diff --git a/net/atm/lec.c b/net/atm/lec.c
index d7f5cf5b7594..ad4f829193f0 100644
--- a/net/atm/lec.c
+++ b/net/atm/lec.c
@@ -710,7 +710,10 @@ static int lec_vcc_attach(struct atm_vcc *vcc, void __user *arg)
 
 static int lec_mcast_attach(struct atm_vcc *vcc, int arg)
 {
-	if (arg < 0 || arg >= MAX_LEC_ITF || !dev_lec[arg])
+	if (arg < 0 || arg >= MAX_LEC_ITF)
+		return -EINVAL;
+	arg = array_index_nospec(arg, MAX_LEC_ITF);
+	if (!dev_lec[arg])
 		return -EINVAL;
 	vcc->proto_data = dev_lec[arg];
 	return lec_mcast_make(netdev_priv(dev_lec[arg]), vcc);
@@ -728,6 +731,7 @@ static int lecd_attach(struct atm_vcc *vcc, int arg)
 		i = arg;
 	if (arg >= MAX_LEC_ITF)
 		return -EINVAL;
+	i = array_index_nospec(arg, MAX_LEC_ITF);
 	if (!dev_lec[i]) {
 		int size;