From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754893AbaKXUGo (ORCPT ); Mon, 24 Nov 2014 15:06:44 -0500 Received: from mx1.redhat.com ([209.132.183.28]:43598 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754353AbaKXUGm (ORCPT ); Mon, 24 Nov 2014 15:06:42 -0500 Date: Mon, 24 Nov 2014 21:06:29 +0100 From: Oleg Nesterov To: Andrew Morton Cc: Aaron Tomlin , "Eric W. Biederman" , Pavel Emelyanov , Serge Hallyn , Sterling Alexander , linux-kernel@vger.kernel.org Subject: [PATCH 2/2] exit: pidns: alloc_pid() leaks pid_namespace if child_reaper is exiting Message-ID: <20141124200629.GA21009@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20141124200602.GA20575@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org alloc_pid() does get_pid_ns() beforehand but forgets to put_pid_ns() if it fails because disable_pid_allocation() was called by the exiting child_reaper. We can move get_pid_ns() down to successful return. While at it, simplify/cleanup the "goto out" mess, no need to confuse the success/error return paths. Signed-off-by: Oleg Nesterov --- kernel/pid.c | 7 +++---- 1 files changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/pid.c b/kernel/pid.c index 9b9a266..dfc2f3b 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -320,7 +320,6 @@ struct pid *alloc_pid(struct pid_namespace *ns) goto out_free; } - get_pid_ns(ns); atomic_set(&pid->count, 1); for (type = 0; type < PIDTYPE_MAX; ++type) INIT_HLIST_HEAD(&pid->tasks[type]); @@ -336,7 +335,7 @@ struct pid *alloc_pid(struct pid_namespace *ns) } spin_unlock_irq(&pidmap_lock); -out: + get_pid_ns(ns); return pid; out_unlock: @@ -346,8 +345,8 @@ out_free: free_pidmap(pid->numbers + i); kmem_cache_free(ns->pid_cachep, pid); - pid = NULL; - goto out; +out: + return NULL; } void disable_pid_allocation(struct pid_namespace *ns) -- 1.5.5.1