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Date:   Fri, 19 Aug 2022 09:06:27 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Abhishek Shah <abhishek.shah@columbia.edu>
Cc:     jirislaby@kernel.org, linux-kernel@vger.kernel.org,
        bjohannesmeyer@gmail.com, jakobkoschel@gmail.com,
        xiam0nd.tong@gmail.com, Gabriel Ryan <gabe@cs.columbia.edu>
Subject: Re: data-race in set_console / vt_ioctl
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References: <CAEHB249P1XurGDtvfjzkEzP4qWEaL6FG4ENM=PYjk7-JZfnKrQ@mail.gmail.com>
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On Thu, Aug 18, 2022 at 09:17:00PM -0400, Abhishek Shah wrote:
> Hi all,
> 
> We found a data race involving the *vt_dont_switch* variable. Upon further
> investigation, we see that this racing variable controls whether the
> callbacks will be scheduled in the console (see here
> <https://elixir.bootlin.com/linux/v5.18-rc5/source/drivers/tty/vt/vt.c#L3032>),
> but we are not sure of its security implications. Please let us know what
> you think.

Again, any patch that you might have to resolve this would be great, as
that's the easiest thing to review.

thanks,

greg k-h