[FFmpeg-devel] [PATCH 1/5] avformat/mxfdec: fix klv_decode_ber_length return value usage

[Tomas Härdin]

sön 2018-05-27 klockan 21:21 +0200 skrev Marton Balint:
> > Signed-off-by: Marton Balint <cus at passwd.hu>
> ---
>  libavformat/mxfdec.c | 15 ++++++++++++---
>  1 file changed, 12 insertions(+), 3 deletions(-)
> 
> diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
> index 7a42555562..40c9e0c3a9 100644
> --- a/libavformat/mxfdec.c
> +++ b/libavformat/mxfdec.c
> @@ -372,6 +372,8 @@ static int64_t klv_decode_ber_length(AVIOContext *pb)
>          while (bytes_num--)
>              size = size << 8 | avio_r8(pb);
>      }
> +    if (size > INT64_MAX)
> +        return AVERROR_INVALIDDATA;
>      return size;
>  }
>  
> @@ -390,13 +392,17 @@ static int mxf_read_sync(AVIOContext *pb, const uint8_t *key, unsigned size)
>  
>  static int klv_read_packet(KLVPacket *klv, AVIOContext *pb)
>  {
> +    int64_t length;
>      if (!mxf_read_sync(pb, mxf_klv_key, 4))
>          return AVERROR_INVALIDDATA;
>      klv->offset = avio_tell(pb) - 4;
>      memcpy(klv->key, mxf_klv_key, 4);
>      avio_read(pb, klv->key + 4, 12);
> -    klv->length = klv_decode_ber_length(pb);
> -    return klv->length == -1 ? -1 : 0;
> +    length = klv_decode_ber_length(pb);
> +    if (length < 0)
> +        return length;
> +    klv->length = length;
> +    return 0;
>  }

This feels like the kind of thing that should have been caught ages
ago. Are there any other -1's like this hiding in mxfdec? I took a
quick look but didn't find much

/Tomas