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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8E8DFC54EED for ; Mon, 30 Jan 2023 09:16:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236167AbjA3JQU (ORCPT ); Mon, 30 Jan 2023 04:16:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51582 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235394AbjA3JQT (ORCPT ); Mon, 30 Jan 2023 04:16:19 -0500 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 271B91ABD4; Mon, 30 Jan 2023 01:16:19 -0800 (PST) Received: by verein.lst.de (Postfix, from userid 2407) id 524FF68BEB; Mon, 30 Jan 2023 10:16:15 +0100 (CET) Date: Mon, 30 Jan 2023 10:16:15 +0100 From: Christoph Hellwig To: Christian Brauner Cc: linux-fsdevel@vger.kernel.org, Christoph Hellwig , Al Viro , Seth Forshee , linux-erofs@lists.ozlabs.org, Jan Kara , linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-mtd@lists.infradead.org, ocfs2-devel@oss.oracle.com, reiserfs-devel@vger.kernel.org Subject: Re: [PATCH 00/12] acl: remove remaining posix acl handlers Message-ID: <20230130091615.GB5178@lst.de> References: <20230125-fs-acl-remove-generic-xattr-handlers-v1-0-6cf155b492b6@kernel.org> <20230130091052.72zglqecqvom7hin@wittgenstein> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230130091052.72zglqecqvom7hin@wittgenstein> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon, Jan 30, 2023 at 10:10:52AM +0100, Christian Brauner wrote: > However, a few filesystems still rely on the ->list() method of the > generix POSIX ACL xattr handlers in their ->listxattr() inode operation. > This is a very limited set of filesystems. For most of them there is no > dependence on the generic POSIX ACL xattr handler in any way. > > In addition, during inode initalization in inode_init_always() the > registered xattr handlers in sb->s_xattr are used to raise IOP_XATTR in > inode->i_opflags. > > With the incoming removal of the legacy POSIX ACL handlers it is at > least possible for a filesystem to only implement POSIX ACLs but no > other xattrs. If that were to happen we would miss to raise IOP_XATTR > because sb->s_xattr would be NULL. While there currently is no such > filesystem we should still make sure that this just works should it ever > happen in the future. Now the real questions is: do we care? Once Posix ACLs use an entirely separate path, nothing should rely on IOP_XATTR for them. So instead I think we're better off auditing all users of IOP_XATTR and making sure that nothing relies on them for ACLs, as we've very much split the VFS concept of ACLs from that from xattrs otherwise.