From patchwork Thu Dec 3 23:57:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 11949959 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 1423AC3B183 for ; Fri, 4 Dec 2020 00:02:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E1CBD22285 for ; Fri, 4 Dec 2020 00:02:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388169AbgLDACM (ORCPT ); Thu, 3 Dec 2020 19:02:12 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:41698 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728138AbgLDACL (ORCPT ); Thu, 3 Dec 2020 19:02:11 -0500 Received: from ip5f5af0a0.dynamic.kabel-deutschland.de ([95.90.240.160] helo=wittgenstein.fritz.box) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1kkyXL-0007ka-79; Fri, 04 Dec 2020 00:01:23 +0000 From: Christian Brauner To: Alexander Viro , Christoph Hellwig , linux-fsdevel@vger.kernel.org Cc: John Johansen , James Morris , Mimi Zohar , Dmitry Kasatkin , Stephen Smalley , Casey Schaufler , Arnd Bergmann , Andreas Dilger , OGAWA Hirofumi , Geoffrey Thomas , Mrunal Patel , Josh Triplett , Andy Lutomirski , Theodore Tso , Alban Crequy , Tycho Andersen , David Howells , James Bottomley , Seth Forshee , =?utf-8?q?St=C3=A9phane_Graber?= , Aleksa Sarai , Lennart Poettering , "Eric W. Biederman" , smbarber@chromium.org, Phil Estes , Serge Hallyn , Kees Cook , Todd Kjos , Paul Moore , Jonathan Corbet , containers@lists.linux-foundation.org, linux-security-module@vger.kernel.org, linux-api@vger.kernel.org, linux-ext4@vger.kernel.org, linux-integrity@vger.kernel.org, selinux@vger.kernel.org, Christian Brauner , Christoph Hellwig Subject: [PATCH v4 05/40] fs: add attr_flags_to_mnt_flags helper Date: Fri, 4 Dec 2020 00:57:01 +0100 Message-Id: <20201203235736.3528991-6-christian.brauner@ubuntu.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201203235736.3528991-1-christian.brauner@ubuntu.com> References: <20201203235736.3528991-1-christian.brauner@ubuntu.com> MIME-Version: 1.0 Precedence: bulk List-ID: Add a simple helper to translate uapi MOUNT_ATTR_* flags to MNT_* flags which we will use in follow-up patches too. Suggested-by: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner Reviewed-by: Christoph Hellwig --- /* v2 */ patch not present /* v3 */ patch not present /* v4 */ patch introduced --- fs/namespace.c | 40 ++++++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 16 deletions(-) diff --git a/fs/namespace.c b/fs/namespace.c index 1a756d33c91a..b2a9eb7b43d3 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -3450,6 +3450,28 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name, return ret; } +#define FSMOUNT_VALID_FLAGS \ + (MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID | MOUNT_ATTR_NODEV | \ + MOUNT_ATTR_NOEXEC | MOUNT_ATTR__ATIME | MOUNT_ATTR_NODIRATIME) + +static unsigned int attr_flags_to_mnt_flags(u64 attr_flags) +{ + unsigned int mnt_flags = 0; + + if (attr_flags & MOUNT_ATTR_RDONLY) + mnt_flags |= MNT_READONLY; + if (attr_flags & MOUNT_ATTR_NOSUID) + mnt_flags |= MNT_NOSUID; + if (attr_flags & MOUNT_ATTR_NODEV) + mnt_flags |= MNT_NODEV; + if (attr_flags & MOUNT_ATTR_NOEXEC) + mnt_flags |= MNT_NOEXEC; + if (attr_flags & MOUNT_ATTR_NODIRATIME) + mnt_flags |= MNT_NODIRATIME; + + return mnt_flags; +} + /* * Create a kernel mount representation for a new, prepared superblock * (specified by fs_fd) and attach to an open_tree-like file descriptor. @@ -3472,24 +3494,10 @@ SYSCALL_DEFINE3(fsmount, int, fs_fd, unsigned int, flags, if ((flags & ~(FSMOUNT_CLOEXEC)) != 0) return -EINVAL; - if (attr_flags & ~(MOUNT_ATTR_RDONLY | - MOUNT_ATTR_NOSUID | - MOUNT_ATTR_NODEV | - MOUNT_ATTR_NOEXEC | - MOUNT_ATTR__ATIME | - MOUNT_ATTR_NODIRATIME)) + if (attr_flags & ~FSMOUNT_VALID_FLAGS) return -EINVAL; - if (attr_flags & MOUNT_ATTR_RDONLY) - mnt_flags |= MNT_READONLY; - if (attr_flags & MOUNT_ATTR_NOSUID) - mnt_flags |= MNT_NOSUID; - if (attr_flags & MOUNT_ATTR_NODEV) - mnt_flags |= MNT_NODEV; - if (attr_flags & MOUNT_ATTR_NOEXEC) - mnt_flags |= MNT_NOEXEC; - if (attr_flags & MOUNT_ATTR_NODIRATIME) - mnt_flags |= MNT_NODIRATIME; + mnt_flags = attr_flags_to_mnt_flags(attr_flags); switch (attr_flags & MOUNT_ATTR__ATIME) { case MOUNT_ATTR_STRICTATIME: