diff --git a/ospfd/ospf_ase.c b/ospfd/ospf_ase.c
index 5d0cae4..3c19931 100644
--- a/ospfd/ospf_ase.c
+++ b/ospfd/ospf_ase.c
@@ -451,8 +451,8 @@
 
   /* if there is a Intra/Inter area route to the N
      do not install external route */
-  if (rn = route_node_lookup (ospf->new_table,
-			      (struct prefix *) &p))
+  if ((rn = route_node_lookup (ospf->new_table,
+			      (struct prefix *) &p)))
     {
       route_unlock_node(rn);
       if (rn->info == NULL)
@@ -463,8 +463,8 @@
     }
   /* Find a route to the same dest */
   /* If there is no route, create new one. */
-  if (rn = route_node_lookup (ospf->new_external_route,
-			       (struct prefix *) &p))
+  if ((rn = route_node_lookup (ospf->new_external_route,
+			       (struct prefix *) &p)))
       route_unlock_node(rn);
 
   if (!rn || (or = rn->info) == NULL)
@@ -718,7 +718,6 @@
 
   /* We assume that if LSA is deleted from DB
      is is also deleted from this RT */
-
   listnode_add (lst, ospf_lsa_lock (lsa)); /* external_lsas lst */
 }
 
@@ -799,7 +798,8 @@
     }
 
   rn = route_node_lookup (ospf->external_lsas, (struct prefix *) &p);
-  assert (rn && rn->info);
+  assert (rn); 
+  assert (rn->info);
   lsas = rn->info;
   route_unlock_node (rn);
 
diff --git a/ospfd/ospf_lsdb.c b/ospfd/ospf_lsdb.c
index c906f05..ea9a352 100644
--- a/ospfd/ospf_lsdb.c
+++ b/ospfd/ospf_lsdb.c
@@ -120,7 +120,10 @@
   
   /* nothing to do? */
   if (rn->info && rn->info == lsa)
-    return;
+    {
+      route_unlock_node (rn);
+      return;
+    }
   
   /* purge old entry? */
   if (rn->info)
@@ -162,12 +165,13 @@
       return;
     }
   
+  assert (lsa->data->type < OSPF_MAX_LSA);
   table = lsdb->type[lsa->data->type].db;
   lsdb_prefix_set (&lp, lsa);
-  rn = route_node_lookup (table, (struct prefix *) &lp);
-  if (rn && (rn->info == lsa))
+  if ((rn = route_node_lookup (table, (struct prefix *) &lp)))
     {
-      ospf_lsdb_delete_entry (lsdb, rn);
+      if (rn->info == lsa)
+        ospf_lsdb_delete_entry (lsdb, rn);
       route_unlock_node (rn); /* route_node_lookup */
     }
 }
@@ -274,7 +278,8 @@
       rn = route_top (table);
   else
     {
-      rn = route_node_get (table, (struct prefix *) &lp);
+      if ((rn = route_node_lookup (table, (struct prefix *) &lp)) == NULL)
+        return NULL;
       rn = route_next (rn);
     }