1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 1997-2000 Doug Rabson 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 #include "opt_ddb.h" 31 #include "opt_kld.h" 32 #include "opt_hwpmc_hooks.h" 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/boottrace.h> 37 #include <sys/eventhandler.h> 38 #include <sys/fcntl.h> 39 #include <sys/jail.h> 40 #include <sys/kernel.h> 41 #include <sys/libkern.h> 42 #include <sys/linker.h> 43 #include <sys/lock.h> 44 #include <sys/malloc.h> 45 #include <sys/module.h> 46 #include <sys/mount.h> 47 #include <sys/mutex.h> 48 #include <sys/namei.h> 49 #include <sys/priv.h> 50 #include <sys/proc.h> 51 #include <sys/sx.h> 52 #include <sys/syscallsubr.h> 53 #include <sys/sysctl.h> 54 #include <sys/sysproto.h> 55 #include <sys/vnode.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 static u_int kld_busy; 108 static struct thread *kld_busy_owner; 109 110 /* 111 * Load counter used by clients to determine if a linker file has been 112 * re-loaded. This counter is incremented for each file load. 113 */ 114 static int loadcnt; 115 116 static linker_class_list_t classes; 117 static linker_file_list_t linker_files; 118 static int next_file_id = 1; 119 static int linker_no_more_classes = 0; 120 121 #define LINKER_GET_NEXT_FILE_ID(a) do { \ 122 linker_file_t lftmp; \ 123 \ 124 if (!cold) \ 125 sx_assert(&kld_sx, SA_XLOCKED); \ 126 retry: \ 127 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 128 if (next_file_id == lftmp->id) { \ 129 next_file_id++; \ 130 goto retry; \ 131 } \ 132 } \ 133 (a) = next_file_id; \ 134 } while (0) 135 136 /* XXX wrong name; we're looking at version provision tags here, not modules */ 137 typedef TAILQ_HEAD(, modlist) modlisthead_t; 138 struct modlist { 139 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 140 linker_file_t container; 141 const char *name; 142 int version; 143 }; 144 typedef struct modlist *modlist_t; 145 static modlisthead_t found_modules; 146 147 static int linker_file_add_dependency(linker_file_t file, 148 linker_file_t dep); 149 static caddr_t linker_file_lookup_symbol_internal(linker_file_t file, 150 const char* name, int deps); 151 static int linker_load_module(const char *kldname, 152 const char *modname, struct linker_file *parent, 153 const struct mod_depend *verinfo, struct linker_file **lfpp); 154 static modlist_t modlist_lookup2(const char *name, const struct mod_depend *verinfo); 155 156 static void 157 linker_init(void *arg) 158 { 159 160 sx_init(&kld_sx, "kernel linker"); 161 TAILQ_INIT(&classes); 162 TAILQ_INIT(&linker_files); 163 } 164 165 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, NULL); 166 167 static void 168 linker_stop_class_add(void *arg) 169 { 170 171 linker_no_more_classes = 1; 172 } 173 174 SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL); 175 176 int 177 linker_add_class(linker_class_t lc) 178 { 179 180 /* 181 * We disallow any class registration past SI_ORDER_ANY 182 * of SI_SUB_KLD. We bump the reference count to keep the 183 * ops from being freed. 184 */ 185 if (linker_no_more_classes == 1) 186 return (EPERM); 187 kobj_class_compile((kobj_class_t) lc); 188 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */ 189 TAILQ_INSERT_TAIL(&classes, lc, link); 190 return (0); 191 } 192 193 static void 194 linker_file_sysinit(linker_file_t lf) 195 { 196 struct sysinit **start, **stop, **sipp, **xipp, *save; 197 int last; 198 199 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 200 lf->filename)); 201 202 sx_assert(&kld_sx, SA_XLOCKED); 203 204 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 205 return; 206 /* 207 * Perform a bubble sort of the system initialization objects by 208 * their subsystem (primary key) and order (secondary key). 209 * 210 * Since some things care about execution order, this is the operation 211 * which ensures continued function. 212 */ 213 for (sipp = start; sipp < stop; sipp++) { 214 for (xipp = sipp + 1; xipp < stop; xipp++) { 215 if ((*sipp)->subsystem < (*xipp)->subsystem || 216 ((*sipp)->subsystem == (*xipp)->subsystem && 217 (*sipp)->order <= (*xipp)->order)) 218 continue; /* skip */ 219 save = *sipp; 220 *sipp = *xipp; 221 *xipp = save; 222 } 223 } 224 225 /* 226 * Traverse the (now) ordered list of system initialization tasks. 227 * Perform each task, and continue on to the next task. 228 */ 229 last = SI_SUB_DUMMY; 230 sx_xunlock(&kld_sx); 231 mtx_lock(&Giant); 232 for (sipp = start; sipp < stop; sipp++) { 233 if ((*sipp)->subsystem == SI_SUB_DUMMY) 234 continue; /* skip dummy task(s) */ 235 236 if ((*sipp)->subsystem > last) 237 BOOTTRACE("%s: sysinit 0x%7x", lf->filename, 238 (*sipp)->subsystem); 239 240 /* Call function */ 241 (*((*sipp)->func)) ((*sipp)->udata); 242 last = (*sipp)->subsystem; 243 } 244 mtx_unlock(&Giant); 245 sx_xlock(&kld_sx); 246 } 247 248 static void 249 linker_file_sysuninit(linker_file_t lf) 250 { 251 struct sysinit **start, **stop, **sipp, **xipp, *save; 252 int last; 253 254 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 255 lf->filename)); 256 257 sx_assert(&kld_sx, SA_XLOCKED); 258 259 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 260 NULL) != 0) 261 return; 262 263 /* 264 * Perform a reverse bubble sort of the system initialization objects 265 * by their subsystem (primary key) and order (secondary key). 266 * 267 * Since some things care about execution order, this is the operation 268 * which ensures continued function. 269 */ 270 for (sipp = start; sipp < stop; sipp++) { 271 for (xipp = sipp + 1; xipp < stop; xipp++) { 272 if ((*sipp)->subsystem > (*xipp)->subsystem || 273 ((*sipp)->subsystem == (*xipp)->subsystem && 274 (*sipp)->order >= (*xipp)->order)) 275 continue; /* skip */ 276 save = *sipp; 277 *sipp = *xipp; 278 *xipp = save; 279 } 280 } 281 282 /* 283 * Traverse the (now) ordered list of system initialization tasks. 284 * Perform each task, and continue on to the next task. 285 */ 286 sx_xunlock(&kld_sx); 287 mtx_lock(&Giant); 288 last = SI_SUB_DUMMY; 289 for (sipp = start; sipp < stop; sipp++) { 290 if ((*sipp)->subsystem == SI_SUB_DUMMY) 291 continue; /* skip dummy task(s) */ 292 293 if ((*sipp)->subsystem > last) 294 BOOTTRACE("%s: sysuninit 0x%7x", lf->filename, 295 (*sipp)->subsystem); 296 297 /* Call function */ 298 (*((*sipp)->func)) ((*sipp)->udata); 299 last = (*sipp)->subsystem; 300 } 301 mtx_unlock(&Giant); 302 sx_xlock(&kld_sx); 303 } 304 305 static void 306 linker_file_register_sysctls(linker_file_t lf, bool enable) 307 { 308 struct sysctl_oid **start, **stop, **oidp; 309 310 KLD_DPF(FILE, 311 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 312 lf->filename)); 313 314 sx_assert(&kld_sx, SA_XLOCKED); 315 316 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 317 return; 318 319 sx_xunlock(&kld_sx); 320 sysctl_wlock(); 321 for (oidp = start; oidp < stop; oidp++) { 322 if (enable) 323 sysctl_register_oid(*oidp); 324 else 325 sysctl_register_disabled_oid(*oidp); 326 } 327 sysctl_wunlock(); 328 sx_xlock(&kld_sx); 329 } 330 331 static void 332 linker_file_enable_sysctls(linker_file_t lf) 333 { 334 struct sysctl_oid **start, **stop, **oidp; 335 336 KLD_DPF(FILE, 337 ("linker_file_enable_sysctls: enable SYSCTLs for %s\n", 338 lf->filename)); 339 340 sx_assert(&kld_sx, SA_XLOCKED); 341 342 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 343 return; 344 345 sx_xunlock(&kld_sx); 346 sysctl_wlock(); 347 for (oidp = start; oidp < stop; oidp++) 348 sysctl_enable_oid(*oidp); 349 sysctl_wunlock(); 350 sx_xlock(&kld_sx); 351 } 352 353 static void 354 linker_file_unregister_sysctls(linker_file_t lf) 355 { 356 struct sysctl_oid **start, **stop, **oidp; 357 358 KLD_DPF(FILE, ("linker_file_unregister_sysctls: unregistering SYSCTLs" 359 " for %s\n", lf->filename)); 360 361 sx_assert(&kld_sx, SA_XLOCKED); 362 363 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 364 return; 365 366 sx_xunlock(&kld_sx); 367 sysctl_wlock(); 368 for (oidp = start; oidp < stop; oidp++) 369 sysctl_unregister_oid(*oidp); 370 sysctl_wunlock(); 371 sx_xlock(&kld_sx); 372 } 373 374 static int 375 linker_file_register_modules(linker_file_t lf) 376 { 377 struct mod_metadata **start, **stop, **mdp; 378 const moduledata_t *moddata; 379 int first_error, error; 380 381 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 382 " in %s\n", lf->filename)); 383 384 sx_assert(&kld_sx, SA_XLOCKED); 385 386 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL) != 0) { 387 /* 388 * This fallback should be unnecessary, but if we get booted 389 * from boot2 instead of loader and we are missing our 390 * metadata then we have to try the best we can. 391 */ 392 if (lf == linker_kernel_file) { 393 start = SET_BEGIN(modmetadata_set); 394 stop = SET_LIMIT(modmetadata_set); 395 } else 396 return (0); 397 } 398 first_error = 0; 399 for (mdp = start; mdp < stop; mdp++) { 400 if ((*mdp)->md_type != MDT_MODULE) 401 continue; 402 moddata = (*mdp)->md_data; 403 KLD_DPF(FILE, ("Registering module %s in %s\n", 404 moddata->name, lf->filename)); 405 error = module_register(moddata, lf); 406 if (error) { 407 printf("Module %s failed to register: %d\n", 408 moddata->name, error); 409 if (first_error == 0) 410 first_error = error; 411 } 412 } 413 return (first_error); 414 } 415 416 static void 417 linker_init_kernel_modules(void) 418 { 419 420 sx_xlock(&kld_sx); 421 linker_file_register_modules(linker_kernel_file); 422 sx_xunlock(&kld_sx); 423 } 424 425 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 426 NULL); 427 428 static int 429 linker_load_file(const char *filename, linker_file_t *result) 430 { 431 linker_class_t lc; 432 linker_file_t lf; 433 int foundfile, error, modules; 434 435 /* Refuse to load modules if securelevel raised */ 436 if (prison0.pr_securelevel > 0) 437 return (EPERM); 438 439 sx_assert(&kld_sx, SA_XLOCKED); 440 lf = linker_find_file_by_name(filename); 441 if (lf) { 442 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 443 " incrementing refs\n", filename)); 444 *result = lf; 445 lf->refs++; 446 return (0); 447 } 448 foundfile = 0; 449 error = 0; 450 451 /* 452 * We do not need to protect (lock) classes here because there is 453 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 454 * and there is no class deregistration mechanism at this time. 455 */ 456 TAILQ_FOREACH(lc, &classes, link) { 457 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 458 filename)); 459 error = LINKER_LOAD_FILE(lc, filename, &lf); 460 /* 461 * If we got something other than ENOENT, then it exists but 462 * we cannot load it for some other reason. 463 */ 464 if (error != ENOENT) 465 foundfile = 1; 466 if (lf) { 467 error = linker_file_register_modules(lf); 468 if (error == EEXIST) { 469 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 470 return (error); 471 } 472 modules = !TAILQ_EMPTY(&lf->modules); 473 linker_file_register_sysctls(lf, false); 474 linker_file_sysinit(lf); 475 lf->flags |= LINKER_FILE_LINKED; 476 477 /* 478 * If all of the modules in this file failed 479 * to load, unload the file and return an 480 * error of ENOEXEC. 481 */ 482 if (modules && TAILQ_EMPTY(&lf->modules)) { 483 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 484 return (ENOEXEC); 485 } 486 linker_file_enable_sysctls(lf); 487 EVENTHANDLER_INVOKE(kld_load, lf); 488 *result = lf; 489 return (0); 490 } 491 } 492 /* 493 * Less than ideal, but tells the user whether it failed to load or 494 * the module was not found. 495 */ 496 if (foundfile) { 497 /* 498 * If the file type has not been recognized by the last try 499 * printout a message before to fail. 500 */ 501 if (error == ENOSYS) 502 printf("%s: %s - unsupported file type\n", 503 __func__, filename); 504 505 /* 506 * Format not recognized or otherwise unloadable. 507 * When loading a module that is statically built into 508 * the kernel EEXIST percolates back up as the return 509 * value. Preserve this so that apps like sysinstall 510 * can recognize this special case and not post bogus 511 * dialog boxes. 512 */ 513 if (error != EEXIST) 514 error = ENOEXEC; 515 } else 516 error = ENOENT; /* Nothing found */ 517 return (error); 518 } 519 520 int 521 linker_reference_module(const char *modname, struct mod_depend *verinfo, 522 linker_file_t *result) 523 { 524 modlist_t mod; 525 int error; 526 527 sx_xlock(&kld_sx); 528 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 529 *result = mod->container; 530 (*result)->refs++; 531 sx_xunlock(&kld_sx); 532 return (0); 533 } 534 535 error = linker_load_module(NULL, modname, NULL, verinfo, result); 536 sx_xunlock(&kld_sx); 537 return (error); 538 } 539 540 int 541 linker_release_module(const char *modname, struct mod_depend *verinfo, 542 linker_file_t lf) 543 { 544 modlist_t mod; 545 int error; 546 547 sx_xlock(&kld_sx); 548 if (lf == NULL) { 549 KASSERT(modname != NULL, 550 ("linker_release_module: no file or name")); 551 mod = modlist_lookup2(modname, verinfo); 552 if (mod == NULL) { 553 sx_xunlock(&kld_sx); 554 return (ESRCH); 555 } 556 lf = mod->container; 557 } else 558 KASSERT(modname == NULL && verinfo == NULL, 559 ("linker_release_module: both file and name")); 560 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL); 561 sx_xunlock(&kld_sx); 562 return (error); 563 } 564 565 static linker_file_t 566 linker_find_file_by_name(const char *filename) 567 { 568 linker_file_t lf; 569 char *koname; 570 571 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 572 sprintf(koname, "%s.ko", filename); 573 574 sx_assert(&kld_sx, SA_XLOCKED); 575 TAILQ_FOREACH(lf, &linker_files, link) { 576 if (strcmp(lf->filename, koname) == 0) 577 break; 578 if (strcmp(lf->filename, filename) == 0) 579 break; 580 } 581 free(koname, M_LINKER); 582 return (lf); 583 } 584 585 static linker_file_t 586 linker_find_file_by_id(int fileid) 587 { 588 linker_file_t lf; 589 590 sx_assert(&kld_sx, SA_XLOCKED); 591 TAILQ_FOREACH(lf, &linker_files, link) 592 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED) 593 break; 594 return (lf); 595 } 596 597 int 598 linker_file_foreach(linker_predicate_t *predicate, void *context) 599 { 600 linker_file_t lf; 601 int retval = 0; 602 603 sx_xlock(&kld_sx); 604 TAILQ_FOREACH(lf, &linker_files, link) { 605 retval = predicate(lf, context); 606 if (retval != 0) 607 break; 608 } 609 sx_xunlock(&kld_sx); 610 return (retval); 611 } 612 613 linker_file_t 614 linker_make_file(const char *pathname, linker_class_t lc) 615 { 616 linker_file_t lf; 617 const char *filename; 618 619 if (!cold) 620 sx_assert(&kld_sx, SA_XLOCKED); 621 filename = linker_basename(pathname); 622 623 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname)); 624 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 625 if (lf == NULL) 626 return (NULL); 627 lf->ctors_addr = 0; 628 lf->ctors_size = 0; 629 lf->dtors_addr = 0; 630 lf->dtors_size = 0; 631 lf->refs = 1; 632 lf->userrefs = 0; 633 lf->flags = 0; 634 lf->filename = strdup(filename, M_LINKER); 635 lf->pathname = strdup(pathname, M_LINKER); 636 LINKER_GET_NEXT_FILE_ID(lf->id); 637 lf->ndeps = 0; 638 lf->deps = NULL; 639 lf->loadcnt = ++loadcnt; 640 #ifdef __arm__ 641 lf->exidx_addr = 0; 642 lf->exidx_size = 0; 643 #endif 644 STAILQ_INIT(&lf->common); 645 TAILQ_INIT(&lf->modules); 646 TAILQ_INSERT_TAIL(&linker_files, lf, link); 647 return (lf); 648 } 649 650 int 651 linker_file_unload(linker_file_t file, int flags) 652 { 653 module_t mod, next; 654 modlist_t ml, nextml; 655 struct common_symbol *cp; 656 int error, i; 657 658 /* Refuse to unload modules if securelevel raised. */ 659 if (prison0.pr_securelevel > 0) 660 return (EPERM); 661 662 sx_assert(&kld_sx, SA_XLOCKED); 663 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 664 665 /* Easy case of just dropping a reference. */ 666 if (file->refs > 1) { 667 file->refs--; 668 return (0); 669 } 670 671 /* Give eventhandlers a chance to prevent the unload. */ 672 error = 0; 673 EVENTHANDLER_INVOKE(kld_unload_try, file, &error); 674 if (error != 0) 675 return (EBUSY); 676 677 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 678 " informing modules\n")); 679 680 /* 681 * Quiesce all the modules to give them a chance to veto the unload. 682 */ 683 MOD_SLOCK; 684 for (mod = TAILQ_FIRST(&file->modules); mod; 685 mod = module_getfnext(mod)) { 686 error = module_quiesce(mod); 687 if (error != 0 && flags != LINKER_UNLOAD_FORCE) { 688 KLD_DPF(FILE, ("linker_file_unload: module %s" 689 " vetoed unload\n", module_getname(mod))); 690 /* 691 * XXX: Do we need to tell all the quiesced modules 692 * that they can resume work now via a new module 693 * event? 694 */ 695 MOD_SUNLOCK; 696 return (error); 697 } 698 } 699 MOD_SUNLOCK; 700 701 /* 702 * Inform any modules associated with this file that they are 703 * being unloaded. 704 */ 705 MOD_XLOCK; 706 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 707 next = module_getfnext(mod); 708 MOD_XUNLOCK; 709 710 /* 711 * Give the module a chance to veto the unload. 712 */ 713 if ((error = module_unload(mod)) != 0) { 714 #ifdef KLD_DEBUG 715 MOD_SLOCK; 716 KLD_DPF(FILE, ("linker_file_unload: module %s" 717 " failed unload\n", module_getname(mod))); 718 MOD_SUNLOCK; 719 #endif 720 return (error); 721 } 722 MOD_XLOCK; 723 module_release(mod); 724 } 725 MOD_XUNLOCK; 726 727 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 728 if (ml->container == file) { 729 TAILQ_REMOVE(&found_modules, ml, link); 730 free(ml, M_LINKER); 731 } 732 } 733 734 /* 735 * Don't try to run SYSUNINITs if we are unloaded due to a 736 * link error. 737 */ 738 if (file->flags & LINKER_FILE_LINKED) { 739 file->flags &= ~LINKER_FILE_LINKED; 740 linker_file_unregister_sysctls(file); 741 linker_file_sysuninit(file); 742 } 743 TAILQ_REMOVE(&linker_files, file, link); 744 745 if (file->deps) { 746 for (i = 0; i < file->ndeps; i++) 747 linker_file_unload(file->deps[i], flags); 748 free(file->deps, M_LINKER); 749 file->deps = NULL; 750 } 751 while ((cp = STAILQ_FIRST(&file->common)) != NULL) { 752 STAILQ_REMOVE_HEAD(&file->common, link); 753 free(cp, M_LINKER); 754 } 755 756 LINKER_UNLOAD(file); 757 758 EVENTHANDLER_INVOKE(kld_unload, file->filename, file->address, 759 file->size); 760 761 if (file->filename) { 762 free(file->filename, M_LINKER); 763 file->filename = NULL; 764 } 765 if (file->pathname) { 766 free(file->pathname, M_LINKER); 767 file->pathname = NULL; 768 } 769 kobj_delete((kobj_t) file, M_LINKER); 770 return (0); 771 } 772 773 int 774 linker_ctf_get(linker_file_t file, linker_ctf_t *lc) 775 { 776 return (LINKER_CTF_GET(file, lc)); 777 } 778 779 static int 780 linker_file_add_dependency(linker_file_t file, linker_file_t dep) 781 { 782 linker_file_t *newdeps; 783 784 sx_assert(&kld_sx, SA_XLOCKED); 785 file->deps = realloc(file->deps, (file->ndeps + 1) * sizeof(*newdeps), 786 M_LINKER, M_WAITOK | M_ZERO); 787 file->deps[file->ndeps] = dep; 788 file->ndeps++; 789 KLD_DPF(FILE, ("linker_file_add_dependency:" 790 " adding %s as dependency for %s\n", 791 dep->filename, file->filename)); 792 return (0); 793 } 794 795 /* 796 * Locate a linker set and its contents. This is a helper function to avoid 797 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **. 798 * This function is used in this file so we can avoid having lots of (void **) 799 * casts. 800 */ 801 int 802 linker_file_lookup_set(linker_file_t file, const char *name, 803 void *firstp, void *lastp, int *countp) 804 { 805 806 sx_assert(&kld_sx, SA_LOCKED); 807 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 808 } 809 810 /* 811 * List all functions in a file. 812 */ 813 int 814 linker_file_function_listall(linker_file_t lf, 815 linker_function_nameval_callback_t callback_func, void *arg) 816 { 817 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg)); 818 } 819 820 caddr_t 821 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 822 { 823 caddr_t sym; 824 int locked; 825 826 locked = sx_xlocked(&kld_sx); 827 if (!locked) 828 sx_xlock(&kld_sx); 829 sym = linker_file_lookup_symbol_internal(file, name, deps); 830 if (!locked) 831 sx_xunlock(&kld_sx); 832 return (sym); 833 } 834 835 static caddr_t 836 linker_file_lookup_symbol_internal(linker_file_t file, const char *name, 837 int deps) 838 { 839 c_linker_sym_t sym; 840 linker_symval_t symval; 841 caddr_t address; 842 size_t common_size = 0; 843 int i; 844 845 sx_assert(&kld_sx, SA_XLOCKED); 846 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 847 file, name, deps)); 848 849 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 850 LINKER_SYMBOL_VALUES(file, sym, &symval); 851 if (symval.value == 0) 852 /* 853 * For commons, first look them up in the 854 * dependencies and only allocate space if not found 855 * there. 856 */ 857 common_size = symval.size; 858 else { 859 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 860 ".value=%p\n", symval.value)); 861 return (symval.value); 862 } 863 } 864 if (deps) { 865 for (i = 0; i < file->ndeps; i++) { 866 address = linker_file_lookup_symbol_internal( 867 file->deps[i], name, 0); 868 if (address) { 869 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 870 " deps value=%p\n", address)); 871 return (address); 872 } 873 } 874 } 875 if (common_size > 0) { 876 /* 877 * This is a common symbol which was not found in the 878 * dependencies. We maintain a simple common symbol table in 879 * the file object. 880 */ 881 struct common_symbol *cp; 882 883 STAILQ_FOREACH(cp, &file->common, link) { 884 if (strcmp(cp->name, name) == 0) { 885 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 886 " old common value=%p\n", cp->address)); 887 return (cp->address); 888 } 889 } 890 /* 891 * Round the symbol size up to align. 892 */ 893 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 894 cp = malloc(sizeof(struct common_symbol) 895 + common_size + strlen(name) + 1, M_LINKER, 896 M_WAITOK | M_ZERO); 897 cp->address = (caddr_t)(cp + 1); 898 cp->name = cp->address + common_size; 899 strcpy(cp->name, name); 900 bzero(cp->address, common_size); 901 STAILQ_INSERT_TAIL(&file->common, cp, link); 902 903 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 904 " value=%p\n", cp->address)); 905 return (cp->address); 906 } 907 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 908 return (0); 909 } 910 911 /* 912 * Both DDB and stack(9) rely on the kernel linker to provide forward and 913 * backward lookup of symbols. However, DDB and sometimes stack(9) need to 914 * do this in a lockfree manner. We provide a set of internal helper 915 * routines to perform these operations without locks, and then wrappers that 916 * optionally lock. 917 * 918 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB. 919 */ 920 #ifdef DDB 921 static int 922 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym) 923 { 924 linker_file_t lf; 925 926 TAILQ_FOREACH(lf, &linker_files, link) { 927 if (LINKER_LOOKUP_DEBUG_SYMBOL(lf, symstr, sym) == 0) 928 return (0); 929 } 930 return (ENOENT); 931 } 932 #endif 933 934 static int 935 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 936 { 937 linker_file_t lf; 938 c_linker_sym_t best, es; 939 u_long diff, bestdiff, off; 940 941 best = 0; 942 off = (uintptr_t)value; 943 bestdiff = off; 944 TAILQ_FOREACH(lf, &linker_files, link) { 945 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 946 continue; 947 if (es != 0 && diff < bestdiff) { 948 best = es; 949 bestdiff = diff; 950 } 951 if (bestdiff == 0) 952 break; 953 } 954 if (best) { 955 *sym = best; 956 *diffp = bestdiff; 957 return (0); 958 } else { 959 *sym = 0; 960 *diffp = off; 961 return (ENOENT); 962 } 963 } 964 965 static int 966 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 967 { 968 linker_file_t lf; 969 970 TAILQ_FOREACH(lf, &linker_files, link) { 971 if (LINKER_DEBUG_SYMBOL_VALUES(lf, sym, symval) == 0) 972 return (0); 973 } 974 return (ENOENT); 975 } 976 977 static int 978 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen, 979 long *offset) 980 { 981 linker_symval_t symval; 982 c_linker_sym_t sym; 983 int error; 984 985 *offset = 0; 986 error = linker_debug_search_symbol(value, &sym, offset); 987 if (error) 988 return (error); 989 error = linker_debug_symbol_values(sym, &symval); 990 if (error) 991 return (error); 992 strlcpy(buf, symval.name, buflen); 993 return (0); 994 } 995 996 /* 997 * DDB Helpers. DDB has to look across multiple files with their own symbol 998 * tables and string tables. 999 * 1000 * Note that we do not obey list locking protocols here. We really don't need 1001 * DDB to hang because somebody's got the lock held. We'll take the chance 1002 * that the files list is inconsistent instead. 1003 */ 1004 #ifdef DDB 1005 int 1006 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 1007 { 1008 1009 return (linker_debug_lookup(symstr, sym)); 1010 } 1011 #endif 1012 1013 int 1014 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 1015 { 1016 1017 return (linker_debug_search_symbol(value, sym, diffp)); 1018 } 1019 1020 int 1021 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 1022 { 1023 1024 return (linker_debug_symbol_values(sym, symval)); 1025 } 1026 1027 int 1028 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1029 long *offset) 1030 { 1031 1032 return (linker_debug_search_symbol_name(value, buf, buflen, offset)); 1033 } 1034 1035 /* 1036 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do 1037 * obey locking protocols, and offer a significantly less complex interface. 1038 */ 1039 int 1040 linker_search_symbol_name_flags(caddr_t value, char *buf, u_int buflen, 1041 long *offset, int flags) 1042 { 1043 int error; 1044 1045 KASSERT((flags & (M_NOWAIT | M_WAITOK)) != 0 && 1046 (flags & (M_NOWAIT | M_WAITOK)) != (M_NOWAIT | M_WAITOK), 1047 ("%s: bad flags: 0x%x", __func__, flags)); 1048 1049 if (flags & M_NOWAIT) { 1050 if (!sx_try_slock(&kld_sx)) 1051 return (EWOULDBLOCK); 1052 } else 1053 sx_slock(&kld_sx); 1054 1055 error = linker_debug_search_symbol_name(value, buf, buflen, offset); 1056 sx_sunlock(&kld_sx); 1057 return (error); 1058 } 1059 1060 int 1061 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1062 long *offset) 1063 { 1064 1065 return (linker_search_symbol_name_flags(value, buf, buflen, offset, 1066 M_WAITOK)); 1067 } 1068 1069 int 1070 linker_kldload_busy(int flags) 1071 { 1072 int error; 1073 1074 MPASS((flags & ~(LINKER_UB_UNLOCK | LINKER_UB_LOCKED | 1075 LINKER_UB_PCATCH)) == 0); 1076 if ((flags & LINKER_UB_LOCKED) != 0) 1077 sx_assert(&kld_sx, SA_XLOCKED); 1078 1079 if ((flags & LINKER_UB_LOCKED) == 0) 1080 sx_xlock(&kld_sx); 1081 while (kld_busy > 0) { 1082 if (kld_busy_owner == curthread) 1083 break; 1084 error = sx_sleep(&kld_busy, &kld_sx, 1085 (flags & LINKER_UB_PCATCH) != 0 ? PCATCH : 0, 1086 "kldbusy", 0); 1087 if (error != 0) { 1088 if ((flags & LINKER_UB_UNLOCK) != 0) 1089 sx_xunlock(&kld_sx); 1090 return (error); 1091 } 1092 } 1093 kld_busy++; 1094 kld_busy_owner = curthread; 1095 if ((flags & LINKER_UB_UNLOCK) != 0) 1096 sx_xunlock(&kld_sx); 1097 return (0); 1098 } 1099 1100 void 1101 linker_kldload_unbusy(int flags) 1102 { 1103 MPASS((flags & ~LINKER_UB_LOCKED) == 0); 1104 if ((flags & LINKER_UB_LOCKED) != 0) 1105 sx_assert(&kld_sx, SA_XLOCKED); 1106 1107 if ((flags & LINKER_UB_LOCKED) == 0) 1108 sx_xlock(&kld_sx); 1109 MPASS(kld_busy > 0); 1110 if (kld_busy_owner != curthread) 1111 panic("linker_kldload_unbusy done by not owning thread %p", 1112 kld_busy_owner); 1113 kld_busy--; 1114 if (kld_busy == 0) { 1115 kld_busy_owner = NULL; 1116 wakeup(&kld_busy); 1117 } 1118 sx_xunlock(&kld_sx); 1119 } 1120 1121 /* 1122 * Syscalls. 1123 */ 1124 int 1125 kern_kldload(struct thread *td, const char *file, int *fileid) 1126 { 1127 const char *kldname, *modname; 1128 linker_file_t lf; 1129 int error; 1130 1131 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1132 return (error); 1133 1134 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 1135 return (error); 1136 1137 /* 1138 * If file does not contain a qualified name or any dot in it 1139 * (kldname.ko, or kldname.ver.ko) treat it as an interface 1140 * name. 1141 */ 1142 if (strchr(file, '/') || strchr(file, '.')) { 1143 kldname = file; 1144 modname = NULL; 1145 } else { 1146 kldname = NULL; 1147 modname = file; 1148 } 1149 1150 error = linker_kldload_busy(LINKER_UB_PCATCH); 1151 if (error != 0) { 1152 sx_xunlock(&kld_sx); 1153 return (error); 1154 } 1155 1156 /* 1157 * It is possible that kldloaded module will attach a new ifnet, 1158 * so vnet context must be set when this ocurs. 1159 */ 1160 CURVNET_SET(TD_TO_VNET(td)); 1161 1162 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 1163 CURVNET_RESTORE(); 1164 1165 if (error == 0) { 1166 lf->userrefs++; 1167 if (fileid != NULL) 1168 *fileid = lf->id; 1169 } 1170 linker_kldload_unbusy(LINKER_UB_LOCKED); 1171 return (error); 1172 } 1173 1174 int 1175 sys_kldload(struct thread *td, struct kldload_args *uap) 1176 { 1177 char *pathname = NULL; 1178 int error, fileid; 1179 1180 td->td_retval[0] = -1; 1181 1182 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1183 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 1184 if (error == 0) { 1185 error = kern_kldload(td, pathname, &fileid); 1186 if (error == 0) 1187 td->td_retval[0] = fileid; 1188 } 1189 free(pathname, M_TEMP); 1190 return (error); 1191 } 1192 1193 int 1194 kern_kldunload(struct thread *td, int fileid, int flags) 1195 { 1196 linker_file_t lf; 1197 int error = 0; 1198 1199 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1200 return (error); 1201 1202 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 1203 return (error); 1204 1205 error = linker_kldload_busy(LINKER_UB_PCATCH); 1206 if (error != 0) { 1207 sx_xunlock(&kld_sx); 1208 return (error); 1209 } 1210 1211 CURVNET_SET(TD_TO_VNET(td)); 1212 lf = linker_find_file_by_id(fileid); 1213 if (lf) { 1214 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 1215 1216 if (lf->userrefs == 0) { 1217 /* 1218 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 1219 */ 1220 printf("kldunload: attempt to unload file that was" 1221 " loaded by the kernel\n"); 1222 error = EBUSY; 1223 } else { 1224 lf->userrefs--; 1225 error = linker_file_unload(lf, flags); 1226 if (error) 1227 lf->userrefs++; 1228 } 1229 } else 1230 error = ENOENT; 1231 CURVNET_RESTORE(); 1232 linker_kldload_unbusy(LINKER_UB_LOCKED); 1233 return (error); 1234 } 1235 1236 int 1237 sys_kldunload(struct thread *td, struct kldunload_args *uap) 1238 { 1239 1240 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 1241 } 1242 1243 int 1244 sys_kldunloadf(struct thread *td, struct kldunloadf_args *uap) 1245 { 1246 1247 if (uap->flags != LINKER_UNLOAD_NORMAL && 1248 uap->flags != LINKER_UNLOAD_FORCE) 1249 return (EINVAL); 1250 return (kern_kldunload(td, uap->fileid, uap->flags)); 1251 } 1252 1253 int 1254 sys_kldfind(struct thread *td, struct kldfind_args *uap) 1255 { 1256 char *pathname; 1257 const char *filename; 1258 linker_file_t lf; 1259 int error; 1260 1261 #ifdef MAC 1262 error = mac_kld_check_stat(td->td_ucred); 1263 if (error) 1264 return (error); 1265 #endif 1266 1267 td->td_retval[0] = -1; 1268 1269 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1270 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1271 goto out; 1272 1273 filename = linker_basename(pathname); 1274 sx_xlock(&kld_sx); 1275 lf = linker_find_file_by_name(filename); 1276 if (lf) 1277 td->td_retval[0] = lf->id; 1278 else 1279 error = ENOENT; 1280 sx_xunlock(&kld_sx); 1281 out: 1282 free(pathname, M_TEMP); 1283 return (error); 1284 } 1285 1286 int 1287 sys_kldnext(struct thread *td, struct kldnext_args *uap) 1288 { 1289 linker_file_t lf; 1290 int error = 0; 1291 1292 #ifdef MAC 1293 error = mac_kld_check_stat(td->td_ucred); 1294 if (error) 1295 return (error); 1296 #endif 1297 1298 sx_xlock(&kld_sx); 1299 if (uap->fileid == 0) 1300 lf = TAILQ_FIRST(&linker_files); 1301 else { 1302 lf = linker_find_file_by_id(uap->fileid); 1303 if (lf == NULL) { 1304 error = ENOENT; 1305 goto out; 1306 } 1307 lf = TAILQ_NEXT(lf, link); 1308 } 1309 1310 /* Skip partially loaded files. */ 1311 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1312 lf = TAILQ_NEXT(lf, link); 1313 1314 if (lf) 1315 td->td_retval[0] = lf->id; 1316 else 1317 td->td_retval[0] = 0; 1318 out: 1319 sx_xunlock(&kld_sx); 1320 return (error); 1321 } 1322 1323 int 1324 sys_kldstat(struct thread *td, struct kldstat_args *uap) 1325 { 1326 struct kld_file_stat *stat; 1327 int error, version; 1328 1329 /* 1330 * Check the version of the user's structure. 1331 */ 1332 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) 1333 != 0) 1334 return (error); 1335 if (version != sizeof(struct kld_file_stat_1) && 1336 version != sizeof(struct kld_file_stat)) 1337 return (EINVAL); 1338 1339 stat = malloc(sizeof(*stat), M_TEMP, M_WAITOK | M_ZERO); 1340 error = kern_kldstat(td, uap->fileid, stat); 1341 if (error == 0) 1342 error = copyout(stat, uap->stat, version); 1343 free(stat, M_TEMP); 1344 return (error); 1345 } 1346 1347 int 1348 kern_kldstat(struct thread *td, int fileid, struct kld_file_stat *stat) 1349 { 1350 linker_file_t lf; 1351 int namelen; 1352 #ifdef MAC 1353 int error; 1354 1355 error = mac_kld_check_stat(td->td_ucred); 1356 if (error) 1357 return (error); 1358 #endif 1359 1360 sx_xlock(&kld_sx); 1361 lf = linker_find_file_by_id(fileid); 1362 if (lf == NULL) { 1363 sx_xunlock(&kld_sx); 1364 return (ENOENT); 1365 } 1366 1367 /* Version 1 fields: */ 1368 namelen = strlen(lf->filename) + 1; 1369 if (namelen > sizeof(stat->name)) 1370 namelen = sizeof(stat->name); 1371 bcopy(lf->filename, &stat->name[0], namelen); 1372 stat->refs = lf->refs; 1373 stat->id = lf->id; 1374 stat->address = lf->address; 1375 stat->size = lf->size; 1376 /* Version 2 fields: */ 1377 namelen = strlen(lf->pathname) + 1; 1378 if (namelen > sizeof(stat->pathname)) 1379 namelen = sizeof(stat->pathname); 1380 bcopy(lf->pathname, &stat->pathname[0], namelen); 1381 sx_xunlock(&kld_sx); 1382 1383 td->td_retval[0] = 0; 1384 return (0); 1385 } 1386 1387 #ifdef DDB 1388 DB_COMMAND_FLAGS(kldstat, db_kldstat, DB_CMD_MEMSAFE) 1389 { 1390 linker_file_t lf; 1391 1392 #define POINTER_WIDTH ((int)(sizeof(void *) * 2 + 2)) 1393 db_printf("Id Refs Address%*c Size Name\n", POINTER_WIDTH - 7, ' '); 1394 #undef POINTER_WIDTH 1395 TAILQ_FOREACH(lf, &linker_files, link) { 1396 if (db_pager_quit) 1397 return; 1398 db_printf("%2d %4d %p %-8zx %s\n", lf->id, lf->refs, 1399 lf->address, lf->size, lf->filename); 1400 } 1401 } 1402 #endif /* DDB */ 1403 1404 int 1405 sys_kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1406 { 1407 linker_file_t lf; 1408 module_t mp; 1409 int error = 0; 1410 1411 #ifdef MAC 1412 error = mac_kld_check_stat(td->td_ucred); 1413 if (error) 1414 return (error); 1415 #endif 1416 1417 sx_xlock(&kld_sx); 1418 lf = linker_find_file_by_id(uap->fileid); 1419 if (lf) { 1420 MOD_SLOCK; 1421 mp = TAILQ_FIRST(&lf->modules); 1422 if (mp != NULL) 1423 td->td_retval[0] = module_getid(mp); 1424 else 1425 td->td_retval[0] = 0; 1426 MOD_SUNLOCK; 1427 } else 1428 error = ENOENT; 1429 sx_xunlock(&kld_sx); 1430 return (error); 1431 } 1432 1433 int 1434 sys_kldsym(struct thread *td, struct kldsym_args *uap) 1435 { 1436 char *symstr = NULL; 1437 c_linker_sym_t sym; 1438 linker_symval_t symval; 1439 linker_file_t lf; 1440 struct kld_sym_lookup lookup; 1441 int error = 0; 1442 1443 #ifdef MAC 1444 error = mac_kld_check_stat(td->td_ucred); 1445 if (error) 1446 return (error); 1447 #endif 1448 1449 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1450 return (error); 1451 if (lookup.version != sizeof(lookup) || 1452 uap->cmd != KLDSYM_LOOKUP) 1453 return (EINVAL); 1454 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1455 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1456 goto out; 1457 sx_xlock(&kld_sx); 1458 if (uap->fileid != 0) { 1459 lf = linker_find_file_by_id(uap->fileid); 1460 if (lf == NULL) 1461 error = ENOENT; 1462 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1463 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1464 lookup.symvalue = (uintptr_t) symval.value; 1465 lookup.symsize = symval.size; 1466 error = copyout(&lookup, uap->data, sizeof(lookup)); 1467 } else 1468 error = ENOENT; 1469 } else { 1470 TAILQ_FOREACH(lf, &linker_files, link) { 1471 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1472 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1473 lookup.symvalue = (uintptr_t)symval.value; 1474 lookup.symsize = symval.size; 1475 error = copyout(&lookup, uap->data, 1476 sizeof(lookup)); 1477 break; 1478 } 1479 } 1480 if (lf == NULL) 1481 error = ENOENT; 1482 } 1483 sx_xunlock(&kld_sx); 1484 out: 1485 free(symstr, M_TEMP); 1486 return (error); 1487 } 1488 1489 /* 1490 * Preloaded module support 1491 */ 1492 1493 static modlist_t 1494 modlist_lookup(const char *name, int ver) 1495 { 1496 modlist_t mod; 1497 1498 TAILQ_FOREACH(mod, &found_modules, link) { 1499 if (strcmp(mod->name, name) == 0 && 1500 (ver == 0 || mod->version == ver)) 1501 return (mod); 1502 } 1503 return (NULL); 1504 } 1505 1506 static modlist_t 1507 modlist_lookup2(const char *name, const struct mod_depend *verinfo) 1508 { 1509 modlist_t mod, bestmod; 1510 int ver; 1511 1512 if (verinfo == NULL) 1513 return (modlist_lookup(name, 0)); 1514 bestmod = NULL; 1515 TAILQ_FOREACH(mod, &found_modules, link) { 1516 if (strcmp(mod->name, name) != 0) 1517 continue; 1518 ver = mod->version; 1519 if (ver == verinfo->md_ver_preferred) 1520 return (mod); 1521 if (ver >= verinfo->md_ver_minimum && 1522 ver <= verinfo->md_ver_maximum && 1523 (bestmod == NULL || ver > bestmod->version)) 1524 bestmod = mod; 1525 } 1526 return (bestmod); 1527 } 1528 1529 static modlist_t 1530 modlist_newmodule(const char *modname, int version, linker_file_t container) 1531 { 1532 modlist_t mod; 1533 1534 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1535 if (mod == NULL) 1536 panic("no memory for module list"); 1537 mod->container = container; 1538 mod->name = modname; 1539 mod->version = version; 1540 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1541 return (mod); 1542 } 1543 1544 static void 1545 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1546 struct mod_metadata **stop, int preload) 1547 { 1548 struct mod_metadata *mp, **mdp; 1549 const char *modname; 1550 int ver; 1551 1552 for (mdp = start; mdp < stop; mdp++) { 1553 mp = *mdp; 1554 if (mp->md_type != MDT_VERSION) 1555 continue; 1556 modname = mp->md_cval; 1557 ver = ((const struct mod_version *)mp->md_data)->mv_version; 1558 if (modlist_lookup(modname, ver) != NULL) { 1559 printf("module %s already present!\n", modname); 1560 /* XXX what can we do? this is a build error. :-( */ 1561 continue; 1562 } 1563 modlist_newmodule(modname, ver, lf); 1564 } 1565 } 1566 1567 static void 1568 linker_preload(void *arg) 1569 { 1570 caddr_t modptr; 1571 const char *modname, *nmodname; 1572 char *modtype; 1573 linker_file_t lf, nlf; 1574 linker_class_t lc; 1575 int error; 1576 linker_file_list_t loaded_files; 1577 linker_file_list_t depended_files; 1578 struct mod_metadata *mp, *nmp; 1579 struct mod_metadata **start, **stop, **mdp, **nmdp; 1580 const struct mod_depend *verinfo; 1581 int nver; 1582 int resolves; 1583 modlist_t mod; 1584 struct sysinit **si_start, **si_stop; 1585 1586 TAILQ_INIT(&loaded_files); 1587 TAILQ_INIT(&depended_files); 1588 TAILQ_INIT(&found_modules); 1589 error = 0; 1590 1591 modptr = NULL; 1592 sx_xlock(&kld_sx); 1593 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1594 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1595 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1596 if (modname == NULL) { 1597 printf("Preloaded module at %p does not have a" 1598 " name!\n", modptr); 1599 continue; 1600 } 1601 if (modtype == NULL) { 1602 printf("Preloaded module at %p does not have a type!\n", 1603 modptr); 1604 continue; 1605 } 1606 if (bootverbose) 1607 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1608 modptr); 1609 lf = NULL; 1610 TAILQ_FOREACH(lc, &classes, link) { 1611 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1612 if (!error) 1613 break; 1614 lf = NULL; 1615 } 1616 if (lf) 1617 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1618 } 1619 1620 /* 1621 * First get a list of stuff in the kernel. 1622 */ 1623 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1624 &stop, NULL) == 0) 1625 linker_addmodules(linker_kernel_file, start, stop, 1); 1626 1627 /* 1628 * This is a once-off kinky bubble sort to resolve relocation 1629 * dependency requirements. 1630 */ 1631 restart: 1632 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1633 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1634 &stop, NULL); 1635 /* 1636 * First, look to see if we would successfully link with this 1637 * stuff. 1638 */ 1639 resolves = 1; /* unless we know otherwise */ 1640 if (!error) { 1641 for (mdp = start; mdp < stop; mdp++) { 1642 mp = *mdp; 1643 if (mp->md_type != MDT_DEPEND) 1644 continue; 1645 modname = mp->md_cval; 1646 verinfo = mp->md_data; 1647 for (nmdp = start; nmdp < stop; nmdp++) { 1648 nmp = *nmdp; 1649 if (nmp->md_type != MDT_VERSION) 1650 continue; 1651 nmodname = nmp->md_cval; 1652 if (strcmp(modname, nmodname) == 0) 1653 break; 1654 } 1655 if (nmdp < stop) /* it's a self reference */ 1656 continue; 1657 1658 /* 1659 * ok, the module isn't here yet, we 1660 * are not finished 1661 */ 1662 if (modlist_lookup2(modname, verinfo) == NULL) 1663 resolves = 0; 1664 } 1665 } 1666 /* 1667 * OK, if we found our modules, we can link. So, "provide" 1668 * the modules inside and add it to the end of the link order 1669 * list. 1670 */ 1671 if (resolves) { 1672 if (!error) { 1673 for (mdp = start; mdp < stop; mdp++) { 1674 mp = *mdp; 1675 if (mp->md_type != MDT_VERSION) 1676 continue; 1677 modname = mp->md_cval; 1678 nver = ((const struct mod_version *) 1679 mp->md_data)->mv_version; 1680 if (modlist_lookup(modname, 1681 nver) != NULL) { 1682 printf("module %s already" 1683 " present!\n", modname); 1684 TAILQ_REMOVE(&loaded_files, 1685 lf, loaded); 1686 linker_file_unload(lf, 1687 LINKER_UNLOAD_FORCE); 1688 /* we changed tailq next ptr */ 1689 goto restart; 1690 } 1691 modlist_newmodule(modname, nver, lf); 1692 } 1693 } 1694 TAILQ_REMOVE(&loaded_files, lf, loaded); 1695 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1696 /* 1697 * Since we provided modules, we need to restart the 1698 * sort so that the previous files that depend on us 1699 * have a chance. Also, we've busted the tailq next 1700 * pointer with the REMOVE. 1701 */ 1702 goto restart; 1703 } 1704 } 1705 1706 /* 1707 * At this point, we check to see what could not be resolved.. 1708 */ 1709 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1710 TAILQ_REMOVE(&loaded_files, lf, loaded); 1711 printf("KLD file %s is missing dependencies\n", lf->filename); 1712 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1713 } 1714 1715 /* 1716 * We made it. Finish off the linking in the order we determined. 1717 */ 1718 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1719 if (linker_kernel_file) { 1720 linker_kernel_file->refs++; 1721 error = linker_file_add_dependency(lf, 1722 linker_kernel_file); 1723 if (error) 1724 panic("cannot add dependency"); 1725 } 1726 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1727 &stop, NULL); 1728 if (!error) { 1729 for (mdp = start; mdp < stop; mdp++) { 1730 mp = *mdp; 1731 if (mp->md_type != MDT_DEPEND) 1732 continue; 1733 modname = mp->md_cval; 1734 verinfo = mp->md_data; 1735 mod = modlist_lookup2(modname, verinfo); 1736 if (mod == NULL) { 1737 printf("KLD file %s - cannot find " 1738 "dependency \"%s\"\n", 1739 lf->filename, modname); 1740 goto fail; 1741 } 1742 /* Don't count self-dependencies */ 1743 if (lf == mod->container) 1744 continue; 1745 mod->container->refs++; 1746 error = linker_file_add_dependency(lf, 1747 mod->container); 1748 if (error) 1749 panic("cannot add dependency"); 1750 } 1751 } 1752 /* 1753 * Now do relocation etc using the symbol search paths 1754 * established by the dependencies 1755 */ 1756 error = LINKER_LINK_PRELOAD_FINISH(lf); 1757 if (error) { 1758 printf("KLD file %s - could not finalize loading\n", 1759 lf->filename); 1760 goto fail; 1761 } 1762 linker_file_register_modules(lf); 1763 if (!TAILQ_EMPTY(&lf->modules)) 1764 lf->flags |= LINKER_FILE_MODULES; 1765 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1766 &si_stop, NULL) == 0) 1767 sysinit_add(si_start, si_stop); 1768 linker_file_register_sysctls(lf, true); 1769 lf->flags |= LINKER_FILE_LINKED; 1770 continue; 1771 fail: 1772 TAILQ_REMOVE(&depended_files, lf, loaded); 1773 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1774 } 1775 sx_xunlock(&kld_sx); 1776 /* woohoo! we made it! */ 1777 } 1778 1779 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, NULL); 1780 1781 /* 1782 * Handle preload files that failed to load any modules. 1783 */ 1784 static void 1785 linker_preload_finish(void *arg) 1786 { 1787 linker_file_t lf, nlf; 1788 1789 sx_xlock(&kld_sx); 1790 TAILQ_FOREACH_SAFE(lf, &linker_files, link, nlf) { 1791 /* 1792 * If all of the modules in this file failed to load, unload 1793 * the file and return an error of ENOEXEC. (Parity with 1794 * linker_load_file.) 1795 */ 1796 if ((lf->flags & LINKER_FILE_MODULES) != 0 && 1797 TAILQ_EMPTY(&lf->modules)) { 1798 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1799 continue; 1800 } 1801 1802 lf->flags &= ~LINKER_FILE_MODULES; 1803 lf->userrefs++; /* so we can (try to) kldunload it */ 1804 } 1805 sx_xunlock(&kld_sx); 1806 } 1807 1808 /* 1809 * Attempt to run after all DECLARE_MODULE SYSINITs. Unfortunately they can be 1810 * scheduled at any subsystem and order, so run this as late as possible. init 1811 * becomes runnable in SI_SUB_KTHREAD_INIT, so go slightly before that. 1812 */ 1813 SYSINIT(preload_finish, SI_SUB_KTHREAD_INIT - 100, SI_ORDER_MIDDLE, 1814 linker_preload_finish, NULL); 1815 1816 /* 1817 * Search for a not-loaded module by name. 1818 * 1819 * Modules may be found in the following locations: 1820 * 1821 * - preloaded (result is just the module name) - on disk (result is full path 1822 * to module) 1823 * 1824 * If the module name is qualified in any way (contains path, etc.) the we 1825 * simply return a copy of it. 1826 * 1827 * The search path can be manipulated via sysctl. Note that we use the ';' 1828 * character as a separator to be consistent with the bootloader. 1829 */ 1830 1831 static char linker_hintfile[] = "linker.hints"; 1832 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1833 1834 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RWTUN, linker_path, 1835 sizeof(linker_path), "module load search path"); 1836 1837 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1838 1839 static const char * const linker_ext_list[] = { 1840 "", 1841 ".ko", 1842 NULL 1843 }; 1844 1845 /* 1846 * Check if file actually exists either with or without extension listed in 1847 * the linker_ext_list. (probably should be generic for the rest of the 1848 * kernel) 1849 */ 1850 static char * 1851 linker_lookup_file(const char *path, int pathlen, const char *name, 1852 int namelen, struct vattr *vap) 1853 { 1854 struct nameidata nd; 1855 struct thread *td = curthread; /* XXX */ 1856 const char * const *cpp, *sep; 1857 char *result; 1858 int error, len, extlen, reclen, flags; 1859 __enum_uint8(vtype) type; 1860 1861 extlen = 0; 1862 for (cpp = linker_ext_list; *cpp; cpp++) { 1863 len = strlen(*cpp); 1864 if (len > extlen) 1865 extlen = len; 1866 } 1867 extlen++; /* trailing '\0' */ 1868 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1869 1870 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1871 result = malloc(reclen, M_LINKER, M_WAITOK); 1872 for (cpp = linker_ext_list; *cpp; cpp++) { 1873 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1874 namelen, name, *cpp); 1875 /* 1876 * Attempt to open the file, and return the path if 1877 * we succeed and it's a regular file. 1878 */ 1879 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result); 1880 flags = FREAD; 1881 error = vn_open(&nd, &flags, 0, NULL); 1882 if (error == 0) { 1883 NDFREE_PNBUF(&nd); 1884 type = nd.ni_vp->v_type; 1885 if (vap) 1886 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred); 1887 VOP_UNLOCK(nd.ni_vp); 1888 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1889 if (type == VREG) 1890 return (result); 1891 } 1892 } 1893 free(result, M_LINKER); 1894 return (NULL); 1895 } 1896 1897 #define INT_ALIGN(base, ptr) ptr = \ 1898 (base) + roundup2((ptr) - (base), sizeof(int)) 1899 1900 /* 1901 * Lookup KLD which contains requested module in the "linker.hints" file. If 1902 * version specification is available, then try to find the best KLD. 1903 * Otherwise just find the latest one. 1904 */ 1905 static char * 1906 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1907 int modnamelen, const struct mod_depend *verinfo) 1908 { 1909 struct thread *td = curthread; /* XXX */ 1910 struct ucred *cred = td ? td->td_ucred : NULL; 1911 struct nameidata nd; 1912 struct vattr vattr, mattr; 1913 const char *best, *sep; 1914 u_char *hints = NULL; 1915 u_char *cp, *recptr, *bufend, *result, *pathbuf; 1916 int error, ival, bestver, *intp, found, flags, clen, blen; 1917 ssize_t reclen; 1918 1919 result = NULL; 1920 bestver = found = 0; 1921 1922 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1923 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1924 strlen(sep) + 1; 1925 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1926 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1927 linker_hintfile); 1928 1929 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf); 1930 flags = FREAD; 1931 error = vn_open(&nd, &flags, 0, NULL); 1932 if (error) 1933 goto bad; 1934 NDFREE_PNBUF(&nd); 1935 if (nd.ni_vp->v_type != VREG) 1936 goto bad; 1937 best = cp = NULL; 1938 error = VOP_GETATTR(nd.ni_vp, &vattr, cred); 1939 if (error) 1940 goto bad; 1941 /* 1942 * XXX: we need to limit this number to some reasonable value 1943 */ 1944 if (vattr.va_size > LINKER_HINTS_MAX) { 1945 printf("linker.hints file too large %ld\n", (long)vattr.va_size); 1946 goto bad; 1947 } 1948 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1949 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1950 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1951 if (error) 1952 goto bad; 1953 VOP_UNLOCK(nd.ni_vp); 1954 vn_close(nd.ni_vp, FREAD, cred, td); 1955 nd.ni_vp = NULL; 1956 if (reclen != 0) { 1957 printf("can't read %zd\n", reclen); 1958 goto bad; 1959 } 1960 intp = (int *)hints; 1961 ival = *intp++; 1962 if (ival != LINKER_HINTS_VERSION) { 1963 printf("linker.hints file version mismatch %d\n", ival); 1964 goto bad; 1965 } 1966 bufend = hints + vattr.va_size; 1967 recptr = (u_char *)intp; 1968 clen = blen = 0; 1969 while (recptr < bufend && !found) { 1970 intp = (int *)recptr; 1971 reclen = *intp++; 1972 ival = *intp++; 1973 cp = (char *)intp; 1974 switch (ival) { 1975 case MDT_VERSION: 1976 clen = *cp++; 1977 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1978 break; 1979 cp += clen; 1980 INT_ALIGN(hints, cp); 1981 ival = *(int *)cp; 1982 cp += sizeof(int); 1983 clen = *cp++; 1984 if (verinfo == NULL || 1985 ival == verinfo->md_ver_preferred) { 1986 found = 1; 1987 break; 1988 } 1989 if (ival >= verinfo->md_ver_minimum && 1990 ival <= verinfo->md_ver_maximum && 1991 ival > bestver) { 1992 bestver = ival; 1993 best = cp; 1994 blen = clen; 1995 } 1996 break; 1997 default: 1998 break; 1999 } 2000 recptr += reclen + sizeof(int); 2001 } 2002 /* 2003 * Finally check if KLD is in the place 2004 */ 2005 if (found) 2006 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 2007 else if (best) 2008 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 2009 2010 /* 2011 * KLD is newer than hints file. What we should do now? 2012 */ 2013 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 2014 printf("warning: KLD '%s' is newer than the linker.hints" 2015 " file\n", result); 2016 bad: 2017 free(pathbuf, M_LINKER); 2018 if (hints) 2019 free(hints, M_TEMP); 2020 if (nd.ni_vp != NULL) { 2021 VOP_UNLOCK(nd.ni_vp); 2022 vn_close(nd.ni_vp, FREAD, cred, td); 2023 } 2024 /* 2025 * If nothing found or hints is absent - fallback to the old 2026 * way by using "kldname[.ko]" as module name. 2027 */ 2028 if (!found && !bestver && result == NULL) 2029 result = linker_lookup_file(path, pathlen, modname, 2030 modnamelen, NULL); 2031 return (result); 2032 } 2033 2034 /* 2035 * Lookup KLD which contains requested module in the all directories. 2036 */ 2037 static char * 2038 linker_search_module(const char *modname, int modnamelen, 2039 const struct mod_depend *verinfo) 2040 { 2041 char *cp, *ep, *result; 2042 2043 /* 2044 * traverse the linker path 2045 */ 2046 for (cp = linker_path; *cp; cp = ep + 1) { 2047 /* find the end of this component */ 2048 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 2049 result = linker_hints_lookup(cp, ep - cp, modname, 2050 modnamelen, verinfo); 2051 if (result != NULL) 2052 return (result); 2053 if (*ep == 0) 2054 break; 2055 } 2056 return (NULL); 2057 } 2058 2059 /* 2060 * Search for module in all directories listed in the linker_path. 2061 */ 2062 static char * 2063 linker_search_kld(const char *name) 2064 { 2065 char *cp, *ep, *result; 2066 int len; 2067 2068 /* qualified at all? */ 2069 if (strchr(name, '/')) 2070 return (strdup(name, M_LINKER)); 2071 2072 /* traverse the linker path */ 2073 len = strlen(name); 2074 for (ep = linker_path; *ep; ep++) { 2075 cp = ep; 2076 /* find the end of this component */ 2077 for (; *ep != 0 && *ep != ';'; ep++); 2078 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 2079 if (result != NULL) 2080 return (result); 2081 } 2082 return (NULL); 2083 } 2084 2085 static const char * 2086 linker_basename(const char *path) 2087 { 2088 const char *filename; 2089 2090 filename = strrchr(path, '/'); 2091 if (filename == NULL) 2092 return path; 2093 if (filename[1]) 2094 filename++; 2095 return (filename); 2096 } 2097 2098 #ifdef HWPMC_HOOKS 2099 /* 2100 * Inform hwpmc about the set of kernel modules currently loaded. 2101 */ 2102 void * 2103 linker_hwpmc_list_objects(void) 2104 { 2105 linker_file_t lf; 2106 struct pmckern_map_in *kobase; 2107 int i, nmappings; 2108 2109 nmappings = 0; 2110 sx_slock(&kld_sx); 2111 TAILQ_FOREACH(lf, &linker_files, link) 2112 nmappings++; 2113 2114 /* Allocate nmappings + 1 entries. */ 2115 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in), 2116 M_LINKER, M_WAITOK | M_ZERO); 2117 i = 0; 2118 TAILQ_FOREACH(lf, &linker_files, link) { 2119 /* Save the info for this linker file. */ 2120 kobase[i].pm_file = lf->pathname; 2121 kobase[i].pm_address = (uintptr_t)lf->address; 2122 i++; 2123 } 2124 sx_sunlock(&kld_sx); 2125 2126 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?")); 2127 2128 /* The last entry of the malloced area comprises of all zeros. */ 2129 KASSERT(kobase[i].pm_file == NULL, 2130 ("linker_hwpmc_list_objects: last object not NULL")); 2131 2132 return ((void *)kobase); 2133 } 2134 #endif 2135 2136 /* check if root file system is not mounted */ 2137 static bool 2138 linker_root_mounted(void) 2139 { 2140 struct pwd *pwd; 2141 bool ret; 2142 2143 if (rootvnode == NULL) 2144 return (false); 2145 2146 pwd = pwd_hold(curthread); 2147 ret = pwd->pwd_rdir != NULL; 2148 pwd_drop(pwd); 2149 return (ret); 2150 } 2151 2152 /* 2153 * Find a file which contains given module and load it, if "parent" is not 2154 * NULL, register a reference to it. 2155 */ 2156 static int 2157 linker_load_module(const char *kldname, const char *modname, 2158 struct linker_file *parent, const struct mod_depend *verinfo, 2159 struct linker_file **lfpp) 2160 { 2161 linker_file_t lfdep; 2162 const char *filename; 2163 char *pathname; 2164 int error; 2165 2166 sx_assert(&kld_sx, SA_XLOCKED); 2167 if (modname == NULL) { 2168 /* 2169 * We have to load KLD 2170 */ 2171 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 2172 " is not NULL")); 2173 if (!linker_root_mounted()) 2174 return (ENXIO); 2175 pathname = linker_search_kld(kldname); 2176 } else { 2177 if (modlist_lookup2(modname, verinfo) != NULL) 2178 return (EEXIST); 2179 if (!linker_root_mounted()) 2180 return (ENXIO); 2181 if (kldname != NULL) 2182 pathname = strdup(kldname, M_LINKER); 2183 else 2184 /* 2185 * Need to find a KLD with required module 2186 */ 2187 pathname = linker_search_module(modname, 2188 strlen(modname), verinfo); 2189 } 2190 if (pathname == NULL) 2191 return (ENOENT); 2192 2193 /* 2194 * Can't load more than one file with the same basename XXX: 2195 * Actually it should be possible to have multiple KLDs with 2196 * the same basename but different path because they can 2197 * provide different versions of the same modules. 2198 */ 2199 filename = linker_basename(pathname); 2200 if (linker_find_file_by_name(filename)) 2201 error = EEXIST; 2202 else do { 2203 error = linker_load_file(pathname, &lfdep); 2204 if (error) 2205 break; 2206 if (modname && verinfo && 2207 modlist_lookup2(modname, verinfo) == NULL) { 2208 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 2209 error = ENOENT; 2210 break; 2211 } 2212 if (parent) { 2213 error = linker_file_add_dependency(parent, lfdep); 2214 if (error) 2215 break; 2216 } 2217 if (lfpp) 2218 *lfpp = lfdep; 2219 } while (0); 2220 free(pathname, M_LINKER); 2221 return (error); 2222 } 2223 2224 /* 2225 * This routine is responsible for finding dependencies of userland initiated 2226 * kldload(2)'s of files. 2227 */ 2228 int 2229 linker_load_dependencies(linker_file_t lf) 2230 { 2231 linker_file_t lfdep; 2232 struct mod_metadata **start, **stop, **mdp, **nmdp; 2233 struct mod_metadata *mp, *nmp; 2234 const struct mod_depend *verinfo; 2235 modlist_t mod; 2236 const char *modname, *nmodname; 2237 int ver, error = 0; 2238 2239 /* 2240 * All files are dependent on /kernel. 2241 */ 2242 sx_assert(&kld_sx, SA_XLOCKED); 2243 if (linker_kernel_file) { 2244 linker_kernel_file->refs++; 2245 error = linker_file_add_dependency(lf, linker_kernel_file); 2246 if (error) 2247 return (error); 2248 } 2249 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 2250 NULL) != 0) 2251 return (0); 2252 for (mdp = start; mdp < stop; mdp++) { 2253 mp = *mdp; 2254 if (mp->md_type != MDT_VERSION) 2255 continue; 2256 modname = mp->md_cval; 2257 ver = ((const struct mod_version *)mp->md_data)->mv_version; 2258 mod = modlist_lookup(modname, ver); 2259 if (mod != NULL) { 2260 printf("interface %s.%d already present in the KLD" 2261 " '%s'!\n", modname, ver, 2262 mod->container->filename); 2263 return (EEXIST); 2264 } 2265 } 2266 2267 for (mdp = start; mdp < stop; mdp++) { 2268 mp = *mdp; 2269 if (mp->md_type != MDT_DEPEND) 2270 continue; 2271 modname = mp->md_cval; 2272 verinfo = mp->md_data; 2273 nmodname = NULL; 2274 for (nmdp = start; nmdp < stop; nmdp++) { 2275 nmp = *nmdp; 2276 if (nmp->md_type != MDT_VERSION) 2277 continue; 2278 nmodname = nmp->md_cval; 2279 if (strcmp(modname, nmodname) == 0) 2280 break; 2281 } 2282 if (nmdp < stop)/* early exit, it's a self reference */ 2283 continue; 2284 mod = modlist_lookup2(modname, verinfo); 2285 if (mod) { /* woohoo, it's loaded already */ 2286 lfdep = mod->container; 2287 lfdep->refs++; 2288 error = linker_file_add_dependency(lf, lfdep); 2289 if (error) 2290 break; 2291 continue; 2292 } 2293 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 2294 if (error) { 2295 printf("KLD %s: depends on %s - not available or" 2296 " version mismatch\n", lf->filename, modname); 2297 break; 2298 } 2299 } 2300 2301 if (error) 2302 return (error); 2303 linker_addmodules(lf, start, stop, 0); 2304 return (error); 2305 } 2306 2307 static int 2308 sysctl_kern_function_list_iterate(const char *name, void *opaque) 2309 { 2310 struct sysctl_req *req; 2311 2312 req = opaque; 2313 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 2314 } 2315 2316 /* 2317 * Export a nul-separated, double-nul-terminated list of all function names 2318 * in the kernel. 2319 */ 2320 static int 2321 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 2322 { 2323 linker_file_t lf; 2324 int error; 2325 2326 #ifdef MAC 2327 error = mac_kld_check_stat(req->td->td_ucred); 2328 if (error) 2329 return (error); 2330 #endif 2331 error = sysctl_wire_old_buffer(req, 0); 2332 if (error != 0) 2333 return (error); 2334 sx_xlock(&kld_sx); 2335 TAILQ_FOREACH(lf, &linker_files, link) { 2336 error = LINKER_EACH_FUNCTION_NAME(lf, 2337 sysctl_kern_function_list_iterate, req); 2338 if (error) { 2339 sx_xunlock(&kld_sx); 2340 return (error); 2341 } 2342 } 2343 sx_xunlock(&kld_sx); 2344 return (SYSCTL_OUT(req, "", 1)); 2345 } 2346 2347 SYSCTL_PROC(_kern, OID_AUTO, function_list, 2348 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 2349 sysctl_kern_function_list, "", 2350 "kernel function list"); 2351