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=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 7E9E9C33CB3 for ; Thu, 16 Jan 2020 18:33:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 58643206D7 for ; Thu, 16 Jan 2020 18:33:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579199624; bh=/7Jt2WKsId0mWZYHVt27b4RtZaiSQACvRaQAiKA8aTM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jq0eRnn0Q/dpab7jbQ9ycC8xxEmBuHuK3KYbm8395o+a6oyYzuBNgQbspWf/0C/m9 kUwsr2JWTygxglJ+ee7nBfz4S7Orv29ROXPb3r7KZyLbGEnyLdkljku6nO8HEDitKE pHVRPKDIRMdTd0GtmcITyUOyNLYio5BEEnRppy+k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391810AbgAPRYt (ORCPT ); Thu, 16 Jan 2020 12:24:49 -0500 Received: from mail.kernel.org ([198.145.29.99]:59648 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2403767AbgAPRYm (ORCPT ); Thu, 16 Jan 2020 12:24:42 -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 07453246AE; Thu, 16 Jan 2020 17:24:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579195481; bh=/7Jt2WKsId0mWZYHVt27b4RtZaiSQACvRaQAiKA8aTM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qbbMc+dSe2wbkXq/ruUN/wX4Vquaa6g7VorsRkwXkBt6Y/vPmvPSrTgrTw6e759AK c1kUMQ426ymQmbEnhnGYiRpaEreFUI/7pEa59tea5lB45OvRw466nTBqZMUjlomR8U i9kKQkDuV0bi5PREO4+Dy/exoTluFsfoYZjT24Aw= 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 4.14 086/371] rtc: 88pm860x: fix unintended sign extension Date: Thu, 16 Jan 2020 12:19:18 -0500 Message-Id: <20200116172403.18149-29-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116172403.18149-1-sashal@kernel.org> References: <20200116172403.18149-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 166faae3a59c..7d3e5168fcef 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