From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753830AbdJMG5T (ORCPT ); Fri, 13 Oct 2017 02:57:19 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:7994 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751024AbdJMG5S (ORCPT ); Fri, 13 Oct 2017 02:57:18 -0400 To: Tyrel Datwyler , , , CC: , Suoben , "Wulizhen (Pss)" From: "Ouyangzhaowei (Charles)" Subject: [RESEND PATCH] scsi: shost->async_scan should be protected by mutex_lock Message-ID: Date: Fri, 13 Oct 2017 14:55:18 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.29.144] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020204.59E063C3.00CA,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: de04c6e945dd384817aea521d2cd6f4c Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org shost->async_scan should be protected by mutex_lock, otherwise the check of "called twice" won't work. Signed-off-by: Ouyang Zhaowei --- drivers/scsi/scsi_scan.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index fd88dab..20d539b 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -1722,9 +1722,10 @@ static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) if (strncmp(scsi_scan_type, "sync", 4) == 0) return NULL; + mutex_lock(&shost->scan_mutex); if (shost->async_scan) { shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__); - return NULL; + goto unlock; } data = kmalloc(sizeof(*data), GFP_KERNEL); @@ -1735,7 +1736,6 @@ static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) goto err; init_completion(&data->prev_finished); - mutex_lock(&shost->scan_mutex); spin_lock_irqsave(shost->host_lock, flags); shost->async_scan = 1; spin_unlock_irqrestore(shost->host_lock, flags); @@ -1751,6 +1751,8 @@ static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) err: kfree(data); + unlock: + mutex_unlock(&shost->scan_mutex); return NULL; }