[PATCH 4.1 088/123] mei: prevent unloading mei hw modules while the device is opened.

From: Greg Kroah-Hartman
Date: Sat Aug 08 2015 - 18:19:01 EST

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


From: Tomas Winkler <tomas.winkler@xxxxxxxxx>

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@xxxxxxxxx>
Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

drivers/misc/mei/main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -685,7 +685,7 @@ int mei_register(struct mei_device *dev,
/* 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);

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