diff --git a/libavformat/utils.c b/libavformat/utils.c
index 57fc836c64..5f3da495fd 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -622,7 +622,7 @@ int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputForma
     }
 
     s->duration = s->start_time = AV_NOPTS_VALUE;
-    av_strlcpy(s->filename, filename, sizeof(s->filename));
+    av_strlcpy(s->filename, filename ? filename : "", sizeof(s->filename));
 
     /* allocate private data */
     if (s->iformat->priv_data_size > 0) {