[FFmpeg-devel] [PATCH] avcodec/snowdec: Check intra block dc differences.

[Ronald S. Bultje]

Hi,

On Mon, Sep 4, 2017 at 12:11 PM, Michael Niedermayer <michael at niedermayer.cc
> wrote:

>          if(type){
> +            int ld, cbd, crd;
>              pred_mv(s, &mx, &my, 0, left, top, tr);
> -            l += get_symbol(&s->c, &s->block_state[32], 1);
> +            ld = get_symbol(&s->c, &s->block_state[32], 1);
> +            if (ld < -255 || ld > 255) {
> +                av_log(s->avctx, AV_LOG_ERROR, "Invalid (Out of range)
> intra luma block DC difference %d\n", ld);
> +                return AVERROR_INVALIDDATA;
> +            }
> +            l += ld;
>              if (s->nb_planes > 2) {
> -                cb+= get_symbol(&s->c, &s->block_state[64], 1);
> -                cr+= get_symbol(&s->c, &s->block_state[96], 1);
> +                cbd = get_symbol(&s->c, &s->block_state[64], 1);
> +                crd = get_symbol(&s->c, &s->block_state[96], 1);
> +                if (cbd < -255 || cbd > 255 || crd < -255 || crd > 255) {
> +                    av_log(s->avctx, AV_LOG_ERROR, "Invalid (Out of
> range) intra chroma block DC difference %d, %d\n", cbd, crd);
> +                    return AVERROR_INVALIDDATA;
> +                }
> +                cb += cbd;
> +                cr += crd;
>              }


I recognize the great improvements in your messages. They are much better
than before. They are still not appropriate for display to end users.
Please use ff_tlog(), as was suggested in the original thread.

Ronald