static void gs_usb_receive_bulk_callback(struct urb *urb)
{
	struct gs_usb *usbcan = urb->context;
	struct gs_can *dev;
	struct net_device *netdev;
	int rc;
	struct net_device_stats *stats;
	struct gs_host_frame *hf = urb->transfer_buffer;
	struct gs_tx_context *txc;
	struct can_frame *cf;
	struct sk_buff *skb;

	BUG_ON(!usbcan);

	switch (urb->status) {
	case 0: /* success */
		break;
	case -ENOENT:
	case -ESHUTDOWN:
		return;
	default:
		/* do not resubmit aborted urbs. eg: when device goes down */
		return;
	}

	/* device reports out of range channel id */
	if (hf->channel >= GS_MAX_INTF)
		goto resubmit_urb;

	dev = usbcan->canch[hf->channel];

	netdev = dev->netdev;
	stats = &netdev->stats;

	if (!netif_device_present(netdev))
		return;

	if (hf->echo_id == -1) { /* normal rx */
		skb = alloc_can_skb(dev->netdev, &cf);
		if (!skb)
			return;

		cf->can_id = hf->can_id;

		cf->can_dlc = get_can_dlc(hf->can_dlc);
		memcpy(cf->data, hf->data, 8);

		/* ERROR frames tell us information about the controller */
		if (hf->can_id & CAN_ERR_FLAG)
			gs_update_state(dev, cf);

		netdev->stats.rx_packets++;
		netdev->stats.rx_bytes += hf->can_dlc;

		netif_rx(skb);
	} else { /* echo_id == hf->echo_id */
		if (hf->echo_id >= GS_MAX_TX_URBS) {
			netdev_err(netdev,
				   "Unexpected out of range echo id %d\n",
				   hf->echo_id);
			goto resubmit_urb;
		}

		netdev->stats.tx_packets++;
		netdev->stats.tx_bytes += hf->can_dlc;

		txc = gs_get_tx_context(dev, hf->echo_id);

		/* bad devices send bad echo_ids. */
		if (!txc) {
			netdev_err(netdev,
				   "Unexpected unused echo id %d\n",
				   hf->echo_id);
			goto resubmit_urb;
		}

		can_get_echo_skb(netdev, hf->echo_id);

		gs_free_tx_context(txc);

		netif_wake_queue(netdev);
	}

	if (hf->flags & GS_CAN_FLAG_OVERFLOW) {
		skb = alloc_can_err_skb(netdev, &cf);
		if (!skb)
			goto resubmit_urb;

		cf->can_id |= CAN_ERR_CRTL;
		cf->can_dlc = CAN_ERR_DLC;
		cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
		stats->rx_over_errors++;
		stats->rx_errors++;
		netif_rx(skb);
	}

 resubmit_urb:
	usb_fill_bulk_urb(urb,
			  usbcan->udev,
			  usb_rcvbulkpipe(usbcan->udev, GSUSB_ENDPOINT_IN),
			  hf,
			  sizeof(struct gs_host_frame),
			  gs_usb_receive_bulk_callback,
			  usbcan
			  );

	rc = usb_submit_urb(urb, GFP_ATOMIC);

	/* USB failure take down all interfaces */
	if (rc == -ENODEV) {
		for (rc = 0; rc < GS_MAX_INTF; rc++) {
			if (usbcan->canch[rc])
				netif_device_detach(usbcan->canch[rc]->netdev);
		}
	}
}

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.