[NETFILTER]: Keep conntrack reference until IPsec policy checks are done

Keep the conntrack reference until policy checks have been performed for
IPsec NAT support. The reference needs to be dropped before a packet is
queued to avoid having the conntrack module unloadable.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/raw.c

@@ -255,6 +255,7 @@ int raw_rcv(struct sock *sk, struct sk_buff *skb)
 		kfree_skb(skb);
 		return NET_RX_DROP;
 	}
+	nf_reset(skb);
 
 	skb_push(skb, skb->data - skb->nh.raw);