ipv6: add a struct inet6_skb_parm param to ipv6_opt_accepted()

ipv6_opt_accepted() assumes IP6CB(skb) holds the struct inet6_skb_parm
that it needs. Lets not assume this, as TCP stack might use a different
place.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/ipv6.h

@@ -288,7 +288,8 @@ struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
 					  struct ipv6_txoptions *opt);
 
-bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb);
+bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
+		       const struct inet6_skb_parm *opt);
 
 static inline bool ipv6_accept_ra(struct inet6_dev *idev)
 {

net/dccp/ipv6.c

@@ -404,7 +404,7 @@ static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
 	ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
 	ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
 
-	if (ipv6_opt_accepted(sk, skb) ||
+	if (ipv6_opt_accepted(sk, skb, IP6CB(skb)) ||
 	    np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
 	    np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
 		atomic_inc(&skb->users);

net/ipv6/af_inet6.c

@@ -672,10 +672,10 @@ int inet6_sk_rebuild_header(struct sock *sk)
 }
 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
 
-bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb)
+bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
+		       const struct inet6_skb_parm *opt)
 {
 	const struct ipv6_pinfo *np = inet6_sk(sk);
-	const struct inet6_skb_parm *opt = IP6CB(skb);
 
 	if (np->rxopt.all) {
 		if ((opt->hop && (np->rxopt.bits.hopopts ||

net/ipv6/syncookies.c

@@ -203,7 +203,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 	ireq->ir_num = ntohs(th->dest);
 	ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
 	ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
-	if (ipv6_opt_accepted(sk, skb) ||
+	if (ipv6_opt_accepted(sk, skb, &TCP_SKB_CB(skb)->header.h6) ||
 	    np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
 	    np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
 		atomic_inc(&skb->users);

net/ipv6/tcp_ipv6.c

@@ -742,7 +742,8 @@ static void tcp_v6_init_req(struct request_sock *req, struct sock *sk,
 		ireq->ir_iif = inet6_iif(skb);
 
 	if (!TCP_SKB_CB(skb)->tcp_tw_isn &&
-	    (ipv6_opt_accepted(sk, skb) || np->rxopt.bits.rxinfo ||
+	    (ipv6_opt_accepted(sk, skb, &TCP_SKB_CB(skb)->header.h6) ||
+	     np->rxopt.bits.rxinfo ||
 	     np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim ||
 	     np->rxopt.bits.rxohlim || np->repflow)) {
 		atomic_inc(&skb->users);
@@ -1367,7 +1368,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
 			np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb));
 		if (np->repflow)
 			np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb));
-		if (ipv6_opt_accepted(sk, opt_skb)) {
+		if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) {
 			skb_set_owner_r(opt_skb, sk);
 			opt_skb = xchg(&np->pktoptions, opt_skb);
 		} else {