[IPSEC]: Fix panic when using inter address familiy IPsec on loopback.

Signed-off-by: Kazunori MIYAZAWA <kazunori@miyazawa.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/xfrm4_input.c

@@ -139,10 +139,8 @@ int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
 	nf_reset(skb);
 
 	if (decaps) {
-		if (!(skb->dev->flags&IFF_LOOPBACK)) {
 		dst_release(skb->dst);
 		skb->dst = NULL;
-		}
 		netif_rx(skb);
 		return 0;
 	} else {

net/ipv4/xfrm4_mode_tunnel.c

@@ -85,6 +85,8 @@ static int xfrm4_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
 	top_iph->saddr = x->props.saddr.a4;
 	top_iph->daddr = x->id.daddr.a4;
 
+	skb->protocol = htons(ETH_P_IP);
+
 	memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
 	return 0;
 }

net/ipv6/xfrm6_input.c

@@ -104,10 +104,8 @@ int xfrm6_rcv_spi(struct sk_buff *skb, __be32 spi)
 	nf_reset(skb);
 
 	if (decaps) {
-		if (!(skb->dev->flags&IFF_LOOPBACK)) {
 		dst_release(skb->dst);
 		skb->dst = NULL;
-		}
 		netif_rx(skb);
 		return -1;
 	} else {

net/ipv6/xfrm6_mode_tunnel.c

@@ -80,6 +80,7 @@ static int xfrm6_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
 	top_iph->hop_limit = dst_metric(dst->child, RTAX_HOPLIMIT);
 	ipv6_addr_copy(&top_iph->saddr, (struct in6_addr *)&x->props.saddr);
 	ipv6_addr_copy(&top_iph->daddr, (struct in6_addr *)&x->id.daddr);
+	skb->protocol = htons(ETH_P_IPV6);
 	return 0;
 }