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/kallsyms.h>
23 #include <linux/sysfs.h>
24 #include <linux/kernel.h>
25 #include <linux/slab.h>
26 #include <linux/vmalloc.h>
27 #include <linux/elf.h>
28 #include <linux/seq_file.h>
29 #include <linux/syscalls.h>
30 #include <linux/fcntl.h>
31 #include <linux/rcupdate.h>
32 #include <linux/capability.h>
33 #include <linux/cpu.h>
34 #include <linux/moduleparam.h>
35 #include <linux/errno.h>
36 #include <linux/err.h>
37 #include <linux/vermagic.h>
38 #include <linux/notifier.h>
39 #include <linux/sched.h>
40 #include <linux/stop_machine.h>
41 #include <linux/device.h>
42 #include <linux/string.h>
43 #include <linux/mutex.h>
44 #include <linux/unwind.h>
45 #include <asm/uaccess.h>
46 #include <asm/semaphore.h>
47 #include <asm/cacheflush.h>
48 #include <linux/license.h>
53 #define DEBUGP(fmt , a...)
56 #ifndef ARCH_SHF_SMALL
57 #define ARCH_SHF_SMALL 0
60 /* If this is set, the section belongs in the init part of the module */
61 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
63 /* List of modules, protected by module_mutex or preempt_disable
64 * (add/delete uses stop_machine). */
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(): 0 means failure due to
83 ongoing or failed initialization etc. */
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)
98 * A thread that wants to hold a reference to a module only while it
99 * is running can call this to safely exit. 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) {
314 new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2,
319 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 > PAGE_SIZE) {
351 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
352 name, align, PAGE_SIZE);
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] = -(__per_cpu_end-__per_cpu_start);
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 .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);
657 sys_delete_module(const char __user *name_user, unsigned int flags)
660 char name[MODULE_NAME_LEN];
663 if (!capable(CAP_SYS_MODULE))
666 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
668 name[MODULE_NAME_LEN-1] = '\0';
670 if (mutex_lock_interruptible(&module_mutex) != 0)
673 mod = find_module(name);
679 if (!list_empty(&mod->modules_which_use_me)) {
680 /* Other modules depend on us: get rid of them first. */
685 /* Doing init or already dying? */
686 if (mod->state != MODULE_STATE_LIVE) {
687 /* FIXME: if (force), slam module count and wake up
689 DEBUGP("%s already dying\n", mod->name);
694 /* If it has an init func, it must have an exit func to unload */
695 if (mod->init && !mod->exit) {
696 forced = try_force_unload(flags);
698 /* This module can't be removed */
704 /* Set this up before setting mod->state */
705 mod->waiter = current;
707 /* Stop the machine so refcounts can't move and disable module. */
708 ret = try_stop_module(mod, flags, &forced);
712 /* Never wait if forced. */
713 if (!forced && module_refcount(mod) != 0)
714 wait_for_zero_refcount(mod);
716 /* Final destruction now noone is using it. */
717 if (mod->exit != NULL) {
718 mutex_unlock(&module_mutex);
720 mutex_lock(&module_mutex);
725 mutex_unlock(&module_mutex);
729 static void print_unload_info(struct seq_file *m, struct module *mod)
731 struct module_use *use;
732 int printed_something = 0;
734 seq_printf(m, " %u ", module_refcount(mod));
736 /* Always include a trailing , so userspace can differentiate
737 between this and the old multi-field proc format. */
738 list_for_each_entry(use, &mod->modules_which_use_me, list) {
739 printed_something = 1;
740 seq_printf(m, "%s,", use->module_which_uses->name);
743 if (mod->init != NULL && mod->exit == NULL) {
744 printed_something = 1;
745 seq_printf(m, "[permanent],");
748 if (!printed_something)
752 void __symbol_put(const char *symbol)
754 struct module *owner;
755 const unsigned long *crc;
758 if (!__find_symbol(symbol, &owner, &crc, 1))
763 EXPORT_SYMBOL(__symbol_put);
765 void symbol_put_addr(void *addr)
767 struct module *modaddr;
769 if (core_kernel_text((unsigned long)addr))
772 if (!(modaddr = module_text_address((unsigned long)addr)))
776 EXPORT_SYMBOL_GPL(symbol_put_addr);
778 static ssize_t show_refcnt(struct module_attribute *mattr,
779 struct module *mod, char *buffer)
781 return sprintf(buffer, "%u\n", module_refcount(mod));
784 static struct module_attribute refcnt = {
785 .attr = { .name = "refcnt", .mode = 0444 },
789 void module_put(struct module *module)
792 unsigned int cpu = get_cpu();
793 local_dec(&module->ref[cpu].count);
794 /* Maybe they're waiting for us to drop reference? */
795 if (unlikely(!module_is_live(module)))
796 wake_up_process(module->waiter);
800 EXPORT_SYMBOL(module_put);
802 #else /* !CONFIG_MODULE_UNLOAD */
803 static void print_unload_info(struct seq_file *m, struct module *mod)
805 /* We don't know the usage count, or what modules are using. */
806 seq_printf(m, " - -");
809 static inline void module_unload_free(struct module *mod)
813 static inline int use_module(struct module *a, struct module *b)
815 return strong_try_module_get(b);
818 static inline void module_unload_init(struct module *mod)
821 #endif /* CONFIG_MODULE_UNLOAD */
823 static ssize_t show_initstate(struct module_attribute *mattr,
824 struct module *mod, char *buffer)
826 const char *state = "unknown";
828 switch (mod->state) {
829 case MODULE_STATE_LIVE:
832 case MODULE_STATE_COMING:
835 case MODULE_STATE_GOING:
839 return sprintf(buffer, "%s\n", state);
842 static struct module_attribute initstate = {
843 .attr = { .name = "initstate", .mode = 0444 },
844 .show = show_initstate,
847 static struct module_attribute *modinfo_attrs[] = {
851 #ifdef CONFIG_MODULE_UNLOAD
857 static const char vermagic[] = VERMAGIC_STRING;
859 #ifdef CONFIG_MODVERSIONS
860 static int check_version(Elf_Shdr *sechdrs,
861 unsigned int versindex,
864 const unsigned long *crc)
866 unsigned int i, num_versions;
867 struct modversion_info *versions;
869 /* Exporting module didn't supply crcs? OK, we're already tainted. */
873 versions = (void *) sechdrs[versindex].sh_addr;
874 num_versions = sechdrs[versindex].sh_size
875 / sizeof(struct modversion_info);
877 for (i = 0; i < num_versions; i++) {
878 if (strcmp(versions[i].name, symname) != 0)
881 if (versions[i].crc == *crc)
883 printk("%s: disagrees about version of symbol %s\n",
885 DEBUGP("Found checksum %lX vs module %lX\n",
886 *crc, versions[i].crc);
889 /* Not in module's version table. OK, but that taints the kernel. */
890 if (!(tainted & TAINT_FORCED_MODULE))
891 printk("%s: no version for \"%s\" found: kernel tainted.\n",
893 add_taint_module(mod, TAINT_FORCED_MODULE);
897 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
898 unsigned int versindex,
901 const unsigned long *crc;
902 struct module *owner;
904 if (!__find_symbol("struct_module", &owner, &crc, 1))
906 return check_version(sechdrs, versindex, "struct_module", mod,
910 /* First part is kernel version, which we ignore. */
911 static inline int same_magic(const char *amagic, const char *bmagic)
913 amagic += strcspn(amagic, " ");
914 bmagic += strcspn(bmagic, " ");
915 return strcmp(amagic, bmagic) == 0;
918 static inline int check_version(Elf_Shdr *sechdrs,
919 unsigned int versindex,
922 const unsigned long *crc)
927 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
928 unsigned int versindex,
934 static inline int same_magic(const char *amagic, const char *bmagic)
936 return strcmp(amagic, bmagic) == 0;
938 #endif /* CONFIG_MODVERSIONS */
940 /* Resolve a symbol for this module. I.e. if we find one, record usage.
941 Must be holding module_mutex. */
942 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
943 unsigned int versindex,
947 struct module *owner;
949 const unsigned long *crc;
951 ret = __find_symbol(name, &owner, &crc,
952 !(mod->taints & TAINT_PROPRIETARY_MODULE));
954 /* use_module can fail due to OOM,
955 or module initialization or unloading */
956 if (!check_version(sechdrs, versindex, name, mod, crc) ||
957 !use_module(mod, owner))
965 * /sys/module/foo/sections stuff
966 * J. Corbet <corbet@lwn.net>
968 #ifdef CONFIG_KALLSYMS
969 static ssize_t module_sect_show(struct module_attribute *mattr,
970 struct module *mod, char *buf)
972 struct module_sect_attr *sattr =
973 container_of(mattr, struct module_sect_attr, mattr);
974 return sprintf(buf, "0x%lx\n", sattr->address);
977 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
981 for (section = 0; section < sect_attrs->nsections; section++)
982 kfree(sect_attrs->attrs[section].name);
986 static void add_sect_attrs(struct module *mod, unsigned int nsect,
987 char *secstrings, Elf_Shdr *sechdrs)
989 unsigned int nloaded = 0, i, size[2];
990 struct module_sect_attrs *sect_attrs;
991 struct module_sect_attr *sattr;
992 struct attribute **gattr;
994 /* Count loaded sections and allocate structures */
995 for (i = 0; i < nsect; i++)
996 if (sechdrs[i].sh_flags & SHF_ALLOC)
998 size[0] = ALIGN(sizeof(*sect_attrs)
999 + nloaded * sizeof(sect_attrs->attrs[0]),
1000 sizeof(sect_attrs->grp.attrs[0]));
1001 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1002 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1003 if (sect_attrs == NULL)
1006 /* Setup section attributes. */
1007 sect_attrs->grp.name = "sections";
1008 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1010 sect_attrs->nsections = 0;
1011 sattr = §_attrs->attrs[0];
1012 gattr = §_attrs->grp.attrs[0];
1013 for (i = 0; i < nsect; i++) {
1014 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1016 sattr->address = sechdrs[i].sh_addr;
1017 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1019 if (sattr->name == NULL)
1021 sect_attrs->nsections++;
1022 sattr->mattr.show = module_sect_show;
1023 sattr->mattr.store = NULL;
1024 sattr->mattr.attr.name = sattr->name;
1025 sattr->mattr.attr.mode = S_IRUGO;
1026 *(gattr++) = &(sattr++)->mattr.attr;
1030 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1033 mod->sect_attrs = sect_attrs;
1036 free_sect_attrs(sect_attrs);
1039 static void remove_sect_attrs(struct module *mod)
1041 if (mod->sect_attrs) {
1042 sysfs_remove_group(&mod->mkobj.kobj,
1043 &mod->sect_attrs->grp);
1044 /* We are positive that no one is using any sect attrs
1045 * at this point. Deallocate immediately. */
1046 free_sect_attrs(mod->sect_attrs);
1047 mod->sect_attrs = NULL;
1052 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1055 struct module_notes_attrs {
1056 struct kobject *dir;
1058 struct bin_attribute attrs[0];
1061 static ssize_t module_notes_read(struct kobject *kobj,
1062 struct bin_attribute *bin_attr,
1063 char *buf, loff_t pos, size_t count)
1066 * The caller checked the pos and count against our size.
1068 memcpy(buf, bin_attr->private + pos, count);
1072 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1075 if (notes_attrs->dir) {
1077 sysfs_remove_bin_file(notes_attrs->dir,
1078 ¬es_attrs->attrs[i]);
1079 kobject_del(notes_attrs->dir);
1084 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1085 char *secstrings, Elf_Shdr *sechdrs)
1087 unsigned int notes, loaded, i;
1088 struct module_notes_attrs *notes_attrs;
1089 struct bin_attribute *nattr;
1091 /* Count notes sections and allocate structures. */
1093 for (i = 0; i < nsect; i++)
1094 if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
1095 (sechdrs[i].sh_type == SHT_NOTE))
1101 notes_attrs = kzalloc(sizeof(*notes_attrs)
1102 + notes * sizeof(notes_attrs->attrs[0]),
1104 if (notes_attrs == NULL)
1107 notes_attrs->notes = notes;
1108 nattr = ¬es_attrs->attrs[0];
1109 for (loaded = i = 0; i < nsect; ++i) {
1110 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1112 if (sechdrs[i].sh_type == SHT_NOTE) {
1113 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1114 nattr->attr.mode = S_IRUGO;
1115 nattr->size = sechdrs[i].sh_size;
1116 nattr->private = (void *) sechdrs[i].sh_addr;
1117 nattr->read = module_notes_read;
1123 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1124 if (!notes_attrs->dir)
1127 for (i = 0; i < notes; ++i)
1128 if (sysfs_create_bin_file(notes_attrs->dir,
1129 ¬es_attrs->attrs[i]))
1132 mod->notes_attrs = notes_attrs;
1136 free_notes_attrs(notes_attrs, i);
1139 static void remove_notes_attrs(struct module *mod)
1141 if (mod->notes_attrs)
1142 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1147 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1148 char *sectstrings, Elf_Shdr *sechdrs)
1152 static inline void remove_sect_attrs(struct module *mod)
1156 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1157 char *sectstrings, Elf_Shdr *sechdrs)
1161 static inline void remove_notes_attrs(struct module *mod)
1164 #endif /* CONFIG_KALLSYMS */
1167 int module_add_modinfo_attrs(struct module *mod)
1169 struct module_attribute *attr;
1170 struct module_attribute *temp_attr;
1174 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1175 (ARRAY_SIZE(modinfo_attrs) + 1)),
1177 if (!mod->modinfo_attrs)
1180 temp_attr = mod->modinfo_attrs;
1181 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1183 (attr->test && attr->test(mod))) {
1184 memcpy(temp_attr, attr, sizeof(*temp_attr));
1185 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1192 void module_remove_modinfo_attrs(struct module *mod)
1194 struct module_attribute *attr;
1197 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1198 /* pick a field to test for end of list */
1199 if (!attr->attr.name)
1201 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1205 kfree(mod->modinfo_attrs);
1210 int mod_sysfs_init(struct module *mod)
1214 if (!module_sysfs_initialized) {
1215 printk(KERN_ERR "%s: module sysfs not initialized\n",
1220 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1221 err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name);
1224 mod->mkobj.kobj.kset = module_kset;
1225 mod->mkobj.kobj.ktype = &module_ktype;
1226 mod->mkobj.mod = mod;
1228 kobject_init(&mod->mkobj.kobj);
1234 int mod_sysfs_setup(struct module *mod,
1235 struct kernel_param *kparam,
1236 unsigned int num_params)
1240 /* delay uevent until full sysfs population */
1241 err = kobject_add(&mod->mkobj.kobj);
1245 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1246 if (!mod->holders_dir) {
1251 err = module_param_sysfs_setup(mod, kparam, num_params);
1253 goto out_unreg_holders;
1255 err = module_add_modinfo_attrs(mod);
1257 goto out_unreg_param;
1259 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1263 module_param_sysfs_remove(mod);
1265 kobject_unregister(mod->holders_dir);
1267 kobject_del(&mod->mkobj.kobj);
1268 kobject_put(&mod->mkobj.kobj);
1274 static void mod_kobject_remove(struct module *mod)
1276 module_remove_modinfo_attrs(mod);
1277 module_param_sysfs_remove(mod);
1278 kobject_unregister(mod->mkobj.drivers_dir);
1279 kobject_unregister(mod->holders_dir);
1280 kobject_unregister(&mod->mkobj.kobj);
1284 * unlink the module with the whole machine is stopped with interrupts off
1285 * - this defends against kallsyms not taking locks
1287 static int __unlink_module(void *_mod)
1289 struct module *mod = _mod;
1290 list_del(&mod->list);
1294 /* Free a module, remove from lists, etc (must hold module_mutex). */
1295 static void free_module(struct module *mod)
1297 /* Delete from various lists */
1298 stop_machine_run(__unlink_module, mod, NR_CPUS);
1299 remove_notes_attrs(mod);
1300 remove_sect_attrs(mod);
1301 mod_kobject_remove(mod);
1303 unwind_remove_table(mod->unwind_info, 0);
1305 /* Arch-specific cleanup. */
1306 module_arch_cleanup(mod);
1308 /* Module unload stuff */
1309 module_unload_free(mod);
1311 /* This may be NULL, but that's OK */
1312 module_free(mod, mod->module_init);
1315 percpu_modfree(mod->percpu);
1317 /* Free lock-classes: */
1318 lockdep_free_key_range(mod->module_core, mod->core_size);
1320 /* Finally, free the core (containing the module structure) */
1321 module_free(mod, mod->module_core);
1324 void *__symbol_get(const char *symbol)
1326 struct module *owner;
1327 unsigned long value;
1328 const unsigned long *crc;
1331 value = __find_symbol(symbol, &owner, &crc, 1);
1332 if (value && !strong_try_module_get(owner))
1336 return (void *)value;
1338 EXPORT_SYMBOL_GPL(__symbol_get);
1341 * Ensure that an exported symbol [global namespace] does not already exist
1342 * in the kernel or in some other module's exported symbol table.
1344 static int verify_export_symbols(struct module *mod)
1346 const char *name = NULL;
1347 unsigned long i, ret = 0;
1348 struct module *owner;
1349 const unsigned long *crc;
1351 for (i = 0; i < mod->num_syms; i++)
1352 if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) {
1353 name = mod->syms[i].name;
1358 for (i = 0; i < mod->num_gpl_syms; i++)
1359 if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) {
1360 name = mod->gpl_syms[i].name;
1367 printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
1368 mod->name, name, module_name(owner));
1373 /* Change all symbols so that st_value encodes the pointer directly. */
1374 static int simplify_symbols(Elf_Shdr *sechdrs,
1375 unsigned int symindex,
1377 unsigned int versindex,
1378 unsigned int pcpuindex,
1381 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1382 unsigned long secbase;
1383 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1386 for (i = 1; i < n; i++) {
1387 switch (sym[i].st_shndx) {
1389 /* We compiled with -fno-common. These are not
1390 supposed to happen. */
1391 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1392 printk("%s: please compile with -fno-common\n",
1398 /* Don't need to do anything */
1399 DEBUGP("Absolute symbol: 0x%08lx\n",
1400 (long)sym[i].st_value);
1405 = resolve_symbol(sechdrs, versindex,
1406 strtab + sym[i].st_name, mod);
1408 /* Ok if resolved. */
1409 if (sym[i].st_value != 0)
1412 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1415 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1416 mod->name, strtab + sym[i].st_name);
1421 /* Divert to percpu allocation if a percpu var. */
1422 if (sym[i].st_shndx == pcpuindex)
1423 secbase = (unsigned long)mod->percpu;
1425 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1426 sym[i].st_value += secbase;
1434 /* Update size with this section: return offset. */
1435 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
1439 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1440 *size = ret + sechdr->sh_size;
1444 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1445 might -- code, read-only data, read-write data, small data. Tally
1446 sizes, and place the offsets into sh_entsize fields: high bit means it
1448 static void layout_sections(struct module *mod,
1449 const Elf_Ehdr *hdr,
1451 const char *secstrings)
1453 static unsigned long const masks[][2] = {
1454 /* NOTE: all executable code must be the first section
1455 * in this array; otherwise modify the text_size
1456 * finder in the two loops below */
1457 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1458 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1459 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1460 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1464 for (i = 0; i < hdr->e_shnum; i++)
1465 sechdrs[i].sh_entsize = ~0UL;
1467 DEBUGP("Core section allocation order:\n");
1468 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1469 for (i = 0; i < hdr->e_shnum; ++i) {
1470 Elf_Shdr *s = &sechdrs[i];
1472 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1473 || (s->sh_flags & masks[m][1])
1474 || s->sh_entsize != ~0UL
1475 || strncmp(secstrings + s->sh_name,
1478 s->sh_entsize = get_offset(&mod->core_size, s);
1479 DEBUGP("\t%s\n", secstrings + s->sh_name);
1482 mod->core_text_size = mod->core_size;
1485 DEBUGP("Init section allocation order:\n");
1486 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1487 for (i = 0; i < hdr->e_shnum; ++i) {
1488 Elf_Shdr *s = &sechdrs[i];
1490 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1491 || (s->sh_flags & masks[m][1])
1492 || s->sh_entsize != ~0UL
1493 || strncmp(secstrings + s->sh_name,
1496 s->sh_entsize = (get_offset(&mod->init_size, s)
1497 | INIT_OFFSET_MASK);
1498 DEBUGP("\t%s\n", secstrings + s->sh_name);
1501 mod->init_text_size = mod->init_size;
1505 static void set_license(struct module *mod, const char *license)
1508 license = "unspecified";
1510 if (!license_is_gpl_compatible(license)) {
1511 if (!(tainted & TAINT_PROPRIETARY_MODULE))
1512 printk(KERN_WARNING "%s: module license '%s' taints "
1513 "kernel.\n", mod->name, license);
1514 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1518 /* Parse tag=value strings from .modinfo section */
1519 static char *next_string(char *string, unsigned long *secsize)
1521 /* Skip non-zero chars */
1524 if ((*secsize)-- <= 1)
1528 /* Skip any zero padding. */
1529 while (!string[0]) {
1531 if ((*secsize)-- <= 1)
1537 static char *get_modinfo(Elf_Shdr *sechdrs,
1542 unsigned int taglen = strlen(tag);
1543 unsigned long size = sechdrs[info].sh_size;
1545 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1546 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1547 return p + taglen + 1;
1552 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1553 unsigned int infoindex)
1555 struct module_attribute *attr;
1558 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1561 get_modinfo(sechdrs,
1567 #ifdef CONFIG_KALLSYMS
1568 static int is_exported(const char *name, const struct module *mod)
1570 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1573 if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1580 static char elf_type(const Elf_Sym *sym,
1582 const char *secstrings,
1585 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1586 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1591 if (sym->st_shndx == SHN_UNDEF)
1593 if (sym->st_shndx == SHN_ABS)
1595 if (sym->st_shndx >= SHN_LORESERVE)
1597 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1599 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1600 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1601 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1603 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1608 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1609 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1614 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1615 ".debug", strlen(".debug")) == 0)
1620 static void add_kallsyms(struct module *mod,
1622 unsigned int symindex,
1623 unsigned int strindex,
1624 const char *secstrings)
1628 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1629 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1630 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1632 /* Set types up while we still have access to sections. */
1633 for (i = 0; i < mod->num_symtab; i++)
1634 mod->symtab[i].st_info
1635 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1638 static inline void add_kallsyms(struct module *mod,
1640 unsigned int symindex,
1641 unsigned int strindex,
1642 const char *secstrings)
1645 #endif /* CONFIG_KALLSYMS */
1647 /* Allocate and load the module: note that size of section 0 is always
1648 zero, and we rely on this for optional sections. */
1649 static struct module *load_module(void __user *umod,
1651 const char __user *uargs)
1655 char *secstrings, *args, *modmagic, *strtab = NULL;
1657 unsigned int symindex = 0;
1658 unsigned int strindex = 0;
1659 unsigned int setupindex;
1660 unsigned int exindex;
1661 unsigned int exportindex;
1662 unsigned int modindex;
1663 unsigned int obsparmindex;
1664 unsigned int infoindex;
1665 unsigned int gplindex;
1666 unsigned int crcindex;
1667 unsigned int gplcrcindex;
1668 unsigned int versindex;
1669 unsigned int pcpuindex;
1670 unsigned int gplfutureindex;
1671 unsigned int gplfuturecrcindex;
1672 unsigned int unwindex = 0;
1673 unsigned int unusedindex;
1674 unsigned int unusedcrcindex;
1675 unsigned int unusedgplindex;
1676 unsigned int unusedgplcrcindex;
1677 unsigned int markersindex;
1678 unsigned int markersstringsindex;
1681 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1682 struct exception_table_entry *extable;
1683 mm_segment_t old_fs;
1685 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1687 if (len < sizeof(*hdr))
1688 return ERR_PTR(-ENOEXEC);
1690 /* Suck in entire file: we'll want most of it. */
1691 /* vmalloc barfs on "unusual" numbers. Check here */
1692 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1693 return ERR_PTR(-ENOMEM);
1694 if (copy_from_user(hdr, umod, len) != 0) {
1699 /* Sanity checks against insmoding binaries or wrong arch,
1700 weird elf version */
1701 if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
1702 || hdr->e_type != ET_REL
1703 || !elf_check_arch(hdr)
1704 || hdr->e_shentsize != sizeof(*sechdrs)) {
1709 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1712 /* Convenience variables */
1713 sechdrs = (void *)hdr + hdr->e_shoff;
1714 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1715 sechdrs[0].sh_addr = 0;
1717 for (i = 1; i < hdr->e_shnum; i++) {
1718 if (sechdrs[i].sh_type != SHT_NOBITS
1719 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1722 /* Mark all sections sh_addr with their address in the
1724 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1726 /* Internal symbols and strings. */
1727 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1729 strindex = sechdrs[i].sh_link;
1730 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1732 #ifndef CONFIG_MODULE_UNLOAD
1733 /* Don't load .exit sections */
1734 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1735 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1739 modindex = find_sec(hdr, sechdrs, secstrings,
1740 ".gnu.linkonce.this_module");
1742 printk(KERN_WARNING "No module found in object\n");
1746 mod = (void *)sechdrs[modindex].sh_addr;
1748 if (symindex == 0) {
1749 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1755 /* Optional sections */
1756 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1757 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1758 gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1759 unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
1760 unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
1761 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1762 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1763 gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1764 unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
1765 unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
1766 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1767 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1768 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1769 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1770 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1771 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1772 #ifdef ARCH_UNWIND_SECTION_NAME
1773 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1776 /* Don't keep modinfo section */
1777 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1778 #ifdef CONFIG_KALLSYMS
1779 /* Keep symbol and string tables for decoding later. */
1780 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1781 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1784 sechdrs[unwindex].sh_flags |= SHF_ALLOC;
1786 /* Check module struct version now, before we try to use module. */
1787 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1792 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1793 /* This is allowed: modprobe --force will invalidate it. */
1795 add_taint_module(mod, TAINT_FORCED_MODULE);
1796 printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
1798 } else if (!same_magic(modmagic, vermagic)) {
1799 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1800 mod->name, modmagic, vermagic);
1805 /* Now copy in args */
1806 args = strndup_user(uargs, ~0UL >> 1);
1808 err = PTR_ERR(args);
1812 if (find_module(mod->name)) {
1817 mod->state = MODULE_STATE_COMING;
1819 /* Allow arches to frob section contents and sizes. */
1820 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1825 /* We have a special allocation for this section. */
1826 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1827 sechdrs[pcpuindex].sh_addralign,
1833 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1834 mod->percpu = percpu;
1837 /* Determine total sizes, and put offsets in sh_entsize. For now
1838 this is done generically; there doesn't appear to be any
1839 special cases for the architectures. */
1840 layout_sections(mod, hdr, sechdrs, secstrings);
1842 /* Do the allocs. */
1843 ptr = module_alloc(mod->core_size);
1848 memset(ptr, 0, mod->core_size);
1849 mod->module_core = ptr;
1851 ptr = module_alloc(mod->init_size);
1852 if (!ptr && mod->init_size) {
1856 memset(ptr, 0, mod->init_size);
1857 mod->module_init = ptr;
1859 /* Transfer each section which specifies SHF_ALLOC */
1860 DEBUGP("final section addresses:\n");
1861 for (i = 0; i < hdr->e_shnum; i++) {
1864 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1867 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
1868 dest = mod->module_init
1869 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
1871 dest = mod->module_core + sechdrs[i].sh_entsize;
1873 if (sechdrs[i].sh_type != SHT_NOBITS)
1874 memcpy(dest, (void *)sechdrs[i].sh_addr,
1875 sechdrs[i].sh_size);
1876 /* Update sh_addr to point to copy in image. */
1877 sechdrs[i].sh_addr = (unsigned long)dest;
1878 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
1880 /* Module has been moved. */
1881 mod = (void *)sechdrs[modindex].sh_addr;
1883 /* Now we've moved module, initialize linked lists, etc. */
1884 module_unload_init(mod);
1886 /* Initialize kobject, so we can reference it. */
1887 err = mod_sysfs_init(mod);
1891 /* Set up license info based on the info section */
1892 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
1894 if (strcmp(mod->name, "ndiswrapper") == 0)
1895 add_taint(TAINT_PROPRIETARY_MODULE);
1896 if (strcmp(mod->name, "driverloader") == 0)
1897 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1899 /* Set up MODINFO_ATTR fields */
1900 setup_modinfo(mod, sechdrs, infoindex);
1902 /* Fix up syms, so that st_value is a pointer to location. */
1903 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
1908 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
1909 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
1910 mod->syms = (void *)sechdrs[exportindex].sh_addr;
1912 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
1913 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
1914 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
1916 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
1917 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
1918 sizeof(*mod->gpl_future_syms);
1919 mod->num_unused_syms = sechdrs[unusedindex].sh_size /
1920 sizeof(*mod->unused_syms);
1921 mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
1922 sizeof(*mod->unused_gpl_syms);
1923 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
1924 if (gplfuturecrcindex)
1925 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
1927 mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
1929 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
1930 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
1931 if (unusedgplcrcindex)
1932 mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr;
1934 #ifdef CONFIG_MODVERSIONS
1935 if ((mod->num_syms && !crcindex) ||
1936 (mod->num_gpl_syms && !gplcrcindex) ||
1937 (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
1938 (mod->num_unused_syms && !unusedcrcindex) ||
1939 (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
1940 printk(KERN_WARNING "%s: No versions for exported symbols."
1941 " Tainting kernel.\n", mod->name);
1942 add_taint_module(mod, TAINT_FORCED_MODULE);
1945 markersindex = find_sec(hdr, sechdrs, secstrings, "__markers");
1946 markersstringsindex = find_sec(hdr, sechdrs, secstrings,
1947 "__markers_strings");
1949 /* Now do relocations. */
1950 for (i = 1; i < hdr->e_shnum; i++) {
1951 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1952 unsigned int info = sechdrs[i].sh_info;
1954 /* Not a valid relocation section? */
1955 if (info >= hdr->e_shnum)
1958 /* Don't bother with non-allocated sections */
1959 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1962 if (sechdrs[i].sh_type == SHT_REL)
1963 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
1964 else if (sechdrs[i].sh_type == SHT_RELA)
1965 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1970 #ifdef CONFIG_MARKERS
1971 mod->markers = (void *)sechdrs[markersindex].sh_addr;
1973 sechdrs[markersindex].sh_size / sizeof(*mod->markers);
1976 /* Find duplicate symbols */
1977 err = verify_export_symbols(mod);
1982 /* Set up and sort exception table */
1983 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
1984 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
1985 sort_extable(extable, extable + mod->num_exentries);
1987 /* Finally, copy percpu area over. */
1988 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
1989 sechdrs[pcpuindex].sh_size);
1991 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
1993 #ifdef CONFIG_MARKERS
1995 marker_update_probe_range(mod->markers,
1996 mod->markers + mod->num_markers, NULL, NULL);
1998 err = module_finalize(hdr, sechdrs, mod);
2002 /* flush the icache in correct context */
2007 * Flush the instruction cache, since we've played with text.
2008 * Do it before processing of module parameters, so the module
2009 * can provide parameter accessor functions of its own.
2011 if (mod->module_init)
2012 flush_icache_range((unsigned long)mod->module_init,
2013 (unsigned long)mod->module_init
2015 flush_icache_range((unsigned long)mod->module_core,
2016 (unsigned long)mod->module_core + mod->core_size);
2022 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2025 /* Size of section 0 is 0, so this works well if no params */
2026 err = parse_args(mod->name, mod->args,
2027 (struct kernel_param *)
2028 sechdrs[setupindex].sh_addr,
2029 sechdrs[setupindex].sh_size
2030 / sizeof(struct kernel_param),
2035 err = mod_sysfs_setup(mod,
2036 (struct kernel_param *)
2037 sechdrs[setupindex].sh_addr,
2038 sechdrs[setupindex].sh_size
2039 / sizeof(struct kernel_param));
2042 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2043 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2045 /* Size of section 0 is 0, so this works well if no unwind info. */
2046 mod->unwind_info = unwind_add_table(mod,
2047 (void *)sechdrs[unwindex].sh_addr,
2048 sechdrs[unwindex].sh_size);
2050 /* Get rid of temporary copy */
2057 module_arch_cleanup(mod);
2059 module_unload_free(mod);
2060 module_free(mod, mod->module_init);
2062 module_free(mod, mod->module_core);
2065 percpu_modfree(percpu);
2070 return ERR_PTR(err);
2073 printk(KERN_ERR "Module len %lu truncated\n", len);
2079 * link the module with the whole machine is stopped with interrupts off
2080 * - this defends against kallsyms not taking locks
2082 static int __link_module(void *_mod)
2084 struct module *mod = _mod;
2085 list_add(&mod->list, &modules);
2089 /* This is where the real work happens */
2091 sys_init_module(void __user *umod,
2093 const char __user *uargs)
2098 /* Must have permission */
2099 if (!capable(CAP_SYS_MODULE))
2102 /* Only one module load at a time, please */
2103 if (mutex_lock_interruptible(&module_mutex) != 0)
2106 /* Do all the hard work */
2107 mod = load_module(umod, len, uargs);
2109 mutex_unlock(&module_mutex);
2110 return PTR_ERR(mod);
2113 /* Now sew it into the lists. They won't access us, since
2114 strong_try_module_get() will fail. */
2115 stop_machine_run(__link_module, mod, NR_CPUS);
2117 /* Drop lock so they can recurse */
2118 mutex_unlock(&module_mutex);
2120 blocking_notifier_call_chain(&module_notify_list,
2121 MODULE_STATE_COMING, mod);
2123 /* Start the module */
2124 if (mod->init != NULL)
2127 /* Init routine failed: abort. Try to protect us from
2128 buggy refcounters. */
2129 mod->state = MODULE_STATE_GOING;
2130 synchronize_sched();
2132 mutex_lock(&module_mutex);
2134 mutex_unlock(&module_mutex);
2138 /* Now it's a first class citizen! */
2139 mutex_lock(&module_mutex);
2140 mod->state = MODULE_STATE_LIVE;
2141 /* Drop initial reference. */
2143 unwind_remove_table(mod->unwind_info, 1);
2144 module_free(mod, mod->module_init);
2145 mod->module_init = NULL;
2147 mod->init_text_size = 0;
2148 mutex_unlock(&module_mutex);
2153 static inline int within(unsigned long addr, void *start, unsigned long size)
2155 return ((void *)addr >= start && (void *)addr < start + size);
2158 #ifdef CONFIG_KALLSYMS
2160 * This ignores the intensely annoying "mapping symbols" found
2161 * in ARM ELF files: $a, $t and $d.
2163 static inline int is_arm_mapping_symbol(const char *str)
2165 return str[0] == '$' && strchr("atd", str[1])
2166 && (str[2] == '\0' || str[2] == '.');
2169 static const char *get_ksymbol(struct module *mod,
2171 unsigned long *size,
2172 unsigned long *offset)
2174 unsigned int i, best = 0;
2175 unsigned long nextval;
2177 /* At worse, next value is at end of module */
2178 if (within(addr, mod->module_init, mod->init_size))
2179 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2181 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2183 /* Scan for closest preceeding symbol, and next symbol. (ELF
2184 starts real symbols at 1). */
2185 for (i = 1; i < mod->num_symtab; i++) {
2186 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2189 /* We ignore unnamed symbols: they're uninformative
2190 * and inserted at a whim. */
2191 if (mod->symtab[i].st_value <= addr
2192 && mod->symtab[i].st_value > mod->symtab[best].st_value
2193 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2194 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2196 if (mod->symtab[i].st_value > addr
2197 && mod->symtab[i].st_value < nextval
2198 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2199 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2200 nextval = mod->symtab[i].st_value;
2207 *size = nextval - mod->symtab[best].st_value;
2209 *offset = addr - mod->symtab[best].st_value;
2210 return mod->strtab + mod->symtab[best].st_name;
2213 /* For kallsyms to ask for address resolution. NULL means not found.
2214 We don't lock, as this is used for oops resolution and races are a
2216 /* FIXME: Risky: returns a pointer into a module w/o lock */
2217 const char *module_address_lookup(unsigned long addr,
2218 unsigned long *size,
2219 unsigned long *offset,
2223 const char *ret = NULL;
2226 list_for_each_entry(mod, &modules, list) {
2227 if (within(addr, mod->module_init, mod->init_size)
2228 || within(addr, mod->module_core, mod->core_size)) {
2230 *modname = mod->name;
2231 ret = get_ksymbol(mod, addr, size, offset);
2239 int lookup_module_symbol_name(unsigned long addr, char *symname)
2244 list_for_each_entry(mod, &modules, list) {
2245 if (within(addr, mod->module_init, mod->init_size) ||
2246 within(addr, mod->module_core, mod->core_size)) {
2249 sym = get_ksymbol(mod, addr, NULL, NULL);
2252 strlcpy(symname, sym, KSYM_NAME_LEN);
2262 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2263 unsigned long *offset, char *modname, char *name)
2268 list_for_each_entry(mod, &modules, list) {
2269 if (within(addr, mod->module_init, mod->init_size) ||
2270 within(addr, mod->module_core, mod->core_size)) {
2273 sym = get_ksymbol(mod, addr, size, offset);
2277 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2279 strlcpy(name, sym, KSYM_NAME_LEN);
2289 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2290 char *name, char *module_name, int *exported)
2295 list_for_each_entry(mod, &modules, list) {
2296 if (symnum < mod->num_symtab) {
2297 *value = mod->symtab[symnum].st_value;
2298 *type = mod->symtab[symnum].st_info;
2299 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2301 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2302 *exported = is_exported(name, mod);
2306 symnum -= mod->num_symtab;
2312 static unsigned long mod_find_symname(struct module *mod, const char *name)
2316 for (i = 0; i < mod->num_symtab; i++)
2317 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2318 mod->symtab[i].st_info != 'U')
2319 return mod->symtab[i].st_value;
2323 /* Look for this name: can be of form module:name. */
2324 unsigned long module_kallsyms_lookup_name(const char *name)
2328 unsigned long ret = 0;
2330 /* Don't lock: we're in enough trouble already. */
2332 if ((colon = strchr(name, ':')) != NULL) {
2334 if ((mod = find_module(name)) != NULL)
2335 ret = mod_find_symname(mod, colon+1);
2338 list_for_each_entry(mod, &modules, list)
2339 if ((ret = mod_find_symname(mod, name)) != 0)
2345 #endif /* CONFIG_KALLSYMS */
2347 /* Called by the /proc file system to return a list of modules. */
2348 static void *m_start(struct seq_file *m, loff_t *pos)
2350 mutex_lock(&module_mutex);
2351 return seq_list_start(&modules, *pos);
2354 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2356 return seq_list_next(p, &modules, pos);
2359 static void m_stop(struct seq_file *m, void *p)
2361 mutex_unlock(&module_mutex);
2364 static char *taint_flags(unsigned int taints, char *buf)
2370 if (taints & TAINT_PROPRIETARY_MODULE)
2372 if (taints & TAINT_FORCED_MODULE)
2375 * TAINT_FORCED_RMMOD: could be added.
2376 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2386 static int m_show(struct seq_file *m, void *p)
2388 struct module *mod = list_entry(p, struct module, list);
2391 seq_printf(m, "%s %lu",
2392 mod->name, mod->init_size + mod->core_size);
2393 print_unload_info(m, mod);
2395 /* Informative for users. */
2396 seq_printf(m, " %s",
2397 mod->state == MODULE_STATE_GOING ? "Unloading":
2398 mod->state == MODULE_STATE_COMING ? "Loading":
2400 /* Used by oprofile and other similar tools. */
2401 seq_printf(m, " 0x%p", mod->module_core);
2405 seq_printf(m, " %s", taint_flags(mod->taints, buf));
2407 seq_printf(m, "\n");
2411 /* Format: modulename size refcount deps address
2413 Where refcount is a number or -, and deps is a comma-separated list
2416 const struct seq_operations modules_op = {
2423 /* Given an address, look for it in the module exception tables. */
2424 const struct exception_table_entry *search_module_extables(unsigned long addr)
2426 const struct exception_table_entry *e = NULL;
2430 list_for_each_entry(mod, &modules, list) {
2431 if (mod->num_exentries == 0)
2434 e = search_extable(mod->extable,
2435 mod->extable + mod->num_exentries - 1,
2442 /* Now, if we found one, we are running inside it now, hence
2443 we cannot unload the module, hence no refcnt needed. */
2448 * Is this a valid module address?
2450 int is_module_address(unsigned long addr)
2456 list_for_each_entry(mod, &modules, list) {
2457 if (within(addr, mod->module_core, mod->core_size)) {
2469 /* Is this a valid kernel address? */
2470 struct module *__module_text_address(unsigned long addr)
2474 list_for_each_entry(mod, &modules, list)
2475 if (within(addr, mod->module_init, mod->init_text_size)
2476 || within(addr, mod->module_core, mod->core_text_size))
2481 struct module *module_text_address(unsigned long addr)
2486 mod = __module_text_address(addr);
2492 /* Don't grab lock, we're oopsing. */
2493 void print_modules(void)
2498 printk("Modules linked in:");
2499 list_for_each_entry(mod, &modules, list)
2500 printk(" %s%s", mod->name, taint_flags(mod->taints, buf));
2505 static char *make_driver_name(struct device_driver *drv)
2509 driver_name = kmalloc(strlen(drv->name) + strlen(drv->bus->name) + 2,
2514 sprintf(driver_name, "%s:%s", drv->bus->name, drv->name);
2518 static void module_create_drivers_dir(struct module_kobject *mk)
2520 if (!mk || mk->drivers_dir)
2523 mk->drivers_dir = kobject_create_and_add("drivers", &mk->kobj);
2526 void module_add_driver(struct module *mod, struct device_driver *drv)
2530 struct module_kobject *mk = NULL;
2537 else if (drv->mod_name) {
2538 struct kobject *mkobj;
2540 /* Lookup built-in module entry in /sys/modules */
2541 mkobj = kset_find_obj(module_kset, drv->mod_name);
2543 mk = container_of(mkobj, struct module_kobject, kobj);
2544 /* remember our module structure */
2546 /* kset_find_obj took a reference */
2554 /* Don't check return codes; these calls are idempotent */
2555 no_warn = sysfs_create_link(&drv->kobj, &mk->kobj, "module");
2556 driver_name = make_driver_name(drv);
2558 module_create_drivers_dir(mk);
2559 no_warn = sysfs_create_link(mk->drivers_dir, &drv->kobj,
2564 EXPORT_SYMBOL(module_add_driver);
2566 void module_remove_driver(struct device_driver *drv)
2568 struct module_kobject *mk = NULL;
2574 sysfs_remove_link(&drv->kobj, "module");
2577 mk = &drv->owner->mkobj;
2578 else if (drv->mkobj)
2580 if (mk && mk->drivers_dir) {
2581 driver_name = make_driver_name(drv);
2583 sysfs_remove_link(mk->drivers_dir, driver_name);
2588 EXPORT_SYMBOL(module_remove_driver);
2591 #ifdef CONFIG_MODVERSIONS
2592 /* Generate the signature for struct module here, too, for modversions. */
2593 void struct_module(struct module *mod) { return; }
2594 EXPORT_SYMBOL(struct_module);
2597 #ifdef CONFIG_MARKERS
2598 void module_update_markers(struct module *probe_module, int *refcount)
2602 mutex_lock(&module_mutex);
2603 list_for_each_entry(mod, &modules, list)
2605 marker_update_probe_range(mod->markers,
2606 mod->markers + mod->num_markers,
2607 probe_module, refcount);
2608 mutex_unlock(&module_mutex);