linux-kernel - [PATCH 3.19.y-ckt 041/130] mei: prevent unloading mei hw modules while the device is opened.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1440713521-5906-42-git-send-email-kamal@canonical.com>
Date:	Thu, 27 Aug 2015 15:10:32 -0700
From:	Kamal Mostafa <kamal@...onical.com>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	kernel-team@...ts.ubuntu.com
Cc:	Tomas Winkler <tomas.winkler@...el.com>,
	Alexander Usyskin <alexander.usyskin@...el.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Kamal Mostafa <kamal@...onical.com>
Subject: [PATCH 3.19.y-ckt 041/130] mei: prevent unloading mei hw modules while the device is opened.

3.19.8-ckt6 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Tomas Winkler <tomas.winkler@...el.com>

commit 154322f47376fed6ab1e4b350aa45fffa15a61aa upstream.

chrdev_open() increases reference counter on cdev->owner. Instead of
assigning the owner to mei subsystem, the owner has to be set to the
underlaying HW module (mei_me or mei_txe), so once the device is opened
the HW module cannot be unloaded.

Signed-off-by: Tomas Winkler <tomas.winkler@...el.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@...el.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@...onical.com>
---
 drivers/misc/mei/main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index ae56ba6..f6b68e2 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -738,7 +738,7 @@ int mei_register(struct mei_device *dev, struct device *parent)
 	/* Fill in the data structures */
 	devno = MKDEV(MAJOR(mei_devt), dev->minor);
 	cdev_init(&dev->cdev, &mei_fops);
-	dev->cdev.owner = mei_fops.owner;
+	dev->cdev.owner = parent->driver->owner;
 
 	/* Add the device */
 	ret = cdev_add(&dev->cdev, devno, 1);
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/