hns_nic_select_queue(struct net_device *ndev, struct sk_buff *skb,
		     void *accel_priv, select_queue_fallback_t fallback)
{
	struct ethhdr *eth_hdr = (struct ethhdr *)skb->data;
	struct hns_nic_priv *priv = netdev_priv(ndev);

	/* fix hardware broadcast/multicast packets queue loopback */
	if (!AE_IS_VER1(priv->enet_ver) &&
	    is_multicast_ether_addr(eth_hdr->h_dest))
		return 0;
	else
		return fallback(ndev, skb);
}

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.