[NETLINK]: Introduce nlmsg_hdr() helper

For the common "(struct nlmsghdr *)skb->data" sequence, so that we reduce the
number of direct accesses to skb->data and for consistency with all the other
cast skb member helpers.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 3 insertions, 3 deletions

diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index cac06c43f004..3ff753c6f197 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -807,7 +807,7 @@ static void nl_fib_input(struct sock *sk, int len)
         if (skb == NULL)
                 return;
 
-        nlh = (struct nlmsghdr *)skb->data;
+        nlh = nlmsg_hdr(skb);
         if (skb->len < NLMSG_SPACE(0) || skb->len < nlh->nlmsg_len ||
             nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*frn))) {
                 kfree_skb(skb);
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index 37362cd1d07f..238999e6e871 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -847,7 +847,7 @@ static inline void inet_diag_rcv_skb(struct sk_buff *skb)
 {
         if (skb->len >= NLMSG_SPACE(0)) {
                 int err;
-                struct nlmsghdr *nlh = (struct nlmsghdr *)skb->data;
+                struct nlmsghdr *nlh = nlmsg_hdr(skb);
 
                 if (nlh->nlmsg_len < sizeof(*nlh) ||
                     skb->len < nlh->nlmsg_len)
diff --git a/net/ipv4/netfilter/ip_queue.c b/net/ipv4/netfilter/ip_queue.c
index 15e0d2002235..17f7c988460c 100644
--- a/net/ipv4/netfilter/ip_queue.c
+++ b/net/ipv4/netfilter/ip_queue.c
@@ -497,7 +497,7 @@ ipq_rcv_skb(struct sk_buff *skb)
         if (skblen < sizeof(*nlh))
                 return;
 
-        nlh = (struct nlmsghdr *)skb->data;
+        nlh = nlmsg_hdr(skb);
         nlmsglen = nlh->nlmsg_len;
         if (nlmsglen < sizeof(*nlh) || skblen < nlmsglen)
                 return;