From patchwork Fri Apr 28 12:52:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 41059 Received: from mail.tu-berlin.de ([130.149.7.33]) by www.linuxtv.org with esmtp (Exim 4.84_2) (envelope-from ) id 1d45OP-0007T6-2Q; Fri, 28 Apr 2017 12:53:01 +0000 X-tubIT-Incoming-IP: 209.132.180.67 Received: from vger.kernel.org ([209.132.180.67]) by mail.tu-berlin.de (exim-4.84_2/mailfrontend-8) with esmtp id 1d45OM-0006zZ-mC; Fri, 28 Apr 2017 14:53:00 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1425867AbdD1Mw4 (ORCPT + 1 other); Fri, 28 Apr 2017 08:52:56 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:21049 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1425861AbdD1Mww (ORCPT ); Fri, 28 Apr 2017 08:52:52 -0400 Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by userp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id v3SCqYsS020114 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 28 Apr 2017 12:52:35 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserv0021.oracle.com (8.13.8/8.14.4) with ESMTP id v3SCqX8L010750 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 28 Apr 2017 12:52:34 GMT Received: from abhmp0003.oracle.com (abhmp0003.oracle.com [141.146.116.9]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id v3SCqKNX007120; Fri, 28 Apr 2017 12:52:21 GMT Received: from mwanda (/197.254.35.146) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 28 Apr 2017 05:52:19 -0700 Date: Fri, 28 Apr 2017 15:52:07 +0300 From: Dan Carpenter To: Mauro Carvalho Chehab Cc: Patrick Boettcher , Hans Verkuil , Sean Young , Wolfram Sang , Kees Cook , Johan Hovold , linux-media@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH 1/2] [media] dib0700: fix locking in dib0700_i2c_xfer_new() Message-ID: <20170428125207.skjv7ak2nmwltxik@mwanda> MIME-Version: 1.0 Content-Disposition: inline X-Mailer: git-send-email haha only kidding User-Agent: NeoMutt/20170113 (1.7.2) X-Source-IP: aserv0021.oracle.com [141.146.126.233] Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-PMX-Version: 6.0.0.2142326, Antispam-Engine: 2.7.2.2107409, Antispam-Data: 2017.4.28.124516 X-PMX-Spam: Gauge=IIIIIIIII, Probability=9%, Report=' MULTIPLE_RCPTS 0.1, HTML_00_01 0.05, HTML_00_10 0.05, MSGID_ADDED_BY_MTA 0.05, BODYTEXTP_SIZE_3000_LESS 0, BODY_SIZE_1800_1899 0, BODY_SIZE_2000_LESS 0, BODY_SIZE_5000_LESS 0, BODY_SIZE_7000_LESS 0, INVALID_MSGID_NO_FQDN 0, LEGITIMATE_SIGNS 0, MULTIPLE_REAL_RCPTS 0, NO_URI_HTTPS 0, __ANY_URI 0, __CC_NAME 0, __CC_NAME_DIFF_FROM_ACC 0, __CC_REAL_NAMES 0, __CD 0, __CT 0, __CT_TEXT_PLAIN 0, __DATE_TZ_RU 0, __HAS_CC_HDR 0, __HAS_FROM 0, __HAS_LIST_ID 0, __HAS_MSGID 0, __HAS_X_MAILER 0, __HAS_X_MAILING_LIST 0, __MIME_TEXT_ONLY 0, __MIME_TEXT_P 0, __MIME_TEXT_P1 0, __MIME_VERSION 0, __MULTIPLE_RCPTS_CC_X2 0, __NO_HTML_TAG_RAW 0, __SANE_MSGID 0, __TO_MALFORMED_2 0, __TO_NAME 0, __TO_NAME_DIFF_FROM_ACC 0, __TO_REAL_NAMES 0, __URI_NO_WWW 0, __URI_NS , __USER_AGENT 0' This patch mostly adds unlocks to error paths. But one additional small change is that I made the first "break;" a "goto unlock;" which means that now we return failure instead of success on that path. Signed-off-by: Dan Carpenter diff --git a/drivers/media/usb/dvb-usb/dib0700_core.c b/drivers/media/usb/dvb-usb/dib0700_core.c index 08acdd32e412..4dea79718827 100644 --- a/drivers/media/usb/dvb-usb/dib0700_core.c +++ b/drivers/media/usb/dvb-usb/dib0700_core.c @@ -215,13 +215,14 @@ static int dib0700_i2c_xfer_new(struct i2c_adapter *adap, struct i2c_msg *msg, USB_CTRL_GET_TIMEOUT); if (result < 0) { deb_info("i2c read error (status = %d)\n", result); - break; + goto unlock; } if (msg[i].len > sizeof(st->buf)) { deb_info("buffer too small to fit %d bytes\n", msg[i].len); - return -EIO; + result = -EIO; + goto unlock; } memcpy(msg[i].buf, st->buf, msg[i].len); @@ -233,8 +234,8 @@ static int dib0700_i2c_xfer_new(struct i2c_adapter *adap, struct i2c_msg *msg, /* Write request */ if (mutex_lock_interruptible(&d->usb_mutex) < 0) { err("could not acquire lock"); - mutex_unlock(&d->i2c_mutex); - return -EINTR; + result = -EINTR; + goto unlock; } st->buf[0] = REQUEST_NEW_I2C_WRITE; st->buf[1] = msg[i].addr << 1; @@ -247,7 +248,9 @@ static int dib0700_i2c_xfer_new(struct i2c_adapter *adap, struct i2c_msg *msg, if (msg[i].len > sizeof(st->buf) - 4) { deb_info("i2c message to big: %d\n", msg[i].len); - return -EIO; + mutex_unlock(&d->usb_mutex); + result = -EIO; + goto unlock; } /* The Actual i2c payload */ @@ -269,8 +272,11 @@ static int dib0700_i2c_xfer_new(struct i2c_adapter *adap, struct i2c_msg *msg, } } } + result = i; + +unlock: mutex_unlock(&d->i2c_mutex); - return i; + return result; } /*