2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.
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.
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.
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
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>
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>
59 #define CREATE_TRACE_POINTS
60 #include <trace/events/module.h>
65 #define DEBUGP(fmt , a...)
68 #ifndef ARCH_SHF_SMALL
69 #define ARCH_SHF_SMALL 0
72 /* If this is set, the section belongs in the init part of the module */
73 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
75 /* List of modules, protected by module_mutex or preempt_disable
76 * (delete uses stop_machine/add uses RCU list operations). */
77 DEFINE_MUTEX(module_mutex);
78 EXPORT_SYMBOL_GPL(module_mutex);
79 static LIST_HEAD(modules);
80 #ifdef CONFIG_KGDB_KDB
81 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
82 #endif /* CONFIG_KGDB_KDB */
85 /* Block module loading/unloading? */
86 int modules_disabled = 0;
88 /* Waiting for a module to finish initializing? */
89 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
91 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
93 /* Bounds of module allocation, for speeding __module_address */
94 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
96 int register_module_notifier(struct notifier_block * nb)
98 return blocking_notifier_chain_register(&module_notify_list, nb);
100 EXPORT_SYMBOL(register_module_notifier);
102 int unregister_module_notifier(struct notifier_block * nb)
104 return blocking_notifier_chain_unregister(&module_notify_list, nb);
106 EXPORT_SYMBOL(unregister_module_notifier);
108 /* We require a truly strong try_module_get(): 0 means failure due to
109 ongoing or failed initialization etc. */
110 static inline int strong_try_module_get(struct module *mod)
112 if (mod && mod->state == MODULE_STATE_COMING)
114 if (try_module_get(mod))
120 static inline void add_taint_module(struct module *mod, unsigned flag)
123 mod->taints |= (1U << flag);
127 * A thread that wants to hold a reference to a module only while it
128 * is running can call this to safely exit. nfsd and lockd use this.
130 void __module_put_and_exit(struct module *mod, long code)
135 EXPORT_SYMBOL(__module_put_and_exit);
137 /* Find a module section: 0 means not found. */
138 static unsigned int find_sec(Elf_Ehdr *hdr,
140 const char *secstrings,
145 for (i = 1; i < hdr->e_shnum; i++)
146 /* Alloc bit cleared means "ignore it." */
147 if ((sechdrs[i].sh_flags & SHF_ALLOC)
148 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
153 /* Find a module section, or NULL. */
154 static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
155 const char *secstrings, const char *name)
157 /* Section 0 has sh_addr 0. */
158 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
161 /* Find a module section, or NULL. Fill in number of "objects" in section. */
162 static void *section_objs(Elf_Ehdr *hdr,
164 const char *secstrings,
169 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
171 /* Section 0 has sh_addr 0 and sh_size 0. */
172 *num = sechdrs[sec].sh_size / object_size;
173 return (void *)sechdrs[sec].sh_addr;
176 /* Provided by the linker */
177 extern const struct kernel_symbol __start___ksymtab[];
178 extern const struct kernel_symbol __stop___ksymtab[];
179 extern const struct kernel_symbol __start___ksymtab_gpl[];
180 extern const struct kernel_symbol __stop___ksymtab_gpl[];
181 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
182 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
183 extern const unsigned long __start___kcrctab[];
184 extern const unsigned long __start___kcrctab_gpl[];
185 extern const unsigned long __start___kcrctab_gpl_future[];
186 #ifdef CONFIG_UNUSED_SYMBOLS
187 extern const struct kernel_symbol __start___ksymtab_unused[];
188 extern const struct kernel_symbol __stop___ksymtab_unused[];
189 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
190 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
191 extern const unsigned long __start___kcrctab_unused[];
192 extern const unsigned long __start___kcrctab_unused_gpl[];
195 #ifndef CONFIG_MODVERSIONS
196 #define symversion(base, idx) NULL
198 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
201 static bool each_symbol_in_section(const struct symsearch *arr,
202 unsigned int arrsize,
203 struct module *owner,
204 bool (*fn)(const struct symsearch *syms,
205 struct module *owner,
206 unsigned int symnum, void *data),
211 for (j = 0; j < arrsize; j++) {
212 for (i = 0; i < arr[j].stop - arr[j].start; i++)
213 if (fn(&arr[j], owner, i, data))
220 /* Returns true as soon as fn returns true, otherwise false. */
221 bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
222 unsigned int symnum, void *data), void *data)
225 const struct symsearch arr[] = {
226 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
227 NOT_GPL_ONLY, false },
228 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
229 __start___kcrctab_gpl,
231 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
232 __start___kcrctab_gpl_future,
233 WILL_BE_GPL_ONLY, false },
234 #ifdef CONFIG_UNUSED_SYMBOLS
235 { __start___ksymtab_unused, __stop___ksymtab_unused,
236 __start___kcrctab_unused,
237 NOT_GPL_ONLY, true },
238 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
239 __start___kcrctab_unused_gpl,
244 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
247 list_for_each_entry_rcu(mod, &modules, list) {
248 struct symsearch arr[] = {
249 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
250 NOT_GPL_ONLY, false },
251 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
254 { mod->gpl_future_syms,
255 mod->gpl_future_syms + mod->num_gpl_future_syms,
256 mod->gpl_future_crcs,
257 WILL_BE_GPL_ONLY, false },
258 #ifdef CONFIG_UNUSED_SYMBOLS
260 mod->unused_syms + mod->num_unused_syms,
262 NOT_GPL_ONLY, true },
263 { mod->unused_gpl_syms,
264 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
265 mod->unused_gpl_crcs,
270 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
275 EXPORT_SYMBOL_GPL(each_symbol);
277 struct find_symbol_arg {
284 struct module *owner;
285 const unsigned long *crc;
286 const struct kernel_symbol *sym;
289 static bool find_symbol_in_section(const struct symsearch *syms,
290 struct module *owner,
291 unsigned int symnum, void *data)
293 struct find_symbol_arg *fsa = data;
295 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
299 if (syms->licence == GPL_ONLY)
301 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
302 printk(KERN_WARNING "Symbol %s is being used "
303 "by a non-GPL module, which will not "
304 "be allowed in the future\n", fsa->name);
305 printk(KERN_WARNING "Please see the file "
306 "Documentation/feature-removal-schedule.txt "
307 "in the kernel source tree for more details.\n");
311 #ifdef CONFIG_UNUSED_SYMBOLS
312 if (syms->unused && fsa->warn) {
313 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
314 "however this module is using it.\n", fsa->name);
316 "This symbol will go away in the future.\n");
318 "Please evalute if this is the right api to use and if "
319 "it really is, submit a report the linux kernel "
320 "mailinglist together with submitting your code for "
326 fsa->crc = symversion(syms->crcs, symnum);
327 fsa->sym = &syms->start[symnum];
331 /* Find a symbol and return it, along with, (optional) crc and
332 * (optional) module which owns it */
333 const struct kernel_symbol *find_symbol(const char *name,
334 struct module **owner,
335 const unsigned long **crc,
339 struct find_symbol_arg fsa;
345 if (each_symbol(find_symbol_in_section, &fsa)) {
353 DEBUGP("Failed to find symbol %s\n", name);
356 EXPORT_SYMBOL_GPL(find_symbol);
358 /* Search for module by name: must hold module_mutex. */
359 struct module *find_module(const char *name)
363 list_for_each_entry(mod, &modules, list) {
364 if (strcmp(mod->name, name) == 0)
369 EXPORT_SYMBOL_GPL(find_module);
373 static inline void __percpu *mod_percpu(struct module *mod)
378 static int percpu_modalloc(struct module *mod,
379 unsigned long size, unsigned long align)
381 if (align > PAGE_SIZE) {
382 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
383 mod->name, align, PAGE_SIZE);
387 mod->percpu = __alloc_reserved_percpu(size, align);
390 "Could not allocate %lu bytes percpu data\n", size);
393 mod->percpu_size = size;
397 static void percpu_modfree(struct module *mod)
399 free_percpu(mod->percpu);
402 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
404 const char *secstrings)
406 return find_sec(hdr, sechdrs, secstrings, ".data..percpu");
409 static void percpu_modcopy(struct module *mod,
410 const void *from, unsigned long size)
414 for_each_possible_cpu(cpu)
415 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
419 * is_module_percpu_address - test whether address is from module static percpu
420 * @addr: address to test
422 * Test whether @addr belongs to module static percpu area.
425 * %true if @addr is from module static percpu area
427 bool is_module_percpu_address(unsigned long addr)
434 list_for_each_entry_rcu(mod, &modules, list) {
435 if (!mod->percpu_size)
437 for_each_possible_cpu(cpu) {
438 void *start = per_cpu_ptr(mod->percpu, cpu);
440 if ((void *)addr >= start &&
441 (void *)addr < start + mod->percpu_size) {
452 #else /* ... !CONFIG_SMP */
454 static inline void __percpu *mod_percpu(struct module *mod)
458 static inline int percpu_modalloc(struct module *mod,
459 unsigned long size, unsigned long align)
463 static inline void percpu_modfree(struct module *mod)
466 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
468 const char *secstrings)
472 static inline void percpu_modcopy(struct module *mod,
473 const void *from, unsigned long size)
475 /* pcpusec should be 0, and size of that section should be 0. */
478 bool is_module_percpu_address(unsigned long addr)
483 #endif /* CONFIG_SMP */
485 #define MODINFO_ATTR(field) \
486 static void setup_modinfo_##field(struct module *mod, const char *s) \
488 mod->field = kstrdup(s, GFP_KERNEL); \
490 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
491 struct module *mod, char *buffer) \
493 return sprintf(buffer, "%s\n", mod->field); \
495 static int modinfo_##field##_exists(struct module *mod) \
497 return mod->field != NULL; \
499 static void free_modinfo_##field(struct module *mod) \
504 static struct module_attribute modinfo_##field = { \
505 .attr = { .name = __stringify(field), .mode = 0444 }, \
506 .show = show_modinfo_##field, \
507 .setup = setup_modinfo_##field, \
508 .test = modinfo_##field##_exists, \
509 .free = free_modinfo_##field, \
512 MODINFO_ATTR(version);
513 MODINFO_ATTR(srcversion);
515 static char last_unloaded_module[MODULE_NAME_LEN+1];
517 #ifdef CONFIG_MODULE_UNLOAD
519 EXPORT_TRACEPOINT_SYMBOL(module_get);
521 /* Init the unload section of the module. */
522 static void module_unload_init(struct module *mod)
526 INIT_LIST_HEAD(&mod->source_list);
527 INIT_LIST_HEAD(&mod->target_list);
528 for_each_possible_cpu(cpu) {
529 per_cpu_ptr(mod->refptr, cpu)->incs = 0;
530 per_cpu_ptr(mod->refptr, cpu)->decs = 0;
533 /* Hold reference count during initialization. */
534 __this_cpu_write(mod->refptr->incs, 1);
535 /* Backwards compatibility macros put refcount during init. */
536 mod->waiter = current;
539 /* Does a already use b? */
540 static int already_uses(struct module *a, struct module *b)
542 struct module_use *use;
544 list_for_each_entry(use, &b->source_list, source_list) {
545 if (use->source == a) {
546 DEBUGP("%s uses %s!\n", a->name, b->name);
550 DEBUGP("%s does not use %s!\n", a->name, b->name);
556 * - we add 'a' as a "source", 'b' as a "target" of module use
557 * - the module_use is added to the list of 'b' sources (so
558 * 'b' can walk the list to see who sourced them), and of 'a'
559 * targets (so 'a' can see what modules it targets).
561 static int add_module_usage(struct module *a, struct module *b)
563 struct module_use *use;
565 DEBUGP("Allocating new usage for %s.\n", a->name);
566 use = kmalloc(sizeof(*use), GFP_ATOMIC);
568 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
574 list_add(&use->source_list, &b->source_list);
575 list_add(&use->target_list, &a->target_list);
579 /* Module a uses b */
580 int use_module(struct module *a, struct module *b)
584 if (b == NULL || already_uses(a, b)) return 1;
586 /* If we're interrupted or time out, we fail. */
587 if (wait_event_interruptible_timeout(
588 module_wq, (err = strong_try_module_get(b)) != -EBUSY,
590 printk("%s: gave up waiting for init of module %s.\n",
595 /* If strong_try_module_get() returned a different error, we fail. */
599 err = add_module_usage(a, b);
606 EXPORT_SYMBOL_GPL(use_module);
608 /* Clear the unload stuff of the module. */
609 static void module_unload_free(struct module *mod)
611 struct module_use *use, *tmp;
613 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
614 struct module *i = use->target;
615 DEBUGP("%s unusing %s\n", mod->name, i->name);
617 list_del(&use->source_list);
618 list_del(&use->target_list);
623 #ifdef CONFIG_MODULE_FORCE_UNLOAD
624 static inline int try_force_unload(unsigned int flags)
626 int ret = (flags & O_TRUNC);
628 add_taint(TAINT_FORCED_RMMOD);
632 static inline int try_force_unload(unsigned int flags)
636 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
645 /* Whole machine is stopped with interrupts off when this runs. */
646 static int __try_stop_module(void *_sref)
648 struct stopref *sref = _sref;
650 /* If it's not unused, quit unless we're forcing. */
651 if (module_refcount(sref->mod) != 0) {
652 if (!(*sref->forced = try_force_unload(sref->flags)))
656 /* Mark it as dying. */
657 sref->mod->state = MODULE_STATE_GOING;
661 static int try_stop_module(struct module *mod, int flags, int *forced)
663 if (flags & O_NONBLOCK) {
664 struct stopref sref = { mod, flags, forced };
666 return stop_machine(__try_stop_module, &sref, NULL);
668 /* We don't need to stop the machine for this. */
669 mod->state = MODULE_STATE_GOING;
675 unsigned int module_refcount(struct module *mod)
677 unsigned int incs = 0, decs = 0;
680 for_each_possible_cpu(cpu)
681 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
683 * ensure the incs are added up after the decs.
684 * module_put ensures incs are visible before decs with smp_wmb.
686 * This 2-count scheme avoids the situation where the refcount
687 * for CPU0 is read, then CPU0 increments the module refcount,
688 * then CPU1 drops that refcount, then the refcount for CPU1 is
689 * read. We would record a decrement but not its corresponding
690 * increment so we would see a low count (disaster).
692 * Rare situation? But module_refcount can be preempted, and we
693 * might be tallying up 4096+ CPUs. So it is not impossible.
696 for_each_possible_cpu(cpu)
697 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
700 EXPORT_SYMBOL(module_refcount);
702 /* This exists whether we can unload or not */
703 static void free_module(struct module *mod);
705 static void wait_for_zero_refcount(struct module *mod)
707 /* Since we might sleep for some time, release the mutex first */
708 mutex_unlock(&module_mutex);
710 DEBUGP("Looking at refcount...\n");
711 set_current_state(TASK_UNINTERRUPTIBLE);
712 if (module_refcount(mod) == 0)
716 current->state = TASK_RUNNING;
717 mutex_lock(&module_mutex);
720 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
724 char name[MODULE_NAME_LEN];
727 if (!capable(CAP_SYS_MODULE) || modules_disabled)
730 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
732 name[MODULE_NAME_LEN-1] = '\0';
734 if (mutex_lock_interruptible(&module_mutex) != 0)
737 mod = find_module(name);
743 if (!list_empty(&mod->source_list)) {
744 /* Other modules depend on us: get rid of them first. */
749 /* Doing init or already dying? */
750 if (mod->state != MODULE_STATE_LIVE) {
751 /* FIXME: if (force), slam module count and wake up
753 DEBUGP("%s already dying\n", mod->name);
758 /* If it has an init func, it must have an exit func to unload */
759 if (mod->init && !mod->exit) {
760 forced = try_force_unload(flags);
762 /* This module can't be removed */
768 /* Set this up before setting mod->state */
769 mod->waiter = current;
771 /* Stop the machine so refcounts can't move and disable module. */
772 ret = try_stop_module(mod, flags, &forced);
776 /* Never wait if forced. */
777 if (!forced && module_refcount(mod) != 0)
778 wait_for_zero_refcount(mod);
780 mutex_unlock(&module_mutex);
781 /* Final destruction now noone is using it. */
782 if (mod->exit != NULL)
784 blocking_notifier_call_chain(&module_notify_list,
785 MODULE_STATE_GOING, mod);
786 async_synchronize_full();
787 mutex_lock(&module_mutex);
788 /* Store the name of the last unloaded module for diagnostic purposes */
789 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
790 ddebug_remove_module(mod->name);
794 mutex_unlock(&module_mutex);
798 static inline void print_unload_info(struct seq_file *m, struct module *mod)
800 struct module_use *use;
801 int printed_something = 0;
803 seq_printf(m, " %u ", module_refcount(mod));
805 /* Always include a trailing , so userspace can differentiate
806 between this and the old multi-field proc format. */
807 list_for_each_entry(use, &mod->source_list, source_list) {
808 printed_something = 1;
809 seq_printf(m, "%s,", use->source->name);
812 if (mod->init != NULL && mod->exit == NULL) {
813 printed_something = 1;
814 seq_printf(m, "[permanent],");
817 if (!printed_something)
821 void __symbol_put(const char *symbol)
823 struct module *owner;
826 if (!find_symbol(symbol, &owner, NULL, true, false))
831 EXPORT_SYMBOL(__symbol_put);
833 /* Note this assumes addr is a function, which it currently always is. */
834 void symbol_put_addr(void *addr)
836 struct module *modaddr;
837 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
839 if (core_kernel_text(a))
842 /* module_text_address is safe here: we're supposed to have reference
843 * to module from symbol_get, so it can't go away. */
844 modaddr = __module_text_address(a);
848 EXPORT_SYMBOL_GPL(symbol_put_addr);
850 static ssize_t show_refcnt(struct module_attribute *mattr,
851 struct module *mod, char *buffer)
853 return sprintf(buffer, "%u\n", module_refcount(mod));
856 static struct module_attribute refcnt = {
857 .attr = { .name = "refcnt", .mode = 0444 },
861 void module_put(struct module *module)
865 smp_wmb(); /* see comment in module_refcount */
866 __this_cpu_inc(module->refptr->decs);
868 trace_module_put(module, _RET_IP_);
869 /* Maybe they're waiting for us to drop reference? */
870 if (unlikely(!module_is_live(module)))
871 wake_up_process(module->waiter);
875 EXPORT_SYMBOL(module_put);
877 #else /* !CONFIG_MODULE_UNLOAD */
878 static inline void print_unload_info(struct seq_file *m, struct module *mod)
880 /* We don't know the usage count, or what modules are using. */
881 seq_printf(m, " - -");
884 static inline void module_unload_free(struct module *mod)
888 int use_module(struct module *a, struct module *b)
890 return strong_try_module_get(b) == 0;
892 EXPORT_SYMBOL_GPL(use_module);
894 static inline void module_unload_init(struct module *mod)
897 #endif /* CONFIG_MODULE_UNLOAD */
899 static ssize_t show_initstate(struct module_attribute *mattr,
900 struct module *mod, char *buffer)
902 const char *state = "unknown";
904 switch (mod->state) {
905 case MODULE_STATE_LIVE:
908 case MODULE_STATE_COMING:
911 case MODULE_STATE_GOING:
915 return sprintf(buffer, "%s\n", state);
918 static struct module_attribute initstate = {
919 .attr = { .name = "initstate", .mode = 0444 },
920 .show = show_initstate,
923 static struct module_attribute *modinfo_attrs[] = {
927 #ifdef CONFIG_MODULE_UNLOAD
933 static const char vermagic[] = VERMAGIC_STRING;
935 static int try_to_force_load(struct module *mod, const char *reason)
937 #ifdef CONFIG_MODULE_FORCE_LOAD
938 if (!test_taint(TAINT_FORCED_MODULE))
939 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
941 add_taint_module(mod, TAINT_FORCED_MODULE);
948 #ifdef CONFIG_MODVERSIONS
949 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
950 static unsigned long maybe_relocated(unsigned long crc,
951 const struct module *crc_owner)
953 #ifdef ARCH_RELOCATES_KCRCTAB
954 if (crc_owner == NULL)
955 return crc - (unsigned long)reloc_start;
960 static int check_version(Elf_Shdr *sechdrs,
961 unsigned int versindex,
964 const unsigned long *crc,
965 const struct module *crc_owner)
967 unsigned int i, num_versions;
968 struct modversion_info *versions;
970 /* Exporting module didn't supply crcs? OK, we're already tainted. */
974 /* No versions at all? modprobe --force does this. */
976 return try_to_force_load(mod, symname) == 0;
978 versions = (void *) sechdrs[versindex].sh_addr;
979 num_versions = sechdrs[versindex].sh_size
980 / sizeof(struct modversion_info);
982 for (i = 0; i < num_versions; i++) {
983 if (strcmp(versions[i].name, symname) != 0)
986 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
988 DEBUGP("Found checksum %lX vs module %lX\n",
989 maybe_relocated(*crc, crc_owner), versions[i].crc);
993 printk(KERN_WARNING "%s: no symbol version for %s\n",
998 printk("%s: disagrees about version of symbol %s\n",
1003 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1004 unsigned int versindex,
1007 const unsigned long *crc;
1009 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1012 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1016 /* First part is kernel version, which we ignore if module has crcs. */
1017 static inline int same_magic(const char *amagic, const char *bmagic,
1021 amagic += strcspn(amagic, " ");
1022 bmagic += strcspn(bmagic, " ");
1024 return strcmp(amagic, bmagic) == 0;
1027 static inline int check_version(Elf_Shdr *sechdrs,
1028 unsigned int versindex,
1029 const char *symname,
1031 const unsigned long *crc,
1032 const struct module *crc_owner)
1037 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1038 unsigned int versindex,
1044 static inline int same_magic(const char *amagic, const char *bmagic,
1047 return strcmp(amagic, bmagic) == 0;
1049 #endif /* CONFIG_MODVERSIONS */
1051 /* Resolve a symbol for this module. I.e. if we find one, record usage.
1052 Must be holding module_mutex. */
1053 static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
1054 unsigned int versindex,
1058 struct module *owner;
1059 const struct kernel_symbol *sym;
1060 const unsigned long *crc;
1062 sym = find_symbol(name, &owner, &crc,
1063 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1064 /* use_module can fail due to OOM,
1065 or module initialization or unloading */
1067 if (!check_version(sechdrs, versindex, name, mod, crc, owner)
1068 || !use_module(mod, owner))
1075 * /sys/module/foo/sections stuff
1076 * J. Corbet <corbet@lwn.net>
1078 #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1080 static inline bool sect_empty(const Elf_Shdr *sect)
1082 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1085 struct module_sect_attr
1087 struct module_attribute mattr;
1089 unsigned long address;
1092 struct module_sect_attrs
1094 struct attribute_group grp;
1095 unsigned int nsections;
1096 struct module_sect_attr attrs[0];
1099 static ssize_t module_sect_show(struct module_attribute *mattr,
1100 struct module *mod, char *buf)
1102 struct module_sect_attr *sattr =
1103 container_of(mattr, struct module_sect_attr, mattr);
1104 return sprintf(buf, "0x%lx\n", sattr->address);
1107 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1109 unsigned int section;
1111 for (section = 0; section < sect_attrs->nsections; section++)
1112 kfree(sect_attrs->attrs[section].name);
1116 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1117 char *secstrings, Elf_Shdr *sechdrs)
1119 unsigned int nloaded = 0, i, size[2];
1120 struct module_sect_attrs *sect_attrs;
1121 struct module_sect_attr *sattr;
1122 struct attribute **gattr;
1124 /* Count loaded sections and allocate structures */
1125 for (i = 0; i < nsect; i++)
1126 if (!sect_empty(&sechdrs[i]))
1128 size[0] = ALIGN(sizeof(*sect_attrs)
1129 + nloaded * sizeof(sect_attrs->attrs[0]),
1130 sizeof(sect_attrs->grp.attrs[0]));
1131 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1132 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1133 if (sect_attrs == NULL)
1136 /* Setup section attributes. */
1137 sect_attrs->grp.name = "sections";
1138 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1140 sect_attrs->nsections = 0;
1141 sattr = §_attrs->attrs[0];
1142 gattr = §_attrs->grp.attrs[0];
1143 for (i = 0; i < nsect; i++) {
1144 if (sect_empty(&sechdrs[i]))
1146 sattr->address = sechdrs[i].sh_addr;
1147 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1149 if (sattr->name == NULL)
1151 sect_attrs->nsections++;
1152 sysfs_attr_init(&sattr->mattr.attr);
1153 sattr->mattr.show = module_sect_show;
1154 sattr->mattr.store = NULL;
1155 sattr->mattr.attr.name = sattr->name;
1156 sattr->mattr.attr.mode = S_IRUGO;
1157 *(gattr++) = &(sattr++)->mattr.attr;
1161 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1164 mod->sect_attrs = sect_attrs;
1167 free_sect_attrs(sect_attrs);
1170 static void remove_sect_attrs(struct module *mod)
1172 if (mod->sect_attrs) {
1173 sysfs_remove_group(&mod->mkobj.kobj,
1174 &mod->sect_attrs->grp);
1175 /* We are positive that no one is using any sect attrs
1176 * at this point. Deallocate immediately. */
1177 free_sect_attrs(mod->sect_attrs);
1178 mod->sect_attrs = NULL;
1183 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1186 struct module_notes_attrs {
1187 struct kobject *dir;
1189 struct bin_attribute attrs[0];
1192 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1193 struct bin_attribute *bin_attr,
1194 char *buf, loff_t pos, size_t count)
1197 * The caller checked the pos and count against our size.
1199 memcpy(buf, bin_attr->private + pos, count);
1203 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1206 if (notes_attrs->dir) {
1208 sysfs_remove_bin_file(notes_attrs->dir,
1209 ¬es_attrs->attrs[i]);
1210 kobject_put(notes_attrs->dir);
1215 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1216 char *secstrings, Elf_Shdr *sechdrs)
1218 unsigned int notes, loaded, i;
1219 struct module_notes_attrs *notes_attrs;
1220 struct bin_attribute *nattr;
1222 /* failed to create section attributes, so can't create notes */
1223 if (!mod->sect_attrs)
1226 /* Count notes sections and allocate structures. */
1228 for (i = 0; i < nsect; i++)
1229 if (!sect_empty(&sechdrs[i]) &&
1230 (sechdrs[i].sh_type == SHT_NOTE))
1236 notes_attrs = kzalloc(sizeof(*notes_attrs)
1237 + notes * sizeof(notes_attrs->attrs[0]),
1239 if (notes_attrs == NULL)
1242 notes_attrs->notes = notes;
1243 nattr = ¬es_attrs->attrs[0];
1244 for (loaded = i = 0; i < nsect; ++i) {
1245 if (sect_empty(&sechdrs[i]))
1247 if (sechdrs[i].sh_type == SHT_NOTE) {
1248 sysfs_bin_attr_init(nattr);
1249 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1250 nattr->attr.mode = S_IRUGO;
1251 nattr->size = sechdrs[i].sh_size;
1252 nattr->private = (void *) sechdrs[i].sh_addr;
1253 nattr->read = module_notes_read;
1259 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1260 if (!notes_attrs->dir)
1263 for (i = 0; i < notes; ++i)
1264 if (sysfs_create_bin_file(notes_attrs->dir,
1265 ¬es_attrs->attrs[i]))
1268 mod->notes_attrs = notes_attrs;
1272 free_notes_attrs(notes_attrs, i);
1275 static void remove_notes_attrs(struct module *mod)
1277 if (mod->notes_attrs)
1278 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1283 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1284 char *sectstrings, Elf_Shdr *sechdrs)
1288 static inline void remove_sect_attrs(struct module *mod)
1292 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1293 char *sectstrings, Elf_Shdr *sechdrs)
1297 static inline void remove_notes_attrs(struct module *mod)
1303 static void add_usage_links(struct module *mod)
1305 #ifdef CONFIG_MODULE_UNLOAD
1306 struct module_use *use;
1309 list_for_each_entry(use, &mod->target_list, target_list) {
1310 nowarn = sysfs_create_link(use->target->holders_dir,
1311 &mod->mkobj.kobj, mod->name);
1316 static void del_usage_links(struct module *mod)
1318 #ifdef CONFIG_MODULE_UNLOAD
1319 struct module_use *use;
1321 list_for_each_entry(use, &mod->target_list, target_list)
1322 sysfs_remove_link(use->target->holders_dir, mod->name);
1326 static int module_add_modinfo_attrs(struct module *mod)
1328 struct module_attribute *attr;
1329 struct module_attribute *temp_attr;
1333 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1334 (ARRAY_SIZE(modinfo_attrs) + 1)),
1336 if (!mod->modinfo_attrs)
1339 temp_attr = mod->modinfo_attrs;
1340 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1342 (attr->test && attr->test(mod))) {
1343 memcpy(temp_attr, attr, sizeof(*temp_attr));
1344 sysfs_attr_init(&temp_attr->attr);
1345 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1352 static void module_remove_modinfo_attrs(struct module *mod)
1354 struct module_attribute *attr;
1357 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1358 /* pick a field to test for end of list */
1359 if (!attr->attr.name)
1361 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1365 kfree(mod->modinfo_attrs);
1368 static int mod_sysfs_init(struct module *mod)
1371 struct kobject *kobj;
1373 if (!module_sysfs_initialized) {
1374 printk(KERN_ERR "%s: module sysfs not initialized\n",
1380 kobj = kset_find_obj(module_kset, mod->name);
1382 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1388 mod->mkobj.mod = mod;
1390 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1391 mod->mkobj.kobj.kset = module_kset;
1392 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1395 kobject_put(&mod->mkobj.kobj);
1397 /* delay uevent until full sysfs population */
1402 static int mod_sysfs_setup(struct module *mod,
1403 struct kernel_param *kparam,
1404 unsigned int num_params)
1408 err = mod_sysfs_init(mod);
1412 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1413 if (!mod->holders_dir) {
1418 err = module_param_sysfs_setup(mod, kparam, num_params);
1420 goto out_unreg_holders;
1422 err = module_add_modinfo_attrs(mod);
1424 goto out_unreg_param;
1426 add_usage_links(mod);
1428 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1432 module_param_sysfs_remove(mod);
1434 kobject_put(mod->holders_dir);
1436 kobject_put(&mod->mkobj.kobj);
1441 static void mod_sysfs_fini(struct module *mod)
1443 kobject_put(&mod->mkobj.kobj);
1446 #else /* CONFIG_SYSFS */
1448 static inline int mod_sysfs_init(struct module *mod)
1453 static inline int mod_sysfs_setup(struct module *mod,
1454 struct kernel_param *kparam,
1455 unsigned int num_params)
1460 static inline int module_add_modinfo_attrs(struct module *mod)
1465 static inline void module_remove_modinfo_attrs(struct module *mod)
1469 static void mod_sysfs_fini(struct module *mod)
1473 static void del_usage_links(struct module *mod)
1477 #endif /* CONFIG_SYSFS */
1479 static void mod_kobject_remove(struct module *mod)
1481 del_usage_links(mod);
1482 module_remove_modinfo_attrs(mod);
1483 module_param_sysfs_remove(mod);
1484 kobject_put(mod->mkobj.drivers_dir);
1485 kobject_put(mod->holders_dir);
1486 mod_sysfs_fini(mod);
1490 * unlink the module with the whole machine is stopped with interrupts off
1491 * - this defends against kallsyms not taking locks
1493 static int __unlink_module(void *_mod)
1495 struct module *mod = _mod;
1496 list_del(&mod->list);
1500 /* Free a module, remove from lists, etc (must hold module_mutex). */
1501 static void free_module(struct module *mod)
1503 trace_module_free(mod);
1505 /* Delete from various lists */
1506 stop_machine(__unlink_module, mod, NULL);
1507 remove_notes_attrs(mod);
1508 remove_sect_attrs(mod);
1509 mod_kobject_remove(mod);
1511 /* Arch-specific cleanup. */
1512 module_arch_cleanup(mod);
1514 /* Module unload stuff */
1515 module_unload_free(mod);
1517 /* Free any allocated parameters. */
1518 destroy_params(mod->kp, mod->num_kp);
1520 /* This may be NULL, but that's OK */
1521 module_free(mod, mod->module_init);
1523 percpu_modfree(mod);
1524 #if defined(CONFIG_MODULE_UNLOAD)
1526 free_percpu(mod->refptr);
1528 /* Free lock-classes: */
1529 lockdep_free_key_range(mod->module_core, mod->core_size);
1531 /* Finally, free the core (containing the module structure) */
1532 module_free(mod, mod->module_core);
1535 update_protections(current->mm);
1539 void *__symbol_get(const char *symbol)
1541 struct module *owner;
1542 const struct kernel_symbol *sym;
1545 sym = find_symbol(symbol, &owner, NULL, true, true);
1546 if (sym && strong_try_module_get(owner))
1550 return sym ? (void *)sym->value : NULL;
1552 EXPORT_SYMBOL_GPL(__symbol_get);
1555 * Ensure that an exported symbol [global namespace] does not already exist
1556 * in the kernel or in some other module's exported symbol table.
1558 static int verify_export_symbols(struct module *mod)
1561 struct module *owner;
1562 const struct kernel_symbol *s;
1564 const struct kernel_symbol *sym;
1567 { mod->syms, mod->num_syms },
1568 { mod->gpl_syms, mod->num_gpl_syms },
1569 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1570 #ifdef CONFIG_UNUSED_SYMBOLS
1571 { mod->unused_syms, mod->num_unused_syms },
1572 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1576 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1577 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1578 if (find_symbol(s->name, &owner, NULL, true, false)) {
1580 "%s: exports duplicate symbol %s"
1582 mod->name, s->name, module_name(owner));
1590 /* Change all symbols so that st_value encodes the pointer directly. */
1591 static int simplify_symbols(Elf_Shdr *sechdrs,
1592 unsigned int symindex,
1594 unsigned int versindex,
1595 unsigned int pcpuindex,
1598 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1599 unsigned long secbase;
1600 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1602 const struct kernel_symbol *ksym;
1604 for (i = 1; i < n; i++) {
1605 switch (sym[i].st_shndx) {
1607 /* We compiled with -fno-common. These are not
1608 supposed to happen. */
1609 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1610 printk("%s: please compile with -fno-common\n",
1616 /* Don't need to do anything */
1617 DEBUGP("Absolute symbol: 0x%08lx\n",
1618 (long)sym[i].st_value);
1622 ksym = resolve_symbol(sechdrs, versindex,
1623 strtab + sym[i].st_name, mod);
1624 /* Ok if resolved. */
1626 sym[i].st_value = ksym->value;
1631 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1634 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1635 mod->name, strtab + sym[i].st_name);
1640 /* Divert to percpu allocation if a percpu var. */
1641 if (sym[i].st_shndx == pcpuindex)
1642 secbase = (unsigned long)mod_percpu(mod);
1644 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1645 sym[i].st_value += secbase;
1653 /* Additional bytes needed by arch in front of individual sections */
1654 unsigned int __weak arch_mod_section_prepend(struct module *mod,
1655 unsigned int section)
1657 /* default implementation just returns zero */
1661 /* Update size with this section: return offset. */
1662 static long get_offset(struct module *mod, unsigned int *size,
1663 Elf_Shdr *sechdr, unsigned int section)
1667 *size += arch_mod_section_prepend(mod, section);
1668 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1669 *size = ret + sechdr->sh_size;
1673 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1674 might -- code, read-only data, read-write data, small data. Tally
1675 sizes, and place the offsets into sh_entsize fields: high bit means it
1677 static void layout_sections(struct module *mod,
1678 const Elf_Ehdr *hdr,
1680 const char *secstrings)
1682 static unsigned long const masks[][2] = {
1683 /* NOTE: all executable code must be the first section
1684 * in this array; otherwise modify the text_size
1685 * finder in the two loops below */
1686 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1687 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1688 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1689 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1693 for (i = 0; i < hdr->e_shnum; i++)
1694 sechdrs[i].sh_entsize = ~0UL;
1696 DEBUGP("Core section allocation order:\n");
1697 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1698 for (i = 0; i < hdr->e_shnum; ++i) {
1699 Elf_Shdr *s = &sechdrs[i];
1701 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1702 || (s->sh_flags & masks[m][1])
1703 || s->sh_entsize != ~0UL
1704 || strstarts(secstrings + s->sh_name, ".init"))
1706 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1707 DEBUGP("\t%s\n", secstrings + s->sh_name);
1710 mod->core_text_size = mod->core_size;
1713 DEBUGP("Init section allocation order:\n");
1714 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1715 for (i = 0; i < hdr->e_shnum; ++i) {
1716 Elf_Shdr *s = &sechdrs[i];
1718 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1719 || (s->sh_flags & masks[m][1])
1720 || s->sh_entsize != ~0UL
1721 || !strstarts(secstrings + s->sh_name, ".init"))
1723 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1724 | INIT_OFFSET_MASK);
1725 DEBUGP("\t%s\n", secstrings + s->sh_name);
1728 mod->init_text_size = mod->init_size;
1732 static void set_license(struct module *mod, const char *license)
1735 license = "unspecified";
1737 if (!license_is_gpl_compatible(license)) {
1738 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1739 printk(KERN_WARNING "%s: module license '%s' taints "
1740 "kernel.\n", mod->name, license);
1741 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1745 /* Parse tag=value strings from .modinfo section */
1746 static char *next_string(char *string, unsigned long *secsize)
1748 /* Skip non-zero chars */
1751 if ((*secsize)-- <= 1)
1755 /* Skip any zero padding. */
1756 while (!string[0]) {
1758 if ((*secsize)-- <= 1)
1764 static char *get_modinfo(Elf_Shdr *sechdrs,
1769 unsigned int taglen = strlen(tag);
1770 unsigned long size = sechdrs[info].sh_size;
1772 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1773 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1774 return p + taglen + 1;
1779 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1780 unsigned int infoindex)
1782 struct module_attribute *attr;
1785 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1788 get_modinfo(sechdrs,
1794 static void free_modinfo(struct module *mod)
1796 struct module_attribute *attr;
1799 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1805 #ifdef CONFIG_KALLSYMS
1807 /* lookup symbol in given range of kernel_symbols */
1808 static const struct kernel_symbol *lookup_symbol(const char *name,
1809 const struct kernel_symbol *start,
1810 const struct kernel_symbol *stop)
1812 const struct kernel_symbol *ks = start;
1813 for (; ks < stop; ks++)
1814 if (strcmp(ks->name, name) == 0)
1819 static int is_exported(const char *name, unsigned long value,
1820 const struct module *mod)
1822 const struct kernel_symbol *ks;
1824 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1826 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1827 return ks != NULL && ks->value == value;
1831 static char elf_type(const Elf_Sym *sym,
1833 const char *secstrings,
1836 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1837 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1842 if (sym->st_shndx == SHN_UNDEF)
1844 if (sym->st_shndx == SHN_ABS)
1846 if (sym->st_shndx >= SHN_LORESERVE)
1848 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1850 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1851 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1852 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1854 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1859 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1860 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1865 if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug"))
1870 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1873 const Elf_Shdr *sec;
1875 if (src->st_shndx == SHN_UNDEF
1876 || src->st_shndx >= shnum
1880 sec = sechdrs + src->st_shndx;
1881 if (!(sec->sh_flags & SHF_ALLOC)
1882 #ifndef CONFIG_KALLSYMS_ALL
1883 || !(sec->sh_flags & SHF_EXECINSTR)
1885 || (sec->sh_entsize & INIT_OFFSET_MASK))
1891 static unsigned long layout_symtab(struct module *mod,
1893 unsigned int symindex,
1894 unsigned int strindex,
1895 const Elf_Ehdr *hdr,
1896 const char *secstrings,
1897 unsigned long *pstroffs,
1898 unsigned long *strmap)
1900 unsigned long symoffs;
1901 Elf_Shdr *symsect = sechdrs + symindex;
1902 Elf_Shdr *strsect = sechdrs + strindex;
1905 unsigned int i, nsrc, ndst;
1907 /* Put symbol section at end of init part of module. */
1908 symsect->sh_flags |= SHF_ALLOC;
1909 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1910 symindex) | INIT_OFFSET_MASK;
1911 DEBUGP("\t%s\n", secstrings + symsect->sh_name);
1913 src = (void *)hdr + symsect->sh_offset;
1914 nsrc = symsect->sh_size / sizeof(*src);
1915 strtab = (void *)hdr + strsect->sh_offset;
1916 for (ndst = i = 1; i < nsrc; ++i, ++src)
1917 if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
1918 unsigned int j = src->st_name;
1920 while(!__test_and_set_bit(j, strmap) && strtab[j])
1925 /* Append room for core symbols at end of core part. */
1926 symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
1927 mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
1929 /* Put string table section at end of init part of module. */
1930 strsect->sh_flags |= SHF_ALLOC;
1931 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
1932 strindex) | INIT_OFFSET_MASK;
1933 DEBUGP("\t%s\n", secstrings + strsect->sh_name);
1935 /* Append room for core symbols' strings at end of core part. */
1936 *pstroffs = mod->core_size;
1937 __set_bit(0, strmap);
1938 mod->core_size += bitmap_weight(strmap, strsect->sh_size);
1943 static void add_kallsyms(struct module *mod,
1946 unsigned int symindex,
1947 unsigned int strindex,
1948 unsigned long symoffs,
1949 unsigned long stroffs,
1950 const char *secstrings,
1951 unsigned long *strmap)
1953 unsigned int i, ndst;
1958 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1959 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1960 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1962 /* Set types up while we still have access to sections. */
1963 for (i = 0; i < mod->num_symtab; i++)
1964 mod->symtab[i].st_info
1965 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1967 mod->core_symtab = dst = mod->module_core + symoffs;
1970 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
1971 if (!is_core_symbol(src, sechdrs, shnum))
1974 dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
1977 mod->core_num_syms = ndst;
1979 mod->core_strtab = s = mod->module_core + stroffs;
1980 for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i)
1981 if (test_bit(i, strmap))
1982 *++s = mod->strtab[i];
1985 static inline unsigned long layout_symtab(struct module *mod,
1987 unsigned int symindex,
1988 unsigned int strindex,
1989 const Elf_Ehdr *hdr,
1990 const char *secstrings,
1991 unsigned long *pstroffs,
1992 unsigned long *strmap)
1997 static inline void add_kallsyms(struct module *mod,
2000 unsigned int symindex,
2001 unsigned int strindex,
2002 unsigned long symoffs,
2003 unsigned long stroffs,
2004 const char *secstrings,
2005 const unsigned long *strmap)
2008 #endif /* CONFIG_KALLSYMS */
2010 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2012 #ifdef CONFIG_DYNAMIC_DEBUG
2013 if (ddebug_add_module(debug, num, debug->modname))
2014 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2019 static void *module_alloc_update_bounds(unsigned long size)
2021 void *ret = module_alloc(size);
2024 /* Update module bounds. */
2025 if ((unsigned long)ret < module_addr_min)
2026 module_addr_min = (unsigned long)ret;
2027 if ((unsigned long)ret + size > module_addr_max)
2028 module_addr_max = (unsigned long)ret + size;
2033 #ifdef CONFIG_DEBUG_KMEMLEAK
2034 static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2035 Elf_Shdr *sechdrs, char *secstrings)
2039 /* only scan the sections containing data */
2040 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2042 for (i = 1; i < hdr->e_shnum; i++) {
2043 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2045 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
2046 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
2049 kmemleak_scan_area((void *)sechdrs[i].sh_addr,
2050 sechdrs[i].sh_size, GFP_KERNEL);
2054 static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2055 Elf_Shdr *sechdrs, char *secstrings)
2060 /* Allocate and load the module: note that size of section 0 is always
2061 zero, and we rely on this for optional sections. */
2062 static noinline struct module *load_module(void __user *umod,
2064 const char __user *uargs)
2068 char *secstrings, *args, *modmagic, *strtab = NULL;
2071 unsigned int symindex = 0;
2072 unsigned int strindex = 0;
2073 unsigned int modindex, versindex, infoindex, pcpuindex;
2076 void *ptr = NULL; /* Stops spurious gcc warning */
2077 unsigned long symoffs, stroffs, *strmap;
2078 void __percpu *percpu;
2080 mm_segment_t old_fs;
2082 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2084 if (len < sizeof(*hdr))
2085 return ERR_PTR(-ENOEXEC);
2087 /* Suck in entire file: we'll want most of it. */
2088 /* vmalloc barfs on "unusual" numbers. Check here */
2089 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
2090 return ERR_PTR(-ENOMEM);
2092 if (copy_from_user(hdr, umod, len) != 0) {
2097 /* Sanity checks against insmoding binaries or wrong arch,
2098 weird elf version */
2099 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
2100 || hdr->e_type != ET_REL
2101 || !elf_check_arch(hdr)
2102 || hdr->e_shentsize != sizeof(*sechdrs)) {
2107 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
2110 /* Convenience variables */
2111 sechdrs = (void *)hdr + hdr->e_shoff;
2112 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
2113 sechdrs[0].sh_addr = 0;
2115 for (i = 1; i < hdr->e_shnum; i++) {
2116 if (sechdrs[i].sh_type != SHT_NOBITS
2117 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
2120 /* Mark all sections sh_addr with their address in the
2122 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
2124 /* Internal symbols and strings. */
2125 if (sechdrs[i].sh_type == SHT_SYMTAB) {
2127 strindex = sechdrs[i].sh_link;
2128 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
2130 #ifndef CONFIG_MODULE_UNLOAD
2131 /* Don't load .exit sections */
2132 if (strstarts(secstrings+sechdrs[i].sh_name, ".exit"))
2133 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
2137 modindex = find_sec(hdr, sechdrs, secstrings,
2138 ".gnu.linkonce.this_module");
2140 printk(KERN_WARNING "No module found in object\n");
2144 /* This is temporary: point mod into copy of data. */
2145 mod = (void *)sechdrs[modindex].sh_addr;
2147 if (symindex == 0) {
2148 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2154 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
2155 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
2156 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
2158 /* Don't keep modinfo and version sections. */
2159 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2160 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2162 /* Check module struct version now, before we try to use module. */
2163 if (!check_modstruct_version(sechdrs, versindex, mod)) {
2168 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2169 /* This is allowed: modprobe --force will invalidate it. */
2171 err = try_to_force_load(mod, "bad vermagic");
2174 } else if (!same_magic(modmagic, vermagic, versindex)) {
2175 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2176 mod->name, modmagic, vermagic);
2181 staging = get_modinfo(sechdrs, infoindex, "staging");
2183 add_taint_module(mod, TAINT_CRAP);
2184 printk(KERN_WARNING "%s: module is from the staging directory,"
2185 " the quality is unknown, you have been warned.\n",
2189 /* Now copy in args */
2190 args = strndup_user(uargs, ~0UL >> 1);
2192 err = PTR_ERR(args);
2196 strmap = kzalloc(BITS_TO_LONGS(sechdrs[strindex].sh_size)
2197 * sizeof(long), GFP_KERNEL);
2203 if (find_module(mod->name)) {
2208 mod->state = MODULE_STATE_COMING;
2210 /* Allow arches to frob section contents and sizes. */
2211 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
2216 /* We have a special allocation for this section. */
2217 err = percpu_modalloc(mod, sechdrs[pcpuindex].sh_size,
2218 sechdrs[pcpuindex].sh_addralign);
2221 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2223 /* Keep this around for failure path. */
2224 percpu = mod_percpu(mod);
2226 /* Determine total sizes, and put offsets in sh_entsize. For now
2227 this is done generically; there doesn't appear to be any
2228 special cases for the architectures. */
2229 layout_sections(mod, hdr, sechdrs, secstrings);
2230 symoffs = layout_symtab(mod, sechdrs, symindex, strindex, hdr,
2231 secstrings, &stroffs, strmap);
2233 /* Do the allocs. */
2234 ptr = module_alloc_update_bounds(mod->core_size);
2236 * The pointer to this block is stored in the module structure
2237 * which is inside the block. Just mark it as not being a
2240 kmemleak_not_leak(ptr);
2245 memset(ptr, 0, mod->core_size);
2246 mod->module_core = ptr;
2248 ptr = module_alloc_update_bounds(mod->init_size);
2250 * The pointer to this block is stored in the module structure
2251 * which is inside the block. This block doesn't need to be
2252 * scanned as it contains data and code that will be freed
2253 * after the module is initialized.
2255 kmemleak_ignore(ptr);
2256 if (!ptr && mod->init_size) {
2260 memset(ptr, 0, mod->init_size);
2261 mod->module_init = ptr;
2263 /* Transfer each section which specifies SHF_ALLOC */
2264 DEBUGP("final section addresses:\n");
2265 for (i = 0; i < hdr->e_shnum; i++) {
2268 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2271 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2272 dest = mod->module_init
2273 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2275 dest = mod->module_core + sechdrs[i].sh_entsize;
2277 if (sechdrs[i].sh_type != SHT_NOBITS)
2278 memcpy(dest, (void *)sechdrs[i].sh_addr,
2279 sechdrs[i].sh_size);
2280 /* Update sh_addr to point to copy in image. */
2281 sechdrs[i].sh_addr = (unsigned long)dest;
2282 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2284 /* Module has been moved. */
2285 mod = (void *)sechdrs[modindex].sh_addr;
2286 kmemleak_load_module(mod, hdr, sechdrs, secstrings);
2288 #if defined(CONFIG_MODULE_UNLOAD)
2289 mod->refptr = alloc_percpu(struct module_ref);
2295 /* Now we've moved module, initialize linked lists, etc. */
2296 module_unload_init(mod);
2298 /* Set up license info based on the info section */
2299 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2302 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2303 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2304 * using GPL-only symbols it needs.
2306 if (strcmp(mod->name, "ndiswrapper") == 0)
2307 add_taint(TAINT_PROPRIETARY_MODULE);
2309 /* driverloader was caught wrongly pretending to be under GPL */
2310 if (strcmp(mod->name, "driverloader") == 0)
2311 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2313 /* Set up MODINFO_ATTR fields */
2314 setup_modinfo(mod, sechdrs, infoindex);
2316 /* Fix up syms, so that st_value is a pointer to location. */
2317 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2322 /* Now we've got everything in the final locations, we can
2323 * find optional sections. */
2324 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2325 sizeof(*mod->kp), &mod->num_kp);
2326 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2327 sizeof(*mod->syms), &mod->num_syms);
2328 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2329 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2330 sizeof(*mod->gpl_syms),
2331 &mod->num_gpl_syms);
2332 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2333 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2334 "__ksymtab_gpl_future",
2335 sizeof(*mod->gpl_future_syms),
2336 &mod->num_gpl_future_syms);
2337 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2338 "__kcrctab_gpl_future");
2340 #ifdef CONFIG_UNUSED_SYMBOLS
2341 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2343 sizeof(*mod->unused_syms),
2344 &mod->num_unused_syms);
2345 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2346 "__kcrctab_unused");
2347 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2348 "__ksymtab_unused_gpl",
2349 sizeof(*mod->unused_gpl_syms),
2350 &mod->num_unused_gpl_syms);
2351 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2352 "__kcrctab_unused_gpl");
2354 #ifdef CONFIG_CONSTRUCTORS
2355 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2356 sizeof(*mod->ctors), &mod->num_ctors);
2359 #ifdef CONFIG_TRACEPOINTS
2360 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2362 sizeof(*mod->tracepoints),
2363 &mod->num_tracepoints);
2365 #ifdef CONFIG_EVENT_TRACING
2366 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2368 sizeof(*mod->trace_events),
2369 &mod->num_trace_events);
2371 * This section contains pointers to allocated objects in the trace
2372 * code and not scanning it leads to false positives.
2374 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2375 mod->num_trace_events, GFP_KERNEL);
2377 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2378 /* sechdrs[0].sh_size is always zero */
2379 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2381 sizeof(*mod->ftrace_callsites),
2382 &mod->num_ftrace_callsites);
2384 #ifdef CONFIG_MODVERSIONS
2385 if ((mod->num_syms && !mod->crcs)
2386 || (mod->num_gpl_syms && !mod->gpl_crcs)
2387 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2388 #ifdef CONFIG_UNUSED_SYMBOLS
2389 || (mod->num_unused_syms && !mod->unused_crcs)
2390 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2393 err = try_to_force_load(mod,
2394 "no versions for exported symbols");
2400 /* Now do relocations. */
2401 for (i = 1; i < hdr->e_shnum; i++) {
2402 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2403 unsigned int info = sechdrs[i].sh_info;
2405 /* Not a valid relocation section? */
2406 if (info >= hdr->e_shnum)
2409 /* Don't bother with non-allocated sections */
2410 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2413 if (sechdrs[i].sh_type == SHT_REL)
2414 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2415 else if (sechdrs[i].sh_type == SHT_RELA)
2416 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2422 /* Find duplicate symbols */
2423 err = verify_export_symbols(mod);
2427 /* Set up and sort exception table */
2428 mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
2429 sizeof(*mod->extable), &mod->num_exentries);
2430 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2432 /* Finally, copy percpu area over. */
2433 percpu_modcopy(mod, (void *)sechdrs[pcpuindex].sh_addr,
2434 sechdrs[pcpuindex].sh_size);
2436 add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex,
2437 symoffs, stroffs, secstrings, strmap);
2442 struct _ddebug *debug;
2443 unsigned int num_debug;
2445 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2446 sizeof(*debug), &num_debug);
2448 dynamic_debug_setup(debug, num_debug);
2451 err = module_finalize(hdr, sechdrs, mod);
2455 /* flush the icache in correct context */
2460 * Flush the instruction cache, since we've played with text.
2461 * Do it before processing of module parameters, so the module
2462 * can provide parameter accessor functions of its own.
2464 if (mod->module_init)
2465 flush_icache_range((unsigned long)mod->module_init,
2466 (unsigned long)mod->module_init
2468 flush_icache_range((unsigned long)mod->module_core,
2469 (unsigned long)mod->module_core + mod->core_size);
2474 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2475 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2478 /* Now sew it into the lists so we can get lockdep and oops
2479 * info during argument parsing. Noone should access us, since
2480 * strong_try_module_get() will fail.
2481 * lockdep/oops can run asynchronous, so use the RCU list insertion
2482 * function to insert in a way safe to concurrent readers.
2483 * The mutex protects against concurrent writers.
2485 list_add_rcu(&mod->list, &modules);
2487 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2491 err = mod_sysfs_setup(mod, mod->kp, mod->num_kp);
2495 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2496 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2498 /* Get rid of temporary copy */
2501 trace_module_load(mod);
2507 /* Unlink carefully: kallsyms could be walking list. */
2508 list_del_rcu(&mod->list);
2509 synchronize_sched();
2510 module_arch_cleanup(mod);
2513 module_unload_free(mod);
2514 #if defined(CONFIG_MODULE_UNLOAD)
2515 free_percpu(mod->refptr);
2518 module_free(mod, mod->module_init);
2520 module_free(mod, mod->module_core);
2521 /* mod will be freed with core. Don't access it beyond this line! */
2523 free_percpu(percpu);
2529 return ERR_PTR(err);
2532 printk(KERN_ERR "Module len %lu truncated\n", len);
2537 /* Call module constructors. */
2538 static void do_mod_ctors(struct module *mod)
2540 #ifdef CONFIG_CONSTRUCTORS
2543 for (i = 0; i < mod->num_ctors; i++)
2548 /* This is where the real work happens */
2549 SYSCALL_DEFINE3(init_module, void __user *, umod,
2550 unsigned long, len, const char __user *, uargs)
2555 /* Must have permission */
2556 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2559 /* Only one module load at a time, please */
2560 if (mutex_lock_interruptible(&module_mutex) != 0)
2563 /* Do all the hard work */
2564 mod = load_module(umod, len, uargs);
2566 mutex_unlock(&module_mutex);
2567 return PTR_ERR(mod);
2570 /* Drop lock so they can recurse */
2571 mutex_unlock(&module_mutex);
2573 blocking_notifier_call_chain(&module_notify_list,
2574 MODULE_STATE_COMING, mod);
2577 /* Start the module */
2578 if (mod->init != NULL)
2579 ret = do_one_initcall(mod->init);
2581 /* Init routine failed: abort. Try to protect us from
2582 buggy refcounters. */
2583 mod->state = MODULE_STATE_GOING;
2584 synchronize_sched();
2586 blocking_notifier_call_chain(&module_notify_list,
2587 MODULE_STATE_GOING, mod);
2588 mutex_lock(&module_mutex);
2590 mutex_unlock(&module_mutex);
2591 wake_up(&module_wq);
2596 "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2597 "%s: loading module anyway...\n",
2598 __func__, mod->name, ret,
2603 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2604 mod->state = MODULE_STATE_LIVE;
2605 wake_up(&module_wq);
2606 blocking_notifier_call_chain(&module_notify_list,
2607 MODULE_STATE_LIVE, mod);
2609 /* We need to finish all async code before the module init sequence is done */
2610 async_synchronize_full();
2612 mutex_lock(&module_mutex);
2613 /* Drop initial reference. */
2615 trim_init_extable(mod);
2616 #ifdef CONFIG_KALLSYMS
2617 mod->num_symtab = mod->core_num_syms;
2618 mod->symtab = mod->core_symtab;
2619 mod->strtab = mod->core_strtab;
2621 module_free(mod, mod->module_init);
2622 mod->module_init = NULL;
2624 mod->init_text_size = 0;
2625 mutex_unlock(&module_mutex);
2630 static inline int within(unsigned long addr, void *start, unsigned long size)
2632 return ((void *)addr >= start && (void *)addr < start + size);
2635 #ifdef CONFIG_KALLSYMS
2637 * This ignores the intensely annoying "mapping symbols" found
2638 * in ARM ELF files: $a, $t and $d.
2640 static inline int is_arm_mapping_symbol(const char *str)
2642 return str[0] == '$' && strchr("atd", str[1])
2643 && (str[2] == '\0' || str[2] == '.');
2646 static const char *get_ksymbol(struct module *mod,
2648 unsigned long *size,
2649 unsigned long *offset)
2651 unsigned int i, best = 0;
2652 unsigned long nextval;
2654 /* At worse, next value is at end of module */
2655 if (within_module_init(addr, mod))
2656 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2658 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2660 /* Scan for closest preceeding symbol, and next symbol. (ELF
2661 starts real symbols at 1). */
2662 for (i = 1; i < mod->num_symtab; i++) {
2663 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2666 /* We ignore unnamed symbols: they're uninformative
2667 * and inserted at a whim. */
2668 if (mod->symtab[i].st_value <= addr
2669 && mod->symtab[i].st_value > mod->symtab[best].st_value
2670 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2671 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2673 if (mod->symtab[i].st_value > addr
2674 && mod->symtab[i].st_value < nextval
2675 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2676 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2677 nextval = mod->symtab[i].st_value;
2684 *size = nextval - mod->symtab[best].st_value;
2686 *offset = addr - mod->symtab[best].st_value;
2687 return mod->strtab + mod->symtab[best].st_name;
2690 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2691 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2692 const char *module_address_lookup(unsigned long addr,
2693 unsigned long *size,
2694 unsigned long *offset,
2699 const char *ret = NULL;
2702 list_for_each_entry_rcu(mod, &modules, list) {
2703 if (within_module_init(addr, mod) ||
2704 within_module_core(addr, mod)) {
2706 *modname = mod->name;
2707 ret = get_ksymbol(mod, addr, size, offset);
2711 /* Make a copy in here where it's safe */
2713 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2720 int lookup_module_symbol_name(unsigned long addr, char *symname)
2725 list_for_each_entry_rcu(mod, &modules, list) {
2726 if (within_module_init(addr, mod) ||
2727 within_module_core(addr, mod)) {
2730 sym = get_ksymbol(mod, addr, NULL, NULL);
2733 strlcpy(symname, sym, KSYM_NAME_LEN);
2743 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2744 unsigned long *offset, char *modname, char *name)
2749 list_for_each_entry_rcu(mod, &modules, list) {
2750 if (within_module_init(addr, mod) ||
2751 within_module_core(addr, mod)) {
2754 sym = get_ksymbol(mod, addr, size, offset);
2758 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2760 strlcpy(name, sym, KSYM_NAME_LEN);
2770 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2771 char *name, char *module_name, int *exported)
2776 list_for_each_entry_rcu(mod, &modules, list) {
2777 if (symnum < mod->num_symtab) {
2778 *value = mod->symtab[symnum].st_value;
2779 *type = mod->symtab[symnum].st_info;
2780 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2782 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2783 *exported = is_exported(name, *value, mod);
2787 symnum -= mod->num_symtab;
2793 static unsigned long mod_find_symname(struct module *mod, const char *name)
2797 for (i = 0; i < mod->num_symtab; i++)
2798 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2799 mod->symtab[i].st_info != 'U')
2800 return mod->symtab[i].st_value;
2804 /* Look for this name: can be of form module:name. */
2805 unsigned long module_kallsyms_lookup_name(const char *name)
2809 unsigned long ret = 0;
2811 /* Don't lock: we're in enough trouble already. */
2813 if ((colon = strchr(name, ':')) != NULL) {
2815 if ((mod = find_module(name)) != NULL)
2816 ret = mod_find_symname(mod, colon+1);
2819 list_for_each_entry_rcu(mod, &modules, list)
2820 if ((ret = mod_find_symname(mod, name)) != 0)
2827 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
2828 struct module *, unsigned long),
2835 list_for_each_entry(mod, &modules, list) {
2836 for (i = 0; i < mod->num_symtab; i++) {
2837 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
2838 mod, mod->symtab[i].st_value);
2845 #endif /* CONFIG_KALLSYMS */
2847 static char *module_flags(struct module *mod, char *buf)
2852 mod->state == MODULE_STATE_GOING ||
2853 mod->state == MODULE_STATE_COMING) {
2855 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2857 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2859 if (mod->taints & (1 << TAINT_CRAP))
2862 * TAINT_FORCED_RMMOD: could be added.
2863 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2867 /* Show a - for module-is-being-unloaded */
2868 if (mod->state == MODULE_STATE_GOING)
2870 /* Show a + for module-is-being-loaded */
2871 if (mod->state == MODULE_STATE_COMING)
2880 #ifdef CONFIG_PROC_FS
2881 /* Called by the /proc file system to return a list of modules. */
2882 static void *m_start(struct seq_file *m, loff_t *pos)
2884 mutex_lock(&module_mutex);
2885 return seq_list_start(&modules, *pos);
2888 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2890 return seq_list_next(p, &modules, pos);
2893 static void m_stop(struct seq_file *m, void *p)
2895 mutex_unlock(&module_mutex);
2898 static int m_show(struct seq_file *m, void *p)
2900 struct module *mod = list_entry(p, struct module, list);
2903 seq_printf(m, "%s %u",
2904 mod->name, mod->init_size + mod->core_size);
2905 print_unload_info(m, mod);
2907 /* Informative for users. */
2908 seq_printf(m, " %s",
2909 mod->state == MODULE_STATE_GOING ? "Unloading":
2910 mod->state == MODULE_STATE_COMING ? "Loading":
2912 /* Used by oprofile and other similar tools. */
2913 seq_printf(m, " 0x%p", mod->module_core);
2917 seq_printf(m, " %s", module_flags(mod, buf));
2919 seq_printf(m, "\n");
2923 /* Format: modulename size refcount deps address
2925 Where refcount is a number or -, and deps is a comma-separated list
2928 static const struct seq_operations modules_op = {
2935 static int modules_open(struct inode *inode, struct file *file)
2937 return seq_open(file, &modules_op);
2940 static const struct file_operations proc_modules_operations = {
2941 .open = modules_open,
2943 .llseek = seq_lseek,
2944 .release = seq_release,
2947 static int __init proc_modules_init(void)
2949 proc_create("modules", 0, NULL, &proc_modules_operations);
2952 module_init(proc_modules_init);
2955 /* Given an address, look for it in the module exception tables. */
2956 const struct exception_table_entry *search_module_extables(unsigned long addr)
2958 const struct exception_table_entry *e = NULL;
2962 list_for_each_entry_rcu(mod, &modules, list) {
2963 if (mod->num_exentries == 0)
2966 e = search_extable(mod->extable,
2967 mod->extable + mod->num_exentries - 1,
2974 /* Now, if we found one, we are running inside it now, hence
2975 we cannot unload the module, hence no refcnt needed. */
2980 * is_module_address - is this address inside a module?
2981 * @addr: the address to check.
2983 * See is_module_text_address() if you simply want to see if the address
2984 * is code (not data).
2986 bool is_module_address(unsigned long addr)
2991 ret = __module_address(addr) != NULL;
2998 * __module_address - get the module which contains an address.
2999 * @addr: the address.
3001 * Must be called with preempt disabled or module mutex held so that
3002 * module doesn't get freed during this.
3004 struct module *__module_address(unsigned long addr)
3008 if (addr < module_addr_min || addr > module_addr_max)
3011 list_for_each_entry_rcu(mod, &modules, list)
3012 if (within_module_core(addr, mod)
3013 || within_module_init(addr, mod))
3017 EXPORT_SYMBOL_GPL(__module_address);
3020 * is_module_text_address - is this address inside module code?
3021 * @addr: the address to check.
3023 * See is_module_address() if you simply want to see if the address is
3024 * anywhere in a module. See kernel_text_address() for testing if an
3025 * address corresponds to kernel or module code.
3027 bool is_module_text_address(unsigned long addr)
3032 ret = __module_text_address(addr) != NULL;
3039 * __module_text_address - get the module whose code contains an address.
3040 * @addr: the address.
3042 * Must be called with preempt disabled or module mutex held so that
3043 * module doesn't get freed during this.
3045 struct module *__module_text_address(unsigned long addr)
3047 struct module *mod = __module_address(addr);
3049 /* Make sure it's within the text section. */
3050 if (!within(addr, mod->module_init, mod->init_text_size)
3051 && !within(addr, mod->module_core, mod->core_text_size))
3056 EXPORT_SYMBOL_GPL(__module_text_address);
3058 /* Don't grab lock, we're oopsing. */
3059 void print_modules(void)
3064 printk(KERN_DEFAULT "Modules linked in:");
3065 /* Most callers should already have preempt disabled, but make sure */
3067 list_for_each_entry_rcu(mod, &modules, list)
3068 printk(" %s%s", mod->name, module_flags(mod, buf));
3070 if (last_unloaded_module[0])
3071 printk(" [last unloaded: %s]", last_unloaded_module);
3075 #ifdef CONFIG_MODVERSIONS
3076 /* Generate the signature for all relevant module structures here.
3077 * If these change, we don't want to try to parse the module. */
3078 void module_layout(struct module *mod,
3079 struct modversion_info *ver,
3080 struct kernel_param *kp,
3081 struct kernel_symbol *ks,
3082 struct tracepoint *tp)
3085 EXPORT_SYMBOL(module_layout);
3088 #ifdef CONFIG_TRACEPOINTS
3089 void module_update_tracepoints(void)
3093 mutex_lock(&module_mutex);
3094 list_for_each_entry(mod, &modules, list)
3096 tracepoint_update_probe_range(mod->tracepoints,
3097 mod->tracepoints + mod->num_tracepoints);
3098 mutex_unlock(&module_mutex);
3102 * Returns 0 if current not found.
3103 * Returns 1 if current found.
3105 int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3107 struct module *iter_mod;
3110 mutex_lock(&module_mutex);
3111 list_for_each_entry(iter_mod, &modules, list) {
3112 if (!iter_mod->taints) {
3114 * Sorted module list
3116 if (iter_mod < iter->module)
3118 else if (iter_mod > iter->module)
3119 iter->tracepoint = NULL;
3120 found = tracepoint_get_iter_range(&iter->tracepoint,
3121 iter_mod->tracepoints,
3122 iter_mod->tracepoints
3123 + iter_mod->num_tracepoints);
3125 iter->module = iter_mod;
3130 mutex_unlock(&module_mutex);