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 are told to block. */
643 if ((sref->flags & O_NONBLOCK) && 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 struct stopref sref = { mod, flags, forced };
657 return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
660 unsigned int module_refcount(struct module *mod)
662 unsigned int i, total = 0;
664 for (i = 0; i < NR_CPUS; i++)
665 total += local_read(&mod->ref[i].count);
668 EXPORT_SYMBOL(module_refcount);
670 /* This exists whether we can unload or not */
671 static void free_module(struct module *mod);
673 static void wait_for_zero_refcount(struct module *mod)
675 /* Since we might sleep for some time, release the mutex first */
676 mutex_unlock(&module_mutex);
678 DEBUGP("Looking at refcount...\n");
679 set_current_state(TASK_UNINTERRUPTIBLE);
680 if (module_refcount(mod) == 0)
684 current->state = TASK_RUNNING;
685 mutex_lock(&module_mutex);
689 sys_delete_module(const char __user *name_user, unsigned int flags)
692 char name[MODULE_NAME_LEN];
695 if (!capable(CAP_SYS_MODULE))
698 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
700 name[MODULE_NAME_LEN-1] = '\0';
702 if (mutex_lock_interruptible(&module_mutex) != 0)
705 mod = find_module(name);
711 if (!list_empty(&mod->modules_which_use_me)) {
712 /* Other modules depend on us: get rid of them first. */
717 /* Doing init or already dying? */
718 if (mod->state != MODULE_STATE_LIVE) {
719 /* FIXME: if (force), slam module count and wake up
721 DEBUGP("%s already dying\n", mod->name);
726 /* If it has an init func, it must have an exit func to unload */
727 if (mod->init && !mod->exit) {
728 forced = try_force_unload(flags);
730 /* This module can't be removed */
736 /* Set this up before setting mod->state */
737 mod->waiter = current;
739 /* Stop the machine so refcounts can't move and disable module. */
740 ret = try_stop_module(mod, flags, &forced);
744 /* Never wait if forced. */
745 if (!forced && module_refcount(mod) != 0)
746 wait_for_zero_refcount(mod);
748 mutex_unlock(&module_mutex);
749 /* Final destruction now noone is using it. */
750 if (mod->exit != NULL)
752 blocking_notifier_call_chain(&module_notify_list,
753 MODULE_STATE_GOING, mod);
754 mutex_lock(&module_mutex);
755 /* Store the name of the last unloaded module for diagnostic purposes */
756 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
760 mutex_unlock(&module_mutex);
764 static void print_unload_info(struct seq_file *m, struct module *mod)
766 struct module_use *use;
767 int printed_something = 0;
769 seq_printf(m, " %u ", module_refcount(mod));
771 /* Always include a trailing , so userspace can differentiate
772 between this and the old multi-field proc format. */
773 list_for_each_entry(use, &mod->modules_which_use_me, list) {
774 printed_something = 1;
775 seq_printf(m, "%s,", use->module_which_uses->name);
778 if (mod->init != NULL && mod->exit == NULL) {
779 printed_something = 1;
780 seq_printf(m, "[permanent],");
783 if (!printed_something)
787 void __symbol_put(const char *symbol)
789 struct module *owner;
792 if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false)))
797 EXPORT_SYMBOL(__symbol_put);
799 void symbol_put_addr(void *addr)
801 struct module *modaddr;
803 if (core_kernel_text((unsigned long)addr))
806 if (!(modaddr = module_text_address((unsigned long)addr)))
810 EXPORT_SYMBOL_GPL(symbol_put_addr);
812 static ssize_t show_refcnt(struct module_attribute *mattr,
813 struct module *mod, char *buffer)
815 return sprintf(buffer, "%u\n", module_refcount(mod));
818 static struct module_attribute refcnt = {
819 .attr = { .name = "refcnt", .mode = 0444 },
823 void module_put(struct module *module)
826 unsigned int cpu = get_cpu();
827 local_dec(&module->ref[cpu].count);
828 /* Maybe they're waiting for us to drop reference? */
829 if (unlikely(!module_is_live(module)))
830 wake_up_process(module->waiter);
834 EXPORT_SYMBOL(module_put);
836 #else /* !CONFIG_MODULE_UNLOAD */
837 static void print_unload_info(struct seq_file *m, struct module *mod)
839 /* We don't know the usage count, or what modules are using. */
840 seq_printf(m, " - -");
843 static inline void module_unload_free(struct module *mod)
847 static inline int use_module(struct module *a, struct module *b)
849 return strong_try_module_get(b) == 0;
852 static inline void module_unload_init(struct module *mod)
855 #endif /* CONFIG_MODULE_UNLOAD */
857 static ssize_t show_initstate(struct module_attribute *mattr,
858 struct module *mod, char *buffer)
860 const char *state = "unknown";
862 switch (mod->state) {
863 case MODULE_STATE_LIVE:
866 case MODULE_STATE_COMING:
869 case MODULE_STATE_GOING:
873 return sprintf(buffer, "%s\n", state);
876 static struct module_attribute initstate = {
877 .attr = { .name = "initstate", .mode = 0444 },
878 .show = show_initstate,
881 static struct module_attribute *modinfo_attrs[] = {
885 #ifdef CONFIG_MODULE_UNLOAD
891 static const char vermagic[] = VERMAGIC_STRING;
893 static int try_to_force_load(struct module *mod, const char *symname)
895 #ifdef CONFIG_MODULE_FORCE_LOAD
896 if (!(tainted & TAINT_FORCED_MODULE))
897 printk("%s: no version for \"%s\" found: kernel tainted.\n",
899 add_taint_module(mod, TAINT_FORCED_MODULE);
906 #ifdef CONFIG_MODVERSIONS
907 static int check_version(Elf_Shdr *sechdrs,
908 unsigned int versindex,
911 const unsigned long *crc)
913 unsigned int i, num_versions;
914 struct modversion_info *versions;
916 /* Exporting module didn't supply crcs? OK, we're already tainted. */
920 /* No versions at all? modprobe --force does this. */
922 return try_to_force_load(mod, symname) == 0;
924 versions = (void *) sechdrs[versindex].sh_addr;
925 num_versions = sechdrs[versindex].sh_size
926 / sizeof(struct modversion_info);
928 for (i = 0; i < num_versions; i++) {
929 if (strcmp(versions[i].name, symname) != 0)
932 if (versions[i].crc == *crc)
934 DEBUGP("Found checksum %lX vs module %lX\n",
935 *crc, versions[i].crc);
939 printk(KERN_WARNING "%s: no symbol version for %s\n",
944 printk("%s: disagrees about version of symbol %s\n",
949 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
950 unsigned int versindex,
953 const unsigned long *crc;
955 if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false)))
957 return check_version(sechdrs, versindex, "struct_module", mod, crc);
960 /* First part is kernel version, which we ignore if module has crcs. */
961 static inline int same_magic(const char *amagic, const char *bmagic,
965 amagic += strcspn(amagic, " ");
966 bmagic += strcspn(bmagic, " ");
968 return strcmp(amagic, bmagic) == 0;
971 static inline int check_version(Elf_Shdr *sechdrs,
972 unsigned int versindex,
975 const unsigned long *crc)
980 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
981 unsigned int versindex,
987 static inline int same_magic(const char *amagic, const char *bmagic,
990 return strcmp(amagic, bmagic) == 0;
992 #endif /* CONFIG_MODVERSIONS */
994 /* Resolve a symbol for this module. I.e. if we find one, record usage.
995 Must be holding module_mutex. */
996 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
997 unsigned int versindex,
1001 struct module *owner;
1003 const unsigned long *crc;
1005 ret = find_symbol(name, &owner, &crc,
1006 !(mod->taints & TAINT_PROPRIETARY_MODULE), true);
1007 if (!IS_ERR_VALUE(ret)) {
1008 /* use_module can fail due to OOM,
1009 or module initialization or unloading */
1010 if (!check_version(sechdrs, versindex, name, mod, crc) ||
1011 !use_module(mod, owner))
1018 * /sys/module/foo/sections stuff
1019 * J. Corbet <corbet@lwn.net>
1021 #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1022 struct module_sect_attr
1024 struct module_attribute mattr;
1026 unsigned long address;
1029 struct module_sect_attrs
1031 struct attribute_group grp;
1032 unsigned int nsections;
1033 struct module_sect_attr attrs[0];
1036 static ssize_t module_sect_show(struct module_attribute *mattr,
1037 struct module *mod, char *buf)
1039 struct module_sect_attr *sattr =
1040 container_of(mattr, struct module_sect_attr, mattr);
1041 return sprintf(buf, "0x%lx\n", sattr->address);
1044 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1046 unsigned int section;
1048 for (section = 0; section < sect_attrs->nsections; section++)
1049 kfree(sect_attrs->attrs[section].name);
1053 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1054 char *secstrings, Elf_Shdr *sechdrs)
1056 unsigned int nloaded = 0, i, size[2];
1057 struct module_sect_attrs *sect_attrs;
1058 struct module_sect_attr *sattr;
1059 struct attribute **gattr;
1061 /* Count loaded sections and allocate structures */
1062 for (i = 0; i < nsect; i++)
1063 if (sechdrs[i].sh_flags & SHF_ALLOC)
1065 size[0] = ALIGN(sizeof(*sect_attrs)
1066 + nloaded * sizeof(sect_attrs->attrs[0]),
1067 sizeof(sect_attrs->grp.attrs[0]));
1068 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1069 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1070 if (sect_attrs == NULL)
1073 /* Setup section attributes. */
1074 sect_attrs->grp.name = "sections";
1075 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1077 sect_attrs->nsections = 0;
1078 sattr = §_attrs->attrs[0];
1079 gattr = §_attrs->grp.attrs[0];
1080 for (i = 0; i < nsect; i++) {
1081 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1083 sattr->address = sechdrs[i].sh_addr;
1084 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1086 if (sattr->name == NULL)
1088 sect_attrs->nsections++;
1089 sattr->mattr.show = module_sect_show;
1090 sattr->mattr.store = NULL;
1091 sattr->mattr.attr.name = sattr->name;
1092 sattr->mattr.attr.mode = S_IRUGO;
1093 *(gattr++) = &(sattr++)->mattr.attr;
1097 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1100 mod->sect_attrs = sect_attrs;
1103 free_sect_attrs(sect_attrs);
1106 static void remove_sect_attrs(struct module *mod)
1108 if (mod->sect_attrs) {
1109 sysfs_remove_group(&mod->mkobj.kobj,
1110 &mod->sect_attrs->grp);
1111 /* We are positive that no one is using any sect attrs
1112 * at this point. Deallocate immediately. */
1113 free_sect_attrs(mod->sect_attrs);
1114 mod->sect_attrs = NULL;
1119 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1122 struct module_notes_attrs {
1123 struct kobject *dir;
1125 struct bin_attribute attrs[0];
1128 static ssize_t module_notes_read(struct kobject *kobj,
1129 struct bin_attribute *bin_attr,
1130 char *buf, loff_t pos, size_t count)
1133 * The caller checked the pos and count against our size.
1135 memcpy(buf, bin_attr->private + pos, count);
1139 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1142 if (notes_attrs->dir) {
1144 sysfs_remove_bin_file(notes_attrs->dir,
1145 ¬es_attrs->attrs[i]);
1146 kobject_del(notes_attrs->dir);
1151 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1152 char *secstrings, Elf_Shdr *sechdrs)
1154 unsigned int notes, loaded, i;
1155 struct module_notes_attrs *notes_attrs;
1156 struct bin_attribute *nattr;
1158 /* Count notes sections and allocate structures. */
1160 for (i = 0; i < nsect; i++)
1161 if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
1162 (sechdrs[i].sh_type == SHT_NOTE))
1168 notes_attrs = kzalloc(sizeof(*notes_attrs)
1169 + notes * sizeof(notes_attrs->attrs[0]),
1171 if (notes_attrs == NULL)
1174 notes_attrs->notes = notes;
1175 nattr = ¬es_attrs->attrs[0];
1176 for (loaded = i = 0; i < nsect; ++i) {
1177 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1179 if (sechdrs[i].sh_type == SHT_NOTE) {
1180 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1181 nattr->attr.mode = S_IRUGO;
1182 nattr->size = sechdrs[i].sh_size;
1183 nattr->private = (void *) sechdrs[i].sh_addr;
1184 nattr->read = module_notes_read;
1190 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1191 if (!notes_attrs->dir)
1194 for (i = 0; i < notes; ++i)
1195 if (sysfs_create_bin_file(notes_attrs->dir,
1196 ¬es_attrs->attrs[i]))
1199 mod->notes_attrs = notes_attrs;
1203 free_notes_attrs(notes_attrs, i);
1206 static void remove_notes_attrs(struct module *mod)
1208 if (mod->notes_attrs)
1209 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1214 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1215 char *sectstrings, Elf_Shdr *sechdrs)
1219 static inline void remove_sect_attrs(struct module *mod)
1223 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1224 char *sectstrings, Elf_Shdr *sechdrs)
1228 static inline void remove_notes_attrs(struct module *mod)
1234 int module_add_modinfo_attrs(struct module *mod)
1236 struct module_attribute *attr;
1237 struct module_attribute *temp_attr;
1241 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1242 (ARRAY_SIZE(modinfo_attrs) + 1)),
1244 if (!mod->modinfo_attrs)
1247 temp_attr = mod->modinfo_attrs;
1248 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1250 (attr->test && attr->test(mod))) {
1251 memcpy(temp_attr, attr, sizeof(*temp_attr));
1252 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1259 void module_remove_modinfo_attrs(struct module *mod)
1261 struct module_attribute *attr;
1264 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1265 /* pick a field to test for end of list */
1266 if (!attr->attr.name)
1268 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1272 kfree(mod->modinfo_attrs);
1275 int mod_sysfs_init(struct module *mod)
1278 struct kobject *kobj;
1280 if (!module_sysfs_initialized) {
1281 printk(KERN_ERR "%s: module sysfs not initialized\n",
1287 kobj = kset_find_obj(module_kset, mod->name);
1289 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1295 mod->mkobj.mod = mod;
1297 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1298 mod->mkobj.kobj.kset = module_kset;
1299 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1302 kobject_put(&mod->mkobj.kobj);
1304 /* delay uevent until full sysfs population */
1309 int mod_sysfs_setup(struct module *mod,
1310 struct kernel_param *kparam,
1311 unsigned int num_params)
1315 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1316 if (!mod->holders_dir) {
1321 err = module_param_sysfs_setup(mod, kparam, num_params);
1323 goto out_unreg_holders;
1325 err = module_add_modinfo_attrs(mod);
1327 goto out_unreg_param;
1329 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1333 module_param_sysfs_remove(mod);
1335 kobject_put(mod->holders_dir);
1337 kobject_put(&mod->mkobj.kobj);
1342 static void mod_kobject_remove(struct module *mod)
1344 module_remove_modinfo_attrs(mod);
1345 module_param_sysfs_remove(mod);
1346 kobject_put(mod->mkobj.drivers_dir);
1347 kobject_put(mod->holders_dir);
1348 kobject_put(&mod->mkobj.kobj);
1352 * link the module with the whole machine is stopped with interrupts off
1353 * - this defends against kallsyms not taking locks
1355 static int __link_module(void *_mod)
1357 struct module *mod = _mod;
1358 list_add(&mod->list, &modules);
1363 * unlink the module with the whole machine is stopped with interrupts off
1364 * - this defends against kallsyms not taking locks
1366 static int __unlink_module(void *_mod)
1368 struct module *mod = _mod;
1369 list_del(&mod->list);
1373 /* Free a module, remove from lists, etc (must hold module_mutex). */
1374 static void free_module(struct module *mod)
1376 /* Delete from various lists */
1377 stop_machine_run(__unlink_module, mod, NR_CPUS);
1378 remove_notes_attrs(mod);
1379 remove_sect_attrs(mod);
1380 mod_kobject_remove(mod);
1382 unwind_remove_table(mod->unwind_info, 0);
1384 /* Arch-specific cleanup. */
1385 module_arch_cleanup(mod);
1387 /* Module unload stuff */
1388 module_unload_free(mod);
1390 /* This may be NULL, but that's OK */
1391 module_free(mod, mod->module_init);
1394 percpu_modfree(mod->percpu);
1396 /* Free lock-classes: */
1397 lockdep_free_key_range(mod->module_core, mod->core_size);
1399 /* Finally, free the core (containing the module structure) */
1400 module_free(mod, mod->module_core);
1403 void *__symbol_get(const char *symbol)
1405 struct module *owner;
1406 unsigned long value;
1409 value = find_symbol(symbol, &owner, NULL, true, true);
1410 if (IS_ERR_VALUE(value))
1412 else if (strong_try_module_get(owner))
1416 return (void *)value;
1418 EXPORT_SYMBOL_GPL(__symbol_get);
1421 * Ensure that an exported symbol [global namespace] does not already exist
1422 * in the kernel or in some other module's exported symbol table.
1424 static int verify_export_symbols(struct module *mod)
1427 struct module *owner;
1428 const struct kernel_symbol *s;
1430 const struct kernel_symbol *sym;
1433 { mod->syms, mod->num_syms },
1434 { mod->gpl_syms, mod->num_gpl_syms },
1435 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1436 { mod->unused_syms, mod->num_unused_syms },
1437 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1440 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1441 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1442 if (!IS_ERR_VALUE(find_symbol(s->name, &owner,
1443 NULL, true, false))) {
1445 "%s: exports duplicate symbol %s"
1447 mod->name, s->name, module_name(owner));
1455 /* Change all symbols so that st_value encodes the pointer directly. */
1456 static int simplify_symbols(Elf_Shdr *sechdrs,
1457 unsigned int symindex,
1459 unsigned int versindex,
1460 unsigned int pcpuindex,
1463 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1464 unsigned long secbase;
1465 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1468 for (i = 1; i < n; i++) {
1469 switch (sym[i].st_shndx) {
1471 /* We compiled with -fno-common. These are not
1472 supposed to happen. */
1473 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1474 printk("%s: please compile with -fno-common\n",
1480 /* Don't need to do anything */
1481 DEBUGP("Absolute symbol: 0x%08lx\n",
1482 (long)sym[i].st_value);
1487 = resolve_symbol(sechdrs, versindex,
1488 strtab + sym[i].st_name, mod);
1490 /* Ok if resolved. */
1491 if (!IS_ERR_VALUE(sym[i].st_value))
1494 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1497 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1498 mod->name, strtab + sym[i].st_name);
1503 /* Divert to percpu allocation if a percpu var. */
1504 if (sym[i].st_shndx == pcpuindex)
1505 secbase = (unsigned long)mod->percpu;
1507 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1508 sym[i].st_value += secbase;
1516 /* Update size with this section: return offset. */
1517 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
1521 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1522 *size = ret + sechdr->sh_size;
1526 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1527 might -- code, read-only data, read-write data, small data. Tally
1528 sizes, and place the offsets into sh_entsize fields: high bit means it
1530 static void layout_sections(struct module *mod,
1531 const Elf_Ehdr *hdr,
1533 const char *secstrings)
1535 static unsigned long const masks[][2] = {
1536 /* NOTE: all executable code must be the first section
1537 * in this array; otherwise modify the text_size
1538 * finder in the two loops below */
1539 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1540 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1541 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1542 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1546 for (i = 0; i < hdr->e_shnum; i++)
1547 sechdrs[i].sh_entsize = ~0UL;
1549 DEBUGP("Core section allocation order:\n");
1550 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1551 for (i = 0; i < hdr->e_shnum; ++i) {
1552 Elf_Shdr *s = &sechdrs[i];
1554 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1555 || (s->sh_flags & masks[m][1])
1556 || s->sh_entsize != ~0UL
1557 || strncmp(secstrings + s->sh_name,
1560 s->sh_entsize = get_offset(&mod->core_size, s);
1561 DEBUGP("\t%s\n", secstrings + s->sh_name);
1564 mod->core_text_size = mod->core_size;
1567 DEBUGP("Init section allocation order:\n");
1568 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1569 for (i = 0; i < hdr->e_shnum; ++i) {
1570 Elf_Shdr *s = &sechdrs[i];
1572 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1573 || (s->sh_flags & masks[m][1])
1574 || s->sh_entsize != ~0UL
1575 || strncmp(secstrings + s->sh_name,
1578 s->sh_entsize = (get_offset(&mod->init_size, s)
1579 | INIT_OFFSET_MASK);
1580 DEBUGP("\t%s\n", secstrings + s->sh_name);
1583 mod->init_text_size = mod->init_size;
1587 static void set_license(struct module *mod, const char *license)
1590 license = "unspecified";
1592 if (!license_is_gpl_compatible(license)) {
1593 if (!(tainted & TAINT_PROPRIETARY_MODULE))
1594 printk(KERN_WARNING "%s: module license '%s' taints "
1595 "kernel.\n", mod->name, license);
1596 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1600 /* Parse tag=value strings from .modinfo section */
1601 static char *next_string(char *string, unsigned long *secsize)
1603 /* Skip non-zero chars */
1606 if ((*secsize)-- <= 1)
1610 /* Skip any zero padding. */
1611 while (!string[0]) {
1613 if ((*secsize)-- <= 1)
1619 static char *get_modinfo(Elf_Shdr *sechdrs,
1624 unsigned int taglen = strlen(tag);
1625 unsigned long size = sechdrs[info].sh_size;
1627 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1628 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1629 return p + taglen + 1;
1634 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1635 unsigned int infoindex)
1637 struct module_attribute *attr;
1640 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1643 get_modinfo(sechdrs,
1649 #ifdef CONFIG_KALLSYMS
1650 static int is_exported(const char *name, const struct module *mod)
1652 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1655 if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1662 static char elf_type(const Elf_Sym *sym,
1664 const char *secstrings,
1667 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1668 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1673 if (sym->st_shndx == SHN_UNDEF)
1675 if (sym->st_shndx == SHN_ABS)
1677 if (sym->st_shndx >= SHN_LORESERVE)
1679 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1681 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1682 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1683 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1685 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1690 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1691 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1696 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1697 ".debug", strlen(".debug")) == 0)
1702 static void add_kallsyms(struct module *mod,
1704 unsigned int symindex,
1705 unsigned int strindex,
1706 const char *secstrings)
1710 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1711 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1712 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1714 /* Set types up while we still have access to sections. */
1715 for (i = 0; i < mod->num_symtab; i++)
1716 mod->symtab[i].st_info
1717 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1720 static inline void add_kallsyms(struct module *mod,
1722 unsigned int symindex,
1723 unsigned int strindex,
1724 const char *secstrings)
1727 #endif /* CONFIG_KALLSYMS */
1729 /* Allocate and load the module: note that size of section 0 is always
1730 zero, and we rely on this for optional sections. */
1731 static struct module *load_module(void __user *umod,
1733 const char __user *uargs)
1737 char *secstrings, *args, *modmagic, *strtab = NULL;
1739 unsigned int symindex = 0;
1740 unsigned int strindex = 0;
1741 unsigned int setupindex;
1742 unsigned int exindex;
1743 unsigned int exportindex;
1744 unsigned int modindex;
1745 unsigned int obsparmindex;
1746 unsigned int infoindex;
1747 unsigned int gplindex;
1748 unsigned int crcindex;
1749 unsigned int gplcrcindex;
1750 unsigned int versindex;
1751 unsigned int pcpuindex;
1752 unsigned int gplfutureindex;
1753 unsigned int gplfuturecrcindex;
1754 unsigned int unwindex = 0;
1755 unsigned int unusedindex;
1756 unsigned int unusedcrcindex;
1757 unsigned int unusedgplindex;
1758 unsigned int unusedgplcrcindex;
1759 unsigned int markersindex;
1760 unsigned int markersstringsindex;
1763 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1764 struct exception_table_entry *extable;
1765 mm_segment_t old_fs;
1767 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1769 if (len < sizeof(*hdr))
1770 return ERR_PTR(-ENOEXEC);
1772 /* Suck in entire file: we'll want most of it. */
1773 /* vmalloc barfs on "unusual" numbers. Check here */
1774 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1775 return ERR_PTR(-ENOMEM);
1776 if (copy_from_user(hdr, umod, len) != 0) {
1781 /* Sanity checks against insmoding binaries or wrong arch,
1782 weird elf version */
1783 if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
1784 || hdr->e_type != ET_REL
1785 || !elf_check_arch(hdr)
1786 || hdr->e_shentsize != sizeof(*sechdrs)) {
1791 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1794 /* Convenience variables */
1795 sechdrs = (void *)hdr + hdr->e_shoff;
1796 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1797 sechdrs[0].sh_addr = 0;
1799 for (i = 1; i < hdr->e_shnum; i++) {
1800 if (sechdrs[i].sh_type != SHT_NOBITS
1801 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1804 /* Mark all sections sh_addr with their address in the
1806 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1808 /* Internal symbols and strings. */
1809 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1811 strindex = sechdrs[i].sh_link;
1812 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1814 #ifndef CONFIG_MODULE_UNLOAD
1815 /* Don't load .exit sections */
1816 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1817 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1821 modindex = find_sec(hdr, sechdrs, secstrings,
1822 ".gnu.linkonce.this_module");
1824 printk(KERN_WARNING "No module found in object\n");
1828 mod = (void *)sechdrs[modindex].sh_addr;
1830 if (symindex == 0) {
1831 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1837 /* Optional sections */
1838 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1839 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1840 gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1841 unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
1842 unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
1843 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1844 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1845 gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1846 unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
1847 unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
1848 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1849 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1850 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1851 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1852 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1853 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1854 #ifdef ARCH_UNWIND_SECTION_NAME
1855 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1858 /* Don't keep modinfo and version sections. */
1859 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1860 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1861 #ifdef CONFIG_KALLSYMS
1862 /* Keep symbol and string tables for decoding later. */
1863 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1864 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1867 sechdrs[unwindex].sh_flags |= SHF_ALLOC;
1869 /* Check module struct version now, before we try to use module. */
1870 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1875 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1876 /* This is allowed: modprobe --force will invalidate it. */
1878 err = try_to_force_load(mod, "magic");
1881 } else if (!same_magic(modmagic, vermagic, versindex)) {
1882 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1883 mod->name, modmagic, vermagic);
1888 /* Now copy in args */
1889 args = strndup_user(uargs, ~0UL >> 1);
1891 err = PTR_ERR(args);
1895 if (find_module(mod->name)) {
1900 mod->state = MODULE_STATE_COMING;
1902 /* Allow arches to frob section contents and sizes. */
1903 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1908 /* We have a special allocation for this section. */
1909 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1910 sechdrs[pcpuindex].sh_addralign,
1916 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1917 mod->percpu = percpu;
1920 /* Determine total sizes, and put offsets in sh_entsize. For now
1921 this is done generically; there doesn't appear to be any
1922 special cases for the architectures. */
1923 layout_sections(mod, hdr, sechdrs, secstrings);
1925 /* Do the allocs. */
1926 ptr = module_alloc(mod->core_size);
1931 memset(ptr, 0, mod->core_size);
1932 mod->module_core = ptr;
1934 ptr = module_alloc(mod->init_size);
1935 if (!ptr && mod->init_size) {
1939 memset(ptr, 0, mod->init_size);
1940 mod->module_init = ptr;
1942 /* Transfer each section which specifies SHF_ALLOC */
1943 DEBUGP("final section addresses:\n");
1944 for (i = 0; i < hdr->e_shnum; i++) {
1947 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1950 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
1951 dest = mod->module_init
1952 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
1954 dest = mod->module_core + sechdrs[i].sh_entsize;
1956 if (sechdrs[i].sh_type != SHT_NOBITS)
1957 memcpy(dest, (void *)sechdrs[i].sh_addr,
1958 sechdrs[i].sh_size);
1959 /* Update sh_addr to point to copy in image. */
1960 sechdrs[i].sh_addr = (unsigned long)dest;
1961 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
1963 /* Module has been moved. */
1964 mod = (void *)sechdrs[modindex].sh_addr;
1966 /* Now we've moved module, initialize linked lists, etc. */
1967 module_unload_init(mod);
1969 /* add kobject, so we can reference it. */
1970 err = mod_sysfs_init(mod);
1974 /* Set up license info based on the info section */
1975 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
1978 * ndiswrapper is under GPL by itself, but loads proprietary modules.
1979 * Don't use add_taint_module(), as it would prevent ndiswrapper from
1980 * using GPL-only symbols it needs.
1982 if (strcmp(mod->name, "ndiswrapper") == 0)
1983 add_taint(TAINT_PROPRIETARY_MODULE);
1985 /* driverloader was caught wrongly pretending to be under GPL */
1986 if (strcmp(mod->name, "driverloader") == 0)
1987 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1989 /* Set up MODINFO_ATTR fields */
1990 setup_modinfo(mod, sechdrs, infoindex);
1992 /* Fix up syms, so that st_value is a pointer to location. */
1993 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
1998 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
1999 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
2000 mod->syms = (void *)sechdrs[exportindex].sh_addr;
2002 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
2003 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
2004 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
2006 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
2007 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
2008 sizeof(*mod->gpl_future_syms);
2009 mod->num_unused_syms = sechdrs[unusedindex].sh_size /
2010 sizeof(*mod->unused_syms);
2011 mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
2012 sizeof(*mod->unused_gpl_syms);
2013 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
2014 if (gplfuturecrcindex)
2015 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
2017 mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
2019 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
2020 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
2021 if (unusedgplcrcindex)
2022 mod->unused_gpl_crcs
2023 = (void *)sechdrs[unusedgplcrcindex].sh_addr;
2025 #ifdef CONFIG_MODVERSIONS
2026 if ((mod->num_syms && !crcindex) ||
2027 (mod->num_gpl_syms && !gplcrcindex) ||
2028 (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
2029 (mod->num_unused_syms && !unusedcrcindex) ||
2030 (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
2031 printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name);
2032 err = try_to_force_load(mod, "nocrc");
2037 markersindex = find_sec(hdr, sechdrs, secstrings, "__markers");
2038 markersstringsindex = find_sec(hdr, sechdrs, secstrings,
2039 "__markers_strings");
2041 /* Now do relocations. */
2042 for (i = 1; i < hdr->e_shnum; i++) {
2043 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2044 unsigned int info = sechdrs[i].sh_info;
2046 /* Not a valid relocation section? */
2047 if (info >= hdr->e_shnum)
2050 /* Don't bother with non-allocated sections */
2051 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2054 if (sechdrs[i].sh_type == SHT_REL)
2055 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2056 else if (sechdrs[i].sh_type == SHT_RELA)
2057 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2062 #ifdef CONFIG_MARKERS
2063 mod->markers = (void *)sechdrs[markersindex].sh_addr;
2065 sechdrs[markersindex].sh_size / sizeof(*mod->markers);
2068 /* Find duplicate symbols */
2069 err = verify_export_symbols(mod);
2074 /* Set up and sort exception table */
2075 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
2076 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
2077 sort_extable(extable, extable + mod->num_exentries);
2079 /* Finally, copy percpu area over. */
2080 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
2081 sechdrs[pcpuindex].sh_size);
2083 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
2085 #ifdef CONFIG_MARKERS
2087 marker_update_probe_range(mod->markers,
2088 mod->markers + mod->num_markers);
2090 err = module_finalize(hdr, sechdrs, mod);
2094 /* flush the icache in correct context */
2099 * Flush the instruction cache, since we've played with text.
2100 * Do it before processing of module parameters, so the module
2101 * can provide parameter accessor functions of its own.
2103 if (mod->module_init)
2104 flush_icache_range((unsigned long)mod->module_init,
2105 (unsigned long)mod->module_init
2107 flush_icache_range((unsigned long)mod->module_core,
2108 (unsigned long)mod->module_core + mod->core_size);
2114 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2117 /* Now sew it into the lists so we can get lockdep and oops
2118 * info during argument parsing. Noone should access us, since
2119 * strong_try_module_get() will fail. */
2120 stop_machine_run(__link_module, mod, NR_CPUS);
2122 /* Size of section 0 is 0, so this works well if no params */
2123 err = parse_args(mod->name, mod->args,
2124 (struct kernel_param *)
2125 sechdrs[setupindex].sh_addr,
2126 sechdrs[setupindex].sh_size
2127 / sizeof(struct kernel_param),
2132 err = mod_sysfs_setup(mod,
2133 (struct kernel_param *)
2134 sechdrs[setupindex].sh_addr,
2135 sechdrs[setupindex].sh_size
2136 / sizeof(struct kernel_param));
2139 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2140 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2142 /* Size of section 0 is 0, so this works well if no unwind info. */
2143 mod->unwind_info = unwind_add_table(mod,
2144 (void *)sechdrs[unwindex].sh_addr,
2145 sechdrs[unwindex].sh_size);
2147 /* Get rid of temporary copy */
2154 stop_machine_run(__unlink_module, mod, NR_CPUS);
2155 module_arch_cleanup(mod);
2157 kobject_del(&mod->mkobj.kobj);
2158 kobject_put(&mod->mkobj.kobj);
2160 module_unload_free(mod);
2161 module_free(mod, mod->module_init);
2163 module_free(mod, mod->module_core);
2166 percpu_modfree(percpu);
2171 return ERR_PTR(err);
2174 printk(KERN_ERR "Module len %lu truncated\n", len);
2179 /* This is where the real work happens */
2181 sys_init_module(void __user *umod,
2183 const char __user *uargs)
2188 /* Must have permission */
2189 if (!capable(CAP_SYS_MODULE))
2192 /* Only one module load at a time, please */
2193 if (mutex_lock_interruptible(&module_mutex) != 0)
2196 /* Do all the hard work */
2197 mod = load_module(umod, len, uargs);
2199 mutex_unlock(&module_mutex);
2200 return PTR_ERR(mod);
2203 /* Drop lock so they can recurse */
2204 mutex_unlock(&module_mutex);
2206 blocking_notifier_call_chain(&module_notify_list,
2207 MODULE_STATE_COMING, mod);
2209 /* Start the module */
2210 if (mod->init != NULL)
2213 /* Init routine failed: abort. Try to protect us from
2214 buggy refcounters. */
2215 mod->state = MODULE_STATE_GOING;
2216 synchronize_sched();
2218 blocking_notifier_call_chain(&module_notify_list,
2219 MODULE_STATE_GOING, mod);
2220 mutex_lock(&module_mutex);
2222 mutex_unlock(&module_mutex);
2223 wake_up(&module_wq);
2227 printk(KERN_WARNING "%s: '%s'->init suspiciously returned %d, "
2228 "it should follow 0/-E convention\n"
2229 KERN_WARNING "%s: loading module anyway...\n",
2230 __func__, mod->name, ret,
2235 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2236 mod->state = MODULE_STATE_LIVE;
2237 wake_up(&module_wq);
2239 mutex_lock(&module_mutex);
2240 /* Drop initial reference. */
2242 unwind_remove_table(mod->unwind_info, 1);
2243 module_free(mod, mod->module_init);
2244 mod->module_init = NULL;
2246 mod->init_text_size = 0;
2247 mutex_unlock(&module_mutex);
2252 static inline int within(unsigned long addr, void *start, unsigned long size)
2254 return ((void *)addr >= start && (void *)addr < start + size);
2257 #ifdef CONFIG_KALLSYMS
2259 * This ignores the intensely annoying "mapping symbols" found
2260 * in ARM ELF files: $a, $t and $d.
2262 static inline int is_arm_mapping_symbol(const char *str)
2264 return str[0] == '$' && strchr("atd", str[1])
2265 && (str[2] == '\0' || str[2] == '.');
2268 static const char *get_ksymbol(struct module *mod,
2270 unsigned long *size,
2271 unsigned long *offset)
2273 unsigned int i, best = 0;
2274 unsigned long nextval;
2276 /* At worse, next value is at end of module */
2277 if (within(addr, mod->module_init, mod->init_size))
2278 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2280 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2282 /* Scan for closest preceeding symbol, and next symbol. (ELF
2283 starts real symbols at 1). */
2284 for (i = 1; i < mod->num_symtab; i++) {
2285 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2288 /* We ignore unnamed symbols: they're uninformative
2289 * and inserted at a whim. */
2290 if (mod->symtab[i].st_value <= addr
2291 && mod->symtab[i].st_value > mod->symtab[best].st_value
2292 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2293 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2295 if (mod->symtab[i].st_value > addr
2296 && mod->symtab[i].st_value < nextval
2297 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2298 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2299 nextval = mod->symtab[i].st_value;
2306 *size = nextval - mod->symtab[best].st_value;
2308 *offset = addr - mod->symtab[best].st_value;
2309 return mod->strtab + mod->symtab[best].st_name;
2312 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2313 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2314 const char *module_address_lookup(unsigned long addr,
2315 unsigned long *size,
2316 unsigned long *offset,
2321 const char *ret = NULL;
2324 list_for_each_entry(mod, &modules, list) {
2325 if (within(addr, mod->module_init, mod->init_size)
2326 || within(addr, mod->module_core, mod->core_size)) {
2328 *modname = mod->name;
2329 ret = get_ksymbol(mod, addr, size, offset);
2333 /* Make a copy in here where it's safe */
2335 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2342 int lookup_module_symbol_name(unsigned long addr, char *symname)
2347 list_for_each_entry(mod, &modules, list) {
2348 if (within(addr, mod->module_init, mod->init_size) ||
2349 within(addr, mod->module_core, mod->core_size)) {
2352 sym = get_ksymbol(mod, addr, NULL, NULL);
2355 strlcpy(symname, sym, KSYM_NAME_LEN);
2365 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2366 unsigned long *offset, char *modname, char *name)
2371 list_for_each_entry(mod, &modules, list) {
2372 if (within(addr, mod->module_init, mod->init_size) ||
2373 within(addr, mod->module_core, mod->core_size)) {
2376 sym = get_ksymbol(mod, addr, size, offset);
2380 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2382 strlcpy(name, sym, KSYM_NAME_LEN);
2392 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2393 char *name, char *module_name, int *exported)
2398 list_for_each_entry(mod, &modules, list) {
2399 if (symnum < mod->num_symtab) {
2400 *value = mod->symtab[symnum].st_value;
2401 *type = mod->symtab[symnum].st_info;
2402 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2404 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2405 *exported = is_exported(name, mod);
2409 symnum -= mod->num_symtab;
2415 static unsigned long mod_find_symname(struct module *mod, const char *name)
2419 for (i = 0; i < mod->num_symtab; i++)
2420 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2421 mod->symtab[i].st_info != 'U')
2422 return mod->symtab[i].st_value;
2426 /* Look for this name: can be of form module:name. */
2427 unsigned long module_kallsyms_lookup_name(const char *name)
2431 unsigned long ret = 0;
2433 /* Don't lock: we're in enough trouble already. */
2435 if ((colon = strchr(name, ':')) != NULL) {
2437 if ((mod = find_module(name)) != NULL)
2438 ret = mod_find_symname(mod, colon+1);
2441 list_for_each_entry(mod, &modules, list)
2442 if ((ret = mod_find_symname(mod, name)) != 0)
2448 #endif /* CONFIG_KALLSYMS */
2450 /* Called by the /proc file system to return a list of modules. */
2451 static void *m_start(struct seq_file *m, loff_t *pos)
2453 mutex_lock(&module_mutex);
2454 return seq_list_start(&modules, *pos);
2457 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2459 return seq_list_next(p, &modules, pos);
2462 static void m_stop(struct seq_file *m, void *p)
2464 mutex_unlock(&module_mutex);
2467 static char *module_flags(struct module *mod, char *buf)
2472 mod->state == MODULE_STATE_GOING ||
2473 mod->state == MODULE_STATE_COMING) {
2475 if (mod->taints & TAINT_PROPRIETARY_MODULE)
2477 if (mod->taints & TAINT_FORCED_MODULE)
2480 * TAINT_FORCED_RMMOD: could be added.
2481 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2485 /* Show a - for module-is-being-unloaded */
2486 if (mod->state == MODULE_STATE_GOING)
2488 /* Show a + for module-is-being-loaded */
2489 if (mod->state == MODULE_STATE_COMING)
2498 static int m_show(struct seq_file *m, void *p)
2500 struct module *mod = list_entry(p, struct module, list);
2503 seq_printf(m, "%s %lu",
2504 mod->name, mod->init_size + mod->core_size);
2505 print_unload_info(m, mod);
2507 /* Informative for users. */
2508 seq_printf(m, " %s",
2509 mod->state == MODULE_STATE_GOING ? "Unloading":
2510 mod->state == MODULE_STATE_COMING ? "Loading":
2512 /* Used by oprofile and other similar tools. */
2513 seq_printf(m, " 0x%p", mod->module_core);
2517 seq_printf(m, " %s", module_flags(mod, buf));
2519 seq_printf(m, "\n");
2523 /* Format: modulename size refcount deps address
2525 Where refcount is a number or -, and deps is a comma-separated list
2528 const struct seq_operations modules_op = {
2535 /* Given an address, look for it in the module exception tables. */
2536 const struct exception_table_entry *search_module_extables(unsigned long addr)
2538 const struct exception_table_entry *e = NULL;
2542 list_for_each_entry(mod, &modules, list) {
2543 if (mod->num_exentries == 0)
2546 e = search_extable(mod->extable,
2547 mod->extable + mod->num_exentries - 1,
2554 /* Now, if we found one, we are running inside it now, hence
2555 we cannot unload the module, hence no refcnt needed. */
2560 * Is this a valid module address?
2562 int is_module_address(unsigned long addr)
2568 list_for_each_entry(mod, &modules, list) {
2569 if (within(addr, mod->module_core, mod->core_size)) {
2581 /* Is this a valid kernel address? */
2582 struct module *__module_text_address(unsigned long addr)
2586 list_for_each_entry(mod, &modules, list)
2587 if (within(addr, mod->module_init, mod->init_text_size)
2588 || within(addr, mod->module_core, mod->core_text_size))
2593 struct module *module_text_address(unsigned long addr)
2598 mod = __module_text_address(addr);
2604 /* Don't grab lock, we're oopsing. */
2605 void print_modules(void)
2610 printk("Modules linked in:");
2611 list_for_each_entry(mod, &modules, list)
2612 printk(" %s%s", mod->name, module_flags(mod, buf));
2613 if (last_unloaded_module[0])
2614 printk(" [last unloaded: %s]", last_unloaded_module);
2618 #ifdef CONFIG_MODVERSIONS
2619 /* Generate the signature for struct module here, too, for modversions. */
2620 void struct_module(struct module *mod) { return; }
2621 EXPORT_SYMBOL(struct_module);
2624 #ifdef CONFIG_MARKERS
2625 void module_update_markers(void)
2629 mutex_lock(&module_mutex);
2630 list_for_each_entry(mod, &modules, list)
2632 marker_update_probe_range(mod->markers,
2633 mod->markers + mod->num_markers);
2634 mutex_unlock(&module_mutex);