Commit b5325a02 authored May 10, 2013 by Darrick J. Wong Committed by Greg Kroah-Hartman May 21, 2013

ttyprintk: Fix NULL pointer deref by setting tty_port ops after initializing port

tty_port_init() zeroes out the tty port, which means that we have to set the
ops pointer /after/, not before this call. Otherwise, tty_port_open will crash
when it tries to deref ops, which is now a NULL pointer.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 89fb9e7c

drivers/char/ttyprintk.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -179,7 +179,6 @@ static int __init ttyprintk_init(void)
		{
		int ret = -ENOMEM;

		tpk_port.port.ops = &null_ops;
		mutex_init(&tpk_port.port_write_mutex);

		ttyprintk_driver = tty_alloc_driver(1,
		@@ -190,6 +189,7 @@ static int __init ttyprintk_init(void)
		return PTR_ERR(ttyprintk_driver);

		tty_port_init(&tpk_port.port);
		tpk_port.port.ops = &null_ops;

		ttyprintk_driver->driver_name = "ttyprintk";
		ttyprintk_driver->name = "ttyprintk";