tty: Flush tty buffers after hardware shutdown

The line discipline buffer and the tty buffers must be flushed again
after hardware shutdown; otherwise, a brief window exists between the
ldisc flush in tty_port_close_start() and the subsequent
tty_port_shutdown(), during which more data could be received into the
tty buffers. A racing open might then be able to receive data from the
previous session.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Peter Hurley 2014-11-05 12:40:05 -05:00 committed by Greg Kroah-Hartman
parent 413ba63853
commit 3f40f5b2a2

View File

@ -520,6 +520,7 @@ void tty_port_close_end(struct tty_port *port, struct tty_struct *tty)
{
unsigned long flags;
tty_ldisc_flush(tty);
tty->closing = 0;
spin_lock_irqsave(&port->lock, flags);