[FFmpeg-devel] [PATCH 2/2] avcodec/cinepak: Check available input against encoded buffer size

[Tomas Härdin]

sön 2019-05-12 klockan 23:21 +0200 skrev Michael Niedermayer:
> Fixes: Timeout (12sec -> 2sec)
> Fixes: 14606/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_CINEPAK_fuzzer-5738687561728000
> 
> 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/cinepak.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/libavcodec/cinepak.c b/libavcodec/cinepak.c
> index a5132ddbc0..aeb15de0ed 100644
> --- a/libavcodec/cinepak.c
> +++ b/libavcodec/cinepak.c
> @@ -323,6 +323,9 @@ static int cinepak_predecode_check (CinepakContext *s)
>      num_strips  = AV_RB16 (&s->data[8]);
>      encoded_buf_size = AV_RB24(&s->data[1]);
>  
> +    if (s->size < encoded_buf_size * (int64_t)(100 - s->avctx->discard_damaged_percentage) / 100)
> +        return AVERROR_INVALIDDATA;

Looks OK

/Tomas