linux-kernel - Re: [PATCH 1/2] cgroup: no need to check css refs for release notification

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] [day] [month] [year] [list]

Date:	Mon, 4 Mar 2013 10:05:08 -0800
From:	Tejun Heo <tj@...nel.org>
To:	Li Zefan <lizefan@...wei.com>
Cc:	LKML <linux-kernel@...r.kernel.org>,
	cgroups <cgroups@...r.kernel.org>
Subject: Re: [PATCH 1/2] cgroup: no need to check css refs for release
 notification

On Fri, Mar 01, 2013 at 03:06:07PM +0800, Li Zefan wrote:
> We no longer fail rmdir() when there're still css refs, so we don't
> need to check css refs in check_for_release().
> 
> This also voids a bug. cgroup_has_css_refs() accesses subsys[i]
> without cgroup_mutex, so it can race with cgroup_unload_subsys().
> 
> cgroup_has_css_refs()
> ...
>   if (ss == NULL || ss->root != cgrp->root)
> 
> if ss pointers to net_cls_subsys, and cls_cgroup module is unloaded
> right after the former check but before the latter, the memory that
> net_cls_subsys resides has become invalid.
> 
> Signed-off-by: Li Zefan <lizefan@...wei.com>

Applied to cgroup/for-3.10.

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/