diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index e107754e29a7..1eb77161d5e6 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -3283,6 +3283,9 @@ static int nl80211_del_key(struct sk_buff *skb, struct genl_info *info)
 	if (err)
 		return err;
 
+	if (key.idx < 0)
+		return -EINVAL;
+
 	if (info->attrs[NL80211_ATTR_MAC])
 		mac_addr = nla_data(info->attrs[NL80211_ATTR_MAC]);