static int whiteheat_ioctl(struct tty_struct *tty,
					unsigned int cmd, unsigned long arg)
{
	struct usb_serial_port *port = tty->driver_data;
	struct serial_struct serstruct;
	void __user *user_arg = (void __user *)arg;

	switch (cmd) {
	case TIOCGSERIAL:
		memset(&serstruct, 0, sizeof(serstruct));
		serstruct.type = PORT_16654;
		serstruct.line = port->minor;
		serstruct.port = port->port_number;
		serstruct.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
		serstruct.xmit_fifo_size = kfifo_size(&port->write_fifo);
		serstruct.custom_divisor = 0;
		serstruct.baud_base = 460800;
		serstruct.close_delay = CLOSING_DELAY;
		serstruct.closing_wait = CLOSING_DELAY;

		if (copy_to_user(user_arg, &serstruct, sizeof(serstruct)))
			return -EFAULT;
		break;
	default:
		break;
	}

	return -ENOIOCTLCMD;
}

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.