[SK_BUFF] xfrm: Use skb_set_mac_header in the memmove cases

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

1 files changed, 4 insertions, 2 deletions

diff --git a/net/ipv4/xfrm4_mode_tunnel.c b/net/ipv4/xfrm4_mode_tunnel.c
index 4872b30ba5d8..f09055d3a768 100644
--- a/net/ipv4/xfrm4_mode_tunnel.c
+++ b/net/ipv4/xfrm4_mode_tunnel.c
@@ -91,6 +91,7 @@ static int xfrm4_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
 static int xfrm4_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
 {
         struct iphdr *iph = skb->nh.iph;
+        const unsigned char *old_mac;
         int err = -EINVAL;
 
         switch (iph->protocol){
@@ -125,8 +126,9 @@ static int xfrm4_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
                 skb->protocol = htons(ETH_P_IPV6);
         }
 #endif
-        skb->mac.raw = memmove(skb->data - skb->mac_len,
-                               skb->mac.raw, skb->mac_len);
+        old_mac = skb->mac.raw;
+        skb_set_mac_header(skb, -skb->mac_len);
+        memmove(skb->mac.raw, old_mac, skb->mac_len);
         skb->nh.raw = skb->data;
         err = 0;