sctp: fix ignoring asoc_id for tcp-style sockets on SCTP_AUTH_KEY sockopt

A similar fix as Patch "sctp: fix ignoring asoc_id for tcp-style sockets on
SCTP_DEFAULT_SEND_PARAM sockopt" on SCTP_AUTH_KEY sockopt.

Fixes: 7fb3be13 ("sctp: use SCTP_FUTURE_ASSOC and add SCTP_CURRENT_ASSOC for SCTP_AUTH_KEY sockopt")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sctp/socket.c

@@ -3813,6 +3813,9 @@ static int sctp_setsockopt_auth_key(struct sock *sk,
 		goto out;
 	}
 
+	if (sctp_style(sk, TCP))
+		authkey->sca_assoc_id = SCTP_FUTURE_ASSOC;
+
 	if (authkey->sca_assoc_id == SCTP_FUTURE_ASSOC ||
 	    authkey->sca_assoc_id == SCTP_ALL_ASSOC) {
 		ret = sctp_auth_set_key(ep, asoc, authkey);