[FFmpeg-devel] [PATCH] avdevice/lavfi: fix crash on unconnected outpads

[Paul B Mahol]

On Thu, Jun 1, 2023 at 12:14 PM metamuffin <metamuffin at disroot.org> wrote:

> Nameless outpads would cause an invocation to sscanf with NULL.
> Example: ffmpeg -f lavfi -i 'nullsrc;nullsrc' -
> Changed to throwing an error instead.
>

See:

https://git.videolan.org/?p=ffmpeg.git;a=commit;h=5ce76506de1a7fbaf91af47a925d5ecfe13ae59c

Perhaps needs backporting to first introduction.


> ---
>  libavdevice/lavfi.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/libavdevice/lavfi.c b/libavdevice/lavfi.c
> index 9c1fcf334b..21f33ade0e 100644
> --- a/libavdevice/lavfi.c
> +++ b/libavdevice/lavfi.c
> @@ -174,6 +174,11 @@ av_cold static int lavfi_read_header(AVFormatContext
> *avctx)
>       * create a mapping between them and the streams */
>      for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
>          int stream_idx = 0, suffix = 0, use_subcc = 0;
> +        if (!inout->name) {
> +            av_log(avctx,  AV_LOG_ERROR,
> +                   "Filtergraph has nameless outpads\n");
> +            FAIL(AVERROR(EINVAL));
> +        }
>          sscanf(inout->name, "out%n%d%n", &suffix, &stream_idx, &suffix);
>          if (!suffix) {
>              av_log(avctx,  AV_LOG_ERROR,
> --
> 2.40.1
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".
>