From 2e7842b887627c4319c4625d2b52fa6616fda2cd Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Sat, 10 Feb 2007 01:46:13 -0800 Subject: [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 Cc: Tigran Aivazian Cc: Cc: Andreas Gruenbacher Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ext2/super.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'fs/ext2') 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); -- cgit v1.2.3