avctx->channels > 2)
+            s->block_size = 0;
         s->block_size *= avctx->channels;
         s->duration   = avctx->frame_size;
     }