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? */ 31int modversions = 0; 32/* Warn about undefined symbols? (do so if we have vmlinux) */ 33int have_vmlinux = 0; 34/* Is CONFIG_MODULE_SRCVERSION_ALL set? */ 35static int all_versions = 0; 36/* If we are modposting external module set to 1 */ 37static int external_module = 0; 38/* Warn about section mismatch in vmlinux if set to 1 */ 39static int vmlinux_section_warnings = 1; 40/* Only warn about unresolved symbols */ 41static int warn_unresolved = 0; 42/* How a symbol is exported */ 43static int sec_mismatch_count = 0; 44static int sec_mismatch_verbose = 1; 45 46enum 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 53PRINTF 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 66PRINTF 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 77PRINTF 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 88static 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 102void *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 */ 111static struct module *modules; 112 113static 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 123static 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 mod->is_dot_o = 1; 138 } 139 140 /* add to list */ 141 mod->name = p; 142 mod->gpl_compatible = -1; 143 mod->next = modules; 144 modules = mod; 145 146 return mod; 147} 148 149/* A hash of all exported symbols, 150 * struct symbol is also used for lists of unresolved symbols */ 151 152#define SYMBOL_HASH_SIZE 1024 153 154struct symbol { 155 struct symbol *next; 156 struct module *module; 157 unsigned int crc; 158 int crc_valid; 159 unsigned int weak:1; 160 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */ 161 unsigned int kernel:1; /* 1 if symbol is from kernel 162 * (only for external modules) **/ 163 unsigned int preloaded:1; /* 1 if symbol from Module.symvers */ 164 enum export export; /* Type of export */ 165 char name[0]; 166}; 167 168static struct symbol *symbolhash[SYMBOL_HASH_SIZE]; 169 170/* This is based on the hash agorithm from gdbm, via tdb */ 171static inline unsigned int tdb_hash(const char *name) 172{ 173 unsigned value; /* Used to compute the hash value. */ 174 unsigned i; /* Used to cycle through random values. */ 175 176 /* Set the initial value from the key size. */ 177 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++) 178 value = (value + (((unsigned char *)name)[i] << (i*5 % 24))); 179 180 return (1103515243 * value + 12345); 181} 182 183/** 184 * Allocate a new symbols for use in the hash of exported symbols or 185 * the list of unresolved symbols per module 186 **/ 187static struct symbol *alloc_symbol(const char *name, unsigned int weak, 188 struct symbol *next) 189{ 190 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1)); 191 192 memset(s, 0, sizeof(*s)); 193 strcpy(s->name, name); 194 s->weak = weak; 195 s->next = next; 196 return s; 197} 198 199/* For the hash of exported symbols */ 200static struct symbol *new_symbol(const char *name, struct module *module, 201 enum export export) 202{ 203 unsigned int hash; 204 struct symbol *new; 205 206 hash = tdb_hash(name) % SYMBOL_HASH_SIZE; 207 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]); 208 new->module = module; 209 new->export = export; 210 return new; 211} 212 213static struct symbol *find_symbol(const char *name) 214{ 215 struct symbol *s; 216 217 /* For our purposes, .foo matches foo. PPC64 needs this. */ 218 if (name[0] == '.') 219 name++; 220 221 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) { 222 if (strcmp(s->name, name) == 0) 223 return s; 224 } 225 return NULL; 226} 227 228static struct { 229 const char *str; 230 enum export export; 231} export_list[] = { 232 { .str = "EXPORT_SYMBOL", .export = export_plain }, 233 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused }, 234 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl }, 235 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl }, 236 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future }, 237 { .str = "(unknown)", .export = export_unknown }, 238}; 239 240 241static const char *export_str(enum export ex) 242{ 243 return export_list[ex].str; 244} 245 246static enum export export_no(const char *s) 247{ 248 int i; 249 250 if (!s) 251 return export_unknown; 252 for (i = 0; export_list[i].export != export_unknown; i++) { 253 if (strcmp(export_list[i].str, s) == 0) 254 return export_list[i].export; 255 } 256 return export_unknown; 257} 258 259static const char *sec_name(struct elf_info *elf, int secindex); 260 261#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0) 262 263static enum export export_from_secname(struct elf_info *elf, unsigned int sec) 264{ 265 const char *secname = sec_name(elf, sec); 266 267 if (strstarts(secname, "___ksymtab+")) 268 return export_plain; 269 else if (strstarts(secname, "___ksymtab_unused+")) 270 return export_unused; 271 else if (strstarts(secname, "___ksymtab_gpl+")) 272 return export_gpl; 273 else if (strstarts(secname, "___ksymtab_unused_gpl+")) 274 return export_unused_gpl; 275 else if (strstarts(secname, "___ksymtab_gpl_future+")) 276 return export_gpl_future; 277 else 278 return export_unknown; 279} 280 281static enum export export_from_sec(struct elf_info *elf, unsigned int sec) 282{ 283 if (sec == elf->export_sec) 284 return export_plain; 285 else if (sec == elf->export_unused_sec) 286 return export_unused; 287 else if (sec == elf->export_gpl_sec) 288 return export_gpl; 289 else if (sec == elf->export_unused_gpl_sec) 290 return export_unused_gpl; 291 else if (sec == elf->export_gpl_future_sec) 292 return export_gpl_future; 293 else 294 return export_unknown; 295} 296 297/** 298 * Add an exported symbol - it may have already been added without a 299 * CRC, in this case just update the CRC 300 **/ 301static struct symbol *sym_add_exported(const char *name, struct module *mod, 302 enum export export) 303{ 304 struct symbol *s = find_symbol(name); 305 306 if (!s) { 307 s = new_symbol(name, mod, export); 308 } else { 309 if (!s->preloaded) { 310 warn("%s: '%s' exported twice. Previous export " 311 "was in %s%s\n", mod->name, name, 312 s->module->name, 313 is_vmlinux(s->module->name) ?"":".ko"); 314 } else { 315 /* In case Modules.symvers was out of date */ 316 s->module = mod; 317 } 318 } 319 s->preloaded = 0; 320 s->vmlinux = is_vmlinux(mod->name); 321 s->kernel = 0; 322 s->export = export; 323 return s; 324} 325 326static void sym_update_crc(const char *name, struct module *mod, 327 unsigned int crc, enum export export) 328{ 329 struct symbol *s = find_symbol(name); 330 331 if (!s) 332 s = new_symbol(name, mod, export); 333 s->crc = crc; 334 s->crc_valid = 1; 335} 336 337void *grab_file(const char *filename, unsigned long *size) 338{ 339 struct stat st; 340 void *map; 341 int fd; 342 343 fd = open(filename, O_RDONLY); 344 if (fd < 0 || fstat(fd, &st) != 0) 345 return NULL; 346 347 *size = st.st_size; 348 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); 349 close(fd); 350 351 if (map == MAP_FAILED) 352 return NULL; 353 return map; 354} 355 356/** 357 * Return a copy of the next line in a mmap'ed file. 358 * spaces in the beginning of the line is trimmed away. 359 * Return a pointer to a static buffer. 360 **/ 361char *get_next_line(unsigned long *pos, void *file, unsigned long size) 362{ 363 static char line[4096]; 364 int skip = 1; 365 size_t len = 0; 366 signed char *p = (signed char *)file + *pos; 367 char *s = line; 368 369 for (; *pos < size ; (*pos)++) { 370 if (skip && isspace(*p)) { 371 p++; 372 continue; 373 } 374 skip = 0; 375 if (*p != '\n' && (*pos < size)) { 376 len++; 377 *s++ = *p++; 378 if (len > 4095) 379 break; /* Too long, stop */ 380 } else { 381 /* End of string */ 382 *s = '\0'; 383 return line; 384 } 385 } 386 /* End of buffer */ 387 return NULL; 388} 389 390void release_file(void *file, unsigned long size) 391{ 392 munmap(file, size); 393} 394 395static int parse_elf(struct elf_info *info, const char *filename) 396{ 397 unsigned int i; 398 Elf_Ehdr *hdr; 399 Elf_Shdr *sechdrs; 400 Elf_Sym *sym; 401 const char *secstrings; 402 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U; 403 404 hdr = grab_file(filename, &info->size); 405 if (!hdr) { 406 perror(filename); 407 exit(1); 408 } 409 info->hdr = hdr; 410 if (info->size < sizeof(*hdr)) { 411 /* file too small, assume this is an empty .o file */ 412 return 0; 413 } 414 /* Is this a valid ELF file? */ 415 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) || 416 (hdr->e_ident[EI_MAG1] != ELFMAG1) || 417 (hdr->e_ident[EI_MAG2] != ELFMAG2) || 418 (hdr->e_ident[EI_MAG3] != ELFMAG3)) { 419 /* Not an ELF file - silently ignore it */ 420 return 0; 421 } 422 /* Fix endianness in ELF header */ 423 hdr->e_type = TO_NATIVE(hdr->e_type); 424 hdr->e_machine = TO_NATIVE(hdr->e_machine); 425 hdr->e_version = TO_NATIVE(hdr->e_version); 426 hdr->e_entry = TO_NATIVE(hdr->e_entry); 427 hdr->e_phoff = TO_NATIVE(hdr->e_phoff); 428 hdr->e_shoff = TO_NATIVE(hdr->e_shoff); 429 hdr->e_flags = TO_NATIVE(hdr->e_flags); 430 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize); 431 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize); 432 hdr->e_phnum = TO_NATIVE(hdr->e_phnum); 433 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize); 434 hdr->e_shnum = TO_NATIVE(hdr->e_shnum); 435 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx); 436 sechdrs = (void *)hdr + hdr->e_shoff; 437 info->sechdrs = sechdrs; 438 439 /* Check if file offset is correct */ 440 if (hdr->e_shoff > info->size) { 441 fatal("section header offset=%lu in file '%s' is bigger than " 442 "filesize=%lu\n", (unsigned long)hdr->e_shoff, 443 filename, info->size); 444 return 0; 445 } 446 447 if (hdr->e_shnum == SHN_UNDEF) { 448 /* 449 * There are more than 64k sections, 450 * read count from .sh_size. 451 */ 452 info->num_sections = TO_NATIVE(sechdrs[0].sh_size); 453 } 454 else { 455 info->num_sections = hdr->e_shnum; 456 } 457 if (hdr->e_shstrndx == SHN_XINDEX) { 458 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link); 459 } 460 else { 461 info->secindex_strings = hdr->e_shstrndx; 462 } 463 464 /* Fix endianness in section headers */ 465 for (i = 0; i < info->num_sections; i++) { 466 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name); 467 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); 468 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags); 469 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr); 470 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset); 471 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size); 472 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link); 473 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info); 474 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign); 475 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize); 476 } 477 /* Find symbol table. */ 478 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset; 479 for (i = 1; i < info->num_sections; i++) { 480 const char *secname; 481 int nobits = sechdrs[i].sh_type == SHT_NOBITS; 482 483 if (!nobits && sechdrs[i].sh_offset > info->size) { 484 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > " 485 "sizeof(*hrd)=%zu\n", filename, 486 (unsigned long)sechdrs[i].sh_offset, 487 sizeof(*hdr)); 488 return 0; 489 } 490 secname = secstrings + sechdrs[i].sh_name; 491 if (strcmp(secname, ".modinfo") == 0) { 492 if (nobits) 493 fatal("%s has NOBITS .modinfo\n", filename); 494 info->modinfo = (void *)hdr + sechdrs[i].sh_offset; 495 info->modinfo_len = sechdrs[i].sh_size; 496 } else if (strcmp(secname, "__ksymtab") == 0) 497 info->export_sec = i; 498 else if (strcmp(secname, "__ksymtab_unused") == 0) 499 info->export_unused_sec = i; 500 else if (strcmp(secname, "__ksymtab_gpl") == 0) 501 info->export_gpl_sec = i; 502 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0) 503 info->export_unused_gpl_sec = i; 504 else if (strcmp(secname, "__ksymtab_gpl_future") == 0) 505 info->export_gpl_future_sec = i; 506 507 if (sechdrs[i].sh_type == SHT_SYMTAB) { 508 unsigned int sh_link_idx; 509 symtab_idx = i; 510 info->symtab_start = (void *)hdr + 511 sechdrs[i].sh_offset; 512 info->symtab_stop = (void *)hdr + 513 sechdrs[i].sh_offset + sechdrs[i].sh_size; 514 sh_link_idx = sechdrs[i].sh_link; 515 info->strtab = (void *)hdr + 516 sechdrs[sh_link_idx].sh_offset; 517 } 518 519 /* 32bit section no. table? ("more than 64k sections") */ 520 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) { 521 symtab_shndx_idx = i; 522 info->symtab_shndx_start = (void *)hdr + 523 sechdrs[i].sh_offset; 524 info->symtab_shndx_stop = (void *)hdr + 525 sechdrs[i].sh_offset + sechdrs[i].sh_size; 526 } 527 } 528 if (!info->symtab_start) 529 fatal("%s has no symtab?\n", filename); 530 531 /* Fix endianness in symbols */ 532 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) { 533 sym->st_shndx = TO_NATIVE(sym->st_shndx); 534 sym->st_name = TO_NATIVE(sym->st_name); 535 sym->st_value = TO_NATIVE(sym->st_value); 536 sym->st_size = TO_NATIVE(sym->st_size); 537 } 538 539 if (symtab_shndx_idx != ~0U) { 540 Elf32_Word *p; 541 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link) 542 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n", 543 filename, sechdrs[symtab_shndx_idx].sh_link, 544 symtab_idx); 545 /* Fix endianness */ 546 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop; 547 p++) 548 *p = TO_NATIVE(*p); 549 } 550 551 return 1; 552} 553 554static void parse_elf_finish(struct elf_info *info) 555{ 556 release_file(info->hdr, info->size); 557} 558 559static int ignore_undef_symbol(struct elf_info *info, const char *symname) 560{ 561 /* ignore __this_module, it will be resolved shortly */ 562 if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0) 563 return 1; 564 /* ignore global offset table */ 565 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0) 566 return 1; 567 if (info->hdr->e_machine == EM_PPC) 568 /* Special register function linked on all modules during final link of .ko */ 569 if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 || 570 strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 || 571 strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 || 572 strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0) 573 return 1; 574 if (info->hdr->e_machine == EM_PPC64) 575 /* Special register function linked on all modules during final link of .ko */ 576 if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 || 577 strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0) 578 return 1; 579 /* Do not ignore this symbol */ 580 return 0; 581} 582 583#define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_" 584#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_" 585 586static void handle_modversions(struct module *mod, struct elf_info *info, 587 Elf_Sym *sym, const char *symname) 588{ 589 unsigned int crc; 590 enum export export; 591 592 if ((!is_vmlinux(mod->name) || mod->is_dot_o) && 593 strncmp(symname, "__ksymtab", 9) == 0) 594 export = export_from_secname(info, get_secindex(info, sym)); 595 else 596 export = export_from_sec(info, get_secindex(info, sym)); 597 598 switch (sym->st_shndx) { 599 case SHN_COMMON: 600 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name); 601 break; 602 case SHN_ABS: 603 /* CRC'd symbol */ 604 if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) { 605 crc = (unsigned int) sym->st_value; 606 sym_update_crc(symname + strlen(CRC_PFX), mod, crc, 607 export); 608 } 609 break; 610 case SHN_UNDEF: 611 /* undefined symbol */ 612 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 613 ELF_ST_BIND(sym->st_info) != STB_WEAK) 614 break; 615 if (ignore_undef_symbol(info, symname)) 616 break; 617/* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */ 618#if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER) 619/* add compatibility with older glibc */ 620#ifndef STT_SPARC_REGISTER 621#define STT_SPARC_REGISTER STT_REGISTER 622#endif 623 if (info->hdr->e_machine == EM_SPARC || 624 info->hdr->e_machine == EM_SPARCV9) { 625 /* Ignore register directives. */ 626 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER) 627 break; 628 if (symname[0] == '.') { 629 char *munged = strdup(symname); 630 munged[0] = '_'; 631 munged[1] = toupper(munged[1]); 632 symname = munged; 633 } 634 } 635#endif 636 637 if (memcmp(symname, MODULE_SYMBOL_PREFIX, 638 strlen(MODULE_SYMBOL_PREFIX)) == 0) { 639 mod->unres = 640 alloc_symbol(symname + 641 strlen(MODULE_SYMBOL_PREFIX), 642 ELF_ST_BIND(sym->st_info) == STB_WEAK, 643 mod->unres); 644 } 645 break; 646 default: 647 /* All exported symbols */ 648 if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) { 649 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod, 650 export); 651 } 652 if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0) 653 mod->has_init = 1; 654 if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0) 655 mod->has_cleanup = 1; 656 break; 657 } 658} 659 660/** 661 * Parse tag=value strings from .modinfo section 662 **/ 663static char *next_string(char *string, unsigned long *secsize) 664{ 665 /* Skip non-zero chars */ 666 while (string[0]) { 667 string++; 668 if ((*secsize)-- <= 1) 669 return NULL; 670 } 671 672 /* Skip any zero padding. */ 673 while (!string[0]) { 674 string++; 675 if ((*secsize)-- <= 1) 676 return NULL; 677 } 678 return string; 679} 680 681static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len, 682 const char *tag, char *info) 683{ 684 char *p; 685 unsigned int taglen = strlen(tag); 686 unsigned long size = modinfo_len; 687 688 if (info) { 689 size -= info - (char *)modinfo; 690 modinfo = next_string(info, &size); 691 } 692 693 for (p = modinfo; p; p = next_string(p, &size)) { 694 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') 695 return p + taglen + 1; 696 } 697 return NULL; 698} 699 700static char *get_modinfo(void *modinfo, unsigned long modinfo_len, 701 const char *tag) 702 703{ 704 return get_next_modinfo(modinfo, modinfo_len, tag, NULL); 705} 706 707/** 708 * Test if string s ends in string sub 709 * return 0 if match 710 **/ 711static int strrcmp(const char *s, const char *sub) 712{ 713 int slen, sublen; 714 715 if (!s || !sub) 716 return 1; 717 718 slen = strlen(s); 719 sublen = strlen(sub); 720 721 if ((slen == 0) || (sublen == 0)) 722 return 1; 723 724 if (sublen > slen) 725 return 1; 726 727 return memcmp(s + slen - sublen, sub, sublen); 728} 729 730static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) 731{ 732 if (sym) 733 return elf->strtab + sym->st_name; 734 else 735 return "(unknown)"; 736} 737 738static const char *sec_name(struct elf_info *elf, int secindex) 739{ 740 Elf_Shdr *sechdrs = elf->sechdrs; 741 return (void *)elf->hdr + 742 elf->sechdrs[elf->secindex_strings].sh_offset + 743 sechdrs[secindex].sh_name; 744} 745 746static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr) 747{ 748 return (void *)elf->hdr + 749 elf->sechdrs[elf->secindex_strings].sh_offset + 750 sechdr->sh_name; 751} 752 753/* if sym is empty or point to a string 754 * like ".[0-9]+" then return 1. 755 * This is the optional prefix added by ld to some sections 756 */ 757static int number_prefix(const char *sym) 758{ 759 if (*sym++ == '\0') 760 return 1; 761 if (*sym != '.') 762 return 0; 763 do { 764 char c = *sym++; 765 if (c < '0' || c > '9') 766 return 0; 767 } while (*sym); 768 return 1; 769} 770 771/* The pattern is an array of simple patterns. 772 * "foo" will match an exact string equal to "foo" 773 * "*foo" will match a string that ends with "foo" 774 * "foo*" will match a string that begins with "foo" 775 * "foo$" will match a string equal to "foo" or "foo.1" 776 * where the '1' can be any number including several digits. 777 * The $ syntax is for sections where ld append a dot number 778 * to make section name unique. 779 */ 780static int match(const char *sym, const char * const pat[]) 781{ 782 const char *p; 783 while (*pat) { 784 p = *pat++; 785 const char *endp = p + strlen(p) - 1; 786 787 /* "*foo" */ 788 if (*p == '*') { 789 if (strrcmp(sym, p + 1) == 0) 790 return 1; 791 } 792 /* "foo*" */ 793 else if (*endp == '*') { 794 if (strncmp(sym, p, strlen(p) - 1) == 0) 795 return 1; 796 } 797 /* "foo$" */ 798 else if (*endp == '$') { 799 if (strncmp(sym, p, strlen(p) - 1) == 0) { 800 if (number_prefix(sym + strlen(p) - 1)) 801 return 1; 802 } 803 } 804 /* no wildcards */ 805 else { 806 if (strcmp(p, sym) == 0) 807 return 1; 808 } 809 } 810 /* no match */ 811 return 0; 812} 813 814/* sections that we do not want to do full section mismatch check on */ 815static const char *section_white_list[] = 816{ 817 ".comment*", 818 ".debug*", 819 ".zdebug*", /* Compressed debug sections. */ 820 ".GCC-command-line", /* mn10300 */ 821 ".mdebug*", /* alpha, score, mips etc. */ 822 ".pdr", /* alpha, score, mips etc. */ 823 ".stab*", 824 ".note*", 825 ".got*", 826 ".toc*", 827 NULL 828}; 829 830/* 831 * This is used to find sections missing the SHF_ALLOC flag. 832 * The cause of this is often a section specified in assembler 833 * without "ax" / "aw". 834 */ 835static void check_section(const char *modname, struct elf_info *elf, 836 Elf_Shdr *sechdr) 837{ 838 const char *sec = sech_name(elf, sechdr); 839 840 if (sechdr->sh_type == SHT_PROGBITS && 841 !(sechdr->sh_flags & SHF_ALLOC) && 842 !match(sec, section_white_list)) { 843 warn("%s (%s): unexpected non-allocatable section.\n" 844 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n" 845 "Note that for example <linux/init.h> contains\n" 846 "section definitions for use in .S files.\n\n", 847 modname, sec); 848 } 849} 850 851 852 853#define ALL_INIT_DATA_SECTIONS \ 854 ".init.setup$", ".init.rodata$", \ 855 ".devinit.rodata$", ".cpuinit.rodata$", ".meminit.rodata$", \ 856 ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$" 857#define ALL_EXIT_DATA_SECTIONS \ 858 ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$" 859 860#define ALL_INIT_TEXT_SECTIONS \ 861 ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$" 862#define ALL_EXIT_TEXT_SECTIONS \ 863 ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$" 864 865#define ALL_XXXINIT_SECTIONS DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, \ 866 MEM_INIT_SECTIONS 867#define ALL_XXXEXIT_SECTIONS DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, \ 868 MEM_EXIT_SECTIONS 869 870#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS 871#define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS 872 873#define DATA_SECTIONS ".data$", ".data.rel$" 874#define TEXT_SECTIONS ".text$" 875 876#define INIT_SECTIONS ".init.*" 877#define DEV_INIT_SECTIONS ".devinit.*" 878#define CPU_INIT_SECTIONS ".cpuinit.*" 879#define MEM_INIT_SECTIONS ".meminit.*" 880 881#define EXIT_SECTIONS ".exit.*" 882#define DEV_EXIT_SECTIONS ".devexit.*" 883#define CPU_EXIT_SECTIONS ".cpuexit.*" 884#define MEM_EXIT_SECTIONS ".memexit.*" 885 886/* init data sections */ 887static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL }; 888 889/* all init sections */ 890static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL }; 891 892/* All init and exit sections (code + data) */ 893static const char *init_exit_sections[] = 894 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }; 895 896/* data section */ 897static const char *data_sections[] = { DATA_SECTIONS, NULL }; 898 899 900/* symbols in .data that may refer to init/exit sections */ 901#define DEFAULT_SYMBOL_WHITE_LIST \ 902 "*driver", \ 903 "*_template", /* scsi uses *_template a lot */ \ 904 "*_timer", /* arm uses ops structures named _timer a lot */ \ 905 "*_sht", /* scsi also used *_sht to some extent */ \ 906 "*_ops", \ 907 "*_probe", \ 908 "*_probe_one", \ 909 "*_console" 910 911static const char *head_sections[] = { ".head.text*", NULL }; 912static const char *linker_symbols[] = 913 { "__init_begin", "_sinittext", "_einittext", NULL }; 914 915enum mismatch { 916 TEXT_TO_ANY_INIT, 917 DATA_TO_ANY_INIT, 918 TEXT_TO_ANY_EXIT, 919 DATA_TO_ANY_EXIT, 920 XXXINIT_TO_SOME_INIT, 921 XXXEXIT_TO_SOME_EXIT, 922 ANY_INIT_TO_ANY_EXIT, 923 ANY_EXIT_TO_ANY_INIT, 924 EXPORT_TO_INIT_EXIT, 925}; 926 927struct sectioncheck { 928 const char *fromsec[20]; 929 const char *tosec[20]; 930 enum mismatch mismatch; 931 const char *symbol_white_list[20]; 932}; 933 934const struct sectioncheck sectioncheck[] = { 935/* Do not reference init/exit code/data from 936 * normal code and data 937 */ 938{ 939 .fromsec = { TEXT_SECTIONS, NULL }, 940 .tosec = { ALL_INIT_SECTIONS, NULL }, 941 .mismatch = TEXT_TO_ANY_INIT, 942 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 943}, 944{ 945 .fromsec = { DATA_SECTIONS, NULL }, 946 .tosec = { ALL_XXXINIT_SECTIONS, NULL }, 947 .mismatch = DATA_TO_ANY_INIT, 948 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 949}, 950{ 951 .fromsec = { DATA_SECTIONS, NULL }, 952 .tosec = { INIT_SECTIONS, NULL }, 953 .mismatch = DATA_TO_ANY_INIT, 954 .symbol_white_list = { 955 "*_template", "*_timer", "*_sht", "*_ops", 956 "*_probe", "*_probe_one", "*_console", NULL 957 }, 958}, 959{ 960 .fromsec = { TEXT_SECTIONS, NULL }, 961 .tosec = { ALL_EXIT_SECTIONS, NULL }, 962 .mismatch = TEXT_TO_ANY_EXIT, 963 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 964}, 965{ 966 .fromsec = { DATA_SECTIONS, NULL }, 967 .tosec = { ALL_EXIT_SECTIONS, NULL }, 968 .mismatch = DATA_TO_ANY_EXIT, 969 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 970}, 971/* Do not reference init code/data from devinit/cpuinit/meminit code/data */ 972{ 973 .fromsec = { ALL_XXXINIT_SECTIONS, NULL }, 974 .tosec = { INIT_SECTIONS, NULL }, 975 .mismatch = XXXINIT_TO_SOME_INIT, 976 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 977}, 978/* Do not reference cpuinit code/data from meminit code/data */ 979{ 980 .fromsec = { MEM_INIT_SECTIONS, NULL }, 981 .tosec = { CPU_INIT_SECTIONS, NULL }, 982 .mismatch = XXXINIT_TO_SOME_INIT, 983 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 984}, 985/* Do not reference meminit code/data from cpuinit code/data */ 986{ 987 .fromsec = { CPU_INIT_SECTIONS, NULL }, 988 .tosec = { MEM_INIT_SECTIONS, NULL }, 989 .mismatch = XXXINIT_TO_SOME_INIT, 990 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 991}, 992/* Do not reference exit code/data from devexit/cpuexit/memexit code/data */ 993{ 994 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL }, 995 .tosec = { EXIT_SECTIONS, NULL }, 996 .mismatch = XXXEXIT_TO_SOME_EXIT, 997 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 998}, 999/* Do not reference cpuexit code/data from memexit code/data */ 1000{ 1001 .fromsec = { MEM_EXIT_SECTIONS, NULL }, 1002 .tosec = { CPU_EXIT_SECTIONS, NULL }, 1003 .mismatch = XXXEXIT_TO_SOME_EXIT, 1004 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 1005}, 1006/* Do not reference memexit code/data from cpuexit code/data */ 1007{ 1008 .fromsec = { CPU_EXIT_SECTIONS, NULL }, 1009 .tosec = { MEM_EXIT_SECTIONS, NULL }, 1010 .mismatch = XXXEXIT_TO_SOME_EXIT, 1011 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 1012}, 1013/* Do not use exit code/data from init code */ 1014{ 1015 .fromsec = { ALL_INIT_SECTIONS, NULL }, 1016 .tosec = { ALL_EXIT_SECTIONS, NULL }, 1017 .mismatch = ANY_INIT_TO_ANY_EXIT, 1018 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 1019}, 1020/* Do not use init code/data from exit code */ 1021{ 1022 .fromsec = { ALL_EXIT_SECTIONS, NULL }, 1023 .tosec = { ALL_INIT_SECTIONS, NULL }, 1024 .mismatch = ANY_EXIT_TO_ANY_INIT, 1025 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 1026}, 1027/* Do not export init/exit functions or data */ 1028{ 1029 .fromsec = { "__ksymtab*", NULL }, 1030 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL }, 1031 .mismatch = EXPORT_TO_INIT_EXIT, 1032 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 1033} 1034}; 1035 1036static const struct sectioncheck *section_mismatch( 1037 const char *fromsec, const char *tosec) 1038{ 1039 int i; 1040 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck); 1041 const struct sectioncheck *check = §ioncheck[0]; 1042 1043 for (i = 0; i < elems; i++) { 1044 if (match(fromsec, check->fromsec) && 1045 match(tosec, check->tosec)) 1046 return check; 1047 check++; 1048 } 1049 return NULL; 1050} 1051 1052/** 1053 * Whitelist to allow certain references to pass with no warning. 1054 * 1055 * Pattern 1: 1056 * If a module parameter is declared __initdata and permissions=0 1057 * then this is legal despite the warning generated. 1058 * We cannot see value of permissions here, so just ignore 1059 * this pattern. 1060 * The pattern is identified by: 1061 * tosec = .init.data 1062 * fromsec = .data* 1063 * atsym =__param* 1064 * 1065 * Pattern 1a: 1066 * module_param_call() ops can refer to __init set function if permissions=0 1067 * The pattern is identified by: 1068 * tosec = .init.text 1069 * fromsec = .data* 1070 * atsym = __param_ops_* 1071 * 1072 * Pattern 2: 1073 * Many drivers utilise a *driver container with references to 1074 * add, remove, probe functions etc. 1075 * These functions may often be marked __devinit and we do not want to 1076 * warn here. 1077 * the pattern is identified by: 1078 * tosec = init or exit section 1079 * fromsec = data section 1080 * atsym = *driver, *_template, *_sht, *_ops, *_probe, 1081 * *probe_one, *_console, *_timer 1082 * 1083 * Pattern 3: 1084 * Whitelist all references from .head.text to any init section 1085 * 1086 * Pattern 4: 1087 * Some symbols belong to init section but still it is ok to reference 1088 * these from non-init sections as these symbols don't have any memory 1089 * allocated for them and symbol address and value are same. So even 1090 * if init section is freed, its ok to reference those symbols. 1091 * For ex. symbols marking the init section boundaries. 1092 * This pattern is identified by 1093 * refsymname = __init_begin, _sinittext, _einittext 1094 * 1095 **/ 1096static int secref_whitelist(const struct sectioncheck *mismatch, 1097 const char *fromsec, const char *fromsym, 1098 const char *tosec, const char *tosym) 1099{ 1100 /* Check for pattern 1 */ 1101 if (match(tosec, init_data_sections) && 1102 match(fromsec, data_sections) && 1103 (strncmp(fromsym, "__param", strlen("__param")) == 0)) 1104 return 0; 1105 1106 /* Check for pattern 1a */ 1107 if (strcmp(tosec, ".init.text") == 0 && 1108 match(fromsec, data_sections) && 1109 (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0)) 1110 return 0; 1111 1112 /* Check for pattern 2 */ 1113 if (match(tosec, init_exit_sections) && 1114 match(fromsec, data_sections) && 1115 match(fromsym, mismatch->symbol_white_list)) 1116 return 0; 1117 1118 /* Check for pattern 3 */ 1119 if (match(fromsec, head_sections) && 1120 match(tosec, init_sections)) 1121 return 0; 1122 1123 /* Check for pattern 4 */ 1124 if (match(tosym, linker_symbols)) 1125 return 0; 1126 1127 return 1; 1128} 1129 1130/** 1131 * Find symbol based on relocation record info. 1132 * In some cases the symbol supplied is a valid symbol so 1133 * return refsym. If st_name != 0 we assume this is a valid symbol. 1134 * In other cases the symbol needs to be looked up in the symbol table 1135 * based on section and address. 1136 * **/ 1137static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr, 1138 Elf_Sym *relsym) 1139{ 1140 Elf_Sym *sym; 1141 Elf_Sym *near = NULL; 1142 Elf64_Sword distance = 20; 1143 Elf64_Sword d; 1144 unsigned int relsym_secindex; 1145 1146 if (relsym->st_name != 0) 1147 return relsym; 1148 1149 relsym_secindex = get_secindex(elf, relsym); 1150 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { 1151 if (get_secindex(elf, sym) != relsym_secindex) 1152 continue; 1153 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION) 1154 continue; 1155 if (sym->st_value == addr) 1156 return sym; 1157 /* Find a symbol nearby - addr are maybe negative */ 1158 d = sym->st_value - addr; 1159 if (d < 0) 1160 d = addr - sym->st_value; 1161 if (d < distance) { 1162 distance = d; 1163 near = sym; 1164 } 1165 } 1166 /* We need a close match */ 1167 if (distance < 20) 1168 return near; 1169 else 1170 return NULL; 1171} 1172 1173static inline int is_arm_mapping_symbol(const char *str) 1174{ 1175 return str[0] == '$' && strchr("atd", str[1]) 1176 && (str[2] == '\0' || str[2] == '.'); 1177} 1178 1179/* 1180 * If there's no name there, ignore it; likewise, ignore it if it's 1181 * one of the magic symbols emitted used by current ARM tools. 1182 * 1183 * Otherwise if find_symbols_between() returns those symbols, they'll 1184 * fail the whitelist tests and cause lots of false alarms ... fixable 1185 * only by merging __exit and __init sections into __text, bloating 1186 * the kernel (which is especially evil on embedded platforms). 1187 */ 1188static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym) 1189{ 1190 const char *name = elf->strtab + sym->st_name; 1191 1192 if (!name || !strlen(name)) 1193 return 0; 1194 return !is_arm_mapping_symbol(name); 1195} 1196 1197/* 1198 * Find symbols before or equal addr and after addr - in the section sec. 1199 * If we find two symbols with equal offset prefer one with a valid name. 1200 * The ELF format may have a better way to detect what type of symbol 1201 * it is, but this works for now. 1202 **/ 1203static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr, 1204 const char *sec) 1205{ 1206 Elf_Sym *sym; 1207 Elf_Sym *near = NULL; 1208 Elf_Addr distance = ~0; 1209 1210 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { 1211 const char *symsec; 1212 1213 if (is_shndx_special(sym->st_shndx)) 1214 continue; 1215 symsec = sec_name(elf, get_secindex(elf, sym)); 1216 if (strcmp(symsec, sec) != 0) 1217 continue; 1218 if (!is_valid_name(elf, sym)) 1219 continue; 1220 if (sym->st_value <= addr) { 1221 if ((addr - sym->st_value) < distance) { 1222 distance = addr - sym->st_value; 1223 near = sym; 1224 } else if ((addr - sym->st_value) == distance) { 1225 near = sym; 1226 } 1227 } 1228 } 1229 return near; 1230} 1231 1232/* 1233 * Convert a section name to the function/data attribute 1234 * .init.text => __init 1235 * .cpuinit.data => __cpudata 1236 * .memexitconst => __memconst 1237 * etc. 1238 * 1239 * The memory of returned value has been allocated on a heap. The user of this 1240 * method should free it after usage. 1241*/ 1242static char *sec2annotation(const char *s) 1243{ 1244 if (match(s, init_exit_sections)) { 1245 char *p = malloc(20); 1246 char *r = p; 1247 1248 *p++ = '_'; 1249 *p++ = '_'; 1250 if (*s == '.') 1251 s++; 1252 while (*s && *s != '.') 1253 *p++ = *s++; 1254 *p = '\0'; 1255 if (*s == '.') 1256 s++; 1257 if (strstr(s, "rodata") != NULL) 1258 strcat(p, "const "); 1259 else if (strstr(s, "data") != NULL) 1260 strcat(p, "data "); 1261 else 1262 strcat(p, " "); 1263 return r; 1264 } else { 1265 return strdup(""); 1266 } 1267} 1268 1269static int is_function(Elf_Sym *sym) 1270{ 1271 if (sym) 1272 return ELF_ST_TYPE(sym->st_info) == STT_FUNC; 1273 else 1274 return -1; 1275} 1276 1277static void print_section_list(const char * const list[20]) 1278{ 1279 const char *const *s = list; 1280 1281 while (*s) { 1282 fprintf(stderr, "%s", *s); 1283 s++; 1284 if (*s) 1285 fprintf(stderr, ", "); 1286 } 1287 fprintf(stderr, "\n"); 1288} 1289 1290/* 1291 * Print a warning about a section mismatch. 1292 * Try to find symbols near it so user can find it. 1293 * Check whitelist before warning - it may be a false positive. 1294 */ 1295static void report_sec_mismatch(const char *modname, 1296 const struct sectioncheck *mismatch, 1297 const char *fromsec, 1298 unsigned long long fromaddr, 1299 const char *fromsym, 1300 int from_is_func, 1301 const char *tosec, const char *tosym, 1302 int to_is_func) 1303{ 1304 const char *from, *from_p; 1305 const char *to, *to_p; 1306 char *prl_from; 1307 char *prl_to; 1308 1309 switch (from_is_func) { 1310 case 0: from = "variable"; from_p = ""; break; 1311 case 1: from = "function"; from_p = "()"; break; 1312 default: from = "(unknown reference)"; from_p = ""; break; 1313 } 1314 switch (to_is_func) { 1315 case 0: to = "variable"; to_p = ""; break; 1316 case 1: to = "function"; to_p = "()"; break; 1317 default: to = "(unknown reference)"; to_p = ""; break; 1318 } 1319 1320 sec_mismatch_count++; 1321 if (!sec_mismatch_verbose) 1322 return; 1323 1324 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s " 1325 "to the %s %s:%s%s\n", 1326 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec, 1327 tosym, to_p); 1328 1329 switch (mismatch->mismatch) { 1330 case TEXT_TO_ANY_INIT: 1331 prl_from = sec2annotation(fromsec); 1332 prl_to = sec2annotation(tosec); 1333 fprintf(stderr, 1334 "The function %s%s() references\n" 1335 "the %s %s%s%s.\n" 1336 "This is often because %s lacks a %s\n" 1337 "annotation or the annotation of %s is wrong.\n", 1338 prl_from, fromsym, 1339 to, prl_to, tosym, to_p, 1340 fromsym, prl_to, tosym); 1341 free(prl_from); 1342 free(prl_to); 1343 break; 1344 case DATA_TO_ANY_INIT: { 1345 prl_to = sec2annotation(tosec); 1346 fprintf(stderr, 1347 "The variable %s references\n" 1348 "the %s %s%s%s\n" 1349 "If the reference is valid then annotate the\n" 1350 "variable with __init* or __refdata (see linux/init.h) " 1351 "or name the variable:\n", 1352 fromsym, to, prl_to, tosym, to_p); 1353 print_section_list(mismatch->symbol_white_list); 1354 free(prl_to); 1355 break; 1356 } 1357 case TEXT_TO_ANY_EXIT: 1358 prl_to = sec2annotation(tosec); 1359 fprintf(stderr, 1360 "The function %s() references a %s in an exit section.\n" 1361 "Often the %s %s%s has valid usage outside the exit section\n" 1362 "and the fix is to remove the %sannotation of %s.\n", 1363 fromsym, to, to, tosym, to_p, prl_to, tosym); 1364 free(prl_to); 1365 break; 1366 case DATA_TO_ANY_EXIT: { 1367 prl_to = sec2annotation(tosec); 1368 fprintf(stderr, 1369 "The variable %s references\n" 1370 "the %s %s%s%s\n" 1371 "If the reference is valid then annotate the\n" 1372 "variable with __exit* (see linux/init.h) or " 1373 "name the variable:\n", 1374 fromsym, to, prl_to, tosym, to_p); 1375 print_section_list(mismatch->symbol_white_list); 1376 free(prl_to); 1377 break; 1378 } 1379 case XXXINIT_TO_SOME_INIT: 1380 case XXXEXIT_TO_SOME_EXIT: 1381 prl_from = sec2annotation(fromsec); 1382 prl_to = sec2annotation(tosec); 1383 fprintf(stderr, 1384 "The %s %s%s%s references\n" 1385 "a %s %s%s%s.\n" 1386 "If %s is only used by %s then\n" 1387 "annotate %s with a matching annotation.\n", 1388 from, prl_from, fromsym, from_p, 1389 to, prl_to, tosym, to_p, 1390 tosym, fromsym, tosym); 1391 free(prl_from); 1392 free(prl_to); 1393 break; 1394 case ANY_INIT_TO_ANY_EXIT: 1395 prl_from = sec2annotation(fromsec); 1396 prl_to = sec2annotation(tosec); 1397 fprintf(stderr, 1398 "The %s %s%s%s references\n" 1399 "a %s %s%s%s.\n" 1400 "This is often seen when error handling " 1401 "in the init function\n" 1402 "uses functionality in the exit path.\n" 1403 "The fix is often to remove the %sannotation of\n" 1404 "%s%s so it may be used outside an exit section.\n", 1405 from, prl_from, fromsym, from_p, 1406 to, prl_to, tosym, to_p, 1407 prl_to, tosym, to_p); 1408 free(prl_from); 1409 free(prl_to); 1410 break; 1411 case ANY_EXIT_TO_ANY_INIT: 1412 prl_from = sec2annotation(fromsec); 1413 prl_to = sec2annotation(tosec); 1414 fprintf(stderr, 1415 "The %s %s%s%s references\n" 1416 "a %s %s%s%s.\n" 1417 "This is often seen when error handling " 1418 "in the exit function\n" 1419 "uses functionality in the init path.\n" 1420 "The fix is often to remove the %sannotation of\n" 1421 "%s%s so it may be used outside an init section.\n", 1422 from, prl_from, fromsym, from_p, 1423 to, prl_to, tosym, to_p, 1424 prl_to, tosym, to_p); 1425 free(prl_from); 1426 free(prl_to); 1427 break; 1428 case EXPORT_TO_INIT_EXIT: 1429 prl_to = sec2annotation(tosec); 1430 fprintf(stderr, 1431 "The symbol %s is exported and annotated %s\n" 1432 "Fix this by removing the %sannotation of %s " 1433 "or drop the export.\n", 1434 tosym, prl_to, prl_to, tosym); 1435 free(prl_to); 1436 break; 1437 } 1438 fprintf(stderr, "\n"); 1439} 1440 1441static void check_section_mismatch(const char *modname, struct elf_info *elf, 1442 Elf_Rela *r, Elf_Sym *sym, const char *fromsec) 1443{ 1444 const char *tosec; 1445 const struct sectioncheck *mismatch; 1446 1447 tosec = sec_name(elf, get_secindex(elf, sym)); 1448 mismatch = section_mismatch(fromsec, tosec); 1449 if (mismatch) { 1450 Elf_Sym *to; 1451 Elf_Sym *from; 1452 const char *tosym; 1453 const char *fromsym; 1454 1455 from = find_elf_symbol2(elf, r->r_offset, fromsec); 1456 fromsym = sym_name(elf, from); 1457 to = find_elf_symbol(elf, r->r_addend, sym); 1458 tosym = sym_name(elf, to); 1459 1460 /* check whitelist - we may ignore it */ 1461 if (secref_whitelist(mismatch, 1462 fromsec, fromsym, tosec, tosym)) { 1463 report_sec_mismatch(modname, mismatch, 1464 fromsec, r->r_offset, fromsym, 1465 is_function(from), tosec, tosym, 1466 is_function(to)); 1467 } 1468 } 1469} 1470 1471static unsigned int *reloc_location(struct elf_info *elf, 1472 Elf_Shdr *sechdr, Elf_Rela *r) 1473{ 1474 Elf_Shdr *sechdrs = elf->sechdrs; 1475 int section = sechdr->sh_info; 1476 1477 return (void *)elf->hdr + sechdrs[section].sh_offset + 1478 r->r_offset; 1479} 1480 1481static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1482{ 1483 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1484 unsigned int *location = reloc_location(elf, sechdr, r); 1485 1486 switch (r_typ) { 1487 case R_386_32: 1488 r->r_addend = TO_NATIVE(*location); 1489 break; 1490 case R_386_PC32: 1491 r->r_addend = TO_NATIVE(*location) + 4; 1492 /* For CONFIG_RELOCATABLE=y */ 1493 if (elf->hdr->e_type == ET_EXEC) 1494 r->r_addend += r->r_offset; 1495 break; 1496 } 1497 return 0; 1498} 1499 1500static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1501{ 1502 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1503 1504 switch (r_typ) { 1505 case R_ARM_ABS32: 1506 /* From ARM ABI: (S + A) | T */ 1507 r->r_addend = (int)(long) 1508 (elf->symtab_start + ELF_R_SYM(r->r_info)); 1509 break; 1510 case R_ARM_PC24: 1511 /* From ARM ABI: ((S + A) | T) - P */ 1512 r->r_addend = (int)(long)(elf->hdr + 1513 sechdr->sh_offset + 1514 (r->r_offset - sechdr->sh_addr)); 1515 break; 1516 default: 1517 return 1; 1518 } 1519 return 0; 1520} 1521 1522static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1523{ 1524 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1525 unsigned int *location = reloc_location(elf, sechdr, r); 1526 unsigned int inst; 1527 1528 if (r_typ == R_MIPS_HI16) 1529 return 1; /* skip this */ 1530 inst = TO_NATIVE(*location); 1531 switch (r_typ) { 1532 case R_MIPS_LO16: 1533 r->r_addend = inst & 0xffff; 1534 break; 1535 case R_MIPS_26: 1536 r->r_addend = (inst & 0x03ffffff) << 2; 1537 break; 1538 case R_MIPS_32: 1539 r->r_addend = inst; 1540 break; 1541 } 1542 return 0; 1543} 1544 1545static void section_rela(const char *modname, struct elf_info *elf, 1546 Elf_Shdr *sechdr) 1547{ 1548 Elf_Sym *sym; 1549 Elf_Rela *rela; 1550 Elf_Rela r; 1551 unsigned int r_sym; 1552 const char *fromsec; 1553 1554 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset; 1555 Elf_Rela *stop = (void *)start + sechdr->sh_size; 1556 1557 fromsec = sech_name(elf, sechdr); 1558 fromsec += strlen(".rela"); 1559 /* if from section (name) is know good then skip it */ 1560 if (match(fromsec, section_white_list)) 1561 return; 1562 1563 for (rela = start; rela < stop; rela++) { 1564 r.r_offset = TO_NATIVE(rela->r_offset); 1565#if KERNEL_ELFCLASS == ELFCLASS64 1566 if (elf->hdr->e_machine == EM_MIPS) { 1567 unsigned int r_typ; 1568 r_sym = ELF64_MIPS_R_SYM(rela->r_info); 1569 r_sym = TO_NATIVE(r_sym); 1570 r_typ = ELF64_MIPS_R_TYPE(rela->r_info); 1571 r.r_info = ELF64_R_INFO(r_sym, r_typ); 1572 } else { 1573 r.r_info = TO_NATIVE(rela->r_info); 1574 r_sym = ELF_R_SYM(r.r_info); 1575 } 1576#else 1577 r.r_info = TO_NATIVE(rela->r_info); 1578 r_sym = ELF_R_SYM(r.r_info); 1579#endif 1580 r.r_addend = TO_NATIVE(rela->r_addend); 1581 sym = elf->symtab_start + r_sym; 1582 /* Skip special sections */ 1583 if (is_shndx_special(sym->st_shndx)) 1584 continue; 1585 check_section_mismatch(modname, elf, &r, sym, fromsec); 1586 } 1587} 1588 1589static void section_rel(const char *modname, struct elf_info *elf, 1590 Elf_Shdr *sechdr) 1591{ 1592 Elf_Sym *sym; 1593 Elf_Rel *rel; 1594 Elf_Rela r; 1595 unsigned int r_sym; 1596 const char *fromsec; 1597 1598 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset; 1599 Elf_Rel *stop = (void *)start + sechdr->sh_size; 1600 1601 fromsec = sech_name(elf, sechdr); 1602 fromsec += strlen(".rel"); 1603 /* if from section (name) is know good then skip it */ 1604 if (match(fromsec, section_white_list)) 1605 return; 1606 1607 for (rel = start; rel < stop; rel++) { 1608 r.r_offset = TO_NATIVE(rel->r_offset); 1609#if KERNEL_ELFCLASS == ELFCLASS64 1610 if (elf->hdr->e_machine == EM_MIPS) { 1611 unsigned int r_typ; 1612 r_sym = ELF64_MIPS_R_SYM(rel->r_info); 1613 r_sym = TO_NATIVE(r_sym); 1614 r_typ = ELF64_MIPS_R_TYPE(rel->r_info); 1615 r.r_info = ELF64_R_INFO(r_sym, r_typ); 1616 } else { 1617 r.r_info = TO_NATIVE(rel->r_info); 1618 r_sym = ELF_R_SYM(r.r_info); 1619 } 1620#else 1621 r.r_info = TO_NATIVE(rel->r_info); 1622 r_sym = ELF_R_SYM(r.r_info); 1623#endif 1624 r.r_addend = 0; 1625 switch (elf->hdr->e_machine) { 1626 case EM_386: 1627 if (addend_386_rel(elf, sechdr, &r)) 1628 continue; 1629 break; 1630 case EM_ARM: 1631 if (addend_arm_rel(elf, sechdr, &r)) 1632 continue; 1633 break; 1634 case EM_MIPS: 1635 if (addend_mips_rel(elf, sechdr, &r)) 1636 continue; 1637 break; 1638 } 1639 sym = elf->symtab_start + r_sym; 1640 /* Skip special sections */ 1641 if (is_shndx_special(sym->st_shndx)) 1642 continue; 1643 check_section_mismatch(modname, elf, &r, sym, fromsec); 1644 } 1645} 1646 1647/** 1648 * A module includes a number of sections that are discarded 1649 * either when loaded or when used as built-in. 1650 * For loaded modules all functions marked __init and all data 1651 * marked __initdata will be discarded when the module has been initialized. 1652 * Likewise for modules used built-in the sections marked __exit 1653 * are discarded because __exit marked function are supposed to be called 1654 * only when a module is unloaded which never happens for built-in modules. 1655 * The check_sec_ref() function traverses all relocation records 1656 * to find all references to a section that reference a section that will 1657 * be discarded and warns about it. 1658 **/ 1659static void check_sec_ref(struct module *mod, const char *modname, 1660 struct elf_info *elf) 1661{ 1662 int i; 1663 Elf_Shdr *sechdrs = elf->sechdrs; 1664 1665 /* Walk through all sections */ 1666 for (i = 0; i < elf->num_sections; i++) { 1667 check_section(modname, elf, &elf->sechdrs[i]); 1668 /* We want to process only relocation sections and not .init */ 1669 if (sechdrs[i].sh_type == SHT_RELA) 1670 section_rela(modname, elf, &elf->sechdrs[i]); 1671 else if (sechdrs[i].sh_type == SHT_REL) 1672 section_rel(modname, elf, &elf->sechdrs[i]); 1673 } 1674} 1675 1676static void read_symbols(char *modname) 1677{ 1678 const char *symname; 1679 char *version; 1680 char *license; 1681 struct module *mod; 1682 struct elf_info info = { }; 1683 Elf_Sym *sym; 1684 1685 if (!parse_elf(&info, modname)) 1686 return; 1687 1688 mod = new_module(modname); 1689 1690 /* When there's no vmlinux, don't print warnings about 1691 * unresolved symbols (since there'll be too many ;) */ 1692 if (is_vmlinux(modname)) { 1693 have_vmlinux = 1; 1694 mod->skip = 1; 1695 } 1696 1697 license = get_modinfo(info.modinfo, info.modinfo_len, "license"); 1698 if (info.modinfo && !license && !is_vmlinux(modname)) 1699 warn("modpost: missing MODULE_LICENSE() in %s\n" 1700 "see include/linux/module.h for " 1701 "more information\n", modname); 1702 while (license) { 1703 if (license_is_gpl_compatible(license)) 1704 mod->gpl_compatible = 1; 1705 else { 1706 mod->gpl_compatible = 0; 1707 break; 1708 } 1709 license = get_next_modinfo(info.modinfo, info.modinfo_len, 1710 "license", license); 1711 } 1712 1713 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { 1714 symname = info.strtab + sym->st_name; 1715 1716 handle_modversions(mod, &info, sym, symname); 1717 handle_moddevtable(mod, &info, sym, symname); 1718 } 1719 if (!is_vmlinux(modname) || 1720 (is_vmlinux(modname) && vmlinux_section_warnings)) 1721 check_sec_ref(mod, modname, &info); 1722 1723 version = get_modinfo(info.modinfo, info.modinfo_len, "version"); 1724 if (version) 1725 maybe_frob_rcs_version(modname, version, info.modinfo, 1726 version - (char *)info.hdr); 1727 if (version || (all_versions && !is_vmlinux(modname))) 1728 get_src_version(modname, mod->srcversion, 1729 sizeof(mod->srcversion)-1); 1730 1731 parse_elf_finish(&info); 1732 1733 /* Our trick to get versioning for module struct etc. - it's 1734 * never passed as an argument to an exported function, so 1735 * the automatic versioning doesn't pick it up, but it's really 1736 * important anyhow */ 1737 if (modversions) 1738 mod->unres = alloc_symbol("module_layout", 0, mod->unres); 1739} 1740 1741#define SZ 500 1742 1743/* We first write the generated file into memory using the 1744 * following helper, then compare to the file on disk and 1745 * only update the later if anything changed */ 1746 1747void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf, 1748 const char *fmt, ...) 1749{ 1750 char tmp[SZ]; 1751 int len; 1752 va_list ap; 1753 1754 va_start(ap, fmt); 1755 len = vsnprintf(tmp, SZ, fmt, ap); 1756 buf_write(buf, tmp, len); 1757 va_end(ap); 1758} 1759 1760void buf_write(struct buffer *buf, const char *s, int len) 1761{ 1762 if (buf->size - buf->pos < len) { 1763 buf->size += len + SZ; 1764 buf->p = realloc(buf->p, buf->size); 1765 } 1766 strncpy(buf->p + buf->pos, s, len); 1767 buf->pos += len; 1768} 1769 1770static void check_for_gpl_usage(enum export exp, const char *m, const char *s) 1771{ 1772 const char *e = is_vmlinux(m) ?"":".ko"; 1773 1774 switch (exp) { 1775 case export_gpl: 1776 fatal("modpost: GPL-incompatible module %s%s " 1777 "uses GPL-only symbol '%s'\n", m, e, s); 1778 break; 1779 case export_unused_gpl: 1780 fatal("modpost: GPL-incompatible module %s%s " 1781 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s); 1782 break; 1783 case export_gpl_future: 1784 warn("modpost: GPL-incompatible module %s%s " 1785 "uses future GPL-only symbol '%s'\n", m, e, s); 1786 break; 1787 case export_plain: 1788 case export_unused: 1789 case export_unknown: 1790 /* ignore */ 1791 break; 1792 } 1793} 1794 1795static void check_for_unused(enum export exp, const char *m, const char *s) 1796{ 1797 const char *e = is_vmlinux(m) ?"":".ko"; 1798 1799 switch (exp) { 1800 case export_unused: 1801 case export_unused_gpl: 1802 warn("modpost: module %s%s " 1803 "uses symbol '%s' marked UNUSED\n", m, e, s); 1804 break; 1805 default: 1806 /* ignore */ 1807 break; 1808 } 1809} 1810 1811static void check_exports(struct module *mod) 1812{ 1813 struct symbol *s, *exp; 1814 1815 for (s = mod->unres; s; s = s->next) { 1816 const char *basename; 1817 exp = find_symbol(s->name); 1818 if (!exp || exp->module == mod) 1819 continue; 1820 basename = strrchr(mod->name, '/'); 1821 if (basename) 1822 basename++; 1823 else 1824 basename = mod->name; 1825 if (!mod->gpl_compatible) 1826 check_for_gpl_usage(exp->export, basename, exp->name); 1827 check_for_unused(exp->export, basename, exp->name); 1828 } 1829} 1830 1831/** 1832 * Header for the generated file 1833 **/ 1834static void add_header(struct buffer *b, struct module *mod) 1835{ 1836 buf_printf(b, "#include <linux/module.h>\n"); 1837 buf_printf(b, "#include <linux/vermagic.h>\n"); 1838 buf_printf(b, "#include <linux/compiler.h>\n"); 1839 buf_printf(b, "\n"); 1840 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n"); 1841 buf_printf(b, "\n"); 1842 buf_printf(b, "struct module __this_module\n"); 1843 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n"); 1844 buf_printf(b, " .name = KBUILD_MODNAME,\n"); 1845 if (mod->has_init) 1846 buf_printf(b, " .init = init_module,\n"); 1847 if (mod->has_cleanup) 1848 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n" 1849 " .exit = cleanup_module,\n" 1850 "#endif\n"); 1851 buf_printf(b, " .arch = MODULE_ARCH_INIT,\n"); 1852 buf_printf(b, "};\n"); 1853} 1854 1855static void add_staging_flag(struct buffer *b, const char *name) 1856{ 1857 static const char *staging_dir = "drivers/staging"; 1858 1859 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0) 1860 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); 1861} 1862 1863/** 1864 * Record CRCs for unresolved symbols 1865 **/ 1866static int add_versions(struct buffer *b, struct module *mod) 1867{ 1868 struct symbol *s, *exp; 1869 int err = 0; 1870 1871 for (s = mod->unres; s; s = s->next) { 1872 exp = find_symbol(s->name); 1873 if (!exp || exp->module == mod) { 1874 if (have_vmlinux && !s->weak) { 1875 if (warn_unresolved) { 1876 warn("\"%s\" [%s.ko] undefined!\n", 1877 s->name, mod->name); 1878 } else { 1879 merror("\"%s\" [%s.ko] undefined!\n", 1880 s->name, mod->name); 1881 err = 1; 1882 } 1883 } 1884 continue; 1885 } 1886 s->module = exp->module; 1887 s->crc_valid = exp->crc_valid; 1888 s->crc = exp->crc; 1889 } 1890 1891 if (!modversions) 1892 return err; 1893 1894 buf_printf(b, "\n"); 1895 buf_printf(b, "static const struct modversion_info ____versions[]\n"); 1896 buf_printf(b, "__used\n"); 1897 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n"); 1898 1899 for (s = mod->unres; s; s = s->next) { 1900 if (!s->module) 1901 continue; 1902 if (!s->crc_valid) { 1903 warn("\"%s\" [%s.ko] has no CRC!\n", 1904 s->name, mod->name); 1905 continue; 1906 } 1907 buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name); 1908 } 1909 1910 buf_printf(b, "};\n"); 1911 1912 return err; 1913} 1914 1915static void add_depends(struct buffer *b, struct module *mod, 1916 struct module *modules) 1917{ 1918 struct symbol *s; 1919 struct module *m; 1920 int first = 1; 1921 1922 for (m = modules; m; m = m->next) 1923 m->seen = is_vmlinux(m->name); 1924 1925 buf_printf(b, "\n"); 1926 buf_printf(b, "static const char __module_depends[]\n"); 1927 buf_printf(b, "__used\n"); 1928 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n"); 1929 buf_printf(b, "\"depends="); 1930 for (s = mod->unres; s; s = s->next) { 1931 const char *p; 1932 if (!s->module) 1933 continue; 1934 1935 if (s->module->seen) 1936 continue; 1937 1938 s->module->seen = 1; 1939 p = strrchr(s->module->name, '/'); 1940 if (p) 1941 p++; 1942 else 1943 p = s->module->name; 1944 buf_printf(b, "%s%s", first ? "" : ",", p); 1945 first = 0; 1946 } 1947 buf_printf(b, "\";\n"); 1948} 1949 1950static void add_srcversion(struct buffer *b, struct module *mod) 1951{ 1952 if (mod->srcversion[0]) { 1953 buf_printf(b, "\n"); 1954 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n", 1955 mod->srcversion); 1956 } 1957} 1958 1959static void write_if_changed(struct buffer *b, const char *fname) 1960{ 1961 char *tmp; 1962 FILE *file; 1963 struct stat st; 1964 1965 file = fopen(fname, "r"); 1966 if (!file) 1967 goto write; 1968 1969 if (fstat(fileno(file), &st) < 0) 1970 goto close_write; 1971 1972 if (st.st_size != b->pos) 1973 goto close_write; 1974 1975 tmp = NOFAIL(malloc(b->pos)); 1976 if (fread(tmp, 1, b->pos, file) != b->pos) 1977 goto free_write; 1978 1979 if (memcmp(tmp, b->p, b->pos) != 0) 1980 goto free_write; 1981 1982 free(tmp); 1983 fclose(file); 1984 return; 1985 1986 free_write: 1987 free(tmp); 1988 close_write: 1989 fclose(file); 1990 write: 1991 file = fopen(fname, "w"); 1992 if (!file) { 1993 perror(fname); 1994 exit(1); 1995 } 1996 if (fwrite(b->p, 1, b->pos, file) != b->pos) { 1997 perror(fname); 1998 exit(1); 1999 } 2000 fclose(file); 2001} 2002 2003/* parse Module.symvers file. line format: 2004 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something] 2005 **/ 2006static void read_dump(const char *fname, unsigned int kernel) 2007{ 2008 unsigned long size, pos = 0; 2009 void *file = grab_file(fname, &size); 2010 char *line; 2011 2012 if (!file) 2013 /* No symbol versions, silently ignore */ 2014 return; 2015 2016 while ((line = get_next_line(&pos, file, size))) { 2017 char *symname, *modname, *d, *export, *end; 2018 unsigned int crc; 2019 struct module *mod; 2020 struct symbol *s; 2021 2022 if (!(symname = strchr(line, '\t'))) 2023 goto fail; 2024 *symname++ = '\0'; 2025 if (!(modname = strchr(symname, '\t'))) 2026 goto fail; 2027 *modname++ = '\0'; 2028 if ((export = strchr(modname, '\t')) != NULL) 2029 *export++ = '\0'; 2030 if (export && ((end = strchr(export, '\t')) != NULL)) 2031 *end = '\0'; 2032 crc = strtoul(line, &d, 16); 2033 if (*symname == '\0' || *modname == '\0' || *d != '\0') 2034 goto fail; 2035 mod = find_module(modname); 2036 if (!mod) { 2037 if (is_vmlinux(modname)) 2038 have_vmlinux = 1; 2039 mod = new_module(modname); 2040 mod->skip = 1; 2041 } 2042 s = sym_add_exported(symname, mod, export_no(export)); 2043 s->kernel = kernel; 2044 s->preloaded = 1; 2045 sym_update_crc(symname, mod, crc, export_no(export)); 2046 } 2047 return; 2048fail: 2049 fatal("parse error in symbol dump file\n"); 2050} 2051 2052/* For normal builds always dump all symbols. 2053 * For external modules only dump symbols 2054 * that are not read from kernel Module.symvers. 2055 **/ 2056static int dump_sym(struct symbol *sym) 2057{ 2058 if (!external_module) 2059 return 1; 2060 if (sym->vmlinux || sym->kernel) 2061 return 0; 2062 return 1; 2063} 2064 2065static void write_dump(const char *fname) 2066{ 2067 struct buffer buf = { }; 2068 struct symbol *symbol; 2069 int n; 2070 2071 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) { 2072 symbol = symbolhash[n]; 2073 while (symbol) { 2074 if (dump_sym(symbol)) 2075 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n", 2076 symbol->crc, symbol->name, 2077 symbol->module->name, 2078 export_str(symbol->export)); 2079 symbol = symbol->next; 2080 } 2081 } 2082 write_if_changed(&buf, fname); 2083} 2084 2085struct ext_sym_list { 2086 struct ext_sym_list *next; 2087 const char *file; 2088}; 2089 2090int main(int argc, char **argv) 2091{ 2092 struct module *mod; 2093 struct buffer buf = { }; 2094 char *kernel_read = NULL, *module_read = NULL; 2095 char *dump_write = NULL; 2096 int opt; 2097 int err; 2098 struct ext_sym_list *extsym_iter; 2099 struct ext_sym_list *extsym_start = NULL; 2100 2101 while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) { 2102 switch (opt) { 2103 case 'i': 2104 kernel_read = optarg; 2105 break; 2106 case 'I': 2107 module_read = optarg; 2108 external_module = 1; 2109 break; 2110 case 'c': 2111 cross_build = 1; 2112 break; 2113 case 'e': 2114 external_module = 1; 2115 extsym_iter = 2116 NOFAIL(malloc(sizeof(*extsym_iter))); 2117 extsym_iter->next = extsym_start; 2118 extsym_iter->file = optarg; 2119 extsym_start = extsym_iter; 2120 break; 2121 case 'm': 2122 modversions = 1; 2123 break; 2124 case 'o': 2125 dump_write = optarg; 2126 break; 2127 case 'a': 2128 all_versions = 1; 2129 break; 2130 case 's': 2131 vmlinux_section_warnings = 0; 2132 break; 2133 case 'S': 2134 sec_mismatch_verbose = 0; 2135 break; 2136 case 'w': 2137 warn_unresolved = 1; 2138 break; 2139 default: 2140 exit(1); 2141 } 2142 } 2143 2144 if (kernel_read) 2145 read_dump(kernel_read, 1); 2146 if (module_read) 2147 read_dump(module_read, 0); 2148 while (extsym_start) { 2149 read_dump(extsym_start->file, 0); 2150 extsym_iter = extsym_start->next; 2151 free(extsym_start); 2152 extsym_start = extsym_iter; 2153 } 2154 2155 while (optind < argc) 2156 read_symbols(argv[optind++]); 2157 2158 for (mod = modules; mod; mod = mod->next) { 2159 if (mod->skip) 2160 continue; 2161 check_exports(mod); 2162 } 2163 2164 err = 0; 2165 2166 for (mod = modules; mod; mod = mod->next) { 2167 char fname[strlen(mod->name) + 10]; 2168 2169 if (mod->skip) 2170 continue; 2171 2172 buf.pos = 0; 2173 2174 add_header(&buf, mod); 2175 add_staging_flag(&buf, mod->name); 2176 err |= add_versions(&buf, mod); 2177 add_depends(&buf, mod, modules); 2178 add_moddevtable(&buf, mod); 2179 add_srcversion(&buf, mod); 2180 2181 sprintf(fname, "%s.mod.c", mod->name); 2182 write_if_changed(&buf, fname); 2183 } 2184 2185 if (dump_write) 2186 write_dump(dump_write); 2187 if (sec_mismatch_count && !sec_mismatch_verbose) 2188 warn("modpost: Found %d section mismatch(es).\n" 2189 "To see full details build your kernel with:\n" 2190 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n", 2191 sec_mismatch_count); 2192 2193 return err; 2194} 2195