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

[Wu, Jianhua]

 Lynne:
> Sent: Monday, January 3, 2022 10:23 AM
> To: FFmpeg development discussions and patches <ffmpeg-
> devel at ffmpeg.org>
> Subject: Re: [FFmpeg-devel] [PATCH 5/5] avfilter/vf_blend: fix un-checked
> potential memory allocation failure
> 
> 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.
> 

I'm afraid of it's not the problem of the blend_vulkan filter. Could you help try the other Vulkan filters and
see if they are still work?

> 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.
> 

Removing it is okay if it  is not used totally. And I' sorry we may have a mistake here.
Below is my development environment on this patch:
Operating System: Windows 10
Physical Device: Nvidia RTX3070
Driver version: GeForce Game Ready Driver 497.29
I'll add something like these to commit message if I fix similar problems.

And there is one more question, may I know why there is a suffix "@ffmpeg.org"
behind my commit Author email?

Thanks,
Jianhua