From patchwork Fri Jan 9 20:24:54 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 17587 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id 6B99ADE491 for ; Sat, 10 Jan 2009 07:25:24 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753994AbZAIUZX (ORCPT ); Fri, 9 Jan 2009 15:25:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754415AbZAIUZX (ORCPT ); Fri, 9 Jan 2009 15:25:23 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:51107 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753994AbZAIUZV (ORCPT ); Fri, 9 Jan 2009 15:25:21 -0500 Received: from imap1.linux-foundation.org (imap1.linux-foundation.org [140.211.169.55]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id n09KOtH4022364 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 9 Jan 2009 12:24:56 -0800 Received: from localhost.localdomain (localhost [127.0.0.1]) by imap1.linux-foundation.org (8.13.5.20060308/8.13.5/Debian-3ubuntu1.1) with ESMTP id n09KOtOA021740; Fri, 9 Jan 2009 12:24:55 -0800 Message-Id: <200901092024.n09KOtOA021740@imap1.linux-foundation.org> Subject: [patch 3/3] ext4: tighten restrictions on inode flags To: tytso@mit.edu Cc: linux-ext4@vger.kernel.org, akpm@linux-foundation.org, duaneg@dghda.com, adilger@sun.com From: akpm@linux-foundation.org Date: Fri, 09 Jan 2009 12:24:54 -0800 X-Spam-Status: No, hits=-3.412 required=5 tests=AWL, BAYES_00, OSDL_HEADER_SUBJECT_BRACKETED X-Spam-Checker-Version: SpamAssassin 3.2.4-osdl_revision__1.47__ X-MIMEDefang-Filter: lf$Revision: 1.188 $ X-Scanned-By: MIMEDefang 2.63 on 140.211.169.13 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org From: "Duane Griffin" At the moment there are few restrictions on which flags may be set on which inodes. Specifically DIRSYNC may only be set on directories and IMMUTABLE and APPEND may not be set on links. Tighten that to disallow TOPDIR being set on non-directories and only NODUMP and NOATIME to be set on non-regular file, non-directories. Introduces a flags masking function which masks flags based on mode and use it during inode creation and when flags are set via the ioctl to facilitate future consistency. Signed-off-by: Duane Griffin Acked-by: Andreas Dilger Cc: Signed-off-by: Andrew Morton --- fs/ext4/ext4.h | 17 +++++++++++++++++ fs/ext4/ialloc.c | 14 +++++--------- fs/ext4/ioctl.c | 3 +-- 3 files changed, 23 insertions(+), 11 deletions(-) diff -puN fs/ext4/ext4.h~ext4-tighten-restrictions-on-inode-flags fs/ext4/ext4.h --- a/fs/ext4/ext4.h~ext4-tighten-restrictions-on-inode-flags +++ a/fs/ext4/ext4.h @@ -256,6 +256,23 @@ struct flex_groups { EXT4_JOURNAL_DATA_FL | EXT4_NOTAIL_FL|\ EXT4_DIRSYNC_FL) +/* Flags that are appropriate for regular files (all but dir-specific ones). */ +#define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL)) + +/* Flags that are appropriate for non-directories/regular files. */ +#define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL) + +/* Mask out flags that are inappropriate for the given type of inode. */ +static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags) +{ + if (S_ISDIR(mode)) + return flags; + else if (S_ISREG(mode)) + return flags & EXT4_REG_FLMASK; + else + return flags & EXT4_OTHER_FLMASK; +} + /* * Inode dynamic state flags */ diff -puN fs/ext4/ialloc.c~ext4-tighten-restrictions-on-inode-flags fs/ext4/ialloc.c --- a/fs/ext4/ialloc.c~ext4-tighten-restrictions-on-inode-flags +++ a/fs/ext4/ialloc.c @@ -874,16 +874,12 @@ got: ei->i_disksize = 0; /* - * Don't inherit extent flag from directory. We set extent flag on - * newly created directory and file only if -o extent mount option is - * specified + * Don't inherit extent flag from directory, amongst others. We set + * extent flag on newly created directory and file only if -o extent + * mount option is specified */ - ei->i_flags = EXT4_I(dir)->i_flags & EXT4_FL_INHERITED; - if (S_ISLNK(mode)) - ei->i_flags &= ~(EXT4_IMMUTABLE_FL|EXT4_APPEND_FL); - /* dirsync only applies to directories */ - if (!S_ISDIR(mode)) - ei->i_flags &= ~EXT4_DIRSYNC_FL; + ei->i_flags = + ext4_mask_flags(mode, EXT4_I(dir)->i_flags & EXT4_FL_INHERITED); ei->i_file_acl = 0; ei->i_dtime = 0; ei->i_block_group = group; diff -puN fs/ext4/ioctl.c~ext4-tighten-restrictions-on-inode-flags fs/ext4/ioctl.c --- a/fs/ext4/ioctl.c~ext4-tighten-restrictions-on-inode-flags +++ a/fs/ext4/ioctl.c @@ -48,8 +48,7 @@ long ext4_ioctl(struct file *filp, unsig if (err) return err; - if (!S_ISDIR(inode->i_mode)) - flags &= ~EXT4_DIRSYNC_FL; + flags = ext4_mask_flags(inode->i_mode, flags); err = -EPERM; mutex_lock(&inode->i_mutex);