[FFmpeg-cvslog] af_channelmap: properly set the supported output channel layouts

[Anton Khirnov]

ffmpeg | branch: master | Anton Khirnov <anton at khirnov.net> | Wed Jul 22 11:30:37 2015 +0200| [22ecfcd4c79cdf812fdf406525ddf0fd1f7114e4] | committer: Anton Khirnov

af_channelmap: properly set the supported output channel layouts

The current code expects query_formats() to be called exactly once, it
will leak if it's not called at all (filter initialized, but never
configured or used) or try to read freed memory if it's called more than
once.

Found-by: James Almer <jamrial at gmail.com>
CC: libav-stable at libav.org

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=22ecfcd4c79cdf812fdf406525ddf0fd1f7114e4
---

 libavfilter/af_channelmap.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/libavfilter/af_channelmap.c b/libavfilter/af_channelmap.c
index 3035405..5725498 100644
--- a/libavfilter/af_channelmap.c
+++ b/libavfilter/af_channelmap.c
@@ -57,7 +57,6 @@ enum MappingMode {
 #define MAX_CH 64
 typedef struct ChannelMapContext {
     const AVClass *class;
-    AVFilterChannelLayouts *channel_layouts;
     char *mapping_str;
     char *channel_layout_str;
     uint64_t output_layout;
@@ -276,8 +275,6 @@ static av_cold int channelmap_init(AVFilterContext *ctx)
         return AVERROR(EINVAL);
     }
 
-    ff_add_channel_layout(&s->channel_layouts, s->output_layout);
-
     if (mode == MAP_PAIR_INT_STR || mode == MAP_PAIR_STR_STR) {
         for (i = 0; i < s->nch; i++) {
             s->map[i].out_channel_idx = av_get_channel_layout_channel_index(
@@ -291,11 +288,14 @@ static av_cold int channelmap_init(AVFilterContext *ctx)
 static int channelmap_query_formats(AVFilterContext *ctx)
 {
     ChannelMapContext *s = ctx->priv;
+    AVFilterChannelLayouts *channel_layouts = NULL;
+
+    ff_add_channel_layout(&channel_layouts, s->output_layout);
 
     ff_set_common_formats(ctx, ff_planar_sample_fmts());
     ff_set_common_samplerates(ctx, ff_all_samplerates());
     ff_channel_layouts_ref(ff_all_channel_layouts(), &ctx->inputs[0]->out_channel_layouts);
-    ff_channel_layouts_ref(s->channel_layouts,       &ctx->outputs[0]->in_channel_layouts);
+    ff_channel_layouts_ref(channel_layouts,          &ctx->outputs[0]->in_channel_layouts);
 
     return 0;
 }