webrtcbin: Fix potential deadlock when closing before any data was sent

A blocking pad probe is added on new sink pads, it's usually removed after the
caps have been negotiated or the signaling state switched to stable, but if that
never happens and the pad is released we kept the pad probe active, leaving the
pad blocked, preventing clean disposal.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4533>

diff --git a/subprojects/gst-plugins-bad/ext/webrtc/gstwebrtcbin.c b/subprojects/gst-plugins-bad/ext/webrtc/gstwebrtcbin.c
index 6a8f722..8929fef 100644 (file)
--- a/subprojects/gst-plugins-bad/ext/webrtc/gstwebrtcbin.c
+++ b/subprojects/gst-plugins-bad/ext/webrtc/gstwebrtcbin.c
@@ -8184,6 +8184,11 @@ gst_webrtc_bin_release_pad (GstElement * element, GstPad * pad)
   gst_caps_replace (&webrtc_pad->received_caps, NULL);
   PC_UNLOCK (webrtc);
 
+  if (webrtc_pad->block_id) {
+    gst_pad_remove_probe (GST_PAD (pad), webrtc_pad->block_id);
+    webrtc_pad->block_id = 0;
+  }
+
   _remove_pad (webrtc, webrtc_pad);
 
   PC_LOCK (webrtc);