xref: /netbsd-src/tests/lib/libc/sys/t_mmap.c (revision e89934bbf778a6d6d6894877c4da59d0c7835b0f)
1 /* $NetBSD: t_mmap.c,v 1.12 2017/01/16 16:31:05 christos 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 1.12 2017/01/16 16:31:05 christos Exp $");
59 
60 #include <sys/param.h>
61 #include <sys/disklabel.h>
62 #include <sys/mman.h>
63 #include <sys/stat.h>
64 #include <sys/socket.h>
65 #include <sys/sysctl.h>
66 #include <sys/wait.h>
67 
68 #include <atf-c.h>
69 #include <errno.h>
70 #include <fcntl.h>
71 #include <signal.h>
72 #include <stdio.h>
73 #include <stdlib.h>
74 #include <string.h>
75 #include <unistd.h>
76 #include <paths.h>
77 
78 static long	page = 0;
79 static char	path[] = "mmap";
80 static void	map_check(void *, int);
81 static void	map_sighandler(int);
82 static void	testloan(void *, void *, char, int);
83 
84 #define	BUFSIZE	(32 * 1024)	/* enough size to trigger sosend_loan */
85 
86 static void
87 map_check(void *map, int flag)
88 {
89 
90 	if (flag != 0) {
91 		ATF_REQUIRE(map == MAP_FAILED);
92 		return;
93 	}
94 
95 	ATF_REQUIRE(map != MAP_FAILED);
96 	ATF_REQUIRE(munmap(map, page) == 0);
97 }
98 
99 void
100 testloan(void *vp, void *vp2, char pat, int docheck)
101 {
102 	char buf[BUFSIZE];
103 	char backup[BUFSIZE];
104 	ssize_t nwritten;
105 	ssize_t nread;
106 	int fds[2];
107 	int val;
108 
109 	val = BUFSIZE;
110 
111 	if (docheck != 0)
112 		(void)memcpy(backup, vp, BUFSIZE);
113 
114 	if (socketpair(AF_LOCAL, SOCK_STREAM, PF_UNSPEC, fds) != 0)
115 		atf_tc_fail("socketpair() failed");
116 
117 	val = BUFSIZE;
118 
119 	if (setsockopt(fds[1], SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)) != 0)
120 		atf_tc_fail("setsockopt() failed, SO_RCVBUF");
121 
122 	val = BUFSIZE;
123 
124 	if (setsockopt(fds[0], SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)) != 0)
125 		atf_tc_fail("setsockopt() failed, SO_SNDBUF");
126 
127 	if (fcntl(fds[0], F_SETFL, O_NONBLOCK) != 0)
128 		atf_tc_fail("fcntl() failed");
129 
130 	nwritten = write(fds[0], (char *)vp + page, BUFSIZE - page);
131 
132 	if (nwritten == -1)
133 		atf_tc_fail("write() failed");
134 
135 	/* Break loan. */
136 	(void)memset(vp2, pat, BUFSIZE);
137 
138 	nread = read(fds[1], buf + page, BUFSIZE - page);
139 
140 	if (nread == -1)
141 		atf_tc_fail("read() failed");
142 
143 	if (nread != nwritten)
144 		atf_tc_fail("too short read");
145 
146 	if (docheck != 0 && memcmp(backup, buf + page, nread) != 0)
147 		atf_tc_fail("data mismatch");
148 
149 	ATF_REQUIRE(close(fds[0]) == 0);
150 	ATF_REQUIRE(close(fds[1]) == 0);
151 }
152 
153 static void
154 map_sighandler(int signo)
155 {
156 	_exit(signo);
157 }
158 
159 ATF_TC(mmap_block);
160 ATF_TC_HEAD(mmap_block, tc)
161 {
162 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) with a block device");
163 	atf_tc_set_md_var(tc, "require.user", "root");
164 }
165 
166 ATF_TC_BODY(mmap_block, tc)
167 {
168 	static const int mib[] = { CTL_HW, HW_DISKNAMES };
169 	static const unsigned int miblen = __arraycount(mib);
170 	char *map, *dk, *drives, dev[PATH_MAX];
171 	size_t len;
172 	int fd = -1;
173 
174 	atf_tc_skip("The test case causes a panic (PR kern/38889, kern/46592)");
175 
176 	ATF_REQUIRE(sysctl(mib, miblen, NULL, &len, NULL, 0) == 0);
177 	drives = malloc(len);
178 	ATF_REQUIRE(drives != NULL);
179 	ATF_REQUIRE(sysctl(mib, miblen, drives, &len, NULL, 0) == 0);
180 	for (dk = strtok(drives, " "); dk != NULL; dk = strtok(NULL, " ")) {
181 		sprintf(dev, _PATH_DEV "%s%c", dk, 'a'+RAW_PART);
182 		fprintf(stderr, "trying: %s\n", dev);
183 
184 		if ((fd = open(dev, O_RDONLY)) >= 0) {
185 			(void)fprintf(stderr, "using %s\n", dev);
186 			break;
187 		}
188 	}
189 	free(drives);
190 
191 	if (fd < 0)
192 		atf_tc_skip("failed to find suitable block device");
193 
194 	map = mmap(NULL, 4096, PROT_READ, MAP_FILE, fd, 0);
195 	ATF_REQUIRE(map != MAP_FAILED);
196 
197 	(void)fprintf(stderr, "first byte %x\n", *map);
198 	ATF_REQUIRE(close(fd) == 0);
199 	(void)fprintf(stderr, "first byte %x\n", *map);
200 
201 	ATF_REQUIRE(munmap(map, 4096) == 0);
202 }
203 
204 ATF_TC(mmap_err);
205 ATF_TC_HEAD(mmap_err, tc)
206 {
207 	atf_tc_set_md_var(tc, "descr", "Test error conditions of mmap(2)");
208 }
209 
210 ATF_TC_BODY(mmap_err, tc)
211 {
212 	size_t addr = SIZE_MAX;
213 	void *map;
214 
215 	errno = 0;
216 	map = mmap(NULL, 3, PROT_READ, MAP_FILE|MAP_PRIVATE, -1, 0);
217 
218 	ATF_REQUIRE(map == MAP_FAILED);
219 	ATF_REQUIRE(errno == EBADF);
220 
221 	errno = 0;
222 	map = mmap(&addr, page, PROT_READ, MAP_FIXED|MAP_PRIVATE, -1, 0);
223 
224 	ATF_REQUIRE(map == MAP_FAILED);
225 	ATF_REQUIRE(errno == EINVAL);
226 
227 	errno = 0;
228 	map = mmap(NULL, page, PROT_READ, MAP_ANON|MAP_PRIVATE, INT_MAX, 0);
229 
230 	ATF_REQUIRE(map == MAP_FAILED);
231 	ATF_REQUIRE(errno == EINVAL);
232 }
233 
234 ATF_TC_WITH_CLEANUP(mmap_loan);
235 ATF_TC_HEAD(mmap_loan, tc)
236 {
237 	atf_tc_set_md_var(tc, "descr", "Test uvm page loanout with mmap(2)");
238 }
239 
240 ATF_TC_BODY(mmap_loan, tc)
241 {
242 	char buf[BUFSIZE];
243 	char *vp, *vp2;
244 	int fd;
245 
246 	fd = open(path, O_RDWR | O_CREAT, 0600);
247 	ATF_REQUIRE(fd >= 0);
248 
249 	(void)memset(buf, 'x', sizeof(buf));
250 	(void)write(fd, buf, sizeof(buf));
251 
252 	vp = mmap(NULL, BUFSIZE, PROT_READ | PROT_WRITE,
253 	    MAP_FILE | MAP_PRIVATE, fd, 0);
254 
255 	ATF_REQUIRE(vp != MAP_FAILED);
256 
257 	vp2 = vp;
258 
259 	testloan(vp, vp2, 'A', 0);
260 	testloan(vp, vp2, 'B', 1);
261 
262 	ATF_REQUIRE(munmap(vp, BUFSIZE) == 0);
263 
264 	vp = mmap(NULL, BUFSIZE, PROT_READ | PROT_WRITE,
265 	    MAP_FILE | MAP_SHARED, fd, 0);
266 
267 	vp2 = mmap(NULL, BUFSIZE, PROT_READ | PROT_WRITE,
268 	    MAP_FILE | MAP_SHARED, fd, 0);
269 
270 	ATF_REQUIRE(vp != MAP_FAILED);
271 	ATF_REQUIRE(vp2 != MAP_FAILED);
272 
273 	testloan(vp, vp2, 'E', 1);
274 
275 	ATF_REQUIRE(munmap(vp, BUFSIZE) == 0);
276 	ATF_REQUIRE(munmap(vp2, BUFSIZE) == 0);
277 }
278 
279 ATF_TC_CLEANUP(mmap_loan, tc)
280 {
281 	(void)unlink(path);
282 }
283 
284 ATF_TC_WITH_CLEANUP(mmap_prot_1);
285 ATF_TC_HEAD(mmap_prot_1, tc)
286 {
287 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) protections, #1");
288 }
289 
290 ATF_TC_BODY(mmap_prot_1, tc)
291 {
292 	void *map;
293 	int fd;
294 
295 	/*
296 	 * Open a file write-only and try to
297 	 * map it read-only. This should fail.
298 	 */
299 	fd = open(path, O_WRONLY | O_CREAT, 0700);
300 
301 	if (fd < 0)
302 		return;
303 
304 	ATF_REQUIRE(write(fd, "XXX", 3) == 3);
305 
306 	map = mmap(NULL, 3, PROT_READ, MAP_FILE|MAP_PRIVATE, fd, 0);
307 	map_check(map, 1);
308 
309 	map = mmap(NULL, 3, PROT_WRITE, MAP_FILE|MAP_PRIVATE, fd, 0);
310 	map_check(map, 0);
311 
312 	ATF_REQUIRE(close(fd) == 0);
313 }
314 
315 ATF_TC_CLEANUP(mmap_prot_1, tc)
316 {
317 	(void)unlink(path);
318 }
319 
320 ATF_TC(mmap_prot_2);
321 ATF_TC_HEAD(mmap_prot_2, tc)
322 {
323 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) protections, #2");
324 }
325 
326 ATF_TC_BODY(mmap_prot_2, tc)
327 {
328 	char buf[2];
329 	void *map;
330 	pid_t pid;
331 	int sta;
332 
333 	/*
334 	 * Make a PROT_NONE mapping and try to access it.
335 	 * If we catch a SIGSEGV, all works as expected.
336 	 */
337 	map = mmap(NULL, page, PROT_NONE, MAP_ANON|MAP_PRIVATE, -1, 0);
338 	ATF_REQUIRE(map != MAP_FAILED);
339 
340 	pid = fork();
341 	ATF_REQUIRE(pid >= 0);
342 
343 	if (pid == 0) {
344 		ATF_REQUIRE(signal(SIGSEGV, map_sighandler) != SIG_ERR);
345 		ATF_REQUIRE(strlcpy(buf, map, sizeof(buf)) != 0);
346 	}
347 
348 	(void)wait(&sta);
349 
350 	ATF_REQUIRE(WIFEXITED(sta) != 0);
351 	ATF_REQUIRE(WEXITSTATUS(sta) == SIGSEGV);
352 	ATF_REQUIRE(munmap(map, page) == 0);
353 }
354 
355 ATF_TC_WITH_CLEANUP(mmap_prot_3);
356 ATF_TC_HEAD(mmap_prot_3, tc)
357 {
358 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) protections, #3");
359 }
360 
361 ATF_TC_BODY(mmap_prot_3, tc)
362 {
363 	char buf[2];
364 	int fd, sta;
365 	void *map;
366 	pid_t pid;
367 
368 	/*
369 	 * Open a file, change the permissions
370 	 * to read-only, and try to map it as
371 	 * PROT_NONE. This should succeed, but
372 	 * the access should generate SIGSEGV.
373 	 */
374 	fd = open(path, O_RDWR | O_CREAT, 0700);
375 
376 	if (fd < 0)
377 		return;
378 
379 	ATF_REQUIRE(write(fd, "XXX", 3) == 3);
380 	ATF_REQUIRE(close(fd) == 0);
381 	ATF_REQUIRE(chmod(path, 0444) == 0);
382 
383 	fd = open(path, O_RDONLY);
384 	ATF_REQUIRE(fd != -1);
385 
386 	map = mmap(NULL, 3, PROT_NONE, MAP_FILE | MAP_SHARED, fd, 0);
387 	ATF_REQUIRE(map != MAP_FAILED);
388 
389 	pid = fork();
390 
391 	ATF_REQUIRE(pid >= 0);
392 
393 	if (pid == 0) {
394 		ATF_REQUIRE(signal(SIGSEGV, map_sighandler) != SIG_ERR);
395 		ATF_REQUIRE(strlcpy(buf, map, sizeof(buf)) != 0);
396 	}
397 
398 	(void)wait(&sta);
399 
400 	ATF_REQUIRE(WIFEXITED(sta) != 0);
401 	ATF_REQUIRE(WEXITSTATUS(sta) == SIGSEGV);
402 	ATF_REQUIRE(munmap(map, 3) == 0);
403 }
404 
405 ATF_TC_CLEANUP(mmap_prot_3, tc)
406 {
407 	(void)unlink(path);
408 }
409 
410 ATF_TC_WITH_CLEANUP(mmap_truncate);
411 ATF_TC_HEAD(mmap_truncate, tc)
412 {
413 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) and ftruncate(2)");
414 }
415 
416 ATF_TC_BODY(mmap_truncate, tc)
417 {
418 	char *map;
419 	long i;
420 	int fd;
421 
422 	fd = open(path, O_RDWR | O_CREAT, 0700);
423 
424 	if (fd < 0)
425 		return;
426 
427 	/*
428 	 * See that ftruncate(2) works
429 	 * while the file is mapped.
430 	 */
431 	ATF_REQUIRE(ftruncate(fd, page) == 0);
432 
433 	map = mmap(NULL, page, PROT_READ | PROT_WRITE, MAP_FILE|MAP_PRIVATE,
434 	     fd, 0);
435 	ATF_REQUIRE(map != MAP_FAILED);
436 
437 	for (i = 0; i < page; i++)
438 		map[i] = 'x';
439 
440 	ATF_REQUIRE(ftruncate(fd, 0) == 0);
441 	ATF_REQUIRE(ftruncate(fd, page / 8) == 0);
442 	ATF_REQUIRE(ftruncate(fd, page / 4) == 0);
443 	ATF_REQUIRE(ftruncate(fd, page / 2) == 0);
444 	ATF_REQUIRE(ftruncate(fd, page / 12) == 0);
445 	ATF_REQUIRE(ftruncate(fd, page / 64) == 0);
446 
447 	(void)munmap(map, page);
448 	ATF_REQUIRE(close(fd) == 0);
449 }
450 
451 ATF_TC_CLEANUP(mmap_truncate, tc)
452 {
453 	(void)unlink(path);
454 }
455 
456 ATF_TC_WITH_CLEANUP(mmap_truncate_signal);
457 ATF_TC_HEAD(mmap_truncate_signal, tc)
458 {
459 	atf_tc_set_md_var(tc, "descr",
460 	    "Test mmap(2) ftruncate(2) causing signal");
461 }
462 
463 ATF_TC_BODY(mmap_truncate_signal, tc)
464 {
465 	char *map;
466 	long i;
467 	int fd, sta;
468 	pid_t pid;
469 
470 	fd = open(path, O_RDWR | O_CREAT, 0700);
471 
472 	if (fd < 0)
473 		return;
474 
475 	ATF_REQUIRE(write(fd, "foo\n", 5) == 5);
476 
477 	map = mmap(NULL, page, PROT_READ, MAP_FILE|MAP_PRIVATE, fd, 0);
478 	ATF_REQUIRE(map != MAP_FAILED);
479 
480 	sta = 0;
481 	for (i = 0; i < 5; i++)
482 		sta += map[i];
483 	ATF_REQUIRE(sta == 334);
484 
485 	ATF_REQUIRE(ftruncate(fd, 0) == 0);
486 	pid = fork();
487 	ATF_REQUIRE(pid >= 0);
488 
489 	if (pid == 0) {
490 		ATF_REQUIRE(signal(SIGBUS, map_sighandler) != SIG_ERR);
491 		ATF_REQUIRE(signal(SIGSEGV, map_sighandler) != SIG_ERR);
492 		sta = 0;
493 		for (i = 0; i < page; i++)
494 			sta += map[i];
495 		/* child never will get this far, but the compiler will
496 		   not know, so better use the values calculated to
497 		   prevent the access to be optimized out */
498 		ATF_REQUIRE(i == 0);
499 		ATF_REQUIRE(sta == 0);
500 		(void)munmap(map, page);
501 		(void)close(fd);
502 		return;
503 	}
504 
505 	(void)wait(&sta);
506 
507 	ATF_REQUIRE(WIFEXITED(sta) != 0);
508 	if (WEXITSTATUS(sta) == SIGSEGV)
509 		atf_tc_fail("child process got SIGSEGV instead of SIGBUS");
510 	ATF_REQUIRE(WEXITSTATUS(sta) == SIGBUS);
511 	ATF_REQUIRE(munmap(map, page) == 0);
512 	ATF_REQUIRE(close(fd) == 0);
513 }
514 
515 ATF_TC_CLEANUP(mmap_truncate_signal, tc)
516 {
517 	(void)unlink(path);
518 }
519 
520 ATF_TC(mmap_va0);
521 ATF_TC_HEAD(mmap_va0, tc)
522 {
523 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) and vm.user_va0_disable");
524 }
525 
526 ATF_TC_BODY(mmap_va0, tc)
527 {
528 	int flags = MAP_ANON | MAP_FIXED | MAP_PRIVATE;
529 	size_t len = sizeof(int);
530 	void *map;
531 	int val;
532 
533 	/*
534 	 * Make an anonymous fixed mapping at zero address. If the address
535 	 * is restricted as noted in security(7), the syscall should fail.
536 	 */
537 	if (sysctlbyname("vm.user_va0_disable", &val, &len, NULL, 0) != 0)
538 		atf_tc_fail("failed to read vm.user_va0_disable");
539 
540 	map = mmap(NULL, page, PROT_EXEC, flags, -1, 0);
541 	map_check(map, val);
542 
543 	map = mmap(NULL, page, PROT_READ, flags, -1, 0);
544 	map_check(map, val);
545 
546 	map = mmap(NULL, page, PROT_WRITE, flags, -1, 0);
547 	map_check(map, val);
548 
549 	map = mmap(NULL, page, PROT_READ|PROT_WRITE, flags, -1, 0);
550 	map_check(map, val);
551 
552 	map = mmap(NULL, page, PROT_EXEC|PROT_READ|PROT_WRITE, flags, -1, 0);
553 	map_check(map, val);
554 }
555 
556 ATF_TP_ADD_TCS(tp)
557 {
558 	page = sysconf(_SC_PAGESIZE);
559 	ATF_REQUIRE(page >= 0);
560 
561 	ATF_TP_ADD_TC(tp, mmap_block);
562 	ATF_TP_ADD_TC(tp, mmap_err);
563 	ATF_TP_ADD_TC(tp, mmap_loan);
564 	ATF_TP_ADD_TC(tp, mmap_prot_1);
565 	ATF_TP_ADD_TC(tp, mmap_prot_2);
566 	ATF_TP_ADD_TC(tp, mmap_prot_3);
567 	ATF_TP_ADD_TC(tp, mmap_truncate);
568 	ATF_TP_ADD_TC(tp, mmap_truncate_signal);
569 	ATF_TP_ADD_TC(tp, mmap_va0);
570 
571 	return atf_no_error();
572 }
573