1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) International Business Machines Corp., 2001
4 *
5 * Ported by John George
6 */
7
8 /*
9 * Test that setregid() fails and sets the proper errno values when a
10 * non-root user attemps to change the real or effective group id to a
11 * value other than the current gid or the current effective gid.
12 */
13
14 #include <errno.h>
15 #include <pwd.h>
16 #include <grp.h>
17 #include <stdlib.h>
18
19 #include "tst_test.h"
20 #include "tst_uid.h"
21 #include "compat_tst_16.h"
22
23 static gid_t root_gid, nobody_gid, other_gid, neg_one = -1;
24
25 static struct passwd *ltpuser;
26
27 /*
28 * The following structure contains all test data. Each structure in the array
29 * is used for a separate test. The tests are executed in the for loop below.
30 */
31
32 static struct tcase {
33 gid_t *real_gid;
34 gid_t *eff_gid;
35 int exp_errno;
36 gid_t *exp_real_usr;
37 gid_t *exp_eff_usr;
38 char *test_msg;
39 } tcases[] = {
40 {
41 &neg_one, &root_gid, EPERM, &nobody_gid, &nobody_gid,
42 "After setregid(-1, root),"}, {
43 &neg_one, &other_gid, EPERM, &nobody_gid, &nobody_gid,
44 "After setregid(-1, other)"}, {
45 &root_gid, &neg_one, EPERM, &nobody_gid, &nobody_gid,
46 "After setregid(root,-1),"}, {
47 &other_gid, &neg_one, EPERM, &nobody_gid, &nobody_gid,
48 "After setregid(other, -1),"}, {
49 &root_gid, &other_gid, EPERM, &nobody_gid, &nobody_gid,
50 "After setregid(root, other)"}, {
51 &other_gid, &root_gid, EPERM, &nobody_gid, &nobody_gid,
52 "After setregid(other, root),"}
53 };
54
gid_verify(gid_t rg,gid_t eg,char * when)55 void gid_verify(gid_t rg, gid_t eg, char *when)
56 {
57 if ((getgid() != rg) || (getegid() != eg)) {
58 tst_res(TFAIL, "ERROR: %s real gid = %d; effective gid = %d",
59 when, getgid(), getegid());
60 tst_res(TINFO, "Expected: real gid = %d; effective gid = %d",
61 rg, eg);
62 return;
63 }
64
65 tst_res(TPASS, "real or effective gid wasn't modified as expected");
66 }
67
run(unsigned int n)68 static void run(unsigned int n)
69 {
70 struct tcase *tc = &tcases[n];
71
72 /* Set the real or effective group id */
73 TEST(SETREGID(*tc->real_gid, *tc->eff_gid));
74
75 if (TST_RET == -1) {
76 if (tc->exp_errno == TST_ERR) {
77 tst_res(TPASS | TTERRNO,
78 "setregid(%d, %d) failed as expected",
79 *tc->real_gid, *tc->eff_gid);
80 } else {
81 tst_res(TFAIL | TTERRNO,
82 "setregid(%d, %d) failed unexpectedly, expected %s",
83 *tc->real_gid, *tc->eff_gid,
84 tst_strerrno(tc->exp_errno));
85 }
86 } else {
87 tst_res(TFAIL,
88 "setregid(%d, %d) did not fail (ret: %ld) as expected (ret: -1).",
89 *tc->real_gid, *tc->eff_gid, TST_RET);
90 }
91 gid_verify(*tc->exp_real_usr, *tc->exp_eff_usr, tc->test_msg);
92 }
93
setup(void)94 static void setup(void)
95 {
96 gid_t test_groups[3];
97
98 ltpuser = SAFE_GETPWNAM("nobody");
99 nobody_gid = test_groups[0] = ltpuser->pw_gid;
100 root_gid = test_groups[1] = getgid();
101 tst_get_gids(test_groups, 2, 3);
102 other_gid = test_groups[2];
103
104 GID16_CHECK(root_gid, setregid);
105 GID16_CHECK(nobody_gid, setregid);
106 GID16_CHECK(other_gid, setregid);
107
108 SAFE_SETGID(ltpuser->pw_gid);
109 SAFE_SETUID(ltpuser->pw_uid);
110 }
111
112 static struct tst_test test = {
113 .tcnt = ARRAY_SIZE(tcases),
114 .needs_root = 1,
115 .test = run,
116 .setup = setup,
117 };
118