out, err := cmd.CombinedOutput()
			t.Logf("%v: %v", cmd, err)

			if uid != 0 && setgroups {
				t.Logf("as non-root, expected permission error due to unprivileged gid_map")
				if !os.IsPermission(err) {
					if err == nil {
						t.Skipf("unexpected success: probably old kernel without security fix?")
					}
					if testenv.SyscallIsNotSupported(err) {

	dir, err := f.Stat()
	if err != nil {
		t.Fatalf("stat %s: %s", f.Name(), err)
	}

	linkname := f.Name() + "2"
	if err := Symlink(f.Name(), linkname); err != nil {
		if runtime.GOOS == "android" && IsPermission(err) {
			t.Skip("skipping test on Android; permission error creating symlink")
		}
		t.Fatalf("link %s -> %s: %v", f.Name(), linkname, err)
	}
	defer Remove(linkname)