linux-kernel - Re: [bug] block subsystem related crash with latest -git

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]

Message-ID: <20071017182206.GS15552@kernel.dk>
Date:	Wed, 17 Oct 2007 20:22:07 +0200
From:	Jens Axboe <jens.axboe@...cle.com>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	Ingo Molnar <mingo@...e.hu>, linux-kernel@...r.kernel.org,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [bug] block subsystem related crash with latest -git

On Wed, Oct 17 2007, Linus Torvalds wrote:
> 
> 
> On Wed, 17 Oct 2007, Jens Axboe wrote:
> > > 
> > > So avoiding the "sg_next()" on the last entry is pointless. 
> > 
> > Yeah, I didn't quite understand why if sg was valid, why dereferencing
> > *(sg + 1)->page would crap out :/
> 
> Actually, I take that back. If 'sg' is the last entry in a *non*linked 
> scatter-gather list (ie we don't use the last entry as a link, we actually 
> use it as a real SG entry), then "sg_next(sg)" will indeed access past the 
> end of the whole allocated array, and will access one past the end.
> 
> And with page-alloc debugging, that *will* blow up.
> 
> So I think your change to use "sg_next()" only when you actually need a 
> next pointer is the correct one after all.

Thanks, so I'm not totally crazy :-)

Can you just pull:

  git://git.kernel.dk/data/git/linux-2.6-block.git for-linus

then so we get those two pieces correct? Then the remaining issue seems
to be a new one that is biting Ingo elsewhere, at least we'll all be on
the same page then.

-- 
Jens Axboe

-
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/