Btrfs: fix extent state leak from tree log

It's possible that btrfs_sync_log() bails out after one of the two
btrfs_write_marked_extents() which convert extent state's state bit into
EXTENT_NEED_WAIT from EXTENT_DIRTY/EXTENT_NEW, however only EXTENT_DIRTY
and EXTENT_NEW are searched by free_log_tree() so that those extent states
with EXTENT_NEED_WAIT lead to memory leak.

cc: <stable@vger.kernel.org>
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

fs/btrfs/tree-log.c

@@ -3026,13 +3026,14 @@ static void free_log_tree(struct btrfs_trans_handle *trans,
 
 	while (1) {
 		ret = find_first_extent_bit(&log->dirty_log_pages,
-				0, &start, &end, EXTENT_DIRTY | EXTENT_NEW,
+				0, &start, &end,
+				EXTENT_DIRTY | EXTENT_NEW | EXTENT_NEED_WAIT,
 				NULL);
 		if (ret)
 			break;
 
 		clear_extent_bits(&log->dirty_log_pages, start, end,
-				  EXTENT_DIRTY | EXTENT_NEW);
+				  EXTENT_DIRTY | EXTENT_NEW | EXTENT_NEED_WAIT);
 	}
 
 	/*