linux-kernel - Re: PROBLEM: memory corrupting bug, bisected to 6dda9d55

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:	Tue, 19 Oct 2010 07:59:10 +1100
From:	Benjamin Herrenschmidt <benh@...nel.crashing.org>
To:	Mel Gorman <mel@....ul.ie>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org,
	linux-mm@...ck.org, pacman@...h.dhis.org,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Christoph Lameter <cl@...ux.com>,
	Yinghai Lu <yinghai@...nel.org>
Subject: Re: PROBLEM: memory corrupting bug, bisected to 6dda9d55

On Wed, 2010-10-13 at 15:40 +0100, Mel Gorman wrote:
> 
> This is somewhat contrived but I can see how it might happen even on one
> CPU particularly if the L1 cache is virtual and is loose about checking
> physical tags.
> 
> > How sensitive/vulnerable is PPC32 to such things?
> > 
> 
> I can not tell you specifically but if the above scenario is in any way
> plausible, I believe it would depend on what sort of L1 cache the CPU
> has. Maybe this particular version has a virtual cache with no physical
> tagging and is depending on the OS not to make virtual aliasing mistakes.

Nah, ppc doesn't have problems with cache aliases, it all looks
physically tagged to the programmer (tho there's subtleties but none
that explains the reported behaviour).

Looks like real memory corruption to me.

Cheers,
Ben.


--
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/