1 /* $NetBSD: t_mlock.c,v 1.8 2020/01/24 08:45:16 skrll Exp $ */
2
3 /*-
4 * Copyright (c) 2012 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jukka Ruohonen.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31 #include <sys/cdefs.h>
32 __RCSID("$NetBSD: t_mlock.c,v 1.8 2020/01/24 08:45:16 skrll Exp $");
33
34 #include <sys/mman.h>
35 #include <sys/resource.h>
36 #include <sys/sysctl.h>
37 #include <sys/wait.h>
38
39 #include <errno.h>
40 #include <atf-c.h>
41 #include <stdint.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <unistd.h>
46
47 static long page = 0;
48
49 ATF_TC(mlock_clip);
ATF_TC_HEAD(mlock_clip,tc)50 ATF_TC_HEAD(mlock_clip, tc)
51 {
52 atf_tc_set_md_var(tc, "descr", "Test with mlock(2) that UVM only "
53 "clips if the clip address is within the entry (PR kern/44788)");
54 }
55
ATF_TC_BODY(mlock_clip,tc)56 ATF_TC_BODY(mlock_clip, tc)
57 {
58 void *buf;
59 int err1, err2;
60
61 buf = malloc(page);
62 ATF_REQUIRE(buf != NULL);
63 fprintf(stderr, "mlock_clip: buf = %p (page=%ld)\n", buf, page);
64
65 if (page < 1024)
66 atf_tc_skip("page size too small");
67
68 for (size_t i = page; i >= 1; i = i - 1024) {
69 err1 = mlock(buf, page - i);
70 if (err1 != 0)
71 fprintf(stderr, "mlock_clip: page=%ld i=%zu,"
72 " mlock(%p, %ld): %s\n", page, i, buf, page - i,
73 strerror(errno));
74 err2 = munlock(buf, page - i);
75 if (err2 != 0)
76 fprintf(stderr, "mlock_clip: page=%ld i=%zu,"
77 " munlock(%p, %ld): %s (mlock %s)\n", page, i,
78 buf, page - i, strerror(errno), err1?"failed":"ok");
79 }
80
81 free(buf);
82 }
83
84 ATF_TC(mlock_err);
ATF_TC_HEAD(mlock_err,tc)85 ATF_TC_HEAD(mlock_err, tc)
86 {
87 atf_tc_set_md_var(tc, "descr",
88 "Test error conditions in mlock(2) and munlock(2)");
89 }
90
ATF_TC_BODY(mlock_err,tc)91 ATF_TC_BODY(mlock_err, tc)
92 {
93 void *invalid_ptr;
94 void *buf;
95 int mlock_err, munlock_err;
96
97 /*
98 * Any bad address must return ENOMEM (for lock & unlock)
99 */
100 errno = 0;
101 ATF_REQUIRE_ERRNO(ENOMEM, mlock(NULL, page) == -1);
102
103 errno = 0;
104 ATF_REQUIRE_ERRNO(ENOMEM, mlock((char *)0, page) == -1);
105
106 errno = 0;
107 ATF_REQUIRE_ERRNO(ENOMEM, mlock((char *)-1, page) == -1);
108
109 errno = 0;
110 ATF_REQUIRE_ERRNO(ENOMEM, munlock(NULL, page) == -1);
111
112 errno = 0;
113 ATF_REQUIRE_ERRNO(ENOMEM, munlock((char *)0, page) == -1);
114
115 errno = 0;
116 ATF_REQUIRE_ERRNO(ENOMEM, munlock((char *)-1, page) == -1);
117
118 buf = malloc(page);
119 ATF_REQUIRE(buf != NULL);
120 fprintf(stderr, "mlock_err: buf = %p (page=%ld)\n", buf, page);
121
122 /*
123 * unlocking memory that is not locked is an error...
124 */
125
126 errno = 0;
127 ATF_REQUIRE_ERRNO(ENOMEM, munlock(buf, page) == -1);
128
129 /*
130 * These are permitted to fail (EINVAL) but do not on NetBSD
131 */
132 mlock_err = mlock((void *)(((uintptr_t)buf) + page/3), page/5);
133 if (mlock_err != 0)
134 fprintf(stderr, "mlock_err: mlock(%p, %ld): %d [%d] %s\n",
135 (void *)(((uintptr_t)buf) + page/3), page/5, mlock_err,
136 errno, strerror(errno));
137 ATF_REQUIRE(mlock_err == 0);
138 munlock_err= munlock((void *)(((uintptr_t)buf) + page/3), page/5);
139 if (munlock_err != 0)
140 fprintf(stderr, "mlock_err: munlock(%p, %ld): %d [%d] %s\n",
141 (void *)(((uintptr_t)buf) + page/3), page/5, munlock_err,
142 errno, strerror(errno));
143 ATF_REQUIRE(munlock_err == 0);
144
145 (void)free(buf);
146
147 /*
148 * Try to create a pointer to an unmapped page - first after current
149 * brk will likely do.
150 */
151 invalid_ptr = (void*)(((uintptr_t)sbrk(0)+page) & ~(page-1));
152 printf("testing with (hopefully) invalid pointer %p\n", invalid_ptr);
153
154 errno = 0;
155 ATF_REQUIRE_ERRNO(ENOMEM, mlock(invalid_ptr, page) == -1);
156
157 errno = 0;
158 ATF_REQUIRE_ERRNO(ENOMEM, munlock(invalid_ptr, page) == -1);
159 }
160
161 ATF_TC(mlock_limits);
ATF_TC_HEAD(mlock_limits,tc)162 ATF_TC_HEAD(mlock_limits, tc)
163 {
164 atf_tc_set_md_var(tc, "descr", "Test system limits with mlock(2)");
165 }
166
ATF_TC_BODY(mlock_limits,tc)167 ATF_TC_BODY(mlock_limits, tc)
168 {
169 struct rlimit res;
170 void *buf;
171 pid_t pid;
172 int sta;
173
174 buf = malloc(page);
175 ATF_REQUIRE(buf != NULL);
176 fprintf(stderr, "mlock_limits: buf = %p (page=%ld)\n", buf, page);
177
178 pid = fork();
179 ATF_REQUIRE(pid >= 0);
180
181 if (pid == 0) {
182
183 for (ssize_t i = page; i >= 2; i -= 100) {
184
185 res.rlim_cur = i - 1;
186 res.rlim_max = i - 1;
187
188 (void)fprintf(stderr, "trying to lock %zu bytes "
189 "with %zu byte limit\n", i, (size_t)res.rlim_cur);
190
191 if (setrlimit(RLIMIT_MEMLOCK, &res) != 0)
192 _exit(EXIT_FAILURE);
193
194 errno = 0;
195
196 if ((sta = mlock(buf, i)) != -1 || errno != EAGAIN) {
197 fprintf(stderr, "mlock(%p, %zu): %d [%d] %s\n",
198 buf, i, sta, errno, strerror(errno));
199 (void)munlock(buf, i);
200 _exit(EXIT_FAILURE);
201 }
202 }
203
204 _exit(EXIT_SUCCESS);
205 }
206
207 (void)wait(&sta);
208
209 if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS)
210 atf_tc_fail("mlock(2) locked beyond system limits");
211
212 free(buf);
213 }
214
215 ATF_TC(mlock_mmap);
ATF_TC_HEAD(mlock_mmap,tc)216 ATF_TC_HEAD(mlock_mmap, tc)
217 {
218 atf_tc_set_md_var(tc, "descr", "Test mlock(2)-mmap(2) interaction");
219 }
220
ATF_TC_BODY(mlock_mmap,tc)221 ATF_TC_BODY(mlock_mmap, tc)
222 {
223 static const int flags = MAP_ANON | MAP_PRIVATE | MAP_WIRED;
224 void *buf;
225
226 /*
227 * Make a wired RW mapping and check that mlock(2)
228 * does not fail for the (already locked) mapping.
229 */
230 buf = mmap(NULL, page, PROT_READ | PROT_WRITE, flags, -1, 0);
231
232 if (buf == MAP_FAILED)
233 fprintf(stderr,
234 "mlock_mmap: mmap(NULL, %ld, %#x, %#x, -1, 0): MAP_FAILED"
235 " [%d] %s\n", page, PROT_READ | PROT_WRITE, flags, errno,
236 strerror(errno));
237
238 ATF_REQUIRE(buf != MAP_FAILED);
239
240 fprintf(stderr, "mlock_mmap: buf=%p, page=%ld\n", buf, page);
241
242 ATF_REQUIRE(mlock(buf, page) == 0);
243 ATF_REQUIRE(munlock(buf, page) == 0);
244 ATF_REQUIRE(munmap(buf, page) == 0);
245 ATF_REQUIRE(munlock(buf, page) != 0);
246
247 fprintf(stderr, "mlock_mmap: first test succeeded\n");
248
249 /*
250 * But it should be impossible to mlock(2) a PROT_NONE mapping.
251 */
252 buf = mmap(NULL, page, PROT_NONE, flags, -1, 0);
253
254 if (buf == MAP_FAILED)
255 fprintf(stderr,
256 "mlock_mmap: mmap(NULL, %ld, %#x, %#x, -1, 0): MAP_FAILED"
257 " [%d] %s\n", page, PROT_NONE, flags, errno,
258 strerror(errno));
259
260 ATF_REQUIRE(buf != MAP_FAILED);
261 ATF_REQUIRE(mlock(buf, page) != 0);
262 ATF_REQUIRE(munmap(buf, page) == 0);
263
264 fprintf(stderr, "mlock_mmap: second test succeeded\n");
265 }
266
267 ATF_TC(mlock_nested);
ATF_TC_HEAD(mlock_nested,tc)268 ATF_TC_HEAD(mlock_nested, tc)
269 {
270 atf_tc_set_md_var(tc, "descr",
271 "Test that consecutive mlock(2) calls succeed");
272 }
273
ATF_TC_BODY(mlock_nested,tc)274 ATF_TC_BODY(mlock_nested, tc)
275 {
276 const size_t maxiter = 100;
277 void *buf;
278 int err;
279
280 buf = malloc(page);
281 ATF_REQUIRE(buf != NULL);
282 fprintf(stderr, "mlock_nested: buf = %p (page=%ld)\n", buf, page);
283
284 for (size_t i = 0; i < maxiter; i++) {
285 err = mlock(buf, page);
286 if (err != 0)
287 fprintf(stderr,
288 "mlock_nested: i=%zu (of %zu) mlock(%p, %ld): %d [%d] %s\n",
289 i, maxiter, buf, page, err, errno, strerror(errno));
290 ATF_REQUIRE(err == 0);
291 }
292
293 err = munlock(buf, page);
294 if (err != 0)
295 fprintf(stderr, "mlock_nested: munlock(%p, %ld): %d [%d] %s\n",
296 buf, page, err, errno, strerror(errno));
297 ATF_REQUIRE(err == 0);
298 free(buf);
299 }
300
ATF_TP_ADD_TCS(tp)301 ATF_TP_ADD_TCS(tp)
302 {
303
304 page = sysconf(_SC_PAGESIZE);
305 ATF_REQUIRE(page >= 0);
306
307 ATF_TP_ADD_TC(tp, mlock_clip);
308 ATF_TP_ADD_TC(tp, mlock_err);
309 ATF_TP_ADD_TC(tp, mlock_limits);
310 ATF_TP_ADD_TC(tp, mlock_mmap);
311 ATF_TP_ADD_TC(tp, mlock_nested);
312
313 return atf_no_error();
314 }
315