Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_linker.c
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1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1997-2000 Doug Rabson 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include "opt_ddb.h" 33 #include "opt_kld.h" 34 #include "opt_hwpmc_hooks.h" 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/boottrace.h> 39 #include <sys/eventhandler.h> 40 #include <sys/fcntl.h> 41 #include <sys/jail.h> 42 #include <sys/kernel.h> 43 #include <sys/libkern.h> 44 #include <sys/linker.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/module.h> 48 #include <sys/mount.h> 49 #include <sys/mutex.h> 50 #include <sys/namei.h> 51 #include <sys/priv.h> 52 #include <sys/proc.h> 53 #include <sys/sx.h> 54 #include <sys/syscallsubr.h> 55 #include <sys/sysctl.h> 56 #include <sys/sysproto.h> 57 #include <sys/vnode.h> 58 59 #ifdef DDB 60 #include <ddb/ddb.h> 61 #endif 62 63 #include <net/vnet.h> 64 65 #include <security/mac/mac_framework.h> 66 67 #include "linker_if.h" 68 69 #ifdef HWPMC_HOOKS 70 #include <sys/pmckern.h> 71 #endif 72 73 #ifdef KLD_DEBUG 74 int kld_debug = 0; 75 SYSCTL_INT(_debug, OID_AUTO, kld_debug, CTLFLAG_RWTUN, 76 &kld_debug, 0, "Set various levels of KLD debug"); 77 #endif 78 79 /* These variables are used by kernel debuggers to enumerate loaded files. */ 80 const int kld_off_address = offsetof(struct linker_file, address); 81 const int kld_off_filename = offsetof(struct linker_file, filename); 82 const int kld_off_pathname = offsetof(struct linker_file, pathname); 83 const int kld_off_next = offsetof(struct linker_file, link.tqe_next); 84 85 /* 86 * static char *linker_search_path(const char *name, struct mod_depend 87 * *verinfo); 88 */ 89 static const char *linker_basename(const char *path); 90 91 /* 92 * Find a currently loaded file given its filename. 93 */ 94 static linker_file_t linker_find_file_by_name(const char* _filename); 95 96 /* 97 * Find a currently loaded file given its file id. 98 */ 99 static linker_file_t linker_find_file_by_id(int _fileid); 100 101 /* Metadata from the static kernel */ 102 SET_DECLARE(modmetadata_set, struct mod_metadata); 103 104 MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 105 106 linker_file_t linker_kernel_file; 107 108 static struct sx kld_sx; /* kernel linker lock */ 109 static u_int kld_busy; 110 static struct thread *kld_busy_owner; 111 112 /* 113 * Load counter used by clients to determine if a linker file has been 114 * re-loaded. This counter is incremented for each file load. 115 */ 116 static int loadcnt; 117 118 static linker_class_list_t classes; 119 static linker_file_list_t linker_files; 120 static int next_file_id = 1; 121 static int linker_no_more_classes = 0; 122 123 #define LINKER_GET_NEXT_FILE_ID(a) do { \ 124 linker_file_t lftmp; \ 125 \ 126 if (!cold) \ 127 sx_assert(&kld_sx, SA_XLOCKED); \ 128 retry: \ 129 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 130 if (next_file_id == lftmp->id) { \ 131 next_file_id++; \ 132 goto retry; \ 133 } \ 134 } \ 135 (a) = next_file_id; \ 136 } while (0) 137 138 /* XXX wrong name; we're looking at version provision tags here, not modules */ 139 typedef TAILQ_HEAD(, modlist) modlisthead_t; 140 struct modlist { 141 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 142 linker_file_t container; 143 const char *name; 144 int version; 145 }; 146 typedef struct modlist *modlist_t; 147 static modlisthead_t found_modules; 148 149 static int linker_file_add_dependency(linker_file_t file, 150 linker_file_t dep); 151 static caddr_t linker_file_lookup_symbol_internal(linker_file_t file, 152 const char* name, int deps); 153 static int linker_load_module(const char *kldname, 154 const char *modname, struct linker_file *parent, 155 const struct mod_depend *verinfo, struct linker_file **lfpp); 156 static modlist_t modlist_lookup2(const char *name, const struct mod_depend *verinfo); 157 158 static void 159 linker_init(void *arg) 160 { 161 162 sx_init(&kld_sx, "kernel linker"); 163 TAILQ_INIT(&classes); 164 TAILQ_INIT(&linker_files); 165 } 166 167 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, NULL); 168 169 static void 170 linker_stop_class_add(void *arg) 171 { 172 173 linker_no_more_classes = 1; 174 } 175 176 SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL); 177 178 int 179 linker_add_class(linker_class_t lc) 180 { 181 182 /* 183 * We disallow any class registration past SI_ORDER_ANY 184 * of SI_SUB_KLD. We bump the reference count to keep the 185 * ops from being freed. 186 */ 187 if (linker_no_more_classes == 1) 188 return (EPERM); 189 kobj_class_compile((kobj_class_t) lc); 190 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */ 191 TAILQ_INSERT_TAIL(&classes, lc, link); 192 return (0); 193 } 194 195 static void 196 linker_file_sysinit(linker_file_t lf) 197 { 198 struct sysinit **start, **stop, **sipp, **xipp, *save; 199 int last; 200 201 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 202 lf->filename)); 203 204 sx_assert(&kld_sx, SA_XLOCKED); 205 206 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 207 return; 208 /* 209 * Perform a bubble sort of the system initialization objects by 210 * their subsystem (primary key) and order (secondary key). 211 * 212 * Since some things care about execution order, this is the operation 213 * which ensures continued function. 214 */ 215 for (sipp = start; sipp < stop; sipp++) { 216 for (xipp = sipp + 1; xipp < stop; xipp++) { 217 if ((*sipp)->subsystem < (*xipp)->subsystem || 218 ((*sipp)->subsystem == (*xipp)->subsystem && 219 (*sipp)->order <= (*xipp)->order)) 220 continue; /* skip */ 221 save = *sipp; 222 *sipp = *xipp; 223 *xipp = save; 224 } 225 } 226 227 /* 228 * Traverse the (now) ordered list of system initialization tasks. 229 * Perform each task, and continue on to the next task. 230 */ 231 last = SI_SUB_DUMMY; 232 sx_xunlock(&kld_sx); 233 mtx_lock(&Giant); 234 for (sipp = start; sipp < stop; sipp++) { 235 if ((*sipp)->subsystem == SI_SUB_DUMMY) 236 continue; /* skip dummy task(s) */ 237 238 if ((*sipp)->subsystem > last) 239 BOOTTRACE("%s: sysinit 0x%7x", lf->filename, 240 (*sipp)->subsystem); 241 242 /* Call function */ 243 (*((*sipp)->func)) ((*sipp)->udata); 244 last = (*sipp)->subsystem; 245 } 246 mtx_unlock(&Giant); 247 sx_xlock(&kld_sx); 248 } 249 250 static void 251 linker_file_sysuninit(linker_file_t lf) 252 { 253 struct sysinit **start, **stop, **sipp, **xipp, *save; 254 int last; 255 256 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 257 lf->filename)); 258 259 sx_assert(&kld_sx, SA_XLOCKED); 260 261 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 262 NULL) != 0) 263 return; 264 265 /* 266 * Perform a reverse bubble sort of the system initialization objects 267 * by their subsystem (primary key) and order (secondary key). 268 * 269 * Since some things care about execution order, this is the operation 270 * which ensures continued function. 271 */ 272 for (sipp = start; sipp < stop; sipp++) { 273 for (xipp = sipp + 1; xipp < stop; xipp++) { 274 if ((*sipp)->subsystem > (*xipp)->subsystem || 275 ((*sipp)->subsystem == (*xipp)->subsystem && 276 (*sipp)->order >= (*xipp)->order)) 277 continue; /* skip */ 278 save = *sipp; 279 *sipp = *xipp; 280 *xipp = save; 281 } 282 } 283 284 /* 285 * Traverse the (now) ordered list of system initialization tasks. 286 * Perform each task, and continue on to the next task. 287 */ 288 sx_xunlock(&kld_sx); 289 mtx_lock(&Giant); 290 last = SI_SUB_DUMMY; 291 for (sipp = start; sipp < stop; sipp++) { 292 if ((*sipp)->subsystem == SI_SUB_DUMMY) 293 continue; /* skip dummy task(s) */ 294 295 if ((*sipp)->subsystem > last) 296 BOOTTRACE("%s: sysuninit 0x%7x", lf->filename, 297 (*sipp)->subsystem); 298 299 /* Call function */ 300 (*((*sipp)->func)) ((*sipp)->udata); 301 last = (*sipp)->subsystem; 302 } 303 mtx_unlock(&Giant); 304 sx_xlock(&kld_sx); 305 } 306 307 static void 308 linker_file_register_sysctls(linker_file_t lf, bool enable) 309 { 310 struct sysctl_oid **start, **stop, **oidp; 311 312 KLD_DPF(FILE, 313 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 314 lf->filename)); 315 316 sx_assert(&kld_sx, SA_XLOCKED); 317 318 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 319 return; 320 321 sx_xunlock(&kld_sx); 322 sysctl_wlock(); 323 for (oidp = start; oidp < stop; oidp++) { 324 if (enable) 325 sysctl_register_oid(*oidp); 326 else 327 sysctl_register_disabled_oid(*oidp); 328 } 329 sysctl_wunlock(); 330 sx_xlock(&kld_sx); 331 } 332 333 static void 334 linker_file_enable_sysctls(linker_file_t lf) 335 { 336 struct sysctl_oid **start, **stop, **oidp; 337 338 KLD_DPF(FILE, 339 ("linker_file_enable_sysctls: enable SYSCTLs for %s\n", 340 lf->filename)); 341 342 sx_assert(&kld_sx, SA_XLOCKED); 343 344 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 345 return; 346 347 sx_xunlock(&kld_sx); 348 sysctl_wlock(); 349 for (oidp = start; oidp < stop; oidp++) 350 sysctl_enable_oid(*oidp); 351 sysctl_wunlock(); 352 sx_xlock(&kld_sx); 353 } 354 355 static void 356 linker_file_unregister_sysctls(linker_file_t lf) 357 { 358 struct sysctl_oid **start, **stop, **oidp; 359 360 KLD_DPF(FILE, ("linker_file_unregister_sysctls: unregistering SYSCTLs" 361 " for %s\n", lf->filename)); 362 363 sx_assert(&kld_sx, SA_XLOCKED); 364 365 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 366 return; 367 368 sx_xunlock(&kld_sx); 369 sysctl_wlock(); 370 for (oidp = start; oidp < stop; oidp++) 371 sysctl_unregister_oid(*oidp); 372 sysctl_wunlock(); 373 sx_xlock(&kld_sx); 374 } 375 376 static int 377 linker_file_register_modules(linker_file_t lf) 378 { 379 struct mod_metadata **start, **stop, **mdp; 380 const moduledata_t *moddata; 381 int first_error, error; 382 383 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 384 " in %s\n", lf->filename)); 385 386 sx_assert(&kld_sx, SA_XLOCKED); 387 388 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL) != 0) { 389 /* 390 * This fallback should be unnecessary, but if we get booted 391 * from boot2 instead of loader and we are missing our 392 * metadata then we have to try the best we can. 393 */ 394 if (lf == linker_kernel_file) { 395 start = SET_BEGIN(modmetadata_set); 396 stop = SET_LIMIT(modmetadata_set); 397 } else 398 return (0); 399 } 400 first_error = 0; 401 for (mdp = start; mdp < stop; mdp++) { 402 if ((*mdp)->md_type != MDT_MODULE) 403 continue; 404 moddata = (*mdp)->md_data; 405 KLD_DPF(FILE, ("Registering module %s in %s\n", 406 moddata->name, lf->filename)); 407 error = module_register(moddata, lf); 408 if (error) { 409 printf("Module %s failed to register: %d\n", 410 moddata->name, error); 411 if (first_error == 0) 412 first_error = error; 413 } 414 } 415 return (first_error); 416 } 417 418 static void 419 linker_init_kernel_modules(void) 420 { 421 422 sx_xlock(&kld_sx); 423 linker_file_register_modules(linker_kernel_file); 424 sx_xunlock(&kld_sx); 425 } 426 427 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 428 NULL); 429 430 static int 431 linker_load_file(const char *filename, linker_file_t *result) 432 { 433 linker_class_t lc; 434 linker_file_t lf; 435 int foundfile, error, modules; 436 437 /* Refuse to load modules if securelevel raised */ 438 if (prison0.pr_securelevel > 0) 439 return (EPERM); 440 441 sx_assert(&kld_sx, SA_XLOCKED); 442 lf = linker_find_file_by_name(filename); 443 if (lf) { 444 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 445 " incrementing refs\n", filename)); 446 *result = lf; 447 lf->refs++; 448 return (0); 449 } 450 foundfile = 0; 451 error = 0; 452 453 /* 454 * We do not need to protect (lock) classes here because there is 455 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 456 * and there is no class deregistration mechanism at this time. 457 */ 458 TAILQ_FOREACH(lc, &classes, link) { 459 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 460 filename)); 461 error = LINKER_LOAD_FILE(lc, filename, &lf); 462 /* 463 * If we got something other than ENOENT, then it exists but 464 * we cannot load it for some other reason. 465 */ 466 if (error != ENOENT) 467 foundfile = 1; 468 if (lf) { 469 error = linker_file_register_modules(lf); 470 if (error == EEXIST) { 471 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 472 return (error); 473 } 474 modules = !TAILQ_EMPTY(&lf->modules); 475 linker_file_register_sysctls(lf, false); 476 linker_file_sysinit(lf); 477 lf->flags |= LINKER_FILE_LINKED; 478 479 /* 480 * If all of the modules in this file failed 481 * to load, unload the file and return an 482 * error of ENOEXEC. 483 */ 484 if (modules && TAILQ_EMPTY(&lf->modules)) { 485 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 486 return (ENOEXEC); 487 } 488 linker_file_enable_sysctls(lf); 489 EVENTHANDLER_INVOKE(kld_load, lf); 490 *result = lf; 491 return (0); 492 } 493 } 494 /* 495 * Less than ideal, but tells the user whether it failed to load or 496 * the module was not found. 497 */ 498 if (foundfile) { 499 /* 500 * If the file type has not been recognized by the last try 501 * printout a message before to fail. 502 */ 503 if (error == ENOSYS) 504 printf("%s: %s - unsupported file type\n", 505 __func__, filename); 506 507 /* 508 * Format not recognized or otherwise unloadable. 509 * When loading a module that is statically built into 510 * the kernel EEXIST percolates back up as the return 511 * value. Preserve this so that apps like sysinstall 512 * can recognize this special case and not post bogus 513 * dialog boxes. 514 */ 515 if (error != EEXIST) 516 error = ENOEXEC; 517 } else 518 error = ENOENT; /* Nothing found */ 519 return (error); 520 } 521 522 int 523 linker_reference_module(const char *modname, struct mod_depend *verinfo, 524 linker_file_t *result) 525 { 526 modlist_t mod; 527 int error; 528 529 sx_xlock(&kld_sx); 530 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 531 *result = mod->container; 532 (*result)->refs++; 533 sx_xunlock(&kld_sx); 534 return (0); 535 } 536 537 error = linker_load_module(NULL, modname, NULL, verinfo, result); 538 sx_xunlock(&kld_sx); 539 return (error); 540 } 541 542 int 543 linker_release_module(const char *modname, struct mod_depend *verinfo, 544 linker_file_t lf) 545 { 546 modlist_t mod; 547 int error; 548 549 sx_xlock(&kld_sx); 550 if (lf == NULL) { 551 KASSERT(modname != NULL, 552 ("linker_release_module: no file or name")); 553 mod = modlist_lookup2(modname, verinfo); 554 if (mod == NULL) { 555 sx_xunlock(&kld_sx); 556 return (ESRCH); 557 } 558 lf = mod->container; 559 } else 560 KASSERT(modname == NULL && verinfo == NULL, 561 ("linker_release_module: both file and name")); 562 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL); 563 sx_xunlock(&kld_sx); 564 return (error); 565 } 566 567 static linker_file_t 568 linker_find_file_by_name(const char *filename) 569 { 570 linker_file_t lf; 571 char *koname; 572 573 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 574 sprintf(koname, "%s.ko", filename); 575 576 sx_assert(&kld_sx, SA_XLOCKED); 577 TAILQ_FOREACH(lf, &linker_files, link) { 578 if (strcmp(lf->filename, koname) == 0) 579 break; 580 if (strcmp(lf->filename, filename) == 0) 581 break; 582 } 583 free(koname, M_LINKER); 584 return (lf); 585 } 586 587 static linker_file_t 588 linker_find_file_by_id(int fileid) 589 { 590 linker_file_t lf; 591 592 sx_assert(&kld_sx, SA_XLOCKED); 593 TAILQ_FOREACH(lf, &linker_files, link) 594 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED) 595 break; 596 return (lf); 597 } 598 599 int 600 linker_file_foreach(linker_predicate_t *predicate, void *context) 601 { 602 linker_file_t lf; 603 int retval = 0; 604 605 sx_xlock(&kld_sx); 606 TAILQ_FOREACH(lf, &linker_files, link) { 607 retval = predicate(lf, context); 608 if (retval != 0) 609 break; 610 } 611 sx_xunlock(&kld_sx); 612 return (retval); 613 } 614 615 linker_file_t 616 linker_make_file(const char *pathname, linker_class_t lc) 617 { 618 linker_file_t lf; 619 const char *filename; 620 621 if (!cold) 622 sx_assert(&kld_sx, SA_XLOCKED); 623 filename = linker_basename(pathname); 624 625 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname)); 626 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 627 if (lf == NULL) 628 return (NULL); 629 lf->ctors_addr = 0; 630 lf->ctors_size = 0; 631 lf->dtors_addr = 0; 632 lf->dtors_size = 0; 633 lf->refs = 1; 634 lf->userrefs = 0; 635 lf->flags = 0; 636 lf->filename = strdup(filename, M_LINKER); 637 lf->pathname = strdup(pathname, M_LINKER); 638 LINKER_GET_NEXT_FILE_ID(lf->id); 639 lf->ndeps = 0; 640 lf->deps = NULL; 641 lf->loadcnt = ++loadcnt; 642 #ifdef __arm__ 643 lf->exidx_addr = 0; 644 lf->exidx_size = 0; 645 #endif 646 STAILQ_INIT(&lf->common); 647 TAILQ_INIT(&lf->modules); 648 TAILQ_INSERT_TAIL(&linker_files, lf, link); 649 return (lf); 650 } 651 652 int 653 linker_file_unload(linker_file_t file, int flags) 654 { 655 module_t mod, next; 656 modlist_t ml, nextml; 657 struct common_symbol *cp; 658 int error, i; 659 660 /* Refuse to unload modules if securelevel raised. */ 661 if (prison0.pr_securelevel > 0) 662 return (EPERM); 663 664 sx_assert(&kld_sx, SA_XLOCKED); 665 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 666 667 /* Easy case of just dropping a reference. */ 668 if (file->refs > 1) { 669 file->refs--; 670 return (0); 671 } 672 673 /* Give eventhandlers a chance to prevent the unload. */ 674 error = 0; 675 EVENTHANDLER_INVOKE(kld_unload_try, file, &error); 676 if (error != 0) 677 return (EBUSY); 678 679 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 680 " informing modules\n")); 681 682 /* 683 * Quiesce all the modules to give them a chance to veto the unload. 684 */ 685 MOD_SLOCK; 686 for (mod = TAILQ_FIRST(&file->modules); mod; 687 mod = module_getfnext(mod)) { 688 error = module_quiesce(mod); 689 if (error != 0 && flags != LINKER_UNLOAD_FORCE) { 690 KLD_DPF(FILE, ("linker_file_unload: module %s" 691 " vetoed unload\n", module_getname(mod))); 692 /* 693 * XXX: Do we need to tell all the quiesced modules 694 * that they can resume work now via a new module 695 * event? 696 */ 697 MOD_SUNLOCK; 698 return (error); 699 } 700 } 701 MOD_SUNLOCK; 702 703 /* 704 * Inform any modules associated with this file that they are 705 * being unloaded. 706 */ 707 MOD_XLOCK; 708 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 709 next = module_getfnext(mod); 710 MOD_XUNLOCK; 711 712 /* 713 * Give the module a chance to veto the unload. 714 */ 715 if ((error = module_unload(mod)) != 0) { 716 #ifdef KLD_DEBUG 717 MOD_SLOCK; 718 KLD_DPF(FILE, ("linker_file_unload: module %s" 719 " failed unload\n", module_getname(mod))); 720 MOD_SUNLOCK; 721 #endif 722 return (error); 723 } 724 MOD_XLOCK; 725 module_release(mod); 726 } 727 MOD_XUNLOCK; 728 729 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 730 if (ml->container == file) { 731 TAILQ_REMOVE(&found_modules, ml, link); 732 free(ml, M_LINKER); 733 } 734 } 735 736 /* 737 * Don't try to run SYSUNINITs if we are unloaded due to a 738 * link error. 739 */ 740 if (file->flags & LINKER_FILE_LINKED) { 741 file->flags &= ~LINKER_FILE_LINKED; 742 linker_file_unregister_sysctls(file); 743 linker_file_sysuninit(file); 744 } 745 TAILQ_REMOVE(&linker_files, file, link); 746 747 if (file->deps) { 748 for (i = 0; i < file->ndeps; i++) 749 linker_file_unload(file->deps[i], flags); 750 free(file->deps, M_LINKER); 751 file->deps = NULL; 752 } 753 while ((cp = STAILQ_FIRST(&file->common)) != NULL) { 754 STAILQ_REMOVE_HEAD(&file->common, link); 755 free(cp, M_LINKER); 756 } 757 758 LINKER_UNLOAD(file); 759 760 EVENTHANDLER_INVOKE(kld_unload, file->filename, file->address, 761 file->size); 762 763 if (file->filename) { 764 free(file->filename, M_LINKER); 765 file->filename = NULL; 766 } 767 if (file->pathname) { 768 free(file->pathname, M_LINKER); 769 file->pathname = NULL; 770 } 771 kobj_delete((kobj_t) file, M_LINKER); 772 return (0); 773 } 774 775 int 776 linker_ctf_get(linker_file_t file, linker_ctf_t *lc) 777 { 778 return (LINKER_CTF_GET(file, lc)); 779 } 780 781 static int 782 linker_file_add_dependency(linker_file_t file, linker_file_t dep) 783 { 784 linker_file_t *newdeps; 785 786 sx_assert(&kld_sx, SA_XLOCKED); 787 file->deps = realloc(file->deps, (file->ndeps + 1) * sizeof(*newdeps), 788 M_LINKER, M_WAITOK | M_ZERO); 789 file->deps[file->ndeps] = dep; 790 file->ndeps++; 791 KLD_DPF(FILE, ("linker_file_add_dependency:" 792 " adding %s as dependency for %s\n", 793 dep->filename, file->filename)); 794 return (0); 795 } 796 797 /* 798 * Locate a linker set and its contents. This is a helper function to avoid 799 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **. 800 * This function is used in this file so we can avoid having lots of (void **) 801 * casts. 802 */ 803 int 804 linker_file_lookup_set(linker_file_t file, const char *name, 805 void *firstp, void *lastp, int *countp) 806 { 807 808 sx_assert(&kld_sx, SA_LOCKED); 809 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 810 } 811 812 /* 813 * List all functions in a file. 814 */ 815 int 816 linker_file_function_listall(linker_file_t lf, 817 linker_function_nameval_callback_t callback_func, void *arg) 818 { 819 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg)); 820 } 821 822 caddr_t 823 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 824 { 825 caddr_t sym; 826 int locked; 827 828 locked = sx_xlocked(&kld_sx); 829 if (!locked) 830 sx_xlock(&kld_sx); 831 sym = linker_file_lookup_symbol_internal(file, name, deps); 832 if (!locked) 833 sx_xunlock(&kld_sx); 834 return (sym); 835 } 836 837 static caddr_t 838 linker_file_lookup_symbol_internal(linker_file_t file, const char *name, 839 int deps) 840 { 841 c_linker_sym_t sym; 842 linker_symval_t symval; 843 caddr_t address; 844 size_t common_size = 0; 845 int i; 846 847 sx_assert(&kld_sx, SA_XLOCKED); 848 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 849 file, name, deps)); 850 851 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 852 LINKER_SYMBOL_VALUES(file, sym, &symval); 853 if (symval.value == 0) 854 /* 855 * For commons, first look them up in the 856 * dependencies and only allocate space if not found 857 * there. 858 */ 859 common_size = symval.size; 860 else { 861 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 862 ".value=%p\n", symval.value)); 863 return (symval.value); 864 } 865 } 866 if (deps) { 867 for (i = 0; i < file->ndeps; i++) { 868 address = linker_file_lookup_symbol_internal( 869 file->deps[i], name, 0); 870 if (address) { 871 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 872 " deps value=%p\n", address)); 873 return (address); 874 } 875 } 876 } 877 if (common_size > 0) { 878 /* 879 * This is a common symbol which was not found in the 880 * dependencies. We maintain a simple common symbol table in 881 * the file object. 882 */ 883 struct common_symbol *cp; 884 885 STAILQ_FOREACH(cp, &file->common, link) { 886 if (strcmp(cp->name, name) == 0) { 887 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 888 " old common value=%p\n", cp->address)); 889 return (cp->address); 890 } 891 } 892 /* 893 * Round the symbol size up to align. 894 */ 895 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 896 cp = malloc(sizeof(struct common_symbol) 897 + common_size + strlen(name) + 1, M_LINKER, 898 M_WAITOK | M_ZERO); 899 cp->address = (caddr_t)(cp + 1); 900 cp->name = cp->address + common_size; 901 strcpy(cp->name, name); 902 bzero(cp->address, common_size); 903 STAILQ_INSERT_TAIL(&file->common, cp, link); 904 905 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 906 " value=%p\n", cp->address)); 907 return (cp->address); 908 } 909 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 910 return (0); 911 } 912 913 /* 914 * Both DDB and stack(9) rely on the kernel linker to provide forward and 915 * backward lookup of symbols. However, DDB and sometimes stack(9) need to 916 * do this in a lockfree manner. We provide a set of internal helper 917 * routines to perform these operations without locks, and then wrappers that 918 * optionally lock. 919 * 920 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB. 921 */ 922 #ifdef DDB 923 static int 924 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym) 925 { 926 linker_file_t lf; 927 928 TAILQ_FOREACH(lf, &linker_files, link) { 929 if (LINKER_LOOKUP_DEBUG_SYMBOL(lf, symstr, sym) == 0) 930 return (0); 931 } 932 return (ENOENT); 933 } 934 #endif 935 936 static int 937 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 938 { 939 linker_file_t lf; 940 c_linker_sym_t best, es; 941 u_long diff, bestdiff, off; 942 943 best = 0; 944 off = (uintptr_t)value; 945 bestdiff = off; 946 TAILQ_FOREACH(lf, &linker_files, link) { 947 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 948 continue; 949 if (es != 0 && diff < bestdiff) { 950 best = es; 951 bestdiff = diff; 952 } 953 if (bestdiff == 0) 954 break; 955 } 956 if (best) { 957 *sym = best; 958 *diffp = bestdiff; 959 return (0); 960 } else { 961 *sym = 0; 962 *diffp = off; 963 return (ENOENT); 964 } 965 } 966 967 static int 968 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 969 { 970 linker_file_t lf; 971 972 TAILQ_FOREACH(lf, &linker_files, link) { 973 if (LINKER_DEBUG_SYMBOL_VALUES(lf, sym, symval) == 0) 974 return (0); 975 } 976 return (ENOENT); 977 } 978 979 static int 980 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen, 981 long *offset) 982 { 983 linker_symval_t symval; 984 c_linker_sym_t sym; 985 int error; 986 987 *offset = 0; 988 error = linker_debug_search_symbol(value, &sym, offset); 989 if (error) 990 return (error); 991 error = linker_debug_symbol_values(sym, &symval); 992 if (error) 993 return (error); 994 strlcpy(buf, symval.name, buflen); 995 return (0); 996 } 997 998 /* 999 * DDB Helpers. DDB has to look across multiple files with their own symbol 1000 * tables and string tables. 1001 * 1002 * Note that we do not obey list locking protocols here. We really don't need 1003 * DDB to hang because somebody's got the lock held. We'll take the chance 1004 * that the files list is inconsistent instead. 1005 */ 1006 #ifdef DDB 1007 int 1008 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 1009 { 1010 1011 return (linker_debug_lookup(symstr, sym)); 1012 } 1013 #endif 1014 1015 int 1016 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 1017 { 1018 1019 return (linker_debug_search_symbol(value, sym, diffp)); 1020 } 1021 1022 int 1023 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 1024 { 1025 1026 return (linker_debug_symbol_values(sym, symval)); 1027 } 1028 1029 int 1030 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1031 long *offset) 1032 { 1033 1034 return (linker_debug_search_symbol_name(value, buf, buflen, offset)); 1035 } 1036 1037 /* 1038 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do 1039 * obey locking protocols, and offer a significantly less complex interface. 1040 */ 1041 int 1042 linker_search_symbol_name_flags(caddr_t value, char *buf, u_int buflen, 1043 long *offset, int flags) 1044 { 1045 int error; 1046 1047 KASSERT((flags & (M_NOWAIT | M_WAITOK)) != 0 && 1048 (flags & (M_NOWAIT | M_WAITOK)) != (M_NOWAIT | M_WAITOK), 1049 ("%s: bad flags: 0x%x", __func__, flags)); 1050 1051 if (flags & M_NOWAIT) { 1052 if (!sx_try_slock(&kld_sx)) 1053 return (EWOULDBLOCK); 1054 } else 1055 sx_slock(&kld_sx); 1056 1057 error = linker_debug_search_symbol_name(value, buf, buflen, offset); 1058 sx_sunlock(&kld_sx); 1059 return (error); 1060 } 1061 1062 int 1063 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1064 long *offset) 1065 { 1066 1067 return (linker_search_symbol_name_flags(value, buf, buflen, offset, 1068 M_WAITOK)); 1069 } 1070 1071 int 1072 linker_kldload_busy(int flags) 1073 { 1074 int error; 1075 1076 MPASS((flags & ~(LINKER_UB_UNLOCK | LINKER_UB_LOCKED | 1077 LINKER_UB_PCATCH)) == 0); 1078 if ((flags & LINKER_UB_LOCKED) != 0) 1079 sx_assert(&kld_sx, SA_XLOCKED); 1080 1081 if ((flags & LINKER_UB_LOCKED) == 0) 1082 sx_xlock(&kld_sx); 1083 while (kld_busy > 0) { 1084 if (kld_busy_owner == curthread) 1085 break; 1086 error = sx_sleep(&kld_busy, &kld_sx, 1087 (flags & LINKER_UB_PCATCH) != 0 ? PCATCH : 0, 1088 "kldbusy", 0); 1089 if (error != 0) { 1090 if ((flags & LINKER_UB_UNLOCK) != 0) 1091 sx_xunlock(&kld_sx); 1092 return (error); 1093 } 1094 } 1095 kld_busy++; 1096 kld_busy_owner = curthread; 1097 if ((flags & LINKER_UB_UNLOCK) != 0) 1098 sx_xunlock(&kld_sx); 1099 return (0); 1100 } 1101 1102 void 1103 linker_kldload_unbusy(int flags) 1104 { 1105 MPASS((flags & ~LINKER_UB_LOCKED) == 0); 1106 if ((flags & LINKER_UB_LOCKED) != 0) 1107 sx_assert(&kld_sx, SA_XLOCKED); 1108 1109 if ((flags & LINKER_UB_LOCKED) == 0) 1110 sx_xlock(&kld_sx); 1111 MPASS(kld_busy > 0); 1112 if (kld_busy_owner != curthread) 1113 panic("linker_kldload_unbusy done by not owning thread %p", 1114 kld_busy_owner); 1115 kld_busy--; 1116 if (kld_busy == 0) { 1117 kld_busy_owner = NULL; 1118 wakeup(&kld_busy); 1119 } 1120 sx_xunlock(&kld_sx); 1121 } 1122 1123 /* 1124 * Syscalls. 1125 */ 1126 int 1127 kern_kldload(struct thread *td, const char *file, int *fileid) 1128 { 1129 const char *kldname, *modname; 1130 linker_file_t lf; 1131 int error; 1132 1133 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1134 return (error); 1135 1136 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 1137 return (error); 1138 1139 /* 1140 * If file does not contain a qualified name or any dot in it 1141 * (kldname.ko, or kldname.ver.ko) treat it as an interface 1142 * name. 1143 */ 1144 if (strchr(file, '/') || strchr(file, '.')) { 1145 kldname = file; 1146 modname = NULL; 1147 } else { 1148 kldname = NULL; 1149 modname = file; 1150 } 1151 1152 error = linker_kldload_busy(LINKER_UB_PCATCH); 1153 if (error != 0) { 1154 sx_xunlock(&kld_sx); 1155 return (error); 1156 } 1157 1158 /* 1159 * It is possible that kldloaded module will attach a new ifnet, 1160 * so vnet context must be set when this ocurs. 1161 */ 1162 CURVNET_SET(TD_TO_VNET(td)); 1163 1164 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 1165 CURVNET_RESTORE(); 1166 1167 if (error == 0) { 1168 lf->userrefs++; 1169 if (fileid != NULL) 1170 *fileid = lf->id; 1171 } 1172 linker_kldload_unbusy(LINKER_UB_LOCKED); 1173 return (error); 1174 } 1175 1176 int 1177 sys_kldload(struct thread *td, struct kldload_args *uap) 1178 { 1179 char *pathname = NULL; 1180 int error, fileid; 1181 1182 td->td_retval[0] = -1; 1183 1184 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1185 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 1186 if (error == 0) { 1187 error = kern_kldload(td, pathname, &fileid); 1188 if (error == 0) 1189 td->td_retval[0] = fileid; 1190 } 1191 free(pathname, M_TEMP); 1192 return (error); 1193 } 1194 1195 int 1196 kern_kldunload(struct thread *td, int fileid, int flags) 1197 { 1198 linker_file_t lf; 1199 int error = 0; 1200 1201 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1202 return (error); 1203 1204 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 1205 return (error); 1206 1207 error = linker_kldload_busy(LINKER_UB_PCATCH); 1208 if (error != 0) { 1209 sx_xunlock(&kld_sx); 1210 return (error); 1211 } 1212 1213 CURVNET_SET(TD_TO_VNET(td)); 1214 lf = linker_find_file_by_id(fileid); 1215 if (lf) { 1216 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 1217 1218 if (lf->userrefs == 0) { 1219 /* 1220 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 1221 */ 1222 printf("kldunload: attempt to unload file that was" 1223 " loaded by the kernel\n"); 1224 error = EBUSY; 1225 } else { 1226 lf->userrefs--; 1227 error = linker_file_unload(lf, flags); 1228 if (error) 1229 lf->userrefs++; 1230 } 1231 } else 1232 error = ENOENT; 1233 CURVNET_RESTORE(); 1234 linker_kldload_unbusy(LINKER_UB_LOCKED); 1235 return (error); 1236 } 1237 1238 int 1239 sys_kldunload(struct thread *td, struct kldunload_args *uap) 1240 { 1241 1242 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 1243 } 1244 1245 int 1246 sys_kldunloadf(struct thread *td, struct kldunloadf_args *uap) 1247 { 1248 1249 if (uap->flags != LINKER_UNLOAD_NORMAL && 1250 uap->flags != LINKER_UNLOAD_FORCE) 1251 return (EINVAL); 1252 return (kern_kldunload(td, uap->fileid, uap->flags)); 1253 } 1254 1255 int 1256 sys_kldfind(struct thread *td, struct kldfind_args *uap) 1257 { 1258 char *pathname; 1259 const char *filename; 1260 linker_file_t lf; 1261 int error; 1262 1263 #ifdef MAC 1264 error = mac_kld_check_stat(td->td_ucred); 1265 if (error) 1266 return (error); 1267 #endif 1268 1269 td->td_retval[0] = -1; 1270 1271 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1272 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1273 goto out; 1274 1275 filename = linker_basename(pathname); 1276 sx_xlock(&kld_sx); 1277 lf = linker_find_file_by_name(filename); 1278 if (lf) 1279 td->td_retval[0] = lf->id; 1280 else 1281 error = ENOENT; 1282 sx_xunlock(&kld_sx); 1283 out: 1284 free(pathname, M_TEMP); 1285 return (error); 1286 } 1287 1288 int 1289 sys_kldnext(struct thread *td, struct kldnext_args *uap) 1290 { 1291 linker_file_t lf; 1292 int error = 0; 1293 1294 #ifdef MAC 1295 error = mac_kld_check_stat(td->td_ucred); 1296 if (error) 1297 return (error); 1298 #endif 1299 1300 sx_xlock(&kld_sx); 1301 if (uap->fileid == 0) 1302 lf = TAILQ_FIRST(&linker_files); 1303 else { 1304 lf = linker_find_file_by_id(uap->fileid); 1305 if (lf == NULL) { 1306 error = ENOENT; 1307 goto out; 1308 } 1309 lf = TAILQ_NEXT(lf, link); 1310 } 1311 1312 /* Skip partially loaded files. */ 1313 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1314 lf = TAILQ_NEXT(lf, link); 1315 1316 if (lf) 1317 td->td_retval[0] = lf->id; 1318 else 1319 td->td_retval[0] = 0; 1320 out: 1321 sx_xunlock(&kld_sx); 1322 return (error); 1323 } 1324 1325 int 1326 sys_kldstat(struct thread *td, struct kldstat_args *uap) 1327 { 1328 struct kld_file_stat *stat; 1329 int error, version; 1330 1331 /* 1332 * Check the version of the user's structure. 1333 */ 1334 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) 1335 != 0) 1336 return (error); 1337 if (version != sizeof(struct kld_file_stat_1) && 1338 version != sizeof(struct kld_file_stat)) 1339 return (EINVAL); 1340 1341 stat = malloc(sizeof(*stat), M_TEMP, M_WAITOK | M_ZERO); 1342 error = kern_kldstat(td, uap->fileid, stat); 1343 if (error == 0) 1344 error = copyout(stat, uap->stat, version); 1345 free(stat, M_TEMP); 1346 return (error); 1347 } 1348 1349 int 1350 kern_kldstat(struct thread *td, int fileid, struct kld_file_stat *stat) 1351 { 1352 linker_file_t lf; 1353 int namelen; 1354 #ifdef MAC 1355 int error; 1356 1357 error = mac_kld_check_stat(td->td_ucred); 1358 if (error) 1359 return (error); 1360 #endif 1361 1362 sx_xlock(&kld_sx); 1363 lf = linker_find_file_by_id(fileid); 1364 if (lf == NULL) { 1365 sx_xunlock(&kld_sx); 1366 return (ENOENT); 1367 } 1368 1369 /* Version 1 fields: */ 1370 namelen = strlen(lf->filename) + 1; 1371 if (namelen > sizeof(stat->name)) 1372 namelen = sizeof(stat->name); 1373 bcopy(lf->filename, &stat->name[0], namelen); 1374 stat->refs = lf->refs; 1375 stat->id = lf->id; 1376 stat->address = lf->address; 1377 stat->size = lf->size; 1378 /* Version 2 fields: */ 1379 namelen = strlen(lf->pathname) + 1; 1380 if (namelen > sizeof(stat->pathname)) 1381 namelen = sizeof(stat->pathname); 1382 bcopy(lf->pathname, &stat->pathname[0], namelen); 1383 sx_xunlock(&kld_sx); 1384 1385 td->td_retval[0] = 0; 1386 return (0); 1387 } 1388 1389 #ifdef DDB 1390 DB_COMMAND_FLAGS(kldstat, db_kldstat, DB_CMD_MEMSAFE) 1391 { 1392 linker_file_t lf; 1393 1394 #define POINTER_WIDTH ((int)(sizeof(void *) * 2 + 2)) 1395 db_printf("Id Refs Address%*c Size Name\n", POINTER_WIDTH - 7, ' '); 1396 #undef POINTER_WIDTH 1397 TAILQ_FOREACH(lf, &linker_files, link) { 1398 if (db_pager_quit) 1399 return; 1400 db_printf("%2d %4d %p %-8zx %s\n", lf->id, lf->refs, 1401 lf->address, lf->size, lf->filename); 1402 } 1403 } 1404 #endif /* DDB */ 1405 1406 int 1407 sys_kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1408 { 1409 linker_file_t lf; 1410 module_t mp; 1411 int error = 0; 1412 1413 #ifdef MAC 1414 error = mac_kld_check_stat(td->td_ucred); 1415 if (error) 1416 return (error); 1417 #endif 1418 1419 sx_xlock(&kld_sx); 1420 lf = linker_find_file_by_id(uap->fileid); 1421 if (lf) { 1422 MOD_SLOCK; 1423 mp = TAILQ_FIRST(&lf->modules); 1424 if (mp != NULL) 1425 td->td_retval[0] = module_getid(mp); 1426 else 1427 td->td_retval[0] = 0; 1428 MOD_SUNLOCK; 1429 } else 1430 error = ENOENT; 1431 sx_xunlock(&kld_sx); 1432 return (error); 1433 } 1434 1435 int 1436 sys_kldsym(struct thread *td, struct kldsym_args *uap) 1437 { 1438 char *symstr = NULL; 1439 c_linker_sym_t sym; 1440 linker_symval_t symval; 1441 linker_file_t lf; 1442 struct kld_sym_lookup lookup; 1443 int error = 0; 1444 1445 #ifdef MAC 1446 error = mac_kld_check_stat(td->td_ucred); 1447 if (error) 1448 return (error); 1449 #endif 1450 1451 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1452 return (error); 1453 if (lookup.version != sizeof(lookup) || 1454 uap->cmd != KLDSYM_LOOKUP) 1455 return (EINVAL); 1456 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1457 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1458 goto out; 1459 sx_xlock(&kld_sx); 1460 if (uap->fileid != 0) { 1461 lf = linker_find_file_by_id(uap->fileid); 1462 if (lf == NULL) 1463 error = ENOENT; 1464 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1465 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1466 lookup.symvalue = (uintptr_t) symval.value; 1467 lookup.symsize = symval.size; 1468 error = copyout(&lookup, uap->data, sizeof(lookup)); 1469 } else 1470 error = ENOENT; 1471 } else { 1472 TAILQ_FOREACH(lf, &linker_files, link) { 1473 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1474 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1475 lookup.symvalue = (uintptr_t)symval.value; 1476 lookup.symsize = symval.size; 1477 error = copyout(&lookup, uap->data, 1478 sizeof(lookup)); 1479 break; 1480 } 1481 } 1482 if (lf == NULL) 1483 error = ENOENT; 1484 } 1485 sx_xunlock(&kld_sx); 1486 out: 1487 free(symstr, M_TEMP); 1488 return (error); 1489 } 1490 1491 /* 1492 * Preloaded module support 1493 */ 1494 1495 static modlist_t 1496 modlist_lookup(const char *name, int ver) 1497 { 1498 modlist_t mod; 1499 1500 TAILQ_FOREACH(mod, &found_modules, link) { 1501 if (strcmp(mod->name, name) == 0 && 1502 (ver == 0 || mod->version == ver)) 1503 return (mod); 1504 } 1505 return (NULL); 1506 } 1507 1508 static modlist_t 1509 modlist_lookup2(const char *name, const struct mod_depend *verinfo) 1510 { 1511 modlist_t mod, bestmod; 1512 int ver; 1513 1514 if (verinfo == NULL) 1515 return (modlist_lookup(name, 0)); 1516 bestmod = NULL; 1517 TAILQ_FOREACH(mod, &found_modules, link) { 1518 if (strcmp(mod->name, name) != 0) 1519 continue; 1520 ver = mod->version; 1521 if (ver == verinfo->md_ver_preferred) 1522 return (mod); 1523 if (ver >= verinfo->md_ver_minimum && 1524 ver <= verinfo->md_ver_maximum && 1525 (bestmod == NULL || ver > bestmod->version)) 1526 bestmod = mod; 1527 } 1528 return (bestmod); 1529 } 1530 1531 static modlist_t 1532 modlist_newmodule(const char *modname, int version, linker_file_t container) 1533 { 1534 modlist_t mod; 1535 1536 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1537 if (mod == NULL) 1538 panic("no memory for module list"); 1539 mod->container = container; 1540 mod->name = modname; 1541 mod->version = version; 1542 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1543 return (mod); 1544 } 1545 1546 static void 1547 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1548 struct mod_metadata **stop, int preload) 1549 { 1550 struct mod_metadata *mp, **mdp; 1551 const char *modname; 1552 int ver; 1553 1554 for (mdp = start; mdp < stop; mdp++) { 1555 mp = *mdp; 1556 if (mp->md_type != MDT_VERSION) 1557 continue; 1558 modname = mp->md_cval; 1559 ver = ((const struct mod_version *)mp->md_data)->mv_version; 1560 if (modlist_lookup(modname, ver) != NULL) { 1561 printf("module %s already present!\n", modname); 1562 /* XXX what can we do? this is a build error. :-( */ 1563 continue; 1564 } 1565 modlist_newmodule(modname, ver, lf); 1566 } 1567 } 1568 1569 static void 1570 linker_preload(void *arg) 1571 { 1572 caddr_t modptr; 1573 const char *modname, *nmodname; 1574 char *modtype; 1575 linker_file_t lf, nlf; 1576 linker_class_t lc; 1577 int error; 1578 linker_file_list_t loaded_files; 1579 linker_file_list_t depended_files; 1580 struct mod_metadata *mp, *nmp; 1581 struct mod_metadata **start, **stop, **mdp, **nmdp; 1582 const struct mod_depend *verinfo; 1583 int nver; 1584 int resolves; 1585 modlist_t mod; 1586 struct sysinit **si_start, **si_stop; 1587 1588 TAILQ_INIT(&loaded_files); 1589 TAILQ_INIT(&depended_files); 1590 TAILQ_INIT(&found_modules); 1591 error = 0; 1592 1593 modptr = NULL; 1594 sx_xlock(&kld_sx); 1595 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1596 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1597 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1598 if (modname == NULL) { 1599 printf("Preloaded module at %p does not have a" 1600 " name!\n", modptr); 1601 continue; 1602 } 1603 if (modtype == NULL) { 1604 printf("Preloaded module at %p does not have a type!\n", 1605 modptr); 1606 continue; 1607 } 1608 if (bootverbose) 1609 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1610 modptr); 1611 lf = NULL; 1612 TAILQ_FOREACH(lc, &classes, link) { 1613 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1614 if (!error) 1615 break; 1616 lf = NULL; 1617 } 1618 if (lf) 1619 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1620 } 1621 1622 /* 1623 * First get a list of stuff in the kernel. 1624 */ 1625 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1626 &stop, NULL) == 0) 1627 linker_addmodules(linker_kernel_file, start, stop, 1); 1628 1629 /* 1630 * This is a once-off kinky bubble sort to resolve relocation 1631 * dependency requirements. 1632 */ 1633 restart: 1634 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1635 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1636 &stop, NULL); 1637 /* 1638 * First, look to see if we would successfully link with this 1639 * stuff. 1640 */ 1641 resolves = 1; /* unless we know otherwise */ 1642 if (!error) { 1643 for (mdp = start; mdp < stop; mdp++) { 1644 mp = *mdp; 1645 if (mp->md_type != MDT_DEPEND) 1646 continue; 1647 modname = mp->md_cval; 1648 verinfo = mp->md_data; 1649 for (nmdp = start; nmdp < stop; nmdp++) { 1650 nmp = *nmdp; 1651 if (nmp->md_type != MDT_VERSION) 1652 continue; 1653 nmodname = nmp->md_cval; 1654 if (strcmp(modname, nmodname) == 0) 1655 break; 1656 } 1657 if (nmdp < stop) /* it's a self reference */ 1658 continue; 1659 1660 /* 1661 * ok, the module isn't here yet, we 1662 * are not finished 1663 */ 1664 if (modlist_lookup2(modname, verinfo) == NULL) 1665 resolves = 0; 1666 } 1667 } 1668 /* 1669 * OK, if we found our modules, we can link. So, "provide" 1670 * the modules inside and add it to the end of the link order 1671 * list. 1672 */ 1673 if (resolves) { 1674 if (!error) { 1675 for (mdp = start; mdp < stop; mdp++) { 1676 mp = *mdp; 1677 if (mp->md_type != MDT_VERSION) 1678 continue; 1679 modname = mp->md_cval; 1680 nver = ((const struct mod_version *) 1681 mp->md_data)->mv_version; 1682 if (modlist_lookup(modname, 1683 nver) != NULL) { 1684 printf("module %s already" 1685 " present!\n", modname); 1686 TAILQ_REMOVE(&loaded_files, 1687 lf, loaded); 1688 linker_file_unload(lf, 1689 LINKER_UNLOAD_FORCE); 1690 /* we changed tailq next ptr */ 1691 goto restart; 1692 } 1693 modlist_newmodule(modname, nver, lf); 1694 } 1695 } 1696 TAILQ_REMOVE(&loaded_files, lf, loaded); 1697 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1698 /* 1699 * Since we provided modules, we need to restart the 1700 * sort so that the previous files that depend on us 1701 * have a chance. Also, we've busted the tailq next 1702 * pointer with the REMOVE. 1703 */ 1704 goto restart; 1705 } 1706 } 1707 1708 /* 1709 * At this point, we check to see what could not be resolved.. 1710 */ 1711 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1712 TAILQ_REMOVE(&loaded_files, lf, loaded); 1713 printf("KLD file %s is missing dependencies\n", lf->filename); 1714 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1715 } 1716 1717 /* 1718 * We made it. Finish off the linking in the order we determined. 1719 */ 1720 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1721 if (linker_kernel_file) { 1722 linker_kernel_file->refs++; 1723 error = linker_file_add_dependency(lf, 1724 linker_kernel_file); 1725 if (error) 1726 panic("cannot add dependency"); 1727 } 1728 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1729 &stop, NULL); 1730 if (!error) { 1731 for (mdp = start; mdp < stop; mdp++) { 1732 mp = *mdp; 1733 if (mp->md_type != MDT_DEPEND) 1734 continue; 1735 modname = mp->md_cval; 1736 verinfo = mp->md_data; 1737 mod = modlist_lookup2(modname, verinfo); 1738 if (mod == NULL) { 1739 printf("KLD file %s - cannot find " 1740 "dependency \"%s\"\n", 1741 lf->filename, modname); 1742 goto fail; 1743 } 1744 /* Don't count self-dependencies */ 1745 if (lf == mod->container) 1746 continue; 1747 mod->container->refs++; 1748 error = linker_file_add_dependency(lf, 1749 mod->container); 1750 if (error) 1751 panic("cannot add dependency"); 1752 } 1753 } 1754 /* 1755 * Now do relocation etc using the symbol search paths 1756 * established by the dependencies 1757 */ 1758 error = LINKER_LINK_PRELOAD_FINISH(lf); 1759 if (error) { 1760 printf("KLD file %s - could not finalize loading\n", 1761 lf->filename); 1762 goto fail; 1763 } 1764 linker_file_register_modules(lf); 1765 if (!TAILQ_EMPTY(&lf->modules)) 1766 lf->flags |= LINKER_FILE_MODULES; 1767 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1768 &si_stop, NULL) == 0) 1769 sysinit_add(si_start, si_stop); 1770 linker_file_register_sysctls(lf, true); 1771 lf->flags |= LINKER_FILE_LINKED; 1772 continue; 1773 fail: 1774 TAILQ_REMOVE(&depended_files, lf, loaded); 1775 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1776 } 1777 sx_xunlock(&kld_sx); 1778 /* woohoo! we made it! */ 1779 } 1780 1781 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, NULL); 1782 1783 /* 1784 * Handle preload files that failed to load any modules. 1785 */ 1786 static void 1787 linker_preload_finish(void *arg) 1788 { 1789 linker_file_t lf, nlf; 1790 1791 sx_xlock(&kld_sx); 1792 TAILQ_FOREACH_SAFE(lf, &linker_files, link, nlf) { 1793 /* 1794 * If all of the modules in this file failed to load, unload 1795 * the file and return an error of ENOEXEC. (Parity with 1796 * linker_load_file.) 1797 */ 1798 if ((lf->flags & LINKER_FILE_MODULES) != 0 && 1799 TAILQ_EMPTY(&lf->modules)) { 1800 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1801 continue; 1802 } 1803 1804 lf->flags &= ~LINKER_FILE_MODULES; 1805 lf->userrefs++; /* so we can (try to) kldunload it */ 1806 } 1807 sx_xunlock(&kld_sx); 1808 } 1809 1810 /* 1811 * Attempt to run after all DECLARE_MODULE SYSINITs. Unfortunately they can be 1812 * scheduled at any subsystem and order, so run this as late as possible. init 1813 * becomes runnable in SI_SUB_KTHREAD_INIT, so go slightly before that. 1814 */ 1815 SYSINIT(preload_finish, SI_SUB_KTHREAD_INIT - 100, SI_ORDER_MIDDLE, 1816 linker_preload_finish, NULL); 1817 1818 /* 1819 * Search for a not-loaded module by name. 1820 * 1821 * Modules may be found in the following locations: 1822 * 1823 * - preloaded (result is just the module name) - on disk (result is full path 1824 * to module) 1825 * 1826 * If the module name is qualified in any way (contains path, etc.) the we 1827 * simply return a copy of it. 1828 * 1829 * The search path can be manipulated via sysctl. Note that we use the ';' 1830 * character as a separator to be consistent with the bootloader. 1831 */ 1832 1833 static char linker_hintfile[] = "linker.hints"; 1834 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1835 1836 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RWTUN, linker_path, 1837 sizeof(linker_path), "module load search path"); 1838 1839 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1840 1841 static const char * const linker_ext_list[] = { 1842 "", 1843 ".ko", 1844 NULL 1845 }; 1846 1847 /* 1848 * Check if file actually exists either with or without extension listed in 1849 * the linker_ext_list. (probably should be generic for the rest of the 1850 * kernel) 1851 */ 1852 static char * 1853 linker_lookup_file(const char *path, int pathlen, const char *name, 1854 int namelen, struct vattr *vap) 1855 { 1856 struct nameidata nd; 1857 struct thread *td = curthread; /* XXX */ 1858 const char * const *cpp, *sep; 1859 char *result; 1860 int error, len, extlen, reclen, flags; 1861 enum vtype type; 1862 1863 extlen = 0; 1864 for (cpp = linker_ext_list; *cpp; cpp++) { 1865 len = strlen(*cpp); 1866 if (len > extlen) 1867 extlen = len; 1868 } 1869 extlen++; /* trailing '\0' */ 1870 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1871 1872 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1873 result = malloc(reclen, M_LINKER, M_WAITOK); 1874 for (cpp = linker_ext_list; *cpp; cpp++) { 1875 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1876 namelen, name, *cpp); 1877 /* 1878 * Attempt to open the file, and return the path if 1879 * we succeed and it's a regular file. 1880 */ 1881 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result); 1882 flags = FREAD; 1883 error = vn_open(&nd, &flags, 0, NULL); 1884 if (error == 0) { 1885 NDFREE_PNBUF(&nd); 1886 type = nd.ni_vp->v_type; 1887 if (vap) 1888 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred); 1889 VOP_UNLOCK(nd.ni_vp); 1890 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1891 if (type == VREG) 1892 return (result); 1893 } 1894 } 1895 free(result, M_LINKER); 1896 return (NULL); 1897 } 1898 1899 #define INT_ALIGN(base, ptr) ptr = \ 1900 (base) + roundup2((ptr) - (base), sizeof(int)) 1901 1902 /* 1903 * Lookup KLD which contains requested module in the "linker.hints" file. If 1904 * version specification is available, then try to find the best KLD. 1905 * Otherwise just find the latest one. 1906 */ 1907 static char * 1908 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1909 int modnamelen, const struct mod_depend *verinfo) 1910 { 1911 struct thread *td = curthread; /* XXX */ 1912 struct ucred *cred = td ? td->td_ucred : NULL; 1913 struct nameidata nd; 1914 struct vattr vattr, mattr; 1915 const char *best, *sep; 1916 u_char *hints = NULL; 1917 u_char *cp, *recptr, *bufend, *result, *pathbuf; 1918 int error, ival, bestver, *intp, found, flags, clen, blen; 1919 ssize_t reclen; 1920 1921 result = NULL; 1922 bestver = found = 0; 1923 1924 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1925 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1926 strlen(sep) + 1; 1927 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1928 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1929 linker_hintfile); 1930 1931 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf); 1932 flags = FREAD; 1933 error = vn_open(&nd, &flags, 0, NULL); 1934 if (error) 1935 goto bad; 1936 NDFREE_PNBUF(&nd); 1937 if (nd.ni_vp->v_type != VREG) 1938 goto bad; 1939 best = cp = NULL; 1940 error = VOP_GETATTR(nd.ni_vp, &vattr, cred); 1941 if (error) 1942 goto bad; 1943 /* 1944 * XXX: we need to limit this number to some reasonable value 1945 */ 1946 if (vattr.va_size > LINKER_HINTS_MAX) { 1947 printf("linker.hints file too large %ld\n", (long)vattr.va_size); 1948 goto bad; 1949 } 1950 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1951 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1952 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1953 if (error) 1954 goto bad; 1955 VOP_UNLOCK(nd.ni_vp); 1956 vn_close(nd.ni_vp, FREAD, cred, td); 1957 nd.ni_vp = NULL; 1958 if (reclen != 0) { 1959 printf("can't read %zd\n", reclen); 1960 goto bad; 1961 } 1962 intp = (int *)hints; 1963 ival = *intp++; 1964 if (ival != LINKER_HINTS_VERSION) { 1965 printf("linker.hints file version mismatch %d\n", ival); 1966 goto bad; 1967 } 1968 bufend = hints + vattr.va_size; 1969 recptr = (u_char *)intp; 1970 clen = blen = 0; 1971 while (recptr < bufend && !found) { 1972 intp = (int *)recptr; 1973 reclen = *intp++; 1974 ival = *intp++; 1975 cp = (char *)intp; 1976 switch (ival) { 1977 case MDT_VERSION: 1978 clen = *cp++; 1979 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1980 break; 1981 cp += clen; 1982 INT_ALIGN(hints, cp); 1983 ival = *(int *)cp; 1984 cp += sizeof(int); 1985 clen = *cp++; 1986 if (verinfo == NULL || 1987 ival == verinfo->md_ver_preferred) { 1988 found = 1; 1989 break; 1990 } 1991 if (ival >= verinfo->md_ver_minimum && 1992 ival <= verinfo->md_ver_maximum && 1993 ival > bestver) { 1994 bestver = ival; 1995 best = cp; 1996 blen = clen; 1997 } 1998 break; 1999 default: 2000 break; 2001 } 2002 recptr += reclen + sizeof(int); 2003 } 2004 /* 2005 * Finally check if KLD is in the place 2006 */ 2007 if (found) 2008 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 2009 else if (best) 2010 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 2011 2012 /* 2013 * KLD is newer than hints file. What we should do now? 2014 */ 2015 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 2016 printf("warning: KLD '%s' is newer than the linker.hints" 2017 " file\n", result); 2018 bad: 2019 free(pathbuf, M_LINKER); 2020 if (hints) 2021 free(hints, M_TEMP); 2022 if (nd.ni_vp != NULL) { 2023 VOP_UNLOCK(nd.ni_vp); 2024 vn_close(nd.ni_vp, FREAD, cred, td); 2025 } 2026 /* 2027 * If nothing found or hints is absent - fallback to the old 2028 * way by using "kldname[.ko]" as module name. 2029 */ 2030 if (!found && !bestver && result == NULL) 2031 result = linker_lookup_file(path, pathlen, modname, 2032 modnamelen, NULL); 2033 return (result); 2034 } 2035 2036 /* 2037 * Lookup KLD which contains requested module in the all directories. 2038 */ 2039 static char * 2040 linker_search_module(const char *modname, int modnamelen, 2041 const struct mod_depend *verinfo) 2042 { 2043 char *cp, *ep, *result; 2044 2045 /* 2046 * traverse the linker path 2047 */ 2048 for (cp = linker_path; *cp; cp = ep + 1) { 2049 /* find the end of this component */ 2050 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 2051 result = linker_hints_lookup(cp, ep - cp, modname, 2052 modnamelen, verinfo); 2053 if (result != NULL) 2054 return (result); 2055 if (*ep == 0) 2056 break; 2057 } 2058 return (NULL); 2059 } 2060 2061 /* 2062 * Search for module in all directories listed in the linker_path. 2063 */ 2064 static char * 2065 linker_search_kld(const char *name) 2066 { 2067 char *cp, *ep, *result; 2068 int len; 2069 2070 /* qualified at all? */ 2071 if (strchr(name, '/')) 2072 return (strdup(name, M_LINKER)); 2073 2074 /* traverse the linker path */ 2075 len = strlen(name); 2076 for (ep = linker_path; *ep; ep++) { 2077 cp = ep; 2078 /* find the end of this component */ 2079 for (; *ep != 0 && *ep != ';'; ep++); 2080 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 2081 if (result != NULL) 2082 return (result); 2083 } 2084 return (NULL); 2085 } 2086 2087 static const char * 2088 linker_basename(const char *path) 2089 { 2090 const char *filename; 2091 2092 filename = strrchr(path, '/'); 2093 if (filename == NULL) 2094 return path; 2095 if (filename[1]) 2096 filename++; 2097 return (filename); 2098 } 2099 2100 #ifdef HWPMC_HOOKS 2101 /* 2102 * Inform hwpmc about the set of kernel modules currently loaded. 2103 */ 2104 void * 2105 linker_hwpmc_list_objects(void) 2106 { 2107 linker_file_t lf; 2108 struct pmckern_map_in *kobase; 2109 int i, nmappings; 2110 2111 nmappings = 0; 2112 sx_slock(&kld_sx); 2113 TAILQ_FOREACH(lf, &linker_files, link) 2114 nmappings++; 2115 2116 /* Allocate nmappings + 1 entries. */ 2117 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in), 2118 M_LINKER, M_WAITOK | M_ZERO); 2119 i = 0; 2120 TAILQ_FOREACH(lf, &linker_files, link) { 2121 /* Save the info for this linker file. */ 2122 kobase[i].pm_file = lf->filename; 2123 kobase[i].pm_address = (uintptr_t)lf->address; 2124 i++; 2125 } 2126 sx_sunlock(&kld_sx); 2127 2128 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?")); 2129 2130 /* The last entry of the malloced area comprises of all zeros. */ 2131 KASSERT(kobase[i].pm_file == NULL, 2132 ("linker_hwpmc_list_objects: last object not NULL")); 2133 2134 return ((void *)kobase); 2135 } 2136 #endif 2137 2138 /* check if root file system is not mounted */ 2139 static bool 2140 linker_root_mounted(void) 2141 { 2142 struct pwd *pwd; 2143 bool ret; 2144 2145 if (rootvnode == NULL) 2146 return (false); 2147 2148 pwd = pwd_hold(curthread); 2149 ret = pwd->pwd_rdir != NULL; 2150 pwd_drop(pwd); 2151 return (ret); 2152 } 2153 2154 /* 2155 * Find a file which contains given module and load it, if "parent" is not 2156 * NULL, register a reference to it. 2157 */ 2158 static int 2159 linker_load_module(const char *kldname, const char *modname, 2160 struct linker_file *parent, const struct mod_depend *verinfo, 2161 struct linker_file **lfpp) 2162 { 2163 linker_file_t lfdep; 2164 const char *filename; 2165 char *pathname; 2166 int error; 2167 2168 sx_assert(&kld_sx, SA_XLOCKED); 2169 if (modname == NULL) { 2170 /* 2171 * We have to load KLD 2172 */ 2173 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 2174 " is not NULL")); 2175 if (!linker_root_mounted()) 2176 return (ENXIO); 2177 pathname = linker_search_kld(kldname); 2178 } else { 2179 if (modlist_lookup2(modname, verinfo) != NULL) 2180 return (EEXIST); 2181 if (!linker_root_mounted()) 2182 return (ENXIO); 2183 if (kldname != NULL) 2184 pathname = strdup(kldname, M_LINKER); 2185 else 2186 /* 2187 * Need to find a KLD with required module 2188 */ 2189 pathname = linker_search_module(modname, 2190 strlen(modname), verinfo); 2191 } 2192 if (pathname == NULL) 2193 return (ENOENT); 2194 2195 /* 2196 * Can't load more than one file with the same basename XXX: 2197 * Actually it should be possible to have multiple KLDs with 2198 * the same basename but different path because they can 2199 * provide different versions of the same modules. 2200 */ 2201 filename = linker_basename(pathname); 2202 if (linker_find_file_by_name(filename)) 2203 error = EEXIST; 2204 else do { 2205 error = linker_load_file(pathname, &lfdep); 2206 if (error) 2207 break; 2208 if (modname && verinfo && 2209 modlist_lookup2(modname, verinfo) == NULL) { 2210 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 2211 error = ENOENT; 2212 break; 2213 } 2214 if (parent) { 2215 error = linker_file_add_dependency(parent, lfdep); 2216 if (error) 2217 break; 2218 } 2219 if (lfpp) 2220 *lfpp = lfdep; 2221 } while (0); 2222 free(pathname, M_LINKER); 2223 return (error); 2224 } 2225 2226 /* 2227 * This routine is responsible for finding dependencies of userland initiated 2228 * kldload(2)'s of files. 2229 */ 2230 int 2231 linker_load_dependencies(linker_file_t lf) 2232 { 2233 linker_file_t lfdep; 2234 struct mod_metadata **start, **stop, **mdp, **nmdp; 2235 struct mod_metadata *mp, *nmp; 2236 const struct mod_depend *verinfo; 2237 modlist_t mod; 2238 const char *modname, *nmodname; 2239 int ver, error = 0; 2240 2241 /* 2242 * All files are dependent on /kernel. 2243 */ 2244 sx_assert(&kld_sx, SA_XLOCKED); 2245 if (linker_kernel_file) { 2246 linker_kernel_file->refs++; 2247 error = linker_file_add_dependency(lf, linker_kernel_file); 2248 if (error) 2249 return (error); 2250 } 2251 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 2252 NULL) != 0) 2253 return (0); 2254 for (mdp = start; mdp < stop; mdp++) { 2255 mp = *mdp; 2256 if (mp->md_type != MDT_VERSION) 2257 continue; 2258 modname = mp->md_cval; 2259 ver = ((const struct mod_version *)mp->md_data)->mv_version; 2260 mod = modlist_lookup(modname, ver); 2261 if (mod != NULL) { 2262 printf("interface %s.%d already present in the KLD" 2263 " '%s'!\n", modname, ver, 2264 mod->container->filename); 2265 return (EEXIST); 2266 } 2267 } 2268 2269 for (mdp = start; mdp < stop; mdp++) { 2270 mp = *mdp; 2271 if (mp->md_type != MDT_DEPEND) 2272 continue; 2273 modname = mp->md_cval; 2274 verinfo = mp->md_data; 2275 nmodname = NULL; 2276 for (nmdp = start; nmdp < stop; nmdp++) { 2277 nmp = *nmdp; 2278 if (nmp->md_type != MDT_VERSION) 2279 continue; 2280 nmodname = nmp->md_cval; 2281 if (strcmp(modname, nmodname) == 0) 2282 break; 2283 } 2284 if (nmdp < stop)/* early exit, it's a self reference */ 2285 continue; 2286 mod = modlist_lookup2(modname, verinfo); 2287 if (mod) { /* woohoo, it's loaded already */ 2288 lfdep = mod->container; 2289 lfdep->refs++; 2290 error = linker_file_add_dependency(lf, lfdep); 2291 if (error) 2292 break; 2293 continue; 2294 } 2295 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 2296 if (error) { 2297 printf("KLD %s: depends on %s - not available or" 2298 " version mismatch\n", lf->filename, modname); 2299 break; 2300 } 2301 } 2302 2303 if (error) 2304 return (error); 2305 linker_addmodules(lf, start, stop, 0); 2306 return (error); 2307 } 2308 2309 static int 2310 sysctl_kern_function_list_iterate(const char *name, void *opaque) 2311 { 2312 struct sysctl_req *req; 2313 2314 req = opaque; 2315 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 2316 } 2317 2318 /* 2319 * Export a nul-separated, double-nul-terminated list of all function names 2320 * in the kernel. 2321 */ 2322 static int 2323 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 2324 { 2325 linker_file_t lf; 2326 int error; 2327 2328 #ifdef MAC 2329 error = mac_kld_check_stat(req->td->td_ucred); 2330 if (error) 2331 return (error); 2332 #endif 2333 error = sysctl_wire_old_buffer(req, 0); 2334 if (error != 0) 2335 return (error); 2336 sx_xlock(&kld_sx); 2337 TAILQ_FOREACH(lf, &linker_files, link) { 2338 error = LINKER_EACH_FUNCTION_NAME(lf, 2339 sysctl_kern_function_list_iterate, req); 2340 if (error) { 2341 sx_xunlock(&kld_sx); 2342 return (error); 2343 } 2344 } 2345 sx_xunlock(&kld_sx); 2346 return (SYSCTL_OUT(req, "", 1)); 2347 } 2348 2349 SYSCTL_PROC(_kern, OID_AUTO, function_list, 2350 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 2351 sysctl_kern_function_list, "", 2352 "kernel function list");
Cache object: ba6d27694c037177957d34e1a07fb393
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