[FFmpeg-devel] [PATCH v1 07/10] return value check for init_get_bits in vc1dec.c

[Hendrik Leppkes]

On Thu, Aug 12, 2021 at 6:53 AM maryam ebrahimzadeh <me22bee at outlook.com> wrote:
>
> ---
>  libavcodec/vc1dec.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/libavcodec/vc1dec.c b/libavcodec/vc1dec.c
> index 1fb1950ade..07d60294f2 100644
> --- a/libavcodec/vc1dec.c
> +++ b/libavcodec/vc1dec.c
> @@ -444,7 +444,9 @@ static av_cold int vc1_decode_init(AVCodecContext *avctx)
>          // the last byte of the extradata is a version number, 1 for the
>          // samples we can decode
>
> -        init_get_bits(&gb, avctx->extradata, avctx->extradata_size*8);
> +        ret = init_get_bits8(&gb, avctx->extradata, avctx->extradata_size);
> +        if (ret < 0)
> +            return ret;
>
>          if ((ret = ff_vc1_decode_sequence_header(avctx, v, &gb)) < 0)
>            return ret;
> @@ -771,7 +773,9 @@ static int vc1_decode_frame(AVCodecContext *avctx, void *data,
>          }
>          init_get_bits(&s->gb, buf2, buf_size2*8);
>      } else
> -        init_get_bits(&s->gb, buf, buf_size*8);
> +        ret = init_get_bits8(&s->gb, buf, buf_size);
> +        if (ret < 0)
> +            return ret;
>
>      if (v->res_sprite) {
>          v->new_sprite  = !get_bits1(&s->gb);

There is a whole bunch of other cases in vc1dec.c, I can even see one
in the patch context there. Any reason you picked only these two to
change?

- Hendrik