ipv4: add support for IFA_FLAGS nl attribute

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 43065be..6f49efc9 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -99,6 +99,7 @@
 	[IFA_BROADCAST] 	= { .type = NLA_U32 },
 	[IFA_LABEL]     	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
+	[IFA_FLAGS]		= { .type = NLA_U32 },
 };
 
 #define IN4_ADDR_HSIZE_SHIFT	8
@@ -757,7 +758,8 @@
 	INIT_HLIST_NODE(&ifa->hash);
 	ifa->ifa_prefixlen = ifm->ifa_prefixlen;
 	ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
-	ifa->ifa_flags = ifm->ifa_flags;
+	ifa->ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) :
+					 ifm->ifa_flags;
 	ifa->ifa_scope = ifm->ifa_scope;
 	ifa->ifa_dev = in_dev;
 
@@ -1437,7 +1439,8 @@
 	       + nla_total_size(4) /* IFA_ADDRESS */
 	       + nla_total_size(4) /* IFA_LOCAL */
 	       + nla_total_size(4) /* IFA_BROADCAST */
-	       + nla_total_size(IFNAMSIZ); /* IFA_LABEL */
+	       + nla_total_size(IFNAMSIZ) /* IFA_LABEL */
+	       + nla_total_size(4);  /* IFA_FLAGS */
 }
 
 static inline u32 cstamp_delta(unsigned long cstamp)
@@ -1505,6 +1508,7 @@
 	     nla_put_be32(skb, IFA_BROADCAST, ifa->ifa_broadcast)) ||
 	    (ifa->ifa_label[0] &&
 	     nla_put_string(skb, IFA_LABEL, ifa->ifa_label)) ||
+	    nla_put_u32(skb, IFA_FLAGS, ifa->ifa_flags) ||
 	    put_cacheinfo(skb, ifa->ifa_cstamp, ifa->ifa_tstamp,
 			  preferred, valid))
 		goto nla_put_failure;