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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED,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 37F10C43387 for ; Fri, 21 Dec 2018 06:13:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F31A0217D9 for ; Fri, 21 Dec 2018 06:13:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=umn.edu header.i=@umn.edu header.b="Kh8DXy/e" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727920AbeLUGN2 (ORCPT ); Fri, 21 Dec 2018 01:13:28 -0500 Received: from mta-p5.oit.umn.edu ([134.84.196.205]:45238 "EHLO mta-p5.oit.umn.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726023AbeLUGN2 (ORCPT ); Fri, 21 Dec 2018 01:13:28 -0500 Received: from localhost (unknown [127.0.0.1]) by mta-p5.oit.umn.edu (Postfix) with ESMTP id A1DF5CEE for ; Fri, 21 Dec 2018 06:13:26 +0000 (UTC) X-Virus-Scanned: amavisd-new at umn.edu Received: from mta-p5.oit.umn.edu ([127.0.0.1]) by localhost (mta-p5.oit.umn.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 6t9Fn9iJFma3 for ; Fri, 21 Dec 2018 00:13:26 -0600 (CST) Received: from mail-io1-f72.google.com (mail-io1-f72.google.com [209.85.166.72]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mta-p5.oit.umn.edu (Postfix) with ESMTPS id 771A3181 for ; Fri, 21 Dec 2018 00:13:26 -0600 (CST) Received: by mail-io1-f72.google.com with SMTP id h7so3492585iof.19 for ; Thu, 20 Dec 2018 22:13:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=umn.edu; s=google; h=from:to:cc:subject:date:message-id; bh=u88FTJY/1v8GAJsUCbqLzQrxjdlKlV6z9U/6eA7D1cQ=; b=Kh8DXy/eZPmI3pI+0rdGUsBcC7F2egsqteyxGqmf+Gz8lVMGUKNKDD2CRwfIuR/qFO yO/Io+o6W1So3zc3bf2DD48enqJGD1gOnDp0vXYfbJqd3g5Gb3/XQMjf4KC7ZV2/0Ykk 6QufFTaGD0cs126KwPQD5i/l7uu+f2poA0pL1oFwFJuJPZ3JNO1vSr9efdUrqT9cOeR+ TASZ3GUwjl3xFJOx8PxhFEmCq081kVAnfnPkqe+tGEFYQHo655a96pt9Vn043v92GDaS HKIOPV2B9wiVozSvee3lB8BNwQhoaEDSCYbpUoRBYjlK8eNW2q5HIwX93YI17WIlS7wt cDDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=u88FTJY/1v8GAJsUCbqLzQrxjdlKlV6z9U/6eA7D1cQ=; b=O+0T5PqjnGkhvZZ81UpnHUaKSxxK8dWi+Ed1yHEmKg8OUqEOvnqKcek7xd9+yrXLtz qQCJXVxZDY1PimwweK0CDYauqXr5bMCCidjAwuO1kjooajiW7UI4CCWIgfqD9QkvmlEI zbMaAy1stOavImRPZZSa6jRVRa3UHLZrbROXb7lXxxp4iNjBcfPy8XOJgL8H0K05CW3c UVmI6iYE+iI8/AequgNgTaQqFWoumtyzW7YMwOSAWyZUP1doJWsOURuX3bNhHh0FTPwc 1r7rVOKilg5EyOnBGLtlQT/LCCY3DpCXcTofEHu3ntcUOXzMKKQ+EtCdIZv82KYRC0ZA augQ== X-Gm-Message-State: AJcUukfG709Cyx9U7FTujGoTaAem3bsy8YbmW9ikWyWmfEewZtzsXqnA LXHuMZ2oczNhnj7391Uq9mRegv7Bs0jC2Dovv6zQfOTtCLaiB4YL5QjPo2LuWt27sveKzxNsMvT ZTW4mG/oLFmVxRwv4a7erlW3QbaDa X-Received: by 2002:a5d:94c8:: with SMTP id y8mr274599ior.285.1545372806066; Thu, 20 Dec 2018 22:13:26 -0800 (PST) X-Google-Smtp-Source: ALg8bN6T5h6lhFjSvNzhWY4zSHbX8rUTiOekEMraQIKztngTx73T31KyEf54n7HVXdbhgUVhK8I7Zw== X-Received: by 2002:a5d:94c8:: with SMTP id y8mr274591ior.285.1545372805722; Thu, 20 Dec 2018 22:13:25 -0800 (PST) Received: from localhost.localdomain (host-173-230-104-23.mnmigsc.mn.minneapolis.us.clients.pavlovmedia.net. [173.230.104.23]) by smtp.gmail.com with ESMTPSA id a16sm10381370ioh.48.2018.12.20.22.13.24 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 20 Dec 2018 22:13:24 -0800 (PST) From: Kangjie Lu To: kjlu@umn.edu Cc: pakki001@umn.edu, Jean Delvare , Guenter Roeck , linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] hwmon: lm80: fix a missing check of return value Date: Fri, 21 Dec 2018 00:13:03 -0600 Message-Id: <20181221061304.59684-1-kjlu@umn.edu> X-Mailer: git-send-email 2.17.2 (Apple Git-113) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If lm80_read_value() fails, it returns a negative number instead of the correct read data. Therefore, we should avoid using the data if it fails. The fix checks if lm80_read_value() fails, and if so, returns with the error number. Signed-off-by: Kangjie Lu --- drivers/hwmon/lm80.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/hwmon/lm80.c b/drivers/hwmon/lm80.c index 08e3945a6fbf..fca6363cd77f 100644 --- a/drivers/hwmon/lm80.c +++ b/drivers/hwmon/lm80.c @@ -360,9 +360,11 @@ static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr, struct i2c_client *client = data->client; unsigned long min, val; u8 reg; - int err = kstrtoul(buf, 10, &val); - if (err < 0) - return err; + int ret; + + ret = kstrtoul(buf, 10, &val); + if (ret < 0) + return ret; /* Save fan_min */ mutex_lock(&data->update_lock); @@ -390,8 +392,11 @@ static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr, return -EINVAL; } - reg = (lm80_read_value(client, LM80_REG_FANDIV) & - ~(3 << (2 * (nr + 1)))) | (data->fan_div[nr] << (2 * (nr + 1))); + ret = lm80_read_value(client, LM80_REG_FANDIV); + if (ret < 0) + return ret; + reg = (ret & ~(3 << (2 * (nr + 1)))) + | (data->fan_div[nr] << (2 * (nr + 1))); lm80_write_value(client, LM80_REG_FANDIV, reg); /* Restore fan_min */ -- 2.17.2 (Apple Git-113)