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mtdchar build fix
[linux-2.6/zen-sources.git] / kernel / module.c
blob33c04ad511750bc693410d9866b98dcfa6c2cb3d
1 /*
2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.
4
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.
9
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.
14
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
18 */
19 #include <linux/module.h>
20 #include <linux/moduleloader.h>
21 #include <linux/init.h>
22 #include <linux/kallsyms.h>
23 #include <linux/kernel.h>
24 #include <linux/slab.h>
25 #include <linux/vmalloc.h>
26 #include <linux/elf.h>
27 #include <linux/seq_file.h>
28 #include <linux/syscalls.h>
29 #include <linux/fcntl.h>
30 #include <linux/rcupdate.h>
31 #include <linux/capability.h>
32 #include <linux/cpu.h>
33 #include <linux/moduleparam.h>
34 #include <linux/errno.h>
35 #include <linux/err.h>
36 #include <linux/vermagic.h>
37 #include <linux/notifier.h>
38 #include <linux/sched.h>
39 #include <linux/stop_machine.h>
40 #include <linux/device.h>
41 #include <linux/string.h>
42 #include <linux/mutex.h>
43 #include <linux/unwind.h>
44 #include <asm/uaccess.h>
45 #include <asm/semaphore.h>
46 #include <asm/cacheflush.h>
47 #include <linux/license.h>
48
49 extern int module_sysfs_initialized;
50
51 #if 0
52 #define DEBUGP printk
53 #else
54 #define DEBUGP(fmt , a...)
55 #endif
56
57 #ifndef ARCH_SHF_SMALL
58 #define ARCH_SHF_SMALL 0
59 #endif
60
61 /* If this is set, the section belongs in the init part of the module */
62 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
63
64 /* List of modules, protected by module_mutex or preempt_disable
65 * (add/delete uses stop_machine). */
66 static DEFINE_MUTEX(module_mutex);
67 static LIST_HEAD(modules);
68
69 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
70
71 int register_module_notifier(struct notifier_block * nb)
72 {
73 return blocking_notifier_chain_register(&module_notify_list, nb);
74 }
75 EXPORT_SYMBOL(register_module_notifier);
76
77 int unregister_module_notifier(struct notifier_block * nb)
78 {
79 return blocking_notifier_chain_unregister(&module_notify_list, nb);
80 }
81 EXPORT_SYMBOL(unregister_module_notifier);
82
83 /* We require a truly strong try_module_get() */
84 static inline int strong_try_module_get(struct module *mod)
85 {
86 if (mod && mod->state == MODULE_STATE_COMING)
87 return 0;
88 return try_module_get(mod);
89 }
90
91 static inline void add_taint_module(struct module *mod, unsigned flag)
92 {
93 add_taint(flag);
94 mod->taints |= flag;
95 }
96
97 /*
98 * A thread that wants to hold a reference to a module only while it
99 * is running can call this to safely exit. nfsd and lockd use this.
100 */
101 void __module_put_and_exit(struct module *mod, long code)
102 {
103 module_put(mod);
104 do_exit(code);
105 }
106 EXPORT_SYMBOL(__module_put_and_exit);
107
108 /* Find a module section: 0 means not found. */
109 static unsigned int find_sec(Elf_Ehdr *hdr,
110 Elf_Shdr *sechdrs,
111 const char *secstrings,
112 const char *name)
113 {
114 unsigned int i;
115
116 for (i = 1; i < hdr->e_shnum; i++)
117 /* Alloc bit cleared means "ignore it." */
118 if ((sechdrs[i].sh_flags & SHF_ALLOC)
119 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
120 return i;
121 return 0;
122 }
123
124 /* Provided by the linker */
125 extern const struct kernel_symbol __start___ksymtab[];
126 extern const struct kernel_symbol __stop___ksymtab[];
127 extern const struct kernel_symbol __start___ksymtab_gpl[];
128 extern const struct kernel_symbol __stop___ksymtab_gpl[];
129 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
130 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
131 extern const struct kernel_symbol __start___ksymtab_unused[];
132 extern const struct kernel_symbol __stop___ksymtab_unused[];
133 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
134 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
135 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
136 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
137 extern const unsigned long __start___kcrctab[];
138 extern const unsigned long __start___kcrctab_gpl[];
139 extern const unsigned long __start___kcrctab_gpl_future[];
140 extern const unsigned long __start___kcrctab_unused[];
141 extern const unsigned long __start___kcrctab_unused_gpl[];
142
143 #ifndef CONFIG_MODVERSIONS
144 #define symversion(base, idx) NULL
145 #else
146 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
147 #endif
148
149 /* lookup symbol in given range of kernel_symbols */
150 static const struct kernel_symbol *lookup_symbol(const char *name,
151 const struct kernel_symbol *start,
152 const struct kernel_symbol *stop)
153 {
154 const struct kernel_symbol *ks = start;
155 for (; ks < stop; ks++)
156 if (strcmp(ks->name, name) == 0)
157 return ks;
158 return NULL;
159 }
160
161 static void printk_unused_warning(const char *name)
162 {
163 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
164 "however this module is using it.\n", name);
165 printk(KERN_WARNING "This symbol will go away in the future.\n");
166 printk(KERN_WARNING "Please evalute if this is the right api to use, "
167 "and if it really is, submit a report the linux kernel "
168 "mailinglist together with submitting your code for "
169 "inclusion.\n");
170 }
171
172 /* Find a symbol, return value, crc and module which owns it */
173 static unsigned long __find_symbol(const char *name,
174 struct module **owner,
175 const unsigned long **crc,
176 int gplok)
177 {
178 struct module *mod;
179 const struct kernel_symbol *ks;
180
181 /* Core kernel first. */
182 *owner = NULL;
183 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
184 if (ks) {
185 *crc = symversion(__start___kcrctab, (ks - __start___ksymtab));
186 return ks->value;
187 }
188 if (gplok) {
189 ks = lookup_symbol(name, __start___ksymtab_gpl,
190 __stop___ksymtab_gpl);
191 if (ks) {
192 *crc = symversion(__start___kcrctab_gpl,
193 (ks - __start___ksymtab_gpl));
194 return ks->value;
195 }
196 }
197 ks = lookup_symbol(name, __start___ksymtab_gpl_future,
198 __stop___ksymtab_gpl_future);
199 if (ks) {
200 if (!gplok) {
201 printk(KERN_WARNING "Symbol %s is being used "
202 "by a non-GPL module, which will not "
203 "be allowed in the future\n", name);
204 printk(KERN_WARNING "Please see the file "
205 "Documentation/feature-removal-schedule.txt "
206 "in the kernel source tree for more "
207 "details.\n");
208 }
209 *crc = symversion(__start___kcrctab_gpl_future,
210 (ks - __start___ksymtab_gpl_future));
211 return ks->value;
212 }
213
214 ks = lookup_symbol(name, __start___ksymtab_unused,
215 __stop___ksymtab_unused);
216 if (ks) {
217 printk_unused_warning(name);
218 *crc = symversion(__start___kcrctab_unused,
219 (ks - __start___ksymtab_unused));
220 return ks->value;
221 }
222
223 if (gplok)
224 ks = lookup_symbol(name, __start___ksymtab_unused_gpl,
225 __stop___ksymtab_unused_gpl);
226 if (ks) {
227 printk_unused_warning(name);
228 *crc = symversion(__start___kcrctab_unused_gpl,
229 (ks - __start___ksymtab_unused_gpl));
230 return ks->value;
231 }
232
233 /* Now try modules. */
234 list_for_each_entry(mod, &modules, list) {
235 *owner = mod;
236 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
237 if (ks) {
238 *crc = symversion(mod->crcs, (ks - mod->syms));
239 return ks->value;
240 }
241
242 if (gplok) {
243 ks = lookup_symbol(name, mod->gpl_syms,
244 mod->gpl_syms + mod->num_gpl_syms);
245 if (ks) {
246 *crc = symversion(mod->gpl_crcs,
247 (ks - mod->gpl_syms));
248 return ks->value;
249 }
250 }
251 ks = lookup_symbol(name, mod->unused_syms, mod->unused_syms + mod->num_unused_syms);
252 if (ks) {
253 printk_unused_warning(name);
254 *crc = symversion(mod->unused_crcs, (ks - mod->unused_syms));
255 return ks->value;
256 }
257
258 if (gplok) {
259 ks = lookup_symbol(name, mod->unused_gpl_syms,
260 mod->unused_gpl_syms + mod->num_unused_gpl_syms);
261 if (ks) {
262 printk_unused_warning(name);
263 *crc = symversion(mod->unused_gpl_crcs,
264 (ks - mod->unused_gpl_syms));
265 return ks->value;
266 }
267 }
268 ks = lookup_symbol(name, mod->gpl_future_syms,
269 (mod->gpl_future_syms +
270 mod->num_gpl_future_syms));
271 if (ks) {
272 if (!gplok) {
273 printk(KERN_WARNING "Symbol %s is being used "
274 "by a non-GPL module, which will not "
275 "be allowed in the future\n", name);
276 printk(KERN_WARNING "Please see the file "
277 "Documentation/feature-removal-schedule.txt "
278 "in the kernel source tree for more "
279 "details.\n");
280 }
281 *crc = symversion(mod->gpl_future_crcs,
282 (ks - mod->gpl_future_syms));
283 return ks->value;
284 }
285 }
286 DEBUGP("Failed to find symbol %s\n", name);
287 return 0;
288 }
289
290 /* Search for module by name: must hold module_mutex. */
291 static struct module *find_module(const char *name)
292 {
293 struct module *mod;
294
295 list_for_each_entry(mod, &modules, list) {
296 if (strcmp(mod->name, name) == 0)
297 return mod;
298 }
299 return NULL;
300 }
301
302 #ifdef CONFIG_SMP
303 /* Number of blocks used and allocated. */
304 static unsigned int pcpu_num_used, pcpu_num_allocated;
305 /* Size of each block. -ve means used. */
306 static int *pcpu_size;
307
308 static int split_block(unsigned int i, unsigned short size)
309 {
310 /* Reallocation required? */
311 if (pcpu_num_used + 1 > pcpu_num_allocated) {
312 int *new;
313
314 new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2,
315 GFP_KERNEL);
316 if (!new)
317 return 0;
318
319 pcpu_num_allocated *= 2;
320 pcpu_size = new;
321 }
322
323 /* Insert a new subblock */
324 memmove(&pcpu_size[i+1], &pcpu_size[i],
325 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
326 pcpu_num_used++;
327
328 pcpu_size[i+1] -= size;
329 pcpu_size[i] = size;
330 return 1;
331 }
332
333 static inline unsigned int block_size(int val)
334 {
335 if (val < 0)
336 return -val;
337 return val;
338 }
339
340 /* Created by linker magic */
341 extern char __per_cpu_start[], __per_cpu_end[];
342
343 static void *percpu_modalloc(unsigned long size, unsigned long align,
344 const char *name)
345 {
346 unsigned long extra;
347 unsigned int i;
348 void *ptr;
349
350 if (align > PAGE_SIZE) {
351 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
352 name, align, PAGE_SIZE);
353 align = PAGE_SIZE;
354 }
355
356 ptr = __per_cpu_start;
357 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
358 /* Extra for alignment requirement. */
359 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
360 BUG_ON(i == 0 && extra != 0);
361
362 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
363 continue;
364
365 /* Transfer extra to previous block. */
366 if (pcpu_size[i-1] < 0)
367 pcpu_size[i-1] -= extra;
368 else
369 pcpu_size[i-1] += extra;
370 pcpu_size[i] -= extra;
371 ptr += extra;
372
373 /* Split block if warranted */
374 if (pcpu_size[i] - size > sizeof(unsigned long))
375 if (!split_block(i, size))
376 return NULL;
377
378 /* Mark allocated */
379 pcpu_size[i] = -pcpu_size[i];
380 return ptr;
381 }
382
383 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
384 size);
385 return NULL;
386 }
387
388 static void percpu_modfree(void *freeme)
389 {
390 unsigned int i;
391 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
392
393 /* First entry is core kernel percpu data. */
394 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
395 if (ptr == freeme) {
396 pcpu_size[i] = -pcpu_size[i];
397 goto free;
398 }
399 }
400 BUG();
401
402 free:
403 /* Merge with previous? */
404 if (pcpu_size[i-1] >= 0) {
405 pcpu_size[i-1] += pcpu_size[i];
406 pcpu_num_used--;
407 memmove(&pcpu_size[i], &pcpu_size[i+1],
408 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
409 i--;
410 }
411 /* Merge with next? */
412 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
413 pcpu_size[i] += pcpu_size[i+1];
414 pcpu_num_used--;
415 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
416 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
417 }
418 }
419
420 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
421 Elf_Shdr *sechdrs,
422 const char *secstrings)
423 {
424 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
425 }
426
427 static int percpu_modinit(void)
428 {
429 pcpu_num_used = 2;
430 pcpu_num_allocated = 2;
431 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
432 GFP_KERNEL);
433 /* Static in-kernel percpu data (used). */
434 pcpu_size[0] = -(__per_cpu_end-__per_cpu_start);
435 /* Free room. */
436 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
437 if (pcpu_size[1] < 0) {
438 printk(KERN_ERR "No per-cpu room for modules.\n");
439 pcpu_num_used = 1;
440 }
441
442 return 0;
443 }
444 __initcall(percpu_modinit);
445 #else /* ... !CONFIG_SMP */
446 static inline void *percpu_modalloc(unsigned long size, unsigned long align,
447 const char *name)
448 {
449 return NULL;
450 }
451 static inline void percpu_modfree(void *pcpuptr)
452 {
453 BUG();
454 }
455 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
456 Elf_Shdr *sechdrs,
457 const char *secstrings)
458 {
459 return 0;
460 }
461 static inline void percpu_modcopy(void *pcpudst, const void *src,
462 unsigned long size)
463 {
464 /* pcpusec should be 0, and size of that section should be 0. */
465 BUG_ON(size != 0);
466 }
467 #endif /* CONFIG_SMP */
468
469 #define MODINFO_ATTR(field) \
470 static void setup_modinfo_##field(struct module *mod, const char *s) \
471 { \
472 mod->field = kstrdup(s, GFP_KERNEL); \
473 } \
474 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
475 struct module *mod, char *buffer) \
476 { \
477 return sprintf(buffer, "%s\n", mod->field); \
478 } \
479 static int modinfo_##field##_exists(struct module *mod) \
480 { \
481 return mod->field != NULL; \
482 } \
483 static void free_modinfo_##field(struct module *mod) \
484 { \
485 kfree(mod->field); \
486 mod->field = NULL; \
487 } \
488 static struct module_attribute modinfo_##field = { \
489 .attr = { .name = __stringify(field), .mode = 0444 }, \
490 .show = show_modinfo_##field, \
491 .setup = setup_modinfo_##field, \
492 .test = modinfo_##field##_exists, \
493 .free = free_modinfo_##field, \
494 };
495
496 MODINFO_ATTR(version);
497 MODINFO_ATTR(srcversion);
498
499 #ifdef CONFIG_MODULE_UNLOAD
500 /* Init the unload section of the module. */
501 static void module_unload_init(struct module *mod)
502 {
503 unsigned int i;
504
505 INIT_LIST_HEAD(&mod->modules_which_use_me);
506 for (i = 0; i < NR_CPUS; i++)
507 local_set(&mod->ref[i].count, 0);
508 /* Hold reference count during initialization. */
509 local_set(&mod->ref[raw_smp_processor_id()].count, 1);
510 /* Backwards compatibility macros put refcount during init. */
511 mod->waiter = current;
512 }
513
514 /* modules using other modules */
515 struct module_use
516 {
517 struct list_head list;
518 struct module *module_which_uses;
519 };
520
521 /* Does a already use b? */
522 static int already_uses(struct module *a, struct module *b)
523 {
524 struct module_use *use;
525
526 list_for_each_entry(use, &b->modules_which_use_me, list) {
527 if (use->module_which_uses == a) {
528 DEBUGP("%s uses %s!\n", a->name, b->name);
529 return 1;
530 }
531 }
532 DEBUGP("%s does not use %s!\n", a->name, b->name);
533 return 0;
534 }
535
536 /* Module a uses b */
537 static int use_module(struct module *a, struct module *b)
538 {
539 struct module_use *use;
540 int no_warn;
541
542 if (b == NULL || already_uses(a, b)) return 1;
543
544 if (!strong_try_module_get(b))
545 return 0;
546
547 DEBUGP("Allocating new usage for %s.\n", a->name);
548 use = kmalloc(sizeof(*use), GFP_ATOMIC);
549 if (!use) {
550 printk("%s: out of memory loading\n", a->name);
551 module_put(b);
552 return 0;
553 }
554
555 use->module_which_uses = a;
556 list_add(&use->list, &b->modules_which_use_me);
557 no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
558 return 1;
559 }
560
561 /* Clear the unload stuff of the module. */
562 static void module_unload_free(struct module *mod)
563 {
564 struct module *i;
565
566 list_for_each_entry(i, &modules, list) {
567 struct module_use *use;
568
569 list_for_each_entry(use, &i->modules_which_use_me, list) {
570 if (use->module_which_uses == mod) {
571 DEBUGP("%s unusing %s\n", mod->name, i->name);
572 module_put(i);
573 list_del(&use->list);
574 kfree(use);
575 sysfs_remove_link(i->holders_dir, mod->name);
576 /* There can be at most one match. */
577 break;
578 }
579 }
580 }
581 }
582
583 #ifdef CONFIG_MODULE_FORCE_UNLOAD
584 static inline int try_force_unload(unsigned int flags)
585 {
586 int ret = (flags & O_TRUNC);
587 if (ret)
588 add_taint(TAINT_FORCED_RMMOD);
589 return ret;
590 }
591 #else
592 static inline int try_force_unload(unsigned int flags)
593 {
594 return 0;
595 }
596 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
597
598 struct stopref
599 {
600 struct module *mod;
601 int flags;
602 int *forced;
603 };
604
605 /* Whole machine is stopped with interrupts off when this runs. */
606 static int __try_stop_module(void *_sref)
607 {
608 struct stopref *sref = _sref;
609
610 /* If it's not unused, quit unless we are told to block. */
611 if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
612 if (!(*sref->forced = try_force_unload(sref->flags)))
613 return -EWOULDBLOCK;
614 }
615
616 /* Mark it as dying. */
617 sref->mod->state = MODULE_STATE_GOING;
618 return 0;
619 }
620
621 static int try_stop_module(struct module *mod, int flags, int *forced)
622 {
623 struct stopref sref = { mod, flags, forced };
624
625 return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
626 }
627
628 unsigned int module_refcount(struct module *mod)
629 {
630 unsigned int i, total = 0;
631
632 for (i = 0; i < NR_CPUS; i++)
633 total += local_read(&mod->ref[i].count);
634 return total;
635 }
636 EXPORT_SYMBOL(module_refcount);
637
638 /* This exists whether we can unload or not */
639 static void free_module(struct module *mod);
640
641 static void wait_for_zero_refcount(struct module *mod)
642 {
643 /* Since we might sleep for some time, drop the semaphore first */
644 mutex_unlock(&module_mutex);
645 for (;;) {
646 DEBUGP("Looking at refcount...\n");
647 set_current_state(TASK_UNINTERRUPTIBLE);
648 if (module_refcount(mod) == 0)
649 break;
650 schedule();
651 }
652 current->state = TASK_RUNNING;
653 mutex_lock(&module_mutex);
654 }
655
656 asmlinkage long
657 sys_delete_module(const char __user *name_user, unsigned int flags)
658 {
659 struct module *mod;
660 char name[MODULE_NAME_LEN];
661 int ret, forced = 0;
662
663 if (!capable(CAP_SYS_MODULE))
664 return -EPERM;
665
666 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
667 return -EFAULT;
668 name[MODULE_NAME_LEN-1] = '\0';
669
670 if (mutex_lock_interruptible(&module_mutex) != 0)
671 return -EINTR;
672
673 mod = find_module(name);
674 if (!mod) {
675 ret = -ENOENT;
676 goto out;
677 }
678
679 if (!list_empty(&mod->modules_which_use_me)) {
680 /* Other modules depend on us: get rid of them first. */
681 ret = -EWOULDBLOCK;
682 goto out;
683 }
684
685 /* Doing init or already dying? */
686 if (mod->state != MODULE_STATE_LIVE) {
687 /* FIXME: if (force), slam module count and wake up
688 waiter --RR */
689 DEBUGP("%s already dying\n", mod->name);
690 ret = -EBUSY;
691 goto out;
692 }
693
694 /* If it has an init func, it must have an exit func to unload */
695 if ((mod->init != NULL && mod->exit == NULL)
696 || mod->unsafe) {
697 forced = try_force_unload(flags);
698 if (!forced) {
699 /* This module can't be removed */
700 ret = -EBUSY;
701 goto out;
702 }
703 }
704
705 /* Set this up before setting mod->state */
706 mod->waiter = current;
707
708 /* Stop the machine so refcounts can't move and disable module. */
709 ret = try_stop_module(mod, flags, &forced);
710 if (ret != 0)
711 goto out;
712
713 /* Never wait if forced. */
714 if (!forced && module_refcount(mod) != 0)
715 wait_for_zero_refcount(mod);
716
717 /* Final destruction now noone is using it. */
718 if (mod->exit != NULL) {
719 mutex_unlock(&module_mutex);
720 mod->exit();
721 mutex_lock(&module_mutex);
722 }
723 free_module(mod);
724
725 out:
726 mutex_unlock(&module_mutex);
727 return ret;
728 }
729
730 static void print_unload_info(struct seq_file *m, struct module *mod)
731 {
732 struct module_use *use;
733 int printed_something = 0;
734
735 seq_printf(m, " %u ", module_refcount(mod));
736
737 /* Always include a trailing , so userspace can differentiate
738 between this and the old multi-field proc format. */
739 list_for_each_entry(use, &mod->modules_which_use_me, list) {
740 printed_something = 1;
741 seq_printf(m, "%s,", use->module_which_uses->name);
742 }
743
744 if (mod->unsafe) {
745 printed_something = 1;
746 seq_printf(m, "[unsafe],");
747 }
748
749 if (mod->init != NULL && mod->exit == NULL) {
750 printed_something = 1;
751 seq_printf(m, "[permanent],");
752 }
753
754 if (!printed_something)
755 seq_printf(m, "-");
756 }
757
758 void __symbol_put(const char *symbol)
759 {
760 struct module *owner;
761 const unsigned long *crc;
762
763 preempt_disable();
764 if (!__find_symbol(symbol, &owner, &crc, 1))
765 BUG();
766 module_put(owner);
767 preempt_enable();
768 }
769 EXPORT_SYMBOL(__symbol_put);
770
771 void symbol_put_addr(void *addr)
772 {
773 struct module *modaddr;
774
775 if (core_kernel_text((unsigned long)addr))
776 return;
777
778 if (!(modaddr = module_text_address((unsigned long)addr)))
779 BUG();
780 module_put(modaddr);
781 }
782 EXPORT_SYMBOL_GPL(symbol_put_addr);
783
784 static ssize_t show_refcnt(struct module_attribute *mattr,
785 struct module *mod, char *buffer)
786 {
787 /* sysfs holds a reference */
788 return sprintf(buffer, "%u\n", module_refcount(mod)-1);
789 }
790
791 static struct module_attribute refcnt = {
792 .attr = { .name = "refcnt", .mode = 0444 },
793 .show = show_refcnt,
794 };
795
796 void module_put(struct module *module)
797 {
798 if (module) {
799 unsigned int cpu = get_cpu();
800 local_dec(&module->ref[cpu].count);
801 /* Maybe they're waiting for us to drop reference? */
802 if (unlikely(!module_is_live(module)))
803 wake_up_process(module->waiter);
804 put_cpu();
805 }
806 }
807 EXPORT_SYMBOL(module_put);
808
809 #else /* !CONFIG_MODULE_UNLOAD */
810 static void print_unload_info(struct seq_file *m, struct module *mod)
811 {
812 /* We don't know the usage count, or what modules are using. */
813 seq_printf(m, " - -");
814 }
815
816 static inline void module_unload_free(struct module *mod)
817 {
818 }
819
820 static inline int use_module(struct module *a, struct module *b)
821 {
822 return strong_try_module_get(b);
823 }
824
825 static inline void module_unload_init(struct module *mod)
826 {
827 }
828 #endif /* CONFIG_MODULE_UNLOAD */
829
830 static ssize_t show_initstate(struct module_attribute *mattr,
831 struct module *mod, char *buffer)
832 {
833 const char *state = "unknown";
834
835 switch (mod->state) {
836 case MODULE_STATE_LIVE:
837 state = "live";
838 break;
839 case MODULE_STATE_COMING:
840 state = "coming";
841 break;
842 case MODULE_STATE_GOING:
843 state = "going";
844 break;
845 }
846 return sprintf(buffer, "%s\n", state);
847 }
848
849 static struct module_attribute initstate = {
850 .attr = { .name = "initstate", .mode = 0444 },
851 .show = show_initstate,
852 };
853
854 static struct module_attribute *modinfo_attrs[] = {
855 &modinfo_version,
856 &modinfo_srcversion,
857 &initstate,
858 #ifdef CONFIG_MODULE_UNLOAD
859 &refcnt,
860 #endif
861 NULL,
862 };
863
864 static const char vermagic[] = VERMAGIC_STRING;
865
866 #ifdef CONFIG_MODVERSIONS
867 static int check_version(Elf_Shdr *sechdrs,
868 unsigned int versindex,
869 const char *symname,
870 struct module *mod,
871 const unsigned long *crc)
872 {
873 unsigned int i, num_versions;
874 struct modversion_info *versions;
875
876 /* Exporting module didn't supply crcs? OK, we're already tainted. */
877 if (!crc)
878 return 1;
879
880 versions = (void *) sechdrs[versindex].sh_addr;
881 num_versions = sechdrs[versindex].sh_size
882 / sizeof(struct modversion_info);
883
884 for (i = 0; i < num_versions; i++) {
885 if (strcmp(versions[i].name, symname) != 0)
886 continue;
887
888 if (versions[i].crc == *crc)
889 return 1;
890 printk("%s: disagrees about version of symbol %s\n",
891 mod->name, symname);
892 DEBUGP("Found checksum %lX vs module %lX\n",
893 *crc, versions[i].crc);
894 return 0;
895 }
896 /* Not in module's version table. OK, but that taints the kernel. */
897 if (!(tainted & TAINT_FORCED_MODULE))
898 printk("%s: no version for \"%s\" found: kernel tainted.\n",
899 mod->name, symname);
900 add_taint_module(mod, TAINT_FORCED_MODULE);
901 return 1;
902 }
903
904 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
905 unsigned int versindex,
906 struct module *mod)
907 {
908 const unsigned long *crc;
909 struct module *owner;
910
911 if (!__find_symbol("struct_module", &owner, &crc, 1))
912 BUG();
913 return check_version(sechdrs, versindex, "struct_module", mod,
914 crc);
915 }
916
917 /* First part is kernel version, which we ignore. */
918 static inline int same_magic(const char *amagic, const char *bmagic)
919 {
920 amagic += strcspn(amagic, " ");
921 bmagic += strcspn(bmagic, " ");
922 return strcmp(amagic, bmagic) == 0;
923 }
924 #else
925 static inline int check_version(Elf_Shdr *sechdrs,
926 unsigned int versindex,
927 const char *symname,
928 struct module *mod,
929 const unsigned long *crc)
930 {
931 return 1;
932 }
933
934 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
935 unsigned int versindex,
936 struct module *mod)
937 {
938 return 1;
939 }
940
941 static inline int same_magic(const char *amagic, const char *bmagic)
942 {
943 return strcmp(amagic, bmagic) == 0;
944 }
945 #endif /* CONFIG_MODVERSIONS */
946
947 /* Resolve a symbol for this module. I.e. if we find one, record usage.
948 Must be holding module_mutex. */
949 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
950 unsigned int versindex,
951 const char *name,
952 struct module *mod)
953 {
954 struct module *owner;
955 unsigned long ret;
956 const unsigned long *crc;
957
958 ret = __find_symbol(name, &owner, &crc,
959 !(mod->taints & TAINT_PROPRIETARY_MODULE));
960 if (ret) {
961 /* use_module can fail due to OOM, or module unloading */
962 if (!check_version(sechdrs, versindex, name, mod, crc) ||
963 !use_module(mod, owner))
964 ret = 0;
965 }
966 return ret;
967 }
968
969
970 /*
971 * /sys/module/foo/sections stuff
972 * J. Corbet <corbet@lwn.net>
973 */
974 #ifdef CONFIG_KALLSYMS
975 static ssize_t module_sect_show(struct module_attribute *mattr,
976 struct module *mod, char *buf)
977 {
978 struct module_sect_attr *sattr =
979 container_of(mattr, struct module_sect_attr, mattr);
980 return sprintf(buf, "0x%lx\n", sattr->address);
981 }
982
983 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
984 {
985 int section;
986
987 for (section = 0; section < sect_attrs->nsections; section++)
988 kfree(sect_attrs->attrs[section].name);
989 kfree(sect_attrs);
990 }
991
992 static void add_sect_attrs(struct module *mod, unsigned int nsect,
993 char *secstrings, Elf_Shdr *sechdrs)
994 {
995 unsigned int nloaded = 0, i, size[2];
996 struct module_sect_attrs *sect_attrs;
997 struct module_sect_attr *sattr;
998 struct attribute **gattr;
999
1000 /* Count loaded sections and allocate structures */
1001 for (i = 0; i < nsect; i++)
1002 if (sechdrs[i].sh_flags & SHF_ALLOC)
1003 nloaded++;
1004 size[0] = ALIGN(sizeof(*sect_attrs)
1005 + nloaded * sizeof(sect_attrs->attrs[0]),
1006 sizeof(sect_attrs->grp.attrs[0]));
1007 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1008 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1009 if (sect_attrs == NULL)
1010 return;
1011
1012 /* Setup section attributes. */
1013 sect_attrs->grp.name = "sections";
1014 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1015
1016 sect_attrs->nsections = 0;
1017 sattr = &sect_attrs->attrs[0];
1018 gattr = &sect_attrs->grp.attrs[0];
1019 for (i = 0; i < nsect; i++) {
1020 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1021 continue;
1022 sattr->address = sechdrs[i].sh_addr;
1023 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1024 GFP_KERNEL);
1025 if (sattr->name == NULL)
1026 goto out;
1027 sect_attrs->nsections++;
1028 sattr->mattr.show = module_sect_show;
1029 sattr->mattr.store = NULL;
1030 sattr->mattr.attr.name = sattr->name;
1031 sattr->mattr.attr.mode = S_IRUGO;
1032 *(gattr++) = &(sattr++)->mattr.attr;
1033 }
1034 *gattr = NULL;
1035
1036 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1037 goto out;
1038
1039 mod->sect_attrs = sect_attrs;
1040 return;
1041 out:
1042 free_sect_attrs(sect_attrs);
1043 }
1044
1045 static void remove_sect_attrs(struct module *mod)
1046 {
1047 if (mod->sect_attrs) {
1048 sysfs_remove_group(&mod->mkobj.kobj,
1049 &mod->sect_attrs->grp);
1050 /* We are positive that no one is using any sect attrs
1051 * at this point. Deallocate immediately. */
1052 free_sect_attrs(mod->sect_attrs);
1053 mod->sect_attrs = NULL;
1054 }
1055 }
1056
1057 #else
1058
1059 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1060 char *sectstrings, Elf_Shdr *sechdrs)
1061 {
1062 }
1063
1064 static inline void remove_sect_attrs(struct module *mod)
1065 {
1066 }
1067 #endif /* CONFIG_KALLSYMS */
1068
1069 #ifdef CONFIG_SYSFS
1070 int module_add_modinfo_attrs(struct module *mod)
1071 {
1072 struct module_attribute *attr;
1073 struct module_attribute *temp_attr;
1074 int error = 0;
1075 int i;
1076
1077 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1078 (ARRAY_SIZE(modinfo_attrs) + 1)),
1079 GFP_KERNEL);
1080 if (!mod->modinfo_attrs)
1081 return -ENOMEM;
1082
1083 temp_attr = mod->modinfo_attrs;
1084 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1085 if (!attr->test ||
1086 (attr->test && attr->test(mod))) {
1087 memcpy(temp_attr, attr, sizeof(*temp_attr));
1088 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1089 ++temp_attr;
1090 }
1091 }
1092 return error;
1093 }
1094
1095 void module_remove_modinfo_attrs(struct module *mod)
1096 {
1097 struct module_attribute *attr;
1098 int i;
1099
1100 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1101 /* pick a field to test for end of list */
1102 if (!attr->attr.name)
1103 break;
1104 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1105 if (attr->free)
1106 attr->free(mod);
1107 }
1108 kfree(mod->modinfo_attrs);
1109 }
1110 #endif
1111
1112 #ifdef CONFIG_SYSFS
1113 int mod_sysfs_init(struct module *mod)
1114 {
1115 int err;
1116
1117 if (!module_sysfs_initialized) {
1118 printk(KERN_ERR "%s: module sysfs not initialized\n",
1119 mod->name);
1120 err = -EINVAL;
1121 goto out;
1122 }
1123 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1124 err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name);
1125 if (err)
1126 goto out;
1127 kobj_set_kset_s(&mod->mkobj, module_subsys);
1128 mod->mkobj.mod = mod;
1129
1130 kobject_init(&mod->mkobj.kobj);
1131
1132 out:
1133 return err;
1134 }
1135
1136 int mod_sysfs_setup(struct module *mod,
1137 struct kernel_param *kparam,
1138 unsigned int num_params)
1139 {
1140 int err;
1141
1142 /* delay uevent until full sysfs population */
1143 err = kobject_add(&mod->mkobj.kobj);
1144 if (err)
1145 goto out;
1146
1147 mod->holders_dir = kobject_add_dir(&mod->mkobj.kobj, "holders");
1148 if (!mod->holders_dir) {
1149 err = -ENOMEM;
1150 goto out_unreg;
1151 }
1152
1153 err = module_param_sysfs_setup(mod, kparam, num_params);
1154 if (err)
1155 goto out_unreg_holders;
1156
1157 err = module_add_modinfo_attrs(mod);
1158 if (err)
1159 goto out_unreg_param;
1160
1161 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1162 return 0;
1163
1164 out_unreg_param:
1165 module_param_sysfs_remove(mod);
1166 out_unreg_holders:
1167 kobject_unregister(mod->holders_dir);
1168 out_unreg:
1169 kobject_del(&mod->mkobj.kobj);
1170 kobject_put(&mod->mkobj.kobj);
1171 out:
1172 return err;
1173 }
1174 #endif
1175
1176 static void mod_kobject_remove(struct module *mod)
1177 {
1178 module_remove_modinfo_attrs(mod);
1179 module_param_sysfs_remove(mod);
1180 kobject_unregister(mod->mkobj.drivers_dir);
1181 kobject_unregister(mod->holders_dir);
1182 kobject_unregister(&mod->mkobj.kobj);
1183 }
1184
1185 /*
1186 * unlink the module with the whole machine is stopped with interrupts off
1187 * - this defends against kallsyms not taking locks
1188 */
1189 static int __unlink_module(void *_mod)
1190 {
1191 struct module *mod = _mod;
1192 list_del(&mod->list);
1193 return 0;
1194 }
1195
1196 /* Free a module, remove from lists, etc (must hold module_mutex). */
1197 static void free_module(struct module *mod)
1198 {
1199 /* Delete from various lists */
1200 stop_machine_run(__unlink_module, mod, NR_CPUS);
1201 remove_sect_attrs(mod);
1202 mod_kobject_remove(mod);
1203
1204 unwind_remove_table(mod->unwind_info, 0);
1205
1206 /* Arch-specific cleanup. */
1207 module_arch_cleanup(mod);
1208
1209 /* Module unload stuff */
1210 module_unload_free(mod);
1211
1212 /* This may be NULL, but that's OK */
1213 module_free(mod, mod->module_init);
1214 kfree(mod->args);
1215 if (mod->percpu)
1216 percpu_modfree(mod->percpu);
1217
1218 /* Free lock-classes: */
1219 lockdep_free_key_range(mod->module_core, mod->core_size);
1220
1221 /* Finally, free the core (containing the module structure) */
1222 module_free(mod, mod->module_core);
1223 }
1224
1225 void *__symbol_get(const char *symbol)
1226 {
1227 struct module *owner;
1228 unsigned long value;
1229 const unsigned long *crc;
1230
1231 preempt_disable();
1232 value = __find_symbol(symbol, &owner, &crc, 1);
1233 if (value && !strong_try_module_get(owner))
1234 value = 0;
1235 preempt_enable();
1236
1237 return (void *)value;
1238 }
1239 EXPORT_SYMBOL_GPL(__symbol_get);
1240
1241 /*
1242 * Ensure that an exported symbol [global namespace] does not already exist
1243 * in the kernel or in some other module's exported symbol table.
1244 */
1245 static int verify_export_symbols(struct module *mod)
1246 {
1247 const char *name = NULL;
1248 unsigned long i, ret = 0;
1249 struct module *owner;
1250 const unsigned long *crc;
1251
1252 for (i = 0; i < mod->num_syms; i++)
1253 if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) {
1254 name = mod->syms[i].name;
1255 ret = -ENOEXEC;
1256 goto dup;
1257 }
1258
1259 for (i = 0; i < mod->num_gpl_syms; i++)
1260 if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) {
1261 name = mod->gpl_syms[i].name;
1262 ret = -ENOEXEC;
1263 goto dup;
1264 }
1265
1266 dup:
1267 if (ret)
1268 printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
1269 mod->name, name, module_name(owner));
1270
1271 return ret;
1272 }
1273
1274 /* Change all symbols so that sh_value encodes the pointer directly. */
1275 static int simplify_symbols(Elf_Shdr *sechdrs,
1276 unsigned int symindex,
1277 const char *strtab,
1278 unsigned int versindex,
1279 unsigned int pcpuindex,
1280 struct module *mod)
1281 {
1282 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1283 unsigned long secbase;
1284 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1285 int ret = 0;
1286
1287 for (i = 1; i < n; i++) {
1288 switch (sym[i].st_shndx) {
1289 case SHN_COMMON:
1290 /* We compiled with -fno-common. These are not
1291 supposed to happen. */
1292 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1293 printk("%s: please compile with -fno-common\n",
1294 mod->name);
1295 ret = -ENOEXEC;
1296 break;
1297
1298 case SHN_ABS:
1299 /* Don't need to do anything */
1300 DEBUGP("Absolute symbol: 0x%08lx\n",
1301 (long)sym[i].st_value);
1302 break;
1303
1304 case SHN_UNDEF:
1305 sym[i].st_value
1306 = resolve_symbol(sechdrs, versindex,
1307 strtab + sym[i].st_name, mod);
1308
1309 /* Ok if resolved. */
1310 if (sym[i].st_value != 0)
1311 break;
1312 /* Ok if weak. */
1313 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1314 break;
1315
1316 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1317 mod->name, strtab + sym[i].st_name);
1318 ret = -ENOENT;
1319 break;
1320
1321 default:
1322 /* Divert to percpu allocation if a percpu var. */
1323 if (sym[i].st_shndx == pcpuindex)
1324 secbase = (unsigned long)mod->percpu;
1325 else
1326 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1327 sym[i].st_value += secbase;
1328 break;
1329 }
1330 }
1331
1332 return ret;
1333 }
1334
1335 /* Update size with this section: return offset. */
1336 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
1337 {
1338 long ret;
1339
1340 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1341 *size = ret + sechdr->sh_size;
1342 return ret;
1343 }
1344
1345 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1346 might -- code, read-only data, read-write data, small data. Tally
1347 sizes, and place the offsets into sh_entsize fields: high bit means it
1348 belongs in init. */
1349 static void layout_sections(struct module *mod,
1350 const Elf_Ehdr *hdr,
1351 Elf_Shdr *sechdrs,
1352 const char *secstrings)
1353 {
1354 static unsigned long const masks[][2] = {
1355 /* NOTE: all executable code must be the first section
1356 * in this array; otherwise modify the text_size
1357 * finder in the two loops below */
1358 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1359 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1360 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1361 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1362 };
1363 unsigned int m, i;
1364
1365 for (i = 0; i < hdr->e_shnum; i++)
1366 sechdrs[i].sh_entsize = ~0UL;
1367
1368 DEBUGP("Core section allocation order:\n");
1369 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1370 for (i = 0; i < hdr->e_shnum; ++i) {
1371 Elf_Shdr *s = &sechdrs[i];
1372
1373 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1374 || (s->sh_flags & masks[m][1])
1375 || s->sh_entsize != ~0UL
1376 || strncmp(secstrings + s->sh_name,
1377 ".init", 5) == 0)
1378 continue;
1379 s->sh_entsize = get_offset(&mod->core_size, s);
1380 DEBUGP("\t%s\n", secstrings + s->sh_name);
1381 }
1382 if (m == 0)
1383 mod->core_text_size = mod->core_size;
1384 }
1385
1386 DEBUGP("Init section allocation order:\n");
1387 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1388 for (i = 0; i < hdr->e_shnum; ++i) {
1389 Elf_Shdr *s = &sechdrs[i];
1390
1391 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1392 || (s->sh_flags & masks[m][1])
1393 || s->sh_entsize != ~0UL
1394 || strncmp(secstrings + s->sh_name,
1395 ".init", 5) != 0)
1396 continue;
1397 s->sh_entsize = (get_offset(&mod->init_size, s)
1398 | INIT_OFFSET_MASK);
1399 DEBUGP("\t%s\n", secstrings + s->sh_name);
1400 }
1401 if (m == 0)
1402 mod->init_text_size = mod->init_size;
1403 }
1404 }
1405
1406 static void set_license(struct module *mod, const char *license)
1407 {
1408 if (!license)
1409 license = "unspecified";
1410
1411 if (!license_is_gpl_compatible(license)) {
1412 if (!(tainted & TAINT_PROPRIETARY_MODULE))
1413 printk(KERN_WARNING "%s: module license '%s' taints "
1414 "kernel.\n", mod->name, license);
1415 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1416 }
1417 }
1418
1419 /* Parse tag=value strings from .modinfo section */
1420 static char *next_string(char *string, unsigned long *secsize)
1421 {
1422 /* Skip non-zero chars */
1423 while (string[0]) {
1424 string++;
1425 if ((*secsize)-- <= 1)
1426 return NULL;
1427 }
1428
1429 /* Skip any zero padding. */
1430 while (!string[0]) {
1431 string++;
1432 if ((*secsize)-- <= 1)
1433 return NULL;
1434 }
1435 return string;
1436 }
1437
1438 static char *get_modinfo(Elf_Shdr *sechdrs,
1439 unsigned int info,
1440 const char *tag)
1441 {
1442 char *p;
1443 unsigned int taglen = strlen(tag);
1444 unsigned long size = sechdrs[info].sh_size;
1445
1446 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1447 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1448 return p + taglen + 1;
1449 }
1450 return NULL;
1451 }
1452
1453 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1454 unsigned int infoindex)
1455 {
1456 struct module_attribute *attr;
1457 int i;
1458
1459 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1460 if (attr->setup)
1461 attr->setup(mod,
1462 get_modinfo(sechdrs,
1463 infoindex,
1464 attr->attr.name));
1465 }
1466 }
1467
1468 #ifdef CONFIG_KALLSYMS
1469 static int is_exported(const char *name, const struct module *mod)
1470 {
1471 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1472 return 1;
1473 else
1474 if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1475 return 1;
1476 else
1477 return 0;
1478 }
1479
1480 /* As per nm */
1481 static char elf_type(const Elf_Sym *sym,
1482 Elf_Shdr *sechdrs,
1483 const char *secstrings,
1484 struct module *mod)
1485 {
1486 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1487 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1488 return 'v';
1489 else
1490 return 'w';
1491 }
1492 if (sym->st_shndx == SHN_UNDEF)
1493 return 'U';
1494 if (sym->st_shndx == SHN_ABS)
1495 return 'a';
1496 if (sym->st_shndx >= SHN_LORESERVE)
1497 return '?';
1498 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1499 return 't';
1500 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1501 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1502 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1503 return 'r';
1504 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1505 return 'g';
1506 else
1507 return 'd';
1508 }
1509 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1510 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1511 return 's';
1512 else
1513 return 'b';
1514 }
1515 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1516 ".debug", strlen(".debug")) == 0)
1517 return 'n';
1518 return '?';
1519 }
1520
1521 static void add_kallsyms(struct module *mod,
1522 Elf_Shdr *sechdrs,
1523 unsigned int symindex,
1524 unsigned int strindex,
1525 const char *secstrings)
1526 {
1527 unsigned int i;
1528
1529 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1530 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1531 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1532
1533 /* Set types up while we still have access to sections. */
1534 for (i = 0; i < mod->num_symtab; i++)
1535 mod->symtab[i].st_info
1536 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1537 }
1538 #else
1539 static inline void add_kallsyms(struct module *mod,
1540 Elf_Shdr *sechdrs,
1541 unsigned int symindex,
1542 unsigned int strindex,
1543 const char *secstrings)
1544 {
1545 }
1546 #endif /* CONFIG_KALLSYMS */
1547
1548 /* Allocate and load the module: note that size of section 0 is always
1549 zero, and we rely on this for optional sections. */
1550 static struct module *load_module(void __user *umod,
1551 unsigned long len,
1552 const char __user *uargs)
1553 {
1554 Elf_Ehdr *hdr;
1555 Elf_Shdr *sechdrs;
1556 char *secstrings, *args, *modmagic, *strtab = NULL;
1557 unsigned int i;
1558 unsigned int symindex = 0;
1559 unsigned int strindex = 0;
1560 unsigned int setupindex;
1561 unsigned int exindex;
1562 unsigned int exportindex;
1563 unsigned int modindex;
1564 unsigned int obsparmindex;
1565 unsigned int infoindex;
1566 unsigned int gplindex;
1567 unsigned int crcindex;
1568 unsigned int gplcrcindex;
1569 unsigned int versindex;
1570 unsigned int pcpuindex;
1571 unsigned int gplfutureindex;
1572 unsigned int gplfuturecrcindex;
1573 unsigned int unwindex = 0;
1574 unsigned int unusedindex;
1575 unsigned int unusedcrcindex;
1576 unsigned int unusedgplindex;
1577 unsigned int unusedgplcrcindex;
1578 struct module *mod;
1579 long err = 0;
1580 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1581 struct exception_table_entry *extable;
1582 mm_segment_t old_fs;
1583
1584 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1585 umod, len, uargs);
1586 if (len < sizeof(*hdr))
1587 return ERR_PTR(-ENOEXEC);
1588
1589 /* Suck in entire file: we'll want most of it. */
1590 /* vmalloc barfs on "unusual" numbers. Check here */
1591 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1592 return ERR_PTR(-ENOMEM);
1593 if (copy_from_user(hdr, umod, len) != 0) {
1594 err = -EFAULT;
1595 goto free_hdr;
1596 }
1597
1598 /* Sanity checks against insmoding binaries or wrong arch,
1599 weird elf version */
1600 if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
1601 || hdr->e_type != ET_REL
1602 || !elf_check_arch(hdr)
1603 || hdr->e_shentsize != sizeof(*sechdrs)) {
1604 err = -ENOEXEC;
1605 goto free_hdr;
1606 }
1607
1608 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1609 goto truncated;
1610
1611 /* Convenience variables */
1612 sechdrs = (void *)hdr + hdr->e_shoff;
1613 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1614 sechdrs[0].sh_addr = 0;
1615
1616 for (i = 1; i < hdr->e_shnum; i++) {
1617 if (sechdrs[i].sh_type != SHT_NOBITS
1618 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1619 goto truncated;
1620
1621 /* Mark all sections sh_addr with their address in the
1622 temporary image. */
1623 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1624
1625 /* Internal symbols and strings. */
1626 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1627 symindex = i;
1628 strindex = sechdrs[i].sh_link;
1629 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1630 }
1631 #ifndef CONFIG_MODULE_UNLOAD
1632 /* Don't load .exit sections */
1633 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1634 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1635 #endif
1636 }
1637
1638 modindex = find_sec(hdr, sechdrs, secstrings,
1639 ".gnu.linkonce.this_module");
1640 if (!modindex) {
1641 printk(KERN_WARNING "No module found in object\n");
1642 err = -ENOEXEC;
1643 goto free_hdr;
1644 }
1645 mod = (void *)sechdrs[modindex].sh_addr;
1646
1647 if (symindex == 0) {
1648 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1649 mod->name);
1650 err = -ENOEXEC;
1651 goto free_hdr;
1652 }
1653
1654 /* Optional sections */
1655 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1656 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1657 gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1658 unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
1659 unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
1660 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1661 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1662 gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1663 unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
1664 unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
1665 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1666 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1667 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1668 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1669 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1670 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1671 #ifdef ARCH_UNWIND_SECTION_NAME
1672 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1673 #endif
1674
1675 /* Don't keep modinfo section */
1676 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1677 #ifdef CONFIG_KALLSYMS
1678 /* Keep symbol and string tables for decoding later. */
1679 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1680 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1681 #endif
1682 if (unwindex)
1683 sechdrs[unwindex].sh_flags |= SHF_ALLOC;
1684
1685 /* Check module struct version now, before we try to use module. */
1686 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1687 err = -ENOEXEC;
1688 goto free_hdr;
1689 }
1690
1691 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1692 /* This is allowed: modprobe --force will invalidate it. */
1693 if (!modmagic) {
1694 add_taint_module(mod, TAINT_FORCED_MODULE);
1695 printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
1696 mod->name);
1697 } else if (!same_magic(modmagic, vermagic)) {
1698 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1699 mod->name, modmagic, vermagic);
1700 err = -ENOEXEC;
1701 goto free_hdr;
1702 }
1703
1704 /* Now copy in args */
1705 args = strndup_user(uargs, ~0UL >> 1);
1706 if (IS_ERR(args)) {
1707 err = PTR_ERR(args);
1708 goto free_hdr;
1709 }
1710
1711 if (find_module(mod->name)) {
1712 err = -EEXIST;
1713 goto free_mod;
1714 }
1715
1716 mod->state = MODULE_STATE_COMING;
1717
1718 /* Allow arches to frob section contents and sizes. */
1719 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1720 if (err < 0)
1721 goto free_mod;
1722
1723 if (pcpuindex) {
1724 /* We have a special allocation for this section. */
1725 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1726 sechdrs[pcpuindex].sh_addralign,
1727 mod->name);
1728 if (!percpu) {
1729 err = -ENOMEM;
1730 goto free_mod;
1731 }
1732 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1733 mod->percpu = percpu;
1734 }
1735
1736 /* Determine total sizes, and put offsets in sh_entsize. For now
1737 this is done generically; there doesn't appear to be any
1738 special cases for the architectures. */
1739 layout_sections(mod, hdr, sechdrs, secstrings);
1740
1741 /* Do the allocs. */
1742 ptr = module_alloc(mod->core_size);
1743 if (!ptr) {
1744 err = -ENOMEM;
1745 goto free_percpu;
1746 }
1747 memset(ptr, 0, mod->core_size);
1748 mod->module_core = ptr;
1749
1750 ptr = module_alloc(mod->init_size);
1751 if (!ptr && mod->init_size) {
1752 err = -ENOMEM;
1753 goto free_core;
1754 }
1755 memset(ptr, 0, mod->init_size);
1756 mod->module_init = ptr;
1757
1758 /* Transfer each section which specifies SHF_ALLOC */
1759 DEBUGP("final section addresses:\n");
1760 for (i = 0; i < hdr->e_shnum; i++) {
1761 void *dest;
1762
1763 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1764 continue;
1765
1766 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
1767 dest = mod->module_init
1768 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
1769 else
1770 dest = mod->module_core + sechdrs[i].sh_entsize;
1771
1772 if (sechdrs[i].sh_type != SHT_NOBITS)
1773 memcpy(dest, (void *)sechdrs[i].sh_addr,
1774 sechdrs[i].sh_size);
1775 /* Update sh_addr to point to copy in image. */
1776 sechdrs[i].sh_addr = (unsigned long)dest;
1777 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
1778 }
1779 /* Module has been moved. */
1780 mod = (void *)sechdrs[modindex].sh_addr;
1781
1782 /* Now we've moved module, initialize linked lists, etc. */
1783 module_unload_init(mod);
1784
1785 /* Initialize kobject, so we can reference it. */
1786 if (mod_sysfs_init(mod) != 0)
1787 goto cleanup;
1788
1789 /* Set up license info based on the info section */
1790 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
1791
1792 if (strcmp(mod->name, "ndiswrapper") == 0)
1793 add_taint(TAINT_PROPRIETARY_MODULE);
1794 if (strcmp(mod->name, "driverloader") == 0)
1795 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1796
1797 /* Set up MODINFO_ATTR fields */
1798 setup_modinfo(mod, sechdrs, infoindex);
1799
1800 /* Fix up syms, so that st_value is a pointer to location. */
1801 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
1802 mod);
1803 if (err < 0)
1804 goto cleanup;
1805
1806 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
1807 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
1808 mod->syms = (void *)sechdrs[exportindex].sh_addr;
1809 if (crcindex)
1810 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
1811 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
1812 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
1813 if (gplcrcindex)
1814 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
1815 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
1816 sizeof(*mod->gpl_future_syms);
1817 mod->num_unused_syms = sechdrs[unusedindex].sh_size /
1818 sizeof(*mod->unused_syms);
1819 mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
1820 sizeof(*mod->unused_gpl_syms);
1821 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
1822 if (gplfuturecrcindex)
1823 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
1824
1825 mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
1826 if (unusedcrcindex)
1827 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
1828 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
1829 if (unusedgplcrcindex)
1830 mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr;
1831
1832 #ifdef CONFIG_MODVERSIONS
1833 if ((mod->num_syms && !crcindex) ||
1834 (mod->num_gpl_syms && !gplcrcindex) ||
1835 (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
1836 (mod->num_unused_syms && !unusedcrcindex) ||
1837 (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
1838 printk(KERN_WARNING "%s: No versions for exported symbols."
1839 " Tainting kernel.\n", mod->name);
1840 add_taint_module(mod, TAINT_FORCED_MODULE);
1841 }
1842 #endif
1843
1844 /* Now do relocations. */
1845 for (i = 1; i < hdr->e_shnum; i++) {
1846 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1847 unsigned int info = sechdrs[i].sh_info;
1848
1849 /* Not a valid relocation section? */
1850 if (info >= hdr->e_shnum)
1851 continue;
1852
1853 /* Don't bother with non-allocated sections */
1854 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1855 continue;
1856
1857 if (sechdrs[i].sh_type == SHT_REL)
1858 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
1859 else if (sechdrs[i].sh_type == SHT_RELA)
1860 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1861 mod);
1862 if (err < 0)
1863 goto cleanup;
1864 }
1865
1866 /* Find duplicate symbols */
1867 err = verify_export_symbols(mod);
1868
1869 if (err < 0)
1870 goto cleanup;
1871
1872 /* Set up and sort exception table */
1873 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
1874 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
1875 sort_extable(extable, extable + mod->num_exentries);
1876
1877 /* Finally, copy percpu area over. */
1878 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
1879 sechdrs[pcpuindex].sh_size);
1880
1881 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
1882
1883 err = module_finalize(hdr, sechdrs, mod);
1884 if (err < 0)
1885 goto cleanup;
1886
1887 /* flush the icache in correct context */
1888 old_fs = get_fs();
1889 set_fs(KERNEL_DS);
1890
1891 /*
1892 * Flush the instruction cache, since we've played with text.
1893 * Do it before processing of module parameters, so the module
1894 * can provide parameter accessor functions of its own.
1895 */
1896 if (mod->module_init)
1897 flush_icache_range((unsigned long)mod->module_init,
1898 (unsigned long)mod->module_init
1899 + mod->init_size);
1900 flush_icache_range((unsigned long)mod->module_core,
1901 (unsigned long)mod->module_core + mod->core_size);
1902
1903 set_fs(old_fs);
1904
1905 mod->args = args;
1906 if (obsparmindex)
1907 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
1908 mod->name);
1909
1910 /* Size of section 0 is 0, so this works well if no params */
1911 err = parse_args(mod->name, mod->args,
1912 (struct kernel_param *)
1913 sechdrs[setupindex].sh_addr,
1914 sechdrs[setupindex].sh_size
1915 / sizeof(struct kernel_param),
1916 NULL);
1917 if (err < 0)
1918 goto arch_cleanup;
1919
1920 err = mod_sysfs_setup(mod,
1921 (struct kernel_param *)
1922 sechdrs[setupindex].sh_addr,
1923 sechdrs[setupindex].sh_size
1924 / sizeof(struct kernel_param));
1925 if (err < 0)
1926 goto arch_cleanup;
1927 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
1928
1929 /* Size of section 0 is 0, so this works well if no unwind info. */
1930 mod->unwind_info = unwind_add_table(mod,
1931 (void *)sechdrs[unwindex].sh_addr,
1932 sechdrs[unwindex].sh_size);
1933
1934 /* Get rid of temporary copy */
1935 vfree(hdr);
1936
1937 /* Done! */
1938 return mod;
1939
1940 arch_cleanup:
1941 module_arch_cleanup(mod);
1942 cleanup:
1943 module_unload_free(mod);
1944 module_free(mod, mod->module_init);
1945 free_core:
1946 module_free(mod, mod->module_core);
1947 free_percpu:
1948 if (percpu)
1949 percpu_modfree(percpu);
1950 free_mod:
1951 kfree(args);
1952 free_hdr:
1953 vfree(hdr);
1954 return ERR_PTR(err);
1955
1956 truncated:
1957 printk(KERN_ERR "Module len %lu truncated\n", len);
1958 err = -ENOEXEC;
1959 goto free_hdr;
1960 }
1961
1962 /*
1963 * link the module with the whole machine is stopped with interrupts off
1964 * - this defends against kallsyms not taking locks
1965 */
1966 static int __link_module(void *_mod)
1967 {
1968 struct module *mod = _mod;
1969 list_add(&mod->list, &modules);
1970 return 0;
1971 }
1972
1973 /* This is where the real work happens */
1974 asmlinkage long
1975 sys_init_module(void __user *umod,
1976 unsigned long len,
1977 const char __user *uargs)
1978 {
1979 struct module *mod;
1980 int ret = 0;
1981
1982 /* Must have permission */
1983 if (!capable(CAP_SYS_MODULE))
1984 return -EPERM;
1985
1986 /* Only one module load at a time, please */
1987 if (mutex_lock_interruptible(&module_mutex) != 0)
1988 return -EINTR;
1989
1990 /* Do all the hard work */
1991 mod = load_module(umod, len, uargs);
1992 if (IS_ERR(mod)) {
1993 mutex_unlock(&module_mutex);
1994 return PTR_ERR(mod);
1995 }
1996
1997 /* Now sew it into the lists. They won't access us, since
1998 strong_try_module_get() will fail. */
1999 stop_machine_run(__link_module, mod, NR_CPUS);
2000
2001 /* Drop lock so they can recurse */
2002 mutex_unlock(&module_mutex);
2003
2004 blocking_notifier_call_chain(&module_notify_list,
2005 MODULE_STATE_COMING, mod);
2006
2007 /* Start the module */
2008 if (mod->init != NULL)
2009 ret = mod->init();
2010 if (ret < 0) {
2011 /* Init routine failed: abort. Try to protect us from
2012 buggy refcounters. */
2013 mod->state = MODULE_STATE_GOING;
2014 synchronize_sched();
2015 if (mod->unsafe)
2016 printk(KERN_ERR "%s: module is now stuck!\n",
2017 mod->name);
2018 else {
2019 module_put(mod);
2020 mutex_lock(&module_mutex);
2021 free_module(mod);
2022 mutex_unlock(&module_mutex);
2023 }
2024 return ret;
2025 }
2026
2027 /* Now it's a first class citizen! */
2028 mutex_lock(&module_mutex);
2029 mod->state = MODULE_STATE_LIVE;
2030 /* Drop initial reference. */
2031 module_put(mod);
2032 unwind_remove_table(mod->unwind_info, 1);
2033 module_free(mod, mod->module_init);
2034 mod->module_init = NULL;
2035 mod->init_size = 0;
2036 mod->init_text_size = 0;
2037 mutex_unlock(&module_mutex);
2038
2039 return 0;
2040 }
2041
2042 static inline int within(unsigned long addr, void *start, unsigned long size)
2043 {
2044 return ((void *)addr >= start && (void *)addr < start + size);
2045 }
2046
2047 #ifdef CONFIG_KALLSYMS
2048 /*
2049 * This ignores the intensely annoying "mapping symbols" found
2050 * in ARM ELF files: $a, $t and $d.
2051 */
2052 static inline int is_arm_mapping_symbol(const char *str)
2053 {
2054 return str[0] == '$' && strchr("atd", str[1])
2055 && (str[2] == '\0' || str[2] == '.');
2056 }
2057
2058 static const char *get_ksymbol(struct module *mod,
2059 unsigned long addr,
2060 unsigned long *size,
2061 unsigned long *offset)
2062 {
2063 unsigned int i, best = 0;
2064 unsigned long nextval;
2065
2066 /* At worse, next value is at end of module */
2067 if (within(addr, mod->module_init, mod->init_size))
2068 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2069 else
2070 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2071
2072 /* Scan for closest preceeding symbol, and next symbol. (ELF
2073 starts real symbols at 1). */
2074 for (i = 1; i < mod->num_symtab; i++) {
2075 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2076 continue;
2077
2078 /* We ignore unnamed symbols: they're uninformative
2079 * and inserted at a whim. */
2080 if (mod->symtab[i].st_value <= addr
2081 && mod->symtab[i].st_value > mod->symtab[best].st_value
2082 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2083 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2084 best = i;
2085 if (mod->symtab[i].st_value > addr
2086 && mod->symtab[i].st_value < nextval
2087 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2088 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2089 nextval = mod->symtab[i].st_value;
2090 }
2091
2092 if (!best)
2093 return NULL;
2094
2095 if (size)
2096 *size = nextval - mod->symtab[best].st_value;
2097 if (offset)
2098 *offset = addr - mod->symtab[best].st_value;
2099 return mod->strtab + mod->symtab[best].st_name;
2100 }
2101
2102 /* For kallsyms to ask for address resolution. NULL means not found.
2103 We don't lock, as this is used for oops resolution and races are a
2104 lesser concern. */
2105 const char *module_address_lookup(unsigned long addr,
2106 unsigned long *size,
2107 unsigned long *offset,
2108 char **modname)
2109 {
2110 struct module *mod;
2111
2112 list_for_each_entry(mod, &modules, list) {
2113 if (within(addr, mod->module_init, mod->init_size)
2114 || within(addr, mod->module_core, mod->core_size)) {
2115 if (modname)
2116 *modname = mod->name;
2117 return get_ksymbol(mod, addr, size, offset);
2118 }
2119 }
2120 return NULL;
2121 }
2122
2123 int lookup_module_symbol_name(unsigned long addr, char *symname)
2124 {
2125 struct module *mod;
2126
2127 mutex_lock(&module_mutex);
2128 list_for_each_entry(mod, &modules, list) {
2129 if (within(addr, mod->module_init, mod->init_size) ||
2130 within(addr, mod->module_core, mod->core_size)) {
2131 const char *sym;
2132
2133 sym = get_ksymbol(mod, addr, NULL, NULL);
2134 if (!sym)
2135 goto out;
2136 strlcpy(symname, sym, KSYM_NAME_LEN);
2137 mutex_unlock(&module_mutex);
2138 return 0;
2139 }
2140 }
2141 out:
2142 mutex_unlock(&module_mutex);
2143 return -ERANGE;
2144 }
2145
2146 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2147 unsigned long *offset, char *modname, char *name)
2148 {
2149 struct module *mod;
2150
2151 mutex_lock(&module_mutex);
2152 list_for_each_entry(mod, &modules, list) {
2153 if (within(addr, mod->module_init, mod->init_size) ||
2154 within(addr, mod->module_core, mod->core_size)) {
2155 const char *sym;
2156
2157 sym = get_ksymbol(mod, addr, size, offset);
2158 if (!sym)
2159 goto out;
2160 if (modname)
2161 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2162 if (name)
2163 strlcpy(name, sym, KSYM_NAME_LEN);
2164 mutex_unlock(&module_mutex);
2165 return 0;
2166 }
2167 }
2168 out:
2169 mutex_unlock(&module_mutex);
2170 return -ERANGE;
2171 }
2172
2173 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2174 char *name, char *module_name, int *exported)
2175 {
2176 struct module *mod;
2177
2178 mutex_lock(&module_mutex);
2179 list_for_each_entry(mod, &modules, list) {
2180 if (symnum < mod->num_symtab) {
2181 *value = mod->symtab[symnum].st_value;
2182 *type = mod->symtab[symnum].st_info;
2183 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2184 KSYM_NAME_LEN);
2185 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2186 *exported = is_exported(name, mod);
2187 mutex_unlock(&module_mutex);
2188 return 0;
2189 }
2190 symnum -= mod->num_symtab;
2191 }
2192 mutex_unlock(&module_mutex);
2193 return -ERANGE;
2194 }
2195
2196 static unsigned long mod_find_symname(struct module *mod, const char *name)
2197 {
2198 unsigned int i;
2199
2200 for (i = 0; i < mod->num_symtab; i++)
2201 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2202 mod->symtab[i].st_info != 'U')
2203 return mod->symtab[i].st_value;
2204 return 0;
2205 }
2206
2207 /* Look for this name: can be of form module:name. */
2208 unsigned long module_kallsyms_lookup_name(const char *name)
2209 {
2210 struct module *mod;
2211 char *colon;
2212 unsigned long ret = 0;
2213
2214 /* Don't lock: we're in enough trouble already. */
2215 if ((colon = strchr(name, ':')) != NULL) {
2216 *colon = '\0';
2217 if ((mod = find_module(name)) != NULL)
2218 ret = mod_find_symname(mod, colon+1);
2219 *colon = ':';
2220 } else {
2221 list_for_each_entry(mod, &modules, list)
2222 if ((ret = mod_find_symname(mod, name)) != 0)
2223 break;
2224 }
2225 return ret;
2226 }
2227 #endif /* CONFIG_KALLSYMS */
2228
2229 /* Called by the /proc file system to return a list of modules. */
2230 static void *m_start(struct seq_file *m, loff_t *pos)
2231 {
2232 mutex_lock(&module_mutex);
2233 return seq_list_start(&modules, *pos);
2234 }
2235
2236 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2237 {
2238 return seq_list_next(p, &modules, pos);
2239 }
2240
2241 static void m_stop(struct seq_file *m, void *p)
2242 {
2243 mutex_unlock(&module_mutex);
2244 }
2245
2246 static char *taint_flags(unsigned int taints, char *buf)
2247 {
2248 int bx = 0;
2249
2250 if (taints) {
2251 buf[bx++] = '(';
2252 if (taints & TAINT_PROPRIETARY_MODULE)
2253 buf[bx++] = 'P';
2254 if (taints & TAINT_FORCED_MODULE)
2255 buf[bx++] = 'F';
2256 /*
2257 * TAINT_FORCED_RMMOD: could be added.
2258 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2259 * apply to modules.
2260 */
2261 buf[bx++] = ')';
2262 }
2263 buf[bx] = '\0';
2264
2265 return buf;
2266 }
2267
2268 static int m_show(struct seq_file *m, void *p)
2269 {
2270 struct module *mod = list_entry(p, struct module, list);
2271 char buf[8];
2272
2273 seq_printf(m, "%s %lu",
2274 mod->name, mod->init_size + mod->core_size);
2275 print_unload_info(m, mod);
2276
2277 /* Informative for users. */
2278 seq_printf(m, " %s",
2279 mod->state == MODULE_STATE_GOING ? "Unloading":
2280 mod->state == MODULE_STATE_COMING ? "Loading":
2281 "Live");
2282 /* Used by oprofile and other similar tools. */
2283 seq_printf(m, " 0x%p", mod->module_core);
2284
2285 /* Taints info */
2286 if (mod->taints)
2287 seq_printf(m, " %s", taint_flags(mod->taints, buf));
2288
2289 seq_printf(m, "\n");
2290 return 0;
2291 }
2292
2293 /* Format: modulename size refcount deps address
2294
2295 Where refcount is a number or -, and deps is a comma-separated list
2296 of depends or -.
2297 */
2298 const struct seq_operations modules_op = {
2299 .start = m_start,
2300 .next = m_next,
2301 .stop = m_stop,
2302 .show = m_show
2303 };
2304
2305 /* Given an address, look for it in the module exception tables. */
2306 const struct exception_table_entry *search_module_extables(unsigned long addr)
2307 {
2308 const struct exception_table_entry *e = NULL;
2309 struct module *mod;
2310
2311 preempt_disable();
2312 list_for_each_entry(mod, &modules, list) {
2313 if (mod->num_exentries == 0)
2314 continue;
2315
2316 e = search_extable(mod->extable,
2317 mod->extable + mod->num_exentries - 1,
2318 addr);
2319 if (e)
2320 break;
2321 }
2322 preempt_enable();
2323
2324 /* Now, if we found one, we are running inside it now, hence
2325 we cannot unload the module, hence no refcnt needed. */
2326 return e;
2327 }
2328
2329 /*
2330 * Is this a valid module address?
2331 */
2332 int is_module_address(unsigned long addr)
2333 {
2334 struct module *mod;
2335
2336 preempt_disable();
2337
2338 list_for_each_entry(mod, &modules, list) {
2339 if (within(addr, mod->module_core, mod->core_size)) {
2340 preempt_enable();
2341 return 1;
2342 }
2343 }
2344
2345 preempt_enable();
2346
2347 return 0;
2348 }
2349
2350
2351 /* Is this a valid kernel address? */
2352 struct module *__module_text_address(unsigned long addr)
2353 {
2354 struct module *mod;
2355
2356 list_for_each_entry(mod, &modules, list)
2357 if (within(addr, mod->module_init, mod->init_text_size)
2358 || within(addr, mod->module_core, mod->core_text_size))
2359 return mod;
2360 return NULL;
2361 }
2362
2363 struct module *module_text_address(unsigned long addr)
2364 {
2365 struct module *mod;
2366
2367 preempt_disable();
2368 mod = __module_text_address(addr);
2369 preempt_enable();
2370
2371 return mod;
2372 }
2373
2374 /* Don't grab lock, we're oopsing. */
2375 void print_modules(void)
2376 {
2377 struct module *mod;
2378 char buf[8];
2379
2380 printk("Modules linked in:");
2381 list_for_each_entry(mod, &modules, list)
2382 printk(" %s%s", mod->name, taint_flags(mod->taints, buf));
2383 printk("\n");
2384 }
2385
2386 #ifdef CONFIG_SYSFS
2387 static char *make_driver_name(struct device_driver *drv)
2388 {
2389 char *driver_name;
2390
2391 driver_name = kmalloc(strlen(drv->name) + strlen(drv->bus->name) + 2,
2392 GFP_KERNEL);
2393 if (!driver_name)
2394 return NULL;
2395
2396 sprintf(driver_name, "%s:%s", drv->bus->name, drv->name);
2397 return driver_name;
2398 }
2399
2400 static void module_create_drivers_dir(struct module_kobject *mk)
2401 {
2402 if (!mk || mk->drivers_dir)
2403 return;
2404
2405 mk->drivers_dir = kobject_add_dir(&mk->kobj, "drivers");
2406 }
2407
2408 void module_add_driver(struct module *mod, struct device_driver *drv)
2409 {
2410 char *driver_name;
2411 int no_warn;
2412 struct module_kobject *mk = NULL;
2413
2414 if (!drv)
2415 return;
2416
2417 if (mod)
2418 mk = &mod->mkobj;
2419 else if (drv->mod_name) {
2420 struct kobject *mkobj;
2421
2422 /* Lookup built-in module entry in /sys/modules */
2423 mkobj = kset_find_obj(&module_subsys, drv->mod_name);
2424 if (mkobj) {
2425 mk = container_of(mkobj, struct module_kobject, kobj);
2426 /* remember our module structure */
2427 drv->mkobj = mk;
2428 /* kset_find_obj took a reference */
2429 kobject_put(mkobj);
2430 }
2431 }
2432
2433 if (!mk)
2434 return;
2435
2436 /* Don't check return codes; these calls are idempotent */
2437 no_warn = sysfs_create_link(&drv->kobj, &mk->kobj, "module");
2438 driver_name = make_driver_name(drv);
2439 if (driver_name) {
2440 module_create_drivers_dir(mk);
2441 no_warn = sysfs_create_link(mk->drivers_dir, &drv->kobj,
2442 driver_name);
2443 kfree(driver_name);
2444 }
2445 }
2446 EXPORT_SYMBOL(module_add_driver);
2447
2448 void module_remove_driver(struct device_driver *drv)
2449 {
2450 struct module_kobject *mk = NULL;
2451 char *driver_name;
2452
2453 if (!drv)
2454 return;
2455
2456 sysfs_remove_link(&drv->kobj, "module");
2457
2458 if (drv->owner)
2459 mk = &drv->owner->mkobj;
2460 else if (drv->mkobj)
2461 mk = drv->mkobj;
2462 if (mk && mk->drivers_dir) {
2463 driver_name = make_driver_name(drv);
2464 if (driver_name) {
2465 sysfs_remove_link(mk->drivers_dir, driver_name);
2466 kfree(driver_name);
2467 }
2468 }
2469 }
2470 EXPORT_SYMBOL(module_remove_driver);
2471 #endif
2472
2473 #ifdef CONFIG_MODVERSIONS
2474 /* Generate the signature for struct module here, too, for modversions. */
2475 void struct_module(struct module *mod) { return; }
2476 EXPORT_SYMBOL(struct_module);
2477 #endif
Stable & featurefull patchset based on Linus's git branch