[SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iph

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ah4.c b/net/ipv4/ah4.c
index 95ddbbd..00fd31d 100644
--- a/net/ipv4/ah4.c
+++ b/net/ipv4/ah4.c
@@ -65,7 +65,7 @@
 		char 		buf[60];
 	} tmp_iph;
 
-	top_iph = skb->nh.iph;
+	top_iph = ip_hdr(skb);
 	iph = &tmp_iph.iph;
 
 	iph->tos = top_iph->tos;
@@ -152,7 +152,7 @@
 	skb->ip_summed = CHECKSUM_NONE;
 
 	ah = (struct ip_auth_hdr*)skb->data;
-	iph = skb->nh.iph;
+	iph = ip_hdr(skb);
 
 	ihl = skb->data - skb_network_header(skb);
 	memcpy(work_buf, iph, ihl);