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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 87B5EC3F2D5 for ; Fri, 6 Mar 2020 07:34:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 652CC2072D for ; Fri, 6 Mar 2020 07:34:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726070AbgCFHeO (ORCPT ); Fri, 6 Mar 2020 02:34:14 -0500 Received: from relay4-d.mail.gandi.net ([217.70.183.196]:33007 "EHLO relay4-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725869AbgCFHeO (ORCPT ); Fri, 6 Mar 2020 02:34:14 -0500 X-Originating-IP: 86.202.105.35 Received: from localhost (lfbn-lyo-1-9-35.w86-202.abo.wanadoo.fr [86.202.105.35]) (Authenticated sender: alexandre.belloni@bootlin.com) by relay4-d.mail.gandi.net (Postfix) with ESMTPSA id EACAEE000E; Fri, 6 Mar 2020 07:34:11 +0000 (UTC) From: Alexandre Belloni To: Alessandro Zummo , Alexandre Belloni Cc: linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/3] rtc: ds1374: fix possible race condition Date: Fri, 6 Mar 2020 08:34:01 +0100 Message-Id: <20200306073404.56921-1-alexandre.belloni@bootlin.com> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-GND-Spam-Score: 400 X-GND-Status: SPAM Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The RTC IRQ is requested before the struct rtc_device is allocated, this may lead to a NULL pointer dereference in the IRQ handler. To fix this issue, allocating the rtc_device struct before requesting the RTC IRQ using devm_rtc_allocate_device, and use rtc_register_device to register the RTC device. Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-ds1374.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/rtc/rtc-ds1374.c b/drivers/rtc/rtc-ds1374.c index 6e9ddcd03992..cb18a11a3c76 100644 --- a/drivers/rtc/rtc-ds1374.c +++ b/drivers/rtc/rtc-ds1374.c @@ -620,6 +620,10 @@ static int ds1374_probe(struct i2c_client *client, if (!ds1374) return -ENOMEM; + ds1374->rtc = devm_rtc_allocate_device(&client->dev); + if (IS_ERR(ds1374->rtc)) + return PTR_ERR(ds1374->rtc); + ds1374->client = client; i2c_set_clientdata(client, ds1374); @@ -641,12 +645,11 @@ static int ds1374_probe(struct i2c_client *client, device_set_wakeup_capable(&client->dev, 1); } - ds1374->rtc = devm_rtc_device_register(&client->dev, client->name, - &ds1374_rtc_ops, THIS_MODULE); - if (IS_ERR(ds1374->rtc)) { - dev_err(&client->dev, "unable to register the class device\n"); - return PTR_ERR(ds1374->rtc); - } + ds1374->rtc->ops = &ds1374_rtc_ops; + + ret = rtc_register_device(ds1374->rtc); + if (ret) + return ret; #ifdef CONFIG_RTC_DRV_DS1374_WDT save_client = client; -- 2.24.1