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=-10.3 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_PASS,UNPARSEABLE_RELAY,USER_AGENT_MUTT autolearn=ham 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 F0953C04EB9 for ; Mon, 3 Dec 2018 19:11:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B7CB320848 for ; Mon, 3 Dec 2018 19:11:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="oE60gd9y" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B7CB320848 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nfs-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726044AbeLCTLj (ORCPT ); Mon, 3 Dec 2018 14:11:39 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:47130 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725987AbeLCTLj (ORCPT ); Mon, 3 Dec 2018 14:11:39 -0500 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id wB3J3d4g033513; Mon, 3 Dec 2018 19:11:33 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-2018-07-02; bh=npRy/f8qZDzX/wpE4CbdsG0mnbzF9zNJXzFByhFdrjY=; b=oE60gd9ye1X74qDSyxICCrhR24aXYP2E7paxTz3MqOyrHWj8y5AS7mKT+8jqQ31I2yL7 MuqL+VyTg9E8funBIHGPgXXsIT+svBi8qQBeRrnBx10HJWluMmGLuL6EbtyjQj/Y50ZT cGxWHAI2Cq6QJyrQQj3lz7rTmO8Iw9TdThMLiIR24mJHMOeEvpV68Db3ivKrMSuh9Q6G RUvSgfgUiFuaKmjb28QqwTz3KqImysakDV2J+ahYXsczT5Vjsub/D3nPqY1+CKeuF8aO araWol8MLKqQ7iw28lWngrZtTFeNPntPmJw+A74pjoNXli1sHEBx1WwZ8cVuRTcwOjZq gA== Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by userp2120.oracle.com with ESMTP id 2p3jxr87dj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 03 Dec 2018 19:11:33 +0000 Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userv0022.oracle.com (8.14.4/8.14.4) with ESMTP id wB3JBXL2001386 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 3 Dec 2018 19:11:33 GMT Received: from abhmp0019.oracle.com (abhmp0019.oracle.com [141.146.116.25]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id wB3JBWH3009224; Mon, 3 Dec 2018 19:11:32 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 03 Dec 2018 11:11:32 -0800 Date: Mon, 3 Dec 2018 11:11:30 -0800 From: "Darrick J. Wong" To: Amir Goldstein Cc: Dave Chinner , linux-fsdevel , linux-xfs , Olga Kornievskaia , Linux NFS Mailing List , overlayfs , ceph-devel@vger.kernel.org, linux-cifs@vger.kernel.org Subject: Re: [PATCH 08/11] vfs: push EXDEV check down into ->remap_file_range Message-ID: <20181203191130.GD24487@magnolia> References: <20181203083416.28978-1-david@fromorbit.com> <20181203083416.28978-9-david@fromorbit.com> 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=5900 definitions=9096 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=815 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1812030176 Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Mon, Dec 03, 2018 at 01:04:07PM +0200, Amir Goldstein wrote: > On Mon, Dec 3, 2018 at 10:34 AM Dave Chinner wrote: > > > > From: Dave Chinner > > > > before we can enable cross-device copies into copy_file_range(), > > we have to ensure that ->remap_file_range() implemenations will > > correctly reject attempts to do cross filesystem clones. Currently > > But you only fixed remap_file_range() implemenations of xfs and ocfs2... > > > these checks are done above calls to ->remap_file_range(), but > > we need to drive them inwards so that we get EXDEV protection for all > > callers of ->remap_file_range(). > > > > Signed-off-by: Dave Chinner > > --- > > fs/read_write.c | 21 +++++++++++++-------- > > 1 file changed, 13 insertions(+), 8 deletions(-) > > > > diff --git a/fs/read_write.c b/fs/read_write.c > > index 3288db1d5f21..174cf92eea1d 100644 > > --- a/fs/read_write.c > > +++ b/fs/read_write.c > > @@ -1909,6 +1909,19 @@ int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in, > > bool same_inode = (inode_in == inode_out); > > int ret; > > > > + /* > > + * FICLONE/FICLONERANGE ioctls enforce that src and dest files are on > > + * the same mount. Practically, they only need to be on the same file > > + * system. We check this here rather than at the ioctl layers because > > + * this is effectively a limitation of the fielsystem implementations, > > + * not so much the API itself. Further, ->remap_file_range() can be > > + * called from syscalls that don't have cross device copy restrictions > > + * (such as copy_file_range()) and so we need to catch them before we > > + * do any damage. > > + */ > > + if (inode_in->i_sb != inode_out->i_sb) > > + return -EXDEV; > > + > > /* Don't touch certain kinds of inodes */ > > if (IS_IMMUTABLE(inode_out)) > > return -EPERM; > > @@ -2013,14 +2026,6 @@ loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, > > if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) > > return -EINVAL; > > > > - /* > > - * FICLONE/FICLONERANGE ioctls enforce that src and dest files are on > > - * the same mount. Practically, they only need to be on the same file > > - * system. > > - */ > > - if (inode_in->i_sb != inode_out->i_sb) > > - return -EXDEV; > > - > I think this is sort of backwards -- the checks should stay in do_clone_file_range, and vfs_copy_file_range should be calling that instead of directly calling ->remap_range(): vfs_copy_file_range() { file_start_write(...); ret = do_clone_file_range(...); if (ret > 0) return ret; ret = do_copy_file_range(...); file_end_write(...); return ret; } > That leaves {nfs42,cifs,btrfs}_remap_file_range() exposed to passing > files not of their own fs type let alone same sb when do_clone_file_range() > is called from ovl_copy_up_data(). ...and then I think this problem goes away. --D > Thanks, > Amir.