void __stop_tty(struct tty_struct *tty)
{
	if (tty->stopped)
		return;
	tty->stopped = 1;
	if (tty->ops->stop)
		tty->ops->stop(tty);
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.