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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 25157C433FE for ; Thu, 7 Apr 2022 01:12:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=rUsrL1IhhhXPj0Frq0uO5MKFJdW9it/y4WfurCH8bLs=; b=R/7M9eovflkM4T YB/EDvz+pNKg2n5XdSwyjEGP/R4msy92LUXUg8UAWGF8yn6tmIWi1nhCrmW2KgAm++uIs80g066L1 tCYfjrFlpLmRNQzGTTbwH/n8lvDTOj31qg2j4r7r1B7u+1r/FU6fZ7GNjlkhvR1qyxZJdrB4vb14C mrncBP5EOnWYzay1i7csL7hbWVIcpiQcXICgPmXzlMcQtnRSzmnQNpTgPHfoG+U1m6CKjTOVfXKPp bB428QXme9ABKOAuuC9BMClcC8Ww1/x+I1NTVzalygu/kSTu363ksqIPU5YieU5zjy0rNes8dmnuW gICm2moyVUSSv3zM6abQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ncGfw-008U5j-Ex; Thu, 07 Apr 2022 01:11:04 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ncGfn-008U0j-Bo for linux-arm-kernel@lists.infradead.org; Thu, 07 Apr 2022 01:10:56 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E3BFB61DB8; Thu, 7 Apr 2022 01:10:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7E708C385BC; Thu, 7 Apr 2022 01:10:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1649293854; bh=adLbLelwA0eTEMAxwIejJevJ/N5XHRVQmd9kn8IfuU0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LUEh62kLR9cvfqWiq+LT6FL9GenB5z53kI3/tKxRHFicUUPT5fGdI6yxO1j+VQXi4 hodTsfe5CgNTdSu87Xjr6bMufm/HBOpWtPW+zfG+oZhRyLdeY2sA0c5IAcYS5/7WXm uCOz41I4lyEubGGnfRK1g+4Rwii84YDp3A6j2AZo6A6ZrYaUzG3djtSliscunX+ioS HrWXkmbsN59QHS0Ff9iK5F+GrlMrJ0mrXChZ4bfdySU8Wm7EQhdGW0dRjzcwSoG3SY jhzFjzp2N8suLkUGronHbM5+3ehymYgyxkFotLpmEykibpK8/7ikt91gjW1clA/9AW 40yLg+qf3Spog== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Andre Przywara , Jernej Skrabec , Alexandre Belloni , Sasha Levin , a.zummo@towertech.it, wens@csie.org, samuel@sholland.org, linux-rtc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev Subject: [PATCH AUTOSEL 5.17 13/31] rtc: sun6i: Fix time overflow handling Date: Wed, 6 Apr 2022 21:10:11 -0400 Message-Id: <20220407011029.113321-13-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220407011029.113321-1-sashal@kernel.org> References: <20220407011029.113321-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220406_181055_522888_3B6C508B X-CRM114-Status: GOOD ( 16.92 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Andre Przywara [ Upstream commit 9f6cd82eca7e91a0d0311242a87c6aa3c2737968 ] Using "unsigned long" for UNIX timestamps is never a good idea, and comparing the value of such a variable against U32_MAX does not do anything useful on 32-bit systems. Use the proper time64_t type when dealing with timestamps, and avoid cutting down the time range unnecessarily. This also fixes the flawed check for the alarm time being too far into the future. The check for this condition is actually somewhat theoretical, as the RTC counts till 2033 only anyways, and 2^32 seconds from now is not before the year 2157 - at which point I hope nobody will be using this hardware anymore. Signed-off-by: Andre Przywara Reviewed-by: Jernej Skrabec Signed-off-by: Alexandre Belloni Link: https://lore.kernel.org/r/20220211122643.1343315-4-andre.przywara@arm.com Signed-off-by: Sasha Levin --- drivers/rtc/rtc-sun6i.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/drivers/rtc/rtc-sun6i.c b/drivers/rtc/rtc-sun6i.c index 711832c758ae..bcc0c2ce4b4e 100644 --- a/drivers/rtc/rtc-sun6i.c +++ b/drivers/rtc/rtc-sun6i.c @@ -138,7 +138,7 @@ struct sun6i_rtc_dev { const struct sun6i_rtc_clk_data *data; void __iomem *base; int irq; - unsigned long alarm; + time64_t alarm; struct clk_hw hw; struct clk_hw *int_osc; @@ -510,10 +510,8 @@ static int sun6i_rtc_setalarm(struct device *dev, struct rtc_wkalrm *wkalrm) struct sun6i_rtc_dev *chip = dev_get_drvdata(dev); struct rtc_time *alrm_tm = &wkalrm->time; struct rtc_time tm_now; - unsigned long time_now = 0; - unsigned long time_set = 0; - unsigned long time_gap = 0; - int ret = 0; + time64_t time_now, time_set; + int ret; ret = sun6i_rtc_gettime(dev, &tm_now); if (ret < 0) { @@ -528,9 +526,7 @@ static int sun6i_rtc_setalarm(struct device *dev, struct rtc_wkalrm *wkalrm) return -EINVAL; } - time_gap = time_set - time_now; - - if (time_gap > U32_MAX) { + if ((time_set - time_now) > U32_MAX) { dev_err(dev, "Date too far in the future\n"); return -EINVAL; } @@ -539,7 +535,7 @@ static int sun6i_rtc_setalarm(struct device *dev, struct rtc_wkalrm *wkalrm) writel(0, chip->base + SUN6I_ALRM_COUNTER); usleep_range(100, 300); - writel(time_gap, chip->base + SUN6I_ALRM_COUNTER); + writel(time_set - time_now, chip->base + SUN6I_ALRM_COUNTER); chip->alarm = time_set; sun6i_rtc_setaie(wkalrm->enabled, chip); -- 2.35.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel