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 <limits.h> 19 #include <stdbool.h> 20 #include "modpost.h" 21 #include "../../include/generated/autoconf.h" 22 #include "../../include/linux/license.h" 23 #include "../../include/linux/export.h" 24 25 /* Are we using CONFIG_MODVERSIONS? */ 26 int modversions = 0; 27 /* Warn about undefined symbols? (do so if we have vmlinux) */ 28 int have_vmlinux = 0; 29 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ 30 static int all_versions = 0; 31 /* If we are modposting external module set to 1 */ 32 static int external_module = 0; 33 /* Warn about section mismatch in vmlinux if set to 1 */ 34 static int vmlinux_section_warnings = 1; 35 /* Only warn about unresolved symbols */ 36 static int warn_unresolved = 0; 37 /* How a symbol is exported */ 38 static int sec_mismatch_count = 0; 39 static int sec_mismatch_verbose = 1; 40 41 enum export { 42 export_plain, export_unused, export_gpl, 43 export_unused_gpl, export_gpl_future, export_unknown 44 }; 45 46 #define PRINTF __attribute__ ((format (printf, 1, 2))) 47 48 PRINTF void fatal(const char *fmt, ...) 49 { 50 va_list arglist; 51 52 fprintf(stderr, "FATAL: "); 53 54 va_start(arglist, fmt); 55 vfprintf(stderr, fmt, arglist); 56 va_end(arglist); 57 58 exit(1); 59 } 60 61 PRINTF void warn(const char *fmt, ...) 62 { 63 va_list arglist; 64 65 fprintf(stderr, "WARNING: "); 66 67 va_start(arglist, fmt); 68 vfprintf(stderr, fmt, arglist); 69 va_end(arglist); 70 } 71 72 PRINTF void merror(const char *fmt, ...) 73 { 74 va_list arglist; 75 76 fprintf(stderr, "ERROR: "); 77 78 va_start(arglist, fmt); 79 vfprintf(stderr, fmt, arglist); 80 va_end(arglist); 81 } 82 83 static inline bool strends(const char *str, const char *postfix) 84 { 85 if (strlen(str) < strlen(postfix)) 86 return false; 87 88 return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0; 89 } 90 91 static int is_vmlinux(const char *modname) 92 { 93 const char *myname; 94 95 myname = strrchr(modname, '/'); 96 if (myname) 97 myname++; 98 else 99 myname = modname; 100 101 return (strcmp(myname, "vmlinux") == 0) || 102 (strcmp(myname, "vmlinux.o") == 0); 103 } 104 105 void *do_nofail(void *ptr, const char *expr) 106 { 107 if (!ptr) 108 fatal("modpost: Memory allocation failure: %s.\n", expr); 109 110 return ptr; 111 } 112 113 /* A list of all modules we processed */ 114 static struct module *modules; 115 116 static struct module *find_module(char *modname) 117 { 118 struct module *mod; 119 120 for (mod = modules; mod; mod = mod->next) 121 if (strcmp(mod->name, modname) == 0) 122 break; 123 return mod; 124 } 125 126 static struct module *new_module(const char *modname) 127 { 128 struct module *mod; 129 char *p; 130 131 mod = NOFAIL(malloc(sizeof(*mod))); 132 memset(mod, 0, sizeof(*mod)); 133 p = NOFAIL(strdup(modname)); 134 135 /* strip trailing .o */ 136 if (strends(p, ".o")) { 137 p[strlen(p) - 2] = '\0'; 138 mod->is_dot_o = 1; 139 } 140 141 /* add to list */ 142 mod->name = p; 143 mod->gpl_compatible = -1; 144 mod->next = modules; 145 modules = mod; 146 147 return mod; 148 } 149 150 /* A hash of all exported symbols, 151 * struct symbol is also used for lists of unresolved symbols */ 152 153 #define SYMBOL_HASH_SIZE 1024 154 155 struct symbol { 156 struct symbol *next; 157 struct module *module; 158 unsigned int crc; 159 int crc_valid; 160 unsigned int weak:1; 161 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */ 162 unsigned int kernel:1; /* 1 if symbol is from kernel 163 * (only for external modules) **/ 164 unsigned int preloaded:1; /* 1 if symbol from Module.symvers */ 165 enum export export; /* Type of export */ 166 char name[0]; 167 }; 168 169 static struct symbol *symbolhash[SYMBOL_HASH_SIZE]; 170 171 /* This is based on the hash agorithm from gdbm, via tdb */ 172 static inline unsigned int tdb_hash(const char *name) 173 { 174 unsigned value; /* Used to compute the hash value. */ 175 unsigned i; /* Used to cycle through random values. */ 176 177 /* Set the initial value from the key size. */ 178 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++) 179 value = (value + (((unsigned char *)name)[i] << (i*5 % 24))); 180 181 return (1103515243 * value + 12345); 182 } 183 184 /** 185 * Allocate a new symbols for use in the hash of exported symbols or 186 * the list of unresolved symbols per module 187 **/ 188 static struct symbol *alloc_symbol(const char *name, unsigned int weak, 189 struct symbol *next) 190 { 191 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1)); 192 193 memset(s, 0, sizeof(*s)); 194 strcpy(s->name, name); 195 s->weak = weak; 196 s->next = next; 197 return s; 198 } 199 200 /* For the hash of exported symbols */ 201 static struct symbol *new_symbol(const char *name, struct module *module, 202 enum export export) 203 { 204 unsigned int hash; 205 struct symbol *new; 206 207 hash = tdb_hash(name) % SYMBOL_HASH_SIZE; 208 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]); 209 new->module = module; 210 new->export = export; 211 return new; 212 } 213 214 static struct symbol *find_symbol(const char *name) 215 { 216 struct symbol *s; 217 218 /* For our purposes, .foo matches foo. PPC64 needs this. */ 219 if (name[0] == '.') 220 name++; 221 222 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) { 223 if (strcmp(s->name, name) == 0) 224 return s; 225 } 226 return NULL; 227 } 228 229 static struct { 230 const char *str; 231 enum export export; 232 } export_list[] = { 233 { .str = "EXPORT_SYMBOL", .export = export_plain }, 234 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused }, 235 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl }, 236 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl }, 237 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future }, 238 { .str = "(unknown)", .export = export_unknown }, 239 }; 240 241 242 static const char *export_str(enum export ex) 243 { 244 return export_list[ex].str; 245 } 246 247 static enum export export_no(const char *s) 248 { 249 int i; 250 251 if (!s) 252 return export_unknown; 253 for (i = 0; export_list[i].export != export_unknown; i++) { 254 if (strcmp(export_list[i].str, s) == 0) 255 return export_list[i].export; 256 } 257 return export_unknown; 258 } 259 260 static const char *sec_name(struct elf_info *elf, int secindex); 261 262 #define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0) 263 264 static enum export export_from_secname(struct elf_info *elf, unsigned int sec) 265 { 266 const char *secname = sec_name(elf, sec); 267 268 if (strstarts(secname, "___ksymtab+")) 269 return export_plain; 270 else if (strstarts(secname, "___ksymtab_unused+")) 271 return export_unused; 272 else if (strstarts(secname, "___ksymtab_gpl+")) 273 return export_gpl; 274 else if (strstarts(secname, "___ksymtab_unused_gpl+")) 275 return export_unused_gpl; 276 else if (strstarts(secname, "___ksymtab_gpl_future+")) 277 return export_gpl_future; 278 else 279 return export_unknown; 280 } 281 282 static enum export export_from_sec(struct elf_info *elf, unsigned int sec) 283 { 284 if (sec == elf->export_sec) 285 return export_plain; 286 else if (sec == elf->export_unused_sec) 287 return export_unused; 288 else if (sec == elf->export_gpl_sec) 289 return export_gpl; 290 else if (sec == elf->export_unused_gpl_sec) 291 return export_unused_gpl; 292 else if (sec == elf->export_gpl_future_sec) 293 return export_gpl_future; 294 else 295 return export_unknown; 296 } 297 298 /** 299 * Add an exported symbol - it may have already been added without a 300 * CRC, in this case just update the CRC 301 **/ 302 static struct symbol *sym_add_exported(const char *name, struct module *mod, 303 enum export export) 304 { 305 struct symbol *s = find_symbol(name); 306 307 if (!s) { 308 s = new_symbol(name, mod, export); 309 } else { 310 if (!s->preloaded) { 311 warn("%s: '%s' exported twice. Previous export " 312 "was in %s%s\n", mod->name, name, 313 s->module->name, 314 is_vmlinux(s->module->name) ?"":".ko"); 315 } else { 316 /* In case Modules.symvers was out of date */ 317 s->module = mod; 318 } 319 } 320 s->preloaded = 0; 321 s->vmlinux = is_vmlinux(mod->name); 322 s->kernel = 0; 323 s->export = export; 324 return s; 325 } 326 327 static void sym_update_crc(const char *name, struct module *mod, 328 unsigned int crc, enum export export) 329 { 330 struct symbol *s = find_symbol(name); 331 332 if (!s) 333 s = new_symbol(name, mod, export); 334 s->crc = crc; 335 s->crc_valid = 1; 336 } 337 338 void *grab_file(const char *filename, unsigned long *size) 339 { 340 struct stat st; 341 void *map = MAP_FAILED; 342 int fd; 343 344 fd = open(filename, O_RDONLY); 345 if (fd < 0) 346 return NULL; 347 if (fstat(fd, &st)) 348 goto failed; 349 350 *size = st.st_size; 351 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); 352 353 failed: 354 close(fd); 355 if (map == MAP_FAILED) 356 return NULL; 357 return map; 358 } 359 360 /** 361 * Return a copy of the next line in a mmap'ed file. 362 * spaces in the beginning of the line is trimmed away. 363 * Return a pointer to a static buffer. 364 **/ 365 char *get_next_line(unsigned long *pos, void *file, unsigned long size) 366 { 367 static char line[4096]; 368 int skip = 1; 369 size_t len = 0; 370 signed char *p = (signed char *)file + *pos; 371 char *s = line; 372 373 for (; *pos < size ; (*pos)++) { 374 if (skip && isspace(*p)) { 375 p++; 376 continue; 377 } 378 skip = 0; 379 if (*p != '\n' && (*pos < size)) { 380 len++; 381 *s++ = *p++; 382 if (len > 4095) 383 break; /* Too long, stop */ 384 } else { 385 /* End of string */ 386 *s = '\0'; 387 return line; 388 } 389 } 390 /* End of buffer */ 391 return NULL; 392 } 393 394 void release_file(void *file, unsigned long size) 395 { 396 munmap(file, size); 397 } 398 399 static int parse_elf(struct elf_info *info, const char *filename) 400 { 401 unsigned int i; 402 Elf_Ehdr *hdr; 403 Elf_Shdr *sechdrs; 404 Elf_Sym *sym; 405 const char *secstrings; 406 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U; 407 408 hdr = grab_file(filename, &info->size); 409 if (!hdr) { 410 perror(filename); 411 exit(1); 412 } 413 info->hdr = hdr; 414 if (info->size < sizeof(*hdr)) { 415 /* file too small, assume this is an empty .o file */ 416 return 0; 417 } 418 /* Is this a valid ELF file? */ 419 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) || 420 (hdr->e_ident[EI_MAG1] != ELFMAG1) || 421 (hdr->e_ident[EI_MAG2] != ELFMAG2) || 422 (hdr->e_ident[EI_MAG3] != ELFMAG3)) { 423 /* Not an ELF file - silently ignore it */ 424 return 0; 425 } 426 /* Fix endianness in ELF header */ 427 hdr->e_type = TO_NATIVE(hdr->e_type); 428 hdr->e_machine = TO_NATIVE(hdr->e_machine); 429 hdr->e_version = TO_NATIVE(hdr->e_version); 430 hdr->e_entry = TO_NATIVE(hdr->e_entry); 431 hdr->e_phoff = TO_NATIVE(hdr->e_phoff); 432 hdr->e_shoff = TO_NATIVE(hdr->e_shoff); 433 hdr->e_flags = TO_NATIVE(hdr->e_flags); 434 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize); 435 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize); 436 hdr->e_phnum = TO_NATIVE(hdr->e_phnum); 437 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize); 438 hdr->e_shnum = TO_NATIVE(hdr->e_shnum); 439 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx); 440 sechdrs = (void *)hdr + hdr->e_shoff; 441 info->sechdrs = sechdrs; 442 443 /* Check if file offset is correct */ 444 if (hdr->e_shoff > info->size) { 445 fatal("section header offset=%lu in file '%s' is bigger than " 446 "filesize=%lu\n", (unsigned long)hdr->e_shoff, 447 filename, info->size); 448 return 0; 449 } 450 451 if (hdr->e_shnum == SHN_UNDEF) { 452 /* 453 * There are more than 64k sections, 454 * read count from .sh_size. 455 */ 456 info->num_sections = TO_NATIVE(sechdrs[0].sh_size); 457 } 458 else { 459 info->num_sections = hdr->e_shnum; 460 } 461 if (hdr->e_shstrndx == SHN_XINDEX) { 462 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link); 463 } 464 else { 465 info->secindex_strings = hdr->e_shstrndx; 466 } 467 468 /* Fix endianness in section headers */ 469 for (i = 0; i < info->num_sections; i++) { 470 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name); 471 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); 472 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags); 473 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr); 474 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset); 475 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size); 476 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link); 477 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info); 478 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign); 479 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize); 480 } 481 /* Find symbol table. */ 482 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset; 483 for (i = 1; i < info->num_sections; i++) { 484 const char *secname; 485 int nobits = sechdrs[i].sh_type == SHT_NOBITS; 486 487 if (!nobits && sechdrs[i].sh_offset > info->size) { 488 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > " 489 "sizeof(*hrd)=%zu\n", filename, 490 (unsigned long)sechdrs[i].sh_offset, 491 sizeof(*hdr)); 492 return 0; 493 } 494 secname = secstrings + sechdrs[i].sh_name; 495 if (strcmp(secname, ".modinfo") == 0) { 496 if (nobits) 497 fatal("%s has NOBITS .modinfo\n", filename); 498 info->modinfo = (void *)hdr + sechdrs[i].sh_offset; 499 info->modinfo_len = sechdrs[i].sh_size; 500 } else if (strcmp(secname, "__ksymtab") == 0) 501 info->export_sec = i; 502 else if (strcmp(secname, "__ksymtab_unused") == 0) 503 info->export_unused_sec = i; 504 else if (strcmp(secname, "__ksymtab_gpl") == 0) 505 info->export_gpl_sec = i; 506 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0) 507 info->export_unused_gpl_sec = i; 508 else if (strcmp(secname, "__ksymtab_gpl_future") == 0) 509 info->export_gpl_future_sec = i; 510 511 if (sechdrs[i].sh_type == SHT_SYMTAB) { 512 unsigned int sh_link_idx; 513 symtab_idx = i; 514 info->symtab_start = (void *)hdr + 515 sechdrs[i].sh_offset; 516 info->symtab_stop = (void *)hdr + 517 sechdrs[i].sh_offset + sechdrs[i].sh_size; 518 sh_link_idx = sechdrs[i].sh_link; 519 info->strtab = (void *)hdr + 520 sechdrs[sh_link_idx].sh_offset; 521 } 522 523 /* 32bit section no. table? ("more than 64k sections") */ 524 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) { 525 symtab_shndx_idx = i; 526 info->symtab_shndx_start = (void *)hdr + 527 sechdrs[i].sh_offset; 528 info->symtab_shndx_stop = (void *)hdr + 529 sechdrs[i].sh_offset + sechdrs[i].sh_size; 530 } 531 } 532 if (!info->symtab_start) 533 fatal("%s has no symtab?\n", filename); 534 535 /* Fix endianness in symbols */ 536 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) { 537 sym->st_shndx = TO_NATIVE(sym->st_shndx); 538 sym->st_name = TO_NATIVE(sym->st_name); 539 sym->st_value = TO_NATIVE(sym->st_value); 540 sym->st_size = TO_NATIVE(sym->st_size); 541 } 542 543 if (symtab_shndx_idx != ~0U) { 544 Elf32_Word *p; 545 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link) 546 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n", 547 filename, sechdrs[symtab_shndx_idx].sh_link, 548 symtab_idx); 549 /* Fix endianness */ 550 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop; 551 p++) 552 *p = TO_NATIVE(*p); 553 } 554 555 return 1; 556 } 557 558 static void parse_elf_finish(struct elf_info *info) 559 { 560 release_file(info->hdr, info->size); 561 } 562 563 static int ignore_undef_symbol(struct elf_info *info, const char *symname) 564 { 565 /* ignore __this_module, it will be resolved shortly */ 566 if (strcmp(symname, VMLINUX_SYMBOL_STR(__this_module)) == 0) 567 return 1; 568 /* ignore global offset table */ 569 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0) 570 return 1; 571 if (info->hdr->e_machine == EM_PPC) 572 /* Special register function linked on all modules during final link of .ko */ 573 if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 || 574 strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 || 575 strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 || 576 strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0) 577 return 1; 578 if (info->hdr->e_machine == EM_PPC64) 579 /* Special register function linked on all modules during final link of .ko */ 580 if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 || 581 strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0) 582 return 1; 583 /* Do not ignore this symbol */ 584 return 0; 585 } 586 587 #define CRC_PFX VMLINUX_SYMBOL_STR(__crc_) 588 #define KSYMTAB_PFX VMLINUX_SYMBOL_STR(__ksymtab_) 589 590 static void handle_modversions(struct module *mod, struct elf_info *info, 591 Elf_Sym *sym, const char *symname) 592 { 593 unsigned int crc; 594 enum export export; 595 596 if ((!is_vmlinux(mod->name) || mod->is_dot_o) && 597 strncmp(symname, "__ksymtab", 9) == 0) 598 export = export_from_secname(info, get_secindex(info, sym)); 599 else 600 export = export_from_sec(info, get_secindex(info, sym)); 601 602 switch (sym->st_shndx) { 603 case SHN_COMMON: 604 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name); 605 break; 606 case SHN_ABS: 607 /* CRC'd symbol */ 608 if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) { 609 crc = (unsigned int) sym->st_value; 610 sym_update_crc(symname + strlen(CRC_PFX), mod, crc, 611 export); 612 } 613 break; 614 case SHN_UNDEF: 615 /* undefined symbol */ 616 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && 617 ELF_ST_BIND(sym->st_info) != STB_WEAK) 618 break; 619 if (ignore_undef_symbol(info, symname)) 620 break; 621 /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */ 622 #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER) 623 /* add compatibility with older glibc */ 624 #ifndef STT_SPARC_REGISTER 625 #define STT_SPARC_REGISTER STT_REGISTER 626 #endif 627 if (info->hdr->e_machine == EM_SPARC || 628 info->hdr->e_machine == EM_SPARCV9) { 629 /* Ignore register directives. */ 630 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER) 631 break; 632 if (symname[0] == '.') { 633 char *munged = strdup(symname); 634 munged[0] = '_'; 635 munged[1] = toupper(munged[1]); 636 symname = munged; 637 } 638 } 639 #endif 640 641 #ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX 642 if (symname[0] != '_') 643 break; 644 else 645 symname++; 646 #endif 647 mod->unres = alloc_symbol(symname, 648 ELF_ST_BIND(sym->st_info) == STB_WEAK, 649 mod->unres); 650 break; 651 default: 652 /* All exported symbols */ 653 if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) { 654 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod, 655 export); 656 } 657 if (strcmp(symname, VMLINUX_SYMBOL_STR(init_module)) == 0) 658 mod->has_init = 1; 659 if (strcmp(symname, VMLINUX_SYMBOL_STR(cleanup_module)) == 0) 660 mod->has_cleanup = 1; 661 break; 662 } 663 } 664 665 /** 666 * Parse tag=value strings from .modinfo section 667 **/ 668 static char *next_string(char *string, unsigned long *secsize) 669 { 670 /* Skip non-zero chars */ 671 while (string[0]) { 672 string++; 673 if ((*secsize)-- <= 1) 674 return NULL; 675 } 676 677 /* Skip any zero padding. */ 678 while (!string[0]) { 679 string++; 680 if ((*secsize)-- <= 1) 681 return NULL; 682 } 683 return string; 684 } 685 686 static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len, 687 const char *tag, char *info) 688 { 689 char *p; 690 unsigned int taglen = strlen(tag); 691 unsigned long size = modinfo_len; 692 693 if (info) { 694 size -= info - (char *)modinfo; 695 modinfo = next_string(info, &size); 696 } 697 698 for (p = modinfo; p; p = next_string(p, &size)) { 699 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') 700 return p + taglen + 1; 701 } 702 return NULL; 703 } 704 705 static char *get_modinfo(void *modinfo, unsigned long modinfo_len, 706 const char *tag) 707 708 { 709 return get_next_modinfo(modinfo, modinfo_len, tag, NULL); 710 } 711 712 /** 713 * Test if string s ends in string sub 714 * return 0 if match 715 **/ 716 static int strrcmp(const char *s, const char *sub) 717 { 718 int slen, sublen; 719 720 if (!s || !sub) 721 return 1; 722 723 slen = strlen(s); 724 sublen = strlen(sub); 725 726 if ((slen == 0) || (sublen == 0)) 727 return 1; 728 729 if (sublen > slen) 730 return 1; 731 732 return memcmp(s + slen - sublen, sub, sublen); 733 } 734 735 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) 736 { 737 if (sym) 738 return elf->strtab + sym->st_name; 739 else 740 return "(unknown)"; 741 } 742 743 static const char *sec_name(struct elf_info *elf, int secindex) 744 { 745 Elf_Shdr *sechdrs = elf->sechdrs; 746 return (void *)elf->hdr + 747 elf->sechdrs[elf->secindex_strings].sh_offset + 748 sechdrs[secindex].sh_name; 749 } 750 751 static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr) 752 { 753 return (void *)elf->hdr + 754 elf->sechdrs[elf->secindex_strings].sh_offset + 755 sechdr->sh_name; 756 } 757 758 /* if sym is empty or point to a string 759 * like ".[0-9]+" then return 1. 760 * This is the optional prefix added by ld to some sections 761 */ 762 static int number_prefix(const char *sym) 763 { 764 if (*sym++ == '\0') 765 return 1; 766 if (*sym != '.') 767 return 0; 768 do { 769 char c = *sym++; 770 if (c < '0' || c > '9') 771 return 0; 772 } while (*sym); 773 return 1; 774 } 775 776 /* The pattern is an array of simple patterns. 777 * "foo" will match an exact string equal to "foo" 778 * "*foo" will match a string that ends with "foo" 779 * "foo*" will match a string that begins with "foo" 780 * "foo$" will match a string equal to "foo" or "foo.1" 781 * where the '1' can be any number including several digits. 782 * The $ syntax is for sections where ld append a dot number 783 * to make section name unique. 784 */ 785 static int match(const char *sym, const char * const pat[]) 786 { 787 const char *p; 788 while (*pat) { 789 p = *pat++; 790 const char *endp = p + strlen(p) - 1; 791 792 /* "*foo" */ 793 if (*p == '*') { 794 if (strrcmp(sym, p + 1) == 0) 795 return 1; 796 } 797 /* "foo*" */ 798 else if (*endp == '*') { 799 if (strncmp(sym, p, strlen(p) - 1) == 0) 800 return 1; 801 } 802 /* "foo$" */ 803 else if (*endp == '$') { 804 if (strncmp(sym, p, strlen(p) - 1) == 0) { 805 if (number_prefix(sym + strlen(p) - 1)) 806 return 1; 807 } 808 } 809 /* no wildcards */ 810 else { 811 if (strcmp(p, sym) == 0) 812 return 1; 813 } 814 } 815 /* no match */ 816 return 0; 817 } 818 819 /* sections that we do not want to do full section mismatch check on */ 820 static const char *section_white_list[] = 821 { 822 ".comment*", 823 ".debug*", 824 ".zdebug*", /* Compressed debug sections. */ 825 ".GCC-command-line", /* mn10300 */ 826 ".GCC.command.line", /* record-gcc-switches, non mn10300 */ 827 ".mdebug*", /* alpha, score, mips etc. */ 828 ".pdr", /* alpha, score, mips etc. */ 829 ".stab*", 830 ".note*", 831 ".got*", 832 ".toc*", 833 ".xt.prop", /* xtensa */ 834 ".xt.lit", /* xtensa */ 835 ".arcextmap*", /* arc */ 836 ".gnu.linkonce.arcext*", /* arc : modules */ 837 NULL 838 }; 839 840 /* 841 * This is used to find sections missing the SHF_ALLOC flag. 842 * The cause of this is often a section specified in assembler 843 * without "ax" / "aw". 844 */ 845 static void check_section(const char *modname, struct elf_info *elf, 846 Elf_Shdr *sechdr) 847 { 848 const char *sec = sech_name(elf, sechdr); 849 850 if (sechdr->sh_type == SHT_PROGBITS && 851 !(sechdr->sh_flags & SHF_ALLOC) && 852 !match(sec, section_white_list)) { 853 warn("%s (%s): unexpected non-allocatable section.\n" 854 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n" 855 "Note that for example <linux/init.h> contains\n" 856 "section definitions for use in .S files.\n\n", 857 modname, sec); 858 } 859 } 860 861 862 863 #define ALL_INIT_DATA_SECTIONS \ 864 ".init.setup$", ".init.rodata$", ".meminit.rodata$", \ 865 ".init.data$", ".meminit.data$" 866 #define ALL_EXIT_DATA_SECTIONS \ 867 ".exit.data$", ".memexit.data$" 868 869 #define ALL_INIT_TEXT_SECTIONS \ 870 ".init.text$", ".meminit.text$" 871 #define ALL_EXIT_TEXT_SECTIONS \ 872 ".exit.text$", ".memexit.text$" 873 874 #define ALL_PCI_INIT_SECTIONS \ 875 ".pci_fixup_early$", ".pci_fixup_header$", ".pci_fixup_final$", \ 876 ".pci_fixup_enable$", ".pci_fixup_resume$", \ 877 ".pci_fixup_resume_early$", ".pci_fixup_suspend$" 878 879 #define ALL_XXXINIT_SECTIONS MEM_INIT_SECTIONS 880 #define ALL_XXXEXIT_SECTIONS MEM_EXIT_SECTIONS 881 882 #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS 883 #define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS 884 885 #define DATA_SECTIONS ".data$", ".data.rel$" 886 #define TEXT_SECTIONS ".text$", ".text.unlikely$" 887 888 #define INIT_SECTIONS ".init.*" 889 #define MEM_INIT_SECTIONS ".meminit.*" 890 891 #define EXIT_SECTIONS ".exit.*" 892 #define MEM_EXIT_SECTIONS ".memexit.*" 893 894 /* init data sections */ 895 static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL }; 896 897 /* all init sections */ 898 static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL }; 899 900 /* All init and exit sections (code + data) */ 901 static const char *init_exit_sections[] = 902 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }; 903 904 /* data section */ 905 static const char *data_sections[] = { DATA_SECTIONS, NULL }; 906 907 908 /* symbols in .data that may refer to init/exit sections */ 909 #define DEFAULT_SYMBOL_WHITE_LIST \ 910 "*driver", \ 911 "*_template", /* scsi uses *_template a lot */ \ 912 "*_timer", /* arm uses ops structures named _timer a lot */ \ 913 "*_sht", /* scsi also used *_sht to some extent */ \ 914 "*_ops", \ 915 "*_probe", \ 916 "*_probe_one", \ 917 "*_console" 918 919 static const char *head_sections[] = { ".head.text*", NULL }; 920 static const char *linker_symbols[] = 921 { "__init_begin", "_sinittext", "_einittext", NULL }; 922 923 enum mismatch { 924 TEXT_TO_ANY_INIT, 925 DATA_TO_ANY_INIT, 926 TEXT_TO_ANY_EXIT, 927 DATA_TO_ANY_EXIT, 928 XXXINIT_TO_SOME_INIT, 929 XXXEXIT_TO_SOME_EXIT, 930 ANY_INIT_TO_ANY_EXIT, 931 ANY_EXIT_TO_ANY_INIT, 932 EXPORT_TO_INIT_EXIT, 933 }; 934 935 struct sectioncheck { 936 const char *fromsec[20]; 937 const char *tosec[20]; 938 enum mismatch mismatch; 939 const char *symbol_white_list[20]; 940 }; 941 942 const struct sectioncheck sectioncheck[] = { 943 /* Do not reference init/exit code/data from 944 * normal code and data 945 */ 946 { 947 .fromsec = { TEXT_SECTIONS, NULL }, 948 .tosec = { ALL_INIT_SECTIONS, NULL }, 949 .mismatch = TEXT_TO_ANY_INIT, 950 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 951 }, 952 { 953 .fromsec = { DATA_SECTIONS, NULL }, 954 .tosec = { ALL_XXXINIT_SECTIONS, NULL }, 955 .mismatch = DATA_TO_ANY_INIT, 956 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 957 }, 958 { 959 .fromsec = { DATA_SECTIONS, NULL }, 960 .tosec = { INIT_SECTIONS, NULL }, 961 .mismatch = DATA_TO_ANY_INIT, 962 .symbol_white_list = { 963 "*_template", "*_timer", "*_sht", "*_ops", 964 "*_probe", "*_probe_one", "*_console", NULL 965 }, 966 }, 967 { 968 .fromsec = { TEXT_SECTIONS, NULL }, 969 .tosec = { ALL_EXIT_SECTIONS, NULL }, 970 .mismatch = TEXT_TO_ANY_EXIT, 971 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 972 }, 973 { 974 .fromsec = { DATA_SECTIONS, NULL }, 975 .tosec = { ALL_EXIT_SECTIONS, NULL }, 976 .mismatch = DATA_TO_ANY_EXIT, 977 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 978 }, 979 /* Do not reference init code/data from meminit code/data */ 980 { 981 .fromsec = { ALL_XXXINIT_SECTIONS, NULL }, 982 .tosec = { INIT_SECTIONS, NULL }, 983 .mismatch = XXXINIT_TO_SOME_INIT, 984 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 985 }, 986 /* Do not reference exit code/data from memexit code/data */ 987 { 988 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL }, 989 .tosec = { EXIT_SECTIONS, NULL }, 990 .mismatch = XXXEXIT_TO_SOME_EXIT, 991 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 992 }, 993 /* Do not use exit code/data from init code */ 994 { 995 .fromsec = { ALL_INIT_SECTIONS, NULL }, 996 .tosec = { ALL_EXIT_SECTIONS, NULL }, 997 .mismatch = ANY_INIT_TO_ANY_EXIT, 998 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 999 }, 1000 /* Do not use init code/data from exit code */ 1001 { 1002 .fromsec = { ALL_EXIT_SECTIONS, NULL }, 1003 .tosec = { ALL_INIT_SECTIONS, NULL }, 1004 .mismatch = ANY_EXIT_TO_ANY_INIT, 1005 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 1006 }, 1007 { 1008 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL }, 1009 .tosec = { INIT_SECTIONS, NULL }, 1010 .mismatch = ANY_INIT_TO_ANY_EXIT, 1011 .symbol_white_list = { NULL }, 1012 }, 1013 /* Do not export init/exit functions or data */ 1014 { 1015 .fromsec = { "__ksymtab*", NULL }, 1016 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL }, 1017 .mismatch = EXPORT_TO_INIT_EXIT, 1018 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, 1019 } 1020 }; 1021 1022 static const struct sectioncheck *section_mismatch( 1023 const char *fromsec, const char *tosec) 1024 { 1025 int i; 1026 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck); 1027 const struct sectioncheck *check = §ioncheck[0]; 1028 1029 for (i = 0; i < elems; i++) { 1030 if (match(fromsec, check->fromsec) && 1031 match(tosec, check->tosec)) 1032 return check; 1033 check++; 1034 } 1035 return NULL; 1036 } 1037 1038 /** 1039 * Whitelist to allow certain references to pass with no warning. 1040 * 1041 * Pattern 1: 1042 * If a module parameter is declared __initdata and permissions=0 1043 * then this is legal despite the warning generated. 1044 * We cannot see value of permissions here, so just ignore 1045 * this pattern. 1046 * The pattern is identified by: 1047 * tosec = .init.data 1048 * fromsec = .data* 1049 * atsym =__param* 1050 * 1051 * Pattern 1a: 1052 * module_param_call() ops can refer to __init set function if permissions=0 1053 * The pattern is identified by: 1054 * tosec = .init.text 1055 * fromsec = .data* 1056 * atsym = __param_ops_* 1057 * 1058 * Pattern 2: 1059 * Many drivers utilise a *driver container with references to 1060 * add, remove, probe functions etc. 1061 * the pattern is identified by: 1062 * tosec = init or exit section 1063 * fromsec = data section 1064 * atsym = *driver, *_template, *_sht, *_ops, *_probe, 1065 * *probe_one, *_console, *_timer 1066 * 1067 * Pattern 3: 1068 * Whitelist all references from .head.text to any init section 1069 * 1070 * Pattern 4: 1071 * Some symbols belong to init section but still it is ok to reference 1072 * these from non-init sections as these symbols don't have any memory 1073 * allocated for them and symbol address and value are same. So even 1074 * if init section is freed, its ok to reference those symbols. 1075 * For ex. symbols marking the init section boundaries. 1076 * This pattern is identified by 1077 * refsymname = __init_begin, _sinittext, _einittext 1078 * 1079 **/ 1080 static int secref_whitelist(const struct sectioncheck *mismatch, 1081 const char *fromsec, const char *fromsym, 1082 const char *tosec, const char *tosym) 1083 { 1084 /* Check for pattern 1 */ 1085 if (match(tosec, init_data_sections) && 1086 match(fromsec, data_sections) && 1087 (strncmp(fromsym, "__param", strlen("__param")) == 0)) 1088 return 0; 1089 1090 /* Check for pattern 1a */ 1091 if (strcmp(tosec, ".init.text") == 0 && 1092 match(fromsec, data_sections) && 1093 (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0)) 1094 return 0; 1095 1096 /* Check for pattern 2 */ 1097 if (match(tosec, init_exit_sections) && 1098 match(fromsec, data_sections) && 1099 match(fromsym, mismatch->symbol_white_list)) 1100 return 0; 1101 1102 /* Check for pattern 3 */ 1103 if (match(fromsec, head_sections) && 1104 match(tosec, init_sections)) 1105 return 0; 1106 1107 /* Check for pattern 4 */ 1108 if (match(tosym, linker_symbols)) 1109 return 0; 1110 1111 return 1; 1112 } 1113 1114 /** 1115 * Find symbol based on relocation record info. 1116 * In some cases the symbol supplied is a valid symbol so 1117 * return refsym. If st_name != 0 we assume this is a valid symbol. 1118 * In other cases the symbol needs to be looked up in the symbol table 1119 * based on section and address. 1120 * **/ 1121 static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr, 1122 Elf_Sym *relsym) 1123 { 1124 Elf_Sym *sym; 1125 Elf_Sym *near = NULL; 1126 Elf64_Sword distance = 20; 1127 Elf64_Sword d; 1128 unsigned int relsym_secindex; 1129 1130 if (relsym->st_name != 0) 1131 return relsym; 1132 1133 relsym_secindex = get_secindex(elf, relsym); 1134 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { 1135 if (get_secindex(elf, sym) != relsym_secindex) 1136 continue; 1137 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION) 1138 continue; 1139 if (sym->st_value == addr) 1140 return sym; 1141 /* Find a symbol nearby - addr are maybe negative */ 1142 d = sym->st_value - addr; 1143 if (d < 0) 1144 d = addr - sym->st_value; 1145 if (d < distance) { 1146 distance = d; 1147 near = sym; 1148 } 1149 } 1150 /* We need a close match */ 1151 if (distance < 20) 1152 return near; 1153 else 1154 return NULL; 1155 } 1156 1157 static inline int is_arm_mapping_symbol(const char *str) 1158 { 1159 return str[0] == '$' && strchr("atd", str[1]) 1160 && (str[2] == '\0' || str[2] == '.'); 1161 } 1162 1163 /* 1164 * If there's no name there, ignore it; likewise, ignore it if it's 1165 * one of the magic symbols emitted used by current ARM tools. 1166 * 1167 * Otherwise if find_symbols_between() returns those symbols, they'll 1168 * fail the whitelist tests and cause lots of false alarms ... fixable 1169 * only by merging __exit and __init sections into __text, bloating 1170 * the kernel (which is especially evil on embedded platforms). 1171 */ 1172 static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym) 1173 { 1174 const char *name = elf->strtab + sym->st_name; 1175 1176 if (!name || !strlen(name)) 1177 return 0; 1178 return !is_arm_mapping_symbol(name); 1179 } 1180 1181 /* 1182 * Find symbols before or equal addr and after addr - in the section sec. 1183 * If we find two symbols with equal offset prefer one with a valid name. 1184 * The ELF format may have a better way to detect what type of symbol 1185 * it is, but this works for now. 1186 **/ 1187 static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr, 1188 const char *sec) 1189 { 1190 Elf_Sym *sym; 1191 Elf_Sym *near = NULL; 1192 Elf_Addr distance = ~0; 1193 1194 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { 1195 const char *symsec; 1196 1197 if (is_shndx_special(sym->st_shndx)) 1198 continue; 1199 symsec = sec_name(elf, get_secindex(elf, sym)); 1200 if (strcmp(symsec, sec) != 0) 1201 continue; 1202 if (!is_valid_name(elf, sym)) 1203 continue; 1204 if (sym->st_value <= addr) { 1205 if ((addr - sym->st_value) < distance) { 1206 distance = addr - sym->st_value; 1207 near = sym; 1208 } else if ((addr - sym->st_value) == distance) { 1209 near = sym; 1210 } 1211 } 1212 } 1213 return near; 1214 } 1215 1216 /* 1217 * Convert a section name to the function/data attribute 1218 * .init.text => __init 1219 * .memexitconst => __memconst 1220 * etc. 1221 * 1222 * The memory of returned value has been allocated on a heap. The user of this 1223 * method should free it after usage. 1224 */ 1225 static char *sec2annotation(const char *s) 1226 { 1227 if (match(s, init_exit_sections)) { 1228 char *p = malloc(20); 1229 char *r = p; 1230 1231 *p++ = '_'; 1232 *p++ = '_'; 1233 if (*s == '.') 1234 s++; 1235 while (*s && *s != '.') 1236 *p++ = *s++; 1237 *p = '\0'; 1238 if (*s == '.') 1239 s++; 1240 if (strstr(s, "rodata") != NULL) 1241 strcat(p, "const "); 1242 else if (strstr(s, "data") != NULL) 1243 strcat(p, "data "); 1244 else 1245 strcat(p, " "); 1246 return r; 1247 } else { 1248 return strdup(""); 1249 } 1250 } 1251 1252 static int is_function(Elf_Sym *sym) 1253 { 1254 if (sym) 1255 return ELF_ST_TYPE(sym->st_info) == STT_FUNC; 1256 else 1257 return -1; 1258 } 1259 1260 static void print_section_list(const char * const list[20]) 1261 { 1262 const char *const *s = list; 1263 1264 while (*s) { 1265 fprintf(stderr, "%s", *s); 1266 s++; 1267 if (*s) 1268 fprintf(stderr, ", "); 1269 } 1270 fprintf(stderr, "\n"); 1271 } 1272 1273 /* 1274 * Print a warning about a section mismatch. 1275 * Try to find symbols near it so user can find it. 1276 * Check whitelist before warning - it may be a false positive. 1277 */ 1278 static void report_sec_mismatch(const char *modname, 1279 const struct sectioncheck *mismatch, 1280 const char *fromsec, 1281 unsigned long long fromaddr, 1282 const char *fromsym, 1283 int from_is_func, 1284 const char *tosec, const char *tosym, 1285 int to_is_func) 1286 { 1287 const char *from, *from_p; 1288 const char *to, *to_p; 1289 char *prl_from; 1290 char *prl_to; 1291 1292 switch (from_is_func) { 1293 case 0: from = "variable"; from_p = ""; break; 1294 case 1: from = "function"; from_p = "()"; break; 1295 default: from = "(unknown reference)"; from_p = ""; break; 1296 } 1297 switch (to_is_func) { 1298 case 0: to = "variable"; to_p = ""; break; 1299 case 1: to = "function"; to_p = "()"; break; 1300 default: to = "(unknown reference)"; to_p = ""; break; 1301 } 1302 1303 sec_mismatch_count++; 1304 if (!sec_mismatch_verbose) 1305 return; 1306 1307 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s " 1308 "to the %s %s:%s%s\n", 1309 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec, 1310 tosym, to_p); 1311 1312 switch (mismatch->mismatch) { 1313 case TEXT_TO_ANY_INIT: 1314 prl_from = sec2annotation(fromsec); 1315 prl_to = sec2annotation(tosec); 1316 fprintf(stderr, 1317 "The function %s%s() references\n" 1318 "the %s %s%s%s.\n" 1319 "This is often because %s lacks a %s\n" 1320 "annotation or the annotation of %s is wrong.\n", 1321 prl_from, fromsym, 1322 to, prl_to, tosym, to_p, 1323 fromsym, prl_to, tosym); 1324 free(prl_from); 1325 free(prl_to); 1326 break; 1327 case DATA_TO_ANY_INIT: { 1328 prl_to = sec2annotation(tosec); 1329 fprintf(stderr, 1330 "The variable %s references\n" 1331 "the %s %s%s%s\n" 1332 "If the reference is valid then annotate the\n" 1333 "variable with __init* or __refdata (see linux/init.h) " 1334 "or name the variable:\n", 1335 fromsym, to, prl_to, tosym, to_p); 1336 print_section_list(mismatch->symbol_white_list); 1337 free(prl_to); 1338 break; 1339 } 1340 case TEXT_TO_ANY_EXIT: 1341 prl_to = sec2annotation(tosec); 1342 fprintf(stderr, 1343 "The function %s() references a %s in an exit section.\n" 1344 "Often the %s %s%s has valid usage outside the exit section\n" 1345 "and the fix is to remove the %sannotation of %s.\n", 1346 fromsym, to, to, tosym, to_p, prl_to, tosym); 1347 free(prl_to); 1348 break; 1349 case DATA_TO_ANY_EXIT: { 1350 prl_to = sec2annotation(tosec); 1351 fprintf(stderr, 1352 "The variable %s references\n" 1353 "the %s %s%s%s\n" 1354 "If the reference is valid then annotate the\n" 1355 "variable with __exit* (see linux/init.h) or " 1356 "name the variable:\n", 1357 fromsym, to, prl_to, tosym, to_p); 1358 print_section_list(mismatch->symbol_white_list); 1359 free(prl_to); 1360 break; 1361 } 1362 case XXXINIT_TO_SOME_INIT: 1363 case XXXEXIT_TO_SOME_EXIT: 1364 prl_from = sec2annotation(fromsec); 1365 prl_to = sec2annotation(tosec); 1366 fprintf(stderr, 1367 "The %s %s%s%s references\n" 1368 "a %s %s%s%s.\n" 1369 "If %s is only used by %s then\n" 1370 "annotate %s with a matching annotation.\n", 1371 from, prl_from, fromsym, from_p, 1372 to, prl_to, tosym, to_p, 1373 tosym, fromsym, tosym); 1374 free(prl_from); 1375 free(prl_to); 1376 break; 1377 case ANY_INIT_TO_ANY_EXIT: 1378 prl_from = sec2annotation(fromsec); 1379 prl_to = sec2annotation(tosec); 1380 fprintf(stderr, 1381 "The %s %s%s%s references\n" 1382 "a %s %s%s%s.\n" 1383 "This is often seen when error handling " 1384 "in the init function\n" 1385 "uses functionality in the exit path.\n" 1386 "The fix is often to remove the %sannotation of\n" 1387 "%s%s so it may be used outside an exit section.\n", 1388 from, prl_from, fromsym, from_p, 1389 to, prl_to, tosym, to_p, 1390 prl_to, tosym, to_p); 1391 free(prl_from); 1392 free(prl_to); 1393 break; 1394 case ANY_EXIT_TO_ANY_INIT: 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 exit function\n" 1402 "uses functionality in the init path.\n" 1403 "The fix is often to remove the %sannotation of\n" 1404 "%s%s so it may be used outside an init 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 EXPORT_TO_INIT_EXIT: 1412 prl_to = sec2annotation(tosec); 1413 fprintf(stderr, 1414 "The symbol %s is exported and annotated %s\n" 1415 "Fix this by removing the %sannotation of %s " 1416 "or drop the export.\n", 1417 tosym, prl_to, prl_to, tosym); 1418 free(prl_to); 1419 break; 1420 } 1421 fprintf(stderr, "\n"); 1422 } 1423 1424 static void check_section_mismatch(const char *modname, struct elf_info *elf, 1425 Elf_Rela *r, Elf_Sym *sym, const char *fromsec) 1426 { 1427 const char *tosec; 1428 const struct sectioncheck *mismatch; 1429 1430 tosec = sec_name(elf, get_secindex(elf, sym)); 1431 mismatch = section_mismatch(fromsec, tosec); 1432 if (mismatch) { 1433 Elf_Sym *to; 1434 Elf_Sym *from; 1435 const char *tosym; 1436 const char *fromsym; 1437 1438 from = find_elf_symbol2(elf, r->r_offset, fromsec); 1439 fromsym = sym_name(elf, from); 1440 to = find_elf_symbol(elf, r->r_addend, sym); 1441 tosym = sym_name(elf, to); 1442 1443 /* check whitelist - we may ignore it */ 1444 if (secref_whitelist(mismatch, 1445 fromsec, fromsym, tosec, tosym)) { 1446 report_sec_mismatch(modname, mismatch, 1447 fromsec, r->r_offset, fromsym, 1448 is_function(from), tosec, tosym, 1449 is_function(to)); 1450 } 1451 } 1452 } 1453 1454 static unsigned int *reloc_location(struct elf_info *elf, 1455 Elf_Shdr *sechdr, Elf_Rela *r) 1456 { 1457 Elf_Shdr *sechdrs = elf->sechdrs; 1458 int section = sechdr->sh_info; 1459 1460 return (void *)elf->hdr + sechdrs[section].sh_offset + 1461 r->r_offset; 1462 } 1463 1464 static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1465 { 1466 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1467 unsigned int *location = reloc_location(elf, sechdr, r); 1468 1469 switch (r_typ) { 1470 case R_386_32: 1471 r->r_addend = TO_NATIVE(*location); 1472 break; 1473 case R_386_PC32: 1474 r->r_addend = TO_NATIVE(*location) + 4; 1475 /* For CONFIG_RELOCATABLE=y */ 1476 if (elf->hdr->e_type == ET_EXEC) 1477 r->r_addend += r->r_offset; 1478 break; 1479 } 1480 return 0; 1481 } 1482 1483 #ifndef R_ARM_CALL 1484 #define R_ARM_CALL 28 1485 #endif 1486 #ifndef R_ARM_JUMP24 1487 #define R_ARM_JUMP24 29 1488 #endif 1489 1490 static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1491 { 1492 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1493 1494 switch (r_typ) { 1495 case R_ARM_ABS32: 1496 /* From ARM ABI: (S + A) | T */ 1497 r->r_addend = (int)(long) 1498 (elf->symtab_start + ELF_R_SYM(r->r_info)); 1499 break; 1500 case R_ARM_PC24: 1501 case R_ARM_CALL: 1502 case R_ARM_JUMP24: 1503 /* From ARM ABI: ((S + A) | T) - P */ 1504 r->r_addend = (int)(long)(elf->hdr + 1505 sechdr->sh_offset + 1506 (r->r_offset - sechdr->sh_addr)); 1507 break; 1508 default: 1509 return 1; 1510 } 1511 return 0; 1512 } 1513 1514 static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) 1515 { 1516 unsigned int r_typ = ELF_R_TYPE(r->r_info); 1517 unsigned int *location = reloc_location(elf, sechdr, r); 1518 unsigned int inst; 1519 1520 if (r_typ == R_MIPS_HI16) 1521 return 1; /* skip this */ 1522 inst = TO_NATIVE(*location); 1523 switch (r_typ) { 1524 case R_MIPS_LO16: 1525 r->r_addend = inst & 0xffff; 1526 break; 1527 case R_MIPS_26: 1528 r->r_addend = (inst & 0x03ffffff) << 2; 1529 break; 1530 case R_MIPS_32: 1531 r->r_addend = inst; 1532 break; 1533 } 1534 return 0; 1535 } 1536 1537 static void section_rela(const char *modname, struct elf_info *elf, 1538 Elf_Shdr *sechdr) 1539 { 1540 Elf_Sym *sym; 1541 Elf_Rela *rela; 1542 Elf_Rela r; 1543 unsigned int r_sym; 1544 const char *fromsec; 1545 1546 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset; 1547 Elf_Rela *stop = (void *)start + sechdr->sh_size; 1548 1549 fromsec = sech_name(elf, sechdr); 1550 fromsec += strlen(".rela"); 1551 /* if from section (name) is know good then skip it */ 1552 if (match(fromsec, section_white_list)) 1553 return; 1554 1555 for (rela = start; rela < stop; rela++) { 1556 r.r_offset = TO_NATIVE(rela->r_offset); 1557 #if KERNEL_ELFCLASS == ELFCLASS64 1558 if (elf->hdr->e_machine == EM_MIPS) { 1559 unsigned int r_typ; 1560 r_sym = ELF64_MIPS_R_SYM(rela->r_info); 1561 r_sym = TO_NATIVE(r_sym); 1562 r_typ = ELF64_MIPS_R_TYPE(rela->r_info); 1563 r.r_info = ELF64_R_INFO(r_sym, r_typ); 1564 } else { 1565 r.r_info = TO_NATIVE(rela->r_info); 1566 r_sym = ELF_R_SYM(r.r_info); 1567 } 1568 #else 1569 r.r_info = TO_NATIVE(rela->r_info); 1570 r_sym = ELF_R_SYM(r.r_info); 1571 #endif 1572 r.r_addend = TO_NATIVE(rela->r_addend); 1573 sym = elf->symtab_start + r_sym; 1574 /* Skip special sections */ 1575 if (is_shndx_special(sym->st_shndx)) 1576 continue; 1577 check_section_mismatch(modname, elf, &r, sym, fromsec); 1578 } 1579 } 1580 1581 static void section_rel(const char *modname, struct elf_info *elf, 1582 Elf_Shdr *sechdr) 1583 { 1584 Elf_Sym *sym; 1585 Elf_Rel *rel; 1586 Elf_Rela r; 1587 unsigned int r_sym; 1588 const char *fromsec; 1589 1590 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset; 1591 Elf_Rel *stop = (void *)start + sechdr->sh_size; 1592 1593 fromsec = sech_name(elf, sechdr); 1594 fromsec += strlen(".rel"); 1595 /* if from section (name) is know good then skip it */ 1596 if (match(fromsec, section_white_list)) 1597 return; 1598 1599 for (rel = start; rel < stop; rel++) { 1600 r.r_offset = TO_NATIVE(rel->r_offset); 1601 #if KERNEL_ELFCLASS == ELFCLASS64 1602 if (elf->hdr->e_machine == EM_MIPS) { 1603 unsigned int r_typ; 1604 r_sym = ELF64_MIPS_R_SYM(rel->r_info); 1605 r_sym = TO_NATIVE(r_sym); 1606 r_typ = ELF64_MIPS_R_TYPE(rel->r_info); 1607 r.r_info = ELF64_R_INFO(r_sym, r_typ); 1608 } else { 1609 r.r_info = TO_NATIVE(rel->r_info); 1610 r_sym = ELF_R_SYM(r.r_info); 1611 } 1612 #else 1613 r.r_info = TO_NATIVE(rel->r_info); 1614 r_sym = ELF_R_SYM(r.r_info); 1615 #endif 1616 r.r_addend = 0; 1617 switch (elf->hdr->e_machine) { 1618 case EM_386: 1619 if (addend_386_rel(elf, sechdr, &r)) 1620 continue; 1621 break; 1622 case EM_ARM: 1623 if (addend_arm_rel(elf, sechdr, &r)) 1624 continue; 1625 break; 1626 case EM_MIPS: 1627 if (addend_mips_rel(elf, sechdr, &r)) 1628 continue; 1629 break; 1630 } 1631 sym = elf->symtab_start + r_sym; 1632 /* Skip special sections */ 1633 if (is_shndx_special(sym->st_shndx)) 1634 continue; 1635 check_section_mismatch(modname, elf, &r, sym, fromsec); 1636 } 1637 } 1638 1639 /** 1640 * A module includes a number of sections that are discarded 1641 * either when loaded or when used as built-in. 1642 * For loaded modules all functions marked __init and all data 1643 * marked __initdata will be discarded when the module has been initialized. 1644 * Likewise for modules used built-in the sections marked __exit 1645 * are discarded because __exit marked function are supposed to be called 1646 * only when a module is unloaded which never happens for built-in modules. 1647 * The check_sec_ref() function traverses all relocation records 1648 * to find all references to a section that reference a section that will 1649 * be discarded and warns about it. 1650 **/ 1651 static void check_sec_ref(struct module *mod, const char *modname, 1652 struct elf_info *elf) 1653 { 1654 int i; 1655 Elf_Shdr *sechdrs = elf->sechdrs; 1656 1657 /* Walk through all sections */ 1658 for (i = 0; i < elf->num_sections; i++) { 1659 check_section(modname, elf, &elf->sechdrs[i]); 1660 /* We want to process only relocation sections and not .init */ 1661 if (sechdrs[i].sh_type == SHT_RELA) 1662 section_rela(modname, elf, &elf->sechdrs[i]); 1663 else if (sechdrs[i].sh_type == SHT_REL) 1664 section_rel(modname, elf, &elf->sechdrs[i]); 1665 } 1666 } 1667 1668 static void read_symbols(char *modname) 1669 { 1670 const char *symname; 1671 char *version; 1672 char *license; 1673 struct module *mod; 1674 struct elf_info info = { }; 1675 Elf_Sym *sym; 1676 1677 if (!parse_elf(&info, modname)) 1678 return; 1679 1680 mod = new_module(modname); 1681 1682 /* When there's no vmlinux, don't print warnings about 1683 * unresolved symbols (since there'll be too many ;) */ 1684 if (is_vmlinux(modname)) { 1685 have_vmlinux = 1; 1686 mod->skip = 1; 1687 } 1688 1689 license = get_modinfo(info.modinfo, info.modinfo_len, "license"); 1690 if (info.modinfo && !license && !is_vmlinux(modname)) 1691 warn("modpost: missing MODULE_LICENSE() in %s\n" 1692 "see include/linux/module.h for " 1693 "more information\n", modname); 1694 while (license) { 1695 if (license_is_gpl_compatible(license)) 1696 mod->gpl_compatible = 1; 1697 else { 1698 mod->gpl_compatible = 0; 1699 break; 1700 } 1701 license = get_next_modinfo(info.modinfo, info.modinfo_len, 1702 "license", license); 1703 } 1704 1705 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { 1706 symname = info.strtab + sym->st_name; 1707 1708 handle_modversions(mod, &info, sym, symname); 1709 handle_moddevtable(mod, &info, sym, symname); 1710 } 1711 if (!is_vmlinux(modname) || 1712 (is_vmlinux(modname) && vmlinux_section_warnings)) 1713 check_sec_ref(mod, modname, &info); 1714 1715 version = get_modinfo(info.modinfo, info.modinfo_len, "version"); 1716 if (version) 1717 maybe_frob_rcs_version(modname, version, info.modinfo, 1718 version - (char *)info.hdr); 1719 if (version || (all_versions && !is_vmlinux(modname))) 1720 get_src_version(modname, mod->srcversion, 1721 sizeof(mod->srcversion)-1); 1722 1723 parse_elf_finish(&info); 1724 1725 /* Our trick to get versioning for module struct etc. - it's 1726 * never passed as an argument to an exported function, so 1727 * the automatic versioning doesn't pick it up, but it's really 1728 * important anyhow */ 1729 if (modversions) 1730 mod->unres = alloc_symbol("module_layout", 0, mod->unres); 1731 } 1732 1733 static void read_symbols_from_files(const char *filename) 1734 { 1735 FILE *in = stdin; 1736 char fname[PATH_MAX]; 1737 1738 if (strcmp(filename, "-") != 0) { 1739 in = fopen(filename, "r"); 1740 if (!in) 1741 fatal("Can't open filenames file %s: %m", filename); 1742 } 1743 1744 while (fgets(fname, PATH_MAX, in) != NULL) { 1745 if (strends(fname, "\n")) 1746 fname[strlen(fname)-1] = '\0'; 1747 read_symbols(fname); 1748 } 1749 1750 if (in != stdin) 1751 fclose(in); 1752 } 1753 1754 #define SZ 500 1755 1756 /* We first write the generated file into memory using the 1757 * following helper, then compare to the file on disk and 1758 * only update the later if anything changed */ 1759 1760 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf, 1761 const char *fmt, ...) 1762 { 1763 char tmp[SZ]; 1764 int len; 1765 va_list ap; 1766 1767 va_start(ap, fmt); 1768 len = vsnprintf(tmp, SZ, fmt, ap); 1769 buf_write(buf, tmp, len); 1770 va_end(ap); 1771 } 1772 1773 void buf_write(struct buffer *buf, const char *s, int len) 1774 { 1775 if (buf->size - buf->pos < len) { 1776 buf->size += len + SZ; 1777 buf->p = realloc(buf->p, buf->size); 1778 } 1779 strncpy(buf->p + buf->pos, s, len); 1780 buf->pos += len; 1781 } 1782 1783 static void check_for_gpl_usage(enum export exp, const char *m, const char *s) 1784 { 1785 const char *e = is_vmlinux(m) ?"":".ko"; 1786 1787 switch (exp) { 1788 case export_gpl: 1789 fatal("modpost: GPL-incompatible module %s%s " 1790 "uses GPL-only symbol '%s'\n", m, e, s); 1791 break; 1792 case export_unused_gpl: 1793 fatal("modpost: GPL-incompatible module %s%s " 1794 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s); 1795 break; 1796 case export_gpl_future: 1797 warn("modpost: GPL-incompatible module %s%s " 1798 "uses future GPL-only symbol '%s'\n", m, e, s); 1799 break; 1800 case export_plain: 1801 case export_unused: 1802 case export_unknown: 1803 /* ignore */ 1804 break; 1805 } 1806 } 1807 1808 static void check_for_unused(enum export exp, const char *m, const char *s) 1809 { 1810 const char *e = is_vmlinux(m) ?"":".ko"; 1811 1812 switch (exp) { 1813 case export_unused: 1814 case export_unused_gpl: 1815 warn("modpost: module %s%s " 1816 "uses symbol '%s' marked UNUSED\n", m, e, s); 1817 break; 1818 default: 1819 /* ignore */ 1820 break; 1821 } 1822 } 1823 1824 static void check_exports(struct module *mod) 1825 { 1826 struct symbol *s, *exp; 1827 1828 for (s = mod->unres; s; s = s->next) { 1829 const char *basename; 1830 exp = find_symbol(s->name); 1831 if (!exp || exp->module == mod) 1832 continue; 1833 basename = strrchr(mod->name, '/'); 1834 if (basename) 1835 basename++; 1836 else 1837 basename = mod->name; 1838 if (!mod->gpl_compatible) 1839 check_for_gpl_usage(exp->export, basename, exp->name); 1840 check_for_unused(exp->export, basename, exp->name); 1841 } 1842 } 1843 1844 /** 1845 * Header for the generated file 1846 **/ 1847 static void add_header(struct buffer *b, struct module *mod) 1848 { 1849 buf_printf(b, "#include <linux/module.h>\n"); 1850 buf_printf(b, "#include <linux/vermagic.h>\n"); 1851 buf_printf(b, "#include <linux/compiler.h>\n"); 1852 buf_printf(b, "\n"); 1853 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n"); 1854 buf_printf(b, "\n"); 1855 buf_printf(b, "struct module __this_module\n"); 1856 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n"); 1857 buf_printf(b, "\t.name = KBUILD_MODNAME,\n"); 1858 if (mod->has_init) 1859 buf_printf(b, "\t.init = init_module,\n"); 1860 if (mod->has_cleanup) 1861 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n" 1862 "\t.exit = cleanup_module,\n" 1863 "#endif\n"); 1864 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n"); 1865 buf_printf(b, "};\n"); 1866 } 1867 1868 static void add_intree_flag(struct buffer *b, int is_intree) 1869 { 1870 if (is_intree) 1871 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n"); 1872 } 1873 1874 static void add_staging_flag(struct buffer *b, const char *name) 1875 { 1876 static const char *staging_dir = "drivers/staging"; 1877 1878 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0) 1879 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); 1880 } 1881 1882 /** 1883 * Record CRCs for unresolved symbols 1884 **/ 1885 static int add_versions(struct buffer *b, struct module *mod) 1886 { 1887 struct symbol *s, *exp; 1888 int err = 0; 1889 1890 for (s = mod->unres; s; s = s->next) { 1891 exp = find_symbol(s->name); 1892 if (!exp || exp->module == mod) { 1893 if (have_vmlinux && !s->weak) { 1894 if (warn_unresolved) { 1895 warn("\"%s\" [%s.ko] undefined!\n", 1896 s->name, mod->name); 1897 } else { 1898 merror("\"%s\" [%s.ko] undefined!\n", 1899 s->name, mod->name); 1900 err = 1; 1901 } 1902 } 1903 continue; 1904 } 1905 s->module = exp->module; 1906 s->crc_valid = exp->crc_valid; 1907 s->crc = exp->crc; 1908 } 1909 1910 if (!modversions) 1911 return err; 1912 1913 buf_printf(b, "\n"); 1914 buf_printf(b, "static const struct modversion_info ____versions[]\n"); 1915 buf_printf(b, "__used\n"); 1916 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n"); 1917 1918 for (s = mod->unres; s; s = s->next) { 1919 if (!s->module) 1920 continue; 1921 if (!s->crc_valid) { 1922 warn("\"%s\" [%s.ko] has no CRC!\n", 1923 s->name, mod->name); 1924 continue; 1925 } 1926 buf_printf(b, "\t{ %#8x, __VMLINUX_SYMBOL_STR(%s) },\n", 1927 s->crc, s->name); 1928 } 1929 1930 buf_printf(b, "};\n"); 1931 1932 return err; 1933 } 1934 1935 static void add_depends(struct buffer *b, struct module *mod, 1936 struct module *modules) 1937 { 1938 struct symbol *s; 1939 struct module *m; 1940 int first = 1; 1941 1942 for (m = modules; m; m = m->next) 1943 m->seen = is_vmlinux(m->name); 1944 1945 buf_printf(b, "\n"); 1946 buf_printf(b, "static const char __module_depends[]\n"); 1947 buf_printf(b, "__used\n"); 1948 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n"); 1949 buf_printf(b, "\"depends="); 1950 for (s = mod->unres; s; s = s->next) { 1951 const char *p; 1952 if (!s->module) 1953 continue; 1954 1955 if (s->module->seen) 1956 continue; 1957 1958 s->module->seen = 1; 1959 p = strrchr(s->module->name, '/'); 1960 if (p) 1961 p++; 1962 else 1963 p = s->module->name; 1964 buf_printf(b, "%s%s", first ? "" : ",", p); 1965 first = 0; 1966 } 1967 buf_printf(b, "\";\n"); 1968 } 1969 1970 static void add_srcversion(struct buffer *b, struct module *mod) 1971 { 1972 if (mod->srcversion[0]) { 1973 buf_printf(b, "\n"); 1974 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n", 1975 mod->srcversion); 1976 } 1977 } 1978 1979 static void write_if_changed(struct buffer *b, const char *fname) 1980 { 1981 char *tmp; 1982 FILE *file; 1983 struct stat st; 1984 1985 file = fopen(fname, "r"); 1986 if (!file) 1987 goto write; 1988 1989 if (fstat(fileno(file), &st) < 0) 1990 goto close_write; 1991 1992 if (st.st_size != b->pos) 1993 goto close_write; 1994 1995 tmp = NOFAIL(malloc(b->pos)); 1996 if (fread(tmp, 1, b->pos, file) != b->pos) 1997 goto free_write; 1998 1999 if (memcmp(tmp, b->p, b->pos) != 0) 2000 goto free_write; 2001 2002 free(tmp); 2003 fclose(file); 2004 return; 2005 2006 free_write: 2007 free(tmp); 2008 close_write: 2009 fclose(file); 2010 write: 2011 file = fopen(fname, "w"); 2012 if (!file) { 2013 perror(fname); 2014 exit(1); 2015 } 2016 if (fwrite(b->p, 1, b->pos, file) != b->pos) { 2017 perror(fname); 2018 exit(1); 2019 } 2020 fclose(file); 2021 } 2022 2023 /* parse Module.symvers file. line format: 2024 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something] 2025 **/ 2026 static void read_dump(const char *fname, unsigned int kernel) 2027 { 2028 unsigned long size, pos = 0; 2029 void *file = grab_file(fname, &size); 2030 char *line; 2031 2032 if (!file) 2033 /* No symbol versions, silently ignore */ 2034 return; 2035 2036 while ((line = get_next_line(&pos, file, size))) { 2037 char *symname, *modname, *d, *export, *end; 2038 unsigned int crc; 2039 struct module *mod; 2040 struct symbol *s; 2041 2042 if (!(symname = strchr(line, '\t'))) 2043 goto fail; 2044 *symname++ = '\0'; 2045 if (!(modname = strchr(symname, '\t'))) 2046 goto fail; 2047 *modname++ = '\0'; 2048 if ((export = strchr(modname, '\t')) != NULL) 2049 *export++ = '\0'; 2050 if (export && ((end = strchr(export, '\t')) != NULL)) 2051 *end = '\0'; 2052 crc = strtoul(line, &d, 16); 2053 if (*symname == '\0' || *modname == '\0' || *d != '\0') 2054 goto fail; 2055 mod = find_module(modname); 2056 if (!mod) { 2057 if (is_vmlinux(modname)) 2058 have_vmlinux = 1; 2059 mod = new_module(modname); 2060 mod->skip = 1; 2061 } 2062 s = sym_add_exported(symname, mod, export_no(export)); 2063 s->kernel = kernel; 2064 s->preloaded = 1; 2065 sym_update_crc(symname, mod, crc, export_no(export)); 2066 } 2067 return; 2068 fail: 2069 fatal("parse error in symbol dump file\n"); 2070 } 2071 2072 /* For normal builds always dump all symbols. 2073 * For external modules only dump symbols 2074 * that are not read from kernel Module.symvers. 2075 **/ 2076 static int dump_sym(struct symbol *sym) 2077 { 2078 if (!external_module) 2079 return 1; 2080 if (sym->vmlinux || sym->kernel) 2081 return 0; 2082 return 1; 2083 } 2084 2085 static void write_dump(const char *fname) 2086 { 2087 struct buffer buf = { }; 2088 struct symbol *symbol; 2089 int n; 2090 2091 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) { 2092 symbol = symbolhash[n]; 2093 while (symbol) { 2094 if (dump_sym(symbol)) 2095 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n", 2096 symbol->crc, symbol->name, 2097 symbol->module->name, 2098 export_str(symbol->export)); 2099 symbol = symbol->next; 2100 } 2101 } 2102 write_if_changed(&buf, fname); 2103 } 2104 2105 struct ext_sym_list { 2106 struct ext_sym_list *next; 2107 const char *file; 2108 }; 2109 2110 int main(int argc, char **argv) 2111 { 2112 struct module *mod; 2113 struct buffer buf = { }; 2114 char *kernel_read = NULL, *module_read = NULL; 2115 char *dump_write = NULL, *files_source = NULL; 2116 int opt; 2117 int err; 2118 struct ext_sym_list *extsym_iter; 2119 struct ext_sym_list *extsym_start = NULL; 2120 2121 while ((opt = getopt(argc, argv, "i:I:e:msST:o:awM:K:")) != -1) { 2122 switch (opt) { 2123 case 'i': 2124 kernel_read = optarg; 2125 break; 2126 case 'I': 2127 module_read = optarg; 2128 external_module = 1; 2129 break; 2130 case 'e': 2131 external_module = 1; 2132 extsym_iter = 2133 NOFAIL(malloc(sizeof(*extsym_iter))); 2134 extsym_iter->next = extsym_start; 2135 extsym_iter->file = optarg; 2136 extsym_start = extsym_iter; 2137 break; 2138 case 'm': 2139 modversions = 1; 2140 break; 2141 case 'o': 2142 dump_write = optarg; 2143 break; 2144 case 'a': 2145 all_versions = 1; 2146 break; 2147 case 's': 2148 vmlinux_section_warnings = 0; 2149 break; 2150 case 'S': 2151 sec_mismatch_verbose = 0; 2152 break; 2153 case 'T': 2154 files_source = optarg; 2155 break; 2156 case 'w': 2157 warn_unresolved = 1; 2158 break; 2159 default: 2160 exit(1); 2161 } 2162 } 2163 2164 if (kernel_read) 2165 read_dump(kernel_read, 1); 2166 if (module_read) 2167 read_dump(module_read, 0); 2168 while (extsym_start) { 2169 read_dump(extsym_start->file, 0); 2170 extsym_iter = extsym_start->next; 2171 free(extsym_start); 2172 extsym_start = extsym_iter; 2173 } 2174 2175 while (optind < argc) 2176 read_symbols(argv[optind++]); 2177 2178 if (files_source) 2179 read_symbols_from_files(files_source); 2180 2181 for (mod = modules; mod; mod = mod->next) { 2182 if (mod->skip) 2183 continue; 2184 check_exports(mod); 2185 } 2186 2187 err = 0; 2188 2189 for (mod = modules; mod; mod = mod->next) { 2190 char fname[strlen(mod->name) + 10]; 2191 2192 if (mod->skip) 2193 continue; 2194 2195 buf.pos = 0; 2196 2197 add_header(&buf, mod); 2198 add_intree_flag(&buf, !external_module); 2199 add_staging_flag(&buf, mod->name); 2200 err |= add_versions(&buf, mod); 2201 add_depends(&buf, mod, modules); 2202 add_moddevtable(&buf, mod); 2203 add_srcversion(&buf, mod); 2204 2205 sprintf(fname, "%s.mod.c", mod->name); 2206 write_if_changed(&buf, fname); 2207 } 2208 2209 if (dump_write) 2210 write_dump(dump_write); 2211 if (sec_mismatch_count && !sec_mismatch_verbose) 2212 warn("modpost: Found %d section mismatch(es).\n" 2213 "To see full details build your kernel with:\n" 2214 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n", 2215 sec_mismatch_count); 2216 2217 return err; 2218 } 2219