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 /* 910 * Treat the __this_linker_file as a special symbol. This is a 911 * global that linuxkpi uses to populate the THIS_MODULE 912 * value. In this case we can simply return the linker_file_t. 913 * 914 * Modules compiled statically into the kernel are assigned NULL. 915 */ 916 if (strcmp(name, "__this_linker_file") == 0) { 917 address = (file == linker_kernel_file) ? NULL : (caddr_t)file; 918 KLD_DPF(SYM, ("linker_file_lookup_symbol: resolving special " 919 "symbol __this_linker_file to %p\n", address)); 920 return (address); 921 } 922 923 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 924 LINKER_SYMBOL_VALUES(file, sym, &symval); 925 if (symval.value == 0) 926 /* 927 * For commons, first look them up in the 928 * dependencies and only allocate space if not found 929 * there. 930 */ 931 common_size = symval.size; 932 else { 933 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 934 ".value=%p\n", symval.value)); 935 return (symval.value); 936 } 937 } 938 if (deps) { 939 for (i = 0; i < file->ndeps; i++) { 940 address = linker_file_lookup_symbol_internal( 941 file->deps[i], name, 0); 942 if (address) { 943 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 944 " deps value=%p\n", address)); 945 return (address); 946 } 947 } 948 } 949 if (common_size > 0) { 950 /* 951 * This is a common symbol which was not found in the 952 * dependencies. We maintain a simple common symbol table in 953 * the file object. 954 */ 955 struct common_symbol *cp; 956 957 STAILQ_FOREACH(cp, &file->common, link) { 958 if (strcmp(cp->name, name) == 0) { 959 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 960 " old common value=%p\n", cp->address)); 961 return (cp->address); 962 } 963 } 964 /* 965 * Round the symbol size up to align. 966 */ 967 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 968 cp = malloc(sizeof(struct common_symbol) 969 + common_size + strlen(name) + 1, M_LINKER, 970 M_WAITOK | M_ZERO); 971 cp->address = (caddr_t)(cp + 1); 972 cp->name = cp->address + common_size; 973 strcpy(cp->name, name); 974 bzero(cp->address, common_size); 975 STAILQ_INSERT_TAIL(&file->common, cp, link); 976 977 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 978 " value=%p\n", cp->address)); 979 return (cp->address); 980 } 981 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 982 return (0); 983 } 984 985 /* 986 * Both DDB and stack(9) rely on the kernel linker to provide forward and 987 * backward lookup of symbols. However, DDB and sometimes stack(9) need to 988 * do this in a lockfree manner. We provide a set of internal helper 989 * routines to perform these operations without locks, and then wrappers that 990 * optionally lock. 991 * 992 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB. 993 */ 994 #ifdef DDB 995 static int 996 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym) 997 { 998 linker_file_t lf; 999 1000 TAILQ_FOREACH(lf, &linker_files, link) { 1001 if (LINKER_LOOKUP_DEBUG_SYMBOL(lf, symstr, sym) == 0) 1002 return (0); 1003 } 1004 return (ENOENT); 1005 } 1006 #endif 1007 1008 static int 1009 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 1010 { 1011 linker_file_t lf; 1012 c_linker_sym_t best, es; 1013 u_long diff, bestdiff, off; 1014 1015 best = 0; 1016 off = (uintptr_t)value; 1017 bestdiff = off; 1018 TAILQ_FOREACH(lf, &linker_files, link) { 1019 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 1020 continue; 1021 if (es != 0 && diff < bestdiff) { 1022 best = es; 1023 bestdiff = diff; 1024 } 1025 if (bestdiff == 0) 1026 break; 1027 } 1028 if (best) { 1029 *sym = best; 1030 *diffp = bestdiff; 1031 return (0); 1032 } else { 1033 *sym = 0; 1034 *diffp = off; 1035 return (ENOENT); 1036 } 1037 } 1038 1039 static int 1040 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 1041 { 1042 linker_file_t lf; 1043 1044 TAILQ_FOREACH(lf, &linker_files, link) { 1045 if (LINKER_DEBUG_SYMBOL_VALUES(lf, sym, symval) == 0) 1046 return (0); 1047 } 1048 return (ENOENT); 1049 } 1050 1051 static int 1052 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1053 long *offset) 1054 { 1055 linker_symval_t symval; 1056 c_linker_sym_t sym; 1057 int error; 1058 1059 *offset = 0; 1060 error = linker_debug_search_symbol(value, &sym, offset); 1061 if (error) 1062 return (error); 1063 error = linker_debug_symbol_values(sym, &symval); 1064 if (error) 1065 return (error); 1066 strlcpy(buf, symval.name, buflen); 1067 return (0); 1068 } 1069 1070 /* 1071 * DDB Helpers. DDB has to look across multiple files with their own symbol 1072 * tables and string tables. 1073 * 1074 * Note that we do not obey list locking protocols here. We really don't need 1075 * DDB to hang because somebody's got the lock held. We'll take the chance 1076 * that the files list is inconsistent instead. 1077 */ 1078 #ifdef DDB 1079 int 1080 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 1081 { 1082 1083 return (linker_debug_lookup(symstr, sym)); 1084 } 1085 #endif 1086 1087 int 1088 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 1089 { 1090 1091 return (linker_debug_search_symbol(value, sym, diffp)); 1092 } 1093 1094 int 1095 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 1096 { 1097 1098 return (linker_debug_symbol_values(sym, symval)); 1099 } 1100 1101 int 1102 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1103 long *offset) 1104 { 1105 1106 return (linker_debug_search_symbol_name(value, buf, buflen, offset)); 1107 } 1108 1109 /* 1110 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do 1111 * obey locking protocols, and offer a significantly less complex interface. 1112 */ 1113 int 1114 linker_search_symbol_name_flags(caddr_t value, char *buf, u_int buflen, 1115 long *offset, int flags) 1116 { 1117 int error; 1118 1119 KASSERT((flags & (M_NOWAIT | M_WAITOK)) != 0 && 1120 (flags & (M_NOWAIT | M_WAITOK)) != (M_NOWAIT | M_WAITOK), 1121 ("%s: bad flags: 0x%x", __func__, flags)); 1122 1123 if (flags & M_NOWAIT) { 1124 if (!sx_try_slock(&kld_sx)) 1125 return (EWOULDBLOCK); 1126 } else 1127 sx_slock(&kld_sx); 1128 1129 error = linker_debug_search_symbol_name(value, buf, buflen, offset); 1130 sx_sunlock(&kld_sx); 1131 return (error); 1132 } 1133 1134 int 1135 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 1136 long *offset) 1137 { 1138 1139 return (linker_search_symbol_name_flags(value, buf, buflen, offset, 1140 M_WAITOK)); 1141 } 1142 1143 int 1144 linker_kldload_busy(int flags) 1145 { 1146 int error; 1147 1148 MPASS((flags & ~(LINKER_UB_UNLOCK | LINKER_UB_LOCKED | 1149 LINKER_UB_PCATCH)) == 0); 1150 if ((flags & LINKER_UB_LOCKED) != 0) 1151 sx_assert(&kld_sx, SA_XLOCKED); 1152 1153 if ((flags & LINKER_UB_LOCKED) == 0) 1154 sx_xlock(&kld_sx); 1155 while (kld_busy > 0) { 1156 if (kld_busy_owner == curthread) 1157 break; 1158 error = sx_sleep(&kld_busy, &kld_sx, 1159 (flags & LINKER_UB_PCATCH) != 0 ? PCATCH : 0, 1160 "kldbusy", 0); 1161 if (error != 0) { 1162 if ((flags & LINKER_UB_UNLOCK) != 0) 1163 sx_xunlock(&kld_sx); 1164 return (error); 1165 } 1166 } 1167 kld_busy++; 1168 kld_busy_owner = curthread; 1169 if ((flags & LINKER_UB_UNLOCK) != 0) 1170 sx_xunlock(&kld_sx); 1171 return (0); 1172 } 1173 1174 void 1175 linker_kldload_unbusy(int flags) 1176 { 1177 MPASS((flags & ~LINKER_UB_LOCKED) == 0); 1178 if ((flags & LINKER_UB_LOCKED) != 0) 1179 sx_assert(&kld_sx, SA_XLOCKED); 1180 1181 if ((flags & LINKER_UB_LOCKED) == 0) 1182 sx_xlock(&kld_sx); 1183 MPASS(kld_busy > 0); 1184 if (kld_busy_owner != curthread) 1185 panic("linker_kldload_unbusy done by not owning thread %p", 1186 kld_busy_owner); 1187 kld_busy--; 1188 if (kld_busy == 0) { 1189 kld_busy_owner = NULL; 1190 wakeup(&kld_busy); 1191 } 1192 sx_xunlock(&kld_sx); 1193 } 1194 1195 /* 1196 * Syscalls. 1197 */ 1198 int 1199 kern_kldload(struct thread *td, const char *file, int *fileid) 1200 { 1201 const char *kldname, *modname; 1202 linker_file_t lf; 1203 int error; 1204 1205 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1206 return (error); 1207 1208 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 1209 return (error); 1210 1211 /* 1212 * If file does not contain a qualified name or any dot in it 1213 * (kldname.ko, or kldname.ver.ko) treat it as an interface 1214 * name. 1215 */ 1216 if (strchr(file, '/') || strchr(file, '.')) { 1217 kldname = file; 1218 modname = NULL; 1219 } else { 1220 kldname = NULL; 1221 modname = file; 1222 } 1223 1224 error = linker_kldload_busy(LINKER_UB_PCATCH); 1225 if (error != 0) { 1226 sx_xunlock(&kld_sx); 1227 return (error); 1228 } 1229 1230 /* 1231 * It is possible that kldloaded module will attach a new ifnet, 1232 * so vnet context must be set when this ocurs. 1233 */ 1234 CURVNET_SET(TD_TO_VNET(td)); 1235 1236 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 1237 CURVNET_RESTORE(); 1238 1239 if (error == 0) { 1240 lf->userrefs++; 1241 if (fileid != NULL) 1242 *fileid = lf->id; 1243 } 1244 linker_kldload_unbusy(LINKER_UB_LOCKED); 1245 return (error); 1246 } 1247 1248 int 1249 sys_kldload(struct thread *td, struct kldload_args *uap) 1250 { 1251 char *pathname = NULL; 1252 int error, fileid; 1253 1254 td->td_retval[0] = -1; 1255 1256 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1257 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 1258 if (error == 0) { 1259 error = kern_kldload(td, pathname, &fileid); 1260 if (error == 0) 1261 td->td_retval[0] = fileid; 1262 } 1263 free(pathname, M_TEMP); 1264 return (error); 1265 } 1266 1267 int 1268 kern_kldunload(struct thread *td, int fileid, int flags) 1269 { 1270 linker_file_t lf; 1271 int error = 0; 1272 1273 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1274 return (error); 1275 1276 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 1277 return (error); 1278 1279 error = linker_kldload_busy(LINKER_UB_PCATCH); 1280 if (error != 0) { 1281 sx_xunlock(&kld_sx); 1282 return (error); 1283 } 1284 1285 CURVNET_SET(TD_TO_VNET(td)); 1286 lf = linker_find_file_by_id(fileid); 1287 if (lf) { 1288 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 1289 1290 if (lf->userrefs == 0) { 1291 /* 1292 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 1293 */ 1294 printf("kldunload: attempt to unload file that was" 1295 " loaded by the kernel\n"); 1296 error = EBUSY; 1297 } else if (lf->refs > 1) { 1298 error = EBUSY; 1299 } else { 1300 lf->userrefs--; 1301 error = linker_file_unload(lf, flags); 1302 if (error) 1303 lf->userrefs++; 1304 } 1305 } else 1306 error = ENOENT; 1307 CURVNET_RESTORE(); 1308 linker_kldload_unbusy(LINKER_UB_LOCKED); 1309 return (error); 1310 } 1311 1312 int 1313 sys_kldunload(struct thread *td, struct kldunload_args *uap) 1314 { 1315 1316 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 1317 } 1318 1319 int 1320 sys_kldunloadf(struct thread *td, struct kldunloadf_args *uap) 1321 { 1322 1323 if (uap->flags != LINKER_UNLOAD_NORMAL && 1324 uap->flags != LINKER_UNLOAD_FORCE) 1325 return (EINVAL); 1326 return (kern_kldunload(td, uap->fileid, uap->flags)); 1327 } 1328 1329 int 1330 sys_kldfind(struct thread *td, struct kldfind_args *uap) 1331 { 1332 char *pathname; 1333 const char *filename; 1334 linker_file_t lf; 1335 int error; 1336 1337 #ifdef MAC 1338 error = mac_kld_check_stat(td->td_ucred); 1339 if (error) 1340 return (error); 1341 #endif 1342 1343 td->td_retval[0] = -1; 1344 1345 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1346 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1347 goto out; 1348 1349 filename = linker_basename(pathname); 1350 sx_xlock(&kld_sx); 1351 lf = linker_find_file_by_name(filename); 1352 if (lf) 1353 td->td_retval[0] = lf->id; 1354 else 1355 error = ENOENT; 1356 sx_xunlock(&kld_sx); 1357 out: 1358 free(pathname, M_TEMP); 1359 return (error); 1360 } 1361 1362 int 1363 sys_kldnext(struct thread *td, struct kldnext_args *uap) 1364 { 1365 linker_file_t lf; 1366 int error = 0; 1367 1368 #ifdef MAC 1369 error = mac_kld_check_stat(td->td_ucred); 1370 if (error) 1371 return (error); 1372 #endif 1373 1374 sx_xlock(&kld_sx); 1375 if (uap->fileid == 0) 1376 lf = TAILQ_FIRST(&linker_files); 1377 else { 1378 lf = linker_find_file_by_id(uap->fileid); 1379 if (lf == NULL) { 1380 error = ENOENT; 1381 goto out; 1382 } 1383 lf = TAILQ_NEXT(lf, link); 1384 } 1385 1386 /* Skip partially loaded files. */ 1387 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1388 lf = TAILQ_NEXT(lf, link); 1389 1390 if (lf) 1391 td->td_retval[0] = lf->id; 1392 else 1393 td->td_retval[0] = 0; 1394 out: 1395 sx_xunlock(&kld_sx); 1396 return (error); 1397 } 1398 1399 int 1400 sys_kldstat(struct thread *td, struct kldstat_args *uap) 1401 { 1402 struct kld_file_stat *stat; 1403 int error, version; 1404 1405 /* 1406 * Check the version of the user's structure. 1407 */ 1408 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) 1409 != 0) 1410 return (error); 1411 if (version != sizeof(struct kld_file_stat_1) && 1412 version != sizeof(struct kld_file_stat)) 1413 return (EINVAL); 1414 1415 stat = malloc(sizeof(*stat), M_TEMP, M_WAITOK | M_ZERO); 1416 error = kern_kldstat(td, uap->fileid, stat); 1417 if (error == 0) 1418 error = copyout(stat, uap->stat, version); 1419 free(stat, M_TEMP); 1420 return (error); 1421 } 1422 1423 int 1424 kern_kldstat(struct thread *td, int fileid, struct kld_file_stat *stat) 1425 { 1426 linker_file_t lf; 1427 int namelen; 1428 #ifdef MAC 1429 int error; 1430 1431 error = mac_kld_check_stat(td->td_ucred); 1432 if (error) 1433 return (error); 1434 #endif 1435 1436 sx_xlock(&kld_sx); 1437 lf = linker_find_file_by_id(fileid); 1438 if (lf == NULL) { 1439 sx_xunlock(&kld_sx); 1440 return (ENOENT); 1441 } 1442 1443 /* Version 1 fields: */ 1444 namelen = strlen(lf->filename) + 1; 1445 if (namelen > sizeof(stat->name)) 1446 namelen = sizeof(stat->name); 1447 bcopy(lf->filename, &stat->name[0], namelen); 1448 stat->refs = lf->refs; 1449 stat->id = lf->id; 1450 stat->address = lf->address; 1451 stat->size = lf->size; 1452 /* Version 2 fields: */ 1453 namelen = strlen(lf->pathname) + 1; 1454 if (namelen > sizeof(stat->pathname)) 1455 namelen = sizeof(stat->pathname); 1456 bcopy(lf->pathname, &stat->pathname[0], namelen); 1457 sx_xunlock(&kld_sx); 1458 1459 td->td_retval[0] = 0; 1460 return (0); 1461 } 1462 1463 #ifdef DDB 1464 DB_COMMAND_FLAGS(kldstat, db_kldstat, DB_CMD_MEMSAFE) 1465 { 1466 linker_file_t lf; 1467 1468 #define POINTER_WIDTH ((int)(sizeof(void *) * 2 + 2)) 1469 db_printf("Id Refs Address%*c Size Name\n", POINTER_WIDTH - 7, ' '); 1470 #undef POINTER_WIDTH 1471 TAILQ_FOREACH(lf, &linker_files, link) { 1472 if (db_pager_quit) 1473 return; 1474 db_printf("%2d %4d %p %-8zx %s\n", lf->id, lf->refs, 1475 lf->address, lf->size, lf->filename); 1476 } 1477 } 1478 #endif /* DDB */ 1479 1480 int 1481 sys_kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1482 { 1483 linker_file_t lf; 1484 module_t mp; 1485 int error = 0; 1486 1487 #ifdef MAC 1488 error = mac_kld_check_stat(td->td_ucred); 1489 if (error) 1490 return (error); 1491 #endif 1492 1493 sx_xlock(&kld_sx); 1494 lf = linker_find_file_by_id(uap->fileid); 1495 if (lf) { 1496 MOD_SLOCK; 1497 mp = TAILQ_FIRST(&lf->modules); 1498 if (mp != NULL) 1499 td->td_retval[0] = module_getid(mp); 1500 else 1501 td->td_retval[0] = 0; 1502 MOD_SUNLOCK; 1503 } else 1504 error = ENOENT; 1505 sx_xunlock(&kld_sx); 1506 return (error); 1507 } 1508 1509 int 1510 sys_kldsym(struct thread *td, struct kldsym_args *uap) 1511 { 1512 char *symstr = NULL; 1513 c_linker_sym_t sym; 1514 linker_symval_t symval; 1515 linker_file_t lf; 1516 struct kld_sym_lookup lookup; 1517 int error = 0; 1518 1519 #ifdef MAC 1520 error = mac_kld_check_stat(td->td_ucred); 1521 if (error) 1522 return (error); 1523 #endif 1524 1525 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1526 return (error); 1527 if (lookup.version != sizeof(lookup) || 1528 uap->cmd != KLDSYM_LOOKUP) 1529 return (EINVAL); 1530 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1531 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1532 goto out; 1533 sx_xlock(&kld_sx); 1534 if (uap->fileid != 0) { 1535 lf = linker_find_file_by_id(uap->fileid); 1536 if (lf == NULL) 1537 error = ENOENT; 1538 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1539 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1540 lookup.symvalue = (uintptr_t) symval.value; 1541 lookup.symsize = symval.size; 1542 error = copyout(&lookup, uap->data, sizeof(lookup)); 1543 } else 1544 error = ENOENT; 1545 } else { 1546 TAILQ_FOREACH(lf, &linker_files, link) { 1547 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1548 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1549 lookup.symvalue = (uintptr_t)symval.value; 1550 lookup.symsize = symval.size; 1551 error = copyout(&lookup, uap->data, 1552 sizeof(lookup)); 1553 break; 1554 } 1555 } 1556 if (lf == NULL) 1557 error = ENOENT; 1558 } 1559 sx_xunlock(&kld_sx); 1560 out: 1561 free(symstr, M_TEMP); 1562 return (error); 1563 } 1564 1565 /* 1566 * Preloaded module support 1567 */ 1568 1569 static modlist_t 1570 modlist_lookup(const char *name, int ver) 1571 { 1572 modlist_t mod; 1573 1574 TAILQ_FOREACH(mod, &found_modules, link) { 1575 if (strcmp(mod->name, name) == 0 && 1576 (ver == 0 || mod->version == ver)) 1577 return (mod); 1578 } 1579 return (NULL); 1580 } 1581 1582 static modlist_t 1583 modlist_lookup2(const char *name, const struct mod_depend *verinfo) 1584 { 1585 modlist_t mod, bestmod; 1586 int ver; 1587 1588 if (verinfo == NULL) 1589 return (modlist_lookup(name, 0)); 1590 bestmod = NULL; 1591 TAILQ_FOREACH(mod, &found_modules, link) { 1592 if (strcmp(mod->name, name) != 0) 1593 continue; 1594 ver = mod->version; 1595 if (ver == verinfo->md_ver_preferred) 1596 return (mod); 1597 if (ver >= verinfo->md_ver_minimum && 1598 ver <= verinfo->md_ver_maximum && 1599 (bestmod == NULL || ver > bestmod->version)) 1600 bestmod = mod; 1601 } 1602 return (bestmod); 1603 } 1604 1605 static modlist_t 1606 modlist_newmodule(const char *modname, int version, linker_file_t container) 1607 { 1608 modlist_t mod; 1609 1610 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1611 if (mod == NULL) 1612 panic("no memory for module list"); 1613 mod->container = container; 1614 mod->name = modname; 1615 mod->version = version; 1616 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1617 return (mod); 1618 } 1619 1620 static void 1621 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1622 struct mod_metadata **stop, int preload) 1623 { 1624 struct mod_metadata *mp, **mdp; 1625 const char *modname; 1626 int ver; 1627 1628 for (mdp = start; mdp < stop; mdp++) { 1629 mp = *mdp; 1630 if (mp->md_type != MDT_VERSION) 1631 continue; 1632 modname = mp->md_cval; 1633 ver = ((const struct mod_version *)mp->md_data)->mv_version; 1634 if (modlist_lookup(modname, ver) != NULL) { 1635 printf("module %s already present!\n", modname); 1636 /* XXX what can we do? this is a build error. :-( */ 1637 continue; 1638 } 1639 modlist_newmodule(modname, ver, lf); 1640 } 1641 } 1642 1643 static void 1644 linker_preload(void *arg) 1645 { 1646 caddr_t modptr; 1647 const char *modname, *nmodname; 1648 char *modtype; 1649 linker_file_t lf, nlf; 1650 linker_class_t lc; 1651 int error; 1652 linker_file_list_t loaded_files; 1653 linker_file_list_t depended_files; 1654 struct mod_metadata *mp, *nmp; 1655 struct mod_metadata **start, **stop, **mdp, **nmdp; 1656 const struct mod_depend *verinfo; 1657 int nver; 1658 int resolves; 1659 modlist_t mod; 1660 struct sysinit **si_start, **si_stop; 1661 1662 TAILQ_INIT(&loaded_files); 1663 TAILQ_INIT(&depended_files); 1664 TAILQ_INIT(&found_modules); 1665 error = 0; 1666 1667 modptr = NULL; 1668 sx_xlock(&kld_sx); 1669 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1670 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1671 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1672 if (modname == NULL) { 1673 printf("Preloaded module at %p does not have a" 1674 " name!\n", modptr); 1675 continue; 1676 } 1677 if (modtype == NULL) { 1678 printf("Preloaded module at %p does not have a type!\n", 1679 modptr); 1680 continue; 1681 } 1682 if (bootverbose) 1683 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1684 modptr); 1685 lf = NULL; 1686 TAILQ_FOREACH(lc, &classes, link) { 1687 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1688 if (!error) 1689 break; 1690 lf = NULL; 1691 } 1692 if (lf) 1693 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1694 } 1695 1696 /* 1697 * First get a list of stuff in the kernel. 1698 */ 1699 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1700 &stop, NULL) == 0) 1701 linker_addmodules(linker_kernel_file, start, stop, 1); 1702 1703 /* 1704 * This is a once-off kinky bubble sort to resolve relocation 1705 * dependency requirements. 1706 */ 1707 restart: 1708 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1709 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1710 &stop, NULL); 1711 /* 1712 * First, look to see if we would successfully link with this 1713 * stuff. 1714 */ 1715 resolves = 1; /* unless we know otherwise */ 1716 if (!error) { 1717 for (mdp = start; mdp < stop; mdp++) { 1718 mp = *mdp; 1719 if (mp->md_type != MDT_DEPEND) 1720 continue; 1721 modname = mp->md_cval; 1722 verinfo = mp->md_data; 1723 for (nmdp = start; nmdp < stop; nmdp++) { 1724 nmp = *nmdp; 1725 if (nmp->md_type != MDT_VERSION) 1726 continue; 1727 nmodname = nmp->md_cval; 1728 if (strcmp(modname, nmodname) == 0) 1729 break; 1730 } 1731 if (nmdp < stop) /* it's a self reference */ 1732 continue; 1733 1734 /* 1735 * ok, the module isn't here yet, we 1736 * are not finished 1737 */ 1738 if (modlist_lookup2(modname, verinfo) == NULL) 1739 resolves = 0; 1740 } 1741 } 1742 /* 1743 * OK, if we found our modules, we can link. So, "provide" 1744 * the modules inside and add it to the end of the link order 1745 * list. 1746 */ 1747 if (resolves) { 1748 if (!error) { 1749 for (mdp = start; mdp < stop; mdp++) { 1750 mp = *mdp; 1751 if (mp->md_type != MDT_VERSION) 1752 continue; 1753 modname = mp->md_cval; 1754 nver = ((const struct mod_version *) 1755 mp->md_data)->mv_version; 1756 if (modlist_lookup(modname, 1757 nver) != NULL) { 1758 printf("module %s already" 1759 " present!\n", modname); 1760 TAILQ_REMOVE(&loaded_files, 1761 lf, loaded); 1762 linker_file_unload(lf, 1763 LINKER_UNLOAD_FORCE); 1764 /* we changed tailq next ptr */ 1765 goto restart; 1766 } 1767 modlist_newmodule(modname, nver, lf); 1768 } 1769 } 1770 TAILQ_REMOVE(&loaded_files, lf, loaded); 1771 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1772 /* 1773 * Since we provided modules, we need to restart the 1774 * sort so that the previous files that depend on us 1775 * have a chance. Also, we've busted the tailq next 1776 * pointer with the REMOVE. 1777 */ 1778 goto restart; 1779 } 1780 } 1781 1782 /* 1783 * At this point, we check to see what could not be resolved.. 1784 */ 1785 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1786 TAILQ_REMOVE(&loaded_files, lf, loaded); 1787 printf("KLD file %s is missing dependencies\n", lf->filename); 1788 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1789 } 1790 1791 /* 1792 * We made it. Finish off the linking in the order we determined. 1793 */ 1794 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1795 if (linker_kernel_file) { 1796 linker_kernel_file->refs++; 1797 linker_file_add_dependency(lf, linker_kernel_file); 1798 } 1799 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1800 &stop, NULL); 1801 if (!error) { 1802 for (mdp = start; mdp < stop; mdp++) { 1803 mp = *mdp; 1804 if (mp->md_type != MDT_DEPEND) 1805 continue; 1806 modname = mp->md_cval; 1807 verinfo = mp->md_data; 1808 mod = modlist_lookup2(modname, verinfo); 1809 if (mod == NULL) { 1810 printf("KLD file %s - cannot find " 1811 "dependency \"%s\"\n", 1812 lf->filename, modname); 1813 goto fail; 1814 } 1815 /* Don't count self-dependencies */ 1816 if (lf == mod->container) 1817 continue; 1818 mod->container->refs++; 1819 linker_file_add_dependency(lf, mod->container); 1820 } 1821 } 1822 /* 1823 * Now do relocation etc using the symbol search paths 1824 * established by the dependencies 1825 */ 1826 error = LINKER_LINK_PRELOAD_FINISH(lf); 1827 if (error) { 1828 printf("KLD file %s - could not finalize loading\n", 1829 lf->filename); 1830 goto fail; 1831 } 1832 linker_file_register_modules(lf); 1833 if (!TAILQ_EMPTY(&lf->modules)) 1834 lf->flags |= LINKER_FILE_MODULES; 1835 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1836 &si_stop, NULL) == 0) 1837 sysinit_add(si_start, si_stop); 1838 linker_file_register_sysctls(lf, true); 1839 lf->flags |= LINKER_FILE_LINKED; 1840 continue; 1841 fail: 1842 TAILQ_REMOVE(&depended_files, lf, loaded); 1843 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1844 } 1845 sx_xunlock(&kld_sx); 1846 /* woohoo! we made it! */ 1847 } 1848 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, NULL); 1849 1850 static void 1851 linker_mountroot(void *arg __unused) 1852 { 1853 linker_file_t lf; 1854 1855 sx_xlock(&kld_sx); 1856 TAILQ_FOREACH (lf, &linker_files, link) { 1857 linker_ctf_load_file(lf); 1858 } 1859 sx_xunlock(&kld_sx); 1860 } 1861 EVENTHANDLER_DEFINE(mountroot, linker_mountroot, NULL, 0); 1862 1863 /* 1864 * Handle preload files that failed to load any modules. 1865 */ 1866 static void 1867 linker_preload_finish(void *arg) 1868 { 1869 linker_file_t lf, nlf; 1870 1871 sx_xlock(&kld_sx); 1872 TAILQ_FOREACH_SAFE(lf, &linker_files, link, nlf) { 1873 if (lf == linker_kernel_file) 1874 continue; 1875 1876 /* 1877 * If all of the modules in this file failed to load, unload 1878 * the file and return an error of ENOEXEC. (Parity with 1879 * linker_load_file.) 1880 */ 1881 if ((lf->flags & LINKER_FILE_MODULES) != 0 && 1882 TAILQ_EMPTY(&lf->modules)) { 1883 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1884 continue; 1885 } 1886 1887 lf->flags &= ~LINKER_FILE_MODULES; 1888 lf->userrefs++; /* so we can (try to) kldunload it */ 1889 } 1890 sx_xunlock(&kld_sx); 1891 } 1892 1893 /* 1894 * Attempt to run after all DECLARE_MODULE SYSINITs. Unfortunately they can be 1895 * scheduled at any subsystem and order, so run this as late as possible. init 1896 * becomes runnable in SI_SUB_KTHREAD_INIT, so go slightly before that. 1897 */ 1898 SYSINIT(preload_finish, SI_SUB_KTHREAD_INIT - 100, SI_ORDER_MIDDLE, 1899 linker_preload_finish, NULL); 1900 1901 /* 1902 * Search for a not-loaded module by name. 1903 * 1904 * Modules may be found in the following locations: 1905 * 1906 * - preloaded (result is just the module name) - on disk (result is full path 1907 * to module) 1908 * 1909 * If the module name is qualified in any way (contains path, etc.) the we 1910 * simply return a copy of it. 1911 * 1912 * The search path can be manipulated via sysctl. Note that we use the ';' 1913 * character as a separator to be consistent with the bootloader. 1914 */ 1915 1916 static char linker_hintfile[] = "linker.hints"; 1917 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1918 1919 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RWTUN, linker_path, 1920 sizeof(linker_path), "module load search path"); 1921 1922 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1923 1924 static const char * const linker_ext_list[] = { 1925 "", 1926 ".ko", 1927 NULL 1928 }; 1929 1930 /* 1931 * Check if file actually exists either with or without extension listed in 1932 * the linker_ext_list. (probably should be generic for the rest of the 1933 * kernel) 1934 */ 1935 static char * 1936 linker_lookup_file(const char *path, int pathlen, const char *name, 1937 int namelen, struct vattr *vap) 1938 { 1939 struct nameidata nd; 1940 struct thread *td = curthread; /* XXX */ 1941 const char * const *cpp, *sep; 1942 char *result; 1943 int error, len, extlen, reclen, flags; 1944 __enum_uint8(vtype) type; 1945 1946 extlen = 0; 1947 for (cpp = linker_ext_list; *cpp; cpp++) { 1948 len = strlen(*cpp); 1949 if (len > extlen) 1950 extlen = len; 1951 } 1952 extlen++; /* trailing '\0' */ 1953 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1954 1955 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1956 result = malloc(reclen, M_LINKER, M_WAITOK); 1957 for (cpp = linker_ext_list; *cpp; cpp++) { 1958 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1959 namelen, name, *cpp); 1960 /* 1961 * Attempt to open the file, and return the path if 1962 * we succeed and it's a regular file. 1963 */ 1964 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result); 1965 flags = FREAD; 1966 error = vn_open(&nd, &flags, 0, NULL); 1967 if (error == 0) { 1968 NDFREE_PNBUF(&nd); 1969 type = nd.ni_vp->v_type; 1970 if (vap) 1971 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred); 1972 VOP_UNLOCK(nd.ni_vp); 1973 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1974 if (type == VREG) 1975 return (result); 1976 } 1977 } 1978 free(result, M_LINKER); 1979 return (NULL); 1980 } 1981 1982 #define INT_ALIGN(base, ptr) ptr = \ 1983 (base) + roundup2((ptr) - (base), sizeof(int)) 1984 1985 /* 1986 * Lookup KLD which contains requested module in the "linker.hints" file. If 1987 * version specification is available, then try to find the best KLD. 1988 * Otherwise just find the latest one. 1989 */ 1990 static char * 1991 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1992 int modnamelen, const struct mod_depend *verinfo) 1993 { 1994 struct thread *td = curthread; /* XXX */ 1995 struct ucred *cred = td ? td->td_ucred : NULL; 1996 struct nameidata nd; 1997 struct vattr vattr, mattr; 1998 const char *best, *sep; 1999 u_char *hints = NULL; 2000 u_char *cp, *recptr, *bufend, *result, *pathbuf; 2001 int error, ival, bestver, *intp, found, flags, clen, blen; 2002 ssize_t reclen; 2003 2004 result = NULL; 2005 bestver = found = 0; 2006 2007 sep = (path[pathlen - 1] != '/') ? "/" : ""; 2008 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 2009 strlen(sep) + 1; 2010 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 2011 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 2012 linker_hintfile); 2013 2014 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf); 2015 flags = FREAD; 2016 error = vn_open(&nd, &flags, 0, NULL); 2017 if (error) 2018 goto bad; 2019 NDFREE_PNBUF(&nd); 2020 if (nd.ni_vp->v_type != VREG) 2021 goto bad; 2022 best = cp = NULL; 2023 error = VOP_GETATTR(nd.ni_vp, &vattr, cred); 2024 if (error) 2025 goto bad; 2026 /* 2027 * XXX: we need to limit this number to some reasonable value 2028 */ 2029 if (vattr.va_size > LINKER_HINTS_MAX) { 2030 printf("linker.hints file too large %ld\n", (long)vattr.va_size); 2031 goto bad; 2032 } 2033 if (vattr.va_size < sizeof(ival)) { 2034 printf("linker.hints file truncated\n"); 2035 goto bad; 2036 } 2037 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 2038 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 2039 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 2040 if (error) 2041 goto bad; 2042 VOP_UNLOCK(nd.ni_vp); 2043 vn_close(nd.ni_vp, FREAD, cred, td); 2044 nd.ni_vp = NULL; 2045 if (reclen != 0) { 2046 printf("can't read %zd\n", reclen); 2047 goto bad; 2048 } 2049 intp = (int *)hints; 2050 ival = *intp++; 2051 if (ival != LINKER_HINTS_VERSION) { 2052 printf("linker.hints file version mismatch %d\n", ival); 2053 goto bad; 2054 } 2055 bufend = hints + vattr.va_size; 2056 recptr = (u_char *)intp; 2057 clen = blen = 0; 2058 while (recptr < bufend && !found) { 2059 intp = (int *)recptr; 2060 reclen = *intp++; 2061 ival = *intp++; 2062 cp = (char *)intp; 2063 switch (ival) { 2064 case MDT_VERSION: 2065 clen = *cp++; 2066 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 2067 break; 2068 cp += clen; 2069 INT_ALIGN(hints, cp); 2070 ival = *(int *)cp; 2071 cp += sizeof(int); 2072 clen = *cp++; 2073 if (verinfo == NULL || 2074 ival == verinfo->md_ver_preferred) { 2075 found = 1; 2076 break; 2077 } 2078 if (ival >= verinfo->md_ver_minimum && 2079 ival <= verinfo->md_ver_maximum && 2080 ival > bestver) { 2081 bestver = ival; 2082 best = cp; 2083 blen = clen; 2084 } 2085 break; 2086 default: 2087 break; 2088 } 2089 recptr += reclen + sizeof(int); 2090 } 2091 /* 2092 * Finally check if KLD is in the place 2093 */ 2094 if (found) 2095 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 2096 else if (best) 2097 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 2098 2099 /* 2100 * KLD is newer than hints file. What we should do now? 2101 */ 2102 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 2103 printf("warning: KLD '%s' is newer than the linker.hints" 2104 " file\n", result); 2105 bad: 2106 free(pathbuf, M_LINKER); 2107 if (hints) 2108 free(hints, M_TEMP); 2109 if (nd.ni_vp != NULL) { 2110 VOP_UNLOCK(nd.ni_vp); 2111 vn_close(nd.ni_vp, FREAD, cred, td); 2112 } 2113 /* 2114 * If nothing found or hints is absent - fallback to the old 2115 * way by using "kldname[.ko]" as module name. 2116 */ 2117 if (!found && !bestver && result == NULL) 2118 result = linker_lookup_file(path, pathlen, modname, 2119 modnamelen, NULL); 2120 return (result); 2121 } 2122 2123 /* 2124 * Lookup KLD which contains requested module in the all directories. 2125 */ 2126 static char * 2127 linker_search_module(const char *modname, int modnamelen, 2128 const struct mod_depend *verinfo) 2129 { 2130 char *cp, *ep, *result; 2131 2132 /* 2133 * traverse the linker path 2134 */ 2135 for (cp = linker_path; *cp; cp = ep + 1) { 2136 /* find the end of this component */ 2137 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 2138 result = linker_hints_lookup(cp, ep - cp, modname, 2139 modnamelen, verinfo); 2140 if (result != NULL) 2141 return (result); 2142 if (*ep == 0) 2143 break; 2144 } 2145 return (NULL); 2146 } 2147 2148 /* 2149 * Search for module in all directories listed in the linker_path. 2150 */ 2151 static char * 2152 linker_search_kld(const char *name) 2153 { 2154 char *cp, *ep, *result; 2155 int len; 2156 2157 /* qualified at all? */ 2158 if (strchr(name, '/')) 2159 return (strdup(name, M_LINKER)); 2160 2161 /* traverse the linker path */ 2162 len = strlen(name); 2163 for (ep = linker_path; *ep; ep++) { 2164 cp = ep; 2165 /* find the end of this component */ 2166 for (; *ep != 0 && *ep != ';'; ep++); 2167 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 2168 if (result != NULL) 2169 return (result); 2170 } 2171 return (NULL); 2172 } 2173 2174 static const char * 2175 linker_basename(const char *path) 2176 { 2177 const char *filename; 2178 2179 filename = strrchr(path, '/'); 2180 if (filename == NULL) 2181 return path; 2182 if (filename[1]) 2183 filename++; 2184 return (filename); 2185 } 2186 2187 #ifdef HWPMC_HOOKS 2188 /* 2189 * Inform hwpmc about the set of kernel modules currently loaded. 2190 */ 2191 void * 2192 linker_hwpmc_list_objects(void) 2193 { 2194 linker_file_t lf; 2195 struct pmckern_map_in *kobase; 2196 int i, nmappings; 2197 2198 nmappings = 0; 2199 sx_slock(&kld_sx); 2200 TAILQ_FOREACH(lf, &linker_files, link) 2201 nmappings++; 2202 2203 /* Allocate nmappings + 1 entries. */ 2204 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in), 2205 M_LINKER, M_WAITOK | M_ZERO); 2206 i = 0; 2207 TAILQ_FOREACH(lf, &linker_files, link) { 2208 /* Save the info for this linker file. */ 2209 kobase[i].pm_file = lf->pathname; 2210 kobase[i].pm_address = (uintptr_t)lf->address; 2211 i++; 2212 } 2213 sx_sunlock(&kld_sx); 2214 2215 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?")); 2216 2217 /* The last entry of the malloced area comprises of all zeros. */ 2218 KASSERT(kobase[i].pm_file == NULL, 2219 ("linker_hwpmc_list_objects: last object not NULL")); 2220 2221 return ((void *)kobase); 2222 } 2223 #endif 2224 2225 /* check if root file system is not mounted */ 2226 static bool 2227 linker_root_mounted(void) 2228 { 2229 struct pwd *pwd; 2230 bool ret; 2231 2232 if (rootvnode == NULL) 2233 return (false); 2234 2235 pwd = pwd_hold(curthread); 2236 ret = pwd->pwd_rdir != NULL; 2237 pwd_drop(pwd); 2238 return (ret); 2239 } 2240 2241 /* 2242 * Find a file which contains given module and load it, if "parent" is not 2243 * NULL, register a reference to it. 2244 */ 2245 static int 2246 linker_load_module(const char *kldname, const char *modname, 2247 struct linker_file *parent, const struct mod_depend *verinfo, 2248 struct linker_file **lfpp) 2249 { 2250 linker_file_t lfdep; 2251 const char *filename; 2252 char *pathname; 2253 int error; 2254 2255 sx_assert(&kld_sx, SA_XLOCKED); 2256 if (modname == NULL) { 2257 /* 2258 * We have to load KLD 2259 */ 2260 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 2261 " is not NULL")); 2262 if (!linker_root_mounted()) 2263 return (ENXIO); 2264 pathname = linker_search_kld(kldname); 2265 } else { 2266 if (modlist_lookup2(modname, verinfo) != NULL) 2267 return (EEXIST); 2268 if (!linker_root_mounted()) 2269 return (ENXIO); 2270 if (kldname != NULL) 2271 pathname = strdup(kldname, M_LINKER); 2272 else 2273 /* 2274 * Need to find a KLD with required module 2275 */ 2276 pathname = linker_search_module(modname, 2277 strlen(modname), verinfo); 2278 } 2279 if (pathname == NULL) 2280 return (ENOENT); 2281 2282 /* 2283 * Can't load more than one file with the same basename XXX: 2284 * Actually it should be possible to have multiple KLDs with 2285 * the same basename but different path because they can 2286 * provide different versions of the same modules. 2287 */ 2288 filename = linker_basename(pathname); 2289 if (linker_find_file_by_name(filename)) 2290 error = EEXIST; 2291 else do { 2292 error = linker_load_file(pathname, &lfdep); 2293 if (error) 2294 break; 2295 if (modname && verinfo && 2296 modlist_lookup2(modname, verinfo) == NULL) { 2297 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 2298 error = ENOENT; 2299 break; 2300 } 2301 if (parent) 2302 linker_file_add_dependency(parent, lfdep); 2303 if (lfpp) 2304 *lfpp = lfdep; 2305 } while (0); 2306 free(pathname, M_LINKER); 2307 return (error); 2308 } 2309 2310 /* 2311 * This routine is responsible for finding dependencies of userland initiated 2312 * kldload(2)'s of files. 2313 */ 2314 int 2315 linker_load_dependencies(linker_file_t lf) 2316 { 2317 linker_file_t lfdep; 2318 struct mod_metadata **start, **stop, **mdp, **nmdp; 2319 struct mod_metadata *mp, *nmp; 2320 const struct mod_depend *verinfo; 2321 modlist_t mod; 2322 const char *modname, *nmodname; 2323 int ver, error = 0; 2324 2325 /* 2326 * All files are dependent on /kernel. 2327 */ 2328 sx_assert(&kld_sx, SA_XLOCKED); 2329 if (linker_kernel_file) { 2330 linker_kernel_file->refs++; 2331 linker_file_add_dependency(lf, linker_kernel_file); 2332 } 2333 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 2334 NULL) != 0) 2335 return (0); 2336 for (mdp = start; mdp < stop; mdp++) { 2337 mp = *mdp; 2338 if (mp->md_type != MDT_VERSION) 2339 continue; 2340 modname = mp->md_cval; 2341 ver = ((const struct mod_version *)mp->md_data)->mv_version; 2342 mod = modlist_lookup(modname, ver); 2343 if (mod != NULL) { 2344 printf("interface %s.%d already present in the KLD" 2345 " '%s'!\n", modname, ver, 2346 mod->container->filename); 2347 return (EEXIST); 2348 } 2349 } 2350 2351 for (mdp = start; mdp < stop; mdp++) { 2352 mp = *mdp; 2353 if (mp->md_type != MDT_DEPEND) 2354 continue; 2355 modname = mp->md_cval; 2356 verinfo = mp->md_data; 2357 nmodname = NULL; 2358 for (nmdp = start; nmdp < stop; nmdp++) { 2359 nmp = *nmdp; 2360 if (nmp->md_type != MDT_VERSION) 2361 continue; 2362 nmodname = nmp->md_cval; 2363 if (strcmp(modname, nmodname) == 0) 2364 break; 2365 } 2366 if (nmdp < stop)/* early exit, it's a self reference */ 2367 continue; 2368 mod = modlist_lookup2(modname, verinfo); 2369 if (mod) { /* woohoo, it's loaded already */ 2370 lfdep = mod->container; 2371 lfdep->refs++; 2372 linker_file_add_dependency(lf, lfdep); 2373 continue; 2374 } 2375 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 2376 if (error) { 2377 printf("KLD %s: depends on %s - not available or" 2378 " version mismatch\n", lf->filename, modname); 2379 break; 2380 } 2381 } 2382 2383 if (error) 2384 return (error); 2385 linker_addmodules(lf, start, stop, 0); 2386 return (error); 2387 } 2388 2389 static int 2390 sysctl_kern_function_list_iterate(const char *name, void *opaque) 2391 { 2392 struct sysctl_req *req; 2393 2394 req = opaque; 2395 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 2396 } 2397 2398 /* 2399 * Export a nul-separated, double-nul-terminated list of all function names 2400 * in the kernel. 2401 */ 2402 static int 2403 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 2404 { 2405 linker_file_t lf; 2406 int error; 2407 2408 #ifdef MAC 2409 error = mac_kld_check_stat(req->td->td_ucred); 2410 if (error) 2411 return (error); 2412 #endif 2413 error = sysctl_wire_old_buffer(req, 0); 2414 if (error != 0) 2415 return (error); 2416 sx_xlock(&kld_sx); 2417 TAILQ_FOREACH(lf, &linker_files, link) { 2418 error = LINKER_EACH_FUNCTION_NAME(lf, 2419 sysctl_kern_function_list_iterate, req); 2420 if (error) { 2421 sx_xunlock(&kld_sx); 2422 return (error); 2423 } 2424 } 2425 sx_xunlock(&kld_sx); 2426 return (SYSCTL_OUT(req, "", 1)); 2427 } 2428 2429 SYSCTL_PROC(_kern, OID_AUTO, function_list, 2430 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 2431 sysctl_kern_function_list, "", 2432 "kernel function list"); 2433