sys/kern/link_elf_obj.c

   1 /*-
   2  * Copyright (c) 1998 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  * $FreeBSD: src/sys/kern/link_elf.c,v 1.24 1999/12/24 15:33:36 bde Exp $
  28  * $DragonFly: src/sys/kern/link_elf.c,v 1.29 2008/08/01 23:11:16 dillon Exp $
  29  */
  30
  31 #include <sys/param.h>
  32 #include <sys/kernel.h>
  33 #include <sys/systm.h>
  34 #include <sys/malloc.h>
  35 #include <sys/proc.h>
  36 #include <sys/nlookup.h>
  37 #include <sys/fcntl.h>
  38 #include <sys/vnode.h>
  39 #include <sys/linker.h>
  40 #include <machine/elf.h>
  41
  42 #include <vm/vm.h>
  43 #include <vm/vm_param.h>
  44 #include <vm/vm_zone.h>
  45 #include <vm/vm_object.h>
  46 #include <vm/vm_kern.h>
  47 #include <vm/vm_extern.h>
  48 #include <sys/lock.h>
  49 #include <vm/pmap.h>
  50 #include <vm/vm_map.h>
  51
  52 static int      link_elf_obj_preload_file(const char *, linker_file_t *);
  53 static int      link_elf_obj_preload_finish(linker_file_t);
  54 static int      link_elf_obj_load_file(const char *, linker_file_t *);
  55 static int
  56 link_elf_obj_lookup_symbol(linker_file_t, const char *,
  57                        c_linker_sym_t *);
  58 static int      link_elf_obj_symbol_values(linker_file_t, c_linker_sym_t, linker_symval_t *);
  59 static int
  60 link_elf_obj_search_symbol(linker_file_t, caddr_t value,
  61                        c_linker_sym_t * sym, long *diffp);
  62
  63 static void     link_elf_obj_unload_file(linker_file_t);
  64 static int
  65 link_elf_obj_lookup_set(linker_file_t, const char *,
  66                     void ***, void ***, int *);
  67 static void     link_elf_obj_reloc_local(linker_file_t lf);
  68 static int elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *);
  69
  70 static struct linker_class_ops link_elf_obj_class_ops = {
  71         link_elf_obj_load_file,
  72         link_elf_obj_preload_file,
  73 };
  74
  75 static struct linker_file_ops link_elf_obj_file_ops = {
  76         .lookup_symbol = link_elf_obj_lookup_symbol,
  77         .symbol_values = link_elf_obj_symbol_values,
  78         .search_symbol = link_elf_obj_search_symbol,
  79         .preload_finish = link_elf_obj_preload_finish,
  80         .unload = link_elf_obj_unload_file,
  81         .lookup_set = link_elf_obj_lookup_set,
  82 };
  83
  84 typedef struct {
  85         void           *addr;
  86         Elf_Off         size;
  87         int             flags;
  88         int             sec;            /* Original section */
  89         char           *name;
  90 }               Elf_progent;
  91
  92 typedef struct {
  93         Elf_Rel        *rel;
  94         int             nrel;
  95         int             sec;
  96 }               Elf_relent;
  97
  98 typedef struct {
  99         Elf_Rela       *rela;
 100         int             nrela;
 101         int             sec;
 102 }               Elf_relaent;
 103
 104
 105 typedef struct elf_file {
 106         int             preloaded;
 107
 108         caddr_t         address;        /* Relocation address */
 109         size_t          bytes;          /* Chunk size in bytes */
 110         vm_object_t     object;         /* VM object to hold file pages */
 111         Elf_Shdr       *e_shdr;
 112
 113         Elf_progent    *progtab;
 114         int             nprogtab;
 115
 116         Elf_relaent    *relatab;
 117         int             nrelatab;
 118
 119         Elf_relent     *reltab;
 120         int             nreltab;
 121
 122         Elf_Sym        *ddbsymtab;      /* The symbol table we are using */
 123         long            ddbsymcnt;      /* Number of symbols */
 124         caddr_t         ddbstrtab;      /* String table */
 125         long            ddbstrcnt;      /* number of bytes in string table */
 126
 127         caddr_t         shstrtab;       /* Section name string table */
 128         long            shstrcnt;       /* number of bytes in string table */
 129
 130         caddr_t         ctftab;         /* CTF table */
 131         long            ctfcnt;         /* number of bytes in CTF table */
 132         caddr_t         ctfoff;         /* CTF offset table */
 133         caddr_t         typoff;         /* Type offset table */
 134         long            typlen;         /* Number of type entries. */
 135
 136 }              *elf_file_t;
 137
 138 static int      relocate_file(linker_file_t lf);
 139
 140 /*
 141  * The kernel symbol table starts here.
 142  */
 143 extern struct _dynamic _DYNAMIC;
 144
 145 static void
 146 link_elf_obj_init(void *arg)
 147 {
 148 #if ELF_TARG_CLASS == ELFCLASS32
 149         linker_add_class("elf32", NULL, &link_elf_obj_class_ops);
 150 #else
 151         linker_add_class("elf64", NULL, &link_elf_obj_class_ops);
 152 #endif
 153 }
 154
 155 SYSINIT(link_elf, SI_BOOT2_KLD, SI_ORDER_SECOND, link_elf_obj_init, 0);
 156
 157 static void
 158 link_elf_obj_error(const char *file, const char *s)
 159 {
 160         kprintf("kldload: %s: %s\n", file, s);
 161 }
 162
 163 static int
 164 link_elf_obj_preload_file(const char *filename, linker_file_t *result)
 165 {
 166         Elf_Ehdr       *hdr;
 167         Elf_Shdr       *shdr;
 168         Elf_Sym *es;
 169         caddr_t         modptr, baseptr, sizeptr;
 170         char           *type;
 171         elf_file_t      ef;
 172         linker_file_t   lf;
 173         Elf_Addr        off;
 174         int             error, i, j, pb, ra, rl, shstrindex, symstrindex, symtabindex;
 175
 176         /*
 177          * Look to see if we have the module preloaded.
 178          */
 179         modptr = preload_search_by_name(filename);
 180         if (modptr == NULL)
 181                 return ENOENT;
 182
 183         /* It's preloaded, check we can handle it and collect information */
 184         type = (char *)preload_search_info(modptr, MODINFO_TYPE);
 185         baseptr = preload_search_info(modptr, MODINFO_ADDR);
 186         sizeptr = preload_search_info(modptr, MODINFO_SIZE);
 187         hdr = (Elf_Ehdr *) preload_search_info(modptr, MODINFO_METADATA |
 188                                                MODINFOMD_ELFHDR);
 189         shdr = (Elf_Shdr *) preload_search_info(modptr, MODINFO_METADATA |
 190                                                 MODINFOMD_SHDR);
 191         if (type == NULL ||
 192             (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) " obj module") != 0 &&
 193              strcmp(type, "elf obj module") != 0)) {
 194                 return (EFTYPE);
 195         }
 196         if (baseptr == NULL || sizeptr == NULL || hdr == NULL || shdr == NULL)
 197                 return (EINVAL);
 198
 199         ef = kmalloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
 200         ef->preloaded = 1;
 201         ef->address = *(caddr_t *) baseptr;
 202         ef->bytes = 0;
 203         lf = linker_make_file(filename, ef, &link_elf_obj_file_ops);
 204         if (lf == NULL) {
 205                 kfree(ef, M_LINKER);
 206                 return ENOMEM;
 207         }
 208         lf->address = ef->address;
 209         lf->size = *(size_t *) sizeptr;
 210
 211         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
 212             hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
 213             hdr->e_ident[EI_VERSION] != EV_CURRENT ||
 214             hdr->e_version != EV_CURRENT ||
 215             hdr->e_type != ET_REL ||
 216             hdr->e_machine != ELF_TARG_MACH) {
 217                 error = EFTYPE;
 218                 goto out;
 219         }
 220         ef->e_shdr = shdr;
 221
 222         /* Scan the section header for information and table sizing. */
 223         symtabindex = -1;
 224         symstrindex = -1;
 225         for (i = 0; i < hdr->e_shnum; i++) {
 226                 switch (shdr[i].sh_type) {
 227                 case SHT_PROGBITS:
 228                 case SHT_NOBITS:
 229                         ef->nprogtab++;
 230                         break;
 231                 case SHT_SYMTAB:
 232                         symtabindex = i;
 233                         symstrindex = shdr[i].sh_link;
 234                         break;
 235                 case SHT_REL:
 236                         ef->nreltab++;
 237                         break;
 238                 case SHT_RELA:
 239                         ef->nrelatab++;
 240                         break;
 241                 }
 242         }
 243
 244         shstrindex = hdr->e_shstrndx;
 245         if (ef->nprogtab == 0 || symstrindex < 0 ||
 246             symstrindex >= hdr->e_shnum ||
 247             shdr[symstrindex].sh_type != SHT_STRTAB || shstrindex == 0 ||
 248             shstrindex >= hdr->e_shnum ||
 249             shdr[shstrindex].sh_type != SHT_STRTAB) {
 250                 error = ENOEXEC;
 251                 goto out;
 252         }
 253         /* Allocate space for tracking the load chunks */
 254         if (ef->nprogtab != 0)
 255                 ef->progtab = kmalloc(ef->nprogtab * sizeof(*ef->progtab),
 256                                      M_LINKER, M_WAITOK | M_ZERO);
 257         if (ef->nreltab != 0)
 258                 ef->reltab = kmalloc(ef->nreltab * sizeof(*ef->reltab),
 259                                     M_LINKER, M_WAITOK | M_ZERO);
 260         if (ef->nrelatab != 0)
 261                 ef->relatab = kmalloc(ef->nrelatab * sizeof(*ef->relatab),
 262                                      M_LINKER, M_WAITOK | M_ZERO);
 263         if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
 264             (ef->nreltab != 0 && ef->reltab == NULL) ||
 265             (ef->nrelatab != 0 && ef->relatab == NULL)) {
 266                 error = ENOMEM;
 267                 goto out;
 268         }
 269         /* XXX, relocate the sh_addr fields saved by the loader. */
 270         off = 0;
 271         for (i = 0; i < hdr->e_shnum; i++) {
 272                 if (shdr[i].sh_addr != 0 && (off == 0 || shdr[i].sh_addr < off))
 273                         off = shdr[i].sh_addr;
 274         }
 275         for (i = 0; i < hdr->e_shnum; i++) {
 276                 if (shdr[i].sh_addr != 0)
 277                         shdr[i].sh_addr = shdr[i].sh_addr - off +
 278                                 (Elf_Addr) ef->address;
 279         }
 280
 281         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
 282         ef->ddbsymtab = (Elf_Sym *) shdr[symtabindex].sh_addr;
 283         ef->ddbstrcnt = shdr[symstrindex].sh_size;
 284         ef->ddbstrtab = (char *)shdr[symstrindex].sh_addr;
 285         ef->shstrcnt = shdr[shstrindex].sh_size;
 286         ef->shstrtab = (char *)shdr[shstrindex].sh_addr;
 287
 288         /* Now fill out progtab and the relocation tables. */
 289         pb = 0;
 290         rl = 0;
 291         ra = 0;
 292         for (i = 0; i < hdr->e_shnum; i++) {
 293                 switch (shdr[i].sh_type) {
 294                 case SHT_PROGBITS:
 295                 case SHT_NOBITS:
 296                         ef->progtab[pb].addr = (void *)shdr[i].sh_addr;
 297                         if (shdr[i].sh_type == SHT_PROGBITS)
 298                                 ef->progtab[pb].name = "<<PROGBITS>>";
 299                         else
 300                                 ef->progtab[pb].name = "<<NOBITS>>";
 301                         ef->progtab[pb].size = shdr[i].sh_size;
 302                         ef->progtab[pb].sec = i;
 303                         if (ef->shstrtab && shdr[i].sh_name != 0)
 304                                 ef->progtab[pb].name =
 305                                         ef->shstrtab + shdr[i].sh_name;
 306 #if 0
 307                         if (ef->progtab[pb].name != NULL &&
 308                             !strcmp(ef->progtab[pb].name, "set_pcpu")) {
 309                                 void           *dpcpu;
 310
 311                                 dpcpu = dpcpu_alloc(shdr[i].sh_size);
 312                                 if (dpcpu == NULL) {
 313                                         error = ENOSPC;
 314                                         goto out;
 315                                 }
 316                                 memcpy(dpcpu, ef->progtab[pb].addr,
 317                                        ef->progtab[pb].size);
 318                                 dpcpu_copy(dpcpu, shdr[i].sh_size);
 319                                 ef->progtab[pb].addr = dpcpu;
 320 #ifdef VIMAGE
 321                         } else if (ef->progtab[pb].name != NULL &&
 322                                    !strcmp(ef->progtab[pb].name, VNET_SETNAME)) {
 323                                 void           *vnet_data;
 324
 325                                 vnet_data = vnet_data_alloc(shdr[i].sh_size);
 326                                 if (vnet_data == NULL) {
 327                                         error = ENOSPC;
 328                                         goto out;
 329                                 }
 330                                 memcpy(vnet_data, ef->progtab[pb].addr,
 331                                        ef->progtab[pb].size);
 332                                 vnet_data_copy(vnet_data, shdr[i].sh_size);
 333                                 ef->progtab[pb].addr = vnet_data;
 334 #endif
 335                         }
 336 #endif
 337                         /* Update all symbol values with the offset. */
 338                         for (j = 0; j < ef->ddbsymcnt; j++) {
 339                                 es = &ef->ddbsymtab[j];
 340                                 if (es->st_shndx != i)
 341                                         continue;
 342                                 es->st_value += (Elf_Addr) ef->progtab[pb].addr;
 343                         }
 344                         pb++;
 345                         break;
 346                 case SHT_REL:
 347                         ef->reltab[rl].rel = (Elf_Rel *) shdr[i].sh_addr;
 348                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
 349                         ef->reltab[rl].sec = shdr[i].sh_info;
 350                         rl++;
 351                         break;
 352                 case SHT_RELA:
 353                         ef->relatab[ra].rela = (Elf_Rela *) shdr[i].sh_addr;
 354                         ef->relatab[ra].nrela =
 355                                 shdr[i].sh_size / sizeof(Elf_Rela);
 356                         ef->relatab[ra].sec = shdr[i].sh_info;
 357                         ra++;
 358                         break;
 359                 }
 360         }
 361         if (pb != ef->nprogtab)
 362                 panic("lost progbits");
 363         if (rl != ef->nreltab)
 364                 panic("lost reltab");
 365         if (ra != ef->nrelatab)
 366                 panic("lost relatab");
 367
 368         /* Local intra-module relocations */
 369         link_elf_obj_reloc_local(lf);
 370
 371         *result = lf;
 372         return (0);
 373
 374 out:
 375         /* preload not done this way */
 376         linker_file_unload(lf /* , LINKER_UNLOAD_FORCE */ );
 377         return (error);
 378 }
 379
 380 static int
 381 link_elf_obj_preload_finish(linker_file_t lf)
 382 {
 383         int error;
 384
 385         error = relocate_file(lf);
 386
 387         return (error);
 388 }
 389
 390 static int
 391 link_elf_obj_load_file(const char *filename, linker_file_t * result)
 392 {
 393         struct nlookupdata nd;
 394         struct thread  *td = curthread; /* XXX */
 395         struct proc    *p = td->td_proc;
 396         char           *pathname;
 397         struct vnode   *vp;
 398         Elf_Ehdr       *hdr;
 399         Elf_Shdr       *shdr;
 400         Elf_Sym        *es;
 401         int             nbytes, i, j;
 402         vm_offset_t     mapbase;
 403         size_t          mapsize;
 404         int             error = 0;
 405         int             resid;
 406         elf_file_t      ef;
 407         linker_file_t   lf;
 408         int             symtabindex;
 409         int             symstrindex;
 410         int             shstrindex;
 411         int             nsym;
 412         int             pb, rl, ra;
 413         int             alignmask;
 414
 415         /* XXX Hack for firmware loading where p == NULL */
 416         if (p == NULL) {
 417                 p = &proc0;
 418         }
 419
 420         KKASSERT(p != NULL);
 421         if (p->p_ucred == NULL) {
 422                 kprintf("link_elf_obj_load_file: cannot load '%s' from filesystem"
 423                         " this early\n", filename);
 424                 return ENOENT;
 425         }
 426         shdr = NULL;
 427         lf = NULL;
 428         mapsize = 0;
 429         hdr = NULL;
 430         pathname = linker_search_path(filename);
 431         if (pathname == NULL)
 432                 return ENOENT;
 433
 434         error = nlookup_init(&nd, pathname, UIO_SYSSPACE, NLC_FOLLOW | NLC_LOCKVP);
 435         if (error == 0)
 436                 error = vn_open(&nd, NULL, FREAD, 0);
 437         kfree(pathname, M_LINKER);
 438         if (error) {
 439                 nlookup_done(&nd);
 440                 return error;
 441         }
 442         vp = nd.nl_open_vp;
 443         nd.nl_open_vp = NULL;
 444         nlookup_done(&nd);
 445
 446         /*
 447          * Read the elf header from the file.
 448          */
 449         hdr = kmalloc(sizeof(*hdr), M_LINKER, M_WAITOK);
 450         if (hdr == NULL) {
 451                 error = ENOMEM;
 452                 goto out;
 453         }
 454         error = vn_rdwr(UIO_READ, vp, (void *)hdr, sizeof(*hdr), 0,
 455                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
 456         if (error)
 457                 goto out;
 458         if (resid != 0) {
 459                 error = ENOEXEC;
 460                 goto out;
 461         }
 462         if (!IS_ELF(*hdr)) {
 463                 error = ENOEXEC;
 464                 goto out;
 465         }
 466
 467         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
 468             || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
 469                 link_elf_obj_error(filename, "Unsupported file layout");
 470                 error = ENOEXEC;
 471                 goto out;
 472         }
 473         if (hdr->e_ident[EI_VERSION] != EV_CURRENT
 474             || hdr->e_version != EV_CURRENT) {
 475                 link_elf_obj_error(filename, "Unsupported file version");
 476                 error = ENOEXEC;
 477                 goto out;
 478         }
 479         if (hdr->e_type != ET_REL) {
 480                 error = ENOSYS;
 481                 goto out;
 482         }
 483         if (hdr->e_machine != ELF_TARG_MACH) {
 484                 link_elf_obj_error(filename, "Unsupported machine");
 485                 error = ENOEXEC;
 486                 goto out;
 487         }
 488
 489         ef = kmalloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
 490         lf = linker_make_file(filename, ef, &link_elf_obj_file_ops);
 491         if (lf == NULL) {
 492                 kfree(ef, M_LINKER);
 493                 error = ENOMEM;
 494                 goto out;
 495         }
 496         ef->nprogtab = 0;
 497         ef->e_shdr = 0;
 498         ef->nreltab = 0;
 499         ef->nrelatab = 0;
 500
 501         /* Allocate and read in the section header */
 502         nbytes = hdr->e_shnum * hdr->e_shentsize;
 503         if (nbytes == 0 || hdr->e_shoff == 0 ||
 504             hdr->e_shentsize != sizeof(Elf_Shdr)) {
 505                 error = ENOEXEC;
 506                 goto out;
 507         }
 508         shdr = kmalloc(nbytes, M_LINKER, M_WAITOK);
 509         if (shdr == NULL) {
 510                 error = ENOMEM;
 511                 goto out;
 512         }
 513         ef->e_shdr = shdr;
 514         error = vn_rdwr(UIO_READ, vp, (caddr_t) shdr, nbytes, hdr->e_shoff,
 515                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
 516         if (error)
 517                 goto out;
 518         if (resid) {
 519                 error = ENOEXEC;
 520                 goto out;
 521         }
 522         /* Scan the section header for information and table sizing. */
 523         nsym = 0;
 524         symtabindex = -1;
 525         symstrindex = -1;
 526         for (i = 0; i < hdr->e_shnum; i++) {
 527                 switch (shdr[i].sh_type) {
 528                 case SHT_PROGBITS:
 529                 case SHT_NOBITS:
 530                         ef->nprogtab++;
 531                         break;
 532                 case SHT_SYMTAB:
 533                         nsym++;
 534                         symtabindex = i;
 535                         symstrindex = shdr[i].sh_link;
 536                         break;
 537                 case SHT_REL:
 538                         ef->nreltab++;
 539                         break;
 540                 case SHT_RELA:
 541                         ef->nrelatab++;
 542                         break;
 543                 case SHT_STRTAB:
 544                         break;
 545                 }
 546         }
 547         if (ef->nprogtab == 0) {
 548                 link_elf_obj_error(filename, "file has no contents");
 549                 error = ENOEXEC;
 550                 goto out;
 551         }
 552         if (nsym != 1) {
 553                 /* Only allow one symbol table for now */
 554                 link_elf_obj_error(filename, "file has no valid symbol table");
 555                 error = ENOEXEC;
 556                 goto out;
 557         }
 558         if (symstrindex < 0 || symstrindex > hdr->e_shnum ||
 559             shdr[symstrindex].sh_type != SHT_STRTAB) {
 560                 link_elf_obj_error(filename, "file has invalid symbol strings");
 561                 error = ENOEXEC;
 562                 goto out;
 563         }
 564         /* Allocate space for tracking the load chunks */
 565         if (ef->nprogtab != 0)
 566                 ef->progtab = kmalloc(ef->nprogtab * sizeof(*ef->progtab),
 567                                       M_LINKER, M_WAITOK | M_ZERO);
 568         if (ef->nreltab != 0)
 569                 ef->reltab = kmalloc(ef->nreltab * sizeof(*ef->reltab),
 570                                      M_LINKER, M_WAITOK | M_ZERO);
 571         if (ef->nrelatab != 0)
 572                 ef->relatab = kmalloc(ef->nrelatab * sizeof(*ef->relatab),
 573                                       M_LINKER, M_WAITOK | M_ZERO);
 574         if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
 575             (ef->nreltab != 0 && ef->reltab == NULL) ||
 576             (ef->nrelatab != 0 && ef->relatab == NULL)) {
 577                 error = ENOMEM;
 578                 goto out;
 579         }
 580         if (symtabindex == -1)
 581                 panic("lost symbol table index");
 582         /* Allocate space for and load the symbol table */
 583         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
 584         ef->ddbsymtab = kmalloc(shdr[symtabindex].sh_size, M_LINKER, M_WAITOK);
 585         if (ef->ddbsymtab == NULL) {
 586                 error = ENOMEM;
 587                 goto out;
 588         }
 589         error = vn_rdwr(UIO_READ, vp, (void *)ef->ddbsymtab,
 590                         shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset,
 591                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
 592         if (error)
 593                 goto out;
 594         if (resid != 0) {
 595                 error = EINVAL;
 596                 goto out;
 597         }
 598         if (symstrindex == -1)
 599                 panic("lost symbol string index");
 600         /* Allocate space for and load the symbol strings */
 601         ef->ddbstrcnt = shdr[symstrindex].sh_size;
 602         ef->ddbstrtab = kmalloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK);
 603         if (ef->ddbstrtab == NULL) {
 604                 error = ENOMEM;
 605                 goto out;
 606         }
 607         error = vn_rdwr(UIO_READ, vp, ef->ddbstrtab,
 608                         shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset,
 609                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
 610         if (error)
 611                 goto out;
 612         if (resid != 0) {
 613                 error = EINVAL;
 614                 goto out;
 615         }
 616         /* Do we have a string table for the section names?  */
 617         shstrindex = -1;
 618         if (hdr->e_shstrndx != 0 &&
 619             shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) {
 620                 shstrindex = hdr->e_shstrndx;
 621                 ef->shstrcnt = shdr[shstrindex].sh_size;
 622                 ef->shstrtab = kmalloc(shdr[shstrindex].sh_size, M_LINKER,
 623                                        M_WAITOK);
 624                 if (ef->shstrtab == NULL) {
 625                         error = ENOMEM;
 626                         goto out;
 627                 }
 628                 error = vn_rdwr(UIO_READ, vp, ef->shstrtab,
 629                                 shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset,
 630                                 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
 631                 if (error)
 632                         goto out;
 633                 if (resid != 0) {
 634                         error = EINVAL;
 635                         goto out;
 636                 }
 637         }
 638         /* Size up code/data(progbits) and bss(nobits). */
 639         alignmask = 0;
 640         for (i = 0; i < hdr->e_shnum; i++) {
 641                 switch (shdr[i].sh_type) {
 642                 case SHT_PROGBITS:
 643                 case SHT_NOBITS:
 644                         alignmask = shdr[i].sh_addralign - 1;
 645                         mapsize += alignmask;
 646                         mapsize &= ~alignmask;
 647                         mapsize += shdr[i].sh_size;
 648                         break;
 649                 }
 650         }
 651
 652         /*
 653          * We know how much space we need for the text/data/bss/etc. This
 654          * stuff needs to be in a single chunk so that profiling etc can get
 655          * the bounds and gdb can associate offsets with modules
 656          */
 657         ef->object = vm_object_allocate(OBJT_DEFAULT,
 658                                         round_page(mapsize) >> PAGE_SHIFT);
 659         if (ef->object == NULL) {
 660                 error = ENOMEM;
 661                 goto out;
 662         }
 663         vm_object_hold(ef->object);
 664         vm_object_reference_locked(ef->object);
 665         ef->address = (caddr_t) vm_map_min(&kernel_map);
 666         ef->bytes = 0;
 667
 668         /*
 669          * In order to satisfy x86_64's architectural requirements on the
 670          * location of code and data in the kernel's address space, request a
 671          * mapping that is above the kernel.
 672          *
 673          * vkernel64's text+data is outside the managed VM space entirely.
 674          */
 675 #if defined(__amd64__) && defined(_KERNEL_VIRTUAL)
 676         error = vkernel_module_memory_alloc(&mapbase, round_page(mapsize));
 677 #else
 678         mapbase = KERNBASE;
 679         error = vm_map_find(&kernel_map, ef->object, 0, &mapbase,
 680                             round_page(mapsize), PAGE_SIZE,
 681                             TRUE, VM_MAPTYPE_NORMAL,
 682                             VM_PROT_ALL, VM_PROT_ALL, FALSE);
 683         vm_object_drop(ef->object);
 684         if (error) {
 685                 vm_object_deallocate(ef->object);
 686                 ef->object = NULL;
 687                 goto out;
 688         }
 689         /* Wire the pages */
 690         error = vm_map_wire(&kernel_map, mapbase,
 691                             mapbase + round_page(mapsize), 0);
 692 #endif
 693         if (error != KERN_SUCCESS) {
 694                 error = ENOMEM;
 695                 goto out;
 696         }
 697         /* Inform the kld system about the situation */
 698         lf->address = ef->address = (caddr_t) mapbase;
 699         lf->size = round_page(mapsize);
 700         ef->bytes = mapsize;
 701
 702         /*
 703          * Now load code/data(progbits), zero bss(nobits), allocate space for
 704          * and load relocs
 705          */
 706         pb = 0;
 707         rl = 0;
 708         ra = 0;
 709         alignmask = 0;
 710         for (i = 0; i < hdr->e_shnum; i++) {
 711                 switch (shdr[i].sh_type) {
 712                 case SHT_PROGBITS:
 713                 case SHT_NOBITS:
 714                         alignmask = shdr[i].sh_addralign - 1;
 715                         mapbase += alignmask;
 716                         mapbase &= ~alignmask;
 717                         if (ef->shstrtab && shdr[i].sh_name != 0)
 718                                 ef->progtab[pb].name =
 719                                         ef->shstrtab + shdr[i].sh_name;
 720                         else if (shdr[i].sh_type == SHT_PROGBITS)
 721                                 ef->progtab[pb].name = "<<PROGBITS>>";
 722                         else
 723                                 ef->progtab[pb].name = "<<NOBITS>>";
 724 #if 0
 725                         if (ef->progtab[pb].name != NULL &&
 726                             !strcmp(ef->progtab[pb].name, "set_pcpu"))
 727                                 ef->progtab[pb].addr =
 728                                         dpcpu_alloc(shdr[i].sh_size);
 729 #ifdef VIMAGE
 730                         else if (ef->progtab[pb].name != NULL &&
 731                                  !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 732                                 ef->progtab[pb].addr =
 733                                         vnet_data_alloc(shdr[i].sh_size);
 734 #endif
 735                         else
 736 #endif
 737                                 ef->progtab[pb].addr =
 738                                         (void *)(uintptr_t) mapbase;
 739                         if (ef->progtab[pb].addr == NULL) {
 740                                 error = ENOSPC;
 741                                 goto out;
 742                         }
 743                         ef->progtab[pb].size = shdr[i].sh_size;
 744                         ef->progtab[pb].sec = i;
 745                         if (shdr[i].sh_type == SHT_PROGBITS) {
 746                                 error = vn_rdwr(UIO_READ, vp,
 747                                                 ef->progtab[pb].addr,
 748                                                 shdr[i].sh_size, shdr[i].sh_offset,
 749                                                 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred,
 750                                                 &resid);
 751                                 if (error)
 752                                         goto out;
 753                                 if (resid != 0) {
 754                                         error = EINVAL;
 755                                         goto out;
 756                                 }
 757 #if 0
 758                                 /* Initialize the per-cpu or vnet area. */
 759                                 if (ef->progtab[pb].addr != (void *)mapbase &&
 760                                     !strcmp(ef->progtab[pb].name, "set_pcpu"))
 761                                         dpcpu_copy(ef->progtab[pb].addr,
 762                                                    shdr[i].sh_size);
 763 #ifdef VIMAGE
 764                                 else if (ef->progtab[pb].addr !=
 765                                          (void *)mapbase &&
 766                                          !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 767                                         vnet_data_copy(ef->progtab[pb].addr,
 768                                                        shdr[i].sh_size);
 769 #endif
 770 #endif
 771                         } else
 772                                 bzero(ef->progtab[pb].addr, shdr[i].sh_size);
 773
 774                         /* Update all symbol values with the offset. */
 775                         for (j = 0; j < ef->ddbsymcnt; j++) {
 776                                 es = &ef->ddbsymtab[j];
 777                                 if (es->st_shndx != i)
 778                                         continue;
 779                                 es->st_value += (Elf_Addr) ef->progtab[pb].addr;
 780                         }
 781                         mapbase += shdr[i].sh_size;
 782                         pb++;
 783                         break;
 784                 case SHT_REL:
 785                         ef->reltab[rl].rel = kmalloc(shdr[i].sh_size, M_LINKER, M_WAITOK);
 786                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
 787                         ef->reltab[rl].sec = shdr[i].sh_info;
 788                         error = vn_rdwr(UIO_READ, vp,
 789                                         (void *)ef->reltab[rl].rel,
 790                                         shdr[i].sh_size, shdr[i].sh_offset,
 791                                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
 792                         if (error)
 793                                 goto out;
 794                         if (resid != 0) {
 795                                 error = EINVAL;
 796                                 goto out;
 797                         }
 798                         rl++;
 799                         break;
 800                 case SHT_RELA:
 801                         ef->relatab[ra].rela = kmalloc(shdr[i].sh_size, M_LINKER, M_WAITOK);
 802                         ef->relatab[ra].nrela = shdr[i].sh_size / sizeof(Elf_Rela);
 803                         ef->relatab[ra].sec = shdr[i].sh_info;
 804                         error = vn_rdwr(UIO_READ, vp,
 805                                         (void *)ef->relatab[ra].rela,
 806                                         shdr[i].sh_size, shdr[i].sh_offset,
 807                                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
 808                         if (error)
 809                                 goto out;
 810                         if (resid != 0) {
 811                                 error = EINVAL;
 812                                 goto out;
 813                         }
 814                         ra++;
 815                         break;
 816                 }
 817         }
 818         if (pb != ef->nprogtab)
 819                 panic("lost progbits");
 820         if (rl != ef->nreltab)
 821                 panic("lost reltab");
 822         if (ra != ef->nrelatab)
 823                 panic("lost relatab");
 824         if (mapbase != (vm_offset_t) ef->address + mapsize)
 825                 panic("mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n",
 826                       mapbase, ef->address, mapsize,
 827                       (vm_offset_t) ef->address + mapsize);
 828
 829         /* Local intra-module relocations */
 830         link_elf_obj_reloc_local(lf);
 831
 832         /* Pull in dependencies */
 833         error = linker_load_dependencies(lf);
 834         if (error)
 835                 goto out;
 836
 837         /* External relocations */
 838         error = relocate_file(lf);
 839         if (error)
 840                 goto out;
 841
 842         *result = lf;
 843
 844 out:
 845         if (error && lf)
 846                 linker_file_unload(lf /*, LINKER_UNLOAD_FORCE */);
 847         if (hdr)
 848                 kfree(hdr, M_LINKER);
 849         vn_unlock(vp);
 850         vn_close(vp, FREAD);
 851
 852         return error;
 853 }
 854
 855 static void
 856 link_elf_obj_unload_file(linker_file_t file)
 857 {
 858         elf_file_t      ef = file->priv;
 859         int i;
 860
 861         if (ef->progtab) {
 862                 for (i = 0; i < ef->nprogtab; i++) {
 863                         if (ef->progtab[i].size == 0)
 864                                 continue;
 865                         if (ef->progtab[i].name == NULL)
 866                                 continue;
 867 #if 0
 868                         if (!strcmp(ef->progtab[i].name, "set_pcpu"))
 869                                 dpcpu_free(ef->progtab[i].addr,
 870                                     ef->progtab[i].size);
 871 #ifdef VIMAGE
 872                         else if (!strcmp(ef->progtab[i].name, VNET_SETNAME))
 873                                 vnet_data_free(ef->progtab[i].addr,
 874                                     ef->progtab[i].size);
 875 #endif
 876 #endif
 877                 }
 878         }
 879         if (ef->preloaded) {
 880                 if (ef->reltab)
 881                         kfree(ef->reltab, M_LINKER);
 882                 if (ef->relatab)
 883                         kfree(ef->relatab, M_LINKER);
 884                 if (ef->progtab)
 885                         kfree(ef->progtab, M_LINKER);
 886                 if (ef->ctftab)
 887                         kfree(ef->ctftab, M_LINKER);
 888                 if (ef->ctfoff)
 889                         kfree(ef->ctfoff, M_LINKER);
 890                 if (ef->typoff)
 891                         kfree(ef->typoff, M_LINKER);
 892                 if (file->filename != NULL)
 893                         preload_delete_name(file->filename);
 894                 kfree(ef, M_LINKER);
 895                 /* XXX reclaim module memory? */
 896                 return;
 897         }
 898
 899         for (i = 0; i < ef->nreltab; i++)
 900                 if (ef->reltab[i].rel)
 901                         kfree(ef->reltab[i].rel, M_LINKER);
 902         for (i = 0; i < ef->nrelatab; i++)
 903                 if (ef->relatab[i].rela)
 904                         kfree(ef->relatab[i].rela, M_LINKER);
 905         if (ef->reltab)
 906                 kfree(ef->reltab, M_LINKER);
 907         if (ef->relatab)
 908                 kfree(ef->relatab, M_LINKER);
 909         if (ef->progtab)
 910                 kfree(ef->progtab, M_LINKER);
 911
 912         if (ef->object) {
 913 #if defined(__amd64__) && defined(_KERNEL_VIRTUAL)
 914                 vkernel_module_memory_free((vm_offset_t)ef->address, ef->bytes);
 915 #else
 916                 vm_map_remove(&kernel_map, (vm_offset_t) ef->address,
 917                     (vm_offset_t) ef->address +
 918                     (ef->object->size << PAGE_SHIFT));
 919 #endif
 920                 vm_object_deallocate(ef->object);
 921                 ef->object = NULL;
 922         }
 923         if (ef->e_shdr)
 924                 kfree(ef->e_shdr, M_LINKER);
 925         if (ef->ddbsymtab)
 926                 kfree(ef->ddbsymtab, M_LINKER);
 927         if (ef->ddbstrtab)
 928                 kfree(ef->ddbstrtab, M_LINKER);
 929         if (ef->shstrtab)
 930                 kfree(ef->shstrtab, M_LINKER);
 931         if (ef->ctftab)
 932                 kfree(ef->ctftab, M_LINKER);
 933         if (ef->ctfoff)
 934                 kfree(ef->ctfoff, M_LINKER);
 935         if (ef->typoff)
 936                 kfree(ef->typoff, M_LINKER);
 937         kfree(ef, M_LINKER);
 938 }
 939
 940 static const char *
 941 symbol_name(elf_file_t ef, Elf_Size r_info)
 942 {
 943         const Elf_Sym  *ref;
 944
 945         if (ELF_R_SYM(r_info)) {
 946                 ref = ef->ddbsymtab + ELF_R_SYM(r_info);
 947                 return ef->ddbstrtab + ref->st_name;
 948         } else
 949                 return NULL;
 950 }
 951
 952 static Elf_Addr
 953 findbase(elf_file_t ef, int sec)
 954 {
 955         int i;
 956         Elf_Addr base = 0;
 957
 958         for (i = 0; i < ef->nprogtab; i++) {
 959                 if (sec == ef->progtab[i].sec) {
 960                         base = (Elf_Addr)ef->progtab[i].addr;
 961                         break;
 962                 }
 963         }
 964         return base;
 965 }
 966
 967 static int
 968 relocate_file(linker_file_t lf)
 969 {
 970         elf_file_t      ef = lf->priv;
 971         const Elf_Rel *rellim;
 972         const Elf_Rel *rel;
 973         const Elf_Rela *relalim;
 974         const Elf_Rela *rela;
 975         const char *symname;
 976         const Elf_Sym *sym;
 977         int i;
 978         Elf_Size symidx;
 979         Elf_Addr base;
 980
 981         /* Perform relocations without addend if there are any: */
 982         for (i = 0; i < ef->nreltab; i++) {
 983                 rel = ef->reltab[i].rel;
 984                 if (rel == NULL)
 985                         panic("lost a reltab!");
 986                 rellim = rel + ef->reltab[i].nrel;
 987                 base = findbase(ef, ef->reltab[i].sec);
 988                 if (base == 0)
 989                         panic("lost base for reltab");
 990                 for ( ; rel < rellim; rel++) {
 991                         symidx = ELF_R_SYM(rel->r_info);
 992                         if (symidx >= ef->ddbsymcnt)
 993                                 continue;
 994                         sym = ef->ddbsymtab + symidx;
 995                         /* Local relocs are already done */
 996                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
 997                                 continue;
 998                         if (elf_reloc(lf, base, rel, ELF_RELOC_REL,
 999                             elf_obj_lookup)) {
1000                                 symname = symbol_name(ef, rel->r_info);
1001                                 kprintf("link_elf_obj_obj: symbol %s undefined\n",
1002                                     symname);
1003                                 return ENOENT;
1004                         }
1005                 }
1006         }
1007
1008         /* Perform relocations with addend if there are any: */
1009         for (i = 0; i < ef->nrelatab; i++) {
1010                 rela = ef->relatab[i].rela;
1011                 if (rela == NULL)
1012                         panic("lost a relatab!");
1013                 relalim = rela + ef->relatab[i].nrela;
1014                 base = findbase(ef, ef->relatab[i].sec);
1015                 if (base == 0)
1016                         panic("lost base for relatab");
1017                 for ( ; rela < relalim; rela++) {
1018                         symidx = ELF_R_SYM(rela->r_info);
1019                         if (symidx >= ef->ddbsymcnt)
1020                                 continue;
1021                         sym = ef->ddbsymtab + symidx;
1022                         /* Local relocs are already done */
1023                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
1024                                 continue;
1025                         if (elf_reloc(lf, base, rela, ELF_RELOC_RELA,
1026                             elf_obj_lookup)) {
1027                                 symname = symbol_name(ef, rela->r_info);
1028                                 kprintf("link_elf_obj_obj: symbol %s undefined\n",
1029                                     symname);
1030                                 return ENOENT;
1031                         }
1032                 }
1033         }
1034
1035         return 0;
1036 }
1037
1038 static int
1039 link_elf_obj_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym)
1040 {
1041         elf_file_t ef = lf->priv;
1042         const Elf_Sym *symp;
1043         const char *strp;
1044         int i;
1045
1046         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1047                 strp = ef->ddbstrtab + symp->st_name;
1048                 if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) {
1049                         *sym = (c_linker_sym_t) symp;
1050                         return 0;
1051                 }
1052         }
1053         return ENOENT;
1054 }
1055
1056 static int
1057 link_elf_obj_symbol_values(linker_file_t lf, c_linker_sym_t sym,
1058     linker_symval_t *symval)
1059 {
1060         elf_file_t ef = lf->priv;
1061         const Elf_Sym *es = (const Elf_Sym*) sym;
1062
1063         if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
1064                 symval->name = ef->ddbstrtab + es->st_name;
1065                 symval->value = (caddr_t)es->st_value;
1066                 symval->size = es->st_size;
1067                 return 0;
1068         }
1069         return ENOENT;
1070 }
1071
1072 static int
1073 link_elf_obj_search_symbol(linker_file_t lf, caddr_t value,
1074     c_linker_sym_t *sym, long *diffp)
1075 {
1076         elf_file_t ef = lf->priv;
1077         u_long off = (uintptr_t) (void *) value;
1078         u_long diff = off;
1079         u_long st_value;
1080         const Elf_Sym *es;
1081         const Elf_Sym *best = 0;
1082         int i;
1083
1084         for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
1085                 if (es->st_name == 0)
1086                         continue;
1087                 st_value = es->st_value;
1088                 if (off >= st_value) {
1089                         if (off - st_value < diff) {
1090                                 diff = off - st_value;
1091                                 best = es;
1092                                 if (diff == 0)
1093                                         break;
1094                         } else if (off - st_value == diff) {
1095                                 best = es;
1096                         }
1097                 }
1098         }
1099         if (best == 0)
1100                 *diffp = off;
1101         else
1102                 *diffp = diff;
1103         *sym = (c_linker_sym_t) best;
1104
1105         return 0;
1106 }
1107
1108 /*
1109  * Look up a linker set on an ELF system.
1110  */
1111 static int
1112 link_elf_obj_lookup_set(linker_file_t lf, const char *name,
1113     void ***startp, void ***stopp, int *countp)
1114 {
1115         elf_file_t ef = lf->priv;
1116         void **start, **stop;
1117         int i, count;
1118
1119         /* Relative to section number */
1120         for (i = 0; i < ef->nprogtab; i++) {
1121                 if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) &&
1122                     strcmp(ef->progtab[i].name + 4, name) == 0) {
1123                         start  = (void **)ef->progtab[i].addr;
1124                         stop = (void **)((char *)ef->progtab[i].addr +
1125                             ef->progtab[i].size);
1126                         count = stop - start;
1127                         if (startp)
1128                                 *startp = start;
1129                         if (stopp)
1130                                 *stopp = stop;
1131                         if (countp)
1132                                 *countp = count;
1133                         return (0);
1134                 }
1135         }
1136         return (ESRCH);
1137 }
1138
1139 /*
1140  * Symbol lookup function that can be used when the symbol index is known (ie
1141  * in relocations). It uses the symbol index instead of doing a fully fledged
1142  * hash table based lookup when such is valid. For example for local symbols.
1143  * This is not only more efficient, it's also more correct. It's not always
1144  * the case that the symbol can be found through the hash table.
1145  */
1146 static int
1147 elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *result)
1148 {
1149         elf_file_t ef = lf->priv;
1150         const Elf_Sym *sym;
1151         const char *symbol;
1152
1153         /* Don't even try to lookup the symbol if the index is bogus. */
1154         if (symidx >= ef->ddbsymcnt)
1155                 return (ENOENT);
1156
1157         sym = ef->ddbsymtab + symidx;
1158
1159         /* Quick answer if there is a definition included. */
1160         if (sym->st_shndx != SHN_UNDEF) {
1161                 *result = sym->st_value;
1162                 return (0);
1163         }
1164
1165         /* If we get here, then it is undefined and needs a lookup. */
1166         switch (ELF_ST_BIND(sym->st_info)) {
1167         case STB_LOCAL:
1168                 /* Local, but undefined? huh? */
1169                 return (ENOENT);
1170
1171         case STB_GLOBAL:
1172                 /* Relative to Data or Function name */
1173                 symbol = ef->ddbstrtab + sym->st_name;
1174
1175                 /* Force a lookup failure if the symbol name is bogus. */
1176                 if (*symbol == 0)
1177                         return (ENOENT);
1178                 return (linker_file_lookup_symbol(lf, symbol, deps, (caddr_t *)result));
1179
1180         case STB_WEAK:
1181                 kprintf("link_elf_obj_obj: Weak symbols not supported\n");
1182                 return (ENOENT);
1183
1184         default:
1185                 return (ENOENT);
1186         }
1187 }
1188
1189 static void
1190 link_elf_obj_fix_link_set(elf_file_t ef)
1191 {
1192         static const char startn[] = "__start_";
1193         static const char stopn[] = "__stop_";
1194         Elf_Sym *sym;
1195         const char *sym_name, *linkset_name;
1196         Elf_Addr startp, stopp;
1197         Elf_Size symidx;
1198         int start, i;
1199
1200         startp = stopp = 0;
1201         for (symidx = 1 /* zero entry is special */;
1202                 symidx < ef->ddbsymcnt; symidx++) {
1203                 sym = ef->ddbsymtab + symidx;
1204                 if (sym->st_shndx != SHN_UNDEF)
1205                         continue;
1206
1207                 sym_name = ef->ddbstrtab + sym->st_name;
1208                 if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) {
1209                         start = 1;
1210                         linkset_name = sym_name + sizeof(startn) - 1;
1211                 }
1212                 else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) {
1213                         start = 0;
1214                         linkset_name = sym_name + sizeof(stopn) - 1;
1215                 }
1216                 else
1217                         continue;
1218
1219                 for (i = 0; i < ef->nprogtab; i++) {
1220                         if (strcmp(ef->progtab[i].name, linkset_name) == 0) {
1221                                 startp = (Elf_Addr)ef->progtab[i].addr;
1222                                 stopp = (Elf_Addr)(startp + ef->progtab[i].size);
1223                                 break;
1224                         }
1225                 }
1226                 if (i == ef->nprogtab)
1227                         continue;
1228
1229                 sym->st_value = start ? startp : stopp;
1230                 sym->st_shndx = i;
1231         }
1232 }
1233
1234 static void
1235 link_elf_obj_reloc_local(linker_file_t lf)
1236 {
1237         elf_file_t ef = lf->priv;
1238         const Elf_Rel *rellim;
1239         const Elf_Rel *rel;
1240         const Elf_Rela *relalim;
1241         const Elf_Rela *rela;
1242         const Elf_Sym *sym;
1243         Elf_Addr base;
1244         int i;
1245         Elf_Size symidx;
1246
1247         link_elf_obj_fix_link_set(ef);
1248
1249         /* Perform relocations without addend if there are any: */
1250         for (i = 0; i < ef->nreltab; i++) {
1251                 rel = ef->reltab[i].rel;
1252                 if (rel == NULL)
1253                         panic("lost a reltab!");
1254                 rellim = rel + ef->reltab[i].nrel;
1255                 base = findbase(ef, ef->reltab[i].sec);
1256                 if (base == 0)
1257                         panic("lost base for reltab");
1258                 for ( ; rel < rellim; rel++) {
1259                         symidx = ELF_R_SYM(rel->r_info);
1260                         if (symidx >= ef->ddbsymcnt)
1261                                 continue;
1262                         sym = ef->ddbsymtab + symidx;
1263                         /* Only do local relocs */
1264                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1265                                 continue;
1266                         elf_reloc_local(lf, base, rel, ELF_RELOC_REL,
1267                             elf_obj_lookup);
1268                 }
1269         }
1270
1271         /* Perform relocations with addend if there are any: */
1272         for (i = 0; i < ef->nrelatab; i++) {
1273                 rela = ef->relatab[i].rela;
1274                 if (rela == NULL)
1275                         panic("lost a relatab!");
1276                 relalim = rela + ef->relatab[i].nrela;
1277                 base = findbase(ef, ef->relatab[i].sec);
1278                 if (base == 0)
1279                         panic("lost base for relatab");
1280                 for ( ; rela < relalim; rela++) {
1281                         symidx = ELF_R_SYM(rela->r_info);
1282                         if (symidx >= ef->ddbsymcnt)
1283                                 continue;
1284                         sym = ef->ddbsymtab + symidx;
1285                         /* Only do local relocs */
1286                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1287                                 continue;
1288                         elf_reloc_local(lf, base, rela, ELF_RELOC_RELA,
1289                             elf_obj_lookup);
1290                 }
1291         }
1292 }