From patchwork Thu Sep 22 15:17:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 12985404 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 13D0AC54EE9 for ; Thu, 22 Sep 2022 15:19:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232073AbiIVPTG (ORCPT ); Thu, 22 Sep 2022 11:19:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41274 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231941AbiIVPSl (ORCPT ); Thu, 22 Sep 2022 11:18:41 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3880FF088D; Thu, 22 Sep 2022 08:18:32 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C9E9963618; Thu, 22 Sep 2022 15:18:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9DF16C433D6; Thu, 22 Sep 2022 15:18:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1663859911; bh=fXVLvYpjfdPz+SBDkZu6K2V7Cz7KTZJUcoMolKUhUZA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WP9VpmaTbQtGSUmVWzDgh2XQDEscwUT602tudoG2znk21LS9k1c6qfHvuV5wed4u7 v58bSQ6XIPz53zvgjuHEtuOV+fD00YWaZ+1RfDBDHanyc4K0i5tTA2PswRzMHLkoGa hgTPbS+6IGGf7u1b7Y5DQP1vU7bn66tEPehbLq0GYElb18oHEOhS+LdWdwcjq17TTw 5iFGsnmixuKGiF7Afc9fLPIMmG4H3duwJCEobDJUjMYMK6JhMFfPgDmWl3AdRzCsmc OgU+F9hz+hhGEsv8guUY12rlMfct73+bCWKfOYwBS1z2MKxGILxveFW9ZW3FS6o3h3 9OWDgqo3MXTbA== From: Christian Brauner To: linux-fsdevel@vger.kernel.org Cc: Christian Brauner , Seth Forshee , Christoph Hellwig , Al Viro , Tyler Hicks , ecryptfs@vger.kernel.org Subject: [PATCH 20/29] ecryptfs: implement set acl method Date: Thu, 22 Sep 2022 17:17:18 +0200 Message-Id: <20220922151728.1557914-21-brauner@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220922151728.1557914-1-brauner@kernel.org> References: <20220922151728.1557914-1-brauner@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2885; i=brauner@kernel.org; h=from:subject; bh=fXVLvYpjfdPz+SBDkZu6K2V7Cz7KTZJUcoMolKUhUZA=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMSTr1FRnxUwuuhHrxJdwi0l6p+3tBXzrGyad35d2xnvPiisO Tq96O0pZGMS4GGTFFFkc2k3C5ZbzVGw2ytSAmcPKBDKEgYtTACbyzZiR4VpiM/9FaeMLNbO31VtYfD 99z0NSxyZq7p4OGb2Lfaue/2Rk2PGEL8ZUI8B5x0yh3BM6EQEPDzn81/m8XKCZ0SRwkY4/IwA= X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org The current way of setting and getting posix acls through the generic xattr interface is error prone and type unsafe. The vfs needs to interpret and fixup posix acls before storing or reporting it to userspace. Various hacks exist to make this work. The code is hard to understand and difficult to maintain in it's current form. Instead of making this work by hacking posix acls through xattr handlers we are building a dedicated posix acl api around the get and set inode operations. This removes a lot of hackiness and makes the codepaths easier to maintain. A lot of background can be found in [1]. In order to build a type safe posix api around get and set acl we need all filesystem to implement get and set acl. So far ecryptfs didn't implement get and set acl inode operations because it wanted easy access to the dentry. Now that we extended the set acl inode operation to take a dentry argument and added a new get acl inode operation that takes a dentry argument we can let ecryptfs implement get and set acl inode operations. Note, until the vfs has been switched to the new posix acl api this patch is a non-functional change. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Signed-off-by: Christian Brauner (Microsoft) --- fs/ecryptfs/inode.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 740312986388..c3d1ae688a19 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -1129,6 +1129,21 @@ static struct posix_acl *ecryptfs_get_acl(struct user_namespace *mnt_userns, posix_acl_xattr_name(type)); } +static int ecryptfs_set_acl(struct user_namespace *mnt_userns, + struct dentry *dentry, struct posix_acl *acl, + int type) +{ + int rc; + struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); + struct inode *lower_inode = d_inode(lower_dentry); + + rc = vfs_set_acl(&init_user_ns, lower_dentry, + posix_acl_xattr_name(type), acl); + if (!rc) + fsstack_copy_attr_all(d_inode(dentry), lower_inode); + return rc; +} + const struct inode_operations ecryptfs_symlink_iops = { .get_link = ecryptfs_get_link, .permission = ecryptfs_permission, @@ -1153,6 +1168,7 @@ const struct inode_operations ecryptfs_dir_iops = { .fileattr_get = ecryptfs_fileattr_get, .fileattr_set = ecryptfs_fileattr_set, .get_acl = ecryptfs_get_acl, + .set_acl = ecryptfs_set_acl, }; const struct inode_operations ecryptfs_main_iops = { @@ -1163,6 +1179,7 @@ const struct inode_operations ecryptfs_main_iops = { .fileattr_get = ecryptfs_fileattr_get, .fileattr_set = ecryptfs_fileattr_set, .get_acl = ecryptfs_get_acl, + .set_acl = ecryptfs_set_acl, }; static int ecryptfs_xattr_get(const struct xattr_handler *handler,