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 for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Wed, 24 Mar 2010 15:28:54 -0600
From:	Jonathan Corbet <corbet@....net>
To:	Andrea Arcangeli <aarcange@...hat.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Mel Gorman <mel@....ul.ie>,
	Christoph Lameter <cl@...ux-foundation.org>,
	Adam Litke <agl@...ibm.com>, Avi Kivity <avi@...hat.com>,
	David Rientjes <rientjes@...gle.com>,
	Minchan Kim <minchan.kim@...il.com>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Rik van Riel <riel@...hat.com>, linux-kernel@...r.kernel.org,
	linux-mm@...ck.org
Subject: Re: [PATCH 07/11] Memory compaction core

On Wed, 24 Mar 2010 22:19:24 +0100
Andrea Arcangeli <aarcange@...hat.com> wrote:

> > > It's a bit strange to test this when we're about to oops anyway.  The
> > > oops will tell us the same thing.  
> > 
> > ...except that we've seen a fair number of null pointer dereference
> > exploits that have told us something altogether different.  Are we
> > *sure* we don't want to test for null pointers...?  
> 
> Examples? Maybe WARN_ON != oops, but VM_BUG_ON still an oops that is
> and without serial console it would go lost too. I personally don't
> see how it's needed.

I don't quite understand the question; are you asking for examples of
exploits?

	http://lwn.net/Articles/347006/
	http://lwn.net/Articles/360328/
	http://lwn.net/Articles/342330/
	...

As to whether this particular test makes sense, I don't know.  But the
idea that we never need to test about-to-be-dereferenced pointers for
NULL does worry me a bit.

jon
--
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