linux-kernel - Re: [PATCH v2 2/6] driver core: Add common support to skip probe for un-authorized devices

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: <20210930115243-mutt-send-email-mst@kernel.org>
Date:   Thu, 30 Sep 2021 11:59:04 -0400
From:   "Michael S. Tsirkin" <mst@...hat.com>
To:     Alan Stern <stern@...land.harvard.edu>
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@...ux.intel.com>,
        Borislav Petkov <bp@...en8.de>, x86@...nel.org,
        Bjorn Helgaas <bhelgaas@...gle.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        Andreas Noever <andreas.noever@...il.com>,
        Michael Jamet <michael.jamet@...el.com>,
        Yehezkel Bernat <YehezkelShB@...il.com>,
        "Rafael J . Wysocki" <rafael@...nel.org>,
        Mika Westerberg <mika.westerberg@...ux.intel.com>,
        Jonathan Corbet <corbet@....net>,
        Jason Wang <jasowang@...hat.com>,
        Dan Williams <dan.j.williams@...el.com>,
        Andi Kleen <ak@...ux.intel.com>,
        Kuppuswamy Sathyanarayanan <knsathya@...nel.org>,
        linux-kernel@...r.kernel.org, linux-pci@...r.kernel.org,
        linux-usb@...r.kernel.org,
        virtualization@...ts.linux-foundation.org
Subject: Re: [PATCH v2 2/6] driver core: Add common support to skip probe for
 un-authorized devices

On Thu, Sep 30, 2021 at 11:35:09AM -0400, Alan Stern wrote:
> On Thu, Sep 30, 2021 at 10:58:07AM -0400, Michael S. Tsirkin wrote:
> > On Thu, Sep 30, 2021 at 10:43:05AM -0400, Alan Stern wrote:
> > > I don't see any point in talking about "untrusted drivers".  If a 
> > > driver isn't trusted then it doesn't belong in your kernel.  Period.  
> > > When you load a driver into your kernel, you are implicitly trusting 
> > > it (aside from limitations imposed by security modules).
> > 
> > Trusting it to do what? Historically a ton of drivers did not
> > validate input from devices they drive. Most still don't.
> 
> Trusting it to behave properly (i.e., not destroy your system, among 
> other things).

I don't think the current mitigations under discussion here are about
keeping the system working. In fact most encrypted VM configs tend to
stop booting as a preferred way to handle security issues.

> The fact that many drivers haven't been trustworthy is beside the 
> point.  By loading them into your kernel, you are trusting them 
> regardless.  In the end, you may regret having done so.  :-(
> 
> Alan Stern



-- 
MST