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: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Peter Hurley 2014-10-16 15:33:22 -04:00 committed by Greg Kroah-Hartman
parent a361858da3
commit 6460fbbf47
2 changed files with 4 additions and 2 deletions

View File

@ -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,

View File

@ -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.
*/