Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754108Ab0AZOu3 (ORCPT ); Tue, 26 Jan 2010 09:50:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753327Ab0AZOu2 (ORCPT ); Tue, 26 Jan 2010 09:50:28 -0500 Received: from e2.ny.us.ibm.com ([32.97.182.142]:38884 "EHLO e2.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752787Ab0AZOu2 (ORCPT ); Tue, 26 Jan 2010 09:50:28 -0500 Date: Tue, 26 Jan 2010 08:50:22 -0600 From: "Serge E. Hallyn" To: Li Zefan Cc: Andrew Morton , "containers@lists.osdl.org" , Paul Menage , LKML Subject: Re: [PATCH 1/2] cgroups: Fix to return errno in a failure path Message-ID: <20100126145022.GA6224@us.ibm.com> References: <4B5EA4EC.8020700@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4B5EA4EC.8020700@cn.fujitsu.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1780 Lines: 55 Quoting Li Zefan (lizf@cn.fujitsu.com): > In cgroup_create(), if alloc_css_id() returns failure, the errno > is not propagated to userspace, so mkdir will fail silently. > > To trigger this bug, we mount blkio (or memory subsystem), and > create more then 65534 cgroups. (The number of cgroups is limited > to 65535 if a subsystem has use_id == 1) > > # mount -t cgroup -o blkio xxx /mnt > # for ((i = 0; i < 65534; i++)); do mkdir /mnt/$i; done > # mkdir /mnt/65534 > (should return ENOSPC) > # > > Signed-off-by: Li Zefan Yup. Acked-by: Serge Hallyn > --- > cgroup.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > --- a/kernel/cgroup.c.orig 2010-01-19 16:37:37.000000000 +0800 > +++ a/kernel/cgroup.c 2010-01-19 16:39:07.000000000 +0800 > @@ -3279,14 +3279,17 @@ static long cgroup_create(struct cgroup > > for_each_subsys(root, ss) { > struct cgroup_subsys_state *css = ss->create(ss, cgrp); > + > if (IS_ERR(css)) { > err = PTR_ERR(css); > goto err_destroy; > } > init_cgroup_css(css, ss, cgrp); > - if (ss->use_id) > - if (alloc_css_id(ss, parent, cgrp)) > + if (ss->use_id) { > + err = alloc_css_id(ss, parent, cgrp); > + if (err) > goto err_destroy; > + } > /* At error, ->destroy() callback has to free assigned ID. */ > } > > _______________________________________________ > Containers mailing list > Containers@lists.linux-foundation.org > https://lists.linux-foundation.org/mailman/listinfo/containers -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/