USB: usb-storage: increase max_sectors for tape drives
[linux-2.6/mini2440.git] / kernel / module.c
blob1196f5d117002face7e8424f87024e94df9e8add
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/rculist.h>
47 #include <asm/uaccess.h>
48 #include <asm/cacheflush.h>
49 #include <linux/license.h>
50 #include <asm/sections.h>
51 #include <linux/tracepoint.h>
52 #include <linux/ftrace.h>
53 #include <linux/async.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 int cpu;
578 INIT_LIST_HEAD(&mod->modules_which_use_me);
579 for_each_possible_cpu(cpu)
580 local_set(__module_ref_addr(mod, cpu), 0);
581 /* Hold reference count during initialization. */
582 local_set(__module_ref_addr(mod, raw_smp_processor_id()), 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 total = 0;
721 int cpu;
723 for_each_possible_cpu(cpu)
724 total += local_read(__module_ref_addr(mod, cpu));
725 return total;
727 EXPORT_SYMBOL(module_refcount);
729 /* This exists whether we can unload or not */
730 static void free_module(struct module *mod);
732 static void wait_for_zero_refcount(struct module *mod)
734 /* Since we might sleep for some time, release the mutex first */
735 mutex_unlock(&module_mutex);
736 for (;;) {
737 DEBUGP("Looking at refcount...\n");
738 set_current_state(TASK_UNINTERRUPTIBLE);
739 if (module_refcount(mod) == 0)
740 break;
741 schedule();
743 current->state = TASK_RUNNING;
744 mutex_lock(&module_mutex);
747 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
748 unsigned int, flags)
750 struct module *mod;
751 char name[MODULE_NAME_LEN];
752 int ret, forced = 0;
754 if (!capable(CAP_SYS_MODULE))
755 return -EPERM;
757 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
758 return -EFAULT;
759 name[MODULE_NAME_LEN-1] = '\0';
761 /* Create stop_machine threads since free_module relies on
762 * a non-failing stop_machine call. */
763 ret = stop_machine_create();
764 if (ret)
765 return ret;
767 if (mutex_lock_interruptible(&module_mutex) != 0) {
768 ret = -EINTR;
769 goto out_stop;
772 mod = find_module(name);
773 if (!mod) {
774 ret = -ENOENT;
775 goto out;
778 if (!list_empty(&mod->modules_which_use_me)) {
779 /* Other modules depend on us: get rid of them first. */
780 ret = -EWOULDBLOCK;
781 goto out;
784 /* Doing init or already dying? */
785 if (mod->state != MODULE_STATE_LIVE) {
786 /* FIXME: if (force), slam module count and wake up
787 waiter --RR */
788 DEBUGP("%s already dying\n", mod->name);
789 ret = -EBUSY;
790 goto out;
793 /* If it has an init func, it must have an exit func to unload */
794 if (mod->init && !mod->exit) {
795 forced = try_force_unload(flags);
796 if (!forced) {
797 /* This module can't be removed */
798 ret = -EBUSY;
799 goto out;
803 /* Set this up before setting mod->state */
804 mod->waiter = current;
806 /* Stop the machine so refcounts can't move and disable module. */
807 ret = try_stop_module(mod, flags, &forced);
808 if (ret != 0)
809 goto out;
811 /* Never wait if forced. */
812 if (!forced && module_refcount(mod) != 0)
813 wait_for_zero_refcount(mod);
815 mutex_unlock(&module_mutex);
816 /* Final destruction now noone is using it. */
817 if (mod->exit != NULL)
818 mod->exit();
819 blocking_notifier_call_chain(&module_notify_list,
820 MODULE_STATE_GOING, mod);
821 async_synchronize_full();
822 mutex_lock(&module_mutex);
823 /* Store the name of the last unloaded module for diagnostic purposes */
824 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
825 unregister_dynamic_debug_module(mod->name);
826 free_module(mod);
828 out:
829 mutex_unlock(&module_mutex);
830 out_stop:
831 stop_machine_destroy();
832 return ret;
835 static inline void print_unload_info(struct seq_file *m, struct module *mod)
837 struct module_use *use;
838 int printed_something = 0;
840 seq_printf(m, " %u ", module_refcount(mod));
842 /* Always include a trailing , so userspace can differentiate
843 between this and the old multi-field proc format. */
844 list_for_each_entry(use, &mod->modules_which_use_me, list) {
845 printed_something = 1;
846 seq_printf(m, "%s,", use->module_which_uses->name);
849 if (mod->init != NULL && mod->exit == NULL) {
850 printed_something = 1;
851 seq_printf(m, "[permanent],");
854 if (!printed_something)
855 seq_printf(m, "-");
858 void __symbol_put(const char *symbol)
860 struct module *owner;
862 preempt_disable();
863 if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false)))
864 BUG();
865 module_put(owner);
866 preempt_enable();
868 EXPORT_SYMBOL(__symbol_put);
870 void symbol_put_addr(void *addr)
872 struct module *modaddr;
874 if (core_kernel_text((unsigned long)addr))
875 return;
877 if (!(modaddr = module_text_address((unsigned long)addr)))
878 BUG();
879 module_put(modaddr);
881 EXPORT_SYMBOL_GPL(symbol_put_addr);
883 static ssize_t show_refcnt(struct module_attribute *mattr,
884 struct module *mod, char *buffer)
886 return sprintf(buffer, "%u\n", module_refcount(mod));
889 static struct module_attribute refcnt = {
890 .attr = { .name = "refcnt", .mode = 0444 },
891 .show = show_refcnt,
894 void module_put(struct module *module)
896 if (module) {
897 unsigned int cpu = get_cpu();
898 local_dec(__module_ref_addr(module, cpu));
899 /* Maybe they're waiting for us to drop reference? */
900 if (unlikely(!module_is_live(module)))
901 wake_up_process(module->waiter);
902 put_cpu();
905 EXPORT_SYMBOL(module_put);
907 #else /* !CONFIG_MODULE_UNLOAD */
908 static inline void print_unload_info(struct seq_file *m, struct module *mod)
910 /* We don't know the usage count, or what modules are using. */
911 seq_printf(m, " - -");
914 static inline void module_unload_free(struct module *mod)
918 static inline int use_module(struct module *a, struct module *b)
920 return strong_try_module_get(b) == 0;
923 static inline void module_unload_init(struct module *mod)
926 #endif /* CONFIG_MODULE_UNLOAD */
928 static ssize_t show_initstate(struct module_attribute *mattr,
929 struct module *mod, char *buffer)
931 const char *state = "unknown";
933 switch (mod->state) {
934 case MODULE_STATE_LIVE:
935 state = "live";
936 break;
937 case MODULE_STATE_COMING:
938 state = "coming";
939 break;
940 case MODULE_STATE_GOING:
941 state = "going";
942 break;
944 return sprintf(buffer, "%s\n", state);
947 static struct module_attribute initstate = {
948 .attr = { .name = "initstate", .mode = 0444 },
949 .show = show_initstate,
952 static struct module_attribute *modinfo_attrs[] = {
953 &modinfo_version,
954 &modinfo_srcversion,
955 &initstate,
956 #ifdef CONFIG_MODULE_UNLOAD
957 &refcnt,
958 #endif
959 NULL,
962 static const char vermagic[] = VERMAGIC_STRING;
964 static int try_to_force_load(struct module *mod, const char *symname)
966 #ifdef CONFIG_MODULE_FORCE_LOAD
967 if (!test_taint(TAINT_FORCED_MODULE))
968 printk("%s: no version for \"%s\" found: kernel tainted.\n",
969 mod->name, symname);
970 add_taint_module(mod, TAINT_FORCED_MODULE);
971 return 0;
972 #else
973 return -ENOEXEC;
974 #endif
977 #ifdef CONFIG_MODVERSIONS
978 static int check_version(Elf_Shdr *sechdrs,
979 unsigned int versindex,
980 const char *symname,
981 struct module *mod,
982 const unsigned long *crc)
984 unsigned int i, num_versions;
985 struct modversion_info *versions;
987 /* Exporting module didn't supply crcs? OK, we're already tainted. */
988 if (!crc)
989 return 1;
991 /* No versions at all? modprobe --force does this. */
992 if (versindex == 0)
993 return try_to_force_load(mod, symname) == 0;
995 versions = (void *) sechdrs[versindex].sh_addr;
996 num_versions = sechdrs[versindex].sh_size
997 / sizeof(struct modversion_info);
999 for (i = 0; i < num_versions; i++) {
1000 if (strcmp(versions[i].name, symname) != 0)
1001 continue;
1003 if (versions[i].crc == *crc)
1004 return 1;
1005 DEBUGP("Found checksum %lX vs module %lX\n",
1006 *crc, versions[i].crc);
1007 goto bad_version;
1010 printk(KERN_WARNING "%s: no symbol version for %s\n",
1011 mod->name, symname);
1012 return 0;
1014 bad_version:
1015 printk("%s: disagrees about version of symbol %s\n",
1016 mod->name, symname);
1017 return 0;
1020 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1021 unsigned int versindex,
1022 struct module *mod)
1024 const unsigned long *crc;
1026 if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false)))
1027 BUG();
1028 return check_version(sechdrs, versindex, "struct_module", mod, crc);
1031 /* First part is kernel version, which we ignore if module has crcs. */
1032 static inline int same_magic(const char *amagic, const char *bmagic,
1033 bool has_crcs)
1035 if (has_crcs) {
1036 amagic += strcspn(amagic, " ");
1037 bmagic += strcspn(bmagic, " ");
1039 return strcmp(amagic, bmagic) == 0;
1041 #else
1042 static inline int check_version(Elf_Shdr *sechdrs,
1043 unsigned int versindex,
1044 const char *symname,
1045 struct module *mod,
1046 const unsigned long *crc)
1048 return 1;
1051 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1052 unsigned int versindex,
1053 struct module *mod)
1055 return 1;
1058 static inline int same_magic(const char *amagic, const char *bmagic,
1059 bool has_crcs)
1061 return strcmp(amagic, bmagic) == 0;
1063 #endif /* CONFIG_MODVERSIONS */
1065 /* Resolve a symbol for this module. I.e. if we find one, record usage.
1066 Must be holding module_mutex. */
1067 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
1068 unsigned int versindex,
1069 const char *name,
1070 struct module *mod)
1072 struct module *owner;
1073 unsigned long ret;
1074 const unsigned long *crc;
1076 ret = find_symbol(name, &owner, &crc,
1077 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1078 if (!IS_ERR_VALUE(ret)) {
1079 /* use_module can fail due to OOM,
1080 or module initialization or unloading */
1081 if (!check_version(sechdrs, versindex, name, mod, crc) ||
1082 !use_module(mod, owner))
1083 ret = -EINVAL;
1085 return ret;
1089 * /sys/module/foo/sections stuff
1090 * J. Corbet <corbet@lwn.net>
1092 #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1093 struct module_sect_attr
1095 struct module_attribute mattr;
1096 char *name;
1097 unsigned long address;
1100 struct module_sect_attrs
1102 struct attribute_group grp;
1103 unsigned int nsections;
1104 struct module_sect_attr attrs[0];
1107 static ssize_t module_sect_show(struct module_attribute *mattr,
1108 struct module *mod, char *buf)
1110 struct module_sect_attr *sattr =
1111 container_of(mattr, struct module_sect_attr, mattr);
1112 return sprintf(buf, "0x%lx\n", sattr->address);
1115 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1117 unsigned int section;
1119 for (section = 0; section < sect_attrs->nsections; section++)
1120 kfree(sect_attrs->attrs[section].name);
1121 kfree(sect_attrs);
1124 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1125 char *secstrings, Elf_Shdr *sechdrs)
1127 unsigned int nloaded = 0, i, size[2];
1128 struct module_sect_attrs *sect_attrs;
1129 struct module_sect_attr *sattr;
1130 struct attribute **gattr;
1132 /* Count loaded sections and allocate structures */
1133 for (i = 0; i < nsect; i++)
1134 if (sechdrs[i].sh_flags & SHF_ALLOC)
1135 nloaded++;
1136 size[0] = ALIGN(sizeof(*sect_attrs)
1137 + nloaded * sizeof(sect_attrs->attrs[0]),
1138 sizeof(sect_attrs->grp.attrs[0]));
1139 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1140 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1141 if (sect_attrs == NULL)
1142 return;
1144 /* Setup section attributes. */
1145 sect_attrs->grp.name = "sections";
1146 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1148 sect_attrs->nsections = 0;
1149 sattr = &sect_attrs->attrs[0];
1150 gattr = &sect_attrs->grp.attrs[0];
1151 for (i = 0; i < nsect; i++) {
1152 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1153 continue;
1154 sattr->address = sechdrs[i].sh_addr;
1155 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1156 GFP_KERNEL);
1157 if (sattr->name == NULL)
1158 goto out;
1159 sect_attrs->nsections++;
1160 sattr->mattr.show = module_sect_show;
1161 sattr->mattr.store = NULL;
1162 sattr->mattr.attr.name = sattr->name;
1163 sattr->mattr.attr.mode = S_IRUGO;
1164 *(gattr++) = &(sattr++)->mattr.attr;
1166 *gattr = NULL;
1168 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1169 goto out;
1171 mod->sect_attrs = sect_attrs;
1172 return;
1173 out:
1174 free_sect_attrs(sect_attrs);
1177 static void remove_sect_attrs(struct module *mod)
1179 if (mod->sect_attrs) {
1180 sysfs_remove_group(&mod->mkobj.kobj,
1181 &mod->sect_attrs->grp);
1182 /* We are positive that no one is using any sect attrs
1183 * at this point. Deallocate immediately. */
1184 free_sect_attrs(mod->sect_attrs);
1185 mod->sect_attrs = NULL;
1190 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1193 struct module_notes_attrs {
1194 struct kobject *dir;
1195 unsigned int notes;
1196 struct bin_attribute attrs[0];
1199 static ssize_t module_notes_read(struct kobject *kobj,
1200 struct bin_attribute *bin_attr,
1201 char *buf, loff_t pos, size_t count)
1204 * The caller checked the pos and count against our size.
1206 memcpy(buf, bin_attr->private + pos, count);
1207 return count;
1210 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1211 unsigned int i)
1213 if (notes_attrs->dir) {
1214 while (i-- > 0)
1215 sysfs_remove_bin_file(notes_attrs->dir,
1216 &notes_attrs->attrs[i]);
1217 kobject_put(notes_attrs->dir);
1219 kfree(notes_attrs);
1222 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1223 char *secstrings, Elf_Shdr *sechdrs)
1225 unsigned int notes, loaded, i;
1226 struct module_notes_attrs *notes_attrs;
1227 struct bin_attribute *nattr;
1229 /* Count notes sections and allocate structures. */
1230 notes = 0;
1231 for (i = 0; i < nsect; i++)
1232 if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
1233 (sechdrs[i].sh_type == SHT_NOTE))
1234 ++notes;
1236 if (notes == 0)
1237 return;
1239 notes_attrs = kzalloc(sizeof(*notes_attrs)
1240 + notes * sizeof(notes_attrs->attrs[0]),
1241 GFP_KERNEL);
1242 if (notes_attrs == NULL)
1243 return;
1245 notes_attrs->notes = notes;
1246 nattr = &notes_attrs->attrs[0];
1247 for (loaded = i = 0; i < nsect; ++i) {
1248 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1249 continue;
1250 if (sechdrs[i].sh_type == SHT_NOTE) {
1251 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1252 nattr->attr.mode = S_IRUGO;
1253 nattr->size = sechdrs[i].sh_size;
1254 nattr->private = (void *) sechdrs[i].sh_addr;
1255 nattr->read = module_notes_read;
1256 ++nattr;
1258 ++loaded;
1261 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1262 if (!notes_attrs->dir)
1263 goto out;
1265 for (i = 0; i < notes; ++i)
1266 if (sysfs_create_bin_file(notes_attrs->dir,
1267 &notes_attrs->attrs[i]))
1268 goto out;
1270 mod->notes_attrs = notes_attrs;
1271 return;
1273 out:
1274 free_notes_attrs(notes_attrs, i);
1277 static void remove_notes_attrs(struct module *mod)
1279 if (mod->notes_attrs)
1280 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1283 #else
1285 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1286 char *sectstrings, Elf_Shdr *sechdrs)
1290 static inline void remove_sect_attrs(struct module *mod)
1294 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1295 char *sectstrings, Elf_Shdr *sechdrs)
1299 static inline void remove_notes_attrs(struct module *mod)
1302 #endif
1304 #ifdef CONFIG_SYSFS
1305 int module_add_modinfo_attrs(struct module *mod)
1307 struct module_attribute *attr;
1308 struct module_attribute *temp_attr;
1309 int error = 0;
1310 int i;
1312 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1313 (ARRAY_SIZE(modinfo_attrs) + 1)),
1314 GFP_KERNEL);
1315 if (!mod->modinfo_attrs)
1316 return -ENOMEM;
1318 temp_attr = mod->modinfo_attrs;
1319 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1320 if (!attr->test ||
1321 (attr->test && attr->test(mod))) {
1322 memcpy(temp_attr, attr, sizeof(*temp_attr));
1323 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1324 ++temp_attr;
1327 return error;
1330 void module_remove_modinfo_attrs(struct module *mod)
1332 struct module_attribute *attr;
1333 int i;
1335 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1336 /* pick a field to test for end of list */
1337 if (!attr->attr.name)
1338 break;
1339 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1340 if (attr->free)
1341 attr->free(mod);
1343 kfree(mod->modinfo_attrs);
1346 int mod_sysfs_init(struct module *mod)
1348 int err;
1349 struct kobject *kobj;
1351 if (!module_sysfs_initialized) {
1352 printk(KERN_ERR "%s: module sysfs not initialized\n",
1353 mod->name);
1354 err = -EINVAL;
1355 goto out;
1358 kobj = kset_find_obj(module_kset, mod->name);
1359 if (kobj) {
1360 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1361 kobject_put(kobj);
1362 err = -EINVAL;
1363 goto out;
1366 mod->mkobj.mod = mod;
1368 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1369 mod->mkobj.kobj.kset = module_kset;
1370 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1371 "%s", mod->name);
1372 if (err)
1373 kobject_put(&mod->mkobj.kobj);
1375 /* delay uevent until full sysfs population */
1376 out:
1377 return err;
1380 int mod_sysfs_setup(struct module *mod,
1381 struct kernel_param *kparam,
1382 unsigned int num_params)
1384 int err;
1386 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1387 if (!mod->holders_dir) {
1388 err = -ENOMEM;
1389 goto out_unreg;
1392 err = module_param_sysfs_setup(mod, kparam, num_params);
1393 if (err)
1394 goto out_unreg_holders;
1396 err = module_add_modinfo_attrs(mod);
1397 if (err)
1398 goto out_unreg_param;
1400 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1401 return 0;
1403 out_unreg_param:
1404 module_param_sysfs_remove(mod);
1405 out_unreg_holders:
1406 kobject_put(mod->holders_dir);
1407 out_unreg:
1408 kobject_put(&mod->mkobj.kobj);
1409 return err;
1412 static void mod_sysfs_fini(struct module *mod)
1414 kobject_put(&mod->mkobj.kobj);
1417 #else /* CONFIG_SYSFS */
1419 static void mod_sysfs_fini(struct module *mod)
1423 #endif /* CONFIG_SYSFS */
1425 static void mod_kobject_remove(struct module *mod)
1427 module_remove_modinfo_attrs(mod);
1428 module_param_sysfs_remove(mod);
1429 kobject_put(mod->mkobj.drivers_dir);
1430 kobject_put(mod->holders_dir);
1431 mod_sysfs_fini(mod);
1435 * unlink the module with the whole machine is stopped with interrupts off
1436 * - this defends against kallsyms not taking locks
1438 static int __unlink_module(void *_mod)
1440 struct module *mod = _mod;
1441 list_del(&mod->list);
1442 return 0;
1445 /* Free a module, remove from lists, etc (must hold module_mutex). */
1446 static void free_module(struct module *mod)
1448 /* Delete from various lists */
1449 stop_machine(__unlink_module, mod, NULL);
1450 remove_notes_attrs(mod);
1451 remove_sect_attrs(mod);
1452 mod_kobject_remove(mod);
1454 /* Arch-specific cleanup. */
1455 module_arch_cleanup(mod);
1457 /* Module unload stuff */
1458 module_unload_free(mod);
1460 /* release any pointers to mcount in this module */
1461 ftrace_release(mod->module_core, mod->core_size);
1463 /* This may be NULL, but that's OK */
1464 module_free(mod, mod->module_init);
1465 kfree(mod->args);
1466 if (mod->percpu)
1467 percpu_modfree(mod->percpu);
1468 #if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
1469 if (mod->refptr)
1470 percpu_modfree(mod->refptr);
1471 #endif
1472 /* Free lock-classes: */
1473 lockdep_free_key_range(mod->module_core, mod->core_size);
1475 /* Finally, free the core (containing the module structure) */
1476 module_free(mod, mod->module_core);
1479 void *__symbol_get(const char *symbol)
1481 struct module *owner;
1482 unsigned long value;
1484 preempt_disable();
1485 value = find_symbol(symbol, &owner, NULL, true, true);
1486 if (IS_ERR_VALUE(value))
1487 value = 0;
1488 else if (strong_try_module_get(owner))
1489 value = 0;
1490 preempt_enable();
1492 return (void *)value;
1494 EXPORT_SYMBOL_GPL(__symbol_get);
1497 * Ensure that an exported symbol [global namespace] does not already exist
1498 * in the kernel or in some other module's exported symbol table.
1500 static int verify_export_symbols(struct module *mod)
1502 unsigned int i;
1503 struct module *owner;
1504 const struct kernel_symbol *s;
1505 struct {
1506 const struct kernel_symbol *sym;
1507 unsigned int num;
1508 } arr[] = {
1509 { mod->syms, mod->num_syms },
1510 { mod->gpl_syms, mod->num_gpl_syms },
1511 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1512 #ifdef CONFIG_UNUSED_SYMBOLS
1513 { mod->unused_syms, mod->num_unused_syms },
1514 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1515 #endif
1518 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1519 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1520 if (!IS_ERR_VALUE(find_symbol(s->name, &owner,
1521 NULL, true, false))) {
1522 printk(KERN_ERR
1523 "%s: exports duplicate symbol %s"
1524 " (owned by %s)\n",
1525 mod->name, s->name, module_name(owner));
1526 return -ENOEXEC;
1530 return 0;
1533 /* Change all symbols so that st_value encodes the pointer directly. */
1534 static int simplify_symbols(Elf_Shdr *sechdrs,
1535 unsigned int symindex,
1536 const char *strtab,
1537 unsigned int versindex,
1538 unsigned int pcpuindex,
1539 struct module *mod)
1541 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1542 unsigned long secbase;
1543 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1544 int ret = 0;
1546 for (i = 1; i < n; i++) {
1547 switch (sym[i].st_shndx) {
1548 case SHN_COMMON:
1549 /* We compiled with -fno-common. These are not
1550 supposed to happen. */
1551 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1552 printk("%s: please compile with -fno-common\n",
1553 mod->name);
1554 ret = -ENOEXEC;
1555 break;
1557 case SHN_ABS:
1558 /* Don't need to do anything */
1559 DEBUGP("Absolute symbol: 0x%08lx\n",
1560 (long)sym[i].st_value);
1561 break;
1563 case SHN_UNDEF:
1564 sym[i].st_value
1565 = resolve_symbol(sechdrs, versindex,
1566 strtab + sym[i].st_name, mod);
1568 /* Ok if resolved. */
1569 if (!IS_ERR_VALUE(sym[i].st_value))
1570 break;
1571 /* Ok if weak. */
1572 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1573 break;
1575 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1576 mod->name, strtab + sym[i].st_name);
1577 ret = -ENOENT;
1578 break;
1580 default:
1581 /* Divert to percpu allocation if a percpu var. */
1582 if (sym[i].st_shndx == pcpuindex)
1583 secbase = (unsigned long)mod->percpu;
1584 else
1585 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1586 sym[i].st_value += secbase;
1587 break;
1591 return ret;
1594 /* Additional bytes needed by arch in front of individual sections */
1595 unsigned int __weak arch_mod_section_prepend(struct module *mod,
1596 unsigned int section)
1598 /* default implementation just returns zero */
1599 return 0;
1602 /* Update size with this section: return offset. */
1603 static long get_offset(struct module *mod, unsigned int *size,
1604 Elf_Shdr *sechdr, unsigned int section)
1606 long ret;
1608 *size += arch_mod_section_prepend(mod, section);
1609 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1610 *size = ret + sechdr->sh_size;
1611 return ret;
1614 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1615 might -- code, read-only data, read-write data, small data. Tally
1616 sizes, and place the offsets into sh_entsize fields: high bit means it
1617 belongs in init. */
1618 static void layout_sections(struct module *mod,
1619 const Elf_Ehdr *hdr,
1620 Elf_Shdr *sechdrs,
1621 const char *secstrings)
1623 static unsigned long const masks[][2] = {
1624 /* NOTE: all executable code must be the first section
1625 * in this array; otherwise modify the text_size
1626 * finder in the two loops below */
1627 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1628 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1629 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1630 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1632 unsigned int m, i;
1634 for (i = 0; i < hdr->e_shnum; i++)
1635 sechdrs[i].sh_entsize = ~0UL;
1637 DEBUGP("Core section allocation order:\n");
1638 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1639 for (i = 0; i < hdr->e_shnum; ++i) {
1640 Elf_Shdr *s = &sechdrs[i];
1642 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1643 || (s->sh_flags & masks[m][1])
1644 || s->sh_entsize != ~0UL
1645 || strncmp(secstrings + s->sh_name,
1646 ".init", 5) == 0)
1647 continue;
1648 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1649 DEBUGP("\t%s\n", secstrings + s->sh_name);
1651 if (m == 0)
1652 mod->core_text_size = mod->core_size;
1655 DEBUGP("Init section allocation order:\n");
1656 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1657 for (i = 0; i < hdr->e_shnum; ++i) {
1658 Elf_Shdr *s = &sechdrs[i];
1660 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1661 || (s->sh_flags & masks[m][1])
1662 || s->sh_entsize != ~0UL
1663 || strncmp(secstrings + s->sh_name,
1664 ".init", 5) != 0)
1665 continue;
1666 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1667 | INIT_OFFSET_MASK);
1668 DEBUGP("\t%s\n", secstrings + s->sh_name);
1670 if (m == 0)
1671 mod->init_text_size = mod->init_size;
1675 static void set_license(struct module *mod, const char *license)
1677 if (!license)
1678 license = "unspecified";
1680 if (!license_is_gpl_compatible(license)) {
1681 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1682 printk(KERN_WARNING "%s: module license '%s' taints "
1683 "kernel.\n", mod->name, license);
1684 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1688 /* Parse tag=value strings from .modinfo section */
1689 static char *next_string(char *string, unsigned long *secsize)
1691 /* Skip non-zero chars */
1692 while (string[0]) {
1693 string++;
1694 if ((*secsize)-- <= 1)
1695 return NULL;
1698 /* Skip any zero padding. */
1699 while (!string[0]) {
1700 string++;
1701 if ((*secsize)-- <= 1)
1702 return NULL;
1704 return string;
1707 static char *get_modinfo(Elf_Shdr *sechdrs,
1708 unsigned int info,
1709 const char *tag)
1711 char *p;
1712 unsigned int taglen = strlen(tag);
1713 unsigned long size = sechdrs[info].sh_size;
1715 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1716 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1717 return p + taglen + 1;
1719 return NULL;
1722 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1723 unsigned int infoindex)
1725 struct module_attribute *attr;
1726 int i;
1728 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1729 if (attr->setup)
1730 attr->setup(mod,
1731 get_modinfo(sechdrs,
1732 infoindex,
1733 attr->attr.name));
1737 #ifdef CONFIG_KALLSYMS
1739 /* lookup symbol in given range of kernel_symbols */
1740 static const struct kernel_symbol *lookup_symbol(const char *name,
1741 const struct kernel_symbol *start,
1742 const struct kernel_symbol *stop)
1744 const struct kernel_symbol *ks = start;
1745 for (; ks < stop; ks++)
1746 if (strcmp(ks->name, name) == 0)
1747 return ks;
1748 return NULL;
1751 static int is_exported(const char *name, unsigned long value,
1752 const struct module *mod)
1754 const struct kernel_symbol *ks;
1755 if (!mod)
1756 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1757 else
1758 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1759 return ks != NULL && ks->value == value;
1762 /* As per nm */
1763 static char elf_type(const Elf_Sym *sym,
1764 Elf_Shdr *sechdrs,
1765 const char *secstrings,
1766 struct module *mod)
1768 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1769 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1770 return 'v';
1771 else
1772 return 'w';
1774 if (sym->st_shndx == SHN_UNDEF)
1775 return 'U';
1776 if (sym->st_shndx == SHN_ABS)
1777 return 'a';
1778 if (sym->st_shndx >= SHN_LORESERVE)
1779 return '?';
1780 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1781 return 't';
1782 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1783 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1784 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1785 return 'r';
1786 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1787 return 'g';
1788 else
1789 return 'd';
1791 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1792 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1793 return 's';
1794 else
1795 return 'b';
1797 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1798 ".debug", strlen(".debug")) == 0)
1799 return 'n';
1800 return '?';
1803 static void add_kallsyms(struct module *mod,
1804 Elf_Shdr *sechdrs,
1805 unsigned int symindex,
1806 unsigned int strindex,
1807 const char *secstrings)
1809 unsigned int i;
1811 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1812 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1813 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1815 /* Set types up while we still have access to sections. */
1816 for (i = 0; i < mod->num_symtab; i++)
1817 mod->symtab[i].st_info
1818 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1820 #else
1821 static inline void add_kallsyms(struct module *mod,
1822 Elf_Shdr *sechdrs,
1823 unsigned int symindex,
1824 unsigned int strindex,
1825 const char *secstrings)
1828 #endif /* CONFIG_KALLSYMS */
1830 static void dynamic_printk_setup(struct mod_debug *debug, unsigned int num)
1832 #ifdef CONFIG_DYNAMIC_PRINTK_DEBUG
1833 unsigned int i;
1835 for (i = 0; i < num; i++) {
1836 register_dynamic_debug_module(debug[i].modname,
1837 debug[i].type,
1838 debug[i].logical_modname,
1839 debug[i].flag_names,
1840 debug[i].hash, debug[i].hash2);
1842 #endif /* CONFIG_DYNAMIC_PRINTK_DEBUG */
1845 static void *module_alloc_update_bounds(unsigned long size)
1847 void *ret = module_alloc(size);
1849 if (ret) {
1850 /* Update module bounds. */
1851 if ((unsigned long)ret < module_addr_min)
1852 module_addr_min = (unsigned long)ret;
1853 if ((unsigned long)ret + size > module_addr_max)
1854 module_addr_max = (unsigned long)ret + size;
1856 return ret;
1859 /* Allocate and load the module: note that size of section 0 is always
1860 zero, and we rely on this for optional sections. */
1861 static noinline struct module *load_module(void __user *umod,
1862 unsigned long len,
1863 const char __user *uargs)
1865 Elf_Ehdr *hdr;
1866 Elf_Shdr *sechdrs;
1867 char *secstrings, *args, *modmagic, *strtab = NULL;
1868 char *staging;
1869 unsigned int i;
1870 unsigned int symindex = 0;
1871 unsigned int strindex = 0;
1872 unsigned int modindex, versindex, infoindex, pcpuindex;
1873 unsigned int num_kp, num_mcount;
1874 struct kernel_param *kp;
1875 struct module *mod;
1876 long err = 0;
1877 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1878 unsigned long *mseg;
1879 mm_segment_t old_fs;
1881 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1882 umod, len, uargs);
1883 if (len < sizeof(*hdr))
1884 return ERR_PTR(-ENOEXEC);
1886 /* Suck in entire file: we'll want most of it. */
1887 /* vmalloc barfs on "unusual" numbers. Check here */
1888 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1889 return ERR_PTR(-ENOMEM);
1891 /* Create stop_machine threads since the error path relies on
1892 * a non-failing stop_machine call. */
1893 err = stop_machine_create();
1894 if (err)
1895 goto free_hdr;
1897 if (copy_from_user(hdr, umod, len) != 0) {
1898 err = -EFAULT;
1899 goto free_hdr;
1902 /* Sanity checks against insmoding binaries or wrong arch,
1903 weird elf version */
1904 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
1905 || hdr->e_type != ET_REL
1906 || !elf_check_arch(hdr)
1907 || hdr->e_shentsize != sizeof(*sechdrs)) {
1908 err = -ENOEXEC;
1909 goto free_hdr;
1912 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1913 goto truncated;
1915 /* Convenience variables */
1916 sechdrs = (void *)hdr + hdr->e_shoff;
1917 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1918 sechdrs[0].sh_addr = 0;
1920 for (i = 1; i < hdr->e_shnum; i++) {
1921 if (sechdrs[i].sh_type != SHT_NOBITS
1922 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1923 goto truncated;
1925 /* Mark all sections sh_addr with their address in the
1926 temporary image. */
1927 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1929 /* Internal symbols and strings. */
1930 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1931 symindex = i;
1932 strindex = sechdrs[i].sh_link;
1933 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1935 #ifndef CONFIG_MODULE_UNLOAD
1936 /* Don't load .exit sections */
1937 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1938 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1939 #endif
1942 modindex = find_sec(hdr, sechdrs, secstrings,
1943 ".gnu.linkonce.this_module");
1944 if (!modindex) {
1945 printk(KERN_WARNING "No module found in object\n");
1946 err = -ENOEXEC;
1947 goto free_hdr;
1949 /* This is temporary: point mod into copy of data. */
1950 mod = (void *)sechdrs[modindex].sh_addr;
1952 if (symindex == 0) {
1953 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1954 mod->name);
1955 err = -ENOEXEC;
1956 goto free_hdr;
1959 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1960 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1961 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1963 /* Don't keep modinfo and version sections. */
1964 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1965 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1966 #ifdef CONFIG_KALLSYMS
1967 /* Keep symbol and string tables for decoding later. */
1968 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1969 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1970 #endif
1972 /* Check module struct version now, before we try to use module. */
1973 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1974 err = -ENOEXEC;
1975 goto free_hdr;
1978 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1979 /* This is allowed: modprobe --force will invalidate it. */
1980 if (!modmagic) {
1981 err = try_to_force_load(mod, "magic");
1982 if (err)
1983 goto free_hdr;
1984 } else if (!same_magic(modmagic, vermagic, versindex)) {
1985 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1986 mod->name, modmagic, vermagic);
1987 err = -ENOEXEC;
1988 goto free_hdr;
1991 staging = get_modinfo(sechdrs, infoindex, "staging");
1992 if (staging) {
1993 add_taint_module(mod, TAINT_CRAP);
1994 printk(KERN_WARNING "%s: module is from the staging directory,"
1995 " the quality is unknown, you have been warned.\n",
1996 mod->name);
1999 /* Now copy in args */
2000 args = strndup_user(uargs, ~0UL >> 1);
2001 if (IS_ERR(args)) {
2002 err = PTR_ERR(args);
2003 goto free_hdr;
2006 if (find_module(mod->name)) {
2007 err = -EEXIST;
2008 goto free_mod;
2011 mod->state = MODULE_STATE_COMING;
2013 /* Allow arches to frob section contents and sizes. */
2014 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
2015 if (err < 0)
2016 goto free_mod;
2018 if (pcpuindex) {
2019 /* We have a special allocation for this section. */
2020 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
2021 sechdrs[pcpuindex].sh_addralign,
2022 mod->name);
2023 if (!percpu) {
2024 err = -ENOMEM;
2025 goto free_mod;
2027 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2028 mod->percpu = percpu;
2031 /* Determine total sizes, and put offsets in sh_entsize. For now
2032 this is done generically; there doesn't appear to be any
2033 special cases for the architectures. */
2034 layout_sections(mod, hdr, sechdrs, secstrings);
2036 /* Do the allocs. */
2037 ptr = module_alloc_update_bounds(mod->core_size);
2038 if (!ptr) {
2039 err = -ENOMEM;
2040 goto free_percpu;
2042 memset(ptr, 0, mod->core_size);
2043 mod->module_core = ptr;
2045 ptr = module_alloc_update_bounds(mod->init_size);
2046 if (!ptr && mod->init_size) {
2047 err = -ENOMEM;
2048 goto free_core;
2050 memset(ptr, 0, mod->init_size);
2051 mod->module_init = ptr;
2053 /* Transfer each section which specifies SHF_ALLOC */
2054 DEBUGP("final section addresses:\n");
2055 for (i = 0; i < hdr->e_shnum; i++) {
2056 void *dest;
2058 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2059 continue;
2061 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2062 dest = mod->module_init
2063 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2064 else
2065 dest = mod->module_core + sechdrs[i].sh_entsize;
2067 if (sechdrs[i].sh_type != SHT_NOBITS)
2068 memcpy(dest, (void *)sechdrs[i].sh_addr,
2069 sechdrs[i].sh_size);
2070 /* Update sh_addr to point to copy in image. */
2071 sechdrs[i].sh_addr = (unsigned long)dest;
2072 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2074 /* Module has been moved. */
2075 mod = (void *)sechdrs[modindex].sh_addr;
2077 #if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
2078 mod->refptr = percpu_modalloc(sizeof(local_t), __alignof__(local_t),
2079 mod->name);
2080 if (!mod->refptr) {
2081 err = -ENOMEM;
2082 goto free_init;
2084 #endif
2085 /* Now we've moved module, initialize linked lists, etc. */
2086 module_unload_init(mod);
2088 /* add kobject, so we can reference it. */
2089 err = mod_sysfs_init(mod);
2090 if (err)
2091 goto free_unload;
2093 /* Set up license info based on the info section */
2094 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2097 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2098 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2099 * using GPL-only symbols it needs.
2101 if (strcmp(mod->name, "ndiswrapper") == 0)
2102 add_taint(TAINT_PROPRIETARY_MODULE);
2104 /* driverloader was caught wrongly pretending to be under GPL */
2105 if (strcmp(mod->name, "driverloader") == 0)
2106 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2108 /* Set up MODINFO_ATTR fields */
2109 setup_modinfo(mod, sechdrs, infoindex);
2111 /* Fix up syms, so that st_value is a pointer to location. */
2112 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2113 mod);
2114 if (err < 0)
2115 goto cleanup;
2117 /* Now we've got everything in the final locations, we can
2118 * find optional sections. */
2119 kp = section_objs(hdr, sechdrs, secstrings, "__param", sizeof(*kp),
2120 &num_kp);
2121 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2122 sizeof(*mod->syms), &mod->num_syms);
2123 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2124 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2125 sizeof(*mod->gpl_syms),
2126 &mod->num_gpl_syms);
2127 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2128 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2129 "__ksymtab_gpl_future",
2130 sizeof(*mod->gpl_future_syms),
2131 &mod->num_gpl_future_syms);
2132 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2133 "__kcrctab_gpl_future");
2135 #ifdef CONFIG_UNUSED_SYMBOLS
2136 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2137 "__ksymtab_unused",
2138 sizeof(*mod->unused_syms),
2139 &mod->num_unused_syms);
2140 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2141 "__kcrctab_unused");
2142 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2143 "__ksymtab_unused_gpl",
2144 sizeof(*mod->unused_gpl_syms),
2145 &mod->num_unused_gpl_syms);
2146 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2147 "__kcrctab_unused_gpl");
2148 #endif
2150 #ifdef CONFIG_MARKERS
2151 mod->markers = section_objs(hdr, sechdrs, secstrings, "__markers",
2152 sizeof(*mod->markers), &mod->num_markers);
2153 #endif
2154 #ifdef CONFIG_TRACEPOINTS
2155 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2156 "__tracepoints",
2157 sizeof(*mod->tracepoints),
2158 &mod->num_tracepoints);
2159 #endif
2161 #ifdef CONFIG_MODVERSIONS
2162 if ((mod->num_syms && !mod->crcs)
2163 || (mod->num_gpl_syms && !mod->gpl_crcs)
2164 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2165 #ifdef CONFIG_UNUSED_SYMBOLS
2166 || (mod->num_unused_syms && !mod->unused_crcs)
2167 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2168 #endif
2170 printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name);
2171 err = try_to_force_load(mod, "nocrc");
2172 if (err)
2173 goto cleanup;
2175 #endif
2177 /* Now do relocations. */
2178 for (i = 1; i < hdr->e_shnum; i++) {
2179 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2180 unsigned int info = sechdrs[i].sh_info;
2182 /* Not a valid relocation section? */
2183 if (info >= hdr->e_shnum)
2184 continue;
2186 /* Don't bother with non-allocated sections */
2187 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2188 continue;
2190 if (sechdrs[i].sh_type == SHT_REL)
2191 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2192 else if (sechdrs[i].sh_type == SHT_RELA)
2193 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2194 mod);
2195 if (err < 0)
2196 goto cleanup;
2199 /* Find duplicate symbols */
2200 err = verify_export_symbols(mod);
2201 if (err < 0)
2202 goto cleanup;
2204 /* Set up and sort exception table */
2205 mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
2206 sizeof(*mod->extable), &mod->num_exentries);
2207 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2209 /* Finally, copy percpu area over. */
2210 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
2211 sechdrs[pcpuindex].sh_size);
2213 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
2215 if (!mod->taints) {
2216 struct mod_debug *debug;
2217 unsigned int num_debug;
2219 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2220 sizeof(*debug), &num_debug);
2221 dynamic_printk_setup(debug, num_debug);
2224 /* sechdrs[0].sh_size is always zero */
2225 mseg = section_objs(hdr, sechdrs, secstrings, "__mcount_loc",
2226 sizeof(*mseg), &num_mcount);
2227 ftrace_init_module(mod, mseg, mseg + num_mcount);
2229 err = module_finalize(hdr, sechdrs, mod);
2230 if (err < 0)
2231 goto cleanup;
2233 /* flush the icache in correct context */
2234 old_fs = get_fs();
2235 set_fs(KERNEL_DS);
2238 * Flush the instruction cache, since we've played with text.
2239 * Do it before processing of module parameters, so the module
2240 * can provide parameter accessor functions of its own.
2242 if (mod->module_init)
2243 flush_icache_range((unsigned long)mod->module_init,
2244 (unsigned long)mod->module_init
2245 + mod->init_size);
2246 flush_icache_range((unsigned long)mod->module_core,
2247 (unsigned long)mod->module_core + mod->core_size);
2249 set_fs(old_fs);
2251 mod->args = args;
2252 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2253 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2254 mod->name);
2256 /* Now sew it into the lists so we can get lockdep and oops
2257 * info during argument parsing. Noone should access us, since
2258 * strong_try_module_get() will fail.
2259 * lockdep/oops can run asynchronous, so use the RCU list insertion
2260 * function to insert in a way safe to concurrent readers.
2261 * The mutex protects against concurrent writers.
2263 list_add_rcu(&mod->list, &modules);
2265 err = parse_args(mod->name, mod->args, kp, num_kp, NULL);
2266 if (err < 0)
2267 goto unlink;
2269 err = mod_sysfs_setup(mod, kp, num_kp);
2270 if (err < 0)
2271 goto unlink;
2272 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2273 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2275 /* Get rid of temporary copy */
2276 vfree(hdr);
2278 stop_machine_destroy();
2279 /* Done! */
2280 return mod;
2282 unlink:
2283 stop_machine(__unlink_module, mod, NULL);
2284 module_arch_cleanup(mod);
2285 cleanup:
2286 kobject_del(&mod->mkobj.kobj);
2287 kobject_put(&mod->mkobj.kobj);
2288 ftrace_release(mod->module_core, mod->core_size);
2289 free_unload:
2290 module_unload_free(mod);
2291 free_init:
2292 #if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
2293 percpu_modfree(mod->refptr);
2294 #endif
2295 module_free(mod, mod->module_init);
2296 free_core:
2297 module_free(mod, mod->module_core);
2298 /* mod will be freed with core. Don't access it beyond this line! */
2299 free_percpu:
2300 if (percpu)
2301 percpu_modfree(percpu);
2302 free_mod:
2303 kfree(args);
2304 free_hdr:
2305 vfree(hdr);
2306 stop_machine_destroy();
2307 return ERR_PTR(err);
2309 truncated:
2310 printk(KERN_ERR "Module len %lu truncated\n", len);
2311 err = -ENOEXEC;
2312 goto free_hdr;
2315 /* This is where the real work happens */
2316 SYSCALL_DEFINE3(init_module, void __user *, umod,
2317 unsigned long, len, const char __user *, uargs)
2319 struct module *mod;
2320 int ret = 0;
2322 /* Must have permission */
2323 if (!capable(CAP_SYS_MODULE))
2324 return -EPERM;
2326 /* Only one module load at a time, please */
2327 if (mutex_lock_interruptible(&module_mutex) != 0)
2328 return -EINTR;
2330 /* Do all the hard work */
2331 mod = load_module(umod, len, uargs);
2332 if (IS_ERR(mod)) {
2333 mutex_unlock(&module_mutex);
2334 return PTR_ERR(mod);
2337 /* Drop lock so they can recurse */
2338 mutex_unlock(&module_mutex);
2340 blocking_notifier_call_chain(&module_notify_list,
2341 MODULE_STATE_COMING, mod);
2343 /* Start the module */
2344 if (mod->init != NULL)
2345 ret = do_one_initcall(mod->init);
2346 if (ret < 0) {
2347 /* Init routine failed: abort. Try to protect us from
2348 buggy refcounters. */
2349 mod->state = MODULE_STATE_GOING;
2350 synchronize_sched();
2351 module_put(mod);
2352 blocking_notifier_call_chain(&module_notify_list,
2353 MODULE_STATE_GOING, mod);
2354 mutex_lock(&module_mutex);
2355 free_module(mod);
2356 mutex_unlock(&module_mutex);
2357 wake_up(&module_wq);
2358 return ret;
2360 if (ret > 0) {
2361 printk(KERN_WARNING "%s: '%s'->init suspiciously returned %d, "
2362 "it should follow 0/-E convention\n"
2363 KERN_WARNING "%s: loading module anyway...\n",
2364 __func__, mod->name, ret,
2365 __func__);
2366 dump_stack();
2369 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2370 mod->state = MODULE_STATE_LIVE;
2371 wake_up(&module_wq);
2372 blocking_notifier_call_chain(&module_notify_list,
2373 MODULE_STATE_LIVE, mod);
2375 mutex_lock(&module_mutex);
2376 /* Drop initial reference. */
2377 module_put(mod);
2378 module_free(mod, mod->module_init);
2379 mod->module_init = NULL;
2380 mod->init_size = 0;
2381 mod->init_text_size = 0;
2382 mutex_unlock(&module_mutex);
2384 return 0;
2387 static inline int within(unsigned long addr, void *start, unsigned long size)
2389 return ((void *)addr >= start && (void *)addr < start + size);
2392 #ifdef CONFIG_KALLSYMS
2394 * This ignores the intensely annoying "mapping symbols" found
2395 * in ARM ELF files: $a, $t and $d.
2397 static inline int is_arm_mapping_symbol(const char *str)
2399 return str[0] == '$' && strchr("atd", str[1])
2400 && (str[2] == '\0' || str[2] == '.');
2403 static const char *get_ksymbol(struct module *mod,
2404 unsigned long addr,
2405 unsigned long *size,
2406 unsigned long *offset)
2408 unsigned int i, best = 0;
2409 unsigned long nextval;
2411 /* At worse, next value is at end of module */
2412 if (within_module_init(addr, mod))
2413 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2414 else
2415 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2417 /* Scan for closest preceeding symbol, and next symbol. (ELF
2418 starts real symbols at 1). */
2419 for (i = 1; i < mod->num_symtab; i++) {
2420 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2421 continue;
2423 /* We ignore unnamed symbols: they're uninformative
2424 * and inserted at a whim. */
2425 if (mod->symtab[i].st_value <= addr
2426 && mod->symtab[i].st_value > mod->symtab[best].st_value
2427 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2428 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2429 best = i;
2430 if (mod->symtab[i].st_value > addr
2431 && mod->symtab[i].st_value < nextval
2432 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2433 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2434 nextval = mod->symtab[i].st_value;
2437 if (!best)
2438 return NULL;
2440 if (size)
2441 *size = nextval - mod->symtab[best].st_value;
2442 if (offset)
2443 *offset = addr - mod->symtab[best].st_value;
2444 return mod->strtab + mod->symtab[best].st_name;
2447 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2448 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2449 const char *module_address_lookup(unsigned long addr,
2450 unsigned long *size,
2451 unsigned long *offset,
2452 char **modname,
2453 char *namebuf)
2455 struct module *mod;
2456 const char *ret = NULL;
2458 preempt_disable();
2459 list_for_each_entry_rcu(mod, &modules, list) {
2460 if (within_module_init(addr, mod) ||
2461 within_module_core(addr, mod)) {
2462 if (modname)
2463 *modname = mod->name;
2464 ret = get_ksymbol(mod, addr, size, offset);
2465 break;
2468 /* Make a copy in here where it's safe */
2469 if (ret) {
2470 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2471 ret = namebuf;
2473 preempt_enable();
2474 return ret;
2477 int lookup_module_symbol_name(unsigned long addr, char *symname)
2479 struct module *mod;
2481 preempt_disable();
2482 list_for_each_entry_rcu(mod, &modules, list) {
2483 if (within_module_init(addr, mod) ||
2484 within_module_core(addr, mod)) {
2485 const char *sym;
2487 sym = get_ksymbol(mod, addr, NULL, NULL);
2488 if (!sym)
2489 goto out;
2490 strlcpy(symname, sym, KSYM_NAME_LEN);
2491 preempt_enable();
2492 return 0;
2495 out:
2496 preempt_enable();
2497 return -ERANGE;
2500 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2501 unsigned long *offset, char *modname, char *name)
2503 struct module *mod;
2505 preempt_disable();
2506 list_for_each_entry_rcu(mod, &modules, list) {
2507 if (within_module_init(addr, mod) ||
2508 within_module_core(addr, mod)) {
2509 const char *sym;
2511 sym = get_ksymbol(mod, addr, size, offset);
2512 if (!sym)
2513 goto out;
2514 if (modname)
2515 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2516 if (name)
2517 strlcpy(name, sym, KSYM_NAME_LEN);
2518 preempt_enable();
2519 return 0;
2522 out:
2523 preempt_enable();
2524 return -ERANGE;
2527 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2528 char *name, char *module_name, int *exported)
2530 struct module *mod;
2532 preempt_disable();
2533 list_for_each_entry_rcu(mod, &modules, list) {
2534 if (symnum < mod->num_symtab) {
2535 *value = mod->symtab[symnum].st_value;
2536 *type = mod->symtab[symnum].st_info;
2537 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2538 KSYM_NAME_LEN);
2539 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2540 *exported = is_exported(name, *value, mod);
2541 preempt_enable();
2542 return 0;
2544 symnum -= mod->num_symtab;
2546 preempt_enable();
2547 return -ERANGE;
2550 static unsigned long mod_find_symname(struct module *mod, const char *name)
2552 unsigned int i;
2554 for (i = 0; i < mod->num_symtab; i++)
2555 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2556 mod->symtab[i].st_info != 'U')
2557 return mod->symtab[i].st_value;
2558 return 0;
2561 /* Look for this name: can be of form module:name. */
2562 unsigned long module_kallsyms_lookup_name(const char *name)
2564 struct module *mod;
2565 char *colon;
2566 unsigned long ret = 0;
2568 /* Don't lock: we're in enough trouble already. */
2569 preempt_disable();
2570 if ((colon = strchr(name, ':')) != NULL) {
2571 *colon = '\0';
2572 if ((mod = find_module(name)) != NULL)
2573 ret = mod_find_symname(mod, colon+1);
2574 *colon = ':';
2575 } else {
2576 list_for_each_entry_rcu(mod, &modules, list)
2577 if ((ret = mod_find_symname(mod, name)) != 0)
2578 break;
2580 preempt_enable();
2581 return ret;
2583 #endif /* CONFIG_KALLSYMS */
2585 static char *module_flags(struct module *mod, char *buf)
2587 int bx = 0;
2589 if (mod->taints ||
2590 mod->state == MODULE_STATE_GOING ||
2591 mod->state == MODULE_STATE_COMING) {
2592 buf[bx++] = '(';
2593 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2594 buf[bx++] = 'P';
2595 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2596 buf[bx++] = 'F';
2597 if (mod->taints & (1 << TAINT_CRAP))
2598 buf[bx++] = 'C';
2600 * TAINT_FORCED_RMMOD: could be added.
2601 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2602 * apply to modules.
2605 /* Show a - for module-is-being-unloaded */
2606 if (mod->state == MODULE_STATE_GOING)
2607 buf[bx++] = '-';
2608 /* Show a + for module-is-being-loaded */
2609 if (mod->state == MODULE_STATE_COMING)
2610 buf[bx++] = '+';
2611 buf[bx++] = ')';
2613 buf[bx] = '\0';
2615 return buf;
2618 #ifdef CONFIG_PROC_FS
2619 /* Called by the /proc file system to return a list of modules. */
2620 static void *m_start(struct seq_file *m, loff_t *pos)
2622 mutex_lock(&module_mutex);
2623 return seq_list_start(&modules, *pos);
2626 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2628 return seq_list_next(p, &modules, pos);
2631 static void m_stop(struct seq_file *m, void *p)
2633 mutex_unlock(&module_mutex);
2636 static int m_show(struct seq_file *m, void *p)
2638 struct module *mod = list_entry(p, struct module, list);
2639 char buf[8];
2641 seq_printf(m, "%s %u",
2642 mod->name, mod->init_size + mod->core_size);
2643 print_unload_info(m, mod);
2645 /* Informative for users. */
2646 seq_printf(m, " %s",
2647 mod->state == MODULE_STATE_GOING ? "Unloading":
2648 mod->state == MODULE_STATE_COMING ? "Loading":
2649 "Live");
2650 /* Used by oprofile and other similar tools. */
2651 seq_printf(m, " 0x%p", mod->module_core);
2653 /* Taints info */
2654 if (mod->taints)
2655 seq_printf(m, " %s", module_flags(mod, buf));
2657 seq_printf(m, "\n");
2658 return 0;
2661 /* Format: modulename size refcount deps address
2663 Where refcount is a number or -, and deps is a comma-separated list
2664 of depends or -.
2666 static const struct seq_operations modules_op = {
2667 .start = m_start,
2668 .next = m_next,
2669 .stop = m_stop,
2670 .show = m_show
2673 static int modules_open(struct inode *inode, struct file *file)
2675 return seq_open(file, &modules_op);
2678 static const struct file_operations proc_modules_operations = {
2679 .open = modules_open,
2680 .read = seq_read,
2681 .llseek = seq_lseek,
2682 .release = seq_release,
2685 static int __init proc_modules_init(void)
2687 proc_create("modules", 0, NULL, &proc_modules_operations);
2688 return 0;
2690 module_init(proc_modules_init);
2691 #endif
2693 /* Given an address, look for it in the module exception tables. */
2694 const struct exception_table_entry *search_module_extables(unsigned long addr)
2696 const struct exception_table_entry *e = NULL;
2697 struct module *mod;
2699 preempt_disable();
2700 list_for_each_entry_rcu(mod, &modules, list) {
2701 if (mod->num_exentries == 0)
2702 continue;
2704 e = search_extable(mod->extable,
2705 mod->extable + mod->num_exentries - 1,
2706 addr);
2707 if (e)
2708 break;
2710 preempt_enable();
2712 /* Now, if we found one, we are running inside it now, hence
2713 we cannot unload the module, hence no refcnt needed. */
2714 return e;
2718 * Is this a valid module address?
2720 int is_module_address(unsigned long addr)
2722 struct module *mod;
2724 preempt_disable();
2726 list_for_each_entry_rcu(mod, &modules, list) {
2727 if (within_module_core(addr, mod)) {
2728 preempt_enable();
2729 return 1;
2733 preempt_enable();
2735 return 0;
2739 /* Is this a valid kernel address? */
2740 __notrace_funcgraph struct module *__module_text_address(unsigned long addr)
2742 struct module *mod;
2744 if (addr < module_addr_min || addr > module_addr_max)
2745 return NULL;
2747 list_for_each_entry_rcu(mod, &modules, list)
2748 if (within(addr, mod->module_init, mod->init_text_size)
2749 || within(addr, mod->module_core, mod->core_text_size))
2750 return mod;
2751 return NULL;
2754 struct module *module_text_address(unsigned long addr)
2756 struct module *mod;
2758 preempt_disable();
2759 mod = __module_text_address(addr);
2760 preempt_enable();
2762 return mod;
2765 /* Don't grab lock, we're oopsing. */
2766 void print_modules(void)
2768 struct module *mod;
2769 char buf[8];
2771 printk("Modules linked in:");
2772 /* Most callers should already have preempt disabled, but make sure */
2773 preempt_disable();
2774 list_for_each_entry_rcu(mod, &modules, list)
2775 printk(" %s%s", mod->name, module_flags(mod, buf));
2776 preempt_enable();
2777 if (last_unloaded_module[0])
2778 printk(" [last unloaded: %s]", last_unloaded_module);
2779 printk("\n");
2782 #ifdef CONFIG_MODVERSIONS
2783 /* Generate the signature for struct module here, too, for modversions. */
2784 void struct_module(struct module *mod) { return; }
2785 EXPORT_SYMBOL(struct_module);
2786 #endif
2788 #ifdef CONFIG_MARKERS
2789 void module_update_markers(void)
2791 struct module *mod;
2793 mutex_lock(&module_mutex);
2794 list_for_each_entry(mod, &modules, list)
2795 if (!mod->taints)
2796 marker_update_probe_range(mod->markers,
2797 mod->markers + mod->num_markers);
2798 mutex_unlock(&module_mutex);
2800 #endif
2802 #ifdef CONFIG_TRACEPOINTS
2803 void module_update_tracepoints(void)
2805 struct module *mod;
2807 mutex_lock(&module_mutex);
2808 list_for_each_entry(mod, &modules, list)
2809 if (!mod->taints)
2810 tracepoint_update_probe_range(mod->tracepoints,
2811 mod->tracepoints + mod->num_tracepoints);
2812 mutex_unlock(&module_mutex);
2816 * Returns 0 if current not found.
2817 * Returns 1 if current found.
2819 int module_get_iter_tracepoints(struct tracepoint_iter *iter)
2821 struct module *iter_mod;
2822 int found = 0;
2824 mutex_lock(&module_mutex);
2825 list_for_each_entry(iter_mod, &modules, list) {
2826 if (!iter_mod->taints) {
2828 * Sorted module list
2830 if (iter_mod < iter->module)
2831 continue;
2832 else if (iter_mod > iter->module)
2833 iter->tracepoint = NULL;
2834 found = tracepoint_get_iter_range(&iter->tracepoint,
2835 iter_mod->tracepoints,
2836 iter_mod->tracepoints
2837 + iter_mod->num_tracepoints);
2838 if (found) {
2839 iter->module = iter_mod;
2840 break;
2844 mutex_unlock(&module_mutex);
2845 return found;
2847 #endif