static int firm_send_command(struct usb_serial_port *port, __u8 command,
						__u8 *data, __u8 datasize)
{
	struct usb_serial_port *command_port;
	struct whiteheat_command_private *command_info;
	struct whiteheat_private *info;
	struct device *dev = &port->dev;
	__u8 *transfer_buffer;
	int retval = 0;
	int t;

	dev_dbg(dev, "%s - command %d\n", __func__, command);

	command_port = port->serial->port[COMMAND_PORT];
	command_info = usb_get_serial_port_data(command_port);
	mutex_lock(&command_info->mutex);
	command_info->command_finished = false;

	transfer_buffer = (__u8 *)command_port->write_urb->transfer_buffer;
	transfer_buffer[0] = command;
	memcpy(&transfer_buffer[1], data, datasize);
	command_port->write_urb->transfer_buffer_length = datasize + 1;
	retval = usb_submit_urb(command_port->write_urb, GFP_NOIO);
	if (retval) {
		dev_dbg(dev, "%s - submit urb failed\n", __func__);
		goto exit;
	}

	/* wait for the command to complete */
	t = wait_event_timeout(command_info->wait_command,
		(bool)command_info->command_finished, COMMAND_TIMEOUT);
	if (!t)
		usb_kill_urb(command_port->write_urb);

	if (command_info->command_finished == false) {
		dev_dbg(dev, "%s - command timed out.\n", __func__);
		retval = -ETIMEDOUT;
		goto exit;
	}

	if (command_info->command_finished == WHITEHEAT_CMD_FAILURE) {
		dev_dbg(dev, "%s - command failed.\n", __func__);
		retval = -EIO;
		goto exit;
	}

	if (command_info->command_finished == WHITEHEAT_CMD_COMPLETE) {
		dev_dbg(dev, "%s - command completed.\n", __func__);
		switch (command) {
		case WHITEHEAT_GET_DTR_RTS:
			info = usb_get_serial_port_data(port);
			memcpy(&info->mcr, command_info->result_buffer,
					sizeof(struct whiteheat_dr_info));
				break;
		}
	}
exit:
	mutex_unlock(&command_info->mutex);
	return retval;
}

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.