linux-kernel - [PATCH 0/3] xen/pv: sanitize xen pv guest msr accesses

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-next>] [day] [month] [year] [list]

Date:   Mon, 26 Sep 2022 16:18:46 +0200
From:   Juergen Gross <jgross@...e.com>
To:     xen-devel@...ts.xenproject.org, x86@...nel.org,
        linux-kernel@...r.kernel.org, linux-doc@...r.kernel.org
Cc:     Juergen Gross <jgross@...e.com>,
        Boris Ostrovsky <boris.ostrovsky@...cle.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        "H. Peter Anvin" <hpa@...or.com>, Jonathan Corbet <corbet@....net>
Subject: [PATCH 0/3] xen/pv: sanitize xen pv guest msr accesses

Historically when running as Xen PV guest all MSR accesses have been
silently swallowing any GP faults, even when the kernel was using not
the *msr_safe() access functions.

Change that by making the behavior controllable via kernel config and
via a boot parameter.

This will help finding paths where MSRs are being accessed under Xen
which are not emulated by the hypervisor.

Juergen Gross (3):
  xen/pv: allow pmu msr accesses to cause GP
  xen/pv: refactor msr access functions to support safe and unsafe
    accesses
  xen/pv: support selecting safe/unsafe msr accesses

 .../admin-guide/kernel-parameters.txt         |  6 ++
 arch/x86/xen/Kconfig                          |  9 ++
 arch/x86/xen/enlighten_pv.c                   | 97 +++++++++++++------
 arch/x86/xen/pmu.c                            | 44 +++++----
 4 files changed, 110 insertions(+), 46 deletions(-)

-- 
2.35.3