[FFmpeg-devel] [PATCH 1/5] avformat/electronicarts: If no packet has been read at the end do not treat it as if theres a packet

[Peter Ross]

On Tue, Oct 01, 2019 at 01:12:50AM +0200, Michael Niedermayer wrote:
> Fixes: Assertion failure
> Fixes: 17770/clusterfuzz-testcase-minimized-ffmpeg_DEMUXER_fuzzer-5700606668308480
> 
> Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> ---
>  libavformat/electronicarts.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/libavformat/electronicarts.c b/libavformat/electronicarts.c
> index 6dbc3e350a..c894663c29 100644
> --- a/libavformat/electronicarts.c
> +++ b/libavformat/electronicarts.c
> @@ -574,11 +574,12 @@ static int ea_read_packet(AVFormatContext *s, AVPacket *pkt)
>      EaDemuxContext *ea = s->priv_data;
>      AVIOContext *pb    = s->pb;
>      int partial_packet = 0;
> +    int hit_end = 0;
>      unsigned int chunk_type, chunk_size;
>      int ret = 0, packet_read = 0, key = 0;
>      int av_uninit(num_samples);
>  
> -    while (!packet_read || partial_packet) {
> +    while ((!packet_read && !hit_end) || partial_packet) {
>          chunk_type = avio_rl32(pb);
>          chunk_size = ea->big_endian ? avio_rb32(pb) : avio_rl32(pb);
>          if (chunk_size < 8)
> @@ -676,7 +677,7 @@ static int ea_read_packet(AVFormatContext *s, AVPacket *pkt)
>              }
>              if (avio_feof(pb))
>                  ret = AVERROR_EOF;
> -            packet_read = 1;
> +            hit_end = 1;
>              break;
>  
>          case MVIh_TAG:
> @@ -737,6 +738,9 @@ get_video_packet:
>  
>      if (ret < 0 && partial_packet)
>          av_packet_unref(pkt);
> +    if (ret >= 0 && hit_end && !packet_read)
> +        return AVERROR(EAGAIN);
> +
>      return ret;
>  }

looks good.

-- Peter
loo(A907 E02F A6E5 0CD2 34CD 20D2 6760 79C5 AC40 DD6B)
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