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))
77 * 1) List of modules (also safely readable with preempt_disable),
78 * 2) module_use links,
79 * 3) module_addr_min/module_addr_max.
80 * (delete uses stop_machine/add uses RCU list operations). */
81 DEFINE_MUTEX(module_mutex);
82 EXPORT_SYMBOL_GPL(module_mutex);
83 static LIST_HEAD(modules);
84 #ifdef CONFIG_KGDB_KDB
85 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
86 #endif /* CONFIG_KGDB_KDB */
89 /* Block module loading/unloading? */
90 int modules_disabled = 0;
92 /* Waiting for a module to finish initializing? */
93 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
95 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
97 /* Bounds of module allocation, for speeding __module_address.
98 * Protected by module_mutex. */
99 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
101 int register_module_notifier(struct notifier_block * nb)
103 return blocking_notifier_chain_register(&module_notify_list, nb);
105 EXPORT_SYMBOL(register_module_notifier);
107 int unregister_module_notifier(struct notifier_block * nb)
109 return blocking_notifier_chain_unregister(&module_notify_list, nb);
111 EXPORT_SYMBOL(unregister_module_notifier);
113 /* We require a truly strong try_module_get(): 0 means failure due to
114 ongoing or failed initialization etc. */
115 static inline int strong_try_module_get(struct module *mod)
117 if (mod && mod->state == MODULE_STATE_COMING)
119 if (try_module_get(mod))
125 static inline void add_taint_module(struct module *mod, unsigned flag)
128 mod->taints |= (1U << flag);
132 * A thread that wants to hold a reference to a module only while it
133 * is running can call this to safely exit. nfsd and lockd use this.
135 void __module_put_and_exit(struct module *mod, long code)
140 EXPORT_SYMBOL(__module_put_and_exit);
142 /* Find a module section: 0 means not found. */
143 static unsigned int find_sec(Elf_Ehdr *hdr,
145 const char *secstrings,
150 for (i = 1; i < hdr->e_shnum; i++)
151 /* Alloc bit cleared means "ignore it." */
152 if ((sechdrs[i].sh_flags & SHF_ALLOC)
153 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
158 /* Find a module section, or NULL. */
159 static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
160 const char *secstrings, const char *name)
162 /* Section 0 has sh_addr 0. */
163 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
166 /* Find a module section, or NULL. Fill in number of "objects" in section. */
167 static void *section_objs(Elf_Ehdr *hdr,
169 const char *secstrings,
174 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
176 /* Section 0 has sh_addr 0 and sh_size 0. */
177 *num = sechdrs[sec].sh_size / object_size;
178 return (void *)sechdrs[sec].sh_addr;
181 /* Provided by the linker */
182 extern const struct kernel_symbol __start___ksymtab[];
183 extern const struct kernel_symbol __stop___ksymtab[];
184 extern const struct kernel_symbol __start___ksymtab_gpl[];
185 extern const struct kernel_symbol __stop___ksymtab_gpl[];
186 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
187 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
188 extern const unsigned long __start___kcrctab[];
189 extern const unsigned long __start___kcrctab_gpl[];
190 extern const unsigned long __start___kcrctab_gpl_future[];
191 #ifdef CONFIG_UNUSED_SYMBOLS
192 extern const struct kernel_symbol __start___ksymtab_unused[];
193 extern const struct kernel_symbol __stop___ksymtab_unused[];
194 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
195 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
196 extern const unsigned long __start___kcrctab_unused[];
197 extern const unsigned long __start___kcrctab_unused_gpl[];
200 #ifndef CONFIG_MODVERSIONS
201 #define symversion(base, idx) NULL
203 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
206 static bool each_symbol_in_section(const struct symsearch *arr,
207 unsigned int arrsize,
208 struct module *owner,
209 bool (*fn)(const struct symsearch *syms,
210 struct module *owner,
211 unsigned int symnum, void *data),
216 for (j = 0; j < arrsize; j++) {
217 for (i = 0; i < arr[j].stop - arr[j].start; i++)
218 if (fn(&arr[j], owner, i, data))
225 /* Returns true as soon as fn returns true, otherwise false. */
226 bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
227 unsigned int symnum, void *data), void *data)
230 const struct symsearch arr[] = {
231 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
232 NOT_GPL_ONLY, false },
233 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
234 __start___kcrctab_gpl,
236 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
237 __start___kcrctab_gpl_future,
238 WILL_BE_GPL_ONLY, false },
239 #ifdef CONFIG_UNUSED_SYMBOLS
240 { __start___ksymtab_unused, __stop___ksymtab_unused,
241 __start___kcrctab_unused,
242 NOT_GPL_ONLY, true },
243 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
244 __start___kcrctab_unused_gpl,
249 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
252 list_for_each_entry_rcu(mod, &modules, list) {
253 struct symsearch arr[] = {
254 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
255 NOT_GPL_ONLY, false },
256 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
259 { mod->gpl_future_syms,
260 mod->gpl_future_syms + mod->num_gpl_future_syms,
261 mod->gpl_future_crcs,
262 WILL_BE_GPL_ONLY, false },
263 #ifdef CONFIG_UNUSED_SYMBOLS
265 mod->unused_syms + mod->num_unused_syms,
267 NOT_GPL_ONLY, true },
268 { mod->unused_gpl_syms,
269 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
270 mod->unused_gpl_crcs,
275 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
280 EXPORT_SYMBOL_GPL(each_symbol);
282 struct find_symbol_arg {
289 struct module *owner;
290 const unsigned long *crc;
291 const struct kernel_symbol *sym;
294 static bool find_symbol_in_section(const struct symsearch *syms,
295 struct module *owner,
296 unsigned int symnum, void *data)
298 struct find_symbol_arg *fsa = data;
300 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
304 if (syms->licence == GPL_ONLY)
306 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
307 printk(KERN_WARNING "Symbol %s is being used "
308 "by a non-GPL module, which will not "
309 "be allowed in the future\n", fsa->name);
310 printk(KERN_WARNING "Please see the file "
311 "Documentation/feature-removal-schedule.txt "
312 "in the kernel source tree for more details.\n");
316 #ifdef CONFIG_UNUSED_SYMBOLS
317 if (syms->unused && fsa->warn) {
318 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
319 "however this module is using it.\n", fsa->name);
321 "This symbol will go away in the future.\n");
323 "Please evalute if this is the right api to use and if "
324 "it really is, submit a report the linux kernel "
325 "mailinglist together with submitting your code for "
331 fsa->crc = symversion(syms->crcs, symnum);
332 fsa->sym = &syms->start[symnum];
336 /* Find a symbol and return it, along with, (optional) crc and
337 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
338 const struct kernel_symbol *find_symbol(const char *name,
339 struct module **owner,
340 const unsigned long **crc,
344 struct find_symbol_arg fsa;
350 if (each_symbol(find_symbol_in_section, &fsa)) {
358 DEBUGP("Failed to find symbol %s\n", name);
361 EXPORT_SYMBOL_GPL(find_symbol);
363 /* Search for module by name: must hold module_mutex. */
364 struct module *find_module(const char *name)
368 list_for_each_entry(mod, &modules, list) {
369 if (strcmp(mod->name, name) == 0)
374 EXPORT_SYMBOL_GPL(find_module);
378 static inline void __percpu *mod_percpu(struct module *mod)
383 static int percpu_modalloc(struct module *mod,
384 unsigned long size, unsigned long align)
386 if (align > PAGE_SIZE) {
387 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
388 mod->name, align, PAGE_SIZE);
392 mod->percpu = __alloc_reserved_percpu(size, align);
395 "Could not allocate %lu bytes percpu data\n", size);
398 mod->percpu_size = size;
402 static void percpu_modfree(struct module *mod)
404 free_percpu(mod->percpu);
407 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
409 const char *secstrings)
411 return find_sec(hdr, sechdrs, secstrings, ".data..percpu");
414 static void percpu_modcopy(struct module *mod,
415 const void *from, unsigned long size)
419 for_each_possible_cpu(cpu)
420 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
424 * is_module_percpu_address - test whether address is from module static percpu
425 * @addr: address to test
427 * Test whether @addr belongs to module static percpu area.
430 * %true if @addr is from module static percpu area
432 bool is_module_percpu_address(unsigned long addr)
439 list_for_each_entry_rcu(mod, &modules, list) {
440 if (!mod->percpu_size)
442 for_each_possible_cpu(cpu) {
443 void *start = per_cpu_ptr(mod->percpu, cpu);
445 if ((void *)addr >= start &&
446 (void *)addr < start + mod->percpu_size) {
457 #else /* ... !CONFIG_SMP */
459 static inline void __percpu *mod_percpu(struct module *mod)
463 static inline int percpu_modalloc(struct module *mod,
464 unsigned long size, unsigned long align)
468 static inline void percpu_modfree(struct module *mod)
471 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
473 const char *secstrings)
477 static inline void percpu_modcopy(struct module *mod,
478 const void *from, unsigned long size)
480 /* pcpusec should be 0, and size of that section should be 0. */
483 bool is_module_percpu_address(unsigned long addr)
488 #endif /* CONFIG_SMP */
490 #define MODINFO_ATTR(field) \
491 static void setup_modinfo_##field(struct module *mod, const char *s) \
493 mod->field = kstrdup(s, GFP_KERNEL); \
495 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
496 struct module *mod, char *buffer) \
498 return sprintf(buffer, "%s\n", mod->field); \
500 static int modinfo_##field##_exists(struct module *mod) \
502 return mod->field != NULL; \
504 static void free_modinfo_##field(struct module *mod) \
509 static struct module_attribute modinfo_##field = { \
510 .attr = { .name = __stringify(field), .mode = 0444 }, \
511 .show = show_modinfo_##field, \
512 .setup = setup_modinfo_##field, \
513 .test = modinfo_##field##_exists, \
514 .free = free_modinfo_##field, \
517 MODINFO_ATTR(version);
518 MODINFO_ATTR(srcversion);
520 static char last_unloaded_module[MODULE_NAME_LEN+1];
522 #ifdef CONFIG_MODULE_UNLOAD
524 EXPORT_TRACEPOINT_SYMBOL(module_get);
526 /* Init the unload section of the module. */
527 static void module_unload_init(struct module *mod)
529 INIT_LIST_HEAD(&mod->source_list);
530 INIT_LIST_HEAD(&mod->target_list);
532 /* Hold reference count during initialization. */
533 __this_cpu_write(mod->refptr->incs, 1);
534 /* Backwards compatibility macros put refcount during init. */
535 mod->waiter = current;
538 /* Does a already use b? */
539 static int already_uses(struct module *a, struct module *b)
541 struct module_use *use;
543 list_for_each_entry(use, &b->source_list, source_list) {
544 if (use->source == a) {
545 DEBUGP("%s uses %s!\n", a->name, b->name);
549 DEBUGP("%s does not use %s!\n", a->name, b->name);
555 * - we add 'a' as a "source", 'b' as a "target" of module use
556 * - the module_use is added to the list of 'b' sources (so
557 * 'b' can walk the list to see who sourced them), and of 'a'
558 * targets (so 'a' can see what modules it targets).
560 static int add_module_usage(struct module *a, struct module *b)
562 struct module_use *use;
564 DEBUGP("Allocating new usage for %s.\n", a->name);
565 use = kmalloc(sizeof(*use), GFP_ATOMIC);
567 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
573 list_add(&use->source_list, &b->source_list);
574 list_add(&use->target_list, &a->target_list);
578 /* Module a uses b: caller needs module_mutex() */
579 int ref_module(struct module *a, struct module *b)
583 if (b == NULL || already_uses(a, b))
586 /* If module isn't available, we fail. */
587 err = strong_try_module_get(b);
591 err = add_module_usage(a, b);
598 EXPORT_SYMBOL_GPL(ref_module);
600 /* Clear the unload stuff of the module. */
601 static void module_unload_free(struct module *mod)
603 struct module_use *use, *tmp;
605 mutex_lock(&module_mutex);
606 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
607 struct module *i = use->target;
608 DEBUGP("%s unusing %s\n", mod->name, i->name);
610 list_del(&use->source_list);
611 list_del(&use->target_list);
614 mutex_unlock(&module_mutex);
617 #ifdef CONFIG_MODULE_FORCE_UNLOAD
618 static inline int try_force_unload(unsigned int flags)
620 int ret = (flags & O_TRUNC);
622 add_taint(TAINT_FORCED_RMMOD);
626 static inline int try_force_unload(unsigned int flags)
630 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
639 /* Whole machine is stopped with interrupts off when this runs. */
640 static int __try_stop_module(void *_sref)
642 struct stopref *sref = _sref;
644 /* If it's not unused, quit unless we're forcing. */
645 if (module_refcount(sref->mod) != 0) {
646 if (!(*sref->forced = try_force_unload(sref->flags)))
650 /* Mark it as dying. */
651 sref->mod->state = MODULE_STATE_GOING;
655 static int try_stop_module(struct module *mod, int flags, int *forced)
657 if (flags & O_NONBLOCK) {
658 struct stopref sref = { mod, flags, forced };
660 return stop_machine(__try_stop_module, &sref, NULL);
662 /* We don't need to stop the machine for this. */
663 mod->state = MODULE_STATE_GOING;
669 unsigned int module_refcount(struct module *mod)
671 unsigned int incs = 0, decs = 0;
674 for_each_possible_cpu(cpu)
675 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
677 * ensure the incs are added up after the decs.
678 * module_put ensures incs are visible before decs with smp_wmb.
680 * This 2-count scheme avoids the situation where the refcount
681 * for CPU0 is read, then CPU0 increments the module refcount,
682 * then CPU1 drops that refcount, then the refcount for CPU1 is
683 * read. We would record a decrement but not its corresponding
684 * increment so we would see a low count (disaster).
686 * Rare situation? But module_refcount can be preempted, and we
687 * might be tallying up 4096+ CPUs. So it is not impossible.
690 for_each_possible_cpu(cpu)
691 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
694 EXPORT_SYMBOL(module_refcount);
696 /* This exists whether we can unload or not */
697 static void free_module(struct module *mod);
699 static void wait_for_zero_refcount(struct module *mod)
701 /* Since we might sleep for some time, release the mutex first */
702 mutex_unlock(&module_mutex);
704 DEBUGP("Looking at refcount...\n");
705 set_current_state(TASK_UNINTERRUPTIBLE);
706 if (module_refcount(mod) == 0)
710 current->state = TASK_RUNNING;
711 mutex_lock(&module_mutex);
714 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
718 char name[MODULE_NAME_LEN];
721 if (!capable(CAP_SYS_MODULE) || modules_disabled)
724 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
726 name[MODULE_NAME_LEN-1] = '\0';
728 if (mutex_lock_interruptible(&module_mutex) != 0)
731 mod = find_module(name);
737 if (!list_empty(&mod->source_list)) {
738 /* Other modules depend on us: get rid of them first. */
743 /* Doing init or already dying? */
744 if (mod->state != MODULE_STATE_LIVE) {
745 /* FIXME: if (force), slam module count and wake up
747 DEBUGP("%s already dying\n", mod->name);
752 /* If it has an init func, it must have an exit func to unload */
753 if (mod->init && !mod->exit) {
754 forced = try_force_unload(flags);
756 /* This module can't be removed */
762 /* Set this up before setting mod->state */
763 mod->waiter = current;
765 /* Stop the machine so refcounts can't move and disable module. */
766 ret = try_stop_module(mod, flags, &forced);
770 /* Never wait if forced. */
771 if (!forced && module_refcount(mod) != 0)
772 wait_for_zero_refcount(mod);
774 mutex_unlock(&module_mutex);
775 /* Final destruction now noone is using it. */
776 if (mod->exit != NULL)
778 blocking_notifier_call_chain(&module_notify_list,
779 MODULE_STATE_GOING, mod);
780 async_synchronize_full();
782 /* Store the name of the last unloaded module for diagnostic purposes */
783 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
788 mutex_unlock(&module_mutex);
792 static inline void print_unload_info(struct seq_file *m, struct module *mod)
794 struct module_use *use;
795 int printed_something = 0;
797 seq_printf(m, " %u ", module_refcount(mod));
799 /* Always include a trailing , so userspace can differentiate
800 between this and the old multi-field proc format. */
801 list_for_each_entry(use, &mod->source_list, source_list) {
802 printed_something = 1;
803 seq_printf(m, "%s,", use->source->name);
806 if (mod->init != NULL && mod->exit == NULL) {
807 printed_something = 1;
808 seq_printf(m, "[permanent],");
811 if (!printed_something)
815 void __symbol_put(const char *symbol)
817 struct module *owner;
820 if (!find_symbol(symbol, &owner, NULL, true, false))
825 EXPORT_SYMBOL(__symbol_put);
827 /* Note this assumes addr is a function, which it currently always is. */
828 void symbol_put_addr(void *addr)
830 struct module *modaddr;
831 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
833 if (core_kernel_text(a))
836 /* module_text_address is safe here: we're supposed to have reference
837 * to module from symbol_get, so it can't go away. */
838 modaddr = __module_text_address(a);
842 EXPORT_SYMBOL_GPL(symbol_put_addr);
844 static ssize_t show_refcnt(struct module_attribute *mattr,
845 struct module *mod, char *buffer)
847 return sprintf(buffer, "%u\n", module_refcount(mod));
850 static struct module_attribute refcnt = {
851 .attr = { .name = "refcnt", .mode = 0444 },
855 void module_put(struct module *module)
859 smp_wmb(); /* see comment in module_refcount */
860 __this_cpu_inc(module->refptr->decs);
862 trace_module_put(module, _RET_IP_);
863 /* Maybe they're waiting for us to drop reference? */
864 if (unlikely(!module_is_live(module)))
865 wake_up_process(module->waiter);
869 EXPORT_SYMBOL(module_put);
871 #else /* !CONFIG_MODULE_UNLOAD */
872 static inline void print_unload_info(struct seq_file *m, struct module *mod)
874 /* We don't know the usage count, or what modules are using. */
875 seq_printf(m, " - -");
878 static inline void module_unload_free(struct module *mod)
882 int ref_module(struct module *a, struct module *b)
884 return strong_try_module_get(b);
886 EXPORT_SYMBOL_GPL(ref_module);
888 static inline void module_unload_init(struct module *mod)
891 #endif /* CONFIG_MODULE_UNLOAD */
893 static ssize_t show_initstate(struct module_attribute *mattr,
894 struct module *mod, char *buffer)
896 const char *state = "unknown";
898 switch (mod->state) {
899 case MODULE_STATE_LIVE:
902 case MODULE_STATE_COMING:
905 case MODULE_STATE_GOING:
909 return sprintf(buffer, "%s\n", state);
912 static struct module_attribute initstate = {
913 .attr = { .name = "initstate", .mode = 0444 },
914 .show = show_initstate,
917 static struct module_attribute *modinfo_attrs[] = {
921 #ifdef CONFIG_MODULE_UNLOAD
927 static const char vermagic[] = VERMAGIC_STRING;
929 static int try_to_force_load(struct module *mod, const char *reason)
931 #ifdef CONFIG_MODULE_FORCE_LOAD
932 if (!test_taint(TAINT_FORCED_MODULE))
933 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
935 add_taint_module(mod, TAINT_FORCED_MODULE);
942 #ifdef CONFIG_MODVERSIONS
943 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
944 static unsigned long maybe_relocated(unsigned long crc,
945 const struct module *crc_owner)
947 #ifdef ARCH_RELOCATES_KCRCTAB
948 if (crc_owner == NULL)
949 return crc - (unsigned long)reloc_start;
954 static int check_version(Elf_Shdr *sechdrs,
955 unsigned int versindex,
958 const unsigned long *crc,
959 const struct module *crc_owner)
961 unsigned int i, num_versions;
962 struct modversion_info *versions;
964 /* Exporting module didn't supply crcs? OK, we're already tainted. */
968 /* No versions at all? modprobe --force does this. */
970 return try_to_force_load(mod, symname) == 0;
972 versions = (void *) sechdrs[versindex].sh_addr;
973 num_versions = sechdrs[versindex].sh_size
974 / sizeof(struct modversion_info);
976 for (i = 0; i < num_versions; i++) {
977 if (strcmp(versions[i].name, symname) != 0)
980 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
982 DEBUGP("Found checksum %lX vs module %lX\n",
983 maybe_relocated(*crc, crc_owner), versions[i].crc);
987 printk(KERN_WARNING "%s: no symbol version for %s\n",
992 printk("%s: disagrees about version of symbol %s\n",
997 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
998 unsigned int versindex,
1001 const unsigned long *crc;
1003 /* Since this should be found in kernel (which can't be removed),
1004 * no locking is necessary. */
1005 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1008 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1012 /* First part is kernel version, which we ignore if module has crcs. */
1013 static inline int same_magic(const char *amagic, const char *bmagic,
1017 amagic += strcspn(amagic, " ");
1018 bmagic += strcspn(bmagic, " ");
1020 return strcmp(amagic, bmagic) == 0;
1023 static inline int check_version(Elf_Shdr *sechdrs,
1024 unsigned int versindex,
1025 const char *symname,
1027 const unsigned long *crc,
1028 const struct module *crc_owner)
1033 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1034 unsigned int versindex,
1040 static inline int same_magic(const char *amagic, const char *bmagic,
1043 return strcmp(amagic, bmagic) == 0;
1045 #endif /* CONFIG_MODVERSIONS */
1047 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1048 static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
1049 unsigned int versindex,
1054 struct module *owner;
1055 const struct kernel_symbol *sym;
1056 const unsigned long *crc;
1059 mutex_lock(&module_mutex);
1060 sym = find_symbol(name, &owner, &crc,
1061 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1065 if (!check_version(sechdrs, versindex, name, mod, crc, owner)) {
1066 sym = ERR_PTR(-EINVAL);
1070 err = ref_module(mod, owner);
1077 /* We must make copy under the lock if we failed to get ref. */
1078 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1080 mutex_unlock(&module_mutex);
1084 static const struct kernel_symbol *resolve_symbol_wait(Elf_Shdr *sechdrs,
1085 unsigned int versindex,
1089 const struct kernel_symbol *ksym;
1090 char ownername[MODULE_NAME_LEN];
1092 if (wait_event_interruptible_timeout(module_wq,
1093 !IS_ERR(ksym = resolve_symbol(sechdrs, versindex, name,
1095 PTR_ERR(ksym) != -EBUSY,
1097 printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
1098 mod->name, ownername);
1104 * /sys/module/foo/sections stuff
1105 * J. Corbet <corbet@lwn.net>
1107 #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1109 static inline bool sect_empty(const Elf_Shdr *sect)
1111 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1114 struct module_sect_attr
1116 struct module_attribute mattr;
1118 unsigned long address;
1121 struct module_sect_attrs
1123 struct attribute_group grp;
1124 unsigned int nsections;
1125 struct module_sect_attr attrs[0];
1128 static ssize_t module_sect_show(struct module_attribute *mattr,
1129 struct module *mod, char *buf)
1131 struct module_sect_attr *sattr =
1132 container_of(mattr, struct module_sect_attr, mattr);
1133 return sprintf(buf, "0x%lx\n", sattr->address);
1136 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1138 unsigned int section;
1140 for (section = 0; section < sect_attrs->nsections; section++)
1141 kfree(sect_attrs->attrs[section].name);
1145 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1146 char *secstrings, Elf_Shdr *sechdrs)
1148 unsigned int nloaded = 0, i, size[2];
1149 struct module_sect_attrs *sect_attrs;
1150 struct module_sect_attr *sattr;
1151 struct attribute **gattr;
1153 /* Count loaded sections and allocate structures */
1154 for (i = 0; i < nsect; i++)
1155 if (!sect_empty(&sechdrs[i]))
1157 size[0] = ALIGN(sizeof(*sect_attrs)
1158 + nloaded * sizeof(sect_attrs->attrs[0]),
1159 sizeof(sect_attrs->grp.attrs[0]));
1160 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1161 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1162 if (sect_attrs == NULL)
1165 /* Setup section attributes. */
1166 sect_attrs->grp.name = "sections";
1167 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1169 sect_attrs->nsections = 0;
1170 sattr = §_attrs->attrs[0];
1171 gattr = §_attrs->grp.attrs[0];
1172 for (i = 0; i < nsect; i++) {
1173 if (sect_empty(&sechdrs[i]))
1175 sattr->address = sechdrs[i].sh_addr;
1176 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1178 if (sattr->name == NULL)
1180 sect_attrs->nsections++;
1181 sysfs_attr_init(&sattr->mattr.attr);
1182 sattr->mattr.show = module_sect_show;
1183 sattr->mattr.store = NULL;
1184 sattr->mattr.attr.name = sattr->name;
1185 sattr->mattr.attr.mode = S_IRUGO;
1186 *(gattr++) = &(sattr++)->mattr.attr;
1190 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1193 mod->sect_attrs = sect_attrs;
1196 free_sect_attrs(sect_attrs);
1199 static void remove_sect_attrs(struct module *mod)
1201 if (mod->sect_attrs) {
1202 sysfs_remove_group(&mod->mkobj.kobj,
1203 &mod->sect_attrs->grp);
1204 /* We are positive that no one is using any sect attrs
1205 * at this point. Deallocate immediately. */
1206 free_sect_attrs(mod->sect_attrs);
1207 mod->sect_attrs = NULL;
1212 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1215 struct module_notes_attrs {
1216 struct kobject *dir;
1218 struct bin_attribute attrs[0];
1221 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1222 struct bin_attribute *bin_attr,
1223 char *buf, loff_t pos, size_t count)
1226 * The caller checked the pos and count against our size.
1228 memcpy(buf, bin_attr->private + pos, count);
1232 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1235 if (notes_attrs->dir) {
1237 sysfs_remove_bin_file(notes_attrs->dir,
1238 ¬es_attrs->attrs[i]);
1239 kobject_put(notes_attrs->dir);
1244 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1245 char *secstrings, Elf_Shdr *sechdrs)
1247 unsigned int notes, loaded, i;
1248 struct module_notes_attrs *notes_attrs;
1249 struct bin_attribute *nattr;
1251 /* failed to create section attributes, so can't create notes */
1252 if (!mod->sect_attrs)
1255 /* Count notes sections and allocate structures. */
1257 for (i = 0; i < nsect; i++)
1258 if (!sect_empty(&sechdrs[i]) &&
1259 (sechdrs[i].sh_type == SHT_NOTE))
1265 notes_attrs = kzalloc(sizeof(*notes_attrs)
1266 + notes * sizeof(notes_attrs->attrs[0]),
1268 if (notes_attrs == NULL)
1271 notes_attrs->notes = notes;
1272 nattr = ¬es_attrs->attrs[0];
1273 for (loaded = i = 0; i < nsect; ++i) {
1274 if (sect_empty(&sechdrs[i]))
1276 if (sechdrs[i].sh_type == SHT_NOTE) {
1277 sysfs_bin_attr_init(nattr);
1278 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1279 nattr->attr.mode = S_IRUGO;
1280 nattr->size = sechdrs[i].sh_size;
1281 nattr->private = (void *) sechdrs[i].sh_addr;
1282 nattr->read = module_notes_read;
1288 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1289 if (!notes_attrs->dir)
1292 for (i = 0; i < notes; ++i)
1293 if (sysfs_create_bin_file(notes_attrs->dir,
1294 ¬es_attrs->attrs[i]))
1297 mod->notes_attrs = notes_attrs;
1301 free_notes_attrs(notes_attrs, i);
1304 static void remove_notes_attrs(struct module *mod)
1306 if (mod->notes_attrs)
1307 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1312 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1313 char *sectstrings, Elf_Shdr *sechdrs)
1317 static inline void remove_sect_attrs(struct module *mod)
1321 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1322 char *sectstrings, Elf_Shdr *sechdrs)
1326 static inline void remove_notes_attrs(struct module *mod)
1332 static void add_usage_links(struct module *mod)
1334 #ifdef CONFIG_MODULE_UNLOAD
1335 struct module_use *use;
1338 mutex_lock(&module_mutex);
1339 list_for_each_entry(use, &mod->target_list, target_list) {
1340 nowarn = sysfs_create_link(use->target->holders_dir,
1341 &mod->mkobj.kobj, mod->name);
1343 mutex_unlock(&module_mutex);
1347 static void del_usage_links(struct module *mod)
1349 #ifdef CONFIG_MODULE_UNLOAD
1350 struct module_use *use;
1352 mutex_lock(&module_mutex);
1353 list_for_each_entry(use, &mod->target_list, target_list)
1354 sysfs_remove_link(use->target->holders_dir, mod->name);
1355 mutex_unlock(&module_mutex);
1359 static int module_add_modinfo_attrs(struct module *mod)
1361 struct module_attribute *attr;
1362 struct module_attribute *temp_attr;
1366 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1367 (ARRAY_SIZE(modinfo_attrs) + 1)),
1369 if (!mod->modinfo_attrs)
1372 temp_attr = mod->modinfo_attrs;
1373 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1375 (attr->test && attr->test(mod))) {
1376 memcpy(temp_attr, attr, sizeof(*temp_attr));
1377 sysfs_attr_init(&temp_attr->attr);
1378 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1385 static void module_remove_modinfo_attrs(struct module *mod)
1387 struct module_attribute *attr;
1390 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1391 /* pick a field to test for end of list */
1392 if (!attr->attr.name)
1394 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1398 kfree(mod->modinfo_attrs);
1401 static int mod_sysfs_init(struct module *mod)
1404 struct kobject *kobj;
1406 if (!module_sysfs_initialized) {
1407 printk(KERN_ERR "%s: module sysfs not initialized\n",
1413 kobj = kset_find_obj(module_kset, mod->name);
1415 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1421 mod->mkobj.mod = mod;
1423 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1424 mod->mkobj.kobj.kset = module_kset;
1425 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1428 kobject_put(&mod->mkobj.kobj);
1430 /* delay uevent until full sysfs population */
1435 static int mod_sysfs_setup(struct module *mod,
1436 struct kernel_param *kparam,
1437 unsigned int num_params)
1441 err = mod_sysfs_init(mod);
1445 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1446 if (!mod->holders_dir) {
1451 err = module_param_sysfs_setup(mod, kparam, num_params);
1453 goto out_unreg_holders;
1455 err = module_add_modinfo_attrs(mod);
1457 goto out_unreg_param;
1459 add_usage_links(mod);
1461 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1465 module_param_sysfs_remove(mod);
1467 kobject_put(mod->holders_dir);
1469 kobject_put(&mod->mkobj.kobj);
1474 static void mod_sysfs_fini(struct module *mod)
1476 kobject_put(&mod->mkobj.kobj);
1479 #else /* CONFIG_SYSFS */
1481 static inline int mod_sysfs_init(struct module *mod)
1486 static inline int mod_sysfs_setup(struct module *mod,
1487 struct kernel_param *kparam,
1488 unsigned int num_params)
1493 static inline int module_add_modinfo_attrs(struct module *mod)
1498 static inline void module_remove_modinfo_attrs(struct module *mod)
1502 static void mod_sysfs_fini(struct module *mod)
1506 static void del_usage_links(struct module *mod)
1510 #endif /* CONFIG_SYSFS */
1512 static void mod_kobject_remove(struct module *mod)
1514 del_usage_links(mod);
1515 module_remove_modinfo_attrs(mod);
1516 module_param_sysfs_remove(mod);
1517 kobject_put(mod->mkobj.drivers_dir);
1518 kobject_put(mod->holders_dir);
1519 mod_sysfs_fini(mod);
1523 * unlink the module with the whole machine is stopped with interrupts off
1524 * - this defends against kallsyms not taking locks
1526 static int __unlink_module(void *_mod)
1528 struct module *mod = _mod;
1529 list_del(&mod->list);
1533 /* Free a module, remove from lists, etc. */
1534 static void free_module(struct module *mod)
1536 trace_module_free(mod);
1538 /* Delete from various lists */
1539 mutex_lock(&module_mutex);
1540 stop_machine(__unlink_module, mod, NULL);
1541 mutex_unlock(&module_mutex);
1542 remove_notes_attrs(mod);
1543 remove_sect_attrs(mod);
1544 mod_kobject_remove(mod);
1546 /* Remove dynamic debug info */
1547 ddebug_remove_module(mod->name);
1549 /* Arch-specific cleanup. */
1550 module_arch_cleanup(mod);
1552 /* Module unload stuff */
1553 module_unload_free(mod);
1555 /* Free any allocated parameters. */
1556 destroy_params(mod->kp, mod->num_kp);
1558 /* This may be NULL, but that's OK */
1559 module_free(mod, mod->module_init);
1561 percpu_modfree(mod);
1562 #if defined(CONFIG_MODULE_UNLOAD)
1564 free_percpu(mod->refptr);
1566 /* Free lock-classes: */
1567 lockdep_free_key_range(mod->module_core, mod->core_size);
1569 /* Finally, free the core (containing the module structure) */
1570 module_free(mod, mod->module_core);
1573 update_protections(current->mm);
1577 void *__symbol_get(const char *symbol)
1579 struct module *owner;
1580 const struct kernel_symbol *sym;
1583 sym = find_symbol(symbol, &owner, NULL, true, true);
1584 if (sym && strong_try_module_get(owner))
1588 return sym ? (void *)sym->value : NULL;
1590 EXPORT_SYMBOL_GPL(__symbol_get);
1593 * Ensure that an exported symbol [global namespace] does not already exist
1594 * in the kernel or in some other module's exported symbol table.
1596 * You must hold the module_mutex.
1598 static int verify_export_symbols(struct module *mod)
1601 struct module *owner;
1602 const struct kernel_symbol *s;
1604 const struct kernel_symbol *sym;
1607 { mod->syms, mod->num_syms },
1608 { mod->gpl_syms, mod->num_gpl_syms },
1609 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1610 #ifdef CONFIG_UNUSED_SYMBOLS
1611 { mod->unused_syms, mod->num_unused_syms },
1612 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1616 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1617 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1618 if (find_symbol(s->name, &owner, NULL, true, false)) {
1620 "%s: exports duplicate symbol %s"
1622 mod->name, s->name, module_name(owner));
1630 /* Change all symbols so that st_value encodes the pointer directly. */
1631 static int simplify_symbols(Elf_Shdr *sechdrs,
1632 unsigned int symindex,
1634 unsigned int versindex,
1635 unsigned int pcpuindex,
1638 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1639 unsigned long secbase;
1640 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1642 const struct kernel_symbol *ksym;
1644 for (i = 1; i < n; i++) {
1645 switch (sym[i].st_shndx) {
1647 /* We compiled with -fno-common. These are not
1648 supposed to happen. */
1649 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1650 printk("%s: please compile with -fno-common\n",
1656 /* Don't need to do anything */
1657 DEBUGP("Absolute symbol: 0x%08lx\n",
1658 (long)sym[i].st_value);
1662 ksym = resolve_symbol_wait(sechdrs, versindex,
1663 strtab + sym[i].st_name,
1665 /* Ok if resolved. */
1666 if (ksym && !IS_ERR(ksym)) {
1667 sym[i].st_value = ksym->value;
1672 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1675 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
1676 mod->name, strtab + sym[i].st_name,
1678 ret = PTR_ERR(ksym) ?: -ENOENT;
1682 /* Divert to percpu allocation if a percpu var. */
1683 if (sym[i].st_shndx == pcpuindex)
1684 secbase = (unsigned long)mod_percpu(mod);
1686 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1687 sym[i].st_value += secbase;
1695 /* Additional bytes needed by arch in front of individual sections */
1696 unsigned int __weak arch_mod_section_prepend(struct module *mod,
1697 unsigned int section)
1699 /* default implementation just returns zero */
1703 /* Update size with this section: return offset. */
1704 static long get_offset(struct module *mod, unsigned int *size,
1705 Elf_Shdr *sechdr, unsigned int section)
1709 *size += arch_mod_section_prepend(mod, section);
1710 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1711 *size = ret + sechdr->sh_size;
1715 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1716 might -- code, read-only data, read-write data, small data. Tally
1717 sizes, and place the offsets into sh_entsize fields: high bit means it
1719 static void layout_sections(struct module *mod,
1720 const Elf_Ehdr *hdr,
1722 const char *secstrings)
1724 static unsigned long const masks[][2] = {
1725 /* NOTE: all executable code must be the first section
1726 * in this array; otherwise modify the text_size
1727 * finder in the two loops below */
1728 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1729 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1730 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1731 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1735 for (i = 0; i < hdr->e_shnum; i++)
1736 sechdrs[i].sh_entsize = ~0UL;
1738 DEBUGP("Core section allocation order:\n");
1739 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1740 for (i = 0; i < hdr->e_shnum; ++i) {
1741 Elf_Shdr *s = &sechdrs[i];
1743 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1744 || (s->sh_flags & masks[m][1])
1745 || s->sh_entsize != ~0UL
1746 || strstarts(secstrings + s->sh_name, ".init"))
1748 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1749 DEBUGP("\t%s\n", secstrings + s->sh_name);
1752 mod->core_text_size = mod->core_size;
1755 DEBUGP("Init section allocation order:\n");
1756 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1757 for (i = 0; i < hdr->e_shnum; ++i) {
1758 Elf_Shdr *s = &sechdrs[i];
1760 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1761 || (s->sh_flags & masks[m][1])
1762 || s->sh_entsize != ~0UL
1763 || !strstarts(secstrings + s->sh_name, ".init"))
1765 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1766 | INIT_OFFSET_MASK);
1767 DEBUGP("\t%s\n", secstrings + s->sh_name);
1770 mod->init_text_size = mod->init_size;
1774 static void set_license(struct module *mod, const char *license)
1777 license = "unspecified";
1779 if (!license_is_gpl_compatible(license)) {
1780 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1781 printk(KERN_WARNING "%s: module license '%s' taints "
1782 "kernel.\n", mod->name, license);
1783 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1787 /* Parse tag=value strings from .modinfo section */
1788 static char *next_string(char *string, unsigned long *secsize)
1790 /* Skip non-zero chars */
1793 if ((*secsize)-- <= 1)
1797 /* Skip any zero padding. */
1798 while (!string[0]) {
1800 if ((*secsize)-- <= 1)
1806 static char *get_modinfo(const Elf_Shdr *sechdrs,
1811 unsigned int taglen = strlen(tag);
1812 unsigned long size = sechdrs[info].sh_size;
1814 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1815 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1816 return p + taglen + 1;
1821 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1822 unsigned int infoindex)
1824 struct module_attribute *attr;
1827 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1830 get_modinfo(sechdrs,
1836 static void free_modinfo(struct module *mod)
1838 struct module_attribute *attr;
1841 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1847 #ifdef CONFIG_KALLSYMS
1849 /* lookup symbol in given range of kernel_symbols */
1850 static const struct kernel_symbol *lookup_symbol(const char *name,
1851 const struct kernel_symbol *start,
1852 const struct kernel_symbol *stop)
1854 const struct kernel_symbol *ks = start;
1855 for (; ks < stop; ks++)
1856 if (strcmp(ks->name, name) == 0)
1861 static int is_exported(const char *name, unsigned long value,
1862 const struct module *mod)
1864 const struct kernel_symbol *ks;
1866 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1868 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1869 return ks != NULL && ks->value == value;
1873 static char elf_type(const Elf_Sym *sym,
1875 const char *secstrings,
1878 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1879 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1884 if (sym->st_shndx == SHN_UNDEF)
1886 if (sym->st_shndx == SHN_ABS)
1888 if (sym->st_shndx >= SHN_LORESERVE)
1890 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1892 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1893 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1894 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1896 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1901 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1902 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1907 if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug"))
1912 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1915 const Elf_Shdr *sec;
1917 if (src->st_shndx == SHN_UNDEF
1918 || src->st_shndx >= shnum
1922 sec = sechdrs + src->st_shndx;
1923 if (!(sec->sh_flags & SHF_ALLOC)
1924 #ifndef CONFIG_KALLSYMS_ALL
1925 || !(sec->sh_flags & SHF_EXECINSTR)
1927 || (sec->sh_entsize & INIT_OFFSET_MASK))
1933 static unsigned long layout_symtab(struct module *mod,
1935 unsigned int symindex,
1936 unsigned int strindex,
1937 const Elf_Ehdr *hdr,
1938 const char *secstrings,
1939 unsigned long *pstroffs,
1940 unsigned long *strmap)
1942 unsigned long symoffs;
1943 Elf_Shdr *symsect = sechdrs + symindex;
1944 Elf_Shdr *strsect = sechdrs + strindex;
1947 unsigned int i, nsrc, ndst;
1949 /* Put symbol section at end of init part of module. */
1950 symsect->sh_flags |= SHF_ALLOC;
1951 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1952 symindex) | INIT_OFFSET_MASK;
1953 DEBUGP("\t%s\n", secstrings + symsect->sh_name);
1955 src = (void *)hdr + symsect->sh_offset;
1956 nsrc = symsect->sh_size / sizeof(*src);
1957 strtab = (void *)hdr + strsect->sh_offset;
1958 for (ndst = i = 1; i < nsrc; ++i, ++src)
1959 if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
1960 unsigned int j = src->st_name;
1962 while(!__test_and_set_bit(j, strmap) && strtab[j])
1967 /* Append room for core symbols at end of core part. */
1968 symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
1969 mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
1971 /* Put string table section at end of init part of module. */
1972 strsect->sh_flags |= SHF_ALLOC;
1973 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
1974 strindex) | INIT_OFFSET_MASK;
1975 DEBUGP("\t%s\n", secstrings + strsect->sh_name);
1977 /* Append room for core symbols' strings at end of core part. */
1978 *pstroffs = mod->core_size;
1979 __set_bit(0, strmap);
1980 mod->core_size += bitmap_weight(strmap, strsect->sh_size);
1985 static void add_kallsyms(struct module *mod,
1988 unsigned int symindex,
1989 unsigned int strindex,
1990 unsigned long symoffs,
1991 unsigned long stroffs,
1992 const char *secstrings,
1993 unsigned long *strmap)
1995 unsigned int i, ndst;
2000 mod->symtab = (void *)sechdrs[symindex].sh_addr;
2001 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
2002 mod->strtab = (void *)sechdrs[strindex].sh_addr;
2004 /* Set types up while we still have access to sections. */
2005 for (i = 0; i < mod->num_symtab; i++)
2006 mod->symtab[i].st_info
2007 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
2009 mod->core_symtab = dst = mod->module_core + symoffs;
2012 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
2013 if (!is_core_symbol(src, sechdrs, shnum))
2016 dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
2019 mod->core_num_syms = ndst;
2021 mod->core_strtab = s = mod->module_core + stroffs;
2022 for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i)
2023 if (test_bit(i, strmap))
2024 *++s = mod->strtab[i];
2027 static inline unsigned long layout_symtab(struct module *mod,
2029 unsigned int symindex,
2030 unsigned int strindex,
2031 const Elf_Ehdr *hdr,
2032 const char *secstrings,
2033 unsigned long *pstroffs,
2034 unsigned long *strmap)
2039 static inline void add_kallsyms(struct module *mod,
2042 unsigned int symindex,
2043 unsigned int strindex,
2044 unsigned long symoffs,
2045 unsigned long stroffs,
2046 const char *secstrings,
2047 const unsigned long *strmap)
2050 #endif /* CONFIG_KALLSYMS */
2052 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2054 #ifdef CONFIG_DYNAMIC_DEBUG
2055 if (ddebug_add_module(debug, num, debug->modname))
2056 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2061 static void dynamic_debug_remove(struct _ddebug *debug)
2064 ddebug_remove_module(debug->modname);
2067 static void *module_alloc_update_bounds(unsigned long size)
2069 void *ret = module_alloc(size);
2072 mutex_lock(&module_mutex);
2073 /* Update module bounds. */
2074 if ((unsigned long)ret < module_addr_min)
2075 module_addr_min = (unsigned long)ret;
2076 if ((unsigned long)ret + size > module_addr_max)
2077 module_addr_max = (unsigned long)ret + size;
2078 mutex_unlock(&module_mutex);
2083 #ifdef CONFIG_DEBUG_KMEMLEAK
2084 static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2085 const Elf_Shdr *sechdrs,
2086 const char *secstrings)
2090 /* only scan the sections containing data */
2091 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2093 for (i = 1; i < hdr->e_shnum; i++) {
2094 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2096 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
2097 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
2100 kmemleak_scan_area((void *)sechdrs[i].sh_addr,
2101 sechdrs[i].sh_size, GFP_KERNEL);
2105 static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2107 const char *secstrings)
2112 static int copy_and_check(Elf_Ehdr **hdrp,
2113 const void __user *umod, unsigned long len)
2118 if (len < sizeof(*hdr))
2121 /* Suck in entire file: we'll want most of it. */
2122 /* vmalloc barfs on "unusual" numbers. Check here */
2123 if (len > 64 * 1024 * 1024 || (hdr = *hdrp = vmalloc(len)) == NULL)
2126 if (copy_from_user(hdr, umod, len) != 0) {
2131 /* Sanity checks against insmoding binaries or wrong arch,
2132 weird elf version */
2133 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
2134 || hdr->e_type != ET_REL
2135 || !elf_check_arch(hdr)
2136 || hdr->e_shentsize != sizeof(Elf_Shdr)) {
2141 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
2152 static int check_modinfo(struct module *mod,
2153 const Elf_Shdr *sechdrs,
2154 unsigned int infoindex, unsigned int versindex)
2156 const char *modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2159 /* This is allowed: modprobe --force will invalidate it. */
2161 err = try_to_force_load(mod, "bad vermagic");
2164 } else if (!same_magic(modmagic, vermagic, versindex)) {
2165 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2166 mod->name, modmagic, vermagic);
2170 if (get_modinfo(sechdrs, infoindex, "staging")) {
2171 add_taint_module(mod, TAINT_CRAP);
2172 printk(KERN_WARNING "%s: module is from the staging directory,"
2173 " the quality is unknown, you have been warned.\n",
2179 static void find_module_sections(struct module *mod, Elf_Ehdr *hdr,
2180 Elf_Shdr *sechdrs, const char *secstrings)
2182 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2183 sizeof(*mod->kp), &mod->num_kp);
2184 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2185 sizeof(*mod->syms), &mod->num_syms);
2186 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2187 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2188 sizeof(*mod->gpl_syms),
2189 &mod->num_gpl_syms);
2190 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2191 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2192 "__ksymtab_gpl_future",
2193 sizeof(*mod->gpl_future_syms),
2194 &mod->num_gpl_future_syms);
2195 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2196 "__kcrctab_gpl_future");
2198 #ifdef CONFIG_UNUSED_SYMBOLS
2199 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2201 sizeof(*mod->unused_syms),
2202 &mod->num_unused_syms);
2203 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2204 "__kcrctab_unused");
2205 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2206 "__ksymtab_unused_gpl",
2207 sizeof(*mod->unused_gpl_syms),
2208 &mod->num_unused_gpl_syms);
2209 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2210 "__kcrctab_unused_gpl");
2212 #ifdef CONFIG_CONSTRUCTORS
2213 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2214 sizeof(*mod->ctors), &mod->num_ctors);
2217 #ifdef CONFIG_TRACEPOINTS
2218 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2220 sizeof(*mod->tracepoints),
2221 &mod->num_tracepoints);
2223 #ifdef CONFIG_EVENT_TRACING
2224 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2226 sizeof(*mod->trace_events),
2227 &mod->num_trace_events);
2229 * This section contains pointers to allocated objects in the trace
2230 * code and not scanning it leads to false positives.
2232 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2233 mod->num_trace_events, GFP_KERNEL);
2235 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2236 /* sechdrs[0].sh_size is always zero */
2237 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2239 sizeof(*mod->ftrace_callsites),
2240 &mod->num_ftrace_callsites);
2244 static struct module *move_module(struct module *mod,
2245 Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
2246 const char *secstrings, unsigned modindex)
2251 /* Do the allocs. */
2252 ptr = module_alloc_update_bounds(mod->core_size);
2254 * The pointer to this block is stored in the module structure
2255 * which is inside the block. Just mark it as not being a
2258 kmemleak_not_leak(ptr);
2260 return ERR_PTR(-ENOMEM);
2262 memset(ptr, 0, mod->core_size);
2263 mod->module_core = ptr;
2265 ptr = module_alloc_update_bounds(mod->init_size);
2267 * The pointer to this block is stored in the module structure
2268 * which is inside the block. This block doesn't need to be
2269 * scanned as it contains data and code that will be freed
2270 * after the module is initialized.
2272 kmemleak_ignore(ptr);
2273 if (!ptr && mod->init_size) {
2274 module_free(mod, mod->module_core);
2275 return ERR_PTR(-ENOMEM);
2277 memset(ptr, 0, mod->init_size);
2278 mod->module_init = ptr;
2280 /* Transfer each section which specifies SHF_ALLOC */
2281 DEBUGP("final section addresses:\n");
2282 for (i = 0; i < hdr->e_shnum; i++) {
2285 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2288 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2289 dest = mod->module_init
2290 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2292 dest = mod->module_core + sechdrs[i].sh_entsize;
2294 if (sechdrs[i].sh_type != SHT_NOBITS)
2295 memcpy(dest, (void *)sechdrs[i].sh_addr,
2296 sechdrs[i].sh_size);
2297 /* Update sh_addr to point to copy in image. */
2298 sechdrs[i].sh_addr = (unsigned long)dest;
2299 DEBUGP("\t0x%lx %s\n",
2300 sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2302 /* Module has been moved. */
2303 mod = (void *)sechdrs[modindex].sh_addr;
2304 kmemleak_load_module(mod, hdr, sechdrs, secstrings);
2308 /* Allocate and load the module: note that size of section 0 is always
2309 zero, and we rely on this for optional sections. */
2310 static noinline struct module *load_module(void __user *umod,
2312 const char __user *uargs)
2316 char *secstrings, *args, *strtab = NULL;
2318 unsigned int symindex = 0;
2319 unsigned int strindex = 0;
2320 unsigned int modindex, versindex, infoindex, pcpuindex;
2323 unsigned long symoffs, stroffs, *strmap;
2324 void __percpu *percpu;
2325 struct _ddebug *debug = NULL;
2326 unsigned int num_debug = 0;
2328 mm_segment_t old_fs;
2330 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2333 err = copy_and_check(&hdr, umod, len);
2335 return ERR_PTR(err);
2337 /* Convenience variables */
2338 sechdrs = (void *)hdr + hdr->e_shoff;
2339 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
2340 sechdrs[0].sh_addr = 0;
2342 for (i = 1; i < hdr->e_shnum; i++) {
2343 if (sechdrs[i].sh_type != SHT_NOBITS
2344 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
2347 /* Mark all sections sh_addr with their address in the
2349 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
2351 /* Internal symbols and strings. */
2352 if (sechdrs[i].sh_type == SHT_SYMTAB) {
2354 strindex = sechdrs[i].sh_link;
2355 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
2357 #ifndef CONFIG_MODULE_UNLOAD
2358 /* Don't load .exit sections */
2359 if (strstarts(secstrings+sechdrs[i].sh_name, ".exit"))
2360 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
2364 modindex = find_sec(hdr, sechdrs, secstrings,
2365 ".gnu.linkonce.this_module");
2367 printk(KERN_WARNING "No module found in object\n");
2371 /* This is temporary: point mod into copy of data. */
2372 mod = (void *)sechdrs[modindex].sh_addr;
2374 if (symindex == 0) {
2375 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2381 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
2382 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
2383 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
2385 /* Don't keep modinfo and version sections. */
2386 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2387 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2389 /* Check module struct version now, before we try to use module. */
2390 if (!check_modstruct_version(sechdrs, versindex, mod)) {
2395 err = check_modinfo(mod, sechdrs, infoindex, versindex);
2399 /* Now copy in args */
2400 args = strndup_user(uargs, ~0UL >> 1);
2402 err = PTR_ERR(args);
2406 strmap = kzalloc(BITS_TO_LONGS(sechdrs[strindex].sh_size)
2407 * sizeof(long), GFP_KERNEL);
2413 mod->state = MODULE_STATE_COMING;
2415 /* Allow arches to frob section contents and sizes. */
2416 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
2421 /* We have a special allocation for this section. */
2422 err = percpu_modalloc(mod, sechdrs[pcpuindex].sh_size,
2423 sechdrs[pcpuindex].sh_addralign);
2426 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2428 /* Keep this around for failure path. */
2429 percpu = mod_percpu(mod);
2431 /* Determine total sizes, and put offsets in sh_entsize. For now
2432 this is done generically; there doesn't appear to be any
2433 special cases for the architectures. */
2434 layout_sections(mod, hdr, sechdrs, secstrings);
2435 symoffs = layout_symtab(mod, sechdrs, symindex, strindex, hdr,
2436 secstrings, &stroffs, strmap);
2438 /* Allocate and move to the final place */
2439 mod = move_module(mod, hdr, sechdrs, secstrings, modindex);
2445 #if defined(CONFIG_MODULE_UNLOAD)
2446 mod->refptr = alloc_percpu(struct module_ref);
2452 /* Now we've moved module, initialize linked lists, etc. */
2453 module_unload_init(mod);
2455 /* Set up license info based on the info section */
2456 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2459 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2460 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2461 * using GPL-only symbols it needs.
2463 if (strcmp(mod->name, "ndiswrapper") == 0)
2464 add_taint(TAINT_PROPRIETARY_MODULE);
2466 /* driverloader was caught wrongly pretending to be under GPL */
2467 if (strcmp(mod->name, "driverloader") == 0)
2468 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2470 /* Set up MODINFO_ATTR fields */
2471 setup_modinfo(mod, sechdrs, infoindex);
2473 /* Fix up syms, so that st_value is a pointer to location. */
2474 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2479 /* Now we've got everything in the final locations, we can
2480 * find optional sections. */
2481 find_module_sections(mod, hdr, sechdrs, secstrings);
2483 #ifdef CONFIG_MODVERSIONS
2484 if ((mod->num_syms && !mod->crcs)
2485 || (mod->num_gpl_syms && !mod->gpl_crcs)
2486 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2487 #ifdef CONFIG_UNUSED_SYMBOLS
2488 || (mod->num_unused_syms && !mod->unused_crcs)
2489 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2492 err = try_to_force_load(mod,
2493 "no versions for exported symbols");
2499 /* Now do relocations. */
2500 for (i = 1; i < hdr->e_shnum; i++) {
2501 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2502 unsigned int info = sechdrs[i].sh_info;
2504 /* Not a valid relocation section? */
2505 if (info >= hdr->e_shnum)
2508 /* Don't bother with non-allocated sections */
2509 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2512 if (sechdrs[i].sh_type == SHT_REL)
2513 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2514 else if (sechdrs[i].sh_type == SHT_RELA)
2515 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2521 /* Set up and sort exception table */
2522 mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
2523 sizeof(*mod->extable), &mod->num_exentries);
2524 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2526 /* Finally, copy percpu area over. */
2527 percpu_modcopy(mod, (void *)sechdrs[pcpuindex].sh_addr,
2528 sechdrs[pcpuindex].sh_size);
2530 add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex,
2531 symoffs, stroffs, secstrings, strmap);
2536 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2537 sizeof(*debug), &num_debug);
2539 err = module_finalize(hdr, sechdrs, mod);
2543 /* flush the icache in correct context */
2548 * Flush the instruction cache, since we've played with text.
2549 * Do it before processing of module parameters, so the module
2550 * can provide parameter accessor functions of its own.
2552 if (mod->module_init)
2553 flush_icache_range((unsigned long)mod->module_init,
2554 (unsigned long)mod->module_init
2556 flush_icache_range((unsigned long)mod->module_core,
2557 (unsigned long)mod->module_core + mod->core_size);
2562 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2563 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2566 /* Now sew it into the lists so we can get lockdep and oops
2567 * info during argument parsing. Noone should access us, since
2568 * strong_try_module_get() will fail.
2569 * lockdep/oops can run asynchronous, so use the RCU list insertion
2570 * function to insert in a way safe to concurrent readers.
2571 * The mutex protects against concurrent writers.
2573 mutex_lock(&module_mutex);
2574 if (find_module(mod->name)) {
2580 dynamic_debug_setup(debug, num_debug);
2582 /* Find duplicate symbols */
2583 err = verify_export_symbols(mod);
2587 list_add_rcu(&mod->list, &modules);
2588 mutex_unlock(&module_mutex);
2590 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2594 err = mod_sysfs_setup(mod, mod->kp, mod->num_kp);
2598 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2599 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2601 /* Get rid of temporary copy */
2604 trace_module_load(mod);
2610 mutex_lock(&module_mutex);
2611 /* Unlink carefully: kallsyms could be walking list. */
2612 list_del_rcu(&mod->list);
2614 dynamic_debug_remove(debug);
2616 mutex_unlock(&module_mutex);
2617 synchronize_sched();
2618 module_arch_cleanup(mod);
2621 module_unload_free(mod);
2622 #if defined(CONFIG_MODULE_UNLOAD)
2623 free_percpu(mod->refptr);
2626 module_free(mod, mod->module_init);
2627 module_free(mod, mod->module_core);
2628 /* mod will be freed with core. Don't access it beyond this line! */
2630 free_percpu(percpu);
2636 return ERR_PTR(err);
2639 printk(KERN_ERR "Module len %lu truncated\n", len);
2644 /* Call module constructors. */
2645 static void do_mod_ctors(struct module *mod)
2647 #ifdef CONFIG_CONSTRUCTORS
2650 for (i = 0; i < mod->num_ctors; i++)
2655 /* This is where the real work happens */
2656 SYSCALL_DEFINE3(init_module, void __user *, umod,
2657 unsigned long, len, const char __user *, uargs)
2662 /* Must have permission */
2663 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2666 /* Do all the hard work */
2667 mod = load_module(umod, len, uargs);
2669 return PTR_ERR(mod);
2671 blocking_notifier_call_chain(&module_notify_list,
2672 MODULE_STATE_COMING, mod);
2675 /* Start the module */
2676 if (mod->init != NULL)
2677 ret = do_one_initcall(mod->init);
2679 /* Init routine failed: abort. Try to protect us from
2680 buggy refcounters. */
2681 mod->state = MODULE_STATE_GOING;
2682 synchronize_sched();
2684 blocking_notifier_call_chain(&module_notify_list,
2685 MODULE_STATE_GOING, mod);
2687 wake_up(&module_wq);
2692 "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2693 "%s: loading module anyway...\n",
2694 __func__, mod->name, ret,
2699 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2700 mod->state = MODULE_STATE_LIVE;
2701 wake_up(&module_wq);
2702 blocking_notifier_call_chain(&module_notify_list,
2703 MODULE_STATE_LIVE, mod);
2705 /* We need to finish all async code before the module init sequence is done */
2706 async_synchronize_full();
2708 mutex_lock(&module_mutex);
2709 /* Drop initial reference. */
2711 trim_init_extable(mod);
2712 #ifdef CONFIG_KALLSYMS
2713 mod->num_symtab = mod->core_num_syms;
2714 mod->symtab = mod->core_symtab;
2715 mod->strtab = mod->core_strtab;
2717 module_free(mod, mod->module_init);
2718 mod->module_init = NULL;
2720 mod->init_text_size = 0;
2721 mutex_unlock(&module_mutex);
2726 static inline int within(unsigned long addr, void *start, unsigned long size)
2728 return ((void *)addr >= start && (void *)addr < start + size);
2731 #ifdef CONFIG_KALLSYMS
2733 * This ignores the intensely annoying "mapping symbols" found
2734 * in ARM ELF files: $a, $t and $d.
2736 static inline int is_arm_mapping_symbol(const char *str)
2738 return str[0] == '$' && strchr("atd", str[1])
2739 && (str[2] == '\0' || str[2] == '.');
2742 static const char *get_ksymbol(struct module *mod,
2744 unsigned long *size,
2745 unsigned long *offset)
2747 unsigned int i, best = 0;
2748 unsigned long nextval;
2750 /* At worse, next value is at end of module */
2751 if (within_module_init(addr, mod))
2752 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2754 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2756 /* Scan for closest preceeding symbol, and next symbol. (ELF
2757 starts real symbols at 1). */
2758 for (i = 1; i < mod->num_symtab; i++) {
2759 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2762 /* We ignore unnamed symbols: they're uninformative
2763 * and inserted at a whim. */
2764 if (mod->symtab[i].st_value <= addr
2765 && mod->symtab[i].st_value > mod->symtab[best].st_value
2766 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2767 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2769 if (mod->symtab[i].st_value > addr
2770 && mod->symtab[i].st_value < nextval
2771 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2772 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2773 nextval = mod->symtab[i].st_value;
2780 *size = nextval - mod->symtab[best].st_value;
2782 *offset = addr - mod->symtab[best].st_value;
2783 return mod->strtab + mod->symtab[best].st_name;
2786 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2787 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2788 const char *module_address_lookup(unsigned long addr,
2789 unsigned long *size,
2790 unsigned long *offset,
2795 const char *ret = NULL;
2798 list_for_each_entry_rcu(mod, &modules, list) {
2799 if (within_module_init(addr, mod) ||
2800 within_module_core(addr, mod)) {
2802 *modname = mod->name;
2803 ret = get_ksymbol(mod, addr, size, offset);
2807 /* Make a copy in here where it's safe */
2809 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2816 int lookup_module_symbol_name(unsigned long addr, char *symname)
2821 list_for_each_entry_rcu(mod, &modules, list) {
2822 if (within_module_init(addr, mod) ||
2823 within_module_core(addr, mod)) {
2826 sym = get_ksymbol(mod, addr, NULL, NULL);
2829 strlcpy(symname, sym, KSYM_NAME_LEN);
2839 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2840 unsigned long *offset, char *modname, char *name)
2845 list_for_each_entry_rcu(mod, &modules, list) {
2846 if (within_module_init(addr, mod) ||
2847 within_module_core(addr, mod)) {
2850 sym = get_ksymbol(mod, addr, size, offset);
2854 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2856 strlcpy(name, sym, KSYM_NAME_LEN);
2866 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2867 char *name, char *module_name, int *exported)
2872 list_for_each_entry_rcu(mod, &modules, list) {
2873 if (symnum < mod->num_symtab) {
2874 *value = mod->symtab[symnum].st_value;
2875 *type = mod->symtab[symnum].st_info;
2876 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2878 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2879 *exported = is_exported(name, *value, mod);
2883 symnum -= mod->num_symtab;
2889 static unsigned long mod_find_symname(struct module *mod, const char *name)
2893 for (i = 0; i < mod->num_symtab; i++)
2894 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2895 mod->symtab[i].st_info != 'U')
2896 return mod->symtab[i].st_value;
2900 /* Look for this name: can be of form module:name. */
2901 unsigned long module_kallsyms_lookup_name(const char *name)
2905 unsigned long ret = 0;
2907 /* Don't lock: we're in enough trouble already. */
2909 if ((colon = strchr(name, ':')) != NULL) {
2911 if ((mod = find_module(name)) != NULL)
2912 ret = mod_find_symname(mod, colon+1);
2915 list_for_each_entry_rcu(mod, &modules, list)
2916 if ((ret = mod_find_symname(mod, name)) != 0)
2923 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
2924 struct module *, unsigned long),
2931 list_for_each_entry(mod, &modules, list) {
2932 for (i = 0; i < mod->num_symtab; i++) {
2933 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
2934 mod, mod->symtab[i].st_value);
2941 #endif /* CONFIG_KALLSYMS */
2943 static char *module_flags(struct module *mod, char *buf)
2948 mod->state == MODULE_STATE_GOING ||
2949 mod->state == MODULE_STATE_COMING) {
2951 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2953 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2955 if (mod->taints & (1 << TAINT_CRAP))
2958 * TAINT_FORCED_RMMOD: could be added.
2959 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2963 /* Show a - for module-is-being-unloaded */
2964 if (mod->state == MODULE_STATE_GOING)
2966 /* Show a + for module-is-being-loaded */
2967 if (mod->state == MODULE_STATE_COMING)
2976 #ifdef CONFIG_PROC_FS
2977 /* Called by the /proc file system to return a list of modules. */
2978 static void *m_start(struct seq_file *m, loff_t *pos)
2980 mutex_lock(&module_mutex);
2981 return seq_list_start(&modules, *pos);
2984 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2986 return seq_list_next(p, &modules, pos);
2989 static void m_stop(struct seq_file *m, void *p)
2991 mutex_unlock(&module_mutex);
2994 static int m_show(struct seq_file *m, void *p)
2996 struct module *mod = list_entry(p, struct module, list);
2999 seq_printf(m, "%s %u",
3000 mod->name, mod->init_size + mod->core_size);
3001 print_unload_info(m, mod);
3003 /* Informative for users. */
3004 seq_printf(m, " %s",
3005 mod->state == MODULE_STATE_GOING ? "Unloading":
3006 mod->state == MODULE_STATE_COMING ? "Loading":
3008 /* Used by oprofile and other similar tools. */
3009 seq_printf(m, " 0x%p", mod->module_core);
3013 seq_printf(m, " %s", module_flags(mod, buf));
3015 seq_printf(m, "\n");
3019 /* Format: modulename size refcount deps address
3021 Where refcount is a number or -, and deps is a comma-separated list
3024 static const struct seq_operations modules_op = {
3031 static int modules_open(struct inode *inode, struct file *file)
3033 return seq_open(file, &modules_op);
3036 static const struct file_operations proc_modules_operations = {
3037 .open = modules_open,
3039 .llseek = seq_lseek,
3040 .release = seq_release,
3043 static int __init proc_modules_init(void)
3045 proc_create("modules", 0, NULL, &proc_modules_operations);
3048 module_init(proc_modules_init);
3051 /* Given an address, look for it in the module exception tables. */
3052 const struct exception_table_entry *search_module_extables(unsigned long addr)
3054 const struct exception_table_entry *e = NULL;
3058 list_for_each_entry_rcu(mod, &modules, list) {
3059 if (mod->num_exentries == 0)
3062 e = search_extable(mod->extable,
3063 mod->extable + mod->num_exentries - 1,
3070 /* Now, if we found one, we are running inside it now, hence
3071 we cannot unload the module, hence no refcnt needed. */
3076 * is_module_address - is this address inside a module?
3077 * @addr: the address to check.
3079 * See is_module_text_address() if you simply want to see if the address
3080 * is code (not data).
3082 bool is_module_address(unsigned long addr)
3087 ret = __module_address(addr) != NULL;
3094 * __module_address - get the module which contains an address.
3095 * @addr: the address.
3097 * Must be called with preempt disabled or module mutex held so that
3098 * module doesn't get freed during this.
3100 struct module *__module_address(unsigned long addr)
3104 if (addr < module_addr_min || addr > module_addr_max)
3107 list_for_each_entry_rcu(mod, &modules, list)
3108 if (within_module_core(addr, mod)
3109 || within_module_init(addr, mod))
3113 EXPORT_SYMBOL_GPL(__module_address);
3116 * is_module_text_address - is this address inside module code?
3117 * @addr: the address to check.
3119 * See is_module_address() if you simply want to see if the address is
3120 * anywhere in a module. See kernel_text_address() for testing if an
3121 * address corresponds to kernel or module code.
3123 bool is_module_text_address(unsigned long addr)
3128 ret = __module_text_address(addr) != NULL;
3135 * __module_text_address - get the module whose code contains an address.
3136 * @addr: the address.
3138 * Must be called with preempt disabled or module mutex held so that
3139 * module doesn't get freed during this.
3141 struct module *__module_text_address(unsigned long addr)
3143 struct module *mod = __module_address(addr);
3145 /* Make sure it's within the text section. */
3146 if (!within(addr, mod->module_init, mod->init_text_size)
3147 && !within(addr, mod->module_core, mod->core_text_size))
3152 EXPORT_SYMBOL_GPL(__module_text_address);
3154 /* Don't grab lock, we're oopsing. */
3155 void print_modules(void)
3160 printk(KERN_DEFAULT "Modules linked in:");
3161 /* Most callers should already have preempt disabled, but make sure */
3163 list_for_each_entry_rcu(mod, &modules, list)
3164 printk(" %s%s", mod->name, module_flags(mod, buf));
3166 if (last_unloaded_module[0])
3167 printk(" [last unloaded: %s]", last_unloaded_module);
3171 #ifdef CONFIG_MODVERSIONS
3172 /* Generate the signature for all relevant module structures here.
3173 * If these change, we don't want to try to parse the module. */
3174 void module_layout(struct module *mod,
3175 struct modversion_info *ver,
3176 struct kernel_param *kp,
3177 struct kernel_symbol *ks,
3178 struct tracepoint *tp)
3181 EXPORT_SYMBOL(module_layout);
3184 #ifdef CONFIG_TRACEPOINTS
3185 void module_update_tracepoints(void)
3189 mutex_lock(&module_mutex);
3190 list_for_each_entry(mod, &modules, list)
3192 tracepoint_update_probe_range(mod->tracepoints,
3193 mod->tracepoints + mod->num_tracepoints);
3194 mutex_unlock(&module_mutex);
3198 * Returns 0 if current not found.
3199 * Returns 1 if current found.
3201 int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3203 struct module *iter_mod;
3206 mutex_lock(&module_mutex);
3207 list_for_each_entry(iter_mod, &modules, list) {
3208 if (!iter_mod->taints) {
3210 * Sorted module list
3212 if (iter_mod < iter->module)
3214 else if (iter_mod > iter->module)
3215 iter->tracepoint = NULL;
3216 found = tracepoint_get_iter_range(&iter->tracepoint,
3217 iter_mod->tracepoints,
3218 iter_mod->tracepoints
3219 + iter_mod->num_tracepoints);
3221 iter->module = iter_mod;
3226 mutex_unlock(&module_mutex);