xref: /openbsd-src/regress/lib/libc/sys/t_mmap.c (revision 15572fcf8c6bfa0588565cd23f393a5a1499ea57)
1 /*	$OpenBSD: t_mmap.c,v 1.2 2020/11/09 23:18:51 bluhm Exp $	*/
2 /* $NetBSD: t_mmap.c,v 1.14 2020/06/26 07:50:11 jruoho Exp $ */
3 
4 /*-
5  * Copyright (c) 2011 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Jukka Ruohonen.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*-
34  * Copyright (c)2004 YAMAMOTO Takashi,
35  * All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  *
46  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56  * SUCH DAMAGE.
57  */
58 
59 #include "macros.h"
60 
61 #include <sys/cdefs.h>
62 __RCSID("$NetBSD: t_mmap.c,v 1.14 2020/06/26 07:50:11 jruoho Exp $");
63 
64 #include <sys/param.h>
65 #include <sys/disklabel.h>
66 #include <sys/mman.h>
67 #include <sys/stat.h>
68 #include <sys/socket.h>
69 #include <sys/sysctl.h>
70 #include <sys/wait.h>
71 
72 #include "atf-c.h"
73 #include <errno.h>
74 #include <fcntl.h>
75 #include <signal.h>
76 #include <stdio.h>
77 #include <stdlib.h>
78 #include <string.h>
79 #include <unistd.h>
80 #include <paths.h>
81 
82 static long	page = 0;
83 static char	path[] = "mmap";
84 static void	map_check(void *, int);
85 static void	map_sighandler(int);
86 static void	testloan(void *, void *, char, int);
87 
88 #define	BUFSIZE	(32 * 1024)	/* enough size to trigger sosend_loan */
89 
90 static void
91 map_check(void *map, int flag)
92 {
93 
94 	if (flag != 0) {
95 		ATF_REQUIRE(map == MAP_FAILED);
96 		return;
97 	}
98 
99 	ATF_REQUIRE(map != MAP_FAILED);
100 	ATF_REQUIRE(munmap(map, page) == 0);
101 }
102 
103 void
104 testloan(void *vp, void *vp2, char pat, int docheck)
105 {
106 	char buf[BUFSIZE];
107 	char backup[BUFSIZE];
108 	ssize_t nwritten;
109 	ssize_t nread;
110 	int fds[2];
111 	int val;
112 
113 	val = BUFSIZE;
114 
115 	if (docheck != 0)
116 		(void)memcpy(backup, vp, BUFSIZE);
117 
118 	if (socketpair(AF_LOCAL, SOCK_STREAM, PF_UNSPEC, fds) != 0)
119 		atf_tc_fail("socketpair() failed");
120 
121 	val = BUFSIZE;
122 
123 	if (setsockopt(fds[1], SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)) != 0)
124 		atf_tc_fail("setsockopt() failed, SO_RCVBUF");
125 
126 	val = BUFSIZE;
127 
128 	if (setsockopt(fds[0], SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)) != 0)
129 		atf_tc_fail("setsockopt() failed, SO_SNDBUF");
130 
131 	if (fcntl(fds[0], F_SETFL, O_NONBLOCK) != 0)
132 		atf_tc_fail("fcntl() failed");
133 
134 	nwritten = write(fds[0], (char *)vp + page, BUFSIZE - page);
135 
136 	if (nwritten == -1)
137 		atf_tc_fail("write() failed");
138 
139 	/* Break loan. */
140 	(void)memset(vp2, pat, BUFSIZE);
141 
142 	nread = read(fds[1], buf + page, BUFSIZE - page);
143 
144 	if (nread == -1)
145 		atf_tc_fail("read() failed");
146 
147 	if (nread != nwritten)
148 		atf_tc_fail("too short read");
149 
150 	if (docheck != 0 && memcmp(backup, buf + page, nread) != 0)
151 		atf_tc_fail("data mismatch");
152 
153 	ATF_REQUIRE(close(fds[0]) == 0);
154 	ATF_REQUIRE(close(fds[1]) == 0);
155 }
156 
157 static void
158 map_sighandler(int signo)
159 {
160 	_exit(signo);
161 }
162 
163 ATF_TC(mmap_block);
164 ATF_TC_HEAD(mmap_block, tc)
165 {
166 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) with a block device");
167 	atf_tc_set_md_var(tc, "require.user", "root");
168 }
169 
170 ATF_TC_BODY(mmap_block, tc)
171 {
172 	static const int mib[] = { CTL_HW, HW_DISKNAMES };
173 	static const unsigned int miblen = __arraycount(mib);
174 	char *map, *dk, *drives, dev[PATH_MAX];
175 	size_t len;
176 	int fd = -1;
177 
178 	atf_tc_skip("The test case causes a panic " \
179 	    "(PR kern/38889, PR kern/46592)");
180 
181 	ATF_REQUIRE(sysctl(mib, miblen, NULL, &len, NULL, 0) == 0);
182 	drives = malloc(len);
183 	ATF_REQUIRE(drives != NULL);
184 	ATF_REQUIRE(sysctl(mib, miblen, drives, &len, NULL, 0) == 0);
185 	for (dk = strtok(drives, " "); dk != NULL; dk = strtok(NULL, " ")) {
186 		if (strncmp(dk, "dk", 2) == 0)
187 			snprintf(dev, sizeof(dev), _PATH_DEV "%s", dk);
188 		else
189 			snprintf(dev, sizeof(dev), _PATH_DEV "%s%c", dk,
190 			    'a' + RAW_PART);
191 		fprintf(stderr, "trying: %s\n", dev);
192 
193 		if ((fd = open(dev, O_RDONLY)) >= 0) {
194 			(void)fprintf(stderr, "using %s\n", dev);
195 			break;
196 		} else
197 			(void)fprintf(stderr, "%s: %s\n", dev, strerror(errno));
198 	}
199 	free(drives);
200 
201 	if (fd < 0)
202 		atf_tc_skip("failed to find suitable block device");
203 
204 	map = mmap(NULL, 4096, PROT_READ, MAP_FILE, fd, 0);
205 	ATF_REQUIRE_MSG(map != MAP_FAILED, "mmap: %s", strerror(errno));
206 
207 	(void)fprintf(stderr, "first byte %x\n", *map);
208 	ATF_REQUIRE(close(fd) == 0);
209 	(void)fprintf(stderr, "first byte %x\n", *map);
210 
211 	ATF_REQUIRE(munmap(map, 4096) == 0);
212 }
213 
214 ATF_TC(mmap_err);
215 ATF_TC_HEAD(mmap_err, tc)
216 {
217 	atf_tc_set_md_var(tc, "descr", "Test error conditions of mmap(2)");
218 }
219 
220 ATF_TC_BODY(mmap_err, tc)
221 {
222 	size_t addr = SIZE_MAX;
223 	void *map;
224 
225 	errno = 0;
226 	map = mmap(NULL, 3, PROT_READ, MAP_FILE|MAP_PRIVATE, -1, 0);
227 
228 	ATF_REQUIRE(map == MAP_FAILED);
229 	ATF_REQUIRE(errno == EBADF);
230 
231 	errno = 0;
232 	map = mmap(&addr, page, PROT_READ, MAP_FIXED|MAP_PRIVATE, -1, 0);
233 
234 	ATF_REQUIRE(map == MAP_FAILED);
235 	ATF_REQUIRE(errno == EINVAL);
236 
237 	errno = 0;
238 	map = mmap(NULL, page, PROT_READ, MAP_ANON|MAP_PRIVATE, INT_MAX, 0);
239 
240 	ATF_REQUIRE(map == MAP_FAILED);
241 	ATF_REQUIRE(errno == EINVAL);
242 }
243 
244 ATF_TC_WITH_CLEANUP(mmap_loan);
245 ATF_TC_HEAD(mmap_loan, tc)
246 {
247 	atf_tc_set_md_var(tc, "descr", "Test uvm page loanout with mmap(2)");
248 }
249 
250 ATF_TC_BODY(mmap_loan, tc)
251 {
252 	char buf[BUFSIZE];
253 	char *vp, *vp2;
254 	int fd;
255 
256 	fd = open(path, O_RDWR | O_CREAT, 0600);
257 	ATF_REQUIRE(fd >= 0);
258 
259 	(void)memset(buf, 'x', sizeof(buf));
260 	(void)write(fd, buf, sizeof(buf));
261 
262 	vp = mmap(NULL, BUFSIZE, PROT_READ | PROT_WRITE,
263 	    MAP_FILE | MAP_PRIVATE, fd, 0);
264 
265 	ATF_REQUIRE(vp != MAP_FAILED);
266 
267 	vp2 = vp;
268 
269 	testloan(vp, vp2, 'A', 0);
270 	testloan(vp, vp2, 'B', 1);
271 
272 	ATF_REQUIRE(munmap(vp, BUFSIZE) == 0);
273 
274 	vp = mmap(NULL, BUFSIZE, PROT_READ | PROT_WRITE,
275 	    MAP_FILE | MAP_SHARED, fd, 0);
276 
277 	vp2 = mmap(NULL, BUFSIZE, PROT_READ | PROT_WRITE,
278 	    MAP_FILE | MAP_SHARED, fd, 0);
279 
280 	ATF_REQUIRE(vp != MAP_FAILED);
281 	ATF_REQUIRE(vp2 != MAP_FAILED);
282 
283 	testloan(vp, vp2, 'E', 1);
284 
285 	ATF_REQUIRE(munmap(vp, BUFSIZE) == 0);
286 	ATF_REQUIRE(munmap(vp2, BUFSIZE) == 0);
287 }
288 
289 ATF_TC_CLEANUP(mmap_loan, tc)
290 {
291 	(void)unlink(path);
292 }
293 
294 ATF_TC_WITH_CLEANUP(mmap_prot_1);
295 ATF_TC_HEAD(mmap_prot_1, tc)
296 {
297 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) protections, #1");
298 }
299 
300 ATF_TC_BODY(mmap_prot_1, tc)
301 {
302 	void *map;
303 	int fd;
304 
305 	/*
306 	 * Open a file write-only and try to
307 	 * map it read-only. This should fail.
308 	 */
309 	fd = open(path, O_WRONLY | O_CREAT, 0700);
310 
311 	if (fd < 0)
312 		return;
313 
314 	ATF_REQUIRE(write(fd, "XXX", 3) == 3);
315 
316 	map = mmap(NULL, 3, PROT_READ, MAP_FILE|MAP_PRIVATE, fd, 0);
317 	map_check(map, 1);
318 
319 	map = mmap(NULL, 3, PROT_WRITE, MAP_FILE|MAP_PRIVATE, fd, 0);
320 	map_check(map, 0);
321 
322 	ATF_REQUIRE(close(fd) == 0);
323 }
324 
325 ATF_TC_CLEANUP(mmap_prot_1, tc)
326 {
327 	(void)unlink(path);
328 }
329 
330 ATF_TC(mmap_prot_2);
331 ATF_TC_HEAD(mmap_prot_2, tc)
332 {
333 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) protections, #2");
334 }
335 
336 ATF_TC_BODY(mmap_prot_2, tc)
337 {
338 	char buf[2];
339 	void *map;
340 	pid_t pid;
341 	int sta;
342 
343 	/*
344 	 * Make a PROT_NONE mapping and try to access it.
345 	 * If we catch a SIGSEGV, all works as expected.
346 	 */
347 	map = mmap(NULL, page, PROT_NONE, MAP_ANON|MAP_PRIVATE, -1, 0);
348 	ATF_REQUIRE(map != MAP_FAILED);
349 
350 	pid = fork();
351 	ATF_REQUIRE(pid >= 0);
352 
353 	if (pid == 0) {
354 		ATF_REQUIRE(signal(SIGSEGV, map_sighandler) != SIG_ERR);
355 		ATF_REQUIRE(strlcpy(buf, map, sizeof(buf)) != 0);
356 	}
357 
358 	(void)wait(&sta);
359 
360 	ATF_REQUIRE(WIFEXITED(sta) != 0);
361 	ATF_REQUIRE(WEXITSTATUS(sta) == SIGSEGV);
362 	ATF_REQUIRE(munmap(map, page) == 0);
363 }
364 
365 ATF_TC_WITH_CLEANUP(mmap_prot_3);
366 ATF_TC_HEAD(mmap_prot_3, tc)
367 {
368 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) protections, #3");
369 }
370 
371 ATF_TC_BODY(mmap_prot_3, tc)
372 {
373 	char buf[2];
374 	int fd, sta;
375 	void *map;
376 	pid_t pid;
377 
378 	/*
379 	 * Open a file, change the permissions
380 	 * to read-only, and try to map it as
381 	 * PROT_NONE. This should succeed, but
382 	 * the access should generate SIGSEGV.
383 	 */
384 	fd = open(path, O_RDWR | O_CREAT, 0700);
385 
386 	if (fd < 0)
387 		return;
388 
389 	ATF_REQUIRE(write(fd, "XXX", 3) == 3);
390 	ATF_REQUIRE(close(fd) == 0);
391 	ATF_REQUIRE(chmod(path, 0444) == 0);
392 
393 	fd = open(path, O_RDONLY);
394 	ATF_REQUIRE(fd != -1);
395 
396 	map = mmap(NULL, 3, PROT_NONE, MAP_FILE | MAP_SHARED, fd, 0);
397 	ATF_REQUIRE(map != MAP_FAILED);
398 
399 	pid = fork();
400 
401 	ATF_REQUIRE(pid >= 0);
402 
403 	if (pid == 0) {
404 		ATF_REQUIRE(signal(SIGSEGV, map_sighandler) != SIG_ERR);
405 		ATF_REQUIRE(strlcpy(buf, map, sizeof(buf)) != 0);
406 	}
407 
408 	(void)wait(&sta);
409 
410 	ATF_REQUIRE(WIFEXITED(sta) != 0);
411 	ATF_REQUIRE(WEXITSTATUS(sta) == SIGSEGV);
412 	ATF_REQUIRE(munmap(map, 3) == 0);
413 }
414 
415 ATF_TC_CLEANUP(mmap_prot_3, tc)
416 {
417 	(void)unlink(path);
418 }
419 
420 ATF_TC_WITH_CLEANUP(mmap_truncate);
421 ATF_TC_HEAD(mmap_truncate, tc)
422 {
423 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) and ftruncate(2)");
424 }
425 
426 ATF_TC_BODY(mmap_truncate, tc)
427 {
428 	char *map;
429 	long i;
430 	int fd;
431 
432 	fd = open(path, O_RDWR | O_CREAT, 0700);
433 
434 	if (fd < 0)
435 		return;
436 
437 	/*
438 	 * See that ftruncate(2) works
439 	 * while the file is mapped.
440 	 */
441 	ATF_REQUIRE(ftruncate(fd, page) == 0);
442 
443 	map = mmap(NULL, page, PROT_READ | PROT_WRITE, MAP_FILE|MAP_PRIVATE,
444 	     fd, 0);
445 	ATF_REQUIRE(map != MAP_FAILED);
446 
447 	for (i = 0; i < page; i++)
448 		map[i] = 'x';
449 
450 	ATF_REQUIRE(ftruncate(fd, 0) == 0);
451 	ATF_REQUIRE(ftruncate(fd, page / 8) == 0);
452 	ATF_REQUIRE(ftruncate(fd, page / 4) == 0);
453 	ATF_REQUIRE(ftruncate(fd, page / 2) == 0);
454 	ATF_REQUIRE(ftruncate(fd, page / 12) == 0);
455 	ATF_REQUIRE(ftruncate(fd, page / 64) == 0);
456 
457 	(void)munmap(map, page);
458 	ATF_REQUIRE(close(fd) == 0);
459 }
460 
461 ATF_TC_CLEANUP(mmap_truncate, tc)
462 {
463 	(void)unlink(path);
464 }
465 
466 ATF_TC_WITH_CLEANUP(mmap_truncate_signal);
467 ATF_TC_HEAD(mmap_truncate_signal, tc)
468 {
469 	atf_tc_set_md_var(tc, "descr",
470 	    "Test mmap(2) ftruncate(2) causing signal");
471 }
472 
473 ATF_TC_BODY(mmap_truncate_signal, tc)
474 {
475 	char *map;
476 	long i;
477 	int fd, sta;
478 	pid_t pid;
479 
480 	fd = open(path, O_RDWR | O_CREAT, 0700);
481 
482 	if (fd < 0)
483 		return;
484 
485 	ATF_REQUIRE(write(fd, "foo\n", 5) == 5);
486 
487 	map = mmap(NULL, page, PROT_READ, MAP_FILE|MAP_PRIVATE, fd, 0);
488 	ATF_REQUIRE(map != MAP_FAILED);
489 
490 	sta = 0;
491 	for (i = 0; i < 5; i++)
492 		sta += map[i];
493 	ATF_REQUIRE(sta == 334);
494 
495 	ATF_REQUIRE(ftruncate(fd, 0) == 0);
496 	pid = fork();
497 	ATF_REQUIRE(pid >= 0);
498 
499 	if (pid == 0) {
500 		ATF_REQUIRE(signal(SIGBUS, map_sighandler) != SIG_ERR);
501 		ATF_REQUIRE(signal(SIGSEGV, map_sighandler) != SIG_ERR);
502 		sta = 0;
503 		for (i = 0; i < page; i++)
504 			sta += map[i];
505 		/* child never will get this far, but the compiler will
506 		   not know, so better use the values calculated to
507 		   prevent the access to be optimized out */
508 		ATF_REQUIRE(i == 0);
509 		ATF_REQUIRE(sta == 0);
510 		(void)munmap(map, page);
511 		(void)close(fd);
512 		return;
513 	}
514 
515 	(void)wait(&sta);
516 
517 	ATF_REQUIRE(WIFEXITED(sta) != 0);
518 	if (WEXITSTATUS(sta) == SIGSEGV)
519 		atf_tc_fail("child process got SIGSEGV instead of SIGBUS");
520 	ATF_REQUIRE(WEXITSTATUS(sta) == SIGBUS);
521 	ATF_REQUIRE(munmap(map, page) == 0);
522 	ATF_REQUIRE(close(fd) == 0);
523 }
524 
525 ATF_TC_CLEANUP(mmap_truncate_signal, tc)
526 {
527 	(void)unlink(path);
528 }
529 
530 ATF_TC(mmap_va0);
531 ATF_TC_HEAD(mmap_va0, tc)
532 {
533 	atf_tc_set_md_var(tc, "descr", "Test mmap(2) and vm.user_va0_disable");
534 }
535 
536 ATF_TC_BODY(mmap_va0, tc)
537 {
538 	int flags = MAP_ANON | MAP_FIXED | MAP_PRIVATE;
539 	size_t len = sizeof(int);
540 	void *map;
541 	int val;
542 
543 	/*
544 	 * Make an anonymous fixed mapping at zero address. If the address
545 	 * is restricted as noted in security(7), the syscall should fail.
546 	 */
547 	if (sysctlbyname("vm.user_va0_disable", &val, &len, NULL, 0) != 0)
548 		atf_tc_fail("failed to read vm.user_va0_disable");
549 
550 	map = mmap(NULL, page, PROT_EXEC, flags, -1, 0);
551 	map_check(map, val);
552 
553 	map = mmap(NULL, page, PROT_READ, flags, -1, 0);
554 	map_check(map, val);
555 
556 	map = mmap(NULL, page, PROT_WRITE, flags, -1, 0);
557 	map_check(map, val);
558 
559 	map = mmap(NULL, page, PROT_READ|PROT_WRITE, flags, -1, 0);
560 	map_check(map, val);
561 
562 	map = mmap(NULL, page, PROT_EXEC|PROT_READ|PROT_WRITE, flags, -1, 0);
563 	map_check(map, val);
564 }
565 
566 ATF_TP_ADD_TCS(tp)
567 {
568 	page = sysconf(_SC_PAGESIZE);
569 	ATF_REQUIRE(page >= 0);
570 
571 	ATF_TP_ADD_TC(tp, mmap_block);
572 	ATF_TP_ADD_TC(tp, mmap_err);
573 	ATF_TP_ADD_TC(tp, mmap_loan);
574 	ATF_TP_ADD_TC(tp, mmap_prot_1);
575 	ATF_TP_ADD_TC(tp, mmap_prot_2);
576 	ATF_TP_ADD_TC(tp, mmap_prot_3);
577 	ATF_TP_ADD_TC(tp, mmap_truncate);
578 	ATF_TP_ADD_TC(tp, mmap_truncate_signal);
579 #ifndef __OpenBSD__
580 	/* sysctl vm.user_va0_disable not available */
581 	ATF_TP_ADD_TC(tp, mmap_va0);
582 #endif
583 
584 	return atf_no_error();
585 }
586