diff --git a/net/atm/clip.c b/net/atm/clip.c
index d5363ae5296a..8415ac280547 100644
--- a/net/atm/clip.c
+++ b/net/atm/clip.c
@@ -646,6 +646,9 @@ static struct atm_dev atmarpd_dev = {
 
 static int atm_init_atmarp(struct atm_vcc *vcc)
 {
+	if (vcc->push == clip_push)
+		return -EINVAL;
+
 	mutex_lock(&atmarpd_lock);
 	if (atmarpd) {
 		mutex_unlock(&atmarpd_lock);
@@ -670,6 +673,7 @@ static int atm_init_atmarp(struct atm_vcc *vcc)
 static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 {
 	struct atm_vcc *vcc = ATM_SD(sock);
+	struct sock *sk = sock->sk;
 	int err = 0;
 
 	switch (cmd) {
@@ -690,14 +694,18 @@ static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 		err = clip_create(arg);
 		break;
 	case ATMARPD_CTRL:
+		lock_sock(sk);
 		err = atm_init_atmarp(vcc);
 		if (!err) {
 			sock->state = SS_CONNECTED;
 			__module_get(THIS_MODULE);
 		}
+		release_sock(sk);
 		break;
 	case ATMARP_MKIP:
+		lock_sock(sk);
 		err = clip_mkip(vcc, arg);
+		release_sock(sk);
 		break;
 	case ATMARP_SETENTRY:
 		err = clip_setentry(vcc, (__force __be32)arg);