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 #ifdef VIMAGE 475 LINKER_PROPAGATE_VNETS(lf); 476 #endif 477 linker_file_sysinit(lf); 478 lf->flags |= LINKER_FILE_LINKED; 479 480 /* 481 * If all of the modules in this file failed 482 * to load, unload the file and return an 483 * error of ENOEXEC. 484 */ 485 if (modules && TAILQ_EMPTY(&lf->modules)) { 486 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 487 return (ENOEXEC); 488 } 489 linker_file_enable_sysctls(lf); 490 EVENTHANDLER_INVOKE(kld_load, lf); 491 *result = lf; 492 return (0); 493 } 494 } 495 /* 496 * Less than ideal, but tells the user whether it failed to load or 497 * the module was not found. 498 */ 499 if (foundfile) { 500 /* 501 * If the file type has not been recognized by the last try 502 * printout a message before to fail. 503 */ 504 if (error == ENOSYS) 505 printf("%s: %s - unsupported file type\n", 506 __func__, filename); 507 508 /* 509 * Format not recognized or otherwise unloadable. 510 * When loading a module that is statically built into 511 * the kernel EEXIST percolates back up as the return 512 * value. Preserve this so that apps like sysinstall 513 * can recognize this special case and not post bogus 514 * dialog boxes. 515 */ 516 if (error != EEXIST) 517 error = ENOEXEC; 518 } else 519 error = ENOENT; /* Nothing found */ 520 return (error); 521 } 522 523 int 524 linker_reference_module(const char *modname, struct mod_depend *verinfo, 525 linker_file_t *result) 526 { 527 modlist_t mod; 528 int error; 529 530 sx_xlock(&kld_sx); 531 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 532 *result = mod->container; 533 (*result)->refs++; 534 sx_xunlock(&kld_sx); 535 return (0); 536 } 537 538 error = linker_load_module(NULL, modname, NULL, verinfo, result); 539 sx_xunlock(&kld_sx); 540 return (error); 541 } 542 543 int 544 linker_release_module(const char *modname, struct mod_depend *verinfo, 545 linker_file_t lf) 546 { 547 modlist_t mod; 548 int error; 549 550 sx_xlock(&kld_sx); 551 if (lf == NULL) { 552 KASSERT(modname != NULL, 553 ("linker_release_module: no file or name")); 554 mod = modlist_lookup2(modname, verinfo); 555 if (mod == NULL) { 556 sx_xunlock(&kld_sx); 557 return (ESRCH); 558 } 559 lf = mod->container; 560 } else 561 KASSERT(modname == NULL && verinfo == NULL, 562 ("linker_release_module: both file and name")); 563 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL); 564 sx_xunlock(&kld_sx); 565 return (error); 566 } 567 568 static linker_file_t 569 linker_find_file_by_name(const char *filename) 570 { 571 linker_file_t lf; 572 char *koname; 573 574 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 575 sprintf(koname, "%s.ko", filename); 576 577 sx_assert(&kld_sx, SA_XLOCKED); 578 TAILQ_FOREACH(lf, &linker_files, link) { 579 if (strcmp(lf->filename, koname) == 0) 580 break; 581 if (strcmp(lf->filename, filename) == 0) 582 break; 583 } 584 free(koname, M_LINKER); 585 return (lf); 586 } 587 588 static linker_file_t 589 linker_find_file_by_id(int fileid) 590 { 591 linker_file_t lf; 592 593 sx_assert(&kld_sx, SA_XLOCKED); 594 TAILQ_FOREACH(lf, &linker_files, link) 595 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED) 596 break; 597 return (lf); 598 } 599 600 int 601 linker_file_foreach(linker_predicate_t *predicate, void *context) 602 { 603 linker_file_t lf; 604 int retval = 0; 605 606 sx_xlock(&kld_sx); 607 TAILQ_FOREACH(lf, &linker_files, link) { 608 retval = predicate(lf, context); 609 if (retval != 0) 610 break; 611 } 612 sx_xunlock(&kld_sx); 613 return (retval); 614 } 615 616 linker_file_t 617 linker_make_file(const char *pathname, linker_class_t lc) 618 { 619 linker_file_t lf; 620 const char *filename; 621 622 if (!cold) 623 sx_assert(&kld_sx, SA_XLOCKED); 624 filename = linker_basename(pathname); 625 626 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname)); 627 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 628 if (lf == NULL) 629 return (NULL); 630 lf->ctors_addr = 0; 631 lf->ctors_size = 0; 632 lf->dtors_addr = 0; 633 lf->dtors_size = 0; 634 lf->refs = 1; 635 lf->userrefs = 0; 636 lf->flags = 0; 637 lf->filename = strdup(filename, M_LINKER); 638 lf->pathname = strdup(pathname, M_LINKER); 639 LINKER_GET_NEXT_FILE_ID(lf->id); 640 lf->ndeps = 0; 641 lf->deps = NULL; 642 lf->loadcnt = ++loadcnt; 643 #ifdef __arm__ 644 lf->exidx_addr = 0; 645 lf->exidx_size = 0; 646 #endif 647 STAILQ_INIT(&lf->common); 648 TAILQ_INIT(&lf->modules); 649 TAILQ_INSERT_TAIL(&linker_files, lf, link); 650 return (lf); 651 } 652 653 int 654 linker_file_unload(linker_file_t file, int flags) 655 { 656 module_t mod, next; 657 modlist_t ml, nextml; 658 struct common_symbol *cp; 659 int error, i; 660 661 /* Refuse to unload modules if securelevel raised. */ 662 if (prison0.pr_securelevel > 0) 663 return (EPERM); 664 665 sx_assert(&kld_sx, SA_XLOCKED); 666 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 667 668 /* Easy case of just dropping a reference. */ 669 if (file->refs > 1) { 670 file->refs--; 671 return (0); 672 } 673 674 /* Give eventhandlers a chance to prevent the unload. */ 675 error = 0; 676 EVENTHANDLER_INVOKE(kld_unload_try, file, &error); 677 if (error != 0) 678 return (EBUSY); 679 680 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 681 " informing modules\n")); 682 683 /* 684 * Quiesce all the modules to give them a chance to veto the unload. 685 */ 686 MOD_SLOCK; 687 for (mod = TAILQ_FIRST(&file->modules); mod; 688 mod = module_getfnext(mod)) { 689 error = module_quiesce(mod); 690 if (error != 0 && flags != LINKER_UNLOAD_FORCE) { 691 KLD_DPF(FILE, ("linker_file_unload: module %s" 692 " vetoed unload\n", module_getname(mod))); 693 /* 694 * XXX: Do we need to tell all the quiesced modules 695 * that they can resume work now via a new module 696 * event? 697 */ 698 MOD_SUNLOCK; 699 return (error); 700 } 701 } 702 MOD_SUNLOCK; 703 704 /* 705 * Inform any modules associated with this file that they are 706 * being unloaded. 707 */ 708 MOD_XLOCK; 709 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 710 next = module_getfnext(mod); 711 MOD_XUNLOCK; 712 713 /* 714 * Give the module a chance to veto the unload. 715 */ 716 if ((error = module_unload(mod)) != 0) { 717 #ifdef KLD_DEBUG 718 MOD_SLOCK; 719 KLD_DPF(FILE, ("linker_file_unload: module %s" 720 " failed unload\n", module_getname(mod))); 721 MOD_SUNLOCK; 722 #endif 723 return (error); 724 } 725 MOD_XLOCK; 726 module_release(mod); 727 } 728 MOD_XUNLOCK; 729 730 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 731 if (ml->container == file) { 732 TAILQ_REMOVE(&found_modules, ml, link); 733 free(ml, M_LINKER); 734 } 735 } 736 737 /* 738 * Don't try to run SYSUNINITs if we are unloaded due to a 739 * link error. 740 */ 741 if (file->flags & LINKER_FILE_LINKED) { 742 file->flags &= ~LINKER_FILE_LINKED; 743 linker_file_unregister_sysctls(file); 744 linker_file_sysuninit(file); 745 } 746 TAILQ_REMOVE(&linker_files, file, link); 747 748 if (file->deps) { 749 for (i = 0; i < file->ndeps; i++) 750 linker_file_unload(file->deps[i], flags); 751 free(file->deps, M_LINKER); 752 file->deps = NULL; 753 } 754 while ((cp = STAILQ_FIRST(&file->common)) != NULL) { 755 STAILQ_REMOVE_HEAD(&file->common, link); 756 free(cp, M_LINKER); 757 } 758 759 LINKER_UNLOAD(file); 760 761 EVENTHANDLER_INVOKE(kld_unload, file->filename, file->address, 762 file->size); 763 764 if (file->filename) { 765 free(file->filename, M_LINKER); 766 file->filename = NULL; 767 } 768 if (file->pathname) { 769 free(file->pathname, M_LINKER); 770 file->pathname = NULL; 771 } 772 kobj_delete((kobj_t) file, M_LINKER); 773 return (0); 774 } 775 776 int 777 linker_ctf_get(linker_file_t file, linker_ctf_t *lc) 778 { 779 return (LINKER_CTF_GET(file, lc)); 780 } 781 782 static int 783 linker_file_add_dependency(linker_file_t file, linker_file_t dep) 784 { 785 linker_file_t *newdeps; 786 787 sx_assert(&kld_sx, SA_XLOCKED); 788 file->deps = realloc(file->deps, (file->ndeps + 1) * sizeof(*newdeps), 789 M_LINKER, M_WAITOK | M_ZERO); 790 file->deps[file->ndeps] = dep; 791 file->ndeps++; 792 KLD_DPF(FILE, ("linker_file_add_dependency:" 793 " adding %s as dependency for %s\n", 794 dep->filename, file->filename)); 795 return (0); 796 } 797 798 /* 799 * Locate a linker set and its contents. This is a helper function to avoid 800 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **. 801 * This function is used in this file so we can avoid having lots of (void **) 802 * casts. 803 */ 804 int 805 linker_file_lookup_set(linker_file_t file, const char *name, 806 void *firstp, void *lastp, int *countp) 807 { 808 809 sx_assert(&kld_sx, SA_LOCKED); 810 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 811 } 812 813 /* 814 * List all functions in a file. 815 */ 816 int 817 linker_file_function_listall(linker_file_t lf, 818 linker_function_nameval_callback_t callback_func, void *arg) 819 { 820 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg)); 821 } 822 823 caddr_t 824 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 825 { 826 caddr_t sym; 827 int locked; 828 829 locked = sx_xlocked(&kld_sx); 830 if (!locked) 831 sx_xlock(&kld_sx); 832 sym = linker_file_lookup_symbol_internal(file, name, deps); 833 if (!locked) 834 sx_xunlock(&kld_sx); 835 return (sym); 836 } 837 838 static caddr_t 839 linker_file_lookup_symbol_internal(linker_file_t file, const char *name, 840 int deps) 841 { 842 c_linker_sym_t sym; 843 linker_symval_t symval; 844 caddr_t address; 845 size_t common_size = 0; 846 int i; 847 848 sx_assert(&kld_sx, SA_XLOCKED); 849 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 850 file, name, deps)); 851 852 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 853 LINKER_SYMBOL_VALUES(file, sym, &symval); 854 if (symval.value == 0) 855 /* 856 * For commons, first look them up in the 857 * dependencies and only allocate space if not found 858 * there. 859 */ 860 common_size = symval.size; 861 else { 862 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 863 ".value=%p\n", symval.value)); 864 return (symval.value); 865 } 866 } 867 if (deps) { 868 for (i = 0; i < file->ndeps; i++) { 869 address = linker_file_lookup_symbol_internal( 870 file->deps[i], name, 0); 871 if (address) { 872 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 873 " deps value=%p\n", address)); 874 return (address); 875 } 876 } 877 } 878 if (common_size > 0) { 879 /* 880 * This is a common symbol which was not found in the 881 * dependencies. We maintain a simple common symbol table in 882 * the file object. 883 */ 884 struct common_symbol *cp; 885 886 STAILQ_FOREACH(cp, &file->common, link) { 887 if (strcmp(cp->name, name) == 0) { 888 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 889 " old common value=%p\n", cp->address)); 890 return (cp->address); 891 } 892 } 893 /* 894 * Round the symbol size up to align. 895 */ 896 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 897 cp = malloc(sizeof(struct common_symbol) 898 + common_size + strlen(name) + 1, M_LINKER, 899 M_WAITOK | M_ZERO); 900 cp->address = (caddr_t)(cp + 1); 901 cp->name = cp->address + common_size; 902 strcpy(cp->name, name); 903 bzero(cp->address, common_size); 904 STAILQ_INSERT_TAIL(&file->common, cp, link); 905 906 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 907 " value=%p\n", cp->address)); 908 return (cp->address); 909 } 910 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 911 return (0); 912 } 913 914 /* 915 * Both DDB and stack(9) rely on the kernel linker to provide forward and 916 * backward lookup of symbols. However, DDB and sometimes stack(9) need to 917 * do this in a lockfree manner. We provide a set of internal helper 918 * routines to perform these operations without locks, and then wrappers that 919 * optionally lock. 920 * 921 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB. 922 */ 923 #ifdef DDB 924 static int 925 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym) 926 { 927 linker_file_t lf; 928 929 TAILQ_FOREACH(lf, &linker_files, link) { 930 if (LINKER_LOOKUP_DEBUG_SYMBOL(lf, symstr, sym) == 0) 931 return (0); 932 } 933 return (ENOENT); 934 } 935 #endif 936 937 static int 938 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 939 { 940 linker_file_t lf; 941 c_linker_sym_t best, es; 942 u_long diff, bestdiff, off; 943 944 best = 0; 945 off = (uintptr_t)value; 946 bestdiff = off; 947 TAILQ_FOREACH(lf, &linker_files, link) { 948 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 949 continue; 950 if (es != 0 && diff < bestdiff) { 951 best = es; 952 bestdiff = diff; 953 } 954 if (bestdiff == 0) 955 break; 956 } 957 if (best) { 958 *sym = best; 959 *diffp = bestdiff; 960 return (0); 961 } else { 962 *sym = 0; 963 *diffp = off; 964 return (ENOENT); 965 } 966 } 967 968 static int 969 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 970 { 971 linker_file_t lf; 972 973 TAILQ_FOREACH(lf, &linker_files, link) { 974 if (LINKER_DEBUG_SYMBOL_VALUES(lf, sym, symval) == 0) 975 return (0); 976 } 977 return (ENOENT); 978 } 979 980 static int 981 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen, 982 long *offset) 983 { 984 linker_symval_t symval; 985 c_linker_sym_t sym; 986 int error; 987 988 *offset = 0; 989 error = linker_debug_search_symbol(value, &sym, offset); 990 if (error) 991 return (error); 992 error = linker_debug_symbol_values(sym, &symval); 993 if (error) 994 return (error); 995 strlcpy(buf, symval.name, buflen); 996 return (0); 997 } 998 999 /* 1000 * DDB Helpers. DDB has to look across multiple files with their own symbol 1001 * tables and string tables. 1002 * 1003 * Note that we do not obey list locking protocols here. We really don't need 1004 * DDB to hang because somebody's got the lock held. We'll take the chance 1005 * that the files list is inconsistent instead. 1006 */ 1007 #ifdef DDB 1008 int 1009 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 1010 { 1011 1012 return (linker_debug_lookup(symstr, sym)); 1013 } 1014 #endif 1015 1016 int 1017 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 1018 { 1019 1020 return (linker_debug_search_symbol(value, sym, diffp)); 1021 } 1022 1023 int 1024 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 1025 { 1026 1027 return (linker_debug_symbol_values(sym, symval)); 1028 } 1029 1030 int 1031 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1032 long *offset) 1033 { 1034 1035 return (linker_debug_search_symbol_name(value, buf, buflen, offset)); 1036 } 1037 1038 /* 1039 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do 1040 * obey locking protocols, and offer a significantly less complex interface. 1041 */ 1042 int 1043 linker_search_symbol_name_flags(caddr_t value, char *buf, u_int buflen, 1044 long *offset, int flags) 1045 { 1046 int error; 1047 1048 KASSERT((flags & (M_NOWAIT | M_WAITOK)) != 0 && 1049 (flags & (M_NOWAIT | M_WAITOK)) != (M_NOWAIT | M_WAITOK), 1050 ("%s: bad flags: 0x%x", __func__, flags)); 1051 1052 if (flags & M_NOWAIT) { 1053 if (!sx_try_slock(&kld_sx)) 1054 return (EWOULDBLOCK); 1055 } else 1056 sx_slock(&kld_sx); 1057 1058 error = linker_debug_search_symbol_name(value, buf, buflen, offset); 1059 sx_sunlock(&kld_sx); 1060 return (error); 1061 } 1062 1063 int 1064 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1065 long *offset) 1066 { 1067 1068 return (linker_search_symbol_name_flags(value, buf, buflen, offset, 1069 M_WAITOK)); 1070 } 1071 1072 int 1073 linker_kldload_busy(int flags) 1074 { 1075 int error; 1076 1077 MPASS((flags & ~(LINKER_UB_UNLOCK | LINKER_UB_LOCKED | 1078 LINKER_UB_PCATCH)) == 0); 1079 if ((flags & LINKER_UB_LOCKED) != 0) 1080 sx_assert(&kld_sx, SA_XLOCKED); 1081 1082 if ((flags & LINKER_UB_LOCKED) == 0) 1083 sx_xlock(&kld_sx); 1084 while (kld_busy > 0) { 1085 if (kld_busy_owner == curthread) 1086 break; 1087 error = sx_sleep(&kld_busy, &kld_sx, 1088 (flags & LINKER_UB_PCATCH) != 0 ? PCATCH : 0, 1089 "kldbusy", 0); 1090 if (error != 0) { 1091 if ((flags & LINKER_UB_UNLOCK) != 0) 1092 sx_xunlock(&kld_sx); 1093 return (error); 1094 } 1095 } 1096 kld_busy++; 1097 kld_busy_owner = curthread; 1098 if ((flags & LINKER_UB_UNLOCK) != 0) 1099 sx_xunlock(&kld_sx); 1100 return (0); 1101 } 1102 1103 void 1104 linker_kldload_unbusy(int flags) 1105 { 1106 MPASS((flags & ~LINKER_UB_LOCKED) == 0); 1107 if ((flags & LINKER_UB_LOCKED) != 0) 1108 sx_assert(&kld_sx, SA_XLOCKED); 1109 1110 if ((flags & LINKER_UB_LOCKED) == 0) 1111 sx_xlock(&kld_sx); 1112 MPASS(kld_busy > 0); 1113 if (kld_busy_owner != curthread) 1114 panic("linker_kldload_unbusy done by not owning thread %p", 1115 kld_busy_owner); 1116 kld_busy--; 1117 if (kld_busy == 0) { 1118 kld_busy_owner = NULL; 1119 wakeup(&kld_busy); 1120 } 1121 sx_xunlock(&kld_sx); 1122 } 1123 1124 /* 1125 * Syscalls. 1126 */ 1127 int 1128 kern_kldload(struct thread *td, const char *file, int *fileid) 1129 { 1130 const char *kldname, *modname; 1131 linker_file_t lf; 1132 int error; 1133 1134 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1135 return (error); 1136 1137 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 1138 return (error); 1139 1140 /* 1141 * If file does not contain a qualified name or any dot in it 1142 * (kldname.ko, or kldname.ver.ko) treat it as an interface 1143 * name. 1144 */ 1145 if (strchr(file, '/') || strchr(file, '.')) { 1146 kldname = file; 1147 modname = NULL; 1148 } else { 1149 kldname = NULL; 1150 modname = file; 1151 } 1152 1153 error = linker_kldload_busy(LINKER_UB_PCATCH); 1154 if (error != 0) { 1155 sx_xunlock(&kld_sx); 1156 return (error); 1157 } 1158 1159 /* 1160 * It is possible that kldloaded module will attach a new ifnet, 1161 * so vnet context must be set when this ocurs. 1162 */ 1163 CURVNET_SET(TD_TO_VNET(td)); 1164 1165 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 1166 CURVNET_RESTORE(); 1167 1168 if (error == 0) { 1169 lf->userrefs++; 1170 if (fileid != NULL) 1171 *fileid = lf->id; 1172 } 1173 linker_kldload_unbusy(LINKER_UB_LOCKED); 1174 return (error); 1175 } 1176 1177 int 1178 sys_kldload(struct thread *td, struct kldload_args *uap) 1179 { 1180 char *pathname = NULL; 1181 int error, fileid; 1182 1183 td->td_retval[0] = -1; 1184 1185 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1186 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 1187 if (error == 0) { 1188 error = kern_kldload(td, pathname, &fileid); 1189 if (error == 0) 1190 td->td_retval[0] = fileid; 1191 } 1192 free(pathname, M_TEMP); 1193 return (error); 1194 } 1195 1196 int 1197 kern_kldunload(struct thread *td, int fileid, int flags) 1198 { 1199 linker_file_t lf; 1200 int error = 0; 1201 1202 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1203 return (error); 1204 1205 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 1206 return (error); 1207 1208 error = linker_kldload_busy(LINKER_UB_PCATCH); 1209 if (error != 0) { 1210 sx_xunlock(&kld_sx); 1211 return (error); 1212 } 1213 1214 CURVNET_SET(TD_TO_VNET(td)); 1215 lf = linker_find_file_by_id(fileid); 1216 if (lf) { 1217 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 1218 1219 if (lf->userrefs == 0) { 1220 /* 1221 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 1222 */ 1223 printf("kldunload: attempt to unload file that was" 1224 " loaded by the kernel\n"); 1225 error = EBUSY; 1226 } else { 1227 lf->userrefs--; 1228 error = linker_file_unload(lf, flags); 1229 if (error) 1230 lf->userrefs++; 1231 } 1232 } else 1233 error = ENOENT; 1234 CURVNET_RESTORE(); 1235 linker_kldload_unbusy(LINKER_UB_LOCKED); 1236 return (error); 1237 } 1238 1239 int 1240 sys_kldunload(struct thread *td, struct kldunload_args *uap) 1241 { 1242 1243 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 1244 } 1245 1246 int 1247 sys_kldunloadf(struct thread *td, struct kldunloadf_args *uap) 1248 { 1249 1250 if (uap->flags != LINKER_UNLOAD_NORMAL && 1251 uap->flags != LINKER_UNLOAD_FORCE) 1252 return (EINVAL); 1253 return (kern_kldunload(td, uap->fileid, uap->flags)); 1254 } 1255 1256 int 1257 sys_kldfind(struct thread *td, struct kldfind_args *uap) 1258 { 1259 char *pathname; 1260 const char *filename; 1261 linker_file_t lf; 1262 int error; 1263 1264 #ifdef MAC 1265 error = mac_kld_check_stat(td->td_ucred); 1266 if (error) 1267 return (error); 1268 #endif 1269 1270 td->td_retval[0] = -1; 1271 1272 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1273 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1274 goto out; 1275 1276 filename = linker_basename(pathname); 1277 sx_xlock(&kld_sx); 1278 lf = linker_find_file_by_name(filename); 1279 if (lf) 1280 td->td_retval[0] = lf->id; 1281 else 1282 error = ENOENT; 1283 sx_xunlock(&kld_sx); 1284 out: 1285 free(pathname, M_TEMP); 1286 return (error); 1287 } 1288 1289 int 1290 sys_kldnext(struct thread *td, struct kldnext_args *uap) 1291 { 1292 linker_file_t lf; 1293 int error = 0; 1294 1295 #ifdef MAC 1296 error = mac_kld_check_stat(td->td_ucred); 1297 if (error) 1298 return (error); 1299 #endif 1300 1301 sx_xlock(&kld_sx); 1302 if (uap->fileid == 0) 1303 lf = TAILQ_FIRST(&linker_files); 1304 else { 1305 lf = linker_find_file_by_id(uap->fileid); 1306 if (lf == NULL) { 1307 error = ENOENT; 1308 goto out; 1309 } 1310 lf = TAILQ_NEXT(lf, link); 1311 } 1312 1313 /* Skip partially loaded files. */ 1314 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1315 lf = TAILQ_NEXT(lf, link); 1316 1317 if (lf) 1318 td->td_retval[0] = lf->id; 1319 else 1320 td->td_retval[0] = 0; 1321 out: 1322 sx_xunlock(&kld_sx); 1323 return (error); 1324 } 1325 1326 int 1327 sys_kldstat(struct thread *td, struct kldstat_args *uap) 1328 { 1329 struct kld_file_stat *stat; 1330 int error, version; 1331 1332 /* 1333 * Check the version of the user's structure. 1334 */ 1335 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) 1336 != 0) 1337 return (error); 1338 if (version != sizeof(struct kld_file_stat_1) && 1339 version != sizeof(struct kld_file_stat)) 1340 return (EINVAL); 1341 1342 stat = malloc(sizeof(*stat), M_TEMP, M_WAITOK | M_ZERO); 1343 error = kern_kldstat(td, uap->fileid, stat); 1344 if (error == 0) 1345 error = copyout(stat, uap->stat, version); 1346 free(stat, M_TEMP); 1347 return (error); 1348 } 1349 1350 int 1351 kern_kldstat(struct thread *td, int fileid, struct kld_file_stat *stat) 1352 { 1353 linker_file_t lf; 1354 int namelen; 1355 #ifdef MAC 1356 int error; 1357 1358 error = mac_kld_check_stat(td->td_ucred); 1359 if (error) 1360 return (error); 1361 #endif 1362 1363 sx_xlock(&kld_sx); 1364 lf = linker_find_file_by_id(fileid); 1365 if (lf == NULL) { 1366 sx_xunlock(&kld_sx); 1367 return (ENOENT); 1368 } 1369 1370 /* Version 1 fields: */ 1371 namelen = strlen(lf->filename) + 1; 1372 if (namelen > sizeof(stat->name)) 1373 namelen = sizeof(stat->name); 1374 bcopy(lf->filename, &stat->name[0], namelen); 1375 stat->refs = lf->refs; 1376 stat->id = lf->id; 1377 stat->address = lf->address; 1378 stat->size = lf->size; 1379 /* Version 2 fields: */ 1380 namelen = strlen(lf->pathname) + 1; 1381 if (namelen > sizeof(stat->pathname)) 1382 namelen = sizeof(stat->pathname); 1383 bcopy(lf->pathname, &stat->pathname[0], namelen); 1384 sx_xunlock(&kld_sx); 1385 1386 td->td_retval[0] = 0; 1387 return (0); 1388 } 1389 1390 #ifdef DDB 1391 DB_COMMAND_FLAGS(kldstat, db_kldstat, DB_CMD_MEMSAFE) 1392 { 1393 linker_file_t lf; 1394 1395 #define POINTER_WIDTH ((int)(sizeof(void *) * 2 + 2)) 1396 db_printf("Id Refs Address%*c Size Name\n", POINTER_WIDTH - 7, ' '); 1397 #undef POINTER_WIDTH 1398 TAILQ_FOREACH(lf, &linker_files, link) { 1399 if (db_pager_quit) 1400 return; 1401 db_printf("%2d %4d %p %-8zx %s\n", lf->id, lf->refs, 1402 lf->address, lf->size, lf->filename); 1403 } 1404 } 1405 #endif /* DDB */ 1406 1407 int 1408 sys_kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1409 { 1410 linker_file_t lf; 1411 module_t mp; 1412 int error = 0; 1413 1414 #ifdef MAC 1415 error = mac_kld_check_stat(td->td_ucred); 1416 if (error) 1417 return (error); 1418 #endif 1419 1420 sx_xlock(&kld_sx); 1421 lf = linker_find_file_by_id(uap->fileid); 1422 if (lf) { 1423 MOD_SLOCK; 1424 mp = TAILQ_FIRST(&lf->modules); 1425 if (mp != NULL) 1426 td->td_retval[0] = module_getid(mp); 1427 else 1428 td->td_retval[0] = 0; 1429 MOD_SUNLOCK; 1430 } else 1431 error = ENOENT; 1432 sx_xunlock(&kld_sx); 1433 return (error); 1434 } 1435 1436 int 1437 sys_kldsym(struct thread *td, struct kldsym_args *uap) 1438 { 1439 char *symstr = NULL; 1440 c_linker_sym_t sym; 1441 linker_symval_t symval; 1442 linker_file_t lf; 1443 struct kld_sym_lookup lookup; 1444 int error = 0; 1445 1446 #ifdef MAC 1447 error = mac_kld_check_stat(td->td_ucred); 1448 if (error) 1449 return (error); 1450 #endif 1451 1452 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1453 return (error); 1454 if (lookup.version != sizeof(lookup) || 1455 uap->cmd != KLDSYM_LOOKUP) 1456 return (EINVAL); 1457 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1458 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1459 goto out; 1460 sx_xlock(&kld_sx); 1461 if (uap->fileid != 0) { 1462 lf = linker_find_file_by_id(uap->fileid); 1463 if (lf == NULL) 1464 error = ENOENT; 1465 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1466 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1467 lookup.symvalue = (uintptr_t) symval.value; 1468 lookup.symsize = symval.size; 1469 error = copyout(&lookup, uap->data, sizeof(lookup)); 1470 } else 1471 error = ENOENT; 1472 } else { 1473 TAILQ_FOREACH(lf, &linker_files, link) { 1474 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1475 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1476 lookup.symvalue = (uintptr_t)symval.value; 1477 lookup.symsize = symval.size; 1478 error = copyout(&lookup, uap->data, 1479 sizeof(lookup)); 1480 break; 1481 } 1482 } 1483 if (lf == NULL) 1484 error = ENOENT; 1485 } 1486 sx_xunlock(&kld_sx); 1487 out: 1488 free(symstr, M_TEMP); 1489 return (error); 1490 } 1491 1492 /* 1493 * Preloaded module support 1494 */ 1495 1496 static modlist_t 1497 modlist_lookup(const char *name, int ver) 1498 { 1499 modlist_t mod; 1500 1501 TAILQ_FOREACH(mod, &found_modules, link) { 1502 if (strcmp(mod->name, name) == 0 && 1503 (ver == 0 || mod->version == ver)) 1504 return (mod); 1505 } 1506 return (NULL); 1507 } 1508 1509 static modlist_t 1510 modlist_lookup2(const char *name, const struct mod_depend *verinfo) 1511 { 1512 modlist_t mod, bestmod; 1513 int ver; 1514 1515 if (verinfo == NULL) 1516 return (modlist_lookup(name, 0)); 1517 bestmod = NULL; 1518 TAILQ_FOREACH(mod, &found_modules, link) { 1519 if (strcmp(mod->name, name) != 0) 1520 continue; 1521 ver = mod->version; 1522 if (ver == verinfo->md_ver_preferred) 1523 return (mod); 1524 if (ver >= verinfo->md_ver_minimum && 1525 ver <= verinfo->md_ver_maximum && 1526 (bestmod == NULL || ver > bestmod->version)) 1527 bestmod = mod; 1528 } 1529 return (bestmod); 1530 } 1531 1532 static modlist_t 1533 modlist_newmodule(const char *modname, int version, linker_file_t container) 1534 { 1535 modlist_t mod; 1536 1537 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1538 if (mod == NULL) 1539 panic("no memory for module list"); 1540 mod->container = container; 1541 mod->name = modname; 1542 mod->version = version; 1543 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1544 return (mod); 1545 } 1546 1547 static void 1548 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1549 struct mod_metadata **stop, int preload) 1550 { 1551 struct mod_metadata *mp, **mdp; 1552 const char *modname; 1553 int ver; 1554 1555 for (mdp = start; mdp < stop; mdp++) { 1556 mp = *mdp; 1557 if (mp->md_type != MDT_VERSION) 1558 continue; 1559 modname = mp->md_cval; 1560 ver = ((const struct mod_version *)mp->md_data)->mv_version; 1561 if (modlist_lookup(modname, ver) != NULL) { 1562 printf("module %s already present!\n", modname); 1563 /* XXX what can we do? this is a build error. :-( */ 1564 continue; 1565 } 1566 modlist_newmodule(modname, ver, lf); 1567 } 1568 } 1569 1570 static void 1571 linker_preload(void *arg) 1572 { 1573 caddr_t modptr; 1574 const char *modname, *nmodname; 1575 char *modtype; 1576 linker_file_t lf, nlf; 1577 linker_class_t lc; 1578 int error; 1579 linker_file_list_t loaded_files; 1580 linker_file_list_t depended_files; 1581 struct mod_metadata *mp, *nmp; 1582 struct mod_metadata **start, **stop, **mdp, **nmdp; 1583 const struct mod_depend *verinfo; 1584 int nver; 1585 int resolves; 1586 modlist_t mod; 1587 struct sysinit **si_start, **si_stop; 1588 1589 TAILQ_INIT(&loaded_files); 1590 TAILQ_INIT(&depended_files); 1591 TAILQ_INIT(&found_modules); 1592 error = 0; 1593 1594 modptr = NULL; 1595 sx_xlock(&kld_sx); 1596 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1597 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1598 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1599 if (modname == NULL) { 1600 printf("Preloaded module at %p does not have a" 1601 " name!\n", modptr); 1602 continue; 1603 } 1604 if (modtype == NULL) { 1605 printf("Preloaded module at %p does not have a type!\n", 1606 modptr); 1607 continue; 1608 } 1609 if (bootverbose) 1610 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1611 modptr); 1612 lf = NULL; 1613 TAILQ_FOREACH(lc, &classes, link) { 1614 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1615 if (!error) 1616 break; 1617 lf = NULL; 1618 } 1619 if (lf) 1620 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1621 } 1622 1623 /* 1624 * First get a list of stuff in the kernel. 1625 */ 1626 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1627 &stop, NULL) == 0) 1628 linker_addmodules(linker_kernel_file, start, stop, 1); 1629 1630 /* 1631 * This is a once-off kinky bubble sort to resolve relocation 1632 * dependency requirements. 1633 */ 1634 restart: 1635 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1636 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1637 &stop, NULL); 1638 /* 1639 * First, look to see if we would successfully link with this 1640 * stuff. 1641 */ 1642 resolves = 1; /* unless we know otherwise */ 1643 if (!error) { 1644 for (mdp = start; mdp < stop; mdp++) { 1645 mp = *mdp; 1646 if (mp->md_type != MDT_DEPEND) 1647 continue; 1648 modname = mp->md_cval; 1649 verinfo = mp->md_data; 1650 for (nmdp = start; nmdp < stop; nmdp++) { 1651 nmp = *nmdp; 1652 if (nmp->md_type != MDT_VERSION) 1653 continue; 1654 nmodname = nmp->md_cval; 1655 if (strcmp(modname, nmodname) == 0) 1656 break; 1657 } 1658 if (nmdp < stop) /* it's a self reference */ 1659 continue; 1660 1661 /* 1662 * ok, the module isn't here yet, we 1663 * are not finished 1664 */ 1665 if (modlist_lookup2(modname, verinfo) == NULL) 1666 resolves = 0; 1667 } 1668 } 1669 /* 1670 * OK, if we found our modules, we can link. So, "provide" 1671 * the modules inside and add it to the end of the link order 1672 * list. 1673 */ 1674 if (resolves) { 1675 if (!error) { 1676 for (mdp = start; mdp < stop; mdp++) { 1677 mp = *mdp; 1678 if (mp->md_type != MDT_VERSION) 1679 continue; 1680 modname = mp->md_cval; 1681 nver = ((const struct mod_version *) 1682 mp->md_data)->mv_version; 1683 if (modlist_lookup(modname, 1684 nver) != NULL) { 1685 printf("module %s already" 1686 " present!\n", modname); 1687 TAILQ_REMOVE(&loaded_files, 1688 lf, loaded); 1689 linker_file_unload(lf, 1690 LINKER_UNLOAD_FORCE); 1691 /* we changed tailq next ptr */ 1692 goto restart; 1693 } 1694 modlist_newmodule(modname, nver, lf); 1695 } 1696 } 1697 TAILQ_REMOVE(&loaded_files, lf, loaded); 1698 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1699 /* 1700 * Since we provided modules, we need to restart the 1701 * sort so that the previous files that depend on us 1702 * have a chance. Also, we've busted the tailq next 1703 * pointer with the REMOVE. 1704 */ 1705 goto restart; 1706 } 1707 } 1708 1709 /* 1710 * At this point, we check to see what could not be resolved.. 1711 */ 1712 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1713 TAILQ_REMOVE(&loaded_files, lf, loaded); 1714 printf("KLD file %s is missing dependencies\n", lf->filename); 1715 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1716 } 1717 1718 /* 1719 * We made it. Finish off the linking in the order we determined. 1720 */ 1721 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1722 if (linker_kernel_file) { 1723 linker_kernel_file->refs++; 1724 error = linker_file_add_dependency(lf, 1725 linker_kernel_file); 1726 if (error) 1727 panic("cannot add dependency"); 1728 } 1729 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1730 &stop, NULL); 1731 if (!error) { 1732 for (mdp = start; mdp < stop; mdp++) { 1733 mp = *mdp; 1734 if (mp->md_type != MDT_DEPEND) 1735 continue; 1736 modname = mp->md_cval; 1737 verinfo = mp->md_data; 1738 mod = modlist_lookup2(modname, verinfo); 1739 if (mod == NULL) { 1740 printf("KLD file %s - cannot find " 1741 "dependency \"%s\"\n", 1742 lf->filename, modname); 1743 goto fail; 1744 } 1745 /* Don't count self-dependencies */ 1746 if (lf == mod->container) 1747 continue; 1748 mod->container->refs++; 1749 error = linker_file_add_dependency(lf, 1750 mod->container); 1751 if (error) 1752 panic("cannot add dependency"); 1753 } 1754 } 1755 /* 1756 * Now do relocation etc using the symbol search paths 1757 * established by the dependencies 1758 */ 1759 error = LINKER_LINK_PRELOAD_FINISH(lf); 1760 if (error) { 1761 printf("KLD file %s - could not finalize loading\n", 1762 lf->filename); 1763 goto fail; 1764 } 1765 linker_file_register_modules(lf); 1766 if (!TAILQ_EMPTY(&lf->modules)) 1767 lf->flags |= LINKER_FILE_MODULES; 1768 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1769 &si_stop, NULL) == 0) 1770 sysinit_add(si_start, si_stop); 1771 linker_file_register_sysctls(lf, true); 1772 lf->flags |= LINKER_FILE_LINKED; 1773 continue; 1774 fail: 1775 TAILQ_REMOVE(&depended_files, lf, loaded); 1776 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1777 } 1778 sx_xunlock(&kld_sx); 1779 /* woohoo! we made it! */ 1780 } 1781 1782 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, NULL); 1783 1784 /* 1785 * Handle preload files that failed to load any modules. 1786 */ 1787 static void 1788 linker_preload_finish(void *arg) 1789 { 1790 linker_file_t lf, nlf; 1791 1792 sx_xlock(&kld_sx); 1793 TAILQ_FOREACH_SAFE(lf, &linker_files, link, nlf) { 1794 /* 1795 * If all of the modules in this file failed to load, unload 1796 * the file and return an error of ENOEXEC. (Parity with 1797 * linker_load_file.) 1798 */ 1799 if ((lf->flags & LINKER_FILE_MODULES) != 0 && 1800 TAILQ_EMPTY(&lf->modules)) { 1801 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1802 continue; 1803 } 1804 1805 lf->flags &= ~LINKER_FILE_MODULES; 1806 lf->userrefs++; /* so we can (try to) kldunload it */ 1807 } 1808 sx_xunlock(&kld_sx); 1809 } 1810 1811 /* 1812 * Attempt to run after all DECLARE_MODULE SYSINITs. Unfortunately they can be 1813 * scheduled at any subsystem and order, so run this as late as possible. init 1814 * becomes runnable in SI_SUB_KTHREAD_INIT, so go slightly before that. 1815 */ 1816 SYSINIT(preload_finish, SI_SUB_KTHREAD_INIT - 100, SI_ORDER_MIDDLE, 1817 linker_preload_finish, NULL); 1818 1819 /* 1820 * Search for a not-loaded module by name. 1821 * 1822 * Modules may be found in the following locations: 1823 * 1824 * - preloaded (result is just the module name) - on disk (result is full path 1825 * to module) 1826 * 1827 * If the module name is qualified in any way (contains path, etc.) the we 1828 * simply return a copy of it. 1829 * 1830 * The search path can be manipulated via sysctl. Note that we use the ';' 1831 * character as a separator to be consistent with the bootloader. 1832 */ 1833 1834 static char linker_hintfile[] = "linker.hints"; 1835 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1836 1837 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RWTUN, linker_path, 1838 sizeof(linker_path), "module load search path"); 1839 1840 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1841 1842 static const char * const linker_ext_list[] = { 1843 "", 1844 ".ko", 1845 NULL 1846 }; 1847 1848 /* 1849 * Check if file actually exists either with or without extension listed in 1850 * the linker_ext_list. (probably should be generic for the rest of the 1851 * kernel) 1852 */ 1853 static char * 1854 linker_lookup_file(const char *path, int pathlen, const char *name, 1855 int namelen, struct vattr *vap) 1856 { 1857 struct nameidata nd; 1858 struct thread *td = curthread; /* XXX */ 1859 const char * const *cpp, *sep; 1860 char *result; 1861 int error, len, extlen, reclen, flags; 1862 __enum_uint8(vtype) type; 1863 1864 extlen = 0; 1865 for (cpp = linker_ext_list; *cpp; cpp++) { 1866 len = strlen(*cpp); 1867 if (len > extlen) 1868 extlen = len; 1869 } 1870 extlen++; /* trailing '\0' */ 1871 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1872 1873 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1874 result = malloc(reclen, M_LINKER, M_WAITOK); 1875 for (cpp = linker_ext_list; *cpp; cpp++) { 1876 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1877 namelen, name, *cpp); 1878 /* 1879 * Attempt to open the file, and return the path if 1880 * we succeed and it's a regular file. 1881 */ 1882 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result); 1883 flags = FREAD; 1884 error = vn_open(&nd, &flags, 0, NULL); 1885 if (error == 0) { 1886 NDFREE_PNBUF(&nd); 1887 type = nd.ni_vp->v_type; 1888 if (vap) 1889 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred); 1890 VOP_UNLOCK(nd.ni_vp); 1891 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1892 if (type == VREG) 1893 return (result); 1894 } 1895 } 1896 free(result, M_LINKER); 1897 return (NULL); 1898 } 1899 1900 #define INT_ALIGN(base, ptr) ptr = \ 1901 (base) + roundup2((ptr) - (base), sizeof(int)) 1902 1903 /* 1904 * Lookup KLD which contains requested module in the "linker.hints" file. If 1905 * version specification is available, then try to find the best KLD. 1906 * Otherwise just find the latest one. 1907 */ 1908 static char * 1909 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1910 int modnamelen, const struct mod_depend *verinfo) 1911 { 1912 struct thread *td = curthread; /* XXX */ 1913 struct ucred *cred = td ? td->td_ucred : NULL; 1914 struct nameidata nd; 1915 struct vattr vattr, mattr; 1916 const char *best, *sep; 1917 u_char *hints = NULL; 1918 u_char *cp, *recptr, *bufend, *result, *pathbuf; 1919 int error, ival, bestver, *intp, found, flags, clen, blen; 1920 ssize_t reclen; 1921 1922 result = NULL; 1923 bestver = found = 0; 1924 1925 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1926 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1927 strlen(sep) + 1; 1928 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1929 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1930 linker_hintfile); 1931 1932 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf); 1933 flags = FREAD; 1934 error = vn_open(&nd, &flags, 0, NULL); 1935 if (error) 1936 goto bad; 1937 NDFREE_PNBUF(&nd); 1938 if (nd.ni_vp->v_type != VREG) 1939 goto bad; 1940 best = cp = NULL; 1941 error = VOP_GETATTR(nd.ni_vp, &vattr, cred); 1942 if (error) 1943 goto bad; 1944 /* 1945 * XXX: we need to limit this number to some reasonable value 1946 */ 1947 if (vattr.va_size > LINKER_HINTS_MAX) { 1948 printf("linker.hints file too large %ld\n", (long)vattr.va_size); 1949 goto bad; 1950 } 1951 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1952 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1953 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1954 if (error) 1955 goto bad; 1956 VOP_UNLOCK(nd.ni_vp); 1957 vn_close(nd.ni_vp, FREAD, cred, td); 1958 nd.ni_vp = NULL; 1959 if (reclen != 0) { 1960 printf("can't read %zd\n", reclen); 1961 goto bad; 1962 } 1963 intp = (int *)hints; 1964 ival = *intp++; 1965 if (ival != LINKER_HINTS_VERSION) { 1966 printf("linker.hints file version mismatch %d\n", ival); 1967 goto bad; 1968 } 1969 bufend = hints + vattr.va_size; 1970 recptr = (u_char *)intp; 1971 clen = blen = 0; 1972 while (recptr < bufend && !found) { 1973 intp = (int *)recptr; 1974 reclen = *intp++; 1975 ival = *intp++; 1976 cp = (char *)intp; 1977 switch (ival) { 1978 case MDT_VERSION: 1979 clen = *cp++; 1980 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1981 break; 1982 cp += clen; 1983 INT_ALIGN(hints, cp); 1984 ival = *(int *)cp; 1985 cp += sizeof(int); 1986 clen = *cp++; 1987 if (verinfo == NULL || 1988 ival == verinfo->md_ver_preferred) { 1989 found = 1; 1990 break; 1991 } 1992 if (ival >= verinfo->md_ver_minimum && 1993 ival <= verinfo->md_ver_maximum && 1994 ival > bestver) { 1995 bestver = ival; 1996 best = cp; 1997 blen = clen; 1998 } 1999 break; 2000 default: 2001 break; 2002 } 2003 recptr += reclen + sizeof(int); 2004 } 2005 /* 2006 * Finally check if KLD is in the place 2007 */ 2008 if (found) 2009 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 2010 else if (best) 2011 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 2012 2013 /* 2014 * KLD is newer than hints file. What we should do now? 2015 */ 2016 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 2017 printf("warning: KLD '%s' is newer than the linker.hints" 2018 " file\n", result); 2019 bad: 2020 free(pathbuf, M_LINKER); 2021 if (hints) 2022 free(hints, M_TEMP); 2023 if (nd.ni_vp != NULL) { 2024 VOP_UNLOCK(nd.ni_vp); 2025 vn_close(nd.ni_vp, FREAD, cred, td); 2026 } 2027 /* 2028 * If nothing found or hints is absent - fallback to the old 2029 * way by using "kldname[.ko]" as module name. 2030 */ 2031 if (!found && !bestver && result == NULL) 2032 result = linker_lookup_file(path, pathlen, modname, 2033 modnamelen, NULL); 2034 return (result); 2035 } 2036 2037 /* 2038 * Lookup KLD which contains requested module in the all directories. 2039 */ 2040 static char * 2041 linker_search_module(const char *modname, int modnamelen, 2042 const struct mod_depend *verinfo) 2043 { 2044 char *cp, *ep, *result; 2045 2046 /* 2047 * traverse the linker path 2048 */ 2049 for (cp = linker_path; *cp; cp = ep + 1) { 2050 /* find the end of this component */ 2051 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 2052 result = linker_hints_lookup(cp, ep - cp, modname, 2053 modnamelen, verinfo); 2054 if (result != NULL) 2055 return (result); 2056 if (*ep == 0) 2057 break; 2058 } 2059 return (NULL); 2060 } 2061 2062 /* 2063 * Search for module in all directories listed in the linker_path. 2064 */ 2065 static char * 2066 linker_search_kld(const char *name) 2067 { 2068 char *cp, *ep, *result; 2069 int len; 2070 2071 /* qualified at all? */ 2072 if (strchr(name, '/')) 2073 return (strdup(name, M_LINKER)); 2074 2075 /* traverse the linker path */ 2076 len = strlen(name); 2077 for (ep = linker_path; *ep; ep++) { 2078 cp = ep; 2079 /* find the end of this component */ 2080 for (; *ep != 0 && *ep != ';'; ep++); 2081 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 2082 if (result != NULL) 2083 return (result); 2084 } 2085 return (NULL); 2086 } 2087 2088 static const char * 2089 linker_basename(const char *path) 2090 { 2091 const char *filename; 2092 2093 filename = strrchr(path, '/'); 2094 if (filename == NULL) 2095 return path; 2096 if (filename[1]) 2097 filename++; 2098 return (filename); 2099 } 2100 2101 #ifdef HWPMC_HOOKS 2102 /* 2103 * Inform hwpmc about the set of kernel modules currently loaded. 2104 */ 2105 void * 2106 linker_hwpmc_list_objects(void) 2107 { 2108 linker_file_t lf; 2109 struct pmckern_map_in *kobase; 2110 int i, nmappings; 2111 2112 nmappings = 0; 2113 sx_slock(&kld_sx); 2114 TAILQ_FOREACH(lf, &linker_files, link) 2115 nmappings++; 2116 2117 /* Allocate nmappings + 1 entries. */ 2118 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in), 2119 M_LINKER, M_WAITOK | M_ZERO); 2120 i = 0; 2121 TAILQ_FOREACH(lf, &linker_files, link) { 2122 /* Save the info for this linker file. */ 2123 kobase[i].pm_file = lf->pathname; 2124 kobase[i].pm_address = (uintptr_t)lf->address; 2125 i++; 2126 } 2127 sx_sunlock(&kld_sx); 2128 2129 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?")); 2130 2131 /* The last entry of the malloced area comprises of all zeros. */ 2132 KASSERT(kobase[i].pm_file == NULL, 2133 ("linker_hwpmc_list_objects: last object not NULL")); 2134 2135 return ((void *)kobase); 2136 } 2137 #endif 2138 2139 /* check if root file system is not mounted */ 2140 static bool 2141 linker_root_mounted(void) 2142 { 2143 struct pwd *pwd; 2144 bool ret; 2145 2146 if (rootvnode == NULL) 2147 return (false); 2148 2149 pwd = pwd_hold(curthread); 2150 ret = pwd->pwd_rdir != NULL; 2151 pwd_drop(pwd); 2152 return (ret); 2153 } 2154 2155 /* 2156 * Find a file which contains given module and load it, if "parent" is not 2157 * NULL, register a reference to it. 2158 */ 2159 static int 2160 linker_load_module(const char *kldname, const char *modname, 2161 struct linker_file *parent, const struct mod_depend *verinfo, 2162 struct linker_file **lfpp) 2163 { 2164 linker_file_t lfdep; 2165 const char *filename; 2166 char *pathname; 2167 int error; 2168 2169 sx_assert(&kld_sx, SA_XLOCKED); 2170 if (modname == NULL) { 2171 /* 2172 * We have to load KLD 2173 */ 2174 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 2175 " is not NULL")); 2176 if (!linker_root_mounted()) 2177 return (ENXIO); 2178 pathname = linker_search_kld(kldname); 2179 } else { 2180 if (modlist_lookup2(modname, verinfo) != NULL) 2181 return (EEXIST); 2182 if (!linker_root_mounted()) 2183 return (ENXIO); 2184 if (kldname != NULL) 2185 pathname = strdup(kldname, M_LINKER); 2186 else 2187 /* 2188 * Need to find a KLD with required module 2189 */ 2190 pathname = linker_search_module(modname, 2191 strlen(modname), verinfo); 2192 } 2193 if (pathname == NULL) 2194 return (ENOENT); 2195 2196 /* 2197 * Can't load more than one file with the same basename XXX: 2198 * Actually it should be possible to have multiple KLDs with 2199 * the same basename but different path because they can 2200 * provide different versions of the same modules. 2201 */ 2202 filename = linker_basename(pathname); 2203 if (linker_find_file_by_name(filename)) 2204 error = EEXIST; 2205 else do { 2206 error = linker_load_file(pathname, &lfdep); 2207 if (error) 2208 break; 2209 if (modname && verinfo && 2210 modlist_lookup2(modname, verinfo) == NULL) { 2211 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 2212 error = ENOENT; 2213 break; 2214 } 2215 if (parent) { 2216 error = linker_file_add_dependency(parent, lfdep); 2217 if (error) 2218 break; 2219 } 2220 if (lfpp) 2221 *lfpp = lfdep; 2222 } while (0); 2223 free(pathname, M_LINKER); 2224 return (error); 2225 } 2226 2227 /* 2228 * This routine is responsible for finding dependencies of userland initiated 2229 * kldload(2)'s of files. 2230 */ 2231 int 2232 linker_load_dependencies(linker_file_t lf) 2233 { 2234 linker_file_t lfdep; 2235 struct mod_metadata **start, **stop, **mdp, **nmdp; 2236 struct mod_metadata *mp, *nmp; 2237 const struct mod_depend *verinfo; 2238 modlist_t mod; 2239 const char *modname, *nmodname; 2240 int ver, error = 0; 2241 2242 /* 2243 * All files are dependent on /kernel. 2244 */ 2245 sx_assert(&kld_sx, SA_XLOCKED); 2246 if (linker_kernel_file) { 2247 linker_kernel_file->refs++; 2248 error = linker_file_add_dependency(lf, linker_kernel_file); 2249 if (error) 2250 return (error); 2251 } 2252 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 2253 NULL) != 0) 2254 return (0); 2255 for (mdp = start; mdp < stop; mdp++) { 2256 mp = *mdp; 2257 if (mp->md_type != MDT_VERSION) 2258 continue; 2259 modname = mp->md_cval; 2260 ver = ((const struct mod_version *)mp->md_data)->mv_version; 2261 mod = modlist_lookup(modname, ver); 2262 if (mod != NULL) { 2263 printf("interface %s.%d already present in the KLD" 2264 " '%s'!\n", modname, ver, 2265 mod->container->filename); 2266 return (EEXIST); 2267 } 2268 } 2269 2270 for (mdp = start; mdp < stop; mdp++) { 2271 mp = *mdp; 2272 if (mp->md_type != MDT_DEPEND) 2273 continue; 2274 modname = mp->md_cval; 2275 verinfo = mp->md_data; 2276 nmodname = NULL; 2277 for (nmdp = start; nmdp < stop; nmdp++) { 2278 nmp = *nmdp; 2279 if (nmp->md_type != MDT_VERSION) 2280 continue; 2281 nmodname = nmp->md_cval; 2282 if (strcmp(modname, nmodname) == 0) 2283 break; 2284 } 2285 if (nmdp < stop)/* early exit, it's a self reference */ 2286 continue; 2287 mod = modlist_lookup2(modname, verinfo); 2288 if (mod) { /* woohoo, it's loaded already */ 2289 lfdep = mod->container; 2290 lfdep->refs++; 2291 error = linker_file_add_dependency(lf, lfdep); 2292 if (error) 2293 break; 2294 continue; 2295 } 2296 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 2297 if (error) { 2298 printf("KLD %s: depends on %s - not available or" 2299 " version mismatch\n", lf->filename, modname); 2300 break; 2301 } 2302 } 2303 2304 if (error) 2305 return (error); 2306 linker_addmodules(lf, start, stop, 0); 2307 return (error); 2308 } 2309 2310 static int 2311 sysctl_kern_function_list_iterate(const char *name, void *opaque) 2312 { 2313 struct sysctl_req *req; 2314 2315 req = opaque; 2316 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 2317 } 2318 2319 /* 2320 * Export a nul-separated, double-nul-terminated list of all function names 2321 * in the kernel. 2322 */ 2323 static int 2324 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 2325 { 2326 linker_file_t lf; 2327 int error; 2328 2329 #ifdef MAC 2330 error = mac_kld_check_stat(req->td->td_ucred); 2331 if (error) 2332 return (error); 2333 #endif 2334 error = sysctl_wire_old_buffer(req, 0); 2335 if (error != 0) 2336 return (error); 2337 sx_xlock(&kld_sx); 2338 TAILQ_FOREACH(lf, &linker_files, link) { 2339 error = LINKER_EACH_FUNCTION_NAME(lf, 2340 sysctl_kern_function_list_iterate, req); 2341 if (error) { 2342 sx_xunlock(&kld_sx); 2343 return (error); 2344 } 2345 } 2346 sx_xunlock(&kld_sx); 2347 return (SYSCTL_OUT(req, "", 1)); 2348 } 2349 2350 SYSCTL_PROC(_kern, OID_AUTO, function_list, 2351 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 2352 sysctl_kern_function_list, "", 2353 "kernel function list"); 2354