static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb,
				     struct net_device *netdev)
{
	struct gs_can *dev = netdev_priv(netdev);
	struct net_device_stats *stats = &dev->netdev->stats;
	struct urb *urb;
	struct gs_host_frame *hf;
	struct can_frame *cf;
	int rc;
	unsigned int idx;
	struct gs_tx_context *txc;

	if (can_dropped_invalid_skb(netdev, skb))
		return NETDEV_TX_OK;

	/* find an empty context to keep track of transmission */
	txc = gs_alloc_tx_context(dev);
	if (!txc)
		return NETDEV_TX_BUSY;

	/* create a URB, and a buffer for it */
	urb = usb_alloc_urb(0, GFP_ATOMIC);
	if (!urb)
		goto nomem_urb;

	hf = usb_alloc_coherent(dev->udev, sizeof(*hf), GFP_ATOMIC,
				&urb->transfer_dma);
	if (!hf) {
		netdev_err(netdev, "No memory left for USB buffer\n");
		goto nomem_hf;
	}

	idx = txc->echo_id;

	if (idx >= GS_MAX_TX_URBS) {
		netdev_err(netdev, "Invalid tx context %d\n", idx);
		goto badidx;
	}

	hf->echo_id = idx;
	hf->channel = dev->channel;

	cf = (struct can_frame *)skb->data;

	hf->can_id = cf->can_id;
	hf->can_dlc = cf->can_dlc;
	memcpy(hf->data, cf->data, cf->can_dlc);

	usb_fill_bulk_urb(urb, dev->udev,
			  usb_sndbulkpipe(dev->udev, GSUSB_ENDPOINT_OUT),
			  hf,
			  sizeof(*hf),
			  gs_usb_xmit_callback,
			  txc);

	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
	usb_anchor_urb(urb, &dev->tx_submitted);

	can_put_echo_skb(skb, netdev, idx);

	atomic_inc(&dev->active_tx_urbs);

	rc = usb_submit_urb(urb, GFP_ATOMIC);
	if (unlikely(rc)) {			/* usb send failed */
		atomic_dec(&dev->active_tx_urbs);

		can_free_echo_skb(netdev, idx);
		gs_free_tx_context(txc);

		usb_unanchor_urb(urb);
		usb_free_coherent(dev->udev,
				  sizeof(*hf),
				  hf,
				  urb->transfer_dma);


		if (rc == -ENODEV) {
			netif_device_detach(netdev);
		} else {
			netdev_err(netdev, "usb_submit failed (err=%d)\n", rc);
			stats->tx_dropped++;
		}
	} else {
		/* Slow down tx path */
		if (atomic_read(&dev->active_tx_urbs) >= GS_MAX_TX_URBS)
			netif_stop_queue(netdev);
	}

	/* let usb core take care of this urb */
	usb_free_urb(urb);

	return NETDEV_TX_OK;

 badidx:
	usb_free_coherent(dev->udev,
			  sizeof(*hf),
			  hf,
			  urb->transfer_dma);
 nomem_hf:
	usb_free_urb(urb);

 nomem_urb:
	gs_free_tx_context(txc);
	dev_kfree_skb(skb);
	stats->tx_dropped++;
	return NETDEV_TX_OK;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.