From patchwork Tue Sep 29 10:58:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 290966 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=-13.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 F3B48C4727C for ; Tue, 29 Sep 2020 12:05:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 83E19206CD for ; Tue, 29 Sep 2020 12:05:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601381133; bh=mQG+ER7t6O6YlEQAv1Ijbqu6u1XNyaxYMTu5QO3wwfw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tQdk6SC+TJ5rbZcHataSJmdfkjrA+yj8HCL82Br+P/QJ+YVxQXfUgTso3URH0EQ1a 8TDSBEt49m5qb2WxPnBuf70tDCnq1FlVqtHLREaNOYmy3lAxfz8rHRGYSgTOIQN5DU 0UFAyCOLU8GjdxkWpTjirgyN18hr3+Db8k4AKAxg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729203AbgI2MFc (ORCPT ); Tue, 29 Sep 2020 08:05:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:50310 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730269AbgI2Lhi (ORCPT ); Tue, 29 Sep 2020 07:37:38 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 ACF702074A; Tue, 29 Sep 2020 11:37:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601379450; bh=mQG+ER7t6O6YlEQAv1Ijbqu6u1XNyaxYMTu5QO3wwfw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KlCLfsa6NVd72KH9Gus9avX0BKHYGMT466dV6B56fWGHQBmyaUw+5iGOj8BK+H02P G3BC8smMdpBSjc4d4fdjOuegeGK4QutMd5UKOZZxHzbTXLvAtkkNSLe9K3/tIbfl8C bF9sN4iZZXWbmRNNpmLZUidx/lgKUnp3UU40KUCA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexandre Belloni , Sasha Levin Subject: [PATCH 5.4 169/388] rtc: sa1100: fix possible race condition Date: Tue, 29 Sep 2020 12:58:20 +0200 Message-Id: <20200929110018.662445756@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200929110010.467764689@linuxfoundation.org> References: <20200929110010.467764689@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Alexandre Belloni [ Upstream commit f2997775b111c6d660c32a18d5d44d37cb7361b1 ] Both RTC IRQs are 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 IRQs using devm_rtc_allocate_device, and use rtc_register_device to register the RTC device. Link: https://lore.kernel.org/r/20200306010146.39762-1-alexandre.belloni@bootlin.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin --- drivers/rtc/rtc-sa1100.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/drivers/rtc/rtc-sa1100.c b/drivers/rtc/rtc-sa1100.c index 86fa723b3b762..795273269d58e 100644 --- a/drivers/rtc/rtc-sa1100.c +++ b/drivers/rtc/rtc-sa1100.c @@ -182,7 +182,6 @@ static const struct rtc_class_ops sa1100_rtc_ops = { int sa1100_rtc_init(struct platform_device *pdev, struct sa1100_rtc *info) { - struct rtc_device *rtc; int ret; spin_lock_init(&info->lock); @@ -211,15 +210,14 @@ int sa1100_rtc_init(struct platform_device *pdev, struct sa1100_rtc *info) writel_relaxed(0, info->rcnr); } - rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &sa1100_rtc_ops, - THIS_MODULE); - if (IS_ERR(rtc)) { + info->rtc->ops = &sa1100_rtc_ops; + info->rtc->max_user_freq = RTC_FREQ; + + ret = rtc_register_device(info->rtc); + if (ret) { clk_disable_unprepare(info->clk); - return PTR_ERR(rtc); + return ret; } - info->rtc = rtc; - - rtc->max_user_freq = RTC_FREQ; /* Fix for a nasty initialization problem the in SA11xx RTSR register. * See also the comments in sa1100_rtc_interrupt(). @@ -268,6 +266,10 @@ static int sa1100_rtc_probe(struct platform_device *pdev) info->irq_1hz = irq_1hz; info->irq_alarm = irq_alarm; + info->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(info->rtc)) + return PTR_ERR(info->rtc); + ret = devm_request_irq(&pdev->dev, irq_1hz, sa1100_rtc_interrupt, 0, "rtc 1Hz", &pdev->dev); if (ret) {