Commit 6460fbbf authored by Peter Hurley's avatar Peter Hurley Committed by Greg Kroah-Hartman
Browse files

tty: WARN for attempted set_termios() of pty master 



The pty master's termios should never be set; currently, all code
paths which call the driver's set_termios() method ensure that the
pty slave's termios is being set.

Signed-off-by: default avatarPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: default avatarAlan Cox <alan@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent a361858d

drivers/tty/pty.c

+0 −2
Original line number Diff line number Diff line
@@ -477,7 +477,6 @@ static const struct tty_operations master_pty_ops_bsd = { 
	.flush_buffer = pty_flush_buffer,

	.chars_in_buffer = pty_chars_in_buffer,

	.unthrottle = pty_unthrottle,

	.set_termios = pty_set_termios,

	.ioctl = pty_bsd_ioctl,

	.cleanup = pty_cleanup,

	.resize = pty_resize,
@@ -654,7 +653,6 @@ static const struct tty_operations ptm_unix98_ops = { 
	.flush_buffer = pty_flush_buffer,

	.chars_in_buffer = pty_chars_in_buffer,

	.unthrottle = pty_unthrottle,

	.set_termios = pty_set_termios,

	.ioctl = pty_unix98_ioctl,

	.resize = pty_resize,

	.shutdown = pty_unix98_shutdown,

drivers/tty/tty_ioctl.c

+4 −0
Original line number Diff line number Diff line
@@ -528,6 +528,8 @@ EXPORT_SYMBOL(tty_termios_hw_change); 
 *	is a bit of layering violation here with n_tty in terms of the

 *	internal knowledge of this function.

 *

 *	A master pty's termios should never be set.

 *

 *	Locking: termios_rwsem

 */
@@ -537,6 +539,8 @@ int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios) 
	struct tty_ldisc *ld;

	unsigned long flags;



	WARN_ON(tty->driver->type == TTY_DRIVER_TYPE_PTY &&

		tty->driver->subtype == PTY_TYPE_MASTER);

	/*

	 *	Perform the actual termios internal changes under lock.

	 */