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_obj.c
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1 /*- 2 * Copyright (c) 1998-2000 Doug Rabson 3 * Copyright (c) 2004 Peter Wemm 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD: releng/10.3/sys/kern/link_elf_obj.c 296469 2016-03-07 19:59:08Z dim $"); 30 31 #include "opt_ddb.h" 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/kernel.h> 36 #include <sys/lock.h> 37 #include <sys/malloc.h> 38 #include <sys/mutex.h> 39 #include <sys/mount.h> 40 #include <sys/proc.h> 41 #include <sys/namei.h> 42 #include <sys/fcntl.h> 43 #include <sys/vnode.h> 44 #include <sys/linker.h> 45 46 #include <machine/elf.h> 47 48 #include <net/vnet.h> 49 50 #include <security/mac/mac_framework.h> 51 52 #include <vm/vm.h> 53 #include <vm/vm_param.h> 54 #include <vm/vm_object.h> 55 #include <vm/vm_kern.h> 56 #include <vm/vm_extern.h> 57 #include <vm/pmap.h> 58 #include <vm/vm_map.h> 59 60 #include <sys/link_elf.h> 61 62 #ifdef DDB_CTF 63 #include <net/zlib.h> 64 #endif 65 66 #include "linker_if.h" 67 68 typedef struct { 69 void *addr; 70 Elf_Off size; 71 int flags; 72 int sec; /* Original section */ 73 char *name; 74 } Elf_progent; 75 76 typedef struct { 77 Elf_Rel *rel; 78 int nrel; 79 int sec; 80 } Elf_relent; 81 82 typedef struct { 83 Elf_Rela *rela; 84 int nrela; 85 int sec; 86 } Elf_relaent; 87 88 89 typedef struct elf_file { 90 struct linker_file lf; /* Common fields */ 91 92 int preloaded; 93 caddr_t address; /* Relocation address */ 94 vm_object_t object; /* VM object to hold file pages */ 95 Elf_Shdr *e_shdr; 96 97 Elf_progent *progtab; 98 int nprogtab; 99 100 Elf_relaent *relatab; 101 int nrelatab; 102 103 Elf_relent *reltab; 104 int nreltab; 105 106 Elf_Sym *ddbsymtab; /* The symbol table we are using */ 107 long ddbsymcnt; /* Number of symbols */ 108 caddr_t ddbstrtab; /* String table */ 109 long ddbstrcnt; /* number of bytes in string table */ 110 111 caddr_t shstrtab; /* Section name string table */ 112 long shstrcnt; /* number of bytes in string table */ 113 114 caddr_t ctftab; /* CTF table */ 115 long ctfcnt; /* number of bytes in CTF table */ 116 caddr_t ctfoff; /* CTF offset table */ 117 caddr_t typoff; /* Type offset table */ 118 long typlen; /* Number of type entries. */ 119 120 } *elf_file_t; 121 122 #include <kern/kern_ctf.c> 123 124 static int link_elf_link_preload(linker_class_t cls, 125 const char *, linker_file_t *); 126 static int link_elf_link_preload_finish(linker_file_t); 127 static int link_elf_load_file(linker_class_t, const char *, linker_file_t *); 128 static int link_elf_lookup_symbol(linker_file_t, const char *, 129 c_linker_sym_t *); 130 static int link_elf_symbol_values(linker_file_t, c_linker_sym_t, 131 linker_symval_t *); 132 static int link_elf_search_symbol(linker_file_t, caddr_t value, 133 c_linker_sym_t *sym, long *diffp); 134 135 static void link_elf_unload_file(linker_file_t); 136 static int link_elf_lookup_set(linker_file_t, const char *, 137 void ***, void ***, int *); 138 static int link_elf_each_function_name(linker_file_t, 139 int (*)(const char *, void *), void *); 140 static int link_elf_each_function_nameval(linker_file_t, 141 linker_function_nameval_callback_t, 142 void *); 143 static void link_elf_reloc_local(linker_file_t); 144 static long link_elf_symtab_get(linker_file_t, const Elf_Sym **); 145 static long link_elf_strtab_get(linker_file_t, caddr_t *); 146 147 static int elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, 148 Elf_Addr *); 149 150 static kobj_method_t link_elf_methods[] = { 151 KOBJMETHOD(linker_lookup_symbol, link_elf_lookup_symbol), 152 KOBJMETHOD(linker_symbol_values, link_elf_symbol_values), 153 KOBJMETHOD(linker_search_symbol, link_elf_search_symbol), 154 KOBJMETHOD(linker_unload, link_elf_unload_file), 155 KOBJMETHOD(linker_load_file, link_elf_load_file), 156 KOBJMETHOD(linker_link_preload, link_elf_link_preload), 157 KOBJMETHOD(linker_link_preload_finish, link_elf_link_preload_finish), 158 KOBJMETHOD(linker_lookup_set, link_elf_lookup_set), 159 KOBJMETHOD(linker_each_function_name, link_elf_each_function_name), 160 KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval), 161 KOBJMETHOD(linker_ctf_get, link_elf_ctf_get), 162 KOBJMETHOD(linker_symtab_get, link_elf_symtab_get), 163 KOBJMETHOD(linker_strtab_get, link_elf_strtab_get), 164 { 0, 0 } 165 }; 166 167 static struct linker_class link_elf_class = { 168 #if ELF_TARG_CLASS == ELFCLASS32 169 "elf32_obj", 170 #else 171 "elf64_obj", 172 #endif 173 link_elf_methods, sizeof(struct elf_file) 174 }; 175 176 static int relocate_file(elf_file_t ef); 177 static void elf_obj_cleanup_globals_cache(elf_file_t); 178 179 static void 180 link_elf_error(const char *filename, const char *s) 181 { 182 if (filename == NULL) 183 printf("kldload: %s\n", s); 184 else 185 printf("kldload: %s: %s\n", filename, s); 186 } 187 188 static void 189 link_elf_init(void *arg) 190 { 191 192 linker_add_class(&link_elf_class); 193 } 194 195 SYSINIT(link_elf_obj, SI_SUB_KLD, SI_ORDER_SECOND, link_elf_init, 0); 196 197 static int 198 link_elf_link_preload(linker_class_t cls, const char *filename, 199 linker_file_t *result) 200 { 201 Elf_Ehdr *hdr; 202 Elf_Shdr *shdr; 203 Elf_Sym *es; 204 void *modptr, *baseptr, *sizeptr; 205 char *type; 206 elf_file_t ef; 207 linker_file_t lf; 208 Elf_Addr off; 209 int error, i, j, pb, ra, rl, shstrindex, symstrindex, symtabindex; 210 211 /* Look to see if we have the file preloaded */ 212 modptr = preload_search_by_name(filename); 213 if (modptr == NULL) 214 return ENOENT; 215 216 type = (char *)preload_search_info(modptr, MODINFO_TYPE); 217 baseptr = preload_search_info(modptr, MODINFO_ADDR); 218 sizeptr = preload_search_info(modptr, MODINFO_SIZE); 219 hdr = (Elf_Ehdr *)preload_search_info(modptr, MODINFO_METADATA | 220 MODINFOMD_ELFHDR); 221 shdr = (Elf_Shdr *)preload_search_info(modptr, MODINFO_METADATA | 222 MODINFOMD_SHDR); 223 if (type == NULL || (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) 224 " obj module") != 0 && 225 strcmp(type, "elf obj module") != 0)) { 226 return (EFTYPE); 227 } 228 if (baseptr == NULL || sizeptr == NULL || hdr == NULL || 229 shdr == NULL) 230 return (EINVAL); 231 232 lf = linker_make_file(filename, &link_elf_class); 233 if (lf == NULL) 234 return (ENOMEM); 235 236 ef = (elf_file_t)lf; 237 ef->preloaded = 1; 238 ef->address = *(caddr_t *)baseptr; 239 lf->address = *(caddr_t *)baseptr; 240 lf->size = *(size_t *)sizeptr; 241 242 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 243 hdr->e_ident[EI_DATA] != ELF_TARG_DATA || 244 hdr->e_ident[EI_VERSION] != EV_CURRENT || 245 hdr->e_version != EV_CURRENT || 246 hdr->e_type != ET_REL || 247 hdr->e_machine != ELF_TARG_MACH) { 248 error = EFTYPE; 249 goto out; 250 } 251 ef->e_shdr = shdr; 252 253 /* Scan the section header for information and table sizing. */ 254 symtabindex = -1; 255 symstrindex = -1; 256 for (i = 0; i < hdr->e_shnum; i++) { 257 switch (shdr[i].sh_type) { 258 case SHT_PROGBITS: 259 case SHT_NOBITS: 260 #ifdef __amd64__ 261 case SHT_AMD64_UNWIND: 262 #endif 263 ef->nprogtab++; 264 break; 265 case SHT_SYMTAB: 266 symtabindex = i; 267 symstrindex = shdr[i].sh_link; 268 break; 269 case SHT_REL: 270 ef->nreltab++; 271 break; 272 case SHT_RELA: 273 ef->nrelatab++; 274 break; 275 } 276 } 277 278 shstrindex = hdr->e_shstrndx; 279 if (ef->nprogtab == 0 || symstrindex < 0 || 280 symstrindex >= hdr->e_shnum || 281 shdr[symstrindex].sh_type != SHT_STRTAB || shstrindex == 0 || 282 shstrindex >= hdr->e_shnum || 283 shdr[shstrindex].sh_type != SHT_STRTAB) { 284 printf("%s: bad/missing section headers\n", filename); 285 error = ENOEXEC; 286 goto out; 287 } 288 289 /* Allocate space for tracking the load chunks */ 290 if (ef->nprogtab != 0) 291 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab), 292 M_LINKER, M_WAITOK | M_ZERO); 293 if (ef->nreltab != 0) 294 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab), 295 M_LINKER, M_WAITOK | M_ZERO); 296 if (ef->nrelatab != 0) 297 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab), 298 M_LINKER, M_WAITOK | M_ZERO); 299 if ((ef->nprogtab != 0 && ef->progtab == NULL) || 300 (ef->nreltab != 0 && ef->reltab == NULL) || 301 (ef->nrelatab != 0 && ef->relatab == NULL)) { 302 error = ENOMEM; 303 goto out; 304 } 305 306 /* XXX, relocate the sh_addr fields saved by the loader. */ 307 off = 0; 308 for (i = 0; i < hdr->e_shnum; i++) { 309 if (shdr[i].sh_addr != 0 && (off == 0 || shdr[i].sh_addr < off)) 310 off = shdr[i].sh_addr; 311 } 312 for (i = 0; i < hdr->e_shnum; i++) { 313 if (shdr[i].sh_addr != 0) 314 shdr[i].sh_addr = shdr[i].sh_addr - off + 315 (Elf_Addr)ef->address; 316 } 317 318 ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym); 319 ef->ddbsymtab = (Elf_Sym *)shdr[symtabindex].sh_addr; 320 ef->ddbstrcnt = shdr[symstrindex].sh_size; 321 ef->ddbstrtab = (char *)shdr[symstrindex].sh_addr; 322 ef->shstrcnt = shdr[shstrindex].sh_size; 323 ef->shstrtab = (char *)shdr[shstrindex].sh_addr; 324 325 /* Now fill out progtab and the relocation tables. */ 326 pb = 0; 327 rl = 0; 328 ra = 0; 329 for (i = 0; i < hdr->e_shnum; i++) { 330 switch (shdr[i].sh_type) { 331 case SHT_PROGBITS: 332 case SHT_NOBITS: 333 #ifdef __amd64__ 334 case SHT_AMD64_UNWIND: 335 #endif 336 ef->progtab[pb].addr = (void *)shdr[i].sh_addr; 337 if (shdr[i].sh_type == SHT_PROGBITS) 338 ef->progtab[pb].name = "<<PROGBITS>>"; 339 #ifdef __amd64__ 340 else if (shdr[i].sh_type == SHT_AMD64_UNWIND) 341 ef->progtab[pb].name = "<<UNWIND>>"; 342 #endif 343 else 344 ef->progtab[pb].name = "<<NOBITS>>"; 345 ef->progtab[pb].size = shdr[i].sh_size; 346 ef->progtab[pb].sec = i; 347 if (ef->shstrtab && shdr[i].sh_name != 0) 348 ef->progtab[pb].name = 349 ef->shstrtab + shdr[i].sh_name; 350 if (ef->progtab[pb].name != NULL && 351 !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) { 352 void *dpcpu; 353 354 dpcpu = dpcpu_alloc(shdr[i].sh_size); 355 if (dpcpu == NULL) { 356 error = ENOSPC; 357 goto out; 358 } 359 memcpy(dpcpu, ef->progtab[pb].addr, 360 ef->progtab[pb].size); 361 dpcpu_copy(dpcpu, shdr[i].sh_size); 362 ef->progtab[pb].addr = dpcpu; 363 #ifdef VIMAGE 364 } else if (ef->progtab[pb].name != NULL && 365 !strcmp(ef->progtab[pb].name, VNET_SETNAME)) { 366 void *vnet_data; 367 368 vnet_data = vnet_data_alloc(shdr[i].sh_size); 369 if (vnet_data == NULL) { 370 error = ENOSPC; 371 goto out; 372 } 373 memcpy(vnet_data, ef->progtab[pb].addr, 374 ef->progtab[pb].size); 375 vnet_data_copy(vnet_data, shdr[i].sh_size); 376 ef->progtab[pb].addr = vnet_data; 377 #endif 378 } 379 380 /* Update all symbol values with the offset. */ 381 for (j = 0; j < ef->ddbsymcnt; j++) { 382 es = &ef->ddbsymtab[j]; 383 if (es->st_shndx != i) 384 continue; 385 es->st_value += (Elf_Addr)ef->progtab[pb].addr; 386 } 387 pb++; 388 break; 389 case SHT_REL: 390 ef->reltab[rl].rel = (Elf_Rel *)shdr[i].sh_addr; 391 ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel); 392 ef->reltab[rl].sec = shdr[i].sh_info; 393 rl++; 394 break; 395 case SHT_RELA: 396 ef->relatab[ra].rela = (Elf_Rela *)shdr[i].sh_addr; 397 ef->relatab[ra].nrela = 398 shdr[i].sh_size / sizeof(Elf_Rela); 399 ef->relatab[ra].sec = shdr[i].sh_info; 400 ra++; 401 break; 402 } 403 } 404 if (pb != ef->nprogtab) 405 panic("lost progbits"); 406 if (rl != ef->nreltab) 407 panic("lost reltab"); 408 if (ra != ef->nrelatab) 409 panic("lost relatab"); 410 411 /* Local intra-module relocations */ 412 link_elf_reloc_local(lf); 413 414 *result = lf; 415 return (0); 416 417 out: 418 /* preload not done this way */ 419 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 420 return (error); 421 } 422 423 static int 424 link_elf_link_preload_finish(linker_file_t lf) 425 { 426 elf_file_t ef; 427 int error; 428 429 ef = (elf_file_t)lf; 430 error = relocate_file(ef); 431 if (error) 432 return error; 433 434 /* Notify MD code that a module is being loaded. */ 435 error = elf_cpu_load_file(lf); 436 if (error) 437 return (error); 438 439 return (0); 440 } 441 442 static int 443 link_elf_load_file(linker_class_t cls, const char *filename, 444 linker_file_t *result) 445 { 446 struct nameidata nd; 447 struct thread *td = curthread; /* XXX */ 448 Elf_Ehdr *hdr; 449 Elf_Shdr *shdr; 450 Elf_Sym *es; 451 int nbytes, i, j; 452 vm_offset_t mapbase; 453 size_t mapsize; 454 int error = 0; 455 ssize_t resid; 456 int flags; 457 elf_file_t ef; 458 linker_file_t lf; 459 int symtabindex; 460 int symstrindex; 461 int shstrindex; 462 int nsym; 463 int pb, rl, ra; 464 int alignmask; 465 466 shdr = NULL; 467 lf = NULL; 468 mapsize = 0; 469 hdr = NULL; 470 471 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename, td); 472 flags = FREAD; 473 error = vn_open(&nd, &flags, 0, NULL); 474 if (error) 475 return error; 476 NDFREE(&nd, NDF_ONLY_PNBUF); 477 if (nd.ni_vp->v_type != VREG) { 478 error = ENOEXEC; 479 goto out; 480 } 481 #ifdef MAC 482 error = mac_kld_check_load(td->td_ucred, nd.ni_vp); 483 if (error) { 484 goto out; 485 } 486 #endif 487 488 /* Read the elf header from the file. */ 489 hdr = malloc(sizeof(*hdr), M_LINKER, M_WAITOK); 490 error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)hdr, sizeof(*hdr), 0, 491 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 492 &resid, td); 493 if (error) 494 goto out; 495 if (resid != 0){ 496 error = ENOEXEC; 497 goto out; 498 } 499 500 if (!IS_ELF(*hdr)) { 501 error = ENOEXEC; 502 goto out; 503 } 504 505 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS 506 || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) { 507 link_elf_error(filename, "Unsupported file layout"); 508 error = ENOEXEC; 509 goto out; 510 } 511 if (hdr->e_ident[EI_VERSION] != EV_CURRENT 512 || hdr->e_version != EV_CURRENT) { 513 link_elf_error(filename, "Unsupported file version"); 514 error = ENOEXEC; 515 goto out; 516 } 517 if (hdr->e_type != ET_REL) { 518 error = ENOSYS; 519 goto out; 520 } 521 if (hdr->e_machine != ELF_TARG_MACH) { 522 link_elf_error(filename, "Unsupported machine"); 523 error = ENOEXEC; 524 goto out; 525 } 526 527 lf = linker_make_file(filename, &link_elf_class); 528 if (!lf) { 529 error = ENOMEM; 530 goto out; 531 } 532 ef = (elf_file_t) lf; 533 ef->nprogtab = 0; 534 ef->e_shdr = 0; 535 ef->nreltab = 0; 536 ef->nrelatab = 0; 537 538 /* Allocate and read in the section header */ 539 nbytes = hdr->e_shnum * hdr->e_shentsize; 540 if (nbytes == 0 || hdr->e_shoff == 0 || 541 hdr->e_shentsize != sizeof(Elf_Shdr)) { 542 error = ENOEXEC; 543 goto out; 544 } 545 shdr = malloc(nbytes, M_LINKER, M_WAITOK); 546 ef->e_shdr = shdr; 547 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shdr, nbytes, hdr->e_shoff, 548 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, &resid, td); 549 if (error) 550 goto out; 551 if (resid) { 552 error = ENOEXEC; 553 goto out; 554 } 555 556 /* Scan the section header for information and table sizing. */ 557 nsym = 0; 558 symtabindex = -1; 559 symstrindex = -1; 560 for (i = 0; i < hdr->e_shnum; i++) { 561 if (shdr[i].sh_size == 0) 562 continue; 563 switch (shdr[i].sh_type) { 564 case SHT_PROGBITS: 565 case SHT_NOBITS: 566 #ifdef __amd64__ 567 case SHT_AMD64_UNWIND: 568 #endif 569 ef->nprogtab++; 570 break; 571 case SHT_SYMTAB: 572 nsym++; 573 symtabindex = i; 574 symstrindex = shdr[i].sh_link; 575 break; 576 case SHT_REL: 577 ef->nreltab++; 578 break; 579 case SHT_RELA: 580 ef->nrelatab++; 581 break; 582 case SHT_STRTAB: 583 break; 584 } 585 } 586 if (ef->nprogtab == 0) { 587 link_elf_error(filename, "file has no contents"); 588 error = ENOEXEC; 589 goto out; 590 } 591 if (nsym != 1) { 592 /* Only allow one symbol table for now */ 593 link_elf_error(filename, "file has no valid symbol table"); 594 error = ENOEXEC; 595 goto out; 596 } 597 if (symstrindex < 0 || symstrindex > hdr->e_shnum || 598 shdr[symstrindex].sh_type != SHT_STRTAB) { 599 link_elf_error(filename, "file has invalid symbol strings"); 600 error = ENOEXEC; 601 goto out; 602 } 603 604 /* Allocate space for tracking the load chunks */ 605 if (ef->nprogtab != 0) 606 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab), 607 M_LINKER, M_WAITOK | M_ZERO); 608 if (ef->nreltab != 0) 609 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab), 610 M_LINKER, M_WAITOK | M_ZERO); 611 if (ef->nrelatab != 0) 612 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab), 613 M_LINKER, M_WAITOK | M_ZERO); 614 615 if (symtabindex == -1) 616 panic("lost symbol table index"); 617 /* Allocate space for and load the symbol table */ 618 ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym); 619 ef->ddbsymtab = malloc(shdr[symtabindex].sh_size, M_LINKER, M_WAITOK); 620 error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)ef->ddbsymtab, 621 shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset, 622 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 623 &resid, td); 624 if (error) 625 goto out; 626 if (resid != 0){ 627 error = EINVAL; 628 goto out; 629 } 630 631 if (symstrindex == -1) 632 panic("lost symbol string index"); 633 /* Allocate space for and load the symbol strings */ 634 ef->ddbstrcnt = shdr[symstrindex].sh_size; 635 ef->ddbstrtab = malloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK); 636 error = vn_rdwr(UIO_READ, nd.ni_vp, ef->ddbstrtab, 637 shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset, 638 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 639 &resid, td); 640 if (error) 641 goto out; 642 if (resid != 0){ 643 error = EINVAL; 644 goto out; 645 } 646 647 /* Do we have a string table for the section names? */ 648 shstrindex = -1; 649 if (hdr->e_shstrndx != 0 && 650 shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) { 651 shstrindex = hdr->e_shstrndx; 652 ef->shstrcnt = shdr[shstrindex].sh_size; 653 ef->shstrtab = malloc(shdr[shstrindex].sh_size, M_LINKER, 654 M_WAITOK); 655 error = vn_rdwr(UIO_READ, nd.ni_vp, ef->shstrtab, 656 shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset, 657 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 658 &resid, td); 659 if (error) 660 goto out; 661 if (resid != 0){ 662 error = EINVAL; 663 goto out; 664 } 665 } 666 667 /* Size up code/data(progbits) and bss(nobits). */ 668 alignmask = 0; 669 for (i = 0; i < hdr->e_shnum; i++) { 670 if (shdr[i].sh_size == 0) 671 continue; 672 switch (shdr[i].sh_type) { 673 case SHT_PROGBITS: 674 case SHT_NOBITS: 675 #ifdef __amd64__ 676 case SHT_AMD64_UNWIND: 677 #endif 678 alignmask = shdr[i].sh_addralign - 1; 679 mapsize += alignmask; 680 mapsize &= ~alignmask; 681 mapsize += shdr[i].sh_size; 682 break; 683 } 684 } 685 686 /* 687 * We know how much space we need for the text/data/bss/etc. 688 * This stuff needs to be in a single chunk so that profiling etc 689 * can get the bounds and gdb can associate offsets with modules 690 */ 691 ef->object = vm_object_allocate(OBJT_DEFAULT, 692 round_page(mapsize) >> PAGE_SHIFT); 693 if (ef->object == NULL) { 694 error = ENOMEM; 695 goto out; 696 } 697 ef->address = (caddr_t) vm_map_min(kernel_map); 698 699 /* 700 * In order to satisfy amd64's architectural requirements on the 701 * location of code and data in the kernel's address space, request a 702 * mapping that is above the kernel. 703 */ 704 #ifdef __amd64__ 705 mapbase = KERNBASE; 706 #else 707 mapbase = VM_MIN_KERNEL_ADDRESS; 708 #endif 709 error = vm_map_find(kernel_map, ef->object, 0, &mapbase, 710 round_page(mapsize), 0, VMFS_OPTIMAL_SPACE, VM_PROT_ALL, 711 VM_PROT_ALL, 0); 712 if (error) { 713 vm_object_deallocate(ef->object); 714 ef->object = 0; 715 goto out; 716 } 717 718 /* Wire the pages */ 719 error = vm_map_wire(kernel_map, mapbase, 720 mapbase + round_page(mapsize), 721 VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES); 722 if (error != KERN_SUCCESS) { 723 error = ENOMEM; 724 goto out; 725 } 726 727 /* Inform the kld system about the situation */ 728 lf->address = ef->address = (caddr_t)mapbase; 729 lf->size = mapsize; 730 731 /* 732 * Now load code/data(progbits), zero bss(nobits), allocate space for 733 * and load relocs 734 */ 735 pb = 0; 736 rl = 0; 737 ra = 0; 738 alignmask = 0; 739 for (i = 0; i < hdr->e_shnum; i++) { 740 if (shdr[i].sh_size == 0) 741 continue; 742 switch (shdr[i].sh_type) { 743 case SHT_PROGBITS: 744 case SHT_NOBITS: 745 #ifdef __amd64__ 746 case SHT_AMD64_UNWIND: 747 #endif 748 alignmask = shdr[i].sh_addralign - 1; 749 mapbase += alignmask; 750 mapbase &= ~alignmask; 751 if (ef->shstrtab && shdr[i].sh_name != 0) 752 ef->progtab[pb].name = 753 ef->shstrtab + shdr[i].sh_name; 754 else if (shdr[i].sh_type == SHT_PROGBITS) 755 ef->progtab[pb].name = "<<PROGBITS>>"; 756 #ifdef __amd64__ 757 else if (shdr[i].sh_type == SHT_AMD64_UNWIND) 758 ef->progtab[pb].name = "<<UNWIND>>"; 759 #endif 760 else 761 ef->progtab[pb].name = "<<NOBITS>>"; 762 if (ef->progtab[pb].name != NULL && 763 !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) 764 ef->progtab[pb].addr = 765 dpcpu_alloc(shdr[i].sh_size); 766 #ifdef VIMAGE 767 else if (ef->progtab[pb].name != NULL && 768 !strcmp(ef->progtab[pb].name, VNET_SETNAME)) 769 ef->progtab[pb].addr = 770 vnet_data_alloc(shdr[i].sh_size); 771 #endif 772 else 773 ef->progtab[pb].addr = 774 (void *)(uintptr_t)mapbase; 775 if (ef->progtab[pb].addr == NULL) { 776 error = ENOSPC; 777 goto out; 778 } 779 ef->progtab[pb].size = shdr[i].sh_size; 780 ef->progtab[pb].sec = i; 781 if (shdr[i].sh_type == SHT_PROGBITS 782 #ifdef __amd64__ 783 || shdr[i].sh_type == SHT_AMD64_UNWIND 784 #endif 785 ) { 786 error = vn_rdwr(UIO_READ, nd.ni_vp, 787 ef->progtab[pb].addr, 788 shdr[i].sh_size, shdr[i].sh_offset, 789 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 790 NOCRED, &resid, td); 791 if (error) 792 goto out; 793 if (resid != 0){ 794 error = EINVAL; 795 goto out; 796 } 797 /* Initialize the per-cpu or vnet area. */ 798 if (ef->progtab[pb].addr != (void *)mapbase && 799 !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) 800 dpcpu_copy(ef->progtab[pb].addr, 801 shdr[i].sh_size); 802 #ifdef VIMAGE 803 else if (ef->progtab[pb].addr != 804 (void *)mapbase && 805 !strcmp(ef->progtab[pb].name, VNET_SETNAME)) 806 vnet_data_copy(ef->progtab[pb].addr, 807 shdr[i].sh_size); 808 #endif 809 } else 810 bzero(ef->progtab[pb].addr, shdr[i].sh_size); 811 812 /* Update all symbol values with the offset. */ 813 for (j = 0; j < ef->ddbsymcnt; j++) { 814 es = &ef->ddbsymtab[j]; 815 if (es->st_shndx != i) 816 continue; 817 es->st_value += (Elf_Addr)ef->progtab[pb].addr; 818 } 819 mapbase += shdr[i].sh_size; 820 pb++; 821 break; 822 case SHT_REL: 823 ef->reltab[rl].rel = malloc(shdr[i].sh_size, M_LINKER, 824 M_WAITOK); 825 ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel); 826 ef->reltab[rl].sec = shdr[i].sh_info; 827 error = vn_rdwr(UIO_READ, nd.ni_vp, 828 (void *)ef->reltab[rl].rel, 829 shdr[i].sh_size, shdr[i].sh_offset, 830 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 831 &resid, td); 832 if (error) 833 goto out; 834 if (resid != 0){ 835 error = EINVAL; 836 goto out; 837 } 838 rl++; 839 break; 840 case SHT_RELA: 841 ef->relatab[ra].rela = malloc(shdr[i].sh_size, M_LINKER, 842 M_WAITOK); 843 ef->relatab[ra].nrela = 844 shdr[i].sh_size / sizeof(Elf_Rela); 845 ef->relatab[ra].sec = shdr[i].sh_info; 846 error = vn_rdwr(UIO_READ, nd.ni_vp, 847 (void *)ef->relatab[ra].rela, 848 shdr[i].sh_size, shdr[i].sh_offset, 849 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 850 &resid, td); 851 if (error) 852 goto out; 853 if (resid != 0){ 854 error = EINVAL; 855 goto out; 856 } 857 ra++; 858 break; 859 } 860 } 861 if (pb != ef->nprogtab) 862 panic("lost progbits"); 863 if (rl != ef->nreltab) 864 panic("lost reltab"); 865 if (ra != ef->nrelatab) 866 panic("lost relatab"); 867 if (mapbase != (vm_offset_t)ef->address + mapsize) 868 panic("mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n", 869 (u_long)mapbase, ef->address, (u_long)mapsize, 870 (u_long)(vm_offset_t)ef->address + mapsize); 871 872 /* Local intra-module relocations */ 873 link_elf_reloc_local(lf); 874 875 /* Pull in dependencies */ 876 VOP_UNLOCK(nd.ni_vp, 0); 877 error = linker_load_dependencies(lf); 878 vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY); 879 if (error) 880 goto out; 881 882 /* External relocations */ 883 error = relocate_file(ef); 884 if (error) 885 goto out; 886 887 /* Notify MD code that a module is being loaded. */ 888 error = elf_cpu_load_file(lf); 889 if (error) 890 goto out; 891 892 *result = lf; 893 894 out: 895 VOP_UNLOCK(nd.ni_vp, 0); 896 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 897 if (error && lf) 898 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 899 if (hdr) 900 free(hdr, M_LINKER); 901 902 return error; 903 } 904 905 static void 906 link_elf_unload_file(linker_file_t file) 907 { 908 elf_file_t ef = (elf_file_t) file; 909 int i; 910 911 /* Notify MD code that a module is being unloaded. */ 912 elf_cpu_unload_file(file); 913 914 if (ef->progtab) { 915 for (i = 0; i < ef->nprogtab; i++) { 916 if (ef->progtab[i].size == 0) 917 continue; 918 if (ef->progtab[i].name == NULL) 919 continue; 920 if (!strcmp(ef->progtab[i].name, DPCPU_SETNAME)) 921 dpcpu_free(ef->progtab[i].addr, 922 ef->progtab[i].size); 923 #ifdef VIMAGE 924 else if (!strcmp(ef->progtab[i].name, VNET_SETNAME)) 925 vnet_data_free(ef->progtab[i].addr, 926 ef->progtab[i].size); 927 #endif 928 } 929 } 930 if (ef->preloaded) { 931 if (ef->reltab) 932 free(ef->reltab, M_LINKER); 933 if (ef->relatab) 934 free(ef->relatab, M_LINKER); 935 if (ef->progtab) 936 free(ef->progtab, M_LINKER); 937 if (ef->ctftab) 938 free(ef->ctftab, M_LINKER); 939 if (ef->ctfoff) 940 free(ef->ctfoff, M_LINKER); 941 if (ef->typoff) 942 free(ef->typoff, M_LINKER); 943 if (file->filename != NULL) 944 preload_delete_name(file->filename); 945 /* XXX reclaim module memory? */ 946 return; 947 } 948 949 for (i = 0; i < ef->nreltab; i++) 950 if (ef->reltab[i].rel) 951 free(ef->reltab[i].rel, M_LINKER); 952 for (i = 0; i < ef->nrelatab; i++) 953 if (ef->relatab[i].rela) 954 free(ef->relatab[i].rela, M_LINKER); 955 if (ef->reltab) 956 free(ef->reltab, M_LINKER); 957 if (ef->relatab) 958 free(ef->relatab, M_LINKER); 959 if (ef->progtab) 960 free(ef->progtab, M_LINKER); 961 962 if (ef->object) { 963 vm_map_remove(kernel_map, (vm_offset_t) ef->address, 964 (vm_offset_t) ef->address + 965 (ef->object->size << PAGE_SHIFT)); 966 } 967 if (ef->e_shdr) 968 free(ef->e_shdr, M_LINKER); 969 if (ef->ddbsymtab) 970 free(ef->ddbsymtab, M_LINKER); 971 if (ef->ddbstrtab) 972 free(ef->ddbstrtab, M_LINKER); 973 if (ef->shstrtab) 974 free(ef->shstrtab, M_LINKER); 975 if (ef->ctftab) 976 free(ef->ctftab, M_LINKER); 977 if (ef->ctfoff) 978 free(ef->ctfoff, M_LINKER); 979 if (ef->typoff) 980 free(ef->typoff, M_LINKER); 981 } 982 983 static const char * 984 symbol_name(elf_file_t ef, Elf_Size r_info) 985 { 986 const Elf_Sym *ref; 987 988 if (ELF_R_SYM(r_info)) { 989 ref = ef->ddbsymtab + ELF_R_SYM(r_info); 990 return ef->ddbstrtab + ref->st_name; 991 } else 992 return NULL; 993 } 994 995 static Elf_Addr 996 findbase(elf_file_t ef, int sec) 997 { 998 int i; 999 Elf_Addr base = 0; 1000 1001 for (i = 0; i < ef->nprogtab; i++) { 1002 if (sec == ef->progtab[i].sec) { 1003 base = (Elf_Addr)ef->progtab[i].addr; 1004 break; 1005 } 1006 } 1007 return base; 1008 } 1009 1010 static int 1011 relocate_file(elf_file_t ef) 1012 { 1013 const Elf_Rel *rellim; 1014 const Elf_Rel *rel; 1015 const Elf_Rela *relalim; 1016 const Elf_Rela *rela; 1017 const char *symname; 1018 const Elf_Sym *sym; 1019 int i; 1020 Elf_Size symidx; 1021 Elf_Addr base; 1022 1023 1024 /* Perform relocations without addend if there are any: */ 1025 for (i = 0; i < ef->nreltab; i++) { 1026 rel = ef->reltab[i].rel; 1027 if (rel == NULL) 1028 panic("lost a reltab!"); 1029 rellim = rel + ef->reltab[i].nrel; 1030 base = findbase(ef, ef->reltab[i].sec); 1031 if (base == 0) 1032 panic("lost base for reltab"); 1033 for ( ; rel < rellim; rel++) { 1034 symidx = ELF_R_SYM(rel->r_info); 1035 if (symidx >= ef->ddbsymcnt) 1036 continue; 1037 sym = ef->ddbsymtab + symidx; 1038 /* Local relocs are already done */ 1039 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) 1040 continue; 1041 if (elf_reloc(&ef->lf, base, rel, ELF_RELOC_REL, 1042 elf_obj_lookup)) { 1043 symname = symbol_name(ef, rel->r_info); 1044 printf("link_elf_obj: symbol %s undefined\n", 1045 symname); 1046 return ENOENT; 1047 } 1048 } 1049 } 1050 1051 /* Perform relocations with addend if there are any: */ 1052 for (i = 0; i < ef->nrelatab; i++) { 1053 rela = ef->relatab[i].rela; 1054 if (rela == NULL) 1055 panic("lost a relatab!"); 1056 relalim = rela + ef->relatab[i].nrela; 1057 base = findbase(ef, ef->relatab[i].sec); 1058 if (base == 0) 1059 panic("lost base for relatab"); 1060 for ( ; rela < relalim; rela++) { 1061 symidx = ELF_R_SYM(rela->r_info); 1062 if (symidx >= ef->ddbsymcnt) 1063 continue; 1064 sym = ef->ddbsymtab + symidx; 1065 /* Local relocs are already done */ 1066 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) 1067 continue; 1068 if (elf_reloc(&ef->lf, base, rela, ELF_RELOC_RELA, 1069 elf_obj_lookup)) { 1070 symname = symbol_name(ef, rela->r_info); 1071 printf("link_elf_obj: symbol %s undefined\n", 1072 symname); 1073 return ENOENT; 1074 } 1075 } 1076 } 1077 1078 /* 1079 * Only clean SHN_FBSD_CACHED for successfull return. If we 1080 * modified symbol table for the object but found an 1081 * unresolved symbol, there is no reason to roll back. 1082 */ 1083 elf_obj_cleanup_globals_cache(ef); 1084 1085 return 0; 1086 } 1087 1088 static int 1089 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym) 1090 { 1091 elf_file_t ef = (elf_file_t) lf; 1092 const Elf_Sym *symp; 1093 const char *strp; 1094 int i; 1095 1096 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1097 strp = ef->ddbstrtab + symp->st_name; 1098 if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) { 1099 *sym = (c_linker_sym_t) symp; 1100 return 0; 1101 } 1102 } 1103 return ENOENT; 1104 } 1105 1106 static int 1107 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, 1108 linker_symval_t *symval) 1109 { 1110 elf_file_t ef = (elf_file_t) lf; 1111 const Elf_Sym *es = (const Elf_Sym*) sym; 1112 1113 if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) { 1114 symval->name = ef->ddbstrtab + es->st_name; 1115 symval->value = (caddr_t)es->st_value; 1116 symval->size = es->st_size; 1117 return 0; 1118 } 1119 return ENOENT; 1120 } 1121 1122 static int 1123 link_elf_search_symbol(linker_file_t lf, caddr_t value, 1124 c_linker_sym_t *sym, long *diffp) 1125 { 1126 elf_file_t ef = (elf_file_t) lf; 1127 u_long off = (uintptr_t) (void *) value; 1128 u_long diff = off; 1129 u_long st_value; 1130 const Elf_Sym *es; 1131 const Elf_Sym *best = 0; 1132 int i; 1133 1134 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) { 1135 if (es->st_name == 0) 1136 continue; 1137 st_value = es->st_value; 1138 if (off >= st_value) { 1139 if (off - st_value < diff) { 1140 diff = off - st_value; 1141 best = es; 1142 if (diff == 0) 1143 break; 1144 } else if (off - st_value == diff) { 1145 best = es; 1146 } 1147 } 1148 } 1149 if (best == 0) 1150 *diffp = off; 1151 else 1152 *diffp = diff; 1153 *sym = (c_linker_sym_t) best; 1154 1155 return 0; 1156 } 1157 1158 /* 1159 * Look up a linker set on an ELF system. 1160 */ 1161 static int 1162 link_elf_lookup_set(linker_file_t lf, const char *name, 1163 void ***startp, void ***stopp, int *countp) 1164 { 1165 elf_file_t ef = (elf_file_t)lf; 1166 void **start, **stop; 1167 int i, count; 1168 1169 /* Relative to section number */ 1170 for (i = 0; i < ef->nprogtab; i++) { 1171 if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) && 1172 strcmp(ef->progtab[i].name + 4, name) == 0) { 1173 start = (void **)ef->progtab[i].addr; 1174 stop = (void **)((char *)ef->progtab[i].addr + 1175 ef->progtab[i].size); 1176 count = stop - start; 1177 if (startp) 1178 *startp = start; 1179 if (stopp) 1180 *stopp = stop; 1181 if (countp) 1182 *countp = count; 1183 return (0); 1184 } 1185 } 1186 return (ESRCH); 1187 } 1188 1189 static int 1190 link_elf_each_function_name(linker_file_t file, 1191 int (*callback)(const char *, void *), void *opaque) 1192 { 1193 elf_file_t ef = (elf_file_t)file; 1194 const Elf_Sym *symp; 1195 int i, error; 1196 1197 /* Exhaustive search */ 1198 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1199 if (symp->st_value != 0 && 1200 ELF_ST_TYPE(symp->st_info) == STT_FUNC) { 1201 error = callback(ef->ddbstrtab + symp->st_name, opaque); 1202 if (error) 1203 return (error); 1204 } 1205 } 1206 return (0); 1207 } 1208 1209 static int 1210 link_elf_each_function_nameval(linker_file_t file, 1211 linker_function_nameval_callback_t callback, void *opaque) 1212 { 1213 linker_symval_t symval; 1214 elf_file_t ef = (elf_file_t)file; 1215 const Elf_Sym* symp; 1216 int i, error; 1217 1218 /* Exhaustive search */ 1219 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1220 if (symp->st_value != 0 && 1221 ELF_ST_TYPE(symp->st_info) == STT_FUNC) { 1222 error = link_elf_symbol_values(file, (c_linker_sym_t) symp, &symval); 1223 if (error) 1224 return (error); 1225 error = callback(file, i, &symval, opaque); 1226 if (error) 1227 return (error); 1228 } 1229 } 1230 return (0); 1231 } 1232 1233 static void 1234 elf_obj_cleanup_globals_cache(elf_file_t ef) 1235 { 1236 Elf_Sym *sym; 1237 Elf_Size i; 1238 1239 for (i = 0; i < ef->ddbsymcnt; i++) { 1240 sym = ef->ddbsymtab + i; 1241 if (sym->st_shndx == SHN_FBSD_CACHED) { 1242 sym->st_shndx = SHN_UNDEF; 1243 sym->st_value = 0; 1244 } 1245 } 1246 } 1247 1248 /* 1249 * Symbol lookup function that can be used when the symbol index is known (ie 1250 * in relocations). It uses the symbol index instead of doing a fully fledged 1251 * hash table based lookup when such is valid. For example for local symbols. 1252 * This is not only more efficient, it's also more correct. It's not always 1253 * the case that the symbol can be found through the hash table. 1254 */ 1255 static int 1256 elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *res) 1257 { 1258 elf_file_t ef = (elf_file_t)lf; 1259 Elf_Sym *sym; 1260 const char *symbol; 1261 Elf_Addr res1; 1262 1263 /* Don't even try to lookup the symbol if the index is bogus. */ 1264 if (symidx >= ef->ddbsymcnt) { 1265 *res = 0; 1266 return (EINVAL); 1267 } 1268 1269 sym = ef->ddbsymtab + symidx; 1270 1271 /* Quick answer if there is a definition included. */ 1272 if (sym->st_shndx != SHN_UNDEF) { 1273 *res = sym->st_value; 1274 return (0); 1275 } 1276 1277 /* If we get here, then it is undefined and needs a lookup. */ 1278 switch (ELF_ST_BIND(sym->st_info)) { 1279 case STB_LOCAL: 1280 /* Local, but undefined? huh? */ 1281 *res = 0; 1282 return (EINVAL); 1283 1284 case STB_GLOBAL: 1285 case STB_WEAK: 1286 /* Relative to Data or Function name */ 1287 symbol = ef->ddbstrtab + sym->st_name; 1288 1289 /* Force a lookup failure if the symbol name is bogus. */ 1290 if (*symbol == 0) { 1291 *res = 0; 1292 return (EINVAL); 1293 } 1294 res1 = (Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps); 1295 1296 /* 1297 * Cache global lookups during module relocation. The failure 1298 * case is particularly expensive for callers, who must scan 1299 * through the entire globals table doing strcmp(). Cache to 1300 * avoid doing such work repeatedly. 1301 * 1302 * After relocation is complete, undefined globals will be 1303 * restored to SHN_UNDEF in elf_obj_cleanup_globals_cache(), 1304 * above. 1305 */ 1306 if (res1 != 0) { 1307 sym->st_shndx = SHN_FBSD_CACHED; 1308 sym->st_value = res1; 1309 *res = res1; 1310 return (0); 1311 } else if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { 1312 sym->st_value = 0; 1313 *res = 0; 1314 return (0); 1315 } 1316 return (EINVAL); 1317 1318 default: 1319 return (EINVAL); 1320 } 1321 } 1322 1323 static void 1324 link_elf_fix_link_set(elf_file_t ef) 1325 { 1326 static const char startn[] = "__start_"; 1327 static const char stopn[] = "__stop_"; 1328 Elf_Sym *sym; 1329 const char *sym_name, *linkset_name; 1330 Elf_Addr startp, stopp; 1331 Elf_Size symidx; 1332 int start, i; 1333 1334 startp = stopp = 0; 1335 for (symidx = 1 /* zero entry is special */; 1336 symidx < ef->ddbsymcnt; symidx++) { 1337 sym = ef->ddbsymtab + symidx; 1338 if (sym->st_shndx != SHN_UNDEF) 1339 continue; 1340 1341 sym_name = ef->ddbstrtab + sym->st_name; 1342 if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) { 1343 start = 1; 1344 linkset_name = sym_name + sizeof(startn) - 1; 1345 } 1346 else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) { 1347 start = 0; 1348 linkset_name = sym_name + sizeof(stopn) - 1; 1349 } 1350 else 1351 continue; 1352 1353 for (i = 0; i < ef->nprogtab; i++) { 1354 if (strcmp(ef->progtab[i].name, linkset_name) == 0) { 1355 startp = (Elf_Addr)ef->progtab[i].addr; 1356 stopp = (Elf_Addr)(startp + ef->progtab[i].size); 1357 break; 1358 } 1359 } 1360 if (i == ef->nprogtab) 1361 continue; 1362 1363 sym->st_value = start ? startp : stopp; 1364 sym->st_shndx = i; 1365 } 1366 } 1367 1368 static void 1369 link_elf_reloc_local(linker_file_t lf) 1370 { 1371 elf_file_t ef = (elf_file_t)lf; 1372 const Elf_Rel *rellim; 1373 const Elf_Rel *rel; 1374 const Elf_Rela *relalim; 1375 const Elf_Rela *rela; 1376 const Elf_Sym *sym; 1377 Elf_Addr base; 1378 int i; 1379 Elf_Size symidx; 1380 1381 link_elf_fix_link_set(ef); 1382 1383 /* Perform relocations without addend if there are any: */ 1384 for (i = 0; i < ef->nreltab; i++) { 1385 rel = ef->reltab[i].rel; 1386 if (rel == NULL) 1387 panic("lost a reltab!"); 1388 rellim = rel + ef->reltab[i].nrel; 1389 base = findbase(ef, ef->reltab[i].sec); 1390 if (base == 0) 1391 panic("lost base for reltab"); 1392 for ( ; rel < rellim; rel++) { 1393 symidx = ELF_R_SYM(rel->r_info); 1394 if (symidx >= ef->ddbsymcnt) 1395 continue; 1396 sym = ef->ddbsymtab + symidx; 1397 /* Only do local relocs */ 1398 if (ELF_ST_BIND(sym->st_info) != STB_LOCAL) 1399 continue; 1400 elf_reloc_local(lf, base, rel, ELF_RELOC_REL, 1401 elf_obj_lookup); 1402 } 1403 } 1404 1405 /* Perform relocations with addend if there are any: */ 1406 for (i = 0; i < ef->nrelatab; i++) { 1407 rela = ef->relatab[i].rela; 1408 if (rela == NULL) 1409 panic("lost a relatab!"); 1410 relalim = rela + ef->relatab[i].nrela; 1411 base = findbase(ef, ef->relatab[i].sec); 1412 if (base == 0) 1413 panic("lost base for relatab"); 1414 for ( ; rela < relalim; rela++) { 1415 symidx = ELF_R_SYM(rela->r_info); 1416 if (symidx >= ef->ddbsymcnt) 1417 continue; 1418 sym = ef->ddbsymtab + symidx; 1419 /* Only do local relocs */ 1420 if (ELF_ST_BIND(sym->st_info) != STB_LOCAL) 1421 continue; 1422 elf_reloc_local(lf, base, rela, ELF_RELOC_RELA, 1423 elf_obj_lookup); 1424 } 1425 } 1426 } 1427 1428 static long 1429 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab) 1430 { 1431 elf_file_t ef = (elf_file_t)lf; 1432 1433 *symtab = ef->ddbsymtab; 1434 1435 if (*symtab == NULL) 1436 return (0); 1437 1438 return (ef->ddbsymcnt); 1439 } 1440 1441 static long 1442 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab) 1443 { 1444 elf_file_t ef = (elf_file_t)lf; 1445 1446 *strtab = ef->ddbstrtab; 1447 1448 if (*strtab == NULL) 1449 return (0); 1450 1451 return (ef->ddbstrcnt); 1452 }
Cache object: d7b2c0154a0b500223764173e201b00c
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