[FFmpeg-devel] [PATCH] avcodec/cbs_h2645: Skip all 0 NAL units

[James Almer]

On 12/13/2019 7:17 PM, Michael Niedermayer wrote:
> Fixes: assertion failure
> Fixes: 19286/clusterfuzz-testcase-minimized-ffmpeg_BSF_H264_REDUNDANT_PPS_fuzzer-5707990724509696
> 
> 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/cbs_h2645.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/libavcodec/cbs_h2645.c b/libavcodec/cbs_h2645.c
> index 5f71d80584..90f77d0039 100644
> --- a/libavcodec/cbs_h2645.c
> +++ b/libavcodec/cbs_h2645.c
> @@ -568,7 +568,10 @@ static int cbs_h2645_fragment_add_nals(CodedBitstreamContext *ctx,
>          // Remove trailing zeroes.
>          while (size > 0 && nal->data[size - 1] == 0)
>              --size;
> -        av_assert0(size > 0);
> +        if (size == 0) {
> +            av_log(ctx->log_ctx, AV_LOG_WARNING, "Discarding empty 0 NAL unit\n");

IMO, no warning message, same as h2645_parse. Or if anything, make it
VERBOSE.

LGTM otherwise.

> +            continue;
> +        }
>  
>          ref = (nal->data == nal->raw_data) ? frag->data_ref
>                                             : packet->rbsp.rbsp_buffer_ref;
>