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: <20230705141741.xqvjddsoo5qgax63@linux.intel.com>
Date:   Wed, 5 Jul 2023 22:17:42 +0800
From:   Yu Zhang <yu.c.zhang@...ux.intel.com>
To:     David Stevens <stevensd@...omium.org>
Cc:     Sean Christopherson <seanjc@...gle.com>,
        Marc Zyngier <maz@...nel.org>,
        Michael Ellerman <mpe@...erman.id.au>,
        Peter Xu <peterx@...hat.com>,
        linux-arm-kernel@...ts.infradead.org, kvmarm@...ts.linux.dev,
        linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
        kvm@...r.kernel.org
Subject: Re: [PATCH v7 5/8] KVM: x86/mmu: Don't pass FOLL_GET to
 __kvm_follow_pfn

> > @@ -883,7 +884,7 @@ static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
> >   */
> >  static int FNAME(sync_spte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, int i)
> >  {
> > -	bool host_writable;
> > +	bool host_writable, is_refcounted;
> >  	gpa_t first_pte_gpa;
> >  	u64 *sptep, spte;
> >  	struct kvm_memory_slot *slot;
> > @@ -940,10 +941,12 @@ static int FNAME(sync_spte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, int
> >  	sptep = &sp->spt[i];
> >  	spte = *sptep;
> >  	host_writable = spte & shadow_host_writable_mask;
> > +	// TODO: is this correct?
> > +	is_refcounted = spte & SPTE_MMU_PAGE_REFCOUNTED;
> >  	slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
> >  	make_spte(vcpu, sp, slot, pte_access, gfn,
> >  		  spte_to_pfn(spte), spte, true, false,
> > -		  host_writable, &spte);
> > +		  host_writable, is_refcounted, &spte);
> 
> Could we restrict that a non-refcounted page shall not be used as shadow page?

Oh, sorry. It's not about shadow page. It's about guest page being
mapped as not refcounted. Silly me...

B.R.
Yu

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ