1 /* Rewritten by Rusty Russell, on the backs of many others...
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/config.h>
20 #include <linux/module.h>
21 #include <linux/moduleloader.h>
22 #include <linux/init.h>
23 #include <linux/kernel.h>
24 #include <linux/slab.h>
25 #include <linux/vmalloc.h>
26 #include <linux/elf.h>
27 #include <linux/seq_file.h>
28 #include <linux/syscalls.h>
29 #include <linux/fcntl.h>
30 #include <linux/rcupdate.h>
31 #include <linux/capability.h>
32 #include <linux/cpu.h>
33 #include <linux/moduleparam.h>
34 #include <linux/errno.h>
35 #include <linux/err.h>
36 #include <linux/vermagic.h>
37 #include <linux/notifier.h>
38 #include <linux/stop_machine.h>
39 #include <linux/device.h>
40 #include <linux/string.h>
41 #include <linux/sched.h>
42 #include <linux/mutex.h>
43 #include <asm/uaccess.h>
44 #include <asm/semaphore.h>
45 #include <asm/cacheflush.h>
50 #define DEBUGP(fmt , a...)
53 #ifndef ARCH_SHF_SMALL
54 #define ARCH_SHF_SMALL 0
57 /* If this is set, the section belongs in the init part of the module */
58 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
60 /* Protects module list */
61 static DEFINE_SPINLOCK(modlist_lock);
63 /* List of modules, protected by module_mutex AND modlist_lock */
64 static DEFINE_MUTEX(module_mutex);
65 static LIST_HEAD(modules);
67 static DEFINE_MUTEX(notify_mutex);
68 static struct notifier_block * module_notify_list;
70 int register_module_notifier(struct notifier_block * nb)
73 mutex_lock(¬ify_mutex);
74 err = notifier_chain_register(&module_notify_list, nb);
75 mutex_unlock(¬ify_mutex);
78 EXPORT_SYMBOL(register_module_notifier);
80 int unregister_module_notifier(struct notifier_block * nb)
83 mutex_lock(¬ify_mutex);
84 err = notifier_chain_unregister(&module_notify_list, nb);
85 mutex_unlock(¬ify_mutex);
88 EXPORT_SYMBOL(unregister_module_notifier);
90 /* We require a truly strong try_module_get() */
91 static inline int strong_try_module_get(struct module *mod)
93 if (mod && mod->state == MODULE_STATE_COMING)
95 return try_module_get(mod);
98 /* A thread that wants to hold a reference to a module only while it
99 * is running can call ths to safely exit.
100 * nfsd and lockd use this.
102 void __module_put_and_exit(struct module *mod, long code)
107 EXPORT_SYMBOL(__module_put_and_exit);
109 /* Find a module section: 0 means not found. */
110 static unsigned int find_sec(Elf_Ehdr *hdr,
112 const char *secstrings,
117 for (i = 1; i < hdr->e_shnum; i++)
118 /* Alloc bit cleared means "ignore it." */
119 if ((sechdrs[i].sh_flags & SHF_ALLOC)
120 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
125 /* Provided by the linker */
126 extern const struct kernel_symbol __start___ksymtab[];
127 extern const struct kernel_symbol __stop___ksymtab[];
128 extern const struct kernel_symbol __start___ksymtab_gpl[];
129 extern const struct kernel_symbol __stop___ksymtab_gpl[];
130 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
131 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
132 extern const unsigned long __start___kcrctab[];
133 extern const unsigned long __start___kcrctab_gpl[];
134 extern const unsigned long __start___kcrctab_gpl_future[];
136 #ifndef CONFIG_MODVERSIONS
137 #define symversion(base, idx) NULL
139 #define symversion(base, idx) ((base) ? ((base) + (idx)) : NULL)
142 /* lookup symbol in given range of kernel_symbols */
143 static const struct kernel_symbol *lookup_symbol(const char *name,
144 const struct kernel_symbol *start,
145 const struct kernel_symbol *stop)
147 const struct kernel_symbol *ks = start;
148 for (; ks < stop; ks++)
149 if (strcmp(ks->name, name) == 0)
154 /* Find a symbol, return value, crc and module which owns it */
155 static unsigned long __find_symbol(const char *name,
156 struct module **owner,
157 const unsigned long **crc,
161 const struct kernel_symbol *ks;
163 /* Core kernel first. */
165 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
167 *crc = symversion(__start___kcrctab, (ks - __start___ksymtab));
171 ks = lookup_symbol(name, __start___ksymtab_gpl,
172 __stop___ksymtab_gpl);
174 *crc = symversion(__start___kcrctab_gpl,
175 (ks - __start___ksymtab_gpl));
179 ks = lookup_symbol(name, __start___ksymtab_gpl_future,
180 __stop___ksymtab_gpl_future);
183 printk(KERN_WARNING "Symbol %s is being used "
184 "by a non-GPL module, which will not "
185 "be allowed in the future\n", name);
186 printk(KERN_WARNING "Please see the file "
187 "Documentation/feature-removal-schedule.txt "
188 "in the kernel source tree for more "
191 *crc = symversion(__start___kcrctab_gpl_future,
192 (ks - __start___ksymtab_gpl_future));
196 /* Now try modules. */
197 list_for_each_entry(mod, &modules, list) {
199 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
201 *crc = symversion(mod->crcs, (ks - mod->syms));
206 ks = lookup_symbol(name, mod->gpl_syms,
207 mod->gpl_syms + mod->num_gpl_syms);
209 *crc = symversion(mod->gpl_crcs,
210 (ks - mod->gpl_syms));
214 ks = lookup_symbol(name, mod->gpl_future_syms,
215 (mod->gpl_future_syms +
216 mod->num_gpl_future_syms));
219 printk(KERN_WARNING "Symbol %s is being used "
220 "by a non-GPL module, which will not "
221 "be allowed in the future\n", name);
222 printk(KERN_WARNING "Please see the file "
223 "Documentation/feature-removal-schedule.txt "
224 "in the kernel source tree for more "
227 *crc = symversion(mod->gpl_future_crcs,
228 (ks - mod->gpl_future_syms));
232 DEBUGP("Failed to find symbol %s\n", name);
236 /* Find a symbol in this elf symbol table */
237 static unsigned long find_local_symbol(Elf_Shdr *sechdrs,
238 unsigned int symindex,
243 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
245 /* Search (defined) internal symbols first. */
246 for (i = 1; i < sechdrs[symindex].sh_size/sizeof(*sym); i++) {
247 if (sym[i].st_shndx != SHN_UNDEF
248 && strcmp(name, strtab + sym[i].st_name) == 0)
249 return sym[i].st_value;
254 /* Search for module by name: must hold module_mutex. */
255 static struct module *find_module(const char *name)
259 list_for_each_entry(mod, &modules, list) {
260 if (strcmp(mod->name, name) == 0)
267 /* Number of blocks used and allocated. */
268 static unsigned int pcpu_num_used, pcpu_num_allocated;
269 /* Size of each block. -ve means used. */
270 static int *pcpu_size;
272 static int split_block(unsigned int i, unsigned short size)
274 /* Reallocation required? */
275 if (pcpu_num_used + 1 > pcpu_num_allocated) {
276 int *new = kmalloc(sizeof(new[0]) * pcpu_num_allocated*2,
281 memcpy(new, pcpu_size, sizeof(new[0])*pcpu_num_allocated);
282 pcpu_num_allocated *= 2;
287 /* Insert a new subblock */
288 memmove(&pcpu_size[i+1], &pcpu_size[i],
289 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
292 pcpu_size[i+1] -= size;
297 static inline unsigned int block_size(int val)
304 /* Created by linker magic */
305 extern char __per_cpu_start[], __per_cpu_end[];
307 static void *percpu_modalloc(unsigned long size, unsigned long align,
314 if (align > SMP_CACHE_BYTES) {
315 printk(KERN_WARNING "%s: per-cpu alignment %li > %i\n",
316 name, align, SMP_CACHE_BYTES);
317 align = SMP_CACHE_BYTES;
320 ptr = __per_cpu_start;
321 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
322 /* Extra for alignment requirement. */
323 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
324 BUG_ON(i == 0 && extra != 0);
326 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
329 /* Transfer extra to previous block. */
330 if (pcpu_size[i-1] < 0)
331 pcpu_size[i-1] -= extra;
333 pcpu_size[i-1] += extra;
334 pcpu_size[i] -= extra;
337 /* Split block if warranted */
338 if (pcpu_size[i] - size > sizeof(unsigned long))
339 if (!split_block(i, size))
343 pcpu_size[i] = -pcpu_size[i];
347 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
352 static void percpu_modfree(void *freeme)
355 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
357 /* First entry is core kernel percpu data. */
358 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
360 pcpu_size[i] = -pcpu_size[i];
367 /* Merge with previous? */
368 if (pcpu_size[i-1] >= 0) {
369 pcpu_size[i-1] += pcpu_size[i];
371 memmove(&pcpu_size[i], &pcpu_size[i+1],
372 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
375 /* Merge with next? */
376 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
377 pcpu_size[i] += pcpu_size[i+1];
379 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
380 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
384 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
386 const char *secstrings)
388 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
391 static int percpu_modinit(void)
394 pcpu_num_allocated = 2;
395 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
397 /* Static in-kernel percpu data (used). */
398 pcpu_size[0] = -ALIGN(__per_cpu_end-__per_cpu_start, SMP_CACHE_BYTES);
400 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
401 if (pcpu_size[1] < 0) {
402 printk(KERN_ERR "No per-cpu room for modules.\n");
408 __initcall(percpu_modinit);
409 #else /* ... !CONFIG_SMP */
410 static inline void *percpu_modalloc(unsigned long size, unsigned long align,
415 static inline void percpu_modfree(void *pcpuptr)
419 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
421 const char *secstrings)
425 static inline void percpu_modcopy(void *pcpudst, const void *src,
428 /* pcpusec should be 0, and size of that section should be 0. */
431 #endif /* CONFIG_SMP */
433 #define MODINFO_ATTR(field) \
434 static void setup_modinfo_##field(struct module *mod, const char *s) \
436 mod->field = kstrdup(s, GFP_KERNEL); \
438 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
439 struct module *mod, char *buffer) \
441 return sprintf(buffer, "%s\n", mod->field); \
443 static int modinfo_##field##_exists(struct module *mod) \
445 return mod->field != NULL; \
447 static void free_modinfo_##field(struct module *mod) \
452 static struct module_attribute modinfo_##field = { \
453 .attr = { .name = __stringify(field), .mode = 0444, \
454 .owner = THIS_MODULE }, \
455 .show = show_modinfo_##field, \
456 .setup = setup_modinfo_##field, \
457 .test = modinfo_##field##_exists, \
458 .free = free_modinfo_##field, \
461 MODINFO_ATTR(version);
462 MODINFO_ATTR(srcversion);
464 #ifdef CONFIG_MODULE_UNLOAD
465 /* Init the unload section of the module. */
466 static void module_unload_init(struct module *mod)
470 INIT_LIST_HEAD(&mod->modules_which_use_me);
471 for (i = 0; i < NR_CPUS; i++)
472 local_set(&mod->ref[i].count, 0);
473 /* Hold reference count during initialization. */
474 local_set(&mod->ref[raw_smp_processor_id()].count, 1);
475 /* Backwards compatibility macros put refcount during init. */
476 mod->waiter = current;
479 /* modules using other modules */
482 struct list_head list;
483 struct module *module_which_uses;
486 /* Does a already use b? */
487 static int already_uses(struct module *a, struct module *b)
489 struct module_use *use;
491 list_for_each_entry(use, &b->modules_which_use_me, list) {
492 if (use->module_which_uses == a) {
493 DEBUGP("%s uses %s!\n", a->name, b->name);
497 DEBUGP("%s does not use %s!\n", a->name, b->name);
501 /* Module a uses b */
502 static int use_module(struct module *a, struct module *b)
504 struct module_use *use;
505 if (b == NULL || already_uses(a, b)) return 1;
507 if (!strong_try_module_get(b))
510 DEBUGP("Allocating new usage for %s.\n", a->name);
511 use = kmalloc(sizeof(*use), GFP_ATOMIC);
513 printk("%s: out of memory loading\n", a->name);
518 use->module_which_uses = a;
519 list_add(&use->list, &b->modules_which_use_me);
523 /* Clear the unload stuff of the module. */
524 static void module_unload_free(struct module *mod)
528 list_for_each_entry(i, &modules, list) {
529 struct module_use *use;
531 list_for_each_entry(use, &i->modules_which_use_me, list) {
532 if (use->module_which_uses == mod) {
533 DEBUGP("%s unusing %s\n", mod->name, i->name);
535 list_del(&use->list);
537 /* There can be at most one match. */
544 #ifdef CONFIG_MODULE_FORCE_UNLOAD
545 static inline int try_force_unload(unsigned int flags)
547 int ret = (flags & O_TRUNC);
549 add_taint(TAINT_FORCED_RMMOD);
553 static inline int try_force_unload(unsigned int flags)
557 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
566 /* Whole machine is stopped with interrupts off when this runs. */
567 static int __try_stop_module(void *_sref)
569 struct stopref *sref = _sref;
571 /* If it's not unused, quit unless we are told to block. */
572 if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
573 if (!(*sref->forced = try_force_unload(sref->flags)))
577 /* Mark it as dying. */
578 sref->mod->state = MODULE_STATE_GOING;
582 static int try_stop_module(struct module *mod, int flags, int *forced)
584 struct stopref sref = { mod, flags, forced };
586 return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
589 unsigned int module_refcount(struct module *mod)
591 unsigned int i, total = 0;
593 for (i = 0; i < NR_CPUS; i++)
594 total += local_read(&mod->ref[i].count);
597 EXPORT_SYMBOL(module_refcount);
599 /* This exists whether we can unload or not */
600 static void free_module(struct module *mod);
602 static void wait_for_zero_refcount(struct module *mod)
604 /* Since we might sleep for some time, drop the semaphore first */
605 mutex_unlock(&module_mutex);
607 DEBUGP("Looking at refcount...\n");
608 set_current_state(TASK_UNINTERRUPTIBLE);
609 if (module_refcount(mod) == 0)
613 current->state = TASK_RUNNING;
614 mutex_lock(&module_mutex);
618 sys_delete_module(const char __user *name_user, unsigned int flags)
621 char name[MODULE_NAME_LEN];
624 if (!capable(CAP_SYS_MODULE))
627 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
629 name[MODULE_NAME_LEN-1] = '\0';
631 if (mutex_lock_interruptible(&module_mutex) != 0)
634 mod = find_module(name);
640 if (!list_empty(&mod->modules_which_use_me)) {
641 /* Other modules depend on us: get rid of them first. */
646 /* Doing init or already dying? */
647 if (mod->state != MODULE_STATE_LIVE) {
648 /* FIXME: if (force), slam module count and wake up
650 DEBUGP("%s already dying\n", mod->name);
655 /* If it has an init func, it must have an exit func to unload */
656 if ((mod->init != NULL && mod->exit == NULL)
658 forced = try_force_unload(flags);
660 /* This module can't be removed */
666 /* Set this up before setting mod->state */
667 mod->waiter = current;
669 /* Stop the machine so refcounts can't move and disable module. */
670 ret = try_stop_module(mod, flags, &forced);
674 /* Never wait if forced. */
675 if (!forced && module_refcount(mod) != 0)
676 wait_for_zero_refcount(mod);
678 /* Final destruction now noone is using it. */
679 if (mod->exit != NULL) {
680 mutex_unlock(&module_mutex);
682 mutex_lock(&module_mutex);
687 mutex_unlock(&module_mutex);
691 static void print_unload_info(struct seq_file *m, struct module *mod)
693 struct module_use *use;
694 int printed_something = 0;
696 seq_printf(m, " %u ", module_refcount(mod));
698 /* Always include a trailing , so userspace can differentiate
699 between this and the old multi-field proc format. */
700 list_for_each_entry(use, &mod->modules_which_use_me, list) {
701 printed_something = 1;
702 seq_printf(m, "%s,", use->module_which_uses->name);
706 printed_something = 1;
707 seq_printf(m, "[unsafe],");
710 if (mod->init != NULL && mod->exit == NULL) {
711 printed_something = 1;
712 seq_printf(m, "[permanent],");
715 if (!printed_something)
719 void __symbol_put(const char *symbol)
721 struct module *owner;
723 const unsigned long *crc;
725 spin_lock_irqsave(&modlist_lock, flags);
726 if (!__find_symbol(symbol, &owner, &crc, 1))
729 spin_unlock_irqrestore(&modlist_lock, flags);
731 EXPORT_SYMBOL(__symbol_put);
733 void symbol_put_addr(void *addr)
737 spin_lock_irqsave(&modlist_lock, flags);
738 if (!kernel_text_address((unsigned long)addr))
741 module_put(module_text_address((unsigned long)addr));
742 spin_unlock_irqrestore(&modlist_lock, flags);
744 EXPORT_SYMBOL_GPL(symbol_put_addr);
746 static ssize_t show_refcnt(struct module_attribute *mattr,
747 struct module *mod, char *buffer)
749 /* sysfs holds a reference */
750 return sprintf(buffer, "%u\n", module_refcount(mod)-1);
753 static struct module_attribute refcnt = {
754 .attr = { .name = "refcnt", .mode = 0444, .owner = THIS_MODULE },
758 #else /* !CONFIG_MODULE_UNLOAD */
759 static void print_unload_info(struct seq_file *m, struct module *mod)
761 /* We don't know the usage count, or what modules are using. */
762 seq_printf(m, " - -");
765 static inline void module_unload_free(struct module *mod)
769 static inline int use_module(struct module *a, struct module *b)
771 return strong_try_module_get(b);
774 static inline void module_unload_init(struct module *mod)
777 #endif /* CONFIG_MODULE_UNLOAD */
779 static struct module_attribute *modinfo_attrs[] = {
782 #ifdef CONFIG_MODULE_UNLOAD
788 #ifdef CONFIG_OBSOLETE_MODPARM
789 /* Bounds checking done below */
790 static int obsparm_copy_string(const char *val, struct kernel_param *kp)
792 strcpy(kp->arg, val);
796 static int set_obsolete(const char *val, struct kernel_param *kp)
798 unsigned int min, max;
799 unsigned int size, maxsize;
803 struct obsolete_modparm *obsparm = kp->arg;
806 printk(KERN_ERR "Parameter %s needs an argument\n", kp->name);
810 /* type is: [min[-max]]{b,h,i,l,s} */
812 min = simple_strtol(p, &endp, 10);
813 if (endp == obsparm->type)
815 else if (*endp == '-') {
817 max = simple_strtol(p, &endp, 10);
822 return param_array(kp->name, val, min, max, obsparm->addr,
823 1, param_set_byte, &dummy);
825 return param_array(kp->name, val, min, max, obsparm->addr,
826 sizeof(short), param_set_short, &dummy);
828 return param_array(kp->name, val, min, max, obsparm->addr,
829 sizeof(int), param_set_int, &dummy);
831 return param_array(kp->name, val, min, max, obsparm->addr,
832 sizeof(long), param_set_long, &dummy);
834 return param_array(kp->name, val, min, max, obsparm->addr,
835 sizeof(char *), param_set_charp, &dummy);
838 /* Undocumented: 1-5c50 means 1-5 strings of up to 49 chars,
839 and the decl is "char xxx[5][50];" */
841 maxsize = simple_strtol(p, &endp, 10);
842 /* We check lengths here (yes, this is a hack). */
844 while (p[size = strcspn(p, ",")]) {
851 return param_array(kp->name, val, min, max, obsparm->addr,
852 maxsize, obsparm_copy_string, &dummy);
854 printk(KERN_ERR "Unknown obsolete parameter type %s\n", obsparm->type);
858 "Parameter %s doesn't fit in %u chars.\n", kp->name, maxsize);
862 static int obsolete_params(const char *name,
864 struct obsolete_modparm obsparm[],
867 unsigned int symindex,
870 struct kernel_param *kp;
874 kp = kmalloc(sizeof(kp[0]) * num, GFP_KERNEL);
878 for (i = 0; i < num; i++) {
879 char sym_name[128 + sizeof(MODULE_SYMBOL_PREFIX)];
881 snprintf(sym_name, sizeof(sym_name), "%s%s",
882 MODULE_SYMBOL_PREFIX, obsparm[i].name);
884 kp[i].name = obsparm[i].name;
886 kp[i].set = set_obsolete;
889 = (void *)find_local_symbol(sechdrs, symindex, strtab,
891 if (!obsparm[i].addr) {
892 printk("%s: falsely claims to have parameter %s\n",
893 name, obsparm[i].name);
897 kp[i].arg = &obsparm[i];
900 ret = parse_args(name, args, kp, num, NULL);
906 static int obsolete_params(const char *name,
908 struct obsolete_modparm obsparm[],
911 unsigned int symindex,
915 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
919 #endif /* CONFIG_OBSOLETE_MODPARM */
921 static const char vermagic[] = VERMAGIC_STRING;
923 #ifdef CONFIG_MODVERSIONS
924 static int check_version(Elf_Shdr *sechdrs,
925 unsigned int versindex,
928 const unsigned long *crc)
930 unsigned int i, num_versions;
931 struct modversion_info *versions;
933 /* Exporting module didn't supply crcs? OK, we're already tainted. */
937 versions = (void *) sechdrs[versindex].sh_addr;
938 num_versions = sechdrs[versindex].sh_size
939 / sizeof(struct modversion_info);
941 for (i = 0; i < num_versions; i++) {
942 if (strcmp(versions[i].name, symname) != 0)
945 if (versions[i].crc == *crc)
947 printk("%s: disagrees about version of symbol %s\n",
949 DEBUGP("Found checksum %lX vs module %lX\n",
950 *crc, versions[i].crc);
953 /* Not in module's version table. OK, but that taints the kernel. */
954 if (!(tainted & TAINT_FORCED_MODULE)) {
955 printk("%s: no version for \"%s\" found: kernel tainted.\n",
957 add_taint(TAINT_FORCED_MODULE);
962 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
963 unsigned int versindex,
966 const unsigned long *crc;
967 struct module *owner;
969 if (!__find_symbol("struct_module", &owner, &crc, 1))
971 return check_version(sechdrs, versindex, "struct_module", mod,
975 /* First part is kernel version, which we ignore. */
976 static inline int same_magic(const char *amagic, const char *bmagic)
978 amagic += strcspn(amagic, " ");
979 bmagic += strcspn(bmagic, " ");
980 return strcmp(amagic, bmagic) == 0;
983 static inline int check_version(Elf_Shdr *sechdrs,
984 unsigned int versindex,
987 const unsigned long *crc)
992 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
993 unsigned int versindex,
999 static inline int same_magic(const char *amagic, const char *bmagic)
1001 return strcmp(amagic, bmagic) == 0;
1003 #endif /* CONFIG_MODVERSIONS */
1005 /* Resolve a symbol for this module. I.e. if we find one, record usage.
1006 Must be holding module_mutex. */
1007 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
1008 unsigned int versindex,
1012 struct module *owner;
1014 const unsigned long *crc;
1016 ret = __find_symbol(name, &owner, &crc, mod->license_gplok);
1018 /* use_module can fail due to OOM, or module unloading */
1019 if (!check_version(sechdrs, versindex, name, mod, crc) ||
1020 !use_module(mod, owner))
1028 * /sys/module/foo/sections stuff
1029 * J. Corbet <corbet@lwn.net>
1031 #ifdef CONFIG_KALLSYMS
1032 static ssize_t module_sect_show(struct module_attribute *mattr,
1033 struct module *mod, char *buf)
1035 struct module_sect_attr *sattr =
1036 container_of(mattr, struct module_sect_attr, mattr);
1037 return sprintf(buf, "0x%lx\n", sattr->address);
1040 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1041 char *secstrings, Elf_Shdr *sechdrs)
1043 unsigned int nloaded = 0, i, size[2];
1044 struct module_sect_attrs *sect_attrs;
1045 struct module_sect_attr *sattr;
1046 struct attribute **gattr;
1048 /* Count loaded sections and allocate structures */
1049 for (i = 0; i < nsect; i++)
1050 if (sechdrs[i].sh_flags & SHF_ALLOC)
1052 size[0] = ALIGN(sizeof(*sect_attrs)
1053 + nloaded * sizeof(sect_attrs->attrs[0]),
1054 sizeof(sect_attrs->grp.attrs[0]));
1055 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1056 if (! (sect_attrs = kmalloc(size[0] + size[1], GFP_KERNEL)))
1059 /* Setup section attributes. */
1060 sect_attrs->grp.name = "sections";
1061 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1063 sattr = §_attrs->attrs[0];
1064 gattr = §_attrs->grp.attrs[0];
1065 for (i = 0; i < nsect; i++) {
1066 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1068 sattr->address = sechdrs[i].sh_addr;
1069 strlcpy(sattr->name, secstrings + sechdrs[i].sh_name,
1070 MODULE_SECT_NAME_LEN);
1071 sattr->mattr.show = module_sect_show;
1072 sattr->mattr.store = NULL;
1073 sattr->mattr.attr.name = sattr->name;
1074 sattr->mattr.attr.owner = mod;
1075 sattr->mattr.attr.mode = S_IRUGO;
1076 *(gattr++) = &(sattr++)->mattr.attr;
1080 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1083 mod->sect_attrs = sect_attrs;
1089 static void remove_sect_attrs(struct module *mod)
1091 if (mod->sect_attrs) {
1092 sysfs_remove_group(&mod->mkobj.kobj,
1093 &mod->sect_attrs->grp);
1094 /* We are positive that no one is using any sect attrs
1095 * at this point. Deallocate immediately. */
1096 kfree(mod->sect_attrs);
1097 mod->sect_attrs = NULL;
1103 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1104 char *sectstrings, Elf_Shdr *sechdrs)
1108 static inline void remove_sect_attrs(struct module *mod)
1111 #endif /* CONFIG_KALLSYMS */
1113 static int module_add_modinfo_attrs(struct module *mod)
1115 struct module_attribute *attr;
1116 struct module_attribute *temp_attr;
1120 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1121 (ARRAY_SIZE(modinfo_attrs) + 1)),
1123 if (!mod->modinfo_attrs)
1126 temp_attr = mod->modinfo_attrs;
1127 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1129 (attr->test && attr->test(mod))) {
1130 memcpy(temp_attr, attr, sizeof(*temp_attr));
1131 temp_attr->attr.owner = mod;
1132 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1139 static void module_remove_modinfo_attrs(struct module *mod)
1141 struct module_attribute *attr;
1144 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1145 /* pick a field to test for end of list */
1146 if (!attr->attr.name)
1148 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1152 kfree(mod->modinfo_attrs);
1155 static int mod_sysfs_setup(struct module *mod,
1156 struct kernel_param *kparam,
1157 unsigned int num_params)
1161 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1162 err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name);
1165 kobj_set_kset_s(&mod->mkobj, module_subsys);
1166 mod->mkobj.mod = mod;
1167 err = kobject_register(&mod->mkobj.kobj);
1171 err = module_param_sysfs_setup(mod, kparam, num_params);
1175 err = module_add_modinfo_attrs(mod);
1182 kobject_unregister(&mod->mkobj.kobj);
1187 static void mod_kobject_remove(struct module *mod)
1189 module_remove_modinfo_attrs(mod);
1190 module_param_sysfs_remove(mod);
1192 kobject_unregister(&mod->mkobj.kobj);
1196 * unlink the module with the whole machine is stopped with interrupts off
1197 * - this defends against kallsyms not taking locks
1199 static int __unlink_module(void *_mod)
1201 struct module *mod = _mod;
1202 list_del(&mod->list);
1206 /* Free a module, remove from lists, etc (must hold module mutex). */
1207 static void free_module(struct module *mod)
1209 /* Delete from various lists */
1210 stop_machine_run(__unlink_module, mod, NR_CPUS);
1211 remove_sect_attrs(mod);
1212 mod_kobject_remove(mod);
1214 /* Arch-specific cleanup. */
1215 module_arch_cleanup(mod);
1217 /* Module unload stuff */
1218 module_unload_free(mod);
1220 /* This may be NULL, but that's OK */
1221 module_free(mod, mod->module_init);
1224 percpu_modfree(mod->percpu);
1226 /* Finally, free the core (containing the module structure) */
1227 module_free(mod, mod->module_core);
1230 void *__symbol_get(const char *symbol)
1232 struct module *owner;
1233 unsigned long value, flags;
1234 const unsigned long *crc;
1236 spin_lock_irqsave(&modlist_lock, flags);
1237 value = __find_symbol(symbol, &owner, &crc, 1);
1238 if (value && !strong_try_module_get(owner))
1240 spin_unlock_irqrestore(&modlist_lock, flags);
1242 return (void *)value;
1244 EXPORT_SYMBOL_GPL(__symbol_get);
1247 * Ensure that an exported symbol [global namespace] does not already exist
1248 * in the Kernel or in some other modules exported symbol table.
1250 static int verify_export_symbols(struct module *mod)
1252 const char *name = NULL;
1253 unsigned long i, ret = 0;
1254 struct module *owner;
1255 const unsigned long *crc;
1257 for (i = 0; i < mod->num_syms; i++)
1258 if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) {
1259 name = mod->syms[i].name;
1264 for (i = 0; i < mod->num_gpl_syms; i++)
1265 if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) {
1266 name = mod->gpl_syms[i].name;
1273 printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
1274 mod->name, name, module_name(owner));
1279 /* Change all symbols so that sh_value encodes the pointer directly. */
1280 static int simplify_symbols(Elf_Shdr *sechdrs,
1281 unsigned int symindex,
1283 unsigned int versindex,
1284 unsigned int pcpuindex,
1287 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1288 unsigned long secbase;
1289 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1292 for (i = 1; i < n; i++) {
1293 switch (sym[i].st_shndx) {
1295 /* We compiled with -fno-common. These are not
1296 supposed to happen. */
1297 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1298 printk("%s: please compile with -fno-common\n",
1304 /* Don't need to do anything */
1305 DEBUGP("Absolute symbol: 0x%08lx\n",
1306 (long)sym[i].st_value);
1311 = resolve_symbol(sechdrs, versindex,
1312 strtab + sym[i].st_name, mod);
1314 /* Ok if resolved. */
1315 if (sym[i].st_value != 0)
1318 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1321 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1322 mod->name, strtab + sym[i].st_name);
1327 /* Divert to percpu allocation if a percpu var. */
1328 if (sym[i].st_shndx == pcpuindex)
1329 secbase = (unsigned long)mod->percpu;
1331 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1332 sym[i].st_value += secbase;
1340 /* Update size with this section: return offset. */
1341 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
1345 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1346 *size = ret + sechdr->sh_size;
1350 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1351 might -- code, read-only data, read-write data, small data. Tally
1352 sizes, and place the offsets into sh_entsize fields: high bit means it
1354 static void layout_sections(struct module *mod,
1355 const Elf_Ehdr *hdr,
1357 const char *secstrings)
1359 static unsigned long const masks[][2] = {
1360 /* NOTE: all executable code must be the first section
1361 * in this array; otherwise modify the text_size
1362 * finder in the two loops below */
1363 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1364 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1365 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1366 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1370 for (i = 0; i < hdr->e_shnum; i++)
1371 sechdrs[i].sh_entsize = ~0UL;
1373 DEBUGP("Core section allocation order:\n");
1374 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1375 for (i = 0; i < hdr->e_shnum; ++i) {
1376 Elf_Shdr *s = &sechdrs[i];
1378 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1379 || (s->sh_flags & masks[m][1])
1380 || s->sh_entsize != ~0UL
1381 || strncmp(secstrings + s->sh_name,
1384 s->sh_entsize = get_offset(&mod->core_size, s);
1385 DEBUGP("\t%s\n", secstrings + s->sh_name);
1388 mod->core_text_size = mod->core_size;
1391 DEBUGP("Init section allocation order:\n");
1392 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1393 for (i = 0; i < hdr->e_shnum; ++i) {
1394 Elf_Shdr *s = &sechdrs[i];
1396 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1397 || (s->sh_flags & masks[m][1])
1398 || s->sh_entsize != ~0UL
1399 || strncmp(secstrings + s->sh_name,
1402 s->sh_entsize = (get_offset(&mod->init_size, s)
1403 | INIT_OFFSET_MASK);
1404 DEBUGP("\t%s\n", secstrings + s->sh_name);
1407 mod->init_text_size = mod->init_size;
1411 static inline int license_is_gpl_compatible(const char *license)
1413 return (strcmp(license, "GPL") == 0
1414 || strcmp(license, "GPL v2") == 0
1415 || strcmp(license, "GPL and additional rights") == 0
1416 || strcmp(license, "Dual BSD/GPL") == 0
1417 || strcmp(license, "Dual MPL/GPL") == 0);
1420 static void set_license(struct module *mod, const char *license)
1423 license = "unspecified";
1425 mod->license_gplok = license_is_gpl_compatible(license);
1426 if (!mod->license_gplok && !(tainted & TAINT_PROPRIETARY_MODULE)) {
1427 printk(KERN_WARNING "%s: module license '%s' taints kernel.\n",
1428 mod->name, license);
1429 add_taint(TAINT_PROPRIETARY_MODULE);
1433 /* Parse tag=value strings from .modinfo section */
1434 static char *next_string(char *string, unsigned long *secsize)
1436 /* Skip non-zero chars */
1439 if ((*secsize)-- <= 1)
1443 /* Skip any zero padding. */
1444 while (!string[0]) {
1446 if ((*secsize)-- <= 1)
1452 static char *get_modinfo(Elf_Shdr *sechdrs,
1457 unsigned int taglen = strlen(tag);
1458 unsigned long size = sechdrs[info].sh_size;
1460 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1461 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1462 return p + taglen + 1;
1467 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1468 unsigned int infoindex)
1470 struct module_attribute *attr;
1473 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1476 get_modinfo(sechdrs,
1482 #ifdef CONFIG_KALLSYMS
1483 int is_exported(const char *name, const struct module *mod)
1485 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1488 if (lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1495 static char elf_type(const Elf_Sym *sym,
1497 const char *secstrings,
1500 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1501 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1506 if (sym->st_shndx == SHN_UNDEF)
1508 if (sym->st_shndx == SHN_ABS)
1510 if (sym->st_shndx >= SHN_LORESERVE)
1512 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1514 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1515 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1516 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1518 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1523 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1524 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1529 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1530 ".debug", strlen(".debug")) == 0)
1535 static void add_kallsyms(struct module *mod,
1537 unsigned int symindex,
1538 unsigned int strindex,
1539 const char *secstrings)
1543 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1544 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1545 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1547 /* Set types up while we still have access to sections. */
1548 for (i = 0; i < mod->num_symtab; i++)
1549 mod->symtab[i].st_info
1550 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1553 static inline void add_kallsyms(struct module *mod,
1555 unsigned int symindex,
1556 unsigned int strindex,
1557 const char *secstrings)
1560 #endif /* CONFIG_KALLSYMS */
1562 /* Allocate and load the module: note that size of section 0 is always
1563 zero, and we rely on this for optional sections. */
1564 static struct module *load_module(void __user *umod,
1566 const char __user *uargs)
1570 char *secstrings, *args, *modmagic, *strtab = NULL;
1571 unsigned int i, symindex = 0, strindex = 0, setupindex, exindex,
1572 exportindex, modindex, obsparmindex, infoindex, gplindex,
1573 crcindex, gplcrcindex, versindex, pcpuindex, gplfutureindex,
1578 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1579 struct exception_table_entry *extable;
1580 mm_segment_t old_fs;
1582 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1584 if (len < sizeof(*hdr))
1585 return ERR_PTR(-ENOEXEC);
1587 /* Suck in entire file: we'll want most of it. */
1588 /* vmalloc barfs on "unusual" numbers. Check here */
1589 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1590 return ERR_PTR(-ENOMEM);
1591 if (copy_from_user(hdr, umod, len) != 0) {
1596 /* Sanity checks against insmoding binaries or wrong arch,
1597 weird elf version */
1598 if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
1599 || hdr->e_type != ET_REL
1600 || !elf_check_arch(hdr)
1601 || hdr->e_shentsize != sizeof(*sechdrs)) {
1606 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1609 /* Convenience variables */
1610 sechdrs = (void *)hdr + hdr->e_shoff;
1611 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1612 sechdrs[0].sh_addr = 0;
1614 for (i = 1; i < hdr->e_shnum; i++) {
1615 if (sechdrs[i].sh_type != SHT_NOBITS
1616 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1619 /* Mark all sections sh_addr with their address in the
1621 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1623 /* Internal symbols and strings. */
1624 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1626 strindex = sechdrs[i].sh_link;
1627 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1629 #ifndef CONFIG_MODULE_UNLOAD
1630 /* Don't load .exit sections */
1631 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1632 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1636 modindex = find_sec(hdr, sechdrs, secstrings,
1637 ".gnu.linkonce.this_module");
1639 printk(KERN_WARNING "No module found in object\n");
1643 mod = (void *)sechdrs[modindex].sh_addr;
1645 if (symindex == 0) {
1646 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1652 /* Optional sections */
1653 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1654 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1655 gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1656 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1657 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1658 gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1659 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1660 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1661 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1662 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1663 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1664 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1666 /* Don't keep modinfo section */
1667 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1668 #ifdef CONFIG_KALLSYMS
1669 /* Keep symbol and string tables for decoding later. */
1670 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1671 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1674 /* Check module struct version now, before we try to use module. */
1675 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1680 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1681 /* This is allowed: modprobe --force will invalidate it. */
1683 add_taint(TAINT_FORCED_MODULE);
1684 printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
1686 } else if (!same_magic(modmagic, vermagic)) {
1687 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1688 mod->name, modmagic, vermagic);
1693 /* Now copy in args */
1694 arglen = strlen_user(uargs);
1699 args = kmalloc(arglen, GFP_KERNEL);
1704 if (copy_from_user(args, uargs, arglen) != 0) {
1709 /* Userspace could have altered the string after the strlen_user() */
1710 args[arglen - 1] = '\0';
1712 if (find_module(mod->name)) {
1717 mod->state = MODULE_STATE_COMING;
1719 /* Allow arches to frob section contents and sizes. */
1720 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1725 /* We have a special allocation for this section. */
1726 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1727 sechdrs[pcpuindex].sh_addralign,
1733 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1734 mod->percpu = percpu;
1737 /* Determine total sizes, and put offsets in sh_entsize. For now
1738 this is done generically; there doesn't appear to be any
1739 special cases for the architectures. */
1740 layout_sections(mod, hdr, sechdrs, secstrings);
1742 /* Do the allocs. */
1743 ptr = module_alloc(mod->core_size);
1748 memset(ptr, 0, mod->core_size);
1749 mod->module_core = ptr;
1751 ptr = module_alloc(mod->init_size);
1752 if (!ptr && mod->init_size) {
1756 memset(ptr, 0, mod->init_size);
1757 mod->module_init = ptr;
1759 /* Transfer each section which specifies SHF_ALLOC */
1760 DEBUGP("final section addresses:\n");
1761 for (i = 0; i < hdr->e_shnum; i++) {
1764 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1767 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
1768 dest = mod->module_init
1769 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
1771 dest = mod->module_core + sechdrs[i].sh_entsize;
1773 if (sechdrs[i].sh_type != SHT_NOBITS)
1774 memcpy(dest, (void *)sechdrs[i].sh_addr,
1775 sechdrs[i].sh_size);
1776 /* Update sh_addr to point to copy in image. */
1777 sechdrs[i].sh_addr = (unsigned long)dest;
1778 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
1780 /* Module has been moved. */
1781 mod = (void *)sechdrs[modindex].sh_addr;
1783 /* Now we've moved module, initialize linked lists, etc. */
1784 module_unload_init(mod);
1786 /* Set up license info based on the info section */
1787 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
1789 if (strcmp(mod->name, "ndiswrapper") == 0)
1790 add_taint(TAINT_PROPRIETARY_MODULE);
1791 if (strcmp(mod->name, "driverloader") == 0)
1792 add_taint(TAINT_PROPRIETARY_MODULE);
1794 /* Set up MODINFO_ATTR fields */
1795 setup_modinfo(mod, sechdrs, infoindex);
1797 /* Fix up syms, so that st_value is a pointer to location. */
1798 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
1803 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
1804 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
1805 mod->syms = (void *)sechdrs[exportindex].sh_addr;
1807 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
1808 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
1809 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
1811 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
1812 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
1813 sizeof(*mod->gpl_future_syms);
1814 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
1815 if (gplfuturecrcindex)
1816 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
1818 #ifdef CONFIG_MODVERSIONS
1819 if ((mod->num_syms && !crcindex) ||
1820 (mod->num_gpl_syms && !gplcrcindex) ||
1821 (mod->num_gpl_future_syms && !gplfuturecrcindex)) {
1822 printk(KERN_WARNING "%s: No versions for exported symbols."
1823 " Tainting kernel.\n", mod->name);
1824 add_taint(TAINT_FORCED_MODULE);
1828 /* Now do relocations. */
1829 for (i = 1; i < hdr->e_shnum; i++) {
1830 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1831 unsigned int info = sechdrs[i].sh_info;
1833 /* Not a valid relocation section? */
1834 if (info >= hdr->e_shnum)
1837 /* Don't bother with non-allocated sections */
1838 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1841 if (sechdrs[i].sh_type == SHT_REL)
1842 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
1843 else if (sechdrs[i].sh_type == SHT_RELA)
1844 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1850 /* Find duplicate symbols */
1851 err = verify_export_symbols(mod);
1856 /* Set up and sort exception table */
1857 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
1858 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
1859 sort_extable(extable, extable + mod->num_exentries);
1861 /* Finally, copy percpu area over. */
1862 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
1863 sechdrs[pcpuindex].sh_size);
1865 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
1867 err = module_finalize(hdr, sechdrs, mod);
1871 /* flush the icache in correct context */
1876 * Flush the instruction cache, since we've played with text.
1877 * Do it before processing of module parameters, so the module
1878 * can provide parameter accessor functions of its own.
1880 if (mod->module_init)
1881 flush_icache_range((unsigned long)mod->module_init,
1882 (unsigned long)mod->module_init
1884 flush_icache_range((unsigned long)mod->module_core,
1885 (unsigned long)mod->module_core + mod->core_size);
1891 err = obsolete_params(mod->name, mod->args,
1892 (struct obsolete_modparm *)
1893 sechdrs[obsparmindex].sh_addr,
1894 sechdrs[obsparmindex].sh_size
1895 / sizeof(struct obsolete_modparm),
1897 (char *)sechdrs[strindex].sh_addr);
1899 printk(KERN_WARNING "%s: Ignoring new-style "
1900 "parameters in presence of obsolete ones\n",
1903 /* Size of section 0 is 0, so this works well if no params */
1904 err = parse_args(mod->name, mod->args,
1905 (struct kernel_param *)
1906 sechdrs[setupindex].sh_addr,
1907 sechdrs[setupindex].sh_size
1908 / sizeof(struct kernel_param),
1914 err = mod_sysfs_setup(mod,
1915 (struct kernel_param *)
1916 sechdrs[setupindex].sh_addr,
1917 sechdrs[setupindex].sh_size
1918 / sizeof(struct kernel_param));
1921 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
1923 /* Get rid of temporary copy */
1930 module_arch_cleanup(mod);
1932 module_unload_free(mod);
1933 module_free(mod, mod->module_init);
1935 module_free(mod, mod->module_core);
1938 percpu_modfree(percpu);
1943 return ERR_PTR(err);
1946 printk(KERN_ERR "Module len %lu truncated\n", len);
1952 * link the module with the whole machine is stopped with interrupts off
1953 * - this defends against kallsyms not taking locks
1955 static int __link_module(void *_mod)
1957 struct module *mod = _mod;
1958 list_add(&mod->list, &modules);
1962 /* This is where the real work happens */
1964 sys_init_module(void __user *umod,
1966 const char __user *uargs)
1971 /* Must have permission */
1972 if (!capable(CAP_SYS_MODULE))
1975 /* Only one module load at a time, please */
1976 if (mutex_lock_interruptible(&module_mutex) != 0)
1979 /* Do all the hard work */
1980 mod = load_module(umod, len, uargs);
1982 mutex_unlock(&module_mutex);
1983 return PTR_ERR(mod);
1986 /* Now sew it into the lists. They won't access us, since
1987 strong_try_module_get() will fail. */
1988 stop_machine_run(__link_module, mod, NR_CPUS);
1990 /* Drop lock so they can recurse */
1991 mutex_unlock(&module_mutex);
1993 mutex_lock(¬ify_mutex);
1994 notifier_call_chain(&module_notify_list, MODULE_STATE_COMING, mod);
1995 mutex_unlock(¬ify_mutex);
1997 /* Start the module */
1998 if (mod->init != NULL)
2001 /* Init routine failed: abort. Try to protect us from
2002 buggy refcounters. */
2003 mod->state = MODULE_STATE_GOING;
2004 synchronize_sched();
2006 printk(KERN_ERR "%s: module is now stuck!\n",
2010 mutex_lock(&module_mutex);
2012 mutex_unlock(&module_mutex);
2017 /* Now it's a first class citizen! */
2018 mutex_lock(&module_mutex);
2019 mod->state = MODULE_STATE_LIVE;
2020 /* Drop initial reference. */
2022 module_free(mod, mod->module_init);
2023 mod->module_init = NULL;
2025 mod->init_text_size = 0;
2026 mutex_unlock(&module_mutex);
2031 static inline int within(unsigned long addr, void *start, unsigned long size)
2033 return ((void *)addr >= start && (void *)addr < start + size);
2036 #ifdef CONFIG_KALLSYMS
2038 * This ignores the intensely annoying "mapping symbols" found
2039 * in ARM ELF files: $a, $t and $d.
2041 static inline int is_arm_mapping_symbol(const char *str)
2043 return str[0] == '$' && strchr("atd", str[1])
2044 && (str[2] == '\0' || str[2] == '.');
2047 static const char *get_ksymbol(struct module *mod,
2049 unsigned long *size,
2050 unsigned long *offset)
2052 unsigned int i, best = 0;
2053 unsigned long nextval;
2055 /* At worse, next value is at end of module */
2056 if (within(addr, mod->module_init, mod->init_size))
2057 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2059 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2061 /* Scan for closest preceeding symbol, and next symbol. (ELF
2062 starts real symbols at 1). */
2063 for (i = 1; i < mod->num_symtab; i++) {
2064 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2067 /* We ignore unnamed symbols: they're uninformative
2068 * and inserted at a whim. */
2069 if (mod->symtab[i].st_value <= addr
2070 && mod->symtab[i].st_value > mod->symtab[best].st_value
2071 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2072 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2074 if (mod->symtab[i].st_value > addr
2075 && mod->symtab[i].st_value < nextval
2076 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2077 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2078 nextval = mod->symtab[i].st_value;
2084 *size = nextval - mod->symtab[best].st_value;
2085 *offset = addr - mod->symtab[best].st_value;
2086 return mod->strtab + mod->symtab[best].st_name;
2089 /* For kallsyms to ask for address resolution. NULL means not found.
2090 We don't lock, as this is used for oops resolution and races are a
2092 const char *module_address_lookup(unsigned long addr,
2093 unsigned long *size,
2094 unsigned long *offset,
2099 list_for_each_entry(mod, &modules, list) {
2100 if (within(addr, mod->module_init, mod->init_size)
2101 || within(addr, mod->module_core, mod->core_size)) {
2102 *modname = mod->name;
2103 return get_ksymbol(mod, addr, size, offset);
2109 struct module *module_get_kallsym(unsigned int symnum,
2110 unsigned long *value,
2116 mutex_lock(&module_mutex);
2117 list_for_each_entry(mod, &modules, list) {
2118 if (symnum < mod->num_symtab) {
2119 *value = mod->symtab[symnum].st_value;
2120 *type = mod->symtab[symnum].st_info;
2122 mod->strtab + mod->symtab[symnum].st_name,
2124 mutex_unlock(&module_mutex);
2127 symnum -= mod->num_symtab;
2129 mutex_unlock(&module_mutex);
2133 static unsigned long mod_find_symname(struct module *mod, const char *name)
2137 for (i = 0; i < mod->num_symtab; i++)
2138 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2139 mod->symtab[i].st_info != 'U')
2140 return mod->symtab[i].st_value;
2144 /* Look for this name: can be of form module:name. */
2145 unsigned long module_kallsyms_lookup_name(const char *name)
2149 unsigned long ret = 0;
2151 /* Don't lock: we're in enough trouble already. */
2152 if ((colon = strchr(name, ':')) != NULL) {
2154 if ((mod = find_module(name)) != NULL)
2155 ret = mod_find_symname(mod, colon+1);
2158 list_for_each_entry(mod, &modules, list)
2159 if ((ret = mod_find_symname(mod, name)) != 0)
2164 #endif /* CONFIG_KALLSYMS */
2166 /* Called by the /proc file system to return a list of modules. */
2167 static void *m_start(struct seq_file *m, loff_t *pos)
2169 struct list_head *i;
2172 mutex_lock(&module_mutex);
2173 list_for_each(i, &modules) {
2182 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2184 struct list_head *i = p;
2186 if (i->next == &modules)
2191 static void m_stop(struct seq_file *m, void *p)
2193 mutex_unlock(&module_mutex);
2196 static int m_show(struct seq_file *m, void *p)
2198 struct module *mod = list_entry(p, struct module, list);
2199 seq_printf(m, "%s %lu",
2200 mod->name, mod->init_size + mod->core_size);
2201 print_unload_info(m, mod);
2203 /* Informative for users. */
2204 seq_printf(m, " %s",
2205 mod->state == MODULE_STATE_GOING ? "Unloading":
2206 mod->state == MODULE_STATE_COMING ? "Loading":
2208 /* Used by oprofile and other similar tools. */
2209 seq_printf(m, " 0x%p", mod->module_core);
2211 seq_printf(m, "\n");
2215 /* Format: modulename size refcount deps address
2217 Where refcount is a number or -, and deps is a comma-separated list
2220 struct seq_operations modules_op = {
2227 /* Given an address, look for it in the module exception tables. */
2228 const struct exception_table_entry *search_module_extables(unsigned long addr)
2230 unsigned long flags;
2231 const struct exception_table_entry *e = NULL;
2234 spin_lock_irqsave(&modlist_lock, flags);
2235 list_for_each_entry(mod, &modules, list) {
2236 if (mod->num_exentries == 0)
2239 e = search_extable(mod->extable,
2240 mod->extable + mod->num_exentries - 1,
2245 spin_unlock_irqrestore(&modlist_lock, flags);
2247 /* Now, if we found one, we are running inside it now, hence
2248 we cannot unload the module, hence no refcnt needed. */
2252 /* Is this a valid kernel address? We don't grab the lock: we are oopsing. */
2253 struct module *__module_text_address(unsigned long addr)
2257 list_for_each_entry(mod, &modules, list)
2258 if (within(addr, mod->module_init, mod->init_text_size)
2259 || within(addr, mod->module_core, mod->core_text_size))
2264 struct module *module_text_address(unsigned long addr)
2267 unsigned long flags;
2269 spin_lock_irqsave(&modlist_lock, flags);
2270 mod = __module_text_address(addr);
2271 spin_unlock_irqrestore(&modlist_lock, flags);
2276 /* Don't grab lock, we're oopsing. */
2277 void print_modules(void)
2281 printk("Modules linked in:");
2282 list_for_each_entry(mod, &modules, list)
2283 printk(" %s", mod->name);
2287 void module_add_driver(struct module *mod, struct device_driver *drv)
2292 /* Don't check return code; this call is idempotent */
2293 sysfs_create_link(&drv->kobj, &mod->mkobj.kobj, "module");
2295 EXPORT_SYMBOL(module_add_driver);
2297 void module_remove_driver(struct device_driver *drv)
2301 sysfs_remove_link(&drv->kobj, "module");
2303 EXPORT_SYMBOL(module_remove_driver);
2305 #ifdef CONFIG_MODVERSIONS
2306 /* Generate the signature for struct module here, too, for modversions. */
2307 void struct_module(struct module *mod) { return; }
2308 EXPORT_SYMBOL(struct_module);