netfilter: nfnetlink_queue: fix missing HW protocol

Locally generated IPv4 and IPv6 traffic gets skb->protocol unset,
thus passing zero.

ip6tables -I OUTPUT -j NFQUEUE
libmnl/examples/netfilter# ./nf-queue 0 &
ping6 ::1
packet received (id=1 hw=0x0000 hook=3)
                         ^^^^^^
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nfnetlink_queue_core.c

@@ -637,9 +637,6 @@ nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 	if (queue->copy_mode == NFQNL_COPY_NONE)
 		return -EINVAL;
 
-	if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(entry->skb))
-		return __nfqnl_enqueue_packet(net, queue, entry);
-
 	skb = entry->skb;
 
 	switch (entry->pf) {
@@ -651,6 +648,9 @@ nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 		break;
 	}
 
+	if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(skb))
+		return __nfqnl_enqueue_packet(net, queue, entry);
+
 	nf_bridge_adjust_skb_data(skb);
 	segs = skb_gso_segment(skb, 0);
 	/* Does not use PTR_ERR to limit the number of error codes that can be