Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6
[wrt350n-kernel.git] / kernel / module.c
blobbe4807fb90e48afd4ec74c460aaf8a214c4b0a4a
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>
49 #include <asm/sections.h>
51 #if 0
52 #define DEBUGP printk
53 #else
54 #define DEBUGP(fmt , a...)
55 #endif
57 #ifndef ARCH_SHF_SMALL
58 #define ARCH_SHF_SMALL 0
59 #endif
61 /* If this is set, the section belongs in the init part of the module */
62 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
64 /* List of modules, protected by module_mutex or preempt_disable
65 * (add/delete uses stop_machine). */
66 static DEFINE_MUTEX(module_mutex);
67 static LIST_HEAD(modules);
69 /* Waiting for a module to finish initializing? */
70 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
72 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
74 int register_module_notifier(struct notifier_block * nb)
76 return blocking_notifier_chain_register(&module_notify_list, nb);
78 EXPORT_SYMBOL(register_module_notifier);
80 int unregister_module_notifier(struct notifier_block * nb)
82 return blocking_notifier_chain_unregister(&module_notify_list, nb);
84 EXPORT_SYMBOL(unregister_module_notifier);
86 /* We require a truly strong try_module_get(): 0 means failure due to
87 ongoing or failed initialization etc. */
88 static inline int strong_try_module_get(struct module *mod)
90 if (mod && mod->state == MODULE_STATE_COMING)
91 return -EBUSY;
92 if (try_module_get(mod))
93 return 0;
94 else
95 return -ENOENT;
98 static inline void add_taint_module(struct module *mod, unsigned flag)
100 add_taint(flag);
101 mod->taints |= flag;
105 * A thread that wants to hold a reference to a module only while it
106 * is running can call this to safely exit. nfsd and lockd use this.
108 void __module_put_and_exit(struct module *mod, long code)
110 module_put(mod);
111 do_exit(code);
113 EXPORT_SYMBOL(__module_put_and_exit);
115 /* Find a module section: 0 means not found. */
116 static unsigned int find_sec(Elf_Ehdr *hdr,
117 Elf_Shdr *sechdrs,
118 const char *secstrings,
119 const char *name)
121 unsigned int i;
123 for (i = 1; i < hdr->e_shnum; i++)
124 /* Alloc bit cleared means "ignore it." */
125 if ((sechdrs[i].sh_flags & SHF_ALLOC)
126 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
127 return i;
128 return 0;
131 /* Provided by the linker */
132 extern const struct kernel_symbol __start___ksymtab[];
133 extern const struct kernel_symbol __stop___ksymtab[];
134 extern const struct kernel_symbol __start___ksymtab_gpl[];
135 extern const struct kernel_symbol __stop___ksymtab_gpl[];
136 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
137 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
138 extern const struct kernel_symbol __start___ksymtab_unused[];
139 extern const struct kernel_symbol __stop___ksymtab_unused[];
140 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
141 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
142 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
143 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
144 extern const unsigned long __start___kcrctab[];
145 extern const unsigned long __start___kcrctab_gpl[];
146 extern const unsigned long __start___kcrctab_gpl_future[];
147 extern const unsigned long __start___kcrctab_unused[];
148 extern const unsigned long __start___kcrctab_unused_gpl[];
150 #ifndef CONFIG_MODVERSIONS
151 #define symversion(base, idx) NULL
152 #else
153 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
154 #endif
156 /* lookup symbol in given range of kernel_symbols */
157 static const struct kernel_symbol *lookup_symbol(const char *name,
158 const struct kernel_symbol *start,
159 const struct kernel_symbol *stop)
161 const struct kernel_symbol *ks = start;
162 for (; ks < stop; ks++)
163 if (strcmp(ks->name, name) == 0)
164 return ks;
165 return NULL;
168 static void printk_unused_warning(const char *name)
170 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
171 "however this module is using it.\n", name);
172 printk(KERN_WARNING "This symbol will go away in the future.\n");
173 printk(KERN_WARNING "Please evalute if this is the right api to use, "
174 "and if it really is, submit a report the linux kernel "
175 "mailinglist together with submitting your code for "
176 "inclusion.\n");
179 /* Find a symbol, return value, crc and module which owns it */
180 static unsigned long __find_symbol(const char *name,
181 struct module **owner,
182 const unsigned long **crc,
183 int gplok)
185 struct module *mod;
186 const struct kernel_symbol *ks;
188 /* Core kernel first. */
189 *owner = NULL;
190 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
191 if (ks) {
192 *crc = symversion(__start___kcrctab, (ks - __start___ksymtab));
193 return ks->value;
195 if (gplok) {
196 ks = lookup_symbol(name, __start___ksymtab_gpl,
197 __stop___ksymtab_gpl);
198 if (ks) {
199 *crc = symversion(__start___kcrctab_gpl,
200 (ks - __start___ksymtab_gpl));
201 return ks->value;
204 ks = lookup_symbol(name, __start___ksymtab_gpl_future,
205 __stop___ksymtab_gpl_future);
206 if (ks) {
207 if (!gplok) {
208 printk(KERN_WARNING "Symbol %s is being used "
209 "by a non-GPL module, which will not "
210 "be allowed in the future\n", name);
211 printk(KERN_WARNING "Please see the file "
212 "Documentation/feature-removal-schedule.txt "
213 "in the kernel source tree for more "
214 "details.\n");
216 *crc = symversion(__start___kcrctab_gpl_future,
217 (ks - __start___ksymtab_gpl_future));
218 return ks->value;
221 ks = lookup_symbol(name, __start___ksymtab_unused,
222 __stop___ksymtab_unused);
223 if (ks) {
224 printk_unused_warning(name);
225 *crc = symversion(__start___kcrctab_unused,
226 (ks - __start___ksymtab_unused));
227 return ks->value;
230 if (gplok)
231 ks = lookup_symbol(name, __start___ksymtab_unused_gpl,
232 __stop___ksymtab_unused_gpl);
233 if (ks) {
234 printk_unused_warning(name);
235 *crc = symversion(__start___kcrctab_unused_gpl,
236 (ks - __start___ksymtab_unused_gpl));
237 return ks->value;
240 /* Now try modules. */
241 list_for_each_entry(mod, &modules, list) {
242 *owner = mod;
243 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
244 if (ks) {
245 *crc = symversion(mod->crcs, (ks - mod->syms));
246 return ks->value;
249 if (gplok) {
250 ks = lookup_symbol(name, mod->gpl_syms,
251 mod->gpl_syms + mod->num_gpl_syms);
252 if (ks) {
253 *crc = symversion(mod->gpl_crcs,
254 (ks - mod->gpl_syms));
255 return ks->value;
258 ks = lookup_symbol(name, mod->unused_syms, mod->unused_syms + mod->num_unused_syms);
259 if (ks) {
260 printk_unused_warning(name);
261 *crc = symversion(mod->unused_crcs, (ks - mod->unused_syms));
262 return ks->value;
265 if (gplok) {
266 ks = lookup_symbol(name, mod->unused_gpl_syms,
267 mod->unused_gpl_syms + mod->num_unused_gpl_syms);
268 if (ks) {
269 printk_unused_warning(name);
270 *crc = symversion(mod->unused_gpl_crcs,
271 (ks - mod->unused_gpl_syms));
272 return ks->value;
275 ks = lookup_symbol(name, mod->gpl_future_syms,
276 (mod->gpl_future_syms +
277 mod->num_gpl_future_syms));
278 if (ks) {
279 if (!gplok) {
280 printk(KERN_WARNING "Symbol %s is being used "
281 "by a non-GPL module, which will not "
282 "be allowed in the future\n", name);
283 printk(KERN_WARNING "Please see the file "
284 "Documentation/feature-removal-schedule.txt "
285 "in the kernel source tree for more "
286 "details.\n");
288 *crc = symversion(mod->gpl_future_crcs,
289 (ks - mod->gpl_future_syms));
290 return ks->value;
293 DEBUGP("Failed to find symbol %s\n", name);
294 return -ENOENT;
297 /* Search for module by name: must hold module_mutex. */
298 static struct module *find_module(const char *name)
300 struct module *mod;
302 list_for_each_entry(mod, &modules, list) {
303 if (strcmp(mod->name, name) == 0)
304 return mod;
306 return NULL;
309 #ifdef CONFIG_SMP
310 /* Number of blocks used and allocated. */
311 static unsigned int pcpu_num_used, pcpu_num_allocated;
312 /* Size of each block. -ve means used. */
313 static int *pcpu_size;
315 static int split_block(unsigned int i, unsigned short size)
317 /* Reallocation required? */
318 if (pcpu_num_used + 1 > pcpu_num_allocated) {
319 int *new;
321 new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2,
322 GFP_KERNEL);
323 if (!new)
324 return 0;
326 pcpu_num_allocated *= 2;
327 pcpu_size = new;
330 /* Insert a new subblock */
331 memmove(&pcpu_size[i+1], &pcpu_size[i],
332 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
333 pcpu_num_used++;
335 pcpu_size[i+1] -= size;
336 pcpu_size[i] = size;
337 return 1;
340 static inline unsigned int block_size(int val)
342 if (val < 0)
343 return -val;
344 return val;
347 static void *percpu_modalloc(unsigned long size, unsigned long align,
348 const char *name)
350 unsigned long extra;
351 unsigned int i;
352 void *ptr;
354 if (align > PAGE_SIZE) {
355 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
356 name, align, PAGE_SIZE);
357 align = PAGE_SIZE;
360 ptr = __per_cpu_start;
361 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
362 /* Extra for alignment requirement. */
363 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
364 BUG_ON(i == 0 && extra != 0);
366 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
367 continue;
369 /* Transfer extra to previous block. */
370 if (pcpu_size[i-1] < 0)
371 pcpu_size[i-1] -= extra;
372 else
373 pcpu_size[i-1] += extra;
374 pcpu_size[i] -= extra;
375 ptr += extra;
377 /* Split block if warranted */
378 if (pcpu_size[i] - size > sizeof(unsigned long))
379 if (!split_block(i, size))
380 return NULL;
382 /* Mark allocated */
383 pcpu_size[i] = -pcpu_size[i];
384 return ptr;
387 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
388 size);
389 return NULL;
392 static void percpu_modfree(void *freeme)
394 unsigned int i;
395 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
397 /* First entry is core kernel percpu data. */
398 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
399 if (ptr == freeme) {
400 pcpu_size[i] = -pcpu_size[i];
401 goto free;
404 BUG();
406 free:
407 /* Merge with previous? */
408 if (pcpu_size[i-1] >= 0) {
409 pcpu_size[i-1] += pcpu_size[i];
410 pcpu_num_used--;
411 memmove(&pcpu_size[i], &pcpu_size[i+1],
412 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
413 i--;
415 /* Merge with next? */
416 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
417 pcpu_size[i] += pcpu_size[i+1];
418 pcpu_num_used--;
419 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
420 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
424 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
425 Elf_Shdr *sechdrs,
426 const char *secstrings)
428 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
431 static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
433 int cpu;
435 for_each_possible_cpu(cpu)
436 memcpy(pcpudest + per_cpu_offset(cpu), from, size);
439 static int percpu_modinit(void)
441 pcpu_num_used = 2;
442 pcpu_num_allocated = 2;
443 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
444 GFP_KERNEL);
445 /* Static in-kernel percpu data (used). */
446 pcpu_size[0] = -(__per_cpu_end-__per_cpu_start);
447 /* Free room. */
448 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
449 if (pcpu_size[1] < 0) {
450 printk(KERN_ERR "No per-cpu room for modules.\n");
451 pcpu_num_used = 1;
454 return 0;
456 __initcall(percpu_modinit);
457 #else /* ... !CONFIG_SMP */
458 static inline void *percpu_modalloc(unsigned long size, unsigned long align,
459 const char *name)
461 return NULL;
463 static inline void percpu_modfree(void *pcpuptr)
465 BUG();
467 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
468 Elf_Shdr *sechdrs,
469 const char *secstrings)
471 return 0;
473 static inline void percpu_modcopy(void *pcpudst, const void *src,
474 unsigned long size)
476 /* pcpusec should be 0, and size of that section should be 0. */
477 BUG_ON(size != 0);
479 #endif /* CONFIG_SMP */
481 #define MODINFO_ATTR(field) \
482 static void setup_modinfo_##field(struct module *mod, const char *s) \
484 mod->field = kstrdup(s, GFP_KERNEL); \
486 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
487 struct module *mod, char *buffer) \
489 return sprintf(buffer, "%s\n", mod->field); \
491 static int modinfo_##field##_exists(struct module *mod) \
493 return mod->field != NULL; \
495 static void free_modinfo_##field(struct module *mod) \
497 kfree(mod->field); \
498 mod->field = NULL; \
500 static struct module_attribute modinfo_##field = { \
501 .attr = { .name = __stringify(field), .mode = 0444 }, \
502 .show = show_modinfo_##field, \
503 .setup = setup_modinfo_##field, \
504 .test = modinfo_##field##_exists, \
505 .free = free_modinfo_##field, \
508 MODINFO_ATTR(version);
509 MODINFO_ATTR(srcversion);
511 static char last_unloaded_module[MODULE_NAME_LEN+1];
513 #ifdef CONFIG_MODULE_UNLOAD
514 /* Init the unload section of the module. */
515 static void module_unload_init(struct module *mod)
517 unsigned int i;
519 INIT_LIST_HEAD(&mod->modules_which_use_me);
520 for (i = 0; i < NR_CPUS; i++)
521 local_set(&mod->ref[i].count, 0);
522 /* Hold reference count during initialization. */
523 local_set(&mod->ref[raw_smp_processor_id()].count, 1);
524 /* Backwards compatibility macros put refcount during init. */
525 mod->waiter = current;
528 /* modules using other modules */
529 struct module_use
531 struct list_head list;
532 struct module *module_which_uses;
535 /* Does a already use b? */
536 static int already_uses(struct module *a, struct module *b)
538 struct module_use *use;
540 list_for_each_entry(use, &b->modules_which_use_me, list) {
541 if (use->module_which_uses == a) {
542 DEBUGP("%s uses %s!\n", a->name, b->name);
543 return 1;
546 DEBUGP("%s does not use %s!\n", a->name, b->name);
547 return 0;
550 /* Module a uses b */
551 static int use_module(struct module *a, struct module *b)
553 struct module_use *use;
554 int no_warn, err;
556 if (b == NULL || already_uses(a, b)) return 1;
558 /* If we're interrupted or time out, we fail. */
559 if (wait_event_interruptible_timeout(
560 module_wq, (err = strong_try_module_get(b)) != -EBUSY,
561 30 * HZ) <= 0) {
562 printk("%s: gave up waiting for init of module %s.\n",
563 a->name, b->name);
564 return 0;
567 /* If strong_try_module_get() returned a different error, we fail. */
568 if (err)
569 return 0;
571 DEBUGP("Allocating new usage for %s.\n", a->name);
572 use = kmalloc(sizeof(*use), GFP_ATOMIC);
573 if (!use) {
574 printk("%s: out of memory loading\n", a->name);
575 module_put(b);
576 return 0;
579 use->module_which_uses = a;
580 list_add(&use->list, &b->modules_which_use_me);
581 no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
582 return 1;
585 /* Clear the unload stuff of the module. */
586 static void module_unload_free(struct module *mod)
588 struct module *i;
590 list_for_each_entry(i, &modules, list) {
591 struct module_use *use;
593 list_for_each_entry(use, &i->modules_which_use_me, list) {
594 if (use->module_which_uses == mod) {
595 DEBUGP("%s unusing %s\n", mod->name, i->name);
596 module_put(i);
597 list_del(&use->list);
598 kfree(use);
599 sysfs_remove_link(i->holders_dir, mod->name);
600 /* There can be at most one match. */
601 break;
607 #ifdef CONFIG_MODULE_FORCE_UNLOAD
608 static inline int try_force_unload(unsigned int flags)
610 int ret = (flags & O_TRUNC);
611 if (ret)
612 add_taint(TAINT_FORCED_RMMOD);
613 return ret;
615 #else
616 static inline int try_force_unload(unsigned int flags)
618 return 0;
620 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
622 struct stopref
624 struct module *mod;
625 int flags;
626 int *forced;
629 /* Whole machine is stopped with interrupts off when this runs. */
630 static int __try_stop_module(void *_sref)
632 struct stopref *sref = _sref;
634 /* If it's not unused, quit unless we are told to block. */
635 if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
636 if (!(*sref->forced = try_force_unload(sref->flags)))
637 return -EWOULDBLOCK;
640 /* Mark it as dying. */
641 sref->mod->state = MODULE_STATE_GOING;
642 return 0;
645 static int try_stop_module(struct module *mod, int flags, int *forced)
647 struct stopref sref = { mod, flags, forced };
649 return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
652 unsigned int module_refcount(struct module *mod)
654 unsigned int i, total = 0;
656 for (i = 0; i < NR_CPUS; i++)
657 total += local_read(&mod->ref[i].count);
658 return total;
660 EXPORT_SYMBOL(module_refcount);
662 /* This exists whether we can unload or not */
663 static void free_module(struct module *mod);
665 static void wait_for_zero_refcount(struct module *mod)
667 /* Since we might sleep for some time, drop the semaphore first */
668 mutex_unlock(&module_mutex);
669 for (;;) {
670 DEBUGP("Looking at refcount...\n");
671 set_current_state(TASK_UNINTERRUPTIBLE);
672 if (module_refcount(mod) == 0)
673 break;
674 schedule();
676 current->state = TASK_RUNNING;
677 mutex_lock(&module_mutex);
680 asmlinkage long
681 sys_delete_module(const char __user *name_user, unsigned int flags)
683 struct module *mod;
684 char name[MODULE_NAME_LEN];
685 int ret, forced = 0;
687 if (!capable(CAP_SYS_MODULE))
688 return -EPERM;
690 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
691 return -EFAULT;
692 name[MODULE_NAME_LEN-1] = '\0';
694 if (mutex_lock_interruptible(&module_mutex) != 0)
695 return -EINTR;
697 mod = find_module(name);
698 if (!mod) {
699 ret = -ENOENT;
700 goto out;
703 if (!list_empty(&mod->modules_which_use_me)) {
704 /* Other modules depend on us: get rid of them first. */
705 ret = -EWOULDBLOCK;
706 goto out;
709 /* Doing init or already dying? */
710 if (mod->state != MODULE_STATE_LIVE) {
711 /* FIXME: if (force), slam module count and wake up
712 waiter --RR */
713 DEBUGP("%s already dying\n", mod->name);
714 ret = -EBUSY;
715 goto out;
718 /* If it has an init func, it must have an exit func to unload */
719 if (mod->init && !mod->exit) {
720 forced = try_force_unload(flags);
721 if (!forced) {
722 /* This module can't be removed */
723 ret = -EBUSY;
724 goto out;
728 /* Set this up before setting mod->state */
729 mod->waiter = current;
731 /* Stop the machine so refcounts can't move and disable module. */
732 ret = try_stop_module(mod, flags, &forced);
733 if (ret != 0)
734 goto out;
736 /* Never wait if forced. */
737 if (!forced && module_refcount(mod) != 0)
738 wait_for_zero_refcount(mod);
740 /* Final destruction now noone is using it. */
741 if (mod->exit != NULL) {
742 mutex_unlock(&module_mutex);
743 mod->exit();
744 mutex_lock(&module_mutex);
746 /* Store the name of the last unloaded module for diagnostic purposes */
747 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
748 free_module(mod);
750 out:
751 mutex_unlock(&module_mutex);
752 return ret;
755 static void print_unload_info(struct seq_file *m, struct module *mod)
757 struct module_use *use;
758 int printed_something = 0;
760 seq_printf(m, " %u ", module_refcount(mod));
762 /* Always include a trailing , so userspace can differentiate
763 between this and the old multi-field proc format. */
764 list_for_each_entry(use, &mod->modules_which_use_me, list) {
765 printed_something = 1;
766 seq_printf(m, "%s,", use->module_which_uses->name);
769 if (mod->init != NULL && mod->exit == NULL) {
770 printed_something = 1;
771 seq_printf(m, "[permanent],");
774 if (!printed_something)
775 seq_printf(m, "-");
778 void __symbol_put(const char *symbol)
780 struct module *owner;
781 const unsigned long *crc;
783 preempt_disable();
784 if (IS_ERR_VALUE(__find_symbol(symbol, &owner, &crc, 1)))
785 BUG();
786 module_put(owner);
787 preempt_enable();
789 EXPORT_SYMBOL(__symbol_put);
791 void symbol_put_addr(void *addr)
793 struct module *modaddr;
795 if (core_kernel_text((unsigned long)addr))
796 return;
798 if (!(modaddr = module_text_address((unsigned long)addr)))
799 BUG();
800 module_put(modaddr);
802 EXPORT_SYMBOL_GPL(symbol_put_addr);
804 static ssize_t show_refcnt(struct module_attribute *mattr,
805 struct module *mod, char *buffer)
807 return sprintf(buffer, "%u\n", module_refcount(mod));
810 static struct module_attribute refcnt = {
811 .attr = { .name = "refcnt", .mode = 0444 },
812 .show = show_refcnt,
815 void module_put(struct module *module)
817 if (module) {
818 unsigned int cpu = get_cpu();
819 local_dec(&module->ref[cpu].count);
820 /* Maybe they're waiting for us to drop reference? */
821 if (unlikely(!module_is_live(module)))
822 wake_up_process(module->waiter);
823 put_cpu();
826 EXPORT_SYMBOL(module_put);
828 #else /* !CONFIG_MODULE_UNLOAD */
829 static void print_unload_info(struct seq_file *m, struct module *mod)
831 /* We don't know the usage count, or what modules are using. */
832 seq_printf(m, " - -");
835 static inline void module_unload_free(struct module *mod)
839 static inline int use_module(struct module *a, struct module *b)
841 return strong_try_module_get(b) == 0;
844 static inline void module_unload_init(struct module *mod)
847 #endif /* CONFIG_MODULE_UNLOAD */
849 static ssize_t show_initstate(struct module_attribute *mattr,
850 struct module *mod, char *buffer)
852 const char *state = "unknown";
854 switch (mod->state) {
855 case MODULE_STATE_LIVE:
856 state = "live";
857 break;
858 case MODULE_STATE_COMING:
859 state = "coming";
860 break;
861 case MODULE_STATE_GOING:
862 state = "going";
863 break;
865 return sprintf(buffer, "%s\n", state);
868 static struct module_attribute initstate = {
869 .attr = { .name = "initstate", .mode = 0444 },
870 .show = show_initstate,
873 static struct module_attribute *modinfo_attrs[] = {
874 &modinfo_version,
875 &modinfo_srcversion,
876 &initstate,
877 #ifdef CONFIG_MODULE_UNLOAD
878 &refcnt,
879 #endif
880 NULL,
883 static const char vermagic[] = VERMAGIC_STRING;
885 #ifdef CONFIG_MODVERSIONS
886 static int check_version(Elf_Shdr *sechdrs,
887 unsigned int versindex,
888 const char *symname,
889 struct module *mod,
890 const unsigned long *crc)
892 unsigned int i, num_versions;
893 struct modversion_info *versions;
895 /* Exporting module didn't supply crcs? OK, we're already tainted. */
896 if (!crc)
897 return 1;
899 versions = (void *) sechdrs[versindex].sh_addr;
900 num_versions = sechdrs[versindex].sh_size
901 / sizeof(struct modversion_info);
903 for (i = 0; i < num_versions; i++) {
904 if (strcmp(versions[i].name, symname) != 0)
905 continue;
907 if (versions[i].crc == *crc)
908 return 1;
909 printk("%s: disagrees about version of symbol %s\n",
910 mod->name, symname);
911 DEBUGP("Found checksum %lX vs module %lX\n",
912 *crc, versions[i].crc);
913 return 0;
915 /* Not in module's version table. OK, but that taints the kernel. */
916 if (!(tainted & TAINT_FORCED_MODULE))
917 printk("%s: no version for \"%s\" found: kernel tainted.\n",
918 mod->name, symname);
919 add_taint_module(mod, TAINT_FORCED_MODULE);
920 return 1;
923 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
924 unsigned int versindex,
925 struct module *mod)
927 const unsigned long *crc;
928 struct module *owner;
930 if (IS_ERR_VALUE(__find_symbol("struct_module",
931 &owner, &crc, 1)))
932 BUG();
933 return check_version(sechdrs, versindex, "struct_module", mod,
934 crc);
937 /* First part is kernel version, which we ignore. */
938 static inline int same_magic(const char *amagic, const char *bmagic)
940 amagic += strcspn(amagic, " ");
941 bmagic += strcspn(bmagic, " ");
942 return strcmp(amagic, bmagic) == 0;
944 #else
945 static inline int check_version(Elf_Shdr *sechdrs,
946 unsigned int versindex,
947 const char *symname,
948 struct module *mod,
949 const unsigned long *crc)
951 return 1;
954 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
955 unsigned int versindex,
956 struct module *mod)
958 return 1;
961 static inline int same_magic(const char *amagic, const char *bmagic)
963 return strcmp(amagic, bmagic) == 0;
965 #endif /* CONFIG_MODVERSIONS */
967 /* Resolve a symbol for this module. I.e. if we find one, record usage.
968 Must be holding module_mutex. */
969 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
970 unsigned int versindex,
971 const char *name,
972 struct module *mod)
974 struct module *owner;
975 unsigned long ret;
976 const unsigned long *crc;
978 ret = __find_symbol(name, &owner, &crc,
979 !(mod->taints & TAINT_PROPRIETARY_MODULE));
980 if (!IS_ERR_VALUE(ret)) {
981 /* use_module can fail due to OOM,
982 or module initialization or unloading */
983 if (!check_version(sechdrs, versindex, name, mod, crc) ||
984 !use_module(mod, owner))
985 ret = -EINVAL;
987 return ret;
991 * /sys/module/foo/sections stuff
992 * J. Corbet <corbet@lwn.net>
994 #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
995 static ssize_t module_sect_show(struct module_attribute *mattr,
996 struct module *mod, char *buf)
998 struct module_sect_attr *sattr =
999 container_of(mattr, struct module_sect_attr, mattr);
1000 return sprintf(buf, "0x%lx\n", sattr->address);
1003 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1005 int section;
1007 for (section = 0; section < sect_attrs->nsections; section++)
1008 kfree(sect_attrs->attrs[section].name);
1009 kfree(sect_attrs);
1012 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1013 char *secstrings, Elf_Shdr *sechdrs)
1015 unsigned int nloaded = 0, i, size[2];
1016 struct module_sect_attrs *sect_attrs;
1017 struct module_sect_attr *sattr;
1018 struct attribute **gattr;
1020 /* Count loaded sections and allocate structures */
1021 for (i = 0; i < nsect; i++)
1022 if (sechdrs[i].sh_flags & SHF_ALLOC)
1023 nloaded++;
1024 size[0] = ALIGN(sizeof(*sect_attrs)
1025 + nloaded * sizeof(sect_attrs->attrs[0]),
1026 sizeof(sect_attrs->grp.attrs[0]));
1027 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1028 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1029 if (sect_attrs == NULL)
1030 return;
1032 /* Setup section attributes. */
1033 sect_attrs->grp.name = "sections";
1034 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1036 sect_attrs->nsections = 0;
1037 sattr = &sect_attrs->attrs[0];
1038 gattr = &sect_attrs->grp.attrs[0];
1039 for (i = 0; i < nsect; i++) {
1040 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1041 continue;
1042 sattr->address = sechdrs[i].sh_addr;
1043 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1044 GFP_KERNEL);
1045 if (sattr->name == NULL)
1046 goto out;
1047 sect_attrs->nsections++;
1048 sattr->mattr.show = module_sect_show;
1049 sattr->mattr.store = NULL;
1050 sattr->mattr.attr.name = sattr->name;
1051 sattr->mattr.attr.mode = S_IRUGO;
1052 *(gattr++) = &(sattr++)->mattr.attr;
1054 *gattr = NULL;
1056 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1057 goto out;
1059 mod->sect_attrs = sect_attrs;
1060 return;
1061 out:
1062 free_sect_attrs(sect_attrs);
1065 static void remove_sect_attrs(struct module *mod)
1067 if (mod->sect_attrs) {
1068 sysfs_remove_group(&mod->mkobj.kobj,
1069 &mod->sect_attrs->grp);
1070 /* We are positive that no one is using any sect attrs
1071 * at this point. Deallocate immediately. */
1072 free_sect_attrs(mod->sect_attrs);
1073 mod->sect_attrs = NULL;
1078 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1081 struct module_notes_attrs {
1082 struct kobject *dir;
1083 unsigned int notes;
1084 struct bin_attribute attrs[0];
1087 static ssize_t module_notes_read(struct kobject *kobj,
1088 struct bin_attribute *bin_attr,
1089 char *buf, loff_t pos, size_t count)
1092 * The caller checked the pos and count against our size.
1094 memcpy(buf, bin_attr->private + pos, count);
1095 return count;
1098 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1099 unsigned int i)
1101 if (notes_attrs->dir) {
1102 while (i-- > 0)
1103 sysfs_remove_bin_file(notes_attrs->dir,
1104 &notes_attrs->attrs[i]);
1105 kobject_del(notes_attrs->dir);
1107 kfree(notes_attrs);
1110 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1111 char *secstrings, Elf_Shdr *sechdrs)
1113 unsigned int notes, loaded, i;
1114 struct module_notes_attrs *notes_attrs;
1115 struct bin_attribute *nattr;
1117 /* Count notes sections and allocate structures. */
1118 notes = 0;
1119 for (i = 0; i < nsect; i++)
1120 if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
1121 (sechdrs[i].sh_type == SHT_NOTE))
1122 ++notes;
1124 if (notes == 0)
1125 return;
1127 notes_attrs = kzalloc(sizeof(*notes_attrs)
1128 + notes * sizeof(notes_attrs->attrs[0]),
1129 GFP_KERNEL);
1130 if (notes_attrs == NULL)
1131 return;
1133 notes_attrs->notes = notes;
1134 nattr = &notes_attrs->attrs[0];
1135 for (loaded = i = 0; i < nsect; ++i) {
1136 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1137 continue;
1138 if (sechdrs[i].sh_type == SHT_NOTE) {
1139 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1140 nattr->attr.mode = S_IRUGO;
1141 nattr->size = sechdrs[i].sh_size;
1142 nattr->private = (void *) sechdrs[i].sh_addr;
1143 nattr->read = module_notes_read;
1144 ++nattr;
1146 ++loaded;
1149 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1150 if (!notes_attrs->dir)
1151 goto out;
1153 for (i = 0; i < notes; ++i)
1154 if (sysfs_create_bin_file(notes_attrs->dir,
1155 &notes_attrs->attrs[i]))
1156 goto out;
1158 mod->notes_attrs = notes_attrs;
1159 return;
1161 out:
1162 free_notes_attrs(notes_attrs, i);
1165 static void remove_notes_attrs(struct module *mod)
1167 if (mod->notes_attrs)
1168 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1171 #else
1173 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1174 char *sectstrings, Elf_Shdr *sechdrs)
1178 static inline void remove_sect_attrs(struct module *mod)
1182 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1183 char *sectstrings, Elf_Shdr *sechdrs)
1187 static inline void remove_notes_attrs(struct module *mod)
1190 #endif
1192 #ifdef CONFIG_SYSFS
1193 int module_add_modinfo_attrs(struct module *mod)
1195 struct module_attribute *attr;
1196 struct module_attribute *temp_attr;
1197 int error = 0;
1198 int i;
1200 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1201 (ARRAY_SIZE(modinfo_attrs) + 1)),
1202 GFP_KERNEL);
1203 if (!mod->modinfo_attrs)
1204 return -ENOMEM;
1206 temp_attr = mod->modinfo_attrs;
1207 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1208 if (!attr->test ||
1209 (attr->test && attr->test(mod))) {
1210 memcpy(temp_attr, attr, sizeof(*temp_attr));
1211 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1212 ++temp_attr;
1215 return error;
1218 void module_remove_modinfo_attrs(struct module *mod)
1220 struct module_attribute *attr;
1221 int i;
1223 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1224 /* pick a field to test for end of list */
1225 if (!attr->attr.name)
1226 break;
1227 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1228 if (attr->free)
1229 attr->free(mod);
1231 kfree(mod->modinfo_attrs);
1234 int mod_sysfs_init(struct module *mod)
1236 int err;
1237 struct kobject *kobj;
1239 if (!module_sysfs_initialized) {
1240 printk(KERN_ERR "%s: module sysfs not initialized\n",
1241 mod->name);
1242 err = -EINVAL;
1243 goto out;
1246 kobj = kset_find_obj(module_kset, mod->name);
1247 if (kobj) {
1248 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1249 kobject_put(kobj);
1250 err = -EINVAL;
1251 goto out;
1254 mod->mkobj.mod = mod;
1256 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1257 mod->mkobj.kobj.kset = module_kset;
1258 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1259 "%s", mod->name);
1260 if (err)
1261 kobject_put(&mod->mkobj.kobj);
1263 /* delay uevent until full sysfs population */
1264 out:
1265 return err;
1268 int mod_sysfs_setup(struct module *mod,
1269 struct kernel_param *kparam,
1270 unsigned int num_params)
1272 int err;
1274 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1275 if (!mod->holders_dir) {
1276 err = -ENOMEM;
1277 goto out_unreg;
1280 err = module_param_sysfs_setup(mod, kparam, num_params);
1281 if (err)
1282 goto out_unreg_holders;
1284 err = module_add_modinfo_attrs(mod);
1285 if (err)
1286 goto out_unreg_param;
1288 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1289 return 0;
1291 out_unreg_param:
1292 module_param_sysfs_remove(mod);
1293 out_unreg_holders:
1294 kobject_put(mod->holders_dir);
1295 out_unreg:
1296 kobject_put(&mod->mkobj.kobj);
1297 return err;
1299 #endif
1301 static void mod_kobject_remove(struct module *mod)
1303 module_remove_modinfo_attrs(mod);
1304 module_param_sysfs_remove(mod);
1305 kobject_put(mod->mkobj.drivers_dir);
1306 kobject_put(mod->holders_dir);
1307 kobject_put(&mod->mkobj.kobj);
1311 * link the module with the whole machine is stopped with interrupts off
1312 * - this defends against kallsyms not taking locks
1314 static int __link_module(void *_mod)
1316 struct module *mod = _mod;
1317 list_add(&mod->list, &modules);
1318 return 0;
1322 * unlink the module with the whole machine is stopped with interrupts off
1323 * - this defends against kallsyms not taking locks
1325 static int __unlink_module(void *_mod)
1327 struct module *mod = _mod;
1328 list_del(&mod->list);
1329 return 0;
1332 /* Free a module, remove from lists, etc (must hold module_mutex). */
1333 static void free_module(struct module *mod)
1335 /* Delete from various lists */
1336 stop_machine_run(__unlink_module, mod, NR_CPUS);
1337 remove_notes_attrs(mod);
1338 remove_sect_attrs(mod);
1339 mod_kobject_remove(mod);
1341 unwind_remove_table(mod->unwind_info, 0);
1343 /* Arch-specific cleanup. */
1344 module_arch_cleanup(mod);
1346 /* Module unload stuff */
1347 module_unload_free(mod);
1349 /* This may be NULL, but that's OK */
1350 module_free(mod, mod->module_init);
1351 kfree(mod->args);
1352 if (mod->percpu)
1353 percpu_modfree(mod->percpu);
1355 /* Free lock-classes: */
1356 lockdep_free_key_range(mod->module_core, mod->core_size);
1358 /* Finally, free the core (containing the module structure) */
1359 module_free(mod, mod->module_core);
1362 void *__symbol_get(const char *symbol)
1364 struct module *owner;
1365 unsigned long value;
1366 const unsigned long *crc;
1368 preempt_disable();
1369 value = __find_symbol(symbol, &owner, &crc, 1);
1370 if (IS_ERR_VALUE(value))
1371 value = 0;
1372 else if (strong_try_module_get(owner))
1373 value = 0;
1374 preempt_enable();
1376 return (void *)value;
1378 EXPORT_SYMBOL_GPL(__symbol_get);
1381 * Ensure that an exported symbol [global namespace] does not already exist
1382 * in the kernel or in some other module's exported symbol table.
1384 static int verify_export_symbols(struct module *mod)
1386 const char *name = NULL;
1387 unsigned long i, ret = 0;
1388 struct module *owner;
1389 const unsigned long *crc;
1391 for (i = 0; i < mod->num_syms; i++)
1392 if (!IS_ERR_VALUE(__find_symbol(mod->syms[i].name,
1393 &owner, &crc, 1))) {
1394 name = mod->syms[i].name;
1395 ret = -ENOEXEC;
1396 goto dup;
1399 for (i = 0; i < mod->num_gpl_syms; i++)
1400 if (!IS_ERR_VALUE(__find_symbol(mod->gpl_syms[i].name,
1401 &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 (!IS_ERR_VALUE(sym[i].st_value))
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"));
1937 * ndiswrapper is under GPL by itself, but loads proprietary modules.
1938 * Don't use add_taint_module(), as it would prevent ndiswrapper from
1939 * using GPL-only symbols it needs.
1941 if (strcmp(mod->name, "ndiswrapper") == 0)
1942 add_taint(TAINT_PROPRIETARY_MODULE);
1944 /* driverloader was caught wrongly pretending to be under GPL */
1945 if (strcmp(mod->name, "driverloader") == 0)
1946 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1948 /* Set up MODINFO_ATTR fields */
1949 setup_modinfo(mod, sechdrs, infoindex);
1951 /* Fix up syms, so that st_value is a pointer to location. */
1952 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
1953 mod);
1954 if (err < 0)
1955 goto cleanup;
1957 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
1958 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
1959 mod->syms = (void *)sechdrs[exportindex].sh_addr;
1960 if (crcindex)
1961 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
1962 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
1963 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
1964 if (gplcrcindex)
1965 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
1966 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
1967 sizeof(*mod->gpl_future_syms);
1968 mod->num_unused_syms = sechdrs[unusedindex].sh_size /
1969 sizeof(*mod->unused_syms);
1970 mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
1971 sizeof(*mod->unused_gpl_syms);
1972 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
1973 if (gplfuturecrcindex)
1974 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
1976 mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
1977 if (unusedcrcindex)
1978 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
1979 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
1980 if (unusedgplcrcindex)
1981 mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr;
1983 #ifdef CONFIG_MODVERSIONS
1984 if ((mod->num_syms && !crcindex) ||
1985 (mod->num_gpl_syms && !gplcrcindex) ||
1986 (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
1987 (mod->num_unused_syms && !unusedcrcindex) ||
1988 (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
1989 printk(KERN_WARNING "%s: No versions for exported symbols."
1990 " Tainting kernel.\n", mod->name);
1991 add_taint_module(mod, TAINT_FORCED_MODULE);
1993 #endif
1994 markersindex = find_sec(hdr, sechdrs, secstrings, "__markers");
1995 markersstringsindex = find_sec(hdr, sechdrs, secstrings,
1996 "__markers_strings");
1998 /* Now do relocations. */
1999 for (i = 1; i < hdr->e_shnum; i++) {
2000 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2001 unsigned int info = sechdrs[i].sh_info;
2003 /* Not a valid relocation section? */
2004 if (info >= hdr->e_shnum)
2005 continue;
2007 /* Don't bother with non-allocated sections */
2008 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2009 continue;
2011 if (sechdrs[i].sh_type == SHT_REL)
2012 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2013 else if (sechdrs[i].sh_type == SHT_RELA)
2014 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2015 mod);
2016 if (err < 0)
2017 goto cleanup;
2019 #ifdef CONFIG_MARKERS
2020 mod->markers = (void *)sechdrs[markersindex].sh_addr;
2021 mod->num_markers =
2022 sechdrs[markersindex].sh_size / sizeof(*mod->markers);
2023 #endif
2025 /* Find duplicate symbols */
2026 err = verify_export_symbols(mod);
2028 if (err < 0)
2029 goto cleanup;
2031 /* Set up and sort exception table */
2032 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
2033 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
2034 sort_extable(extable, extable + mod->num_exentries);
2036 /* Finally, copy percpu area over. */
2037 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
2038 sechdrs[pcpuindex].sh_size);
2040 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
2042 #ifdef CONFIG_MARKERS
2043 if (!mod->taints)
2044 marker_update_probe_range(mod->markers,
2045 mod->markers + mod->num_markers);
2046 #endif
2047 err = module_finalize(hdr, sechdrs, mod);
2048 if (err < 0)
2049 goto cleanup;
2051 /* flush the icache in correct context */
2052 old_fs = get_fs();
2053 set_fs(KERNEL_DS);
2056 * Flush the instruction cache, since we've played with text.
2057 * Do it before processing of module parameters, so the module
2058 * can provide parameter accessor functions of its own.
2060 if (mod->module_init)
2061 flush_icache_range((unsigned long)mod->module_init,
2062 (unsigned long)mod->module_init
2063 + mod->init_size);
2064 flush_icache_range((unsigned long)mod->module_core,
2065 (unsigned long)mod->module_core + mod->core_size);
2067 set_fs(old_fs);
2069 mod->args = args;
2070 if (obsparmindex)
2071 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2072 mod->name);
2074 /* Now sew it into the lists so we can get lockdep and oops
2075 * info during argument parsing. Noone should access us, since
2076 * strong_try_module_get() will fail. */
2077 stop_machine_run(__link_module, mod, NR_CPUS);
2079 /* Size of section 0 is 0, so this works well if no params */
2080 err = parse_args(mod->name, mod->args,
2081 (struct kernel_param *)
2082 sechdrs[setupindex].sh_addr,
2083 sechdrs[setupindex].sh_size
2084 / sizeof(struct kernel_param),
2085 NULL);
2086 if (err < 0)
2087 goto unlink;
2089 err = mod_sysfs_setup(mod,
2090 (struct kernel_param *)
2091 sechdrs[setupindex].sh_addr,
2092 sechdrs[setupindex].sh_size
2093 / sizeof(struct kernel_param));
2094 if (err < 0)
2095 goto unlink;
2096 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2097 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2099 /* Size of section 0 is 0, so this works well if no unwind info. */
2100 mod->unwind_info = unwind_add_table(mod,
2101 (void *)sechdrs[unwindex].sh_addr,
2102 sechdrs[unwindex].sh_size);
2104 /* Get rid of temporary copy */
2105 vfree(hdr);
2107 /* Done! */
2108 return mod;
2110 unlink:
2111 stop_machine_run(__unlink_module, mod, NR_CPUS);
2112 module_arch_cleanup(mod);
2113 cleanup:
2114 kobject_del(&mod->mkobj.kobj);
2115 kobject_put(&mod->mkobj.kobj);
2116 free_unload:
2117 module_unload_free(mod);
2118 module_free(mod, mod->module_init);
2119 free_core:
2120 module_free(mod, mod->module_core);
2121 free_percpu:
2122 if (percpu)
2123 percpu_modfree(percpu);
2124 free_mod:
2125 kfree(args);
2126 free_hdr:
2127 vfree(hdr);
2128 return ERR_PTR(err);
2130 truncated:
2131 printk(KERN_ERR "Module len %lu truncated\n", len);
2132 err = -ENOEXEC;
2133 goto free_hdr;
2136 /* This is where the real work happens */
2137 asmlinkage long
2138 sys_init_module(void __user *umod,
2139 unsigned long len,
2140 const char __user *uargs)
2142 struct module *mod;
2143 int ret = 0;
2145 /* Must have permission */
2146 if (!capable(CAP_SYS_MODULE))
2147 return -EPERM;
2149 /* Only one module load at a time, please */
2150 if (mutex_lock_interruptible(&module_mutex) != 0)
2151 return -EINTR;
2153 /* Do all the hard work */
2154 mod = load_module(umod, len, uargs);
2155 if (IS_ERR(mod)) {
2156 mutex_unlock(&module_mutex);
2157 return PTR_ERR(mod);
2160 /* Drop lock so they can recurse */
2161 mutex_unlock(&module_mutex);
2163 blocking_notifier_call_chain(&module_notify_list,
2164 MODULE_STATE_COMING, mod);
2166 /* Start the module */
2167 if (mod->init != NULL)
2168 ret = mod->init();
2169 if (ret < 0) {
2170 /* Init routine failed: abort. Try to protect us from
2171 buggy refcounters. */
2172 mod->state = MODULE_STATE_GOING;
2173 synchronize_sched();
2174 module_put(mod);
2175 mutex_lock(&module_mutex);
2176 free_module(mod);
2177 mutex_unlock(&module_mutex);
2178 wake_up(&module_wq);
2179 return ret;
2182 /* Now it's a first class citizen! */
2183 mutex_lock(&module_mutex);
2184 mod->state = MODULE_STATE_LIVE;
2185 /* Drop initial reference. */
2186 module_put(mod);
2187 unwind_remove_table(mod->unwind_info, 1);
2188 module_free(mod, mod->module_init);
2189 mod->module_init = NULL;
2190 mod->init_size = 0;
2191 mod->init_text_size = 0;
2192 mutex_unlock(&module_mutex);
2193 wake_up(&module_wq);
2195 return 0;
2198 static inline int within(unsigned long addr, void *start, unsigned long size)
2200 return ((void *)addr >= start && (void *)addr < start + size);
2203 #ifdef CONFIG_KALLSYMS
2205 * This ignores the intensely annoying "mapping symbols" found
2206 * in ARM ELF files: $a, $t and $d.
2208 static inline int is_arm_mapping_symbol(const char *str)
2210 return str[0] == '$' && strchr("atd", str[1])
2211 && (str[2] == '\0' || str[2] == '.');
2214 static const char *get_ksymbol(struct module *mod,
2215 unsigned long addr,
2216 unsigned long *size,
2217 unsigned long *offset)
2219 unsigned int i, best = 0;
2220 unsigned long nextval;
2222 /* At worse, next value is at end of module */
2223 if (within(addr, mod->module_init, mod->init_size))
2224 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2225 else
2226 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2228 /* Scan for closest preceeding symbol, and next symbol. (ELF
2229 starts real symbols at 1). */
2230 for (i = 1; i < mod->num_symtab; i++) {
2231 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2232 continue;
2234 /* We ignore unnamed symbols: they're uninformative
2235 * and inserted at a whim. */
2236 if (mod->symtab[i].st_value <= addr
2237 && mod->symtab[i].st_value > mod->symtab[best].st_value
2238 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2239 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2240 best = i;
2241 if (mod->symtab[i].st_value > addr
2242 && mod->symtab[i].st_value < nextval
2243 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2244 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2245 nextval = mod->symtab[i].st_value;
2248 if (!best)
2249 return NULL;
2251 if (size)
2252 *size = nextval - mod->symtab[best].st_value;
2253 if (offset)
2254 *offset = addr - mod->symtab[best].st_value;
2255 return mod->strtab + mod->symtab[best].st_name;
2258 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2259 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2260 const char *module_address_lookup(unsigned long addr,
2261 unsigned long *size,
2262 unsigned long *offset,
2263 char **modname,
2264 char *namebuf)
2266 struct module *mod;
2267 const char *ret = NULL;
2269 preempt_disable();
2270 list_for_each_entry(mod, &modules, list) {
2271 if (within(addr, mod->module_init, mod->init_size)
2272 || within(addr, mod->module_core, mod->core_size)) {
2273 if (modname)
2274 *modname = mod->name;
2275 ret = get_ksymbol(mod, addr, size, offset);
2276 break;
2279 /* Make a copy in here where it's safe */
2280 if (ret) {
2281 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2282 ret = namebuf;
2284 preempt_enable();
2285 return ret;
2288 int lookup_module_symbol_name(unsigned long addr, char *symname)
2290 struct module *mod;
2292 preempt_disable();
2293 list_for_each_entry(mod, &modules, list) {
2294 if (within(addr, mod->module_init, mod->init_size) ||
2295 within(addr, mod->module_core, mod->core_size)) {
2296 const char *sym;
2298 sym = get_ksymbol(mod, addr, NULL, NULL);
2299 if (!sym)
2300 goto out;
2301 strlcpy(symname, sym, KSYM_NAME_LEN);
2302 preempt_enable();
2303 return 0;
2306 out:
2307 preempt_enable();
2308 return -ERANGE;
2311 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2312 unsigned long *offset, char *modname, char *name)
2314 struct module *mod;
2316 preempt_disable();
2317 list_for_each_entry(mod, &modules, list) {
2318 if (within(addr, mod->module_init, mod->init_size) ||
2319 within(addr, mod->module_core, mod->core_size)) {
2320 const char *sym;
2322 sym = get_ksymbol(mod, addr, size, offset);
2323 if (!sym)
2324 goto out;
2325 if (modname)
2326 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2327 if (name)
2328 strlcpy(name, sym, KSYM_NAME_LEN);
2329 preempt_enable();
2330 return 0;
2333 out:
2334 preempt_enable();
2335 return -ERANGE;
2338 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2339 char *name, char *module_name, int *exported)
2341 struct module *mod;
2343 preempt_disable();
2344 list_for_each_entry(mod, &modules, list) {
2345 if (symnum < mod->num_symtab) {
2346 *value = mod->symtab[symnum].st_value;
2347 *type = mod->symtab[symnum].st_info;
2348 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2349 KSYM_NAME_LEN);
2350 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2351 *exported = is_exported(name, mod);
2352 preempt_enable();
2353 return 0;
2355 symnum -= mod->num_symtab;
2357 preempt_enable();
2358 return -ERANGE;
2361 static unsigned long mod_find_symname(struct module *mod, const char *name)
2363 unsigned int i;
2365 for (i = 0; i < mod->num_symtab; i++)
2366 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2367 mod->symtab[i].st_info != 'U')
2368 return mod->symtab[i].st_value;
2369 return 0;
2372 /* Look for this name: can be of form module:name. */
2373 unsigned long module_kallsyms_lookup_name(const char *name)
2375 struct module *mod;
2376 char *colon;
2377 unsigned long ret = 0;
2379 /* Don't lock: we're in enough trouble already. */
2380 preempt_disable();
2381 if ((colon = strchr(name, ':')) != NULL) {
2382 *colon = '\0';
2383 if ((mod = find_module(name)) != NULL)
2384 ret = mod_find_symname(mod, colon+1);
2385 *colon = ':';
2386 } else {
2387 list_for_each_entry(mod, &modules, list)
2388 if ((ret = mod_find_symname(mod, name)) != 0)
2389 break;
2391 preempt_enable();
2392 return ret;
2394 #endif /* CONFIG_KALLSYMS */
2396 /* Called by the /proc file system to return a list of modules. */
2397 static void *m_start(struct seq_file *m, loff_t *pos)
2399 mutex_lock(&module_mutex);
2400 return seq_list_start(&modules, *pos);
2403 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2405 return seq_list_next(p, &modules, pos);
2408 static void m_stop(struct seq_file *m, void *p)
2410 mutex_unlock(&module_mutex);
2413 static char *module_flags(struct module *mod, char *buf)
2415 int bx = 0;
2417 if (mod->taints ||
2418 mod->state == MODULE_STATE_GOING ||
2419 mod->state == MODULE_STATE_COMING) {
2420 buf[bx++] = '(';
2421 if (mod->taints & TAINT_PROPRIETARY_MODULE)
2422 buf[bx++] = 'P';
2423 if (mod->taints & TAINT_FORCED_MODULE)
2424 buf[bx++] = 'F';
2426 * TAINT_FORCED_RMMOD: could be added.
2427 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2428 * apply to modules.
2431 /* Show a - for module-is-being-unloaded */
2432 if (mod->state == MODULE_STATE_GOING)
2433 buf[bx++] = '-';
2434 /* Show a + for module-is-being-loaded */
2435 if (mod->state == MODULE_STATE_COMING)
2436 buf[bx++] = '+';
2437 buf[bx++] = ')';
2439 buf[bx] = '\0';
2441 return buf;
2444 static int m_show(struct seq_file *m, void *p)
2446 struct module *mod = list_entry(p, struct module, list);
2447 char buf[8];
2449 seq_printf(m, "%s %lu",
2450 mod->name, mod->init_size + mod->core_size);
2451 print_unload_info(m, mod);
2453 /* Informative for users. */
2454 seq_printf(m, " %s",
2455 mod->state == MODULE_STATE_GOING ? "Unloading":
2456 mod->state == MODULE_STATE_COMING ? "Loading":
2457 "Live");
2458 /* Used by oprofile and other similar tools. */
2459 seq_printf(m, " 0x%p", mod->module_core);
2461 /* Taints info */
2462 if (mod->taints)
2463 seq_printf(m, " %s", module_flags(mod, buf));
2465 seq_printf(m, "\n");
2466 return 0;
2469 /* Format: modulename size refcount deps address
2471 Where refcount is a number or -, and deps is a comma-separated list
2472 of depends or -.
2474 const struct seq_operations modules_op = {
2475 .start = m_start,
2476 .next = m_next,
2477 .stop = m_stop,
2478 .show = m_show
2481 /* Given an address, look for it in the module exception tables. */
2482 const struct exception_table_entry *search_module_extables(unsigned long addr)
2484 const struct exception_table_entry *e = NULL;
2485 struct module *mod;
2487 preempt_disable();
2488 list_for_each_entry(mod, &modules, list) {
2489 if (mod->num_exentries == 0)
2490 continue;
2492 e = search_extable(mod->extable,
2493 mod->extable + mod->num_exentries - 1,
2494 addr);
2495 if (e)
2496 break;
2498 preempt_enable();
2500 /* Now, if we found one, we are running inside it now, hence
2501 we cannot unload the module, hence no refcnt needed. */
2502 return e;
2506 * Is this a valid module address?
2508 int is_module_address(unsigned long addr)
2510 struct module *mod;
2512 preempt_disable();
2514 list_for_each_entry(mod, &modules, list) {
2515 if (within(addr, mod->module_core, mod->core_size)) {
2516 preempt_enable();
2517 return 1;
2521 preempt_enable();
2523 return 0;
2527 /* Is this a valid kernel address? */
2528 struct module *__module_text_address(unsigned long addr)
2530 struct module *mod;
2532 list_for_each_entry(mod, &modules, list)
2533 if (within(addr, mod->module_init, mod->init_text_size)
2534 || within(addr, mod->module_core, mod->core_text_size))
2535 return mod;
2536 return NULL;
2539 struct module *module_text_address(unsigned long addr)
2541 struct module *mod;
2543 preempt_disable();
2544 mod = __module_text_address(addr);
2545 preempt_enable();
2547 return mod;
2550 /* Don't grab lock, we're oopsing. */
2551 void print_modules(void)
2553 struct module *mod;
2554 char buf[8];
2556 printk("Modules linked in:");
2557 list_for_each_entry(mod, &modules, list)
2558 printk(" %s%s", mod->name, module_flags(mod, buf));
2559 if (last_unloaded_module[0])
2560 printk(" [last unloaded: %s]", last_unloaded_module);
2561 printk("\n");
2564 #ifdef CONFIG_MODVERSIONS
2565 /* Generate the signature for struct module here, too, for modversions. */
2566 void struct_module(struct module *mod) { return; }
2567 EXPORT_SYMBOL(struct_module);
2568 #endif
2570 #ifdef CONFIG_MARKERS
2571 void module_update_markers(void)
2573 struct module *mod;
2575 mutex_lock(&module_mutex);
2576 list_for_each_entry(mod, &modules, list)
2577 if (!mod->taints)
2578 marker_update_probe_range(mod->markers,
2579 mod->markers + mod->num_markers);
2580 mutex_unlock(&module_mutex);
2582 #endif