xref: /freebsd/tests/sys/vm/mmap_test.c (revision ca853dee3b8f26f53d48d685f32ec0b8396369e8)
1 /*-
2  * Copyright (c) 2009	Simon L. Nielsen <simon@FreeBSD.org>,
3  * 			Bjoern A. Zeeb <bz@FreeBSD.org>
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #include <sys/param.h>
30 #include <sys/mman.h>
31 #include <sys/sysctl.h>
32 
33 #include <atf-c.h>
34 #include <errno.h>
35 #include <fcntl.h>
36 #include <stdarg.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 
40 static const struct {
41 	void	*addr;
42 	int	ok[2];	/* Depending on security.bsd.map_at_zero {0, !=0}. */
43 } map_at_zero_tests[] = {
44 	{ (void *)0,			{ 0, 1 } }, /* Test sysctl. */
45 	{ (void *)1,			{ 0, 0 } },
46 	{ (void *)(PAGE_SIZE - 1),	{ 0, 0 } },
47 	{ (void *)PAGE_SIZE,		{ 1, 1 } },
48 	{ (void *)-1,			{ 0, 0 } },
49 	{ (void *)(-PAGE_SIZE),		{ 0, 0 } },
50 	{ (void *)(-1 - PAGE_SIZE),	{ 0, 0 } },
51 	{ (void *)(-1 - PAGE_SIZE - 1),	{ 0, 0 } },
52 	{ (void *)(0x1000 * PAGE_SIZE),	{ 1, 1 } },
53 };
54 
55 #define	MAP_AT_ZERO	"security.bsd.map_at_zero"
56 
57 ATF_TC_WITHOUT_HEAD(mmap__map_at_zero);
58 ATF_TC_BODY(mmap__map_at_zero, tc)
59 {
60 	void *p;
61 	size_t len;
62 	unsigned int i;
63 	int map_at_zero;
64 
65 	len = sizeof(map_at_zero);
66 	if (sysctlbyname(MAP_AT_ZERO, &map_at_zero, &len, NULL, 0) == -1) {
67 		atf_tc_skip("sysctl for %s failed: %s\n", MAP_AT_ZERO,
68 		    strerror(errno));
69 		return;
70 	}
71 
72 	/* Normalize to 0 or 1 for array access. */
73 	map_at_zero = !!map_at_zero;
74 
75 	for (i = 0; i < nitems(map_at_zero_tests); i++) {
76 		p = mmap((void *)map_at_zero_tests[i].addr, PAGE_SIZE,
77 		    PROT_READ | PROT_WRITE | PROT_EXEC, MAP_ANON | MAP_FIXED,
78 		    -1, 0);
79 		if (p == MAP_FAILED) {
80 			ATF_CHECK_MSG(map_at_zero_tests[i].ok[map_at_zero] == 0,
81 			    "mmap(%p, ...) failed", map_at_zero_tests[i].addr);
82 		} else {
83 			ATF_CHECK_MSG(map_at_zero_tests[i].ok[map_at_zero] == 1,
84 			    "mmap(%p, ...) succeeded: p=%p\n",
85 			    map_at_zero_tests[i].addr, p);
86 		}
87 	}
88 }
89 
90 static void
91 checked_mmap(int prot, int flags, int fd, int error, const char *msg)
92 {
93 	void *p;
94 	int pagesize;
95 
96 	ATF_REQUIRE((pagesize = getpagesize()) > 0);
97 	p = mmap(NULL, pagesize, prot, flags, fd, 0);
98 	if (p == MAP_FAILED) {
99 		if (error == 0)
100 			ATF_CHECK_MSG(0, "%s failed with errno %d", msg,
101 			    errno);
102 		else
103 			ATF_CHECK_EQ_MSG(error, errno,
104 			    "%s failed with wrong errno %d (expected %d)", msg,
105 			    errno, error);
106 	} else {
107 		ATF_CHECK_MSG(error == 0, "%s succeeded", msg);
108 		munmap(p, pagesize);
109 	}
110 }
111 
112 ATF_TC_WITHOUT_HEAD(mmap__bad_arguments);
113 ATF_TC_BODY(mmap__bad_arguments, tc)
114 {
115 	int devstatfd, pagesize, shmfd, zerofd;
116 
117 	ATF_REQUIRE((pagesize = getpagesize()) > 0);
118 	ATF_REQUIRE((devstatfd = open("/dev/devstat", O_RDONLY)) >= 0);
119 	ATF_REQUIRE((shmfd = shm_open(SHM_ANON, O_RDWR, 0644)) >= 0);
120 	ATF_REQUIRE(ftruncate(shmfd, pagesize) == 0);
121 	ATF_REQUIRE((zerofd = open("/dev/zero", O_RDONLY)) >= 0);
122 
123 	/* These should work. */
124 	checked_mmap(PROT_READ | PROT_WRITE, MAP_ANON, -1, 0,
125 	    "simple MAP_ANON");
126 	checked_mmap(PROT_READ | PROT_WRITE, MAP_SHARED, shmfd, 0,
127 	    "simple shm fd shared");
128 	checked_mmap(PROT_READ | PROT_WRITE, MAP_PRIVATE, shmfd, 0,
129 	    "simple shm fd private");
130 	checked_mmap(PROT_READ, MAP_SHARED, zerofd, 0,
131 	    "simple /dev/zero shared");
132 	checked_mmap(PROT_READ | PROT_WRITE, MAP_PRIVATE, zerofd, 0,
133 	    "simple /dev/zero private");
134 	checked_mmap(PROT_READ, MAP_SHARED, devstatfd, 0,
135 	    "simple /dev/devstat shared");
136 
137 	/* Extra PROT flags. */
138 	checked_mmap(PROT_READ | PROT_WRITE | 0x100000, MAP_ANON, -1, EINVAL,
139 	    "MAP_ANON with extra PROT flags");
140 	checked_mmap(0xffff, MAP_SHARED, shmfd, EINVAL,
141 	    "shm fd with garbage PROT");
142 
143 	/* Undefined flag. */
144 	checked_mmap(PROT_READ | PROT_WRITE, MAP_ANON | MAP_RESERVED0080, -1,
145 	    EINVAL, "Undefined flag");
146 
147 	/* Both MAP_SHARED and MAP_PRIVATE */
148 	checked_mmap(PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE |
149 	    MAP_SHARED, -1, EINVAL, "MAP_ANON with both SHARED and PRIVATE");
150 	checked_mmap(PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_SHARED, shmfd,
151 	    EINVAL, "shm fd with both SHARED and PRIVATE");
152 
153 	/* At least one of MAP_SHARED or MAP_PRIVATE without ANON */
154 	checked_mmap(PROT_READ | PROT_WRITE, 0, shmfd, EINVAL,
155 	    "shm fd without sharing flag");
156 
157 	/* MAP_ANON with either sharing flag (impacts fork). */
158 	checked_mmap(PROT_READ | PROT_WRITE, MAP_ANON | MAP_SHARED, -1, 0,
159 	    "shared MAP_ANON");
160 	checked_mmap(PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0,
161 	    "private MAP_ANON");
162 
163 	/* MAP_ANON should require an fd of -1. */
164 	checked_mmap(PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, 0, EINVAL,
165 	    "MAP_ANON with fd != -1");
166 
167 	/* Writable MAP_SHARED should fail on read-only descriptors. */
168 	checked_mmap(PROT_READ | PROT_WRITE, MAP_SHARED, zerofd, EACCES,
169 	    "MAP_SHARED of read-only /dev/zero");
170 
171 	/*
172 	 * Character devices other than /dev/zero do not support private
173 	 * mappings.
174 	 */
175 	checked_mmap(PROT_READ, MAP_PRIVATE, devstatfd, EINVAL,
176 	    "MAP_PRIVATE of /dev/devstat");
177 
178 	close(devstatfd);
179 	close(shmfd);
180 	close(zerofd);
181 }
182 
183 ATF_TC_WITHOUT_HEAD(mmap__dev_zero_private);
184 ATF_TC_BODY(mmap__dev_zero_private, tc)
185 {
186 	char *p1, *p2, *p3;
187 	int fd, i, pagesize;
188 
189 	ATF_REQUIRE((pagesize = getpagesize()) > 0);
190 	ATF_REQUIRE((fd = open("/dev/zero", O_RDONLY)) >= 0);
191 
192 	p1 = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
193 	ATF_REQUIRE(p1 != MAP_FAILED);
194 
195 	p2 = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
196 	ATF_REQUIRE(p2 != MAP_FAILED);
197 
198 	for (i = 0; i < pagesize; i++)
199 		ATF_REQUIRE_EQ_MSG(0, p1[i], "byte at p1[%d] is %x", i, p1[i]);
200 
201 	ATF_REQUIRE(memcmp(p1, p2, pagesize) == 0);
202 
203 	p1[0] = 1;
204 
205 	ATF_REQUIRE(p2[0] == 0);
206 
207 	p2[0] = 2;
208 
209 	ATF_REQUIRE(p1[0] == 1);
210 
211 	p3 = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
212 	ATF_REQUIRE(p3 != MAP_FAILED);
213 
214 	ATF_REQUIRE(p3[0] == 0);
215 
216 	munmap(p1, pagesize);
217 	munmap(p2, pagesize);
218 	munmap(p3, pagesize);
219 	close(fd);
220 }
221 
222 ATF_TC_WITHOUT_HEAD(mmap__dev_zero_shared);
223 ATF_TC_BODY(mmap__dev_zero_shared, tc)
224 {
225 	char *p1, *p2, *p3;
226 	int fd, i, pagesize;
227 
228 	ATF_REQUIRE((pagesize = getpagesize()) > 0);
229 	ATF_REQUIRE((fd = open("/dev/zero", O_RDWR)) >= 0);
230 
231 	p1 = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
232 	ATF_REQUIRE(p1 != MAP_FAILED);
233 
234 	p2 = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
235 	ATF_REQUIRE(p2 != MAP_FAILED);
236 
237 	for (i = 0; i < pagesize; i++)
238 		ATF_REQUIRE_EQ_MSG(0, p1[i], "byte at p1[%d] is %x", i, p1[i]);
239 
240 	ATF_REQUIRE(memcmp(p1, p2, pagesize) == 0);
241 
242 	p1[0] = 1;
243 
244 	ATF_REQUIRE(p2[0] == 0);
245 
246 	p2[0] = 2;
247 
248 	ATF_REQUIRE(p1[0] == 1);
249 
250 	p3 = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
251 	    0);
252 	ATF_REQUIRE(p3 != MAP_FAILED);
253 
254 	ATF_REQUIRE(p3[0] == 0);
255 
256 	munmap(p1, pagesize);
257 	munmap(p2, pagesize);
258 	munmap(p3, pagesize);
259 	close(fd);
260 }
261 
262 ATF_TC_WITHOUT_HEAD(mmap__write_only);
263 ATF_TC_BODY(mmap__write_only, tc)
264 {
265 	void *p;
266 	int pagesize;
267 
268 	ATF_REQUIRE((pagesize = getpagesize()) > 0);
269 	p = mmap(NULL, pagesize, PROT_WRITE, MAP_ANON, -1, 0);
270 	ATF_REQUIRE(p != MAP_FAILED);
271 
272 	*(volatile uint32_t *)p = 0x12345678;
273 
274 	munmap(p, pagesize);
275 }
276 
277 ATF_TP_ADD_TCS(tp)
278 {
279 
280 	ATF_TP_ADD_TC(tp, mmap__map_at_zero);
281 	ATF_TP_ADD_TC(tp, mmap__bad_arguments);
282 	ATF_TP_ADD_TC(tp, mmap__dev_zero_private);
283 	ATF_TP_ADD_TC(tp, mmap__dev_zero_shared);
284 	ATF_TP_ADD_TC(tp, mmap__write_only);
285 
286 	return (atf_no_error());
287 }
288