net: Pass ndm_state to route netlink FDB notifications.

Before this change applications monitoring FDB notifications
were not able to determine whether a new FDB entry is permament
or not:
bridge fdb add f1:f2:f3:f4:f5:f8 dev sw0p1 temp self
bridge fdb add f1:f2:f3:f4:f5:f9 dev sw0p1 self

bridge monitor fdb

f1:f2:f3:f4:f5:f8 dev sw0p1 self permanent
f1:f2:f3:f4:f5:f9 dev sw0p1 self permanent

With this change ndm_state from the original netlink message
is passed to the new netlink message sent as notification.

bridge fdb add f1:f2:f3:f4:f5:f6 dev sw0p1 self
bridge fdb add f1:f2:f3:f4:f5:f7 dev sw0p1 temp self

bridge monitor fdb
f1:f2:f3:f4:f5:f6 dev sw0p1 self permanent
f1:f2:f3:f4:f5:f7 dev sw0p1 self static
Signed-off-by: Hubert Sokolowski <hubert.sokolowski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/rtnetlink.c

@@ -2564,7 +2564,7 @@ static int nlmsg_populate_fdb_fill(struct sk_buff *skb,
 				   struct net_device *dev,
 				   u8 *addr, u16 vid, u32 pid, u32 seq,
 				   int type, unsigned int flags,
-				   int nlflags)
+				   int nlflags, u16 ndm_state)
 {
 	struct nlmsghdr *nlh;
 	struct ndmsg *ndm;
@@ -2580,7 +2580,7 @@ static int nlmsg_populate_fdb_fill(struct sk_buff *skb,
 	ndm->ndm_flags	 = flags;
 	ndm->ndm_type	 = 0;
 	ndm->ndm_ifindex = dev->ifindex;
-	ndm->ndm_state   = NUD_PERMANENT;
+	ndm->ndm_state   = ndm_state;
 
 	if (nla_put(skb, NDA_LLADDR, ETH_ALEN, addr))
 		goto nla_put_failure;
@@ -2601,7 +2601,8 @@ static inline size_t rtnl_fdb_nlmsg_size(void)
 	return NLMSG_ALIGN(sizeof(struct ndmsg)) + nla_total_size(ETH_ALEN);
 }
 
-static void rtnl_fdb_notify(struct net_device *dev, u8 *addr, u16 vid, int type)
+static void rtnl_fdb_notify(struct net_device *dev, u8 *addr, u16 vid, int type,
+			    u16 ndm_state)
 {
 	struct net *net = dev_net(dev);
 	struct sk_buff *skb;
@@ -2612,7 +2613,7 @@ static void rtnl_fdb_notify(struct net_device *dev, u8 *addr, u16 vid, int type)
 		goto errout;
 
 	err = nlmsg_populate_fdb_fill(skb, dev, addr, vid,
-				      0, 0, type, NTF_SELF, 0);
+				      0, 0, type, NTF_SELF, 0, ndm_state);
 	if (err < 0) {
 		kfree_skb(skb);
 		goto errout;
@@ -2747,7 +2748,8 @@ static int rtnl_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh)
 					       nlh->nlmsg_flags);
 
 		if (!err) {
-			rtnl_fdb_notify(dev, addr, vid, RTM_NEWNEIGH);
+			rtnl_fdb_notify(dev, addr, vid, RTM_NEWNEIGH,
+					ndm->ndm_state);
 			ndm->ndm_flags &= ~NTF_SELF;
 		}
 	}
@@ -2848,7 +2850,8 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh)
 			err = ndo_dflt_fdb_del(ndm, tb, dev, addr, vid);
 
 		if (!err) {
-			rtnl_fdb_notify(dev, addr, vid, RTM_DELNEIGH);
+			rtnl_fdb_notify(dev, addr, vid, RTM_DELNEIGH,
+					ndm->ndm_state);
 			ndm->ndm_flags &= ~NTF_SELF;
 		}
 	}
@@ -2876,7 +2879,7 @@ static int nlmsg_populate_fdb(struct sk_buff *skb,
 		err = nlmsg_populate_fdb_fill(skb, dev, ha->addr, 0,
 					      portid, seq,
 					      RTM_NEWNEIGH, NTF_SELF,
-					      NLM_F_MULTI);
+					      NLM_F_MULTI, NUD_PERMANENT);
 		if (err < 0)
 			return err;
 skip: