1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) International Business Machines Corp., 2001
4 * 07/2001 ported by John George
5 * Copyright (C) 2021 SUSE LLC <mdoucha@suse.cz>
6 */
7
8 /*\
9 * [Description]
10 *
11 * Test that a non-root user can change the real, effective and saved uid
12 * values through the setresuid system call.
13 */
14
15 #define _GNU_SOURCE 1
16 #include <sys/types.h>
17 #include <pwd.h>
18
19 #include "tst_test.h"
20 #include "tst_uid.h"
21 #include "compat_tst_16.h"
22
23 static uid_t nobody_uid, other_uid, neg_one = -1;
24
25 static struct test_data_t {
26 uid_t *real_uid;
27 uid_t *eff_uid;
28 uid_t *sav_uid;
29 uid_t *exp_real_uid;
30 uid_t *exp_eff_uid;
31 uid_t *exp_sav_uid;
32 char *test_msg;
33 } test_data[] = {
34 {&neg_one, &neg_one, &other_uid, &nobody_uid, &other_uid, &other_uid,
35 "setresuid(-1, -1, other)"},
36 {&neg_one, &nobody_uid, &neg_one, &nobody_uid, &nobody_uid, &other_uid,
37 "setresuid(-1, nobody -1)"},
38 {&other_uid, &neg_one, &neg_one, &other_uid, &nobody_uid, &other_uid,
39 "setresuid(other, -1 -1)"},
40 /* Return to initial state */
41 {&nobody_uid, &other_uid, &nobody_uid, &nobody_uid, &other_uid,
42 &nobody_uid, "setresuid(nobody, other, nobody)"},
43 };
44
setup(void)45 static void setup(void)
46 {
47 uid_t test_users[2];
48 struct passwd *pw = SAFE_GETPWNAM("nobody");
49
50 nobody_uid = test_users[0] = pw->pw_uid;
51 tst_get_uids(test_users, 1, 2);
52 other_uid = test_users[1];
53
54 UID16_CHECK(nobody_uid, setresuid);
55 UID16_CHECK(other_uid, setresuid);
56
57 SAFE_SETRESUID(nobody_uid, other_uid, nobody_uid);
58 }
59
run(unsigned int n)60 static void run(unsigned int n)
61 {
62 const struct test_data_t *tc = test_data + n;
63
64 TST_EXP_PASS_SILENT(SETRESUID(*tc->real_uid, *tc->eff_uid,
65 *tc->sav_uid), "%s", tc->test_msg);
66
67 if (!TST_PASS)
68 return;
69
70 if (tst_check_resuid(tc->test_msg, *tc->exp_real_uid,
71 *tc->exp_eff_uid, *tc->exp_sav_uid))
72 tst_res(TPASS, "%s works as expected", tc->test_msg);
73 }
74
75 static struct tst_test test = {
76 .test = run,
77 .tcnt = ARRAY_SIZE(test_data),
78 .setup = setup,
79 .needs_root = 1,
80 };
81