1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) International Business Machines Corp., 2004
4 * Copyright (c) Linux Test Project, 2004-2017
5 *
6 * DESCRIPTION
7 * hugeshmat03 - test for EACCES error
8 *
9 * ALGORITHM
10 * create a shared memory segment with root only read & write permissions
11 * fork a child process
12 * if child
13 * set the ID of the child process to that of "nobody"
14 * loop if that option was specified
15 * call shmat() using the TEST() macro
16 * check the errno value
17 * issue a PASS message if we get EACCES
18 * otherwise, the tests fails
19 * issue a FAIL message
20 * call cleanup
21 * if parent
22 * wait for child to exit
23 * remove the shared memory segment
24 *
25 * HISTORY
26 * 03/2001 - Written by Wayne Boyer
27 * 04/2004 - Updated by Robbie Williamson
28 *
29 * RESTRICTIONS
30 * test must be run at root
31 */
32
33 #include <limits.h>
34 #include "hugetlb.h"
35
36 static size_t shm_size;
37 static int shm_id_1 = -1;
38 static void *addr;
39 static uid_t ltp_uid;
40 static char *ltp_user = "nobody";
41
verify_hugeshmat(void)42 static void verify_hugeshmat(void)
43 {
44 int status;
45 pid_t pid;
46
47 switch (pid = SAFE_FORK()) {
48 case 0:
49 SAFE_SETUID(ltp_uid);
50
51 addr = shmat(shm_id_1, NULL, 0);
52 if (addr != (void *)-1) {
53 tst_res(TFAIL, "shmat succeeded unexpectedly");
54 return;
55 }
56 if (errno == EACCES) {
57 tst_res(TPASS | TERRNO, "shmat failed as expected");
58 } else {
59 tst_res(TFAIL | TERRNO, "shmat failed unexpectedly "
60 "- expect errno=EACCES, got");
61 }
62 break;
63 default:
64 SAFE_WAITPID(pid, &status, 0);
65 }
66 }
67
setup(void)68 static void setup(void)
69 {
70 long hpage_size;
71
72 if (tst_hugepages == 0)
73 tst_brk(TCONF, "No enough hugepages for testing.");
74
75 hpage_size = SAFE_READ_MEMINFO("Hugepagesize:") * 1024;
76
77 shm_size = hpage_size * tst_hugepages / 2;
78 update_shm_size(&shm_size);
79 shmkey = getipckey();
80 shm_id_1 = shmget(shmkey, shm_size,
81 SHM_HUGETLB | SHM_RW | IPC_CREAT | IPC_EXCL);
82 if (shm_id_1 == -1)
83 tst_brk(TBROK | TERRNO, "shmget");
84
85 ltp_uid = getuserid(ltp_user);
86 }
87
cleanup(void)88 static void cleanup(void)
89 {
90 rm_shm(shm_id_1);
91 }
92
93 static struct tst_test test = {
94 .needs_root = 1,
95 .forks_child = 1,
96 .needs_tmpdir = 1,
97 .options = (struct tst_option[]) {
98 {"s:", &nr_opt, "Set the number of the been allocated hugepages"},
99 {}
100 },
101 .test_all = verify_hugeshmat,
102 .setup = setup,
103 .cleanup = cleanup,
104 .hugepages = {128, TST_REQUEST},
105 };
106