From patchwork Thu Oct 11 04:12:16 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 10635759 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DAF2A17E1 for ; Thu, 11 Oct 2018 04:13:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C171A21BED for ; Thu, 11 Oct 2018 04:13:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B59D825223; Thu, 11 Oct 2018 04:13:15 +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=-5.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from aserp2120.oracle.com (aserp2120.oracle.com [141.146.126.78]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 3C5C121BED for ; Thu, 11 Oct 2018 04:13:15 +0000 (UTC) Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w9B4971U052718; Thu, 11 Oct 2018 04:12:52 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : date : message-id : mime-version : cc : subject : list-id : list-unsubscribe : list-archive : list-post : list-help : list-subscribe : content-type : content-transfer-encoding : sender; s=corp-2018-07-02; bh=sc/xuv6De9YN2//eUmjVUGSlaVYh/xanni2IlA2yc4k=; b=Fz4Cydf3sfN9ge7eKguRxU8wo9wJm5FLHqxzG7WAV3cq3hLT/Bec7Jo/9/+TaybM7ZBD Q8a+tb3H0t/kB1i5vs1u2DyMDBNNVZA0A3zs9xhkzAmclR20Gcgw3YAuu+AFNJ0uCgnc 25IhhHWVtaDYaesYk/W/wfNayxADfA/PiIU6AfUPvLlsjlfsB0cgvRV7QUPv9BPI3C0p LP+c0VoNqfnCxz+Zw43ItUOPrlJ7gl5p1gaXqSSvZZk+XbHPzv87SLNQRZLzZJkixJSS lftYWKGMe9OQTltoRcmAR3uLDuCBFOBr8fHQvFUZz3gegreZrwauGcELO+TKTa5QqZUz 9g== Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by aserp2120.oracle.com with ESMTP id 2mxn0q9dt5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 11 Oct 2018 04:12:52 +0000 Received: from oss.oracle.com (oss-old-reserved.oracle.com [137.254.22.2]) by userv0022.oracle.com (8.14.4/8.14.4) with ESMTP id w9B4ClIg017227 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 11 Oct 2018 04:12:48 GMT Received: from localhost ([127.0.0.1] helo=lb-oss.oracle.com) by oss.oracle.com with esmtp (Exim 4.63) (envelope-from ) id 1gASL9-0006dU-Pq; Wed, 10 Oct 2018 21:12:47 -0700 Received: from aserv0021.oracle.com ([141.146.126.233]) by oss.oracle.com with esmtp (Exim 4.63) (envelope-from ) id 1gASKi-0006bc-Ox for ocfs2-devel@oss.oracle.com; Wed, 10 Oct 2018 21:12:20 -0700 Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserv0021.oracle.com (8.14.4/8.14.4) with ESMTP id w9B4CJF0010021 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 11 Oct 2018 04:12:20 GMT Received: from abhmp0009.oracle.com (abhmp0009.oracle.com [141.146.116.15]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id w9B4CIpb029404; Thu, 11 Oct 2018 04:12:18 GMT Received: from localhost (/10.159.132.249) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 11 Oct 2018 04:12:18 +0000 From: "Darrick J. Wong" To: david@fromorbit.com, darrick.wong@oracle.com Date: Wed, 10 Oct 2018 21:12:16 -0700 Message-ID: <153923113649.5546.9840926895953408273.stgit@magnolia> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Cc: sandeen@redhat.com, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, ocfs2-devel@oss.oracle.com, linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org Subject: [Ocfs2-devel] [PATCH v3 00/25] fs: fixes for serious clone/dedupe problems X-BeenThere: ocfs2-devel@oss.oracle.com X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: ocfs2-devel-bounces@oss.oracle.com Errors-To: ocfs2-devel-bounces@oss.oracle.com X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9042 signatures=668706 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=8.0.1-1807170000 definitions=main-1810110039 X-Virus-Scanned: ClamAV using ClamSMTP Hi all, Dave, Eric, and I have been chasing a stale data exposure bug in the XFS reflink implementation, and tracked it down to reflink forgetting to do some of the file-extending activities that must happen for regular writes. We then started auditing the clone, dedupe, and copyfile code and realized that from a file contents perspective, clonerange isn't any different from a regular file write. Unfortunately, we also noticed that *unlike* a regular write, clonerange skips a ton of overflow checks, such as validating the ranges against s_maxbytes, MAX_NON_LFS, and RLIMIT_FSIZE. We also observed that cloning into a file did not strip security privileges (suid, capabilities) like a regular write would. I also noticed that xfs and ocfs2 need to dump the page cache before remapping blocks, not after. In fixing the range checking problems I also realized that both dedupe and copyfile tell userspace how much of the requested operation was acted upon. Since the range validation can shorten a clone request (or we can ENOSPC midway through), we might as well plumb the short operation reporting back through the VFS indirection code to userspace. So, here's the whole giant pile of patches[1] that fix all the problems. This branch is against 4.19-rc7 with Dave Chinner's XFS for-next branch. The patch "generic: test reflink side effects" recently sent to fstests exercises the fixes in this series. Tests are in [2]. --D [1] https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux.git/log/?h=djwong-devel [2] https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfstests-dev.git/log/?h=djwong-devel