[SCTP]: Fix IPv6 address flag setting when doing peel-off/accept.

During accept/peeloff we try to copy the list of bound addresses from
the original endpoint to the new one. However, we forgot to set the flag
to say that IPv6 is allowed on the new endpoint.
Signed-off-by: NVladislav Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: NSridhar Samudrala <sri@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/sctp/socket.c

@@ -5619,6 +5619,8 @@ static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
 	/* Copy the bind_addr list from the original endpoint to the new
 	 * endpoint so that we can handle restarts properly
 	 */
+	if (PF_INET6 == assoc->base.sk->sk_family)
+		flags = SCTP_ADDR6_ALLOWED;
 	if (assoc->peer.ipv4_address)
 		flags |= SCTP_ADDR4_PEERSUPP;
 	if (assoc->peer.ipv6_address)