[DCCP]: Dont use dccp_v4_checksum in dccp_make_response

dccp_make_response is shared by ipv4/6 and the ipv6 code was
recalculating the checksum, not good, so move the dccp_v4_checksum
call to dccp_v4_send_response.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/dccp/ipv4.c

@@ -264,7 +264,10 @@ static int dccp_v4_send_response(struct sock *sk, struct request_sock *req,
 	skb = dccp_make_response(sk, dst, req);
 	if (skb != NULL) {
 		const struct inet_request_sock *ireq = inet_rsk(req);
+		struct dccp_hdr *dh = dccp_hdr(skb);
 
+		dh->dccph_checksum = dccp_v4_checksum(skb, ireq->loc_addr,
+						      ireq->rmt_addr);
 		memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 		err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr,
 					    ireq->rmt_addr,

net/dccp/output.c

@@ -314,9 +314,6 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst,
 	dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dreq->dreq_isr);
 	dccp_hdr_response(skb)->dccph_resp_service = dreq->dreq_service;
 
-	dh->dccph_checksum = dccp_v4_checksum(skb, inet_rsk(req)->loc_addr,
-					      inet_rsk(req)->rmt_addr);
-
 	DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
 	return skb;
 }