From: "Duane Griffin" Subject: [PATCH 5/6] ext3: tighten restrictions on inode flags Date: Thu, 19 Jun 2008 16:42:04 +0100 Message-ID: <1213890125-20186-6-git-send-email-duaneg@dghda.com> References: <1213890125-20186-1-git-send-email-duaneg@dghda.com> <1213890125-20186-2-git-send-email-duaneg@dghda.com> <1213890125-20186-3-git-send-email-duaneg@dghda.com> <1213890125-20186-4-git-send-email-duaneg@dghda.com> <1213890125-20186-5-git-send-email-duaneg@dghda.com> Cc: Andreas Dilger , "Aneesh Kumar K.V" , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, Duane Griffin To: akpm@linux-foundation.org Return-path: Received: from kumera.dghda.com ([80.68.90.171]:1515 "EHLO kumera.dghda.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759135AbYFSPmV (ORCPT ); Thu, 19 Jun 2008 11:42:21 -0400 In-Reply-To: <1213890125-20186-5-git-send-email-duaneg@dghda.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: 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 SECRM, UNRM, COMPR, SYNC, DIRTY, COMPRBLK, NOCOMPR, ECOMPR, INDEX, JOURNAL_DATA and NOTAIL being set on anything but regular files or directories. Introduce 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 -- This is v2 with types corrected, as suggested by Aneesh. The specific flags masked out here are those suggested by Andreas, as well as IMMUTABLE, which I included to match the behaviour of the existing code. --- fs/ext3/ialloc.c | 8 ++------ fs/ext3/ioctl.c | 3 +-- include/linux/ext3_fs.h | 22 ++++++++++++++++++++++ 3 files changed, 25 insertions(+), 8 deletions(-) diff --git a/fs/ext3/ialloc.c b/fs/ext3/ialloc.c index 1d9fe3f..c72d49d 100644 --- a/fs/ext3/ialloc.c +++ b/fs/ext3/ialloc.c @@ -559,12 +559,8 @@ got: ei->i_dir_start_lookup = 0; ei->i_disksize = 0; - ei->i_flags = EXT3_I(dir)->i_flags & EXT3_FL_INHERITED; - if (S_ISLNK(mode)) - ei->i_flags &= ~(EXT3_IMMUTABLE_FL|EXT3_APPEND_FL); - /* dirsync only applies to directories */ - if (!S_ISDIR(mode)) - ei->i_flags &= ~EXT3_DIRSYNC_FL; + ei->i_flags = + ext3_mask_flags(mode, EXT3_I(dir)->i_flags & EXT3_FL_INHERITED); #ifdef EXT3_FRAGMENTS ei->i_faddr = 0; ei->i_frag_no = 0; diff --git a/fs/ext3/ioctl.c b/fs/ext3/ioctl.c index 0d0c701..6d6534d 100644 --- a/fs/ext3/ioctl.c +++ b/fs/ext3/ioctl.c @@ -53,8 +53,7 @@ int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, goto flags_out; } - if (!S_ISDIR(inode->i_mode)) - flags &= ~EXT3_DIRSYNC_FL; + flags = ext3_mask_flags(inode->i_mode, flags); mutex_lock(&inode->i_mutex); /* Is it quota file? Do not allow user to mess with it */ diff --git a/include/linux/ext3_fs.h b/include/linux/ext3_fs.h index 140190d..e354c5f 100644 --- a/include/linux/ext3_fs.h +++ b/include/linux/ext3_fs.h @@ -185,6 +185,28 @@ struct ext3_group_desc EXT3_NOCOMPR_FL | EXT3_JOURNAL_DATA_FL |\ EXT3_NOTAIL_FL | EXT3_DIRSYNC_FL) +/* Flags that are inappropriate for regular files. */ +#define EXT3_REG_FLMASK (EXT3_DIRSYNC_FL | EXT3_TOPDIR_FL) + +/* Flags that are inappropriate for non-directories/regular files. */ +#define EXT3_OTHER_FLMASK (EXT3_SECRM_FL | EXT3_UNRM_FL | EXT3_COMPR_FL |\ + EXT3_SYNC_FL | EXT3_IMMUTABLE_FL | EXT3_APPEND_FL |\ + EXT3_DIRTY_FL | EXT3_COMPRBLK_FL | EXT3_NOCOMPR_FL|\ + EXT3_ECOMPR_FL | EXT3_INDEX_FL |\ + EXT3_JOURNAL_DATA_FL | EXT3_NOTAIL_FL |\ + EXT3_DIRSYNC_FL | EXT3_TOPDIR_FL) + +/* Mask out flags that are inappropriate for the given type of inode. */ +static inline __u32 ext3_mask_flags(umode_t mode, __u32 flags) +{ + if (S_ISDIR(mode)) + return flags; + else if (S_ISREG(mode)) + return flags & ~EXT3_REG_FLMASK; + else + return flags & ~EXT3_OTHER_FLMASK; +} + /* * Inode dynamic state flags */ -- 1.5.4.5