From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932214Ab1CUXQh (ORCPT ); Mon, 21 Mar 2011 19:16:37 -0400 Received: from kroah.org ([198.145.64.141]:49698 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932149Ab1CUXQ1 (ORCPT ); Mon, 21 Mar 2011 19:16:27 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Mon Mar 21 16:07:18 2011 Message-Id: <20110321230718.166337358@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Mon, 21 Mar 2011 16:07:26 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Vivien Didelot , Jean Delvare , Jonathan Cameron Subject: [87/87] hwmon: (sht15) Fix integer overflow in humidity calculation In-Reply-To: <20110321230732.GA26510@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.37-stable review patch. If anyone has any objections, please let us know. ------------------ From: Vivien Didelot commit ccd32e735de7a941906e093f8dca924bb05c5794 upstream. An integer overflow occurs in the calculation of RHlinear when the relative humidity is greater than around 30%. The consequence is a subtle (but noticeable) error in the resulting humidity measurement. Signed-off-by: Vivien Didelot Signed-off-by: Jean Delvare Cc: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- drivers/hwmon/sht15.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/hwmon/sht15.c +++ b/drivers/hwmon/sht15.c @@ -333,11 +333,11 @@ static inline int sht15_calc_humid(struc const int c1 = -4; const int c2 = 40500; /* x 10 ^ -6 */ - const int c3 = -2800; /* x10 ^ -9 */ + const int c3 = -28; /* x 10 ^ -7 */ RHlinear = c1*1000 + c2 * data->val_humid/1000 - + (data->val_humid * data->val_humid * c3)/1000000; + + (data->val_humid * data->val_humid * c3) / 10000; return (temp - 25000) * (10000 + 80 * data->val_humid) / 1000000 + RHlinear; }