t_mlock.c revision 313498
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 55static long page = 0; 56 57#ifdef __FreeBSD__ 58#define VM_MAX_WIRED "vm.max_wired" 59 60static void 61vm_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 82static void 83set_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 105static void 106restore_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 133ATF_TC(mlock_clip); 134ATF_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 140ATF_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__ 159ATF_TC_WITH_CLEANUP(mlock_err); 160#else 161ATF_TC(mlock_err); 162#endif 163ATF_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 173ATF_TC_BODY(mlock_err, tc) 174{ 175#ifdef __NetBSD__ 176 unsigned long vmin = 0; 177 size_t len = sizeof(vmin); 178#endif 179 void *invalid_ptr; 180 int null_errno = ENOMEM; /* error expected for NULL */ 181 void *buf; 182 183#ifdef __FreeBSD__ 184#ifdef VM_MIN_ADDRESS 185 if ((uintptr_t)VM_MIN_ADDRESS > 0) 186 null_errno = EINVAL; /* NULL is not inside user VM */ 187#endif 188 /* Set max_wired really really high to avoid EAGAIN */ 189 set_vm_max_wired(INT_MAX); 190#else 191 if (sysctlbyname("vm.minaddress", &vmin, &len, NULL, 0) != 0) 192 atf_tc_fail("failed to read vm.minaddress"); 193 /* 194 * Any bad address must return ENOMEM (for lock & unlock) 195 */ 196 errno = 0; 197 ATF_REQUIRE_ERRNO(ENOMEM, mlock(NULL, page) == -1); 198 199 if (vmin > 0) 200 null_errno = EINVAL; /* NULL is not inside user VM */ 201#endif 202 203 errno = 0; 204 ATF_REQUIRE_ERRNO(ENOMEM, mlock((char *)0, page) == -1); 205 206 errno = 0; 207 ATF_REQUIRE_ERRNO(ENOMEM, mlock((char *)-1, page) == -1); 208 209 errno = 0; 210 ATF_REQUIRE_ERRNO(ENOMEM, munlock(NULL, page) == -1); 211 212 errno = 0; 213 ATF_REQUIRE_ERRNO(ENOMEM, munlock((char *)0, page) == -1); 214 215 errno = 0; 216 ATF_REQUIRE_ERRNO(ENOMEM, munlock((char *)-1, page) == -1); 217 218 buf = malloc(page); 219 ATF_REQUIRE(buf != NULL); 220 221 /* 222 * unlocking memory that is not locked is an error... 223 */ 224 225 errno = 0; 226 ATF_REQUIRE_ERRNO(ENOMEM, munlock(buf, page) == -1); 227 228 /* 229 * These are permitted to fail (EINVAL) but do not on NetBSD 230 */ 231 ATF_REQUIRE(mlock((void *)(((uintptr_t)buf) + page/3), page/5) == 0); 232 ATF_REQUIRE(munlock((void *)(((uintptr_t)buf) + page/3), page/5) == 0); 233 234 (void)free(buf); 235 236 /* 237 * Try to create a pointer to an unmapped page - first after current 238 * brk will likely do. 239 */ 240 invalid_ptr = (void*)(((uintptr_t)sbrk(0)+page) & ~(page-1)); 241 printf("testing with (hopefully) invalid pointer %p\n", invalid_ptr); 242 243 errno = 0; 244 ATF_REQUIRE_ERRNO(ENOMEM, mlock(invalid_ptr, page) == -1); 245 246 errno = 0; 247 ATF_REQUIRE_ERRNO(ENOMEM, munlock(invalid_ptr, page) == -1); 248} 249 250#ifdef __FreeBSD__ 251ATF_TC_CLEANUP(mlock_err, tc) 252{ 253 254 restore_vm_max_wired(); 255} 256#endif 257 258ATF_TC(mlock_limits); 259ATF_TC_HEAD(mlock_limits, tc) 260{ 261 atf_tc_set_md_var(tc, "descr", "Test system limits with mlock(2)"); 262} 263 264ATF_TC_BODY(mlock_limits, tc) 265{ 266 struct rlimit res; 267 void *buf; 268 pid_t pid; 269 int sta; 270 271 buf = malloc(page); 272 ATF_REQUIRE(buf != NULL); 273 274 pid = fork(); 275 ATF_REQUIRE(pid >= 0); 276 277 if (pid == 0) { 278 279 for (ssize_t i = page; i >= 2; i -= 100) { 280 281 res.rlim_cur = i - 1; 282 res.rlim_max = i - 1; 283 284 (void)fprintf(stderr, "trying to lock %zd bytes " 285 "with %zu byte limit\n", i, (size_t)res.rlim_cur); 286 287 if (setrlimit(RLIMIT_MEMLOCK, &res) != 0) 288 _exit(EXIT_FAILURE); 289 290 errno = 0; 291 292#ifdef __FreeBSD__ 293 /* 294 * NetBSD doesn't conform to POSIX with ENOMEM requirement; 295 * FreeBSD does. 296 * 297 * See: NetBSD PR # kern/48962 for more details. 298 */ 299 if (mlock(buf, i) != -1 || errno != ENOMEM) { 300#else 301 if (mlock(buf, i) != -1 || errno != EAGAIN) { 302#endif 303 (void)munlock(buf, i); 304 _exit(EXIT_FAILURE); 305 } 306 } 307 308 _exit(EXIT_SUCCESS); 309 } 310 311 (void)wait(&sta); 312 313 if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS) 314 atf_tc_fail("mlock(2) locked beyond system limits"); 315 316 free(buf); 317} 318 319#ifdef __FreeBSD__ 320ATF_TC_WITH_CLEANUP(mlock_mmap); 321#else 322ATF_TC(mlock_mmap); 323#endif 324ATF_TC_HEAD(mlock_mmap, tc) 325{ 326 atf_tc_set_md_var(tc, "descr", "Test mlock(2)-mmap(2) interaction"); 327#ifdef __FreeBSD__ 328 atf_tc_set_md_var(tc, "require.config", "allow_sysctl_side_effects"); 329 atf_tc_set_md_var(tc, "require.user", "root"); 330#endif 331} 332 333ATF_TC_BODY(mlock_mmap, tc) 334{ 335#ifdef __NetBSD__ 336 static const int flags = MAP_ANON | MAP_PRIVATE | MAP_WIRED; 337#else 338 static const int flags = MAP_ANON | MAP_PRIVATE; 339#endif 340 void *buf; 341 342#ifdef __FreeBSD__ 343 /* Set max_wired really really high to avoid EAGAIN */ 344 set_vm_max_wired(INT_MAX); 345#endif 346 347 /* 348 * Make a wired RW mapping and check that mlock(2) 349 * does not fail for the (already locked) mapping. 350 */ 351 buf = mmap(NULL, page, PROT_READ | PROT_WRITE, flags, -1, 0); 352 353 ATF_REQUIRE(buf != MAP_FAILED); 354#ifdef __FreeBSD__ 355 /* 356 * The duplicate mlock call is added to ensure that the call works 357 * as described above without MAP_WIRED support. 358 */ 359 ATF_REQUIRE(mlock(buf, page) == 0); 360#endif 361 ATF_REQUIRE(mlock(buf, page) == 0); 362 ATF_REQUIRE(munlock(buf, page) == 0); 363 ATF_REQUIRE(munmap(buf, page) == 0); 364 ATF_REQUIRE(munlock(buf, page) != 0); 365 366 /* 367 * But it should be impossible to mlock(2) a PROT_NONE mapping. 368 */ 369 buf = mmap(NULL, page, PROT_NONE, flags, -1, 0); 370 371 ATF_REQUIRE(buf != MAP_FAILED); 372#ifdef __FreeBSD__ 373 ATF_REQUIRE_ERRNO(ENOMEM, mlock(buf, page) != 0); 374#else 375 ATF_REQUIRE(mlock(buf, page) != 0); 376#endif 377 ATF_REQUIRE(munmap(buf, page) == 0); 378} 379 380#ifdef __FreeBSD__ 381ATF_TC_CLEANUP(mlock_mmap, tc) 382{ 383 384 restore_vm_max_wired(); 385} 386#endif 387 388#ifdef __FreeBSD__ 389ATF_TC_WITH_CLEANUP(mlock_nested); 390#else 391ATF_TC(mlock_nested); 392#endif 393ATF_TC_HEAD(mlock_nested, tc) 394{ 395 atf_tc_set_md_var(tc, "descr", 396 "Test that consecutive mlock(2) calls succeed"); 397#ifdef __FreeBSD__ 398 atf_tc_set_md_var(tc, "require.config", "allow_sysctl_side_effects"); 399 atf_tc_set_md_var(tc, "require.user", "root"); 400#endif 401} 402 403ATF_TC_BODY(mlock_nested, tc) 404{ 405 const size_t maxiter = 100; 406 void *buf; 407 408#ifdef __FreeBSD__ 409 /* Set max_wired really really high to avoid EAGAIN */ 410 set_vm_max_wired(INT_MAX); 411#endif 412 413 buf = malloc(page); 414 ATF_REQUIRE(buf != NULL); 415 416 for (size_t i = 0; i < maxiter; i++) 417 ATF_REQUIRE(mlock(buf, page) == 0); 418 419 ATF_REQUIRE(munlock(buf, page) == 0); 420 free(buf); 421} 422 423#ifdef __FreeBSD__ 424ATF_TC_CLEANUP(mlock_nested, tc) 425{ 426 427 restore_vm_max_wired(); 428} 429#endif 430 431ATF_TP_ADD_TCS(tp) 432{ 433 434 page = sysconf(_SC_PAGESIZE); 435 ATF_REQUIRE(page >= 0); 436 437 ATF_TP_ADD_TC(tp, mlock_clip); 438 ATF_TP_ADD_TC(tp, mlock_err); 439 ATF_TP_ADD_TC(tp, mlock_limits); 440 ATF_TP_ADD_TC(tp, mlock_mmap); 441 ATF_TP_ADD_TC(tp, mlock_nested); 442 443 return atf_no_error(); 444} 445