[FFmpeg-devel] [PATCH 5/5] avfilter/vf_blend: fix un-checked potential memory allocation failure

[Lynne]

2 Jan 2022, 15:51 by jianhua.wu-at-intel.com at ffmpeg.org:

> Signed-off-by: Wu Jianhua <jianhua.wu at intel.com>
> ---
>  libavfilter/vf_blend.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/libavfilter/vf_blend.c b/libavfilter/vf_blend.c
> index b6f3c4fed3..2d433e439f 100644
> --- a/libavfilter/vf_blend.c
> +++ b/libavfilter/vf_blend.c
> @@ -279,7 +279,11 @@ static AVFrame *blend_frame(AVFilterContext *ctx, AVFrame *top_buf,
>  dst_buf = ff_get_video_buffer(outlink, outlink->w, outlink->h);
>  if (!dst_buf)
>  return top_buf;
> -    av_frame_copy_props(dst_buf, top_buf);
> +
> +    if (av_frame_copy_props(dst_buf, top_buf) < 0) {
> +        av_frame_free(&dst_buf);
> +        return top_buf;
> +    }
>  
>  for (plane = 0; plane < s->nb_planes; plane++) {
>  int hsub = plane == 1 || plane == 2 ? s->hsub : 0;
>

Pushed patches 2 and 3. The blend filter doesn't work for me:
https://0x0.st/osRM.jpg
This is not what it's meant to look like at all, for blank, default options.

Patch 1 is a driver bug. The driver should not advertise the
HDR extension as supported if there's no swapchain. The HDR
extension explicitly requires a swapchain, and the Vulkan specs
say that devices are meant to only advertise supported extensions,
which the HDR extension wouldn't be if the swapchain extension
has not been loaded.
I pushed an alternative version that just removes the HDR extension,
but you need to notify your Windows driver developers that it's
not doing what it should.