From b5325a02aa84c794cf520d6d68cae4b150988a32 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Fri, 10 May 2013 15:40:13 -0700 Subject: [PATCH] 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 Signed-off-by: Greg Kroah-Hartman --- drivers/char/ttyprintk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/char/ttyprintk.c b/drivers/char/ttyprintk.c index 4945bd3d18d0..d5d2e4a985aa 100644 --- a/drivers/char/ttyprintk.c +++ b/drivers/char/ttyprintk.c @@ -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";