diff --git a/graph.c b/graph.c
index 65e6e89..897ee51 100644
--- a/graph.c
+++ b/graph.c
@@ -40,16 +40,25 @@ void Graph_free(Graph *graph)
 
 Node *Node_new()
 {
-	return climblib_malloc(sizeof(Node));
+	Node *node;
+
+	if ((node = climblib_malloc(sizeof(Node)))) {
+		node->next = NULL;
+		node->edges = NULL;
+		node->type = NodeType_UNDEFINED;
+	}
+
+	return node;
 }
 
 Node *Node_new_formation(Formation *formation)
 {
 	Node *node;
 
-	node = Node_new();
-	node->type = NodeType_FORMATION;
-	node->data.formation = formation;
+	if ((node = Node_new())) {
+		node->type = NodeType_FORMATION;
+		node->data.formation = formation;
+	}
 
 	return node;
 }
@@ -59,9 +68,10 @@ Node *Node_new_climb(Climb *climb)
 
 	Node *node;
 
-	node = Node_new();
-	node->type = NodeType_CLIMB;
-	node->data.climb = climb;
+	if ((node = Node_new())) {
+		node->type = NodeType_CLIMB;
+		node->data.climb = climb;
+	}
 
 	return node;
 }
diff --git a/tests/graph.c b/tests/graph.c
index 35ba9e6..43bebf2 100644
--- a/tests/graph.c
+++ b/tests/graph.c
@@ -33,6 +33,11 @@ START_TEST(test_nodes)
 	Graph *graph;
 	Node *a, *b, *c, *n;
 
+	climblib_set_alloc(bad_malloc, NULL, NULL);
+	a = Node_new();
+	ck_assert_ptr_null(a);
+	climblib_set_alloc(NULL, NULL, NULL);
+
 	graph = Graph_new();
 
 	a = Node_new();
@@ -70,6 +75,11 @@ START_TEST(test_formation_node)
 	Formation *formation;
 	Node *formation_node;
 
+	climblib_set_alloc(bad_malloc, NULL, NULL);
+	formation_node = Node_new_formation(NULL);
+	ck_assert_ptr_null(formation_node);
+	climblib_set_alloc(NULL, NULL, NULL);
+
 	formation = Formation_new();
 	ck_assert_ptr_nonnull(formation_node = Node_new_formation(formation));
 
@@ -86,6 +96,11 @@ START_TEST(test_climb_node)
 	Climb *climb;
 	Node *climb_node;
 
+	climblib_set_alloc(bad_malloc, NULL, NULL);
+	climb_node = Node_new_climb(NULL);
+	ck_assert_ptr_null(climb_node);
+	climblib_set_alloc(NULL, NULL, NULL);
+
 	climb = Climb_new();
 	ck_assert_ptr_nonnull(climb_node = Node_new_climb(climb));