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 #ifdef GPROF 38 #include <sys/gmon.h> 39 #endif 40 #include <sys/kernel.h> 41 #include <sys/lock.h> 42 #include <sys/malloc.h> 43 #ifdef SPARSE_MAPPING 44 #include <sys/mman.h> 45 #endif 46 #include <sys/mutex.h> 47 #include <sys/mount.h> 48 #include <sys/pcpu.h> 49 #include <sys/proc.h> 50 #include <sys/namei.h> 51 #include <sys/fcntl.h> 52 #include <sys/vnode.h> 53 #include <sys/linker.h> 54 #include <sys/sysctl.h> 55 56 #include <machine/elf.h> 57 58 #include <net/vnet.h> 59 60 #include <security/mac/mac_framework.h> 61 62 #include <vm/vm.h> 63 #include <vm/vm_param.h> 64 #ifdef SPARSE_MAPPING 65 #include <vm/vm_object.h> 66 #include <vm/vm_kern.h> 67 #include <vm/vm_extern.h> 68 #endif 69 #include <vm/pmap.h> 70 #include <vm/vm_map.h> 71 72 #include <sys/link_elf.h> 73 74 #include "linker_if.h" 75 76 #define MAXSEGS 4 77 78 typedef struct elf_file { 79 struct linker_file lf; /* Common fields */ 80 int preloaded; /* Was file pre-loaded */ 81 caddr_t address; /* Relocation address */ 82 #ifdef SPARSE_MAPPING 83 vm_object_t object; /* VM object to hold file pages */ 84 #endif 85 Elf_Dyn *dynamic; /* Symbol table etc. */ 86 Elf_Hashelt nbuckets; /* DT_HASH info */ 87 Elf_Hashelt nchains; 88 const Elf_Hashelt *buckets; 89 const Elf_Hashelt *chains; 90 caddr_t hash; 91 caddr_t strtab; /* DT_STRTAB */ 92 int strsz; /* DT_STRSZ */ 93 const Elf_Sym *symtab; /* DT_SYMTAB */ 94 Elf_Addr *got; /* DT_PLTGOT */ 95 const Elf_Rel *pltrel; /* DT_JMPREL */ 96 int pltrelsize; /* DT_PLTRELSZ */ 97 const Elf_Rela *pltrela; /* DT_JMPREL */ 98 int pltrelasize; /* DT_PLTRELSZ */ 99 const Elf_Rel *rel; /* DT_REL */ 100 int relsize; /* DT_RELSZ */ 101 const Elf_Rela *rela; /* DT_RELA */ 102 int relasize; /* DT_RELASZ */ 103 caddr_t modptr; 104 const Elf_Sym *ddbsymtab; /* The symbol table we are using */ 105 long ddbsymcnt; /* Number of symbols */ 106 caddr_t ddbstrtab; /* String table */ 107 long ddbstrcnt; /* number of bytes in string table */ 108 caddr_t symbase; /* malloc'ed symbold base */ 109 caddr_t strbase; /* malloc'ed string base */ 110 caddr_t ctftab; /* CTF table */ 111 long ctfcnt; /* number of bytes in CTF table */ 112 caddr_t ctfoff; /* CTF offset table */ 113 caddr_t typoff; /* Type offset table */ 114 long typlen; /* Number of type entries. */ 115 Elf_Addr pcpu_start; /* Pre-relocation pcpu set start. */ 116 Elf_Addr pcpu_stop; /* Pre-relocation pcpu set stop. */ 117 Elf_Addr pcpu_base; /* Relocated pcpu set address. */ 118 #ifdef VIMAGE 119 Elf_Addr vnet_start; /* Pre-relocation vnet set start. */ 120 Elf_Addr vnet_stop; /* Pre-relocation vnet set stop. */ 121 Elf_Addr vnet_base; /* Relocated vnet set address. */ 122 #endif 123 #ifdef GDB 124 struct link_map gdb; /* hooks for gdb */ 125 #endif 126 } *elf_file_t; 127 128 struct elf_set { 129 Elf_Addr es_start; 130 Elf_Addr es_stop; 131 Elf_Addr es_base; 132 TAILQ_ENTRY(elf_set) es_link; 133 }; 134 135 TAILQ_HEAD(elf_set_head, elf_set); 136 137 #include <kern/kern_ctf.c> 138 139 static int link_elf_link_common_finish(linker_file_t); 140 static int link_elf_link_preload(linker_class_t cls, 141 const char *, linker_file_t *); 142 static int link_elf_link_preload_finish(linker_file_t); 143 static int link_elf_load_file(linker_class_t, const char *, 144 linker_file_t *); 145 static int link_elf_lookup_symbol(linker_file_t, const char *, 146 c_linker_sym_t *); 147 static int link_elf_lookup_debug_symbol(linker_file_t, const char *, 148 c_linker_sym_t *); 149 static int link_elf_symbol_values(linker_file_t, c_linker_sym_t, 150 linker_symval_t *); 151 static int link_elf_debug_symbol_values(linker_file_t, c_linker_sym_t, 152 linker_symval_t*); 153 static int link_elf_search_symbol(linker_file_t, caddr_t, 154 c_linker_sym_t *, long *); 155 156 static void link_elf_unload_file(linker_file_t); 157 static void link_elf_unload_preload(linker_file_t); 158 static int link_elf_lookup_set(linker_file_t, const char *, 159 void ***, void ***, int *); 160 static int link_elf_each_function_name(linker_file_t, 161 int (*)(const char *, void *), void *); 162 static int link_elf_each_function_nameval(linker_file_t, 163 linker_function_nameval_callback_t, void *); 164 static void link_elf_reloc_local(linker_file_t); 165 static long link_elf_symtab_get(linker_file_t, const Elf_Sym **); 166 static long link_elf_strtab_get(linker_file_t, caddr_t *); 167 static int elf_lookup(linker_file_t, Elf_Size, int, Elf_Addr *); 168 169 static kobj_method_t link_elf_methods[] = { 170 KOBJMETHOD(linker_lookup_symbol, link_elf_lookup_symbol), 171 KOBJMETHOD(linker_lookup_debug_symbol, link_elf_lookup_debug_symbol), 172 KOBJMETHOD(linker_symbol_values, link_elf_symbol_values), 173 KOBJMETHOD(linker_debug_symbol_values, link_elf_debug_symbol_values), 174 KOBJMETHOD(linker_search_symbol, link_elf_search_symbol), 175 KOBJMETHOD(linker_unload, link_elf_unload_file), 176 KOBJMETHOD(linker_load_file, link_elf_load_file), 177 KOBJMETHOD(linker_link_preload, link_elf_link_preload), 178 KOBJMETHOD(linker_link_preload_finish, link_elf_link_preload_finish), 179 KOBJMETHOD(linker_lookup_set, link_elf_lookup_set), 180 KOBJMETHOD(linker_each_function_name, link_elf_each_function_name), 181 KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval), 182 KOBJMETHOD(linker_ctf_get, link_elf_ctf_get), 183 KOBJMETHOD(linker_symtab_get, link_elf_symtab_get), 184 KOBJMETHOD(linker_strtab_get, link_elf_strtab_get), 185 KOBJMETHOD_END 186 }; 187 188 static struct linker_class link_elf_class = { 189 #if ELF_TARG_CLASS == ELFCLASS32 190 "elf32", 191 #else 192 "elf64", 193 #endif 194 link_elf_methods, sizeof(struct elf_file) 195 }; 196 197 static bool link_elf_leak_locals = true; 198 SYSCTL_BOOL(_debug, OID_AUTO, link_elf_leak_locals, 199 CTLFLAG_RWTUN, &link_elf_leak_locals, 0, 200 "Allow local symbols to participate in global module symbol resolution"); 201 202 typedef int (*elf_reloc_fn)(linker_file_t lf, Elf_Addr relocbase, 203 const void *data, int type, elf_lookup_fn lookup); 204 205 static int parse_dynamic(elf_file_t); 206 static int relocate_file(elf_file_t); 207 static int relocate_file1(elf_file_t ef, elf_lookup_fn lookup, 208 elf_reloc_fn reloc, bool ifuncs); 209 static int link_elf_preload_parse_symbols(elf_file_t); 210 211 static struct elf_set_head set_pcpu_list; 212 #ifdef VIMAGE 213 static struct elf_set_head set_vnet_list; 214 #endif 215 216 static void 217 elf_set_add(struct elf_set_head *list, Elf_Addr start, Elf_Addr stop, Elf_Addr base) 218 { 219 struct elf_set *set, *iter; 220 221 set = malloc(sizeof(*set), M_LINKER, M_WAITOK); 222 set->es_start = start; 223 set->es_stop = stop; 224 set->es_base = base; 225 226 TAILQ_FOREACH(iter, list, es_link) { 227 KASSERT((set->es_start < iter->es_start && set->es_stop < iter->es_stop) || 228 (set->es_start > iter->es_start && set->es_stop > iter->es_stop), 229 ("linker sets intersection: to insert: 0x%jx-0x%jx; inserted: 0x%jx-0x%jx", 230 (uintmax_t)set->es_start, (uintmax_t)set->es_stop, 231 (uintmax_t)iter->es_start, (uintmax_t)iter->es_stop)); 232 233 if (iter->es_start > set->es_start) { 234 TAILQ_INSERT_BEFORE(iter, set, es_link); 235 break; 236 } 237 } 238 239 if (iter == NULL) 240 TAILQ_INSERT_TAIL(list, set, es_link); 241 } 242 243 static int 244 elf_set_find(struct elf_set_head *list, Elf_Addr addr, Elf_Addr *start, Elf_Addr *base) 245 { 246 struct elf_set *set; 247 248 TAILQ_FOREACH(set, list, es_link) { 249 if (addr < set->es_start) 250 return (0); 251 if (addr < set->es_stop) { 252 *start = set->es_start; 253 *base = set->es_base; 254 return (1); 255 } 256 } 257 258 return (0); 259 } 260 261 static void 262 elf_set_delete(struct elf_set_head *list, Elf_Addr start) 263 { 264 struct elf_set *set; 265 266 TAILQ_FOREACH(set, list, es_link) { 267 if (start < set->es_start) 268 break; 269 if (start == set->es_start) { 270 TAILQ_REMOVE(list, set, es_link); 271 free(set, M_LINKER); 272 return; 273 } 274 } 275 KASSERT(0, ("deleting unknown linker set (start = 0x%jx)", 276 (uintmax_t)start)); 277 } 278 279 #ifdef GDB 280 static void r_debug_state(struct r_debug *, struct link_map *); 281 282 /* 283 * A list of loaded modules for GDB to use for loading symbols. 284 */ 285 struct r_debug r_debug; 286 287 #define GDB_STATE(s) do { \ 288 r_debug.r_state = s; r_debug_state(NULL, NULL); \ 289 } while (0) 290 291 /* 292 * Function for the debugger to set a breakpoint on to gain control. 293 */ 294 static void 295 r_debug_state(struct r_debug *dummy_one __unused, 296 struct link_map *dummy_two __unused) 297 { 298 } 299 300 static void 301 link_elf_add_gdb(struct link_map *l) 302 { 303 struct link_map *prev; 304 305 l->l_next = NULL; 306 307 if (r_debug.r_map == NULL) { 308 /* Add first. */ 309 l->l_prev = NULL; 310 r_debug.r_map = l; 311 } else { 312 /* Append to list. */ 313 for (prev = r_debug.r_map; 314 prev->l_next != NULL; 315 prev = prev->l_next) 316 ; 317 l->l_prev = prev; 318 prev->l_next = l; 319 } 320 } 321 322 static void 323 link_elf_delete_gdb(struct link_map *l) 324 { 325 if (l->l_prev == NULL) { 326 /* Remove first. */ 327 if ((r_debug.r_map = l->l_next) != NULL) 328 l->l_next->l_prev = NULL; 329 } else { 330 /* Remove any but first. */ 331 if ((l->l_prev->l_next = l->l_next) != NULL) 332 l->l_next->l_prev = l->l_prev; 333 } 334 } 335 #endif /* GDB */ 336 337 /* 338 * The kernel symbol table starts here. 339 */ 340 extern struct _dynamic _DYNAMIC; 341 342 static void 343 link_elf_error(const char *filename, const char *s) 344 { 345 if (filename == NULL) 346 printf("kldload: %s\n", s); 347 else 348 printf("kldload: %s: %s\n", filename, s); 349 } 350 351 static void 352 link_elf_invoke_ctors(caddr_t addr, size_t size) 353 { 354 void (**ctor)(void); 355 size_t i, cnt; 356 357 if (addr == NULL || size == 0) 358 return; 359 cnt = size / sizeof(*ctor); 360 ctor = (void *)addr; 361 for (i = 0; i < cnt; i++) { 362 if (ctor[i] != NULL) 363 (*ctor[i])(); 364 } 365 } 366 367 /* 368 * Actions performed after linking/loading both the preloaded kernel and any 369 * modules; whether preloaded or dynamicly loaded. 370 */ 371 static int 372 link_elf_link_common_finish(linker_file_t lf) 373 { 374 #ifdef GDB 375 elf_file_t ef = (elf_file_t)lf; 376 char *newfilename; 377 #endif 378 int error; 379 380 /* Notify MD code that a module is being loaded. */ 381 error = elf_cpu_load_file(lf); 382 if (error != 0) 383 return (error); 384 385 #ifdef GDB 386 GDB_STATE(RT_ADD); 387 ef->gdb.l_addr = lf->address; 388 newfilename = malloc(strlen(lf->filename) + 1, M_LINKER, M_WAITOK); 389 strcpy(newfilename, lf->filename); 390 ef->gdb.l_name = newfilename; 391 ef->gdb.l_ld = ef->dynamic; 392 link_elf_add_gdb(&ef->gdb); 393 GDB_STATE(RT_CONSISTENT); 394 #endif 395 396 /* Invoke .ctors */ 397 link_elf_invoke_ctors(lf->ctors_addr, lf->ctors_size); 398 return (0); 399 } 400 401 #ifdef RELOCATABLE_KERNEL 402 /* 403 * __startkernel and __endkernel are symbols set up as relocation canaries. 404 * 405 * They are defined in locore to reference linker script symbols at the 406 * beginning and end of the LOAD area. This has the desired side effect of 407 * giving us variables that have relative relocations pointing at them, so 408 * relocation of the kernel object will cause the variables to be updated 409 * automatically by the runtime linker when we initialize. 410 * 411 * There are two main reasons to relocate the kernel: 412 * 1) If the loader needed to load the kernel at an alternate load address. 413 * 2) If the kernel is switching address spaces on machines like POWER9 414 * under Radix where the high bits of the effective address are used to 415 * differentiate between hypervisor, host, guest, and problem state. 416 */ 417 extern vm_offset_t __startkernel, __endkernel; 418 #endif 419 420 static unsigned long kern_relbase = KERNBASE; 421 422 SYSCTL_ULONG(_kern, OID_AUTO, base_address, CTLFLAG_RD, 423 SYSCTL_NULL_ULONG_PTR, KERNBASE, "Kernel base address"); 424 SYSCTL_ULONG(_kern, OID_AUTO, relbase_address, CTLFLAG_RD, 425 &kern_relbase, 0, "Kernel relocated base address"); 426 427 static void 428 link_elf_init(void* arg) 429 { 430 Elf_Dyn *dp; 431 Elf_Addr *ctors_addrp; 432 Elf_Size *ctors_sizep; 433 caddr_t modptr, baseptr, sizeptr; 434 elf_file_t ef; 435 const char *modname; 436 437 linker_add_class(&link_elf_class); 438 439 dp = (Elf_Dyn *)&_DYNAMIC; 440 modname = NULL; 441 modptr = preload_search_by_type("elf" __XSTRING(__ELF_WORD_SIZE) " kernel"); 442 if (modptr == NULL) 443 modptr = preload_search_by_type("elf kernel"); 444 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 445 if (modname == NULL) 446 modname = "kernel"; 447 linker_kernel_file = linker_make_file(modname, &link_elf_class); 448 if (linker_kernel_file == NULL) 449 panic("%s: Can't create linker structures for kernel", 450 __func__); 451 452 ef = (elf_file_t) linker_kernel_file; 453 ef->preloaded = 1; 454 #ifdef RELOCATABLE_KERNEL 455 /* Compute relative displacement */ 456 ef->address = (caddr_t) (__startkernel - KERNBASE); 457 #else 458 ef->address = 0; 459 #endif 460 #ifdef SPARSE_MAPPING 461 ef->object = NULL; 462 #endif 463 ef->dynamic = dp; 464 465 if (dp != NULL) 466 parse_dynamic(ef); 467 #ifdef RELOCATABLE_KERNEL 468 linker_kernel_file->address = (caddr_t)__startkernel; 469 linker_kernel_file->size = (intptr_t)(__endkernel - __startkernel); 470 kern_relbase = (unsigned long)__startkernel; 471 #else 472 linker_kernel_file->address += KERNBASE; 473 linker_kernel_file->size = -(intptr_t)linker_kernel_file->address; 474 #endif 475 476 if (modptr != NULL) { 477 ef->modptr = modptr; 478 baseptr = preload_search_info(modptr, MODINFO_ADDR); 479 if (baseptr != NULL) 480 linker_kernel_file->address = *(caddr_t *)baseptr; 481 sizeptr = preload_search_info(modptr, MODINFO_SIZE); 482 if (sizeptr != NULL) 483 linker_kernel_file->size = *(size_t *)sizeptr; 484 ctors_addrp = (Elf_Addr *)preload_search_info(modptr, 485 MODINFO_METADATA | MODINFOMD_CTORS_ADDR); 486 ctors_sizep = (Elf_Size *)preload_search_info(modptr, 487 MODINFO_METADATA | MODINFOMD_CTORS_SIZE); 488 if (ctors_addrp != NULL && ctors_sizep != NULL) { 489 linker_kernel_file->ctors_addr = ef->address + 490 *ctors_addrp; 491 linker_kernel_file->ctors_size = *ctors_sizep; 492 } 493 } 494 (void)link_elf_preload_parse_symbols(ef); 495 496 #ifdef GDB 497 r_debug.r_map = NULL; 498 r_debug.r_brk = r_debug_state; 499 r_debug.r_state = RT_CONSISTENT; 500 #endif 501 502 (void)link_elf_link_common_finish(linker_kernel_file); 503 linker_kernel_file->flags |= LINKER_FILE_LINKED; 504 TAILQ_INIT(&set_pcpu_list); 505 #ifdef VIMAGE 506 TAILQ_INIT(&set_vnet_list); 507 #endif 508 } 509 510 SYSINIT(link_elf, SI_SUB_KLD, SI_ORDER_THIRD, link_elf_init, NULL); 511 512 static int 513 link_elf_preload_parse_symbols(elf_file_t ef) 514 { 515 caddr_t pointer; 516 caddr_t ssym, esym, base; 517 caddr_t strtab; 518 int strcnt; 519 Elf_Sym *symtab; 520 int symcnt; 521 522 if (ef->modptr == NULL) 523 return (0); 524 pointer = preload_search_info(ef->modptr, 525 MODINFO_METADATA | MODINFOMD_SSYM); 526 if (pointer == NULL) 527 return (0); 528 ssym = *(caddr_t *)pointer; 529 pointer = preload_search_info(ef->modptr, 530 MODINFO_METADATA | MODINFOMD_ESYM); 531 if (pointer == NULL) 532 return (0); 533 esym = *(caddr_t *)pointer; 534 535 base = ssym; 536 537 symcnt = *(long *)base; 538 base += sizeof(long); 539 symtab = (Elf_Sym *)base; 540 base += roundup(symcnt, sizeof(long)); 541 542 if (base > esym || base < ssym) { 543 printf("Symbols are corrupt!\n"); 544 return (EINVAL); 545 } 546 547 strcnt = *(long *)base; 548 base += sizeof(long); 549 strtab = base; 550 base += roundup(strcnt, sizeof(long)); 551 552 if (base > esym || base < ssym) { 553 printf("Symbols are corrupt!\n"); 554 return (EINVAL); 555 } 556 557 ef->ddbsymtab = symtab; 558 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym); 559 ef->ddbstrtab = strtab; 560 ef->ddbstrcnt = strcnt; 561 562 return (0); 563 } 564 565 static int 566 parse_dynamic(elf_file_t ef) 567 { 568 Elf_Dyn *dp; 569 int plttype = DT_REL; 570 571 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) { 572 switch (dp->d_tag) { 573 case DT_HASH: 574 { 575 /* From src/libexec/rtld-elf/rtld.c */ 576 const Elf_Hashelt *hashtab = (const Elf_Hashelt *) 577 (ef->address + dp->d_un.d_ptr); 578 ef->nbuckets = hashtab[0]; 579 ef->nchains = hashtab[1]; 580 ef->buckets = hashtab + 2; 581 ef->chains = ef->buckets + ef->nbuckets; 582 break; 583 } 584 case DT_STRTAB: 585 ef->strtab = (caddr_t) (ef->address + dp->d_un.d_ptr); 586 break; 587 case DT_STRSZ: 588 ef->strsz = dp->d_un.d_val; 589 break; 590 case DT_SYMTAB: 591 ef->symtab = (Elf_Sym*) (ef->address + dp->d_un.d_ptr); 592 break; 593 case DT_SYMENT: 594 if (dp->d_un.d_val != sizeof(Elf_Sym)) 595 return (ENOEXEC); 596 break; 597 case DT_PLTGOT: 598 ef->got = (Elf_Addr *) (ef->address + dp->d_un.d_ptr); 599 break; 600 case DT_REL: 601 ef->rel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr); 602 break; 603 case DT_RELSZ: 604 ef->relsize = dp->d_un.d_val; 605 break; 606 case DT_RELENT: 607 if (dp->d_un.d_val != sizeof(Elf_Rel)) 608 return (ENOEXEC); 609 break; 610 case DT_JMPREL: 611 ef->pltrel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr); 612 break; 613 case DT_PLTRELSZ: 614 ef->pltrelsize = dp->d_un.d_val; 615 break; 616 case DT_RELA: 617 ef->rela = (const Elf_Rela *) (ef->address + dp->d_un.d_ptr); 618 break; 619 case DT_RELASZ: 620 ef->relasize = dp->d_un.d_val; 621 break; 622 case DT_RELAENT: 623 if (dp->d_un.d_val != sizeof(Elf_Rela)) 624 return (ENOEXEC); 625 break; 626 case DT_PLTREL: 627 plttype = dp->d_un.d_val; 628 if (plttype != DT_REL && plttype != DT_RELA) 629 return (ENOEXEC); 630 break; 631 #ifdef GDB 632 case DT_DEBUG: 633 dp->d_un.d_ptr = (Elf_Addr)&r_debug; 634 break; 635 #endif 636 } 637 } 638 639 if (plttype == DT_RELA) { 640 ef->pltrela = (const Elf_Rela *)ef->pltrel; 641 ef->pltrel = NULL; 642 ef->pltrelasize = ef->pltrelsize; 643 ef->pltrelsize = 0; 644 } 645 646 ef->ddbsymtab = ef->symtab; 647 ef->ddbsymcnt = ef->nchains; 648 ef->ddbstrtab = ef->strtab; 649 ef->ddbstrcnt = ef->strsz; 650 651 return elf_cpu_parse_dynamic(ef->address, ef->dynamic); 652 } 653 654 #define LS_PADDING 0x90909090 655 static int 656 parse_dpcpu(elf_file_t ef) 657 { 658 int error, size; 659 #if defined(__i386__) 660 uint32_t pad; 661 #endif 662 663 ef->pcpu_start = 0; 664 ef->pcpu_stop = 0; 665 error = link_elf_lookup_set(&ef->lf, "pcpu", (void ***)&ef->pcpu_start, 666 (void ***)&ef->pcpu_stop, NULL); 667 /* Error just means there is no pcpu set to relocate. */ 668 if (error != 0) 669 return (0); 670 size = (uintptr_t)ef->pcpu_stop - (uintptr_t)ef->pcpu_start; 671 /* Empty set? */ 672 if (size < 1) 673 return (0); 674 #if defined(__i386__) 675 /* In case we do find __start/stop_set_ symbols double-check. */ 676 if (size < 4) { 677 uprintf("Kernel module '%s' must be recompiled with " 678 "linker script\n", ef->lf.pathname); 679 return (ENOEXEC); 680 } 681 682 /* Padding from linker-script correct? */ 683 pad = *(uint32_t *)((uintptr_t)ef->pcpu_stop - sizeof(pad)); 684 if (pad != LS_PADDING) { 685 uprintf("Kernel module '%s' must be recompiled with " 686 "linker script, invalid padding %#04x (%#04x)\n", 687 ef->lf.pathname, pad, LS_PADDING); 688 return (ENOEXEC); 689 } 690 /* If we only have valid padding, nothing to do. */ 691 if (size == 4) 692 return (0); 693 #endif 694 /* 695 * Allocate space in the primary pcpu area. Copy in our 696 * initialization from the data section and then initialize 697 * all per-cpu storage from that. 698 */ 699 ef->pcpu_base = (Elf_Addr)(uintptr_t)dpcpu_alloc(size); 700 if (ef->pcpu_base == 0) { 701 printf("%s: pcpu module space is out of space; " 702 "cannot allocate %d for %s\n", 703 __func__, size, ef->lf.pathname); 704 return (ENOSPC); 705 } 706 memcpy((void *)ef->pcpu_base, (void *)ef->pcpu_start, size); 707 dpcpu_copy((void *)ef->pcpu_base, size); 708 elf_set_add(&set_pcpu_list, ef->pcpu_start, ef->pcpu_stop, 709 ef->pcpu_base); 710 711 return (0); 712 } 713 714 #ifdef VIMAGE 715 static int 716 parse_vnet(elf_file_t ef) 717 { 718 int error, size; 719 #if defined(__i386__) 720 uint32_t pad; 721 #endif 722 723 ef->vnet_start = 0; 724 ef->vnet_stop = 0; 725 error = link_elf_lookup_set(&ef->lf, "vnet", (void ***)&ef->vnet_start, 726 (void ***)&ef->vnet_stop, NULL); 727 /* Error just means there is no vnet data set to relocate. */ 728 if (error != 0) 729 return (0); 730 size = (uintptr_t)ef->vnet_stop - (uintptr_t)ef->vnet_start; 731 /* Empty set? */ 732 if (size < 1) 733 return (0); 734 #if defined(__i386__) 735 /* In case we do find __start/stop_set_ symbols double-check. */ 736 if (size < 4) { 737 uprintf("Kernel module '%s' must be recompiled with " 738 "linker script\n", ef->lf.pathname); 739 return (ENOEXEC); 740 } 741 742 /* Padding from linker-script correct? */ 743 pad = *(uint32_t *)((uintptr_t)ef->vnet_stop - sizeof(pad)); 744 if (pad != LS_PADDING) { 745 uprintf("Kernel module '%s' must be recompiled with " 746 "linker script, invalid padding %#04x (%#04x)\n", 747 ef->lf.pathname, pad, LS_PADDING); 748 return (ENOEXEC); 749 } 750 /* If we only have valid padding, nothing to do. */ 751 if (size == 4) 752 return (0); 753 #endif 754 /* 755 * Allocate space in the primary vnet area. Copy in our 756 * initialization from the data section and then initialize 757 * all per-vnet storage from that. 758 */ 759 ef->vnet_base = (Elf_Addr)(uintptr_t)vnet_data_alloc(size); 760 if (ef->vnet_base == 0) { 761 printf("%s: vnet module space is out of space; " 762 "cannot allocate %d for %s\n", 763 __func__, size, ef->lf.pathname); 764 return (ENOSPC); 765 } 766 memcpy((void *)ef->vnet_base, (void *)ef->vnet_start, size); 767 vnet_data_copy((void *)ef->vnet_base, size); 768 elf_set_add(&set_vnet_list, ef->vnet_start, ef->vnet_stop, 769 ef->vnet_base); 770 771 return (0); 772 } 773 #endif 774 #undef LS_PADDING 775 776 /* 777 * Apply the specified protection to the loadable segments of a preloaded linker 778 * file. 779 */ 780 static int 781 preload_protect(elf_file_t ef, vm_prot_t prot) 782 { 783 #if defined(__aarch64__) || defined(__amd64__) 784 Elf_Ehdr *hdr; 785 Elf_Phdr *phdr, *phlimit; 786 vm_prot_t nprot; 787 int error; 788 789 error = 0; 790 hdr = (Elf_Ehdr *)ef->address; 791 phdr = (Elf_Phdr *)(ef->address + hdr->e_phoff); 792 phlimit = phdr + hdr->e_phnum; 793 for (; phdr < phlimit; phdr++) { 794 if (phdr->p_type != PT_LOAD) 795 continue; 796 797 nprot = prot | VM_PROT_READ; 798 if ((phdr->p_flags & PF_W) != 0) 799 nprot |= VM_PROT_WRITE; 800 if ((phdr->p_flags & PF_X) != 0) 801 nprot |= VM_PROT_EXECUTE; 802 error = pmap_change_prot((vm_offset_t)ef->address + 803 phdr->p_vaddr, round_page(phdr->p_memsz), nprot); 804 if (error != 0) 805 break; 806 } 807 return (error); 808 #else 809 return (0); 810 #endif 811 } 812 813 #ifdef __arm__ 814 /* 815 * Locate the ARM exception/unwind table info for DDB and stack(9) use by 816 * searching for the section header that describes it. There may be no unwind 817 * info, for example in a module containing only data. 818 */ 819 static void 820 link_elf_locate_exidx(linker_file_t lf, Elf_Shdr *shdr, int nhdr) 821 { 822 int i; 823 824 for (i = 0; i < nhdr; i++) { 825 if (shdr[i].sh_type == SHT_ARM_EXIDX) { 826 lf->exidx_addr = shdr[i].sh_addr + lf->address; 827 lf->exidx_size = shdr[i].sh_size; 828 break; 829 } 830 } 831 } 832 833 /* 834 * Locate the section headers metadata in a preloaded module, then use it to 835 * locate the exception/unwind table in the module. The size of the metadata 836 * block is stored in a uint32 word immediately before the data itself, and a 837 * comment in preload_search_info() says it is safe to rely on that. 838 */ 839 static void 840 link_elf_locate_exidx_preload(struct linker_file *lf, caddr_t modptr) 841 { 842 uint32_t *modinfo; 843 Elf_Shdr *shdr; 844 uint32_t nhdr; 845 846 modinfo = (uint32_t *)preload_search_info(modptr, 847 MODINFO_METADATA | MODINFOMD_SHDR); 848 if (modinfo != NULL) { 849 shdr = (Elf_Shdr *)modinfo; 850 nhdr = modinfo[-1] / sizeof(Elf_Shdr); 851 link_elf_locate_exidx(lf, shdr, nhdr); 852 } 853 } 854 855 #endif /* __arm__ */ 856 857 static int 858 link_elf_link_preload(linker_class_t cls, const char *filename, 859 linker_file_t *result) 860 { 861 Elf_Addr *ctors_addrp; 862 Elf_Size *ctors_sizep; 863 caddr_t modptr, baseptr, sizeptr, dynptr; 864 char *type; 865 elf_file_t ef; 866 linker_file_t lf; 867 int error; 868 vm_offset_t dp; 869 870 /* Look to see if we have the file preloaded */ 871 modptr = preload_search_by_name(filename); 872 if (modptr == NULL) 873 return (ENOENT); 874 875 type = (char *)preload_search_info(modptr, MODINFO_TYPE); 876 baseptr = preload_search_info(modptr, MODINFO_ADDR); 877 sizeptr = preload_search_info(modptr, MODINFO_SIZE); 878 dynptr = preload_search_info(modptr, 879 MODINFO_METADATA | MODINFOMD_DYNAMIC); 880 if (type == NULL || 881 (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) " module") != 0 && 882 strcmp(type, "elf module") != 0)) 883 return (EFTYPE); 884 if (baseptr == NULL || sizeptr == NULL || dynptr == NULL) 885 return (EINVAL); 886 887 lf = linker_make_file(filename, &link_elf_class); 888 if (lf == NULL) 889 return (ENOMEM); 890 891 ef = (elf_file_t) lf; 892 ef->preloaded = 1; 893 ef->modptr = modptr; 894 ef->address = *(caddr_t *)baseptr; 895 #ifdef SPARSE_MAPPING 896 ef->object = NULL; 897 #endif 898 dp = (vm_offset_t)ef->address + *(vm_offset_t *)dynptr; 899 ef->dynamic = (Elf_Dyn *)dp; 900 lf->address = ef->address; 901 lf->size = *(size_t *)sizeptr; 902 903 ctors_addrp = (Elf_Addr *)preload_search_info(modptr, 904 MODINFO_METADATA | MODINFOMD_CTORS_ADDR); 905 ctors_sizep = (Elf_Size *)preload_search_info(modptr, 906 MODINFO_METADATA | MODINFOMD_CTORS_SIZE); 907 if (ctors_addrp != NULL && ctors_sizep != NULL) { 908 lf->ctors_addr = ef->address + *ctors_addrp; 909 lf->ctors_size = *ctors_sizep; 910 } 911 912 #ifdef __arm__ 913 link_elf_locate_exidx_preload(lf, modptr); 914 #endif 915 916 error = parse_dynamic(ef); 917 if (error == 0) 918 error = parse_dpcpu(ef); 919 #ifdef VIMAGE 920 if (error == 0) 921 error = parse_vnet(ef); 922 #endif 923 if (error == 0) 924 error = preload_protect(ef, VM_PROT_ALL); 925 if (error != 0) { 926 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 927 return (error); 928 } 929 link_elf_reloc_local(lf); 930 *result = lf; 931 return (0); 932 } 933 934 static int 935 link_elf_link_preload_finish(linker_file_t lf) 936 { 937 elf_file_t ef; 938 int error; 939 940 ef = (elf_file_t) lf; 941 error = relocate_file(ef); 942 if (error == 0) 943 error = preload_protect(ef, VM_PROT_NONE); 944 if (error != 0) 945 return (error); 946 (void)link_elf_preload_parse_symbols(ef); 947 948 return (link_elf_link_common_finish(lf)); 949 } 950 951 static int 952 link_elf_load_file(linker_class_t cls, const char* filename, 953 linker_file_t* result) 954 { 955 struct nameidata nd; 956 struct thread* td = curthread; /* XXX */ 957 Elf_Ehdr *hdr; 958 caddr_t firstpage, segbase; 959 int nbytes, i; 960 Elf_Phdr *phdr; 961 Elf_Phdr *phlimit; 962 Elf_Phdr *segs[MAXSEGS]; 963 int nsegs; 964 Elf_Phdr *phdyn; 965 caddr_t mapbase; 966 size_t mapsize; 967 Elf_Addr base_vaddr; 968 Elf_Addr base_vlimit; 969 int error = 0; 970 ssize_t resid; 971 int flags; 972 elf_file_t ef; 973 linker_file_t lf; 974 Elf_Shdr *shdr; 975 int symtabindex; 976 int symstrindex; 977 int shstrindex; 978 int symcnt; 979 int strcnt; 980 char *shstrs; 981 982 shdr = NULL; 983 lf = NULL; 984 shstrs = NULL; 985 986 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename, td); 987 flags = FREAD; 988 error = vn_open(&nd, &flags, 0, NULL); 989 if (error != 0) 990 return (error); 991 NDFREE(&nd, NDF_ONLY_PNBUF); 992 if (nd.ni_vp->v_type != VREG) { 993 error = ENOEXEC; 994 firstpage = NULL; 995 goto out; 996 } 997 #ifdef MAC 998 error = mac_kld_check_load(curthread->td_ucred, nd.ni_vp); 999 if (error != 0) { 1000 firstpage = NULL; 1001 goto out; 1002 } 1003 #endif 1004 1005 /* 1006 * Read the elf header from the file. 1007 */ 1008 firstpage = malloc(PAGE_SIZE, M_LINKER, M_WAITOK); 1009 hdr = (Elf_Ehdr *)firstpage; 1010 error = vn_rdwr(UIO_READ, nd.ni_vp, firstpage, PAGE_SIZE, 0, 1011 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1012 &resid, td); 1013 nbytes = PAGE_SIZE - resid; 1014 if (error != 0) 1015 goto out; 1016 1017 if (!IS_ELF(*hdr)) { 1018 error = ENOEXEC; 1019 goto out; 1020 } 1021 1022 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 1023 hdr->e_ident[EI_DATA] != ELF_TARG_DATA) { 1024 link_elf_error(filename, "Unsupported file layout"); 1025 error = ENOEXEC; 1026 goto out; 1027 } 1028 if (hdr->e_ident[EI_VERSION] != EV_CURRENT || 1029 hdr->e_version != EV_CURRENT) { 1030 link_elf_error(filename, "Unsupported file version"); 1031 error = ENOEXEC; 1032 goto out; 1033 } 1034 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) { 1035 error = ENOSYS; 1036 goto out; 1037 } 1038 if (hdr->e_machine != ELF_TARG_MACH) { 1039 link_elf_error(filename, "Unsupported machine"); 1040 error = ENOEXEC; 1041 goto out; 1042 } 1043 1044 /* 1045 * We rely on the program header being in the first page. 1046 * This is not strictly required by the ABI specification, but 1047 * it seems to always true in practice. And, it simplifies 1048 * things considerably. 1049 */ 1050 if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) && 1051 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) && 1052 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes))) 1053 link_elf_error(filename, "Unreadable program headers"); 1054 1055 /* 1056 * Scan the program header entries, and save key information. 1057 * 1058 * We rely on there being exactly two load segments, text and data, 1059 * in that order. 1060 */ 1061 phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff); 1062 phlimit = phdr + hdr->e_phnum; 1063 nsegs = 0; 1064 phdyn = NULL; 1065 while (phdr < phlimit) { 1066 switch (phdr->p_type) { 1067 case PT_LOAD: 1068 if (nsegs == MAXSEGS) { 1069 link_elf_error(filename, "Too many sections"); 1070 error = ENOEXEC; 1071 goto out; 1072 } 1073 /* 1074 * XXX: We just trust they come in right order ?? 1075 */ 1076 segs[nsegs] = phdr; 1077 ++nsegs; 1078 break; 1079 1080 case PT_DYNAMIC: 1081 phdyn = phdr; 1082 break; 1083 1084 case PT_INTERP: 1085 error = ENOSYS; 1086 goto out; 1087 } 1088 1089 ++phdr; 1090 } 1091 if (phdyn == NULL) { 1092 link_elf_error(filename, "Object is not dynamically-linked"); 1093 error = ENOEXEC; 1094 goto out; 1095 } 1096 if (nsegs == 0) { 1097 link_elf_error(filename, "No sections"); 1098 error = ENOEXEC; 1099 goto out; 1100 } 1101 1102 /* 1103 * Allocate the entire address space of the object, to stake 1104 * out our contiguous region, and to establish the base 1105 * address for relocation. 1106 */ 1107 base_vaddr = trunc_page(segs[0]->p_vaddr); 1108 base_vlimit = round_page(segs[nsegs - 1]->p_vaddr + 1109 segs[nsegs - 1]->p_memsz); 1110 mapsize = base_vlimit - base_vaddr; 1111 1112 lf = linker_make_file(filename, &link_elf_class); 1113 if (lf == NULL) { 1114 error = ENOMEM; 1115 goto out; 1116 } 1117 1118 ef = (elf_file_t) lf; 1119 #ifdef SPARSE_MAPPING 1120 ef->object = vm_pager_allocate(OBJT_PHYS, NULL, mapsize, VM_PROT_ALL, 1121 0, thread0.td_ucred); 1122 if (ef->object == NULL) { 1123 error = ENOMEM; 1124 goto out; 1125 } 1126 #ifdef __amd64__ 1127 mapbase = (caddr_t)KERNBASE; 1128 #else 1129 mapbase = (caddr_t)vm_map_min(kernel_map); 1130 #endif 1131 /* 1132 * Mapping protections are downgraded after relocation processing. 1133 */ 1134 error = vm_map_find(kernel_map, ef->object, 0, 1135 (vm_offset_t *)&mapbase, mapsize, 0, VMFS_OPTIMAL_SPACE, 1136 VM_PROT_ALL, VM_PROT_ALL, 0); 1137 if (error != 0) { 1138 vm_object_deallocate(ef->object); 1139 ef->object = NULL; 1140 goto out; 1141 } 1142 #else 1143 mapbase = malloc_exec(mapsize, M_LINKER, M_WAITOK); 1144 #endif 1145 ef->address = mapbase; 1146 1147 /* 1148 * Read the text and data sections and zero the bss. 1149 */ 1150 for (i = 0; i < nsegs; i++) { 1151 segbase = mapbase + segs[i]->p_vaddr - base_vaddr; 1152 1153 #ifdef SPARSE_MAPPING 1154 /* 1155 * Consecutive segments may have different mapping permissions, 1156 * so be strict and verify that their mappings do not overlap. 1157 */ 1158 if (((vm_offset_t)segbase & PAGE_MASK) != 0) { 1159 error = EINVAL; 1160 goto out; 1161 } 1162 1163 error = vm_map_wire(kernel_map, 1164 (vm_offset_t)segbase, 1165 (vm_offset_t)segbase + round_page(segs[i]->p_memsz), 1166 VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES); 1167 if (error != KERN_SUCCESS) { 1168 error = ENOMEM; 1169 goto out; 1170 } 1171 #endif 1172 1173 error = vn_rdwr(UIO_READ, nd.ni_vp, 1174 segbase, segs[i]->p_filesz, segs[i]->p_offset, 1175 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1176 &resid, td); 1177 if (error != 0) 1178 goto out; 1179 bzero(segbase + segs[i]->p_filesz, 1180 segs[i]->p_memsz - segs[i]->p_filesz); 1181 } 1182 1183 #ifdef GPROF 1184 /* Update profiling information with the new text segment. */ 1185 mtx_lock(&Giant); 1186 kmupetext((uintfptr_t)(mapbase + segs[0]->p_vaddr - base_vaddr + 1187 segs[0]->p_memsz)); 1188 mtx_unlock(&Giant); 1189 #endif 1190 1191 ef->dynamic = (Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr); 1192 1193 lf->address = ef->address; 1194 lf->size = mapsize; 1195 1196 error = parse_dynamic(ef); 1197 if (error != 0) 1198 goto out; 1199 error = parse_dpcpu(ef); 1200 if (error != 0) 1201 goto out; 1202 #ifdef VIMAGE 1203 error = parse_vnet(ef); 1204 if (error != 0) 1205 goto out; 1206 #endif 1207 link_elf_reloc_local(lf); 1208 1209 VOP_UNLOCK(nd.ni_vp); 1210 error = linker_load_dependencies(lf); 1211 vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY); 1212 if (error != 0) 1213 goto out; 1214 error = relocate_file(ef); 1215 if (error != 0) 1216 goto out; 1217 1218 #ifdef SPARSE_MAPPING 1219 /* 1220 * Downgrade permissions on text segment mappings now that relocation 1221 * processing is complete. Restrict permissions on read-only segments. 1222 */ 1223 for (i = 0; i < nsegs; i++) { 1224 vm_prot_t prot; 1225 1226 if (segs[i]->p_type != PT_LOAD) 1227 continue; 1228 1229 prot = VM_PROT_READ; 1230 if ((segs[i]->p_flags & PF_W) != 0) 1231 prot |= VM_PROT_WRITE; 1232 if ((segs[i]->p_flags & PF_X) != 0) 1233 prot |= VM_PROT_EXECUTE; 1234 segbase = mapbase + segs[i]->p_vaddr - base_vaddr; 1235 error = vm_map_protect(kernel_map, 1236 (vm_offset_t)segbase, 1237 (vm_offset_t)segbase + round_page(segs[i]->p_memsz), 1238 prot, 0, VM_MAP_PROTECT_SET_PROT); 1239 if (error != KERN_SUCCESS) { 1240 error = ENOMEM; 1241 goto out; 1242 } 1243 } 1244 #endif 1245 1246 /* 1247 * Try and load the symbol table if it's present. (you can 1248 * strip it!) 1249 */ 1250 nbytes = hdr->e_shnum * hdr->e_shentsize; 1251 if (nbytes == 0 || hdr->e_shoff == 0) 1252 goto nosyms; 1253 shdr = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO); 1254 error = vn_rdwr(UIO_READ, nd.ni_vp, 1255 (caddr_t)shdr, nbytes, hdr->e_shoff, 1256 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1257 &resid, td); 1258 if (error != 0) 1259 goto out; 1260 1261 /* Read section string table */ 1262 shstrindex = hdr->e_shstrndx; 1263 if (shstrindex != 0 && shdr[shstrindex].sh_type == SHT_STRTAB && 1264 shdr[shstrindex].sh_size != 0) { 1265 nbytes = shdr[shstrindex].sh_size; 1266 shstrs = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO); 1267 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shstrs, nbytes, 1268 shdr[shstrindex].sh_offset, UIO_SYSSPACE, IO_NODELOCKED, 1269 td->td_ucred, NOCRED, &resid, td); 1270 if (error) 1271 goto out; 1272 } 1273 1274 symtabindex = -1; 1275 symstrindex = -1; 1276 for (i = 0; i < hdr->e_shnum; i++) { 1277 if (shdr[i].sh_type == SHT_SYMTAB) { 1278 symtabindex = i; 1279 symstrindex = shdr[i].sh_link; 1280 } else if (shstrs != NULL && shdr[i].sh_name != 0 && 1281 strcmp(shstrs + shdr[i].sh_name, ".ctors") == 0) { 1282 /* Record relocated address and size of .ctors. */ 1283 lf->ctors_addr = mapbase + shdr[i].sh_addr - base_vaddr; 1284 lf->ctors_size = shdr[i].sh_size; 1285 } 1286 } 1287 if (symtabindex < 0 || symstrindex < 0) 1288 goto nosyms; 1289 1290 symcnt = shdr[symtabindex].sh_size; 1291 ef->symbase = malloc(symcnt, M_LINKER, M_WAITOK); 1292 strcnt = shdr[symstrindex].sh_size; 1293 ef->strbase = malloc(strcnt, M_LINKER, M_WAITOK); 1294 1295 error = vn_rdwr(UIO_READ, nd.ni_vp, 1296 ef->symbase, symcnt, shdr[symtabindex].sh_offset, 1297 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1298 &resid, td); 1299 if (error != 0) 1300 goto out; 1301 error = vn_rdwr(UIO_READ, nd.ni_vp, 1302 ef->strbase, strcnt, shdr[symstrindex].sh_offset, 1303 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1304 &resid, td); 1305 if (error != 0) 1306 goto out; 1307 1308 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym); 1309 ef->ddbsymtab = (const Elf_Sym *)ef->symbase; 1310 ef->ddbstrcnt = strcnt; 1311 ef->ddbstrtab = ef->strbase; 1312 1313 nosyms: 1314 1315 #ifdef __arm__ 1316 link_elf_locate_exidx(lf, shdr, hdr->e_shnum); 1317 #endif 1318 1319 error = link_elf_link_common_finish(lf); 1320 if (error != 0) 1321 goto out; 1322 1323 *result = lf; 1324 1325 out: 1326 VOP_UNLOCK(nd.ni_vp); 1327 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1328 if (error != 0 && lf != NULL) 1329 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1330 free(shdr, M_LINKER); 1331 free(firstpage, M_LINKER); 1332 free(shstrs, M_LINKER); 1333 1334 return (error); 1335 } 1336 1337 Elf_Addr 1338 elf_relocaddr(linker_file_t lf, Elf_Addr x) 1339 { 1340 elf_file_t ef; 1341 1342 KASSERT(lf->ops->cls == (kobj_class_t)&link_elf_class, 1343 ("elf_relocaddr: unexpected linker file %p", lf)); 1344 1345 ef = (elf_file_t)lf; 1346 if (x >= ef->pcpu_start && x < ef->pcpu_stop) 1347 return ((x - ef->pcpu_start) + ef->pcpu_base); 1348 #ifdef VIMAGE 1349 if (x >= ef->vnet_start && x < ef->vnet_stop) 1350 return ((x - ef->vnet_start) + ef->vnet_base); 1351 #endif 1352 return (x); 1353 } 1354 1355 static void 1356 link_elf_unload_file(linker_file_t file) 1357 { 1358 elf_file_t ef = (elf_file_t) file; 1359 1360 if (ef->pcpu_base != 0) { 1361 dpcpu_free((void *)ef->pcpu_base, 1362 ef->pcpu_stop - ef->pcpu_start); 1363 elf_set_delete(&set_pcpu_list, ef->pcpu_start); 1364 } 1365 #ifdef VIMAGE 1366 if (ef->vnet_base != 0) { 1367 vnet_data_free((void *)ef->vnet_base, 1368 ef->vnet_stop - ef->vnet_start); 1369 elf_set_delete(&set_vnet_list, ef->vnet_start); 1370 } 1371 #endif 1372 #ifdef GDB 1373 if (ef->gdb.l_ld != NULL) { 1374 GDB_STATE(RT_DELETE); 1375 free((void *)(uintptr_t)ef->gdb.l_name, M_LINKER); 1376 link_elf_delete_gdb(&ef->gdb); 1377 GDB_STATE(RT_CONSISTENT); 1378 } 1379 #endif 1380 1381 /* Notify MD code that a module is being unloaded. */ 1382 elf_cpu_unload_file(file); 1383 1384 if (ef->preloaded) { 1385 link_elf_unload_preload(file); 1386 return; 1387 } 1388 1389 #ifdef SPARSE_MAPPING 1390 if (ef->object != NULL) { 1391 vm_map_remove(kernel_map, (vm_offset_t) ef->address, 1392 (vm_offset_t) ef->address 1393 + (ef->object->size << PAGE_SHIFT)); 1394 } 1395 #else 1396 free(ef->address, M_LINKER); 1397 #endif 1398 free(ef->symbase, M_LINKER); 1399 free(ef->strbase, M_LINKER); 1400 free(ef->ctftab, M_LINKER); 1401 free(ef->ctfoff, M_LINKER); 1402 free(ef->typoff, M_LINKER); 1403 } 1404 1405 static void 1406 link_elf_unload_preload(linker_file_t file) 1407 { 1408 1409 if (file->pathname != NULL) 1410 preload_delete_name(file->pathname); 1411 } 1412 1413 static const char * 1414 symbol_name(elf_file_t ef, Elf_Size r_info) 1415 { 1416 const Elf_Sym *ref; 1417 1418 if (ELF_R_SYM(r_info)) { 1419 ref = ef->symtab + ELF_R_SYM(r_info); 1420 return (ef->strtab + ref->st_name); 1421 } 1422 return (NULL); 1423 } 1424 1425 static int 1426 symbol_type(elf_file_t ef, Elf_Size r_info) 1427 { 1428 const Elf_Sym *ref; 1429 1430 if (ELF_R_SYM(r_info)) { 1431 ref = ef->symtab + ELF_R_SYM(r_info); 1432 return (ELF_ST_TYPE(ref->st_info)); 1433 } 1434 return (STT_NOTYPE); 1435 } 1436 1437 static int 1438 relocate_file1(elf_file_t ef, elf_lookup_fn lookup, elf_reloc_fn reloc, 1439 bool ifuncs) 1440 { 1441 const Elf_Rel *rel; 1442 const Elf_Rela *rela; 1443 const char *symname; 1444 1445 #define APPLY_RELOCS(iter, tbl, tblsize, type) do { \ 1446 for ((iter) = (tbl); (iter) != NULL && \ 1447 (iter) < (tbl) + (tblsize) / sizeof(*(iter)); (iter)++) { \ 1448 if ((symbol_type(ef, (iter)->r_info) == \ 1449 STT_GNU_IFUNC || \ 1450 elf_is_ifunc_reloc((iter)->r_info)) != ifuncs) \ 1451 continue; \ 1452 if (reloc(&ef->lf, (Elf_Addr)ef->address, \ 1453 (iter), (type), lookup)) { \ 1454 symname = symbol_name(ef, (iter)->r_info); \ 1455 printf("link_elf: symbol %s undefined\n", \ 1456 symname); \ 1457 return (ENOENT); \ 1458 } \ 1459 } \ 1460 } while (0) 1461 1462 APPLY_RELOCS(rel, ef->rel, ef->relsize, ELF_RELOC_REL); 1463 APPLY_RELOCS(rela, ef->rela, ef->relasize, ELF_RELOC_RELA); 1464 APPLY_RELOCS(rel, ef->pltrel, ef->pltrelsize, ELF_RELOC_REL); 1465 APPLY_RELOCS(rela, ef->pltrela, ef->pltrelasize, ELF_RELOC_RELA); 1466 1467 #undef APPLY_RELOCS 1468 1469 return (0); 1470 } 1471 1472 static int 1473 relocate_file(elf_file_t ef) 1474 { 1475 int error; 1476 1477 error = relocate_file1(ef, elf_lookup, elf_reloc, false); 1478 if (error == 0) 1479 error = relocate_file1(ef, elf_lookup, elf_reloc, true); 1480 return (error); 1481 } 1482 1483 /* 1484 * Hash function for symbol table lookup. Don't even think about changing 1485 * this. It is specified by the System V ABI. 1486 */ 1487 static unsigned long 1488 elf_hash(const char *name) 1489 { 1490 const unsigned char *p = (const unsigned char *) name; 1491 unsigned long h = 0; 1492 unsigned long g; 1493 1494 while (*p != '\0') { 1495 h = (h << 4) + *p++; 1496 if ((g = h & 0xf0000000) != 0) 1497 h ^= g >> 24; 1498 h &= ~g; 1499 } 1500 return (h); 1501 } 1502 1503 static int 1504 link_elf_lookup_symbol1(linker_file_t lf, const char *name, c_linker_sym_t *sym, 1505 bool see_local) 1506 { 1507 elf_file_t ef = (elf_file_t) lf; 1508 unsigned long symnum; 1509 const Elf_Sym* symp; 1510 const char *strp; 1511 unsigned long hash; 1512 1513 /* If we don't have a hash, bail. */ 1514 if (ef->buckets == NULL || ef->nbuckets == 0) { 1515 printf("link_elf_lookup_symbol: missing symbol hash table\n"); 1516 return (ENOENT); 1517 } 1518 1519 /* First, search hashed global symbols */ 1520 hash = elf_hash(name); 1521 symnum = ef->buckets[hash % ef->nbuckets]; 1522 1523 while (symnum != STN_UNDEF) { 1524 if (symnum >= ef->nchains) { 1525 printf("%s: corrupt symbol table\n", __func__); 1526 return (ENOENT); 1527 } 1528 1529 symp = ef->symtab + symnum; 1530 if (symp->st_name == 0) { 1531 printf("%s: corrupt symbol table\n", __func__); 1532 return (ENOENT); 1533 } 1534 1535 strp = ef->strtab + symp->st_name; 1536 1537 if (strcmp(name, strp) == 0) { 1538 if (symp->st_shndx != SHN_UNDEF || 1539 (symp->st_value != 0 && 1540 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1541 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC))) { 1542 if (see_local || 1543 ELF_ST_BIND(symp->st_info) != STB_LOCAL) { 1544 *sym = (c_linker_sym_t) symp; 1545 return (0); 1546 } 1547 } 1548 return (ENOENT); 1549 } 1550 1551 symnum = ef->chains[symnum]; 1552 } 1553 1554 return (ENOENT); 1555 } 1556 1557 static int 1558 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym) 1559 { 1560 if (link_elf_leak_locals) 1561 return (link_elf_lookup_debug_symbol(lf, name, sym)); 1562 return (link_elf_lookup_symbol1(lf, name, sym, false)); 1563 } 1564 1565 static int 1566 link_elf_lookup_debug_symbol(linker_file_t lf, const char *name, 1567 c_linker_sym_t *sym) 1568 { 1569 elf_file_t ef = (elf_file_t)lf; 1570 const Elf_Sym* symp; 1571 const char *strp; 1572 int i; 1573 1574 if (link_elf_lookup_symbol1(lf, name, sym, true) == 0) 1575 return (0); 1576 1577 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1578 strp = ef->ddbstrtab + symp->st_name; 1579 if (strcmp(name, strp) == 0) { 1580 if (symp->st_shndx != SHN_UNDEF || 1581 (symp->st_value != 0 && 1582 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1583 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC))) { 1584 *sym = (c_linker_sym_t) symp; 1585 return (0); 1586 } 1587 return (ENOENT); 1588 } 1589 } 1590 1591 return (ENOENT); 1592 } 1593 1594 static int 1595 link_elf_symbol_values1(linker_file_t lf, c_linker_sym_t sym, 1596 linker_symval_t *symval, bool see_local) 1597 { 1598 elf_file_t ef; 1599 const Elf_Sym *es; 1600 caddr_t val; 1601 1602 ef = (elf_file_t)lf; 1603 es = (const Elf_Sym *)sym; 1604 if (es >= ef->symtab && es < ef->symtab + ef->nchains) { 1605 if (!see_local && ELF_ST_BIND(es->st_info) == STB_LOCAL) 1606 return (ENOENT); 1607 symval->name = ef->strtab + es->st_name; 1608 val = (caddr_t)ef->address + es->st_value; 1609 if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC) 1610 val = ((caddr_t (*)(void))val)(); 1611 symval->value = val; 1612 symval->size = es->st_size; 1613 return (0); 1614 } 1615 return (ENOENT); 1616 } 1617 1618 static int 1619 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, 1620 linker_symval_t *symval) 1621 { 1622 if (link_elf_leak_locals) 1623 return (link_elf_debug_symbol_values(lf, sym, symval)); 1624 return (link_elf_symbol_values1(lf, sym, symval, false)); 1625 } 1626 1627 static int 1628 link_elf_debug_symbol_values(linker_file_t lf, c_linker_sym_t sym, 1629 linker_symval_t *symval) 1630 { 1631 elf_file_t ef = (elf_file_t)lf; 1632 const Elf_Sym *es = (const Elf_Sym *)sym; 1633 caddr_t val; 1634 1635 if (link_elf_symbol_values1(lf, sym, symval, true) == 0) 1636 return (0); 1637 if (ef->symtab == ef->ddbsymtab) 1638 return (ENOENT); 1639 1640 if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) { 1641 symval->name = ef->ddbstrtab + es->st_name; 1642 val = (caddr_t)ef->address + es->st_value; 1643 if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC) 1644 val = ((caddr_t (*)(void))val)(); 1645 symval->value = val; 1646 symval->size = es->st_size; 1647 return (0); 1648 } 1649 return (ENOENT); 1650 } 1651 1652 static int 1653 link_elf_search_symbol(linker_file_t lf, caddr_t value, 1654 c_linker_sym_t *sym, long *diffp) 1655 { 1656 elf_file_t ef = (elf_file_t)lf; 1657 u_long off = (uintptr_t)(void *)value; 1658 u_long diff = off; 1659 u_long st_value; 1660 const Elf_Sym *es; 1661 const Elf_Sym *best = NULL; 1662 int i; 1663 1664 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) { 1665 if (es->st_name == 0) 1666 continue; 1667 st_value = es->st_value + (uintptr_t) (void *) ef->address; 1668 if (off >= st_value) { 1669 if (off - st_value < diff) { 1670 diff = off - st_value; 1671 best = es; 1672 if (diff == 0) 1673 break; 1674 } else if (off - st_value == diff) { 1675 best = es; 1676 } 1677 } 1678 } 1679 if (best == NULL) 1680 *diffp = off; 1681 else 1682 *diffp = diff; 1683 *sym = (c_linker_sym_t) best; 1684 1685 return (0); 1686 } 1687 1688 /* 1689 * Look up a linker set on an ELF system. 1690 */ 1691 static int 1692 link_elf_lookup_set(linker_file_t lf, const char *name, 1693 void ***startp, void ***stopp, int *countp) 1694 { 1695 c_linker_sym_t sym; 1696 linker_symval_t symval; 1697 char *setsym; 1698 void **start, **stop; 1699 int len, error = 0, count; 1700 1701 len = strlen(name) + sizeof("__start_set_"); /* sizeof includes \0 */ 1702 setsym = malloc(len, M_LINKER, M_WAITOK); 1703 1704 /* get address of first entry */ 1705 snprintf(setsym, len, "%s%s", "__start_set_", name); 1706 error = link_elf_lookup_symbol(lf, setsym, &sym); 1707 if (error != 0) 1708 goto out; 1709 link_elf_symbol_values(lf, sym, &symval); 1710 if (symval.value == 0) { 1711 error = ESRCH; 1712 goto out; 1713 } 1714 start = (void **)symval.value; 1715 1716 /* get address of last entry */ 1717 snprintf(setsym, len, "%s%s", "__stop_set_", name); 1718 error = link_elf_lookup_symbol(lf, setsym, &sym); 1719 if (error != 0) 1720 goto out; 1721 link_elf_symbol_values(lf, sym, &symval); 1722 if (symval.value == 0) { 1723 error = ESRCH; 1724 goto out; 1725 } 1726 stop = (void **)symval.value; 1727 1728 /* and the number of entries */ 1729 count = stop - start; 1730 1731 /* and copy out */ 1732 if (startp != NULL) 1733 *startp = start; 1734 if (stopp != NULL) 1735 *stopp = stop; 1736 if (countp != NULL) 1737 *countp = count; 1738 1739 out: 1740 free(setsym, M_LINKER); 1741 return (error); 1742 } 1743 1744 static int 1745 link_elf_each_function_name(linker_file_t file, 1746 int (*callback)(const char *, void *), void *opaque) 1747 { 1748 elf_file_t ef = (elf_file_t)file; 1749 const Elf_Sym *symp; 1750 int i, error; 1751 1752 /* Exhaustive search */ 1753 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1754 if (symp->st_value != 0 && 1755 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1756 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) { 1757 error = callback(ef->ddbstrtab + symp->st_name, opaque); 1758 if (error != 0) 1759 return (error); 1760 } 1761 } 1762 return (0); 1763 } 1764 1765 static int 1766 link_elf_each_function_nameval(linker_file_t file, 1767 linker_function_nameval_callback_t callback, void *opaque) 1768 { 1769 linker_symval_t symval; 1770 elf_file_t ef = (elf_file_t)file; 1771 const Elf_Sym *symp; 1772 int i, error; 1773 1774 /* Exhaustive search */ 1775 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1776 if (symp->st_value != 0 && 1777 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1778 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) { 1779 error = link_elf_debug_symbol_values(file, 1780 (c_linker_sym_t) symp, &symval); 1781 if (error == 0) 1782 error = callback(file, i, &symval, opaque); 1783 if (error != 0) 1784 return (error); 1785 } 1786 } 1787 return (0); 1788 } 1789 1790 const Elf_Sym * 1791 elf_get_sym(linker_file_t lf, Elf_Size symidx) 1792 { 1793 elf_file_t ef = (elf_file_t)lf; 1794 1795 if (symidx >= ef->nchains) 1796 return (NULL); 1797 return (ef->symtab + symidx); 1798 } 1799 1800 const char * 1801 elf_get_symname(linker_file_t lf, Elf_Size symidx) 1802 { 1803 elf_file_t ef = (elf_file_t)lf; 1804 const Elf_Sym *sym; 1805 1806 if (symidx >= ef->nchains) 1807 return (NULL); 1808 sym = ef->symtab + symidx; 1809 return (ef->strtab + sym->st_name); 1810 } 1811 1812 /* 1813 * Symbol lookup function that can be used when the symbol index is known (ie 1814 * in relocations). It uses the symbol index instead of doing a fully fledged 1815 * hash table based lookup when such is valid. For example for local symbols. 1816 * This is not only more efficient, it's also more correct. It's not always 1817 * the case that the symbol can be found through the hash table. 1818 */ 1819 static int 1820 elf_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *res) 1821 { 1822 elf_file_t ef = (elf_file_t)lf; 1823 const Elf_Sym *sym; 1824 const char *symbol; 1825 Elf_Addr addr, start, base; 1826 1827 /* Don't even try to lookup the symbol if the index is bogus. */ 1828 if (symidx >= ef->nchains) { 1829 *res = 0; 1830 return (EINVAL); 1831 } 1832 1833 sym = ef->symtab + symidx; 1834 1835 /* 1836 * Don't do a full lookup when the symbol is local. It may even 1837 * fail because it may not be found through the hash table. 1838 */ 1839 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) { 1840 /* Force lookup failure when we have an insanity. */ 1841 if (sym->st_shndx == SHN_UNDEF || sym->st_value == 0) { 1842 *res = 0; 1843 return (EINVAL); 1844 } 1845 *res = ((Elf_Addr)ef->address + sym->st_value); 1846 return (0); 1847 } 1848 1849 /* 1850 * XXX we can avoid doing a hash table based lookup for global 1851 * symbols as well. This however is not always valid, so we'll 1852 * just do it the hard way for now. Performance tweaks can 1853 * always be added. 1854 */ 1855 1856 symbol = ef->strtab + sym->st_name; 1857 1858 /* Force a lookup failure if the symbol name is bogus. */ 1859 if (*symbol == 0) { 1860 *res = 0; 1861 return (EINVAL); 1862 } 1863 1864 addr = ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps)); 1865 if (addr == 0 && ELF_ST_BIND(sym->st_info) != STB_WEAK) { 1866 *res = 0; 1867 return (EINVAL); 1868 } 1869 1870 if (elf_set_find(&set_pcpu_list, addr, &start, &base)) 1871 addr = addr - start + base; 1872 #ifdef VIMAGE 1873 else if (elf_set_find(&set_vnet_list, addr, &start, &base)) 1874 addr = addr - start + base; 1875 #endif 1876 *res = addr; 1877 return (0); 1878 } 1879 1880 static void 1881 link_elf_reloc_local(linker_file_t lf) 1882 { 1883 const Elf_Rel *rellim; 1884 const Elf_Rel *rel; 1885 const Elf_Rela *relalim; 1886 const Elf_Rela *rela; 1887 elf_file_t ef = (elf_file_t)lf; 1888 1889 /* Perform relocations without addend if there are any: */ 1890 if ((rel = ef->rel) != NULL) { 1891 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize); 1892 while (rel < rellim) { 1893 elf_reloc_local(lf, (Elf_Addr)ef->address, rel, 1894 ELF_RELOC_REL, elf_lookup); 1895 rel++; 1896 } 1897 } 1898 1899 /* Perform relocations with addend if there are any: */ 1900 if ((rela = ef->rela) != NULL) { 1901 relalim = (const Elf_Rela *) 1902 ((const char *)ef->rela + ef->relasize); 1903 while (rela < relalim) { 1904 elf_reloc_local(lf, (Elf_Addr)ef->address, rela, 1905 ELF_RELOC_RELA, elf_lookup); 1906 rela++; 1907 } 1908 } 1909 } 1910 1911 static long 1912 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab) 1913 { 1914 elf_file_t ef = (elf_file_t)lf; 1915 1916 *symtab = ef->ddbsymtab; 1917 1918 if (*symtab == NULL) 1919 return (0); 1920 1921 return (ef->ddbsymcnt); 1922 } 1923 1924 static long 1925 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab) 1926 { 1927 elf_file_t ef = (elf_file_t)lf; 1928 1929 *strtab = ef->ddbstrtab; 1930 1931 if (*strtab == NULL) 1932 return (0); 1933 1934 return (ef->ddbstrcnt); 1935 } 1936 1937 #if defined(__i386__) || defined(__amd64__) || defined(__aarch64__) || defined(__powerpc__) 1938 /* 1939 * Use this lookup routine when performing relocations early during boot. 1940 * The generic lookup routine depends on kobj, which is not initialized 1941 * at that point. 1942 */ 1943 static int 1944 elf_lookup_ifunc(linker_file_t lf, Elf_Size symidx, int deps __unused, 1945 Elf_Addr *res) 1946 { 1947 elf_file_t ef; 1948 const Elf_Sym *symp; 1949 caddr_t val; 1950 1951 ef = (elf_file_t)lf; 1952 symp = ef->symtab + symidx; 1953 if (ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC) { 1954 val = (caddr_t)ef->address + symp->st_value; 1955 *res = ((Elf_Addr (*)(void))val)(); 1956 return (0); 1957 } 1958 return (ENOENT); 1959 } 1960 1961 void 1962 link_elf_ireloc(caddr_t kmdp) 1963 { 1964 struct elf_file eff; 1965 elf_file_t ef; 1966 1967 ef = &eff; 1968 1969 bzero_early(ef, sizeof(*ef)); 1970 1971 ef->modptr = kmdp; 1972 ef->dynamic = (Elf_Dyn *)&_DYNAMIC; 1973 1974 #ifdef RELOCATABLE_KERNEL 1975 ef->address = (caddr_t) (__startkernel - KERNBASE); 1976 #else 1977 ef->address = 0; 1978 #endif 1979 parse_dynamic(ef); 1980 1981 link_elf_preload_parse_symbols(ef); 1982 relocate_file1(ef, elf_lookup_ifunc, elf_reloc, true); 1983 } 1984 1985 #if defined(__aarch64__) || defined(__amd64__) 1986 void 1987 link_elf_late_ireloc(void) 1988 { 1989 elf_file_t ef; 1990 1991 KASSERT(linker_kernel_file != NULL, 1992 ("link_elf_late_ireloc: No kernel linker file found")); 1993 ef = (elf_file_t)linker_kernel_file; 1994 1995 relocate_file1(ef, elf_lookup_ifunc, elf_reloc_late, true); 1996 } 1997 #endif 1998 #endif
Cache object: 3df29342d507b4edd766cfc050bbeec1
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