diff options
| author | Hugh Dickins <hugh@veritas.com> | 2007-02-10 01:46:13 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-02-11 10:51:34 -0800 |
| commit | 2e7842b887627c4319c4625d2b52fa6616fda2cd (patch) | |
| tree | 608123e38adff4cb19f756b0a67158ea30a15b18 /fs/ext2 | |
| parent | 9bbf81e4830db873300c1d0503b371b4f8a932ce (diff) | |
| download | lwn-2e7842b887627c4319c4625d2b52fa6616fda2cd.tar.gz lwn-2e7842b887627c4319c4625d2b52fa6616fda2cd.zip | |
[PATCH] fix umask when noACL kernel meets extN tuned for ACLs
Fix insecure default behaviour reported by Tigran Aivazian: if an ext2 or
ext3 or ext4 filesystem is tuned to mount with "acl", but mounted by a
kernel built without ACL support, then umask was ignored when creating
inodes - though root or user has umask 022, touch creates files as 0666,
and mkdir creates directories as 0777.
This appears to have worked right until 2.6.11, when a fix to the default
mode on symlinks (always 0777) assumed VFS applies umask: which it does,
unless the mount is marked for ACLs; but ext[234] set MS_POSIXACL in
s_flags according to s_mount_opt set according to def_mount_opts.
We could revert to the 2.6.10 ext[234]_init_acl (adding an S_ISLNK test);
but other filesystems only set MS_POSIXACL when ACLs are configured. We
could fix this at another level; but it seems most robust to avoid setting
the s_mount_opt flag in the first place (at the expense of more ifdefs).
Likewise don't set the XATTR_USER flag when built without XATTR support.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: <linux-ext4@vger.kernel.org>
Cc: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/ext2')
| -rw-r--r-- | fs/ext2/super.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 6347c2dbdd81..daaa243eee9b 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -708,10 +708,14 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) set_opt(sbi->s_mount_opt, GRPID); if (def_mount_opts & EXT2_DEFM_UID16) set_opt(sbi->s_mount_opt, NO_UID32); +#ifdef CONFIG_EXT2_FS_XATTR if (def_mount_opts & EXT2_DEFM_XATTR_USER) set_opt(sbi->s_mount_opt, XATTR_USER); +#endif +#ifdef CONFIG_EXT2_FS_POSIX_ACL if (def_mount_opts & EXT2_DEFM_ACL) set_opt(sbi->s_mount_opt, POSIX_ACL); +#endif if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) set_opt(sbi->s_mount_opt, ERRORS_PANIC); |