Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/kern/link_elf.c
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1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1998-2000 Doug Rabson 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include "opt_ddb.h" 33 #include "opt_gdb.h" 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/kernel.h> 38 #include <sys/lock.h> 39 #include <sys/malloc.h> 40 #ifdef SPARSE_MAPPING 41 #include <sys/mman.h> 42 #endif 43 #include <sys/mutex.h> 44 #include <sys/mount.h> 45 #include <sys/pcpu.h> 46 #include <sys/proc.h> 47 #include <sys/namei.h> 48 #include <sys/fcntl.h> 49 #include <sys/vnode.h> 50 #include <sys/linker.h> 51 #include <sys/sysctl.h> 52 53 #include <machine/elf.h> 54 55 #include <net/vnet.h> 56 57 #include <security/mac/mac_framework.h> 58 59 #include <vm/vm.h> 60 #include <vm/vm_param.h> 61 #ifdef SPARSE_MAPPING 62 #include <vm/vm_object.h> 63 #include <vm/vm_kern.h> 64 #include <vm/vm_extern.h> 65 #endif 66 #include <vm/pmap.h> 67 #include <vm/vm_map.h> 68 69 #include <sys/link_elf.h> 70 71 #include "linker_if.h" 72 73 #define MAXSEGS 4 74 75 typedef struct elf_file { 76 struct linker_file lf; /* Common fields */ 77 int preloaded; /* Was file pre-loaded */ 78 caddr_t address; /* Relocation address */ 79 #ifdef SPARSE_MAPPING 80 vm_object_t object; /* VM object to hold file pages */ 81 #endif 82 Elf_Dyn *dynamic; /* Symbol table etc. */ 83 Elf_Hashelt nbuckets; /* DT_HASH info */ 84 Elf_Hashelt nchains; 85 const Elf_Hashelt *buckets; 86 const Elf_Hashelt *chains; 87 caddr_t hash; 88 caddr_t strtab; /* DT_STRTAB */ 89 int strsz; /* DT_STRSZ */ 90 const Elf_Sym *symtab; /* DT_SYMTAB */ 91 Elf_Addr *got; /* DT_PLTGOT */ 92 const Elf_Rel *pltrel; /* DT_JMPREL */ 93 int pltrelsize; /* DT_PLTRELSZ */ 94 const Elf_Rela *pltrela; /* DT_JMPREL */ 95 int pltrelasize; /* DT_PLTRELSZ */ 96 const Elf_Rel *rel; /* DT_REL */ 97 int relsize; /* DT_RELSZ */ 98 const Elf_Rela *rela; /* DT_RELA */ 99 int relasize; /* DT_RELASZ */ 100 caddr_t modptr; 101 const Elf_Sym *ddbsymtab; /* The symbol table we are using */ 102 long ddbsymcnt; /* Number of symbols */ 103 caddr_t ddbstrtab; /* String table */ 104 long ddbstrcnt; /* number of bytes in string table */ 105 caddr_t symbase; /* malloc'ed symbold base */ 106 caddr_t strbase; /* malloc'ed string base */ 107 caddr_t ctftab; /* CTF table */ 108 long ctfcnt; /* number of bytes in CTF table */ 109 caddr_t ctfoff; /* CTF offset table */ 110 caddr_t typoff; /* Type offset table */ 111 long typlen; /* Number of type entries. */ 112 Elf_Addr pcpu_start; /* Pre-relocation pcpu set start. */ 113 Elf_Addr pcpu_stop; /* Pre-relocation pcpu set stop. */ 114 Elf_Addr pcpu_base; /* Relocated pcpu set address. */ 115 #ifdef VIMAGE 116 Elf_Addr vnet_start; /* Pre-relocation vnet set start. */ 117 Elf_Addr vnet_stop; /* Pre-relocation vnet set stop. */ 118 Elf_Addr vnet_base; /* Relocated vnet set address. */ 119 #endif 120 #ifdef GDB 121 struct link_map gdb; /* hooks for gdb */ 122 #endif 123 } *elf_file_t; 124 125 struct elf_set { 126 Elf_Addr es_start; 127 Elf_Addr es_stop; 128 Elf_Addr es_base; 129 TAILQ_ENTRY(elf_set) es_link; 130 }; 131 132 TAILQ_HEAD(elf_set_head, elf_set); 133 134 #include <kern/kern_ctf.c> 135 136 static int link_elf_link_common_finish(linker_file_t); 137 static int link_elf_link_preload(linker_class_t cls, 138 const char *, linker_file_t *); 139 static int link_elf_link_preload_finish(linker_file_t); 140 static int link_elf_load_file(linker_class_t, const char *, 141 linker_file_t *); 142 static int link_elf_lookup_symbol(linker_file_t, const char *, 143 c_linker_sym_t *); 144 static int link_elf_lookup_debug_symbol(linker_file_t, const char *, 145 c_linker_sym_t *); 146 static int link_elf_symbol_values(linker_file_t, c_linker_sym_t, 147 linker_symval_t *); 148 static int link_elf_debug_symbol_values(linker_file_t, c_linker_sym_t, 149 linker_symval_t*); 150 static int link_elf_search_symbol(linker_file_t, caddr_t, 151 c_linker_sym_t *, long *); 152 153 static void link_elf_unload_file(linker_file_t); 154 static void link_elf_unload_preload(linker_file_t); 155 static int link_elf_lookup_set(linker_file_t, const char *, 156 void ***, void ***, int *); 157 static int link_elf_each_function_name(linker_file_t, 158 int (*)(const char *, void *), void *); 159 static int link_elf_each_function_nameval(linker_file_t, 160 linker_function_nameval_callback_t, void *); 161 static void link_elf_reloc_local(linker_file_t); 162 static long link_elf_symtab_get(linker_file_t, const Elf_Sym **); 163 static long link_elf_strtab_get(linker_file_t, caddr_t *); 164 static int elf_lookup(linker_file_t, Elf_Size, int, Elf_Addr *); 165 166 static kobj_method_t link_elf_methods[] = { 167 KOBJMETHOD(linker_lookup_symbol, link_elf_lookup_symbol), 168 KOBJMETHOD(linker_lookup_debug_symbol, link_elf_lookup_debug_symbol), 169 KOBJMETHOD(linker_symbol_values, link_elf_symbol_values), 170 KOBJMETHOD(linker_debug_symbol_values, link_elf_debug_symbol_values), 171 KOBJMETHOD(linker_search_symbol, link_elf_search_symbol), 172 KOBJMETHOD(linker_unload, link_elf_unload_file), 173 KOBJMETHOD(linker_load_file, link_elf_load_file), 174 KOBJMETHOD(linker_link_preload, link_elf_link_preload), 175 KOBJMETHOD(linker_link_preload_finish, link_elf_link_preload_finish), 176 KOBJMETHOD(linker_lookup_set, link_elf_lookup_set), 177 KOBJMETHOD(linker_each_function_name, link_elf_each_function_name), 178 KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval), 179 KOBJMETHOD(linker_ctf_get, link_elf_ctf_get), 180 KOBJMETHOD(linker_symtab_get, link_elf_symtab_get), 181 KOBJMETHOD(linker_strtab_get, link_elf_strtab_get), 182 KOBJMETHOD_END 183 }; 184 185 static struct linker_class link_elf_class = { 186 #if ELF_TARG_CLASS == ELFCLASS32 187 "elf32", 188 #else 189 "elf64", 190 #endif 191 link_elf_methods, sizeof(struct elf_file) 192 }; 193 194 static bool link_elf_leak_locals = true; 195 SYSCTL_BOOL(_debug, OID_AUTO, link_elf_leak_locals, 196 CTLFLAG_RWTUN, &link_elf_leak_locals, 0, 197 "Allow local symbols to participate in global module symbol resolution"); 198 199 typedef int (*elf_reloc_fn)(linker_file_t lf, Elf_Addr relocbase, 200 const void *data, int type, elf_lookup_fn lookup); 201 202 static int parse_dynamic(elf_file_t); 203 static int relocate_file(elf_file_t); 204 static int relocate_file1(elf_file_t ef, elf_lookup_fn lookup, 205 elf_reloc_fn reloc, bool ifuncs); 206 static int link_elf_preload_parse_symbols(elf_file_t); 207 208 static struct elf_set_head set_pcpu_list; 209 #ifdef VIMAGE 210 static struct elf_set_head set_vnet_list; 211 #endif 212 213 static void 214 elf_set_add(struct elf_set_head *list, Elf_Addr start, Elf_Addr stop, Elf_Addr base) 215 { 216 struct elf_set *set, *iter; 217 218 set = malloc(sizeof(*set), M_LINKER, M_WAITOK); 219 set->es_start = start; 220 set->es_stop = stop; 221 set->es_base = base; 222 223 TAILQ_FOREACH(iter, list, es_link) { 224 KASSERT((set->es_start < iter->es_start && set->es_stop < iter->es_stop) || 225 (set->es_start > iter->es_start && set->es_stop > iter->es_stop), 226 ("linker sets intersection: to insert: 0x%jx-0x%jx; inserted: 0x%jx-0x%jx", 227 (uintmax_t)set->es_start, (uintmax_t)set->es_stop, 228 (uintmax_t)iter->es_start, (uintmax_t)iter->es_stop)); 229 230 if (iter->es_start > set->es_start) { 231 TAILQ_INSERT_BEFORE(iter, set, es_link); 232 break; 233 } 234 } 235 236 if (iter == NULL) 237 TAILQ_INSERT_TAIL(list, set, es_link); 238 } 239 240 static int 241 elf_set_find(struct elf_set_head *list, Elf_Addr addr, Elf_Addr *start, Elf_Addr *base) 242 { 243 struct elf_set *set; 244 245 TAILQ_FOREACH(set, list, es_link) { 246 if (addr < set->es_start) 247 return (0); 248 if (addr < set->es_stop) { 249 *start = set->es_start; 250 *base = set->es_base; 251 return (1); 252 } 253 } 254 255 return (0); 256 } 257 258 static void 259 elf_set_delete(struct elf_set_head *list, Elf_Addr start) 260 { 261 struct elf_set *set; 262 263 TAILQ_FOREACH(set, list, es_link) { 264 if (start < set->es_start) 265 break; 266 if (start == set->es_start) { 267 TAILQ_REMOVE(list, set, es_link); 268 free(set, M_LINKER); 269 return; 270 } 271 } 272 KASSERT(0, ("deleting unknown linker set (start = 0x%jx)", 273 (uintmax_t)start)); 274 } 275 276 #ifdef GDB 277 static void r_debug_state(struct r_debug *, struct link_map *); 278 279 /* 280 * A list of loaded modules for GDB to use for loading symbols. 281 */ 282 struct r_debug r_debug; 283 284 #define GDB_STATE(s) do { \ 285 r_debug.r_state = s; r_debug_state(NULL, NULL); \ 286 } while (0) 287 288 /* 289 * Function for the debugger to set a breakpoint on to gain control. 290 */ 291 static void 292 r_debug_state(struct r_debug *dummy_one __unused, 293 struct link_map *dummy_two __unused) 294 { 295 } 296 297 static void 298 link_elf_add_gdb(struct link_map *l) 299 { 300 struct link_map *prev; 301 302 l->l_next = NULL; 303 304 if (r_debug.r_map == NULL) { 305 /* Add first. */ 306 l->l_prev = NULL; 307 r_debug.r_map = l; 308 } else { 309 /* Append to list. */ 310 for (prev = r_debug.r_map; 311 prev->l_next != NULL; 312 prev = prev->l_next) 313 ; 314 l->l_prev = prev; 315 prev->l_next = l; 316 } 317 } 318 319 static void 320 link_elf_delete_gdb(struct link_map *l) 321 { 322 if (l->l_prev == NULL) { 323 /* Remove first. */ 324 if ((r_debug.r_map = l->l_next) != NULL) 325 l->l_next->l_prev = NULL; 326 } else { 327 /* Remove any but first. */ 328 if ((l->l_prev->l_next = l->l_next) != NULL) 329 l->l_next->l_prev = l->l_prev; 330 } 331 } 332 #endif /* GDB */ 333 334 /* 335 * The kernel symbol table starts here. 336 */ 337 extern struct _dynamic _DYNAMIC; 338 339 static void 340 link_elf_error(const char *filename, const char *s) 341 { 342 if (filename == NULL) 343 printf("kldload: %s\n", s); 344 else 345 printf("kldload: %s: %s\n", filename, s); 346 } 347 348 static void 349 link_elf_invoke_ctors(caddr_t addr, size_t size) 350 { 351 void (**ctor)(void); 352 size_t i, cnt; 353 354 if (addr == NULL || size == 0) 355 return; 356 cnt = size / sizeof(*ctor); 357 ctor = (void *)addr; 358 for (i = 0; i < cnt; i++) { 359 if (ctor[i] != NULL) 360 (*ctor[i])(); 361 } 362 } 363 364 /* 365 * Actions performed after linking/loading both the preloaded kernel and any 366 * modules; whether preloaded or dynamicly loaded. 367 */ 368 static int 369 link_elf_link_common_finish(linker_file_t lf) 370 { 371 #ifdef GDB 372 elf_file_t ef = (elf_file_t)lf; 373 char *newfilename; 374 #endif 375 int error; 376 377 /* Notify MD code that a module is being loaded. */ 378 error = elf_cpu_load_file(lf); 379 if (error != 0) 380 return (error); 381 382 #ifdef GDB 383 GDB_STATE(RT_ADD); 384 ef->gdb.l_addr = lf->address; 385 newfilename = malloc(strlen(lf->filename) + 1, M_LINKER, M_WAITOK); 386 strcpy(newfilename, lf->filename); 387 ef->gdb.l_name = newfilename; 388 ef->gdb.l_ld = ef->dynamic; 389 link_elf_add_gdb(&ef->gdb); 390 GDB_STATE(RT_CONSISTENT); 391 #endif 392 393 /* Invoke .ctors */ 394 link_elf_invoke_ctors(lf->ctors_addr, lf->ctors_size); 395 return (0); 396 } 397 398 #ifdef RELOCATABLE_KERNEL 399 /* 400 * __startkernel and __endkernel are symbols set up as relocation canaries. 401 * 402 * They are defined in locore to reference linker script symbols at the 403 * beginning and end of the LOAD area. This has the desired side effect of 404 * giving us variables that have relative relocations pointing at them, so 405 * relocation of the kernel object will cause the variables to be updated 406 * automatically by the runtime linker when we initialize. 407 * 408 * There are two main reasons to relocate the kernel: 409 * 1) If the loader needed to load the kernel at an alternate load address. 410 * 2) If the kernel is switching address spaces on machines like POWER9 411 * under Radix where the high bits of the effective address are used to 412 * differentiate between hypervisor, host, guest, and problem state. 413 */ 414 extern vm_offset_t __startkernel, __endkernel; 415 #endif 416 417 static unsigned long kern_relbase = KERNBASE; 418 419 SYSCTL_ULONG(_kern, OID_AUTO, base_address, CTLFLAG_RD, 420 SYSCTL_NULL_ULONG_PTR, KERNBASE, "Kernel base address"); 421 SYSCTL_ULONG(_kern, OID_AUTO, relbase_address, CTLFLAG_RD, 422 &kern_relbase, 0, "Kernel relocated base address"); 423 424 static void 425 link_elf_init(void* arg) 426 { 427 Elf_Dyn *dp; 428 Elf_Addr *ctors_addrp; 429 Elf_Size *ctors_sizep; 430 caddr_t modptr, baseptr, sizeptr; 431 elf_file_t ef; 432 const char *modname; 433 434 linker_add_class(&link_elf_class); 435 436 dp = (Elf_Dyn *)&_DYNAMIC; 437 modname = NULL; 438 modptr = preload_search_by_type("elf" __XSTRING(__ELF_WORD_SIZE) " kernel"); 439 if (modptr == NULL) 440 modptr = preload_search_by_type("elf kernel"); 441 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 442 if (modname == NULL) 443 modname = "kernel"; 444 linker_kernel_file = linker_make_file(modname, &link_elf_class); 445 if (linker_kernel_file == NULL) 446 panic("%s: Can't create linker structures for kernel", 447 __func__); 448 449 ef = (elf_file_t) linker_kernel_file; 450 ef->preloaded = 1; 451 #ifdef RELOCATABLE_KERNEL 452 /* Compute relative displacement */ 453 ef->address = (caddr_t) (__startkernel - KERNBASE); 454 #else 455 ef->address = 0; 456 #endif 457 #ifdef SPARSE_MAPPING 458 ef->object = NULL; 459 #endif 460 ef->dynamic = dp; 461 462 if (dp != NULL) 463 parse_dynamic(ef); 464 #ifdef RELOCATABLE_KERNEL 465 linker_kernel_file->address = (caddr_t)__startkernel; 466 linker_kernel_file->size = (intptr_t)(__endkernel - __startkernel); 467 kern_relbase = (unsigned long)__startkernel; 468 #else 469 linker_kernel_file->address += KERNBASE; 470 linker_kernel_file->size = -(intptr_t)linker_kernel_file->address; 471 #endif 472 473 if (modptr != NULL) { 474 ef->modptr = modptr; 475 baseptr = preload_search_info(modptr, MODINFO_ADDR); 476 if (baseptr != NULL) 477 linker_kernel_file->address = *(caddr_t *)baseptr; 478 sizeptr = preload_search_info(modptr, MODINFO_SIZE); 479 if (sizeptr != NULL) 480 linker_kernel_file->size = *(size_t *)sizeptr; 481 ctors_addrp = (Elf_Addr *)preload_search_info(modptr, 482 MODINFO_METADATA | MODINFOMD_CTORS_ADDR); 483 ctors_sizep = (Elf_Size *)preload_search_info(modptr, 484 MODINFO_METADATA | MODINFOMD_CTORS_SIZE); 485 if (ctors_addrp != NULL && ctors_sizep != NULL) { 486 linker_kernel_file->ctors_addr = ef->address + 487 *ctors_addrp; 488 linker_kernel_file->ctors_size = *ctors_sizep; 489 } 490 } 491 (void)link_elf_preload_parse_symbols(ef); 492 493 #ifdef GDB 494 r_debug.r_map = NULL; 495 r_debug.r_brk = r_debug_state; 496 r_debug.r_state = RT_CONSISTENT; 497 #endif 498 499 (void)link_elf_link_common_finish(linker_kernel_file); 500 linker_kernel_file->flags |= LINKER_FILE_LINKED; 501 TAILQ_INIT(&set_pcpu_list); 502 #ifdef VIMAGE 503 TAILQ_INIT(&set_vnet_list); 504 #endif 505 } 506 507 SYSINIT(link_elf, SI_SUB_KLD, SI_ORDER_THIRD, link_elf_init, NULL); 508 509 static int 510 link_elf_preload_parse_symbols(elf_file_t ef) 511 { 512 caddr_t pointer; 513 caddr_t ssym, esym, base; 514 caddr_t strtab; 515 int strcnt; 516 Elf_Sym *symtab; 517 int symcnt; 518 519 if (ef->modptr == NULL) 520 return (0); 521 pointer = preload_search_info(ef->modptr, 522 MODINFO_METADATA | MODINFOMD_SSYM); 523 if (pointer == NULL) 524 return (0); 525 ssym = *(caddr_t *)pointer; 526 pointer = preload_search_info(ef->modptr, 527 MODINFO_METADATA | MODINFOMD_ESYM); 528 if (pointer == NULL) 529 return (0); 530 esym = *(caddr_t *)pointer; 531 532 base = ssym; 533 534 symcnt = *(long *)base; 535 base += sizeof(long); 536 symtab = (Elf_Sym *)base; 537 base += roundup(symcnt, sizeof(long)); 538 539 if (base > esym || base < ssym) { 540 printf("Symbols are corrupt!\n"); 541 return (EINVAL); 542 } 543 544 strcnt = *(long *)base; 545 base += sizeof(long); 546 strtab = base; 547 base += roundup(strcnt, sizeof(long)); 548 549 if (base > esym || base < ssym) { 550 printf("Symbols are corrupt!\n"); 551 return (EINVAL); 552 } 553 554 ef->ddbsymtab = symtab; 555 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym); 556 ef->ddbstrtab = strtab; 557 ef->ddbstrcnt = strcnt; 558 559 return (0); 560 } 561 562 static int 563 parse_dynamic(elf_file_t ef) 564 { 565 Elf_Dyn *dp; 566 int plttype = DT_REL; 567 568 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) { 569 switch (dp->d_tag) { 570 case DT_HASH: 571 { 572 /* From src/libexec/rtld-elf/rtld.c */ 573 const Elf_Hashelt *hashtab = (const Elf_Hashelt *) 574 (ef->address + dp->d_un.d_ptr); 575 ef->nbuckets = hashtab[0]; 576 ef->nchains = hashtab[1]; 577 ef->buckets = hashtab + 2; 578 ef->chains = ef->buckets + ef->nbuckets; 579 break; 580 } 581 case DT_STRTAB: 582 ef->strtab = (caddr_t) (ef->address + dp->d_un.d_ptr); 583 break; 584 case DT_STRSZ: 585 ef->strsz = dp->d_un.d_val; 586 break; 587 case DT_SYMTAB: 588 ef->symtab = (Elf_Sym*) (ef->address + dp->d_un.d_ptr); 589 break; 590 case DT_SYMENT: 591 if (dp->d_un.d_val != sizeof(Elf_Sym)) 592 return (ENOEXEC); 593 break; 594 case DT_PLTGOT: 595 ef->got = (Elf_Addr *) (ef->address + dp->d_un.d_ptr); 596 break; 597 case DT_REL: 598 ef->rel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr); 599 break; 600 case DT_RELSZ: 601 ef->relsize = dp->d_un.d_val; 602 break; 603 case DT_RELENT: 604 if (dp->d_un.d_val != sizeof(Elf_Rel)) 605 return (ENOEXEC); 606 break; 607 case DT_JMPREL: 608 ef->pltrel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr); 609 break; 610 case DT_PLTRELSZ: 611 ef->pltrelsize = dp->d_un.d_val; 612 break; 613 case DT_RELA: 614 ef->rela = (const Elf_Rela *) (ef->address + dp->d_un.d_ptr); 615 break; 616 case DT_RELASZ: 617 ef->relasize = dp->d_un.d_val; 618 break; 619 case DT_RELAENT: 620 if (dp->d_un.d_val != sizeof(Elf_Rela)) 621 return (ENOEXEC); 622 break; 623 case DT_PLTREL: 624 plttype = dp->d_un.d_val; 625 if (plttype != DT_REL && plttype != DT_RELA) 626 return (ENOEXEC); 627 break; 628 #ifdef GDB 629 case DT_DEBUG: 630 dp->d_un.d_ptr = (Elf_Addr)&r_debug; 631 break; 632 #endif 633 } 634 } 635 636 if (plttype == DT_RELA) { 637 ef->pltrela = (const Elf_Rela *)ef->pltrel; 638 ef->pltrel = NULL; 639 ef->pltrelasize = ef->pltrelsize; 640 ef->pltrelsize = 0; 641 } 642 643 ef->ddbsymtab = ef->symtab; 644 ef->ddbsymcnt = ef->nchains; 645 ef->ddbstrtab = ef->strtab; 646 ef->ddbstrcnt = ef->strsz; 647 648 return elf_cpu_parse_dynamic(ef->address, ef->dynamic); 649 } 650 651 #define LS_PADDING 0x90909090 652 static int 653 parse_dpcpu(elf_file_t ef) 654 { 655 int error, size; 656 #if defined(__i386__) 657 uint32_t pad; 658 #endif 659 660 ef->pcpu_start = 0; 661 ef->pcpu_stop = 0; 662 error = link_elf_lookup_set(&ef->lf, "pcpu", (void ***)&ef->pcpu_start, 663 (void ***)&ef->pcpu_stop, NULL); 664 /* Error just means there is no pcpu set to relocate. */ 665 if (error != 0) 666 return (0); 667 size = (uintptr_t)ef->pcpu_stop - (uintptr_t)ef->pcpu_start; 668 /* Empty set? */ 669 if (size < 1) 670 return (0); 671 #if defined(__i386__) 672 /* In case we do find __start/stop_set_ symbols double-check. */ 673 if (size < 4) { 674 uprintf("Kernel module '%s' must be recompiled with " 675 "linker script\n", ef->lf.pathname); 676 return (ENOEXEC); 677 } 678 679 /* Padding from linker-script correct? */ 680 pad = *(uint32_t *)((uintptr_t)ef->pcpu_stop - sizeof(pad)); 681 if (pad != LS_PADDING) { 682 uprintf("Kernel module '%s' must be recompiled with " 683 "linker script, invalid padding %#04x (%#04x)\n", 684 ef->lf.pathname, pad, LS_PADDING); 685 return (ENOEXEC); 686 } 687 /* If we only have valid padding, nothing to do. */ 688 if (size == 4) 689 return (0); 690 #endif 691 /* 692 * Allocate space in the primary pcpu area. Copy in our 693 * initialization from the data section and then initialize 694 * all per-cpu storage from that. 695 */ 696 ef->pcpu_base = (Elf_Addr)(uintptr_t)dpcpu_alloc(size); 697 if (ef->pcpu_base == 0) { 698 printf("%s: pcpu module space is out of space; " 699 "cannot allocate %d for %s\n", 700 __func__, size, ef->lf.pathname); 701 return (ENOSPC); 702 } 703 memcpy((void *)ef->pcpu_base, (void *)ef->pcpu_start, size); 704 dpcpu_copy((void *)ef->pcpu_base, size); 705 elf_set_add(&set_pcpu_list, ef->pcpu_start, ef->pcpu_stop, 706 ef->pcpu_base); 707 708 return (0); 709 } 710 711 #ifdef VIMAGE 712 static int 713 parse_vnet(elf_file_t ef) 714 { 715 int error, size; 716 #if defined(__i386__) 717 uint32_t pad; 718 #endif 719 720 ef->vnet_start = 0; 721 ef->vnet_stop = 0; 722 error = link_elf_lookup_set(&ef->lf, "vnet", (void ***)&ef->vnet_start, 723 (void ***)&ef->vnet_stop, NULL); 724 /* Error just means there is no vnet data set to relocate. */ 725 if (error != 0) 726 return (0); 727 size = (uintptr_t)ef->vnet_stop - (uintptr_t)ef->vnet_start; 728 /* Empty set? */ 729 if (size < 1) 730 return (0); 731 #if defined(__i386__) 732 /* In case we do find __start/stop_set_ symbols double-check. */ 733 if (size < 4) { 734 uprintf("Kernel module '%s' must be recompiled with " 735 "linker script\n", ef->lf.pathname); 736 return (ENOEXEC); 737 } 738 739 /* Padding from linker-script correct? */ 740 pad = *(uint32_t *)((uintptr_t)ef->vnet_stop - sizeof(pad)); 741 if (pad != LS_PADDING) { 742 uprintf("Kernel module '%s' must be recompiled with " 743 "linker script, invalid padding %#04x (%#04x)\n", 744 ef->lf.pathname, pad, LS_PADDING); 745 return (ENOEXEC); 746 } 747 /* If we only have valid padding, nothing to do. */ 748 if (size == 4) 749 return (0); 750 #endif 751 /* 752 * Allocate space in the primary vnet area. Copy in our 753 * initialization from the data section and then initialize 754 * all per-vnet storage from that. 755 */ 756 ef->vnet_base = (Elf_Addr)(uintptr_t)vnet_data_alloc(size); 757 if (ef->vnet_base == 0) { 758 printf("%s: vnet module space is out of space; " 759 "cannot allocate %d for %s\n", 760 __func__, size, ef->lf.pathname); 761 return (ENOSPC); 762 } 763 memcpy((void *)ef->vnet_base, (void *)ef->vnet_start, size); 764 vnet_data_copy((void *)ef->vnet_base, size); 765 elf_set_add(&set_vnet_list, ef->vnet_start, ef->vnet_stop, 766 ef->vnet_base); 767 768 return (0); 769 } 770 #endif 771 #undef LS_PADDING 772 773 /* 774 * Apply the specified protection to the loadable segments of a preloaded linker 775 * file. 776 */ 777 static int 778 preload_protect(elf_file_t ef, vm_prot_t prot) 779 { 780 #if defined(__aarch64__) || defined(__amd64__) 781 Elf_Ehdr *hdr; 782 Elf_Phdr *phdr, *phlimit; 783 vm_prot_t nprot; 784 int error; 785 786 error = 0; 787 hdr = (Elf_Ehdr *)ef->address; 788 phdr = (Elf_Phdr *)(ef->address + hdr->e_phoff); 789 phlimit = phdr + hdr->e_phnum; 790 for (; phdr < phlimit; phdr++) { 791 if (phdr->p_type != PT_LOAD) 792 continue; 793 794 nprot = prot | VM_PROT_READ; 795 if ((phdr->p_flags & PF_W) != 0) 796 nprot |= VM_PROT_WRITE; 797 if ((phdr->p_flags & PF_X) != 0) 798 nprot |= VM_PROT_EXECUTE; 799 error = pmap_change_prot((vm_offset_t)ef->address + 800 phdr->p_vaddr, round_page(phdr->p_memsz), nprot); 801 if (error != 0) 802 break; 803 } 804 return (error); 805 #else 806 return (0); 807 #endif 808 } 809 810 #ifdef __arm__ 811 /* 812 * Locate the ARM exception/unwind table info for DDB and stack(9) use by 813 * searching for the section header that describes it. There may be no unwind 814 * info, for example in a module containing only data. 815 */ 816 static void 817 link_elf_locate_exidx(linker_file_t lf, Elf_Shdr *shdr, int nhdr) 818 { 819 int i; 820 821 for (i = 0; i < nhdr; i++) { 822 if (shdr[i].sh_type == SHT_ARM_EXIDX) { 823 lf->exidx_addr = shdr[i].sh_addr + lf->address; 824 lf->exidx_size = shdr[i].sh_size; 825 break; 826 } 827 } 828 } 829 830 /* 831 * Locate the section headers metadata in a preloaded module, then use it to 832 * locate the exception/unwind table in the module. The size of the metadata 833 * block is stored in a uint32 word immediately before the data itself, and a 834 * comment in preload_search_info() says it is safe to rely on that. 835 */ 836 static void 837 link_elf_locate_exidx_preload(struct linker_file *lf, caddr_t modptr) 838 { 839 uint32_t *modinfo; 840 Elf_Shdr *shdr; 841 uint32_t nhdr; 842 843 modinfo = (uint32_t *)preload_search_info(modptr, 844 MODINFO_METADATA | MODINFOMD_SHDR); 845 if (modinfo != NULL) { 846 shdr = (Elf_Shdr *)modinfo; 847 nhdr = modinfo[-1] / sizeof(Elf_Shdr); 848 link_elf_locate_exidx(lf, shdr, nhdr); 849 } 850 } 851 852 #endif /* __arm__ */ 853 854 static int 855 link_elf_link_preload(linker_class_t cls, const char *filename, 856 linker_file_t *result) 857 { 858 Elf_Addr *ctors_addrp; 859 Elf_Size *ctors_sizep; 860 caddr_t modptr, baseptr, sizeptr, dynptr; 861 char *type; 862 elf_file_t ef; 863 linker_file_t lf; 864 int error; 865 vm_offset_t dp; 866 867 /* Look to see if we have the file preloaded */ 868 modptr = preload_search_by_name(filename); 869 if (modptr == NULL) 870 return (ENOENT); 871 872 type = (char *)preload_search_info(modptr, MODINFO_TYPE); 873 baseptr = preload_search_info(modptr, MODINFO_ADDR); 874 sizeptr = preload_search_info(modptr, MODINFO_SIZE); 875 dynptr = preload_search_info(modptr, 876 MODINFO_METADATA | MODINFOMD_DYNAMIC); 877 if (type == NULL || 878 (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) " module") != 0 && 879 strcmp(type, "elf module") != 0)) 880 return (EFTYPE); 881 if (baseptr == NULL || sizeptr == NULL || dynptr == NULL) 882 return (EINVAL); 883 884 lf = linker_make_file(filename, &link_elf_class); 885 if (lf == NULL) 886 return (ENOMEM); 887 888 ef = (elf_file_t) lf; 889 ef->preloaded = 1; 890 ef->modptr = modptr; 891 ef->address = *(caddr_t *)baseptr; 892 #ifdef SPARSE_MAPPING 893 ef->object = NULL; 894 #endif 895 dp = (vm_offset_t)ef->address + *(vm_offset_t *)dynptr; 896 ef->dynamic = (Elf_Dyn *)dp; 897 lf->address = ef->address; 898 lf->size = *(size_t *)sizeptr; 899 900 ctors_addrp = (Elf_Addr *)preload_search_info(modptr, 901 MODINFO_METADATA | MODINFOMD_CTORS_ADDR); 902 ctors_sizep = (Elf_Size *)preload_search_info(modptr, 903 MODINFO_METADATA | MODINFOMD_CTORS_SIZE); 904 if (ctors_addrp != NULL && ctors_sizep != NULL) { 905 lf->ctors_addr = ef->address + *ctors_addrp; 906 lf->ctors_size = *ctors_sizep; 907 } 908 909 #ifdef __arm__ 910 link_elf_locate_exidx_preload(lf, modptr); 911 #endif 912 913 error = parse_dynamic(ef); 914 if (error == 0) 915 error = parse_dpcpu(ef); 916 #ifdef VIMAGE 917 if (error == 0) 918 error = parse_vnet(ef); 919 #endif 920 if (error == 0) 921 error = preload_protect(ef, VM_PROT_ALL); 922 if (error != 0) { 923 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 924 return (error); 925 } 926 link_elf_reloc_local(lf); 927 *result = lf; 928 return (0); 929 } 930 931 static int 932 link_elf_link_preload_finish(linker_file_t lf) 933 { 934 elf_file_t ef; 935 int error; 936 937 ef = (elf_file_t) lf; 938 error = relocate_file(ef); 939 if (error == 0) 940 error = preload_protect(ef, VM_PROT_NONE); 941 if (error != 0) 942 return (error); 943 (void)link_elf_preload_parse_symbols(ef); 944 945 return (link_elf_link_common_finish(lf)); 946 } 947 948 static int 949 link_elf_load_file(linker_class_t cls, const char* filename, 950 linker_file_t* result) 951 { 952 struct nameidata nd; 953 struct thread* td = curthread; /* XXX */ 954 Elf_Ehdr *hdr; 955 caddr_t firstpage, segbase; 956 int nbytes, i; 957 Elf_Phdr *phdr; 958 Elf_Phdr *phlimit; 959 Elf_Phdr *segs[MAXSEGS]; 960 int nsegs; 961 Elf_Phdr *phdyn; 962 caddr_t mapbase; 963 size_t mapsize; 964 Elf_Addr base_vaddr; 965 Elf_Addr base_vlimit; 966 int error = 0; 967 ssize_t resid; 968 int flags; 969 elf_file_t ef; 970 linker_file_t lf; 971 Elf_Shdr *shdr; 972 int symtabindex; 973 int symstrindex; 974 int shstrindex; 975 int symcnt; 976 int strcnt; 977 char *shstrs; 978 979 shdr = NULL; 980 lf = NULL; 981 shstrs = NULL; 982 983 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename); 984 flags = FREAD; 985 error = vn_open(&nd, &flags, 0, NULL); 986 if (error != 0) 987 return (error); 988 NDFREE_PNBUF(&nd); 989 if (nd.ni_vp->v_type != VREG) { 990 error = ENOEXEC; 991 firstpage = NULL; 992 goto out; 993 } 994 #ifdef MAC 995 error = mac_kld_check_load(curthread->td_ucred, nd.ni_vp); 996 if (error != 0) { 997 firstpage = NULL; 998 goto out; 999 } 1000 #endif 1001 1002 /* 1003 * Read the elf header from the file. 1004 */ 1005 firstpage = malloc(PAGE_SIZE, M_LINKER, M_WAITOK); 1006 hdr = (Elf_Ehdr *)firstpage; 1007 error = vn_rdwr(UIO_READ, nd.ni_vp, firstpage, PAGE_SIZE, 0, 1008 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1009 &resid, td); 1010 nbytes = PAGE_SIZE - resid; 1011 if (error != 0) 1012 goto out; 1013 1014 if (!IS_ELF(*hdr)) { 1015 error = ENOEXEC; 1016 goto out; 1017 } 1018 1019 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 1020 hdr->e_ident[EI_DATA] != ELF_TARG_DATA) { 1021 link_elf_error(filename, "Unsupported file layout"); 1022 error = ENOEXEC; 1023 goto out; 1024 } 1025 if (hdr->e_ident[EI_VERSION] != EV_CURRENT || 1026 hdr->e_version != EV_CURRENT) { 1027 link_elf_error(filename, "Unsupported file version"); 1028 error = ENOEXEC; 1029 goto out; 1030 } 1031 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) { 1032 error = ENOSYS; 1033 goto out; 1034 } 1035 if (hdr->e_machine != ELF_TARG_MACH) { 1036 link_elf_error(filename, "Unsupported machine"); 1037 error = ENOEXEC; 1038 goto out; 1039 } 1040 1041 /* 1042 * We rely on the program header being in the first page. 1043 * This is not strictly required by the ABI specification, but 1044 * it seems to always true in practice. And, it simplifies 1045 * things considerably. 1046 */ 1047 if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) && 1048 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) && 1049 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes))) 1050 link_elf_error(filename, "Unreadable program headers"); 1051 1052 /* 1053 * Scan the program header entries, and save key information. 1054 * 1055 * We rely on there being exactly two load segments, text and data, 1056 * in that order. 1057 */ 1058 phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff); 1059 phlimit = phdr + hdr->e_phnum; 1060 nsegs = 0; 1061 phdyn = NULL; 1062 while (phdr < phlimit) { 1063 switch (phdr->p_type) { 1064 case PT_LOAD: 1065 if (nsegs == MAXSEGS) { 1066 link_elf_error(filename, "Too many sections"); 1067 error = ENOEXEC; 1068 goto out; 1069 } 1070 /* 1071 * XXX: We just trust they come in right order ?? 1072 */ 1073 segs[nsegs] = phdr; 1074 ++nsegs; 1075 break; 1076 1077 case PT_DYNAMIC: 1078 phdyn = phdr; 1079 break; 1080 1081 case PT_INTERP: 1082 error = ENOSYS; 1083 goto out; 1084 } 1085 1086 ++phdr; 1087 } 1088 if (phdyn == NULL) { 1089 link_elf_error(filename, "Object is not dynamically-linked"); 1090 error = ENOEXEC; 1091 goto out; 1092 } 1093 if (nsegs == 0) { 1094 link_elf_error(filename, "No sections"); 1095 error = ENOEXEC; 1096 goto out; 1097 } 1098 1099 /* 1100 * Allocate the entire address space of the object, to stake 1101 * out our contiguous region, and to establish the base 1102 * address for relocation. 1103 */ 1104 base_vaddr = trunc_page(segs[0]->p_vaddr); 1105 base_vlimit = round_page(segs[nsegs - 1]->p_vaddr + 1106 segs[nsegs - 1]->p_memsz); 1107 mapsize = base_vlimit - base_vaddr; 1108 1109 lf = linker_make_file(filename, &link_elf_class); 1110 if (lf == NULL) { 1111 error = ENOMEM; 1112 goto out; 1113 } 1114 1115 ef = (elf_file_t) lf; 1116 #ifdef SPARSE_MAPPING 1117 ef->object = vm_pager_allocate(OBJT_PHYS, NULL, mapsize, VM_PROT_ALL, 1118 0, thread0.td_ucred); 1119 if (ef->object == NULL) { 1120 error = ENOMEM; 1121 goto out; 1122 } 1123 #ifdef __amd64__ 1124 mapbase = (caddr_t)KERNBASE; 1125 #else 1126 mapbase = (caddr_t)vm_map_min(kernel_map); 1127 #endif 1128 /* 1129 * Mapping protections are downgraded after relocation processing. 1130 */ 1131 error = vm_map_find(kernel_map, ef->object, 0, 1132 (vm_offset_t *)&mapbase, mapsize, 0, VMFS_OPTIMAL_SPACE, 1133 VM_PROT_ALL, VM_PROT_ALL, 0); 1134 if (error != 0) { 1135 vm_object_deallocate(ef->object); 1136 ef->object = NULL; 1137 goto out; 1138 } 1139 #else 1140 mapbase = malloc_exec(mapsize, M_LINKER, M_WAITOK); 1141 #endif 1142 ef->address = mapbase; 1143 1144 /* 1145 * Read the text and data sections and zero the bss. 1146 */ 1147 for (i = 0; i < nsegs; i++) { 1148 segbase = mapbase + segs[i]->p_vaddr - base_vaddr; 1149 1150 #ifdef SPARSE_MAPPING 1151 /* 1152 * Consecutive segments may have different mapping permissions, 1153 * so be strict and verify that their mappings do not overlap. 1154 */ 1155 if (((vm_offset_t)segbase & PAGE_MASK) != 0) { 1156 error = EINVAL; 1157 goto out; 1158 } 1159 1160 error = vm_map_wire(kernel_map, 1161 (vm_offset_t)segbase, 1162 (vm_offset_t)segbase + round_page(segs[i]->p_memsz), 1163 VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES); 1164 if (error != KERN_SUCCESS) { 1165 error = ENOMEM; 1166 goto out; 1167 } 1168 #endif 1169 1170 error = vn_rdwr(UIO_READ, nd.ni_vp, 1171 segbase, segs[i]->p_filesz, segs[i]->p_offset, 1172 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1173 &resid, td); 1174 if (error != 0) 1175 goto out; 1176 bzero(segbase + segs[i]->p_filesz, 1177 segs[i]->p_memsz - segs[i]->p_filesz); 1178 } 1179 1180 ef->dynamic = (Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr); 1181 1182 lf->address = ef->address; 1183 lf->size = mapsize; 1184 1185 error = parse_dynamic(ef); 1186 if (error != 0) 1187 goto out; 1188 error = parse_dpcpu(ef); 1189 if (error != 0) 1190 goto out; 1191 #ifdef VIMAGE 1192 error = parse_vnet(ef); 1193 if (error != 0) 1194 goto out; 1195 #endif 1196 link_elf_reloc_local(lf); 1197 1198 VOP_UNLOCK(nd.ni_vp); 1199 error = linker_load_dependencies(lf); 1200 vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY); 1201 if (error != 0) 1202 goto out; 1203 error = relocate_file(ef); 1204 if (error != 0) 1205 goto out; 1206 1207 #ifdef SPARSE_MAPPING 1208 /* 1209 * Downgrade permissions on text segment mappings now that relocation 1210 * processing is complete. Restrict permissions on read-only segments. 1211 */ 1212 for (i = 0; i < nsegs; i++) { 1213 vm_prot_t prot; 1214 1215 if (segs[i]->p_type != PT_LOAD) 1216 continue; 1217 1218 prot = VM_PROT_READ; 1219 if ((segs[i]->p_flags & PF_W) != 0) 1220 prot |= VM_PROT_WRITE; 1221 if ((segs[i]->p_flags & PF_X) != 0) 1222 prot |= VM_PROT_EXECUTE; 1223 segbase = mapbase + segs[i]->p_vaddr - base_vaddr; 1224 error = vm_map_protect(kernel_map, 1225 (vm_offset_t)segbase, 1226 (vm_offset_t)segbase + round_page(segs[i]->p_memsz), 1227 prot, 0, VM_MAP_PROTECT_SET_PROT); 1228 if (error != KERN_SUCCESS) { 1229 error = ENOMEM; 1230 goto out; 1231 } 1232 } 1233 #endif 1234 1235 /* 1236 * Try and load the symbol table if it's present. (you can 1237 * strip it!) 1238 */ 1239 nbytes = hdr->e_shnum * hdr->e_shentsize; 1240 if (nbytes == 0 || hdr->e_shoff == 0) 1241 goto nosyms; 1242 shdr = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO); 1243 error = vn_rdwr(UIO_READ, nd.ni_vp, 1244 (caddr_t)shdr, nbytes, hdr->e_shoff, 1245 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1246 &resid, td); 1247 if (error != 0) 1248 goto out; 1249 1250 /* Read section string table */ 1251 shstrindex = hdr->e_shstrndx; 1252 if (shstrindex != 0 && shdr[shstrindex].sh_type == SHT_STRTAB && 1253 shdr[shstrindex].sh_size != 0) { 1254 nbytes = shdr[shstrindex].sh_size; 1255 shstrs = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO); 1256 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shstrs, nbytes, 1257 shdr[shstrindex].sh_offset, UIO_SYSSPACE, IO_NODELOCKED, 1258 td->td_ucred, NOCRED, &resid, td); 1259 if (error) 1260 goto out; 1261 } 1262 1263 symtabindex = -1; 1264 symstrindex = -1; 1265 for (i = 0; i < hdr->e_shnum; i++) { 1266 if (shdr[i].sh_type == SHT_SYMTAB) { 1267 symtabindex = i; 1268 symstrindex = shdr[i].sh_link; 1269 } else if (shstrs != NULL && shdr[i].sh_name != 0 && 1270 strcmp(shstrs + shdr[i].sh_name, ".ctors") == 0) { 1271 /* Record relocated address and size of .ctors. */ 1272 lf->ctors_addr = mapbase + shdr[i].sh_addr - base_vaddr; 1273 lf->ctors_size = shdr[i].sh_size; 1274 } 1275 } 1276 if (symtabindex < 0 || symstrindex < 0) 1277 goto nosyms; 1278 1279 symcnt = shdr[symtabindex].sh_size; 1280 ef->symbase = malloc(symcnt, M_LINKER, M_WAITOK); 1281 strcnt = shdr[symstrindex].sh_size; 1282 ef->strbase = malloc(strcnt, M_LINKER, M_WAITOK); 1283 1284 error = vn_rdwr(UIO_READ, nd.ni_vp, 1285 ef->symbase, symcnt, shdr[symtabindex].sh_offset, 1286 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1287 &resid, td); 1288 if (error != 0) 1289 goto out; 1290 error = vn_rdwr(UIO_READ, nd.ni_vp, 1291 ef->strbase, strcnt, shdr[symstrindex].sh_offset, 1292 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1293 &resid, td); 1294 if (error != 0) 1295 goto out; 1296 1297 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym); 1298 ef->ddbsymtab = (const Elf_Sym *)ef->symbase; 1299 ef->ddbstrcnt = strcnt; 1300 ef->ddbstrtab = ef->strbase; 1301 1302 nosyms: 1303 1304 #ifdef __arm__ 1305 link_elf_locate_exidx(lf, shdr, hdr->e_shnum); 1306 #endif 1307 1308 error = link_elf_link_common_finish(lf); 1309 if (error != 0) 1310 goto out; 1311 1312 *result = lf; 1313 1314 out: 1315 VOP_UNLOCK(nd.ni_vp); 1316 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1317 if (error != 0 && lf != NULL) 1318 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1319 free(shdr, M_LINKER); 1320 free(firstpage, M_LINKER); 1321 free(shstrs, M_LINKER); 1322 1323 return (error); 1324 } 1325 1326 Elf_Addr 1327 elf_relocaddr(linker_file_t lf, Elf_Addr x) 1328 { 1329 elf_file_t ef; 1330 1331 KASSERT(lf->ops->cls == (kobj_class_t)&link_elf_class, 1332 ("elf_relocaddr: unexpected linker file %p", lf)); 1333 1334 ef = (elf_file_t)lf; 1335 if (x >= ef->pcpu_start && x < ef->pcpu_stop) 1336 return ((x - ef->pcpu_start) + ef->pcpu_base); 1337 #ifdef VIMAGE 1338 if (x >= ef->vnet_start && x < ef->vnet_stop) 1339 return ((x - ef->vnet_start) + ef->vnet_base); 1340 #endif 1341 return (x); 1342 } 1343 1344 static void 1345 link_elf_unload_file(linker_file_t file) 1346 { 1347 elf_file_t ef = (elf_file_t) file; 1348 1349 if (ef->pcpu_base != 0) { 1350 dpcpu_free((void *)ef->pcpu_base, 1351 ef->pcpu_stop - ef->pcpu_start); 1352 elf_set_delete(&set_pcpu_list, ef->pcpu_start); 1353 } 1354 #ifdef VIMAGE 1355 if (ef->vnet_base != 0) { 1356 vnet_data_free((void *)ef->vnet_base, 1357 ef->vnet_stop - ef->vnet_start); 1358 elf_set_delete(&set_vnet_list, ef->vnet_start); 1359 } 1360 #endif 1361 #ifdef GDB 1362 if (ef->gdb.l_ld != NULL) { 1363 GDB_STATE(RT_DELETE); 1364 free((void *)(uintptr_t)ef->gdb.l_name, M_LINKER); 1365 link_elf_delete_gdb(&ef->gdb); 1366 GDB_STATE(RT_CONSISTENT); 1367 } 1368 #endif 1369 1370 /* Notify MD code that a module is being unloaded. */ 1371 elf_cpu_unload_file(file); 1372 1373 if (ef->preloaded) { 1374 link_elf_unload_preload(file); 1375 return; 1376 } 1377 1378 #ifdef SPARSE_MAPPING 1379 if (ef->object != NULL) { 1380 vm_map_remove(kernel_map, (vm_offset_t) ef->address, 1381 (vm_offset_t) ef->address 1382 + (ef->object->size << PAGE_SHIFT)); 1383 } 1384 #else 1385 free(ef->address, M_LINKER); 1386 #endif 1387 free(ef->symbase, M_LINKER); 1388 free(ef->strbase, M_LINKER); 1389 free(ef->ctftab, M_LINKER); 1390 free(ef->ctfoff, M_LINKER); 1391 free(ef->typoff, M_LINKER); 1392 } 1393 1394 static void 1395 link_elf_unload_preload(linker_file_t file) 1396 { 1397 1398 if (file->pathname != NULL) 1399 preload_delete_name(file->pathname); 1400 } 1401 1402 static const char * 1403 symbol_name(elf_file_t ef, Elf_Size r_info) 1404 { 1405 const Elf_Sym *ref; 1406 1407 if (ELF_R_SYM(r_info)) { 1408 ref = ef->symtab + ELF_R_SYM(r_info); 1409 return (ef->strtab + ref->st_name); 1410 } 1411 return (NULL); 1412 } 1413 1414 static int 1415 symbol_type(elf_file_t ef, Elf_Size r_info) 1416 { 1417 const Elf_Sym *ref; 1418 1419 if (ELF_R_SYM(r_info)) { 1420 ref = ef->symtab + ELF_R_SYM(r_info); 1421 return (ELF_ST_TYPE(ref->st_info)); 1422 } 1423 return (STT_NOTYPE); 1424 } 1425 1426 static int 1427 relocate_file1(elf_file_t ef, elf_lookup_fn lookup, elf_reloc_fn reloc, 1428 bool ifuncs) 1429 { 1430 const Elf_Rel *rel; 1431 const Elf_Rela *rela; 1432 const char *symname; 1433 1434 #define APPLY_RELOCS(iter, tbl, tblsize, type) do { \ 1435 for ((iter) = (tbl); (iter) != NULL && \ 1436 (iter) < (tbl) + (tblsize) / sizeof(*(iter)); (iter)++) { \ 1437 if ((symbol_type(ef, (iter)->r_info) == \ 1438 STT_GNU_IFUNC || \ 1439 elf_is_ifunc_reloc((iter)->r_info)) != ifuncs) \ 1440 continue; \ 1441 if (reloc(&ef->lf, (Elf_Addr)ef->address, \ 1442 (iter), (type), lookup)) { \ 1443 symname = symbol_name(ef, (iter)->r_info); \ 1444 printf("link_elf: symbol %s undefined\n", \ 1445 symname); \ 1446 return (ENOENT); \ 1447 } \ 1448 } \ 1449 } while (0) 1450 1451 APPLY_RELOCS(rel, ef->rel, ef->relsize, ELF_RELOC_REL); 1452 APPLY_RELOCS(rela, ef->rela, ef->relasize, ELF_RELOC_RELA); 1453 APPLY_RELOCS(rel, ef->pltrel, ef->pltrelsize, ELF_RELOC_REL); 1454 APPLY_RELOCS(rela, ef->pltrela, ef->pltrelasize, ELF_RELOC_RELA); 1455 1456 #undef APPLY_RELOCS 1457 1458 return (0); 1459 } 1460 1461 static int 1462 relocate_file(elf_file_t ef) 1463 { 1464 int error; 1465 1466 error = relocate_file1(ef, elf_lookup, elf_reloc, false); 1467 if (error == 0) 1468 error = relocate_file1(ef, elf_lookup, elf_reloc, true); 1469 return (error); 1470 } 1471 1472 /* 1473 * Hash function for symbol table lookup. Don't even think about changing 1474 * this. It is specified by the System V ABI. 1475 */ 1476 static unsigned long 1477 elf_hash(const char *name) 1478 { 1479 const unsigned char *p = (const unsigned char *) name; 1480 unsigned long h = 0; 1481 unsigned long g; 1482 1483 while (*p != '\0') { 1484 h = (h << 4) + *p++; 1485 if ((g = h & 0xf0000000) != 0) 1486 h ^= g >> 24; 1487 h &= ~g; 1488 } 1489 return (h); 1490 } 1491 1492 static int 1493 link_elf_lookup_symbol1(linker_file_t lf, const char *name, c_linker_sym_t *sym, 1494 bool see_local) 1495 { 1496 elf_file_t ef = (elf_file_t) lf; 1497 unsigned long symnum; 1498 const Elf_Sym* symp; 1499 const char *strp; 1500 unsigned long hash; 1501 1502 /* If we don't have a hash, bail. */ 1503 if (ef->buckets == NULL || ef->nbuckets == 0) { 1504 printf("link_elf_lookup_symbol: missing symbol hash table\n"); 1505 return (ENOENT); 1506 } 1507 1508 /* First, search hashed global symbols */ 1509 hash = elf_hash(name); 1510 symnum = ef->buckets[hash % ef->nbuckets]; 1511 1512 while (symnum != STN_UNDEF) { 1513 if (symnum >= ef->nchains) { 1514 printf("%s: corrupt symbol table\n", __func__); 1515 return (ENOENT); 1516 } 1517 1518 symp = ef->symtab + symnum; 1519 if (symp->st_name == 0) { 1520 printf("%s: corrupt symbol table\n", __func__); 1521 return (ENOENT); 1522 } 1523 1524 strp = ef->strtab + symp->st_name; 1525 1526 if (strcmp(name, strp) == 0) { 1527 if (symp->st_shndx != SHN_UNDEF || 1528 (symp->st_value != 0 && 1529 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1530 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC))) { 1531 if (see_local || 1532 ELF_ST_BIND(symp->st_info) != STB_LOCAL) { 1533 *sym = (c_linker_sym_t) symp; 1534 return (0); 1535 } 1536 } 1537 return (ENOENT); 1538 } 1539 1540 symnum = ef->chains[symnum]; 1541 } 1542 1543 return (ENOENT); 1544 } 1545 1546 static int 1547 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym) 1548 { 1549 if (link_elf_leak_locals) 1550 return (link_elf_lookup_debug_symbol(lf, name, sym)); 1551 return (link_elf_lookup_symbol1(lf, name, sym, false)); 1552 } 1553 1554 static int 1555 link_elf_lookup_debug_symbol(linker_file_t lf, const char *name, 1556 c_linker_sym_t *sym) 1557 { 1558 elf_file_t ef = (elf_file_t)lf; 1559 const Elf_Sym* symp; 1560 const char *strp; 1561 int i; 1562 1563 if (link_elf_lookup_symbol1(lf, name, sym, true) == 0) 1564 return (0); 1565 1566 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1567 strp = ef->ddbstrtab + symp->st_name; 1568 if (strcmp(name, strp) == 0) { 1569 if (symp->st_shndx != SHN_UNDEF || 1570 (symp->st_value != 0 && 1571 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1572 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC))) { 1573 *sym = (c_linker_sym_t) symp; 1574 return (0); 1575 } 1576 return (ENOENT); 1577 } 1578 } 1579 1580 return (ENOENT); 1581 } 1582 1583 static int 1584 link_elf_symbol_values1(linker_file_t lf, c_linker_sym_t sym, 1585 linker_symval_t *symval, bool see_local) 1586 { 1587 elf_file_t ef; 1588 const Elf_Sym *es; 1589 caddr_t val; 1590 1591 ef = (elf_file_t)lf; 1592 es = (const Elf_Sym *)sym; 1593 if (es >= ef->symtab && es < ef->symtab + ef->nchains) { 1594 if (!see_local && ELF_ST_BIND(es->st_info) == STB_LOCAL) 1595 return (ENOENT); 1596 symval->name = ef->strtab + es->st_name; 1597 val = (caddr_t)ef->address + es->st_value; 1598 if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC) 1599 val = ((caddr_t (*)(void))val)(); 1600 symval->value = val; 1601 symval->size = es->st_size; 1602 return (0); 1603 } 1604 return (ENOENT); 1605 } 1606 1607 static int 1608 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, 1609 linker_symval_t *symval) 1610 { 1611 if (link_elf_leak_locals) 1612 return (link_elf_debug_symbol_values(lf, sym, symval)); 1613 return (link_elf_symbol_values1(lf, sym, symval, false)); 1614 } 1615 1616 static int 1617 link_elf_debug_symbol_values(linker_file_t lf, c_linker_sym_t sym, 1618 linker_symval_t *symval) 1619 { 1620 elf_file_t ef = (elf_file_t)lf; 1621 const Elf_Sym *es = (const Elf_Sym *)sym; 1622 caddr_t val; 1623 1624 if (link_elf_symbol_values1(lf, sym, symval, true) == 0) 1625 return (0); 1626 if (ef->symtab == ef->ddbsymtab) 1627 return (ENOENT); 1628 1629 if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) { 1630 symval->name = ef->ddbstrtab + es->st_name; 1631 val = (caddr_t)ef->address + es->st_value; 1632 if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC) 1633 val = ((caddr_t (*)(void))val)(); 1634 symval->value = val; 1635 symval->size = es->st_size; 1636 return (0); 1637 } 1638 return (ENOENT); 1639 } 1640 1641 static int 1642 link_elf_search_symbol(linker_file_t lf, caddr_t value, 1643 c_linker_sym_t *sym, long *diffp) 1644 { 1645 elf_file_t ef = (elf_file_t)lf; 1646 u_long off = (uintptr_t)(void *)value; 1647 u_long diff = off; 1648 u_long st_value; 1649 const Elf_Sym *es; 1650 const Elf_Sym *best = NULL; 1651 int i; 1652 1653 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) { 1654 if (es->st_name == 0) 1655 continue; 1656 st_value = es->st_value + (uintptr_t) (void *) ef->address; 1657 if (off >= st_value) { 1658 if (off - st_value < diff) { 1659 diff = off - st_value; 1660 best = es; 1661 if (diff == 0) 1662 break; 1663 } else if (off - st_value == diff) { 1664 best = es; 1665 } 1666 } 1667 } 1668 if (best == NULL) 1669 *diffp = off; 1670 else 1671 *diffp = diff; 1672 *sym = (c_linker_sym_t) best; 1673 1674 return (0); 1675 } 1676 1677 /* 1678 * Look up a linker set on an ELF system. 1679 */ 1680 static int 1681 link_elf_lookup_set(linker_file_t lf, const char *name, 1682 void ***startp, void ***stopp, int *countp) 1683 { 1684 c_linker_sym_t sym; 1685 linker_symval_t symval; 1686 char *setsym; 1687 void **start, **stop; 1688 int len, error = 0, count; 1689 1690 len = strlen(name) + sizeof("__start_set_"); /* sizeof includes \0 */ 1691 setsym = malloc(len, M_LINKER, M_WAITOK); 1692 1693 /* get address of first entry */ 1694 snprintf(setsym, len, "%s%s", "__start_set_", name); 1695 error = link_elf_lookup_symbol(lf, setsym, &sym); 1696 if (error != 0) 1697 goto out; 1698 link_elf_symbol_values(lf, sym, &symval); 1699 if (symval.value == 0) { 1700 error = ESRCH; 1701 goto out; 1702 } 1703 start = (void **)symval.value; 1704 1705 /* get address of last entry */ 1706 snprintf(setsym, len, "%s%s", "__stop_set_", name); 1707 error = link_elf_lookup_symbol(lf, setsym, &sym); 1708 if (error != 0) 1709 goto out; 1710 link_elf_symbol_values(lf, sym, &symval); 1711 if (symval.value == 0) { 1712 error = ESRCH; 1713 goto out; 1714 } 1715 stop = (void **)symval.value; 1716 1717 /* and the number of entries */ 1718 count = stop - start; 1719 1720 /* and copy out */ 1721 if (startp != NULL) 1722 *startp = start; 1723 if (stopp != NULL) 1724 *stopp = stop; 1725 if (countp != NULL) 1726 *countp = count; 1727 1728 out: 1729 free(setsym, M_LINKER); 1730 return (error); 1731 } 1732 1733 static int 1734 link_elf_each_function_name(linker_file_t file, 1735 int (*callback)(const char *, void *), void *opaque) 1736 { 1737 elf_file_t ef = (elf_file_t)file; 1738 const Elf_Sym *symp; 1739 int i, error; 1740 1741 /* Exhaustive search */ 1742 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1743 if (symp->st_value != 0 && 1744 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1745 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) { 1746 error = callback(ef->ddbstrtab + symp->st_name, opaque); 1747 if (error != 0) 1748 return (error); 1749 } 1750 } 1751 return (0); 1752 } 1753 1754 static int 1755 link_elf_each_function_nameval(linker_file_t file, 1756 linker_function_nameval_callback_t callback, void *opaque) 1757 { 1758 linker_symval_t symval; 1759 elf_file_t ef = (elf_file_t)file; 1760 const Elf_Sym *symp; 1761 int i, error; 1762 1763 /* Exhaustive search */ 1764 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1765 if (symp->st_value != 0 && 1766 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1767 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) { 1768 error = link_elf_debug_symbol_values(file, 1769 (c_linker_sym_t) symp, &symval); 1770 if (error == 0) 1771 error = callback(file, i, &symval, opaque); 1772 if (error != 0) 1773 return (error); 1774 } 1775 } 1776 return (0); 1777 } 1778 1779 const Elf_Sym * 1780 elf_get_sym(linker_file_t lf, Elf_Size symidx) 1781 { 1782 elf_file_t ef = (elf_file_t)lf; 1783 1784 if (symidx >= ef->nchains) 1785 return (NULL); 1786 return (ef->symtab + symidx); 1787 } 1788 1789 const char * 1790 elf_get_symname(linker_file_t lf, Elf_Size symidx) 1791 { 1792 elf_file_t ef = (elf_file_t)lf; 1793 const Elf_Sym *sym; 1794 1795 if (symidx >= ef->nchains) 1796 return (NULL); 1797 sym = ef->symtab + symidx; 1798 return (ef->strtab + sym->st_name); 1799 } 1800 1801 /* 1802 * Symbol lookup function that can be used when the symbol index is known (ie 1803 * in relocations). It uses the symbol index instead of doing a fully fledged 1804 * hash table based lookup when such is valid. For example for local symbols. 1805 * This is not only more efficient, it's also more correct. It's not always 1806 * the case that the symbol can be found through the hash table. 1807 */ 1808 static int 1809 elf_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *res) 1810 { 1811 elf_file_t ef = (elf_file_t)lf; 1812 const Elf_Sym *sym; 1813 const char *symbol; 1814 Elf_Addr addr, start, base; 1815 1816 /* Don't even try to lookup the symbol if the index is bogus. */ 1817 if (symidx >= ef->nchains) { 1818 *res = 0; 1819 return (EINVAL); 1820 } 1821 1822 sym = ef->symtab + symidx; 1823 1824 /* 1825 * Don't do a full lookup when the symbol is local. It may even 1826 * fail because it may not be found through the hash table. 1827 */ 1828 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) { 1829 /* Force lookup failure when we have an insanity. */ 1830 if (sym->st_shndx == SHN_UNDEF || sym->st_value == 0) { 1831 *res = 0; 1832 return (EINVAL); 1833 } 1834 *res = ((Elf_Addr)ef->address + sym->st_value); 1835 return (0); 1836 } 1837 1838 /* 1839 * XXX we can avoid doing a hash table based lookup for global 1840 * symbols as well. This however is not always valid, so we'll 1841 * just do it the hard way for now. Performance tweaks can 1842 * always be added. 1843 */ 1844 1845 symbol = ef->strtab + sym->st_name; 1846 1847 /* Force a lookup failure if the symbol name is bogus. */ 1848 if (*symbol == 0) { 1849 *res = 0; 1850 return (EINVAL); 1851 } 1852 1853 addr = ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps)); 1854 if (addr == 0 && ELF_ST_BIND(sym->st_info) != STB_WEAK) { 1855 *res = 0; 1856 return (EINVAL); 1857 } 1858 1859 if (elf_set_find(&set_pcpu_list, addr, &start, &base)) 1860 addr = addr - start + base; 1861 #ifdef VIMAGE 1862 else if (elf_set_find(&set_vnet_list, addr, &start, &base)) 1863 addr = addr - start + base; 1864 #endif 1865 *res = addr; 1866 return (0); 1867 } 1868 1869 static void 1870 link_elf_reloc_local(linker_file_t lf) 1871 { 1872 const Elf_Rel *rellim; 1873 const Elf_Rel *rel; 1874 const Elf_Rela *relalim; 1875 const Elf_Rela *rela; 1876 elf_file_t ef = (elf_file_t)lf; 1877 1878 /* Perform relocations without addend if there are any: */ 1879 if ((rel = ef->rel) != NULL) { 1880 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize); 1881 while (rel < rellim) { 1882 elf_reloc_local(lf, (Elf_Addr)ef->address, rel, 1883 ELF_RELOC_REL, elf_lookup); 1884 rel++; 1885 } 1886 } 1887 1888 /* Perform relocations with addend if there are any: */ 1889 if ((rela = ef->rela) != NULL) { 1890 relalim = (const Elf_Rela *) 1891 ((const char *)ef->rela + ef->relasize); 1892 while (rela < relalim) { 1893 elf_reloc_local(lf, (Elf_Addr)ef->address, rela, 1894 ELF_RELOC_RELA, elf_lookup); 1895 rela++; 1896 } 1897 } 1898 } 1899 1900 static long 1901 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab) 1902 { 1903 elf_file_t ef = (elf_file_t)lf; 1904 1905 *symtab = ef->ddbsymtab; 1906 1907 if (*symtab == NULL) 1908 return (0); 1909 1910 return (ef->ddbsymcnt); 1911 } 1912 1913 static long 1914 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab) 1915 { 1916 elf_file_t ef = (elf_file_t)lf; 1917 1918 *strtab = ef->ddbstrtab; 1919 1920 if (*strtab == NULL) 1921 return (0); 1922 1923 return (ef->ddbstrcnt); 1924 } 1925 1926 #if defined(__i386__) || defined(__amd64__) || defined(__aarch64__) || defined(__powerpc__) 1927 /* 1928 * Use this lookup routine when performing relocations early during boot. 1929 * The generic lookup routine depends on kobj, which is not initialized 1930 * at that point. 1931 */ 1932 static int 1933 elf_lookup_ifunc(linker_file_t lf, Elf_Size symidx, int deps __unused, 1934 Elf_Addr *res) 1935 { 1936 elf_file_t ef; 1937 const Elf_Sym *symp; 1938 caddr_t val; 1939 1940 ef = (elf_file_t)lf; 1941 symp = ef->symtab + symidx; 1942 if (ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC) { 1943 val = (caddr_t)ef->address + symp->st_value; 1944 *res = ((Elf_Addr (*)(void))val)(); 1945 return (0); 1946 } 1947 return (ENOENT); 1948 } 1949 1950 void 1951 link_elf_ireloc(caddr_t kmdp) 1952 { 1953 struct elf_file eff; 1954 elf_file_t ef; 1955 1956 ef = &eff; 1957 1958 bzero_early(ef, sizeof(*ef)); 1959 1960 ef->modptr = kmdp; 1961 ef->dynamic = (Elf_Dyn *)&_DYNAMIC; 1962 1963 #ifdef RELOCATABLE_KERNEL 1964 ef->address = (caddr_t) (__startkernel - KERNBASE); 1965 #else 1966 ef->address = 0; 1967 #endif 1968 parse_dynamic(ef); 1969 1970 link_elf_preload_parse_symbols(ef); 1971 relocate_file1(ef, elf_lookup_ifunc, elf_reloc, true); 1972 } 1973 1974 #if defined(__aarch64__) || defined(__amd64__) 1975 void 1976 link_elf_late_ireloc(void) 1977 { 1978 elf_file_t ef; 1979 1980 KASSERT(linker_kernel_file != NULL, 1981 ("link_elf_late_ireloc: No kernel linker file found")); 1982 ef = (elf_file_t)linker_kernel_file; 1983 1984 relocate_file1(ef, elf_lookup_ifunc, elf_reloc_late, true); 1985 } 1986 #endif 1987 #endif
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