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>
47 #include "module-verify.h"
52 #define DEBUGP(fmt , a...)
55 #ifndef ARCH_SHF_SMALL
56 #define ARCH_SHF_SMALL 0
59 /* If this is set, the section belongs in the init part of the module */
60 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
62 /* Protects module list */
63 static DEFINE_SPINLOCK(modlist_lock);
65 /* List of modules, protected by module_mutex AND modlist_lock */
66 static DEFINE_MUTEX(module_mutex);
67 static LIST_HEAD(modules);
69 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
71 int register_module_notifier(struct notifier_block * nb)
73 return blocking_notifier_chain_register(&module_notify_list, nb);
75 EXPORT_SYMBOL(register_module_notifier);
77 int unregister_module_notifier(struct notifier_block * nb)
79 return blocking_notifier_chain_unregister(&module_notify_list, nb);
81 EXPORT_SYMBOL(unregister_module_notifier);
83 /* We require a truly strong try_module_get() */
84 static inline int strong_try_module_get(struct module *mod)
86 if (mod && mod->state == MODULE_STATE_COMING)
88 return try_module_get(mod);
91 static inline void add_taint_module(struct module *mod, unsigned flag)
97 /* A thread that wants to hold a reference to a module only while it
98 * is running can call ths to safely exit.
99 * nfsd and lockd use this.
101 void __module_put_and_exit(struct module *mod, long code)
106 EXPORT_SYMBOL(__module_put_and_exit);
108 /* Find a module section: 0 means not found. */
109 static unsigned int find_sec(Elf_Ehdr *hdr,
111 const char *secstrings,
116 for (i = 1; i < hdr->e_shnum; i++)
117 /* Alloc bit cleared means "ignore it." */
118 if ((sechdrs[i].sh_flags & SHF_ALLOC)
119 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
124 /* Provided by the linker */
125 extern const struct kernel_symbol __start___ksymtab[];
126 extern const struct kernel_symbol __stop___ksymtab[];
127 extern const struct kernel_symbol __start___ksymtab_gpl[];
128 extern const struct kernel_symbol __stop___ksymtab_gpl[];
129 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
130 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
131 extern const struct kernel_symbol __start___ksymtab_unused[];
132 extern const struct kernel_symbol __stop___ksymtab_unused[];
133 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
134 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
135 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
136 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
137 extern const unsigned long __start___kcrctab[];
138 extern const unsigned long __start___kcrctab_gpl[];
139 extern const unsigned long __start___kcrctab_gpl_future[];
140 extern const unsigned long __start___kcrctab_unused[];
141 extern const unsigned long __start___kcrctab_unused_gpl[];
143 #ifndef CONFIG_MODVERSIONS
144 #define symversion(base, idx) NULL
146 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
149 /* lookup symbol in given range of kernel_symbols */
150 static const struct kernel_symbol *lookup_symbol(const char *name,
151 const struct kernel_symbol *start,
152 const struct kernel_symbol *stop)
154 const struct kernel_symbol *ks = start;
155 for (; ks < stop; ks++)
156 if (strcmp(ks->name, name) == 0)
161 static void printk_unused_warning(const char *name)
163 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
164 "however this module is using it.\n", name);
165 printk(KERN_WARNING "This symbol will go away in the future.\n");
166 printk(KERN_WARNING "Please evalute if this is the right api to use, "
167 "and if it really is, submit a report the linux kernel "
168 "mailinglist together with submitting your code for "
172 /* Find a symbol, return value, crc and module which owns it */
173 static unsigned long __find_symbol(const char *name,
174 struct module **owner,
175 const unsigned long **crc,
179 const struct kernel_symbol *ks;
181 /* Core kernel first. */
183 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
185 *crc = symversion(__start___kcrctab, (ks - __start___ksymtab));
189 ks = lookup_symbol(name, __start___ksymtab_gpl,
190 __stop___ksymtab_gpl);
192 *crc = symversion(__start___kcrctab_gpl,
193 (ks - __start___ksymtab_gpl));
197 ks = lookup_symbol(name, __start___ksymtab_gpl_future,
198 __stop___ksymtab_gpl_future);
201 printk(KERN_WARNING "Symbol %s is being used "
202 "by a non-GPL module, which will not "
203 "be allowed in the future\n", name);
204 printk(KERN_WARNING "Please see the file "
205 "Documentation/feature-removal-schedule.txt "
206 "in the kernel source tree for more "
209 *crc = symversion(__start___kcrctab_gpl_future,
210 (ks - __start___ksymtab_gpl_future));
214 ks = lookup_symbol(name, __start___ksymtab_unused,
215 __stop___ksymtab_unused);
217 printk_unused_warning(name);
218 *crc = symversion(__start___kcrctab_unused,
219 (ks - __start___ksymtab_unused));
224 ks = lookup_symbol(name, __start___ksymtab_unused_gpl,
225 __stop___ksymtab_unused_gpl);
227 printk_unused_warning(name);
228 *crc = symversion(__start___kcrctab_unused_gpl,
229 (ks - __start___ksymtab_unused_gpl));
233 /* Now try modules. */
234 list_for_each_entry(mod, &modules, list) {
236 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
238 *crc = symversion(mod->crcs, (ks - mod->syms));
243 ks = lookup_symbol(name, mod->gpl_syms,
244 mod->gpl_syms + mod->num_gpl_syms);
246 *crc = symversion(mod->gpl_crcs,
247 (ks - mod->gpl_syms));
251 ks = lookup_symbol(name, mod->unused_syms, mod->unused_syms + mod->num_unused_syms);
253 printk_unused_warning(name);
254 *crc = symversion(mod->unused_crcs, (ks - mod->unused_syms));
259 ks = lookup_symbol(name, mod->unused_gpl_syms,
260 mod->unused_gpl_syms + mod->num_unused_gpl_syms);
262 printk_unused_warning(name);
263 *crc = symversion(mod->unused_gpl_crcs,
264 (ks - mod->unused_gpl_syms));
268 ks = lookup_symbol(name, mod->gpl_future_syms,
269 (mod->gpl_future_syms +
270 mod->num_gpl_future_syms));
273 printk(KERN_WARNING "Symbol %s is being used "
274 "by a non-GPL module, which will not "
275 "be allowed in the future\n", name);
276 printk(KERN_WARNING "Please see the file "
277 "Documentation/feature-removal-schedule.txt "
278 "in the kernel source tree for more "
281 *crc = symversion(mod->gpl_future_crcs,
282 (ks - mod->gpl_future_syms));
286 DEBUGP("Failed to find symbol %s\n", name);
290 /* Search for module by name: must hold module_mutex. */
291 static struct module *find_module(const char *name)
295 list_for_each_entry(mod, &modules, list) {
296 if (strcmp(mod->name, name) == 0)
303 /* Number of blocks used and allocated. */
304 static unsigned int pcpu_num_used, pcpu_num_allocated;
305 /* Size of each block. -ve means used. */
306 static int *pcpu_size;
308 static int split_block(unsigned int i, unsigned short size)
310 /* Reallocation required? */
311 if (pcpu_num_used + 1 > pcpu_num_allocated) {
312 int *new = kmalloc(sizeof(new[0]) * pcpu_num_allocated*2,
317 memcpy(new, pcpu_size, sizeof(new[0])*pcpu_num_allocated);
318 pcpu_num_allocated *= 2;
323 /* Insert a new subblock */
324 memmove(&pcpu_size[i+1], &pcpu_size[i],
325 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
328 pcpu_size[i+1] -= size;
333 static inline unsigned int block_size(int val)
340 /* Created by linker magic */
341 extern char __per_cpu_start[], __per_cpu_end[];
343 static void *percpu_modalloc(unsigned long size, unsigned long align,
350 if (align > SMP_CACHE_BYTES) {
351 printk(KERN_WARNING "%s: per-cpu alignment %li > %i\n",
352 name, align, SMP_CACHE_BYTES);
353 align = SMP_CACHE_BYTES;
356 ptr = __per_cpu_start;
357 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
358 /* Extra for alignment requirement. */
359 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
360 BUG_ON(i == 0 && extra != 0);
362 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
365 /* Transfer extra to previous block. */
366 if (pcpu_size[i-1] < 0)
367 pcpu_size[i-1] -= extra;
369 pcpu_size[i-1] += extra;
370 pcpu_size[i] -= extra;
373 /* Split block if warranted */
374 if (pcpu_size[i] - size > sizeof(unsigned long))
375 if (!split_block(i, size))
379 pcpu_size[i] = -pcpu_size[i];
383 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
388 static void percpu_modfree(void *freeme)
391 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
393 /* First entry is core kernel percpu data. */
394 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
396 pcpu_size[i] = -pcpu_size[i];
403 /* Merge with previous? */
404 if (pcpu_size[i-1] >= 0) {
405 pcpu_size[i-1] += pcpu_size[i];
407 memmove(&pcpu_size[i], &pcpu_size[i+1],
408 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
411 /* Merge with next? */
412 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
413 pcpu_size[i] += pcpu_size[i+1];
415 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
416 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
420 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
422 const char *secstrings)
424 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
427 static int percpu_modinit(void)
430 pcpu_num_allocated = 2;
431 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
433 /* Static in-kernel percpu data (used). */
434 pcpu_size[0] = -ALIGN(__per_cpu_end-__per_cpu_start, SMP_CACHE_BYTES);
436 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
437 if (pcpu_size[1] < 0) {
438 printk(KERN_ERR "No per-cpu room for modules.\n");
444 __initcall(percpu_modinit);
445 #else /* ... !CONFIG_SMP */
446 static inline void *percpu_modalloc(unsigned long size, unsigned long align,
451 static inline void percpu_modfree(void *pcpuptr)
455 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
457 const char *secstrings)
461 static inline void percpu_modcopy(void *pcpudst, const void *src,
464 /* pcpusec should be 0, and size of that section should be 0. */
467 #endif /* CONFIG_SMP */
469 #define MODINFO_ATTR(field) \
470 static void setup_modinfo_##field(struct module *mod, const char *s) \
472 mod->field = kstrdup(s, GFP_KERNEL); \
474 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
475 struct module *mod, char *buffer) \
477 return sprintf(buffer, "%s\n", mod->field); \
479 static int modinfo_##field##_exists(struct module *mod) \
481 return mod->field != NULL; \
483 static void free_modinfo_##field(struct module *mod) \
488 static struct module_attribute modinfo_##field = { \
489 .attr = { .name = __stringify(field), .mode = 0444, \
490 .owner = THIS_MODULE }, \
491 .show = show_modinfo_##field, \
492 .setup = setup_modinfo_##field, \
493 .test = modinfo_##field##_exists, \
494 .free = free_modinfo_##field, \
497 MODINFO_ATTR(version);
498 MODINFO_ATTR(srcversion);
500 #ifdef CONFIG_MODULE_UNLOAD
501 /* Init the unload section of the module. */
502 static void module_unload_init(struct module *mod)
506 INIT_LIST_HEAD(&mod->modules_which_use_me);
507 for (i = 0; i < NR_CPUS; i++)
508 local_set(&mod->ref[i].count, 0);
509 /* Hold reference count during initialization. */
510 local_set(&mod->ref[raw_smp_processor_id()].count, 1);
511 /* Backwards compatibility macros put refcount during init. */
512 mod->waiter = current;
515 /* modules using other modules */
518 struct list_head list;
519 struct module *module_which_uses;
522 /* Does a already use b? */
523 static int already_uses(struct module *a, struct module *b)
525 struct module_use *use;
527 list_for_each_entry(use, &b->modules_which_use_me, list) {
528 if (use->module_which_uses == a) {
529 DEBUGP("%s uses %s!\n", a->name, b->name);
533 DEBUGP("%s does not use %s!\n", a->name, b->name);
537 /* Module a uses b */
538 static int use_module(struct module *a, struct module *b)
540 struct module_use *use;
541 if (b == NULL || already_uses(a, b)) return 1;
543 if (!strong_try_module_get(b))
546 DEBUGP("Allocating new usage for %s.\n", a->name);
547 use = kmalloc(sizeof(*use), GFP_ATOMIC);
549 printk("%s: out of memory loading\n", a->name);
554 use->module_which_uses = a;
555 list_add(&use->list, &b->modules_which_use_me);
559 /* Clear the unload stuff of the module. */
560 static void module_unload_free(struct module *mod)
564 list_for_each_entry(i, &modules, list) {
565 struct module_use *use;
567 list_for_each_entry(use, &i->modules_which_use_me, list) {
568 if (use->module_which_uses == mod) {
569 DEBUGP("%s unusing %s\n", mod->name, i->name);
571 list_del(&use->list);
573 /* There can be at most one match. */
580 #ifdef CONFIG_MODULE_FORCE_UNLOAD
581 static inline int try_force_unload(unsigned int flags)
583 int ret = (flags & O_TRUNC);
585 add_taint(TAINT_FORCED_RMMOD);
589 static inline int try_force_unload(unsigned int flags)
593 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
602 /* Whole machine is stopped with interrupts off when this runs. */
603 static int __try_stop_module(void *_sref)
605 struct stopref *sref = _sref;
607 /* If it's not unused, quit unless we are told to block. */
608 if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
609 if (!(*sref->forced = try_force_unload(sref->flags)))
613 /* Mark it as dying. */
614 sref->mod->state = MODULE_STATE_GOING;
618 static int try_stop_module(struct module *mod, int flags, int *forced)
620 struct stopref sref = { mod, flags, forced };
622 return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
625 unsigned int module_refcount(struct module *mod)
627 unsigned int i, total = 0;
629 for (i = 0; i < NR_CPUS; i++)
630 total += local_read(&mod->ref[i].count);
633 EXPORT_SYMBOL(module_refcount);
635 /* This exists whether we can unload or not */
636 static void free_module(struct module *mod);
638 static void wait_for_zero_refcount(struct module *mod)
640 /* Since we might sleep for some time, drop the semaphore first */
641 mutex_unlock(&module_mutex);
643 DEBUGP("Looking at refcount...\n");
644 set_current_state(TASK_UNINTERRUPTIBLE);
645 if (module_refcount(mod) == 0)
649 current->state = TASK_RUNNING;
650 mutex_lock(&module_mutex);
654 sys_delete_module(const char __user *name_user, unsigned int flags)
657 char name[MODULE_NAME_LEN];
660 if (!capable(CAP_SYS_MODULE))
663 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
665 name[MODULE_NAME_LEN-1] = '\0';
667 if (mutex_lock_interruptible(&module_mutex) != 0)
670 mod = find_module(name);
676 if (!list_empty(&mod->modules_which_use_me)) {
677 /* Other modules depend on us: get rid of them first. */
682 /* Doing init or already dying? */
683 if (mod->state != MODULE_STATE_LIVE) {
684 /* FIXME: if (force), slam module count and wake up
686 DEBUGP("%s already dying\n", mod->name);
691 /* If it has an init func, it must have an exit func to unload */
692 if ((mod->init != NULL && mod->exit == NULL)
694 forced = try_force_unload(flags);
696 /* This module can't be removed */
702 /* Set this up before setting mod->state */
703 mod->waiter = current;
705 /* Stop the machine so refcounts can't move and disable module. */
706 ret = try_stop_module(mod, flags, &forced);
710 /* Never wait if forced. */
711 if (!forced && module_refcount(mod) != 0)
712 wait_for_zero_refcount(mod);
714 /* Final destruction now noone is using it. */
715 if (mod->exit != NULL) {
716 mutex_unlock(&module_mutex);
718 mutex_lock(&module_mutex);
723 mutex_unlock(&module_mutex);
727 static void print_unload_info(struct seq_file *m, struct module *mod)
729 struct module_use *use;
730 int printed_something = 0;
732 seq_printf(m, " %u ", module_refcount(mod));
734 /* Always include a trailing , so userspace can differentiate
735 between this and the old multi-field proc format. */
736 list_for_each_entry(use, &mod->modules_which_use_me, list) {
737 printed_something = 1;
738 seq_printf(m, "%s,", use->module_which_uses->name);
742 printed_something = 1;
743 seq_printf(m, "[unsafe],");
746 if (mod->init != NULL && mod->exit == NULL) {
747 printed_something = 1;
748 seq_printf(m, "[permanent],");
751 if (!printed_something)
755 void __symbol_put(const char *symbol)
757 struct module *owner;
759 const unsigned long *crc;
761 spin_lock_irqsave(&modlist_lock, flags);
762 if (!__find_symbol(symbol, &owner, &crc, 1))
765 spin_unlock_irqrestore(&modlist_lock, flags);
767 EXPORT_SYMBOL(__symbol_put);
769 void symbol_put_addr(void *addr)
771 struct module *modaddr;
773 if (core_kernel_text((unsigned long)addr))
776 if (!(modaddr = module_text_address((unsigned long)addr)))
780 EXPORT_SYMBOL_GPL(symbol_put_addr);
782 static ssize_t show_refcnt(struct module_attribute *mattr,
783 struct module *mod, char *buffer)
785 /* sysfs holds a reference */
786 return sprintf(buffer, "%u\n", module_refcount(mod)-1);
789 static struct module_attribute refcnt = {
790 .attr = { .name = "refcnt", .mode = 0444, .owner = THIS_MODULE },
794 void module_put(struct module *module)
797 unsigned int cpu = get_cpu();
798 local_dec(&module->ref[cpu].count);
799 /* Maybe they're waiting for us to drop reference? */
800 if (unlikely(!module_is_live(module)))
801 wake_up_process(module->waiter);
805 EXPORT_SYMBOL(module_put);
807 #else /* !CONFIG_MODULE_UNLOAD */
808 static void print_unload_info(struct seq_file *m, struct module *mod)
810 /* We don't know the usage count, or what modules are using. */
811 seq_printf(m, " - -");
814 static inline void module_unload_free(struct module *mod)
818 static inline int use_module(struct module *a, struct module *b)
820 return strong_try_module_get(b);
823 static inline void module_unload_init(struct module *mod)
826 #endif /* CONFIG_MODULE_UNLOAD */
828 static ssize_t show_initstate(struct module_attribute *mattr,
829 struct module *mod, char *buffer)
831 const char *state = "unknown";
833 switch (mod->state) {
834 case MODULE_STATE_LIVE:
837 case MODULE_STATE_COMING:
840 case MODULE_STATE_GOING:
844 return sprintf(buffer, "%s\n", state);
847 static struct module_attribute initstate = {
848 .attr = { .name = "initstate", .mode = 0444, .owner = THIS_MODULE },
849 .show = show_initstate,
852 static struct module_attribute *modinfo_attrs[] = {
856 #ifdef CONFIG_MODULE_UNLOAD
862 static const char vermagic[] = VERMAGIC_STRING;
864 #ifdef CONFIG_MODVERSIONS
865 static int check_version(Elf_Shdr *sechdrs,
866 unsigned int versindex,
869 const unsigned long *crc)
871 unsigned int i, num_versions;
872 struct modversion_info *versions;
874 /* Exporting module didn't supply crcs? OK, we're already tainted. */
878 versions = (void *) sechdrs[versindex].sh_addr;
879 num_versions = sechdrs[versindex].sh_size
880 / sizeof(struct modversion_info);
882 for (i = 0; i < num_versions; i++) {
883 if (strcmp(versions[i].name, symname) != 0)
886 if (versions[i].crc == *crc)
888 printk("%s: disagrees about version of symbol %s\n",
890 DEBUGP("Found checksum %lX vs module %lX\n",
891 *crc, versions[i].crc);
894 /* Not in module's version table. OK, but that taints the kernel. */
895 if (!(tainted & TAINT_FORCED_MODULE))
896 printk("%s: no version for \"%s\" found: kernel tainted.\n",
898 add_taint_module(mod, TAINT_FORCED_MODULE);
902 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
903 unsigned int versindex,
906 const unsigned long *crc;
907 struct module *owner;
909 if (!__find_symbol("struct_module", &owner, &crc, 1))
911 return check_version(sechdrs, versindex, "struct_module", mod,
915 /* First part is kernel version, which we ignore. */
916 static inline int same_magic(const char *amagic, const char *bmagic)
918 amagic += strcspn(amagic, " ");
919 bmagic += strcspn(bmagic, " ");
920 return strcmp(amagic, bmagic) == 0;
923 static inline int check_version(Elf_Shdr *sechdrs,
924 unsigned int versindex,
927 const unsigned long *crc)
932 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
933 unsigned int versindex,
939 static inline int same_magic(const char *amagic, const char *bmagic)
941 return strcmp(amagic, bmagic) == 0;
943 #endif /* CONFIG_MODVERSIONS */
945 /* Resolve a symbol for this module. I.e. if we find one, record usage.
946 Must be holding module_mutex. */
947 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
948 unsigned int versindex,
952 struct module *owner;
954 const unsigned long *crc;
956 ret = __find_symbol(name, &owner, &crc,
957 !(mod->taints & TAINT_PROPRIETARY_MODULE));
959 /* use_module can fail due to OOM, or module unloading */
960 if (!check_version(sechdrs, versindex, name, mod, crc) ||
961 !use_module(mod, owner))
969 * /sys/module/foo/sections stuff
970 * J. Corbet <corbet@lwn.net>
972 #ifdef CONFIG_KALLSYMS
973 static ssize_t module_sect_show(struct module_attribute *mattr,
974 struct module *mod, char *buf)
976 struct module_sect_attr *sattr =
977 container_of(mattr, struct module_sect_attr, mattr);
978 return sprintf(buf, "0x%lx\n", sattr->address);
981 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
985 for (section = 0; section < sect_attrs->nsections; section++)
986 kfree(sect_attrs->attrs[section].name);
990 static void add_sect_attrs(struct module *mod, unsigned int nsect,
991 char *secstrings, Elf_Shdr *sechdrs)
993 unsigned int nloaded = 0, i, size[2];
994 struct module_sect_attrs *sect_attrs;
995 struct module_sect_attr *sattr;
996 struct attribute **gattr;
998 /* Count loaded sections and allocate structures */
999 for (i = 0; i < nsect; i++)
1000 if (sechdrs[i].sh_flags & SHF_ALLOC)
1002 size[0] = ALIGN(sizeof(*sect_attrs)
1003 + nloaded * sizeof(sect_attrs->attrs[0]),
1004 sizeof(sect_attrs->grp.attrs[0]));
1005 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1006 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1007 if (sect_attrs == NULL)
1010 /* Setup section attributes. */
1011 sect_attrs->grp.name = "sections";
1012 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1014 sect_attrs->nsections = 0;
1015 sattr = §_attrs->attrs[0];
1016 gattr = §_attrs->grp.attrs[0];
1017 for (i = 0; i < nsect; i++) {
1018 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1020 sattr->address = sechdrs[i].sh_addr;
1021 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1023 if (sattr->name == NULL)
1025 sect_attrs->nsections++;
1026 sattr->mattr.show = module_sect_show;
1027 sattr->mattr.store = NULL;
1028 sattr->mattr.attr.name = sattr->name;
1029 sattr->mattr.attr.owner = mod;
1030 sattr->mattr.attr.mode = S_IRUGO;
1031 *(gattr++) = &(sattr++)->mattr.attr;
1035 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1038 mod->sect_attrs = sect_attrs;
1041 free_sect_attrs(sect_attrs);
1044 static void remove_sect_attrs(struct module *mod)
1046 if (mod->sect_attrs) {
1047 sysfs_remove_group(&mod->mkobj.kobj,
1048 &mod->sect_attrs->grp);
1049 /* We are positive that no one is using any sect attrs
1050 * at this point. Deallocate immediately. */
1051 free_sect_attrs(mod->sect_attrs);
1052 mod->sect_attrs = NULL;
1058 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1059 char *sectstrings, Elf_Shdr *sechdrs)
1063 static inline void remove_sect_attrs(struct module *mod)
1066 #endif /* CONFIG_KALLSYMS */
1068 static int module_add_modinfo_attrs(struct module *mod)
1070 struct module_attribute *attr;
1071 struct module_attribute *temp_attr;
1075 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1076 (ARRAY_SIZE(modinfo_attrs) + 1)),
1078 if (!mod->modinfo_attrs)
1081 temp_attr = mod->modinfo_attrs;
1082 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1084 (attr->test && attr->test(mod))) {
1085 memcpy(temp_attr, attr, sizeof(*temp_attr));
1086 temp_attr->attr.owner = mod;
1087 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1094 static void module_remove_modinfo_attrs(struct module *mod)
1096 struct module_attribute *attr;
1099 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1100 /* pick a field to test for end of list */
1101 if (!attr->attr.name)
1103 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1107 kfree(mod->modinfo_attrs);
1110 static int mod_sysfs_setup(struct module *mod,
1111 struct kernel_param *kparam,
1112 unsigned int num_params)
1116 if (!module_subsys.kset.subsys) {
1117 printk(KERN_ERR "%s: module_subsys not initialized\n",
1122 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1123 err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name);
1126 kobj_set_kset_s(&mod->mkobj, module_subsys);
1127 mod->mkobj.mod = mod;
1129 /* delay uevent until full sysfs population */
1130 kobject_init(&mod->mkobj.kobj);
1131 err = kobject_add(&mod->mkobj.kobj);
1135 mod->drivers_dir = kobject_add_dir(&mod->mkobj.kobj, "drivers");
1136 if (!mod->drivers_dir) {
1141 err = module_param_sysfs_setup(mod, kparam, num_params);
1143 goto out_unreg_drivers;
1145 err = module_add_modinfo_attrs(mod);
1147 goto out_unreg_param;
1149 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1153 module_param_sysfs_remove(mod);
1155 kobject_unregister(mod->drivers_dir);
1157 kobject_del(&mod->mkobj.kobj);
1158 kobject_put(&mod->mkobj.kobj);
1163 static void mod_kobject_remove(struct module *mod)
1165 module_remove_modinfo_attrs(mod);
1166 module_param_sysfs_remove(mod);
1167 kobject_unregister(mod->drivers_dir);
1169 kobject_unregister(&mod->mkobj.kobj);
1173 * unlink the module with the whole machine is stopped with interrupts off
1174 * - this defends against kallsyms not taking locks
1176 static int __unlink_module(void *_mod)
1178 struct module *mod = _mod;
1179 list_del(&mod->list);
1183 /* Free a module, remove from lists, etc (must hold module mutex). */
1184 static void free_module(struct module *mod)
1186 /* Delete from various lists */
1187 stop_machine_run(__unlink_module, mod, NR_CPUS);
1188 remove_sect_attrs(mod);
1189 mod_kobject_remove(mod);
1191 unwind_remove_table(mod->unwind_info, 0);
1193 /* Arch-specific cleanup. */
1194 module_arch_cleanup(mod);
1196 /* Module unload stuff */
1197 module_unload_free(mod);
1199 /* This may be NULL, but that's OK */
1200 module_free(mod, mod->module_init);
1203 percpu_modfree(mod->percpu);
1205 /* Free lock-classes: */
1206 lockdep_free_key_range(mod->module_core, mod->core_size);
1208 /* Finally, free the core (containing the module structure) */
1209 module_free(mod, mod->module_core);
1212 void *__symbol_get(const char *symbol)
1214 struct module *owner;
1215 unsigned long value, flags;
1216 const unsigned long *crc;
1218 spin_lock_irqsave(&modlist_lock, flags);
1219 value = __find_symbol(symbol, &owner, &crc, 1);
1220 if (value && !strong_try_module_get(owner))
1222 spin_unlock_irqrestore(&modlist_lock, flags);
1224 return (void *)value;
1226 EXPORT_SYMBOL_GPL(__symbol_get);
1229 * Ensure that an exported symbol [global namespace] does not already exist
1230 * in the Kernel or in some other modules exported symbol table.
1232 static int verify_export_symbols(struct module *mod)
1234 const char *name = NULL;
1235 unsigned long i, ret = 0;
1236 struct module *owner;
1237 const unsigned long *crc;
1239 for (i = 0; i < mod->num_syms; i++)
1240 if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) {
1241 name = mod->syms[i].name;
1246 for (i = 0; i < mod->num_gpl_syms; i++)
1247 if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) {
1248 name = mod->gpl_syms[i].name;
1255 printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
1256 mod->name, name, module_name(owner));
1261 /* Change all symbols so that sh_value encodes the pointer directly. */
1262 static int simplify_symbols(Elf_Shdr *sechdrs,
1263 unsigned int symindex,
1265 unsigned int versindex,
1266 unsigned int pcpuindex,
1269 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1270 unsigned long secbase;
1271 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1274 for (i = 1; i < n; i++) {
1275 switch (sym[i].st_shndx) {
1277 /* We compiled with -fno-common. These are not
1278 supposed to happen. */
1279 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1280 printk("%s: please compile with -fno-common\n",
1286 /* Don't need to do anything */
1287 DEBUGP("Absolute symbol: 0x%08lx\n",
1288 (long)sym[i].st_value);
1293 = resolve_symbol(sechdrs, versindex,
1294 strtab + sym[i].st_name, mod);
1296 /* Ok if resolved. */
1297 if (sym[i].st_value != 0)
1300 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1303 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1304 mod->name, strtab + sym[i].st_name);
1309 /* Divert to percpu allocation if a percpu var. */
1310 if (sym[i].st_shndx == pcpuindex)
1311 secbase = (unsigned long)mod->percpu;
1313 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1314 sym[i].st_value += secbase;
1322 /* Update size with this section: return offset. */
1323 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
1327 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1328 *size = ret + sechdr->sh_size;
1332 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1333 might -- code, read-only data, read-write data, small data. Tally
1334 sizes, and place the offsets into sh_entsize fields: high bit means it
1336 static void layout_sections(struct module *mod,
1337 const Elf_Ehdr *hdr,
1339 const char *secstrings)
1341 static unsigned long const masks[][2] = {
1342 /* NOTE: all executable code must be the first section
1343 * in this array; otherwise modify the text_size
1344 * finder in the two loops below */
1345 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1346 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1347 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1348 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1352 for (i = 0; i < hdr->e_shnum; i++)
1353 sechdrs[i].sh_entsize = ~0UL;
1355 DEBUGP("Core section allocation order:\n");
1356 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1357 for (i = 0; i < hdr->e_shnum; ++i) {
1358 Elf_Shdr *s = &sechdrs[i];
1360 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1361 || (s->sh_flags & masks[m][1])
1362 || s->sh_entsize != ~0UL
1363 || strncmp(secstrings + s->sh_name,
1366 s->sh_entsize = get_offset(&mod->core_size, s);
1367 DEBUGP("\t%s\n", secstrings + s->sh_name);
1370 mod->core_text_size = mod->core_size;
1373 DEBUGP("Init section allocation order:\n");
1374 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1375 for (i = 0; i < hdr->e_shnum; ++i) {
1376 Elf_Shdr *s = &sechdrs[i];
1378 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1379 || (s->sh_flags & masks[m][1])
1380 || s->sh_entsize != ~0UL
1381 || strncmp(secstrings + s->sh_name,
1384 s->sh_entsize = (get_offset(&mod->init_size, s)
1385 | INIT_OFFSET_MASK);
1386 DEBUGP("\t%s\n", secstrings + s->sh_name);
1389 mod->init_text_size = mod->init_size;
1393 static void set_license(struct module *mod, const char *license)
1396 license = "unspecified";
1398 if (!license_is_gpl_compatible(license)) {
1399 if (!(tainted & TAINT_PROPRIETARY_MODULE))
1400 printk(KERN_WARNING "%s: module license '%s' taints "
1401 "kernel.\n", mod->name, license);
1402 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1406 /* Parse tag=value strings from .modinfo section */
1407 static char *next_string(char *string, unsigned long *secsize)
1409 /* Skip non-zero chars */
1412 if ((*secsize)-- <= 1)
1416 /* Skip any zero padding. */
1417 while (!string[0]) {
1419 if ((*secsize)-- <= 1)
1425 static char *get_modinfo(Elf_Shdr *sechdrs,
1430 unsigned int taglen = strlen(tag);
1431 unsigned long size = sechdrs[info].sh_size;
1433 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1434 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1435 return p + taglen + 1;
1440 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1441 unsigned int infoindex)
1443 struct module_attribute *attr;
1446 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1449 get_modinfo(sechdrs,
1455 #ifdef CONFIG_KALLSYMS
1456 int is_exported(const char *name, const struct module *mod)
1458 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1461 if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1468 static char elf_type(const Elf_Sym *sym,
1470 const char *secstrings,
1473 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1474 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1479 if (sym->st_shndx == SHN_UNDEF)
1481 if (sym->st_shndx == SHN_ABS)
1483 if (sym->st_shndx >= SHN_LORESERVE)
1485 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1487 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1488 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1489 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1491 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1496 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1497 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1502 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1503 ".debug", strlen(".debug")) == 0)
1508 static void add_kallsyms(struct module *mod,
1510 unsigned int symindex,
1511 unsigned int strindex,
1512 const char *secstrings)
1516 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1517 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1518 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1520 /* Set types up while we still have access to sections. */
1521 for (i = 0; i < mod->num_symtab; i++)
1522 mod->symtab[i].st_info
1523 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1526 static inline void add_kallsyms(struct module *mod,
1528 unsigned int symindex,
1529 unsigned int strindex,
1530 const char *secstrings)
1533 #endif /* CONFIG_KALLSYMS */
1535 /* Allocate and load the module: note that size of section 0 is always
1536 zero, and we rely on this for optional sections. */
1537 static struct module *load_module(void __user *umod,
1539 const char __user *uargs)
1543 char *secstrings, *args, *modmagic, *strtab = NULL;
1545 unsigned int symindex = 0;
1546 unsigned int strindex = 0;
1547 unsigned int setupindex;
1548 unsigned int exindex;
1549 unsigned int exportindex;
1550 unsigned int modindex;
1551 unsigned int obsparmindex;
1552 unsigned int infoindex;
1553 unsigned int gplindex;
1554 unsigned int crcindex;
1555 unsigned int gplcrcindex;
1556 unsigned int versindex;
1557 unsigned int pcpuindex;
1558 unsigned int gplfutureindex;
1559 unsigned int gplfuturecrcindex;
1560 unsigned int unwindex = 0;
1561 unsigned int unusedindex;
1562 unsigned int unusedcrcindex;
1563 unsigned int unusedgplindex;
1564 unsigned int unusedgplcrcindex;
1567 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1568 struct exception_table_entry *extable;
1569 mm_segment_t old_fs;
1572 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1574 if (len < sizeof(*hdr))
1575 return ERR_PTR(-ENOEXEC);
1577 /* Suck in entire file: we'll want most of it. */
1578 /* vmalloc barfs on "unusual" numbers. Check here */
1579 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1580 return ERR_PTR(-ENOMEM);
1581 if (copy_from_user(hdr, umod, len) != 0) {
1586 /* Sanity checks against insmoding binaries or wrong arch,
1587 weird elf version */
1588 if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
1589 || hdr->e_type != ET_REL
1590 || !elf_check_arch(hdr)
1591 || hdr->e_shentsize != sizeof(*sechdrs)) {
1596 /* Verify the module's contents */
1598 err = module_verify(hdr, len);
1604 /* Convenience variables */
1605 sechdrs = (void *)hdr + hdr->e_shoff;
1606 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1607 sechdrs[0].sh_addr = 0;
1609 for (i = 1; i < hdr->e_shnum; i++) {
1610 if (sechdrs[i].sh_type != SHT_NOBITS
1611 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1614 /* Mark all sections sh_addr with their address in the
1616 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1618 /* Internal symbols and strings. */
1619 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1621 strindex = sechdrs[i].sh_link;
1622 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1624 #ifndef CONFIG_MODULE_UNLOAD
1625 /* Don't load .exit sections */
1626 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1627 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1631 modindex = find_sec(hdr, sechdrs, secstrings,
1632 ".gnu.linkonce.this_module");
1634 printk(KERN_WARNING "No module found in object\n");
1638 mod = (void *)sechdrs[modindex].sh_addr;
1639 mod->gpgsig_ok = gpgsig_ok;
1641 if (symindex == 0) {
1642 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1648 /* Optional sections */
1649 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1650 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1651 gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1652 unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
1653 unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
1654 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1655 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1656 gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1657 unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
1658 unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
1659 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1660 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1661 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1662 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1663 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1664 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1665 #ifdef ARCH_UNWIND_SECTION_NAME
1666 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1669 /* Don't keep modinfo section */
1670 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1671 #ifdef CONFIG_KALLSYMS
1672 /* Keep symbol and string tables for decoding later. */
1673 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1674 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1677 sechdrs[unwindex].sh_flags |= SHF_ALLOC;
1679 /* Check module struct version now, before we try to use module. */
1680 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1685 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1686 /* This is allowed: modprobe --force will invalidate it. */
1688 add_taint_module(mod, TAINT_FORCED_MODULE);
1689 printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
1691 } else if (!same_magic(modmagic, vermagic)) {
1692 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1693 mod->name, modmagic, vermagic);
1698 /* Now copy in args */
1699 args = strndup_user(uargs, ~0UL >> 1);
1701 err = PTR_ERR(args);
1705 if (find_module(mod->name)) {
1710 mod->state = MODULE_STATE_COMING;
1712 /* Allow arches to frob section contents and sizes. */
1713 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1718 /* We have a special allocation for this section. */
1719 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1720 sechdrs[pcpuindex].sh_addralign,
1726 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1727 mod->percpu = percpu;
1730 /* Determine total sizes, and put offsets in sh_entsize. For now
1731 this is done generically; there doesn't appear to be any
1732 special cases for the architectures. */
1733 layout_sections(mod, hdr, sechdrs, secstrings);
1735 /* Do the allocs. */
1736 ptr = module_alloc(mod->core_size);
1741 memset(ptr, 0, mod->core_size);
1742 mod->module_core = ptr;
1744 ptr = module_alloc(mod->init_size);
1745 if (!ptr && mod->init_size) {
1749 memset(ptr, 0, mod->init_size);
1750 mod->module_init = ptr;
1752 /* Transfer each section which specifies SHF_ALLOC */
1753 DEBUGP("final section addresses:\n");
1754 for (i = 0; i < hdr->e_shnum; i++) {
1757 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1760 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
1761 dest = mod->module_init
1762 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
1764 dest = mod->module_core + sechdrs[i].sh_entsize;
1766 if (sechdrs[i].sh_type != SHT_NOBITS)
1767 memcpy(dest, (void *)sechdrs[i].sh_addr,
1768 sechdrs[i].sh_size);
1769 /* Update sh_addr to point to copy in image. */
1770 sechdrs[i].sh_addr = (unsigned long)dest;
1771 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
1773 /* Module has been moved. */
1774 mod = (void *)sechdrs[modindex].sh_addr;
1776 /* Now we've moved module, initialize linked lists, etc. */
1777 module_unload_init(mod);
1779 /* Set up license info based on the info section */
1780 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
1782 if (strcmp(mod->name, "ndiswrapper") == 0)
1783 add_taint(TAINT_PROPRIETARY_MODULE);
1784 if (strcmp(mod->name, "driverloader") == 0)
1785 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1787 /* Set up MODINFO_ATTR fields */
1788 setup_modinfo(mod, sechdrs, infoindex);
1790 /* Fix up syms, so that st_value is a pointer to location. */
1791 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
1796 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
1797 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
1798 mod->syms = (void *)sechdrs[exportindex].sh_addr;
1800 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
1801 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
1802 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
1804 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
1805 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
1806 sizeof(*mod->gpl_future_syms);
1807 mod->num_unused_syms = sechdrs[unusedindex].sh_size /
1808 sizeof(*mod->unused_syms);
1809 mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
1810 sizeof(*mod->unused_gpl_syms);
1811 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
1812 if (gplfuturecrcindex)
1813 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
1815 mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
1817 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
1818 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
1819 if (unusedgplcrcindex)
1820 mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr;
1822 #ifdef CONFIG_MODVERSIONS
1823 if ((mod->num_syms && !crcindex) ||
1824 (mod->num_gpl_syms && !gplcrcindex) ||
1825 (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
1826 (mod->num_unused_syms && !unusedcrcindex) ||
1827 (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
1828 printk(KERN_WARNING "%s: No versions for exported symbols."
1829 " Tainting kernel.\n", mod->name);
1830 add_taint_module(mod, TAINT_FORCED_MODULE);
1834 /* Now do relocations. */
1835 for (i = 1; i < hdr->e_shnum; i++) {
1836 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1837 unsigned int info = sechdrs[i].sh_info;
1839 /* Not a valid relocation section? */
1840 if (info >= hdr->e_shnum)
1843 /* Don't bother with non-allocated sections */
1844 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1847 if (sechdrs[i].sh_type == SHT_REL)
1848 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
1849 else if (sechdrs[i].sh_type == SHT_RELA)
1850 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1856 /* Find duplicate symbols */
1857 err = verify_export_symbols(mod);
1862 /* Set up and sort exception table */
1863 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
1864 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
1865 sort_extable(extable, extable + mod->num_exentries);
1867 /* Finally, copy percpu area over. */
1868 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
1869 sechdrs[pcpuindex].sh_size);
1871 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
1873 err = module_finalize(hdr, sechdrs, mod);
1877 /* flush the icache in correct context */
1882 * Flush the instruction cache, since we've played with text.
1883 * Do it before processing of module parameters, so the module
1884 * can provide parameter accessor functions of its own.
1886 if (mod->module_init)
1887 flush_icache_range((unsigned long)mod->module_init,
1888 (unsigned long)mod->module_init
1890 flush_icache_range((unsigned long)mod->module_core,
1891 (unsigned long)mod->module_core + mod->core_size);
1897 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
1900 /* Size of section 0 is 0, so this works well if no params */
1901 err = parse_args(mod->name, mod->args,
1902 (struct kernel_param *)
1903 sechdrs[setupindex].sh_addr,
1904 sechdrs[setupindex].sh_size
1905 / sizeof(struct kernel_param),
1910 err = mod_sysfs_setup(mod,
1911 (struct kernel_param *)
1912 sechdrs[setupindex].sh_addr,
1913 sechdrs[setupindex].sh_size
1914 / sizeof(struct kernel_param));
1917 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
1919 /* Size of section 0 is 0, so this works well if no unwind info. */
1920 mod->unwind_info = unwind_add_table(mod,
1921 (void *)sechdrs[unwindex].sh_addr,
1922 sechdrs[unwindex].sh_size);
1924 /* Get rid of temporary copy */
1931 module_arch_cleanup(mod);
1933 module_unload_free(mod);
1934 module_free(mod, mod->module_init);
1936 module_free(mod, mod->module_core);
1939 percpu_modfree(percpu);
1944 return ERR_PTR(err);
1947 printk(KERN_ERR "Module len %lu truncated\n", len);
1953 * link the module with the whole machine is stopped with interrupts off
1954 * - this defends against kallsyms not taking locks
1956 static int __link_module(void *_mod)
1958 struct module *mod = _mod;
1959 list_add(&mod->list, &modules);
1963 /* This is where the real work happens */
1965 sys_init_module(void __user *umod,
1967 const char __user *uargs)
1972 /* Must have permission */
1973 if (!capable(CAP_SYS_MODULE))
1976 /* Only one module load at a time, please */
1977 if (mutex_lock_interruptible(&module_mutex) != 0)
1980 /* Do all the hard work */
1981 mod = load_module(umod, len, uargs);
1983 mutex_unlock(&module_mutex);
1984 return PTR_ERR(mod);
1987 /* Now sew it into the lists. They won't access us, since
1988 strong_try_module_get() will fail. */
1989 stop_machine_run(__link_module, mod, NR_CPUS);
1991 /* Drop lock so they can recurse */
1992 mutex_unlock(&module_mutex);
1994 blocking_notifier_call_chain(&module_notify_list,
1995 MODULE_STATE_COMING, mod);
1997 /* Start the module */
1998 if (mod->init != NULL)
2001 /* Init routine failed: abort. Try to protect us from
2002 buggy refcounters. */
2003 mod->state = MODULE_STATE_GOING;
2004 synchronize_sched();
2006 printk(KERN_ERR "%s: module is now stuck!\n",
2010 mutex_lock(&module_mutex);
2012 mutex_unlock(&module_mutex);
2017 /* Now it's a first class citizen! */
2018 mutex_lock(&module_mutex);
2019 mod->state = MODULE_STATE_LIVE;
2020 /* Drop initial reference. */
2022 unwind_remove_table(mod->unwind_info, 1);
2023 module_free(mod, mod->module_init);
2024 mod->module_init = NULL;
2026 mod->init_text_size = 0;
2027 mutex_unlock(&module_mutex);
2032 static inline int within(unsigned long addr, void *start, unsigned long size)
2034 return ((void *)addr >= start && (void *)addr < start + size);
2037 #ifdef CONFIG_KALLSYMS
2039 * This ignores the intensely annoying "mapping symbols" found
2040 * in ARM ELF files: $a, $t and $d.
2042 static inline int is_arm_mapping_symbol(const char *str)
2044 return str[0] == '$' && strchr("atd", str[1])
2045 && (str[2] == '\0' || str[2] == '.');
2048 static const char *get_ksymbol(struct module *mod,
2050 unsigned long *size,
2051 unsigned long *offset)
2053 unsigned int i, best = 0;
2054 unsigned long nextval;
2056 /* At worse, next value is at end of module */
2057 if (within(addr, mod->module_init, mod->init_size))
2058 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2060 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2062 /* Scan for closest preceeding symbol, and next symbol. (ELF
2063 starts real symbols at 1). */
2064 for (i = 1; i < mod->num_symtab; i++) {
2065 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2068 /* We ignore unnamed symbols: they're uninformative
2069 * and inserted at a whim. */
2070 if (mod->symtab[i].st_value <= addr
2071 && mod->symtab[i].st_value > mod->symtab[best].st_value
2072 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2073 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2075 if (mod->symtab[i].st_value > addr
2076 && mod->symtab[i].st_value < nextval
2077 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2078 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2079 nextval = mod->symtab[i].st_value;
2085 *size = nextval - mod->symtab[best].st_value;
2086 *offset = addr - mod->symtab[best].st_value;
2087 return mod->strtab + mod->symtab[best].st_name;
2090 /* For kallsyms to ask for address resolution. NULL means not found.
2091 We don't lock, as this is used for oops resolution and races are a
2093 const char *module_address_lookup(unsigned long addr,
2094 unsigned long *size,
2095 unsigned long *offset,
2100 list_for_each_entry(mod, &modules, list) {
2101 if (within(addr, mod->module_init, mod->init_size)
2102 || within(addr, mod->module_core, mod->core_size)) {
2104 *modname = mod->name;
2105 return get_ksymbol(mod, addr, size, offset);
2111 struct module *module_get_kallsym(unsigned int symnum, unsigned long *value,
2112 char *type, char *name, size_t namelen)
2116 mutex_lock(&module_mutex);
2117 list_for_each_entry(mod, &modules, list) {
2118 if (symnum < mod->num_symtab) {
2119 *value = mod->symtab[symnum].st_value;
2120 *type = mod->symtab[symnum].st_info;
2121 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2123 mutex_unlock(&module_mutex);
2126 symnum -= mod->num_symtab;
2128 mutex_unlock(&module_mutex);
2132 static unsigned long mod_find_symname(struct module *mod, const char *name)
2136 for (i = 0; i < mod->num_symtab; i++)
2137 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2138 mod->symtab[i].st_info != 'U')
2139 return mod->symtab[i].st_value;
2143 /* Look for this name: can be of form module:name. */
2144 unsigned long module_kallsyms_lookup_name(const char *name)
2148 unsigned long ret = 0;
2150 /* Don't lock: we're in enough trouble already. */
2151 if ((colon = strchr(name, ':')) != NULL) {
2153 if ((mod = find_module(name)) != NULL)
2154 ret = mod_find_symname(mod, colon+1);
2157 list_for_each_entry(mod, &modules, list)
2158 if ((ret = mod_find_symname(mod, name)) != 0)
2163 #endif /* CONFIG_KALLSYMS */
2165 /* Called by the /proc file system to return a list of modules. */
2166 static void *m_start(struct seq_file *m, loff_t *pos)
2168 struct list_head *i;
2171 mutex_lock(&module_mutex);
2172 list_for_each(i, &modules) {
2181 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2183 struct list_head *i = p;
2185 if (i->next == &modules)
2190 static void m_stop(struct seq_file *m, void *p)
2192 mutex_unlock(&module_mutex);
2195 static char *taint_flags(unsigned int taints, char *buf)
2201 if (taints & TAINT_PROPRIETARY_MODULE)
2203 if (taints & TAINT_FORCED_MODULE)
2206 * TAINT_FORCED_RMMOD: could be added.
2207 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2217 static int m_show(struct seq_file *m, void *p)
2219 struct module *mod = list_entry(p, struct module, list);
2222 seq_printf(m, "%s %lu",
2223 mod->name, mod->init_size + mod->core_size);
2224 print_unload_info(m, mod);
2226 /* Informative for users. */
2227 seq_printf(m, " %s",
2228 mod->state == MODULE_STATE_GOING ? "Unloading":
2229 mod->state == MODULE_STATE_COMING ? "Loading":
2231 /* Used by oprofile and other similar tools. */
2232 seq_printf(m, " 0x%p", mod->module_core);
2236 seq_printf(m, " %s", taint_flags(mod->taints, buf));
2238 seq_printf(m, "\n");
2242 /* Format: modulename size refcount deps address
2244 Where refcount is a number or -, and deps is a comma-separated list
2247 const struct seq_operations modules_op = {
2254 /* Given an address, look for it in the module exception tables. */
2255 const struct exception_table_entry *search_module_extables(unsigned long addr)
2257 unsigned long flags;
2258 const struct exception_table_entry *e = NULL;
2261 spin_lock_irqsave(&modlist_lock, flags);
2262 list_for_each_entry(mod, &modules, list) {
2263 if (mod->num_exentries == 0)
2266 e = search_extable(mod->extable,
2267 mod->extable + mod->num_exentries - 1,
2272 spin_unlock_irqrestore(&modlist_lock, flags);
2274 /* Now, if we found one, we are running inside it now, hence
2275 we cannot unload the module, hence no refcnt needed. */
2280 * Is this a valid module address?
2282 int is_module_address(unsigned long addr)
2284 unsigned long flags;
2287 spin_lock_irqsave(&modlist_lock, flags);
2289 list_for_each_entry(mod, &modules, list) {
2290 if (within(addr, mod->module_core, mod->core_size)) {
2291 spin_unlock_irqrestore(&modlist_lock, flags);
2296 spin_unlock_irqrestore(&modlist_lock, flags);
2302 /* Is this a valid kernel address? We don't grab the lock: we are oopsing. */
2303 struct module *__module_text_address(unsigned long addr)
2307 list_for_each_entry(mod, &modules, list)
2308 if (within(addr, mod->module_init, mod->init_text_size)
2309 || within(addr, mod->module_core, mod->core_text_size))
2314 struct module *module_text_address(unsigned long addr)
2317 unsigned long flags;
2319 spin_lock_irqsave(&modlist_lock, flags);
2320 mod = __module_text_address(addr);
2321 spin_unlock_irqrestore(&modlist_lock, flags);
2326 /* Don't grab lock, we're oopsing. */
2327 void print_modules(void)
2332 printk("Modules linked in:");
2333 list_for_each_entry(mod, &modules, list) {
2334 printk(" %s%s", mod->name, taint_flags(mod->taints, buf));
2335 #if CONFIG_MODULE_SIG
2336 if (!mod->gpgsig_ok)
2343 static char *make_driver_name(struct device_driver *drv)
2347 driver_name = kmalloc(strlen(drv->name) + strlen(drv->bus->name) + 2,
2352 sprintf(driver_name, "%s:%s", drv->bus->name, drv->name);
2356 void module_add_driver(struct module *mod, struct device_driver *drv)
2364 /* Don't check return codes; these calls are idempotent */
2365 no_warn = sysfs_create_link(&drv->kobj, &mod->mkobj.kobj, "module");
2366 driver_name = make_driver_name(drv);
2368 no_warn = sysfs_create_link(mod->drivers_dir, &drv->kobj,
2373 EXPORT_SYMBOL(module_add_driver);
2375 void module_remove_driver(struct device_driver *drv)
2382 sysfs_remove_link(&drv->kobj, "module");
2383 if (drv->owner && drv->owner->drivers_dir) {
2384 driver_name = make_driver_name(drv);
2386 sysfs_remove_link(drv->owner->drivers_dir,
2392 EXPORT_SYMBOL(module_remove_driver);
2394 #ifdef CONFIG_MODVERSIONS
2395 /* Generate the signature for struct module here, too, for modversions. */
2396 void struct_module(struct module *mod) { return; }
2397 EXPORT_SYMBOL(struct_module);