[ 140/171] rbd: drop dev reference on error in rbd_open()

Greg Kroah-Hartman
2013-01-15T23:24:51Z

From: Alex Elder <elder@inktank.com>

If a read-only rbd device is opened for writing in rbd_open(), it
returns without dropping the just-acquired device reference.

Fix this by moving the read-only check before getting the reference.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
(cherry picked from commit 340c7a2b2c9a2da640af28a8c196356484ac8b50)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/block/rbd.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -250,13 +250,12 @@ static int rbd_open(struct block_device
{
struct rbd_device *rbd_dev = bdev->bd_disk->private_data;

- rbd_get_dev(rbd_dev);
-
- set_device_ro(bdev, rbd_dev->read_only);
-
if ((mode & FMODE_WRITE) && rbd_dev->read_only)
return -EROFS;

+ rbd_get_dev(rbd_dev);
+ set_device_ro(bdev, rbd_dev->read_only);
+
return 0;
}