ACPI: move wmi, asus_acpi, toshiba_acpi to drivers/platform/x86
[linux-2.6/mini2440.git] / kernel / module.c
blob1f4cc00e0c200b7c69272694d121558fd6a10d06
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/fs.h>
24 #include <linux/sysfs.h>
25 #include <linux/kernel.h>
26 #include <linux/slab.h>
27 #include <linux/vmalloc.h>
28 #include <linux/elf.h>
29 #include <linux/proc_fs.h>
30 #include <linux/seq_file.h>
31 #include <linux/syscalls.h>
32 #include <linux/fcntl.h>
33 #include <linux/rcupdate.h>
34 #include <linux/capability.h>
35 #include <linux/cpu.h>
36 #include <linux/moduleparam.h>
37 #include <linux/errno.h>
38 #include <linux/err.h>
39 #include <linux/vermagic.h>
40 #include <linux/notifier.h>
41 #include <linux/sched.h>
42 #include <linux/stop_machine.h>
43 #include <linux/device.h>
44 #include <linux/string.h>
45 #include <linux/mutex.h>
46 #include <linux/unwind.h>
47 #include <linux/rculist.h>
48 #include <asm/uaccess.h>
49 #include <asm/cacheflush.h>
50 #include <linux/license.h>
51 #include <asm/sections.h>
52 #include <linux/tracepoint.h>
53 #include <linux/ftrace.h>
55 #if 0
56 #define DEBUGP printk
57 #else
58 #define DEBUGP(fmt , a...)
59 #endif
61 #ifndef ARCH_SHF_SMALL
62 #define ARCH_SHF_SMALL 0
63 #endif
65 /* If this is set, the section belongs in the init part of the module */
66 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
68 /* List of modules, protected by module_mutex or preempt_disable
69 * (delete uses stop_machine/add uses RCU list operations). */
70 static DEFINE_MUTEX(module_mutex);
71 static LIST_HEAD(modules);
73 /* Waiting for a module to finish initializing? */
74 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
76 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
78 /* Bounds of module allocation, for speeding __module_text_address */
79 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
81 int register_module_notifier(struct notifier_block * nb)
83 return blocking_notifier_chain_register(&module_notify_list, nb);
85 EXPORT_SYMBOL(register_module_notifier);
87 int unregister_module_notifier(struct notifier_block * nb)
89 return blocking_notifier_chain_unregister(&module_notify_list, nb);
91 EXPORT_SYMBOL(unregister_module_notifier);
93 /* We require a truly strong try_module_get(): 0 means failure due to
94 ongoing or failed initialization etc. */
95 static inline int strong_try_module_get(struct module *mod)
97 if (mod && mod->state == MODULE_STATE_COMING)
98 return -EBUSY;
99 if (try_module_get(mod))
100 return 0;
101 else
102 return -ENOENT;
105 static inline void add_taint_module(struct module *mod, unsigned flag)
107 add_taint(flag);
108 mod->taints |= (1U << flag);
112 * A thread that wants to hold a reference to a module only while it
113 * is running can call this to safely exit. nfsd and lockd use this.
115 void __module_put_and_exit(struct module *mod, long code)
117 module_put(mod);
118 do_exit(code);
120 EXPORT_SYMBOL(__module_put_and_exit);
122 /* Find a module section: 0 means not found. */
123 static unsigned int find_sec(Elf_Ehdr *hdr,
124 Elf_Shdr *sechdrs,
125 const char *secstrings,
126 const char *name)
128 unsigned int i;
130 for (i = 1; i < hdr->e_shnum; i++)
131 /* Alloc bit cleared means "ignore it." */
132 if ((sechdrs[i].sh_flags & SHF_ALLOC)
133 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
134 return i;
135 return 0;
138 /* Find a module section, or NULL. */
139 static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
140 const char *secstrings, const char *name)
142 /* Section 0 has sh_addr 0. */
143 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
146 /* Find a module section, or NULL. Fill in number of "objects" in section. */
147 static void *section_objs(Elf_Ehdr *hdr,
148 Elf_Shdr *sechdrs,
149 const char *secstrings,
150 const char *name,
151 size_t object_size,
152 unsigned int *num)
154 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
156 /* Section 0 has sh_addr 0 and sh_size 0. */
157 *num = sechdrs[sec].sh_size / object_size;
158 return (void *)sechdrs[sec].sh_addr;
161 /* Provided by the linker */
162 extern const struct kernel_symbol __start___ksymtab[];
163 extern const struct kernel_symbol __stop___ksymtab[];
164 extern const struct kernel_symbol __start___ksymtab_gpl[];
165 extern const struct kernel_symbol __stop___ksymtab_gpl[];
166 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
167 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
168 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
169 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
170 extern const unsigned long __start___kcrctab[];
171 extern const unsigned long __start___kcrctab_gpl[];
172 extern const unsigned long __start___kcrctab_gpl_future[];
173 #ifdef CONFIG_UNUSED_SYMBOLS
174 extern const struct kernel_symbol __start___ksymtab_unused[];
175 extern const struct kernel_symbol __stop___ksymtab_unused[];
176 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
177 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
178 extern const unsigned long __start___kcrctab_unused[];
179 extern const unsigned long __start___kcrctab_unused_gpl[];
180 #endif
182 #ifndef CONFIG_MODVERSIONS
183 #define symversion(base, idx) NULL
184 #else
185 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
186 #endif
188 struct symsearch {
189 const struct kernel_symbol *start, *stop;
190 const unsigned long *crcs;
191 enum {
192 NOT_GPL_ONLY,
193 GPL_ONLY,
194 WILL_BE_GPL_ONLY,
195 } licence;
196 bool unused;
199 static bool each_symbol_in_section(const struct symsearch *arr,
200 unsigned int arrsize,
201 struct module *owner,
202 bool (*fn)(const struct symsearch *syms,
203 struct module *owner,
204 unsigned int symnum, void *data),
205 void *data)
207 unsigned int i, j;
209 for (j = 0; j < arrsize; j++) {
210 for (i = 0; i < arr[j].stop - arr[j].start; i++)
211 if (fn(&arr[j], owner, i, data))
212 return true;
215 return false;
218 /* Returns true as soon as fn returns true, otherwise false. */
219 static bool each_symbol(bool (*fn)(const struct symsearch *arr,
220 struct module *owner,
221 unsigned int symnum, void *data),
222 void *data)
224 struct module *mod;
225 const struct symsearch arr[] = {
226 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
227 NOT_GPL_ONLY, false },
228 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
229 __start___kcrctab_gpl,
230 GPL_ONLY, false },
231 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
232 __start___kcrctab_gpl_future,
233 WILL_BE_GPL_ONLY, false },
234 #ifdef CONFIG_UNUSED_SYMBOLS
235 { __start___ksymtab_unused, __stop___ksymtab_unused,
236 __start___kcrctab_unused,
237 NOT_GPL_ONLY, true },
238 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
239 __start___kcrctab_unused_gpl,
240 GPL_ONLY, true },
241 #endif
244 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
245 return true;
247 list_for_each_entry_rcu(mod, &modules, list) {
248 struct symsearch arr[] = {
249 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
250 NOT_GPL_ONLY, false },
251 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
252 mod->gpl_crcs,
253 GPL_ONLY, false },
254 { mod->gpl_future_syms,
255 mod->gpl_future_syms + mod->num_gpl_future_syms,
256 mod->gpl_future_crcs,
257 WILL_BE_GPL_ONLY, false },
258 #ifdef CONFIG_UNUSED_SYMBOLS
259 { mod->unused_syms,
260 mod->unused_syms + mod->num_unused_syms,
261 mod->unused_crcs,
262 NOT_GPL_ONLY, true },
263 { mod->unused_gpl_syms,
264 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
265 mod->unused_gpl_crcs,
266 GPL_ONLY, true },
267 #endif
270 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
271 return true;
273 return false;
276 struct find_symbol_arg {
277 /* Input */
278 const char *name;
279 bool gplok;
280 bool warn;
282 /* Output */
283 struct module *owner;
284 const unsigned long *crc;
285 unsigned long value;
288 static bool find_symbol_in_section(const struct symsearch *syms,
289 struct module *owner,
290 unsigned int symnum, void *data)
292 struct find_symbol_arg *fsa = data;
294 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
295 return false;
297 if (!fsa->gplok) {
298 if (syms->licence == GPL_ONLY)
299 return false;
300 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
301 printk(KERN_WARNING "Symbol %s is being used "
302 "by a non-GPL module, which will not "
303 "be allowed in the future\n", fsa->name);
304 printk(KERN_WARNING "Please see the file "
305 "Documentation/feature-removal-schedule.txt "
306 "in the kernel source tree for more details.\n");
310 #ifdef CONFIG_UNUSED_SYMBOLS
311 if (syms->unused && fsa->warn) {
312 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
313 "however this module is using it.\n", fsa->name);
314 printk(KERN_WARNING
315 "This symbol will go away in the future.\n");
316 printk(KERN_WARNING
317 "Please evalute if this is the right api to use and if "
318 "it really is, submit a report the linux kernel "
319 "mailinglist together with submitting your code for "
320 "inclusion.\n");
322 #endif
324 fsa->owner = owner;
325 fsa->crc = symversion(syms->crcs, symnum);
326 fsa->value = syms->start[symnum].value;
327 return true;
330 /* Find a symbol, return value, (optional) crc and (optional) module
331 * which owns it */
332 static unsigned long find_symbol(const char *name,
333 struct module **owner,
334 const unsigned long **crc,
335 bool gplok,
336 bool warn)
338 struct find_symbol_arg fsa;
340 fsa.name = name;
341 fsa.gplok = gplok;
342 fsa.warn = warn;
344 if (each_symbol(find_symbol_in_section, &fsa)) {
345 if (owner)
346 *owner = fsa.owner;
347 if (crc)
348 *crc = fsa.crc;
349 return fsa.value;
352 DEBUGP("Failed to find symbol %s\n", name);
353 return -ENOENT;
356 /* Search for module by name: must hold module_mutex. */
357 static struct module *find_module(const char *name)
359 struct module *mod;
361 list_for_each_entry(mod, &modules, list) {
362 if (strcmp(mod->name, name) == 0)
363 return mod;
365 return NULL;
368 #ifdef CONFIG_SMP
369 /* Number of blocks used and allocated. */
370 static unsigned int pcpu_num_used, pcpu_num_allocated;
371 /* Size of each block. -ve means used. */
372 static int *pcpu_size;
374 static int split_block(unsigned int i, unsigned short size)
376 /* Reallocation required? */
377 if (pcpu_num_used + 1 > pcpu_num_allocated) {
378 int *new;
380 new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2,
381 GFP_KERNEL);
382 if (!new)
383 return 0;
385 pcpu_num_allocated *= 2;
386 pcpu_size = new;
389 /* Insert a new subblock */
390 memmove(&pcpu_size[i+1], &pcpu_size[i],
391 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
392 pcpu_num_used++;
394 pcpu_size[i+1] -= size;
395 pcpu_size[i] = size;
396 return 1;
399 static inline unsigned int block_size(int val)
401 if (val < 0)
402 return -val;
403 return val;
406 static void *percpu_modalloc(unsigned long size, unsigned long align,
407 const char *name)
409 unsigned long extra;
410 unsigned int i;
411 void *ptr;
413 if (align > PAGE_SIZE) {
414 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
415 name, align, PAGE_SIZE);
416 align = PAGE_SIZE;
419 ptr = __per_cpu_start;
420 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
421 /* Extra for alignment requirement. */
422 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
423 BUG_ON(i == 0 && extra != 0);
425 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
426 continue;
428 /* Transfer extra to previous block. */
429 if (pcpu_size[i-1] < 0)
430 pcpu_size[i-1] -= extra;
431 else
432 pcpu_size[i-1] += extra;
433 pcpu_size[i] -= extra;
434 ptr += extra;
436 /* Split block if warranted */
437 if (pcpu_size[i] - size > sizeof(unsigned long))
438 if (!split_block(i, size))
439 return NULL;
441 /* Mark allocated */
442 pcpu_size[i] = -pcpu_size[i];
443 return ptr;
446 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
447 size);
448 return NULL;
451 static void percpu_modfree(void *freeme)
453 unsigned int i;
454 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
456 /* First entry is core kernel percpu data. */
457 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
458 if (ptr == freeme) {
459 pcpu_size[i] = -pcpu_size[i];
460 goto free;
463 BUG();
465 free:
466 /* Merge with previous? */
467 if (pcpu_size[i-1] >= 0) {
468 pcpu_size[i-1] += pcpu_size[i];
469 pcpu_num_used--;
470 memmove(&pcpu_size[i], &pcpu_size[i+1],
471 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
472 i--;
474 /* Merge with next? */
475 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
476 pcpu_size[i] += pcpu_size[i+1];
477 pcpu_num_used--;
478 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
479 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
483 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
484 Elf_Shdr *sechdrs,
485 const char *secstrings)
487 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
490 static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
492 int cpu;
494 for_each_possible_cpu(cpu)
495 memcpy(pcpudest + per_cpu_offset(cpu), from, size);
498 static int percpu_modinit(void)
500 pcpu_num_used = 2;
501 pcpu_num_allocated = 2;
502 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
503 GFP_KERNEL);
504 /* Static in-kernel percpu data (used). */
505 pcpu_size[0] = -(__per_cpu_end-__per_cpu_start);
506 /* Free room. */
507 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
508 if (pcpu_size[1] < 0) {
509 printk(KERN_ERR "No per-cpu room for modules.\n");
510 pcpu_num_used = 1;
513 return 0;
515 __initcall(percpu_modinit);
516 #else /* ... !CONFIG_SMP */
517 static inline void *percpu_modalloc(unsigned long size, unsigned long align,
518 const char *name)
520 return NULL;
522 static inline void percpu_modfree(void *pcpuptr)
524 BUG();
526 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
527 Elf_Shdr *sechdrs,
528 const char *secstrings)
530 return 0;
532 static inline void percpu_modcopy(void *pcpudst, const void *src,
533 unsigned long size)
535 /* pcpusec should be 0, and size of that section should be 0. */
536 BUG_ON(size != 0);
538 #endif /* CONFIG_SMP */
540 #define MODINFO_ATTR(field) \
541 static void setup_modinfo_##field(struct module *mod, const char *s) \
543 mod->field = kstrdup(s, GFP_KERNEL); \
545 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
546 struct module *mod, char *buffer) \
548 return sprintf(buffer, "%s\n", mod->field); \
550 static int modinfo_##field##_exists(struct module *mod) \
552 return mod->field != NULL; \
554 static void free_modinfo_##field(struct module *mod) \
556 kfree(mod->field); \
557 mod->field = NULL; \
559 static struct module_attribute modinfo_##field = { \
560 .attr = { .name = __stringify(field), .mode = 0444 }, \
561 .show = show_modinfo_##field, \
562 .setup = setup_modinfo_##field, \
563 .test = modinfo_##field##_exists, \
564 .free = free_modinfo_##field, \
567 MODINFO_ATTR(version);
568 MODINFO_ATTR(srcversion);
570 static char last_unloaded_module[MODULE_NAME_LEN+1];
572 #ifdef CONFIG_MODULE_UNLOAD
573 /* Init the unload section of the module. */
574 static void module_unload_init(struct module *mod)
576 unsigned int i;
578 INIT_LIST_HEAD(&mod->modules_which_use_me);
579 for (i = 0; i < NR_CPUS; i++)
580 local_set(&mod->ref[i].count, 0);
581 /* Hold reference count during initialization. */
582 local_set(&mod->ref[raw_smp_processor_id()].count, 1);
583 /* Backwards compatibility macros put refcount during init. */
584 mod->waiter = current;
587 /* modules using other modules */
588 struct module_use
590 struct list_head list;
591 struct module *module_which_uses;
594 /* Does a already use b? */
595 static int already_uses(struct module *a, struct module *b)
597 struct module_use *use;
599 list_for_each_entry(use, &b->modules_which_use_me, list) {
600 if (use->module_which_uses == a) {
601 DEBUGP("%s uses %s!\n", a->name, b->name);
602 return 1;
605 DEBUGP("%s does not use %s!\n", a->name, b->name);
606 return 0;
609 /* Module a uses b */
610 static int use_module(struct module *a, struct module *b)
612 struct module_use *use;
613 int no_warn, err;
615 if (b == NULL || already_uses(a, b)) return 1;
617 /* If we're interrupted or time out, we fail. */
618 if (wait_event_interruptible_timeout(
619 module_wq, (err = strong_try_module_get(b)) != -EBUSY,
620 30 * HZ) <= 0) {
621 printk("%s: gave up waiting for init of module %s.\n",
622 a->name, b->name);
623 return 0;
626 /* If strong_try_module_get() returned a different error, we fail. */
627 if (err)
628 return 0;
630 DEBUGP("Allocating new usage for %s.\n", a->name);
631 use = kmalloc(sizeof(*use), GFP_ATOMIC);
632 if (!use) {
633 printk("%s: out of memory loading\n", a->name);
634 module_put(b);
635 return 0;
638 use->module_which_uses = a;
639 list_add(&use->list, &b->modules_which_use_me);
640 no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
641 return 1;
644 /* Clear the unload stuff of the module. */
645 static void module_unload_free(struct module *mod)
647 struct module *i;
649 list_for_each_entry(i, &modules, list) {
650 struct module_use *use;
652 list_for_each_entry(use, &i->modules_which_use_me, list) {
653 if (use->module_which_uses == mod) {
654 DEBUGP("%s unusing %s\n", mod->name, i->name);
655 module_put(i);
656 list_del(&use->list);
657 kfree(use);
658 sysfs_remove_link(i->holders_dir, mod->name);
659 /* There can be at most one match. */
660 break;
666 #ifdef CONFIG_MODULE_FORCE_UNLOAD
667 static inline int try_force_unload(unsigned int flags)
669 int ret = (flags & O_TRUNC);
670 if (ret)
671 add_taint(TAINT_FORCED_RMMOD);
672 return ret;
674 #else
675 static inline int try_force_unload(unsigned int flags)
677 return 0;
679 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
681 struct stopref
683 struct module *mod;
684 int flags;
685 int *forced;
688 /* Whole machine is stopped with interrupts off when this runs. */
689 static int __try_stop_module(void *_sref)
691 struct stopref *sref = _sref;
693 /* If it's not unused, quit unless we're forcing. */
694 if (module_refcount(sref->mod) != 0) {
695 if (!(*sref->forced = try_force_unload(sref->flags)))
696 return -EWOULDBLOCK;
699 /* Mark it as dying. */
700 sref->mod->state = MODULE_STATE_GOING;
701 return 0;
704 static int try_stop_module(struct module *mod, int flags, int *forced)
706 if (flags & O_NONBLOCK) {
707 struct stopref sref = { mod, flags, forced };
709 return stop_machine(__try_stop_module, &sref, NULL);
710 } else {
711 /* We don't need to stop the machine for this. */
712 mod->state = MODULE_STATE_GOING;
713 synchronize_sched();
714 return 0;
718 unsigned int module_refcount(struct module *mod)
720 unsigned int i, total = 0;
722 for (i = 0; i < NR_CPUS; i++)
723 total += local_read(&mod->ref[i].count);
724 return total;
726 EXPORT_SYMBOL(module_refcount);
728 /* This exists whether we can unload or not */
729 static void free_module(struct module *mod);
731 static void wait_for_zero_refcount(struct module *mod)
733 /* Since we might sleep for some time, release the mutex first */
734 mutex_unlock(&module_mutex);
735 for (;;) {
736 DEBUGP("Looking at refcount...\n");
737 set_current_state(TASK_UNINTERRUPTIBLE);
738 if (module_refcount(mod) == 0)
739 break;
740 schedule();
742 current->state = TASK_RUNNING;
743 mutex_lock(&module_mutex);
746 asmlinkage long
747 sys_delete_module(const char __user *name_user, unsigned int flags)
749 struct module *mod;
750 char name[MODULE_NAME_LEN];
751 int ret, forced = 0;
753 if (!capable(CAP_SYS_MODULE))
754 return -EPERM;
756 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
757 return -EFAULT;
758 name[MODULE_NAME_LEN-1] = '\0';
760 if (mutex_lock_interruptible(&module_mutex) != 0)
761 return -EINTR;
763 mod = find_module(name);
764 if (!mod) {
765 ret = -ENOENT;
766 goto out;
769 if (!list_empty(&mod->modules_which_use_me)) {
770 /* Other modules depend on us: get rid of them first. */
771 ret = -EWOULDBLOCK;
772 goto out;
775 /* Doing init or already dying? */
776 if (mod->state != MODULE_STATE_LIVE) {
777 /* FIXME: if (force), slam module count and wake up
778 waiter --RR */
779 DEBUGP("%s already dying\n", mod->name);
780 ret = -EBUSY;
781 goto out;
784 /* If it has an init func, it must have an exit func to unload */
785 if (mod->init && !mod->exit) {
786 forced = try_force_unload(flags);
787 if (!forced) {
788 /* This module can't be removed */
789 ret = -EBUSY;
790 goto out;
794 /* Set this up before setting mod->state */
795 mod->waiter = current;
797 /* Stop the machine so refcounts can't move and disable module. */
798 ret = try_stop_module(mod, flags, &forced);
799 if (ret != 0)
800 goto out;
802 /* Never wait if forced. */
803 if (!forced && module_refcount(mod) != 0)
804 wait_for_zero_refcount(mod);
806 mutex_unlock(&module_mutex);
807 /* Final destruction now noone is using it. */
808 if (mod->exit != NULL)
809 mod->exit();
810 blocking_notifier_call_chain(&module_notify_list,
811 MODULE_STATE_GOING, mod);
812 mutex_lock(&module_mutex);
813 /* Store the name of the last unloaded module for diagnostic purposes */
814 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
815 unregister_dynamic_debug_module(mod->name);
816 free_module(mod);
818 out:
819 mutex_unlock(&module_mutex);
820 return ret;
823 static void print_unload_info(struct seq_file *m, struct module *mod)
825 struct module_use *use;
826 int printed_something = 0;
828 seq_printf(m, " %u ", module_refcount(mod));
830 /* Always include a trailing , so userspace can differentiate
831 between this and the old multi-field proc format. */
832 list_for_each_entry(use, &mod->modules_which_use_me, list) {
833 printed_something = 1;
834 seq_printf(m, "%s,", use->module_which_uses->name);
837 if (mod->init != NULL && mod->exit == NULL) {
838 printed_something = 1;
839 seq_printf(m, "[permanent],");
842 if (!printed_something)
843 seq_printf(m, "-");
846 void __symbol_put(const char *symbol)
848 struct module *owner;
850 preempt_disable();
851 if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false)))
852 BUG();
853 module_put(owner);
854 preempt_enable();
856 EXPORT_SYMBOL(__symbol_put);
858 void symbol_put_addr(void *addr)
860 struct module *modaddr;
862 if (core_kernel_text((unsigned long)addr))
863 return;
865 if (!(modaddr = module_text_address((unsigned long)addr)))
866 BUG();
867 module_put(modaddr);
869 EXPORT_SYMBOL_GPL(symbol_put_addr);
871 static ssize_t show_refcnt(struct module_attribute *mattr,
872 struct module *mod, char *buffer)
874 return sprintf(buffer, "%u\n", module_refcount(mod));
877 static struct module_attribute refcnt = {
878 .attr = { .name = "refcnt", .mode = 0444 },
879 .show = show_refcnt,
882 void module_put(struct module *module)
884 if (module) {
885 unsigned int cpu = get_cpu();
886 local_dec(&module->ref[cpu].count);
887 /* Maybe they're waiting for us to drop reference? */
888 if (unlikely(!module_is_live(module)))
889 wake_up_process(module->waiter);
890 put_cpu();
893 EXPORT_SYMBOL(module_put);
895 #else /* !CONFIG_MODULE_UNLOAD */
896 static void print_unload_info(struct seq_file *m, struct module *mod)
898 /* We don't know the usage count, or what modules are using. */
899 seq_printf(m, " - -");
902 static inline void module_unload_free(struct module *mod)
906 static inline int use_module(struct module *a, struct module *b)
908 return strong_try_module_get(b) == 0;
911 static inline void module_unload_init(struct module *mod)
914 #endif /* CONFIG_MODULE_UNLOAD */
916 static ssize_t show_initstate(struct module_attribute *mattr,
917 struct module *mod, char *buffer)
919 const char *state = "unknown";
921 switch (mod->state) {
922 case MODULE_STATE_LIVE:
923 state = "live";
924 break;
925 case MODULE_STATE_COMING:
926 state = "coming";
927 break;
928 case MODULE_STATE_GOING:
929 state = "going";
930 break;
932 return sprintf(buffer, "%s\n", state);
935 static struct module_attribute initstate = {
936 .attr = { .name = "initstate", .mode = 0444 },
937 .show = show_initstate,
940 static struct module_attribute *modinfo_attrs[] = {
941 &modinfo_version,
942 &modinfo_srcversion,
943 &initstate,
944 #ifdef CONFIG_MODULE_UNLOAD
945 &refcnt,
946 #endif
947 NULL,
950 static const char vermagic[] = VERMAGIC_STRING;
952 static int try_to_force_load(struct module *mod, const char *symname)
954 #ifdef CONFIG_MODULE_FORCE_LOAD
955 if (!test_taint(TAINT_FORCED_MODULE))
956 printk("%s: no version for \"%s\" found: kernel tainted.\n",
957 mod->name, symname);
958 add_taint_module(mod, TAINT_FORCED_MODULE);
959 return 0;
960 #else
961 return -ENOEXEC;
962 #endif
965 #ifdef CONFIG_MODVERSIONS
966 static int check_version(Elf_Shdr *sechdrs,
967 unsigned int versindex,
968 const char *symname,
969 struct module *mod,
970 const unsigned long *crc)
972 unsigned int i, num_versions;
973 struct modversion_info *versions;
975 /* Exporting module didn't supply crcs? OK, we're already tainted. */
976 if (!crc)
977 return 1;
979 /* No versions at all? modprobe --force does this. */
980 if (versindex == 0)
981 return try_to_force_load(mod, symname) == 0;
983 versions = (void *) sechdrs[versindex].sh_addr;
984 num_versions = sechdrs[versindex].sh_size
985 / sizeof(struct modversion_info);
987 for (i = 0; i < num_versions; i++) {
988 if (strcmp(versions[i].name, symname) != 0)
989 continue;
991 if (versions[i].crc == *crc)
992 return 1;
993 DEBUGP("Found checksum %lX vs module %lX\n",
994 *crc, versions[i].crc);
995 goto bad_version;
998 printk(KERN_WARNING "%s: no symbol version for %s\n",
999 mod->name, symname);
1000 return 0;
1002 bad_version:
1003 printk("%s: disagrees about version of symbol %s\n",
1004 mod->name, symname);
1005 return 0;
1008 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1009 unsigned int versindex,
1010 struct module *mod)
1012 const unsigned long *crc;
1014 if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false)))
1015 BUG();
1016 return check_version(sechdrs, versindex, "struct_module", mod, crc);
1019 /* First part is kernel version, which we ignore if module has crcs. */
1020 static inline int same_magic(const char *amagic, const char *bmagic,
1021 bool has_crcs)
1023 if (has_crcs) {
1024 amagic += strcspn(amagic, " ");
1025 bmagic += strcspn(bmagic, " ");
1027 return strcmp(amagic, bmagic) == 0;
1029 #else
1030 static inline int check_version(Elf_Shdr *sechdrs,
1031 unsigned int versindex,
1032 const char *symname,
1033 struct module *mod,
1034 const unsigned long *crc)
1036 return 1;
1039 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1040 unsigned int versindex,
1041 struct module *mod)
1043 return 1;
1046 static inline int same_magic(const char *amagic, const char *bmagic,
1047 bool has_crcs)
1049 return strcmp(amagic, bmagic) == 0;
1051 #endif /* CONFIG_MODVERSIONS */
1053 /* Resolve a symbol for this module. I.e. if we find one, record usage.
1054 Must be holding module_mutex. */
1055 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
1056 unsigned int versindex,
1057 const char *name,
1058 struct module *mod)
1060 struct module *owner;
1061 unsigned long ret;
1062 const unsigned long *crc;
1064 ret = find_symbol(name, &owner, &crc,
1065 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1066 if (!IS_ERR_VALUE(ret)) {
1067 /* use_module can fail due to OOM,
1068 or module initialization or unloading */
1069 if (!check_version(sechdrs, versindex, name, mod, crc) ||
1070 !use_module(mod, owner))
1071 ret = -EINVAL;
1073 return ret;
1077 * /sys/module/foo/sections stuff
1078 * J. Corbet <corbet@lwn.net>
1080 #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1081 struct module_sect_attr
1083 struct module_attribute mattr;
1084 char *name;
1085 unsigned long address;
1088 struct module_sect_attrs
1090 struct attribute_group grp;
1091 unsigned int nsections;
1092 struct module_sect_attr attrs[0];
1095 static ssize_t module_sect_show(struct module_attribute *mattr,
1096 struct module *mod, char *buf)
1098 struct module_sect_attr *sattr =
1099 container_of(mattr, struct module_sect_attr, mattr);
1100 return sprintf(buf, "0x%lx\n", sattr->address);
1103 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1105 unsigned int section;
1107 for (section = 0; section < sect_attrs->nsections; section++)
1108 kfree(sect_attrs->attrs[section].name);
1109 kfree(sect_attrs);
1112 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1113 char *secstrings, Elf_Shdr *sechdrs)
1115 unsigned int nloaded = 0, i, size[2];
1116 struct module_sect_attrs *sect_attrs;
1117 struct module_sect_attr *sattr;
1118 struct attribute **gattr;
1120 /* Count loaded sections and allocate structures */
1121 for (i = 0; i < nsect; i++)
1122 if (sechdrs[i].sh_flags & SHF_ALLOC)
1123 nloaded++;
1124 size[0] = ALIGN(sizeof(*sect_attrs)
1125 + nloaded * sizeof(sect_attrs->attrs[0]),
1126 sizeof(sect_attrs->grp.attrs[0]));
1127 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1128 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1129 if (sect_attrs == NULL)
1130 return;
1132 /* Setup section attributes. */
1133 sect_attrs->grp.name = "sections";
1134 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1136 sect_attrs->nsections = 0;
1137 sattr = &sect_attrs->attrs[0];
1138 gattr = &sect_attrs->grp.attrs[0];
1139 for (i = 0; i < nsect; i++) {
1140 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1141 continue;
1142 sattr->address = sechdrs[i].sh_addr;
1143 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1144 GFP_KERNEL);
1145 if (sattr->name == NULL)
1146 goto out;
1147 sect_attrs->nsections++;
1148 sattr->mattr.show = module_sect_show;
1149 sattr->mattr.store = NULL;
1150 sattr->mattr.attr.name = sattr->name;
1151 sattr->mattr.attr.mode = S_IRUGO;
1152 *(gattr++) = &(sattr++)->mattr.attr;
1154 *gattr = NULL;
1156 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1157 goto out;
1159 mod->sect_attrs = sect_attrs;
1160 return;
1161 out:
1162 free_sect_attrs(sect_attrs);
1165 static void remove_sect_attrs(struct module *mod)
1167 if (mod->sect_attrs) {
1168 sysfs_remove_group(&mod->mkobj.kobj,
1169 &mod->sect_attrs->grp);
1170 /* We are positive that no one is using any sect attrs
1171 * at this point. Deallocate immediately. */
1172 free_sect_attrs(mod->sect_attrs);
1173 mod->sect_attrs = NULL;
1178 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1181 struct module_notes_attrs {
1182 struct kobject *dir;
1183 unsigned int notes;
1184 struct bin_attribute attrs[0];
1187 static ssize_t module_notes_read(struct kobject *kobj,
1188 struct bin_attribute *bin_attr,
1189 char *buf, loff_t pos, size_t count)
1192 * The caller checked the pos and count against our size.
1194 memcpy(buf, bin_attr->private + pos, count);
1195 return count;
1198 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1199 unsigned int i)
1201 if (notes_attrs->dir) {
1202 while (i-- > 0)
1203 sysfs_remove_bin_file(notes_attrs->dir,
1204 &notes_attrs->attrs[i]);
1205 kobject_put(notes_attrs->dir);
1207 kfree(notes_attrs);
1210 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1211 char *secstrings, Elf_Shdr *sechdrs)
1213 unsigned int notes, loaded, i;
1214 struct module_notes_attrs *notes_attrs;
1215 struct bin_attribute *nattr;
1217 /* Count notes sections and allocate structures. */
1218 notes = 0;
1219 for (i = 0; i < nsect; i++)
1220 if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
1221 (sechdrs[i].sh_type == SHT_NOTE))
1222 ++notes;
1224 if (notes == 0)
1225 return;
1227 notes_attrs = kzalloc(sizeof(*notes_attrs)
1228 + notes * sizeof(notes_attrs->attrs[0]),
1229 GFP_KERNEL);
1230 if (notes_attrs == NULL)
1231 return;
1233 notes_attrs->notes = notes;
1234 nattr = &notes_attrs->attrs[0];
1235 for (loaded = i = 0; i < nsect; ++i) {
1236 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1237 continue;
1238 if (sechdrs[i].sh_type == SHT_NOTE) {
1239 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1240 nattr->attr.mode = S_IRUGO;
1241 nattr->size = sechdrs[i].sh_size;
1242 nattr->private = (void *) sechdrs[i].sh_addr;
1243 nattr->read = module_notes_read;
1244 ++nattr;
1246 ++loaded;
1249 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1250 if (!notes_attrs->dir)
1251 goto out;
1253 for (i = 0; i < notes; ++i)
1254 if (sysfs_create_bin_file(notes_attrs->dir,
1255 &notes_attrs->attrs[i]))
1256 goto out;
1258 mod->notes_attrs = notes_attrs;
1259 return;
1261 out:
1262 free_notes_attrs(notes_attrs, i);
1265 static void remove_notes_attrs(struct module *mod)
1267 if (mod->notes_attrs)
1268 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1271 #else
1273 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1274 char *sectstrings, Elf_Shdr *sechdrs)
1278 static inline void remove_sect_attrs(struct module *mod)
1282 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1283 char *sectstrings, Elf_Shdr *sechdrs)
1287 static inline void remove_notes_attrs(struct module *mod)
1290 #endif
1292 #ifdef CONFIG_SYSFS
1293 int module_add_modinfo_attrs(struct module *mod)
1295 struct module_attribute *attr;
1296 struct module_attribute *temp_attr;
1297 int error = 0;
1298 int i;
1300 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1301 (ARRAY_SIZE(modinfo_attrs) + 1)),
1302 GFP_KERNEL);
1303 if (!mod->modinfo_attrs)
1304 return -ENOMEM;
1306 temp_attr = mod->modinfo_attrs;
1307 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1308 if (!attr->test ||
1309 (attr->test && attr->test(mod))) {
1310 memcpy(temp_attr, attr, sizeof(*temp_attr));
1311 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1312 ++temp_attr;
1315 return error;
1318 void module_remove_modinfo_attrs(struct module *mod)
1320 struct module_attribute *attr;
1321 int i;
1323 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1324 /* pick a field to test for end of list */
1325 if (!attr->attr.name)
1326 break;
1327 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1328 if (attr->free)
1329 attr->free(mod);
1331 kfree(mod->modinfo_attrs);
1334 int mod_sysfs_init(struct module *mod)
1336 int err;
1337 struct kobject *kobj;
1339 if (!module_sysfs_initialized) {
1340 printk(KERN_ERR "%s: module sysfs not initialized\n",
1341 mod->name);
1342 err = -EINVAL;
1343 goto out;
1346 kobj = kset_find_obj(module_kset, mod->name);
1347 if (kobj) {
1348 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1349 kobject_put(kobj);
1350 err = -EINVAL;
1351 goto out;
1354 mod->mkobj.mod = mod;
1356 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1357 mod->mkobj.kobj.kset = module_kset;
1358 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1359 "%s", mod->name);
1360 if (err)
1361 kobject_put(&mod->mkobj.kobj);
1363 /* delay uevent until full sysfs population */
1364 out:
1365 return err;
1368 int mod_sysfs_setup(struct module *mod,
1369 struct kernel_param *kparam,
1370 unsigned int num_params)
1372 int err;
1374 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1375 if (!mod->holders_dir) {
1376 err = -ENOMEM;
1377 goto out_unreg;
1380 err = module_param_sysfs_setup(mod, kparam, num_params);
1381 if (err)
1382 goto out_unreg_holders;
1384 err = module_add_modinfo_attrs(mod);
1385 if (err)
1386 goto out_unreg_param;
1388 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1389 return 0;
1391 out_unreg_param:
1392 module_param_sysfs_remove(mod);
1393 out_unreg_holders:
1394 kobject_put(mod->holders_dir);
1395 out_unreg:
1396 kobject_put(&mod->mkobj.kobj);
1397 return err;
1400 static void mod_sysfs_fini(struct module *mod)
1402 kobject_put(&mod->mkobj.kobj);
1405 #else /* CONFIG_SYSFS */
1407 static void mod_sysfs_fini(struct module *mod)
1411 #endif /* CONFIG_SYSFS */
1413 static void mod_kobject_remove(struct module *mod)
1415 module_remove_modinfo_attrs(mod);
1416 module_param_sysfs_remove(mod);
1417 kobject_put(mod->mkobj.drivers_dir);
1418 kobject_put(mod->holders_dir);
1419 mod_sysfs_fini(mod);
1423 * unlink the module with the whole machine is stopped with interrupts off
1424 * - this defends against kallsyms not taking locks
1426 static int __unlink_module(void *_mod)
1428 struct module *mod = _mod;
1429 list_del(&mod->list);
1430 return 0;
1433 /* Free a module, remove from lists, etc (must hold module_mutex). */
1434 static void free_module(struct module *mod)
1436 /* Delete from various lists */
1437 stop_machine(__unlink_module, mod, NULL);
1438 remove_notes_attrs(mod);
1439 remove_sect_attrs(mod);
1440 mod_kobject_remove(mod);
1442 unwind_remove_table(mod->unwind_info, 0);
1444 /* Arch-specific cleanup. */
1445 module_arch_cleanup(mod);
1447 /* Module unload stuff */
1448 module_unload_free(mod);
1450 /* release any pointers to mcount in this module */
1451 ftrace_release(mod->module_core, mod->core_size);
1453 /* This may be NULL, but that's OK */
1454 module_free(mod, mod->module_init);
1455 kfree(mod->args);
1456 if (mod->percpu)
1457 percpu_modfree(mod->percpu);
1459 /* Free lock-classes: */
1460 lockdep_free_key_range(mod->module_core, mod->core_size);
1462 /* Finally, free the core (containing the module structure) */
1463 module_free(mod, mod->module_core);
1466 void *__symbol_get(const char *symbol)
1468 struct module *owner;
1469 unsigned long value;
1471 preempt_disable();
1472 value = find_symbol(symbol, &owner, NULL, true, true);
1473 if (IS_ERR_VALUE(value))
1474 value = 0;
1475 else if (strong_try_module_get(owner))
1476 value = 0;
1477 preempt_enable();
1479 return (void *)value;
1481 EXPORT_SYMBOL_GPL(__symbol_get);
1484 * Ensure that an exported symbol [global namespace] does not already exist
1485 * in the kernel or in some other module's exported symbol table.
1487 static int verify_export_symbols(struct module *mod)
1489 unsigned int i;
1490 struct module *owner;
1491 const struct kernel_symbol *s;
1492 struct {
1493 const struct kernel_symbol *sym;
1494 unsigned int num;
1495 } arr[] = {
1496 { mod->syms, mod->num_syms },
1497 { mod->gpl_syms, mod->num_gpl_syms },
1498 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1499 #ifdef CONFIG_UNUSED_SYMBOLS
1500 { mod->unused_syms, mod->num_unused_syms },
1501 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1502 #endif
1505 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1506 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1507 if (!IS_ERR_VALUE(find_symbol(s->name, &owner,
1508 NULL, true, false))) {
1509 printk(KERN_ERR
1510 "%s: exports duplicate symbol %s"
1511 " (owned by %s)\n",
1512 mod->name, s->name, module_name(owner));
1513 return -ENOEXEC;
1517 return 0;
1520 /* Change all symbols so that st_value encodes the pointer directly. */
1521 static int simplify_symbols(Elf_Shdr *sechdrs,
1522 unsigned int symindex,
1523 const char *strtab,
1524 unsigned int versindex,
1525 unsigned int pcpuindex,
1526 struct module *mod)
1528 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1529 unsigned long secbase;
1530 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1531 int ret = 0;
1533 for (i = 1; i < n; i++) {
1534 switch (sym[i].st_shndx) {
1535 case SHN_COMMON:
1536 /* We compiled with -fno-common. These are not
1537 supposed to happen. */
1538 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1539 printk("%s: please compile with -fno-common\n",
1540 mod->name);
1541 ret = -ENOEXEC;
1542 break;
1544 case SHN_ABS:
1545 /* Don't need to do anything */
1546 DEBUGP("Absolute symbol: 0x%08lx\n",
1547 (long)sym[i].st_value);
1548 break;
1550 case SHN_UNDEF:
1551 sym[i].st_value
1552 = resolve_symbol(sechdrs, versindex,
1553 strtab + sym[i].st_name, mod);
1555 /* Ok if resolved. */
1556 if (!IS_ERR_VALUE(sym[i].st_value))
1557 break;
1558 /* Ok if weak. */
1559 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1560 break;
1562 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1563 mod->name, strtab + sym[i].st_name);
1564 ret = -ENOENT;
1565 break;
1567 default:
1568 /* Divert to percpu allocation if a percpu var. */
1569 if (sym[i].st_shndx == pcpuindex)
1570 secbase = (unsigned long)mod->percpu;
1571 else
1572 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1573 sym[i].st_value += secbase;
1574 break;
1578 return ret;
1581 /* Update size with this section: return offset. */
1582 static long get_offset(unsigned int *size, Elf_Shdr *sechdr)
1584 long ret;
1586 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1587 *size = ret + sechdr->sh_size;
1588 return ret;
1591 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1592 might -- code, read-only data, read-write data, small data. Tally
1593 sizes, and place the offsets into sh_entsize fields: high bit means it
1594 belongs in init. */
1595 static void layout_sections(struct module *mod,
1596 const Elf_Ehdr *hdr,
1597 Elf_Shdr *sechdrs,
1598 const char *secstrings)
1600 static unsigned long const masks[][2] = {
1601 /* NOTE: all executable code must be the first section
1602 * in this array; otherwise modify the text_size
1603 * finder in the two loops below */
1604 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1605 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1606 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1607 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1609 unsigned int m, i;
1611 for (i = 0; i < hdr->e_shnum; i++)
1612 sechdrs[i].sh_entsize = ~0UL;
1614 DEBUGP("Core section allocation order:\n");
1615 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1616 for (i = 0; i < hdr->e_shnum; ++i) {
1617 Elf_Shdr *s = &sechdrs[i];
1619 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1620 || (s->sh_flags & masks[m][1])
1621 || s->sh_entsize != ~0UL
1622 || strncmp(secstrings + s->sh_name,
1623 ".init", 5) == 0)
1624 continue;
1625 s->sh_entsize = get_offset(&mod->core_size, s);
1626 DEBUGP("\t%s\n", secstrings + s->sh_name);
1628 if (m == 0)
1629 mod->core_text_size = mod->core_size;
1632 DEBUGP("Init section allocation order:\n");
1633 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1634 for (i = 0; i < hdr->e_shnum; ++i) {
1635 Elf_Shdr *s = &sechdrs[i];
1637 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1638 || (s->sh_flags & masks[m][1])
1639 || s->sh_entsize != ~0UL
1640 || strncmp(secstrings + s->sh_name,
1641 ".init", 5) != 0)
1642 continue;
1643 s->sh_entsize = (get_offset(&mod->init_size, s)
1644 | INIT_OFFSET_MASK);
1645 DEBUGP("\t%s\n", secstrings + s->sh_name);
1647 if (m == 0)
1648 mod->init_text_size = mod->init_size;
1652 static void set_license(struct module *mod, const char *license)
1654 if (!license)
1655 license = "unspecified";
1657 if (!license_is_gpl_compatible(license)) {
1658 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1659 printk(KERN_WARNING "%s: module license '%s' taints "
1660 "kernel.\n", mod->name, license);
1661 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1665 /* Parse tag=value strings from .modinfo section */
1666 static char *next_string(char *string, unsigned long *secsize)
1668 /* Skip non-zero chars */
1669 while (string[0]) {
1670 string++;
1671 if ((*secsize)-- <= 1)
1672 return NULL;
1675 /* Skip any zero padding. */
1676 while (!string[0]) {
1677 string++;
1678 if ((*secsize)-- <= 1)
1679 return NULL;
1681 return string;
1684 static char *get_modinfo(Elf_Shdr *sechdrs,
1685 unsigned int info,
1686 const char *tag)
1688 char *p;
1689 unsigned int taglen = strlen(tag);
1690 unsigned long size = sechdrs[info].sh_size;
1692 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1693 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1694 return p + taglen + 1;
1696 return NULL;
1699 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1700 unsigned int infoindex)
1702 struct module_attribute *attr;
1703 int i;
1705 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1706 if (attr->setup)
1707 attr->setup(mod,
1708 get_modinfo(sechdrs,
1709 infoindex,
1710 attr->attr.name));
1714 #ifdef CONFIG_KALLSYMS
1716 /* lookup symbol in given range of kernel_symbols */
1717 static const struct kernel_symbol *lookup_symbol(const char *name,
1718 const struct kernel_symbol *start,
1719 const struct kernel_symbol *stop)
1721 const struct kernel_symbol *ks = start;
1722 for (; ks < stop; ks++)
1723 if (strcmp(ks->name, name) == 0)
1724 return ks;
1725 return NULL;
1728 static int is_exported(const char *name, const struct module *mod)
1730 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1731 return 1;
1732 else
1733 if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1734 return 1;
1735 else
1736 return 0;
1739 /* As per nm */
1740 static char elf_type(const Elf_Sym *sym,
1741 Elf_Shdr *sechdrs,
1742 const char *secstrings,
1743 struct module *mod)
1745 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1746 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1747 return 'v';
1748 else
1749 return 'w';
1751 if (sym->st_shndx == SHN_UNDEF)
1752 return 'U';
1753 if (sym->st_shndx == SHN_ABS)
1754 return 'a';
1755 if (sym->st_shndx >= SHN_LORESERVE)
1756 return '?';
1757 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1758 return 't';
1759 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1760 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1761 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1762 return 'r';
1763 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1764 return 'g';
1765 else
1766 return 'd';
1768 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1769 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1770 return 's';
1771 else
1772 return 'b';
1774 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1775 ".debug", strlen(".debug")) == 0)
1776 return 'n';
1777 return '?';
1780 static void add_kallsyms(struct module *mod,
1781 Elf_Shdr *sechdrs,
1782 unsigned int symindex,
1783 unsigned int strindex,
1784 const char *secstrings)
1786 unsigned int i;
1788 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1789 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1790 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1792 /* Set types up while we still have access to sections. */
1793 for (i = 0; i < mod->num_symtab; i++)
1794 mod->symtab[i].st_info
1795 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1797 #else
1798 static inline void add_kallsyms(struct module *mod,
1799 Elf_Shdr *sechdrs,
1800 unsigned int symindex,
1801 unsigned int strindex,
1802 const char *secstrings)
1805 #endif /* CONFIG_KALLSYMS */
1807 static void dynamic_printk_setup(struct mod_debug *debug, unsigned int num)
1809 #ifdef CONFIG_DYNAMIC_PRINTK_DEBUG
1810 unsigned int i;
1812 for (i = 0; i < num; i++) {
1813 register_dynamic_debug_module(debug[i].modname,
1814 debug[i].type,
1815 debug[i].logical_modname,
1816 debug[i].flag_names,
1817 debug[i].hash, debug[i].hash2);
1819 #endif /* CONFIG_DYNAMIC_PRINTK_DEBUG */
1822 static void *module_alloc_update_bounds(unsigned long size)
1824 void *ret = module_alloc(size);
1826 if (ret) {
1827 /* Update module bounds. */
1828 if ((unsigned long)ret < module_addr_min)
1829 module_addr_min = (unsigned long)ret;
1830 if ((unsigned long)ret + size > module_addr_max)
1831 module_addr_max = (unsigned long)ret + size;
1833 return ret;
1836 /* Allocate and load the module: note that size of section 0 is always
1837 zero, and we rely on this for optional sections. */
1838 static noinline struct module *load_module(void __user *umod,
1839 unsigned long len,
1840 const char __user *uargs)
1842 Elf_Ehdr *hdr;
1843 Elf_Shdr *sechdrs;
1844 char *secstrings, *args, *modmagic, *strtab = NULL;
1845 char *staging;
1846 unsigned int i;
1847 unsigned int symindex = 0;
1848 unsigned int strindex = 0;
1849 unsigned int modindex, versindex, infoindex, pcpuindex;
1850 unsigned int unwindex = 0;
1851 unsigned int num_kp, num_mcount;
1852 struct kernel_param *kp;
1853 struct module *mod;
1854 long err = 0;
1855 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1856 unsigned long *mseg;
1857 mm_segment_t old_fs;
1859 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1860 umod, len, uargs);
1861 if (len < sizeof(*hdr))
1862 return ERR_PTR(-ENOEXEC);
1864 /* Suck in entire file: we'll want most of it. */
1865 /* vmalloc barfs on "unusual" numbers. Check here */
1866 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1867 return ERR_PTR(-ENOMEM);
1868 if (copy_from_user(hdr, umod, len) != 0) {
1869 err = -EFAULT;
1870 goto free_hdr;
1873 /* Sanity checks against insmoding binaries or wrong arch,
1874 weird elf version */
1875 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
1876 || hdr->e_type != ET_REL
1877 || !elf_check_arch(hdr)
1878 || hdr->e_shentsize != sizeof(*sechdrs)) {
1879 err = -ENOEXEC;
1880 goto free_hdr;
1883 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1884 goto truncated;
1886 /* Convenience variables */
1887 sechdrs = (void *)hdr + hdr->e_shoff;
1888 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1889 sechdrs[0].sh_addr = 0;
1891 for (i = 1; i < hdr->e_shnum; i++) {
1892 if (sechdrs[i].sh_type != SHT_NOBITS
1893 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1894 goto truncated;
1896 /* Mark all sections sh_addr with their address in the
1897 temporary image. */
1898 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1900 /* Internal symbols and strings. */
1901 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1902 symindex = i;
1903 strindex = sechdrs[i].sh_link;
1904 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1906 #ifndef CONFIG_MODULE_UNLOAD
1907 /* Don't load .exit sections */
1908 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1909 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1910 #endif
1913 modindex = find_sec(hdr, sechdrs, secstrings,
1914 ".gnu.linkonce.this_module");
1915 if (!modindex) {
1916 printk(KERN_WARNING "No module found in object\n");
1917 err = -ENOEXEC;
1918 goto free_hdr;
1920 /* This is temporary: point mod into copy of data. */
1921 mod = (void *)sechdrs[modindex].sh_addr;
1923 if (symindex == 0) {
1924 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1925 mod->name);
1926 err = -ENOEXEC;
1927 goto free_hdr;
1930 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1931 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1932 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1933 #ifdef ARCH_UNWIND_SECTION_NAME
1934 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1935 #endif
1937 /* Don't keep modinfo and version sections. */
1938 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1939 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1940 #ifdef CONFIG_KALLSYMS
1941 /* Keep symbol and string tables for decoding later. */
1942 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1943 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1944 #endif
1945 if (unwindex)
1946 sechdrs[unwindex].sh_flags |= SHF_ALLOC;
1948 /* Check module struct version now, before we try to use module. */
1949 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1950 err = -ENOEXEC;
1951 goto free_hdr;
1954 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1955 /* This is allowed: modprobe --force will invalidate it. */
1956 if (!modmagic) {
1957 err = try_to_force_load(mod, "magic");
1958 if (err)
1959 goto free_hdr;
1960 } else if (!same_magic(modmagic, vermagic, versindex)) {
1961 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1962 mod->name, modmagic, vermagic);
1963 err = -ENOEXEC;
1964 goto free_hdr;
1967 staging = get_modinfo(sechdrs, infoindex, "staging");
1968 if (staging) {
1969 add_taint_module(mod, TAINT_CRAP);
1970 printk(KERN_WARNING "%s: module is from the staging directory,"
1971 " the quality is unknown, you have been warned.\n",
1972 mod->name);
1975 /* Now copy in args */
1976 args = strndup_user(uargs, ~0UL >> 1);
1977 if (IS_ERR(args)) {
1978 err = PTR_ERR(args);
1979 goto free_hdr;
1982 if (find_module(mod->name)) {
1983 err = -EEXIST;
1984 goto free_mod;
1987 mod->state = MODULE_STATE_COMING;
1989 /* Allow arches to frob section contents and sizes. */
1990 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1991 if (err < 0)
1992 goto free_mod;
1994 if (pcpuindex) {
1995 /* We have a special allocation for this section. */
1996 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1997 sechdrs[pcpuindex].sh_addralign,
1998 mod->name);
1999 if (!percpu) {
2000 err = -ENOMEM;
2001 goto free_mod;
2003 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2004 mod->percpu = percpu;
2007 /* Determine total sizes, and put offsets in sh_entsize. For now
2008 this is done generically; there doesn't appear to be any
2009 special cases for the architectures. */
2010 layout_sections(mod, hdr, sechdrs, secstrings);
2012 /* Do the allocs. */
2013 ptr = module_alloc_update_bounds(mod->core_size);
2014 if (!ptr) {
2015 err = -ENOMEM;
2016 goto free_percpu;
2018 memset(ptr, 0, mod->core_size);
2019 mod->module_core = ptr;
2021 ptr = module_alloc_update_bounds(mod->init_size);
2022 if (!ptr && mod->init_size) {
2023 err = -ENOMEM;
2024 goto free_core;
2026 memset(ptr, 0, mod->init_size);
2027 mod->module_init = ptr;
2029 /* Transfer each section which specifies SHF_ALLOC */
2030 DEBUGP("final section addresses:\n");
2031 for (i = 0; i < hdr->e_shnum; i++) {
2032 void *dest;
2034 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2035 continue;
2037 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2038 dest = mod->module_init
2039 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2040 else
2041 dest = mod->module_core + sechdrs[i].sh_entsize;
2043 if (sechdrs[i].sh_type != SHT_NOBITS)
2044 memcpy(dest, (void *)sechdrs[i].sh_addr,
2045 sechdrs[i].sh_size);
2046 /* Update sh_addr to point to copy in image. */
2047 sechdrs[i].sh_addr = (unsigned long)dest;
2048 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2050 /* Module has been moved. */
2051 mod = (void *)sechdrs[modindex].sh_addr;
2053 /* Now we've moved module, initialize linked lists, etc. */
2054 module_unload_init(mod);
2056 /* add kobject, so we can reference it. */
2057 err = mod_sysfs_init(mod);
2058 if (err)
2059 goto free_unload;
2061 /* Set up license info based on the info section */
2062 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2065 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2066 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2067 * using GPL-only symbols it needs.
2069 if (strcmp(mod->name, "ndiswrapper") == 0)
2070 add_taint(TAINT_PROPRIETARY_MODULE);
2072 /* driverloader was caught wrongly pretending to be under GPL */
2073 if (strcmp(mod->name, "driverloader") == 0)
2074 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2076 /* Set up MODINFO_ATTR fields */
2077 setup_modinfo(mod, sechdrs, infoindex);
2079 /* Fix up syms, so that st_value is a pointer to location. */
2080 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2081 mod);
2082 if (err < 0)
2083 goto cleanup;
2085 /* Now we've got everything in the final locations, we can
2086 * find optional sections. */
2087 kp = section_objs(hdr, sechdrs, secstrings, "__param", sizeof(*kp),
2088 &num_kp);
2089 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2090 sizeof(*mod->syms), &mod->num_syms);
2091 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2092 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2093 sizeof(*mod->gpl_syms),
2094 &mod->num_gpl_syms);
2095 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2096 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2097 "__ksymtab_gpl_future",
2098 sizeof(*mod->gpl_future_syms),
2099 &mod->num_gpl_future_syms);
2100 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2101 "__kcrctab_gpl_future");
2103 #ifdef CONFIG_UNUSED_SYMBOLS
2104 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2105 "__ksymtab_unused",
2106 sizeof(*mod->unused_syms),
2107 &mod->num_unused_syms);
2108 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2109 "__kcrctab_unused");
2110 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2111 "__ksymtab_unused_gpl",
2112 sizeof(*mod->unused_gpl_syms),
2113 &mod->num_unused_gpl_syms);
2114 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2115 "__kcrctab_unused_gpl");
2116 #endif
2118 #ifdef CONFIG_MARKERS
2119 mod->markers = section_objs(hdr, sechdrs, secstrings, "__markers",
2120 sizeof(*mod->markers), &mod->num_markers);
2121 #endif
2122 #ifdef CONFIG_TRACEPOINTS
2123 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2124 "__tracepoints",
2125 sizeof(*mod->tracepoints),
2126 &mod->num_tracepoints);
2127 #endif
2129 #ifdef CONFIG_MODVERSIONS
2130 if ((mod->num_syms && !mod->crcs)
2131 || (mod->num_gpl_syms && !mod->gpl_crcs)
2132 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2133 #ifdef CONFIG_UNUSED_SYMBOLS
2134 || (mod->num_unused_syms && !mod->unused_crcs)
2135 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2136 #endif
2138 printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name);
2139 err = try_to_force_load(mod, "nocrc");
2140 if (err)
2141 goto cleanup;
2143 #endif
2145 /* Now do relocations. */
2146 for (i = 1; i < hdr->e_shnum; i++) {
2147 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2148 unsigned int info = sechdrs[i].sh_info;
2150 /* Not a valid relocation section? */
2151 if (info >= hdr->e_shnum)
2152 continue;
2154 /* Don't bother with non-allocated sections */
2155 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2156 continue;
2158 if (sechdrs[i].sh_type == SHT_REL)
2159 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2160 else if (sechdrs[i].sh_type == SHT_RELA)
2161 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2162 mod);
2163 if (err < 0)
2164 goto cleanup;
2167 /* Find duplicate symbols */
2168 err = verify_export_symbols(mod);
2169 if (err < 0)
2170 goto cleanup;
2172 /* Set up and sort exception table */
2173 mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
2174 sizeof(*mod->extable), &mod->num_exentries);
2175 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2177 /* Finally, copy percpu area over. */
2178 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
2179 sechdrs[pcpuindex].sh_size);
2181 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
2183 if (!mod->taints) {
2184 struct mod_debug *debug;
2185 unsigned int num_debug;
2187 #ifdef CONFIG_MARKERS
2188 marker_update_probe_range(mod->markers,
2189 mod->markers + mod->num_markers);
2190 #endif
2191 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2192 sizeof(*debug), &num_debug);
2193 dynamic_printk_setup(debug, num_debug);
2195 #ifdef CONFIG_TRACEPOINTS
2196 tracepoint_update_probe_range(mod->tracepoints,
2197 mod->tracepoints + mod->num_tracepoints);
2198 #endif
2201 /* sechdrs[0].sh_size is always zero */
2202 mseg = section_objs(hdr, sechdrs, secstrings, "__mcount_loc",
2203 sizeof(*mseg), &num_mcount);
2204 ftrace_init_module(mseg, mseg + num_mcount);
2206 err = module_finalize(hdr, sechdrs, mod);
2207 if (err < 0)
2208 goto cleanup;
2210 /* flush the icache in correct context */
2211 old_fs = get_fs();
2212 set_fs(KERNEL_DS);
2215 * Flush the instruction cache, since we've played with text.
2216 * Do it before processing of module parameters, so the module
2217 * can provide parameter accessor functions of its own.
2219 if (mod->module_init)
2220 flush_icache_range((unsigned long)mod->module_init,
2221 (unsigned long)mod->module_init
2222 + mod->init_size);
2223 flush_icache_range((unsigned long)mod->module_core,
2224 (unsigned long)mod->module_core + mod->core_size);
2226 set_fs(old_fs);
2228 mod->args = args;
2229 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2230 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2231 mod->name);
2233 /* Now sew it into the lists so we can get lockdep and oops
2234 * info during argument parsing. Noone should access us, since
2235 * strong_try_module_get() will fail.
2236 * lockdep/oops can run asynchronous, so use the RCU list insertion
2237 * function to insert in a way safe to concurrent readers.
2238 * The mutex protects against concurrent writers.
2240 list_add_rcu(&mod->list, &modules);
2242 err = parse_args(mod->name, mod->args, kp, num_kp, NULL);
2243 if (err < 0)
2244 goto unlink;
2246 err = mod_sysfs_setup(mod, kp, num_kp);
2247 if (err < 0)
2248 goto unlink;
2249 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2250 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2252 /* Size of section 0 is 0, so this works well if no unwind info. */
2253 mod->unwind_info = unwind_add_table(mod,
2254 (void *)sechdrs[unwindex].sh_addr,
2255 sechdrs[unwindex].sh_size);
2257 /* Get rid of temporary copy */
2258 vfree(hdr);
2260 /* Done! */
2261 return mod;
2263 unlink:
2264 stop_machine(__unlink_module, mod, NULL);
2265 module_arch_cleanup(mod);
2266 cleanup:
2267 kobject_del(&mod->mkobj.kobj);
2268 kobject_put(&mod->mkobj.kobj);
2269 ftrace_release(mod->module_core, mod->core_size);
2270 free_unload:
2271 module_unload_free(mod);
2272 module_free(mod, mod->module_init);
2273 free_core:
2274 module_free(mod, mod->module_core);
2275 free_percpu:
2276 if (percpu)
2277 percpu_modfree(percpu);
2278 free_mod:
2279 kfree(args);
2280 free_hdr:
2281 vfree(hdr);
2282 return ERR_PTR(err);
2284 truncated:
2285 printk(KERN_ERR "Module len %lu truncated\n", len);
2286 err = -ENOEXEC;
2287 goto free_hdr;
2290 /* This is where the real work happens */
2291 asmlinkage long
2292 sys_init_module(void __user *umod,
2293 unsigned long len,
2294 const char __user *uargs)
2296 struct module *mod;
2297 int ret = 0;
2299 /* Must have permission */
2300 if (!capable(CAP_SYS_MODULE))
2301 return -EPERM;
2303 /* Only one module load at a time, please */
2304 if (mutex_lock_interruptible(&module_mutex) != 0)
2305 return -EINTR;
2307 /* Do all the hard work */
2308 mod = load_module(umod, len, uargs);
2309 if (IS_ERR(mod)) {
2310 mutex_unlock(&module_mutex);
2311 return PTR_ERR(mod);
2314 /* Drop lock so they can recurse */
2315 mutex_unlock(&module_mutex);
2317 blocking_notifier_call_chain(&module_notify_list,
2318 MODULE_STATE_COMING, mod);
2320 /* Start the module */
2321 if (mod->init != NULL)
2322 ret = do_one_initcall(mod->init);
2323 if (ret < 0) {
2324 /* Init routine failed: abort. Try to protect us from
2325 buggy refcounters. */
2326 mod->state = MODULE_STATE_GOING;
2327 synchronize_sched();
2328 module_put(mod);
2329 blocking_notifier_call_chain(&module_notify_list,
2330 MODULE_STATE_GOING, mod);
2331 mutex_lock(&module_mutex);
2332 free_module(mod);
2333 mutex_unlock(&module_mutex);
2334 wake_up(&module_wq);
2335 return ret;
2337 if (ret > 0) {
2338 printk(KERN_WARNING "%s: '%s'->init suspiciously returned %d, "
2339 "it should follow 0/-E convention\n"
2340 KERN_WARNING "%s: loading module anyway...\n",
2341 __func__, mod->name, ret,
2342 __func__);
2343 dump_stack();
2346 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2347 mod->state = MODULE_STATE_LIVE;
2348 wake_up(&module_wq);
2350 mutex_lock(&module_mutex);
2351 /* Drop initial reference. */
2352 module_put(mod);
2353 unwind_remove_table(mod->unwind_info, 1);
2354 module_free(mod, mod->module_init);
2355 mod->module_init = NULL;
2356 mod->init_size = 0;
2357 mod->init_text_size = 0;
2358 mutex_unlock(&module_mutex);
2360 return 0;
2363 static inline int within(unsigned long addr, void *start, unsigned long size)
2365 return ((void *)addr >= start && (void *)addr < start + size);
2368 #ifdef CONFIG_KALLSYMS
2370 * This ignores the intensely annoying "mapping symbols" found
2371 * in ARM ELF files: $a, $t and $d.
2373 static inline int is_arm_mapping_symbol(const char *str)
2375 return str[0] == '$' && strchr("atd", str[1])
2376 && (str[2] == '\0' || str[2] == '.');
2379 static const char *get_ksymbol(struct module *mod,
2380 unsigned long addr,
2381 unsigned long *size,
2382 unsigned long *offset)
2384 unsigned int i, best = 0;
2385 unsigned long nextval;
2387 /* At worse, next value is at end of module */
2388 if (within(addr, mod->module_init, mod->init_size))
2389 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2390 else
2391 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2393 /* Scan for closest preceeding symbol, and next symbol. (ELF
2394 starts real symbols at 1). */
2395 for (i = 1; i < mod->num_symtab; i++) {
2396 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2397 continue;
2399 /* We ignore unnamed symbols: they're uninformative
2400 * and inserted at a whim. */
2401 if (mod->symtab[i].st_value <= addr
2402 && mod->symtab[i].st_value > mod->symtab[best].st_value
2403 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2404 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2405 best = i;
2406 if (mod->symtab[i].st_value > addr
2407 && mod->symtab[i].st_value < nextval
2408 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2409 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2410 nextval = mod->symtab[i].st_value;
2413 if (!best)
2414 return NULL;
2416 if (size)
2417 *size = nextval - mod->symtab[best].st_value;
2418 if (offset)
2419 *offset = addr - mod->symtab[best].st_value;
2420 return mod->strtab + mod->symtab[best].st_name;
2423 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2424 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2425 const char *module_address_lookup(unsigned long addr,
2426 unsigned long *size,
2427 unsigned long *offset,
2428 char **modname,
2429 char *namebuf)
2431 struct module *mod;
2432 const char *ret = NULL;
2434 preempt_disable();
2435 list_for_each_entry_rcu(mod, &modules, list) {
2436 if (within(addr, mod->module_init, mod->init_size)
2437 || within(addr, mod->module_core, mod->core_size)) {
2438 if (modname)
2439 *modname = mod->name;
2440 ret = get_ksymbol(mod, addr, size, offset);
2441 break;
2444 /* Make a copy in here where it's safe */
2445 if (ret) {
2446 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2447 ret = namebuf;
2449 preempt_enable();
2450 return ret;
2453 int lookup_module_symbol_name(unsigned long addr, char *symname)
2455 struct module *mod;
2457 preempt_disable();
2458 list_for_each_entry_rcu(mod, &modules, list) {
2459 if (within(addr, mod->module_init, mod->init_size) ||
2460 within(addr, mod->module_core, mod->core_size)) {
2461 const char *sym;
2463 sym = get_ksymbol(mod, addr, NULL, NULL);
2464 if (!sym)
2465 goto out;
2466 strlcpy(symname, sym, KSYM_NAME_LEN);
2467 preempt_enable();
2468 return 0;
2471 out:
2472 preempt_enable();
2473 return -ERANGE;
2476 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2477 unsigned long *offset, char *modname, char *name)
2479 struct module *mod;
2481 preempt_disable();
2482 list_for_each_entry_rcu(mod, &modules, list) {
2483 if (within(addr, mod->module_init, mod->init_size) ||
2484 within(addr, mod->module_core, mod->core_size)) {
2485 const char *sym;
2487 sym = get_ksymbol(mod, addr, size, offset);
2488 if (!sym)
2489 goto out;
2490 if (modname)
2491 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2492 if (name)
2493 strlcpy(name, sym, KSYM_NAME_LEN);
2494 preempt_enable();
2495 return 0;
2498 out:
2499 preempt_enable();
2500 return -ERANGE;
2503 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2504 char *name, char *module_name, int *exported)
2506 struct module *mod;
2508 preempt_disable();
2509 list_for_each_entry_rcu(mod, &modules, list) {
2510 if (symnum < mod->num_symtab) {
2511 *value = mod->symtab[symnum].st_value;
2512 *type = mod->symtab[symnum].st_info;
2513 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2514 KSYM_NAME_LEN);
2515 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2516 *exported = is_exported(name, mod);
2517 preempt_enable();
2518 return 0;
2520 symnum -= mod->num_symtab;
2522 preempt_enable();
2523 return -ERANGE;
2526 static unsigned long mod_find_symname(struct module *mod, const char *name)
2528 unsigned int i;
2530 for (i = 0; i < mod->num_symtab; i++)
2531 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2532 mod->symtab[i].st_info != 'U')
2533 return mod->symtab[i].st_value;
2534 return 0;
2537 /* Look for this name: can be of form module:name. */
2538 unsigned long module_kallsyms_lookup_name(const char *name)
2540 struct module *mod;
2541 char *colon;
2542 unsigned long ret = 0;
2544 /* Don't lock: we're in enough trouble already. */
2545 preempt_disable();
2546 if ((colon = strchr(name, ':')) != NULL) {
2547 *colon = '\0';
2548 if ((mod = find_module(name)) != NULL)
2549 ret = mod_find_symname(mod, colon+1);
2550 *colon = ':';
2551 } else {
2552 list_for_each_entry_rcu(mod, &modules, list)
2553 if ((ret = mod_find_symname(mod, name)) != 0)
2554 break;
2556 preempt_enable();
2557 return ret;
2559 #endif /* CONFIG_KALLSYMS */
2561 static char *module_flags(struct module *mod, char *buf)
2563 int bx = 0;
2565 if (mod->taints ||
2566 mod->state == MODULE_STATE_GOING ||
2567 mod->state == MODULE_STATE_COMING) {
2568 buf[bx++] = '(';
2569 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2570 buf[bx++] = 'P';
2571 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2572 buf[bx++] = 'F';
2573 if (mod->taints & (1 << TAINT_CRAP))
2574 buf[bx++] = 'C';
2576 * TAINT_FORCED_RMMOD: could be added.
2577 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2578 * apply to modules.
2581 /* Show a - for module-is-being-unloaded */
2582 if (mod->state == MODULE_STATE_GOING)
2583 buf[bx++] = '-';
2584 /* Show a + for module-is-being-loaded */
2585 if (mod->state == MODULE_STATE_COMING)
2586 buf[bx++] = '+';
2587 buf[bx++] = ')';
2589 buf[bx] = '\0';
2591 return buf;
2594 #ifdef CONFIG_PROC_FS
2595 /* Called by the /proc file system to return a list of modules. */
2596 static void *m_start(struct seq_file *m, loff_t *pos)
2598 mutex_lock(&module_mutex);
2599 return seq_list_start(&modules, *pos);
2602 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2604 return seq_list_next(p, &modules, pos);
2607 static void m_stop(struct seq_file *m, void *p)
2609 mutex_unlock(&module_mutex);
2612 static int m_show(struct seq_file *m, void *p)
2614 struct module *mod = list_entry(p, struct module, list);
2615 char buf[8];
2617 seq_printf(m, "%s %u",
2618 mod->name, mod->init_size + mod->core_size);
2619 print_unload_info(m, mod);
2621 /* Informative for users. */
2622 seq_printf(m, " %s",
2623 mod->state == MODULE_STATE_GOING ? "Unloading":
2624 mod->state == MODULE_STATE_COMING ? "Loading":
2625 "Live");
2626 /* Used by oprofile and other similar tools. */
2627 seq_printf(m, " 0x%p", mod->module_core);
2629 /* Taints info */
2630 if (mod->taints)
2631 seq_printf(m, " %s", module_flags(mod, buf));
2633 seq_printf(m, "\n");
2634 return 0;
2637 /* Format: modulename size refcount deps address
2639 Where refcount is a number or -, and deps is a comma-separated list
2640 of depends or -.
2642 static const struct seq_operations modules_op = {
2643 .start = m_start,
2644 .next = m_next,
2645 .stop = m_stop,
2646 .show = m_show
2649 static int modules_open(struct inode *inode, struct file *file)
2651 return seq_open(file, &modules_op);
2654 static const struct file_operations proc_modules_operations = {
2655 .open = modules_open,
2656 .read = seq_read,
2657 .llseek = seq_lseek,
2658 .release = seq_release,
2661 static int __init proc_modules_init(void)
2663 proc_create("modules", 0, NULL, &proc_modules_operations);
2664 return 0;
2666 module_init(proc_modules_init);
2667 #endif
2669 /* Given an address, look for it in the module exception tables. */
2670 const struct exception_table_entry *search_module_extables(unsigned long addr)
2672 const struct exception_table_entry *e = NULL;
2673 struct module *mod;
2675 preempt_disable();
2676 list_for_each_entry_rcu(mod, &modules, list) {
2677 if (mod->num_exentries == 0)
2678 continue;
2680 e = search_extable(mod->extable,
2681 mod->extable + mod->num_exentries - 1,
2682 addr);
2683 if (e)
2684 break;
2686 preempt_enable();
2688 /* Now, if we found one, we are running inside it now, hence
2689 we cannot unload the module, hence no refcnt needed. */
2690 return e;
2694 * Is this a valid module address?
2696 int is_module_address(unsigned long addr)
2698 struct module *mod;
2700 preempt_disable();
2702 list_for_each_entry_rcu(mod, &modules, list) {
2703 if (within(addr, mod->module_core, mod->core_size)) {
2704 preempt_enable();
2705 return 1;
2709 preempt_enable();
2711 return 0;
2715 /* Is this a valid kernel address? */
2716 struct module *__module_text_address(unsigned long addr)
2718 struct module *mod;
2720 if (addr < module_addr_min || addr > module_addr_max)
2721 return NULL;
2723 list_for_each_entry_rcu(mod, &modules, list)
2724 if (within(addr, mod->module_init, mod->init_text_size)
2725 || within(addr, mod->module_core, mod->core_text_size))
2726 return mod;
2727 return NULL;
2730 struct module *module_text_address(unsigned long addr)
2732 struct module *mod;
2734 preempt_disable();
2735 mod = __module_text_address(addr);
2736 preempt_enable();
2738 return mod;
2741 /* Don't grab lock, we're oopsing. */
2742 void print_modules(void)
2744 struct module *mod;
2745 char buf[8];
2747 printk("Modules linked in:");
2748 /* Most callers should already have preempt disabled, but make sure */
2749 preempt_disable();
2750 list_for_each_entry_rcu(mod, &modules, list)
2751 printk(" %s%s", mod->name, module_flags(mod, buf));
2752 preempt_enable();
2753 if (last_unloaded_module[0])
2754 printk(" [last unloaded: %s]", last_unloaded_module);
2755 printk("\n");
2758 #ifdef CONFIG_MODVERSIONS
2759 /* Generate the signature for struct module here, too, for modversions. */
2760 void struct_module(struct module *mod) { return; }
2761 EXPORT_SYMBOL(struct_module);
2762 #endif
2764 #ifdef CONFIG_MARKERS
2765 void module_update_markers(void)
2767 struct module *mod;
2769 mutex_lock(&module_mutex);
2770 list_for_each_entry(mod, &modules, list)
2771 if (!mod->taints)
2772 marker_update_probe_range(mod->markers,
2773 mod->markers + mod->num_markers);
2774 mutex_unlock(&module_mutex);
2776 #endif
2778 #ifdef CONFIG_TRACEPOINTS
2779 void module_update_tracepoints(void)
2781 struct module *mod;
2783 mutex_lock(&module_mutex);
2784 list_for_each_entry(mod, &modules, list)
2785 if (!mod->taints)
2786 tracepoint_update_probe_range(mod->tracepoints,
2787 mod->tracepoints + mod->num_tracepoints);
2788 mutex_unlock(&module_mutex);
2792 * Returns 0 if current not found.
2793 * Returns 1 if current found.
2795 int module_get_iter_tracepoints(struct tracepoint_iter *iter)
2797 struct module *iter_mod;
2798 int found = 0;
2800 mutex_lock(&module_mutex);
2801 list_for_each_entry(iter_mod, &modules, list) {
2802 if (!iter_mod->taints) {
2804 * Sorted module list
2806 if (iter_mod < iter->module)
2807 continue;
2808 else if (iter_mod > iter->module)
2809 iter->tracepoint = NULL;
2810 found = tracepoint_get_iter_range(&iter->tracepoint,
2811 iter_mod->tracepoints,
2812 iter_mod->tracepoints
2813 + iter_mod->num_tracepoints);
2814 if (found) {
2815 iter->module = iter_mod;
2816 break;
2820 mutex_unlock(&module_mutex);
2821 return found;
2823 #endif