Re: [PATCH v2] block: Fix use-after-free in blkdev_get()

From: Jan Kara
Date: Fri Jun 05 2020 - 10:42:40 EST


On Fri 05-06-20 12:43:54, Dan Carpenter wrote:
> I wonder if maybe the best fix is to re-add the "if (!res) " check back
> to blkdev_get().

Well, it won't be that simple since we need to call bd_abort_claiming()
under bdev->bd_mutex. And the fact that __blkdev_get() frees the reference
you pass to it is somewhat subtle and surprising so I think we are better
off getting rid of that.

Honza
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR