qcacld-3.0: Validate NLA attr in hdd_extscan_epno_fill_network_list

NLA attribute
QCA_WLAN_VENDOR_ATTR_PNO_SET_LIST_PARAM_EPNO_NETWORKS_LIST
used without validation.

validate NLA attribute.

CRs-Fixed: 2025680
Change-Id: I4da7dbe44325b0ed6346b363b71b558250996f8c

core/hdd/src/wlan_hdd_ext_scan.c

@@ -3728,6 +3728,11 @@ static int hdd_extscan_epno_fill_network_list(
 
 	expected_networks = req_msg->num_networks;
 	index = 0;
+
+	if (!tb[QCA_WLAN_VENDOR_ATTR_PNO_SET_LIST_PARAM_EPNO_NETWORKS_LIST]) {
+		hdd_err("attr networks list failed");
+		return -EINVAL;
+	}
 	nla_for_each_nested(networks,
 			    tb[QCA_WLAN_VENDOR_ATTR_PNO_SET_LIST_PARAM_EPNO_NETWORKS_LIST],
 			    rem1) {