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