From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933807AbbIDNkw (ORCPT ); Fri, 4 Sep 2015 09:40:52 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:50107 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932908AbbIDNJn (ORCPT ); Fri, 4 Sep 2015 09:09:43 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Oleg Nesterov , "David S. Miller" , Luis Henriques Subject: [PATCH 3.16.y-ckt 066/130] net: pktgen: fix race between pktgen_thread_worker() and kthread_stop() Date: Fri, 4 Sep 2015 14:07:34 +0100 Message-Id: <1441372118-5933-67-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1441372118-5933-1-git-send-email-luis.henriques@canonical.com> References: <1441372118-5933-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt17 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Oleg Nesterov commit fecdf8be2d91e04b0a9a4f79ff06499a36f5d14f upstream. pktgen_thread_worker() is obviously racy, kthread_stop() can come between the kthread_should_stop() check and set_current_state(). Signed-off-by: Oleg Nesterov Reported-by: Jan Stancek Reported-by: Marcelo Leitner Signed-off-by: David S. Miller Signed-off-by: Luis Henriques --- net/core/pktgen.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/core/pktgen.c b/net/core/pktgen.c index 0e5719c20d61..0234ae038a62 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -3470,8 +3470,10 @@ static int pktgen_thread_worker(void *arg) pktgen_rem_thread(t); /* Wait for kthread_stop */ - while (!kthread_should_stop()) { + for (;;) { set_current_state(TASK_INTERRUPTIBLE); + if (kthread_should_stop()) + break; schedule(); } __set_current_state(TASK_RUNNING);