BACKPORT: ipv6/dccp: do not inherit ipv6_mc_list from parent

Like commit 657831ffc38e ("dccp/tcp: do not inherit mc_list from parent")
we should clear ipv6_mc_list etc. for IPv6 sockets too.

Cc: Eric Dumazet <[email protected]>
Bug: 62299478
Signed-off-by: Cong Wang <[email protected]>
Acked-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
(cherry picked from commit 83eaddab4378db256d00d295bda6ca997cd13a52)
Signed-off-by: Connor O'Brien <[email protected]>

Change-Id: I6bcb4627885b7444949852f580a901fdae409349
Signed-off-by: Francisco Franco <[email protected]>

net/dccp/ipv6.c

@@ -501,6 +501,9 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
 		newsk->sk_backlog_rcv = dccp_v4_do_rcv;
 		newnp->pktoptions  = NULL;
 		newnp->opt	   = NULL;
+		newnp->ipv6_mc_list = NULL;
+		newnp->ipv6_ac_list = NULL;
+		newnp->ipv6_fl_list = NULL;
 		newnp->mcast_oif   = inet6_iif(skb);
 		newnp->mcast_hops  = ipv6_hdr(skb)->hop_limit;
 
@@ -577,6 +580,10 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
 	/* Clone RX bits */
 	newnp->rxopt.all = np->rxopt.all;
 
+	newnp->ipv6_mc_list = NULL;
+	newnp->ipv6_ac_list = NULL;
+	newnp->ipv6_fl_list = NULL;
+
 	/* Clone pktoptions received with SYN */
 	newnp->pktoptions = NULL;
 	if (ireq6->pktopts != NULL) {

net/ipv6/tcp_ipv6.c

@@ -1285,6 +1285,7 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
 		newtp->af_specific = &tcp_sock_ipv6_mapped_specific;
 #endif
 
+		newnp->ipv6_mc_list = NULL;
 		newnp->ipv6_ac_list = NULL;
 		newnp->ipv6_fl_list = NULL;
 		newnp->pktoptions  = NULL;
@@ -1352,6 +1353,7 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
 	   First: no IPv4 options.
 	 */
 	newinet->inet_opt = NULL;
+	newnp->ipv6_mc_list = NULL;
 	newnp->ipv6_ac_list = NULL;
 	newnp->ipv6_fl_list = NULL;