From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754908AbcI2NyQ (ORCPT ); Thu, 29 Sep 2016 09:54:16 -0400 Received: from mail-yb0-f193.google.com ([209.85.213.193]:36504 "EHLO mail-yb0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752596AbcI2NyG (ORCPT ); Thu, 29 Sep 2016 09:54:06 -0400 Date: Thu, 29 Sep 2016 15:54:02 +0200 From: Tejun Heo To: Dan Carpenter Cc: Li Zefan , Johannes Weiner , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH cgroup/for-4.6] cgroup: fix error handling regressions in proc_cgroup_show() and cgroup_release_agent() Message-ID: <20160929135402.GA32490@mtj.duckdns.org> References: <20160929092722.GA5513@mwanda> <20160929095836.GB24034@mtj.duckdns.org> <20160929132641.GP26713@mwanda> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160929132641.GP26713@mwanda> User-Agent: Mutt/1.7.0 (2016-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4c737b41de7f ("cgroup: make cgroup_path() and friends behave in the style of strlcpy()") broke error handling in proc_cgroup_show() and cgroup_release_agent() by not handling negative return values from cgroup_path_ns_locked(). Fix it. Reported-by: Dan Carpenter Signed-off-by: Tejun Heo --- kernel/cgroup.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 5e2e81a..a7f9fb4 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -5781,10 +5781,10 @@ int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns, if (cgroup_on_dfl(cgrp) || !(tsk->flags & PF_EXITING)) { retval = cgroup_path_ns_locked(cgrp, buf, PATH_MAX, current->nsproxy->cgroup_ns); - if (retval >= PATH_MAX) { + if (retval >= PATH_MAX) retval = -ENAMETOOLONG; + if (retval < 0) goto out_unlock; - } seq_puts(m, buf); } else { @@ -6069,7 +6069,7 @@ static void cgroup_release_agent(struct work_struct *work) spin_lock_irq(&css_set_lock); ret = cgroup_path_ns_locked(cgrp, pathbuf, PATH_MAX, &init_cgroup_ns); spin_unlock_irq(&css_set_lock); - if (ret >= PATH_MAX) + if (ret < 0 || ret >= PATH_MAX) goto out; argv[0] = agentbuf; -- 2.7.4