1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 1997-2000 Doug Rabson
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31
32 #include "opt_ddb.h"
33 #include "opt_kld.h"
34 #include "opt_hwpmc_hooks.h"
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/boottrace.h>
39 #include <sys/eventhandler.h>
40 #include <sys/fcntl.h>
41 #include <sys/jail.h>
42 #include <sys/kernel.h>
43 #include <sys/libkern.h>
44 #include <sys/linker.h>
45 #include <sys/lock.h>
46 #include <sys/malloc.h>
47 #include <sys/module.h>
48 #include <sys/mount.h>
49 #include <sys/mutex.h>
50 #include <sys/namei.h>
51 #include <sys/priv.h>
52 #include <sys/proc.h>
53 #include <sys/sx.h>
54 #include <sys/syscallsubr.h>
55 #include <sys/sysctl.h>
56 #include <sys/sysproto.h>
57 #include <sys/vnode.h>
58
59 #ifdef DDB
60 #include <ddb/ddb.h>
61 #endif
62
63 #include <net/vnet.h>
64
65 #include <security/mac/mac_framework.h>
66
67 #include "linker_if.h"
68
69 #ifdef HWPMC_HOOKS
70 #include <sys/pmckern.h>
71 #endif
72
73 #ifdef KLD_DEBUG
74 int kld_debug = 0;
75 SYSCTL_INT(_debug, OID_AUTO, kld_debug, CTLFLAG_RWTUN,
76 &kld_debug, 0, "Set various levels of KLD debug");
77 #endif
78
79 /* These variables are used by kernel debuggers to enumerate loaded files. */
80 const int kld_off_address = offsetof(struct linker_file, address);
81 const int kld_off_filename = offsetof(struct linker_file, filename);
82 const int kld_off_pathname = offsetof(struct linker_file, pathname);
83 const int kld_off_next = offsetof(struct linker_file, link.tqe_next);
84
85 /*
86 * static char *linker_search_path(const char *name, struct mod_depend
87 * *verinfo);
88 */
89 static const char *linker_basename(const char *path);
90
91 /*
92 * Find a currently loaded file given its filename.
93 */
94 static linker_file_t linker_find_file_by_name(const char* _filename);
95
96 /*
97 * Find a currently loaded file given its file id.
98 */
99 static linker_file_t linker_find_file_by_id(int _fileid);
100
101 /* Metadata from the static kernel */
102 SET_DECLARE(modmetadata_set, struct mod_metadata);
103
104 MALLOC_DEFINE(M_LINKER, "linker", "kernel linker");
105
106 linker_file_t linker_kernel_file;
107
108 static struct sx kld_sx; /* kernel linker lock */
109 static u_int kld_busy;
110 static struct thread *kld_busy_owner;
111
112 /*
113 * Load counter used by clients to determine if a linker file has been
114 * re-loaded. This counter is incremented for each file load.
115 */
116 static int loadcnt;
117
118 static linker_class_list_t classes;
119 static linker_file_list_t linker_files;
120 static int next_file_id = 1;
121 static int linker_no_more_classes = 0;
122
123 #define LINKER_GET_NEXT_FILE_ID(a) do { \
124 linker_file_t lftmp; \
125 \
126 if (!cold) \
127 sx_assert(&kld_sx, SA_XLOCKED); \
128 retry: \
129 TAILQ_FOREACH(lftmp, &linker_files, link) { \
130 if (next_file_id == lftmp->id) { \
131 next_file_id++; \
132 goto retry; \
133 } \
134 } \
135 (a) = next_file_id; \
136 } while (0)
137
138 /* XXX wrong name; we're looking at version provision tags here, not modules */
139 typedef TAILQ_HEAD(, modlist) modlisthead_t;
140 struct modlist {
141 TAILQ_ENTRY(modlist) link; /* chain together all modules */
142 linker_file_t container;
143 const char *name;
144 int version;
145 };
146 typedef struct modlist *modlist_t;
147 static modlisthead_t found_modules;
148
149 static int linker_file_add_dependency(linker_file_t file,
150 linker_file_t dep);
151 static caddr_t linker_file_lookup_symbol_internal(linker_file_t file,
152 const char* name, int deps);
153 static int linker_load_module(const char *kldname,
154 const char *modname, struct linker_file *parent,
155 const struct mod_depend *verinfo, struct linker_file **lfpp);
156 static modlist_t modlist_lookup2(const char *name, const struct mod_depend *verinfo);
157
158 static void
159 linker_init(void *arg)
160 {
161
162 sx_init(&kld_sx, "kernel linker");
163 TAILQ_INIT(&classes);
164 TAILQ_INIT(&linker_files);
165 }
166
167 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, NULL);
168
169 static void
170 linker_stop_class_add(void *arg)
171 {
172
173 linker_no_more_classes = 1;
174 }
175
176 SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL);
177
178 int
179 linker_add_class(linker_class_t lc)
180 {
181
182 /*
183 * We disallow any class registration past SI_ORDER_ANY
184 * of SI_SUB_KLD. We bump the reference count to keep the
185 * ops from being freed.
186 */
187 if (linker_no_more_classes == 1)
188 return (EPERM);
189 kobj_class_compile((kobj_class_t) lc);
190 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */
191 TAILQ_INSERT_TAIL(&classes, lc, link);
192 return (0);
193 }
194
195 static void
196 linker_file_sysinit(linker_file_t lf)
197 {
198 struct sysinit **start, **stop, **sipp, **xipp, *save;
199 int last;
200
201 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n",
202 lf->filename));
203
204 sx_assert(&kld_sx, SA_XLOCKED);
205
206 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0)
207 return;
208 /*
209 * Perform a bubble sort of the system initialization objects by
210 * their subsystem (primary key) and order (secondary key).
211 *
212 * Since some things care about execution order, this is the operation
213 * which ensures continued function.
214 */
215 for (sipp = start; sipp < stop; sipp++) {
216 for (xipp = sipp + 1; xipp < stop; xipp++) {
217 if ((*sipp)->subsystem < (*xipp)->subsystem ||
218 ((*sipp)->subsystem == (*xipp)->subsystem &&
219 (*sipp)->order <= (*xipp)->order))
220 continue; /* skip */
221 save = *sipp;
222 *sipp = *xipp;
223 *xipp = save;
224 }
225 }
226
227 /*
228 * Traverse the (now) ordered list of system initialization tasks.
229 * Perform each task, and continue on to the next task.
230 */
231 last = SI_SUB_DUMMY;
232 sx_xunlock(&kld_sx);
233 mtx_lock(&Giant);
234 for (sipp = start; sipp < stop; sipp++) {
235 if ((*sipp)->subsystem == SI_SUB_DUMMY)
236 continue; /* skip dummy task(s) */
237
238 if ((*sipp)->subsystem > last)
239 BOOTTRACE("%s: sysinit 0x%7x", lf->filename,
240 (*sipp)->subsystem);
241
242 /* Call function */
243 (*((*sipp)->func)) ((*sipp)->udata);
244 last = (*sipp)->subsystem;
245 }
246 mtx_unlock(&Giant);
247 sx_xlock(&kld_sx);
248 }
249
250 static void
251 linker_file_sysuninit(linker_file_t lf)
252 {
253 struct sysinit **start, **stop, **sipp, **xipp, *save;
254 int last;
255
256 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n",
257 lf->filename));
258
259 sx_assert(&kld_sx, SA_XLOCKED);
260
261 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop,
262 NULL) != 0)
263 return;
264
265 /*
266 * Perform a reverse bubble sort of the system initialization objects
267 * by their subsystem (primary key) and order (secondary key).
268 *
269 * Since some things care about execution order, this is the operation
270 * which ensures continued function.
271 */
272 for (sipp = start; sipp < stop; sipp++) {
273 for (xipp = sipp + 1; xipp < stop; xipp++) {
274 if ((*sipp)->subsystem > (*xipp)->subsystem ||
275 ((*sipp)->subsystem == (*xipp)->subsystem &&
276 (*sipp)->order >= (*xipp)->order))
277 continue; /* skip */
278 save = *sipp;
279 *sipp = *xipp;
280 *xipp = save;
281 }
282 }
283
284 /*
285 * Traverse the (now) ordered list of system initialization tasks.
286 * Perform each task, and continue on to the next task.
287 */
288 sx_xunlock(&kld_sx);
289 mtx_lock(&Giant);
290 last = SI_SUB_DUMMY;
291 for (sipp = start; sipp < stop; sipp++) {
292 if ((*sipp)->subsystem == SI_SUB_DUMMY)
293 continue; /* skip dummy task(s) */
294
295 if ((*sipp)->subsystem > last)
296 BOOTTRACE("%s: sysuninit 0x%7x", lf->filename,
297 (*sipp)->subsystem);
298
299 /* Call function */
300 (*((*sipp)->func)) ((*sipp)->udata);
301 last = (*sipp)->subsystem;
302 }
303 mtx_unlock(&Giant);
304 sx_xlock(&kld_sx);
305 }
306
307 static void
308 linker_file_register_sysctls(linker_file_t lf, bool enable)
309 {
310 struct sysctl_oid **start, **stop, **oidp;
311
312 KLD_DPF(FILE,
313 ("linker_file_register_sysctls: registering SYSCTLs for %s\n",
314 lf->filename));
315
316 sx_assert(&kld_sx, SA_XLOCKED);
317
318 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
319 return;
320
321 sx_xunlock(&kld_sx);
322 sysctl_wlock();
323 for (oidp = start; oidp < stop; oidp++) {
324 if (enable)
325 sysctl_register_oid(*oidp);
326 else
327 sysctl_register_disabled_oid(*oidp);
328 }
329 sysctl_wunlock();
330 sx_xlock(&kld_sx);
331 }
332
333 static void
334 linker_file_enable_sysctls(linker_file_t lf)
335 {
336 struct sysctl_oid **start, **stop, **oidp;
337
338 KLD_DPF(FILE,
339 ("linker_file_enable_sysctls: enable SYSCTLs for %s\n",
340 lf->filename));
341
342 sx_assert(&kld_sx, SA_XLOCKED);
343
344 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
345 return;
346
347 sx_xunlock(&kld_sx);
348 sysctl_wlock();
349 for (oidp = start; oidp < stop; oidp++)
350 sysctl_enable_oid(*oidp);
351 sysctl_wunlock();
352 sx_xlock(&kld_sx);
353 }
354
355 static void
356 linker_file_unregister_sysctls(linker_file_t lf)
357 {
358 struct sysctl_oid **start, **stop, **oidp;
359
360 KLD_DPF(FILE, ("linker_file_unregister_sysctls: unregistering SYSCTLs"
361 " for %s\n", lf->filename));
362
363 sx_assert(&kld_sx, SA_XLOCKED);
364
365 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
366 return;
367
368 sx_xunlock(&kld_sx);
369 sysctl_wlock();
370 for (oidp = start; oidp < stop; oidp++)
371 sysctl_unregister_oid(*oidp);
372 sysctl_wunlock();
373 sx_xlock(&kld_sx);
374 }
375
376 static int
377 linker_file_register_modules(linker_file_t lf)
378 {
379 struct mod_metadata **start, **stop, **mdp;
380 const moduledata_t *moddata;
381 int first_error, error;
382
383 KLD_DPF(FILE, ("linker_file_register_modules: registering modules"
384 " in %s\n", lf->filename));
385
386 sx_assert(&kld_sx, SA_XLOCKED);
387
388 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL) != 0) {
389 /*
390 * This fallback should be unnecessary, but if we get booted
391 * from boot2 instead of loader and we are missing our
392 * metadata then we have to try the best we can.
393 */
394 if (lf == linker_kernel_file) {
395 start = SET_BEGIN(modmetadata_set);
396 stop = SET_LIMIT(modmetadata_set);
397 } else
398 return (0);
399 }
400 first_error = 0;
401 for (mdp = start; mdp < stop; mdp++) {
402 if ((*mdp)->md_type != MDT_MODULE)
403 continue;
404 moddata = (*mdp)->md_data;
405 KLD_DPF(FILE, ("Registering module %s in %s\n",
406 moddata->name, lf->filename));
407 error = module_register(moddata, lf);
408 if (error) {
409 printf("Module %s failed to register: %d\n",
410 moddata->name, error);
411 if (first_error == 0)
412 first_error = error;
413 }
414 }
415 return (first_error);
416 }
417
418 static void
419 linker_init_kernel_modules(void)
420 {
421
422 sx_xlock(&kld_sx);
423 linker_file_register_modules(linker_kernel_file);
424 sx_xunlock(&kld_sx);
425 }
426
427 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules,
428 NULL);
429
430 static int
431 linker_load_file(const char *filename, linker_file_t *result)
432 {
433 linker_class_t lc;
434 linker_file_t lf;
435 int foundfile, error, modules;
436
437 /* Refuse to load modules if securelevel raised */
438 if (prison0.pr_securelevel > 0)
439 return (EPERM);
440
441 sx_assert(&kld_sx, SA_XLOCKED);
442 lf = linker_find_file_by_name(filename);
443 if (lf) {
444 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded,"
445 " incrementing refs\n", filename));
446 *result = lf;
447 lf->refs++;
448 return (0);
449 }
450 foundfile = 0;
451 error = 0;
452
453 /*
454 * We do not need to protect (lock) classes here because there is
455 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY)
456 * and there is no class deregistration mechanism at this time.
457 */
458 TAILQ_FOREACH(lc, &classes, link) {
459 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n",
460 filename));
461 error = LINKER_LOAD_FILE(lc, filename, &lf);
462 /*
463 * If we got something other than ENOENT, then it exists but
464 * we cannot load it for some other reason.
465 */
466 if (error != ENOENT)
467 foundfile = 1;
468 if (lf) {
469 error = linker_file_register_modules(lf);
470 if (error == EEXIST) {
471 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
472 return (error);
473 }
474 modules = !TAILQ_EMPTY(&lf->modules);
475 linker_file_register_sysctls(lf, false);
476 linker_file_sysinit(lf);
477 lf->flags |= LINKER_FILE_LINKED;
478
479 /*
480 * If all of the modules in this file failed
481 * to load, unload the file and return an
482 * error of ENOEXEC.
483 */
484 if (modules && TAILQ_EMPTY(&lf->modules)) {
485 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
486 return (ENOEXEC);
487 }
488 linker_file_enable_sysctls(lf);
489 EVENTHANDLER_INVOKE(kld_load, lf);
490 *result = lf;
491 return (0);
492 }
493 }
494 /*
495 * Less than ideal, but tells the user whether it failed to load or
496 * the module was not found.
497 */
498 if (foundfile) {
499 /*
500 * If the file type has not been recognized by the last try
501 * printout a message before to fail.
502 */
503 if (error == ENOSYS)
504 printf("%s: %s - unsupported file type\n",
505 __func__, filename);
506
507 /*
508 * Format not recognized or otherwise unloadable.
509 * When loading a module that is statically built into
510 * the kernel EEXIST percolates back up as the return
511 * value. Preserve this so that apps like sysinstall
512 * can recognize this special case and not post bogus
513 * dialog boxes.
514 */
515 if (error != EEXIST)
516 error = ENOEXEC;
517 } else
518 error = ENOENT; /* Nothing found */
519 return (error);
520 }
521
522 int
523 linker_reference_module(const char *modname, struct mod_depend *verinfo,
524 linker_file_t *result)
525 {
526 modlist_t mod;
527 int error;
528
529 sx_xlock(&kld_sx);
530 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) {
531 *result = mod->container;
532 (*result)->refs++;
533 sx_xunlock(&kld_sx);
534 return (0);
535 }
536
537 error = linker_load_module(NULL, modname, NULL, verinfo, result);
538 sx_xunlock(&kld_sx);
539 return (error);
540 }
541
542 int
543 linker_release_module(const char *modname, struct mod_depend *verinfo,
544 linker_file_t lf)
545 {
546 modlist_t mod;
547 int error;
548
549 sx_xlock(&kld_sx);
550 if (lf == NULL) {
551 KASSERT(modname != NULL,
552 ("linker_release_module: no file or name"));
553 mod = modlist_lookup2(modname, verinfo);
554 if (mod == NULL) {
555 sx_xunlock(&kld_sx);
556 return (ESRCH);
557 }
558 lf = mod->container;
559 } else
560 KASSERT(modname == NULL && verinfo == NULL,
561 ("linker_release_module: both file and name"));
562 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL);
563 sx_xunlock(&kld_sx);
564 return (error);
565 }
566
567 static linker_file_t
568 linker_find_file_by_name(const char *filename)
569 {
570 linker_file_t lf;
571 char *koname;
572
573 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK);
574 sprintf(koname, "%s.ko", filename);
575
576 sx_assert(&kld_sx, SA_XLOCKED);
577 TAILQ_FOREACH(lf, &linker_files, link) {
578 if (strcmp(lf->filename, koname) == 0)
579 break;
580 if (strcmp(lf->filename, filename) == 0)
581 break;
582 }
583 free(koname, M_LINKER);
584 return (lf);
585 }
586
587 static linker_file_t
588 linker_find_file_by_id(int fileid)
589 {
590 linker_file_t lf;
591
592 sx_assert(&kld_sx, SA_XLOCKED);
593 TAILQ_FOREACH(lf, &linker_files, link)
594 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED)
595 break;
596 return (lf);
597 }
598
599 int
600 linker_file_foreach(linker_predicate_t *predicate, void *context)
601 {
602 linker_file_t lf;
603 int retval = 0;
604
605 sx_xlock(&kld_sx);
606 TAILQ_FOREACH(lf, &linker_files, link) {
607 retval = predicate(lf, context);
608 if (retval != 0)
609 break;
610 }
611 sx_xunlock(&kld_sx);
612 return (retval);
613 }
614
615 linker_file_t
616 linker_make_file(const char *pathname, linker_class_t lc)
617 {
618 linker_file_t lf;
619 const char *filename;
620
621 if (!cold)
622 sx_assert(&kld_sx, SA_XLOCKED);
623 filename = linker_basename(pathname);
624
625 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname));
626 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK);
627 if (lf == NULL)
628 return (NULL);
629 lf->ctors_addr = 0;
630 lf->ctors_size = 0;
631 lf->dtors_addr = 0;
632 lf->dtors_size = 0;
633 lf->refs = 1;
634 lf->userrefs = 0;
635 lf->flags = 0;
636 lf->filename = strdup(filename, M_LINKER);
637 lf->pathname = strdup(pathname, M_LINKER);
638 LINKER_GET_NEXT_FILE_ID(lf->id);
639 lf->ndeps = 0;
640 lf->deps = NULL;
641 lf->loadcnt = ++loadcnt;
642 #ifdef __arm__
643 lf->exidx_addr = 0;
644 lf->exidx_size = 0;
645 #endif
646 STAILQ_INIT(&lf->common);
647 TAILQ_INIT(&lf->modules);
648 TAILQ_INSERT_TAIL(&linker_files, lf, link);
649 return (lf);
650 }
651
652 int
653 linker_file_unload(linker_file_t file, int flags)
654 {
655 module_t mod, next;
656 modlist_t ml, nextml;
657 struct common_symbol *cp;
658 int error, i;
659
660 /* Refuse to unload modules if securelevel raised. */
661 if (prison0.pr_securelevel > 0)
662 return (EPERM);
663
664 sx_assert(&kld_sx, SA_XLOCKED);
665 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs));
666
667 /* Easy case of just dropping a reference. */
668 if (file->refs > 1) {
669 file->refs--;
670 return (0);
671 }
672
673 /* Give eventhandlers a chance to prevent the unload. */
674 error = 0;
675 EVENTHANDLER_INVOKE(kld_unload_try, file, &error);
676 if (error != 0)
677 return (EBUSY);
678
679 KLD_DPF(FILE, ("linker_file_unload: file is unloading,"
680 " informing modules\n"));
681
682 /*
683 * Quiesce all the modules to give them a chance to veto the unload.
684 */
685 MOD_SLOCK;
686 for (mod = TAILQ_FIRST(&file->modules); mod;
687 mod = module_getfnext(mod)) {
688 error = module_quiesce(mod);
689 if (error != 0 && flags != LINKER_UNLOAD_FORCE) {
690 KLD_DPF(FILE, ("linker_file_unload: module %s"
691 " vetoed unload\n", module_getname(mod)));
692 /*
693 * XXX: Do we need to tell all the quiesced modules
694 * that they can resume work now via a new module
695 * event?
696 */
697 MOD_SUNLOCK;
698 return (error);
699 }
700 }
701 MOD_SUNLOCK;
702
703 /*
704 * Inform any modules associated with this file that they are
705 * being unloaded.
706 */
707 MOD_XLOCK;
708 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) {
709 next = module_getfnext(mod);
710 MOD_XUNLOCK;
711
712 /*
713 * Give the module a chance to veto the unload.
714 */
715 if ((error = module_unload(mod)) != 0) {
716 #ifdef KLD_DEBUG
717 MOD_SLOCK;
718 KLD_DPF(FILE, ("linker_file_unload: module %s"
719 " failed unload\n", module_getname(mod)));
720 MOD_SUNLOCK;
721 #endif
722 return (error);
723 }
724 MOD_XLOCK;
725 module_release(mod);
726 }
727 MOD_XUNLOCK;
728
729 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) {
730 if (ml->container == file) {
731 TAILQ_REMOVE(&found_modules, ml, link);
732 free(ml, M_LINKER);
733 }
734 }
735
736 /*
737 * Don't try to run SYSUNINITs if we are unloaded due to a
738 * link error.
739 */
740 if (file->flags & LINKER_FILE_LINKED) {
741 file->flags &= ~LINKER_FILE_LINKED;
742 linker_file_unregister_sysctls(file);
743 linker_file_sysuninit(file);
744 }
745 TAILQ_REMOVE(&linker_files, file, link);
746
747 if (file->deps) {
748 for (i = 0; i < file->ndeps; i++)
749 linker_file_unload(file->deps[i], flags);
750 free(file->deps, M_LINKER);
751 file->deps = NULL;
752 }
753 while ((cp = STAILQ_FIRST(&file->common)) != NULL) {
754 STAILQ_REMOVE_HEAD(&file->common, link);
755 free(cp, M_LINKER);
756 }
757
758 LINKER_UNLOAD(file);
759
760 EVENTHANDLER_INVOKE(kld_unload, file->filename, file->address,
761 file->size);
762
763 if (file->filename) {
764 free(file->filename, M_LINKER);
765 file->filename = NULL;
766 }
767 if (file->pathname) {
768 free(file->pathname, M_LINKER);
769 file->pathname = NULL;
770 }
771 kobj_delete((kobj_t) file, M_LINKER);
772 return (0);
773 }
774
775 int
776 linker_ctf_get(linker_file_t file, linker_ctf_t *lc)
777 {
778 return (LINKER_CTF_GET(file, lc));
779 }
780
781 static int
782 linker_file_add_dependency(linker_file_t file, linker_file_t dep)
783 {
784 linker_file_t *newdeps;
785
786 sx_assert(&kld_sx, SA_XLOCKED);
787 file->deps = realloc(file->deps, (file->ndeps + 1) * sizeof(*newdeps),
788 M_LINKER, M_WAITOK | M_ZERO);
789 file->deps[file->ndeps] = dep;
790 file->ndeps++;
791 KLD_DPF(FILE, ("linker_file_add_dependency:"
792 " adding %s as dependency for %s\n",
793 dep->filename, file->filename));
794 return (0);
795 }
796
797 /*
798 * Locate a linker set and its contents. This is a helper function to avoid
799 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **.
800 * This function is used in this file so we can avoid having lots of (void **)
801 * casts.
802 */
803 int
804 linker_file_lookup_set(linker_file_t file, const char *name,
805 void *firstp, void *lastp, int *countp)
806 {
807
808 sx_assert(&kld_sx, SA_LOCKED);
809 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp));
810 }
811
812 /*
813 * List all functions in a file.
814 */
815 int
816 linker_file_function_listall(linker_file_t lf,
817 linker_function_nameval_callback_t callback_func, void *arg)
818 {
819 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg));
820 }
821
822 caddr_t
823 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps)
824 {
825 caddr_t sym;
826 int locked;
827
828 locked = sx_xlocked(&kld_sx);
829 if (!locked)
830 sx_xlock(&kld_sx);
831 sym = linker_file_lookup_symbol_internal(file, name, deps);
832 if (!locked)
833 sx_xunlock(&kld_sx);
834 return (sym);
835 }
836
837 static caddr_t
838 linker_file_lookup_symbol_internal(linker_file_t file, const char *name,
839 int deps)
840 {
841 c_linker_sym_t sym;
842 linker_symval_t symval;
843 caddr_t address;
844 size_t common_size = 0;
845 int i;
846
847 sx_assert(&kld_sx, SA_XLOCKED);
848 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n",
849 file, name, deps));
850
851 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) {
852 LINKER_SYMBOL_VALUES(file, sym, &symval);
853 if (symval.value == 0)
854 /*
855 * For commons, first look them up in the
856 * dependencies and only allocate space if not found
857 * there.
858 */
859 common_size = symval.size;
860 else {
861 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol"
862 ".value=%p\n", symval.value));
863 return (symval.value);
864 }
865 }
866 if (deps) {
867 for (i = 0; i < file->ndeps; i++) {
868 address = linker_file_lookup_symbol_internal(
869 file->deps[i], name, 0);
870 if (address) {
871 KLD_DPF(SYM, ("linker_file_lookup_symbol:"
872 " deps value=%p\n", address));
873 return (address);
874 }
875 }
876 }
877 if (common_size > 0) {
878 /*
879 * This is a common symbol which was not found in the
880 * dependencies. We maintain a simple common symbol table in
881 * the file object.
882 */
883 struct common_symbol *cp;
884
885 STAILQ_FOREACH(cp, &file->common, link) {
886 if (strcmp(cp->name, name) == 0) {
887 KLD_DPF(SYM, ("linker_file_lookup_symbol:"
888 " old common value=%p\n", cp->address));
889 return (cp->address);
890 }
891 }
892 /*
893 * Round the symbol size up to align.
894 */
895 common_size = (common_size + sizeof(int) - 1) & -sizeof(int);
896 cp = malloc(sizeof(struct common_symbol)
897 + common_size + strlen(name) + 1, M_LINKER,
898 M_WAITOK | M_ZERO);
899 cp->address = (caddr_t)(cp + 1);
900 cp->name = cp->address + common_size;
901 strcpy(cp->name, name);
902 bzero(cp->address, common_size);
903 STAILQ_INSERT_TAIL(&file->common, cp, link);
904
905 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common"
906 " value=%p\n", cp->address));
907 return (cp->address);
908 }
909 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n"));
910 return (0);
911 }
912
913 /*
914 * Both DDB and stack(9) rely on the kernel linker to provide forward and
915 * backward lookup of symbols. However, DDB and sometimes stack(9) need to
916 * do this in a lockfree manner. We provide a set of internal helper
917 * routines to perform these operations without locks, and then wrappers that
918 * optionally lock.
919 *
920 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB.
921 */
922 #ifdef DDB
923 static int
924 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym)
925 {
926 linker_file_t lf;
927
928 TAILQ_FOREACH(lf, &linker_files, link) {
929 if (LINKER_LOOKUP_DEBUG_SYMBOL(lf, symstr, sym) == 0)
930 return (0);
931 }
932 return (ENOENT);
933 }
934 #endif
935
936 static int
937 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
938 {
939 linker_file_t lf;
940 c_linker_sym_t best, es;
941 u_long diff, bestdiff, off;
942
943 best = 0;
944 off = (uintptr_t)value;
945 bestdiff = off;
946 TAILQ_FOREACH(lf, &linker_files, link) {
947 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0)
948 continue;
949 if (es != 0 && diff < bestdiff) {
950 best = es;
951 bestdiff = diff;
952 }
953 if (bestdiff == 0)
954 break;
955 }
956 if (best) {
957 *sym = best;
958 *diffp = bestdiff;
959 return (0);
960 } else {
961 *sym = 0;
962 *diffp = off;
963 return (ENOENT);
964 }
965 }
966
967 static int
968 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
969 {
970 linker_file_t lf;
971
972 TAILQ_FOREACH(lf, &linker_files, link) {
973 if (LINKER_DEBUG_SYMBOL_VALUES(lf, sym, symval) == 0)
974 return (0);
975 }
976 return (ENOENT);
977 }
978
979 static int
980 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen,
981 long *offset)
982 {
983 linker_symval_t symval;
984 c_linker_sym_t sym;
985 int error;
986
987 *offset = 0;
988 error = linker_debug_search_symbol(value, &sym, offset);
989 if (error)
990 return (error);
991 error = linker_debug_symbol_values(sym, &symval);
992 if (error)
993 return (error);
994 strlcpy(buf, symval.name, buflen);
995 return (0);
996 }
997
998 /*
999 * DDB Helpers. DDB has to look across multiple files with their own symbol
1000 * tables and string tables.
1001 *
1002 * Note that we do not obey list locking protocols here. We really don't need
1003 * DDB to hang because somebody's got the lock held. We'll take the chance
1004 * that the files list is inconsistent instead.
1005 */
1006 #ifdef DDB
1007 int
1008 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym)
1009 {
1010
1011 return (linker_debug_lookup(symstr, sym));
1012 }
1013 #endif
1014
1015 int
1016 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
1017 {
1018
1019 return (linker_debug_search_symbol(value, sym, diffp));
1020 }
1021
1022 int
1023 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
1024 {
1025
1026 return (linker_debug_symbol_values(sym, symval));
1027 }
1028
1029 int
1030 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen,
1031 long *offset)
1032 {
1033
1034 return (linker_debug_search_symbol_name(value, buf, buflen, offset));
1035 }
1036
1037 /*
1038 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do
1039 * obey locking protocols, and offer a significantly less complex interface.
1040 */
1041 int
1042 linker_search_symbol_name_flags(caddr_t value, char *buf, u_int buflen,
1043 long *offset, int flags)
1044 {
1045 int error;
1046
1047 KASSERT((flags & (M_NOWAIT | M_WAITOK)) != 0 &&
1048 (flags & (M_NOWAIT | M_WAITOK)) != (M_NOWAIT | M_WAITOK),
1049 ("%s: bad flags: 0x%x", __func__, flags));
1050
1051 if (flags & M_NOWAIT) {
1052 if (!sx_try_slock(&kld_sx))
1053 return (EWOULDBLOCK);
1054 } else
1055 sx_slock(&kld_sx);
1056
1057 error = linker_debug_search_symbol_name(value, buf, buflen, offset);
1058 sx_sunlock(&kld_sx);
1059 return (error);
1060 }
1061
1062 int
1063 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen,
1064 long *offset)
1065 {
1066
1067 return (linker_search_symbol_name_flags(value, buf, buflen, offset,
1068 M_WAITOK));
1069 }
1070
1071 int
1072 linker_kldload_busy(int flags)
1073 {
1074 int error;
1075
1076 MPASS((flags & ~(LINKER_UB_UNLOCK | LINKER_UB_LOCKED |
1077 LINKER_UB_PCATCH)) == 0);
1078 if ((flags & LINKER_UB_LOCKED) != 0)
1079 sx_assert(&kld_sx, SA_XLOCKED);
1080
1081 if ((flags & LINKER_UB_LOCKED) == 0)
1082 sx_xlock(&kld_sx);
1083 while (kld_busy > 0) {
1084 if (kld_busy_owner == curthread)
1085 break;
1086 error = sx_sleep(&kld_busy, &kld_sx,
1087 (flags & LINKER_UB_PCATCH) != 0 ? PCATCH : 0,
1088 "kldbusy", 0);
1089 if (error != 0) {
1090 if ((flags & LINKER_UB_UNLOCK) != 0)
1091 sx_xunlock(&kld_sx);
1092 return (error);
1093 }
1094 }
1095 kld_busy++;
1096 kld_busy_owner = curthread;
1097 if ((flags & LINKER_UB_UNLOCK) != 0)
1098 sx_xunlock(&kld_sx);
1099 return (0);
1100 }
1101
1102 void
1103 linker_kldload_unbusy(int flags)
1104 {
1105 MPASS((flags & ~LINKER_UB_LOCKED) == 0);
1106 if ((flags & LINKER_UB_LOCKED) != 0)
1107 sx_assert(&kld_sx, SA_XLOCKED);
1108
1109 if ((flags & LINKER_UB_LOCKED) == 0)
1110 sx_xlock(&kld_sx);
1111 MPASS(kld_busy > 0);
1112 if (kld_busy_owner != curthread)
1113 panic("linker_kldload_unbusy done by not owning thread %p",
1114 kld_busy_owner);
1115 kld_busy--;
1116 if (kld_busy == 0) {
1117 kld_busy_owner = NULL;
1118 wakeup(&kld_busy);
1119 }
1120 sx_xunlock(&kld_sx);
1121 }
1122
1123 /*
1124 * Syscalls.
1125 */
1126 int
1127 kern_kldload(struct thread *td, const char *file, int *fileid)
1128 {
1129 const char *kldname, *modname;
1130 linker_file_t lf;
1131 int error;
1132
1133 if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
1134 return (error);
1135
1136 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0)
1137 return (error);
1138
1139 /*
1140 * If file does not contain a qualified name or any dot in it
1141 * (kldname.ko, or kldname.ver.ko) treat it as an interface
1142 * name.
1143 */
1144 if (strchr(file, '/') || strchr(file, '.')) {
1145 kldname = file;
1146 modname = NULL;
1147 } else {
1148 kldname = NULL;
1149 modname = file;
1150 }
1151
1152 error = linker_kldload_busy(LINKER_UB_PCATCH);
1153 if (error != 0) {
1154 sx_xunlock(&kld_sx);
1155 return (error);
1156 }
1157
1158 /*
1159 * It is possible that kldloaded module will attach a new ifnet,
1160 * so vnet context must be set when this ocurs.
1161 */
1162 CURVNET_SET(TD_TO_VNET(td));
1163
1164 error = linker_load_module(kldname, modname, NULL, NULL, &lf);
1165 CURVNET_RESTORE();
1166
1167 if (error == 0) {
1168 lf->userrefs++;
1169 if (fileid != NULL)
1170 *fileid = lf->id;
1171 }
1172 linker_kldload_unbusy(LINKER_UB_LOCKED);
1173 return (error);
1174 }
1175
1176 int
1177 sys_kldload(struct thread *td, struct kldload_args *uap)
1178 {
1179 char *pathname = NULL;
1180 int error, fileid;
1181
1182 td->td_retval[0] = -1;
1183
1184 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1185 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL);
1186 if (error == 0) {
1187 error = kern_kldload(td, pathname, &fileid);
1188 if (error == 0)
1189 td->td_retval[0] = fileid;
1190 }
1191 free(pathname, M_TEMP);
1192 return (error);
1193 }
1194
1195 int
1196 kern_kldunload(struct thread *td, int fileid, int flags)
1197 {
1198 linker_file_t lf;
1199 int error = 0;
1200
1201 if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
1202 return (error);
1203
1204 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0)
1205 return (error);
1206
1207 error = linker_kldload_busy(LINKER_UB_PCATCH);
1208 if (error != 0) {
1209 sx_xunlock(&kld_sx);
1210 return (error);
1211 }
1212
1213 CURVNET_SET(TD_TO_VNET(td));
1214 lf = linker_find_file_by_id(fileid);
1215 if (lf) {
1216 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs));
1217
1218 if (lf->userrefs == 0) {
1219 /*
1220 * XXX: maybe LINKER_UNLOAD_FORCE should override ?
1221 */
1222 printf("kldunload: attempt to unload file that was"
1223 " loaded by the kernel\n");
1224 error = EBUSY;
1225 } else {
1226 lf->userrefs--;
1227 error = linker_file_unload(lf, flags);
1228 if (error)
1229 lf->userrefs++;
1230 }
1231 } else
1232 error = ENOENT;
1233 CURVNET_RESTORE();
1234 linker_kldload_unbusy(LINKER_UB_LOCKED);
1235 return (error);
1236 }
1237
1238 int
1239 sys_kldunload(struct thread *td, struct kldunload_args *uap)
1240 {
1241
1242 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL));
1243 }
1244
1245 int
1246 sys_kldunloadf(struct thread *td, struct kldunloadf_args *uap)
1247 {
1248
1249 if (uap->flags != LINKER_UNLOAD_NORMAL &&
1250 uap->flags != LINKER_UNLOAD_FORCE)
1251 return (EINVAL);
1252 return (kern_kldunload(td, uap->fileid, uap->flags));
1253 }
1254
1255 int
1256 sys_kldfind(struct thread *td, struct kldfind_args *uap)
1257 {
1258 char *pathname;
1259 const char *filename;
1260 linker_file_t lf;
1261 int error;
1262
1263 #ifdef MAC
1264 error = mac_kld_check_stat(td->td_ucred);
1265 if (error)
1266 return (error);
1267 #endif
1268
1269 td->td_retval[0] = -1;
1270
1271 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1272 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0)
1273 goto out;
1274
1275 filename = linker_basename(pathname);
1276 sx_xlock(&kld_sx);
1277 lf = linker_find_file_by_name(filename);
1278 if (lf)
1279 td->td_retval[0] = lf->id;
1280 else
1281 error = ENOENT;
1282 sx_xunlock(&kld_sx);
1283 out:
1284 free(pathname, M_TEMP);
1285 return (error);
1286 }
1287
1288 int
1289 sys_kldnext(struct thread *td, struct kldnext_args *uap)
1290 {
1291 linker_file_t lf;
1292 int error = 0;
1293
1294 #ifdef MAC
1295 error = mac_kld_check_stat(td->td_ucred);
1296 if (error)
1297 return (error);
1298 #endif
1299
1300 sx_xlock(&kld_sx);
1301 if (uap->fileid == 0)
1302 lf = TAILQ_FIRST(&linker_files);
1303 else {
1304 lf = linker_find_file_by_id(uap->fileid);
1305 if (lf == NULL) {
1306 error = ENOENT;
1307 goto out;
1308 }
1309 lf = TAILQ_NEXT(lf, link);
1310 }
1311
1312 /* Skip partially loaded files. */
1313 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED))
1314 lf = TAILQ_NEXT(lf, link);
1315
1316 if (lf)
1317 td->td_retval[0] = lf->id;
1318 else
1319 td->td_retval[0] = 0;
1320 out:
1321 sx_xunlock(&kld_sx);
1322 return (error);
1323 }
1324
1325 int
1326 sys_kldstat(struct thread *td, struct kldstat_args *uap)
1327 {
1328 struct kld_file_stat *stat;
1329 int error, version;
1330
1331 /*
1332 * Check the version of the user's structure.
1333 */
1334 if ((error = copyin(&uap->stat->version, &version, sizeof(version)))
1335 != 0)
1336 return (error);
1337 if (version != sizeof(struct kld_file_stat_1) &&
1338 version != sizeof(struct kld_file_stat))
1339 return (EINVAL);
1340
1341 stat = malloc(sizeof(*stat), M_TEMP, M_WAITOK | M_ZERO);
1342 error = kern_kldstat(td, uap->fileid, stat);
1343 if (error == 0)
1344 error = copyout(stat, uap->stat, version);
1345 free(stat, M_TEMP);
1346 return (error);
1347 }
1348
1349 int
1350 kern_kldstat(struct thread *td, int fileid, struct kld_file_stat *stat)
1351 {
1352 linker_file_t lf;
1353 int namelen;
1354 #ifdef MAC
1355 int error;
1356
1357 error = mac_kld_check_stat(td->td_ucred);
1358 if (error)
1359 return (error);
1360 #endif
1361
1362 sx_xlock(&kld_sx);
1363 lf = linker_find_file_by_id(fileid);
1364 if (lf == NULL) {
1365 sx_xunlock(&kld_sx);
1366 return (ENOENT);
1367 }
1368
1369 /* Version 1 fields: */
1370 namelen = strlen(lf->filename) + 1;
1371 if (namelen > sizeof(stat->name))
1372 namelen = sizeof(stat->name);
1373 bcopy(lf->filename, &stat->name[0], namelen);
1374 stat->refs = lf->refs;
1375 stat->id = lf->id;
1376 stat->address = lf->address;
1377 stat->size = lf->size;
1378 /* Version 2 fields: */
1379 namelen = strlen(lf->pathname) + 1;
1380 if (namelen > sizeof(stat->pathname))
1381 namelen = sizeof(stat->pathname);
1382 bcopy(lf->pathname, &stat->pathname[0], namelen);
1383 sx_xunlock(&kld_sx);
1384
1385 td->td_retval[0] = 0;
1386 return (0);
1387 }
1388
1389 #ifdef DDB
1390 DB_COMMAND_FLAGS(kldstat, db_kldstat, DB_CMD_MEMSAFE)
1391 {
1392 linker_file_t lf;
1393
1394 #define POINTER_WIDTH ((int)(sizeof(void *) * 2 + 2))
1395 db_printf("Id Refs Address%*c Size Name\n", POINTER_WIDTH - 7, ' ');
1396 #undef POINTER_WIDTH
1397 TAILQ_FOREACH(lf, &linker_files, link) {
1398 if (db_pager_quit)
1399 return;
1400 db_printf("%2d %4d %p %-8zx %s\n", lf->id, lf->refs,
1401 lf->address, lf->size, lf->filename);
1402 }
1403 }
1404 #endif /* DDB */
1405
1406 int
1407 sys_kldfirstmod(struct thread *td, struct kldfirstmod_args *uap)
1408 {
1409 linker_file_t lf;
1410 module_t mp;
1411 int error = 0;
1412
1413 #ifdef MAC
1414 error = mac_kld_check_stat(td->td_ucred);
1415 if (error)
1416 return (error);
1417 #endif
1418
1419 sx_xlock(&kld_sx);
1420 lf = linker_find_file_by_id(uap->fileid);
1421 if (lf) {
1422 MOD_SLOCK;
1423 mp = TAILQ_FIRST(&lf->modules);
1424 if (mp != NULL)
1425 td->td_retval[0] = module_getid(mp);
1426 else
1427 td->td_retval[0] = 0;
1428 MOD_SUNLOCK;
1429 } else
1430 error = ENOENT;
1431 sx_xunlock(&kld_sx);
1432 return (error);
1433 }
1434
1435 int
1436 sys_kldsym(struct thread *td, struct kldsym_args *uap)
1437 {
1438 char *symstr = NULL;
1439 c_linker_sym_t sym;
1440 linker_symval_t symval;
1441 linker_file_t lf;
1442 struct kld_sym_lookup lookup;
1443 int error = 0;
1444
1445 #ifdef MAC
1446 error = mac_kld_check_stat(td->td_ucred);
1447 if (error)
1448 return (error);
1449 #endif
1450
1451 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0)
1452 return (error);
1453 if (lookup.version != sizeof(lookup) ||
1454 uap->cmd != KLDSYM_LOOKUP)
1455 return (EINVAL);
1456 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1457 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0)
1458 goto out;
1459 sx_xlock(&kld_sx);
1460 if (uap->fileid != 0) {
1461 lf = linker_find_file_by_id(uap->fileid);
1462 if (lf == NULL)
1463 error = ENOENT;
1464 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
1465 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
1466 lookup.symvalue = (uintptr_t) symval.value;
1467 lookup.symsize = symval.size;
1468 error = copyout(&lookup, uap->data, sizeof(lookup));
1469 } else
1470 error = ENOENT;
1471 } else {
1472 TAILQ_FOREACH(lf, &linker_files, link) {
1473 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
1474 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
1475 lookup.symvalue = (uintptr_t)symval.value;
1476 lookup.symsize = symval.size;
1477 error = copyout(&lookup, uap->data,
1478 sizeof(lookup));
1479 break;
1480 }
1481 }
1482 if (lf == NULL)
1483 error = ENOENT;
1484 }
1485 sx_xunlock(&kld_sx);
1486 out:
1487 free(symstr, M_TEMP);
1488 return (error);
1489 }
1490
1491 /*
1492 * Preloaded module support
1493 */
1494
1495 static modlist_t
1496 modlist_lookup(const char *name, int ver)
1497 {
1498 modlist_t mod;
1499
1500 TAILQ_FOREACH(mod, &found_modules, link) {
1501 if (strcmp(mod->name, name) == 0 &&
1502 (ver == 0 || mod->version == ver))
1503 return (mod);
1504 }
1505 return (NULL);
1506 }
1507
1508 static modlist_t
1509 modlist_lookup2(const char *name, const struct mod_depend *verinfo)
1510 {
1511 modlist_t mod, bestmod;
1512 int ver;
1513
1514 if (verinfo == NULL)
1515 return (modlist_lookup(name, 0));
1516 bestmod = NULL;
1517 TAILQ_FOREACH(mod, &found_modules, link) {
1518 if (strcmp(mod->name, name) != 0)
1519 continue;
1520 ver = mod->version;
1521 if (ver == verinfo->md_ver_preferred)
1522 return (mod);
1523 if (ver >= verinfo->md_ver_minimum &&
1524 ver <= verinfo->md_ver_maximum &&
1525 (bestmod == NULL || ver > bestmod->version))
1526 bestmod = mod;
1527 }
1528 return (bestmod);
1529 }
1530
1531 static modlist_t
1532 modlist_newmodule(const char *modname, int version, linker_file_t container)
1533 {
1534 modlist_t mod;
1535
1536 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO);
1537 if (mod == NULL)
1538 panic("no memory for module list");
1539 mod->container = container;
1540 mod->name = modname;
1541 mod->version = version;
1542 TAILQ_INSERT_TAIL(&found_modules, mod, link);
1543 return (mod);
1544 }
1545
1546 static void
1547 linker_addmodules(linker_file_t lf, struct mod_metadata **start,
1548 struct mod_metadata **stop, int preload)
1549 {
1550 struct mod_metadata *mp, **mdp;
1551 const char *modname;
1552 int ver;
1553
1554 for (mdp = start; mdp < stop; mdp++) {
1555 mp = *mdp;
1556 if (mp->md_type != MDT_VERSION)
1557 continue;
1558 modname = mp->md_cval;
1559 ver = ((const struct mod_version *)mp->md_data)->mv_version;
1560 if (modlist_lookup(modname, ver) != NULL) {
1561 printf("module %s already present!\n", modname);
1562 /* XXX what can we do? this is a build error. :-( */
1563 continue;
1564 }
1565 modlist_newmodule(modname, ver, lf);
1566 }
1567 }
1568
1569 static void
1570 linker_preload(void *arg)
1571 {
1572 caddr_t modptr;
1573 const char *modname, *nmodname;
1574 char *modtype;
1575 linker_file_t lf, nlf;
1576 linker_class_t lc;
1577 int error;
1578 linker_file_list_t loaded_files;
1579 linker_file_list_t depended_files;
1580 struct mod_metadata *mp, *nmp;
1581 struct mod_metadata **start, **stop, **mdp, **nmdp;
1582 const struct mod_depend *verinfo;
1583 int nver;
1584 int resolves;
1585 modlist_t mod;
1586 struct sysinit **si_start, **si_stop;
1587
1588 TAILQ_INIT(&loaded_files);
1589 TAILQ_INIT(&depended_files);
1590 TAILQ_INIT(&found_modules);
1591 error = 0;
1592
1593 modptr = NULL;
1594 sx_xlock(&kld_sx);
1595 while ((modptr = preload_search_next_name(modptr)) != NULL) {
1596 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
1597 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE);
1598 if (modname == NULL) {
1599 printf("Preloaded module at %p does not have a"
1600 " name!\n", modptr);
1601 continue;
1602 }
1603 if (modtype == NULL) {
1604 printf("Preloaded module at %p does not have a type!\n",
1605 modptr);
1606 continue;
1607 }
1608 if (bootverbose)
1609 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname,
1610 modptr);
1611 lf = NULL;
1612 TAILQ_FOREACH(lc, &classes, link) {
1613 error = LINKER_LINK_PRELOAD(lc, modname, &lf);
1614 if (!error)
1615 break;
1616 lf = NULL;
1617 }
1618 if (lf)
1619 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded);
1620 }
1621
1622 /*
1623 * First get a list of stuff in the kernel.
1624 */
1625 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start,
1626 &stop, NULL) == 0)
1627 linker_addmodules(linker_kernel_file, start, stop, 1);
1628
1629 /*
1630 * This is a once-off kinky bubble sort to resolve relocation
1631 * dependency requirements.
1632 */
1633 restart:
1634 TAILQ_FOREACH(lf, &loaded_files, loaded) {
1635 error = linker_file_lookup_set(lf, MDT_SETNAME, &start,
1636 &stop, NULL);
1637 /*
1638 * First, look to see if we would successfully link with this
1639 * stuff.
1640 */
1641 resolves = 1; /* unless we know otherwise */
1642 if (!error) {
1643 for (mdp = start; mdp < stop; mdp++) {
1644 mp = *mdp;
1645 if (mp->md_type != MDT_DEPEND)
1646 continue;
1647 modname = mp->md_cval;
1648 verinfo = mp->md_data;
1649 for (nmdp = start; nmdp < stop; nmdp++) {
1650 nmp = *nmdp;
1651 if (nmp->md_type != MDT_VERSION)
1652 continue;
1653 nmodname = nmp->md_cval;
1654 if (strcmp(modname, nmodname) == 0)
1655 break;
1656 }
1657 if (nmdp < stop) /* it's a self reference */
1658 continue;
1659
1660 /*
1661 * ok, the module isn't here yet, we
1662 * are not finished
1663 */
1664 if (modlist_lookup2(modname, verinfo) == NULL)
1665 resolves = 0;
1666 }
1667 }
1668 /*
1669 * OK, if we found our modules, we can link. So, "provide"
1670 * the modules inside and add it to the end of the link order
1671 * list.
1672 */
1673 if (resolves) {
1674 if (!error) {
1675 for (mdp = start; mdp < stop; mdp++) {
1676 mp = *mdp;
1677 if (mp->md_type != MDT_VERSION)
1678 continue;
1679 modname = mp->md_cval;
1680 nver = ((const struct mod_version *)
1681 mp->md_data)->mv_version;
1682 if (modlist_lookup(modname,
1683 nver) != NULL) {
1684 printf("module %s already"
1685 " present!\n", modname);
1686 TAILQ_REMOVE(&loaded_files,
1687 lf, loaded);
1688 linker_file_unload(lf,
1689 LINKER_UNLOAD_FORCE);
1690 /* we changed tailq next ptr */
1691 goto restart;
1692 }
1693 modlist_newmodule(modname, nver, lf);
1694 }
1695 }
1696 TAILQ_REMOVE(&loaded_files, lf, loaded);
1697 TAILQ_INSERT_TAIL(&depended_files, lf, loaded);
1698 /*
1699 * Since we provided modules, we need to restart the
1700 * sort so that the previous files that depend on us
1701 * have a chance. Also, we've busted the tailq next
1702 * pointer with the REMOVE.
1703 */
1704 goto restart;
1705 }
1706 }
1707
1708 /*
1709 * At this point, we check to see what could not be resolved..
1710 */
1711 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) {
1712 TAILQ_REMOVE(&loaded_files, lf, loaded);
1713 printf("KLD file %s is missing dependencies\n", lf->filename);
1714 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1715 }
1716
1717 /*
1718 * We made it. Finish off the linking in the order we determined.
1719 */
1720 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) {
1721 if (linker_kernel_file) {
1722 linker_kernel_file->refs++;
1723 error = linker_file_add_dependency(lf,
1724 linker_kernel_file);
1725 if (error)
1726 panic("cannot add dependency");
1727 }
1728 error = linker_file_lookup_set(lf, MDT_SETNAME, &start,
1729 &stop, NULL);
1730 if (!error) {
1731 for (mdp = start; mdp < stop; mdp++) {
1732 mp = *mdp;
1733 if (mp->md_type != MDT_DEPEND)
1734 continue;
1735 modname = mp->md_cval;
1736 verinfo = mp->md_data;
1737 mod = modlist_lookup2(modname, verinfo);
1738 if (mod == NULL) {
1739 printf("KLD file %s - cannot find "
1740 "dependency \"%s\"\n",
1741 lf->filename, modname);
1742 goto fail;
1743 }
1744 /* Don't count self-dependencies */
1745 if (lf == mod->container)
1746 continue;
1747 mod->container->refs++;
1748 error = linker_file_add_dependency(lf,
1749 mod->container);
1750 if (error)
1751 panic("cannot add dependency");
1752 }
1753 }
1754 /*
1755 * Now do relocation etc using the symbol search paths
1756 * established by the dependencies
1757 */
1758 error = LINKER_LINK_PRELOAD_FINISH(lf);
1759 if (error) {
1760 printf("KLD file %s - could not finalize loading\n",
1761 lf->filename);
1762 goto fail;
1763 }
1764 linker_file_register_modules(lf);
1765 if (!TAILQ_EMPTY(&lf->modules))
1766 lf->flags |= LINKER_FILE_MODULES;
1767 if (linker_file_lookup_set(lf, "sysinit_set", &si_start,
1768 &si_stop, NULL) == 0)
1769 sysinit_add(si_start, si_stop);
1770 linker_file_register_sysctls(lf, true);
1771 lf->flags |= LINKER_FILE_LINKED;
1772 continue;
1773 fail:
1774 TAILQ_REMOVE(&depended_files, lf, loaded);
1775 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1776 }
1777 sx_xunlock(&kld_sx);
1778 /* woohoo! we made it! */
1779 }
1780
1781 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, NULL);
1782
1783 /*
1784 * Handle preload files that failed to load any modules.
1785 */
1786 static void
1787 linker_preload_finish(void *arg)
1788 {
1789 linker_file_t lf, nlf;
1790
1791 sx_xlock(&kld_sx);
1792 TAILQ_FOREACH_SAFE(lf, &linker_files, link, nlf) {
1793 /*
1794 * If all of the modules in this file failed to load, unload
1795 * the file and return an error of ENOEXEC. (Parity with
1796 * linker_load_file.)
1797 */
1798 if ((lf->flags & LINKER_FILE_MODULES) != 0 &&
1799 TAILQ_EMPTY(&lf->modules)) {
1800 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1801 continue;
1802 }
1803
1804 lf->flags &= ~LINKER_FILE_MODULES;
1805 lf->userrefs++; /* so we can (try to) kldunload it */
1806 }
1807 sx_xunlock(&kld_sx);
1808 }
1809
1810 /*
1811 * Attempt to run after all DECLARE_MODULE SYSINITs. Unfortunately they can be
1812 * scheduled at any subsystem and order, so run this as late as possible. init
1813 * becomes runnable in SI_SUB_KTHREAD_INIT, so go slightly before that.
1814 */
1815 SYSINIT(preload_finish, SI_SUB_KTHREAD_INIT - 100, SI_ORDER_MIDDLE,
1816 linker_preload_finish, NULL);
1817
1818 /*
1819 * Search for a not-loaded module by name.
1820 *
1821 * Modules may be found in the following locations:
1822 *
1823 * - preloaded (result is just the module name) - on disk (result is full path
1824 * to module)
1825 *
1826 * If the module name is qualified in any way (contains path, etc.) the we
1827 * simply return a copy of it.
1828 *
1829 * The search path can be manipulated via sysctl. Note that we use the ';'
1830 * character as a separator to be consistent with the bootloader.
1831 */
1832
1833 static char linker_hintfile[] = "linker.hints";
1834 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules";
1835
1836 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RWTUN, linker_path,
1837 sizeof(linker_path), "module load search path");
1838
1839 TUNABLE_STR("module_path", linker_path, sizeof(linker_path));
1840
1841 static const char * const linker_ext_list[] = {
1842 "",
1843 ".ko",
1844 NULL
1845 };
1846
1847 /*
1848 * Check if file actually exists either with or without extension listed in
1849 * the linker_ext_list. (probably should be generic for the rest of the
1850 * kernel)
1851 */
1852 static char *
1853 linker_lookup_file(const char *path, int pathlen, const char *name,
1854 int namelen, struct vattr *vap)
1855 {
1856 struct nameidata nd;
1857 struct thread *td = curthread; /* XXX */
1858 const char * const *cpp, *sep;
1859 char *result;
1860 int error, len, extlen, reclen, flags;
1861 enum vtype type;
1862
1863 extlen = 0;
1864 for (cpp = linker_ext_list; *cpp; cpp++) {
1865 len = strlen(*cpp);
1866 if (len > extlen)
1867 extlen = len;
1868 }
1869 extlen++; /* trailing '\0' */
1870 sep = (path[pathlen - 1] != '/') ? "/" : "";
1871
1872 reclen = pathlen + strlen(sep) + namelen + extlen + 1;
1873 result = malloc(reclen, M_LINKER, M_WAITOK);
1874 for (cpp = linker_ext_list; *cpp; cpp++) {
1875 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep,
1876 namelen, name, *cpp);
1877 /*
1878 * Attempt to open the file, and return the path if
1879 * we succeed and it's a regular file.
1880 */
1881 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result);
1882 flags = FREAD;
1883 error = vn_open(&nd, &flags, 0, NULL);
1884 if (error == 0) {
1885 NDFREE_PNBUF(&nd);
1886 type = nd.ni_vp->v_type;
1887 if (vap)
1888 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred);
1889 VOP_UNLOCK(nd.ni_vp);
1890 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
1891 if (type == VREG)
1892 return (result);
1893 }
1894 }
1895 free(result, M_LINKER);
1896 return (NULL);
1897 }
1898
1899 #define INT_ALIGN(base, ptr) ptr = \
1900 (base) + roundup2((ptr) - (base), sizeof(int))
1901
1902 /*
1903 * Lookup KLD which contains requested module in the "linker.hints" file. If
1904 * version specification is available, then try to find the best KLD.
1905 * Otherwise just find the latest one.
1906 */
1907 static char *
1908 linker_hints_lookup(const char *path, int pathlen, const char *modname,
1909 int modnamelen, const struct mod_depend *verinfo)
1910 {
1911 struct thread *td = curthread; /* XXX */
1912 struct ucred *cred = td ? td->td_ucred : NULL;
1913 struct nameidata nd;
1914 struct vattr vattr, mattr;
1915 const char *best, *sep;
1916 u_char *hints = NULL;
1917 u_char *cp, *recptr, *bufend, *result, *pathbuf;
1918 int error, ival, bestver, *intp, found, flags, clen, blen;
1919 ssize_t reclen;
1920
1921 result = NULL;
1922 bestver = found = 0;
1923
1924 sep = (path[pathlen - 1] != '/') ? "/" : "";
1925 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen +
1926 strlen(sep) + 1;
1927 pathbuf = malloc(reclen, M_LINKER, M_WAITOK);
1928 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep,
1929 linker_hintfile);
1930
1931 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf);
1932 flags = FREAD;
1933 error = vn_open(&nd, &flags, 0, NULL);
1934 if (error)
1935 goto bad;
1936 NDFREE_PNBUF(&nd);
1937 if (nd.ni_vp->v_type != VREG)
1938 goto bad;
1939 best = cp = NULL;
1940 error = VOP_GETATTR(nd.ni_vp, &vattr, cred);
1941 if (error)
1942 goto bad;
1943 /*
1944 * XXX: we need to limit this number to some reasonable value
1945 */
1946 if (vattr.va_size > LINKER_HINTS_MAX) {
1947 printf("linker.hints file too large %ld\n", (long)vattr.va_size);
1948 goto bad;
1949 }
1950 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK);
1951 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0,
1952 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td);
1953 if (error)
1954 goto bad;
1955 VOP_UNLOCK(nd.ni_vp);
1956 vn_close(nd.ni_vp, FREAD, cred, td);
1957 nd.ni_vp = NULL;
1958 if (reclen != 0) {
1959 printf("can't read %zd\n", reclen);
1960 goto bad;
1961 }
1962 intp = (int *)hints;
1963 ival = *intp++;
1964 if (ival != LINKER_HINTS_VERSION) {
1965 printf("linker.hints file version mismatch %d\n", ival);
1966 goto bad;
1967 }
1968 bufend = hints + vattr.va_size;
1969 recptr = (u_char *)intp;
1970 clen = blen = 0;
1971 while (recptr < bufend && !found) {
1972 intp = (int *)recptr;
1973 reclen = *intp++;
1974 ival = *intp++;
1975 cp = (char *)intp;
1976 switch (ival) {
1977 case MDT_VERSION:
1978 clen = *cp++;
1979 if (clen != modnamelen || bcmp(cp, modname, clen) != 0)
1980 break;
1981 cp += clen;
1982 INT_ALIGN(hints, cp);
1983 ival = *(int *)cp;
1984 cp += sizeof(int);
1985 clen = *cp++;
1986 if (verinfo == NULL ||
1987 ival == verinfo->md_ver_preferred) {
1988 found = 1;
1989 break;
1990 }
1991 if (ival >= verinfo->md_ver_minimum &&
1992 ival <= verinfo->md_ver_maximum &&
1993 ival > bestver) {
1994 bestver = ival;
1995 best = cp;
1996 blen = clen;
1997 }
1998 break;
1999 default:
2000 break;
2001 }
2002 recptr += reclen + sizeof(int);
2003 }
2004 /*
2005 * Finally check if KLD is in the place
2006 */
2007 if (found)
2008 result = linker_lookup_file(path, pathlen, cp, clen, &mattr);
2009 else if (best)
2010 result = linker_lookup_file(path, pathlen, best, blen, &mattr);
2011
2012 /*
2013 * KLD is newer than hints file. What we should do now?
2014 */
2015 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >))
2016 printf("warning: KLD '%s' is newer than the linker.hints"
2017 " file\n", result);
2018 bad:
2019 free(pathbuf, M_LINKER);
2020 if (hints)
2021 free(hints, M_TEMP);
2022 if (nd.ni_vp != NULL) {
2023 VOP_UNLOCK(nd.ni_vp);
2024 vn_close(nd.ni_vp, FREAD, cred, td);
2025 }
2026 /*
2027 * If nothing found or hints is absent - fallback to the old
2028 * way by using "kldname[.ko]" as module name.
2029 */
2030 if (!found && !bestver && result == NULL)
2031 result = linker_lookup_file(path, pathlen, modname,
2032 modnamelen, NULL);
2033 return (result);
2034 }
2035
2036 /*
2037 * Lookup KLD which contains requested module in the all directories.
2038 */
2039 static char *
2040 linker_search_module(const char *modname, int modnamelen,
2041 const struct mod_depend *verinfo)
2042 {
2043 char *cp, *ep, *result;
2044
2045 /*
2046 * traverse the linker path
2047 */
2048 for (cp = linker_path; *cp; cp = ep + 1) {
2049 /* find the end of this component */
2050 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++);
2051 result = linker_hints_lookup(cp, ep - cp, modname,
2052 modnamelen, verinfo);
2053 if (result != NULL)
2054 return (result);
2055 if (*ep == 0)
2056 break;
2057 }
2058 return (NULL);
2059 }
2060
2061 /*
2062 * Search for module in all directories listed in the linker_path.
2063 */
2064 static char *
2065 linker_search_kld(const char *name)
2066 {
2067 char *cp, *ep, *result;
2068 int len;
2069
2070 /* qualified at all? */
2071 if (strchr(name, '/'))
2072 return (strdup(name, M_LINKER));
2073
2074 /* traverse the linker path */
2075 len = strlen(name);
2076 for (ep = linker_path; *ep; ep++) {
2077 cp = ep;
2078 /* find the end of this component */
2079 for (; *ep != 0 && *ep != ';'; ep++);
2080 result = linker_lookup_file(cp, ep - cp, name, len, NULL);
2081 if (result != NULL)
2082 return (result);
2083 }
2084 return (NULL);
2085 }
2086
2087 static const char *
2088 linker_basename(const char *path)
2089 {
2090 const char *filename;
2091
2092 filename = strrchr(path, '/');
2093 if (filename == NULL)
2094 return path;
2095 if (filename[1])
2096 filename++;
2097 return (filename);
2098 }
2099
2100 #ifdef HWPMC_HOOKS
2101 /*
2102 * Inform hwpmc about the set of kernel modules currently loaded.
2103 */
2104 void *
2105 linker_hwpmc_list_objects(void)
2106 {
2107 linker_file_t lf;
2108 struct pmckern_map_in *kobase;
2109 int i, nmappings;
2110
2111 nmappings = 0;
2112 sx_slock(&kld_sx);
2113 TAILQ_FOREACH(lf, &linker_files, link)
2114 nmappings++;
2115
2116 /* Allocate nmappings + 1 entries. */
2117 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in),
2118 M_LINKER, M_WAITOK | M_ZERO);
2119 i = 0;
2120 TAILQ_FOREACH(lf, &linker_files, link) {
2121 /* Save the info for this linker file. */
2122 kobase[i].pm_file = lf->filename;
2123 kobase[i].pm_address = (uintptr_t)lf->address;
2124 i++;
2125 }
2126 sx_sunlock(&kld_sx);
2127
2128 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?"));
2129
2130 /* The last entry of the malloced area comprises of all zeros. */
2131 KASSERT(kobase[i].pm_file == NULL,
2132 ("linker_hwpmc_list_objects: last object not NULL"));
2133
2134 return ((void *)kobase);
2135 }
2136 #endif
2137
2138 /* check if root file system is not mounted */
2139 static bool
2140 linker_root_mounted(void)
2141 {
2142 struct pwd *pwd;
2143 bool ret;
2144
2145 if (rootvnode == NULL)
2146 return (false);
2147
2148 pwd = pwd_hold(curthread);
2149 ret = pwd->pwd_rdir != NULL;
2150 pwd_drop(pwd);
2151 return (ret);
2152 }
2153
2154 /*
2155 * Find a file which contains given module and load it, if "parent" is not
2156 * NULL, register a reference to it.
2157 */
2158 static int
2159 linker_load_module(const char *kldname, const char *modname,
2160 struct linker_file *parent, const struct mod_depend *verinfo,
2161 struct linker_file **lfpp)
2162 {
2163 linker_file_t lfdep;
2164 const char *filename;
2165 char *pathname;
2166 int error;
2167
2168 sx_assert(&kld_sx, SA_XLOCKED);
2169 if (modname == NULL) {
2170 /*
2171 * We have to load KLD
2172 */
2173 KASSERT(verinfo == NULL, ("linker_load_module: verinfo"
2174 " is not NULL"));
2175 if (!linker_root_mounted())
2176 return (ENXIO);
2177 pathname = linker_search_kld(kldname);
2178 } else {
2179 if (modlist_lookup2(modname, verinfo) != NULL)
2180 return (EEXIST);
2181 if (!linker_root_mounted())
2182 return (ENXIO);
2183 if (kldname != NULL)
2184 pathname = strdup(kldname, M_LINKER);
2185 else
2186 /*
2187 * Need to find a KLD with required module
2188 */
2189 pathname = linker_search_module(modname,
2190 strlen(modname), verinfo);
2191 }
2192 if (pathname == NULL)
2193 return (ENOENT);
2194
2195 /*
2196 * Can't load more than one file with the same basename XXX:
2197 * Actually it should be possible to have multiple KLDs with
2198 * the same basename but different path because they can
2199 * provide different versions of the same modules.
2200 */
2201 filename = linker_basename(pathname);
2202 if (linker_find_file_by_name(filename))
2203 error = EEXIST;
2204 else do {
2205 error = linker_load_file(pathname, &lfdep);
2206 if (error)
2207 break;
2208 if (modname && verinfo &&
2209 modlist_lookup2(modname, verinfo) == NULL) {
2210 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE);
2211 error = ENOENT;
2212 break;
2213 }
2214 if (parent) {
2215 error = linker_file_add_dependency(parent, lfdep);
2216 if (error)
2217 break;
2218 }
2219 if (lfpp)
2220 *lfpp = lfdep;
2221 } while (0);
2222 free(pathname, M_LINKER);
2223 return (error);
2224 }
2225
2226 /*
2227 * This routine is responsible for finding dependencies of userland initiated
2228 * kldload(2)'s of files.
2229 */
2230 int
2231 linker_load_dependencies(linker_file_t lf)
2232 {
2233 linker_file_t lfdep;
2234 struct mod_metadata **start, **stop, **mdp, **nmdp;
2235 struct mod_metadata *mp, *nmp;
2236 const struct mod_depend *verinfo;
2237 modlist_t mod;
2238 const char *modname, *nmodname;
2239 int ver, error = 0;
2240
2241 /*
2242 * All files are dependent on /kernel.
2243 */
2244 sx_assert(&kld_sx, SA_XLOCKED);
2245 if (linker_kernel_file) {
2246 linker_kernel_file->refs++;
2247 error = linker_file_add_dependency(lf, linker_kernel_file);
2248 if (error)
2249 return (error);
2250 }
2251 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop,
2252 NULL) != 0)
2253 return (0);
2254 for (mdp = start; mdp < stop; mdp++) {
2255 mp = *mdp;
2256 if (mp->md_type != MDT_VERSION)
2257 continue;
2258 modname = mp->md_cval;
2259 ver = ((const struct mod_version *)mp->md_data)->mv_version;
2260 mod = modlist_lookup(modname, ver);
2261 if (mod != NULL) {
2262 printf("interface %s.%d already present in the KLD"
2263 " '%s'!\n", modname, ver,
2264 mod->container->filename);
2265 return (EEXIST);
2266 }
2267 }
2268
2269 for (mdp = start; mdp < stop; mdp++) {
2270 mp = *mdp;
2271 if (mp->md_type != MDT_DEPEND)
2272 continue;
2273 modname = mp->md_cval;
2274 verinfo = mp->md_data;
2275 nmodname = NULL;
2276 for (nmdp = start; nmdp < stop; nmdp++) {
2277 nmp = *nmdp;
2278 if (nmp->md_type != MDT_VERSION)
2279 continue;
2280 nmodname = nmp->md_cval;
2281 if (strcmp(modname, nmodname) == 0)
2282 break;
2283 }
2284 if (nmdp < stop)/* early exit, it's a self reference */
2285 continue;
2286 mod = modlist_lookup2(modname, verinfo);
2287 if (mod) { /* woohoo, it's loaded already */
2288 lfdep = mod->container;
2289 lfdep->refs++;
2290 error = linker_file_add_dependency(lf, lfdep);
2291 if (error)
2292 break;
2293 continue;
2294 }
2295 error = linker_load_module(NULL, modname, lf, verinfo, NULL);
2296 if (error) {
2297 printf("KLD %s: depends on %s - not available or"
2298 " version mismatch\n", lf->filename, modname);
2299 break;
2300 }
2301 }
2302
2303 if (error)
2304 return (error);
2305 linker_addmodules(lf, start, stop, 0);
2306 return (error);
2307 }
2308
2309 static int
2310 sysctl_kern_function_list_iterate(const char *name, void *opaque)
2311 {
2312 struct sysctl_req *req;
2313
2314 req = opaque;
2315 return (SYSCTL_OUT(req, name, strlen(name) + 1));
2316 }
2317
2318 /*
2319 * Export a nul-separated, double-nul-terminated list of all function names
2320 * in the kernel.
2321 */
2322 static int
2323 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS)
2324 {
2325 linker_file_t lf;
2326 int error;
2327
2328 #ifdef MAC
2329 error = mac_kld_check_stat(req->td->td_ucred);
2330 if (error)
2331 return (error);
2332 #endif
2333 error = sysctl_wire_old_buffer(req, 0);
2334 if (error != 0)
2335 return (error);
2336 sx_xlock(&kld_sx);
2337 TAILQ_FOREACH(lf, &linker_files, link) {
2338 error = LINKER_EACH_FUNCTION_NAME(lf,
2339 sysctl_kern_function_list_iterate, req);
2340 if (error) {
2341 sx_xunlock(&kld_sx);
2342 return (error);
2343 }
2344 }
2345 sx_xunlock(&kld_sx);
2346 return (SYSCTL_OUT(req, "", 1));
2347 }
2348
2349 SYSCTL_PROC(_kern, OID_AUTO, function_list,
2350 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
2351 sysctl_kern_function_list, "",
2352 "kernel function list");
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