1 /* $NetBSD: kern_module.c,v 1.51 2009/10/03 00:06:37 elad Exp $ */ 2 3 /*- 4 * Copyright (c) 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software developed for The NetBSD Foundation 8 * by Andrew Doran. 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 * Kernel module support. 34 */ 35 36 #include <sys/cdefs.h> 37 __KERNEL_RCSID(0, "$NetBSD: kern_module.c,v 1.51 2009/10/03 00:06:37 elad Exp $"); 38 39 #ifdef _KERNEL_OPT 40 #include "opt_ddb.h" 41 #include "opt_modular.h" 42 #endif 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/fcntl.h> 48 #include <sys/proc.h> 49 #include <sys/kauth.h> 50 #include <sys/kobj.h> 51 #include <sys/kmem.h> 52 #include <sys/module.h> 53 #include <sys/kauth.h> 54 #include <sys/kthread.h> 55 #include <sys/sysctl.h> 56 #include <sys/namei.h> 57 #include <sys/lock.h> 58 #include <sys/vnode.h> 59 #include <sys/stat.h> 60 61 #include <uvm/uvm_extern.h> 62 63 #include <machine/stdarg.h> 64 65 struct vm_map *module_map; 66 67 struct modlist module_list = TAILQ_HEAD_INITIALIZER(module_list); 68 struct modlist module_bootlist = TAILQ_HEAD_INITIALIZER(module_bootlist); 69 static module_t *module_active; 70 static char module_base[64]; 71 static int module_verbose_on; 72 static int module_autoload_on = 1; 73 u_int module_count; 74 kmutex_t module_lock; 75 u_int module_autotime = 10; 76 u_int module_gen = 1; 77 static kcondvar_t module_thread_cv; 78 static kmutex_t module_thread_lock; 79 static int module_thread_ticks; 80 81 static kauth_listener_t module_listener; 82 83 /* Ensure that the kernel's link set isn't empty. */ 84 static modinfo_t module_dummy; 85 __link_set_add_rodata(modules, module_dummy); 86 87 static module_t *module_lookup(const char *); 88 static int module_do_load(const char *, bool, int, prop_dictionary_t, 89 module_t **, modclass_t class, bool); 90 static int module_do_unload(const char *); 91 static void module_error(const char *, ...) 92 __attribute__((__format__(__printf__,1,2))); 93 static void module_print(const char *, ...) 94 __attribute__((__format__(__printf__,1,2))); 95 static int module_do_builtin(const char *, module_t **); 96 static int module_fetch_info(module_t *); 97 static void module_thread(void *); 98 static int module_load_plist_file(const char *, const bool, void **, 99 size_t *); 100 static bool module_merge_dicts(prop_dictionary_t, const prop_dictionary_t); 101 102 /* 103 * module_error: 104 * 105 * Utility function: log an error. 106 */ 107 static void 108 module_error(const char *fmt, ...) 109 { 110 va_list ap; 111 112 va_start(ap, fmt); 113 printf("WARNING: module error: "); 114 vprintf(fmt, ap); 115 printf("\n"); 116 va_end(ap); 117 } 118 119 /* 120 * module_print: 121 * 122 * Utility function: log verbose output. 123 */ 124 static void 125 module_print(const char *fmt, ...) 126 { 127 va_list ap; 128 129 if (module_verbose_on) { 130 va_start(ap, fmt); 131 printf("DEBUG: module: "); 132 vprintf(fmt, ap); 133 printf("\n"); 134 va_end(ap); 135 } 136 } 137 138 /* 139 * module_init: 140 * 141 * Initialize the module subsystem. 142 */ 143 void 144 module_init(void) 145 { 146 extern struct vm_map *module_map; 147 148 if (module_map == NULL) { 149 module_map = kernel_map; 150 } 151 mutex_init(&module_lock, MUTEX_DEFAULT, IPL_NONE); 152 cv_init(&module_thread_cv, "modunload"); 153 mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE); 154 #ifdef MODULAR /* XXX */ 155 module_init_md(); 156 #endif 157 158 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 159 snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules", 160 machine, osrelease); 161 #else /* release */ 162 snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules", 163 machine, __NetBSD_Version__ / 100000000, 164 __NetBSD_Version__ / 1000000 % 100); 165 #endif 166 } 167 168 static int 169 module_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 170 void *arg0, void *arg1, void *arg2, void *arg3) 171 { 172 int result; 173 174 result = KAUTH_RESULT_DEFER; 175 176 if (action != KAUTH_SYSTEM_MODULE) 177 return result; 178 179 if ((uintptr_t)arg2 != 0) /* autoload */ 180 result = KAUTH_RESULT_ALLOW; 181 182 return result; 183 } 184 185 /* 186 * module_init2: 187 * 188 * Start the auto unload kthread. 189 */ 190 void 191 module_init2(void) 192 { 193 int error; 194 195 error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread, 196 NULL, NULL, "modunload"); 197 if (error != 0) 198 panic("module_init: %d", error); 199 200 module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM, 201 module_listener_cb, NULL); 202 } 203 204 SYSCTL_SETUP(sysctl_module_setup, "sysctl module setup") 205 { 206 const struct sysctlnode *node = NULL; 207 208 sysctl_createv(clog, 0, NULL, NULL, 209 CTLFLAG_PERMANENT, 210 CTLTYPE_NODE, "kern", NULL, 211 NULL, 0, NULL, 0, 212 CTL_KERN, CTL_EOL); 213 sysctl_createv(clog, 0, NULL, &node, 214 CTLFLAG_PERMANENT, 215 CTLTYPE_NODE, "module", 216 SYSCTL_DESCR("Module options"), 217 NULL, 0, NULL, 0, 218 CTL_KERN, CTL_CREATE, CTL_EOL); 219 220 if (node == NULL) 221 return; 222 223 sysctl_createv(clog, 0, &node, NULL, 224 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 225 CTLTYPE_INT, "autoload", 226 SYSCTL_DESCR("Enable automatic load of modules"), 227 NULL, 0, &module_autoload_on, 0, 228 CTL_CREATE, CTL_EOL); 229 sysctl_createv(clog, 0, &node, NULL, 230 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 231 CTLTYPE_INT, "verbose", 232 SYSCTL_DESCR("Enable verbose output"), 233 NULL, 0, &module_verbose_on, 0, 234 CTL_CREATE, CTL_EOL); 235 } 236 237 /* 238 * module_init_class: 239 * 240 * Initialize all built-in and pre-loaded modules of the 241 * specified class. 242 */ 243 void 244 module_init_class(modclass_t class) 245 { 246 __link_set_decl(modules, modinfo_t); 247 modinfo_t *const *mip, *mi; 248 module_t *mod; 249 250 mutex_enter(&module_lock); 251 /* 252 * Builtins first. These can't depend on pre-loaded modules. 253 */ 254 __link_set_foreach(mip, modules) { 255 mi = *mip; 256 if (mi == &module_dummy) { 257 continue; 258 } 259 if (class != MODULE_CLASS_ANY && class != mi->mi_class) { 260 continue; 261 } 262 (void)module_do_builtin(mi->mi_name, NULL); 263 } 264 /* 265 * Now preloaded modules. These will be pulled off the 266 * list as we call module_do_load(); 267 */ 268 do { 269 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 270 mi = mod->mod_info; 271 if (class != MODULE_CLASS_ANY && 272 class != mi->mi_class) 273 continue; 274 module_do_load(mi->mi_name, false, 0, NULL, NULL, 275 class, false); 276 break; 277 } 278 } while (mod != NULL); 279 mutex_exit(&module_lock); 280 } 281 282 /* 283 * module_compatible: 284 * 285 * Return true if the two supplied kernel versions are said to 286 * have the same binary interface for kernel code. The entire 287 * version is signficant for the development tree (-current), 288 * major and minor versions are significant for official 289 * releases of the system. 290 */ 291 bool 292 module_compatible(int v1, int v2) 293 { 294 295 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 296 return v1 == v2; 297 #else /* release */ 298 return abs(v1 - v2) < 10000; 299 #endif 300 } 301 302 /* 303 * module_load: 304 * 305 * Load a single module from the file system. 306 */ 307 int 308 module_load(const char *filename, int flags, prop_dictionary_t props, 309 modclass_t class) 310 { 311 int error; 312 313 /* Authorize. */ 314 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 315 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 316 if (error != 0) { 317 return error; 318 } 319 320 mutex_enter(&module_lock); 321 error = module_do_load(filename, false, flags, props, NULL, class, 322 false); 323 mutex_exit(&module_lock); 324 325 return error; 326 } 327 328 /* 329 * module_autoload: 330 * 331 * Load a single module from the file system, system initiated. 332 */ 333 int 334 module_autoload(const char *filename, modclass_t class) 335 { 336 int error; 337 338 KASSERT(mutex_owned(&module_lock)); 339 340 /* Nothing if the user has disabled it. */ 341 if (!module_autoload_on) { 342 return EPERM; 343 } 344 345 /* Disallow path seperators and magic symlinks. */ 346 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 347 strchr(filename, '.') != NULL) { 348 return EPERM; 349 } 350 351 /* Authorize. */ 352 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 353 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 354 if (error != 0) { 355 return error; 356 } 357 358 return module_do_load(filename, false, 0, NULL, NULL, class, true); 359 } 360 361 /* 362 * module_unload: 363 * 364 * Find and unload a module by name. 365 */ 366 int 367 module_unload(const char *name) 368 { 369 int error; 370 371 /* Authorize. */ 372 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 373 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 374 if (error != 0) { 375 return error; 376 } 377 378 mutex_enter(&module_lock); 379 error = module_do_unload(name); 380 mutex_exit(&module_lock); 381 382 return error; 383 } 384 385 /* 386 * module_lookup: 387 * 388 * Look up a module by name. 389 */ 390 module_t * 391 module_lookup(const char *name) 392 { 393 module_t *mod; 394 395 KASSERT(mutex_owned(&module_lock)); 396 397 TAILQ_FOREACH(mod, &module_list, mod_chain) { 398 if (strcmp(mod->mod_info->mi_name, name) == 0) { 399 break; 400 } 401 } 402 403 return mod; 404 } 405 406 /* 407 * module_hold: 408 * 409 * Add a single reference to a module. It's the caller's 410 * responsibility to ensure that the reference is dropped 411 * later. 412 */ 413 int 414 module_hold(const char *name) 415 { 416 module_t *mod; 417 418 mutex_enter(&module_lock); 419 mod = module_lookup(name); 420 if (mod == NULL) { 421 mutex_exit(&module_lock); 422 return ENOENT; 423 } 424 mod->mod_refcnt++; 425 mutex_exit(&module_lock); 426 427 return 0; 428 } 429 430 /* 431 * module_rele: 432 * 433 * Release a reference acquired with module_hold(). 434 */ 435 void 436 module_rele(const char *name) 437 { 438 module_t *mod; 439 440 mutex_enter(&module_lock); 441 mod = module_lookup(name); 442 if (mod == NULL) { 443 mutex_exit(&module_lock); 444 panic("module_rele: gone"); 445 } 446 mod->mod_refcnt--; 447 mutex_exit(&module_lock); 448 } 449 450 /* 451 * module_enqueue: 452 * 453 * Put a module onto the global list and update counters. 454 */ 455 static void 456 module_enqueue(module_t *mod) 457 { 458 int i; 459 460 /* 461 * If there are requisite modules, put at the head of the queue. 462 * This is so that autounload can unload requisite modules with 463 * only one pass through the queue. 464 */ 465 if (mod->mod_nrequired) { 466 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 467 468 /* Add references to the requisite modules. */ 469 for (i = 0; i < mod->mod_nrequired; i++) { 470 KASSERT(mod->mod_required[i] != NULL); 471 mod->mod_required[i]->mod_refcnt++; 472 } 473 } else { 474 TAILQ_INSERT_TAIL(&module_list, mod, mod_chain); 475 } 476 module_count++; 477 module_gen++; 478 } 479 480 /* 481 * module_do_builtin: 482 * 483 * Initialize a single module from the list of modules that are 484 * built into the kernel (linked into the kernel image). 485 */ 486 static int 487 module_do_builtin(const char *name, module_t **modp) 488 { 489 __link_set_decl(modules, modinfo_t); 490 modinfo_t *const *mip; 491 const char *p, *s; 492 char buf[MAXMODNAME]; 493 modinfo_t *mi; 494 module_t *mod, *mod2; 495 size_t len; 496 int error; 497 498 KASSERT(mutex_owned(&module_lock)); 499 500 /* 501 * Check to see if already loaded. 502 */ 503 if ((mod = module_lookup(name)) != NULL) { 504 if (modp != NULL) { 505 *modp = mod; 506 } 507 return 0; 508 } 509 510 /* 511 * Search the list to see if we have a module by this name. 512 */ 513 error = ENOENT; 514 __link_set_foreach(mip, modules) { 515 mi = *mip; 516 if (mi == &module_dummy) { 517 continue; 518 } 519 if (strcmp(mi->mi_name, name) == 0) { 520 error = 0; 521 break; 522 } 523 } 524 if (error != 0) { 525 module_error("can't find `%s'", name); 526 return error; 527 } 528 529 /* 530 * Initialize pre-requisites. 531 */ 532 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 533 if (mod == NULL) { 534 module_error("out of memory for `%s'", name); 535 return ENOMEM; 536 } 537 if (modp != NULL) { 538 *modp = mod; 539 } 540 if (mi->mi_required != NULL) { 541 for (s = mi->mi_required; *s != '\0'; s = p) { 542 if (*s == ',') 543 s++; 544 p = s; 545 while (*p != '\0' && *p != ',') 546 p++; 547 len = min(p - s + 1, sizeof(buf)); 548 strlcpy(buf, s, len); 549 if (buf[0] == '\0') 550 break; 551 if (mod->mod_nrequired == MAXMODDEPS - 1) { 552 module_error("too many required modules"); 553 kmem_free(mod, sizeof(*mod)); 554 return EINVAL; 555 } 556 error = module_do_builtin(buf, &mod2); 557 if (error != 0) { 558 kmem_free(mod, sizeof(*mod)); 559 return error; 560 } 561 mod->mod_required[mod->mod_nrequired++] = mod2; 562 } 563 } 564 565 /* 566 * Try to initialize the module. 567 */ 568 KASSERT(module_active == NULL); 569 module_active = mod; 570 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, NULL); 571 module_active = NULL; 572 if (error != 0) { 573 module_error("builtin module `%s' " 574 "failed to init", mi->mi_name); 575 kmem_free(mod, sizeof(*mod)); 576 return error; 577 } 578 if (mi->mi_class == MODULE_CLASS_SECMODEL) 579 secmodel_register(); 580 mod->mod_info = mi; 581 mod->mod_source = MODULE_SOURCE_KERNEL; 582 module_enqueue(mod); 583 return 0; 584 } 585 586 /* 587 * module_do_load: 588 * 589 * Helper routine: load a module from the file system, or one 590 * pushed by the boot loader. 591 */ 592 static int 593 module_do_load(const char *name, bool isdep, int flags, 594 prop_dictionary_t props, module_t **modp, modclass_t class, 595 bool autoload) 596 { 597 static TAILQ_HEAD(,module) pending = TAILQ_HEAD_INITIALIZER(pending); 598 static int depth; 599 const int maxdepth = 6; 600 modinfo_t *mi; 601 module_t *mod, *mod2; 602 prop_dictionary_t filedict; 603 void *plist; 604 char buf[MAXMODNAME], *path; 605 const char *s, *p; 606 int error; 607 size_t len, plistlen; 608 bool nochroot; 609 610 KASSERT(mutex_owned(&module_lock)); 611 612 filedict = NULL; 613 path = NULL; 614 error = 0; 615 nochroot = false; 616 617 /* 618 * Avoid recursing too far. 619 */ 620 if (++depth > maxdepth) { 621 module_error("too many required modules"); 622 depth--; 623 return EMLINK; 624 } 625 626 /* 627 * Load the module and link. Before going to the file system, 628 * scan the list of modules loaded by the boot loader. Just 629 * before init is started the list of modules loaded at boot 630 * will be purged. Before init is started we can assume that 631 * `name' is a module name and not a path name. 632 */ 633 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 634 if (strcmp(mod->mod_info->mi_name, name) == 0) { 635 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 636 break; 637 } 638 } 639 if (mod != NULL) { 640 TAILQ_INSERT_TAIL(&pending, mod, mod_chain); 641 } else { 642 /* 643 * If a requisite module, check to see if it is 644 * already present. 645 */ 646 if (isdep) { 647 TAILQ_FOREACH(mod, &module_list, mod_chain) { 648 if (strcmp(mod->mod_info->mi_name, name) == 0) { 649 break; 650 } 651 } 652 if (mod != NULL) { 653 if (modp != NULL) { 654 *modp = mod; 655 } 656 depth--; 657 return 0; 658 } 659 } 660 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 661 if (mod == NULL) { 662 module_error("out of memory for `%s'", name); 663 depth--; 664 return ENOMEM; 665 } 666 path = PNBUF_GET(); 667 if (!autoload) { 668 nochroot = false; 669 snprintf(path, MAXPATHLEN, "%s", name); 670 error = kobj_load_file(&mod->mod_kobj, path, nochroot); 671 } 672 if (autoload || (error == ENOENT)) { 673 nochroot = true; 674 snprintf(path, MAXPATHLEN, "%s/%s/%s.kmod", 675 module_base, name, name); 676 error = kobj_load_file(&mod->mod_kobj, path, nochroot); 677 } 678 if (error != 0) { 679 kmem_free(mod, sizeof(*mod)); 680 depth--; 681 PNBUF_PUT(path); 682 if (autoload) { 683 module_print("Cannot load kernel object `%s'" 684 " error=%d", name, error); 685 } else { 686 module_error("Cannot load kernel object `%s'" 687 " error=%d", name, error); 688 } 689 return error; 690 } 691 TAILQ_INSERT_TAIL(&pending, mod, mod_chain); 692 mod->mod_source = MODULE_SOURCE_FILESYS; 693 error = module_fetch_info(mod); 694 if (error != 0) { 695 module_error("cannot fetch module info for `%s'", 696 name); 697 goto fail; 698 } 699 } 700 701 /* 702 * Check compatibility. 703 */ 704 mi = mod->mod_info; 705 if (strlen(mi->mi_name) >= MAXMODNAME) { 706 error = EINVAL; 707 module_error("module name `%s' too long", mi->mi_name); 708 goto fail; 709 } 710 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 711 module_error("module built for `%d', system `%d'", 712 mi->mi_version, __NetBSD_Version__); 713 if ((flags & MODCTL_LOAD_FORCE) != 0) { 714 module_error("forced load, system may be unstable"); 715 } else { 716 error = EPROGMISMATCH; 717 goto fail; 718 } 719 } 720 721 /* 722 * If a specific kind of module was requested, ensure that we have 723 * a match. 724 */ 725 if (class != MODULE_CLASS_ANY && class != mi->mi_class) { 726 module_print("incompatible module class for `%s' (%d != %d)", 727 name, class, mi->mi_class); 728 error = ENOENT; 729 goto fail; 730 } 731 732 /* 733 * If loading a dependency, `name' is a plain module name. 734 * The name must match. 735 */ 736 if (isdep && strcmp(mi->mi_name, name) != 0) { 737 module_error("dependency name mismatch (`%s' != `%s')", 738 name, mi->mi_name); 739 error = ENOENT; 740 goto fail; 741 } 742 743 /* 744 * Check to see if the module is already loaded. If so, we may 745 * have been recursively called to handle a dependency, so be sure 746 * to set modp. 747 */ 748 if ((mod2 = module_lookup(mi->mi_name)) != NULL) { 749 if (modp != NULL) 750 *modp = mod2; 751 module_print("module `%s' already loaded", mi->mi_name); 752 error = EEXIST; 753 goto fail; 754 } 755 756 /* 757 * Block circular dependencies. 758 */ 759 TAILQ_FOREACH(mod2, &pending, mod_chain) { 760 if (mod == mod2) { 761 continue; 762 } 763 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 764 error = EDEADLK; 765 module_error("circular dependency detected for `%s'", 766 mi->mi_name); 767 goto fail; 768 } 769 } 770 771 /* 772 * Now try to load any requisite modules. 773 */ 774 if (mi->mi_required != NULL) { 775 for (s = mi->mi_required; *s != '\0'; s = p) { 776 if (*s == ',') 777 s++; 778 p = s; 779 while (*p != '\0' && *p != ',') 780 p++; 781 len = p - s + 1; 782 if (len >= MAXMODNAME) { 783 error = EINVAL; 784 module_error("required module name `%s'" 785 " too long", mi->mi_required); 786 goto fail; 787 } 788 strlcpy(buf, s, len); 789 if (buf[0] == '\0') 790 break; 791 if (mod->mod_nrequired == MAXMODDEPS - 1) { 792 error = EINVAL; 793 module_error("too many required modules (%d)", 794 mod->mod_nrequired); 795 goto fail; 796 } 797 if (strcmp(buf, mi->mi_name) == 0) { 798 error = EDEADLK; 799 module_error("self-dependency detected for " 800 "`%s'", mi->mi_name); 801 goto fail; 802 } 803 error = module_do_load(buf, true, flags, NULL, 804 &mod->mod_required[mod->mod_nrequired++], 805 MODULE_CLASS_ANY, true); 806 if (error != 0) 807 goto fail; 808 } 809 } 810 811 /* 812 * We loaded all needed modules successfully: perform global 813 * relocations and initialize. 814 */ 815 error = kobj_affix(mod->mod_kobj, mi->mi_name); 816 if (error != 0) { 817 /* Cannot touch 'mi' as the module is now gone. */ 818 module_error("unable to affix module `%s'", name); 819 goto fail2; 820 } 821 822 /* 823 * Load and process <module>.prop if it exists. 824 */ 825 if (((flags & MODCTL_NO_PROP) == 0) && 826 (mod->mod_source == MODULE_SOURCE_FILESYS)) { 827 error = module_load_plist_file(path, nochroot, &plist, 828 &plistlen); 829 if (error != 0) { 830 module_print("plist load returned error %d for `%s'", 831 error, path); 832 } else { 833 filedict = prop_dictionary_internalize(plist); 834 if (filedict == NULL) { 835 error = EINVAL; 836 } else if (!module_merge_dicts(filedict, props)) { 837 error = EINVAL; 838 prop_object_release(filedict); 839 filedict = NULL; 840 } 841 } 842 if (plist != NULL) { 843 kmem_free(plist, PAGE_SIZE); 844 } 845 if ((error != 0) && (error != ENOENT)) { 846 goto fail; 847 } 848 } 849 850 KASSERT(module_active == NULL); 851 module_active = mod; 852 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, (filedict != NULL) ? 853 filedict : props); /* props will have been merged with filedict */ 854 module_active = NULL; 855 if (filedict != NULL) { 856 prop_object_release(filedict); 857 } 858 if (error != 0) { 859 module_error("modcmd function returned error %d for `%s'", 860 error, mi->mi_name); 861 goto fail; 862 } 863 if (mi->mi_class == MODULE_CLASS_SECMODEL) 864 secmodel_register(); 865 866 /* 867 * Good, the module loaded successfully. Put it onto the 868 * list and add references to its requisite modules. 869 */ 870 TAILQ_REMOVE(&pending, mod, mod_chain); 871 module_enqueue(mod); 872 if (modp != NULL) { 873 *modp = mod; 874 } 875 if (autoload) { 876 /* 877 * Arrange to try unloading the module after 878 * a short delay. 879 */ 880 mod->mod_autotime = time_second + module_autotime; 881 module_thread_kick(); 882 } 883 depth--; 884 if (path != NULL) 885 PNBUF_PUT(path); 886 return 0; 887 888 fail: 889 kobj_unload(mod->mod_kobj); 890 fail2: 891 TAILQ_REMOVE(&pending, mod, mod_chain); 892 kmem_free(mod, sizeof(*mod)); 893 depth--; 894 if (path != NULL) 895 PNBUF_PUT(path); 896 return error; 897 } 898 899 /* 900 * module_do_unload: 901 * 902 * Helper routine: do the dirty work of unloading a module. 903 */ 904 static int 905 module_do_unload(const char *name) 906 { 907 module_t *mod; 908 int error; 909 u_int i; 910 911 KASSERT(mutex_owned(&module_lock)); 912 913 mod = module_lookup(name); 914 if (mod == NULL) { 915 module_error("module `%s' not found", name); 916 return ENOENT; 917 } 918 if (mod->mod_refcnt != 0 || mod->mod_source == MODULE_SOURCE_KERNEL) { 919 module_print("module `%s' busy", name); 920 return EBUSY; 921 } 922 KASSERT(module_active == NULL); 923 module_active = mod; 924 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 925 module_active = NULL; 926 if (error != 0) { 927 module_print("cannot unload module `%s' error=%d", name, 928 error); 929 return error; 930 } 931 if (mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) 932 secmodel_deregister(); 933 module_count--; 934 TAILQ_REMOVE(&module_list, mod, mod_chain); 935 for (i = 0; i < mod->mod_nrequired; i++) { 936 mod->mod_required[i]->mod_refcnt--; 937 } 938 if (mod->mod_kobj != NULL) { 939 kobj_unload(mod->mod_kobj); 940 } 941 kmem_free(mod, sizeof(*mod)); 942 module_gen++; 943 944 return 0; 945 } 946 947 /* 948 * module_prime: 949 * 950 * Push a module loaded by the bootloader onto our internal 951 * list. 952 */ 953 int 954 module_prime(void *base, size_t size) 955 { 956 module_t *mod; 957 int error; 958 959 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 960 if (mod == NULL) { 961 return ENOMEM; 962 } 963 mod->mod_source = MODULE_SOURCE_BOOT; 964 965 error = kobj_load_mem(&mod->mod_kobj, base, size); 966 if (error != 0) { 967 kmem_free(mod, sizeof(*mod)); 968 module_error("unable to load object pushed by boot loader"); 969 return error; 970 } 971 error = module_fetch_info(mod); 972 if (error != 0) { 973 kobj_unload(mod->mod_kobj); 974 kmem_free(mod, sizeof(*mod)); 975 module_error("unable to load object pushed by boot loader"); 976 return error; 977 } 978 979 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 980 981 return 0; 982 } 983 984 /* 985 * module_fetch_into: 986 * 987 * Fetch modinfo record from a loaded module. 988 */ 989 static int 990 module_fetch_info(module_t *mod) 991 { 992 int error; 993 void *addr; 994 size_t size; 995 996 /* 997 * Find module info record and check compatibility. 998 */ 999 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1000 &addr, &size); 1001 if (error != 0) { 1002 module_error("`link_set_modules' section not present"); 1003 return error; 1004 } 1005 if (size != sizeof(modinfo_t **)) { 1006 module_error("`link_set_modules' section wrong size"); 1007 return error; 1008 } 1009 mod->mod_info = *(modinfo_t **)addr; 1010 1011 return 0; 1012 } 1013 1014 /* 1015 * module_find_section: 1016 * 1017 * Allows a module that is being initialized to look up a section 1018 * within its ELF object. 1019 */ 1020 int 1021 module_find_section(const char *name, void **addr, size_t *size) 1022 { 1023 1024 KASSERT(mutex_owned(&module_lock)); 1025 KASSERT(module_active != NULL); 1026 1027 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1028 } 1029 1030 /* 1031 * module_thread: 1032 * 1033 * Automatically unload modules. We try once to unload autoloaded 1034 * modules after module_autotime seconds. If the system is under 1035 * severe memory pressure, we'll try unloading all modules. 1036 */ 1037 static void 1038 module_thread(void *cookie) 1039 { 1040 module_t *mod, *next; 1041 modinfo_t *mi; 1042 int error; 1043 1044 for (;;) { 1045 mutex_enter(&module_lock); 1046 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1047 next = TAILQ_NEXT(mod, mod_chain); 1048 if (uvmexp.free < uvmexp.freemin) { 1049 module_thread_ticks = hz; 1050 } else if (mod->mod_autotime == 0) { 1051 continue; 1052 } else if (time_second < mod->mod_autotime) { 1053 module_thread_ticks = hz; 1054 continue; 1055 } else { 1056 mod->mod_autotime = 0; 1057 } 1058 /* 1059 * If this module wants to avoid autounload then 1060 * skip it. Some modules can ping-pong in and out 1061 * because their use is transient but often. 1062 * Example: exec_script. 1063 */ 1064 mi = mod->mod_info; 1065 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1066 if (error == 0 || error == ENOTTY) { 1067 (void)module_do_unload(mi->mi_name); 1068 } 1069 } 1070 mutex_exit(&module_lock); 1071 1072 mutex_enter(&module_thread_lock); 1073 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1074 module_thread_ticks); 1075 module_thread_ticks = 0; 1076 mutex_exit(&module_thread_lock); 1077 } 1078 } 1079 1080 /* 1081 * module_thread: 1082 * 1083 * Kick the module thread into action, perhaps because the 1084 * system is low on memory. 1085 */ 1086 void 1087 module_thread_kick(void) 1088 { 1089 1090 mutex_enter(&module_thread_lock); 1091 module_thread_ticks = hz; 1092 cv_broadcast(&module_thread_cv); 1093 mutex_exit(&module_thread_lock); 1094 } 1095 1096 #ifdef DDB 1097 /* 1098 * module_whatis: 1099 * 1100 * Helper routine for DDB. 1101 */ 1102 void 1103 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1104 { 1105 module_t *mod; 1106 size_t msize; 1107 vaddr_t maddr; 1108 1109 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1110 if (mod->mod_kobj == NULL) { 1111 continue; 1112 } 1113 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1114 continue; 1115 if (addr < maddr || addr >= maddr + msize) { 1116 continue; 1117 } 1118 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1119 (void *)addr, (void *)maddr, 1120 (size_t)(addr - maddr), mod->mod_info->mi_name); 1121 } 1122 } 1123 1124 /* 1125 * module_print_list: 1126 * 1127 * Helper routine for DDB. 1128 */ 1129 void 1130 module_print_list(void (*pr)(const char *, ...)) 1131 { 1132 const char *src; 1133 module_t *mod; 1134 size_t msize; 1135 vaddr_t maddr; 1136 1137 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1138 1139 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1140 switch (mod->mod_source) { 1141 case MODULE_SOURCE_KERNEL: 1142 src = "builtin"; 1143 break; 1144 case MODULE_SOURCE_FILESYS: 1145 src = "filesys"; 1146 break; 1147 case MODULE_SOURCE_BOOT: 1148 src = "boot"; 1149 break; 1150 default: 1151 src = "unknown"; 1152 break; 1153 } 1154 if (mod->mod_kobj == NULL) { 1155 maddr = 0; 1156 msize = 0; 1157 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1158 continue; 1159 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1160 (long)maddr, (long)msize, src); 1161 } 1162 } 1163 #endif /* DDB */ 1164 1165 /* 1166 * module_load_plist_file: 1167 * 1168 * Load a plist located in the file system into memory. 1169 */ 1170 static int 1171 module_load_plist_file(const char *modpath, const bool nochroot, 1172 void **basep, size_t *length) 1173 { 1174 struct nameidata nd; 1175 struct stat sb; 1176 void *base; 1177 char *proppath; 1178 size_t resid; 1179 int error, pathlen; 1180 1181 base = NULL; 1182 *length = 0; 1183 1184 proppath = PNBUF_GET(); 1185 strcpy(proppath, modpath); 1186 pathlen = strlen(proppath); 1187 if ((pathlen >= 5) && (strcmp(&proppath[pathlen - 5], ".kmod") == 0)) { 1188 strcpy(&proppath[pathlen - 5], ".prop"); 1189 } else if (pathlen < MAXPATHLEN - 5) { 1190 strcat(proppath, ".prop"); 1191 } else { 1192 error = ENOENT; 1193 goto out1; 1194 } 1195 1196 NDINIT(&nd, LOOKUP, FOLLOW | (nochroot ? NOCHROOT : 0), 1197 UIO_SYSSPACE, proppath); 1198 1199 error = namei(&nd); 1200 if (error != 0) { 1201 goto out1; 1202 } 1203 1204 error = vn_stat(nd.ni_vp, &sb); 1205 if (sb.st_size >= (PAGE_SIZE - 1)) { /* leave space for term \0 */ 1206 error = EINVAL; 1207 } 1208 if (error != 0) { 1209 goto out1; 1210 } 1211 1212 error = vn_open(&nd, FREAD, 0); 1213 if (error != 0) { 1214 goto out1; 1215 } 1216 1217 base = kmem_alloc(PAGE_SIZE, KM_SLEEP); 1218 if (base == NULL) { 1219 error = ENOMEM; 1220 goto out; 1221 } 1222 1223 error = vn_rdwr(UIO_READ, nd.ni_vp, base, sb.st_size, 0, 1224 UIO_SYSSPACE, IO_NODELOCKED, curlwp->l_cred, &resid, curlwp); 1225 *((uint8_t *)base + sb.st_size) = '\0'; 1226 if (error == 0 && resid != 0) { 1227 error = EINVAL; 1228 } 1229 if (error != 0) { 1230 kmem_free(base, PAGE_SIZE); 1231 base = NULL; 1232 } 1233 *length = sb.st_size; 1234 1235 out: 1236 VOP_UNLOCK(nd.ni_vp, 0); 1237 vn_close(nd.ni_vp, FREAD, kauth_cred_get()); 1238 1239 out1: 1240 PNBUF_PUT(proppath); 1241 *basep = base; 1242 return error; 1243 } 1244 1245 static bool 1246 module_merge_dicts(prop_dictionary_t existing_dict, 1247 const prop_dictionary_t new_dict) 1248 { 1249 prop_dictionary_keysym_t props_keysym; 1250 prop_object_iterator_t props_iter; 1251 prop_object_t props_obj; 1252 const char *props_key; 1253 bool error; 1254 1255 error = false; 1256 props_iter = prop_dictionary_iterator(new_dict); 1257 if (props_iter == NULL) { 1258 return false; 1259 } 1260 1261 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1262 props_keysym = (prop_dictionary_keysym_t)props_obj; 1263 props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); 1264 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1265 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1266 props_key, props_obj)) { 1267 error = true; 1268 goto out; 1269 } 1270 } 1271 error = false; 1272 1273 out: 1274 prop_object_iterator_release(props_iter); 1275 1276 return !error; 1277 } 1278