[FFmpeg-devel] [PATCH 1/5] avcodec/decode: Check for more invalid channel counts

[James Almer]

On 9/15/2022 10:10 PM, Andreas Rheinhardt wrote:
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
> Maybe use av_channel_layout_check?
> 
>   libavcodec/decode.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/libavcodec/decode.c b/libavcodec/decode.c
> index 2961705c9d..e24005cc44 100644
> --- a/libavcodec/decode.c
> +++ b/libavcodec/decode.c
> @@ -1595,7 +1595,7 @@ FF_DISABLE_DEPRECATION_WARNINGS
>   FF_ENABLE_DEPRECATION_WARNINGS
>   #endif
>   
> -    if (avctx->codec_type == AVMEDIA_TYPE_AUDIO && avctx->ch_layout.nb_channels == 0 &&
> +    if (avctx->codec_type == AVMEDIA_TYPE_AUDIO && avctx->ch_layout.nb_channels <= 0 &&
>           !(avctx->codec->capabilities & AV_CODEC_CAP_CHANNEL_CONF)) {
>           av_log(avctx, AV_LOG_ERROR, "Decoder requires channel count but channels not set\n");
>           return AVERROR(EINVAL);

This is a AV_CODEC_CAP_CHANNEL_CONF specific check to see if a channel 
count is set. A general sanity check like < 0 should be in 
avcodec_open2() before the ff_decode_preinit() call, next to (or as part 
of) the similar FF_SANE_NB_CHANNELS check, IMO.