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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 51DA7C43463 for ; Fri, 18 Sep 2020 02:45:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0EB6623444 for ; Fri, 18 Sep 2020 02:45:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600397136; bh=fQJrEi1be1uFQFhv9+0guO+MFD8DKU7SupD2Oq/Rnck=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=yKIzgNSGI6DAlsYKQxVGjdvApydJlzI0J7z4125b1xycENrTKVIyoDvvCPcUX9w/3 rZ557w/WP1AUOcvJWCJj9fbsALb412lBPx0QmMGyMilJTwLw5nzfUhe0WAnba+w9hy 4OfJHAiSC3FCqsJ6dNWWThCke/vkGn8pyaOpHzIQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728058AbgIRCpf (ORCPT ); Thu, 17 Sep 2020 22:45:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:34754 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728422AbgIRCKS (ORCPT ); Thu, 17 Sep 2020 22:10:18 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E66F123A1E; Fri, 18 Sep 2020 02:10:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600395015; bh=fQJrEi1be1uFQFhv9+0guO+MFD8DKU7SupD2Oq/Rnck=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=y9D7KZKB/2Xhn5ALBDvAjOcfhaAqQrASdWa2SdQD/jHtk9CTbAmjCpBJwiydr5/5S y3YnOMhkxX7VCqvvs3IzZSRy9BlZ9GyQk7yw7v5WHEbtanfF9FGQ9FGYAQh9cCLrf4 lOXXjGDY2ZXbUhu27cMqVjKRfQsYOAjYQ6+sTa8k= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Alexandre Belloni , Sasha Levin , rtc-linux@googlegroups.com Subject: [PATCH AUTOSEL 4.19 110/206] rtc: sa1100: fix possible race condition Date: Thu, 17 Sep 2020 22:06:26 -0400 Message-Id: <20200918020802.2065198-110-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200918020802.2065198-1-sashal@kernel.org> References: <20200918020802.2065198-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 304d905cb23fd..56f625371735f 100644 --- a/drivers/rtc/rtc-sa1100.c +++ b/drivers/rtc/rtc-sa1100.c @@ -186,7 +186,6 @@ 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); @@ -215,15 +214,14 @@ 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(). @@ -272,6 +270,10 @@ 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) { -- 2.25.1