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_init(struct module *mod)
1512 static int mod_sysfs_setup(struct module *mod,
1513 const struct load_info *info,
1514 struct kernel_param *kparam,
1515 unsigned int num_params)
1520 static void mod_sysfs_fini(struct module *mod)
1524 static void del_usage_links(struct module *mod)
1528 #endif /* CONFIG_SYSFS */
1530 static void mod_kobject_remove(struct module *mod)
1532 del_usage_links(mod);
1533 module_remove_modinfo_attrs(mod);
1534 module_param_sysfs_remove(mod);
1535 kobject_put(mod->mkobj.drivers_dir);
1536 kobject_put(mod->holders_dir);
1537 mod_sysfs_fini(mod);
1541 * unlink the module with the whole machine is stopped with interrupts off
1542 * - this defends against kallsyms not taking locks
1544 static int __unlink_module(void *_mod)
1546 struct module *mod = _mod;
1547 list_del(&mod->list);
1551 /* Free a module, remove from lists, etc. */
1552 static void free_module(struct module *mod)
1554 trace_module_free(mod);
1556 /* Delete from various lists */
1557 mutex_lock(&module_mutex);
1558 stop_machine(__unlink_module, mod, NULL);
1559 mutex_unlock(&module_mutex);
1560 mod_kobject_remove(mod);
1562 /* Remove dynamic debug info */
1563 ddebug_remove_module(mod->name);
1565 /* Arch-specific cleanup. */
1566 module_arch_cleanup(mod);
1568 /* Module unload stuff */
1569 module_unload_free(mod);
1571 /* Free any allocated parameters. */
1572 destroy_params(mod->kp, mod->num_kp);
1574 /* This may be NULL, but that's OK */
1575 module_free(mod, mod->module_init);
1577 percpu_modfree(mod);
1579 /* Free lock-classes: */
1580 lockdep_free_key_range(mod->module_core, mod->core_size);
1582 /* Finally, free the core (containing the module structure) */
1583 module_free(mod, mod->module_core);
1586 update_protections(current->mm);
1590 void *__symbol_get(const char *symbol)
1592 struct module *owner;
1593 const struct kernel_symbol *sym;
1596 sym = find_symbol(symbol, &owner, NULL, true, true);
1597 if (sym && strong_try_module_get(owner))
1601 return sym ? (void *)sym->value : NULL;
1603 EXPORT_SYMBOL_GPL(__symbol_get);
1606 * Ensure that an exported symbol [global namespace] does not already exist
1607 * in the kernel or in some other module's exported symbol table.
1609 * You must hold the module_mutex.
1611 static int verify_export_symbols(struct module *mod)
1614 struct module *owner;
1615 const struct kernel_symbol *s;
1617 const struct kernel_symbol *sym;
1620 { mod->syms, mod->num_syms },
1621 { mod->gpl_syms, mod->num_gpl_syms },
1622 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1623 #ifdef CONFIG_UNUSED_SYMBOLS
1624 { mod->unused_syms, mod->num_unused_syms },
1625 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1629 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1630 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1631 if (find_symbol(s->name, &owner, NULL, true, false)) {
1633 "%s: exports duplicate symbol %s"
1635 mod->name, s->name, module_name(owner));
1643 /* Change all symbols so that st_value encodes the pointer directly. */
1644 static int simplify_symbols(Elf_Shdr *sechdrs,
1645 unsigned int symindex,
1647 unsigned int versindex,
1648 unsigned int pcpuindex,
1651 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1652 unsigned long secbase;
1653 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1655 const struct kernel_symbol *ksym;
1657 for (i = 1; i < n; i++) {
1658 switch (sym[i].st_shndx) {
1660 /* We compiled with -fno-common. These are not
1661 supposed to happen. */
1662 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1663 printk("%s: please compile with -fno-common\n",
1669 /* Don't need to do anything */
1670 DEBUGP("Absolute symbol: 0x%08lx\n",
1671 (long)sym[i].st_value);
1675 ksym = resolve_symbol_wait(sechdrs, versindex,
1676 strtab + sym[i].st_name,
1678 /* Ok if resolved. */
1679 if (ksym && !IS_ERR(ksym)) {
1680 sym[i].st_value = ksym->value;
1685 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1688 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
1689 mod->name, strtab + sym[i].st_name,
1691 ret = PTR_ERR(ksym) ?: -ENOENT;
1695 /* Divert to percpu allocation if a percpu var. */
1696 if (sym[i].st_shndx == pcpuindex)
1697 secbase = (unsigned long)mod_percpu(mod);
1699 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1700 sym[i].st_value += secbase;
1708 static int apply_relocations(struct module *mod,
1711 unsigned int symindex,
1712 unsigned int strindex)
1717 /* Now do relocations. */
1718 for (i = 1; i < hdr->e_shnum; i++) {
1719 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1720 unsigned int info = sechdrs[i].sh_info;
1722 /* Not a valid relocation section? */
1723 if (info >= hdr->e_shnum)
1726 /* Don't bother with non-allocated sections */
1727 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1730 if (sechdrs[i].sh_type == SHT_REL)
1731 err = apply_relocate(sechdrs, strtab, symindex, i, mod);
1732 else if (sechdrs[i].sh_type == SHT_RELA)
1733 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1741 /* Additional bytes needed by arch in front of individual sections */
1742 unsigned int __weak arch_mod_section_prepend(struct module *mod,
1743 unsigned int section)
1745 /* default implementation just returns zero */
1749 /* Update size with this section: return offset. */
1750 static long get_offset(struct module *mod, unsigned int *size,
1751 Elf_Shdr *sechdr, unsigned int section)
1755 *size += arch_mod_section_prepend(mod, section);
1756 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1757 *size = ret + sechdr->sh_size;
1761 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1762 might -- code, read-only data, read-write data, small data. Tally
1763 sizes, and place the offsets into sh_entsize fields: high bit means it
1765 static void layout_sections(struct module *mod,
1766 const Elf_Ehdr *hdr,
1768 const char *secstrings)
1770 static unsigned long const masks[][2] = {
1771 /* NOTE: all executable code must be the first section
1772 * in this array; otherwise modify the text_size
1773 * finder in the two loops below */
1774 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1775 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1776 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1777 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1781 for (i = 0; i < hdr->e_shnum; i++)
1782 sechdrs[i].sh_entsize = ~0UL;
1784 DEBUGP("Core section allocation order:\n");
1785 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1786 for (i = 0; i < hdr->e_shnum; ++i) {
1787 Elf_Shdr *s = &sechdrs[i];
1789 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1790 || (s->sh_flags & masks[m][1])
1791 || s->sh_entsize != ~0UL
1792 || strstarts(secstrings + s->sh_name, ".init"))
1794 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1795 DEBUGP("\t%s\n", secstrings + s->sh_name);
1798 mod->core_text_size = mod->core_size;
1801 DEBUGP("Init section allocation order:\n");
1802 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1803 for (i = 0; i < hdr->e_shnum; ++i) {
1804 Elf_Shdr *s = &sechdrs[i];
1806 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1807 || (s->sh_flags & masks[m][1])
1808 || s->sh_entsize != ~0UL
1809 || !strstarts(secstrings + s->sh_name, ".init"))
1811 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1812 | INIT_OFFSET_MASK);
1813 DEBUGP("\t%s\n", secstrings + s->sh_name);
1816 mod->init_text_size = mod->init_size;
1820 static void set_license(struct module *mod, const char *license)
1823 license = "unspecified";
1825 if (!license_is_gpl_compatible(license)) {
1826 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1827 printk(KERN_WARNING "%s: module license '%s' taints "
1828 "kernel.\n", mod->name, license);
1829 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1833 /* Parse tag=value strings from .modinfo section */
1834 static char *next_string(char *string, unsigned long *secsize)
1836 /* Skip non-zero chars */
1839 if ((*secsize)-- <= 1)
1843 /* Skip any zero padding. */
1844 while (!string[0]) {
1846 if ((*secsize)-- <= 1)
1852 static char *get_modinfo(const Elf_Shdr *sechdrs,
1857 unsigned int taglen = strlen(tag);
1858 unsigned long size = sechdrs[info].sh_size;
1860 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1861 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1862 return p + taglen + 1;
1867 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1868 unsigned int infoindex)
1870 struct module_attribute *attr;
1873 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1876 get_modinfo(sechdrs,
1882 static void free_modinfo(struct module *mod)
1884 struct module_attribute *attr;
1887 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1893 #ifdef CONFIG_KALLSYMS
1895 /* lookup symbol in given range of kernel_symbols */
1896 static const struct kernel_symbol *lookup_symbol(const char *name,
1897 const struct kernel_symbol *start,
1898 const struct kernel_symbol *stop)
1900 const struct kernel_symbol *ks = start;
1901 for (; ks < stop; ks++)
1902 if (strcmp(ks->name, name) == 0)
1907 static int is_exported(const char *name, unsigned long value,
1908 const struct module *mod)
1910 const struct kernel_symbol *ks;
1912 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1914 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1915 return ks != NULL && ks->value == value;
1919 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
1921 const Elf_Shdr *sechdrs = info->sechdrs;
1923 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1924 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1929 if (sym->st_shndx == SHN_UNDEF)
1931 if (sym->st_shndx == SHN_ABS)
1933 if (sym->st_shndx >= SHN_LORESERVE)
1935 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1937 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1938 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1939 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1941 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1946 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1947 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1952 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
1959 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1962 const Elf_Shdr *sec;
1964 if (src->st_shndx == SHN_UNDEF
1965 || src->st_shndx >= shnum
1969 sec = sechdrs + src->st_shndx;
1970 if (!(sec->sh_flags & SHF_ALLOC)
1971 #ifndef CONFIG_KALLSYMS_ALL
1972 || !(sec->sh_flags & SHF_EXECINSTR)
1974 || (sec->sh_entsize & INIT_OFFSET_MASK))
1980 static unsigned long layout_symtab(struct module *mod,
1982 unsigned int symindex,
1983 unsigned int strindex,
1984 const Elf_Ehdr *hdr,
1985 const char *secstrings,
1986 unsigned long *pstroffs,
1987 unsigned long *strmap)
1989 unsigned long symoffs;
1990 Elf_Shdr *symsect = sechdrs + symindex;
1991 Elf_Shdr *strsect = sechdrs + strindex;
1994 unsigned int i, nsrc, ndst;
1996 /* Put symbol section at end of init part of module. */
1997 symsect->sh_flags |= SHF_ALLOC;
1998 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1999 symindex) | INIT_OFFSET_MASK;
2000 DEBUGP("\t%s\n", secstrings + symsect->sh_name);
2002 src = (void *)hdr + symsect->sh_offset;
2003 nsrc = symsect->sh_size / sizeof(*src);
2004 strtab = (void *)hdr + strsect->sh_offset;
2005 for (ndst = i = 1; i < nsrc; ++i, ++src)
2006 if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
2007 unsigned int j = src->st_name;
2009 while(!__test_and_set_bit(j, strmap) && strtab[j])
2014 /* Append room for core symbols at end of core part. */
2015 symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
2016 mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
2018 /* Put string table section at end of init part of module. */
2019 strsect->sh_flags |= SHF_ALLOC;
2020 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
2021 strindex) | INIT_OFFSET_MASK;
2022 DEBUGP("\t%s\n", secstrings + strsect->sh_name);
2024 /* Append room for core symbols' strings at end of core part. */
2025 *pstroffs = mod->core_size;
2026 __set_bit(0, strmap);
2027 mod->core_size += bitmap_weight(strmap, strsect->sh_size);
2032 static void add_kallsyms(struct module *mod, struct load_info *info)
2034 unsigned int i, ndst;
2038 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2040 mod->symtab = (void *)symsec->sh_addr;
2041 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2042 /* Make sure we get permanent strtab: don't use info->strtab. */
2043 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2045 /* Set types up while we still have access to sections. */
2046 for (i = 0; i < mod->num_symtab; i++)
2047 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
2049 mod->core_symtab = dst = mod->module_core + info->symoffs;
2052 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
2053 if (!is_core_symbol(src, info->sechdrs, info->hdr->e_shnum))
2056 dst[ndst].st_name = bitmap_weight(info->strmap,
2060 mod->core_num_syms = ndst;
2062 mod->core_strtab = s = mod->module_core + info->stroffs;
2063 for (*s = 0, i = 1; i < info->sechdrs[info->index.str].sh_size; ++i)
2064 if (test_bit(i, info->strmap))
2065 *++s = mod->strtab[i];
2068 static inline unsigned long layout_symtab(struct module *mod,
2070 unsigned int symindex,
2071 unsigned int strindex,
2072 const Elf_Ehdr *hdr,
2073 const char *secstrings,
2074 unsigned long *pstroffs,
2075 unsigned long *strmap)
2080 static void add_kallsyms(struct module *mod, struct load_info *info)
2083 #endif /* CONFIG_KALLSYMS */
2085 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2087 #ifdef CONFIG_DYNAMIC_DEBUG
2088 if (ddebug_add_module(debug, num, debug->modname))
2089 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2094 static void dynamic_debug_remove(struct _ddebug *debug)
2097 ddebug_remove_module(debug->modname);
2100 static void *module_alloc_update_bounds(unsigned long size)
2102 void *ret = module_alloc(size);
2105 mutex_lock(&module_mutex);
2106 /* Update module bounds. */
2107 if ((unsigned long)ret < module_addr_min)
2108 module_addr_min = (unsigned long)ret;
2109 if ((unsigned long)ret + size > module_addr_max)
2110 module_addr_max = (unsigned long)ret + size;
2111 mutex_unlock(&module_mutex);
2116 #ifdef CONFIG_DEBUG_KMEMLEAK
2117 static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2118 const Elf_Shdr *sechdrs,
2119 const char *secstrings)
2123 /* only scan the sections containing data */
2124 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2126 for (i = 1; i < hdr->e_shnum; i++) {
2127 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2129 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
2130 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
2133 kmemleak_scan_area((void *)sechdrs[i].sh_addr,
2134 sechdrs[i].sh_size, GFP_KERNEL);
2138 static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2140 const char *secstrings)
2145 /* Sets info->hdr, info->len and info->args. */
2146 static int copy_and_check(struct load_info *info,
2147 const void __user *umod, unsigned long len,
2148 const char __user *uargs)
2153 if (len < sizeof(*hdr))
2156 /* Suck in entire file: we'll want most of it. */
2157 /* vmalloc barfs on "unusual" numbers. Check here */
2158 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
2161 if (copy_from_user(hdr, umod, len) != 0) {
2166 /* Sanity checks against insmoding binaries or wrong arch,
2167 weird elf version */
2168 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
2169 || hdr->e_type != ET_REL
2170 || !elf_check_arch(hdr)
2171 || hdr->e_shentsize != sizeof(Elf_Shdr)) {
2176 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
2181 /* Now copy in args */
2182 info->args = strndup_user(uargs, ~0UL >> 1);
2183 if (IS_ERR(info->args)) {
2184 err = PTR_ERR(info->args);
2197 static void free_copy(struct load_info *info)
2203 static int rewrite_section_headers(struct load_info *info)
2207 /* This should always be true, but let's be sure. */
2208 info->sechdrs[0].sh_addr = 0;
2210 for (i = 1; i < info->hdr->e_shnum; i++) {
2211 Elf_Shdr *shdr = &info->sechdrs[i];
2212 if (shdr->sh_type != SHT_NOBITS
2213 && info->len < shdr->sh_offset + shdr->sh_size) {
2214 printk(KERN_ERR "Module len %lu truncated\n",
2219 /* Mark all sections sh_addr with their address in the
2221 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2223 #ifndef CONFIG_MODULE_UNLOAD
2224 /* Don't load .exit sections */
2225 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2226 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2230 /* Track but don't keep modinfo and version sections. */
2231 info->index.vers = find_sec(info->hdr, info->sechdrs, info->secstrings, "__versions");
2232 info->index.info = find_sec(info->hdr, info->sechdrs, info->secstrings, ".modinfo");
2233 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2234 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2239 * Set up our basic convenience variables (pointers to section headers,
2240 * search for module section index etc), and do some basic section
2243 * Return the temporary module pointer (we'll replace it with the final
2244 * one when we move the module sections around).
2246 static struct module *setup_load_info(struct load_info *info)
2252 /* Set up the convenience variables */
2253 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2254 info->secstrings = (void *)info->hdr
2255 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2257 err = rewrite_section_headers(info);
2259 return ERR_PTR(err);
2261 /* Find internal symbols and strings. */
2262 for (i = 1; i < info->hdr->e_shnum; i++) {
2263 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2264 info->index.sym = i;
2265 info->index.str = info->sechdrs[i].sh_link;
2266 info->strtab = (char *)info->hdr
2267 + info->sechdrs[info->index.str].sh_offset;
2272 info->index.mod = find_sec(info->hdr, info->sechdrs, info->secstrings,
2273 ".gnu.linkonce.this_module");
2274 if (!info->index.mod) {
2275 printk(KERN_WARNING "No module found in object\n");
2276 return ERR_PTR(-ENOEXEC);
2278 /* This is temporary: point mod into copy of data. */
2279 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2281 if (info->index.sym == 0) {
2282 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2284 return ERR_PTR(-ENOEXEC);
2287 info->index.pcpu = find_pcpusec(info->hdr, info->sechdrs, info->secstrings);
2289 /* Check module struct version now, before we try to use module. */
2290 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2291 return ERR_PTR(-ENOEXEC);
2296 static int check_modinfo(struct module *mod,
2297 const Elf_Shdr *sechdrs,
2298 unsigned int infoindex, unsigned int versindex)
2300 const char *modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2303 /* This is allowed: modprobe --force will invalidate it. */
2305 err = try_to_force_load(mod, "bad vermagic");
2308 } else if (!same_magic(modmagic, vermagic, versindex)) {
2309 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2310 mod->name, modmagic, vermagic);
2314 if (get_modinfo(sechdrs, infoindex, "staging")) {
2315 add_taint_module(mod, TAINT_CRAP);
2316 printk(KERN_WARNING "%s: module is from the staging directory,"
2317 " the quality is unknown, you have been warned.\n",
2321 /* Set up license info based on the info section */
2322 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2327 static void find_module_sections(struct module *mod, Elf_Ehdr *hdr,
2328 Elf_Shdr *sechdrs, const char *secstrings)
2330 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2331 sizeof(*mod->kp), &mod->num_kp);
2332 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2333 sizeof(*mod->syms), &mod->num_syms);
2334 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2335 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2336 sizeof(*mod->gpl_syms),
2337 &mod->num_gpl_syms);
2338 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2339 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2340 "__ksymtab_gpl_future",
2341 sizeof(*mod->gpl_future_syms),
2342 &mod->num_gpl_future_syms);
2343 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2344 "__kcrctab_gpl_future");
2346 #ifdef CONFIG_UNUSED_SYMBOLS
2347 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2349 sizeof(*mod->unused_syms),
2350 &mod->num_unused_syms);
2351 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2352 "__kcrctab_unused");
2353 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2354 "__ksymtab_unused_gpl",
2355 sizeof(*mod->unused_gpl_syms),
2356 &mod->num_unused_gpl_syms);
2357 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2358 "__kcrctab_unused_gpl");
2360 #ifdef CONFIG_CONSTRUCTORS
2361 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2362 sizeof(*mod->ctors), &mod->num_ctors);
2365 #ifdef CONFIG_TRACEPOINTS
2366 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2368 sizeof(*mod->tracepoints),
2369 &mod->num_tracepoints);
2371 #ifdef CONFIG_EVENT_TRACING
2372 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2374 sizeof(*mod->trace_events),
2375 &mod->num_trace_events);
2377 * This section contains pointers to allocated objects in the trace
2378 * code and not scanning it leads to false positives.
2380 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2381 mod->num_trace_events, GFP_KERNEL);
2383 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2384 /* sechdrs[0].sh_size is always zero */
2385 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2387 sizeof(*mod->ftrace_callsites),
2388 &mod->num_ftrace_callsites);
2391 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2392 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2396 static int move_module(struct module *mod,
2397 Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
2398 const char *secstrings, unsigned modindex)
2403 /* Do the allocs. */
2404 ptr = module_alloc_update_bounds(mod->core_size);
2406 * The pointer to this block is stored in the module structure
2407 * which is inside the block. Just mark it as not being a
2410 kmemleak_not_leak(ptr);
2414 memset(ptr, 0, mod->core_size);
2415 mod->module_core = ptr;
2417 ptr = module_alloc_update_bounds(mod->init_size);
2419 * The pointer to this block is stored in the module structure
2420 * which is inside the block. This block doesn't need to be
2421 * scanned as it contains data and code that will be freed
2422 * after the module is initialized.
2424 kmemleak_ignore(ptr);
2425 if (!ptr && mod->init_size) {
2426 module_free(mod, mod->module_core);
2429 memset(ptr, 0, mod->init_size);
2430 mod->module_init = ptr;
2432 /* Transfer each section which specifies SHF_ALLOC */
2433 DEBUGP("final section addresses:\n");
2434 for (i = 0; i < hdr->e_shnum; i++) {
2437 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2440 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2441 dest = mod->module_init
2442 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2444 dest = mod->module_core + sechdrs[i].sh_entsize;
2446 if (sechdrs[i].sh_type != SHT_NOBITS)
2447 memcpy(dest, (void *)sechdrs[i].sh_addr,
2448 sechdrs[i].sh_size);
2449 /* Update sh_addr to point to copy in image. */
2450 sechdrs[i].sh_addr = (unsigned long)dest;
2451 DEBUGP("\t0x%lx %s\n",
2452 sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2458 static int check_module_license_and_versions(struct module *mod,
2462 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2463 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2464 * using GPL-only symbols it needs.
2466 if (strcmp(mod->name, "ndiswrapper") == 0)
2467 add_taint(TAINT_PROPRIETARY_MODULE);
2469 /* driverloader was caught wrongly pretending to be under GPL */
2470 if (strcmp(mod->name, "driverloader") == 0)
2471 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2473 #ifdef CONFIG_MODVERSIONS
2474 if ((mod->num_syms && !mod->crcs)
2475 || (mod->num_gpl_syms && !mod->gpl_crcs)
2476 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2477 #ifdef CONFIG_UNUSED_SYMBOLS
2478 || (mod->num_unused_syms && !mod->unused_crcs)
2479 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2482 return try_to_force_load(mod,
2483 "no versions for exported symbols");
2489 static void flush_module_icache(const struct module *mod)
2491 mm_segment_t old_fs;
2493 /* flush the icache in correct context */
2498 * Flush the instruction cache, since we've played with text.
2499 * Do it before processing of module parameters, so the module
2500 * can provide parameter accessor functions of its own.
2502 if (mod->module_init)
2503 flush_icache_range((unsigned long)mod->module_init,
2504 (unsigned long)mod->module_init
2506 flush_icache_range((unsigned long)mod->module_core,
2507 (unsigned long)mod->module_core + mod->core_size);
2512 static struct module *layout_and_allocate(struct load_info *info)
2514 /* Module within temporary copy. */
2518 mod = setup_load_info(info);
2522 err = check_modinfo(mod, info->sechdrs, info->index.info, info->index.vers);
2524 return ERR_PTR(err);
2526 /* Allow arches to frob section contents and sizes. */
2527 err = module_frob_arch_sections(info->hdr, info->sechdrs, info->secstrings, mod);
2531 if (info->index.pcpu) {
2532 /* We have a special allocation for this section. */
2533 err = percpu_modalloc(mod, info->sechdrs[info->index.pcpu].sh_size,
2534 info->sechdrs[info->index.pcpu].sh_addralign);
2537 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
2540 /* Determine total sizes, and put offsets in sh_entsize. For now
2541 this is done generically; there doesn't appear to be any
2542 special cases for the architectures. */
2543 layout_sections(mod, info->hdr, info->sechdrs, info->secstrings);
2545 info->strmap = kzalloc(BITS_TO_LONGS(info->sechdrs[info->index.str].sh_size)
2546 * sizeof(long), GFP_KERNEL);
2547 if (!info->strmap) {
2551 info->symoffs = layout_symtab(mod, info->sechdrs, info->index.sym, info->index.str, info->hdr,
2552 info->secstrings, &info->stroffs, info->strmap);
2554 /* Allocate and move to the final place */
2555 err = move_module(mod, info->hdr, info->sechdrs, info->secstrings, info->index.mod);
2559 /* Module has been copied to its final place now: return it. */
2560 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2561 kmemleak_load_module(mod, info->hdr, info->sechdrs, info->secstrings);
2565 kfree(info->strmap);
2567 percpu_modfree(mod);
2570 return ERR_PTR(err);
2573 /* mod is no longer valid after this! */
2574 static void module_deallocate(struct module *mod, struct load_info *info)
2576 kfree(info->strmap);
2577 percpu_modfree(mod);
2578 module_free(mod, mod->module_init);
2579 module_free(mod, mod->module_core);
2582 /* Allocate and load the module: note that size of section 0 is always
2583 zero, and we rely on this for optional sections. */
2584 static noinline struct module *load_module(void __user *umod,
2586 const char __user *uargs)
2588 struct load_info info = { NULL, };
2591 struct _ddebug *debug = NULL;
2592 unsigned int num_debug = 0;
2594 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2597 /* Copy in the blobs from userspace, check they are vaguely sane. */
2598 err = copy_and_check(&info, umod, len, uargs);
2600 return ERR_PTR(err);
2602 /* Figure out module layout, and allocate all the memory. */
2603 mod = layout_and_allocate(&info);
2609 /* Now we've moved module, initialize linked lists, etc. */
2610 err = module_unload_init(mod);
2614 /* Now we've got everything in the final locations, we can
2615 * find optional sections. */
2616 find_module_sections(mod, info.hdr, info.sechdrs, info.secstrings);
2618 err = check_module_license_and_versions(mod, info.sechdrs);
2622 /* Set up MODINFO_ATTR fields */
2623 setup_modinfo(mod, info.sechdrs, info.index.info);
2625 /* Fix up syms, so that st_value is a pointer to location. */
2626 err = simplify_symbols(info.sechdrs, info.index.sym, info.strtab, info.index.vers, info.index.pcpu,
2631 err = apply_relocations(mod, info.hdr, info.sechdrs, info.index.sym, info.index.str);
2635 /* Set up and sort exception table */
2636 mod->extable = section_objs(info.hdr, info.sechdrs, info.secstrings, "__ex_table",
2637 sizeof(*mod->extable), &mod->num_exentries);
2638 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2640 /* Finally, copy percpu area over. */
2641 percpu_modcopy(mod, (void *)info.sechdrs[info.index.pcpu].sh_addr,
2642 info.sechdrs[info.index.pcpu].sh_size);
2644 add_kallsyms(mod, &info);
2647 debug = section_objs(info.hdr, info.sechdrs, info.secstrings, "__verbose",
2648 sizeof(*debug), &num_debug);
2650 err = module_finalize(info.hdr, info.sechdrs, mod);
2654 flush_module_icache(mod);
2656 mod->args = info.args;
2658 mod->state = MODULE_STATE_COMING;
2660 /* Now sew it into the lists so we can get lockdep and oops
2661 * info during argument parsing. Noone should access us, since
2662 * strong_try_module_get() will fail.
2663 * lockdep/oops can run asynchronous, so use the RCU list insertion
2664 * function to insert in a way safe to concurrent readers.
2665 * The mutex protects against concurrent writers.
2667 mutex_lock(&module_mutex);
2668 if (find_module(mod->name)) {
2674 dynamic_debug_setup(debug, num_debug);
2676 /* Find duplicate symbols */
2677 err = verify_export_symbols(mod);
2681 list_add_rcu(&mod->list, &modules);
2682 mutex_unlock(&module_mutex);
2684 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2688 err = mod_sysfs_setup(mod, &info, mod->kp, mod->num_kp);
2692 /* Get rid of temporary copy and strmap. */
2696 trace_module_load(mod);
2702 mutex_lock(&module_mutex);
2703 /* Unlink carefully: kallsyms could be walking list. */
2704 list_del_rcu(&mod->list);
2706 dynamic_debug_remove(debug);
2708 mutex_unlock(&module_mutex);
2709 synchronize_sched();
2710 module_arch_cleanup(mod);
2714 module_unload_free(mod);
2716 module_deallocate(mod, &info);
2719 return ERR_PTR(err);
2722 /* Call module constructors. */
2723 static void do_mod_ctors(struct module *mod)
2725 #ifdef CONFIG_CONSTRUCTORS
2728 for (i = 0; i < mod->num_ctors; i++)
2733 /* This is where the real work happens */
2734 SYSCALL_DEFINE3(init_module, void __user *, umod,
2735 unsigned long, len, const char __user *, uargs)
2740 /* Must have permission */
2741 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2744 /* Do all the hard work */
2745 mod = load_module(umod, len, uargs);
2747 return PTR_ERR(mod);
2749 blocking_notifier_call_chain(&module_notify_list,
2750 MODULE_STATE_COMING, mod);
2753 /* Start the module */
2754 if (mod->init != NULL)
2755 ret = do_one_initcall(mod->init);
2757 /* Init routine failed: abort. Try to protect us from
2758 buggy refcounters. */
2759 mod->state = MODULE_STATE_GOING;
2760 synchronize_sched();
2762 blocking_notifier_call_chain(&module_notify_list,
2763 MODULE_STATE_GOING, mod);
2765 wake_up(&module_wq);
2770 "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2771 "%s: loading module anyway...\n",
2772 __func__, mod->name, ret,
2777 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2778 mod->state = MODULE_STATE_LIVE;
2779 wake_up(&module_wq);
2780 blocking_notifier_call_chain(&module_notify_list,
2781 MODULE_STATE_LIVE, mod);
2783 /* We need to finish all async code before the module init sequence is done */
2784 async_synchronize_full();
2786 mutex_lock(&module_mutex);
2787 /* Drop initial reference. */
2789 trim_init_extable(mod);
2790 #ifdef CONFIG_KALLSYMS
2791 mod->num_symtab = mod->core_num_syms;
2792 mod->symtab = mod->core_symtab;
2793 mod->strtab = mod->core_strtab;
2795 module_free(mod, mod->module_init);
2796 mod->module_init = NULL;
2798 mod->init_text_size = 0;
2799 mutex_unlock(&module_mutex);
2804 static inline int within(unsigned long addr, void *start, unsigned long size)
2806 return ((void *)addr >= start && (void *)addr < start + size);
2809 #ifdef CONFIG_KALLSYMS
2811 * This ignores the intensely annoying "mapping symbols" found
2812 * in ARM ELF files: $a, $t and $d.
2814 static inline int is_arm_mapping_symbol(const char *str)
2816 return str[0] == '$' && strchr("atd", str[1])
2817 && (str[2] == '\0' || str[2] == '.');
2820 static const char *get_ksymbol(struct module *mod,
2822 unsigned long *size,
2823 unsigned long *offset)
2825 unsigned int i, best = 0;
2826 unsigned long nextval;
2828 /* At worse, next value is at end of module */
2829 if (within_module_init(addr, mod))
2830 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2832 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2834 /* Scan for closest preceeding symbol, and next symbol. (ELF
2835 starts real symbols at 1). */
2836 for (i = 1; i < mod->num_symtab; i++) {
2837 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2840 /* We ignore unnamed symbols: they're uninformative
2841 * and inserted at a whim. */
2842 if (mod->symtab[i].st_value <= addr
2843 && mod->symtab[i].st_value > mod->symtab[best].st_value
2844 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2845 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2847 if (mod->symtab[i].st_value > addr
2848 && mod->symtab[i].st_value < nextval
2849 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2850 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2851 nextval = mod->symtab[i].st_value;
2858 *size = nextval - mod->symtab[best].st_value;
2860 *offset = addr - mod->symtab[best].st_value;
2861 return mod->strtab + mod->symtab[best].st_name;
2864 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2865 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2866 const char *module_address_lookup(unsigned long addr,
2867 unsigned long *size,
2868 unsigned long *offset,
2873 const char *ret = NULL;
2876 list_for_each_entry_rcu(mod, &modules, list) {
2877 if (within_module_init(addr, mod) ||
2878 within_module_core(addr, mod)) {
2880 *modname = mod->name;
2881 ret = get_ksymbol(mod, addr, size, offset);
2885 /* Make a copy in here where it's safe */
2887 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2894 int lookup_module_symbol_name(unsigned long addr, char *symname)
2899 list_for_each_entry_rcu(mod, &modules, list) {
2900 if (within_module_init(addr, mod) ||
2901 within_module_core(addr, mod)) {
2904 sym = get_ksymbol(mod, addr, NULL, NULL);
2907 strlcpy(symname, sym, KSYM_NAME_LEN);
2917 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2918 unsigned long *offset, char *modname, char *name)
2923 list_for_each_entry_rcu(mod, &modules, list) {
2924 if (within_module_init(addr, mod) ||
2925 within_module_core(addr, mod)) {
2928 sym = get_ksymbol(mod, addr, size, offset);
2932 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2934 strlcpy(name, sym, KSYM_NAME_LEN);
2944 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2945 char *name, char *module_name, int *exported)
2950 list_for_each_entry_rcu(mod, &modules, list) {
2951 if (symnum < mod->num_symtab) {
2952 *value = mod->symtab[symnum].st_value;
2953 *type = mod->symtab[symnum].st_info;
2954 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2956 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2957 *exported = is_exported(name, *value, mod);
2961 symnum -= mod->num_symtab;
2967 static unsigned long mod_find_symname(struct module *mod, const char *name)
2971 for (i = 0; i < mod->num_symtab; i++)
2972 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2973 mod->symtab[i].st_info != 'U')
2974 return mod->symtab[i].st_value;
2978 /* Look for this name: can be of form module:name. */
2979 unsigned long module_kallsyms_lookup_name(const char *name)
2983 unsigned long ret = 0;
2985 /* Don't lock: we're in enough trouble already. */
2987 if ((colon = strchr(name, ':')) != NULL) {
2989 if ((mod = find_module(name)) != NULL)
2990 ret = mod_find_symname(mod, colon+1);
2993 list_for_each_entry_rcu(mod, &modules, list)
2994 if ((ret = mod_find_symname(mod, name)) != 0)
3001 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3002 struct module *, unsigned long),
3009 list_for_each_entry(mod, &modules, list) {
3010 for (i = 0; i < mod->num_symtab; i++) {
3011 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
3012 mod, mod->symtab[i].st_value);
3019 #endif /* CONFIG_KALLSYMS */
3021 static char *module_flags(struct module *mod, char *buf)
3026 mod->state == MODULE_STATE_GOING ||
3027 mod->state == MODULE_STATE_COMING) {
3029 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
3031 if (mod->taints & (1 << TAINT_FORCED_MODULE))
3033 if (mod->taints & (1 << TAINT_CRAP))
3036 * TAINT_FORCED_RMMOD: could be added.
3037 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
3041 /* Show a - for module-is-being-unloaded */
3042 if (mod->state == MODULE_STATE_GOING)
3044 /* Show a + for module-is-being-loaded */
3045 if (mod->state == MODULE_STATE_COMING)
3054 #ifdef CONFIG_PROC_FS
3055 /* Called by the /proc file system to return a list of modules. */
3056 static void *m_start(struct seq_file *m, loff_t *pos)
3058 mutex_lock(&module_mutex);
3059 return seq_list_start(&modules, *pos);
3062 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3064 return seq_list_next(p, &modules, pos);
3067 static void m_stop(struct seq_file *m, void *p)
3069 mutex_unlock(&module_mutex);
3072 static int m_show(struct seq_file *m, void *p)
3074 struct module *mod = list_entry(p, struct module, list);
3077 seq_printf(m, "%s %u",
3078 mod->name, mod->init_size + mod->core_size);
3079 print_unload_info(m, mod);
3081 /* Informative for users. */
3082 seq_printf(m, " %s",
3083 mod->state == MODULE_STATE_GOING ? "Unloading":
3084 mod->state == MODULE_STATE_COMING ? "Loading":
3086 /* Used by oprofile and other similar tools. */
3087 seq_printf(m, " 0x%p", mod->module_core);
3091 seq_printf(m, " %s", module_flags(mod, buf));
3093 seq_printf(m, "\n");
3097 /* Format: modulename size refcount deps address
3099 Where refcount is a number or -, and deps is a comma-separated list
3102 static const struct seq_operations modules_op = {
3109 static int modules_open(struct inode *inode, struct file *file)
3111 return seq_open(file, &modules_op);
3114 static const struct file_operations proc_modules_operations = {
3115 .open = modules_open,
3117 .llseek = seq_lseek,
3118 .release = seq_release,
3121 static int __init proc_modules_init(void)
3123 proc_create("modules", 0, NULL, &proc_modules_operations);
3126 module_init(proc_modules_init);
3129 /* Given an address, look for it in the module exception tables. */
3130 const struct exception_table_entry *search_module_extables(unsigned long addr)
3132 const struct exception_table_entry *e = NULL;
3136 list_for_each_entry_rcu(mod, &modules, list) {
3137 if (mod->num_exentries == 0)
3140 e = search_extable(mod->extable,
3141 mod->extable + mod->num_exentries - 1,
3148 /* Now, if we found one, we are running inside it now, hence
3149 we cannot unload the module, hence no refcnt needed. */
3154 * is_module_address - is this address inside a module?
3155 * @addr: the address to check.
3157 * See is_module_text_address() if you simply want to see if the address
3158 * is code (not data).
3160 bool is_module_address(unsigned long addr)
3165 ret = __module_address(addr) != NULL;
3172 * __module_address - get the module which contains an address.
3173 * @addr: the address.
3175 * Must be called with preempt disabled or module mutex held so that
3176 * module doesn't get freed during this.
3178 struct module *__module_address(unsigned long addr)
3182 if (addr < module_addr_min || addr > module_addr_max)
3185 list_for_each_entry_rcu(mod, &modules, list)
3186 if (within_module_core(addr, mod)
3187 || within_module_init(addr, mod))
3191 EXPORT_SYMBOL_GPL(__module_address);
3194 * is_module_text_address - is this address inside module code?
3195 * @addr: the address to check.
3197 * See is_module_address() if you simply want to see if the address is
3198 * anywhere in a module. See kernel_text_address() for testing if an
3199 * address corresponds to kernel or module code.
3201 bool is_module_text_address(unsigned long addr)
3206 ret = __module_text_address(addr) != NULL;
3213 * __module_text_address - get the module whose code contains an address.
3214 * @addr: the address.
3216 * Must be called with preempt disabled or module mutex held so that
3217 * module doesn't get freed during this.
3219 struct module *__module_text_address(unsigned long addr)
3221 struct module *mod = __module_address(addr);
3223 /* Make sure it's within the text section. */
3224 if (!within(addr, mod->module_init, mod->init_text_size)
3225 && !within(addr, mod->module_core, mod->core_text_size))
3230 EXPORT_SYMBOL_GPL(__module_text_address);
3232 /* Don't grab lock, we're oopsing. */
3233 void print_modules(void)
3238 printk(KERN_DEFAULT "Modules linked in:");
3239 /* Most callers should already have preempt disabled, but make sure */
3241 list_for_each_entry_rcu(mod, &modules, list)
3242 printk(" %s%s", mod->name, module_flags(mod, buf));
3244 if (last_unloaded_module[0])
3245 printk(" [last unloaded: %s]", last_unloaded_module);
3249 #ifdef CONFIG_MODVERSIONS
3250 /* Generate the signature for all relevant module structures here.
3251 * If these change, we don't want to try to parse the module. */
3252 void module_layout(struct module *mod,
3253 struct modversion_info *ver,
3254 struct kernel_param *kp,
3255 struct kernel_symbol *ks,
3256 struct tracepoint *tp)
3259 EXPORT_SYMBOL(module_layout);
3262 #ifdef CONFIG_TRACEPOINTS
3263 void module_update_tracepoints(void)
3267 mutex_lock(&module_mutex);
3268 list_for_each_entry(mod, &modules, list)
3270 tracepoint_update_probe_range(mod->tracepoints,
3271 mod->tracepoints + mod->num_tracepoints);
3272 mutex_unlock(&module_mutex);
3276 * Returns 0 if current not found.
3277 * Returns 1 if current found.
3279 int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3281 struct module *iter_mod;
3284 mutex_lock(&module_mutex);
3285 list_for_each_entry(iter_mod, &modules, list) {
3286 if (!iter_mod->taints) {
3288 * Sorted module list
3290 if (iter_mod < iter->module)
3292 else if (iter_mod > iter->module)
3293 iter->tracepoint = NULL;
3294 found = tracepoint_get_iter_range(&iter->tracepoint,
3295 iter_mod->tracepoints,
3296 iter_mod->tracepoints
3297 + iter_mod->num_tracepoints);
3299 iter->module = iter_mod;
3304 mutex_unlock(&module_mutex);