From aff6ff7ee5c0c353df6a3aa5c09fc66810c59b6e Mon Sep 17 00:00:00 2001
From: Guus Sliepen <guus@meshlink.io>
Date: Fri, 19 Jul 2019 14:40:36 +0200
Subject: [PATCH] Fix potential segmentation fault on node reachability change.

---
 src/graph.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/graph.c b/src/graph.c
index 8e39b98d..d779ecd5 100644
--- a/src/graph.c
+++ b/src/graph.c
@@ -237,13 +237,14 @@ static void check_reachability(meshlink_handle_t *mesh) {
 				update_node_udp(mesh, n, NULL);
 				n->status.broadcast = false;
 				n->options = 0;
-				utcp_offline(n->utcp, true);
 			} else if(n->connection) {
 				if(n->connection->outgoing) {
 					send_req_key(mesh, n);
 				}
+			}
 
-				utcp_offline(n->utcp, false);
+			if(n->utcp) {
+				utcp_offline(n->utcp, !n->status.reachable);
 			}
 		}
 	}
-- 
2.39.5