linux-kernel - Re: [PATCH 1/2] KVM: vmx/pmu: Fix dummy check if lbr

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:   Tue, 23 Feb 2021 18:19:43 +0100
From:   Paolo Bonzini <pbonzini@...hat.com>
To:     Sean Christopherson <seanjc@...gle.com>,
        Like Xu <like.xu@...ux.intel.com>
Cc:     Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        x86@...nel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/2] KVM: vmx/pmu: Fix dummy check if lbr_desc->event is
 created

On 23/02/21 18:15, Sean Christopherson wrote:
> If event
> creation fails in that flow, I would think KVM would do its best to create an
> event in future runs without waiting for additional actions from the guest.
> 
> Also, this bug suggests there's a big gaping hole in the test coverage.  AFAICT,
> event contention would lead to a #GP crash in the host due to lbr_desc->event
> being dereferenced, no?

Yes, testing contention would use the tools/testing/selftests/kvm 
framework rather than just kvm-unit-tests.

Paolo