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