linux/kernel/module.c
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   1/*
   2   Copyright (C) 2002 Richard Henderson
   3   Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software
  17    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18*/
  19#include <linux/export.h>
  20#include <linux/moduleloader.h>
  21#include <linux/ftrace_event.h>
  22#include <linux/init.h>
  23#include <linux/kallsyms.h>
  24#include <linux/file.h>
  25#include <linux/fs.h>
  26#include <linux/sysfs.h>
  27#include <linux/kernel.h>
  28#include <linux/slab.h>
  29#include <linux/vmalloc.h>
  30#include <linux/elf.h>
  31#include <linux/proc_fs.h>
  32#include <linux/security.h>
  33#include <linux/seq_file.h>
  34#include <linux/syscalls.h>
  35#include <linux/fcntl.h>
  36#include <linux/rcupdate.h>
  37#include <linux/capability.h>
  38#include <linux/cpu.h>
  39#include <linux/moduleparam.h>
  40#include <linux/errno.h>
  41#include <linux/err.h>
  42#include <linux/vermagic.h>
  43#include <linux/notifier.h>
  44#include <linux/sched.h>
  45#include <linux/stop_machine.h>
  46#include <linux/device.h>
  47#include <linux/string.h>
  48#include <linux/mutex.h>
  49#include <linux/rculist.h>
  50#include <asm/uaccess.h>
  51#include <asm/cacheflush.h>
  52#include <asm/mmu_context.h>
  53#include <linux/license.h>
  54#include <asm/sections.h>
  55#include <linux/tracepoint.h>
  56#include <linux/ftrace.h>
  57#include <linux/async.h>
  58#include <linux/percpu.h>
  59#include <linux/kmemleak.h>
  60#include <linux/jump_label.h>
  61#include <linux/pfn.h>
  62#include <linux/bsearch.h>
  63#include <linux/fips.h>
  64#include <uapi/linux/module.h>
  65#include "module-internal.h"
  66
  67#define CREATE_TRACE_POINTS
  68#include <trace/events/module.h>
  69
  70#ifndef ARCH_SHF_SMALL
  71#define ARCH_SHF_SMALL 0
  72#endif
  73
  74/*
  75 * Modules' sections will be aligned on page boundaries
  76 * to ensure complete separation of code and data, but
  77 * only when CONFIG_DEBUG_SET_MODULE_RONX=y
  78 */
  79#ifdef CONFIG_DEBUG_SET_MODULE_RONX
  80# define debug_align(X) ALIGN(X, PAGE_SIZE)
  81#else
  82# define debug_align(X) (X)
  83#endif
  84
  85/*
  86 * Given BASE and SIZE this macro calculates the number of pages the
  87 * memory regions occupies
  88 */
  89#define MOD_NUMBER_OF_PAGES(BASE, SIZE) (((SIZE) > 0) ?         \
  90                (PFN_DOWN((unsigned long)(BASE) + (SIZE) - 1) - \
  91                         PFN_DOWN((unsigned long)BASE) + 1)     \
  92                : (0UL))
  93
  94/* If this is set, the section belongs in the init part of the module */
  95#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
  96
  97/*
  98 * Mutex protects:
  99 * 1) List of modules (also safely readable with preempt_disable),
 100 * 2) module_use links,
 101 * 3) module_addr_min/module_addr_max.
 102 * (delete uses stop_machine/add uses RCU list operations). */
 103DEFINE_MUTEX(module_mutex);
 104EXPORT_SYMBOL_GPL(module_mutex);
 105static LIST_HEAD(modules);
 106#ifdef CONFIG_KGDB_KDB
 107struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
 108#endif /* CONFIG_KGDB_KDB */
 109
 110#ifdef CONFIG_MODULE_SIG
 111#ifdef CONFIG_MODULE_SIG_FORCE
 112static bool sig_enforce = true;
 113#else
 114static bool sig_enforce = false;
 115
 116static int param_set_bool_enable_only(const char *val,
 117                                      const struct kernel_param *kp)
 118{
 119        int err;
 120        bool test;
 121        struct kernel_param dummy_kp = *kp;
 122
 123        dummy_kp.arg = &test;
 124
 125        err = param_set_bool(val, &dummy_kp);
 126        if (err)
 127                return err;
 128
 129        /* Don't let them unset it once it's set! */
 130        if (!test && sig_enforce)
 131                return -EROFS;
 132
 133        if (test)
 134                sig_enforce = true;
 135        return 0;
 136}
 137
 138static const struct kernel_param_ops param_ops_bool_enable_only = {
 139        .flags = KERNEL_PARAM_FL_NOARG,
 140        .set = param_set_bool_enable_only,
 141        .get = param_get_bool,
 142};
 143#define param_check_bool_enable_only param_check_bool
 144
 145module_param(sig_enforce, bool_enable_only, 0644);
 146#endif /* !CONFIG_MODULE_SIG_FORCE */
 147#endif /* CONFIG_MODULE_SIG */
 148
 149/* Block module loading/unloading? */
 150int modules_disabled = 0;
 151core_param(nomodule, modules_disabled, bint, 0);
 152
 153/* Waiting for a module to finish initializing? */
 154static DECLARE_WAIT_QUEUE_HEAD(module_wq);
 155
 156static BLOCKING_NOTIFIER_HEAD(module_notify_list);
 157
 158/* Bounds of module allocation, for speeding __module_address.
 159 * Protected by module_mutex. */
 160static unsigned long module_addr_min = -1UL, module_addr_max = 0;
 161
 162int register_module_notifier(struct notifier_block * nb)
 163{
 164        return blocking_notifier_chain_register(&module_notify_list, nb);
 165}
 166EXPORT_SYMBOL(register_module_notifier);
 167
 168int unregister_module_notifier(struct notifier_block * nb)
 169{
 170        return blocking_notifier_chain_unregister(&module_notify_list, nb);
 171}
 172EXPORT_SYMBOL(unregister_module_notifier);
 173
 174struct load_info {
 175        Elf_Ehdr *hdr;
 176        unsigned long len;
 177        Elf_Shdr *sechdrs;
 178        char *secstrings, *strtab;
 179        unsigned long symoffs, stroffs;
 180        struct _ddebug *debug;
 181        unsigned int num_debug;
 182        bool sig_ok;
 183        struct {
 184                unsigned int sym, str, mod, vers, info, pcpu;
 185        } index;
 186};
 187
 188/* We require a truly strong try_module_get(): 0 means failure due to
 189   ongoing or failed initialization etc. */
 190static inline int strong_try_module_get(struct module *mod)
 191{
 192        BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
 193        if (mod && mod->state == MODULE_STATE_COMING)
 194                return -EBUSY;
 195        if (try_module_get(mod))
 196                return 0;
 197        else
 198                return -ENOENT;
 199}
 200
 201static inline void add_taint_module(struct module *mod, unsigned flag,
 202                                    enum lockdep_ok lockdep_ok)
 203{
 204        add_taint(flag, lockdep_ok);
 205        mod->taints |= (1U << flag);
 206}
 207
 208/*
 209 * A thread that wants to hold a reference to a module only while it
 210 * is running can call this to safely exit.  nfsd and lockd use this.
 211 */
 212void __module_put_and_exit(struct module *mod, long code)
 213{
 214        module_put(mod);
 215        do_exit(code);
 216}
 217EXPORT_SYMBOL(__module_put_and_exit);
 218
 219/* Find a module section: 0 means not found. */
 220static unsigned int find_sec(const struct load_info *info, const char *name)
 221{
 222        unsigned int i;
 223
 224        for (i = 1; i < info->hdr->e_shnum; i++) {
 225                Elf_Shdr *shdr = &info->sechdrs[i];
 226                /* Alloc bit cleared means "ignore it." */
 227                if ((shdr->sh_flags & SHF_ALLOC)
 228                    && strcmp(info->secstrings + shdr->sh_name, name) == 0)
 229                        return i;
 230        }
 231        return 0;
 232}
 233
 234/* Find a module section, or NULL. */
 235static void *section_addr(const struct load_info *info, const char *name)
 236{
 237        /* Section 0 has sh_addr 0. */
 238        return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
 239}
 240
 241/* Find a module section, or NULL.  Fill in number of "objects" in section. */
 242static void *section_objs(const struct load_info *info,
 243                          const char *name,
 244                          size_t object_size,
 245                          unsigned int *num)
 246{
 247        unsigned int sec = find_sec(info, name);
 248
 249        /* Section 0 has sh_addr 0 and sh_size 0. */
 250        *num = info->sechdrs[sec].sh_size / object_size;
 251        return (void *)info->sechdrs[sec].sh_addr;
 252}
 253
 254/* Provided by the linker */
 255extern const struct kernel_symbol __start___ksymtab[];
 256extern const struct kernel_symbol __stop___ksymtab[];
 257extern const struct kernel_symbol __start___ksymtab_gpl[];
 258extern const struct kernel_symbol __stop___ksymtab_gpl[];
 259extern const struct kernel_symbol __start___ksymtab_gpl_future[];
 260extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
 261extern const unsigned long __start___kcrctab[];
 262extern const unsigned long __start___kcrctab_gpl[];
 263extern const unsigned long __start___kcrctab_gpl_future[];
 264#ifdef CONFIG_UNUSED_SYMBOLS
 265extern const struct kernel_symbol __start___ksymtab_unused[];
 266extern const struct kernel_symbol __stop___ksymtab_unused[];
 267extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
 268extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
 269extern const unsigned long __start___kcrctab_unused[];
 270extern const unsigned long __start___kcrctab_unused_gpl[];
 271#endif
 272
 273#ifndef CONFIG_MODVERSIONS
 274#define symversion(base, idx) NULL
 275#else
 276#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
 277#endif
 278
 279static bool each_symbol_in_section(const struct symsearch *arr,
 280                                   unsigned int arrsize,
 281                                   struct module *owner,
 282                                   bool (*fn)(const struct symsearch *syms,
 283                                              struct module *owner,
 284                                              void *data),
 285                                   void *data)
 286{
 287        unsigned int j;
 288
 289        for (j = 0; j < arrsize; j++) {
 290                if (fn(&arr[j], owner, data))
 291                        return true;
 292        }
 293
 294        return false;
 295}
 296
 297/* Returns true as soon as fn returns true, otherwise false. */
 298bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
 299                                    struct module *owner,
 300                                    void *data),
 301                         void *data)
 302{
 303        struct module *mod;
 304        static const struct symsearch arr[] = {
 305                { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
 306                  NOT_GPL_ONLY, false },
 307                { __start___ksymtab_gpl, __stop___ksymtab_gpl,
 308                  __start___kcrctab_gpl,
 309                  GPL_ONLY, false },
 310                { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
 311                  __start___kcrctab_gpl_future,
 312                  WILL_BE_GPL_ONLY, false },
 313#ifdef CONFIG_UNUSED_SYMBOLS
 314                { __start___ksymtab_unused, __stop___ksymtab_unused,
 315                  __start___kcrctab_unused,
 316                  NOT_GPL_ONLY, true },
 317                { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
 318                  __start___kcrctab_unused_gpl,
 319                  GPL_ONLY, true },
 320#endif
 321        };
 322
 323        if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
 324                return true;
 325
 326        list_for_each_entry_rcu(mod, &modules, list) {
 327                struct symsearch arr[] = {
 328                        { mod->syms, mod->syms + mod->num_syms, mod->crcs,
 329                          NOT_GPL_ONLY, false },
 330                        { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
 331                          mod->gpl_crcs,
 332                          GPL_ONLY, false },
 333                        { mod->gpl_future_syms,
 334                          mod->gpl_future_syms + mod->num_gpl_future_syms,
 335                          mod->gpl_future_crcs,
 336                          WILL_BE_GPL_ONLY, false },
 337#ifdef CONFIG_UNUSED_SYMBOLS
 338                        { mod->unused_syms,
 339                          mod->unused_syms + mod->num_unused_syms,
 340                          mod->unused_crcs,
 341                          NOT_GPL_ONLY, true },
 342                        { mod->unused_gpl_syms,
 343                          mod->unused_gpl_syms + mod->num_unused_gpl_syms,
 344                          mod->unused_gpl_crcs,
 345                          GPL_ONLY, true },
 346#endif
 347                };
 348
 349                if (mod->state == MODULE_STATE_UNFORMED)
 350                        continue;
 351
 352                if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
 353                        return true;
 354        }
 355        return false;
 356}
 357EXPORT_SYMBOL_GPL(each_symbol_section);
 358
 359struct find_symbol_arg {
 360        /* Input */
 361        const char *name;
 362        bool gplok;
 363        bool warn;
 364
 365        /* Output */
 366        struct module *owner;
 367        const unsigned long *crc;
 368        const struct kernel_symbol *sym;
 369};
 370
 371static bool check_symbol(const struct symsearch *syms,
 372                                 struct module *owner,
 373                                 unsigned int symnum, void *data)
 374{
 375        struct find_symbol_arg *fsa = data;
 376
 377        if (!fsa->gplok) {
 378                if (syms->licence == GPL_ONLY)
 379                        return false;
 380                if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
 381                        printk(KERN_WARNING "Symbol %s is being used "
 382                               "by a non-GPL module, which will not "
 383                               "be allowed in the future\n", fsa->name);
 384                }
 385        }
 386
 387#ifdef CONFIG_UNUSED_SYMBOLS
 388        if (syms->unused && fsa->warn) {
 389                printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
 390                       "however this module is using it.\n", fsa->name);
 391                printk(KERN_WARNING
 392                       "This symbol will go away in the future.\n");
 393                printk(KERN_WARNING
 394                       "Please evalute if this is the right api to use and if "
 395                       "it really is, submit a report the linux kernel "
 396                       "mailinglist together with submitting your code for "
 397                       "inclusion.\n");
 398        }
 399#endif
 400
 401        fsa->owner = owner;
 402        fsa->crc = symversion(syms->crcs, symnum);
 403        fsa->sym = &syms->start[symnum];
 404        return true;
 405}
 406
 407static int cmp_name(const void *va, const void *vb)
 408{
 409        const char *a;
 410        const struct kernel_symbol *b;
 411        a = va; b = vb;
 412        return strcmp(a, b->name);
 413}
 414
 415static bool find_symbol_in_section(const struct symsearch *syms,
 416                                   struct module *owner,
 417                                   void *data)
 418{
 419        struct find_symbol_arg *fsa = data;
 420        struct kernel_symbol *sym;
 421
 422        sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
 423                        sizeof(struct kernel_symbol), cmp_name);
 424
 425        if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
 426                return true;
 427
 428        return false;
 429}
 430
 431/* Find a symbol and return it, along with, (optional) crc and
 432 * (optional) module which owns it.  Needs preempt disabled or module_mutex. */
 433const struct kernel_symbol *find_symbol(const char *name,
 434                                        struct module **owner,
 435                                        const unsigned long **crc,
 436                                        bool gplok,
 437                                        bool warn)
 438{
 439        struct find_symbol_arg fsa;
 440
 441        fsa.name = name;
 442        fsa.gplok = gplok;
 443        fsa.warn = warn;
 444
 445        if (each_symbol_section(find_symbol_in_section, &fsa)) {
 446                if (owner)
 447                        *owner = fsa.owner;
 448                if (crc)
 449                        *crc = fsa.crc;
 450                return fsa.sym;
 451        }
 452
 453        pr_debug("Failed to find symbol %s\n", name);
 454        return NULL;
 455}
 456EXPORT_SYMBOL_GPL(find_symbol);
 457
 458/* Search for module by name: must hold module_mutex. */
 459static struct module *find_module_all(const char *name, size_t len,
 460                                      bool even_unformed)
 461{
 462        struct module *mod;
 463
 464        list_for_each_entry(mod, &modules, list) {
 465                if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
 466                        continue;
 467                if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
 468                        return mod;
 469        }
 470        return NULL;
 471}
 472
 473struct module *find_module(const char *name)
 474{
 475        return find_module_all(name, strlen(name), false);
 476}
 477EXPORT_SYMBOL_GPL(find_module);
 478
 479#ifdef CONFIG_SMP
 480
 481static inline void __percpu *mod_percpu(struct module *mod)
 482{
 483        return mod->percpu;
 484}
 485
 486static int percpu_modalloc(struct module *mod, struct load_info *info)
 487{
 488        Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
 489        unsigned long align = pcpusec->sh_addralign;
 490
 491        if (!pcpusec->sh_size)
 492                return 0;
 493
 494        if (align > PAGE_SIZE) {
 495                printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
 496                       mod->name, align, PAGE_SIZE);
 497                align = PAGE_SIZE;
 498        }
 499
 500        mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
 501        if (!mod->percpu) {
 502                printk(KERN_WARNING
 503                       "%s: Could not allocate %lu bytes percpu data\n",
 504                       mod->name, (unsigned long)pcpusec->sh_size);
 505                return -ENOMEM;
 506        }
 507        mod->percpu_size = pcpusec->sh_size;
 508        return 0;
 509}
 510
 511static void percpu_modfree(struct module *mod)
 512{
 513        free_percpu(mod->percpu);
 514}
 515
 516static unsigned int find_pcpusec(struct load_info *info)
 517{
 518        return find_sec(info, ".data..percpu");
 519}
 520
 521static void percpu_modcopy(struct module *mod,
 522                           const void *from, unsigned long size)
 523{
 524        int cpu;
 525
 526        for_each_possible_cpu(cpu)
 527                memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
 528}
 529
 530/**
 531 * is_module_percpu_address - test whether address is from module static percpu
 532 * @addr: address to test
 533 *
 534 * Test whether @addr belongs to module static percpu area.
 535 *
 536 * RETURNS:
 537 * %true if @addr is from module static percpu area
 538 */
 539bool is_module_percpu_address(unsigned long addr)
 540{
 541        struct module *mod;
 542        unsigned int cpu;
 543
 544        preempt_disable();
 545
 546        list_for_each_entry_rcu(mod, &modules, list) {
 547                if (mod->state == MODULE_STATE_UNFORMED)
 548                        continue;
 549                if (!mod->percpu_size)
 550                        continue;
 551                for_each_possible_cpu(cpu) {
 552                        void *start = per_cpu_ptr(mod->percpu, cpu);
 553
 554                        if ((void *)addr >= start &&
 555                            (void *)addr < start + mod->percpu_size) {
 556                                preempt_enable();
 557                                return true;
 558                        }
 559                }
 560        }
 561
 562        preempt_enable();
 563        return false;
 564}
 565
 566#else /* ... !CONFIG_SMP */
 567
 568static inline void __percpu *mod_percpu(struct module *mod)
 569{
 570        return NULL;
 571}
 572static int percpu_modalloc(struct module *mod, struct load_info *info)
 573{
 574        /* UP modules shouldn't have this section: ENOMEM isn't quite right */
 575        if (info->sechdrs[info->index.pcpu].sh_size != 0)
 576                return -ENOMEM;
 577        return 0;
 578}
 579static inline void percpu_modfree(struct module *mod)
 580{
 581}
 582static unsigned int find_pcpusec(struct load_info *info)
 583{
 584        return 0;
 585}
 586static inline void percpu_modcopy(struct module *mod,
 587                                  const void *from, unsigned long size)
 588{
 589        /* pcpusec should be 0, and size of that section should be 0. */
 590        BUG_ON(size != 0);
 591}
 592bool is_module_percpu_address(unsigned long addr)
 593{
 594        return false;
 595}
 596
 597#endif /* CONFIG_SMP */
 598
 599#define MODINFO_ATTR(field)     \
 600static void setup_modinfo_##field(struct module *mod, const char *s)  \
 601{                                                                     \
 602        mod->field = kstrdup(s, GFP_KERNEL);                          \
 603}                                                                     \
 604static ssize_t show_modinfo_##field(struct module_attribute *mattr,   \
 605                        struct module_kobject *mk, char *buffer)      \
 606{                                                                     \
 607        return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field);  \
 608}                                                                     \
 609static int modinfo_##field##_exists(struct module *mod)               \
 610{                                                                     \
 611        return mod->field != NULL;                                    \
 612}                                                                     \
 613static void free_modinfo_##field(struct module *mod)                  \
 614{                                                                     \
 615        kfree(mod->field);                                            \
 616        mod->field = NULL;                                            \
 617}                                                                     \
 618static struct module_attribute modinfo_##field = {                    \
 619        .attr = { .name = __stringify(field), .mode = 0444 },         \
 620        .show = show_modinfo_##field,                                 \
 621        .setup = setup_modinfo_##field,                               \
 622        .test = modinfo_##field##_exists,                             \
 623        .free = free_modinfo_##field,                                 \
 624};
 625
 626MODINFO_ATTR(version);
 627MODINFO_ATTR(srcversion);
 628
 629static char last_unloaded_module[MODULE_NAME_LEN+1];
 630
 631#ifdef CONFIG_MODULE_UNLOAD
 632
 633EXPORT_TRACEPOINT_SYMBOL(module_get);
 634
 635/* Init the unload section of the module. */
 636static int module_unload_init(struct module *mod)
 637{
 638        mod->refptr = alloc_percpu(struct module_ref);
 639        if (!mod->refptr)
 640                return -ENOMEM;
 641
 642        INIT_LIST_HEAD(&mod->source_list);
 643        INIT_LIST_HEAD(&mod->target_list);
 644
 645        /* Hold reference count during initialization. */
 646        __this_cpu_write(mod->refptr->incs, 1);
 647        /* Backwards compatibility macros put refcount during init. */
 648        mod->waiter = current;
 649
 650        return 0;
 651}
 652
 653/* Does a already use b? */
 654static int already_uses(struct module *a, struct module *b)
 655{
 656        struct module_use *use;
 657
 658        list_for_each_entry(use, &b->source_list, source_list) {
 659                if (use->source == a) {
 660                        pr_debug("%s uses %s!\n", a->name, b->name);
 661                        return 1;
 662                }
 663        }
 664        pr_debug("%s does not use %s!\n", a->name, b->name);
 665        return 0;
 666}
 667
 668/*
 669 * Module a uses b
 670 *  - we add 'a' as a "source", 'b' as a "target" of module use
 671 *  - the module_use is added to the list of 'b' sources (so
 672 *    'b' can walk the list to see who sourced them), and of 'a'
 673 *    targets (so 'a' can see what modules it targets).
 674 */
 675static int add_module_usage(struct module *a, struct module *b)
 676{
 677        struct module_use *use;
 678
 679        pr_debug("Allocating new usage for %s.\n", a->name);
 680        use = kmalloc(sizeof(*use), GFP_ATOMIC);
 681        if (!use) {
 682                printk(KERN_WARNING "%s: out of memory loading\n", a->name);
 683                return -ENOMEM;
 684        }
 685
 686        use->source = a;
 687        use->target = b;
 688        list_add(&use->source_list, &b->source_list);
 689        list_add(&use->target_list, &a->target_list);
 690        return 0;
 691}
 692
 693/* Module a uses b: caller needs module_mutex() */
 694int ref_module(struct module *a, struct module *b)
 695{
 696        int err;
 697
 698        if (b == NULL || already_uses(a, b))
 699                return 0;
 700
 701        /* If module isn't available, we fail. */
 702        err = strong_try_module_get(b);
 703        if (err)
 704                return err;
 705
 706        err = add_module_usage(a, b);
 707        if (err) {
 708                module_put(b);
 709                return err;
 710        }
 711        return 0;
 712}
 713EXPORT_SYMBOL_GPL(ref_module);
 714
 715/* Clear the unload stuff of the module. */
 716static void module_unload_free(struct module *mod)
 717{
 718        struct module_use *use, *tmp;
 719
 720        mutex_lock(&module_mutex);
 721        list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
 722                struct module *i = use->target;
 723                pr_debug("%s unusing %s\n", mod->name, i->name);
 724                module_put(i);
 725                list_del(&use->source_list);
 726                list_del(&use->target_list);
 727                kfree(use);
 728        }
 729        mutex_unlock(&module_mutex);
 730
 731        free_percpu(mod->refptr);
 732}
 733
 734#ifdef CONFIG_MODULE_FORCE_UNLOAD
 735static inline int try_force_unload(unsigned int flags)
 736{
 737        int ret = (flags & O_TRUNC);
 738        if (ret)
 739                add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
 740        return ret;
 741}
 742#else
 743static inline int try_force_unload(unsigned int flags)
 744{
 745        return 0;
 746}
 747#endif /* CONFIG_MODULE_FORCE_UNLOAD */
 748
 749struct stopref
 750{
 751        struct module *mod;
 752        int flags;
 753        int *forced;
 754};
 755
 756/* Whole machine is stopped with interrupts off when this runs. */
 757static int __try_stop_module(void *_sref)
 758{
 759        struct stopref *sref = _sref;
 760
 761        /* If it's not unused, quit unless we're forcing. */
 762        if (module_refcount(sref->mod) != 0) {
 763                if (!(*sref->forced = try_force_unload(sref->flags)))
 764                        return -EWOULDBLOCK;
 765        }
 766
 767        /* Mark it as dying. */
 768        sref->mod->state = MODULE_STATE_GOING;
 769        return 0;
 770}
 771
 772static int try_stop_module(struct module *mod, int flags, int *forced)
 773{
 774        if (flags & O_NONBLOCK) {
 775                struct stopref sref = { mod, flags, forced };
 776
 777                return stop_machine(__try_stop_module, &sref, NULL);
 778        } else {
 779                /* We don't need to stop the machine for this. */
 780                mod->state = MODULE_STATE_GOING;
 781                synchronize_sched();
 782                return 0;
 783        }
 784}
 785
 786unsigned long module_refcount(struct module *mod)
 787{
 788        unsigned long incs = 0, decs = 0;
 789        int cpu;
 790
 791        for_each_possible_cpu(cpu)
 792                decs += per_cpu_ptr(mod->refptr, cpu)->decs;
 793        /*
 794         * ensure the incs are added up after the decs.
 795         * module_put ensures incs are visible before decs with smp_wmb.
 796         *
 797         * This 2-count scheme avoids the situation where the refcount
 798         * for CPU0 is read, then CPU0 increments the module refcount,
 799         * then CPU1 drops that refcount, then the refcount for CPU1 is
 800         * read. We would record a decrement but not its corresponding
 801         * increment so we would see a low count (disaster).
 802         *
 803         * Rare situation? But module_refcount can be preempted, and we
 804         * might be tallying up 4096+ CPUs. So it is not impossible.
 805         */
 806        smp_rmb();
 807        for_each_possible_cpu(cpu)
 808                incs += per_cpu_ptr(mod->refptr, cpu)->incs;
 809        return incs - decs;
 810}
 811EXPORT_SYMBOL(module_refcount);
 812
 813/* This exists whether we can unload or not */
 814static void free_module(struct module *mod);
 815
 816static void wait_for_zero_refcount(struct module *mod)
 817{
 818        /* Since we might sleep for some time, release the mutex first */
 819        mutex_unlock(&module_mutex);
 820        for (;;) {
 821                pr_debug("Looking at refcount...\n");
 822                set_current_state(TASK_UNINTERRUPTIBLE);
 823                if (module_refcount(mod) == 0)
 824                        break;
 825                schedule();
 826        }
 827        current->state = TASK_RUNNING;
 828        mutex_lock(&module_mutex);
 829}
 830
 831SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 832                unsigned int, flags)
 833{
 834        struct module *mod;
 835        char name[MODULE_NAME_LEN];
 836        int ret, forced = 0;
 837
 838        if (!capable(CAP_SYS_MODULE) || modules_disabled)
 839                return -EPERM;
 840
 841        if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
 842                return -EFAULT;
 843        name[MODULE_NAME_LEN-1] = '\0';
 844
 845        if (mutex_lock_interruptible(&module_mutex) != 0)
 846                return -EINTR;
 847
 848        mod = find_module(name);
 849        if (!mod) {
 850                ret = -ENOENT;
 851                goto out;
 852        }
 853
 854        if (!list_empty(&mod->source_list)) {
 855                /* Other modules depend on us: get rid of them first. */
 856                ret = -EWOULDBLOCK;
 857                goto out;
 858        }
 859
 860        /* Doing init or already dying? */
 861        if (mod->state != MODULE_STATE_LIVE) {
 862                /* FIXME: if (force), slam module count and wake up
 863                   waiter --RR */
 864                pr_debug("%s already dying\n", mod->name);
 865                ret = -EBUSY;
 866                goto out;
 867        }
 868
 869        /* If it has an init func, it must have an exit func to unload */
 870        if (mod->init && !mod->exit) {
 871                forced = try_force_unload(flags);
 872                if (!forced) {
 873                        /* This module can't be removed */
 874                        ret = -EBUSY;
 875                        goto out;
 876                }
 877        }
 878
 879        /* Set this up before setting mod->state */
 880        mod->waiter = current;
 881
 882        /* Stop the machine so refcounts can't move and disable module. */
 883        ret = try_stop_module(mod, flags, &forced);
 884        if (ret != 0)
 885                goto out;
 886
 887        /* Never wait if forced. */
 888        if (!forced && module_refcount(mod) != 0)
 889                wait_for_zero_refcount(mod);
 890
 891        mutex_unlock(&module_mutex);
 892        /* Final destruction now no one is using it. */
 893        if (mod->exit != NULL)
 894                mod->exit();
 895        blocking_notifier_call_chain(&module_notify_list,
 896                                     MODULE_STATE_GOING, mod);
 897        async_synchronize_full();
 898
 899        /* Store the name of the last unloaded module for diagnostic purposes */
 900        strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
 901
 902        free_module(mod);
 903        return 0;
 904out:
 905        mutex_unlock(&module_mutex);
 906        return ret;
 907}
 908
 909static inline void print_unload_info(struct seq_file *m, struct module *mod)
 910{
 911        struct module_use *use;
 912        int printed_something = 0;
 913
 914        seq_printf(m, " %lu ", module_refcount(mod));
 915
 916        /* Always include a trailing , so userspace can differentiate
 917           between this and the old multi-field proc format. */
 918        list_for_each_entry(use, &mod->source_list, source_list) {
 919                printed_something = 1;
 920                seq_printf(m, "%s,", use->source->name);
 921        }
 922
 923        if (mod->init != NULL && mod->exit == NULL) {
 924                printed_something = 1;
 925                seq_printf(m, "[permanent],");
 926        }
 927
 928        if (!printed_something)
 929                seq_printf(m, "-");
 930}
 931
 932void __symbol_put(const char *symbol)
 933{
 934        struct module *owner;
 935
 936        preempt_disable();
 937        if (!find_symbol(symbol, &owner, NULL, true, false))
 938                BUG();
 939        module_put(owner);
 940        preempt_enable();
 941}
 942EXPORT_SYMBOL(__symbol_put);
 943
 944/* Note this assumes addr is a function, which it currently always is. */
 945void symbol_put_addr(void *addr)
 946{
 947        struct module *modaddr;
 948        unsigned long a = (unsigned long)dereference_function_descriptor(addr);
 949
 950        if (core_kernel_text(a))
 951                return;
 952
 953        /* module_text_address is safe here: we're supposed to have reference
 954         * to module from symbol_get, so it can't go away. */
 955        modaddr = __module_text_address(a);
 956        BUG_ON(!modaddr);
 957        module_put(modaddr);
 958}
 959EXPORT_SYMBOL_GPL(symbol_put_addr);
 960
 961static ssize_t show_refcnt(struct module_attribute *mattr,
 962                           struct module_kobject *mk, char *buffer)
 963{
 964        return sprintf(buffer, "%lu\n", module_refcount(mk->mod));
 965}
 966
 967static struct module_attribute modinfo_refcnt =
 968        __ATTR(refcnt, 0444, show_refcnt, NULL);
 969
 970void __module_get(struct module *module)
 971{
 972        if (module) {
 973                preempt_disable();
 974                __this_cpu_inc(module->refptr->incs);
 975                trace_module_get(module, _RET_IP_);
 976                preempt_enable();
 977        }
 978}
 979EXPORT_SYMBOL(__module_get);
 980
 981bool try_module_get(struct module *module)
 982{
 983        bool ret = true;
 984
 985        if (module) {
 986                preempt_disable();
 987
 988                if (likely(module_is_live(module))) {
 989                        __this_cpu_inc(module->refptr->incs);
 990                        trace_module_get(module, _RET_IP_);
 991                } else
 992                        ret = false;
 993
 994                preempt_enable();
 995        }
 996        return ret;
 997}
 998EXPORT_SYMBOL(try_module_get);
 999
1000void module_put(struct module *module)
1001{
1002        if (module) {
1003                preempt_disable();
1004                smp_wmb(); /* see comment in module_refcount */
1005                __this_cpu_inc(module->refptr->decs);
1006
1007                trace_module_put(module, _RET_IP_);
1008                /* Maybe they're waiting for us to drop reference? */
1009                if (unlikely(!module_is_live(module)))
1010                        wake_up_process(module->waiter);
1011                preempt_enable();
1012        }
1013}
1014EXPORT_SYMBOL(module_put);
1015
1016#else /* !CONFIG_MODULE_UNLOAD */
1017static inline void print_unload_info(struct seq_file *m, struct module *mod)
1018{
1019        /* We don't know the usage count, or what modules are using. */
1020        seq_printf(m, " - -");
1021}
1022
1023static inline void module_unload_free(struct module *mod)
1024{
1025}
1026
1027int ref_module(struct module *a, struct module *b)
1028{
1029        return strong_try_module_get(b);
1030}
1031EXPORT_SYMBOL_GPL(ref_module);
1032
1033static inline int module_unload_init(struct module *mod)
1034{
1035        return 0;
1036}
1037#endif /* CONFIG_MODULE_UNLOAD */
1038
1039static size_t module_flags_taint(struct module *mod, char *buf)
1040{
1041        size_t l = 0;
1042
1043        if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
1044                buf[l++] = 'P';
1045        if (mod->taints & (1 << TAINT_OOT_MODULE))
1046                buf[l++] = 'O';
1047        if (mod->taints & (1 << TAINT_FORCED_MODULE))
1048                buf[l++] = 'F';
1049        if (mod->taints & (1 << TAINT_CRAP))
1050                buf[l++] = 'C';
1051        /*
1052         * TAINT_FORCED_RMMOD: could be added.
1053         * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
1054         * apply to modules.
1055         */
1056        return l;
1057}
1058
1059static ssize_t show_initstate(struct module_attribute *mattr,
1060                              struct module_kobject *mk, char *buffer)
1061{
1062        const char *state = "unknown";
1063
1064        switch (mk->mod->state) {
1065        case MODULE_STATE_LIVE:
1066                state = "live";
1067                break;
1068        case MODULE_STATE_COMING:
1069                state = "coming";
1070                break;
1071        case MODULE_STATE_GOING:
1072                state = "going";
1073                break;
1074        default:
1075                BUG();
1076        }
1077        return sprintf(buffer, "%s\n", state);
1078}
1079
1080static struct module_attribute modinfo_initstate =
1081        __ATTR(initstate, 0444, show_initstate, NULL);
1082
1083static ssize_t store_uevent(struct module_attribute *mattr,
1084                            struct module_kobject *mk,
1085                            const char *buffer, size_t count)
1086{
1087        enum kobject_action action;
1088
1089        if (kobject_action_type(buffer, count, &action) == 0)
1090                kobject_uevent(&mk->kobj, action);
1091        return count;
1092}
1093
1094struct module_attribute module_uevent =
1095        __ATTR(uevent, 0200, NULL, store_uevent);
1096
1097static ssize_t show_coresize(struct module_attribute *mattr,
1098                             struct module_kobject *mk, char *buffer)
1099{
1100        return sprintf(buffer, "%u\n", mk->mod->core_size);
1101}
1102
1103static struct module_attribute modinfo_coresize =
1104        __ATTR(coresize, 0444, show_coresize, NULL);
1105
1106static ssize_t show_initsize(struct module_attribute *mattr,
1107                             struct module_kobject *mk, char *buffer)
1108{
1109        return sprintf(buffer, "%u\n", mk->mod->init_size);
1110}
1111
1112static struct module_attribute modinfo_initsize =
1113        __ATTR(initsize, 0444, show_initsize, NULL);
1114
1115static ssize_t show_taint(struct module_attribute *mattr,
1116                          struct module_kobject *mk, char *buffer)
1117{
1118        size_t l;
1119
1120        l = module_flags_taint(mk->mod, buffer);
1121        buffer[l++] = '\n';
1122        return l;
1123}
1124
1125static struct module_attribute modinfo_taint =
1126        __ATTR(taint, 0444, show_taint, NULL);
1127
1128static struct module_attribute *modinfo_attrs[] = {
1129        &module_uevent,
1130        &modinfo_version,
1131        &modinfo_srcversion,
1132        &modinfo_initstate,
1133        &modinfo_coresize,
1134        &modinfo_initsize,
1135        &modinfo_taint,
1136#ifdef CONFIG_MODULE_UNLOAD
1137        &modinfo_refcnt,
1138#endif
1139        NULL,
1140};
1141
1142static const char vermagic[] = VERMAGIC_STRING;
1143
1144static int try_to_force_load(struct module *mod, const char *reason)
1145{
1146#ifdef CONFIG_MODULE_FORCE_LOAD
1147        if (!test_taint(TAINT_FORCED_MODULE))
1148                printk(KERN_WARNING "%s: %s: kernel tainted.\n",
1149                       mod->name, reason);
1150        add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
1151        return 0;
1152#else
1153        return -ENOEXEC;
1154#endif
1155}
1156
1157#ifdef CONFIG_MODVERSIONS
1158/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
1159static unsigned long maybe_relocated(unsigned long crc,
1160                                     const struct module *crc_owner)
1161{
1162#ifdef ARCH_RELOCATES_KCRCTAB
1163        if (crc_owner == NULL)
1164                return crc - (unsigned long)reloc_start;
1165#endif
1166        return crc;
1167}
1168
1169static int check_version(Elf_Shdr *sechdrs,
1170                         unsigned int versindex,
1171                         const char *symname,
1172                         struct module *mod, 
1173                         const unsigned long *crc,
1174                         const struct module *crc_owner)
1175{
1176        unsigned int i, num_versions;
1177        struct modversion_info *versions;
1178
1179        /* Exporting module didn't supply crcs?  OK, we're already tainted. */
1180        if (!crc)
1181                return 1;
1182
1183        /* No versions at all?  modprobe --force does this. */
1184        if (versindex == 0)
1185                return try_to_force_load(mod, symname) == 0;
1186
1187        versions = (void *) sechdrs[versindex].sh_addr;
1188        num_versions = sechdrs[versindex].sh_size
1189                / sizeof(struct modversion_info);
1190
1191        for (i = 0; i < num_versions; i++) {
1192                if (strcmp(versions[i].name, symname) != 0)
1193                        continue;
1194
1195                if (versions[i].crc == maybe_relocated(*crc, crc_owner))
1196                        return 1;
1197                pr_debug("Found checksum %lX vs module %lX\n",
1198                       maybe_relocated(*crc, crc_owner), versions[i].crc);
1199                goto bad_version;
1200        }
1201
1202        printk(KERN_WARNING "%s: no symbol version for %s\n",
1203               mod->name, symname);
1204        return 0;
1205
1206bad_version:
1207        printk("%s: disagrees about version of symbol %s\n",
1208               mod->name, symname);
1209        return 0;
1210}
1211
1212static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1213                                          unsigned int versindex,
1214                                          struct module *mod)
1215{
1216        const unsigned long *crc;
1217
1218        /* Since this should be found in kernel (which can't be removed),
1219         * no locking is necessary. */
1220        if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
1221                         &crc, true, false))
1222                BUG();
1223        return check_version(sechdrs, versindex,
1224                             VMLINUX_SYMBOL_STR(module_layout), mod, crc,
1225                             NULL);
1226}
1227
1228/* First part is kernel version, which we ignore if module has crcs. */
1229static inline int same_magic(const char *amagic, const char *bmagic,
1230                             bool has_crcs)
1231{
1232        if (has_crcs) {
1233                amagic += strcspn(amagic, " ");
1234                bmagic += strcspn(bmagic, " ");
1235        }
1236        return strcmp(amagic, bmagic) == 0;
1237}
1238#else
1239static inline int check_version(Elf_Shdr *sechdrs,
1240                                unsigned int versindex,
1241                                const char *symname,
1242                                struct module *mod, 
1243                                const unsigned long *crc,
1244                                const struct module *crc_owner)
1245{
1246        return 1;
1247}
1248
1249static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1250                                          unsigned int versindex,
1251                                          struct module *mod)
1252{
1253        return 1;
1254}
1255
1256static inline int same_magic(const char *amagic, const char *bmagic,
1257                             bool has_crcs)
1258{
1259        return strcmp(amagic, bmagic) == 0;
1260}
1261#endif /* CONFIG_MODVERSIONS */
1262
1263/* Resolve a symbol for this module.  I.e. if we find one, record usage. */
1264static const struct kernel_symbol *resolve_symbol(struct module *mod,
1265                                                  const struct load_info *info,
1266                                                  const char *name,
1267                                                  char ownername[])
1268{
1269        struct module *owner;
1270        const struct kernel_symbol *sym;
1271        const unsigned long *crc;
1272        int err;
1273
1274        mutex_lock(&module_mutex);
1275        sym = find_symbol(name, &owner, &crc,
1276                          !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1277        if (!sym)
1278                goto unlock;
1279
1280        if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1281                           owner)) {
1282                sym = ERR_PTR(-EINVAL);
1283                goto getname;
1284        }
1285
1286        err = ref_module(mod, owner);
1287        if (err) {
1288                sym = ERR_PTR(err);
1289                goto getname;
1290        }
1291
1292getname:
1293        /* We must make copy under the lock if we failed to get ref. */
1294        strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1295unlock:
1296        mutex_unlock(&module_mutex);
1297        return sym;
1298}
1299
1300static const struct kernel_symbol *
1301resolve_symbol_wait(struct module *mod,
1302                    const struct load_info *info,
1303                    const char *name)
1304{
1305        const struct kernel_symbol *ksym;
1306        char owner[MODULE_NAME_LEN];
1307
1308        if (wait_event_interruptible_timeout(module_wq,
1309                        !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1310                        || PTR_ERR(ksym) != -EBUSY,
1311                                             30 * HZ) <= 0) {
1312                printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
1313                       mod->name, owner);
1314        }
1315        return ksym;
1316}
1317
1318/*
1319 * /sys/module/foo/sections stuff
1320 * J. Corbet <corbet@lwn.net>
1321 */
1322#ifdef CONFIG_SYSFS
1323
1324#ifdef CONFIG_KALLSYMS
1325static inline bool sect_empty(const Elf_Shdr *sect)
1326{
1327        return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1328}
1329
1330struct module_sect_attr
1331{
1332        struct module_attribute mattr;
1333        char *name;
1334        unsigned long address;
1335};
1336
1337struct module_sect_attrs
1338{
1339        struct attribute_group grp;
1340        unsigned int nsections;
1341        struct module_sect_attr attrs[0];
1342};
1343
1344static ssize_t module_sect_show(struct module_attribute *mattr,
1345                                struct module_kobject *mk, char *buf)
1346{
1347        struct module_sect_attr *sattr =
1348                container_of(mattr, struct module_sect_attr, mattr);
1349        return sprintf(buf, "0x%pK\n", (void *)sattr->address);
1350}
1351
1352static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1353{
1354        unsigned int section;
1355
1356        for (section = 0; section < sect_attrs->nsections; section++)
1357                kfree(sect_attrs->attrs[section].name);
1358        kfree(sect_attrs);
1359}
1360
1361static void add_sect_attrs(struct module *mod, const struct load_info *info)
1362{
1363        unsigned int nloaded = 0, i, size[2];
1364        struct module_sect_attrs *sect_attrs;
1365        struct module_sect_attr *sattr;
1366        struct attribute **gattr;
1367
1368        /* Count loaded sections and allocate structures */
1369        for (i = 0; i < info->hdr->e_shnum; i++)
1370                if (!sect_empty(&info->sechdrs[i]))
1371                        nloaded++;
1372        size[0] = ALIGN(sizeof(*sect_attrs)
1373                        + nloaded * sizeof(sect_attrs->attrs[0]),
1374                        sizeof(sect_attrs->grp.attrs[0]));
1375        size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1376        sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1377        if (sect_attrs == NULL)
1378                return;
1379
1380        /* Setup section attributes. */
1381        sect_attrs->grp.name = "sections";
1382        sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1383
1384        sect_attrs->nsections = 0;
1385        sattr = &sect_attrs->attrs[0];
1386        gattr = &sect_attrs->grp.attrs[0];
1387        for (i = 0; i < info->hdr->e_shnum; i++) {
1388                Elf_Shdr *sec = &info->sechdrs[i];
1389                if (sect_empty(sec))
1390                        continue;
1391                sattr->address = sec->sh_addr;
1392                sattr->name = kstrdup(info->secstrings + sec->sh_name,
1393                                        GFP_KERNEL);
1394                if (sattr->name == NULL)
1395                        goto out;
1396                sect_attrs->nsections++;
1397                sysfs_attr_init(&sattr->mattr.attr);
1398                sattr->mattr.show = module_sect_show;
1399                sattr->mattr.store = NULL;
1400                sattr->mattr.attr.name = sattr->name;
1401                sattr->mattr.attr.mode = S_IRUGO;
1402                *(gattr++) = &(sattr++)->mattr.attr;
1403        }
1404        *gattr = NULL;
1405
1406        if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1407                goto out;
1408
1409        mod->sect_attrs = sect_attrs;
1410        return;
1411  out:
1412        free_sect_attrs(sect_attrs);
1413}
1414
1415static void remove_sect_attrs(struct module *mod)
1416{
1417        if (mod->sect_attrs) {
1418                sysfs_remove_group(&mod->mkobj.kobj,
1419                                   &mod->sect_attrs->grp);
1420                /* We are positive that no one is using any sect attrs
1421                 * at this point.  Deallocate immediately. */
1422                free_sect_attrs(mod->sect_attrs);
1423                mod->sect_attrs = NULL;
1424        }
1425}
1426
1427/*
1428 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1429 */
1430
1431struct module_notes_attrs {
1432        struct kobject *dir;
1433        unsigned int notes;
1434        struct bin_attribute attrs[0];
1435};
1436
1437static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1438                                 struct bin_attribute *bin_attr,
1439                                 char *buf, loff_t pos, size_t count)
1440{
1441        /*
1442         * The caller checked the pos and count against our size.
1443         */
1444        memcpy(buf, bin_attr->private + pos, count);
1445        return count;
1446}
1447
1448static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1449                             unsigned int i)
1450{
1451        if (notes_attrs->dir) {
1452                while (i-- > 0)
1453                        sysfs_remove_bin_file(notes_attrs->dir,
1454                                              &notes_attrs->attrs[i]);
1455                kobject_put(notes_attrs->dir);
1456        }
1457        kfree(notes_attrs);
1458}
1459
1460static void add_notes_attrs(struct module *mod, const struct load_info *info)
1461{
1462        unsigned int notes, loaded, i;
1463        struct module_notes_attrs *notes_attrs;
1464        struct bin_attribute *nattr;
1465
1466        /* failed to create section attributes, so can't create notes */
1467        if (!mod->sect_attrs)
1468                return;
1469
1470        /* Count notes sections and allocate structures.  */
1471        notes = 0;
1472        for (i = 0; i < info->hdr->e_shnum; i++)
1473                if (!sect_empty(&info->sechdrs[i]) &&
1474                    (info->sechdrs[i].sh_type == SHT_NOTE))
1475                        ++notes;
1476
1477        if (notes == 0)
1478                return;
1479
1480        notes_attrs = kzalloc(sizeof(*notes_attrs)
1481                              + notes * sizeof(notes_attrs->attrs[0]),
1482                              GFP_KERNEL);
1483        if (notes_attrs == NULL)
1484                return;
1485
1486        notes_attrs->notes = notes;
1487        nattr = &notes_attrs->attrs[0];
1488        for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1489                if (sect_empty(&info->sechdrs[i]))
1490                        continue;
1491                if (info->sechdrs[i].sh_type == SHT_NOTE) {
1492                        sysfs_bin_attr_init(nattr);
1493                        nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1494                        nattr->attr.mode = S_IRUGO;
1495                        nattr->size = info->sechdrs[i].sh_size;
1496                        nattr->private = (void *) info->sechdrs[i].sh_addr;
1497                        nattr->read = module_notes_read;
1498                        ++nattr;
1499                }
1500                ++loaded;
1501        }
1502
1503        notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1504        if (!notes_attrs->dir)
1505                goto out;
1506
1507        for (i = 0; i < notes; ++i)
1508                if (sysfs_create_bin_file(notes_attrs->dir,
1509                                          &notes_attrs->attrs[i]))
1510                        goto out;
1511
1512        mod->notes_attrs = notes_attrs;
1513        return;
1514
1515  out:
1516        free_notes_attrs(notes_attrs, i);
1517}
1518
1519static void remove_notes_attrs(struct module *mod)
1520{
1521        if (mod->notes_attrs)
1522                free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1523}
1524
1525#else
1526
1527static inline void add_sect_attrs(struct module *mod,
1528                                  const struct load_info *info)
1529{
1530}
1531
1532static inline void remove_sect_attrs(struct module *mod)
1533{
1534}
1535
1536static inline void add_notes_attrs(struct module *mod,
1537                                   const struct load_info *info)
1538{
1539}
1540
1541static inline void remove_notes_attrs(struct module *mod)
1542{
1543}
1544#endif /* CONFIG_KALLSYMS */
1545
1546static void add_usage_links(struct module *mod)
1547{
1548#ifdef CONFIG_MODULE_UNLOAD
1549        struct module_use *use;
1550        int nowarn;
1551
1552        mutex_lock(&module_mutex);
1553        list_for_each_entry(use, &mod->target_list, target_list) {
1554                nowarn = sysfs_create_link(use->target->holders_dir,
1555                                           &mod->mkobj.kobj, mod->name);
1556        }
1557        mutex_unlock(&module_mutex);
1558#endif
1559}
1560
1561static void del_usage_links(struct module *mod)
1562{
1563#ifdef CONFIG_MODULE_UNLOAD
1564        struct module_use *use;
1565
1566        mutex_lock(&module_mutex);
1567        list_for_each_entry(use, &mod->target_list, target_list)
1568                sysfs_remove_link(use->target->holders_dir, mod->name);
1569        mutex_unlock(&module_mutex);
1570#endif
1571}
1572
1573static int module_add_modinfo_attrs(struct module *mod)
1574{
1575        struct module_attribute *attr;
1576        struct module_attribute *temp_attr;
1577        int error = 0;
1578        int i;
1579
1580        mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1581                                        (ARRAY_SIZE(modinfo_attrs) + 1)),
1582                                        GFP_KERNEL);
1583        if (!mod->modinfo_attrs)
1584                return -ENOMEM;
1585
1586        temp_attr = mod->modinfo_attrs;
1587        for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1588                if (!attr->test ||
1589                    (attr->test && attr->test(mod))) {
1590                        memcpy(temp_attr, attr, sizeof(*temp_attr));
1591                        sysfs_attr_init(&temp_attr->attr);
1592                        error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1593                        ++temp_attr;
1594                }
1595        }
1596        return error;
1597}
1598
1599static void module_remove_modinfo_attrs(struct module *mod)
1600{
1601        struct module_attribute *attr;
1602        int i;
1603
1604        for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1605                /* pick a field to test for end of list */
1606                if (!attr->attr.name)
1607                        break;
1608                sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1609                if (attr->free)
1610                        attr->free(mod);
1611        }
1612        kfree(mod->modinfo_attrs);
1613}
1614
1615static void mod_kobject_put(struct module *mod)
1616{
1617        DECLARE_COMPLETION_ONSTACK(c);
1618        mod->mkobj.kobj_completion = &c;
1619        kobject_put(&mod->mkobj.kobj);
1620        wait_for_completion(&c);
1621}
1622
1623static int mod_sysfs_init(struct module *mod)
1624{
1625        int err;
1626        struct kobject *kobj;
1627
1628        if (!module_sysfs_initialized) {
1629                printk(KERN_ERR "%s: module sysfs not initialized\n",
1630                       mod->name);
1631                err = -EINVAL;
1632                goto out;
1633        }
1634
1635        kobj = kset_find_obj(module_kset, mod->name);
1636        if (kobj) {
1637                printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1638                kobject_put(kobj);
1639                err = -EINVAL;
1640                goto out;
1641        }
1642
1643        mod->mkobj.mod = mod;
1644
1645        memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1646        mod->mkobj.kobj.kset = module_kset;
1647        err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1648                                   "%s", mod->name);
1649        if (err)
1650                mod_kobject_put(mod);
1651
1652        /* delay uevent until full sysfs population */
1653out:
1654        return err;
1655}
1656
1657static int mod_sysfs_setup(struct module *mod,
1658                           const struct load_info *info,
1659                           struct kernel_param *kparam,
1660                           unsigned int num_params)
1661{
1662        int err;
1663
1664        err = mod_sysfs_init(mod);
1665        if (err)
1666                goto out;
1667
1668        mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1669        if (!mod->holders_dir) {
1670                err = -ENOMEM;
1671                goto out_unreg;
1672        }
1673
1674        err = module_param_sysfs_setup(mod, kparam, num_params);
1675        if (err)
1676                goto out_unreg_holders;
1677
1678        err = module_add_modinfo_attrs(mod);
1679        if (err)
1680                goto out_unreg_param;
1681
1682        add_usage_links(mod);
1683        add_sect_attrs(mod, info);
1684        add_notes_attrs(mod, info);
1685
1686        kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1687        return 0;
1688
1689out_unreg_param:
1690        module_param_sysfs_remove(mod);
1691out_unreg_holders:
1692        kobject_put(mod->holders_dir);
1693out_unreg:
1694        mod_kobject_put(mod);
1695out:
1696        return err;
1697}
1698
1699static void mod_sysfs_fini(struct module *mod)
1700{
1701        remove_notes_attrs(mod);
1702        remove_sect_attrs(mod);
1703        mod_kobject_put(mod);
1704}
1705
1706#else /* !CONFIG_SYSFS */
1707
1708static int mod_sysfs_setup(struct module *mod,
1709                           const struct load_info *info,
1710                           struct kernel_param *kparam,
1711                           unsigned int num_params)
1712{
1713        return 0;
1714}
1715
1716static void mod_sysfs_fini(struct module *mod)
1717{
1718}
1719
1720static void module_remove_modinfo_attrs(struct module *mod)
1721{
1722}
1723
1724static void del_usage_links(struct module *mod)
1725{
1726}
1727
1728#endif /* CONFIG_SYSFS */
1729
1730static void mod_sysfs_teardown(struct module *mod)
1731{
1732        del_usage_links(mod);
1733        module_remove_modinfo_attrs(mod);
1734        module_param_sysfs_remove(mod);
1735        kobject_put(mod->mkobj.drivers_dir);
1736        kobject_put(mod->holders_dir);
1737        mod_sysfs_fini(mod);
1738}
1739
1740/*
1741 * unlink the module with the whole machine is stopped with interrupts off
1742 * - this defends against kallsyms not taking locks
1743 */
1744static int __unlink_module(void *_mod)
1745{
1746        struct module *mod = _mod;
1747        list_del(&mod->list);
1748        module_bug_cleanup(mod);
1749        return 0;
1750}
1751
1752#ifdef CONFIG_DEBUG_SET_MODULE_RONX
1753/*
1754 * LKM RO/NX protection: protect module's text/ro-data
1755 * from modification and any data from execution.
1756 */
1757void set_page_attributes(void *start, void *end, int (*set)(unsigned long start, int num_pages))
1758{
1759        unsigned long begin_pfn = PFN_DOWN((unsigned long)start);
1760        unsigned long end_pfn = PFN_DOWN((unsigned long)end);
1761
1762        if (end_pfn > begin_pfn)
1763                set(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1764}
1765
1766static void set_section_ro_nx(void *base,
1767                        unsigned long text_size,
1768                        unsigned long ro_size,
1769                        unsigned long total_size)
1770{
1771        /* begin and end PFNs of the current subsection */
1772        unsigned long begin_pfn;
1773        unsigned long end_pfn;
1774
1775        /*
1776         * Set RO for module text and RO-data:
1777         * - Always protect first page.
1778         * - Do not protect last partial page.
1779         */
1780        if (ro_size > 0)
1781                set_page_attributes(base, base + ro_size, set_memory_ro);
1782
1783        /*
1784         * Set NX permissions for module data:
1785         * - Do not protect first partial page.
1786         * - Always protect last page.
1787         */
1788        if (total_size > text_size) {
1789                begin_pfn = PFN_UP((unsigned long)base + text_size);
1790                end_pfn = PFN_UP((unsigned long)base + total_size);
1791                if (end_pfn > begin_pfn)
1792                        set_memory_nx(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1793        }
1794}
1795
1796static void unset_module_core_ro_nx(struct module *mod)
1797{
1798        set_page_attributes(mod->module_core + mod->core_text_size,
1799                mod->module_core + mod->core_size,
1800                set_memory_x);
1801        set_page_attributes(mod->module_core,
1802                mod->module_core + mod->core_ro_size,
1803                set_memory_rw);
1804}
1805
1806static void unset_module_init_ro_nx(struct module *mod)
1807{
1808        set_page_attributes(mod->module_init + mod->init_text_size,
1809                mod->module_init + mod->init_size,
1810                set_memory_x);
1811        set_page_attributes(mod->module_init,
1812                mod->module_init + mod->init_ro_size,
1813                set_memory_rw);
1814}
1815
1816/* Iterate through all modules and set each module's text as RW */
1817void set_all_modules_text_rw(void)
1818{
1819        struct module *mod;
1820
1821        mutex_lock(&module_mutex);
1822        list_for_each_entry_rcu(mod, &modules, list) {
1823                if (mod->state == MODULE_STATE_UNFORMED)
1824                        continue;
1825                if ((mod->module_core) && (mod->core_text_size)) {
1826                        set_page_attributes(mod->module_core,
1827                                                mod->module_core + mod->core_text_size,
1828                                                set_memory_rw);
1829                }
1830                if ((mod->module_init) && (mod->init_text_size)) {
1831                        set_page_attributes(mod->module_init,
1832                                                mod->module_init + mod->init_text_size,
1833                                                set_memory_rw);
1834                }
1835        }
1836        mutex_unlock(&module_mutex);
1837}
1838
1839/* Iterate through all modules and set each module's text as RO */
1840void set_all_modules_text_ro(void)
1841{
1842        struct module *mod;
1843
1844        mutex_lock(&module_mutex);
1845        list_for_each_entry_rcu(mod, &modules, list) {
1846                if (mod->state == MODULE_STATE_UNFORMED)
1847                        continue;
1848                if ((mod->module_core) && (mod->core_text_size)) {
1849                        set_page_attributes(mod->module_core,
1850                                                mod->module_core + mod->core_text_size,
1851                                                set_memory_ro);
1852                }
1853                if ((mod->module_init) && (mod->init_text_size)) {
1854                        set_page_attributes(mod->module_init,
1855                                                mod->module_init + mod->init_text_size,
1856                                                set_memory_ro);
1857                }
1858        }
1859        mutex_unlock(&module_mutex);
1860}
1861#else
1862static inline void set_section_ro_nx(void *base, unsigned long text_size, unsigned long ro_size, unsigned long total_size) { }
1863static void unset_module_core_ro_nx(struct module *mod) { }
1864static void unset_module_init_ro_nx(struct module *mod) { }
1865#endif
1866
1867void __weak module_free(struct module *mod, void *module_region)
1868{
1869        vfree(module_region);
1870}
1871
1872void __weak module_arch_cleanup(struct module *mod)
1873{
1874}
1875
1876/* Free a module, remove from lists, etc. */
1877static void free_module(struct module *mod)
1878{
1879        trace_module_free(mod);
1880
1881        mod_sysfs_teardown(mod);
1882
1883        /* We leave it in list to prevent duplicate loads, but make sure
1884         * that noone uses it while it's being deconstructed. */
1885        mod->state = MODULE_STATE_UNFORMED;
1886
1887        /* Remove dynamic debug info */
1888        ddebug_remove_module(mod->name);
1889
1890        /* Arch-specific cleanup. */
1891        module_arch_cleanup(mod);
1892
1893        /* Module unload stuff */
1894        module_unload_free(mod);
1895
1896        /* Free any allocated parameters. */
1897        destroy_params(mod->kp, mod->num_kp);
1898
1899        /* Now we can delete it from the lists */
1900        mutex_lock(&module_mutex);
1901        stop_machine(__unlink_module, mod, NULL);
1902        mutex_unlock(&module_mutex);
1903
1904        /* This may be NULL, but that's OK */
1905        unset_module_init_ro_nx(mod);
1906        module_free(mod, mod->module_init);
1907        kfree(mod->args);
1908        percpu_modfree(mod);
1909
1910        /* Free lock-classes: */
1911        lockdep_free_key_range(mod->module_core, mod->core_size);
1912
1913        /* Finally, free the core (containing the module structure) */
1914        unset_module_core_ro_nx(mod);
1915        module_free(mod, mod->module_core);
1916
1917#ifdef CONFIG_MPU
1918        update_protections(current->mm);
1919#endif
1920}
1921
1922void *__symbol_get(const char *symbol)
1923{
1924        struct module *owner;
1925        const struct kernel_symbol *sym;
1926
1927        preempt_disable();
1928        sym = find_symbol(symbol, &owner, NULL, true, true);
1929        if (sym && strong_try_module_get(owner))
1930                sym = NULL;
1931        preempt_enable();
1932
1933        return sym ? (void *)sym->value : NULL;
1934}
1935EXPORT_SYMBOL_GPL(__symbol_get);
1936
1937/*
1938 * Ensure that an exported symbol [global namespace] does not already exist
1939 * in the kernel or in some other module's exported symbol table.
1940 *
1941 * You must hold the module_mutex.
1942 */
1943static int verify_export_symbols(struct module *mod)
1944{
1945        unsigned int i;
1946        struct module *owner;
1947        const struct kernel_symbol *s;
1948        struct {
1949                const struct kernel_symbol *sym;
1950                unsigned int num;
1951        } arr[] = {
1952                { mod->syms, mod->num_syms },
1953                { mod->gpl_syms, mod->num_gpl_syms },
1954                { mod->gpl_future_syms, mod->num_gpl_future_syms },
1955#ifdef CONFIG_UNUSED_SYMBOLS
1956                { mod->unused_syms, mod->num_unused_syms },
1957                { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1958#endif
1959        };
1960
1961        for (i = 0; i < ARRAY_SIZE(arr); i++) {
1962                for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1963                        if (find_symbol(s->name, &owner, NULL, true, false)) {
1964                                printk(KERN_ERR
1965                                       "%s: exports duplicate symbol %s"
1966                                       " (owned by %s)\n",
1967                                       mod->name, s->name, module_name(owner));
1968                                return -ENOEXEC;
1969                        }
1970                }
1971        }
1972        return 0;
1973}
1974
1975/* Change all symbols so that st_value encodes the pointer directly. */
1976static int simplify_symbols(struct module *mod, const struct load_info *info)
1977{
1978        Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
1979        Elf_Sym *sym = (void *)symsec->sh_addr;
1980        unsigned long secbase;
1981        unsigned int i;
1982        int ret = 0;
1983        const struct kernel_symbol *ksym;
1984
1985        for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
1986                const char *name = info->strtab + sym[i].st_name;
1987
1988                switch (sym[i].st_shndx) {
1989                case SHN_COMMON:
1990                        /* We compiled with -fno-common.  These are not
1991                           supposed to happen.  */
1992                        pr_debug("Common symbol: %s\n", name);
1993                        printk("%s: please compile with -fno-common\n",
1994                               mod->name);
1995                        ret = -ENOEXEC;
1996                        break;
1997
1998                case SHN_ABS:
1999                        /* Don't need to do anything */
2000                        pr_debug("Absolute symbol: 0x%08lx\n",
2001                               (long)sym[i].st_value);
2002                        break;
2003
2004                case SHN_UNDEF:
2005                        ksym = resolve_symbol_wait(mod, info, name);
2006                        /* Ok if resolved.  */
2007                        if (ksym && !IS_ERR(ksym)) {
2008                                sym[i].st_value = ksym->value;
2009                                break;
2010                        }
2011
2012                        /* Ok if weak.  */
2013                        if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
2014                                break;
2015
2016                        printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
2017                               mod->name, name, PTR_ERR(ksym));
2018                        ret = PTR_ERR(ksym) ?: -ENOENT;
2019                        break;
2020
2021                default:
2022                        /* Divert to percpu allocation if a percpu var. */
2023                        if (sym[i].st_shndx == info->index.pcpu)
2024                                secbase = (unsigned long)mod_percpu(mod);
2025                        else
2026                                secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
2027                        sym[i].st_value += secbase;
2028                        break;
2029                }
2030        }
2031
2032        return ret;
2033}
2034
2035static int apply_relocations(struct module *mod, const struct load_info *info)
2036{
2037        unsigned int i;
2038        int err = 0;
2039
2040        /* Now do relocations. */
2041        for (i = 1; i < info->hdr->e_shnum; i++) {
2042                unsigned int infosec = info->sechdrs[i].sh_info;
2043
2044                /* Not a valid relocation section? */
2045                if (infosec >= info->hdr->e_shnum)
2046                        continue;
2047
2048                /* Don't bother with non-allocated sections */
2049                if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
2050                        continue;
2051
2052                if (info->sechdrs[i].sh_type == SHT_REL)
2053                        err = apply_relocate(info->sechdrs, info->strtab,
2054                                             info->index.sym, i, mod);
2055                else if (info->sechdrs[i].sh_type == SHT_RELA)
2056                        err = apply_relocate_add(info->sechdrs, info->strtab,
2057                                                 info->index.sym, i, mod);
2058                if (err < 0)
2059                        break;
2060        }
2061        return err;
2062}
2063
2064/* Additional bytes needed by arch in front of individual sections */
2065unsigned int __weak arch_mod_section_prepend(struct module *mod,
2066                                             unsigned int section)
2067{
2068        /* default implementation just returns zero */
2069        return 0;
2070}
2071
2072/* Update size with this section: return offset. */
2073static long get_offset(struct module *mod, unsigned int *size,
2074                       Elf_Shdr *sechdr, unsigned int section)
2075{
2076        long ret;
2077
2078        *size += arch_mod_section_prepend(mod, section);
2079        ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2080        *size = ret + sechdr->sh_size;
2081        return ret;
2082}
2083
2084/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2085   might -- code, read-only data, read-write data, small data.  Tally
2086   sizes, and place the offsets into sh_entsize fields: high bit means it
2087   belongs in init. */
2088static void layout_sections(struct module *mod, struct load_info *info)
2089{
2090        static unsigned long const masks[][2] = {
2091                /* NOTE: all executable code must be the first section
2092                 * in this array; otherwise modify the text_size
2093                 * finder in the two loops below */
2094                { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2095                { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
2096                { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2097                { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2098        };
2099        unsigned int m, i;
2100
2101        for (i = 0; i < info->hdr->e_shnum; i++)
2102                info->sechdrs[i].sh_entsize = ~0UL;
2103
2104        pr_debug("Core section allocation order:\n");
2105        for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2106                for (i = 0; i < info->hdr->e_shnum; ++i) {
2107                        Elf_Shdr *s = &info->sechdrs[i];
2108                        const char *sname = info->secstrings + s->sh_name;
2109
2110                        if ((s->sh_flags & masks[m][0]) != masks[m][0]
2111                            || (s->sh_flags & masks[m][1])
2112                            || s->sh_entsize != ~0UL
2113                            || strstarts(sname, ".init"))
2114                                continue;
2115                        s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
2116                        pr_debug("\t%s\n", sname);
2117                }
2118                switch (m) {
2119                case 0: /* executable */
2120                        mod->core_size = debug_align(mod->core_size);
2121                        mod->core_text_size = mod->core_size;
2122                        break;
2123                case 1: /* RO: text and ro-data */
2124                        mod->core_size = debug_align(mod->core_size);
2125                        mod->core_ro_size = mod->core_size;
2126                        break;
2127                case 3: /* whole core */
2128                        mod->core_size = debug_align(mod->core_size);
2129                        break;
2130                }
2131        }
2132
2133        pr_debug("Init section allocation order:\n");
2134        for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2135                for (i = 0; i < info->hdr->e_shnum; ++i) {
2136                        Elf_Shdr *s = &info->sechdrs[i];
2137                        const char *sname = info->secstrings + s->sh_name;
2138
2139                        if ((s->sh_flags & masks[m][0]) != masks[m][0]
2140                            || (s->sh_flags & masks[m][1])
2141                            || s->sh_entsize != ~0UL
2142                            || !strstarts(sname, ".init"))
2143                                continue;
2144                        s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
2145                                         | INIT_OFFSET_MASK);
2146                        pr_debug("\t%s\n", sname);
2147                }
2148                switch (m) {
2149                case 0: /* executable */
2150                        mod->init_size = debug_align(mod->init_size);
2151                        mod->init_text_size = mod->init_size;
2152                        break;
2153                case 1: /* RO: text and ro-data */
2154                        mod->init_size = debug_align(mod->init_size);
2155                        mod->init_ro_size = mod->init_size;
2156                        break;
2157                case 3: /* whole init */
2158                        mod->init_size = debug_align(mod->init_size);
2159                        break;
2160                }
2161        }
2162}
2163
2164static void set_license(struct module *mod, const char *license)
2165{
2166        if (!license)
2167                license = "unspecified";
2168
2169        if (!license_is_gpl_compatible(license)) {
2170                if (!test_taint(TAINT_PROPRIETARY_MODULE))
2171                        printk(KERN_WARNING "%s: module license '%s' taints "
2172                                "kernel.\n", mod->name, license);
2173                add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2174                                 LOCKDEP_NOW_UNRELIABLE);
2175        }
2176}
2177
2178/* Parse tag=value strings from .modinfo section */
2179static char *next_string(char *string, unsigned long *secsize)
2180{
2181        /* Skip non-zero chars */
2182        while (string[0]) {
2183                string++;
2184                if ((*secsize)-- <= 1)
2185                        return NULL;
2186        }
2187
2188        /* Skip any zero padding. */
2189        while (!string[0]) {
2190                string++;
2191                if ((*secsize)-- <= 1)
2192                        return NULL;
2193        }
2194        return string;
2195}
2196
2197static char *get_modinfo(struct load_info *info, const char *tag)
2198{
2199        char *p;
2200        unsigned int taglen = strlen(tag);
2201        Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2202        unsigned long size = infosec->sh_size;
2203
2204        for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
2205                if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2206                        return p + taglen + 1;
2207        }
2208        return NULL;
2209}
2210
2211static void setup_modinfo(struct module *mod, struct load_info *info)
2212{
2213        struct module_attribute *attr;
2214        int i;
2215
2216        for (i = 0; (attr = modinfo_attrs[i]); i++) {
2217                if (attr->setup)
2218                        attr->setup(mod, get_modinfo(info, attr->attr.name));
2219        }
2220}
2221
2222static void free_modinfo(struct module *mod)
2223{
2224        struct module_attribute *attr;
2225        int i;
2226
2227        for (i = 0; (attr = modinfo_attrs[i]); i++) {
2228                if (attr->free)
2229                        attr->free(mod);
2230        }
2231}
2232
2233#ifdef CONFIG_KALLSYMS
2234
2235/* lookup symbol in given range of kernel_symbols */
2236static const struct kernel_symbol *lookup_symbol(const char *name,
2237        const struct kernel_symbol *start,
2238        const struct kernel_symbol *stop)
2239{
2240        return bsearch(name, start, stop - start,
2241                        sizeof(struct kernel_symbol), cmp_name);
2242}
2243
2244static int is_exported(const char *name, unsigned long value,
2245                       const struct module *mod)
2246{
2247        const struct kernel_symbol *ks;
2248        if (!mod)
2249                ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
2250        else
2251                ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
2252        return ks != NULL && ks->value == value;
2253}
2254
2255/* As per nm */
2256static char elf_type(const Elf_Sym *sym, const struct load_info *info)
2257{
2258        const Elf_Shdr *sechdrs = info->sechdrs;
2259
2260        if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2261                if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2262                        return 'v';
2263                else
2264                        return 'w';
2265        }
2266        if (sym->st_shndx == SHN_UNDEF)
2267                return 'U';
2268        if (sym->st_shndx == SHN_ABS)
2269                return 'a';
2270        if (sym->st_shndx >= SHN_LORESERVE)
2271                return '?';
2272        if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2273                return 't';
2274        if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2275            && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2276                if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2277                        return 'r';
2278                else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2279                        return 'g';
2280                else
2281                        return 'd';
2282        }
2283        if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2284                if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2285                        return 's';
2286                else
2287                        return 'b';
2288        }
2289        if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2290                      ".debug")) {
2291                return 'n';
2292        }
2293        return '?';
2294}
2295
2296static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
2297                           unsigned int shnum)
2298{
2299        const Elf_Shdr *sec;
2300
2301        if (src->st_shndx == SHN_UNDEF
2302            || src->st_shndx >= shnum
2303            || !src->st_name)
2304                return false;
2305
2306        sec = sechdrs + src->st_shndx;
2307        if (!(sec->sh_flags & SHF_ALLOC)
2308#ifndef CONFIG_KALLSYMS_ALL
2309            || !(sec->sh_flags & SHF_EXECINSTR)
2310#endif
2311            || (sec->sh_entsize & INIT_OFFSET_MASK))
2312                return false;
2313
2314        return true;
2315}
2316
2317/*
2318 * We only allocate and copy the strings needed by the parts of symtab
2319 * we keep.  This is simple, but has the effect of making multiple
2320 * copies of duplicates.  We could be more sophisticated, see
2321 * linux-kernel thread starting with
2322 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2323 */
2324static void layout_symtab(struct module *mod, struct load_info *info)
2325{
2326        Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2327        Elf_Shdr *strsect = info->sechdrs + info->index.str;
2328        const Elf_Sym *src;
2329        unsigned int i, nsrc, ndst, strtab_size = 0;
2330
2331        /* Put symbol section at end of init part of module. */
2332        symsect->sh_flags |= SHF_ALLOC;
2333        symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
2334                                         info->index.sym) | INIT_OFFSET_MASK;
2335        pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
2336
2337        src = (void *)info->hdr + symsect->sh_offset;
2338        nsrc = symsect->sh_size / sizeof(*src);
2339
2340        /* Compute total space required for the core symbols' strtab. */
2341        for (ndst = i = 0; i < nsrc; i++) {
2342                if (i == 0 ||
2343                    is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2344                        strtab_size += strlen(&info->strtab[src[i].st_name])+1;
2345                        ndst++;
2346                }
2347        }
2348
2349        /* Append room for core symbols at end of core part. */
2350        info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
2351        info->stroffs = mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym);
2352        mod->core_size += strtab_size;
2353
2354        /* Put string table section at end of init part of module. */
2355        strsect->sh_flags |= SHF_ALLOC;
2356        strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
2357                                         info->index.str) | INIT_OFFSET_MASK;
2358        pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
2359}
2360
2361static void add_kallsyms(struct module *mod, const struct load_info *info)
2362{
2363        unsigned int i, ndst;
2364        const Elf_Sym *src;
2365        Elf_Sym *dst;
2366        char *s;
2367        Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2368
2369        mod->symtab = (void *)symsec->sh_addr;
2370        mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2371        /* Make sure we get permanent strtab: don't use info->strtab. */
2372        mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2373
2374        /* Set types up while we still have access to sections. */
2375        for (i = 0; i < mod->num_symtab; i++)
2376                mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
2377
2378        mod->core_symtab = dst = mod->module_core + info->symoffs;
2379        mod->core_strtab = s = mod->module_core + info->stroffs;
2380        src = mod->symtab;
2381        for (ndst = i = 0; i < mod->num_symtab; i++) {
2382                if (i == 0 ||
2383                    is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2384                        dst[ndst] = src[i];
2385                        dst[ndst++].st_name = s - mod->core_strtab;
2386                        s += strlcpy(s, &mod->strtab[src[i].st_name],
2387                                     KSYM_NAME_LEN) + 1;
2388                }
2389        }
2390        mod->core_num_syms = ndst;
2391}
2392#else
2393static inline void layout_symtab(struct module *mod, struct load_info *info)
2394{
2395}
2396
2397static void add_kallsyms(struct module *mod, const struct load_info *info)
2398{
2399}
2400#endif /* CONFIG_KALLSYMS */
2401
2402static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2403{
2404        if (!debug)
2405                return;
2406#ifdef CONFIG_DYNAMIC_DEBUG
2407        if (ddebug_add_module(debug, num, debug->modname))
2408                printk(KERN_ERR "dynamic debug error adding module: %s\n",
2409                                        debug->modname);
2410#endif
2411}
2412
2413static void dynamic_debug_remove(struct _ddebug *debug)
2414{
2415        if (debug)
2416                ddebug_remove_module(debug->modname);
2417}
2418
2419void * __weak module_alloc(unsigned long size)
2420{
2421        return vmalloc_exec(size);
2422}
2423
2424static void *module_alloc_update_bounds(unsigned long size)
2425{
2426        void *ret = module_alloc(size);
2427
2428        if (ret) {
2429                mutex_lock(&module_mutex);
2430                /* Update module bounds. */
2431                if ((unsigned long)ret < module_addr_min)
2432                        module_addr_min = (unsigned long)ret;
2433                if ((unsigned long)ret + size > module_addr_max)
2434                        module_addr_max = (unsigned long)ret + size;
2435                mutex_unlock(&module_mutex);
2436        }
2437        return ret;
2438}
2439
2440#ifdef CONFIG_DEBUG_KMEMLEAK
2441static void kmemleak_load_module(const struct module *mod,
2442                                 const struct load_info *info)
2443{
2444        unsigned int i;
2445
2446        /* only scan the sections containing data */
2447        kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2448
2449        for (i = 1; i < info->hdr->e_shnum; i++) {
2450                /* Scan all writable sections that's not executable */
2451                if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
2452                    !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
2453                    (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
2454                        continue;
2455
2456                kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2457                                   info->sechdrs[i].sh_size, GFP_KERNEL);
2458        }
2459}
2460#else
2461static inline void kmemleak_load_module(const struct module *mod,
2462                                        const struct load_info *info)
2463{
2464}
2465#endif
2466
2467#ifdef CONFIG_MODULE_SIG
2468static int module_sig_check(struct load_info *info)
2469{
2470        int err = -ENOKEY;
2471        const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2472        const void *mod = info->hdr;
2473
2474        if (info->len > markerlen &&
2475            memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
2476                /* We truncate the module to discard the signature */
2477                info->len -= markerlen;
2478                err = mod_verify_sig(mod, &info->len);
2479        }
2480
2481        if (!err) {
2482                info->sig_ok = true;
2483                return 0;
2484        }
2485
2486        /* Not having a signature is only an error if we're strict. */
2487        if (err < 0 && fips_enabled)
2488                panic("Module verification failed with error %d in FIPS mode\n",
2489                      err);
2490        if (err == -ENOKEY && !sig_enforce)
2491                err = 0;
2492
2493        return err;
2494}
2495#else /* !CONFIG_MODULE_SIG */
2496static int module_sig_check(struct load_info *info)
2497{
2498        return 0;
2499}
2500#endif /* !CONFIG_MODULE_SIG */
2501
2502/* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2503static int elf_header_check(struct load_info *info)
2504{
2505        if (info->len < sizeof(*(info->hdr)))
2506                return -ENOEXEC;
2507
2508        if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2509            || info->hdr->e_type != ET_REL
2510            || !elf_check_arch(info->hdr)
2511            || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2512                return -ENOEXEC;
2513
2514        if (info->hdr->e_shoff >= info->len
2515            || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2516                info->len - info->hdr->e_shoff))
2517                return -ENOEXEC;
2518
2519        return 0;
2520}
2521
2522/* Sets info->hdr and info->len. */
2523static int copy_module_from_user(const void __user *umod, unsigned long len,
2524                                  struct load_info *info)
2525{
2526        int err;
2527
2528        info->len = len;
2529        if (info->len < sizeof(*(info->hdr)))
2530                return -ENOEXEC;
2531
2532        err = security_kernel_module_from_file(NULL);
2533        if (err)
2534                return err;
2535
2536        /* Suck in entire file: we'll want most of it. */
2537        info->hdr = vmalloc(info->len);
2538        if (!info->hdr)
2539                return -ENOMEM;
2540
2541        if (copy_from_user(info->hdr, umod, info->len) != 0) {
2542                vfree(info->hdr);
2543                return -EFAULT;
2544        }
2545
2546        return 0;
2547}
2548
2549/* Sets info->hdr and info->len. */
2550static int copy_module_from_fd(int fd, struct load_info *info)
2551{
2552        struct fd f = fdget(fd);
2553        int err;
2554        struct kstat stat;
2555        loff_t pos;
2556        ssize_t bytes = 0;
2557
2558        if (!f.file)
2559                return -ENOEXEC;
2560
2561        err = security_kernel_module_from_file(f.file);
2562        if (err)
2563                goto out;
2564
2565        err = vfs_getattr(&f.file->f_path, &stat);
2566        if (err)
2567                goto out;
2568
2569        if (stat.size > INT_MAX) {
2570                err = -EFBIG;
2571                goto out;
2572        }
2573
2574        /* Don't hand 0 to vmalloc, it whines. */
2575        if (stat.size == 0) {
2576                err = -EINVAL;
2577                goto out;
2578        }
2579
2580        info->hdr = vmalloc(stat.size);
2581        if (!info->hdr) {
2582                err = -ENOMEM;
2583                goto out;
2584        }
2585
2586        pos = 0;
2587        while (pos < stat.size) {
2588                bytes = kernel_read(f.file, pos, (char *)(info->hdr) + pos,
2589                                    stat.size - pos);
2590                if (bytes < 0) {
2591                        vfree(info->hdr);
2592                        err = bytes;
2593                        goto out;
2594                }
2595                if (bytes == 0)
2596                        break;
2597                pos += bytes;
2598        }
2599        info->len = pos;
2600
2601out:
2602        fdput(f);
2603        return err;
2604}
2605
2606static void free_copy(struct load_info *info)
2607{
2608        vfree(info->hdr);
2609}
2610
2611static int rewrite_section_headers(struct load_info *info, int flags)
2612{
2613        unsigned int i;
2614
2615        /* This should always be true, but let's be sure. */
2616        info->sechdrs[0].sh_addr = 0;
2617
2618        for (i = 1; i < info->hdr->e_shnum; i++) {
2619                Elf_Shdr *shdr = &info->sechdrs[i];
2620                if (shdr->sh_type != SHT_NOBITS
2621                    && info->len < shdr->sh_offset + shdr->sh_size) {
2622                        printk(KERN_ERR "Module len %lu truncated\n",
2623                               info->len);
2624                        return -ENOEXEC;
2625                }
2626
2627                /* Mark all sections sh_addr with their address in the
2628                   temporary image. */
2629                shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2630
2631#ifndef CONFIG_MODULE_UNLOAD
2632                /* Don't load .exit sections */
2633                if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2634                        shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2635#endif
2636        }
2637
2638        /* Track but don't keep modinfo and version sections. */
2639        if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
2640                info->index.vers = 0; /* Pretend no __versions section! */
2641        else
2642                info->index.vers = find_sec(info, "__versions");
2643        info->index.info = find_sec(info, ".modinfo");
2644        info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2645        info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2646        return 0;
2647}
2648
2649/*
2650 * Set up our basic convenience variables (pointers to section headers,
2651 * search for module section index etc), and do some basic section
2652 * verification.
2653 *
2654 * Return the temporary module pointer (we'll replace it with the final
2655 * one when we move the module sections around).
2656 */
2657static struct module *setup_load_info(struct load_info *info, int flags)
2658{
2659        unsigned int i;
2660        int err;
2661        struct module *mod;
2662
2663        /* Set up the convenience variables */
2664        info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2665        info->secstrings = (void *)info->hdr
2666                + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2667
2668        err = rewrite_section_headers(info, flags);
2669        if (err)
2670                return ERR_PTR(err);
2671
2672        /* Find internal symbols and strings. */
2673        for (i = 1; i < info->hdr->e_shnum; i++) {
2674                if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2675                        info->index.sym = i;
2676                        info->index.str = info->sechdrs[i].sh_link;
2677                        info->strtab = (char *)info->hdr
2678                                + info->sechdrs[info->index.str].sh_offset;
2679                        break;
2680                }
2681        }
2682
2683        info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
2684        if (!info->index.mod) {
2685                printk(KERN_WARNING "No module found in object\n");
2686                return ERR_PTR(-ENOEXEC);
2687        }
2688        /* This is temporary: point mod into copy of data. */
2689        mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2690
2691        if (info->index.sym == 0) {
2692                printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2693                       mod->name);
2694                return ERR_PTR(-ENOEXEC);
2695        }
2696
2697        info->index.pcpu = find_pcpusec(info);
2698
2699        /* Check module struct version now, before we try to use module. */
2700        if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2701                return ERR_PTR(-ENOEXEC);
2702
2703        return mod;
2704}
2705
2706static int check_modinfo(struct module *mod, struct load_info *info, int flags)
2707{
2708        const char *modmagic = get_modinfo(info, "vermagic");
2709        int err;
2710
2711        if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2712                modmagic = NULL;
2713
2714        /* This is allowed: modprobe --force will invalidate it. */
2715        if (!modmagic) {
2716                err = try_to_force_load(mod, "bad vermagic");
2717                if (err)
2718                        return err;
2719        } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2720                printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2721                       mod->name, modmagic, vermagic);
2722                return -ENOEXEC;
2723        }
2724
2725        if (!get_modinfo(info, "intree"))
2726                add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
2727
2728        if (get_modinfo(info, "staging")) {
2729                add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
2730                printk(KERN_WARNING "%s: module is from the staging directory,"
2731                       " the quality is unknown, you have been warned.\n",
2732                       mod->name);
2733        }
2734
2735        /* Set up license info based on the info section */
2736        set_license(mod, get_modinfo(info, "license"));
2737
2738        return 0;
2739}
2740
2741static void find_module_sections(struct module *mod, struct load_info *info)
2742{
2743        mod->kp = section_objs(info, "__param",
2744                               sizeof(*mod->kp), &mod->num_kp);
2745        mod->syms = section_objs(info, "__ksymtab",
2746                                 sizeof(*mod->syms), &mod->num_syms);
2747        mod->crcs = section_addr(info, "__kcrctab");
2748        mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2749                                     sizeof(*mod->gpl_syms),
2750                                     &mod->num_gpl_syms);
2751        mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2752        mod->gpl_future_syms = section_objs(info,
2753                                            "__ksymtab_gpl_future",
2754                                            sizeof(*mod->gpl_future_syms),
2755                                            &mod->num_gpl_future_syms);
2756        mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
2757
2758#ifdef CONFIG_UNUSED_SYMBOLS
2759        mod->unused_syms = section_objs(info, "__ksymtab_unused",
2760                                        sizeof(*mod->unused_syms),
2761                                        &mod->num_unused_syms);
2762        mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2763        mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
2764                                            sizeof(*mod->unused_gpl_syms),
2765                                            &mod->num_unused_gpl_syms);
2766        mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
2767#endif
2768#ifdef CONFIG_CONSTRUCTORS
2769        mod->ctors = section_objs(info, ".ctors",
2770                                  sizeof(*mod->ctors), &mod->num_ctors);
2771#endif
2772
2773#ifdef CONFIG_TRACEPOINTS
2774        mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2775                                             sizeof(*mod->tracepoints_ptrs),
2776                                             &mod->num_tracepoints);
2777#endif
2778#ifdef HAVE_JUMP_LABEL
2779        mod->jump_entries = section_objs(info, "__jump_table",
2780                                        sizeof(*mod->jump_entries),
2781                                        &mod->num_jump_entries);
2782#endif
2783#ifdef CONFIG_EVENT_TRACING
2784        mod->trace_events = section_objs(info, "_ftrace_events",
2785                                         sizeof(*mod->trace_events),
2786                                         &mod->num_trace_events);
2787#endif
2788#ifdef CONFIG_TRACING
2789        mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2790                                         sizeof(*mod->trace_bprintk_fmt_start),
2791                                         &mod->num_trace_bprintk_fmt);
2792#endif
2793#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2794        /* sechdrs[0].sh_size is always zero */
2795        mod->ftrace_callsites = section_objs(info, "__mcount_loc",
2796                                             sizeof(*mod->ftrace_callsites),
2797                                             &mod->num_ftrace_callsites);
2798#endif
2799
2800        mod->extable = section_objs(info, "__ex_table",
2801                                    sizeof(*mod->extable), &mod->num_exentries);
2802
2803        if (section_addr(info, "__obsparm"))
2804                printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2805                       mod->name);
2806
2807        info->debug = section_objs(info, "__verbose",
2808                                   sizeof(*info->debug), &info->num_debug);
2809}
2810
2811static int move_module(struct module *mod, struct load_info *info)
2812{
2813        int i;
2814        void *ptr;
2815
2816        /* Do the allocs. */
2817        ptr = module_alloc_update_bounds(mod->core_size);
2818        /*
2819         * The pointer to this block is stored in the module structure
2820         * which is inside the block. Just mark it as not being a
2821         * leak.
2822         */
2823        kmemleak_not_leak(ptr);
2824        if (!ptr)
2825                return -ENOMEM;
2826
2827        memset(ptr, 0, mod->core_size);
2828        mod->module_core = ptr;
2829
2830        if (mod->init_size) {
2831                ptr = module_alloc_update_bounds(mod->init_size);
2832                /*
2833                 * The pointer to this block is stored in the module structure
2834                 * which is inside the block. This block doesn't need to be
2835                 * scanned as it contains data and code that will be freed
2836                 * after the module is initialized.
2837                 */
2838                kmemleak_ignore(ptr);
2839                if (!ptr) {
2840                        module_free(mod, mod->module_core);
2841                        return -ENOMEM;
2842                }
2843                memset(ptr, 0, mod->init_size);
2844                mod->module_init = ptr;
2845        } else
2846                mod->module_init = NULL;
2847
2848        /* Transfer each section which specifies SHF_ALLOC */
2849        pr_debug("final section addresses:\n");
2850        for (i = 0; i < info->hdr->e_shnum; i++) {
2851                void *dest;
2852                Elf_Shdr *shdr = &info->sechdrs[i];
2853
2854                if (!(shdr->sh_flags & SHF_ALLOC))
2855                        continue;
2856
2857                if (shdr->sh_entsize & INIT_OFFSET_MASK)
2858                        dest = mod->module_init
2859                                + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
2860                else
2861                        dest = mod->module_core + shdr->sh_entsize;
2862
2863                if (shdr->sh_type != SHT_NOBITS)
2864                        memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2865                /* Update sh_addr to point to copy in image. */
2866                shdr->sh_addr = (unsigned long)dest;
2867                pr_debug("\t0x%lx %s\n",
2868                         (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
2869        }
2870
2871        return 0;
2872}
2873
2874static int check_module_license_and_versions(struct module *mod)
2875{
2876        /*
2877         * ndiswrapper is under GPL by itself, but loads proprietary modules.
2878         * Don't use add_taint_module(), as it would prevent ndiswrapper from
2879         * using GPL-only symbols it needs.
2880         */
2881        if (strcmp(mod->name, "ndiswrapper") == 0)
2882                add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
2883
2884        /* driverloader was caught wrongly pretending to be under GPL */
2885        if (strcmp(mod->name, "driverloader") == 0)
2886                add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2887                                 LOCKDEP_NOW_UNRELIABLE);
2888
2889        /* lve claims to be GPL but upstream won't provide source */
2890        if (strcmp(mod->name, "lve") == 0)
2891                add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2892                                 LOCKDEP_NOW_UNRELIABLE);
2893
2894#ifdef CONFIG_MODVERSIONS
2895        if ((mod->num_syms && !mod->crcs)
2896            || (mod->num_gpl_syms && !mod->gpl_crcs)
2897            || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2898#ifdef CONFIG_UNUSED_SYMBOLS
2899            || (mod->num_unused_syms && !mod->unused_crcs)
2900            || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2901#endif
2902                ) {
2903                return try_to_force_load(mod,
2904                                         "no versions for exported symbols");
2905        }
2906#endif
2907        return 0;
2908}
2909
2910static void flush_module_icache(const struct module *mod)
2911{
2912        mm_segment_t old_fs;
2913
2914        /* flush the icache in correct context */
2915        old_fs = get_fs();
2916        set_fs(KERNEL_DS);
2917
2918        /*
2919         * Flush the instruction cache, since we've played with text.
2920         * Do it before processing of module parameters, so the module
2921         * can provide parameter accessor functions of its own.
2922         */
2923        if (mod->module_init)
2924                flush_icache_range((unsigned long)mod->module_init,
2925                                   (unsigned long)mod->module_init
2926                                   + mod->init_size);
2927        flush_icache_range((unsigned long)mod->module_core,
2928                           (unsigned long)mod->module_core + mod->core_size);
2929
2930        set_fs(old_fs);
2931}
2932
2933int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
2934                                     Elf_Shdr *sechdrs,
2935                                     char *secstrings,
2936                                     struct module *mod)
2937{
2938        return 0;
2939}
2940
2941static struct module *layout_and_allocate(struct load_info *info, int flags)
2942{
2943        /* Module within temporary copy. */
2944        struct module *mod;
2945        int err;
2946
2947        mod = setup_load_info(info, flags);
2948        if (IS_ERR(mod))
2949                return mod;
2950
2951        err = check_modinfo(mod, info, flags);
2952        if (err)
2953                return ERR_PTR(err);
2954
2955        /* Allow arches to frob section contents and sizes.  */
2956        err = module_frob_arch_sections(info->hdr, info->sechdrs,
2957                                        info->secstrings, mod);
2958        if (err < 0)
2959                return ERR_PTR(err);
2960
2961        /* We will do a special allocation for per-cpu sections later. */
2962        info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
2963
2964        /* Determine total sizes, and put offsets in sh_entsize.  For now
2965           this is done generically; there doesn't appear to be any
2966           special cases for the architectures. */
2967        layout_sections(mod, info);
2968        layout_symtab(mod, info);
2969
2970        /* Allocate and move to the final place */
2971        err = move_module(mod, info);
2972        if (err)
2973                return ERR_PTR(err);
2974
2975        /* Module has been copied to its final place now: return it. */
2976        mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2977        kmemleak_load_module(mod, info);
2978        return mod;
2979}
2980
2981/* mod is no longer valid after this! */
2982static void module_deallocate(struct module *mod, struct load_info *info)
2983{
2984        percpu_modfree(mod);
2985        module_free(mod, mod->module_init);
2986        module_free(mod, mod->module_core);
2987}
2988
2989int __weak module_finalize(const Elf_Ehdr *hdr,
2990                           const Elf_Shdr *sechdrs,
2991                           struct module *me)
2992{
2993        return 0;
2994}
2995
2996static int post_relocation(struct module *mod, const struct load_info *info)
2997{
2998        /* Sort exception table now relocations are done. */
2999        sort_extable(mod->extable, mod->extable + mod->num_exentries);
3000
3001        /* Copy relocated percpu area over. */
3002        percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
3003                       info->sechdrs[info->index.pcpu].sh_size);
3004
3005        /* Setup kallsyms-specific fields. */
3006        add_kallsyms(mod, info);
3007
3008        /* Arch-specific module finalizing. */
3009        return module_finalize(info->hdr, info->sechdrs, mod);
3010}
3011
3012/* Is this module of this name done loading?  No locks held. */
3013static bool finished_loading(const char *name)
3014{
3015        struct module *mod;
3016        bool ret;
3017
3018        mutex_lock(&module_mutex);
3019        mod = find_module_all(name, strlen(name), true);
3020        ret = !mod || mod->state == MODULE_STATE_LIVE
3021                || mod->state == MODULE_STATE_GOING;
3022        mutex_unlock(&module_mutex);
3023
3024        return ret;
3025}
3026
3027/* Call module constructors. */
3028static void do_mod_ctors(struct module *mod)
3029{
3030#ifdef CONFIG_CONSTRUCTORS
3031        unsigned long i;
3032
3033        for (i = 0; i < mod->num_ctors; i++)
3034                mod->ctors[i]();
3035#endif
3036}
3037
3038/* This is where the real work happens */
3039static int do_init_module(struct module *mod)
3040{
3041        int ret = 0;
3042
3043        /*
3044         * We want to find out whether @mod uses async during init.  Clear
3045         * PF_USED_ASYNC.  async_schedule*() will set it.
3046         */
3047        current->flags &= ~PF_USED_ASYNC;
3048
3049        blocking_notifier_call_chain(&module_notify_list,
3050                        MODULE_STATE_COMING, mod);
3051
3052        /* Set RO and NX regions for core */
3053        set_section_ro_nx(mod->module_core,
3054                                mod->core_text_size,
3055                                mod->core_ro_size,
3056                                mod->core_size);
3057
3058        /* Set RO and NX regions for init */
3059        set_section_ro_nx(mod->module_init,
3060                                mod->init_text_size,
3061                                mod->init_ro_size,
3062                                mod->init_size);
3063
3064        do_mod_ctors(mod);
3065        /* Start the module */
3066        if (mod->init != NULL)
3067                ret = do_one_initcall(mod->init);
3068        if (ret < 0) {
3069                /* Init routine failed: abort.  Try to protect us from
3070                   buggy refcounters. */
3071                mod->state = MODULE_STATE_GOING;
3072                synchronize_sched();
3073                module_put(mod);
3074                blocking_notifier_call_chain(&module_notify_list,
3075                                             MODULE_STATE_GOING, mod);
3076                free_module(mod);
3077                wake_up_all(&module_wq);
3078                return ret;
3079        }
3080        if (ret > 0) {
3081                printk(KERN_WARNING
3082"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
3083"%s: loading module anyway...\n",
3084                       __func__, mod->name, ret,
3085                       __func__);
3086                dump_stack();
3087        }
3088
3089        /* Now it's a first class citizen! */
3090        mod->state = MODULE_STATE_LIVE;
3091        blocking_notifier_call_chain(&module_notify_list,
3092                                     MODULE_STATE_LIVE, mod);
3093
3094        /*
3095         * We need to finish all async code before the module init sequence
3096         * is done.  This has potential to deadlock.  For example, a newly
3097         * detected block device can trigger request_module() of the
3098         * default iosched from async probing task.  Once userland helper
3099         * reaches here, async_synchronize_full() will wait on the async
3100         * task waiting on request_module() and deadlock.
3101         *
3102         * This deadlock is avoided by perfomring async_synchronize_full()
3103         * iff module init queued any async jobs.  This isn't a full
3104         * solution as it will deadlock the same if module loading from
3105         * async jobs nests more than once; however, due to the various
3106         * constraints, this hack seems to be the best option for now.
3107         * Please refer to the following thread for details.
3108         *
3109         * http://thread.gmane.org/gmane.linux.kernel/1420814
3110         */
3111        if (current->flags & PF_USED_ASYNC)
3112                async_synchronize_full();
3113
3114        mutex_lock(&module_mutex);
3115        /* Drop initial reference. */
3116        module_put(mod);
3117        trim_init_extable(mod);
3118#ifdef CONFIG_KALLSYMS
3119        mod->num_symtab = mod->core_num_syms;
3120        mod->symtab = mod->core_symtab;
3121        mod->strtab = mod->core_strtab;
3122#endif
3123        unset_module_init_ro_nx(mod);
3124        module_free(mod, mod->module_init);
3125        mod->module_init = NULL;
3126        mod->init_size = 0;
3127        mod->init_ro_size = 0;
3128        mod->init_text_size = 0;
3129        mutex_unlock(&module_mutex);
3130        wake_up_all(&module_wq);
3131
3132        return 0;
3133}
3134
3135static int may_init_module(void)
3136{
3137        if (!capable(CAP_SYS_MODULE) || modules_disabled)
3138                return -EPERM;
3139
3140        return 0;
3141}
3142
3143/*
3144 * We try to place it in the list now to make sure it's unique before
3145 * we dedicate too many resources.  In particular, temporary percpu
3146 * memory exhaustion.
3147 */
3148static int add_unformed_module(struct module *mod)
3149{
3150        int err;
3151        struct module *old;
3152
3153        mod->state = MODULE_STATE_UNFORMED;
3154
3155again:
3156        mutex_lock(&module_mutex);
3157        old = find_module_all(mod->name, strlen(mod->name), true);
3158        if (old != NULL) {
3159                if (old->state == MODULE_STATE_COMING
3160                    || old->state == MODULE_STATE_UNFORMED) {
3161                        /* Wait in case it fails to load. */
3162                        mutex_unlock(&module_mutex);
3163                        err = wait_event_interruptible(module_wq,
3164                                               finished_loading(mod->name));
3165                        if (err)
3166                                goto out_unlocked;
3167                        goto again;
3168                }
3169                err = -EEXIST;
3170                goto out;
3171        }
3172        list_add_rcu(&mod->list, &modules);
3173        err = 0;
3174
3175out:
3176        mutex_unlock(&module_mutex);
3177out_unlocked:
3178        return err;
3179}
3180
3181static int complete_formation(struct module *mod, struct load_info *info)
3182{
3183        int err;
3184
3185        mutex_lock(&module_mutex);
3186
3187        /* Find duplicate symbols (must be called under lock). */
3188        err = verify_export_symbols(mod);
3189        if (err < 0)
3190                goto out;
3191
3192        /* This relies on module_mutex for list integrity. */
3193        module_bug_finalize(info->hdr, info->sechdrs, mod);
3194
3195        /* Mark state as coming so strong_try_module_get() ignores us,
3196         * but kallsyms etc. can see us. */
3197        mod->state = MODULE_STATE_COMING;
3198
3199out:
3200        mutex_unlock(&module_mutex);
3201        return err;
3202}
3203
3204static int unknown_module_param_cb(char *param, char *val, const char *modname)
3205{
3206        /* Check for magic 'dyndbg' arg */ 
3207        int ret = ddebug_dyndbg_module_param_cb(param, val, modname);
3208        if (ret != 0) {
3209                printk(KERN_WARNING "%s: unknown parameter '%s' ignored\n",
3210                       modname, param);
3211        }
3212        return 0;
3213}
3214
3215/* Allocate and load the module: note that size of section 0 is always
3216   zero, and we rely on this for optional sections. */
3217static int load_module(struct load_info *info, const char __user *uargs,
3218                       int flags)
3219{
3220        struct module *mod;
3221        long err;
3222
3223        err = module_sig_check(info);
3224        if (err)
3225                goto free_copy;
3226
3227        err = elf_header_check(info);
3228        if (err)
3229                goto free_copy;
3230
3231        /* Figure out module layout, and allocate all the memory. */
3232        mod = layout_and_allocate(info, flags);
3233        if (IS_ERR(mod)) {
3234                err = PTR_ERR(mod);
3235                goto free_copy;
3236        }
3237
3238        /* Reserve our place in the list. */
3239        err = add_unformed_module(mod);
3240        if (err)
3241                goto free_module;
3242
3243#ifdef CONFIG_MODULE_SIG
3244        mod->sig_ok = info->sig_ok;
3245        if (!mod->sig_ok) {
3246                printk_once(KERN_NOTICE
3247                            "%s: module verification failed: signature and/or"
3248                            " required key missing - tainting kernel\n",
3249                            mod->name);
3250                add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_STILL_OK);
3251        }
3252#endif
3253
3254        /* To avoid stressing percpu allocator, do this once we're unique. */
3255        err = percpu_modalloc(mod, info);
3256        if (err)
3257                goto unlink_mod;
3258
3259        /* Now module is in final location, initialize linked lists, etc. */
3260        err = module_unload_init(mod);
3261        if (err)
3262                goto unlink_mod;
3263
3264        /* Now we've got everything in the final locations, we can
3265         * find optional sections. */
3266        find_module_sections(mod, info);
3267
3268        err = check_module_license_and_versions(mod);
3269        if (err)
3270                goto free_unload;
3271
3272        /* Set up MODINFO_ATTR fields */
3273        setup_modinfo(mod, info);
3274
3275        /* Fix up syms, so that st_value is a pointer to location. */
3276        err = simplify_symbols(mod, info);
3277        if (err < 0)
3278                goto free_modinfo;
3279
3280        err = apply_relocations(mod, info);
3281        if (err < 0)
3282                goto free_modinfo;
3283
3284        err = post_relocation(mod, info);
3285        if (err < 0)
3286                goto free_modinfo;
3287
3288        flush_module_icache(mod);
3289
3290        /* Now copy in args */
3291        mod->args = strndup_user(uargs, ~0UL >> 1);
3292        if (IS_ERR(mod->args)) {
3293                err = PTR_ERR(mod->args);
3294                goto free_arch_cleanup;
3295        }
3296
3297        dynamic_debug_setup(info->debug, info->num_debug);
3298
3299        /* Finally it's fully formed, ready to start executing. */
3300        err = complete_formation(mod, info);
3301        if (err)
3302                goto ddebug_cleanup;
3303
3304        /* Module is ready to execute: parsing args may do that. */
3305        err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
3306                         -32768, 32767, unknown_module_param_cb);
3307        if (err < 0)
3308                goto bug_cleanup;
3309
3310        /* Link in to syfs. */
3311        err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3312        if (err < 0)
3313                goto bug_cleanup;
3314
3315        /* Get rid of temporary copy. */
3316        free_copy(info);
3317
3318        /* Done! */
3319        trace_module_load(mod);
3320
3321        return do_init_module(mod);
3322
3323 bug_cleanup:
3324        /* module_bug_cleanup needs module_mutex protection */
3325        mutex_lock(&module_mutex);
3326        module_bug_cleanup(mod);
3327        mutex_unlock(&module_mutex);
3328 ddebug_cleanup:
3329        dynamic_debug_remove(info->debug);
3330        synchronize_sched();
3331        kfree(mod->args);
3332 free_arch_cleanup:
3333        module_arch_cleanup(mod);
3334 free_modinfo:
3335        free_modinfo(mod);
3336 free_unload:
3337        module_unload_free(mod);
3338 unlink_mod:
3339        mutex_lock(&module_mutex);
3340        /* Unlink carefully: kallsyms could be walking list. */
3341        list_del_rcu(&mod->list);
3342        wake_up_all(&module_wq);
3343        mutex_unlock(&module_mutex);
3344 free_module:
3345        module_deallocate(mod, info);
3346 free_copy:
3347        free_copy(info);
3348        return err;
3349}
3350
3351SYSCALL_DEFINE3(init_module, void __user *, umod,
3352                unsigned long, len, const char __user *, uargs)
3353{
3354        int err;
3355        struct load_info info = { };
3356
3357        err = may_init_module();
3358        if (err)
3359                return err;
3360
3361        pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3362               umod, len, uargs);
3363
3364        err = copy_module_from_user(umod, len, &info);
3365        if (err)
3366                return err;
3367
3368        return load_module(&info, uargs, 0);
3369}
3370
3371SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3372{
3373        int err;
3374        struct load_info info = { };
3375
3376        err = may_init_module();
3377        if (err)
3378                return err;
3379
3380        pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3381
3382        if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3383                      |MODULE_INIT_IGNORE_VERMAGIC))
3384                return -EINVAL;
3385
3386        err = copy_module_from_fd(fd, &info);
3387        if (err)
3388                return err;
3389
3390        return load_module(&info, uargs, flags);
3391}
3392
3393static inline int within(unsigned long addr, void *start, unsigned long size)
3394{
3395        return ((void *)addr >= start && (void *)addr < start + size);
3396}
3397
3398#ifdef CONFIG_KALLSYMS
3399/*
3400 * This ignores the intensely annoying "mapping symbols" found
3401 * in ARM ELF files: $a, $t and $d.
3402 */
3403static inline int is_arm_mapping_symbol(const char *str)
3404{
3405        return str[0] == '$' && strchr("atd", str[1])
3406               && (str[2] == '\0' || str[2] == '.');
3407}
3408
3409static const char *get_ksymbol(struct module *mod,
3410                               unsigned long addr,
3411                               unsigned long *size,
3412                               unsigned long *offset)
3413{
3414        unsigned int i, best = 0;
3415        unsigned long nextval;
3416
3417        /* At worse, next value is at end of module */
3418        if (within_module_init(addr, mod))
3419                nextval = (unsigned long)mod->module_init+mod->init_text_size;
3420        else
3421                nextval = (unsigned long)mod->module_core+mod->core_text_size;
3422
3423        /* Scan for closest preceding symbol, and next symbol. (ELF
3424           starts real symbols at 1). */
3425        for (i = 1; i < mod->num_symtab; i++) {
3426                if (mod->symtab[i].st_shndx == SHN_UNDEF)
3427                        continue;
3428
3429                /* We ignore unnamed symbols: they're uninformative
3430                 * and inserted at a whim. */
3431                if (mod->symtab[i].st_value <= addr
3432                    && mod->symtab[i].st_value > mod->symtab[best].st_value
3433                    && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3434                    && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3435                        best = i;
3436                if (mod->symtab[i].st_value > addr
3437                    && mod->symtab[i].st_value < nextval
3438                    && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3439                    && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3440                        nextval = mod->symtab[i].st_value;
3441        }
3442
3443        if (!best)
3444                return NULL;
3445
3446        if (size)
3447                *size = nextval - mod->symtab[best].st_value;
3448        if (offset)
3449                *offset = addr - mod->symtab[best].st_value;
3450        return mod->strtab + mod->symtab[best].st_name;
3451}
3452
3453/* For kallsyms to ask for address resolution.  NULL means not found.  Careful
3454 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3455const char *module_address_lookup(unsigned long addr,
3456                            unsigned long *size,
3457                            unsigned long *offset,
3458                            char **modname,
3459                            char *namebuf)
3460{
3461        struct module *mod;
3462        const char *ret = NULL;
3463
3464        preempt_disable();
3465        list_for_each_entry_rcu(mod, &modules, list) {
3466                if (mod->state == MODULE_STATE_UNFORMED)
3467                        continue;
3468                if (within_module_init(addr, mod) ||
3469                    within_module_core(addr, mod)) {
3470                        if (modname)
3471                                *modname = mod->name;
3472                        ret = get_ksymbol(mod, addr, size, offset);
3473                        break;
3474                }
3475        }
3476        /* Make a copy in here where it's safe */
3477        if (ret) {
3478                strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
3479                ret = namebuf;
3480        }
3481        preempt_enable();
3482        return ret;
3483}
3484
3485int lookup_module_symbol_name(unsigned long addr, char *symname)
3486{
3487        struct module *mod;
3488
3489        preempt_disable();
3490        list_for_each_entry_rcu(mod, &modules, list) {
3491                if (mod->state == MODULE_STATE_UNFORMED)
3492                        continue;
3493                if (within_module_init(addr, mod) ||
3494                    within_module_core(addr, mod)) {
3495                        const char *sym;
3496
3497                        sym = get_ksymbol(mod, addr, NULL, NULL);
3498                        if (!sym)
3499                                goto out;
3500                        strlcpy(symname, sym, KSYM_NAME_LEN);
3501                        preempt_enable();
3502                        return 0;
3503                }
3504        }
3505out:
3506        preempt_enable();
3507        return -ERANGE;
3508}
3509
3510int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
3511                        unsigned long *offset, char *modname, char *name)
3512{
3513        struct module *mod;
3514
3515        preempt_disable();
3516        list_for_each_entry_rcu(mod, &modules, list) {
3517                if (mod->state == MODULE_STATE_UNFORMED)
3518                        continue;
3519                if (within_module_init(addr, mod) ||
3520                    within_module_core(addr, mod)) {
3521                        const char *sym;
3522
3523                        sym = get_ksymbol(mod, addr, size, offset);
3524                        if (!sym)
3525                                goto out;
3526                        if (modname)
3527                                strlcpy(modname, mod->name, MODULE_NAME_LEN);
3528                        if (name)
3529                                strlcpy(name, sym, KSYM_NAME_LEN);
3530                        preempt_enable();
3531                        return 0;
3532                }
3533        }
3534out:
3535        preempt_enable();
3536        return -ERANGE;
3537}
3538
3539int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
3540                        char *name, char *module_name, int *exported)
3541{
3542        struct module *mod;
3543
3544        preempt_disable();
3545        list_for_each_entry_rcu(mod, &modules, list) {
3546                if (mod->state == MODULE_STATE_UNFORMED)
3547                        continue;
3548                if (symnum < mod->num_symtab) {
3549                        *value = mod->symtab[symnum].st_value;
3550                        *type = mod->symtab[symnum].st_info;
3551                        strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
3552                                KSYM_NAME_LEN);
3553                        strlcpy(module_name, mod->name, MODULE_NAME_LEN);
3554                        *exported = is_exported(name, *value, mod);
3555                        preempt_enable();
3556                        return 0;
3557                }
3558                symnum -= mod->num_symtab;
3559        }
3560        preempt_enable();
3561        return -ERANGE;
3562}
3563
3564static unsigned long mod_find_symname(struct module *mod, const char *name)
3565{
3566        unsigned int i;
3567
3568        for (i = 0; i < mod->num_symtab; i++)
3569                if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
3570                    mod->symtab[i].st_info != 'U')
3571                        return mod->symtab[i].st_value;
3572        return 0;
3573}
3574
3575/* Look for this name: can be of form module:name. */
3576unsigned long module_kallsyms_lookup_name(const char *name)
3577{
3578        struct module *mod;
3579        char *colon;
3580        unsigned long ret = 0;
3581
3582        /* Don't lock: we're in enough trouble already. */
3583        preempt_disable();
3584        if ((colon = strchr(name, ':')) != NULL) {
3585                if ((mod = find_module_all(name, colon - name, false)) != NULL)
3586                        ret = mod_find_symname(mod, colon+1);
3587        } else {
3588                list_for_each_entry_rcu(mod, &modules, list) {
3589                        if (mod->state == MODULE_STATE_UNFORMED)
3590                                continue;
3591                        if ((ret = mod_find_symname(mod, name)) != 0)
3592                                break;
3593                }
3594        }
3595        preempt_enable();
3596        return ret;
3597}
3598
3599int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3600                                             struct module *, unsigned long),
3601                                   void *data)
3602{
3603        struct module *mod;
3604        unsigned int i;
3605        int ret;
3606
3607        list_for_each_entry(mod, &modules, list) {
3608                if (mod->state == MODULE_STATE_UNFORMED)
3609                        continue;
3610                for (i = 0; i < mod->num_symtab; i++) {
3611                        ret = fn(data, mod->strtab + mod->symtab[i].st_name,
3612                                 mod, mod->symtab[i].st_value);
3613                        if (ret != 0)
3614                                return ret;
3615                }
3616        }
3617        return 0;
3618}
3619#endif /* CONFIG_KALLSYMS */
3620
3621static char *module_flags(struct module *mod, char *buf)
3622{
3623        int bx = 0;
3624
3625        BUG_ON(mod->state == MODULE_STATE_UNFORMED);
3626        if (mod->taints ||
3627            mod->state == MODULE_STATE_GOING ||
3628            mod->state == MODULE_STATE_COMING) {
3629                buf[bx++] = '(';
3630                bx += module_flags_taint(mod, buf + bx);
3631                /* Show a - for module-is-being-unloaded */
3632                if (mod->state == MODULE_STATE_GOING)
3633                        buf[bx++] = '-';
3634                /* Show a + for module-is-being-loaded */
3635                if (mod->state == MODULE_STATE_COMING)
3636                        buf[bx++] = '+';
3637                buf[bx++] = ')';
3638        }
3639        buf[bx] = '\0';
3640
3641        return buf;
3642}
3643
3644#ifdef CONFIG_PROC_FS
3645/* Called by the /proc file system to return a list of modules. */
3646static void *m_start(struct seq_file *m, loff_t *pos)
3647{
3648        mutex_lock(&module_mutex);
3649        return seq_list_start(&modules, *pos);
3650}
3651
3652static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3653{
3654        return seq_list_next(p, &modules, pos);
3655}
3656
3657static void m_stop(struct seq_file *m, void *p)
3658{
3659        mutex_unlock(&module_mutex);
3660}
3661
3662static int m_show(struct seq_file *m, void *p)
3663{
3664        struct module *mod = list_entry(p, struct module, list);
3665        char buf[8];
3666
3667        /* We always ignore unformed modules. */
3668        if (mod->state == MODULE_STATE_UNFORMED)
3669                return 0;
3670
3671        seq_printf(m, "%s %u",
3672                   mod->name, mod->init_size + mod->core_size);
3673        print_unload_info(m, mod);
3674
3675        /* Informative for users. */
3676        seq_printf(m, " %s",
3677                   mod->state == MODULE_STATE_GOING ? "Unloading":
3678                   mod->state == MODULE_STATE_COMING ? "Loading":
3679                   "Live");
3680        /* Used by oprofile and other similar tools. */
3681        seq_printf(m, " 0x%pK", mod->module_core);
3682
3683        /* Taints info */
3684        if (mod->taints)
3685                seq_printf(m, " %s", module_flags(mod, buf));
3686
3687        seq_printf(m, "\n");
3688        return 0;
3689}
3690
3691/* Format: modulename size refcount deps address
3692
3693   Where refcount is a number or -, and deps is a comma-separated list
3694   of depends or -.
3695*/
3696static const struct seq_operations modules_op = {
3697        .start  = m_start,
3698        .next   = m_next,
3699        .stop   = m_stop,
3700        .show   = m_show
3701};
3702
3703static int modules_open(struct inode *inode, struct file *file)
3704{
3705        return seq_open(file, &modules_op);
3706}
3707
3708static const struct file_operations proc_modules_operations = {
3709        .open           = modules_open,
3710        .read           = seq_read,
3711        .llseek         = seq_lseek,
3712        .release        = seq_release,
3713};
3714
3715static int __init proc_modules_init(void)
3716{
3717        proc_create("modules", 0, NULL, &proc_modules_operations);
3718        return 0;
3719}
3720module_init(proc_modules_init);
3721#endif
3722
3723/* Given an address, look for it in the module exception tables. */
3724const struct exception_table_entry *search_module_extables(unsigned long addr)
3725{
3726        const struct exception_table_entry *e = NULL;
3727        struct module *mod;
3728
3729        preempt_disable();
3730        list_for_each_entry_rcu(mod, &modules, list) {
3731                if (mod->state == MODULE_STATE_UNFORMED)
3732                        continue;
3733                if (mod->num_exentries == 0)
3734                        continue;
3735
3736                e = search_extable(mod->extable,
3737                                   mod->extable + mod->num_exentries - 1,
3738                                   addr);
3739                if (e)
3740                        break;
3741        }
3742        preempt_enable();
3743
3744        /* Now, if we found one, we are running inside it now, hence
3745           we cannot unload the module, hence no refcnt needed. */
3746        return e;
3747}
3748
3749/*
3750 * is_module_address - is this address inside a module?
3751 * @addr: the address to check.
3752 *
3753 * See is_module_text_address() if you simply want to see if the address
3754 * is code (not data).
3755 */
3756bool is_module_address(unsigned long addr)
3757{
3758        bool ret;
3759
3760        preempt_disable();
3761        ret = __module_address(addr) != NULL;
3762        preempt_enable();
3763
3764        return ret;
3765}
3766
3767/*
3768 * __module_address - get the module which contains an address.
3769 * @addr: the address.
3770 *
3771 * Must be called with preempt disabled or module mutex held so that
3772 * module doesn't get freed during this.
3773 */
3774struct module *__module_address(unsigned long addr)
3775{
3776        struct module *mod;
3777
3778        if (addr < module_addr_min || addr > module_addr_max)
3779                return NULL;
3780
3781        list_for_each_entry_rcu(mod, &modules, list) {
3782                if (mod->state == MODULE_STATE_UNFORMED)
3783                        continue;
3784                if (within_module_core(addr, mod)
3785                    || within_module_init(addr, mod))
3786                        return mod;
3787        }
3788        return NULL;
3789}
3790EXPORT_SYMBOL_GPL(__module_address);
3791
3792/*
3793 * is_module_text_address - is this address inside module code?
3794 * @addr: the address to check.
3795 *
3796 * See is_module_address() if you simply want to see if the address is
3797 * anywhere in a module.  See kernel_text_address() for testing if an
3798 * address corresponds to kernel or module code.
3799 */
3800bool is_module_text_address(unsigned long addr)
3801{
3802        bool ret;
3803
3804        preempt_disable();
3805        ret = __module_text_address(addr) != NULL;
3806        preempt_enable();
3807
3808        return ret;
3809}
3810
3811/*
3812 * __module_text_address - get the module whose code contains an address.
3813 * @addr: the address.
3814 *
3815 * Must be called with preempt disabled or module mutex held so that
3816 * module doesn't get freed during this.
3817 */
3818struct module *__module_text_address(unsigned long addr)
3819{
3820        struct module *mod = __module_address(addr);
3821        if (mod) {
3822                /* Make sure it's within the text section. */
3823                if (!within(addr, mod->module_init, mod->init_text_size)
3824                    && !within(addr, mod->module_core, mod->core_text_size))
3825                        mod = NULL;
3826        }
3827        return mod;
3828}
3829EXPORT_SYMBOL_GPL(__module_text_address);
3830
3831/* Don't grab lock, we're oopsing. */
3832void print_modules(void)
3833{
3834        struct module *mod;
3835        char buf[8];
3836
3837        printk(KERN_DEFAULT "Modules linked in:");
3838        /* Most callers should already have preempt disabled, but make sure */
3839        preempt_disable();
3840        list_for_each_entry_rcu(mod, &modules, list) {
3841                if (mod->state == MODULE_STATE_UNFORMED)
3842                        continue;
3843                printk(" %s%s", mod->name, module_flags(mod, buf));
3844        }
3845        preempt_enable();
3846        if (last_unloaded_module[0])
3847                printk(" [last unloaded: %s]", last_unloaded_module);
3848        printk("\n");
3849}
3850
3851#ifdef CONFIG_MODVERSIONS
3852/* Generate the signature for all relevant module structures here.
3853 * If these change, we don't want to try to parse the module. */
3854void module_layout(struct module *mod,
3855                   struct modversion_info *ver,
3856                   struct kernel_param *kp,
3857                   struct kernel_symbol *ks,
3858                   struct tracepoint * const *tp)
3859{
3860}
3861EXPORT_SYMBOL(module_layout);
3862#endif
3863
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