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 #include <regex.h> 13 #include <tools/le_byteshift.h> 14 15 static void die(char *fmt, ...); 16 17 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) 18 static Elf32_Ehdr ehdr; 19 static unsigned long reloc_count, reloc_idx; 20 static unsigned long *relocs; 21 static unsigned long reloc16_count, reloc16_idx; 22 static unsigned long *relocs16; 23 24 struct section { 25 Elf32_Shdr shdr; 26 struct section *link; 27 Elf32_Sym *symtab; 28 Elf32_Rel *reltab; 29 char *strtab; 30 }; 31 static struct section *secs; 32 33 enum symtype { 34 S_ABS, 35 S_REL, 36 S_SEG, 37 S_LIN, 38 S_NSYMTYPES 39 }; 40 41 static const char * const sym_regex_kernel[S_NSYMTYPES] = { 42 /* 43 * Following symbols have been audited. There values are constant and do 44 * not change if bzImage is loaded at a different physical address than 45 * the address for which it has been compiled. Don't warn user about 46 * absolute relocations present w.r.t these symbols. 47 */ 48 [S_ABS] = 49 "^(xen_irq_disable_direct_reloc$|" 50 "xen_save_fl_direct_reloc$|" 51 "VDSO|" 52 "__crc_)", 53 54 /* 55 * These symbols are known to be relative, even if the linker marks them 56 * as absolute (typically defined outside any section in the linker script.) 57 */ 58 [S_REL] = 59 "^(__init_(begin|end)|" 60 "__x86_cpu_dev_(start|end)|" 61 "(__parainstructions|__alt_instructions)(|_end)|" 62 "(__iommu_table|__apicdrivers|__smp_locks)(|_end)|" 63 "__(start|end)_pci_.*|" 64 "__(start|end)_builtin_fw|" 65 "__(start|stop)___ksymtab(|_gpl|_unused|_unused_gpl|_gpl_future)|" 66 "__(start|stop)___kcrctab(|_gpl|_unused|_unused_gpl|_gpl_future)|" 67 "__(start|stop)___param|" 68 "__(start|stop)___modver|" 69 "__(start|stop)___bug_table|" 70 "__tracedata_(start|end)|" 71 "__(start|stop)_notes|" 72 "__end_rodata|" 73 "__initramfs_start|" 74 "(jiffies|jiffies_64)|" 75 "_end)$" 76 }; 77 78 79 static const char * const sym_regex_realmode[S_NSYMTYPES] = { 80 /* 81 * These symbols are known to be relative, even if the linker marks them 82 * as absolute (typically defined outside any section in the linker script.) 83 */ 84 [S_REL] = 85 "^pa_", 86 87 /* 88 * These are 16-bit segment symbols when compiling 16-bit code. 89 */ 90 [S_SEG] = 91 "^real_mode_seg$", 92 93 /* 94 * These are offsets belonging to segments, as opposed to linear addresses, 95 * when compiling 16-bit code. 96 */ 97 [S_LIN] = 98 "^pa_", 99 }; 100 101 static const char * const *sym_regex; 102 103 static regex_t sym_regex_c[S_NSYMTYPES]; 104 static int is_reloc(enum symtype type, const char *sym_name) 105 { 106 return sym_regex[type] && 107 !regexec(&sym_regex_c[type], sym_name, 0, NULL, 0); 108 } 109 110 static void regex_init(int use_real_mode) 111 { 112 char errbuf[128]; 113 int err; 114 int i; 115 116 if (use_real_mode) 117 sym_regex = sym_regex_realmode; 118 else 119 sym_regex = sym_regex_kernel; 120 121 for (i = 0; i < S_NSYMTYPES; i++) { 122 if (!sym_regex[i]) 123 continue; 124 125 err = regcomp(&sym_regex_c[i], sym_regex[i], 126 REG_EXTENDED|REG_NOSUB); 127 128 if (err) { 129 regerror(err, &sym_regex_c[i], errbuf, sizeof errbuf); 130 die("%s", errbuf); 131 } 132 } 133 } 134 135 static void die(char *fmt, ...) 136 { 137 va_list ap; 138 va_start(ap, fmt); 139 vfprintf(stderr, fmt, ap); 140 va_end(ap); 141 exit(1); 142 } 143 144 static const char *sym_type(unsigned type) 145 { 146 static const char *type_name[] = { 147 #define SYM_TYPE(X) [X] = #X 148 SYM_TYPE(STT_NOTYPE), 149 SYM_TYPE(STT_OBJECT), 150 SYM_TYPE(STT_FUNC), 151 SYM_TYPE(STT_SECTION), 152 SYM_TYPE(STT_FILE), 153 SYM_TYPE(STT_COMMON), 154 SYM_TYPE(STT_TLS), 155 #undef SYM_TYPE 156 }; 157 const char *name = "unknown sym type name"; 158 if (type < ARRAY_SIZE(type_name)) { 159 name = type_name[type]; 160 } 161 return name; 162 } 163 164 static const char *sym_bind(unsigned bind) 165 { 166 static const char *bind_name[] = { 167 #define SYM_BIND(X) [X] = #X 168 SYM_BIND(STB_LOCAL), 169 SYM_BIND(STB_GLOBAL), 170 SYM_BIND(STB_WEAK), 171 #undef SYM_BIND 172 }; 173 const char *name = "unknown sym bind name"; 174 if (bind < ARRAY_SIZE(bind_name)) { 175 name = bind_name[bind]; 176 } 177 return name; 178 } 179 180 static const char *sym_visibility(unsigned visibility) 181 { 182 static const char *visibility_name[] = { 183 #define SYM_VISIBILITY(X) [X] = #X 184 SYM_VISIBILITY(STV_DEFAULT), 185 SYM_VISIBILITY(STV_INTERNAL), 186 SYM_VISIBILITY(STV_HIDDEN), 187 SYM_VISIBILITY(STV_PROTECTED), 188 #undef SYM_VISIBILITY 189 }; 190 const char *name = "unknown sym visibility name"; 191 if (visibility < ARRAY_SIZE(visibility_name)) { 192 name = visibility_name[visibility]; 193 } 194 return name; 195 } 196 197 static const char *rel_type(unsigned type) 198 { 199 static const char *type_name[] = { 200 #define REL_TYPE(X) [X] = #X 201 REL_TYPE(R_386_NONE), 202 REL_TYPE(R_386_32), 203 REL_TYPE(R_386_PC32), 204 REL_TYPE(R_386_GOT32), 205 REL_TYPE(R_386_PLT32), 206 REL_TYPE(R_386_COPY), 207 REL_TYPE(R_386_GLOB_DAT), 208 REL_TYPE(R_386_JMP_SLOT), 209 REL_TYPE(R_386_RELATIVE), 210 REL_TYPE(R_386_GOTOFF), 211 REL_TYPE(R_386_GOTPC), 212 REL_TYPE(R_386_8), 213 REL_TYPE(R_386_PC8), 214 REL_TYPE(R_386_16), 215 REL_TYPE(R_386_PC16), 216 #undef REL_TYPE 217 }; 218 const char *name = "unknown type rel type name"; 219 if (type < ARRAY_SIZE(type_name) && type_name[type]) { 220 name = type_name[type]; 221 } 222 return name; 223 } 224 225 static const char *sec_name(unsigned shndx) 226 { 227 const char *sec_strtab; 228 const char *name; 229 sec_strtab = secs[ehdr.e_shstrndx].strtab; 230 name = "<noname>"; 231 if (shndx < ehdr.e_shnum) { 232 name = sec_strtab + secs[shndx].shdr.sh_name; 233 } 234 else if (shndx == SHN_ABS) { 235 name = "ABSOLUTE"; 236 } 237 else if (shndx == SHN_COMMON) { 238 name = "COMMON"; 239 } 240 return name; 241 } 242 243 static const char *sym_name(const char *sym_strtab, Elf32_Sym *sym) 244 { 245 const char *name; 246 name = "<noname>"; 247 if (sym->st_name) { 248 name = sym_strtab + sym->st_name; 249 } 250 else { 251 name = sec_name(sym->st_shndx); 252 } 253 return name; 254 } 255 256 257 258 #if BYTE_ORDER == LITTLE_ENDIAN 259 #define le16_to_cpu(val) (val) 260 #define le32_to_cpu(val) (val) 261 #endif 262 #if BYTE_ORDER == BIG_ENDIAN 263 #define le16_to_cpu(val) bswap_16(val) 264 #define le32_to_cpu(val) bswap_32(val) 265 #endif 266 267 static uint16_t elf16_to_cpu(uint16_t val) 268 { 269 return le16_to_cpu(val); 270 } 271 272 static uint32_t elf32_to_cpu(uint32_t val) 273 { 274 return le32_to_cpu(val); 275 } 276 277 static void read_ehdr(FILE *fp) 278 { 279 if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) { 280 die("Cannot read ELF header: %s\n", 281 strerror(errno)); 282 } 283 if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0) { 284 die("No ELF magic\n"); 285 } 286 if (ehdr.e_ident[EI_CLASS] != ELFCLASS32) { 287 die("Not a 32 bit executable\n"); 288 } 289 if (ehdr.e_ident[EI_DATA] != ELFDATA2LSB) { 290 die("Not a LSB ELF executable\n"); 291 } 292 if (ehdr.e_ident[EI_VERSION] != EV_CURRENT) { 293 die("Unknown ELF version\n"); 294 } 295 /* Convert the fields to native endian */ 296 ehdr.e_type = elf16_to_cpu(ehdr.e_type); 297 ehdr.e_machine = elf16_to_cpu(ehdr.e_machine); 298 ehdr.e_version = elf32_to_cpu(ehdr.e_version); 299 ehdr.e_entry = elf32_to_cpu(ehdr.e_entry); 300 ehdr.e_phoff = elf32_to_cpu(ehdr.e_phoff); 301 ehdr.e_shoff = elf32_to_cpu(ehdr.e_shoff); 302 ehdr.e_flags = elf32_to_cpu(ehdr.e_flags); 303 ehdr.e_ehsize = elf16_to_cpu(ehdr.e_ehsize); 304 ehdr.e_phentsize = elf16_to_cpu(ehdr.e_phentsize); 305 ehdr.e_phnum = elf16_to_cpu(ehdr.e_phnum); 306 ehdr.e_shentsize = elf16_to_cpu(ehdr.e_shentsize); 307 ehdr.e_shnum = elf16_to_cpu(ehdr.e_shnum); 308 ehdr.e_shstrndx = elf16_to_cpu(ehdr.e_shstrndx); 309 310 if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN)) { 311 die("Unsupported ELF header type\n"); 312 } 313 if (ehdr.e_machine != EM_386) { 314 die("Not for x86\n"); 315 } 316 if (ehdr.e_version != EV_CURRENT) { 317 die("Unknown ELF version\n"); 318 } 319 if (ehdr.e_ehsize != sizeof(Elf32_Ehdr)) { 320 die("Bad Elf header size\n"); 321 } 322 if (ehdr.e_phentsize != sizeof(Elf32_Phdr)) { 323 die("Bad program header entry\n"); 324 } 325 if (ehdr.e_shentsize != sizeof(Elf32_Shdr)) { 326 die("Bad section header entry\n"); 327 } 328 if (ehdr.e_shstrndx >= ehdr.e_shnum) { 329 die("String table index out of bounds\n"); 330 } 331 } 332 333 static void read_shdrs(FILE *fp) 334 { 335 int i; 336 Elf32_Shdr shdr; 337 338 secs = calloc(ehdr.e_shnum, sizeof(struct section)); 339 if (!secs) { 340 die("Unable to allocate %d section headers\n", 341 ehdr.e_shnum); 342 } 343 if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) { 344 die("Seek to %d failed: %s\n", 345 ehdr.e_shoff, strerror(errno)); 346 } 347 for (i = 0; i < ehdr.e_shnum; i++) { 348 struct section *sec = &secs[i]; 349 if (fread(&shdr, sizeof shdr, 1, fp) != 1) 350 die("Cannot read ELF section headers %d/%d: %s\n", 351 i, ehdr.e_shnum, strerror(errno)); 352 sec->shdr.sh_name = elf32_to_cpu(shdr.sh_name); 353 sec->shdr.sh_type = elf32_to_cpu(shdr.sh_type); 354 sec->shdr.sh_flags = elf32_to_cpu(shdr.sh_flags); 355 sec->shdr.sh_addr = elf32_to_cpu(shdr.sh_addr); 356 sec->shdr.sh_offset = elf32_to_cpu(shdr.sh_offset); 357 sec->shdr.sh_size = elf32_to_cpu(shdr.sh_size); 358 sec->shdr.sh_link = elf32_to_cpu(shdr.sh_link); 359 sec->shdr.sh_info = elf32_to_cpu(shdr.sh_info); 360 sec->shdr.sh_addralign = elf32_to_cpu(shdr.sh_addralign); 361 sec->shdr.sh_entsize = elf32_to_cpu(shdr.sh_entsize); 362 if (sec->shdr.sh_link < ehdr.e_shnum) 363 sec->link = &secs[sec->shdr.sh_link]; 364 } 365 366 } 367 368 static void read_strtabs(FILE *fp) 369 { 370 int i; 371 for (i = 0; i < ehdr.e_shnum; i++) { 372 struct section *sec = &secs[i]; 373 if (sec->shdr.sh_type != SHT_STRTAB) { 374 continue; 375 } 376 sec->strtab = malloc(sec->shdr.sh_size); 377 if (!sec->strtab) { 378 die("malloc of %d bytes for strtab failed\n", 379 sec->shdr.sh_size); 380 } 381 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) { 382 die("Seek to %d failed: %s\n", 383 sec->shdr.sh_offset, strerror(errno)); 384 } 385 if (fread(sec->strtab, 1, sec->shdr.sh_size, fp) 386 != sec->shdr.sh_size) { 387 die("Cannot read symbol table: %s\n", 388 strerror(errno)); 389 } 390 } 391 } 392 393 static void read_symtabs(FILE *fp) 394 { 395 int i,j; 396 for (i = 0; i < ehdr.e_shnum; i++) { 397 struct section *sec = &secs[i]; 398 if (sec->shdr.sh_type != SHT_SYMTAB) { 399 continue; 400 } 401 sec->symtab = malloc(sec->shdr.sh_size); 402 if (!sec->symtab) { 403 die("malloc of %d bytes for symtab failed\n", 404 sec->shdr.sh_size); 405 } 406 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) { 407 die("Seek to %d failed: %s\n", 408 sec->shdr.sh_offset, strerror(errno)); 409 } 410 if (fread(sec->symtab, 1, sec->shdr.sh_size, fp) 411 != sec->shdr.sh_size) { 412 die("Cannot read symbol table: %s\n", 413 strerror(errno)); 414 } 415 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Sym); j++) { 416 Elf32_Sym *sym = &sec->symtab[j]; 417 sym->st_name = elf32_to_cpu(sym->st_name); 418 sym->st_value = elf32_to_cpu(sym->st_value); 419 sym->st_size = elf32_to_cpu(sym->st_size); 420 sym->st_shndx = elf16_to_cpu(sym->st_shndx); 421 } 422 } 423 } 424 425 426 static void read_relocs(FILE *fp) 427 { 428 int i,j; 429 for (i = 0; i < ehdr.e_shnum; i++) { 430 struct section *sec = &secs[i]; 431 if (sec->shdr.sh_type != SHT_REL) { 432 continue; 433 } 434 sec->reltab = malloc(sec->shdr.sh_size); 435 if (!sec->reltab) { 436 die("malloc of %d bytes for relocs failed\n", 437 sec->shdr.sh_size); 438 } 439 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) { 440 die("Seek to %d failed: %s\n", 441 sec->shdr.sh_offset, strerror(errno)); 442 } 443 if (fread(sec->reltab, 1, sec->shdr.sh_size, fp) 444 != sec->shdr.sh_size) { 445 die("Cannot read symbol table: %s\n", 446 strerror(errno)); 447 } 448 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) { 449 Elf32_Rel *rel = &sec->reltab[j]; 450 rel->r_offset = elf32_to_cpu(rel->r_offset); 451 rel->r_info = elf32_to_cpu(rel->r_info); 452 } 453 } 454 } 455 456 457 static void print_absolute_symbols(void) 458 { 459 int i; 460 printf("Absolute symbols\n"); 461 printf(" Num: Value Size Type Bind Visibility Name\n"); 462 for (i = 0; i < ehdr.e_shnum; i++) { 463 struct section *sec = &secs[i]; 464 char *sym_strtab; 465 int j; 466 467 if (sec->shdr.sh_type != SHT_SYMTAB) { 468 continue; 469 } 470 sym_strtab = sec->link->strtab; 471 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Sym); j++) { 472 Elf32_Sym *sym; 473 const char *name; 474 sym = &sec->symtab[j]; 475 name = sym_name(sym_strtab, sym); 476 if (sym->st_shndx != SHN_ABS) { 477 continue; 478 } 479 printf("%5d %08x %5d %10s %10s %12s %s\n", 480 j, sym->st_value, sym->st_size, 481 sym_type(ELF32_ST_TYPE(sym->st_info)), 482 sym_bind(ELF32_ST_BIND(sym->st_info)), 483 sym_visibility(ELF32_ST_VISIBILITY(sym->st_other)), 484 name); 485 } 486 } 487 printf("\n"); 488 } 489 490 static void print_absolute_relocs(void) 491 { 492 int i, printed = 0; 493 494 for (i = 0; i < ehdr.e_shnum; i++) { 495 struct section *sec = &secs[i]; 496 struct section *sec_applies, *sec_symtab; 497 char *sym_strtab; 498 Elf32_Sym *sh_symtab; 499 int j; 500 if (sec->shdr.sh_type != SHT_REL) { 501 continue; 502 } 503 sec_symtab = sec->link; 504 sec_applies = &secs[sec->shdr.sh_info]; 505 if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) { 506 continue; 507 } 508 sh_symtab = sec_symtab->symtab; 509 sym_strtab = sec_symtab->link->strtab; 510 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) { 511 Elf32_Rel *rel; 512 Elf32_Sym *sym; 513 const char *name; 514 rel = &sec->reltab[j]; 515 sym = &sh_symtab[ELF32_R_SYM(rel->r_info)]; 516 name = sym_name(sym_strtab, sym); 517 if (sym->st_shndx != SHN_ABS) { 518 continue; 519 } 520 521 /* Absolute symbols are not relocated if bzImage is 522 * loaded at a non-compiled address. Display a warning 523 * to user at compile time about the absolute 524 * relocations present. 525 * 526 * User need to audit the code to make sure 527 * some symbols which should have been section 528 * relative have not become absolute because of some 529 * linker optimization or wrong programming usage. 530 * 531 * Before warning check if this absolute symbol 532 * relocation is harmless. 533 */ 534 if (is_reloc(S_ABS, name) || is_reloc(S_REL, name)) 535 continue; 536 537 if (!printed) { 538 printf("WARNING: Absolute relocations" 539 " present\n"); 540 printf("Offset Info Type Sym.Value " 541 "Sym.Name\n"); 542 printed = 1; 543 } 544 545 printf("%08x %08x %10s %08x %s\n", 546 rel->r_offset, 547 rel->r_info, 548 rel_type(ELF32_R_TYPE(rel->r_info)), 549 sym->st_value, 550 name); 551 } 552 } 553 554 if (printed) 555 printf("\n"); 556 } 557 558 static void walk_relocs(void (*visit)(Elf32_Rel *rel, Elf32_Sym *sym), 559 int use_real_mode) 560 { 561 int i; 562 /* Walk through the relocations */ 563 for (i = 0; i < ehdr.e_shnum; i++) { 564 char *sym_strtab; 565 Elf32_Sym *sh_symtab; 566 struct section *sec_applies, *sec_symtab; 567 int j; 568 struct section *sec = &secs[i]; 569 570 if (sec->shdr.sh_type != SHT_REL) { 571 continue; 572 } 573 sec_symtab = sec->link; 574 sec_applies = &secs[sec->shdr.sh_info]; 575 if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) { 576 continue; 577 } 578 sh_symtab = sec_symtab->symtab; 579 sym_strtab = sec_symtab->link->strtab; 580 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) { 581 Elf32_Rel *rel; 582 Elf32_Sym *sym; 583 unsigned r_type; 584 const char *symname; 585 int shn_abs; 586 587 rel = &sec->reltab[j]; 588 sym = &sh_symtab[ELF32_R_SYM(rel->r_info)]; 589 r_type = ELF32_R_TYPE(rel->r_info); 590 591 shn_abs = sym->st_shndx == SHN_ABS; 592 593 switch (r_type) { 594 case R_386_NONE: 595 case R_386_PC32: 596 case R_386_PC16: 597 case R_386_PC8: 598 /* 599 * NONE can be ignored and and PC relative 600 * relocations don't need to be adjusted. 601 */ 602 break; 603 604 case R_386_16: 605 symname = sym_name(sym_strtab, sym); 606 if (!use_real_mode) 607 goto bad; 608 if (shn_abs) { 609 if (is_reloc(S_ABS, symname)) 610 break; 611 else if (!is_reloc(S_SEG, symname)) 612 goto bad; 613 } else { 614 if (is_reloc(S_LIN, symname)) 615 goto bad; 616 else 617 break; 618 } 619 visit(rel, sym); 620 break; 621 622 case R_386_32: 623 symname = sym_name(sym_strtab, sym); 624 if (shn_abs) { 625 if (is_reloc(S_ABS, symname)) 626 break; 627 else if (!is_reloc(S_REL, symname)) 628 goto bad; 629 } else { 630 if (use_real_mode && 631 !is_reloc(S_LIN, symname)) 632 break; 633 } 634 visit(rel, sym); 635 break; 636 default: 637 die("Unsupported relocation type: %s (%d)\n", 638 rel_type(r_type), r_type); 639 break; 640 bad: 641 symname = sym_name(sym_strtab, sym); 642 die("Invalid %s %s relocation: %s\n", 643 shn_abs ? "absolute" : "relative", 644 rel_type(r_type), symname); 645 } 646 } 647 } 648 } 649 650 static void count_reloc(Elf32_Rel *rel, Elf32_Sym *sym) 651 { 652 if (ELF32_R_TYPE(rel->r_info) == R_386_16) 653 reloc16_count++; 654 else 655 reloc_count++; 656 } 657 658 static void collect_reloc(Elf32_Rel *rel, Elf32_Sym *sym) 659 { 660 /* Remember the address that needs to be adjusted. */ 661 if (ELF32_R_TYPE(rel->r_info) == R_386_16) 662 relocs16[reloc16_idx++] = rel->r_offset; 663 else 664 relocs[reloc_idx++] = rel->r_offset; 665 } 666 667 static int cmp_relocs(const void *va, const void *vb) 668 { 669 const unsigned long *a, *b; 670 a = va; b = vb; 671 return (*a == *b)? 0 : (*a > *b)? 1 : -1; 672 } 673 674 static int write32(unsigned int v, FILE *f) 675 { 676 unsigned char buf[4]; 677 678 put_unaligned_le32(v, buf); 679 return fwrite(buf, 1, 4, f) == 4 ? 0 : -1; 680 } 681 682 static void emit_relocs(int as_text, int use_real_mode) 683 { 684 int i; 685 /* Count how many relocations I have and allocate space for them. */ 686 reloc_count = 0; 687 walk_relocs(count_reloc, use_real_mode); 688 relocs = malloc(reloc_count * sizeof(relocs[0])); 689 if (!relocs) { 690 die("malloc of %d entries for relocs failed\n", 691 reloc_count); 692 } 693 694 relocs16 = malloc(reloc16_count * sizeof(relocs[0])); 695 if (!relocs16) { 696 die("malloc of %d entries for relocs16 failed\n", 697 reloc16_count); 698 } 699 /* Collect up the relocations */ 700 reloc_idx = 0; 701 walk_relocs(collect_reloc, use_real_mode); 702 703 if (reloc16_count && !use_real_mode) 704 die("Segment relocations found but --realmode not specified\n"); 705 706 /* Order the relocations for more efficient processing */ 707 qsort(relocs, reloc_count, sizeof(relocs[0]), cmp_relocs); 708 qsort(relocs16, reloc16_count, sizeof(relocs16[0]), cmp_relocs); 709 710 /* Print the relocations */ 711 if (as_text) { 712 /* Print the relocations in a form suitable that 713 * gas will like. 714 */ 715 printf(".section \".data.reloc\",\"a\"\n"); 716 printf(".balign 4\n"); 717 if (use_real_mode) { 718 printf("\t.long %lu\n", reloc16_count); 719 for (i = 0; i < reloc16_count; i++) 720 printf("\t.long 0x%08lx\n", relocs16[i]); 721 printf("\t.long %lu\n", reloc_count); 722 for (i = 0; i < reloc_count; i++) { 723 printf("\t.long 0x%08lx\n", relocs[i]); 724 } 725 } else { 726 /* Print a stop */ 727 printf("\t.long 0x%08lx\n", (unsigned long)0); 728 for (i = 0; i < reloc_count; i++) { 729 printf("\t.long 0x%08lx\n", relocs[i]); 730 } 731 } 732 733 printf("\n"); 734 } 735 else { 736 if (use_real_mode) { 737 write32(reloc16_count, stdout); 738 for (i = 0; i < reloc16_count; i++) 739 write32(relocs16[i], stdout); 740 write32(reloc_count, stdout); 741 742 /* Now print each relocation */ 743 for (i = 0; i < reloc_count; i++) 744 write32(relocs[i], stdout); 745 } else { 746 /* Print a stop */ 747 write32(0, stdout); 748 749 /* Now print each relocation */ 750 for (i = 0; i < reloc_count; i++) { 751 write32(relocs[i], stdout); 752 } 753 } 754 } 755 } 756 757 static void usage(void) 758 { 759 die("relocs [--abs-syms|--abs-relocs|--text|--realmode] vmlinux\n"); 760 } 761 762 int main(int argc, char **argv) 763 { 764 int show_absolute_syms, show_absolute_relocs; 765 int as_text, use_real_mode; 766 const char *fname; 767 FILE *fp; 768 int i; 769 770 show_absolute_syms = 0; 771 show_absolute_relocs = 0; 772 as_text = 0; 773 use_real_mode = 0; 774 fname = NULL; 775 for (i = 1; i < argc; i++) { 776 char *arg = argv[i]; 777 if (*arg == '-') { 778 if (strcmp(arg, "--abs-syms") == 0) { 779 show_absolute_syms = 1; 780 continue; 781 } 782 if (strcmp(arg, "--abs-relocs") == 0) { 783 show_absolute_relocs = 1; 784 continue; 785 } 786 if (strcmp(arg, "--text") == 0) { 787 as_text = 1; 788 continue; 789 } 790 if (strcmp(arg, "--realmode") == 0) { 791 use_real_mode = 1; 792 continue; 793 } 794 } 795 else if (!fname) { 796 fname = arg; 797 continue; 798 } 799 usage(); 800 } 801 if (!fname) { 802 usage(); 803 } 804 regex_init(use_real_mode); 805 fp = fopen(fname, "r"); 806 if (!fp) { 807 die("Cannot open %s: %s\n", 808 fname, strerror(errno)); 809 } 810 read_ehdr(fp); 811 read_shdrs(fp); 812 read_strtabs(fp); 813 read_symtabs(fp); 814 read_relocs(fp); 815 if (show_absolute_syms) { 816 print_absolute_symbols(); 817 return 0; 818 } 819 if (show_absolute_relocs) { 820 print_absolute_relocs(); 821 return 0; 822 } 823 emit_relocs(as_text, use_real_mode); 824 return 0; 825 } 826