1 /* $NetBSD: t_mlock.c,v 1.6 2016/08/09 12:02:44 kre 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 1.6 2016/08/09 12:02:44 kre 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 #include <limits.h> 51 #define _KMEMUSER 52 #include <machine/vmparam.h> 53 #endif 54 55 static long page = 0; 56 57 #ifdef __FreeBSD__ 58 #define VM_MAX_WIRED "vm.max_wired" 59 60 static void 61 vm_max_wired_sysctl(int *old_value, int *new_value) 62 { 63 size_t old_len; 64 size_t new_len = (new_value == NULL ? 0 : sizeof(int)); 65 66 if (old_value == NULL) 67 printf("Setting the new value to %d\n", *new_value); 68 else { 69 ATF_REQUIRE_MSG(sysctlbyname(VM_MAX_WIRED, NULL, &old_len, 70 new_value, new_len) == 0, 71 "sysctlbyname(%s) failed: %s", VM_MAX_WIRED, strerror(errno)); 72 } 73 74 ATF_REQUIRE_MSG(sysctlbyname(VM_MAX_WIRED, old_value, &old_len, 75 new_value, new_len) == 0, 76 "sysctlbyname(%s) failed: %s", VM_MAX_WIRED, strerror(errno)); 77 78 if (old_value != NULL) 79 printf("Saved the old value (%d)\n", *old_value); 80 } 81 82 static void 83 set_vm_max_wired(int new_value) 84 { 85 FILE *fp; 86 int old_value; 87 88 fp = fopen(VM_MAX_WIRED, "w"); 89 if (fp == NULL) { 90 atf_tc_skip("could not open %s for writing: %s", 91 VM_MAX_WIRED, strerror(errno)); 92 return; 93 } 94 95 vm_max_wired_sysctl(&old_value, NULL); 96 97 ATF_REQUIRE_MSG(fprintf(fp, "%d", old_value) > 0, 98 "saving %s failed", VM_MAX_WIRED); 99 100 fclose(fp); 101 102 vm_max_wired_sysctl(NULL, &new_value); 103 } 104 105 static void 106 restore_vm_max_wired(void) 107 { 108 FILE *fp; 109 int saved_max_wired; 110 111 fp = fopen(VM_MAX_WIRED, "r"); 112 if (fp == NULL) { 113 perror("fopen failed\n"); 114 return; 115 } 116 117 if (fscanf(fp, "%d", &saved_max_wired) != 1) { 118 perror("fscanf failed\n"); 119 fclose(fp); 120 return; 121 } 122 123 fclose(fp); 124 printf("old value in %s: %d\n", VM_MAX_WIRED, saved_max_wired); 125 126 if (saved_max_wired == 0) /* This will cripple the test host */ 127 return; 128 129 vm_max_wired_sysctl(NULL, &saved_max_wired); 130 } 131 #endif 132 133 ATF_TC(mlock_clip); 134 ATF_TC_HEAD(mlock_clip, tc) 135 { 136 atf_tc_set_md_var(tc, "descr", "Test with mlock(2) that UVM only " 137 "clips if the clip address is within the entry (PR kern/44788)"); 138 } 139 140 ATF_TC_BODY(mlock_clip, tc) 141 { 142 void *buf; 143 144 buf = malloc(page); 145 ATF_REQUIRE(buf != NULL); 146 147 if (page < 1024) 148 atf_tc_skip("page size too small"); 149 150 for (size_t i = page; i >= 1; i = i - 1024) { 151 (void)mlock(buf, page - i); 152 (void)munlock(buf, page - i); 153 } 154 155 free(buf); 156 } 157 158 #ifdef __FreeBSD__ 159 ATF_TC_WITH_CLEANUP(mlock_err); 160 #else 161 ATF_TC(mlock_err); 162 #endif 163 ATF_TC_HEAD(mlock_err, tc) 164 { 165 atf_tc_set_md_var(tc, "descr", 166 "Test error conditions in mlock(2) and munlock(2)"); 167 #ifdef __FreeBSD__ 168 atf_tc_set_md_var(tc, "require.config", "allow_sysctl_side_effects"); 169 atf_tc_set_md_var(tc, "require.user", "root"); 170 #endif 171 } 172 173 ATF_TC_BODY(mlock_err, tc) 174 { 175 #ifdef __NetBSD__ 176 unsigned long vmin = 0; 177 size_t len = sizeof(vmin); 178 #endif 179 #if !defined(__aarch64__) && !defined(__riscv__) 180 void *invalid_ptr; 181 #endif 182 int null_errno = ENOMEM; /* error expected for NULL */ 183 void *buf; 184 185 #ifdef __FreeBSD__ 186 #ifdef VM_MIN_ADDRESS 187 if ((uintptr_t)VM_MIN_ADDRESS > 0) 188 null_errno = EINVAL; /* NULL is not inside user VM */ 189 #endif 190 /* Set max_wired really really high to avoid EAGAIN */ 191 set_vm_max_wired(INT_MAX); 192 #else 193 if (sysctlbyname("vm.minaddress", &vmin, &len, NULL, 0) != 0) 194 atf_tc_fail("failed to read vm.minaddress"); 195 /* 196 * Any bad address must return ENOMEM (for lock & unlock) 197 */ 198 errno = 0; 199 ATF_REQUIRE_ERRNO(ENOMEM, mlock(NULL, page) == -1); 200 201 if (vmin > 0) 202 null_errno = EINVAL; /* NULL is not inside user VM */ 203 #endif 204 205 errno = 0; 206 ATF_REQUIRE_ERRNO(ENOMEM, mlock((char *)0, page) == -1); 207 208 errno = 0; 209 ATF_REQUIRE_ERRNO(ENOMEM, mlock((char *)-1, page) == -1); 210 211 errno = 0; 212 ATF_REQUIRE_ERRNO(ENOMEM, munlock(NULL, page) == -1); 213 214 errno = 0; 215 ATF_REQUIRE_ERRNO(ENOMEM, munlock((char *)0, page) == -1); 216 217 errno = 0; 218 ATF_REQUIRE_ERRNO(ENOMEM, munlock((char *)-1, page) == -1); 219 220 buf = malloc(page); 221 ATF_REQUIRE(buf != NULL); 222 223 /* 224 * unlocking memory that is not locked is an error... 225 */ 226 227 errno = 0; 228 ATF_REQUIRE_ERRNO(ENOMEM, munlock(buf, page) == -1); 229 230 /* There is no sbrk on AArch64 and RISC-V */ 231 #if !defined(__aarch64__) && !defined(__riscv__) 232 /* 233 * These are permitted to fail (EINVAL) but do not on NetBSD 234 */ 235 ATF_REQUIRE(mlock((void *)(((uintptr_t)buf) + page/3), page/5) == 0); 236 ATF_REQUIRE(munlock((void *)(((uintptr_t)buf) + page/3), page/5) == 0); 237 238 (void)free(buf); 239 240 /* 241 * Try to create a pointer to an unmapped page - first after current 242 * brk will likely do. 243 */ 244 invalid_ptr = (void*)(((uintptr_t)sbrk(0)+page) & ~(page-1)); 245 printf("testing with (hopefully) invalid pointer %p\n", invalid_ptr); 246 247 errno = 0; 248 ATF_REQUIRE_ERRNO(ENOMEM, mlock(invalid_ptr, page) == -1); 249 250 errno = 0; 251 ATF_REQUIRE_ERRNO(ENOMEM, munlock(invalid_ptr, page) == -1); 252 #endif 253 } 254 255 #ifdef __FreeBSD__ 256 ATF_TC_CLEANUP(mlock_err, tc) 257 { 258 259 restore_vm_max_wired(); 260 } 261 #endif 262 263 ATF_TC(mlock_limits); 264 ATF_TC_HEAD(mlock_limits, tc) 265 { 266 atf_tc_set_md_var(tc, "descr", "Test system limits with mlock(2)"); 267 } 268 269 ATF_TC_BODY(mlock_limits, tc) 270 { 271 struct rlimit res; 272 void *buf; 273 pid_t pid; 274 int sta; 275 276 buf = malloc(page); 277 ATF_REQUIRE(buf != NULL); 278 279 pid = fork(); 280 ATF_REQUIRE(pid >= 0); 281 282 if (pid == 0) { 283 284 for (ssize_t i = page; i >= 2; i -= 100) { 285 286 res.rlim_cur = i - 1; 287 res.rlim_max = i - 1; 288 289 (void)fprintf(stderr, "trying to lock %zd bytes " 290 "with %zu byte limit\n", i, (size_t)res.rlim_cur); 291 292 if (setrlimit(RLIMIT_MEMLOCK, &res) != 0) 293 _exit(EXIT_FAILURE); 294 295 errno = 0; 296 297 #ifdef __FreeBSD__ 298 /* 299 * NetBSD doesn't conform to POSIX with ENOMEM requirement; 300 * FreeBSD does. 301 * 302 * See: NetBSD PR # kern/48962 for more details. 303 */ 304 if (mlock(buf, i) != -1 || errno != ENOMEM) { 305 #else 306 if (mlock(buf, i) != -1 || errno != EAGAIN) { 307 #endif 308 (void)munlock(buf, i); 309 _exit(EXIT_FAILURE); 310 } 311 } 312 313 _exit(EXIT_SUCCESS); 314 } 315 316 (void)wait(&sta); 317 318 if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS) 319 atf_tc_fail("mlock(2) locked beyond system limits"); 320 321 free(buf); 322 } 323 324 #ifdef __FreeBSD__ 325 ATF_TC_WITH_CLEANUP(mlock_mmap); 326 #else 327 ATF_TC(mlock_mmap); 328 #endif 329 ATF_TC_HEAD(mlock_mmap, tc) 330 { 331 atf_tc_set_md_var(tc, "descr", "Test mlock(2)-mmap(2) interaction"); 332 #ifdef __FreeBSD__ 333 atf_tc_set_md_var(tc, "require.config", "allow_sysctl_side_effects"); 334 atf_tc_set_md_var(tc, "require.user", "root"); 335 #endif 336 } 337 338 ATF_TC_BODY(mlock_mmap, tc) 339 { 340 #ifdef __NetBSD__ 341 static const int flags = MAP_ANON | MAP_PRIVATE | MAP_WIRED; 342 #else 343 static const int flags = MAP_ANON | MAP_PRIVATE; 344 #endif 345 void *buf; 346 347 #ifdef __FreeBSD__ 348 /* Set max_wired really really high to avoid EAGAIN */ 349 set_vm_max_wired(INT_MAX); 350 #endif 351 352 /* 353 * Make a wired RW mapping and check that mlock(2) 354 * does not fail for the (already locked) mapping. 355 */ 356 buf = mmap(NULL, page, PROT_READ | PROT_WRITE, flags, -1, 0); 357 358 ATF_REQUIRE(buf != MAP_FAILED); 359 #ifdef __FreeBSD__ 360 /* 361 * The duplicate mlock call is added to ensure that the call works 362 * as described above without MAP_WIRED support. 363 */ 364 ATF_REQUIRE(mlock(buf, page) == 0); 365 #endif 366 ATF_REQUIRE(mlock(buf, page) == 0); 367 ATF_REQUIRE(munlock(buf, page) == 0); 368 ATF_REQUIRE(munmap(buf, page) == 0); 369 ATF_REQUIRE(munlock(buf, page) != 0); 370 371 /* 372 * But it should be impossible to mlock(2) a PROT_NONE mapping. 373 */ 374 buf = mmap(NULL, page, PROT_NONE, flags, -1, 0); 375 376 ATF_REQUIRE(buf != MAP_FAILED); 377 #ifdef __FreeBSD__ 378 ATF_REQUIRE_ERRNO(ENOMEM, mlock(buf, page) != 0); 379 #else 380 ATF_REQUIRE(mlock(buf, page) != 0); 381 #endif 382 ATF_REQUIRE(munmap(buf, page) == 0); 383 } 384 385 #ifdef __FreeBSD__ 386 ATF_TC_CLEANUP(mlock_mmap, tc) 387 { 388 389 restore_vm_max_wired(); 390 } 391 #endif 392 393 #ifdef __FreeBSD__ 394 ATF_TC_WITH_CLEANUP(mlock_nested); 395 #else 396 ATF_TC(mlock_nested); 397 #endif 398 ATF_TC_HEAD(mlock_nested, tc) 399 { 400 atf_tc_set_md_var(tc, "descr", 401 "Test that consecutive mlock(2) calls succeed"); 402 #ifdef __FreeBSD__ 403 atf_tc_set_md_var(tc, "require.config", "allow_sysctl_side_effects"); 404 atf_tc_set_md_var(tc, "require.user", "root"); 405 #endif 406 } 407 408 ATF_TC_BODY(mlock_nested, tc) 409 { 410 const size_t maxiter = 100; 411 void *buf; 412 413 #ifdef __FreeBSD__ 414 /* Set max_wired really really high to avoid EAGAIN */ 415 set_vm_max_wired(INT_MAX); 416 #endif 417 418 buf = malloc(page); 419 ATF_REQUIRE(buf != NULL); 420 421 for (size_t i = 0; i < maxiter; i++) 422 ATF_REQUIRE(mlock(buf, page) == 0); 423 424 ATF_REQUIRE(munlock(buf, page) == 0); 425 free(buf); 426 } 427 428 #ifdef __FreeBSD__ 429 ATF_TC_CLEANUP(mlock_nested, tc) 430 { 431 432 restore_vm_max_wired(); 433 } 434 #endif 435 436 ATF_TP_ADD_TCS(tp) 437 { 438 439 page = sysconf(_SC_PAGESIZE); 440 ATF_REQUIRE(page >= 0); 441 442 ATF_TP_ADD_TC(tp, mlock_clip); 443 ATF_TP_ADD_TC(tp, mlock_err); 444 ATF_TP_ADD_TC(tp, mlock_limits); 445 ATF_TP_ADD_TC(tp, mlock_mmap); 446 ATF_TP_ADD_TC(tp, mlock_nested); 447 448 return atf_no_error(); 449 } 450