1 /* Postprocess module symbol versions 2 * 3 * Copyright 2003 Kai Germaschewski 4 * Copyright 2002-2004 Rusty Russell, IBM Corporation 5 * Copyright 2006-2008 Sam Ravnborg 6 * Based in part on module-init-tools/depmod.c,file2alias 7 * 8 * This software may be used and distributed according to the terms 9 * of the GNU General Public License, incorporated herein by reference. 10 * 11 * Usage: modpost vmlinux module1.o module2.o ... 12 */ 13 14 #define _GNU_SOURCE 15 #include <stdio.h> 16 #include <ctype.h> 17 #include <string.h> 18 #include "modpost.h" 19 #include "../../include/generated/autoconf.h" 20 #include "../../include/linux/license.h" 21 22 /* Some toolchains use a `_' prefix for all user symbols. */ 23 #ifdef CONFIG_SYMBOL_PREFIX 24 #define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX 25 #else 26 #define MODULE_SYMBOL_PREFIX "" 27 #endif 28 29 30 /* Are we using CONFIG_MODVERSIONS? */ 31 int modversions = 0; 32 /* Warn about undefined symbols? (do so if we have vmlinux) */ 33 int have_vmlinux = 0; 34 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ 35 static int all_versions = 0; 36 /* If we are modposting external module set to 1 */ 37 static int external_module = 0; 38 /* Warn about section mismatch in vmlinux if set to 1 */ 39 static int vmlinux_section_warnings = 1; 40 /* Only warn about unresolved symbols */ 41 static int warn_unresolved = 0; 42 /* How a symbol is exported */ 43 static int sec_mismatch_count = 0; 44 static int sec_mismatch_verbose = 1; 45 46 enum export { 47 export_plain, export_unused, export_gpl, 48 export_unused_gpl, export_gpl_future, export_unknown 49 }; 50 51 #define PRINTF __attribute__ ((format (printf, 1, 2))) 52 53 PRINTF void fatal(const char *fmt, ...) 54 { 55 va_list arglist; 56 57 fprintf(stderr, "FATAL: "); 58 59 va_start(arglist, fmt); 60 vfprintf(stderr, fmt, arglist); 61 va_end(arglist); 62 63 exit(1); 64 } 65 66 PRINTF void warn(const char *fmt, ...) 67 { 68 va_list arglist; 69 70 fprintf(stderr, "WARNING: "); 71 72 va_start(arglist, fmt); 73 vfprintf(stderr, fmt, arglist); 74 va_end(arglist); 75 } 76 77 PRINTF void merror(const char *fmt, ...) 78 { 79 va_list arglist; 80 81 fprintf(stderr, "ERROR: "); 82 83 va_start(arglist, fmt); 84 vfprintf(stderr, fmt, arglist); 85 va_end(arglist); 86 } 87 88 static int is_vmlinux(const char *modname) 89 { 90 const char *myname; 91 92 myname = strrchr(modname, '/'); 93 if (myname) 94 myname++; 95 else 96 myname = modname; 97 98 return (strcmp(myname, "vmlinux") == 0) || 99 (strcmp(myname, "vmlinux.o") == 0); 100 } 101 102 void *do_nofail(void *ptr, const char *expr) 103 { 104 if (!ptr) 105 fatal("modpost: Memory allocation failure: %s.\n", expr); 106 107 return ptr; 108 } 109 110 /* A list of all modules we processed */ 111 static struct module *modules; 112 113 static struct module *find_module(char *modname) 114 { 115 struct module *mod; 116 117 for (mod = modules; mod; mod = mod->next) 118 if (strcmp(mod->name, modname) == 0) 119 break; 120 return mod; 121 } 122 123 static struct module *new_module(char *modname) 124 { 125 struct module *mod; 126 char *p, *s; 127 128 mod = NOFAIL(malloc(sizeof(*mod))); 129 memset(mod, 0, sizeof(*mod)); 130 p = NOFAIL(strdup(modname)); 131 132 /* strip trailing .o */ 133 s = strrchr(p, '.'); 134 if (s != NULL) 135 if (strcmp(s, ".o") == 0) 136 *s = '\0'; 137 138 /* add to list */ 139 mod->name = p; 140 mod->gpl_compatible = -1; 141 mod->next = modules; 142 modules = mod; 143 144 return mod; 145 } 146 147 /* A hash of all exported symbols, 148 * struct symbol is also used for lists of unresolved symbols */ 149 150 #define SYMBOL_HASH_SIZE 1024 151 152 struct symbol { 153 struct symbol *next; 154 struct module *module; 155 unsigned int crc; 156 int crc_valid; 157 unsigned int weak:1; 158 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */ 159 unsigned int kernel:1; /* 1 if symbol is from kernel 160 * (only for external modules) **/ 161 unsigned int preloaded:1; /* 1 if symbol from Module.symvers */ 162 enum export export; /* Type of export */ 163 char name[0]; 164 }; 165 166 static struct symbol *symbolhash[SYMBOL_HASH_SIZE]; 167 168 /* This is based on the hash agorithm from gdbm, via tdb */ 169 static inline unsigned int tdb_hash(const char *name) 170 { 171 unsigned value; /* Used to compute the hash value. */ 172 unsigned i; /* Used to cycle through random values. */ 173 174 /* Set the initial value from the key size. */ 175 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++) 176 value = (value + (((unsigned char *)name)[i] << (i*5 % 24))); 177 178 return (1103515243 * value + 12345); 179 } 180 181 /** 182 * Allocate a new symbols for use in the hash of exported symbols or 183 * the list of unresolved symbols per module 184 **/ 185 static struct symbol *alloc_symbol(const char *name, unsigned int weak, 186 struct symbol *next) 187 { 188 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1)); 189 190 memset(s, 0, sizeof(*s)); 191 strcpy(s->name, name); 192 s->weak = weak; 193 s->next = next; 194 return s; 195 } 196 197 /* For the hash of exported symbols */ 198 static struct symbol *new_symbol(const char *name, struct module *module, 199 enum export export) 200 { 201 unsigned int hash; 202 struct symbol *new; 203 204 hash = tdb_hash(name) % SYMBOL_HASH_SIZE; 205 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]); 206 new->module = module; 207 new->export = export; 208 return new; 209 } 210 211 static struct symbol *find_symbol(const char *name) 212 { 213 struct symbol *s; 214 215 /* For our purposes, .foo matches foo. PPC64 needs this. */ 216 if (name[0] == '.') 217 name++; 218 219 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) { 220 if (strcmp(s->name, name) == 0) 221 return s; 222 } 223 return NULL; 224 } 225 226 static struct { 227 const char *str; 228 enum export export; 229 } export_list[] = { 230 { .str = "EXPORT_SYMBOL", .export = export_plain }, 231 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused }, 232 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl }, 233 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl }, 234 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future }, 235 { .str = "(unknown)", .export = export_unknown }, 236 }; 237 238 239 static const char *export_str(enum export ex) 240 { 241 return export_list[ex].str; 242 } 243 244 static enum export export_no(const char *s) 245 { 246 int i; 247 248 if (!s) 249 return export_unknown; 250 for (i = 0; export_list[i].export != export_unknown; i++) { 251 if (strcmp(export_list[i].str, s) == 0) 252 return export_list[i].export; 253 } 254 return export_unknown; 255 } 256 257 static enum export export_from_sec(struct elf_info *elf, unsigned int sec) 258 { 259 if (sec == elf->export_sec) 260 return export_plain; 261 else if (sec == elf->export_unused_sec) 262 return export_unused; 263 else if (sec == elf->export_gpl_sec) 264 return export_gpl; 265 else if (sec == elf->export_unused_gpl_sec) 266 return export_unused_gpl; 267 else if (sec == elf->export_gpl_future_sec) 268 return export_gpl_future; 269 else 270 return export_unknown; 271 } 272 273 /** 274 * Add an exported symbol - it may have already been added without a 275 * CRC, in this case just update the CRC 276 **/ 277 static struct symbol *sym_add_exported(const char *name, struct module *mod, 278 enum export export) 279 { 280 struct symbol *s = find_symbol(name); 281 282 if (!s) { 283 s = new_symbol(name, mod, export); 284 } else { 285 if (!s->preloaded) { 286 warn("%s: '%s' exported twice. Previous export " 287 "was in %s%s\n", mod->name, name, 288 s->module->name, 289 is_vmlinux(s->module->name) ?"":".ko"); 290 } else { 291 /* In case Modules.symvers was out of date */ 292 s->module = mod; 293 } 294 } 295 s->preloaded = 0; 296 s->vmlinux = is_vmlinux(mod->name); 297 s->kernel = 0; 298 s->export = export; 299 return s; 300 } 301 302 static void sym_update_crc(const char *name, struct module *mod, 303 unsigned int crc, enum export export) 304 { 305 struct symbol *s = find_symbol(name); 306 307 if (!s) 308 s = new_symbol(name, mod, export); 309 s->crc = crc; 310 s->crc_valid = 1; 311 } 312 313 void *grab_file(const char *filename, unsigned long *size) 314 { 315 struct stat st; 316 void *map; 317 int fd; 318 319 fd = open(filename, O_RDONLY); 320 if (fd < 0 || fstat(fd, &st) != 0) 321 return NULL; 322 323 *size = st.st_size; 324 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); 325 close(fd); 326 327 if (map == MAP_FAILED) 328 return NULL; 329 return map; 330 } 331 332 /** 333 * Return a copy of the next line in a mmap'ed file. 334 * spaces in the beginning of the line is trimmed away. 335 * Return a pointer to a static buffer. 336 **/ 337 char *get_next_line(unsigned long *pos, void *file, unsigned long size) 338 { 339 static char line[4096]; 340 int skip = 1; 341 size_t len = 0; 342 signed char *p = (signed char *)file + *pos; 343 char *s = line; 344 345 for (; *pos < size ; (*pos)++) { 346 if (skip && isspace(*p)) { 347 p++; 348 continue; 349 } 350 skip = 0; 351 if (*p != '\n' && (*pos < size)) { 352 len++; 353 *s++ = *p++; 354 if (len > 4095) 355 break; /* Too long, stop */ 356 } else { 357 /* End of string */ 358 *s = '\0'; 359 return line; 360 } 361 } 362 /* End of buffer */ 363 return NULL; 364 } 365 366 void release_file(void *file, unsigned long size) 367 { 368 munmap(file, size); 369 } 370 371 static int parse_elf(struct elf_info *info, const char *filename) 372 { 373 unsigned int i; 374 Elf_Ehdr *hdr; 375 Elf_Shdr *sechdrs; 376 Elf_Sym *sym; 377 const char *secstrings; 378 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U; 379 380 hdr = grab_file(filename, &info->size); 381 if (!hdr) { 382 perror(filename); 383 exit(1); 384 } 385 info->hdr = hdr; 386 if (info->size < sizeof(*hdr)) { 387 /* file too small, assume this is an empty .o file */ 388 return 0; 389 } 390 /* Is this a valid ELF file? */ 391 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) || 392 (hdr->e_ident[EI_MAG1] != ELFMAG1) || 393 (hdr->e_ident[EI_MAG2] != ELFMAG2) || 394 (hdr->e_ident[EI_MAG3] != ELFMAG3)) { 395 /* Not an ELF file - silently ignore it */ 396 return 0; 397 } 398 /* Fix endianness in ELF header */ 399 hdr->e_type = TO_NATIVE(hdr->e_type); 400 hdr->e_machine = TO_NATIVE(hdr->e_machine); 401 hdr->e_version = TO_NATIVE(hdr->e_version); 402 hdr->e_entry = TO_NATIVE(hdr->e_entry); 403 hdr->e_phoff = TO_NATIVE(hdr->e_phoff); 404 hdr->e_shoff = TO_NATIVE(hdr->e_shoff); 405 hdr->e_flags = TO_NATIVE(hdr->e_flags); 406 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize); 407 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize); 408 hdr->e_phnum = TO_NATIVE(hdr->e_phnum); 409 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize); 410 hdr->e_shnum = TO_NATIVE(hdr->e_shnum); 411 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx); 412 sechdrs = (void *)hdr + hdr->e_shoff; 413 info->sechdrs = sechdrs; 414 415 /* Check if file offset is correct */ 416 if (hdr->e_shoff > info->size) { 417 fatal("section header offset=%lu in file '%s' is bigger than " 418 "filesize=%lu\n", (unsigned long)hdr->e_shoff, 419 filename, info->size); 420 return 0; 421 } 422 423 if (hdr->e_shnum == 0) { 424 /* 425 * There are more than 64k sections, 426 * read count from .sh_size. 427 * note: it doesn't need shndx2secindex() 428 */ 429 info->num_sections = TO_NATIVE(sechdrs[0].sh_size); 430 } 431 else { 432 info->num_sections = hdr->e_shnum; 433 } 434 if (hdr->e_shstrndx == SHN_XINDEX) { 435 info->secindex_strings = 436 shndx2secindex(TO_NATIVE(sechdrs[0].sh_link)); 437 } 438 else { 439 info->secindex_strings = hdr->e_shstrndx; 440 } 441 442 /* Fix endianness in section headers */ 443 for (i = 0; i < info->num_sections; i++) { 444 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name); 445 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); 446 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags); 447 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr); 448 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset); 449 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size); 450 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link); 451 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info); 452 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign); 453 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize); 454 } 455 /* Find symbol table. */ 456 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset; 457 for (i = 1; i < info->num_sections; i++) { 458 const char *secname; 459 int nobits = sechdrs[i].sh_type == SHT_NOBITS; 460 461 if (!nobits && sechdrs[i].sh_offset > info->size) { 462 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > " 463 "sizeof(*hrd)=%zu\n", filename, 464 (unsigned long)sechdrs[i].sh_offset, 465 sizeof(*hdr)); 466 return 0; 467 } 468 secname = secstrings + sechdrs[i].sh_name; 469 if (strcmp(secname, ".modinfo") == 0) { 470 if (nobits) 471 fatal("%s has NOBITS .modinfo\n", filename); 472 info->modinfo = (void *)hdr + sechdrs[i].sh_offset; 473 info->modinfo_len = sechdrs[i].sh_size; 474 } else if (strcmp(secname, "__ksymtab") == 0) 475 info->export_sec = i; 476 else if (strcmp(secname, "__ksymtab_unused") == 0) 477 info->export_unused_sec = i; 478 else if (strcmp(secname, "__ksymtab_gpl") == 0) 479 info->export_gpl_sec = i; 480 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0) 481 info->export_unused_gpl_sec = i; 482 else if (strcmp(secname, "__ksymtab_gpl_future") == 0) 483 info->export_gpl_future_sec = i; 484 485 if (sechdrs[i].sh_type == SHT_SYMTAB) { 486 unsigned int sh_link_idx; 487 symtab_idx = i; 488 info->symtab_start = (void *)hdr + 489 sechdrs[i].sh_offset; 490 info->symtab_stop = (void *)hdr + 491 sechdrs[i].sh_offset + sechdrs[i].sh_size; 492 sh_link_idx = shndx2secindex(sechdrs[i].sh_link); 493 info->strtab = (void *)hdr + 494 sechdrs[sh_link_idx].sh_offset; 495 } 496 497 /* 32bit section no. table? ("more than 64k sections") */ 498 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) { 499 symtab_shndx_idx = i; 500 info->symtab_shndx_start = (void *)hdr + 501 sechdrs[i].sh_offset; 502 info->symtab_shndx_stop = (void *)hdr + 503 sechdrs[i].sh_offset + sechdrs[i].sh_size; 504 } 505 } 506 if (!info->symtab_start) 507 fatal("%s has no symtab?\n", filename); 508 509 /* Fix endianness in symbols */ 510 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) { 511 sym->st_shndx = TO_NATIVE(sym->st_shndx); 512 sym->st_name = TO_NATIVE(sym->st_name); 513 sym->st_value = TO_NATIVE(sym->st_value); 514 sym->st_size = TO_NATIVE(sym->st_size); 515 } 516 517 if (symtab_shndx_idx != ~0U) { 518 Elf32_Word *p; 519 if (symtab_idx != 520 shndx2secindex(sechdrs[symtab_shndx_idx].sh_link)) 521 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n", 522 filename, 523 shndx2secindex(sechdrs[symtab_shndx_idx].sh_link), 524 symtab_idx); 525 /* Fix endianness */ 526 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop; 527 p++) 528 *p = TO_NATIVE(*p); 529 } 530 531 return 1; 532 } 533 534 static void parse_elf_finish(struct elf_info *info) 535 { 536 release_file(info->hdr, info->size); 537 } 538 539 static int ignore_undef_symbol(struct elf_info *info, const char *symname) 540 { 541 /* ignore __this_module, it will be resolved shortly */ 542 if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0) 543 return 1; 544 /* ignore global offset table */ 545 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0) 546 return 1; 547 if (info->hdr->e_machine == EM_PPC) 548 /* Special register function linked on all modules during final link of .ko */ 549 if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 || 550 strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 || 551 strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 || 552 strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0) 553 return 1; 554 if (info->hdr->e_machine == EM_PPC64) 555 /* Special register function linked on all modules during final link of .ko */ 556 if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 || 557 strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0) 558 return 1; 559 /* Do not ignore this symbol */ 560 return 0; 561 } 562 563 #define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_" 564 #define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_" 565 566 static void handle_modversions(struct module *mod, struct elf_info *info, 567 Elf_Sym *sym, const char *symname) 568 { 569 unsigned int crc; 570 enum export export = export_from_sec(info, get_secindex(info, sym)); 571 572 switch (sym->st_shndx) { 573 case SHN_COMMON: 574 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name); 575 break; 576 case SHN_ABS: 577 /* CRC'd symbol */ 578 if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) { 579 crc = (unsigned int) sym->st_value; 580 sym_update_crc(symname + strlen(CRC_PFX), mod, crc, 581 export); 582 } 583 break; 584 case SHN_UNDEF: 585 /* undefined symbol */ 586 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 587 ELF_ST_BIND(sym->st_info) != STB_WEAK) 588 break; 589 if (ignore_undef_symbol(info, symname)) 590 break; 591 /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */ 592 #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER) 593 /* add compatibility with older glibc */ 594 #ifndef STT_SPARC_REGISTER 595 #define STT_SPARC_REGISTER STT_REGISTER 596 #endif 597 if (info->hdr->e_machine == EM_SPARC || 598 info->hdr->e_machine == EM_SPARCV9) { 599 /* Ignore register directives. */ 600 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER) 601 break; 602 if (symname[0] == '.') { 603 char *munged = strdup(symname); 604 munged[0] = '_'; 605 munged[1] = toupper(munged[1]); 606 symname = munged; 607 } 608 } 609 #endif 610 611 if (memcmp(symname, MODULE_SYMBOL_PREFIX, 612 strlen(MODULE_SYMBOL_PREFIX)) == 0) { 613 mod->unres = 614 alloc_symbol(symname + 615 strlen(MODULE_SYMBOL_PREFIX), 616 ELF_ST_BIND(sym->st_info) == STB_WEAK, 617 mod->unres); 618 } 619 break; 620 default: 621 /* All exported symbols */ 622 if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) { 623 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod, 624 export); 625 } 626 if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0) 627 mod->has_init = 1; 628 if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0) 629 mod->has_cleanup = 1; 630 break; 631 } 632 } 633 634 /** 635 * Parse tag=value strings from .modinfo section 636 **/ 637 static char *next_string(char *string, unsigned long *secsize) 638 { 639 /* Skip non-zero chars */ 640 while (string[0]) { 641 string++; 642 if ((*secsize)-- <= 1) 643 return NULL; 644 } 645 646 /* Skip any zero padding. */ 647 while (!string[0]) { 648 string++; 649 if ((*secsize)-- <= 1) 650 return NULL; 651 } 652 return string; 653 } 654 655 static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len, 656 const char *tag, char *info) 657 { 658 char *p; 659 unsigned int taglen = strlen(tag); 660 unsigned long size = modinfo_len; 661 662 if (info) { 663 size -= info - (char *)modinfo; 664 modinfo = next_string(info, &size); 665 } 666 667 for (p = modinfo; p; p = next_string(p, &size)) { 668 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') 669 return p + taglen + 1; 670 } 671 return NULL; 672 } 673 674 static char *get_modinfo(void *modinfo, unsigned long modinfo_len, 675 const char *tag) 676 677 { 678 return get_next_modinfo(modinfo, modinfo_len, tag, NULL); 679 } 680 681 /** 682 * Test if string s ends in string sub 683 * return 0 if match 684 **/ 685 static int strrcmp(const char *s, const char *sub) 686 { 687 int slen, sublen; 688 689 if (!s || !sub) 690 return 1; 691 692 slen = strlen(s); 693 sublen = strlen(sub); 694 695 if ((slen == 0) || (sublen == 0)) 696 return 1; 697 698 if (sublen > slen) 699 return 1; 700 701 return memcmp(s + slen - sublen, sub, sublen); 702 } 703 704 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) 705 { 706 if (sym) 707 return elf->strtab + sym->st_name; 708 else 709 return "(unknown)"; 710 } 711 712 static const char *sec_name(struct elf_info *elf, int secindex) 713 { 714 Elf_Shdr *sechdrs = elf->sechdrs; 715 return (void *)elf->hdr + 716 elf->sechdrs[elf->secindex_strings].sh_offset + 717 sechdrs[secindex].sh_name; 718 } 719 720 static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr) 721 { 722 return (void *)elf->hdr + 723 elf->sechdrs[elf->secindex_strings].sh_offset + 724 sechdr->sh_name; 725 } 726 727 /* if sym is empty or point to a string 728 * like ".[0-9]+" then return 1. 729 * This is the optional prefix added by ld to some sections 730 */ 731 static int number_prefix(const char *sym) 732 { 733 if (*sym++ == '\0') 734 return 1; 735 if (*sym != '.') 736 return 0; 737 do { 738 char c = *sym++; 739 if (c < '0' || c > '9') 740 return 0; 741 } while (*sym); 742 return 1; 743 } 744 745 /* The pattern is an array of simple patterns. 746 * "foo" will match an exact string equal to "foo" 747 * "*foo" will match a string that ends with "foo" 748 * "foo*" will match a string that begins with "foo" 749 * "foo$" will match a string equal to "foo" or "foo.1" 750 * where the '1' can be any number including several digits. 751 * The $ syntax is for sections where ld append a dot number 752 * to make section name unique. 753 */ 754 static int match(const char *sym, const char * const pat[]) 755 { 756 const char *p; 757 while (*pat) { 758 p = *pat++; 759 const char *endp = p + strlen(p) - 1; 760 761 /* "*foo" */ 762 if (*p == '*') { 763 if (strrcmp(sym, p + 1) == 0) 764 return 1; 765 } 766 /* "foo*" */ 767 else if (*endp == '*') { 768 if (strncmp(sym, p, strlen(p) - 1) == 0) 769 return 1; 770 } 771 /* "foo$" */ 772 else if (*endp == '$') { 773 if (strncmp(sym, p, strlen(p) - 1) == 0) { 774 if (number_prefix(sym + strlen(p) - 1)) 775 return 1; 776 } 777 } 778 /* no wildcards */ 779 else { 780 if (strcmp(p, sym) == 0) 781 return 1; 782 } 783 } 784 /* no match */ 785 return 0; 786 } 787 788 /* sections that we do not want to do full section mismatch check on */ 789 static const char *section_white_list[] = 790 { 791 ".comment*", 792 ".debug*", 793 ".zdebug*", /* Compressed debug sections. */ 794 ".GCC-command-line", /* mn10300 */ 795 ".mdebug*", /* alpha, score, mips etc. */ 796 ".pdr", /* alpha, score, mips etc. */ 797 ".stab*", 798 ".note*", 799 ".got*", 800 ".toc*", 801 NULL 802 }; 803 804 /* 805 * This is used to find sections missing the SHF_ALLOC flag. 806 * The cause of this is often a section specified in assembler 807 * without "ax" / "aw". 808 */ 809 static void check_section(const char *modname, struct elf_info *elf, 810 Elf_Shdr *sechdr) 811 { 812 const char *sec = sech_name(elf, sechdr); 813 814 if (sechdr->sh_type == SHT_PROGBITS && 815 !(sechdr->sh_flags & SHF_ALLOC) && 816 !match(sec, section_white_list)) { 817 warn("%s (%s): unexpected non-allocatable section.\n" 818 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n" 819 "Note that for example <linux/init.h> contains\n" 820 "section definitions for use in .S files.\n\n", 821 modname, sec); 822 } 823 } 824 825 826 827 #define ALL_INIT_DATA_SECTIONS \ 828 ".init.setup$", ".init.rodata$", \ 829 ".devinit.rodata$", ".cpuinit.rodata$", ".meminit.rodata$" \ 830 ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$" 831 #define ALL_EXIT_DATA_SECTIONS \ 832 ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$" 833 834 #define ALL_INIT_TEXT_SECTIONS \ 835 ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$" 836 #define ALL_EXIT_TEXT_SECTIONS \ 837 ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$" 838 839 #define ALL_XXXINIT_SECTIONS DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, \ 840 MEM_INIT_SECTIONS 841 #define ALL_XXXEXIT_SECTIONS DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, \ 842 MEM_EXIT_SECTIONS 843 844 #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS 845 #define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS 846 847 #define DATA_SECTIONS ".data$", ".data.rel$" 848 #define TEXT_SECTIONS ".text$" 849 850 #define INIT_SECTIONS ".init.*" 851 #define DEV_INIT_SECTIONS ".devinit.*" 852 #define CPU_INIT_SECTIONS ".cpuinit.*" 853 #define MEM_INIT_SECTIONS ".meminit.*" 854 855 #define EXIT_SECTIONS ".exit.*" 856 #define DEV_EXIT_SECTIONS ".devexit.*" 857 #define CPU_EXIT_SECTIONS ".cpuexit.*" 858 #define MEM_EXIT_SECTIONS ".memexit.*" 859 860 /* init data sections */ 861 static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL }; 862 863 /* all init sections */ 864 static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL }; 865 866 /* All init and exit sections (code + data) */ 867 static const char *init_exit_sections[] = 868 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }; 869 870 /* data section */ 871 static const char *data_sections[] = { DATA_SECTIONS, NULL }; 872 873 874 /* symbols in .data that may refer to init/exit sections */ 875 #define DEFAULT_SYMBOL_WHITE_LIST \ 876 "*driver", \ 877 "*_template", /* scsi uses *_template a lot */ \ 878 "*_timer", /* arm uses ops structures named _timer a lot */ \ 879 "*_sht", /* scsi also used *_sht to some extent */ \ 880 "*_ops", \ 881 "*_probe", \ 882 "*_probe_one", \ 883 "*_console" 884 885 static const char *head_sections[] = { ".head.text*", NULL }; 886 static const char *linker_symbols[] = 887 { "__init_begin", "_sinittext", "_einittext", NULL }; 888 889 enum mismatch { 890 TEXT_TO_ANY_INIT, 891 DATA_TO_ANY_INIT, 892 TEXT_TO_ANY_EXIT, 893 DATA_TO_ANY_EXIT, 894 XXXINIT_TO_SOME_INIT, 895 XXXEXIT_TO_SOME_EXIT, 896 ANY_INIT_TO_ANY_EXIT, 897 ANY_EXIT_TO_ANY_INIT, 898 EXPORT_TO_INIT_EXIT, 899 }; 900 901 struct sectioncheck { 902 const char *fromsec[20]; 903 const char *tosec[20]; 904 enum mismatch mismatch; 905 const char *symbol_white_list[20]; 906 }; 907 908 const struct sectioncheck sectioncheck[] = { 909 /* Do not reference init/exit code/data from 910 * normal code and data 911 */ 912 { 913 .fromsec = { TEXT_SECTIONS, NULL }, 914 .tosec = { ALL_INIT_SECTIONS, NULL }, 915 .mismatch = TEXT_TO_ANY_INIT, 916 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 917 }, 918 { 919 .fromsec = { DATA_SECTIONS, NULL }, 920 .tosec = { ALL_XXXINIT_SECTIONS, NULL }, 921 .mismatch = DATA_TO_ANY_INIT, 922 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 923 }, 924 { 925 .fromsec = { DATA_SECTIONS, NULL }, 926 .tosec = { INIT_SECTIONS, NULL }, 927 .mismatch = DATA_TO_ANY_INIT, 928 .symbol_white_list = { 929 "*_template", "*_timer", "*_sht", "*_ops", 930 "*_probe", "*_probe_one", "*_console", NULL 931 }, 932 }, 933 { 934 .fromsec = { TEXT_SECTIONS, NULL }, 935 .tosec = { ALL_EXIT_SECTIONS, NULL }, 936 .mismatch = TEXT_TO_ANY_EXIT, 937 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 938 }, 939 { 940 .fromsec = { DATA_SECTIONS, NULL }, 941 .tosec = { ALL_EXIT_SECTIONS, NULL }, 942 .mismatch = DATA_TO_ANY_EXIT, 943 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 944 }, 945 /* Do not reference init code/data from devinit/cpuinit/meminit code/data */ 946 { 947 .fromsec = { ALL_XXXINIT_SECTIONS, NULL }, 948 .tosec = { INIT_SECTIONS, NULL }, 949 .mismatch = XXXINIT_TO_SOME_INIT, 950 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 951 }, 952 /* Do not reference cpuinit code/data from meminit code/data */ 953 { 954 .fromsec = { MEM_INIT_SECTIONS, NULL }, 955 .tosec = { CPU_INIT_SECTIONS, NULL }, 956 .mismatch = XXXINIT_TO_SOME_INIT, 957 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 958 }, 959 /* Do not reference meminit code/data from cpuinit code/data */ 960 { 961 .fromsec = { CPU_INIT_SECTIONS, NULL }, 962 .tosec = { MEM_INIT_SECTIONS, NULL }, 963 .mismatch = XXXINIT_TO_SOME_INIT, 964 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 965 }, 966 /* Do not reference exit code/data from devexit/cpuexit/memexit code/data */ 967 { 968 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL }, 969 .tosec = { EXIT_SECTIONS, NULL }, 970 .mismatch = XXXEXIT_TO_SOME_EXIT, 971 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 972 }, 973 /* Do not reference cpuexit code/data from memexit code/data */ 974 { 975 .fromsec = { MEM_EXIT_SECTIONS, NULL }, 976 .tosec = { CPU_EXIT_SECTIONS, NULL }, 977 .mismatch = XXXEXIT_TO_SOME_EXIT, 978 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 979 }, 980 /* Do not reference memexit code/data from cpuexit code/data */ 981 { 982 .fromsec = { CPU_EXIT_SECTIONS, NULL }, 983 .tosec = { MEM_EXIT_SECTIONS, NULL }, 984 .mismatch = XXXEXIT_TO_SOME_EXIT, 985 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 986 }, 987 /* Do not use exit code/data from init code */ 988 { 989 .fromsec = { ALL_INIT_SECTIONS, NULL }, 990 .tosec = { ALL_EXIT_SECTIONS, NULL }, 991 .mismatch = ANY_INIT_TO_ANY_EXIT, 992 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 993 }, 994 /* Do not use init code/data from exit code */ 995 { 996 .fromsec = { ALL_EXIT_SECTIONS, NULL }, 997 .tosec = { ALL_INIT_SECTIONS, NULL }, 998 .mismatch = ANY_EXIT_TO_ANY_INIT, 999 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 1000 }, 1001 /* Do not export init/exit functions or data */ 1002 { 1003 .fromsec = { "__ksymtab*", NULL }, 1004 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL }, 1005 .mismatch = EXPORT_TO_INIT_EXIT, 1006 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 1007 } 1008 }; 1009 1010 static const struct sectioncheck *section_mismatch( 1011 const char *fromsec, const char *tosec) 1012 { 1013 int i; 1014 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck); 1015 const struct sectioncheck *check = §ioncheck[0]; 1016 1017 for (i = 0; i < elems; i++) { 1018 if (match(fromsec, check->fromsec) && 1019 match(tosec, check->tosec)) 1020 return check; 1021 check++; 1022 } 1023 return NULL; 1024 } 1025 1026 /** 1027 * Whitelist to allow certain references to pass with no warning. 1028 * 1029 * Pattern 1: 1030 * If a module parameter is declared __initdata and permissions=0 1031 * then this is legal despite the warning generated. 1032 * We cannot see value of permissions here, so just ignore 1033 * this pattern. 1034 * The pattern is identified by: 1035 * tosec = .init.data 1036 * fromsec = .data* 1037 * atsym =__param* 1038 * 1039 * Pattern 1a: 1040 * module_param_call() ops can refer to __init set function if permissions=0 1041 * The pattern is identified by: 1042 * tosec = .init.text 1043 * fromsec = .data* 1044 * atsym = __param_ops_* 1045 * 1046 * Pattern 2: 1047 * Many drivers utilise a *driver container with references to 1048 * add, remove, probe functions etc. 1049 * These functions may often be marked __devinit and we do not want to 1050 * warn here. 1051 * the pattern is identified by: 1052 * tosec = init or exit section 1053 * fromsec = data section 1054 * atsym = *driver, *_template, *_sht, *_ops, *_probe, 1055 * *probe_one, *_console, *_timer 1056 * 1057 * Pattern 3: 1058 * Whitelist all references from .head.text to any init section 1059 * 1060 * Pattern 4: 1061 * Some symbols belong to init section but still it is ok to reference 1062 * these from non-init sections as these symbols don't have any memory 1063 * allocated for them and symbol address and value are same. So even 1064 * if init section is freed, its ok to reference those symbols. 1065 * For ex. symbols marking the init section boundaries. 1066 * This pattern is identified by 1067 * refsymname = __init_begin, _sinittext, _einittext 1068 * 1069 **/ 1070 static int secref_whitelist(const struct sectioncheck *mismatch, 1071 const char *fromsec, const char *fromsym, 1072 const char *tosec, const char *tosym) 1073 { 1074 /* Check for pattern 1 */ 1075 if (match(tosec, init_data_sections) && 1076 match(fromsec, data_sections) && 1077 (strncmp(fromsym, "__param", strlen("__param")) == 0)) 1078 return 0; 1079 1080 /* Check for pattern 1a */ 1081 if (strcmp(tosec, ".init.text") == 0 && 1082 match(fromsec, data_sections) && 1083 (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0)) 1084 return 0; 1085 1086 /* Check for pattern 2 */ 1087 if (match(tosec, init_exit_sections) && 1088 match(fromsec, data_sections) && 1089 match(fromsym, mismatch->symbol_white_list)) 1090 return 0; 1091 1092 /* Check for pattern 3 */ 1093 if (match(fromsec, head_sections) && 1094 match(tosec, init_sections)) 1095 return 0; 1096 1097 /* Check for pattern 4 */ 1098 if (match(tosym, linker_symbols)) 1099 return 0; 1100 1101 return 1; 1102 } 1103 1104 /** 1105 * Find symbol based on relocation record info. 1106 * In some cases the symbol supplied is a valid symbol so 1107 * return refsym. If st_name != 0 we assume this is a valid symbol. 1108 * In other cases the symbol needs to be looked up in the symbol table 1109 * based on section and address. 1110 * **/ 1111 static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr, 1112 Elf_Sym *relsym) 1113 { 1114 Elf_Sym *sym; 1115 Elf_Sym *near = NULL; 1116 Elf64_Sword distance = 20; 1117 Elf64_Sword d; 1118 unsigned int relsym_secindex; 1119 1120 if (relsym->st_name != 0) 1121 return relsym; 1122 1123 relsym_secindex = get_secindex(elf, relsym); 1124 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { 1125 if (get_secindex(elf, sym) != relsym_secindex) 1126 continue; 1127 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION) 1128 continue; 1129 if (sym->st_value == addr) 1130 return sym; 1131 /* Find a symbol nearby - addr are maybe negative */ 1132 d = sym->st_value - addr; 1133 if (d < 0) 1134 d = addr - sym->st_value; 1135 if (d < distance) { 1136 distance = d; 1137 near = sym; 1138 } 1139 } 1140 /* We need a close match */ 1141 if (distance < 20) 1142 return near; 1143 else 1144 return NULL; 1145 } 1146 1147 static inline int is_arm_mapping_symbol(const char *str) 1148 { 1149 return str[0] == '$' && strchr("atd", str[1]) 1150 && (str[2] == '\0' || str[2] == '.'); 1151 } 1152 1153 /* 1154 * If there's no name there, ignore it; likewise, ignore it if it's 1155 * one of the magic symbols emitted used by current ARM tools. 1156 * 1157 * Otherwise if find_symbols_between() returns those symbols, they'll 1158 * fail the whitelist tests and cause lots of false alarms ... fixable 1159 * only by merging __exit and __init sections into __text, bloating 1160 * the kernel (which is especially evil on embedded platforms). 1161 */ 1162 static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym) 1163 { 1164 const char *name = elf->strtab + sym->st_name; 1165 1166 if (!name || !strlen(name)) 1167 return 0; 1168 return !is_arm_mapping_symbol(name); 1169 } 1170 1171 /* 1172 * Find symbols before or equal addr and after addr - in the section sec. 1173 * If we find two symbols with equal offset prefer one with a valid name. 1174 * The ELF format may have a better way to detect what type of symbol 1175 * it is, but this works for now. 1176 **/ 1177 static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr, 1178 const char *sec) 1179 { 1180 Elf_Sym *sym; 1181 Elf_Sym *near = NULL; 1182 Elf_Addr distance = ~0; 1183 1184 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { 1185 const char *symsec; 1186 1187 if (is_shndx_special(sym->st_shndx)) 1188 continue; 1189 symsec = sec_name(elf, get_secindex(elf, sym)); 1190 if (strcmp(symsec, sec) != 0) 1191 continue; 1192 if (!is_valid_name(elf, sym)) 1193 continue; 1194 if (sym->st_value <= addr) { 1195 if ((addr - sym->st_value) < distance) { 1196 distance = addr - sym->st_value; 1197 near = sym; 1198 } else if ((addr - sym->st_value) == distance) { 1199 near = sym; 1200 } 1201 } 1202 } 1203 return near; 1204 } 1205 1206 /* 1207 * Convert a section name to the function/data attribute 1208 * .init.text => __init 1209 * .cpuinit.data => __cpudata 1210 * .memexitconst => __memconst 1211 * etc. 1212 * 1213 * The memory of returned value has been allocated on a heap. The user of this 1214 * method should free it after usage. 1215 */ 1216 static char *sec2annotation(const char *s) 1217 { 1218 if (match(s, init_exit_sections)) { 1219 char *p = malloc(20); 1220 char *r = p; 1221 1222 *p++ = '_'; 1223 *p++ = '_'; 1224 if (*s == '.') 1225 s++; 1226 while (*s && *s != '.') 1227 *p++ = *s++; 1228 *p = '\0'; 1229 if (*s == '.') 1230 s++; 1231 if (strstr(s, "rodata") != NULL) 1232 strcat(p, "const "); 1233 else if (strstr(s, "data") != NULL) 1234 strcat(p, "data "); 1235 else 1236 strcat(p, " "); 1237 return r; 1238 } else { 1239 return strdup(""); 1240 } 1241 } 1242 1243 static int is_function(Elf_Sym *sym) 1244 { 1245 if (sym) 1246 return ELF_ST_TYPE(sym->st_info) == STT_FUNC; 1247 else 1248 return -1; 1249 } 1250 1251 static void print_section_list(const char * const list[20]) 1252 { 1253 const char *const *s = list; 1254 1255 while (*s) { 1256 fprintf(stderr, "%s", *s); 1257 s++; 1258 if (*s) 1259 fprintf(stderr, ", "); 1260 } 1261 fprintf(stderr, "\n"); 1262 } 1263 1264 /* 1265 * Print a warning about a section mismatch. 1266 * Try to find symbols near it so user can find it. 1267 * Check whitelist before warning - it may be a false positive. 1268 */ 1269 static void report_sec_mismatch(const char *modname, 1270 const struct sectioncheck *mismatch, 1271 const char *fromsec, 1272 unsigned long long fromaddr, 1273 const char *fromsym, 1274 int from_is_func, 1275 const char *tosec, const char *tosym, 1276 int to_is_func) 1277 { 1278 const char *from, *from_p; 1279 const char *to, *to_p; 1280 char *prl_from; 1281 char *prl_to; 1282 1283 switch (from_is_func) { 1284 case 0: from = "variable"; from_p = ""; break; 1285 case 1: from = "function"; from_p = "()"; break; 1286 default: from = "(unknown reference)"; from_p = ""; break; 1287 } 1288 switch (to_is_func) { 1289 case 0: to = "variable"; to_p = ""; break; 1290 case 1: to = "function"; to_p = "()"; break; 1291 default: to = "(unknown reference)"; to_p = ""; break; 1292 } 1293 1294 sec_mismatch_count++; 1295 if (!sec_mismatch_verbose) 1296 return; 1297 1298 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s " 1299 "to the %s %s:%s%s\n", 1300 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec, 1301 tosym, to_p); 1302 1303 switch (mismatch->mismatch) { 1304 case TEXT_TO_ANY_INIT: 1305 prl_from = sec2annotation(fromsec); 1306 prl_to = sec2annotation(tosec); 1307 fprintf(stderr, 1308 "The function %s%s() references\n" 1309 "the %s %s%s%s.\n" 1310 "This is often because %s lacks a %s\n" 1311 "annotation or the annotation of %s is wrong.\n", 1312 prl_from, fromsym, 1313 to, prl_to, tosym, to_p, 1314 fromsym, prl_to, tosym); 1315 free(prl_from); 1316 free(prl_to); 1317 break; 1318 case DATA_TO_ANY_INIT: { 1319 prl_to = sec2annotation(tosec); 1320 fprintf(stderr, 1321 "The variable %s references\n" 1322 "the %s %s%s%s\n" 1323 "If the reference is valid then annotate the\n" 1324 "variable with __init* or __refdata (see linux/init.h) " 1325 "or name the variable:\n", 1326 fromsym, to, prl_to, tosym, to_p); 1327 print_section_list(mismatch->symbol_white_list); 1328 free(prl_to); 1329 break; 1330 } 1331 case TEXT_TO_ANY_EXIT: 1332 prl_to = sec2annotation(tosec); 1333 fprintf(stderr, 1334 "The function %s() references a %s in an exit section.\n" 1335 "Often the %s %s%s has valid usage outside the exit section\n" 1336 "and the fix is to remove the %sannotation of %s.\n", 1337 fromsym, to, to, tosym, to_p, prl_to, tosym); 1338 free(prl_to); 1339 break; 1340 case DATA_TO_ANY_EXIT: { 1341 prl_to = sec2annotation(tosec); 1342 fprintf(stderr, 1343 "The variable %s references\n" 1344 "the %s %s%s%s\n" 1345 "If the reference is valid then annotate the\n" 1346 "variable with __exit* (see linux/init.h) or " 1347 "name the variable:\n", 1348 fromsym, to, prl_to, tosym, to_p); 1349 print_section_list(mismatch->symbol_white_list); 1350 free(prl_to); 1351 break; 1352 } 1353 case XXXINIT_TO_SOME_INIT: 1354 case XXXEXIT_TO_SOME_EXIT: 1355 prl_from = sec2annotation(fromsec); 1356 prl_to = sec2annotation(tosec); 1357 fprintf(stderr, 1358 "The %s %s%s%s references\n" 1359 "a %s %s%s%s.\n" 1360 "If %s is only used by %s then\n" 1361 "annotate %s with a matching annotation.\n", 1362 from, prl_from, fromsym, from_p, 1363 to, prl_to, tosym, to_p, 1364 tosym, fromsym, tosym); 1365 free(prl_from); 1366 free(prl_to); 1367 break; 1368 case ANY_INIT_TO_ANY_EXIT: 1369 prl_from = sec2annotation(fromsec); 1370 prl_to = sec2annotation(tosec); 1371 fprintf(stderr, 1372 "The %s %s%s%s references\n" 1373 "a %s %s%s%s.\n" 1374 "This is often seen when error handling " 1375 "in the init function\n" 1376 "uses functionality in the exit path.\n" 1377 "The fix is often to remove the %sannotation of\n" 1378 "%s%s so it may be used outside an exit section.\n", 1379 from, prl_from, fromsym, from_p, 1380 to, prl_to, tosym, to_p, 1381 prl_to, tosym, to_p); 1382 free(prl_from); 1383 free(prl_to); 1384 break; 1385 case ANY_EXIT_TO_ANY_INIT: 1386 prl_from = sec2annotation(fromsec); 1387 prl_to = sec2annotation(tosec); 1388 fprintf(stderr, 1389 "The %s %s%s%s references\n" 1390 "a %s %s%s%s.\n" 1391 "This is often seen when error handling " 1392 "in the exit function\n" 1393 "uses functionality in the init path.\n" 1394 "The fix is often to remove the %sannotation of\n" 1395 "%s%s so it may be used outside an init section.\n", 1396 from, prl_from, fromsym, from_p, 1397 to, prl_to, tosym, to_p, 1398 prl_to, tosym, to_p); 1399 free(prl_from); 1400 free(prl_to); 1401 break; 1402 case EXPORT_TO_INIT_EXIT: 1403 prl_to = sec2annotation(tosec); 1404 fprintf(stderr, 1405 "The symbol %s is exported and annotated %s\n" 1406 "Fix this by removing the %sannotation of %s " 1407 "or drop the export.\n", 1408 tosym, prl_to, prl_to, tosym); 1409 free(prl_to); 1410 break; 1411 } 1412 fprintf(stderr, "\n"); 1413 } 1414 1415 static void check_section_mismatch(const char *modname, struct elf_info *elf, 1416 Elf_Rela *r, Elf_Sym *sym, const char *fromsec) 1417 { 1418 const char *tosec; 1419 const struct sectioncheck *mismatch; 1420 1421 tosec = sec_name(elf, get_secindex(elf, sym)); 1422 mismatch = section_mismatch(fromsec, tosec); 1423 if (mismatch) { 1424 Elf_Sym *to; 1425 Elf_Sym *from; 1426 const char *tosym; 1427 const char *fromsym; 1428 1429 from = find_elf_symbol2(elf, r->r_offset, fromsec); 1430 fromsym = sym_name(elf, from); 1431 to = find_elf_symbol(elf, r->r_addend, sym); 1432 tosym = sym_name(elf, to); 1433 1434 /* check whitelist - we may ignore it */ 1435 if (secref_whitelist(mismatch, 1436 fromsec, fromsym, tosec, tosym)) { 1437 report_sec_mismatch(modname, mismatch, 1438 fromsec, r->r_offset, fromsym, 1439 is_function(from), tosec, tosym, 1440 is_function(to)); 1441 } 1442 } 1443 } 1444 1445 static unsigned int *reloc_location(struct elf_info *elf, 1446 Elf_Shdr *sechdr, Elf_Rela *r) 1447 { 1448 Elf_Shdr *sechdrs = elf->sechdrs; 1449 int section = shndx2secindex(sechdr->sh_info); 1450 1451 return (void *)elf->hdr + sechdrs[section].sh_offset + 1452 r->r_offset; 1453 } 1454 1455 static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1456 { 1457 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1458 unsigned int *location = reloc_location(elf, sechdr, r); 1459 1460 switch (r_typ) { 1461 case R_386_32: 1462 r->r_addend = TO_NATIVE(*location); 1463 break; 1464 case R_386_PC32: 1465 r->r_addend = TO_NATIVE(*location) + 4; 1466 /* For CONFIG_RELOCATABLE=y */ 1467 if (elf->hdr->e_type == ET_EXEC) 1468 r->r_addend += r->r_offset; 1469 break; 1470 } 1471 return 0; 1472 } 1473 1474 static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1475 { 1476 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1477 1478 switch (r_typ) { 1479 case R_ARM_ABS32: 1480 /* From ARM ABI: (S + A) | T */ 1481 r->r_addend = (int)(long) 1482 (elf->symtab_start + ELF_R_SYM(r->r_info)); 1483 break; 1484 case R_ARM_PC24: 1485 /* From ARM ABI: ((S + A) | T) - P */ 1486 r->r_addend = (int)(long)(elf->hdr + 1487 sechdr->sh_offset + 1488 (r->r_offset - sechdr->sh_addr)); 1489 break; 1490 default: 1491 return 1; 1492 } 1493 return 0; 1494 } 1495 1496 static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1497 { 1498 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1499 unsigned int *location = reloc_location(elf, sechdr, r); 1500 unsigned int inst; 1501 1502 if (r_typ == R_MIPS_HI16) 1503 return 1; /* skip this */ 1504 inst = TO_NATIVE(*location); 1505 switch (r_typ) { 1506 case R_MIPS_LO16: 1507 r->r_addend = inst & 0xffff; 1508 break; 1509 case R_MIPS_26: 1510 r->r_addend = (inst & 0x03ffffff) << 2; 1511 break; 1512 case R_MIPS_32: 1513 r->r_addend = inst; 1514 break; 1515 } 1516 return 0; 1517 } 1518 1519 static void section_rela(const char *modname, struct elf_info *elf, 1520 Elf_Shdr *sechdr) 1521 { 1522 Elf_Sym *sym; 1523 Elf_Rela *rela; 1524 Elf_Rela r; 1525 unsigned int r_sym; 1526 const char *fromsec; 1527 1528 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset; 1529 Elf_Rela *stop = (void *)start + sechdr->sh_size; 1530 1531 fromsec = sech_name(elf, sechdr); 1532 fromsec += strlen(".rela"); 1533 /* if from section (name) is know good then skip it */ 1534 if (match(fromsec, section_white_list)) 1535 return; 1536 1537 for (rela = start; rela < stop; rela++) { 1538 r.r_offset = TO_NATIVE(rela->r_offset); 1539 #if KERNEL_ELFCLASS == ELFCLASS64 1540 if (elf->hdr->e_machine == EM_MIPS) { 1541 unsigned int r_typ; 1542 r_sym = ELF64_MIPS_R_SYM(rela->r_info); 1543 r_sym = TO_NATIVE(r_sym); 1544 r_typ = ELF64_MIPS_R_TYPE(rela->r_info); 1545 r.r_info = ELF64_R_INFO(r_sym, r_typ); 1546 } else { 1547 r.r_info = TO_NATIVE(rela->r_info); 1548 r_sym = ELF_R_SYM(r.r_info); 1549 } 1550 #else 1551 r.r_info = TO_NATIVE(rela->r_info); 1552 r_sym = ELF_R_SYM(r.r_info); 1553 #endif 1554 r.r_addend = TO_NATIVE(rela->r_addend); 1555 sym = elf->symtab_start + r_sym; 1556 /* Skip special sections */ 1557 if (is_shndx_special(sym->st_shndx)) 1558 continue; 1559 check_section_mismatch(modname, elf, &r, sym, fromsec); 1560 } 1561 } 1562 1563 static void section_rel(const char *modname, struct elf_info *elf, 1564 Elf_Shdr *sechdr) 1565 { 1566 Elf_Sym *sym; 1567 Elf_Rel *rel; 1568 Elf_Rela r; 1569 unsigned int r_sym; 1570 const char *fromsec; 1571 1572 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset; 1573 Elf_Rel *stop = (void *)start + sechdr->sh_size; 1574 1575 fromsec = sech_name(elf, sechdr); 1576 fromsec += strlen(".rel"); 1577 /* if from section (name) is know good then skip it */ 1578 if (match(fromsec, section_white_list)) 1579 return; 1580 1581 for (rel = start; rel < stop; rel++) { 1582 r.r_offset = TO_NATIVE(rel->r_offset); 1583 #if KERNEL_ELFCLASS == ELFCLASS64 1584 if (elf->hdr->e_machine == EM_MIPS) { 1585 unsigned int r_typ; 1586 r_sym = ELF64_MIPS_R_SYM(rel->r_info); 1587 r_sym = TO_NATIVE(r_sym); 1588 r_typ = ELF64_MIPS_R_TYPE(rel->r_info); 1589 r.r_info = ELF64_R_INFO(r_sym, r_typ); 1590 } else { 1591 r.r_info = TO_NATIVE(rel->r_info); 1592 r_sym = ELF_R_SYM(r.r_info); 1593 } 1594 #else 1595 r.r_info = TO_NATIVE(rel->r_info); 1596 r_sym = ELF_R_SYM(r.r_info); 1597 #endif 1598 r.r_addend = 0; 1599 switch (elf->hdr->e_machine) { 1600 case EM_386: 1601 if (addend_386_rel(elf, sechdr, &r)) 1602 continue; 1603 break; 1604 case EM_ARM: 1605 if (addend_arm_rel(elf, sechdr, &r)) 1606 continue; 1607 break; 1608 case EM_MIPS: 1609 if (addend_mips_rel(elf, sechdr, &r)) 1610 continue; 1611 break; 1612 } 1613 sym = elf->symtab_start + r_sym; 1614 /* Skip special sections */ 1615 if (is_shndx_special(sym->st_shndx)) 1616 continue; 1617 check_section_mismatch(modname, elf, &r, sym, fromsec); 1618 } 1619 } 1620 1621 /** 1622 * A module includes a number of sections that are discarded 1623 * either when loaded or when used as built-in. 1624 * For loaded modules all functions marked __init and all data 1625 * marked __initdata will be discarded when the module has been initialized. 1626 * Likewise for modules used built-in the sections marked __exit 1627 * are discarded because __exit marked function are supposed to be called 1628 * only when a module is unloaded which never happens for built-in modules. 1629 * The check_sec_ref() function traverses all relocation records 1630 * to find all references to a section that reference a section that will 1631 * be discarded and warns about it. 1632 **/ 1633 static void check_sec_ref(struct module *mod, const char *modname, 1634 struct elf_info *elf) 1635 { 1636 int i; 1637 Elf_Shdr *sechdrs = elf->sechdrs; 1638 1639 /* Walk through all sections */ 1640 for (i = 0; i < elf->num_sections; i++) { 1641 check_section(modname, elf, &elf->sechdrs[i]); 1642 /* We want to process only relocation sections and not .init */ 1643 if (sechdrs[i].sh_type == SHT_RELA) 1644 section_rela(modname, elf, &elf->sechdrs[i]); 1645 else if (sechdrs[i].sh_type == SHT_REL) 1646 section_rel(modname, elf, &elf->sechdrs[i]); 1647 } 1648 } 1649 1650 static void read_symbols(char *modname) 1651 { 1652 const char *symname; 1653 char *version; 1654 char *license; 1655 struct module *mod; 1656 struct elf_info info = { }; 1657 Elf_Sym *sym; 1658 1659 if (!parse_elf(&info, modname)) 1660 return; 1661 1662 mod = new_module(modname); 1663 1664 /* When there's no vmlinux, don't print warnings about 1665 * unresolved symbols (since there'll be too many ;) */ 1666 if (is_vmlinux(modname)) { 1667 have_vmlinux = 1; 1668 mod->skip = 1; 1669 } 1670 1671 license = get_modinfo(info.modinfo, info.modinfo_len, "license"); 1672 if (info.modinfo && !license && !is_vmlinux(modname)) 1673 warn("modpost: missing MODULE_LICENSE() in %s\n" 1674 "see include/linux/module.h for " 1675 "more information\n", modname); 1676 while (license) { 1677 if (license_is_gpl_compatible(license)) 1678 mod->gpl_compatible = 1; 1679 else { 1680 mod->gpl_compatible = 0; 1681 break; 1682 } 1683 license = get_next_modinfo(info.modinfo, info.modinfo_len, 1684 "license", license); 1685 } 1686 1687 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { 1688 symname = info.strtab + sym->st_name; 1689 1690 handle_modversions(mod, &info, sym, symname); 1691 handle_moddevtable(mod, &info, sym, symname); 1692 } 1693 if (!is_vmlinux(modname) || 1694 (is_vmlinux(modname) && vmlinux_section_warnings)) 1695 check_sec_ref(mod, modname, &info); 1696 1697 version = get_modinfo(info.modinfo, info.modinfo_len, "version"); 1698 if (version) 1699 maybe_frob_rcs_version(modname, version, info.modinfo, 1700 version - (char *)info.hdr); 1701 if (version || (all_versions && !is_vmlinux(modname))) 1702 get_src_version(modname, mod->srcversion, 1703 sizeof(mod->srcversion)-1); 1704 1705 parse_elf_finish(&info); 1706 1707 /* Our trick to get versioning for module struct etc. - it's 1708 * never passed as an argument to an exported function, so 1709 * the automatic versioning doesn't pick it up, but it's really 1710 * important anyhow */ 1711 if (modversions) 1712 mod->unres = alloc_symbol("module_layout", 0, mod->unres); 1713 } 1714 1715 #define SZ 500 1716 1717 /* We first write the generated file into memory using the 1718 * following helper, then compare to the file on disk and 1719 * only update the later if anything changed */ 1720 1721 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf, 1722 const char *fmt, ...) 1723 { 1724 char tmp[SZ]; 1725 int len; 1726 va_list ap; 1727 1728 va_start(ap, fmt); 1729 len = vsnprintf(tmp, SZ, fmt, ap); 1730 buf_write(buf, tmp, len); 1731 va_end(ap); 1732 } 1733 1734 void buf_write(struct buffer *buf, const char *s, int len) 1735 { 1736 if (buf->size - buf->pos < len) { 1737 buf->size += len + SZ; 1738 buf->p = realloc(buf->p, buf->size); 1739 } 1740 strncpy(buf->p + buf->pos, s, len); 1741 buf->pos += len; 1742 } 1743 1744 static void check_for_gpl_usage(enum export exp, const char *m, const char *s) 1745 { 1746 const char *e = is_vmlinux(m) ?"":".ko"; 1747 1748 switch (exp) { 1749 case export_gpl: 1750 fatal("modpost: GPL-incompatible module %s%s " 1751 "uses GPL-only symbol '%s'\n", m, e, s); 1752 break; 1753 case export_unused_gpl: 1754 fatal("modpost: GPL-incompatible module %s%s " 1755 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s); 1756 break; 1757 case export_gpl_future: 1758 warn("modpost: GPL-incompatible module %s%s " 1759 "uses future GPL-only symbol '%s'\n", m, e, s); 1760 break; 1761 case export_plain: 1762 case export_unused: 1763 case export_unknown: 1764 /* ignore */ 1765 break; 1766 } 1767 } 1768 1769 static void check_for_unused(enum export exp, const char *m, const char *s) 1770 { 1771 const char *e = is_vmlinux(m) ?"":".ko"; 1772 1773 switch (exp) { 1774 case export_unused: 1775 case export_unused_gpl: 1776 warn("modpost: module %s%s " 1777 "uses symbol '%s' marked UNUSED\n", m, e, s); 1778 break; 1779 default: 1780 /* ignore */ 1781 break; 1782 } 1783 } 1784 1785 static void check_exports(struct module *mod) 1786 { 1787 struct symbol *s, *exp; 1788 1789 for (s = mod->unres; s; s = s->next) { 1790 const char *basename; 1791 exp = find_symbol(s->name); 1792 if (!exp || exp->module == mod) 1793 continue; 1794 basename = strrchr(mod->name, '/'); 1795 if (basename) 1796 basename++; 1797 else 1798 basename = mod->name; 1799 if (!mod->gpl_compatible) 1800 check_for_gpl_usage(exp->export, basename, exp->name); 1801 check_for_unused(exp->export, basename, exp->name); 1802 } 1803 } 1804 1805 /** 1806 * Header for the generated file 1807 **/ 1808 static void add_header(struct buffer *b, struct module *mod) 1809 { 1810 buf_printf(b, "#include <linux/module.h>\n"); 1811 buf_printf(b, "#include <linux/vermagic.h>\n"); 1812 buf_printf(b, "#include <linux/compiler.h>\n"); 1813 buf_printf(b, "\n"); 1814 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n"); 1815 buf_printf(b, "\n"); 1816 buf_printf(b, "struct module __this_module\n"); 1817 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n"); 1818 buf_printf(b, " .name = KBUILD_MODNAME,\n"); 1819 if (mod->has_init) 1820 buf_printf(b, " .init = init_module,\n"); 1821 if (mod->has_cleanup) 1822 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n" 1823 " .exit = cleanup_module,\n" 1824 "#endif\n"); 1825 buf_printf(b, " .arch = MODULE_ARCH_INIT,\n"); 1826 buf_printf(b, "};\n"); 1827 } 1828 1829 static void add_staging_flag(struct buffer *b, const char *name) 1830 { 1831 static const char *staging_dir = "drivers/staging"; 1832 1833 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0) 1834 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); 1835 } 1836 1837 /** 1838 * Record CRCs for unresolved symbols 1839 **/ 1840 static int add_versions(struct buffer *b, struct module *mod) 1841 { 1842 struct symbol *s, *exp; 1843 int err = 0; 1844 1845 for (s = mod->unres; s; s = s->next) { 1846 exp = find_symbol(s->name); 1847 if (!exp || exp->module == mod) { 1848 if (have_vmlinux && !s->weak) { 1849 if (warn_unresolved) { 1850 warn("\"%s\" [%s.ko] undefined!\n", 1851 s->name, mod->name); 1852 } else { 1853 merror("\"%s\" [%s.ko] undefined!\n", 1854 s->name, mod->name); 1855 err = 1; 1856 } 1857 } 1858 continue; 1859 } 1860 s->module = exp->module; 1861 s->crc_valid = exp->crc_valid; 1862 s->crc = exp->crc; 1863 } 1864 1865 if (!modversions) 1866 return err; 1867 1868 buf_printf(b, "\n"); 1869 buf_printf(b, "static const struct modversion_info ____versions[]\n"); 1870 buf_printf(b, "__used\n"); 1871 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n"); 1872 1873 for (s = mod->unres; s; s = s->next) { 1874 if (!s->module) 1875 continue; 1876 if (!s->crc_valid) { 1877 warn("\"%s\" [%s.ko] has no CRC!\n", 1878 s->name, mod->name); 1879 continue; 1880 } 1881 buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name); 1882 } 1883 1884 buf_printf(b, "};\n"); 1885 1886 return err; 1887 } 1888 1889 static void add_depends(struct buffer *b, struct module *mod, 1890 struct module *modules) 1891 { 1892 struct symbol *s; 1893 struct module *m; 1894 int first = 1; 1895 1896 for (m = modules; m; m = m->next) 1897 m->seen = is_vmlinux(m->name); 1898 1899 buf_printf(b, "\n"); 1900 buf_printf(b, "static const char __module_depends[]\n"); 1901 buf_printf(b, "__used\n"); 1902 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n"); 1903 buf_printf(b, "\"depends="); 1904 for (s = mod->unres; s; s = s->next) { 1905 const char *p; 1906 if (!s->module) 1907 continue; 1908 1909 if (s->module->seen) 1910 continue; 1911 1912 s->module->seen = 1; 1913 p = strrchr(s->module->name, '/'); 1914 if (p) 1915 p++; 1916 else 1917 p = s->module->name; 1918 buf_printf(b, "%s%s", first ? "" : ",", p); 1919 first = 0; 1920 } 1921 buf_printf(b, "\";\n"); 1922 } 1923 1924 static void add_srcversion(struct buffer *b, struct module *mod) 1925 { 1926 if (mod->srcversion[0]) { 1927 buf_printf(b, "\n"); 1928 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n", 1929 mod->srcversion); 1930 } 1931 } 1932 1933 static void write_if_changed(struct buffer *b, const char *fname) 1934 { 1935 char *tmp; 1936 FILE *file; 1937 struct stat st; 1938 1939 file = fopen(fname, "r"); 1940 if (!file) 1941 goto write; 1942 1943 if (fstat(fileno(file), &st) < 0) 1944 goto close_write; 1945 1946 if (st.st_size != b->pos) 1947 goto close_write; 1948 1949 tmp = NOFAIL(malloc(b->pos)); 1950 if (fread(tmp, 1, b->pos, file) != b->pos) 1951 goto free_write; 1952 1953 if (memcmp(tmp, b->p, b->pos) != 0) 1954 goto free_write; 1955 1956 free(tmp); 1957 fclose(file); 1958 return; 1959 1960 free_write: 1961 free(tmp); 1962 close_write: 1963 fclose(file); 1964 write: 1965 file = fopen(fname, "w"); 1966 if (!file) { 1967 perror(fname); 1968 exit(1); 1969 } 1970 if (fwrite(b->p, 1, b->pos, file) != b->pos) { 1971 perror(fname); 1972 exit(1); 1973 } 1974 fclose(file); 1975 } 1976 1977 /* parse Module.symvers file. line format: 1978 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something] 1979 **/ 1980 static void read_dump(const char *fname, unsigned int kernel) 1981 { 1982 unsigned long size, pos = 0; 1983 void *file = grab_file(fname, &size); 1984 char *line; 1985 1986 if (!file) 1987 /* No symbol versions, silently ignore */ 1988 return; 1989 1990 while ((line = get_next_line(&pos, file, size))) { 1991 char *symname, *modname, *d, *export, *end; 1992 unsigned int crc; 1993 struct module *mod; 1994 struct symbol *s; 1995 1996 if (!(symname = strchr(line, '\t'))) 1997 goto fail; 1998 *symname++ = '\0'; 1999 if (!(modname = strchr(symname, '\t'))) 2000 goto fail; 2001 *modname++ = '\0'; 2002 if ((export = strchr(modname, '\t')) != NULL) 2003 *export++ = '\0'; 2004 if (export && ((end = strchr(export, '\t')) != NULL)) 2005 *end = '\0'; 2006 crc = strtoul(line, &d, 16); 2007 if (*symname == '\0' || *modname == '\0' || *d != '\0') 2008 goto fail; 2009 mod = find_module(modname); 2010 if (!mod) { 2011 if (is_vmlinux(modname)) 2012 have_vmlinux = 1; 2013 mod = new_module(modname); 2014 mod->skip = 1; 2015 } 2016 s = sym_add_exported(symname, mod, export_no(export)); 2017 s->kernel = kernel; 2018 s->preloaded = 1; 2019 sym_update_crc(symname, mod, crc, export_no(export)); 2020 } 2021 return; 2022 fail: 2023 fatal("parse error in symbol dump file\n"); 2024 } 2025 2026 /* For normal builds always dump all symbols. 2027 * For external modules only dump symbols 2028 * that are not read from kernel Module.symvers. 2029 **/ 2030 static int dump_sym(struct symbol *sym) 2031 { 2032 if (!external_module) 2033 return 1; 2034 if (sym->vmlinux || sym->kernel) 2035 return 0; 2036 return 1; 2037 } 2038 2039 static void write_dump(const char *fname) 2040 { 2041 struct buffer buf = { }; 2042 struct symbol *symbol; 2043 int n; 2044 2045 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) { 2046 symbol = symbolhash[n]; 2047 while (symbol) { 2048 if (dump_sym(symbol)) 2049 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n", 2050 symbol->crc, symbol->name, 2051 symbol->module->name, 2052 export_str(symbol->export)); 2053 symbol = symbol->next; 2054 } 2055 } 2056 write_if_changed(&buf, fname); 2057 } 2058 2059 struct ext_sym_list { 2060 struct ext_sym_list *next; 2061 const char *file; 2062 }; 2063 2064 int main(int argc, char **argv) 2065 { 2066 struct module *mod; 2067 struct buffer buf = { }; 2068 char *kernel_read = NULL, *module_read = NULL; 2069 char *dump_write = NULL; 2070 int opt; 2071 int err; 2072 struct ext_sym_list *extsym_iter; 2073 struct ext_sym_list *extsym_start = NULL; 2074 2075 while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) { 2076 switch (opt) { 2077 case 'i': 2078 kernel_read = optarg; 2079 break; 2080 case 'I': 2081 module_read = optarg; 2082 external_module = 1; 2083 break; 2084 case 'c': 2085 cross_build = 1; 2086 break; 2087 case 'e': 2088 external_module = 1; 2089 extsym_iter = 2090 NOFAIL(malloc(sizeof(*extsym_iter))); 2091 extsym_iter->next = extsym_start; 2092 extsym_iter->file = optarg; 2093 extsym_start = extsym_iter; 2094 break; 2095 case 'm': 2096 modversions = 1; 2097 break; 2098 case 'o': 2099 dump_write = optarg; 2100 break; 2101 case 'a': 2102 all_versions = 1; 2103 break; 2104 case 's': 2105 vmlinux_section_warnings = 0; 2106 break; 2107 case 'S': 2108 sec_mismatch_verbose = 0; 2109 break; 2110 case 'w': 2111 warn_unresolved = 1; 2112 break; 2113 default: 2114 exit(1); 2115 } 2116 } 2117 2118 if (kernel_read) 2119 read_dump(kernel_read, 1); 2120 if (module_read) 2121 read_dump(module_read, 0); 2122 while (extsym_start) { 2123 read_dump(extsym_start->file, 0); 2124 extsym_iter = extsym_start->next; 2125 free(extsym_start); 2126 extsym_start = extsym_iter; 2127 } 2128 2129 while (optind < argc) 2130 read_symbols(argv[optind++]); 2131 2132 for (mod = modules; mod; mod = mod->next) { 2133 if (mod->skip) 2134 continue; 2135 check_exports(mod); 2136 } 2137 2138 err = 0; 2139 2140 for (mod = modules; mod; mod = mod->next) { 2141 char fname[strlen(mod->name) + 10]; 2142 2143 if (mod->skip) 2144 continue; 2145 2146 buf.pos = 0; 2147 2148 add_header(&buf, mod); 2149 add_staging_flag(&buf, mod->name); 2150 err |= add_versions(&buf, mod); 2151 add_depends(&buf, mod, modules); 2152 add_moddevtable(&buf, mod); 2153 add_srcversion(&buf, mod); 2154 2155 sprintf(fname, "%s.mod.c", mod->name); 2156 write_if_changed(&buf, fname); 2157 } 2158 2159 if (dump_write) 2160 write_dump(dump_write); 2161 if (sec_mismatch_count && !sec_mismatch_verbose) 2162 warn("modpost: Found %d section mismatch(es).\n" 2163 "To see full details build your kernel with:\n" 2164 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n", 2165 sec_mismatch_count); 2166 2167 return err; 2168 } 2169