diff --git a/samples/memfs/fs.go b/samples/memfs/fs.go
index bfd9d4e..f78d5c9 100644
--- a/samples/memfs/fs.go
+++ b/samples/memfs/fs.go
@@ -58,7 +58,7 @@ func NewMemFS(
 	}
 
 	// Set up the root inode.
-	fs.inodes[fuse.RootInodeID] = newInode(os.ModeDir)
+	fs.inodes[fuse.RootInodeID] = newInode(0777 | os.ModeDir)
 
 	// Set up invariant checking.
 	fs.mu = syncutil.NewInvariantMutex(fs.checkInvariants)