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