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("$FreeBSD$"); 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 68typedef struct { 69 void *addr; 70 Elf_Off size; 71 int flags; 72 int sec; /* Original section */ 73 char *name; 74} Elf_progent; 75 76typedef struct { 77 Elf_Rel *rel; 78 int nrel; 79 int sec; 80} Elf_relent; 81 82typedef struct { 83 Elf_Rela *rela; 84 int nrela; 85 int sec; 86} Elf_relaent; 87 88 89typedef 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 124static int link_elf_link_preload(linker_class_t cls, 125 const char *, linker_file_t *); 126static int link_elf_link_preload_finish(linker_file_t); 127static int link_elf_load_file(linker_class_t, const char *, linker_file_t *); 128static int link_elf_lookup_symbol(linker_file_t, const char *, 129 c_linker_sym_t *); 130static int link_elf_symbol_values(linker_file_t, c_linker_sym_t, 131 linker_symval_t *); 132static int link_elf_search_symbol(linker_file_t, caddr_t value, 133 c_linker_sym_t *sym, long *diffp); 134 135static void link_elf_unload_file(linker_file_t); 136static int link_elf_lookup_set(linker_file_t, const char *, 137 void ***, void ***, int *); 138static int link_elf_each_function_name(linker_file_t, 139 int (*)(const char *, void *), void *); 140static int link_elf_each_function_nameval(linker_file_t, 141 linker_function_nameval_callback_t, 142 void *); 143static int link_elf_reloc_local(linker_file_t); 144static long link_elf_symtab_get(linker_file_t, const Elf_Sym **); 145static long link_elf_strtab_get(linker_file_t, caddr_t *); 146 147static int elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, 148 Elf_Addr *); 149 150static 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 167static 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 176static int relocate_file(elf_file_t ef); 177static void elf_obj_cleanup_globals_cache(elf_file_t); 178 179static void 180link_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 188static void 189link_elf_init(void *arg) 190{ 191 192 linker_add_class(&link_elf_class); 193} 194 195SYSINIT(link_elf_obj, SI_SUB_KLD, SI_ORDER_SECOND, link_elf_init, 0); 196 197static int 198link_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 printf("%s: lost progbits\n", filename); 406 error = ENOEXEC; 407 goto out; 408 } 409 if (rl != ef->nreltab) { 410 printf("%s: lost reltab\n", filename); 411 error = ENOEXEC; 412 goto out; 413 } 414 if (ra != ef->nrelatab) { 415 printf("%s: lost relatab\n", filename); 416 error = ENOEXEC; 417 goto out; 418 } 419 420 /* Local intra-module relocations */ 421 error = link_elf_reloc_local(lf); 422 if (error != 0) 423 goto out; 424 425 *result = lf; 426 return (0); 427 428out: 429 /* preload not done this way */ 430 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 431 return (error); 432} 433 434static int 435link_elf_link_preload_finish(linker_file_t lf) 436{ 437 elf_file_t ef; 438 int error; 439 440 ef = (elf_file_t)lf; 441 error = relocate_file(ef); 442 if (error) 443 return error; 444 445 /* Notify MD code that a module is being loaded. */ 446 error = elf_cpu_load_file(lf); 447 if (error) 448 return (error); 449 450 return (0); 451} 452 453static int 454link_elf_load_file(linker_class_t cls, const char *filename, 455 linker_file_t *result) 456{ 457 struct nameidata nd; 458 struct thread *td = curthread; /* XXX */ 459 Elf_Ehdr *hdr; 460 Elf_Shdr *shdr; 461 Elf_Sym *es; 462 int nbytes, i, j; 463 vm_offset_t mapbase; 464 size_t mapsize; 465 int error = 0; 466 ssize_t resid; 467 int flags; 468 elf_file_t ef; 469 linker_file_t lf; 470 int symtabindex; 471 int symstrindex; 472 int shstrindex; 473 int nsym; 474 int pb, rl, ra; 475 int alignmask; 476 477 shdr = NULL; 478 lf = NULL; 479 mapsize = 0; 480 hdr = NULL; 481 482 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename, td); 483 flags = FREAD; 484 error = vn_open(&nd, &flags, 0, NULL); 485 if (error) 486 return error; 487 NDFREE(&nd, NDF_ONLY_PNBUF); 488 if (nd.ni_vp->v_type != VREG) { 489 error = ENOEXEC; 490 goto out; 491 } 492#ifdef MAC 493 error = mac_kld_check_load(td->td_ucred, nd.ni_vp); 494 if (error) { 495 goto out; 496 } 497#endif 498 499 /* Read the elf header from the file. */ 500 hdr = malloc(sizeof(*hdr), M_LINKER, M_WAITOK); 501 error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)hdr, sizeof(*hdr), 0, 502 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 503 &resid, td); 504 if (error) 505 goto out; 506 if (resid != 0){ 507 error = ENOEXEC; 508 goto out; 509 } 510 511 if (!IS_ELF(*hdr)) { 512 error = ENOEXEC; 513 goto out; 514 } 515 516 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS 517 || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) { 518 link_elf_error(filename, "Unsupported file layout"); 519 error = ENOEXEC; 520 goto out; 521 } 522 if (hdr->e_ident[EI_VERSION] != EV_CURRENT 523 || hdr->e_version != EV_CURRENT) { 524 link_elf_error(filename, "Unsupported file version"); 525 error = ENOEXEC; 526 goto out; 527 } 528 if (hdr->e_type != ET_REL) { 529 error = ENOSYS; 530 goto out; 531 } 532 if (hdr->e_machine != ELF_TARG_MACH) { 533 link_elf_error(filename, "Unsupported machine"); 534 error = ENOEXEC; 535 goto out; 536 } 537 538 lf = linker_make_file(filename, &link_elf_class); 539 if (!lf) { 540 error = ENOMEM; 541 goto out; 542 } 543 ef = (elf_file_t) lf; 544 ef->nprogtab = 0; 545 ef->e_shdr = 0; 546 ef->nreltab = 0; 547 ef->nrelatab = 0; 548 549 /* Allocate and read in the section header */ 550 nbytes = hdr->e_shnum * hdr->e_shentsize; 551 if (nbytes == 0 || hdr->e_shoff == 0 || 552 hdr->e_shentsize != sizeof(Elf_Shdr)) { 553 error = ENOEXEC; 554 goto out; 555 } 556 shdr = malloc(nbytes, M_LINKER, M_WAITOK); 557 ef->e_shdr = shdr; 558 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shdr, nbytes, hdr->e_shoff, 559 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, &resid, td); 560 if (error) 561 goto out; 562 if (resid) { 563 error = ENOEXEC; 564 goto out; 565 } 566 567 /* Scan the section header for information and table sizing. */ 568 nsym = 0; 569 symtabindex = -1; 570 symstrindex = -1; 571 for (i = 0; i < hdr->e_shnum; i++) { 572 if (shdr[i].sh_size == 0) 573 continue; 574 switch (shdr[i].sh_type) { 575 case SHT_PROGBITS: 576 case SHT_NOBITS: 577#ifdef __amd64__ 578 case SHT_AMD64_UNWIND: 579#endif 580 ef->nprogtab++; 581 break; 582 case SHT_SYMTAB: 583 nsym++; 584 symtabindex = i; 585 symstrindex = shdr[i].sh_link; 586 break; 587 case SHT_REL: 588 ef->nreltab++; 589 break; 590 case SHT_RELA: 591 ef->nrelatab++; 592 break; 593 case SHT_STRTAB: 594 break; 595 } 596 } 597 if (ef->nprogtab == 0) { 598 link_elf_error(filename, "file has no contents"); 599 error = ENOEXEC; 600 goto out; 601 } 602 if (nsym != 1) { 603 /* Only allow one symbol table for now */ 604 link_elf_error(filename, "file has no valid symbol table"); 605 error = ENOEXEC; 606 goto out; 607 } 608 if (symstrindex < 0 || symstrindex > hdr->e_shnum || 609 shdr[symstrindex].sh_type != SHT_STRTAB) { 610 link_elf_error(filename, "file has invalid symbol strings"); 611 error = ENOEXEC; 612 goto out; 613 } 614 615 /* Allocate space for tracking the load chunks */ 616 if (ef->nprogtab != 0) 617 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab), 618 M_LINKER, M_WAITOK | M_ZERO); 619 if (ef->nreltab != 0) 620 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab), 621 M_LINKER, M_WAITOK | M_ZERO); 622 if (ef->nrelatab != 0) 623 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab), 624 M_LINKER, M_WAITOK | M_ZERO); 625 626 if (symtabindex == -1) { 627 link_elf_error(filename, "lost symbol table index"); 628 error = ENOEXEC; 629 goto out; 630 } 631 /* Allocate space for and load the symbol table */ 632 ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym); 633 ef->ddbsymtab = malloc(shdr[symtabindex].sh_size, M_LINKER, M_WAITOK); 634 error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)ef->ddbsymtab, 635 shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset, 636 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 637 &resid, td); 638 if (error) 639 goto out; 640 if (resid != 0){ 641 error = EINVAL; 642 goto out; 643 } 644 645 if (symstrindex == -1) { 646 link_elf_error(filename, "lost symbol string index"); 647 error = ENOEXEC; 648 goto out; 649 } 650 /* Allocate space for and load the symbol strings */ 651 ef->ddbstrcnt = shdr[symstrindex].sh_size; 652 ef->ddbstrtab = malloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK); 653 error = vn_rdwr(UIO_READ, nd.ni_vp, ef->ddbstrtab, 654 shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset, 655 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 656 &resid, td); 657 if (error) 658 goto out; 659 if (resid != 0){ 660 error = EINVAL; 661 goto out; 662 } 663 664 /* Do we have a string table for the section names? */ 665 shstrindex = -1; 666 if (hdr->e_shstrndx != 0 && 667 shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) { 668 shstrindex = hdr->e_shstrndx; 669 ef->shstrcnt = shdr[shstrindex].sh_size; 670 ef->shstrtab = malloc(shdr[shstrindex].sh_size, M_LINKER, 671 M_WAITOK); 672 error = vn_rdwr(UIO_READ, nd.ni_vp, ef->shstrtab, 673 shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset, 674 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 675 &resid, td); 676 if (error) 677 goto out; 678 if (resid != 0){ 679 error = EINVAL; 680 goto out; 681 } 682 } 683 684 /* Size up code/data(progbits) and bss(nobits). */ 685 alignmask = 0; 686 for (i = 0; i < hdr->e_shnum; i++) { 687 if (shdr[i].sh_size == 0) 688 continue; 689 switch (shdr[i].sh_type) { 690 case SHT_PROGBITS: 691 case SHT_NOBITS: 692#ifdef __amd64__ 693 case SHT_AMD64_UNWIND: 694#endif 695 alignmask = shdr[i].sh_addralign - 1; 696 mapsize += alignmask; 697 mapsize &= ~alignmask; 698 mapsize += shdr[i].sh_size; 699 break; 700 } 701 } 702 703 /* 704 * We know how much space we need for the text/data/bss/etc. 705 * This stuff needs to be in a single chunk so that profiling etc 706 * can get the bounds and gdb can associate offsets with modules 707 */ 708 ef->object = vm_object_allocate(OBJT_DEFAULT, 709 round_page(mapsize) >> PAGE_SHIFT); 710 if (ef->object == NULL) { 711 error = ENOMEM; 712 goto out; 713 } 714 ef->address = (caddr_t) vm_map_min(kernel_map); 715 716 /* 717 * In order to satisfy amd64's architectural requirements on the 718 * location of code and data in the kernel's address space, request a 719 * mapping that is above the kernel. 720 */ 721#ifdef __amd64__ 722 mapbase = KERNBASE; 723#else 724 mapbase = VM_MIN_KERNEL_ADDRESS; 725#endif 726 error = vm_map_find(kernel_map, ef->object, 0, &mapbase, 727 round_page(mapsize), 0, VMFS_OPTIMAL_SPACE, VM_PROT_ALL, 728 VM_PROT_ALL, 0); 729 if (error) { 730 vm_object_deallocate(ef->object); 731 ef->object = 0; 732 goto out; 733 } 734 735 /* Wire the pages */ 736 error = vm_map_wire(kernel_map, mapbase, 737 mapbase + round_page(mapsize), 738 VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES); 739 if (error != KERN_SUCCESS) { 740 error = ENOMEM; 741 goto out; 742 } 743 744 /* Inform the kld system about the situation */ 745 lf->address = ef->address = (caddr_t)mapbase; 746 lf->size = mapsize; 747 748 /* 749 * Now load code/data(progbits), zero bss(nobits), allocate space for 750 * and load relocs 751 */ 752 pb = 0; 753 rl = 0; 754 ra = 0; 755 alignmask = 0; 756 for (i = 0; i < hdr->e_shnum; i++) { 757 if (shdr[i].sh_size == 0) 758 continue; 759 switch (shdr[i].sh_type) { 760 case SHT_PROGBITS: 761 case SHT_NOBITS: 762#ifdef __amd64__ 763 case SHT_AMD64_UNWIND: 764#endif 765 alignmask = shdr[i].sh_addralign - 1; 766 mapbase += alignmask; 767 mapbase &= ~alignmask; 768 if (ef->shstrtab && shdr[i].sh_name != 0) 769 ef->progtab[pb].name = 770 ef->shstrtab + shdr[i].sh_name; 771 else if (shdr[i].sh_type == SHT_PROGBITS) 772 ef->progtab[pb].name = "<<PROGBITS>>"; 773#ifdef __amd64__ 774 else if (shdr[i].sh_type == SHT_AMD64_UNWIND) 775 ef->progtab[pb].name = "<<UNWIND>>"; 776#endif 777 else 778 ef->progtab[pb].name = "<<NOBITS>>"; 779 if (ef->progtab[pb].name != NULL && 780 !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) 781 ef->progtab[pb].addr = 782 dpcpu_alloc(shdr[i].sh_size); 783#ifdef VIMAGE 784 else if (ef->progtab[pb].name != NULL && 785 !strcmp(ef->progtab[pb].name, VNET_SETNAME)) 786 ef->progtab[pb].addr = 787 vnet_data_alloc(shdr[i].sh_size); 788#endif 789 else 790 ef->progtab[pb].addr = 791 (void *)(uintptr_t)mapbase; 792 if (ef->progtab[pb].addr == NULL) { 793 error = ENOSPC; 794 goto out; 795 } 796 ef->progtab[pb].size = shdr[i].sh_size; 797 ef->progtab[pb].sec = i; 798 if (shdr[i].sh_type == SHT_PROGBITS 799#ifdef __amd64__ 800 || shdr[i].sh_type == SHT_AMD64_UNWIND 801#endif 802 ) { 803 error = vn_rdwr(UIO_READ, nd.ni_vp, 804 ef->progtab[pb].addr, 805 shdr[i].sh_size, shdr[i].sh_offset, 806 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 807 NOCRED, &resid, td); 808 if (error) 809 goto out; 810 if (resid != 0){ 811 error = EINVAL; 812 goto out; 813 } 814 /* Initialize the per-cpu or vnet area. */ 815 if (ef->progtab[pb].addr != (void *)mapbase && 816 !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) 817 dpcpu_copy(ef->progtab[pb].addr, 818 shdr[i].sh_size); 819#ifdef VIMAGE 820 else if (ef->progtab[pb].addr != 821 (void *)mapbase && 822 !strcmp(ef->progtab[pb].name, VNET_SETNAME)) 823 vnet_data_copy(ef->progtab[pb].addr, 824 shdr[i].sh_size); 825#endif 826 } else 827 bzero(ef->progtab[pb].addr, shdr[i].sh_size); 828 829 /* Update all symbol values with the offset. */ 830 for (j = 0; j < ef->ddbsymcnt; j++) { 831 es = &ef->ddbsymtab[j]; 832 if (es->st_shndx != i) 833 continue; 834 es->st_value += (Elf_Addr)ef->progtab[pb].addr; 835 } 836 mapbase += shdr[i].sh_size; 837 pb++; 838 break; 839 case SHT_REL: 840 ef->reltab[rl].rel = malloc(shdr[i].sh_size, M_LINKER, 841 M_WAITOK); 842 ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel); 843 ef->reltab[rl].sec = shdr[i].sh_info; 844 error = vn_rdwr(UIO_READ, nd.ni_vp, 845 (void *)ef->reltab[rl].rel, 846 shdr[i].sh_size, shdr[i].sh_offset, 847 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 848 &resid, td); 849 if (error) 850 goto out; 851 if (resid != 0){ 852 error = EINVAL; 853 goto out; 854 } 855 rl++; 856 break; 857 case SHT_RELA: 858 ef->relatab[ra].rela = malloc(shdr[i].sh_size, M_LINKER, 859 M_WAITOK); 860 ef->relatab[ra].nrela = 861 shdr[i].sh_size / sizeof(Elf_Rela); 862 ef->relatab[ra].sec = shdr[i].sh_info; 863 error = vn_rdwr(UIO_READ, nd.ni_vp, 864 (void *)ef->relatab[ra].rela, 865 shdr[i].sh_size, shdr[i].sh_offset, 866 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 867 &resid, td); 868 if (error) 869 goto out; 870 if (resid != 0){ 871 error = EINVAL; 872 goto out; 873 } 874 ra++; 875 break; 876 } 877 } 878 if (pb != ef->nprogtab) { 879 link_elf_error(filename, "lost progbits"); 880 error = ENOEXEC; 881 goto out; 882 } 883 if (rl != ef->nreltab) { 884 link_elf_error(filename, "lost reltab"); 885 error = ENOEXEC; 886 goto out; 887 } 888 if (ra != ef->nrelatab) { 889 link_elf_error(filename, "lost relatab"); 890 error = ENOEXEC; 891 goto out; 892 } 893 if (mapbase != (vm_offset_t)ef->address + mapsize) { 894 printf( 895 "%s: mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n", 896 filename != NULL ? filename : "<none>", 897 (u_long)mapbase, ef->address, (u_long)mapsize, 898 (u_long)(vm_offset_t)ef->address + mapsize); 899 error = ENOMEM; 900 goto out; 901 } 902 903 /* Local intra-module relocations */ 904 error = link_elf_reloc_local(lf); 905 if (error != 0) 906 goto out; 907 908 /* Pull in dependencies */ 909 VOP_UNLOCK(nd.ni_vp, 0); 910 error = linker_load_dependencies(lf); 911 vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY); 912 if (error) 913 goto out; 914 915 /* External relocations */ 916 error = relocate_file(ef); 917 if (error) 918 goto out; 919 920 /* Notify MD code that a module is being loaded. */ 921 error = elf_cpu_load_file(lf); 922 if (error) 923 goto out; 924 925 *result = lf; 926 927out: 928 VOP_UNLOCK(nd.ni_vp, 0); 929 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 930 if (error && lf) 931 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 932 free(hdr, M_LINKER); 933 934 return error; 935} 936 937static void 938link_elf_unload_file(linker_file_t file) 939{ 940 elf_file_t ef = (elf_file_t) file; 941 int i; 942 943 /* Notify MD code that a module is being unloaded. */ 944 elf_cpu_unload_file(file); 945 946 if (ef->progtab) { 947 for (i = 0; i < ef->nprogtab; i++) { 948 if (ef->progtab[i].size == 0) 949 continue; 950 if (ef->progtab[i].name == NULL) 951 continue; 952 if (!strcmp(ef->progtab[i].name, DPCPU_SETNAME)) 953 dpcpu_free(ef->progtab[i].addr, 954 ef->progtab[i].size); 955#ifdef VIMAGE 956 else if (!strcmp(ef->progtab[i].name, VNET_SETNAME)) 957 vnet_data_free(ef->progtab[i].addr, 958 ef->progtab[i].size); 959#endif 960 } 961 } 962 if (ef->preloaded) { 963 free(ef->reltab, M_LINKER); 964 free(ef->relatab, M_LINKER); 965 free(ef->progtab, M_LINKER); 966 free(ef->ctftab, M_LINKER); 967 free(ef->ctfoff, M_LINKER); 968 free(ef->typoff, M_LINKER); 969 if (file->filename != NULL) 970 preload_delete_name(file->filename); 971 /* XXX reclaim module memory? */ 972 return; 973 } 974 975 for (i = 0; i < ef->nreltab; i++) 976 free(ef->reltab[i].rel, M_LINKER); 977 for (i = 0; i < ef->nrelatab; i++) 978 free(ef->relatab[i].rela, M_LINKER); 979 free(ef->reltab, M_LINKER); 980 free(ef->relatab, M_LINKER); 981 free(ef->progtab, M_LINKER); 982 983 if (ef->object) { 984 vm_map_remove(kernel_map, (vm_offset_t) ef->address, 985 (vm_offset_t) ef->address + 986 (ef->object->size << PAGE_SHIFT)); 987 } 988 free(ef->e_shdr, M_LINKER); 989 free(ef->ddbsymtab, M_LINKER); 990 free(ef->ddbstrtab, M_LINKER); 991 free(ef->shstrtab, M_LINKER); 992 free(ef->ctftab, M_LINKER); 993 free(ef->ctfoff, M_LINKER); 994 free(ef->typoff, M_LINKER); 995} 996 997static const char * 998symbol_name(elf_file_t ef, Elf_Size r_info) 999{ 1000 const Elf_Sym *ref; 1001 1002 if (ELF_R_SYM(r_info)) { 1003 ref = ef->ddbsymtab + ELF_R_SYM(r_info); 1004 return ef->ddbstrtab + ref->st_name; 1005 } else 1006 return NULL; 1007} 1008 1009static Elf_Addr 1010findbase(elf_file_t ef, int sec) 1011{ 1012 int i; 1013 Elf_Addr base = 0; 1014 1015 for (i = 0; i < ef->nprogtab; i++) { 1016 if (sec == ef->progtab[i].sec) { 1017 base = (Elf_Addr)ef->progtab[i].addr; 1018 break; 1019 } 1020 } 1021 return base; 1022} 1023 1024static int 1025relocate_file(elf_file_t ef) 1026{ 1027 const Elf_Rel *rellim; 1028 const Elf_Rel *rel; 1029 const Elf_Rela *relalim; 1030 const Elf_Rela *rela; 1031 const char *symname; 1032 const Elf_Sym *sym; 1033 int i; 1034 Elf_Size symidx; 1035 Elf_Addr base; 1036 1037 1038 /* Perform relocations without addend if there are any: */ 1039 for (i = 0; i < ef->nreltab; i++) { 1040 rel = ef->reltab[i].rel; 1041 if (rel == NULL) { 1042 link_elf_error(ef->lf.filename, "lost a reltab!"); 1043 return (ENOEXEC); 1044 } 1045 rellim = rel + ef->reltab[i].nrel; 1046 base = findbase(ef, ef->reltab[i].sec); 1047 if (base == 0) { 1048 link_elf_error(ef->lf.filename, "lost base for reltab"); 1049 return (ENOEXEC); 1050 } 1051 for ( ; rel < rellim; rel++) { 1052 symidx = ELF_R_SYM(rel->r_info); 1053 if (symidx >= ef->ddbsymcnt) 1054 continue; 1055 sym = ef->ddbsymtab + symidx; 1056 /* Local relocs are already done */ 1057 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) 1058 continue; 1059 if (elf_reloc(&ef->lf, base, rel, ELF_RELOC_REL, 1060 elf_obj_lookup)) { 1061 symname = symbol_name(ef, rel->r_info); 1062 printf("link_elf_obj: symbol %s undefined\n", 1063 symname); 1064 return (ENOENT); 1065 } 1066 } 1067 } 1068 1069 /* Perform relocations with addend if there are any: */ 1070 for (i = 0; i < ef->nrelatab; i++) { 1071 rela = ef->relatab[i].rela; 1072 if (rela == NULL) { 1073 link_elf_error(ef->lf.filename, "lost a relatab!"); 1074 return (ENOEXEC); 1075 } 1076 relalim = rela + ef->relatab[i].nrela; 1077 base = findbase(ef, ef->relatab[i].sec); 1078 if (base == 0) { 1079 link_elf_error(ef->lf.filename, 1080 "lost base for relatab"); 1081 return (ENOEXEC); 1082 } 1083 for ( ; rela < relalim; rela++) { 1084 symidx = ELF_R_SYM(rela->r_info); 1085 if (symidx >= ef->ddbsymcnt) 1086 continue; 1087 sym = ef->ddbsymtab + symidx; 1088 /* Local relocs are already done */ 1089 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) 1090 continue; 1091 if (elf_reloc(&ef->lf, base, rela, ELF_RELOC_RELA, 1092 elf_obj_lookup)) { 1093 symname = symbol_name(ef, rela->r_info); 1094 printf("link_elf_obj: symbol %s undefined\n", 1095 symname); 1096 return (ENOENT); 1097 } 1098 } 1099 } 1100 1101 /* 1102 * Only clean SHN_FBSD_CACHED for successful return. If we 1103 * modified symbol table for the object but found an 1104 * unresolved symbol, there is no reason to roll back. 1105 */ 1106 elf_obj_cleanup_globals_cache(ef); 1107 1108 return (0); 1109} 1110 1111static int 1112link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym) 1113{ 1114 elf_file_t ef = (elf_file_t) lf; 1115 const Elf_Sym *symp; 1116 const char *strp; 1117 int i; 1118 1119 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1120 strp = ef->ddbstrtab + symp->st_name; 1121 if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) { 1122 *sym = (c_linker_sym_t) symp; 1123 return 0; 1124 } 1125 } 1126 return ENOENT; 1127} 1128 1129static int 1130link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, 1131 linker_symval_t *symval) 1132{ 1133 elf_file_t ef = (elf_file_t) lf; 1134 const Elf_Sym *es = (const Elf_Sym*) sym; 1135 1136 if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) { 1137 symval->name = ef->ddbstrtab + es->st_name; 1138 symval->value = (caddr_t)es->st_value; 1139 symval->size = es->st_size; 1140 return 0; 1141 } 1142 return ENOENT; 1143} 1144 1145static int 1146link_elf_search_symbol(linker_file_t lf, caddr_t value, 1147 c_linker_sym_t *sym, long *diffp) 1148{ 1149 elf_file_t ef = (elf_file_t) lf; 1150 u_long off = (uintptr_t) (void *) value; 1151 u_long diff = off; 1152 u_long st_value; 1153 const Elf_Sym *es; 1154 const Elf_Sym *best = 0; 1155 int i; 1156 1157 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) { 1158 if (es->st_name == 0) 1159 continue; 1160 st_value = es->st_value; 1161 if (off >= st_value) { 1162 if (off - st_value < diff) { 1163 diff = off - st_value; 1164 best = es; 1165 if (diff == 0) 1166 break; 1167 } else if (off - st_value == diff) { 1168 best = es; 1169 } 1170 } 1171 } 1172 if (best == 0) 1173 *diffp = off; 1174 else 1175 *diffp = diff; 1176 *sym = (c_linker_sym_t) best; 1177 1178 return 0; 1179} 1180 1181/* 1182 * Look up a linker set on an ELF system. 1183 */ 1184static int 1185link_elf_lookup_set(linker_file_t lf, const char *name, 1186 void ***startp, void ***stopp, int *countp) 1187{ 1188 elf_file_t ef = (elf_file_t)lf; 1189 void **start, **stop; 1190 int i, count; 1191 1192 /* Relative to section number */ 1193 for (i = 0; i < ef->nprogtab; i++) { 1194 if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) && 1195 strcmp(ef->progtab[i].name + 4, name) == 0) { 1196 start = (void **)ef->progtab[i].addr; 1197 stop = (void **)((char *)ef->progtab[i].addr + 1198 ef->progtab[i].size); 1199 count = stop - start; 1200 if (startp) 1201 *startp = start; 1202 if (stopp) 1203 *stopp = stop; 1204 if (countp) 1205 *countp = count; 1206 return (0); 1207 } 1208 } 1209 return (ESRCH); 1210} 1211 1212static int 1213link_elf_each_function_name(linker_file_t file, 1214 int (*callback)(const char *, void *), void *opaque) 1215{ 1216 elf_file_t ef = (elf_file_t)file; 1217 const Elf_Sym *symp; 1218 int i, error; 1219 1220 /* Exhaustive search */ 1221 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1222 if (symp->st_value != 0 && 1223 ELF_ST_TYPE(symp->st_info) == STT_FUNC) { 1224 error = callback(ef->ddbstrtab + symp->st_name, opaque); 1225 if (error) 1226 return (error); 1227 } 1228 } 1229 return (0); 1230} 1231 1232static int 1233link_elf_each_function_nameval(linker_file_t file, 1234 linker_function_nameval_callback_t callback, void *opaque) 1235{ 1236 linker_symval_t symval; 1237 elf_file_t ef = (elf_file_t)file; 1238 const Elf_Sym* symp; 1239 int i, error; 1240 1241 /* Exhaustive search */ 1242 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1243 if (symp->st_value != 0 && 1244 ELF_ST_TYPE(symp->st_info) == STT_FUNC) { 1245 error = link_elf_symbol_values(file, (c_linker_sym_t) symp, &symval); 1246 if (error) 1247 return (error); 1248 error = callback(file, i, &symval, opaque); 1249 if (error) 1250 return (error); 1251 } 1252 } 1253 return (0); 1254} 1255 1256static void 1257elf_obj_cleanup_globals_cache(elf_file_t ef) 1258{ 1259 Elf_Sym *sym; 1260 Elf_Size i; 1261 1262 for (i = 0; i < ef->ddbsymcnt; i++) { 1263 sym = ef->ddbsymtab + i; 1264 if (sym->st_shndx == SHN_FBSD_CACHED) { 1265 sym->st_shndx = SHN_UNDEF; 1266 sym->st_value = 0; 1267 } 1268 } 1269} 1270 1271/* 1272 * Symbol lookup function that can be used when the symbol index is known (ie 1273 * in relocations). It uses the symbol index instead of doing a fully fledged 1274 * hash table based lookup when such is valid. For example for local symbols. 1275 * This is not only more efficient, it's also more correct. It's not always 1276 * the case that the symbol can be found through the hash table. 1277 */ 1278static int 1279elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *res) 1280{ 1281 elf_file_t ef = (elf_file_t)lf; 1282 Elf_Sym *sym; 1283 const char *symbol; 1284 Elf_Addr res1; 1285 1286 /* Don't even try to lookup the symbol if the index is bogus. */ 1287 if (symidx >= ef->ddbsymcnt) { 1288 *res = 0; 1289 return (EINVAL); 1290 } 1291 1292 sym = ef->ddbsymtab + symidx; 1293 1294 /* Quick answer if there is a definition included. */ 1295 if (sym->st_shndx != SHN_UNDEF) { 1296 *res = sym->st_value; 1297 return (0); 1298 } 1299 1300 /* If we get here, then it is undefined and needs a lookup. */ 1301 switch (ELF_ST_BIND(sym->st_info)) { 1302 case STB_LOCAL: 1303 /* Local, but undefined? huh? */ 1304 *res = 0; 1305 return (EINVAL); 1306 1307 case STB_GLOBAL: 1308 case STB_WEAK: 1309 /* Relative to Data or Function name */ 1310 symbol = ef->ddbstrtab + sym->st_name; 1311 1312 /* Force a lookup failure if the symbol name is bogus. */ 1313 if (*symbol == 0) { 1314 *res = 0; 1315 return (EINVAL); 1316 } 1317 res1 = (Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps); 1318 1319 /* 1320 * Cache global lookups during module relocation. The failure 1321 * case is particularly expensive for callers, who must scan 1322 * through the entire globals table doing strcmp(). Cache to 1323 * avoid doing such work repeatedly. 1324 * 1325 * After relocation is complete, undefined globals will be 1326 * restored to SHN_UNDEF in elf_obj_cleanup_globals_cache(), 1327 * above. 1328 */ 1329 if (res1 != 0) { 1330 sym->st_shndx = SHN_FBSD_CACHED; 1331 sym->st_value = res1; 1332 *res = res1; 1333 return (0); 1334 } else if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { 1335 sym->st_value = 0; 1336 *res = 0; 1337 return (0); 1338 } 1339 return (EINVAL); 1340 1341 default: 1342 return (EINVAL); 1343 } 1344} 1345 1346static void 1347link_elf_fix_link_set(elf_file_t ef) 1348{ 1349 static const char startn[] = "__start_"; 1350 static const char stopn[] = "__stop_"; 1351 Elf_Sym *sym; 1352 const char *sym_name, *linkset_name; 1353 Elf_Addr startp, stopp; 1354 Elf_Size symidx; 1355 int start, i; 1356 1357 startp = stopp = 0; 1358 for (symidx = 1 /* zero entry is special */; 1359 symidx < ef->ddbsymcnt; symidx++) { 1360 sym = ef->ddbsymtab + symidx; 1361 if (sym->st_shndx != SHN_UNDEF) 1362 continue; 1363 1364 sym_name = ef->ddbstrtab + sym->st_name; 1365 if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) { 1366 start = 1; 1367 linkset_name = sym_name + sizeof(startn) - 1; 1368 } 1369 else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) { 1370 start = 0; 1371 linkset_name = sym_name + sizeof(stopn) - 1; 1372 } 1373 else 1374 continue; 1375 1376 for (i = 0; i < ef->nprogtab; i++) { 1377 if (strcmp(ef->progtab[i].name, linkset_name) == 0) { 1378 startp = (Elf_Addr)ef->progtab[i].addr; 1379 stopp = (Elf_Addr)(startp + ef->progtab[i].size); 1380 break; 1381 } 1382 } 1383 if (i == ef->nprogtab) 1384 continue; 1385 1386 sym->st_value = start ? startp : stopp; 1387 sym->st_shndx = i; 1388 } 1389} 1390 1391static int 1392link_elf_reloc_local(linker_file_t lf) 1393{ 1394 elf_file_t ef = (elf_file_t)lf; 1395 const Elf_Rel *rellim; 1396 const Elf_Rel *rel; 1397 const Elf_Rela *relalim; 1398 const Elf_Rela *rela; 1399 const Elf_Sym *sym; 1400 Elf_Addr base; 1401 int i; 1402 Elf_Size symidx; 1403 1404 link_elf_fix_link_set(ef); 1405 1406 /* Perform relocations without addend if there are any: */ 1407 for (i = 0; i < ef->nreltab; i++) { 1408 rel = ef->reltab[i].rel; 1409 if (rel == NULL) { 1410 link_elf_error(ef->lf.filename, "lost a reltab"); 1411 return (ENOEXEC); 1412 } 1413 rellim = rel + ef->reltab[i].nrel; 1414 base = findbase(ef, ef->reltab[i].sec); 1415 if (base == 0) { 1416 link_elf_error(ef->lf.filename, "lost base for reltab"); 1417 return (ENOEXEC); 1418 } 1419 for ( ; rel < rellim; rel++) { 1420 symidx = ELF_R_SYM(rel->r_info); 1421 if (symidx >= ef->ddbsymcnt) 1422 continue; 1423 sym = ef->ddbsymtab + symidx; 1424 /* Only do local relocs */ 1425 if (ELF_ST_BIND(sym->st_info) != STB_LOCAL) 1426 continue; 1427 elf_reloc_local(lf, base, rel, ELF_RELOC_REL, 1428 elf_obj_lookup); 1429 } 1430 } 1431 1432 /* Perform relocations with addend if there are any: */ 1433 for (i = 0; i < ef->nrelatab; i++) { 1434 rela = ef->relatab[i].rela; 1435 if (rela == NULL) { 1436 link_elf_error(ef->lf.filename, "lost a relatab!"); 1437 return (ENOEXEC); 1438 } 1439 relalim = rela + ef->relatab[i].nrela; 1440 base = findbase(ef, ef->relatab[i].sec); 1441 if (base == 0) { 1442 link_elf_error(ef->lf.filename, "lost base for reltab"); 1443 return (ENOEXEC); 1444 } 1445 for ( ; rela < relalim; rela++) { 1446 symidx = ELF_R_SYM(rela->r_info); 1447 if (symidx >= ef->ddbsymcnt) 1448 continue; 1449 sym = ef->ddbsymtab + symidx; 1450 /* Only do local relocs */ 1451 if (ELF_ST_BIND(sym->st_info) != STB_LOCAL) 1452 continue; 1453 elf_reloc_local(lf, base, rela, ELF_RELOC_RELA, 1454 elf_obj_lookup); 1455 } 1456 } 1457 return (0); 1458} 1459 1460static long 1461link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab) 1462{ 1463 elf_file_t ef = (elf_file_t)lf; 1464 1465 *symtab = ef->ddbsymtab; 1466 1467 if (*symtab == NULL) 1468 return (0); 1469 1470 return (ef->ddbsymcnt); 1471} 1472 1473static long 1474link_elf_strtab_get(linker_file_t lf, caddr_t *strtab) 1475{ 1476 elf_file_t ef = (elf_file_t)lf; 1477 1478 *strtab = ef->ddbstrtab; 1479 1480 if (*strtab == NULL) 1481 return (0); 1482 1483 return (ef->ddbstrcnt); 1484} 1485