linux-kernel - Re: [PATCH 1/8] stop_machine: cpu_stopper

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: <20151117175309.GA16154@redhat.com>
Date:	Tue, 17 Nov 2015 18:53:09 +0100
From:	Oleg Nesterov <oleg@...hat.com>
To:	Tejun Heo <tj@...nel.org>
Cc:	Ingo Molnar <mingo@...nel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	Milos Vyletel <milos@...hat.com>,
	Prarit Bhargava <prarit@...hat.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/8] stop_machine: cpu_stopper_thread() must check done
	!= NULL

On 11/16, Tejun Heo wrote:
>
> On Sun, Nov 15, 2015 at 08:33:11PM +0100, Oleg Nesterov wrote:
> > stop_one_cpu_nowait(fn) will crash the kernel if the callback returns
> > nonzero, work->done == NULL in this case.
> >
> > This needs more cleanups, cpu_stop_signal_done() is called right after
> > we check done != NULL and it does the same check.
> >
> > Signed-off-by: Oleg Nesterov <oleg@...hat.com>
>
> Acked-by: Tejun Heo <tj@...nel.org>

Thanks!

> cc stable?

Yes, I was going to add -stable initially. And perhaps this makes sense
anyway, the patch is really trivial.

OTOH I have checked the history, none of cpu_stop_signal_done's callbacks
ever returned non-zero, so I decided to not spam -stable.

Oleg.

--
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/