linux-kernel - Re: [PATCH -v2 0/4] EFI 1:1 mapping

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:	Thu, 20 Jun 2013 19:17:31 +0100
From:	Matthew Garrett <mjg59@...f.ucam.org>
To:	Borislav Petkov <bp@...en8.de>
Cc:	James Bottomley <James.Bottomley@...senPartnership.com>,
	Ingo Molnar <mingo@...nel.org>,
	Linux EFI <linux-efi@...r.kernel.org>,
	Matt Fleming <matt@...sole-pimps.org>, X86 ML <x86@...nel.org>,
	LKML <linux-kernel@...r.kernel.org>, Borislav Petkov <bp@...e.de>
Subject: Re: [PATCH -v2 0/4] EFI 1:1 mapping

On Thu, Jun 20, 2013 at 08:14:45PM +0200, Borislav Petkov wrote:
> On Thu, Jun 20, 2013 at 07:10:15PM +0100, Matthew Garrett wrote:
> > Because Windows passes high addresses to SetVirtualAddressMap(), and
> > because if you can imagine firmware developers getting it wrong then
> > firmware developers will have got it wrong.
> 
> Can we reversely assume that if we'd used fixed high offsets, as hpa
> suggests, then it'll be fine? IOW, are any high addresses, even fixed
> ones, fine?

Windows actually seems to start at the top of address space and go down 
- this is what I get booting Windows 8 under kvm. It looks like very 
high addresses are fine, and we're currently using "low" high addresses, 
so I suspect we're fine pretty much anywhere in that range.

****** SetVirtualAddressMap
Type: 5
Physical Start: 3E878000
Virtual Start: FFFFFFFFFFBEB000
Number Of Pages: 15
Attributes: 800000000000000F
Type: 6
Physical Start: 3E88D000
Virtual Start: FFFFFFFFFFBD6000
Number Of Pages: 15
Attributes: 800000000000000F
Type: 5
Physical Start: 3FB22000
Virtual Start: FFFFFFFFFFBA6000
Number Of Pages: 30
Attributes: 800000000000000F
Type: 6
Physical Start: 3FB52000
Virtual Start: FFFFFFFFFFB82000
Number Of Pages: 24
Attributes: 800000000000000F
Type: 6
Physical Start: 3FFE0000
Virtual Start: FFFFFFFFFFB62000
Number Of Pages: 20


-- 
Matthew Garrett | mjg59@...f.ucam.org
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/