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