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/cacheflush.h>
47 #include <linux/license.h>
48 #include <asm/sections.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 /* Waiting for a module to finish initializing? */
69 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
71 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
73 int register_module_notifier(struct notifier_block * nb)
75 return blocking_notifier_chain_register(&module_notify_list, nb);
77 EXPORT_SYMBOL(register_module_notifier);
79 int unregister_module_notifier(struct notifier_block * nb)
81 return blocking_notifier_chain_unregister(&module_notify_list, nb);
83 EXPORT_SYMBOL(unregister_module_notifier);
85 /* We require a truly strong try_module_get(): 0 means failure due to
86 ongoing or failed initialization etc. */
87 static inline int strong_try_module_get(struct module *mod)
89 if (mod && mod->state == MODULE_STATE_COMING)
91 if (try_module_get(mod))
97 static inline void add_taint_module(struct module *mod, unsigned flag)
104 * A thread that wants to hold a reference to a module only while it
105 * is running can call this to safely exit. nfsd and lockd use this.
107 void __module_put_and_exit(struct module *mod, long code)
112 EXPORT_SYMBOL(__module_put_and_exit);
114 /* Find a module section: 0 means not found. */
115 static unsigned int find_sec(Elf_Ehdr *hdr,
117 const char *secstrings,
122 for (i = 1; i < hdr->e_shnum; i++)
123 /* Alloc bit cleared means "ignore it." */
124 if ((sechdrs[i].sh_flags & SHF_ALLOC)
125 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
130 /* Provided by the linker */
131 extern const struct kernel_symbol __start___ksymtab[];
132 extern const struct kernel_symbol __stop___ksymtab[];
133 extern const struct kernel_symbol __start___ksymtab_gpl[];
134 extern const struct kernel_symbol __stop___ksymtab_gpl[];
135 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
136 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
137 extern const struct kernel_symbol __start___ksymtab_unused[];
138 extern const struct kernel_symbol __stop___ksymtab_unused[];
139 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
140 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
141 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
142 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
143 extern const unsigned long __start___kcrctab[];
144 extern const unsigned long __start___kcrctab_gpl[];
145 extern const unsigned long __start___kcrctab_gpl_future[];
146 extern const unsigned long __start___kcrctab_unused[];
147 extern const unsigned long __start___kcrctab_unused_gpl[];
149 #ifndef CONFIG_MODVERSIONS
150 #define symversion(base, idx) NULL
152 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
155 /* lookup symbol in given range of kernel_symbols */
156 static const struct kernel_symbol *lookup_symbol(const char *name,
157 const struct kernel_symbol *start,
158 const struct kernel_symbol *stop)
160 const struct kernel_symbol *ks = start;
161 for (; ks < stop; ks++)
162 if (strcmp(ks->name, name) == 0)
167 static bool always_ok(bool gplok, bool warn, const char *name)
172 static bool printk_unused_warning(bool gplok, bool warn, const char *name)
175 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
176 "however this module is using it.\n", name);
178 "This symbol will go away in the future.\n");
180 "Please evalute if this is the right api to use and if "
181 "it really is, submit a report the linux kernel "
182 "mailinglist together with submitting your code for "
188 static bool gpl_only_unused_warning(bool gplok, bool warn, const char *name)
192 return printk_unused_warning(gplok, warn, name);
195 static bool gpl_only(bool gplok, bool warn, const char *name)
200 static bool warn_if_not_gpl(bool gplok, bool warn, const char *name)
202 if (!gplok && warn) {
203 printk(KERN_WARNING "Symbol %s is being used "
204 "by a non-GPL module, which will not "
205 "be allowed in the future\n", name);
206 printk(KERN_WARNING "Please see the file "
207 "Documentation/feature-removal-schedule.txt "
208 "in the kernel source tree for more details.\n");
214 const struct kernel_symbol *start, *stop;
215 const unsigned long *crcs;
216 bool (*check)(bool gplok, bool warn, const char *name);
219 /* Look through this array of symbol tables for a symbol match which
220 * passes the check function. */
221 static const struct kernel_symbol *search_symarrays(const struct symsearch *arr,
226 const unsigned long **crc)
229 const struct kernel_symbol *ks;
231 for (i = 0; i < num; i++) {
232 ks = lookup_symbol(name, arr[i].start, arr[i].stop);
233 if (!ks || !arr[i].check(gplok, warn, name))
237 *crc = symversion(arr[i].crcs, ks - arr[i].start);
243 /* Find a symbol, return value, (optional) crc and (optional) module
245 static unsigned long find_symbol(const char *name,
246 struct module **owner,
247 const unsigned long **crc,
252 const struct kernel_symbol *ks;
253 const struct symsearch arr[] = {
254 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
256 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
257 __start___kcrctab_gpl, gpl_only },
258 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
259 __start___kcrctab_gpl_future, warn_if_not_gpl },
260 { __start___ksymtab_unused, __stop___ksymtab_unused,
261 __start___kcrctab_unused, printk_unused_warning },
262 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
263 __start___kcrctab_unused_gpl, gpl_only_unused_warning },
266 /* Core kernel first. */
267 ks = search_symarrays(arr, ARRAY_SIZE(arr), name, gplok, warn, crc);
274 /* Now try modules. */
275 list_for_each_entry(mod, &modules, list) {
276 struct symsearch arr[] = {
277 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
279 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
280 mod->gpl_crcs, gpl_only },
281 { mod->gpl_future_syms,
282 mod->gpl_future_syms + mod->num_gpl_future_syms,
283 mod->gpl_future_crcs, warn_if_not_gpl },
285 mod->unused_syms + mod->num_unused_syms,
286 mod->unused_crcs, printk_unused_warning },
287 { mod->unused_gpl_syms,
288 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
289 mod->unused_gpl_crcs, gpl_only_unused_warning },
292 ks = search_symarrays(arr, ARRAY_SIZE(arr),
293 name, gplok, warn, crc);
301 DEBUGP("Failed to find symbol %s\n", name);
305 /* Search for module by name: must hold module_mutex. */
306 static struct module *find_module(const char *name)
310 list_for_each_entry(mod, &modules, list) {
311 if (strcmp(mod->name, name) == 0)
318 /* Number of blocks used and allocated. */
319 static unsigned int pcpu_num_used, pcpu_num_allocated;
320 /* Size of each block. -ve means used. */
321 static int *pcpu_size;
323 static int split_block(unsigned int i, unsigned short size)
325 /* Reallocation required? */
326 if (pcpu_num_used + 1 > pcpu_num_allocated) {
329 new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2,
334 pcpu_num_allocated *= 2;
338 /* Insert a new subblock */
339 memmove(&pcpu_size[i+1], &pcpu_size[i],
340 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
343 pcpu_size[i+1] -= size;
348 static inline unsigned int block_size(int val)
355 static void *percpu_modalloc(unsigned long size, unsigned long align,
362 if (align > PAGE_SIZE) {
363 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
364 name, align, PAGE_SIZE);
368 ptr = __per_cpu_start;
369 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
370 /* Extra for alignment requirement. */
371 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
372 BUG_ON(i == 0 && extra != 0);
374 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
377 /* Transfer extra to previous block. */
378 if (pcpu_size[i-1] < 0)
379 pcpu_size[i-1] -= extra;
381 pcpu_size[i-1] += extra;
382 pcpu_size[i] -= extra;
385 /* Split block if warranted */
386 if (pcpu_size[i] - size > sizeof(unsigned long))
387 if (!split_block(i, size))
391 pcpu_size[i] = -pcpu_size[i];
395 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
400 static void percpu_modfree(void *freeme)
403 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
405 /* First entry is core kernel percpu data. */
406 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
408 pcpu_size[i] = -pcpu_size[i];
415 /* Merge with previous? */
416 if (pcpu_size[i-1] >= 0) {
417 pcpu_size[i-1] += pcpu_size[i];
419 memmove(&pcpu_size[i], &pcpu_size[i+1],
420 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
423 /* Merge with next? */
424 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
425 pcpu_size[i] += pcpu_size[i+1];
427 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
428 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
432 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
434 const char *secstrings)
436 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
439 static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
443 for_each_possible_cpu(cpu)
444 memcpy(pcpudest + per_cpu_offset(cpu), from, size);
447 static int percpu_modinit(void)
450 pcpu_num_allocated = 2;
451 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
453 /* Static in-kernel percpu data (used). */
454 pcpu_size[0] = -(__per_cpu_end-__per_cpu_start);
456 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
457 if (pcpu_size[1] < 0) {
458 printk(KERN_ERR "No per-cpu room for modules.\n");
464 __initcall(percpu_modinit);
465 #else /* ... !CONFIG_SMP */
466 static inline void *percpu_modalloc(unsigned long size, unsigned long align,
471 static inline void percpu_modfree(void *pcpuptr)
475 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
477 const char *secstrings)
481 static inline void percpu_modcopy(void *pcpudst, const void *src,
484 /* pcpusec should be 0, and size of that section should be 0. */
487 #endif /* CONFIG_SMP */
489 #define MODINFO_ATTR(field) \
490 static void setup_modinfo_##field(struct module *mod, const char *s) \
492 mod->field = kstrdup(s, GFP_KERNEL); \
494 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
495 struct module *mod, char *buffer) \
497 return sprintf(buffer, "%s\n", mod->field); \
499 static int modinfo_##field##_exists(struct module *mod) \
501 return mod->field != NULL; \
503 static void free_modinfo_##field(struct module *mod) \
508 static struct module_attribute modinfo_##field = { \
509 .attr = { .name = __stringify(field), .mode = 0444 }, \
510 .show = show_modinfo_##field, \
511 .setup = setup_modinfo_##field, \
512 .test = modinfo_##field##_exists, \
513 .free = free_modinfo_##field, \
516 MODINFO_ATTR(version);
517 MODINFO_ATTR(srcversion);
519 static char last_unloaded_module[MODULE_NAME_LEN+1];
521 #ifdef CONFIG_MODULE_UNLOAD
522 /* Init the unload section of the module. */
523 static void module_unload_init(struct module *mod)
527 INIT_LIST_HEAD(&mod->modules_which_use_me);
528 for (i = 0; i < NR_CPUS; i++)
529 local_set(&mod->ref[i].count, 0);
530 /* Hold reference count during initialization. */
531 local_set(&mod->ref[raw_smp_processor_id()].count, 1);
532 /* Backwards compatibility macros put refcount during init. */
533 mod->waiter = current;
536 /* modules using other modules */
539 struct list_head list;
540 struct module *module_which_uses;
543 /* Does a already use b? */
544 static int already_uses(struct module *a, struct module *b)
546 struct module_use *use;
548 list_for_each_entry(use, &b->modules_which_use_me, list) {
549 if (use->module_which_uses == a) {
550 DEBUGP("%s uses %s!\n", a->name, b->name);
554 DEBUGP("%s does not use %s!\n", a->name, b->name);
558 /* Module a uses b */
559 static int use_module(struct module *a, struct module *b)
561 struct module_use *use;
564 if (b == NULL || already_uses(a, b)) return 1;
566 /* If we're interrupted or time out, we fail. */
567 if (wait_event_interruptible_timeout(
568 module_wq, (err = strong_try_module_get(b)) != -EBUSY,
570 printk("%s: gave up waiting for init of module %s.\n",
575 /* If strong_try_module_get() returned a different error, we fail. */
579 DEBUGP("Allocating new usage for %s.\n", a->name);
580 use = kmalloc(sizeof(*use), GFP_ATOMIC);
582 printk("%s: out of memory loading\n", a->name);
587 use->module_which_uses = a;
588 list_add(&use->list, &b->modules_which_use_me);
589 no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
593 /* Clear the unload stuff of the module. */
594 static void module_unload_free(struct module *mod)
598 list_for_each_entry(i, &modules, list) {
599 struct module_use *use;
601 list_for_each_entry(use, &i->modules_which_use_me, list) {
602 if (use->module_which_uses == mod) {
603 DEBUGP("%s unusing %s\n", mod->name, i->name);
605 list_del(&use->list);
607 sysfs_remove_link(i->holders_dir, mod->name);
608 /* There can be at most one match. */
615 #ifdef CONFIG_MODULE_FORCE_UNLOAD
616 static inline int try_force_unload(unsigned int flags)
618 int ret = (flags & O_TRUNC);
620 add_taint(TAINT_FORCED_RMMOD);
624 static inline int try_force_unload(unsigned int flags)
628 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
637 /* Whole machine is stopped with interrupts off when this runs. */
638 static int __try_stop_module(void *_sref)
640 struct stopref *sref = _sref;
642 /* If it's not unused, quit unless we're forcing. */
643 if (module_refcount(sref->mod) != 0) {
644 if (!(*sref->forced = try_force_unload(sref->flags)))
648 /* Mark it as dying. */
649 sref->mod->state = MODULE_STATE_GOING;
653 static int try_stop_module(struct module *mod, int flags, int *forced)
655 if (flags & O_NONBLOCK) {
656 struct stopref sref = { mod, flags, forced };
658 return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
660 /* We don't need to stop the machine for this. */
661 mod->state = MODULE_STATE_GOING;
667 unsigned int module_refcount(struct module *mod)
669 unsigned int i, total = 0;
671 for (i = 0; i < NR_CPUS; i++)
672 total += local_read(&mod->ref[i].count);
675 EXPORT_SYMBOL(module_refcount);
677 /* This exists whether we can unload or not */
678 static void free_module(struct module *mod);
680 static void wait_for_zero_refcount(struct module *mod)
682 /* Since we might sleep for some time, release the mutex first */
683 mutex_unlock(&module_mutex);
685 DEBUGP("Looking at refcount...\n");
686 set_current_state(TASK_UNINTERRUPTIBLE);
687 if (module_refcount(mod) == 0)
691 current->state = TASK_RUNNING;
692 mutex_lock(&module_mutex);
696 sys_delete_module(const char __user *name_user, unsigned int flags)
699 char name[MODULE_NAME_LEN];
702 if (!capable(CAP_SYS_MODULE))
705 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
707 name[MODULE_NAME_LEN-1] = '\0';
709 if (mutex_lock_interruptible(&module_mutex) != 0)
712 mod = find_module(name);
718 if (!list_empty(&mod->modules_which_use_me)) {
719 /* Other modules depend on us: get rid of them first. */
724 /* Doing init or already dying? */
725 if (mod->state != MODULE_STATE_LIVE) {
726 /* FIXME: if (force), slam module count and wake up
728 DEBUGP("%s already dying\n", mod->name);
733 /* If it has an init func, it must have an exit func to unload */
734 if (mod->init && !mod->exit) {
735 forced = try_force_unload(flags);
737 /* This module can't be removed */
743 /* Set this up before setting mod->state */
744 mod->waiter = current;
746 /* Stop the machine so refcounts can't move and disable module. */
747 ret = try_stop_module(mod, flags, &forced);
751 /* Never wait if forced. */
752 if (!forced && module_refcount(mod) != 0)
753 wait_for_zero_refcount(mod);
755 mutex_unlock(&module_mutex);
756 /* Final destruction now noone is using it. */
757 if (mod->exit != NULL)
759 blocking_notifier_call_chain(&module_notify_list,
760 MODULE_STATE_GOING, mod);
761 mutex_lock(&module_mutex);
762 /* Store the name of the last unloaded module for diagnostic purposes */
763 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
767 mutex_unlock(&module_mutex);
771 static void print_unload_info(struct seq_file *m, struct module *mod)
773 struct module_use *use;
774 int printed_something = 0;
776 seq_printf(m, " %u ", module_refcount(mod));
778 /* Always include a trailing , so userspace can differentiate
779 between this and the old multi-field proc format. */
780 list_for_each_entry(use, &mod->modules_which_use_me, list) {
781 printed_something = 1;
782 seq_printf(m, "%s,", use->module_which_uses->name);
785 if (mod->init != NULL && mod->exit == NULL) {
786 printed_something = 1;
787 seq_printf(m, "[permanent],");
790 if (!printed_something)
794 void __symbol_put(const char *symbol)
796 struct module *owner;
799 if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false)))
804 EXPORT_SYMBOL(__symbol_put);
806 void symbol_put_addr(void *addr)
808 struct module *modaddr;
810 if (core_kernel_text((unsigned long)addr))
813 if (!(modaddr = module_text_address((unsigned long)addr)))
817 EXPORT_SYMBOL_GPL(symbol_put_addr);
819 static ssize_t show_refcnt(struct module_attribute *mattr,
820 struct module *mod, char *buffer)
822 return sprintf(buffer, "%u\n", module_refcount(mod));
825 static struct module_attribute refcnt = {
826 .attr = { .name = "refcnt", .mode = 0444 },
830 void module_put(struct module *module)
833 unsigned int cpu = get_cpu();
834 local_dec(&module->ref[cpu].count);
835 /* Maybe they're waiting for us to drop reference? */
836 if (unlikely(!module_is_live(module)))
837 wake_up_process(module->waiter);
841 EXPORT_SYMBOL(module_put);
843 #else /* !CONFIG_MODULE_UNLOAD */
844 static void print_unload_info(struct seq_file *m, struct module *mod)
846 /* We don't know the usage count, or what modules are using. */
847 seq_printf(m, " - -");
850 static inline void module_unload_free(struct module *mod)
854 static inline int use_module(struct module *a, struct module *b)
856 return strong_try_module_get(b) == 0;
859 static inline void module_unload_init(struct module *mod)
862 #endif /* CONFIG_MODULE_UNLOAD */
864 static ssize_t show_initstate(struct module_attribute *mattr,
865 struct module *mod, char *buffer)
867 const char *state = "unknown";
869 switch (mod->state) {
870 case MODULE_STATE_LIVE:
873 case MODULE_STATE_COMING:
876 case MODULE_STATE_GOING:
880 return sprintf(buffer, "%s\n", state);
883 static struct module_attribute initstate = {
884 .attr = { .name = "initstate", .mode = 0444 },
885 .show = show_initstate,
888 static struct module_attribute *modinfo_attrs[] = {
892 #ifdef CONFIG_MODULE_UNLOAD
898 static const char vermagic[] = VERMAGIC_STRING;
900 static int try_to_force_load(struct module *mod, const char *symname)
902 #ifdef CONFIG_MODULE_FORCE_LOAD
903 if (!(tainted & TAINT_FORCED_MODULE))
904 printk("%s: no version for \"%s\" found: kernel tainted.\n",
906 add_taint_module(mod, TAINT_FORCED_MODULE);
913 #ifdef CONFIG_MODVERSIONS
914 static int check_version(Elf_Shdr *sechdrs,
915 unsigned int versindex,
918 const unsigned long *crc)
920 unsigned int i, num_versions;
921 struct modversion_info *versions;
923 /* Exporting module didn't supply crcs? OK, we're already tainted. */
927 /* No versions at all? modprobe --force does this. */
929 return try_to_force_load(mod, symname) == 0;
931 versions = (void *) sechdrs[versindex].sh_addr;
932 num_versions = sechdrs[versindex].sh_size
933 / sizeof(struct modversion_info);
935 for (i = 0; i < num_versions; i++) {
936 if (strcmp(versions[i].name, symname) != 0)
939 if (versions[i].crc == *crc)
941 DEBUGP("Found checksum %lX vs module %lX\n",
942 *crc, versions[i].crc);
946 printk(KERN_WARNING "%s: no symbol version for %s\n",
951 printk("%s: disagrees about version of symbol %s\n",
956 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
957 unsigned int versindex,
960 const unsigned long *crc;
962 if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false)))
964 return check_version(sechdrs, versindex, "struct_module", mod, crc);
967 /* First part is kernel version, which we ignore if module has crcs. */
968 static inline int same_magic(const char *amagic, const char *bmagic,
972 amagic += strcspn(amagic, " ");
973 bmagic += strcspn(bmagic, " ");
975 return strcmp(amagic, bmagic) == 0;
978 static inline int check_version(Elf_Shdr *sechdrs,
979 unsigned int versindex,
982 const unsigned long *crc)
987 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
988 unsigned int versindex,
994 static inline int same_magic(const char *amagic, const char *bmagic,
997 return strcmp(amagic, bmagic) == 0;
999 #endif /* CONFIG_MODVERSIONS */
1001 /* Resolve a symbol for this module. I.e. if we find one, record usage.
1002 Must be holding module_mutex. */
1003 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
1004 unsigned int versindex,
1008 struct module *owner;
1010 const unsigned long *crc;
1012 ret = find_symbol(name, &owner, &crc,
1013 !(mod->taints & TAINT_PROPRIETARY_MODULE), true);
1014 if (!IS_ERR_VALUE(ret)) {
1015 /* use_module can fail due to OOM,
1016 or module initialization or unloading */
1017 if (!check_version(sechdrs, versindex, name, mod, crc) ||
1018 !use_module(mod, owner))
1025 * /sys/module/foo/sections stuff
1026 * J. Corbet <corbet@lwn.net>
1028 #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1029 struct module_sect_attr
1031 struct module_attribute mattr;
1033 unsigned long address;
1036 struct module_sect_attrs
1038 struct attribute_group grp;
1039 unsigned int nsections;
1040 struct module_sect_attr attrs[0];
1043 static ssize_t module_sect_show(struct module_attribute *mattr,
1044 struct module *mod, char *buf)
1046 struct module_sect_attr *sattr =
1047 container_of(mattr, struct module_sect_attr, mattr);
1048 return sprintf(buf, "0x%lx\n", sattr->address);
1051 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1053 unsigned int section;
1055 for (section = 0; section < sect_attrs->nsections; section++)
1056 kfree(sect_attrs->attrs[section].name);
1060 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1061 char *secstrings, Elf_Shdr *sechdrs)
1063 unsigned int nloaded = 0, i, size[2];
1064 struct module_sect_attrs *sect_attrs;
1065 struct module_sect_attr *sattr;
1066 struct attribute **gattr;
1068 /* Count loaded sections and allocate structures */
1069 for (i = 0; i < nsect; i++)
1070 if (sechdrs[i].sh_flags & SHF_ALLOC)
1072 size[0] = ALIGN(sizeof(*sect_attrs)
1073 + nloaded * sizeof(sect_attrs->attrs[0]),
1074 sizeof(sect_attrs->grp.attrs[0]));
1075 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1076 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1077 if (sect_attrs == NULL)
1080 /* Setup section attributes. */
1081 sect_attrs->grp.name = "sections";
1082 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1084 sect_attrs->nsections = 0;
1085 sattr = §_attrs->attrs[0];
1086 gattr = §_attrs->grp.attrs[0];
1087 for (i = 0; i < nsect; i++) {
1088 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1090 sattr->address = sechdrs[i].sh_addr;
1091 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1093 if (sattr->name == NULL)
1095 sect_attrs->nsections++;
1096 sattr->mattr.show = module_sect_show;
1097 sattr->mattr.store = NULL;
1098 sattr->mattr.attr.name = sattr->name;
1099 sattr->mattr.attr.mode = S_IRUGO;
1100 *(gattr++) = &(sattr++)->mattr.attr;
1104 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1107 mod->sect_attrs = sect_attrs;
1110 free_sect_attrs(sect_attrs);
1113 static void remove_sect_attrs(struct module *mod)
1115 if (mod->sect_attrs) {
1116 sysfs_remove_group(&mod->mkobj.kobj,
1117 &mod->sect_attrs->grp);
1118 /* We are positive that no one is using any sect attrs
1119 * at this point. Deallocate immediately. */
1120 free_sect_attrs(mod->sect_attrs);
1121 mod->sect_attrs = NULL;
1126 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1129 struct module_notes_attrs {
1130 struct kobject *dir;
1132 struct bin_attribute attrs[0];
1135 static ssize_t module_notes_read(struct kobject *kobj,
1136 struct bin_attribute *bin_attr,
1137 char *buf, loff_t pos, size_t count)
1140 * The caller checked the pos and count against our size.
1142 memcpy(buf, bin_attr->private + pos, count);
1146 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1149 if (notes_attrs->dir) {
1151 sysfs_remove_bin_file(notes_attrs->dir,
1152 ¬es_attrs->attrs[i]);
1153 kobject_del(notes_attrs->dir);
1158 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1159 char *secstrings, Elf_Shdr *sechdrs)
1161 unsigned int notes, loaded, i;
1162 struct module_notes_attrs *notes_attrs;
1163 struct bin_attribute *nattr;
1165 /* Count notes sections and allocate structures. */
1167 for (i = 0; i < nsect; i++)
1168 if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
1169 (sechdrs[i].sh_type == SHT_NOTE))
1175 notes_attrs = kzalloc(sizeof(*notes_attrs)
1176 + notes * sizeof(notes_attrs->attrs[0]),
1178 if (notes_attrs == NULL)
1181 notes_attrs->notes = notes;
1182 nattr = ¬es_attrs->attrs[0];
1183 for (loaded = i = 0; i < nsect; ++i) {
1184 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1186 if (sechdrs[i].sh_type == SHT_NOTE) {
1187 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1188 nattr->attr.mode = S_IRUGO;
1189 nattr->size = sechdrs[i].sh_size;
1190 nattr->private = (void *) sechdrs[i].sh_addr;
1191 nattr->read = module_notes_read;
1197 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1198 if (!notes_attrs->dir)
1201 for (i = 0; i < notes; ++i)
1202 if (sysfs_create_bin_file(notes_attrs->dir,
1203 ¬es_attrs->attrs[i]))
1206 mod->notes_attrs = notes_attrs;
1210 free_notes_attrs(notes_attrs, i);
1213 static void remove_notes_attrs(struct module *mod)
1215 if (mod->notes_attrs)
1216 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1221 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1222 char *sectstrings, Elf_Shdr *sechdrs)
1226 static inline void remove_sect_attrs(struct module *mod)
1230 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1231 char *sectstrings, Elf_Shdr *sechdrs)
1235 static inline void remove_notes_attrs(struct module *mod)
1241 int module_add_modinfo_attrs(struct module *mod)
1243 struct module_attribute *attr;
1244 struct module_attribute *temp_attr;
1248 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1249 (ARRAY_SIZE(modinfo_attrs) + 1)),
1251 if (!mod->modinfo_attrs)
1254 temp_attr = mod->modinfo_attrs;
1255 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1257 (attr->test && attr->test(mod))) {
1258 memcpy(temp_attr, attr, sizeof(*temp_attr));
1259 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1266 void module_remove_modinfo_attrs(struct module *mod)
1268 struct module_attribute *attr;
1271 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1272 /* pick a field to test for end of list */
1273 if (!attr->attr.name)
1275 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1279 kfree(mod->modinfo_attrs);
1282 int mod_sysfs_init(struct module *mod)
1285 struct kobject *kobj;
1287 if (!module_sysfs_initialized) {
1288 printk(KERN_ERR "%s: module sysfs not initialized\n",
1294 kobj = kset_find_obj(module_kset, mod->name);
1296 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1302 mod->mkobj.mod = mod;
1304 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1305 mod->mkobj.kobj.kset = module_kset;
1306 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1309 kobject_put(&mod->mkobj.kobj);
1311 /* delay uevent until full sysfs population */
1316 int mod_sysfs_setup(struct module *mod,
1317 struct kernel_param *kparam,
1318 unsigned int num_params)
1322 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1323 if (!mod->holders_dir) {
1328 err = module_param_sysfs_setup(mod, kparam, num_params);
1330 goto out_unreg_holders;
1332 err = module_add_modinfo_attrs(mod);
1334 goto out_unreg_param;
1336 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1340 module_param_sysfs_remove(mod);
1342 kobject_put(mod->holders_dir);
1344 kobject_put(&mod->mkobj.kobj);
1348 static void mod_sysfs_fini(struct module *mod)
1350 kobject_put(&mod->mkobj.kobj);
1353 #else /* CONFIG_SYSFS */
1355 static void mod_sysfs_fini(struct module *mod)
1359 #endif /* CONFIG_SYSFS */
1361 static void mod_kobject_remove(struct module *mod)
1363 module_remove_modinfo_attrs(mod);
1364 module_param_sysfs_remove(mod);
1365 kobject_put(mod->mkobj.drivers_dir);
1366 kobject_put(mod->holders_dir);
1367 mod_sysfs_fini(mod);
1371 * link the module with the whole machine is stopped with interrupts off
1372 * - this defends against kallsyms not taking locks
1374 static int __link_module(void *_mod)
1376 struct module *mod = _mod;
1377 list_add(&mod->list, &modules);
1382 * unlink the module with the whole machine is stopped with interrupts off
1383 * - this defends against kallsyms not taking locks
1385 static int __unlink_module(void *_mod)
1387 struct module *mod = _mod;
1388 list_del(&mod->list);
1392 /* Free a module, remove from lists, etc (must hold module_mutex). */
1393 static void free_module(struct module *mod)
1395 /* Delete from various lists */
1396 stop_machine_run(__unlink_module, mod, NR_CPUS);
1397 remove_notes_attrs(mod);
1398 remove_sect_attrs(mod);
1399 mod_kobject_remove(mod);
1401 unwind_remove_table(mod->unwind_info, 0);
1403 /* Arch-specific cleanup. */
1404 module_arch_cleanup(mod);
1406 /* Module unload stuff */
1407 module_unload_free(mod);
1409 /* This may be NULL, but that's OK */
1410 module_free(mod, mod->module_init);
1413 percpu_modfree(mod->percpu);
1415 /* Free lock-classes: */
1416 lockdep_free_key_range(mod->module_core, mod->core_size);
1418 /* Finally, free the core (containing the module structure) */
1419 module_free(mod, mod->module_core);
1422 void *__symbol_get(const char *symbol)
1424 struct module *owner;
1425 unsigned long value;
1428 value = find_symbol(symbol, &owner, NULL, true, true);
1429 if (IS_ERR_VALUE(value))
1431 else if (strong_try_module_get(owner))
1435 return (void *)value;
1437 EXPORT_SYMBOL_GPL(__symbol_get);
1440 * Ensure that an exported symbol [global namespace] does not already exist
1441 * in the kernel or in some other module's exported symbol table.
1443 static int verify_export_symbols(struct module *mod)
1446 struct module *owner;
1447 const struct kernel_symbol *s;
1449 const struct kernel_symbol *sym;
1452 { mod->syms, mod->num_syms },
1453 { mod->gpl_syms, mod->num_gpl_syms },
1454 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1455 { mod->unused_syms, mod->num_unused_syms },
1456 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1459 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1460 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1461 if (!IS_ERR_VALUE(find_symbol(s->name, &owner,
1462 NULL, true, false))) {
1464 "%s: exports duplicate symbol %s"
1466 mod->name, s->name, module_name(owner));
1474 /* Change all symbols so that st_value encodes the pointer directly. */
1475 static int simplify_symbols(Elf_Shdr *sechdrs,
1476 unsigned int symindex,
1478 unsigned int versindex,
1479 unsigned int pcpuindex,
1482 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1483 unsigned long secbase;
1484 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1487 for (i = 1; i < n; i++) {
1488 switch (sym[i].st_shndx) {
1490 /* We compiled with -fno-common. These are not
1491 supposed to happen. */
1492 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1493 printk("%s: please compile with -fno-common\n",
1499 /* Don't need to do anything */
1500 DEBUGP("Absolute symbol: 0x%08lx\n",
1501 (long)sym[i].st_value);
1506 = resolve_symbol(sechdrs, versindex,
1507 strtab + sym[i].st_name, mod);
1509 /* Ok if resolved. */
1510 if (!IS_ERR_VALUE(sym[i].st_value))
1513 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1516 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1517 mod->name, strtab + sym[i].st_name);
1522 /* Divert to percpu allocation if a percpu var. */
1523 if (sym[i].st_shndx == pcpuindex)
1524 secbase = (unsigned long)mod->percpu;
1526 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1527 sym[i].st_value += secbase;
1535 /* Update size with this section: return offset. */
1536 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
1540 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1541 *size = ret + sechdr->sh_size;
1545 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1546 might -- code, read-only data, read-write data, small data. Tally
1547 sizes, and place the offsets into sh_entsize fields: high bit means it
1549 static void layout_sections(struct module *mod,
1550 const Elf_Ehdr *hdr,
1552 const char *secstrings)
1554 static unsigned long const masks[][2] = {
1555 /* NOTE: all executable code must be the first section
1556 * in this array; otherwise modify the text_size
1557 * finder in the two loops below */
1558 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1559 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1560 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1561 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1565 for (i = 0; i < hdr->e_shnum; i++)
1566 sechdrs[i].sh_entsize = ~0UL;
1568 DEBUGP("Core section allocation order:\n");
1569 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1570 for (i = 0; i < hdr->e_shnum; ++i) {
1571 Elf_Shdr *s = &sechdrs[i];
1573 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1574 || (s->sh_flags & masks[m][1])
1575 || s->sh_entsize != ~0UL
1576 || strncmp(secstrings + s->sh_name,
1579 s->sh_entsize = get_offset(&mod->core_size, s);
1580 DEBUGP("\t%s\n", secstrings + s->sh_name);
1583 mod->core_text_size = mod->core_size;
1586 DEBUGP("Init section allocation order:\n");
1587 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1588 for (i = 0; i < hdr->e_shnum; ++i) {
1589 Elf_Shdr *s = &sechdrs[i];
1591 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1592 || (s->sh_flags & masks[m][1])
1593 || s->sh_entsize != ~0UL
1594 || strncmp(secstrings + s->sh_name,
1597 s->sh_entsize = (get_offset(&mod->init_size, s)
1598 | INIT_OFFSET_MASK);
1599 DEBUGP("\t%s\n", secstrings + s->sh_name);
1602 mod->init_text_size = mod->init_size;
1606 static void set_license(struct module *mod, const char *license)
1609 license = "unspecified";
1611 if (!license_is_gpl_compatible(license)) {
1612 if (!(tainted & TAINT_PROPRIETARY_MODULE))
1613 printk(KERN_WARNING "%s: module license '%s' taints "
1614 "kernel.\n", mod->name, license);
1615 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1619 /* Parse tag=value strings from .modinfo section */
1620 static char *next_string(char *string, unsigned long *secsize)
1622 /* Skip non-zero chars */
1625 if ((*secsize)-- <= 1)
1629 /* Skip any zero padding. */
1630 while (!string[0]) {
1632 if ((*secsize)-- <= 1)
1638 static char *get_modinfo(Elf_Shdr *sechdrs,
1643 unsigned int taglen = strlen(tag);
1644 unsigned long size = sechdrs[info].sh_size;
1646 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1647 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1648 return p + taglen + 1;
1653 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1654 unsigned int infoindex)
1656 struct module_attribute *attr;
1659 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1662 get_modinfo(sechdrs,
1668 #ifdef CONFIG_KALLSYMS
1669 static int is_exported(const char *name, const struct module *mod)
1671 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1674 if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1681 static char elf_type(const Elf_Sym *sym,
1683 const char *secstrings,
1686 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1687 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1692 if (sym->st_shndx == SHN_UNDEF)
1694 if (sym->st_shndx == SHN_ABS)
1696 if (sym->st_shndx >= SHN_LORESERVE)
1698 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1700 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1701 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1702 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1704 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1709 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1710 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1715 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1716 ".debug", strlen(".debug")) == 0)
1721 static void add_kallsyms(struct module *mod,
1723 unsigned int symindex,
1724 unsigned int strindex,
1725 const char *secstrings)
1729 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1730 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1731 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1733 /* Set types up while we still have access to sections. */
1734 for (i = 0; i < mod->num_symtab; i++)
1735 mod->symtab[i].st_info
1736 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1739 static inline void add_kallsyms(struct module *mod,
1741 unsigned int symindex,
1742 unsigned int strindex,
1743 const char *secstrings)
1746 #endif /* CONFIG_KALLSYMS */
1748 /* Allocate and load the module: note that size of section 0 is always
1749 zero, and we rely on this for optional sections. */
1750 static struct module *load_module(void __user *umod,
1752 const char __user *uargs)
1756 char *secstrings, *args, *modmagic, *strtab = NULL;
1758 unsigned int symindex = 0;
1759 unsigned int strindex = 0;
1760 unsigned int setupindex;
1761 unsigned int exindex;
1762 unsigned int exportindex;
1763 unsigned int modindex;
1764 unsigned int obsparmindex;
1765 unsigned int infoindex;
1766 unsigned int gplindex;
1767 unsigned int crcindex;
1768 unsigned int gplcrcindex;
1769 unsigned int versindex;
1770 unsigned int pcpuindex;
1771 unsigned int gplfutureindex;
1772 unsigned int gplfuturecrcindex;
1773 unsigned int unwindex = 0;
1774 unsigned int unusedindex;
1775 unsigned int unusedcrcindex;
1776 unsigned int unusedgplindex;
1777 unsigned int unusedgplcrcindex;
1778 unsigned int markersindex;
1779 unsigned int markersstringsindex;
1782 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1783 struct exception_table_entry *extable;
1784 mm_segment_t old_fs;
1786 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1788 if (len < sizeof(*hdr))
1789 return ERR_PTR(-ENOEXEC);
1791 /* Suck in entire file: we'll want most of it. */
1792 /* vmalloc barfs on "unusual" numbers. Check here */
1793 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1794 return ERR_PTR(-ENOMEM);
1795 if (copy_from_user(hdr, umod, len) != 0) {
1800 /* Sanity checks against insmoding binaries or wrong arch,
1801 weird elf version */
1802 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
1803 || hdr->e_type != ET_REL
1804 || !elf_check_arch(hdr)
1805 || hdr->e_shentsize != sizeof(*sechdrs)) {
1810 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1813 /* Convenience variables */
1814 sechdrs = (void *)hdr + hdr->e_shoff;
1815 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1816 sechdrs[0].sh_addr = 0;
1818 for (i = 1; i < hdr->e_shnum; i++) {
1819 if (sechdrs[i].sh_type != SHT_NOBITS
1820 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1823 /* Mark all sections sh_addr with their address in the
1825 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1827 /* Internal symbols and strings. */
1828 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1830 strindex = sechdrs[i].sh_link;
1831 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1833 #ifndef CONFIG_MODULE_UNLOAD
1834 /* Don't load .exit sections */
1835 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1836 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1840 modindex = find_sec(hdr, sechdrs, secstrings,
1841 ".gnu.linkonce.this_module");
1843 printk(KERN_WARNING "No module found in object\n");
1847 mod = (void *)sechdrs[modindex].sh_addr;
1849 if (symindex == 0) {
1850 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1856 /* Optional sections */
1857 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1858 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1859 gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1860 unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
1861 unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
1862 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1863 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1864 gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1865 unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
1866 unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
1867 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1868 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1869 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1870 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1871 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1872 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1873 #ifdef ARCH_UNWIND_SECTION_NAME
1874 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1877 /* Don't keep modinfo and version sections. */
1878 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1879 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1880 #ifdef CONFIG_KALLSYMS
1881 /* Keep symbol and string tables for decoding later. */
1882 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1883 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1886 sechdrs[unwindex].sh_flags |= SHF_ALLOC;
1888 /* Check module struct version now, before we try to use module. */
1889 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1894 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1895 /* This is allowed: modprobe --force will invalidate it. */
1897 err = try_to_force_load(mod, "magic");
1900 } else if (!same_magic(modmagic, vermagic, versindex)) {
1901 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1902 mod->name, modmagic, vermagic);
1907 /* Now copy in args */
1908 args = strndup_user(uargs, ~0UL >> 1);
1910 err = PTR_ERR(args);
1914 if (find_module(mod->name)) {
1919 mod->state = MODULE_STATE_COMING;
1921 /* Allow arches to frob section contents and sizes. */
1922 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1927 /* We have a special allocation for this section. */
1928 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1929 sechdrs[pcpuindex].sh_addralign,
1935 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1936 mod->percpu = percpu;
1939 /* Determine total sizes, and put offsets in sh_entsize. For now
1940 this is done generically; there doesn't appear to be any
1941 special cases for the architectures. */
1942 layout_sections(mod, hdr, sechdrs, secstrings);
1944 /* Do the allocs. */
1945 ptr = module_alloc(mod->core_size);
1950 memset(ptr, 0, mod->core_size);
1951 mod->module_core = ptr;
1953 ptr = module_alloc(mod->init_size);
1954 if (!ptr && mod->init_size) {
1958 memset(ptr, 0, mod->init_size);
1959 mod->module_init = ptr;
1961 /* Transfer each section which specifies SHF_ALLOC */
1962 DEBUGP("final section addresses:\n");
1963 for (i = 0; i < hdr->e_shnum; i++) {
1966 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1969 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
1970 dest = mod->module_init
1971 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
1973 dest = mod->module_core + sechdrs[i].sh_entsize;
1975 if (sechdrs[i].sh_type != SHT_NOBITS)
1976 memcpy(dest, (void *)sechdrs[i].sh_addr,
1977 sechdrs[i].sh_size);
1978 /* Update sh_addr to point to copy in image. */
1979 sechdrs[i].sh_addr = (unsigned long)dest;
1980 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
1982 /* Module has been moved. */
1983 mod = (void *)sechdrs[modindex].sh_addr;
1985 /* Now we've moved module, initialize linked lists, etc. */
1986 module_unload_init(mod);
1988 /* add kobject, so we can reference it. */
1989 err = mod_sysfs_init(mod);
1993 /* Set up license info based on the info section */
1994 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
1997 * ndiswrapper is under GPL by itself, but loads proprietary modules.
1998 * Don't use add_taint_module(), as it would prevent ndiswrapper from
1999 * using GPL-only symbols it needs.
2001 if (strcmp(mod->name, "ndiswrapper") == 0)
2002 add_taint(TAINT_PROPRIETARY_MODULE);
2004 /* driverloader was caught wrongly pretending to be under GPL */
2005 if (strcmp(mod->name, "driverloader") == 0)
2006 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2008 /* Set up MODINFO_ATTR fields */
2009 setup_modinfo(mod, sechdrs, infoindex);
2011 /* Fix up syms, so that st_value is a pointer to location. */
2012 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2017 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
2018 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
2019 mod->syms = (void *)sechdrs[exportindex].sh_addr;
2021 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
2022 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
2023 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
2025 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
2026 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
2027 sizeof(*mod->gpl_future_syms);
2028 mod->num_unused_syms = sechdrs[unusedindex].sh_size /
2029 sizeof(*mod->unused_syms);
2030 mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
2031 sizeof(*mod->unused_gpl_syms);
2032 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
2033 if (gplfuturecrcindex)
2034 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
2036 mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
2038 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
2039 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
2040 if (unusedgplcrcindex)
2041 mod->unused_gpl_crcs
2042 = (void *)sechdrs[unusedgplcrcindex].sh_addr;
2044 #ifdef CONFIG_MODVERSIONS
2045 if ((mod->num_syms && !crcindex) ||
2046 (mod->num_gpl_syms && !gplcrcindex) ||
2047 (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
2048 (mod->num_unused_syms && !unusedcrcindex) ||
2049 (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
2050 printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name);
2051 err = try_to_force_load(mod, "nocrc");
2056 markersindex = find_sec(hdr, sechdrs, secstrings, "__markers");
2057 markersstringsindex = find_sec(hdr, sechdrs, secstrings,
2058 "__markers_strings");
2060 /* Now do relocations. */
2061 for (i = 1; i < hdr->e_shnum; i++) {
2062 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2063 unsigned int info = sechdrs[i].sh_info;
2065 /* Not a valid relocation section? */
2066 if (info >= hdr->e_shnum)
2069 /* Don't bother with non-allocated sections */
2070 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2073 if (sechdrs[i].sh_type == SHT_REL)
2074 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2075 else if (sechdrs[i].sh_type == SHT_RELA)
2076 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2081 #ifdef CONFIG_MARKERS
2082 mod->markers = (void *)sechdrs[markersindex].sh_addr;
2084 sechdrs[markersindex].sh_size / sizeof(*mod->markers);
2087 /* Find duplicate symbols */
2088 err = verify_export_symbols(mod);
2093 /* Set up and sort exception table */
2094 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
2095 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
2096 sort_extable(extable, extable + mod->num_exentries);
2098 /* Finally, copy percpu area over. */
2099 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
2100 sechdrs[pcpuindex].sh_size);
2102 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
2104 #ifdef CONFIG_MARKERS
2106 marker_update_probe_range(mod->markers,
2107 mod->markers + mod->num_markers);
2109 err = module_finalize(hdr, sechdrs, mod);
2113 /* flush the icache in correct context */
2118 * Flush the instruction cache, since we've played with text.
2119 * Do it before processing of module parameters, so the module
2120 * can provide parameter accessor functions of its own.
2122 if (mod->module_init)
2123 flush_icache_range((unsigned long)mod->module_init,
2124 (unsigned long)mod->module_init
2126 flush_icache_range((unsigned long)mod->module_core,
2127 (unsigned long)mod->module_core + mod->core_size);
2133 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2136 /* Now sew it into the lists so we can get lockdep and oops
2137 * info during argument parsing. Noone should access us, since
2138 * strong_try_module_get() will fail. */
2139 stop_machine_run(__link_module, mod, NR_CPUS);
2141 /* Size of section 0 is 0, so this works well if no params */
2142 err = parse_args(mod->name, mod->args,
2143 (struct kernel_param *)
2144 sechdrs[setupindex].sh_addr,
2145 sechdrs[setupindex].sh_size
2146 / sizeof(struct kernel_param),
2151 err = mod_sysfs_setup(mod,
2152 (struct kernel_param *)
2153 sechdrs[setupindex].sh_addr,
2154 sechdrs[setupindex].sh_size
2155 / sizeof(struct kernel_param));
2158 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2159 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2161 /* Size of section 0 is 0, so this works well if no unwind info. */
2162 mod->unwind_info = unwind_add_table(mod,
2163 (void *)sechdrs[unwindex].sh_addr,
2164 sechdrs[unwindex].sh_size);
2166 /* Get rid of temporary copy */
2173 stop_machine_run(__unlink_module, mod, NR_CPUS);
2174 module_arch_cleanup(mod);
2176 kobject_del(&mod->mkobj.kobj);
2177 kobject_put(&mod->mkobj.kobj);
2179 module_unload_free(mod);
2180 module_free(mod, mod->module_init);
2182 module_free(mod, mod->module_core);
2185 percpu_modfree(percpu);
2190 return ERR_PTR(err);
2193 printk(KERN_ERR "Module len %lu truncated\n", len);
2198 /* This is where the real work happens */
2200 sys_init_module(void __user *umod,
2202 const char __user *uargs)
2207 /* Must have permission */
2208 if (!capable(CAP_SYS_MODULE))
2211 /* Only one module load at a time, please */
2212 if (mutex_lock_interruptible(&module_mutex) != 0)
2215 /* Do all the hard work */
2216 mod = load_module(umod, len, uargs);
2218 mutex_unlock(&module_mutex);
2219 return PTR_ERR(mod);
2222 /* Drop lock so they can recurse */
2223 mutex_unlock(&module_mutex);
2225 blocking_notifier_call_chain(&module_notify_list,
2226 MODULE_STATE_COMING, mod);
2228 /* Start the module */
2229 if (mod->init != NULL)
2232 /* Init routine failed: abort. Try to protect us from
2233 buggy refcounters. */
2234 mod->state = MODULE_STATE_GOING;
2235 synchronize_sched();
2237 blocking_notifier_call_chain(&module_notify_list,
2238 MODULE_STATE_GOING, mod);
2239 mutex_lock(&module_mutex);
2241 mutex_unlock(&module_mutex);
2242 wake_up(&module_wq);
2246 printk(KERN_WARNING "%s: '%s'->init suspiciously returned %d, "
2247 "it should follow 0/-E convention\n"
2248 KERN_WARNING "%s: loading module anyway...\n",
2249 __func__, mod->name, ret,
2254 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2255 mod->state = MODULE_STATE_LIVE;
2256 wake_up(&module_wq);
2258 mutex_lock(&module_mutex);
2259 /* Drop initial reference. */
2261 unwind_remove_table(mod->unwind_info, 1);
2262 module_free(mod, mod->module_init);
2263 mod->module_init = NULL;
2265 mod->init_text_size = 0;
2266 mutex_unlock(&module_mutex);
2271 static inline int within(unsigned long addr, void *start, unsigned long size)
2273 return ((void *)addr >= start && (void *)addr < start + size);
2276 #ifdef CONFIG_KALLSYMS
2278 * This ignores the intensely annoying "mapping symbols" found
2279 * in ARM ELF files: $a, $t and $d.
2281 static inline int is_arm_mapping_symbol(const char *str)
2283 return str[0] == '$' && strchr("atd", str[1])
2284 && (str[2] == '\0' || str[2] == '.');
2287 static const char *get_ksymbol(struct module *mod,
2289 unsigned long *size,
2290 unsigned long *offset)
2292 unsigned int i, best = 0;
2293 unsigned long nextval;
2295 /* At worse, next value is at end of module */
2296 if (within(addr, mod->module_init, mod->init_size))
2297 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2299 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2301 /* Scan for closest preceeding symbol, and next symbol. (ELF
2302 starts real symbols at 1). */
2303 for (i = 1; i < mod->num_symtab; i++) {
2304 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2307 /* We ignore unnamed symbols: they're uninformative
2308 * and inserted at a whim. */
2309 if (mod->symtab[i].st_value <= addr
2310 && mod->symtab[i].st_value > mod->symtab[best].st_value
2311 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2312 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2314 if (mod->symtab[i].st_value > addr
2315 && mod->symtab[i].st_value < nextval
2316 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2317 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2318 nextval = mod->symtab[i].st_value;
2325 *size = nextval - mod->symtab[best].st_value;
2327 *offset = addr - mod->symtab[best].st_value;
2328 return mod->strtab + mod->symtab[best].st_name;
2331 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2332 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2333 const char *module_address_lookup(unsigned long addr,
2334 unsigned long *size,
2335 unsigned long *offset,
2340 const char *ret = NULL;
2343 list_for_each_entry(mod, &modules, list) {
2344 if (within(addr, mod->module_init, mod->init_size)
2345 || within(addr, mod->module_core, mod->core_size)) {
2347 *modname = mod->name;
2348 ret = get_ksymbol(mod, addr, size, offset);
2352 /* Make a copy in here where it's safe */
2354 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2361 int lookup_module_symbol_name(unsigned long addr, char *symname)
2366 list_for_each_entry(mod, &modules, list) {
2367 if (within(addr, mod->module_init, mod->init_size) ||
2368 within(addr, mod->module_core, mod->core_size)) {
2371 sym = get_ksymbol(mod, addr, NULL, NULL);
2374 strlcpy(symname, sym, KSYM_NAME_LEN);
2384 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2385 unsigned long *offset, char *modname, char *name)
2390 list_for_each_entry(mod, &modules, list) {
2391 if (within(addr, mod->module_init, mod->init_size) ||
2392 within(addr, mod->module_core, mod->core_size)) {
2395 sym = get_ksymbol(mod, addr, size, offset);
2399 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2401 strlcpy(name, sym, KSYM_NAME_LEN);
2411 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2412 char *name, char *module_name, int *exported)
2417 list_for_each_entry(mod, &modules, list) {
2418 if (symnum < mod->num_symtab) {
2419 *value = mod->symtab[symnum].st_value;
2420 *type = mod->symtab[symnum].st_info;
2421 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2423 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2424 *exported = is_exported(name, mod);
2428 symnum -= mod->num_symtab;
2434 static unsigned long mod_find_symname(struct module *mod, const char *name)
2438 for (i = 0; i < mod->num_symtab; i++)
2439 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2440 mod->symtab[i].st_info != 'U')
2441 return mod->symtab[i].st_value;
2445 /* Look for this name: can be of form module:name. */
2446 unsigned long module_kallsyms_lookup_name(const char *name)
2450 unsigned long ret = 0;
2452 /* Don't lock: we're in enough trouble already. */
2454 if ((colon = strchr(name, ':')) != NULL) {
2456 if ((mod = find_module(name)) != NULL)
2457 ret = mod_find_symname(mod, colon+1);
2460 list_for_each_entry(mod, &modules, list)
2461 if ((ret = mod_find_symname(mod, name)) != 0)
2467 #endif /* CONFIG_KALLSYMS */
2469 /* Called by the /proc file system to return a list of modules. */
2470 static void *m_start(struct seq_file *m, loff_t *pos)
2472 mutex_lock(&module_mutex);
2473 return seq_list_start(&modules, *pos);
2476 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2478 return seq_list_next(p, &modules, pos);
2481 static void m_stop(struct seq_file *m, void *p)
2483 mutex_unlock(&module_mutex);
2486 static char *module_flags(struct module *mod, char *buf)
2491 mod->state == MODULE_STATE_GOING ||
2492 mod->state == MODULE_STATE_COMING) {
2494 if (mod->taints & TAINT_PROPRIETARY_MODULE)
2496 if (mod->taints & TAINT_FORCED_MODULE)
2499 * TAINT_FORCED_RMMOD: could be added.
2500 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2504 /* Show a - for module-is-being-unloaded */
2505 if (mod->state == MODULE_STATE_GOING)
2507 /* Show a + for module-is-being-loaded */
2508 if (mod->state == MODULE_STATE_COMING)
2517 static int m_show(struct seq_file *m, void *p)
2519 struct module *mod = list_entry(p, struct module, list);
2522 seq_printf(m, "%s %lu",
2523 mod->name, mod->init_size + mod->core_size);
2524 print_unload_info(m, mod);
2526 /* Informative for users. */
2527 seq_printf(m, " %s",
2528 mod->state == MODULE_STATE_GOING ? "Unloading":
2529 mod->state == MODULE_STATE_COMING ? "Loading":
2531 /* Used by oprofile and other similar tools. */
2532 seq_printf(m, " 0x%p", mod->module_core);
2536 seq_printf(m, " %s", module_flags(mod, buf));
2538 seq_printf(m, "\n");
2542 /* Format: modulename size refcount deps address
2544 Where refcount is a number or -, and deps is a comma-separated list
2547 const struct seq_operations modules_op = {
2554 /* Given an address, look for it in the module exception tables. */
2555 const struct exception_table_entry *search_module_extables(unsigned long addr)
2557 const struct exception_table_entry *e = NULL;
2561 list_for_each_entry(mod, &modules, list) {
2562 if (mod->num_exentries == 0)
2565 e = search_extable(mod->extable,
2566 mod->extable + mod->num_exentries - 1,
2573 /* Now, if we found one, we are running inside it now, hence
2574 we cannot unload the module, hence no refcnt needed. */
2579 * Is this a valid module address?
2581 int is_module_address(unsigned long addr)
2587 list_for_each_entry(mod, &modules, list) {
2588 if (within(addr, mod->module_core, mod->core_size)) {
2600 /* Is this a valid kernel address? */
2601 struct module *__module_text_address(unsigned long addr)
2605 list_for_each_entry(mod, &modules, list)
2606 if (within(addr, mod->module_init, mod->init_text_size)
2607 || within(addr, mod->module_core, mod->core_text_size))
2612 struct module *module_text_address(unsigned long addr)
2617 mod = __module_text_address(addr);
2623 /* Don't grab lock, we're oopsing. */
2624 void print_modules(void)
2629 printk("Modules linked in:");
2630 list_for_each_entry(mod, &modules, list)
2631 printk(" %s%s", mod->name, module_flags(mod, buf));
2632 if (last_unloaded_module[0])
2633 printk(" [last unloaded: %s]", last_unloaded_module);
2637 #ifdef CONFIG_MODVERSIONS
2638 /* Generate the signature for struct module here, too, for modversions. */
2639 void struct_module(struct module *mod) { return; }
2640 EXPORT_SYMBOL(struct_module);
2643 #ifdef CONFIG_MARKERS
2644 void module_update_markers(void)
2648 mutex_lock(&module_mutex);
2649 list_for_each_entry(mod, &modules, list)
2651 marker_update_probe_range(mod->markers,
2652 mod->markers + mod->num_markers);
2653 mutex_unlock(&module_mutex);