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