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[NET_SCHED]: Fix endless loops (part 4): HTB
[hh.org.git] / kernel / module.c
blob45e01cb60101128c26737907c6c23d2a8acb58ab
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/stop_machine.h>
38 #include <linux/device.h>
39 #include <linux/string.h>
40 #include <linux/sched.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 #else /* !CONFIG_MODULE_UNLOAD */
794 static void print_unload_info(struct seq_file *m, struct module *mod)
795 {
796 /* We don't know the usage count, or what modules are using. */
797 seq_printf(m, " - -");
798 }
799
800 static inline void module_unload_free(struct module *mod)
801 {
802 }
803
804 static inline int use_module(struct module *a, struct module *b)
805 {
806 return strong_try_module_get(b);
807 }
808
809 static inline void module_unload_init(struct module *mod)
810 {
811 }
812 #endif /* CONFIG_MODULE_UNLOAD */
813
814 static struct module_attribute *modinfo_attrs[] = {
815 &modinfo_version,
816 &modinfo_srcversion,
817 #ifdef CONFIG_MODULE_UNLOAD
818 &refcnt,
819 #endif
820 NULL,
821 };
822
823 static const char vermagic[] = VERMAGIC_STRING;
824
825 #ifdef CONFIG_MODVERSIONS
826 static int check_version(Elf_Shdr *sechdrs,
827 unsigned int versindex,
828 const char *symname,
829 struct module *mod,
830 const unsigned long *crc)
831 {
832 unsigned int i, num_versions;
833 struct modversion_info *versions;
834
835 /* Exporting module didn't supply crcs? OK, we're already tainted. */
836 if (!crc)
837 return 1;
838
839 versions = (void *) sechdrs[versindex].sh_addr;
840 num_versions = sechdrs[versindex].sh_size
841 / sizeof(struct modversion_info);
842
843 for (i = 0; i < num_versions; i++) {
844 if (strcmp(versions[i].name, symname) != 0)
845 continue;
846
847 if (versions[i].crc == *crc)
848 return 1;
849 printk("%s: disagrees about version of symbol %s\n",
850 mod->name, symname);
851 DEBUGP("Found checksum %lX vs module %lX\n",
852 *crc, versions[i].crc);
853 return 0;
854 }
855 /* Not in module's version table. OK, but that taints the kernel. */
856 if (!(tainted & TAINT_FORCED_MODULE))
857 printk("%s: no version for \"%s\" found: kernel tainted.\n",
858 mod->name, symname);
859 add_taint_module(mod, TAINT_FORCED_MODULE);
860 return 1;
861 }
862
863 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
864 unsigned int versindex,
865 struct module *mod)
866 {
867 const unsigned long *crc;
868 struct module *owner;
869
870 if (!__find_symbol("struct_module", &owner, &crc, 1))
871 BUG();
872 return check_version(sechdrs, versindex, "struct_module", mod,
873 crc);
874 }
875
876 /* First part is kernel version, which we ignore. */
877 static inline int same_magic(const char *amagic, const char *bmagic)
878 {
879 amagic += strcspn(amagic, " ");
880 bmagic += strcspn(bmagic, " ");
881 return strcmp(amagic, bmagic) == 0;
882 }
883 #else
884 static inline int check_version(Elf_Shdr *sechdrs,
885 unsigned int versindex,
886 const char *symname,
887 struct module *mod,
888 const unsigned long *crc)
889 {
890 return 1;
891 }
892
893 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
894 unsigned int versindex,
895 struct module *mod)
896 {
897 return 1;
898 }
899
900 static inline int same_magic(const char *amagic, const char *bmagic)
901 {
902 return strcmp(amagic, bmagic) == 0;
903 }
904 #endif /* CONFIG_MODVERSIONS */
905
906 /* Resolve a symbol for this module. I.e. if we find one, record usage.
907 Must be holding module_mutex. */
908 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
909 unsigned int versindex,
910 const char *name,
911 struct module *mod)
912 {
913 struct module *owner;
914 unsigned long ret;
915 const unsigned long *crc;
916
917 ret = __find_symbol(name, &owner, &crc,
918 !(mod->taints & TAINT_PROPRIETARY_MODULE));
919 if (ret) {
920 /* use_module can fail due to OOM, or module unloading */
921 if (!check_version(sechdrs, versindex, name, mod, crc) ||
922 !use_module(mod, owner))
923 ret = 0;
924 }
925 return ret;
926 }
927
928
929 /*
930 * /sys/module/foo/sections stuff
931 * J. Corbet <corbet@lwn.net>
932 */
933 #ifdef CONFIG_KALLSYMS
934 static ssize_t module_sect_show(struct module_attribute *mattr,
935 struct module *mod, char *buf)
936 {
937 struct module_sect_attr *sattr =
938 container_of(mattr, struct module_sect_attr, mattr);
939 return sprintf(buf, "0x%lx\n", sattr->address);
940 }
941
942 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
943 {
944 int section;
945
946 for (section = 0; section < sect_attrs->nsections; section++)
947 kfree(sect_attrs->attrs[section].name);
948 kfree(sect_attrs);
949 }
950
951 static void add_sect_attrs(struct module *mod, unsigned int nsect,
952 char *secstrings, Elf_Shdr *sechdrs)
953 {
954 unsigned int nloaded = 0, i, size[2];
955 struct module_sect_attrs *sect_attrs;
956 struct module_sect_attr *sattr;
957 struct attribute **gattr;
958
959 /* Count loaded sections and allocate structures */
960 for (i = 0; i < nsect; i++)
961 if (sechdrs[i].sh_flags & SHF_ALLOC)
962 nloaded++;
963 size[0] = ALIGN(sizeof(*sect_attrs)
964 + nloaded * sizeof(sect_attrs->attrs[0]),
965 sizeof(sect_attrs->grp.attrs[0]));
966 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
967 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
968 if (sect_attrs == NULL)
969 return;
970
971 /* Setup section attributes. */
972 sect_attrs->grp.name = "sections";
973 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
974
975 sect_attrs->nsections = 0;
976 sattr = &sect_attrs->attrs[0];
977 gattr = &sect_attrs->grp.attrs[0];
978 for (i = 0; i < nsect; i++) {
979 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
980 continue;
981 sattr->address = sechdrs[i].sh_addr;
982 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
983 GFP_KERNEL);
984 if (sattr->name == NULL)
985 goto out;
986 sect_attrs->nsections++;
987 sattr->mattr.show = module_sect_show;
988 sattr->mattr.store = NULL;
989 sattr->mattr.attr.name = sattr->name;
990 sattr->mattr.attr.owner = mod;
991 sattr->mattr.attr.mode = S_IRUGO;
992 *(gattr++) = &(sattr++)->mattr.attr;
993 }
994 *gattr = NULL;
995
996 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
997 goto out;
998
999 mod->sect_attrs = sect_attrs;
1000 return;
1001 out:
1002 free_sect_attrs(sect_attrs);
1003 }
1004
1005 static void remove_sect_attrs(struct module *mod)
1006 {
1007 if (mod->sect_attrs) {
1008 sysfs_remove_group(&mod->mkobj.kobj,
1009 &mod->sect_attrs->grp);
1010 /* We are positive that no one is using any sect attrs
1011 * at this point. Deallocate immediately. */
1012 free_sect_attrs(mod->sect_attrs);
1013 mod->sect_attrs = NULL;
1014 }
1015 }
1016
1017 #else
1018
1019 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1020 char *sectstrings, Elf_Shdr *sechdrs)
1021 {
1022 }
1023
1024 static inline void remove_sect_attrs(struct module *mod)
1025 {
1026 }
1027 #endif /* CONFIG_KALLSYMS */
1028
1029 static int module_add_modinfo_attrs(struct module *mod)
1030 {
1031 struct module_attribute *attr;
1032 struct module_attribute *temp_attr;
1033 int error = 0;
1034 int i;
1035
1036 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1037 (ARRAY_SIZE(modinfo_attrs) + 1)),
1038 GFP_KERNEL);
1039 if (!mod->modinfo_attrs)
1040 return -ENOMEM;
1041
1042 temp_attr = mod->modinfo_attrs;
1043 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1044 if (!attr->test ||
1045 (attr->test && attr->test(mod))) {
1046 memcpy(temp_attr, attr, sizeof(*temp_attr));
1047 temp_attr->attr.owner = mod;
1048 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1049 ++temp_attr;
1050 }
1051 }
1052 return error;
1053 }
1054
1055 static void module_remove_modinfo_attrs(struct module *mod)
1056 {
1057 struct module_attribute *attr;
1058 int i;
1059
1060 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1061 /* pick a field to test for end of list */
1062 if (!attr->attr.name)
1063 break;
1064 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1065 if (attr->free)
1066 attr->free(mod);
1067 }
1068 kfree(mod->modinfo_attrs);
1069 }
1070
1071 static int mod_sysfs_setup(struct module *mod,
1072 struct kernel_param *kparam,
1073 unsigned int num_params)
1074 {
1075 int err;
1076
1077 if (!module_subsys.kset.subsys) {
1078 printk(KERN_ERR "%s: module_subsys not initialized\n",
1079 mod->name);
1080 err = -EINVAL;
1081 goto out;
1082 }
1083 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1084 err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name);
1085 if (err)
1086 goto out;
1087 kobj_set_kset_s(&mod->mkobj, module_subsys);
1088 mod->mkobj.mod = mod;
1089
1090 /* delay uevent until full sysfs population */
1091 kobject_init(&mod->mkobj.kobj);
1092 err = kobject_add(&mod->mkobj.kobj);
1093 if (err)
1094 goto out;
1095
1096 mod->drivers_dir = kobject_add_dir(&mod->mkobj.kobj, "drivers");
1097 if (!mod->drivers_dir)
1098 goto out_unreg;
1099
1100 err = module_param_sysfs_setup(mod, kparam, num_params);
1101 if (err)
1102 goto out_unreg_drivers;
1103
1104 err = module_add_modinfo_attrs(mod);
1105 if (err)
1106 goto out_unreg_param;
1107
1108 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1109 return 0;
1110
1111 out_unreg_drivers:
1112 kobject_unregister(mod->drivers_dir);
1113 out_unreg_param:
1114 module_param_sysfs_remove(mod);
1115 out_unreg:
1116 kobject_del(&mod->mkobj.kobj);
1117 kobject_put(&mod->mkobj.kobj);
1118 out:
1119 return err;
1120 }
1121
1122 static void mod_kobject_remove(struct module *mod)
1123 {
1124 module_remove_modinfo_attrs(mod);
1125 module_param_sysfs_remove(mod);
1126 kobject_unregister(mod->drivers_dir);
1127
1128 kobject_unregister(&mod->mkobj.kobj);
1129 }
1130
1131 /*
1132 * unlink the module with the whole machine is stopped with interrupts off
1133 * - this defends against kallsyms not taking locks
1134 */
1135 static int __unlink_module(void *_mod)
1136 {
1137 struct module *mod = _mod;
1138 list_del(&mod->list);
1139 return 0;
1140 }
1141
1142 /* Free a module, remove from lists, etc (must hold module mutex). */
1143 static void free_module(struct module *mod)
1144 {
1145 /* Delete from various lists */
1146 stop_machine_run(__unlink_module, mod, NR_CPUS);
1147 remove_sect_attrs(mod);
1148 mod_kobject_remove(mod);
1149
1150 unwind_remove_table(mod->unwind_info, 0);
1151
1152 /* Arch-specific cleanup. */
1153 module_arch_cleanup(mod);
1154
1155 /* Module unload stuff */
1156 module_unload_free(mod);
1157
1158 /* This may be NULL, but that's OK */
1159 module_free(mod, mod->module_init);
1160 kfree(mod->args);
1161 if (mod->percpu)
1162 percpu_modfree(mod->percpu);
1163
1164 /* Free lock-classes: */
1165 lockdep_free_key_range(mod->module_core, mod->core_size);
1166
1167 /* Finally, free the core (containing the module structure) */
1168 module_free(mod, mod->module_core);
1169 }
1170
1171 void *__symbol_get(const char *symbol)
1172 {
1173 struct module *owner;
1174 unsigned long value, flags;
1175 const unsigned long *crc;
1176
1177 spin_lock_irqsave(&modlist_lock, flags);
1178 value = __find_symbol(symbol, &owner, &crc, 1);
1179 if (value && !strong_try_module_get(owner))
1180 value = 0;
1181 spin_unlock_irqrestore(&modlist_lock, flags);
1182
1183 return (void *)value;
1184 }
1185 EXPORT_SYMBOL_GPL(__symbol_get);
1186
1187 /*
1188 * Ensure that an exported symbol [global namespace] does not already exist
1189 * in the Kernel or in some other modules exported symbol table.
1190 */
1191 static int verify_export_symbols(struct module *mod)
1192 {
1193 const char *name = NULL;
1194 unsigned long i, ret = 0;
1195 struct module *owner;
1196 const unsigned long *crc;
1197
1198 for (i = 0; i < mod->num_syms; i++)
1199 if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) {
1200 name = mod->syms[i].name;
1201 ret = -ENOEXEC;
1202 goto dup;
1203 }
1204
1205 for (i = 0; i < mod->num_gpl_syms; i++)
1206 if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) {
1207 name = mod->gpl_syms[i].name;
1208 ret = -ENOEXEC;
1209 goto dup;
1210 }
1211
1212 dup:
1213 if (ret)
1214 printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
1215 mod->name, name, module_name(owner));
1216
1217 return ret;
1218 }
1219
1220 /* Change all symbols so that sh_value encodes the pointer directly. */
1221 static int simplify_symbols(Elf_Shdr *sechdrs,
1222 unsigned int symindex,
1223 const char *strtab,
1224 unsigned int versindex,
1225 unsigned int pcpuindex,
1226 struct module *mod)
1227 {
1228 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1229 unsigned long secbase;
1230 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1231 int ret = 0;
1232
1233 for (i = 1; i < n; i++) {
1234 switch (sym[i].st_shndx) {
1235 case SHN_COMMON:
1236 /* We compiled with -fno-common. These are not
1237 supposed to happen. */
1238 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1239 printk("%s: please compile with -fno-common\n",
1240 mod->name);
1241 ret = -ENOEXEC;
1242 break;
1243
1244 case SHN_ABS:
1245 /* Don't need to do anything */
1246 DEBUGP("Absolute symbol: 0x%08lx\n",
1247 (long)sym[i].st_value);
1248 break;
1249
1250 case SHN_UNDEF:
1251 sym[i].st_value
1252 = resolve_symbol(sechdrs, versindex,
1253 strtab + sym[i].st_name, mod);
1254
1255 /* Ok if resolved. */
1256 if (sym[i].st_value != 0)
1257 break;
1258 /* Ok if weak. */
1259 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1260 break;
1261
1262 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1263 mod->name, strtab + sym[i].st_name);
1264 ret = -ENOENT;
1265 break;
1266
1267 default:
1268 /* Divert to percpu allocation if a percpu var. */
1269 if (sym[i].st_shndx == pcpuindex)
1270 secbase = (unsigned long)mod->percpu;
1271 else
1272 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1273 sym[i].st_value += secbase;
1274 break;
1275 }
1276 }
1277
1278 return ret;
1279 }
1280
1281 /* Update size with this section: return offset. */
1282 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
1283 {
1284 long ret;
1285
1286 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1287 *size = ret + sechdr->sh_size;
1288 return ret;
1289 }
1290
1291 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1292 might -- code, read-only data, read-write data, small data. Tally
1293 sizes, and place the offsets into sh_entsize fields: high bit means it
1294 belongs in init. */
1295 static void layout_sections(struct module *mod,
1296 const Elf_Ehdr *hdr,
1297 Elf_Shdr *sechdrs,
1298 const char *secstrings)
1299 {
1300 static unsigned long const masks[][2] = {
1301 /* NOTE: all executable code must be the first section
1302 * in this array; otherwise modify the text_size
1303 * finder in the two loops below */
1304 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1305 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1306 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1307 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1308 };
1309 unsigned int m, i;
1310
1311 for (i = 0; i < hdr->e_shnum; i++)
1312 sechdrs[i].sh_entsize = ~0UL;
1313
1314 DEBUGP("Core section allocation order:\n");
1315 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1316 for (i = 0; i < hdr->e_shnum; ++i) {
1317 Elf_Shdr *s = &sechdrs[i];
1318
1319 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1320 || (s->sh_flags & masks[m][1])
1321 || s->sh_entsize != ~0UL
1322 || strncmp(secstrings + s->sh_name,
1323 ".init", 5) == 0)
1324 continue;
1325 s->sh_entsize = get_offset(&mod->core_size, s);
1326 DEBUGP("\t%s\n", secstrings + s->sh_name);
1327 }
1328 if (m == 0)
1329 mod->core_text_size = mod->core_size;
1330 }
1331
1332 DEBUGP("Init section allocation order:\n");
1333 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1334 for (i = 0; i < hdr->e_shnum; ++i) {
1335 Elf_Shdr *s = &sechdrs[i];
1336
1337 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1338 || (s->sh_flags & masks[m][1])
1339 || s->sh_entsize != ~0UL
1340 || strncmp(secstrings + s->sh_name,
1341 ".init", 5) != 0)
1342 continue;
1343 s->sh_entsize = (get_offset(&mod->init_size, s)
1344 | INIT_OFFSET_MASK);
1345 DEBUGP("\t%s\n", secstrings + s->sh_name);
1346 }
1347 if (m == 0)
1348 mod->init_text_size = mod->init_size;
1349 }
1350 }
1351
1352 static void set_license(struct module *mod, const char *license)
1353 {
1354 if (!license)
1355 license = "unspecified";
1356
1357 if (!license_is_gpl_compatible(license)) {
1358 if (!(tainted & TAINT_PROPRIETARY_MODULE))
1359 printk(KERN_WARNING "%s: module license '%s' taints "
1360 "kernel.\n", mod->name, license);
1361 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1362 }
1363 }
1364
1365 /* Parse tag=value strings from .modinfo section */
1366 static char *next_string(char *string, unsigned long *secsize)
1367 {
1368 /* Skip non-zero chars */
1369 while (string[0]) {
1370 string++;
1371 if ((*secsize)-- <= 1)
1372 return NULL;
1373 }
1374
1375 /* Skip any zero padding. */
1376 while (!string[0]) {
1377 string++;
1378 if ((*secsize)-- <= 1)
1379 return NULL;
1380 }
1381 return string;
1382 }
1383
1384 static char *get_modinfo(Elf_Shdr *sechdrs,
1385 unsigned int info,
1386 const char *tag)
1387 {
1388 char *p;
1389 unsigned int taglen = strlen(tag);
1390 unsigned long size = sechdrs[info].sh_size;
1391
1392 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1393 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1394 return p + taglen + 1;
1395 }
1396 return NULL;
1397 }
1398
1399 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1400 unsigned int infoindex)
1401 {
1402 struct module_attribute *attr;
1403 int i;
1404
1405 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1406 if (attr->setup)
1407 attr->setup(mod,
1408 get_modinfo(sechdrs,
1409 infoindex,
1410 attr->attr.name));
1411 }
1412 }
1413
1414 #ifdef CONFIG_KALLSYMS
1415 int is_exported(const char *name, const struct module *mod)
1416 {
1417 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1418 return 1;
1419 else
1420 if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1421 return 1;
1422 else
1423 return 0;
1424 }
1425
1426 /* As per nm */
1427 static char elf_type(const Elf_Sym *sym,
1428 Elf_Shdr *sechdrs,
1429 const char *secstrings,
1430 struct module *mod)
1431 {
1432 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1433 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1434 return 'v';
1435 else
1436 return 'w';
1437 }
1438 if (sym->st_shndx == SHN_UNDEF)
1439 return 'U';
1440 if (sym->st_shndx == SHN_ABS)
1441 return 'a';
1442 if (sym->st_shndx >= SHN_LORESERVE)
1443 return '?';
1444 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1445 return 't';
1446 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1447 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1448 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1449 return 'r';
1450 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1451 return 'g';
1452 else
1453 return 'd';
1454 }
1455 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1456 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1457 return 's';
1458 else
1459 return 'b';
1460 }
1461 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1462 ".debug", strlen(".debug")) == 0)
1463 return 'n';
1464 return '?';
1465 }
1466
1467 static void add_kallsyms(struct module *mod,
1468 Elf_Shdr *sechdrs,
1469 unsigned int symindex,
1470 unsigned int strindex,
1471 const char *secstrings)
1472 {
1473 unsigned int i;
1474
1475 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1476 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1477 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1478
1479 /* Set types up while we still have access to sections. */
1480 for (i = 0; i < mod->num_symtab; i++)
1481 mod->symtab[i].st_info
1482 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1483 }
1484 #else
1485 static inline void add_kallsyms(struct module *mod,
1486 Elf_Shdr *sechdrs,
1487 unsigned int symindex,
1488 unsigned int strindex,
1489 const char *secstrings)
1490 {
1491 }
1492 #endif /* CONFIG_KALLSYMS */
1493
1494 /* Allocate and load the module: note that size of section 0 is always
1495 zero, and we rely on this for optional sections. */
1496 static struct module *load_module(void __user *umod,
1497 unsigned long len,
1498 const char __user *uargs)
1499 {
1500 Elf_Ehdr *hdr;
1501 Elf_Shdr *sechdrs;
1502 char *secstrings, *args, *modmagic, *strtab = NULL;
1503 unsigned int i;
1504 unsigned int symindex = 0;
1505 unsigned int strindex = 0;
1506 unsigned int setupindex;
1507 unsigned int exindex;
1508 unsigned int exportindex;
1509 unsigned int modindex;
1510 unsigned int obsparmindex;
1511 unsigned int infoindex;
1512 unsigned int gplindex;
1513 unsigned int crcindex;
1514 unsigned int gplcrcindex;
1515 unsigned int versindex;
1516 unsigned int pcpuindex;
1517 unsigned int gplfutureindex;
1518 unsigned int gplfuturecrcindex;
1519 unsigned int unwindex = 0;
1520 unsigned int unusedindex;
1521 unsigned int unusedcrcindex;
1522 unsigned int unusedgplindex;
1523 unsigned int unusedgplcrcindex;
1524 struct module *mod;
1525 long err = 0;
1526 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1527 struct exception_table_entry *extable;
1528 mm_segment_t old_fs;
1529
1530 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1531 umod, len, uargs);
1532 if (len < sizeof(*hdr))
1533 return ERR_PTR(-ENOEXEC);
1534
1535 /* Suck in entire file: we'll want most of it. */
1536 /* vmalloc barfs on "unusual" numbers. Check here */
1537 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1538 return ERR_PTR(-ENOMEM);
1539 if (copy_from_user(hdr, umod, len) != 0) {
1540 err = -EFAULT;
1541 goto free_hdr;
1542 }
1543
1544 /* Sanity checks against insmoding binaries or wrong arch,
1545 weird elf version */
1546 if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
1547 || hdr->e_type != ET_REL
1548 || !elf_check_arch(hdr)
1549 || hdr->e_shentsize != sizeof(*sechdrs)) {
1550 err = -ENOEXEC;
1551 goto free_hdr;
1552 }
1553
1554 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1555 goto truncated;
1556
1557 /* Convenience variables */
1558 sechdrs = (void *)hdr + hdr->e_shoff;
1559 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1560 sechdrs[0].sh_addr = 0;
1561
1562 for (i = 1; i < hdr->e_shnum; i++) {
1563 if (sechdrs[i].sh_type != SHT_NOBITS
1564 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1565 goto truncated;
1566
1567 /* Mark all sections sh_addr with their address in the
1568 temporary image. */
1569 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1570
1571 /* Internal symbols and strings. */
1572 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1573 symindex = i;
1574 strindex = sechdrs[i].sh_link;
1575 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1576 }
1577 #ifndef CONFIG_MODULE_UNLOAD
1578 /* Don't load .exit sections */
1579 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1580 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1581 #endif
1582 }
1583
1584 modindex = find_sec(hdr, sechdrs, secstrings,
1585 ".gnu.linkonce.this_module");
1586 if (!modindex) {
1587 printk(KERN_WARNING "No module found in object\n");
1588 err = -ENOEXEC;
1589 goto free_hdr;
1590 }
1591 mod = (void *)sechdrs[modindex].sh_addr;
1592
1593 if (symindex == 0) {
1594 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1595 mod->name);
1596 err = -ENOEXEC;
1597 goto free_hdr;
1598 }
1599
1600 /* Optional sections */
1601 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1602 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1603 gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1604 unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
1605 unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
1606 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1607 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1608 gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1609 unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
1610 unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
1611 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1612 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1613 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1614 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1615 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1616 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1617 #ifdef ARCH_UNWIND_SECTION_NAME
1618 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1619 #endif
1620
1621 /* Don't keep modinfo section */
1622 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1623 #ifdef CONFIG_KALLSYMS
1624 /* Keep symbol and string tables for decoding later. */
1625 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1626 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1627 #endif
1628 if (unwindex)
1629 sechdrs[unwindex].sh_flags |= SHF_ALLOC;
1630
1631 /* Check module struct version now, before we try to use module. */
1632 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1633 err = -ENOEXEC;
1634 goto free_hdr;
1635 }
1636
1637 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1638 /* This is allowed: modprobe --force will invalidate it. */
1639 if (!modmagic) {
1640 add_taint_module(mod, TAINT_FORCED_MODULE);
1641 printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
1642 mod->name);
1643 } else if (!same_magic(modmagic, vermagic)) {
1644 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1645 mod->name, modmagic, vermagic);
1646 err = -ENOEXEC;
1647 goto free_hdr;
1648 }
1649
1650 /* Now copy in args */
1651 args = strndup_user(uargs, ~0UL >> 1);
1652 if (IS_ERR(args)) {
1653 err = PTR_ERR(args);
1654 goto free_hdr;
1655 }
1656
1657 if (find_module(mod->name)) {
1658 err = -EEXIST;
1659 goto free_mod;
1660 }
1661
1662 mod->state = MODULE_STATE_COMING;
1663
1664 /* Allow arches to frob section contents and sizes. */
1665 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1666 if (err < 0)
1667 goto free_mod;
1668
1669 if (pcpuindex) {
1670 /* We have a special allocation for this section. */
1671 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1672 sechdrs[pcpuindex].sh_addralign,
1673 mod->name);
1674 if (!percpu) {
1675 err = -ENOMEM;
1676 goto free_mod;
1677 }
1678 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1679 mod->percpu = percpu;
1680 }
1681
1682 /* Determine total sizes, and put offsets in sh_entsize. For now
1683 this is done generically; there doesn't appear to be any
1684 special cases for the architectures. */
1685 layout_sections(mod, hdr, sechdrs, secstrings);
1686
1687 /* Do the allocs. */
1688 ptr = module_alloc(mod->core_size);
1689 if (!ptr) {
1690 err = -ENOMEM;
1691 goto free_percpu;
1692 }
1693 memset(ptr, 0, mod->core_size);
1694 mod->module_core = ptr;
1695
1696 ptr = module_alloc(mod->init_size);
1697 if (!ptr && mod->init_size) {
1698 err = -ENOMEM;
1699 goto free_core;
1700 }
1701 memset(ptr, 0, mod->init_size);
1702 mod->module_init = ptr;
1703
1704 /* Transfer each section which specifies SHF_ALLOC */
1705 DEBUGP("final section addresses:\n");
1706 for (i = 0; i < hdr->e_shnum; i++) {
1707 void *dest;
1708
1709 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1710 continue;
1711
1712 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
1713 dest = mod->module_init
1714 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
1715 else
1716 dest = mod->module_core + sechdrs[i].sh_entsize;
1717
1718 if (sechdrs[i].sh_type != SHT_NOBITS)
1719 memcpy(dest, (void *)sechdrs[i].sh_addr,
1720 sechdrs[i].sh_size);
1721 /* Update sh_addr to point to copy in image. */
1722 sechdrs[i].sh_addr = (unsigned long)dest;
1723 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
1724 }
1725 /* Module has been moved. */
1726 mod = (void *)sechdrs[modindex].sh_addr;
1727
1728 /* Now we've moved module, initialize linked lists, etc. */
1729 module_unload_init(mod);
1730
1731 /* Set up license info based on the info section */
1732 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
1733
1734 if (strcmp(mod->name, "ndiswrapper") == 0)
1735 add_taint(TAINT_PROPRIETARY_MODULE);
1736 if (strcmp(mod->name, "driverloader") == 0)
1737 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1738
1739 /* Set up MODINFO_ATTR fields */
1740 setup_modinfo(mod, sechdrs, infoindex);
1741
1742 /* Fix up syms, so that st_value is a pointer to location. */
1743 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
1744 mod);
1745 if (err < 0)
1746 goto cleanup;
1747
1748 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
1749 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
1750 mod->syms = (void *)sechdrs[exportindex].sh_addr;
1751 if (crcindex)
1752 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
1753 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
1754 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
1755 if (gplcrcindex)
1756 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
1757 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
1758 sizeof(*mod->gpl_future_syms);
1759 mod->num_unused_syms = sechdrs[unusedindex].sh_size /
1760 sizeof(*mod->unused_syms);
1761 mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
1762 sizeof(*mod->unused_gpl_syms);
1763 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
1764 if (gplfuturecrcindex)
1765 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
1766
1767 mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
1768 if (unusedcrcindex)
1769 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
1770 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
1771 if (unusedgplcrcindex)
1772 mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr;
1773
1774 #ifdef CONFIG_MODVERSIONS
1775 if ((mod->num_syms && !crcindex) ||
1776 (mod->num_gpl_syms && !gplcrcindex) ||
1777 (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
1778 (mod->num_unused_syms && !unusedcrcindex) ||
1779 (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
1780 printk(KERN_WARNING "%s: No versions for exported symbols."
1781 " Tainting kernel.\n", mod->name);
1782 add_taint_module(mod, TAINT_FORCED_MODULE);
1783 }
1784 #endif
1785
1786 /* Now do relocations. */
1787 for (i = 1; i < hdr->e_shnum; i++) {
1788 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1789 unsigned int info = sechdrs[i].sh_info;
1790
1791 /* Not a valid relocation section? */
1792 if (info >= hdr->e_shnum)
1793 continue;
1794
1795 /* Don't bother with non-allocated sections */
1796 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1797 continue;
1798
1799 if (sechdrs[i].sh_type == SHT_REL)
1800 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
1801 else if (sechdrs[i].sh_type == SHT_RELA)
1802 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1803 mod);
1804 if (err < 0)
1805 goto cleanup;
1806 }
1807
1808 /* Find duplicate symbols */
1809 err = verify_export_symbols(mod);
1810
1811 if (err < 0)
1812 goto cleanup;
1813
1814 /* Set up and sort exception table */
1815 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
1816 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
1817 sort_extable(extable, extable + mod->num_exentries);
1818
1819 /* Finally, copy percpu area over. */
1820 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
1821 sechdrs[pcpuindex].sh_size);
1822
1823 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
1824
1825 err = module_finalize(hdr, sechdrs, mod);
1826 if (err < 0)
1827 goto cleanup;
1828
1829 /* flush the icache in correct context */
1830 old_fs = get_fs();
1831 set_fs(KERNEL_DS);
1832
1833 /*
1834 * Flush the instruction cache, since we've played with text.
1835 * Do it before processing of module parameters, so the module
1836 * can provide parameter accessor functions of its own.
1837 */
1838 if (mod->module_init)
1839 flush_icache_range((unsigned long)mod->module_init,
1840 (unsigned long)mod->module_init
1841 + mod->init_size);
1842 flush_icache_range((unsigned long)mod->module_core,
1843 (unsigned long)mod->module_core + mod->core_size);
1844
1845 set_fs(old_fs);
1846
1847 mod->args = args;
1848 if (obsparmindex)
1849 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
1850 mod->name);
1851
1852 /* Size of section 0 is 0, so this works well if no params */
1853 err = parse_args(mod->name, mod->args,
1854 (struct kernel_param *)
1855 sechdrs[setupindex].sh_addr,
1856 sechdrs[setupindex].sh_size
1857 / sizeof(struct kernel_param),
1858 NULL);
1859 if (err < 0)
1860 goto arch_cleanup;
1861
1862 err = mod_sysfs_setup(mod,
1863 (struct kernel_param *)
1864 sechdrs[setupindex].sh_addr,
1865 sechdrs[setupindex].sh_size
1866 / sizeof(struct kernel_param));
1867 if (err < 0)
1868 goto arch_cleanup;
1869 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
1870
1871 /* Size of section 0 is 0, so this works well if no unwind info. */
1872 mod->unwind_info = unwind_add_table(mod,
1873 (void *)sechdrs[unwindex].sh_addr,
1874 sechdrs[unwindex].sh_size);
1875
1876 /* Get rid of temporary copy */
1877 vfree(hdr);
1878
1879 /* Done! */
1880 return mod;
1881
1882 arch_cleanup:
1883 module_arch_cleanup(mod);
1884 cleanup:
1885 module_unload_free(mod);
1886 module_free(mod, mod->module_init);
1887 free_core:
1888 module_free(mod, mod->module_core);
1889 free_percpu:
1890 if (percpu)
1891 percpu_modfree(percpu);
1892 free_mod:
1893 kfree(args);
1894 free_hdr:
1895 vfree(hdr);
1896 return ERR_PTR(err);
1897
1898 truncated:
1899 printk(KERN_ERR "Module len %lu truncated\n", len);
1900 err = -ENOEXEC;
1901 goto free_hdr;
1902 }
1903
1904 /*
1905 * link the module with the whole machine is stopped with interrupts off
1906 * - this defends against kallsyms not taking locks
1907 */
1908 static int __link_module(void *_mod)
1909 {
1910 struct module *mod = _mod;
1911 list_add(&mod->list, &modules);
1912 return 0;
1913 }
1914
1915 /* This is where the real work happens */
1916 asmlinkage long
1917 sys_init_module(void __user *umod,
1918 unsigned long len,
1919 const char __user *uargs)
1920 {
1921 struct module *mod;
1922 int ret = 0;
1923
1924 /* Must have permission */
1925 if (!capable(CAP_SYS_MODULE))
1926 return -EPERM;
1927
1928 /* Only one module load at a time, please */
1929 if (mutex_lock_interruptible(&module_mutex) != 0)
1930 return -EINTR;
1931
1932 /* Do all the hard work */
1933 mod = load_module(umod, len, uargs);
1934 if (IS_ERR(mod)) {
1935 mutex_unlock(&module_mutex);
1936 return PTR_ERR(mod);
1937 }
1938
1939 /* Now sew it into the lists. They won't access us, since
1940 strong_try_module_get() will fail. */
1941 stop_machine_run(__link_module, mod, NR_CPUS);
1942
1943 /* Drop lock so they can recurse */
1944 mutex_unlock(&module_mutex);
1945
1946 blocking_notifier_call_chain(&module_notify_list,
1947 MODULE_STATE_COMING, mod);
1948
1949 /* Start the module */
1950 if (mod->init != NULL)
1951 ret = mod->init();
1952 if (ret < 0) {
1953 /* Init routine failed: abort. Try to protect us from
1954 buggy refcounters. */
1955 mod->state = MODULE_STATE_GOING;
1956 synchronize_sched();
1957 if (mod->unsafe)
1958 printk(KERN_ERR "%s: module is now stuck!\n",
1959 mod->name);
1960 else {
1961 module_put(mod);
1962 mutex_lock(&module_mutex);
1963 free_module(mod);
1964 mutex_unlock(&module_mutex);
1965 }
1966 return ret;
1967 }
1968
1969 /* Now it's a first class citizen! */
1970 mutex_lock(&module_mutex);
1971 mod->state = MODULE_STATE_LIVE;
1972 /* Drop initial reference. */
1973 module_put(mod);
1974 unwind_remove_table(mod->unwind_info, 1);
1975 module_free(mod, mod->module_init);
1976 mod->module_init = NULL;
1977 mod->init_size = 0;
1978 mod->init_text_size = 0;
1979 mutex_unlock(&module_mutex);
1980
1981 return 0;
1982 }
1983
1984 static inline int within(unsigned long addr, void *start, unsigned long size)
1985 {
1986 return ((void *)addr >= start && (void *)addr < start + size);
1987 }
1988
1989 #ifdef CONFIG_KALLSYMS
1990 /*
1991 * This ignores the intensely annoying "mapping symbols" found
1992 * in ARM ELF files: $a, $t and $d.
1993 */
1994 static inline int is_arm_mapping_symbol(const char *str)
1995 {
1996 return str[0] == '$' && strchr("atd", str[1])
1997 && (str[2] == '\0' || str[2] == '.');
1998 }
1999
2000 static const char *get_ksymbol(struct module *mod,
2001 unsigned long addr,
2002 unsigned long *size,
2003 unsigned long *offset)
2004 {
2005 unsigned int i, best = 0;
2006 unsigned long nextval;
2007
2008 /* At worse, next value is at end of module */
2009 if (within(addr, mod->module_init, mod->init_size))
2010 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2011 else
2012 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2013
2014 /* Scan for closest preceeding symbol, and next symbol. (ELF
2015 starts real symbols at 1). */
2016 for (i = 1; i < mod->num_symtab; i++) {
2017 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2018 continue;
2019
2020 /* We ignore unnamed symbols: they're uninformative
2021 * and inserted at a whim. */
2022 if (mod->symtab[i].st_value <= addr
2023 && mod->symtab[i].st_value > mod->symtab[best].st_value
2024 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2025 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2026 best = i;
2027 if (mod->symtab[i].st_value > addr
2028 && mod->symtab[i].st_value < nextval
2029 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2030 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2031 nextval = mod->symtab[i].st_value;
2032 }
2033
2034 if (!best)
2035 return NULL;
2036
2037 *size = nextval - mod->symtab[best].st_value;
2038 *offset = addr - mod->symtab[best].st_value;
2039 return mod->strtab + mod->symtab[best].st_name;
2040 }
2041
2042 /* For kallsyms to ask for address resolution. NULL means not found.
2043 We don't lock, as this is used for oops resolution and races are a
2044 lesser concern. */
2045 const char *module_address_lookup(unsigned long addr,
2046 unsigned long *size,
2047 unsigned long *offset,
2048 char **modname)
2049 {
2050 struct module *mod;
2051
2052 list_for_each_entry(mod, &modules, list) {
2053 if (within(addr, mod->module_init, mod->init_size)
2054 || within(addr, mod->module_core, mod->core_size)) {
2055 if (modname)
2056 *modname = mod->name;
2057 return get_ksymbol(mod, addr, size, offset);
2058 }
2059 }
2060 return NULL;
2061 }
2062
2063 struct module *module_get_kallsym(unsigned int symnum, unsigned long *value,
2064 char *type, char *name, size_t namelen)
2065 {
2066 struct module *mod;
2067
2068 mutex_lock(&module_mutex);
2069 list_for_each_entry(mod, &modules, list) {
2070 if (symnum < mod->num_symtab) {
2071 *value = mod->symtab[symnum].st_value;
2072 *type = mod->symtab[symnum].st_info;
2073 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2074 namelen);
2075 mutex_unlock(&module_mutex);
2076 return mod;
2077 }
2078 symnum -= mod->num_symtab;
2079 }
2080 mutex_unlock(&module_mutex);
2081 return NULL;
2082 }
2083
2084 static unsigned long mod_find_symname(struct module *mod, const char *name)
2085 {
2086 unsigned int i;
2087
2088 for (i = 0; i < mod->num_symtab; i++)
2089 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2090 mod->symtab[i].st_info != 'U')
2091 return mod->symtab[i].st_value;
2092 return 0;
2093 }
2094
2095 /* Look for this name: can be of form module:name. */
2096 unsigned long module_kallsyms_lookup_name(const char *name)
2097 {
2098 struct module *mod;
2099 char *colon;
2100 unsigned long ret = 0;
2101
2102 /* Don't lock: we're in enough trouble already. */
2103 if ((colon = strchr(name, ':')) != NULL) {
2104 *colon = '\0';
2105 if ((mod = find_module(name)) != NULL)
2106 ret = mod_find_symname(mod, colon+1);
2107 *colon = ':';
2108 } else {
2109 list_for_each_entry(mod, &modules, list)
2110 if ((ret = mod_find_symname(mod, name)) != 0)
2111 break;
2112 }
2113 return ret;
2114 }
2115 #endif /* CONFIG_KALLSYMS */
2116
2117 /* Called by the /proc file system to return a list of modules. */
2118 static void *m_start(struct seq_file *m, loff_t *pos)
2119 {
2120 struct list_head *i;
2121 loff_t n = 0;
2122
2123 mutex_lock(&module_mutex);
2124 list_for_each(i, &modules) {
2125 if (n++ == *pos)
2126 break;
2127 }
2128 if (i == &modules)
2129 return NULL;
2130 return i;
2131 }
2132
2133 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2134 {
2135 struct list_head *i = p;
2136 (*pos)++;
2137 if (i->next == &modules)
2138 return NULL;
2139 return i->next;
2140 }
2141
2142 static void m_stop(struct seq_file *m, void *p)
2143 {
2144 mutex_unlock(&module_mutex);
2145 }
2146
2147 static char *taint_flags(unsigned int taints, char *buf)
2148 {
2149 int bx = 0;
2150
2151 if (taints) {
2152 buf[bx++] = '(';
2153 if (taints & TAINT_PROPRIETARY_MODULE)
2154 buf[bx++] = 'P';
2155 if (taints & TAINT_FORCED_MODULE)
2156 buf[bx++] = 'F';
2157 /*
2158 * TAINT_FORCED_RMMOD: could be added.
2159 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2160 * apply to modules.
2161 */
2162 buf[bx++] = ')';
2163 }
2164 buf[bx] = '\0';
2165
2166 return buf;
2167 }
2168
2169 static int m_show(struct seq_file *m, void *p)
2170 {
2171 struct module *mod = list_entry(p, struct module, list);
2172 char buf[8];
2173
2174 seq_printf(m, "%s %lu",
2175 mod->name, mod->init_size + mod->core_size);
2176 print_unload_info(m, mod);
2177
2178 /* Informative for users. */
2179 seq_printf(m, " %s",
2180 mod->state == MODULE_STATE_GOING ? "Unloading":
2181 mod->state == MODULE_STATE_COMING ? "Loading":
2182 "Live");
2183 /* Used by oprofile and other similar tools. */
2184 seq_printf(m, " 0x%p", mod->module_core);
2185
2186 /* Taints info */
2187 if (mod->taints)
2188 seq_printf(m, " %s", taint_flags(mod->taints, buf));
2189
2190 seq_printf(m, "\n");
2191 return 0;
2192 }
2193
2194 /* Format: modulename size refcount deps address
2195
2196 Where refcount is a number or -, and deps is a comma-separated list
2197 of depends or -.
2198 */
2199 struct seq_operations modules_op = {
2200 .start = m_start,
2201 .next = m_next,
2202 .stop = m_stop,
2203 .show = m_show
2204 };
2205
2206 /* Given an address, look for it in the module exception tables. */
2207 const struct exception_table_entry *search_module_extables(unsigned long addr)
2208 {
2209 unsigned long flags;
2210 const struct exception_table_entry *e = NULL;
2211 struct module *mod;
2212
2213 spin_lock_irqsave(&modlist_lock, flags);
2214 list_for_each_entry(mod, &modules, list) {
2215 if (mod->num_exentries == 0)
2216 continue;
2217
2218 e = search_extable(mod->extable,
2219 mod->extable + mod->num_exentries - 1,
2220 addr);
2221 if (e)
2222 break;
2223 }
2224 spin_unlock_irqrestore(&modlist_lock, flags);
2225
2226 /* Now, if we found one, we are running inside it now, hence
2227 we cannot unload the module, hence no refcnt needed. */
2228 return e;
2229 }
2230
2231 /*
2232 * Is this a valid module address?
2233 */
2234 int is_module_address(unsigned long addr)
2235 {
2236 unsigned long flags;
2237 struct module *mod;
2238
2239 spin_lock_irqsave(&modlist_lock, flags);
2240
2241 list_for_each_entry(mod, &modules, list) {
2242 if (within(addr, mod->module_core, mod->core_size)) {
2243 spin_unlock_irqrestore(&modlist_lock, flags);
2244 return 1;
2245 }
2246 }
2247
2248 spin_unlock_irqrestore(&modlist_lock, flags);
2249
2250 return 0;
2251 }
2252
2253
2254 /* Is this a valid kernel address? We don't grab the lock: we are oopsing. */
2255 struct module *__module_text_address(unsigned long addr)
2256 {
2257 struct module *mod;
2258
2259 list_for_each_entry(mod, &modules, list)
2260 if (within(addr, mod->module_init, mod->init_text_size)
2261 || within(addr, mod->module_core, mod->core_text_size))
2262 return mod;
2263 return NULL;
2264 }
2265
2266 struct module *module_text_address(unsigned long addr)
2267 {
2268 struct module *mod;
2269 unsigned long flags;
2270
2271 spin_lock_irqsave(&modlist_lock, flags);
2272 mod = __module_text_address(addr);
2273 spin_unlock_irqrestore(&modlist_lock, flags);
2274
2275 return mod;
2276 }
2277
2278 /* Don't grab lock, we're oopsing. */
2279 void print_modules(void)
2280 {
2281 struct module *mod;
2282 char buf[8];
2283
2284 printk("Modules linked in:");
2285 list_for_each_entry(mod, &modules, list)
2286 printk(" %s%s", mod->name, taint_flags(mod->taints, buf));
2287 printk("\n");
2288 }
2289
2290 void module_add_driver(struct module *mod, struct device_driver *drv)
2291 {
2292 int no_warn;
2293
2294 if (!mod || !drv)
2295 return;
2296
2297 /* Don't check return codes; these calls are idempotent */
2298 no_warn = sysfs_create_link(&drv->kobj, &mod->mkobj.kobj, "module");
2299 no_warn = sysfs_create_link(mod->drivers_dir, &drv->kobj, drv->name);
2300 }
2301 EXPORT_SYMBOL(module_add_driver);
2302
2303 void module_remove_driver(struct device_driver *drv)
2304 {
2305 if (!drv)
2306 return;
2307 sysfs_remove_link(&drv->kobj, "module");
2308 if (drv->owner && drv->owner->drivers_dir)
2309 sysfs_remove_link(drv->owner->drivers_dir, drv->name);
2310 }
2311 EXPORT_SYMBOL(module_remove_driver);
2312
2313 #ifdef CONFIG_MODVERSIONS
2314 /* Generate the signature for struct module here, too, for modversions. */
2315 void struct_module(struct module *mod) { return; }
2316 EXPORT_SYMBOL(struct_module);
2317 #endif
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