[FFmpeg-devel] [PATCH 4/7] avcodec/rtv1: fix undefined FFALIGN

[James Almer]

On 3/25/2024 11:30 PM, Michael Niedermayer wrote:
> Fixes: signed integer overflow: 2147483647 + 4 cannot be represented in type 'int'
> Fixes: 62285/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_RTV1_fuzzer-6324303861514240
> 
> Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> ---
>   libavcodec/rtv1.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/libavcodec/rtv1.c b/libavcodec/rtv1.c
> index 06afe9e873c..807c8a34666 100644
> --- a/libavcodec/rtv1.c
> +++ b/libavcodec/rtv1.c
> @@ -113,6 +113,8 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *p,
>   
>       width = bytestream2_get_le32(&gb);
>       height = bytestream2_get_le32(&gb);
> +    if (width > INT_MAX-4U || height > INT_MAX-4U)

Does this promote width and height to unsigned? If not, you may want to 
cast them to unsigned (or check for < 0) and remove the then unnecessary 
U to the 4.

> +        return AVERROR_INVALIDDATA;
>       ret = ff_set_dimensions(avctx, FFALIGN(width, 4), FFALIGN(height, 4));
>       if (ret < 0)
>           return ret;