avfilter/formats: allow unknown channel layouts by default

Since the default in the libav fork is to only allow known layouts, making
unknown layouts allowed by default here can be a security risk for filters
directly merged from libav. However, usually it is simple to detect such cases,
use of av_get_channel_layout_nb_channels is a good indicator, so I suggest we
change this regardless.

See http://ffmpeg.org/pipermail/ffmpeg-devel/2016-November/203204.html.

This patch indirectly adds unknown channel layout support for filters where
query_formats is not specified:

abench
afifo
ainterleave
anullsink
apad
aperms
arealtime
aselect
asendcmd
asetnsamples
asetpts
asettb
ashowinfo
azmq

It introduces a query_formats callback for the asyncts filter, which only
supports known channel layouts since it is using libavresample.

And it removes .query_formats callback from filters where it was only there to
support unknown layouts, as this is now the default:

aloop
ametadata
anull
asidedata
asplit
atrim

Acked-by: Nicolas George <george@nsup.org>
Signed-off-by: Marton Balint <cus@passwd.hu>

1 files changed, 0 insertions, 1 deletions

diff --git a/libavfilter/af_anull.c b/libavfilter/af_anull.c
index fff456e8ea..1d0af451dc 100644
--- a/libavfilter/af_anull.c
+++ b/libavfilter/af_anull.c
@@ -46,7 +46,6 @@ static const AVFilterPad avfilter_af_anull_outputs[] = {
 AVFilter ff_af_anull = {
     .name          = "anull",
     .description   = NULL_IF_CONFIG_SMALL("Pass the source unchanged to the output."),
-    .query_formats = ff_query_formats_all,
     .inputs        = avfilter_af_anull_inputs,
     .outputs       = avfilter_af_anull_outputs,
 };