1 /* $NetBSD: kern_module.c,v 1.161 2023/01/31 13:21:37 riastradh 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 1.161 2023/01/31 13:21:37 riastradh 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
module_incompat(const modinfo_t * mi,int modclass)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 *
module_kernel(void)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
module_error(const char * fmt,...)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
module_print(const char * fmt,...)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 *
module_name(struct module * mod)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
module_source(struct module * mod)209 module_source(struct module *mod)
210 {
211
212 return mod->mod_source;
213 }
214
215 static int
module_listener_cb(kauth_cred_t cred,kauth_action_t action,void * cookie,void * arg0,void * arg1,void * arg2,void * arg3)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 *
module_newmodule(modsrc_t source)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
module_free(module_t * mod)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
module_require_force(struct module * mod)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
module_builtin_add(modinfo_t * const * mip,size_t nmodinfo,bool init)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
module_builtin_remove(modinfo_t * mi,bool fini)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
module_init(void)411 module_init(void)
412 {
413 __link_set_decl(modules, modinfo_t);
414 modinfo_t *const *mip;
415 int rv;
416
417 if (module_map == NULL) {
418 module_map = kernel_map;
419 }
420 cv_init(&module_thread_cv, "mod_unld");
421 mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE);
422 TAILQ_INIT(&modcblist);
423
424 #ifdef MODULAR /* XXX */
425 module_init_md();
426 #endif
427
428 #ifdef KERNEL_DIR
429 const char *booted_kernel = get_booted_kernel();
430 if (booted_kernel) {
431 char *ptr = strrchr(booted_kernel, '/');
432 snprintf(module_base, sizeof(module_base), "/%.*s/modules",
433 (int)(ptr - booted_kernel), booted_kernel);
434 } else {
435 strlcpy(module_base, "/netbsd/modules", sizeof(module_base));
436 printf("Cannot find kernel name, loading modules from \"%s\"\n",
437 module_base);
438 }
439 #else
440 if (!module_machine)
441 module_machine = machine;
442 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */
443 snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules",
444 module_machine, osrelease);
445 #else /* release */
446 snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules",
447 module_machine, __NetBSD_Version__ / 100000000,
448 __NetBSD_Version__ / 1000000 % 100);
449 #endif
450 #endif
451
452 module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM,
453 module_listener_cb, NULL);
454
455 __link_set_foreach(mip, modules) {
456 if ((rv = module_builtin_add(mip, 1, false)) != 0)
457 module_error("builtin %s failed: %d\n",
458 (*mip)->mi_name, rv);
459 }
460
461 sysctl_module_setup();
462 module_specificdata_domain = specificdata_domain_create();
463
464 module_netbsd = module_newmodule(MODULE_SOURCE_KERNEL);
465 module_netbsd->mod_refcnt = 1;
466 module_netbsd->mod_info = &module_netbsd_modinfo;
467 }
468
469 /*
470 * module_start_unload_thread:
471 *
472 * Start the auto unload kthread.
473 */
474 void
module_start_unload_thread(void)475 module_start_unload_thread(void)
476 {
477 int error;
478
479 error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread,
480 NULL, NULL, "modunload");
481 if (error != 0)
482 panic("%s: %d", __func__, error);
483 }
484
485 /*
486 * module_builtin_require_force
487 *
488 * Require MODCTL_MUST_FORCE to load any built-in modules that have
489 * not yet been initialized
490 */
491 void
module_builtin_require_force(void)492 module_builtin_require_force(void)
493 {
494 module_t *mod;
495
496 kernconfig_lock();
497 TAILQ_FOREACH(mod, &module_builtins, mod_chain) {
498 module_require_force(mod);
499 }
500 kernconfig_unlock();
501 }
502
503 static struct sysctllog *module_sysctllog;
504
505 static int
sysctl_module_autotime(SYSCTLFN_ARGS)506 sysctl_module_autotime(SYSCTLFN_ARGS)
507 {
508 struct sysctlnode node;
509 int t, error;
510
511 t = *(int *)rnode->sysctl_data;
512
513 node = *rnode;
514 node.sysctl_data = &t;
515 error = sysctl_lookup(SYSCTLFN_CALL(&node));
516 if (error || newp == NULL)
517 return (error);
518
519 if (t < 0)
520 return (EINVAL);
521
522 *(int *)rnode->sysctl_data = t;
523 return (0);
524 }
525
526 static void
sysctl_module_setup(void)527 sysctl_module_setup(void)
528 {
529 const struct sysctlnode *node = NULL;
530
531 sysctl_createv(&module_sysctllog, 0, NULL, &node,
532 CTLFLAG_PERMANENT,
533 CTLTYPE_NODE, "module",
534 SYSCTL_DESCR("Module options"),
535 NULL, 0, NULL, 0,
536 CTL_KERN, CTL_CREATE, CTL_EOL);
537
538 if (node == NULL)
539 return;
540
541 sysctl_createv(&module_sysctllog, 0, &node, NULL,
542 CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
543 CTLTYPE_BOOL, "autoload",
544 SYSCTL_DESCR("Enable automatic load of modules"),
545 NULL, 0, &module_autoload_on, 0,
546 CTL_CREATE, CTL_EOL);
547 sysctl_createv(&module_sysctllog, 0, &node, NULL,
548 CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
549 CTLTYPE_BOOL, "autounload_unsafe",
550 SYSCTL_DESCR("Enable automatic unload of unaudited modules"),
551 NULL, 0, &module_autounload_unsafe, 0,
552 CTL_CREATE, CTL_EOL);
553 sysctl_createv(&module_sysctllog, 0, &node, NULL,
554 CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
555 CTLTYPE_BOOL, "verbose",
556 SYSCTL_DESCR("Enable verbose output"),
557 NULL, 0, &module_verbose_on, 0,
558 CTL_CREATE, CTL_EOL);
559 sysctl_createv(&module_sysctllog, 0, &node, NULL,
560 CTLFLAG_PERMANENT | CTLFLAG_READONLY,
561 CTLTYPE_STRING, "path",
562 SYSCTL_DESCR("Default module load path"),
563 NULL, 0, module_base, 0,
564 CTL_CREATE, CTL_EOL);
565 sysctl_createv(&module_sysctllog, 0, &node, NULL,
566 CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
567 CTLTYPE_INT, "autotime",
568 SYSCTL_DESCR("Auto-unload delay"),
569 sysctl_module_autotime, 0, &module_autotime, 0,
570 CTL_CREATE, CTL_EOL);
571 }
572
573 /*
574 * module_init_class:
575 *
576 * Initialize all built-in and pre-loaded modules of the
577 * specified class.
578 */
579 void
module_init_class(modclass_t modclass)580 module_init_class(modclass_t modclass)
581 {
582 TAILQ_HEAD(, module) bi_fail = TAILQ_HEAD_INITIALIZER(bi_fail);
583 module_t *mod;
584 modinfo_t *mi;
585
586 kernconfig_lock();
587 /*
588 * Builtins first. These will not depend on pre-loaded modules
589 * (because the kernel would not link).
590 */
591 do {
592 TAILQ_FOREACH(mod, &module_builtins, mod_chain) {
593 mi = mod->mod_info;
594 if (!MODULE_CLASS_MATCH(mi, modclass))
595 continue;
596 /*
597 * If initializing a builtin module fails, don't try
598 * to load it again. But keep it around and queue it
599 * on the builtins list after we're done with module
600 * init. Don't set it to MODFLG_MUST_FORCE in case a
601 * future attempt to initialize can be successful.
602 * (If the module has previously been set to
603 * MODFLG_MUST_FORCE, don't try to override that!)
604 */
605 if (ISSET(mod->mod_flags, MODFLG_MUST_FORCE) ||
606 module_do_builtin(mod, mi->mi_name, NULL,
607 NULL) != 0) {
608 TAILQ_REMOVE(&module_builtins, mod, mod_chain);
609 TAILQ_INSERT_TAIL(&bi_fail, mod, mod_chain);
610 }
611 break;
612 }
613 } while (mod != NULL);
614
615 /*
616 * Now preloaded modules. These will be pulled off the
617 * list as we call module_do_load();
618 */
619 do {
620 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) {
621 mi = mod->mod_info;
622 if (!MODULE_CLASS_MATCH(mi, modclass))
623 continue;
624 module_do_load(mi->mi_name, false, 0, NULL, NULL,
625 modclass, false);
626 break;
627 }
628 } while (mod != NULL);
629
630 /* return failed builtin modules to builtin list */
631 while ((mod = TAILQ_FIRST(&bi_fail)) != NULL) {
632 TAILQ_REMOVE(&bi_fail, mod, mod_chain);
633 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain);
634 }
635
636 kernconfig_unlock();
637 }
638
639 /*
640 * module_compatible:
641 *
642 * Return true if the two supplied kernel versions are said to
643 * have the same binary interface for kernel code. The entire
644 * version is signficant for the development tree (-current),
645 * major and minor versions are significant for official
646 * releases of the system.
647 */
648 bool
module_compatible(int v1,int v2)649 module_compatible(int v1, int v2)
650 {
651
652 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */
653 return v1 == v2;
654 #else /* release */
655 return abs(v1 - v2) < 10000;
656 #endif
657 }
658
659 /*
660 * module_load:
661 *
662 * Load a single module from the file system.
663 */
664 int
module_load(const char * filename,int flags,prop_dictionary_t props,modclass_t modclass)665 module_load(const char *filename, int flags, prop_dictionary_t props,
666 modclass_t modclass)
667 {
668 module_t *mod;
669 int error;
670
671 /* Test if we already have the module loaded before
672 * authorizing so we have the opportunity to return EEXIST. */
673 kernconfig_lock();
674 mod = module_lookup(filename);
675 if (mod != NULL) {
676 module_print("%s module `%s' already loaded",
677 "requested", filename);
678 error = EEXIST;
679 goto out;
680 }
681
682 /* Authorize. */
683 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE,
684 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL);
685 if (error != 0)
686 goto out;
687
688 error = module_do_load(filename, false, flags, props, NULL, modclass,
689 false);
690
691 out:
692 kernconfig_unlock();
693 return error;
694 }
695
696 /*
697 * module_autoload:
698 *
699 * Load a single module from the file system, system initiated.
700 */
701 int
module_autoload(const char * filename,modclass_t modclass)702 module_autoload(const char *filename, modclass_t modclass)
703 {
704 int error;
705 struct proc *p = curlwp->l_proc;
706
707 kernconfig_lock();
708
709 /* Nothing if the user has disabled it. */
710 if (!module_autoload_on) {
711 kernconfig_unlock();
712 return EPERM;
713 }
714
715 /* Disallow path separators and magic symlinks. */
716 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL ||
717 strchr(filename, '.') != NULL) {
718 kernconfig_unlock();
719 return EPERM;
720 }
721
722 /* Authorize. */
723 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE,
724 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL);
725
726 if (error == 0)
727 error = module_do_load(filename, false, 0, NULL, NULL, modclass,
728 true);
729
730 module_print("Autoload for `%s' requested by pid %d (%s), status %d",
731 filename, p->p_pid, p->p_comm, error);
732 kernconfig_unlock();
733 return error;
734 }
735
736 /*
737 * module_unload:
738 *
739 * Find and unload a module by name.
740 */
741 int
module_unload(const char * name)742 module_unload(const char *name)
743 {
744 int error;
745
746 /* Authorize. */
747 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE,
748 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL);
749 if (error != 0) {
750 return error;
751 }
752
753 kernconfig_lock();
754 error = module_do_unload(name, true);
755 kernconfig_unlock();
756
757 return error;
758 }
759
760 /*
761 * module_lookup:
762 *
763 * Look up a module by name.
764 */
765 module_t *
module_lookup(const char * name)766 module_lookup(const char *name)
767 {
768 module_t *mod;
769
770 KASSERT(kernconfig_is_held());
771
772 TAILQ_FOREACH(mod, &module_list, mod_chain) {
773 if (strcmp(mod->mod_info->mi_name, name) == 0)
774 break;
775 }
776
777 return mod;
778 }
779
780 /*
781 * module_hold:
782 *
783 * Add a single reference to a module. It's the caller's
784 * responsibility to ensure that the reference is dropped
785 * later.
786 */
787 void
module_hold(module_t * mod)788 module_hold(module_t *mod)
789 {
790
791 kernconfig_lock();
792 mod->mod_refcnt++;
793 kernconfig_unlock();
794 }
795
796 /*
797 * module_rele:
798 *
799 * Release a reference acquired with module_hold().
800 */
801 void
module_rele(module_t * mod)802 module_rele(module_t *mod)
803 {
804
805 kernconfig_lock();
806 KASSERT(mod->mod_refcnt > 0);
807 mod->mod_refcnt--;
808 kernconfig_unlock();
809 }
810
811 /*
812 * module_enqueue:
813 *
814 * Put a module onto the global list and update counters.
815 */
816 void
module_enqueue(module_t * mod)817 module_enqueue(module_t *mod)
818 {
819 int i;
820
821 KASSERT(kernconfig_is_held());
822
823 /*
824 * Put new entry at the head of the queue so autounload can unload
825 * requisite modules with only one pass through the queue.
826 */
827 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain);
828 if (mod->mod_nrequired) {
829
830 /* Add references to the requisite modules. */
831 for (i = 0; i < mod->mod_nrequired; i++) {
832 KASSERT((*mod->mod_required)[i] != NULL);
833 (*mod->mod_required)[i]->mod_refcnt++;
834 }
835 }
836 module_count++;
837 module_gen++;
838 }
839
840 /*
841 * Our array of required module pointers starts with zero entries. If we
842 * need to add a new entry, and the list is already full, we reallocate a
843 * larger array, adding MAXMODDEPS entries.
844 */
845 static void
alloc_required(module_t * mod)846 alloc_required(module_t *mod)
847 {
848 module_t *(*new)[], *(*old)[];
849 int areq;
850 int i;
851
852 if (mod->mod_nrequired >= mod->mod_arequired) {
853 areq = mod->mod_arequired + MAXMODDEPS;
854 old = mod->mod_required;
855 new = kmem_zalloc(areq * sizeof(module_t *), KM_SLEEP);
856 for (i = 0; i < mod->mod_arequired; i++)
857 (*new)[i] = (*old)[i];
858 mod->mod_required = new;
859 if (old)
860 kmem_free(old, mod->mod_arequired * sizeof(module_t *));
861 mod->mod_arequired = areq;
862 }
863 }
864
865 /*
866 * module_do_builtin:
867 *
868 * Initialize a module from the list of modules that are
869 * already linked into the kernel.
870 */
871 static int
module_do_builtin(const module_t * pmod,const char * name,module_t ** modp,prop_dictionary_t props)872 module_do_builtin(const module_t *pmod, const char *name, module_t **modp,
873 prop_dictionary_t props)
874 {
875 const char *p, *s;
876 char buf[MAXMODNAME];
877 modinfo_t *mi = NULL;
878 module_t *mod, *mod2, *mod_loaded, *prev_active;
879 size_t len;
880 int error;
881
882 KASSERT(kernconfig_is_held());
883
884 /*
885 * Search the list to see if we have a module by this name.
886 */
887 TAILQ_FOREACH(mod, &module_builtins, mod_chain) {
888 if (strcmp(mod->mod_info->mi_name, name) == 0) {
889 mi = mod->mod_info;
890 break;
891 }
892 }
893
894 /*
895 * Check to see if already loaded. This might happen if we
896 * were already loaded as a dependency.
897 */
898 if ((mod_loaded = module_lookup(name)) != NULL) {
899 KASSERT(mod == NULL);
900 if (modp)
901 *modp = mod_loaded;
902 return 0;
903 }
904
905 /* Note! This is from TAILQ, not immediate above */
906 if (mi == NULL) {
907 /*
908 * XXX: We'd like to panic here, but currently in some
909 * cases (such as nfsserver + nfs), the dependee can be
910 * successfully linked without the dependencies.
911 */
912 module_error("built-in module %s can't find builtin "
913 "dependency `%s'", pmod->mod_info->mi_name, name);
914 return ENOENT;
915 }
916
917 /*
918 * Initialize pre-requisites.
919 */
920 KASSERT(mod->mod_required == NULL);
921 KASSERT(mod->mod_arequired == 0);
922 KASSERT(mod->mod_nrequired == 0);
923 if (mi->mi_required != NULL) {
924 for (s = mi->mi_required; *s != '\0'; s = p) {
925 if (*s == ',')
926 s++;
927 p = s;
928 while (*p != '\0' && *p != ',')
929 p++;
930 len = uimin(p - s + 1, sizeof(buf));
931 strlcpy(buf, s, len);
932 if (buf[0] == '\0')
933 break;
934 alloc_required(mod);
935 error = module_do_builtin(mod, buf, &mod2, NULL);
936 if (error != 0) {
937 module_error("built-in module %s prerequisite "
938 "%s failed, error %d", name, buf, error);
939 goto fail;
940 }
941 (*mod->mod_required)[mod->mod_nrequired++] = mod2;
942 }
943 }
944
945 /*
946 * Try to initialize the module.
947 */
948 prev_active = module_active;
949 module_active = mod;
950 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, props);
951 module_active = prev_active;
952 if (error != 0) {
953 module_error("built-in module %s failed its MODULE_CMD_INIT, "
954 "error %d", mi->mi_name, error);
955 goto fail;
956 }
957
958 /* load always succeeds after this point */
959
960 TAILQ_REMOVE(&module_builtins, mod, mod_chain);
961 module_builtinlist--;
962 if (modp != NULL) {
963 *modp = mod;
964 }
965 module_enqueue(mod);
966 return 0;
967
968 fail:
969 if (mod->mod_required)
970 kmem_free(mod->mod_required, mod->mod_arequired *
971 sizeof(module_t *));
972 mod->mod_arequired = 0;
973 mod->mod_nrequired = 0;
974 mod->mod_required = NULL;
975 return error;
976 }
977
978 /*
979 * module_load_sysctl
980 *
981 * Check to see if a non-builtin module has any SYSCTL_SETUP() routine(s)
982 * registered. If so, call it (them).
983 */
984
985 static void
module_load_sysctl(module_t * mod)986 module_load_sysctl(module_t *mod)
987 {
988 void (**ls_funcp)(struct sysctllog **);
989 void *ls_start;
990 size_t ls_size, count;
991 int error;
992
993 /*
994 * Built-in modules don't have a mod_kobj so we cannot search
995 * for their link_set_sysctl_funcs
996 */
997 if (mod->mod_source == MODULE_SOURCE_KERNEL)
998 return;
999
1000 error = kobj_find_section(mod->mod_kobj, "link_set_sysctl_funcs",
1001 &ls_start, &ls_size);
1002 if (error == 0) {
1003 count = ls_size / sizeof(ls_start);
1004 ls_funcp = ls_start;
1005 while (count--) {
1006 (**ls_funcp)(&mod->mod_sysctllog);
1007 ls_funcp++;
1008 }
1009 }
1010 }
1011
1012 /*
1013 * module_load_evcnt
1014 *
1015 * Check to see if a non-builtin module has any static evcnt's defined;
1016 * if so, attach them.
1017 */
1018
1019 static void
module_load_evcnt(module_t * mod)1020 module_load_evcnt(module_t *mod)
1021 {
1022 struct evcnt * const *ls_evp;
1023 void *ls_start;
1024 size_t ls_size, count;
1025 int error;
1026
1027 /*
1028 * Built-in modules' static evcnt stuff will be handled
1029 * automatically as part of general kernel initialization
1030 */
1031 if (mod->mod_source == MODULE_SOURCE_KERNEL)
1032 return;
1033
1034 error = kobj_find_section(mod->mod_kobj, "link_set_evcnts",
1035 &ls_start, &ls_size);
1036 if (error == 0) {
1037 count = ls_size / sizeof(*ls_evp);
1038 ls_evp = ls_start;
1039 while (count--) {
1040 evcnt_attach_static(*ls_evp++);
1041 }
1042 }
1043 }
1044
1045 /*
1046 * module_unload_evcnt
1047 *
1048 * Check to see if a non-builtin module has any static evcnt's defined;
1049 * if so, detach them.
1050 */
1051
1052 static void
module_unload_evcnt(module_t * mod)1053 module_unload_evcnt(module_t *mod)
1054 {
1055 struct evcnt * const *ls_evp;
1056 void *ls_start;
1057 size_t ls_size, count;
1058 int error;
1059
1060 /*
1061 * Built-in modules' static evcnt stuff will be handled
1062 * automatically as part of general kernel initialization
1063 */
1064 if (mod->mod_source == MODULE_SOURCE_KERNEL)
1065 return;
1066
1067 error = kobj_find_section(mod->mod_kobj, "link_set_evcnts",
1068 &ls_start, &ls_size);
1069 if (error == 0) {
1070 count = ls_size / sizeof(*ls_evp);
1071 ls_evp = (void *)((char *)ls_start + ls_size);
1072 while (count--) {
1073 evcnt_detach(*--ls_evp);
1074 }
1075 }
1076 }
1077
1078 /*
1079 * module_do_load:
1080 *
1081 * Helper routine: load a module from the file system, or one
1082 * pushed by the boot loader.
1083 */
1084 static int
module_do_load(const char * name,bool isdep,int flags,prop_dictionary_t props,module_t ** modp,modclass_t modclass,bool autoload)1085 module_do_load(const char *name, bool isdep, int flags,
1086 prop_dictionary_t props, module_t **modp, modclass_t modclass,
1087 bool autoload)
1088 {
1089 /* The pending list for this level of recursion */
1090 TAILQ_HEAD(pending_t, module);
1091 struct pending_t *pending;
1092 struct pending_t new_pending = TAILQ_HEAD_INITIALIZER(new_pending);
1093
1094 /* The stack of pending lists */
1095 static SLIST_HEAD(pend_head, pend_entry) pend_stack =
1096 SLIST_HEAD_INITIALIZER(pend_stack);
1097 struct pend_entry {
1098 SLIST_ENTRY(pend_entry) pe_entry;
1099 struct pending_t *pe_pending;
1100 } my_pend_entry;
1101
1102 modinfo_t *mi;
1103 module_t *mod, *mod2, *prev_active;
1104 prop_dictionary_t filedict;
1105 char buf[MAXMODNAME];
1106 const char *s, *p;
1107 int error;
1108 size_t len;
1109
1110 KASSERT(kernconfig_is_held());
1111
1112 filedict = NULL;
1113 error = 0;
1114
1115 /*
1116 * Set up the pending list for this entry. If this is an
1117 * internal entry (for a dependency), then use the same list
1118 * as for the outer call; otherwise, it's an external entry
1119 * (possibly recursive, ie a module's xxx_modcmd(init, ...)
1120 * routine called us), so use the locally allocated list. In
1121 * either case, add it to our stack.
1122 */
1123 if (isdep) {
1124 KASSERT(SLIST_FIRST(&pend_stack) != NULL);
1125 pending = SLIST_FIRST(&pend_stack)->pe_pending;
1126 } else
1127 pending = &new_pending;
1128 my_pend_entry.pe_pending = pending;
1129 SLIST_INSERT_HEAD(&pend_stack, &my_pend_entry, pe_entry);
1130
1131 /*
1132 * Search the list of disabled builtins first.
1133 */
1134 TAILQ_FOREACH(mod, &module_builtins, mod_chain) {
1135 if (strcmp(mod->mod_info->mi_name, name) == 0) {
1136 break;
1137 }
1138 }
1139 if (mod) {
1140 if (ISSET(mod->mod_flags, MODFLG_MUST_FORCE) &&
1141 !ISSET(flags, MODCTL_LOAD_FORCE)) {
1142 if (!autoload) {
1143 module_error("use -f to reinstate "
1144 "builtin module `%s'", name);
1145 }
1146 SLIST_REMOVE_HEAD(&pend_stack, pe_entry);
1147 return EPERM;
1148 } else {
1149 SLIST_REMOVE_HEAD(&pend_stack, pe_entry);
1150 error = module_do_builtin(mod, name, modp, props);
1151 return error;
1152 }
1153 }
1154
1155 /*
1156 * Load the module and link. Before going to the file system,
1157 * scan the list of modules loaded by the boot loader.
1158 */
1159 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) {
1160 if (strcmp(mod->mod_info->mi_name, name) == 0) {
1161 TAILQ_REMOVE(&module_bootlist, mod, mod_chain);
1162 break;
1163 }
1164 }
1165 if (mod != NULL) {
1166 TAILQ_INSERT_TAIL(pending, mod, mod_chain);
1167 } else {
1168 /*
1169 * Check to see if module is already present.
1170 */
1171 mod = module_lookup(name);
1172 if (mod != NULL) {
1173 if (modp != NULL) {
1174 *modp = mod;
1175 }
1176 module_print("%s module `%s' already loaded",
1177 isdep ? "dependent" : "requested", name);
1178 SLIST_REMOVE_HEAD(&pend_stack, pe_entry);
1179 return EEXIST;
1180 }
1181
1182 mod = module_newmodule(MODULE_SOURCE_FILESYS);
1183 if (mod == NULL) {
1184 module_error("out of memory for `%s'", name);
1185 SLIST_REMOVE_HEAD(&pend_stack, pe_entry);
1186 return ENOMEM;
1187 }
1188
1189 error = module_load_vfs_vec(name, flags, autoload, mod,
1190 &filedict);
1191 if (error != 0) {
1192 #ifdef DEBUG
1193 /*
1194 * The exec class of modules contains a list of
1195 * modules that is the union of all the modules
1196 * available for each architecture, so we don't
1197 * print an error if they are missing.
1198 */
1199 if ((modclass != MODULE_CLASS_EXEC || error != ENOENT)
1200 && root_device != NULL)
1201 module_error("vfs load failed for `%s', "
1202 "error %d", name, error);
1203 #endif
1204 SLIST_REMOVE_HEAD(&pend_stack, pe_entry);
1205 module_free(mod);
1206 return error;
1207 }
1208 TAILQ_INSERT_TAIL(pending, mod, mod_chain);
1209
1210 error = module_fetch_info(mod);
1211 if (error != 0) {
1212 module_error("cannot fetch info for `%s', error %d",
1213 name, error);
1214 goto fail;
1215 }
1216 }
1217
1218 /*
1219 * Check compatibility.
1220 */
1221 mi = mod->mod_info;
1222 if (strnlen(mi->mi_name, MAXMODNAME) >= MAXMODNAME) {
1223 error = EINVAL;
1224 module_error("module name `%s' longer than %d", mi->mi_name,
1225 MAXMODNAME);
1226 goto fail;
1227 }
1228 if (mi->mi_class <= MODULE_CLASS_ANY ||
1229 mi->mi_class >= MODULE_CLASS_MAX) {
1230 error = EINVAL;
1231 module_error("module `%s' has invalid class %d",
1232 mi->mi_name, mi->mi_class);
1233 goto fail;
1234 }
1235 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) {
1236 module_error("module `%s' built for `%d', system `%d'",
1237 mi->mi_name, mi->mi_version, __NetBSD_Version__);
1238 if (ISSET(flags, MODCTL_LOAD_FORCE)) {
1239 module_error("forced load, system may be unstable");
1240 } else {
1241 error = EPROGMISMATCH;
1242 goto fail;
1243 }
1244 }
1245
1246 /*
1247 * If a specific kind of module was requested, ensure that we have
1248 * a match.
1249 */
1250 if (!MODULE_CLASS_MATCH(mi, modclass)) {
1251 module_incompat(mi, modclass);
1252 error = ENOENT;
1253 goto fail;
1254 }
1255
1256 /*
1257 * If loading a dependency, `name' is a plain module name.
1258 * The name must match.
1259 */
1260 if (isdep && strcmp(mi->mi_name, name) != 0) {
1261 module_error("dependency name mismatch (`%s' != `%s')",
1262 name, mi->mi_name);
1263 error = ENOENT;
1264 goto fail;
1265 }
1266
1267 /*
1268 * If we loaded a module from the filesystem, check the actual
1269 * module name (from the modinfo_t) to ensure another module
1270 * with the same name doesn't already exist. (There's no
1271 * guarantee the filename will match the module name, and the
1272 * dup-symbols check may not be sufficient.)
1273 */
1274 if (mod->mod_source == MODULE_SOURCE_FILESYS) {
1275 mod2 = module_lookup(mod->mod_info->mi_name);
1276 if ( mod2 && mod2 != mod) {
1277 module_error("module with name `%s' already loaded",
1278 mod2->mod_info->mi_name);
1279 error = EEXIST;
1280 if (modp != NULL)
1281 *modp = mod2;
1282 goto fail;
1283 }
1284 }
1285
1286 /*
1287 * Block circular dependencies.
1288 */
1289 TAILQ_FOREACH(mod2, pending, mod_chain) {
1290 if (mod == mod2) {
1291 continue;
1292 }
1293 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) {
1294 error = EDEADLK;
1295 module_error("circular dependency detected for `%s'",
1296 mi->mi_name);
1297 goto fail;
1298 }
1299 }
1300
1301 /*
1302 * Now try to load any requisite modules.
1303 */
1304 if (mi->mi_required != NULL) {
1305 mod->mod_arequired = 0;
1306 for (s = mi->mi_required; *s != '\0'; s = p) {
1307 if (*s == ',')
1308 s++;
1309 p = s;
1310 while (*p != '\0' && *p != ',')
1311 p++;
1312 len = p - s + 1;
1313 if (len >= MAXMODNAME) {
1314 error = EINVAL;
1315 module_error("required module name `%s' "
1316 "longer than %d", mi->mi_required,
1317 MAXMODNAME);
1318 goto fail;
1319 }
1320 strlcpy(buf, s, len);
1321 if (buf[0] == '\0')
1322 break;
1323 alloc_required(mod);
1324 if (strcmp(buf, mi->mi_name) == 0) {
1325 error = EDEADLK;
1326 module_error("self-dependency detected for "
1327 "`%s'", mi->mi_name);
1328 goto fail;
1329 }
1330 error = module_do_load(buf, true, flags, NULL,
1331 &mod2, MODULE_CLASS_ANY, true);
1332 if (error != 0 && error != EEXIST) {
1333 module_error("recursive load failed for `%s' "
1334 "(`%s' required), error %d", mi->mi_name,
1335 buf, error);
1336 goto fail;
1337 }
1338 (*mod->mod_required)[mod->mod_nrequired++] = mod2;
1339 }
1340 }
1341
1342 /*
1343 * We loaded all needed modules successfully: perform global
1344 * relocations and initialize.
1345 */
1346 {
1347 char xname[MAXMODNAME];
1348
1349 /*
1350 * In case of error the entire module is gone, so we
1351 * need to save its name for possible error report.
1352 */
1353
1354 strlcpy(xname, mi->mi_name, MAXMODNAME);
1355 error = kobj_affix(mod->mod_kobj, mi->mi_name);
1356 if (error != 0) {
1357 module_error("unable to affix module `%s', error %d",
1358 xname, error);
1359 goto fail2;
1360 }
1361 }
1362
1363 if (filedict) {
1364 if (!module_merge_dicts(filedict, props)) {
1365 module_error("module properties failed for %s", name);
1366 error = EINVAL;
1367 goto fail;
1368 }
1369 }
1370
1371 prev_active = module_active;
1372 module_active = mod;
1373
1374 /*
1375 * Note that we handle sysctl and evcnt setup _before_ we
1376 * initialize the module itself. This maintains a consistent
1377 * order between built-in and run-time-loaded modules. If
1378 * initialization then fails, we'll need to undo these, too.
1379 */
1380 module_load_sysctl(mod); /* Set-up module's sysctl if any */
1381 module_load_evcnt(mod); /* Attach any static evcnt needed */
1382
1383
1384 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props);
1385 module_active = prev_active;
1386 if (filedict) {
1387 prop_object_release(filedict);
1388 filedict = NULL;
1389 }
1390 if (error != 0) {
1391 module_error("modcmd(CMD_INIT) failed for `%s', error %d",
1392 mi->mi_name, error);
1393 goto fail3;
1394 }
1395
1396 /*
1397 * If a recursive load already added a module with the same
1398 * name, abort.
1399 */
1400 mod2 = module_lookup(mi->mi_name);
1401 if (mod2 && mod2 != mod) {
1402 module_error("recursive load causes duplicate module `%s'",
1403 mi->mi_name);
1404 error = EEXIST;
1405 goto fail1;
1406 }
1407
1408 /*
1409 * Good, the module loaded successfully. Put it onto the
1410 * list and add references to its requisite modules.
1411 */
1412 TAILQ_REMOVE(pending, mod, mod_chain);
1413 module_enqueue(mod);
1414 if (modp != NULL) {
1415 *modp = mod;
1416 }
1417 if (autoload && module_autotime > 0) {
1418 /*
1419 * Arrange to try unloading the module after
1420 * a short delay unless auto-unload is disabled.
1421 */
1422 mod->mod_autotime = time_second + module_autotime;
1423 SET(mod->mod_flags, MODFLG_AUTO_LOADED);
1424 module_thread_kick();
1425 }
1426 SLIST_REMOVE_HEAD(&pend_stack, pe_entry);
1427 module_print("module `%s' loaded successfully", mi->mi_name);
1428 module_callback_load(mod);
1429 return 0;
1430
1431 fail1:
1432 (*mi->mi_modcmd)(MODULE_CMD_FINI, NULL);
1433 fail3:
1434 /*
1435 * If there were any registered SYSCTL_SETUP funcs, make sure
1436 * we release the sysctl entries
1437 */
1438 if (mod->mod_sysctllog) {
1439 sysctl_teardown(&mod->mod_sysctllog);
1440 }
1441 /* Also detach any static evcnt's */
1442 module_unload_evcnt(mod);
1443 fail:
1444 kobj_unload(mod->mod_kobj);
1445 fail2:
1446 if (filedict != NULL) {
1447 prop_object_release(filedict);
1448 filedict = NULL;
1449 }
1450 TAILQ_REMOVE(pending, mod, mod_chain);
1451 SLIST_REMOVE_HEAD(&pend_stack, pe_entry);
1452 module_free(mod);
1453 return error;
1454 }
1455
1456 /*
1457 * module_do_unload:
1458 *
1459 * Helper routine: do the dirty work of unloading a module.
1460 */
1461 static int
module_do_unload(const char * name,bool load_requires_force)1462 module_do_unload(const char *name, bool load_requires_force)
1463 {
1464 module_t *mod, *prev_active;
1465 int error;
1466 u_int i;
1467
1468 KASSERT(kernconfig_is_held());
1469 KASSERT(name != NULL);
1470
1471 module_print("unload requested for '%s' (%s)", name,
1472 load_requires_force ? "TRUE" : "FALSE");
1473 mod = module_lookup(name);
1474 if (mod == NULL) {
1475 module_error("module `%s' not found", name);
1476 return ENOENT;
1477 }
1478 if (mod->mod_refcnt != 0) {
1479 module_print("module `%s' busy (%d refs)", name,
1480 mod->mod_refcnt);
1481 return EBUSY;
1482 }
1483
1484 /*
1485 * Builtin secmodels are there to stay.
1486 */
1487 if (mod->mod_source == MODULE_SOURCE_KERNEL &&
1488 mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) {
1489 module_print("cannot unload built-in secmodel module `%s'",
1490 name);
1491 return EPERM;
1492 }
1493
1494 prev_active = module_active;
1495 module_active = mod;
1496 module_callback_unload(mod);
1497
1498 /* let the module clean up after itself */
1499 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL);
1500
1501 /*
1502 * If there were any registered SYSCTL_SETUP funcs, make sure
1503 * we release the sysctl entries. Same for static evcnt.
1504 */
1505 if (error == 0) {
1506 if (mod->mod_sysctllog) {
1507 sysctl_teardown(&mod->mod_sysctllog);
1508 }
1509 module_unload_evcnt(mod);
1510 }
1511 module_active = prev_active;
1512 if (error != 0) {
1513 module_print("could not unload module `%s' error=%d", name,
1514 error);
1515 return error;
1516 }
1517 module_count--;
1518 TAILQ_REMOVE(&module_list, mod, mod_chain);
1519 for (i = 0; i < mod->mod_nrequired; i++) {
1520 (*mod->mod_required)[i]->mod_refcnt--;
1521 }
1522 module_print("unloaded module `%s'", name);
1523 if (mod->mod_kobj != NULL) {
1524 kobj_unload(mod->mod_kobj);
1525 }
1526 if (mod->mod_source == MODULE_SOURCE_KERNEL) {
1527 if (mod->mod_required != NULL) {
1528 /*
1529 * release "required" resources - will be re-parsed
1530 * if the module is re-enabled
1531 */
1532 kmem_free(mod->mod_required,
1533 mod->mod_arequired * sizeof(module_t *));
1534 mod->mod_nrequired = 0;
1535 mod->mod_arequired = 0;
1536 mod->mod_required = NULL;
1537 }
1538 if (load_requires_force)
1539 module_require_force(mod);
1540 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain);
1541 module_builtinlist++;
1542 } else {
1543 module_free(mod);
1544 }
1545 module_gen++;
1546
1547 return 0;
1548 }
1549
1550 /*
1551 * module_prime:
1552 *
1553 * Push a module loaded by the bootloader onto our internal
1554 * list.
1555 */
1556 int
module_prime(const char * name,void * base,size_t size)1557 module_prime(const char *name, void *base, size_t size)
1558 {
1559 __link_set_decl(modules, modinfo_t);
1560 modinfo_t *const *mip;
1561 module_t *mod;
1562 int error;
1563
1564 /* Check for module name same as a built-in module */
1565
1566 __link_set_foreach(mip, modules) {
1567 if (*mip == &module_dummy)
1568 continue;
1569 if (strcmp((*mip)->mi_name, name) == 0) {
1570 module_error("module `%s' pushed by boot loader "
1571 "already exists", name);
1572 return EEXIST;
1573 }
1574 }
1575
1576 /* Also eliminate duplicate boolist entries */
1577
1578 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) {
1579 if (strcmp(mod->mod_info->mi_name, name) == 0) {
1580 module_error("duplicate bootlist entry for module "
1581 "`%s'", name);
1582 return EEXIST;
1583 }
1584 }
1585
1586 mod = module_newmodule(MODULE_SOURCE_BOOT);
1587 if (mod == NULL) {
1588 return ENOMEM;
1589 }
1590
1591 error = kobj_load_mem(&mod->mod_kobj, name, base, size);
1592 if (error != 0) {
1593 module_free(mod);
1594 module_error("unable to load `%s' pushed by boot loader, "
1595 "error %d", name, error);
1596 return error;
1597 }
1598 error = module_fetch_info(mod);
1599 if (error != 0) {
1600 kobj_unload(mod->mod_kobj);
1601 module_free(mod);
1602 module_error("unable to fetch_info for `%s' pushed by boot "
1603 "loader, error %d", name, error);
1604 return error;
1605 }
1606
1607 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain);
1608
1609 return 0;
1610 }
1611
1612 /*
1613 * module_fetch_into:
1614 *
1615 * Fetch modinfo record from a loaded module.
1616 */
1617 static int
module_fetch_info(module_t * mod)1618 module_fetch_info(module_t *mod)
1619 {
1620 int error;
1621 void *addr;
1622 size_t size;
1623
1624 /*
1625 * Find module info record and check compatibility.
1626 */
1627 error = kobj_find_section(mod->mod_kobj, "link_set_modules",
1628 &addr, &size);
1629 if (error != 0) {
1630 module_error("`link_set_modules' section not present, "
1631 "error %d", error);
1632 return error;
1633 }
1634 if (size != sizeof(modinfo_t **)) {
1635 if (size > sizeof(modinfo_t **) &&
1636 (size % sizeof(modinfo_t **)) == 0) {
1637 module_error("`link_set_modules' section wrong size "
1638 "(%zu different MODULE declarations?)",
1639 size / sizeof(modinfo_t **));
1640 } else {
1641 module_error("`link_set_modules' section wrong size "
1642 "(got %zu, wanted %zu)",
1643 size, sizeof(modinfo_t **));
1644 }
1645 return ENOEXEC;
1646 }
1647 mod->mod_info = *(modinfo_t **)addr;
1648
1649 return 0;
1650 }
1651
1652 /*
1653 * module_find_section:
1654 *
1655 * Allows a module that is being initialized to look up a section
1656 * within its ELF object.
1657 */
1658 int
module_find_section(const char * name,void ** addr,size_t * size)1659 module_find_section(const char *name, void **addr, size_t *size)
1660 {
1661
1662 KASSERT(kernconfig_is_held());
1663 KASSERT(module_active != NULL);
1664
1665 return kobj_find_section(module_active->mod_kobj, name, addr, size);
1666 }
1667
1668 /*
1669 * module_thread:
1670 *
1671 * Automatically unload modules. We try once to unload autoloaded
1672 * modules after module_autotime seconds. If the system is under
1673 * severe memory pressure, we'll try unloading all modules, else if
1674 * module_autotime is zero, we don't try to unload, even if the
1675 * module was previously scheduled for unload.
1676 */
1677 static void
module_thread(void * cookie)1678 module_thread(void *cookie)
1679 {
1680 module_t *mod, *next;
1681 modinfo_t *mi;
1682 int error;
1683
1684 for (;;) {
1685 kernconfig_lock();
1686 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) {
1687 next = TAILQ_NEXT(mod, mod_chain);
1688
1689 /* skip built-in modules */
1690 if (mod->mod_source == MODULE_SOURCE_KERNEL)
1691 continue;
1692 /* skip modules that weren't auto-loaded */
1693 if (!ISSET(mod->mod_flags, MODFLG_AUTO_LOADED))
1694 continue;
1695
1696 if (uvm_availmem(false) < uvmexp.freemin) {
1697 module_thread_ticks = hz;
1698 } else if (module_autotime == 0 ||
1699 mod->mod_autotime == 0) {
1700 continue;
1701 } else if (time_second < mod->mod_autotime) {
1702 module_thread_ticks = hz;
1703 continue;
1704 } else {
1705 mod->mod_autotime = 0;
1706 }
1707
1708 /*
1709 * Ask the module if it can be safely unloaded.
1710 *
1711 * - Modules which have been audited to be OK
1712 * with that will return 0.
1713 *
1714 * - Modules which have not been audited for
1715 * safe autounload will return ENOTTY.
1716 *
1717 * => With kern.module.autounload_unsafe=1,
1718 * we treat ENOTTY as acceptance.
1719 *
1720 * - Some modules would ping-ping in and out
1721 * because their use is transient but often.
1722 * Example: exec_script. Other modules may
1723 * still be in use. These modules can
1724 * prevent autounload in all cases by
1725 * returning EBUSY or some other error code.
1726 */
1727 mi = mod->mod_info;
1728 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL);
1729 if (error == 0 ||
1730 (error == ENOTTY && module_autounload_unsafe)) {
1731 (void)module_do_unload(mi->mi_name, false);
1732 } else
1733 module_print("module `%s' declined to be "
1734 "auto-unloaded error=%d", mi->mi_name,
1735 error);
1736 }
1737 kernconfig_unlock();
1738
1739 mutex_enter(&module_thread_lock);
1740 (void)cv_timedwait(&module_thread_cv, &module_thread_lock,
1741 module_thread_ticks);
1742 module_thread_ticks = 0;
1743 mutex_exit(&module_thread_lock);
1744 }
1745 }
1746
1747 /*
1748 * module_thread:
1749 *
1750 * Kick the module thread into action, perhaps because the
1751 * system is low on memory.
1752 */
1753 void
module_thread_kick(void)1754 module_thread_kick(void)
1755 {
1756
1757 mutex_enter(&module_thread_lock);
1758 module_thread_ticks = hz;
1759 cv_broadcast(&module_thread_cv);
1760 mutex_exit(&module_thread_lock);
1761 }
1762
1763 #ifdef DDB
1764 /*
1765 * module_whatis:
1766 *
1767 * Helper routine for DDB.
1768 */
1769 void
module_whatis(uintptr_t addr,void (* pr)(const char *,...))1770 module_whatis(uintptr_t addr, void (*pr)(const char *, ...))
1771 {
1772 module_t *mod;
1773 size_t msize;
1774 vaddr_t maddr;
1775
1776 TAILQ_FOREACH(mod, &module_list, mod_chain) {
1777 if (mod->mod_kobj == NULL) {
1778 continue;
1779 }
1780 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0)
1781 continue;
1782 if (addr < maddr || addr >= maddr + msize) {
1783 continue;
1784 }
1785 (*pr)("%p is %p+%zu, in kernel module `%s'\n",
1786 (void *)addr, (void *)maddr,
1787 (size_t)(addr - maddr), mod->mod_info->mi_name);
1788 }
1789 }
1790
1791 /*
1792 * module_print_list:
1793 *
1794 * Helper routine for DDB.
1795 */
1796 void
module_print_list(void (* pr)(const char *,...))1797 module_print_list(void (*pr)(const char *, ...))
1798 {
1799 const char *src;
1800 module_t *mod;
1801 size_t msize;
1802 vaddr_t maddr;
1803
1804 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE");
1805
1806 TAILQ_FOREACH(mod, &module_list, mod_chain) {
1807 switch (mod->mod_source) {
1808 case MODULE_SOURCE_KERNEL:
1809 src = "builtin";
1810 break;
1811 case MODULE_SOURCE_FILESYS:
1812 src = "filesys";
1813 break;
1814 case MODULE_SOURCE_BOOT:
1815 src = "boot";
1816 break;
1817 default:
1818 src = "unknown";
1819 break;
1820 }
1821 if (mod->mod_kobj == NULL) {
1822 maddr = 0;
1823 msize = 0;
1824 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0)
1825 continue;
1826 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name,
1827 (long)maddr, (long)msize, src);
1828 }
1829 }
1830 #endif /* DDB */
1831
1832 static bool
module_merge_dicts(prop_dictionary_t existing_dict,const prop_dictionary_t new_dict)1833 module_merge_dicts(prop_dictionary_t existing_dict,
1834 const prop_dictionary_t new_dict)
1835 {
1836 prop_dictionary_keysym_t props_keysym;
1837 prop_object_iterator_t props_iter;
1838 prop_object_t props_obj;
1839 const char *props_key;
1840 bool error;
1841
1842 if (new_dict == NULL) { /* nothing to merge */
1843 return true;
1844 }
1845
1846 error = false;
1847 props_iter = prop_dictionary_iterator(new_dict);
1848 if (props_iter == NULL) {
1849 return false;
1850 }
1851
1852 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) {
1853 props_keysym = (prop_dictionary_keysym_t)props_obj;
1854 props_key = prop_dictionary_keysym_value(props_keysym);
1855 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym);
1856 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict,
1857 props_key, props_obj)) {
1858 error = true;
1859 goto out;
1860 }
1861 }
1862 error = false;
1863
1864 out:
1865 prop_object_iterator_release(props_iter);
1866
1867 return !error;
1868 }
1869
1870 /*
1871 * module_specific_key_create:
1872 *
1873 * Create a key for subsystem module-specific data.
1874 */
1875 specificdata_key_t
module_specific_key_create(specificdata_key_t * keyp,specificdata_dtor_t dtor)1876 module_specific_key_create(specificdata_key_t *keyp, specificdata_dtor_t dtor)
1877 {
1878
1879 return specificdata_key_create(module_specificdata_domain, keyp, dtor);
1880 }
1881
1882 /*
1883 * module_specific_key_delete:
1884 *
1885 * Delete a key for subsystem module-specific data.
1886 */
1887 void
module_specific_key_delete(specificdata_key_t key)1888 module_specific_key_delete(specificdata_key_t key)
1889 {
1890
1891 return specificdata_key_delete(module_specificdata_domain, key);
1892 }
1893
1894 /*
1895 * module_getspecific:
1896 *
1897 * Return module-specific data corresponding to the specified key.
1898 */
1899 void *
module_getspecific(module_t * mod,specificdata_key_t key)1900 module_getspecific(module_t *mod, specificdata_key_t key)
1901 {
1902
1903 return specificdata_getspecific(module_specificdata_domain,
1904 &mod->mod_sdref, key);
1905 }
1906
1907 /*
1908 * module_setspecific:
1909 *
1910 * Set module-specific data corresponding to the specified key.
1911 */
1912 void
module_setspecific(module_t * mod,specificdata_key_t key,void * data)1913 module_setspecific(module_t *mod, specificdata_key_t key, void *data)
1914 {
1915
1916 specificdata_setspecific(module_specificdata_domain,
1917 &mod->mod_sdref, key, data);
1918 }
1919
1920 /*
1921 * module_register_callbacks:
1922 *
1923 * Register a new set of callbacks to be called on module load/unload.
1924 * Call the load callback on each existing module.
1925 * Return an opaque handle for unregistering these later.
1926 */
1927 void *
module_register_callbacks(void (* load)(struct module *),void (* unload)(struct module *))1928 module_register_callbacks(void (*load)(struct module *),
1929 void (*unload)(struct module *))
1930 {
1931 struct module_callbacks *modcb;
1932 struct module *mod;
1933
1934 modcb = kmem_alloc(sizeof(*modcb), KM_SLEEP);
1935 modcb->modcb_load = load;
1936 modcb->modcb_unload = unload;
1937
1938 kernconfig_lock();
1939 TAILQ_INSERT_TAIL(&modcblist, modcb, modcb_list);
1940 TAILQ_FOREACH_REVERSE(mod, &module_list, modlist, mod_chain)
1941 load(mod);
1942 kernconfig_unlock();
1943
1944 return modcb;
1945 }
1946
1947 /*
1948 * module_unregister_callbacks:
1949 *
1950 * Unregister a previously-registered set of module load/unload callbacks.
1951 * Call the unload callback on each existing module.
1952 */
1953 void
module_unregister_callbacks(void * opaque)1954 module_unregister_callbacks(void *opaque)
1955 {
1956 struct module_callbacks *modcb;
1957 struct module *mod;
1958
1959 modcb = opaque;
1960 kernconfig_lock();
1961 TAILQ_FOREACH(mod, &module_list, mod_chain)
1962 modcb->modcb_unload(mod);
1963 TAILQ_REMOVE(&modcblist, modcb, modcb_list);
1964 kernconfig_unlock();
1965 kmem_free(modcb, sizeof(*modcb));
1966 }
1967
1968 /*
1969 * module_callback_load:
1970 *
1971 * Helper routine: call all load callbacks on a module being loaded.
1972 */
1973 static void
module_callback_load(struct module * mod)1974 module_callback_load(struct module *mod)
1975 {
1976 struct module_callbacks *modcb;
1977
1978 TAILQ_FOREACH(modcb, &modcblist, modcb_list) {
1979 modcb->modcb_load(mod);
1980 }
1981 }
1982
1983 /*
1984 * module_callback_unload:
1985 *
1986 * Helper routine: call all unload callbacks on a module being unloaded.
1987 */
1988 static void
module_callback_unload(struct module * mod)1989 module_callback_unload(struct module *mod)
1990 {
1991 struct module_callbacks *modcb;
1992
1993 TAILQ_FOREACH(modcb, &modcblist, modcb_list) {
1994 modcb->modcb_unload(mod);
1995 }
1996 }
1997