linux-kernel - Re: [PATCH 2/3] KVM: Check validity of offset+length of gfn_to_pfn

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: <f80574d1bb81acefc43fe6e016c9e51e7cf754b3.camel@infradead.org>
Date: Wed, 20 Mar 2024 08:20:44 +0000
From: David Woodhouse <dwmw2@...radead.org>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini
 <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	syzbot+106a4f72b0474e1d1b33@...kaller.appspotmail.com, Paul Durrant
	 <paul@....org>
Subject: Re: [PATCH 2/3] KVM: Check validity of offset+length of
 gfn_to_pfn_cache prior to activation

On Tue, 2024-03-19 at 17:15 -0700, Sean Christopherson wrote:
> When activating a gfn_to_pfn_cache, verify that the offset+length is sane
> and usable before marking the cache active.  Letting __kvm_gpc_refresh()
> detect the problem results in a cache being marked active without setting
> the GPA (or any other fields), which in turn results in KVM trying to
> refresh a cache with INVALID_GPA.
> 
> Attempting to refresh a cache with INVALID_GPA isn't functionally
> problematic, but it runs afoul of the sanity check that exactly one of
> GPA or userspace HVA is valid, i.e. that a cache is either GPA-based or
> HVA-based.
> 
> Reported-by: syzbot+106a4f72b0474e1d1b33@...kaller.appspotmail.com
> Closes: https://lore.kernel.org/all/0000000000005fa5cc0613f1cebd@google.com
> Fixes: 721f5b0dda78 ("KVM: pfncache: allow a cache to be activated with a fixed (userspace) HVA")

Reviewed-by: David Woodhouse <dwmw@...zon.co.uk>


Download attachment "smime.p7s" of type "application/pkcs7-signature" (5965 bytes)