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  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:	Fri, 19 Sep 2014 15:02:54 -0700
From:	Filipe Brandenburger <filbranden@...gle.com>
To:	Andy Lutomirski <luto@...capital.net>
Cc:	"H. Peter Anvin" <hpa@...or.com>, Greg Thelen <gthelen@...gle.com>,
	X86 ML <x86@...nel.org>, Thomas Gleixner <tglx@...utronix.de>,
	Michael Davidson <md@...gle.com>,
	Ingo Molnar <mingo@...hat.com>,
	Richard Larocque <rlarocque@...gle.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Linux API <linux-api@...r.kernel.org>
Subject: Re: [PATCH] x86/vdso: Add prctl to set per-process VDSO load

Hi Andy,

On Fri, Sep 19, 2014 at 12:27 PM, Andy Lutomirski <luto@...capital.net> wrote:
> I have this (special mapping tracking) 3/4 implemented.  I'm planning
> on making it fully functional for 64-bit programs and almost correct
> for 32-bit.  (You'll still crash if you have multiple threads, you use
> sysenter, and you remap the vdso, but I think that this is essentially
> unavoidable until someone lets mremap work on multiple vmas at once.)

In case that's useful, I was looking at swapping the vvar page by
changing the vm_special_mapping to change the pages array between the
actual vvar page and the zero page and using zap_page_range to force
the next access to go through a page fault that would remap it.

I didn't have all the details figured out (I was closer to 1/4 of it
implemented) but I didn't see any issues on 32-bit programs.

Let me know if you'd like to see some of my patches or if you think I
should keep working on them.

Cheers,
Filipe
--
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/

Powered by blists - more mailing lists