[S390] console: allow vt220 console to be the only console
[linux/fpc-iii.git] / kernel / module.c
blobbd60278ee7035945d1db4dfaed0f26b3c4a457e8
1 /*
2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 #include <linux/module.h>
20 #include <linux/moduleloader.h>
21 #include <linux/init.h>
22 #include <linux/kallsyms.h>
23 #include <linux/sysfs.h>
24 #include <linux/kernel.h>
25 #include <linux/slab.h>
26 #include <linux/vmalloc.h>
27 #include <linux/elf.h>
28 #include <linux/seq_file.h>
29 #include <linux/syscalls.h>
30 #include <linux/fcntl.h>
31 #include <linux/rcupdate.h>
32 #include <linux/capability.h>
33 #include <linux/cpu.h>
34 #include <linux/moduleparam.h>
35 #include <linux/errno.h>
36 #include <linux/err.h>
37 #include <linux/vermagic.h>
38 #include <linux/notifier.h>
39 #include <linux/sched.h>
40 #include <linux/stop_machine.h>
41 #include <linux/device.h>
42 #include <linux/string.h>
43 #include <linux/mutex.h>
44 #include <linux/unwind.h>
45 #include <asm/uaccess.h>
46 #include <asm/semaphore.h>
47 #include <asm/cacheflush.h>
48 #include <linux/license.h>
50 #if 0
51 #define DEBUGP printk
52 #else
53 #define DEBUGP(fmt , a...)
54 #endif
56 #ifndef ARCH_SHF_SMALL
57 #define ARCH_SHF_SMALL 0
58 #endif
60 /* If this is set, the section belongs in the init part of the module */
61 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
63 /* List of modules, protected by module_mutex or preempt_disable
64 * (add/delete uses stop_machine). */
65 static DEFINE_MUTEX(module_mutex);
66 static LIST_HEAD(modules);
68 /* Waiting for a module to finish initializing? */
69 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
71 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
73 int register_module_notifier(struct notifier_block * nb)
75 return blocking_notifier_chain_register(&module_notify_list, nb);
77 EXPORT_SYMBOL(register_module_notifier);
79 int unregister_module_notifier(struct notifier_block * nb)
81 return blocking_notifier_chain_unregister(&module_notify_list, nb);
83 EXPORT_SYMBOL(unregister_module_notifier);
85 /* We require a truly strong try_module_get(): 0 means failure due to
86 ongoing or failed initialization etc. */
87 static inline int strong_try_module_get(struct module *mod)
89 if (mod && mod->state == MODULE_STATE_COMING)
90 return -EBUSY;
91 if (try_module_get(mod))
92 return 0;
93 else
94 return -ENOENT;
97 static inline void add_taint_module(struct module *mod, unsigned flag)
99 add_taint(flag);
100 mod->taints |= flag;
104 * A thread that wants to hold a reference to a module only while it
105 * is running can call this to safely exit. nfsd and lockd use this.
107 void __module_put_and_exit(struct module *mod, long code)
109 module_put(mod);
110 do_exit(code);
112 EXPORT_SYMBOL(__module_put_and_exit);
114 /* Find a module section: 0 means not found. */
115 static unsigned int find_sec(Elf_Ehdr *hdr,
116 Elf_Shdr *sechdrs,
117 const char *secstrings,
118 const char *name)
120 unsigned int i;
122 for (i = 1; i < hdr->e_shnum; i++)
123 /* Alloc bit cleared means "ignore it." */
124 if ((sechdrs[i].sh_flags & SHF_ALLOC)
125 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
126 return i;
127 return 0;
130 /* Provided by the linker */
131 extern const struct kernel_symbol __start___ksymtab[];
132 extern const struct kernel_symbol __stop___ksymtab[];
133 extern const struct kernel_symbol __start___ksymtab_gpl[];
134 extern const struct kernel_symbol __stop___ksymtab_gpl[];
135 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
136 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
137 extern const struct kernel_symbol __start___ksymtab_unused[];
138 extern const struct kernel_symbol __stop___ksymtab_unused[];
139 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
140 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
141 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
142 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
143 extern const unsigned long __start___kcrctab[];
144 extern const unsigned long __start___kcrctab_gpl[];
145 extern const unsigned long __start___kcrctab_gpl_future[];
146 extern const unsigned long __start___kcrctab_unused[];
147 extern const unsigned long __start___kcrctab_unused_gpl[];
149 #ifndef CONFIG_MODVERSIONS
150 #define symversion(base, idx) NULL
151 #else
152 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
153 #endif
155 /* lookup symbol in given range of kernel_symbols */
156 static const struct kernel_symbol *lookup_symbol(const char *name,
157 const struct kernel_symbol *start,
158 const struct kernel_symbol *stop)
160 const struct kernel_symbol *ks = start;
161 for (; ks < stop; ks++)
162 if (strcmp(ks->name, name) == 0)
163 return ks;
164 return NULL;
167 static void printk_unused_warning(const char *name)
169 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
170 "however this module is using it.\n", name);
171 printk(KERN_WARNING "This symbol will go away in the future.\n");
172 printk(KERN_WARNING "Please evalute if this is the right api to use, "
173 "and if it really is, submit a report the linux kernel "
174 "mailinglist together with submitting your code for "
175 "inclusion.\n");
178 /* Find a symbol, return value, crc and module which owns it */
179 static unsigned long __find_symbol(const char *name,
180 struct module **owner,
181 const unsigned long **crc,
182 int gplok)
184 struct module *mod;
185 const struct kernel_symbol *ks;
187 /* Core kernel first. */
188 *owner = NULL;
189 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
190 if (ks) {
191 *crc = symversion(__start___kcrctab, (ks - __start___ksymtab));
192 return ks->value;
194 if (gplok) {
195 ks = lookup_symbol(name, __start___ksymtab_gpl,
196 __stop___ksymtab_gpl);
197 if (ks) {
198 *crc = symversion(__start___kcrctab_gpl,
199 (ks - __start___ksymtab_gpl));
200 return ks->value;
203 ks = lookup_symbol(name, __start___ksymtab_gpl_future,
204 __stop___ksymtab_gpl_future);
205 if (ks) {
206 if (!gplok) {
207 printk(KERN_WARNING "Symbol %s is being used "
208 "by a non-GPL module, which will not "
209 "be allowed in the future\n", name);
210 printk(KERN_WARNING "Please see the file "
211 "Documentation/feature-removal-schedule.txt "
212 "in the kernel source tree for more "
213 "details.\n");
215 *crc = symversion(__start___kcrctab_gpl_future,
216 (ks - __start___ksymtab_gpl_future));
217 return ks->value;
220 ks = lookup_symbol(name, __start___ksymtab_unused,
221 __stop___ksymtab_unused);
222 if (ks) {
223 printk_unused_warning(name);
224 *crc = symversion(__start___kcrctab_unused,
225 (ks - __start___ksymtab_unused));
226 return ks->value;
229 if (gplok)
230 ks = lookup_symbol(name, __start___ksymtab_unused_gpl,
231 __stop___ksymtab_unused_gpl);
232 if (ks) {
233 printk_unused_warning(name);
234 *crc = symversion(__start___kcrctab_unused_gpl,
235 (ks - __start___ksymtab_unused_gpl));
236 return ks->value;
239 /* Now try modules. */
240 list_for_each_entry(mod, &modules, list) {
241 *owner = mod;
242 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
243 if (ks) {
244 *crc = symversion(mod->crcs, (ks - mod->syms));
245 return ks->value;
248 if (gplok) {
249 ks = lookup_symbol(name, mod->gpl_syms,
250 mod->gpl_syms + mod->num_gpl_syms);
251 if (ks) {
252 *crc = symversion(mod->gpl_crcs,
253 (ks - mod->gpl_syms));
254 return ks->value;
257 ks = lookup_symbol(name, mod->unused_syms, mod->unused_syms + mod->num_unused_syms);
258 if (ks) {
259 printk_unused_warning(name);
260 *crc = symversion(mod->unused_crcs, (ks - mod->unused_syms));
261 return ks->value;
264 if (gplok) {
265 ks = lookup_symbol(name, mod->unused_gpl_syms,
266 mod->unused_gpl_syms + mod->num_unused_gpl_syms);
267 if (ks) {
268 printk_unused_warning(name);
269 *crc = symversion(mod->unused_gpl_crcs,
270 (ks - mod->unused_gpl_syms));
271 return ks->value;
274 ks = lookup_symbol(name, mod->gpl_future_syms,
275 (mod->gpl_future_syms +
276 mod->num_gpl_future_syms));
277 if (ks) {
278 if (!gplok) {
279 printk(KERN_WARNING "Symbol %s is being used "
280 "by a non-GPL module, which will not "
281 "be allowed in the future\n", name);
282 printk(KERN_WARNING "Please see the file "
283 "Documentation/feature-removal-schedule.txt "
284 "in the kernel source tree for more "
285 "details.\n");
287 *crc = symversion(mod->gpl_future_crcs,
288 (ks - mod->gpl_future_syms));
289 return ks->value;
292 DEBUGP("Failed to find symbol %s\n", name);
293 return 0;
296 /* Search for module by name: must hold module_mutex. */
297 static struct module *find_module(const char *name)
299 struct module *mod;
301 list_for_each_entry(mod, &modules, list) {
302 if (strcmp(mod->name, name) == 0)
303 return mod;
305 return NULL;
308 #ifdef CONFIG_SMP
309 /* Number of blocks used and allocated. */
310 static unsigned int pcpu_num_used, pcpu_num_allocated;
311 /* Size of each block. -ve means used. */
312 static int *pcpu_size;
314 static int split_block(unsigned int i, unsigned short size)
316 /* Reallocation required? */
317 if (pcpu_num_used + 1 > pcpu_num_allocated) {
318 int *new;
320 new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2,
321 GFP_KERNEL);
322 if (!new)
323 return 0;
325 pcpu_num_allocated *= 2;
326 pcpu_size = new;
329 /* Insert a new subblock */
330 memmove(&pcpu_size[i+1], &pcpu_size[i],
331 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
332 pcpu_num_used++;
334 pcpu_size[i+1] -= size;
335 pcpu_size[i] = size;
336 return 1;
339 static inline unsigned int block_size(int val)
341 if (val < 0)
342 return -val;
343 return val;
346 /* Created by linker magic */
347 extern char __per_cpu_start[], __per_cpu_end[];
349 static void *percpu_modalloc(unsigned long size, unsigned long align,
350 const char *name)
352 unsigned long extra;
353 unsigned int i;
354 void *ptr;
356 if (align > PAGE_SIZE) {
357 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
358 name, align, PAGE_SIZE);
359 align = PAGE_SIZE;
362 ptr = __per_cpu_start;
363 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
364 /* Extra for alignment requirement. */
365 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
366 BUG_ON(i == 0 && extra != 0);
368 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
369 continue;
371 /* Transfer extra to previous block. */
372 if (pcpu_size[i-1] < 0)
373 pcpu_size[i-1] -= extra;
374 else
375 pcpu_size[i-1] += extra;
376 pcpu_size[i] -= extra;
377 ptr += extra;
379 /* Split block if warranted */
380 if (pcpu_size[i] - size > sizeof(unsigned long))
381 if (!split_block(i, size))
382 return NULL;
384 /* Mark allocated */
385 pcpu_size[i] = -pcpu_size[i];
386 return ptr;
389 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
390 size);
391 return NULL;
394 static void percpu_modfree(void *freeme)
396 unsigned int i;
397 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
399 /* First entry is core kernel percpu data. */
400 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
401 if (ptr == freeme) {
402 pcpu_size[i] = -pcpu_size[i];
403 goto free;
406 BUG();
408 free:
409 /* Merge with previous? */
410 if (pcpu_size[i-1] >= 0) {
411 pcpu_size[i-1] += pcpu_size[i];
412 pcpu_num_used--;
413 memmove(&pcpu_size[i], &pcpu_size[i+1],
414 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
415 i--;
417 /* Merge with next? */
418 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
419 pcpu_size[i] += pcpu_size[i+1];
420 pcpu_num_used--;
421 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
422 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
426 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
427 Elf_Shdr *sechdrs,
428 const char *secstrings)
430 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
433 static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
435 int cpu;
437 for_each_possible_cpu(cpu)
438 memcpy(pcpudest + per_cpu_offset(cpu), from, size);
441 static int percpu_modinit(void)
443 pcpu_num_used = 2;
444 pcpu_num_allocated = 2;
445 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
446 GFP_KERNEL);
447 /* Static in-kernel percpu data (used). */
448 pcpu_size[0] = -(__per_cpu_end-__per_cpu_start);
449 /* Free room. */
450 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
451 if (pcpu_size[1] < 0) {
452 printk(KERN_ERR "No per-cpu room for modules.\n");
453 pcpu_num_used = 1;
456 return 0;
458 __initcall(percpu_modinit);
459 #else /* ... !CONFIG_SMP */
460 static inline void *percpu_modalloc(unsigned long size, unsigned long align,
461 const char *name)
463 return NULL;
465 static inline void percpu_modfree(void *pcpuptr)
467 BUG();
469 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
470 Elf_Shdr *sechdrs,
471 const char *secstrings)
473 return 0;
475 static inline void percpu_modcopy(void *pcpudst, const void *src,
476 unsigned long size)
478 /* pcpusec should be 0, and size of that section should be 0. */
479 BUG_ON(size != 0);
481 #endif /* CONFIG_SMP */
483 #define MODINFO_ATTR(field) \
484 static void setup_modinfo_##field(struct module *mod, const char *s) \
486 mod->field = kstrdup(s, GFP_KERNEL); \
488 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
489 struct module *mod, char *buffer) \
491 return sprintf(buffer, "%s\n", mod->field); \
493 static int modinfo_##field##_exists(struct module *mod) \
495 return mod->field != NULL; \
497 static void free_modinfo_##field(struct module *mod) \
499 kfree(mod->field); \
500 mod->field = NULL; \
502 static struct module_attribute modinfo_##field = { \
503 .attr = { .name = __stringify(field), .mode = 0444 }, \
504 .show = show_modinfo_##field, \
505 .setup = setup_modinfo_##field, \
506 .test = modinfo_##field##_exists, \
507 .free = free_modinfo_##field, \
510 MODINFO_ATTR(version);
511 MODINFO_ATTR(srcversion);
513 static char last_unloaded_module[MODULE_NAME_LEN+1];
515 #ifdef CONFIG_MODULE_UNLOAD
516 /* Init the unload section of the module. */
517 static void module_unload_init(struct module *mod)
519 unsigned int i;
521 INIT_LIST_HEAD(&mod->modules_which_use_me);
522 for (i = 0; i < NR_CPUS; i++)
523 local_set(&mod->ref[i].count, 0);
524 /* Hold reference count during initialization. */
525 local_set(&mod->ref[raw_smp_processor_id()].count, 1);
526 /* Backwards compatibility macros put refcount during init. */
527 mod->waiter = current;
530 /* modules using other modules */
531 struct module_use
533 struct list_head list;
534 struct module *module_which_uses;
537 /* Does a already use b? */
538 static int already_uses(struct module *a, struct module *b)
540 struct module_use *use;
542 list_for_each_entry(use, &b->modules_which_use_me, list) {
543 if (use->module_which_uses == a) {
544 DEBUGP("%s uses %s!\n", a->name, b->name);
545 return 1;
548 DEBUGP("%s does not use %s!\n", a->name, b->name);
549 return 0;
552 /* Module a uses b */
553 static int use_module(struct module *a, struct module *b)
555 struct module_use *use;
556 int no_warn, err;
558 if (b == NULL || already_uses(a, b)) return 1;
560 /* If we're interrupted or time out, we fail. */
561 if (wait_event_interruptible_timeout(
562 module_wq, (err = strong_try_module_get(b)) != -EBUSY,
563 30 * HZ) <= 0) {
564 printk("%s: gave up waiting for init of module %s.\n",
565 a->name, b->name);
566 return 0;
569 /* If strong_try_module_get() returned a different error, we fail. */
570 if (err)
571 return 0;
573 DEBUGP("Allocating new usage for %s.\n", a->name);
574 use = kmalloc(sizeof(*use), GFP_ATOMIC);
575 if (!use) {
576 printk("%s: out of memory loading\n", a->name);
577 module_put(b);
578 return 0;
581 use->module_which_uses = a;
582 list_add(&use->list, &b->modules_which_use_me);
583 no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
584 return 1;
587 /* Clear the unload stuff of the module. */
588 static void module_unload_free(struct module *mod)
590 struct module *i;
592 list_for_each_entry(i, &modules, list) {
593 struct module_use *use;
595 list_for_each_entry(use, &i->modules_which_use_me, list) {
596 if (use->module_which_uses == mod) {
597 DEBUGP("%s unusing %s\n", mod->name, i->name);
598 module_put(i);
599 list_del(&use->list);
600 kfree(use);
601 sysfs_remove_link(i->holders_dir, mod->name);
602 /* There can be at most one match. */
603 break;
609 #ifdef CONFIG_MODULE_FORCE_UNLOAD
610 static inline int try_force_unload(unsigned int flags)
612 int ret = (flags & O_TRUNC);
613 if (ret)
614 add_taint(TAINT_FORCED_RMMOD);
615 return ret;
617 #else
618 static inline int try_force_unload(unsigned int flags)
620 return 0;
622 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
624 struct stopref
626 struct module *mod;
627 int flags;
628 int *forced;
631 /* Whole machine is stopped with interrupts off when this runs. */
632 static int __try_stop_module(void *_sref)
634 struct stopref *sref = _sref;
636 /* If it's not unused, quit unless we are told to block. */
637 if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
638 if (!(*sref->forced = try_force_unload(sref->flags)))
639 return -EWOULDBLOCK;
642 /* Mark it as dying. */
643 sref->mod->state = MODULE_STATE_GOING;
644 return 0;
647 static int try_stop_module(struct module *mod, int flags, int *forced)
649 struct stopref sref = { mod, flags, forced };
651 return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
654 unsigned int module_refcount(struct module *mod)
656 unsigned int i, total = 0;
658 for (i = 0; i < NR_CPUS; i++)
659 total += local_read(&mod->ref[i].count);
660 return total;
662 EXPORT_SYMBOL(module_refcount);
664 /* This exists whether we can unload or not */
665 static void free_module(struct module *mod);
667 static void wait_for_zero_refcount(struct module *mod)
669 /* Since we might sleep for some time, drop the semaphore first */
670 mutex_unlock(&module_mutex);
671 for (;;) {
672 DEBUGP("Looking at refcount...\n");
673 set_current_state(TASK_UNINTERRUPTIBLE);
674 if (module_refcount(mod) == 0)
675 break;
676 schedule();
678 current->state = TASK_RUNNING;
679 mutex_lock(&module_mutex);
682 asmlinkage long
683 sys_delete_module(const char __user *name_user, unsigned int flags)
685 struct module *mod;
686 char name[MODULE_NAME_LEN];
687 int ret, forced = 0;
689 if (!capable(CAP_SYS_MODULE))
690 return -EPERM;
692 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
693 return -EFAULT;
694 name[MODULE_NAME_LEN-1] = '\0';
696 if (mutex_lock_interruptible(&module_mutex) != 0)
697 return -EINTR;
699 mod = find_module(name);
700 if (!mod) {
701 ret = -ENOENT;
702 goto out;
705 if (!list_empty(&mod->modules_which_use_me)) {
706 /* Other modules depend on us: get rid of them first. */
707 ret = -EWOULDBLOCK;
708 goto out;
711 /* Doing init or already dying? */
712 if (mod->state != MODULE_STATE_LIVE) {
713 /* FIXME: if (force), slam module count and wake up
714 waiter --RR */
715 DEBUGP("%s already dying\n", mod->name);
716 ret = -EBUSY;
717 goto out;
720 /* If it has an init func, it must have an exit func to unload */
721 if (mod->init && !mod->exit) {
722 forced = try_force_unload(flags);
723 if (!forced) {
724 /* This module can't be removed */
725 ret = -EBUSY;
726 goto out;
730 /* Set this up before setting mod->state */
731 mod->waiter = current;
733 /* Stop the machine so refcounts can't move and disable module. */
734 ret = try_stop_module(mod, flags, &forced);
735 if (ret != 0)
736 goto out;
738 /* Never wait if forced. */
739 if (!forced && module_refcount(mod) != 0)
740 wait_for_zero_refcount(mod);
742 /* Final destruction now noone is using it. */
743 if (mod->exit != NULL) {
744 mutex_unlock(&module_mutex);
745 mod->exit();
746 mutex_lock(&module_mutex);
748 /* Store the name of the last unloaded module for diagnostic purposes */
749 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
750 free_module(mod);
752 out:
753 mutex_unlock(&module_mutex);
754 return ret;
757 static void print_unload_info(struct seq_file *m, struct module *mod)
759 struct module_use *use;
760 int printed_something = 0;
762 seq_printf(m, " %u ", module_refcount(mod));
764 /* Always include a trailing , so userspace can differentiate
765 between this and the old multi-field proc format. */
766 list_for_each_entry(use, &mod->modules_which_use_me, list) {
767 printed_something = 1;
768 seq_printf(m, "%s,", use->module_which_uses->name);
771 if (mod->init != NULL && mod->exit == NULL) {
772 printed_something = 1;
773 seq_printf(m, "[permanent],");
776 if (!printed_something)
777 seq_printf(m, "-");
780 void __symbol_put(const char *symbol)
782 struct module *owner;
783 const unsigned long *crc;
785 preempt_disable();
786 if (!__find_symbol(symbol, &owner, &crc, 1))
787 BUG();
788 module_put(owner);
789 preempt_enable();
791 EXPORT_SYMBOL(__symbol_put);
793 void symbol_put_addr(void *addr)
795 struct module *modaddr;
797 if (core_kernel_text((unsigned long)addr))
798 return;
800 if (!(modaddr = module_text_address((unsigned long)addr)))
801 BUG();
802 module_put(modaddr);
804 EXPORT_SYMBOL_GPL(symbol_put_addr);
806 static ssize_t show_refcnt(struct module_attribute *mattr,
807 struct module *mod, char *buffer)
809 return sprintf(buffer, "%u\n", module_refcount(mod));
812 static struct module_attribute refcnt = {
813 .attr = { .name = "refcnt", .mode = 0444 },
814 .show = show_refcnt,
817 void module_put(struct module *module)
819 if (module) {
820 unsigned int cpu = get_cpu();
821 local_dec(&module->ref[cpu].count);
822 /* Maybe they're waiting for us to drop reference? */
823 if (unlikely(!module_is_live(module)))
824 wake_up_process(module->waiter);
825 put_cpu();
828 EXPORT_SYMBOL(module_put);
830 #else /* !CONFIG_MODULE_UNLOAD */
831 static void print_unload_info(struct seq_file *m, struct module *mod)
833 /* We don't know the usage count, or what modules are using. */
834 seq_printf(m, " - -");
837 static inline void module_unload_free(struct module *mod)
841 static inline int use_module(struct module *a, struct module *b)
843 return strong_try_module_get(b) == 0;
846 static inline void module_unload_init(struct module *mod)
849 #endif /* CONFIG_MODULE_UNLOAD */
851 static ssize_t show_initstate(struct module_attribute *mattr,
852 struct module *mod, char *buffer)
854 const char *state = "unknown";
856 switch (mod->state) {
857 case MODULE_STATE_LIVE:
858 state = "live";
859 break;
860 case MODULE_STATE_COMING:
861 state = "coming";
862 break;
863 case MODULE_STATE_GOING:
864 state = "going";
865 break;
867 return sprintf(buffer, "%s\n", state);
870 static struct module_attribute initstate = {
871 .attr = { .name = "initstate", .mode = 0444 },
872 .show = show_initstate,
875 static struct module_attribute *modinfo_attrs[] = {
876 &modinfo_version,
877 &modinfo_srcversion,
878 &initstate,
879 #ifdef CONFIG_MODULE_UNLOAD
880 &refcnt,
881 #endif
882 NULL,
885 static const char vermagic[] = VERMAGIC_STRING;
887 #ifdef CONFIG_MODVERSIONS
888 static int check_version(Elf_Shdr *sechdrs,
889 unsigned int versindex,
890 const char *symname,
891 struct module *mod,
892 const unsigned long *crc)
894 unsigned int i, num_versions;
895 struct modversion_info *versions;
897 /* Exporting module didn't supply crcs? OK, we're already tainted. */
898 if (!crc)
899 return 1;
901 versions = (void *) sechdrs[versindex].sh_addr;
902 num_versions = sechdrs[versindex].sh_size
903 / sizeof(struct modversion_info);
905 for (i = 0; i < num_versions; i++) {
906 if (strcmp(versions[i].name, symname) != 0)
907 continue;
909 if (versions[i].crc == *crc)
910 return 1;
911 printk("%s: disagrees about version of symbol %s\n",
912 mod->name, symname);
913 DEBUGP("Found checksum %lX vs module %lX\n",
914 *crc, versions[i].crc);
915 return 0;
917 /* Not in module's version table. OK, but that taints the kernel. */
918 if (!(tainted & TAINT_FORCED_MODULE))
919 printk("%s: no version for \"%s\" found: kernel tainted.\n",
920 mod->name, symname);
921 add_taint_module(mod, TAINT_FORCED_MODULE);
922 return 1;
925 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
926 unsigned int versindex,
927 struct module *mod)
929 const unsigned long *crc;
930 struct module *owner;
932 if (!__find_symbol("struct_module", &owner, &crc, 1))
933 BUG();
934 return check_version(sechdrs, versindex, "struct_module", mod,
935 crc);
938 /* First part is kernel version, which we ignore. */
939 static inline int same_magic(const char *amagic, const char *bmagic)
941 amagic += strcspn(amagic, " ");
942 bmagic += strcspn(bmagic, " ");
943 return strcmp(amagic, bmagic) == 0;
945 #else
946 static inline int check_version(Elf_Shdr *sechdrs,
947 unsigned int versindex,
948 const char *symname,
949 struct module *mod,
950 const unsigned long *crc)
952 return 1;
955 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
956 unsigned int versindex,
957 struct module *mod)
959 return 1;
962 static inline int same_magic(const char *amagic, const char *bmagic)
964 return strcmp(amagic, bmagic) == 0;
966 #endif /* CONFIG_MODVERSIONS */
968 /* Resolve a symbol for this module. I.e. if we find one, record usage.
969 Must be holding module_mutex. */
970 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
971 unsigned int versindex,
972 const char *name,
973 struct module *mod)
975 struct module *owner;
976 unsigned long ret;
977 const unsigned long *crc;
979 ret = __find_symbol(name, &owner, &crc,
980 !(mod->taints & TAINT_PROPRIETARY_MODULE));
981 if (ret) {
982 /* use_module can fail due to OOM,
983 or module initialization or unloading */
984 if (!check_version(sechdrs, versindex, name, mod, crc) ||
985 !use_module(mod, owner))
986 ret = 0;
988 return ret;
993 * /sys/module/foo/sections stuff
994 * J. Corbet <corbet@lwn.net>
996 #ifdef CONFIG_KALLSYMS
997 static ssize_t module_sect_show(struct module_attribute *mattr,
998 struct module *mod, char *buf)
1000 struct module_sect_attr *sattr =
1001 container_of(mattr, struct module_sect_attr, mattr);
1002 return sprintf(buf, "0x%lx\n", sattr->address);
1005 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1007 int section;
1009 for (section = 0; section < sect_attrs->nsections; section++)
1010 kfree(sect_attrs->attrs[section].name);
1011 kfree(sect_attrs);
1014 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1015 char *secstrings, Elf_Shdr *sechdrs)
1017 unsigned int nloaded = 0, i, size[2];
1018 struct module_sect_attrs *sect_attrs;
1019 struct module_sect_attr *sattr;
1020 struct attribute **gattr;
1022 /* Count loaded sections and allocate structures */
1023 for (i = 0; i < nsect; i++)
1024 if (sechdrs[i].sh_flags & SHF_ALLOC)
1025 nloaded++;
1026 size[0] = ALIGN(sizeof(*sect_attrs)
1027 + nloaded * sizeof(sect_attrs->attrs[0]),
1028 sizeof(sect_attrs->grp.attrs[0]));
1029 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1030 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1031 if (sect_attrs == NULL)
1032 return;
1034 /* Setup section attributes. */
1035 sect_attrs->grp.name = "sections";
1036 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1038 sect_attrs->nsections = 0;
1039 sattr = &sect_attrs->attrs[0];
1040 gattr = &sect_attrs->grp.attrs[0];
1041 for (i = 0; i < nsect; i++) {
1042 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1043 continue;
1044 sattr->address = sechdrs[i].sh_addr;
1045 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1046 GFP_KERNEL);
1047 if (sattr->name == NULL)
1048 goto out;
1049 sect_attrs->nsections++;
1050 sattr->mattr.show = module_sect_show;
1051 sattr->mattr.store = NULL;
1052 sattr->mattr.attr.name = sattr->name;
1053 sattr->mattr.attr.mode = S_IRUGO;
1054 *(gattr++) = &(sattr++)->mattr.attr;
1056 *gattr = NULL;
1058 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1059 goto out;
1061 mod->sect_attrs = sect_attrs;
1062 return;
1063 out:
1064 free_sect_attrs(sect_attrs);
1067 static void remove_sect_attrs(struct module *mod)
1069 if (mod->sect_attrs) {
1070 sysfs_remove_group(&mod->mkobj.kobj,
1071 &mod->sect_attrs->grp);
1072 /* We are positive that no one is using any sect attrs
1073 * at this point. Deallocate immediately. */
1074 free_sect_attrs(mod->sect_attrs);
1075 mod->sect_attrs = NULL;
1080 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1083 struct module_notes_attrs {
1084 struct kobject *dir;
1085 unsigned int notes;
1086 struct bin_attribute attrs[0];
1089 static ssize_t module_notes_read(struct kobject *kobj,
1090 struct bin_attribute *bin_attr,
1091 char *buf, loff_t pos, size_t count)
1094 * The caller checked the pos and count against our size.
1096 memcpy(buf, bin_attr->private + pos, count);
1097 return count;
1100 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1101 unsigned int i)
1103 if (notes_attrs->dir) {
1104 while (i-- > 0)
1105 sysfs_remove_bin_file(notes_attrs->dir,
1106 &notes_attrs->attrs[i]);
1107 kobject_del(notes_attrs->dir);
1109 kfree(notes_attrs);
1112 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1113 char *secstrings, Elf_Shdr *sechdrs)
1115 unsigned int notes, loaded, i;
1116 struct module_notes_attrs *notes_attrs;
1117 struct bin_attribute *nattr;
1119 /* Count notes sections and allocate structures. */
1120 notes = 0;
1121 for (i = 0; i < nsect; i++)
1122 if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
1123 (sechdrs[i].sh_type == SHT_NOTE))
1124 ++notes;
1126 if (notes == 0)
1127 return;
1129 notes_attrs = kzalloc(sizeof(*notes_attrs)
1130 + notes * sizeof(notes_attrs->attrs[0]),
1131 GFP_KERNEL);
1132 if (notes_attrs == NULL)
1133 return;
1135 notes_attrs->notes = notes;
1136 nattr = &notes_attrs->attrs[0];
1137 for (loaded = i = 0; i < nsect; ++i) {
1138 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1139 continue;
1140 if (sechdrs[i].sh_type == SHT_NOTE) {
1141 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1142 nattr->attr.mode = S_IRUGO;
1143 nattr->size = sechdrs[i].sh_size;
1144 nattr->private = (void *) sechdrs[i].sh_addr;
1145 nattr->read = module_notes_read;
1146 ++nattr;
1148 ++loaded;
1151 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1152 if (!notes_attrs->dir)
1153 goto out;
1155 for (i = 0; i < notes; ++i)
1156 if (sysfs_create_bin_file(notes_attrs->dir,
1157 &notes_attrs->attrs[i]))
1158 goto out;
1160 mod->notes_attrs = notes_attrs;
1161 return;
1163 out:
1164 free_notes_attrs(notes_attrs, i);
1167 static void remove_notes_attrs(struct module *mod)
1169 if (mod->notes_attrs)
1170 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1173 #else
1175 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1176 char *sectstrings, Elf_Shdr *sechdrs)
1180 static inline void remove_sect_attrs(struct module *mod)
1184 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1185 char *sectstrings, Elf_Shdr *sechdrs)
1189 static inline void remove_notes_attrs(struct module *mod)
1192 #endif /* CONFIG_KALLSYMS */
1194 #ifdef CONFIG_SYSFS
1195 int module_add_modinfo_attrs(struct module *mod)
1197 struct module_attribute *attr;
1198 struct module_attribute *temp_attr;
1199 int error = 0;
1200 int i;
1202 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1203 (ARRAY_SIZE(modinfo_attrs) + 1)),
1204 GFP_KERNEL);
1205 if (!mod->modinfo_attrs)
1206 return -ENOMEM;
1208 temp_attr = mod->modinfo_attrs;
1209 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1210 if (!attr->test ||
1211 (attr->test && attr->test(mod))) {
1212 memcpy(temp_attr, attr, sizeof(*temp_attr));
1213 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1214 ++temp_attr;
1217 return error;
1220 void module_remove_modinfo_attrs(struct module *mod)
1222 struct module_attribute *attr;
1223 int i;
1225 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1226 /* pick a field to test for end of list */
1227 if (!attr->attr.name)
1228 break;
1229 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1230 if (attr->free)
1231 attr->free(mod);
1233 kfree(mod->modinfo_attrs);
1235 #endif
1237 #ifdef CONFIG_SYSFS
1238 int mod_sysfs_init(struct module *mod)
1240 int err;
1241 struct kobject *kobj;
1243 if (!module_sysfs_initialized) {
1244 printk(KERN_ERR "%s: module sysfs not initialized\n",
1245 mod->name);
1246 err = -EINVAL;
1247 goto out;
1250 kobj = kset_find_obj(module_kset, mod->name);
1251 if (kobj) {
1252 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1253 kobject_put(kobj);
1254 err = -EINVAL;
1255 goto out;
1258 mod->mkobj.mod = mod;
1260 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1261 mod->mkobj.kobj.kset = module_kset;
1262 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1263 "%s", mod->name);
1264 if (err)
1265 kobject_put(&mod->mkobj.kobj);
1267 /* delay uevent until full sysfs population */
1268 out:
1269 return err;
1272 int mod_sysfs_setup(struct module *mod,
1273 struct kernel_param *kparam,
1274 unsigned int num_params)
1276 int err;
1278 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1279 if (!mod->holders_dir) {
1280 err = -ENOMEM;
1281 goto out_unreg;
1284 err = module_param_sysfs_setup(mod, kparam, num_params);
1285 if (err)
1286 goto out_unreg_holders;
1288 err = module_add_modinfo_attrs(mod);
1289 if (err)
1290 goto out_unreg_param;
1292 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1293 return 0;
1295 out_unreg_param:
1296 module_param_sysfs_remove(mod);
1297 out_unreg_holders:
1298 kobject_put(mod->holders_dir);
1299 out_unreg:
1300 kobject_put(&mod->mkobj.kobj);
1301 return err;
1303 #endif
1305 static void mod_kobject_remove(struct module *mod)
1307 module_remove_modinfo_attrs(mod);
1308 module_param_sysfs_remove(mod);
1309 kobject_put(mod->mkobj.drivers_dir);
1310 kobject_put(mod->holders_dir);
1311 kobject_put(&mod->mkobj.kobj);
1315 * link the module with the whole machine is stopped with interrupts off
1316 * - this defends against kallsyms not taking locks
1318 static int __link_module(void *_mod)
1320 struct module *mod = _mod;
1321 list_add(&mod->list, &modules);
1322 return 0;
1326 * unlink the module with the whole machine is stopped with interrupts off
1327 * - this defends against kallsyms not taking locks
1329 static int __unlink_module(void *_mod)
1331 struct module *mod = _mod;
1332 list_del(&mod->list);
1333 return 0;
1336 /* Free a module, remove from lists, etc (must hold module_mutex). */
1337 static void free_module(struct module *mod)
1339 /* Delete from various lists */
1340 stop_machine_run(__unlink_module, mod, NR_CPUS);
1341 remove_notes_attrs(mod);
1342 remove_sect_attrs(mod);
1343 mod_kobject_remove(mod);
1345 unwind_remove_table(mod->unwind_info, 0);
1347 /* Arch-specific cleanup. */
1348 module_arch_cleanup(mod);
1350 /* Module unload stuff */
1351 module_unload_free(mod);
1353 /* This may be NULL, but that's OK */
1354 module_free(mod, mod->module_init);
1355 kfree(mod->args);
1356 if (mod->percpu)
1357 percpu_modfree(mod->percpu);
1359 /* Free lock-classes: */
1360 lockdep_free_key_range(mod->module_core, mod->core_size);
1362 /* Finally, free the core (containing the module structure) */
1363 module_free(mod, mod->module_core);
1366 void *__symbol_get(const char *symbol)
1368 struct module *owner;
1369 unsigned long value;
1370 const unsigned long *crc;
1372 preempt_disable();
1373 value = __find_symbol(symbol, &owner, &crc, 1);
1374 if (value && strong_try_module_get(owner) != 0)
1375 value = 0;
1376 preempt_enable();
1378 return (void *)value;
1380 EXPORT_SYMBOL_GPL(__symbol_get);
1383 * Ensure that an exported symbol [global namespace] does not already exist
1384 * in the kernel or in some other module's exported symbol table.
1386 static int verify_export_symbols(struct module *mod)
1388 const char *name = NULL;
1389 unsigned long i, ret = 0;
1390 struct module *owner;
1391 const unsigned long *crc;
1393 for (i = 0; i < mod->num_syms; i++)
1394 if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) {
1395 name = mod->syms[i].name;
1396 ret = -ENOEXEC;
1397 goto dup;
1400 for (i = 0; i < mod->num_gpl_syms; i++)
1401 if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) {
1402 name = mod->gpl_syms[i].name;
1403 ret = -ENOEXEC;
1404 goto dup;
1407 dup:
1408 if (ret)
1409 printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
1410 mod->name, name, module_name(owner));
1412 return ret;
1415 /* Change all symbols so that st_value encodes the pointer directly. */
1416 static int simplify_symbols(Elf_Shdr *sechdrs,
1417 unsigned int symindex,
1418 const char *strtab,
1419 unsigned int versindex,
1420 unsigned int pcpuindex,
1421 struct module *mod)
1423 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1424 unsigned long secbase;
1425 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1426 int ret = 0;
1428 for (i = 1; i < n; i++) {
1429 switch (sym[i].st_shndx) {
1430 case SHN_COMMON:
1431 /* We compiled with -fno-common. These are not
1432 supposed to happen. */
1433 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1434 printk("%s: please compile with -fno-common\n",
1435 mod->name);
1436 ret = -ENOEXEC;
1437 break;
1439 case SHN_ABS:
1440 /* Don't need to do anything */
1441 DEBUGP("Absolute symbol: 0x%08lx\n",
1442 (long)sym[i].st_value);
1443 break;
1445 case SHN_UNDEF:
1446 sym[i].st_value
1447 = resolve_symbol(sechdrs, versindex,
1448 strtab + sym[i].st_name, mod);
1450 /* Ok if resolved. */
1451 if (sym[i].st_value != 0)
1452 break;
1453 /* Ok if weak. */
1454 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1455 break;
1457 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1458 mod->name, strtab + sym[i].st_name);
1459 ret = -ENOENT;
1460 break;
1462 default:
1463 /* Divert to percpu allocation if a percpu var. */
1464 if (sym[i].st_shndx == pcpuindex)
1465 secbase = (unsigned long)mod->percpu;
1466 else
1467 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1468 sym[i].st_value += secbase;
1469 break;
1473 return ret;
1476 /* Update size with this section: return offset. */
1477 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
1479 long ret;
1481 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1482 *size = ret + sechdr->sh_size;
1483 return ret;
1486 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1487 might -- code, read-only data, read-write data, small data. Tally
1488 sizes, and place the offsets into sh_entsize fields: high bit means it
1489 belongs in init. */
1490 static void layout_sections(struct module *mod,
1491 const Elf_Ehdr *hdr,
1492 Elf_Shdr *sechdrs,
1493 const char *secstrings)
1495 static unsigned long const masks[][2] = {
1496 /* NOTE: all executable code must be the first section
1497 * in this array; otherwise modify the text_size
1498 * finder in the two loops below */
1499 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1500 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1501 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1502 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1504 unsigned int m, i;
1506 for (i = 0; i < hdr->e_shnum; i++)
1507 sechdrs[i].sh_entsize = ~0UL;
1509 DEBUGP("Core section allocation order:\n");
1510 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1511 for (i = 0; i < hdr->e_shnum; ++i) {
1512 Elf_Shdr *s = &sechdrs[i];
1514 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1515 || (s->sh_flags & masks[m][1])
1516 || s->sh_entsize != ~0UL
1517 || strncmp(secstrings + s->sh_name,
1518 ".init", 5) == 0)
1519 continue;
1520 s->sh_entsize = get_offset(&mod->core_size, s);
1521 DEBUGP("\t%s\n", secstrings + s->sh_name);
1523 if (m == 0)
1524 mod->core_text_size = mod->core_size;
1527 DEBUGP("Init section allocation order:\n");
1528 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1529 for (i = 0; i < hdr->e_shnum; ++i) {
1530 Elf_Shdr *s = &sechdrs[i];
1532 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1533 || (s->sh_flags & masks[m][1])
1534 || s->sh_entsize != ~0UL
1535 || strncmp(secstrings + s->sh_name,
1536 ".init", 5) != 0)
1537 continue;
1538 s->sh_entsize = (get_offset(&mod->init_size, s)
1539 | INIT_OFFSET_MASK);
1540 DEBUGP("\t%s\n", secstrings + s->sh_name);
1542 if (m == 0)
1543 mod->init_text_size = mod->init_size;
1547 static void set_license(struct module *mod, const char *license)
1549 if (!license)
1550 license = "unspecified";
1552 if (!license_is_gpl_compatible(license)) {
1553 if (!(tainted & TAINT_PROPRIETARY_MODULE))
1554 printk(KERN_WARNING "%s: module license '%s' taints "
1555 "kernel.\n", mod->name, license);
1556 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1560 /* Parse tag=value strings from .modinfo section */
1561 static char *next_string(char *string, unsigned long *secsize)
1563 /* Skip non-zero chars */
1564 while (string[0]) {
1565 string++;
1566 if ((*secsize)-- <= 1)
1567 return NULL;
1570 /* Skip any zero padding. */
1571 while (!string[0]) {
1572 string++;
1573 if ((*secsize)-- <= 1)
1574 return NULL;
1576 return string;
1579 static char *get_modinfo(Elf_Shdr *sechdrs,
1580 unsigned int info,
1581 const char *tag)
1583 char *p;
1584 unsigned int taglen = strlen(tag);
1585 unsigned long size = sechdrs[info].sh_size;
1587 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1588 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1589 return p + taglen + 1;
1591 return NULL;
1594 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1595 unsigned int infoindex)
1597 struct module_attribute *attr;
1598 int i;
1600 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1601 if (attr->setup)
1602 attr->setup(mod,
1603 get_modinfo(sechdrs,
1604 infoindex,
1605 attr->attr.name));
1609 #ifdef CONFIG_KALLSYMS
1610 static int is_exported(const char *name, const struct module *mod)
1612 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1613 return 1;
1614 else
1615 if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1616 return 1;
1617 else
1618 return 0;
1621 /* As per nm */
1622 static char elf_type(const Elf_Sym *sym,
1623 Elf_Shdr *sechdrs,
1624 const char *secstrings,
1625 struct module *mod)
1627 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1628 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1629 return 'v';
1630 else
1631 return 'w';
1633 if (sym->st_shndx == SHN_UNDEF)
1634 return 'U';
1635 if (sym->st_shndx == SHN_ABS)
1636 return 'a';
1637 if (sym->st_shndx >= SHN_LORESERVE)
1638 return '?';
1639 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1640 return 't';
1641 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1642 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1643 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1644 return 'r';
1645 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1646 return 'g';
1647 else
1648 return 'd';
1650 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1651 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1652 return 's';
1653 else
1654 return 'b';
1656 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1657 ".debug", strlen(".debug")) == 0)
1658 return 'n';
1659 return '?';
1662 static void add_kallsyms(struct module *mod,
1663 Elf_Shdr *sechdrs,
1664 unsigned int symindex,
1665 unsigned int strindex,
1666 const char *secstrings)
1668 unsigned int i;
1670 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1671 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1672 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1674 /* Set types up while we still have access to sections. */
1675 for (i = 0; i < mod->num_symtab; i++)
1676 mod->symtab[i].st_info
1677 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1679 #else
1680 static inline void add_kallsyms(struct module *mod,
1681 Elf_Shdr *sechdrs,
1682 unsigned int symindex,
1683 unsigned int strindex,
1684 const char *secstrings)
1687 #endif /* CONFIG_KALLSYMS */
1689 /* Allocate and load the module: note that size of section 0 is always
1690 zero, and we rely on this for optional sections. */
1691 static struct module *load_module(void __user *umod,
1692 unsigned long len,
1693 const char __user *uargs)
1695 Elf_Ehdr *hdr;
1696 Elf_Shdr *sechdrs;
1697 char *secstrings, *args, *modmagic, *strtab = NULL;
1698 unsigned int i;
1699 unsigned int symindex = 0;
1700 unsigned int strindex = 0;
1701 unsigned int setupindex;
1702 unsigned int exindex;
1703 unsigned int exportindex;
1704 unsigned int modindex;
1705 unsigned int obsparmindex;
1706 unsigned int infoindex;
1707 unsigned int gplindex;
1708 unsigned int crcindex;
1709 unsigned int gplcrcindex;
1710 unsigned int versindex;
1711 unsigned int pcpuindex;
1712 unsigned int gplfutureindex;
1713 unsigned int gplfuturecrcindex;
1714 unsigned int unwindex = 0;
1715 unsigned int unusedindex;
1716 unsigned int unusedcrcindex;
1717 unsigned int unusedgplindex;
1718 unsigned int unusedgplcrcindex;
1719 unsigned int markersindex;
1720 unsigned int markersstringsindex;
1721 struct module *mod;
1722 long err = 0;
1723 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1724 struct exception_table_entry *extable;
1725 mm_segment_t old_fs;
1727 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1728 umod, len, uargs);
1729 if (len < sizeof(*hdr))
1730 return ERR_PTR(-ENOEXEC);
1732 /* Suck in entire file: we'll want most of it. */
1733 /* vmalloc barfs on "unusual" numbers. Check here */
1734 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1735 return ERR_PTR(-ENOMEM);
1736 if (copy_from_user(hdr, umod, len) != 0) {
1737 err = -EFAULT;
1738 goto free_hdr;
1741 /* Sanity checks against insmoding binaries or wrong arch,
1742 weird elf version */
1743 if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
1744 || hdr->e_type != ET_REL
1745 || !elf_check_arch(hdr)
1746 || hdr->e_shentsize != sizeof(*sechdrs)) {
1747 err = -ENOEXEC;
1748 goto free_hdr;
1751 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1752 goto truncated;
1754 /* Convenience variables */
1755 sechdrs = (void *)hdr + hdr->e_shoff;
1756 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1757 sechdrs[0].sh_addr = 0;
1759 for (i = 1; i < hdr->e_shnum; i++) {
1760 if (sechdrs[i].sh_type != SHT_NOBITS
1761 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1762 goto truncated;
1764 /* Mark all sections sh_addr with their address in the
1765 temporary image. */
1766 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1768 /* Internal symbols and strings. */
1769 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1770 symindex = i;
1771 strindex = sechdrs[i].sh_link;
1772 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1774 #ifndef CONFIG_MODULE_UNLOAD
1775 /* Don't load .exit sections */
1776 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1777 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1778 #endif
1781 modindex = find_sec(hdr, sechdrs, secstrings,
1782 ".gnu.linkonce.this_module");
1783 if (!modindex) {
1784 printk(KERN_WARNING "No module found in object\n");
1785 err = -ENOEXEC;
1786 goto free_hdr;
1788 mod = (void *)sechdrs[modindex].sh_addr;
1790 if (symindex == 0) {
1791 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1792 mod->name);
1793 err = -ENOEXEC;
1794 goto free_hdr;
1797 /* Optional sections */
1798 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1799 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1800 gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1801 unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
1802 unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
1803 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1804 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1805 gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1806 unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
1807 unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
1808 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1809 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1810 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1811 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1812 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1813 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1814 #ifdef ARCH_UNWIND_SECTION_NAME
1815 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1816 #endif
1818 /* Don't keep modinfo section */
1819 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1820 #ifdef CONFIG_KALLSYMS
1821 /* Keep symbol and string tables for decoding later. */
1822 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1823 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1824 #endif
1825 if (unwindex)
1826 sechdrs[unwindex].sh_flags |= SHF_ALLOC;
1828 /* Check module struct version now, before we try to use module. */
1829 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1830 err = -ENOEXEC;
1831 goto free_hdr;
1834 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1835 /* This is allowed: modprobe --force will invalidate it. */
1836 if (!modmagic) {
1837 add_taint_module(mod, TAINT_FORCED_MODULE);
1838 printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
1839 mod->name);
1840 } else if (!same_magic(modmagic, vermagic)) {
1841 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1842 mod->name, modmagic, vermagic);
1843 err = -ENOEXEC;
1844 goto free_hdr;
1847 /* Now copy in args */
1848 args = strndup_user(uargs, ~0UL >> 1);
1849 if (IS_ERR(args)) {
1850 err = PTR_ERR(args);
1851 goto free_hdr;
1854 if (find_module(mod->name)) {
1855 err = -EEXIST;
1856 goto free_mod;
1859 mod->state = MODULE_STATE_COMING;
1861 /* Allow arches to frob section contents and sizes. */
1862 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1863 if (err < 0)
1864 goto free_mod;
1866 if (pcpuindex) {
1867 /* We have a special allocation for this section. */
1868 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1869 sechdrs[pcpuindex].sh_addralign,
1870 mod->name);
1871 if (!percpu) {
1872 err = -ENOMEM;
1873 goto free_mod;
1875 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1876 mod->percpu = percpu;
1879 /* Determine total sizes, and put offsets in sh_entsize. For now
1880 this is done generically; there doesn't appear to be any
1881 special cases for the architectures. */
1882 layout_sections(mod, hdr, sechdrs, secstrings);
1884 /* Do the allocs. */
1885 ptr = module_alloc(mod->core_size);
1886 if (!ptr) {
1887 err = -ENOMEM;
1888 goto free_percpu;
1890 memset(ptr, 0, mod->core_size);
1891 mod->module_core = ptr;
1893 ptr = module_alloc(mod->init_size);
1894 if (!ptr && mod->init_size) {
1895 err = -ENOMEM;
1896 goto free_core;
1898 memset(ptr, 0, mod->init_size);
1899 mod->module_init = ptr;
1901 /* Transfer each section which specifies SHF_ALLOC */
1902 DEBUGP("final section addresses:\n");
1903 for (i = 0; i < hdr->e_shnum; i++) {
1904 void *dest;
1906 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1907 continue;
1909 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
1910 dest = mod->module_init
1911 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
1912 else
1913 dest = mod->module_core + sechdrs[i].sh_entsize;
1915 if (sechdrs[i].sh_type != SHT_NOBITS)
1916 memcpy(dest, (void *)sechdrs[i].sh_addr,
1917 sechdrs[i].sh_size);
1918 /* Update sh_addr to point to copy in image. */
1919 sechdrs[i].sh_addr = (unsigned long)dest;
1920 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
1922 /* Module has been moved. */
1923 mod = (void *)sechdrs[modindex].sh_addr;
1925 /* Now we've moved module, initialize linked lists, etc. */
1926 module_unload_init(mod);
1928 /* add kobject, so we can reference it. */
1929 err = mod_sysfs_init(mod);
1930 if (err)
1931 goto free_unload;
1933 /* Set up license info based on the info section */
1934 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
1936 if (strcmp(mod->name, "ndiswrapper") == 0)
1937 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1938 if (strcmp(mod->name, "driverloader") == 0)
1939 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1941 /* Set up MODINFO_ATTR fields */
1942 setup_modinfo(mod, sechdrs, infoindex);
1944 /* Fix up syms, so that st_value is a pointer to location. */
1945 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
1946 mod);
1947 if (err < 0)
1948 goto cleanup;
1950 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
1951 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
1952 mod->syms = (void *)sechdrs[exportindex].sh_addr;
1953 if (crcindex)
1954 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
1955 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
1956 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
1957 if (gplcrcindex)
1958 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
1959 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
1960 sizeof(*mod->gpl_future_syms);
1961 mod->num_unused_syms = sechdrs[unusedindex].sh_size /
1962 sizeof(*mod->unused_syms);
1963 mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
1964 sizeof(*mod->unused_gpl_syms);
1965 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
1966 if (gplfuturecrcindex)
1967 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
1969 mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
1970 if (unusedcrcindex)
1971 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
1972 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
1973 if (unusedgplcrcindex)
1974 mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr;
1976 #ifdef CONFIG_MODVERSIONS
1977 if ((mod->num_syms && !crcindex) ||
1978 (mod->num_gpl_syms && !gplcrcindex) ||
1979 (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
1980 (mod->num_unused_syms && !unusedcrcindex) ||
1981 (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
1982 printk(KERN_WARNING "%s: No versions for exported symbols."
1983 " Tainting kernel.\n", mod->name);
1984 add_taint_module(mod, TAINT_FORCED_MODULE);
1986 #endif
1987 markersindex = find_sec(hdr, sechdrs, secstrings, "__markers");
1988 markersstringsindex = find_sec(hdr, sechdrs, secstrings,
1989 "__markers_strings");
1991 /* Now do relocations. */
1992 for (i = 1; i < hdr->e_shnum; i++) {
1993 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1994 unsigned int info = sechdrs[i].sh_info;
1996 /* Not a valid relocation section? */
1997 if (info >= hdr->e_shnum)
1998 continue;
2000 /* Don't bother with non-allocated sections */
2001 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2002 continue;
2004 if (sechdrs[i].sh_type == SHT_REL)
2005 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2006 else if (sechdrs[i].sh_type == SHT_RELA)
2007 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2008 mod);
2009 if (err < 0)
2010 goto cleanup;
2012 #ifdef CONFIG_MARKERS
2013 mod->markers = (void *)sechdrs[markersindex].sh_addr;
2014 mod->num_markers =
2015 sechdrs[markersindex].sh_size / sizeof(*mod->markers);
2016 #endif
2018 /* Find duplicate symbols */
2019 err = verify_export_symbols(mod);
2021 if (err < 0)
2022 goto cleanup;
2024 /* Set up and sort exception table */
2025 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
2026 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
2027 sort_extable(extable, extable + mod->num_exentries);
2029 /* Finally, copy percpu area over. */
2030 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
2031 sechdrs[pcpuindex].sh_size);
2033 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
2035 #ifdef CONFIG_MARKERS
2036 if (!mod->taints)
2037 marker_update_probe_range(mod->markers,
2038 mod->markers + mod->num_markers, NULL, NULL);
2039 #endif
2040 err = module_finalize(hdr, sechdrs, mod);
2041 if (err < 0)
2042 goto cleanup;
2044 /* flush the icache in correct context */
2045 old_fs = get_fs();
2046 set_fs(KERNEL_DS);
2049 * Flush the instruction cache, since we've played with text.
2050 * Do it before processing of module parameters, so the module
2051 * can provide parameter accessor functions of its own.
2053 if (mod->module_init)
2054 flush_icache_range((unsigned long)mod->module_init,
2055 (unsigned long)mod->module_init
2056 + mod->init_size);
2057 flush_icache_range((unsigned long)mod->module_core,
2058 (unsigned long)mod->module_core + mod->core_size);
2060 set_fs(old_fs);
2062 mod->args = args;
2063 if (obsparmindex)
2064 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2065 mod->name);
2067 /* Now sew it into the lists so we can get lockdep and oops
2068 * info during argument parsing. Noone should access us, since
2069 * strong_try_module_get() will fail. */
2070 stop_machine_run(__link_module, mod, NR_CPUS);
2072 /* Size of section 0 is 0, so this works well if no params */
2073 err = parse_args(mod->name, mod->args,
2074 (struct kernel_param *)
2075 sechdrs[setupindex].sh_addr,
2076 sechdrs[setupindex].sh_size
2077 / sizeof(struct kernel_param),
2078 NULL);
2079 if (err < 0)
2080 goto unlink;
2082 err = mod_sysfs_setup(mod,
2083 (struct kernel_param *)
2084 sechdrs[setupindex].sh_addr,
2085 sechdrs[setupindex].sh_size
2086 / sizeof(struct kernel_param));
2087 if (err < 0)
2088 goto unlink;
2089 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2090 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2092 /* Size of section 0 is 0, so this works well if no unwind info. */
2093 mod->unwind_info = unwind_add_table(mod,
2094 (void *)sechdrs[unwindex].sh_addr,
2095 sechdrs[unwindex].sh_size);
2097 /* Get rid of temporary copy */
2098 vfree(hdr);
2100 /* Done! */
2101 return mod;
2103 unlink:
2104 stop_machine_run(__unlink_module, mod, NR_CPUS);
2105 module_arch_cleanup(mod);
2106 cleanup:
2107 kobject_del(&mod->mkobj.kobj);
2108 kobject_put(&mod->mkobj.kobj);
2109 free_unload:
2110 module_unload_free(mod);
2111 module_free(mod, mod->module_init);
2112 free_core:
2113 module_free(mod, mod->module_core);
2114 free_percpu:
2115 if (percpu)
2116 percpu_modfree(percpu);
2117 free_mod:
2118 kfree(args);
2119 free_hdr:
2120 vfree(hdr);
2121 return ERR_PTR(err);
2123 truncated:
2124 printk(KERN_ERR "Module len %lu truncated\n", len);
2125 err = -ENOEXEC;
2126 goto free_hdr;
2129 /* This is where the real work happens */
2130 asmlinkage long
2131 sys_init_module(void __user *umod,
2132 unsigned long len,
2133 const char __user *uargs)
2135 struct module *mod;
2136 int ret = 0;
2138 /* Must have permission */
2139 if (!capable(CAP_SYS_MODULE))
2140 return -EPERM;
2142 /* Only one module load at a time, please */
2143 if (mutex_lock_interruptible(&module_mutex) != 0)
2144 return -EINTR;
2146 /* Do all the hard work */
2147 mod = load_module(umod, len, uargs);
2148 if (IS_ERR(mod)) {
2149 mutex_unlock(&module_mutex);
2150 return PTR_ERR(mod);
2153 /* Drop lock so they can recurse */
2154 mutex_unlock(&module_mutex);
2156 blocking_notifier_call_chain(&module_notify_list,
2157 MODULE_STATE_COMING, mod);
2159 /* Start the module */
2160 if (mod->init != NULL)
2161 ret = mod->init();
2162 if (ret < 0) {
2163 /* Init routine failed: abort. Try to protect us from
2164 buggy refcounters. */
2165 mod->state = MODULE_STATE_GOING;
2166 synchronize_sched();
2167 module_put(mod);
2168 mutex_lock(&module_mutex);
2169 free_module(mod);
2170 mutex_unlock(&module_mutex);
2171 wake_up(&module_wq);
2172 return ret;
2175 /* Now it's a first class citizen! */
2176 mutex_lock(&module_mutex);
2177 mod->state = MODULE_STATE_LIVE;
2178 /* Drop initial reference. */
2179 module_put(mod);
2180 unwind_remove_table(mod->unwind_info, 1);
2181 module_free(mod, mod->module_init);
2182 mod->module_init = NULL;
2183 mod->init_size = 0;
2184 mod->init_text_size = 0;
2185 mutex_unlock(&module_mutex);
2186 wake_up(&module_wq);
2188 return 0;
2191 static inline int within(unsigned long addr, void *start, unsigned long size)
2193 return ((void *)addr >= start && (void *)addr < start + size);
2196 #ifdef CONFIG_KALLSYMS
2198 * This ignores the intensely annoying "mapping symbols" found
2199 * in ARM ELF files: $a, $t and $d.
2201 static inline int is_arm_mapping_symbol(const char *str)
2203 return str[0] == '$' && strchr("atd", str[1])
2204 && (str[2] == '\0' || str[2] == '.');
2207 static const char *get_ksymbol(struct module *mod,
2208 unsigned long addr,
2209 unsigned long *size,
2210 unsigned long *offset)
2212 unsigned int i, best = 0;
2213 unsigned long nextval;
2215 /* At worse, next value is at end of module */
2216 if (within(addr, mod->module_init, mod->init_size))
2217 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2218 else
2219 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2221 /* Scan for closest preceeding symbol, and next symbol. (ELF
2222 starts real symbols at 1). */
2223 for (i = 1; i < mod->num_symtab; i++) {
2224 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2225 continue;
2227 /* We ignore unnamed symbols: they're uninformative
2228 * and inserted at a whim. */
2229 if (mod->symtab[i].st_value <= addr
2230 && mod->symtab[i].st_value > mod->symtab[best].st_value
2231 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2232 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2233 best = i;
2234 if (mod->symtab[i].st_value > addr
2235 && mod->symtab[i].st_value < nextval
2236 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2237 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2238 nextval = mod->symtab[i].st_value;
2241 if (!best)
2242 return NULL;
2244 if (size)
2245 *size = nextval - mod->symtab[best].st_value;
2246 if (offset)
2247 *offset = addr - mod->symtab[best].st_value;
2248 return mod->strtab + mod->symtab[best].st_name;
2251 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2252 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2253 char *module_address_lookup(unsigned long addr,
2254 unsigned long *size,
2255 unsigned long *offset,
2256 char **modname,
2257 char *namebuf)
2259 struct module *mod;
2260 const char *ret = NULL;
2262 preempt_disable();
2263 list_for_each_entry(mod, &modules, list) {
2264 if (within(addr, mod->module_init, mod->init_size)
2265 || within(addr, mod->module_core, mod->core_size)) {
2266 if (modname)
2267 *modname = mod->name;
2268 ret = get_ksymbol(mod, addr, size, offset);
2269 break;
2272 /* Make a copy in here where it's safe */
2273 if (ret) {
2274 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2275 ret = namebuf;
2277 preempt_enable();
2278 return (char *)ret;
2281 int lookup_module_symbol_name(unsigned long addr, char *symname)
2283 struct module *mod;
2285 preempt_disable();
2286 list_for_each_entry(mod, &modules, list) {
2287 if (within(addr, mod->module_init, mod->init_size) ||
2288 within(addr, mod->module_core, mod->core_size)) {
2289 const char *sym;
2291 sym = get_ksymbol(mod, addr, NULL, NULL);
2292 if (!sym)
2293 goto out;
2294 strlcpy(symname, sym, KSYM_NAME_LEN);
2295 preempt_enable();
2296 return 0;
2299 out:
2300 preempt_enable();
2301 return -ERANGE;
2304 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2305 unsigned long *offset, char *modname, char *name)
2307 struct module *mod;
2309 preempt_disable();
2310 list_for_each_entry(mod, &modules, list) {
2311 if (within(addr, mod->module_init, mod->init_size) ||
2312 within(addr, mod->module_core, mod->core_size)) {
2313 const char *sym;
2315 sym = get_ksymbol(mod, addr, size, offset);
2316 if (!sym)
2317 goto out;
2318 if (modname)
2319 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2320 if (name)
2321 strlcpy(name, sym, KSYM_NAME_LEN);
2322 preempt_enable();
2323 return 0;
2326 out:
2327 preempt_enable();
2328 return -ERANGE;
2331 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2332 char *name, char *module_name, int *exported)
2334 struct module *mod;
2336 preempt_disable();
2337 list_for_each_entry(mod, &modules, list) {
2338 if (symnum < mod->num_symtab) {
2339 *value = mod->symtab[symnum].st_value;
2340 *type = mod->symtab[symnum].st_info;
2341 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2342 KSYM_NAME_LEN);
2343 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2344 *exported = is_exported(name, mod);
2345 preempt_enable();
2346 return 0;
2348 symnum -= mod->num_symtab;
2350 preempt_enable();
2351 return -ERANGE;
2354 static unsigned long mod_find_symname(struct module *mod, const char *name)
2356 unsigned int i;
2358 for (i = 0; i < mod->num_symtab; i++)
2359 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2360 mod->symtab[i].st_info != 'U')
2361 return mod->symtab[i].st_value;
2362 return 0;
2365 /* Look for this name: can be of form module:name. */
2366 unsigned long module_kallsyms_lookup_name(const char *name)
2368 struct module *mod;
2369 char *colon;
2370 unsigned long ret = 0;
2372 /* Don't lock: we're in enough trouble already. */
2373 preempt_disable();
2374 if ((colon = strchr(name, ':')) != NULL) {
2375 *colon = '\0';
2376 if ((mod = find_module(name)) != NULL)
2377 ret = mod_find_symname(mod, colon+1);
2378 *colon = ':';
2379 } else {
2380 list_for_each_entry(mod, &modules, list)
2381 if ((ret = mod_find_symname(mod, name)) != 0)
2382 break;
2384 preempt_enable();
2385 return ret;
2387 #endif /* CONFIG_KALLSYMS */
2389 /* Called by the /proc file system to return a list of modules. */
2390 static void *m_start(struct seq_file *m, loff_t *pos)
2392 mutex_lock(&module_mutex);
2393 return seq_list_start(&modules, *pos);
2396 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2398 return seq_list_next(p, &modules, pos);
2401 static void m_stop(struct seq_file *m, void *p)
2403 mutex_unlock(&module_mutex);
2406 static char *module_flags(struct module *mod, char *buf)
2408 int bx = 0;
2410 if (mod->taints ||
2411 mod->state == MODULE_STATE_GOING ||
2412 mod->state == MODULE_STATE_COMING) {
2413 buf[bx++] = '(';
2414 if (mod->taints & TAINT_PROPRIETARY_MODULE)
2415 buf[bx++] = 'P';
2416 if (mod->taints & TAINT_FORCED_MODULE)
2417 buf[bx++] = 'F';
2419 * TAINT_FORCED_RMMOD: could be added.
2420 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2421 * apply to modules.
2424 /* Show a - for module-is-being-unloaded */
2425 if (mod->state == MODULE_STATE_GOING)
2426 buf[bx++] = '-';
2427 /* Show a + for module-is-being-loaded */
2428 if (mod->state == MODULE_STATE_COMING)
2429 buf[bx++] = '+';
2430 buf[bx++] = ')';
2432 buf[bx] = '\0';
2434 return buf;
2437 static int m_show(struct seq_file *m, void *p)
2439 struct module *mod = list_entry(p, struct module, list);
2440 char buf[8];
2442 seq_printf(m, "%s %lu",
2443 mod->name, mod->init_size + mod->core_size);
2444 print_unload_info(m, mod);
2446 /* Informative for users. */
2447 seq_printf(m, " %s",
2448 mod->state == MODULE_STATE_GOING ? "Unloading":
2449 mod->state == MODULE_STATE_COMING ? "Loading":
2450 "Live");
2451 /* Used by oprofile and other similar tools. */
2452 seq_printf(m, " 0x%p", mod->module_core);
2454 /* Taints info */
2455 if (mod->taints)
2456 seq_printf(m, " %s", module_flags(mod, buf));
2458 seq_printf(m, "\n");
2459 return 0;
2462 /* Format: modulename size refcount deps address
2464 Where refcount is a number or -, and deps is a comma-separated list
2465 of depends or -.
2467 const struct seq_operations modules_op = {
2468 .start = m_start,
2469 .next = m_next,
2470 .stop = m_stop,
2471 .show = m_show
2474 /* Given an address, look for it in the module exception tables. */
2475 const struct exception_table_entry *search_module_extables(unsigned long addr)
2477 const struct exception_table_entry *e = NULL;
2478 struct module *mod;
2480 preempt_disable();
2481 list_for_each_entry(mod, &modules, list) {
2482 if (mod->num_exentries == 0)
2483 continue;
2485 e = search_extable(mod->extable,
2486 mod->extable + mod->num_exentries - 1,
2487 addr);
2488 if (e)
2489 break;
2491 preempt_enable();
2493 /* Now, if we found one, we are running inside it now, hence
2494 we cannot unload the module, hence no refcnt needed. */
2495 return e;
2499 * Is this a valid module address?
2501 int is_module_address(unsigned long addr)
2503 struct module *mod;
2505 preempt_disable();
2507 list_for_each_entry(mod, &modules, list) {
2508 if (within(addr, mod->module_core, mod->core_size)) {
2509 preempt_enable();
2510 return 1;
2514 preempt_enable();
2516 return 0;
2520 /* Is this a valid kernel address? */
2521 struct module *__module_text_address(unsigned long addr)
2523 struct module *mod;
2525 list_for_each_entry(mod, &modules, list)
2526 if (within(addr, mod->module_init, mod->init_text_size)
2527 || within(addr, mod->module_core, mod->core_text_size))
2528 return mod;
2529 return NULL;
2532 struct module *module_text_address(unsigned long addr)
2534 struct module *mod;
2536 preempt_disable();
2537 mod = __module_text_address(addr);
2538 preempt_enable();
2540 return mod;
2543 /* Don't grab lock, we're oopsing. */
2544 void print_modules(void)
2546 struct module *mod;
2547 char buf[8];
2549 printk("Modules linked in:");
2550 list_for_each_entry(mod, &modules, list)
2551 printk(" %s%s", mod->name, module_flags(mod, buf));
2552 if (last_unloaded_module[0])
2553 printk(" [last unloaded: %s]", last_unloaded_module);
2554 printk("\n");
2557 #ifdef CONFIG_MODVERSIONS
2558 /* Generate the signature for struct module here, too, for modversions. */
2559 void struct_module(struct module *mod) { return; }
2560 EXPORT_SYMBOL(struct_module);
2561 #endif
2563 #ifdef CONFIG_MARKERS
2564 void module_update_markers(struct module *probe_module, int *refcount)
2566 struct module *mod;
2568 mutex_lock(&module_mutex);
2569 list_for_each_entry(mod, &modules, list)
2570 if (!mod->taints)
2571 marker_update_probe_range(mod->markers,
2572 mod->markers + mod->num_markers,
2573 probe_module, refcount);
2574 mutex_unlock(&module_mutex);
2576 #endif