[GRE]: Fix hardware checksum modification
The skb_postpull_rcsum introduced a bug to the checksum modification.
Although the length pulled is offset bytes, the origin of the pulling
is the GRE header, not the IP header.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index a4c347c3..46f9d9c 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -618,7 +618,7 @@
skb->mac.raw = skb->nh.raw;
skb->nh.raw = __pskb_pull(skb, offset);
- skb_postpull_rcsum(skb, skb->mac.raw, offset);
+ skb_postpull_rcsum(skb, skb->h.raw, offset);
memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
skb->pkt_type = PACKET_HOST;
#ifdef CONFIG_NET_IPGRE_BROADCAST