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]
Date:   Mon, 15 Nov 2021 17:52:02 +0100
From:   Joerg Roedel <jroedel@...e.de>
To:     Sean Christopherson <seanjc@...gle.com>
Cc:     Marc Orr <marcorr@...gle.com>, Peter Gonda <pgonda@...gle.com>,
        Andy Lutomirski <luto@...nel.org>,
        Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...el.com>,
        Brijesh Singh <brijesh.singh@....com>,
        the arch/x86 maintainers <x86@...nel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        kvm list <kvm@...r.kernel.org>, linux-coco@...ts.linux.dev,
        linux-mm@...ck.org,
        Linux Crypto Mailing List <linux-crypto@...r.kernel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        Tom Lendacky <Thomas.Lendacky@....com>,
        "H. Peter Anvin" <hpa@...or.com>, Ard Biesheuvel <ardb@...nel.org>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        Sergio Lopez <slp@...hat.com>,
        "Peter Zijlstra (Intel)" <peterz@...radead.org>,
        Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
        David Rientjes <rientjes@...gle.com>,
        Dov Murik <dovmurik@...ux.ibm.com>,
        Tobin Feldman-Fitzthum <tobin@....com>,
        Michael Roth <Michael.Roth@....com>,
        Vlastimil Babka <vbabka@...e.cz>,
        "Kirill A . Shutemov" <kirill@...temov.name>,
        Andi Kleen <ak@...ux.intel.com>,
        Tony Luck <tony.luck@...el.com>,
        Sathyanarayanan Kuppuswamy 
        <sathyanarayanan.kuppuswamy@...ux.intel.com>
Subject: Re: [PATCH Part2 v5 00/45] Add AMD Secure Nested Paging (SEV-SNP)
 Hypervisor Support

On Sat, Nov 13, 2021 at 06:28:16PM +0000, Sean Christopherson wrote:
> Another issue is that the host kernel, which despite being "untrusted", absolutely
> should be acting in the best interests of the guest.  Allowing userspace to inject
> #VC, e.g. to attempt to attack the guest by triggering a spurious PVALIDATE, means
> the kernel is failing miserably on that front.

Well, no. The kernel is only a part of the hypervisor, KVM userspace is
another. It is possible today for the userspace part(s) to interact in bad
ways with the guest and trick or kill it. Allowing user-space to cause a
#VC in the guest is no different from that.

Regards,

-- 
Jörg Rödel
jroedel@...e.de

SUSE Software Solutions Germany GmbH
Maxfeldstr. 5
90409 Nürnberg
Germany
 
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ