From patchwork Tue Jul 10 11:49:13 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Pisati X-Patchwork-Id: 941943 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=canonical.com Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 41Q0qD2vnGz9s1B; Tue, 10 Jul 2018 21:49:27 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1fcr8w-00062n-4g; Tue, 10 Jul 2018 11:49:18 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.86_2) (envelope-from ) id 1fcr8u-00062K-H5 for kernel-team@lists.ubuntu.com; Tue, 10 Jul 2018 11:49:16 +0000 Received: from 1.general.ppisati.uk.vpn ([10.172.193.134] helo=canonical.com) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1fcr8u-0002li-7G for kernel-team@lists.ubuntu.com; Tue, 10 Jul 2018 11:49:16 +0000 From: Paolo Pisati To: kernel-team@lists.ubuntu.com Subject: [PATCH] uwb: properly check kthread_run return value Date: Tue, 10 Jul 2018 13:49:13 +0200 Message-Id: <1531223353-13437-2-git-send-email-paolo.pisati@canonical.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1531223353-13437-1-git-send-email-paolo.pisati@canonical.com> References: <1531223353-13437-1-git-send-email-paolo.pisati@canonical.com> X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 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" From: Andrey Konovalov uwbd_start() calls kthread_run() and checks that the return value is not NULL. But the return value is not NULL in case kthread_run() fails, it takes the form of ERR_PTR(-EINTR). Use IS_ERR() instead. Also add a check to uwbd_stop(). Signed-off-by: Andrey Konovalov Cc: stable Signed-off-by: Greg Kroah-Hartman (cherry picked from commit bbf26183b7a6236ba602f4d6a2f7cade35bba043) Signed-off-by: Paolo Pisati Acked-by: Stefan Bader Signed-off-by: Juerg Haefliger --- drivers/uwb/uwbd.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/uwb/uwbd.c b/drivers/uwb/uwbd.c index bdcb13c..5c98283 100644 --- a/drivers/uwb/uwbd.c +++ b/drivers/uwb/uwbd.c @@ -303,18 +303,22 @@ static int uwbd(void *param) /** Start the UWB daemon */ void uwbd_start(struct uwb_rc *rc) { - rc->uwbd.task = kthread_run(uwbd, rc, "uwbd"); - if (rc->uwbd.task == NULL) + struct task_struct *task = kthread_run(uwbd, rc, "uwbd"); + if (IS_ERR(task)) { + rc->uwbd.task = NULL; printk(KERN_ERR "UWB: Cannot start management daemon; " "UWB won't work\n"); - else + } else { + rc->uwbd.task = task; rc->uwbd.pid = rc->uwbd.task->pid; + } } /* Stop the UWB daemon and free any unprocessed events */ void uwbd_stop(struct uwb_rc *rc) { - kthread_stop(rc->uwbd.task); + if (rc->uwbd.task) + kthread_stop(rc->uwbd.task); uwbd_flush(rc); }