linux-kernel - Re: [PATCH] kcsan, debugfs: Move debugfs file creation out of early init

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 3 Mar 2021 10:57:41 +0100
From:   Greg KH <gregkh@...uxfoundation.org>
To:     Marco Elver <elver@...gle.com>
Cc:     rafael@...nel.org, paulmck@...nel.org, dvyukov@...gle.com,
        glider@...gle.com, andreyknvl@...gle.com,
        kasan-dev@...glegroups.com, linux-kernel@...r.kernel.org,
        stable <stable@...r.kernel.org>
Subject: Re: [PATCH] kcsan, debugfs: Move debugfs file creation out of early
 init

On Wed, Mar 03, 2021 at 10:38:45AM +0100, Marco Elver wrote:
> Commit 56348560d495 ("debugfs: do not attempt to create a new file
> before the filesystem is initalized") forbids creating new debugfs files
> until debugfs is fully initialized. This breaks KCSAN's debugfs file
> creation, which happened at the end of __init().

How did it "break" it?  The files shouldn't have actually been created,
right?

> There is no reason to create the debugfs file during early
> initialization. Therefore, move it into a late_initcall() callback.
> 
> Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
> Cc: "Rafael J. Wysocki" <rafael@...nel.org>
> Cc: stable <stable@...r.kernel.org>
> Fixes: 56348560d495 ("debugfs: do not attempt to create a new file before the filesystem is initalized")
> Signed-off-by: Marco Elver <elver@...gle.com>
> ---
> I've marked this for 'stable', since 56348560d495 is also intended for
> stable, and would subsequently break KCSAN in all stable kernels where
> KCSAN is available (since 5.8).

No objection from me, just odd that this actually fixes anything :)

Reviewed-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>