sys/kern/link_elf_obj.c

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