linux/scripts/mod/modpost.c
<<
>>
Prefs
   1/* Postprocess module symbol versions
   2 *
   3 * Copyright 2003       Kai Germaschewski
   4 * Copyright 2002-2004  Rusty Russell, IBM Corporation
   5 * Copyright 2006-2008  Sam Ravnborg
   6 * Based in part on module-init-tools/depmod.c,file2alias
   7 *
   8 * This software may be used and distributed according to the terms
   9 * of the GNU General Public License, incorporated herein by reference.
  10 *
  11 * Usage: modpost vmlinux module1.o module2.o ...
  12 */
  13
  14#define _GNU_SOURCE
  15#include <stdio.h>
  16#include <ctype.h>
  17#include <string.h>
  18#include "modpost.h"
  19#include "../../include/generated/autoconf.h"
  20#include "../../include/linux/license.h"
  21
  22/* Some toolchains use a `_' prefix for all user symbols. */
  23#ifdef CONFIG_SYMBOL_PREFIX
  24#define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX
  25#else
  26#define MODULE_SYMBOL_PREFIX ""
  27#endif
  28
  29
  30/* Are we using CONFIG_MODVERSIONS? */
  31int modversions = 0;
  32/* Warn about undefined symbols? (do so if we have vmlinux) */
  33int have_vmlinux = 0;
  34/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
  35static int all_versions = 0;
  36/* If we are modposting external module set to 1 */
  37static int external_module = 0;
  38/* Warn about section mismatch in vmlinux if set to 1 */
  39static int vmlinux_section_warnings = 1;
  40/* Only warn about unresolved symbols */
  41static int warn_unresolved = 0;
  42/* How a symbol is exported */
  43static int sec_mismatch_count = 0;
  44static int sec_mismatch_verbose = 1;
  45
  46enum export {
  47        export_plain,      export_unused,     export_gpl,
  48        export_unused_gpl, export_gpl_future, export_unknown
  49};
  50
  51#define PRINTF __attribute__ ((format (printf, 1, 2)))
  52
  53PRINTF void fatal(const char *fmt, ...)
  54{
  55        va_list arglist;
  56
  57        fprintf(stderr, "FATAL: ");
  58
  59        va_start(arglist, fmt);
  60        vfprintf(stderr, fmt, arglist);
  61        va_end(arglist);
  62
  63        exit(1);
  64}
  65
  66PRINTF void warn(const char *fmt, ...)
  67{
  68        va_list arglist;
  69
  70        fprintf(stderr, "WARNING: ");
  71
  72        va_start(arglist, fmt);
  73        vfprintf(stderr, fmt, arglist);
  74        va_end(arglist);
  75}
  76
  77PRINTF void merror(const char *fmt, ...)
  78{
  79        va_list arglist;
  80
  81        fprintf(stderr, "ERROR: ");
  82
  83        va_start(arglist, fmt);
  84        vfprintf(stderr, fmt, arglist);
  85        va_end(arglist);
  86}
  87
  88static int is_vmlinux(const char *modname)
  89{
  90        const char *myname;
  91
  92        myname = strrchr(modname, '/');
  93        if (myname)
  94                myname++;
  95        else
  96                myname = modname;
  97
  98        return (strcmp(myname, "vmlinux") == 0) ||
  99               (strcmp(myname, "vmlinux.o") == 0);
 100}
 101
 102void *do_nofail(void *ptr, const char *expr)
 103{
 104        if (!ptr)
 105                fatal("modpost: Memory allocation failure: %s.\n", expr);
 106
 107        return ptr;
 108}
 109
 110/* A list of all modules we processed */
 111static struct module *modules;
 112
 113static struct module *find_module(char *modname)
 114{
 115        struct module *mod;
 116
 117        for (mod = modules; mod; mod = mod->next)
 118                if (strcmp(mod->name, modname) == 0)
 119                        break;
 120        return mod;
 121}
 122
 123static struct module *new_module(char *modname)
 124{
 125        struct module *mod;
 126        char *p, *s;
 127
 128        mod = NOFAIL(malloc(sizeof(*mod)));
 129        memset(mod, 0, sizeof(*mod));
 130        p = NOFAIL(strdup(modname));
 131
 132        /* strip trailing .o */
 133        s = strrchr(p, '.');
 134        if (s != NULL)
 135                if (strcmp(s, ".o") == 0) {
 136                        *s = '\0';
 137                        mod->is_dot_o = 1;
 138                }
 139
 140        /* add to list */
 141        mod->name = p;
 142        mod->gpl_compatible = -1;
 143        mod->next = modules;
 144        modules = mod;
 145
 146        return mod;
 147}
 148
 149/* A hash of all exported symbols,
 150 * struct symbol is also used for lists of unresolved symbols */
 151
 152#define SYMBOL_HASH_SIZE 1024
 153
 154struct symbol {
 155        struct symbol *next;
 156        struct module *module;
 157        unsigned int crc;
 158        int crc_valid;
 159        unsigned int weak:1;
 160        unsigned int vmlinux:1;    /* 1 if symbol is defined in vmlinux */
 161        unsigned int kernel:1;     /* 1 if symbol is from kernel
 162                                    *  (only for external modules) **/
 163        unsigned int preloaded:1;  /* 1 if symbol from Module.symvers */
 164        enum export  export;       /* Type of export */
 165        char name[0];
 166};
 167
 168static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
 169
 170/* This is based on the hash agorithm from gdbm, via tdb */
 171static inline unsigned int tdb_hash(const char *name)
 172{
 173        unsigned value; /* Used to compute the hash value.  */
 174        unsigned   i;   /* Used to cycle through random values. */
 175
 176        /* Set the initial value from the key size. */
 177        for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
 178                value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
 179
 180        return (1103515243 * value + 12345);
 181}
 182
 183/**
 184 * Allocate a new symbols for use in the hash of exported symbols or
 185 * the list of unresolved symbols per module
 186 **/
 187static struct symbol *alloc_symbol(const char *name, unsigned int weak,
 188                                   struct symbol *next)
 189{
 190        struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
 191
 192        memset(s, 0, sizeof(*s));
 193        strcpy(s->name, name);
 194        s->weak = weak;
 195        s->next = next;
 196        return s;
 197}
 198
 199/* For the hash of exported symbols */
 200static struct symbol *new_symbol(const char *name, struct module *module,
 201                                 enum export export)
 202{
 203        unsigned int hash;
 204        struct symbol *new;
 205
 206        hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
 207        new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
 208        new->module = module;
 209        new->export = export;
 210        return new;
 211}
 212
 213static struct symbol *find_symbol(const char *name)
 214{
 215        struct symbol *s;
 216
 217        /* For our purposes, .foo matches foo.  PPC64 needs this. */
 218        if (name[0] == '.')
 219                name++;
 220
 221        for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
 222                if (strcmp(s->name, name) == 0)
 223                        return s;
 224        }
 225        return NULL;
 226}
 227
 228static struct {
 229        const char *str;
 230        enum export export;
 231} export_list[] = {
 232        { .str = "EXPORT_SYMBOL",            .export = export_plain },
 233        { .str = "EXPORT_UNUSED_SYMBOL",     .export = export_unused },
 234        { .str = "EXPORT_SYMBOL_GPL",        .export = export_gpl },
 235        { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
 236        { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
 237        { .str = "(unknown)",                .export = export_unknown },
 238};
 239
 240
 241static const char *export_str(enum export ex)
 242{
 243        return export_list[ex].str;
 244}
 245
 246static enum export export_no(const char *s)
 247{
 248        int i;
 249
 250        if (!s)
 251                return export_unknown;
 252        for (i = 0; export_list[i].export != export_unknown; i++) {
 253                if (strcmp(export_list[i].str, s) == 0)
 254                        return export_list[i].export;
 255        }
 256        return export_unknown;
 257}
 258
 259static const char *sec_name(struct elf_info *elf, int secindex);
 260
 261#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
 262
 263static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
 264{
 265        const char *secname = sec_name(elf, sec);
 266
 267        if (strstarts(secname, "___ksymtab+"))
 268                return export_plain;
 269        else if (strstarts(secname, "___ksymtab_unused+"))
 270                return export_unused;
 271        else if (strstarts(secname, "___ksymtab_gpl+"))
 272                return export_gpl;
 273        else if (strstarts(secname, "___ksymtab_unused_gpl+"))
 274                return export_unused_gpl;
 275        else if (strstarts(secname, "___ksymtab_gpl_future+"))
 276                return export_gpl_future;
 277        else
 278                return export_unknown;
 279}
 280
 281static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
 282{
 283        if (sec == elf->export_sec)
 284                return export_plain;
 285        else if (sec == elf->export_unused_sec)
 286                return export_unused;
 287        else if (sec == elf->export_gpl_sec)
 288                return export_gpl;
 289        else if (sec == elf->export_unused_gpl_sec)
 290                return export_unused_gpl;
 291        else if (sec == elf->export_gpl_future_sec)
 292                return export_gpl_future;
 293        else
 294                return export_unknown;
 295}
 296
 297/**
 298 * Add an exported symbol - it may have already been added without a
 299 * CRC, in this case just update the CRC
 300 **/
 301static struct symbol *sym_add_exported(const char *name, struct module *mod,
 302                                       enum export export)
 303{
 304        struct symbol *s = find_symbol(name);
 305
 306        if (!s) {
 307                s = new_symbol(name, mod, export);
 308        } else {
 309                if (!s->preloaded) {
 310                        warn("%s: '%s' exported twice. Previous export "
 311                             "was in %s%s\n", mod->name, name,
 312                             s->module->name,
 313                             is_vmlinux(s->module->name) ?"":".ko");
 314                } else {
 315                        /* In case Modules.symvers was out of date */
 316                        s->module = mod;
 317                }
 318        }
 319        s->preloaded = 0;
 320        s->vmlinux   = is_vmlinux(mod->name);
 321        s->kernel    = 0;
 322        s->export    = export;
 323        return s;
 324}
 325
 326static void sym_update_crc(const char *name, struct module *mod,
 327                           unsigned int crc, enum export export)
 328{
 329        struct symbol *s = find_symbol(name);
 330
 331        if (!s)
 332                s = new_symbol(name, mod, export);
 333        s->crc = crc;
 334        s->crc_valid = 1;
 335}
 336
 337void *grab_file(const char *filename, unsigned long *size)
 338{
 339        struct stat st;
 340        void *map = MAP_FAILED;
 341        int fd;
 342
 343        fd = open(filename, O_RDONLY);
 344        if (fd < 0)
 345                return NULL;
 346        if (fstat(fd, &st))
 347                goto failed;
 348
 349        *size = st.st_size;
 350        map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
 351
 352failed:
 353        close(fd);
 354        if (map == MAP_FAILED)
 355                return NULL;
 356        return map;
 357}
 358
 359/**
 360  * Return a copy of the next line in a mmap'ed file.
 361  * spaces in the beginning of the line is trimmed away.
 362  * Return a pointer to a static buffer.
 363  **/
 364char *get_next_line(unsigned long *pos, void *file, unsigned long size)
 365{
 366        static char line[4096];
 367        int skip = 1;
 368        size_t len = 0;
 369        signed char *p = (signed char *)file + *pos;
 370        char *s = line;
 371
 372        for (; *pos < size ; (*pos)++) {
 373                if (skip && isspace(*p)) {
 374                        p++;
 375                        continue;
 376                }
 377                skip = 0;
 378                if (*p != '\n' && (*pos < size)) {
 379                        len++;
 380                        *s++ = *p++;
 381                        if (len > 4095)
 382                                break; /* Too long, stop */
 383                } else {
 384                        /* End of string */
 385                        *s = '\0';
 386                        return line;
 387                }
 388        }
 389        /* End of buffer */
 390        return NULL;
 391}
 392
 393void release_file(void *file, unsigned long size)
 394{
 395        munmap(file, size);
 396}
 397
 398static int parse_elf(struct elf_info *info, const char *filename)
 399{
 400        unsigned int i;
 401        Elf_Ehdr *hdr;
 402        Elf_Shdr *sechdrs;
 403        Elf_Sym  *sym;
 404        const char *secstrings;
 405        unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
 406
 407        hdr = grab_file(filename, &info->size);
 408        if (!hdr) {
 409                perror(filename);
 410                exit(1);
 411        }
 412        info->hdr = hdr;
 413        if (info->size < sizeof(*hdr)) {
 414                /* file too small, assume this is an empty .o file */
 415                return 0;
 416        }
 417        /* Is this a valid ELF file? */
 418        if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
 419            (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
 420            (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
 421            (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
 422                /* Not an ELF file - silently ignore it */
 423                return 0;
 424        }
 425        /* Fix endianness in ELF header */
 426        hdr->e_type      = TO_NATIVE(hdr->e_type);
 427        hdr->e_machine   = TO_NATIVE(hdr->e_machine);
 428        hdr->e_version   = TO_NATIVE(hdr->e_version);
 429        hdr->e_entry     = TO_NATIVE(hdr->e_entry);
 430        hdr->e_phoff     = TO_NATIVE(hdr->e_phoff);
 431        hdr->e_shoff     = TO_NATIVE(hdr->e_shoff);
 432        hdr->e_flags     = TO_NATIVE(hdr->e_flags);
 433        hdr->e_ehsize    = TO_NATIVE(hdr->e_ehsize);
 434        hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
 435        hdr->e_phnum     = TO_NATIVE(hdr->e_phnum);
 436        hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
 437        hdr->e_shnum     = TO_NATIVE(hdr->e_shnum);
 438        hdr->e_shstrndx  = TO_NATIVE(hdr->e_shstrndx);
 439        sechdrs = (void *)hdr + hdr->e_shoff;
 440        info->sechdrs = sechdrs;
 441
 442        /* Check if file offset is correct */
 443        if (hdr->e_shoff > info->size) {
 444                fatal("section header offset=%lu in file '%s' is bigger than "
 445                      "filesize=%lu\n", (unsigned long)hdr->e_shoff,
 446                      filename, info->size);
 447                return 0;
 448        }
 449
 450        if (hdr->e_shnum == SHN_UNDEF) {
 451                /*
 452                 * There are more than 64k sections,
 453                 * read count from .sh_size.
 454                 */
 455                info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
 456        }
 457        else {
 458                info->num_sections = hdr->e_shnum;
 459        }
 460        if (hdr->e_shstrndx == SHN_XINDEX) {
 461                info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
 462        }
 463        else {
 464                info->secindex_strings = hdr->e_shstrndx;
 465        }
 466
 467        /* Fix endianness in section headers */
 468        for (i = 0; i < info->num_sections; i++) {
 469                sechdrs[i].sh_name      = TO_NATIVE(sechdrs[i].sh_name);
 470                sechdrs[i].sh_type      = TO_NATIVE(sechdrs[i].sh_type);
 471                sechdrs[i].sh_flags     = TO_NATIVE(sechdrs[i].sh_flags);
 472                sechdrs[i].sh_addr      = TO_NATIVE(sechdrs[i].sh_addr);
 473                sechdrs[i].sh_offset    = TO_NATIVE(sechdrs[i].sh_offset);
 474                sechdrs[i].sh_size      = TO_NATIVE(sechdrs[i].sh_size);
 475                sechdrs[i].sh_link      = TO_NATIVE(sechdrs[i].sh_link);
 476                sechdrs[i].sh_info      = TO_NATIVE(sechdrs[i].sh_info);
 477                sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
 478                sechdrs[i].sh_entsize   = TO_NATIVE(sechdrs[i].sh_entsize);
 479        }
 480        /* Find symbol table. */
 481        secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
 482        for (i = 1; i < info->num_sections; i++) {
 483                const char *secname;
 484                int nobits = sechdrs[i].sh_type == SHT_NOBITS;
 485
 486                if (!nobits && sechdrs[i].sh_offset > info->size) {
 487                        fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
 488                              "sizeof(*hrd)=%zu\n", filename,
 489                              (unsigned long)sechdrs[i].sh_offset,
 490                              sizeof(*hdr));
 491                        return 0;
 492                }
 493                secname = secstrings + sechdrs[i].sh_name;
 494                if (strcmp(secname, ".modinfo") == 0) {
 495                        if (nobits)
 496                                fatal("%s has NOBITS .modinfo\n", filename);
 497                        info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
 498                        info->modinfo_len = sechdrs[i].sh_size;
 499                } else if (strcmp(secname, "__ksymtab") == 0)
 500                        info->export_sec = i;
 501                else if (strcmp(secname, "__ksymtab_unused") == 0)
 502                        info->export_unused_sec = i;
 503                else if (strcmp(secname, "__ksymtab_gpl") == 0)
 504                        info->export_gpl_sec = i;
 505                else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
 506                        info->export_unused_gpl_sec = i;
 507                else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
 508                        info->export_gpl_future_sec = i;
 509
 510                if (sechdrs[i].sh_type == SHT_SYMTAB) {
 511                        unsigned int sh_link_idx;
 512                        symtab_idx = i;
 513                        info->symtab_start = (void *)hdr +
 514                            sechdrs[i].sh_offset;
 515                        info->symtab_stop  = (void *)hdr +
 516                            sechdrs[i].sh_offset + sechdrs[i].sh_size;
 517                        sh_link_idx = sechdrs[i].sh_link;
 518                        info->strtab       = (void *)hdr +
 519                            sechdrs[sh_link_idx].sh_offset;
 520                }
 521
 522                /* 32bit section no. table? ("more than 64k sections") */
 523                if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
 524                        symtab_shndx_idx = i;
 525                        info->symtab_shndx_start = (void *)hdr +
 526                            sechdrs[i].sh_offset;
 527                        info->symtab_shndx_stop  = (void *)hdr +
 528                            sechdrs[i].sh_offset + sechdrs[i].sh_size;
 529                }
 530        }
 531        if (!info->symtab_start)
 532                fatal("%s has no symtab?\n", filename);
 533
 534        /* Fix endianness in symbols */
 535        for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
 536                sym->st_shndx = TO_NATIVE(sym->st_shndx);
 537                sym->st_name  = TO_NATIVE(sym->st_name);
 538                sym->st_value = TO_NATIVE(sym->st_value);
 539                sym->st_size  = TO_NATIVE(sym->st_size);
 540        }
 541
 542        if (symtab_shndx_idx != ~0U) {
 543                Elf32_Word *p;
 544                if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
 545                        fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
 546                              filename, sechdrs[symtab_shndx_idx].sh_link,
 547                              symtab_idx);
 548                /* Fix endianness */
 549                for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
 550                     p++)
 551                        *p = TO_NATIVE(*p);
 552        }
 553
 554        return 1;
 555}
 556
 557static void parse_elf_finish(struct elf_info *info)
 558{
 559        release_file(info->hdr, info->size);
 560}
 561
 562static int ignore_undef_symbol(struct elf_info *info, const char *symname)
 563{
 564        /* ignore __this_module, it will be resolved shortly */
 565        if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0)
 566                return 1;
 567        /* ignore global offset table */
 568        if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
 569                return 1;
 570        if (info->hdr->e_machine == EM_PPC)
 571                /* Special register function linked on all modules during final link of .ko */
 572                if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
 573                    strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
 574                    strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
 575                    strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0)
 576                        return 1;
 577        if (info->hdr->e_machine == EM_PPC64)
 578                /* Special register function linked on all modules during final link of .ko */
 579                if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
 580                    strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0)
 581                        return 1;
 582        /* Do not ignore this symbol */
 583        return 0;
 584}
 585
 586#define CRC_PFX     MODULE_SYMBOL_PREFIX "__crc_"
 587#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
 588
 589static void handle_modversions(struct module *mod, struct elf_info *info,
 590                               Elf_Sym *sym, const char *symname)
 591{
 592        unsigned int crc;
 593        enum export export;
 594
 595        if ((!is_vmlinux(mod->name) || mod->is_dot_o) &&
 596            strncmp(symname, "__ksymtab", 9) == 0)
 597                export = export_from_secname(info, get_secindex(info, sym));
 598        else
 599                export = export_from_sec(info, get_secindex(info, sym));
 600
 601        switch (sym->st_shndx) {
 602        case SHN_COMMON:
 603                warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
 604                break;
 605        case SHN_ABS:
 606                /* CRC'd symbol */
 607                if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
 608                        crc = (unsigned int) sym->st_value;
 609                        sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
 610                                        export);
 611                }
 612                break;
 613        case SHN_UNDEF:
 614                /* undefined symbol */
 615                if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
 616                    ELF_ST_BIND(sym->st_info) != STB_WEAK)
 617                        break;
 618                if (ignore_undef_symbol(info, symname))
 619                        break;
 620/* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
 621#if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
 622/* add compatibility with older glibc */
 623#ifndef STT_SPARC_REGISTER
 624#define STT_SPARC_REGISTER STT_REGISTER
 625#endif
 626                if (info->hdr->e_machine == EM_SPARC ||
 627                    info->hdr->e_machine == EM_SPARCV9) {
 628                        /* Ignore register directives. */
 629                        if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
 630                                break;
 631                        if (symname[0] == '.') {
 632                                char *munged = strdup(symname);
 633                                munged[0] = '_';
 634                                munged[1] = toupper(munged[1]);
 635                                symname = munged;
 636                        }
 637                }
 638#endif
 639
 640                if (memcmp(symname, MODULE_SYMBOL_PREFIX,
 641                           strlen(MODULE_SYMBOL_PREFIX)) == 0) {
 642                        mod->unres =
 643                          alloc_symbol(symname +
 644                                       strlen(MODULE_SYMBOL_PREFIX),
 645                                       ELF_ST_BIND(sym->st_info) == STB_WEAK,
 646                                       mod->unres);
 647                }
 648                break;
 649        default:
 650                /* All exported symbols */
 651                if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
 652                        sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
 653                                        export);
 654                }
 655                if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
 656                        mod->has_init = 1;
 657                if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0)
 658                        mod->has_cleanup = 1;
 659                break;
 660        }
 661}
 662
 663/**
 664 * Parse tag=value strings from .modinfo section
 665 **/
 666static char *next_string(char *string, unsigned long *secsize)
 667{
 668        /* Skip non-zero chars */
 669        while (string[0]) {
 670                string++;
 671                if ((*secsize)-- <= 1)
 672                        return NULL;
 673        }
 674
 675        /* Skip any zero padding. */
 676        while (!string[0]) {
 677                string++;
 678                if ((*secsize)-- <= 1)
 679                        return NULL;
 680        }
 681        return string;
 682}
 683
 684static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
 685                              const char *tag, char *info)
 686{
 687        char *p;
 688        unsigned int taglen = strlen(tag);
 689        unsigned long size = modinfo_len;
 690
 691        if (info) {
 692                size -= info - (char *)modinfo;
 693                modinfo = next_string(info, &size);
 694        }
 695
 696        for (p = modinfo; p; p = next_string(p, &size)) {
 697                if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
 698                        return p + taglen + 1;
 699        }
 700        return NULL;
 701}
 702
 703static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
 704                         const char *tag)
 705
 706{
 707        return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
 708}
 709
 710/**
 711 * Test if string s ends in string sub
 712 * return 0 if match
 713 **/
 714static int strrcmp(const char *s, const char *sub)
 715{
 716        int slen, sublen;
 717
 718        if (!s || !sub)
 719                return 1;
 720
 721        slen = strlen(s);
 722        sublen = strlen(sub);
 723
 724        if ((slen == 0) || (sublen == 0))
 725                return 1;
 726
 727        if (sublen > slen)
 728                return 1;
 729
 730        return memcmp(s + slen - sublen, sub, sublen);
 731}
 732
 733static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
 734{
 735        if (sym)
 736                return elf->strtab + sym->st_name;
 737        else
 738                return "(unknown)";
 739}
 740
 741static const char *sec_name(struct elf_info *elf, int secindex)
 742{
 743        Elf_Shdr *sechdrs = elf->sechdrs;
 744        return (void *)elf->hdr +
 745                elf->sechdrs[elf->secindex_strings].sh_offset +
 746                sechdrs[secindex].sh_name;
 747}
 748
 749static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
 750{
 751        return (void *)elf->hdr +
 752                elf->sechdrs[elf->secindex_strings].sh_offset +
 753                sechdr->sh_name;
 754}
 755
 756/* if sym is empty or point to a string
 757 * like ".[0-9]+" then return 1.
 758 * This is the optional prefix added by ld to some sections
 759 */
 760static int number_prefix(const char *sym)
 761{
 762        if (*sym++ == '\0')
 763                return 1;
 764        if (*sym != '.')
 765                return 0;
 766        do {
 767                char c = *sym++;
 768                if (c < '0' || c > '9')
 769                        return 0;
 770        } while (*sym);
 771        return 1;
 772}
 773
 774/* The pattern is an array of simple patterns.
 775 * "foo" will match an exact string equal to "foo"
 776 * "*foo" will match a string that ends with "foo"
 777 * "foo*" will match a string that begins with "foo"
 778 * "foo$" will match a string equal to "foo" or "foo.1"
 779 *   where the '1' can be any number including several digits.
 780 *   The $ syntax is for sections where ld append a dot number
 781 *   to make section name unique.
 782 */
 783static int match(const char *sym, const char * const pat[])
 784{
 785        const char *p;
 786        while (*pat) {
 787                p = *pat++;
 788                const char *endp = p + strlen(p) - 1;
 789
 790                /* "*foo" */
 791                if (*p == '*') {
 792                        if (strrcmp(sym, p + 1) == 0)
 793                                return 1;
 794                }
 795                /* "foo*" */
 796                else if (*endp == '*') {
 797                        if (strncmp(sym, p, strlen(p) - 1) == 0)
 798                                return 1;
 799                }
 800                /* "foo$" */
 801                else if (*endp == '$') {
 802                        if (strncmp(sym, p, strlen(p) - 1) == 0) {
 803                                if (number_prefix(sym + strlen(p) - 1))
 804                                        return 1;
 805                        }
 806                }
 807                /* no wildcards */
 808                else {
 809                        if (strcmp(p, sym) == 0)
 810                                return 1;
 811                }
 812        }
 813        /* no match */
 814        return 0;
 815}
 816
 817/* sections that we do not want to do full section mismatch check on */
 818static const char *section_white_list[] =
 819{
 820        ".comment*",
 821        ".debug*",
 822        ".zdebug*",             /* Compressed debug sections. */
 823        ".GCC-command-line",    /* mn10300 */
 824        ".mdebug*",        /* alpha, score, mips etc. */
 825        ".pdr",            /* alpha, score, mips etc. */
 826        ".stab*",
 827        ".note*",
 828        ".got*",
 829        ".toc*",
 830        NULL
 831};
 832
 833/*
 834 * This is used to find sections missing the SHF_ALLOC flag.
 835 * The cause of this is often a section specified in assembler
 836 * without "ax" / "aw".
 837 */
 838static void check_section(const char *modname, struct elf_info *elf,
 839                          Elf_Shdr *sechdr)
 840{
 841        const char *sec = sech_name(elf, sechdr);
 842
 843        if (sechdr->sh_type == SHT_PROGBITS &&
 844            !(sechdr->sh_flags & SHF_ALLOC) &&
 845            !match(sec, section_white_list)) {
 846                warn("%s (%s): unexpected non-allocatable section.\n"
 847                     "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
 848                     "Note that for example <linux/init.h> contains\n"
 849                     "section definitions for use in .S files.\n\n",
 850                     modname, sec);
 851        }
 852}
 853
 854
 855
 856#define ALL_INIT_DATA_SECTIONS \
 857        ".init.setup$", ".init.rodata$", \
 858        ".devinit.rodata$", ".cpuinit.rodata$", ".meminit.rodata$", \
 859        ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$"
 860#define ALL_EXIT_DATA_SECTIONS \
 861        ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$"
 862
 863#define ALL_INIT_TEXT_SECTIONS \
 864        ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$"
 865#define ALL_EXIT_TEXT_SECTIONS \
 866        ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$"
 867
 868#define ALL_PCI_INIT_SECTIONS   \
 869        ".pci_fixup_early$", ".pci_fixup_header$", ".pci_fixup_final$", \
 870        ".pci_fixup_enable$", ".pci_fixup_resume$", \
 871        ".pci_fixup_resume_early$", ".pci_fixup_suspend$"
 872
 873#define ALL_XXXINIT_SECTIONS DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, \
 874        MEM_INIT_SECTIONS
 875#define ALL_XXXEXIT_SECTIONS DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, \
 876        MEM_EXIT_SECTIONS
 877
 878#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
 879#define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
 880
 881#define DATA_SECTIONS ".data$", ".data.rel$"
 882#define TEXT_SECTIONS ".text$"
 883
 884#define INIT_SECTIONS      ".init.*"
 885#define DEV_INIT_SECTIONS  ".devinit.*"
 886#define CPU_INIT_SECTIONS  ".cpuinit.*"
 887#define MEM_INIT_SECTIONS  ".meminit.*"
 888
 889#define EXIT_SECTIONS      ".exit.*"
 890#define DEV_EXIT_SECTIONS  ".devexit.*"
 891#define CPU_EXIT_SECTIONS  ".cpuexit.*"
 892#define MEM_EXIT_SECTIONS  ".memexit.*"
 893
 894/* init data sections */
 895static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL };
 896
 897/* all init sections */
 898static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL };
 899
 900/* All init and exit sections (code + data) */
 901static const char *init_exit_sections[] =
 902        {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
 903
 904/* data section */
 905static 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
 919static const char *head_sections[] = { ".head.text*", NULL };
 920static const char *linker_symbols[] =
 921        { "__init_begin", "_sinittext", "_einittext", NULL };
 922
 923enum 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
 935struct sectioncheck {
 936        const char *fromsec[20];
 937        const char *tosec[20];
 938        enum mismatch mismatch;
 939        const char *symbol_white_list[20];
 940};
 941
 942const 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 devinit/cpuinit/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 cpuinit code/data from meminit code/data */
 987{
 988        .fromsec = { MEM_INIT_SECTIONS, NULL },
 989        .tosec   = { CPU_INIT_SECTIONS, NULL },
 990        .mismatch = XXXINIT_TO_SOME_INIT,
 991        .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
 992},
 993/* Do not reference meminit code/data from cpuinit code/data */
 994{
 995        .fromsec = { CPU_INIT_SECTIONS, NULL },
 996        .tosec   = { MEM_INIT_SECTIONS, NULL },
 997        .mismatch = XXXINIT_TO_SOME_INIT,
 998        .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
 999},
1000/* Do not reference exit code/data from devexit/cpuexit/memexit code/data */
1001{
1002        .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
1003        .tosec   = { EXIT_SECTIONS, NULL },
1004        .mismatch = XXXEXIT_TO_SOME_EXIT,
1005        .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1006},
1007/* Do not reference cpuexit code/data from memexit code/data */
1008{
1009        .fromsec = { MEM_EXIT_SECTIONS, NULL },
1010        .tosec   = { CPU_EXIT_SECTIONS, NULL },
1011        .mismatch = XXXEXIT_TO_SOME_EXIT,
1012        .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1013},
1014/* Do not reference memexit code/data from cpuexit code/data */
1015{
1016        .fromsec = { CPU_EXIT_SECTIONS, NULL },
1017        .tosec   = { MEM_EXIT_SECTIONS, NULL },
1018        .mismatch = XXXEXIT_TO_SOME_EXIT,
1019        .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1020},
1021/* Do not use exit code/data from init code */
1022{
1023        .fromsec = { ALL_INIT_SECTIONS, NULL },
1024        .tosec   = { ALL_EXIT_SECTIONS, NULL },
1025        .mismatch = ANY_INIT_TO_ANY_EXIT,
1026        .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1027},
1028/* Do not use init code/data from exit code */
1029{
1030        .fromsec = { ALL_EXIT_SECTIONS, NULL },
1031        .tosec   = { ALL_INIT_SECTIONS, NULL },
1032        .mismatch = ANY_EXIT_TO_ANY_INIT,
1033        .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1034},
1035{
1036        .fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
1037        .tosec   = { INIT_SECTIONS, NULL },
1038        .mismatch = ANY_INIT_TO_ANY_EXIT,
1039        .symbol_white_list = { NULL },
1040},
1041/* Do not export init/exit functions or data */
1042{
1043        .fromsec = { "__ksymtab*", NULL },
1044        .tosec   = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
1045        .mismatch = EXPORT_TO_INIT_EXIT,
1046        .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1047}
1048};
1049
1050static const struct sectioncheck *section_mismatch(
1051                const char *fromsec, const char *tosec)
1052{
1053        int i;
1054        int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
1055        const struct sectioncheck *check = &sectioncheck[0];
1056
1057        for (i = 0; i < elems; i++) {
1058                if (match(fromsec, check->fromsec) &&
1059                    match(tosec, check->tosec))
1060                        return check;
1061                check++;
1062        }
1063        return NULL;
1064}
1065
1066/**
1067 * Whitelist to allow certain references to pass with no warning.
1068 *
1069 * Pattern 1:
1070 *   If a module parameter is declared __initdata and permissions=0
1071 *   then this is legal despite the warning generated.
1072 *   We cannot see value of permissions here, so just ignore
1073 *   this pattern.
1074 *   The pattern is identified by:
1075 *   tosec   = .init.data
1076 *   fromsec = .data*
1077 *   atsym   =__param*
1078 *
1079 * Pattern 1a:
1080 *   module_param_call() ops can refer to __init set function if permissions=0
1081 *   The pattern is identified by:
1082 *   tosec   = .init.text
1083 *   fromsec = .data*
1084 *   atsym   = __param_ops_*
1085 *
1086 * Pattern 2:
1087 *   Many drivers utilise a *driver container with references to
1088 *   add, remove, probe functions etc.
1089 *   These functions may often be marked __devinit and we do not want to
1090 *   warn here.
1091 *   the pattern is identified by:
1092 *   tosec   = init or exit section
1093 *   fromsec = data section
1094 *   atsym = *driver, *_template, *_sht, *_ops, *_probe,
1095 *           *probe_one, *_console, *_timer
1096 *
1097 * Pattern 3:
1098 *   Whitelist all references from .head.text to any init section
1099 *
1100 * Pattern 4:
1101 *   Some symbols belong to init section but still it is ok to reference
1102 *   these from non-init sections as these symbols don't have any memory
1103 *   allocated for them and symbol address and value are same. So even
1104 *   if init section is freed, its ok to reference those symbols.
1105 *   For ex. symbols marking the init section boundaries.
1106 *   This pattern is identified by
1107 *   refsymname = __init_begin, _sinittext, _einittext
1108 *
1109 **/
1110static int secref_whitelist(const struct sectioncheck *mismatch,
1111                            const char *fromsec, const char *fromsym,
1112                            const char *tosec, const char *tosym)
1113{
1114        /* Check for pattern 1 */
1115        if (match(tosec, init_data_sections) &&
1116            match(fromsec, data_sections) &&
1117            (strncmp(fromsym, "__param", strlen("__param")) == 0))
1118                return 0;
1119
1120        /* Check for pattern 1a */
1121        if (strcmp(tosec, ".init.text") == 0 &&
1122            match(fromsec, data_sections) &&
1123            (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0))
1124                return 0;
1125
1126        /* Check for pattern 2 */
1127        if (match(tosec, init_exit_sections) &&
1128            match(fromsec, data_sections) &&
1129            match(fromsym, mismatch->symbol_white_list))
1130                return 0;
1131
1132        /* Check for pattern 3 */
1133        if (match(fromsec, head_sections) &&
1134            match(tosec, init_sections))
1135                return 0;
1136
1137        /* Check for pattern 4 */
1138        if (match(tosym, linker_symbols))
1139                return 0;
1140
1141        return 1;
1142}
1143
1144/**
1145 * Find symbol based on relocation record info.
1146 * In some cases the symbol supplied is a valid symbol so
1147 * return refsym. If st_name != 0 we assume this is a valid symbol.
1148 * In other cases the symbol needs to be looked up in the symbol table
1149 * based on section and address.
1150 *  **/
1151static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
1152                                Elf_Sym *relsym)
1153{
1154        Elf_Sym *sym;
1155        Elf_Sym *near = NULL;
1156        Elf64_Sword distance = 20;
1157        Elf64_Sword d;
1158        unsigned int relsym_secindex;
1159
1160        if (relsym->st_name != 0)
1161                return relsym;
1162
1163        relsym_secindex = get_secindex(elf, relsym);
1164        for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1165                if (get_secindex(elf, sym) != relsym_secindex)
1166                        continue;
1167                if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
1168                        continue;
1169                if (sym->st_value == addr)
1170                        return sym;
1171                /* Find a symbol nearby - addr are maybe negative */
1172                d = sym->st_value - addr;
1173                if (d < 0)
1174                        d = addr - sym->st_value;
1175                if (d < distance) {
1176                        distance = d;
1177                        near = sym;
1178                }
1179        }
1180        /* We need a close match */
1181        if (distance < 20)
1182                return near;
1183        else
1184                return NULL;
1185}
1186
1187static inline int is_arm_mapping_symbol(const char *str)
1188{
1189        return str[0] == '$' && strchr("atd", str[1])
1190               && (str[2] == '\0' || str[2] == '.');
1191}
1192
1193/*
1194 * If there's no name there, ignore it; likewise, ignore it if it's
1195 * one of the magic symbols emitted used by current ARM tools.
1196 *
1197 * Otherwise if find_symbols_between() returns those symbols, they'll
1198 * fail the whitelist tests and cause lots of false alarms ... fixable
1199 * only by merging __exit and __init sections into __text, bloating
1200 * the kernel (which is especially evil on embedded platforms).
1201 */
1202static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
1203{
1204        const char *name = elf->strtab + sym->st_name;
1205
1206        if (!name || !strlen(name))
1207                return 0;
1208        return !is_arm_mapping_symbol(name);
1209}
1210
1211/*
1212 * Find symbols before or equal addr and after addr - in the section sec.
1213 * If we find two symbols with equal offset prefer one with a valid name.
1214 * The ELF format may have a better way to detect what type of symbol
1215 * it is, but this works for now.
1216 **/
1217static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
1218                                 const char *sec)
1219{
1220        Elf_Sym *sym;
1221        Elf_Sym *near = NULL;
1222        Elf_Addr distance = ~0;
1223
1224        for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1225                const char *symsec;
1226
1227                if (is_shndx_special(sym->st_shndx))
1228                        continue;
1229                symsec = sec_name(elf, get_secindex(elf, sym));
1230                if (strcmp(symsec, sec) != 0)
1231                        continue;
1232                if (!is_valid_name(elf, sym))
1233                        continue;
1234                if (sym->st_value <= addr) {
1235                        if ((addr - sym->st_value) < distance) {
1236                                distance = addr - sym->st_value;
1237                                near = sym;
1238                        } else if ((addr - sym->st_value) == distance) {
1239                                near = sym;
1240                        }
1241                }
1242        }
1243        return near;
1244}
1245
1246/*
1247 * Convert a section name to the function/data attribute
1248 * .init.text => __init
1249 * .cpuinit.data => __cpudata
1250 * .memexitconst => __memconst
1251 * etc.
1252 *
1253 * The memory of returned value has been allocated on a heap. The user of this
1254 * method should free it after usage.
1255*/
1256static char *sec2annotation(const char *s)
1257{
1258        if (match(s, init_exit_sections)) {
1259                char *p = malloc(20);
1260                char *r = p;
1261
1262                *p++ = '_';
1263                *p++ = '_';
1264                if (*s == '.')
1265                        s++;
1266                while (*s && *s != '.')
1267                        *p++ = *s++;
1268                *p = '\0';
1269                if (*s == '.')
1270                        s++;
1271                if (strstr(s, "rodata") != NULL)
1272                        strcat(p, "const ");
1273                else if (strstr(s, "data") != NULL)
1274                        strcat(p, "data ");
1275                else
1276                        strcat(p, " ");
1277                return r;
1278        } else {
1279                return strdup("");
1280        }
1281}
1282
1283static int is_function(Elf_Sym *sym)
1284{
1285        if (sym)
1286                return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
1287        else
1288                return -1;
1289}
1290
1291static void print_section_list(const char * const list[20])
1292{
1293        const char *const *s = list;
1294
1295        while (*s) {
1296                fprintf(stderr, "%s", *s);
1297                s++;
1298                if (*s)
1299                        fprintf(stderr, ", ");
1300        }
1301        fprintf(stderr, "\n");
1302}
1303
1304/*
1305 * Print a warning about a section mismatch.
1306 * Try to find symbols near it so user can find it.
1307 * Check whitelist before warning - it may be a false positive.
1308 */
1309static void report_sec_mismatch(const char *modname,
1310                                const struct sectioncheck *mismatch,
1311                                const char *fromsec,
1312                                unsigned long long fromaddr,
1313                                const char *fromsym,
1314                                int from_is_func,
1315                                const char *tosec, const char *tosym,
1316                                int to_is_func)
1317{
1318        const char *from, *from_p;
1319        const char *to, *to_p;
1320        char *prl_from;
1321        char *prl_to;
1322
1323        switch (from_is_func) {
1324        case 0: from = "variable"; from_p = "";   break;
1325        case 1: from = "function"; from_p = "()"; break;
1326        default: from = "(unknown reference)"; from_p = ""; break;
1327        }
1328        switch (to_is_func) {
1329        case 0: to = "variable"; to_p = "";   break;
1330        case 1: to = "function"; to_p = "()"; break;
1331        default: to = "(unknown reference)"; to_p = ""; break;
1332        }
1333
1334        sec_mismatch_count++;
1335        if (!sec_mismatch_verbose)
1336                return;
1337
1338        warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1339             "to the %s %s:%s%s\n",
1340             modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
1341             tosym, to_p);
1342
1343        switch (mismatch->mismatch) {
1344        case TEXT_TO_ANY_INIT:
1345                prl_from = sec2annotation(fromsec);
1346                prl_to = sec2annotation(tosec);
1347                fprintf(stderr,
1348                "The function %s%s() references\n"
1349                "the %s %s%s%s.\n"
1350                "This is often because %s lacks a %s\n"
1351                "annotation or the annotation of %s is wrong.\n",
1352                prl_from, fromsym,
1353                to, prl_to, tosym, to_p,
1354                fromsym, prl_to, tosym);
1355                free(prl_from);
1356                free(prl_to);
1357                break;
1358        case DATA_TO_ANY_INIT: {
1359                prl_to = sec2annotation(tosec);
1360                fprintf(stderr,
1361                "The variable %s references\n"
1362                "the %s %s%s%s\n"
1363                "If the reference is valid then annotate the\n"
1364                "variable with __init* or __refdata (see linux/init.h) "
1365                "or name the variable:\n",
1366                fromsym, to, prl_to, tosym, to_p);
1367                print_section_list(mismatch->symbol_white_list);
1368                free(prl_to);
1369                break;
1370        }
1371        case TEXT_TO_ANY_EXIT:
1372                prl_to = sec2annotation(tosec);
1373                fprintf(stderr,
1374                "The function %s() references a %s in an exit section.\n"
1375                "Often the %s %s%s has valid usage outside the exit section\n"
1376                "and the fix is to remove the %sannotation of %s.\n",
1377                fromsym, to, to, tosym, to_p, prl_to, tosym);
1378                free(prl_to);
1379                break;
1380        case DATA_TO_ANY_EXIT: {
1381                prl_to = sec2annotation(tosec);
1382                fprintf(stderr,
1383                "The variable %s references\n"
1384                "the %s %s%s%s\n"
1385                "If the reference is valid then annotate the\n"
1386                "variable with __exit* (see linux/init.h) or "
1387                "name the variable:\n",
1388                fromsym, to, prl_to, tosym, to_p);
1389                print_section_list(mismatch->symbol_white_list);
1390                free(prl_to);
1391                break;
1392        }
1393        case XXXINIT_TO_SOME_INIT:
1394        case XXXEXIT_TO_SOME_EXIT:
1395                prl_from = sec2annotation(fromsec);
1396                prl_to = sec2annotation(tosec);
1397                fprintf(stderr,
1398                "The %s %s%s%s references\n"
1399                "a %s %s%s%s.\n"
1400                "If %s is only used by %s then\n"
1401                "annotate %s with a matching annotation.\n",
1402                from, prl_from, fromsym, from_p,
1403                to, prl_to, tosym, to_p,
1404                tosym, fromsym, tosym);
1405                free(prl_from);
1406                free(prl_to);
1407                break;
1408        case ANY_INIT_TO_ANY_EXIT:
1409                prl_from = sec2annotation(fromsec);
1410                prl_to = sec2annotation(tosec);
1411                fprintf(stderr,
1412                "The %s %s%s%s references\n"
1413                "a %s %s%s%s.\n"
1414                "This is often seen when error handling "
1415                "in the init function\n"
1416                "uses functionality in the exit path.\n"
1417                "The fix is often to remove the %sannotation of\n"
1418                "%s%s so it may be used outside an exit section.\n",
1419                from, prl_from, fromsym, from_p,
1420                to, prl_to, tosym, to_p,
1421                prl_to, tosym, to_p);
1422                free(prl_from);
1423                free(prl_to);
1424                break;
1425        case ANY_EXIT_TO_ANY_INIT:
1426                prl_from = sec2annotation(fromsec);
1427                prl_to = sec2annotation(tosec);
1428                fprintf(stderr,
1429                "The %s %s%s%s references\n"
1430                "a %s %s%s%s.\n"
1431                "This is often seen when error handling "
1432                "in the exit function\n"
1433                "uses functionality in the init path.\n"
1434                "The fix is often to remove the %sannotation of\n"
1435                "%s%s so it may be used outside an init section.\n",
1436                from, prl_from, fromsym, from_p,
1437                to, prl_to, tosym, to_p,
1438                prl_to, tosym, to_p);
1439                free(prl_from);
1440                free(prl_to);
1441                break;
1442        case EXPORT_TO_INIT_EXIT:
1443                prl_to = sec2annotation(tosec);
1444                fprintf(stderr,
1445                "The symbol %s is exported and annotated %s\n"
1446                "Fix this by removing the %sannotation of %s "
1447                "or drop the export.\n",
1448                tosym, prl_to, prl_to, tosym);
1449                free(prl_to);
1450                break;
1451        }
1452        fprintf(stderr, "\n");
1453}
1454
1455static void check_section_mismatch(const char *modname, struct elf_info *elf,
1456                                   Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1457{
1458        const char *tosec;
1459        const struct sectioncheck *mismatch;
1460
1461        tosec = sec_name(elf, get_secindex(elf, sym));
1462        mismatch = section_mismatch(fromsec, tosec);
1463        if (mismatch) {
1464                Elf_Sym *to;
1465                Elf_Sym *from;
1466                const char *tosym;
1467                const char *fromsym;
1468
1469                from = find_elf_symbol2(elf, r->r_offset, fromsec);
1470                fromsym = sym_name(elf, from);
1471                to = find_elf_symbol(elf, r->r_addend, sym);
1472                tosym = sym_name(elf, to);
1473
1474                /* check whitelist - we may ignore it */
1475                if (secref_whitelist(mismatch,
1476                                        fromsec, fromsym, tosec, tosym)) {
1477                        report_sec_mismatch(modname, mismatch,
1478                           fromsec, r->r_offset, fromsym,
1479                           is_function(from), tosec, tosym,
1480                           is_function(to));
1481                }
1482        }
1483}
1484
1485static unsigned int *reloc_location(struct elf_info *elf,
1486                                    Elf_Shdr *sechdr, Elf_Rela *r)
1487{
1488        Elf_Shdr *sechdrs = elf->sechdrs;
1489        int section = sechdr->sh_info;
1490
1491        return (void *)elf->hdr + sechdrs[section].sh_offset +
1492                r->r_offset;
1493}
1494
1495static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1496{
1497        unsigned int r_typ = ELF_R_TYPE(r->r_info);
1498        unsigned int *location = reloc_location(elf, sechdr, r);
1499
1500        switch (r_typ) {
1501        case R_386_32:
1502                r->r_addend = TO_NATIVE(*location);
1503                break;
1504        case R_386_PC32:
1505                r->r_addend = TO_NATIVE(*location) + 4;
1506                /* For CONFIG_RELOCATABLE=y */
1507                if (elf->hdr->e_type == ET_EXEC)
1508                        r->r_addend += r->r_offset;
1509                break;
1510        }
1511        return 0;
1512}
1513
1514#ifndef R_ARM_CALL
1515#define R_ARM_CALL      28
1516#endif
1517#ifndef R_ARM_JUMP24
1518#define R_ARM_JUMP24    29
1519#endif
1520
1521static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1522{
1523        unsigned int r_typ = ELF_R_TYPE(r->r_info);
1524
1525        switch (r_typ) {
1526        case R_ARM_ABS32:
1527                /* From ARM ABI: (S + A) | T */
1528                r->r_addend = (int)(long)
1529                              (elf->symtab_start + ELF_R_SYM(r->r_info));
1530                break;
1531        case R_ARM_PC24:
1532        case R_ARM_CALL:
1533        case R_ARM_JUMP24:
1534                /* From ARM ABI: ((S + A) | T) - P */
1535                r->r_addend = (int)(long)(elf->hdr +
1536                              sechdr->sh_offset +
1537                              (r->r_offset - sechdr->sh_addr));
1538                break;
1539        default:
1540                return 1;
1541        }
1542        return 0;
1543}
1544
1545static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1546{
1547        unsigned int r_typ = ELF_R_TYPE(r->r_info);
1548        unsigned int *location = reloc_location(elf, sechdr, r);
1549        unsigned int inst;
1550
1551        if (r_typ == R_MIPS_HI16)
1552                return 1;       /* skip this */
1553        inst = TO_NATIVE(*location);
1554        switch (r_typ) {
1555        case R_MIPS_LO16:
1556                r->r_addend = inst & 0xffff;
1557                break;
1558        case R_MIPS_26:
1559                r->r_addend = (inst & 0x03ffffff) << 2;
1560                break;
1561        case R_MIPS_32:
1562                r->r_addend = inst;
1563                break;
1564        }
1565        return 0;
1566}
1567
1568static void section_rela(const char *modname, struct elf_info *elf,
1569                         Elf_Shdr *sechdr)
1570{
1571        Elf_Sym  *sym;
1572        Elf_Rela *rela;
1573        Elf_Rela r;
1574        unsigned int r_sym;
1575        const char *fromsec;
1576
1577        Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
1578        Elf_Rela *stop  = (void *)start + sechdr->sh_size;
1579
1580        fromsec = sech_name(elf, sechdr);
1581        fromsec += strlen(".rela");
1582        /* if from section (name) is know good then skip it */
1583        if (match(fromsec, section_white_list))
1584                return;
1585
1586        for (rela = start; rela < stop; rela++) {
1587                r.r_offset = TO_NATIVE(rela->r_offset);
1588#if KERNEL_ELFCLASS == ELFCLASS64
1589                if (elf->hdr->e_machine == EM_MIPS) {
1590                        unsigned int r_typ;
1591                        r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1592                        r_sym = TO_NATIVE(r_sym);
1593                        r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1594                        r.r_info = ELF64_R_INFO(r_sym, r_typ);
1595                } else {
1596                        r.r_info = TO_NATIVE(rela->r_info);
1597                        r_sym = ELF_R_SYM(r.r_info);
1598                }
1599#else
1600                r.r_info = TO_NATIVE(rela->r_info);
1601                r_sym = ELF_R_SYM(r.r_info);
1602#endif
1603                r.r_addend = TO_NATIVE(rela->r_addend);
1604                sym = elf->symtab_start + r_sym;
1605                /* Skip special sections */
1606                if (is_shndx_special(sym->st_shndx))
1607                        continue;
1608                check_section_mismatch(modname, elf, &r, sym, fromsec);
1609        }
1610}
1611
1612static void section_rel(const char *modname, struct elf_info *elf,
1613                        Elf_Shdr *sechdr)
1614{
1615        Elf_Sym *sym;
1616        Elf_Rel *rel;
1617        Elf_Rela r;
1618        unsigned int r_sym;
1619        const char *fromsec;
1620
1621        Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
1622        Elf_Rel *stop  = (void *)start + sechdr->sh_size;
1623
1624        fromsec = sech_name(elf, sechdr);
1625        fromsec += strlen(".rel");
1626        /* if from section (name) is know good then skip it */
1627        if (match(fromsec, section_white_list))
1628                return;
1629
1630        for (rel = start; rel < stop; rel++) {
1631                r.r_offset = TO_NATIVE(rel->r_offset);
1632#if KERNEL_ELFCLASS == ELFCLASS64
1633                if (elf->hdr->e_machine == EM_MIPS) {
1634                        unsigned int r_typ;
1635                        r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1636                        r_sym = TO_NATIVE(r_sym);
1637                        r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1638                        r.r_info = ELF64_R_INFO(r_sym, r_typ);
1639                } else {
1640                        r.r_info = TO_NATIVE(rel->r_info);
1641                        r_sym = ELF_R_SYM(r.r_info);
1642                }
1643#else
1644                r.r_info = TO_NATIVE(rel->r_info);
1645                r_sym = ELF_R_SYM(r.r_info);
1646#endif
1647                r.r_addend = 0;
1648                switch (elf->hdr->e_machine) {
1649                case EM_386:
1650                        if (addend_386_rel(elf, sechdr, &r))
1651                                continue;
1652                        break;
1653                case EM_ARM:
1654                        if (addend_arm_rel(elf, sechdr, &r))
1655                                continue;
1656                        break;
1657                case EM_MIPS:
1658                        if (addend_mips_rel(elf, sechdr, &r))
1659                                continue;
1660                        break;
1661                }
1662                sym = elf->symtab_start + r_sym;
1663                /* Skip special sections */
1664                if (is_shndx_special(sym->st_shndx))
1665                        continue;
1666                check_section_mismatch(modname, elf, &r, sym, fromsec);
1667        }
1668}
1669
1670/**
1671 * A module includes a number of sections that are discarded
1672 * either when loaded or when used as built-in.
1673 * For loaded modules all functions marked __init and all data
1674 * marked __initdata will be discarded when the module has been initialized.
1675 * Likewise for modules used built-in the sections marked __exit
1676 * are discarded because __exit marked function are supposed to be called
1677 * only when a module is unloaded which never happens for built-in modules.
1678 * The check_sec_ref() function traverses all relocation records
1679 * to find all references to a section that reference a section that will
1680 * be discarded and warns about it.
1681 **/
1682static void check_sec_ref(struct module *mod, const char *modname,
1683                          struct elf_info *elf)
1684{
1685        int i;
1686        Elf_Shdr *sechdrs = elf->sechdrs;
1687
1688        /* Walk through all sections */
1689        for (i = 0; i < elf->num_sections; i++) {
1690                check_section(modname, elf, &elf->sechdrs[i]);
1691                /* We want to process only relocation sections and not .init */
1692                if (sechdrs[i].sh_type == SHT_RELA)
1693                        section_rela(modname, elf, &elf->sechdrs[i]);
1694                else if (sechdrs[i].sh_type == SHT_REL)
1695                        section_rel(modname, elf, &elf->sechdrs[i]);
1696        }
1697}
1698
1699static void read_symbols(char *modname)
1700{
1701        const char *symname;
1702        char *version;
1703        char *license;
1704        struct module *mod;
1705        struct elf_info info = { };
1706        Elf_Sym *sym;
1707
1708        if (!parse_elf(&info, modname))
1709                return;
1710
1711        mod = new_module(modname);
1712
1713        /* When there's no vmlinux, don't print warnings about
1714         * unresolved symbols (since there'll be too many ;) */
1715        if (is_vmlinux(modname)) {
1716                have_vmlinux = 1;
1717                mod->skip = 1;
1718        }
1719
1720        license = get_modinfo(info.modinfo, info.modinfo_len, "license");
1721        if (info.modinfo && !license && !is_vmlinux(modname))
1722                warn("modpost: missing MODULE_LICENSE() in %s\n"
1723                     "see include/linux/module.h for "
1724                     "more information\n", modname);
1725        while (license) {
1726                if (license_is_gpl_compatible(license))
1727                        mod->gpl_compatible = 1;
1728                else {
1729                        mod->gpl_compatible = 0;
1730                        break;
1731                }
1732                license = get_next_modinfo(info.modinfo, info.modinfo_len,
1733                                           "license", license);
1734        }
1735
1736        for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1737                symname = info.strtab + sym->st_name;
1738
1739                handle_modversions(mod, &info, sym, symname);
1740                handle_moddevtable(mod, &info, sym, symname);
1741        }
1742        if (!is_vmlinux(modname) ||
1743             (is_vmlinux(modname) && vmlinux_section_warnings))
1744                check_sec_ref(mod, modname, &info);
1745
1746        version = get_modinfo(info.modinfo, info.modinfo_len, "version");
1747        if (version)
1748                maybe_frob_rcs_version(modname, version, info.modinfo,
1749                                       version - (char *)info.hdr);
1750        if (version || (all_versions && !is_vmlinux(modname)))
1751                get_src_version(modname, mod->srcversion,
1752                                sizeof(mod->srcversion)-1);
1753
1754        parse_elf_finish(&info);
1755
1756        /* Our trick to get versioning for module struct etc. - it's
1757         * never passed as an argument to an exported function, so
1758         * the automatic versioning doesn't pick it up, but it's really
1759         * important anyhow */
1760        if (modversions)
1761                mod->unres = alloc_symbol("module_layout", 0, mod->unres);
1762}
1763
1764#define SZ 500
1765
1766/* We first write the generated file into memory using the
1767 * following helper, then compare to the file on disk and
1768 * only update the later if anything changed */
1769
1770void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1771                                                      const char *fmt, ...)
1772{
1773        char tmp[SZ];
1774        int len;
1775        va_list ap;
1776
1777        va_start(ap, fmt);
1778        len = vsnprintf(tmp, SZ, fmt, ap);
1779        buf_write(buf, tmp, len);
1780        va_end(ap);
1781}
1782
1783void buf_write(struct buffer *buf, const char *s, int len)
1784{
1785        if (buf->size - buf->pos < len) {
1786                buf->size += len + SZ;
1787                buf->p = realloc(buf->p, buf->size);
1788        }
1789        strncpy(buf->p + buf->pos, s, len);
1790        buf->pos += len;
1791}
1792
1793static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
1794{
1795        const char *e = is_vmlinux(m) ?"":".ko";
1796
1797        switch (exp) {
1798        case export_gpl:
1799                fatal("modpost: GPL-incompatible module %s%s "
1800                      "uses GPL-only symbol '%s'\n", m, e, s);
1801                break;
1802        case export_unused_gpl:
1803                fatal("modpost: GPL-incompatible module %s%s "
1804                      "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
1805                break;
1806        case export_gpl_future:
1807                warn("modpost: GPL-incompatible module %s%s "
1808                      "uses future GPL-only symbol '%s'\n", m, e, s);
1809                break;
1810        case export_plain:
1811        case export_unused:
1812        case export_unknown:
1813                /* ignore */
1814                break;
1815        }
1816}
1817
1818static void check_for_unused(enum export exp, const char *m, const char *s)
1819{
1820        const char *e = is_vmlinux(m) ?"":".ko";
1821
1822        switch (exp) {
1823        case export_unused:
1824        case export_unused_gpl:
1825                warn("modpost: module %s%s "
1826                      "uses symbol '%s' marked UNUSED\n", m, e, s);
1827                break;
1828        default:
1829                /* ignore */
1830                break;
1831        }
1832}
1833
1834static void check_exports(struct module *mod)
1835{
1836        struct symbol *s, *exp;
1837
1838        for (s = mod->unres; s; s = s->next) {
1839                const char *basename;
1840                exp = find_symbol(s->name);
1841                if (!exp || exp->module == mod)
1842                        continue;
1843                basename = strrchr(mod->name, '/');
1844                if (basename)
1845                        basename++;
1846                else
1847                        basename = mod->name;
1848                if (!mod->gpl_compatible)
1849                        check_for_gpl_usage(exp->export, basename, exp->name);
1850                check_for_unused(exp->export, basename, exp->name);
1851        }
1852}
1853
1854/**
1855 * Header for the generated file
1856 **/
1857static void add_header(struct buffer *b, struct module *mod)
1858{
1859        buf_printf(b, "#include <linux/module.h>\n");
1860        buf_printf(b, "#include <linux/vermagic.h>\n");
1861        buf_printf(b, "#include <linux/compiler.h>\n");
1862        buf_printf(b, "\n");
1863        buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1864        buf_printf(b, "\n");
1865        buf_printf(b, "struct module __this_module\n");
1866        buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
1867        buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
1868        if (mod->has_init)
1869                buf_printf(b, "\t.init = init_module,\n");
1870        if (mod->has_cleanup)
1871                buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1872                              "\t.exit = cleanup_module,\n"
1873                              "#endif\n");
1874        buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
1875        buf_printf(b, "};\n");
1876}
1877
1878static void add_intree_flag(struct buffer *b, int is_intree)
1879{
1880        if (is_intree)
1881                buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
1882}
1883
1884static void add_staging_flag(struct buffer *b, const char *name)
1885{
1886        static const char *staging_dir = "drivers/staging";
1887
1888        if (strncmp(staging_dir, name, strlen(staging_dir)) == 0)
1889                buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
1890}
1891
1892/**
1893 * Record CRCs for unresolved symbols
1894 **/
1895static int add_versions(struct buffer *b, struct module *mod)
1896{
1897        struct symbol *s, *exp;
1898        int err = 0;
1899
1900        for (s = mod->unres; s; s = s->next) {
1901                exp = find_symbol(s->name);
1902                if (!exp || exp->module == mod) {
1903                        if (have_vmlinux && !s->weak) {
1904                                if (warn_unresolved) {
1905                                        warn("\"%s\" [%s.ko] undefined!\n",
1906                                             s->name, mod->name);
1907                                } else {
1908                                        merror("\"%s\" [%s.ko] undefined!\n",
1909                                                  s->name, mod->name);
1910                                        err = 1;
1911                                }
1912                        }
1913                        continue;
1914                }
1915                s->module = exp->module;
1916                s->crc_valid = exp->crc_valid;
1917                s->crc = exp->crc;
1918        }
1919
1920        if (!modversions)
1921                return err;
1922
1923        buf_printf(b, "\n");
1924        buf_printf(b, "static const struct modversion_info ____versions[]\n");
1925        buf_printf(b, "__used\n");
1926        buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
1927
1928        for (s = mod->unres; s; s = s->next) {
1929                if (!s->module)
1930                        continue;
1931                if (!s->crc_valid) {
1932                        warn("\"%s\" [%s.ko] has no CRC!\n",
1933                                s->name, mod->name);
1934                        continue;
1935                }
1936                buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name);
1937        }
1938
1939        buf_printf(b, "};\n");
1940
1941        return err;
1942}
1943
1944static void add_depends(struct buffer *b, struct module *mod,
1945                        struct module *modules)
1946{
1947        struct symbol *s;
1948        struct module *m;
1949        int first = 1;
1950
1951        for (m = modules; m; m = m->next)
1952                m->seen = is_vmlinux(m->name);
1953
1954        buf_printf(b, "\n");
1955        buf_printf(b, "static const char __module_depends[]\n");
1956        buf_printf(b, "__used\n");
1957        buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
1958        buf_printf(b, "\"depends=");
1959        for (s = mod->unres; s; s = s->next) {
1960                const char *p;
1961                if (!s->module)
1962                        continue;
1963
1964                if (s->module->seen)
1965                        continue;
1966
1967                s->module->seen = 1;
1968                p = strrchr(s->module->name, '/');
1969                if (p)
1970                        p++;
1971                else
1972                        p = s->module->name;
1973                buf_printf(b, "%s%s", first ? "" : ",", p);
1974                first = 0;
1975        }
1976        buf_printf(b, "\";\n");
1977}
1978
1979static void add_srcversion(struct buffer *b, struct module *mod)
1980{
1981        if (mod->srcversion[0]) {
1982                buf_printf(b, "\n");
1983                buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
1984                           mod->srcversion);
1985        }
1986}
1987
1988static void write_if_changed(struct buffer *b, const char *fname)
1989{
1990        char *tmp;
1991        FILE *file;
1992        struct stat st;
1993
1994        file = fopen(fname, "r");
1995        if (!file)
1996                goto write;
1997
1998        if (fstat(fileno(file), &st) < 0)
1999                goto close_write;
2000
2001        if (st.st_size != b->pos)
2002                goto close_write;
2003
2004        tmp = NOFAIL(malloc(b->pos));
2005        if (fread(tmp, 1, b->pos, file) != b->pos)
2006                goto free_write;
2007
2008        if (memcmp(tmp, b->p, b->pos) != 0)
2009                goto free_write;
2010
2011        free(tmp);
2012        fclose(file);
2013        return;
2014
2015 free_write:
2016        free(tmp);
2017 close_write:
2018        fclose(file);
2019 write:
2020        file = fopen(fname, "w");
2021        if (!file) {
2022                perror(fname);
2023                exit(1);
2024        }
2025        if (fwrite(b->p, 1, b->pos, file) != b->pos) {
2026                perror(fname);
2027                exit(1);
2028        }
2029        fclose(file);
2030}
2031
2032/* parse Module.symvers file. line format:
2033 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
2034 **/
2035static void read_dump(const char *fname, unsigned int kernel)
2036{
2037        unsigned long size, pos = 0;
2038        void *file = grab_file(fname, &size);
2039        char *line;
2040
2041        if (!file)
2042                /* No symbol versions, silently ignore */
2043                return;
2044
2045        while ((line = get_next_line(&pos, file, size))) {
2046                char *symname, *modname, *d, *export, *end;
2047                unsigned int crc;
2048                struct module *mod;
2049                struct symbol *s;
2050
2051                if (!(symname = strchr(line, '\t')))
2052                        goto fail;
2053                *symname++ = '\0';
2054                if (!(modname = strchr(symname, '\t')))
2055                        goto fail;
2056                *modname++ = '\0';
2057                if ((export = strchr(modname, '\t')) != NULL)
2058                        *export++ = '\0';
2059                if (export && ((end = strchr(export, '\t')) != NULL))
2060                        *end = '\0';
2061                crc = strtoul(line, &d, 16);
2062                if (*symname == '\0' || *modname == '\0' || *d != '\0')
2063                        goto fail;
2064                mod = find_module(modname);
2065                if (!mod) {
2066                        if (is_vmlinux(modname))
2067                                have_vmlinux = 1;
2068                        mod = new_module(modname);
2069                        mod->skip = 1;
2070                }
2071                s = sym_add_exported(symname, mod, export_no(export));
2072                s->kernel    = kernel;
2073                s->preloaded = 1;
2074                sym_update_crc(symname, mod, crc, export_no(export));
2075        }
2076        return;
2077fail:
2078        fatal("parse error in symbol dump file\n");
2079}
2080
2081/* For normal builds always dump all symbols.
2082 * For external modules only dump symbols
2083 * that are not read from kernel Module.symvers.
2084 **/
2085static int dump_sym(struct symbol *sym)
2086{
2087        if (!external_module)
2088                return 1;
2089        if (sym->vmlinux || sym->kernel)
2090                return 0;
2091        return 1;
2092}
2093
2094static void write_dump(const char *fname)
2095{
2096        struct buffer buf = { };
2097        struct symbol *symbol;
2098        int n;
2099
2100        for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
2101                symbol = symbolhash[n];
2102                while (symbol) {
2103                        if (dump_sym(symbol))
2104                                buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
2105                                        symbol->crc, symbol->name,
2106                                        symbol->module->name,
2107                                        export_str(symbol->export));
2108                        symbol = symbol->next;
2109                }
2110        }
2111        write_if_changed(&buf, fname);
2112}
2113
2114struct ext_sym_list {
2115        struct ext_sym_list *next;
2116        const char *file;
2117};
2118
2119int main(int argc, char **argv)
2120{
2121        struct module *mod;
2122        struct buffer buf = { };
2123        char *kernel_read = NULL, *module_read = NULL;
2124        char *dump_write = NULL;
2125        int opt;
2126        int err;
2127        struct ext_sym_list *extsym_iter;
2128        struct ext_sym_list *extsym_start = NULL;
2129
2130        while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) {
2131                switch (opt) {
2132                case 'i':
2133                        kernel_read = optarg;
2134                        break;
2135                case 'I':
2136                        module_read = optarg;
2137                        external_module = 1;
2138                        break;
2139                case 'c':
2140                        cross_build = 1;
2141                        break;
2142                case 'e':
2143                        external_module = 1;
2144                        extsym_iter =
2145                           NOFAIL(malloc(sizeof(*extsym_iter)));
2146                        extsym_iter->next = extsym_start;
2147                        extsym_iter->file = optarg;
2148                        extsym_start = extsym_iter;
2149                        break;
2150                case 'm':
2151                        modversions = 1;
2152                        break;
2153                case 'o':
2154                        dump_write = optarg;
2155                        break;
2156                case 'a':
2157                        all_versions = 1;
2158                        break;
2159                case 's':
2160                        vmlinux_section_warnings = 0;
2161                        break;
2162                case 'S':
2163                        sec_mismatch_verbose = 0;
2164                        break;
2165                case 'w':
2166                        warn_unresolved = 1;
2167                        break;
2168                default:
2169                        exit(1);
2170                }
2171        }
2172
2173        if (kernel_read)
2174                read_dump(kernel_read, 1);
2175        if (module_read)
2176                read_dump(module_read, 0);
2177        while (extsym_start) {
2178                read_dump(extsym_start->file, 0);
2179                extsym_iter = extsym_start->next;
2180                free(extsym_start);
2181                extsym_start = extsym_iter;
2182        }
2183
2184        while (optind < argc)
2185                read_symbols(argv[optind++]);
2186
2187        for (mod = modules; mod; mod = mod->next) {
2188                if (mod->skip)
2189                        continue;
2190                check_exports(mod);
2191        }
2192
2193        err = 0;
2194
2195        for (mod = modules; mod; mod = mod->next) {
2196                char fname[strlen(mod->name) + 10];
2197
2198                if (mod->skip)
2199                        continue;
2200
2201                buf.pos = 0;
2202
2203                add_header(&buf, mod);
2204                add_intree_flag(&buf, !external_module);
2205                add_staging_flag(&buf, mod->name);
2206                err |= add_versions(&buf, mod);
2207                add_depends(&buf, mod, modules);
2208                add_moddevtable(&buf, mod);
2209                add_srcversion(&buf, mod);
2210
2211                sprintf(fname, "%s.mod.c", mod->name);
2212                write_if_changed(&buf, fname);
2213        }
2214
2215        if (dump_write)
2216                write_dump(dump_write);
2217        if (sec_mismatch_count && !sec_mismatch_verbose)
2218                warn("modpost: Found %d section mismatch(es).\n"
2219                     "To see full details build your kernel with:\n"
2220                     "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2221                     sec_mismatch_count);
2222
2223        return err;
2224}
2225
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.