neigh: use NEIGH_VAR_INIT in ndo_neigh_setup functions.

When ndo_neigh_setup is called, the bitfield used by NEIGH_VAR_SET is
not initialized yet. This might cause confusion for the people who use
NEIGH_VAR_SET in ndo_neigh_setup. So rather introduce NEIGH_VAR_INIT for
usage in ndo_neigh_setup.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/neighbour.h

@@ -92,6 +92,11 @@ static inline void neigh_var_set(struct neigh_parms *p, int index, int val)
 }
 
 #define NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])
+
+/* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
+ * In other cases, NEIGH_VAR_SET should be used.
+ */
+#define NEIGH_VAR_INIT(p, attr, val) (NEIGH_VAR(p, attr) = val)
 #define NEIGH_VAR_SET(p, attr, val) neigh_var_set(p, NEIGH_VAR_ ## attr, val)
 
 static inline void neigh_parms_data_state_setall(struct neigh_parms *p)

net/802/hippi.c

@@ -172,14 +172,14 @@ EXPORT_SYMBOL(hippi_mac_addr);
 int hippi_neigh_setup_dev(struct net_device *dev, struct neigh_parms *p)
 {
 	/* Never send broadcast/multicast ARP messages */
-	NEIGH_VAR_SET(p, MCAST_PROBES, 0);
+	NEIGH_VAR_INIT(p, MCAST_PROBES, 0);
 
 	/* In IPv6 unicast probes are valid even on NBMA,
 	* because they are encapsulated in normal IPv6 protocol.
 	* Should be a generic flag.
 	*/
 	if (p->tbl->family != AF_INET6)
-		NEIGH_VAR_SET(p, UCAST_PROBES, 0);
+		NEIGH_VAR_INIT(p, UCAST_PROBES, 0);
 	return 0;
 }
 EXPORT_SYMBOL(hippi_neigh_setup_dev);