staging/speakup: Use tty_ldisc_ref() for paste kworker

As the function documentation for tty_ldisc_ref_wait() notes, it is
only callable from a tty file_operations routine; otherwise there
is no guarantee the ref won't be NULL.

The key difference with the VT's paste_selection() is that is an ioctl,
where __speakup_paste_selection() is completely async kworker, kicked
off from interrupt context.

Fixes: 28a821c306 ("Staging: speakup: Update __speakup_paste_selection()
       tty (ab)usage to match vt")
Cc: <stable@vger.kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Peter Hurley 2016-01-10 22:40:58 -08:00 committed by Greg Kroah-Hartman
parent 6d27a63caa
commit f4f9edcf9b

View File

@ -142,7 +142,9 @@ static void __speakup_paste_selection(struct work_struct *work)
struct tty_ldisc *ld;
DECLARE_WAITQUEUE(wait, current);
ld = tty_ldisc_ref_wait(tty);
ld = tty_ldisc_ref(tty);
if (!ld)
goto tty_unref;
tty_buffer_lock_exclusive(&vc->port);
add_wait_queue(&vc->paste_wait, &wait);
@ -162,6 +164,7 @@ static void __speakup_paste_selection(struct work_struct *work)
tty_buffer_unlock_exclusive(&vc->port);
tty_ldisc_deref(ld);
tty_unref:
tty_kref_put(tty);
}