static int hiddev_open(struct inode *inode, struct file *file)
{
	struct hiddev_list *list;
	struct usb_interface *intf;
	struct hid_device *hid;
	struct hiddev *hiddev;
	int res;

	intf = usbhid_find_interface(iminor(inode));
	if (!intf)
		return -ENODEV;
	hid = usb_get_intfdata(intf);
	hiddev = hid->hiddev;

	if (!(list = vzalloc(sizeof(struct hiddev_list))))
		return -ENOMEM;
	mutex_init(&list->thread_lock);
	list->hiddev = hiddev;
	file->private_data = list;

	/*
	 * no need for locking because the USB major number
	 * is shared which usbcore guards against disconnect
	 */
	if (list->hiddev->exist) {
		if (!list->hiddev->open++) {
			res = usbhid_open(hiddev->hid);
			if (res < 0) {
				res = -EIO;
				goto bail;
			}
		}
	} else {
		res = -ENODEV;
		goto bail;
	}

	spin_lock_irq(&list->hiddev->list_lock);
	list_add_tail(&list->node, &hiddev->list);
	spin_unlock_irq(&list->hiddev->list_lock);

	mutex_lock(&hiddev->existancelock);
	if (!list->hiddev->open++)
		if (list->hiddev->exist) {
			struct hid_device *hid = hiddev->hid;
			res = usbhid_get_power(hid);
			if (res < 0) {
				res = -EIO;
				goto bail_unlock;
			}
			usbhid_open(hid);
		}
	mutex_unlock(&hiddev->existancelock);
	return 0;
bail_unlock:
	mutex_unlock(&hiddev->existancelock);
bail:
	file->private_data = NULL;
	vfree(list);
	return res;
}

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.