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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 05279C33CAF for ; Thu, 16 Jan 2020 19:09:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0D22206E6 for ; Thu, 16 Jan 2020 19:09:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579201761; bh=QQWqVAEri1pk9I3os33sFghXp+ug+wRaDpcOfmO9Jjk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=z2nw0Bo+RInB5H09Io8jUh9xVjNY78ALioItxY6jth5ohmBB3PsMQBd2d/EEfNbsF 5QlFQ6JzhZsqP6DM0bhKPWuPBA4WbIzc0fTdMcMIA1lUfmvqxdSqN0fboz5pNm4teP sQKghRIigQGr6gCemJVUZrYXuHkNIpZfXVeaK680= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387913AbgAPRAt (ORCPT ); Thu, 16 Jan 2020 12:00:49 -0500 Received: from mail.kernel.org ([198.145.29.99]:50948 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387857AbgAPRAs (ORCPT ); Thu, 16 Jan 2020 12:00:48 -0500 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 444312073A; Thu, 16 Jan 2020 17:00:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579194048; bh=QQWqVAEri1pk9I3os33sFghXp+ug+wRaDpcOfmO9Jjk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iMuU4ppsIJeRlv/sGBqnr9zz3qFTFymVqVKYJB5E9SAsNUSn9wluwBAB2IpZwssvx sQmPfQwZpEmDy3k5OcUJVtDTUm+nfkO+c30+2mToKVm4vE1WNVA55ElUkK432MVkTG wkhOuR6Hcec8fxEtGNJaGZkH9CnPxSPZVxF/iDW0= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Colin Ian King , Alexandre Belloni , Sasha Levin , linux-rtc@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 163/671] rtc: 88pm860x: fix unintended sign extension Date: Thu, 16 Jan 2020 11:51:12 -0500 Message-Id: <20200116165940.10720-46-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116165940.10720-1-sashal@kernel.org> References: <20200116165940.10720-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-rtc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org From: Colin Ian King [ Upstream commit dc9e47160626cdb58d5c39a4f43dcfdb27a5c004 ] Shifting a u8 by 24 will cause the value to be promoted to an integer. If the top bit of the u8 is set then the following conversion to an unsigned long will sign extend the value causing the upper 32 bits to be set in the result. Fix this by casting the u8 value to an unsigned long before the shift. Detected by CoverityScan, CID#144925-144928 ("Unintended sign extension") Fixes: 008b30408c40 ("mfd: Add rtc support to 88pm860x") Signed-off-by: Colin Ian King Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin --- drivers/rtc/rtc-88pm860x.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/rtc/rtc-88pm860x.c b/drivers/rtc/rtc-88pm860x.c index fbcf13bbbd8d..73697e4b18a9 100644 --- a/drivers/rtc/rtc-88pm860x.c +++ b/drivers/rtc/rtc-88pm860x.c @@ -115,11 +115,13 @@ static int pm860x_rtc_read_time(struct device *dev, struct rtc_time *tm) pm860x_page_bulk_read(info->i2c, REG0_ADDR, 8, buf); dev_dbg(info->dev, "%x-%x-%x-%x-%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]); - base = (buf[1] << 24) | (buf[3] << 16) | (buf[5] << 8) | buf[7]; + base = ((unsigned long)buf[1] << 24) | (buf[3] << 16) | + (buf[5] << 8) | buf[7]; /* load 32-bit read-only counter */ pm860x_bulk_read(info->i2c, PM8607_RTC_COUNTER1, 4, buf); - data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0]; + data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) | + (buf[1] << 8) | buf[0]; ticks = base + data; dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n", base, data, ticks); @@ -145,7 +147,8 @@ static int pm860x_rtc_set_time(struct device *dev, struct rtc_time *tm) /* load 32-bit read-only counter */ pm860x_bulk_read(info->i2c, PM8607_RTC_COUNTER1, 4, buf); - data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0]; + data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) | + (buf[1] << 8) | buf[0]; base = ticks - data; dev_dbg(info->dev, "set base:0x%lx, RO count:0x%lx, ticks:0x%lx\n", base, data, ticks); @@ -170,10 +173,12 @@ static int pm860x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) pm860x_page_bulk_read(info->i2c, REG0_ADDR, 8, buf); dev_dbg(info->dev, "%x-%x-%x-%x-%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]); - base = (buf[1] << 24) | (buf[3] << 16) | (buf[5] << 8) | buf[7]; + base = ((unsigned long)buf[1] << 24) | (buf[3] << 16) | + (buf[5] << 8) | buf[7]; pm860x_bulk_read(info->i2c, PM8607_RTC_EXPIRE1, 4, buf); - data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0]; + data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) | + (buf[1] << 8) | buf[0]; ticks = base + data; dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n", base, data, ticks); @@ -198,11 +203,13 @@ static int pm860x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) pm860x_page_bulk_read(info->i2c, REG0_ADDR, 8, buf); dev_dbg(info->dev, "%x-%x-%x-%x-%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]); - base = (buf[1] << 24) | (buf[3] << 16) | (buf[5] << 8) | buf[7]; + base = ((unsigned long)buf[1] << 24) | (buf[3] << 16) | + (buf[5] << 8) | buf[7]; /* load 32-bit read-only counter */ pm860x_bulk_read(info->i2c, PM8607_RTC_COUNTER1, 4, buf); - data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0]; + data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) | + (buf[1] << 8) | buf[0]; ticks = base + data; dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n", base, data, ticks); -- 2.20.1