From patchwork Tue Jan 7 15:40:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eddie James X-Patchwork-Id: 11321099 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BC512930 for ; Tue, 7 Jan 2020 15:41:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A41E52087F for ; Tue, 7 Jan 2020 15:41:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728236AbgAGPlR (ORCPT ); Tue, 7 Jan 2020 10:41:17 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:21248 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727559AbgAGPlR (ORCPT ); Tue, 7 Jan 2020 10:41:17 -0500 Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 007Fcsdd111382; Tue, 7 Jan 2020 10:40:49 -0500 Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0a-001b2d01.pphosted.com with ESMTP id 2xb8p0e0cb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 07 Jan 2020 10:40:49 -0500 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 007FcMw0019021; Tue, 7 Jan 2020 15:40:48 GMT Received: from b03cxnp07028.gho.boulder.ibm.com (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15]) by ppma03dal.us.ibm.com with ESMTP id 2xajb7bdku-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 07 Jan 2020 15:40:48 +0000 Received: from b03ledav003.gho.boulder.ibm.com (b03ledav003.gho.boulder.ibm.com [9.17.130.234]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 007FelIi7340376 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 7 Jan 2020 15:40:47 GMT Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3C0906A057; Tue, 7 Jan 2020 15:40:47 +0000 (GMT) Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CADF46A051; Tue, 7 Jan 2020 15:40:46 +0000 (GMT) Received: from talon7.ibm.com (unknown [9.41.103.158]) by b03ledav003.gho.boulder.ibm.com (Postfix) with ESMTP; Tue, 7 Jan 2020 15:40:46 +0000 (GMT) From: Eddie James To: linux-hwmon@vger.kernel.org Cc: linux-kernel@vger.kernel.org, jdelvare@suse.com, linux@roeck-us.net, dan.carpenter@oracle.com, Eddie James Subject: [PATCH] hwmon: (pmbus/ibm-cffps) Prevent writing on_off_config with bad data Date: Tue, 7 Jan 2020 09:40:40 -0600 Message-Id: <1578411640-16929-1-git-send-email-eajames@linux.ibm.com> X-Mailer: git-send-email 1.8.3.1 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-01-07_05:2020-01-07,2020-01-07 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 impostorscore=0 mlxscore=0 clxscore=1015 phishscore=0 spamscore=0 priorityscore=1501 suspectscore=1 bulkscore=0 adultscore=0 mlxlogscore=999 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-2001070130 Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org If the user write parameters resulted in no bytes being written to the temporary buffer, then ON_OFF_CONFIG will be written with uninitialized data. Prevent this by bailing out in this case. Signed-off-by: Eddie James --- drivers/hwmon/pmbus/ibm-cffps.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hwmon/pmbus/ibm-cffps.c b/drivers/hwmon/pmbus/ibm-cffps.c index 1c91ee1f9926..3795fe55b84f 100644 --- a/drivers/hwmon/pmbus/ibm-cffps.c +++ b/drivers/hwmon/pmbus/ibm-cffps.c @@ -250,7 +250,7 @@ static ssize_t ibm_cffps_debugfs_write(struct file *file, pmbus_set_page(psu->client, 0); rc = simple_write_to_buffer(&data, 1, ppos, buf, count); - if (rc < 0) + if (rc <= 0) return rc; rc = i2c_smbus_write_byte_data(psu->client,