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[linux-2.6.9-moxart.git] / kernel / module.c
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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/slab.h>
24 #include <linux/vmalloc.h>
25 #include <linux/elf.h>
26 #include <linux/seq_file.h>
27 #include <linux/syscalls.h>
28 #include <linux/fcntl.h>
29 #include <linux/rcupdate.h>
30 #include <linux/cpu.h>
31 #include <linux/moduleparam.h>
32 #include <linux/errno.h>
33 #include <linux/err.h>
34 #include <linux/vermagic.h>
35 #include <linux/notifier.h>
36 #include <linux/stop_machine.h>
37 #include <asm/uaccess.h>
38 #include <asm/semaphore.h>
39 #include <asm/cacheflush.h>
41 #if 0
42 #define DEBUGP printk
43 #else
44 #define DEBUGP(fmt , a...)
45 #endif
47 #ifndef ARCH_SHF_SMALL
48 #define ARCH_SHF_SMALL 0
49 #endif
51 /* If this is set, the section belongs in the init part of the module */
52 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
54 /* Protects module list */
55 static spinlock_t modlist_lock = SPIN_LOCK_UNLOCKED;
57 /* List of modules, protected by module_mutex AND modlist_lock */
58 static DECLARE_MUTEX(module_mutex);
59 static LIST_HEAD(modules);
61 static DECLARE_MUTEX(notify_mutex);
62 static struct notifier_block * module_notify_list;
64 int register_module_notifier(struct notifier_block * nb)
66 int err;
67 down(&notify_mutex);
68 err = notifier_chain_register(&module_notify_list, nb);
69 up(&notify_mutex);
70 return err;
72 EXPORT_SYMBOL(register_module_notifier);
74 int unregister_module_notifier(struct notifier_block * nb)
76 int err;
77 down(&notify_mutex);
78 err = notifier_chain_unregister(&module_notify_list, nb);
79 up(&notify_mutex);
80 return err;
82 EXPORT_SYMBOL(unregister_module_notifier);
84 /* We require a truly strong try_module_get() */
85 static inline int strong_try_module_get(struct module *mod)
87 if (mod && mod->state == MODULE_STATE_COMING)
88 return 0;
89 return try_module_get(mod);
92 /* A thread that wants to hold a reference to a module only while it
93 * is running can call ths to safely exit.
94 * nfsd and lockd use this.
96 void __module_put_and_exit(struct module *mod, long code)
98 module_put(mod);
99 do_exit(code);
101 EXPORT_SYMBOL(__module_put_and_exit);
103 /* Find a module section: 0 means not found. */
104 static unsigned int find_sec(Elf_Ehdr *hdr,
105 Elf_Shdr *sechdrs,
106 const char *secstrings,
107 const char *name)
109 unsigned int i;
111 for (i = 1; i < hdr->e_shnum; i++)
112 /* Alloc bit cleared means "ignore it." */
113 if ((sechdrs[i].sh_flags & SHF_ALLOC)
114 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
115 return i;
116 return 0;
119 /* Provided by the linker */
120 extern const struct kernel_symbol __start___ksymtab[];
121 extern const struct kernel_symbol __stop___ksymtab[];
122 extern const struct kernel_symbol __start___ksymtab_gpl[];
123 extern const struct kernel_symbol __stop___ksymtab_gpl[];
124 extern const unsigned long __start___kcrctab[];
125 extern const unsigned long __start___kcrctab_gpl[];
127 #ifndef CONFIG_MODVERSIONS
128 #define symversion(base, idx) NULL
129 #else
130 #define symversion(base, idx) ((base) ? ((base) + (idx)) : NULL)
131 #endif
133 /* Find a symbol, return value, crc and module which owns it */
134 static unsigned long __find_symbol(const char *name,
135 struct module **owner,
136 const unsigned long **crc,
137 int gplok)
139 struct module *mod;
140 unsigned int i;
142 /* Core kernel first. */
143 *owner = NULL;
144 for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++) {
145 if (strcmp(__start___ksymtab[i].name, name) == 0) {
146 *crc = symversion(__start___kcrctab, i);
147 return __start___ksymtab[i].value;
150 if (gplok) {
151 for (i = 0; __start___ksymtab_gpl+i<__stop___ksymtab_gpl; i++)
152 if (strcmp(__start___ksymtab_gpl[i].name, name) == 0) {
153 *crc = symversion(__start___kcrctab_gpl, i);
154 return __start___ksymtab_gpl[i].value;
158 /* Now try modules. */
159 list_for_each_entry(mod, &modules, list) {
160 *owner = mod;
161 for (i = 0; i < mod->num_syms; i++)
162 if (strcmp(mod->syms[i].name, name) == 0) {
163 *crc = symversion(mod->crcs, i);
164 return mod->syms[i].value;
167 if (gplok) {
168 for (i = 0; i < mod->num_gpl_syms; i++) {
169 if (strcmp(mod->gpl_syms[i].name, name) == 0) {
170 *crc = symversion(mod->gpl_crcs, i);
171 return mod->gpl_syms[i].value;
176 DEBUGP("Failed to find symbol %s\n", name);
177 return 0;
180 /* Find a symbol in this elf symbol table */
181 static unsigned long find_local_symbol(Elf_Shdr *sechdrs,
182 unsigned int symindex,
183 const char *strtab,
184 const char *name)
186 unsigned int i;
187 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
189 /* Search (defined) internal symbols first. */
190 for (i = 1; i < sechdrs[symindex].sh_size/sizeof(*sym); i++) {
191 if (sym[i].st_shndx != SHN_UNDEF
192 && strcmp(name, strtab + sym[i].st_name) == 0)
193 return sym[i].st_value;
195 return 0;
198 /* Search for module by name: must hold module_mutex. */
199 static struct module *find_module(const char *name)
201 struct module *mod;
203 list_for_each_entry(mod, &modules, list) {
204 if (strcmp(mod->name, name) == 0)
205 return mod;
207 return NULL;
210 #ifdef CONFIG_SMP
211 /* Number of blocks used and allocated. */
212 static unsigned int pcpu_num_used, pcpu_num_allocated;
213 /* Size of each block. -ve means used. */
214 static int *pcpu_size;
216 static int split_block(unsigned int i, unsigned short size)
218 /* Reallocation required? */
219 if (pcpu_num_used + 1 > pcpu_num_allocated) {
220 int *new = kmalloc(sizeof(new[0]) * pcpu_num_allocated*2,
221 GFP_KERNEL);
222 if (!new)
223 return 0;
225 memcpy(new, pcpu_size, sizeof(new[0])*pcpu_num_allocated);
226 pcpu_num_allocated *= 2;
227 kfree(pcpu_size);
228 pcpu_size = new;
231 /* Insert a new subblock */
232 memmove(&pcpu_size[i+1], &pcpu_size[i],
233 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
234 pcpu_num_used++;
236 pcpu_size[i+1] -= size;
237 pcpu_size[i] = size;
238 return 1;
241 static inline unsigned int block_size(int val)
243 if (val < 0)
244 return -val;
245 return val;
248 /* Created by linker magic */
249 extern char __per_cpu_start[], __per_cpu_end[];
251 static void *percpu_modalloc(unsigned long size, unsigned long align)
253 unsigned long extra;
254 unsigned int i;
255 void *ptr;
257 BUG_ON(align > SMP_CACHE_BYTES);
259 ptr = __per_cpu_start;
260 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
261 /* Extra for alignment requirement. */
262 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
263 BUG_ON(i == 0 && extra != 0);
265 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
266 continue;
268 /* Transfer extra to previous block. */
269 if (pcpu_size[i-1] < 0)
270 pcpu_size[i-1] -= extra;
271 else
272 pcpu_size[i-1] += extra;
273 pcpu_size[i] -= extra;
274 ptr += extra;
276 /* Split block if warranted */
277 if (pcpu_size[i] - size > sizeof(unsigned long))
278 if (!split_block(i, size))
279 return NULL;
281 /* Mark allocated */
282 pcpu_size[i] = -pcpu_size[i];
283 return ptr;
286 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
287 size);
288 return NULL;
291 static void percpu_modfree(void *freeme)
293 unsigned int i;
294 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
296 /* First entry is core kernel percpu data. */
297 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
298 if (ptr == freeme) {
299 pcpu_size[i] = -pcpu_size[i];
300 goto free;
303 BUG();
305 free:
306 /* Merge with previous? */
307 if (pcpu_size[i-1] >= 0) {
308 pcpu_size[i-1] += pcpu_size[i];
309 pcpu_num_used--;
310 memmove(&pcpu_size[i], &pcpu_size[i+1],
311 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
312 i--;
314 /* Merge with next? */
315 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
316 pcpu_size[i] += pcpu_size[i+1];
317 pcpu_num_used--;
318 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
319 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
323 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
324 Elf_Shdr *sechdrs,
325 const char *secstrings)
327 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
330 static int percpu_modinit(void)
332 pcpu_num_used = 2;
333 pcpu_num_allocated = 2;
334 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
335 GFP_KERNEL);
336 /* Static in-kernel percpu data (used). */
337 pcpu_size[0] = -ALIGN(__per_cpu_end-__per_cpu_start, SMP_CACHE_BYTES);
338 /* Free room. */
339 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
340 if (pcpu_size[1] < 0) {
341 printk(KERN_ERR "No per-cpu room for modules.\n");
342 pcpu_num_used = 1;
345 return 0;
347 __initcall(percpu_modinit);
348 #else /* ... !CONFIG_SMP */
349 static inline void *percpu_modalloc(unsigned long size, unsigned long align)
351 return NULL;
353 static inline void percpu_modfree(void *pcpuptr)
355 BUG();
357 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
358 Elf_Shdr *sechdrs,
359 const char *secstrings)
361 return 0;
363 static inline void percpu_modcopy(void *pcpudst, const void *src,
364 unsigned long size)
366 /* pcpusec should be 0, and size of that section should be 0. */
367 BUG_ON(size != 0);
369 #endif /* CONFIG_SMP */
371 static int add_attribute(struct module *mod, struct kernel_param *kp)
373 struct module_attribute *a;
374 int retval;
376 a = &mod->mkobj->attr[mod->mkobj->num_attributes];
377 a->attr.name = (char *)kp->name;
378 a->attr.owner = mod;
379 a->attr.mode = kp->perm;
380 a->param = kp;
381 retval = sysfs_create_file(&mod->mkobj->kobj, &a->attr);
382 if (!retval)
383 mod->mkobj->num_attributes++;
384 return retval;
387 #ifdef CONFIG_MODULE_UNLOAD
388 /* Init the unload section of the module. */
389 static void module_unload_init(struct module *mod)
391 unsigned int i;
393 INIT_LIST_HEAD(&mod->modules_which_use_me);
394 for (i = 0; i < NR_CPUS; i++)
395 local_set(&mod->ref[i].count, 0);
396 /* Hold reference count during initialization. */
397 local_set(&mod->ref[smp_processor_id()].count, 1);
398 /* Backwards compatibility macros put refcount during init. */
399 mod->waiter = current;
402 /* modules using other modules */
403 struct module_use
405 struct list_head list;
406 struct module *module_which_uses;
409 /* Does a already use b? */
410 static int already_uses(struct module *a, struct module *b)
412 struct module_use *use;
414 list_for_each_entry(use, &b->modules_which_use_me, list) {
415 if (use->module_which_uses == a) {
416 DEBUGP("%s uses %s!\n", a->name, b->name);
417 return 1;
420 DEBUGP("%s does not use %s!\n", a->name, b->name);
421 return 0;
424 /* Module a uses b */
425 static int use_module(struct module *a, struct module *b)
427 struct module_use *use;
428 if (b == NULL || already_uses(a, b)) return 1;
430 if (!strong_try_module_get(b))
431 return 0;
433 DEBUGP("Allocating new usage for %s.\n", a->name);
434 use = kmalloc(sizeof(*use), GFP_ATOMIC);
435 if (!use) {
436 printk("%s: out of memory loading\n", a->name);
437 module_put(b);
438 return 0;
441 use->module_which_uses = a;
442 list_add(&use->list, &b->modules_which_use_me);
443 return 1;
446 /* Clear the unload stuff of the module. */
447 static void module_unload_free(struct module *mod)
449 struct module *i;
451 list_for_each_entry(i, &modules, list) {
452 struct module_use *use;
454 list_for_each_entry(use, &i->modules_which_use_me, list) {
455 if (use->module_which_uses == mod) {
456 DEBUGP("%s unusing %s\n", mod->name, i->name);
457 module_put(i);
458 list_del(&use->list);
459 kfree(use);
460 /* There can be at most one match. */
461 break;
467 #ifdef CONFIG_MODULE_FORCE_UNLOAD
468 static inline int try_force(unsigned int flags)
470 int ret = (flags & O_TRUNC);
471 if (ret)
472 tainted |= TAINT_FORCED_MODULE;
473 return ret;
475 #else
476 static inline int try_force(unsigned int flags)
478 return 0;
480 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
482 struct stopref
484 struct module *mod;
485 int flags;
486 int *forced;
489 /* Whole machine is stopped with interrupts off when this runs. */
490 static inline int __try_stop_module(void *_sref)
492 struct stopref *sref = _sref;
494 /* If it's not unused, quit unless we are told to block. */
495 if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
496 if (!(*sref->forced = try_force(sref->flags)))
497 return -EWOULDBLOCK;
500 /* Mark it as dying. */
501 sref->mod->state = MODULE_STATE_GOING;
502 return 0;
505 static int try_stop_module(struct module *mod, int flags, int *forced)
507 struct stopref sref = { mod, flags, forced };
509 return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
512 unsigned int module_refcount(struct module *mod)
514 unsigned int i, total = 0;
516 for (i = 0; i < NR_CPUS; i++)
517 total += local_read(&mod->ref[i].count);
518 return total;
520 EXPORT_SYMBOL(module_refcount);
522 /* This exists whether we can unload or not */
523 static void free_module(struct module *mod);
525 static void wait_for_zero_refcount(struct module *mod)
527 /* Since we might sleep for some time, drop the semaphore first */
528 up(&module_mutex);
529 for (;;) {
530 DEBUGP("Looking at refcount...\n");
531 set_current_state(TASK_UNINTERRUPTIBLE);
532 if (module_refcount(mod) == 0)
533 break;
534 schedule();
536 current->state = TASK_RUNNING;
537 down(&module_mutex);
540 asmlinkage long
541 sys_delete_module(const char __user *name_user, unsigned int flags)
543 struct module *mod;
544 char name[MODULE_NAME_LEN];
545 int ret, forced = 0;
547 if (!capable(CAP_SYS_MODULE))
548 return -EPERM;
550 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
551 return -EFAULT;
552 name[MODULE_NAME_LEN-1] = '\0';
554 if (down_interruptible(&module_mutex) != 0)
555 return -EINTR;
557 mod = find_module(name);
558 if (!mod) {
559 ret = -ENOENT;
560 goto out;
563 if (!list_empty(&mod->modules_which_use_me)) {
564 /* Other modules depend on us: get rid of them first. */
565 ret = -EWOULDBLOCK;
566 goto out;
569 /* Doing init or already dying? */
570 if (mod->state != MODULE_STATE_LIVE) {
571 /* FIXME: if (force), slam module count and wake up
572 waiter --RR */
573 DEBUGP("%s already dying\n", mod->name);
574 ret = -EBUSY;
575 goto out;
578 /* If it has an init func, it must have an exit func to unload */
579 if ((mod->init != NULL && mod->exit == NULL)
580 || mod->unsafe) {
581 forced = try_force(flags);
582 if (!forced) {
583 /* This module can't be removed */
584 ret = -EBUSY;
585 goto out;
589 /* Set this up before setting mod->state */
590 mod->waiter = current;
592 /* Stop the machine so refcounts can't move and disable module. */
593 ret = try_stop_module(mod, flags, &forced);
595 /* Never wait if forced. */
596 if (!forced && module_refcount(mod) != 0)
597 wait_for_zero_refcount(mod);
599 /* Final destruction now noone is using it. */
600 if (mod->exit != NULL) {
601 up(&module_mutex);
602 mod->exit();
603 down(&module_mutex);
605 free_module(mod);
607 out:
608 up(&module_mutex);
609 return ret;
612 static void print_unload_info(struct seq_file *m, struct module *mod)
614 struct module_use *use;
615 int printed_something = 0;
617 seq_printf(m, " %u ", module_refcount(mod));
619 /* Always include a trailing , so userspace can differentiate
620 between this and the old multi-field proc format. */
621 list_for_each_entry(use, &mod->modules_which_use_me, list) {
622 printed_something = 1;
623 seq_printf(m, "%s,", use->module_which_uses->name);
626 if (mod->unsafe) {
627 printed_something = 1;
628 seq_printf(m, "[unsafe],");
631 if (mod->init != NULL && mod->exit == NULL) {
632 printed_something = 1;
633 seq_printf(m, "[permanent],");
636 if (!printed_something)
637 seq_printf(m, "-");
640 void __symbol_put(const char *symbol)
642 struct module *owner;
643 unsigned long flags;
644 const unsigned long *crc;
646 spin_lock_irqsave(&modlist_lock, flags);
647 if (!__find_symbol(symbol, &owner, &crc, 1))
648 BUG();
649 module_put(owner);
650 spin_unlock_irqrestore(&modlist_lock, flags);
652 EXPORT_SYMBOL(__symbol_put);
654 void symbol_put_addr(void *addr)
656 unsigned long flags;
658 spin_lock_irqsave(&modlist_lock, flags);
659 if (!kernel_text_address((unsigned long)addr))
660 BUG();
662 module_put(module_text_address((unsigned long)addr));
663 spin_unlock_irqrestore(&modlist_lock, flags);
665 EXPORT_SYMBOL_GPL(symbol_put_addr);
667 static int refcnt_get_fn(char *buffer, struct kernel_param *kp)
669 struct module *mod = container_of(kp, struct module, refcnt_param);
671 /* sysfs holds one reference. */
672 return sprintf(buffer, "%u", module_refcount(mod)-1);
675 static inline int sysfs_unload_setup(struct module *mod)
677 mod->refcnt_param.name = "refcnt";
678 mod->refcnt_param.perm = 0444;
679 mod->refcnt_param.get = refcnt_get_fn;
681 return add_attribute(mod, &mod->refcnt_param);
684 #else /* !CONFIG_MODULE_UNLOAD */
685 static void print_unload_info(struct seq_file *m, struct module *mod)
687 /* We don't know the usage count, or what modules are using. */
688 seq_printf(m, " - -");
691 static inline void module_unload_free(struct module *mod)
695 static inline int use_module(struct module *a, struct module *b)
697 return strong_try_module_get(b);
700 static inline void module_unload_init(struct module *mod)
704 asmlinkage long
705 sys_delete_module(const char __user *name_user, unsigned int flags)
707 return -ENOSYS;
710 static inline int sysfs_unload_setup(struct module *mod)
712 return 0;
714 #endif /* CONFIG_MODULE_UNLOAD */
716 #ifdef CONFIG_OBSOLETE_MODPARM
717 /* Bounds checking done below */
718 static int obsparm_copy_string(const char *val, struct kernel_param *kp)
720 strcpy(kp->arg, val);
721 return 0;
724 int set_obsolete(const char *val, struct kernel_param *kp)
726 unsigned int min, max;
727 unsigned int size, maxsize;
728 int dummy;
729 char *endp;
730 const char *p;
731 struct obsolete_modparm *obsparm = kp->arg;
733 if (!val) {
734 printk(KERN_ERR "Parameter %s needs an argument\n", kp->name);
735 return -EINVAL;
738 /* type is: [min[-max]]{b,h,i,l,s} */
739 p = obsparm->type;
740 min = simple_strtol(p, &endp, 10);
741 if (endp == obsparm->type)
742 min = max = 1;
743 else if (*endp == '-') {
744 p = endp+1;
745 max = simple_strtol(p, &endp, 10);
746 } else
747 max = min;
748 switch (*endp) {
749 case 'b':
750 return param_array(kp->name, val, min, max, obsparm->addr,
751 1, param_set_byte, &dummy);
752 case 'h':
753 return param_array(kp->name, val, min, max, obsparm->addr,
754 sizeof(short), param_set_short, &dummy);
755 case 'i':
756 return param_array(kp->name, val, min, max, obsparm->addr,
757 sizeof(int), param_set_int, &dummy);
758 case 'l':
759 return param_array(kp->name, val, min, max, obsparm->addr,
760 sizeof(long), param_set_long, &dummy);
761 case 's':
762 return param_array(kp->name, val, min, max, obsparm->addr,
763 sizeof(char *), param_set_charp, &dummy);
765 case 'c':
766 /* Undocumented: 1-5c50 means 1-5 strings of up to 49 chars,
767 and the decl is "char xxx[5][50];" */
768 p = endp+1;
769 maxsize = simple_strtol(p, &endp, 10);
770 /* We check lengths here (yes, this is a hack). */
771 p = val;
772 while (p[size = strcspn(p, ",")]) {
773 if (size >= maxsize)
774 goto oversize;
775 p += size+1;
777 if (size >= maxsize)
778 goto oversize;
779 return param_array(kp->name, val, min, max, obsparm->addr,
780 maxsize, obsparm_copy_string, &dummy);
782 printk(KERN_ERR "Unknown obsolete parameter type %s\n", obsparm->type);
783 return -EINVAL;
784 oversize:
785 printk(KERN_ERR
786 "Parameter %s doesn't fit in %u chars.\n", kp->name, maxsize);
787 return -EINVAL;
790 static int obsolete_params(const char *name,
791 char *args,
792 struct obsolete_modparm obsparm[],
793 unsigned int num,
794 Elf_Shdr *sechdrs,
795 unsigned int symindex,
796 const char *strtab)
798 struct kernel_param *kp;
799 unsigned int i;
800 int ret;
802 kp = kmalloc(sizeof(kp[0]) * num, GFP_KERNEL);
803 if (!kp)
804 return -ENOMEM;
806 for (i = 0; i < num; i++) {
807 char sym_name[128 + sizeof(MODULE_SYMBOL_PREFIX)];
809 snprintf(sym_name, sizeof(sym_name), "%s%s",
810 MODULE_SYMBOL_PREFIX, obsparm[i].name);
812 kp[i].name = obsparm[i].name;
813 kp[i].perm = 000;
814 kp[i].set = set_obsolete;
815 kp[i].get = NULL;
816 obsparm[i].addr
817 = (void *)find_local_symbol(sechdrs, symindex, strtab,
818 sym_name);
819 if (!obsparm[i].addr) {
820 printk("%s: falsely claims to have parameter %s\n",
821 name, obsparm[i].name);
822 ret = -EINVAL;
823 goto out;
825 kp[i].arg = &obsparm[i];
828 ret = parse_args(name, args, kp, num, NULL);
829 out:
830 kfree(kp);
831 return ret;
833 #else
834 static int obsolete_params(const char *name,
835 char *args,
836 struct obsolete_modparm obsparm[],
837 unsigned int num,
838 Elf_Shdr *sechdrs,
839 unsigned int symindex,
840 const char *strtab)
842 if (num != 0)
843 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
844 name);
845 return 0;
847 #endif /* CONFIG_OBSOLETE_MODPARM */
849 static const char vermagic[] = VERMAGIC_STRING;
851 #ifdef CONFIG_MODVERSIONS
852 static int check_version(Elf_Shdr *sechdrs,
853 unsigned int versindex,
854 const char *symname,
855 struct module *mod,
856 const unsigned long *crc)
858 unsigned int i, num_versions;
859 struct modversion_info *versions;
861 /* Exporting module didn't supply crcs? OK, we're already tainted. */
862 if (!crc)
863 return 1;
865 versions = (void *) sechdrs[versindex].sh_addr;
866 num_versions = sechdrs[versindex].sh_size
867 / sizeof(struct modversion_info);
869 for (i = 0; i < num_versions; i++) {
870 if (strcmp(versions[i].name, symname) != 0)
871 continue;
873 if (versions[i].crc == *crc)
874 return 1;
875 printk("%s: disagrees about version of symbol %s\n",
876 mod->name, symname);
877 DEBUGP("Found checksum %lX vs module %lX\n",
878 *crc, versions[i].crc);
879 return 0;
881 /* Not in module's version table. OK, but that taints the kernel. */
882 if (!(tainted & TAINT_FORCED_MODULE)) {
883 printk("%s: no version for \"%s\" found: kernel tainted.\n",
884 mod->name, symname);
885 tainted |= TAINT_FORCED_MODULE;
887 return 1;
890 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
891 unsigned int versindex,
892 struct module *mod)
894 const unsigned long *crc;
895 struct module *owner;
897 if (!__find_symbol("struct_module", &owner, &crc, 1))
898 BUG();
899 return check_version(sechdrs, versindex, "struct_module", mod,
900 crc);
903 /* First part is kernel version, which we ignore. */
904 static inline int same_magic(const char *amagic, const char *bmagic)
906 amagic += strcspn(amagic, " ");
907 bmagic += strcspn(bmagic, " ");
908 return strcmp(amagic, bmagic) == 0;
910 #else
911 static inline int check_version(Elf_Shdr *sechdrs,
912 unsigned int versindex,
913 const char *symname,
914 struct module *mod,
915 const unsigned long *crc)
917 return 1;
920 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
921 unsigned int versindex,
922 struct module *mod)
924 return 1;
927 static inline int same_magic(const char *amagic, const char *bmagic)
929 return strcmp(amagic, bmagic) == 0;
931 #endif /* CONFIG_MODVERSIONS */
933 /* Resolve a symbol for this module. I.e. if we find one, record usage.
934 Must be holding module_mutex. */
935 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
936 unsigned int versindex,
937 const char *name,
938 struct module *mod)
940 struct module *owner;
941 unsigned long ret;
942 const unsigned long *crc;
944 spin_lock_irq(&modlist_lock);
945 ret = __find_symbol(name, &owner, &crc, mod->license_gplok);
946 if (ret) {
947 /* use_module can fail due to OOM, or module unloading */
948 if (!check_version(sechdrs, versindex, name, mod, crc) ||
949 !use_module(mod, owner))
950 ret = 0;
952 spin_unlock_irq(&modlist_lock);
953 return ret;
958 * /sys/module/foo/sections stuff
959 * J. Corbet <corbet@lwn.net>
961 #ifdef CONFIG_KALLSYMS
962 static void module_sect_attrs_release(struct kobject *kobj)
964 kfree(container_of(kobj, struct module_sections, kobj));
967 static ssize_t module_sect_show(struct kobject *kobj, struct attribute *attr,
968 char *buf)
970 struct module_sect_attr *sattr =
971 container_of(attr, struct module_sect_attr, attr);
972 return sprintf(buf, "0x%lx\n", sattr->address);
975 static struct sysfs_ops module_sect_ops = {
976 .show = module_sect_show,
979 static struct kobj_type module_sect_ktype = {
980 .sysfs_ops = &module_sect_ops,
981 .release = module_sect_attrs_release,
984 static void add_sect_attrs(struct module *mod, unsigned int nsect,
985 char *secstrings, Elf_Shdr *sechdrs)
987 unsigned int nloaded = 0, i;
988 struct module_sect_attr *sattr;
990 if (!mod->mkobj)
991 return;
993 /* Count loaded sections and allocate structures */
994 for (i = 0; i < nsect; i++)
995 if (sechdrs[i].sh_flags & SHF_ALLOC)
996 nloaded++;
997 mod->sect_attrs = kmalloc(sizeof(struct module_sections) +
998 nloaded*sizeof(mod->sect_attrs->attrs[0]), GFP_KERNEL);
999 if (! mod->sect_attrs)
1000 return;
1002 /* sections entry setup */
1003 memset(mod->sect_attrs, 0, sizeof(struct module_sections));
1004 if (kobject_set_name(&mod->sect_attrs->kobj, "sections"))
1005 goto out;
1006 mod->sect_attrs->kobj.parent = &mod->mkobj->kobj;
1007 mod->sect_attrs->kobj.ktype = &module_sect_ktype;
1008 if (kobject_register(&mod->sect_attrs->kobj))
1009 goto out;
1011 /* And the section attributes. */
1012 sattr = &mod->sect_attrs->attrs[0];
1013 for (i = 0; i < nsect; i++) {
1014 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1015 continue;
1016 sattr->address = sechdrs[i].sh_addr;
1017 strlcpy(sattr->name, secstrings + sechdrs[i].sh_name,
1018 MODULE_SECT_NAME_LEN);
1019 sattr->attr.name = sattr->name;
1020 sattr->attr.owner = mod;
1021 sattr->attr.mode = S_IRUGO;
1022 (void) sysfs_create_file(&mod->sect_attrs->kobj, &sattr->attr);
1023 sattr++;
1025 return;
1026 out:
1027 kfree(mod->sect_attrs);
1028 mod->sect_attrs = NULL;
1031 static void remove_sect_attrs(struct module *mod)
1033 if (mod->sect_attrs) {
1034 kobject_unregister(&mod->sect_attrs->kobj);
1035 mod->sect_attrs = NULL;
1040 #else
1041 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1042 char *sectstrings, Elf_Shdr *sechdrs)
1046 static inline void remove_sect_attrs(struct module *mod)
1049 #endif /* CONFIG_KALLSYMS */
1054 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
1056 static ssize_t module_attr_show(struct kobject *kobj,
1057 struct attribute *attr,
1058 char *buf)
1060 int count;
1061 struct module_attribute *attribute = to_module_attr(attr);
1063 if (!attribute->param->get)
1064 return -EPERM;
1066 count = attribute->param->get(buf, attribute->param);
1067 if (count > 0) {
1068 strcat(buf, "\n");
1069 ++count;
1071 return count;
1074 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
1075 static ssize_t module_attr_store(struct kobject *kobj,
1076 struct attribute *attr,
1077 const char *buf, size_t len)
1079 int err;
1080 struct module_attribute *attribute = to_module_attr(attr);
1082 if (!attribute->param->set)
1083 return -EPERM;
1085 err = attribute->param->set(buf, attribute->param);
1086 if (!err)
1087 return len;
1088 return err;
1091 static struct sysfs_ops module_sysfs_ops = {
1092 .show = module_attr_show,
1093 .store = module_attr_store,
1096 static void module_kobj_release(struct kobject *kobj)
1098 kfree(container_of(kobj, struct module_kobject, kobj));
1101 static struct kobj_type module_ktype = {
1102 .sysfs_ops = &module_sysfs_ops,
1103 .release = &module_kobj_release,
1105 static decl_subsys(module, &module_ktype, NULL);
1107 static int mod_sysfs_setup(struct module *mod,
1108 struct kernel_param *kparam,
1109 unsigned int num_params)
1111 unsigned int i;
1112 int err;
1114 /* We overallocate: not every param is in sysfs, and maybe no refcnt */
1115 mod->mkobj = kmalloc(sizeof(*mod->mkobj)
1116 + sizeof(mod->mkobj->attr[0]) * (num_params+1),
1117 GFP_KERNEL);
1118 if (!mod->mkobj)
1119 return -ENOMEM;
1121 memset(&mod->mkobj->kobj, 0, sizeof(mod->mkobj->kobj));
1122 err = kobject_set_name(&mod->mkobj->kobj, mod->name);
1123 if (err)
1124 goto out;
1125 kobj_set_kset_s(mod->mkobj, module_subsys);
1126 err = kobject_register(&mod->mkobj->kobj);
1127 if (err)
1128 goto out;
1130 mod->mkobj->num_attributes = 0;
1132 for (i = 0; i < num_params; i++) {
1133 if (kparam[i].perm) {
1134 err = add_attribute(mod, &kparam[i]);
1135 if (err)
1136 goto out_unreg;
1139 err = sysfs_unload_setup(mod);
1140 if (err)
1141 goto out_unreg;
1142 return 0;
1144 out_unreg:
1145 for (i = 0; i < mod->mkobj->num_attributes; i++)
1146 sysfs_remove_file(&mod->mkobj->kobj,&mod->mkobj->attr[i].attr);
1147 /* Calls module_kobj_release */
1148 kobject_unregister(&mod->mkobj->kobj);
1149 return err;
1150 out:
1151 kfree(mod->mkobj);
1152 return err;
1155 static void mod_kobject_remove(struct module *mod)
1157 unsigned int i;
1158 for (i = 0; i < mod->mkobj->num_attributes; i++)
1159 sysfs_remove_file(&mod->mkobj->kobj,&mod->mkobj->attr[i].attr);
1160 /* Calls module_kobj_release */
1161 kobject_unregister(&mod->mkobj->kobj);
1164 /* Free a module, remove from lists, etc (must hold module mutex). */
1165 static void free_module(struct module *mod)
1167 /* Delete from various lists */
1168 spin_lock_irq(&modlist_lock);
1169 list_del(&mod->list);
1170 spin_unlock_irq(&modlist_lock);
1172 remove_sect_attrs(mod);
1173 mod_kobject_remove(mod);
1175 /* Arch-specific cleanup. */
1176 module_arch_cleanup(mod);
1178 /* Module unload stuff */
1179 module_unload_free(mod);
1181 /* This may be NULL, but that's OK */
1182 module_free(mod, mod->module_init);
1183 kfree(mod->args);
1184 if (mod->percpu)
1185 percpu_modfree(mod->percpu);
1187 /* Finally, free the core (containing the module structure) */
1188 module_free(mod, mod->module_core);
1191 void *__symbol_get(const char *symbol)
1193 struct module *owner;
1194 unsigned long value, flags;
1195 const unsigned long *crc;
1197 spin_lock_irqsave(&modlist_lock, flags);
1198 value = __find_symbol(symbol, &owner, &crc, 1);
1199 if (value && !strong_try_module_get(owner))
1200 value = 0;
1201 spin_unlock_irqrestore(&modlist_lock, flags);
1203 return (void *)value;
1205 EXPORT_SYMBOL_GPL(__symbol_get);
1207 /* Change all symbols so that sh_value encodes the pointer directly. */
1208 static int simplify_symbols(Elf_Shdr *sechdrs,
1209 unsigned int symindex,
1210 const char *strtab,
1211 unsigned int versindex,
1212 unsigned int pcpuindex,
1213 struct module *mod)
1215 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1216 unsigned long secbase;
1217 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1218 int ret = 0;
1220 for (i = 1; i < n; i++) {
1221 switch (sym[i].st_shndx) {
1222 case SHN_COMMON:
1223 /* We compiled with -fno-common. These are not
1224 supposed to happen. */
1225 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1226 printk("%s: please compile with -fno-common\n",
1227 mod->name);
1228 ret = -ENOEXEC;
1229 break;
1231 case SHN_ABS:
1232 /* Don't need to do anything */
1233 DEBUGP("Absolute symbol: 0x%08lx\n",
1234 (long)sym[i].st_value);
1235 break;
1237 case SHN_UNDEF:
1238 sym[i].st_value
1239 = resolve_symbol(sechdrs, versindex,
1240 strtab + sym[i].st_name, mod);
1242 /* Ok if resolved. */
1243 if (sym[i].st_value != 0)
1244 break;
1245 /* Ok if weak. */
1246 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1247 break;
1249 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1250 mod->name, strtab + sym[i].st_name);
1251 ret = -ENOENT;
1252 break;
1254 default:
1255 /* Divert to percpu allocation if a percpu var. */
1256 if (sym[i].st_shndx == pcpuindex)
1257 secbase = (unsigned long)mod->percpu;
1258 else
1259 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1260 sym[i].st_value += secbase;
1261 break;
1265 return ret;
1268 /* Update size with this section: return offset. */
1269 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
1271 long ret;
1273 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1274 *size = ret + sechdr->sh_size;
1275 return ret;
1278 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1279 might -- code, read-only data, read-write data, small data. Tally
1280 sizes, and place the offsets into sh_entsize fields: high bit means it
1281 belongs in init. */
1282 static void layout_sections(struct module *mod,
1283 const Elf_Ehdr *hdr,
1284 Elf_Shdr *sechdrs,
1285 const char *secstrings)
1287 static unsigned long const masks[][2] = {
1288 /* NOTE: all executable code must be the first section
1289 * in this array; otherwise modify the text_size
1290 * finder in the two loops below */
1291 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1292 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1293 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1294 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1296 unsigned int m, i;
1298 for (i = 0; i < hdr->e_shnum; i++)
1299 sechdrs[i].sh_entsize = ~0UL;
1301 DEBUGP("Core section allocation order:\n");
1302 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1303 for (i = 0; i < hdr->e_shnum; ++i) {
1304 Elf_Shdr *s = &sechdrs[i];
1306 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1307 || (s->sh_flags & masks[m][1])
1308 || s->sh_entsize != ~0UL
1309 || strncmp(secstrings + s->sh_name,
1310 ".init", 5) == 0)
1311 continue;
1312 s->sh_entsize = get_offset(&mod->core_size, s);
1313 DEBUGP("\t%s\n", secstrings + s->sh_name);
1315 if (m == 0)
1316 mod->core_text_size = mod->core_size;
1319 DEBUGP("Init section allocation order:\n");
1320 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1321 for (i = 0; i < hdr->e_shnum; ++i) {
1322 Elf_Shdr *s = &sechdrs[i];
1324 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1325 || (s->sh_flags & masks[m][1])
1326 || s->sh_entsize != ~0UL
1327 || strncmp(secstrings + s->sh_name,
1328 ".init", 5) != 0)
1329 continue;
1330 s->sh_entsize = (get_offset(&mod->init_size, s)
1331 | INIT_OFFSET_MASK);
1332 DEBUGP("\t%s\n", secstrings + s->sh_name);
1334 if (m == 0)
1335 mod->init_text_size = mod->init_size;
1339 static inline int license_is_gpl_compatible(const char *license)
1341 return (strcmp(license, "GPL") == 0
1342 || strcmp(license, "GPL v2") == 0
1343 || strcmp(license, "GPL and additional rights") == 0
1344 || strcmp(license, "Dual BSD/GPL") == 0
1345 || strcmp(license, "Dual MPL/GPL") == 0);
1348 static void set_license(struct module *mod, const char *license)
1350 if (!license)
1351 license = "unspecified";
1353 mod->license_gplok = license_is_gpl_compatible(license);
1354 if (!mod->license_gplok && !(tainted & TAINT_PROPRIETARY_MODULE)) {
1355 printk(KERN_WARNING "%s: module license '%s' taints kernel.\n",
1356 mod->name, license);
1357 tainted |= TAINT_PROPRIETARY_MODULE;
1361 /* Parse tag=value strings from .modinfo section */
1362 static char *next_string(char *string, unsigned long *secsize)
1364 /* Skip non-zero chars */
1365 while (string[0]) {
1366 string++;
1367 if ((*secsize)-- <= 1)
1368 return NULL;
1371 /* Skip any zero padding. */
1372 while (!string[0]) {
1373 string++;
1374 if ((*secsize)-- <= 1)
1375 return NULL;
1377 return string;
1380 static char *get_modinfo(Elf_Shdr *sechdrs,
1381 unsigned int info,
1382 const char *tag)
1384 char *p;
1385 unsigned int taglen = strlen(tag);
1386 unsigned long size = sechdrs[info].sh_size;
1388 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1389 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1390 return p + taglen + 1;
1392 return NULL;
1395 #ifdef CONFIG_KALLSYMS
1396 int is_exported(const char *name, const struct module *mod)
1398 unsigned int i;
1400 if (!mod) {
1401 for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++)
1402 if (strcmp(__start___ksymtab[i].name, name) == 0)
1403 return 1;
1404 return 0;
1406 for (i = 0; i < mod->num_syms; i++)
1407 if (strcmp(mod->syms[i].name, name) == 0)
1408 return 1;
1409 return 0;
1412 /* As per nm */
1413 static char elf_type(const Elf_Sym *sym,
1414 Elf_Shdr *sechdrs,
1415 const char *secstrings,
1416 struct module *mod)
1418 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1419 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1420 return 'v';
1421 else
1422 return 'w';
1424 if (sym->st_shndx == SHN_UNDEF)
1425 return 'U';
1426 if (sym->st_shndx == SHN_ABS)
1427 return 'a';
1428 if (sym->st_shndx >= SHN_LORESERVE)
1429 return '?';
1430 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1431 return 't';
1432 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1433 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1434 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1435 return 'r';
1436 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1437 return 'g';
1438 else
1439 return 'd';
1441 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1442 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1443 return 's';
1444 else
1445 return 'b';
1447 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1448 ".debug", strlen(".debug")) == 0)
1449 return 'n';
1450 return '?';
1453 static void add_kallsyms(struct module *mod,
1454 Elf_Shdr *sechdrs,
1455 unsigned int symindex,
1456 unsigned int strindex,
1457 const char *secstrings)
1459 unsigned int i;
1461 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1462 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1463 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1465 /* Set types up while we still have access to sections. */
1466 for (i = 0; i < mod->num_symtab; i++)
1467 mod->symtab[i].st_info
1468 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1470 #else
1471 static inline void add_kallsyms(struct module *mod,
1472 Elf_Shdr *sechdrs,
1473 unsigned int symindex,
1474 unsigned int strindex,
1475 const char *secstrings)
1478 #endif /* CONFIG_KALLSYMS */
1480 /* Allocate and load the module: note that size of section 0 is always
1481 zero, and we rely on this for optional sections. */
1482 static struct module *load_module(void __user *umod,
1483 unsigned long len,
1484 const char __user *uargs)
1486 Elf_Ehdr *hdr;
1487 Elf_Shdr *sechdrs;
1488 char *secstrings, *args, *modmagic, *strtab = NULL;
1489 unsigned int i, symindex = 0, strindex = 0, setupindex, exindex,
1490 exportindex, modindex, obsparmindex, infoindex, gplindex,
1491 crcindex, gplcrcindex, versindex, pcpuindex;
1492 long arglen;
1493 struct module *mod;
1494 long err = 0;
1495 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1496 struct exception_table_entry *extable;
1498 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1499 umod, len, uargs);
1500 if (len < sizeof(*hdr))
1501 return ERR_PTR(-ENOEXEC);
1503 /* Suck in entire file: we'll want most of it. */
1504 /* vmalloc barfs on "unusual" numbers. Check here */
1505 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1506 return ERR_PTR(-ENOMEM);
1507 if (copy_from_user(hdr, umod, len) != 0) {
1508 err = -EFAULT;
1509 goto free_hdr;
1512 /* Sanity checks against insmoding binaries or wrong arch,
1513 weird elf version */
1514 if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
1515 || hdr->e_type != ET_REL
1516 || !elf_check_arch(hdr)
1517 || hdr->e_shentsize != sizeof(*sechdrs)) {
1518 err = -ENOEXEC;
1519 goto free_hdr;
1522 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1523 goto truncated;
1525 /* Convenience variables */
1526 sechdrs = (void *)hdr + hdr->e_shoff;
1527 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1528 sechdrs[0].sh_addr = 0;
1530 for (i = 1; i < hdr->e_shnum; i++) {
1531 if (sechdrs[i].sh_type != SHT_NOBITS
1532 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1533 goto truncated;
1535 /* Mark all sections sh_addr with their address in the
1536 temporary image. */
1537 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1539 /* Internal symbols and strings. */
1540 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1541 symindex = i;
1542 strindex = sechdrs[i].sh_link;
1543 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1545 #ifndef CONFIG_MODULE_UNLOAD
1546 /* Don't load .exit sections */
1547 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1548 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1549 #endif
1552 modindex = find_sec(hdr, sechdrs, secstrings,
1553 ".gnu.linkonce.this_module");
1554 if (!modindex) {
1555 printk(KERN_WARNING "No module found in object\n");
1556 err = -ENOEXEC;
1557 goto free_hdr;
1559 mod = (void *)sechdrs[modindex].sh_addr;
1561 if (symindex == 0) {
1562 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1563 mod->name);
1564 err = -ENOEXEC;
1565 goto free_hdr;
1568 /* Optional sections */
1569 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1570 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1571 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1572 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1573 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1574 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1575 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1576 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1577 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1578 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1580 /* Don't keep modinfo section */
1581 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1582 #ifdef CONFIG_KALLSYMS
1583 /* Keep symbol and string tables for decoding later. */
1584 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1585 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1586 #endif
1588 /* Check module struct version now, before we try to use module. */
1589 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1590 err = -ENOEXEC;
1591 goto free_hdr;
1594 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1595 /* This is allowed: modprobe --force will invalidate it. */
1596 if (!modmagic) {
1597 tainted |= TAINT_FORCED_MODULE;
1598 printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
1599 mod->name);
1600 } else if (!same_magic(modmagic, vermagic)) {
1601 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1602 mod->name, modmagic, vermagic);
1603 err = -ENOEXEC;
1604 goto free_hdr;
1607 /* Now copy in args */
1608 arglen = strlen_user(uargs);
1609 if (!arglen) {
1610 err = -EFAULT;
1611 goto free_hdr;
1613 args = kmalloc(arglen, GFP_KERNEL);
1614 if (!args) {
1615 err = -ENOMEM;
1616 goto free_hdr;
1618 if (copy_from_user(args, uargs, arglen) != 0) {
1619 err = -EFAULT;
1620 goto free_mod;
1623 if (find_module(mod->name)) {
1624 err = -EEXIST;
1625 goto free_mod;
1628 mod->state = MODULE_STATE_COMING;
1630 /* Allow arches to frob section contents and sizes. */
1631 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1632 if (err < 0)
1633 goto free_mod;
1635 if (pcpuindex) {
1636 /* We have a special allocation for this section. */
1637 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1638 sechdrs[pcpuindex].sh_addralign);
1639 if (!percpu) {
1640 err = -ENOMEM;
1641 goto free_mod;
1643 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1644 mod->percpu = percpu;
1647 /* Determine total sizes, and put offsets in sh_entsize. For now
1648 this is done generically; there doesn't appear to be any
1649 special cases for the architectures. */
1650 layout_sections(mod, hdr, sechdrs, secstrings);
1652 /* Do the allocs. */
1653 ptr = module_alloc(mod->core_size);
1654 if (!ptr) {
1655 err = -ENOMEM;
1656 goto free_percpu;
1658 memset(ptr, 0, mod->core_size);
1659 mod->module_core = ptr;
1661 ptr = module_alloc(mod->init_size);
1662 if (!ptr && mod->init_size) {
1663 err = -ENOMEM;
1664 goto free_core;
1666 memset(ptr, 0, mod->init_size);
1667 mod->module_init = ptr;
1669 /* Transfer each section which specifies SHF_ALLOC */
1670 DEBUGP("final section addresses:\n");
1671 for (i = 0; i < hdr->e_shnum; i++) {
1672 void *dest;
1674 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1675 continue;
1677 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
1678 dest = mod->module_init
1679 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
1680 else
1681 dest = mod->module_core + sechdrs[i].sh_entsize;
1683 if (sechdrs[i].sh_type != SHT_NOBITS)
1684 memcpy(dest, (void *)sechdrs[i].sh_addr,
1685 sechdrs[i].sh_size);
1686 /* Update sh_addr to point to copy in image. */
1687 sechdrs[i].sh_addr = (unsigned long)dest;
1688 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
1690 /* Module has been moved. */
1691 mod = (void *)sechdrs[modindex].sh_addr;
1693 /* Now we've moved module, initialize linked lists, etc. */
1694 module_unload_init(mod);
1696 /* Set up license info based on the info section */
1697 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
1699 /* Fix up syms, so that st_value is a pointer to location. */
1700 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
1701 mod);
1702 if (err < 0)
1703 goto cleanup;
1705 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
1706 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
1707 mod->syms = (void *)sechdrs[exportindex].sh_addr;
1708 if (crcindex)
1709 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
1710 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
1711 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
1712 if (gplcrcindex)
1713 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
1715 #ifdef CONFIG_MODVERSIONS
1716 if ((mod->num_syms && !crcindex) ||
1717 (mod->num_gpl_syms && !gplcrcindex)) {
1718 printk(KERN_WARNING "%s: No versions for exported symbols."
1719 " Tainting kernel.\n", mod->name);
1720 tainted |= TAINT_FORCED_MODULE;
1722 #endif
1724 /* Now do relocations. */
1725 for (i = 1; i < hdr->e_shnum; i++) {
1726 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1727 unsigned int info = sechdrs[i].sh_info;
1729 /* Not a valid relocation section? */
1730 if (info >= hdr->e_shnum)
1731 continue;
1733 /* Don't bother with non-allocated sections */
1734 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1735 continue;
1737 if (sechdrs[i].sh_type == SHT_REL)
1738 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
1739 else if (sechdrs[i].sh_type == SHT_RELA)
1740 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1741 mod);
1742 if (err < 0)
1743 goto cleanup;
1746 /* Set up and sort exception table */
1747 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
1748 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
1749 sort_extable(extable, extable + mod->num_exentries);
1751 /* Finally, copy percpu area over. */
1752 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
1753 sechdrs[pcpuindex].sh_size);
1755 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
1757 err = module_finalize(hdr, sechdrs, mod);
1758 if (err < 0)
1759 goto cleanup;
1761 mod->args = args;
1762 if (obsparmindex) {
1763 err = obsolete_params(mod->name, mod->args,
1764 (struct obsolete_modparm *)
1765 sechdrs[obsparmindex].sh_addr,
1766 sechdrs[obsparmindex].sh_size
1767 / sizeof(struct obsolete_modparm),
1768 sechdrs, symindex,
1769 (char *)sechdrs[strindex].sh_addr);
1770 if (setupindex)
1771 printk(KERN_WARNING "%s: Ignoring new-style "
1772 "parameters in presence of obsolete ones\n",
1773 mod->name);
1774 } else {
1775 /* Size of section 0 is 0, so this works well if no params */
1776 err = parse_args(mod->name, mod->args,
1777 (struct kernel_param *)
1778 sechdrs[setupindex].sh_addr,
1779 sechdrs[setupindex].sh_size
1780 / sizeof(struct kernel_param),
1781 NULL);
1783 err = mod_sysfs_setup(mod,
1784 (struct kernel_param *)
1785 sechdrs[setupindex].sh_addr,
1786 sechdrs[setupindex].sh_size
1787 / sizeof(struct kernel_param));
1788 if (err < 0)
1789 goto arch_cleanup;
1790 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
1792 /* Get rid of temporary copy */
1793 vfree(hdr);
1795 /* Done! */
1796 return mod;
1798 arch_cleanup:
1799 module_arch_cleanup(mod);
1800 cleanup:
1801 module_unload_free(mod);
1802 module_free(mod, mod->module_init);
1803 free_core:
1804 module_free(mod, mod->module_core);
1805 free_percpu:
1806 if (percpu)
1807 percpu_modfree(percpu);
1808 free_mod:
1809 kfree(args);
1810 free_hdr:
1811 vfree(hdr);
1812 if (err < 0) return ERR_PTR(err);
1813 else return ptr;
1815 truncated:
1816 printk(KERN_ERR "Module len %lu truncated\n", len);
1817 err = -ENOEXEC;
1818 goto free_hdr;
1821 /* This is where the real work happens */
1822 asmlinkage long
1823 sys_init_module(void __user *umod,
1824 unsigned long len,
1825 const char __user *uargs)
1827 struct module *mod;
1828 int ret = 0;
1830 /* Must have permission */
1831 if (!capable(CAP_SYS_MODULE))
1832 return -EPERM;
1834 /* Only one module load at a time, please */
1835 if (down_interruptible(&module_mutex) != 0)
1836 return -EINTR;
1838 /* Do all the hard work */
1839 mod = load_module(umod, len, uargs);
1840 if (IS_ERR(mod)) {
1841 up(&module_mutex);
1842 return PTR_ERR(mod);
1845 /* Flush the instruction cache, since we've played with text */
1846 if (mod->module_init)
1847 flush_icache_range((unsigned long)mod->module_init,
1848 (unsigned long)mod->module_init
1849 + mod->init_size);
1850 flush_icache_range((unsigned long)mod->module_core,
1851 (unsigned long)mod->module_core + mod->core_size);
1853 /* Now sew it into the lists. They won't access us, since
1854 strong_try_module_get() will fail. */
1855 spin_lock_irq(&modlist_lock);
1856 list_add(&mod->list, &modules);
1857 spin_unlock_irq(&modlist_lock);
1859 /* Drop lock so they can recurse */
1860 up(&module_mutex);
1862 down(&notify_mutex);
1863 notifier_call_chain(&module_notify_list, MODULE_STATE_COMING, mod);
1864 up(&notify_mutex);
1866 /* Start the module */
1867 if (mod->init != NULL)
1868 ret = mod->init();
1869 if (ret < 0) {
1870 /* Init routine failed: abort. Try to protect us from
1871 buggy refcounters. */
1872 mod->state = MODULE_STATE_GOING;
1873 synchronize_kernel();
1874 if (mod->unsafe)
1875 printk(KERN_ERR "%s: module is now stuck!\n",
1876 mod->name);
1877 else {
1878 module_put(mod);
1879 down(&module_mutex);
1880 free_module(mod);
1881 up(&module_mutex);
1883 return ret;
1886 /* Now it's a first class citizen! */
1887 down(&module_mutex);
1888 mod->state = MODULE_STATE_LIVE;
1889 /* Drop initial reference. */
1890 module_put(mod);
1891 module_free(mod, mod->module_init);
1892 mod->module_init = NULL;
1893 mod->init_size = 0;
1894 mod->init_text_size = 0;
1895 up(&module_mutex);
1897 return 0;
1900 static inline int within(unsigned long addr, void *start, unsigned long size)
1902 return ((void *)addr >= start && (void *)addr < start + size);
1905 #ifdef CONFIG_KALLSYMS
1906 static const char *get_ksymbol(struct module *mod,
1907 unsigned long addr,
1908 unsigned long *size,
1909 unsigned long *offset)
1911 unsigned int i, best = 0;
1912 unsigned long nextval;
1914 /* At worse, next value is at end of module */
1915 if (within(addr, mod->module_init, mod->init_size))
1916 nextval = (unsigned long)mod->module_init+mod->init_text_size;
1917 else
1918 nextval = (unsigned long)mod->module_core+mod->core_text_size;
1920 /* Scan for closest preceeding symbol, and next symbol. (ELF
1921 starts real symbols at 1). */
1922 for (i = 1; i < mod->num_symtab; i++) {
1923 if (mod->symtab[i].st_shndx == SHN_UNDEF)
1924 continue;
1926 /* We ignore unnamed symbols: they're uninformative
1927 * and inserted at a whim. */
1928 if (mod->symtab[i].st_value <= addr
1929 && mod->symtab[i].st_value > mod->symtab[best].st_value
1930 && *(mod->strtab + mod->symtab[i].st_name) != '\0' )
1931 best = i;
1932 if (mod->symtab[i].st_value > addr
1933 && mod->symtab[i].st_value < nextval
1934 && *(mod->strtab + mod->symtab[i].st_name) != '\0')
1935 nextval = mod->symtab[i].st_value;
1938 if (!best)
1939 return NULL;
1941 *size = nextval - mod->symtab[best].st_value;
1942 *offset = addr - mod->symtab[best].st_value;
1943 return mod->strtab + mod->symtab[best].st_name;
1946 /* For kallsyms to ask for address resolution. NULL means not found.
1947 We don't lock, as this is used for oops resolution and races are a
1948 lesser concern. */
1949 const char *module_address_lookup(unsigned long addr,
1950 unsigned long *size,
1951 unsigned long *offset,
1952 char **modname)
1954 struct module *mod;
1956 list_for_each_entry(mod, &modules, list) {
1957 if (within(addr, mod->module_init, mod->init_size)
1958 || within(addr, mod->module_core, mod->core_size)) {
1959 *modname = mod->name;
1960 return get_ksymbol(mod, addr, size, offset);
1963 return NULL;
1966 struct module *module_get_kallsym(unsigned int symnum,
1967 unsigned long *value,
1968 char *type,
1969 char namebuf[128])
1971 struct module *mod;
1973 down(&module_mutex);
1974 list_for_each_entry(mod, &modules, list) {
1975 if (symnum < mod->num_symtab) {
1976 *value = mod->symtab[symnum].st_value;
1977 *type = mod->symtab[symnum].st_info;
1978 strncpy(namebuf,
1979 mod->strtab + mod->symtab[symnum].st_name,
1980 127);
1981 up(&module_mutex);
1982 return mod;
1984 symnum -= mod->num_symtab;
1986 up(&module_mutex);
1987 return NULL;
1990 static unsigned long mod_find_symname(struct module *mod, const char *name)
1992 unsigned int i;
1994 for (i = 0; i < mod->num_symtab; i++)
1995 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0)
1996 return mod->symtab[i].st_value;
1997 return 0;
2000 /* Look for this name: can be of form module:name. */
2001 unsigned long module_kallsyms_lookup_name(const char *name)
2003 struct module *mod;
2004 char *colon;
2005 unsigned long ret = 0;
2007 /* Don't lock: we're in enough trouble already. */
2008 if ((colon = strchr(name, ':')) != NULL) {
2009 *colon = '\0';
2010 if ((mod = find_module(name)) != NULL)
2011 ret = mod_find_symname(mod, colon+1);
2012 *colon = ':';
2013 } else {
2014 list_for_each_entry(mod, &modules, list)
2015 if ((ret = mod_find_symname(mod, name)) != 0)
2016 break;
2018 return ret;
2020 #endif /* CONFIG_KALLSYMS */
2022 /* Called by the /proc file system to return a list of modules. */
2023 static void *m_start(struct seq_file *m, loff_t *pos)
2025 struct list_head *i;
2026 loff_t n = 0;
2028 down(&module_mutex);
2029 list_for_each(i, &modules) {
2030 if (n++ == *pos)
2031 break;
2033 if (i == &modules)
2034 return NULL;
2035 return i;
2038 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2040 struct list_head *i = p;
2041 (*pos)++;
2042 if (i->next == &modules)
2043 return NULL;
2044 return i->next;
2047 static void m_stop(struct seq_file *m, void *p)
2049 up(&module_mutex);
2052 static int m_show(struct seq_file *m, void *p)
2054 struct module *mod = list_entry(p, struct module, list);
2055 seq_printf(m, "%s %lu",
2056 mod->name, mod->init_size + mod->core_size);
2057 print_unload_info(m, mod);
2059 /* Informative for users. */
2060 seq_printf(m, " %s",
2061 mod->state == MODULE_STATE_GOING ? "Unloading":
2062 mod->state == MODULE_STATE_COMING ? "Loading":
2063 "Live");
2064 /* Used by oprofile and other similar tools. */
2065 seq_printf(m, " 0x%p", mod->module_core);
2067 seq_printf(m, "\n");
2068 return 0;
2071 /* Format: modulename size refcount deps address
2073 Where refcount is a number or -, and deps is a comma-separated list
2074 of depends or -.
2076 struct seq_operations modules_op = {
2077 .start = m_start,
2078 .next = m_next,
2079 .stop = m_stop,
2080 .show = m_show
2083 /* Given an address, look for it in the module exception tables. */
2084 const struct exception_table_entry *search_module_extables(unsigned long addr)
2086 unsigned long flags;
2087 const struct exception_table_entry *e = NULL;
2088 struct module *mod;
2090 spin_lock_irqsave(&modlist_lock, flags);
2091 list_for_each_entry(mod, &modules, list) {
2092 if (mod->num_exentries == 0)
2093 continue;
2095 e = search_extable(mod->extable,
2096 mod->extable + mod->num_exentries - 1,
2097 addr);
2098 if (e)
2099 break;
2101 spin_unlock_irqrestore(&modlist_lock, flags);
2103 /* Now, if we found one, we are running inside it now, hence
2104 we cannot unload the module, hence no refcnt needed. */
2105 return e;
2108 /* Is this a valid kernel address? We don't grab the lock: we are oopsing. */
2109 struct module *__module_text_address(unsigned long addr)
2111 struct module *mod;
2113 list_for_each_entry(mod, &modules, list)
2114 if (within(addr, mod->module_init, mod->init_text_size)
2115 || within(addr, mod->module_core, mod->core_text_size))
2116 return mod;
2117 return NULL;
2120 struct module *module_text_address(unsigned long addr)
2122 struct module *mod;
2123 unsigned long flags;
2125 spin_lock_irqsave(&modlist_lock, flags);
2126 mod = __module_text_address(addr);
2127 spin_unlock_irqrestore(&modlist_lock, flags);
2129 return mod;
2132 /* Don't grab lock, we're oopsing. */
2133 void print_modules(void)
2135 struct module *mod;
2137 printk("Modules linked in:");
2138 list_for_each_entry(mod, &modules, list)
2139 printk(" %s", mod->name);
2140 printk("\n");
2143 #ifdef CONFIG_MODVERSIONS
2144 /* Generate the signature for struct module here, too, for modversions. */
2145 void struct_module(struct module *mod) { return; }
2146 EXPORT_SYMBOL(struct_module);
2147 #endif
2149 static int __init modules_init(void)
2151 return subsystem_register(&module_subsys);
2153 __initcall(modules_init);