• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  *   Copyright (c) International Business Machines  Corp., 2002
3  *	06/2002 Written by Paul Larson
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  *   You should have received a copy of the GNU General Public License
16  *   along with this program;  if not, write to the Free Software Foundation,
17  *   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19 
20 /*
21  * Test Description:
22  *  Verify that,
23  *   1. mlock() fails with -1 return value and sets errno to ENOMEM,
24  *      if some of the specified address range does not correspond to
25  *      mapped pages in the address space of the process.
26  *   2. mlock() fails with -1 return value and sets errno to ENOMEM,
27  *      if (Linux  2.6.9  and  later)  the caller had a non-zero RLIMIT_MEMLOCK
28  *      soft resource limit, but tried to lock more memory than the limit
29  *      permitted.  This limit is not enforced if the process is privileged
30  *      (CAP_IPC_LOCK).
31  *   3. mlock() fails with -1 return value and sets errno to EPERM,
32  *      if (Linux 2.6.9 and later) the caller was not privileged (CAP_IPC_LOCK)
33  *      and its RLIMIT_MEMLOCK soft resource limit was 0.
34  */
35 
36 #include <errno.h>
37 #include <unistd.h>
38 #include <sys/mman.h>
39 #include <pwd.h>
40 
41 #include "test.h"
42 #include "safe_macros.h"
43 
44 char *TCID = "mlock02";
45 
46 #if !defined(UCLINUX)
47 
48 static void setup(void);
49 static void cleanup(void);
50 static void test_enomem1(void);
51 static void test_enomem2(void);
52 static void test_eperm(void);
53 static void mlock_verify(const void *, const size_t, const int);
54 
55 static size_t len;
56 static struct rlimit original;
57 static struct passwd *ltpuser;
58 
59 static void (*test_func[])(void) = { test_enomem1, test_enomem2, test_eperm };
60 
61 int TST_TOTAL = ARRAY_SIZE(test_func);
62 
main(int ac,char ** av)63 int main(int ac, char **av)
64 {
65 	int lc, i;
66 
67 	tst_parse_opts(ac, av, NULL, NULL);
68 
69 	setup();
70 
71 	for (lc = 0; TEST_LOOPING(lc); lc++) {
72 		tst_count = 0;
73 		for (i = 0; i < TST_TOTAL; i++)
74 			(*test_func[i])();
75 	}
76 
77 	cleanup();
78 	tst_exit();
79 }
80 
setup(void)81 static void setup(void)
82 {
83 	tst_require_root();
84 
85 	tst_sig(NOFORK, DEF_HANDLER, cleanup);
86 
87 	TEST_PAUSE;
88 
89 	ltpuser = SAFE_GETPWNAM(cleanup, "nobody");
90 
91 	len = getpagesize();
92 
93 	SAFE_GETRLIMIT(cleanup, RLIMIT_MEMLOCK, &original);
94 }
95 
test_enomem1(void)96 static void test_enomem1(void)
97 {
98 	void *addr;
99 	struct rlimit rl;
100 
101 	/*
102 	 * RLIMIT_MEMLOCK resource limit.
103 	 * In Linux kernels before 2.6.9, this limit controlled the amount
104 	 * of  memory that could be locked by a privileged process. Since
105 	 * Linux 2.6.9, no limits are placed on the amount of memory that a
106 	 * privileged process may lock, and this limit instead governs the
107 	 * amount of memory that an unprivileged process may lock. So here
108 	 * we set RLIMIT_MEMLOCK resource limit to RLIM_INFINITY when kernel
109 	 * is under 2.6.9, to make sure this ENOMEM error is indeed caused by
110 	 * that some of the specified address range does not correspond to
111 	 * mapped pages in the address space of the process.
112 	 */
113 	if ((tst_kvercmp(2, 6, 9)) < 0) {
114 		rl.rlim_cur = RLIM_INFINITY;
115 		rl.rlim_max = RLIM_INFINITY;
116 		SAFE_SETRLIMIT(cleanup, RLIMIT_MEMLOCK, &rl);
117 	}
118 
119 	addr = SAFE_MMAP(cleanup, NULL, len, PROT_READ,
120 			 MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
121 
122 	SAFE_MUNMAP(cleanup, addr, len);
123 
124 	mlock_verify(addr, len, ENOMEM);
125 }
126 
test_enomem2(void)127 static void test_enomem2(void)
128 {
129 	void *addr;
130 	struct rlimit rl;
131 
132 	if ((tst_kvercmp(2, 6, 9)) < 0) {
133 		tst_resm(TCONF,
134 			 "ENOMEM error value test for this condition needs "
135 			 "kernel 2.6.9 or higher");
136 		return;
137 	}
138 
139 	rl.rlim_max = len - 1;
140 	rl.rlim_cur = len - 1;
141 	SAFE_SETRLIMIT(cleanup, RLIMIT_MEMLOCK, &rl);
142 
143 	addr = SAFE_MMAP(cleanup, NULL, len, PROT_READ,
144 			 MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
145 
146 	SAFE_SETEUID(cleanup, ltpuser->pw_uid);
147 
148 	mlock_verify(addr, len, ENOMEM);
149 
150 	SAFE_SETEUID(cleanup, 0);
151 
152 	SAFE_MUNMAP(cleanup, addr, len);
153 
154 	SAFE_SETRLIMIT(cleanup, RLIMIT_MEMLOCK, &original);
155 }
156 
test_eperm(void)157 static void test_eperm(void)
158 {
159 	void *addr;
160 	struct rlimit rl;
161 
162 	if ((tst_kvercmp(2, 6, 9)) < 0) {
163 		tst_resm(TCONF,
164 			 "EPERM error value test needs kernel 2.6.9 or higher");
165 		return;
166 	}
167 
168 	rl.rlim_max = 0;
169 	rl.rlim_cur = 0;
170 	SAFE_SETRLIMIT(cleanup, RLIMIT_MEMLOCK, &rl);
171 
172 	addr = SAFE_MMAP(cleanup, NULL, len, PROT_READ,
173 			 MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
174 
175 	SAFE_SETEUID(cleanup, ltpuser->pw_uid);
176 
177 	mlock_verify(addr, len, EPERM);
178 
179 	SAFE_SETEUID(cleanup, 0);
180 
181 	SAFE_MUNMAP(cleanup, addr, len);
182 
183 	SAFE_SETRLIMIT(cleanup, RLIMIT_MEMLOCK, &original);
184 }
185 
mlock_verify(const void * addr,const size_t len,const int error)186 static void mlock_verify(const void *addr, const size_t len, const int error)
187 {
188 	TEST(mlock(addr, len));
189 
190 	if (TEST_RETURN != -1) {
191 		tst_resm(TFAIL, "mlock succeeded unexpectedly");
192 		return;
193 	}
194 
195 	if (TEST_ERRNO != error) {
196 		tst_resm(TFAIL | TTERRNO,
197 			 "mlock didn't fail as expected; expected - %d : %s",
198 			 error, strerror(error));
199 	} else {
200 		tst_resm(TPASS | TTERRNO, "mlock failed as expected");
201 	}
202 }
203 
cleanup(void)204 static void cleanup(void)
205 {
206 }
207 
208 #else
209 
210 int TST_TOTAL = 1;
211 
main(void)212 int main(void)
213 {
214 	tst_brkm(TCONF, NULL, "test is not available on uClinux");
215 }
216 
217 #endif /* if !defined(UCLINUX) */
218