Re: [PATCH] uacce: fix concurrency of fops_open and uacce_remove

From: Greg Kroah-Hartman
Date: Mon Jun 20 2022 - 10:24:08 EST


On Mon, Jun 20, 2022 at 02:24:31PM +0100, Jean-Philippe Brucker wrote:
> >From c7c2b051ec19285bbb973f8a2a5e58bb5326e00e Mon Sep 17 00:00:00 2001
> From: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
> Date: Mon, 20 Jun 2022 10:10:41 +0100
> Subject: [PATCH] uacce: Tidy up locking
>
> The uacce driver must deal with a possible removal of the parent driver
> or device at any time.

No it should not, if the reference counting logic is properly set up.
The parent driver should correctly tear things down here.

> At the moment there are several issues that may
> result in use-after-free. Tidy up the locking to handle module removal.

I don't think you did that, as module removal should never happen if a
file descriptor is opened as I previously mentioned.

thanks,

greg k-h