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Wed, 04 Sep 2019 14:57:14 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x84EqgYt065225; Wed, 4 Sep 2019 14:57:13 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3030.oracle.com with ESMTP id 2usu51xw9s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 04 Sep 2019 14:57:13 +0000 Received: from abhmp0017.oracle.com (abhmp0017.oracle.com [141.146.116.23]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x84Ev9FT025123; Wed, 4 Sep 2019 14:57:10 GMT Received: from kadam (/41.57.98.10) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 04 Sep 2019 07:57:09 -0700 Date: Wed, 4 Sep 2019 17:57:01 +0300 From: Dan Carpenter To: Anders Larsen Cc: Markus Elfring , kernel-janitors@vger.kernel.org, Al Viro , Deepa Dinamani , Greg Kroah-Hartman , Jeff Layton , Thomas Gleixner , LKML Subject: Re: [PATCH] fs/qnx: Delete unnecessary checks before brelse() Message-ID: <20190904145700.GB3115@kadam> References: <056c8b8e-abaa-8856-4953-118d14048ddc@web.de> <21774224.cEpxz9ejUk@alarsen.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <21774224.cEpxz9ejUk@alarsen.net> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9369 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1909040146 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9369 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1909040146 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 03, 2019 at 07:27:22PM +0200, Anders Larsen wrote: > On Tuesday, 2019-09-03 19:20 Markus Elfring wrote: > > diff --git a/fs/qnx6/inode.c b/fs/qnx6/inode.c > > index 345db56c98fd..083170541add 100644 > > --- a/fs/qnx6/inode.c > > +++ b/fs/qnx6/inode.c > > @@ -472,10 +472,8 @@ static int qnx6_fill_super(struct super_block *s, void *data, int silent) > > out1: > > iput(sbi->inodes); > > out: > > - if (bh1) > > - brelse(bh1); > > - if (bh2) > > - brelse(bh2); > > + brelse(bh1); > > + brelse(bh2); > > outnobh: > > kfree(qs); > > s->s_fs_info = NULL; It looks like the original code is buggy: fs/qnx6/inode.c 409 pr_info("superblock #1 active\n"); 410 } else { 411 /* superblock #2 active */ 412 sbi->sb_buf = bh2; 413 sbi->sb = (struct qnx6_super_block *)bh2->b_data; 414 brelse(bh1); ^^^^^^^^^^ brelse() 415 pr_info("superblock #2 active\n"); 416 } 417 mmi_success: 418 /* sanity check - limit maximum indirect pointer levels */ 419 if (sb1->Inode.levels > QNX6_PTR_MAX_LEVELS) { 420 pr_err("too many inode levels (max %i, sb %i)\n", 421 QNX6_PTR_MAX_LEVELS, sb1->Inode.levels); 422 goto out; ^^^^^^^^ goto 423 } [ snip ] 466 467 out3: 468 dput(s->s_root); 469 s->s_root = NULL; 470 out2: 471 iput(sbi->longfile); 472 out1: 473 iput(sbi->inodes); 474 out: 475 if (bh1) 476 brelse(bh1); ^^^^^^^^^^^ Double brelse(). 477 if (bh2) 478 brelse(bh2); 479 outnobh: 480 kfree(qs); 481 s->s_fs_info = NULL; 482 return ret; 483 } regards, dan carpenter