Re: [PATCH v1 OPT1] driver core: Fix use-after-free and double free on glue directory

From: Greg KH
Date: Thu Jul 04 2019 - 01:41:33 EST


On Thu, Jul 04, 2019 at 08:57:53AM +1000, Benjamin Herrenschmidt wrote:
> On Wed, 2019-07-03 at 21:37 +0200, Greg KH wrote:
> > Ok, I guess I have to take this patch, as the other one is so bad :)
> >
> > But, I need a very large comment here saying why we are poking around in
> > a kref and why we need to do this, at the expense of anything else.
> >
> > So can you respin this patch with a comment here to help explain it so
> > we have a chance to understand it when we run across this line in 10
> > years?
>
> Also are we confident that an open dir on the glue dir from userspace
> won't keep the kref up ?

How do you "open" a directory which raises the kref?

thanks,

greg k-h