[IPSEC] Use NLMSG_LENGTH in xfrm_exp_state_notify

Small fixup to use netlink macros instead of hardcoding.

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 9d30f732a273..ffe1b217347c 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1123,9 +1123,9 @@ nlmsg_failure:
 static int xfrm_exp_state_notify(struct xfrm_state *x, struct km_event *c)
 {
         struct sk_buff *skb;
+        int len = NLMSG_LENGTH(sizeof(struct xfrm_user_expire));
 
-        /* fix to do alloc using NLM macros */
-        skb = alloc_skb(sizeof(struct xfrm_user_expire) + 16, GFP_ATOMIC);
+        skb = alloc_skb(len, GFP_ATOMIC);
         if (skb == NULL)
                 return -ENOMEM;