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/init.h>
22 #include <linux/kernel.h>
23 #include <linux/slab.h>
24 #include <linux/vmalloc.h>
25 #include <linux/elf.h>
26 #include <linux/seq_file.h>
27 #include <linux/syscalls.h>
28 #include <linux/fcntl.h>
29 #include <linux/rcupdate.h>
30 #include <linux/capability.h>
31 #include <linux/cpu.h>
32 #include <linux/moduleparam.h>
33 #include <linux/errno.h>
34 #include <linux/err.h>
35 #include <linux/vermagic.h>
36 #include <linux/notifier.h>
37 #include <linux/sched.h>
38 #include <linux/stop_machine.h>
39 #include <linux/device.h>
40 #include <linux/string.h>
41 #include <linux/mutex.h>
42 #include <linux/unwind.h>
43 #include <asm/uaccess.h>
44 #include <asm/semaphore.h>
45 #include <asm/cacheflush.h>
46 #include <linux/license.h>
51 #define DEBUGP(fmt , a...)
54 #ifndef ARCH_SHF_SMALL
55 #define ARCH_SHF_SMALL 0
58 /* If this is set, the section belongs in the init part of the module */
59 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
61 /* Protects module list */
62 static DEFINE_SPINLOCK(modlist_lock);
64 /* List of modules, protected by module_mutex AND modlist_lock */
65 static DEFINE_MUTEX(module_mutex);
66 static LIST_HEAD(modules);
68 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
70 int register_module_notifier(struct notifier_block * nb)
72 return blocking_notifier_chain_register(&module_notify_list, nb);
74 EXPORT_SYMBOL(register_module_notifier);
76 int unregister_module_notifier(struct notifier_block * nb)
78 return blocking_notifier_chain_unregister(&module_notify_list, nb);
80 EXPORT_SYMBOL(unregister_module_notifier);
82 /* We require a truly strong try_module_get() */
83 static inline int strong_try_module_get(struct module *mod)
85 if (mod && mod->state == MODULE_STATE_COMING)
87 return try_module_get(mod);
90 static inline void add_taint_module(struct module *mod, unsigned flag)
96 /* A thread that wants to hold a reference to a module only while it
97 * is running can call ths to safely exit.
98 * nfsd and lockd use this.
100 void __module_put_and_exit(struct module *mod, long code)
105 EXPORT_SYMBOL(__module_put_and_exit);
107 /* Find a module section: 0 means not found. */
108 static unsigned int find_sec(Elf_Ehdr *hdr,
110 const char *secstrings,
115 for (i = 1; i < hdr->e_shnum; i++)
116 /* Alloc bit cleared means "ignore it." */
117 if ((sechdrs[i].sh_flags & SHF_ALLOC)
118 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
123 /* Provided by the linker */
124 extern const struct kernel_symbol __start___ksymtab[];
125 extern const struct kernel_symbol __stop___ksymtab[];
126 extern const struct kernel_symbol __start___ksymtab_gpl[];
127 extern const struct kernel_symbol __stop___ksymtab_gpl[];
128 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
129 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
130 extern const struct kernel_symbol __start___ksymtab_unused[];
131 extern const struct kernel_symbol __stop___ksymtab_unused[];
132 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
133 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
134 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
135 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
136 extern const unsigned long __start___kcrctab[];
137 extern const unsigned long __start___kcrctab_gpl[];
138 extern const unsigned long __start___kcrctab_gpl_future[];
139 extern const unsigned long __start___kcrctab_unused[];
140 extern const unsigned long __start___kcrctab_unused_gpl[];
142 #ifndef CONFIG_MODVERSIONS
143 #define symversion(base, idx) NULL
145 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
148 /* lookup symbol in given range of kernel_symbols */
149 static const struct kernel_symbol *lookup_symbol(const char *name,
150 const struct kernel_symbol *start,
151 const struct kernel_symbol *stop)
153 const struct kernel_symbol *ks = start;
154 for (; ks < stop; ks++)
155 if (strcmp(ks->name, name) == 0)
160 static void printk_unused_warning(const char *name)
162 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
163 "however this module is using it.\n", name);
164 printk(KERN_WARNING "This symbol will go away in the future.\n");
165 printk(KERN_WARNING "Please evalute if this is the right api to use, "
166 "and if it really is, submit a report the linux kernel "
167 "mailinglist together with submitting your code for "
171 /* Find a symbol, return value, crc and module which owns it */
172 static unsigned long __find_symbol(const char *name,
173 struct module **owner,
174 const unsigned long **crc,
178 const struct kernel_symbol *ks;
180 /* Core kernel first. */
182 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
184 *crc = symversion(__start___kcrctab, (ks - __start___ksymtab));
188 ks = lookup_symbol(name, __start___ksymtab_gpl,
189 __stop___ksymtab_gpl);
191 *crc = symversion(__start___kcrctab_gpl,
192 (ks - __start___ksymtab_gpl));
196 ks = lookup_symbol(name, __start___ksymtab_gpl_future,
197 __stop___ksymtab_gpl_future);
200 printk(KERN_WARNING "Symbol %s is being used "
201 "by a non-GPL module, which will not "
202 "be allowed in the future\n", name);
203 printk(KERN_WARNING "Please see the file "
204 "Documentation/feature-removal-schedule.txt "
205 "in the kernel source tree for more "
208 *crc = symversion(__start___kcrctab_gpl_future,
209 (ks - __start___ksymtab_gpl_future));
213 ks = lookup_symbol(name, __start___ksymtab_unused,
214 __stop___ksymtab_unused);
216 printk_unused_warning(name);
217 *crc = symversion(__start___kcrctab_unused,
218 (ks - __start___ksymtab_unused));
223 ks = lookup_symbol(name, __start___ksymtab_unused_gpl,
224 __stop___ksymtab_unused_gpl);
226 printk_unused_warning(name);
227 *crc = symversion(__start___kcrctab_unused_gpl,
228 (ks - __start___ksymtab_unused_gpl));
232 /* Now try modules. */
233 list_for_each_entry(mod, &modules, list) {
235 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
237 *crc = symversion(mod->crcs, (ks - mod->syms));
242 ks = lookup_symbol(name, mod->gpl_syms,
243 mod->gpl_syms + mod->num_gpl_syms);
245 *crc = symversion(mod->gpl_crcs,
246 (ks - mod->gpl_syms));
250 ks = lookup_symbol(name, mod->unused_syms, mod->unused_syms + mod->num_unused_syms);
252 printk_unused_warning(name);
253 *crc = symversion(mod->unused_crcs, (ks - mod->unused_syms));
258 ks = lookup_symbol(name, mod->unused_gpl_syms,
259 mod->unused_gpl_syms + mod->num_unused_gpl_syms);
261 printk_unused_warning(name);
262 *crc = symversion(mod->unused_gpl_crcs,
263 (ks - mod->unused_gpl_syms));
267 ks = lookup_symbol(name, mod->gpl_future_syms,
268 (mod->gpl_future_syms +
269 mod->num_gpl_future_syms));
272 printk(KERN_WARNING "Symbol %s is being used "
273 "by a non-GPL module, which will not "
274 "be allowed in the future\n", name);
275 printk(KERN_WARNING "Please see the file "
276 "Documentation/feature-removal-schedule.txt "
277 "in the kernel source tree for more "
280 *crc = symversion(mod->gpl_future_crcs,
281 (ks - mod->gpl_future_syms));
285 DEBUGP("Failed to find symbol %s\n", name);
289 /* Search for module by name: must hold module_mutex. */
290 static struct module *find_module(const char *name)
294 list_for_each_entry(mod, &modules, list) {
295 if (strcmp(mod->name, name) == 0)
302 /* Number of blocks used and allocated. */
303 static unsigned int pcpu_num_used, pcpu_num_allocated;
304 /* Size of each block. -ve means used. */
305 static int *pcpu_size;
307 static int split_block(unsigned int i, unsigned short size)
309 /* Reallocation required? */
310 if (pcpu_num_used + 1 > pcpu_num_allocated) {
311 int *new = kmalloc(sizeof(new[0]) * pcpu_num_allocated*2,
316 memcpy(new, pcpu_size, sizeof(new[0])*pcpu_num_allocated);
317 pcpu_num_allocated *= 2;
322 /* Insert a new subblock */
323 memmove(&pcpu_size[i+1], &pcpu_size[i],
324 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
327 pcpu_size[i+1] -= size;
332 static inline unsigned int block_size(int val)
339 /* Created by linker magic */
340 extern char __per_cpu_start[], __per_cpu_end[];
342 static void *percpu_modalloc(unsigned long size, unsigned long align,
349 if (align > SMP_CACHE_BYTES) {
350 printk(KERN_WARNING "%s: per-cpu alignment %li > %i\n",
351 name, align, SMP_CACHE_BYTES);
352 align = SMP_CACHE_BYTES;
355 ptr = __per_cpu_start;
356 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
357 /* Extra for alignment requirement. */
358 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
359 BUG_ON(i == 0 && extra != 0);
361 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
364 /* Transfer extra to previous block. */
365 if (pcpu_size[i-1] < 0)
366 pcpu_size[i-1] -= extra;
368 pcpu_size[i-1] += extra;
369 pcpu_size[i] -= extra;
372 /* Split block if warranted */
373 if (pcpu_size[i] - size > sizeof(unsigned long))
374 if (!split_block(i, size))
378 pcpu_size[i] = -pcpu_size[i];
382 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
387 static void percpu_modfree(void *freeme)
390 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
392 /* First entry is core kernel percpu data. */
393 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
395 pcpu_size[i] = -pcpu_size[i];
402 /* Merge with previous? */
403 if (pcpu_size[i-1] >= 0) {
404 pcpu_size[i-1] += pcpu_size[i];
406 memmove(&pcpu_size[i], &pcpu_size[i+1],
407 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
410 /* Merge with next? */
411 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
412 pcpu_size[i] += pcpu_size[i+1];
414 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
415 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
419 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
421 const char *secstrings)
423 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
426 static int percpu_modinit(void)
429 pcpu_num_allocated = 2;
430 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
432 /* Static in-kernel percpu data (used). */
433 pcpu_size[0] = -ALIGN(__per_cpu_end-__per_cpu_start, SMP_CACHE_BYTES);
435 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
436 if (pcpu_size[1] < 0) {
437 printk(KERN_ERR "No per-cpu room for modules.\n");
443 __initcall(percpu_modinit);
444 #else /* ... !CONFIG_SMP */
445 static inline void *percpu_modalloc(unsigned long size, unsigned long align,
450 static inline void percpu_modfree(void *pcpuptr)
454 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
456 const char *secstrings)
460 static inline void percpu_modcopy(void *pcpudst, const void *src,
463 /* pcpusec should be 0, and size of that section should be 0. */
466 #endif /* CONFIG_SMP */
468 #define MODINFO_ATTR(field) \
469 static void setup_modinfo_##field(struct module *mod, const char *s) \
471 mod->field = kstrdup(s, GFP_KERNEL); \
473 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
474 struct module *mod, char *buffer) \
476 return sprintf(buffer, "%s\n", mod->field); \
478 static int modinfo_##field##_exists(struct module *mod) \
480 return mod->field != NULL; \
482 static void free_modinfo_##field(struct module *mod) \
487 static struct module_attribute modinfo_##field = { \
488 .attr = { .name = __stringify(field), .mode = 0444, \
489 .owner = THIS_MODULE }, \
490 .show = show_modinfo_##field, \
491 .setup = setup_modinfo_##field, \
492 .test = modinfo_##field##_exists, \
493 .free = free_modinfo_##field, \
496 MODINFO_ATTR(version);
497 MODINFO_ATTR(srcversion);
499 #ifdef CONFIG_MODULE_UNLOAD
500 /* Init the unload section of the module. */
501 static void module_unload_init(struct module *mod)
505 INIT_LIST_HEAD(&mod->modules_which_use_me);
506 for (i = 0; i < NR_CPUS; i++)
507 local_set(&mod->ref[i].count, 0);
508 /* Hold reference count during initialization. */
509 local_set(&mod->ref[raw_smp_processor_id()].count, 1);
510 /* Backwards compatibility macros put refcount during init. */
511 mod->waiter = current;
514 /* modules using other modules */
517 struct list_head list;
518 struct module *module_which_uses;
521 /* Does a already use b? */
522 static int already_uses(struct module *a, struct module *b)
524 struct module_use *use;
526 list_for_each_entry(use, &b->modules_which_use_me, list) {
527 if (use->module_which_uses == a) {
528 DEBUGP("%s uses %s!\n", a->name, b->name);
532 DEBUGP("%s does not use %s!\n", a->name, b->name);
536 /* Module a uses b */
537 static int use_module(struct module *a, struct module *b)
539 struct module_use *use;
542 if (b == NULL || already_uses(a, b)) return 1;
544 if (!strong_try_module_get(b))
547 DEBUGP("Allocating new usage for %s.\n", a->name);
548 use = kmalloc(sizeof(*use), GFP_ATOMIC);
550 printk("%s: out of memory loading\n", a->name);
555 use->module_which_uses = a;
556 list_add(&use->list, &b->modules_which_use_me);
557 no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
561 /* Clear the unload stuff of the module. */
562 static void module_unload_free(struct module *mod)
566 list_for_each_entry(i, &modules, list) {
567 struct module_use *use;
569 list_for_each_entry(use, &i->modules_which_use_me, list) {
570 if (use->module_which_uses == mod) {
571 DEBUGP("%s unusing %s\n", mod->name, i->name);
573 list_del(&use->list);
575 sysfs_remove_link(i->holders_dir, mod->name);
576 /* There can be at most one match. */
583 #ifdef CONFIG_MODULE_FORCE_UNLOAD
584 static inline int try_force_unload(unsigned int flags)
586 int ret = (flags & O_TRUNC);
588 add_taint(TAINT_FORCED_RMMOD);
592 static inline int try_force_unload(unsigned int flags)
596 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
605 /* Whole machine is stopped with interrupts off when this runs. */
606 static int __try_stop_module(void *_sref)
608 struct stopref *sref = _sref;
610 /* If it's not unused, quit unless we are told to block. */
611 if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
612 if (!(*sref->forced = try_force_unload(sref->flags)))
616 /* Mark it as dying. */
617 sref->mod->state = MODULE_STATE_GOING;
621 static int try_stop_module(struct module *mod, int flags, int *forced)
623 struct stopref sref = { mod, flags, forced };
625 return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
628 unsigned int module_refcount(struct module *mod)
630 unsigned int i, total = 0;
632 for (i = 0; i < NR_CPUS; i++)
633 total += local_read(&mod->ref[i].count);
636 EXPORT_SYMBOL(module_refcount);
638 /* This exists whether we can unload or not */
639 static void free_module(struct module *mod);
641 static void wait_for_zero_refcount(struct module *mod)
643 /* Since we might sleep for some time, drop the semaphore first */
644 mutex_unlock(&module_mutex);
646 DEBUGP("Looking at refcount...\n");
647 set_current_state(TASK_UNINTERRUPTIBLE);
648 if (module_refcount(mod) == 0)
652 current->state = TASK_RUNNING;
653 mutex_lock(&module_mutex);
656 int delete_module(const char *name, unsigned int flags)
661 if (mutex_lock_interruptible(&module_mutex) != 0)
664 mod = find_module(name);
670 if (!list_empty(&mod->modules_which_use_me)) {
671 /* Other modules depend on us: get rid of them first. */
676 /* Doing init or already dying? */
677 if (mod->state != MODULE_STATE_LIVE) {
678 /* FIXME: if (force), slam module count and wake up
680 DEBUGP("%s already dying\n", mod->name);
685 /* If it has an init func, it must have an exit func to unload */
686 if ((mod->init != NULL && mod->exit == NULL)
688 forced = try_force_unload(flags);
690 /* This module can't be removed */
696 /* Set this up before setting mod->state */
697 mod->waiter = current;
699 /* Stop the machine so refcounts can't move and disable module. */
700 ret = try_stop_module(mod, flags, &forced);
704 /* Never wait if forced. */
705 if (!forced && module_refcount(mod) != 0)
706 wait_for_zero_refcount(mod);
708 /* Final destruction now noone is using it. */
709 if (mod->exit != NULL) {
710 mutex_unlock(&module_mutex);
712 mutex_lock(&module_mutex);
717 mutex_unlock(&module_mutex);
722 sys_delete_module(const char __user *name_user, unsigned int flags)
724 char name[MODULE_NAME_LEN];
726 if (!capable(CAP_SYS_MODULE))
729 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
731 name[MODULE_NAME_LEN-1] = '\0';
733 return delete_module(name, flags);
736 static void print_unload_info(struct seq_file *m, struct module *mod)
738 struct module_use *use;
739 int printed_something = 0;
741 seq_printf(m, " %u ", module_refcount(mod));
743 /* Always include a trailing , so userspace can differentiate
744 between this and the old multi-field proc format. */
745 list_for_each_entry(use, &mod->modules_which_use_me, list) {
746 printed_something = 1;
747 seq_printf(m, "%s,", use->module_which_uses->name);
751 printed_something = 1;
752 seq_printf(m, "[unsafe],");
755 if (mod->init != NULL && mod->exit == NULL) {
756 printed_something = 1;
757 seq_printf(m, "[permanent],");
760 if (!printed_something)
764 void __symbol_put(const char *symbol)
766 struct module *owner;
768 const unsigned long *crc;
770 spin_lock_irqsave(&modlist_lock, flags);
771 if (!__find_symbol(symbol, &owner, &crc, 1))
774 spin_unlock_irqrestore(&modlist_lock, flags);
776 EXPORT_SYMBOL(__symbol_put);
778 void symbol_put_addr(void *addr)
780 struct module *modaddr;
782 if (core_kernel_text((unsigned long)addr))
785 if (!(modaddr = module_text_address((unsigned long)addr)))
789 EXPORT_SYMBOL_GPL(symbol_put_addr);
791 static ssize_t show_refcnt(struct module_attribute *mattr,
792 struct module *mod, char *buffer)
794 /* sysfs holds a reference */
795 return sprintf(buffer, "%u\n", module_refcount(mod)-1);
798 static struct module_attribute refcnt = {
799 .attr = { .name = "refcnt", .mode = 0444, .owner = THIS_MODULE },
803 void module_put(struct module *module)
806 unsigned int cpu = get_cpu();
807 local_dec(&module->ref[cpu].count);
808 /* Maybe they're waiting for us to drop reference? */
809 if (unlikely(!module_is_live(module)))
810 wake_up_process(module->waiter);
814 EXPORT_SYMBOL(module_put);
816 #else /* !CONFIG_MODULE_UNLOAD */
817 static void print_unload_info(struct seq_file *m, struct module *mod)
819 /* We don't know the usage count, or what modules are using. */
820 seq_printf(m, " - -");
823 static inline void module_unload_free(struct module *mod)
827 static inline int use_module(struct module *a, struct module *b)
829 return strong_try_module_get(b);
832 static inline void module_unload_init(struct module *mod)
835 #endif /* CONFIG_MODULE_UNLOAD */
837 static ssize_t show_initstate(struct module_attribute *mattr,
838 struct module *mod, char *buffer)
840 const char *state = "unknown";
842 switch (mod->state) {
843 case MODULE_STATE_LIVE:
846 case MODULE_STATE_COMING:
849 case MODULE_STATE_GOING:
853 return sprintf(buffer, "%s\n", state);
856 static struct module_attribute initstate = {
857 .attr = { .name = "initstate", .mode = 0444, .owner = THIS_MODULE },
858 .show = show_initstate,
861 static struct module_attribute *modinfo_attrs[] = {
865 #ifdef CONFIG_MODULE_UNLOAD
871 static const char vermagic[] = VERMAGIC_STRING;
873 #ifdef CONFIG_MODVERSIONS
874 static int check_version(Elf_Shdr *sechdrs,
875 unsigned int versindex,
878 const unsigned long *crc)
880 unsigned int i, num_versions;
881 struct modversion_info *versions;
883 /* Exporting module didn't supply crcs? OK, we're already tainted. */
887 versions = (void *) sechdrs[versindex].sh_addr;
888 num_versions = sechdrs[versindex].sh_size
889 / sizeof(struct modversion_info);
891 for (i = 0; i < num_versions; i++) {
892 if (strcmp(versions[i].name, symname) != 0)
895 if (versions[i].crc == *crc)
897 printk("%s: disagrees about version of symbol %s\n",
899 DEBUGP("Found checksum %lX vs module %lX\n",
900 *crc, versions[i].crc);
903 /* Not in module's version table. OK, but that taints the kernel. */
904 if (!(tainted & TAINT_FORCED_MODULE))
905 printk("%s: no version for \"%s\" found: kernel tainted.\n",
907 add_taint_module(mod, TAINT_FORCED_MODULE);
911 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
912 unsigned int versindex,
915 const unsigned long *crc;
916 struct module *owner;
918 if (!__find_symbol("struct_module", &owner, &crc, 1))
920 return check_version(sechdrs, versindex, "struct_module", mod,
924 /* First part is kernel version, which we ignore. */
925 static inline int same_magic(const char *amagic, const char *bmagic)
927 amagic += strcspn(amagic, " ");
928 bmagic += strcspn(bmagic, " ");
929 return strcmp(amagic, bmagic) == 0;
932 static inline int check_version(Elf_Shdr *sechdrs,
933 unsigned int versindex,
936 const unsigned long *crc)
941 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
942 unsigned int versindex,
948 static inline int same_magic(const char *amagic, const char *bmagic)
950 return strcmp(amagic, bmagic) == 0;
952 #endif /* CONFIG_MODVERSIONS */
954 /* Resolve a symbol for this module. I.e. if we find one, record usage.
955 Must be holding module_mutex. */
956 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
957 unsigned int versindex,
961 struct module *owner;
963 const unsigned long *crc;
965 ret = __find_symbol(name, &owner, &crc,
966 !(mod->taints & TAINT_PROPRIETARY_MODULE));
968 /* use_module can fail due to OOM, or module unloading */
969 if (!check_version(sechdrs, versindex, name, mod, crc) ||
970 !use_module(mod, owner))
978 * /sys/module/foo/sections stuff
979 * J. Corbet <corbet@lwn.net>
981 #ifdef CONFIG_KALLSYMS
982 static ssize_t module_sect_show(struct module_attribute *mattr,
983 struct module *mod, char *buf)
985 struct module_sect_attr *sattr =
986 container_of(mattr, struct module_sect_attr, mattr);
987 return sprintf(buf, "0x%lx\n", sattr->address);
990 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
994 for (section = 0; section < sect_attrs->nsections; section++)
995 kfree(sect_attrs->attrs[section].name);
999 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1000 char *secstrings, Elf_Shdr *sechdrs)
1002 unsigned int nloaded = 0, i, size[2];
1003 struct module_sect_attrs *sect_attrs;
1004 struct module_sect_attr *sattr;
1005 struct attribute **gattr;
1007 /* Count loaded sections and allocate structures */
1008 for (i = 0; i < nsect; i++)
1009 if (sechdrs[i].sh_flags & SHF_ALLOC)
1011 size[0] = ALIGN(sizeof(*sect_attrs)
1012 + nloaded * sizeof(sect_attrs->attrs[0]),
1013 sizeof(sect_attrs->grp.attrs[0]));
1014 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1015 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1016 if (sect_attrs == NULL)
1019 /* Setup section attributes. */
1020 sect_attrs->grp.name = "sections";
1021 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1023 sect_attrs->nsections = 0;
1024 sattr = §_attrs->attrs[0];
1025 gattr = §_attrs->grp.attrs[0];
1026 for (i = 0; i < nsect; i++) {
1027 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1029 sattr->address = sechdrs[i].sh_addr;
1030 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1032 if (sattr->name == NULL)
1034 sect_attrs->nsections++;
1035 sattr->mattr.show = module_sect_show;
1036 sattr->mattr.store = NULL;
1037 sattr->mattr.attr.name = sattr->name;
1038 sattr->mattr.attr.owner = mod;
1039 sattr->mattr.attr.mode = S_IRUGO;
1040 *(gattr++) = &(sattr++)->mattr.attr;
1044 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1047 mod->sect_attrs = sect_attrs;
1050 free_sect_attrs(sect_attrs);
1053 static void remove_sect_attrs(struct module *mod)
1055 if (mod->sect_attrs) {
1056 sysfs_remove_group(&mod->mkobj.kobj,
1057 &mod->sect_attrs->grp);
1058 /* We are positive that no one is using any sect attrs
1059 * at this point. Deallocate immediately. */
1060 free_sect_attrs(mod->sect_attrs);
1061 mod->sect_attrs = NULL;
1067 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1068 char *sectstrings, Elf_Shdr *sechdrs)
1072 static inline void remove_sect_attrs(struct module *mod)
1075 #endif /* CONFIG_KALLSYMS */
1078 int module_add_modinfo_attrs(struct module *mod)
1080 struct module_attribute *attr;
1081 struct module_attribute *temp_attr;
1085 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1086 (ARRAY_SIZE(modinfo_attrs) + 1)),
1088 if (!mod->modinfo_attrs)
1091 temp_attr = mod->modinfo_attrs;
1092 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1094 (attr->test && attr->test(mod))) {
1095 memcpy(temp_attr, attr, sizeof(*temp_attr));
1096 temp_attr->attr.owner = mod;
1097 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1104 void module_remove_modinfo_attrs(struct module *mod)
1106 struct module_attribute *attr;
1109 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1110 /* pick a field to test for end of list */
1111 if (!attr->attr.name)
1113 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1117 kfree(mod->modinfo_attrs);
1122 int mod_sysfs_init(struct module *mod)
1126 if (!module_subsys.kset.subsys) {
1127 printk(KERN_ERR "%s: module_subsys not initialized\n",
1132 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1133 err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name);
1136 kobj_set_kset_s(&mod->mkobj, module_subsys);
1137 mod->mkobj.mod = mod;
1139 kobject_init(&mod->mkobj.kobj);
1145 int mod_sysfs_setup(struct module *mod,
1146 struct kernel_param *kparam,
1147 unsigned int num_params)
1151 /* delay uevent until full sysfs population */
1152 err = kobject_add(&mod->mkobj.kobj);
1156 mod->holders_dir = kobject_add_dir(&mod->mkobj.kobj, "holders");
1157 if (!mod->holders_dir)
1160 err = module_param_sysfs_setup(mod, kparam, num_params);
1162 goto out_unreg_holders;
1164 err = module_add_modinfo_attrs(mod);
1166 goto out_unreg_param;
1168 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1172 module_param_sysfs_remove(mod);
1174 kobject_unregister(mod->holders_dir);
1176 kobject_del(&mod->mkobj.kobj);
1177 kobject_put(&mod->mkobj.kobj);
1183 static void mod_kobject_remove(struct module *mod)
1185 module_remove_modinfo_attrs(mod);
1186 module_param_sysfs_remove(mod);
1187 kobject_unregister(mod->mkobj.drivers_dir);
1188 kobject_unregister(mod->holders_dir);
1189 kobject_unregister(&mod->mkobj.kobj);
1193 * unlink the module with the whole machine is stopped with interrupts off
1194 * - this defends against kallsyms not taking locks
1196 static int __unlink_module(void *_mod)
1198 struct module *mod = _mod;
1199 list_del(&mod->list);
1203 /* Free a module, remove from lists, etc (must hold module mutex). */
1204 static void free_module(struct module *mod)
1206 /* Delete from various lists */
1207 stop_machine_run(__unlink_module, mod, NR_CPUS);
1208 remove_sect_attrs(mod);
1209 mod_kobject_remove(mod);
1211 unwind_remove_table(mod->unwind_info, 0);
1213 /* Arch-specific cleanup. */
1214 module_arch_cleanup(mod);
1216 /* Module unload stuff */
1217 module_unload_free(mod);
1219 /* This may be NULL, but that's OK */
1220 module_free(mod, mod->module_init);
1223 percpu_modfree(mod->percpu);
1225 /* Free lock-classes: */
1226 lockdep_free_key_range(mod->module_core, mod->core_size);
1228 /* Finally, free the core (containing the module structure) */
1229 module_free(mod, mod->module_core);
1232 void *__symbol_get(const char *symbol)
1234 struct module *owner;
1235 unsigned long value, flags;
1236 const unsigned long *crc;
1238 spin_lock_irqsave(&modlist_lock, flags);
1239 value = __find_symbol(symbol, &owner, &crc, 1);
1240 if (value && !strong_try_module_get(owner))
1242 spin_unlock_irqrestore(&modlist_lock, flags);
1244 return (void *)value;
1246 EXPORT_SYMBOL_GPL(__symbol_get);
1249 * Ensure that an exported symbol [global namespace] does not already exist
1250 * in the Kernel or in some other modules exported symbol table.
1252 static int verify_export_symbols(struct module *mod)
1254 const char *name = NULL;
1255 unsigned long i, ret = 0;
1256 struct module *owner;
1257 const unsigned long *crc;
1259 for (i = 0; i < mod->num_syms; i++)
1260 if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) {
1261 name = mod->syms[i].name;
1266 for (i = 0; i < mod->num_gpl_syms; i++)
1267 if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) {
1268 name = mod->gpl_syms[i].name;
1275 printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
1276 mod->name, name, module_name(owner));
1281 /* Change all symbols so that sh_value encodes the pointer directly. */
1282 static int simplify_symbols(Elf_Shdr *sechdrs,
1283 unsigned int symindex,
1285 unsigned int versindex,
1286 unsigned int pcpuindex,
1289 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1290 unsigned long secbase;
1291 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1294 for (i = 1; i < n; i++) {
1295 switch (sym[i].st_shndx) {
1297 /* We compiled with -fno-common. These are not
1298 supposed to happen. */
1299 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1300 printk("%s: please compile with -fno-common\n",
1306 /* Don't need to do anything */
1307 DEBUGP("Absolute symbol: 0x%08lx\n",
1308 (long)sym[i].st_value);
1313 = resolve_symbol(sechdrs, versindex,
1314 strtab + sym[i].st_name, mod);
1316 /* Ok if resolved. */
1317 if (sym[i].st_value != 0)
1320 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1323 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1324 mod->name, strtab + sym[i].st_name);
1329 /* Divert to percpu allocation if a percpu var. */
1330 if (sym[i].st_shndx == pcpuindex)
1331 secbase = (unsigned long)mod->percpu;
1333 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1334 sym[i].st_value += secbase;
1342 /* Update size with this section: return offset. */
1343 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
1347 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1348 *size = ret + sechdr->sh_size;
1352 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1353 might -- code, read-only data, read-write data, small data. Tally
1354 sizes, and place the offsets into sh_entsize fields: high bit means it
1356 static void layout_sections(struct module *mod,
1357 const Elf_Ehdr *hdr,
1359 const char *secstrings)
1361 static unsigned long const masks[][2] = {
1362 /* NOTE: all executable code must be the first section
1363 * in this array; otherwise modify the text_size
1364 * finder in the two loops below */
1365 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1366 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1367 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1368 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1372 for (i = 0; i < hdr->e_shnum; i++)
1373 sechdrs[i].sh_entsize = ~0UL;
1375 DEBUGP("Core section allocation order:\n");
1376 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1377 for (i = 0; i < hdr->e_shnum; ++i) {
1378 Elf_Shdr *s = &sechdrs[i];
1380 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1381 || (s->sh_flags & masks[m][1])
1382 || s->sh_entsize != ~0UL
1383 || strncmp(secstrings + s->sh_name,
1386 s->sh_entsize = get_offset(&mod->core_size, s);
1387 DEBUGP("\t%s\n", secstrings + s->sh_name);
1390 mod->core_text_size = mod->core_size;
1393 DEBUGP("Init section allocation order:\n");
1394 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1395 for (i = 0; i < hdr->e_shnum; ++i) {
1396 Elf_Shdr *s = &sechdrs[i];
1398 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1399 || (s->sh_flags & masks[m][1])
1400 || s->sh_entsize != ~0UL
1401 || strncmp(secstrings + s->sh_name,
1404 s->sh_entsize = (get_offset(&mod->init_size, s)
1405 | INIT_OFFSET_MASK);
1406 DEBUGP("\t%s\n", secstrings + s->sh_name);
1409 mod->init_text_size = mod->init_size;
1413 static void set_license(struct module *mod, const char *license)
1416 license = "unspecified";
1418 if (!license_is_gpl_compatible(license)) {
1419 if (!(tainted & TAINT_PROPRIETARY_MODULE))
1420 printk(KERN_WARNING "%s: module license '%s' taints "
1421 "kernel.\n", mod->name, license);
1422 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1426 /* Parse tag=value strings from .modinfo section */
1427 static char *next_string(char *string, unsigned long *secsize)
1429 /* Skip non-zero chars */
1432 if ((*secsize)-- <= 1)
1436 /* Skip any zero padding. */
1437 while (!string[0]) {
1439 if ((*secsize)-- <= 1)
1445 static char *get_modinfo(Elf_Shdr *sechdrs,
1450 unsigned int taglen = strlen(tag);
1451 unsigned long size = sechdrs[info].sh_size;
1453 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1454 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1455 return p + taglen + 1;
1460 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1461 unsigned int infoindex)
1463 struct module_attribute *attr;
1466 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1469 get_modinfo(sechdrs,
1475 #ifdef CONFIG_KALLSYMS
1476 int is_exported(const char *name, const struct module *mod)
1478 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1481 if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1488 static char elf_type(const Elf_Sym *sym,
1490 const char *secstrings,
1493 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1494 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1499 if (sym->st_shndx == SHN_UNDEF)
1501 if (sym->st_shndx == SHN_ABS)
1503 if (sym->st_shndx >= SHN_LORESERVE)
1505 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1507 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1508 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1509 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1511 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1516 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1517 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1522 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1523 ".debug", strlen(".debug")) == 0)
1528 static void add_kallsyms(struct module *mod,
1530 unsigned int symindex,
1531 unsigned int strindex,
1532 const char *secstrings)
1536 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1537 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1538 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1540 /* Set types up while we still have access to sections. */
1541 for (i = 0; i < mod->num_symtab; i++)
1542 mod->symtab[i].st_info
1543 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1546 static inline void add_kallsyms(struct module *mod,
1548 unsigned int symindex,
1549 unsigned int strindex,
1550 const char *secstrings)
1553 #endif /* CONFIG_KALLSYMS */
1555 /* Allocate and load the module: note that size of section 0 is always
1556 zero, and we rely on this for optional sections. */
1557 static struct module *load_module(void __user *umod,
1559 const char __user *uargs)
1563 char *secstrings, *args, *modmagic, *strtab = NULL;
1565 unsigned int symindex = 0;
1566 unsigned int strindex = 0;
1567 unsigned int setupindex;
1568 unsigned int exindex;
1569 unsigned int exportindex;
1570 unsigned int modindex;
1571 unsigned int obsparmindex;
1572 unsigned int infoindex;
1573 unsigned int gplindex;
1574 unsigned int crcindex;
1575 unsigned int gplcrcindex;
1576 unsigned int versindex;
1577 unsigned int pcpuindex;
1578 unsigned int gplfutureindex;
1579 unsigned int gplfuturecrcindex;
1580 unsigned int unwindex = 0;
1581 unsigned int unusedindex;
1582 unsigned int unusedcrcindex;
1583 unsigned int unusedgplindex;
1584 unsigned int unusedgplcrcindex;
1587 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1588 struct exception_table_entry *extable;
1589 mm_segment_t old_fs;
1591 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1593 if (len < sizeof(*hdr))
1594 return ERR_PTR(-ENOEXEC);
1596 /* Suck in entire file: we'll want most of it. */
1597 /* vmalloc barfs on "unusual" numbers. Check here */
1598 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1599 return ERR_PTR(-ENOMEM);
1600 if (copy_from_user(hdr, umod, len) != 0) {
1605 /* Sanity checks against insmoding binaries or wrong arch,
1606 weird elf version */
1607 if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
1608 || hdr->e_type != ET_REL
1609 || !elf_check_arch(hdr)
1610 || hdr->e_shentsize != sizeof(*sechdrs)) {
1615 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1618 /* Convenience variables */
1619 sechdrs = (void *)hdr + hdr->e_shoff;
1620 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1621 sechdrs[0].sh_addr = 0;
1623 for (i = 1; i < hdr->e_shnum; i++) {
1624 if (sechdrs[i].sh_type != SHT_NOBITS
1625 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1628 /* Mark all sections sh_addr with their address in the
1630 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1632 /* Internal symbols and strings. */
1633 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1635 strindex = sechdrs[i].sh_link;
1636 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1638 #ifndef CONFIG_MODULE_UNLOAD
1639 /* Don't load .exit sections */
1640 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1641 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1645 modindex = find_sec(hdr, sechdrs, secstrings,
1646 ".gnu.linkonce.this_module");
1648 printk(KERN_WARNING "No module found in object\n");
1652 mod = (void *)sechdrs[modindex].sh_addr;
1654 if (symindex == 0) {
1655 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1661 /* Optional sections */
1662 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1663 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1664 gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1665 unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
1666 unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
1667 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1668 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1669 gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1670 unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
1671 unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
1672 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1673 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1674 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1675 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1676 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1677 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1678 #ifdef ARCH_UNWIND_SECTION_NAME
1679 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1682 /* Don't keep modinfo section */
1683 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1684 #ifdef CONFIG_KALLSYMS
1685 /* Keep symbol and string tables for decoding later. */
1686 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1687 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1690 sechdrs[unwindex].sh_flags |= SHF_ALLOC;
1692 /* Check module struct version now, before we try to use module. */
1693 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1698 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1699 /* This is allowed: modprobe --force will invalidate it. */
1701 add_taint_module(mod, TAINT_FORCED_MODULE);
1702 printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
1704 } else if (!same_magic(modmagic, vermagic)) {
1705 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1706 mod->name, modmagic, vermagic);
1711 /* Now copy in args */
1712 args = strndup_user(uargs, ~0UL >> 1);
1714 err = PTR_ERR(args);
1718 if (find_module(mod->name)) {
1723 mod->state = MODULE_STATE_COMING;
1725 /* Allow arches to frob section contents and sizes. */
1726 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1731 /* We have a special allocation for this section. */
1732 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1733 sechdrs[pcpuindex].sh_addralign,
1739 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1740 mod->percpu = percpu;
1743 /* Determine total sizes, and put offsets in sh_entsize. For now
1744 this is done generically; there doesn't appear to be any
1745 special cases for the architectures. */
1746 layout_sections(mod, hdr, sechdrs, secstrings);
1748 /* Do the allocs. */
1749 ptr = module_alloc(mod->core_size);
1754 memset(ptr, 0, mod->core_size);
1755 mod->module_core = ptr;
1757 ptr = module_alloc(mod->init_size);
1758 if (!ptr && mod->init_size) {
1762 memset(ptr, 0, mod->init_size);
1763 mod->module_init = ptr;
1765 /* Transfer each section which specifies SHF_ALLOC */
1766 DEBUGP("final section addresses:\n");
1767 for (i = 0; i < hdr->e_shnum; i++) {
1770 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1773 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
1774 dest = mod->module_init
1775 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
1777 dest = mod->module_core + sechdrs[i].sh_entsize;
1779 if (sechdrs[i].sh_type != SHT_NOBITS)
1780 memcpy(dest, (void *)sechdrs[i].sh_addr,
1781 sechdrs[i].sh_size);
1782 /* Update sh_addr to point to copy in image. */
1783 sechdrs[i].sh_addr = (unsigned long)dest;
1784 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
1786 /* Module has been moved. */
1787 mod = (void *)sechdrs[modindex].sh_addr;
1789 /* Now we've moved module, initialize linked lists, etc. */
1790 module_unload_init(mod);
1792 /* Initialize kobject, so we can reference it. */
1793 if (mod_sysfs_init(mod) != 0)
1796 /* Set up license info based on the info section */
1797 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
1799 if (strcmp(mod->name, "ndiswrapper") == 0)
1800 add_taint(TAINT_PROPRIETARY_MODULE);
1801 if (strcmp(mod->name, "driverloader") == 0)
1802 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1804 /* Set up MODINFO_ATTR fields */
1805 setup_modinfo(mod, sechdrs, infoindex);
1807 /* Fix up syms, so that st_value is a pointer to location. */
1808 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
1813 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
1814 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
1815 mod->syms = (void *)sechdrs[exportindex].sh_addr;
1817 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
1818 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
1819 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
1821 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
1822 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
1823 sizeof(*mod->gpl_future_syms);
1824 mod->num_unused_syms = sechdrs[unusedindex].sh_size /
1825 sizeof(*mod->unused_syms);
1826 mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
1827 sizeof(*mod->unused_gpl_syms);
1828 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
1829 if (gplfuturecrcindex)
1830 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
1832 mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
1834 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
1835 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
1836 if (unusedgplcrcindex)
1837 mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr;
1839 #ifdef CONFIG_MODVERSIONS
1840 if ((mod->num_syms && !crcindex) ||
1841 (mod->num_gpl_syms && !gplcrcindex) ||
1842 (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
1843 (mod->num_unused_syms && !unusedcrcindex) ||
1844 (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
1845 printk(KERN_WARNING "%s: No versions for exported symbols."
1846 " Tainting kernel.\n", mod->name);
1847 add_taint_module(mod, TAINT_FORCED_MODULE);
1851 /* Now do relocations. */
1852 for (i = 1; i < hdr->e_shnum; i++) {
1853 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1854 unsigned int info = sechdrs[i].sh_info;
1856 /* Not a valid relocation section? */
1857 if (info >= hdr->e_shnum)
1860 /* Don't bother with non-allocated sections */
1861 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1864 if (sechdrs[i].sh_type == SHT_REL)
1865 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
1866 else if (sechdrs[i].sh_type == SHT_RELA)
1867 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1873 /* Find duplicate symbols */
1874 err = verify_export_symbols(mod);
1879 /* Set up and sort exception table */
1880 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
1881 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
1882 sort_extable(extable, extable + mod->num_exentries);
1884 /* Finally, copy percpu area over. */
1885 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
1886 sechdrs[pcpuindex].sh_size);
1888 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
1890 err = module_finalize(hdr, sechdrs, mod);
1894 /* flush the icache in correct context */
1899 * Flush the instruction cache, since we've played with text.
1900 * Do it before processing of module parameters, so the module
1901 * can provide parameter accessor functions of its own.
1903 if (mod->module_init)
1904 flush_icache_range((unsigned long)mod->module_init,
1905 (unsigned long)mod->module_init
1907 flush_icache_range((unsigned long)mod->module_core,
1908 (unsigned long)mod->module_core + mod->core_size);
1914 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
1917 /* Size of section 0 is 0, so this works well if no params */
1918 err = parse_args(mod->name, mod->args,
1919 (struct kernel_param *)
1920 sechdrs[setupindex].sh_addr,
1921 sechdrs[setupindex].sh_size
1922 / sizeof(struct kernel_param),
1927 err = mod_sysfs_setup(mod,
1928 (struct kernel_param *)
1929 sechdrs[setupindex].sh_addr,
1930 sechdrs[setupindex].sh_size
1931 / sizeof(struct kernel_param));
1934 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
1936 /* Size of section 0 is 0, so this works well if no unwind info. */
1937 mod->unwind_info = unwind_add_table(mod,
1938 (void *)sechdrs[unwindex].sh_addr,
1939 sechdrs[unwindex].sh_size);
1941 /* Get rid of temporary copy */
1948 module_arch_cleanup(mod);
1950 module_unload_free(mod);
1951 module_free(mod, mod->module_init);
1953 module_free(mod, mod->module_core);
1956 percpu_modfree(percpu);
1961 return ERR_PTR(err);
1964 printk(KERN_ERR "Module len %lu truncated\n", len);
1970 * link the module with the whole machine is stopped with interrupts off
1971 * - this defends against kallsyms not taking locks
1973 static int __link_module(void *_mod)
1975 struct module *mod = _mod;
1976 list_add(&mod->list, &modules);
1980 /* This is where the real work happens */
1982 sys_init_module(void __user *umod,
1984 const char __user *uargs)
1989 /* Must have permission */
1990 if (!capable(CAP_SYS_MODULE))
1993 /* Only one module load at a time, please */
1994 if (mutex_lock_interruptible(&module_mutex) != 0)
1997 /* Do all the hard work */
1998 mod = load_module(umod, len, uargs);
2000 mutex_unlock(&module_mutex);
2001 return PTR_ERR(mod);
2004 /* Now sew it into the lists. They won't access us, since
2005 strong_try_module_get() will fail. */
2006 stop_machine_run(__link_module, mod, NR_CPUS);
2008 /* Drop lock so they can recurse */
2009 mutex_unlock(&module_mutex);
2011 blocking_notifier_call_chain(&module_notify_list,
2012 MODULE_STATE_COMING, mod);
2014 /* Start the module */
2015 if (mod->init != NULL)
2018 /* Init routine failed: abort. Try to protect us from
2019 buggy refcounters. */
2020 mod->state = MODULE_STATE_GOING;
2021 synchronize_sched();
2023 printk(KERN_ERR "%s: module is now stuck!\n",
2027 mutex_lock(&module_mutex);
2029 mutex_unlock(&module_mutex);
2034 /* Now it's a first class citizen! */
2035 mutex_lock(&module_mutex);
2036 mod->state = MODULE_STATE_LIVE;
2037 /* Drop initial reference. */
2039 unwind_remove_table(mod->unwind_info, 1);
2040 module_free(mod, mod->module_init);
2041 mod->module_init = NULL;
2043 mod->init_text_size = 0;
2044 mutex_unlock(&module_mutex);
2049 static inline int within(unsigned long addr, void *start, unsigned long size)
2051 return ((void *)addr >= start && (void *)addr < start + size);
2054 #ifdef CONFIG_KALLSYMS
2056 * This ignores the intensely annoying "mapping symbols" found
2057 * in ARM ELF files: $a, $t and $d.
2059 static inline int is_arm_mapping_symbol(const char *str)
2061 return str[0] == '$' && strchr("atd", str[1])
2062 && (str[2] == '\0' || str[2] == '.');
2065 static const char *get_ksymbol(struct module *mod,
2067 unsigned long *size,
2068 unsigned long *offset)
2070 unsigned int i, best = 0;
2071 unsigned long nextval;
2073 /* At worse, next value is at end of module */
2074 if (within(addr, mod->module_init, mod->init_size))
2075 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2077 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2079 /* Scan for closest preceeding symbol, and next symbol. (ELF
2080 starts real symbols at 1). */
2081 for (i = 1; i < mod->num_symtab; i++) {
2082 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2085 /* We ignore unnamed symbols: they're uninformative
2086 * and inserted at a whim. */
2087 if (mod->symtab[i].st_value <= addr
2088 && mod->symtab[i].st_value > mod->symtab[best].st_value
2089 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2090 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2092 if (mod->symtab[i].st_value > addr
2093 && mod->symtab[i].st_value < nextval
2094 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2095 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2096 nextval = mod->symtab[i].st_value;
2102 *size = nextval - mod->symtab[best].st_value;
2103 *offset = addr - mod->symtab[best].st_value;
2104 return mod->strtab + mod->symtab[best].st_name;
2107 /* For kallsyms to ask for address resolution. NULL means not found.
2108 We don't lock, as this is used for oops resolution and races are a
2110 const char *module_address_lookup(unsigned long addr,
2111 unsigned long *size,
2112 unsigned long *offset,
2117 list_for_each_entry(mod, &modules, list) {
2118 if (within(addr, mod->module_init, mod->init_size)
2119 || within(addr, mod->module_core, mod->core_size)) {
2121 *modname = mod->name;
2122 return get_ksymbol(mod, addr, size, offset);
2128 struct module *module_get_kallsym(unsigned int symnum, unsigned long *value,
2129 char *type, char *name, size_t namelen)
2133 mutex_lock(&module_mutex);
2134 list_for_each_entry(mod, &modules, list) {
2135 if (symnum < mod->num_symtab) {
2136 *value = mod->symtab[symnum].st_value;
2137 *type = mod->symtab[symnum].st_info;
2138 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2140 mutex_unlock(&module_mutex);
2143 symnum -= mod->num_symtab;
2145 mutex_unlock(&module_mutex);
2149 static unsigned long mod_find_symname(struct module *mod, const char *name)
2153 for (i = 0; i < mod->num_symtab; i++)
2154 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2155 mod->symtab[i].st_info != 'U')
2156 return mod->symtab[i].st_value;
2160 /* Look for this name: can be of form module:name. */
2161 unsigned long module_kallsyms_lookup_name(const char *name)
2165 unsigned long ret = 0;
2167 /* Don't lock: we're in enough trouble already. */
2168 if ((colon = strchr(name, ':')) != NULL) {
2170 if ((mod = find_module(name)) != NULL)
2171 ret = mod_find_symname(mod, colon+1);
2174 list_for_each_entry(mod, &modules, list)
2175 if ((ret = mod_find_symname(mod, name)) != 0)
2180 #endif /* CONFIG_KALLSYMS */
2182 /* Called by the /proc file system to return a list of modules. */
2183 static void *m_start(struct seq_file *m, loff_t *pos)
2185 struct list_head *i;
2188 mutex_lock(&module_mutex);
2189 list_for_each(i, &modules) {
2198 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2200 struct list_head *i = p;
2202 if (i->next == &modules)
2207 static void m_stop(struct seq_file *m, void *p)
2209 mutex_unlock(&module_mutex);
2212 static char *taint_flags(unsigned int taints, char *buf)
2218 if (taints & TAINT_PROPRIETARY_MODULE)
2220 if (taints & TAINT_FORCED_MODULE)
2223 * TAINT_FORCED_RMMOD: could be added.
2224 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2234 static int m_show(struct seq_file *m, void *p)
2236 struct module *mod = list_entry(p, struct module, list);
2239 seq_printf(m, "%s %lu",
2240 mod->name, mod->init_size + mod->core_size);
2241 print_unload_info(m, mod);
2243 /* Informative for users. */
2244 seq_printf(m, " %s",
2245 mod->state == MODULE_STATE_GOING ? "Unloading":
2246 mod->state == MODULE_STATE_COMING ? "Loading":
2248 /* Used by oprofile and other similar tools. */
2249 seq_printf(m, " 0x%p", mod->module_core);
2253 seq_printf(m, " %s", taint_flags(mod->taints, buf));
2255 seq_printf(m, "\n");
2259 /* Format: modulename size refcount deps address
2261 Where refcount is a number or -, and deps is a comma-separated list
2264 const struct seq_operations modules_op = {
2271 /* Given an address, look for it in the module exception tables. */
2272 const struct exception_table_entry *search_module_extables(unsigned long addr)
2274 unsigned long flags;
2275 const struct exception_table_entry *e = NULL;
2278 spin_lock_irqsave(&modlist_lock, flags);
2279 list_for_each_entry(mod, &modules, list) {
2280 if (mod->num_exentries == 0)
2283 e = search_extable(mod->extable,
2284 mod->extable + mod->num_exentries - 1,
2289 spin_unlock_irqrestore(&modlist_lock, flags);
2291 /* Now, if we found one, we are running inside it now, hence
2292 we cannot unload the module, hence no refcnt needed. */
2297 * Is this a valid module address?
2299 int is_module_address(unsigned long addr)
2301 unsigned long flags;
2304 spin_lock_irqsave(&modlist_lock, flags);
2306 list_for_each_entry(mod, &modules, list) {
2307 if (within(addr, mod->module_core, mod->core_size)) {
2308 spin_unlock_irqrestore(&modlist_lock, flags);
2313 spin_unlock_irqrestore(&modlist_lock, flags);
2319 /* Is this a valid kernel address? We don't grab the lock: we are oopsing. */
2320 struct module *__module_text_address(unsigned long addr)
2324 list_for_each_entry(mod, &modules, list)
2325 if (within(addr, mod->module_init, mod->init_text_size)
2326 || within(addr, mod->module_core, mod->core_text_size))
2331 struct module *module_text_address(unsigned long addr)
2334 unsigned long flags;
2336 spin_lock_irqsave(&modlist_lock, flags);
2337 mod = __module_text_address(addr);
2338 spin_unlock_irqrestore(&modlist_lock, flags);
2343 /* Don't grab lock, we're oopsing. */
2344 void print_modules(void)
2349 printk("Modules linked in:");
2350 list_for_each_entry(mod, &modules, list)
2351 printk(" %s%s", mod->name, taint_flags(mod->taints, buf));
2356 static char *make_driver_name(struct device_driver *drv)
2360 driver_name = kmalloc(strlen(drv->name) + strlen(drv->bus->name) + 2,
2365 sprintf(driver_name, "%s:%s", drv->bus->name, drv->name);
2369 static void module_create_drivers_dir(struct module_kobject *mk)
2371 if (!mk || mk->drivers_dir)
2374 mk->drivers_dir = kobject_add_dir(&mk->kobj, "drivers");
2377 void module_add_driver(struct module *mod, struct device_driver *drv)
2381 struct module_kobject *mk = NULL;
2388 else if (drv->mod_name) {
2389 struct kobject *mkobj;
2391 /* Lookup built-in module entry in /sys/modules */
2392 mkobj = kset_find_obj(&module_subsys.kset, drv->mod_name);
2394 mk = container_of(mkobj, struct module_kobject, kobj);
2400 /* Don't check return codes; these calls are idempotent */
2401 no_warn = sysfs_create_link(&drv->kobj, &mk->kobj, "module");
2402 driver_name = make_driver_name(drv);
2404 module_create_drivers_dir(mk);
2405 no_warn = sysfs_create_link(mk->drivers_dir, &drv->kobj,
2410 EXPORT_SYMBOL(module_add_driver);
2412 void module_remove_driver(struct device_driver *drv)
2419 sysfs_remove_link(&drv->kobj, "module");
2420 if (drv->owner && drv->owner->mkobj.drivers_dir) {
2421 driver_name = make_driver_name(drv);
2423 sysfs_remove_link(drv->owner->mkobj.drivers_dir,
2429 EXPORT_SYMBOL(module_remove_driver);
2432 #ifdef CONFIG_MODVERSIONS
2433 /* Generate the signature for struct module here, too, for modversions. */
2434 void struct_module(struct module *mod) { return; }
2435 EXPORT_SYMBOL(struct_module);