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/generated/autoconf.h" 19 #include "../../include/linux/license.h" 20 21 /* Some toolchains use a `_' prefix for all user symbols. */ 22 #ifdef CONFIG_SYMBOL_PREFIX 23 #define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX 24 #else 25 #define MODULE_SYMBOL_PREFIX "" 26 #endif 27 28 29 /* Are we using CONFIG_MODVERSIONS? */ 30 int modversions = 0; 31 /* Warn about undefined symbols? (do so if we have vmlinux) */ 32 int have_vmlinux = 0; 33 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ 34 static int all_versions = 0; 35 /* If we are modposting external module set to 1 */ 36 static int external_module = 0; 37 /* Warn about section mismatch in vmlinux if set to 1 */ 38 static int vmlinux_section_warnings = 1; 39 /* Only warn about unresolved symbols */ 40 static int warn_unresolved = 0; 41 /* How a symbol is exported */ 42 static int sec_mismatch_count = 0; 43 static int sec_mismatch_verbose = 1; 44 45 enum export { 46 export_plain, export_unused, export_gpl, 47 export_unused_gpl, export_gpl_future, export_unknown 48 }; 49 50 #define PRINTF __attribute__ ((format (printf, 1, 2))) 51 52 PRINTF void fatal(const char *fmt, ...) 53 { 54 va_list arglist; 55 56 fprintf(stderr, "FATAL: "); 57 58 va_start(arglist, fmt); 59 vfprintf(stderr, fmt, arglist); 60 va_end(arglist); 61 62 exit(1); 63 } 64 65 PRINTF void warn(const char *fmt, ...) 66 { 67 va_list arglist; 68 69 fprintf(stderr, "WARNING: "); 70 71 va_start(arglist, fmt); 72 vfprintf(stderr, fmt, arglist); 73 va_end(arglist); 74 } 75 76 PRINTF void merror(const char *fmt, ...) 77 { 78 va_list arglist; 79 80 fprintf(stderr, "ERROR: "); 81 82 va_start(arglist, fmt); 83 vfprintf(stderr, fmt, arglist); 84 va_end(arglist); 85 } 86 87 static int is_vmlinux(const char *modname) 88 { 89 const char *myname; 90 91 myname = strrchr(modname, '/'); 92 if (myname) 93 myname++; 94 else 95 myname = modname; 96 97 return (strcmp(myname, "vmlinux") == 0) || 98 (strcmp(myname, "vmlinux.o") == 0); 99 } 100 101 void *do_nofail(void *ptr, const char *expr) 102 { 103 if (!ptr) 104 fatal("modpost: Memory allocation failure: %s.\n", expr); 105 106 return ptr; 107 } 108 109 /* A list of all modules we processed */ 110 static struct module *modules; 111 112 static struct module *find_module(char *modname) 113 { 114 struct module *mod; 115 116 for (mod = modules; mod; mod = mod->next) 117 if (strcmp(mod->name, modname) == 0) 118 break; 119 return mod; 120 } 121 122 static struct module *new_module(char *modname) 123 { 124 struct module *mod; 125 char *p, *s; 126 127 mod = NOFAIL(malloc(sizeof(*mod))); 128 memset(mod, 0, sizeof(*mod)); 129 p = NOFAIL(strdup(modname)); 130 131 /* strip trailing .o */ 132 s = strrchr(p, '.'); 133 if (s != NULL) 134 if (strcmp(s, ".o") == 0) 135 *s = '\0'; 136 137 /* add to list */ 138 mod->name = p; 139 mod->gpl_compatible = -1; 140 mod->next = modules; 141 modules = mod; 142 143 return mod; 144 } 145 146 /* A hash of all exported symbols, 147 * struct symbol is also used for lists of unresolved symbols */ 148 149 #define SYMBOL_HASH_SIZE 1024 150 151 struct symbol { 152 struct symbol *next; 153 struct module *module; 154 unsigned int crc; 155 int crc_valid; 156 unsigned int weak:1; 157 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */ 158 unsigned int kernel:1; /* 1 if symbol is from kernel 159 * (only for external modules) **/ 160 unsigned int preloaded:1; /* 1 if symbol from Module.symvers */ 161 enum export export; /* Type of export */ 162 char name[0]; 163 }; 164 165 static struct symbol *symbolhash[SYMBOL_HASH_SIZE]; 166 167 /* This is based on the hash agorithm from gdbm, via tdb */ 168 static inline unsigned int tdb_hash(const char *name) 169 { 170 unsigned value; /* Used to compute the hash value. */ 171 unsigned i; /* Used to cycle through random values. */ 172 173 /* Set the initial value from the key size. */ 174 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++) 175 value = (value + (((unsigned char *)name)[i] << (i*5 % 24))); 176 177 return (1103515243 * value + 12345); 178 } 179 180 /** 181 * Allocate a new symbols for use in the hash of exported symbols or 182 * the list of unresolved symbols per module 183 **/ 184 static struct symbol *alloc_symbol(const char *name, unsigned int weak, 185 struct symbol *next) 186 { 187 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1)); 188 189 memset(s, 0, sizeof(*s)); 190 strcpy(s->name, name); 191 s->weak = weak; 192 s->next = next; 193 return s; 194 } 195 196 /* For the hash of exported symbols */ 197 static struct symbol *new_symbol(const char *name, struct module *module, 198 enum export export) 199 { 200 unsigned int hash; 201 struct symbol *new; 202 203 hash = tdb_hash(name) % SYMBOL_HASH_SIZE; 204 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]); 205 new->module = module; 206 new->export = export; 207 return new; 208 } 209 210 static struct symbol *find_symbol(const char *name) 211 { 212 struct symbol *s; 213 214 /* For our purposes, .foo matches foo. PPC64 needs this. */ 215 if (name[0] == '.') 216 name++; 217 218 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) { 219 if (strcmp(s->name, name) == 0) 220 return s; 221 } 222 return NULL; 223 } 224 225 static struct { 226 const char *str; 227 enum export export; 228 } export_list[] = { 229 { .str = "EXPORT_SYMBOL", .export = export_plain }, 230 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused }, 231 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl }, 232 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl }, 233 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future }, 234 { .str = "(unknown)", .export = export_unknown }, 235 }; 236 237 238 static const char *export_str(enum export ex) 239 { 240 return export_list[ex].str; 241 } 242 243 static enum export export_no(const char *s) 244 { 245 int i; 246 247 if (!s) 248 return export_unknown; 249 for (i = 0; export_list[i].export != export_unknown; i++) { 250 if (strcmp(export_list[i].str, s) == 0) 251 return export_list[i].export; 252 } 253 return export_unknown; 254 } 255 256 static enum export export_from_sec(struct elf_info *elf, unsigned int sec) 257 { 258 if (sec == elf->export_sec) 259 return export_plain; 260 else if (sec == elf->export_unused_sec) 261 return export_unused; 262 else if (sec == elf->export_gpl_sec) 263 return export_gpl; 264 else if (sec == elf->export_unused_gpl_sec) 265 return export_unused_gpl; 266 else if (sec == elf->export_gpl_future_sec) 267 return export_gpl_future; 268 else 269 return export_unknown; 270 } 271 272 /** 273 * Add an exported symbol - it may have already been added without a 274 * CRC, in this case just update the CRC 275 **/ 276 static struct symbol *sym_add_exported(const char *name, struct module *mod, 277 enum export export) 278 { 279 struct symbol *s = find_symbol(name); 280 281 if (!s) { 282 s = new_symbol(name, mod, export); 283 } else { 284 if (!s->preloaded) { 285 warn("%s: '%s' exported twice. Previous export " 286 "was in %s%s\n", mod->name, name, 287 s->module->name, 288 is_vmlinux(s->module->name) ?"":".ko"); 289 } else { 290 /* In case Modules.symvers was out of date */ 291 s->module = mod; 292 } 293 } 294 s->preloaded = 0; 295 s->vmlinux = is_vmlinux(mod->name); 296 s->kernel = 0; 297 s->export = export; 298 return s; 299 } 300 301 static void sym_update_crc(const char *name, struct module *mod, 302 unsigned int crc, enum export export) 303 { 304 struct symbol *s = find_symbol(name); 305 306 if (!s) 307 s = new_symbol(name, mod, export); 308 s->crc = crc; 309 s->crc_valid = 1; 310 } 311 312 void *grab_file(const char *filename, unsigned long *size) 313 { 314 struct stat st; 315 void *map; 316 int fd; 317 318 fd = open(filename, O_RDONLY); 319 if (fd < 0 || fstat(fd, &st) != 0) 320 return NULL; 321 322 *size = st.st_size; 323 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); 324 close(fd); 325 326 if (map == MAP_FAILED) 327 return NULL; 328 return map; 329 } 330 331 /** 332 * Return a copy of the next line in a mmap'ed file. 333 * spaces in the beginning of the line is trimmed away. 334 * Return a pointer to a static buffer. 335 **/ 336 char *get_next_line(unsigned long *pos, void *file, unsigned long size) 337 { 338 static char line[4096]; 339 int skip = 1; 340 size_t len = 0; 341 signed char *p = (signed char *)file + *pos; 342 char *s = line; 343 344 for (; *pos < size ; (*pos)++) { 345 if (skip && isspace(*p)) { 346 p++; 347 continue; 348 } 349 skip = 0; 350 if (*p != '\n' && (*pos < size)) { 351 len++; 352 *s++ = *p++; 353 if (len > 4095) 354 break; /* Too long, stop */ 355 } else { 356 /* End of string */ 357 *s = '\0'; 358 return line; 359 } 360 } 361 /* End of buffer */ 362 return NULL; 363 } 364 365 void release_file(void *file, unsigned long size) 366 { 367 munmap(file, size); 368 } 369 370 static int parse_elf(struct elf_info *info, const char *filename) 371 { 372 unsigned int i; 373 Elf_Ehdr *hdr; 374 Elf_Shdr *sechdrs; 375 Elf_Sym *sym; 376 const char *secstrings; 377 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U; 378 379 hdr = grab_file(filename, &info->size); 380 if (!hdr) { 381 perror(filename); 382 exit(1); 383 } 384 info->hdr = hdr; 385 if (info->size < sizeof(*hdr)) { 386 /* file too small, assume this is an empty .o file */ 387 return 0; 388 } 389 /* Is this a valid ELF file? */ 390 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) || 391 (hdr->e_ident[EI_MAG1] != ELFMAG1) || 392 (hdr->e_ident[EI_MAG2] != ELFMAG2) || 393 (hdr->e_ident[EI_MAG3] != ELFMAG3)) { 394 /* Not an ELF file - silently ignore it */ 395 return 0; 396 } 397 /* Fix endianness in ELF header */ 398 hdr->e_type = TO_NATIVE(hdr->e_type); 399 hdr->e_machine = TO_NATIVE(hdr->e_machine); 400 hdr->e_version = TO_NATIVE(hdr->e_version); 401 hdr->e_entry = TO_NATIVE(hdr->e_entry); 402 hdr->e_phoff = TO_NATIVE(hdr->e_phoff); 403 hdr->e_shoff = TO_NATIVE(hdr->e_shoff); 404 hdr->e_flags = TO_NATIVE(hdr->e_flags); 405 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize); 406 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize); 407 hdr->e_phnum = TO_NATIVE(hdr->e_phnum); 408 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize); 409 hdr->e_shnum = TO_NATIVE(hdr->e_shnum); 410 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx); 411 sechdrs = (void *)hdr + hdr->e_shoff; 412 info->sechdrs = sechdrs; 413 414 /* Check if file offset is correct */ 415 if (hdr->e_shoff > info->size) { 416 fatal("section header offset=%lu in file '%s' is bigger than " 417 "filesize=%lu\n", (unsigned long)hdr->e_shoff, 418 filename, info->size); 419 return 0; 420 } 421 422 if (hdr->e_shnum == 0) { 423 /* 424 * There are more than 64k sections, 425 * read count from .sh_size. 426 * note: it doesn't need shndx2secindex() 427 */ 428 info->num_sections = TO_NATIVE(sechdrs[0].sh_size); 429 } 430 else { 431 info->num_sections = hdr->e_shnum; 432 } 433 if (hdr->e_shstrndx == SHN_XINDEX) { 434 info->secindex_strings = 435 shndx2secindex(TO_NATIVE(sechdrs[0].sh_link)); 436 } 437 else { 438 info->secindex_strings = hdr->e_shstrndx; 439 } 440 441 /* Fix endianness in section headers */ 442 for (i = 0; i < info->num_sections; i++) { 443 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name); 444 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); 445 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags); 446 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr); 447 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset); 448 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size); 449 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link); 450 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info); 451 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign); 452 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize); 453 } 454 /* Find symbol table. */ 455 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset; 456 for (i = 1; i < info->num_sections; i++) { 457 const char *secname; 458 int nobits = sechdrs[i].sh_type == SHT_NOBITS; 459 460 if (!nobits && sechdrs[i].sh_offset > info->size) { 461 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > " 462 "sizeof(*hrd)=%zu\n", filename, 463 (unsigned long)sechdrs[i].sh_offset, 464 sizeof(*hdr)); 465 return 0; 466 } 467 secname = secstrings + sechdrs[i].sh_name; 468 if (strcmp(secname, ".modinfo") == 0) { 469 if (nobits) 470 fatal("%s has NOBITS .modinfo\n", filename); 471 info->modinfo = (void *)hdr + sechdrs[i].sh_offset; 472 info->modinfo_len = sechdrs[i].sh_size; 473 } else if (strcmp(secname, "__ksymtab") == 0) 474 info->export_sec = i; 475 else if (strcmp(secname, "__ksymtab_unused") == 0) 476 info->export_unused_sec = i; 477 else if (strcmp(secname, "__ksymtab_gpl") == 0) 478 info->export_gpl_sec = i; 479 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0) 480 info->export_unused_gpl_sec = i; 481 else if (strcmp(secname, "__ksymtab_gpl_future") == 0) 482 info->export_gpl_future_sec = i; 483 484 if (sechdrs[i].sh_type == SHT_SYMTAB) { 485 unsigned int sh_link_idx; 486 symtab_idx = i; 487 info->symtab_start = (void *)hdr + 488 sechdrs[i].sh_offset; 489 info->symtab_stop = (void *)hdr + 490 sechdrs[i].sh_offset + sechdrs[i].sh_size; 491 sh_link_idx = shndx2secindex(sechdrs[i].sh_link); 492 info->strtab = (void *)hdr + 493 sechdrs[sh_link_idx].sh_offset; 494 } 495 496 /* 32bit section no. table? ("more than 64k sections") */ 497 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) { 498 symtab_shndx_idx = i; 499 info->symtab_shndx_start = (void *)hdr + 500 sechdrs[i].sh_offset; 501 info->symtab_shndx_stop = (void *)hdr + 502 sechdrs[i].sh_offset + sechdrs[i].sh_size; 503 } 504 } 505 if (!info->symtab_start) 506 fatal("%s has no symtab?\n", filename); 507 508 /* Fix endianness in symbols */ 509 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) { 510 sym->st_shndx = TO_NATIVE(sym->st_shndx); 511 sym->st_name = TO_NATIVE(sym->st_name); 512 sym->st_value = TO_NATIVE(sym->st_value); 513 sym->st_size = TO_NATIVE(sym->st_size); 514 } 515 516 if (symtab_shndx_idx != ~0U) { 517 Elf32_Word *p; 518 if (symtab_idx != 519 shndx2secindex(sechdrs[symtab_shndx_idx].sh_link)) 520 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n", 521 filename, 522 shndx2secindex(sechdrs[symtab_shndx_idx].sh_link), 523 symtab_idx); 524 /* Fix endianness */ 525 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop; 526 p++) 527 *p = TO_NATIVE(*p); 528 } 529 530 return 1; 531 } 532 533 static void parse_elf_finish(struct elf_info *info) 534 { 535 release_file(info->hdr, info->size); 536 } 537 538 static int ignore_undef_symbol(struct elf_info *info, const char *symname) 539 { 540 /* ignore __this_module, it will be resolved shortly */ 541 if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0) 542 return 1; 543 /* ignore global offset table */ 544 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0) 545 return 1; 546 if (info->hdr->e_machine == EM_PPC) 547 /* Special register function linked on all modules during final link of .ko */ 548 if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 || 549 strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 || 550 strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 || 551 strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0) 552 return 1; 553 if (info->hdr->e_machine == EM_PPC64) 554 /* Special register function linked on all modules during final link of .ko */ 555 if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 || 556 strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0) 557 return 1; 558 /* Do not ignore this symbol */ 559 return 0; 560 } 561 562 #define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_" 563 #define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_" 564 565 static void handle_modversions(struct module *mod, struct elf_info *info, 566 Elf_Sym *sym, const char *symname) 567 { 568 unsigned int crc; 569 enum export export = export_from_sec(info, get_secindex(info, sym)); 570 571 switch (sym->st_shndx) { 572 case SHN_COMMON: 573 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name); 574 break; 575 case SHN_ABS: 576 /* CRC'd symbol */ 577 if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) { 578 crc = (unsigned int) sym->st_value; 579 sym_update_crc(symname + strlen(CRC_PFX), mod, crc, 580 export); 581 } 582 break; 583 case SHN_UNDEF: 584 /* undefined symbol */ 585 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 586 ELF_ST_BIND(sym->st_info) != STB_WEAK) 587 break; 588 if (ignore_undef_symbol(info, symname)) 589 break; 590 /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */ 591 #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER) 592 /* add compatibility with older glibc */ 593 #ifndef STT_SPARC_REGISTER 594 #define STT_SPARC_REGISTER STT_REGISTER 595 #endif 596 if (info->hdr->e_machine == EM_SPARC || 597 info->hdr->e_machine == EM_SPARCV9) { 598 /* Ignore register directives. */ 599 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER) 600 break; 601 if (symname[0] == '.') { 602 char *munged = strdup(symname); 603 munged[0] = '_'; 604 munged[1] = toupper(munged[1]); 605 symname = munged; 606 } 607 } 608 #endif 609 610 if (memcmp(symname, MODULE_SYMBOL_PREFIX, 611 strlen(MODULE_SYMBOL_PREFIX)) == 0) { 612 mod->unres = 613 alloc_symbol(symname + 614 strlen(MODULE_SYMBOL_PREFIX), 615 ELF_ST_BIND(sym->st_info) == STB_WEAK, 616 mod->unres); 617 } 618 break; 619 default: 620 /* All exported symbols */ 621 if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) { 622 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod, 623 export); 624 } 625 if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0) 626 mod->has_init = 1; 627 if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0) 628 mod->has_cleanup = 1; 629 break; 630 } 631 } 632 633 /** 634 * Parse tag=value strings from .modinfo section 635 **/ 636 static char *next_string(char *string, unsigned long *secsize) 637 { 638 /* Skip non-zero chars */ 639 while (string[0]) { 640 string++; 641 if ((*secsize)-- <= 1) 642 return NULL; 643 } 644 645 /* Skip any zero padding. */ 646 while (!string[0]) { 647 string++; 648 if ((*secsize)-- <= 1) 649 return NULL; 650 } 651 return string; 652 } 653 654 static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len, 655 const char *tag, char *info) 656 { 657 char *p; 658 unsigned int taglen = strlen(tag); 659 unsigned long size = modinfo_len; 660 661 if (info) { 662 size -= info - (char *)modinfo; 663 modinfo = next_string(info, &size); 664 } 665 666 for (p = modinfo; p; p = next_string(p, &size)) { 667 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') 668 return p + taglen + 1; 669 } 670 return NULL; 671 } 672 673 static char *get_modinfo(void *modinfo, unsigned long modinfo_len, 674 const char *tag) 675 676 { 677 return get_next_modinfo(modinfo, modinfo_len, tag, NULL); 678 } 679 680 /** 681 * Test if string s ends in string sub 682 * return 0 if match 683 **/ 684 static int strrcmp(const char *s, const char *sub) 685 { 686 int slen, sublen; 687 688 if (!s || !sub) 689 return 1; 690 691 slen = strlen(s); 692 sublen = strlen(sub); 693 694 if ((slen == 0) || (sublen == 0)) 695 return 1; 696 697 if (sublen > slen) 698 return 1; 699 700 return memcmp(s + slen - sublen, sub, sublen); 701 } 702 703 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) 704 { 705 if (sym) 706 return elf->strtab + sym->st_name; 707 else 708 return "(unknown)"; 709 } 710 711 static const char *sec_name(struct elf_info *elf, int secindex) 712 { 713 Elf_Shdr *sechdrs = elf->sechdrs; 714 return (void *)elf->hdr + 715 elf->sechdrs[elf->secindex_strings].sh_offset + 716 sechdrs[secindex].sh_name; 717 } 718 719 static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr) 720 { 721 return (void *)elf->hdr + 722 elf->sechdrs[elf->secindex_strings].sh_offset + 723 sechdr->sh_name; 724 } 725 726 /* if sym is empty or point to a string 727 * like ".[0-9]+" then return 1. 728 * This is the optional prefix added by ld to some sections 729 */ 730 static int number_prefix(const char *sym) 731 { 732 if (*sym++ == '\0') 733 return 1; 734 if (*sym != '.') 735 return 0; 736 do { 737 char c = *sym++; 738 if (c < '0' || c > '9') 739 return 0; 740 } while (*sym); 741 return 1; 742 } 743 744 /* The pattern is an array of simple patterns. 745 * "foo" will match an exact string equal to "foo" 746 * "*foo" will match a string that ends with "foo" 747 * "foo*" will match a string that begins with "foo" 748 * "foo$" will match a string equal to "foo" or "foo.1" 749 * where the '1' can be any number including several digits. 750 * The $ syntax is for sections where ld append a dot number 751 * to make section name unique. 752 */ 753 static int match(const char *sym, const char * const pat[]) 754 { 755 const char *p; 756 while (*pat) { 757 p = *pat++; 758 const char *endp = p + strlen(p) - 1; 759 760 /* "*foo" */ 761 if (*p == '*') { 762 if (strrcmp(sym, p + 1) == 0) 763 return 1; 764 } 765 /* "foo*" */ 766 else if (*endp == '*') { 767 if (strncmp(sym, p, strlen(p) - 1) == 0) 768 return 1; 769 } 770 /* "foo$" */ 771 else if (*endp == '$') { 772 if (strncmp(sym, p, strlen(p) - 1) == 0) { 773 if (number_prefix(sym + strlen(p) - 1)) 774 return 1; 775 } 776 } 777 /* no wildcards */ 778 else { 779 if (strcmp(p, sym) == 0) 780 return 1; 781 } 782 } 783 /* no match */ 784 return 0; 785 } 786 787 /* sections that we do not want to do full section mismatch check on */ 788 static const char *section_white_list[] = 789 { 790 ".comment*", 791 ".debug*", 792 ".mdebug*", /* alpha, score, mips etc. */ 793 ".pdr", /* alpha, score, mips etc. */ 794 ".stab*", 795 ".note*", 796 ".got*", 797 ".toc*", 798 NULL 799 }; 800 801 /* 802 * This is used to find sections missing the SHF_ALLOC flag. 803 * The cause of this is often a section specified in assembler 804 * without "ax" / "aw". 805 */ 806 static void check_section(const char *modname, struct elf_info *elf, 807 Elf_Shdr *sechdr) 808 { 809 const char *sec = sech_name(elf, sechdr); 810 811 if (sechdr->sh_type == SHT_PROGBITS && 812 !(sechdr->sh_flags & SHF_ALLOC) && 813 !match(sec, section_white_list)) { 814 warn("%s (%s): unexpected non-allocatable section.\n" 815 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n" 816 "Note that for example <linux/init.h> contains\n" 817 "section definitions for use in .S files.\n\n", 818 modname, sec); 819 } 820 } 821 822 823 824 #define ALL_INIT_DATA_SECTIONS \ 825 ".init.setup$", ".init.rodata$", \ 826 ".devinit.rodata$", ".cpuinit.rodata$", ".meminit.rodata$" \ 827 ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$" 828 #define ALL_EXIT_DATA_SECTIONS \ 829 ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$" 830 831 #define ALL_INIT_TEXT_SECTIONS \ 832 ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$" 833 #define ALL_EXIT_TEXT_SECTIONS \ 834 ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$" 835 836 #define ALL_XXXINIT_SECTIONS DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, \ 837 MEM_INIT_SECTIONS 838 #define ALL_XXXEXIT_SECTIONS DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, \ 839 MEM_EXIT_SECTIONS 840 841 #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS 842 #define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS 843 844 #define DATA_SECTIONS ".data$", ".data.rel$" 845 #define TEXT_SECTIONS ".text$" 846 847 #define INIT_SECTIONS ".init.*" 848 #define DEV_INIT_SECTIONS ".devinit.*" 849 #define CPU_INIT_SECTIONS ".cpuinit.*" 850 #define MEM_INIT_SECTIONS ".meminit.*" 851 852 #define EXIT_SECTIONS ".exit.*" 853 #define DEV_EXIT_SECTIONS ".devexit.*" 854 #define CPU_EXIT_SECTIONS ".cpuexit.*" 855 #define MEM_EXIT_SECTIONS ".memexit.*" 856 857 /* init data sections */ 858 static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL }; 859 860 /* all init sections */ 861 static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL }; 862 863 /* All init and exit sections (code + data) */ 864 static const char *init_exit_sections[] = 865 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }; 866 867 /* data section */ 868 static const char *data_sections[] = { DATA_SECTIONS, NULL }; 869 870 871 /* symbols in .data that may refer to init/exit sections */ 872 #define DEFAULT_SYMBOL_WHITE_LIST \ 873 "*driver", \ 874 "*_template", /* scsi uses *_template a lot */ \ 875 "*_timer", /* arm uses ops structures named _timer a lot */ \ 876 "*_sht", /* scsi also used *_sht to some extent */ \ 877 "*_ops", \ 878 "*_probe", \ 879 "*_probe_one", \ 880 "*_console" 881 882 static const char *head_sections[] = { ".head.text*", NULL }; 883 static const char *linker_symbols[] = 884 { "__init_begin", "_sinittext", "_einittext", NULL }; 885 886 enum mismatch { 887 TEXT_TO_ANY_INIT, 888 DATA_TO_ANY_INIT, 889 TEXT_TO_ANY_EXIT, 890 DATA_TO_ANY_EXIT, 891 XXXINIT_TO_SOME_INIT, 892 XXXEXIT_TO_SOME_EXIT, 893 ANY_INIT_TO_ANY_EXIT, 894 ANY_EXIT_TO_ANY_INIT, 895 EXPORT_TO_INIT_EXIT, 896 }; 897 898 struct sectioncheck { 899 const char *fromsec[20]; 900 const char *tosec[20]; 901 enum mismatch mismatch; 902 const char *symbol_white_list[20]; 903 }; 904 905 const struct sectioncheck sectioncheck[] = { 906 /* Do not reference init/exit code/data from 907 * normal code and data 908 */ 909 { 910 .fromsec = { TEXT_SECTIONS, NULL }, 911 .tosec = { ALL_INIT_SECTIONS, NULL }, 912 .mismatch = TEXT_TO_ANY_INIT, 913 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 914 }, 915 { 916 .fromsec = { DATA_SECTIONS, NULL }, 917 .tosec = { ALL_XXXINIT_SECTIONS, NULL }, 918 .mismatch = DATA_TO_ANY_INIT, 919 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 920 }, 921 { 922 .fromsec = { DATA_SECTIONS, NULL }, 923 .tosec = { INIT_SECTIONS, NULL }, 924 .mismatch = DATA_TO_ANY_INIT, 925 .symbol_white_list = { 926 "*_template", "*_timer", "*_sht", "*_ops", 927 "*_probe", "*_probe_one", "*_console", NULL 928 }, 929 }, 930 { 931 .fromsec = { TEXT_SECTIONS, NULL }, 932 .tosec = { ALL_EXIT_SECTIONS, NULL }, 933 .mismatch = TEXT_TO_ANY_EXIT, 934 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 935 }, 936 { 937 .fromsec = { DATA_SECTIONS, NULL }, 938 .tosec = { ALL_EXIT_SECTIONS, NULL }, 939 .mismatch = DATA_TO_ANY_EXIT, 940 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 941 }, 942 /* Do not reference init code/data from devinit/cpuinit/meminit code/data */ 943 { 944 .fromsec = { ALL_XXXINIT_SECTIONS, NULL }, 945 .tosec = { INIT_SECTIONS, NULL }, 946 .mismatch = XXXINIT_TO_SOME_INIT, 947 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 948 }, 949 /* Do not reference cpuinit code/data from meminit code/data */ 950 { 951 .fromsec = { MEM_INIT_SECTIONS, NULL }, 952 .tosec = { CPU_INIT_SECTIONS, NULL }, 953 .mismatch = XXXINIT_TO_SOME_INIT, 954 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 955 }, 956 /* Do not reference meminit code/data from cpuinit code/data */ 957 { 958 .fromsec = { CPU_INIT_SECTIONS, NULL }, 959 .tosec = { MEM_INIT_SECTIONS, NULL }, 960 .mismatch = XXXINIT_TO_SOME_INIT, 961 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 962 }, 963 /* Do not reference exit code/data from devexit/cpuexit/memexit code/data */ 964 { 965 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL }, 966 .tosec = { EXIT_SECTIONS, NULL }, 967 .mismatch = XXXEXIT_TO_SOME_EXIT, 968 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 969 }, 970 /* Do not reference cpuexit code/data from memexit code/data */ 971 { 972 .fromsec = { MEM_EXIT_SECTIONS, NULL }, 973 .tosec = { CPU_EXIT_SECTIONS, NULL }, 974 .mismatch = XXXEXIT_TO_SOME_EXIT, 975 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 976 }, 977 /* Do not reference memexit code/data from cpuexit code/data */ 978 { 979 .fromsec = { CPU_EXIT_SECTIONS, NULL }, 980 .tosec = { MEM_EXIT_SECTIONS, NULL }, 981 .mismatch = XXXEXIT_TO_SOME_EXIT, 982 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 983 }, 984 /* Do not use exit code/data from init code */ 985 { 986 .fromsec = { ALL_INIT_SECTIONS, NULL }, 987 .tosec = { ALL_EXIT_SECTIONS, NULL }, 988 .mismatch = ANY_INIT_TO_ANY_EXIT, 989 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 990 }, 991 /* Do not use init code/data from exit code */ 992 { 993 .fromsec = { ALL_EXIT_SECTIONS, NULL }, 994 .tosec = { ALL_INIT_SECTIONS, NULL }, 995 .mismatch = ANY_EXIT_TO_ANY_INIT, 996 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 997 }, 998 /* Do not export init/exit functions or data */ 999 { 1000 .fromsec = { "__ksymtab*", NULL }, 1001 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL }, 1002 .mismatch = EXPORT_TO_INIT_EXIT, 1003 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 1004 } 1005 }; 1006 1007 static const struct sectioncheck *section_mismatch( 1008 const char *fromsec, const char *tosec) 1009 { 1010 int i; 1011 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck); 1012 const struct sectioncheck *check = §ioncheck[0]; 1013 1014 for (i = 0; i < elems; i++) { 1015 if (match(fromsec, check->fromsec) && 1016 match(tosec, check->tosec)) 1017 return check; 1018 check++; 1019 } 1020 return NULL; 1021 } 1022 1023 /** 1024 * Whitelist to allow certain references to pass with no warning. 1025 * 1026 * Pattern 1: 1027 * If a module parameter is declared __initdata and permissions=0 1028 * then this is legal despite the warning generated. 1029 * We cannot see value of permissions here, so just ignore 1030 * this pattern. 1031 * The pattern is identified by: 1032 * tosec = .init.data 1033 * fromsec = .data* 1034 * atsym =__param* 1035 * 1036 * Pattern 2: 1037 * Many drivers utilise a *driver container with references to 1038 * add, remove, probe functions etc. 1039 * These functions may often be marked __devinit and we do not want to 1040 * warn here. 1041 * the pattern is identified by: 1042 * tosec = init or exit section 1043 * fromsec = data section 1044 * atsym = *driver, *_template, *_sht, *_ops, *_probe, 1045 * *probe_one, *_console, *_timer 1046 * 1047 * Pattern 3: 1048 * Whitelist all references from .head.text to any init section 1049 * 1050 * Pattern 4: 1051 * Some symbols belong to init section but still it is ok to reference 1052 * these from non-init sections as these symbols don't have any memory 1053 * allocated for them and symbol address and value are same. So even 1054 * if init section is freed, its ok to reference those symbols. 1055 * For ex. symbols marking the init section boundaries. 1056 * This pattern is identified by 1057 * refsymname = __init_begin, _sinittext, _einittext 1058 * 1059 **/ 1060 static int secref_whitelist(const struct sectioncheck *mismatch, 1061 const char *fromsec, const char *fromsym, 1062 const char *tosec, const char *tosym) 1063 { 1064 /* Check for pattern 1 */ 1065 if (match(tosec, init_data_sections) && 1066 match(fromsec, data_sections) && 1067 (strncmp(fromsym, "__param", strlen("__param")) == 0)) 1068 return 0; 1069 1070 /* Check for pattern 2 */ 1071 if (match(tosec, init_exit_sections) && 1072 match(fromsec, data_sections) && 1073 match(fromsym, mismatch->symbol_white_list)) 1074 return 0; 1075 1076 /* Check for pattern 3 */ 1077 if (match(fromsec, head_sections) && 1078 match(tosec, init_sections)) 1079 return 0; 1080 1081 /* Check for pattern 4 */ 1082 if (match(tosym, linker_symbols)) 1083 return 0; 1084 1085 return 1; 1086 } 1087 1088 /** 1089 * Find symbol based on relocation record info. 1090 * In some cases the symbol supplied is a valid symbol so 1091 * return refsym. If st_name != 0 we assume this is a valid symbol. 1092 * In other cases the symbol needs to be looked up in the symbol table 1093 * based on section and address. 1094 * **/ 1095 static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr, 1096 Elf_Sym *relsym) 1097 { 1098 Elf_Sym *sym; 1099 Elf_Sym *near = NULL; 1100 Elf64_Sword distance = 20; 1101 Elf64_Sword d; 1102 unsigned int relsym_secindex; 1103 1104 if (relsym->st_name != 0) 1105 return relsym; 1106 1107 relsym_secindex = get_secindex(elf, relsym); 1108 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { 1109 if (get_secindex(elf, sym) != relsym_secindex) 1110 continue; 1111 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION) 1112 continue; 1113 if (sym->st_value == addr) 1114 return sym; 1115 /* Find a symbol nearby - addr are maybe negative */ 1116 d = sym->st_value - addr; 1117 if (d < 0) 1118 d = addr - sym->st_value; 1119 if (d < distance) { 1120 distance = d; 1121 near = sym; 1122 } 1123 } 1124 /* We need a close match */ 1125 if (distance < 20) 1126 return near; 1127 else 1128 return NULL; 1129 } 1130 1131 static inline int is_arm_mapping_symbol(const char *str) 1132 { 1133 return str[0] == '$' && strchr("atd", str[1]) 1134 && (str[2] == '\0' || str[2] == '.'); 1135 } 1136 1137 /* 1138 * If there's no name there, ignore it; likewise, ignore it if it's 1139 * one of the magic symbols emitted used by current ARM tools. 1140 * 1141 * Otherwise if find_symbols_between() returns those symbols, they'll 1142 * fail the whitelist tests and cause lots of false alarms ... fixable 1143 * only by merging __exit and __init sections into __text, bloating 1144 * the kernel (which is especially evil on embedded platforms). 1145 */ 1146 static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym) 1147 { 1148 const char *name = elf->strtab + sym->st_name; 1149 1150 if (!name || !strlen(name)) 1151 return 0; 1152 return !is_arm_mapping_symbol(name); 1153 } 1154 1155 /* 1156 * Find symbols before or equal addr and after addr - in the section sec. 1157 * If we find two symbols with equal offset prefer one with a valid name. 1158 * The ELF format may have a better way to detect what type of symbol 1159 * it is, but this works for now. 1160 **/ 1161 static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr, 1162 const char *sec) 1163 { 1164 Elf_Sym *sym; 1165 Elf_Sym *near = NULL; 1166 Elf_Addr distance = ~0; 1167 1168 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { 1169 const char *symsec; 1170 1171 if (is_shndx_special(sym->st_shndx)) 1172 continue; 1173 symsec = sec_name(elf, get_secindex(elf, sym)); 1174 if (strcmp(symsec, sec) != 0) 1175 continue; 1176 if (!is_valid_name(elf, sym)) 1177 continue; 1178 if (sym->st_value <= addr) { 1179 if ((addr - sym->st_value) < distance) { 1180 distance = addr - sym->st_value; 1181 near = sym; 1182 } else if ((addr - sym->st_value) == distance) { 1183 near = sym; 1184 } 1185 } 1186 } 1187 return near; 1188 } 1189 1190 /* 1191 * Convert a section name to the function/data attribute 1192 * .init.text => __init 1193 * .cpuinit.data => __cpudata 1194 * .memexitconst => __memconst 1195 * etc. 1196 */ 1197 static char *sec2annotation(const char *s) 1198 { 1199 if (match(s, init_exit_sections)) { 1200 char *p = malloc(20); 1201 char *r = p; 1202 1203 *p++ = '_'; 1204 *p++ = '_'; 1205 if (*s == '.') 1206 s++; 1207 while (*s && *s != '.') 1208 *p++ = *s++; 1209 *p = '\0'; 1210 if (*s == '.') 1211 s++; 1212 if (strstr(s, "rodata") != NULL) 1213 strcat(p, "const "); 1214 else if (strstr(s, "data") != NULL) 1215 strcat(p, "data "); 1216 else 1217 strcat(p, " "); 1218 return r; /* we leak her but we do not care */ 1219 } else { 1220 return ""; 1221 } 1222 } 1223 1224 static int is_function(Elf_Sym *sym) 1225 { 1226 if (sym) 1227 return ELF_ST_TYPE(sym->st_info) == STT_FUNC; 1228 else 1229 return -1; 1230 } 1231 1232 /* 1233 * Print a warning about a section mismatch. 1234 * Try to find symbols near it so user can find it. 1235 * Check whitelist before warning - it may be a false positive. 1236 */ 1237 static void report_sec_mismatch(const char *modname, 1238 const struct sectioncheck *mismatch, 1239 const char *fromsec, 1240 unsigned long long fromaddr, 1241 const char *fromsym, 1242 int from_is_func, 1243 const char *tosec, const char *tosym, 1244 int to_is_func) 1245 { 1246 const char *from, *from_p; 1247 const char *to, *to_p; 1248 char *prl_from; 1249 char *prl_to; 1250 1251 switch (from_is_func) { 1252 case 0: from = "variable"; from_p = ""; break; 1253 case 1: from = "function"; from_p = "()"; break; 1254 default: from = "(unknown reference)"; from_p = ""; break; 1255 } 1256 switch (to_is_func) { 1257 case 0: to = "variable"; to_p = ""; break; 1258 case 1: to = "function"; to_p = "()"; break; 1259 default: to = "(unknown reference)"; to_p = ""; break; 1260 } 1261 1262 sec_mismatch_count++; 1263 if (!sec_mismatch_verbose) 1264 return; 1265 1266 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s " 1267 "to the %s %s:%s%s\n", 1268 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec, 1269 tosym, to_p); 1270 1271 switch (mismatch->mismatch) { 1272 case TEXT_TO_ANY_INIT: 1273 prl_from = sec2annotation(fromsec); 1274 prl_to = sec2annotation(tosec); 1275 fprintf(stderr, 1276 "The function %s%s() references\n" 1277 "the %s %s%s%s.\n" 1278 "This is often because %s lacks a %s\n" 1279 "annotation or the annotation of %s is wrong.\n", 1280 prl_from, fromsym, 1281 to, prl_to, tosym, to_p, 1282 fromsym, prl_to, tosym); 1283 free(prl_from); 1284 free(prl_to); 1285 break; 1286 case DATA_TO_ANY_INIT: { 1287 prl_to = sec2annotation(tosec); 1288 const char *const *s = mismatch->symbol_white_list; 1289 fprintf(stderr, 1290 "The variable %s references\n" 1291 "the %s %s%s%s\n" 1292 "If the reference is valid then annotate the\n" 1293 "variable with __init* or __refdata (see linux/init.h) " 1294 "or name the variable:\n", 1295 fromsym, to, prl_to, tosym, to_p); 1296 while (*s) 1297 fprintf(stderr, "%s, ", *s++); 1298 fprintf(stderr, "\n"); 1299 free(prl_to); 1300 break; 1301 } 1302 case TEXT_TO_ANY_EXIT: 1303 prl_to = sec2annotation(tosec); 1304 fprintf(stderr, 1305 "The function %s() references a %s in an exit section.\n" 1306 "Often the %s %s%s has valid usage outside the exit section\n" 1307 "and the fix is to remove the %sannotation of %s.\n", 1308 fromsym, to, to, tosym, to_p, prl_to, tosym); 1309 free(prl_to); 1310 break; 1311 case DATA_TO_ANY_EXIT: { 1312 prl_to = sec2annotation(tosec); 1313 const char *const *s = mismatch->symbol_white_list; 1314 fprintf(stderr, 1315 "The variable %s references\n" 1316 "the %s %s%s%s\n" 1317 "If the reference is valid then annotate the\n" 1318 "variable with __exit* (see linux/init.h) or " 1319 "name the variable:\n", 1320 fromsym, to, prl_to, tosym, to_p); 1321 while (*s) 1322 fprintf(stderr, "%s, ", *s++); 1323 fprintf(stderr, "\n"); 1324 free(prl_to); 1325 break; 1326 } 1327 case XXXINIT_TO_SOME_INIT: 1328 case XXXEXIT_TO_SOME_EXIT: 1329 prl_from = sec2annotation(fromsec); 1330 prl_to = sec2annotation(tosec); 1331 fprintf(stderr, 1332 "The %s %s%s%s references\n" 1333 "a %s %s%s%s.\n" 1334 "If %s is only used by %s then\n" 1335 "annotate %s with a matching annotation.\n", 1336 from, prl_from, fromsym, from_p, 1337 to, prl_to, tosym, to_p, 1338 tosym, fromsym, tosym); 1339 free(prl_from); 1340 free(prl_to); 1341 break; 1342 case ANY_INIT_TO_ANY_EXIT: 1343 prl_from = sec2annotation(fromsec); 1344 prl_to = sec2annotation(tosec); 1345 fprintf(stderr, 1346 "The %s %s%s%s references\n" 1347 "a %s %s%s%s.\n" 1348 "This is often seen when error handling " 1349 "in the init function\n" 1350 "uses functionality in the exit path.\n" 1351 "The fix is often to remove the %sannotation of\n" 1352 "%s%s so it may be used outside an exit section.\n", 1353 from, prl_from, fromsym, from_p, 1354 to, prl_to, tosym, to_p, 1355 sec2annotation(tosec), tosym, to_p); 1356 free(prl_from); 1357 free(prl_to); 1358 break; 1359 case ANY_EXIT_TO_ANY_INIT: 1360 prl_from = sec2annotation(fromsec); 1361 prl_to = sec2annotation(tosec); 1362 fprintf(stderr, 1363 "The %s %s%s%s references\n" 1364 "a %s %s%s%s.\n" 1365 "This is often seen when error handling " 1366 "in the exit function\n" 1367 "uses functionality in the init path.\n" 1368 "The fix is often to remove the %sannotation of\n" 1369 "%s%s so it may be used outside an init section.\n", 1370 from, prl_from, fromsym, from_p, 1371 to, prl_to, tosym, to_p, 1372 prl_to, tosym, to_p); 1373 free(prl_from); 1374 free(prl_to); 1375 break; 1376 case EXPORT_TO_INIT_EXIT: 1377 prl_to = sec2annotation(tosec); 1378 fprintf(stderr, 1379 "The symbol %s is exported and annotated %s\n" 1380 "Fix this by removing the %sannotation of %s " 1381 "or drop the export.\n", 1382 tosym, prl_to, prl_to, tosym); 1383 free(prl_to); 1384 break; 1385 } 1386 fprintf(stderr, "\n"); 1387 } 1388 1389 static void check_section_mismatch(const char *modname, struct elf_info *elf, 1390 Elf_Rela *r, Elf_Sym *sym, const char *fromsec) 1391 { 1392 const char *tosec; 1393 const struct sectioncheck *mismatch; 1394 1395 tosec = sec_name(elf, get_secindex(elf, sym)); 1396 mismatch = section_mismatch(fromsec, tosec); 1397 if (mismatch) { 1398 Elf_Sym *to; 1399 Elf_Sym *from; 1400 const char *tosym; 1401 const char *fromsym; 1402 1403 from = find_elf_symbol2(elf, r->r_offset, fromsec); 1404 fromsym = sym_name(elf, from); 1405 to = find_elf_symbol(elf, r->r_addend, sym); 1406 tosym = sym_name(elf, to); 1407 1408 /* check whitelist - we may ignore it */ 1409 if (secref_whitelist(mismatch, 1410 fromsec, fromsym, tosec, tosym)) { 1411 report_sec_mismatch(modname, mismatch, 1412 fromsec, r->r_offset, fromsym, 1413 is_function(from), tosec, tosym, 1414 is_function(to)); 1415 } 1416 } 1417 } 1418 1419 static unsigned int *reloc_location(struct elf_info *elf, 1420 Elf_Shdr *sechdr, Elf_Rela *r) 1421 { 1422 Elf_Shdr *sechdrs = elf->sechdrs; 1423 int section = shndx2secindex(sechdr->sh_info); 1424 1425 return (void *)elf->hdr + sechdrs[section].sh_offset + 1426 r->r_offset - sechdrs[section].sh_addr; 1427 } 1428 1429 static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1430 { 1431 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1432 unsigned int *location = reloc_location(elf, sechdr, r); 1433 1434 switch (r_typ) { 1435 case R_386_32: 1436 r->r_addend = TO_NATIVE(*location); 1437 break; 1438 case R_386_PC32: 1439 r->r_addend = TO_NATIVE(*location) + 4; 1440 /* For CONFIG_RELOCATABLE=y */ 1441 if (elf->hdr->e_type == ET_EXEC) 1442 r->r_addend += r->r_offset; 1443 break; 1444 } 1445 return 0; 1446 } 1447 1448 static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1449 { 1450 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1451 1452 switch (r_typ) { 1453 case R_ARM_ABS32: 1454 /* From ARM ABI: (S + A) | T */ 1455 r->r_addend = (int)(long) 1456 (elf->symtab_start + ELF_R_SYM(r->r_info)); 1457 break; 1458 case R_ARM_PC24: 1459 /* From ARM ABI: ((S + A) | T) - P */ 1460 r->r_addend = (int)(long)(elf->hdr + 1461 sechdr->sh_offset + 1462 (r->r_offset - sechdr->sh_addr)); 1463 break; 1464 default: 1465 return 1; 1466 } 1467 return 0; 1468 } 1469 1470 static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1471 { 1472 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1473 unsigned int *location = reloc_location(elf, sechdr, r); 1474 unsigned int inst; 1475 1476 if (r_typ == R_MIPS_HI16) 1477 return 1; /* skip this */ 1478 inst = TO_NATIVE(*location); 1479 switch (r_typ) { 1480 case R_MIPS_LO16: 1481 r->r_addend = inst & 0xffff; 1482 break; 1483 case R_MIPS_26: 1484 r->r_addend = (inst & 0x03ffffff) << 2; 1485 break; 1486 case R_MIPS_32: 1487 r->r_addend = inst; 1488 break; 1489 } 1490 return 0; 1491 } 1492 1493 static void section_rela(const char *modname, struct elf_info *elf, 1494 Elf_Shdr *sechdr) 1495 { 1496 Elf_Sym *sym; 1497 Elf_Rela *rela; 1498 Elf_Rela r; 1499 unsigned int r_sym; 1500 const char *fromsec; 1501 1502 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset; 1503 Elf_Rela *stop = (void *)start + sechdr->sh_size; 1504 1505 fromsec = sech_name(elf, sechdr); 1506 fromsec += strlen(".rela"); 1507 /* if from section (name) is know good then skip it */ 1508 if (match(fromsec, section_white_list)) 1509 return; 1510 1511 for (rela = start; rela < stop; rela++) { 1512 r.r_offset = TO_NATIVE(rela->r_offset); 1513 #if KERNEL_ELFCLASS == ELFCLASS64 1514 if (elf->hdr->e_machine == EM_MIPS) { 1515 unsigned int r_typ; 1516 r_sym = ELF64_MIPS_R_SYM(rela->r_info); 1517 r_sym = TO_NATIVE(r_sym); 1518 r_typ = ELF64_MIPS_R_TYPE(rela->r_info); 1519 r.r_info = ELF64_R_INFO(r_sym, r_typ); 1520 } else { 1521 r.r_info = TO_NATIVE(rela->r_info); 1522 r_sym = ELF_R_SYM(r.r_info); 1523 } 1524 #else 1525 r.r_info = TO_NATIVE(rela->r_info); 1526 r_sym = ELF_R_SYM(r.r_info); 1527 #endif 1528 r.r_addend = TO_NATIVE(rela->r_addend); 1529 sym = elf->symtab_start + r_sym; 1530 /* Skip special sections */ 1531 if (is_shndx_special(sym->st_shndx)) 1532 continue; 1533 check_section_mismatch(modname, elf, &r, sym, fromsec); 1534 } 1535 } 1536 1537 static void section_rel(const char *modname, struct elf_info *elf, 1538 Elf_Shdr *sechdr) 1539 { 1540 Elf_Sym *sym; 1541 Elf_Rel *rel; 1542 Elf_Rela r; 1543 unsigned int r_sym; 1544 const char *fromsec; 1545 1546 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset; 1547 Elf_Rel *stop = (void *)start + sechdr->sh_size; 1548 1549 fromsec = sech_name(elf, sechdr); 1550 fromsec += strlen(".rel"); 1551 /* if from section (name) is know good then skip it */ 1552 if (match(fromsec, section_white_list)) 1553 return; 1554 1555 for (rel = start; rel < stop; rel++) { 1556 r.r_offset = TO_NATIVE(rel->r_offset); 1557 #if KERNEL_ELFCLASS == ELFCLASS64 1558 if (elf->hdr->e_machine == EM_MIPS) { 1559 unsigned int r_typ; 1560 r_sym = ELF64_MIPS_R_SYM(rel->r_info); 1561 r_sym = TO_NATIVE(r_sym); 1562 r_typ = ELF64_MIPS_R_TYPE(rel->r_info); 1563 r.r_info = ELF64_R_INFO(r_sym, r_typ); 1564 } else { 1565 r.r_info = TO_NATIVE(rel->r_info); 1566 r_sym = ELF_R_SYM(r.r_info); 1567 } 1568 #else 1569 r.r_info = TO_NATIVE(rel->r_info); 1570 r_sym = ELF_R_SYM(r.r_info); 1571 #endif 1572 r.r_addend = 0; 1573 switch (elf->hdr->e_machine) { 1574 case EM_386: 1575 if (addend_386_rel(elf, sechdr, &r)) 1576 continue; 1577 break; 1578 case EM_ARM: 1579 if (addend_arm_rel(elf, sechdr, &r)) 1580 continue; 1581 break; 1582 case EM_MIPS: 1583 if (addend_mips_rel(elf, sechdr, &r)) 1584 continue; 1585 break; 1586 } 1587 sym = elf->symtab_start + r_sym; 1588 /* Skip special sections */ 1589 if (is_shndx_special(sym->st_shndx)) 1590 continue; 1591 check_section_mismatch(modname, elf, &r, sym, fromsec); 1592 } 1593 } 1594 1595 /** 1596 * A module includes a number of sections that are discarded 1597 * either when loaded or when used as built-in. 1598 * For loaded modules all functions marked __init and all data 1599 * marked __initdata will be discarded when the module has been intialized. 1600 * Likewise for modules used built-in the sections marked __exit 1601 * are discarded because __exit marked function are supposed to be called 1602 * only when a module is unloaded which never happens for built-in modules. 1603 * The check_sec_ref() function traverses all relocation records 1604 * to find all references to a section that reference a section that will 1605 * be discarded and warns about it. 1606 **/ 1607 static void check_sec_ref(struct module *mod, const char *modname, 1608 struct elf_info *elf) 1609 { 1610 int i; 1611 Elf_Shdr *sechdrs = elf->sechdrs; 1612 1613 /* Walk through all sections */ 1614 for (i = 0; i < elf->num_sections; i++) { 1615 check_section(modname, elf, &elf->sechdrs[i]); 1616 /* We want to process only relocation sections and not .init */ 1617 if (sechdrs[i].sh_type == SHT_RELA) 1618 section_rela(modname, elf, &elf->sechdrs[i]); 1619 else if (sechdrs[i].sh_type == SHT_REL) 1620 section_rel(modname, elf, &elf->sechdrs[i]); 1621 } 1622 } 1623 1624 static void read_symbols(char *modname) 1625 { 1626 const char *symname; 1627 char *version; 1628 char *license; 1629 struct module *mod; 1630 struct elf_info info = { }; 1631 Elf_Sym *sym; 1632 1633 if (!parse_elf(&info, modname)) 1634 return; 1635 1636 mod = new_module(modname); 1637 1638 /* When there's no vmlinux, don't print warnings about 1639 * unresolved symbols (since there'll be too many ;) */ 1640 if (is_vmlinux(modname)) { 1641 have_vmlinux = 1; 1642 mod->skip = 1; 1643 } 1644 1645 license = get_modinfo(info.modinfo, info.modinfo_len, "license"); 1646 if (info.modinfo && !license && !is_vmlinux(modname)) 1647 warn("modpost: missing MODULE_LICENSE() in %s\n" 1648 "see include/linux/module.h for " 1649 "more information\n", modname); 1650 while (license) { 1651 if (license_is_gpl_compatible(license)) 1652 mod->gpl_compatible = 1; 1653 else { 1654 mod->gpl_compatible = 0; 1655 break; 1656 } 1657 license = get_next_modinfo(info.modinfo, info.modinfo_len, 1658 "license", license); 1659 } 1660 1661 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { 1662 symname = info.strtab + sym->st_name; 1663 1664 handle_modversions(mod, &info, sym, symname); 1665 handle_moddevtable(mod, &info, sym, symname); 1666 } 1667 if (!is_vmlinux(modname) || 1668 (is_vmlinux(modname) && vmlinux_section_warnings)) 1669 check_sec_ref(mod, modname, &info); 1670 1671 version = get_modinfo(info.modinfo, info.modinfo_len, "version"); 1672 if (version) 1673 maybe_frob_rcs_version(modname, version, info.modinfo, 1674 version - (char *)info.hdr); 1675 if (version || (all_versions && !is_vmlinux(modname))) 1676 get_src_version(modname, mod->srcversion, 1677 sizeof(mod->srcversion)-1); 1678 1679 parse_elf_finish(&info); 1680 1681 /* Our trick to get versioning for module struct etc. - it's 1682 * never passed as an argument to an exported function, so 1683 * the automatic versioning doesn't pick it up, but it's really 1684 * important anyhow */ 1685 if (modversions) 1686 mod->unres = alloc_symbol("module_layout", 0, mod->unres); 1687 } 1688 1689 #define SZ 500 1690 1691 /* We first write the generated file into memory using the 1692 * following helper, then compare to the file on disk and 1693 * only update the later if anything changed */ 1694 1695 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf, 1696 const char *fmt, ...) 1697 { 1698 char tmp[SZ]; 1699 int len; 1700 va_list ap; 1701 1702 va_start(ap, fmt); 1703 len = vsnprintf(tmp, SZ, fmt, ap); 1704 buf_write(buf, tmp, len); 1705 va_end(ap); 1706 } 1707 1708 void buf_write(struct buffer *buf, const char *s, int len) 1709 { 1710 if (buf->size - buf->pos < len) { 1711 buf->size += len + SZ; 1712 buf->p = realloc(buf->p, buf->size); 1713 } 1714 strncpy(buf->p + buf->pos, s, len); 1715 buf->pos += len; 1716 } 1717 1718 static void check_for_gpl_usage(enum export exp, const char *m, const char *s) 1719 { 1720 const char *e = is_vmlinux(m) ?"":".ko"; 1721 1722 switch (exp) { 1723 case export_gpl: 1724 fatal("modpost: GPL-incompatible module %s%s " 1725 "uses GPL-only symbol '%s'\n", m, e, s); 1726 break; 1727 case export_unused_gpl: 1728 fatal("modpost: GPL-incompatible module %s%s " 1729 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s); 1730 break; 1731 case export_gpl_future: 1732 warn("modpost: GPL-incompatible module %s%s " 1733 "uses future GPL-only symbol '%s'\n", m, e, s); 1734 break; 1735 case export_plain: 1736 case export_unused: 1737 case export_unknown: 1738 /* ignore */ 1739 break; 1740 } 1741 } 1742 1743 static void check_for_unused(enum export exp, const char *m, const char *s) 1744 { 1745 const char *e = is_vmlinux(m) ?"":".ko"; 1746 1747 switch (exp) { 1748 case export_unused: 1749 case export_unused_gpl: 1750 warn("modpost: module %s%s " 1751 "uses symbol '%s' marked UNUSED\n", m, e, s); 1752 break; 1753 default: 1754 /* ignore */ 1755 break; 1756 } 1757 } 1758 1759 static void check_exports(struct module *mod) 1760 { 1761 struct symbol *s, *exp; 1762 1763 for (s = mod->unres; s; s = s->next) { 1764 const char *basename; 1765 exp = find_symbol(s->name); 1766 if (!exp || exp->module == mod) 1767 continue; 1768 basename = strrchr(mod->name, '/'); 1769 if (basename) 1770 basename++; 1771 else 1772 basename = mod->name; 1773 if (!mod->gpl_compatible) 1774 check_for_gpl_usage(exp->export, basename, exp->name); 1775 check_for_unused(exp->export, basename, exp->name); 1776 } 1777 } 1778 1779 /** 1780 * Header for the generated file 1781 **/ 1782 static void add_header(struct buffer *b, struct module *mod) 1783 { 1784 buf_printf(b, "#include <linux/module.h>\n"); 1785 buf_printf(b, "#include <linux/vermagic.h>\n"); 1786 buf_printf(b, "#include <linux/compiler.h>\n"); 1787 buf_printf(b, "\n"); 1788 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n"); 1789 buf_printf(b, "\n"); 1790 buf_printf(b, "struct module __this_module\n"); 1791 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n"); 1792 buf_printf(b, " .name = KBUILD_MODNAME,\n"); 1793 if (mod->has_init) 1794 buf_printf(b, " .init = init_module,\n"); 1795 if (mod->has_cleanup) 1796 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n" 1797 " .exit = cleanup_module,\n" 1798 "#endif\n"); 1799 buf_printf(b, " .arch = MODULE_ARCH_INIT,\n"); 1800 buf_printf(b, "};\n"); 1801 } 1802 1803 static void add_staging_flag(struct buffer *b, const char *name) 1804 { 1805 static const char *staging_dir = "drivers/staging"; 1806 1807 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0) 1808 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); 1809 } 1810 1811 /** 1812 * Record CRCs for unresolved symbols 1813 **/ 1814 static int add_versions(struct buffer *b, struct module *mod) 1815 { 1816 struct symbol *s, *exp; 1817 int err = 0; 1818 1819 for (s = mod->unres; s; s = s->next) { 1820 exp = find_symbol(s->name); 1821 if (!exp || exp->module == mod) { 1822 if (have_vmlinux && !s->weak) { 1823 if (warn_unresolved) { 1824 warn("\"%s\" [%s.ko] undefined!\n", 1825 s->name, mod->name); 1826 } else { 1827 merror("\"%s\" [%s.ko] undefined!\n", 1828 s->name, mod->name); 1829 err = 1; 1830 } 1831 } 1832 continue; 1833 } 1834 s->module = exp->module; 1835 s->crc_valid = exp->crc_valid; 1836 s->crc = exp->crc; 1837 } 1838 1839 if (!modversions) 1840 return err; 1841 1842 buf_printf(b, "\n"); 1843 buf_printf(b, "static const struct modversion_info ____versions[]\n"); 1844 buf_printf(b, "__used\n"); 1845 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n"); 1846 1847 for (s = mod->unres; s; s = s->next) { 1848 if (!s->module) 1849 continue; 1850 if (!s->crc_valid) { 1851 warn("\"%s\" [%s.ko] has no CRC!\n", 1852 s->name, mod->name); 1853 continue; 1854 } 1855 buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name); 1856 } 1857 1858 buf_printf(b, "};\n"); 1859 1860 return err; 1861 } 1862 1863 static void add_depends(struct buffer *b, struct module *mod, 1864 struct module *modules) 1865 { 1866 struct symbol *s; 1867 struct module *m; 1868 int first = 1; 1869 1870 for (m = modules; m; m = m->next) 1871 m->seen = is_vmlinux(m->name); 1872 1873 buf_printf(b, "\n"); 1874 buf_printf(b, "static const char __module_depends[]\n"); 1875 buf_printf(b, "__used\n"); 1876 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n"); 1877 buf_printf(b, "\"depends="); 1878 for (s = mod->unres; s; s = s->next) { 1879 const char *p; 1880 if (!s->module) 1881 continue; 1882 1883 if (s->module->seen) 1884 continue; 1885 1886 s->module->seen = 1; 1887 p = strrchr(s->module->name, '/'); 1888 if (p) 1889 p++; 1890 else 1891 p = s->module->name; 1892 buf_printf(b, "%s%s", first ? "" : ",", p); 1893 first = 0; 1894 } 1895 buf_printf(b, "\";\n"); 1896 } 1897 1898 static void add_srcversion(struct buffer *b, struct module *mod) 1899 { 1900 if (mod->srcversion[0]) { 1901 buf_printf(b, "\n"); 1902 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n", 1903 mod->srcversion); 1904 } 1905 } 1906 1907 static void write_if_changed(struct buffer *b, const char *fname) 1908 { 1909 char *tmp; 1910 FILE *file; 1911 struct stat st; 1912 1913 file = fopen(fname, "r"); 1914 if (!file) 1915 goto write; 1916 1917 if (fstat(fileno(file), &st) < 0) 1918 goto close_write; 1919 1920 if (st.st_size != b->pos) 1921 goto close_write; 1922 1923 tmp = NOFAIL(malloc(b->pos)); 1924 if (fread(tmp, 1, b->pos, file) != b->pos) 1925 goto free_write; 1926 1927 if (memcmp(tmp, b->p, b->pos) != 0) 1928 goto free_write; 1929 1930 free(tmp); 1931 fclose(file); 1932 return; 1933 1934 free_write: 1935 free(tmp); 1936 close_write: 1937 fclose(file); 1938 write: 1939 file = fopen(fname, "w"); 1940 if (!file) { 1941 perror(fname); 1942 exit(1); 1943 } 1944 if (fwrite(b->p, 1, b->pos, file) != b->pos) { 1945 perror(fname); 1946 exit(1); 1947 } 1948 fclose(file); 1949 } 1950 1951 /* parse Module.symvers file. line format: 1952 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something] 1953 **/ 1954 static void read_dump(const char *fname, unsigned int kernel) 1955 { 1956 unsigned long size, pos = 0; 1957 void *file = grab_file(fname, &size); 1958 char *line; 1959 1960 if (!file) 1961 /* No symbol versions, silently ignore */ 1962 return; 1963 1964 while ((line = get_next_line(&pos, file, size))) { 1965 char *symname, *modname, *d, *export, *end; 1966 unsigned int crc; 1967 struct module *mod; 1968 struct symbol *s; 1969 1970 if (!(symname = strchr(line, '\t'))) 1971 goto fail; 1972 *symname++ = '\0'; 1973 if (!(modname = strchr(symname, '\t'))) 1974 goto fail; 1975 *modname++ = '\0'; 1976 if ((export = strchr(modname, '\t')) != NULL) 1977 *export++ = '\0'; 1978 if (export && ((end = strchr(export, '\t')) != NULL)) 1979 *end = '\0'; 1980 crc = strtoul(line, &d, 16); 1981 if (*symname == '\0' || *modname == '\0' || *d != '\0') 1982 goto fail; 1983 mod = find_module(modname); 1984 if (!mod) { 1985 if (is_vmlinux(modname)) 1986 have_vmlinux = 1; 1987 mod = new_module(modname); 1988 mod->skip = 1; 1989 } 1990 s = sym_add_exported(symname, mod, export_no(export)); 1991 s->kernel = kernel; 1992 s->preloaded = 1; 1993 sym_update_crc(symname, mod, crc, export_no(export)); 1994 } 1995 return; 1996 fail: 1997 fatal("parse error in symbol dump file\n"); 1998 } 1999 2000 /* For normal builds always dump all symbols. 2001 * For external modules only dump symbols 2002 * that are not read from kernel Module.symvers. 2003 **/ 2004 static int dump_sym(struct symbol *sym) 2005 { 2006 if (!external_module) 2007 return 1; 2008 if (sym->vmlinux || sym->kernel) 2009 return 0; 2010 return 1; 2011 } 2012 2013 static void write_dump(const char *fname) 2014 { 2015 struct buffer buf = { }; 2016 struct symbol *symbol; 2017 int n; 2018 2019 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) { 2020 symbol = symbolhash[n]; 2021 while (symbol) { 2022 if (dump_sym(symbol)) 2023 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n", 2024 symbol->crc, symbol->name, 2025 symbol->module->name, 2026 export_str(symbol->export)); 2027 symbol = symbol->next; 2028 } 2029 } 2030 write_if_changed(&buf, fname); 2031 } 2032 2033 struct ext_sym_list { 2034 struct ext_sym_list *next; 2035 const char *file; 2036 }; 2037 2038 int main(int argc, char **argv) 2039 { 2040 struct module *mod; 2041 struct buffer buf = { }; 2042 char *kernel_read = NULL, *module_read = NULL; 2043 char *dump_write = NULL; 2044 int opt; 2045 int err; 2046 struct ext_sym_list *extsym_iter; 2047 struct ext_sym_list *extsym_start = NULL; 2048 2049 while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) { 2050 switch (opt) { 2051 case 'i': 2052 kernel_read = optarg; 2053 break; 2054 case 'I': 2055 module_read = optarg; 2056 external_module = 1; 2057 break; 2058 case 'c': 2059 cross_build = 1; 2060 break; 2061 case 'e': 2062 external_module = 1; 2063 extsym_iter = 2064 NOFAIL(malloc(sizeof(*extsym_iter))); 2065 extsym_iter->next = extsym_start; 2066 extsym_iter->file = optarg; 2067 extsym_start = extsym_iter; 2068 break; 2069 case 'm': 2070 modversions = 1; 2071 break; 2072 case 'o': 2073 dump_write = optarg; 2074 break; 2075 case 'a': 2076 all_versions = 1; 2077 break; 2078 case 's': 2079 vmlinux_section_warnings = 0; 2080 break; 2081 case 'S': 2082 sec_mismatch_verbose = 0; 2083 break; 2084 case 'w': 2085 warn_unresolved = 1; 2086 break; 2087 default: 2088 exit(1); 2089 } 2090 } 2091 2092 if (kernel_read) 2093 read_dump(kernel_read, 1); 2094 if (module_read) 2095 read_dump(module_read, 0); 2096 while (extsym_start) { 2097 read_dump(extsym_start->file, 0); 2098 extsym_iter = extsym_start->next; 2099 free(extsym_start); 2100 extsym_start = extsym_iter; 2101 } 2102 2103 while (optind < argc) 2104 read_symbols(argv[optind++]); 2105 2106 for (mod = modules; mod; mod = mod->next) { 2107 if (mod->skip) 2108 continue; 2109 check_exports(mod); 2110 } 2111 2112 err = 0; 2113 2114 for (mod = modules; mod; mod = mod->next) { 2115 char fname[strlen(mod->name) + 10]; 2116 2117 if (mod->skip) 2118 continue; 2119 2120 buf.pos = 0; 2121 2122 add_header(&buf, mod); 2123 add_staging_flag(&buf, mod->name); 2124 err |= add_versions(&buf, mod); 2125 add_depends(&buf, mod, modules); 2126 add_moddevtable(&buf, mod); 2127 add_srcversion(&buf, mod); 2128 2129 sprintf(fname, "%s.mod.c", mod->name); 2130 write_if_changed(&buf, fname); 2131 } 2132 2133 if (dump_write) 2134 write_dump(dump_write); 2135 if (sec_mismatch_count && !sec_mismatch_verbose) 2136 warn("modpost: Found %d section mismatch(es).\n" 2137 "To see full details build your kernel with:\n" 2138 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n", 2139 sec_mismatch_count); 2140 2141 return err; 2142 } 2143