2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 #include <linux/module.h>
20 #include <linux/moduleloader.h>
21 #include <linux/ftrace_event.h>
22 #include <linux/init.h>
23 #include <linux/kallsyms.h>
25 #include <linux/sysfs.h>
26 #include <linux/kernel.h>
27 #include <linux/slab.h>
28 #include <linux/vmalloc.h>
29 #include <linux/elf.h>
30 #include <linux/proc_fs.h>
31 #include <linux/seq_file.h>
32 #include <linux/syscalls.h>
33 #include <linux/fcntl.h>
34 #include <linux/rcupdate.h>
35 #include <linux/capability.h>
36 #include <linux/cpu.h>
37 #include <linux/moduleparam.h>
38 #include <linux/errno.h>
39 #include <linux/err.h>
40 #include <linux/vermagic.h>
41 #include <linux/notifier.h>
42 #include <linux/sched.h>
43 #include <linux/stop_machine.h>
44 #include <linux/device.h>
45 #include <linux/string.h>
46 #include <linux/mutex.h>
47 #include <linux/rculist.h>
48 #include <asm/uaccess.h>
49 #include <asm/cacheflush.h>
50 #include <asm/mmu_context.h>
51 #include <linux/license.h>
52 #include <asm/sections.h>
53 #include <linux/tracepoint.h>
54 #include <linux/ftrace.h>
55 #include <linux/async.h>
56 #include <linux/percpu.h>
57 #include <linux/kmemleak.h>
59 #define CREATE_TRACE_POINTS
60 #include <trace/events/module.h>
65 #define DEBUGP(fmt , a...)
68 #ifndef ARCH_SHF_SMALL
69 #define ARCH_SHF_SMALL 0
72 /* If this is set, the section belongs in the init part of the module */
73 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
77 * 1) List of modules (also safely readable with preempt_disable),
78 * 2) module_use links,
79 * 3) module_addr_min/module_addr_max.
80 * (delete uses stop_machine/add uses RCU list operations). */
81 DEFINE_MUTEX(module_mutex);
82 EXPORT_SYMBOL_GPL(module_mutex);
83 static LIST_HEAD(modules);
84 #ifdef CONFIG_KGDB_KDB
85 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
86 #endif /* CONFIG_KGDB_KDB */
89 /* Block module loading/unloading? */
90 int modules_disabled = 0;
92 /* Waiting for a module to finish initializing? */
93 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
95 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
97 /* Bounds of module allocation, for speeding __module_address.
98 * Protected by module_mutex. */
99 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
101 int register_module_notifier(struct notifier_block * nb)
103 return blocking_notifier_chain_register(&module_notify_list, nb);
105 EXPORT_SYMBOL(register_module_notifier);
107 int unregister_module_notifier(struct notifier_block * nb)
109 return blocking_notifier_chain_unregister(&module_notify_list, nb);
111 EXPORT_SYMBOL(unregister_module_notifier);
113 /* We require a truly strong try_module_get(): 0 means failure due to
114 ongoing or failed initialization etc. */
115 static inline int strong_try_module_get(struct module *mod)
117 if (mod && mod->state == MODULE_STATE_COMING)
119 if (try_module_get(mod))
125 static inline void add_taint_module(struct module *mod, unsigned flag)
128 mod->taints |= (1U << flag);
132 * A thread that wants to hold a reference to a module only while it
133 * is running can call this to safely exit. nfsd and lockd use this.
135 void __module_put_and_exit(struct module *mod, long code)
140 EXPORT_SYMBOL(__module_put_and_exit);
142 /* Find a module section: 0 means not found. */
143 static unsigned int find_sec(Elf_Ehdr *hdr,
145 const char *secstrings,
150 for (i = 1; i < hdr->e_shnum; i++)
151 /* Alloc bit cleared means "ignore it." */
152 if ((sechdrs[i].sh_flags & SHF_ALLOC)
153 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
158 /* Find a module section, or NULL. */
159 static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
160 const char *secstrings, const char *name)
162 /* Section 0 has sh_addr 0. */
163 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
166 /* Find a module section, or NULL. Fill in number of "objects" in section. */
167 static void *section_objs(Elf_Ehdr *hdr,
169 const char *secstrings,
174 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
176 /* Section 0 has sh_addr 0 and sh_size 0. */
177 *num = sechdrs[sec].sh_size / object_size;
178 return (void *)sechdrs[sec].sh_addr;
181 /* Provided by the linker */
182 extern const struct kernel_symbol __start___ksymtab[];
183 extern const struct kernel_symbol __stop___ksymtab[];
184 extern const struct kernel_symbol __start___ksymtab_gpl[];
185 extern const struct kernel_symbol __stop___ksymtab_gpl[];
186 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
187 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
188 extern const unsigned long __start___kcrctab[];
189 extern const unsigned long __start___kcrctab_gpl[];
190 extern const unsigned long __start___kcrctab_gpl_future[];
191 #ifdef CONFIG_UNUSED_SYMBOLS
192 extern const struct kernel_symbol __start___ksymtab_unused[];
193 extern const struct kernel_symbol __stop___ksymtab_unused[];
194 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
195 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
196 extern const unsigned long __start___kcrctab_unused[];
197 extern const unsigned long __start___kcrctab_unused_gpl[];
200 #ifndef CONFIG_MODVERSIONS
201 #define symversion(base, idx) NULL
203 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
206 static bool each_symbol_in_section(const struct symsearch *arr,
207 unsigned int arrsize,
208 struct module *owner,
209 bool (*fn)(const struct symsearch *syms,
210 struct module *owner,
211 unsigned int symnum, void *data),
216 for (j = 0; j < arrsize; j++) {
217 for (i = 0; i < arr[j].stop - arr[j].start; i++)
218 if (fn(&arr[j], owner, i, data))
225 /* Returns true as soon as fn returns true, otherwise false. */
226 bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
227 unsigned int symnum, void *data), void *data)
230 const struct symsearch arr[] = {
231 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
232 NOT_GPL_ONLY, false },
233 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
234 __start___kcrctab_gpl,
236 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
237 __start___kcrctab_gpl_future,
238 WILL_BE_GPL_ONLY, false },
239 #ifdef CONFIG_UNUSED_SYMBOLS
240 { __start___ksymtab_unused, __stop___ksymtab_unused,
241 __start___kcrctab_unused,
242 NOT_GPL_ONLY, true },
243 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
244 __start___kcrctab_unused_gpl,
249 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
252 list_for_each_entry_rcu(mod, &modules, list) {
253 struct symsearch arr[] = {
254 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
255 NOT_GPL_ONLY, false },
256 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
259 { mod->gpl_future_syms,
260 mod->gpl_future_syms + mod->num_gpl_future_syms,
261 mod->gpl_future_crcs,
262 WILL_BE_GPL_ONLY, false },
263 #ifdef CONFIG_UNUSED_SYMBOLS
265 mod->unused_syms + mod->num_unused_syms,
267 NOT_GPL_ONLY, true },
268 { mod->unused_gpl_syms,
269 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
270 mod->unused_gpl_crcs,
275 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
280 EXPORT_SYMBOL_GPL(each_symbol);
282 struct find_symbol_arg {
289 struct module *owner;
290 const unsigned long *crc;
291 const struct kernel_symbol *sym;
294 static bool find_symbol_in_section(const struct symsearch *syms,
295 struct module *owner,
296 unsigned int symnum, void *data)
298 struct find_symbol_arg *fsa = data;
300 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
304 if (syms->licence == GPL_ONLY)
306 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
307 printk(KERN_WARNING "Symbol %s is being used "
308 "by a non-GPL module, which will not "
309 "be allowed in the future\n", fsa->name);
310 printk(KERN_WARNING "Please see the file "
311 "Documentation/feature-removal-schedule.txt "
312 "in the kernel source tree for more details.\n");
316 #ifdef CONFIG_UNUSED_SYMBOLS
317 if (syms->unused && fsa->warn) {
318 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
319 "however this module is using it.\n", fsa->name);
321 "This symbol will go away in the future.\n");
323 "Please evalute if this is the right api to use and if "
324 "it really is, submit a report the linux kernel "
325 "mailinglist together with submitting your code for "
331 fsa->crc = symversion(syms->crcs, symnum);
332 fsa->sym = &syms->start[symnum];
336 /* Find a symbol and return it, along with, (optional) crc and
337 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
338 const struct kernel_symbol *find_symbol(const char *name,
339 struct module **owner,
340 const unsigned long **crc,
344 struct find_symbol_arg fsa;
350 if (each_symbol(find_symbol_in_section, &fsa)) {
358 DEBUGP("Failed to find symbol %s\n", name);
361 EXPORT_SYMBOL_GPL(find_symbol);
363 /* Search for module by name: must hold module_mutex. */
364 struct module *find_module(const char *name)
368 list_for_each_entry(mod, &modules, list) {
369 if (strcmp(mod->name, name) == 0)
374 EXPORT_SYMBOL_GPL(find_module);
378 static inline void __percpu *mod_percpu(struct module *mod)
383 static int percpu_modalloc(struct module *mod,
384 unsigned long size, unsigned long align)
386 if (align > PAGE_SIZE) {
387 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
388 mod->name, align, PAGE_SIZE);
392 mod->percpu = __alloc_reserved_percpu(size, align);
395 "Could not allocate %lu bytes percpu data\n", size);
398 mod->percpu_size = size;
402 static void percpu_modfree(struct module *mod)
404 free_percpu(mod->percpu);
407 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
409 const char *secstrings)
411 return find_sec(hdr, sechdrs, secstrings, ".data..percpu");
414 static void percpu_modcopy(struct module *mod,
415 const void *from, unsigned long size)
419 for_each_possible_cpu(cpu)
420 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
424 * is_module_percpu_address - test whether address is from module static percpu
425 * @addr: address to test
427 * Test whether @addr belongs to module static percpu area.
430 * %true if @addr is from module static percpu area
432 bool is_module_percpu_address(unsigned long addr)
439 list_for_each_entry_rcu(mod, &modules, list) {
440 if (!mod->percpu_size)
442 for_each_possible_cpu(cpu) {
443 void *start = per_cpu_ptr(mod->percpu, cpu);
445 if ((void *)addr >= start &&
446 (void *)addr < start + mod->percpu_size) {
457 #else /* ... !CONFIG_SMP */
459 static inline void __percpu *mod_percpu(struct module *mod)
463 static inline int percpu_modalloc(struct module *mod,
464 unsigned long size, unsigned long align)
468 static inline void percpu_modfree(struct module *mod)
471 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
473 const char *secstrings)
477 static inline void percpu_modcopy(struct module *mod,
478 const void *from, unsigned long size)
480 /* pcpusec should be 0, and size of that section should be 0. */
483 bool is_module_percpu_address(unsigned long addr)
488 #endif /* CONFIG_SMP */
490 #define MODINFO_ATTR(field) \
491 static void setup_modinfo_##field(struct module *mod, const char *s) \
493 mod->field = kstrdup(s, GFP_KERNEL); \
495 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
496 struct module *mod, char *buffer) \
498 return sprintf(buffer, "%s\n", mod->field); \
500 static int modinfo_##field##_exists(struct module *mod) \
502 return mod->field != NULL; \
504 static void free_modinfo_##field(struct module *mod) \
509 static struct module_attribute modinfo_##field = { \
510 .attr = { .name = __stringify(field), .mode = 0444 }, \
511 .show = show_modinfo_##field, \
512 .setup = setup_modinfo_##field, \
513 .test = modinfo_##field##_exists, \
514 .free = free_modinfo_##field, \
517 MODINFO_ATTR(version);
518 MODINFO_ATTR(srcversion);
520 static char last_unloaded_module[MODULE_NAME_LEN+1];
522 #ifdef CONFIG_MODULE_UNLOAD
524 EXPORT_TRACEPOINT_SYMBOL(module_get);
526 /* Init the unload section of the module. */
527 static int module_unload_init(struct module *mod)
529 mod->refptr = alloc_percpu(struct module_ref);
533 INIT_LIST_HEAD(&mod->source_list);
534 INIT_LIST_HEAD(&mod->target_list);
536 /* Hold reference count during initialization. */
537 __this_cpu_write(mod->refptr->incs, 1);
538 /* Backwards compatibility macros put refcount during init. */
539 mod->waiter = current;
544 /* Does a already use b? */
545 static int already_uses(struct module *a, struct module *b)
547 struct module_use *use;
549 list_for_each_entry(use, &b->source_list, source_list) {
550 if (use->source == a) {
551 DEBUGP("%s uses %s!\n", a->name, b->name);
555 DEBUGP("%s does not use %s!\n", a->name, b->name);
561 * - we add 'a' as a "source", 'b' as a "target" of module use
562 * - the module_use is added to the list of 'b' sources (so
563 * 'b' can walk the list to see who sourced them), and of 'a'
564 * targets (so 'a' can see what modules it targets).
566 static int add_module_usage(struct module *a, struct module *b)
568 struct module_use *use;
570 DEBUGP("Allocating new usage for %s.\n", a->name);
571 use = kmalloc(sizeof(*use), GFP_ATOMIC);
573 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
579 list_add(&use->source_list, &b->source_list);
580 list_add(&use->target_list, &a->target_list);
584 /* Module a uses b: caller needs module_mutex() */
585 int ref_module(struct module *a, struct module *b)
589 if (b == NULL || already_uses(a, b))
592 /* If module isn't available, we fail. */
593 err = strong_try_module_get(b);
597 err = add_module_usage(a, b);
604 EXPORT_SYMBOL_GPL(ref_module);
606 /* Clear the unload stuff of the module. */
607 static void module_unload_free(struct module *mod)
609 struct module_use *use, *tmp;
611 mutex_lock(&module_mutex);
612 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
613 struct module *i = use->target;
614 DEBUGP("%s unusing %s\n", mod->name, i->name);
616 list_del(&use->source_list);
617 list_del(&use->target_list);
620 mutex_unlock(&module_mutex);
622 free_percpu(mod->refptr);
625 #ifdef CONFIG_MODULE_FORCE_UNLOAD
626 static inline int try_force_unload(unsigned int flags)
628 int ret = (flags & O_TRUNC);
630 add_taint(TAINT_FORCED_RMMOD);
634 static inline int try_force_unload(unsigned int flags)
638 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
647 /* Whole machine is stopped with interrupts off when this runs. */
648 static int __try_stop_module(void *_sref)
650 struct stopref *sref = _sref;
652 /* If it's not unused, quit unless we're forcing. */
653 if (module_refcount(sref->mod) != 0) {
654 if (!(*sref->forced = try_force_unload(sref->flags)))
658 /* Mark it as dying. */
659 sref->mod->state = MODULE_STATE_GOING;
663 static int try_stop_module(struct module *mod, int flags, int *forced)
665 if (flags & O_NONBLOCK) {
666 struct stopref sref = { mod, flags, forced };
668 return stop_machine(__try_stop_module, &sref, NULL);
670 /* We don't need to stop the machine for this. */
671 mod->state = MODULE_STATE_GOING;
677 unsigned int module_refcount(struct module *mod)
679 unsigned int incs = 0, decs = 0;
682 for_each_possible_cpu(cpu)
683 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
685 * ensure the incs are added up after the decs.
686 * module_put ensures incs are visible before decs with smp_wmb.
688 * This 2-count scheme avoids the situation where the refcount
689 * for CPU0 is read, then CPU0 increments the module refcount,
690 * then CPU1 drops that refcount, then the refcount for CPU1 is
691 * read. We would record a decrement but not its corresponding
692 * increment so we would see a low count (disaster).
694 * Rare situation? But module_refcount can be preempted, and we
695 * might be tallying up 4096+ CPUs. So it is not impossible.
698 for_each_possible_cpu(cpu)
699 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
702 EXPORT_SYMBOL(module_refcount);
704 /* This exists whether we can unload or not */
705 static void free_module(struct module *mod);
707 static void wait_for_zero_refcount(struct module *mod)
709 /* Since we might sleep for some time, release the mutex first */
710 mutex_unlock(&module_mutex);
712 DEBUGP("Looking at refcount...\n");
713 set_current_state(TASK_UNINTERRUPTIBLE);
714 if (module_refcount(mod) == 0)
718 current->state = TASK_RUNNING;
719 mutex_lock(&module_mutex);
722 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
726 char name[MODULE_NAME_LEN];
729 if (!capable(CAP_SYS_MODULE) || modules_disabled)
732 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
734 name[MODULE_NAME_LEN-1] = '\0';
736 if (mutex_lock_interruptible(&module_mutex) != 0)
739 mod = find_module(name);
745 if (!list_empty(&mod->source_list)) {
746 /* Other modules depend on us: get rid of them first. */
751 /* Doing init or already dying? */
752 if (mod->state != MODULE_STATE_LIVE) {
753 /* FIXME: if (force), slam module count and wake up
755 DEBUGP("%s already dying\n", mod->name);
760 /* If it has an init func, it must have an exit func to unload */
761 if (mod->init && !mod->exit) {
762 forced = try_force_unload(flags);
764 /* This module can't be removed */
770 /* Set this up before setting mod->state */
771 mod->waiter = current;
773 /* Stop the machine so refcounts can't move and disable module. */
774 ret = try_stop_module(mod, flags, &forced);
778 /* Never wait if forced. */
779 if (!forced && module_refcount(mod) != 0)
780 wait_for_zero_refcount(mod);
782 mutex_unlock(&module_mutex);
783 /* Final destruction now noone is using it. */
784 if (mod->exit != NULL)
786 blocking_notifier_call_chain(&module_notify_list,
787 MODULE_STATE_GOING, mod);
788 async_synchronize_full();
790 /* Store the name of the last unloaded module for diagnostic purposes */
791 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
796 mutex_unlock(&module_mutex);
800 static inline void print_unload_info(struct seq_file *m, struct module *mod)
802 struct module_use *use;
803 int printed_something = 0;
805 seq_printf(m, " %u ", module_refcount(mod));
807 /* Always include a trailing , so userspace can differentiate
808 between this and the old multi-field proc format. */
809 list_for_each_entry(use, &mod->source_list, source_list) {
810 printed_something = 1;
811 seq_printf(m, "%s,", use->source->name);
814 if (mod->init != NULL && mod->exit == NULL) {
815 printed_something = 1;
816 seq_printf(m, "[permanent],");
819 if (!printed_something)
823 void __symbol_put(const char *symbol)
825 struct module *owner;
828 if (!find_symbol(symbol, &owner, NULL, true, false))
833 EXPORT_SYMBOL(__symbol_put);
835 /* Note this assumes addr is a function, which it currently always is. */
836 void symbol_put_addr(void *addr)
838 struct module *modaddr;
839 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
841 if (core_kernel_text(a))
844 /* module_text_address is safe here: we're supposed to have reference
845 * to module from symbol_get, so it can't go away. */
846 modaddr = __module_text_address(a);
850 EXPORT_SYMBOL_GPL(symbol_put_addr);
852 static ssize_t show_refcnt(struct module_attribute *mattr,
853 struct module *mod, char *buffer)
855 return sprintf(buffer, "%u\n", module_refcount(mod));
858 static struct module_attribute refcnt = {
859 .attr = { .name = "refcnt", .mode = 0444 },
863 void module_put(struct module *module)
867 smp_wmb(); /* see comment in module_refcount */
868 __this_cpu_inc(module->refptr->decs);
870 trace_module_put(module, _RET_IP_);
871 /* Maybe they're waiting for us to drop reference? */
872 if (unlikely(!module_is_live(module)))
873 wake_up_process(module->waiter);
877 EXPORT_SYMBOL(module_put);
879 #else /* !CONFIG_MODULE_UNLOAD */
880 static inline void print_unload_info(struct seq_file *m, struct module *mod)
882 /* We don't know the usage count, or what modules are using. */
883 seq_printf(m, " - -");
886 static inline void module_unload_free(struct module *mod)
890 int ref_module(struct module *a, struct module *b)
892 return strong_try_module_get(b);
894 EXPORT_SYMBOL_GPL(ref_module);
896 static inline int module_unload_init(struct module *mod)
900 #endif /* CONFIG_MODULE_UNLOAD */
902 static ssize_t show_initstate(struct module_attribute *mattr,
903 struct module *mod, char *buffer)
905 const char *state = "unknown";
907 switch (mod->state) {
908 case MODULE_STATE_LIVE:
911 case MODULE_STATE_COMING:
914 case MODULE_STATE_GOING:
918 return sprintf(buffer, "%s\n", state);
921 static struct module_attribute initstate = {
922 .attr = { .name = "initstate", .mode = 0444 },
923 .show = show_initstate,
926 static struct module_attribute *modinfo_attrs[] = {
930 #ifdef CONFIG_MODULE_UNLOAD
936 static const char vermagic[] = VERMAGIC_STRING;
938 static int try_to_force_load(struct module *mod, const char *reason)
940 #ifdef CONFIG_MODULE_FORCE_LOAD
941 if (!test_taint(TAINT_FORCED_MODULE))
942 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
944 add_taint_module(mod, TAINT_FORCED_MODULE);
951 #ifdef CONFIG_MODVERSIONS
952 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
953 static unsigned long maybe_relocated(unsigned long crc,
954 const struct module *crc_owner)
956 #ifdef ARCH_RELOCATES_KCRCTAB
957 if (crc_owner == NULL)
958 return crc - (unsigned long)reloc_start;
963 static int check_version(Elf_Shdr *sechdrs,
964 unsigned int versindex,
967 const unsigned long *crc,
968 const struct module *crc_owner)
970 unsigned int i, num_versions;
971 struct modversion_info *versions;
973 /* Exporting module didn't supply crcs? OK, we're already tainted. */
977 /* No versions at all? modprobe --force does this. */
979 return try_to_force_load(mod, symname) == 0;
981 versions = (void *) sechdrs[versindex].sh_addr;
982 num_versions = sechdrs[versindex].sh_size
983 / sizeof(struct modversion_info);
985 for (i = 0; i < num_versions; i++) {
986 if (strcmp(versions[i].name, symname) != 0)
989 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
991 DEBUGP("Found checksum %lX vs module %lX\n",
992 maybe_relocated(*crc, crc_owner), versions[i].crc);
996 printk(KERN_WARNING "%s: no symbol version for %s\n",
1001 printk("%s: disagrees about version of symbol %s\n",
1002 mod->name, symname);
1006 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1007 unsigned int versindex,
1010 const unsigned long *crc;
1012 /* Since this should be found in kernel (which can't be removed),
1013 * no locking is necessary. */
1014 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1017 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1021 /* First part is kernel version, which we ignore if module has crcs. */
1022 static inline int same_magic(const char *amagic, const char *bmagic,
1026 amagic += strcspn(amagic, " ");
1027 bmagic += strcspn(bmagic, " ");
1029 return strcmp(amagic, bmagic) == 0;
1032 static inline int check_version(Elf_Shdr *sechdrs,
1033 unsigned int versindex,
1034 const char *symname,
1036 const unsigned long *crc,
1037 const struct module *crc_owner)
1042 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1043 unsigned int versindex,
1049 static inline int same_magic(const char *amagic, const char *bmagic,
1052 return strcmp(amagic, bmagic) == 0;
1054 #endif /* CONFIG_MODVERSIONS */
1056 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1057 static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
1058 unsigned int versindex,
1063 struct module *owner;
1064 const struct kernel_symbol *sym;
1065 const unsigned long *crc;
1068 mutex_lock(&module_mutex);
1069 sym = find_symbol(name, &owner, &crc,
1070 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1074 if (!check_version(sechdrs, versindex, name, mod, crc, owner)) {
1075 sym = ERR_PTR(-EINVAL);
1079 err = ref_module(mod, owner);
1086 /* We must make copy under the lock if we failed to get ref. */
1087 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1089 mutex_unlock(&module_mutex);
1093 static const struct kernel_symbol *resolve_symbol_wait(Elf_Shdr *sechdrs,
1094 unsigned int versindex,
1098 const struct kernel_symbol *ksym;
1099 char ownername[MODULE_NAME_LEN];
1101 if (wait_event_interruptible_timeout(module_wq,
1102 !IS_ERR(ksym = resolve_symbol(sechdrs, versindex, name,
1104 PTR_ERR(ksym) != -EBUSY,
1106 printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
1107 mod->name, ownername);
1113 * /sys/module/foo/sections stuff
1114 * J. Corbet <corbet@lwn.net>
1116 #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1118 static inline bool sect_empty(const Elf_Shdr *sect)
1120 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1123 struct module_sect_attr
1125 struct module_attribute mattr;
1127 unsigned long address;
1130 struct module_sect_attrs
1132 struct attribute_group grp;
1133 unsigned int nsections;
1134 struct module_sect_attr attrs[0];
1137 static ssize_t module_sect_show(struct module_attribute *mattr,
1138 struct module *mod, char *buf)
1140 struct module_sect_attr *sattr =
1141 container_of(mattr, struct module_sect_attr, mattr);
1142 return sprintf(buf, "0x%lx\n", sattr->address);
1145 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1147 unsigned int section;
1149 for (section = 0; section < sect_attrs->nsections; section++)
1150 kfree(sect_attrs->attrs[section].name);
1154 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1155 char *secstrings, Elf_Shdr *sechdrs)
1157 unsigned int nloaded = 0, i, size[2];
1158 struct module_sect_attrs *sect_attrs;
1159 struct module_sect_attr *sattr;
1160 struct attribute **gattr;
1162 /* Count loaded sections and allocate structures */
1163 for (i = 0; i < nsect; i++)
1164 if (!sect_empty(&sechdrs[i]))
1166 size[0] = ALIGN(sizeof(*sect_attrs)
1167 + nloaded * sizeof(sect_attrs->attrs[0]),
1168 sizeof(sect_attrs->grp.attrs[0]));
1169 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1170 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1171 if (sect_attrs == NULL)
1174 /* Setup section attributes. */
1175 sect_attrs->grp.name = "sections";
1176 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1178 sect_attrs->nsections = 0;
1179 sattr = §_attrs->attrs[0];
1180 gattr = §_attrs->grp.attrs[0];
1181 for (i = 0; i < nsect; i++) {
1182 if (sect_empty(&sechdrs[i]))
1184 sattr->address = sechdrs[i].sh_addr;
1185 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1187 if (sattr->name == NULL)
1189 sect_attrs->nsections++;
1190 sysfs_attr_init(&sattr->mattr.attr);
1191 sattr->mattr.show = module_sect_show;
1192 sattr->mattr.store = NULL;
1193 sattr->mattr.attr.name = sattr->name;
1194 sattr->mattr.attr.mode = S_IRUGO;
1195 *(gattr++) = &(sattr++)->mattr.attr;
1199 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1202 mod->sect_attrs = sect_attrs;
1205 free_sect_attrs(sect_attrs);
1208 static void remove_sect_attrs(struct module *mod)
1210 if (mod->sect_attrs) {
1211 sysfs_remove_group(&mod->mkobj.kobj,
1212 &mod->sect_attrs->grp);
1213 /* We are positive that no one is using any sect attrs
1214 * at this point. Deallocate immediately. */
1215 free_sect_attrs(mod->sect_attrs);
1216 mod->sect_attrs = NULL;
1221 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1224 struct module_notes_attrs {
1225 struct kobject *dir;
1227 struct bin_attribute attrs[0];
1230 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1231 struct bin_attribute *bin_attr,
1232 char *buf, loff_t pos, size_t count)
1235 * The caller checked the pos and count against our size.
1237 memcpy(buf, bin_attr->private + pos, count);
1241 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1244 if (notes_attrs->dir) {
1246 sysfs_remove_bin_file(notes_attrs->dir,
1247 ¬es_attrs->attrs[i]);
1248 kobject_put(notes_attrs->dir);
1253 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1254 char *secstrings, Elf_Shdr *sechdrs)
1256 unsigned int notes, loaded, i;
1257 struct module_notes_attrs *notes_attrs;
1258 struct bin_attribute *nattr;
1260 /* failed to create section attributes, so can't create notes */
1261 if (!mod->sect_attrs)
1264 /* Count notes sections and allocate structures. */
1266 for (i = 0; i < nsect; i++)
1267 if (!sect_empty(&sechdrs[i]) &&
1268 (sechdrs[i].sh_type == SHT_NOTE))
1274 notes_attrs = kzalloc(sizeof(*notes_attrs)
1275 + notes * sizeof(notes_attrs->attrs[0]),
1277 if (notes_attrs == NULL)
1280 notes_attrs->notes = notes;
1281 nattr = ¬es_attrs->attrs[0];
1282 for (loaded = i = 0; i < nsect; ++i) {
1283 if (sect_empty(&sechdrs[i]))
1285 if (sechdrs[i].sh_type == SHT_NOTE) {
1286 sysfs_bin_attr_init(nattr);
1287 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1288 nattr->attr.mode = S_IRUGO;
1289 nattr->size = sechdrs[i].sh_size;
1290 nattr->private = (void *) sechdrs[i].sh_addr;
1291 nattr->read = module_notes_read;
1297 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1298 if (!notes_attrs->dir)
1301 for (i = 0; i < notes; ++i)
1302 if (sysfs_create_bin_file(notes_attrs->dir,
1303 ¬es_attrs->attrs[i]))
1306 mod->notes_attrs = notes_attrs;
1310 free_notes_attrs(notes_attrs, i);
1313 static void remove_notes_attrs(struct module *mod)
1315 if (mod->notes_attrs)
1316 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1321 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1322 char *sectstrings, Elf_Shdr *sechdrs)
1326 static inline void remove_sect_attrs(struct module *mod)
1330 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1331 char *sectstrings, Elf_Shdr *sechdrs)
1335 static inline void remove_notes_attrs(struct module *mod)
1341 static void add_usage_links(struct module *mod)
1343 #ifdef CONFIG_MODULE_UNLOAD
1344 struct module_use *use;
1347 mutex_lock(&module_mutex);
1348 list_for_each_entry(use, &mod->target_list, target_list) {
1349 nowarn = sysfs_create_link(use->target->holders_dir,
1350 &mod->mkobj.kobj, mod->name);
1352 mutex_unlock(&module_mutex);
1356 static void del_usage_links(struct module *mod)
1358 #ifdef CONFIG_MODULE_UNLOAD
1359 struct module_use *use;
1361 mutex_lock(&module_mutex);
1362 list_for_each_entry(use, &mod->target_list, target_list)
1363 sysfs_remove_link(use->target->holders_dir, mod->name);
1364 mutex_unlock(&module_mutex);
1368 static int module_add_modinfo_attrs(struct module *mod)
1370 struct module_attribute *attr;
1371 struct module_attribute *temp_attr;
1375 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1376 (ARRAY_SIZE(modinfo_attrs) + 1)),
1378 if (!mod->modinfo_attrs)
1381 temp_attr = mod->modinfo_attrs;
1382 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1384 (attr->test && attr->test(mod))) {
1385 memcpy(temp_attr, attr, sizeof(*temp_attr));
1386 sysfs_attr_init(&temp_attr->attr);
1387 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1394 static void module_remove_modinfo_attrs(struct module *mod)
1396 struct module_attribute *attr;
1399 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1400 /* pick a field to test for end of list */
1401 if (!attr->attr.name)
1403 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1407 kfree(mod->modinfo_attrs);
1410 static int mod_sysfs_init(struct module *mod)
1413 struct kobject *kobj;
1415 if (!module_sysfs_initialized) {
1416 printk(KERN_ERR "%s: module sysfs not initialized\n",
1422 kobj = kset_find_obj(module_kset, mod->name);
1424 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1430 mod->mkobj.mod = mod;
1432 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1433 mod->mkobj.kobj.kset = module_kset;
1434 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1437 kobject_put(&mod->mkobj.kobj);
1439 /* delay uevent until full sysfs population */
1444 static int mod_sysfs_setup(struct module *mod,
1445 struct kernel_param *kparam,
1446 unsigned int num_params)
1450 err = mod_sysfs_init(mod);
1454 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1455 if (!mod->holders_dir) {
1460 err = module_param_sysfs_setup(mod, kparam, num_params);
1462 goto out_unreg_holders;
1464 err = module_add_modinfo_attrs(mod);
1466 goto out_unreg_param;
1468 add_usage_links(mod);
1470 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1474 module_param_sysfs_remove(mod);
1476 kobject_put(mod->holders_dir);
1478 kobject_put(&mod->mkobj.kobj);
1483 static void mod_sysfs_fini(struct module *mod)
1485 kobject_put(&mod->mkobj.kobj);
1488 #else /* CONFIG_SYSFS */
1490 static inline int mod_sysfs_init(struct module *mod)
1495 static inline int mod_sysfs_setup(struct module *mod,
1496 struct kernel_param *kparam,
1497 unsigned int num_params)
1502 static inline int module_add_modinfo_attrs(struct module *mod)
1507 static inline void module_remove_modinfo_attrs(struct module *mod)
1511 static void mod_sysfs_fini(struct module *mod)
1515 static void del_usage_links(struct module *mod)
1519 #endif /* CONFIG_SYSFS */
1521 static void mod_kobject_remove(struct module *mod)
1523 del_usage_links(mod);
1524 module_remove_modinfo_attrs(mod);
1525 module_param_sysfs_remove(mod);
1526 kobject_put(mod->mkobj.drivers_dir);
1527 kobject_put(mod->holders_dir);
1528 mod_sysfs_fini(mod);
1532 * unlink the module with the whole machine is stopped with interrupts off
1533 * - this defends against kallsyms not taking locks
1535 static int __unlink_module(void *_mod)
1537 struct module *mod = _mod;
1538 list_del(&mod->list);
1542 /* Free a module, remove from lists, etc. */
1543 static void free_module(struct module *mod)
1545 trace_module_free(mod);
1547 /* Delete from various lists */
1548 mutex_lock(&module_mutex);
1549 stop_machine(__unlink_module, mod, NULL);
1550 mutex_unlock(&module_mutex);
1551 remove_notes_attrs(mod);
1552 remove_sect_attrs(mod);
1553 mod_kobject_remove(mod);
1555 /* Remove dynamic debug info */
1556 ddebug_remove_module(mod->name);
1558 /* Arch-specific cleanup. */
1559 module_arch_cleanup(mod);
1561 /* Module unload stuff */
1562 module_unload_free(mod);
1564 /* Free any allocated parameters. */
1565 destroy_params(mod->kp, mod->num_kp);
1567 /* This may be NULL, but that's OK */
1568 module_free(mod, mod->module_init);
1570 percpu_modfree(mod);
1572 /* Free lock-classes: */
1573 lockdep_free_key_range(mod->module_core, mod->core_size);
1575 /* Finally, free the core (containing the module structure) */
1576 module_free(mod, mod->module_core);
1579 update_protections(current->mm);
1583 void *__symbol_get(const char *symbol)
1585 struct module *owner;
1586 const struct kernel_symbol *sym;
1589 sym = find_symbol(symbol, &owner, NULL, true, true);
1590 if (sym && strong_try_module_get(owner))
1594 return sym ? (void *)sym->value : NULL;
1596 EXPORT_SYMBOL_GPL(__symbol_get);
1599 * Ensure that an exported symbol [global namespace] does not already exist
1600 * in the kernel or in some other module's exported symbol table.
1602 * You must hold the module_mutex.
1604 static int verify_export_symbols(struct module *mod)
1607 struct module *owner;
1608 const struct kernel_symbol *s;
1610 const struct kernel_symbol *sym;
1613 { mod->syms, mod->num_syms },
1614 { mod->gpl_syms, mod->num_gpl_syms },
1615 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1616 #ifdef CONFIG_UNUSED_SYMBOLS
1617 { mod->unused_syms, mod->num_unused_syms },
1618 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1622 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1623 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1624 if (find_symbol(s->name, &owner, NULL, true, false)) {
1626 "%s: exports duplicate symbol %s"
1628 mod->name, s->name, module_name(owner));
1636 /* Change all symbols so that st_value encodes the pointer directly. */
1637 static int simplify_symbols(Elf_Shdr *sechdrs,
1638 unsigned int symindex,
1640 unsigned int versindex,
1641 unsigned int pcpuindex,
1644 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1645 unsigned long secbase;
1646 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1648 const struct kernel_symbol *ksym;
1650 for (i = 1; i < n; i++) {
1651 switch (sym[i].st_shndx) {
1653 /* We compiled with -fno-common. These are not
1654 supposed to happen. */
1655 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1656 printk("%s: please compile with -fno-common\n",
1662 /* Don't need to do anything */
1663 DEBUGP("Absolute symbol: 0x%08lx\n",
1664 (long)sym[i].st_value);
1668 ksym = resolve_symbol_wait(sechdrs, versindex,
1669 strtab + sym[i].st_name,
1671 /* Ok if resolved. */
1672 if (ksym && !IS_ERR(ksym)) {
1673 sym[i].st_value = ksym->value;
1678 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1681 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
1682 mod->name, strtab + sym[i].st_name,
1684 ret = PTR_ERR(ksym) ?: -ENOENT;
1688 /* Divert to percpu allocation if a percpu var. */
1689 if (sym[i].st_shndx == pcpuindex)
1690 secbase = (unsigned long)mod_percpu(mod);
1692 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1693 sym[i].st_value += secbase;
1701 static int apply_relocations(struct module *mod,
1704 unsigned int symindex,
1705 unsigned int strindex)
1710 /* Now do relocations. */
1711 for (i = 1; i < hdr->e_shnum; i++) {
1712 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1713 unsigned int info = sechdrs[i].sh_info;
1715 /* Not a valid relocation section? */
1716 if (info >= hdr->e_shnum)
1719 /* Don't bother with non-allocated sections */
1720 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1723 if (sechdrs[i].sh_type == SHT_REL)
1724 err = apply_relocate(sechdrs, strtab, symindex, i, mod);
1725 else if (sechdrs[i].sh_type == SHT_RELA)
1726 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1734 /* Additional bytes needed by arch in front of individual sections */
1735 unsigned int __weak arch_mod_section_prepend(struct module *mod,
1736 unsigned int section)
1738 /* default implementation just returns zero */
1742 /* Update size with this section: return offset. */
1743 static long get_offset(struct module *mod, unsigned int *size,
1744 Elf_Shdr *sechdr, unsigned int section)
1748 *size += arch_mod_section_prepend(mod, section);
1749 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1750 *size = ret + sechdr->sh_size;
1754 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1755 might -- code, read-only data, read-write data, small data. Tally
1756 sizes, and place the offsets into sh_entsize fields: high bit means it
1758 static void layout_sections(struct module *mod,
1759 const Elf_Ehdr *hdr,
1761 const char *secstrings)
1763 static unsigned long const masks[][2] = {
1764 /* NOTE: all executable code must be the first section
1765 * in this array; otherwise modify the text_size
1766 * finder in the two loops below */
1767 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1768 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1769 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1770 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1774 for (i = 0; i < hdr->e_shnum; i++)
1775 sechdrs[i].sh_entsize = ~0UL;
1777 DEBUGP("Core section allocation order:\n");
1778 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1779 for (i = 0; i < hdr->e_shnum; ++i) {
1780 Elf_Shdr *s = &sechdrs[i];
1782 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1783 || (s->sh_flags & masks[m][1])
1784 || s->sh_entsize != ~0UL
1785 || strstarts(secstrings + s->sh_name, ".init"))
1787 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1788 DEBUGP("\t%s\n", secstrings + s->sh_name);
1791 mod->core_text_size = mod->core_size;
1794 DEBUGP("Init section allocation order:\n");
1795 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1796 for (i = 0; i < hdr->e_shnum; ++i) {
1797 Elf_Shdr *s = &sechdrs[i];
1799 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1800 || (s->sh_flags & masks[m][1])
1801 || s->sh_entsize != ~0UL
1802 || !strstarts(secstrings + s->sh_name, ".init"))
1804 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1805 | INIT_OFFSET_MASK);
1806 DEBUGP("\t%s\n", secstrings + s->sh_name);
1809 mod->init_text_size = mod->init_size;
1813 static void set_license(struct module *mod, const char *license)
1816 license = "unspecified";
1818 if (!license_is_gpl_compatible(license)) {
1819 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1820 printk(KERN_WARNING "%s: module license '%s' taints "
1821 "kernel.\n", mod->name, license);
1822 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1826 /* Parse tag=value strings from .modinfo section */
1827 static char *next_string(char *string, unsigned long *secsize)
1829 /* Skip non-zero chars */
1832 if ((*secsize)-- <= 1)
1836 /* Skip any zero padding. */
1837 while (!string[0]) {
1839 if ((*secsize)-- <= 1)
1845 static char *get_modinfo(const Elf_Shdr *sechdrs,
1850 unsigned int taglen = strlen(tag);
1851 unsigned long size = sechdrs[info].sh_size;
1853 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1854 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1855 return p + taglen + 1;
1860 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1861 unsigned int infoindex)
1863 struct module_attribute *attr;
1866 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1869 get_modinfo(sechdrs,
1875 static void free_modinfo(struct module *mod)
1877 struct module_attribute *attr;
1880 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1886 #ifdef CONFIG_KALLSYMS
1888 /* lookup symbol in given range of kernel_symbols */
1889 static const struct kernel_symbol *lookup_symbol(const char *name,
1890 const struct kernel_symbol *start,
1891 const struct kernel_symbol *stop)
1893 const struct kernel_symbol *ks = start;
1894 for (; ks < stop; ks++)
1895 if (strcmp(ks->name, name) == 0)
1900 static int is_exported(const char *name, unsigned long value,
1901 const struct module *mod)
1903 const struct kernel_symbol *ks;
1905 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1907 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1908 return ks != NULL && ks->value == value;
1912 static char elf_type(const Elf_Sym *sym,
1914 const char *secstrings,
1917 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1918 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1923 if (sym->st_shndx == SHN_UNDEF)
1925 if (sym->st_shndx == SHN_ABS)
1927 if (sym->st_shndx >= SHN_LORESERVE)
1929 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1931 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1932 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1933 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1935 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1940 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1941 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1946 if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug"))
1951 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1954 const Elf_Shdr *sec;
1956 if (src->st_shndx == SHN_UNDEF
1957 || src->st_shndx >= shnum
1961 sec = sechdrs + src->st_shndx;
1962 if (!(sec->sh_flags & SHF_ALLOC)
1963 #ifndef CONFIG_KALLSYMS_ALL
1964 || !(sec->sh_flags & SHF_EXECINSTR)
1966 || (sec->sh_entsize & INIT_OFFSET_MASK))
1972 static unsigned long layout_symtab(struct module *mod,
1974 unsigned int symindex,
1975 unsigned int strindex,
1976 const Elf_Ehdr *hdr,
1977 const char *secstrings,
1978 unsigned long *pstroffs,
1979 unsigned long *strmap)
1981 unsigned long symoffs;
1982 Elf_Shdr *symsect = sechdrs + symindex;
1983 Elf_Shdr *strsect = sechdrs + strindex;
1986 unsigned int i, nsrc, ndst;
1988 /* Put symbol section at end of init part of module. */
1989 symsect->sh_flags |= SHF_ALLOC;
1990 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1991 symindex) | INIT_OFFSET_MASK;
1992 DEBUGP("\t%s\n", secstrings + symsect->sh_name);
1994 src = (void *)hdr + symsect->sh_offset;
1995 nsrc = symsect->sh_size / sizeof(*src);
1996 strtab = (void *)hdr + strsect->sh_offset;
1997 for (ndst = i = 1; i < nsrc; ++i, ++src)
1998 if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
1999 unsigned int j = src->st_name;
2001 while(!__test_and_set_bit(j, strmap) && strtab[j])
2006 /* Append room for core symbols at end of core part. */
2007 symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
2008 mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
2010 /* Put string table section at end of init part of module. */
2011 strsect->sh_flags |= SHF_ALLOC;
2012 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
2013 strindex) | INIT_OFFSET_MASK;
2014 DEBUGP("\t%s\n", secstrings + strsect->sh_name);
2016 /* Append room for core symbols' strings at end of core part. */
2017 *pstroffs = mod->core_size;
2018 __set_bit(0, strmap);
2019 mod->core_size += bitmap_weight(strmap, strsect->sh_size);
2024 static void add_kallsyms(struct module *mod,
2027 unsigned int symindex,
2028 unsigned int strindex,
2029 unsigned long symoffs,
2030 unsigned long stroffs,
2031 const char *secstrings,
2032 unsigned long *strmap)
2034 unsigned int i, ndst;
2039 mod->symtab = (void *)sechdrs[symindex].sh_addr;
2040 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
2041 mod->strtab = (void *)sechdrs[strindex].sh_addr;
2043 /* Set types up while we still have access to sections. */
2044 for (i = 0; i < mod->num_symtab; i++)
2045 mod->symtab[i].st_info
2046 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
2048 mod->core_symtab = dst = mod->module_core + symoffs;
2051 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
2052 if (!is_core_symbol(src, sechdrs, shnum))
2055 dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
2058 mod->core_num_syms = ndst;
2060 mod->core_strtab = s = mod->module_core + stroffs;
2061 for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i)
2062 if (test_bit(i, strmap))
2063 *++s = mod->strtab[i];
2066 static inline unsigned long layout_symtab(struct module *mod,
2068 unsigned int symindex,
2069 unsigned int strindex,
2070 const Elf_Ehdr *hdr,
2071 const char *secstrings,
2072 unsigned long *pstroffs,
2073 unsigned long *strmap)
2078 static inline void add_kallsyms(struct module *mod,
2081 unsigned int symindex,
2082 unsigned int strindex,
2083 unsigned long symoffs,
2084 unsigned long stroffs,
2085 const char *secstrings,
2086 const unsigned long *strmap)
2089 #endif /* CONFIG_KALLSYMS */
2091 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2093 #ifdef CONFIG_DYNAMIC_DEBUG
2094 if (ddebug_add_module(debug, num, debug->modname))
2095 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2100 static void dynamic_debug_remove(struct _ddebug *debug)
2103 ddebug_remove_module(debug->modname);
2106 static void *module_alloc_update_bounds(unsigned long size)
2108 void *ret = module_alloc(size);
2111 mutex_lock(&module_mutex);
2112 /* Update module bounds. */
2113 if ((unsigned long)ret < module_addr_min)
2114 module_addr_min = (unsigned long)ret;
2115 if ((unsigned long)ret + size > module_addr_max)
2116 module_addr_max = (unsigned long)ret + size;
2117 mutex_unlock(&module_mutex);
2122 #ifdef CONFIG_DEBUG_KMEMLEAK
2123 static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2124 const Elf_Shdr *sechdrs,
2125 const char *secstrings)
2129 /* only scan the sections containing data */
2130 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2132 for (i = 1; i < hdr->e_shnum; i++) {
2133 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2135 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
2136 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
2139 kmemleak_scan_area((void *)sechdrs[i].sh_addr,
2140 sechdrs[i].sh_size, GFP_KERNEL);
2144 static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2146 const char *secstrings)
2151 static int copy_and_check(Elf_Ehdr **hdrp,
2152 const void __user *umod, unsigned long len)
2157 if (len < sizeof(*hdr))
2160 /* Suck in entire file: we'll want most of it. */
2161 /* vmalloc barfs on "unusual" numbers. Check here */
2162 if (len > 64 * 1024 * 1024 || (hdr = *hdrp = vmalloc(len)) == NULL)
2165 if (copy_from_user(hdr, umod, len) != 0) {
2170 /* Sanity checks against insmoding binaries or wrong arch,
2171 weird elf version */
2172 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
2173 || hdr->e_type != ET_REL
2174 || !elf_check_arch(hdr)
2175 || hdr->e_shentsize != sizeof(Elf_Shdr)) {
2180 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
2191 static int check_modinfo(struct module *mod,
2192 const Elf_Shdr *sechdrs,
2193 unsigned int infoindex, unsigned int versindex)
2195 const char *modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2198 /* This is allowed: modprobe --force will invalidate it. */
2200 err = try_to_force_load(mod, "bad vermagic");
2203 } else if (!same_magic(modmagic, vermagic, versindex)) {
2204 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2205 mod->name, modmagic, vermagic);
2209 if (get_modinfo(sechdrs, infoindex, "staging")) {
2210 add_taint_module(mod, TAINT_CRAP);
2211 printk(KERN_WARNING "%s: module is from the staging directory,"
2212 " the quality is unknown, you have been warned.\n",
2216 /* Set up license info based on the info section */
2217 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2222 static void find_module_sections(struct module *mod, Elf_Ehdr *hdr,
2223 Elf_Shdr *sechdrs, const char *secstrings)
2225 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2226 sizeof(*mod->kp), &mod->num_kp);
2227 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2228 sizeof(*mod->syms), &mod->num_syms);
2229 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2230 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2231 sizeof(*mod->gpl_syms),
2232 &mod->num_gpl_syms);
2233 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2234 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2235 "__ksymtab_gpl_future",
2236 sizeof(*mod->gpl_future_syms),
2237 &mod->num_gpl_future_syms);
2238 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2239 "__kcrctab_gpl_future");
2241 #ifdef CONFIG_UNUSED_SYMBOLS
2242 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2244 sizeof(*mod->unused_syms),
2245 &mod->num_unused_syms);
2246 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2247 "__kcrctab_unused");
2248 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2249 "__ksymtab_unused_gpl",
2250 sizeof(*mod->unused_gpl_syms),
2251 &mod->num_unused_gpl_syms);
2252 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2253 "__kcrctab_unused_gpl");
2255 #ifdef CONFIG_CONSTRUCTORS
2256 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2257 sizeof(*mod->ctors), &mod->num_ctors);
2260 #ifdef CONFIG_TRACEPOINTS
2261 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2263 sizeof(*mod->tracepoints),
2264 &mod->num_tracepoints);
2266 #ifdef CONFIG_EVENT_TRACING
2267 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2269 sizeof(*mod->trace_events),
2270 &mod->num_trace_events);
2272 * This section contains pointers to allocated objects in the trace
2273 * code and not scanning it leads to false positives.
2275 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2276 mod->num_trace_events, GFP_KERNEL);
2278 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2279 /* sechdrs[0].sh_size is always zero */
2280 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2282 sizeof(*mod->ftrace_callsites),
2283 &mod->num_ftrace_callsites);
2286 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2287 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2291 static struct module *move_module(struct module *mod,
2292 Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
2293 const char *secstrings, unsigned modindex)
2298 /* Do the allocs. */
2299 ptr = module_alloc_update_bounds(mod->core_size);
2301 * The pointer to this block is stored in the module structure
2302 * which is inside the block. Just mark it as not being a
2305 kmemleak_not_leak(ptr);
2307 return ERR_PTR(-ENOMEM);
2309 memset(ptr, 0, mod->core_size);
2310 mod->module_core = ptr;
2312 ptr = module_alloc_update_bounds(mod->init_size);
2314 * The pointer to this block is stored in the module structure
2315 * which is inside the block. This block doesn't need to be
2316 * scanned as it contains data and code that will be freed
2317 * after the module is initialized.
2319 kmemleak_ignore(ptr);
2320 if (!ptr && mod->init_size) {
2321 module_free(mod, mod->module_core);
2322 return ERR_PTR(-ENOMEM);
2324 memset(ptr, 0, mod->init_size);
2325 mod->module_init = ptr;
2327 /* Transfer each section which specifies SHF_ALLOC */
2328 DEBUGP("final section addresses:\n");
2329 for (i = 0; i < hdr->e_shnum; i++) {
2332 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2335 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2336 dest = mod->module_init
2337 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2339 dest = mod->module_core + sechdrs[i].sh_entsize;
2341 if (sechdrs[i].sh_type != SHT_NOBITS)
2342 memcpy(dest, (void *)sechdrs[i].sh_addr,
2343 sechdrs[i].sh_size);
2344 /* Update sh_addr to point to copy in image. */
2345 sechdrs[i].sh_addr = (unsigned long)dest;
2346 DEBUGP("\t0x%lx %s\n",
2347 sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2349 /* Module has been moved. */
2350 mod = (void *)sechdrs[modindex].sh_addr;
2351 kmemleak_load_module(mod, hdr, sechdrs, secstrings);
2355 static int check_module_license_and_versions(struct module *mod,
2359 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2360 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2361 * using GPL-only symbols it needs.
2363 if (strcmp(mod->name, "ndiswrapper") == 0)
2364 add_taint(TAINT_PROPRIETARY_MODULE);
2366 /* driverloader was caught wrongly pretending to be under GPL */
2367 if (strcmp(mod->name, "driverloader") == 0)
2368 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2370 #ifdef CONFIG_MODVERSIONS
2371 if ((mod->num_syms && !mod->crcs)
2372 || (mod->num_gpl_syms && !mod->gpl_crcs)
2373 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2374 #ifdef CONFIG_UNUSED_SYMBOLS
2375 || (mod->num_unused_syms && !mod->unused_crcs)
2376 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2379 return try_to_force_load(mod,
2380 "no versions for exported symbols");
2386 static void flush_module_icache(const struct module *mod)
2388 mm_segment_t old_fs;
2390 /* flush the icache in correct context */
2395 * Flush the instruction cache, since we've played with text.
2396 * Do it before processing of module parameters, so the module
2397 * can provide parameter accessor functions of its own.
2399 if (mod->module_init)
2400 flush_icache_range((unsigned long)mod->module_init,
2401 (unsigned long)mod->module_init
2403 flush_icache_range((unsigned long)mod->module_core,
2404 (unsigned long)mod->module_core + mod->core_size);
2409 /* Allocate and load the module: note that size of section 0 is always
2410 zero, and we rely on this for optional sections. */
2411 static noinline struct module *load_module(void __user *umod,
2413 const char __user *uargs)
2417 char *secstrings, *args, *strtab = NULL;
2419 unsigned int symindex = 0;
2420 unsigned int strindex = 0;
2421 unsigned int modindex, versindex, infoindex, pcpuindex;
2424 unsigned long symoffs, stroffs, *strmap;
2425 void __percpu *percpu;
2426 struct _ddebug *debug = NULL;
2427 unsigned int num_debug = 0;
2429 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2432 err = copy_and_check(&hdr, umod, len);
2434 return ERR_PTR(err);
2436 /* Convenience variables */
2437 sechdrs = (void *)hdr + hdr->e_shoff;
2438 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
2439 sechdrs[0].sh_addr = 0;
2441 for (i = 1; i < hdr->e_shnum; i++) {
2442 if (sechdrs[i].sh_type != SHT_NOBITS
2443 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
2446 /* Mark all sections sh_addr with their address in the
2448 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
2450 /* Internal symbols and strings. */
2451 if (sechdrs[i].sh_type == SHT_SYMTAB) {
2453 strindex = sechdrs[i].sh_link;
2454 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
2456 #ifndef CONFIG_MODULE_UNLOAD
2457 /* Don't load .exit sections */
2458 if (strstarts(secstrings+sechdrs[i].sh_name, ".exit"))
2459 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
2463 modindex = find_sec(hdr, sechdrs, secstrings,
2464 ".gnu.linkonce.this_module");
2466 printk(KERN_WARNING "No module found in object\n");
2470 /* This is temporary: point mod into copy of data. */
2471 mod = (void *)sechdrs[modindex].sh_addr;
2473 if (symindex == 0) {
2474 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2480 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
2481 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
2482 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
2484 /* Don't keep modinfo and version sections. */
2485 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2486 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2488 /* Check module struct version now, before we try to use module. */
2489 if (!check_modstruct_version(sechdrs, versindex, mod)) {
2494 err = check_modinfo(mod, sechdrs, infoindex, versindex);
2498 /* Now copy in args */
2499 args = strndup_user(uargs, ~0UL >> 1);
2501 err = PTR_ERR(args);
2505 strmap = kzalloc(BITS_TO_LONGS(sechdrs[strindex].sh_size)
2506 * sizeof(long), GFP_KERNEL);
2512 mod->state = MODULE_STATE_COMING;
2514 /* Allow arches to frob section contents and sizes. */
2515 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
2520 /* We have a special allocation for this section. */
2521 err = percpu_modalloc(mod, sechdrs[pcpuindex].sh_size,
2522 sechdrs[pcpuindex].sh_addralign);
2525 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2527 /* Keep this around for failure path. */
2528 percpu = mod_percpu(mod);
2530 /* Determine total sizes, and put offsets in sh_entsize. For now
2531 this is done generically; there doesn't appear to be any
2532 special cases for the architectures. */
2533 layout_sections(mod, hdr, sechdrs, secstrings);
2534 symoffs = layout_symtab(mod, sechdrs, symindex, strindex, hdr,
2535 secstrings, &stroffs, strmap);
2537 /* Allocate and move to the final place */
2538 mod = move_module(mod, hdr, sechdrs, secstrings, modindex);
2544 /* Now we've moved module, initialize linked lists, etc. */
2545 err = module_unload_init(mod);
2549 /* Now we've got everything in the final locations, we can
2550 * find optional sections. */
2551 find_module_sections(mod, hdr, sechdrs, secstrings);
2553 err = check_module_license_and_versions(mod, sechdrs);
2557 /* Set up MODINFO_ATTR fields */
2558 setup_modinfo(mod, sechdrs, infoindex);
2560 /* Fix up syms, so that st_value is a pointer to location. */
2561 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2566 err = apply_relocations(mod, hdr, sechdrs, symindex, strindex);
2570 /* Set up and sort exception table */
2571 mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
2572 sizeof(*mod->extable), &mod->num_exentries);
2573 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2575 /* Finally, copy percpu area over. */
2576 percpu_modcopy(mod, (void *)sechdrs[pcpuindex].sh_addr,
2577 sechdrs[pcpuindex].sh_size);
2579 add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex,
2580 symoffs, stroffs, secstrings, strmap);
2585 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2586 sizeof(*debug), &num_debug);
2588 err = module_finalize(hdr, sechdrs, mod);
2592 flush_module_icache(mod);
2596 /* Now sew it into the lists so we can get lockdep and oops
2597 * info during argument parsing. Noone should access us, since
2598 * strong_try_module_get() will fail.
2599 * lockdep/oops can run asynchronous, so use the RCU list insertion
2600 * function to insert in a way safe to concurrent readers.
2601 * The mutex protects against concurrent writers.
2603 mutex_lock(&module_mutex);
2604 if (find_module(mod->name)) {
2610 dynamic_debug_setup(debug, num_debug);
2612 /* Find duplicate symbols */
2613 err = verify_export_symbols(mod);
2617 list_add_rcu(&mod->list, &modules);
2618 mutex_unlock(&module_mutex);
2620 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2624 err = mod_sysfs_setup(mod, mod->kp, mod->num_kp);
2628 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2629 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2631 /* Get rid of temporary copy */
2634 trace_module_load(mod);
2640 mutex_lock(&module_mutex);
2641 /* Unlink carefully: kallsyms could be walking list. */
2642 list_del_rcu(&mod->list);
2644 dynamic_debug_remove(debug);
2646 mutex_unlock(&module_mutex);
2647 synchronize_sched();
2648 module_arch_cleanup(mod);
2652 module_unload_free(mod);
2654 module_free(mod, mod->module_init);
2655 module_free(mod, mod->module_core);
2656 /* mod will be freed with core. Don't access it beyond this line! */
2658 free_percpu(percpu);
2664 return ERR_PTR(err);
2667 printk(KERN_ERR "Module len %lu truncated\n", len);
2672 /* Call module constructors. */
2673 static void do_mod_ctors(struct module *mod)
2675 #ifdef CONFIG_CONSTRUCTORS
2678 for (i = 0; i < mod->num_ctors; i++)
2683 /* This is where the real work happens */
2684 SYSCALL_DEFINE3(init_module, void __user *, umod,
2685 unsigned long, len, const char __user *, uargs)
2690 /* Must have permission */
2691 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2694 /* Do all the hard work */
2695 mod = load_module(umod, len, uargs);
2697 return PTR_ERR(mod);
2699 blocking_notifier_call_chain(&module_notify_list,
2700 MODULE_STATE_COMING, mod);
2703 /* Start the module */
2704 if (mod->init != NULL)
2705 ret = do_one_initcall(mod->init);
2707 /* Init routine failed: abort. Try to protect us from
2708 buggy refcounters. */
2709 mod->state = MODULE_STATE_GOING;
2710 synchronize_sched();
2712 blocking_notifier_call_chain(&module_notify_list,
2713 MODULE_STATE_GOING, mod);
2715 wake_up(&module_wq);
2720 "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2721 "%s: loading module anyway...\n",
2722 __func__, mod->name, ret,
2727 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2728 mod->state = MODULE_STATE_LIVE;
2729 wake_up(&module_wq);
2730 blocking_notifier_call_chain(&module_notify_list,
2731 MODULE_STATE_LIVE, mod);
2733 /* We need to finish all async code before the module init sequence is done */
2734 async_synchronize_full();
2736 mutex_lock(&module_mutex);
2737 /* Drop initial reference. */
2739 trim_init_extable(mod);
2740 #ifdef CONFIG_KALLSYMS
2741 mod->num_symtab = mod->core_num_syms;
2742 mod->symtab = mod->core_symtab;
2743 mod->strtab = mod->core_strtab;
2745 module_free(mod, mod->module_init);
2746 mod->module_init = NULL;
2748 mod->init_text_size = 0;
2749 mutex_unlock(&module_mutex);
2754 static inline int within(unsigned long addr, void *start, unsigned long size)
2756 return ((void *)addr >= start && (void *)addr < start + size);
2759 #ifdef CONFIG_KALLSYMS
2761 * This ignores the intensely annoying "mapping symbols" found
2762 * in ARM ELF files: $a, $t and $d.
2764 static inline int is_arm_mapping_symbol(const char *str)
2766 return str[0] == '$' && strchr("atd", str[1])
2767 && (str[2] == '\0' || str[2] == '.');
2770 static const char *get_ksymbol(struct module *mod,
2772 unsigned long *size,
2773 unsigned long *offset)
2775 unsigned int i, best = 0;
2776 unsigned long nextval;
2778 /* At worse, next value is at end of module */
2779 if (within_module_init(addr, mod))
2780 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2782 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2784 /* Scan for closest preceeding symbol, and next symbol. (ELF
2785 starts real symbols at 1). */
2786 for (i = 1; i < mod->num_symtab; i++) {
2787 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2790 /* We ignore unnamed symbols: they're uninformative
2791 * and inserted at a whim. */
2792 if (mod->symtab[i].st_value <= addr
2793 && mod->symtab[i].st_value > mod->symtab[best].st_value
2794 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2795 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2797 if (mod->symtab[i].st_value > addr
2798 && mod->symtab[i].st_value < nextval
2799 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2800 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2801 nextval = mod->symtab[i].st_value;
2808 *size = nextval - mod->symtab[best].st_value;
2810 *offset = addr - mod->symtab[best].st_value;
2811 return mod->strtab + mod->symtab[best].st_name;
2814 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2815 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2816 const char *module_address_lookup(unsigned long addr,
2817 unsigned long *size,
2818 unsigned long *offset,
2823 const char *ret = NULL;
2826 list_for_each_entry_rcu(mod, &modules, list) {
2827 if (within_module_init(addr, mod) ||
2828 within_module_core(addr, mod)) {
2830 *modname = mod->name;
2831 ret = get_ksymbol(mod, addr, size, offset);
2835 /* Make a copy in here where it's safe */
2837 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2844 int lookup_module_symbol_name(unsigned long addr, char *symname)
2849 list_for_each_entry_rcu(mod, &modules, list) {
2850 if (within_module_init(addr, mod) ||
2851 within_module_core(addr, mod)) {
2854 sym = get_ksymbol(mod, addr, NULL, NULL);
2857 strlcpy(symname, sym, KSYM_NAME_LEN);
2867 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2868 unsigned long *offset, char *modname, char *name)
2873 list_for_each_entry_rcu(mod, &modules, list) {
2874 if (within_module_init(addr, mod) ||
2875 within_module_core(addr, mod)) {
2878 sym = get_ksymbol(mod, addr, size, offset);
2882 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2884 strlcpy(name, sym, KSYM_NAME_LEN);
2894 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2895 char *name, char *module_name, int *exported)
2900 list_for_each_entry_rcu(mod, &modules, list) {
2901 if (symnum < mod->num_symtab) {
2902 *value = mod->symtab[symnum].st_value;
2903 *type = mod->symtab[symnum].st_info;
2904 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2906 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2907 *exported = is_exported(name, *value, mod);
2911 symnum -= mod->num_symtab;
2917 static unsigned long mod_find_symname(struct module *mod, const char *name)
2921 for (i = 0; i < mod->num_symtab; i++)
2922 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2923 mod->symtab[i].st_info != 'U')
2924 return mod->symtab[i].st_value;
2928 /* Look for this name: can be of form module:name. */
2929 unsigned long module_kallsyms_lookup_name(const char *name)
2933 unsigned long ret = 0;
2935 /* Don't lock: we're in enough trouble already. */
2937 if ((colon = strchr(name, ':')) != NULL) {
2939 if ((mod = find_module(name)) != NULL)
2940 ret = mod_find_symname(mod, colon+1);
2943 list_for_each_entry_rcu(mod, &modules, list)
2944 if ((ret = mod_find_symname(mod, name)) != 0)
2951 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
2952 struct module *, unsigned long),
2959 list_for_each_entry(mod, &modules, list) {
2960 for (i = 0; i < mod->num_symtab; i++) {
2961 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
2962 mod, mod->symtab[i].st_value);
2969 #endif /* CONFIG_KALLSYMS */
2971 static char *module_flags(struct module *mod, char *buf)
2976 mod->state == MODULE_STATE_GOING ||
2977 mod->state == MODULE_STATE_COMING) {
2979 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2981 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2983 if (mod->taints & (1 << TAINT_CRAP))
2986 * TAINT_FORCED_RMMOD: could be added.
2987 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2991 /* Show a - for module-is-being-unloaded */
2992 if (mod->state == MODULE_STATE_GOING)
2994 /* Show a + for module-is-being-loaded */
2995 if (mod->state == MODULE_STATE_COMING)
3004 #ifdef CONFIG_PROC_FS
3005 /* Called by the /proc file system to return a list of modules. */
3006 static void *m_start(struct seq_file *m, loff_t *pos)
3008 mutex_lock(&module_mutex);
3009 return seq_list_start(&modules, *pos);
3012 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3014 return seq_list_next(p, &modules, pos);
3017 static void m_stop(struct seq_file *m, void *p)
3019 mutex_unlock(&module_mutex);
3022 static int m_show(struct seq_file *m, void *p)
3024 struct module *mod = list_entry(p, struct module, list);
3027 seq_printf(m, "%s %u",
3028 mod->name, mod->init_size + mod->core_size);
3029 print_unload_info(m, mod);
3031 /* Informative for users. */
3032 seq_printf(m, " %s",
3033 mod->state == MODULE_STATE_GOING ? "Unloading":
3034 mod->state == MODULE_STATE_COMING ? "Loading":
3036 /* Used by oprofile and other similar tools. */
3037 seq_printf(m, " 0x%p", mod->module_core);
3041 seq_printf(m, " %s", module_flags(mod, buf));
3043 seq_printf(m, "\n");
3047 /* Format: modulename size refcount deps address
3049 Where refcount is a number or -, and deps is a comma-separated list
3052 static const struct seq_operations modules_op = {
3059 static int modules_open(struct inode *inode, struct file *file)
3061 return seq_open(file, &modules_op);
3064 static const struct file_operations proc_modules_operations = {
3065 .open = modules_open,
3067 .llseek = seq_lseek,
3068 .release = seq_release,
3071 static int __init proc_modules_init(void)
3073 proc_create("modules", 0, NULL, &proc_modules_operations);
3076 module_init(proc_modules_init);
3079 /* Given an address, look for it in the module exception tables. */
3080 const struct exception_table_entry *search_module_extables(unsigned long addr)
3082 const struct exception_table_entry *e = NULL;
3086 list_for_each_entry_rcu(mod, &modules, list) {
3087 if (mod->num_exentries == 0)
3090 e = search_extable(mod->extable,
3091 mod->extable + mod->num_exentries - 1,
3098 /* Now, if we found one, we are running inside it now, hence
3099 we cannot unload the module, hence no refcnt needed. */
3104 * is_module_address - is this address inside a module?
3105 * @addr: the address to check.
3107 * See is_module_text_address() if you simply want to see if the address
3108 * is code (not data).
3110 bool is_module_address(unsigned long addr)
3115 ret = __module_address(addr) != NULL;
3122 * __module_address - get the module which contains an address.
3123 * @addr: the address.
3125 * Must be called with preempt disabled or module mutex held so that
3126 * module doesn't get freed during this.
3128 struct module *__module_address(unsigned long addr)
3132 if (addr < module_addr_min || addr > module_addr_max)
3135 list_for_each_entry_rcu(mod, &modules, list)
3136 if (within_module_core(addr, mod)
3137 || within_module_init(addr, mod))
3141 EXPORT_SYMBOL_GPL(__module_address);
3144 * is_module_text_address - is this address inside module code?
3145 * @addr: the address to check.
3147 * See is_module_address() if you simply want to see if the address is
3148 * anywhere in a module. See kernel_text_address() for testing if an
3149 * address corresponds to kernel or module code.
3151 bool is_module_text_address(unsigned long addr)
3156 ret = __module_text_address(addr) != NULL;
3163 * __module_text_address - get the module whose code contains an address.
3164 * @addr: the address.
3166 * Must be called with preempt disabled or module mutex held so that
3167 * module doesn't get freed during this.
3169 struct module *__module_text_address(unsigned long addr)
3171 struct module *mod = __module_address(addr);
3173 /* Make sure it's within the text section. */
3174 if (!within(addr, mod->module_init, mod->init_text_size)
3175 && !within(addr, mod->module_core, mod->core_text_size))
3180 EXPORT_SYMBOL_GPL(__module_text_address);
3182 /* Don't grab lock, we're oopsing. */
3183 void print_modules(void)
3188 printk(KERN_DEFAULT "Modules linked in:");
3189 /* Most callers should already have preempt disabled, but make sure */
3191 list_for_each_entry_rcu(mod, &modules, list)
3192 printk(" %s%s", mod->name, module_flags(mod, buf));
3194 if (last_unloaded_module[0])
3195 printk(" [last unloaded: %s]", last_unloaded_module);
3199 #ifdef CONFIG_MODVERSIONS
3200 /* Generate the signature for all relevant module structures here.
3201 * If these change, we don't want to try to parse the module. */
3202 void module_layout(struct module *mod,
3203 struct modversion_info *ver,
3204 struct kernel_param *kp,
3205 struct kernel_symbol *ks,
3206 struct tracepoint *tp)
3209 EXPORT_SYMBOL(module_layout);
3212 #ifdef CONFIG_TRACEPOINTS
3213 void module_update_tracepoints(void)
3217 mutex_lock(&module_mutex);
3218 list_for_each_entry(mod, &modules, list)
3220 tracepoint_update_probe_range(mod->tracepoints,
3221 mod->tracepoints + mod->num_tracepoints);
3222 mutex_unlock(&module_mutex);
3226 * Returns 0 if current not found.
3227 * Returns 1 if current found.
3229 int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3231 struct module *iter_mod;
3234 mutex_lock(&module_mutex);
3235 list_for_each_entry(iter_mod, &modules, list) {
3236 if (!iter_mod->taints) {
3238 * Sorted module list
3240 if (iter_mod < iter->module)
3242 else if (iter_mod > iter->module)
3243 iter->tracepoint = NULL;
3244 found = tracepoint_get_iter_range(&iter->tracepoint,
3245 iter_mod->tracepoints,
3246 iter_mod->tracepoints
3247 + iter_mod->num_tracepoints);
3249 iter->module = iter_mod;
3254 mutex_unlock(&module_mutex);