Index: channels/chan_sip.c
===================================================================
--- channels/chan_sip.c	(revision 318547)
+++ channels/chan_sip.c	(working copy)
@@ -2754,7 +2754,7 @@
 	ast_debug(2, "Shutting down thread for %s server\n", tcptls_session->ssl ? "SSL" : "TCP");
 
 cleanup:
-	if (!tcptls_session->client && !authenticated) {
+	if (tcptls_session && !tcptls_session->client && !authenticated) {
 		ast_atomic_fetchadd_int(&unauth_sessions, -1);
 	}