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 <elf.h> 16 #include <fnmatch.h> 17 #include <stdio.h> 18 #include <ctype.h> 19 #include <string.h> 20 #include <limits.h> 21 #include <stdbool.h> 22 #include <errno.h> 23 24 #include <hash.h> 25 #include <hashtable.h> 26 #include <list.h> 27 #include <xalloc.h> 28 #include "modpost.h" 29 #include "../../include/linux/license.h" 30 31 static bool module_enabled; 32 /* Are we using CONFIG_MODVERSIONS? */ 33 static bool modversions; 34 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ 35 static bool all_versions; 36 /* If we are modposting external module set to 1 */ 37 static bool external_module; 38 /* Only warn about unresolved symbols */ 39 static bool warn_unresolved; 40 41 static int sec_mismatch_count; 42 static bool sec_mismatch_warn_only = true; 43 /* Trim EXPORT_SYMBOLs that are unused by in-tree modules */ 44 static bool trim_unused_exports; 45 46 /* ignore missing files */ 47 static bool ignore_missing_files; 48 /* If set to 1, only warn (instead of error) about missing ns imports */ 49 static bool allow_missing_ns_imports; 50 51 static bool error_occurred; 52 53 static bool extra_warn; 54 55 bool target_is_big_endian; 56 bool host_is_big_endian; 57 58 /* 59 * Cut off the warnings when there are too many. This typically occurs when 60 * vmlinux is missing. ('make modules' without building vmlinux.) 61 */ 62 #define MAX_UNRESOLVED_REPORTS 10 63 static unsigned int nr_unresolved; 64 65 /* In kernel, this size is defined in linux/module.h; 66 * here we use Elf_Addr instead of long for covering cross-compile 67 */ 68 69 #define MODULE_NAME_LEN (64 - sizeof(Elf_Addr)) 70 71 void modpost_log(bool is_error, const char *fmt, ...) 72 { 73 va_list arglist; 74 75 if (is_error) { 76 fprintf(stderr, "ERROR: "); 77 error_occurred = true; 78 } else { 79 fprintf(stderr, "WARNING: "); 80 } 81 82 fprintf(stderr, "modpost: "); 83 84 va_start(arglist, fmt); 85 vfprintf(stderr, fmt, arglist); 86 va_end(arglist); 87 } 88 89 static inline bool strends(const char *str, const char *postfix) 90 { 91 if (strlen(str) < strlen(postfix)) 92 return false; 93 94 return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0; 95 } 96 97 char *read_text_file(const char *filename) 98 { 99 struct stat st; 100 size_t nbytes; 101 int fd; 102 char *buf; 103 104 fd = open(filename, O_RDONLY); 105 if (fd < 0) { 106 perror(filename); 107 exit(1); 108 } 109 110 if (fstat(fd, &st) < 0) { 111 perror(filename); 112 exit(1); 113 } 114 115 buf = xmalloc(st.st_size + 1); 116 117 nbytes = st.st_size; 118 119 while (nbytes) { 120 ssize_t bytes_read; 121 122 bytes_read = read(fd, buf, nbytes); 123 if (bytes_read < 0) { 124 perror(filename); 125 exit(1); 126 } 127 128 nbytes -= bytes_read; 129 } 130 buf[st.st_size] = '\0'; 131 132 close(fd); 133 134 return buf; 135 } 136 137 char *get_line(char **stringp) 138 { 139 char *orig = *stringp, *next; 140 141 /* do not return the unwanted extra line at EOF */ 142 if (!orig || *orig == '\0') 143 return NULL; 144 145 /* don't use strsep here, it is not available everywhere */ 146 next = strchr(orig, '\n'); 147 if (next) 148 *next++ = '\0'; 149 150 *stringp = next; 151 152 return orig; 153 } 154 155 /* A list of all modules we processed */ 156 LIST_HEAD(modules); 157 158 static struct module *find_module(const char *filename, const char *modname) 159 { 160 struct module *mod; 161 162 list_for_each_entry(mod, &modules, list) { 163 if (!strcmp(mod->dump_file, filename) && 164 !strcmp(mod->name, modname)) 165 return mod; 166 } 167 return NULL; 168 } 169 170 static struct module *new_module(const char *name, size_t namelen) 171 { 172 struct module *mod; 173 174 mod = xmalloc(sizeof(*mod) + namelen + 1); 175 memset(mod, 0, sizeof(*mod)); 176 177 INIT_LIST_HEAD(&mod->exported_symbols); 178 INIT_LIST_HEAD(&mod->unresolved_symbols); 179 INIT_LIST_HEAD(&mod->missing_namespaces); 180 INIT_LIST_HEAD(&mod->imported_namespaces); 181 INIT_LIST_HEAD(&mod->aliases); 182 183 memcpy(mod->name, name, namelen); 184 mod->name[namelen] = '\0'; 185 mod->is_vmlinux = (strcmp(mod->name, "vmlinux") == 0); 186 187 /* 188 * Set mod->is_gpl_compatible to true by default. If MODULE_LICENSE() 189 * is missing, do not check the use for EXPORT_SYMBOL_GPL() becasue 190 * modpost will exit wiht error anyway. 191 */ 192 mod->is_gpl_compatible = true; 193 194 list_add_tail(&mod->list, &modules); 195 196 return mod; 197 } 198 199 struct symbol { 200 struct hlist_node hnode;/* link to hash table */ 201 struct list_head list; /* link to module::exported_symbols or module::unresolved_symbols */ 202 struct module *module; 203 char *namespace; 204 unsigned int crc; 205 bool crc_valid; 206 bool weak; 207 bool is_func; 208 bool is_gpl_only; /* exported by EXPORT_SYMBOL_GPL */ 209 bool used; /* there exists a user of this symbol */ 210 char name[]; 211 }; 212 213 static HASHTABLE_DEFINE(symbol_hashtable, 1U << 10); 214 215 /** 216 * Allocate a new symbols for use in the hash of exported symbols or 217 * the list of unresolved symbols per module 218 **/ 219 static struct symbol *alloc_symbol(const char *name) 220 { 221 struct symbol *s = xmalloc(sizeof(*s) + strlen(name) + 1); 222 223 memset(s, 0, sizeof(*s)); 224 strcpy(s->name, name); 225 226 return s; 227 } 228 229 /* For the hash of exported symbols */ 230 static void hash_add_symbol(struct symbol *sym) 231 { 232 hash_add(symbol_hashtable, &sym->hnode, hash_str(sym->name)); 233 } 234 235 static void sym_add_unresolved(const char *name, struct module *mod, bool weak) 236 { 237 struct symbol *sym; 238 239 sym = alloc_symbol(name); 240 sym->weak = weak; 241 242 list_add_tail(&sym->list, &mod->unresolved_symbols); 243 } 244 245 static struct symbol *sym_find_with_module(const char *name, struct module *mod) 246 { 247 struct symbol *s; 248 249 /* For our purposes, .foo matches foo. PPC64 needs this. */ 250 if (name[0] == '.') 251 name++; 252 253 hash_for_each_possible(symbol_hashtable, s, hnode, hash_str(name)) { 254 if (strcmp(s->name, name) == 0 && (!mod || s->module == mod)) 255 return s; 256 } 257 return NULL; 258 } 259 260 static struct symbol *find_symbol(const char *name) 261 { 262 return sym_find_with_module(name, NULL); 263 } 264 265 struct namespace_list { 266 struct list_head list; 267 char namespace[]; 268 }; 269 270 static bool contains_namespace(struct list_head *head, const char *namespace) 271 { 272 struct namespace_list *list; 273 274 /* 275 * The default namespace is null string "", which is always implicitly 276 * contained. 277 */ 278 if (!namespace[0]) 279 return true; 280 281 list_for_each_entry(list, head, list) { 282 if (!strcmp(list->namespace, namespace)) 283 return true; 284 } 285 286 return false; 287 } 288 289 static void add_namespace(struct list_head *head, const char *namespace) 290 { 291 struct namespace_list *ns_entry; 292 293 if (!contains_namespace(head, namespace)) { 294 ns_entry = xmalloc(sizeof(*ns_entry) + strlen(namespace) + 1); 295 strcpy(ns_entry->namespace, namespace); 296 list_add_tail(&ns_entry->list, head); 297 } 298 } 299 300 static void *sym_get_data_by_offset(const struct elf_info *info, 301 unsigned int secindex, unsigned long offset) 302 { 303 Elf_Shdr *sechdr = &info->sechdrs[secindex]; 304 305 return (void *)info->hdr + sechdr->sh_offset + offset; 306 } 307 308 void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym) 309 { 310 return sym_get_data_by_offset(info, get_secindex(info, sym), 311 sym->st_value); 312 } 313 314 static const char *sech_name(const struct elf_info *info, Elf_Shdr *sechdr) 315 { 316 return sym_get_data_by_offset(info, info->secindex_strings, 317 sechdr->sh_name); 318 } 319 320 static const char *sec_name(const struct elf_info *info, unsigned int secindex) 321 { 322 /* 323 * If sym->st_shndx is a special section index, there is no 324 * corresponding section header. 325 * Return "" if the index is out of range of info->sechdrs[] array. 326 */ 327 if (secindex >= info->num_sections) 328 return ""; 329 330 return sech_name(info, &info->sechdrs[secindex]); 331 } 332 333 static struct symbol *sym_add_exported(const char *name, struct module *mod, 334 bool gpl_only, const char *namespace) 335 { 336 struct symbol *s = find_symbol(name); 337 338 if (s && (!external_module || s->module->is_vmlinux || s->module == mod)) { 339 error("%s: '%s' exported twice. Previous export was in %s%s\n", 340 mod->name, name, s->module->name, 341 s->module->is_vmlinux ? "" : ".ko"); 342 } 343 344 s = alloc_symbol(name); 345 s->module = mod; 346 s->is_gpl_only = gpl_only; 347 s->namespace = xstrdup(namespace); 348 list_add_tail(&s->list, &mod->exported_symbols); 349 hash_add_symbol(s); 350 351 return s; 352 } 353 354 static void sym_set_crc(struct symbol *sym, unsigned int crc) 355 { 356 sym->crc = crc; 357 sym->crc_valid = true; 358 } 359 360 static void *grab_file(const char *filename, size_t *size) 361 { 362 struct stat st; 363 void *map = MAP_FAILED; 364 int fd; 365 366 fd = open(filename, O_RDONLY); 367 if (fd < 0) 368 return NULL; 369 if (fstat(fd, &st)) 370 goto failed; 371 372 *size = st.st_size; 373 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); 374 375 failed: 376 close(fd); 377 if (map == MAP_FAILED) 378 return NULL; 379 return map; 380 } 381 382 static void release_file(void *file, size_t size) 383 { 384 munmap(file, size); 385 } 386 387 static int parse_elf(struct elf_info *info, const char *filename) 388 { 389 unsigned int i; 390 Elf_Ehdr *hdr; 391 Elf_Shdr *sechdrs; 392 Elf_Sym *sym; 393 const char *secstrings; 394 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U; 395 396 hdr = grab_file(filename, &info->size); 397 if (!hdr) { 398 if (ignore_missing_files) { 399 fprintf(stderr, "%s: %s (ignored)\n", filename, 400 strerror(errno)); 401 return 0; 402 } 403 perror(filename); 404 exit(1); 405 } 406 info->hdr = hdr; 407 if (info->size < sizeof(*hdr)) { 408 /* file too small, assume this is an empty .o file */ 409 return 0; 410 } 411 /* Is this a valid ELF file? */ 412 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) || 413 (hdr->e_ident[EI_MAG1] != ELFMAG1) || 414 (hdr->e_ident[EI_MAG2] != ELFMAG2) || 415 (hdr->e_ident[EI_MAG3] != ELFMAG3)) { 416 /* Not an ELF file - silently ignore it */ 417 return 0; 418 } 419 420 switch (hdr->e_ident[EI_DATA]) { 421 case ELFDATA2LSB: 422 target_is_big_endian = false; 423 break; 424 case ELFDATA2MSB: 425 target_is_big_endian = true; 426 break; 427 default: 428 fatal("target endian is unknown\n"); 429 } 430 431 /* Fix endianness in ELF header */ 432 hdr->e_type = TO_NATIVE(hdr->e_type); 433 hdr->e_machine = TO_NATIVE(hdr->e_machine); 434 hdr->e_version = TO_NATIVE(hdr->e_version); 435 hdr->e_entry = TO_NATIVE(hdr->e_entry); 436 hdr->e_phoff = TO_NATIVE(hdr->e_phoff); 437 hdr->e_shoff = TO_NATIVE(hdr->e_shoff); 438 hdr->e_flags = TO_NATIVE(hdr->e_flags); 439 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize); 440 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize); 441 hdr->e_phnum = TO_NATIVE(hdr->e_phnum); 442 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize); 443 hdr->e_shnum = TO_NATIVE(hdr->e_shnum); 444 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx); 445 sechdrs = (void *)hdr + hdr->e_shoff; 446 info->sechdrs = sechdrs; 447 448 /* modpost only works for relocatable objects */ 449 if (hdr->e_type != ET_REL) 450 fatal("%s: not relocatable object.", filename); 451 452 /* Check if file offset is correct */ 453 if (hdr->e_shoff > info->size) 454 fatal("section header offset=%lu in file '%s' is bigger than filesize=%zu\n", 455 (unsigned long)hdr->e_shoff, filename, info->size); 456 457 if (hdr->e_shnum == SHN_UNDEF) { 458 /* 459 * There are more than 64k sections, 460 * read count from .sh_size. 461 */ 462 info->num_sections = TO_NATIVE(sechdrs[0].sh_size); 463 } 464 else { 465 info->num_sections = hdr->e_shnum; 466 } 467 if (hdr->e_shstrndx == SHN_XINDEX) { 468 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link); 469 } 470 else { 471 info->secindex_strings = hdr->e_shstrndx; 472 } 473 474 /* Fix endianness in section headers */ 475 for (i = 0; i < info->num_sections; i++) { 476 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name); 477 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); 478 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags); 479 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr); 480 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset); 481 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size); 482 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link); 483 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info); 484 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign); 485 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize); 486 } 487 /* Find symbol table. */ 488 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset; 489 for (i = 1; i < info->num_sections; i++) { 490 const char *secname; 491 int nobits = sechdrs[i].sh_type == SHT_NOBITS; 492 493 if (!nobits && sechdrs[i].sh_offset > info->size) 494 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > sizeof(*hrd)=%zu\n", 495 filename, (unsigned long)sechdrs[i].sh_offset, 496 sizeof(*hdr)); 497 498 secname = secstrings + sechdrs[i].sh_name; 499 if (strcmp(secname, ".modinfo") == 0) { 500 if (nobits) 501 fatal("%s has NOBITS .modinfo\n", filename); 502 info->modinfo = (void *)hdr + sechdrs[i].sh_offset; 503 info->modinfo_len = sechdrs[i].sh_size; 504 } else if (!strcmp(secname, ".export_symbol")) { 505 info->export_symbol_secndx = i; 506 } 507 508 if (sechdrs[i].sh_type == SHT_SYMTAB) { 509 unsigned int sh_link_idx; 510 symtab_idx = i; 511 info->symtab_start = (void *)hdr + 512 sechdrs[i].sh_offset; 513 info->symtab_stop = (void *)hdr + 514 sechdrs[i].sh_offset + sechdrs[i].sh_size; 515 sh_link_idx = sechdrs[i].sh_link; 516 info->strtab = (void *)hdr + 517 sechdrs[sh_link_idx].sh_offset; 518 } 519 520 /* 32bit section no. table? ("more than 64k sections") */ 521 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) { 522 symtab_shndx_idx = i; 523 info->symtab_shndx_start = (void *)hdr + 524 sechdrs[i].sh_offset; 525 info->symtab_shndx_stop = (void *)hdr + 526 sechdrs[i].sh_offset + sechdrs[i].sh_size; 527 } 528 } 529 if (!info->symtab_start) 530 fatal("%s has no symtab?\n", filename); 531 532 /* Fix endianness in symbols */ 533 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) { 534 sym->st_shndx = TO_NATIVE(sym->st_shndx); 535 sym->st_name = TO_NATIVE(sym->st_name); 536 sym->st_value = TO_NATIVE(sym->st_value); 537 sym->st_size = TO_NATIVE(sym->st_size); 538 } 539 540 if (symtab_shndx_idx != ~0U) { 541 Elf32_Word *p; 542 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link) 543 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n", 544 filename, sechdrs[symtab_shndx_idx].sh_link, 545 symtab_idx); 546 /* Fix endianness */ 547 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop; 548 p++) 549 *p = TO_NATIVE(*p); 550 } 551 552 symsearch_init(info); 553 554 return 1; 555 } 556 557 static void parse_elf_finish(struct elf_info *info) 558 { 559 symsearch_finish(info); 560 release_file(info->hdr, info->size); 561 } 562 563 static int ignore_undef_symbol(struct elf_info *info, const char *symname) 564 { 565 /* ignore __this_module, it will be resolved shortly */ 566 if (strcmp(symname, "__this_module") == 0) 567 return 1; 568 /* ignore global offset table */ 569 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0) 570 return 1; 571 if (info->hdr->e_machine == EM_PPC) 572 /* Special register function linked on all modules during final link of .ko */ 573 if (strstarts(symname, "_restgpr_") || 574 strstarts(symname, "_savegpr_") || 575 strstarts(symname, "_rest32gpr_") || 576 strstarts(symname, "_save32gpr_") || 577 strstarts(symname, "_restvr_") || 578 strstarts(symname, "_savevr_")) 579 return 1; 580 if (info->hdr->e_machine == EM_PPC64) 581 /* Special register function linked on all modules during final link of .ko */ 582 if (strstarts(symname, "_restgpr0_") || 583 strstarts(symname, "_savegpr0_") || 584 strstarts(symname, "_restvr_") || 585 strstarts(symname, "_savevr_") || 586 strcmp(symname, ".TOC.") == 0) 587 return 1; 588 /* Do not ignore this symbol */ 589 return 0; 590 } 591 592 static void handle_symbol(struct module *mod, struct elf_info *info, 593 const Elf_Sym *sym, const char *symname) 594 { 595 switch (sym->st_shndx) { 596 case SHN_COMMON: 597 if (strstarts(symname, "__gnu_lto_")) { 598 /* Should warn here, but modpost runs before the linker */ 599 } else 600 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name); 601 break; 602 case SHN_UNDEF: 603 /* undefined symbol */ 604 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 605 ELF_ST_BIND(sym->st_info) != STB_WEAK) 606 break; 607 if (ignore_undef_symbol(info, symname)) 608 break; 609 if (info->hdr->e_machine == EM_SPARC || 610 info->hdr->e_machine == EM_SPARCV9) { 611 /* Ignore register directives. */ 612 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER) 613 break; 614 if (symname[0] == '.') { 615 char *munged = xstrdup(symname); 616 munged[0] = '_'; 617 munged[1] = toupper(munged[1]); 618 symname = munged; 619 } 620 } 621 622 sym_add_unresolved(symname, mod, 623 ELF_ST_BIND(sym->st_info) == STB_WEAK); 624 break; 625 default: 626 if (strcmp(symname, "init_module") == 0) 627 mod->has_init = true; 628 if (strcmp(symname, "cleanup_module") == 0) 629 mod->has_cleanup = true; 630 break; 631 } 632 } 633 634 /** 635 * Parse tag=value strings from .modinfo section 636 **/ 637 static char *next_string(char *string, unsigned long *secsize) 638 { 639 /* Skip non-zero chars */ 640 while (string[0]) { 641 string++; 642 if ((*secsize)-- <= 1) 643 return NULL; 644 } 645 646 /* Skip any zero padding. */ 647 while (!string[0]) { 648 string++; 649 if ((*secsize)-- <= 1) 650 return NULL; 651 } 652 return string; 653 } 654 655 static char *get_next_modinfo(struct elf_info *info, const char *tag, 656 char *prev) 657 { 658 char *p; 659 unsigned int taglen = strlen(tag); 660 char *modinfo = info->modinfo; 661 unsigned long size = info->modinfo_len; 662 663 if (prev) { 664 size -= prev - modinfo; 665 modinfo = next_string(prev, &size); 666 } 667 668 for (p = modinfo; p; p = next_string(p, &size)) { 669 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') 670 return p + taglen + 1; 671 } 672 return NULL; 673 } 674 675 static char *get_modinfo(struct elf_info *info, const char *tag) 676 677 { 678 return get_next_modinfo(info, tag, NULL); 679 } 680 681 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) 682 { 683 return sym ? elf->strtab + sym->st_name : ""; 684 } 685 686 /* 687 * Check whether the 'string' argument matches one of the 'patterns', 688 * an array of shell wildcard patterns (glob). 689 * 690 * Return true is there is a match. 691 */ 692 static bool match(const char *string, const char *const patterns[]) 693 { 694 const char *pattern; 695 696 while ((pattern = *patterns++)) { 697 if (!fnmatch(pattern, string, 0)) 698 return true; 699 } 700 701 return false; 702 } 703 704 /* useful to pass patterns to match() directly */ 705 #define PATTERNS(...) \ 706 ({ \ 707 static const char *const patterns[] = {__VA_ARGS__, NULL}; \ 708 patterns; \ 709 }) 710 711 /* sections that we do not want to do full section mismatch check on */ 712 static const char *const section_white_list[] = 713 { 714 ".comment*", 715 ".debug*", 716 ".zdebug*", /* Compressed debug sections. */ 717 ".GCC.command.line", /* record-gcc-switches */ 718 ".mdebug*", /* alpha, score, mips etc. */ 719 ".pdr", /* alpha, score, mips etc. */ 720 ".stab*", 721 ".note*", 722 ".got*", 723 ".toc*", 724 ".xt.prop", /* xtensa */ 725 ".xt.lit", /* xtensa */ 726 ".arcextmap*", /* arc */ 727 ".gnu.linkonce.arcext*", /* arc : modules */ 728 ".cmem*", /* EZchip */ 729 ".fmt_slot*", /* EZchip */ 730 ".gnu.lto*", 731 ".discard.*", 732 ".llvm.call-graph-profile", /* call graph */ 733 NULL 734 }; 735 736 /* 737 * This is used to find sections missing the SHF_ALLOC flag. 738 * The cause of this is often a section specified in assembler 739 * without "ax" / "aw". 740 */ 741 static void check_section(const char *modname, struct elf_info *elf, 742 Elf_Shdr *sechdr) 743 { 744 const char *sec = sech_name(elf, sechdr); 745 746 if (sechdr->sh_type == SHT_PROGBITS && 747 !(sechdr->sh_flags & SHF_ALLOC) && 748 !match(sec, section_white_list)) { 749 warn("%s (%s): unexpected non-allocatable section.\n" 750 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n" 751 "Note that for example <linux/init.h> contains\n" 752 "section definitions for use in .S files.\n\n", 753 modname, sec); 754 } 755 } 756 757 758 759 #define ALL_INIT_DATA_SECTIONS \ 760 ".init.setup", ".init.rodata", ".init.data" 761 762 #define ALL_PCI_INIT_SECTIONS \ 763 ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \ 764 ".pci_fixup_enable", ".pci_fixup_resume", \ 765 ".pci_fixup_resume_early", ".pci_fixup_suspend" 766 767 #define ALL_INIT_SECTIONS ".init.*" 768 #define ALL_EXIT_SECTIONS ".exit.*" 769 770 #define DATA_SECTIONS ".data", ".data.rel" 771 #define TEXT_SECTIONS ".text", ".text.*", ".sched.text", \ 772 ".kprobes.text", ".cpuidle.text", ".noinstr.text", \ 773 ".ltext", ".ltext.*" 774 #define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \ 775 ".fixup", ".entry.text", ".exception.text", \ 776 ".coldtext", ".softirqentry.text", ".irqentry.text" 777 778 #define ALL_TEXT_SECTIONS ".init.text", ".exit.text", \ 779 TEXT_SECTIONS, OTHER_TEXT_SECTIONS 780 781 enum mismatch { 782 TEXTDATA_TO_ANY_INIT_EXIT, 783 XXXINIT_TO_SOME_INIT, 784 ANY_INIT_TO_ANY_EXIT, 785 ANY_EXIT_TO_ANY_INIT, 786 EXTABLE_TO_NON_TEXT, 787 }; 788 789 /** 790 * Describe how to match sections on different criteria: 791 * 792 * @fromsec: Array of sections to be matched. 793 * 794 * @bad_tosec: Relocations applied to a section in @fromsec to a section in 795 * this array is forbidden (black-list). Can be empty. 796 * 797 * @good_tosec: Relocations applied to a section in @fromsec must be 798 * targeting sections in this array (white-list). Can be empty. 799 * 800 * @mismatch: Type of mismatch. 801 */ 802 struct sectioncheck { 803 const char *fromsec[20]; 804 const char *bad_tosec[20]; 805 const char *good_tosec[20]; 806 enum mismatch mismatch; 807 }; 808 809 static const struct sectioncheck sectioncheck[] = { 810 /* Do not reference init/exit code/data from 811 * normal code and data 812 */ 813 { 814 .fromsec = { TEXT_SECTIONS, DATA_SECTIONS, NULL }, 815 .bad_tosec = { ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }, 816 .mismatch = TEXTDATA_TO_ANY_INIT_EXIT, 817 }, 818 /* Do not use exit code/data from init code */ 819 { 820 .fromsec = { ALL_INIT_SECTIONS, NULL }, 821 .bad_tosec = { ALL_EXIT_SECTIONS, NULL }, 822 .mismatch = ANY_INIT_TO_ANY_EXIT, 823 }, 824 /* Do not use init code/data from exit code */ 825 { 826 .fromsec = { ALL_EXIT_SECTIONS, NULL }, 827 .bad_tosec = { ALL_INIT_SECTIONS, NULL }, 828 .mismatch = ANY_EXIT_TO_ANY_INIT, 829 }, 830 { 831 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL }, 832 .bad_tosec = { ALL_INIT_SECTIONS, NULL }, 833 .mismatch = ANY_INIT_TO_ANY_EXIT, 834 }, 835 { 836 .fromsec = { "__ex_table", NULL }, 837 /* If you're adding any new black-listed sections in here, consider 838 * adding a special 'printer' for them in scripts/check_extable. 839 */ 840 .bad_tosec = { ".altinstr_replacement", NULL }, 841 .good_tosec = {ALL_TEXT_SECTIONS , NULL}, 842 .mismatch = EXTABLE_TO_NON_TEXT, 843 } 844 }; 845 846 static const struct sectioncheck *section_mismatch( 847 const char *fromsec, const char *tosec) 848 { 849 int i; 850 851 /* 852 * The target section could be the SHT_NUL section when we're 853 * handling relocations to un-resolved symbols, trying to match it 854 * doesn't make much sense and causes build failures on parisc 855 * architectures. 856 */ 857 if (*tosec == '\0') 858 return NULL; 859 860 for (i = 0; i < ARRAY_SIZE(sectioncheck); i++) { 861 const struct sectioncheck *check = §ioncheck[i]; 862 863 if (match(fromsec, check->fromsec)) { 864 if (check->bad_tosec[0] && match(tosec, check->bad_tosec)) 865 return check; 866 if (check->good_tosec[0] && !match(tosec, check->good_tosec)) 867 return check; 868 } 869 } 870 return NULL; 871 } 872 873 /** 874 * Whitelist to allow certain references to pass with no warning. 875 * 876 * Pattern 1: 877 * If a module parameter is declared __initdata and permissions=0 878 * then this is legal despite the warning generated. 879 * We cannot see value of permissions here, so just ignore 880 * this pattern. 881 * The pattern is identified by: 882 * tosec = .init.data 883 * fromsec = .data* 884 * atsym =__param* 885 * 886 * Pattern 1a: 887 * module_param_call() ops can refer to __init set function if permissions=0 888 * The pattern is identified by: 889 * tosec = .init.text 890 * fromsec = .data* 891 * atsym = __param_ops_* 892 * 893 * Pattern 3: 894 * Whitelist all references from .head.text to any init section 895 * 896 * Pattern 4: 897 * Some symbols belong to init section but still it is ok to reference 898 * these from non-init sections as these symbols don't have any memory 899 * allocated for them and symbol address and value are same. So even 900 * if init section is freed, its ok to reference those symbols. 901 * For ex. symbols marking the init section boundaries. 902 * This pattern is identified by 903 * refsymname = __init_begin, _sinittext, _einittext 904 * 905 * Pattern 5: 906 * GCC may optimize static inlines when fed constant arg(s) resulting 907 * in functions like cpumask_empty() -- generating an associated symbol 908 * cpumask_empty.constprop.3 that appears in the audit. If the const that 909 * is passed in comes from __init, like say nmi_ipi_mask, we get a 910 * meaningless section warning. May need to add isra symbols too... 911 * This pattern is identified by 912 * tosec = init section 913 * fromsec = text section 914 * refsymname = *.constprop.* 915 * 916 **/ 917 static int secref_whitelist(const char *fromsec, const char *fromsym, 918 const char *tosec, const char *tosym) 919 { 920 /* Check for pattern 1 */ 921 if (match(tosec, PATTERNS(ALL_INIT_DATA_SECTIONS)) && 922 match(fromsec, PATTERNS(DATA_SECTIONS)) && 923 strstarts(fromsym, "__param")) 924 return 0; 925 926 /* Check for pattern 1a */ 927 if (strcmp(tosec, ".init.text") == 0 && 928 match(fromsec, PATTERNS(DATA_SECTIONS)) && 929 strstarts(fromsym, "__param_ops_")) 930 return 0; 931 932 /* symbols in data sections that may refer to any init/exit sections */ 933 if (match(fromsec, PATTERNS(DATA_SECTIONS)) && 934 match(tosec, PATTERNS(ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS)) && 935 match(fromsym, PATTERNS("*_ops", "*_probe", "*_console"))) 936 return 0; 937 938 /* Check for pattern 3 */ 939 if (strstarts(fromsec, ".head.text") && 940 match(tosec, PATTERNS(ALL_INIT_SECTIONS))) 941 return 0; 942 943 /* Check for pattern 4 */ 944 if (match(tosym, PATTERNS("__init_begin", "_sinittext", "_einittext"))) 945 return 0; 946 947 /* Check for pattern 5 */ 948 if (match(fromsec, PATTERNS(ALL_TEXT_SECTIONS)) && 949 match(tosec, PATTERNS(ALL_INIT_SECTIONS)) && 950 match(fromsym, PATTERNS("*.constprop.*"))) 951 return 0; 952 953 return 1; 954 } 955 956 static Elf_Sym *find_fromsym(struct elf_info *elf, Elf_Addr addr, 957 unsigned int secndx) 958 { 959 return symsearch_find_nearest(elf, addr, secndx, false, ~0); 960 } 961 962 static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym) 963 { 964 Elf_Sym *new_sym; 965 966 /* If the supplied symbol has a valid name, return it */ 967 if (is_valid_name(elf, sym)) 968 return sym; 969 970 /* 971 * Strive to find a better symbol name, but the resulting name may not 972 * match the symbol referenced in the original code. 973 */ 974 new_sym = symsearch_find_nearest(elf, addr, get_secindex(elf, sym), 975 true, 20); 976 return new_sym ? new_sym : sym; 977 } 978 979 static bool is_executable_section(struct elf_info *elf, unsigned int secndx) 980 { 981 if (secndx >= elf->num_sections) 982 return false; 983 984 return (elf->sechdrs[secndx].sh_flags & SHF_EXECINSTR) != 0; 985 } 986 987 static void default_mismatch_handler(const char *modname, struct elf_info *elf, 988 const struct sectioncheck* const mismatch, 989 Elf_Sym *tsym, 990 unsigned int fsecndx, const char *fromsec, Elf_Addr faddr, 991 const char *tosec, Elf_Addr taddr) 992 { 993 Elf_Sym *from; 994 const char *tosym; 995 const char *fromsym; 996 char taddr_str[16]; 997 998 from = find_fromsym(elf, faddr, fsecndx); 999 fromsym = sym_name(elf, from); 1000 1001 tsym = find_tosym(elf, taddr, tsym); 1002 tosym = sym_name(elf, tsym); 1003 1004 /* check whitelist - we may ignore it */ 1005 if (!secref_whitelist(fromsec, fromsym, tosec, tosym)) 1006 return; 1007 1008 sec_mismatch_count++; 1009 1010 if (!tosym[0]) 1011 snprintf(taddr_str, sizeof(taddr_str), "0x%x", (unsigned int)taddr); 1012 1013 /* 1014 * The format for the reference source: <symbol_name>+<offset> or <address> 1015 * The format for the reference destination: <symbol_name> or <address> 1016 */ 1017 warn("%s: section mismatch in reference: %s%s0x%x (section: %s) -> %s (section: %s)\n", 1018 modname, fromsym, fromsym[0] ? "+" : "", 1019 (unsigned int)(faddr - (fromsym[0] ? from->st_value : 0)), 1020 fromsec, tosym[0] ? tosym : taddr_str, tosec); 1021 1022 if (mismatch->mismatch == EXTABLE_TO_NON_TEXT) { 1023 if (match(tosec, mismatch->bad_tosec)) 1024 fatal("The relocation at %s+0x%lx references\n" 1025 "section \"%s\" which is black-listed.\n" 1026 "Something is seriously wrong and should be fixed.\n" 1027 "You might get more information about where this is\n" 1028 "coming from by using scripts/check_extable.sh %s\n", 1029 fromsec, (long)faddr, tosec, modname); 1030 else if (is_executable_section(elf, get_secindex(elf, tsym))) 1031 warn("The relocation at %s+0x%lx references\n" 1032 "section \"%s\" which is not in the list of\n" 1033 "authorized sections. If you're adding a new section\n" 1034 "and/or if this reference is valid, add \"%s\" to the\n" 1035 "list of authorized sections to jump to on fault.\n" 1036 "This can be achieved by adding \"%s\" to\n" 1037 "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n", 1038 fromsec, (long)faddr, tosec, tosec, tosec); 1039 else 1040 error("%s+0x%lx references non-executable section '%s'\n", 1041 fromsec, (long)faddr, tosec); 1042 } 1043 } 1044 1045 static void check_export_symbol(struct module *mod, struct elf_info *elf, 1046 Elf_Addr faddr, const char *secname, 1047 Elf_Sym *sym) 1048 { 1049 static const char *prefix = "__export_symbol_"; 1050 const char *label_name, *name, *data; 1051 Elf_Sym *label; 1052 struct symbol *s; 1053 bool is_gpl; 1054 1055 label = find_fromsym(elf, faddr, elf->export_symbol_secndx); 1056 label_name = sym_name(elf, label); 1057 1058 if (!strstarts(label_name, prefix)) { 1059 error("%s: .export_symbol section contains strange symbol '%s'\n", 1060 mod->name, label_name); 1061 return; 1062 } 1063 1064 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 1065 ELF_ST_BIND(sym->st_info) != STB_WEAK) { 1066 error("%s: local symbol '%s' was exported\n", mod->name, 1067 label_name + strlen(prefix)); 1068 return; 1069 } 1070 1071 name = sym_name(elf, sym); 1072 if (strcmp(label_name + strlen(prefix), name)) { 1073 error("%s: .export_symbol section references '%s', but it does not seem to be an export symbol\n", 1074 mod->name, name); 1075 return; 1076 } 1077 1078 data = sym_get_data(elf, label); /* license */ 1079 if (!strcmp(data, "GPL")) { 1080 is_gpl = true; 1081 } else if (!strcmp(data, "")) { 1082 is_gpl = false; 1083 } else { 1084 error("%s: unknown license '%s' was specified for '%s'\n", 1085 mod->name, data, name); 1086 return; 1087 } 1088 1089 data += strlen(data) + 1; /* namespace */ 1090 s = sym_add_exported(name, mod, is_gpl, data); 1091 1092 /* 1093 * We need to be aware whether we are exporting a function or 1094 * a data on some architectures. 1095 */ 1096 s->is_func = (ELF_ST_TYPE(sym->st_info) == STT_FUNC); 1097 1098 /* 1099 * For parisc64, symbols prefixed $$ from the library have the symbol type 1100 * STT_LOPROC. They should be handled as functions too. 1101 */ 1102 if (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64 && 1103 elf->hdr->e_machine == EM_PARISC && 1104 ELF_ST_TYPE(sym->st_info) == STT_LOPROC) 1105 s->is_func = true; 1106 1107 if (match(secname, PATTERNS(ALL_INIT_SECTIONS))) 1108 warn("%s: %s: EXPORT_SYMBOL used for init symbol. Remove __init or EXPORT_SYMBOL.\n", 1109 mod->name, name); 1110 else if (match(secname, PATTERNS(ALL_EXIT_SECTIONS))) 1111 warn("%s: %s: EXPORT_SYMBOL used for exit symbol. Remove __exit or EXPORT_SYMBOL.\n", 1112 mod->name, name); 1113 } 1114 1115 static void check_section_mismatch(struct module *mod, struct elf_info *elf, 1116 Elf_Sym *sym, 1117 unsigned int fsecndx, const char *fromsec, 1118 Elf_Addr faddr, Elf_Addr taddr) 1119 { 1120 const char *tosec = sec_name(elf, get_secindex(elf, sym)); 1121 const struct sectioncheck *mismatch; 1122 1123 if (module_enabled && elf->export_symbol_secndx == fsecndx) { 1124 check_export_symbol(mod, elf, faddr, tosec, sym); 1125 return; 1126 } 1127 1128 mismatch = section_mismatch(fromsec, tosec); 1129 if (!mismatch) 1130 return; 1131 1132 default_mismatch_handler(mod->name, elf, mismatch, sym, 1133 fsecndx, fromsec, faddr, 1134 tosec, taddr); 1135 } 1136 1137 static Elf_Addr addend_386_rel(uint32_t *location, unsigned int r_type) 1138 { 1139 switch (r_type) { 1140 case R_386_32: 1141 return get_unaligned_native(location); 1142 case R_386_PC32: 1143 return get_unaligned_native(location) + 4; 1144 } 1145 1146 return (Elf_Addr)(-1); 1147 } 1148 1149 static int32_t sign_extend32(int32_t value, int index) 1150 { 1151 uint8_t shift = 31 - index; 1152 1153 return (int32_t)(value << shift) >> shift; 1154 } 1155 1156 static Elf_Addr addend_arm_rel(void *loc, Elf_Sym *sym, unsigned int r_type) 1157 { 1158 uint32_t inst, upper, lower, sign, j1, j2; 1159 int32_t offset; 1160 1161 switch (r_type) { 1162 case R_ARM_ABS32: 1163 case R_ARM_REL32: 1164 inst = get_unaligned_native((uint32_t *)loc); 1165 return inst + sym->st_value; 1166 case R_ARM_MOVW_ABS_NC: 1167 case R_ARM_MOVT_ABS: 1168 inst = get_unaligned_native((uint32_t *)loc); 1169 offset = sign_extend32(((inst & 0xf0000) >> 4) | (inst & 0xfff), 1170 15); 1171 return offset + sym->st_value; 1172 case R_ARM_PC24: 1173 case R_ARM_CALL: 1174 case R_ARM_JUMP24: 1175 inst = get_unaligned_native((uint32_t *)loc); 1176 offset = sign_extend32((inst & 0x00ffffff) << 2, 25); 1177 return offset + sym->st_value + 8; 1178 case R_ARM_THM_MOVW_ABS_NC: 1179 case R_ARM_THM_MOVT_ABS: 1180 upper = get_unaligned_native((uint16_t *)loc); 1181 lower = get_unaligned_native((uint16_t *)loc + 1); 1182 offset = sign_extend32(((upper & 0x000f) << 12) | 1183 ((upper & 0x0400) << 1) | 1184 ((lower & 0x7000) >> 4) | 1185 (lower & 0x00ff), 1186 15); 1187 return offset + sym->st_value; 1188 case R_ARM_THM_JUMP19: 1189 /* 1190 * Encoding T3: 1191 * S = upper[10] 1192 * imm6 = upper[5:0] 1193 * J1 = lower[13] 1194 * J2 = lower[11] 1195 * imm11 = lower[10:0] 1196 * imm32 = SignExtend(S:J2:J1:imm6:imm11:'0') 1197 */ 1198 upper = get_unaligned_native((uint16_t *)loc); 1199 lower = get_unaligned_native((uint16_t *)loc + 1); 1200 1201 sign = (upper >> 10) & 1; 1202 j1 = (lower >> 13) & 1; 1203 j2 = (lower >> 11) & 1; 1204 offset = sign_extend32((sign << 20) | (j2 << 19) | (j1 << 18) | 1205 ((upper & 0x03f) << 12) | 1206 ((lower & 0x07ff) << 1), 1207 20); 1208 return offset + sym->st_value + 4; 1209 case R_ARM_THM_PC22: 1210 case R_ARM_THM_JUMP24: 1211 /* 1212 * Encoding T4: 1213 * S = upper[10] 1214 * imm10 = upper[9:0] 1215 * J1 = lower[13] 1216 * J2 = lower[11] 1217 * imm11 = lower[10:0] 1218 * I1 = NOT(J1 XOR S) 1219 * I2 = NOT(J2 XOR S) 1220 * imm32 = SignExtend(S:I1:I2:imm10:imm11:'0') 1221 */ 1222 upper = get_unaligned_native((uint16_t *)loc); 1223 lower = get_unaligned_native((uint16_t *)loc + 1); 1224 1225 sign = (upper >> 10) & 1; 1226 j1 = (lower >> 13) & 1; 1227 j2 = (lower >> 11) & 1; 1228 offset = sign_extend32((sign << 24) | 1229 ((~(j1 ^ sign) & 1) << 23) | 1230 ((~(j2 ^ sign) & 1) << 22) | 1231 ((upper & 0x03ff) << 12) | 1232 ((lower & 0x07ff) << 1), 1233 24); 1234 return offset + sym->st_value + 4; 1235 } 1236 1237 return (Elf_Addr)(-1); 1238 } 1239 1240 static Elf_Addr addend_mips_rel(uint32_t *location, unsigned int r_type) 1241 { 1242 uint32_t inst; 1243 1244 inst = get_unaligned_native(location); 1245 switch (r_type) { 1246 case R_MIPS_LO16: 1247 return inst & 0xffff; 1248 case R_MIPS_26: 1249 return (inst & 0x03ffffff) << 2; 1250 case R_MIPS_32: 1251 return inst; 1252 } 1253 return (Elf_Addr)(-1); 1254 } 1255 1256 #ifndef EM_RISCV 1257 #define EM_RISCV 243 1258 #endif 1259 1260 #ifndef R_RISCV_SUB32 1261 #define R_RISCV_SUB32 39 1262 #endif 1263 1264 #ifndef EM_LOONGARCH 1265 #define EM_LOONGARCH 258 1266 #endif 1267 1268 #ifndef R_LARCH_SUB32 1269 #define R_LARCH_SUB32 55 1270 #endif 1271 1272 #ifndef R_LARCH_RELAX 1273 #define R_LARCH_RELAX 100 1274 #endif 1275 1276 #ifndef R_LARCH_ALIGN 1277 #define R_LARCH_ALIGN 102 1278 #endif 1279 1280 static void get_rel_type_and_sym(struct elf_info *elf, uint64_t r_info, 1281 unsigned int *r_type, unsigned int *r_sym) 1282 { 1283 typedef struct { 1284 Elf64_Word r_sym; /* Symbol index */ 1285 unsigned char r_ssym; /* Special symbol for 2nd relocation */ 1286 unsigned char r_type3; /* 3rd relocation type */ 1287 unsigned char r_type2; /* 2nd relocation type */ 1288 unsigned char r_type; /* 1st relocation type */ 1289 } Elf64_Mips_R_Info; 1290 1291 bool is_64bit = (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64); 1292 1293 if (elf->hdr->e_machine == EM_MIPS && is_64bit) { 1294 Elf64_Mips_R_Info *mips64_r_info = (void *)&r_info; 1295 1296 *r_type = mips64_r_info->r_type; 1297 *r_sym = TO_NATIVE(mips64_r_info->r_sym); 1298 return; 1299 } 1300 1301 if (is_64bit) 1302 r_info = TO_NATIVE((Elf64_Xword)r_info); 1303 else 1304 r_info = TO_NATIVE((Elf32_Word)r_info); 1305 1306 *r_type = ELF_R_TYPE(r_info); 1307 *r_sym = ELF_R_SYM(r_info); 1308 } 1309 1310 static void section_rela(struct module *mod, struct elf_info *elf, 1311 unsigned int fsecndx, const char *fromsec, 1312 const Elf_Rela *start, const Elf_Rela *stop) 1313 { 1314 const Elf_Rela *rela; 1315 1316 for (rela = start; rela < stop; rela++) { 1317 Elf_Sym *tsym; 1318 Elf_Addr taddr, r_offset; 1319 unsigned int r_type, r_sym; 1320 1321 r_offset = TO_NATIVE(rela->r_offset); 1322 get_rel_type_and_sym(elf, rela->r_info, &r_type, &r_sym); 1323 1324 tsym = elf->symtab_start + r_sym; 1325 taddr = tsym->st_value + TO_NATIVE(rela->r_addend); 1326 1327 switch (elf->hdr->e_machine) { 1328 case EM_RISCV: 1329 if (!strcmp("__ex_table", fromsec) && 1330 r_type == R_RISCV_SUB32) 1331 continue; 1332 break; 1333 case EM_LOONGARCH: 1334 switch (r_type) { 1335 case R_LARCH_SUB32: 1336 if (!strcmp("__ex_table", fromsec)) 1337 continue; 1338 break; 1339 case R_LARCH_RELAX: 1340 case R_LARCH_ALIGN: 1341 /* These relocs do not refer to symbols */ 1342 continue; 1343 } 1344 break; 1345 } 1346 1347 check_section_mismatch(mod, elf, tsym, 1348 fsecndx, fromsec, r_offset, taddr); 1349 } 1350 } 1351 1352 static void section_rel(struct module *mod, struct elf_info *elf, 1353 unsigned int fsecndx, const char *fromsec, 1354 const Elf_Rel *start, const Elf_Rel *stop) 1355 { 1356 const Elf_Rel *rel; 1357 1358 for (rel = start; rel < stop; rel++) { 1359 Elf_Sym *tsym; 1360 Elf_Addr taddr, r_offset; 1361 unsigned int r_type, r_sym; 1362 void *loc; 1363 1364 r_offset = TO_NATIVE(rel->r_offset); 1365 get_rel_type_and_sym(elf, rel->r_info, &r_type, &r_sym); 1366 1367 loc = sym_get_data_by_offset(elf, fsecndx, r_offset); 1368 tsym = elf->symtab_start + r_sym; 1369 1370 switch (elf->hdr->e_machine) { 1371 case EM_386: 1372 taddr = addend_386_rel(loc, r_type); 1373 break; 1374 case EM_ARM: 1375 taddr = addend_arm_rel(loc, tsym, r_type); 1376 break; 1377 case EM_MIPS: 1378 taddr = addend_mips_rel(loc, r_type); 1379 break; 1380 default: 1381 fatal("Please add code to calculate addend for this architecture\n"); 1382 } 1383 1384 check_section_mismatch(mod, elf, tsym, 1385 fsecndx, fromsec, r_offset, taddr); 1386 } 1387 } 1388 1389 /** 1390 * A module includes a number of sections that are discarded 1391 * either when loaded or when used as built-in. 1392 * For loaded modules all functions marked __init and all data 1393 * marked __initdata will be discarded when the module has been initialized. 1394 * Likewise for modules used built-in the sections marked __exit 1395 * are discarded because __exit marked function are supposed to be called 1396 * only when a module is unloaded which never happens for built-in modules. 1397 * The check_sec_ref() function traverses all relocation records 1398 * to find all references to a section that reference a section that will 1399 * be discarded and warns about it. 1400 **/ 1401 static void check_sec_ref(struct module *mod, struct elf_info *elf) 1402 { 1403 int i; 1404 1405 /* Walk through all sections */ 1406 for (i = 0; i < elf->num_sections; i++) { 1407 Elf_Shdr *sechdr = &elf->sechdrs[i]; 1408 1409 check_section(mod->name, elf, sechdr); 1410 /* We want to process only relocation sections and not .init */ 1411 if (sechdr->sh_type == SHT_REL || sechdr->sh_type == SHT_RELA) { 1412 /* section to which the relocation applies */ 1413 unsigned int secndx = sechdr->sh_info; 1414 const char *secname = sec_name(elf, secndx); 1415 const void *start, *stop; 1416 1417 /* If the section is known good, skip it */ 1418 if (match(secname, section_white_list)) 1419 continue; 1420 1421 start = sym_get_data_by_offset(elf, i, 0); 1422 stop = start + sechdr->sh_size; 1423 1424 if (sechdr->sh_type == SHT_RELA) 1425 section_rela(mod, elf, secndx, secname, 1426 start, stop); 1427 else 1428 section_rel(mod, elf, secndx, secname, 1429 start, stop); 1430 } 1431 } 1432 } 1433 1434 static char *remove_dot(char *s) 1435 { 1436 size_t n = strcspn(s, "."); 1437 1438 if (n && s[n]) { 1439 size_t m = strspn(s + n + 1, "0123456789"); 1440 if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0)) 1441 s[n] = 0; 1442 } 1443 return s; 1444 } 1445 1446 /* 1447 * The CRCs are recorded in .*.cmd files in the form of: 1448 * #SYMVER <name> <crc> 1449 */ 1450 static void extract_crcs_for_object(const char *object, struct module *mod) 1451 { 1452 char cmd_file[PATH_MAX]; 1453 char *buf, *p; 1454 const char *base; 1455 int dirlen, ret; 1456 1457 base = strrchr(object, '/'); 1458 if (base) { 1459 base++; 1460 dirlen = base - object; 1461 } else { 1462 dirlen = 0; 1463 base = object; 1464 } 1465 1466 ret = snprintf(cmd_file, sizeof(cmd_file), "%.*s.%s.cmd", 1467 dirlen, object, base); 1468 if (ret >= sizeof(cmd_file)) { 1469 error("%s: too long path was truncated\n", cmd_file); 1470 return; 1471 } 1472 1473 buf = read_text_file(cmd_file); 1474 p = buf; 1475 1476 while ((p = strstr(p, "\n#SYMVER "))) { 1477 char *name; 1478 size_t namelen; 1479 unsigned int crc; 1480 struct symbol *sym; 1481 1482 name = p + strlen("\n#SYMVER "); 1483 1484 p = strchr(name, ' '); 1485 if (!p) 1486 break; 1487 1488 namelen = p - name; 1489 p++; 1490 1491 if (!isdigit(*p)) 1492 continue; /* skip this line */ 1493 1494 crc = strtoul(p, &p, 0); 1495 if (*p != '\n') 1496 continue; /* skip this line */ 1497 1498 name[namelen] = '\0'; 1499 1500 /* 1501 * sym_find_with_module() may return NULL here. 1502 * It typically occurs when CONFIG_TRIM_UNUSED_KSYMS=y. 1503 * Since commit e1327a127703, genksyms calculates CRCs of all 1504 * symbols, including trimmed ones. Ignore orphan CRCs. 1505 */ 1506 sym = sym_find_with_module(name, mod); 1507 if (sym) 1508 sym_set_crc(sym, crc); 1509 } 1510 1511 free(buf); 1512 } 1513 1514 /* 1515 * The symbol versions (CRC) are recorded in the .*.cmd files. 1516 * Parse them to retrieve CRCs for the current module. 1517 */ 1518 static void mod_set_crcs(struct module *mod) 1519 { 1520 char objlist[PATH_MAX]; 1521 char *buf, *p, *obj; 1522 int ret; 1523 1524 if (mod->is_vmlinux) { 1525 strcpy(objlist, ".vmlinux.objs"); 1526 } else { 1527 /* objects for a module are listed in the *.mod file. */ 1528 ret = snprintf(objlist, sizeof(objlist), "%s.mod", mod->name); 1529 if (ret >= sizeof(objlist)) { 1530 error("%s: too long path was truncated\n", objlist); 1531 return; 1532 } 1533 } 1534 1535 buf = read_text_file(objlist); 1536 p = buf; 1537 1538 while ((obj = strsep(&p, "\n")) && obj[0]) 1539 extract_crcs_for_object(obj, mod); 1540 1541 free(buf); 1542 } 1543 1544 static void read_symbols(const char *modname) 1545 { 1546 const char *symname; 1547 char *version; 1548 char *license; 1549 char *namespace; 1550 struct module *mod; 1551 struct elf_info info = { }; 1552 Elf_Sym *sym; 1553 1554 if (!parse_elf(&info, modname)) 1555 return; 1556 1557 if (!strends(modname, ".o")) { 1558 error("%s: filename must be suffixed with .o\n", modname); 1559 return; 1560 } 1561 1562 /* strip trailing .o */ 1563 mod = new_module(modname, strlen(modname) - strlen(".o")); 1564 1565 if (!mod->is_vmlinux) { 1566 license = get_modinfo(&info, "license"); 1567 if (!license) 1568 error("missing MODULE_LICENSE() in %s\n", modname); 1569 while (license) { 1570 if (!license_is_gpl_compatible(license)) { 1571 mod->is_gpl_compatible = false; 1572 break; 1573 } 1574 license = get_next_modinfo(&info, "license", license); 1575 } 1576 1577 namespace = get_modinfo(&info, "import_ns"); 1578 while (namespace) { 1579 add_namespace(&mod->imported_namespaces, namespace); 1580 namespace = get_next_modinfo(&info, "import_ns", 1581 namespace); 1582 } 1583 1584 if (extra_warn && !get_modinfo(&info, "description")) 1585 warn("missing MODULE_DESCRIPTION() in %s\n", modname); 1586 } 1587 1588 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { 1589 symname = remove_dot(info.strtab + sym->st_name); 1590 1591 handle_symbol(mod, &info, sym, symname); 1592 handle_moddevtable(mod, &info, sym, symname); 1593 } 1594 1595 check_sec_ref(mod, &info); 1596 1597 if (!mod->is_vmlinux) { 1598 version = get_modinfo(&info, "version"); 1599 if (version || all_versions) 1600 get_src_version(mod->name, mod->srcversion, 1601 sizeof(mod->srcversion) - 1); 1602 } 1603 1604 parse_elf_finish(&info); 1605 1606 if (modversions) { 1607 /* 1608 * Our trick to get versioning for module struct etc. - it's 1609 * never passed as an argument to an exported function, so 1610 * the automatic versioning doesn't pick it up, but it's really 1611 * important anyhow. 1612 */ 1613 sym_add_unresolved("module_layout", mod, false); 1614 1615 mod_set_crcs(mod); 1616 } 1617 } 1618 1619 static void read_symbols_from_files(const char *filename) 1620 { 1621 FILE *in = stdin; 1622 char fname[PATH_MAX]; 1623 1624 in = fopen(filename, "r"); 1625 if (!in) 1626 fatal("Can't open filenames file %s: %m", filename); 1627 1628 while (fgets(fname, PATH_MAX, in) != NULL) { 1629 if (strends(fname, "\n")) 1630 fname[strlen(fname)-1] = '\0'; 1631 read_symbols(fname); 1632 } 1633 1634 fclose(in); 1635 } 1636 1637 #define SZ 500 1638 1639 /* We first write the generated file into memory using the 1640 * following helper, then compare to the file on disk and 1641 * only update the later if anything changed */ 1642 1643 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf, 1644 const char *fmt, ...) 1645 { 1646 char tmp[SZ]; 1647 int len; 1648 va_list ap; 1649 1650 va_start(ap, fmt); 1651 len = vsnprintf(tmp, SZ, fmt, ap); 1652 buf_write(buf, tmp, len); 1653 va_end(ap); 1654 } 1655 1656 void buf_write(struct buffer *buf, const char *s, int len) 1657 { 1658 if (buf->size - buf->pos < len) { 1659 buf->size += len + SZ; 1660 buf->p = xrealloc(buf->p, buf->size); 1661 } 1662 strncpy(buf->p + buf->pos, s, len); 1663 buf->pos += len; 1664 } 1665 1666 static void check_exports(struct module *mod) 1667 { 1668 struct symbol *s, *exp; 1669 1670 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1671 const char *basename; 1672 exp = find_symbol(s->name); 1673 if (!exp) { 1674 if (!s->weak && nr_unresolved++ < MAX_UNRESOLVED_REPORTS) 1675 modpost_log(!warn_unresolved, 1676 "\"%s\" [%s.ko] undefined!\n", 1677 s->name, mod->name); 1678 continue; 1679 } 1680 if (exp->module == mod) { 1681 error("\"%s\" [%s.ko] was exported without definition\n", 1682 s->name, mod->name); 1683 continue; 1684 } 1685 1686 exp->used = true; 1687 s->module = exp->module; 1688 s->crc_valid = exp->crc_valid; 1689 s->crc = exp->crc; 1690 1691 basename = strrchr(mod->name, '/'); 1692 if (basename) 1693 basename++; 1694 else 1695 basename = mod->name; 1696 1697 if (!contains_namespace(&mod->imported_namespaces, exp->namespace)) { 1698 modpost_log(!allow_missing_ns_imports, 1699 "module %s uses symbol %s from namespace %s, but does not import it.\n", 1700 basename, exp->name, exp->namespace); 1701 add_namespace(&mod->missing_namespaces, exp->namespace); 1702 } 1703 1704 if (!mod->is_gpl_compatible && exp->is_gpl_only) 1705 error("GPL-incompatible module %s.ko uses GPL-only symbol '%s'\n", 1706 basename, exp->name); 1707 } 1708 } 1709 1710 static void handle_white_list_exports(const char *white_list) 1711 { 1712 char *buf, *p, *name; 1713 1714 buf = read_text_file(white_list); 1715 p = buf; 1716 1717 while ((name = strsep(&p, "\n"))) { 1718 struct symbol *sym = find_symbol(name); 1719 1720 if (sym) 1721 sym->used = true; 1722 } 1723 1724 free(buf); 1725 } 1726 1727 static void check_modname_len(struct module *mod) 1728 { 1729 const char *mod_name; 1730 1731 mod_name = strrchr(mod->name, '/'); 1732 if (mod_name == NULL) 1733 mod_name = mod->name; 1734 else 1735 mod_name++; 1736 if (strlen(mod_name) >= MODULE_NAME_LEN) 1737 error("module name is too long [%s.ko]\n", mod->name); 1738 } 1739 1740 /** 1741 * Header for the generated file 1742 **/ 1743 static void add_header(struct buffer *b, struct module *mod) 1744 { 1745 buf_printf(b, "#include <linux/module.h>\n"); 1746 buf_printf(b, "#include <linux/export-internal.h>\n"); 1747 buf_printf(b, "#include <linux/compiler.h>\n"); 1748 buf_printf(b, "\n"); 1749 buf_printf(b, "MODULE_INFO(name, KBUILD_MODNAME);\n"); 1750 buf_printf(b, "\n"); 1751 buf_printf(b, "__visible struct module __this_module\n"); 1752 buf_printf(b, "__section(\".gnu.linkonce.this_module\") = {\n"); 1753 buf_printf(b, "\t.name = KBUILD_MODNAME,\n"); 1754 if (mod->has_init) 1755 buf_printf(b, "\t.init = init_module,\n"); 1756 if (mod->has_cleanup) 1757 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n" 1758 "\t.exit = cleanup_module,\n" 1759 "#endif\n"); 1760 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n"); 1761 buf_printf(b, "};\n"); 1762 1763 if (!external_module) 1764 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n"); 1765 1766 if (strstarts(mod->name, "drivers/staging")) 1767 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); 1768 1769 if (strstarts(mod->name, "tools/testing")) 1770 buf_printf(b, "\nMODULE_INFO(test, \"Y\");\n"); 1771 } 1772 1773 static void add_exported_symbols(struct buffer *buf, struct module *mod) 1774 { 1775 struct symbol *sym; 1776 1777 /* generate struct for exported symbols */ 1778 buf_printf(buf, "\n"); 1779 list_for_each_entry(sym, &mod->exported_symbols, list) { 1780 if (trim_unused_exports && !sym->used) 1781 continue; 1782 1783 buf_printf(buf, "KSYMTAB_%s(%s, \"%s\", \"%s\");\n", 1784 sym->is_func ? "FUNC" : "DATA", sym->name, 1785 sym->is_gpl_only ? "_gpl" : "", sym->namespace); 1786 } 1787 1788 if (!modversions) 1789 return; 1790 1791 /* record CRCs for exported symbols */ 1792 buf_printf(buf, "\n"); 1793 list_for_each_entry(sym, &mod->exported_symbols, list) { 1794 if (trim_unused_exports && !sym->used) 1795 continue; 1796 1797 if (!sym->crc_valid) 1798 warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n" 1799 "Is \"%s\" prototyped in <asm/asm-prototypes.h>?\n", 1800 sym->name, mod->name, mod->is_vmlinux ? "" : ".ko", 1801 sym->name); 1802 1803 buf_printf(buf, "SYMBOL_CRC(%s, 0x%08x, \"%s\");\n", 1804 sym->name, sym->crc, sym->is_gpl_only ? "_gpl" : ""); 1805 } 1806 } 1807 1808 /** 1809 * Record CRCs for unresolved symbols 1810 **/ 1811 static void add_versions(struct buffer *b, struct module *mod) 1812 { 1813 struct symbol *s; 1814 1815 if (!modversions) 1816 return; 1817 1818 buf_printf(b, "\n"); 1819 buf_printf(b, "static const struct modversion_info ____versions[]\n"); 1820 buf_printf(b, "__used __section(\"__versions\") = {\n"); 1821 1822 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1823 if (!s->module) 1824 continue; 1825 if (!s->crc_valid) { 1826 warn("\"%s\" [%s.ko] has no CRC!\n", 1827 s->name, mod->name); 1828 continue; 1829 } 1830 if (strlen(s->name) >= MODULE_NAME_LEN) { 1831 error("too long symbol \"%s\" [%s.ko]\n", 1832 s->name, mod->name); 1833 break; 1834 } 1835 buf_printf(b, "\t{ %#8x, \"%s\" },\n", 1836 s->crc, s->name); 1837 } 1838 1839 buf_printf(b, "};\n"); 1840 } 1841 1842 static void add_depends(struct buffer *b, struct module *mod) 1843 { 1844 struct symbol *s; 1845 int first = 1; 1846 1847 /* Clear ->seen flag of modules that own symbols needed by this. */ 1848 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1849 if (s->module) 1850 s->module->seen = s->module->is_vmlinux; 1851 } 1852 1853 buf_printf(b, "\n"); 1854 buf_printf(b, "MODULE_INFO(depends, \""); 1855 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1856 const char *p; 1857 if (!s->module) 1858 continue; 1859 1860 if (s->module->seen) 1861 continue; 1862 1863 s->module->seen = true; 1864 p = strrchr(s->module->name, '/'); 1865 if (p) 1866 p++; 1867 else 1868 p = s->module->name; 1869 buf_printf(b, "%s%s", first ? "" : ",", p); 1870 first = 0; 1871 } 1872 buf_printf(b, "\");\n"); 1873 } 1874 1875 static void add_srcversion(struct buffer *b, struct module *mod) 1876 { 1877 if (mod->srcversion[0]) { 1878 buf_printf(b, "\n"); 1879 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n", 1880 mod->srcversion); 1881 } 1882 } 1883 1884 static void write_buf(struct buffer *b, const char *fname) 1885 { 1886 FILE *file; 1887 1888 if (error_occurred) 1889 return; 1890 1891 file = fopen(fname, "w"); 1892 if (!file) { 1893 perror(fname); 1894 exit(1); 1895 } 1896 if (fwrite(b->p, 1, b->pos, file) != b->pos) { 1897 perror(fname); 1898 exit(1); 1899 } 1900 if (fclose(file) != 0) { 1901 perror(fname); 1902 exit(1); 1903 } 1904 } 1905 1906 static void write_if_changed(struct buffer *b, const char *fname) 1907 { 1908 char *tmp; 1909 FILE *file; 1910 struct stat st; 1911 1912 file = fopen(fname, "r"); 1913 if (!file) 1914 goto write; 1915 1916 if (fstat(fileno(file), &st) < 0) 1917 goto close_write; 1918 1919 if (st.st_size != b->pos) 1920 goto close_write; 1921 1922 tmp = xmalloc(b->pos); 1923 if (fread(tmp, 1, b->pos, file) != b->pos) 1924 goto free_write; 1925 1926 if (memcmp(tmp, b->p, b->pos) != 0) 1927 goto free_write; 1928 1929 free(tmp); 1930 fclose(file); 1931 return; 1932 1933 free_write: 1934 free(tmp); 1935 close_write: 1936 fclose(file); 1937 write: 1938 write_buf(b, fname); 1939 } 1940 1941 static void write_vmlinux_export_c_file(struct module *mod) 1942 { 1943 struct buffer buf = { }; 1944 1945 buf_printf(&buf, 1946 "#include <linux/export-internal.h>\n"); 1947 1948 add_exported_symbols(&buf, mod); 1949 write_if_changed(&buf, ".vmlinux.export.c"); 1950 free(buf.p); 1951 } 1952 1953 /* do sanity checks, and generate *.mod.c file */ 1954 static void write_mod_c_file(struct module *mod) 1955 { 1956 struct buffer buf = { }; 1957 struct module_alias *alias, *next; 1958 char fname[PATH_MAX]; 1959 int ret; 1960 1961 add_header(&buf, mod); 1962 add_exported_symbols(&buf, mod); 1963 add_versions(&buf, mod); 1964 add_depends(&buf, mod); 1965 1966 buf_printf(&buf, "\n"); 1967 list_for_each_entry_safe(alias, next, &mod->aliases, node) { 1968 buf_printf(&buf, "MODULE_ALIAS(\"%s\");\n", alias->str); 1969 list_del(&alias->node); 1970 free(alias); 1971 } 1972 1973 add_srcversion(&buf, mod); 1974 1975 ret = snprintf(fname, sizeof(fname), "%s.mod.c", mod->name); 1976 if (ret >= sizeof(fname)) { 1977 error("%s: too long path was truncated\n", fname); 1978 goto free; 1979 } 1980 1981 write_if_changed(&buf, fname); 1982 1983 free: 1984 free(buf.p); 1985 } 1986 1987 /* parse Module.symvers file. line format: 1988 * 0x12345678<tab>symbol<tab>module<tab>export<tab>namespace 1989 **/ 1990 static void read_dump(const char *fname) 1991 { 1992 char *buf, *pos, *line; 1993 1994 buf = read_text_file(fname); 1995 if (!buf) 1996 /* No symbol versions, silently ignore */ 1997 return; 1998 1999 pos = buf; 2000 2001 while ((line = get_line(&pos))) { 2002 char *symname, *namespace, *modname, *d, *export; 2003 unsigned int crc; 2004 struct module *mod; 2005 struct symbol *s; 2006 bool gpl_only; 2007 2008 if (!(symname = strchr(line, '\t'))) 2009 goto fail; 2010 *symname++ = '\0'; 2011 if (!(modname = strchr(symname, '\t'))) 2012 goto fail; 2013 *modname++ = '\0'; 2014 if (!(export = strchr(modname, '\t'))) 2015 goto fail; 2016 *export++ = '\0'; 2017 if (!(namespace = strchr(export, '\t'))) 2018 goto fail; 2019 *namespace++ = '\0'; 2020 2021 crc = strtoul(line, &d, 16); 2022 if (*symname == '\0' || *modname == '\0' || *d != '\0') 2023 goto fail; 2024 2025 if (!strcmp(export, "EXPORT_SYMBOL_GPL")) { 2026 gpl_only = true; 2027 } else if (!strcmp(export, "EXPORT_SYMBOL")) { 2028 gpl_only = false; 2029 } else { 2030 error("%s: unknown license %s. skip", symname, export); 2031 continue; 2032 } 2033 2034 mod = find_module(fname, modname); 2035 if (!mod) { 2036 mod = new_module(modname, strlen(modname)); 2037 mod->dump_file = fname; 2038 } 2039 s = sym_add_exported(symname, mod, gpl_only, namespace); 2040 sym_set_crc(s, crc); 2041 } 2042 free(buf); 2043 return; 2044 fail: 2045 free(buf); 2046 fatal("parse error in symbol dump file\n"); 2047 } 2048 2049 static void write_dump(const char *fname) 2050 { 2051 struct buffer buf = { }; 2052 struct module *mod; 2053 struct symbol *sym; 2054 2055 list_for_each_entry(mod, &modules, list) { 2056 if (mod->dump_file) 2057 continue; 2058 list_for_each_entry(sym, &mod->exported_symbols, list) { 2059 if (trim_unused_exports && !sym->used) 2060 continue; 2061 2062 buf_printf(&buf, "0x%08x\t%s\t%s\tEXPORT_SYMBOL%s\t%s\n", 2063 sym->crc, sym->name, mod->name, 2064 sym->is_gpl_only ? "_GPL" : "", 2065 sym->namespace); 2066 } 2067 } 2068 write_buf(&buf, fname); 2069 free(buf.p); 2070 } 2071 2072 static void write_namespace_deps_files(const char *fname) 2073 { 2074 struct module *mod; 2075 struct namespace_list *ns; 2076 struct buffer ns_deps_buf = {}; 2077 2078 list_for_each_entry(mod, &modules, list) { 2079 2080 if (mod->dump_file || list_empty(&mod->missing_namespaces)) 2081 continue; 2082 2083 buf_printf(&ns_deps_buf, "%s.ko:", mod->name); 2084 2085 list_for_each_entry(ns, &mod->missing_namespaces, list) 2086 buf_printf(&ns_deps_buf, " %s", ns->namespace); 2087 2088 buf_printf(&ns_deps_buf, "\n"); 2089 } 2090 2091 write_if_changed(&ns_deps_buf, fname); 2092 free(ns_deps_buf.p); 2093 } 2094 2095 struct dump_list { 2096 struct list_head list; 2097 const char *file; 2098 }; 2099 2100 static void check_host_endian(void) 2101 { 2102 static const union { 2103 short s; 2104 char c[2]; 2105 } endian_test = { .c = {0x01, 0x02} }; 2106 2107 switch (endian_test.s) { 2108 case 0x0102: 2109 host_is_big_endian = true; 2110 break; 2111 case 0x0201: 2112 host_is_big_endian = false; 2113 break; 2114 default: 2115 fatal("Unknown host endian\n"); 2116 } 2117 } 2118 2119 int main(int argc, char **argv) 2120 { 2121 struct module *mod; 2122 char *missing_namespace_deps = NULL; 2123 char *unused_exports_white_list = NULL; 2124 char *dump_write = NULL, *files_source = NULL; 2125 int opt; 2126 LIST_HEAD(dump_lists); 2127 struct dump_list *dl, *dl2; 2128 2129 while ((opt = getopt(argc, argv, "ei:MmnT:to:au:WwENd:")) != -1) { 2130 switch (opt) { 2131 case 'e': 2132 external_module = true; 2133 break; 2134 case 'i': 2135 dl = xmalloc(sizeof(*dl)); 2136 dl->file = optarg; 2137 list_add_tail(&dl->list, &dump_lists); 2138 break; 2139 case 'M': 2140 module_enabled = true; 2141 break; 2142 case 'm': 2143 modversions = true; 2144 break; 2145 case 'n': 2146 ignore_missing_files = true; 2147 break; 2148 case 'o': 2149 dump_write = optarg; 2150 break; 2151 case 'a': 2152 all_versions = true; 2153 break; 2154 case 'T': 2155 files_source = optarg; 2156 break; 2157 case 't': 2158 trim_unused_exports = true; 2159 break; 2160 case 'u': 2161 unused_exports_white_list = optarg; 2162 break; 2163 case 'W': 2164 extra_warn = true; 2165 break; 2166 case 'w': 2167 warn_unresolved = true; 2168 break; 2169 case 'E': 2170 sec_mismatch_warn_only = false; 2171 break; 2172 case 'N': 2173 allow_missing_ns_imports = true; 2174 break; 2175 case 'd': 2176 missing_namespace_deps = optarg; 2177 break; 2178 default: 2179 exit(1); 2180 } 2181 } 2182 2183 check_host_endian(); 2184 2185 list_for_each_entry_safe(dl, dl2, &dump_lists, list) { 2186 read_dump(dl->file); 2187 list_del(&dl->list); 2188 free(dl); 2189 } 2190 2191 while (optind < argc) 2192 read_symbols(argv[optind++]); 2193 2194 if (files_source) 2195 read_symbols_from_files(files_source); 2196 2197 list_for_each_entry(mod, &modules, list) { 2198 if (mod->dump_file || mod->is_vmlinux) 2199 continue; 2200 2201 check_modname_len(mod); 2202 check_exports(mod); 2203 } 2204 2205 if (unused_exports_white_list) 2206 handle_white_list_exports(unused_exports_white_list); 2207 2208 list_for_each_entry(mod, &modules, list) { 2209 if (mod->dump_file) 2210 continue; 2211 2212 if (mod->is_vmlinux) 2213 write_vmlinux_export_c_file(mod); 2214 else 2215 write_mod_c_file(mod); 2216 } 2217 2218 if (missing_namespace_deps) 2219 write_namespace_deps_files(missing_namespace_deps); 2220 2221 if (dump_write) 2222 write_dump(dump_write); 2223 if (sec_mismatch_count && !sec_mismatch_warn_only) 2224 error("Section mismatches detected.\n" 2225 "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n"); 2226 2227 if (nr_unresolved > MAX_UNRESOLVED_REPORTS) 2228 warn("suppressed %u unresolved symbol warnings because there were too many)\n", 2229 nr_unresolved - MAX_UNRESOLVED_REPORTS); 2230 2231 return error_occurred ? 1 : 0; 2232 } 2233