ext3: don't inherit inappropriate inode flags from parent

At present INDEX is the only flag that new ext3 inodes do NOT inherit from
their parent.  In addition prevent the flags DIRTY, ECOMPR, IMAGIC and
TOPDIR from being inherited.  List inheritable flags explicitly to prevent
future flags from accidentally being inherited.

This fixes the TOPDIR flag inheritance bug reported at
http://bugzilla.kernel.org/show_bug.cgi?id=9866.

Signed-off-by: Duane Griffin <duaneg@dghda.com>
Acked-by: Andreas Dilger <adilger@sun.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/ext3/ialloc.c

@@ -559,7 +559,7 @@ got:
 	ei->i_dir_start_lookup = 0;
 	ei->i_disksize = 0;
 
-	ei->i_flags = EXT3_I(dir)->i_flags & ~EXT3_INDEX_FL;
+	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 */

include/linux/ext3_fs.h

@@ -178,6 +178,13 @@ struct ext3_group_desc
 #define EXT3_FL_USER_VISIBLE		0x0003DFFF /* User visible flags */
 #define EXT3_FL_USER_MODIFIABLE		0x000380FF /* User modifiable flags */
 
+/* Flags that should be inherited by new inodes from their parent. */
+#define EXT3_FL_INHERITED (EXT3_SECRM_FL | EXT3_UNRM_FL | EXT3_COMPR_FL |\
+			   EXT3_SYNC_FL | EXT3_IMMUTABLE_FL | EXT3_APPEND_FL |\
+			   EXT3_NODUMP_FL | EXT3_NOATIME_FL | EXT3_COMPRBLK_FL|\
+			   EXT3_NOCOMPR_FL | EXT3_JOURNAL_DATA_FL |\
+			   EXT3_NOTAIL_FL | EXT3_DIRSYNC_FL)
+
 /*
  * Inode dynamic state flags
  */