The patch 
c5adde9468b0714a051eac7f9666f23eb10b61f7 ("netlink:
eliminate nl_sk_hash_lock") introduced a bug where the EADDRINUSE
error has been replaced by ENOMEM.  This patch rectifies that
problem.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
 static int netlink_insert(struct sock *sk, struct net *net, u32 portid)
 {
        struct netlink_table *table = &nl_table[sk->sk_protocol];
-       int err = -EADDRINUSE;
+       int err;
 
        lock_sock(sk);
 
 
        nlk_sk(sk)->portid = portid;
        sock_hold(sk);
-       if (__netlink_insert(table, sk, net))
-               err = 0;
-       else
+
+       err = 0;
+       if (!__netlink_insert(table, sk, net)) {
+               err = -EADDRINUSE;
                sock_put(sk);
+       }
+
 err:
        release_sock(sk);
        return err;