From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AE525C433FE for ; Thu, 17 Nov 2022 02:47:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234393AbiKQCrA (ORCPT ); Wed, 16 Nov 2022 21:47:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34388 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229939AbiKQCqx (ORCPT ); Wed, 16 Nov 2022 21:46:53 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC6963FBAC for ; Wed, 16 Nov 2022 18:46:49 -0800 (PST) Received: from kwepemi500016.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4NCPSK3l6cz15MkP; Thu, 17 Nov 2022 10:46:25 +0800 (CST) Received: from huawei.com (10.175.100.227) by kwepemi500016.china.huawei.com (7.221.188.220) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 17 Nov 2022 10:46:47 +0800 From: Shang XiaoJing To: , , , , CC: Subject: [PATCH] parisc: led: Fix potential null-ptr-deref in start_task() Date: Thu, 17 Nov 2022 10:45:14 +0800 Message-ID: <20221117024514.3620-1-shangxiaojing@huawei.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.175.100.227] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemi500016.china.huawei.com (7.221.188.220) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org start_task() calls create_singlethread_workqueue() and not checked the ret value, which may return NULL. And a null-ptr-deref may happen: start_task() create_singlethread_workqueue() # failed, led_wq is NULL queue_delayed_work() queue_delayed_work_on() __queue_delayed_work() # warning here, but continue __queue_work() # access wq->flags, null-ptr-deref Check the ret value and return -ENOMEM if it is NULL. Fixes: 3499495205a6 ("[PARISC] Use work queue in LED/LCD driver instead of tasklet.") Signed-off-by: Shang XiaoJing --- drivers/parisc/led.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/parisc/led.c b/drivers/parisc/led.c index d4be9d2ee74d..8bdc5e043831 100644 --- a/drivers/parisc/led.c +++ b/drivers/parisc/led.c @@ -137,6 +137,9 @@ static int start_task(void) /* Create the work queue and queue the LED task */ led_wq = create_singlethread_workqueue("led_wq"); + if (!led_wq) + return -ENOMEM; + queue_delayed_work(led_wq, &led_task, 0); return 0; -- 2.17.1