xref: /netbsd-src/tests/lib/libc/sys/t_mmap.c (revision e39ef1d61eee3ccba837ee281f1e098c864487aa)
1 /* $NetBSD: t_mmap.c,v 1.2 2011/07/14 11:08:45 jruoho Exp $ */
2 
3 /*-
4  * Copyright (c) 2011 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 
32 /*-
33  * Copyright (c)2004 YAMAMOTO Takashi,
34  * All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  *
45  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
48  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
55  * SUCH DAMAGE.
56  */
57 #include <sys/cdefs.h>
58 __RCSID("$NetBSD: t_mmap.c,v 1.2 2011/07/14 11:08:45 jruoho Exp $");
59 
60 #include <sys/param.h>
61 #include <sys/mman.h>
62 #include <sys/socket.h>
63 #include <sys/sysctl.h>
64 #include <sys/wait.h>
65 
66 #include <atf-c.h>
67 #include <errno.h>
68 #include <fcntl.h>
69 #include <signal.h>
70 #include <stdlib.h>
71 #include <string.h>
72 #include <unistd.h>
73 
74 static long	page = 0;
75 static char	path[] = "mmap";
76 static void	map_check(void *, int);
77 static void	map_sighandler(int);
78 static void	testloan(void *, void *, char, int);
79 
80 #define	BUFSIZE	(32 * 1024)	/* enough size to trigger sosend_loan */
81 
82 static void
83 map_check(void *map, int flag)
84 {
85 
86 	if (flag != 0) {
87 		ATF_REQUIRE(map == MAP_FAILED);
88 		return;
89 	}
90 
91 	ATF_REQUIRE(map != MAP_FAILED);
92 	ATF_REQUIRE(munmap(map, page) == 0);
93 }
94 
95 void
96 testloan(void *vp, void *vp2, char pat, int docheck)
97 {
98 	char buf[BUFSIZE];
99 	char backup[BUFSIZE];
100 	ssize_t nwritten;
101 	ssize_t nread;
102 	int fds[2];
103 	int val;
104 
105 	val = BUFSIZE;
106 
107 	if (docheck != 0)
108 		(void)memcpy(backup, vp, BUFSIZE);
109 
110 	if (socketpair(AF_LOCAL, SOCK_STREAM, PF_UNSPEC, fds) != 0)
111 		atf_tc_fail("socketpair() failed");
112 
113 	val = BUFSIZE;
114 
115 	if (setsockopt(fds[1], SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)) != 0)
116 		atf_tc_fail("setsockopt() failed, SO_RCVBUF");
117 
118 	val = BUFSIZE;
119 
120 	if (setsockopt(fds[0], SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)) != 0)
121 		atf_tc_fail("setsockopt() failed, SO_SNDBUF");
122 
123 	if (fcntl(fds[0], F_SETFL, O_NONBLOCK) != 0)
124 		atf_tc_fail("fcntl() failed");
125 
126 	nwritten = write(fds[0], (char *)vp + page, BUFSIZE - page);
127 
128 	if (nwritten == -1)
129 		atf_tc_fail("write() failed");
130 
131 	/* Break loan. */
132 	(void)memset(vp2, pat, BUFSIZE);
133 
134 	nread = read(fds[1], buf + page, BUFSIZE - page);
135 
136 	if (nread == -1)
137 		atf_tc_fail("read() failed");
138 
139 	if (nread != nwritten)
140 		atf_tc_fail("too short read");
141 
142 	if (docheck != 0 && memcmp(backup, buf + page, nread) != 0)
143 		atf_tc_fail("data mismatch");
144 
145 	ATF_REQUIRE(close(fds[0]) == 0);
146 	ATF_REQUIRE(close(fds[1]) == 0);
147 }
148 
149 static void
150 map_sighandler(int signo)
151 {
152 	_exit(signo);
153 }
154 
155 ATF_TC(mmap_err);
156 ATF_TC_HEAD(mmap_err, tc)
157 {
158 	atf_tc_set_md_var(tc, "descr", "Test error conditions of mmap(2)");
159 }
160 
161 ATF_TC_BODY(mmap_err, tc)
162 {
163 	size_t addr = SIZE_MAX;
164 	void *map;
165 
166 	errno = 0;
167 	map = mmap(NULL, 3, PROT_READ, MAP_FILE|MAP_PRIVATE, -1, 0);
168 
169 	ATF_REQUIRE(map == MAP_FAILED);
170 	ATF_REQUIRE(errno == EBADF);
171 
172 	errno = 0;
173 	map = mmap(&addr, page, PROT_READ, MAP_FIXED|MAP_PRIVATE, -1, 0);
174 
175 	ATF_REQUIRE(map == MAP_FAILED);
176 	ATF_REQUIRE(errno == EINVAL);
177 
178 	errno = 0;
179 	map = mmap(NULL, page, PROT_READ, MAP_ANON|MAP_PRIVATE, INT_MAX, 0);
180 
181 	ATF_REQUIRE(map == MAP_FAILED);
182 	ATF_REQUIRE(errno == EINVAL);
183 }
184 
185 ATF_TC_WITH_CLEANUP(mmap_loan);
186 ATF_TC_HEAD(mmap_loan, tc)
187 {
188 	atf_tc_set_md_var(tc, "descr", "Test uvm page loanout with mmap(2)");
189 }
190 
191 ATF_TC_BODY(mmap_loan, tc)
192 {
193 	char buf[BUFSIZE];
194 	char *vp, *vp2;
195 	int fd;
196 
197 	fd = open(path, O_RDWR | O_CREAT, 0600);
198 	ATF_REQUIRE(fd >= 0);
199 
200 	(void)memset(buf, 'x', sizeof(buf));
201 	(void)write(fd, buf, sizeof(buf));
202 
203 	vp = mmap(NULL, BUFSIZE, PROT_READ | PROT_WRITE,
204 	    MAP_FILE | MAP_PRIVATE, fd, 0);
205 
206 	ATF_REQUIRE(vp != MAP_FAILED);
207 
208 	vp2 = vp;
209 
210 	testloan(vp, vp2, 'A', 0);
211 	testloan(vp, vp2, 'B', 1);
212 
213 	ATF_REQUIRE(munmap(vp, BUFSIZE) == 0);
214 
215 	vp = mmap(NULL, BUFSIZE, PROT_READ | PROT_WRITE,
216 	    MAP_FILE | MAP_SHARED, fd, 0);
217 
218 	vp2 = mmap(NULL, BUFSIZE, PROT_READ | PROT_WRITE,
219 	    MAP_FILE | MAP_SHARED, fd, 0);
220 
221 	ATF_REQUIRE(vp != MAP_FAILED);
222 	ATF_REQUIRE(vp2 != MAP_FAILED);
223 
224 	testloan(vp, vp2, 'E', 1);
225 
226 	ATF_REQUIRE(munmap(vp, BUFSIZE) == 0);
227 	ATF_REQUIRE(munmap(vp2, BUFSIZE) == 0);
228 }
229 
230 ATF_TC_CLEANUP(mmap_loan, tc)
231 {
232 	(void)unlink(path);
233 }
234 
235 ATF_TC_WITH_CLEANUP(mmap_prot_1);
236 ATF_TC_HEAD(mmap_prot_1, tc)
237 {
238 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) protections, #1");
239 }
240 
241 ATF_TC_BODY(mmap_prot_1, tc)
242 {
243 	void *map;
244 	int fd;
245 
246 	/*
247 	 * Open a file write-only and try to
248 	 * map it read-only. This should fail.
249 	 */
250 	fd = open(path, O_WRONLY | O_CREAT, 0700);
251 
252 	if (fd < 0)
253 		return;
254 
255 	ATF_REQUIRE(write(fd, "XXX", 3) == 3);
256 
257 	map = mmap(NULL, 3, PROT_READ, MAP_FILE|MAP_PRIVATE, fd, 0);
258 	map_check(map, 1);
259 
260 	map = mmap(NULL, 3, PROT_WRITE, MAP_FILE|MAP_PRIVATE, fd, 0);
261 	map_check(map, 0);
262 
263 	ATF_REQUIRE(close(fd) == 0);
264 }
265 
266 ATF_TC_CLEANUP(mmap_prot_1, tc)
267 {
268 	(void)unlink(path);
269 }
270 
271 ATF_TC(mmap_prot_2);
272 ATF_TC_HEAD(mmap_prot_2, tc)
273 {
274 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) protections, #2");
275 }
276 
277 ATF_TC_BODY(mmap_prot_2, tc)
278 {
279 	char buf[2];
280 	void *map;
281 	pid_t pid;
282 	int sta;
283 
284 	/*
285 	 * Make a PROT_NONE mapping and try to access it.
286 	 * If we catch a SIGSEGV, all works as expected.
287 	 */
288 	map = mmap(NULL, page, PROT_NONE, MAP_ANON|MAP_PRIVATE, -1, 0);
289 	ATF_REQUIRE(map != MAP_FAILED);
290 
291 	pid = fork();
292 	ATF_REQUIRE(pid >= 0);
293 
294 	if (pid == 0) {
295 		ATF_REQUIRE(signal(SIGSEGV, map_sighandler) != SIG_ERR);
296 		ATF_REQUIRE(strlcpy(buf, map, sizeof(buf)) != 0);
297 	}
298 
299 	(void)wait(&sta);
300 
301 	ATF_REQUIRE(WIFEXITED(sta) != 0);
302 	ATF_REQUIRE(WEXITSTATUS(sta) == SIGSEGV);
303 	ATF_REQUIRE(munmap(map, page) == 0);
304 }
305 
306 ATF_TC_WITH_CLEANUP(mmap_prot_3);
307 ATF_TC_HEAD(mmap_prot_3, tc)
308 {
309 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) protections, #3");
310 }
311 
312 ATF_TC_BODY(mmap_prot_3, tc)
313 {
314 	char buf[2];
315 	int fd, sta;
316 	void *map;
317 	pid_t pid;
318 
319 	/*
320 	 * Open a file, change the permissions
321 	 * to read-only, and try to map it as
322 	 * PROT_NONE. This should succeed, but
323 	 * the access should generate SIGSEGV.
324 	 */
325 	fd = open(path, O_RDWR | O_CREAT, 0700);
326 
327 	if (fd < 0)
328 		return;
329 
330 	ATF_REQUIRE(write(fd, "XXX", 3) == 3);
331 	ATF_REQUIRE(close(fd) == 0);
332 	ATF_REQUIRE(chmod(path, 0444) == 0);
333 
334 	fd = open(path, O_RDONLY);
335 	ATF_REQUIRE(fd != -1);
336 
337 	map = mmap(NULL, 3, PROT_NONE, MAP_FILE | MAP_SHARED, fd, 0);
338 	ATF_REQUIRE(map != MAP_FAILED);
339 
340 	pid = fork();
341 
342 	ATF_REQUIRE(pid >= 0);
343 
344 	if (pid == 0) {
345 		ATF_REQUIRE(signal(SIGSEGV, map_sighandler) != SIG_ERR);
346 		ATF_REQUIRE(strlcpy(buf, map, sizeof(buf)) != 0);
347 	}
348 
349 	(void)wait(&sta);
350 
351 	ATF_REQUIRE(WIFEXITED(sta) != 0);
352 	ATF_REQUIRE(WEXITSTATUS(sta) == SIGSEGV);
353 	ATF_REQUIRE(munmap(map, 3) == 0);
354 }
355 
356 ATF_TC_CLEANUP(mmap_prot_3, tc)
357 {
358 	(void)unlink(path);
359 }
360 
361 ATF_TC_WITH_CLEANUP(mmap_truncate);
362 ATF_TC_HEAD(mmap_truncate, tc)
363 {
364 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) and ftruncate(2)");
365 }
366 
367 ATF_TC_BODY(mmap_truncate, tc)
368 {
369 	char *map;
370 	long i;
371 	int fd;
372 
373 	fd = open(path, O_RDWR | O_CREAT, 0700);
374 
375 	if (fd < 0)
376 		return;
377 
378 	/*
379 	 * See that ftruncate(2) works
380 	 * while the file is mapped.
381 	 */
382 	ATF_REQUIRE(ftruncate(fd, page) == 0);
383 
384 	map = mmap(NULL, page, PROT_READ | PROT_WRITE, MAP_FILE|MAP_PRIVATE,
385 	     fd, 0);
386 	ATF_REQUIRE(map != MAP_FAILED);
387 
388 	for (i = 0; i < page; i++)
389 		map[i] = 'x';
390 
391 	ATF_REQUIRE(ftruncate(fd, 0) == 0);
392 	ATF_REQUIRE(ftruncate(fd, page / 8) == 0);
393 	ATF_REQUIRE(ftruncate(fd, page / 4) == 0);
394 	ATF_REQUIRE(ftruncate(fd, page / 2) == 0);
395 	ATF_REQUIRE(ftruncate(fd, page / 12) == 0);
396 	ATF_REQUIRE(ftruncate(fd, page / 64) == 0);
397 
398 	ATF_REQUIRE(close(fd) == 0);
399 }
400 
401 ATF_TC_CLEANUP(mmap_truncate, tc)
402 {
403 	(void)unlink(path);
404 }
405 
406 ATF_TC(mmap_va0);
407 ATF_TC_HEAD(mmap_va0, tc)
408 {
409 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) and vm.user_va0_disable");
410 }
411 
412 ATF_TC_BODY(mmap_va0, tc)
413 {
414 	int flags = MAP_ANON | MAP_FIXED | MAP_PRIVATE;
415 	size_t len = sizeof(int);
416 	void *map;
417 	int val;
418 
419 	/*
420 	 * Make an anonymous fixed mapping at zero address. If the address
421 	 * is restricted as noted in security(7), the syscall should fail.
422 	 */
423 	if (sysctlbyname("vm.user_va0_disable", &val, &len, NULL, 0) != 0)
424 		atf_tc_fail("failed to read vm.user_va0_disable");
425 
426 	map = mmap(NULL, page, PROT_EXEC, flags, -1, 0);
427 	map_check(map, val);
428 
429 	map = mmap(NULL, page, PROT_READ, flags, -1, 0);
430 	map_check(map, val);
431 
432 	map = mmap(NULL, page, PROT_WRITE, flags, -1, 0);
433 	map_check(map, val);
434 
435 	map = mmap(NULL, page, PROT_READ|PROT_WRITE, flags, -1, 0);
436 	map_check(map, val);
437 
438 	map = mmap(NULL, page, PROT_EXEC|PROT_READ|PROT_WRITE, flags, -1, 0);
439 	map_check(map, val);
440 }
441 
442 ATF_TP_ADD_TCS(tp)
443 {
444 	page = sysconf(_SC_PAGESIZE);
445 	ATF_REQUIRE(page >= 0);
446 
447 	ATF_TP_ADD_TC(tp, mmap_err);
448 	ATF_TP_ADD_TC(tp, mmap_loan);
449 	ATF_TP_ADD_TC(tp, mmap_prot_1);
450 	ATF_TP_ADD_TC(tp, mmap_prot_2);
451 	ATF_TP_ADD_TC(tp, mmap_prot_3);
452 	ATF_TP_ADD_TC(tp, mmap_truncate);
453 	ATF_TP_ADD_TC(tp, mmap_va0);
454 
455 	return atf_no_error();
456 }
457