commit 2d8f4447 upstream.

Do not use uninitialised termios data to determine when to configure the
device at open.

This also prevents stack data from leaking to userspace in the OOM error
path.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
[bwh: Backported to 3.2: tty_struct::termios is a pointer, not a struct]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>