arch/i386/boot/compressed/relocs.c

   1 #include <stdio.h>
   2 #include <stdarg.h>
   3 #include <stdlib.h>
   4 #include <stdint.h>
   5 #include <string.h>
   6 #include <errno.h>
   7 #include <unistd.h>
   8 #include <elf.h>
   9 #include <byteswap.h>
  10 #define USE_BSD
  11 #include <endian.h>
  12
  13 #define MAX_SHDRS 100
  14 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
  15 static Elf32_Ehdr ehdr;
  16 static Elf32_Shdr shdr[MAX_SHDRS];
  17 static Elf32_Sym  *symtab[MAX_SHDRS];
  18 static Elf32_Rel  *reltab[MAX_SHDRS];
  19 static char *strtab[MAX_SHDRS];
  20 static unsigned long reloc_count, reloc_idx;
  21 static unsigned long *relocs;
  22
  23 /*
  24  * Following symbols have been audited. There values are constant and do
  25  * not change if bzImage is loaded at a different physical address than
  26  * the address for which it has been compiled. Don't warn user about
  27  * absolute relocations present w.r.t these symbols.
  28  */
  29 static const char* safe_abs_relocs[] = {
  30                 "__kernel_vsyscall",
  31                 "__kernel_rt_sigreturn",
  32                 "__kernel_sigreturn",
  33                 "SYSENTER_RETURN",
  34                 "xen_irq_disable_direct_reloc",
  35                 "xen_save_fl_direct_reloc",
  36 };
  37
  38 static int is_safe_abs_reloc(const char* sym_name)
  39 {
  40         int i, array_size;
  41
  42         array_size = sizeof(safe_abs_relocs)/sizeof(char*);
  43
  44         for(i = 0; i < array_size; i++) {
  45                 if (!strcmp(sym_name, safe_abs_relocs[i]))
  46                         /* Match found */
  47                         return 1;
  48         }
  49         if (strncmp(sym_name, "__crc_", 6) == 0)
  50                 return 1;
  51         return 0;
  52 }
  53
  54 static void die(char *fmt, ...)
  55 {
  56         va_list ap;
  57         va_start(ap, fmt);
  58         vfprintf(stderr, fmt, ap);
  59         va_end(ap);
  60         exit(1);
  61 }
  62
  63 static const char *sym_type(unsigned type)
  64 {
  65         static const char *type_name[] = {
  66 #define SYM_TYPE(X) [X] = #X
  67                 SYM_TYPE(STT_NOTYPE),
  68                 SYM_TYPE(STT_OBJECT),
  69                 SYM_TYPE(STT_FUNC),
  70                 SYM_TYPE(STT_SECTION),
  71                 SYM_TYPE(STT_FILE),
  72                 SYM_TYPE(STT_COMMON),
  73                 SYM_TYPE(STT_TLS),
  74 #undef SYM_TYPE
  75         };
  76         const char *name = "unknown sym type name";
  77         if (type < ARRAY_SIZE(type_name)) {
  78                 name = type_name[type];
  79         }
  80         return name;
  81 }
  82
  83 static const char *sym_bind(unsigned bind)
  84 {
  85         static const char *bind_name[] = {
  86 #define SYM_BIND(X) [X] = #X
  87                 SYM_BIND(STB_LOCAL),
  88                 SYM_BIND(STB_GLOBAL),
  89                 SYM_BIND(STB_WEAK),
  90 #undef SYM_BIND
  91         };
  92         const char *name = "unknown sym bind name";
  93         if (bind < ARRAY_SIZE(bind_name)) {
  94                 name = bind_name[bind];
  95         }
  96         return name;
  97 }
  98
  99 static const char *sym_visibility(unsigned visibility)
 100 {
 101         static const char *visibility_name[] = {
 102 #define SYM_VISIBILITY(X) [X] = #X
 103                 SYM_VISIBILITY(STV_DEFAULT),
 104                 SYM_VISIBILITY(STV_INTERNAL),
 105                 SYM_VISIBILITY(STV_HIDDEN),
 106                 SYM_VISIBILITY(STV_PROTECTED),
 107 #undef SYM_VISIBILITY
 108         };
 109         const char *name = "unknown sym visibility name";
 110         if (visibility < ARRAY_SIZE(visibility_name)) {
 111                 name = visibility_name[visibility];
 112         }
 113         return name;
 114 }
 115
 116 static const char *rel_type(unsigned type)
 117 {
 118         static const char *type_name[] = {
 119 #define REL_TYPE(X) [X] = #X
 120                 REL_TYPE(R_386_NONE),
 121                 REL_TYPE(R_386_32),
 122                 REL_TYPE(R_386_PC32),
 123                 REL_TYPE(R_386_GOT32),
 124                 REL_TYPE(R_386_PLT32),
 125                 REL_TYPE(R_386_COPY),
 126                 REL_TYPE(R_386_GLOB_DAT),
 127                 REL_TYPE(R_386_JMP_SLOT),
 128                 REL_TYPE(R_386_RELATIVE),
 129                 REL_TYPE(R_386_GOTOFF),
 130                 REL_TYPE(R_386_GOTPC),
 131 #undef REL_TYPE
 132         };
 133         const char *name = "unknown type rel type name";
 134         if (type < ARRAY_SIZE(type_name)) {
 135                 name = type_name[type];
 136         }
 137         return name;
 138 }
 139
 140 static const char *sec_name(unsigned shndx)
 141 {
 142         const char *sec_strtab;
 143         const char *name;
 144         sec_strtab = strtab[ehdr.e_shstrndx];
 145         name = "<noname>";
 146         if (shndx < ehdr.e_shnum) {
 147                 name = sec_strtab + shdr[shndx].sh_name;
 148         }
 149         else if (shndx == SHN_ABS) {
 150                 name = "ABSOLUTE";
 151         }
 152         else if (shndx == SHN_COMMON) {
 153                 name = "COMMON";
 154         }
 155         return name;
 156 }
 157
 158 static const char *sym_name(const char *sym_strtab, Elf32_Sym *sym)
 159 {
 160         const char *name;
 161         name = "<noname>";
 162         if (sym->st_name) {
 163                 name = sym_strtab + sym->st_name;
 164         }
 165         else {
 166                 name = sec_name(shdr[sym->st_shndx].sh_name);
 167         }
 168         return name;
 169 }
 170
 171
 172
 173 #if BYTE_ORDER == LITTLE_ENDIAN
 174 #define le16_to_cpu(val) (val)
 175 #define le32_to_cpu(val) (val)
 176 #endif
 177 #if BYTE_ORDER == BIG_ENDIAN
 178 #define le16_to_cpu(val) bswap_16(val)
 179 #define le32_to_cpu(val) bswap_32(val)
 180 #endif
 181
 182 static uint16_t elf16_to_cpu(uint16_t val)
 183 {
 184         return le16_to_cpu(val);
 185 }
 186
 187 static uint32_t elf32_to_cpu(uint32_t val)
 188 {
 189         return le32_to_cpu(val);
 190 }
 191
 192 static void read_ehdr(FILE *fp)
 193 {
 194         if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) {
 195                 die("Cannot read ELF header: %s\n",
 196                         strerror(errno));
 197         }
 198         if (memcmp(ehdr.e_ident, ELFMAG, 4) != 0) {
 199                 die("No ELF magic\n");
 200         }
 201         if (ehdr.e_ident[EI_CLASS] != ELFCLASS32) {
 202                 die("Not a 32 bit executable\n");
 203         }
 204         if (ehdr.e_ident[EI_DATA] != ELFDATA2LSB) {
 205                 die("Not a LSB ELF executable\n");
 206         }
 207         if (ehdr.e_ident[EI_VERSION] != EV_CURRENT) {
 208                 die("Unknown ELF version\n");
 209         }
 210         /* Convert the fields to native endian */
 211         ehdr.e_type      = elf16_to_cpu(ehdr.e_type);
 212         ehdr.e_machine   = elf16_to_cpu(ehdr.e_machine);
 213         ehdr.e_version   = elf32_to_cpu(ehdr.e_version);
 214         ehdr.e_entry     = elf32_to_cpu(ehdr.e_entry);
 215         ehdr.e_phoff     = elf32_to_cpu(ehdr.e_phoff);
 216         ehdr.e_shoff     = elf32_to_cpu(ehdr.e_shoff);
 217         ehdr.e_flags     = elf32_to_cpu(ehdr.e_flags);
 218         ehdr.e_ehsize    = elf16_to_cpu(ehdr.e_ehsize);
 219         ehdr.e_phentsize = elf16_to_cpu(ehdr.e_phentsize);
 220         ehdr.e_phnum     = elf16_to_cpu(ehdr.e_phnum);
 221         ehdr.e_shentsize = elf16_to_cpu(ehdr.e_shentsize);
 222         ehdr.e_shnum     = elf16_to_cpu(ehdr.e_shnum);
 223         ehdr.e_shstrndx  = elf16_to_cpu(ehdr.e_shstrndx);
 224
 225         if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN)) {
 226                 die("Unsupported ELF header type\n");
 227         }
 228         if (ehdr.e_machine != EM_386) {
 229                 die("Not for x86\n");
 230         }
 231         if (ehdr.e_version != EV_CURRENT) {
 232                 die("Unknown ELF version\n");
 233         }
 234         if (ehdr.e_ehsize != sizeof(Elf32_Ehdr)) {
 235                 die("Bad Elf header size\n");
 236         }
 237         if (ehdr.e_phentsize != sizeof(Elf32_Phdr)) {
 238                 die("Bad program header entry\n");
 239         }
 240         if (ehdr.e_shentsize != sizeof(Elf32_Shdr)) {
 241                 die("Bad section header entry\n");
 242         }
 243         if (ehdr.e_shstrndx >= ehdr.e_shnum) {
 244                 die("String table index out of bounds\n");
 245         }
 246 }
 247
 248 static void read_shdrs(FILE *fp)
 249 {
 250         int i;
 251         if (ehdr.e_shnum > MAX_SHDRS) {
 252                 die("%d section headers supported: %d\n",
 253                         ehdr.e_shnum, MAX_SHDRS);
 254         }
 255         if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
 256                 die("Seek to %d failed: %s\n",
 257                         ehdr.e_shoff, strerror(errno));
 258         }
 259         if (fread(&shdr, sizeof(shdr[0]), ehdr.e_shnum, fp) != ehdr.e_shnum) {
 260                 die("Cannot read ELF section headers: %s\n",
 261                         strerror(errno));
 262         }
 263         for(i = 0; i < ehdr.e_shnum; i++) {
 264                 shdr[i].sh_name      = elf32_to_cpu(shdr[i].sh_name);
 265                 shdr[i].sh_type      = elf32_to_cpu(shdr[i].sh_type);
 266                 shdr[i].sh_flags     = elf32_to_cpu(shdr[i].sh_flags);
 267                 shdr[i].sh_addr      = elf32_to_cpu(shdr[i].sh_addr);
 268                 shdr[i].sh_offset    = elf32_to_cpu(shdr[i].sh_offset);
 269                 shdr[i].sh_size      = elf32_to_cpu(shdr[i].sh_size);
 270                 shdr[i].sh_link      = elf32_to_cpu(shdr[i].sh_link);
 271                 shdr[i].sh_info      = elf32_to_cpu(shdr[i].sh_info);
 272                 shdr[i].sh_addralign = elf32_to_cpu(shdr[i].sh_addralign);
 273                 shdr[i].sh_entsize   = elf32_to_cpu(shdr[i].sh_entsize);
 274         }
 275
 276 }
 277
 278 static void read_strtabs(FILE *fp)
 279 {
 280         int i;
 281         for(i = 0; i < ehdr.e_shnum; i++) {
 282                 if (shdr[i].sh_type != SHT_STRTAB) {
 283                         continue;
 284                 }
 285                 strtab[i] = malloc(shdr[i].sh_size);
 286                 if (!strtab[i]) {
 287                         die("malloc of %d bytes for strtab failed\n",
 288                                 shdr[i].sh_size);
 289                 }
 290                 if (fseek(fp, shdr[i].sh_offset, SEEK_SET) < 0) {
 291                         die("Seek to %d failed: %s\n",
 292                                 shdr[i].sh_offset, strerror(errno));
 293                 }
 294                 if (fread(strtab[i], 1, shdr[i].sh_size, fp) != shdr[i].sh_size) {
 295                         die("Cannot read symbol table: %s\n",
 296                                 strerror(errno));
 297                 }
 298         }
 299 }
 300
 301 static void read_symtabs(FILE *fp)
 302 {
 303         int i,j;
 304         for(i = 0; i < ehdr.e_shnum; i++) {
 305                 if (shdr[i].sh_type != SHT_SYMTAB) {
 306                         continue;
 307                 }
 308                 symtab[i] = malloc(shdr[i].sh_size);
 309                 if (!symtab[i]) {
 310                         die("malloc of %d bytes for symtab failed\n",
 311                                 shdr[i].sh_size);
 312                 }
 313                 if (fseek(fp, shdr[i].sh_offset, SEEK_SET) < 0) {
 314                         die("Seek to %d failed: %s\n",
 315                                 shdr[i].sh_offset, strerror(errno));
 316                 }
 317                 if (fread(symtab[i], 1, shdr[i].sh_size, fp) != shdr[i].sh_size) {
 318                         die("Cannot read symbol table: %s\n",
 319                                 strerror(errno));
 320                 }
 321                 for(j = 0; j < shdr[i].sh_size/sizeof(symtab[i][0]); j++) {
 322                         symtab[i][j].st_name  = elf32_to_cpu(symtab[i][j].st_name);
 323                         symtab[i][j].st_value = elf32_to_cpu(symtab[i][j].st_value);
 324                         symtab[i][j].st_size  = elf32_to_cpu(symtab[i][j].st_size);
 325                         symtab[i][j].st_shndx = elf16_to_cpu(symtab[i][j].st_shndx);
 326                 }
 327         }
 328 }
 329
 330
 331 static void read_relocs(FILE *fp)
 332 {
 333         int i,j;
 334         for(i = 0; i < ehdr.e_shnum; i++) {
 335                 if (shdr[i].sh_type != SHT_REL) {
 336                         continue;
 337                 }
 338                 reltab[i] = malloc(shdr[i].sh_size);
 339                 if (!reltab[i]) {
 340                         die("malloc of %d bytes for relocs failed\n",
 341                                 shdr[i].sh_size);
 342                 }
 343                 if (fseek(fp, shdr[i].sh_offset, SEEK_SET) < 0) {
 344                         die("Seek to %d failed: %s\n",
 345                                 shdr[i].sh_offset, strerror(errno));
 346                 }
 347                 if (fread(reltab[i], 1, shdr[i].sh_size, fp) != shdr[i].sh_size) {
 348                         die("Cannot read symbol table: %s\n",
 349                                 strerror(errno));
 350                 }
 351                 for(j = 0; j < shdr[i].sh_size/sizeof(reltab[0][0]); j++) {
 352                         reltab[i][j].r_offset = elf32_to_cpu(reltab[i][j].r_offset);
 353                         reltab[i][j].r_info   = elf32_to_cpu(reltab[i][j].r_info);
 354                 }
 355         }
 356 }
 357
 358
 359 static void print_absolute_symbols(void)
 360 {
 361         int i;
 362         printf("Absolute symbols\n");
 363         printf(" Num:    Value Size  Type       Bind        Visibility  Name\n");
 364         for(i = 0; i < ehdr.e_shnum; i++) {
 365                 char *sym_strtab;
 366                 Elf32_Sym *sh_symtab;
 367                 int j;
 368                 if (shdr[i].sh_type != SHT_SYMTAB) {
 369                         continue;
 370                 }
 371                 sh_symtab = symtab[i];
 372                 sym_strtab = strtab[shdr[i].sh_link];
 373                 for(j = 0; j < shdr[i].sh_size/sizeof(symtab[0][0]); j++) {
 374                         Elf32_Sym *sym;
 375                         const char *name;
 376                         sym = &symtab[i][j];
 377                         name = sym_name(sym_strtab, sym);
 378                         if (sym->st_shndx != SHN_ABS) {
 379                                 continue;
 380                         }
 381                         printf("%5d %08x %5d %10s %10s %12s %s\n",
 382                                 j, sym->st_value, sym->st_size,
 383                                 sym_type(ELF32_ST_TYPE(sym->st_info)),
 384                                 sym_bind(ELF32_ST_BIND(sym->st_info)),
 385                                 sym_visibility(ELF32_ST_VISIBILITY(sym->st_other)),
 386                                 name);
 387                 }
 388         }
 389         printf("\n");
 390 }
 391
 392 static void print_absolute_relocs(void)
 393 {
 394         int i, printed = 0;
 395
 396         for(i = 0; i < ehdr.e_shnum; i++) {
 397                 char *sym_strtab;
 398                 Elf32_Sym *sh_symtab;
 399                 unsigned sec_applies, sec_symtab;
 400                 int j;
 401                 if (shdr[i].sh_type != SHT_REL) {
 402                         continue;
 403                 }
 404                 sec_symtab  = shdr[i].sh_link;
 405                 sec_applies = shdr[i].sh_info;
 406                 if (!(shdr[sec_applies].sh_flags & SHF_ALLOC)) {
 407                         continue;
 408                 }
 409                 sh_symtab = symtab[sec_symtab];
 410                 sym_strtab = strtab[shdr[sec_symtab].sh_link];
 411                 for(j = 0; j < shdr[i].sh_size/sizeof(reltab[0][0]); j++) {
 412                         Elf32_Rel *rel;
 413                         Elf32_Sym *sym;
 414                         const char *name;
 415                         rel = &reltab[i][j];
 416                         sym = &sh_symtab[ELF32_R_SYM(rel->r_info)];
 417                         name = sym_name(sym_strtab, sym);
 418                         if (sym->st_shndx != SHN_ABS) {
 419                                 continue;
 420                         }
 421
 422                         /* Absolute symbols are not relocated if bzImage is
 423                          * loaded at a non-compiled address. Display a warning
 424                          * to user at compile time about the absolute
 425                          * relocations present.
 426                          *
 427                          * User need to audit the code to make sure
 428                          * some symbols which should have been section
 429                          * relative have not become absolute because of some
 430                          * linker optimization or wrong programming usage.
 431                          *
 432                          * Before warning check if this absolute symbol
 433                          * relocation is harmless.
 434                          */
 435                         if (is_safe_abs_reloc(name))
 436                                 continue;
 437
 438                         if (!printed) {
 439                                 printf("WARNING: Absolute relocations"
 440                                         " present\n");
 441                                 printf("Offset     Info     Type     Sym.Value "
 442                                         "Sym.Name\n");
 443                                 printed = 1;
 444                         }
 445
 446                         printf("%08x %08x %10s %08x  %s\n",
 447                                 rel->r_offset,
 448                                 rel->r_info,
 449                                 rel_type(ELF32_R_TYPE(rel->r_info)),
 450                                 sym->st_value,
 451                                 name);
 452                 }
 453         }
 454
 455         if (printed)
 456                 printf("\n");
 457 }
 458
 459 static void walk_relocs(void (*visit)(Elf32_Rel *rel, Elf32_Sym *sym))
 460 {
 461         int i;
 462         /* Walk through the relocations */
 463         for(i = 0; i < ehdr.e_shnum; i++) {
 464                 char *sym_strtab;
 465                 Elf32_Sym *sh_symtab;
 466                 unsigned sec_applies, sec_symtab;
 467                 int j;
 468                 if (shdr[i].sh_type != SHT_REL) {
 469                         continue;
 470                 }
 471                 sec_symtab  = shdr[i].sh_link;
 472                 sec_applies = shdr[i].sh_info;
 473                 if (!(shdr[sec_applies].sh_flags & SHF_ALLOC)) {
 474                         continue;
 475                 }
 476                 sh_symtab = symtab[sec_symtab];
 477                 sym_strtab = strtab[shdr[sec_symtab].sh_link];
 478                 for(j = 0; j < shdr[i].sh_size/sizeof(reltab[0][0]); j++) {
 479                         Elf32_Rel *rel;
 480                         Elf32_Sym *sym;
 481                         unsigned r_type;
 482                         rel = &reltab[i][j];
 483                         sym = &sh_symtab[ELF32_R_SYM(rel->r_info)];
 484                         r_type = ELF32_R_TYPE(rel->r_info);
 485                         /* Don't visit relocations to absolute symbols */
 486                         if (sym->st_shndx == SHN_ABS) {
 487                                 continue;
 488                         }
 489                         if (r_type == R_386_PC32) {
 490                                 /* PC relative relocations don't need to be adjusted */
 491                         }
 492                         else if (r_type == R_386_32) {
 493                                 /* Visit relocations that need to be adjusted */
 494                                 visit(rel, sym);
 495                         }
 496                         else {
 497                                 die("Unsupported relocation type: %d\n", r_type);
 498                         }
 499                 }
 500         }
 501 }
 502
 503 static void count_reloc(Elf32_Rel *rel, Elf32_Sym *sym)
 504 {
 505         reloc_count += 1;
 506 }
 507
 508 static void collect_reloc(Elf32_Rel *rel, Elf32_Sym *sym)
 509 {
 510         /* Remember the address that needs to be adjusted. */
 511         relocs[reloc_idx++] = rel->r_offset;
 512 }
 513
 514 static int cmp_relocs(const void *va, const void *vb)
 515 {
 516         const unsigned long *a, *b;
 517         a = va; b = vb;
 518         return (*a == *b)? 0 : (*a > *b)? 1 : -1;
 519 }
 520
 521 static void emit_relocs(int as_text)
 522 {
 523         int i;
 524         /* Count how many relocations I have and allocate space for them. */
 525         reloc_count = 0;
 526         walk_relocs(count_reloc);
 527         relocs = malloc(reloc_count * sizeof(relocs[0]));
 528         if (!relocs) {
 529                 die("malloc of %d entries for relocs failed\n",
 530                         reloc_count);
 531         }
 532         /* Collect up the relocations */
 533         reloc_idx = 0;
 534         walk_relocs(collect_reloc);
 535
 536         /* Order the relocations for more efficient processing */
 537         qsort(relocs, reloc_count, sizeof(relocs[0]), cmp_relocs);
 538
 539         /* Print the relocations */
 540         if (as_text) {
 541                 /* Print the relocations in a form suitable that
 542                  * gas will like.
 543                  */
 544                 printf(".section \".data.reloc\",\"a\"\n");
 545                 printf(".balign 4\n");
 546                 for(i = 0; i < reloc_count; i++) {
 547                         printf("\t .long 0x%08lx\n", relocs[i]);
 548                 }
 549                 printf("\n");
 550         }
 551         else {
 552                 unsigned char buf[4];
 553                 buf[0] = buf[1] = buf[2] = buf[3] = 0;
 554                 /* Print a stop */
 555                 printf("%c%c%c%c", buf[0], buf[1], buf[2], buf[3]);
 556                 /* Now print each relocation */
 557                 for(i = 0; i < reloc_count; i++) {
 558                         buf[0] = (relocs[i] >>  0) & 0xff;
 559                         buf[1] = (relocs[i] >>  8) & 0xff;
 560                         buf[2] = (relocs[i] >> 16) & 0xff;
 561                         buf[3] = (relocs[i] >> 24) & 0xff;
 562                         printf("%c%c%c%c", buf[0], buf[1], buf[2], buf[3]);
 563                 }
 564         }
 565 }
 566
 567 static void usage(void)
 568 {
 569         die("relocs [--abs-syms |--abs-relocs | --text] vmlinux\n");
 570 }
 571
 572 int main(int argc, char **argv)
 573 {
 574         int show_absolute_syms, show_absolute_relocs;
 575         int as_text;
 576         const char *fname;
 577         FILE *fp;
 578         int i;
 579
 580         show_absolute_syms = 0;
 581         show_absolute_relocs = 0;
 582         as_text = 0;
 583         fname = NULL;
 584         for(i = 1; i < argc; i++) {
 585                 char *arg = argv[i];
 586                 if (*arg == '-') {
 587                         if (strcmp(argv[1], "--abs-syms") == 0) {
 588                                 show_absolute_syms = 1;
 589                                 continue;
 590                         }
 591
 592                         if (strcmp(argv[1], "--abs-relocs") == 0) {
 593                                 show_absolute_relocs = 1;
 594                                 continue;
 595                         }
 596                         else if (strcmp(argv[1], "--text") == 0) {
 597                                 as_text = 1;
 598                                 continue;
 599                         }
 600                 }
 601                 else if (!fname) {
 602                         fname = arg;
 603                         continue;
 604                 }
 605                 usage();
 606         }
 607         if (!fname) {
 608                 usage();
 609         }
 610         fp = fopen(fname, "r");
 611         if (!fp) {
 612                 die("Cannot open %s: %s\n",
 613                         fname, strerror(errno));
 614         }
 615         read_ehdr(fp);
 616         read_shdrs(fp);
 617         read_strtabs(fp);
 618         read_symtabs(fp);
 619         read_relocs(fp);
 620         if (show_absolute_syms) {
 621                 print_absolute_symbols();
 622                 return 0;
 623         }
 624         if (show_absolute_relocs) {
 625                 print_absolute_relocs();
 626                 return 0;
 627         }
 628         emit_relocs(as_text);
 629         return 0;
 630 }