soreuseport: fix merge conflict in tcp bind

One of the validation checks for the new array-based TCP SO_REUSEPORT
validation was unintentionally dropped in ea8add2b.  This adds it back.

Lack of this check allows the user to allocate multiple sock_reuseport
structures (leaking all but the first).

Fixes: ea8add2b ("tcp/dccp: better use of ephemeral ports in bind()")
Signed-off-by: NCraig Gallek <kraig@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/inet_connection_sock.c

@@ -202,6 +202,7 @@ int inet_csk_get_port(struct sock *sk, unsigned short snum)
 
 		if (((tb->fastreuse > 0 && reuse) ||
 		     (tb->fastreuseport > 0 &&
+		      !rcu_access_pointer(sk->sk_reuseport_cb) &&
 		      sk->sk_reuseport && uid_eq(tb->fastuid, uid))) &&
 		    smallest_size == -1)
 			goto success;