tty: Fix tty_send_xchar() lock order inversion
authorPeter Hurley <peter@hurleysoftware.com>
Wed, 11 Nov 2015 13:03:54 +0000 (08:03 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 21 Nov 2015 00:19:54 +0000 (16:19 -0800)
commitee0c1a65cf95230d5eb3d9de94fd2ead9a428c67
tree2e2a14ae56458b5af323266ede1c4908be225f83
parent8005c49d9aea74d382f474ce11afbbc7d7130bec
tty: Fix tty_send_xchar() lock order inversion

The correct lock order is atomic_write_lock => termios_rwsem, as
established by tty_write() => n_tty_write().

Fixes: c274f6ef1c666 ("tty: Hold termios_rwsem for tcflow(TCIxxx)")
Reported-and-Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/tty_io.c
drivers/tty/tty_ioctl.c