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, 3 Nov 2017 09:59:58 +0100
From:   Michal Hocko <mhocko@...nel.org>
To:     Pavel Tatashin <pasha.tatashin@...cle.com>
Cc:     steven.sistare@...cle.com, daniel.m.jordan@...cle.com,
        akpm@...ux-foundation.org, mgorman@...hsingularity.net,
        linux-mm@...ck.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v1 1/1] mm: buddy page accessed before initialized

On Thu 02-11-17 12:10:39, Pavel Tatashin wrote:
> > > 
> > > Yes, but as I said, unfortunately memset(1) with CONFIG_VM_DEBUG does not
> > > catch this case. So, when CONFIG_VM_DEBUG is enabled kexec reboots without
> > > issues.
> > 
> > Can we make the init pattern to catch this?
> 
> Unfortunately, that is not easy: memset() gives us only one byte to play
> with, and if we use something else that will make CONFIG_VM_DEBUG
> unacceptably slow.

Why cannot we do something similar to the optimized struct page
initialization and write 8B at the time and fill up the size unaligned
chunk in 1B?
-- 
Michal Hocko
SUSE Labs

Powered by blists - more mailing lists