diff options
| author | Peter Hurley <peter@hurleysoftware.com> | 2016-01-11 07:40:56 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-01-27 08:17:54 +0100 |
| commit | 6d27a63caad3f13e96cf065d2d96828c2006be6b (patch) | |
| tree | 9ac73a342940bb6c283e37f23e8384155c59dfb1 /drivers | |
| parent | tty: Fix unsafe ldisc reference via ioctl(TIOCGETD) (diff) | |
| download | linux-6d27a63caad3f13e96cf065d2d96828c2006be6b.tar.xz linux-6d27a63caad3f13e96cf065d2d96828c2006be6b.zip | |
n_tty: Fix unsafe reference to "other" ldisc
Although n_tty_check_unthrottle() has a valid ldisc reference (since
the tty core gets the ldisc ref in tty_read() before calling the line
discipline read() method), it does not have a valid ldisc reference to
the "other" pty of a pty pair. Since getting an ldisc reference for
tty->link essentially open-codes tty_wakeup(), just replace with the
equivalent tty_wakeup().
Cc: <stable@vger.kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/tty/n_tty.c | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index d9a5fc28fef4..b280abaad91b 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -269,16 +269,13 @@ static void n_tty_check_throttle(struct tty_struct *tty) static void n_tty_check_unthrottle(struct tty_struct *tty) { - if (tty->driver->type == TTY_DRIVER_TYPE_PTY && - tty->link->ldisc->ops->write_wakeup == n_tty_write_wakeup) { + if (tty->driver->type == TTY_DRIVER_TYPE_PTY) { if (chars_in_buffer(tty) > TTY_THRESHOLD_UNTHROTTLE) return; if (!tty->count) return; n_tty_kick_worker(tty); - n_tty_write_wakeup(tty->link); - if (waitqueue_active(&tty->link->write_wait)) - wake_up_interruptible_poll(&tty->link->write_wait, POLLOUT); + tty_wakeup(tty->link); return; } |