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