From patchwork Wed Jun 28 17:14:21 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Matthew R. Ochs" X-Patchwork-Id: 9814911 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5865A60365 for ; Wed, 28 Jun 2017 17:14:36 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3E1201FF35 for ; Wed, 28 Jun 2017 17:14:36 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 324E826247; Wed, 28 Jun 2017 17:14:36 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D06221FF35 for ; Wed, 28 Jun 2017 17:14:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751541AbdF1ROf (ORCPT ); Wed, 28 Jun 2017 13:14:35 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:45078 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751516AbdF1ROe (ORCPT ); Wed, 28 Jun 2017 13:14:34 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v5SHDmcw093052 for ; Wed, 28 Jun 2017 13:14:33 -0400 Received: from e18.ny.us.ibm.com (e18.ny.us.ibm.com [129.33.205.208]) by mx0b-001b2d01.pphosted.com with ESMTP id 2bcf4ammqy-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 28 Jun 2017 13:14:33 -0400 Received: from localhost by e18.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 28 Jun 2017 13:14:33 -0400 Received: from b01cxnp22035.gho.pok.ibm.com (9.57.198.25) by e18.ny.us.ibm.com (146.89.104.205) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Wed, 28 Jun 2017 13:14:31 -0400 Received: from b01ledav004.gho.pok.ibm.com (b01ledav004.gho.pok.ibm.com [9.57.199.109]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v5SHEUh956426516; Wed, 28 Jun 2017 17:14:30 GMT Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9ABF911204B; Wed, 28 Jun 2017 13:14:32 -0400 (EDT) Received: from p8tul1-build.aus.stglabs.ibm.com (unknown [9.3.141.206]) by b01ledav004.gho.pok.ibm.com (Postfix) with ESMTP id AB16B112034; Wed, 28 Jun 2017 13:14:31 -0400 (EDT) From: "Matthew R. Ochs" To: linux-scsi@vger.kernel.org, James Bottomley , "Martin K. Petersen" , Uma Krishnan , "Manoj N. Kumar" , Hannes Reinecke Cc: Frederic Barrat , Andrew Donnellan , Christophe Lombard , linuxppc-dev@lists.ozlabs.org, "Matthew R. Ochs" Subject: [PATCH 1/3] cxlflash: Avoid double free of character device Date: Wed, 28 Jun 2017 12:14:21 -0500 X-Mailer: git-send-email 2.1.0 In-Reply-To: <1498669929-39684-1-git-send-email-mrochs@linux.vnet.ibm.com> References: <1498669929-39684-1-git-send-email-mrochs@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17062817-0044-0000-0000-0000035EC16F X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007291; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000214; SDB=6.00879993; UDB=6.00438643; IPR=6.00660147; BA=6.00005445; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015993; XFM=3.00000015; UTC=2017-06-28 17:14:32 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17062817-0045-0000-0000-0000078CCA9B Message-Id: <1498670061-39766-1-git-send-email-mrochs@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-06-28_11:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1706280275 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The device_unregister() service used when cleaning up the character device is already responsible for the internal state associated with the device upon successful creation. As the cxlflash driver does not obtain a second reference to the character device, the explicit call to put_device() is not required and can lead to an inconsistent sysfs among other issues as the reference is no longer valid after the first put_device() is performed. Remove the unnecessary put_device() to remedy this issue. Fixes: a834a36b57d9 ("scsi: cxlflash: Create character device to provide host management interface") Signed-off-by: Matthew R. Ochs Reviewed-by: Hannes Reinecke --- drivers/scsi/cxlflash/main.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index 7a787b6..455564f 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -923,7 +923,6 @@ static void cxlflash_put_minor(int minor) */ static void cxlflash_release_chrdev(struct cxlflash_cfg *cfg) { - put_device(cfg->chardev); device_unregister(cfg->chardev); cfg->chardev = NULL; cdev_del(&cfg->cdev);