1 /* $NetBSD: kern_module.c,v 1.159 2022/09/06 13:31:09 pgoyette 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 1.159 2022/09/06 13:31:09 pgoyette Exp $"); 38 39 #define _MODULE_INTERNAL 40 41 #ifdef _KERNEL_OPT 42 #include "opt_ddb.h" 43 #include "opt_modular.h" 44 #endif 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/kernel.h> 49 #include <sys/proc.h> 50 #include <sys/lwp.h> 51 #include <sys/kauth.h> 52 #include <sys/kobj.h> 53 #include <sys/kmem.h> 54 #include <sys/module.h> 55 #include <sys/module_hook.h> 56 #include <sys/kthread.h> 57 #include <sys/sysctl.h> 58 #include <sys/lock.h> 59 #include <sys/evcnt.h> 60 61 #include <uvm/uvm_extern.h> 62 63 struct vm_map *module_map; 64 const char *module_machine; 65 char module_base[MODULE_BASE_SIZE]; 66 67 struct modlist module_list = TAILQ_HEAD_INITIALIZER(module_list); 68 struct modlist module_builtins = TAILQ_HEAD_INITIALIZER(module_builtins); 69 static struct modlist module_bootlist = TAILQ_HEAD_INITIALIZER(module_bootlist); 70 71 struct module_callbacks { 72 TAILQ_ENTRY(module_callbacks) modcb_list; 73 void (*modcb_load)(struct module *); 74 void (*modcb_unload)(struct module *); 75 }; 76 TAILQ_HEAD(modcblist, module_callbacks); 77 static struct modcblist modcblist; 78 79 static module_t *module_netbsd; 80 static const modinfo_t module_netbsd_modinfo = { 81 .mi_version = __NetBSD_Version__, 82 .mi_class = MODULE_CLASS_MISC, 83 .mi_name = "netbsd" 84 }; 85 86 static module_t *module_active; 87 #ifdef MODULAR_DEFAULT_VERBOSE 88 bool module_verbose_on = true; 89 #else 90 bool module_verbose_on = false; 91 #endif 92 #ifdef MODULAR_DEFAULT_AUTOLOAD 93 bool module_autoload_on = true; 94 #else 95 bool module_autoload_on = false; 96 #endif 97 bool module_autounload_unsafe = 0; 98 u_int module_count; 99 u_int module_builtinlist; 100 u_int module_autotime = 10; 101 u_int module_gen = 1; 102 static kcondvar_t module_thread_cv; 103 static kmutex_t module_thread_lock; 104 static int module_thread_ticks; 105 int (*module_load_vfs_vec)(const char *, int, bool, module_t *, 106 prop_dictionary_t *) = (void *)eopnotsupp; 107 108 static kauth_listener_t module_listener; 109 110 static specificdata_domain_t module_specificdata_domain; 111 112 /* Ensure that the kernel's link set isn't empty. */ 113 static modinfo_t module_dummy; 114 __link_set_add_rodata(modules, module_dummy); 115 116 static module_t *module_newmodule(modsrc_t); 117 static void module_free(module_t *); 118 static void module_require_force(module_t *); 119 static int module_do_load(const char *, bool, int, prop_dictionary_t, 120 module_t **, modclass_t modclass, bool); 121 static int module_do_unload(const char *, bool); 122 static int module_do_builtin(const module_t *, const char *, module_t **, 123 prop_dictionary_t); 124 static int module_fetch_info(module_t *); 125 static void module_thread(void *); 126 127 static module_t *module_lookup(const char *); 128 static void module_enqueue(module_t *); 129 130 static bool module_merge_dicts(prop_dictionary_t, const prop_dictionary_t); 131 132 static void sysctl_module_setup(void); 133 static int sysctl_module_autotime(SYSCTLFN_PROTO); 134 135 static void module_callback_load(struct module *); 136 static void module_callback_unload(struct module *); 137 138 #define MODULE_CLASS_MATCH(mi, modclass) \ 139 ((modclass) == MODULE_CLASS_ANY || (modclass) == (mi)->mi_class) 140 141 static void 142 module_incompat(const modinfo_t *mi, int modclass) 143 { 144 module_error("incompatible module class %d for `%s' (wanted %d)", 145 mi->mi_class, mi->mi_name, modclass); 146 } 147 148 struct module * 149 module_kernel(void) 150 { 151 152 return module_netbsd; 153 } 154 155 /* 156 * module_error: 157 * 158 * Utility function: log an error. 159 */ 160 void 161 module_error(const char *fmt, ...) 162 { 163 va_list ap; 164 165 va_start(ap, fmt); 166 printf("WARNING: module error: "); 167 vprintf(fmt, ap); 168 printf("\n"); 169 va_end(ap); 170 } 171 172 /* 173 * module_print: 174 * 175 * Utility function: log verbose output. 176 */ 177 void 178 module_print(const char *fmt, ...) 179 { 180 va_list ap; 181 182 if (module_verbose_on) { 183 va_start(ap, fmt); 184 printf("DEBUG: module: "); 185 vprintf(fmt, ap); 186 printf("\n"); 187 va_end(ap); 188 } 189 } 190 191 /* 192 * module_name: 193 * 194 * Utility function: return the module's name. 195 */ 196 const char * 197 module_name(struct module *mod) 198 { 199 200 return mod->mod_info->mi_name; 201 } 202 203 /* 204 * module_source: 205 * 206 * Utility function: return the module's source. 207 */ 208 modsrc_t 209 module_source(struct module *mod) 210 { 211 212 return mod->mod_source; 213 } 214 215 static int 216 module_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 217 void *arg0, void *arg1, void *arg2, void *arg3) 218 { 219 int result; 220 221 result = KAUTH_RESULT_DEFER; 222 223 if (action != KAUTH_SYSTEM_MODULE) 224 return result; 225 226 if ((uintptr_t)arg2 != 0) /* autoload */ 227 result = KAUTH_RESULT_ALLOW; 228 229 return result; 230 } 231 232 /* 233 * Allocate a new module_t 234 */ 235 static module_t * 236 module_newmodule(modsrc_t source) 237 { 238 module_t *mod; 239 240 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 241 mod->mod_source = source; 242 specificdata_init(module_specificdata_domain, &mod->mod_sdref); 243 return mod; 244 } 245 246 /* 247 * Free a module_t 248 */ 249 static void 250 module_free(module_t *mod) 251 { 252 253 specificdata_fini(module_specificdata_domain, &mod->mod_sdref); 254 if (mod->mod_required) 255 kmem_free(mod->mod_required, mod->mod_arequired * 256 sizeof(module_t *)); 257 kmem_free(mod, sizeof(*mod)); 258 } 259 260 /* 261 * Require the -f (force) flag to load a module 262 */ 263 static void 264 module_require_force(struct module *mod) 265 { 266 SET(mod->mod_flags, MODFLG_MUST_FORCE); 267 } 268 269 /* 270 * Add modules to the builtin list. This can done at boottime or 271 * at runtime if the module is linked into the kernel with an 272 * external linker. All or none of the input will be handled. 273 * Optionally, the modules can be initialized. If they are not 274 * initialized, module_init_class() or module_load() can be used 275 * later, but these are not guaranteed to give atomic results. 276 */ 277 int 278 module_builtin_add(modinfo_t *const *mip, size_t nmodinfo, bool init) 279 { 280 struct module **modp = NULL, *mod_iter; 281 int rv = 0, i, mipskip; 282 283 if (init) { 284 rv = kauth_authorize_system(kauth_cred_get(), 285 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, 286 (void *)(uintptr_t)1, NULL); 287 if (rv) { 288 return rv; 289 } 290 } 291 292 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 293 if (mip[i] == &module_dummy) { 294 KASSERT(nmodinfo > 0); 295 nmodinfo--; 296 } 297 } 298 if (nmodinfo == 0) 299 return 0; 300 301 modp = kmem_zalloc(sizeof(*modp) * nmodinfo, KM_SLEEP); 302 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 303 if (mip[i+mipskip] == &module_dummy) { 304 mipskip++; 305 continue; 306 } 307 modp[i] = module_newmodule(MODULE_SOURCE_KERNEL); 308 modp[i]->mod_info = mip[i+mipskip]; 309 } 310 kernconfig_lock(); 311 312 /* do this in three stages for error recovery and atomicity */ 313 314 /* first check for presence */ 315 for (i = 0; i < nmodinfo; i++) { 316 TAILQ_FOREACH(mod_iter, &module_builtins, mod_chain) { 317 if (strcmp(mod_iter->mod_info->mi_name, 318 modp[i]->mod_info->mi_name) == 0) 319 break; 320 } 321 if (mod_iter) { 322 rv = EEXIST; 323 goto out; 324 } 325 326 if (module_lookup(modp[i]->mod_info->mi_name) != NULL) { 327 rv = EEXIST; 328 goto out; 329 } 330 } 331 332 /* then add to list */ 333 for (i = 0; i < nmodinfo; i++) { 334 TAILQ_INSERT_TAIL(&module_builtins, modp[i], mod_chain); 335 module_builtinlist++; 336 } 337 338 /* finally, init (if required) */ 339 if (init) { 340 for (i = 0; i < nmodinfo; i++) { 341 rv = module_do_builtin(modp[i], 342 modp[i]->mod_info->mi_name, NULL, NULL); 343 /* throw in the towel, recovery hard & not worth it */ 344 if (rv) 345 panic("%s: builtin module \"%s\" init failed:" 346 " %d", __func__, 347 modp[i]->mod_info->mi_name, rv); 348 } 349 } 350 351 out: 352 kernconfig_unlock(); 353 if (rv != 0) { 354 for (i = 0; i < nmodinfo; i++) { 355 if (modp[i]) 356 module_free(modp[i]); 357 } 358 } 359 kmem_free(modp, sizeof(*modp) * nmodinfo); 360 return rv; 361 } 362 363 /* 364 * Optionally fini and remove builtin module from the kernel. 365 * Note: the module will now be unreachable except via mi && builtin_add. 366 */ 367 int 368 module_builtin_remove(modinfo_t *mi, bool fini) 369 { 370 struct module *mod; 371 int rv = 0; 372 373 if (fini) { 374 rv = kauth_authorize_system(kauth_cred_get(), 375 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_UNLOAD, 376 NULL, NULL); 377 if (rv) 378 return rv; 379 380 kernconfig_lock(); 381 rv = module_do_unload(mi->mi_name, true); 382 if (rv) { 383 goto out; 384 } 385 } else { 386 kernconfig_lock(); 387 } 388 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 389 if (strcmp(mod->mod_info->mi_name, mi->mi_name) == 0) 390 break; 391 } 392 if (mod) { 393 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 394 module_builtinlist--; 395 } else { 396 KASSERT(fini == false); 397 rv = ENOENT; 398 } 399 400 out: 401 kernconfig_unlock(); 402 return rv; 403 } 404 405 /* 406 * module_init: 407 * 408 * Initialize the module subsystem. 409 */ 410 void 411 module_init(void) 412 { 413 __link_set_decl(modules, modinfo_t); 414 extern struct vm_map *module_map; 415 modinfo_t *const *mip; 416 int rv; 417 418 if (module_map == NULL) { 419 module_map = kernel_map; 420 } 421 cv_init(&module_thread_cv, "mod_unld"); 422 mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE); 423 TAILQ_INIT(&modcblist); 424 425 #ifdef MODULAR /* XXX */ 426 module_init_md(); 427 #endif 428 429 #ifdef KERNEL_DIR 430 const char *booted_kernel = get_booted_kernel(); 431 if (booted_kernel) { 432 char *ptr = strrchr(booted_kernel, '/'); 433 snprintf(module_base, sizeof(module_base), "/%.*s/modules", 434 (int)(ptr - booted_kernel), booted_kernel); 435 } else { 436 strlcpy(module_base, "/netbsd/modules", sizeof(module_base)); 437 printf("Cannot find kernel name, loading modules from \"%s\"\n", 438 module_base); 439 } 440 #else 441 if (!module_machine) 442 module_machine = machine; 443 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 444 snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules", 445 module_machine, osrelease); 446 #else /* release */ 447 snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules", 448 module_machine, __NetBSD_Version__ / 100000000, 449 __NetBSD_Version__ / 1000000 % 100); 450 #endif 451 #endif 452 453 module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM, 454 module_listener_cb, NULL); 455 456 __link_set_foreach(mip, modules) { 457 if ((rv = module_builtin_add(mip, 1, false)) != 0) 458 module_error("builtin %s failed: %d\n", 459 (*mip)->mi_name, rv); 460 } 461 462 sysctl_module_setup(); 463 module_specificdata_domain = specificdata_domain_create(); 464 465 module_netbsd = module_newmodule(MODULE_SOURCE_KERNEL); 466 module_netbsd->mod_refcnt = 1; 467 module_netbsd->mod_info = &module_netbsd_modinfo; 468 } 469 470 /* 471 * module_start_unload_thread: 472 * 473 * Start the auto unload kthread. 474 */ 475 void 476 module_start_unload_thread(void) 477 { 478 int error; 479 480 error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread, 481 NULL, NULL, "modunload"); 482 if (error != 0) 483 panic("%s: %d", __func__, error); 484 } 485 486 /* 487 * module_builtin_require_force 488 * 489 * Require MODCTL_MUST_FORCE to load any built-in modules that have 490 * not yet been initialized 491 */ 492 void 493 module_builtin_require_force(void) 494 { 495 module_t *mod; 496 497 kernconfig_lock(); 498 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 499 module_require_force(mod); 500 } 501 kernconfig_unlock(); 502 } 503 504 static struct sysctllog *module_sysctllog; 505 506 static int 507 sysctl_module_autotime(SYSCTLFN_ARGS) 508 { 509 struct sysctlnode node; 510 int t, error; 511 512 t = *(int *)rnode->sysctl_data; 513 514 node = *rnode; 515 node.sysctl_data = &t; 516 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 517 if (error || newp == NULL) 518 return (error); 519 520 if (t < 0) 521 return (EINVAL); 522 523 *(int *)rnode->sysctl_data = t; 524 return (0); 525 } 526 527 static void 528 sysctl_module_setup(void) 529 { 530 const struct sysctlnode *node = NULL; 531 532 sysctl_createv(&module_sysctllog, 0, NULL, &node, 533 CTLFLAG_PERMANENT, 534 CTLTYPE_NODE, "module", 535 SYSCTL_DESCR("Module options"), 536 NULL, 0, NULL, 0, 537 CTL_KERN, CTL_CREATE, CTL_EOL); 538 539 if (node == NULL) 540 return; 541 542 sysctl_createv(&module_sysctllog, 0, &node, NULL, 543 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 544 CTLTYPE_BOOL, "autoload", 545 SYSCTL_DESCR("Enable automatic load of modules"), 546 NULL, 0, &module_autoload_on, 0, 547 CTL_CREATE, CTL_EOL); 548 sysctl_createv(&module_sysctllog, 0, &node, NULL, 549 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 550 CTLTYPE_BOOL, "autounload_unsafe", 551 SYSCTL_DESCR("Enable automatic unload of unaudited modules"), 552 NULL, 0, &module_autounload_unsafe, 0, 553 CTL_CREATE, CTL_EOL); 554 sysctl_createv(&module_sysctllog, 0, &node, NULL, 555 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 556 CTLTYPE_BOOL, "verbose", 557 SYSCTL_DESCR("Enable verbose output"), 558 NULL, 0, &module_verbose_on, 0, 559 CTL_CREATE, CTL_EOL); 560 sysctl_createv(&module_sysctllog, 0, &node, NULL, 561 CTLFLAG_PERMANENT | CTLFLAG_READONLY, 562 CTLTYPE_STRING, "path", 563 SYSCTL_DESCR("Default module load path"), 564 NULL, 0, module_base, 0, 565 CTL_CREATE, CTL_EOL); 566 sysctl_createv(&module_sysctllog, 0, &node, NULL, 567 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 568 CTLTYPE_INT, "autotime", 569 SYSCTL_DESCR("Auto-unload delay"), 570 sysctl_module_autotime, 0, &module_autotime, 0, 571 CTL_CREATE, CTL_EOL); 572 } 573 574 /* 575 * module_init_class: 576 * 577 * Initialize all built-in and pre-loaded modules of the 578 * specified class. 579 */ 580 void 581 module_init_class(modclass_t modclass) 582 { 583 TAILQ_HEAD(, module) bi_fail = TAILQ_HEAD_INITIALIZER(bi_fail); 584 module_t *mod; 585 modinfo_t *mi; 586 587 kernconfig_lock(); 588 /* 589 * Builtins first. These will not depend on pre-loaded modules 590 * (because the kernel would not link). 591 */ 592 do { 593 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 594 mi = mod->mod_info; 595 if (!MODULE_CLASS_MATCH(mi, modclass)) 596 continue; 597 /* 598 * If initializing a builtin module fails, don't try 599 * to load it again. But keep it around and queue it 600 * on the builtins list after we're done with module 601 * init. Don't set it to MODFLG_MUST_FORCE in case a 602 * future attempt to initialize can be successful. 603 * (If the module has previously been set to 604 * MODFLG_MUST_FORCE, don't try to override that!) 605 */ 606 if (ISSET(mod->mod_flags, MODFLG_MUST_FORCE) || 607 module_do_builtin(mod, mi->mi_name, NULL, 608 NULL) != 0) { 609 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 610 TAILQ_INSERT_TAIL(&bi_fail, mod, mod_chain); 611 } 612 break; 613 } 614 } while (mod != NULL); 615 616 /* 617 * Now preloaded modules. These will be pulled off the 618 * list as we call module_do_load(); 619 */ 620 do { 621 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 622 mi = mod->mod_info; 623 if (!MODULE_CLASS_MATCH(mi, modclass)) 624 continue; 625 module_do_load(mi->mi_name, false, 0, NULL, NULL, 626 modclass, false); 627 break; 628 } 629 } while (mod != NULL); 630 631 /* return failed builtin modules to builtin list */ 632 while ((mod = TAILQ_FIRST(&bi_fail)) != NULL) { 633 TAILQ_REMOVE(&bi_fail, mod, mod_chain); 634 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 635 } 636 637 kernconfig_unlock(); 638 } 639 640 /* 641 * module_compatible: 642 * 643 * Return true if the two supplied kernel versions are said to 644 * have the same binary interface for kernel code. The entire 645 * version is signficant for the development tree (-current), 646 * major and minor versions are significant for official 647 * releases of the system. 648 */ 649 bool 650 module_compatible(int v1, int v2) 651 { 652 653 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 654 return v1 == v2; 655 #else /* release */ 656 return abs(v1 - v2) < 10000; 657 #endif 658 } 659 660 /* 661 * module_load: 662 * 663 * Load a single module from the file system. 664 */ 665 int 666 module_load(const char *filename, int flags, prop_dictionary_t props, 667 modclass_t modclass) 668 { 669 module_t *mod; 670 int error; 671 672 /* Test if we already have the module loaded before 673 * authorizing so we have the opportunity to return EEXIST. */ 674 kernconfig_lock(); 675 mod = module_lookup(filename); 676 if (mod != NULL) { 677 module_print("%s module `%s' already loaded", 678 "requested", filename); 679 error = EEXIST; 680 goto out; 681 } 682 683 /* Authorize. */ 684 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 685 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 686 if (error != 0) 687 goto out; 688 689 error = module_do_load(filename, false, flags, props, NULL, modclass, 690 false); 691 692 out: 693 kernconfig_unlock(); 694 return error; 695 } 696 697 /* 698 * module_autoload: 699 * 700 * Load a single module from the file system, system initiated. 701 */ 702 int 703 module_autoload(const char *filename, modclass_t modclass) 704 { 705 int error; 706 struct proc *p = curlwp->l_proc; 707 708 kernconfig_lock(); 709 710 /* Nothing if the user has disabled it. */ 711 if (!module_autoload_on) { 712 kernconfig_unlock(); 713 return EPERM; 714 } 715 716 /* Disallow path separators and magic symlinks. */ 717 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 718 strchr(filename, '.') != NULL) { 719 kernconfig_unlock(); 720 return EPERM; 721 } 722 723 /* Authorize. */ 724 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 725 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 726 727 if (error == 0) 728 error = module_do_load(filename, false, 0, NULL, NULL, modclass, 729 true); 730 731 module_print("Autoload for `%s' requested by pid %d (%s), status %d", 732 filename, p->p_pid, p->p_comm, error); 733 kernconfig_unlock(); 734 return error; 735 } 736 737 /* 738 * module_unload: 739 * 740 * Find and unload a module by name. 741 */ 742 int 743 module_unload(const char *name) 744 { 745 int error; 746 747 /* Authorize. */ 748 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 749 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 750 if (error != 0) { 751 return error; 752 } 753 754 kernconfig_lock(); 755 error = module_do_unload(name, true); 756 kernconfig_unlock(); 757 758 return error; 759 } 760 761 /* 762 * module_lookup: 763 * 764 * Look up a module by name. 765 */ 766 module_t * 767 module_lookup(const char *name) 768 { 769 module_t *mod; 770 771 KASSERT(kernconfig_is_held()); 772 773 TAILQ_FOREACH(mod, &module_list, mod_chain) { 774 if (strcmp(mod->mod_info->mi_name, name) == 0) 775 break; 776 } 777 778 return mod; 779 } 780 781 /* 782 * module_hold: 783 * 784 * Add a single reference to a module. It's the caller's 785 * responsibility to ensure that the reference is dropped 786 * later. 787 */ 788 void 789 module_hold(module_t *mod) 790 { 791 792 kernconfig_lock(); 793 mod->mod_refcnt++; 794 kernconfig_unlock(); 795 } 796 797 /* 798 * module_rele: 799 * 800 * Release a reference acquired with module_hold(). 801 */ 802 void 803 module_rele(module_t *mod) 804 { 805 806 kernconfig_lock(); 807 KASSERT(mod->mod_refcnt > 0); 808 mod->mod_refcnt--; 809 kernconfig_unlock(); 810 } 811 812 /* 813 * module_enqueue: 814 * 815 * Put a module onto the global list and update counters. 816 */ 817 void 818 module_enqueue(module_t *mod) 819 { 820 int i; 821 822 KASSERT(kernconfig_is_held()); 823 824 /* 825 * Put new entry at the head of the queue so autounload can unload 826 * requisite modules with only one pass through the queue. 827 */ 828 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 829 if (mod->mod_nrequired) { 830 831 /* Add references to the requisite modules. */ 832 for (i = 0; i < mod->mod_nrequired; i++) { 833 KASSERT((*mod->mod_required)[i] != NULL); 834 (*mod->mod_required)[i]->mod_refcnt++; 835 } 836 } 837 module_count++; 838 module_gen++; 839 } 840 841 /* 842 * Our array of required module pointers starts with zero entries. If we 843 * need to add a new entry, and the list is already full, we reallocate a 844 * larger array, adding MAXMODDEPS entries. 845 */ 846 static void 847 alloc_required(module_t *mod) 848 { 849 module_t *(*new)[], *(*old)[]; 850 int areq; 851 int i; 852 853 if (mod->mod_nrequired >= mod->mod_arequired) { 854 areq = mod->mod_arequired + MAXMODDEPS; 855 old = mod->mod_required; 856 new = kmem_zalloc(areq * sizeof(module_t *), KM_SLEEP); 857 for (i = 0; i < mod->mod_arequired; i++) 858 (*new)[i] = (*old)[i]; 859 mod->mod_required = new; 860 if (old) 861 kmem_free(old, mod->mod_arequired * sizeof(module_t *)); 862 mod->mod_arequired = areq; 863 } 864 } 865 866 /* 867 * module_do_builtin: 868 * 869 * Initialize a module from the list of modules that are 870 * already linked into the kernel. 871 */ 872 static int 873 module_do_builtin(const module_t *pmod, const char *name, module_t **modp, 874 prop_dictionary_t props) 875 { 876 const char *p, *s; 877 char buf[MAXMODNAME]; 878 modinfo_t *mi = NULL; 879 module_t *mod, *mod2, *mod_loaded, *prev_active; 880 size_t len; 881 int error; 882 883 KASSERT(kernconfig_is_held()); 884 885 /* 886 * Search the list to see if we have a module by this name. 887 */ 888 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 889 if (strcmp(mod->mod_info->mi_name, name) == 0) { 890 mi = mod->mod_info; 891 break; 892 } 893 } 894 895 /* 896 * Check to see if already loaded. This might happen if we 897 * were already loaded as a dependency. 898 */ 899 if ((mod_loaded = module_lookup(name)) != NULL) { 900 KASSERT(mod == NULL); 901 if (modp) 902 *modp = mod_loaded; 903 return 0; 904 } 905 906 /* Note! This is from TAILQ, not immediate above */ 907 if (mi == NULL) { 908 /* 909 * XXX: We'd like to panic here, but currently in some 910 * cases (such as nfsserver + nfs), the dependee can be 911 * successfully linked without the dependencies. 912 */ 913 module_error("built-in module %s can't find builtin " 914 "dependency `%s'", pmod->mod_info->mi_name, name); 915 return ENOENT; 916 } 917 918 /* 919 * Initialize pre-requisites. 920 */ 921 KASSERT(mod->mod_required == NULL); 922 KASSERT(mod->mod_arequired == 0); 923 KASSERT(mod->mod_nrequired == 0); 924 if (mi->mi_required != NULL) { 925 for (s = mi->mi_required; *s != '\0'; s = p) { 926 if (*s == ',') 927 s++; 928 p = s; 929 while (*p != '\0' && *p != ',') 930 p++; 931 len = uimin(p - s + 1, sizeof(buf)); 932 strlcpy(buf, s, len); 933 if (buf[0] == '\0') 934 break; 935 alloc_required(mod); 936 error = module_do_builtin(mod, buf, &mod2, NULL); 937 if (error != 0) { 938 module_error("built-in module %s prerequisite " 939 "%s failed, error %d", name, buf, error); 940 goto fail; 941 } 942 (*mod->mod_required)[mod->mod_nrequired++] = mod2; 943 } 944 } 945 946 /* 947 * Try to initialize the module. 948 */ 949 prev_active = module_active; 950 module_active = mod; 951 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, props); 952 module_active = prev_active; 953 if (error != 0) { 954 module_error("built-in module %s failed its MODULE_CMD_INIT, " 955 "error %d", mi->mi_name, error); 956 goto fail; 957 } 958 959 /* load always succeeds after this point */ 960 961 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 962 module_builtinlist--; 963 if (modp != NULL) { 964 *modp = mod; 965 } 966 module_enqueue(mod); 967 return 0; 968 969 fail: 970 if (mod->mod_required) 971 kmem_free(mod->mod_required, mod->mod_arequired * 972 sizeof(module_t *)); 973 mod->mod_arequired = 0; 974 mod->mod_nrequired = 0; 975 mod->mod_required = NULL; 976 return error; 977 } 978 979 /* 980 * module_load_sysctl 981 * 982 * Check to see if a non-builtin module has any SYSCTL_SETUP() routine(s) 983 * registered. If so, call it (them). 984 */ 985 986 static void 987 module_load_sysctl(module_t *mod) 988 { 989 void (**ls_funcp)(struct sysctllog **); 990 void *ls_start; 991 size_t ls_size, count; 992 int error; 993 994 /* 995 * Built-in modules don't have a mod_kobj so we cannot search 996 * for their link_set_sysctl_funcs 997 */ 998 if (mod->mod_source == MODULE_SOURCE_KERNEL) 999 return; 1000 1001 error = kobj_find_section(mod->mod_kobj, "link_set_sysctl_funcs", 1002 &ls_start, &ls_size); 1003 if (error == 0) { 1004 count = ls_size / sizeof(ls_start); 1005 ls_funcp = ls_start; 1006 while (count--) { 1007 (**ls_funcp)(&mod->mod_sysctllog); 1008 ls_funcp++; 1009 } 1010 } 1011 } 1012 1013 /* 1014 * module_load_evcnt 1015 * 1016 * Check to see if a non-builtin module has any static evcnt's defined; 1017 * if so, attach them. 1018 */ 1019 1020 static void 1021 module_load_evcnt(module_t *mod) 1022 { 1023 struct evcnt * const *ls_evp; 1024 void *ls_start; 1025 size_t ls_size, count; 1026 int error; 1027 1028 /* 1029 * Built-in modules' static evcnt stuff will be handled 1030 * automatically as part of general kernel initialization 1031 */ 1032 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1033 return; 1034 1035 error = kobj_find_section(mod->mod_kobj, "link_set_evcnts", 1036 &ls_start, &ls_size); 1037 if (error == 0) { 1038 count = ls_size / sizeof(*ls_evp); 1039 ls_evp = ls_start; 1040 while (count--) { 1041 evcnt_attach_static(*ls_evp++); 1042 } 1043 } 1044 } 1045 1046 /* 1047 * module_unload_evcnt 1048 * 1049 * Check to see if a non-builtin module has any static evcnt's defined; 1050 * if so, detach them. 1051 */ 1052 1053 static void 1054 module_unload_evcnt(module_t *mod) 1055 { 1056 struct evcnt * const *ls_evp; 1057 void *ls_start; 1058 size_t ls_size, count; 1059 int error; 1060 1061 /* 1062 * Built-in modules' static evcnt stuff will be handled 1063 * automatically as part of general kernel initialization 1064 */ 1065 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1066 return; 1067 1068 error = kobj_find_section(mod->mod_kobj, "link_set_evcnts", 1069 &ls_start, &ls_size); 1070 if (error == 0) { 1071 count = ls_size / sizeof(*ls_evp); 1072 ls_evp = (void *)((char *)ls_start + ls_size); 1073 while (count--) { 1074 evcnt_detach(*--ls_evp); 1075 } 1076 } 1077 } 1078 1079 /* 1080 * module_do_load: 1081 * 1082 * Helper routine: load a module from the file system, or one 1083 * pushed by the boot loader. 1084 */ 1085 static int 1086 module_do_load(const char *name, bool isdep, int flags, 1087 prop_dictionary_t props, module_t **modp, modclass_t modclass, 1088 bool autoload) 1089 { 1090 /* The pending list for this level of recursion */ 1091 TAILQ_HEAD(pending_t, module); 1092 struct pending_t *pending; 1093 struct pending_t new_pending = TAILQ_HEAD_INITIALIZER(new_pending); 1094 1095 /* The stack of pending lists */ 1096 static SLIST_HEAD(pend_head, pend_entry) pend_stack = 1097 SLIST_HEAD_INITIALIZER(pend_stack); 1098 struct pend_entry { 1099 SLIST_ENTRY(pend_entry) pe_entry; 1100 struct pending_t *pe_pending; 1101 } my_pend_entry; 1102 1103 modinfo_t *mi; 1104 module_t *mod, *mod2, *prev_active; 1105 prop_dictionary_t filedict; 1106 char buf[MAXMODNAME]; 1107 const char *s, *p; 1108 int error; 1109 size_t len; 1110 1111 KASSERT(kernconfig_is_held()); 1112 1113 filedict = NULL; 1114 error = 0; 1115 1116 /* 1117 * Set up the pending list for this entry. If this is an 1118 * internal entry (for a dependency), then use the same list 1119 * as for the outer call; otherwise, it's an external entry 1120 * (possibly recursive, ie a module's xxx_modcmd(init, ...) 1121 * routine called us), so use the locally allocated list. In 1122 * either case, add it to our stack. 1123 */ 1124 if (isdep) { 1125 KASSERT(SLIST_FIRST(&pend_stack) != NULL); 1126 pending = SLIST_FIRST(&pend_stack)->pe_pending; 1127 } else 1128 pending = &new_pending; 1129 my_pend_entry.pe_pending = pending; 1130 SLIST_INSERT_HEAD(&pend_stack, &my_pend_entry, pe_entry); 1131 1132 /* 1133 * Search the list of disabled builtins first. 1134 */ 1135 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 1136 if (strcmp(mod->mod_info->mi_name, name) == 0) { 1137 break; 1138 } 1139 } 1140 if (mod) { 1141 if (ISSET(mod->mod_flags, MODFLG_MUST_FORCE) && 1142 !ISSET(flags, MODCTL_LOAD_FORCE)) { 1143 if (!autoload) { 1144 module_error("use -f to reinstate " 1145 "builtin module `%s'", name); 1146 } 1147 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1148 return EPERM; 1149 } else { 1150 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1151 error = module_do_builtin(mod, name, modp, props); 1152 return error; 1153 } 1154 } 1155 1156 /* 1157 * Load the module and link. Before going to the file system, 1158 * scan the list of modules loaded by the boot loader. 1159 */ 1160 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 1161 if (strcmp(mod->mod_info->mi_name, name) == 0) { 1162 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 1163 break; 1164 } 1165 } 1166 if (mod != NULL) { 1167 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 1168 } else { 1169 /* 1170 * Check to see if module is already present. 1171 */ 1172 mod = module_lookup(name); 1173 if (mod != NULL) { 1174 if (modp != NULL) { 1175 *modp = mod; 1176 } 1177 module_print("%s module `%s' already loaded", 1178 isdep ? "dependent" : "requested", name); 1179 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1180 return EEXIST; 1181 } 1182 1183 mod = module_newmodule(MODULE_SOURCE_FILESYS); 1184 if (mod == NULL) { 1185 module_error("out of memory for `%s'", name); 1186 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1187 return ENOMEM; 1188 } 1189 1190 error = module_load_vfs_vec(name, flags, autoload, mod, 1191 &filedict); 1192 if (error != 0) { 1193 #ifdef DEBUG 1194 /* 1195 * The exec class of modules contains a list of 1196 * modules that is the union of all the modules 1197 * available for each architecture, so we don't 1198 * print an error if they are missing. 1199 */ 1200 if ((modclass != MODULE_CLASS_EXEC || error != ENOENT) 1201 && root_device != NULL) 1202 module_error("vfs load failed for `%s', " 1203 "error %d", name, error); 1204 #endif 1205 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1206 module_free(mod); 1207 return error; 1208 } 1209 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 1210 1211 error = module_fetch_info(mod); 1212 if (error != 0) { 1213 module_error("cannot fetch info for `%s', error %d", 1214 name, error); 1215 goto fail; 1216 } 1217 } 1218 1219 /* 1220 * Check compatibility. 1221 */ 1222 mi = mod->mod_info; 1223 if (strnlen(mi->mi_name, MAXMODNAME) >= MAXMODNAME) { 1224 error = EINVAL; 1225 module_error("module name `%s' longer than %d", mi->mi_name, 1226 MAXMODNAME); 1227 goto fail; 1228 } 1229 if (mi->mi_class <= MODULE_CLASS_ANY || 1230 mi->mi_class >= MODULE_CLASS_MAX) { 1231 error = EINVAL; 1232 module_error("module `%s' has invalid class %d", 1233 mi->mi_name, mi->mi_class); 1234 goto fail; 1235 } 1236 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 1237 module_error("module `%s' built for `%d', system `%d'", 1238 mi->mi_name, mi->mi_version, __NetBSD_Version__); 1239 if (ISSET(flags, MODCTL_LOAD_FORCE)) { 1240 module_error("forced load, system may be unstable"); 1241 } else { 1242 error = EPROGMISMATCH; 1243 goto fail; 1244 } 1245 } 1246 1247 /* 1248 * If a specific kind of module was requested, ensure that we have 1249 * a match. 1250 */ 1251 if (!MODULE_CLASS_MATCH(mi, modclass)) { 1252 module_incompat(mi, modclass); 1253 error = ENOENT; 1254 goto fail; 1255 } 1256 1257 /* 1258 * If loading a dependency, `name' is a plain module name. 1259 * The name must match. 1260 */ 1261 if (isdep && strcmp(mi->mi_name, name) != 0) { 1262 module_error("dependency name mismatch (`%s' != `%s')", 1263 name, mi->mi_name); 1264 error = ENOENT; 1265 goto fail; 1266 } 1267 1268 /* 1269 * If we loaded a module from the filesystem, check the actual 1270 * module name (from the modinfo_t) to ensure another module 1271 * with the same name doesn't already exist. (There's no 1272 * guarantee the filename will match the module name, and the 1273 * dup-symbols check may not be sufficient.) 1274 */ 1275 if (mod->mod_source == MODULE_SOURCE_FILESYS) { 1276 mod2 = module_lookup(mod->mod_info->mi_name); 1277 if ( mod2 && mod2 != mod) { 1278 module_error("module with name `%s' already loaded", 1279 mod2->mod_info->mi_name); 1280 error = EEXIST; 1281 if (modp != NULL) 1282 *modp = mod2; 1283 goto fail; 1284 } 1285 } 1286 1287 /* 1288 * Block circular dependencies. 1289 */ 1290 TAILQ_FOREACH(mod2, pending, mod_chain) { 1291 if (mod == mod2) { 1292 continue; 1293 } 1294 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 1295 error = EDEADLK; 1296 module_error("circular dependency detected for `%s'", 1297 mi->mi_name); 1298 goto fail; 1299 } 1300 } 1301 1302 /* 1303 * Now try to load any requisite modules. 1304 */ 1305 if (mi->mi_required != NULL) { 1306 mod->mod_arequired = 0; 1307 for (s = mi->mi_required; *s != '\0'; s = p) { 1308 if (*s == ',') 1309 s++; 1310 p = s; 1311 while (*p != '\0' && *p != ',') 1312 p++; 1313 len = p - s + 1; 1314 if (len >= MAXMODNAME) { 1315 error = EINVAL; 1316 module_error("required module name `%s' " 1317 "longer than %d", mi->mi_required, 1318 MAXMODNAME); 1319 goto fail; 1320 } 1321 strlcpy(buf, s, len); 1322 if (buf[0] == '\0') 1323 break; 1324 alloc_required(mod); 1325 if (strcmp(buf, mi->mi_name) == 0) { 1326 error = EDEADLK; 1327 module_error("self-dependency detected for " 1328 "`%s'", mi->mi_name); 1329 goto fail; 1330 } 1331 error = module_do_load(buf, true, flags, NULL, 1332 &mod2, MODULE_CLASS_ANY, true); 1333 if (error != 0 && error != EEXIST) { 1334 module_error("recursive load failed for `%s' " 1335 "(`%s' required), error %d", mi->mi_name, 1336 buf, error); 1337 goto fail; 1338 } 1339 (*mod->mod_required)[mod->mod_nrequired++] = mod2; 1340 } 1341 } 1342 1343 /* 1344 * We loaded all needed modules successfully: perform global 1345 * relocations and initialize. 1346 */ 1347 { 1348 char xname[MAXMODNAME]; 1349 1350 /* 1351 * In case of error the entire module is gone, so we 1352 * need to save its name for possible error report. 1353 */ 1354 1355 strlcpy(xname, mi->mi_name, MAXMODNAME); 1356 error = kobj_affix(mod->mod_kobj, mi->mi_name); 1357 if (error != 0) { 1358 module_error("unable to affix module `%s', error %d", 1359 xname, error); 1360 goto fail2; 1361 } 1362 } 1363 1364 if (filedict) { 1365 if (!module_merge_dicts(filedict, props)) { 1366 module_error("module properties failed for %s", name); 1367 error = EINVAL; 1368 goto fail; 1369 } 1370 } 1371 1372 prev_active = module_active; 1373 module_active = mod; 1374 1375 /* 1376 * Note that we handle sysctl and evcnt setup _before_ we 1377 * initialize the module itself. This maintains a consistent 1378 * order between built-in and run-time-loaded modules. If 1379 * initialization then fails, we'll need to undo these, too. 1380 */ 1381 module_load_sysctl(mod); /* Set-up module's sysctl if any */ 1382 module_load_evcnt(mod); /* Attach any static evcnt needed */ 1383 1384 1385 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); 1386 module_active = prev_active; 1387 if (filedict) { 1388 prop_object_release(filedict); 1389 filedict = NULL; 1390 } 1391 if (error != 0) { 1392 module_error("modcmd(CMD_INIT) failed for `%s', error %d", 1393 mi->mi_name, error); 1394 goto fail3; 1395 } 1396 1397 /* 1398 * If a recursive load already added a module with the same 1399 * name, abort. 1400 */ 1401 mod2 = module_lookup(mi->mi_name); 1402 if (mod2 && mod2 != mod) { 1403 module_error("recursive load causes duplicate module `%s'", 1404 mi->mi_name); 1405 error = EEXIST; 1406 goto fail1; 1407 } 1408 1409 /* 1410 * Good, the module loaded successfully. Put it onto the 1411 * list and add references to its requisite modules. 1412 */ 1413 TAILQ_REMOVE(pending, mod, mod_chain); 1414 module_enqueue(mod); 1415 if (modp != NULL) { 1416 *modp = mod; 1417 } 1418 if (autoload && module_autotime > 0) { 1419 /* 1420 * Arrange to try unloading the module after 1421 * a short delay unless auto-unload is disabled. 1422 */ 1423 mod->mod_autotime = time_second + module_autotime; 1424 SET(mod->mod_flags, MODFLG_AUTO_LOADED); 1425 module_thread_kick(); 1426 } 1427 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1428 module_print("module `%s' loaded successfully", mi->mi_name); 1429 module_callback_load(mod); 1430 return 0; 1431 1432 fail1: 1433 (*mi->mi_modcmd)(MODULE_CMD_FINI, NULL); 1434 fail3: 1435 /* 1436 * If there were any registered SYSCTL_SETUP funcs, make sure 1437 * we release the sysctl entries 1438 */ 1439 if (mod->mod_sysctllog) { 1440 sysctl_teardown(&mod->mod_sysctllog); 1441 } 1442 /* Also detach any static evcnt's */ 1443 module_unload_evcnt(mod); 1444 fail: 1445 kobj_unload(mod->mod_kobj); 1446 fail2: 1447 if (filedict != NULL) { 1448 prop_object_release(filedict); 1449 filedict = NULL; 1450 } 1451 TAILQ_REMOVE(pending, mod, mod_chain); 1452 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1453 module_free(mod); 1454 return error; 1455 } 1456 1457 /* 1458 * module_do_unload: 1459 * 1460 * Helper routine: do the dirty work of unloading a module. 1461 */ 1462 static int 1463 module_do_unload(const char *name, bool load_requires_force) 1464 { 1465 module_t *mod, *prev_active; 1466 int error; 1467 u_int i; 1468 1469 KASSERT(kernconfig_is_held()); 1470 KASSERT(name != NULL); 1471 1472 module_print("unload requested for '%s' (%s)", name, 1473 load_requires_force ? "TRUE" : "FALSE"); 1474 mod = module_lookup(name); 1475 if (mod == NULL) { 1476 module_error("module `%s' not found", name); 1477 return ENOENT; 1478 } 1479 if (mod->mod_refcnt != 0) { 1480 module_print("module `%s' busy (%d refs)", name, 1481 mod->mod_refcnt); 1482 return EBUSY; 1483 } 1484 1485 /* 1486 * Builtin secmodels are there to stay. 1487 */ 1488 if (mod->mod_source == MODULE_SOURCE_KERNEL && 1489 mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) { 1490 module_print("cannot unload built-in secmodel module `%s'", 1491 name); 1492 return EPERM; 1493 } 1494 1495 prev_active = module_active; 1496 module_active = mod; 1497 module_callback_unload(mod); 1498 1499 /* let the module clean up after itself */ 1500 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 1501 1502 /* 1503 * If there were any registered SYSCTL_SETUP funcs, make sure 1504 * we release the sysctl entries. Same for static evcnt. 1505 */ 1506 if (error == 0) { 1507 if (mod->mod_sysctllog) { 1508 sysctl_teardown(&mod->mod_sysctllog); 1509 } 1510 module_unload_evcnt(mod); 1511 } 1512 module_active = prev_active; 1513 if (error != 0) { 1514 module_print("could not unload module `%s' error=%d", name, 1515 error); 1516 return error; 1517 } 1518 module_count--; 1519 TAILQ_REMOVE(&module_list, mod, mod_chain); 1520 for (i = 0; i < mod->mod_nrequired; i++) { 1521 (*mod->mod_required)[i]->mod_refcnt--; 1522 } 1523 module_print("unloaded module `%s'", name); 1524 if (mod->mod_kobj != NULL) { 1525 kobj_unload(mod->mod_kobj); 1526 } 1527 if (mod->mod_source == MODULE_SOURCE_KERNEL) { 1528 if (mod->mod_required != NULL) { 1529 /* 1530 * release "required" resources - will be re-parsed 1531 * if the module is re-enabled 1532 */ 1533 kmem_free(mod->mod_required, 1534 mod->mod_arequired * sizeof(module_t *)); 1535 mod->mod_nrequired = 0; 1536 mod->mod_arequired = 0; 1537 mod->mod_required = NULL; 1538 } 1539 if (load_requires_force) 1540 module_require_force(mod); 1541 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 1542 module_builtinlist++; 1543 } else { 1544 module_free(mod); 1545 } 1546 module_gen++; 1547 1548 return 0; 1549 } 1550 1551 /* 1552 * module_prime: 1553 * 1554 * Push a module loaded by the bootloader onto our internal 1555 * list. 1556 */ 1557 int 1558 module_prime(const char *name, void *base, size_t size) 1559 { 1560 __link_set_decl(modules, modinfo_t); 1561 modinfo_t *const *mip; 1562 module_t *mod; 1563 int error; 1564 1565 /* Check for module name same as a built-in module */ 1566 1567 __link_set_foreach(mip, modules) { 1568 if (*mip == &module_dummy) 1569 continue; 1570 if (strcmp((*mip)->mi_name, name) == 0) { 1571 module_error("module `%s' pushed by boot loader " 1572 "already exists", name); 1573 return EEXIST; 1574 } 1575 } 1576 1577 /* Also eliminate duplicate boolist entries */ 1578 1579 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 1580 if (strcmp(mod->mod_info->mi_name, name) == 0) { 1581 module_error("duplicate bootlist entry for module " 1582 "`%s'", name); 1583 return EEXIST; 1584 } 1585 } 1586 1587 mod = module_newmodule(MODULE_SOURCE_BOOT); 1588 if (mod == NULL) { 1589 return ENOMEM; 1590 } 1591 1592 error = kobj_load_mem(&mod->mod_kobj, name, base, size); 1593 if (error != 0) { 1594 module_free(mod); 1595 module_error("unable to load `%s' pushed by boot loader, " 1596 "error %d", name, error); 1597 return error; 1598 } 1599 error = module_fetch_info(mod); 1600 if (error != 0) { 1601 kobj_unload(mod->mod_kobj); 1602 module_free(mod); 1603 module_error("unable to fetch_info for `%s' pushed by boot " 1604 "loader, error %d", name, error); 1605 return error; 1606 } 1607 1608 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 1609 1610 return 0; 1611 } 1612 1613 /* 1614 * module_fetch_into: 1615 * 1616 * Fetch modinfo record from a loaded module. 1617 */ 1618 static int 1619 module_fetch_info(module_t *mod) 1620 { 1621 int error; 1622 void *addr; 1623 size_t size; 1624 1625 /* 1626 * Find module info record and check compatibility. 1627 */ 1628 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1629 &addr, &size); 1630 if (error != 0) { 1631 module_error("`link_set_modules' section not present, " 1632 "error %d", error); 1633 return error; 1634 } 1635 if (size != sizeof(modinfo_t **)) { 1636 module_error("`link_set_modules' section wrong size " 1637 "(got %zu, wanted %zu)", size, sizeof(modinfo_t **)); 1638 return ENOEXEC; 1639 } 1640 mod->mod_info = *(modinfo_t **)addr; 1641 1642 return 0; 1643 } 1644 1645 /* 1646 * module_find_section: 1647 * 1648 * Allows a module that is being initialized to look up a section 1649 * within its ELF object. 1650 */ 1651 int 1652 module_find_section(const char *name, void **addr, size_t *size) 1653 { 1654 1655 KASSERT(kernconfig_is_held()); 1656 KASSERT(module_active != NULL); 1657 1658 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1659 } 1660 1661 /* 1662 * module_thread: 1663 * 1664 * Automatically unload modules. We try once to unload autoloaded 1665 * modules after module_autotime seconds. If the system is under 1666 * severe memory pressure, we'll try unloading all modules, else if 1667 * module_autotime is zero, we don't try to unload, even if the 1668 * module was previously scheduled for unload. 1669 */ 1670 static void 1671 module_thread(void *cookie) 1672 { 1673 module_t *mod, *next; 1674 modinfo_t *mi; 1675 int error; 1676 1677 for (;;) { 1678 kernconfig_lock(); 1679 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1680 next = TAILQ_NEXT(mod, mod_chain); 1681 1682 /* skip built-in modules */ 1683 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1684 continue; 1685 /* skip modules that weren't auto-loaded */ 1686 if (!ISSET(mod->mod_flags, MODFLG_AUTO_LOADED)) 1687 continue; 1688 1689 if (uvm_availmem(false) < uvmexp.freemin) { 1690 module_thread_ticks = hz; 1691 } else if (module_autotime == 0 || 1692 mod->mod_autotime == 0) { 1693 continue; 1694 } else if (time_second < mod->mod_autotime) { 1695 module_thread_ticks = hz; 1696 continue; 1697 } else { 1698 mod->mod_autotime = 0; 1699 } 1700 1701 /* 1702 * Ask the module if it can be safely unloaded. 1703 * 1704 * - Modules which have been audited to be OK 1705 * with that will return 0. 1706 * 1707 * - Modules which have not been audited for 1708 * safe autounload will return ENOTTY. 1709 * 1710 * => With kern.module.autounload_unsafe=1, 1711 * we treat ENOTTY as acceptance. 1712 * 1713 * - Some modules would ping-ping in and out 1714 * because their use is transient but often. 1715 * Example: exec_script. Other modules may 1716 * still be in use. These modules can 1717 * prevent autounload in all cases by 1718 * returning EBUSY or some other error code. 1719 */ 1720 mi = mod->mod_info; 1721 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1722 if (error == 0 || 1723 (error == ENOTTY && module_autounload_unsafe)) { 1724 (void)module_do_unload(mi->mi_name, false); 1725 } else 1726 module_print("module `%s' declined to be " 1727 "auto-unloaded error=%d", mi->mi_name, 1728 error); 1729 } 1730 kernconfig_unlock(); 1731 1732 mutex_enter(&module_thread_lock); 1733 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1734 module_thread_ticks); 1735 module_thread_ticks = 0; 1736 mutex_exit(&module_thread_lock); 1737 } 1738 } 1739 1740 /* 1741 * module_thread: 1742 * 1743 * Kick the module thread into action, perhaps because the 1744 * system is low on memory. 1745 */ 1746 void 1747 module_thread_kick(void) 1748 { 1749 1750 mutex_enter(&module_thread_lock); 1751 module_thread_ticks = hz; 1752 cv_broadcast(&module_thread_cv); 1753 mutex_exit(&module_thread_lock); 1754 } 1755 1756 #ifdef DDB 1757 /* 1758 * module_whatis: 1759 * 1760 * Helper routine for DDB. 1761 */ 1762 void 1763 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1764 { 1765 module_t *mod; 1766 size_t msize; 1767 vaddr_t maddr; 1768 1769 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1770 if (mod->mod_kobj == NULL) { 1771 continue; 1772 } 1773 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1774 continue; 1775 if (addr < maddr || addr >= maddr + msize) { 1776 continue; 1777 } 1778 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1779 (void *)addr, (void *)maddr, 1780 (size_t)(addr - maddr), mod->mod_info->mi_name); 1781 } 1782 } 1783 1784 /* 1785 * module_print_list: 1786 * 1787 * Helper routine for DDB. 1788 */ 1789 void 1790 module_print_list(void (*pr)(const char *, ...)) 1791 { 1792 const char *src; 1793 module_t *mod; 1794 size_t msize; 1795 vaddr_t maddr; 1796 1797 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1798 1799 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1800 switch (mod->mod_source) { 1801 case MODULE_SOURCE_KERNEL: 1802 src = "builtin"; 1803 break; 1804 case MODULE_SOURCE_FILESYS: 1805 src = "filesys"; 1806 break; 1807 case MODULE_SOURCE_BOOT: 1808 src = "boot"; 1809 break; 1810 default: 1811 src = "unknown"; 1812 break; 1813 } 1814 if (mod->mod_kobj == NULL) { 1815 maddr = 0; 1816 msize = 0; 1817 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1818 continue; 1819 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1820 (long)maddr, (long)msize, src); 1821 } 1822 } 1823 #endif /* DDB */ 1824 1825 static bool 1826 module_merge_dicts(prop_dictionary_t existing_dict, 1827 const prop_dictionary_t new_dict) 1828 { 1829 prop_dictionary_keysym_t props_keysym; 1830 prop_object_iterator_t props_iter; 1831 prop_object_t props_obj; 1832 const char *props_key; 1833 bool error; 1834 1835 if (new_dict == NULL) { /* nothing to merge */ 1836 return true; 1837 } 1838 1839 error = false; 1840 props_iter = prop_dictionary_iterator(new_dict); 1841 if (props_iter == NULL) { 1842 return false; 1843 } 1844 1845 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1846 props_keysym = (prop_dictionary_keysym_t)props_obj; 1847 props_key = prop_dictionary_keysym_value(props_keysym); 1848 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1849 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1850 props_key, props_obj)) { 1851 error = true; 1852 goto out; 1853 } 1854 } 1855 error = false; 1856 1857 out: 1858 prop_object_iterator_release(props_iter); 1859 1860 return !error; 1861 } 1862 1863 /* 1864 * module_specific_key_create: 1865 * 1866 * Create a key for subsystem module-specific data. 1867 */ 1868 specificdata_key_t 1869 module_specific_key_create(specificdata_key_t *keyp, specificdata_dtor_t dtor) 1870 { 1871 1872 return specificdata_key_create(module_specificdata_domain, keyp, dtor); 1873 } 1874 1875 /* 1876 * module_specific_key_delete: 1877 * 1878 * Delete a key for subsystem module-specific data. 1879 */ 1880 void 1881 module_specific_key_delete(specificdata_key_t key) 1882 { 1883 1884 return specificdata_key_delete(module_specificdata_domain, key); 1885 } 1886 1887 /* 1888 * module_getspecific: 1889 * 1890 * Return module-specific data corresponding to the specified key. 1891 */ 1892 void * 1893 module_getspecific(module_t *mod, specificdata_key_t key) 1894 { 1895 1896 return specificdata_getspecific(module_specificdata_domain, 1897 &mod->mod_sdref, key); 1898 } 1899 1900 /* 1901 * module_setspecific: 1902 * 1903 * Set module-specific data corresponding to the specified key. 1904 */ 1905 void 1906 module_setspecific(module_t *mod, specificdata_key_t key, void *data) 1907 { 1908 1909 specificdata_setspecific(module_specificdata_domain, 1910 &mod->mod_sdref, key, data); 1911 } 1912 1913 /* 1914 * module_register_callbacks: 1915 * 1916 * Register a new set of callbacks to be called on module load/unload. 1917 * Call the load callback on each existing module. 1918 * Return an opaque handle for unregistering these later. 1919 */ 1920 void * 1921 module_register_callbacks(void (*load)(struct module *), 1922 void (*unload)(struct module *)) 1923 { 1924 struct module_callbacks *modcb; 1925 struct module *mod; 1926 1927 modcb = kmem_alloc(sizeof(*modcb), KM_SLEEP); 1928 modcb->modcb_load = load; 1929 modcb->modcb_unload = unload; 1930 1931 kernconfig_lock(); 1932 TAILQ_INSERT_TAIL(&modcblist, modcb, modcb_list); 1933 TAILQ_FOREACH_REVERSE(mod, &module_list, modlist, mod_chain) 1934 load(mod); 1935 kernconfig_unlock(); 1936 1937 return modcb; 1938 } 1939 1940 /* 1941 * module_unregister_callbacks: 1942 * 1943 * Unregister a previously-registered set of module load/unload callbacks. 1944 * Call the unload callback on each existing module. 1945 */ 1946 void 1947 module_unregister_callbacks(void *opaque) 1948 { 1949 struct module_callbacks *modcb; 1950 struct module *mod; 1951 1952 modcb = opaque; 1953 kernconfig_lock(); 1954 TAILQ_FOREACH(mod, &module_list, mod_chain) 1955 modcb->modcb_unload(mod); 1956 TAILQ_REMOVE(&modcblist, modcb, modcb_list); 1957 kernconfig_unlock(); 1958 kmem_free(modcb, sizeof(*modcb)); 1959 } 1960 1961 /* 1962 * module_callback_load: 1963 * 1964 * Helper routine: call all load callbacks on a module being loaded. 1965 */ 1966 static void 1967 module_callback_load(struct module *mod) 1968 { 1969 struct module_callbacks *modcb; 1970 1971 TAILQ_FOREACH(modcb, &modcblist, modcb_list) { 1972 modcb->modcb_load(mod); 1973 } 1974 } 1975 1976 /* 1977 * module_callback_unload: 1978 * 1979 * Helper routine: call all unload callbacks on a module being unloaded. 1980 */ 1981 static void 1982 module_callback_unload(struct module *mod) 1983 { 1984 struct module_callbacks *modcb; 1985 1986 TAILQ_FOREACH(modcb, &modcblist, modcb_list) { 1987 modcb->modcb_unload(mod); 1988 } 1989 } 1990