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 #include "modpost.h" 24 #include "../../include/linux/license.h" 25 26 static bool module_enabled; 27 /* Are we using CONFIG_MODVERSIONS? */ 28 static bool modversions; 29 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ 30 static bool all_versions; 31 /* If we are modposting external module set to 1 */ 32 static bool external_module; 33 /* Only warn about unresolved symbols */ 34 static bool warn_unresolved; 35 36 static int sec_mismatch_count; 37 static bool sec_mismatch_warn_only = true; 38 /* Trim EXPORT_SYMBOLs that are unused by in-tree modules */ 39 static bool trim_unused_exports; 40 41 /* ignore missing files */ 42 static bool ignore_missing_files; 43 /* If set to 1, only warn (instead of error) about missing ns imports */ 44 static bool allow_missing_ns_imports; 45 46 static bool error_occurred; 47 48 static bool extra_warn; 49 50 /* 51 * Cut off the warnings when there are too many. This typically occurs when 52 * vmlinux is missing. ('make modules' without building vmlinux.) 53 */ 54 #define MAX_UNRESOLVED_REPORTS 10 55 static unsigned int nr_unresolved; 56 57 /* In kernel, this size is defined in linux/module.h; 58 * here we use Elf_Addr instead of long for covering cross-compile 59 */ 60 61 #define MODULE_NAME_LEN (64 - sizeof(Elf_Addr)) 62 63 void modpost_log(enum loglevel loglevel, const char *fmt, ...) 64 { 65 va_list arglist; 66 67 switch (loglevel) { 68 case LOG_WARN: 69 fprintf(stderr, "WARNING: "); 70 break; 71 case LOG_ERROR: 72 fprintf(stderr, "ERROR: "); 73 error_occurred = true; 74 break; 75 default: /* invalid loglevel, ignore */ 76 break; 77 } 78 79 fprintf(stderr, "modpost: "); 80 81 va_start(arglist, fmt); 82 vfprintf(stderr, fmt, arglist); 83 va_end(arglist); 84 } 85 86 static inline bool strends(const char *str, const char *postfix) 87 { 88 if (strlen(str) < strlen(postfix)) 89 return false; 90 91 return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0; 92 } 93 94 void *do_nofail(void *ptr, const char *expr) 95 { 96 if (!ptr) 97 fatal("Memory allocation failure: %s.\n", expr); 98 99 return ptr; 100 } 101 102 char *read_text_file(const char *filename) 103 { 104 struct stat st; 105 size_t nbytes; 106 int fd; 107 char *buf; 108 109 fd = open(filename, O_RDONLY); 110 if (fd < 0) { 111 perror(filename); 112 exit(1); 113 } 114 115 if (fstat(fd, &st) < 0) { 116 perror(filename); 117 exit(1); 118 } 119 120 buf = NOFAIL(malloc(st.st_size + 1)); 121 122 nbytes = st.st_size; 123 124 while (nbytes) { 125 ssize_t bytes_read; 126 127 bytes_read = read(fd, buf, nbytes); 128 if (bytes_read < 0) { 129 perror(filename); 130 exit(1); 131 } 132 133 nbytes -= bytes_read; 134 } 135 buf[st.st_size] = '\0'; 136 137 close(fd); 138 139 return buf; 140 } 141 142 char *get_line(char **stringp) 143 { 144 char *orig = *stringp, *next; 145 146 /* do not return the unwanted extra line at EOF */ 147 if (!orig || *orig == '\0') 148 return NULL; 149 150 /* don't use strsep here, it is not available everywhere */ 151 next = strchr(orig, '\n'); 152 if (next) 153 *next++ = '\0'; 154 155 *stringp = next; 156 157 return orig; 158 } 159 160 /* A list of all modules we processed */ 161 LIST_HEAD(modules); 162 163 static struct module *find_module(const char *modname) 164 { 165 struct module *mod; 166 167 list_for_each_entry(mod, &modules, list) { 168 if (strcmp(mod->name, modname) == 0) 169 return mod; 170 } 171 return NULL; 172 } 173 174 static struct module *new_module(const char *name, size_t namelen) 175 { 176 struct module *mod; 177 178 mod = NOFAIL(malloc(sizeof(*mod) + namelen + 1)); 179 memset(mod, 0, sizeof(*mod)); 180 181 INIT_LIST_HEAD(&mod->exported_symbols); 182 INIT_LIST_HEAD(&mod->unresolved_symbols); 183 INIT_LIST_HEAD(&mod->missing_namespaces); 184 INIT_LIST_HEAD(&mod->imported_namespaces); 185 186 memcpy(mod->name, name, namelen); 187 mod->name[namelen] = '\0'; 188 mod->is_vmlinux = (strcmp(mod->name, "vmlinux") == 0); 189 190 /* 191 * Set mod->is_gpl_compatible to true by default. If MODULE_LICENSE() 192 * is missing, do not check the use for EXPORT_SYMBOL_GPL() becasue 193 * modpost will exit wiht error anyway. 194 */ 195 mod->is_gpl_compatible = true; 196 197 list_add_tail(&mod->list, &modules); 198 199 return mod; 200 } 201 202 /* A hash of all exported symbols, 203 * struct symbol is also used for lists of unresolved symbols */ 204 205 #define SYMBOL_HASH_SIZE 1024 206 207 struct symbol { 208 struct symbol *next; 209 struct list_head list; /* link to module::exported_symbols or module::unresolved_symbols */ 210 struct module *module; 211 char *namespace; 212 unsigned int crc; 213 bool crc_valid; 214 bool weak; 215 bool is_func; 216 bool is_gpl_only; /* exported by EXPORT_SYMBOL_GPL */ 217 bool used; /* there exists a user of this symbol */ 218 char name[]; 219 }; 220 221 static struct symbol *symbolhash[SYMBOL_HASH_SIZE]; 222 223 /* This is based on the hash algorithm from gdbm, via tdb */ 224 static inline unsigned int tdb_hash(const char *name) 225 { 226 unsigned value; /* Used to compute the hash value. */ 227 unsigned i; /* Used to cycle through random values. */ 228 229 /* Set the initial value from the key size. */ 230 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++) 231 value = (value + (((unsigned char *)name)[i] << (i*5 % 24))); 232 233 return (1103515243 * value + 12345); 234 } 235 236 /** 237 * Allocate a new symbols for use in the hash of exported symbols or 238 * the list of unresolved symbols per module 239 **/ 240 static struct symbol *alloc_symbol(const char *name) 241 { 242 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1)); 243 244 memset(s, 0, sizeof(*s)); 245 strcpy(s->name, name); 246 247 return s; 248 } 249 250 /* For the hash of exported symbols */ 251 static void hash_add_symbol(struct symbol *sym) 252 { 253 unsigned int hash; 254 255 hash = tdb_hash(sym->name) % SYMBOL_HASH_SIZE; 256 sym->next = symbolhash[hash]; 257 symbolhash[hash] = sym; 258 } 259 260 static void sym_add_unresolved(const char *name, struct module *mod, bool weak) 261 { 262 struct symbol *sym; 263 264 sym = alloc_symbol(name); 265 sym->weak = weak; 266 267 list_add_tail(&sym->list, &mod->unresolved_symbols); 268 } 269 270 static struct symbol *sym_find_with_module(const char *name, struct module *mod) 271 { 272 struct symbol *s; 273 274 /* For our purposes, .foo matches foo. PPC64 needs this. */ 275 if (name[0] == '.') 276 name++; 277 278 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) { 279 if (strcmp(s->name, name) == 0 && (!mod || s->module == mod)) 280 return s; 281 } 282 return NULL; 283 } 284 285 static struct symbol *find_symbol(const char *name) 286 { 287 return sym_find_with_module(name, NULL); 288 } 289 290 struct namespace_list { 291 struct list_head list; 292 char namespace[]; 293 }; 294 295 static bool contains_namespace(struct list_head *head, const char *namespace) 296 { 297 struct namespace_list *list; 298 299 /* 300 * The default namespace is null string "", which is always implicitly 301 * contained. 302 */ 303 if (!namespace[0]) 304 return true; 305 306 list_for_each_entry(list, head, list) { 307 if (!strcmp(list->namespace, namespace)) 308 return true; 309 } 310 311 return false; 312 } 313 314 static void add_namespace(struct list_head *head, const char *namespace) 315 { 316 struct namespace_list *ns_entry; 317 318 if (!contains_namespace(head, namespace)) { 319 ns_entry = NOFAIL(malloc(sizeof(*ns_entry) + 320 strlen(namespace) + 1)); 321 strcpy(ns_entry->namespace, namespace); 322 list_add_tail(&ns_entry->list, head); 323 } 324 } 325 326 static void *sym_get_data_by_offset(const struct elf_info *info, 327 unsigned int secindex, unsigned long offset) 328 { 329 Elf_Shdr *sechdr = &info->sechdrs[secindex]; 330 331 return (void *)info->hdr + sechdr->sh_offset + offset; 332 } 333 334 void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym) 335 { 336 return sym_get_data_by_offset(info, get_secindex(info, sym), 337 sym->st_value); 338 } 339 340 static const char *sech_name(const struct elf_info *info, Elf_Shdr *sechdr) 341 { 342 return sym_get_data_by_offset(info, info->secindex_strings, 343 sechdr->sh_name); 344 } 345 346 static const char *sec_name(const struct elf_info *info, unsigned int secindex) 347 { 348 /* 349 * If sym->st_shndx is a special section index, there is no 350 * corresponding section header. 351 * Return "" if the index is out of range of info->sechdrs[] array. 352 */ 353 if (secindex >= info->num_sections) 354 return ""; 355 356 return sech_name(info, &info->sechdrs[secindex]); 357 } 358 359 #define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0) 360 361 static struct symbol *sym_add_exported(const char *name, struct module *mod, 362 bool gpl_only, const char *namespace) 363 { 364 struct symbol *s = find_symbol(name); 365 366 if (s && (!external_module || s->module->is_vmlinux || s->module == mod)) { 367 error("%s: '%s' exported twice. Previous export was in %s%s\n", 368 mod->name, name, s->module->name, 369 s->module->is_vmlinux ? "" : ".ko"); 370 } 371 372 s = alloc_symbol(name); 373 s->module = mod; 374 s->is_gpl_only = gpl_only; 375 s->namespace = NOFAIL(strdup(namespace)); 376 list_add_tail(&s->list, &mod->exported_symbols); 377 hash_add_symbol(s); 378 379 return s; 380 } 381 382 static void sym_set_crc(struct symbol *sym, unsigned int crc) 383 { 384 sym->crc = crc; 385 sym->crc_valid = true; 386 } 387 388 static void *grab_file(const char *filename, size_t *size) 389 { 390 struct stat st; 391 void *map = MAP_FAILED; 392 int fd; 393 394 fd = open(filename, O_RDONLY); 395 if (fd < 0) 396 return NULL; 397 if (fstat(fd, &st)) 398 goto failed; 399 400 *size = st.st_size; 401 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); 402 403 failed: 404 close(fd); 405 if (map == MAP_FAILED) 406 return NULL; 407 return map; 408 } 409 410 static void release_file(void *file, size_t size) 411 { 412 munmap(file, size); 413 } 414 415 static int parse_elf(struct elf_info *info, const char *filename) 416 { 417 unsigned int i; 418 Elf_Ehdr *hdr; 419 Elf_Shdr *sechdrs; 420 Elf_Sym *sym; 421 const char *secstrings; 422 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U; 423 424 hdr = grab_file(filename, &info->size); 425 if (!hdr) { 426 if (ignore_missing_files) { 427 fprintf(stderr, "%s: %s (ignored)\n", filename, 428 strerror(errno)); 429 return 0; 430 } 431 perror(filename); 432 exit(1); 433 } 434 info->hdr = hdr; 435 if (info->size < sizeof(*hdr)) { 436 /* file too small, assume this is an empty .o file */ 437 return 0; 438 } 439 /* Is this a valid ELF file? */ 440 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) || 441 (hdr->e_ident[EI_MAG1] != ELFMAG1) || 442 (hdr->e_ident[EI_MAG2] != ELFMAG2) || 443 (hdr->e_ident[EI_MAG3] != ELFMAG3)) { 444 /* Not an ELF file - silently ignore it */ 445 return 0; 446 } 447 /* Fix endianness in ELF header */ 448 hdr->e_type = TO_NATIVE(hdr->e_type); 449 hdr->e_machine = TO_NATIVE(hdr->e_machine); 450 hdr->e_version = TO_NATIVE(hdr->e_version); 451 hdr->e_entry = TO_NATIVE(hdr->e_entry); 452 hdr->e_phoff = TO_NATIVE(hdr->e_phoff); 453 hdr->e_shoff = TO_NATIVE(hdr->e_shoff); 454 hdr->e_flags = TO_NATIVE(hdr->e_flags); 455 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize); 456 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize); 457 hdr->e_phnum = TO_NATIVE(hdr->e_phnum); 458 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize); 459 hdr->e_shnum = TO_NATIVE(hdr->e_shnum); 460 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx); 461 sechdrs = (void *)hdr + hdr->e_shoff; 462 info->sechdrs = sechdrs; 463 464 /* modpost only works for relocatable objects */ 465 if (hdr->e_type != ET_REL) 466 fatal("%s: not relocatable object.", filename); 467 468 /* Check if file offset is correct */ 469 if (hdr->e_shoff > info->size) 470 fatal("section header offset=%lu in file '%s' is bigger than filesize=%zu\n", 471 (unsigned long)hdr->e_shoff, filename, info->size); 472 473 if (hdr->e_shnum == SHN_UNDEF) { 474 /* 475 * There are more than 64k sections, 476 * read count from .sh_size. 477 */ 478 info->num_sections = TO_NATIVE(sechdrs[0].sh_size); 479 } 480 else { 481 info->num_sections = hdr->e_shnum; 482 } 483 if (hdr->e_shstrndx == SHN_XINDEX) { 484 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link); 485 } 486 else { 487 info->secindex_strings = hdr->e_shstrndx; 488 } 489 490 /* Fix endianness in section headers */ 491 for (i = 0; i < info->num_sections; i++) { 492 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name); 493 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); 494 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags); 495 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr); 496 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset); 497 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size); 498 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link); 499 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info); 500 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign); 501 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize); 502 } 503 /* Find symbol table. */ 504 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset; 505 for (i = 1; i < info->num_sections; i++) { 506 const char *secname; 507 int nobits = sechdrs[i].sh_type == SHT_NOBITS; 508 509 if (!nobits && sechdrs[i].sh_offset > info->size) 510 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > sizeof(*hrd)=%zu\n", 511 filename, (unsigned long)sechdrs[i].sh_offset, 512 sizeof(*hdr)); 513 514 secname = secstrings + sechdrs[i].sh_name; 515 if (strcmp(secname, ".modinfo") == 0) { 516 if (nobits) 517 fatal("%s has NOBITS .modinfo\n", filename); 518 info->modinfo = (void *)hdr + sechdrs[i].sh_offset; 519 info->modinfo_len = sechdrs[i].sh_size; 520 } else if (!strcmp(secname, ".export_symbol")) { 521 info->export_symbol_secndx = i; 522 } 523 524 if (sechdrs[i].sh_type == SHT_SYMTAB) { 525 unsigned int sh_link_idx; 526 symtab_idx = i; 527 info->symtab_start = (void *)hdr + 528 sechdrs[i].sh_offset; 529 info->symtab_stop = (void *)hdr + 530 sechdrs[i].sh_offset + sechdrs[i].sh_size; 531 sh_link_idx = sechdrs[i].sh_link; 532 info->strtab = (void *)hdr + 533 sechdrs[sh_link_idx].sh_offset; 534 } 535 536 /* 32bit section no. table? ("more than 64k sections") */ 537 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) { 538 symtab_shndx_idx = i; 539 info->symtab_shndx_start = (void *)hdr + 540 sechdrs[i].sh_offset; 541 info->symtab_shndx_stop = (void *)hdr + 542 sechdrs[i].sh_offset + sechdrs[i].sh_size; 543 } 544 } 545 if (!info->symtab_start) 546 fatal("%s has no symtab?\n", filename); 547 548 /* Fix endianness in symbols */ 549 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) { 550 sym->st_shndx = TO_NATIVE(sym->st_shndx); 551 sym->st_name = TO_NATIVE(sym->st_name); 552 sym->st_value = TO_NATIVE(sym->st_value); 553 sym->st_size = TO_NATIVE(sym->st_size); 554 } 555 556 if (symtab_shndx_idx != ~0U) { 557 Elf32_Word *p; 558 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link) 559 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n", 560 filename, sechdrs[symtab_shndx_idx].sh_link, 561 symtab_idx); 562 /* Fix endianness */ 563 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop; 564 p++) 565 *p = TO_NATIVE(*p); 566 } 567 568 symsearch_init(info); 569 570 return 1; 571 } 572 573 static void parse_elf_finish(struct elf_info *info) 574 { 575 symsearch_finish(info); 576 release_file(info->hdr, info->size); 577 } 578 579 static int ignore_undef_symbol(struct elf_info *info, const char *symname) 580 { 581 /* ignore __this_module, it will be resolved shortly */ 582 if (strcmp(symname, "__this_module") == 0) 583 return 1; 584 /* ignore global offset table */ 585 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0) 586 return 1; 587 if (info->hdr->e_machine == EM_PPC) 588 /* Special register function linked on all modules during final link of .ko */ 589 if (strstarts(symname, "_restgpr_") || 590 strstarts(symname, "_savegpr_") || 591 strstarts(symname, "_rest32gpr_") || 592 strstarts(symname, "_save32gpr_") || 593 strstarts(symname, "_restvr_") || 594 strstarts(symname, "_savevr_")) 595 return 1; 596 if (info->hdr->e_machine == EM_PPC64) 597 /* Special register function linked on all modules during final link of .ko */ 598 if (strstarts(symname, "_restgpr0_") || 599 strstarts(symname, "_savegpr0_") || 600 strstarts(symname, "_restvr_") || 601 strstarts(symname, "_savevr_") || 602 strcmp(symname, ".TOC.") == 0) 603 return 1; 604 /* Do not ignore this symbol */ 605 return 0; 606 } 607 608 static void handle_symbol(struct module *mod, struct elf_info *info, 609 const Elf_Sym *sym, const char *symname) 610 { 611 switch (sym->st_shndx) { 612 case SHN_COMMON: 613 if (strstarts(symname, "__gnu_lto_")) { 614 /* Should warn here, but modpost runs before the linker */ 615 } else 616 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name); 617 break; 618 case SHN_UNDEF: 619 /* undefined symbol */ 620 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 621 ELF_ST_BIND(sym->st_info) != STB_WEAK) 622 break; 623 if (ignore_undef_symbol(info, symname)) 624 break; 625 if (info->hdr->e_machine == EM_SPARC || 626 info->hdr->e_machine == EM_SPARCV9) { 627 /* Ignore register directives. */ 628 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER) 629 break; 630 if (symname[0] == '.') { 631 char *munged = NOFAIL(strdup(symname)); 632 munged[0] = '_'; 633 munged[1] = toupper(munged[1]); 634 symname = munged; 635 } 636 } 637 638 sym_add_unresolved(symname, mod, 639 ELF_ST_BIND(sym->st_info) == STB_WEAK); 640 break; 641 default: 642 if (strcmp(symname, "init_module") == 0) 643 mod->has_init = true; 644 if (strcmp(symname, "cleanup_module") == 0) 645 mod->has_cleanup = true; 646 break; 647 } 648 } 649 650 /** 651 * Parse tag=value strings from .modinfo section 652 **/ 653 static char *next_string(char *string, unsigned long *secsize) 654 { 655 /* Skip non-zero chars */ 656 while (string[0]) { 657 string++; 658 if ((*secsize)-- <= 1) 659 return NULL; 660 } 661 662 /* Skip any zero padding. */ 663 while (!string[0]) { 664 string++; 665 if ((*secsize)-- <= 1) 666 return NULL; 667 } 668 return string; 669 } 670 671 static char *get_next_modinfo(struct elf_info *info, const char *tag, 672 char *prev) 673 { 674 char *p; 675 unsigned int taglen = strlen(tag); 676 char *modinfo = info->modinfo; 677 unsigned long size = info->modinfo_len; 678 679 if (prev) { 680 size -= prev - modinfo; 681 modinfo = next_string(prev, &size); 682 } 683 684 for (p = modinfo; p; p = next_string(p, &size)) { 685 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') 686 return p + taglen + 1; 687 } 688 return NULL; 689 } 690 691 static char *get_modinfo(struct elf_info *info, const char *tag) 692 693 { 694 return get_next_modinfo(info, tag, NULL); 695 } 696 697 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) 698 { 699 if (sym) 700 return elf->strtab + sym->st_name; 701 else 702 return "(unknown)"; 703 } 704 705 /* 706 * Check whether the 'string' argument matches one of the 'patterns', 707 * an array of shell wildcard patterns (glob). 708 * 709 * Return true is there is a match. 710 */ 711 static bool match(const char *string, const char *const patterns[]) 712 { 713 const char *pattern; 714 715 while ((pattern = *patterns++)) { 716 if (!fnmatch(pattern, string, 0)) 717 return true; 718 } 719 720 return false; 721 } 722 723 /* useful to pass patterns to match() directly */ 724 #define PATTERNS(...) \ 725 ({ \ 726 static const char *const patterns[] = {__VA_ARGS__, NULL}; \ 727 patterns; \ 728 }) 729 730 /* sections that we do not want to do full section mismatch check on */ 731 static const char *const section_white_list[] = 732 { 733 ".comment*", 734 ".debug*", 735 ".zdebug*", /* Compressed debug sections. */ 736 ".GCC.command.line", /* record-gcc-switches */ 737 ".mdebug*", /* alpha, score, mips etc. */ 738 ".pdr", /* alpha, score, mips etc. */ 739 ".stab*", 740 ".note*", 741 ".got*", 742 ".toc*", 743 ".xt.prop", /* xtensa */ 744 ".xt.lit", /* xtensa */ 745 ".arcextmap*", /* arc */ 746 ".gnu.linkonce.arcext*", /* arc : modules */ 747 ".cmem*", /* EZchip */ 748 ".fmt_slot*", /* EZchip */ 749 ".gnu.lto*", 750 ".discard.*", 751 ".llvm.call-graph-profile", /* call graph */ 752 NULL 753 }; 754 755 /* 756 * This is used to find sections missing the SHF_ALLOC flag. 757 * The cause of this is often a section specified in assembler 758 * without "ax" / "aw". 759 */ 760 static void check_section(const char *modname, struct elf_info *elf, 761 Elf_Shdr *sechdr) 762 { 763 const char *sec = sech_name(elf, sechdr); 764 765 if (sechdr->sh_type == SHT_PROGBITS && 766 !(sechdr->sh_flags & SHF_ALLOC) && 767 !match(sec, section_white_list)) { 768 warn("%s (%s): unexpected non-allocatable section.\n" 769 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n" 770 "Note that for example <linux/init.h> contains\n" 771 "section definitions for use in .S files.\n\n", 772 modname, sec); 773 } 774 } 775 776 777 778 #define ALL_INIT_DATA_SECTIONS \ 779 ".init.setup", ".init.rodata", ".meminit.rodata", \ 780 ".init.data", ".meminit.data" 781 782 #define ALL_PCI_INIT_SECTIONS \ 783 ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \ 784 ".pci_fixup_enable", ".pci_fixup_resume", \ 785 ".pci_fixup_resume_early", ".pci_fixup_suspend" 786 787 #define ALL_XXXINIT_SECTIONS ".meminit.*" 788 789 #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS 790 #define ALL_EXIT_SECTIONS ".exit.*" 791 792 #define DATA_SECTIONS ".data", ".data.rel" 793 #define TEXT_SECTIONS ".text", ".text.*", ".sched.text", \ 794 ".kprobes.text", ".cpuidle.text", ".noinstr.text", \ 795 ".ltext", ".ltext.*" 796 #define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \ 797 ".fixup", ".entry.text", ".exception.text", \ 798 ".coldtext", ".softirqentry.text" 799 800 #define INIT_SECTIONS ".init.*" 801 802 #define ALL_TEXT_SECTIONS ".init.text", ".meminit.text", ".exit.text", \ 803 TEXT_SECTIONS, OTHER_TEXT_SECTIONS 804 805 enum mismatch { 806 TEXTDATA_TO_ANY_INIT_EXIT, 807 XXXINIT_TO_SOME_INIT, 808 ANY_INIT_TO_ANY_EXIT, 809 ANY_EXIT_TO_ANY_INIT, 810 EXTABLE_TO_NON_TEXT, 811 }; 812 813 /** 814 * Describe how to match sections on different criteria: 815 * 816 * @fromsec: Array of sections to be matched. 817 * 818 * @bad_tosec: Relocations applied to a section in @fromsec to a section in 819 * this array is forbidden (black-list). Can be empty. 820 * 821 * @good_tosec: Relocations applied to a section in @fromsec must be 822 * targeting sections in this array (white-list). Can be empty. 823 * 824 * @mismatch: Type of mismatch. 825 */ 826 struct sectioncheck { 827 const char *fromsec[20]; 828 const char *bad_tosec[20]; 829 const char *good_tosec[20]; 830 enum mismatch mismatch; 831 }; 832 833 static const struct sectioncheck sectioncheck[] = { 834 /* Do not reference init/exit code/data from 835 * normal code and data 836 */ 837 { 838 .fromsec = { TEXT_SECTIONS, DATA_SECTIONS, NULL }, 839 .bad_tosec = { ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }, 840 .mismatch = TEXTDATA_TO_ANY_INIT_EXIT, 841 }, 842 /* Do not reference init code/data from meminit code/data */ 843 { 844 .fromsec = { ALL_XXXINIT_SECTIONS, NULL }, 845 .bad_tosec = { INIT_SECTIONS, NULL }, 846 .mismatch = XXXINIT_TO_SOME_INIT, 847 }, 848 /* Do not use exit code/data from init code */ 849 { 850 .fromsec = { ALL_INIT_SECTIONS, NULL }, 851 .bad_tosec = { ALL_EXIT_SECTIONS, NULL }, 852 .mismatch = ANY_INIT_TO_ANY_EXIT, 853 }, 854 /* Do not use init code/data from exit code */ 855 { 856 .fromsec = { ALL_EXIT_SECTIONS, NULL }, 857 .bad_tosec = { ALL_INIT_SECTIONS, NULL }, 858 .mismatch = ANY_EXIT_TO_ANY_INIT, 859 }, 860 { 861 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL }, 862 .bad_tosec = { INIT_SECTIONS, NULL }, 863 .mismatch = ANY_INIT_TO_ANY_EXIT, 864 }, 865 { 866 .fromsec = { "__ex_table", NULL }, 867 /* If you're adding any new black-listed sections in here, consider 868 * adding a special 'printer' for them in scripts/check_extable. 869 */ 870 .bad_tosec = { ".altinstr_replacement", NULL }, 871 .good_tosec = {ALL_TEXT_SECTIONS , NULL}, 872 .mismatch = EXTABLE_TO_NON_TEXT, 873 } 874 }; 875 876 static const struct sectioncheck *section_mismatch( 877 const char *fromsec, const char *tosec) 878 { 879 int i; 880 881 /* 882 * The target section could be the SHT_NUL section when we're 883 * handling relocations to un-resolved symbols, trying to match it 884 * doesn't make much sense and causes build failures on parisc 885 * architectures. 886 */ 887 if (*tosec == '\0') 888 return NULL; 889 890 for (i = 0; i < ARRAY_SIZE(sectioncheck); i++) { 891 const struct sectioncheck *check = §ioncheck[i]; 892 893 if (match(fromsec, check->fromsec)) { 894 if (check->bad_tosec[0] && match(tosec, check->bad_tosec)) 895 return check; 896 if (check->good_tosec[0] && !match(tosec, check->good_tosec)) 897 return check; 898 } 899 } 900 return NULL; 901 } 902 903 /** 904 * Whitelist to allow certain references to pass with no warning. 905 * 906 * Pattern 1: 907 * If a module parameter is declared __initdata and permissions=0 908 * then this is legal despite the warning generated. 909 * We cannot see value of permissions here, so just ignore 910 * this pattern. 911 * The pattern is identified by: 912 * tosec = .init.data 913 * fromsec = .data* 914 * atsym =__param* 915 * 916 * Pattern 1a: 917 * module_param_call() ops can refer to __init set function if permissions=0 918 * The pattern is identified by: 919 * tosec = .init.text 920 * fromsec = .data* 921 * atsym = __param_ops_* 922 * 923 * Pattern 3: 924 * Whitelist all references from .head.text to any init section 925 * 926 * Pattern 4: 927 * Some symbols belong to init section but still it is ok to reference 928 * these from non-init sections as these symbols don't have any memory 929 * allocated for them and symbol address and value are same. So even 930 * if init section is freed, its ok to reference those symbols. 931 * For ex. symbols marking the init section boundaries. 932 * This pattern is identified by 933 * refsymname = __init_begin, _sinittext, _einittext 934 * 935 * Pattern 5: 936 * GCC may optimize static inlines when fed constant arg(s) resulting 937 * in functions like cpumask_empty() -- generating an associated symbol 938 * cpumask_empty.constprop.3 that appears in the audit. If the const that 939 * is passed in comes from __init, like say nmi_ipi_mask, we get a 940 * meaningless section warning. May need to add isra symbols too... 941 * This pattern is identified by 942 * tosec = init section 943 * fromsec = text section 944 * refsymname = *.constprop.* 945 * 946 **/ 947 static int secref_whitelist(const char *fromsec, const char *fromsym, 948 const char *tosec, const char *tosym) 949 { 950 /* Check for pattern 1 */ 951 if (match(tosec, PATTERNS(ALL_INIT_DATA_SECTIONS)) && 952 match(fromsec, PATTERNS(DATA_SECTIONS)) && 953 strstarts(fromsym, "__param")) 954 return 0; 955 956 /* Check for pattern 1a */ 957 if (strcmp(tosec, ".init.text") == 0 && 958 match(fromsec, PATTERNS(DATA_SECTIONS)) && 959 strstarts(fromsym, "__param_ops_")) 960 return 0; 961 962 /* symbols in data sections that may refer to any init/exit sections */ 963 if (match(fromsec, PATTERNS(DATA_SECTIONS)) && 964 match(tosec, PATTERNS(ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS)) && 965 match(fromsym, PATTERNS("*_ops", "*_probe", "*_console"))) 966 return 0; 967 968 /* Check for pattern 3 */ 969 if (strstarts(fromsec, ".head.text") && 970 match(tosec, PATTERNS(ALL_INIT_SECTIONS))) 971 return 0; 972 973 /* Check for pattern 4 */ 974 if (match(tosym, PATTERNS("__init_begin", "_sinittext", "_einittext"))) 975 return 0; 976 977 /* Check for pattern 5 */ 978 if (match(fromsec, PATTERNS(ALL_TEXT_SECTIONS)) && 979 match(tosec, PATTERNS(ALL_INIT_SECTIONS)) && 980 match(fromsym, PATTERNS("*.constprop.*"))) 981 return 0; 982 983 return 1; 984 } 985 986 static Elf_Sym *find_fromsym(struct elf_info *elf, Elf_Addr addr, 987 unsigned int secndx) 988 { 989 return symsearch_find_nearest(elf, addr, secndx, false, ~0); 990 } 991 992 static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym) 993 { 994 Elf_Sym *new_sym; 995 996 /* If the supplied symbol has a valid name, return it */ 997 if (is_valid_name(elf, sym)) 998 return sym; 999 1000 /* 1001 * Strive to find a better symbol name, but the resulting name may not 1002 * match the symbol referenced in the original code. 1003 */ 1004 new_sym = symsearch_find_nearest(elf, addr, get_secindex(elf, sym), 1005 true, 20); 1006 return new_sym ? new_sym : sym; 1007 } 1008 1009 static bool is_executable_section(struct elf_info *elf, unsigned int secndx) 1010 { 1011 if (secndx >= elf->num_sections) 1012 return false; 1013 1014 return (elf->sechdrs[secndx].sh_flags & SHF_EXECINSTR) != 0; 1015 } 1016 1017 static void default_mismatch_handler(const char *modname, struct elf_info *elf, 1018 const struct sectioncheck* const mismatch, 1019 Elf_Sym *tsym, 1020 unsigned int fsecndx, const char *fromsec, Elf_Addr faddr, 1021 const char *tosec, Elf_Addr taddr) 1022 { 1023 Elf_Sym *from; 1024 const char *tosym; 1025 const char *fromsym; 1026 1027 from = find_fromsym(elf, faddr, fsecndx); 1028 fromsym = sym_name(elf, from); 1029 1030 tsym = find_tosym(elf, taddr, tsym); 1031 tosym = sym_name(elf, tsym); 1032 1033 /* check whitelist - we may ignore it */ 1034 if (!secref_whitelist(fromsec, fromsym, tosec, tosym)) 1035 return; 1036 1037 sec_mismatch_count++; 1038 1039 warn("%s: section mismatch in reference: %s+0x%x (section: %s) -> %s (section: %s)\n", 1040 modname, fromsym, 1041 (unsigned int)(faddr - (from ? from->st_value : 0)), 1042 fromsec, tosym, tosec); 1043 1044 if (mismatch->mismatch == EXTABLE_TO_NON_TEXT) { 1045 if (match(tosec, mismatch->bad_tosec)) 1046 fatal("The relocation at %s+0x%lx references\n" 1047 "section \"%s\" which is black-listed.\n" 1048 "Something is seriously wrong and should be fixed.\n" 1049 "You might get more information about where this is\n" 1050 "coming from by using scripts/check_extable.sh %s\n", 1051 fromsec, (long)faddr, tosec, modname); 1052 else if (is_executable_section(elf, get_secindex(elf, tsym))) 1053 warn("The relocation at %s+0x%lx references\n" 1054 "section \"%s\" which is not in the list of\n" 1055 "authorized sections. If you're adding a new section\n" 1056 "and/or if this reference is valid, add \"%s\" to the\n" 1057 "list of authorized sections to jump to on fault.\n" 1058 "This can be achieved by adding \"%s\" to\n" 1059 "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n", 1060 fromsec, (long)faddr, tosec, tosec, tosec); 1061 else 1062 error("%s+0x%lx references non-executable section '%s'\n", 1063 fromsec, (long)faddr, tosec); 1064 } 1065 } 1066 1067 static void check_export_symbol(struct module *mod, struct elf_info *elf, 1068 Elf_Addr faddr, const char *secname, 1069 Elf_Sym *sym) 1070 { 1071 static const char *prefix = "__export_symbol_"; 1072 const char *label_name, *name, *data; 1073 Elf_Sym *label; 1074 struct symbol *s; 1075 bool is_gpl; 1076 1077 label = find_fromsym(elf, faddr, elf->export_symbol_secndx); 1078 label_name = sym_name(elf, label); 1079 1080 if (!strstarts(label_name, prefix)) { 1081 error("%s: .export_symbol section contains strange symbol '%s'\n", 1082 mod->name, label_name); 1083 return; 1084 } 1085 1086 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 1087 ELF_ST_BIND(sym->st_info) != STB_WEAK) { 1088 error("%s: local symbol '%s' was exported\n", mod->name, 1089 label_name + strlen(prefix)); 1090 return; 1091 } 1092 1093 name = sym_name(elf, sym); 1094 if (strcmp(label_name + strlen(prefix), name)) { 1095 error("%s: .export_symbol section references '%s', but it does not seem to be an export symbol\n", 1096 mod->name, name); 1097 return; 1098 } 1099 1100 data = sym_get_data(elf, label); /* license */ 1101 if (!strcmp(data, "GPL")) { 1102 is_gpl = true; 1103 } else if (!strcmp(data, "")) { 1104 is_gpl = false; 1105 } else { 1106 error("%s: unknown license '%s' was specified for '%s'\n", 1107 mod->name, data, name); 1108 return; 1109 } 1110 1111 data += strlen(data) + 1; /* namespace */ 1112 s = sym_add_exported(name, mod, is_gpl, data); 1113 1114 /* 1115 * We need to be aware whether we are exporting a function or 1116 * a data on some architectures. 1117 */ 1118 s->is_func = (ELF_ST_TYPE(sym->st_info) == STT_FUNC); 1119 1120 /* 1121 * For parisc64, symbols prefixed $$ from the library have the symbol type 1122 * STT_LOPROC. They should be handled as functions too. 1123 */ 1124 if (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64 && 1125 elf->hdr->e_machine == EM_PARISC && 1126 ELF_ST_TYPE(sym->st_info) == STT_LOPROC) 1127 s->is_func = true; 1128 1129 if (match(secname, PATTERNS(ALL_INIT_SECTIONS))) 1130 warn("%s: %s: EXPORT_SYMBOL used for init symbol. Remove __init or EXPORT_SYMBOL.\n", 1131 mod->name, name); 1132 else if (match(secname, PATTERNS(ALL_EXIT_SECTIONS))) 1133 warn("%s: %s: EXPORT_SYMBOL used for exit symbol. Remove __exit or EXPORT_SYMBOL.\n", 1134 mod->name, name); 1135 } 1136 1137 static void check_section_mismatch(struct module *mod, struct elf_info *elf, 1138 Elf_Sym *sym, 1139 unsigned int fsecndx, const char *fromsec, 1140 Elf_Addr faddr, Elf_Addr taddr) 1141 { 1142 const char *tosec = sec_name(elf, get_secindex(elf, sym)); 1143 const struct sectioncheck *mismatch; 1144 1145 if (module_enabled && elf->export_symbol_secndx == fsecndx) { 1146 check_export_symbol(mod, elf, faddr, tosec, sym); 1147 return; 1148 } 1149 1150 mismatch = section_mismatch(fromsec, tosec); 1151 if (!mismatch) 1152 return; 1153 1154 default_mismatch_handler(mod->name, elf, mismatch, sym, 1155 fsecndx, fromsec, faddr, 1156 tosec, taddr); 1157 } 1158 1159 static Elf_Addr addend_386_rel(uint32_t *location, unsigned int r_type) 1160 { 1161 switch (r_type) { 1162 case R_386_32: 1163 return TO_NATIVE(*location); 1164 case R_386_PC32: 1165 return TO_NATIVE(*location) + 4; 1166 } 1167 1168 return (Elf_Addr)(-1); 1169 } 1170 1171 static int32_t sign_extend32(int32_t value, int index) 1172 { 1173 uint8_t shift = 31 - index; 1174 1175 return (int32_t)(value << shift) >> shift; 1176 } 1177 1178 static Elf_Addr addend_arm_rel(void *loc, Elf_Sym *sym, unsigned int r_type) 1179 { 1180 uint32_t inst, upper, lower, sign, j1, j2; 1181 int32_t offset; 1182 1183 switch (r_type) { 1184 case R_ARM_ABS32: 1185 case R_ARM_REL32: 1186 inst = TO_NATIVE(*(uint32_t *)loc); 1187 return inst + sym->st_value; 1188 case R_ARM_MOVW_ABS_NC: 1189 case R_ARM_MOVT_ABS: 1190 inst = TO_NATIVE(*(uint32_t *)loc); 1191 offset = sign_extend32(((inst & 0xf0000) >> 4) | (inst & 0xfff), 1192 15); 1193 return offset + sym->st_value; 1194 case R_ARM_PC24: 1195 case R_ARM_CALL: 1196 case R_ARM_JUMP24: 1197 inst = TO_NATIVE(*(uint32_t *)loc); 1198 offset = sign_extend32((inst & 0x00ffffff) << 2, 25); 1199 return offset + sym->st_value + 8; 1200 case R_ARM_THM_MOVW_ABS_NC: 1201 case R_ARM_THM_MOVT_ABS: 1202 upper = TO_NATIVE(*(uint16_t *)loc); 1203 lower = TO_NATIVE(*((uint16_t *)loc + 1)); 1204 offset = sign_extend32(((upper & 0x000f) << 12) | 1205 ((upper & 0x0400) << 1) | 1206 ((lower & 0x7000) >> 4) | 1207 (lower & 0x00ff), 1208 15); 1209 return offset + sym->st_value; 1210 case R_ARM_THM_JUMP19: 1211 /* 1212 * Encoding T3: 1213 * S = upper[10] 1214 * imm6 = upper[5:0] 1215 * J1 = lower[13] 1216 * J2 = lower[11] 1217 * imm11 = lower[10:0] 1218 * imm32 = SignExtend(S:J2:J1:imm6:imm11:'0') 1219 */ 1220 upper = TO_NATIVE(*(uint16_t *)loc); 1221 lower = TO_NATIVE(*((uint16_t *)loc + 1)); 1222 1223 sign = (upper >> 10) & 1; 1224 j1 = (lower >> 13) & 1; 1225 j2 = (lower >> 11) & 1; 1226 offset = sign_extend32((sign << 20) | (j2 << 19) | (j1 << 18) | 1227 ((upper & 0x03f) << 12) | 1228 ((lower & 0x07ff) << 1), 1229 20); 1230 return offset + sym->st_value + 4; 1231 case R_ARM_THM_PC22: 1232 case R_ARM_THM_JUMP24: 1233 /* 1234 * Encoding T4: 1235 * S = upper[10] 1236 * imm10 = upper[9:0] 1237 * J1 = lower[13] 1238 * J2 = lower[11] 1239 * imm11 = lower[10:0] 1240 * I1 = NOT(J1 XOR S) 1241 * I2 = NOT(J2 XOR S) 1242 * imm32 = SignExtend(S:I1:I2:imm10:imm11:'0') 1243 */ 1244 upper = TO_NATIVE(*(uint16_t *)loc); 1245 lower = TO_NATIVE(*((uint16_t *)loc + 1)); 1246 1247 sign = (upper >> 10) & 1; 1248 j1 = (lower >> 13) & 1; 1249 j2 = (lower >> 11) & 1; 1250 offset = sign_extend32((sign << 24) | 1251 ((~(j1 ^ sign) & 1) << 23) | 1252 ((~(j2 ^ sign) & 1) << 22) | 1253 ((upper & 0x03ff) << 12) | 1254 ((lower & 0x07ff) << 1), 1255 24); 1256 return offset + sym->st_value + 4; 1257 } 1258 1259 return (Elf_Addr)(-1); 1260 } 1261 1262 static Elf_Addr addend_mips_rel(uint32_t *location, unsigned int r_type) 1263 { 1264 uint32_t inst; 1265 1266 inst = TO_NATIVE(*location); 1267 switch (r_type) { 1268 case R_MIPS_LO16: 1269 return inst & 0xffff; 1270 case R_MIPS_26: 1271 return (inst & 0x03ffffff) << 2; 1272 case R_MIPS_32: 1273 return inst; 1274 } 1275 return (Elf_Addr)(-1); 1276 } 1277 1278 #ifndef EM_RISCV 1279 #define EM_RISCV 243 1280 #endif 1281 1282 #ifndef R_RISCV_SUB32 1283 #define R_RISCV_SUB32 39 1284 #endif 1285 1286 #ifndef EM_LOONGARCH 1287 #define EM_LOONGARCH 258 1288 #endif 1289 1290 #ifndef R_LARCH_SUB32 1291 #define R_LARCH_SUB32 55 1292 #endif 1293 1294 #ifndef R_LARCH_RELAX 1295 #define R_LARCH_RELAX 100 1296 #endif 1297 1298 #ifndef R_LARCH_ALIGN 1299 #define R_LARCH_ALIGN 102 1300 #endif 1301 1302 static void get_rel_type_and_sym(struct elf_info *elf, uint64_t r_info, 1303 unsigned int *r_type, unsigned int *r_sym) 1304 { 1305 typedef struct { 1306 Elf64_Word r_sym; /* Symbol index */ 1307 unsigned char r_ssym; /* Special symbol for 2nd relocation */ 1308 unsigned char r_type3; /* 3rd relocation type */ 1309 unsigned char r_type2; /* 2nd relocation type */ 1310 unsigned char r_type; /* 1st relocation type */ 1311 } Elf64_Mips_R_Info; 1312 1313 bool is_64bit = (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64); 1314 1315 if (elf->hdr->e_machine == EM_MIPS && is_64bit) { 1316 Elf64_Mips_R_Info *mips64_r_info = (void *)&r_info; 1317 1318 *r_type = mips64_r_info->r_type; 1319 *r_sym = TO_NATIVE(mips64_r_info->r_sym); 1320 return; 1321 } 1322 1323 if (is_64bit) 1324 r_info = TO_NATIVE((Elf64_Xword)r_info); 1325 else 1326 r_info = TO_NATIVE((Elf32_Word)r_info); 1327 1328 *r_type = ELF_R_TYPE(r_info); 1329 *r_sym = ELF_R_SYM(r_info); 1330 } 1331 1332 static void section_rela(struct module *mod, struct elf_info *elf, 1333 unsigned int fsecndx, const char *fromsec, 1334 const Elf_Rela *start, const Elf_Rela *stop) 1335 { 1336 const Elf_Rela *rela; 1337 1338 for (rela = start; rela < stop; rela++) { 1339 Elf_Sym *tsym; 1340 Elf_Addr taddr, r_offset; 1341 unsigned int r_type, r_sym; 1342 1343 r_offset = TO_NATIVE(rela->r_offset); 1344 get_rel_type_and_sym(elf, rela->r_info, &r_type, &r_sym); 1345 1346 tsym = elf->symtab_start + r_sym; 1347 taddr = tsym->st_value + TO_NATIVE(rela->r_addend); 1348 1349 switch (elf->hdr->e_machine) { 1350 case EM_RISCV: 1351 if (!strcmp("__ex_table", fromsec) && 1352 r_type == R_RISCV_SUB32) 1353 continue; 1354 break; 1355 case EM_LOONGARCH: 1356 switch (r_type) { 1357 case R_LARCH_SUB32: 1358 if (!strcmp("__ex_table", fromsec)) 1359 continue; 1360 break; 1361 case R_LARCH_RELAX: 1362 case R_LARCH_ALIGN: 1363 /* These relocs do not refer to symbols */ 1364 continue; 1365 } 1366 break; 1367 } 1368 1369 check_section_mismatch(mod, elf, tsym, 1370 fsecndx, fromsec, r_offset, taddr); 1371 } 1372 } 1373 1374 static void section_rel(struct module *mod, struct elf_info *elf, 1375 unsigned int fsecndx, const char *fromsec, 1376 const Elf_Rel *start, const Elf_Rel *stop) 1377 { 1378 const Elf_Rel *rel; 1379 1380 for (rel = start; rel < stop; rel++) { 1381 Elf_Sym *tsym; 1382 Elf_Addr taddr, r_offset; 1383 unsigned int r_type, r_sym; 1384 void *loc; 1385 1386 r_offset = TO_NATIVE(rel->r_offset); 1387 get_rel_type_and_sym(elf, rel->r_info, &r_type, &r_sym); 1388 1389 loc = sym_get_data_by_offset(elf, fsecndx, r_offset); 1390 tsym = elf->symtab_start + r_sym; 1391 1392 switch (elf->hdr->e_machine) { 1393 case EM_386: 1394 taddr = addend_386_rel(loc, r_type); 1395 break; 1396 case EM_ARM: 1397 taddr = addend_arm_rel(loc, tsym, r_type); 1398 break; 1399 case EM_MIPS: 1400 taddr = addend_mips_rel(loc, r_type); 1401 break; 1402 default: 1403 fatal("Please add code to calculate addend for this architecture\n"); 1404 } 1405 1406 check_section_mismatch(mod, elf, tsym, 1407 fsecndx, fromsec, r_offset, taddr); 1408 } 1409 } 1410 1411 /** 1412 * A module includes a number of sections that are discarded 1413 * either when loaded or when used as built-in. 1414 * For loaded modules all functions marked __init and all data 1415 * marked __initdata will be discarded when the module has been initialized. 1416 * Likewise for modules used built-in the sections marked __exit 1417 * are discarded because __exit marked function are supposed to be called 1418 * only when a module is unloaded which never happens for built-in modules. 1419 * The check_sec_ref() function traverses all relocation records 1420 * to find all references to a section that reference a section that will 1421 * be discarded and warns about it. 1422 **/ 1423 static void check_sec_ref(struct module *mod, struct elf_info *elf) 1424 { 1425 int i; 1426 1427 /* Walk through all sections */ 1428 for (i = 0; i < elf->num_sections; i++) { 1429 Elf_Shdr *sechdr = &elf->sechdrs[i]; 1430 1431 check_section(mod->name, elf, sechdr); 1432 /* We want to process only relocation sections and not .init */ 1433 if (sechdr->sh_type == SHT_REL || sechdr->sh_type == SHT_RELA) { 1434 /* section to which the relocation applies */ 1435 unsigned int secndx = sechdr->sh_info; 1436 const char *secname = sec_name(elf, secndx); 1437 const void *start, *stop; 1438 1439 /* If the section is known good, skip it */ 1440 if (match(secname, section_white_list)) 1441 continue; 1442 1443 start = sym_get_data_by_offset(elf, i, 0); 1444 stop = start + sechdr->sh_size; 1445 1446 if (sechdr->sh_type == SHT_RELA) 1447 section_rela(mod, elf, secndx, secname, 1448 start, stop); 1449 else 1450 section_rel(mod, elf, secndx, secname, 1451 start, stop); 1452 } 1453 } 1454 } 1455 1456 static char *remove_dot(char *s) 1457 { 1458 size_t n = strcspn(s, "."); 1459 1460 if (n && s[n]) { 1461 size_t m = strspn(s + n + 1, "0123456789"); 1462 if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0)) 1463 s[n] = 0; 1464 } 1465 return s; 1466 } 1467 1468 /* 1469 * The CRCs are recorded in .*.cmd files in the form of: 1470 * #SYMVER <name> <crc> 1471 */ 1472 static void extract_crcs_for_object(const char *object, struct module *mod) 1473 { 1474 char cmd_file[PATH_MAX]; 1475 char *buf, *p; 1476 const char *base; 1477 int dirlen, ret; 1478 1479 base = strrchr(object, '/'); 1480 if (base) { 1481 base++; 1482 dirlen = base - object; 1483 } else { 1484 dirlen = 0; 1485 base = object; 1486 } 1487 1488 ret = snprintf(cmd_file, sizeof(cmd_file), "%.*s.%s.cmd", 1489 dirlen, object, base); 1490 if (ret >= sizeof(cmd_file)) { 1491 error("%s: too long path was truncated\n", cmd_file); 1492 return; 1493 } 1494 1495 buf = read_text_file(cmd_file); 1496 p = buf; 1497 1498 while ((p = strstr(p, "\n#SYMVER "))) { 1499 char *name; 1500 size_t namelen; 1501 unsigned int crc; 1502 struct symbol *sym; 1503 1504 name = p + strlen("\n#SYMVER "); 1505 1506 p = strchr(name, ' '); 1507 if (!p) 1508 break; 1509 1510 namelen = p - name; 1511 p++; 1512 1513 if (!isdigit(*p)) 1514 continue; /* skip this line */ 1515 1516 crc = strtoul(p, &p, 0); 1517 if (*p != '\n') 1518 continue; /* skip this line */ 1519 1520 name[namelen] = '\0'; 1521 1522 /* 1523 * sym_find_with_module() may return NULL here. 1524 * It typically occurs when CONFIG_TRIM_UNUSED_KSYMS=y. 1525 * Since commit e1327a127703, genksyms calculates CRCs of all 1526 * symbols, including trimmed ones. Ignore orphan CRCs. 1527 */ 1528 sym = sym_find_with_module(name, mod); 1529 if (sym) 1530 sym_set_crc(sym, crc); 1531 } 1532 1533 free(buf); 1534 } 1535 1536 /* 1537 * The symbol versions (CRC) are recorded in the .*.cmd files. 1538 * Parse them to retrieve CRCs for the current module. 1539 */ 1540 static void mod_set_crcs(struct module *mod) 1541 { 1542 char objlist[PATH_MAX]; 1543 char *buf, *p, *obj; 1544 int ret; 1545 1546 if (mod->is_vmlinux) { 1547 strcpy(objlist, ".vmlinux.objs"); 1548 } else { 1549 /* objects for a module are listed in the *.mod file. */ 1550 ret = snprintf(objlist, sizeof(objlist), "%s.mod", mod->name); 1551 if (ret >= sizeof(objlist)) { 1552 error("%s: too long path was truncated\n", objlist); 1553 return; 1554 } 1555 } 1556 1557 buf = read_text_file(objlist); 1558 p = buf; 1559 1560 while ((obj = strsep(&p, "\n")) && obj[0]) 1561 extract_crcs_for_object(obj, mod); 1562 1563 free(buf); 1564 } 1565 1566 static void read_symbols(const char *modname) 1567 { 1568 const char *symname; 1569 char *version; 1570 char *license; 1571 char *namespace; 1572 struct module *mod; 1573 struct elf_info info = { }; 1574 Elf_Sym *sym; 1575 1576 if (!parse_elf(&info, modname)) 1577 return; 1578 1579 if (!strends(modname, ".o")) { 1580 error("%s: filename must be suffixed with .o\n", modname); 1581 return; 1582 } 1583 1584 /* strip trailing .o */ 1585 mod = new_module(modname, strlen(modname) - strlen(".o")); 1586 1587 if (!mod->is_vmlinux) { 1588 license = get_modinfo(&info, "license"); 1589 if (!license) 1590 error("missing MODULE_LICENSE() in %s\n", modname); 1591 while (license) { 1592 if (!license_is_gpl_compatible(license)) { 1593 mod->is_gpl_compatible = false; 1594 break; 1595 } 1596 license = get_next_modinfo(&info, "license", license); 1597 } 1598 1599 namespace = get_modinfo(&info, "import_ns"); 1600 while (namespace) { 1601 add_namespace(&mod->imported_namespaces, namespace); 1602 namespace = get_next_modinfo(&info, "import_ns", 1603 namespace); 1604 } 1605 1606 if (extra_warn && !get_modinfo(&info, "description")) 1607 warn("missing MODULE_DESCRIPTION() in %s\n", modname); 1608 } 1609 1610 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { 1611 symname = remove_dot(info.strtab + sym->st_name); 1612 1613 handle_symbol(mod, &info, sym, symname); 1614 handle_moddevtable(mod, &info, sym, symname); 1615 } 1616 1617 check_sec_ref(mod, &info); 1618 1619 if (!mod->is_vmlinux) { 1620 version = get_modinfo(&info, "version"); 1621 if (version || all_versions) 1622 get_src_version(mod->name, mod->srcversion, 1623 sizeof(mod->srcversion) - 1); 1624 } 1625 1626 parse_elf_finish(&info); 1627 1628 if (modversions) { 1629 /* 1630 * Our trick to get versioning for module struct etc. - it's 1631 * never passed as an argument to an exported function, so 1632 * the automatic versioning doesn't pick it up, but it's really 1633 * important anyhow. 1634 */ 1635 sym_add_unresolved("module_layout", mod, false); 1636 1637 mod_set_crcs(mod); 1638 } 1639 } 1640 1641 static void read_symbols_from_files(const char *filename) 1642 { 1643 FILE *in = stdin; 1644 char fname[PATH_MAX]; 1645 1646 in = fopen(filename, "r"); 1647 if (!in) 1648 fatal("Can't open filenames file %s: %m", filename); 1649 1650 while (fgets(fname, PATH_MAX, in) != NULL) { 1651 if (strends(fname, "\n")) 1652 fname[strlen(fname)-1] = '\0'; 1653 read_symbols(fname); 1654 } 1655 1656 fclose(in); 1657 } 1658 1659 #define SZ 500 1660 1661 /* We first write the generated file into memory using the 1662 * following helper, then compare to the file on disk and 1663 * only update the later if anything changed */ 1664 1665 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf, 1666 const char *fmt, ...) 1667 { 1668 char tmp[SZ]; 1669 int len; 1670 va_list ap; 1671 1672 va_start(ap, fmt); 1673 len = vsnprintf(tmp, SZ, fmt, ap); 1674 buf_write(buf, tmp, len); 1675 va_end(ap); 1676 } 1677 1678 void buf_write(struct buffer *buf, const char *s, int len) 1679 { 1680 if (buf->size - buf->pos < len) { 1681 buf->size += len + SZ; 1682 buf->p = NOFAIL(realloc(buf->p, buf->size)); 1683 } 1684 strncpy(buf->p + buf->pos, s, len); 1685 buf->pos += len; 1686 } 1687 1688 static void check_exports(struct module *mod) 1689 { 1690 struct symbol *s, *exp; 1691 1692 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1693 const char *basename; 1694 exp = find_symbol(s->name); 1695 if (!exp) { 1696 if (!s->weak && nr_unresolved++ < MAX_UNRESOLVED_REPORTS) 1697 modpost_log(warn_unresolved ? LOG_WARN : LOG_ERROR, 1698 "\"%s\" [%s.ko] undefined!\n", 1699 s->name, mod->name); 1700 continue; 1701 } 1702 if (exp->module == mod) { 1703 error("\"%s\" [%s.ko] was exported without definition\n", 1704 s->name, mod->name); 1705 continue; 1706 } 1707 1708 exp->used = true; 1709 s->module = exp->module; 1710 s->crc_valid = exp->crc_valid; 1711 s->crc = exp->crc; 1712 1713 basename = strrchr(mod->name, '/'); 1714 if (basename) 1715 basename++; 1716 else 1717 basename = mod->name; 1718 1719 if (!contains_namespace(&mod->imported_namespaces, exp->namespace)) { 1720 modpost_log(allow_missing_ns_imports ? LOG_WARN : LOG_ERROR, 1721 "module %s uses symbol %s from namespace %s, but does not import it.\n", 1722 basename, exp->name, exp->namespace); 1723 add_namespace(&mod->missing_namespaces, exp->namespace); 1724 } 1725 1726 if (!mod->is_gpl_compatible && exp->is_gpl_only) 1727 error("GPL-incompatible module %s.ko uses GPL-only symbol '%s'\n", 1728 basename, exp->name); 1729 } 1730 } 1731 1732 static void handle_white_list_exports(const char *white_list) 1733 { 1734 char *buf, *p, *name; 1735 1736 buf = read_text_file(white_list); 1737 p = buf; 1738 1739 while ((name = strsep(&p, "\n"))) { 1740 struct symbol *sym = find_symbol(name); 1741 1742 if (sym) 1743 sym->used = true; 1744 } 1745 1746 free(buf); 1747 } 1748 1749 static void check_modname_len(struct module *mod) 1750 { 1751 const char *mod_name; 1752 1753 mod_name = strrchr(mod->name, '/'); 1754 if (mod_name == NULL) 1755 mod_name = mod->name; 1756 else 1757 mod_name++; 1758 if (strlen(mod_name) >= MODULE_NAME_LEN) 1759 error("module name is too long [%s.ko]\n", mod->name); 1760 } 1761 1762 /** 1763 * Header for the generated file 1764 **/ 1765 static void add_header(struct buffer *b, struct module *mod) 1766 { 1767 buf_printf(b, "#include <linux/module.h>\n"); 1768 /* 1769 * Include build-salt.h after module.h in order to 1770 * inherit the definitions. 1771 */ 1772 buf_printf(b, "#define INCLUDE_VERMAGIC\n"); 1773 buf_printf(b, "#include <linux/build-salt.h>\n"); 1774 buf_printf(b, "#include <linux/elfnote-lto.h>\n"); 1775 buf_printf(b, "#include <linux/export-internal.h>\n"); 1776 buf_printf(b, "#include <linux/vermagic.h>\n"); 1777 buf_printf(b, "#include <linux/compiler.h>\n"); 1778 buf_printf(b, "\n"); 1779 buf_printf(b, "#ifdef CONFIG_UNWINDER_ORC\n"); 1780 buf_printf(b, "#include <asm/orc_header.h>\n"); 1781 buf_printf(b, "ORC_HEADER;\n"); 1782 buf_printf(b, "#endif\n"); 1783 buf_printf(b, "\n"); 1784 buf_printf(b, "BUILD_SALT;\n"); 1785 buf_printf(b, "BUILD_LTO_INFO;\n"); 1786 buf_printf(b, "\n"); 1787 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n"); 1788 buf_printf(b, "MODULE_INFO(name, KBUILD_MODNAME);\n"); 1789 buf_printf(b, "\n"); 1790 buf_printf(b, "__visible struct module __this_module\n"); 1791 buf_printf(b, "__section(\".gnu.linkonce.this_module\") = {\n"); 1792 buf_printf(b, "\t.name = KBUILD_MODNAME,\n"); 1793 if (mod->has_init) 1794 buf_printf(b, "\t.init = init_module,\n"); 1795 if (mod->has_cleanup) 1796 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n" 1797 "\t.exit = cleanup_module,\n" 1798 "#endif\n"); 1799 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n"); 1800 buf_printf(b, "};\n"); 1801 1802 if (!external_module) 1803 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n"); 1804 1805 buf_printf(b, 1806 "\n" 1807 "#ifdef CONFIG_MITIGATION_RETPOLINE\n" 1808 "MODULE_INFO(retpoline, \"Y\");\n" 1809 "#endif\n"); 1810 1811 if (strstarts(mod->name, "drivers/staging")) 1812 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); 1813 1814 if (strstarts(mod->name, "tools/testing")) 1815 buf_printf(b, "\nMODULE_INFO(test, \"Y\");\n"); 1816 } 1817 1818 static void add_exported_symbols(struct buffer *buf, struct module *mod) 1819 { 1820 struct symbol *sym; 1821 1822 /* generate struct for exported symbols */ 1823 buf_printf(buf, "\n"); 1824 list_for_each_entry(sym, &mod->exported_symbols, list) { 1825 if (trim_unused_exports && !sym->used) 1826 continue; 1827 1828 buf_printf(buf, "KSYMTAB_%s(%s, \"%s\", \"%s\");\n", 1829 sym->is_func ? "FUNC" : "DATA", sym->name, 1830 sym->is_gpl_only ? "_gpl" : "", sym->namespace); 1831 } 1832 1833 if (!modversions) 1834 return; 1835 1836 /* record CRCs for exported symbols */ 1837 buf_printf(buf, "\n"); 1838 list_for_each_entry(sym, &mod->exported_symbols, list) { 1839 if (trim_unused_exports && !sym->used) 1840 continue; 1841 1842 if (!sym->crc_valid) 1843 warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n" 1844 "Is \"%s\" prototyped in <asm/asm-prototypes.h>?\n", 1845 sym->name, mod->name, mod->is_vmlinux ? "" : ".ko", 1846 sym->name); 1847 1848 buf_printf(buf, "SYMBOL_CRC(%s, 0x%08x, \"%s\");\n", 1849 sym->name, sym->crc, sym->is_gpl_only ? "_gpl" : ""); 1850 } 1851 } 1852 1853 /** 1854 * Record CRCs for unresolved symbols 1855 **/ 1856 static void add_versions(struct buffer *b, struct module *mod) 1857 { 1858 struct symbol *s; 1859 1860 if (!modversions) 1861 return; 1862 1863 buf_printf(b, "\n"); 1864 buf_printf(b, "static const struct modversion_info ____versions[]\n"); 1865 buf_printf(b, "__used __section(\"__versions\") = {\n"); 1866 1867 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1868 if (!s->module) 1869 continue; 1870 if (!s->crc_valid) { 1871 warn("\"%s\" [%s.ko] has no CRC!\n", 1872 s->name, mod->name); 1873 continue; 1874 } 1875 if (strlen(s->name) >= MODULE_NAME_LEN) { 1876 error("too long symbol \"%s\" [%s.ko]\n", 1877 s->name, mod->name); 1878 break; 1879 } 1880 buf_printf(b, "\t{ %#8x, \"%s\" },\n", 1881 s->crc, s->name); 1882 } 1883 1884 buf_printf(b, "};\n"); 1885 } 1886 1887 static void add_depends(struct buffer *b, struct module *mod) 1888 { 1889 struct symbol *s; 1890 int first = 1; 1891 1892 /* Clear ->seen flag of modules that own symbols needed by this. */ 1893 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1894 if (s->module) 1895 s->module->seen = s->module->is_vmlinux; 1896 } 1897 1898 buf_printf(b, "\n"); 1899 buf_printf(b, "MODULE_INFO(depends, \""); 1900 list_for_each_entry(s, &mod->unresolved_symbols, list) { 1901 const char *p; 1902 if (!s->module) 1903 continue; 1904 1905 if (s->module->seen) 1906 continue; 1907 1908 s->module->seen = true; 1909 p = strrchr(s->module->name, '/'); 1910 if (p) 1911 p++; 1912 else 1913 p = s->module->name; 1914 buf_printf(b, "%s%s", first ? "" : ",", p); 1915 first = 0; 1916 } 1917 buf_printf(b, "\");\n"); 1918 } 1919 1920 static void add_srcversion(struct buffer *b, struct module *mod) 1921 { 1922 if (mod->srcversion[0]) { 1923 buf_printf(b, "\n"); 1924 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n", 1925 mod->srcversion); 1926 } 1927 } 1928 1929 static void write_buf(struct buffer *b, const char *fname) 1930 { 1931 FILE *file; 1932 1933 if (error_occurred) 1934 return; 1935 1936 file = fopen(fname, "w"); 1937 if (!file) { 1938 perror(fname); 1939 exit(1); 1940 } 1941 if (fwrite(b->p, 1, b->pos, file) != b->pos) { 1942 perror(fname); 1943 exit(1); 1944 } 1945 if (fclose(file) != 0) { 1946 perror(fname); 1947 exit(1); 1948 } 1949 } 1950 1951 static void write_if_changed(struct buffer *b, const char *fname) 1952 { 1953 char *tmp; 1954 FILE *file; 1955 struct stat st; 1956 1957 file = fopen(fname, "r"); 1958 if (!file) 1959 goto write; 1960 1961 if (fstat(fileno(file), &st) < 0) 1962 goto close_write; 1963 1964 if (st.st_size != b->pos) 1965 goto close_write; 1966 1967 tmp = NOFAIL(malloc(b->pos)); 1968 if (fread(tmp, 1, b->pos, file) != b->pos) 1969 goto free_write; 1970 1971 if (memcmp(tmp, b->p, b->pos) != 0) 1972 goto free_write; 1973 1974 free(tmp); 1975 fclose(file); 1976 return; 1977 1978 free_write: 1979 free(tmp); 1980 close_write: 1981 fclose(file); 1982 write: 1983 write_buf(b, fname); 1984 } 1985 1986 static void write_vmlinux_export_c_file(struct module *mod) 1987 { 1988 struct buffer buf = { }; 1989 1990 buf_printf(&buf, 1991 "#include <linux/export-internal.h>\n"); 1992 1993 add_exported_symbols(&buf, mod); 1994 write_if_changed(&buf, ".vmlinux.export.c"); 1995 free(buf.p); 1996 } 1997 1998 /* do sanity checks, and generate *.mod.c file */ 1999 static void write_mod_c_file(struct module *mod) 2000 { 2001 struct buffer buf = { }; 2002 char fname[PATH_MAX]; 2003 int ret; 2004 2005 add_header(&buf, mod); 2006 add_exported_symbols(&buf, mod); 2007 add_versions(&buf, mod); 2008 add_depends(&buf, mod); 2009 add_moddevtable(&buf, mod); 2010 add_srcversion(&buf, mod); 2011 2012 ret = snprintf(fname, sizeof(fname), "%s.mod.c", mod->name); 2013 if (ret >= sizeof(fname)) { 2014 error("%s: too long path was truncated\n", fname); 2015 goto free; 2016 } 2017 2018 write_if_changed(&buf, fname); 2019 2020 free: 2021 free(buf.p); 2022 } 2023 2024 /* parse Module.symvers file. line format: 2025 * 0x12345678<tab>symbol<tab>module<tab>export<tab>namespace 2026 **/ 2027 static void read_dump(const char *fname) 2028 { 2029 char *buf, *pos, *line; 2030 2031 buf = read_text_file(fname); 2032 if (!buf) 2033 /* No symbol versions, silently ignore */ 2034 return; 2035 2036 pos = buf; 2037 2038 while ((line = get_line(&pos))) { 2039 char *symname, *namespace, *modname, *d, *export; 2040 unsigned int crc; 2041 struct module *mod; 2042 struct symbol *s; 2043 bool gpl_only; 2044 2045 if (!(symname = strchr(line, '\t'))) 2046 goto fail; 2047 *symname++ = '\0'; 2048 if (!(modname = strchr(symname, '\t'))) 2049 goto fail; 2050 *modname++ = '\0'; 2051 if (!(export = strchr(modname, '\t'))) 2052 goto fail; 2053 *export++ = '\0'; 2054 if (!(namespace = strchr(export, '\t'))) 2055 goto fail; 2056 *namespace++ = '\0'; 2057 2058 crc = strtoul(line, &d, 16); 2059 if (*symname == '\0' || *modname == '\0' || *d != '\0') 2060 goto fail; 2061 2062 if (!strcmp(export, "EXPORT_SYMBOL_GPL")) { 2063 gpl_only = true; 2064 } else if (!strcmp(export, "EXPORT_SYMBOL")) { 2065 gpl_only = false; 2066 } else { 2067 error("%s: unknown license %s. skip", symname, export); 2068 continue; 2069 } 2070 2071 mod = find_module(modname); 2072 if (!mod) { 2073 mod = new_module(modname, strlen(modname)); 2074 mod->from_dump = true; 2075 } 2076 s = sym_add_exported(symname, mod, gpl_only, namespace); 2077 sym_set_crc(s, crc); 2078 } 2079 free(buf); 2080 return; 2081 fail: 2082 free(buf); 2083 fatal("parse error in symbol dump file\n"); 2084 } 2085 2086 static void write_dump(const char *fname) 2087 { 2088 struct buffer buf = { }; 2089 struct module *mod; 2090 struct symbol *sym; 2091 2092 list_for_each_entry(mod, &modules, list) { 2093 if (mod->from_dump) 2094 continue; 2095 list_for_each_entry(sym, &mod->exported_symbols, list) { 2096 if (trim_unused_exports && !sym->used) 2097 continue; 2098 2099 buf_printf(&buf, "0x%08x\t%s\t%s\tEXPORT_SYMBOL%s\t%s\n", 2100 sym->crc, sym->name, mod->name, 2101 sym->is_gpl_only ? "_GPL" : "", 2102 sym->namespace); 2103 } 2104 } 2105 write_buf(&buf, fname); 2106 free(buf.p); 2107 } 2108 2109 static void write_namespace_deps_files(const char *fname) 2110 { 2111 struct module *mod; 2112 struct namespace_list *ns; 2113 struct buffer ns_deps_buf = {}; 2114 2115 list_for_each_entry(mod, &modules, list) { 2116 2117 if (mod->from_dump || list_empty(&mod->missing_namespaces)) 2118 continue; 2119 2120 buf_printf(&ns_deps_buf, "%s.ko:", mod->name); 2121 2122 list_for_each_entry(ns, &mod->missing_namespaces, list) 2123 buf_printf(&ns_deps_buf, " %s", ns->namespace); 2124 2125 buf_printf(&ns_deps_buf, "\n"); 2126 } 2127 2128 write_if_changed(&ns_deps_buf, fname); 2129 free(ns_deps_buf.p); 2130 } 2131 2132 struct dump_list { 2133 struct list_head list; 2134 const char *file; 2135 }; 2136 2137 int main(int argc, char **argv) 2138 { 2139 struct module *mod; 2140 char *missing_namespace_deps = NULL; 2141 char *unused_exports_white_list = NULL; 2142 char *dump_write = NULL, *files_source = NULL; 2143 int opt; 2144 LIST_HEAD(dump_lists); 2145 struct dump_list *dl, *dl2; 2146 2147 while ((opt = getopt(argc, argv, "ei:MmnT:to:au:WwENd:")) != -1) { 2148 switch (opt) { 2149 case 'e': 2150 external_module = true; 2151 break; 2152 case 'i': 2153 dl = NOFAIL(malloc(sizeof(*dl))); 2154 dl->file = optarg; 2155 list_add_tail(&dl->list, &dump_lists); 2156 break; 2157 case 'M': 2158 module_enabled = true; 2159 break; 2160 case 'm': 2161 modversions = true; 2162 break; 2163 case 'n': 2164 ignore_missing_files = true; 2165 break; 2166 case 'o': 2167 dump_write = optarg; 2168 break; 2169 case 'a': 2170 all_versions = true; 2171 break; 2172 case 'T': 2173 files_source = optarg; 2174 break; 2175 case 't': 2176 trim_unused_exports = true; 2177 break; 2178 case 'u': 2179 unused_exports_white_list = optarg; 2180 break; 2181 case 'W': 2182 extra_warn = true; 2183 break; 2184 case 'w': 2185 warn_unresolved = true; 2186 break; 2187 case 'E': 2188 sec_mismatch_warn_only = false; 2189 break; 2190 case 'N': 2191 allow_missing_ns_imports = true; 2192 break; 2193 case 'd': 2194 missing_namespace_deps = optarg; 2195 break; 2196 default: 2197 exit(1); 2198 } 2199 } 2200 2201 list_for_each_entry_safe(dl, dl2, &dump_lists, list) { 2202 read_dump(dl->file); 2203 list_del(&dl->list); 2204 free(dl); 2205 } 2206 2207 while (optind < argc) 2208 read_symbols(argv[optind++]); 2209 2210 if (files_source) 2211 read_symbols_from_files(files_source); 2212 2213 list_for_each_entry(mod, &modules, list) { 2214 if (mod->from_dump || mod->is_vmlinux) 2215 continue; 2216 2217 check_modname_len(mod); 2218 check_exports(mod); 2219 } 2220 2221 if (unused_exports_white_list) 2222 handle_white_list_exports(unused_exports_white_list); 2223 2224 list_for_each_entry(mod, &modules, list) { 2225 if (mod->from_dump) 2226 continue; 2227 2228 if (mod->is_vmlinux) 2229 write_vmlinux_export_c_file(mod); 2230 else 2231 write_mod_c_file(mod); 2232 } 2233 2234 if (missing_namespace_deps) 2235 write_namespace_deps_files(missing_namespace_deps); 2236 2237 if (dump_write) 2238 write_dump(dump_write); 2239 if (sec_mismatch_count && !sec_mismatch_warn_only) 2240 error("Section mismatches detected.\n" 2241 "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n"); 2242 2243 if (nr_unresolved > MAX_UNRESOLVED_REPORTS) 2244 warn("suppressed %u unresolved symbol warnings because there were too many)\n", 2245 nr_unresolved - MAX_UNRESOLVED_REPORTS); 2246 2247 return error_occurred ? 1 : 0; 2248 } 2249