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 void 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 /* 332 * Invoke the LINKER_CTF_GET implementation for this file. Existing 333 * implementations will load CTF info from the filesystem upon the first call 334 * and cache it in the kernel thereafter. 335 */ 336 static void 337 linker_ctf_load_file(linker_file_t file) 338 { 339 linker_ctf_t lc; 340 int error; 341 342 error = linker_ctf_get(file, &lc); 343 if (error == 0) 344 return; 345 if (bootverbose) { 346 printf("failed to load CTF for %s: %d\n", file->filename, 347 error); 348 } 349 } 350 351 static void 352 linker_file_enable_sysctls(linker_file_t lf) 353 { 354 struct sysctl_oid **start, **stop, **oidp; 355 356 KLD_DPF(FILE, 357 ("linker_file_enable_sysctls: enable SYSCTLs for %s\n", 358 lf->filename)); 359 360 sx_assert(&kld_sx, SA_XLOCKED); 361 362 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 363 return; 364 365 sx_xunlock(&kld_sx); 366 sysctl_wlock(); 367 for (oidp = start; oidp < stop; oidp++) 368 sysctl_enable_oid(*oidp); 369 sysctl_wunlock(); 370 sx_xlock(&kld_sx); 371 } 372 373 static void 374 linker_file_unregister_sysctls(linker_file_t lf) 375 { 376 struct sysctl_oid **start, **stop, **oidp; 377 378 KLD_DPF(FILE, ("linker_file_unregister_sysctls: unregistering SYSCTLs" 379 " for %s\n", lf->filename)); 380 381 sx_assert(&kld_sx, SA_XLOCKED); 382 383 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 384 return; 385 386 sx_xunlock(&kld_sx); 387 sysctl_wlock(); 388 for (oidp = start; oidp < stop; oidp++) 389 sysctl_unregister_oid(*oidp); 390 sysctl_wunlock(); 391 sx_xlock(&kld_sx); 392 } 393 394 static int 395 linker_file_register_modules(linker_file_t lf) 396 { 397 struct mod_metadata **start, **stop, **mdp; 398 const moduledata_t *moddata; 399 int first_error, error; 400 401 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 402 " in %s\n", lf->filename)); 403 404 sx_assert(&kld_sx, SA_XLOCKED); 405 406 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL) != 0) { 407 /* 408 * This fallback should be unnecessary, but if we get booted 409 * from boot2 instead of loader and we are missing our 410 * metadata then we have to try the best we can. 411 */ 412 if (lf == linker_kernel_file) { 413 start = SET_BEGIN(modmetadata_set); 414 stop = SET_LIMIT(modmetadata_set); 415 } else 416 return (0); 417 } 418 first_error = 0; 419 for (mdp = start; mdp < stop; mdp++) { 420 if ((*mdp)->md_type != MDT_MODULE) 421 continue; 422 moddata = (*mdp)->md_data; 423 KLD_DPF(FILE, ("Registering module %s in %s\n", 424 moddata->name, lf->filename)); 425 error = module_register(moddata, lf); 426 if (error) { 427 printf("Module %s failed to register: %d\n", 428 moddata->name, error); 429 if (first_error == 0) 430 first_error = error; 431 } 432 } 433 return (first_error); 434 } 435 436 static void 437 linker_init_kernel_modules(void) 438 { 439 440 sx_xlock(&kld_sx); 441 linker_file_register_modules(linker_kernel_file); 442 sx_xunlock(&kld_sx); 443 } 444 445 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 446 NULL); 447 448 static int 449 linker_load_file(const char *filename, linker_file_t *result) 450 { 451 linker_class_t lc; 452 linker_file_t lf; 453 int foundfile, error, modules; 454 455 /* Refuse to load modules if securelevel raised */ 456 if (prison0.pr_securelevel > 0) 457 return (EPERM); 458 459 sx_assert(&kld_sx, SA_XLOCKED); 460 lf = linker_find_file_by_name(filename); 461 if (lf) { 462 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 463 " incrementing refs\n", filename)); 464 *result = lf; 465 lf->refs++; 466 return (0); 467 } 468 foundfile = 0; 469 error = 0; 470 471 /* 472 * We do not need to protect (lock) classes here because there is 473 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 474 * and there is no class deregistration mechanism at this time. 475 */ 476 TAILQ_FOREACH(lc, &classes, link) { 477 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 478 filename)); 479 error = LINKER_LOAD_FILE(lc, filename, &lf); 480 /* 481 * If we got something other than ENOENT, then it exists but 482 * we cannot load it for some other reason. 483 */ 484 if (error != ENOENT) { 485 foundfile = 1; 486 if (error == EEXIST) 487 break; 488 } 489 if (lf) { 490 error = linker_file_register_modules(lf); 491 if (error == EEXIST) { 492 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 493 return (error); 494 } 495 modules = !TAILQ_EMPTY(&lf->modules); 496 linker_file_register_sysctls(lf, false); 497 #ifdef VIMAGE 498 LINKER_PROPAGATE_VNETS(lf); 499 #endif 500 linker_file_sysinit(lf); 501 lf->flags |= LINKER_FILE_LINKED; 502 503 /* 504 * If all of the modules in this file failed 505 * to load, unload the file and return an 506 * error of ENOEXEC. 507 */ 508 if (modules && TAILQ_EMPTY(&lf->modules)) { 509 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 510 return (ENOEXEC); 511 } 512 linker_file_enable_sysctls(lf); 513 514 /* 515 * Ask the linker to load CTF data for this file. 516 */ 517 linker_ctf_load_file(lf); 518 EVENTHANDLER_INVOKE(kld_load, lf); 519 *result = lf; 520 return (0); 521 } 522 } 523 /* 524 * Less than ideal, but tells the user whether it failed to load or 525 * the module was not found. 526 */ 527 if (foundfile) { 528 /* 529 * If the file type has not been recognized by the last try 530 * printout a message before to fail. 531 */ 532 if (error == ENOSYS) 533 printf("%s: %s - unsupported file type\n", 534 __func__, filename); 535 536 /* 537 * Format not recognized or otherwise unloadable. 538 * When loading a module that is statically built into 539 * the kernel EEXIST percolates back up as the return 540 * value. Preserve this so that apps like sysinstall 541 * can recognize this special case and not post bogus 542 * dialog boxes. 543 */ 544 if (error != EEXIST) 545 error = ENOEXEC; 546 } else 547 error = ENOENT; /* Nothing found */ 548 return (error); 549 } 550 551 int 552 linker_reference_module(const char *modname, struct mod_depend *verinfo, 553 linker_file_t *result) 554 { 555 modlist_t mod; 556 int error; 557 558 sx_xlock(&kld_sx); 559 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 560 *result = mod->container; 561 (*result)->refs++; 562 sx_xunlock(&kld_sx); 563 return (0); 564 } 565 566 error = linker_load_module(NULL, modname, NULL, verinfo, result); 567 sx_xunlock(&kld_sx); 568 return (error); 569 } 570 571 int 572 linker_release_module(const char *modname, struct mod_depend *verinfo, 573 linker_file_t lf) 574 { 575 modlist_t mod; 576 int error; 577 578 sx_xlock(&kld_sx); 579 if (lf == NULL) { 580 KASSERT(modname != NULL, 581 ("linker_release_module: no file or name")); 582 mod = modlist_lookup2(modname, verinfo); 583 if (mod == NULL) { 584 sx_xunlock(&kld_sx); 585 return (ESRCH); 586 } 587 lf = mod->container; 588 } else 589 KASSERT(modname == NULL && verinfo == NULL, 590 ("linker_release_module: both file and name")); 591 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL); 592 sx_xunlock(&kld_sx); 593 return (error); 594 } 595 596 static linker_file_t 597 linker_find_file_by_name(const char *filename) 598 { 599 linker_file_t lf; 600 char *koname; 601 602 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 603 sprintf(koname, "%s.ko", filename); 604 605 sx_assert(&kld_sx, SA_XLOCKED); 606 TAILQ_FOREACH(lf, &linker_files, link) { 607 if (strcmp(lf->filename, koname) == 0) 608 break; 609 if (strcmp(lf->filename, filename) == 0) 610 break; 611 } 612 free(koname, M_LINKER); 613 return (lf); 614 } 615 616 static linker_file_t 617 linker_find_file_by_id(int fileid) 618 { 619 linker_file_t lf; 620 621 sx_assert(&kld_sx, SA_XLOCKED); 622 TAILQ_FOREACH(lf, &linker_files, link) 623 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED) 624 break; 625 return (lf); 626 } 627 628 int 629 linker_file_foreach(linker_predicate_t *predicate, void *context) 630 { 631 linker_file_t lf; 632 int retval = 0; 633 634 sx_xlock(&kld_sx); 635 TAILQ_FOREACH(lf, &linker_files, link) { 636 retval = predicate(lf, context); 637 if (retval != 0) 638 break; 639 } 640 sx_xunlock(&kld_sx); 641 return (retval); 642 } 643 644 linker_file_t 645 linker_make_file(const char *pathname, linker_class_t lc) 646 { 647 linker_file_t lf; 648 const char *filename; 649 650 if (!cold) 651 sx_assert(&kld_sx, SA_XLOCKED); 652 filename = linker_basename(pathname); 653 654 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname)); 655 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 656 if (lf == NULL) 657 return (NULL); 658 lf->ctors_addr = 0; 659 lf->ctors_size = 0; 660 lf->ctors_invoked = LF_NONE; 661 lf->dtors_addr = 0; 662 lf->dtors_size = 0; 663 lf->refs = 1; 664 lf->userrefs = 0; 665 lf->flags = 0; 666 lf->filename = strdup(filename, M_LINKER); 667 lf->pathname = strdup(pathname, M_LINKER); 668 LINKER_GET_NEXT_FILE_ID(lf->id); 669 lf->ndeps = 0; 670 lf->deps = NULL; 671 lf->loadcnt = ++loadcnt; 672 #ifdef __arm__ 673 lf->exidx_addr = 0; 674 lf->exidx_size = 0; 675 #endif 676 STAILQ_INIT(&lf->common); 677 TAILQ_INIT(&lf->modules); 678 TAILQ_INSERT_TAIL(&linker_files, lf, link); 679 return (lf); 680 } 681 682 int 683 linker_file_unload(linker_file_t file, int flags) 684 { 685 module_t mod, next; 686 modlist_t ml, nextml; 687 struct common_symbol *cp; 688 int error, i; 689 690 /* Refuse to unload modules if securelevel raised. */ 691 if (prison0.pr_securelevel > 0) 692 return (EPERM); 693 694 sx_assert(&kld_sx, SA_XLOCKED); 695 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 696 697 /* Easy case of just dropping a reference. */ 698 if (file->refs > 1) { 699 file->refs--; 700 return (0); 701 } 702 703 /* Give eventhandlers a chance to prevent the unload. */ 704 error = 0; 705 EVENTHANDLER_INVOKE(kld_unload_try, file, &error); 706 if (error != 0) 707 return (EBUSY); 708 709 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 710 " informing modules\n")); 711 712 /* 713 * Quiesce all the modules to give them a chance to veto the unload. 714 */ 715 MOD_SLOCK; 716 for (mod = TAILQ_FIRST(&file->modules); mod; 717 mod = module_getfnext(mod)) { 718 error = module_quiesce(mod); 719 if (error != 0 && flags != LINKER_UNLOAD_FORCE) { 720 KLD_DPF(FILE, ("linker_file_unload: module %s" 721 " vetoed unload\n", module_getname(mod))); 722 /* 723 * XXX: Do we need to tell all the quiesced modules 724 * that they can resume work now via a new module 725 * event? 726 */ 727 MOD_SUNLOCK; 728 return (error); 729 } 730 } 731 MOD_SUNLOCK; 732 733 /* 734 * Inform any modules associated with this file that they are 735 * being unloaded. 736 */ 737 MOD_XLOCK; 738 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 739 next = module_getfnext(mod); 740 MOD_XUNLOCK; 741 742 /* 743 * Give the module a chance to veto the unload. 744 */ 745 if ((error = module_unload(mod)) != 0) { 746 #ifdef KLD_DEBUG 747 MOD_SLOCK; 748 KLD_DPF(FILE, ("linker_file_unload: module %s" 749 " failed unload\n", module_getname(mod))); 750 MOD_SUNLOCK; 751 #endif 752 return (error); 753 } 754 MOD_XLOCK; 755 module_release(mod); 756 } 757 MOD_XUNLOCK; 758 759 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 760 if (ml->container == file) { 761 TAILQ_REMOVE(&found_modules, ml, link); 762 free(ml, M_LINKER); 763 } 764 } 765 766 /* 767 * Don't try to run SYSUNINITs if we are unloaded due to a 768 * link error. 769 */ 770 if (file->flags & LINKER_FILE_LINKED) { 771 file->flags &= ~LINKER_FILE_LINKED; 772 linker_file_unregister_sysctls(file); 773 linker_file_sysuninit(file); 774 } 775 TAILQ_REMOVE(&linker_files, file, link); 776 777 if (file->deps) { 778 for (i = 0; i < file->ndeps; i++) 779 linker_file_unload(file->deps[i], flags); 780 free(file->deps, M_LINKER); 781 file->deps = NULL; 782 } 783 while ((cp = STAILQ_FIRST(&file->common)) != NULL) { 784 STAILQ_REMOVE_HEAD(&file->common, link); 785 free(cp, M_LINKER); 786 } 787 788 LINKER_UNLOAD(file); 789 790 EVENTHANDLER_INVOKE(kld_unload, file->filename, file->address, 791 file->size); 792 793 if (file->filename) { 794 free(file->filename, M_LINKER); 795 file->filename = NULL; 796 } 797 if (file->pathname) { 798 free(file->pathname, M_LINKER); 799 file->pathname = NULL; 800 } 801 kobj_delete((kobj_t) file, M_LINKER); 802 return (0); 803 } 804 805 int 806 linker_ctf_get(linker_file_t file, linker_ctf_t *lc) 807 { 808 return (LINKER_CTF_GET(file, lc)); 809 } 810 811 int 812 linker_ctf_lookup_typename_ddb(linker_ctf_t *lc, const char *typename) 813 { 814 #ifdef DDB 815 linker_file_t lf; 816 817 TAILQ_FOREACH (lf, &linker_files, link){ 818 if (LINKER_CTF_LOOKUP_TYPENAME(lf, lc, typename) == 0) 819 return (0); 820 } 821 #endif 822 return (ENOENT); 823 } 824 825 int 826 linker_ctf_lookup_sym_ddb(const char *symname, c_linker_sym_t *sym, 827 linker_ctf_t *lc) 828 { 829 #ifdef DDB 830 linker_file_t lf; 831 832 TAILQ_FOREACH (lf, &linker_files, link){ 833 if (LINKER_LOOKUP_DEBUG_SYMBOL_CTF(lf, symname, sym, lc) == 0) 834 return (0); 835 } 836 #endif 837 return (ENOENT); 838 } 839 840 static void 841 linker_file_add_dependency(linker_file_t file, linker_file_t dep) 842 { 843 linker_file_t *newdeps; 844 845 sx_assert(&kld_sx, SA_XLOCKED); 846 file->deps = realloc(file->deps, (file->ndeps + 1) * sizeof(*newdeps), 847 M_LINKER, M_WAITOK | M_ZERO); 848 file->deps[file->ndeps] = dep; 849 file->ndeps++; 850 KLD_DPF(FILE, ("linker_file_add_dependency:" 851 " adding %s as dependency for %s\n", 852 dep->filename, file->filename)); 853 } 854 855 /* 856 * Locate a linker set and its contents. This is a helper function to avoid 857 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **. 858 * This function is used in this file so we can avoid having lots of (void **) 859 * casts. 860 */ 861 int 862 linker_file_lookup_set(linker_file_t file, const char *name, 863 void *firstp, void *lastp, int *countp) 864 { 865 866 sx_assert(&kld_sx, SA_LOCKED); 867 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 868 } 869 870 /* 871 * List all functions in a file. 872 */ 873 int 874 linker_file_function_listall(linker_file_t lf, 875 linker_function_nameval_callback_t callback_func, void *arg) 876 { 877 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg)); 878 } 879 880 caddr_t 881 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 882 { 883 caddr_t sym; 884 int locked; 885 886 locked = sx_xlocked(&kld_sx); 887 if (!locked) 888 sx_xlock(&kld_sx); 889 sym = linker_file_lookup_symbol_internal(file, name, deps); 890 if (!locked) 891 sx_xunlock(&kld_sx); 892 return (sym); 893 } 894 895 static caddr_t 896 linker_file_lookup_symbol_internal(linker_file_t file, const char *name, 897 int deps) 898 { 899 c_linker_sym_t sym; 900 linker_symval_t symval; 901 caddr_t address; 902 size_t common_size = 0; 903 int i; 904 905 sx_assert(&kld_sx, SA_XLOCKED); 906 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 907 file, name, deps)); 908 909 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 910 LINKER_SYMBOL_VALUES(file, sym, &symval); 911 if (symval.value == 0) 912 /* 913 * For commons, first look them up in the 914 * dependencies and only allocate space if not found 915 * there. 916 */ 917 common_size = symval.size; 918 else { 919 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 920 ".value=%p\n", symval.value)); 921 return (symval.value); 922 } 923 } 924 if (deps) { 925 for (i = 0; i < file->ndeps; i++) { 926 address = linker_file_lookup_symbol_internal( 927 file->deps[i], name, 0); 928 if (address) { 929 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 930 " deps value=%p\n", address)); 931 return (address); 932 } 933 } 934 } 935 if (common_size > 0) { 936 /* 937 * This is a common symbol which was not found in the 938 * dependencies. We maintain a simple common symbol table in 939 * the file object. 940 */ 941 struct common_symbol *cp; 942 943 STAILQ_FOREACH(cp, &file->common, link) { 944 if (strcmp(cp->name, name) == 0) { 945 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 946 " old common value=%p\n", cp->address)); 947 return (cp->address); 948 } 949 } 950 /* 951 * Round the symbol size up to align. 952 */ 953 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 954 cp = malloc(sizeof(struct common_symbol) 955 + common_size + strlen(name) + 1, M_LINKER, 956 M_WAITOK | M_ZERO); 957 cp->address = (caddr_t)(cp + 1); 958 cp->name = cp->address + common_size; 959 strcpy(cp->name, name); 960 bzero(cp->address, common_size); 961 STAILQ_INSERT_TAIL(&file->common, cp, link); 962 963 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 964 " value=%p\n", cp->address)); 965 return (cp->address); 966 } 967 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 968 return (0); 969 } 970 971 /* 972 * Both DDB and stack(9) rely on the kernel linker to provide forward and 973 * backward lookup of symbols. However, DDB and sometimes stack(9) need to 974 * do this in a lockfree manner. We provide a set of internal helper 975 * routines to perform these operations without locks, and then wrappers that 976 * optionally lock. 977 * 978 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB. 979 */ 980 #ifdef DDB 981 static int 982 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym) 983 { 984 linker_file_t lf; 985 986 TAILQ_FOREACH(lf, &linker_files, link) { 987 if (LINKER_LOOKUP_DEBUG_SYMBOL(lf, symstr, sym) == 0) 988 return (0); 989 } 990 return (ENOENT); 991 } 992 #endif 993 994 static int 995 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 996 { 997 linker_file_t lf; 998 c_linker_sym_t best, es; 999 u_long diff, bestdiff, off; 1000 1001 best = 0; 1002 off = (uintptr_t)value; 1003 bestdiff = off; 1004 TAILQ_FOREACH(lf, &linker_files, link) { 1005 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 1006 continue; 1007 if (es != 0 && diff < bestdiff) { 1008 best = es; 1009 bestdiff = diff; 1010 } 1011 if (bestdiff == 0) 1012 break; 1013 } 1014 if (best) { 1015 *sym = best; 1016 *diffp = bestdiff; 1017 return (0); 1018 } else { 1019 *sym = 0; 1020 *diffp = off; 1021 return (ENOENT); 1022 } 1023 } 1024 1025 static int 1026 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 1027 { 1028 linker_file_t lf; 1029 1030 TAILQ_FOREACH(lf, &linker_files, link) { 1031 if (LINKER_DEBUG_SYMBOL_VALUES(lf, sym, symval) == 0) 1032 return (0); 1033 } 1034 return (ENOENT); 1035 } 1036 1037 static int 1038 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1039 long *offset) 1040 { 1041 linker_symval_t symval; 1042 c_linker_sym_t sym; 1043 int error; 1044 1045 *offset = 0; 1046 error = linker_debug_search_symbol(value, &sym, offset); 1047 if (error) 1048 return (error); 1049 error = linker_debug_symbol_values(sym, &symval); 1050 if (error) 1051 return (error); 1052 strlcpy(buf, symval.name, buflen); 1053 return (0); 1054 } 1055 1056 /* 1057 * DDB Helpers. DDB has to look across multiple files with their own symbol 1058 * tables and string tables. 1059 * 1060 * Note that we do not obey list locking protocols here. We really don't need 1061 * DDB to hang because somebody's got the lock held. We'll take the chance 1062 * that the files list is inconsistent instead. 1063 */ 1064 #ifdef DDB 1065 int 1066 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 1067 { 1068 1069 return (linker_debug_lookup(symstr, sym)); 1070 } 1071 #endif 1072 1073 int 1074 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 1075 { 1076 1077 return (linker_debug_search_symbol(value, sym, diffp)); 1078 } 1079 1080 int 1081 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 1082 { 1083 1084 return (linker_debug_symbol_values(sym, symval)); 1085 } 1086 1087 int 1088 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1089 long *offset) 1090 { 1091 1092 return (linker_debug_search_symbol_name(value, buf, buflen, offset)); 1093 } 1094 1095 /* 1096 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do 1097 * obey locking protocols, and offer a significantly less complex interface. 1098 */ 1099 int 1100 linker_search_symbol_name_flags(caddr_t value, char *buf, u_int buflen, 1101 long *offset, int flags) 1102 { 1103 int error; 1104 1105 KASSERT((flags & (M_NOWAIT | M_WAITOK)) != 0 && 1106 (flags & (M_NOWAIT | M_WAITOK)) != (M_NOWAIT | M_WAITOK), 1107 ("%s: bad flags: 0x%x", __func__, flags)); 1108 1109 if (flags & M_NOWAIT) { 1110 if (!sx_try_slock(&kld_sx)) 1111 return (EWOULDBLOCK); 1112 } else 1113 sx_slock(&kld_sx); 1114 1115 error = linker_debug_search_symbol_name(value, buf, buflen, offset); 1116 sx_sunlock(&kld_sx); 1117 return (error); 1118 } 1119 1120 int 1121 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1122 long *offset) 1123 { 1124 1125 return (linker_search_symbol_name_flags(value, buf, buflen, offset, 1126 M_WAITOK)); 1127 } 1128 1129 int 1130 linker_kldload_busy(int flags) 1131 { 1132 int error; 1133 1134 MPASS((flags & ~(LINKER_UB_UNLOCK | LINKER_UB_LOCKED | 1135 LINKER_UB_PCATCH)) == 0); 1136 if ((flags & LINKER_UB_LOCKED) != 0) 1137 sx_assert(&kld_sx, SA_XLOCKED); 1138 1139 if ((flags & LINKER_UB_LOCKED) == 0) 1140 sx_xlock(&kld_sx); 1141 while (kld_busy > 0) { 1142 if (kld_busy_owner == curthread) 1143 break; 1144 error = sx_sleep(&kld_busy, &kld_sx, 1145 (flags & LINKER_UB_PCATCH) != 0 ? PCATCH : 0, 1146 "kldbusy", 0); 1147 if (error != 0) { 1148 if ((flags & LINKER_UB_UNLOCK) != 0) 1149 sx_xunlock(&kld_sx); 1150 return (error); 1151 } 1152 } 1153 kld_busy++; 1154 kld_busy_owner = curthread; 1155 if ((flags & LINKER_UB_UNLOCK) != 0) 1156 sx_xunlock(&kld_sx); 1157 return (0); 1158 } 1159 1160 void 1161 linker_kldload_unbusy(int flags) 1162 { 1163 MPASS((flags & ~LINKER_UB_LOCKED) == 0); 1164 if ((flags & LINKER_UB_LOCKED) != 0) 1165 sx_assert(&kld_sx, SA_XLOCKED); 1166 1167 if ((flags & LINKER_UB_LOCKED) == 0) 1168 sx_xlock(&kld_sx); 1169 MPASS(kld_busy > 0); 1170 if (kld_busy_owner != curthread) 1171 panic("linker_kldload_unbusy done by not owning thread %p", 1172 kld_busy_owner); 1173 kld_busy--; 1174 if (kld_busy == 0) { 1175 kld_busy_owner = NULL; 1176 wakeup(&kld_busy); 1177 } 1178 sx_xunlock(&kld_sx); 1179 } 1180 1181 /* 1182 * Syscalls. 1183 */ 1184 int 1185 kern_kldload(struct thread *td, const char *file, int *fileid) 1186 { 1187 const char *kldname, *modname; 1188 linker_file_t lf; 1189 int error; 1190 1191 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1192 return (error); 1193 1194 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 1195 return (error); 1196 1197 /* 1198 * If file does not contain a qualified name or any dot in it 1199 * (kldname.ko, or kldname.ver.ko) treat it as an interface 1200 * name. 1201 */ 1202 if (strchr(file, '/') || strchr(file, '.')) { 1203 kldname = file; 1204 modname = NULL; 1205 } else { 1206 kldname = NULL; 1207 modname = file; 1208 } 1209 1210 error = linker_kldload_busy(LINKER_UB_PCATCH); 1211 if (error != 0) { 1212 sx_xunlock(&kld_sx); 1213 return (error); 1214 } 1215 1216 /* 1217 * It is possible that kldloaded module will attach a new ifnet, 1218 * so vnet context must be set when this ocurs. 1219 */ 1220 CURVNET_SET(TD_TO_VNET(td)); 1221 1222 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 1223 CURVNET_RESTORE(); 1224 1225 if (error == 0) { 1226 lf->userrefs++; 1227 if (fileid != NULL) 1228 *fileid = lf->id; 1229 } 1230 linker_kldload_unbusy(LINKER_UB_LOCKED); 1231 return (error); 1232 } 1233 1234 int 1235 sys_kldload(struct thread *td, struct kldload_args *uap) 1236 { 1237 char *pathname = NULL; 1238 int error, fileid; 1239 1240 td->td_retval[0] = -1; 1241 1242 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1243 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 1244 if (error == 0) { 1245 error = kern_kldload(td, pathname, &fileid); 1246 if (error == 0) 1247 td->td_retval[0] = fileid; 1248 } 1249 free(pathname, M_TEMP); 1250 return (error); 1251 } 1252 1253 int 1254 kern_kldunload(struct thread *td, int fileid, int flags) 1255 { 1256 linker_file_t lf; 1257 int error = 0; 1258 1259 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1260 return (error); 1261 1262 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 1263 return (error); 1264 1265 error = linker_kldload_busy(LINKER_UB_PCATCH); 1266 if (error != 0) { 1267 sx_xunlock(&kld_sx); 1268 return (error); 1269 } 1270 1271 CURVNET_SET(TD_TO_VNET(td)); 1272 lf = linker_find_file_by_id(fileid); 1273 if (lf) { 1274 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 1275 1276 if (lf->userrefs == 0) { 1277 /* 1278 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 1279 */ 1280 printf("kldunload: attempt to unload file that was" 1281 " loaded by the kernel\n"); 1282 error = EBUSY; 1283 } else if (lf->refs > 1) { 1284 error = EBUSY; 1285 } else { 1286 lf->userrefs--; 1287 error = linker_file_unload(lf, flags); 1288 if (error) 1289 lf->userrefs++; 1290 } 1291 } else 1292 error = ENOENT; 1293 CURVNET_RESTORE(); 1294 linker_kldload_unbusy(LINKER_UB_LOCKED); 1295 return (error); 1296 } 1297 1298 int 1299 sys_kldunload(struct thread *td, struct kldunload_args *uap) 1300 { 1301 1302 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 1303 } 1304 1305 int 1306 sys_kldunloadf(struct thread *td, struct kldunloadf_args *uap) 1307 { 1308 1309 if (uap->flags != LINKER_UNLOAD_NORMAL && 1310 uap->flags != LINKER_UNLOAD_FORCE) 1311 return (EINVAL); 1312 return (kern_kldunload(td, uap->fileid, uap->flags)); 1313 } 1314 1315 int 1316 sys_kldfind(struct thread *td, struct kldfind_args *uap) 1317 { 1318 char *pathname; 1319 const char *filename; 1320 linker_file_t lf; 1321 int error; 1322 1323 #ifdef MAC 1324 error = mac_kld_check_stat(td->td_ucred); 1325 if (error) 1326 return (error); 1327 #endif 1328 1329 td->td_retval[0] = -1; 1330 1331 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1332 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1333 goto out; 1334 1335 filename = linker_basename(pathname); 1336 sx_xlock(&kld_sx); 1337 lf = linker_find_file_by_name(filename); 1338 if (lf) 1339 td->td_retval[0] = lf->id; 1340 else 1341 error = ENOENT; 1342 sx_xunlock(&kld_sx); 1343 out: 1344 free(pathname, M_TEMP); 1345 return (error); 1346 } 1347 1348 int 1349 sys_kldnext(struct thread *td, struct kldnext_args *uap) 1350 { 1351 linker_file_t lf; 1352 int error = 0; 1353 1354 #ifdef MAC 1355 error = mac_kld_check_stat(td->td_ucred); 1356 if (error) 1357 return (error); 1358 #endif 1359 1360 sx_xlock(&kld_sx); 1361 if (uap->fileid == 0) 1362 lf = TAILQ_FIRST(&linker_files); 1363 else { 1364 lf = linker_find_file_by_id(uap->fileid); 1365 if (lf == NULL) { 1366 error = ENOENT; 1367 goto out; 1368 } 1369 lf = TAILQ_NEXT(lf, link); 1370 } 1371 1372 /* Skip partially loaded files. */ 1373 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1374 lf = TAILQ_NEXT(lf, link); 1375 1376 if (lf) 1377 td->td_retval[0] = lf->id; 1378 else 1379 td->td_retval[0] = 0; 1380 out: 1381 sx_xunlock(&kld_sx); 1382 return (error); 1383 } 1384 1385 int 1386 sys_kldstat(struct thread *td, struct kldstat_args *uap) 1387 { 1388 struct kld_file_stat *stat; 1389 int error, version; 1390 1391 /* 1392 * Check the version of the user's structure. 1393 */ 1394 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) 1395 != 0) 1396 return (error); 1397 if (version != sizeof(struct kld_file_stat_1) && 1398 version != sizeof(struct kld_file_stat)) 1399 return (EINVAL); 1400 1401 stat = malloc(sizeof(*stat), M_TEMP, M_WAITOK | M_ZERO); 1402 error = kern_kldstat(td, uap->fileid, stat); 1403 if (error == 0) 1404 error = copyout(stat, uap->stat, version); 1405 free(stat, M_TEMP); 1406 return (error); 1407 } 1408 1409 int 1410 kern_kldstat(struct thread *td, int fileid, struct kld_file_stat *stat) 1411 { 1412 linker_file_t lf; 1413 int namelen; 1414 #ifdef MAC 1415 int error; 1416 1417 error = mac_kld_check_stat(td->td_ucred); 1418 if (error) 1419 return (error); 1420 #endif 1421 1422 sx_xlock(&kld_sx); 1423 lf = linker_find_file_by_id(fileid); 1424 if (lf == NULL) { 1425 sx_xunlock(&kld_sx); 1426 return (ENOENT); 1427 } 1428 1429 /* Version 1 fields: */ 1430 namelen = strlen(lf->filename) + 1; 1431 if (namelen > sizeof(stat->name)) 1432 namelen = sizeof(stat->name); 1433 bcopy(lf->filename, &stat->name[0], namelen); 1434 stat->refs = lf->refs; 1435 stat->id = lf->id; 1436 stat->address = lf->address; 1437 stat->size = lf->size; 1438 /* Version 2 fields: */ 1439 namelen = strlen(lf->pathname) + 1; 1440 if (namelen > sizeof(stat->pathname)) 1441 namelen = sizeof(stat->pathname); 1442 bcopy(lf->pathname, &stat->pathname[0], namelen); 1443 sx_xunlock(&kld_sx); 1444 1445 td->td_retval[0] = 0; 1446 return (0); 1447 } 1448 1449 #ifdef DDB 1450 DB_COMMAND_FLAGS(kldstat, db_kldstat, DB_CMD_MEMSAFE) 1451 { 1452 linker_file_t lf; 1453 1454 #define POINTER_WIDTH ((int)(sizeof(void *) * 2 + 2)) 1455 db_printf("Id Refs Address%*c Size Name\n", POINTER_WIDTH - 7, ' '); 1456 #undef POINTER_WIDTH 1457 TAILQ_FOREACH(lf, &linker_files, link) { 1458 if (db_pager_quit) 1459 return; 1460 db_printf("%2d %4d %p %-8zx %s\n", lf->id, lf->refs, 1461 lf->address, lf->size, lf->filename); 1462 } 1463 } 1464 #endif /* DDB */ 1465 1466 int 1467 sys_kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1468 { 1469 linker_file_t lf; 1470 module_t mp; 1471 int error = 0; 1472 1473 #ifdef MAC 1474 error = mac_kld_check_stat(td->td_ucred); 1475 if (error) 1476 return (error); 1477 #endif 1478 1479 sx_xlock(&kld_sx); 1480 lf = linker_find_file_by_id(uap->fileid); 1481 if (lf) { 1482 MOD_SLOCK; 1483 mp = TAILQ_FIRST(&lf->modules); 1484 if (mp != NULL) 1485 td->td_retval[0] = module_getid(mp); 1486 else 1487 td->td_retval[0] = 0; 1488 MOD_SUNLOCK; 1489 } else 1490 error = ENOENT; 1491 sx_xunlock(&kld_sx); 1492 return (error); 1493 } 1494 1495 int 1496 sys_kldsym(struct thread *td, struct kldsym_args *uap) 1497 { 1498 char *symstr = NULL; 1499 c_linker_sym_t sym; 1500 linker_symval_t symval; 1501 linker_file_t lf; 1502 struct kld_sym_lookup lookup; 1503 int error = 0; 1504 1505 #ifdef MAC 1506 error = mac_kld_check_stat(td->td_ucred); 1507 if (error) 1508 return (error); 1509 #endif 1510 1511 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1512 return (error); 1513 if (lookup.version != sizeof(lookup) || 1514 uap->cmd != KLDSYM_LOOKUP) 1515 return (EINVAL); 1516 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1517 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1518 goto out; 1519 sx_xlock(&kld_sx); 1520 if (uap->fileid != 0) { 1521 lf = linker_find_file_by_id(uap->fileid); 1522 if (lf == NULL) 1523 error = ENOENT; 1524 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1525 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1526 lookup.symvalue = (uintptr_t) symval.value; 1527 lookup.symsize = symval.size; 1528 error = copyout(&lookup, uap->data, sizeof(lookup)); 1529 } else 1530 error = ENOENT; 1531 } else { 1532 TAILQ_FOREACH(lf, &linker_files, link) { 1533 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1534 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1535 lookup.symvalue = (uintptr_t)symval.value; 1536 lookup.symsize = symval.size; 1537 error = copyout(&lookup, uap->data, 1538 sizeof(lookup)); 1539 break; 1540 } 1541 } 1542 if (lf == NULL) 1543 error = ENOENT; 1544 } 1545 sx_xunlock(&kld_sx); 1546 out: 1547 free(symstr, M_TEMP); 1548 return (error); 1549 } 1550 1551 /* 1552 * Preloaded module support 1553 */ 1554 1555 static modlist_t 1556 modlist_lookup(const char *name, int ver) 1557 { 1558 modlist_t mod; 1559 1560 TAILQ_FOREACH(mod, &found_modules, link) { 1561 if (strcmp(mod->name, name) == 0 && 1562 (ver == 0 || mod->version == ver)) 1563 return (mod); 1564 } 1565 return (NULL); 1566 } 1567 1568 static modlist_t 1569 modlist_lookup2(const char *name, const struct mod_depend *verinfo) 1570 { 1571 modlist_t mod, bestmod; 1572 int ver; 1573 1574 if (verinfo == NULL) 1575 return (modlist_lookup(name, 0)); 1576 bestmod = NULL; 1577 TAILQ_FOREACH(mod, &found_modules, link) { 1578 if (strcmp(mod->name, name) != 0) 1579 continue; 1580 ver = mod->version; 1581 if (ver == verinfo->md_ver_preferred) 1582 return (mod); 1583 if (ver >= verinfo->md_ver_minimum && 1584 ver <= verinfo->md_ver_maximum && 1585 (bestmod == NULL || ver > bestmod->version)) 1586 bestmod = mod; 1587 } 1588 return (bestmod); 1589 } 1590 1591 static modlist_t 1592 modlist_newmodule(const char *modname, int version, linker_file_t container) 1593 { 1594 modlist_t mod; 1595 1596 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1597 if (mod == NULL) 1598 panic("no memory for module list"); 1599 mod->container = container; 1600 mod->name = modname; 1601 mod->version = version; 1602 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1603 return (mod); 1604 } 1605 1606 static void 1607 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1608 struct mod_metadata **stop, int preload) 1609 { 1610 struct mod_metadata *mp, **mdp; 1611 const char *modname; 1612 int ver; 1613 1614 for (mdp = start; mdp < stop; mdp++) { 1615 mp = *mdp; 1616 if (mp->md_type != MDT_VERSION) 1617 continue; 1618 modname = mp->md_cval; 1619 ver = ((const struct mod_version *)mp->md_data)->mv_version; 1620 if (modlist_lookup(modname, ver) != NULL) { 1621 printf("module %s already present!\n", modname); 1622 /* XXX what can we do? this is a build error. :-( */ 1623 continue; 1624 } 1625 modlist_newmodule(modname, ver, lf); 1626 } 1627 } 1628 1629 static void 1630 linker_preload(void *arg) 1631 { 1632 caddr_t modptr; 1633 const char *modname, *nmodname; 1634 char *modtype; 1635 linker_file_t lf, nlf; 1636 linker_class_t lc; 1637 int error; 1638 linker_file_list_t loaded_files; 1639 linker_file_list_t depended_files; 1640 struct mod_metadata *mp, *nmp; 1641 struct mod_metadata **start, **stop, **mdp, **nmdp; 1642 const struct mod_depend *verinfo; 1643 int nver; 1644 int resolves; 1645 modlist_t mod; 1646 struct sysinit **si_start, **si_stop; 1647 1648 TAILQ_INIT(&loaded_files); 1649 TAILQ_INIT(&depended_files); 1650 TAILQ_INIT(&found_modules); 1651 error = 0; 1652 1653 modptr = NULL; 1654 sx_xlock(&kld_sx); 1655 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1656 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1657 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1658 if (modname == NULL) { 1659 printf("Preloaded module at %p does not have a" 1660 " name!\n", modptr); 1661 continue; 1662 } 1663 if (modtype == NULL) { 1664 printf("Preloaded module at %p does not have a type!\n", 1665 modptr); 1666 continue; 1667 } 1668 if (bootverbose) 1669 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1670 modptr); 1671 lf = NULL; 1672 TAILQ_FOREACH(lc, &classes, link) { 1673 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1674 if (!error) 1675 break; 1676 lf = NULL; 1677 } 1678 if (lf) 1679 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1680 } 1681 1682 /* 1683 * First get a list of stuff in the kernel. 1684 */ 1685 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1686 &stop, NULL) == 0) 1687 linker_addmodules(linker_kernel_file, start, stop, 1); 1688 1689 /* 1690 * This is a once-off kinky bubble sort to resolve relocation 1691 * dependency requirements. 1692 */ 1693 restart: 1694 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1695 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1696 &stop, NULL); 1697 /* 1698 * First, look to see if we would successfully link with this 1699 * stuff. 1700 */ 1701 resolves = 1; /* unless we know otherwise */ 1702 if (!error) { 1703 for (mdp = start; mdp < stop; mdp++) { 1704 mp = *mdp; 1705 if (mp->md_type != MDT_DEPEND) 1706 continue; 1707 modname = mp->md_cval; 1708 verinfo = mp->md_data; 1709 for (nmdp = start; nmdp < stop; nmdp++) { 1710 nmp = *nmdp; 1711 if (nmp->md_type != MDT_VERSION) 1712 continue; 1713 nmodname = nmp->md_cval; 1714 if (strcmp(modname, nmodname) == 0) 1715 break; 1716 } 1717 if (nmdp < stop) /* it's a self reference */ 1718 continue; 1719 1720 /* 1721 * ok, the module isn't here yet, we 1722 * are not finished 1723 */ 1724 if (modlist_lookup2(modname, verinfo) == NULL) 1725 resolves = 0; 1726 } 1727 } 1728 /* 1729 * OK, if we found our modules, we can link. So, "provide" 1730 * the modules inside and add it to the end of the link order 1731 * list. 1732 */ 1733 if (resolves) { 1734 if (!error) { 1735 for (mdp = start; mdp < stop; mdp++) { 1736 mp = *mdp; 1737 if (mp->md_type != MDT_VERSION) 1738 continue; 1739 modname = mp->md_cval; 1740 nver = ((const struct mod_version *) 1741 mp->md_data)->mv_version; 1742 if (modlist_lookup(modname, 1743 nver) != NULL) { 1744 printf("module %s already" 1745 " present!\n", modname); 1746 TAILQ_REMOVE(&loaded_files, 1747 lf, loaded); 1748 linker_file_unload(lf, 1749 LINKER_UNLOAD_FORCE); 1750 /* we changed tailq next ptr */ 1751 goto restart; 1752 } 1753 modlist_newmodule(modname, nver, lf); 1754 } 1755 } 1756 TAILQ_REMOVE(&loaded_files, lf, loaded); 1757 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1758 /* 1759 * Since we provided modules, we need to restart the 1760 * sort so that the previous files that depend on us 1761 * have a chance. Also, we've busted the tailq next 1762 * pointer with the REMOVE. 1763 */ 1764 goto restart; 1765 } 1766 } 1767 1768 /* 1769 * At this point, we check to see what could not be resolved.. 1770 */ 1771 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1772 TAILQ_REMOVE(&loaded_files, lf, loaded); 1773 printf("KLD file %s is missing dependencies\n", lf->filename); 1774 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1775 } 1776 1777 /* 1778 * We made it. Finish off the linking in the order we determined. 1779 */ 1780 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1781 if (linker_kernel_file) { 1782 linker_kernel_file->refs++; 1783 linker_file_add_dependency(lf, linker_kernel_file); 1784 } 1785 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1786 &stop, NULL); 1787 if (!error) { 1788 for (mdp = start; mdp < stop; mdp++) { 1789 mp = *mdp; 1790 if (mp->md_type != MDT_DEPEND) 1791 continue; 1792 modname = mp->md_cval; 1793 verinfo = mp->md_data; 1794 mod = modlist_lookup2(modname, verinfo); 1795 if (mod == NULL) { 1796 printf("KLD file %s - cannot find " 1797 "dependency \"%s\"\n", 1798 lf->filename, modname); 1799 goto fail; 1800 } 1801 /* Don't count self-dependencies */ 1802 if (lf == mod->container) 1803 continue; 1804 mod->container->refs++; 1805 linker_file_add_dependency(lf, mod->container); 1806 } 1807 } 1808 /* 1809 * Now do relocation etc using the symbol search paths 1810 * established by the dependencies 1811 */ 1812 error = LINKER_LINK_PRELOAD_FINISH(lf); 1813 if (error) { 1814 printf("KLD file %s - could not finalize loading\n", 1815 lf->filename); 1816 goto fail; 1817 } 1818 linker_file_register_modules(lf); 1819 if (!TAILQ_EMPTY(&lf->modules)) 1820 lf->flags |= LINKER_FILE_MODULES; 1821 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1822 &si_stop, NULL) == 0) 1823 sysinit_add(si_start, si_stop); 1824 linker_file_register_sysctls(lf, true); 1825 lf->flags |= LINKER_FILE_LINKED; 1826 continue; 1827 fail: 1828 TAILQ_REMOVE(&depended_files, lf, loaded); 1829 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1830 } 1831 sx_xunlock(&kld_sx); 1832 /* woohoo! we made it! */ 1833 } 1834 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, NULL); 1835 1836 static void 1837 linker_mountroot(void *arg __unused) 1838 { 1839 linker_file_t lf; 1840 1841 sx_xlock(&kld_sx); 1842 TAILQ_FOREACH (lf, &linker_files, link) { 1843 linker_ctf_load_file(lf); 1844 } 1845 sx_xunlock(&kld_sx); 1846 } 1847 EVENTHANDLER_DEFINE(mountroot, linker_mountroot, NULL, 0); 1848 1849 /* 1850 * Handle preload files that failed to load any modules. 1851 */ 1852 static void 1853 linker_preload_finish(void *arg) 1854 { 1855 linker_file_t lf, nlf; 1856 1857 sx_xlock(&kld_sx); 1858 TAILQ_FOREACH_SAFE(lf, &linker_files, link, nlf) { 1859 if (lf == linker_kernel_file) 1860 continue; 1861 1862 /* 1863 * If all of the modules in this file failed to load, unload 1864 * the file and return an error of ENOEXEC. (Parity with 1865 * linker_load_file.) 1866 */ 1867 if ((lf->flags & LINKER_FILE_MODULES) != 0 && 1868 TAILQ_EMPTY(&lf->modules)) { 1869 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1870 continue; 1871 } 1872 1873 lf->flags &= ~LINKER_FILE_MODULES; 1874 lf->userrefs++; /* so we can (try to) kldunload it */ 1875 } 1876 sx_xunlock(&kld_sx); 1877 } 1878 1879 /* 1880 * Attempt to run after all DECLARE_MODULE SYSINITs. Unfortunately they can be 1881 * scheduled at any subsystem and order, so run this as late as possible. init 1882 * becomes runnable in SI_SUB_KTHREAD_INIT, so go slightly before that. 1883 */ 1884 SYSINIT(preload_finish, SI_SUB_KTHREAD_INIT - 100, SI_ORDER_MIDDLE, 1885 linker_preload_finish, NULL); 1886 1887 /* 1888 * Search for a not-loaded module by name. 1889 * 1890 * Modules may be found in the following locations: 1891 * 1892 * - preloaded (result is just the module name) - on disk (result is full path 1893 * to module) 1894 * 1895 * If the module name is qualified in any way (contains path, etc.) the we 1896 * simply return a copy of it. 1897 * 1898 * The search path can be manipulated via sysctl. Note that we use the ';' 1899 * character as a separator to be consistent with the bootloader. 1900 */ 1901 1902 static char linker_hintfile[] = "linker.hints"; 1903 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1904 1905 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RWTUN, linker_path, 1906 sizeof(linker_path), "module load search path"); 1907 1908 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1909 1910 static const char * const linker_ext_list[] = { 1911 "", 1912 ".ko", 1913 NULL 1914 }; 1915 1916 /* 1917 * Check if file actually exists either with or without extension listed in 1918 * the linker_ext_list. (probably should be generic for the rest of the 1919 * kernel) 1920 */ 1921 static char * 1922 linker_lookup_file(const char *path, int pathlen, const char *name, 1923 int namelen, struct vattr *vap) 1924 { 1925 struct nameidata nd; 1926 struct thread *td = curthread; /* XXX */ 1927 const char * const *cpp, *sep; 1928 char *result; 1929 int error, len, extlen, reclen, flags; 1930 __enum_uint8(vtype) type; 1931 1932 extlen = 0; 1933 for (cpp = linker_ext_list; *cpp; cpp++) { 1934 len = strlen(*cpp); 1935 if (len > extlen) 1936 extlen = len; 1937 } 1938 extlen++; /* trailing '\0' */ 1939 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1940 1941 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1942 result = malloc(reclen, M_LINKER, M_WAITOK); 1943 for (cpp = linker_ext_list; *cpp; cpp++) { 1944 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1945 namelen, name, *cpp); 1946 /* 1947 * Attempt to open the file, and return the path if 1948 * we succeed and it's a regular file. 1949 */ 1950 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result); 1951 flags = FREAD; 1952 error = vn_open(&nd, &flags, 0, NULL); 1953 if (error == 0) { 1954 NDFREE_PNBUF(&nd); 1955 type = nd.ni_vp->v_type; 1956 if (vap) 1957 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred); 1958 VOP_UNLOCK(nd.ni_vp); 1959 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1960 if (type == VREG) 1961 return (result); 1962 } 1963 } 1964 free(result, M_LINKER); 1965 return (NULL); 1966 } 1967 1968 #define INT_ALIGN(base, ptr) ptr = \ 1969 (base) + roundup2((ptr) - (base), sizeof(int)) 1970 1971 /* 1972 * Lookup KLD which contains requested module in the "linker.hints" file. If 1973 * version specification is available, then try to find the best KLD. 1974 * Otherwise just find the latest one. 1975 */ 1976 static char * 1977 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1978 int modnamelen, const struct mod_depend *verinfo) 1979 { 1980 struct thread *td = curthread; /* XXX */ 1981 struct ucred *cred = td ? td->td_ucred : NULL; 1982 struct nameidata nd; 1983 struct vattr vattr, mattr; 1984 const char *best, *sep; 1985 u_char *hints = NULL; 1986 u_char *cp, *recptr, *bufend, *result, *pathbuf; 1987 int error, ival, bestver, *intp, found, flags, clen, blen; 1988 ssize_t reclen; 1989 1990 result = NULL; 1991 bestver = found = 0; 1992 1993 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1994 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1995 strlen(sep) + 1; 1996 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1997 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1998 linker_hintfile); 1999 2000 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf); 2001 flags = FREAD; 2002 error = vn_open(&nd, &flags, 0, NULL); 2003 if (error) 2004 goto bad; 2005 NDFREE_PNBUF(&nd); 2006 if (nd.ni_vp->v_type != VREG) 2007 goto bad; 2008 best = cp = NULL; 2009 error = VOP_GETATTR(nd.ni_vp, &vattr, cred); 2010 if (error) 2011 goto bad; 2012 /* 2013 * XXX: we need to limit this number to some reasonable value 2014 */ 2015 if (vattr.va_size > LINKER_HINTS_MAX) { 2016 printf("linker.hints file too large %ld\n", (long)vattr.va_size); 2017 goto bad; 2018 } 2019 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 2020 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 2021 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 2022 if (error) 2023 goto bad; 2024 VOP_UNLOCK(nd.ni_vp); 2025 vn_close(nd.ni_vp, FREAD, cred, td); 2026 nd.ni_vp = NULL; 2027 if (reclen != 0) { 2028 printf("can't read %zd\n", reclen); 2029 goto bad; 2030 } 2031 intp = (int *)hints; 2032 ival = *intp++; 2033 if (ival != LINKER_HINTS_VERSION) { 2034 printf("linker.hints file version mismatch %d\n", ival); 2035 goto bad; 2036 } 2037 bufend = hints + vattr.va_size; 2038 recptr = (u_char *)intp; 2039 clen = blen = 0; 2040 while (recptr < bufend && !found) { 2041 intp = (int *)recptr; 2042 reclen = *intp++; 2043 ival = *intp++; 2044 cp = (char *)intp; 2045 switch (ival) { 2046 case MDT_VERSION: 2047 clen = *cp++; 2048 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 2049 break; 2050 cp += clen; 2051 INT_ALIGN(hints, cp); 2052 ival = *(int *)cp; 2053 cp += sizeof(int); 2054 clen = *cp++; 2055 if (verinfo == NULL || 2056 ival == verinfo->md_ver_preferred) { 2057 found = 1; 2058 break; 2059 } 2060 if (ival >= verinfo->md_ver_minimum && 2061 ival <= verinfo->md_ver_maximum && 2062 ival > bestver) { 2063 bestver = ival; 2064 best = cp; 2065 blen = clen; 2066 } 2067 break; 2068 default: 2069 break; 2070 } 2071 recptr += reclen + sizeof(int); 2072 } 2073 /* 2074 * Finally check if KLD is in the place 2075 */ 2076 if (found) 2077 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 2078 else if (best) 2079 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 2080 2081 /* 2082 * KLD is newer than hints file. What we should do now? 2083 */ 2084 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 2085 printf("warning: KLD '%s' is newer than the linker.hints" 2086 " file\n", result); 2087 bad: 2088 free(pathbuf, M_LINKER); 2089 if (hints) 2090 free(hints, M_TEMP); 2091 if (nd.ni_vp != NULL) { 2092 VOP_UNLOCK(nd.ni_vp); 2093 vn_close(nd.ni_vp, FREAD, cred, td); 2094 } 2095 /* 2096 * If nothing found or hints is absent - fallback to the old 2097 * way by using "kldname[.ko]" as module name. 2098 */ 2099 if (!found && !bestver && result == NULL) 2100 result = linker_lookup_file(path, pathlen, modname, 2101 modnamelen, NULL); 2102 return (result); 2103 } 2104 2105 /* 2106 * Lookup KLD which contains requested module in the all directories. 2107 */ 2108 static char * 2109 linker_search_module(const char *modname, int modnamelen, 2110 const struct mod_depend *verinfo) 2111 { 2112 char *cp, *ep, *result; 2113 2114 /* 2115 * traverse the linker path 2116 */ 2117 for (cp = linker_path; *cp; cp = ep + 1) { 2118 /* find the end of this component */ 2119 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 2120 result = linker_hints_lookup(cp, ep - cp, modname, 2121 modnamelen, verinfo); 2122 if (result != NULL) 2123 return (result); 2124 if (*ep == 0) 2125 break; 2126 } 2127 return (NULL); 2128 } 2129 2130 /* 2131 * Search for module in all directories listed in the linker_path. 2132 */ 2133 static char * 2134 linker_search_kld(const char *name) 2135 { 2136 char *cp, *ep, *result; 2137 int len; 2138 2139 /* qualified at all? */ 2140 if (strchr(name, '/')) 2141 return (strdup(name, M_LINKER)); 2142 2143 /* traverse the linker path */ 2144 len = strlen(name); 2145 for (ep = linker_path; *ep; ep++) { 2146 cp = ep; 2147 /* find the end of this component */ 2148 for (; *ep != 0 && *ep != ';'; ep++); 2149 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 2150 if (result != NULL) 2151 return (result); 2152 } 2153 return (NULL); 2154 } 2155 2156 static const char * 2157 linker_basename(const char *path) 2158 { 2159 const char *filename; 2160 2161 filename = strrchr(path, '/'); 2162 if (filename == NULL) 2163 return path; 2164 if (filename[1]) 2165 filename++; 2166 return (filename); 2167 } 2168 2169 #ifdef HWPMC_HOOKS 2170 /* 2171 * Inform hwpmc about the set of kernel modules currently loaded. 2172 */ 2173 void * 2174 linker_hwpmc_list_objects(void) 2175 { 2176 linker_file_t lf; 2177 struct pmckern_map_in *kobase; 2178 int i, nmappings; 2179 2180 nmappings = 0; 2181 sx_slock(&kld_sx); 2182 TAILQ_FOREACH(lf, &linker_files, link) 2183 nmappings++; 2184 2185 /* Allocate nmappings + 1 entries. */ 2186 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in), 2187 M_LINKER, M_WAITOK | M_ZERO); 2188 i = 0; 2189 TAILQ_FOREACH(lf, &linker_files, link) { 2190 /* Save the info for this linker file. */ 2191 kobase[i].pm_file = lf->pathname; 2192 kobase[i].pm_address = (uintptr_t)lf->address; 2193 i++; 2194 } 2195 sx_sunlock(&kld_sx); 2196 2197 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?")); 2198 2199 /* The last entry of the malloced area comprises of all zeros. */ 2200 KASSERT(kobase[i].pm_file == NULL, 2201 ("linker_hwpmc_list_objects: last object not NULL")); 2202 2203 return ((void *)kobase); 2204 } 2205 #endif 2206 2207 /* check if root file system is not mounted */ 2208 static bool 2209 linker_root_mounted(void) 2210 { 2211 struct pwd *pwd; 2212 bool ret; 2213 2214 if (rootvnode == NULL) 2215 return (false); 2216 2217 pwd = pwd_hold(curthread); 2218 ret = pwd->pwd_rdir != NULL; 2219 pwd_drop(pwd); 2220 return (ret); 2221 } 2222 2223 /* 2224 * Find a file which contains given module and load it, if "parent" is not 2225 * NULL, register a reference to it. 2226 */ 2227 static int 2228 linker_load_module(const char *kldname, const char *modname, 2229 struct linker_file *parent, const struct mod_depend *verinfo, 2230 struct linker_file **lfpp) 2231 { 2232 linker_file_t lfdep; 2233 const char *filename; 2234 char *pathname; 2235 int error; 2236 2237 sx_assert(&kld_sx, SA_XLOCKED); 2238 if (modname == NULL) { 2239 /* 2240 * We have to load KLD 2241 */ 2242 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 2243 " is not NULL")); 2244 if (!linker_root_mounted()) 2245 return (ENXIO); 2246 pathname = linker_search_kld(kldname); 2247 } else { 2248 if (modlist_lookup2(modname, verinfo) != NULL) 2249 return (EEXIST); 2250 if (!linker_root_mounted()) 2251 return (ENXIO); 2252 if (kldname != NULL) 2253 pathname = strdup(kldname, M_LINKER); 2254 else 2255 /* 2256 * Need to find a KLD with required module 2257 */ 2258 pathname = linker_search_module(modname, 2259 strlen(modname), verinfo); 2260 } 2261 if (pathname == NULL) 2262 return (ENOENT); 2263 2264 /* 2265 * Can't load more than one file with the same basename XXX: 2266 * Actually it should be possible to have multiple KLDs with 2267 * the same basename but different path because they can 2268 * provide different versions of the same modules. 2269 */ 2270 filename = linker_basename(pathname); 2271 if (linker_find_file_by_name(filename)) 2272 error = EEXIST; 2273 else do { 2274 error = linker_load_file(pathname, &lfdep); 2275 if (error) 2276 break; 2277 if (modname && verinfo && 2278 modlist_lookup2(modname, verinfo) == NULL) { 2279 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 2280 error = ENOENT; 2281 break; 2282 } 2283 if (parent) 2284 linker_file_add_dependency(parent, lfdep); 2285 if (lfpp) 2286 *lfpp = lfdep; 2287 } while (0); 2288 free(pathname, M_LINKER); 2289 return (error); 2290 } 2291 2292 /* 2293 * This routine is responsible for finding dependencies of userland initiated 2294 * kldload(2)'s of files. 2295 */ 2296 int 2297 linker_load_dependencies(linker_file_t lf) 2298 { 2299 linker_file_t lfdep; 2300 struct mod_metadata **start, **stop, **mdp, **nmdp; 2301 struct mod_metadata *mp, *nmp; 2302 const struct mod_depend *verinfo; 2303 modlist_t mod; 2304 const char *modname, *nmodname; 2305 int ver, error = 0; 2306 2307 /* 2308 * All files are dependent on /kernel. 2309 */ 2310 sx_assert(&kld_sx, SA_XLOCKED); 2311 if (linker_kernel_file) { 2312 linker_kernel_file->refs++; 2313 linker_file_add_dependency(lf, linker_kernel_file); 2314 } 2315 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 2316 NULL) != 0) 2317 return (0); 2318 for (mdp = start; mdp < stop; mdp++) { 2319 mp = *mdp; 2320 if (mp->md_type != MDT_VERSION) 2321 continue; 2322 modname = mp->md_cval; 2323 ver = ((const struct mod_version *)mp->md_data)->mv_version; 2324 mod = modlist_lookup(modname, ver); 2325 if (mod != NULL) { 2326 printf("interface %s.%d already present in the KLD" 2327 " '%s'!\n", modname, ver, 2328 mod->container->filename); 2329 return (EEXIST); 2330 } 2331 } 2332 2333 for (mdp = start; mdp < stop; mdp++) { 2334 mp = *mdp; 2335 if (mp->md_type != MDT_DEPEND) 2336 continue; 2337 modname = mp->md_cval; 2338 verinfo = mp->md_data; 2339 nmodname = NULL; 2340 for (nmdp = start; nmdp < stop; nmdp++) { 2341 nmp = *nmdp; 2342 if (nmp->md_type != MDT_VERSION) 2343 continue; 2344 nmodname = nmp->md_cval; 2345 if (strcmp(modname, nmodname) == 0) 2346 break; 2347 } 2348 if (nmdp < stop)/* early exit, it's a self reference */ 2349 continue; 2350 mod = modlist_lookup2(modname, verinfo); 2351 if (mod) { /* woohoo, it's loaded already */ 2352 lfdep = mod->container; 2353 lfdep->refs++; 2354 linker_file_add_dependency(lf, lfdep); 2355 continue; 2356 } 2357 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 2358 if (error) { 2359 printf("KLD %s: depends on %s - not available or" 2360 " version mismatch\n", lf->filename, modname); 2361 break; 2362 } 2363 } 2364 2365 if (error) 2366 return (error); 2367 linker_addmodules(lf, start, stop, 0); 2368 return (error); 2369 } 2370 2371 static int 2372 sysctl_kern_function_list_iterate(const char *name, void *opaque) 2373 { 2374 struct sysctl_req *req; 2375 2376 req = opaque; 2377 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 2378 } 2379 2380 /* 2381 * Export a nul-separated, double-nul-terminated list of all function names 2382 * in the kernel. 2383 */ 2384 static int 2385 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 2386 { 2387 linker_file_t lf; 2388 int error; 2389 2390 #ifdef MAC 2391 error = mac_kld_check_stat(req->td->td_ucred); 2392 if (error) 2393 return (error); 2394 #endif 2395 error = sysctl_wire_old_buffer(req, 0); 2396 if (error != 0) 2397 return (error); 2398 sx_xlock(&kld_sx); 2399 TAILQ_FOREACH(lf, &linker_files, link) { 2400 error = LINKER_EACH_FUNCTION_NAME(lf, 2401 sysctl_kern_function_list_iterate, req); 2402 if (error) { 2403 sx_xunlock(&kld_sx); 2404 return (error); 2405 } 2406 } 2407 sx_xunlock(&kld_sx); 2408 return (SYSCTL_OUT(req, "", 1)); 2409 } 2410 2411 SYSCTL_PROC(_kern, OID_AUTO, function_list, 2412 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 2413 sysctl_kern_function_list, "", 2414 "kernel function list"); 2415