linux-kernel - Re: [PATCH v3.4-rc5] block: iocontext->nr

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: <20120501180624.GW26595@google.com>
Date:	Tue, 1 May 2012 11:06:24 -0700
From:	Tejun Heo <tj@...nel.org>
To:	Jens Axboe <jaxboe@...ionio.com>
Cc:	Dave Jones <davej@...hat.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Sasha Levin <levinsasha928@...il.com>
Subject: Re: [PATCH v3.4-rc5] block: iocontext->nr_tasks should be
 initialized to one

On Tue, May 01, 2012 at 08:04:58PM +0200, Jens Axboe wrote:
> On 2012-05-01 18:17, Tejun Heo wrote:
> > create_task_io_context() left ioc->nr_tasks at zero; however, a newly
> > created ioc should have its nr_tasks initialized to one as it begins
> > attached to the task creating it.
> > 
> > This affects only CLONE_IO which currently doesn't seem to have any
> > actual user.  Sasha triggered WARN_ON_ONCE() in ioc_task_link() using
> > syscall fuzzer.  Even when it happens, the failure mode isn't critical
> > (blk-cgroup may allow attaching a CLONE_IO'd task to a cgroup when it
> > shouldn't and blkcg limits may behave weirdly).
> > 
> > Fix it by initializing it to one in create_task_io_context().
> > 
> > Signed-off-by: Tejun Heo <tj@...nel.org>
> > Reported-by: Sasha Levin <levinsasha928@...il.com>
> > LKML-Reference: <1335873936.16988.148.camel@...py>
> > Cc: stable@...r.kernel.org
> 
> BTW, this only affects for-3.5/core, it's not a mainline bug. So I've
> dropped the stable CC.

Ah, sorry about that.  Got confused which one got in when.

Thanks.

-- 
tejun
--
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/