1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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 "opt_ddb.h" 30 #include "opt_gdb.h" 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/kernel.h> 35 #include <sys/lock.h> 36 #include <sys/malloc.h> 37 #ifdef SPARSE_MAPPING 38 #include <sys/mman.h> 39 #endif 40 #include <sys/mutex.h> 41 #include <sys/mount.h> 42 #include <sys/pcpu.h> 43 #include <sys/proc.h> 44 #include <sys/namei.h> 45 #include <sys/fcntl.h> 46 #include <sys/vnode.h> 47 #include <sys/linker.h> 48 #include <sys/sysctl.h> 49 #include <sys/tslog.h> 50 51 #include <machine/elf.h> 52 53 #include <net/vnet.h> 54 55 #include <security/mac/mac_framework.h> 56 57 #include <vm/vm.h> 58 #include <vm/vm_param.h> 59 #ifdef SPARSE_MAPPING 60 #include <vm/vm_object.h> 61 #include <vm/vm_kern.h> 62 #include <vm/vm_extern.h> 63 #endif 64 #include <vm/pmap.h> 65 #include <vm/vm_map.h> 66 67 #include <sys/link_elf.h> 68 69 #include "linker_if.h" 70 71 #ifdef DDB_CTF 72 #include <ddb/db_ctf.h> 73 #endif 74 75 #define MAXSEGS 4 76 77 typedef struct elf_file { 78 struct linker_file lf; /* Common fields */ 79 int preloaded; /* Was file pre-loaded */ 80 caddr_t address; /* Relocation address */ 81 #ifdef SPARSE_MAPPING 82 vm_object_t object; /* VM object to hold file pages */ 83 #endif 84 Elf_Dyn *dynamic; /* Symbol table etc. */ 85 Elf_Hashelt nbuckets; /* DT_HASH info */ 86 Elf_Hashelt nchains; 87 const Elf_Hashelt *buckets; 88 const Elf_Hashelt *chains; 89 caddr_t hash; 90 caddr_t strtab; /* DT_STRTAB */ 91 int strsz; /* DT_STRSZ */ 92 const Elf_Sym *symtab; /* DT_SYMTAB */ 93 Elf_Addr *got; /* DT_PLTGOT */ 94 const Elf_Rel *pltrel; /* DT_JMPREL */ 95 int pltrelsize; /* DT_PLTRELSZ */ 96 const Elf_Rela *pltrela; /* DT_JMPREL */ 97 int pltrelasize; /* DT_PLTRELSZ */ 98 const Elf_Rel *rel; /* DT_REL */ 99 int relsize; /* DT_RELSZ */ 100 const Elf_Rela *rela; /* DT_RELA */ 101 int relasize; /* DT_RELASZ */ 102 caddr_t modptr; 103 const Elf_Sym *ddbsymtab; /* The symbol table we are using */ 104 long ddbsymcnt; /* Number of symbols */ 105 caddr_t ddbstrtab; /* String table */ 106 long ddbstrcnt; /* number of bytes in string table */ 107 caddr_t symbase; /* malloc'ed symbold base */ 108 caddr_t strbase; /* malloc'ed string base */ 109 caddr_t ctftab; /* CTF table */ 110 long ctfcnt; /* number of bytes in CTF table */ 111 caddr_t ctfoff; /* CTF offset table */ 112 caddr_t typoff; /* Type offset table */ 113 long typlen; /* Number of type entries. */ 114 Elf_Addr pcpu_start; /* Pre-relocation pcpu set start. */ 115 Elf_Addr pcpu_stop; /* Pre-relocation pcpu set stop. */ 116 Elf_Addr pcpu_base; /* Relocated pcpu set address. */ 117 #ifdef VIMAGE 118 Elf_Addr vnet_start; /* Pre-relocation vnet set start. */ 119 Elf_Addr vnet_stop; /* Pre-relocation vnet set stop. */ 120 Elf_Addr vnet_base; /* Relocated vnet set address. */ 121 #endif 122 #ifdef GDB 123 struct link_map gdb; /* hooks for gdb */ 124 #endif 125 } *elf_file_t; 126 127 struct elf_set { 128 Elf_Addr es_start; 129 Elf_Addr es_stop; 130 Elf_Addr es_base; 131 TAILQ_ENTRY(elf_set) es_link; 132 }; 133 134 TAILQ_HEAD(elf_set_head, elf_set); 135 136 #include <kern/kern_ctf.c> 137 138 static int link_elf_link_common_finish(linker_file_t); 139 static int link_elf_link_preload(linker_class_t cls, 140 const char *, linker_file_t *); 141 static int link_elf_link_preload_finish(linker_file_t); 142 static int link_elf_load_file(linker_class_t, const char *, 143 linker_file_t *); 144 static int link_elf_lookup_symbol(linker_file_t, const char *, 145 c_linker_sym_t *); 146 static int link_elf_lookup_debug_symbol(linker_file_t, const char *, 147 c_linker_sym_t *); 148 static int link_elf_lookup_debug_symbol_ctf(linker_file_t lf, 149 const char *name, c_linker_sym_t *sym, linker_ctf_t *lc); 150 static int link_elf_symbol_values(linker_file_t, c_linker_sym_t, 151 linker_symval_t *); 152 static int link_elf_debug_symbol_values(linker_file_t, c_linker_sym_t, 153 linker_symval_t*); 154 static int link_elf_search_symbol(linker_file_t, caddr_t, 155 c_linker_sym_t *, long *); 156 157 static void link_elf_unload_file(linker_file_t); 158 static void link_elf_unload_preload(linker_file_t); 159 static int link_elf_lookup_set(linker_file_t, const char *, 160 void ***, void ***, int *); 161 static int link_elf_each_function_name(linker_file_t, 162 int (*)(const char *, void *), void *); 163 static int link_elf_each_function_nameval(linker_file_t, 164 linker_function_nameval_callback_t, void *); 165 static void link_elf_reloc_local(linker_file_t); 166 static long link_elf_symtab_get(linker_file_t, const Elf_Sym **); 167 static long link_elf_strtab_get(linker_file_t, caddr_t *); 168 #ifdef VIMAGE 169 static void link_elf_propagate_vnets(linker_file_t); 170 #endif 171 static int elf_lookup(linker_file_t, Elf_Size, int, Elf_Addr *); 172 173 static kobj_method_t link_elf_methods[] = { 174 KOBJMETHOD(linker_lookup_symbol, link_elf_lookup_symbol), 175 KOBJMETHOD(linker_lookup_debug_symbol, link_elf_lookup_debug_symbol), 176 KOBJMETHOD(linker_lookup_debug_symbol_ctf, link_elf_lookup_debug_symbol_ctf), 177 KOBJMETHOD(linker_symbol_values, link_elf_symbol_values), 178 KOBJMETHOD(linker_debug_symbol_values, link_elf_debug_symbol_values), 179 KOBJMETHOD(linker_search_symbol, link_elf_search_symbol), 180 KOBJMETHOD(linker_unload, link_elf_unload_file), 181 KOBJMETHOD(linker_load_file, link_elf_load_file), 182 KOBJMETHOD(linker_link_preload, link_elf_link_preload), 183 KOBJMETHOD(linker_link_preload_finish, link_elf_link_preload_finish), 184 KOBJMETHOD(linker_lookup_set, link_elf_lookup_set), 185 KOBJMETHOD(linker_each_function_name, link_elf_each_function_name), 186 KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval), 187 KOBJMETHOD(linker_ctf_get, link_elf_ctf_get), 188 KOBJMETHOD(linker_ctf_lookup_typename, link_elf_ctf_lookup_typename), 189 KOBJMETHOD(linker_symtab_get, link_elf_symtab_get), 190 KOBJMETHOD(linker_strtab_get, link_elf_strtab_get), 191 #ifdef VIMAGE 192 KOBJMETHOD(linker_propagate_vnets, link_elf_propagate_vnets), 193 #endif 194 KOBJMETHOD_END 195 }; 196 197 static struct linker_class link_elf_class = { 198 #if ELF_TARG_CLASS == ELFCLASS32 199 "elf32", 200 #else 201 "elf64", 202 #endif 203 link_elf_methods, sizeof(struct elf_file) 204 }; 205 206 static bool link_elf_leak_locals = true; 207 SYSCTL_BOOL(_debug, OID_AUTO, link_elf_leak_locals, 208 CTLFLAG_RWTUN, &link_elf_leak_locals, 0, 209 "Allow local symbols to participate in global module symbol resolution"); 210 211 typedef int (*elf_reloc_fn)(linker_file_t lf, Elf_Addr relocbase, 212 const void *data, int type, elf_lookup_fn lookup); 213 214 static int parse_dynamic(elf_file_t); 215 static int relocate_file(elf_file_t); 216 static int relocate_file1(elf_file_t ef, elf_lookup_fn lookup, 217 elf_reloc_fn reloc, bool ifuncs); 218 static int link_elf_preload_parse_symbols(elf_file_t); 219 220 static struct elf_set_head set_pcpu_list; 221 #ifdef VIMAGE 222 static struct elf_set_head set_vnet_list; 223 #endif 224 225 static void 226 elf_set_add(struct elf_set_head *list, Elf_Addr start, Elf_Addr stop, Elf_Addr base) 227 { 228 struct elf_set *set, *iter; 229 230 set = malloc(sizeof(*set), M_LINKER, M_WAITOK); 231 set->es_start = start; 232 set->es_stop = stop; 233 set->es_base = base; 234 235 TAILQ_FOREACH(iter, list, es_link) { 236 KASSERT((set->es_start < iter->es_start && set->es_stop < iter->es_stop) || 237 (set->es_start > iter->es_start && set->es_stop > iter->es_stop), 238 ("linker sets intersection: to insert: 0x%jx-0x%jx; inserted: 0x%jx-0x%jx", 239 (uintmax_t)set->es_start, (uintmax_t)set->es_stop, 240 (uintmax_t)iter->es_start, (uintmax_t)iter->es_stop)); 241 242 if (iter->es_start > set->es_start) { 243 TAILQ_INSERT_BEFORE(iter, set, es_link); 244 break; 245 } 246 } 247 248 if (iter == NULL) 249 TAILQ_INSERT_TAIL(list, set, es_link); 250 } 251 252 static int 253 elf_set_find(struct elf_set_head *list, Elf_Addr addr, Elf_Addr *start, Elf_Addr *base) 254 { 255 struct elf_set *set; 256 257 TAILQ_FOREACH(set, list, es_link) { 258 if (addr < set->es_start) 259 return (0); 260 if (addr < set->es_stop) { 261 *start = set->es_start; 262 *base = set->es_base; 263 return (1); 264 } 265 } 266 267 return (0); 268 } 269 270 static void 271 elf_set_delete(struct elf_set_head *list, Elf_Addr start) 272 { 273 struct elf_set *set; 274 275 TAILQ_FOREACH(set, list, es_link) { 276 if (start < set->es_start) 277 break; 278 if (start == set->es_start) { 279 TAILQ_REMOVE(list, set, es_link); 280 free(set, M_LINKER); 281 return; 282 } 283 } 284 KASSERT(0, ("deleting unknown linker set (start = 0x%jx)", 285 (uintmax_t)start)); 286 } 287 288 #ifdef GDB 289 static void r_debug_state(struct r_debug *, struct link_map *); 290 291 /* 292 * A list of loaded modules for GDB to use for loading symbols. 293 */ 294 struct r_debug r_debug; 295 296 #define GDB_STATE(s) do { \ 297 r_debug.r_state = s; r_debug_state(NULL, NULL); \ 298 } while (0) 299 300 /* 301 * Function for the debugger to set a breakpoint on to gain control. 302 */ 303 static void 304 r_debug_state(struct r_debug *dummy_one __unused, 305 struct link_map *dummy_two __unused) 306 { 307 } 308 309 static void 310 link_elf_add_gdb(struct link_map *l) 311 { 312 struct link_map *prev; 313 314 l->l_next = NULL; 315 316 if (r_debug.r_map == NULL) { 317 /* Add first. */ 318 l->l_prev = NULL; 319 r_debug.r_map = l; 320 } else { 321 /* Append to list. */ 322 for (prev = r_debug.r_map; 323 prev->l_next != NULL; 324 prev = prev->l_next) 325 ; 326 l->l_prev = prev; 327 prev->l_next = l; 328 } 329 } 330 331 static void 332 link_elf_delete_gdb(struct link_map *l) 333 { 334 if (l->l_prev == NULL) { 335 /* Remove first. */ 336 if ((r_debug.r_map = l->l_next) != NULL) 337 l->l_next->l_prev = NULL; 338 } else { 339 /* Remove any but first. */ 340 if ((l->l_prev->l_next = l->l_next) != NULL) 341 l->l_next->l_prev = l->l_prev; 342 } 343 } 344 #endif /* GDB */ 345 346 /* 347 * The kernel symbol table starts here. 348 */ 349 extern struct _dynamic _DYNAMIC; 350 351 static void 352 link_elf_error(const char *filename, const char *s) 353 { 354 if (filename == NULL) 355 printf("kldload: %s\n", s); 356 else 357 printf("kldload: %s: %s\n", filename, s); 358 } 359 360 static void 361 link_elf_invoke_cbs(caddr_t addr, size_t size) 362 { 363 void (**ctor)(void); 364 size_t i, cnt; 365 366 if (addr == NULL || size == 0) 367 return; 368 cnt = size / sizeof(*ctor); 369 ctor = (void *)addr; 370 for (i = 0; i < cnt; i++) { 371 if (ctor[i] != NULL) 372 (*ctor[i])(); 373 } 374 } 375 376 static void 377 link_elf_invoke_ctors(linker_file_t lf) 378 { 379 KASSERT(lf->ctors_invoked == LF_NONE, 380 ("%s: file %s ctor state %d", 381 __func__, lf->filename, lf->ctors_invoked)); 382 383 link_elf_invoke_cbs(lf->ctors_addr, lf->ctors_size); 384 lf->ctors_invoked = LF_CTORS; 385 } 386 387 /* 388 * Actions performed after linking/loading both the preloaded kernel and any 389 * modules; whether preloaded or dynamicly loaded. 390 */ 391 static int 392 link_elf_link_common_finish(linker_file_t lf) 393 { 394 #ifdef GDB 395 elf_file_t ef = (elf_file_t)lf; 396 char *newfilename; 397 #endif 398 int error; 399 400 /* Notify MD code that a module is being loaded. */ 401 error = elf_cpu_load_file(lf); 402 if (error != 0) 403 return (error); 404 405 #ifdef GDB 406 GDB_STATE(RT_ADD); 407 ef->gdb.l_addr = lf->address; 408 newfilename = malloc(strlen(lf->filename) + 1, M_LINKER, M_WAITOK); 409 strcpy(newfilename, lf->filename); 410 ef->gdb.l_name = newfilename; 411 ef->gdb.l_ld = ef->dynamic; 412 link_elf_add_gdb(&ef->gdb); 413 GDB_STATE(RT_CONSISTENT); 414 #endif 415 416 /* Invoke .ctors */ 417 link_elf_invoke_ctors(lf); 418 return (0); 419 } 420 421 #ifdef RELOCATABLE_KERNEL 422 /* 423 * __startkernel and __endkernel are symbols set up as relocation canaries. 424 * 425 * They are defined in locore to reference linker script symbols at the 426 * beginning and end of the LOAD area. This has the desired side effect of 427 * giving us variables that have relative relocations pointing at them, so 428 * relocation of the kernel object will cause the variables to be updated 429 * automatically by the runtime linker when we initialize. 430 * 431 * There are two main reasons to relocate the kernel: 432 * 1) If the loader needed to load the kernel at an alternate load address. 433 * 2) If the kernel is switching address spaces on machines like POWER9 434 * under Radix where the high bits of the effective address are used to 435 * differentiate between hypervisor, host, guest, and problem state. 436 */ 437 extern vm_offset_t __startkernel, __endkernel; 438 #endif 439 440 static unsigned long kern_relbase = KERNBASE; 441 442 SYSCTL_ULONG(_kern, OID_AUTO, base_address, CTLFLAG_RD, 443 SYSCTL_NULL_ULONG_PTR, KERNBASE, "Kernel base address"); 444 SYSCTL_ULONG(_kern, OID_AUTO, relbase_address, CTLFLAG_RD, 445 &kern_relbase, 0, "Kernel relocated base address"); 446 447 static void 448 link_elf_init(void* arg) 449 { 450 Elf_Dyn *dp; 451 Elf_Addr *ctors_addrp; 452 Elf_Size *ctors_sizep; 453 caddr_t baseptr, sizeptr; 454 elf_file_t ef; 455 const char *modname; 456 457 linker_add_class(&link_elf_class); 458 459 dp = (Elf_Dyn *)&_DYNAMIC; 460 modname = (char *)preload_search_info(preload_kmdp, MODINFO_NAME); 461 if (modname == NULL) 462 modname = "kernel"; 463 linker_kernel_file = linker_make_file(modname, &link_elf_class); 464 if (linker_kernel_file == NULL) 465 panic("%s: Can't create linker structures for kernel", 466 __func__); 467 468 ef = (elf_file_t) linker_kernel_file; 469 ef->preloaded = 1; 470 #ifdef RELOCATABLE_KERNEL 471 /* Compute relative displacement */ 472 ef->address = (caddr_t) (__startkernel - KERNBASE); 473 #else 474 ef->address = 0; 475 #endif 476 #ifdef SPARSE_MAPPING 477 ef->object = NULL; 478 #endif 479 ef->dynamic = dp; 480 481 if (dp != NULL) 482 parse_dynamic(ef); 483 #ifdef RELOCATABLE_KERNEL 484 linker_kernel_file->address = (caddr_t)__startkernel; 485 linker_kernel_file->size = (intptr_t)(__endkernel - __startkernel); 486 kern_relbase = (unsigned long)__startkernel; 487 #else 488 linker_kernel_file->address += KERNBASE; 489 linker_kernel_file->size = -(intptr_t)linker_kernel_file->address; 490 #endif 491 492 if (preload_kmdp != NULL) { 493 ef->modptr = preload_kmdp; 494 baseptr = preload_search_info(preload_kmdp, MODINFO_ADDR); 495 if (baseptr != NULL) 496 linker_kernel_file->address = *(caddr_t *)baseptr; 497 sizeptr = preload_search_info(preload_kmdp, MODINFO_SIZE); 498 if (sizeptr != NULL) 499 linker_kernel_file->size = *(size_t *)sizeptr; 500 ctors_addrp = (Elf_Addr *)preload_search_info(preload_kmdp, 501 MODINFO_METADATA | MODINFOMD_CTORS_ADDR); 502 ctors_sizep = (Elf_Size *)preload_search_info(preload_kmdp, 503 MODINFO_METADATA | MODINFOMD_CTORS_SIZE); 504 if (ctors_addrp != NULL && ctors_sizep != NULL) { 505 linker_kernel_file->ctors_addr = ef->address + 506 *ctors_addrp; 507 linker_kernel_file->ctors_size = *ctors_sizep; 508 } 509 } 510 (void)link_elf_preload_parse_symbols(ef); 511 512 #ifdef GDB 513 r_debug.r_map = NULL; 514 r_debug.r_brk = r_debug_state; 515 r_debug.r_state = RT_CONSISTENT; 516 #endif 517 518 (void)link_elf_link_common_finish(linker_kernel_file); 519 linker_kernel_file->flags |= LINKER_FILE_LINKED; 520 TAILQ_INIT(&set_pcpu_list); 521 #ifdef VIMAGE 522 TAILQ_INIT(&set_vnet_list); 523 vnet_save_init((void *)VNET_START, VNET_STOP - VNET_START); 524 #endif 525 } 526 527 SYSINIT(link_elf, SI_SUB_KLD, SI_ORDER_THIRD, link_elf_init, NULL); 528 529 static int 530 link_elf_preload_parse_symbols(elf_file_t ef) 531 { 532 caddr_t pointer; 533 caddr_t ssym, esym, base; 534 caddr_t strtab; 535 int strcnt; 536 Elf_Sym *symtab; 537 int symcnt; 538 539 if (ef->modptr == NULL) 540 return (0); 541 pointer = preload_search_info(ef->modptr, 542 MODINFO_METADATA | MODINFOMD_SSYM); 543 if (pointer == NULL) 544 return (0); 545 ssym = *(caddr_t *)pointer; 546 pointer = preload_search_info(ef->modptr, 547 MODINFO_METADATA | MODINFOMD_ESYM); 548 if (pointer == NULL) 549 return (0); 550 esym = *(caddr_t *)pointer; 551 552 base = ssym; 553 554 symcnt = *(long *)base; 555 base += sizeof(long); 556 symtab = (Elf_Sym *)base; 557 base += roundup(symcnt, sizeof(long)); 558 559 if (base > esym || base < ssym) { 560 printf("Symbols are corrupt!\n"); 561 return (EINVAL); 562 } 563 564 strcnt = *(long *)base; 565 base += sizeof(long); 566 strtab = base; 567 base += roundup(strcnt, sizeof(long)); 568 569 if (base > esym || base < ssym) { 570 printf("Symbols are corrupt!\n"); 571 return (EINVAL); 572 } 573 574 ef->ddbsymtab = symtab; 575 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym); 576 ef->ddbstrtab = strtab; 577 ef->ddbstrcnt = strcnt; 578 579 return (0); 580 } 581 582 static int 583 parse_dynamic(elf_file_t ef) 584 { 585 Elf_Dyn *dp; 586 int plttype = DT_REL; 587 588 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) { 589 switch (dp->d_tag) { 590 case DT_HASH: 591 { 592 /* From src/libexec/rtld-elf/rtld.c */ 593 const Elf_Hashelt *hashtab = (const Elf_Hashelt *) 594 (ef->address + dp->d_un.d_ptr); 595 ef->nbuckets = hashtab[0]; 596 ef->nchains = hashtab[1]; 597 ef->buckets = hashtab + 2; 598 ef->chains = ef->buckets + ef->nbuckets; 599 break; 600 } 601 case DT_STRTAB: 602 ef->strtab = (caddr_t) (ef->address + dp->d_un.d_ptr); 603 break; 604 case DT_STRSZ: 605 ef->strsz = dp->d_un.d_val; 606 break; 607 case DT_SYMTAB: 608 ef->symtab = (Elf_Sym*) (ef->address + dp->d_un.d_ptr); 609 break; 610 case DT_SYMENT: 611 if (dp->d_un.d_val != sizeof(Elf_Sym)) 612 return (ENOEXEC); 613 break; 614 case DT_PLTGOT: 615 ef->got = (Elf_Addr *) (ef->address + dp->d_un.d_ptr); 616 break; 617 case DT_REL: 618 ef->rel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr); 619 break; 620 case DT_RELSZ: 621 ef->relsize = dp->d_un.d_val; 622 break; 623 case DT_RELENT: 624 if (dp->d_un.d_val != sizeof(Elf_Rel)) 625 return (ENOEXEC); 626 break; 627 case DT_JMPREL: 628 ef->pltrel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr); 629 break; 630 case DT_PLTRELSZ: 631 ef->pltrelsize = dp->d_un.d_val; 632 break; 633 case DT_RELA: 634 ef->rela = (const Elf_Rela *) (ef->address + dp->d_un.d_ptr); 635 break; 636 case DT_RELASZ: 637 ef->relasize = dp->d_un.d_val; 638 break; 639 case DT_RELAENT: 640 if (dp->d_un.d_val != sizeof(Elf_Rela)) 641 return (ENOEXEC); 642 break; 643 case DT_PLTREL: 644 plttype = dp->d_un.d_val; 645 if (plttype != DT_REL && plttype != DT_RELA) 646 return (ENOEXEC); 647 break; 648 #ifdef GDB 649 case DT_DEBUG: 650 dp->d_un.d_ptr = (Elf_Addr)&r_debug; 651 break; 652 #endif 653 } 654 } 655 656 if (plttype == DT_RELA) { 657 ef->pltrela = (const Elf_Rela *)ef->pltrel; 658 ef->pltrel = NULL; 659 ef->pltrelasize = ef->pltrelsize; 660 ef->pltrelsize = 0; 661 } 662 663 ef->ddbsymtab = ef->symtab; 664 ef->ddbsymcnt = ef->nchains; 665 ef->ddbstrtab = ef->strtab; 666 ef->ddbstrcnt = ef->strsz; 667 668 return elf_cpu_parse_dynamic(ef->address, ef->dynamic); 669 } 670 671 #define LS_PADDING 0x90909090 672 static int 673 parse_dpcpu(elf_file_t ef) 674 { 675 int error, size; 676 #if defined(__i386__) 677 uint32_t pad; 678 #endif 679 680 ef->pcpu_start = 0; 681 ef->pcpu_stop = 0; 682 error = link_elf_lookup_set(&ef->lf, "pcpu", (void ***)&ef->pcpu_start, 683 (void ***)&ef->pcpu_stop, NULL); 684 /* Error just means there is no pcpu set to relocate. */ 685 if (error != 0) 686 return (0); 687 size = (uintptr_t)ef->pcpu_stop - (uintptr_t)ef->pcpu_start; 688 /* Empty set? */ 689 if (size < 1) 690 return (0); 691 #if defined(__i386__) 692 /* In case we do find __start/stop_set_ symbols double-check. */ 693 if (size < 4) { 694 uprintf("Kernel module '%s' must be recompiled with " 695 "linker script\n", ef->lf.pathname); 696 return (ENOEXEC); 697 } 698 699 /* Padding from linker-script correct? */ 700 pad = *(uint32_t *)((uintptr_t)ef->pcpu_stop - sizeof(pad)); 701 if (pad != LS_PADDING) { 702 uprintf("Kernel module '%s' must be recompiled with " 703 "linker script, invalid padding %#04x (%#04x)\n", 704 ef->lf.pathname, pad, LS_PADDING); 705 return (ENOEXEC); 706 } 707 /* If we only have valid padding, nothing to do. */ 708 if (size == 4) 709 return (0); 710 #endif 711 /* 712 * Allocate space in the primary pcpu area. Copy in our 713 * initialization from the data section and then initialize 714 * all per-cpu storage from that. 715 */ 716 ef->pcpu_base = (Elf_Addr)(uintptr_t)dpcpu_alloc(size); 717 if (ef->pcpu_base == 0) { 718 printf("%s: pcpu module space is out of space; " 719 "cannot allocate %d for %s\n", 720 __func__, size, ef->lf.pathname); 721 return (ENOSPC); 722 } 723 memcpy((void *)ef->pcpu_base, (void *)ef->pcpu_start, size); 724 dpcpu_copy((void *)ef->pcpu_base, size); 725 elf_set_add(&set_pcpu_list, ef->pcpu_start, ef->pcpu_stop, 726 ef->pcpu_base); 727 728 return (0); 729 } 730 731 #ifdef VIMAGE 732 static int 733 parse_vnet(elf_file_t ef) 734 { 735 int error, size; 736 #if defined(__i386__) 737 uint32_t pad; 738 #endif 739 740 ef->vnet_start = 0; 741 ef->vnet_stop = 0; 742 ef->vnet_base = 0; 743 error = link_elf_lookup_set(&ef->lf, "vnet", (void ***)&ef->vnet_start, 744 (void ***)&ef->vnet_stop, NULL); 745 /* Error just means there is no vnet data set to relocate. */ 746 if (error != 0) 747 return (0); 748 size = (uintptr_t)ef->vnet_stop - (uintptr_t)ef->vnet_start; 749 /* Empty set? */ 750 if (size < 1) 751 return (0); 752 #if defined(__i386__) 753 /* In case we do find __start/stop_set_ symbols double-check. */ 754 if (size < 4) { 755 uprintf("Kernel module '%s' must be recompiled with " 756 "linker script\n", ef->lf.pathname); 757 return (ENOEXEC); 758 } 759 760 /* Padding from linker-script correct? */ 761 pad = *(uint32_t *)((uintptr_t)ef->vnet_stop - sizeof(pad)); 762 if (pad != LS_PADDING) { 763 uprintf("Kernel module '%s' must be recompiled with " 764 "linker script, invalid padding %#04x (%#04x)\n", 765 ef->lf.pathname, pad, LS_PADDING); 766 return (ENOEXEC); 767 } 768 /* If we only have valid padding, nothing to do. */ 769 if (size == 4) 770 return (0); 771 #endif 772 /* 773 * Allocate space in the primary vnet area. Copy in our 774 * initialization from the data section and then initialize 775 * all per-vnet storage from that. 776 */ 777 ef->vnet_base = (Elf_Addr)(uintptr_t)vnet_data_alloc(size); 778 if (ef->vnet_base == 0) { 779 printf("%s: vnet module space is out of space; " 780 "cannot allocate %d for %s\n", 781 __func__, size, ef->lf.pathname); 782 return (ENOSPC); 783 } 784 memcpy((void *)ef->vnet_base, (void *)ef->vnet_start, size); 785 vnet_save_init((void *)ef->vnet_base, size); 786 elf_set_add(&set_vnet_list, ef->vnet_start, ef->vnet_stop, 787 ef->vnet_base); 788 789 return (0); 790 } 791 #endif 792 #undef LS_PADDING 793 794 /* 795 * Apply the specified protection to the loadable segments of a preloaded linker 796 * file. 797 */ 798 static int 799 preload_protect(elf_file_t ef, vm_prot_t prot) 800 { 801 #if defined(__aarch64__) || defined(__amd64__) 802 Elf_Ehdr *hdr; 803 Elf_Phdr *phdr, *phlimit; 804 vm_prot_t nprot; 805 int error; 806 807 error = 0; 808 hdr = (Elf_Ehdr *)ef->address; 809 phdr = (Elf_Phdr *)(ef->address + hdr->e_phoff); 810 phlimit = phdr + hdr->e_phnum; 811 for (; phdr < phlimit; phdr++) { 812 if (phdr->p_type != PT_LOAD) 813 continue; 814 815 nprot = prot | VM_PROT_READ; 816 if ((phdr->p_flags & PF_W) != 0) 817 nprot |= VM_PROT_WRITE; 818 if ((phdr->p_flags & PF_X) != 0) 819 nprot |= VM_PROT_EXECUTE; 820 error = pmap_change_prot((vm_offset_t)ef->address + 821 phdr->p_vaddr, round_page(phdr->p_memsz), nprot); 822 if (error != 0) 823 break; 824 } 825 return (error); 826 #else 827 return (0); 828 #endif 829 } 830 831 #ifdef __arm__ 832 /* 833 * Locate the ARM exception/unwind table info for DDB and stack(9) use by 834 * searching for the section header that describes it. There may be no unwind 835 * info, for example in a module containing only data. 836 */ 837 static void 838 link_elf_locate_exidx(linker_file_t lf, Elf_Shdr *shdr, int nhdr) 839 { 840 int i; 841 842 for (i = 0; i < nhdr; i++) { 843 if (shdr[i].sh_type == SHT_ARM_EXIDX) { 844 lf->exidx_addr = shdr[i].sh_addr + lf->address; 845 lf->exidx_size = shdr[i].sh_size; 846 break; 847 } 848 } 849 } 850 851 /* 852 * Locate the section headers metadata in a preloaded module, then use it to 853 * locate the exception/unwind table in the module. The size of the metadata 854 * block is stored in a uint32 word immediately before the data itself, and a 855 * comment in preload_search_info() says it is safe to rely on that. 856 */ 857 static void 858 link_elf_locate_exidx_preload(struct linker_file *lf, caddr_t modptr) 859 { 860 uint32_t *modinfo; 861 Elf_Shdr *shdr; 862 uint32_t nhdr; 863 864 modinfo = (uint32_t *)preload_search_info(modptr, 865 MODINFO_METADATA | MODINFOMD_SHDR); 866 if (modinfo != NULL) { 867 shdr = (Elf_Shdr *)modinfo; 868 nhdr = modinfo[-1] / sizeof(Elf_Shdr); 869 link_elf_locate_exidx(lf, shdr, nhdr); 870 } 871 } 872 873 #endif /* __arm__ */ 874 875 static int 876 link_elf_link_preload(linker_class_t cls, const char *filename, 877 linker_file_t *result) 878 { 879 Elf_Addr *ctors_addrp; 880 Elf_Size *ctors_sizep; 881 caddr_t modptr, baseptr, sizeptr, dynptr; 882 char *type; 883 elf_file_t ef; 884 linker_file_t lf; 885 int error; 886 vm_offset_t dp; 887 888 /* Look to see if we have the file preloaded */ 889 modptr = preload_search_by_name(filename); 890 if (modptr == NULL) 891 return (ENOENT); 892 893 type = (char *)preload_search_info(modptr, MODINFO_TYPE); 894 baseptr = preload_search_info(modptr, MODINFO_ADDR); 895 sizeptr = preload_search_info(modptr, MODINFO_SIZE); 896 dynptr = preload_search_info(modptr, 897 MODINFO_METADATA | MODINFOMD_DYNAMIC); 898 if (type == NULL || strcmp(type, preload_modtype) != 0) 899 return (EFTYPE); 900 if (baseptr == NULL || sizeptr == NULL || dynptr == NULL) 901 return (EINVAL); 902 903 lf = linker_make_file(filename, &link_elf_class); 904 if (lf == NULL) 905 return (ENOMEM); 906 907 ef = (elf_file_t) lf; 908 ef->preloaded = 1; 909 ef->modptr = modptr; 910 ef->address = *(caddr_t *)baseptr; 911 #ifdef SPARSE_MAPPING 912 ef->object = NULL; 913 #endif 914 dp = (vm_offset_t)ef->address + *(vm_offset_t *)dynptr; 915 ef->dynamic = (Elf_Dyn *)dp; 916 lf->address = ef->address; 917 lf->size = *(size_t *)sizeptr; 918 919 ctors_addrp = (Elf_Addr *)preload_search_info(modptr, 920 MODINFO_METADATA | MODINFOMD_CTORS_ADDR); 921 ctors_sizep = (Elf_Size *)preload_search_info(modptr, 922 MODINFO_METADATA | MODINFOMD_CTORS_SIZE); 923 if (ctors_addrp != NULL && ctors_sizep != NULL) { 924 lf->ctors_addr = ef->address + *ctors_addrp; 925 lf->ctors_size = *ctors_sizep; 926 } 927 928 #ifdef __arm__ 929 link_elf_locate_exidx_preload(lf, modptr); 930 #endif 931 932 error = parse_dynamic(ef); 933 if (error == 0) 934 error = parse_dpcpu(ef); 935 #ifdef VIMAGE 936 if (error == 0) 937 error = parse_vnet(ef); 938 #endif 939 if (error == 0) 940 error = preload_protect(ef, VM_PROT_ALL); 941 if (error != 0) { 942 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 943 return (error); 944 } 945 link_elf_reloc_local(lf); 946 *result = lf; 947 return (0); 948 } 949 950 static int 951 link_elf_link_preload_finish(linker_file_t lf) 952 { 953 elf_file_t ef; 954 int error; 955 956 ef = (elf_file_t) lf; 957 error = relocate_file(ef); 958 if (error == 0) 959 error = preload_protect(ef, VM_PROT_NONE); 960 if (error != 0) 961 return (error); 962 (void)link_elf_preload_parse_symbols(ef); 963 964 return (link_elf_link_common_finish(lf)); 965 } 966 967 static int 968 link_elf_load_file(linker_class_t cls, const char* filename, 969 linker_file_t* result) 970 { 971 struct nameidata nd; 972 struct thread* td = curthread; /* XXX */ 973 Elf_Ehdr *hdr; 974 caddr_t firstpage, segbase; 975 int nbytes, i; 976 Elf_Phdr *phdr; 977 Elf_Phdr *phlimit; 978 Elf_Phdr *segs[MAXSEGS]; 979 int nsegs; 980 Elf_Phdr *phdyn; 981 caddr_t mapbase; 982 size_t mapsize; 983 Elf_Addr base_vaddr; 984 Elf_Addr base_vlimit; 985 int error = 0; 986 ssize_t resid; 987 int flags; 988 elf_file_t ef; 989 linker_file_t lf; 990 Elf_Shdr *shdr; 991 int symtabindex; 992 int symstrindex; 993 int shstrindex; 994 int symcnt; 995 int strcnt; 996 char *shstrs; 997 998 shdr = NULL; 999 lf = NULL; 1000 shstrs = NULL; 1001 1002 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename); 1003 flags = FREAD; 1004 error = vn_open(&nd, &flags, 0, NULL); 1005 if (error != 0) 1006 return (error); 1007 NDFREE_PNBUF(&nd); 1008 if (nd.ni_vp->v_type != VREG) { 1009 error = ENOEXEC; 1010 firstpage = NULL; 1011 goto out; 1012 } 1013 #ifdef MAC 1014 error = mac_kld_check_load(curthread->td_ucred, nd.ni_vp); 1015 if (error != 0) { 1016 firstpage = NULL; 1017 goto out; 1018 } 1019 #endif 1020 1021 /* 1022 * Read the elf header from the file. 1023 */ 1024 firstpage = malloc(PAGE_SIZE, M_LINKER, M_WAITOK); 1025 hdr = (Elf_Ehdr *)firstpage; 1026 error = vn_rdwr(UIO_READ, nd.ni_vp, firstpage, PAGE_SIZE, 0, 1027 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1028 &resid, td); 1029 nbytes = PAGE_SIZE - resid; 1030 if (error != 0) 1031 goto out; 1032 1033 if (!IS_ELF(*hdr)) { 1034 error = ENOEXEC; 1035 goto out; 1036 } 1037 1038 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 1039 hdr->e_ident[EI_DATA] != ELF_TARG_DATA) { 1040 link_elf_error(filename, "Unsupported file layout"); 1041 error = ENOEXEC; 1042 goto out; 1043 } 1044 if (hdr->e_ident[EI_VERSION] != EV_CURRENT || 1045 hdr->e_version != EV_CURRENT) { 1046 link_elf_error(filename, "Unsupported file version"); 1047 error = ENOEXEC; 1048 goto out; 1049 } 1050 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) { 1051 error = ENOSYS; 1052 goto out; 1053 } 1054 if (hdr->e_machine != ELF_TARG_MACH) { 1055 link_elf_error(filename, "Unsupported machine"); 1056 error = ENOEXEC; 1057 goto out; 1058 } 1059 1060 /* 1061 * We rely on the program header being in the first page. 1062 * This is not strictly required by the ABI specification, but 1063 * it seems to always true in practice. And, it simplifies 1064 * things considerably. 1065 */ 1066 if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) && 1067 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) && 1068 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes))) 1069 link_elf_error(filename, "Unreadable program headers"); 1070 1071 /* 1072 * Scan the program header entries, and save key information. 1073 * 1074 * We rely on there being exactly two load segments, text and data, 1075 * in that order. 1076 */ 1077 phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff); 1078 phlimit = phdr + hdr->e_phnum; 1079 nsegs = 0; 1080 phdyn = NULL; 1081 while (phdr < phlimit) { 1082 switch (phdr->p_type) { 1083 case PT_LOAD: 1084 if (nsegs == MAXSEGS) { 1085 link_elf_error(filename, "Too many sections"); 1086 error = ENOEXEC; 1087 goto out; 1088 } 1089 /* 1090 * XXX: We just trust they come in right order ?? 1091 */ 1092 segs[nsegs] = phdr; 1093 ++nsegs; 1094 break; 1095 1096 case PT_DYNAMIC: 1097 phdyn = phdr; 1098 break; 1099 1100 case PT_INTERP: 1101 error = ENOSYS; 1102 goto out; 1103 } 1104 1105 ++phdr; 1106 } 1107 if (phdyn == NULL) { 1108 link_elf_error(filename, "Object is not dynamically-linked"); 1109 error = ENOEXEC; 1110 goto out; 1111 } 1112 if (nsegs == 0) { 1113 link_elf_error(filename, "No sections"); 1114 error = ENOEXEC; 1115 goto out; 1116 } 1117 1118 /* 1119 * Allocate the entire address space of the object, to stake 1120 * out our contiguous region, and to establish the base 1121 * address for relocation. 1122 */ 1123 base_vaddr = trunc_page(segs[0]->p_vaddr); 1124 base_vlimit = round_page(segs[nsegs - 1]->p_vaddr + 1125 segs[nsegs - 1]->p_memsz); 1126 mapsize = base_vlimit - base_vaddr; 1127 1128 lf = linker_make_file(filename, &link_elf_class); 1129 if (lf == NULL) { 1130 error = ENOMEM; 1131 goto out; 1132 } 1133 1134 ef = (elf_file_t) lf; 1135 #ifdef SPARSE_MAPPING 1136 ef->object = vm_pager_allocate(OBJT_PHYS, NULL, mapsize, VM_PROT_ALL, 1137 0, thread0.td_ucred); 1138 if (ef->object == NULL) { 1139 error = ENOMEM; 1140 goto out; 1141 } 1142 #ifdef __amd64__ 1143 mapbase = (caddr_t)KERNBASE; 1144 #else 1145 mapbase = (caddr_t)vm_map_min(kernel_map); 1146 #endif 1147 /* 1148 * Mapping protections are downgraded after relocation processing. 1149 */ 1150 error = vm_map_find(kernel_map, ef->object, 0, 1151 (vm_offset_t *)&mapbase, mapsize, 0, VMFS_OPTIMAL_SPACE, 1152 VM_PROT_ALL, VM_PROT_ALL, 0); 1153 if (error != 0) { 1154 vm_object_deallocate(ef->object); 1155 ef->object = NULL; 1156 goto out; 1157 } 1158 #else 1159 mapbase = malloc_exec(mapsize, M_LINKER, M_WAITOK); 1160 #endif 1161 ef->address = mapbase; 1162 1163 /* 1164 * Read the text and data sections and zero the bss. 1165 */ 1166 for (i = 0; i < nsegs; i++) { 1167 segbase = mapbase + segs[i]->p_vaddr - base_vaddr; 1168 1169 #ifdef SPARSE_MAPPING 1170 /* 1171 * Consecutive segments may have different mapping permissions, 1172 * so be strict and verify that their mappings do not overlap. 1173 */ 1174 if (((vm_offset_t)segbase & PAGE_MASK) != 0) { 1175 error = EINVAL; 1176 goto out; 1177 } 1178 1179 error = vm_map_wire(kernel_map, 1180 (vm_offset_t)segbase, 1181 (vm_offset_t)segbase + round_page(segs[i]->p_memsz), 1182 VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES); 1183 if (error != KERN_SUCCESS) { 1184 error = ENOMEM; 1185 goto out; 1186 } 1187 #endif 1188 1189 error = vn_rdwr(UIO_READ, nd.ni_vp, 1190 segbase, segs[i]->p_filesz, segs[i]->p_offset, 1191 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1192 &resid, td); 1193 if (error != 0) 1194 goto out; 1195 bzero(segbase + segs[i]->p_filesz, 1196 segs[i]->p_memsz - segs[i]->p_filesz); 1197 } 1198 1199 ef->dynamic = (Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr); 1200 1201 lf->address = ef->address; 1202 lf->size = mapsize; 1203 1204 error = parse_dynamic(ef); 1205 if (error != 0) 1206 goto out; 1207 error = parse_dpcpu(ef); 1208 if (error != 0) 1209 goto out; 1210 #ifdef VIMAGE 1211 error = parse_vnet(ef); 1212 if (error != 0) 1213 goto out; 1214 #endif 1215 link_elf_reloc_local(lf); 1216 1217 VOP_UNLOCK(nd.ni_vp); 1218 error = linker_load_dependencies(lf); 1219 vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY); 1220 if (error != 0) 1221 goto out; 1222 error = relocate_file(ef); 1223 if (error != 0) 1224 goto out; 1225 1226 #ifdef SPARSE_MAPPING 1227 /* 1228 * Downgrade permissions on text segment mappings now that relocation 1229 * processing is complete. Restrict permissions on read-only segments. 1230 */ 1231 for (i = 0; i < nsegs; i++) { 1232 vm_prot_t prot; 1233 1234 if (segs[i]->p_type != PT_LOAD) 1235 continue; 1236 1237 prot = VM_PROT_READ; 1238 if ((segs[i]->p_flags & PF_W) != 0) 1239 prot |= VM_PROT_WRITE; 1240 if ((segs[i]->p_flags & PF_X) != 0) 1241 prot |= VM_PROT_EXECUTE; 1242 segbase = mapbase + segs[i]->p_vaddr - base_vaddr; 1243 error = vm_map_protect(kernel_map, 1244 (vm_offset_t)segbase, 1245 (vm_offset_t)segbase + round_page(segs[i]->p_memsz), 1246 prot, 0, VM_MAP_PROTECT_SET_PROT); 1247 if (error != KERN_SUCCESS) { 1248 error = ENOMEM; 1249 goto out; 1250 } 1251 } 1252 #endif 1253 1254 /* 1255 * Try and load the symbol table if it's present. (you can 1256 * strip it!) 1257 */ 1258 nbytes = hdr->e_shnum * hdr->e_shentsize; 1259 if (nbytes == 0 || hdr->e_shoff == 0) 1260 goto nosyms; 1261 shdr = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO); 1262 error = vn_rdwr(UIO_READ, nd.ni_vp, 1263 (caddr_t)shdr, nbytes, hdr->e_shoff, 1264 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1265 &resid, td); 1266 if (error != 0) 1267 goto out; 1268 1269 /* Read section string table */ 1270 shstrindex = hdr->e_shstrndx; 1271 if (shstrindex != 0 && shdr[shstrindex].sh_type == SHT_STRTAB && 1272 shdr[shstrindex].sh_size != 0) { 1273 nbytes = shdr[shstrindex].sh_size; 1274 shstrs = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO); 1275 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shstrs, nbytes, 1276 shdr[shstrindex].sh_offset, UIO_SYSSPACE, IO_NODELOCKED, 1277 td->td_ucred, NOCRED, &resid, td); 1278 if (error) 1279 goto out; 1280 } 1281 1282 symtabindex = -1; 1283 symstrindex = -1; 1284 for (i = 0; i < hdr->e_shnum; i++) { 1285 if (shdr[i].sh_type == SHT_SYMTAB) { 1286 symtabindex = i; 1287 symstrindex = shdr[i].sh_link; 1288 } else if (shstrs != NULL && shdr[i].sh_name != 0 && 1289 strcmp(shstrs + shdr[i].sh_name, ".ctors") == 0) { 1290 /* Record relocated address and size of .ctors. */ 1291 lf->ctors_addr = mapbase + shdr[i].sh_addr - base_vaddr; 1292 lf->ctors_size = shdr[i].sh_size; 1293 } 1294 } 1295 if (symtabindex < 0 || symstrindex < 0) 1296 goto nosyms; 1297 1298 symcnt = shdr[symtabindex].sh_size; 1299 ef->symbase = malloc(symcnt, M_LINKER, M_WAITOK); 1300 strcnt = shdr[symstrindex].sh_size; 1301 ef->strbase = malloc(strcnt, M_LINKER, M_WAITOK); 1302 1303 error = vn_rdwr(UIO_READ, nd.ni_vp, 1304 ef->symbase, symcnt, shdr[symtabindex].sh_offset, 1305 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1306 &resid, td); 1307 if (error != 0) 1308 goto out; 1309 error = vn_rdwr(UIO_READ, nd.ni_vp, 1310 ef->strbase, strcnt, shdr[symstrindex].sh_offset, 1311 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 1312 &resid, td); 1313 if (error != 0) 1314 goto out; 1315 1316 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym); 1317 ef->ddbsymtab = (const Elf_Sym *)ef->symbase; 1318 ef->ddbstrcnt = strcnt; 1319 ef->ddbstrtab = ef->strbase; 1320 1321 nosyms: 1322 1323 #ifdef __arm__ 1324 link_elf_locate_exidx(lf, shdr, hdr->e_shnum); 1325 #endif 1326 1327 error = link_elf_link_common_finish(lf); 1328 if (error != 0) 1329 goto out; 1330 1331 *result = lf; 1332 1333 out: 1334 VOP_UNLOCK(nd.ni_vp); 1335 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1336 if (error != 0 && lf != NULL) 1337 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1338 free(shdr, M_LINKER); 1339 free(firstpage, M_LINKER); 1340 free(shstrs, M_LINKER); 1341 1342 return (error); 1343 } 1344 1345 Elf_Addr 1346 elf_relocaddr(linker_file_t lf, Elf_Addr x) 1347 { 1348 elf_file_t ef; 1349 1350 KASSERT(lf->ops->cls == (kobj_class_t)&link_elf_class, 1351 ("elf_relocaddr: unexpected linker file %p", lf)); 1352 1353 ef = (elf_file_t)lf; 1354 if (x >= ef->pcpu_start && x < ef->pcpu_stop) 1355 return ((x - ef->pcpu_start) + ef->pcpu_base); 1356 #ifdef VIMAGE 1357 if (x >= ef->vnet_start && x < ef->vnet_stop) 1358 return ((x - ef->vnet_start) + ef->vnet_base); 1359 #endif 1360 return (x); 1361 } 1362 1363 static void 1364 link_elf_unload_file(linker_file_t file) 1365 { 1366 elf_file_t ef = (elf_file_t) file; 1367 1368 if (ef->pcpu_base != 0) { 1369 dpcpu_free((void *)ef->pcpu_base, 1370 ef->pcpu_stop - ef->pcpu_start); 1371 elf_set_delete(&set_pcpu_list, ef->pcpu_start); 1372 } 1373 #ifdef VIMAGE 1374 if (ef->vnet_base != 0) { 1375 vnet_data_free((void *)ef->vnet_base, 1376 ef->vnet_stop - ef->vnet_start); 1377 elf_set_delete(&set_vnet_list, ef->vnet_start); 1378 } 1379 #endif 1380 #ifdef GDB 1381 if (ef->gdb.l_ld != NULL) { 1382 GDB_STATE(RT_DELETE); 1383 free((void *)(uintptr_t)ef->gdb.l_name, M_LINKER); 1384 link_elf_delete_gdb(&ef->gdb); 1385 GDB_STATE(RT_CONSISTENT); 1386 } 1387 #endif 1388 1389 /* Notify MD code that a module is being unloaded. */ 1390 elf_cpu_unload_file(file); 1391 1392 if (ef->preloaded) { 1393 link_elf_unload_preload(file); 1394 return; 1395 } 1396 1397 #ifdef SPARSE_MAPPING 1398 if (ef->object != NULL) { 1399 vm_map_remove(kernel_map, (vm_offset_t) ef->address, 1400 (vm_offset_t) ef->address 1401 + (ef->object->size << PAGE_SHIFT)); 1402 } 1403 #else 1404 free(ef->address, M_LINKER); 1405 #endif 1406 free(ef->symbase, M_LINKER); 1407 free(ef->strbase, M_LINKER); 1408 free(ef->ctftab, M_LINKER); 1409 free(ef->ctfoff, M_LINKER); 1410 free(ef->typoff, M_LINKER); 1411 } 1412 1413 static void 1414 link_elf_unload_preload(linker_file_t file) 1415 { 1416 1417 if (file->pathname != NULL) 1418 preload_delete_name(file->pathname); 1419 } 1420 1421 static const char * 1422 symbol_name(elf_file_t ef, Elf_Size r_info) 1423 { 1424 const Elf_Sym *ref; 1425 1426 if (ELF_R_SYM(r_info)) { 1427 ref = ef->symtab + ELF_R_SYM(r_info); 1428 return (ef->strtab + ref->st_name); 1429 } 1430 return (NULL); 1431 } 1432 1433 static int 1434 symbol_type(elf_file_t ef, Elf_Size r_info) 1435 { 1436 const Elf_Sym *ref; 1437 1438 if (ELF_R_SYM(r_info)) { 1439 ref = ef->symtab + ELF_R_SYM(r_info); 1440 return (ELF_ST_TYPE(ref->st_info)); 1441 } 1442 return (STT_NOTYPE); 1443 } 1444 1445 static int 1446 relocate_file1(elf_file_t ef, elf_lookup_fn lookup, elf_reloc_fn reloc, 1447 bool ifuncs) 1448 { 1449 const Elf_Rel *rel; 1450 const Elf_Rela *rela; 1451 const char *symname; 1452 1453 TSENTER(); 1454 #define APPLY_RELOCS(iter, tbl, tblsize, type) do { \ 1455 for ((iter) = (tbl); (iter) != NULL && \ 1456 (iter) < (tbl) + (tblsize) / sizeof(*(iter)); (iter)++) { \ 1457 if ((symbol_type(ef, (iter)->r_info) == \ 1458 STT_GNU_IFUNC || \ 1459 elf_is_ifunc_reloc((iter)->r_info)) != ifuncs) \ 1460 continue; \ 1461 if (reloc(&ef->lf, (Elf_Addr)ef->address, \ 1462 (iter), (type), lookup)) { \ 1463 symname = symbol_name(ef, (iter)->r_info); \ 1464 printf("link_elf: symbol %s undefined\n", \ 1465 symname); \ 1466 return (ENOENT); \ 1467 } \ 1468 } \ 1469 } while (0) 1470 1471 APPLY_RELOCS(rel, ef->rel, ef->relsize, ELF_RELOC_REL); 1472 TSENTER2("ef->rela"); 1473 APPLY_RELOCS(rela, ef->rela, ef->relasize, ELF_RELOC_RELA); 1474 TSEXIT2("ef->rela"); 1475 APPLY_RELOCS(rel, ef->pltrel, ef->pltrelsize, ELF_RELOC_REL); 1476 APPLY_RELOCS(rela, ef->pltrela, ef->pltrelasize, ELF_RELOC_RELA); 1477 1478 #undef APPLY_RELOCS 1479 1480 TSEXIT(); 1481 return (0); 1482 } 1483 1484 static int 1485 relocate_file(elf_file_t ef) 1486 { 1487 int error; 1488 1489 error = relocate_file1(ef, elf_lookup, elf_reloc, false); 1490 if (error == 0) 1491 error = relocate_file1(ef, elf_lookup, elf_reloc, true); 1492 return (error); 1493 } 1494 1495 /* 1496 * SysV hash function for symbol table lookup. It is specified by the 1497 * System V ABI. 1498 */ 1499 static Elf32_Word 1500 elf_hash(const char *name) 1501 { 1502 const unsigned char *p = (const unsigned char *)name; 1503 Elf32_Word h = 0; 1504 1505 while (*p != '\0') { 1506 h = (h << 4) + *p++; 1507 h ^= (h >> 24) & 0xf0; 1508 } 1509 return (h & 0x0fffffff); 1510 } 1511 1512 static int 1513 link_elf_lookup_symbol1(linker_file_t lf, const char *name, c_linker_sym_t *sym, 1514 bool see_local) 1515 { 1516 elf_file_t ef = (elf_file_t) lf; 1517 unsigned long symnum; 1518 const Elf_Sym* symp; 1519 const char *strp; 1520 Elf32_Word hash; 1521 1522 /* If we don't have a hash, bail. */ 1523 if (ef->buckets == NULL || ef->nbuckets == 0) { 1524 printf("link_elf_lookup_symbol: missing symbol hash table\n"); 1525 return (ENOENT); 1526 } 1527 1528 /* First, search hashed global symbols */ 1529 hash = elf_hash(name); 1530 symnum = ef->buckets[hash % ef->nbuckets]; 1531 1532 while (symnum != STN_UNDEF) { 1533 if (symnum >= ef->nchains) { 1534 printf("%s: corrupt symbol table\n", __func__); 1535 return (ENOENT); 1536 } 1537 1538 symp = ef->symtab + symnum; 1539 if (symp->st_name == 0) { 1540 printf("%s: corrupt symbol table\n", __func__); 1541 return (ENOENT); 1542 } 1543 1544 strp = ef->strtab + symp->st_name; 1545 1546 if (strcmp(name, strp) == 0) { 1547 if (symp->st_shndx != SHN_UNDEF || 1548 (symp->st_value != 0 && 1549 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1550 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC))) { 1551 if (see_local || 1552 ELF_ST_BIND(symp->st_info) != STB_LOCAL) { 1553 *sym = (c_linker_sym_t) symp; 1554 return (0); 1555 } 1556 } 1557 return (ENOENT); 1558 } 1559 1560 symnum = ef->chains[symnum]; 1561 } 1562 1563 return (ENOENT); 1564 } 1565 1566 static int 1567 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym) 1568 { 1569 if (link_elf_leak_locals) 1570 return (link_elf_lookup_debug_symbol(lf, name, sym)); 1571 return (link_elf_lookup_symbol1(lf, name, sym, false)); 1572 } 1573 1574 static int 1575 link_elf_lookup_debug_symbol(linker_file_t lf, const char *name, 1576 c_linker_sym_t *sym) 1577 { 1578 elf_file_t ef = (elf_file_t)lf; 1579 const Elf_Sym* symp; 1580 const char *strp; 1581 int i; 1582 1583 if (link_elf_lookup_symbol1(lf, name, sym, true) == 0) 1584 return (0); 1585 1586 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1587 strp = ef->ddbstrtab + symp->st_name; 1588 if (strcmp(name, strp) == 0) { 1589 if (symp->st_shndx != SHN_UNDEF || 1590 (symp->st_value != 0 && 1591 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1592 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC))) { 1593 *sym = (c_linker_sym_t) symp; 1594 return (0); 1595 } 1596 return (ENOENT); 1597 } 1598 } 1599 1600 return (ENOENT); 1601 } 1602 1603 static int 1604 link_elf_lookup_debug_symbol_ctf(linker_file_t lf, const char *name, 1605 c_linker_sym_t *sym, linker_ctf_t *lc) 1606 { 1607 elf_file_t ef = (elf_file_t)lf; 1608 const Elf_Sym *symp; 1609 const char *strp; 1610 int i; 1611 1612 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1613 strp = ef->ddbstrtab + symp->st_name; 1614 if (strcmp(name, strp) == 0) { 1615 if (symp->st_shndx != SHN_UNDEF || 1616 (symp->st_value != 0 && 1617 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1618 ELF_ST_TYPE(symp->st_info) == 1619 STT_GNU_IFUNC))) { 1620 *sym = (c_linker_sym_t)symp; 1621 break; 1622 } 1623 return (ENOENT); 1624 } 1625 } 1626 1627 /* Populate CTF info structure if symbol was found. */ 1628 return (i < ef->ddbsymcnt ? link_elf_ctf_get_ddb(lf, lc) : ENOENT); 1629 } 1630 1631 static int 1632 link_elf_symbol_values1(linker_file_t lf, c_linker_sym_t sym, 1633 linker_symval_t *symval, bool see_local) 1634 { 1635 elf_file_t ef; 1636 const Elf_Sym *es; 1637 caddr_t val; 1638 1639 ef = (elf_file_t)lf; 1640 es = (const Elf_Sym *)sym; 1641 if (es >= ef->symtab && es < ef->symtab + ef->nchains) { 1642 if (!see_local && ELF_ST_BIND(es->st_info) == STB_LOCAL) 1643 return (ENOENT); 1644 symval->name = ef->strtab + es->st_name; 1645 val = (caddr_t)ef->address + es->st_value; 1646 if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC) 1647 val = ((caddr_t (*)(void))val)(); 1648 symval->value = val; 1649 symval->size = es->st_size; 1650 return (0); 1651 } 1652 return (ENOENT); 1653 } 1654 1655 static int 1656 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, 1657 linker_symval_t *symval) 1658 { 1659 if (link_elf_leak_locals) 1660 return (link_elf_debug_symbol_values(lf, sym, symval)); 1661 return (link_elf_symbol_values1(lf, sym, symval, false)); 1662 } 1663 1664 static int 1665 link_elf_debug_symbol_values(linker_file_t lf, c_linker_sym_t sym, 1666 linker_symval_t *symval) 1667 { 1668 elf_file_t ef = (elf_file_t)lf; 1669 const Elf_Sym *es = (const Elf_Sym *)sym; 1670 caddr_t val; 1671 1672 if (link_elf_symbol_values1(lf, sym, symval, true) == 0) 1673 return (0); 1674 if (ef->symtab == ef->ddbsymtab) 1675 return (ENOENT); 1676 1677 if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) { 1678 symval->name = ef->ddbstrtab + es->st_name; 1679 val = (caddr_t)ef->address + es->st_value; 1680 if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC) 1681 val = ((caddr_t (*)(void))val)(); 1682 symval->value = val; 1683 symval->size = es->st_size; 1684 return (0); 1685 } 1686 return (ENOENT); 1687 } 1688 1689 static int 1690 link_elf_search_symbol(linker_file_t lf, caddr_t value, 1691 c_linker_sym_t *sym, long *diffp) 1692 { 1693 elf_file_t ef = (elf_file_t)lf; 1694 u_long off = (uintptr_t)(void *)value; 1695 u_long diff = off; 1696 u_long st_value; 1697 const Elf_Sym *es; 1698 const Elf_Sym *best = NULL; 1699 int i; 1700 1701 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) { 1702 if (es->st_name == 0) 1703 continue; 1704 st_value = es->st_value + (uintptr_t) (void *) ef->address; 1705 if (off >= st_value) { 1706 if (off - st_value < diff) { 1707 diff = off - st_value; 1708 best = es; 1709 if (diff == 0) 1710 break; 1711 } else if (off - st_value == diff) { 1712 best = es; 1713 } 1714 } 1715 } 1716 if (best == NULL) 1717 *diffp = off; 1718 else 1719 *diffp = diff; 1720 *sym = (c_linker_sym_t) best; 1721 1722 return (0); 1723 } 1724 1725 /* 1726 * Look up a linker set on an ELF system. 1727 */ 1728 static int 1729 link_elf_lookup_set(linker_file_t lf, const char *name, 1730 void ***startp, void ***stopp, int *countp) 1731 { 1732 c_linker_sym_t sym; 1733 linker_symval_t symval; 1734 char *setsym; 1735 void **start, **stop; 1736 int len, error = 0, count; 1737 1738 len = strlen(name) + sizeof("__start_set_"); /* sizeof includes \0 */ 1739 setsym = malloc(len, M_LINKER, M_WAITOK); 1740 1741 /* get address of first entry */ 1742 snprintf(setsym, len, "%s%s", "__start_set_", name); 1743 error = link_elf_lookup_symbol(lf, setsym, &sym); 1744 if (error != 0) 1745 goto out; 1746 link_elf_symbol_values(lf, sym, &symval); 1747 if (symval.value == 0) { 1748 error = ESRCH; 1749 goto out; 1750 } 1751 start = (void **)symval.value; 1752 1753 /* get address of last entry */ 1754 snprintf(setsym, len, "%s%s", "__stop_set_", name); 1755 error = link_elf_lookup_symbol(lf, setsym, &sym); 1756 if (error != 0) 1757 goto out; 1758 link_elf_symbol_values(lf, sym, &symval); 1759 if (symval.value == 0) { 1760 error = ESRCH; 1761 goto out; 1762 } 1763 stop = (void **)symval.value; 1764 1765 /* and the number of entries */ 1766 count = stop - start; 1767 1768 /* and copy out */ 1769 if (startp != NULL) 1770 *startp = start; 1771 if (stopp != NULL) 1772 *stopp = stop; 1773 if (countp != NULL) 1774 *countp = count; 1775 1776 out: 1777 free(setsym, M_LINKER); 1778 return (error); 1779 } 1780 1781 static int 1782 link_elf_each_function_name(linker_file_t file, 1783 int (*callback)(const char *, void *), void *opaque) 1784 { 1785 elf_file_t ef = (elf_file_t)file; 1786 const Elf_Sym *symp; 1787 int i, error; 1788 1789 /* Exhaustive search */ 1790 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1791 if (symp->st_value != 0 && 1792 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1793 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) { 1794 error = callback(ef->ddbstrtab + symp->st_name, opaque); 1795 if (error != 0) 1796 return (error); 1797 } 1798 } 1799 return (0); 1800 } 1801 1802 static int 1803 link_elf_each_function_nameval(linker_file_t file, 1804 linker_function_nameval_callback_t callback, void *opaque) 1805 { 1806 linker_symval_t symval; 1807 elf_file_t ef = (elf_file_t)file; 1808 const Elf_Sym *symp; 1809 int i, error; 1810 1811 /* Exhaustive search */ 1812 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1813 if (symp->st_value != 0 && 1814 (ELF_ST_TYPE(symp->st_info) == STT_FUNC || 1815 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) { 1816 error = link_elf_debug_symbol_values(file, 1817 (c_linker_sym_t) symp, &symval); 1818 if (error == 0) 1819 error = callback(file, i, &symval, opaque); 1820 if (error != 0) 1821 return (error); 1822 } 1823 } 1824 return (0); 1825 } 1826 1827 const Elf_Sym * 1828 elf_get_sym(linker_file_t lf, Elf_Size symidx) 1829 { 1830 elf_file_t ef = (elf_file_t)lf; 1831 1832 if (symidx >= ef->nchains) 1833 return (NULL); 1834 return (ef->symtab + symidx); 1835 } 1836 1837 const char * 1838 elf_get_symname(linker_file_t lf, Elf_Size symidx) 1839 { 1840 elf_file_t ef = (elf_file_t)lf; 1841 const Elf_Sym *sym; 1842 1843 if (symidx >= ef->nchains) 1844 return (NULL); 1845 sym = ef->symtab + symidx; 1846 return (ef->strtab + sym->st_name); 1847 } 1848 1849 /* 1850 * Symbol lookup function that can be used when the symbol index is known (ie 1851 * in relocations). It uses the symbol index instead of doing a fully fledged 1852 * hash table based lookup when such is valid. For example for local symbols. 1853 * This is not only more efficient, it's also more correct. It's not always 1854 * the case that the symbol can be found through the hash table. 1855 */ 1856 static int 1857 elf_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *res) 1858 { 1859 elf_file_t ef = (elf_file_t)lf; 1860 const Elf_Sym *sym; 1861 const char *symbol; 1862 Elf_Addr addr, start, base; 1863 1864 /* Don't even try to lookup the symbol if the index is bogus. */ 1865 if (symidx >= ef->nchains) { 1866 *res = 0; 1867 return (EINVAL); 1868 } 1869 1870 sym = ef->symtab + symidx; 1871 1872 /* 1873 * Don't do a full lookup when the symbol is local. It may even 1874 * fail because it may not be found through the hash table. 1875 */ 1876 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) { 1877 /* Force lookup failure when we have an insanity. */ 1878 if (sym->st_shndx == SHN_UNDEF || sym->st_value == 0) { 1879 *res = 0; 1880 return (EINVAL); 1881 } 1882 *res = ((Elf_Addr)ef->address + sym->st_value); 1883 return (0); 1884 } 1885 1886 /* 1887 * XXX we can avoid doing a hash table based lookup for global 1888 * symbols as well. This however is not always valid, so we'll 1889 * just do it the hard way for now. Performance tweaks can 1890 * always be added. 1891 */ 1892 1893 symbol = ef->strtab + sym->st_name; 1894 1895 /* Force a lookup failure if the symbol name is bogus. */ 1896 if (*symbol == 0) { 1897 *res = 0; 1898 return (EINVAL); 1899 } 1900 1901 addr = ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps)); 1902 if (addr == 0 && ELF_ST_BIND(sym->st_info) != STB_WEAK) { 1903 *res = 0; 1904 return (EINVAL); 1905 } 1906 1907 if (elf_set_find(&set_pcpu_list, addr, &start, &base)) 1908 addr = addr - start + base; 1909 #ifdef VIMAGE 1910 else if (elf_set_find(&set_vnet_list, addr, &start, &base)) 1911 addr = addr - start + base; 1912 #endif 1913 *res = addr; 1914 return (0); 1915 } 1916 1917 static void 1918 link_elf_reloc_local(linker_file_t lf) 1919 { 1920 const Elf_Rel *rellim; 1921 const Elf_Rel *rel; 1922 const Elf_Rela *relalim; 1923 const Elf_Rela *rela; 1924 elf_file_t ef = (elf_file_t)lf; 1925 1926 /* Perform relocations without addend if there are any: */ 1927 if ((rel = ef->rel) != NULL) { 1928 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize); 1929 while (rel < rellim) { 1930 elf_reloc_local(lf, (Elf_Addr)ef->address, rel, 1931 ELF_RELOC_REL, elf_lookup); 1932 rel++; 1933 } 1934 } 1935 1936 /* Perform relocations with addend if there are any: */ 1937 if ((rela = ef->rela) != NULL) { 1938 relalim = (const Elf_Rela *) 1939 ((const char *)ef->rela + ef->relasize); 1940 while (rela < relalim) { 1941 elf_reloc_local(lf, (Elf_Addr)ef->address, rela, 1942 ELF_RELOC_RELA, elf_lookup); 1943 rela++; 1944 } 1945 } 1946 } 1947 1948 static long 1949 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab) 1950 { 1951 elf_file_t ef = (elf_file_t)lf; 1952 1953 *symtab = ef->ddbsymtab; 1954 1955 if (*symtab == NULL) 1956 return (0); 1957 1958 return (ef->ddbsymcnt); 1959 } 1960 1961 static long 1962 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab) 1963 { 1964 elf_file_t ef = (elf_file_t)lf; 1965 1966 *strtab = ef->ddbstrtab; 1967 1968 if (*strtab == NULL) 1969 return (0); 1970 1971 return (ef->ddbstrcnt); 1972 } 1973 1974 #ifdef VIMAGE 1975 static void 1976 link_elf_propagate_vnets(linker_file_t lf) 1977 { 1978 elf_file_t ef = (elf_file_t)lf; 1979 int size; 1980 1981 if (ef->vnet_base != 0) { 1982 size = (uintptr_t)ef->vnet_stop - (uintptr_t)ef->vnet_start; 1983 vnet_data_copy((void *)ef->vnet_base, size); 1984 } 1985 } 1986 #endif 1987 1988 #if defined(__i386__) || defined(__amd64__) || defined(__aarch64__) || defined(__powerpc__) 1989 /* 1990 * Use this lookup routine when performing relocations early during boot. 1991 * The generic lookup routine depends on kobj, which is not initialized 1992 * at that point. 1993 */ 1994 static int 1995 elf_lookup_ifunc(linker_file_t lf, Elf_Size symidx, int deps __unused, 1996 Elf_Addr *res) 1997 { 1998 elf_file_t ef; 1999 const Elf_Sym *symp; 2000 caddr_t val; 2001 2002 ef = (elf_file_t)lf; 2003 symp = ef->symtab + symidx; 2004 if (ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC) { 2005 val = (caddr_t)ef->address + symp->st_value; 2006 *res = ((Elf_Addr (*)(void))val)(); 2007 return (0); 2008 } 2009 return (ENOENT); 2010 } 2011 2012 void 2013 link_elf_ireloc(void) 2014 { 2015 struct elf_file eff; 2016 elf_file_t ef; 2017 2018 TSENTER(); 2019 ef = &eff; 2020 2021 bzero_early(ef, sizeof(*ef)); 2022 2023 ef->modptr = preload_kmdp; 2024 ef->dynamic = (Elf_Dyn *)&_DYNAMIC; 2025 2026 #ifdef RELOCATABLE_KERNEL 2027 ef->address = (caddr_t) (__startkernel - KERNBASE); 2028 #else 2029 ef->address = 0; 2030 #endif 2031 parse_dynamic(ef); 2032 2033 link_elf_preload_parse_symbols(ef); 2034 relocate_file1(ef, elf_lookup_ifunc, elf_reloc, true); 2035 TSEXIT(); 2036 } 2037 2038 #if defined(__aarch64__) || defined(__amd64__) 2039 void 2040 link_elf_late_ireloc(void) 2041 { 2042 elf_file_t ef; 2043 2044 KASSERT(linker_kernel_file != NULL, 2045 ("link_elf_late_ireloc: No kernel linker file found")); 2046 ef = (elf_file_t)linker_kernel_file; 2047 2048 relocate_file1(ef, elf_lookup_ifunc, elf_reloc_late, true); 2049 } 2050 #endif 2051 #endif 2052