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 <hashtable.h> 25 #include <list.h> 26 #include <xalloc.h> 27 #include "modpost.h" 28 #include "../../include/linux/license.h" 29 30 static bool module_enabled; 31 /* Are we using CONFIG_MODVERSIONS? */ 32 static bool modversions; 33 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ 34 static bool all_versions; 35 /* If we are modposting external module set to 1 */ 36 static bool external_module; 37 /* Only warn about unresolved symbols */ 38 static bool warn_unresolved; 39 40 static int sec_mismatch_count; 41 static bool sec_mismatch_warn_only = true; 42 /* Trim EXPORT_SYMBOLs that are unused by in-tree modules */ 43 static bool trim_unused_exports; 44 45 /* ignore missing files */ 46 static bool ignore_missing_files; 47 /* If set to 1, only warn (instead of error) about missing ns imports */ 48 static bool allow_missing_ns_imports; 49 50 static bool error_occurred; 51 52 static bool extra_warn; 53 54 bool target_is_big_endian; 55 bool host_is_big_endian; 56 57 /* 58 * Cut off the warnings when there are too many. This typically occurs when 59 * vmlinux is missing. ('make modules' without building vmlinux.) 60 */ 61 #define MAX_UNRESOLVED_REPORTS 10 62 static unsigned int nr_unresolved; 63 64 /* In kernel, this size is defined in linux/module.h; 65 * here we use Elf_Addr instead of long for covering cross-compile 66 */ 67 68 #define MODULE_NAME_LEN (64 - sizeof(Elf_Addr)) 69 70 void modpost_log(bool is_error, const char *fmt, ...) 71 { 72 va_list arglist; 73 74 if (is_error) { 75 fprintf(stderr, "ERROR: "); 76 error_occurred = true; 77 } else { 78 fprintf(stderr, "WARNING: "); 79 } 80 81 fprintf(stderr, "modpost: "); 82 83 va_start(arglist, fmt); 84 vfprintf(stderr, fmt, arglist); 85 va_end(arglist); 86 } 87 88 static inline bool strends(const char *str, const char *postfix) 89 { 90 if (strlen(str) < strlen(postfix)) 91 return false; 92 93 return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0; 94 } 95 96 char *read_text_file(const char *filename) 97 { 98 struct stat st; 99 size_t nbytes; 100 int fd; 101 char *buf; 102 103 fd = open(filename, O_RDONLY); 104 if (fd < 0) { 105 perror(filename); 106 exit(1); 107 } 108 109 if (fstat(fd, &st) < 0) { 110 perror(filename); 111 exit(1); 112 } 113 114 buf = xmalloc(st.st_size + 1); 115 116 nbytes = st.st_size; 117 118 while (nbytes) { 119 ssize_t bytes_read; 120 121 bytes_read = read(fd, buf, nbytes); 122 if (bytes_read < 0) { 123 perror(filename); 124 exit(1); 125 } 126 127 nbytes -= bytes_read; 128 } 129 buf[st.st_size] = '\0'; 130 131 close(fd); 132 133 return buf; 134 } 135 136 char *get_line(char **stringp) 137 { 138 char *orig = *stringp, *next; 139 140 /* do not return the unwanted extra line at EOF */ 141 if (!orig || *orig == '\0') 142 return NULL; 143 144 /* don't use strsep here, it is not available everywhere */ 145 next = strchr(orig, '\n'); 146 if (next) 147 *next++ = '\0'; 148 149 *stringp = next; 150 151 return orig; 152 } 153 154 /* A list of all modules we processed */ 155 LIST_HEAD(modules); 156 157 static struct module *find_module(const char *modname) 158 { 159 struct module *mod; 160 161 list_for_each_entry(mod, &modules, list) { 162 if (strcmp(mod->name, modname) == 0) 163 return mod; 164 } 165 return NULL; 166 } 167 168 static struct module *new_module(const char *name, size_t namelen) 169 { 170 struct module *mod; 171 172 mod = xmalloc(sizeof(*mod) + namelen + 1); 173 memset(mod, 0, sizeof(*mod)); 174 175 INIT_LIST_HEAD(&mod->exported_symbols); 176 INIT_LIST_HEAD(&mod->unresolved_symbols); 177 INIT_LIST_HEAD(&mod->missing_namespaces); 178 INIT_LIST_HEAD(&mod->imported_namespaces); 179 INIT_LIST_HEAD(&mod->aliases); 180 181 memcpy(mod->name, name, namelen); 182 mod->name[namelen] = '\0'; 183 mod->is_vmlinux = (strcmp(mod->name, "vmlinux") == 0); 184 185 /* 186 * Set mod->is_gpl_compatible to true by default. If MODULE_LICENSE() 187 * is missing, do not check the use for EXPORT_SYMBOL_GPL() becasue 188 * modpost will exit wiht error anyway. 189 */ 190 mod->is_gpl_compatible = true; 191 192 list_add_tail(&mod->list, &modules); 193 194 return mod; 195 } 196 197 struct symbol { 198 struct hlist_node hnode;/* link to hash table */ 199 struct list_head list; /* link to module::exported_symbols or module::unresolved_symbols */ 200 struct module *module; 201 char *namespace; 202 unsigned int crc; 203 bool crc_valid; 204 bool weak; 205 bool is_func; 206 bool is_gpl_only; /* exported by EXPORT_SYMBOL_GPL */ 207 bool used; /* there exists a user of this symbol */ 208 char name[]; 209 }; 210 211 static HASHTABLE_DEFINE(symbol_hashtable, 1U << 10); 212 213 /* This is based on the hash algorithm from gdbm, via tdb */ 214 static inline unsigned int tdb_hash(const char *name) 215 { 216 unsigned value; /* Used to compute the hash value. */ 217 unsigned i; /* Used to cycle through random values. */ 218 219 /* Set the initial value from the key size. */ 220 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++) 221 value = (value + (((unsigned char *)name)[i] << (i*5 % 24))); 222 223 return (1103515243 * value + 12345); 224 } 225 226 /** 227 * Allocate a new symbols for use in the hash of exported symbols or 228 * the list of unresolved symbols per module 229 **/ 230 static struct symbol *alloc_symbol(const char *name) 231 { 232 struct symbol *s = xmalloc(sizeof(*s) + strlen(name) + 1); 233 234 memset(s, 0, sizeof(*s)); 235 strcpy(s->name, name); 236 237 return s; 238 } 239 240 /* For the hash of exported symbols */ 241 static void hash_add_symbol(struct symbol *sym) 242 { 243 hash_add(symbol_hashtable, &sym->hnode, tdb_hash(sym->name)); 244 } 245 246 static void sym_add_unresolved(const char *name, struct module *mod, bool weak) 247 { 248 struct symbol *sym; 249 250 sym = alloc_symbol(name); 251 sym->weak = weak; 252 253 list_add_tail(&sym->list, &mod->unresolved_symbols); 254 } 255 256 static struct symbol *sym_find_with_module(const char *name, struct module *mod) 257 { 258 struct symbol *s; 259 260 /* For our purposes, .foo matches foo. PPC64 needs this. */ 261 if (name[0] == '.') 262 name++; 263 264 hash_for_each_possible(symbol_hashtable, s, hnode, tdb_hash(name)) { 265 if (strcmp(s->name, name) == 0 && (!mod || s->module == mod)) 266 return s; 267 } 268 return NULL; 269 } 270 271 static struct symbol *find_symbol(const char *name) 272 { 273 return sym_find_with_module(name, NULL); 274 } 275 276 struct namespace_list { 277 struct list_head list; 278 char namespace[]; 279 }; 280 281 static bool contains_namespace(struct list_head *head, const char *namespace) 282 { 283 struct namespace_list *list; 284 285 /* 286 * The default namespace is null string "", which is always implicitly 287 * contained. 288 */ 289 if (!namespace[0]) 290 return true; 291 292 list_for_each_entry(list, head, list) { 293 if (!strcmp(list->namespace, namespace)) 294 return true; 295 } 296 297 return false; 298 } 299 300 static void add_namespace(struct list_head *head, const char *namespace) 301 { 302 struct namespace_list *ns_entry; 303 304 if (!contains_namespace(head, namespace)) { 305 ns_entry = xmalloc(sizeof(*ns_entry) + strlen(namespace) + 1); 306 strcpy(ns_entry->namespace, namespace); 307 list_add_tail(&ns_entry->list, head); 308 } 309 } 310 311 static void *sym_get_data_by_offset(const struct elf_info *info, 312 unsigned int secindex, unsigned long offset) 313 { 314 Elf_Shdr *sechdr = &info->sechdrs[secindex]; 315 316 return (void *)info->hdr + sechdr->sh_offset + offset; 317 } 318 319 void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym) 320 { 321 return sym_get_data_by_offset(info, get_secindex(info, sym), 322 sym->st_value); 323 } 324 325 static const char *sech_name(const struct elf_info *info, Elf_Shdr *sechdr) 326 { 327 return sym_get_data_by_offset(info, info->secindex_strings, 328 sechdr->sh_name); 329 } 330 331 static const char *sec_name(const struct elf_info *info, unsigned int secindex) 332 { 333 /* 334 * If sym->st_shndx is a special section index, there is no 335 * corresponding section header. 336 * Return "" if the index is out of range of info->sechdrs[] array. 337 */ 338 if (secindex >= info->num_sections) 339 return ""; 340 341 return sech_name(info, &info->sechdrs[secindex]); 342 } 343 344 static struct symbol *sym_add_exported(const char *name, struct module *mod, 345 bool gpl_only, const char *namespace) 346 { 347 struct symbol *s = find_symbol(name); 348 349 if (s && (!external_module || s->module->is_vmlinux || s->module == mod)) { 350 error("%s: '%s' exported twice. Previous export was in %s%s\n", 351 mod->name, name, s->module->name, 352 s->module->is_vmlinux ? "" : ".ko"); 353 } 354 355 s = alloc_symbol(name); 356 s->module = mod; 357 s->is_gpl_only = gpl_only; 358 s->namespace = xstrdup(namespace); 359 list_add_tail(&s->list, &mod->exported_symbols); 360 hash_add_symbol(s); 361 362 return s; 363 } 364 365 static void sym_set_crc(struct symbol *sym, unsigned int crc) 366 { 367 sym->crc = crc; 368 sym->crc_valid = true; 369 } 370 371 static void *grab_file(const char *filename, size_t *size) 372 { 373 struct stat st; 374 void *map = MAP_FAILED; 375 int fd; 376 377 fd = open(filename, O_RDONLY); 378 if (fd < 0) 379 return NULL; 380 if (fstat(fd, &st)) 381 goto failed; 382 383 *size = st.st_size; 384 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); 385 386 failed: 387 close(fd); 388 if (map == MAP_FAILED) 389 return NULL; 390 return map; 391 } 392 393 static void release_file(void *file, size_t size) 394 { 395 munmap(file, size); 396 } 397 398 static int parse_elf(struct elf_info *info, const char *filename) 399 { 400 unsigned int i; 401 Elf_Ehdr *hdr; 402 Elf_Shdr *sechdrs; 403 Elf_Sym *sym; 404 const char *secstrings; 405 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U; 406 407 hdr = grab_file(filename, &info->size); 408 if (!hdr) { 409 if (ignore_missing_files) { 410 fprintf(stderr, "%s: %s (ignored)\n", filename, 411 strerror(errno)); 412 return 0; 413 } 414 perror(filename); 415 exit(1); 416 } 417 info->hdr = hdr; 418 if (info->size < sizeof(*hdr)) { 419 /* file too small, assume this is an empty .o file */ 420 return 0; 421 } 422 /* Is this a valid ELF file? */ 423 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) || 424 (hdr->e_ident[EI_MAG1] != ELFMAG1) || 425 (hdr->e_ident[EI_MAG2] != ELFMAG2) || 426 (hdr->e_ident[EI_MAG3] != ELFMAG3)) { 427 /* Not an ELF file - silently ignore it */ 428 return 0; 429 } 430 431 switch (hdr->e_ident[EI_DATA]) { 432 case ELFDATA2LSB: 433 target_is_big_endian = false; 434 break; 435 case ELFDATA2MSB: 436 target_is_big_endian = true; 437 break; 438 default: 439 fatal("target endian is unknown\n"); 440 } 441 442 /* Fix endianness in ELF header */ 443 hdr->e_type = TO_NATIVE(hdr->e_type); 444 hdr->e_machine = TO_NATIVE(hdr->e_machine); 445 hdr->e_version = TO_NATIVE(hdr->e_version); 446 hdr->e_entry = TO_NATIVE(hdr->e_entry); 447 hdr->e_phoff = TO_NATIVE(hdr->e_phoff); 448 hdr->e_shoff = TO_NATIVE(hdr->e_shoff); 449 hdr->e_flags = TO_NATIVE(hdr->e_flags); 450 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize); 451 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize); 452 hdr->e_phnum = TO_NATIVE(hdr->e_phnum); 453 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize); 454 hdr->e_shnum = TO_NATIVE(hdr->e_shnum); 455 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx); 456 sechdrs = (void *)hdr + hdr->e_shoff; 457 info->sechdrs = sechdrs; 458 459 /* modpost only works for relocatable objects */ 460 if (hdr->e_type != ET_REL) 461 fatal("%s: not relocatable object.", filename); 462 463 /* Check if file offset is correct */ 464 if (hdr->e_shoff > info->size) 465 fatal("section header offset=%lu in file '%s' is bigger than filesize=%zu\n", 466 (unsigned long)hdr->e_shoff, filename, info->size); 467 468 if (hdr->e_shnum == SHN_UNDEF) { 469 /* 470 * There are more than 64k sections, 471 * read count from .sh_size. 472 */ 473 info->num_sections = TO_NATIVE(sechdrs[0].sh_size); 474 } 475 else { 476 info->num_sections = hdr->e_shnum; 477 } 478 if (hdr->e_shstrndx == SHN_XINDEX) { 479 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link); 480 } 481 else { 482 info->secindex_strings = hdr->e_shstrndx; 483 } 484 485 /* Fix endianness in section headers */ 486 for (i = 0; i < info->num_sections; i++) { 487 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name); 488 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); 489 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags); 490 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr); 491 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset); 492 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size); 493 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link); 494 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info); 495 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign); 496 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize); 497 } 498 /* Find symbol table. */ 499 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset; 500 for (i = 1; i < info->num_sections; i++) { 501 const char *secname; 502 int nobits = sechdrs[i].sh_type == SHT_NOBITS; 503 504 if (!nobits && sechdrs[i].sh_offset > info->size) 505 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > sizeof(*hrd)=%zu\n", 506 filename, (unsigned long)sechdrs[i].sh_offset, 507 sizeof(*hdr)); 508 509 secname = secstrings + sechdrs[i].sh_name; 510 if (strcmp(secname, ".modinfo") == 0) { 511 if (nobits) 512 fatal("%s has NOBITS .modinfo\n", filename); 513 info->modinfo = (void *)hdr + sechdrs[i].sh_offset; 514 info->modinfo_len = sechdrs[i].sh_size; 515 } else if (!strcmp(secname, ".export_symbol")) { 516 info->export_symbol_secndx = i; 517 } 518 519 if (sechdrs[i].sh_type == SHT_SYMTAB) { 520 unsigned int sh_link_idx; 521 symtab_idx = i; 522 info->symtab_start = (void *)hdr + 523 sechdrs[i].sh_offset; 524 info->symtab_stop = (void *)hdr + 525 sechdrs[i].sh_offset + sechdrs[i].sh_size; 526 sh_link_idx = sechdrs[i].sh_link; 527 info->strtab = (void *)hdr + 528 sechdrs[sh_link_idx].sh_offset; 529 } 530 531 /* 32bit section no. table? ("more than 64k sections") */ 532 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) { 533 symtab_shndx_idx = i; 534 info->symtab_shndx_start = (void *)hdr + 535 sechdrs[i].sh_offset; 536 info->symtab_shndx_stop = (void *)hdr + 537 sechdrs[i].sh_offset + sechdrs[i].sh_size; 538 } 539 } 540 if (!info->symtab_start) 541 fatal("%s has no symtab?\n", filename); 542 543 /* Fix endianness in symbols */ 544 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) { 545 sym->st_shndx = TO_NATIVE(sym->st_shndx); 546 sym->st_name = TO_NATIVE(sym->st_name); 547 sym->st_value = TO_NATIVE(sym->st_value); 548 sym->st_size = TO_NATIVE(sym->st_size); 549 } 550 551 if (symtab_shndx_idx != ~0U) { 552 Elf32_Word *p; 553 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link) 554 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n", 555 filename, sechdrs[symtab_shndx_idx].sh_link, 556 symtab_idx); 557 /* Fix endianness */ 558 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop; 559 p++) 560 *p = TO_NATIVE(*p); 561 } 562 563 symsearch_init(info); 564 565 return 1; 566 } 567 568 static void parse_elf_finish(struct elf_info *info) 569 { 570 symsearch_finish(info); 571 release_file(info->hdr, info->size); 572 } 573 574 static int ignore_undef_symbol(struct elf_info *info, const char *symname) 575 { 576 /* ignore __this_module, it will be resolved shortly */ 577 if (strcmp(symname, "__this_module") == 0) 578 return 1; 579 /* ignore global offset table */ 580 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0) 581 return 1; 582 if (info->hdr->e_machine == EM_PPC) 583 /* Special register function linked on all modules during final link of .ko */ 584 if (strstarts(symname, "_restgpr_") || 585 strstarts(symname, "_savegpr_") || 586 strstarts(symname, "_rest32gpr_") || 587 strstarts(symname, "_save32gpr_") || 588 strstarts(symname, "_restvr_") || 589 strstarts(symname, "_savevr_")) 590 return 1; 591 if (info->hdr->e_machine == EM_PPC64) 592 /* Special register function linked on all modules during final link of .ko */ 593 if (strstarts(symname, "_restgpr0_") || 594 strstarts(symname, "_savegpr0_") || 595 strstarts(symname, "_restvr_") || 596 strstarts(symname, "_savevr_") || 597 strcmp(symname, ".TOC.") == 0) 598 return 1; 599 /* Do not ignore this symbol */ 600 return 0; 601 } 602 603 static void handle_symbol(struct module *mod, struct elf_info *info, 604 const Elf_Sym *sym, const char *symname) 605 { 606 switch (sym->st_shndx) { 607 case SHN_COMMON: 608 if (strstarts(symname, "__gnu_lto_")) { 609 /* Should warn here, but modpost runs before the linker */ 610 } else 611 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name); 612 break; 613 case SHN_UNDEF: 614 /* undefined symbol */ 615 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 616 ELF_ST_BIND(sym->st_info) != STB_WEAK) 617 break; 618 if (ignore_undef_symbol(info, symname)) 619 break; 620 if (info->hdr->e_machine == EM_SPARC || 621 info->hdr->e_machine == EM_SPARCV9) { 622 /* Ignore register directives. */ 623 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER) 624 break; 625 if (symname[0] == '.') { 626 char *munged = xstrdup(symname); 627 munged[0] = '_'; 628 munged[1] = toupper(munged[1]); 629 symname = munged; 630 } 631 } 632 633 sym_add_unresolved(symname, mod, 634 ELF_ST_BIND(sym->st_info) == STB_WEAK); 635 break; 636 default: 637 if (strcmp(symname, "init_module") == 0) 638 mod->has_init = true; 639 if (strcmp(symname, "cleanup_module") == 0) 640 mod->has_cleanup = true; 641 break; 642 } 643 } 644 645 /** 646 * Parse tag=value strings from .modinfo section 647 **/ 648 static char *next_string(char *string, unsigned long *secsize) 649 { 650 /* Skip non-zero chars */ 651 while (string[0]) { 652 string++; 653 if ((*secsize)-- <= 1) 654 return NULL; 655 } 656 657 /* Skip any zero padding. */ 658 while (!string[0]) { 659 string++; 660 if ((*secsize)-- <= 1) 661 return NULL; 662 } 663 return string; 664 } 665 666 static char *get_next_modinfo(struct elf_info *info, const char *tag, 667 char *prev) 668 { 669 char *p; 670 unsigned int taglen = strlen(tag); 671 char *modinfo = info->modinfo; 672 unsigned long size = info->modinfo_len; 673 674 if (prev) { 675 size -= prev - modinfo; 676 modinfo = next_string(prev, &size); 677 } 678 679 for (p = modinfo; p; p = next_string(p, &size)) { 680 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') 681 return p + taglen + 1; 682 } 683 return NULL; 684 } 685 686 static char *get_modinfo(struct elf_info *info, const char *tag) 687 688 { 689 return get_next_modinfo(info, tag, NULL); 690 } 691 692 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) 693 { 694 return sym ? elf->strtab + sym->st_name : ""; 695 } 696 697 /* 698 * Check whether the 'string' argument matches one of the 'patterns', 699 * an array of shell wildcard patterns (glob). 700 * 701 * Return true is there is a match. 702 */ 703 static bool match(const char *string, const char *const patterns[]) 704 { 705 const char *pattern; 706 707 while ((pattern = *patterns++)) { 708 if (!fnmatch(pattern, string, 0)) 709 return true; 710 } 711 712 return false; 713 } 714 715 /* useful to pass patterns to match() directly */ 716 #define PATTERNS(...) \ 717 ({ \ 718 static const char *const patterns[] = {__VA_ARGS__, NULL}; \ 719 patterns; \ 720 }) 721 722 /* sections that we do not want to do full section mismatch check on */ 723 static const char *const section_white_list[] = 724 { 725 ".comment*", 726 ".debug*", 727 ".zdebug*", /* Compressed debug sections. */ 728 ".GCC.command.line", /* record-gcc-switches */ 729 ".mdebug*", /* alpha, score, mips etc. */ 730 ".pdr", /* alpha, score, mips etc. */ 731 ".stab*", 732 ".note*", 733 ".got*", 734 ".toc*", 735 ".xt.prop", /* xtensa */ 736 ".xt.lit", /* xtensa */ 737 ".arcextmap*", /* arc */ 738 ".gnu.linkonce.arcext*", /* arc : modules */ 739 ".cmem*", /* EZchip */ 740 ".fmt_slot*", /* EZchip */ 741 ".gnu.lto*", 742 ".discard.*", 743 ".llvm.call-graph-profile", /* call graph */ 744 NULL 745 }; 746 747 /* 748 * This is used to find sections missing the SHF_ALLOC flag. 749 * The cause of this is often a section specified in assembler 750 * without "ax" / "aw". 751 */ 752 static void check_section(const char *modname, struct elf_info *elf, 753 Elf_Shdr *sechdr) 754 { 755 const char *sec = sech_name(elf, sechdr); 756 757 if (sechdr->sh_type == SHT_PROGBITS && 758 !(sechdr->sh_flags & SHF_ALLOC) && 759 !match(sec, section_white_list)) { 760 warn("%s (%s): unexpected non-allocatable section.\n" 761 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n" 762 "Note that for example <linux/init.h> contains\n" 763 "section definitions for use in .S files.\n\n", 764 modname, sec); 765 } 766 } 767 768 769 770 #define ALL_INIT_DATA_SECTIONS \ 771 ".init.setup", ".init.rodata", ".init.data" 772 773 #define ALL_PCI_INIT_SECTIONS \ 774 ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \ 775 ".pci_fixup_enable", ".pci_fixup_resume", \ 776 ".pci_fixup_resume_early", ".pci_fixup_suspend" 777 778 #define ALL_INIT_SECTIONS ".init.*" 779 #define ALL_EXIT_SECTIONS ".exit.*" 780 781 #define DATA_SECTIONS ".data", ".data.rel" 782 #define TEXT_SECTIONS ".text", ".text.*", ".sched.text", \ 783 ".kprobes.text", ".cpuidle.text", ".noinstr.text", \ 784 ".ltext", ".ltext.*" 785 #define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \ 786 ".fixup", ".entry.text", ".exception.text", \ 787 ".coldtext", ".softirqentry.text" 788 789 #define ALL_TEXT_SECTIONS ".init.text", ".exit.text", \ 790 TEXT_SECTIONS, OTHER_TEXT_SECTIONS 791 792 enum mismatch { 793 TEXTDATA_TO_ANY_INIT_EXIT, 794 XXXINIT_TO_SOME_INIT, 795 ANY_INIT_TO_ANY_EXIT, 796 ANY_EXIT_TO_ANY_INIT, 797 EXTABLE_TO_NON_TEXT, 798 }; 799 800 /** 801 * Describe how to match sections on different criteria: 802 * 803 * @fromsec: Array of sections to be matched. 804 * 805 * @bad_tosec: Relocations applied to a section in @fromsec to a section in 806 * this array is forbidden (black-list). Can be empty. 807 * 808 * @good_tosec: Relocations applied to a section in @fromsec must be 809 * targeting sections in this array (white-list). Can be empty. 810 * 811 * @mismatch: Type of mismatch. 812 */ 813 struct sectioncheck { 814 const char *fromsec[20]; 815 const char *bad_tosec[20]; 816 const char *good_tosec[20]; 817 enum mismatch mismatch; 818 }; 819 820 static const struct sectioncheck sectioncheck[] = { 821 /* Do not reference init/exit code/data from 822 * normal code and data 823 */ 824 { 825 .fromsec = { TEXT_SECTIONS, DATA_SECTIONS, NULL }, 826 .bad_tosec = { ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }, 827 .mismatch = TEXTDATA_TO_ANY_INIT_EXIT, 828 }, 829 /* Do not use exit code/data from init code */ 830 { 831 .fromsec = { ALL_INIT_SECTIONS, NULL }, 832 .bad_tosec = { ALL_EXIT_SECTIONS, NULL }, 833 .mismatch = ANY_INIT_TO_ANY_EXIT, 834 }, 835 /* Do not use init code/data from exit code */ 836 { 837 .fromsec = { ALL_EXIT_SECTIONS, NULL }, 838 .bad_tosec = { ALL_INIT_SECTIONS, NULL }, 839 .mismatch = ANY_EXIT_TO_ANY_INIT, 840 }, 841 { 842 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL }, 843 .bad_tosec = { ALL_INIT_SECTIONS, NULL }, 844 .mismatch = ANY_INIT_TO_ANY_EXIT, 845 }, 846 { 847 .fromsec = { "__ex_table", NULL }, 848 /* If you're adding any new black-listed sections in here, consider 849 * adding a special 'printer' for them in scripts/check_extable. 850 */ 851 .bad_tosec = { ".altinstr_replacement", NULL }, 852 .good_tosec = {ALL_TEXT_SECTIONS , NULL}, 853 .mismatch = EXTABLE_TO_NON_TEXT, 854 } 855 }; 856 857 static const struct sectioncheck *section_mismatch( 858 const char *fromsec, const char *tosec) 859 { 860 int i; 861 862 /* 863 * The target section could be the SHT_NUL section when we're 864 * handling relocations to un-resolved symbols, trying to match it 865 * doesn't make much sense and causes build failures on parisc 866 * architectures. 867 */ 868 if (*tosec == '\0') 869 return NULL; 870 871 for (i = 0; i < ARRAY_SIZE(sectioncheck); i++) { 872 const struct sectioncheck *check = §ioncheck[i]; 873 874 if (match(fromsec, check->fromsec)) { 875 if (check->bad_tosec[0] && match(tosec, check->bad_tosec)) 876 return check; 877 if (check->good_tosec[0] && !match(tosec, check->good_tosec)) 878 return check; 879 } 880 } 881 return NULL; 882 } 883 884 /** 885 * Whitelist to allow certain references to pass with no warning. 886 * 887 * Pattern 1: 888 * If a module parameter is declared __initdata and permissions=0 889 * then this is legal despite the warning generated. 890 * We cannot see value of permissions here, so just ignore 891 * this pattern. 892 * The pattern is identified by: 893 * tosec = .init.data 894 * fromsec = .data* 895 * atsym =__param* 896 * 897 * Pattern 1a: 898 * module_param_call() ops can refer to __init set function if permissions=0 899 * The pattern is identified by: 900 * tosec = .init.text 901 * fromsec = .data* 902 * atsym = __param_ops_* 903 * 904 * Pattern 3: 905 * Whitelist all references from .head.text to any init section 906 * 907 * Pattern 4: 908 * Some symbols belong to init section but still it is ok to reference 909 * these from non-init sections as these symbols don't have any memory 910 * allocated for them and symbol address and value are same. So even 911 * if init section is freed, its ok to reference those symbols. 912 * For ex. symbols marking the init section boundaries. 913 * This pattern is identified by 914 * refsymname = __init_begin, _sinittext, _einittext 915 * 916 * Pattern 5: 917 * GCC may optimize static inlines when fed constant arg(s) resulting 918 * in functions like cpumask_empty() -- generating an associated symbol 919 * cpumask_empty.constprop.3 that appears in the audit. If the const that 920 * is passed in comes from __init, like say nmi_ipi_mask, we get a 921 * meaningless section warning. May need to add isra symbols too... 922 * This pattern is identified by 923 * tosec = init section 924 * fromsec = text section 925 * refsymname = *.constprop.* 926 * 927 **/ 928 static int secref_whitelist(const char *fromsec, const char *fromsym, 929 const char *tosec, const char *tosym) 930 { 931 /* Check for pattern 1 */ 932 if (match(tosec, PATTERNS(ALL_INIT_DATA_SECTIONS)) && 933 match(fromsec, PATTERNS(DATA_SECTIONS)) && 934 strstarts(fromsym, "__param")) 935 return 0; 936 937 /* Check for pattern 1a */ 938 if (strcmp(tosec, ".init.text") == 0 && 939 match(fromsec, PATTERNS(DATA_SECTIONS)) && 940 strstarts(fromsym, "__param_ops_")) 941 return 0; 942 943 /* symbols in data sections that may refer to any init/exit sections */ 944 if (match(fromsec, PATTERNS(DATA_SECTIONS)) && 945 match(tosec, PATTERNS(ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS)) && 946 match(fromsym, PATTERNS("*_ops", "*_probe", "*_console"))) 947 return 0; 948 949 /* Check for pattern 3 */ 950 if (strstarts(fromsec, ".head.text") && 951 match(tosec, PATTERNS(ALL_INIT_SECTIONS))) 952 return 0; 953 954 /* Check for pattern 4 */ 955 if (match(tosym, PATTERNS("__init_begin", "_sinittext", "_einittext"))) 956 return 0; 957 958 /* Check for pattern 5 */ 959 if (match(fromsec, PATTERNS(ALL_TEXT_SECTIONS)) && 960 match(tosec, PATTERNS(ALL_INIT_SECTIONS)) && 961 match(fromsym, PATTERNS("*.constprop.*"))) 962 return 0; 963 964 return 1; 965 } 966 967 static Elf_Sym *find_fromsym(struct elf_info *elf, Elf_Addr addr, 968 unsigned int secndx) 969 { 970 return symsearch_find_nearest(elf, addr, secndx, false, ~0); 971 } 972 973 static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym) 974 { 975 Elf_Sym *new_sym; 976 977 /* If the supplied symbol has a valid name, return it */ 978 if (is_valid_name(elf, sym)) 979 return sym; 980 981 /* 982 * Strive to find a better symbol name, but the resulting name may not 983 * match the symbol referenced in the original code. 984 */ 985 new_sym = symsearch_find_nearest(elf, addr, get_secindex(elf, sym), 986 true, 20); 987 return new_sym ? new_sym : sym; 988 } 989 990 static bool is_executable_section(struct elf_info *elf, unsigned int secndx) 991 { 992 if (secndx >= elf->num_sections) 993 return false; 994 995 return (elf->sechdrs[secndx].sh_flags & SHF_EXECINSTR) != 0; 996 } 997 998 static void default_mismatch_handler(const char *modname, struct elf_info *elf, 999 const struct sectioncheck* const mismatch, 1000 Elf_Sym *tsym, 1001 unsigned int fsecndx, const char *fromsec, Elf_Addr faddr, 1002 const char *tosec, Elf_Addr taddr) 1003 { 1004 Elf_Sym *from; 1005 const char *tosym; 1006 const char *fromsym; 1007 char taddr_str[16]; 1008 1009 from = find_fromsym(elf, faddr, fsecndx); 1010 fromsym = sym_name(elf, from); 1011 1012 tsym = find_tosym(elf, taddr, tsym); 1013 tosym = sym_name(elf, tsym); 1014 1015 /* check whitelist - we may ignore it */ 1016 if (!secref_whitelist(fromsec, fromsym, tosec, tosym)) 1017 return; 1018 1019 sec_mismatch_count++; 1020 1021 if (!tosym[0]) 1022 snprintf(taddr_str, sizeof(taddr_str), "0x%x", (unsigned int)taddr); 1023 1024 /* 1025 * The format for the reference source: <symbol_name>+<offset> or <address> 1026 * The format for the reference destination: <symbol_name> or <address> 1027 */ 1028 warn("%s: section mismatch in reference: %s%s0x%x (section: %s) -> %s (section: %s)\n", 1029 modname, fromsym, fromsym[0] ? "+" : "", 1030 (unsigned int)(faddr - (fromsym[0] ? from->st_value : 0)), 1031 fromsec, tosym[0] ? tosym : taddr_str, tosec); 1032 1033 if (mismatch->mismatch == EXTABLE_TO_NON_TEXT) { 1034 if (match(tosec, mismatch->bad_tosec)) 1035 fatal("The relocation at %s+0x%lx references\n" 1036 "section \"%s\" which is black-listed.\n" 1037 "Something is seriously wrong and should be fixed.\n" 1038 "You might get more information about where this is\n" 1039 "coming from by using scripts/check_extable.sh %s\n", 1040 fromsec, (long)faddr, tosec, modname); 1041 else if (is_executable_section(elf, get_secindex(elf, tsym))) 1042 warn("The relocation at %s+0x%lx references\n" 1043 "section \"%s\" which is not in the list of\n" 1044 "authorized sections. If you're adding a new section\n" 1045 "and/or if this reference is valid, add \"%s\" to the\n" 1046 "list of authorized sections to jump to on fault.\n" 1047 "This can be achieved by adding \"%s\" to\n" 1048 "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n", 1049 fromsec, (long)faddr, tosec, tosec, tosec); 1050 else 1051 error("%s+0x%lx references non-executable section '%s'\n", 1052 fromsec, (long)faddr, tosec); 1053 } 1054 } 1055 1056 static void check_export_symbol(struct module *mod, struct elf_info *elf, 1057 Elf_Addr faddr, const char *secname, 1058 Elf_Sym *sym) 1059 { 1060 static const char *prefix = "__export_symbol_"; 1061 const char *label_name, *name, *data; 1062 Elf_Sym *label; 1063 struct symbol *s; 1064 bool is_gpl; 1065 1066 label = find_fromsym(elf, faddr, elf->export_symbol_secndx); 1067 label_name = sym_name(elf, label); 1068 1069 if (!strstarts(label_name, prefix)) { 1070 error("%s: .export_symbol section contains strange symbol '%s'\n", 1071 mod->name, label_name); 1072 return; 1073 } 1074 1075 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 1076 ELF_ST_BIND(sym->st_info) != STB_WEAK) { 1077 error("%s: local symbol '%s' was exported\n", mod->name, 1078 label_name + strlen(prefix)); 1079 return; 1080 } 1081 1082 name = sym_name(elf, sym); 1083 if (strcmp(label_name + strlen(prefix), name)) { 1084 error("%s: .export_symbol section references '%s', but it does not seem to be an export symbol\n", 1085 mod->name, name); 1086 return; 1087 } 1088 1089 data = sym_get_data(elf, label); /* license */ 1090 if (!strcmp(data, "GPL")) { 1091 is_gpl = true; 1092 } else if (!strcmp(data, "")) { 1093 is_gpl = false; 1094 } else { 1095 error("%s: unknown license '%s' was specified for '%s'\n", 1096 mod->name, data, name); 1097 return; 1098 } 1099 1100 data += strlen(data) + 1; /* namespace */ 1101 s = sym_add_exported(name, mod, is_gpl, data); 1102 1103 /* 1104 * We need to be aware whether we are exporting a function or 1105 * a data on some architectures. 1106 */ 1107 s->is_func = (ELF_ST_TYPE(sym->st_info) == STT_FUNC); 1108 1109 /* 1110 * For parisc64, symbols prefixed $$ from the library have the symbol type 1111 * STT_LOPROC. They should be handled as functions too. 1112 */ 1113 if (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64 && 1114 elf->hdr->e_machine == EM_PARISC && 1115 ELF_ST_TYPE(sym->st_info) == STT_LOPROC) 1116 s->is_func = true; 1117 1118 if (match(secname, PATTERNS(ALL_INIT_SECTIONS))) 1119 warn("%s: %s: EXPORT_SYMBOL used for init symbol. Remove __init or EXPORT_SYMBOL.\n", 1120 mod->name, name); 1121 else if (match(secname, PATTERNS(ALL_EXIT_SECTIONS))) 1122 warn("%s: %s: EXPORT_SYMBOL used for exit symbol. Remove __exit or EXPORT_SYMBOL.\n", 1123 mod->name, name); 1124 } 1125 1126 static void check_section_mismatch(struct module *mod, struct elf_info *elf, 1127 Elf_Sym *sym, 1128 unsigned int fsecndx, const char *fromsec, 1129 Elf_Addr faddr, Elf_Addr taddr) 1130 { 1131 const char *tosec = sec_name(elf, get_secindex(elf, sym)); 1132 const struct sectioncheck *mismatch; 1133 1134 if (module_enabled && elf->export_symbol_secndx == fsecndx) { 1135 check_export_symbol(mod, elf, faddr, tosec, sym); 1136 return; 1137 } 1138 1139 mismatch = section_mismatch(fromsec, tosec); 1140 if (!mismatch) 1141 return; 1142 1143 default_mismatch_handler(mod->name, elf, mismatch, sym, 1144 fsecndx, fromsec, faddr, 1145 tosec, taddr); 1146 } 1147 1148 static Elf_Addr addend_386_rel(uint32_t *location, unsigned int r_type) 1149 { 1150 switch (r_type) { 1151 case R_386_32: 1152 return TO_NATIVE(*location); 1153 case R_386_PC32: 1154 return TO_NATIVE(*location) + 4; 1155 } 1156 1157 return (Elf_Addr)(-1); 1158 } 1159 1160 static int32_t sign_extend32(int32_t value, int index) 1161 { 1162 uint8_t shift = 31 - index; 1163 1164 return (int32_t)(value << shift) >> shift; 1165 } 1166 1167 static Elf_Addr addend_arm_rel(void *loc, Elf_Sym *sym, unsigned int r_type) 1168 { 1169 uint32_t inst, upper, lower, sign, j1, j2; 1170 int32_t offset; 1171 1172 switch (r_type) { 1173 case R_ARM_ABS32: 1174 case R_ARM_REL32: 1175 inst = TO_NATIVE(*(uint32_t *)loc); 1176 return inst + sym->st_value; 1177 case R_ARM_MOVW_ABS_NC: 1178 case R_ARM_MOVT_ABS: 1179 inst = TO_NATIVE(*(uint32_t *)loc); 1180 offset = sign_extend32(((inst & 0xf0000) >> 4) | (inst & 0xfff), 1181 15); 1182 return offset + sym->st_value; 1183 case R_ARM_PC24: 1184 case R_ARM_CALL: 1185 case R_ARM_JUMP24: 1186 inst = TO_NATIVE(*(uint32_t *)loc); 1187 offset = sign_extend32((inst & 0x00ffffff) << 2, 25); 1188 return offset + sym->st_value + 8; 1189 case R_ARM_THM_MOVW_ABS_NC: 1190 case R_ARM_THM_MOVT_ABS: 1191 upper = TO_NATIVE(*(uint16_t *)loc); 1192 lower = TO_NATIVE(*((uint16_t *)loc + 1)); 1193 offset = sign_extend32(((upper & 0x000f) << 12) | 1194 ((upper & 0x0400) << 1) | 1195 ((lower & 0x7000) >> 4) | 1196 (lower & 0x00ff), 1197 15); 1198 return offset + sym->st_value; 1199 case R_ARM_THM_JUMP19: 1200 /* 1201 * Encoding T3: 1202 * S = upper[10] 1203 * imm6 = upper[5:0] 1204 * J1 = lower[13] 1205 * J2 = lower[11] 1206 * imm11 = lower[10:0] 1207 * imm32 = SignExtend(S:J2:J1:imm6:imm11:'0') 1208 */ 1209 upper = TO_NATIVE(*(uint16_t *)loc); 1210 lower = TO_NATIVE(*((uint16_t *)loc + 1)); 1211 1212 sign = (upper >> 10) & 1; 1213 j1 = (lower >> 13) & 1; 1214 j2 = (lower >> 11) & 1; 1215 offset = sign_extend32((sign << 20) | (j2 << 19) | (j1 << 18) | 1216 ((upper & 0x03f) << 12) | 1217 ((lower & 0x07ff) << 1), 1218 20); 1219 return offset + sym->st_value + 4; 1220 case R_ARM_THM_PC22: 1221 case R_ARM_THM_JUMP24: 1222 /* 1223 * Encoding T4: 1224 * S = upper[10] 1225 * imm10 = upper[9:0] 1226 * J1 = lower[13] 1227 * J2 = lower[11] 1228 * imm11 = lower[10:0] 1229 * I1 = NOT(J1 XOR S) 1230 * I2 = NOT(J2 XOR S) 1231 * imm32 = SignExtend(S:I1:I2:imm10:imm11:'0') 1232 */ 1233 upper = TO_NATIVE(*(uint16_t *)loc); 1234 lower = TO_NATIVE(*((uint16_t *)loc + 1)); 1235 1236 sign = (upper >> 10) & 1; 1237 j1 = (lower >> 13) & 1; 1238 j2 = (lower >> 11) & 1; 1239 offset = sign_extend32((sign << 24) | 1240 ((~(j1 ^ sign) & 1) << 23) | 1241 ((~(j2 ^ sign) & 1) << 22) | 1242 ((upper & 0x03ff) << 12) | 1243 ((lower & 0x07ff) << 1), 1244 24); 1245 return offset + sym->st_value + 4; 1246 } 1247 1248 return (Elf_Addr)(-1); 1249 } 1250 1251 static Elf_Addr addend_mips_rel(uint32_t *location, unsigned int r_type) 1252 { 1253 uint32_t inst; 1254 1255 inst = TO_NATIVE(*location); 1256 switch (r_type) { 1257 case R_MIPS_LO16: 1258 return inst & 0xffff; 1259 case R_MIPS_26: 1260 return (inst & 0x03ffffff) << 2; 1261 case R_MIPS_32: 1262 return inst; 1263 } 1264 return (Elf_Addr)(-1); 1265 } 1266 1267 #ifndef EM_RISCV 1268 #define EM_RISCV 243 1269 #endif 1270 1271 #ifndef R_RISCV_SUB32 1272 #define R_RISCV_SUB32 39 1273 #endif 1274 1275 #ifndef EM_LOONGARCH 1276 #define EM_LOONGARCH 258 1277 #endif 1278 1279 #ifndef R_LARCH_SUB32 1280 #define R_LARCH_SUB32 55 1281 #endif 1282 1283 #ifndef R_LARCH_RELAX 1284 #define R_LARCH_RELAX 100 1285 #endif 1286 1287 #ifndef R_LARCH_ALIGN 1288 #define R_LARCH_ALIGN 102 1289 #endif 1290 1291 static void get_rel_type_and_sym(struct elf_info *elf, uint64_t r_info, 1292 unsigned int *r_type, unsigned int *r_sym) 1293 { 1294 typedef struct { 1295 Elf64_Word r_sym; /* Symbol index */ 1296 unsigned char r_ssym; /* Special symbol for 2nd relocation */ 1297 unsigned char r_type3; /* 3rd relocation type */ 1298 unsigned char r_type2; /* 2nd relocation type */ 1299 unsigned char r_type; /* 1st relocation type */ 1300 } Elf64_Mips_R_Info; 1301 1302 bool is_64bit = (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64); 1303 1304 if (elf->hdr->e_machine == EM_MIPS && is_64bit) { 1305 Elf64_Mips_R_Info *mips64_r_info = (void *)&r_info; 1306 1307 *r_type = mips64_r_info->r_type; 1308 *r_sym = TO_NATIVE(mips64_r_info->r_sym); 1309 return; 1310 } 1311 1312 if (is_64bit) 1313 r_info = TO_NATIVE((Elf64_Xword)r_info); 1314 else 1315 r_info = TO_NATIVE((Elf32_Word)r_info); 1316 1317 *r_type = ELF_R_TYPE(r_info); 1318 *r_sym = ELF_R_SYM(r_info); 1319 } 1320 1321 static void section_rela(struct module *mod, struct elf_info *elf, 1322 unsigned int fsecndx, const char *fromsec, 1323 const Elf_Rela *start, const Elf_Rela *stop) 1324 { 1325 const Elf_Rela *rela; 1326 1327 for (rela = start; rela < stop; rela++) { 1328 Elf_Sym *tsym; 1329 Elf_Addr taddr, r_offset; 1330 unsigned int r_type, r_sym; 1331 1332 r_offset = TO_NATIVE(rela->r_offset); 1333 get_rel_type_and_sym(elf, rela->r_info, &r_type, &r_sym); 1334 1335 tsym = elf->symtab_start + r_sym; 1336 taddr = tsym->st_value + TO_NATIVE(rela->r_addend); 1337 1338 switch (elf->hdr->e_machine) { 1339 case EM_RISCV: 1340 if (!strcmp("__ex_table", fromsec) && 1341 r_type == R_RISCV_SUB32) 1342 continue; 1343 break; 1344 case EM_LOONGARCH: 1345 switch (r_type) { 1346 case R_LARCH_SUB32: 1347 if (!strcmp("__ex_table", fromsec)) 1348 continue; 1349 break; 1350 case R_LARCH_RELAX: 1351 case R_LARCH_ALIGN: 1352 /* These relocs do not refer to symbols */ 1353 continue; 1354 } 1355 break; 1356 } 1357 1358 check_section_mismatch(mod, elf, tsym, 1359 fsecndx, fromsec, r_offset, taddr); 1360 } 1361 } 1362 1363 static void section_rel(struct module *mod, struct elf_info *elf, 1364 unsigned int fsecndx, const char *fromsec, 1365 const Elf_Rel *start, const Elf_Rel *stop) 1366 { 1367 const Elf_Rel *rel; 1368 1369 for (rel = start; rel < stop; rel++) { 1370 Elf_Sym *tsym; 1371 Elf_Addr taddr, r_offset; 1372 unsigned int r_type, r_sym; 1373 void *loc; 1374 1375 r_offset = TO_NATIVE(rel->r_offset); 1376 get_rel_type_and_sym(elf, rel->r_info, &r_type, &r_sym); 1377 1378 loc = sym_get_data_by_offset(elf, fsecndx, r_offset); 1379 tsym = elf->symtab_start + r_sym; 1380 1381 switch (elf->hdr->e_machine) { 1382 case EM_386: 1383 taddr = addend_386_rel(loc, r_type); 1384 break; 1385 case EM_ARM: 1386 taddr = addend_arm_rel(loc, tsym, r_type); 1387 break; 1388 case EM_MIPS: 1389 taddr = addend_mips_rel(loc, r_type); 1390 break; 1391 default: 1392 fatal("Please add code to calculate addend for this architecture\n"); 1393 } 1394 1395 check_section_mismatch(mod, elf, tsym, 1396 fsecndx, fromsec, r_offset, taddr); 1397 } 1398 } 1399 1400 /** 1401 * A module includes a number of sections that are discarded 1402 * either when loaded or when used as built-in. 1403 * For loaded modules all functions marked __init and all data 1404 * marked __initdata will be discarded when the module has been initialized. 1405 * Likewise for modules used built-in the sections marked __exit 1406 * are discarded because __exit marked function are supposed to be called 1407 * only when a module is unloaded which never happens for built-in modules. 1408 * The check_sec_ref() function traverses all relocation records 1409 * to find all references to a section that reference a section that will 1410 * be discarded and warns about it. 1411 **/ 1412 static void check_sec_ref(struct module *mod, struct elf_info *elf) 1413 { 1414 int i; 1415 1416 /* Walk through all sections */ 1417 for (i = 0; i < elf->num_sections; i++) { 1418 Elf_Shdr *sechdr = &elf->sechdrs[i]; 1419 1420 check_section(mod->name, elf, sechdr); 1421 /* We want to process only relocation sections and not .init */ 1422 if (sechdr->sh_type == SHT_REL || sechdr->sh_type == SHT_RELA) { 1423 /* section to which the relocation applies */ 1424 unsigned int secndx = sechdr->sh_info; 1425 const char *secname = sec_name(elf, secndx); 1426 const void *start, *stop; 1427 1428 /* If the section is known good, skip it */ 1429 if (match(secname, section_white_list)) 1430 continue; 1431 1432 start = sym_get_data_by_offset(elf, i, 0); 1433 stop = start + sechdr->sh_size; 1434 1435 if (sechdr->sh_type == SHT_RELA) 1436 section_rela(mod, elf, secndx, secname, 1437 start, stop); 1438 else 1439 section_rel(mod, elf, secndx, secname, 1440 start, stop); 1441 } 1442 } 1443 } 1444 1445 static char *remove_dot(char *s) 1446 { 1447 size_t n = strcspn(s, "."); 1448 1449 if (n && s[n]) { 1450 size_t m = strspn(s + n + 1, "0123456789"); 1451 if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0)) 1452 s[n] = 0; 1453 } 1454 return s; 1455 } 1456 1457 /* 1458 * The CRCs are recorded in .*.cmd files in the form of: 1459 * #SYMVER <name> <crc> 1460 */ 1461 static void extract_crcs_for_object(const char *object, struct module *mod) 1462 { 1463 char cmd_file[PATH_MAX]; 1464 char *buf, *p; 1465 const char *base; 1466 int dirlen, ret; 1467 1468 base = strrchr(object, '/'); 1469 if (base) { 1470 base++; 1471 dirlen = base - object; 1472 } else { 1473 dirlen = 0; 1474 base = object; 1475 } 1476 1477 ret = snprintf(cmd_file, sizeof(cmd_file), "%.*s.%s.cmd", 1478 dirlen, object, base); 1479 if (ret >= sizeof(cmd_file)) { 1480 error("%s: too long path was truncated\n", cmd_file); 1481 return; 1482 } 1483 1484 buf = read_text_file(cmd_file); 1485 p = buf; 1486 1487 while ((p = strstr(p, "\n#SYMVER "))) { 1488 char *name; 1489 size_t namelen; 1490 unsigned int crc; 1491 struct symbol *sym; 1492 1493 name = p + strlen("\n#SYMVER "); 1494 1495 p = strchr(name, ' '); 1496 if (!p) 1497 break; 1498 1499 namelen = p - name; 1500 p++; 1501 1502 if (!isdigit(*p)) 1503 continue; /* skip this line */ 1504 1505 crc = strtoul(p, &p, 0); 1506 if (*p != '\n') 1507 continue; /* skip this line */ 1508 1509 name[namelen] = '\0'; 1510 1511 /* 1512 * sym_find_with_module() may return NULL here. 1513 * It typically occurs when CONFIG_TRIM_UNUSED_KSYMS=y. 1514 * Since commit e1327a127703, genksyms calculates CRCs of all 1515 * symbols, including trimmed ones. Ignore orphan CRCs. 1516 */ 1517 sym = sym_find_with_module(name, mod); 1518 if (sym) 1519 sym_set_crc(sym, crc); 1520 } 1521 1522 free(buf); 1523 } 1524 1525 /* 1526 * The symbol versions (CRC) are recorded in the .*.cmd files. 1527 * Parse them to retrieve CRCs for the current module. 1528 */ 1529 static void mod_set_crcs(struct module *mod) 1530 { 1531 char objlist[PATH_MAX]; 1532 char *buf, *p, *obj; 1533 int ret; 1534 1535 if (mod->is_vmlinux) { 1536 strcpy(objlist, ".vmlinux.objs"); 1537 } else { 1538 /* objects for a module are listed in the *.mod file. */ 1539 ret = snprintf(objlist, sizeof(objlist), "%s.mod", mod->name); 1540 if (ret >= sizeof(objlist)) { 1541 error("%s: too long path was truncated\n", objlist); 1542 return; 1543 } 1544 } 1545 1546 buf = read_text_file(objlist); 1547 p = buf; 1548 1549 while ((obj = strsep(&p, "\n")) && obj[0]) 1550 extract_crcs_for_object(obj, mod); 1551 1552 free(buf); 1553 } 1554 1555 static void read_symbols(const char *modname) 1556 { 1557 const char *symname; 1558 char *version; 1559 char *license; 1560 char *namespace; 1561 struct module *mod; 1562 struct elf_info info = { }; 1563 Elf_Sym *sym; 1564 1565 if (!parse_elf(&info, modname)) 1566 return; 1567 1568 if (!strends(modname, ".o")) { 1569 error("%s: filename must be suffixed with .o\n", modname); 1570 return; 1571 } 1572 1573 /* strip trailing .o */ 1574 mod = new_module(modname, strlen(modname) - strlen(".o")); 1575 1576 if (!mod->is_vmlinux) { 1577 license = get_modinfo(&info, "license"); 1578 if (!license) 1579 error("missing MODULE_LICENSE() in %s\n", modname); 1580 while (license) { 1581 if (!license_is_gpl_compatible(license)) { 1582 mod->is_gpl_compatible = false; 1583 break; 1584 } 1585 license = get_next_modinfo(&info, "license", license); 1586 } 1587 1588 namespace = get_modinfo(&info, "import_ns"); 1589 while (namespace) { 1590 add_namespace(&mod->imported_namespaces, namespace); 1591 namespace = get_next_modinfo(&info, "import_ns", 1592 namespace); 1593 } 1594 1595 if (extra_warn && !get_modinfo(&info, "description")) 1596 warn("missing MODULE_DESCRIPTION() in %s\n", modname); 1597 } 1598 1599 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { 1600 symname = remove_dot(info.strtab + sym->st_name); 1601 1602 handle_symbol(mod, &info, sym, symname); 1603 handle_moddevtable(mod, &info, sym, symname); 1604 } 1605 1606 check_sec_ref(mod, &info); 1607 1608 if (!mod->is_vmlinux) { 1609 version = get_modinfo(&info, "version"); 1610 if (version || all_versions) 1611 get_src_version(mod->name, mod->srcversion, 1612 sizeof(mod->srcversion) - 1); 1613 } 1614 1615 parse_elf_finish(&info); 1616 1617 if (modversions) { 1618 /* 1619 * Our trick to get versioning for module struct etc. - it's 1620 * never passed as an argument to an exported function, so 1621 * the automatic versioning doesn't pick it up, but it's really 1622 * important anyhow. 1623 */ 1624 sym_add_unresolved("module_layout", mod, false); 1625 1626 mod_set_crcs(mod); 1627 } 1628 } 1629 1630 static void read_symbols_from_files(const char *filename) 1631 { 1632 FILE *in = stdin; 1633 char fname[PATH_MAX]; 1634 1635 in = fopen(filename, "r"); 1636 if (!in) 1637 fatal("Can't open filenames file %s: %m", filename); 1638 1639 while (fgets(fname, PATH_MAX, in) != NULL) { 1640 if (strends(fname, "\n")) 1641 fname[strlen(fname)-1] = '\0'; 1642 read_symbols(fname); 1643 } 1644 1645 fclose(in); 1646 } 1647 1648 #define SZ 500 1649 1650 /* We first write the generated file into memory using the 1651 * following helper, then compare to the file on disk and 1652 * only update the later if anything changed */ 1653 1654 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf, 1655 const char *fmt, ...) 1656 { 1657 char tmp[SZ]; 1658 int len; 1659 va_list ap; 1660 1661 va_start(ap, fmt); 1662 len = vsnprintf(tmp, SZ, fmt, ap); 1663 buf_write(buf, tmp, len); 1664 va_end(ap); 1665 } 1666 1667 void buf_write(struct buffer *buf, const char *s, int len) 1668 { 1669 if (buf->size - buf->pos < len) { 1670 buf->size += len + SZ; 1671 buf->p = xrealloc(buf->p, buf->size); 1672 } 1673 strncpy(buf->p + buf->pos, s, len); 1674 buf->pos += len; 1675 } 1676 1677 static void check_exports(struct module *mod) 1678 { 1679 struct symbol *s, *exp; 1680 1681 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1682 const char *basename; 1683 exp = find_symbol(s->name); 1684 if (!exp) { 1685 if (!s->weak && nr_unresolved++ < MAX_UNRESOLVED_REPORTS) 1686 modpost_log(!warn_unresolved, 1687 "\"%s\" [%s.ko] undefined!\n", 1688 s->name, mod->name); 1689 continue; 1690 } 1691 if (exp->module == mod) { 1692 error("\"%s\" [%s.ko] was exported without definition\n", 1693 s->name, mod->name); 1694 continue; 1695 } 1696 1697 exp->used = true; 1698 s->module = exp->module; 1699 s->crc_valid = exp->crc_valid; 1700 s->crc = exp->crc; 1701 1702 basename = strrchr(mod->name, '/'); 1703 if (basename) 1704 basename++; 1705 else 1706 basename = mod->name; 1707 1708 if (!contains_namespace(&mod->imported_namespaces, exp->namespace)) { 1709 modpost_log(!allow_missing_ns_imports, 1710 "module %s uses symbol %s from namespace %s, but does not import it.\n", 1711 basename, exp->name, exp->namespace); 1712 add_namespace(&mod->missing_namespaces, exp->namespace); 1713 } 1714 1715 if (!mod->is_gpl_compatible && exp->is_gpl_only) 1716 error("GPL-incompatible module %s.ko uses GPL-only symbol '%s'\n", 1717 basename, exp->name); 1718 } 1719 } 1720 1721 static void handle_white_list_exports(const char *white_list) 1722 { 1723 char *buf, *p, *name; 1724 1725 buf = read_text_file(white_list); 1726 p = buf; 1727 1728 while ((name = strsep(&p, "\n"))) { 1729 struct symbol *sym = find_symbol(name); 1730 1731 if (sym) 1732 sym->used = true; 1733 } 1734 1735 free(buf); 1736 } 1737 1738 static void check_modname_len(struct module *mod) 1739 { 1740 const char *mod_name; 1741 1742 mod_name = strrchr(mod->name, '/'); 1743 if (mod_name == NULL) 1744 mod_name = mod->name; 1745 else 1746 mod_name++; 1747 if (strlen(mod_name) >= MODULE_NAME_LEN) 1748 error("module name is too long [%s.ko]\n", mod->name); 1749 } 1750 1751 /** 1752 * Header for the generated file 1753 **/ 1754 static void add_header(struct buffer *b, struct module *mod) 1755 { 1756 buf_printf(b, "#include <linux/module.h>\n"); 1757 buf_printf(b, "#include <linux/export-internal.h>\n"); 1758 buf_printf(b, "#include <linux/compiler.h>\n"); 1759 buf_printf(b, "\n"); 1760 buf_printf(b, "MODULE_INFO(name, KBUILD_MODNAME);\n"); 1761 buf_printf(b, "\n"); 1762 buf_printf(b, "__visible struct module __this_module\n"); 1763 buf_printf(b, "__section(\".gnu.linkonce.this_module\") = {\n"); 1764 buf_printf(b, "\t.name = KBUILD_MODNAME,\n"); 1765 if (mod->has_init) 1766 buf_printf(b, "\t.init = init_module,\n"); 1767 if (mod->has_cleanup) 1768 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n" 1769 "\t.exit = cleanup_module,\n" 1770 "#endif\n"); 1771 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n"); 1772 buf_printf(b, "};\n"); 1773 1774 if (!external_module) 1775 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n"); 1776 1777 if (strstarts(mod->name, "drivers/staging")) 1778 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); 1779 1780 if (strstarts(mod->name, "tools/testing")) 1781 buf_printf(b, "\nMODULE_INFO(test, \"Y\");\n"); 1782 } 1783 1784 static void add_exported_symbols(struct buffer *buf, struct module *mod) 1785 { 1786 struct symbol *sym; 1787 1788 /* generate struct for exported symbols */ 1789 buf_printf(buf, "\n"); 1790 list_for_each_entry(sym, &mod->exported_symbols, list) { 1791 if (trim_unused_exports && !sym->used) 1792 continue; 1793 1794 buf_printf(buf, "KSYMTAB_%s(%s, \"%s\", \"%s\");\n", 1795 sym->is_func ? "FUNC" : "DATA", sym->name, 1796 sym->is_gpl_only ? "_gpl" : "", sym->namespace); 1797 } 1798 1799 if (!modversions) 1800 return; 1801 1802 /* record CRCs for exported symbols */ 1803 buf_printf(buf, "\n"); 1804 list_for_each_entry(sym, &mod->exported_symbols, list) { 1805 if (trim_unused_exports && !sym->used) 1806 continue; 1807 1808 if (!sym->crc_valid) 1809 warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n" 1810 "Is \"%s\" prototyped in <asm/asm-prototypes.h>?\n", 1811 sym->name, mod->name, mod->is_vmlinux ? "" : ".ko", 1812 sym->name); 1813 1814 buf_printf(buf, "SYMBOL_CRC(%s, 0x%08x, \"%s\");\n", 1815 sym->name, sym->crc, sym->is_gpl_only ? "_gpl" : ""); 1816 } 1817 } 1818 1819 /** 1820 * Record CRCs for unresolved symbols 1821 **/ 1822 static void add_versions(struct buffer *b, struct module *mod) 1823 { 1824 struct symbol *s; 1825 1826 if (!modversions) 1827 return; 1828 1829 buf_printf(b, "\n"); 1830 buf_printf(b, "static const struct modversion_info ____versions[]\n"); 1831 buf_printf(b, "__used __section(\"__versions\") = {\n"); 1832 1833 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1834 if (!s->module) 1835 continue; 1836 if (!s->crc_valid) { 1837 warn("\"%s\" [%s.ko] has no CRC!\n", 1838 s->name, mod->name); 1839 continue; 1840 } 1841 if (strlen(s->name) >= MODULE_NAME_LEN) { 1842 error("too long symbol \"%s\" [%s.ko]\n", 1843 s->name, mod->name); 1844 break; 1845 } 1846 buf_printf(b, "\t{ %#8x, \"%s\" },\n", 1847 s->crc, s->name); 1848 } 1849 1850 buf_printf(b, "};\n"); 1851 } 1852 1853 static void add_depends(struct buffer *b, struct module *mod) 1854 { 1855 struct symbol *s; 1856 int first = 1; 1857 1858 /* Clear ->seen flag of modules that own symbols needed by this. */ 1859 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1860 if (s->module) 1861 s->module->seen = s->module->is_vmlinux; 1862 } 1863 1864 buf_printf(b, "\n"); 1865 buf_printf(b, "MODULE_INFO(depends, \""); 1866 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1867 const char *p; 1868 if (!s->module) 1869 continue; 1870 1871 if (s->module->seen) 1872 continue; 1873 1874 s->module->seen = true; 1875 p = strrchr(s->module->name, '/'); 1876 if (p) 1877 p++; 1878 else 1879 p = s->module->name; 1880 buf_printf(b, "%s%s", first ? "" : ",", p); 1881 first = 0; 1882 } 1883 buf_printf(b, "\");\n"); 1884 } 1885 1886 static void add_srcversion(struct buffer *b, struct module *mod) 1887 { 1888 if (mod->srcversion[0]) { 1889 buf_printf(b, "\n"); 1890 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n", 1891 mod->srcversion); 1892 } 1893 } 1894 1895 static void write_buf(struct buffer *b, const char *fname) 1896 { 1897 FILE *file; 1898 1899 if (error_occurred) 1900 return; 1901 1902 file = fopen(fname, "w"); 1903 if (!file) { 1904 perror(fname); 1905 exit(1); 1906 } 1907 if (fwrite(b->p, 1, b->pos, file) != b->pos) { 1908 perror(fname); 1909 exit(1); 1910 } 1911 if (fclose(file) != 0) { 1912 perror(fname); 1913 exit(1); 1914 } 1915 } 1916 1917 static void write_if_changed(struct buffer *b, const char *fname) 1918 { 1919 char *tmp; 1920 FILE *file; 1921 struct stat st; 1922 1923 file = fopen(fname, "r"); 1924 if (!file) 1925 goto write; 1926 1927 if (fstat(fileno(file), &st) < 0) 1928 goto close_write; 1929 1930 if (st.st_size != b->pos) 1931 goto close_write; 1932 1933 tmp = xmalloc(b->pos); 1934 if (fread(tmp, 1, b->pos, file) != b->pos) 1935 goto free_write; 1936 1937 if (memcmp(tmp, b->p, b->pos) != 0) 1938 goto free_write; 1939 1940 free(tmp); 1941 fclose(file); 1942 return; 1943 1944 free_write: 1945 free(tmp); 1946 close_write: 1947 fclose(file); 1948 write: 1949 write_buf(b, fname); 1950 } 1951 1952 static void write_vmlinux_export_c_file(struct module *mod) 1953 { 1954 struct buffer buf = { }; 1955 1956 buf_printf(&buf, 1957 "#include <linux/export-internal.h>\n"); 1958 1959 add_exported_symbols(&buf, mod); 1960 write_if_changed(&buf, ".vmlinux.export.c"); 1961 free(buf.p); 1962 } 1963 1964 /* do sanity checks, and generate *.mod.c file */ 1965 static void write_mod_c_file(struct module *mod) 1966 { 1967 struct buffer buf = { }; 1968 struct module_alias *alias, *next; 1969 char fname[PATH_MAX]; 1970 int ret; 1971 1972 add_header(&buf, mod); 1973 add_exported_symbols(&buf, mod); 1974 add_versions(&buf, mod); 1975 add_depends(&buf, mod); 1976 1977 buf_printf(&buf, "\n"); 1978 list_for_each_entry_safe(alias, next, &mod->aliases, node) { 1979 buf_printf(&buf, "MODULE_ALIAS(\"%s\");\n", alias->str); 1980 list_del(&alias->node); 1981 free(alias); 1982 } 1983 1984 add_srcversion(&buf, mod); 1985 1986 ret = snprintf(fname, sizeof(fname), "%s.mod.c", mod->name); 1987 if (ret >= sizeof(fname)) { 1988 error("%s: too long path was truncated\n", fname); 1989 goto free; 1990 } 1991 1992 write_if_changed(&buf, fname); 1993 1994 free: 1995 free(buf.p); 1996 } 1997 1998 /* parse Module.symvers file. line format: 1999 * 0x12345678<tab>symbol<tab>module<tab>export<tab>namespace 2000 **/ 2001 static void read_dump(const char *fname) 2002 { 2003 char *buf, *pos, *line; 2004 2005 buf = read_text_file(fname); 2006 if (!buf) 2007 /* No symbol versions, silently ignore */ 2008 return; 2009 2010 pos = buf; 2011 2012 while ((line = get_line(&pos))) { 2013 char *symname, *namespace, *modname, *d, *export; 2014 unsigned int crc; 2015 struct module *mod; 2016 struct symbol *s; 2017 bool gpl_only; 2018 2019 if (!(symname = strchr(line, '\t'))) 2020 goto fail; 2021 *symname++ = '\0'; 2022 if (!(modname = strchr(symname, '\t'))) 2023 goto fail; 2024 *modname++ = '\0'; 2025 if (!(export = strchr(modname, '\t'))) 2026 goto fail; 2027 *export++ = '\0'; 2028 if (!(namespace = strchr(export, '\t'))) 2029 goto fail; 2030 *namespace++ = '\0'; 2031 2032 crc = strtoul(line, &d, 16); 2033 if (*symname == '\0' || *modname == '\0' || *d != '\0') 2034 goto fail; 2035 2036 if (!strcmp(export, "EXPORT_SYMBOL_GPL")) { 2037 gpl_only = true; 2038 } else if (!strcmp(export, "EXPORT_SYMBOL")) { 2039 gpl_only = false; 2040 } else { 2041 error("%s: unknown license %s. skip", symname, export); 2042 continue; 2043 } 2044 2045 mod = find_module(modname); 2046 if (!mod) { 2047 mod = new_module(modname, strlen(modname)); 2048 mod->from_dump = true; 2049 } 2050 s = sym_add_exported(symname, mod, gpl_only, namespace); 2051 sym_set_crc(s, crc); 2052 } 2053 free(buf); 2054 return; 2055 fail: 2056 free(buf); 2057 fatal("parse error in symbol dump file\n"); 2058 } 2059 2060 static void write_dump(const char *fname) 2061 { 2062 struct buffer buf = { }; 2063 struct module *mod; 2064 struct symbol *sym; 2065 2066 list_for_each_entry(mod, &modules, list) { 2067 if (mod->from_dump) 2068 continue; 2069 list_for_each_entry(sym, &mod->exported_symbols, list) { 2070 if (trim_unused_exports && !sym->used) 2071 continue; 2072 2073 buf_printf(&buf, "0x%08x\t%s\t%s\tEXPORT_SYMBOL%s\t%s\n", 2074 sym->crc, sym->name, mod->name, 2075 sym->is_gpl_only ? "_GPL" : "", 2076 sym->namespace); 2077 } 2078 } 2079 write_buf(&buf, fname); 2080 free(buf.p); 2081 } 2082 2083 static void write_namespace_deps_files(const char *fname) 2084 { 2085 struct module *mod; 2086 struct namespace_list *ns; 2087 struct buffer ns_deps_buf = {}; 2088 2089 list_for_each_entry(mod, &modules, list) { 2090 2091 if (mod->from_dump || list_empty(&mod->missing_namespaces)) 2092 continue; 2093 2094 buf_printf(&ns_deps_buf, "%s.ko:", mod->name); 2095 2096 list_for_each_entry(ns, &mod->missing_namespaces, list) 2097 buf_printf(&ns_deps_buf, " %s", ns->namespace); 2098 2099 buf_printf(&ns_deps_buf, "\n"); 2100 } 2101 2102 write_if_changed(&ns_deps_buf, fname); 2103 free(ns_deps_buf.p); 2104 } 2105 2106 struct dump_list { 2107 struct list_head list; 2108 const char *file; 2109 }; 2110 2111 static void check_host_endian(void) 2112 { 2113 static const union { 2114 short s; 2115 char c[2]; 2116 } endian_test = { .c = {0x01, 0x02} }; 2117 2118 switch (endian_test.s) { 2119 case 0x0102: 2120 host_is_big_endian = true; 2121 break; 2122 case 0x0201: 2123 host_is_big_endian = false; 2124 break; 2125 default: 2126 fatal("Unknown host endian\n"); 2127 } 2128 } 2129 2130 int main(int argc, char **argv) 2131 { 2132 struct module *mod; 2133 char *missing_namespace_deps = NULL; 2134 char *unused_exports_white_list = NULL; 2135 char *dump_write = NULL, *files_source = NULL; 2136 int opt; 2137 LIST_HEAD(dump_lists); 2138 struct dump_list *dl, *dl2; 2139 2140 while ((opt = getopt(argc, argv, "ei:MmnT:to:au:WwENd:")) != -1) { 2141 switch (opt) { 2142 case 'e': 2143 external_module = true; 2144 break; 2145 case 'i': 2146 dl = xmalloc(sizeof(*dl)); 2147 dl->file = optarg; 2148 list_add_tail(&dl->list, &dump_lists); 2149 break; 2150 case 'M': 2151 module_enabled = true; 2152 break; 2153 case 'm': 2154 modversions = true; 2155 break; 2156 case 'n': 2157 ignore_missing_files = true; 2158 break; 2159 case 'o': 2160 dump_write = optarg; 2161 break; 2162 case 'a': 2163 all_versions = true; 2164 break; 2165 case 'T': 2166 files_source = optarg; 2167 break; 2168 case 't': 2169 trim_unused_exports = true; 2170 break; 2171 case 'u': 2172 unused_exports_white_list = optarg; 2173 break; 2174 case 'W': 2175 extra_warn = true; 2176 break; 2177 case 'w': 2178 warn_unresolved = true; 2179 break; 2180 case 'E': 2181 sec_mismatch_warn_only = false; 2182 break; 2183 case 'N': 2184 allow_missing_ns_imports = true; 2185 break; 2186 case 'd': 2187 missing_namespace_deps = optarg; 2188 break; 2189 default: 2190 exit(1); 2191 } 2192 } 2193 2194 check_host_endian(); 2195 2196 list_for_each_entry_safe(dl, dl2, &dump_lists, list) { 2197 read_dump(dl->file); 2198 list_del(&dl->list); 2199 free(dl); 2200 } 2201 2202 while (optind < argc) 2203 read_symbols(argv[optind++]); 2204 2205 if (files_source) 2206 read_symbols_from_files(files_source); 2207 2208 list_for_each_entry(mod, &modules, list) { 2209 if (mod->from_dump || mod->is_vmlinux) 2210 continue; 2211 2212 check_modname_len(mod); 2213 check_exports(mod); 2214 } 2215 2216 if (unused_exports_white_list) 2217 handle_white_list_exports(unused_exports_white_list); 2218 2219 list_for_each_entry(mod, &modules, list) { 2220 if (mod->from_dump) 2221 continue; 2222 2223 if (mod->is_vmlinux) 2224 write_vmlinux_export_c_file(mod); 2225 else 2226 write_mod_c_file(mod); 2227 } 2228 2229 if (missing_namespace_deps) 2230 write_namespace_deps_files(missing_namespace_deps); 2231 2232 if (dump_write) 2233 write_dump(dump_write); 2234 if (sec_mismatch_count && !sec_mismatch_warn_only) 2235 error("Section mismatches detected.\n" 2236 "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n"); 2237 2238 if (nr_unresolved > MAX_UNRESOLVED_REPORTS) 2239 warn("suppressed %u unresolved symbol warnings because there were too many)\n", 2240 nr_unresolved - MAX_UNRESOLVED_REPORTS); 2241 2242 return error_occurred ? 1 : 0; 2243 } 2244