linux-kernel - Re: [PATCH] regmap: allow to disable all locking mechanisms

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 for Android: free password hash cracker in your pocket

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

Date:   Tue, 12 Dec 2017 12:18:31 +0000
From:   Mark Brown <broonie@...nel.org>
To:     Lars-Peter Clausen <lars@...afoo.de>
Cc:     Bartosz Golaszewski <brgl@...ev.pl>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] regmap: allow to disable all locking mechanisms

On Tue, Dec 12, 2017 at 12:42:47PM +0100, Lars-Peter Clausen wrote:
> On 12/06/2017 03:26 PM, Bartosz Golaszewski wrote:

> > + * @disable_locking: This regmap is either protected by external means or
> > + *                   is guaranteed not be be accessed from multiple threads.

> To guarantee this you need to make sure that a regmap instance with this
> flag set does not register a debugfs interface. debugfs file access happens
> from a userspace process and hence could (and probably) is in a different
> thread than the driver regmap access.

That's true, and the debugfs is world readable too so we can't just say
it's up to root to be sensible.

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)