t_mlock.c revision 276478 
1/* $NetBSD: t_mlock.c,v 1.5 2014/02/26 20:49:26 martin 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 1.5 2014/02/26 20:49:26 martin Exp $");
33
34#ifdef __FreeBSD__
35#include <sys/types.h>
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#define _KMEMUSER
51#include <machine/vmparam.h>
52#endif
53
54static long page = 0;
55
56ATF_TC(mlock_clip);
57ATF_TC_HEAD(mlock_clip, tc)
58{
59	atf_tc_set_md_var(tc, "descr", "Test with mlock(2) that UVM only "
60	    "clips if the clip address is within the entry (PR kern/44788)");
61}
62
63ATF_TC_BODY(mlock_clip, tc)
64{
65	void *buf;
66
67	buf = malloc(page);
68	ATF_REQUIRE(buf != NULL);
69
70	if (page < 1024)
71		atf_tc_skip("page size too small");
72
73	for (size_t i = page; i >= 1; i = i - 1024) {
74		(void)mlock(buf, page - i);
75		(void)munlock(buf, page - i);
76	}
77
78	free(buf);
79}
80
81ATF_TC(mlock_err);
82ATF_TC_HEAD(mlock_err, tc)
83{
84	atf_tc_set_md_var(tc, "descr",
85	    "Test error conditions in mlock(2) and munlock(2)");
86}
87
88ATF_TC_BODY(mlock_err, tc)
89{
90#ifdef __NetBSD__
91	unsigned long vmin = 0;
92	size_t len = sizeof(vmin);
93#endif
94	void *invalid_ptr;
95	int null_errno = ENOMEM;	/* error expected for NULL */
96
97#ifdef __FreeBSD__
98#ifdef VM_MIN_ADDRESS
99	if ((uintptr_t)VM_MIN_ADDRESS > 0)
100		null_errno = EINVAL;	/* NULL is not inside user VM */
101#endif
102#else
103	if (sysctlbyname("vm.minaddress", &vmin, &len, NULL, 0) != 0)
104		atf_tc_fail("failed to read vm.minaddress");
105
106	if (vmin > 0)
107		null_errno = EINVAL;	/* NULL is not inside user VM */
108#endif
109
110	errno = 0;
111	ATF_REQUIRE_ERRNO(null_errno, mlock(NULL, page) == -1);
112
113	errno = 0;
114	ATF_REQUIRE_ERRNO(null_errno, mlock((char *)0, page) == -1);
115
116	errno = 0;
117	ATF_REQUIRE_ERRNO(EINVAL, mlock((char *)-1, page) == -1);
118
119	errno = 0;
120	ATF_REQUIRE_ERRNO(null_errno, munlock(NULL, page) == -1);
121
122	errno = 0;
123	ATF_REQUIRE_ERRNO(null_errno, munlock((char *)0, page) == -1);
124
125	errno = 0;
126	ATF_REQUIRE_ERRNO(EINVAL, munlock((char *)-1, page) == -1);
127
128	/*
129	 * Try to create a pointer to an unmapped page - first after current
130	 * brk will likely do.
131	 */
132	invalid_ptr = (void*)(((uintptr_t)sbrk(0)+page) & ~(page-1));
133	printf("testing with (hopefully) invalid pointer %p\n", invalid_ptr);
134
135	errno = 0;
136	ATF_REQUIRE_ERRNO(ENOMEM, mlock(invalid_ptr, page) == -1);
137
138	errno = 0;
139	ATF_REQUIRE_ERRNO(ENOMEM, munlock(invalid_ptr, page) == -1);
140}
141
142ATF_TC(mlock_limits);
143ATF_TC_HEAD(mlock_limits, tc)
144{
145	atf_tc_set_md_var(tc, "descr", "Test system limits with mlock(2)");
146}
147
148ATF_TC_BODY(mlock_limits, tc)
149{
150	struct rlimit res;
151	void *buf;
152	pid_t pid;
153	int sta;
154
155	buf = malloc(page);
156	ATF_REQUIRE(buf != NULL);
157
158	pid = fork();
159	ATF_REQUIRE(pid >= 0);
160
161	if (pid == 0) {
162
163		for (ssize_t i = page; i >= 2; i -= 100) {
164
165			res.rlim_cur = i - 1;
166			res.rlim_max = i - 1;
167
168			(void)fprintf(stderr, "trying to lock %zd bytes "
169			    "with %zu byte limit\n", i, (size_t)res.rlim_cur);
170
171			if (setrlimit(RLIMIT_MEMLOCK, &res) != 0)
172				_exit(EXIT_FAILURE);
173
174			errno = 0;
175
176#ifdef __FreeBSD__
177			/*
178			 * NetBSD doesn't conform to POSIX with ENOMEM requirement;
179			 * FreeBSD does.
180			 *
181			 * See: NetBSD PR # kern/48962 for more details.
182			 */
183			if (mlock(buf, i) != -1 || errno != ENOMEM) {
184#else
185			if (mlock(buf, i) != -1 || errno != EAGAIN) {
186#endif
187				(void)munlock(buf, i);
188				_exit(EXIT_FAILURE);
189			}
190		}
191
192		_exit(EXIT_SUCCESS);
193	}
194
195	(void)wait(&sta);
196
197	if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS)
198		atf_tc_fail("mlock(2) locked beyond system limits");
199
200	free(buf);
201}
202
203ATF_TC(mlock_mmap);
204ATF_TC_HEAD(mlock_mmap, tc)
205{
206	atf_tc_set_md_var(tc, "descr", "Test mlock(2)-mmap(2) interaction");
207}
208
209ATF_TC_BODY(mlock_mmap, tc)
210{
211#ifdef __NetBSD__
212	static const int flags = MAP_ANON | MAP_PRIVATE | MAP_WIRED;
213#else
214	static const int flags = MAP_ANON | MAP_PRIVATE;
215#endif
216	void *buf;
217
218	/*
219	 * Make a wired RW mapping and check that mlock(2)
220	 * does not fail for the (already locked) mapping.
221	 */
222	buf = mmap(NULL, page, PROT_READ | PROT_WRITE, flags, -1, 0);
223
224	ATF_REQUIRE(buf != MAP_FAILED);
225#ifdef __FreeBSD__
226	/*
227	 * The duplicate mlock call is added to ensure that the call works
228	 * as described above without MAP_WIRED support.
229	 */
230	ATF_REQUIRE(mlock(buf, page) == 0);
231#endif
232	ATF_REQUIRE(mlock(buf, page) == 0);
233	ATF_REQUIRE(munlock(buf, page) == 0);
234	ATF_REQUIRE(munmap(buf, page) == 0);
235	ATF_REQUIRE(munlock(buf, page) != 0);
236
237	/*
238	 * But it should be impossible to mlock(2) a PROT_NONE mapping.
239	 */
240	buf = mmap(NULL, page, PROT_NONE, flags, -1, 0);
241
242	ATF_REQUIRE(buf != MAP_FAILED);
243#ifdef __FreeBSD__
244	ATF_REQUIRE_ERRNO(ENOMEM, mlock(buf, page) != 0);
245#else
246	ATF_REQUIRE(mlock(buf, page) != 0);
247#endif
248	ATF_REQUIRE(munmap(buf, page) == 0);
249}
250
251ATF_TC(mlock_nested);
252ATF_TC_HEAD(mlock_nested, tc)
253{
254	atf_tc_set_md_var(tc, "descr",
255	    "Test that consecutive mlock(2) calls succeed");
256}
257
258ATF_TC_BODY(mlock_nested, tc)
259{
260	const size_t maxiter = 100;
261	void *buf;
262
263	buf = malloc(page);
264	ATF_REQUIRE(buf != NULL);
265
266	for (size_t i = 0; i < maxiter; i++)
267		ATF_REQUIRE(mlock(buf, page) == 0);
268
269	ATF_REQUIRE(munlock(buf, page) == 0);
270	free(buf);
271}
272
273ATF_TP_ADD_TCS(tp)
274{
275
276	page = sysconf(_SC_PAGESIZE);
277	ATF_REQUIRE(page >= 0);
278
279	ATF_TP_ADD_TC(tp, mlock_clip);
280	ATF_TP_ADD_TC(tp, mlock_err);
281	ATF_TP_ADD_TC(tp, mlock_limits);
282	ATF_TP_ADD_TC(tp, mlock_mmap);
283	ATF_TP_ADD_TC(tp, mlock_nested);
284
285	return atf_no_error();
286}
287