Patch "serial: ifx6x60: fix use-after-free on module unload" has been added to the 4.4-stable tree

Patch "serial: ifx6x60: fix use-after-free on module unload" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    serial: ifx6x60: fix use-after-free on module unload

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     serial-ifx6x60-fix-use-after-free-on-module-unload.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 1e948479b3d63e3ac0ecca13cbf4921c7d17c168 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Wed, 26 Apr 2017 12:24:21 +0200
Subject: serial: ifx6x60: fix use-after-free on module unload

From: Johan Hovold <johan@kernel.org>

commit 1e948479b3d63e3ac0ecca13cbf4921c7d17c168 upstream.

Make sure to deregister the SPI driver before releasing the tty driver
to avoid use-after-free in the SPI remove callback where the tty
devices are deregistered.

Fixes: 72d4724ea54c ("serial: ifx6x60: Add modem power off function in the platform reboot process")
Cc: Jun Chen <jun.d.chen@intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/tty/serial/ifx6x60.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/tty/serial/ifx6x60.c
+++ b/drivers/tty/serial/ifx6x60.c
@@ -1378,9 +1378,9 @@ static struct spi_driver ifx_spi_driver
 static void __exit ifx_spi_exit(void)
 {
 	/* unregister */
+	spi_unregister_driver(&ifx_spi_driver);
 	tty_unregister_driver(tty_drv);
 	put_tty_driver(tty_drv);
-	spi_unregister_driver(&ifx_spi_driver);
 	unregister_reboot_notifier(&ifx_modem_reboot_notifier_block);
 }
 


Patches currently in stable-queue which might be from johan@kernel.org are

queue-4.4/serial-ifx6x60-fix-use-after-free-on-module-unload.patch