From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61E7FC47253 for ; Thu, 30 Apr 2020 15:16:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F5D120661 for ; Thu, 30 Apr 2020 15:16:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="WwINN9yG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726546AbgD3PQs (ORCPT ); Thu, 30 Apr 2020 11:16:48 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:54520 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726285AbgD3PQs (ORCPT ); Thu, 30 Apr 2020 11:16:48 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 03UFD55d169844; Thu, 30 Apr 2020 15:16:37 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2020-01-29; bh=Tm0TEordpY3zCjdu1wJVpqKvrP0I5ede7+XgdfzJldU=; b=WwINN9yG3SwxNx++5RYPsoCaqb5qwBwZzH66lR+Idu0SaSjT/mqPwTECgB+l1w/ItS5d 2Esj0qCQYN/rc6z85unrWZ0JZCYDOsyjI9ttl7RqZZXsp70mMOHOk5nc4HjPgrJysER8 vesYG/LoGDIVjSIOLuTOBTuSSvo6CjCrAnAN+Rlq4hsec63l4WIQQhxuE7nmOHJ0wWxq CVS1al0HYXXogITplQFDOBfDhtdUKhDxrpiwG7HmbUFEaFwNOzAPqMXx7/afH55k6wuy ssmBBoC0PQwDMbmC1Hg+y4brZMtNy/mDNk4DNTP3kiL5A4eWFBEdczpZ7VC01iVgqJdH HA== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by aserp2120.oracle.com with ESMTP id 30nucgc2eu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 30 Apr 2020 15:16:36 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 03UFCRUw041962; Thu, 30 Apr 2020 15:16:36 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userp3020.oracle.com with ESMTP id 30qtg167rs-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 30 Apr 2020 15:16:36 +0000 Received: from abhmp0020.oracle.com (abhmp0020.oracle.com [141.146.116.26]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 03UFGXBM015036; Thu, 30 Apr 2020 15:16:33 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 30 Apr 2020 08:16:33 -0700 Date: Thu, 30 Apr 2020 08:16:31 -0700 From: "Darrick J. Wong" To: Ritesh Harjani Cc: linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, Alexander Viro , Christoph Hellwig , Jan Kara , tytso@mit.edu, "Aneesh Kumar K . V" , linux-ext4@vger.kernel.org Subject: Re: [PATCHv3 1/1] fibmap: Warn and return an error in case of block > INT_MAX Message-ID: <20200430151631.GK6733@magnolia> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9607 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 adultscore=0 mlxlogscore=999 phishscore=0 malwarescore=0 spamscore=0 bulkscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004300123 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9607 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 clxscore=1015 priorityscore=1501 mlxlogscore=999 impostorscore=0 suspectscore=0 malwarescore=0 lowpriorityscore=0 mlxscore=0 spamscore=0 adultscore=0 phishscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004300123 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Thu, Apr 30, 2020 at 10:25:18AM +0530, Ritesh Harjani wrote: > We better warn the fibmap user and not return a truncated and therefore > an incorrect block map address if the bmap() returned block address > is greater than INT_MAX (since user supplied integer pointer). > > It's better to pr_warn() all user of ioctl_fibmap() and return a proper > error code rather than silently letting a FS corruption happen if the > user tries to fiddle around with the returned block map address. > > We fix this by returning an error code of -ERANGE and returning 0 as the > block mapping address in case if it is > INT_MAX. > > Now iomap_bmap() could be called from either of these two paths. > Either when a user is calling an ioctl_fibmap() interface to get > the block mapping address or by some filesystem via use of bmap() > internal kernel API. > bmap() kernel API is well equipped with handling of u64 addresses. > > WARN condition in iomap_bmap_actor() was mainly added to warn all > the fibmap users. But now that we have directly added this warning > for all fibmap users and also made sure to return 0 as block map address > in case if addr > INT_MAX. > So we can now remove this logic from iomap_bmap_actor(). > > Signed-off-by: Ritesh Harjani Looks good to me, Reviewed-by: Darrick J. Wong --D > --- > v2 -> v3: > 1. Added file path info using (%pD4) > 2. Dropped Reviewed-by tags for reviewing this final version. > > fs/ioctl.c | 8 ++++++++ > fs/iomap/fiemap.c | 5 +---- > 2 files changed, 9 insertions(+), 4 deletions(-) > > diff --git a/fs/ioctl.c b/fs/ioctl.c > index f1d93263186c..6b8629fbe0fd 100644 > --- a/fs/ioctl.c > +++ b/fs/ioctl.c > @@ -55,6 +55,7 @@ EXPORT_SYMBOL(vfs_ioctl); > static int ioctl_fibmap(struct file *filp, int __user *p) > { > struct inode *inode = file_inode(filp); > + struct super_block *sb = inode->i_sb; > int error, ur_block; > sector_t block; > > @@ -71,6 +72,13 @@ static int ioctl_fibmap(struct file *filp, int __user *p) > block = ur_block; > error = bmap(inode, &block); > > + if (block > INT_MAX) { > + error = -ERANGE; > + pr_warn_ratelimited("[%s/%d] FS: %s File: %pD4 would truncate fibmap result\n", > + current->comm, task_pid_nr(current), > + sb->s_id, filp); > + } > + > if (error) > ur_block = 0; > else > diff --git a/fs/iomap/fiemap.c b/fs/iomap/fiemap.c > index bccf305ea9ce..d55e8f491a5e 100644 > --- a/fs/iomap/fiemap.c > +++ b/fs/iomap/fiemap.c > @@ -117,10 +117,7 @@ iomap_bmap_actor(struct inode *inode, loff_t pos, loff_t length, > > if (iomap->type == IOMAP_MAPPED) { > addr = (pos - iomap->offset + iomap->addr) >> inode->i_blkbits; > - if (addr > INT_MAX) > - WARN(1, "would truncate bmap result\n"); > - else > - *bno = addr; > + *bno = addr; > } > return 0; > } > -- > 2.21.0 >