xref: /aosp_15_r20/external/ltp/testcases/kernel/containers/utsname/utsname04.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2023 SUSE LLC Andrea Cervesato <[email protected]>
4  */
5 
6 /*\
7  * [Description]
8  *
9  * Drop root privileges, create a container with CLONE_NEWUTS and verify that
10  * we receive a permission error.
11  */
12 
13 #define _GNU_SOURCE
14 
15 #include <pwd.h>
16 #include "tst_test.h"
17 #include "lapi/sched.h"
18 
19 static char *str_op;
20 
run(void)21 static void run(void)
22 {
23 	const struct tst_clone_args cargs = {
24 		.flags = CLONE_NEWUTS,
25 		.exit_signal = SIGCHLD,
26 	};
27 	struct passwd *pw;
28 
29 	tst_res(TINFO, "Dropping root privileges");
30 
31 	pw = SAFE_GETPWNAM("nobody");
32 	SAFE_SETRESUID(pw->pw_uid, pw->pw_uid, pw->pw_uid);
33 
34 	if (!str_op || !strcmp(str_op, "clone")) {
35 		TEST(tst_clone(&cargs));
36 
37 		if (TST_RET == -1)
38 			tst_res(TPASS, "clone3() fails as expected");
39 		else if (TST_RET == -2)
40 			tst_res(TPASS, "clone() fails as expected");
41 		else
42 			tst_res(TFAIL, "tst_clone returns %ld", TST_RET);
43 
44 		TST_EXP_PASS(errno == EPERM);
45 	} else {
46 		if (!SAFE_FORK()) {
47 			TST_EXP_EQ_LI(unshare(CLONE_NEWUTS), -1);
48 			TST_EXP_PASS(errno == EPERM);
49 			return;
50 		}
51 	}
52 }
53 
54 static struct tst_test test = {
55 	.test_all = run,
56 	.needs_root = 1,
57 	.forks_child = 1,
58 	.needs_checkpoints = 1,
59 	.options = (struct tst_option[]) {
60 		{ "m:", &str_op, "Test execution mode <clone|unshare>" },
61 		{},
62 	},
63 };
64