From 70f9f075a0877074ac4e8492f7b78fd30d8b232f Mon Sep 17 00:00:00 2001
From: adamdunkels <adamdunkels>
Date: Mon, 10 Jan 2011 15:08:52 +0000
Subject: [PATCH] Safeguard against NULL arguments

---
 core/net/rime/collect-neighbor.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/core/net/rime/collect-neighbor.c b/core/net/rime/collect-neighbor.c
index 7e91ce855..b63d2106e 100644
--- a/core/net/rime/collect-neighbor.c
+++ b/core/net/rime/collect-neighbor.c
@@ -33,7 +33,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * $Id: collect-neighbor.c,v 1.9 2011/01/09 21:20:05 adamdunkels Exp $
+ * $Id: collect-neighbor.c,v 1.10 2011/01/10 15:08:52 adamdunkels Exp $
  */
 
 /**
@@ -144,6 +144,11 @@ collect_neighbor_list_add(struct collect_neighbor_list *neighbors_list,
 {
   struct collect_neighbor *n;
 
+  if(addr == NULL) {
+    PRINTF("collect_neighbor_list_add: attempt to add NULL addr\n");
+    return 0;
+  }
+
   PRINTF("collect_neighbor_add: adding %d.%d\n", addr->u8[0], addr->u8[1]);
 
   /* Check if the collect_neighbor is already on the list. */
@@ -195,8 +200,10 @@ collect_neighbor_list_add(struct collect_neighbor_list *neighbors_list,
     if(nrtmetric < worst_rtmetric) {
       n = worst_neighbor;
     }
-    PRINTF("collect_neighbor_add: not on list, not allocated, recycling %d.%d\n",
-           n->addr.u8[0], n->addr.u8[1]);
+    if(n != NULL) {
+      PRINTF("collect_neighbor_add: not on list, not allocated, recycling %d.%d\n",
+             n->addr.u8[0], n->addr.u8[1]);
+    }
   }
 
   if(n != NULL) {