--- x/net/smc/af_smc.c
+++ y/net/smc/af_smc.c
@@ -127,6 +127,8 @@ static struct sock *smc_tcp_syn_recv_soc
 	struct sock *child;
 
 	smc = smc_clcsock_user_data(sk);
+	if (!smc)
+		goto drop;
 
 	if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) >
 				sk->sk_max_ack_backlog)