linux-kernel - Re: /sys/devices/system/cpu/vulnerabilities/ doesn't show all known CPU vulnerabilities

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: <alpine.DEB.2.21.1908151054090.2241@nanos.tec.linutronix.de>
Date:   Thu, 15 Aug 2019 11:03:35 +0200 (CEST)
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Kernel User <linux-kernel@...eup.net>
cc:     LKML <linux-kernel@...r.kernel.org>, mhocko@...e.com,
        x86@...nel.org
Subject: Re: /sys/devices/system/cpu/vulnerabilities/ doesn't show all known
 CPU vulnerabilities

On Wed, 14 Aug 2019, Kernel User wrote:
> On Wed, 14 Aug 2019 09:04:57 +0200 Borislav Petkov wrote:
> 
> > IMO, what you want does not belong in sysfs but in documentation.
> 
> How would documentation (a fixed static text file) tell whether a
> particular system is vulnerable or not?
> 
> > I partially see your point that a table of sorts mapping all those CPU
> > vulnerability names to (possible) mitigations is needed for users
> > which would like to know whether they're covered, without having to
> > run some scripts from github,
> 
> Correct.
> 
> > but sysfs just ain't the place.
> 
> Then why is it currently used for some of the vulnerabilities?

It's used to denote vulnerability classes and their mitigations:

  - Spectre v1
  - Spectre v2
  - Meltdown
  - SSB
  - L1TF
  - MDS

We are not tracking subclasses and their individual CVEs. The sysfs
interface is accurate (including SMT state) and the mapping to subclasses
and CVEs can be done by user space tools if required.

Thanks,

	tglx