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);
117 char *secstrings, *args, *strtab;
118 unsigned long *strmap;
119 unsigned long symoffs, stroffs;
121 unsigned int sym, str, mod, vers, info, pcpu;
125 /* We require a truly strong try_module_get(): 0 means failure due to
126 ongoing or failed initialization etc. */
127 static inline int strong_try_module_get(struct module *mod)
129 if (mod && mod->state == MODULE_STATE_COMING)
131 if (try_module_get(mod))
137 static inline void add_taint_module(struct module *mod, unsigned flag)
140 mod->taints |= (1U << flag);
144 * A thread that wants to hold a reference to a module only while it
145 * is running can call this to safely exit. nfsd and lockd use this.
147 void __module_put_and_exit(struct module *mod, long code)
152 EXPORT_SYMBOL(__module_put_and_exit);
154 /* Find a module section: 0 means not found. */
155 static unsigned int find_sec(Elf_Ehdr *hdr,
157 const char *secstrings,
162 for (i = 1; i < hdr->e_shnum; i++)
163 /* Alloc bit cleared means "ignore it." */
164 if ((sechdrs[i].sh_flags & SHF_ALLOC)
165 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
170 /* Find a module section, or NULL. */
171 static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
172 const char *secstrings, const char *name)
174 /* Section 0 has sh_addr 0. */
175 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
178 /* Find a module section, or NULL. Fill in number of "objects" in section. */
179 static void *section_objs(Elf_Ehdr *hdr,
181 const char *secstrings,
186 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
188 /* Section 0 has sh_addr 0 and sh_size 0. */
189 *num = sechdrs[sec].sh_size / object_size;
190 return (void *)sechdrs[sec].sh_addr;
193 /* Provided by the linker */
194 extern const struct kernel_symbol __start___ksymtab[];
195 extern const struct kernel_symbol __stop___ksymtab[];
196 extern const struct kernel_symbol __start___ksymtab_gpl[];
197 extern const struct kernel_symbol __stop___ksymtab_gpl[];
198 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
199 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
200 extern const unsigned long __start___kcrctab[];
201 extern const unsigned long __start___kcrctab_gpl[];
202 extern const unsigned long __start___kcrctab_gpl_future[];
203 #ifdef CONFIG_UNUSED_SYMBOLS
204 extern const struct kernel_symbol __start___ksymtab_unused[];
205 extern const struct kernel_symbol __stop___ksymtab_unused[];
206 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
207 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
208 extern const unsigned long __start___kcrctab_unused[];
209 extern const unsigned long __start___kcrctab_unused_gpl[];
212 #ifndef CONFIG_MODVERSIONS
213 #define symversion(base, idx) NULL
215 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
218 static bool each_symbol_in_section(const struct symsearch *arr,
219 unsigned int arrsize,
220 struct module *owner,
221 bool (*fn)(const struct symsearch *syms,
222 struct module *owner,
223 unsigned int symnum, void *data),
228 for (j = 0; j < arrsize; j++) {
229 for (i = 0; i < arr[j].stop - arr[j].start; i++)
230 if (fn(&arr[j], owner, i, data))
237 /* Returns true as soon as fn returns true, otherwise false. */
238 bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
239 unsigned int symnum, void *data), void *data)
242 static const struct symsearch arr[] = {
243 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
244 NOT_GPL_ONLY, false },
245 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
246 __start___kcrctab_gpl,
248 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
249 __start___kcrctab_gpl_future,
250 WILL_BE_GPL_ONLY, false },
251 #ifdef CONFIG_UNUSED_SYMBOLS
252 { __start___ksymtab_unused, __stop___ksymtab_unused,
253 __start___kcrctab_unused,
254 NOT_GPL_ONLY, true },
255 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
256 __start___kcrctab_unused_gpl,
261 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
264 list_for_each_entry_rcu(mod, &modules, list) {
265 struct symsearch arr[] = {
266 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
267 NOT_GPL_ONLY, false },
268 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
271 { mod->gpl_future_syms,
272 mod->gpl_future_syms + mod->num_gpl_future_syms,
273 mod->gpl_future_crcs,
274 WILL_BE_GPL_ONLY, false },
275 #ifdef CONFIG_UNUSED_SYMBOLS
277 mod->unused_syms + mod->num_unused_syms,
279 NOT_GPL_ONLY, true },
280 { mod->unused_gpl_syms,
281 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
282 mod->unused_gpl_crcs,
287 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
292 EXPORT_SYMBOL_GPL(each_symbol);
294 struct find_symbol_arg {
301 struct module *owner;
302 const unsigned long *crc;
303 const struct kernel_symbol *sym;
306 static bool find_symbol_in_section(const struct symsearch *syms,
307 struct module *owner,
308 unsigned int symnum, void *data)
310 struct find_symbol_arg *fsa = data;
312 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
316 if (syms->licence == GPL_ONLY)
318 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
319 printk(KERN_WARNING "Symbol %s is being used "
320 "by a non-GPL module, which will not "
321 "be allowed in the future\n", fsa->name);
322 printk(KERN_WARNING "Please see the file "
323 "Documentation/feature-removal-schedule.txt "
324 "in the kernel source tree for more details.\n");
328 #ifdef CONFIG_UNUSED_SYMBOLS
329 if (syms->unused && fsa->warn) {
330 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
331 "however this module is using it.\n", fsa->name);
333 "This symbol will go away in the future.\n");
335 "Please evalute if this is the right api to use and if "
336 "it really is, submit a report the linux kernel "
337 "mailinglist together with submitting your code for "
343 fsa->crc = symversion(syms->crcs, symnum);
344 fsa->sym = &syms->start[symnum];
348 /* Find a symbol and return it, along with, (optional) crc and
349 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
350 const struct kernel_symbol *find_symbol(const char *name,
351 struct module **owner,
352 const unsigned long **crc,
356 struct find_symbol_arg fsa;
362 if (each_symbol(find_symbol_in_section, &fsa)) {
370 DEBUGP("Failed to find symbol %s\n", name);
373 EXPORT_SYMBOL_GPL(find_symbol);
375 /* Search for module by name: must hold module_mutex. */
376 struct module *find_module(const char *name)
380 list_for_each_entry(mod, &modules, list) {
381 if (strcmp(mod->name, name) == 0)
386 EXPORT_SYMBOL_GPL(find_module);
390 static inline void __percpu *mod_percpu(struct module *mod)
395 static int percpu_modalloc(struct module *mod,
396 unsigned long size, unsigned long align)
398 if (align > PAGE_SIZE) {
399 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
400 mod->name, align, PAGE_SIZE);
404 mod->percpu = __alloc_reserved_percpu(size, align);
407 "%s: Could not allocate %lu bytes percpu data\n",
411 mod->percpu_size = size;
415 static void percpu_modfree(struct module *mod)
417 free_percpu(mod->percpu);
420 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
422 const char *secstrings)
424 return find_sec(hdr, sechdrs, secstrings, ".data..percpu");
427 static void percpu_modcopy(struct module *mod,
428 const void *from, unsigned long size)
432 for_each_possible_cpu(cpu)
433 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
437 * is_module_percpu_address - test whether address is from module static percpu
438 * @addr: address to test
440 * Test whether @addr belongs to module static percpu area.
443 * %true if @addr is from module static percpu area
445 bool is_module_percpu_address(unsigned long addr)
452 list_for_each_entry_rcu(mod, &modules, list) {
453 if (!mod->percpu_size)
455 for_each_possible_cpu(cpu) {
456 void *start = per_cpu_ptr(mod->percpu, cpu);
458 if ((void *)addr >= start &&
459 (void *)addr < start + mod->percpu_size) {
470 #else /* ... !CONFIG_SMP */
472 static inline void __percpu *mod_percpu(struct module *mod)
476 static inline int percpu_modalloc(struct module *mod,
477 unsigned long size, unsigned long align)
481 static inline void percpu_modfree(struct module *mod)
484 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
486 const char *secstrings)
490 static inline void percpu_modcopy(struct module *mod,
491 const void *from, unsigned long size)
493 /* pcpusec should be 0, and size of that section should be 0. */
496 bool is_module_percpu_address(unsigned long addr)
501 #endif /* CONFIG_SMP */
503 #define MODINFO_ATTR(field) \
504 static void setup_modinfo_##field(struct module *mod, const char *s) \
506 mod->field = kstrdup(s, GFP_KERNEL); \
508 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
509 struct module *mod, char *buffer) \
511 return sprintf(buffer, "%s\n", mod->field); \
513 static int modinfo_##field##_exists(struct module *mod) \
515 return mod->field != NULL; \
517 static void free_modinfo_##field(struct module *mod) \
522 static struct module_attribute modinfo_##field = { \
523 .attr = { .name = __stringify(field), .mode = 0444 }, \
524 .show = show_modinfo_##field, \
525 .setup = setup_modinfo_##field, \
526 .test = modinfo_##field##_exists, \
527 .free = free_modinfo_##field, \
530 MODINFO_ATTR(version);
531 MODINFO_ATTR(srcversion);
533 static char last_unloaded_module[MODULE_NAME_LEN+1];
535 #ifdef CONFIG_MODULE_UNLOAD
537 EXPORT_TRACEPOINT_SYMBOL(module_get);
539 /* Init the unload section of the module. */
540 static int module_unload_init(struct module *mod)
542 mod->refptr = alloc_percpu(struct module_ref);
546 INIT_LIST_HEAD(&mod->source_list);
547 INIT_LIST_HEAD(&mod->target_list);
549 /* Hold reference count during initialization. */
550 __this_cpu_write(mod->refptr->incs, 1);
551 /* Backwards compatibility macros put refcount during init. */
552 mod->waiter = current;
557 /* Does a already use b? */
558 static int already_uses(struct module *a, struct module *b)
560 struct module_use *use;
562 list_for_each_entry(use, &b->source_list, source_list) {
563 if (use->source == a) {
564 DEBUGP("%s uses %s!\n", a->name, b->name);
568 DEBUGP("%s does not use %s!\n", a->name, b->name);
574 * - we add 'a' as a "source", 'b' as a "target" of module use
575 * - the module_use is added to the list of 'b' sources (so
576 * 'b' can walk the list to see who sourced them), and of 'a'
577 * targets (so 'a' can see what modules it targets).
579 static int add_module_usage(struct module *a, struct module *b)
581 struct module_use *use;
583 DEBUGP("Allocating new usage for %s.\n", a->name);
584 use = kmalloc(sizeof(*use), GFP_ATOMIC);
586 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
592 list_add(&use->source_list, &b->source_list);
593 list_add(&use->target_list, &a->target_list);
597 /* Module a uses b: caller needs module_mutex() */
598 int ref_module(struct module *a, struct module *b)
602 if (b == NULL || already_uses(a, b))
605 /* If module isn't available, we fail. */
606 err = strong_try_module_get(b);
610 err = add_module_usage(a, b);
617 EXPORT_SYMBOL_GPL(ref_module);
619 /* Clear the unload stuff of the module. */
620 static void module_unload_free(struct module *mod)
622 struct module_use *use, *tmp;
624 mutex_lock(&module_mutex);
625 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
626 struct module *i = use->target;
627 DEBUGP("%s unusing %s\n", mod->name, i->name);
629 list_del(&use->source_list);
630 list_del(&use->target_list);
633 mutex_unlock(&module_mutex);
635 free_percpu(mod->refptr);
638 #ifdef CONFIG_MODULE_FORCE_UNLOAD
639 static inline int try_force_unload(unsigned int flags)
641 int ret = (flags & O_TRUNC);
643 add_taint(TAINT_FORCED_RMMOD);
647 static inline int try_force_unload(unsigned int flags)
651 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
660 /* Whole machine is stopped with interrupts off when this runs. */
661 static int __try_stop_module(void *_sref)
663 struct stopref *sref = _sref;
665 /* If it's not unused, quit unless we're forcing. */
666 if (module_refcount(sref->mod) != 0) {
667 if (!(*sref->forced = try_force_unload(sref->flags)))
671 /* Mark it as dying. */
672 sref->mod->state = MODULE_STATE_GOING;
676 static int try_stop_module(struct module *mod, int flags, int *forced)
678 if (flags & O_NONBLOCK) {
679 struct stopref sref = { mod, flags, forced };
681 return stop_machine(__try_stop_module, &sref, NULL);
683 /* We don't need to stop the machine for this. */
684 mod->state = MODULE_STATE_GOING;
690 unsigned int module_refcount(struct module *mod)
692 unsigned int incs = 0, decs = 0;
695 for_each_possible_cpu(cpu)
696 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
698 * ensure the incs are added up after the decs.
699 * module_put ensures incs are visible before decs with smp_wmb.
701 * This 2-count scheme avoids the situation where the refcount
702 * for CPU0 is read, then CPU0 increments the module refcount,
703 * then CPU1 drops that refcount, then the refcount for CPU1 is
704 * read. We would record a decrement but not its corresponding
705 * increment so we would see a low count (disaster).
707 * Rare situation? But module_refcount can be preempted, and we
708 * might be tallying up 4096+ CPUs. So it is not impossible.
711 for_each_possible_cpu(cpu)
712 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
715 EXPORT_SYMBOL(module_refcount);
717 /* This exists whether we can unload or not */
718 static void free_module(struct module *mod);
720 static void wait_for_zero_refcount(struct module *mod)
722 /* Since we might sleep for some time, release the mutex first */
723 mutex_unlock(&module_mutex);
725 DEBUGP("Looking at refcount...\n");
726 set_current_state(TASK_UNINTERRUPTIBLE);
727 if (module_refcount(mod) == 0)
731 current->state = TASK_RUNNING;
732 mutex_lock(&module_mutex);
735 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
739 char name[MODULE_NAME_LEN];
742 if (!capable(CAP_SYS_MODULE) || modules_disabled)
745 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
747 name[MODULE_NAME_LEN-1] = '\0';
749 if (mutex_lock_interruptible(&module_mutex) != 0)
752 mod = find_module(name);
758 if (!list_empty(&mod->source_list)) {
759 /* Other modules depend on us: get rid of them first. */
764 /* Doing init or already dying? */
765 if (mod->state != MODULE_STATE_LIVE) {
766 /* FIXME: if (force), slam module count and wake up
768 DEBUGP("%s already dying\n", mod->name);
773 /* If it has an init func, it must have an exit func to unload */
774 if (mod->init && !mod->exit) {
775 forced = try_force_unload(flags);
777 /* This module can't be removed */
783 /* Set this up before setting mod->state */
784 mod->waiter = current;
786 /* Stop the machine so refcounts can't move and disable module. */
787 ret = try_stop_module(mod, flags, &forced);
791 /* Never wait if forced. */
792 if (!forced && module_refcount(mod) != 0)
793 wait_for_zero_refcount(mod);
795 mutex_unlock(&module_mutex);
796 /* Final destruction now noone is using it. */
797 if (mod->exit != NULL)
799 blocking_notifier_call_chain(&module_notify_list,
800 MODULE_STATE_GOING, mod);
801 async_synchronize_full();
803 /* Store the name of the last unloaded module for diagnostic purposes */
804 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
809 mutex_unlock(&module_mutex);
813 static inline void print_unload_info(struct seq_file *m, struct module *mod)
815 struct module_use *use;
816 int printed_something = 0;
818 seq_printf(m, " %u ", module_refcount(mod));
820 /* Always include a trailing , so userspace can differentiate
821 between this and the old multi-field proc format. */
822 list_for_each_entry(use, &mod->source_list, source_list) {
823 printed_something = 1;
824 seq_printf(m, "%s,", use->source->name);
827 if (mod->init != NULL && mod->exit == NULL) {
828 printed_something = 1;
829 seq_printf(m, "[permanent],");
832 if (!printed_something)
836 void __symbol_put(const char *symbol)
838 struct module *owner;
841 if (!find_symbol(symbol, &owner, NULL, true, false))
846 EXPORT_SYMBOL(__symbol_put);
848 /* Note this assumes addr is a function, which it currently always is. */
849 void symbol_put_addr(void *addr)
851 struct module *modaddr;
852 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
854 if (core_kernel_text(a))
857 /* module_text_address is safe here: we're supposed to have reference
858 * to module from symbol_get, so it can't go away. */
859 modaddr = __module_text_address(a);
863 EXPORT_SYMBOL_GPL(symbol_put_addr);
865 static ssize_t show_refcnt(struct module_attribute *mattr,
866 struct module *mod, char *buffer)
868 return sprintf(buffer, "%u\n", module_refcount(mod));
871 static struct module_attribute refcnt = {
872 .attr = { .name = "refcnt", .mode = 0444 },
876 void module_put(struct module *module)
880 smp_wmb(); /* see comment in module_refcount */
881 __this_cpu_inc(module->refptr->decs);
883 trace_module_put(module, _RET_IP_);
884 /* Maybe they're waiting for us to drop reference? */
885 if (unlikely(!module_is_live(module)))
886 wake_up_process(module->waiter);
890 EXPORT_SYMBOL(module_put);
892 #else /* !CONFIG_MODULE_UNLOAD */
893 static inline void print_unload_info(struct seq_file *m, struct module *mod)
895 /* We don't know the usage count, or what modules are using. */
896 seq_printf(m, " - -");
899 static inline void module_unload_free(struct module *mod)
903 int ref_module(struct module *a, struct module *b)
905 return strong_try_module_get(b);
907 EXPORT_SYMBOL_GPL(ref_module);
909 static inline int module_unload_init(struct module *mod)
913 #endif /* CONFIG_MODULE_UNLOAD */
915 static ssize_t show_initstate(struct module_attribute *mattr,
916 struct module *mod, char *buffer)
918 const char *state = "unknown";
920 switch (mod->state) {
921 case MODULE_STATE_LIVE:
924 case MODULE_STATE_COMING:
927 case MODULE_STATE_GOING:
931 return sprintf(buffer, "%s\n", state);
934 static struct module_attribute initstate = {
935 .attr = { .name = "initstate", .mode = 0444 },
936 .show = show_initstate,
939 static struct module_attribute *modinfo_attrs[] = {
943 #ifdef CONFIG_MODULE_UNLOAD
949 static const char vermagic[] = VERMAGIC_STRING;
951 static int try_to_force_load(struct module *mod, const char *reason)
953 #ifdef CONFIG_MODULE_FORCE_LOAD
954 if (!test_taint(TAINT_FORCED_MODULE))
955 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
957 add_taint_module(mod, TAINT_FORCED_MODULE);
964 #ifdef CONFIG_MODVERSIONS
965 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
966 static unsigned long maybe_relocated(unsigned long crc,
967 const struct module *crc_owner)
969 #ifdef ARCH_RELOCATES_KCRCTAB
970 if (crc_owner == NULL)
971 return crc - (unsigned long)reloc_start;
976 static int check_version(Elf_Shdr *sechdrs,
977 unsigned int versindex,
980 const unsigned long *crc,
981 const struct module *crc_owner)
983 unsigned int i, num_versions;
984 struct modversion_info *versions;
986 /* Exporting module didn't supply crcs? OK, we're already tainted. */
990 /* No versions at all? modprobe --force does this. */
992 return try_to_force_load(mod, symname) == 0;
994 versions = (void *) sechdrs[versindex].sh_addr;
995 num_versions = sechdrs[versindex].sh_size
996 / sizeof(struct modversion_info);
998 for (i = 0; i < num_versions; i++) {
999 if (strcmp(versions[i].name, symname) != 0)
1002 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
1004 DEBUGP("Found checksum %lX vs module %lX\n",
1005 maybe_relocated(*crc, crc_owner), versions[i].crc);
1009 printk(KERN_WARNING "%s: no symbol version for %s\n",
1010 mod->name, symname);
1014 printk("%s: disagrees about version of symbol %s\n",
1015 mod->name, symname);
1019 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1020 unsigned int versindex,
1023 const unsigned long *crc;
1025 /* Since this should be found in kernel (which can't be removed),
1026 * no locking is necessary. */
1027 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1030 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1034 /* First part is kernel version, which we ignore if module has crcs. */
1035 static inline int same_magic(const char *amagic, const char *bmagic,
1039 amagic += strcspn(amagic, " ");
1040 bmagic += strcspn(bmagic, " ");
1042 return strcmp(amagic, bmagic) == 0;
1045 static inline int check_version(Elf_Shdr *sechdrs,
1046 unsigned int versindex,
1047 const char *symname,
1049 const unsigned long *crc,
1050 const struct module *crc_owner)
1055 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1056 unsigned int versindex,
1062 static inline int same_magic(const char *amagic, const char *bmagic,
1065 return strcmp(amagic, bmagic) == 0;
1067 #endif /* CONFIG_MODVERSIONS */
1069 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1070 static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
1071 unsigned int versindex,
1076 struct module *owner;
1077 const struct kernel_symbol *sym;
1078 const unsigned long *crc;
1081 mutex_lock(&module_mutex);
1082 sym = find_symbol(name, &owner, &crc,
1083 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1087 if (!check_version(sechdrs, versindex, name, mod, crc, owner)) {
1088 sym = ERR_PTR(-EINVAL);
1092 err = ref_module(mod, owner);
1099 /* We must make copy under the lock if we failed to get ref. */
1100 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1102 mutex_unlock(&module_mutex);
1106 static const struct kernel_symbol *resolve_symbol_wait(Elf_Shdr *sechdrs,
1107 unsigned int versindex,
1111 const struct kernel_symbol *ksym;
1112 char ownername[MODULE_NAME_LEN];
1114 if (wait_event_interruptible_timeout(module_wq,
1115 !IS_ERR(ksym = resolve_symbol(sechdrs, versindex, name,
1117 PTR_ERR(ksym) != -EBUSY,
1119 printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
1120 mod->name, ownername);
1126 * /sys/module/foo/sections stuff
1127 * J. Corbet <corbet@lwn.net>
1131 #ifdef CONFIG_KALLSYMS
1132 static inline bool sect_empty(const Elf_Shdr *sect)
1134 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1137 struct module_sect_attr
1139 struct module_attribute mattr;
1141 unsigned long address;
1144 struct module_sect_attrs
1146 struct attribute_group grp;
1147 unsigned int nsections;
1148 struct module_sect_attr attrs[0];
1151 static ssize_t module_sect_show(struct module_attribute *mattr,
1152 struct module *mod, char *buf)
1154 struct module_sect_attr *sattr =
1155 container_of(mattr, struct module_sect_attr, mattr);
1156 return sprintf(buf, "0x%lx\n", sattr->address);
1159 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1161 unsigned int section;
1163 for (section = 0; section < sect_attrs->nsections; section++)
1164 kfree(sect_attrs->attrs[section].name);
1168 static void add_sect_attrs(struct module *mod, const struct load_info *info)
1170 unsigned int nloaded = 0, i, size[2];
1171 struct module_sect_attrs *sect_attrs;
1172 struct module_sect_attr *sattr;
1173 struct attribute **gattr;
1175 /* Count loaded sections and allocate structures */
1176 for (i = 0; i < info->hdr->e_shnum; i++)
1177 if (!sect_empty(&info->sechdrs[i]))
1179 size[0] = ALIGN(sizeof(*sect_attrs)
1180 + nloaded * sizeof(sect_attrs->attrs[0]),
1181 sizeof(sect_attrs->grp.attrs[0]));
1182 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1183 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1184 if (sect_attrs == NULL)
1187 /* Setup section attributes. */
1188 sect_attrs->grp.name = "sections";
1189 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1191 sect_attrs->nsections = 0;
1192 sattr = §_attrs->attrs[0];
1193 gattr = §_attrs->grp.attrs[0];
1194 for (i = 0; i < info->hdr->e_shnum; i++) {
1195 Elf_Shdr *sec = &info->sechdrs[i];
1196 if (sect_empty(sec))
1198 sattr->address = sec->sh_addr;
1199 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1201 if (sattr->name == NULL)
1203 sect_attrs->nsections++;
1204 sysfs_attr_init(&sattr->mattr.attr);
1205 sattr->mattr.show = module_sect_show;
1206 sattr->mattr.store = NULL;
1207 sattr->mattr.attr.name = sattr->name;
1208 sattr->mattr.attr.mode = S_IRUGO;
1209 *(gattr++) = &(sattr++)->mattr.attr;
1213 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1216 mod->sect_attrs = sect_attrs;
1219 free_sect_attrs(sect_attrs);
1222 static void remove_sect_attrs(struct module *mod)
1224 if (mod->sect_attrs) {
1225 sysfs_remove_group(&mod->mkobj.kobj,
1226 &mod->sect_attrs->grp);
1227 /* We are positive that no one is using any sect attrs
1228 * at this point. Deallocate immediately. */
1229 free_sect_attrs(mod->sect_attrs);
1230 mod->sect_attrs = NULL;
1235 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1238 struct module_notes_attrs {
1239 struct kobject *dir;
1241 struct bin_attribute attrs[0];
1244 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1245 struct bin_attribute *bin_attr,
1246 char *buf, loff_t pos, size_t count)
1249 * The caller checked the pos and count against our size.
1251 memcpy(buf, bin_attr->private + pos, count);
1255 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1258 if (notes_attrs->dir) {
1260 sysfs_remove_bin_file(notes_attrs->dir,
1261 ¬es_attrs->attrs[i]);
1262 kobject_put(notes_attrs->dir);
1267 static void add_notes_attrs(struct module *mod, const struct load_info *info)
1269 unsigned int notes, loaded, i;
1270 struct module_notes_attrs *notes_attrs;
1271 struct bin_attribute *nattr;
1273 /* failed to create section attributes, so can't create notes */
1274 if (!mod->sect_attrs)
1277 /* Count notes sections and allocate structures. */
1279 for (i = 0; i < info->hdr->e_shnum; i++)
1280 if (!sect_empty(&info->sechdrs[i]) &&
1281 (info->sechdrs[i].sh_type == SHT_NOTE))
1287 notes_attrs = kzalloc(sizeof(*notes_attrs)
1288 + notes * sizeof(notes_attrs->attrs[0]),
1290 if (notes_attrs == NULL)
1293 notes_attrs->notes = notes;
1294 nattr = ¬es_attrs->attrs[0];
1295 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1296 if (sect_empty(&info->sechdrs[i]))
1298 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1299 sysfs_bin_attr_init(nattr);
1300 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1301 nattr->attr.mode = S_IRUGO;
1302 nattr->size = info->sechdrs[i].sh_size;
1303 nattr->private = (void *) info->sechdrs[i].sh_addr;
1304 nattr->read = module_notes_read;
1310 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1311 if (!notes_attrs->dir)
1314 for (i = 0; i < notes; ++i)
1315 if (sysfs_create_bin_file(notes_attrs->dir,
1316 ¬es_attrs->attrs[i]))
1319 mod->notes_attrs = notes_attrs;
1323 free_notes_attrs(notes_attrs, i);
1326 static void remove_notes_attrs(struct module *mod)
1328 if (mod->notes_attrs)
1329 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1334 static inline void add_sect_attrs(struct module *mod,
1335 const struct load_info *info)
1339 static inline void remove_sect_attrs(struct module *mod)
1343 static inline void add_notes_attrs(struct module *mod,
1344 const struct load_info *info)
1348 static inline void remove_notes_attrs(struct module *mod)
1351 #endif /* CONFIG_KALLSYMS */
1353 static void add_usage_links(struct module *mod)
1355 #ifdef CONFIG_MODULE_UNLOAD
1356 struct module_use *use;
1359 mutex_lock(&module_mutex);
1360 list_for_each_entry(use, &mod->target_list, target_list) {
1361 nowarn = sysfs_create_link(use->target->holders_dir,
1362 &mod->mkobj.kobj, mod->name);
1364 mutex_unlock(&module_mutex);
1368 static void del_usage_links(struct module *mod)
1370 #ifdef CONFIG_MODULE_UNLOAD
1371 struct module_use *use;
1373 mutex_lock(&module_mutex);
1374 list_for_each_entry(use, &mod->target_list, target_list)
1375 sysfs_remove_link(use->target->holders_dir, mod->name);
1376 mutex_unlock(&module_mutex);
1380 static int module_add_modinfo_attrs(struct module *mod)
1382 struct module_attribute *attr;
1383 struct module_attribute *temp_attr;
1387 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1388 (ARRAY_SIZE(modinfo_attrs) + 1)),
1390 if (!mod->modinfo_attrs)
1393 temp_attr = mod->modinfo_attrs;
1394 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1396 (attr->test && attr->test(mod))) {
1397 memcpy(temp_attr, attr, sizeof(*temp_attr));
1398 sysfs_attr_init(&temp_attr->attr);
1399 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1406 static void module_remove_modinfo_attrs(struct module *mod)
1408 struct module_attribute *attr;
1411 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1412 /* pick a field to test for end of list */
1413 if (!attr->attr.name)
1415 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1419 kfree(mod->modinfo_attrs);
1422 static int mod_sysfs_init(struct module *mod)
1425 struct kobject *kobj;
1427 if (!module_sysfs_initialized) {
1428 printk(KERN_ERR "%s: module sysfs not initialized\n",
1434 kobj = kset_find_obj(module_kset, mod->name);
1436 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1442 mod->mkobj.mod = mod;
1444 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1445 mod->mkobj.kobj.kset = module_kset;
1446 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1449 kobject_put(&mod->mkobj.kobj);
1451 /* delay uevent until full sysfs population */
1456 static int mod_sysfs_setup(struct module *mod,
1457 const struct load_info *info,
1458 struct kernel_param *kparam,
1459 unsigned int num_params)
1463 err = mod_sysfs_init(mod);
1467 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1468 if (!mod->holders_dir) {
1473 err = module_param_sysfs_setup(mod, kparam, num_params);
1475 goto out_unreg_holders;
1477 err = module_add_modinfo_attrs(mod);
1479 goto out_unreg_param;
1481 add_usage_links(mod);
1482 add_sect_attrs(mod, info);
1483 add_notes_attrs(mod, info);
1485 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1489 module_param_sysfs_remove(mod);
1491 kobject_put(mod->holders_dir);
1493 kobject_put(&mod->mkobj.kobj);
1498 static void mod_sysfs_fini(struct module *mod)
1500 remove_notes_attrs(mod);
1501 remove_sect_attrs(mod);
1502 kobject_put(&mod->mkobj.kobj);
1505 #else /* !CONFIG_SYSFS */
1507 static int mod_sysfs_setup(struct module *mod,
1508 const struct load_info *info,
1509 struct kernel_param *kparam,
1510 unsigned int num_params)
1515 static void mod_sysfs_fini(struct module *mod)
1519 static void module_remove_modinfo_attrs(struct module *mod)
1523 static void del_usage_links(struct module *mod)
1527 #endif /* CONFIG_SYSFS */
1529 static void mod_sysfs_teardown(struct module *mod)
1531 del_usage_links(mod);
1532 module_remove_modinfo_attrs(mod);
1533 module_param_sysfs_remove(mod);
1534 kobject_put(mod->mkobj.drivers_dir);
1535 kobject_put(mod->holders_dir);
1536 mod_sysfs_fini(mod);
1540 * unlink the module with the whole machine is stopped with interrupts off
1541 * - this defends against kallsyms not taking locks
1543 static int __unlink_module(void *_mod)
1545 struct module *mod = _mod;
1546 list_del(&mod->list);
1550 /* Free a module, remove from lists, etc. */
1551 static void free_module(struct module *mod)
1553 trace_module_free(mod);
1555 /* Delete from various lists */
1556 mutex_lock(&module_mutex);
1557 stop_machine(__unlink_module, mod, NULL);
1558 mutex_unlock(&module_mutex);
1559 mod_sysfs_teardown(mod);
1561 /* Remove dynamic debug info */
1562 ddebug_remove_module(mod->name);
1564 /* Arch-specific cleanup. */
1565 module_arch_cleanup(mod);
1567 /* Module unload stuff */
1568 module_unload_free(mod);
1570 /* Free any allocated parameters. */
1571 destroy_params(mod->kp, mod->num_kp);
1573 /* This may be NULL, but that's OK */
1574 module_free(mod, mod->module_init);
1576 percpu_modfree(mod);
1578 /* Free lock-classes: */
1579 lockdep_free_key_range(mod->module_core, mod->core_size);
1581 /* Finally, free the core (containing the module structure) */
1582 module_free(mod, mod->module_core);
1585 update_protections(current->mm);
1589 void *__symbol_get(const char *symbol)
1591 struct module *owner;
1592 const struct kernel_symbol *sym;
1595 sym = find_symbol(symbol, &owner, NULL, true, true);
1596 if (sym && strong_try_module_get(owner))
1600 return sym ? (void *)sym->value : NULL;
1602 EXPORT_SYMBOL_GPL(__symbol_get);
1605 * Ensure that an exported symbol [global namespace] does not already exist
1606 * in the kernel or in some other module's exported symbol table.
1608 * You must hold the module_mutex.
1610 static int verify_export_symbols(struct module *mod)
1613 struct module *owner;
1614 const struct kernel_symbol *s;
1616 const struct kernel_symbol *sym;
1619 { mod->syms, mod->num_syms },
1620 { mod->gpl_syms, mod->num_gpl_syms },
1621 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1622 #ifdef CONFIG_UNUSED_SYMBOLS
1623 { mod->unused_syms, mod->num_unused_syms },
1624 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1628 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1629 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1630 if (find_symbol(s->name, &owner, NULL, true, false)) {
1632 "%s: exports duplicate symbol %s"
1634 mod->name, s->name, module_name(owner));
1642 /* Change all symbols so that st_value encodes the pointer directly. */
1643 static int simplify_symbols(Elf_Shdr *sechdrs,
1644 unsigned int symindex,
1646 unsigned int versindex,
1647 unsigned int pcpuindex,
1650 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1651 unsigned long secbase;
1652 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1654 const struct kernel_symbol *ksym;
1656 for (i = 1; i < n; i++) {
1657 switch (sym[i].st_shndx) {
1659 /* We compiled with -fno-common. These are not
1660 supposed to happen. */
1661 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1662 printk("%s: please compile with -fno-common\n",
1668 /* Don't need to do anything */
1669 DEBUGP("Absolute symbol: 0x%08lx\n",
1670 (long)sym[i].st_value);
1674 ksym = resolve_symbol_wait(sechdrs, versindex,
1675 strtab + sym[i].st_name,
1677 /* Ok if resolved. */
1678 if (ksym && !IS_ERR(ksym)) {
1679 sym[i].st_value = ksym->value;
1684 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1687 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
1688 mod->name, strtab + sym[i].st_name,
1690 ret = PTR_ERR(ksym) ?: -ENOENT;
1694 /* Divert to percpu allocation if a percpu var. */
1695 if (sym[i].st_shndx == pcpuindex)
1696 secbase = (unsigned long)mod_percpu(mod);
1698 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1699 sym[i].st_value += secbase;
1707 static int apply_relocations(struct module *mod,
1710 unsigned int symindex,
1711 unsigned int strindex)
1716 /* Now do relocations. */
1717 for (i = 1; i < hdr->e_shnum; i++) {
1718 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1719 unsigned int info = sechdrs[i].sh_info;
1721 /* Not a valid relocation section? */
1722 if (info >= hdr->e_shnum)
1725 /* Don't bother with non-allocated sections */
1726 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1729 if (sechdrs[i].sh_type == SHT_REL)
1730 err = apply_relocate(sechdrs, strtab, symindex, i, mod);
1731 else if (sechdrs[i].sh_type == SHT_RELA)
1732 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1740 /* Additional bytes needed by arch in front of individual sections */
1741 unsigned int __weak arch_mod_section_prepend(struct module *mod,
1742 unsigned int section)
1744 /* default implementation just returns zero */
1748 /* Update size with this section: return offset. */
1749 static long get_offset(struct module *mod, unsigned int *size,
1750 Elf_Shdr *sechdr, unsigned int section)
1754 *size += arch_mod_section_prepend(mod, section);
1755 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1756 *size = ret + sechdr->sh_size;
1760 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1761 might -- code, read-only data, read-write data, small data. Tally
1762 sizes, and place the offsets into sh_entsize fields: high bit means it
1764 static void layout_sections(struct module *mod,
1765 const Elf_Ehdr *hdr,
1767 const char *secstrings)
1769 static unsigned long const masks[][2] = {
1770 /* NOTE: all executable code must be the first section
1771 * in this array; otherwise modify the text_size
1772 * finder in the two loops below */
1773 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1774 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1775 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1776 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1780 for (i = 0; i < hdr->e_shnum; i++)
1781 sechdrs[i].sh_entsize = ~0UL;
1783 DEBUGP("Core section allocation order:\n");
1784 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1785 for (i = 0; i < hdr->e_shnum; ++i) {
1786 Elf_Shdr *s = &sechdrs[i];
1788 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1789 || (s->sh_flags & masks[m][1])
1790 || s->sh_entsize != ~0UL
1791 || strstarts(secstrings + s->sh_name, ".init"))
1793 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1794 DEBUGP("\t%s\n", secstrings + s->sh_name);
1797 mod->core_text_size = mod->core_size;
1800 DEBUGP("Init section allocation order:\n");
1801 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1802 for (i = 0; i < hdr->e_shnum; ++i) {
1803 Elf_Shdr *s = &sechdrs[i];
1805 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1806 || (s->sh_flags & masks[m][1])
1807 || s->sh_entsize != ~0UL
1808 || !strstarts(secstrings + s->sh_name, ".init"))
1810 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1811 | INIT_OFFSET_MASK);
1812 DEBUGP("\t%s\n", secstrings + s->sh_name);
1815 mod->init_text_size = mod->init_size;
1819 static void set_license(struct module *mod, const char *license)
1822 license = "unspecified";
1824 if (!license_is_gpl_compatible(license)) {
1825 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1826 printk(KERN_WARNING "%s: module license '%s' taints "
1827 "kernel.\n", mod->name, license);
1828 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1832 /* Parse tag=value strings from .modinfo section */
1833 static char *next_string(char *string, unsigned long *secsize)
1835 /* Skip non-zero chars */
1838 if ((*secsize)-- <= 1)
1842 /* Skip any zero padding. */
1843 while (!string[0]) {
1845 if ((*secsize)-- <= 1)
1851 static char *get_modinfo(const Elf_Shdr *sechdrs,
1856 unsigned int taglen = strlen(tag);
1857 unsigned long size = sechdrs[info].sh_size;
1859 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1860 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1861 return p + taglen + 1;
1866 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1867 unsigned int infoindex)
1869 struct module_attribute *attr;
1872 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1875 get_modinfo(sechdrs,
1881 static void free_modinfo(struct module *mod)
1883 struct module_attribute *attr;
1886 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1892 #ifdef CONFIG_KALLSYMS
1894 /* lookup symbol in given range of kernel_symbols */
1895 static const struct kernel_symbol *lookup_symbol(const char *name,
1896 const struct kernel_symbol *start,
1897 const struct kernel_symbol *stop)
1899 const struct kernel_symbol *ks = start;
1900 for (; ks < stop; ks++)
1901 if (strcmp(ks->name, name) == 0)
1906 static int is_exported(const char *name, unsigned long value,
1907 const struct module *mod)
1909 const struct kernel_symbol *ks;
1911 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1913 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1914 return ks != NULL && ks->value == value;
1918 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
1920 const Elf_Shdr *sechdrs = info->sechdrs;
1922 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1923 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1928 if (sym->st_shndx == SHN_UNDEF)
1930 if (sym->st_shndx == SHN_ABS)
1932 if (sym->st_shndx >= SHN_LORESERVE)
1934 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1936 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1937 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1938 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1940 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1945 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1946 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1951 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
1958 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1961 const Elf_Shdr *sec;
1963 if (src->st_shndx == SHN_UNDEF
1964 || src->st_shndx >= shnum
1968 sec = sechdrs + src->st_shndx;
1969 if (!(sec->sh_flags & SHF_ALLOC)
1970 #ifndef CONFIG_KALLSYMS_ALL
1971 || !(sec->sh_flags & SHF_EXECINSTR)
1973 || (sec->sh_entsize & INIT_OFFSET_MASK))
1979 static unsigned long layout_symtab(struct module *mod,
1981 unsigned int symindex,
1982 unsigned int strindex,
1983 const Elf_Ehdr *hdr,
1984 const char *secstrings,
1985 unsigned long *pstroffs,
1986 unsigned long *strmap)
1988 unsigned long symoffs;
1989 Elf_Shdr *symsect = sechdrs + symindex;
1990 Elf_Shdr *strsect = sechdrs + strindex;
1993 unsigned int i, nsrc, ndst;
1995 /* Put symbol section at end of init part of module. */
1996 symsect->sh_flags |= SHF_ALLOC;
1997 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1998 symindex) | INIT_OFFSET_MASK;
1999 DEBUGP("\t%s\n", secstrings + symsect->sh_name);
2001 src = (void *)hdr + symsect->sh_offset;
2002 nsrc = symsect->sh_size / sizeof(*src);
2003 strtab = (void *)hdr + strsect->sh_offset;
2004 for (ndst = i = 1; i < nsrc; ++i, ++src)
2005 if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
2006 unsigned int j = src->st_name;
2008 while(!__test_and_set_bit(j, strmap) && strtab[j])
2013 /* Append room for core symbols at end of core part. */
2014 symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
2015 mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
2017 /* Put string table section at end of init part of module. */
2018 strsect->sh_flags |= SHF_ALLOC;
2019 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
2020 strindex) | INIT_OFFSET_MASK;
2021 DEBUGP("\t%s\n", secstrings + strsect->sh_name);
2023 /* Append room for core symbols' strings at end of core part. */
2024 *pstroffs = mod->core_size;
2025 __set_bit(0, strmap);
2026 mod->core_size += bitmap_weight(strmap, strsect->sh_size);
2031 static void add_kallsyms(struct module *mod, struct load_info *info)
2033 unsigned int i, ndst;
2037 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2039 mod->symtab = (void *)symsec->sh_addr;
2040 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2041 /* Make sure we get permanent strtab: don't use info->strtab. */
2042 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2044 /* Set types up while we still have access to sections. */
2045 for (i = 0; i < mod->num_symtab; i++)
2046 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
2048 mod->core_symtab = dst = mod->module_core + info->symoffs;
2051 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
2052 if (!is_core_symbol(src, info->sechdrs, info->hdr->e_shnum))
2055 dst[ndst].st_name = bitmap_weight(info->strmap,
2059 mod->core_num_syms = ndst;
2061 mod->core_strtab = s = mod->module_core + info->stroffs;
2062 for (*s = 0, i = 1; i < info->sechdrs[info->index.str].sh_size; ++i)
2063 if (test_bit(i, info->strmap))
2064 *++s = mod->strtab[i];
2067 static inline unsigned long layout_symtab(struct module *mod,
2069 unsigned int symindex,
2070 unsigned int strindex,
2071 const Elf_Ehdr *hdr,
2072 const char *secstrings,
2073 unsigned long *pstroffs,
2074 unsigned long *strmap)
2079 static void add_kallsyms(struct module *mod, struct load_info *info)
2082 #endif /* CONFIG_KALLSYMS */
2084 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2086 #ifdef CONFIG_DYNAMIC_DEBUG
2087 if (ddebug_add_module(debug, num, debug->modname))
2088 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2093 static void dynamic_debug_remove(struct _ddebug *debug)
2096 ddebug_remove_module(debug->modname);
2099 static void *module_alloc_update_bounds(unsigned long size)
2101 void *ret = module_alloc(size);
2104 mutex_lock(&module_mutex);
2105 /* Update module bounds. */
2106 if ((unsigned long)ret < module_addr_min)
2107 module_addr_min = (unsigned long)ret;
2108 if ((unsigned long)ret + size > module_addr_max)
2109 module_addr_max = (unsigned long)ret + size;
2110 mutex_unlock(&module_mutex);
2115 #ifdef CONFIG_DEBUG_KMEMLEAK
2116 static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2117 const Elf_Shdr *sechdrs,
2118 const char *secstrings)
2122 /* only scan the sections containing data */
2123 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2125 for (i = 1; i < hdr->e_shnum; i++) {
2126 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2128 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
2129 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
2132 kmemleak_scan_area((void *)sechdrs[i].sh_addr,
2133 sechdrs[i].sh_size, GFP_KERNEL);
2137 static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2139 const char *secstrings)
2144 /* Sets info->hdr, info->len and info->args. */
2145 static int copy_and_check(struct load_info *info,
2146 const void __user *umod, unsigned long len,
2147 const char __user *uargs)
2152 if (len < sizeof(*hdr))
2155 /* Suck in entire file: we'll want most of it. */
2156 /* vmalloc barfs on "unusual" numbers. Check here */
2157 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
2160 if (copy_from_user(hdr, umod, len) != 0) {
2165 /* Sanity checks against insmoding binaries or wrong arch,
2166 weird elf version */
2167 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
2168 || hdr->e_type != ET_REL
2169 || !elf_check_arch(hdr)
2170 || hdr->e_shentsize != sizeof(Elf_Shdr)) {
2175 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
2180 /* Now copy in args */
2181 info->args = strndup_user(uargs, ~0UL >> 1);
2182 if (IS_ERR(info->args)) {
2183 err = PTR_ERR(info->args);
2196 static void free_copy(struct load_info *info)
2202 static int rewrite_section_headers(struct load_info *info)
2206 /* This should always be true, but let's be sure. */
2207 info->sechdrs[0].sh_addr = 0;
2209 for (i = 1; i < info->hdr->e_shnum; i++) {
2210 Elf_Shdr *shdr = &info->sechdrs[i];
2211 if (shdr->sh_type != SHT_NOBITS
2212 && info->len < shdr->sh_offset + shdr->sh_size) {
2213 printk(KERN_ERR "Module len %lu truncated\n",
2218 /* Mark all sections sh_addr with their address in the
2220 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2222 #ifndef CONFIG_MODULE_UNLOAD
2223 /* Don't load .exit sections */
2224 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2225 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2229 /* Track but don't keep modinfo and version sections. */
2230 info->index.vers = find_sec(info->hdr, info->sechdrs, info->secstrings, "__versions");
2231 info->index.info = find_sec(info->hdr, info->sechdrs, info->secstrings, ".modinfo");
2232 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2233 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2238 * Set up our basic convenience variables (pointers to section headers,
2239 * search for module section index etc), and do some basic section
2242 * Return the temporary module pointer (we'll replace it with the final
2243 * one when we move the module sections around).
2245 static struct module *setup_load_info(struct load_info *info)
2251 /* Set up the convenience variables */
2252 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2253 info->secstrings = (void *)info->hdr
2254 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2256 err = rewrite_section_headers(info);
2258 return ERR_PTR(err);
2260 /* Find internal symbols and strings. */
2261 for (i = 1; i < info->hdr->e_shnum; i++) {
2262 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2263 info->index.sym = i;
2264 info->index.str = info->sechdrs[i].sh_link;
2265 info->strtab = (char *)info->hdr
2266 + info->sechdrs[info->index.str].sh_offset;
2271 info->index.mod = find_sec(info->hdr, info->sechdrs, info->secstrings,
2272 ".gnu.linkonce.this_module");
2273 if (!info->index.mod) {
2274 printk(KERN_WARNING "No module found in object\n");
2275 return ERR_PTR(-ENOEXEC);
2277 /* This is temporary: point mod into copy of data. */
2278 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2280 if (info->index.sym == 0) {
2281 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2283 return ERR_PTR(-ENOEXEC);
2286 info->index.pcpu = find_pcpusec(info->hdr, info->sechdrs, info->secstrings);
2288 /* Check module struct version now, before we try to use module. */
2289 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2290 return ERR_PTR(-ENOEXEC);
2295 static int check_modinfo(struct module *mod,
2296 const Elf_Shdr *sechdrs,
2297 unsigned int infoindex, unsigned int versindex)
2299 const char *modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2302 /* This is allowed: modprobe --force will invalidate it. */
2304 err = try_to_force_load(mod, "bad vermagic");
2307 } else if (!same_magic(modmagic, vermagic, versindex)) {
2308 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2309 mod->name, modmagic, vermagic);
2313 if (get_modinfo(sechdrs, infoindex, "staging")) {
2314 add_taint_module(mod, TAINT_CRAP);
2315 printk(KERN_WARNING "%s: module is from the staging directory,"
2316 " the quality is unknown, you have been warned.\n",
2320 /* Set up license info based on the info section */
2321 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2326 static void find_module_sections(struct module *mod, Elf_Ehdr *hdr,
2327 Elf_Shdr *sechdrs, const char *secstrings)
2329 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2330 sizeof(*mod->kp), &mod->num_kp);
2331 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2332 sizeof(*mod->syms), &mod->num_syms);
2333 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2334 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2335 sizeof(*mod->gpl_syms),
2336 &mod->num_gpl_syms);
2337 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2338 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2339 "__ksymtab_gpl_future",
2340 sizeof(*mod->gpl_future_syms),
2341 &mod->num_gpl_future_syms);
2342 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2343 "__kcrctab_gpl_future");
2345 #ifdef CONFIG_UNUSED_SYMBOLS
2346 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2348 sizeof(*mod->unused_syms),
2349 &mod->num_unused_syms);
2350 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2351 "__kcrctab_unused");
2352 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2353 "__ksymtab_unused_gpl",
2354 sizeof(*mod->unused_gpl_syms),
2355 &mod->num_unused_gpl_syms);
2356 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2357 "__kcrctab_unused_gpl");
2359 #ifdef CONFIG_CONSTRUCTORS
2360 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2361 sizeof(*mod->ctors), &mod->num_ctors);
2364 #ifdef CONFIG_TRACEPOINTS
2365 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2367 sizeof(*mod->tracepoints),
2368 &mod->num_tracepoints);
2370 #ifdef CONFIG_EVENT_TRACING
2371 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2373 sizeof(*mod->trace_events),
2374 &mod->num_trace_events);
2376 * This section contains pointers to allocated objects in the trace
2377 * code and not scanning it leads to false positives.
2379 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2380 mod->num_trace_events, GFP_KERNEL);
2382 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2383 /* sechdrs[0].sh_size is always zero */
2384 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2386 sizeof(*mod->ftrace_callsites),
2387 &mod->num_ftrace_callsites);
2390 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2391 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2395 static int move_module(struct module *mod,
2396 Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
2397 const char *secstrings, unsigned modindex)
2402 /* Do the allocs. */
2403 ptr = module_alloc_update_bounds(mod->core_size);
2405 * The pointer to this block is stored in the module structure
2406 * which is inside the block. Just mark it as not being a
2409 kmemleak_not_leak(ptr);
2413 memset(ptr, 0, mod->core_size);
2414 mod->module_core = ptr;
2416 ptr = module_alloc_update_bounds(mod->init_size);
2418 * The pointer to this block is stored in the module structure
2419 * which is inside the block. This block doesn't need to be
2420 * scanned as it contains data and code that will be freed
2421 * after the module is initialized.
2423 kmemleak_ignore(ptr);
2424 if (!ptr && mod->init_size) {
2425 module_free(mod, mod->module_core);
2428 memset(ptr, 0, mod->init_size);
2429 mod->module_init = ptr;
2431 /* Transfer each section which specifies SHF_ALLOC */
2432 DEBUGP("final section addresses:\n");
2433 for (i = 0; i < hdr->e_shnum; i++) {
2436 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2439 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2440 dest = mod->module_init
2441 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2443 dest = mod->module_core + sechdrs[i].sh_entsize;
2445 if (sechdrs[i].sh_type != SHT_NOBITS)
2446 memcpy(dest, (void *)sechdrs[i].sh_addr,
2447 sechdrs[i].sh_size);
2448 /* Update sh_addr to point to copy in image. */
2449 sechdrs[i].sh_addr = (unsigned long)dest;
2450 DEBUGP("\t0x%lx %s\n",
2451 sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2457 static int check_module_license_and_versions(struct module *mod,
2461 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2462 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2463 * using GPL-only symbols it needs.
2465 if (strcmp(mod->name, "ndiswrapper") == 0)
2466 add_taint(TAINT_PROPRIETARY_MODULE);
2468 /* driverloader was caught wrongly pretending to be under GPL */
2469 if (strcmp(mod->name, "driverloader") == 0)
2470 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2472 #ifdef CONFIG_MODVERSIONS
2473 if ((mod->num_syms && !mod->crcs)
2474 || (mod->num_gpl_syms && !mod->gpl_crcs)
2475 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2476 #ifdef CONFIG_UNUSED_SYMBOLS
2477 || (mod->num_unused_syms && !mod->unused_crcs)
2478 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2481 return try_to_force_load(mod,
2482 "no versions for exported symbols");
2488 static void flush_module_icache(const struct module *mod)
2490 mm_segment_t old_fs;
2492 /* flush the icache in correct context */
2497 * Flush the instruction cache, since we've played with text.
2498 * Do it before processing of module parameters, so the module
2499 * can provide parameter accessor functions of its own.
2501 if (mod->module_init)
2502 flush_icache_range((unsigned long)mod->module_init,
2503 (unsigned long)mod->module_init
2505 flush_icache_range((unsigned long)mod->module_core,
2506 (unsigned long)mod->module_core + mod->core_size);
2511 static struct module *layout_and_allocate(struct load_info *info)
2513 /* Module within temporary copy. */
2517 mod = setup_load_info(info);
2521 err = check_modinfo(mod, info->sechdrs, info->index.info, info->index.vers);
2523 return ERR_PTR(err);
2525 /* Allow arches to frob section contents and sizes. */
2526 err = module_frob_arch_sections(info->hdr, info->sechdrs, info->secstrings, mod);
2530 if (info->index.pcpu) {
2531 /* We have a special allocation for this section. */
2532 err = percpu_modalloc(mod, info->sechdrs[info->index.pcpu].sh_size,
2533 info->sechdrs[info->index.pcpu].sh_addralign);
2536 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
2539 /* Determine total sizes, and put offsets in sh_entsize. For now
2540 this is done generically; there doesn't appear to be any
2541 special cases for the architectures. */
2542 layout_sections(mod, info->hdr, info->sechdrs, info->secstrings);
2544 info->strmap = kzalloc(BITS_TO_LONGS(info->sechdrs[info->index.str].sh_size)
2545 * sizeof(long), GFP_KERNEL);
2546 if (!info->strmap) {
2550 info->symoffs = layout_symtab(mod, info->sechdrs, info->index.sym, info->index.str, info->hdr,
2551 info->secstrings, &info->stroffs, info->strmap);
2553 /* Allocate and move to the final place */
2554 err = move_module(mod, info->hdr, info->sechdrs, info->secstrings, info->index.mod);
2558 /* Module has been copied to its final place now: return it. */
2559 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2560 kmemleak_load_module(mod, info->hdr, info->sechdrs, info->secstrings);
2564 kfree(info->strmap);
2566 percpu_modfree(mod);
2569 return ERR_PTR(err);
2572 /* mod is no longer valid after this! */
2573 static void module_deallocate(struct module *mod, struct load_info *info)
2575 kfree(info->strmap);
2576 percpu_modfree(mod);
2577 module_free(mod, mod->module_init);
2578 module_free(mod, mod->module_core);
2581 /* Allocate and load the module: note that size of section 0 is always
2582 zero, and we rely on this for optional sections. */
2583 static noinline struct module *load_module(void __user *umod,
2585 const char __user *uargs)
2587 struct load_info info = { NULL, };
2590 struct _ddebug *debug = NULL;
2591 unsigned int num_debug = 0;
2593 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2596 /* Copy in the blobs from userspace, check they are vaguely sane. */
2597 err = copy_and_check(&info, umod, len, uargs);
2599 return ERR_PTR(err);
2601 /* Figure out module layout, and allocate all the memory. */
2602 mod = layout_and_allocate(&info);
2608 /* Now we've moved module, initialize linked lists, etc. */
2609 err = module_unload_init(mod);
2613 /* Now we've got everything in the final locations, we can
2614 * find optional sections. */
2615 find_module_sections(mod, info.hdr, info.sechdrs, info.secstrings);
2617 err = check_module_license_and_versions(mod, info.sechdrs);
2621 /* Set up MODINFO_ATTR fields */
2622 setup_modinfo(mod, info.sechdrs, info.index.info);
2624 /* Fix up syms, so that st_value is a pointer to location. */
2625 err = simplify_symbols(info.sechdrs, info.index.sym, info.strtab, info.index.vers, info.index.pcpu,
2630 err = apply_relocations(mod, info.hdr, info.sechdrs, info.index.sym, info.index.str);
2634 /* Set up and sort exception table */
2635 mod->extable = section_objs(info.hdr, info.sechdrs, info.secstrings, "__ex_table",
2636 sizeof(*mod->extable), &mod->num_exentries);
2637 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2639 /* Finally, copy percpu area over. */
2640 percpu_modcopy(mod, (void *)info.sechdrs[info.index.pcpu].sh_addr,
2641 info.sechdrs[info.index.pcpu].sh_size);
2643 add_kallsyms(mod, &info);
2646 debug = section_objs(info.hdr, info.sechdrs, info.secstrings, "__verbose",
2647 sizeof(*debug), &num_debug);
2649 err = module_finalize(info.hdr, info.sechdrs, mod);
2653 flush_module_icache(mod);
2655 mod->args = info.args;
2657 mod->state = MODULE_STATE_COMING;
2659 /* Now sew it into the lists so we can get lockdep and oops
2660 * info during argument parsing. Noone should access us, since
2661 * strong_try_module_get() will fail.
2662 * lockdep/oops can run asynchronous, so use the RCU list insertion
2663 * function to insert in a way safe to concurrent readers.
2664 * The mutex protects against concurrent writers.
2666 mutex_lock(&module_mutex);
2667 if (find_module(mod->name)) {
2673 dynamic_debug_setup(debug, num_debug);
2675 /* Find duplicate symbols */
2676 err = verify_export_symbols(mod);
2680 list_add_rcu(&mod->list, &modules);
2681 mutex_unlock(&module_mutex);
2683 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2687 err = mod_sysfs_setup(mod, &info, mod->kp, mod->num_kp);
2691 /* Get rid of temporary copy and strmap. */
2695 trace_module_load(mod);
2701 mutex_lock(&module_mutex);
2702 /* Unlink carefully: kallsyms could be walking list. */
2703 list_del_rcu(&mod->list);
2705 dynamic_debug_remove(debug);
2707 mutex_unlock(&module_mutex);
2708 synchronize_sched();
2709 module_arch_cleanup(mod);
2713 module_unload_free(mod);
2715 module_deallocate(mod, &info);
2718 return ERR_PTR(err);
2721 /* Call module constructors. */
2722 static void do_mod_ctors(struct module *mod)
2724 #ifdef CONFIG_CONSTRUCTORS
2727 for (i = 0; i < mod->num_ctors; i++)
2732 /* This is where the real work happens */
2733 SYSCALL_DEFINE3(init_module, void __user *, umod,
2734 unsigned long, len, const char __user *, uargs)
2739 /* Must have permission */
2740 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2743 /* Do all the hard work */
2744 mod = load_module(umod, len, uargs);
2746 return PTR_ERR(mod);
2748 blocking_notifier_call_chain(&module_notify_list,
2749 MODULE_STATE_COMING, mod);
2752 /* Start the module */
2753 if (mod->init != NULL)
2754 ret = do_one_initcall(mod->init);
2756 /* Init routine failed: abort. Try to protect us from
2757 buggy refcounters. */
2758 mod->state = MODULE_STATE_GOING;
2759 synchronize_sched();
2761 blocking_notifier_call_chain(&module_notify_list,
2762 MODULE_STATE_GOING, mod);
2764 wake_up(&module_wq);
2769 "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2770 "%s: loading module anyway...\n",
2771 __func__, mod->name, ret,
2776 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2777 mod->state = MODULE_STATE_LIVE;
2778 wake_up(&module_wq);
2779 blocking_notifier_call_chain(&module_notify_list,
2780 MODULE_STATE_LIVE, mod);
2782 /* We need to finish all async code before the module init sequence is done */
2783 async_synchronize_full();
2785 mutex_lock(&module_mutex);
2786 /* Drop initial reference. */
2788 trim_init_extable(mod);
2789 #ifdef CONFIG_KALLSYMS
2790 mod->num_symtab = mod->core_num_syms;
2791 mod->symtab = mod->core_symtab;
2792 mod->strtab = mod->core_strtab;
2794 module_free(mod, mod->module_init);
2795 mod->module_init = NULL;
2797 mod->init_text_size = 0;
2798 mutex_unlock(&module_mutex);
2803 static inline int within(unsigned long addr, void *start, unsigned long size)
2805 return ((void *)addr >= start && (void *)addr < start + size);
2808 #ifdef CONFIG_KALLSYMS
2810 * This ignores the intensely annoying "mapping symbols" found
2811 * in ARM ELF files: $a, $t and $d.
2813 static inline int is_arm_mapping_symbol(const char *str)
2815 return str[0] == '$' && strchr("atd", str[1])
2816 && (str[2] == '\0' || str[2] == '.');
2819 static const char *get_ksymbol(struct module *mod,
2821 unsigned long *size,
2822 unsigned long *offset)
2824 unsigned int i, best = 0;
2825 unsigned long nextval;
2827 /* At worse, next value is at end of module */
2828 if (within_module_init(addr, mod))
2829 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2831 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2833 /* Scan for closest preceeding symbol, and next symbol. (ELF
2834 starts real symbols at 1). */
2835 for (i = 1; i < mod->num_symtab; i++) {
2836 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2839 /* We ignore unnamed symbols: they're uninformative
2840 * and inserted at a whim. */
2841 if (mod->symtab[i].st_value <= addr
2842 && mod->symtab[i].st_value > mod->symtab[best].st_value
2843 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2844 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2846 if (mod->symtab[i].st_value > addr
2847 && mod->symtab[i].st_value < nextval
2848 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2849 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2850 nextval = mod->symtab[i].st_value;
2857 *size = nextval - mod->symtab[best].st_value;
2859 *offset = addr - mod->symtab[best].st_value;
2860 return mod->strtab + mod->symtab[best].st_name;
2863 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2864 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2865 const char *module_address_lookup(unsigned long addr,
2866 unsigned long *size,
2867 unsigned long *offset,
2872 const char *ret = NULL;
2875 list_for_each_entry_rcu(mod, &modules, list) {
2876 if (within_module_init(addr, mod) ||
2877 within_module_core(addr, mod)) {
2879 *modname = mod->name;
2880 ret = get_ksymbol(mod, addr, size, offset);
2884 /* Make a copy in here where it's safe */
2886 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2893 int lookup_module_symbol_name(unsigned long addr, char *symname)
2898 list_for_each_entry_rcu(mod, &modules, list) {
2899 if (within_module_init(addr, mod) ||
2900 within_module_core(addr, mod)) {
2903 sym = get_ksymbol(mod, addr, NULL, NULL);
2906 strlcpy(symname, sym, KSYM_NAME_LEN);
2916 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2917 unsigned long *offset, char *modname, char *name)
2922 list_for_each_entry_rcu(mod, &modules, list) {
2923 if (within_module_init(addr, mod) ||
2924 within_module_core(addr, mod)) {
2927 sym = get_ksymbol(mod, addr, size, offset);
2931 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2933 strlcpy(name, sym, KSYM_NAME_LEN);
2943 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2944 char *name, char *module_name, int *exported)
2949 list_for_each_entry_rcu(mod, &modules, list) {
2950 if (symnum < mod->num_symtab) {
2951 *value = mod->symtab[symnum].st_value;
2952 *type = mod->symtab[symnum].st_info;
2953 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2955 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2956 *exported = is_exported(name, *value, mod);
2960 symnum -= mod->num_symtab;
2966 static unsigned long mod_find_symname(struct module *mod, const char *name)
2970 for (i = 0; i < mod->num_symtab; i++)
2971 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2972 mod->symtab[i].st_info != 'U')
2973 return mod->symtab[i].st_value;
2977 /* Look for this name: can be of form module:name. */
2978 unsigned long module_kallsyms_lookup_name(const char *name)
2982 unsigned long ret = 0;
2984 /* Don't lock: we're in enough trouble already. */
2986 if ((colon = strchr(name, ':')) != NULL) {
2988 if ((mod = find_module(name)) != NULL)
2989 ret = mod_find_symname(mod, colon+1);
2992 list_for_each_entry_rcu(mod, &modules, list)
2993 if ((ret = mod_find_symname(mod, name)) != 0)
3000 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3001 struct module *, unsigned long),
3008 list_for_each_entry(mod, &modules, list) {
3009 for (i = 0; i < mod->num_symtab; i++) {
3010 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
3011 mod, mod->symtab[i].st_value);
3018 #endif /* CONFIG_KALLSYMS */
3020 static char *module_flags(struct module *mod, char *buf)
3025 mod->state == MODULE_STATE_GOING ||
3026 mod->state == MODULE_STATE_COMING) {
3028 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
3030 if (mod->taints & (1 << TAINT_FORCED_MODULE))
3032 if (mod->taints & (1 << TAINT_CRAP))
3035 * TAINT_FORCED_RMMOD: could be added.
3036 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
3040 /* Show a - for module-is-being-unloaded */
3041 if (mod->state == MODULE_STATE_GOING)
3043 /* Show a + for module-is-being-loaded */
3044 if (mod->state == MODULE_STATE_COMING)
3053 #ifdef CONFIG_PROC_FS
3054 /* Called by the /proc file system to return a list of modules. */
3055 static void *m_start(struct seq_file *m, loff_t *pos)
3057 mutex_lock(&module_mutex);
3058 return seq_list_start(&modules, *pos);
3061 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3063 return seq_list_next(p, &modules, pos);
3066 static void m_stop(struct seq_file *m, void *p)
3068 mutex_unlock(&module_mutex);
3071 static int m_show(struct seq_file *m, void *p)
3073 struct module *mod = list_entry(p, struct module, list);
3076 seq_printf(m, "%s %u",
3077 mod->name, mod->init_size + mod->core_size);
3078 print_unload_info(m, mod);
3080 /* Informative for users. */
3081 seq_printf(m, " %s",
3082 mod->state == MODULE_STATE_GOING ? "Unloading":
3083 mod->state == MODULE_STATE_COMING ? "Loading":
3085 /* Used by oprofile and other similar tools. */
3086 seq_printf(m, " 0x%p", mod->module_core);
3090 seq_printf(m, " %s", module_flags(mod, buf));
3092 seq_printf(m, "\n");
3096 /* Format: modulename size refcount deps address
3098 Where refcount is a number or -, and deps is a comma-separated list
3101 static const struct seq_operations modules_op = {
3108 static int modules_open(struct inode *inode, struct file *file)
3110 return seq_open(file, &modules_op);
3113 static const struct file_operations proc_modules_operations = {
3114 .open = modules_open,
3116 .llseek = seq_lseek,
3117 .release = seq_release,
3120 static int __init proc_modules_init(void)
3122 proc_create("modules", 0, NULL, &proc_modules_operations);
3125 module_init(proc_modules_init);
3128 /* Given an address, look for it in the module exception tables. */
3129 const struct exception_table_entry *search_module_extables(unsigned long addr)
3131 const struct exception_table_entry *e = NULL;
3135 list_for_each_entry_rcu(mod, &modules, list) {
3136 if (mod->num_exentries == 0)
3139 e = search_extable(mod->extable,
3140 mod->extable + mod->num_exentries - 1,
3147 /* Now, if we found one, we are running inside it now, hence
3148 we cannot unload the module, hence no refcnt needed. */
3153 * is_module_address - is this address inside a module?
3154 * @addr: the address to check.
3156 * See is_module_text_address() if you simply want to see if the address
3157 * is code (not data).
3159 bool is_module_address(unsigned long addr)
3164 ret = __module_address(addr) != NULL;
3171 * __module_address - get the module which contains an address.
3172 * @addr: the address.
3174 * Must be called with preempt disabled or module mutex held so that
3175 * module doesn't get freed during this.
3177 struct module *__module_address(unsigned long addr)
3181 if (addr < module_addr_min || addr > module_addr_max)
3184 list_for_each_entry_rcu(mod, &modules, list)
3185 if (within_module_core(addr, mod)
3186 || within_module_init(addr, mod))
3190 EXPORT_SYMBOL_GPL(__module_address);
3193 * is_module_text_address - is this address inside module code?
3194 * @addr: the address to check.
3196 * See is_module_address() if you simply want to see if the address is
3197 * anywhere in a module. See kernel_text_address() for testing if an
3198 * address corresponds to kernel or module code.
3200 bool is_module_text_address(unsigned long addr)
3205 ret = __module_text_address(addr) != NULL;
3212 * __module_text_address - get the module whose code contains an address.
3213 * @addr: the address.
3215 * Must be called with preempt disabled or module mutex held so that
3216 * module doesn't get freed during this.
3218 struct module *__module_text_address(unsigned long addr)
3220 struct module *mod = __module_address(addr);
3222 /* Make sure it's within the text section. */
3223 if (!within(addr, mod->module_init, mod->init_text_size)
3224 && !within(addr, mod->module_core, mod->core_text_size))
3229 EXPORT_SYMBOL_GPL(__module_text_address);
3231 /* Don't grab lock, we're oopsing. */
3232 void print_modules(void)
3237 printk(KERN_DEFAULT "Modules linked in:");
3238 /* Most callers should already have preempt disabled, but make sure */
3240 list_for_each_entry_rcu(mod, &modules, list)
3241 printk(" %s%s", mod->name, module_flags(mod, buf));
3243 if (last_unloaded_module[0])
3244 printk(" [last unloaded: %s]", last_unloaded_module);
3248 #ifdef CONFIG_MODVERSIONS
3249 /* Generate the signature for all relevant module structures here.
3250 * If these change, we don't want to try to parse the module. */
3251 void module_layout(struct module *mod,
3252 struct modversion_info *ver,
3253 struct kernel_param *kp,
3254 struct kernel_symbol *ks,
3255 struct tracepoint *tp)
3258 EXPORT_SYMBOL(module_layout);
3261 #ifdef CONFIG_TRACEPOINTS
3262 void module_update_tracepoints(void)
3266 mutex_lock(&module_mutex);
3267 list_for_each_entry(mod, &modules, list)
3269 tracepoint_update_probe_range(mod->tracepoints,
3270 mod->tracepoints + mod->num_tracepoints);
3271 mutex_unlock(&module_mutex);
3275 * Returns 0 if current not found.
3276 * Returns 1 if current found.
3278 int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3280 struct module *iter_mod;
3283 mutex_lock(&module_mutex);
3284 list_for_each_entry(iter_mod, &modules, list) {
3285 if (!iter_mod->taints) {
3287 * Sorted module list
3289 if (iter_mod < iter->module)
3291 else if (iter_mod > iter->module)
3292 iter->tracepoint = NULL;
3293 found = tracepoint_get_iter_range(&iter->tracepoint,
3294 iter_mod->tracepoints,
3295 iter_mod->tracepoints
3296 + iter_mod->num_tracepoints);
3298 iter->module = iter_mod;
3303 mutex_unlock(&module_mutex);