linux-kernel - Re: [RFC PATCH 1/2] ipc: introduce obtaining a lockless ipc object

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 1 Mar 2013 17:14:56 -0800
From:	Linus Torvalds <torvalds@...ux-foundation.org>
To:	Davidlohr Bueso <davidlohr.bueso@...com>
Cc:	Rik van Riel <riel@...hat.com>,
	"Vinod, Chegu" <chegu_vinod@...com>,
	"Low, Jason" <jason.low2@...com>,
	linux-tip-commits@...r.kernel.org,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	"H. Peter Anvin" <hpa@...or.com>,
	Andrew Morton <akpm@...ux-foundation.org>, aquini@...hat.com,
	Michel Lespinasse <walken@...gle.com>,
	Ingo Molnar <mingo@...nel.org>,
	Larry Woodman <lwoodman@...hat.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Steven Rostedt <rostedt@...dmis.org>,
	Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [RFC PATCH 1/2] ipc: introduce obtaining a lockless ipc object

On Fri, Mar 1, 2013 at 4:16 PM, Davidlohr Bueso <davidlohr.bueso@...com> wrote:
>
> +struct kern_ipc_perm *ipc_obtain_object(struct ipc_ids *ids, int id)

This looks good..

> +struct kern_ipc_perm *ipc_obtain_object_check(struct ipc_ids *ids, int id)

The comment on ipc_checkid() says that it should only be called with
the lock held.

Which seems entirely bogus, and I think it's just stale. It's just
checking the same ipc->seq that is only set at allocation, so it won't
change, afaik.

So I *think* the above is ok, but I'd want people to look at that
comment and remove it if it is stale. And if it's not stale, think
about this.

               Linus
--
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/