From patchwork Wed Apr 22 09:56:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 227142 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=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, 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 EAF99C55189 for ; Wed, 22 Apr 2020 10:45:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C9CF620787 for ; Wed, 22 Apr 2020 10:45:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587552337; bh=0rcL6w+U3QxTPUxJYsUdrnHmbxHPVlcjvRNL/c8lbPI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=JaudOyMSwzb/b1v+VjVw0RqIrDDK7pSjkU7UVQA5dminBaBXu3i/GlCd+Ftu9LmCP 7zWIs7bM/FPzTARPRZxKA5F7JAe3iRoCB4T90AuKLIrNv2CTjoPkpYS2h6Fi1pyCBN WlsfxyOYjQKC1nZcrYFEfhkWC6powVaOElXgnTkM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731747AbgDVKpa (ORCPT ); Wed, 22 Apr 2020 06:45:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:54404 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729907AbgDVKR6 (ORCPT ); Wed, 22 Apr 2020 06:17:58 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4DA842075A; Wed, 22 Apr 2020 10:17:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550677; bh=0rcL6w+U3QxTPUxJYsUdrnHmbxHPVlcjvRNL/c8lbPI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Kp3r4S8eeF/nocpZT+J7g0gCtiFbK6FwgDWAVMvn0qJeHw64WBoLLIp8kfJb4X6i+ bPUveJi9rRnaAntu4CeH5LfMi8zkeOIi1D//dzvO/PLBSZsy9MMjjEmPA8QOlkznaZ IhG3vejdPufwdewUduBoWEe3KICEBD9e5L88/xJI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexandre Belloni , Sasha Levin Subject: [PATCH 5.4 049/118] rtc: 88pm860x: fix possible race condition Date: Wed, 22 Apr 2020 11:56:50 +0200 Message-Id: <20200422095040.040537088@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095031.522502705@linuxfoundation.org> References: <20200422095031.522502705@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Alexandre Belloni [ Upstream commit 9cf4789e6e4673d0b2c96fa6bb0c35e81b43111a ] 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. Also remove the unnecessary error message as the core already prints the info. Link: https://lore.kernel.org/r/20200311223956.51352-1-alexandre.belloni@bootlin.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin --- drivers/rtc/rtc-88pm860x.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/rtc/rtc-88pm860x.c b/drivers/rtc/rtc-88pm860x.c index 4743b16a8d849..1526402e126b2 100644 --- a/drivers/rtc/rtc-88pm860x.c +++ b/drivers/rtc/rtc-88pm860x.c @@ -336,6 +336,10 @@ static int pm860x_rtc_probe(struct platform_device *pdev) info->dev = &pdev->dev; dev_set_drvdata(&pdev->dev, info); + info->rtc_dev = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(info->rtc_dev)) + return PTR_ERR(info->rtc_dev); + ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL, rtc_update_handler, IRQF_ONESHOT, "rtc", info); @@ -377,13 +381,11 @@ static int pm860x_rtc_probe(struct platform_device *pdev) } } - info->rtc_dev = devm_rtc_device_register(&pdev->dev, "88pm860x-rtc", - &pm860x_rtc_ops, THIS_MODULE); - ret = PTR_ERR(info->rtc_dev); - if (IS_ERR(info->rtc_dev)) { - dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret); + info->rtc_dev->ops = &pm860x_rtc_ops; + + ret = rtc_register_device(info->rtc_dev); + if (ret) return ret; - } /* * enable internal XO instead of internal 3.25MHz clock since it can