[FFmpeg-devel] [PATCH] avcodec/dxva2: d3d11va: don't try to get surface description for nullptr

[Carl Eugen Hoyos]

2019-01-05 11:44 GMT+01:00, Anton Fedchin <afedchin at weezlabs.com>:
> From: Anton Fedchin <afedchin at ruswizards.com>
>
> after 153b36f there is a possibility to crash when trying to get index of
> a surface which points to nirvana. it may occurs when a stream starts with
> non i-frame.
> ---
>  libavcodec/dxva2.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/libavcodec/dxva2.c b/libavcodec/dxva2.c
> index 32416112bf..dfae500444 100644
> --- a/libavcodec/dxva2.c
> +++ b/libavcodec/dxva2.c
> @@ -771,16 +771,18 @@ unsigned ff_dxva2_get_surface_index(const
> AVCodecContext *avctx,
>  #if CONFIG_D3D11VA
>      if (avctx->pix_fmt == AV_PIX_FMT_D3D11)
>          return (intptr_t)frame->data[1];
> -    if (avctx->pix_fmt == AV_PIX_FMT_D3D11VA_VLD) {
> +    if (avctx->pix_fmt == AV_PIX_FMT_D3D11VA_VLD && surface) {
>          D3D11_VIDEO_DECODER_OUTPUT_VIEW_DESC viewDesc;
>
> ID3D11VideoDecoderOutputView_GetDesc((ID3D11VideoDecoderOutputView*)
> surface, &viewDesc);
>          return viewDesc.Texture2D.ArraySlice;
>      }
>  #endif

>  #if CONFIG_DXVA2
> -    for (i = 0; i < DXVA_CONTEXT_COUNT(avctx, ctx); i++) {
> -        if (avctx->pix_fmt == AV_PIX_FMT_DXVA2_VLD && ctx->dxva2.surface[i]
> == surface)
> -            return i;
> +    if (avctx->pix_fmt == AV_PIX_FMT_DXVA2_VLD) {
> +        for (i = 0; i < DXVA_CONTEXT_COUNT(avctx, ctx); i++) {
> +            if (ctx->dxva2.surface[i] == surface)
> +                return i;
> +        }

How is this change related?

Carl Eugen