1 /*
2 * Copyright (c) International Business Machines Corp., 2004
3 * Copyright (c) Linux Test Project, 2004-2017
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
14 */
15
16 /*
17 * DESCRIPTION
18 * hugeshmat03 - test for EACCES error
19 *
20 * ALGORITHM
21 * create a shared memory segment with root only read & write permissions
22 * fork a child process
23 * if child
24 * set the ID of the child process to that of "nobody"
25 * loop if that option was specified
26 * call shmat() using the TEST() macro
27 * check the errno value
28 * issue a PASS message if we get EACCES
29 * otherwise, the tests fails
30 * issue a FAIL message
31 * call cleanup
32 * if parent
33 * wait for child to exit
34 * remove the shared memory segment
35 *
36 * HISTORY
37 * 03/2001 - Written by Wayne Boyer
38 * 04/2004 - Updated by Robbie Williamson
39 *
40 * RESTRICTIONS
41 * test must be run at root
42 */
43
44 #include <limits.h>
45 #include "hugetlb.h"
46
47 static size_t shm_size;
48 static int shm_id_1 = -1;
49 static void *addr;
50 static uid_t ltp_uid;
51 static char *ltp_user = "nobody";
52
53 static long hugepages = 128;
54
55 static struct tst_option options[] = {
56 {"s:", &nr_opt, "-s num Set the number of the been allocated hugepages"},
57 {NULL, NULL, NULL}
58 };
59
verify_hugeshmat(void)60 static void verify_hugeshmat(void)
61 {
62 int status;
63 pid_t pid;
64
65 switch (pid = SAFE_FORK()) {
66 case 0:
67 SAFE_SETUID(ltp_uid);
68
69 addr = shmat(shm_id_1, NULL, 0);
70 if (addr != (void *)-1) {
71 tst_res(TFAIL, "shmat succeeded unexpectedly");
72 return;
73 }
74 if (errno == EACCES) {
75 tst_res(TPASS | TERRNO, "shmat failed as expected");
76 } else {
77 tst_res(TFAIL | TERRNO, "shmat failed unexpectedly "
78 "- expect errno=EACCES, got");
79 }
80 break;
81 default:
82 SAFE_WAITPID(pid, &status, 0);
83 }
84 }
85
setup(void)86 static void setup(void)
87 {
88 long hpage_size;
89
90 save_nr_hugepages();
91 if (nr_opt)
92 hugepages = SAFE_STRTOL(nr_opt, 0, LONG_MAX);
93
94 set_sys_tune("nr_hugepages", hugepages, 1);
95 hpage_size = SAFE_READ_MEMINFO("Hugepagesize:") * 1024;
96
97 shm_size = hpage_size * hugepages / 2;
98 update_shm_size(&shm_size);
99 shmkey = getipckey();
100 shm_id_1 = shmget(shmkey, shm_size,
101 SHM_HUGETLB | SHM_RW | IPC_CREAT | IPC_EXCL);
102 if (shm_id_1 == -1)
103 tst_brk(TBROK | TERRNO, "shmget");
104
105 ltp_uid = getuserid(ltp_user);
106 }
107
cleanup(void)108 static void cleanup(void)
109 {
110 rm_shm(shm_id_1);
111 restore_nr_hugepages();
112 }
113
114 static struct tst_test test = {
115 .needs_root = 1,
116 .forks_child = 1,
117 .needs_tmpdir = 1,
118 .options = options,
119 .test_all = verify_hugeshmat,
120 .setup = setup,
121 .cleanup = cleanup,
122 };
123