1 files changed, 6 insertions, 0 deletions

diff --git a/include/linux/if_arp.h b/include/linux/if_arp.h
index 296e8e86e91d..4d3401812e6c 100644
--- a/include/linux/if_arp.h
+++ b/include/linux/if_arp.h
@@ -156,6 +156,12 @@ static inline struct arphdr *arp_hdr(const struct sk_buff *skb)
 {
         return (struct arphdr *)skb_network_header(skb);
 }
+
+static inline int arp_hdr_len(struct net_device *dev)
+{
+        /* ARP header, plus 2 device addresses, plus 2 IP addresses. */
+        return sizeof(struct arphdr) + (dev->addr_len + sizeof(u32)) * 2;
+}
 #endif
 
 #endif  /* _LINUX_IF_ARP_H */