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/kernel.h>
38 #include <sys/systm.h>
39 #include <sys/malloc.h>
40 #include <sys/sysproto.h>
41 #include <sys/sysent.h>
42 #include <sys/priv.h>
43 #include <sys/proc.h>
44 #include <sys/lock.h>
45 #include <sys/mutex.h>
46 #include <sys/sx.h>
47 #include <sys/module.h>
48 #include <sys/mount.h>
49 #include <sys/linker.h>
50 #include <sys/eventhandler.h>
51 #include <sys/fcntl.h>
52 #include <sys/jail.h>
53 #include <sys/libkern.h>
54 #include <sys/namei.h>
55 #include <sys/vnode.h>
56 #include <sys/syscallsubr.h>
57 #include <sys/sysctl.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
110 /*
111 * Load counter used by clients to determine if a linker file has been
112 * re-loaded. This counter is incremented for each file load.
113 */
114 static int loadcnt;
115
116 static linker_class_list_t classes;
117 static linker_file_list_t linker_files;
118 static int next_file_id = 1;
119 static int linker_no_more_classes = 0;
120
121 #define LINKER_GET_NEXT_FILE_ID(a) do { \
122 linker_file_t lftmp; \
123 \
124 if (!cold) \
125 sx_assert(&kld_sx, SA_XLOCKED); \
126 retry: \
127 TAILQ_FOREACH(lftmp, &linker_files, link) { \
128 if (next_file_id == lftmp->id) { \
129 next_file_id++; \
130 goto retry; \
131 } \
132 } \
133 (a) = next_file_id; \
134 } while(0)
135
136
137 /* XXX wrong name; we're looking at version provision tags here, not modules */
138 typedef TAILQ_HEAD(, modlist) modlisthead_t;
139 struct modlist {
140 TAILQ_ENTRY(modlist) link; /* chain together all modules */
141 linker_file_t container;
142 const char *name;
143 int version;
144 };
145 typedef struct modlist *modlist_t;
146 static modlisthead_t found_modules;
147
148 static int linker_file_add_dependency(linker_file_t file,
149 linker_file_t dep);
150 static caddr_t linker_file_lookup_symbol_internal(linker_file_t file,
151 const char* name, int deps);
152 static int linker_load_module(const char *kldname,
153 const char *modname, struct linker_file *parent,
154 const struct mod_depend *verinfo, struct linker_file **lfpp);
155 static modlist_t modlist_lookup2(const char *name, const struct mod_depend *verinfo);
156
157 static void
158 linker_init(void *arg)
159 {
160
161 sx_init(&kld_sx, "kernel linker");
162 TAILQ_INIT(&classes);
163 TAILQ_INIT(&linker_files);
164 }
165
166 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, NULL);
167
168 static void
169 linker_stop_class_add(void *arg)
170 {
171
172 linker_no_more_classes = 1;
173 }
174
175 SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL);
176
177 int
178 linker_add_class(linker_class_t lc)
179 {
180
181 /*
182 * We disallow any class registration past SI_ORDER_ANY
183 * of SI_SUB_KLD. We bump the reference count to keep the
184 * ops from being freed.
185 */
186 if (linker_no_more_classes == 1)
187 return (EPERM);
188 kobj_class_compile((kobj_class_t) lc);
189 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */
190 TAILQ_INSERT_TAIL(&classes, lc, link);
191 return (0);
192 }
193
194 static void
195 linker_file_sysinit(linker_file_t lf)
196 {
197 struct sysinit **start, **stop, **sipp, **xipp, *save;
198
199 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n",
200 lf->filename));
201
202 sx_assert(&kld_sx, SA_XLOCKED);
203
204 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0)
205 return;
206 /*
207 * Perform a bubble sort of the system initialization objects by
208 * their subsystem (primary key) and order (secondary key).
209 *
210 * Since some things care about execution order, this is the operation
211 * which ensures continued function.
212 */
213 for (sipp = start; sipp < stop; sipp++) {
214 for (xipp = sipp + 1; xipp < stop; xipp++) {
215 if ((*sipp)->subsystem < (*xipp)->subsystem ||
216 ((*sipp)->subsystem == (*xipp)->subsystem &&
217 (*sipp)->order <= (*xipp)->order))
218 continue; /* skip */
219 save = *sipp;
220 *sipp = *xipp;
221 *xipp = save;
222 }
223 }
224
225 /*
226 * Traverse the (now) ordered list of system initialization tasks.
227 * Perform each task, and continue on to the next task.
228 */
229 sx_xunlock(&kld_sx);
230 mtx_lock(&Giant);
231 for (sipp = start; sipp < stop; sipp++) {
232 if ((*sipp)->subsystem == SI_SUB_DUMMY)
233 continue; /* skip dummy task(s) */
234
235 /* Call function */
236 (*((*sipp)->func)) ((*sipp)->udata);
237 }
238 mtx_unlock(&Giant);
239 sx_xlock(&kld_sx);
240 }
241
242 static void
243 linker_file_sysuninit(linker_file_t lf)
244 {
245 struct sysinit **start, **stop, **sipp, **xipp, *save;
246
247 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n",
248 lf->filename));
249
250 sx_assert(&kld_sx, SA_XLOCKED);
251
252 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop,
253 NULL) != 0)
254 return;
255
256 /*
257 * Perform a reverse bubble sort of the system initialization objects
258 * by their subsystem (primary key) and order (secondary key).
259 *
260 * Since some things care about execution order, this is the operation
261 * which ensures continued function.
262 */
263 for (sipp = start; sipp < stop; sipp++) {
264 for (xipp = sipp + 1; xipp < stop; xipp++) {
265 if ((*sipp)->subsystem > (*xipp)->subsystem ||
266 ((*sipp)->subsystem == (*xipp)->subsystem &&
267 (*sipp)->order >= (*xipp)->order))
268 continue; /* skip */
269 save = *sipp;
270 *sipp = *xipp;
271 *xipp = save;
272 }
273 }
274
275 /*
276 * Traverse the (now) ordered list of system initialization tasks.
277 * Perform each task, and continue on to the next task.
278 */
279 sx_xunlock(&kld_sx);
280 mtx_lock(&Giant);
281 for (sipp = start; sipp < stop; sipp++) {
282 if ((*sipp)->subsystem == SI_SUB_DUMMY)
283 continue; /* skip dummy task(s) */
284
285 /* Call function */
286 (*((*sipp)->func)) ((*sipp)->udata);
287 }
288 mtx_unlock(&Giant);
289 sx_xlock(&kld_sx);
290 }
291
292 static void
293 linker_file_register_sysctls(linker_file_t lf, bool enable)
294 {
295 struct sysctl_oid **start, **stop, **oidp;
296
297 KLD_DPF(FILE,
298 ("linker_file_register_sysctls: registering SYSCTLs for %s\n",
299 lf->filename));
300
301 sx_assert(&kld_sx, SA_XLOCKED);
302
303 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
304 return;
305
306 sx_xunlock(&kld_sx);
307 sysctl_wlock();
308 for (oidp = start; oidp < stop; oidp++) {
309 if (enable)
310 sysctl_register_oid(*oidp);
311 else
312 sysctl_register_disabled_oid(*oidp);
313 }
314 sysctl_wunlock();
315 sx_xlock(&kld_sx);
316 }
317
318 static void
319 linker_file_enable_sysctls(linker_file_t lf)
320 {
321 struct sysctl_oid **start, **stop, **oidp;
322
323 KLD_DPF(FILE,
324 ("linker_file_enable_sysctls: enable SYSCTLs for %s\n",
325 lf->filename));
326
327 sx_assert(&kld_sx, SA_XLOCKED);
328
329 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
330 return;
331
332 sx_xunlock(&kld_sx);
333 sysctl_wlock();
334 for (oidp = start; oidp < stop; oidp++)
335 sysctl_enable_oid(*oidp);
336 sysctl_wunlock();
337 sx_xlock(&kld_sx);
338 }
339
340 static void
341 linker_file_unregister_sysctls(linker_file_t lf)
342 {
343 struct sysctl_oid **start, **stop, **oidp;
344
345 KLD_DPF(FILE, ("linker_file_unregister_sysctls: unregistering SYSCTLs"
346 " for %s\n", lf->filename));
347
348 sx_assert(&kld_sx, SA_XLOCKED);
349
350 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
351 return;
352
353 sx_xunlock(&kld_sx);
354 sysctl_wlock();
355 for (oidp = start; oidp < stop; oidp++)
356 sysctl_unregister_oid(*oidp);
357 sysctl_wunlock();
358 sx_xlock(&kld_sx);
359 }
360
361 static int
362 linker_file_register_modules(linker_file_t lf)
363 {
364 struct mod_metadata **start, **stop, **mdp;
365 const moduledata_t *moddata;
366 int first_error, error;
367
368 KLD_DPF(FILE, ("linker_file_register_modules: registering modules"
369 " in %s\n", lf->filename));
370
371 sx_assert(&kld_sx, SA_XLOCKED);
372
373 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL) != 0) {
374 /*
375 * This fallback should be unnecessary, but if we get booted
376 * from boot2 instead of loader and we are missing our
377 * metadata then we have to try the best we can.
378 */
379 if (lf == linker_kernel_file) {
380 start = SET_BEGIN(modmetadata_set);
381 stop = SET_LIMIT(modmetadata_set);
382 } else
383 return (0);
384 }
385 first_error = 0;
386 for (mdp = start; mdp < stop; mdp++) {
387 if ((*mdp)->md_type != MDT_MODULE)
388 continue;
389 moddata = (*mdp)->md_data;
390 KLD_DPF(FILE, ("Registering module %s in %s\n",
391 moddata->name, lf->filename));
392 error = module_register(moddata, lf);
393 if (error) {
394 printf("Module %s failed to register: %d\n",
395 moddata->name, error);
396 if (first_error == 0)
397 first_error = error;
398 }
399 }
400 return (first_error);
401 }
402
403 static void
404 linker_init_kernel_modules(void)
405 {
406
407 sx_xlock(&kld_sx);
408 linker_file_register_modules(linker_kernel_file);
409 sx_xunlock(&kld_sx);
410 }
411
412 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules,
413 NULL);
414
415 static int
416 linker_load_file(const char *filename, linker_file_t *result)
417 {
418 linker_class_t lc;
419 linker_file_t lf;
420 int foundfile, error, modules;
421
422 /* Refuse to load modules if securelevel raised */
423 if (prison0.pr_securelevel > 0)
424 return (EPERM);
425
426 sx_assert(&kld_sx, SA_XLOCKED);
427 lf = linker_find_file_by_name(filename);
428 if (lf) {
429 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded,"
430 " incrementing refs\n", filename));
431 *result = lf;
432 lf->refs++;
433 return (0);
434 }
435 foundfile = 0;
436 error = 0;
437
438 /*
439 * We do not need to protect (lock) classes here because there is
440 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY)
441 * and there is no class deregistration mechanism at this time.
442 */
443 TAILQ_FOREACH(lc, &classes, link) {
444 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n",
445 filename));
446 error = LINKER_LOAD_FILE(lc, filename, &lf);
447 /*
448 * If we got something other than ENOENT, then it exists but
449 * we cannot load it for some other reason.
450 */
451 if (error != ENOENT)
452 foundfile = 1;
453 if (lf) {
454 error = linker_file_register_modules(lf);
455 if (error == EEXIST) {
456 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
457 return (error);
458 }
459 modules = !TAILQ_EMPTY(&lf->modules);
460 linker_file_register_sysctls(lf, false);
461 linker_file_sysinit(lf);
462 lf->flags |= LINKER_FILE_LINKED;
463
464 /*
465 * If all of the modules in this file failed
466 * to load, unload the file and return an
467 * error of ENOEXEC.
468 */
469 if (modules && TAILQ_EMPTY(&lf->modules)) {
470 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
471 return (ENOEXEC);
472 }
473 linker_file_enable_sysctls(lf);
474 EVENTHANDLER_INVOKE(kld_load, lf);
475 *result = lf;
476 return (0);
477 }
478 }
479 /*
480 * Less than ideal, but tells the user whether it failed to load or
481 * the module was not found.
482 */
483 if (foundfile) {
484
485 /*
486 * If the file type has not been recognized by the last try
487 * printout a message before to fail.
488 */
489 if (error == ENOSYS)
490 printf("%s: %s - unsupported file type\n",
491 __func__, filename);
492
493 /*
494 * Format not recognized or otherwise unloadable.
495 * When loading a module that is statically built into
496 * the kernel EEXIST percolates back up as the return
497 * value. Preserve this so that apps like sysinstall
498 * can recognize this special case and not post bogus
499 * dialog boxes.
500 */
501 if (error != EEXIST)
502 error = ENOEXEC;
503 } else
504 error = ENOENT; /* Nothing found */
505 return (error);
506 }
507
508 int
509 linker_reference_module(const char *modname, struct mod_depend *verinfo,
510 linker_file_t *result)
511 {
512 modlist_t mod;
513 int error;
514
515 sx_xlock(&kld_sx);
516 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) {
517 *result = mod->container;
518 (*result)->refs++;
519 sx_xunlock(&kld_sx);
520 return (0);
521 }
522
523 error = linker_load_module(NULL, modname, NULL, verinfo, result);
524 sx_xunlock(&kld_sx);
525 return (error);
526 }
527
528 int
529 linker_release_module(const char *modname, struct mod_depend *verinfo,
530 linker_file_t lf)
531 {
532 modlist_t mod;
533 int error;
534
535 sx_xlock(&kld_sx);
536 if (lf == NULL) {
537 KASSERT(modname != NULL,
538 ("linker_release_module: no file or name"));
539 mod = modlist_lookup2(modname, verinfo);
540 if (mod == NULL) {
541 sx_xunlock(&kld_sx);
542 return (ESRCH);
543 }
544 lf = mod->container;
545 } else
546 KASSERT(modname == NULL && verinfo == NULL,
547 ("linker_release_module: both file and name"));
548 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL);
549 sx_xunlock(&kld_sx);
550 return (error);
551 }
552
553 static linker_file_t
554 linker_find_file_by_name(const char *filename)
555 {
556 linker_file_t lf;
557 char *koname;
558
559 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK);
560 sprintf(koname, "%s.ko", filename);
561
562 sx_assert(&kld_sx, SA_XLOCKED);
563 TAILQ_FOREACH(lf, &linker_files, link) {
564 if (strcmp(lf->filename, koname) == 0)
565 break;
566 if (strcmp(lf->filename, filename) == 0)
567 break;
568 }
569 free(koname, M_LINKER);
570 return (lf);
571 }
572
573 static linker_file_t
574 linker_find_file_by_id(int fileid)
575 {
576 linker_file_t lf;
577
578 sx_assert(&kld_sx, SA_XLOCKED);
579 TAILQ_FOREACH(lf, &linker_files, link)
580 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED)
581 break;
582 return (lf);
583 }
584
585 int
586 linker_file_foreach(linker_predicate_t *predicate, void *context)
587 {
588 linker_file_t lf;
589 int retval = 0;
590
591 sx_xlock(&kld_sx);
592 TAILQ_FOREACH(lf, &linker_files, link) {
593 retval = predicate(lf, context);
594 if (retval != 0)
595 break;
596 }
597 sx_xunlock(&kld_sx);
598 return (retval);
599 }
600
601 linker_file_t
602 linker_make_file(const char *pathname, linker_class_t lc)
603 {
604 linker_file_t lf;
605 const char *filename;
606
607 if (!cold)
608 sx_assert(&kld_sx, SA_XLOCKED);
609 filename = linker_basename(pathname);
610
611 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname));
612 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK);
613 if (lf == NULL)
614 return (NULL);
615 lf->ctors_addr = 0;
616 lf->ctors_size = 0;
617 lf->refs = 1;
618 lf->userrefs = 0;
619 lf->flags = 0;
620 lf->filename = strdup(filename, M_LINKER);
621 lf->pathname = strdup(pathname, M_LINKER);
622 LINKER_GET_NEXT_FILE_ID(lf->id);
623 lf->ndeps = 0;
624 lf->deps = NULL;
625 lf->loadcnt = ++loadcnt;
626 #ifdef __arm__
627 lf->exidx_addr = 0;
628 lf->exidx_size = 0;
629 #endif
630 STAILQ_INIT(&lf->common);
631 TAILQ_INIT(&lf->modules);
632 TAILQ_INSERT_TAIL(&linker_files, lf, link);
633 return (lf);
634 }
635
636 int
637 linker_file_unload(linker_file_t file, int flags)
638 {
639 module_t mod, next;
640 modlist_t ml, nextml;
641 struct common_symbol *cp;
642 int error, i;
643
644 /* Refuse to unload modules if securelevel raised. */
645 if (prison0.pr_securelevel > 0)
646 return (EPERM);
647
648 sx_assert(&kld_sx, SA_XLOCKED);
649 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs));
650
651 /* Easy case of just dropping a reference. */
652 if (file->refs > 1) {
653 file->refs--;
654 return (0);
655 }
656
657 /* Give eventhandlers a chance to prevent the unload. */
658 error = 0;
659 EVENTHANDLER_INVOKE(kld_unload_try, file, &error);
660 if (error != 0)
661 return (EBUSY);
662
663 KLD_DPF(FILE, ("linker_file_unload: file is unloading,"
664 " informing modules\n"));
665
666 /*
667 * Quiesce all the modules to give them a chance to veto the unload.
668 */
669 MOD_SLOCK;
670 for (mod = TAILQ_FIRST(&file->modules); mod;
671 mod = module_getfnext(mod)) {
672
673 error = module_quiesce(mod);
674 if (error != 0 && flags != LINKER_UNLOAD_FORCE) {
675 KLD_DPF(FILE, ("linker_file_unload: module %s"
676 " vetoed unload\n", module_getname(mod)));
677 /*
678 * XXX: Do we need to tell all the quiesced modules
679 * that they can resume work now via a new module
680 * event?
681 */
682 MOD_SUNLOCK;
683 return (error);
684 }
685 }
686 MOD_SUNLOCK;
687
688 /*
689 * Inform any modules associated with this file that they are
690 * being unloaded.
691 */
692 MOD_XLOCK;
693 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) {
694 next = module_getfnext(mod);
695 MOD_XUNLOCK;
696
697 /*
698 * Give the module a chance to veto the unload.
699 */
700 if ((error = module_unload(mod)) != 0) {
701 #ifdef KLD_DEBUG
702 MOD_SLOCK;
703 KLD_DPF(FILE, ("linker_file_unload: module %s"
704 " failed unload\n", module_getname(mod)));
705 MOD_SUNLOCK;
706 #endif
707 return (error);
708 }
709 MOD_XLOCK;
710 module_release(mod);
711 }
712 MOD_XUNLOCK;
713
714 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) {
715 if (ml->container == file) {
716 TAILQ_REMOVE(&found_modules, ml, link);
717 free(ml, M_LINKER);
718 }
719 }
720
721 /*
722 * Don't try to run SYSUNINITs if we are unloaded due to a
723 * link error.
724 */
725 if (file->flags & LINKER_FILE_LINKED) {
726 file->flags &= ~LINKER_FILE_LINKED;
727 linker_file_unregister_sysctls(file);
728 linker_file_sysuninit(file);
729 }
730 TAILQ_REMOVE(&linker_files, file, link);
731
732 if (file->deps) {
733 for (i = 0; i < file->ndeps; i++)
734 linker_file_unload(file->deps[i], flags);
735 free(file->deps, M_LINKER);
736 file->deps = NULL;
737 }
738 while ((cp = STAILQ_FIRST(&file->common)) != NULL) {
739 STAILQ_REMOVE_HEAD(&file->common, link);
740 free(cp, M_LINKER);
741 }
742
743 LINKER_UNLOAD(file);
744
745 EVENTHANDLER_INVOKE(kld_unload, file->filename, file->address,
746 file->size);
747
748 if (file->filename) {
749 free(file->filename, M_LINKER);
750 file->filename = NULL;
751 }
752 if (file->pathname) {
753 free(file->pathname, M_LINKER);
754 file->pathname = NULL;
755 }
756 kobj_delete((kobj_t) file, M_LINKER);
757 return (0);
758 }
759
760 int
761 linker_ctf_get(linker_file_t file, linker_ctf_t *lc)
762 {
763 return (LINKER_CTF_GET(file, lc));
764 }
765
766 static int
767 linker_file_add_dependency(linker_file_t file, linker_file_t dep)
768 {
769 linker_file_t *newdeps;
770
771 sx_assert(&kld_sx, SA_XLOCKED);
772 file->deps = realloc(file->deps, (file->ndeps + 1) * sizeof(*newdeps),
773 M_LINKER, M_WAITOK | M_ZERO);
774 file->deps[file->ndeps] = dep;
775 file->ndeps++;
776 KLD_DPF(FILE, ("linker_file_add_dependency:"
777 " adding %s as dependency for %s\n",
778 dep->filename, file->filename));
779 return (0);
780 }
781
782 /*
783 * Locate a linker set and its contents. This is a helper function to avoid
784 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **.
785 * This function is used in this file so we can avoid having lots of (void **)
786 * casts.
787 */
788 int
789 linker_file_lookup_set(linker_file_t file, const char *name,
790 void *firstp, void *lastp, int *countp)
791 {
792
793 sx_assert(&kld_sx, SA_LOCKED);
794 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp));
795 }
796
797 /*
798 * List all functions in a file.
799 */
800 int
801 linker_file_function_listall(linker_file_t lf,
802 linker_function_nameval_callback_t callback_func, void *arg)
803 {
804 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg));
805 }
806
807 caddr_t
808 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps)
809 {
810 caddr_t sym;
811 int locked;
812
813 locked = sx_xlocked(&kld_sx);
814 if (!locked)
815 sx_xlock(&kld_sx);
816 sym = linker_file_lookup_symbol_internal(file, name, deps);
817 if (!locked)
818 sx_xunlock(&kld_sx);
819 return (sym);
820 }
821
822 static caddr_t
823 linker_file_lookup_symbol_internal(linker_file_t file, const char *name,
824 int deps)
825 {
826 c_linker_sym_t sym;
827 linker_symval_t symval;
828 caddr_t address;
829 size_t common_size = 0;
830 int i;
831
832 sx_assert(&kld_sx, SA_XLOCKED);
833 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n",
834 file, name, deps));
835
836 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) {
837 LINKER_SYMBOL_VALUES(file, sym, &symval);
838 if (symval.value == 0)
839 /*
840 * For commons, first look them up in the
841 * dependencies and only allocate space if not found
842 * there.
843 */
844 common_size = symval.size;
845 else {
846 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol"
847 ".value=%p\n", symval.value));
848 return (symval.value);
849 }
850 }
851 if (deps) {
852 for (i = 0; i < file->ndeps; i++) {
853 address = linker_file_lookup_symbol_internal(
854 file->deps[i], name, 0);
855 if (address) {
856 KLD_DPF(SYM, ("linker_file_lookup_symbol:"
857 " deps value=%p\n", address));
858 return (address);
859 }
860 }
861 }
862 if (common_size > 0) {
863 /*
864 * This is a common symbol which was not found in the
865 * dependencies. We maintain a simple common symbol table in
866 * the file object.
867 */
868 struct common_symbol *cp;
869
870 STAILQ_FOREACH(cp, &file->common, link) {
871 if (strcmp(cp->name, name) == 0) {
872 KLD_DPF(SYM, ("linker_file_lookup_symbol:"
873 " old common value=%p\n", cp->address));
874 return (cp->address);
875 }
876 }
877 /*
878 * Round the symbol size up to align.
879 */
880 common_size = (common_size + sizeof(int) - 1) & -sizeof(int);
881 cp = malloc(sizeof(struct common_symbol)
882 + common_size + strlen(name) + 1, M_LINKER,
883 M_WAITOK | M_ZERO);
884 cp->address = (caddr_t)(cp + 1);
885 cp->name = cp->address + common_size;
886 strcpy(cp->name, name);
887 bzero(cp->address, common_size);
888 STAILQ_INSERT_TAIL(&file->common, cp, link);
889
890 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common"
891 " value=%p\n", cp->address));
892 return (cp->address);
893 }
894 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n"));
895 return (0);
896 }
897
898 /*
899 * Both DDB and stack(9) rely on the kernel linker to provide forward and
900 * backward lookup of symbols. However, DDB and sometimes stack(9) need to
901 * do this in a lockfree manner. We provide a set of internal helper
902 * routines to perform these operations without locks, and then wrappers that
903 * optionally lock.
904 *
905 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB.
906 */
907 #ifdef DDB
908 static int
909 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym)
910 {
911 linker_file_t lf;
912
913 TAILQ_FOREACH(lf, &linker_files, link) {
914 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0)
915 return (0);
916 }
917 return (ENOENT);
918 }
919 #endif
920
921 static int
922 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
923 {
924 linker_file_t lf;
925 c_linker_sym_t best, es;
926 u_long diff, bestdiff, off;
927
928 best = 0;
929 off = (uintptr_t)value;
930 bestdiff = off;
931 TAILQ_FOREACH(lf, &linker_files, link) {
932 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0)
933 continue;
934 if (es != 0 && diff < bestdiff) {
935 best = es;
936 bestdiff = diff;
937 }
938 if (bestdiff == 0)
939 break;
940 }
941 if (best) {
942 *sym = best;
943 *diffp = bestdiff;
944 return (0);
945 } else {
946 *sym = 0;
947 *diffp = off;
948 return (ENOENT);
949 }
950 }
951
952 static int
953 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
954 {
955 linker_file_t lf;
956
957 TAILQ_FOREACH(lf, &linker_files, link) {
958 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0)
959 return (0);
960 }
961 return (ENOENT);
962 }
963
964 static int
965 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen,
966 long *offset)
967 {
968 linker_symval_t symval;
969 c_linker_sym_t sym;
970 int error;
971
972 *offset = 0;
973 error = linker_debug_search_symbol(value, &sym, offset);
974 if (error)
975 return (error);
976 error = linker_debug_symbol_values(sym, &symval);
977 if (error)
978 return (error);
979 strlcpy(buf, symval.name, buflen);
980 return (0);
981 }
982
983 /*
984 * DDB Helpers. DDB has to look across multiple files with their own symbol
985 * tables and string tables.
986 *
987 * Note that we do not obey list locking protocols here. We really don't need
988 * DDB to hang because somebody's got the lock held. We'll take the chance
989 * that the files list is inconsistent instead.
990 */
991 #ifdef DDB
992 int
993 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym)
994 {
995
996 return (linker_debug_lookup(symstr, sym));
997 }
998 #endif
999
1000 int
1001 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
1002 {
1003
1004 return (linker_debug_search_symbol(value, sym, diffp));
1005 }
1006
1007 int
1008 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
1009 {
1010
1011 return (linker_debug_symbol_values(sym, symval));
1012 }
1013
1014 int
1015 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen,
1016 long *offset)
1017 {
1018
1019 return (linker_debug_search_symbol_name(value, buf, buflen, offset));
1020 }
1021
1022 /*
1023 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do
1024 * obey locking protocols, and offer a significantly less complex interface.
1025 */
1026 int
1027 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen,
1028 long *offset)
1029 {
1030 int error;
1031
1032 sx_slock(&kld_sx);
1033 error = linker_debug_search_symbol_name(value, buf, buflen, offset);
1034 sx_sunlock(&kld_sx);
1035 return (error);
1036 }
1037
1038 /*
1039 * Syscalls.
1040 */
1041 int
1042 kern_kldload(struct thread *td, const char *file, int *fileid)
1043 {
1044 const char *kldname, *modname;
1045 linker_file_t lf;
1046 int error;
1047
1048 if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
1049 return (error);
1050
1051 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0)
1052 return (error);
1053
1054 /*
1055 * It is possible that kldloaded module will attach a new ifnet,
1056 * so vnet context must be set when this ocurs.
1057 */
1058 CURVNET_SET(TD_TO_VNET(td));
1059
1060 /*
1061 * If file does not contain a qualified name or any dot in it
1062 * (kldname.ko, or kldname.ver.ko) treat it as an interface
1063 * name.
1064 */
1065 if (strchr(file, '/') || strchr(file, '.')) {
1066 kldname = file;
1067 modname = NULL;
1068 } else {
1069 kldname = NULL;
1070 modname = file;
1071 }
1072
1073 sx_xlock(&kld_sx);
1074 error = linker_load_module(kldname, modname, NULL, NULL, &lf);
1075 if (error) {
1076 sx_xunlock(&kld_sx);
1077 goto done;
1078 }
1079 lf->userrefs++;
1080 if (fileid != NULL)
1081 *fileid = lf->id;
1082 sx_xunlock(&kld_sx);
1083
1084 done:
1085 CURVNET_RESTORE();
1086 return (error);
1087 }
1088
1089 int
1090 sys_kldload(struct thread *td, struct kldload_args *uap)
1091 {
1092 char *pathname = NULL;
1093 int error, fileid;
1094
1095 td->td_retval[0] = -1;
1096
1097 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1098 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL);
1099 if (error == 0) {
1100 error = kern_kldload(td, pathname, &fileid);
1101 if (error == 0)
1102 td->td_retval[0] = fileid;
1103 }
1104 free(pathname, M_TEMP);
1105 return (error);
1106 }
1107
1108 int
1109 kern_kldunload(struct thread *td, int fileid, int flags)
1110 {
1111 linker_file_t lf;
1112 int error = 0;
1113
1114 if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
1115 return (error);
1116
1117 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0)
1118 return (error);
1119
1120 CURVNET_SET(TD_TO_VNET(td));
1121 sx_xlock(&kld_sx);
1122 lf = linker_find_file_by_id(fileid);
1123 if (lf) {
1124 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs));
1125
1126 if (lf->userrefs == 0) {
1127 /*
1128 * XXX: maybe LINKER_UNLOAD_FORCE should override ?
1129 */
1130 printf("kldunload: attempt to unload file that was"
1131 " loaded by the kernel\n");
1132 error = EBUSY;
1133 } else {
1134 lf->userrefs--;
1135 error = linker_file_unload(lf, flags);
1136 if (error)
1137 lf->userrefs++;
1138 }
1139 } else
1140 error = ENOENT;
1141 sx_xunlock(&kld_sx);
1142
1143 CURVNET_RESTORE();
1144 return (error);
1145 }
1146
1147 int
1148 sys_kldunload(struct thread *td, struct kldunload_args *uap)
1149 {
1150
1151 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL));
1152 }
1153
1154 int
1155 sys_kldunloadf(struct thread *td, struct kldunloadf_args *uap)
1156 {
1157
1158 if (uap->flags != LINKER_UNLOAD_NORMAL &&
1159 uap->flags != LINKER_UNLOAD_FORCE)
1160 return (EINVAL);
1161 return (kern_kldunload(td, uap->fileid, uap->flags));
1162 }
1163
1164 int
1165 sys_kldfind(struct thread *td, struct kldfind_args *uap)
1166 {
1167 char *pathname;
1168 const char *filename;
1169 linker_file_t lf;
1170 int error;
1171
1172 #ifdef MAC
1173 error = mac_kld_check_stat(td->td_ucred);
1174 if (error)
1175 return (error);
1176 #endif
1177
1178 td->td_retval[0] = -1;
1179
1180 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1181 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0)
1182 goto out;
1183
1184 filename = linker_basename(pathname);
1185 sx_xlock(&kld_sx);
1186 lf = linker_find_file_by_name(filename);
1187 if (lf)
1188 td->td_retval[0] = lf->id;
1189 else
1190 error = ENOENT;
1191 sx_xunlock(&kld_sx);
1192 out:
1193 free(pathname, M_TEMP);
1194 return (error);
1195 }
1196
1197 int
1198 sys_kldnext(struct thread *td, struct kldnext_args *uap)
1199 {
1200 linker_file_t lf;
1201 int error = 0;
1202
1203 #ifdef MAC
1204 error = mac_kld_check_stat(td->td_ucred);
1205 if (error)
1206 return (error);
1207 #endif
1208
1209 sx_xlock(&kld_sx);
1210 if (uap->fileid == 0)
1211 lf = TAILQ_FIRST(&linker_files);
1212 else {
1213 lf = linker_find_file_by_id(uap->fileid);
1214 if (lf == NULL) {
1215 error = ENOENT;
1216 goto out;
1217 }
1218 lf = TAILQ_NEXT(lf, link);
1219 }
1220
1221 /* Skip partially loaded files. */
1222 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED))
1223 lf = TAILQ_NEXT(lf, link);
1224
1225 if (lf)
1226 td->td_retval[0] = lf->id;
1227 else
1228 td->td_retval[0] = 0;
1229 out:
1230 sx_xunlock(&kld_sx);
1231 return (error);
1232 }
1233
1234 int
1235 sys_kldstat(struct thread *td, struct kldstat_args *uap)
1236 {
1237 struct kld_file_stat *stat;
1238 int error, version;
1239
1240 /*
1241 * Check the version of the user's structure.
1242 */
1243 if ((error = copyin(&uap->stat->version, &version, sizeof(version)))
1244 != 0)
1245 return (error);
1246 if (version != sizeof(struct kld_file_stat_1) &&
1247 version != sizeof(struct kld_file_stat))
1248 return (EINVAL);
1249
1250 stat = malloc(sizeof(*stat), M_TEMP, M_WAITOK | M_ZERO);
1251 error = kern_kldstat(td, uap->fileid, stat);
1252 if (error == 0)
1253 error = copyout(stat, uap->stat, version);
1254 free(stat, M_TEMP);
1255 return (error);
1256 }
1257
1258 int
1259 kern_kldstat(struct thread *td, int fileid, struct kld_file_stat *stat)
1260 {
1261 linker_file_t lf;
1262 int namelen;
1263 #ifdef MAC
1264 int error;
1265
1266 error = mac_kld_check_stat(td->td_ucred);
1267 if (error)
1268 return (error);
1269 #endif
1270
1271 sx_xlock(&kld_sx);
1272 lf = linker_find_file_by_id(fileid);
1273 if (lf == NULL) {
1274 sx_xunlock(&kld_sx);
1275 return (ENOENT);
1276 }
1277
1278 /* Version 1 fields: */
1279 namelen = strlen(lf->filename) + 1;
1280 if (namelen > sizeof(stat->name))
1281 namelen = sizeof(stat->name);
1282 bcopy(lf->filename, &stat->name[0], namelen);
1283 stat->refs = lf->refs;
1284 stat->id = lf->id;
1285 stat->address = lf->address;
1286 stat->size = lf->size;
1287 /* Version 2 fields: */
1288 namelen = strlen(lf->pathname) + 1;
1289 if (namelen > sizeof(stat->pathname))
1290 namelen = sizeof(stat->pathname);
1291 bcopy(lf->pathname, &stat->pathname[0], namelen);
1292 sx_xunlock(&kld_sx);
1293
1294 td->td_retval[0] = 0;
1295 return (0);
1296 }
1297
1298 #ifdef DDB
1299 DB_COMMAND(kldstat, db_kldstat)
1300 {
1301 linker_file_t lf;
1302
1303 #define POINTER_WIDTH ((int)(sizeof(void *) * 2 + 2))
1304 db_printf("Id Refs Address%*c Size Name\n", POINTER_WIDTH - 7, ' ');
1305 #undef POINTER_WIDTH
1306 TAILQ_FOREACH(lf, &linker_files, link) {
1307 if (db_pager_quit)
1308 return;
1309 db_printf("%2d %4d %p %-8zx %s\n", lf->id, lf->refs,
1310 lf->address, lf->size, lf->filename);
1311 }
1312 }
1313 #endif /* DDB */
1314
1315 int
1316 sys_kldfirstmod(struct thread *td, struct kldfirstmod_args *uap)
1317 {
1318 linker_file_t lf;
1319 module_t mp;
1320 int error = 0;
1321
1322 #ifdef MAC
1323 error = mac_kld_check_stat(td->td_ucred);
1324 if (error)
1325 return (error);
1326 #endif
1327
1328 sx_xlock(&kld_sx);
1329 lf = linker_find_file_by_id(uap->fileid);
1330 if (lf) {
1331 MOD_SLOCK;
1332 mp = TAILQ_FIRST(&lf->modules);
1333 if (mp != NULL)
1334 td->td_retval[0] = module_getid(mp);
1335 else
1336 td->td_retval[0] = 0;
1337 MOD_SUNLOCK;
1338 } else
1339 error = ENOENT;
1340 sx_xunlock(&kld_sx);
1341 return (error);
1342 }
1343
1344 int
1345 sys_kldsym(struct thread *td, struct kldsym_args *uap)
1346 {
1347 char *symstr = NULL;
1348 c_linker_sym_t sym;
1349 linker_symval_t symval;
1350 linker_file_t lf;
1351 struct kld_sym_lookup lookup;
1352 int error = 0;
1353
1354 #ifdef MAC
1355 error = mac_kld_check_stat(td->td_ucred);
1356 if (error)
1357 return (error);
1358 #endif
1359
1360 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0)
1361 return (error);
1362 if (lookup.version != sizeof(lookup) ||
1363 uap->cmd != KLDSYM_LOOKUP)
1364 return (EINVAL);
1365 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1366 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0)
1367 goto out;
1368 sx_xlock(&kld_sx);
1369 if (uap->fileid != 0) {
1370 lf = linker_find_file_by_id(uap->fileid);
1371 if (lf == NULL)
1372 error = ENOENT;
1373 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
1374 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
1375 lookup.symvalue = (uintptr_t) symval.value;
1376 lookup.symsize = symval.size;
1377 error = copyout(&lookup, uap->data, sizeof(lookup));
1378 } else
1379 error = ENOENT;
1380 } else {
1381 TAILQ_FOREACH(lf, &linker_files, link) {
1382 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
1383 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
1384 lookup.symvalue = (uintptr_t)symval.value;
1385 lookup.symsize = symval.size;
1386 error = copyout(&lookup, uap->data,
1387 sizeof(lookup));
1388 break;
1389 }
1390 }
1391 if (lf == NULL)
1392 error = ENOENT;
1393 }
1394 sx_xunlock(&kld_sx);
1395 out:
1396 free(symstr, M_TEMP);
1397 return (error);
1398 }
1399
1400 /*
1401 * Preloaded module support
1402 */
1403
1404 static modlist_t
1405 modlist_lookup(const char *name, int ver)
1406 {
1407 modlist_t mod;
1408
1409 TAILQ_FOREACH(mod, &found_modules, link) {
1410 if (strcmp(mod->name, name) == 0 &&
1411 (ver == 0 || mod->version == ver))
1412 return (mod);
1413 }
1414 return (NULL);
1415 }
1416
1417 static modlist_t
1418 modlist_lookup2(const char *name, const struct mod_depend *verinfo)
1419 {
1420 modlist_t mod, bestmod;
1421 int ver;
1422
1423 if (verinfo == NULL)
1424 return (modlist_lookup(name, 0));
1425 bestmod = NULL;
1426 TAILQ_FOREACH(mod, &found_modules, link) {
1427 if (strcmp(mod->name, name) != 0)
1428 continue;
1429 ver = mod->version;
1430 if (ver == verinfo->md_ver_preferred)
1431 return (mod);
1432 if (ver >= verinfo->md_ver_minimum &&
1433 ver <= verinfo->md_ver_maximum &&
1434 (bestmod == NULL || ver > bestmod->version))
1435 bestmod = mod;
1436 }
1437 return (bestmod);
1438 }
1439
1440 static modlist_t
1441 modlist_newmodule(const char *modname, int version, linker_file_t container)
1442 {
1443 modlist_t mod;
1444
1445 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO);
1446 if (mod == NULL)
1447 panic("no memory for module list");
1448 mod->container = container;
1449 mod->name = modname;
1450 mod->version = version;
1451 TAILQ_INSERT_TAIL(&found_modules, mod, link);
1452 return (mod);
1453 }
1454
1455 static void
1456 linker_addmodules(linker_file_t lf, struct mod_metadata **start,
1457 struct mod_metadata **stop, int preload)
1458 {
1459 struct mod_metadata *mp, **mdp;
1460 const char *modname;
1461 int ver;
1462
1463 for (mdp = start; mdp < stop; mdp++) {
1464 mp = *mdp;
1465 if (mp->md_type != MDT_VERSION)
1466 continue;
1467 modname = mp->md_cval;
1468 ver = ((const struct mod_version *)mp->md_data)->mv_version;
1469 if (modlist_lookup(modname, ver) != NULL) {
1470 printf("module %s already present!\n", modname);
1471 /* XXX what can we do? this is a build error. :-( */
1472 continue;
1473 }
1474 modlist_newmodule(modname, ver, lf);
1475 }
1476 }
1477
1478 static void
1479 linker_preload(void *arg)
1480 {
1481 caddr_t modptr;
1482 const char *modname, *nmodname;
1483 char *modtype;
1484 linker_file_t lf, nlf;
1485 linker_class_t lc;
1486 int error;
1487 linker_file_list_t loaded_files;
1488 linker_file_list_t depended_files;
1489 struct mod_metadata *mp, *nmp;
1490 struct mod_metadata **start, **stop, **mdp, **nmdp;
1491 const struct mod_depend *verinfo;
1492 int nver;
1493 int resolves;
1494 modlist_t mod;
1495 struct sysinit **si_start, **si_stop;
1496
1497 TAILQ_INIT(&loaded_files);
1498 TAILQ_INIT(&depended_files);
1499 TAILQ_INIT(&found_modules);
1500 error = 0;
1501
1502 modptr = NULL;
1503 sx_xlock(&kld_sx);
1504 while ((modptr = preload_search_next_name(modptr)) != NULL) {
1505 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
1506 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE);
1507 if (modname == NULL) {
1508 printf("Preloaded module at %p does not have a"
1509 " name!\n", modptr);
1510 continue;
1511 }
1512 if (modtype == NULL) {
1513 printf("Preloaded module at %p does not have a type!\n",
1514 modptr);
1515 continue;
1516 }
1517 if (bootverbose)
1518 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname,
1519 modptr);
1520 lf = NULL;
1521 TAILQ_FOREACH(lc, &classes, link) {
1522 error = LINKER_LINK_PRELOAD(lc, modname, &lf);
1523 if (!error)
1524 break;
1525 lf = NULL;
1526 }
1527 if (lf)
1528 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded);
1529 }
1530
1531 /*
1532 * First get a list of stuff in the kernel.
1533 */
1534 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start,
1535 &stop, NULL) == 0)
1536 linker_addmodules(linker_kernel_file, start, stop, 1);
1537
1538 /*
1539 * This is a once-off kinky bubble sort to resolve relocation
1540 * dependency requirements.
1541 */
1542 restart:
1543 TAILQ_FOREACH(lf, &loaded_files, loaded) {
1544 error = linker_file_lookup_set(lf, MDT_SETNAME, &start,
1545 &stop, NULL);
1546 /*
1547 * First, look to see if we would successfully link with this
1548 * stuff.
1549 */
1550 resolves = 1; /* unless we know otherwise */
1551 if (!error) {
1552 for (mdp = start; mdp < stop; mdp++) {
1553 mp = *mdp;
1554 if (mp->md_type != MDT_DEPEND)
1555 continue;
1556 modname = mp->md_cval;
1557 verinfo = mp->md_data;
1558 for (nmdp = start; nmdp < stop; nmdp++) {
1559 nmp = *nmdp;
1560 if (nmp->md_type != MDT_VERSION)
1561 continue;
1562 nmodname = nmp->md_cval;
1563 if (strcmp(modname, nmodname) == 0)
1564 break;
1565 }
1566 if (nmdp < stop) /* it's a self reference */
1567 continue;
1568
1569 /*
1570 * ok, the module isn't here yet, we
1571 * are not finished
1572 */
1573 if (modlist_lookup2(modname, verinfo) == NULL)
1574 resolves = 0;
1575 }
1576 }
1577 /*
1578 * OK, if we found our modules, we can link. So, "provide"
1579 * the modules inside and add it to the end of the link order
1580 * list.
1581 */
1582 if (resolves) {
1583 if (!error) {
1584 for (mdp = start; mdp < stop; mdp++) {
1585 mp = *mdp;
1586 if (mp->md_type != MDT_VERSION)
1587 continue;
1588 modname = mp->md_cval;
1589 nver = ((const struct mod_version *)
1590 mp->md_data)->mv_version;
1591 if (modlist_lookup(modname,
1592 nver) != NULL) {
1593 printf("module %s already"
1594 " present!\n", modname);
1595 TAILQ_REMOVE(&loaded_files,
1596 lf, loaded);
1597 linker_file_unload(lf,
1598 LINKER_UNLOAD_FORCE);
1599 /* we changed tailq next ptr */
1600 goto restart;
1601 }
1602 modlist_newmodule(modname, nver, lf);
1603 }
1604 }
1605 TAILQ_REMOVE(&loaded_files, lf, loaded);
1606 TAILQ_INSERT_TAIL(&depended_files, lf, loaded);
1607 /*
1608 * Since we provided modules, we need to restart the
1609 * sort so that the previous files that depend on us
1610 * have a chance. Also, we've busted the tailq next
1611 * pointer with the REMOVE.
1612 */
1613 goto restart;
1614 }
1615 }
1616
1617 /*
1618 * At this point, we check to see what could not be resolved..
1619 */
1620 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) {
1621 TAILQ_REMOVE(&loaded_files, lf, loaded);
1622 printf("KLD file %s is missing dependencies\n", lf->filename);
1623 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1624 }
1625
1626 /*
1627 * We made it. Finish off the linking in the order we determined.
1628 */
1629 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) {
1630 if (linker_kernel_file) {
1631 linker_kernel_file->refs++;
1632 error = linker_file_add_dependency(lf,
1633 linker_kernel_file);
1634 if (error)
1635 panic("cannot add dependency");
1636 }
1637 error = linker_file_lookup_set(lf, MDT_SETNAME, &start,
1638 &stop, NULL);
1639 if (!error) {
1640 for (mdp = start; mdp < stop; mdp++) {
1641 mp = *mdp;
1642 if (mp->md_type != MDT_DEPEND)
1643 continue;
1644 modname = mp->md_cval;
1645 verinfo = mp->md_data;
1646 mod = modlist_lookup2(modname, verinfo);
1647 if (mod == NULL) {
1648 printf("KLD file %s - cannot find "
1649 "dependency \"%s\"\n",
1650 lf->filename, modname);
1651 goto fail;
1652 }
1653 /* Don't count self-dependencies */
1654 if (lf == mod->container)
1655 continue;
1656 mod->container->refs++;
1657 error = linker_file_add_dependency(lf,
1658 mod->container);
1659 if (error)
1660 panic("cannot add dependency");
1661 }
1662 }
1663 /*
1664 * Now do relocation etc using the symbol search paths
1665 * established by the dependencies
1666 */
1667 error = LINKER_LINK_PRELOAD_FINISH(lf);
1668 if (error) {
1669 printf("KLD file %s - could not finalize loading\n",
1670 lf->filename);
1671 goto fail;
1672 }
1673 linker_file_register_modules(lf);
1674 if (!TAILQ_EMPTY(&lf->modules))
1675 lf->flags |= LINKER_FILE_MODULES;
1676 if (linker_file_lookup_set(lf, "sysinit_set", &si_start,
1677 &si_stop, NULL) == 0)
1678 sysinit_add(si_start, si_stop);
1679 linker_file_register_sysctls(lf, true);
1680 lf->flags |= LINKER_FILE_LINKED;
1681 continue;
1682 fail:
1683 TAILQ_REMOVE(&depended_files, lf, loaded);
1684 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1685 }
1686 sx_xunlock(&kld_sx);
1687 /* woohoo! we made it! */
1688 }
1689
1690 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, NULL);
1691
1692 /*
1693 * Handle preload files that failed to load any modules.
1694 */
1695 static void
1696 linker_preload_finish(void *arg)
1697 {
1698 linker_file_t lf, nlf;
1699
1700 sx_xlock(&kld_sx);
1701 TAILQ_FOREACH_SAFE(lf, &linker_files, link, nlf) {
1702 /*
1703 * If all of the modules in this file failed to load, unload
1704 * the file and return an error of ENOEXEC. (Parity with
1705 * linker_load_file.)
1706 */
1707 if ((lf->flags & LINKER_FILE_MODULES) != 0 &&
1708 TAILQ_EMPTY(&lf->modules)) {
1709 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1710 continue;
1711 }
1712
1713 lf->flags &= ~LINKER_FILE_MODULES;
1714 lf->userrefs++; /* so we can (try to) kldunload it */
1715 }
1716 sx_xunlock(&kld_sx);
1717 }
1718
1719 /*
1720 * Attempt to run after all DECLARE_MODULE SYSINITs. Unfortunately they can be
1721 * scheduled at any subsystem and order, so run this as late as possible. init
1722 * becomes runnable in SI_SUB_KTHREAD_INIT, so go slightly before that.
1723 */
1724 SYSINIT(preload_finish, SI_SUB_KTHREAD_INIT - 100, SI_ORDER_MIDDLE,
1725 linker_preload_finish, NULL);
1726
1727 /*
1728 * Search for a not-loaded module by name.
1729 *
1730 * Modules may be found in the following locations:
1731 *
1732 * - preloaded (result is just the module name) - on disk (result is full path
1733 * to module)
1734 *
1735 * If the module name is qualified in any way (contains path, etc.) the we
1736 * simply return a copy of it.
1737 *
1738 * The search path can be manipulated via sysctl. Note that we use the ';'
1739 * character as a separator to be consistent with the bootloader.
1740 */
1741
1742 static char linker_hintfile[] = "linker.hints";
1743 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules";
1744
1745 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RWTUN, linker_path,
1746 sizeof(linker_path), "module load search path");
1747
1748 TUNABLE_STR("module_path", linker_path, sizeof(linker_path));
1749
1750 static char *linker_ext_list[] = {
1751 "",
1752 ".ko",
1753 NULL
1754 };
1755
1756 /*
1757 * Check if file actually exists either with or without extension listed in
1758 * the linker_ext_list. (probably should be generic for the rest of the
1759 * kernel)
1760 */
1761 static char *
1762 linker_lookup_file(const char *path, int pathlen, const char *name,
1763 int namelen, struct vattr *vap)
1764 {
1765 struct nameidata nd;
1766 struct thread *td = curthread; /* XXX */
1767 char *result, **cpp, *sep;
1768 int error, len, extlen, reclen, flags;
1769 enum vtype type;
1770
1771 extlen = 0;
1772 for (cpp = linker_ext_list; *cpp; cpp++) {
1773 len = strlen(*cpp);
1774 if (len > extlen)
1775 extlen = len;
1776 }
1777 extlen++; /* trailing '\0' */
1778 sep = (path[pathlen - 1] != '/') ? "/" : "";
1779
1780 reclen = pathlen + strlen(sep) + namelen + extlen + 1;
1781 result = malloc(reclen, M_LINKER, M_WAITOK);
1782 for (cpp = linker_ext_list; *cpp; cpp++) {
1783 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep,
1784 namelen, name, *cpp);
1785 /*
1786 * Attempt to open the file, and return the path if
1787 * we succeed and it's a regular file.
1788 */
1789 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td);
1790 flags = FREAD;
1791 error = vn_open(&nd, &flags, 0, NULL);
1792 if (error == 0) {
1793 NDFREE(&nd, NDF_ONLY_PNBUF);
1794 type = nd.ni_vp->v_type;
1795 if (vap)
1796 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred);
1797 VOP_UNLOCK(nd.ni_vp, 0);
1798 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
1799 if (type == VREG)
1800 return (result);
1801 }
1802 }
1803 free(result, M_LINKER);
1804 return (NULL);
1805 }
1806
1807 #define INT_ALIGN(base, ptr) ptr = \
1808 (base) + roundup2((ptr) - (base), sizeof(int))
1809
1810 /*
1811 * Lookup KLD which contains requested module in the "linker.hints" file. If
1812 * version specification is available, then try to find the best KLD.
1813 * Otherwise just find the latest one.
1814 */
1815 static char *
1816 linker_hints_lookup(const char *path, int pathlen, const char *modname,
1817 int modnamelen, const struct mod_depend *verinfo)
1818 {
1819 struct thread *td = curthread; /* XXX */
1820 struct ucred *cred = td ? td->td_ucred : NULL;
1821 struct nameidata nd;
1822 struct vattr vattr, mattr;
1823 u_char *hints = NULL;
1824 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep;
1825 int error, ival, bestver, *intp, found, flags, clen, blen;
1826 ssize_t reclen;
1827
1828 result = NULL;
1829 bestver = found = 0;
1830
1831 sep = (path[pathlen - 1] != '/') ? "/" : "";
1832 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen +
1833 strlen(sep) + 1;
1834 pathbuf = malloc(reclen, M_LINKER, M_WAITOK);
1835 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep,
1836 linker_hintfile);
1837
1838 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td);
1839 flags = FREAD;
1840 error = vn_open(&nd, &flags, 0, NULL);
1841 if (error)
1842 goto bad;
1843 NDFREE(&nd, NDF_ONLY_PNBUF);
1844 if (nd.ni_vp->v_type != VREG)
1845 goto bad;
1846 best = cp = NULL;
1847 error = VOP_GETATTR(nd.ni_vp, &vattr, cred);
1848 if (error)
1849 goto bad;
1850 /*
1851 * XXX: we need to limit this number to some reasonable value
1852 */
1853 if (vattr.va_size > LINKER_HINTS_MAX) {
1854 printf("hints file too large %ld\n", (long)vattr.va_size);
1855 goto bad;
1856 }
1857 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK);
1858 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0,
1859 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td);
1860 if (error)
1861 goto bad;
1862 VOP_UNLOCK(nd.ni_vp, 0);
1863 vn_close(nd.ni_vp, FREAD, cred, td);
1864 nd.ni_vp = NULL;
1865 if (reclen != 0) {
1866 printf("can't read %zd\n", reclen);
1867 goto bad;
1868 }
1869 intp = (int *)hints;
1870 ival = *intp++;
1871 if (ival != LINKER_HINTS_VERSION) {
1872 printf("hints file version mismatch %d\n", ival);
1873 goto bad;
1874 }
1875 bufend = hints + vattr.va_size;
1876 recptr = (u_char *)intp;
1877 clen = blen = 0;
1878 while (recptr < bufend && !found) {
1879 intp = (int *)recptr;
1880 reclen = *intp++;
1881 ival = *intp++;
1882 cp = (char *)intp;
1883 switch (ival) {
1884 case MDT_VERSION:
1885 clen = *cp++;
1886 if (clen != modnamelen || bcmp(cp, modname, clen) != 0)
1887 break;
1888 cp += clen;
1889 INT_ALIGN(hints, cp);
1890 ival = *(int *)cp;
1891 cp += sizeof(int);
1892 clen = *cp++;
1893 if (verinfo == NULL ||
1894 ival == verinfo->md_ver_preferred) {
1895 found = 1;
1896 break;
1897 }
1898 if (ival >= verinfo->md_ver_minimum &&
1899 ival <= verinfo->md_ver_maximum &&
1900 ival > bestver) {
1901 bestver = ival;
1902 best = cp;
1903 blen = clen;
1904 }
1905 break;
1906 default:
1907 break;
1908 }
1909 recptr += reclen + sizeof(int);
1910 }
1911 /*
1912 * Finally check if KLD is in the place
1913 */
1914 if (found)
1915 result = linker_lookup_file(path, pathlen, cp, clen, &mattr);
1916 else if (best)
1917 result = linker_lookup_file(path, pathlen, best, blen, &mattr);
1918
1919 /*
1920 * KLD is newer than hints file. What we should do now?
1921 */
1922 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >))
1923 printf("warning: KLD '%s' is newer than the linker.hints"
1924 " file\n", result);
1925 bad:
1926 free(pathbuf, M_LINKER);
1927 if (hints)
1928 free(hints, M_TEMP);
1929 if (nd.ni_vp != NULL) {
1930 VOP_UNLOCK(nd.ni_vp, 0);
1931 vn_close(nd.ni_vp, FREAD, cred, td);
1932 }
1933 /*
1934 * If nothing found or hints is absent - fallback to the old
1935 * way by using "kldname[.ko]" as module name.
1936 */
1937 if (!found && !bestver && result == NULL)
1938 result = linker_lookup_file(path, pathlen, modname,
1939 modnamelen, NULL);
1940 return (result);
1941 }
1942
1943 /*
1944 * Lookup KLD which contains requested module in the all directories.
1945 */
1946 static char *
1947 linker_search_module(const char *modname, int modnamelen,
1948 const struct mod_depend *verinfo)
1949 {
1950 char *cp, *ep, *result;
1951
1952 /*
1953 * traverse the linker path
1954 */
1955 for (cp = linker_path; *cp; cp = ep + 1) {
1956 /* find the end of this component */
1957 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++);
1958 result = linker_hints_lookup(cp, ep - cp, modname,
1959 modnamelen, verinfo);
1960 if (result != NULL)
1961 return (result);
1962 if (*ep == 0)
1963 break;
1964 }
1965 return (NULL);
1966 }
1967
1968 /*
1969 * Search for module in all directories listed in the linker_path.
1970 */
1971 static char *
1972 linker_search_kld(const char *name)
1973 {
1974 char *cp, *ep, *result;
1975 int len;
1976
1977 /* qualified at all? */
1978 if (strchr(name, '/'))
1979 return (strdup(name, M_LINKER));
1980
1981 /* traverse the linker path */
1982 len = strlen(name);
1983 for (ep = linker_path; *ep; ep++) {
1984 cp = ep;
1985 /* find the end of this component */
1986 for (; *ep != 0 && *ep != ';'; ep++);
1987 result = linker_lookup_file(cp, ep - cp, name, len, NULL);
1988 if (result != NULL)
1989 return (result);
1990 }
1991 return (NULL);
1992 }
1993
1994 static const char *
1995 linker_basename(const char *path)
1996 {
1997 const char *filename;
1998
1999 filename = strrchr(path, '/');
2000 if (filename == NULL)
2001 return path;
2002 if (filename[1])
2003 filename++;
2004 return (filename);
2005 }
2006
2007 #ifdef HWPMC_HOOKS
2008 /*
2009 * Inform hwpmc about the set of kernel modules currently loaded.
2010 */
2011 void *
2012 linker_hwpmc_list_objects(void)
2013 {
2014 linker_file_t lf;
2015 struct pmckern_map_in *kobase;
2016 int i, nmappings;
2017
2018 nmappings = 0;
2019 sx_slock(&kld_sx);
2020 TAILQ_FOREACH(lf, &linker_files, link)
2021 nmappings++;
2022
2023 /* Allocate nmappings + 1 entries. */
2024 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in),
2025 M_LINKER, M_WAITOK | M_ZERO);
2026 i = 0;
2027 TAILQ_FOREACH(lf, &linker_files, link) {
2028
2029 /* Save the info for this linker file. */
2030 kobase[i].pm_file = lf->filename;
2031 kobase[i].pm_address = (uintptr_t)lf->address;
2032 i++;
2033 }
2034 sx_sunlock(&kld_sx);
2035
2036 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?"));
2037
2038 /* The last entry of the malloced area comprises of all zeros. */
2039 KASSERT(kobase[i].pm_file == NULL,
2040 ("linker_hwpmc_list_objects: last object not NULL"));
2041
2042 return ((void *)kobase);
2043 }
2044 #endif
2045
2046 /*
2047 * Find a file which contains given module and load it, if "parent" is not
2048 * NULL, register a reference to it.
2049 */
2050 static int
2051 linker_load_module(const char *kldname, const char *modname,
2052 struct linker_file *parent, const struct mod_depend *verinfo,
2053 struct linker_file **lfpp)
2054 {
2055 linker_file_t lfdep;
2056 const char *filename;
2057 char *pathname;
2058 int error;
2059
2060 sx_assert(&kld_sx, SA_XLOCKED);
2061 if (modname == NULL) {
2062 /*
2063 * We have to load KLD
2064 */
2065 KASSERT(verinfo == NULL, ("linker_load_module: verinfo"
2066 " is not NULL"));
2067 /* check if root file system is not mounted */
2068 if (rootvnode == NULL || curproc->p_fd->fd_rdir == NULL)
2069 return (ENXIO);
2070 pathname = linker_search_kld(kldname);
2071 } else {
2072 if (modlist_lookup2(modname, verinfo) != NULL)
2073 return (EEXIST);
2074 /* check if root file system is not mounted */
2075 if (rootvnode == NULL || curproc->p_fd->fd_rdir == NULL)
2076 return (ENXIO);
2077 if (kldname != NULL)
2078 pathname = strdup(kldname, M_LINKER);
2079 else
2080 /*
2081 * Need to find a KLD with required module
2082 */
2083 pathname = linker_search_module(modname,
2084 strlen(modname), verinfo);
2085 }
2086 if (pathname == NULL)
2087 return (ENOENT);
2088
2089 /*
2090 * Can't load more than one file with the same basename XXX:
2091 * Actually it should be possible to have multiple KLDs with
2092 * the same basename but different path because they can
2093 * provide different versions of the same modules.
2094 */
2095 filename = linker_basename(pathname);
2096 if (linker_find_file_by_name(filename))
2097 error = EEXIST;
2098 else do {
2099 error = linker_load_file(pathname, &lfdep);
2100 if (error)
2101 break;
2102 if (modname && verinfo &&
2103 modlist_lookup2(modname, verinfo) == NULL) {
2104 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE);
2105 error = ENOENT;
2106 break;
2107 }
2108 if (parent) {
2109 error = linker_file_add_dependency(parent, lfdep);
2110 if (error)
2111 break;
2112 }
2113 if (lfpp)
2114 *lfpp = lfdep;
2115 } while (0);
2116 free(pathname, M_LINKER);
2117 return (error);
2118 }
2119
2120 /*
2121 * This routine is responsible for finding dependencies of userland initiated
2122 * kldload(2)'s of files.
2123 */
2124 int
2125 linker_load_dependencies(linker_file_t lf)
2126 {
2127 linker_file_t lfdep;
2128 struct mod_metadata **start, **stop, **mdp, **nmdp;
2129 struct mod_metadata *mp, *nmp;
2130 const struct mod_depend *verinfo;
2131 modlist_t mod;
2132 const char *modname, *nmodname;
2133 int ver, error = 0;
2134
2135 /*
2136 * All files are dependent on /kernel.
2137 */
2138 sx_assert(&kld_sx, SA_XLOCKED);
2139 if (linker_kernel_file) {
2140 linker_kernel_file->refs++;
2141 error = linker_file_add_dependency(lf, linker_kernel_file);
2142 if (error)
2143 return (error);
2144 }
2145 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop,
2146 NULL) != 0)
2147 return (0);
2148 for (mdp = start; mdp < stop; mdp++) {
2149 mp = *mdp;
2150 if (mp->md_type != MDT_VERSION)
2151 continue;
2152 modname = mp->md_cval;
2153 ver = ((const struct mod_version *)mp->md_data)->mv_version;
2154 mod = modlist_lookup(modname, ver);
2155 if (mod != NULL) {
2156 printf("interface %s.%d already present in the KLD"
2157 " '%s'!\n", modname, ver,
2158 mod->container->filename);
2159 return (EEXIST);
2160 }
2161 }
2162
2163 for (mdp = start; mdp < stop; mdp++) {
2164 mp = *mdp;
2165 if (mp->md_type != MDT_DEPEND)
2166 continue;
2167 modname = mp->md_cval;
2168 verinfo = mp->md_data;
2169 nmodname = NULL;
2170 for (nmdp = start; nmdp < stop; nmdp++) {
2171 nmp = *nmdp;
2172 if (nmp->md_type != MDT_VERSION)
2173 continue;
2174 nmodname = nmp->md_cval;
2175 if (strcmp(modname, nmodname) == 0)
2176 break;
2177 }
2178 if (nmdp < stop)/* early exit, it's a self reference */
2179 continue;
2180 mod = modlist_lookup2(modname, verinfo);
2181 if (mod) { /* woohoo, it's loaded already */
2182 lfdep = mod->container;
2183 lfdep->refs++;
2184 error = linker_file_add_dependency(lf, lfdep);
2185 if (error)
2186 break;
2187 continue;
2188 }
2189 error = linker_load_module(NULL, modname, lf, verinfo, NULL);
2190 if (error) {
2191 printf("KLD %s: depends on %s - not available or"
2192 " version mismatch\n", lf->filename, modname);
2193 break;
2194 }
2195 }
2196
2197 if (error)
2198 return (error);
2199 linker_addmodules(lf, start, stop, 0);
2200 return (error);
2201 }
2202
2203 static int
2204 sysctl_kern_function_list_iterate(const char *name, void *opaque)
2205 {
2206 struct sysctl_req *req;
2207
2208 req = opaque;
2209 return (SYSCTL_OUT(req, name, strlen(name) + 1));
2210 }
2211
2212 /*
2213 * Export a nul-separated, double-nul-terminated list of all function names
2214 * in the kernel.
2215 */
2216 static int
2217 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS)
2218 {
2219 linker_file_t lf;
2220 int error;
2221
2222 #ifdef MAC
2223 error = mac_kld_check_stat(req->td->td_ucred);
2224 if (error)
2225 return (error);
2226 #endif
2227 error = sysctl_wire_old_buffer(req, 0);
2228 if (error != 0)
2229 return (error);
2230 sx_xlock(&kld_sx);
2231 TAILQ_FOREACH(lf, &linker_files, link) {
2232 error = LINKER_EACH_FUNCTION_NAME(lf,
2233 sysctl_kern_function_list_iterate, req);
2234 if (error) {
2235 sx_xunlock(&kld_sx);
2236 return (error);
2237 }
2238 }
2239 sx_xunlock(&kld_sx);
2240 return (SYSCTL_OUT(req, "", 1));
2241 }
2242
2243 SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLTYPE_OPAQUE | CTLFLAG_RD,
2244 NULL, 0, sysctl_kern_function_list, "", "kernel function list");
Cache object: b28326c60a22a093e5a62158e95368fc
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