linux-ext4 - Re: [PATCH V3] fix bb_prealloc_list corruption due to wrong group locking

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:	Wed, 18 Mar 2009 11:17:09 -0500
From:	Eric Sandeen <sandeen@...hat.com>
To:	Frank Mayhar <fmayhar@...gle.com>
CC:	ext4 development <linux-ext4@...r.kernel.org>
Subject: Re: [PATCH V3] fix bb_prealloc_list corruption due to wrong group
 locking

Frank Mayhar wrote:
> On Mon, 2009-03-16 at 10:53 -0700, Frank Mayhar wrote: 
>> On Mon, 2009-03-16 at 12:48 -0500, Eric Sandeen wrote:
>>> Hi Frank - I don't *think* so just because deleted items are poisoned
>>> and I would expect that we'd trip over a bad pointer in the corrupted
>>> list item as the first indicator of trouble... but I could be wrong.
>>>
>>> I think you said you could reproduce it, right?  So certainly worth
>>> testing with this fix I suppose.
>> Yeah, we're working on doing that now.  We're not running with a lot of
>> debugging turned on so we may or may not actually fall over if we try to
>> traverse freed (or just wrong) list entries.  If it isn't the same race,
>> though, then there's still one lurking in this code and that would be a
>> hell of a coincidence.
> 
> FYI we're running now with this patch in both a test and a production
> environment and haven't (yet) seen the bitmap inconsistency we were
> encountering regularly.  So far we have over 18 hours of runtime.  So,
> despite the enormous coincidence, our problem appears to be due to the
> same cause.
> 
> Thanks for the fix, Eric!

Good deal; I'll just trust that it's fixed, and maybe at some point I'll
sort out how they're related ;)

Thanks,
-Eric
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html