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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 6C168C48BDE for ; Sun, 7 Jul 2019 19:45:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4CE0E20830 for ; Sun, 7 Jul 2019 19:45:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728544AbfGGTpG (ORCPT ); Sun, 7 Jul 2019 15:45:06 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:57176 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727429AbfGGTiG (ORCPT ); Sun, 7 Jul 2019 15:38:06 -0400 Received: from 94.197.121.43.threembb.co.uk ([94.197.121.43] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hkCz4-0006gY-TI; Sun, 07 Jul 2019 20:38:03 +0100 Received: from ben by deadeye with local (Exim 4.92) (envelope-from ) id 1hkCz3-0005aN-I0; Sun, 07 Jul 2019 20:38:01 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Alexandre Belloni" , "Colin Ian King" Date: Sun, 07 Jul 2019 17:54:17 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 051/129] rtc: 88pm860x: fix unintended sign extension In-Reply-To: X-SA-Exim-Connect-IP: 94.197.121.43 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.70-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Colin Ian King commit dc9e47160626cdb58d5c39a4f43dcfdb27a5c004 upstream. 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: Ben Hutchings --- drivers/rtc/rtc-88pm860x.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) --- a/drivers/rtc/rtc-88pm860x.c +++ b/drivers/rtc/rtc-88pm860x.c @@ -115,11 +115,13 @@ static int pm860x_rtc_read_time(struct d 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 de /* 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 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 d 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);