From patchwork Mon Apr 21 09:32:06 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 340703 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 5B211140078; Mon, 21 Apr 2014 19:33:52 +1000 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1WcAbk-0007ug-Bl; Mon, 21 Apr 2014 09:33:48 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1WcAa7-0006iq-Jn for kernel-team@lists.ubuntu.com; Mon, 21 Apr 2014 09:32:07 +0000 Received: from bl6-53-42.dsl.telepac.pt ([82.155.53.42] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1WcAa7-0003Bb-7d; Mon, 21 Apr 2014 09:32:07 +0000 From: Luis Henriques To: Oleg Nesterov Subject: [3.11.y.z extended stable] Patch "pid_namespace: pidns_get() should check task_active_pid_ns() != NULL" has been added to staging queue Date: Mon, 21 Apr 2014 10:32:06 +0100 Message-Id: <1398072726-17021-1-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.9.1 X-Extended-Stable: 3.11 Cc: kernel-team@lists.ubuntu.com, Linus Torvalds , ebiederm@xmission.com X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com This is a note to let you know that I have just added a patch titled pid_namespace: pidns_get() should check task_active_pid_ns() != NULL to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.11.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From a9acbb32982cc5c93bb646bb9135946adee347e3 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Wed, 2 Apr 2014 17:45:05 +0200 Subject: pid_namespace: pidns_get() should check task_active_pid_ns() != NULL commit d23082257d83e4bc89727d5aedee197e907999d2 upstream. pidns_get()->get_pid_ns() can hit ns == NULL. This task_struct can't go away, but task_active_pid_ns(task) is NULL if release_task(task) was already called. Alternatively we could change get_pid_ns(ns) to check ns != NULL, but it seems that other callers are fine. Signed-off-by: Oleg Nesterov Cc: Eric W. Biederman ebiederm@xmission.com> Signed-off-by: Linus Torvalds Signed-off-by: Luis Henriques --- kernel/pid_namespace.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) -- 1.9.1 diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index 601bb36..2a953de 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -312,7 +312,9 @@ static void *pidns_get(struct task_struct *task) struct pid_namespace *ns; rcu_read_lock(); - ns = get_pid_ns(task_active_pid_ns(task)); + ns = task_active_pid_ns(task); + if (ns) + get_pid_ns(ns); rcu_read_unlock(); return ns;