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