linux-kernel - Re: [RFC PATCH] module: Introduce module unload taint tracking

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]

Message-ID: <YbOIZOsiOarBtLxF@bombadil.infradead.org>
Date:   Fri, 10 Dec 2021 09:03:32 -0800
From:   Luis Chamberlain <mcgrof@...nel.org>
To:     Petr Mladek <pmladek@...e.com>
Cc:     Aaron Tomlin <atomlin@...hat.com>,
        Christoph Lameter <cl@...ux.com>,
        Miroslav Benes <mbenes@...e.cz>,
        Andrew Morton <akpm@...ux-foundation.org>, jeyu@...nel.org,
        linux-kernel@...r.kernel.org, linux-modules@...r.kernel.org,
        atomlin@...mlin.com
Subject: Re: [RFC PATCH] module: Introduce module unload taint tracking

On Fri, Dec 10, 2021 at 11:00:52AM +0100, Petr Mladek wrote:
> Please, do not remove records that a module was removed. IMHO, it
> might be useful to track all removed module, including the non-tainted
> ones.

Then we'd need two features. One modules removed, and another which
limits this to only tainted modules. On kernel-ci systems where I
try to reproduce issues with fstests or blktests I might be unloading
a module 10,000 times, and so for those systems I'd like to disable
the tracking of all modules removed, otherwise we'd end up with
-ENOMEM eventually.

> Module removal is always tricky and not much tested.

It is tricky but I have been trying to correct issues along that path
and given that fstests and blktests uses it heavily I want to start
dispelling the false narrative that this is not a common use case.

> The tain flags might be just shown as extra information in the output.

Yes!

  Luis