diff --git a/drivers/net/ethernet/toshiba/spider_net.c b/drivers/net/ethernet/toshiba/spider_net.c
index 50d7eacfec582..87e67121477cb 100644
--- a/drivers/net/ethernet/toshiba/spider_net.c
+++ b/drivers/net/ethernet/toshiba/spider_net.c
@@ -2332,7 +2332,7 @@ spider_net_alloc_card(void)
 	struct spider_net_card *card;
 
 	netdev = alloc_etherdev(struct_size(card, darray,
-					    tx_descriptors + rx_descriptors));
+					    size_add(tx_descriptors, rx_descriptors)));
 	if (!netdev)
 		return NULL;