From 9dd5af78c845b1081634d010df6e7261e317f0dd Mon Sep 17 00:00:00 2001
From: Jens Dede <jd@comnets.uni-bremen.de>
Date: Tue, 23 Jul 2013 15:35:47 +0200
Subject: [PATCH] fix: default routes are removed correctly if no DAG with
 preferred parent is available

---
 core/net/rpl/rpl-dag.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/core/net/rpl/rpl-dag.c b/core/net/rpl/rpl-dag.c
index baad9946b..c404f6f4f 100644
--- a/core/net/rpl/rpl-dag.c
+++ b/core/net/rpl/rpl-dag.c
@@ -703,7 +703,9 @@ rpl_remove_parent(rpl_dag_t *dag, rpl_parent_t *parent)
 void
 rpl_nullify_parent(rpl_dag_t *dag, rpl_parent_t *parent)
 {
-  if(parent == dag->preferred_parent) {
+  // local repair calls nullification because the preferred parent is NULL!
+  // So check if parent is NULL to trigger uip_ds6_defrt_rm.
+  if(parent == dag->preferred_parent || dag->preferred_parent == NULL) {
     dag->preferred_parent = NULL;
     dag->rank = INFINITE_RANK;
     if(dag->joined) {