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