1 /* Postprocess module symbol versions 2 * 3 * Copyright 2003 Kai Germaschewski 4 * Copyright 2002-2004 Rusty Russell, IBM Corporation 5 * Copyright 2006-2008 Sam Ravnborg 6 * Based in part on module-init-tools/depmod.c,file2alias 7 * 8 * This software may be used and distributed according to the terms 9 * of the GNU General Public License, incorporated herein by reference. 10 * 11 * Usage: modpost vmlinux module1.o module2.o ... 12 */ 13 14 #define _GNU_SOURCE 15 #include <stdio.h> 16 #include <ctype.h> 17 #include "modpost.h" 18 #include "../../include/linux/license.h" 19 20 /* Are we using CONFIG_MODVERSIONS? */ 21 int modversions = 0; 22 /* Warn about undefined symbols? (do so if we have vmlinux) */ 23 int have_vmlinux = 0; 24 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ 25 static int all_versions = 0; 26 /* If we are modposting external module set to 1 */ 27 static int external_module = 0; 28 /* Warn about section mismatch in vmlinux if set to 1 */ 29 static int vmlinux_section_warnings = 1; 30 /* Only warn about unresolved symbols */ 31 static int warn_unresolved = 0; 32 /* How a symbol is exported */ 33 static int sec_mismatch_count = 0; 34 static int sec_mismatch_verbose = 1; 35 36 enum export { 37 export_plain, export_unused, export_gpl, 38 export_unused_gpl, export_gpl_future, export_unknown 39 }; 40 41 #define PRINTF __attribute__ ((format (printf, 1, 2))) 42 43 PRINTF void fatal(const char *fmt, ...) 44 { 45 va_list arglist; 46 47 fprintf(stderr, "FATAL: "); 48 49 va_start(arglist, fmt); 50 vfprintf(stderr, fmt, arglist); 51 va_end(arglist); 52 53 exit(1); 54 } 55 56 PRINTF void warn(const char *fmt, ...) 57 { 58 va_list arglist; 59 60 fprintf(stderr, "WARNING: "); 61 62 va_start(arglist, fmt); 63 vfprintf(stderr, fmt, arglist); 64 va_end(arglist); 65 } 66 67 PRINTF void merror(const char *fmt, ...) 68 { 69 va_list arglist; 70 71 fprintf(stderr, "ERROR: "); 72 73 va_start(arglist, fmt); 74 vfprintf(stderr, fmt, arglist); 75 va_end(arglist); 76 } 77 78 static int is_vmlinux(const char *modname) 79 { 80 const char *myname; 81 82 myname = strrchr(modname, '/'); 83 if (myname) 84 myname++; 85 else 86 myname = modname; 87 88 return (strcmp(myname, "vmlinux") == 0) || 89 (strcmp(myname, "vmlinux.o") == 0); 90 } 91 92 void *do_nofail(void *ptr, const char *expr) 93 { 94 if (!ptr) 95 fatal("modpost: Memory allocation failure: %s.\n", expr); 96 97 return ptr; 98 } 99 100 /* A list of all modules we processed */ 101 static struct module *modules; 102 103 static struct module *find_module(char *modname) 104 { 105 struct module *mod; 106 107 for (mod = modules; mod; mod = mod->next) 108 if (strcmp(mod->name, modname) == 0) 109 break; 110 return mod; 111 } 112 113 static struct module *new_module(char *modname) 114 { 115 struct module *mod; 116 char *p, *s; 117 118 mod = NOFAIL(malloc(sizeof(*mod))); 119 memset(mod, 0, sizeof(*mod)); 120 p = NOFAIL(strdup(modname)); 121 122 /* strip trailing .o */ 123 s = strrchr(p, '.'); 124 if (s != NULL) 125 if (strcmp(s, ".o") == 0) 126 *s = '\0'; 127 128 /* add to list */ 129 mod->name = p; 130 mod->gpl_compatible = -1; 131 mod->next = modules; 132 modules = mod; 133 134 return mod; 135 } 136 137 /* A hash of all exported symbols, 138 * struct symbol is also used for lists of unresolved symbols */ 139 140 #define SYMBOL_HASH_SIZE 1024 141 142 struct symbol { 143 struct symbol *next; 144 struct module *module; 145 unsigned int crc; 146 int crc_valid; 147 unsigned int weak:1; 148 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */ 149 unsigned int kernel:1; /* 1 if symbol is from kernel 150 * (only for external modules) **/ 151 unsigned int preloaded:1; /* 1 if symbol from Module.symvers */ 152 enum export export; /* Type of export */ 153 char name[0]; 154 }; 155 156 static struct symbol *symbolhash[SYMBOL_HASH_SIZE]; 157 158 /* This is based on the hash agorithm from gdbm, via tdb */ 159 static inline unsigned int tdb_hash(const char *name) 160 { 161 unsigned value; /* Used to compute the hash value. */ 162 unsigned i; /* Used to cycle through random values. */ 163 164 /* Set the initial value from the key size. */ 165 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++) 166 value = (value + (((unsigned char *)name)[i] << (i*5 % 24))); 167 168 return (1103515243 * value + 12345); 169 } 170 171 /** 172 * Allocate a new symbols for use in the hash of exported symbols or 173 * the list of unresolved symbols per module 174 **/ 175 static struct symbol *alloc_symbol(const char *name, unsigned int weak, 176 struct symbol *next) 177 { 178 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1)); 179 180 memset(s, 0, sizeof(*s)); 181 strcpy(s->name, name); 182 s->weak = weak; 183 s->next = next; 184 return s; 185 } 186 187 /* For the hash of exported symbols */ 188 static struct symbol *new_symbol(const char *name, struct module *module, 189 enum export export) 190 { 191 unsigned int hash; 192 struct symbol *new; 193 194 hash = tdb_hash(name) % SYMBOL_HASH_SIZE; 195 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]); 196 new->module = module; 197 new->export = export; 198 return new; 199 } 200 201 static struct symbol *find_symbol(const char *name) 202 { 203 struct symbol *s; 204 205 /* For our purposes, .foo matches foo. PPC64 needs this. */ 206 if (name[0] == '.') 207 name++; 208 209 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) { 210 if (strcmp(s->name, name) == 0) 211 return s; 212 } 213 return NULL; 214 } 215 216 static struct { 217 const char *str; 218 enum export export; 219 } export_list[] = { 220 { .str = "EXPORT_SYMBOL", .export = export_plain }, 221 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused }, 222 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl }, 223 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl }, 224 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future }, 225 { .str = "(unknown)", .export = export_unknown }, 226 }; 227 228 229 static const char *export_str(enum export ex) 230 { 231 return export_list[ex].str; 232 } 233 234 static enum export export_no(const char *s) 235 { 236 int i; 237 238 if (!s) 239 return export_unknown; 240 for (i = 0; export_list[i].export != export_unknown; i++) { 241 if (strcmp(export_list[i].str, s) == 0) 242 return export_list[i].export; 243 } 244 return export_unknown; 245 } 246 247 static enum export export_from_sec(struct elf_info *elf, Elf_Section sec) 248 { 249 if (sec == elf->export_sec) 250 return export_plain; 251 else if (sec == elf->export_unused_sec) 252 return export_unused; 253 else if (sec == elf->export_gpl_sec) 254 return export_gpl; 255 else if (sec == elf->export_unused_gpl_sec) 256 return export_unused_gpl; 257 else if (sec == elf->export_gpl_future_sec) 258 return export_gpl_future; 259 else 260 return export_unknown; 261 } 262 263 /** 264 * Add an exported symbol - it may have already been added without a 265 * CRC, in this case just update the CRC 266 **/ 267 static struct symbol *sym_add_exported(const char *name, struct module *mod, 268 enum export export) 269 { 270 struct symbol *s = find_symbol(name); 271 272 if (!s) { 273 s = new_symbol(name, mod, export); 274 } else { 275 if (!s->preloaded) { 276 warn("%s: '%s' exported twice. Previous export " 277 "was in %s%s\n", mod->name, name, 278 s->module->name, 279 is_vmlinux(s->module->name) ?"":".ko"); 280 } else { 281 /* In case Modules.symvers was out of date */ 282 s->module = mod; 283 } 284 } 285 s->preloaded = 0; 286 s->vmlinux = is_vmlinux(mod->name); 287 s->kernel = 0; 288 s->export = export; 289 return s; 290 } 291 292 static void sym_update_crc(const char *name, struct module *mod, 293 unsigned int crc, enum export export) 294 { 295 struct symbol *s = find_symbol(name); 296 297 if (!s) 298 s = new_symbol(name, mod, export); 299 s->crc = crc; 300 s->crc_valid = 1; 301 } 302 303 void *grab_file(const char *filename, unsigned long *size) 304 { 305 struct stat st; 306 void *map; 307 int fd; 308 309 fd = open(filename, O_RDONLY); 310 if (fd < 0 || fstat(fd, &st) != 0) 311 return NULL; 312 313 *size = st.st_size; 314 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); 315 close(fd); 316 317 if (map == MAP_FAILED) 318 return NULL; 319 return map; 320 } 321 322 /** 323 * Return a copy of the next line in a mmap'ed file. 324 * spaces in the beginning of the line is trimmed away. 325 * Return a pointer to a static buffer. 326 **/ 327 char *get_next_line(unsigned long *pos, void *file, unsigned long size) 328 { 329 static char line[4096]; 330 int skip = 1; 331 size_t len = 0; 332 signed char *p = (signed char *)file + *pos; 333 char *s = line; 334 335 for (; *pos < size ; (*pos)++) { 336 if (skip && isspace(*p)) { 337 p++; 338 continue; 339 } 340 skip = 0; 341 if (*p != '\n' && (*pos < size)) { 342 len++; 343 *s++ = *p++; 344 if (len > 4095) 345 break; /* Too long, stop */ 346 } else { 347 /* End of string */ 348 *s = '\0'; 349 return line; 350 } 351 } 352 /* End of buffer */ 353 return NULL; 354 } 355 356 void release_file(void *file, unsigned long size) 357 { 358 munmap(file, size); 359 } 360 361 static int parse_elf(struct elf_info *info, const char *filename) 362 { 363 unsigned int i; 364 Elf_Ehdr *hdr; 365 Elf_Shdr *sechdrs; 366 Elf_Sym *sym; 367 368 hdr = grab_file(filename, &info->size); 369 if (!hdr) { 370 perror(filename); 371 exit(1); 372 } 373 info->hdr = hdr; 374 if (info->size < sizeof(*hdr)) { 375 /* file too small, assume this is an empty .o file */ 376 return 0; 377 } 378 /* Is this a valid ELF file? */ 379 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) || 380 (hdr->e_ident[EI_MAG1] != ELFMAG1) || 381 (hdr->e_ident[EI_MAG2] != ELFMAG2) || 382 (hdr->e_ident[EI_MAG3] != ELFMAG3)) { 383 /* Not an ELF file - silently ignore it */ 384 return 0; 385 } 386 /* Fix endianness in ELF header */ 387 hdr->e_shoff = TO_NATIVE(hdr->e_shoff); 388 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx); 389 hdr->e_shnum = TO_NATIVE(hdr->e_shnum); 390 hdr->e_machine = TO_NATIVE(hdr->e_machine); 391 hdr->e_type = TO_NATIVE(hdr->e_type); 392 sechdrs = (void *)hdr + hdr->e_shoff; 393 info->sechdrs = sechdrs; 394 395 /* Check if file offset is correct */ 396 if (hdr->e_shoff > info->size) { 397 fatal("section header offset=%lu in file '%s' is bigger than " 398 "filesize=%lu\n", (unsigned long)hdr->e_shoff, 399 filename, info->size); 400 return 0; 401 } 402 403 /* Fix endianness in section headers */ 404 for (i = 0; i < hdr->e_shnum; i++) { 405 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); 406 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset); 407 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size); 408 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link); 409 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name); 410 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info); 411 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr); 412 } 413 /* Find symbol table. */ 414 for (i = 1; i < hdr->e_shnum; i++) { 415 const char *secstrings 416 = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; 417 const char *secname; 418 int nobits = sechdrs[i].sh_type == SHT_NOBITS; 419 420 if (!nobits && sechdrs[i].sh_offset > info->size) { 421 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > " 422 "sizeof(*hrd)=%zu\n", filename, 423 (unsigned long)sechdrs[i].sh_offset, 424 sizeof(*hdr)); 425 return 0; 426 } 427 secname = secstrings + sechdrs[i].sh_name; 428 if (strcmp(secname, ".modinfo") == 0) { 429 if (nobits) 430 fatal("%s has NOBITS .modinfo\n", filename); 431 info->modinfo = (void *)hdr + sechdrs[i].sh_offset; 432 info->modinfo_len = sechdrs[i].sh_size; 433 } else if (strcmp(secname, "__ksymtab") == 0) 434 info->export_sec = i; 435 else if (strcmp(secname, "__ksymtab_unused") == 0) 436 info->export_unused_sec = i; 437 else if (strcmp(secname, "__ksymtab_gpl") == 0) 438 info->export_gpl_sec = i; 439 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0) 440 info->export_unused_gpl_sec = i; 441 else if (strcmp(secname, "__ksymtab_gpl_future") == 0) 442 info->export_gpl_future_sec = i; 443 else if (strcmp(secname, "__markers_strings") == 0) 444 info->markers_strings_sec = i; 445 446 if (sechdrs[i].sh_type != SHT_SYMTAB) 447 continue; 448 449 info->symtab_start = (void *)hdr + sechdrs[i].sh_offset; 450 info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset 451 + sechdrs[i].sh_size; 452 info->strtab = (void *)hdr + 453 sechdrs[sechdrs[i].sh_link].sh_offset; 454 } 455 if (!info->symtab_start) 456 fatal("%s has no symtab?\n", filename); 457 458 /* Fix endianness in symbols */ 459 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) { 460 sym->st_shndx = TO_NATIVE(sym->st_shndx); 461 sym->st_name = TO_NATIVE(sym->st_name); 462 sym->st_value = TO_NATIVE(sym->st_value); 463 sym->st_size = TO_NATIVE(sym->st_size); 464 } 465 return 1; 466 } 467 468 static void parse_elf_finish(struct elf_info *info) 469 { 470 release_file(info->hdr, info->size); 471 } 472 473 static int ignore_undef_symbol(struct elf_info *info, const char *symname) 474 { 475 /* ignore __this_module, it will be resolved shortly */ 476 if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0) 477 return 1; 478 /* ignore global offset table */ 479 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0) 480 return 1; 481 if (info->hdr->e_machine == EM_PPC) 482 /* Special register function linked on all modules during final link of .ko */ 483 if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 || 484 strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 || 485 strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 || 486 strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0) 487 return 1; 488 /* Do not ignore this symbol */ 489 return 0; 490 } 491 492 #define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_" 493 #define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_" 494 495 static void handle_modversions(struct module *mod, struct elf_info *info, 496 Elf_Sym *sym, const char *symname) 497 { 498 unsigned int crc; 499 enum export export = export_from_sec(info, sym->st_shndx); 500 501 switch (sym->st_shndx) { 502 case SHN_COMMON: 503 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name); 504 break; 505 case SHN_ABS: 506 /* CRC'd symbol */ 507 if (memcmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) { 508 crc = (unsigned int) sym->st_value; 509 sym_update_crc(symname + strlen(CRC_PFX), mod, crc, 510 export); 511 } 512 break; 513 case SHN_UNDEF: 514 /* undefined symbol */ 515 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 516 ELF_ST_BIND(sym->st_info) != STB_WEAK) 517 break; 518 if (ignore_undef_symbol(info, symname)) 519 break; 520 /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */ 521 #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER) 522 /* add compatibility with older glibc */ 523 #ifndef STT_SPARC_REGISTER 524 #define STT_SPARC_REGISTER STT_REGISTER 525 #endif 526 if (info->hdr->e_machine == EM_SPARC || 527 info->hdr->e_machine == EM_SPARCV9) { 528 /* Ignore register directives. */ 529 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER) 530 break; 531 if (symname[0] == '.') { 532 char *munged = strdup(symname); 533 munged[0] = '_'; 534 munged[1] = toupper(munged[1]); 535 symname = munged; 536 } 537 } 538 #endif 539 540 if (memcmp(symname, MODULE_SYMBOL_PREFIX, 541 strlen(MODULE_SYMBOL_PREFIX)) == 0) { 542 mod->unres = 543 alloc_symbol(symname + 544 strlen(MODULE_SYMBOL_PREFIX), 545 ELF_ST_BIND(sym->st_info) == STB_WEAK, 546 mod->unres); 547 } 548 break; 549 default: 550 /* All exported symbols */ 551 if (memcmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) { 552 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod, 553 export); 554 } 555 if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0) 556 mod->has_init = 1; 557 if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0) 558 mod->has_cleanup = 1; 559 break; 560 } 561 } 562 563 /** 564 * Parse tag=value strings from .modinfo section 565 **/ 566 static char *next_string(char *string, unsigned long *secsize) 567 { 568 /* Skip non-zero chars */ 569 while (string[0]) { 570 string++; 571 if ((*secsize)-- <= 1) 572 return NULL; 573 } 574 575 /* Skip any zero padding. */ 576 while (!string[0]) { 577 string++; 578 if ((*secsize)-- <= 1) 579 return NULL; 580 } 581 return string; 582 } 583 584 static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len, 585 const char *tag, char *info) 586 { 587 char *p; 588 unsigned int taglen = strlen(tag); 589 unsigned long size = modinfo_len; 590 591 if (info) { 592 size -= info - (char *)modinfo; 593 modinfo = next_string(info, &size); 594 } 595 596 for (p = modinfo; p; p = next_string(p, &size)) { 597 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') 598 return p + taglen + 1; 599 } 600 return NULL; 601 } 602 603 static char *get_modinfo(void *modinfo, unsigned long modinfo_len, 604 const char *tag) 605 606 { 607 return get_next_modinfo(modinfo, modinfo_len, tag, NULL); 608 } 609 610 /** 611 * Test if string s ends in string sub 612 * return 0 if match 613 **/ 614 static int strrcmp(const char *s, const char *sub) 615 { 616 int slen, sublen; 617 618 if (!s || !sub) 619 return 1; 620 621 slen = strlen(s); 622 sublen = strlen(sub); 623 624 if ((slen == 0) || (sublen == 0)) 625 return 1; 626 627 if (sublen > slen) 628 return 1; 629 630 return memcmp(s + slen - sublen, sub, sublen); 631 } 632 633 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) 634 { 635 if (sym) 636 return elf->strtab + sym->st_name; 637 else 638 return "(unknown)"; 639 } 640 641 static const char *sec_name(struct elf_info *elf, int shndx) 642 { 643 Elf_Shdr *sechdrs = elf->sechdrs; 644 return (void *)elf->hdr + 645 elf->sechdrs[elf->hdr->e_shstrndx].sh_offset + 646 sechdrs[shndx].sh_name; 647 } 648 649 static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr) 650 { 651 return (void *)elf->hdr + 652 elf->sechdrs[elf->hdr->e_shstrndx].sh_offset + 653 sechdr->sh_name; 654 } 655 656 /* if sym is empty or point to a string 657 * like ".[0-9]+" then return 1. 658 * This is the optional prefix added by ld to some sections 659 */ 660 static int number_prefix(const char *sym) 661 { 662 if (*sym++ == '\0') 663 return 1; 664 if (*sym != '.') 665 return 0; 666 do { 667 char c = *sym++; 668 if (c < '0' || c > '9') 669 return 0; 670 } while (*sym); 671 return 1; 672 } 673 674 /* The pattern is an array of simple patterns. 675 * "foo" will match an exact string equal to "foo" 676 * "*foo" will match a string that ends with "foo" 677 * "foo*" will match a string that begins with "foo" 678 * "foo$" will match a string equal to "foo" or "foo.1" 679 * where the '1' can be any number including several digits. 680 * The $ syntax is for sections where ld append a dot number 681 * to make section name unique. 682 */ 683 int match(const char *sym, const char * const pat[]) 684 { 685 const char *p; 686 while (*pat) { 687 p = *pat++; 688 const char *endp = p + strlen(p) - 1; 689 690 /* "*foo" */ 691 if (*p == '*') { 692 if (strrcmp(sym, p + 1) == 0) 693 return 1; 694 } 695 /* "foo*" */ 696 else if (*endp == '*') { 697 if (strncmp(sym, p, strlen(p) - 1) == 0) 698 return 1; 699 } 700 /* "foo$" */ 701 else if (*endp == '$') { 702 if (strncmp(sym, p, strlen(p) - 1) == 0) { 703 if (number_prefix(sym + strlen(p) - 1)) 704 return 1; 705 } 706 } 707 /* no wildcards */ 708 else { 709 if (strcmp(p, sym) == 0) 710 return 1; 711 } 712 } 713 /* no match */ 714 return 0; 715 } 716 717 /* sections that we do not want to do full section mismatch check on */ 718 static const char *section_white_list[] = 719 { ".debug*", ".stab*", ".note*", ".got*", ".toc*", NULL }; 720 721 /* 722 * Is this section one we do not want to check? 723 * This is often debug sections. 724 * If we are going to check this section then 725 * test if section name ends with a dot and a number. 726 * This is used to find sections where the linker have 727 * appended a dot-number to make the name unique. 728 * The cause of this is often a section specified in assembler 729 * without "ax" / "aw" and the same section used in .c 730 * code where gcc add these. 731 */ 732 static int check_section(const char *modname, const char *sec) 733 { 734 const char *e = sec + strlen(sec) - 1; 735 if (match(sec, section_white_list)) 736 return 1; 737 738 if (*e && isdigit(*e)) { 739 /* consume all digits */ 740 while (*e && e != sec && isdigit(*e)) 741 e--; 742 if (*e == '.' && !strstr(sec, ".linkonce")) { 743 warn("%s (%s): unexpected section name.\n" 744 "The (.[number]+) following section name are " 745 "ld generated and not expected.\n" 746 "Did you forget to use \"ax\"/\"aw\" " 747 "in a .S file?\n" 748 "Note that for example <linux/init.h> contains\n" 749 "section definitions for use in .S files.\n\n", 750 modname, sec); 751 } 752 } 753 return 0; 754 } 755 756 757 758 #define ALL_INIT_DATA_SECTIONS \ 759 ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$" 760 #define ALL_EXIT_DATA_SECTIONS \ 761 ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$" 762 763 #define ALL_INIT_TEXT_SECTIONS \ 764 ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$" 765 #define ALL_EXIT_TEXT_SECTIONS \ 766 ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$" 767 768 #define ALL_INIT_SECTIONS ALL_INIT_DATA_SECTIONS, ALL_INIT_TEXT_SECTIONS 769 #define ALL_EXIT_SECTIONS ALL_EXIT_DATA_SECTIONS, ALL_EXIT_TEXT_SECTIONS 770 771 #define DATA_SECTIONS ".data$", ".data.rel$" 772 #define TEXT_SECTIONS ".text$" 773 774 #define INIT_SECTIONS ".init.data$", ".init.text$" 775 #define DEV_INIT_SECTIONS ".devinit.data$", ".devinit.text$" 776 #define CPU_INIT_SECTIONS ".cpuinit.data$", ".cpuinit.text$" 777 #define MEM_INIT_SECTIONS ".meminit.data$", ".meminit.text$" 778 779 #define EXIT_SECTIONS ".exit.data$", ".exit.text$" 780 #define DEV_EXIT_SECTIONS ".devexit.data$", ".devexit.text$" 781 #define CPU_EXIT_SECTIONS ".cpuexit.data$", ".cpuexit.text$" 782 #define MEM_EXIT_SECTIONS ".memexit.data$", ".memexit.text$" 783 784 /* init data sections */ 785 static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL }; 786 787 /* all init sections */ 788 static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL }; 789 790 /* All init and exit sections (code + data) */ 791 static const char *init_exit_sections[] = 792 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }; 793 794 /* data section */ 795 static const char *data_sections[] = { DATA_SECTIONS, NULL }; 796 797 /* sections that may refer to an init/exit section with no warning */ 798 static const char *initref_sections[] = 799 { 800 ".text.init.refok*", 801 ".exit.text.refok*", 802 ".data.init.refok*", 803 NULL 804 }; 805 806 807 /* symbols in .data that may refer to init/exit sections */ 808 static const char *symbol_white_list[] = 809 { 810 "*driver", 811 "*_template", /* scsi uses *_template a lot */ 812 "*_timer", /* arm uses ops structures named _timer a lot */ 813 "*_sht", /* scsi also used *_sht to some extent */ 814 "*_ops", 815 "*_probe", 816 "*_probe_one", 817 "*_console", 818 NULL 819 }; 820 821 static const char *head_sections[] = { ".head.text*", NULL }; 822 static const char *linker_symbols[] = 823 { "__init_begin", "_sinittext", "_einittext", NULL }; 824 825 enum mismatch { 826 NO_MISMATCH, 827 TEXT_TO_INIT, 828 DATA_TO_INIT, 829 TEXT_TO_EXIT, 830 DATA_TO_EXIT, 831 XXXINIT_TO_INIT, 832 XXXEXIT_TO_EXIT, 833 INIT_TO_EXIT, 834 EXIT_TO_INIT, 835 EXPORT_TO_INIT_EXIT, 836 }; 837 838 struct sectioncheck { 839 const char *fromsec[20]; 840 const char *tosec[20]; 841 enum mismatch mismatch; 842 }; 843 844 const struct sectioncheck sectioncheck[] = { 845 /* Do not reference init/exit code/data from 846 * normal code and data 847 */ 848 { 849 .fromsec = { TEXT_SECTIONS, NULL }, 850 .tosec = { ALL_INIT_SECTIONS, NULL }, 851 .mismatch = TEXT_TO_INIT, 852 }, 853 { 854 .fromsec = { DATA_SECTIONS, NULL }, 855 .tosec = { ALL_INIT_SECTIONS, NULL }, 856 .mismatch = DATA_TO_INIT, 857 }, 858 { 859 .fromsec = { TEXT_SECTIONS, NULL }, 860 .tosec = { ALL_EXIT_SECTIONS, NULL }, 861 .mismatch = TEXT_TO_EXIT, 862 }, 863 { 864 .fromsec = { DATA_SECTIONS, NULL }, 865 .tosec = { ALL_EXIT_SECTIONS, NULL }, 866 .mismatch = DATA_TO_EXIT, 867 }, 868 /* Do not reference init code/data from devinit/cpuinit/meminit code/data */ 869 { 870 .fromsec = { DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, MEM_INIT_SECTIONS, NULL }, 871 .tosec = { INIT_SECTIONS, NULL }, 872 .mismatch = XXXINIT_TO_INIT, 873 }, 874 /* Do not reference exit code/data from devexit/cpuexit/memexit code/data */ 875 { 876 .fromsec = { DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, MEM_EXIT_SECTIONS, NULL }, 877 .tosec = { EXIT_SECTIONS, NULL }, 878 .mismatch = XXXEXIT_TO_EXIT, 879 }, 880 /* Do not use exit code/data from init code */ 881 { 882 .fromsec = { ALL_INIT_SECTIONS, NULL }, 883 .tosec = { ALL_EXIT_SECTIONS, NULL }, 884 .mismatch = INIT_TO_EXIT, 885 }, 886 /* Do not use init code/data from exit code */ 887 { 888 .fromsec = { ALL_EXIT_SECTIONS, NULL }, 889 .tosec = { ALL_INIT_SECTIONS, NULL }, 890 .mismatch = EXIT_TO_INIT, 891 }, 892 /* Do not export init/exit functions or data */ 893 { 894 .fromsec = { "__ksymtab*", NULL }, 895 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL }, 896 .mismatch = EXPORT_TO_INIT_EXIT 897 } 898 }; 899 900 static int section_mismatch(const char *fromsec, const char *tosec) 901 { 902 int i; 903 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck); 904 const struct sectioncheck *check = §ioncheck[0]; 905 906 for (i = 0; i < elems; i++) { 907 if (match(fromsec, check->fromsec) && 908 match(tosec, check->tosec)) 909 return check->mismatch; 910 check++; 911 } 912 return NO_MISMATCH; 913 } 914 915 /** 916 * Whitelist to allow certain references to pass with no warning. 917 * 918 * Pattern 0: 919 * Do not warn if funtion/data are marked with __init_refok/__initdata_refok. 920 * The pattern is identified by: 921 * fromsec = .text.init.refok* | .data.init.refok* 922 * 923 * Pattern 1: 924 * If a module parameter is declared __initdata and permissions=0 925 * then this is legal despite the warning generated. 926 * We cannot see value of permissions here, so just ignore 927 * this pattern. 928 * The pattern is identified by: 929 * tosec = .init.data 930 * fromsec = .data* 931 * atsym =__param* 932 * 933 * Pattern 2: 934 * Many drivers utilise a *driver container with references to 935 * add, remove, probe functions etc. 936 * These functions may often be marked __init and we do not want to 937 * warn here. 938 * the pattern is identified by: 939 * tosec = init or exit section 940 * fromsec = data section 941 * atsym = *driver, *_template, *_sht, *_ops, *_probe, 942 * *probe_one, *_console, *_timer 943 * 944 * Pattern 3: 945 * Whitelist all refereces from .text.head to .init.data 946 * Whitelist all refereces from .text.head to .init.text 947 * 948 * Pattern 4: 949 * Some symbols belong to init section but still it is ok to reference 950 * these from non-init sections as these symbols don't have any memory 951 * allocated for them and symbol address and value are same. So even 952 * if init section is freed, its ok to reference those symbols. 953 * For ex. symbols marking the init section boundaries. 954 * This pattern is identified by 955 * refsymname = __init_begin, _sinittext, _einittext 956 * 957 **/ 958 static int secref_whitelist(const char *fromsec, const char *fromsym, 959 const char *tosec, const char *tosym) 960 { 961 /* Check for pattern 0 */ 962 if (match(fromsec, initref_sections)) 963 return 0; 964 965 /* Check for pattern 1 */ 966 if (match(tosec, init_data_sections) && 967 match(fromsec, data_sections) && 968 (strncmp(fromsym, "__param", strlen("__param")) == 0)) 969 return 0; 970 971 /* Check for pattern 2 */ 972 if (match(tosec, init_exit_sections) && 973 match(fromsec, data_sections) && 974 match(fromsym, symbol_white_list)) 975 return 0; 976 977 /* Check for pattern 3 */ 978 if (match(fromsec, head_sections) && 979 match(tosec, init_sections)) 980 return 0; 981 982 /* Check for pattern 4 */ 983 if (match(tosym, linker_symbols)) 984 return 0; 985 986 return 1; 987 } 988 989 /** 990 * Find symbol based on relocation record info. 991 * In some cases the symbol supplied is a valid symbol so 992 * return refsym. If st_name != 0 we assume this is a valid symbol. 993 * In other cases the symbol needs to be looked up in the symbol table 994 * based on section and address. 995 * **/ 996 static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr, 997 Elf_Sym *relsym) 998 { 999 Elf_Sym *sym; 1000 Elf_Sym *near = NULL; 1001 Elf64_Sword distance = 20; 1002 Elf64_Sword d; 1003 1004 if (relsym->st_name != 0) 1005 return relsym; 1006 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { 1007 if (sym->st_shndx != relsym->st_shndx) 1008 continue; 1009 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION) 1010 continue; 1011 if (sym->st_value == addr) 1012 return sym; 1013 /* Find a symbol nearby - addr are maybe negative */ 1014 d = sym->st_value - addr; 1015 if (d < 0) 1016 d = addr - sym->st_value; 1017 if (d < distance) { 1018 distance = d; 1019 near = sym; 1020 } 1021 } 1022 /* We need a close match */ 1023 if (distance < 20) 1024 return near; 1025 else 1026 return NULL; 1027 } 1028 1029 static inline int is_arm_mapping_symbol(const char *str) 1030 { 1031 return str[0] == '$' && strchr("atd", str[1]) 1032 && (str[2] == '\0' || str[2] == '.'); 1033 } 1034 1035 /* 1036 * If there's no name there, ignore it; likewise, ignore it if it's 1037 * one of the magic symbols emitted used by current ARM tools. 1038 * 1039 * Otherwise if find_symbols_between() returns those symbols, they'll 1040 * fail the whitelist tests and cause lots of false alarms ... fixable 1041 * only by merging __exit and __init sections into __text, bloating 1042 * the kernel (which is especially evil on embedded platforms). 1043 */ 1044 static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym) 1045 { 1046 const char *name = elf->strtab + sym->st_name; 1047 1048 if (!name || !strlen(name)) 1049 return 0; 1050 return !is_arm_mapping_symbol(name); 1051 } 1052 1053 /* 1054 * Find symbols before or equal addr and after addr - in the section sec. 1055 * If we find two symbols with equal offset prefer one with a valid name. 1056 * The ELF format may have a better way to detect what type of symbol 1057 * it is, but this works for now. 1058 **/ 1059 static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr, 1060 const char *sec) 1061 { 1062 Elf_Sym *sym; 1063 Elf_Sym *near = NULL; 1064 Elf_Addr distance = ~0; 1065 1066 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { 1067 const char *symsec; 1068 1069 if (sym->st_shndx >= SHN_LORESERVE) 1070 continue; 1071 symsec = sec_name(elf, sym->st_shndx); 1072 if (strcmp(symsec, sec) != 0) 1073 continue; 1074 if (!is_valid_name(elf, sym)) 1075 continue; 1076 if (sym->st_value <= addr) { 1077 if ((addr - sym->st_value) < distance) { 1078 distance = addr - sym->st_value; 1079 near = sym; 1080 } else if ((addr - sym->st_value) == distance) { 1081 near = sym; 1082 } 1083 } 1084 } 1085 return near; 1086 } 1087 1088 /* 1089 * Convert a section name to the function/data attribute 1090 * .init.text => __init 1091 * .cpuinit.data => __cpudata 1092 * .memexitconst => __memconst 1093 * etc. 1094 */ 1095 static char *sec2annotation(const char *s) 1096 { 1097 if (match(s, init_exit_sections)) { 1098 char *p = malloc(20); 1099 char *r = p; 1100 1101 *p++ = '_'; 1102 *p++ = '_'; 1103 if (*s == '.') 1104 s++; 1105 while (*s && *s != '.') 1106 *p++ = *s++; 1107 *p = '\0'; 1108 if (*s == '.') 1109 s++; 1110 if (strstr(s, "rodata") != NULL) 1111 strcat(p, "const "); 1112 else if (strstr(s, "data") != NULL) 1113 strcat(p, "data "); 1114 else 1115 strcat(p, " "); 1116 return r; /* we leak her but we do not care */ 1117 } else { 1118 return ""; 1119 } 1120 } 1121 1122 static int is_function(Elf_Sym *sym) 1123 { 1124 if (sym) 1125 return ELF_ST_TYPE(sym->st_info) == STT_FUNC; 1126 else 1127 return -1; 1128 } 1129 1130 /* 1131 * Print a warning about a section mismatch. 1132 * Try to find symbols near it so user can find it. 1133 * Check whitelist before warning - it may be a false positive. 1134 */ 1135 static void report_sec_mismatch(const char *modname, enum mismatch mismatch, 1136 const char *fromsec, 1137 unsigned long long fromaddr, 1138 const char *fromsym, 1139 int from_is_func, 1140 const char *tosec, const char *tosym, 1141 int to_is_func) 1142 { 1143 const char *from, *from_p; 1144 const char *to, *to_p; 1145 1146 switch (from_is_func) { 1147 case 0: from = "variable"; from_p = ""; break; 1148 case 1: from = "function"; from_p = "()"; break; 1149 default: from = "(unknown reference)"; from_p = ""; break; 1150 } 1151 switch (to_is_func) { 1152 case 0: to = "variable"; to_p = ""; break; 1153 case 1: to = "function"; to_p = "()"; break; 1154 default: to = "(unknown reference)"; to_p = ""; break; 1155 } 1156 1157 sec_mismatch_count++; 1158 if (!sec_mismatch_verbose) 1159 return; 1160 1161 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s " 1162 "to the %s %s:%s%s\n", 1163 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec, 1164 tosym, to_p); 1165 1166 switch (mismatch) { 1167 case TEXT_TO_INIT: 1168 fprintf(stderr, 1169 "The function %s%s() references\n" 1170 "the %s %s%s%s.\n" 1171 "This is often because %s lacks a %s\n" 1172 "annotation or the annotation of %s is wrong.\n", 1173 sec2annotation(fromsec), fromsym, 1174 to, sec2annotation(tosec), tosym, to_p, 1175 fromsym, sec2annotation(tosec), tosym); 1176 break; 1177 case DATA_TO_INIT: { 1178 const char **s = symbol_white_list; 1179 fprintf(stderr, 1180 "The variable %s references\n" 1181 "the %s %s%s%s\n" 1182 "If the reference is valid then annotate the\n" 1183 "variable with __init* (see linux/init.h) " 1184 "or name the variable:\n", 1185 fromsym, to, sec2annotation(tosec), tosym, to_p); 1186 while (*s) 1187 fprintf(stderr, "%s, ", *s++); 1188 fprintf(stderr, "\n"); 1189 break; 1190 } 1191 case TEXT_TO_EXIT: 1192 fprintf(stderr, 1193 "The function %s() references a %s in an exit section.\n" 1194 "Often the %s %s%s has valid usage outside the exit section\n" 1195 "and the fix is to remove the %sannotation of %s.\n", 1196 fromsym, to, to, tosym, to_p, sec2annotation(tosec), tosym); 1197 break; 1198 case DATA_TO_EXIT: { 1199 const char **s = symbol_white_list; 1200 fprintf(stderr, 1201 "The variable %s references\n" 1202 "the %s %s%s%s\n" 1203 "If the reference is valid then annotate the\n" 1204 "variable with __exit* (see linux/init.h) or " 1205 "name the variable:\n", 1206 fromsym, to, sec2annotation(tosec), tosym, to_p); 1207 while (*s) 1208 fprintf(stderr, "%s, ", *s++); 1209 fprintf(stderr, "\n"); 1210 break; 1211 } 1212 case XXXINIT_TO_INIT: 1213 case XXXEXIT_TO_EXIT: 1214 fprintf(stderr, 1215 "The %s %s%s%s references\n" 1216 "a %s %s%s%s.\n" 1217 "If %s is only used by %s then\n" 1218 "annotate %s with a matching annotation.\n", 1219 from, sec2annotation(fromsec), fromsym, from_p, 1220 to, sec2annotation(tosec), tosym, to_p, 1221 tosym, fromsym, tosym); 1222 break; 1223 case INIT_TO_EXIT: 1224 fprintf(stderr, 1225 "The %s %s%s%s references\n" 1226 "a %s %s%s%s.\n" 1227 "This is often seen when error handling " 1228 "in the init function\n" 1229 "uses functionality in the exit path.\n" 1230 "The fix is often to remove the %sannotation of\n" 1231 "%s%s so it may be used outside an exit section.\n", 1232 from, sec2annotation(fromsec), fromsym, from_p, 1233 to, sec2annotation(tosec), tosym, to_p, 1234 sec2annotation(tosec), tosym, to_p); 1235 break; 1236 case EXIT_TO_INIT: 1237 fprintf(stderr, 1238 "The %s %s%s%s references\n" 1239 "a %s %s%s%s.\n" 1240 "This is often seen when error handling " 1241 "in the exit function\n" 1242 "uses functionality in the init path.\n" 1243 "The fix is often to remove the %sannotation of\n" 1244 "%s%s so it may be used outside an init section.\n", 1245 from, sec2annotation(fromsec), fromsym, from_p, 1246 to, sec2annotation(tosec), tosym, to_p, 1247 sec2annotation(tosec), tosym, to_p); 1248 break; 1249 case EXPORT_TO_INIT_EXIT: 1250 fprintf(stderr, 1251 "The symbol %s is exported and annotated %s\n" 1252 "Fix this by removing the %sannotation of %s " 1253 "or drop the export.\n", 1254 tosym, sec2annotation(tosec), sec2annotation(tosec), tosym); 1255 case NO_MISMATCH: 1256 /* To get warnings on missing members */ 1257 break; 1258 } 1259 fprintf(stderr, "\n"); 1260 } 1261 1262 static void check_section_mismatch(const char *modname, struct elf_info *elf, 1263 Elf_Rela *r, Elf_Sym *sym, const char *fromsec) 1264 { 1265 const char *tosec; 1266 enum mismatch mismatch; 1267 1268 tosec = sec_name(elf, sym->st_shndx); 1269 mismatch = section_mismatch(fromsec, tosec); 1270 if (mismatch != NO_MISMATCH) { 1271 Elf_Sym *to; 1272 Elf_Sym *from; 1273 const char *tosym; 1274 const char *fromsym; 1275 1276 from = find_elf_symbol2(elf, r->r_offset, fromsec); 1277 fromsym = sym_name(elf, from); 1278 to = find_elf_symbol(elf, r->r_addend, sym); 1279 tosym = sym_name(elf, to); 1280 1281 /* check whitelist - we may ignore it */ 1282 if (secref_whitelist(fromsec, fromsym, tosec, tosym)) { 1283 report_sec_mismatch(modname, mismatch, 1284 fromsec, r->r_offset, fromsym, 1285 is_function(from), tosec, tosym, 1286 is_function(to)); 1287 } 1288 } 1289 } 1290 1291 static unsigned int *reloc_location(struct elf_info *elf, 1292 Elf_Shdr *sechdr, Elf_Rela *r) 1293 { 1294 Elf_Shdr *sechdrs = elf->sechdrs; 1295 int section = sechdr->sh_info; 1296 1297 return (void *)elf->hdr + sechdrs[section].sh_offset + 1298 (r->r_offset - sechdrs[section].sh_addr); 1299 } 1300 1301 static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1302 { 1303 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1304 unsigned int *location = reloc_location(elf, sechdr, r); 1305 1306 switch (r_typ) { 1307 case R_386_32: 1308 r->r_addend = TO_NATIVE(*location); 1309 break; 1310 case R_386_PC32: 1311 r->r_addend = TO_NATIVE(*location) + 4; 1312 /* For CONFIG_RELOCATABLE=y */ 1313 if (elf->hdr->e_type == ET_EXEC) 1314 r->r_addend += r->r_offset; 1315 break; 1316 } 1317 return 0; 1318 } 1319 1320 static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1321 { 1322 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1323 1324 switch (r_typ) { 1325 case R_ARM_ABS32: 1326 /* From ARM ABI: (S + A) | T */ 1327 r->r_addend = (int)(long) 1328 (elf->symtab_start + ELF_R_SYM(r->r_info)); 1329 break; 1330 case R_ARM_PC24: 1331 /* From ARM ABI: ((S + A) | T) - P */ 1332 r->r_addend = (int)(long)(elf->hdr + 1333 sechdr->sh_offset + 1334 (r->r_offset - sechdr->sh_addr)); 1335 break; 1336 default: 1337 return 1; 1338 } 1339 return 0; 1340 } 1341 1342 static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1343 { 1344 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1345 unsigned int *location = reloc_location(elf, sechdr, r); 1346 unsigned int inst; 1347 1348 if (r_typ == R_MIPS_HI16) 1349 return 1; /* skip this */ 1350 inst = TO_NATIVE(*location); 1351 switch (r_typ) { 1352 case R_MIPS_LO16: 1353 r->r_addend = inst & 0xffff; 1354 break; 1355 case R_MIPS_26: 1356 r->r_addend = (inst & 0x03ffffff) << 2; 1357 break; 1358 case R_MIPS_32: 1359 r->r_addend = inst; 1360 break; 1361 } 1362 return 0; 1363 } 1364 1365 static void section_rela(const char *modname, struct elf_info *elf, 1366 Elf_Shdr *sechdr) 1367 { 1368 Elf_Sym *sym; 1369 Elf_Rela *rela; 1370 Elf_Rela r; 1371 unsigned int r_sym; 1372 const char *fromsec; 1373 1374 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset; 1375 Elf_Rela *stop = (void *)start + sechdr->sh_size; 1376 1377 fromsec = sech_name(elf, sechdr); 1378 fromsec += strlen(".rela"); 1379 /* if from section (name) is know good then skip it */ 1380 if (check_section(modname, fromsec)) 1381 return; 1382 1383 for (rela = start; rela < stop; rela++) { 1384 r.r_offset = TO_NATIVE(rela->r_offset); 1385 #if KERNEL_ELFCLASS == ELFCLASS64 1386 if (elf->hdr->e_machine == EM_MIPS) { 1387 unsigned int r_typ; 1388 r_sym = ELF64_MIPS_R_SYM(rela->r_info); 1389 r_sym = TO_NATIVE(r_sym); 1390 r_typ = ELF64_MIPS_R_TYPE(rela->r_info); 1391 r.r_info = ELF64_R_INFO(r_sym, r_typ); 1392 } else { 1393 r.r_info = TO_NATIVE(rela->r_info); 1394 r_sym = ELF_R_SYM(r.r_info); 1395 } 1396 #else 1397 r.r_info = TO_NATIVE(rela->r_info); 1398 r_sym = ELF_R_SYM(r.r_info); 1399 #endif 1400 r.r_addend = TO_NATIVE(rela->r_addend); 1401 sym = elf->symtab_start + r_sym; 1402 /* Skip special sections */ 1403 if (sym->st_shndx >= SHN_LORESERVE) 1404 continue; 1405 check_section_mismatch(modname, elf, &r, sym, fromsec); 1406 } 1407 } 1408 1409 static void section_rel(const char *modname, struct elf_info *elf, 1410 Elf_Shdr *sechdr) 1411 { 1412 Elf_Sym *sym; 1413 Elf_Rel *rel; 1414 Elf_Rela r; 1415 unsigned int r_sym; 1416 const char *fromsec; 1417 1418 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset; 1419 Elf_Rel *stop = (void *)start + sechdr->sh_size; 1420 1421 fromsec = sech_name(elf, sechdr); 1422 fromsec += strlen(".rel"); 1423 /* if from section (name) is know good then skip it */ 1424 if (check_section(modname, fromsec)) 1425 return; 1426 1427 for (rel = start; rel < stop; rel++) { 1428 r.r_offset = TO_NATIVE(rel->r_offset); 1429 #if KERNEL_ELFCLASS == ELFCLASS64 1430 if (elf->hdr->e_machine == EM_MIPS) { 1431 unsigned int r_typ; 1432 r_sym = ELF64_MIPS_R_SYM(rel->r_info); 1433 r_sym = TO_NATIVE(r_sym); 1434 r_typ = ELF64_MIPS_R_TYPE(rel->r_info); 1435 r.r_info = ELF64_R_INFO(r_sym, r_typ); 1436 } else { 1437 r.r_info = TO_NATIVE(rel->r_info); 1438 r_sym = ELF_R_SYM(r.r_info); 1439 } 1440 #else 1441 r.r_info = TO_NATIVE(rel->r_info); 1442 r_sym = ELF_R_SYM(r.r_info); 1443 #endif 1444 r.r_addend = 0; 1445 switch (elf->hdr->e_machine) { 1446 case EM_386: 1447 if (addend_386_rel(elf, sechdr, &r)) 1448 continue; 1449 break; 1450 case EM_ARM: 1451 if (addend_arm_rel(elf, sechdr, &r)) 1452 continue; 1453 break; 1454 case EM_MIPS: 1455 if (addend_mips_rel(elf, sechdr, &r)) 1456 continue; 1457 break; 1458 } 1459 sym = elf->symtab_start + r_sym; 1460 /* Skip special sections */ 1461 if (sym->st_shndx >= SHN_LORESERVE) 1462 continue; 1463 check_section_mismatch(modname, elf, &r, sym, fromsec); 1464 } 1465 } 1466 1467 /** 1468 * A module includes a number of sections that are discarded 1469 * either when loaded or when used as built-in. 1470 * For loaded modules all functions marked __init and all data 1471 * marked __initdata will be discarded when the module has been intialized. 1472 * Likewise for modules used built-in the sections marked __exit 1473 * are discarded because __exit marked function are supposed to be called 1474 * only when a module is unloaded which never happens for built-in modules. 1475 * The check_sec_ref() function traverses all relocation records 1476 * to find all references to a section that reference a section that will 1477 * be discarded and warns about it. 1478 **/ 1479 static void check_sec_ref(struct module *mod, const char *modname, 1480 struct elf_info *elf) 1481 { 1482 int i; 1483 Elf_Shdr *sechdrs = elf->sechdrs; 1484 1485 /* Walk through all sections */ 1486 for (i = 0; i < elf->hdr->e_shnum; i++) { 1487 /* We want to process only relocation sections and not .init */ 1488 if (sechdrs[i].sh_type == SHT_RELA) 1489 section_rela(modname, elf, &elf->sechdrs[i]); 1490 else if (sechdrs[i].sh_type == SHT_REL) 1491 section_rel(modname, elf, &elf->sechdrs[i]); 1492 } 1493 } 1494 1495 static void get_markers(struct elf_info *info, struct module *mod) 1496 { 1497 const Elf_Shdr *sh = &info->sechdrs[info->markers_strings_sec]; 1498 const char *strings = (const char *) info->hdr + sh->sh_offset; 1499 const Elf_Sym *sym, *first_sym, *last_sym; 1500 size_t n; 1501 1502 if (!info->markers_strings_sec) 1503 return; 1504 1505 /* 1506 * First count the strings. We look for all the symbols defined 1507 * in the __markers_strings section named __mstrtab_*. For 1508 * these local names, the compiler puts a random .NNN suffix on, 1509 * so the names don't correspond exactly. 1510 */ 1511 first_sym = last_sym = NULL; 1512 n = 0; 1513 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) 1514 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT && 1515 sym->st_shndx == info->markers_strings_sec && 1516 !strncmp(info->strtab + sym->st_name, 1517 "__mstrtab_", sizeof "__mstrtab_" - 1)) { 1518 if (first_sym == NULL) 1519 first_sym = sym; 1520 last_sym = sym; 1521 ++n; 1522 } 1523 1524 if (n == 0) 1525 return; 1526 1527 /* 1528 * Now collect each name and format into a line for the output. 1529 * Lines look like: 1530 * marker_name vmlinux marker %s format %d 1531 * The format string after the second \t can use whitespace. 1532 */ 1533 mod->markers = NOFAIL(malloc(sizeof mod->markers[0] * n)); 1534 mod->nmarkers = n; 1535 1536 n = 0; 1537 for (sym = first_sym; sym <= last_sym; sym++) 1538 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT && 1539 sym->st_shndx == info->markers_strings_sec && 1540 !strncmp(info->strtab + sym->st_name, 1541 "__mstrtab_", sizeof "__mstrtab_" - 1)) { 1542 const char *name = strings + sym->st_value; 1543 const char *fmt = strchr(name, '\0') + 1; 1544 char *line = NULL; 1545 asprintf(&line, "%s\t%s\t%s\n", name, mod->name, fmt); 1546 NOFAIL(line); 1547 mod->markers[n++] = line; 1548 } 1549 } 1550 1551 static void read_symbols(char *modname) 1552 { 1553 const char *symname; 1554 char *version; 1555 char *license; 1556 struct module *mod; 1557 struct elf_info info = { }; 1558 Elf_Sym *sym; 1559 1560 if (!parse_elf(&info, modname)) 1561 return; 1562 1563 mod = new_module(modname); 1564 1565 /* When there's no vmlinux, don't print warnings about 1566 * unresolved symbols (since there'll be too many ;) */ 1567 if (is_vmlinux(modname)) { 1568 have_vmlinux = 1; 1569 mod->skip = 1; 1570 } 1571 1572 license = get_modinfo(info.modinfo, info.modinfo_len, "license"); 1573 if (info.modinfo && !license && !is_vmlinux(modname)) 1574 warn("modpost: missing MODULE_LICENSE() in %s\n" 1575 "see include/linux/module.h for " 1576 "more information\n", modname); 1577 while (license) { 1578 if (license_is_gpl_compatible(license)) 1579 mod->gpl_compatible = 1; 1580 else { 1581 mod->gpl_compatible = 0; 1582 break; 1583 } 1584 license = get_next_modinfo(info.modinfo, info.modinfo_len, 1585 "license", license); 1586 } 1587 1588 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { 1589 symname = info.strtab + sym->st_name; 1590 1591 handle_modversions(mod, &info, sym, symname); 1592 handle_moddevtable(mod, &info, sym, symname); 1593 } 1594 if (!is_vmlinux(modname) || 1595 (is_vmlinux(modname) && vmlinux_section_warnings)) 1596 check_sec_ref(mod, modname, &info); 1597 1598 version = get_modinfo(info.modinfo, info.modinfo_len, "version"); 1599 if (version) 1600 maybe_frob_rcs_version(modname, version, info.modinfo, 1601 version - (char *)info.hdr); 1602 if (version || (all_versions && !is_vmlinux(modname))) 1603 get_src_version(modname, mod->srcversion, 1604 sizeof(mod->srcversion)-1); 1605 1606 get_markers(&info, mod); 1607 1608 parse_elf_finish(&info); 1609 1610 /* Our trick to get versioning for struct_module - it's 1611 * never passed as an argument to an exported function, so 1612 * the automatic versioning doesn't pick it up, but it's really 1613 * important anyhow */ 1614 if (modversions) 1615 mod->unres = alloc_symbol("struct_module", 0, mod->unres); 1616 } 1617 1618 #define SZ 500 1619 1620 /* We first write the generated file into memory using the 1621 * following helper, then compare to the file on disk and 1622 * only update the later if anything changed */ 1623 1624 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf, 1625 const char *fmt, ...) 1626 { 1627 char tmp[SZ]; 1628 int len; 1629 va_list ap; 1630 1631 va_start(ap, fmt); 1632 len = vsnprintf(tmp, SZ, fmt, ap); 1633 buf_write(buf, tmp, len); 1634 va_end(ap); 1635 } 1636 1637 void buf_write(struct buffer *buf, const char *s, int len) 1638 { 1639 if (buf->size - buf->pos < len) { 1640 buf->size += len + SZ; 1641 buf->p = realloc(buf->p, buf->size); 1642 } 1643 strncpy(buf->p + buf->pos, s, len); 1644 buf->pos += len; 1645 } 1646 1647 static void check_for_gpl_usage(enum export exp, const char *m, const char *s) 1648 { 1649 const char *e = is_vmlinux(m) ?"":".ko"; 1650 1651 switch (exp) { 1652 case export_gpl: 1653 fatal("modpost: GPL-incompatible module %s%s " 1654 "uses GPL-only symbol '%s'\n", m, e, s); 1655 break; 1656 case export_unused_gpl: 1657 fatal("modpost: GPL-incompatible module %s%s " 1658 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s); 1659 break; 1660 case export_gpl_future: 1661 warn("modpost: GPL-incompatible module %s%s " 1662 "uses future GPL-only symbol '%s'\n", m, e, s); 1663 break; 1664 case export_plain: 1665 case export_unused: 1666 case export_unknown: 1667 /* ignore */ 1668 break; 1669 } 1670 } 1671 1672 static void check_for_unused(enum export exp, const char *m, const char *s) 1673 { 1674 const char *e = is_vmlinux(m) ?"":".ko"; 1675 1676 switch (exp) { 1677 case export_unused: 1678 case export_unused_gpl: 1679 warn("modpost: module %s%s " 1680 "uses symbol '%s' marked UNUSED\n", m, e, s); 1681 break; 1682 default: 1683 /* ignore */ 1684 break; 1685 } 1686 } 1687 1688 static void check_exports(struct module *mod) 1689 { 1690 struct symbol *s, *exp; 1691 1692 for (s = mod->unres; s; s = s->next) { 1693 const char *basename; 1694 exp = find_symbol(s->name); 1695 if (!exp || exp->module == mod) 1696 continue; 1697 basename = strrchr(mod->name, '/'); 1698 if (basename) 1699 basename++; 1700 else 1701 basename = mod->name; 1702 if (!mod->gpl_compatible) 1703 check_for_gpl_usage(exp->export, basename, exp->name); 1704 check_for_unused(exp->export, basename, exp->name); 1705 } 1706 } 1707 1708 /** 1709 * Header for the generated file 1710 **/ 1711 static void add_header(struct buffer *b, struct module *mod) 1712 { 1713 buf_printf(b, "#include <linux/module.h>\n"); 1714 buf_printf(b, "#include <linux/vermagic.h>\n"); 1715 buf_printf(b, "#include <linux/compiler.h>\n"); 1716 buf_printf(b, "\n"); 1717 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n"); 1718 buf_printf(b, "\n"); 1719 buf_printf(b, "struct module __this_module\n"); 1720 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n"); 1721 buf_printf(b, " .name = KBUILD_MODNAME,\n"); 1722 if (mod->has_init) 1723 buf_printf(b, " .init = init_module,\n"); 1724 if (mod->has_cleanup) 1725 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n" 1726 " .exit = cleanup_module,\n" 1727 "#endif\n"); 1728 buf_printf(b, " .arch = MODULE_ARCH_INIT,\n"); 1729 buf_printf(b, "};\n"); 1730 } 1731 1732 void add_staging_flag(struct buffer *b, const char *name) 1733 { 1734 static const char *staging_dir = "drivers/staging"; 1735 1736 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0) 1737 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); 1738 } 1739 1740 /** 1741 * Record CRCs for unresolved symbols 1742 **/ 1743 static int add_versions(struct buffer *b, struct module *mod) 1744 { 1745 struct symbol *s, *exp; 1746 int err = 0; 1747 1748 for (s = mod->unres; s; s = s->next) { 1749 exp = find_symbol(s->name); 1750 if (!exp || exp->module == mod) { 1751 if (have_vmlinux && !s->weak) { 1752 if (warn_unresolved) { 1753 warn("\"%s\" [%s.ko] undefined!\n", 1754 s->name, mod->name); 1755 } else { 1756 merror("\"%s\" [%s.ko] undefined!\n", 1757 s->name, mod->name); 1758 err = 1; 1759 } 1760 } 1761 continue; 1762 } 1763 s->module = exp->module; 1764 s->crc_valid = exp->crc_valid; 1765 s->crc = exp->crc; 1766 } 1767 1768 if (!modversions) 1769 return err; 1770 1771 buf_printf(b, "\n"); 1772 buf_printf(b, "static const struct modversion_info ____versions[]\n"); 1773 buf_printf(b, "__used\n"); 1774 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n"); 1775 1776 for (s = mod->unres; s; s = s->next) { 1777 if (!s->module) 1778 continue; 1779 if (!s->crc_valid) { 1780 warn("\"%s\" [%s.ko] has no CRC!\n", 1781 s->name, mod->name); 1782 continue; 1783 } 1784 buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name); 1785 } 1786 1787 buf_printf(b, "};\n"); 1788 1789 return err; 1790 } 1791 1792 static void add_depends(struct buffer *b, struct module *mod, 1793 struct module *modules) 1794 { 1795 struct symbol *s; 1796 struct module *m; 1797 int first = 1; 1798 1799 for (m = modules; m; m = m->next) 1800 m->seen = is_vmlinux(m->name); 1801 1802 buf_printf(b, "\n"); 1803 buf_printf(b, "static const char __module_depends[]\n"); 1804 buf_printf(b, "__used\n"); 1805 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n"); 1806 buf_printf(b, "\"depends="); 1807 for (s = mod->unres; s; s = s->next) { 1808 const char *p; 1809 if (!s->module) 1810 continue; 1811 1812 if (s->module->seen) 1813 continue; 1814 1815 s->module->seen = 1; 1816 p = strrchr(s->module->name, '/'); 1817 if (p) 1818 p++; 1819 else 1820 p = s->module->name; 1821 buf_printf(b, "%s%s", first ? "" : ",", p); 1822 first = 0; 1823 } 1824 buf_printf(b, "\";\n"); 1825 } 1826 1827 static void add_srcversion(struct buffer *b, struct module *mod) 1828 { 1829 if (mod->srcversion[0]) { 1830 buf_printf(b, "\n"); 1831 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n", 1832 mod->srcversion); 1833 } 1834 } 1835 1836 static void write_if_changed(struct buffer *b, const char *fname) 1837 { 1838 char *tmp; 1839 FILE *file; 1840 struct stat st; 1841 1842 file = fopen(fname, "r"); 1843 if (!file) 1844 goto write; 1845 1846 if (fstat(fileno(file), &st) < 0) 1847 goto close_write; 1848 1849 if (st.st_size != b->pos) 1850 goto close_write; 1851 1852 tmp = NOFAIL(malloc(b->pos)); 1853 if (fread(tmp, 1, b->pos, file) != b->pos) 1854 goto free_write; 1855 1856 if (memcmp(tmp, b->p, b->pos) != 0) 1857 goto free_write; 1858 1859 free(tmp); 1860 fclose(file); 1861 return; 1862 1863 free_write: 1864 free(tmp); 1865 close_write: 1866 fclose(file); 1867 write: 1868 file = fopen(fname, "w"); 1869 if (!file) { 1870 perror(fname); 1871 exit(1); 1872 } 1873 if (fwrite(b->p, 1, b->pos, file) != b->pos) { 1874 perror(fname); 1875 exit(1); 1876 } 1877 fclose(file); 1878 } 1879 1880 /* parse Module.symvers file. line format: 1881 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something] 1882 **/ 1883 static void read_dump(const char *fname, unsigned int kernel) 1884 { 1885 unsigned long size, pos = 0; 1886 void *file = grab_file(fname, &size); 1887 char *line; 1888 1889 if (!file) 1890 /* No symbol versions, silently ignore */ 1891 return; 1892 1893 while ((line = get_next_line(&pos, file, size))) { 1894 char *symname, *modname, *d, *export, *end; 1895 unsigned int crc; 1896 struct module *mod; 1897 struct symbol *s; 1898 1899 if (!(symname = strchr(line, '\t'))) 1900 goto fail; 1901 *symname++ = '\0'; 1902 if (!(modname = strchr(symname, '\t'))) 1903 goto fail; 1904 *modname++ = '\0'; 1905 if ((export = strchr(modname, '\t')) != NULL) 1906 *export++ = '\0'; 1907 if (export && ((end = strchr(export, '\t')) != NULL)) 1908 *end = '\0'; 1909 crc = strtoul(line, &d, 16); 1910 if (*symname == '\0' || *modname == '\0' || *d != '\0') 1911 goto fail; 1912 mod = find_module(modname); 1913 if (!mod) { 1914 if (is_vmlinux(modname)) 1915 have_vmlinux = 1; 1916 mod = new_module(NOFAIL(strdup(modname))); 1917 mod->skip = 1; 1918 } 1919 s = sym_add_exported(symname, mod, export_no(export)); 1920 s->kernel = kernel; 1921 s->preloaded = 1; 1922 sym_update_crc(symname, mod, crc, export_no(export)); 1923 } 1924 return; 1925 fail: 1926 fatal("parse error in symbol dump file\n"); 1927 } 1928 1929 /* For normal builds always dump all symbols. 1930 * For external modules only dump symbols 1931 * that are not read from kernel Module.symvers. 1932 **/ 1933 static int dump_sym(struct symbol *sym) 1934 { 1935 if (!external_module) 1936 return 1; 1937 if (sym->vmlinux || sym->kernel) 1938 return 0; 1939 return 1; 1940 } 1941 1942 static void write_dump(const char *fname) 1943 { 1944 struct buffer buf = { }; 1945 struct symbol *symbol; 1946 int n; 1947 1948 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) { 1949 symbol = symbolhash[n]; 1950 while (symbol) { 1951 if (dump_sym(symbol)) 1952 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n", 1953 symbol->crc, symbol->name, 1954 symbol->module->name, 1955 export_str(symbol->export)); 1956 symbol = symbol->next; 1957 } 1958 } 1959 write_if_changed(&buf, fname); 1960 } 1961 1962 static void add_marker(struct module *mod, const char *name, const char *fmt) 1963 { 1964 char *line = NULL; 1965 asprintf(&line, "%s\t%s\t%s\n", name, mod->name, fmt); 1966 NOFAIL(line); 1967 1968 mod->markers = NOFAIL(realloc(mod->markers, ((mod->nmarkers + 1) * 1969 sizeof mod->markers[0]))); 1970 mod->markers[mod->nmarkers++] = line; 1971 } 1972 1973 static void read_markers(const char *fname) 1974 { 1975 unsigned long size, pos = 0; 1976 void *file = grab_file(fname, &size); 1977 char *line; 1978 1979 if (!file) /* No old markers, silently ignore */ 1980 return; 1981 1982 while ((line = get_next_line(&pos, file, size))) { 1983 char *marker, *modname, *fmt; 1984 struct module *mod; 1985 1986 marker = line; 1987 modname = strchr(marker, '\t'); 1988 if (!modname) 1989 goto fail; 1990 *modname++ = '\0'; 1991 fmt = strchr(modname, '\t'); 1992 if (!fmt) 1993 goto fail; 1994 *fmt++ = '\0'; 1995 if (*marker == '\0' || *modname == '\0') 1996 goto fail; 1997 1998 mod = find_module(modname); 1999 if (!mod) { 2000 mod = new_module(NOFAIL(strdup(modname))); 2001 mod->skip = 1; 2002 } 2003 if (is_vmlinux(modname)) { 2004 have_vmlinux = 1; 2005 mod->skip = 0; 2006 } 2007 2008 if (!mod->skip) 2009 add_marker(mod, marker, fmt); 2010 } 2011 return; 2012 fail: 2013 fatal("parse error in markers list file\n"); 2014 } 2015 2016 static int compare_strings(const void *a, const void *b) 2017 { 2018 return strcmp(*(const char **) a, *(const char **) b); 2019 } 2020 2021 static void write_markers(const char *fname) 2022 { 2023 struct buffer buf = { }; 2024 struct module *mod; 2025 size_t i; 2026 2027 for (mod = modules; mod; mod = mod->next) 2028 if ((!external_module || !mod->skip) && mod->markers != NULL) { 2029 /* 2030 * Sort the strings so we can skip duplicates when 2031 * we write them out. 2032 */ 2033 qsort(mod->markers, mod->nmarkers, 2034 sizeof mod->markers[0], &compare_strings); 2035 for (i = 0; i < mod->nmarkers; ++i) { 2036 char *line = mod->markers[i]; 2037 buf_write(&buf, line, strlen(line)); 2038 while (i + 1 < mod->nmarkers && 2039 !strcmp(mod->markers[i], 2040 mod->markers[i + 1])) 2041 free(mod->markers[i++]); 2042 free(mod->markers[i]); 2043 } 2044 free(mod->markers); 2045 mod->markers = NULL; 2046 } 2047 2048 write_if_changed(&buf, fname); 2049 } 2050 2051 struct ext_sym_list { 2052 struct ext_sym_list *next; 2053 const char *file; 2054 }; 2055 2056 int main(int argc, char **argv) 2057 { 2058 struct module *mod; 2059 struct buffer buf = { }; 2060 char *kernel_read = NULL, *module_read = NULL; 2061 char *dump_write = NULL; 2062 char *markers_read = NULL; 2063 char *markers_write = NULL; 2064 int opt; 2065 int err; 2066 struct ext_sym_list *extsym_iter; 2067 struct ext_sym_list *extsym_start = NULL; 2068 2069 while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) { 2070 switch (opt) { 2071 case 'i': 2072 kernel_read = optarg; 2073 break; 2074 case 'I': 2075 module_read = optarg; 2076 external_module = 1; 2077 break; 2078 case 'c': 2079 cross_build = 1; 2080 break; 2081 case 'e': 2082 external_module = 1; 2083 extsym_iter = 2084 NOFAIL(malloc(sizeof(*extsym_iter))); 2085 extsym_iter->next = extsym_start; 2086 extsym_iter->file = optarg; 2087 extsym_start = extsym_iter; 2088 break; 2089 case 'm': 2090 modversions = 1; 2091 break; 2092 case 'o': 2093 dump_write = optarg; 2094 break; 2095 case 'a': 2096 all_versions = 1; 2097 break; 2098 case 's': 2099 vmlinux_section_warnings = 0; 2100 break; 2101 case 'S': 2102 sec_mismatch_verbose = 0; 2103 break; 2104 case 'w': 2105 warn_unresolved = 1; 2106 break; 2107 case 'M': 2108 markers_write = optarg; 2109 break; 2110 case 'K': 2111 markers_read = optarg; 2112 break; 2113 default: 2114 exit(1); 2115 } 2116 } 2117 2118 if (kernel_read) 2119 read_dump(kernel_read, 1); 2120 if (module_read) 2121 read_dump(module_read, 0); 2122 while (extsym_start) { 2123 read_dump(extsym_start->file, 0); 2124 extsym_iter = extsym_start->next; 2125 free(extsym_start); 2126 extsym_start = extsym_iter; 2127 } 2128 2129 while (optind < argc) 2130 read_symbols(argv[optind++]); 2131 2132 for (mod = modules; mod; mod = mod->next) { 2133 if (mod->skip) 2134 continue; 2135 check_exports(mod); 2136 } 2137 2138 err = 0; 2139 2140 for (mod = modules; mod; mod = mod->next) { 2141 char fname[strlen(mod->name) + 10]; 2142 2143 if (mod->skip) 2144 continue; 2145 2146 buf.pos = 0; 2147 2148 add_header(&buf, mod); 2149 add_staging_flag(&buf, mod->name); 2150 err |= add_versions(&buf, mod); 2151 add_depends(&buf, mod, modules); 2152 add_moddevtable(&buf, mod); 2153 add_srcversion(&buf, mod); 2154 2155 sprintf(fname, "%s.mod.c", mod->name); 2156 write_if_changed(&buf, fname); 2157 } 2158 2159 if (dump_write) 2160 write_dump(dump_write); 2161 if (sec_mismatch_count && !sec_mismatch_verbose) 2162 warn("modpost: Found %d section mismatch(es).\n" 2163 "To see full details build your kernel with:\n" 2164 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n", 2165 sec_mismatch_count); 2166 2167 if (markers_read) 2168 read_markers(markers_read); 2169 2170 if (markers_write) 2171 write_markers(markers_write); 2172 2173 return err; 2174 } 2175