1 /* $NetBSD: t_mlock.c,v 1.6 2016/08/09 12:02:44 kre 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 1.6 2016/08/09 12:02:44 kre Exp $");
33 
34 #ifdef __FreeBSD__
35 #include <sys/param.h> /* NetBSD requires sys/param.h for sysctl(3), unlike FreeBSD */
36 #endif
37 #include <sys/mman.h>
38 #include <sys/resource.h>
39 #include <sys/sysctl.h>
40 #include <sys/wait.h>
41 
42 #include <errno.h>
43 #include <atf-c.h>
44 #include <stdint.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <unistd.h>
48 
49 #ifdef __FreeBSD__
50 #include <limits.h>
51 #define _KMEMUSER
52 #include <machine/vmparam.h>
53 
54 void set_vm_max_wired(u_long);
55 void restore_vm_max_wired(void);
56 #endif
57 
58 static long page = 0;
59 
60 ATF_TC(mlock_clip);
61 ATF_TC_HEAD(mlock_clip, tc)
62 {
63 	atf_tc_set_md_var(tc, "descr", "Test with mlock(2) that UVM only "
64 	    "clips if the clip address is within the entry (PR kern/44788)");
65 }
66 
67 ATF_TC_BODY(mlock_clip, tc)
68 {
69 	void *buf;
70 
71 	buf = malloc(page);
72 	ATF_REQUIRE(buf != NULL);
73 
74 	if (page < 1024)
75 		atf_tc_skip("page size too small");
76 
77 	for (size_t i = page; i >= 1; i = i - 1024) {
78 		(void)mlock(buf, page - i);
79 		(void)munlock(buf, page - i);
80 	}
81 
82 	free(buf);
83 }
84 
85 #ifdef __FreeBSD__
86 ATF_TC_WITH_CLEANUP(mlock_err);
87 #else
88 ATF_TC(mlock_err);
89 #endif
90 ATF_TC_HEAD(mlock_err, tc)
91 {
92 	atf_tc_set_md_var(tc, "descr",
93 	    "Test error conditions in mlock(2) and munlock(2)");
94 #ifdef __FreeBSD__
95 	atf_tc_set_md_var(tc, "require.config", "allow_sysctl_side_effects");
96 	atf_tc_set_md_var(tc, "require.user", "root");
97 #endif
98 }
99 
100 ATF_TC_BODY(mlock_err, tc)
101 {
102 #ifdef __NetBSD__
103 	unsigned long vmin = 0;
104 	size_t len = sizeof(vmin);
105 #endif
106 #if !defined(__aarch64__) && !defined(__riscv)
107 	void *invalid_ptr;
108 #endif
109 	int null_errno = ENOMEM;	/* error expected for NULL */
110 	void *buf;
111 
112 #ifdef __FreeBSD__
113 #ifdef VM_MIN_ADDRESS
114 	if ((uintptr_t)VM_MIN_ADDRESS > 0)
115 		null_errno = EINVAL;	/* NULL is not inside user VM */
116 #endif
117 	/* Set max_wired really really high to avoid EAGAIN */
118 	set_vm_max_wired(INT_MAX);
119 #else
120 	if (sysctlbyname("vm.minaddress", &vmin, &len, NULL, 0) != 0)
121 		atf_tc_fail("failed to read vm.minaddress");
122 	/*
123 	 * Any bad address must return ENOMEM (for lock & unlock)
124 	 */
125 	errno = 0;
126 	ATF_REQUIRE_ERRNO(ENOMEM, mlock(NULL, page) == -1);
127 
128 	if (vmin > 0)
129 		null_errno = EINVAL;	/* NULL is not inside user VM */
130 #endif
131 
132 	errno = 0;
133 	ATF_REQUIRE_ERRNO(ENOMEM, mlock((char *)0, page) == -1);
134 
135 	errno = 0;
136 	ATF_REQUIRE_ERRNO(ENOMEM, munlock(NULL, page) == -1);
137 
138 	errno = 0;
139 	ATF_REQUIRE_ERRNO(ENOMEM, munlock((char *)0, page) == -1);
140 
141 #ifdef __FreeBSD__
142 	/* Wrap around should return EINVAL */
143 	errno = 0;
144 	ATF_REQUIRE_ERRNO(EINVAL, mlock((char *)-1, page) == -1);
145 	errno = 0;
146 	ATF_REQUIRE_ERRNO(EINVAL, munlock((char *)-1, page) == -1);
147 #else
148 	errno = 0;
149 	ATF_REQUIRE_ERRNO(ENOMEM, mlock((char *)-1, page) == -1);
150 	errno = 0;
151 	ATF_REQUIRE_ERRNO(ENOMEM, munlock((char *)-1, page) == -1);
152 #endif
153 
154 	buf = malloc(page);	/* Get a valid address */
155 	ATF_REQUIRE(buf != NULL);
156 #ifdef __FreeBSD__
157 	errno = 0;
158 	/* Wrap around should return EINVAL */
159 	ATF_REQUIRE_ERRNO(EINVAL, mlock(buf, -page) == -1);
160 	errno = 0;
161 	ATF_REQUIRE_ERRNO(EINVAL, munlock(buf, -page) == -1);
162 #else
163 	errno = 0;
164 	ATF_REQUIRE_ERRNO(ENOMEM, mlock(buf, -page) == -1);
165 	errno = 0;
166 	ATF_REQUIRE_ERRNO(ENOMEM, munlock(buf, -page) == -1);
167 #endif
168 	(void)free(buf);
169 
170 /* There is no sbrk on AArch64 and RISC-V */
171 #if !defined(__aarch64__) && !defined(__riscv)
172 	/*
173 	 * Try to create a pointer to an unmapped page - first after current
174 	 * brk will likely do.
175 	 */
176 	invalid_ptr = (void*)(((uintptr_t)sbrk(0)+page) & ~(page-1));
177 	printf("testing with (hopefully) invalid pointer %p\n", invalid_ptr);
178 
179 	errno = 0;
180 	ATF_REQUIRE_ERRNO(ENOMEM, mlock(invalid_ptr, page) == -1);
181 
182 	errno = 0;
183 	ATF_REQUIRE_ERRNO(ENOMEM, munlock(invalid_ptr, page) == -1);
184 #endif
185 }
186 
187 #ifdef __FreeBSD__
188 ATF_TC_CLEANUP(mlock_err, tc)
189 {
190 
191 	restore_vm_max_wired();
192 }
193 #endif
194 
195 ATF_TC(mlock_limits);
196 ATF_TC_HEAD(mlock_limits, tc)
197 {
198 	atf_tc_set_md_var(tc, "descr", "Test system limits with mlock(2)");
199 }
200 
201 ATF_TC_BODY(mlock_limits, tc)
202 {
203 	struct rlimit res;
204 	void *buf;
205 	pid_t pid;
206 	int sta;
207 
208 	buf = malloc(page);
209 	ATF_REQUIRE(buf != NULL);
210 
211 	pid = fork();
212 	ATF_REQUIRE(pid >= 0);
213 
214 	if (pid == 0) {
215 
216 		for (ssize_t i = page; i >= 2; i -= 100) {
217 
218 			res.rlim_cur = i - 1;
219 			res.rlim_max = i - 1;
220 
221 			(void)fprintf(stderr, "trying to lock %zd bytes "
222 			    "with %zu byte limit\n", i, (size_t)res.rlim_cur);
223 
224 			if (setrlimit(RLIMIT_MEMLOCK, &res) != 0)
225 				_exit(EXIT_FAILURE);
226 
227 			errno = 0;
228 
229 #ifdef __FreeBSD__
230 			/*
231 			 * NetBSD doesn't conform to POSIX with ENOMEM requirement;
232 			 * FreeBSD does.
233 			 *
234 			 * See: NetBSD PR # kern/48962 for more details.
235 			 */
236 			if (mlock(buf, i) != -1 || errno != ENOMEM) {
237 #else
238 			if (mlock(buf, i) != -1 || errno != EAGAIN) {
239 #endif
240 				(void)munlock(buf, i);
241 				_exit(EXIT_FAILURE);
242 			}
243 		}
244 
245 		_exit(EXIT_SUCCESS);
246 	}
247 
248 	(void)wait(&sta);
249 
250 	if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS)
251 		atf_tc_fail("mlock(2) locked beyond system limits");
252 
253 	free(buf);
254 }
255 
256 #ifdef __FreeBSD__
257 ATF_TC_WITH_CLEANUP(mlock_mmap);
258 #else
259 ATF_TC(mlock_mmap);
260 #endif
261 ATF_TC_HEAD(mlock_mmap, tc)
262 {
263 	atf_tc_set_md_var(tc, "descr", "Test mlock(2)-mmap(2) interaction");
264 #ifdef __FreeBSD__
265 	atf_tc_set_md_var(tc, "require.config", "allow_sysctl_side_effects");
266 	atf_tc_set_md_var(tc, "require.user", "root");
267 #endif
268 }
269 
270 ATF_TC_BODY(mlock_mmap, tc)
271 {
272 #ifdef __NetBSD__
273 	static const int flags = MAP_ANON | MAP_PRIVATE | MAP_WIRED;
274 #else
275 	static const int flags = MAP_ANON | MAP_PRIVATE;
276 #endif
277 	void *buf;
278 
279 #ifdef __FreeBSD__
280 	/* Set max_wired really really high to avoid EAGAIN */
281 	set_vm_max_wired(INT_MAX);
282 #endif
283 
284 	/*
285 	 * Make a wired RW mapping and check that mlock(2)
286 	 * does not fail for the (already locked) mapping.
287 	 */
288 	buf = mmap(NULL, page, PROT_READ | PROT_WRITE, flags, -1, 0);
289 
290 	ATF_REQUIRE(buf != MAP_FAILED);
291 #ifdef __FreeBSD__
292 	/*
293 	 * The duplicate mlock call is added to ensure that the call works
294 	 * as described above without MAP_WIRED support.
295 	 */
296 	ATF_REQUIRE(mlock(buf, page) == 0);
297 #endif
298 	ATF_REQUIRE(mlock(buf, page) == 0);
299 	ATF_REQUIRE(munlock(buf, page) == 0);
300 	ATF_REQUIRE(munmap(buf, page) == 0);
301 	ATF_REQUIRE(munlock(buf, page) != 0);
302 
303 	/*
304 	 * But it should be impossible to mlock(2) a PROT_NONE mapping.
305 	 */
306 	buf = mmap(NULL, page, PROT_NONE, flags, -1, 0);
307 
308 	ATF_REQUIRE(buf != MAP_FAILED);
309 #ifdef __FreeBSD__
310 	ATF_REQUIRE_ERRNO(ENOMEM, mlock(buf, page) != 0);
311 #else
312 	ATF_REQUIRE(mlock(buf, page) != 0);
313 #endif
314 	ATF_REQUIRE(munmap(buf, page) == 0);
315 }
316 
317 #ifdef __FreeBSD__
318 ATF_TC_CLEANUP(mlock_mmap, tc)
319 {
320 
321 	restore_vm_max_wired();
322 }
323 #endif
324 
325 #ifdef __FreeBSD__
326 ATF_TC_WITH_CLEANUP(mlock_nested);
327 #else
328 ATF_TC(mlock_nested);
329 #endif
330 ATF_TC_HEAD(mlock_nested, tc)
331 {
332 	atf_tc_set_md_var(tc, "descr",
333 	    "Test that consecutive mlock(2) calls succeed");
334 #ifdef __FreeBSD__
335 	atf_tc_set_md_var(tc, "require.config", "allow_sysctl_side_effects");
336 	atf_tc_set_md_var(tc, "require.user", "root");
337 #endif
338 }
339 
340 ATF_TC_BODY(mlock_nested, tc)
341 {
342 	const size_t maxiter = 100;
343 	void *buf;
344 
345 #ifdef __FreeBSD__
346 	/* Set max_wired really really high to avoid EAGAIN */
347 	set_vm_max_wired(INT_MAX);
348 #endif
349 
350 	buf = malloc(page);
351 	ATF_REQUIRE(buf != NULL);
352 
353 	for (size_t i = 0; i < maxiter; i++)
354 		ATF_REQUIRE(mlock(buf, page) == 0);
355 
356 	ATF_REQUIRE(munlock(buf, page) == 0);
357 	free(buf);
358 }
359 
360 #ifdef __FreeBSD__
361 ATF_TC_CLEANUP(mlock_nested, tc)
362 {
363 
364 	restore_vm_max_wired();
365 }
366 #endif
367 
368 #ifdef __FreeBSD__
369 ATF_TC_WITH_CLEANUP(mlock_unaligned);
370 #else
371 ATF_TC(mlock_unaligned);
372 #endif
373 ATF_TC_HEAD(mlock_unaligned, tc)
374 {
375 	atf_tc_set_md_var(tc, "descr",
376 	    "Test that mlock(2) can lock page-unaligned memory");
377 #ifdef __FreeBSD__
378 	atf_tc_set_md_var(tc, "require.config", "allow_sysctl_side_effects");
379 	atf_tc_set_md_var(tc, "require.user", "root");
380 #endif
381 }
382 
383 ATF_TC_BODY(mlock_unaligned, tc)
384 {
385 	void *buf, *addr;
386 
387 #ifdef __FreeBSD__
388 	/* Set max_wired really really high to avoid EAGAIN */
389 	set_vm_max_wired(INT_MAX);
390 #endif
391 
392 	buf = malloc(page);
393 	ATF_REQUIRE(buf != NULL);
394 
395 	if ((uintptr_t)buf & ((uintptr_t)page - 1))
396 		addr = buf;
397 	else
398 		addr = (void *)(((uintptr_t)buf) + page/3);
399 
400 	ATF_REQUIRE_EQ(mlock(addr, page/5), 0);
401 	ATF_REQUIRE_EQ(munlock(addr, page/5), 0);
402 
403 	(void)free(buf);
404 }
405 
406 #ifdef __FreeBSD__
407 ATF_TC_CLEANUP(mlock_unaligned, tc)
408 {
409 
410 	restore_vm_max_wired();
411 }
412 #endif
413 
414 ATF_TC(munlock_unlocked);
415 ATF_TC_HEAD(munlock_unlocked, tc)
416 {
417 	atf_tc_set_md_var(tc, "descr",
418 #ifdef __FreeBSD__
419 	    "munlock(2) accepts unlocked memory");
420 #else
421 	    "munlock(2) of unlocked memory is an error");
422 #endif
423 	atf_tc_set_md_var(tc, "require.user", "root");
424 }
425 
426 ATF_TC_BODY(munlock_unlocked, tc)
427 {
428 	void *buf;
429 
430 	buf = malloc(page);
431 	ATF_REQUIRE(buf != NULL);
432 
433 #ifdef __FreeBSD__
434 	ATF_REQUIRE_EQ(munlock(buf, page), 0);
435 #else
436 	errno = 0;
437 	ATF_REQUIRE_ERRNO(ENOMEM, munlock(buf, page) == -1);
438 #endif
439 	(void)free(buf);
440 }
441 
442 ATF_TP_ADD_TCS(tp)
443 {
444 
445 	page = sysconf(_SC_PAGESIZE);
446 	ATF_REQUIRE(page >= 0);
447 
448 	ATF_TP_ADD_TC(tp, mlock_clip);
449 	ATF_TP_ADD_TC(tp, mlock_err);
450 	ATF_TP_ADD_TC(tp, mlock_limits);
451 	ATF_TP_ADD_TC(tp, mlock_mmap);
452 	ATF_TP_ADD_TC(tp, mlock_nested);
453 	ATF_TP_ADD_TC(tp, mlock_unaligned);
454 	ATF_TP_ADD_TC(tp, munlock_unlocked);
455 
456 	return atf_no_error();
457 }
458