diff --git a/libavfilter/avfilter.c b/libavfilter/avfilter.c
index f784cbff8c..7b4d853b69 100644
--- a/libavfilter/avfilter.c
+++ b/libavfilter/avfilter.c
@@ -75,8 +75,8 @@ void avfilter_unref_buffer(AVFilterBufferRef *ref)
         return;
     if (!(--ref->buf->refcount))
         ref->buf->free(ref->buf);
-    av_free(ref->video);
-    av_free(ref->audio);
+    av_freep(&ref->video);
+    av_freep(&ref->audio);
     av_free(ref);
 }