From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751538AbaBNCvU (ORCPT ); Thu, 13 Feb 2014 21:51:20 -0500 Received: from mail.active-venture.com ([67.228.131.205]:62895 "EHLO mail.active-venture.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751089AbaBNCvT (ORCPT ); Thu, 13 Feb 2014 21:51:19 -0500 X-Originating-IP: 108.223.40.66 Message-ID: <52FD84A6.9000400@roeck-us.net> Date: Thu, 13 Feb 2014 18:51:18 -0800 From: Guenter Roeck User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: Doug Anderson , Jean Delvare CC: lm-sensors@lm-sensors.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] hwmon: (ntc_thermistor): Avoid overflow References: <1392331174-12271-1-git-send-email-dianders@chromium.org> In-Reply-To: <1392331174-12271-1-git-send-email-dianders@chromium.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/13/2014 02:39 PM, Doug Anderson wrote: > The ntc thermistor code was doing math whose temporary result might > have overflowed 32-bits. We need some casts in there to make it safe. > > In one example I found: > - pullup_uV: 1800000 > - result of iio_read_channel_raw: 3226 > - 1800000 * 3226 => 0x15a1cbc80 > > Signed-off-by: Doug Anderson Nice catch. Applied. Thanks, Guenter