static void tun_rx_batched(struct tun_struct *tun, struct tun_file *tfile,
			   struct sk_buff *skb, int more)
{
	struct sk_buff_head *queue = &tfile->sk.sk_write_queue;
	struct sk_buff_head process_queue;
	u32 rx_batched = tun->rx_batched;
	bool rcv = false;

	if (!rx_batched || (!more && skb_queue_empty(queue))) {
		local_bh_disable();
		netif_receive_skb(skb);
		local_bh_enable();
		return;
	}

	spin_lock(&queue->lock);
	if (!more || skb_queue_len(queue) == rx_batched) {
		__skb_queue_head_init(&process_queue);
		skb_queue_splice_tail_init(queue, &process_queue);
		rcv = true;
	} else {
		__skb_queue_tail(queue, skb);
	}
	spin_unlock(&queue->lock);

	if (rcv) {
		struct sk_buff *nskb;

		local_bh_disable();
		while ((nskb = __skb_dequeue(&process_queue)))
			netif_receive_skb(nskb);
		netif_receive_skb(skb);
		local_bh_enable();
	}
}

The product dereferences a pointer that it expects to be valid but is NULL.