[4.2.y-ckt stable] Patch "tty: vt, return error when con_startup fails" has been added to the 4.2.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    tty: vt, return error when con_startup fails

to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree 
which can be found at:

    https://git.launchpad.net/~canonical-kernel/linux/+git/linux-stable-ckt/log/?h=linux-4.2.y-queue

This patch is scheduled to be released in version 4.2.8-ckt12.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 4.2.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From a086f1a87ccac4fa9c464c0279aa8654636f310b Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby at suse.cz>
Date: Tue, 3 May 2016 17:05:54 +0200
Subject: tty: vt, return error when con_startup fails

commit 6798df4c5fe0a7e6d2065cf79649a794e5ba7114 upstream.

When csw->con_startup() fails in do_register_con_driver, we return no
error (i.e. 0). This was changed back in 2006 by commit 3e795de763.
Before that we used to return -ENODEV.

So fix the return value to be -ENODEV in that case again.

Fixes: 3e795de763 ("VT binding: Add binding/unbinding support for the VT console")
Signed-off-by: Jiri Slaby <jslaby at suse.cz>
Reported-by: "Dan Carpenter" <dan.carpenter at oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/tty/vt/vt.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 4462d16..cf20282 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -3583,9 +3583,10 @@ static int do_register_con_driver(const struct consw *csw, int first, int last)
 		goto err;

 	desc = csw->con_startup();
-
-	if (!desc)
+	if (!desc) {
+		retval = -ENODEV;
 		goto err;
+	}

 	retval = -EINVAL;

--
2.7.4