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[XFS] remove remaining VN_HOLD calls
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / kernel / module.c
blob61d212120df48e82a1b6521120fdbd428d983a81
1 /*
2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19 #include <linux/module.h>
20 #include <linux/moduleloader.h>
21 #include <linux/init.h>
22 #include <linux/kallsyms.h>
23 #include <linux/sysfs.h>
24 #include <linux/kernel.h>
25 #include <linux/slab.h>
26 #include <linux/vmalloc.h>
27 #include <linux/elf.h>
28 #include <linux/seq_file.h>
29 #include <linux/syscalls.h>
30 #include <linux/fcntl.h>
31 #include <linux/rcupdate.h>
32 #include <linux/capability.h>
33 #include <linux/cpu.h>
34 #include <linux/moduleparam.h>
35 #include <linux/errno.h>
36 #include <linux/err.h>
37 #include <linux/vermagic.h>
38 #include <linux/notifier.h>
39 #include <linux/sched.h>
40 #include <linux/stop_machine.h>
41 #include <linux/device.h>
42 #include <linux/string.h>
43 #include <linux/mutex.h>
44 #include <linux/unwind.h>
45 #include <asm/uaccess.h>
46 #include <asm/cacheflush.h>
47 #include <linux/license.h>
48 #include <asm/sections.h>
49
50 #if 0
51 #define DEBUGP printk
52 #else
53 #define DEBUGP(fmt , a...)
54 #endif
55
56 #ifndef ARCH_SHF_SMALL
57 #define ARCH_SHF_SMALL 0
58 #endif
59
60 /* If this is set, the section belongs in the init part of the module */
61 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
62
63 /* List of modules, protected by module_mutex or preempt_disable
64 * (add/delete uses stop_machine). */
65 static DEFINE_MUTEX(module_mutex);
66 static LIST_HEAD(modules);
67
68 /* Waiting for a module to finish initializing? */
69 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
70
71 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
72
73 /* Bounds of module allocation, for speeding __module_text_address */
74 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
75
76 int register_module_notifier(struct notifier_block * nb)
77 {
78 return blocking_notifier_chain_register(&module_notify_list, nb);
79 }
80 EXPORT_SYMBOL(register_module_notifier);
81
82 int unregister_module_notifier(struct notifier_block * nb)
83 {
84 return blocking_notifier_chain_unregister(&module_notify_list, nb);
85 }
86 EXPORT_SYMBOL(unregister_module_notifier);
87
88 /* We require a truly strong try_module_get(): 0 means failure due to
89 ongoing or failed initialization etc. */
90 static inline int strong_try_module_get(struct module *mod)
91 {
92 if (mod && mod->state == MODULE_STATE_COMING)
93 return -EBUSY;
94 if (try_module_get(mod))
95 return 0;
96 else
97 return -ENOENT;
98 }
99
100 static inline void add_taint_module(struct module *mod, unsigned flag)
101 {
102 add_taint(flag);
103 mod->taints |= flag;
104 }
105
106 /*
107 * A thread that wants to hold a reference to a module only while it
108 * is running can call this to safely exit. nfsd and lockd use this.
109 */
110 void __module_put_and_exit(struct module *mod, long code)
111 {
112 module_put(mod);
113 do_exit(code);
114 }
115 EXPORT_SYMBOL(__module_put_and_exit);
116
117 /* Find a module section: 0 means not found. */
118 static unsigned int find_sec(Elf_Ehdr *hdr,
119 Elf_Shdr *sechdrs,
120 const char *secstrings,
121 const char *name)
122 {
123 unsigned int i;
124
125 for (i = 1; i < hdr->e_shnum; i++)
126 /* Alloc bit cleared means "ignore it." */
127 if ((sechdrs[i].sh_flags & SHF_ALLOC)
128 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
129 return i;
130 return 0;
131 }
132
133 /* Provided by the linker */
134 extern const struct kernel_symbol __start___ksymtab[];
135 extern const struct kernel_symbol __stop___ksymtab[];
136 extern const struct kernel_symbol __start___ksymtab_gpl[];
137 extern const struct kernel_symbol __stop___ksymtab_gpl[];
138 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
139 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
140 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
141 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
142 extern const unsigned long __start___kcrctab[];
143 extern const unsigned long __start___kcrctab_gpl[];
144 extern const unsigned long __start___kcrctab_gpl_future[];
145 #ifdef CONFIG_UNUSED_SYMBOLS
146 extern const struct kernel_symbol __start___ksymtab_unused[];
147 extern const struct kernel_symbol __stop___ksymtab_unused[];
148 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
149 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
150 extern const unsigned long __start___kcrctab_unused[];
151 extern const unsigned long __start___kcrctab_unused_gpl[];
152 #endif
153
154 #ifndef CONFIG_MODVERSIONS
155 #define symversion(base, idx) NULL
156 #else
157 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
158 #endif
159
160 struct symsearch {
161 const struct kernel_symbol *start, *stop;
162 const unsigned long *crcs;
163 enum {
164 NOT_GPL_ONLY,
165 GPL_ONLY,
166 WILL_BE_GPL_ONLY,
167 } licence;
168 bool unused;
169 };
170
171 static bool each_symbol_in_section(const struct symsearch *arr,
172 unsigned int arrsize,
173 struct module *owner,
174 bool (*fn)(const struct symsearch *syms,
175 struct module *owner,
176 unsigned int symnum, void *data),
177 void *data)
178 {
179 unsigned int i, j;
180
181 for (j = 0; j < arrsize; j++) {
182 for (i = 0; i < arr[j].stop - arr[j].start; i++)
183 if (fn(&arr[j], owner, i, data))
184 return true;
185 }
186
187 return false;
188 }
189
190 /* Returns true as soon as fn returns true, otherwise false. */
191 static bool each_symbol(bool (*fn)(const struct symsearch *arr,
192 struct module *owner,
193 unsigned int symnum, void *data),
194 void *data)
195 {
196 struct module *mod;
197 const struct symsearch arr[] = {
198 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
199 NOT_GPL_ONLY, false },
200 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
201 __start___kcrctab_gpl,
202 GPL_ONLY, false },
203 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
204 __start___kcrctab_gpl_future,
205 WILL_BE_GPL_ONLY, false },
206 #ifdef CONFIG_UNUSED_SYMBOLS
207 { __start___ksymtab_unused, __stop___ksymtab_unused,
208 __start___kcrctab_unused,
209 NOT_GPL_ONLY, true },
210 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
211 __start___kcrctab_unused_gpl,
212 GPL_ONLY, true },
213 #endif
214 };
215
216 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
217 return true;
218
219 list_for_each_entry(mod, &modules, list) {
220 struct symsearch arr[] = {
221 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
222 NOT_GPL_ONLY, false },
223 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
224 mod->gpl_crcs,
225 GPL_ONLY, false },
226 { mod->gpl_future_syms,
227 mod->gpl_future_syms + mod->num_gpl_future_syms,
228 mod->gpl_future_crcs,
229 WILL_BE_GPL_ONLY, false },
230 #ifdef CONFIG_UNUSED_SYMBOLS
231 { mod->unused_syms,
232 mod->unused_syms + mod->num_unused_syms,
233 mod->unused_crcs,
234 NOT_GPL_ONLY, true },
235 { mod->unused_gpl_syms,
236 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
237 mod->unused_gpl_crcs,
238 GPL_ONLY, true },
239 #endif
240 };
241
242 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
243 return true;
244 }
245 return false;
246 }
247
248 struct find_symbol_arg {
249 /* Input */
250 const char *name;
251 bool gplok;
252 bool warn;
253
254 /* Output */
255 struct module *owner;
256 const unsigned long *crc;
257 unsigned long value;
258 };
259
260 static bool find_symbol_in_section(const struct symsearch *syms,
261 struct module *owner,
262 unsigned int symnum, void *data)
263 {
264 struct find_symbol_arg *fsa = data;
265
266 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
267 return false;
268
269 if (!fsa->gplok) {
270 if (syms->licence == GPL_ONLY)
271 return false;
272 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
273 printk(KERN_WARNING "Symbol %s is being used "
274 "by a non-GPL module, which will not "
275 "be allowed in the future\n", fsa->name);
276 printk(KERN_WARNING "Please see the file "
277 "Documentation/feature-removal-schedule.txt "
278 "in the kernel source tree for more details.\n");
279 }
280 }
281
282 #ifdef CONFIG_UNUSED_SYMBOLS
283 if (syms->unused && fsa->warn) {
284 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
285 "however this module is using it.\n", fsa->name);
286 printk(KERN_WARNING
287 "This symbol will go away in the future.\n");
288 printk(KERN_WARNING
289 "Please evalute if this is the right api to use and if "
290 "it really is, submit a report the linux kernel "
291 "mailinglist together with submitting your code for "
292 "inclusion.\n");
293 }
294 #endif
295
296 fsa->owner = owner;
297 fsa->crc = symversion(syms->crcs, symnum);
298 fsa->value = syms->start[symnum].value;
299 return true;
300 }
301
302 /* Find a symbol, return value, (optional) crc and (optional) module
303 * which owns it */
304 static unsigned long find_symbol(const char *name,
305 struct module **owner,
306 const unsigned long **crc,
307 bool gplok,
308 bool warn)
309 {
310 struct find_symbol_arg fsa;
311
312 fsa.name = name;
313 fsa.gplok = gplok;
314 fsa.warn = warn;
315
316 if (each_symbol(find_symbol_in_section, &fsa)) {
317 if (owner)
318 *owner = fsa.owner;
319 if (crc)
320 *crc = fsa.crc;
321 return fsa.value;
322 }
323
324 DEBUGP("Failed to find symbol %s\n", name);
325 return -ENOENT;
326 }
327
328 /* Search for module by name: must hold module_mutex. */
329 static struct module *find_module(const char *name)
330 {
331 struct module *mod;
332
333 list_for_each_entry(mod, &modules, list) {
334 if (strcmp(mod->name, name) == 0)
335 return mod;
336 }
337 return NULL;
338 }
339
340 #ifdef CONFIG_SMP
341 /* Number of blocks used and allocated. */
342 static unsigned int pcpu_num_used, pcpu_num_allocated;
343 /* Size of each block. -ve means used. */
344 static int *pcpu_size;
345
346 static int split_block(unsigned int i, unsigned short size)
347 {
348 /* Reallocation required? */
349 if (pcpu_num_used + 1 > pcpu_num_allocated) {
350 int *new;
351
352 new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2,
353 GFP_KERNEL);
354 if (!new)
355 return 0;
356
357 pcpu_num_allocated *= 2;
358 pcpu_size = new;
359 }
360
361 /* Insert a new subblock */
362 memmove(&pcpu_size[i+1], &pcpu_size[i],
363 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
364 pcpu_num_used++;
365
366 pcpu_size[i+1] -= size;
367 pcpu_size[i] = size;
368 return 1;
369 }
370
371 static inline unsigned int block_size(int val)
372 {
373 if (val < 0)
374 return -val;
375 return val;
376 }
377
378 static void *percpu_modalloc(unsigned long size, unsigned long align,
379 const char *name)
380 {
381 unsigned long extra;
382 unsigned int i;
383 void *ptr;
384
385 if (align > PAGE_SIZE) {
386 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
387 name, align, PAGE_SIZE);
388 align = PAGE_SIZE;
389 }
390
391 ptr = __per_cpu_start;
392 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
393 /* Extra for alignment requirement. */
394 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
395 BUG_ON(i == 0 && extra != 0);
396
397 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
398 continue;
399
400 /* Transfer extra to previous block. */
401 if (pcpu_size[i-1] < 0)
402 pcpu_size[i-1] -= extra;
403 else
404 pcpu_size[i-1] += extra;
405 pcpu_size[i] -= extra;
406 ptr += extra;
407
408 /* Split block if warranted */
409 if (pcpu_size[i] - size > sizeof(unsigned long))
410 if (!split_block(i, size))
411 return NULL;
412
413 /* Mark allocated */
414 pcpu_size[i] = -pcpu_size[i];
415 return ptr;
416 }
417
418 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
419 size);
420 return NULL;
421 }
422
423 static void percpu_modfree(void *freeme)
424 {
425 unsigned int i;
426 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
427
428 /* First entry is core kernel percpu data. */
429 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
430 if (ptr == freeme) {
431 pcpu_size[i] = -pcpu_size[i];
432 goto free;
433 }
434 }
435 BUG();
436
437 free:
438 /* Merge with previous? */
439 if (pcpu_size[i-1] >= 0) {
440 pcpu_size[i-1] += pcpu_size[i];
441 pcpu_num_used--;
442 memmove(&pcpu_size[i], &pcpu_size[i+1],
443 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
444 i--;
445 }
446 /* Merge with next? */
447 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
448 pcpu_size[i] += pcpu_size[i+1];
449 pcpu_num_used--;
450 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
451 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
452 }
453 }
454
455 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
456 Elf_Shdr *sechdrs,
457 const char *secstrings)
458 {
459 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
460 }
461
462 static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
463 {
464 int cpu;
465
466 for_each_possible_cpu(cpu)
467 memcpy(pcpudest + per_cpu_offset(cpu), from, size);
468 }
469
470 static int percpu_modinit(void)
471 {
472 pcpu_num_used = 2;
473 pcpu_num_allocated = 2;
474 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
475 GFP_KERNEL);
476 /* Static in-kernel percpu data (used). */
477 pcpu_size[0] = -(__per_cpu_end-__per_cpu_start);
478 /* Free room. */
479 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
480 if (pcpu_size[1] < 0) {
481 printk(KERN_ERR "No per-cpu room for modules.\n");
482 pcpu_num_used = 1;
483 }
484
485 return 0;
486 }
487 __initcall(percpu_modinit);
488 #else /* ... !CONFIG_SMP */
489 static inline void *percpu_modalloc(unsigned long size, unsigned long align,
490 const char *name)
491 {
492 return NULL;
493 }
494 static inline void percpu_modfree(void *pcpuptr)
495 {
496 BUG();
497 }
498 static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
499 Elf_Shdr *sechdrs,
500 const char *secstrings)
501 {
502 return 0;
503 }
504 static inline void percpu_modcopy(void *pcpudst, const void *src,
505 unsigned long size)
506 {
507 /* pcpusec should be 0, and size of that section should be 0. */
508 BUG_ON(size != 0);
509 }
510 #endif /* CONFIG_SMP */
511
512 #define MODINFO_ATTR(field) \
513 static void setup_modinfo_##field(struct module *mod, const char *s) \
514 { \
515 mod->field = kstrdup(s, GFP_KERNEL); \
516 } \
517 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
518 struct module *mod, char *buffer) \
519 { \
520 return sprintf(buffer, "%s\n", mod->field); \
521 } \
522 static int modinfo_##field##_exists(struct module *mod) \
523 { \
524 return mod->field != NULL; \
525 } \
526 static void free_modinfo_##field(struct module *mod) \
527 { \
528 kfree(mod->field); \
529 mod->field = NULL; \
530 } \
531 static struct module_attribute modinfo_##field = { \
532 .attr = { .name = __stringify(field), .mode = 0444 }, \
533 .show = show_modinfo_##field, \
534 .setup = setup_modinfo_##field, \
535 .test = modinfo_##field##_exists, \
536 .free = free_modinfo_##field, \
537 };
538
539 MODINFO_ATTR(version);
540 MODINFO_ATTR(srcversion);
541
542 static char last_unloaded_module[MODULE_NAME_LEN+1];
543
544 #ifdef CONFIG_MODULE_UNLOAD
545 /* Init the unload section of the module. */
546 static void module_unload_init(struct module *mod)
547 {
548 unsigned int i;
549
550 INIT_LIST_HEAD(&mod->modules_which_use_me);
551 for (i = 0; i < NR_CPUS; i++)
552 local_set(&mod->ref[i].count, 0);
553 /* Hold reference count during initialization. */
554 local_set(&mod->ref[raw_smp_processor_id()].count, 1);
555 /* Backwards compatibility macros put refcount during init. */
556 mod->waiter = current;
557 }
558
559 /* modules using other modules */
560 struct module_use
561 {
562 struct list_head list;
563 struct module *module_which_uses;
564 };
565
566 /* Does a already use b? */
567 static int already_uses(struct module *a, struct module *b)
568 {
569 struct module_use *use;
570
571 list_for_each_entry(use, &b->modules_which_use_me, list) {
572 if (use->module_which_uses == a) {
573 DEBUGP("%s uses %s!\n", a->name, b->name);
574 return 1;
575 }
576 }
577 DEBUGP("%s does not use %s!\n", a->name, b->name);
578 return 0;
579 }
580
581 /* Module a uses b */
582 static int use_module(struct module *a, struct module *b)
583 {
584 struct module_use *use;
585 int no_warn, err;
586
587 if (b == NULL || already_uses(a, b)) return 1;
588
589 /* If we're interrupted or time out, we fail. */
590 if (wait_event_interruptible_timeout(
591 module_wq, (err = strong_try_module_get(b)) != -EBUSY,
592 30 * HZ) <= 0) {
593 printk("%s: gave up waiting for init of module %s.\n",
594 a->name, b->name);
595 return 0;
596 }
597
598 /* If strong_try_module_get() returned a different error, we fail. */
599 if (err)
600 return 0;
601
602 DEBUGP("Allocating new usage for %s.\n", a->name);
603 use = kmalloc(sizeof(*use), GFP_ATOMIC);
604 if (!use) {
605 printk("%s: out of memory loading\n", a->name);
606 module_put(b);
607 return 0;
608 }
609
610 use->module_which_uses = a;
611 list_add(&use->list, &b->modules_which_use_me);
612 no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
613 return 1;
614 }
615
616 /* Clear the unload stuff of the module. */
617 static void module_unload_free(struct module *mod)
618 {
619 struct module *i;
620
621 list_for_each_entry(i, &modules, list) {
622 struct module_use *use;
623
624 list_for_each_entry(use, &i->modules_which_use_me, list) {
625 if (use->module_which_uses == mod) {
626 DEBUGP("%s unusing %s\n", mod->name, i->name);
627 module_put(i);
628 list_del(&use->list);
629 kfree(use);
630 sysfs_remove_link(i->holders_dir, mod->name);
631 /* There can be at most one match. */
632 break;
633 }
634 }
635 }
636 }
637
638 #ifdef CONFIG_MODULE_FORCE_UNLOAD
639 static inline int try_force_unload(unsigned int flags)
640 {
641 int ret = (flags & O_TRUNC);
642 if (ret)
643 add_taint(TAINT_FORCED_RMMOD);
644 return ret;
645 }
646 #else
647 static inline int try_force_unload(unsigned int flags)
648 {
649 return 0;
650 }
651 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
652
653 struct stopref
654 {
655 struct module *mod;
656 int flags;
657 int *forced;
658 };
659
660 /* Whole machine is stopped with interrupts off when this runs. */
661 static int __try_stop_module(void *_sref)
662 {
663 struct stopref *sref = _sref;
664
665 /* If it's not unused, quit unless we're forcing. */
666 if (module_refcount(sref->mod) != 0) {
667 if (!(*sref->forced = try_force_unload(sref->flags)))
668 return -EWOULDBLOCK;
669 }
670
671 /* Mark it as dying. */
672 sref->mod->state = MODULE_STATE_GOING;
673 return 0;
674 }
675
676 static int try_stop_module(struct module *mod, int flags, int *forced)
677 {
678 if (flags & O_NONBLOCK) {
679 struct stopref sref = { mod, flags, forced };
680
681 return stop_machine(__try_stop_module, &sref, NULL);
682 } else {
683 /* We don't need to stop the machine for this. */
684 mod->state = MODULE_STATE_GOING;
685 synchronize_sched();
686 return 0;
687 }
688 }
689
690 unsigned int module_refcount(struct module *mod)
691 {
692 unsigned int i, total = 0;
693
694 for (i = 0; i < NR_CPUS; i++)
695 total += local_read(&mod->ref[i].count);
696 return total;
697 }
698 EXPORT_SYMBOL(module_refcount);
699
700 /* This exists whether we can unload or not */
701 static void free_module(struct module *mod);
702
703 static void wait_for_zero_refcount(struct module *mod)
704 {
705 /* Since we might sleep for some time, release the mutex first */
706 mutex_unlock(&module_mutex);
707 for (;;) {
708 DEBUGP("Looking at refcount...\n");
709 set_current_state(TASK_UNINTERRUPTIBLE);
710 if (module_refcount(mod) == 0)
711 break;
712 schedule();
713 }
714 current->state = TASK_RUNNING;
715 mutex_lock(&module_mutex);
716 }
717
718 asmlinkage long
719 sys_delete_module(const char __user *name_user, unsigned int flags)
720 {
721 struct module *mod;
722 char name[MODULE_NAME_LEN];
723 int ret, forced = 0;
724
725 if (!capable(CAP_SYS_MODULE))
726 return -EPERM;
727
728 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
729 return -EFAULT;
730 name[MODULE_NAME_LEN-1] = '\0';
731
732 if (mutex_lock_interruptible(&module_mutex) != 0)
733 return -EINTR;
734
735 mod = find_module(name);
736 if (!mod) {
737 ret = -ENOENT;
738 goto out;
739 }
740
741 if (!list_empty(&mod->modules_which_use_me)) {
742 /* Other modules depend on us: get rid of them first. */
743 ret = -EWOULDBLOCK;
744 goto out;
745 }
746
747 /* Doing init or already dying? */
748 if (mod->state != MODULE_STATE_LIVE) {
749 /* FIXME: if (force), slam module count and wake up
750 waiter --RR */
751 DEBUGP("%s already dying\n", mod->name);
752 ret = -EBUSY;
753 goto out;
754 }
755
756 /* If it has an init func, it must have an exit func to unload */
757 if (mod->init && !mod->exit) {
758 forced = try_force_unload(flags);
759 if (!forced) {
760 /* This module can't be removed */
761 ret = -EBUSY;
762 goto out;
763 }
764 }
765
766 /* Set this up before setting mod->state */
767 mod->waiter = current;
768
769 /* Stop the machine so refcounts can't move and disable module. */
770 ret = try_stop_module(mod, flags, &forced);
771 if (ret != 0)
772 goto out;
773
774 /* Never wait if forced. */
775 if (!forced && module_refcount(mod) != 0)
776 wait_for_zero_refcount(mod);
777
778 mutex_unlock(&module_mutex);
779 /* Final destruction now noone is using it. */
780 if (mod->exit != NULL)
781 mod->exit();
782 blocking_notifier_call_chain(&module_notify_list,
783 MODULE_STATE_GOING, mod);
784 mutex_lock(&module_mutex);
785 /* Store the name of the last unloaded module for diagnostic purposes */
786 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
787 free_module(mod);
788
789 out:
790 mutex_unlock(&module_mutex);
791 return ret;
792 }
793
794 static void print_unload_info(struct seq_file *m, struct module *mod)
795 {
796 struct module_use *use;
797 int printed_something = 0;
798
799 seq_printf(m, " %u ", module_refcount(mod));
800
801 /* Always include a trailing , so userspace can differentiate
802 between this and the old multi-field proc format. */
803 list_for_each_entry(use, &mod->modules_which_use_me, list) {
804 printed_something = 1;
805 seq_printf(m, "%s,", use->module_which_uses->name);
806 }
807
808 if (mod->init != NULL && mod->exit == NULL) {
809 printed_something = 1;
810 seq_printf(m, "[permanent],");
811 }
812
813 if (!printed_something)
814 seq_printf(m, "-");
815 }
816
817 void __symbol_put(const char *symbol)
818 {
819 struct module *owner;
820
821 preempt_disable();
822 if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false)))
823 BUG();
824 module_put(owner);
825 preempt_enable();
826 }
827 EXPORT_SYMBOL(__symbol_put);
828
829 void symbol_put_addr(void *addr)
830 {
831 struct module *modaddr;
832
833 if (core_kernel_text((unsigned long)addr))
834 return;
835
836 if (!(modaddr = module_text_address((unsigned long)addr)))
837 BUG();
838 module_put(modaddr);
839 }
840 EXPORT_SYMBOL_GPL(symbol_put_addr);
841
842 static ssize_t show_refcnt(struct module_attribute *mattr,
843 struct module *mod, char *buffer)
844 {
845 return sprintf(buffer, "%u\n", module_refcount(mod));
846 }
847
848 static struct module_attribute refcnt = {
849 .attr = { .name = "refcnt", .mode = 0444 },
850 .show = show_refcnt,
851 };
852
853 void module_put(struct module *module)
854 {
855 if (module) {
856 unsigned int cpu = get_cpu();
857 local_dec(&module->ref[cpu].count);
858 /* Maybe they're waiting for us to drop reference? */
859 if (unlikely(!module_is_live(module)))
860 wake_up_process(module->waiter);
861 put_cpu();
862 }
863 }
864 EXPORT_SYMBOL(module_put);
865
866 #else /* !CONFIG_MODULE_UNLOAD */
867 static void print_unload_info(struct seq_file *m, struct module *mod)
868 {
869 /* We don't know the usage count, or what modules are using. */
870 seq_printf(m, " - -");
871 }
872
873 static inline void module_unload_free(struct module *mod)
874 {
875 }
876
877 static inline int use_module(struct module *a, struct module *b)
878 {
879 return strong_try_module_get(b) == 0;
880 }
881
882 static inline void module_unload_init(struct module *mod)
883 {
884 }
885 #endif /* CONFIG_MODULE_UNLOAD */
886
887 static ssize_t show_initstate(struct module_attribute *mattr,
888 struct module *mod, char *buffer)
889 {
890 const char *state = "unknown";
891
892 switch (mod->state) {
893 case MODULE_STATE_LIVE:
894 state = "live";
895 break;
896 case MODULE_STATE_COMING:
897 state = "coming";
898 break;
899 case MODULE_STATE_GOING:
900 state = "going";
901 break;
902 }
903 return sprintf(buffer, "%s\n", state);
904 }
905
906 static struct module_attribute initstate = {
907 .attr = { .name = "initstate", .mode = 0444 },
908 .show = show_initstate,
909 };
910
911 static struct module_attribute *modinfo_attrs[] = {
912 &modinfo_version,
913 &modinfo_srcversion,
914 &initstate,
915 #ifdef CONFIG_MODULE_UNLOAD
916 &refcnt,
917 #endif
918 NULL,
919 };
920
921 static const char vermagic[] = VERMAGIC_STRING;
922
923 static int try_to_force_load(struct module *mod, const char *symname)
924 {
925 #ifdef CONFIG_MODULE_FORCE_LOAD
926 if (!(tainted & TAINT_FORCED_MODULE))
927 printk("%s: no version for \"%s\" found: kernel tainted.\n",
928 mod->name, symname);
929 add_taint_module(mod, TAINT_FORCED_MODULE);
930 return 0;
931 #else
932 return -ENOEXEC;
933 #endif
934 }
935
936 #ifdef CONFIG_MODVERSIONS
937 static int check_version(Elf_Shdr *sechdrs,
938 unsigned int versindex,
939 const char *symname,
940 struct module *mod,
941 const unsigned long *crc)
942 {
943 unsigned int i, num_versions;
944 struct modversion_info *versions;
945
946 /* Exporting module didn't supply crcs? OK, we're already tainted. */
947 if (!crc)
948 return 1;
949
950 /* No versions at all? modprobe --force does this. */
951 if (versindex == 0)
952 return try_to_force_load(mod, symname) == 0;
953
954 versions = (void *) sechdrs[versindex].sh_addr;
955 num_versions = sechdrs[versindex].sh_size
956 / sizeof(struct modversion_info);
957
958 for (i = 0; i < num_versions; i++) {
959 if (strcmp(versions[i].name, symname) != 0)
960 continue;
961
962 if (versions[i].crc == *crc)
963 return 1;
964 DEBUGP("Found checksum %lX vs module %lX\n",
965 *crc, versions[i].crc);
966 goto bad_version;
967 }
968
969 printk(KERN_WARNING "%s: no symbol version for %s\n",
970 mod->name, symname);
971 return 0;
972
973 bad_version:
974 printk("%s: disagrees about version of symbol %s\n",
975 mod->name, symname);
976 return 0;
977 }
978
979 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
980 unsigned int versindex,
981 struct module *mod)
982 {
983 const unsigned long *crc;
984
985 if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false)))
986 BUG();
987 return check_version(sechdrs, versindex, "struct_module", mod, crc);
988 }
989
990 /* First part is kernel version, which we ignore if module has crcs. */
991 static inline int same_magic(const char *amagic, const char *bmagic,
992 bool has_crcs)
993 {
994 if (has_crcs) {
995 amagic += strcspn(amagic, " ");
996 bmagic += strcspn(bmagic, " ");
997 }
998 return strcmp(amagic, bmagic) == 0;
999 }
1000 #else
1001 static inline int check_version(Elf_Shdr *sechdrs,
1002 unsigned int versindex,
1003 const char *symname,
1004 struct module *mod,
1005 const unsigned long *crc)
1006 {
1007 return 1;
1008 }
1009
1010 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1011 unsigned int versindex,
1012 struct module *mod)
1013 {
1014 return 1;
1015 }
1016
1017 static inline int same_magic(const char *amagic, const char *bmagic,
1018 bool has_crcs)
1019 {
1020 return strcmp(amagic, bmagic) == 0;
1021 }
1022 #endif /* CONFIG_MODVERSIONS */
1023
1024 /* Resolve a symbol for this module. I.e. if we find one, record usage.
1025 Must be holding module_mutex. */
1026 static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
1027 unsigned int versindex,
1028 const char *name,
1029 struct module *mod)
1030 {
1031 struct module *owner;
1032 unsigned long ret;
1033 const unsigned long *crc;
1034
1035 ret = find_symbol(name, &owner, &crc,
1036 !(mod->taints & TAINT_PROPRIETARY_MODULE), true);
1037 if (!IS_ERR_VALUE(ret)) {
1038 /* use_module can fail due to OOM,
1039 or module initialization or unloading */
1040 if (!check_version(sechdrs, versindex, name, mod, crc) ||
1041 !use_module(mod, owner))
1042 ret = -EINVAL;
1043 }
1044 return ret;
1045 }
1046
1047 /*
1048 * /sys/module/foo/sections stuff
1049 * J. Corbet <corbet@lwn.net>
1050 */
1051 #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1052 struct module_sect_attr
1053 {
1054 struct module_attribute mattr;
1055 char *name;
1056 unsigned long address;
1057 };
1058
1059 struct module_sect_attrs
1060 {
1061 struct attribute_group grp;
1062 unsigned int nsections;
1063 struct module_sect_attr attrs[0];
1064 };
1065
1066 static ssize_t module_sect_show(struct module_attribute *mattr,
1067 struct module *mod, char *buf)
1068 {
1069 struct module_sect_attr *sattr =
1070 container_of(mattr, struct module_sect_attr, mattr);
1071 return sprintf(buf, "0x%lx\n", sattr->address);
1072 }
1073
1074 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1075 {
1076 unsigned int section;
1077
1078 for (section = 0; section < sect_attrs->nsections; section++)
1079 kfree(sect_attrs->attrs[section].name);
1080 kfree(sect_attrs);
1081 }
1082
1083 static void add_sect_attrs(struct module *mod, unsigned int nsect,
1084 char *secstrings, Elf_Shdr *sechdrs)
1085 {
1086 unsigned int nloaded = 0, i, size[2];
1087 struct module_sect_attrs *sect_attrs;
1088 struct module_sect_attr *sattr;
1089 struct attribute **gattr;
1090
1091 /* Count loaded sections and allocate structures */
1092 for (i = 0; i < nsect; i++)
1093 if (sechdrs[i].sh_flags & SHF_ALLOC)
1094 nloaded++;
1095 size[0] = ALIGN(sizeof(*sect_attrs)
1096 + nloaded * sizeof(sect_attrs->attrs[0]),
1097 sizeof(sect_attrs->grp.attrs[0]));
1098 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1099 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1100 if (sect_attrs == NULL)
1101 return;
1102
1103 /* Setup section attributes. */
1104 sect_attrs->grp.name = "sections";
1105 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1106
1107 sect_attrs->nsections = 0;
1108 sattr = &sect_attrs->attrs[0];
1109 gattr = &sect_attrs->grp.attrs[0];
1110 for (i = 0; i < nsect; i++) {
1111 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1112 continue;
1113 sattr->address = sechdrs[i].sh_addr;
1114 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1115 GFP_KERNEL);
1116 if (sattr->name == NULL)
1117 goto out;
1118 sect_attrs->nsections++;
1119 sattr->mattr.show = module_sect_show;
1120 sattr->mattr.store = NULL;
1121 sattr->mattr.attr.name = sattr->name;
1122 sattr->mattr.attr.mode = S_IRUGO;
1123 *(gattr++) = &(sattr++)->mattr.attr;
1124 }
1125 *gattr = NULL;
1126
1127 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1128 goto out;
1129
1130 mod->sect_attrs = sect_attrs;
1131 return;
1132 out:
1133 free_sect_attrs(sect_attrs);
1134 }
1135
1136 static void remove_sect_attrs(struct module *mod)
1137 {
1138 if (mod->sect_attrs) {
1139 sysfs_remove_group(&mod->mkobj.kobj,
1140 &mod->sect_attrs->grp);
1141 /* We are positive that no one is using any sect attrs
1142 * at this point. Deallocate immediately. */
1143 free_sect_attrs(mod->sect_attrs);
1144 mod->sect_attrs = NULL;
1145 }
1146 }
1147
1148 /*
1149 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1150 */
1151
1152 struct module_notes_attrs {
1153 struct kobject *dir;
1154 unsigned int notes;
1155 struct bin_attribute attrs[0];
1156 };
1157
1158 static ssize_t module_notes_read(struct kobject *kobj,
1159 struct bin_attribute *bin_attr,
1160 char *buf, loff_t pos, size_t count)
1161 {
1162 /*
1163 * The caller checked the pos and count against our size.
1164 */
1165 memcpy(buf, bin_attr->private + pos, count);
1166 return count;
1167 }
1168
1169 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1170 unsigned int i)
1171 {
1172 if (notes_attrs->dir) {
1173 while (i-- > 0)
1174 sysfs_remove_bin_file(notes_attrs->dir,
1175 &notes_attrs->attrs[i]);
1176 kobject_del(notes_attrs->dir);
1177 }
1178 kfree(notes_attrs);
1179 }
1180
1181 static void add_notes_attrs(struct module *mod, unsigned int nsect,
1182 char *secstrings, Elf_Shdr *sechdrs)
1183 {
1184 unsigned int notes, loaded, i;
1185 struct module_notes_attrs *notes_attrs;
1186 struct bin_attribute *nattr;
1187
1188 /* Count notes sections and allocate structures. */
1189 notes = 0;
1190 for (i = 0; i < nsect; i++)
1191 if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
1192 (sechdrs[i].sh_type == SHT_NOTE))
1193 ++notes;
1194
1195 if (notes == 0)
1196 return;
1197
1198 notes_attrs = kzalloc(sizeof(*notes_attrs)
1199 + notes * sizeof(notes_attrs->attrs[0]),
1200 GFP_KERNEL);
1201 if (notes_attrs == NULL)
1202 return;
1203
1204 notes_attrs->notes = notes;
1205 nattr = &notes_attrs->attrs[0];
1206 for (loaded = i = 0; i < nsect; ++i) {
1207 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1208 continue;
1209 if (sechdrs[i].sh_type == SHT_NOTE) {
1210 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1211 nattr->attr.mode = S_IRUGO;
1212 nattr->size = sechdrs[i].sh_size;
1213 nattr->private = (void *) sechdrs[i].sh_addr;
1214 nattr->read = module_notes_read;
1215 ++nattr;
1216 }
1217 ++loaded;
1218 }
1219
1220 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1221 if (!notes_attrs->dir)
1222 goto out;
1223
1224 for (i = 0; i < notes; ++i)
1225 if (sysfs_create_bin_file(notes_attrs->dir,
1226 &notes_attrs->attrs[i]))
1227 goto out;
1228
1229 mod->notes_attrs = notes_attrs;
1230 return;
1231
1232 out:
1233 free_notes_attrs(notes_attrs, i);
1234 }
1235
1236 static void remove_notes_attrs(struct module *mod)
1237 {
1238 if (mod->notes_attrs)
1239 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1240 }
1241
1242 #else
1243
1244 static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1245 char *sectstrings, Elf_Shdr *sechdrs)
1246 {
1247 }
1248
1249 static inline void remove_sect_attrs(struct module *mod)
1250 {
1251 }
1252
1253 static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1254 char *sectstrings, Elf_Shdr *sechdrs)
1255 {
1256 }
1257
1258 static inline void remove_notes_attrs(struct module *mod)
1259 {
1260 }
1261 #endif
1262
1263 #ifdef CONFIG_SYSFS
1264 int module_add_modinfo_attrs(struct module *mod)
1265 {
1266 struct module_attribute *attr;
1267 struct module_attribute *temp_attr;
1268 int error = 0;
1269 int i;
1270
1271 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1272 (ARRAY_SIZE(modinfo_attrs) + 1)),
1273 GFP_KERNEL);
1274 if (!mod->modinfo_attrs)
1275 return -ENOMEM;
1276
1277 temp_attr = mod->modinfo_attrs;
1278 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1279 if (!attr->test ||
1280 (attr->test && attr->test(mod))) {
1281 memcpy(temp_attr, attr, sizeof(*temp_attr));
1282 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1283 ++temp_attr;
1284 }
1285 }
1286 return error;
1287 }
1288
1289 void module_remove_modinfo_attrs(struct module *mod)
1290 {
1291 struct module_attribute *attr;
1292 int i;
1293
1294 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1295 /* pick a field to test for end of list */
1296 if (!attr->attr.name)
1297 break;
1298 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1299 if (attr->free)
1300 attr->free(mod);
1301 }
1302 kfree(mod->modinfo_attrs);
1303 }
1304
1305 int mod_sysfs_init(struct module *mod)
1306 {
1307 int err;
1308 struct kobject *kobj;
1309
1310 if (!module_sysfs_initialized) {
1311 printk(KERN_ERR "%s: module sysfs not initialized\n",
1312 mod->name);
1313 err = -EINVAL;
1314 goto out;
1315 }
1316
1317 kobj = kset_find_obj(module_kset, mod->name);
1318 if (kobj) {
1319 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1320 kobject_put(kobj);
1321 err = -EINVAL;
1322 goto out;
1323 }
1324
1325 mod->mkobj.mod = mod;
1326
1327 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1328 mod->mkobj.kobj.kset = module_kset;
1329 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1330 "%s", mod->name);
1331 if (err)
1332 kobject_put(&mod->mkobj.kobj);
1333
1334 /* delay uevent until full sysfs population */
1335 out:
1336 return err;
1337 }
1338
1339 int mod_sysfs_setup(struct module *mod,
1340 struct kernel_param *kparam,
1341 unsigned int num_params)
1342 {
1343 int err;
1344
1345 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1346 if (!mod->holders_dir) {
1347 err = -ENOMEM;
1348 goto out_unreg;
1349 }
1350
1351 err = module_param_sysfs_setup(mod, kparam, num_params);
1352 if (err)
1353 goto out_unreg_holders;
1354
1355 err = module_add_modinfo_attrs(mod);
1356 if (err)
1357 goto out_unreg_param;
1358
1359 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1360 return 0;
1361
1362 out_unreg_param:
1363 module_param_sysfs_remove(mod);
1364 out_unreg_holders:
1365 kobject_put(mod->holders_dir);
1366 out_unreg:
1367 kobject_put(&mod->mkobj.kobj);
1368 return err;
1369 }
1370
1371 static void mod_sysfs_fini(struct module *mod)
1372 {
1373 kobject_put(&mod->mkobj.kobj);
1374 }
1375
1376 #else /* CONFIG_SYSFS */
1377
1378 static void mod_sysfs_fini(struct module *mod)
1379 {
1380 }
1381
1382 #endif /* CONFIG_SYSFS */
1383
1384 static void mod_kobject_remove(struct module *mod)
1385 {
1386 module_remove_modinfo_attrs(mod);
1387 module_param_sysfs_remove(mod);
1388 kobject_put(mod->mkobj.drivers_dir);
1389 kobject_put(mod->holders_dir);
1390 mod_sysfs_fini(mod);
1391 }
1392
1393 /*
1394 * link the module with the whole machine is stopped with interrupts off
1395 * - this defends against kallsyms not taking locks
1396 */
1397 static int __link_module(void *_mod)
1398 {
1399 struct module *mod = _mod;
1400 list_add(&mod->list, &modules);
1401 return 0;
1402 }
1403
1404 /*
1405 * unlink the module with the whole machine is stopped with interrupts off
1406 * - this defends against kallsyms not taking locks
1407 */
1408 static int __unlink_module(void *_mod)
1409 {
1410 struct module *mod = _mod;
1411 list_del(&mod->list);
1412 return 0;
1413 }
1414
1415 /* Free a module, remove from lists, etc (must hold module_mutex). */
1416 static void free_module(struct module *mod)
1417 {
1418 /* Delete from various lists */
1419 stop_machine(__unlink_module, mod, NULL);
1420 remove_notes_attrs(mod);
1421 remove_sect_attrs(mod);
1422 mod_kobject_remove(mod);
1423
1424 unwind_remove_table(mod->unwind_info, 0);
1425
1426 /* Arch-specific cleanup. */
1427 module_arch_cleanup(mod);
1428
1429 /* Module unload stuff */
1430 module_unload_free(mod);
1431
1432 /* This may be NULL, but that's OK */
1433 module_free(mod, mod->module_init);
1434 kfree(mod->args);
1435 if (mod->percpu)
1436 percpu_modfree(mod->percpu);
1437
1438 /* Free lock-classes: */
1439 lockdep_free_key_range(mod->module_core, mod->core_size);
1440
1441 /* Finally, free the core (containing the module structure) */
1442 module_free(mod, mod->module_core);
1443 }
1444
1445 void *__symbol_get(const char *symbol)
1446 {
1447 struct module *owner;
1448 unsigned long value;
1449
1450 preempt_disable();
1451 value = find_symbol(symbol, &owner, NULL, true, true);
1452 if (IS_ERR_VALUE(value))
1453 value = 0;
1454 else if (strong_try_module_get(owner))
1455 value = 0;
1456 preempt_enable();
1457
1458 return (void *)value;
1459 }
1460 EXPORT_SYMBOL_GPL(__symbol_get);
1461
1462 /*
1463 * Ensure that an exported symbol [global namespace] does not already exist
1464 * in the kernel or in some other module's exported symbol table.
1465 */
1466 static int verify_export_symbols(struct module *mod)
1467 {
1468 unsigned int i;
1469 struct module *owner;
1470 const struct kernel_symbol *s;
1471 struct {
1472 const struct kernel_symbol *sym;
1473 unsigned int num;
1474 } arr[] = {
1475 { mod->syms, mod->num_syms },
1476 { mod->gpl_syms, mod->num_gpl_syms },
1477 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1478 #ifdef CONFIG_UNUSED_SYMBOLS
1479 { mod->unused_syms, mod->num_unused_syms },
1480 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1481 #endif
1482 };
1483
1484 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1485 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1486 if (!IS_ERR_VALUE(find_symbol(s->name, &owner,
1487 NULL, true, false))) {
1488 printk(KERN_ERR
1489 "%s: exports duplicate symbol %s"
1490 " (owned by %s)\n",
1491 mod->name, s->name, module_name(owner));
1492 return -ENOEXEC;
1493 }
1494 }
1495 }
1496 return 0;
1497 }
1498
1499 /* Change all symbols so that st_value encodes the pointer directly. */
1500 static int simplify_symbols(Elf_Shdr *sechdrs,
1501 unsigned int symindex,
1502 const char *strtab,
1503 unsigned int versindex,
1504 unsigned int pcpuindex,
1505 struct module *mod)
1506 {
1507 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1508 unsigned long secbase;
1509 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1510 int ret = 0;
1511
1512 for (i = 1; i < n; i++) {
1513 switch (sym[i].st_shndx) {
1514 case SHN_COMMON:
1515 /* We compiled with -fno-common. These are not
1516 supposed to happen. */
1517 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1518 printk("%s: please compile with -fno-common\n",
1519 mod->name);
1520 ret = -ENOEXEC;
1521 break;
1522
1523 case SHN_ABS:
1524 /* Don't need to do anything */
1525 DEBUGP("Absolute symbol: 0x%08lx\n",
1526 (long)sym[i].st_value);
1527 break;
1528
1529 case SHN_UNDEF:
1530 sym[i].st_value
1531 = resolve_symbol(sechdrs, versindex,
1532 strtab + sym[i].st_name, mod);
1533
1534 /* Ok if resolved. */
1535 if (!IS_ERR_VALUE(sym[i].st_value))
1536 break;
1537 /* Ok if weak. */
1538 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1539 break;
1540
1541 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1542 mod->name, strtab + sym[i].st_name);
1543 ret = -ENOENT;
1544 break;
1545
1546 default:
1547 /* Divert to percpu allocation if a percpu var. */
1548 if (sym[i].st_shndx == pcpuindex)
1549 secbase = (unsigned long)mod->percpu;
1550 else
1551 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1552 sym[i].st_value += secbase;
1553 break;
1554 }
1555 }
1556
1557 return ret;
1558 }
1559
1560 /* Update size with this section: return offset. */
1561 static long get_offset(unsigned int *size, Elf_Shdr *sechdr)
1562 {
1563 long ret;
1564
1565 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1566 *size = ret + sechdr->sh_size;
1567 return ret;
1568 }
1569
1570 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1571 might -- code, read-only data, read-write data, small data. Tally
1572 sizes, and place the offsets into sh_entsize fields: high bit means it
1573 belongs in init. */
1574 static void layout_sections(struct module *mod,
1575 const Elf_Ehdr *hdr,
1576 Elf_Shdr *sechdrs,
1577 const char *secstrings)
1578 {
1579 static unsigned long const masks[][2] = {
1580 /* NOTE: all executable code must be the first section
1581 * in this array; otherwise modify the text_size
1582 * finder in the two loops below */
1583 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1584 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1585 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1586 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1587 };
1588 unsigned int m, i;
1589
1590 for (i = 0; i < hdr->e_shnum; i++)
1591 sechdrs[i].sh_entsize = ~0UL;
1592
1593 DEBUGP("Core section allocation order:\n");
1594 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1595 for (i = 0; i < hdr->e_shnum; ++i) {
1596 Elf_Shdr *s = &sechdrs[i];
1597
1598 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1599 || (s->sh_flags & masks[m][1])
1600 || s->sh_entsize != ~0UL
1601 || strncmp(secstrings + s->sh_name,
1602 ".init", 5) == 0)
1603 continue;
1604 s->sh_entsize = get_offset(&mod->core_size, s);
1605 DEBUGP("\t%s\n", secstrings + s->sh_name);
1606 }
1607 if (m == 0)
1608 mod->core_text_size = mod->core_size;
1609 }
1610
1611 DEBUGP("Init section allocation order:\n");
1612 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1613 for (i = 0; i < hdr->e_shnum; ++i) {
1614 Elf_Shdr *s = &sechdrs[i];
1615
1616 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1617 || (s->sh_flags & masks[m][1])
1618 || s->sh_entsize != ~0UL
1619 || strncmp(secstrings + s->sh_name,
1620 ".init", 5) != 0)
1621 continue;
1622 s->sh_entsize = (get_offset(&mod->init_size, s)
1623 | INIT_OFFSET_MASK);
1624 DEBUGP("\t%s\n", secstrings + s->sh_name);
1625 }
1626 if (m == 0)
1627 mod->init_text_size = mod->init_size;
1628 }
1629 }
1630
1631 static void set_license(struct module *mod, const char *license)
1632 {
1633 if (!license)
1634 license = "unspecified";
1635
1636 if (!license_is_gpl_compatible(license)) {
1637 if (!(tainted & TAINT_PROPRIETARY_MODULE))
1638 printk(KERN_WARNING "%s: module license '%s' taints "
1639 "kernel.\n", mod->name, license);
1640 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1641 }
1642 }
1643
1644 /* Parse tag=value strings from .modinfo section */
1645 static char *next_string(char *string, unsigned long *secsize)
1646 {
1647 /* Skip non-zero chars */
1648 while (string[0]) {
1649 string++;
1650 if ((*secsize)-- <= 1)
1651 return NULL;
1652 }
1653
1654 /* Skip any zero padding. */
1655 while (!string[0]) {
1656 string++;
1657 if ((*secsize)-- <= 1)
1658 return NULL;
1659 }
1660 return string;
1661 }
1662
1663 static char *get_modinfo(Elf_Shdr *sechdrs,
1664 unsigned int info,
1665 const char *tag)
1666 {
1667 char *p;
1668 unsigned int taglen = strlen(tag);
1669 unsigned long size = sechdrs[info].sh_size;
1670
1671 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1672 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1673 return p + taglen + 1;
1674 }
1675 return NULL;
1676 }
1677
1678 static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1679 unsigned int infoindex)
1680 {
1681 struct module_attribute *attr;
1682 int i;
1683
1684 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1685 if (attr->setup)
1686 attr->setup(mod,
1687 get_modinfo(sechdrs,
1688 infoindex,
1689 attr->attr.name));
1690 }
1691 }
1692
1693 #ifdef CONFIG_KALLSYMS
1694
1695 /* lookup symbol in given range of kernel_symbols */
1696 static const struct kernel_symbol *lookup_symbol(const char *name,
1697 const struct kernel_symbol *start,
1698 const struct kernel_symbol *stop)
1699 {
1700 const struct kernel_symbol *ks = start;
1701 for (; ks < stop; ks++)
1702 if (strcmp(ks->name, name) == 0)
1703 return ks;
1704 return NULL;
1705 }
1706
1707 static int is_exported(const char *name, const struct module *mod)
1708 {
1709 if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
1710 return 1;
1711 else
1712 if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
1713 return 1;
1714 else
1715 return 0;
1716 }
1717
1718 /* As per nm */
1719 static char elf_type(const Elf_Sym *sym,
1720 Elf_Shdr *sechdrs,
1721 const char *secstrings,
1722 struct module *mod)
1723 {
1724 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1725 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1726 return 'v';
1727 else
1728 return 'w';
1729 }
1730 if (sym->st_shndx == SHN_UNDEF)
1731 return 'U';
1732 if (sym->st_shndx == SHN_ABS)
1733 return 'a';
1734 if (sym->st_shndx >= SHN_LORESERVE)
1735 return '?';
1736 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1737 return 't';
1738 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1739 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1740 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1741 return 'r';
1742 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1743 return 'g';
1744 else
1745 return 'd';
1746 }
1747 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1748 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1749 return 's';
1750 else
1751 return 'b';
1752 }
1753 if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
1754 ".debug", strlen(".debug")) == 0)
1755 return 'n';
1756 return '?';
1757 }
1758
1759 static void add_kallsyms(struct module *mod,
1760 Elf_Shdr *sechdrs,
1761 unsigned int symindex,
1762 unsigned int strindex,
1763 const char *secstrings)
1764 {
1765 unsigned int i;
1766
1767 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1768 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1769 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1770
1771 /* Set types up while we still have access to sections. */
1772 for (i = 0; i < mod->num_symtab; i++)
1773 mod->symtab[i].st_info
1774 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1775 }
1776 #else
1777 static inline void add_kallsyms(struct module *mod,
1778 Elf_Shdr *sechdrs,
1779 unsigned int symindex,
1780 unsigned int strindex,
1781 const char *secstrings)
1782 {
1783 }
1784 #endif /* CONFIG_KALLSYMS */
1785
1786 static void *module_alloc_update_bounds(unsigned long size)
1787 {
1788 void *ret = module_alloc(size);
1789
1790 if (ret) {
1791 /* Update module bounds. */
1792 if ((unsigned long)ret < module_addr_min)
1793 module_addr_min = (unsigned long)ret;
1794 if ((unsigned long)ret + size > module_addr_max)
1795 module_addr_max = (unsigned long)ret + size;
1796 }
1797 return ret;
1798 }
1799
1800 /* Allocate and load the module: note that size of section 0 is always
1801 zero, and we rely on this for optional sections. */
1802 static struct module *load_module(void __user *umod,
1803 unsigned long len,
1804 const char __user *uargs)
1805 {
1806 Elf_Ehdr *hdr;
1807 Elf_Shdr *sechdrs;
1808 char *secstrings, *args, *modmagic, *strtab = NULL;
1809 unsigned int i;
1810 unsigned int symindex = 0;
1811 unsigned int strindex = 0;
1812 unsigned int setupindex;
1813 unsigned int exindex;
1814 unsigned int exportindex;
1815 unsigned int modindex;
1816 unsigned int obsparmindex;
1817 unsigned int infoindex;
1818 unsigned int gplindex;
1819 unsigned int crcindex;
1820 unsigned int gplcrcindex;
1821 unsigned int versindex;
1822 unsigned int pcpuindex;
1823 unsigned int gplfutureindex;
1824 unsigned int gplfuturecrcindex;
1825 unsigned int unwindex = 0;
1826 #ifdef CONFIG_UNUSED_SYMBOLS
1827 unsigned int unusedindex;
1828 unsigned int unusedcrcindex;
1829 unsigned int unusedgplindex;
1830 unsigned int unusedgplcrcindex;
1831 #endif
1832 unsigned int markersindex;
1833 unsigned int markersstringsindex;
1834 struct module *mod;
1835 long err = 0;
1836 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1837 struct exception_table_entry *extable;
1838 mm_segment_t old_fs;
1839
1840 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1841 umod, len, uargs);
1842 if (len < sizeof(*hdr))
1843 return ERR_PTR(-ENOEXEC);
1844
1845 /* Suck in entire file: we'll want most of it. */
1846 /* vmalloc barfs on "unusual" numbers. Check here */
1847 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1848 return ERR_PTR(-ENOMEM);
1849 if (copy_from_user(hdr, umod, len) != 0) {
1850 err = -EFAULT;
1851 goto free_hdr;
1852 }
1853
1854 /* Sanity checks against insmoding binaries or wrong arch,
1855 weird elf version */
1856 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
1857 || hdr->e_type != ET_REL
1858 || !elf_check_arch(hdr)
1859 || hdr->e_shentsize != sizeof(*sechdrs)) {
1860 err = -ENOEXEC;
1861 goto free_hdr;
1862 }
1863
1864 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1865 goto truncated;
1866
1867 /* Convenience variables */
1868 sechdrs = (void *)hdr + hdr->e_shoff;
1869 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1870 sechdrs[0].sh_addr = 0;
1871
1872 for (i = 1; i < hdr->e_shnum; i++) {
1873 if (sechdrs[i].sh_type != SHT_NOBITS
1874 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1875 goto truncated;
1876
1877 /* Mark all sections sh_addr with their address in the
1878 temporary image. */
1879 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1880
1881 /* Internal symbols and strings. */
1882 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1883 symindex = i;
1884 strindex = sechdrs[i].sh_link;
1885 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1886 }
1887 #ifndef CONFIG_MODULE_UNLOAD
1888 /* Don't load .exit sections */
1889 if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
1890 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1891 #endif
1892 }
1893
1894 modindex = find_sec(hdr, sechdrs, secstrings,
1895 ".gnu.linkonce.this_module");
1896 if (!modindex) {
1897 printk(KERN_WARNING "No module found in object\n");
1898 err = -ENOEXEC;
1899 goto free_hdr;
1900 }
1901 mod = (void *)sechdrs[modindex].sh_addr;
1902
1903 if (symindex == 0) {
1904 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
1905 mod->name);
1906 err = -ENOEXEC;
1907 goto free_hdr;
1908 }
1909
1910 /* Optional sections */
1911 exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
1912 gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1913 gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1914 crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
1915 gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1916 gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1917 #ifdef CONFIG_UNUSED_SYMBOLS
1918 unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
1919 unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
1920 unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
1921 unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
1922 #endif
1923 setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
1924 exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
1925 obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
1926 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
1927 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
1928 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1929 #ifdef ARCH_UNWIND_SECTION_NAME
1930 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1931 #endif
1932
1933 /* Don't keep modinfo and version sections. */
1934 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1935 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1936 #ifdef CONFIG_KALLSYMS
1937 /* Keep symbol and string tables for decoding later. */
1938 sechdrs[symindex].sh_flags |= SHF_ALLOC;
1939 sechdrs[strindex].sh_flags |= SHF_ALLOC;
1940 #endif
1941 if (unwindex)
1942 sechdrs[unwindex].sh_flags |= SHF_ALLOC;
1943
1944 /* Check module struct version now, before we try to use module. */
1945 if (!check_modstruct_version(sechdrs, versindex, mod)) {
1946 err = -ENOEXEC;
1947 goto free_hdr;
1948 }
1949
1950 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
1951 /* This is allowed: modprobe --force will invalidate it. */
1952 if (!modmagic) {
1953 err = try_to_force_load(mod, "magic");
1954 if (err)
1955 goto free_hdr;
1956 } else if (!same_magic(modmagic, vermagic, versindex)) {
1957 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
1958 mod->name, modmagic, vermagic);
1959 err = -ENOEXEC;
1960 goto free_hdr;
1961 }
1962
1963 /* Now copy in args */
1964 args = strndup_user(uargs, ~0UL >> 1);
1965 if (IS_ERR(args)) {
1966 err = PTR_ERR(args);
1967 goto free_hdr;
1968 }
1969
1970 if (find_module(mod->name)) {
1971 err = -EEXIST;
1972 goto free_mod;
1973 }
1974
1975 mod->state = MODULE_STATE_COMING;
1976
1977 /* Allow arches to frob section contents and sizes. */
1978 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
1979 if (err < 0)
1980 goto free_mod;
1981
1982 if (pcpuindex) {
1983 /* We have a special allocation for this section. */
1984 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1985 sechdrs[pcpuindex].sh_addralign,
1986 mod->name);
1987 if (!percpu) {
1988 err = -ENOMEM;
1989 goto free_mod;
1990 }
1991 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1992 mod->percpu = percpu;
1993 }
1994
1995 /* Determine total sizes, and put offsets in sh_entsize. For now
1996 this is done generically; there doesn't appear to be any
1997 special cases for the architectures. */
1998 layout_sections(mod, hdr, sechdrs, secstrings);
1999
2000 /* Do the allocs. */
2001 ptr = module_alloc_update_bounds(mod->core_size);
2002 if (!ptr) {
2003 err = -ENOMEM;
2004 goto free_percpu;
2005 }
2006 memset(ptr, 0, mod->core_size);
2007 mod->module_core = ptr;
2008
2009 ptr = module_alloc_update_bounds(mod->init_size);
2010 if (!ptr && mod->init_size) {
2011 err = -ENOMEM;
2012 goto free_core;
2013 }
2014 memset(ptr, 0, mod->init_size);
2015 mod->module_init = ptr;
2016
2017 /* Transfer each section which specifies SHF_ALLOC */
2018 DEBUGP("final section addresses:\n");
2019 for (i = 0; i < hdr->e_shnum; i++) {
2020 void *dest;
2021
2022 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2023 continue;
2024
2025 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2026 dest = mod->module_init
2027 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2028 else
2029 dest = mod->module_core + sechdrs[i].sh_entsize;
2030
2031 if (sechdrs[i].sh_type != SHT_NOBITS)
2032 memcpy(dest, (void *)sechdrs[i].sh_addr,
2033 sechdrs[i].sh_size);
2034 /* Update sh_addr to point to copy in image. */
2035 sechdrs[i].sh_addr = (unsigned long)dest;
2036 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2037 }
2038 /* Module has been moved. */
2039 mod = (void *)sechdrs[modindex].sh_addr;
2040
2041 /* Now we've moved module, initialize linked lists, etc. */
2042 module_unload_init(mod);
2043
2044 /* add kobject, so we can reference it. */
2045 err = mod_sysfs_init(mod);
2046 if (err)
2047 goto free_unload;
2048
2049 /* Set up license info based on the info section */
2050 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2051
2052 /*
2053 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2054 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2055 * using GPL-only symbols it needs.
2056 */
2057 if (strcmp(mod->name, "ndiswrapper") == 0)
2058 add_taint(TAINT_PROPRIETARY_MODULE);
2059
2060 /* driverloader was caught wrongly pretending to be under GPL */
2061 if (strcmp(mod->name, "driverloader") == 0)
2062 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2063
2064 /* Set up MODINFO_ATTR fields */
2065 setup_modinfo(mod, sechdrs, infoindex);
2066
2067 /* Fix up syms, so that st_value is a pointer to location. */
2068 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2069 mod);
2070 if (err < 0)
2071 goto cleanup;
2072
2073 /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
2074 mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
2075 mod->syms = (void *)sechdrs[exportindex].sh_addr;
2076 if (crcindex)
2077 mod->crcs = (void *)sechdrs[crcindex].sh_addr;
2078 mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
2079 mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
2080 if (gplcrcindex)
2081 mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
2082 mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
2083 sizeof(*mod->gpl_future_syms);
2084 mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
2085 if (gplfuturecrcindex)
2086 mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
2087
2088 #ifdef CONFIG_UNUSED_SYMBOLS
2089 mod->num_unused_syms = sechdrs[unusedindex].sh_size /
2090 sizeof(*mod->unused_syms);
2091 mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
2092 sizeof(*mod->unused_gpl_syms);
2093 mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
2094 if (unusedcrcindex)
2095 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
2096 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
2097 if (unusedgplcrcindex)
2098 mod->unused_gpl_crcs
2099 = (void *)sechdrs[unusedgplcrcindex].sh_addr;
2100 #endif
2101
2102 #ifdef CONFIG_MODVERSIONS
2103 if ((mod->num_syms && !crcindex)
2104 || (mod->num_gpl_syms && !gplcrcindex)
2105 || (mod->num_gpl_future_syms && !gplfuturecrcindex)
2106 #ifdef CONFIG_UNUSED_SYMBOLS
2107 || (mod->num_unused_syms && !unusedcrcindex)
2108 || (mod->num_unused_gpl_syms && !unusedgplcrcindex)
2109 #endif
2110 ) {
2111 printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name);
2112 err = try_to_force_load(mod, "nocrc");
2113 if (err)
2114 goto cleanup;
2115 }
2116 #endif
2117 markersindex = find_sec(hdr, sechdrs, secstrings, "__markers");
2118 markersstringsindex = find_sec(hdr, sechdrs, secstrings,
2119 "__markers_strings");
2120
2121 /* Now do relocations. */
2122 for (i = 1; i < hdr->e_shnum; i++) {
2123 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2124 unsigned int info = sechdrs[i].sh_info;
2125
2126 /* Not a valid relocation section? */
2127 if (info >= hdr->e_shnum)
2128 continue;
2129
2130 /* Don't bother with non-allocated sections */
2131 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2132 continue;
2133
2134 if (sechdrs[i].sh_type == SHT_REL)
2135 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2136 else if (sechdrs[i].sh_type == SHT_RELA)
2137 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2138 mod);
2139 if (err < 0)
2140 goto cleanup;
2141 }
2142 #ifdef CONFIG_MARKERS
2143 mod->markers = (void *)sechdrs[markersindex].sh_addr;
2144 mod->num_markers =
2145 sechdrs[markersindex].sh_size / sizeof(*mod->markers);
2146 #endif
2147
2148 /* Find duplicate symbols */
2149 err = verify_export_symbols(mod);
2150
2151 if (err < 0)
2152 goto cleanup;
2153
2154 /* Set up and sort exception table */
2155 mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
2156 mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
2157 sort_extable(extable, extable + mod->num_exentries);
2158
2159 /* Finally, copy percpu area over. */
2160 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
2161 sechdrs[pcpuindex].sh_size);
2162
2163 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
2164
2165 #ifdef CONFIG_MARKERS
2166 if (!mod->taints)
2167 marker_update_probe_range(mod->markers,
2168 mod->markers + mod->num_markers);
2169 #endif
2170 err = module_finalize(hdr, sechdrs, mod);
2171 if (err < 0)
2172 goto cleanup;
2173
2174 /* flush the icache in correct context */
2175 old_fs = get_fs();
2176 set_fs(KERNEL_DS);
2177
2178 /*
2179 * Flush the instruction cache, since we've played with text.
2180 * Do it before processing of module parameters, so the module
2181 * can provide parameter accessor functions of its own.
2182 */
2183 if (mod->module_init)
2184 flush_icache_range((unsigned long)mod->module_init,
2185 (unsigned long)mod->module_init
2186 + mod->init_size);
2187 flush_icache_range((unsigned long)mod->module_core,
2188 (unsigned long)mod->module_core + mod->core_size);
2189
2190 set_fs(old_fs);
2191
2192 mod->args = args;
2193 if (obsparmindex)
2194 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2195 mod->name);
2196
2197 /* Now sew it into the lists so we can get lockdep and oops
2198 * info during argument parsing. Noone should access us, since
2199 * strong_try_module_get() will fail. */
2200 stop_machine(__link_module, mod, NULL);
2201
2202 /* Size of section 0 is 0, so this works well if no params */
2203 err = parse_args(mod->name, mod->args,
2204 (struct kernel_param *)
2205 sechdrs[setupindex].sh_addr,
2206 sechdrs[setupindex].sh_size
2207 / sizeof(struct kernel_param),
2208 NULL);
2209 if (err < 0)
2210 goto unlink;
2211
2212 err = mod_sysfs_setup(mod,
2213 (struct kernel_param *)
2214 sechdrs[setupindex].sh_addr,
2215 sechdrs[setupindex].sh_size
2216 / sizeof(struct kernel_param));
2217 if (err < 0)
2218 goto unlink;
2219 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2220 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2221
2222 /* Size of section 0 is 0, so this works well if no unwind info. */
2223 mod->unwind_info = unwind_add_table(mod,
2224 (void *)sechdrs[unwindex].sh_addr,
2225 sechdrs[unwindex].sh_size);
2226
2227 /* Get rid of temporary copy */
2228 vfree(hdr);
2229
2230 /* Done! */
2231 return mod;
2232
2233 unlink:
2234 stop_machine(__unlink_module, mod, NULL);
2235 module_arch_cleanup(mod);
2236 cleanup:
2237 kobject_del(&mod->mkobj.kobj);
2238 kobject_put(&mod->mkobj.kobj);
2239 free_unload:
2240 module_unload_free(mod);
2241 module_free(mod, mod->module_init);
2242 free_core:
2243 module_free(mod, mod->module_core);
2244 free_percpu:
2245 if (percpu)
2246 percpu_modfree(percpu);
2247 free_mod:
2248 kfree(args);
2249 free_hdr:
2250 vfree(hdr);
2251 return ERR_PTR(err);
2252
2253 truncated:
2254 printk(KERN_ERR "Module len %lu truncated\n", len);
2255 err = -ENOEXEC;
2256 goto free_hdr;
2257 }
2258
2259 /* This is where the real work happens */
2260 asmlinkage long
2261 sys_init_module(void __user *umod,
2262 unsigned long len,
2263 const char __user *uargs)
2264 {
2265 struct module *mod;
2266 int ret = 0;
2267
2268 /* Must have permission */
2269 if (!capable(CAP_SYS_MODULE))
2270 return -EPERM;
2271
2272 /* Only one module load at a time, please */
2273 if (mutex_lock_interruptible(&module_mutex) != 0)
2274 return -EINTR;
2275
2276 /* Do all the hard work */
2277 mod = load_module(umod, len, uargs);
2278 if (IS_ERR(mod)) {
2279 mutex_unlock(&module_mutex);
2280 return PTR_ERR(mod);
2281 }
2282
2283 /* Drop lock so they can recurse */
2284 mutex_unlock(&module_mutex);
2285
2286 blocking_notifier_call_chain(&module_notify_list,
2287 MODULE_STATE_COMING, mod);
2288
2289 /* Start the module */
2290 if (mod->init != NULL)
2291 ret = mod->init();
2292 if (ret < 0) {
2293 /* Init routine failed: abort. Try to protect us from
2294 buggy refcounters. */
2295 mod->state = MODULE_STATE_GOING;
2296 synchronize_sched();
2297 module_put(mod);
2298 blocking_notifier_call_chain(&module_notify_list,
2299 MODULE_STATE_GOING, mod);
2300 mutex_lock(&module_mutex);
2301 free_module(mod);
2302 mutex_unlock(&module_mutex);
2303 wake_up(&module_wq);
2304 return ret;
2305 }
2306 if (ret > 0) {
2307 printk(KERN_WARNING "%s: '%s'->init suspiciously returned %d, "
2308 "it should follow 0/-E convention\n"
2309 KERN_WARNING "%s: loading module anyway...\n",
2310 __func__, mod->name, ret,
2311 __func__);
2312 dump_stack();
2313 }
2314
2315 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2316 mod->state = MODULE_STATE_LIVE;
2317 wake_up(&module_wq);
2318
2319 mutex_lock(&module_mutex);
2320 /* Drop initial reference. */
2321 module_put(mod);
2322 unwind_remove_table(mod->unwind_info, 1);
2323 module_free(mod, mod->module_init);
2324 mod->module_init = NULL;
2325 mod->init_size = 0;
2326 mod->init_text_size = 0;
2327 mutex_unlock(&module_mutex);
2328
2329 return 0;
2330 }
2331
2332 static inline int within(unsigned long addr, void *start, unsigned long size)
2333 {
2334 return ((void *)addr >= start && (void *)addr < start + size);
2335 }
2336
2337 #ifdef CONFIG_KALLSYMS
2338 /*
2339 * This ignores the intensely annoying "mapping symbols" found
2340 * in ARM ELF files: $a, $t and $d.
2341 */
2342 static inline int is_arm_mapping_symbol(const char *str)
2343 {
2344 return str[0] == '$' && strchr("atd", str[1])
2345 && (str[2] == '\0' || str[2] == '.');
2346 }
2347
2348 static const char *get_ksymbol(struct module *mod,
2349 unsigned long addr,
2350 unsigned long *size,
2351 unsigned long *offset)
2352 {
2353 unsigned int i, best = 0;
2354 unsigned long nextval;
2355
2356 /* At worse, next value is at end of module */
2357 if (within(addr, mod->module_init, mod->init_size))
2358 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2359 else
2360 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2361
2362 /* Scan for closest preceeding symbol, and next symbol. (ELF
2363 starts real symbols at 1). */
2364 for (i = 1; i < mod->num_symtab; i++) {
2365 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2366 continue;
2367
2368 /* We ignore unnamed symbols: they're uninformative
2369 * and inserted at a whim. */
2370 if (mod->symtab[i].st_value <= addr
2371 && mod->symtab[i].st_value > mod->symtab[best].st_value
2372 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2373 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2374 best = i;
2375 if (mod->symtab[i].st_value > addr
2376 && mod->symtab[i].st_value < nextval
2377 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2378 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2379 nextval = mod->symtab[i].st_value;
2380 }
2381
2382 if (!best)
2383 return NULL;
2384
2385 if (size)
2386 *size = nextval - mod->symtab[best].st_value;
2387 if (offset)
2388 *offset = addr - mod->symtab[best].st_value;
2389 return mod->strtab + mod->symtab[best].st_name;
2390 }
2391
2392 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2393 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2394 const char *module_address_lookup(unsigned long addr,
2395 unsigned long *size,
2396 unsigned long *offset,
2397 char **modname,
2398 char *namebuf)
2399 {
2400 struct module *mod;
2401 const char *ret = NULL;
2402
2403 preempt_disable();
2404 list_for_each_entry(mod, &modules, list) {
2405 if (within(addr, mod->module_init, mod->init_size)
2406 || within(addr, mod->module_core, mod->core_size)) {
2407 if (modname)
2408 *modname = mod->name;
2409 ret = get_ksymbol(mod, addr, size, offset);
2410 break;
2411 }
2412 }
2413 /* Make a copy in here where it's safe */
2414 if (ret) {
2415 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2416 ret = namebuf;
2417 }
2418 preempt_enable();
2419 return ret;
2420 }
2421
2422 int lookup_module_symbol_name(unsigned long addr, char *symname)
2423 {
2424 struct module *mod;
2425
2426 preempt_disable();
2427 list_for_each_entry(mod, &modules, list) {
2428 if (within(addr, mod->module_init, mod->init_size) ||
2429 within(addr, mod->module_core, mod->core_size)) {
2430 const char *sym;
2431
2432 sym = get_ksymbol(mod, addr, NULL, NULL);
2433 if (!sym)
2434 goto out;
2435 strlcpy(symname, sym, KSYM_NAME_LEN);
2436 preempt_enable();
2437 return 0;
2438 }
2439 }
2440 out:
2441 preempt_enable();
2442 return -ERANGE;
2443 }
2444
2445 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2446 unsigned long *offset, char *modname, char *name)
2447 {
2448 struct module *mod;
2449
2450 preempt_disable();
2451 list_for_each_entry(mod, &modules, list) {
2452 if (within(addr, mod->module_init, mod->init_size) ||
2453 within(addr, mod->module_core, mod->core_size)) {
2454 const char *sym;
2455
2456 sym = get_ksymbol(mod, addr, size, offset);
2457 if (!sym)
2458 goto out;
2459 if (modname)
2460 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2461 if (name)
2462 strlcpy(name, sym, KSYM_NAME_LEN);
2463 preempt_enable();
2464 return 0;
2465 }
2466 }
2467 out:
2468 preempt_enable();
2469 return -ERANGE;
2470 }
2471
2472 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2473 char *name, char *module_name, int *exported)
2474 {
2475 struct module *mod;
2476
2477 preempt_disable();
2478 list_for_each_entry(mod, &modules, list) {
2479 if (symnum < mod->num_symtab) {
2480 *value = mod->symtab[symnum].st_value;
2481 *type = mod->symtab[symnum].st_info;
2482 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2483 KSYM_NAME_LEN);
2484 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2485 *exported = is_exported(name, mod);
2486 preempt_enable();
2487 return 0;
2488 }
2489 symnum -= mod->num_symtab;
2490 }
2491 preempt_enable();
2492 return -ERANGE;
2493 }
2494
2495 static unsigned long mod_find_symname(struct module *mod, const char *name)
2496 {
2497 unsigned int i;
2498
2499 for (i = 0; i < mod->num_symtab; i++)
2500 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2501 mod->symtab[i].st_info != 'U')
2502 return mod->symtab[i].st_value;
2503 return 0;
2504 }
2505
2506 /* Look for this name: can be of form module:name. */
2507 unsigned long module_kallsyms_lookup_name(const char *name)
2508 {
2509 struct module *mod;
2510 char *colon;
2511 unsigned long ret = 0;
2512
2513 /* Don't lock: we're in enough trouble already. */
2514 preempt_disable();
2515 if ((colon = strchr(name, ':')) != NULL) {
2516 *colon = '\0';
2517 if ((mod = find_module(name)) != NULL)
2518 ret = mod_find_symname(mod, colon+1);
2519 *colon = ':';
2520 } else {
2521 list_for_each_entry(mod, &modules, list)
2522 if ((ret = mod_find_symname(mod, name)) != 0)
2523 break;
2524 }
2525 preempt_enable();
2526 return ret;
2527 }
2528 #endif /* CONFIG_KALLSYMS */
2529
2530 /* Called by the /proc file system to return a list of modules. */
2531 static void *m_start(struct seq_file *m, loff_t *pos)
2532 {
2533 mutex_lock(&module_mutex);
2534 return seq_list_start(&modules, *pos);
2535 }
2536
2537 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2538 {
2539 return seq_list_next(p, &modules, pos);
2540 }
2541
2542 static void m_stop(struct seq_file *m, void *p)
2543 {
2544 mutex_unlock(&module_mutex);
2545 }
2546
2547 static char *module_flags(struct module *mod, char *buf)
2548 {
2549 int bx = 0;
2550
2551 if (mod->taints ||
2552 mod->state == MODULE_STATE_GOING ||
2553 mod->state == MODULE_STATE_COMING) {
2554 buf[bx++] = '(';
2555 if (mod->taints & TAINT_PROPRIETARY_MODULE)
2556 buf[bx++] = 'P';
2557 if (mod->taints & TAINT_FORCED_MODULE)
2558 buf[bx++] = 'F';
2559 /*
2560 * TAINT_FORCED_RMMOD: could be added.
2561 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2562 * apply to modules.
2563 */
2564
2565 /* Show a - for module-is-being-unloaded */
2566 if (mod->state == MODULE_STATE_GOING)
2567 buf[bx++] = '-';
2568 /* Show a + for module-is-being-loaded */
2569 if (mod->state == MODULE_STATE_COMING)
2570 buf[bx++] = '+';
2571 buf[bx++] = ')';
2572 }
2573 buf[bx] = '\0';
2574
2575 return buf;
2576 }
2577
2578 static int m_show(struct seq_file *m, void *p)
2579 {
2580 struct module *mod = list_entry(p, struct module, list);
2581 char buf[8];
2582
2583 seq_printf(m, "%s %u",
2584 mod->name, mod->init_size + mod->core_size);
2585 print_unload_info(m, mod);
2586
2587 /* Informative for users. */
2588 seq_printf(m, " %s",
2589 mod->state == MODULE_STATE_GOING ? "Unloading":
2590 mod->state == MODULE_STATE_COMING ? "Loading":
2591 "Live");
2592 /* Used by oprofile and other similar tools. */
2593 seq_printf(m, " 0x%p", mod->module_core);
2594
2595 /* Taints info */
2596 if (mod->taints)
2597 seq_printf(m, " %s", module_flags(mod, buf));
2598
2599 seq_printf(m, "\n");
2600 return 0;
2601 }
2602
2603 /* Format: modulename size refcount deps address
2604
2605 Where refcount is a number or -, and deps is a comma-separated list
2606 of depends or -.
2607 */
2608 const struct seq_operations modules_op = {
2609 .start = m_start,
2610 .next = m_next,
2611 .stop = m_stop,
2612 .show = m_show
2613 };
2614
2615 /* Given an address, look for it in the module exception tables. */
2616 const struct exception_table_entry *search_module_extables(unsigned long addr)
2617 {
2618 const struct exception_table_entry *e = NULL;
2619 struct module *mod;
2620
2621 preempt_disable();
2622 list_for_each_entry(mod, &modules, list) {
2623 if (mod->num_exentries == 0)
2624 continue;
2625
2626 e = search_extable(mod->extable,
2627 mod->extable + mod->num_exentries - 1,
2628 addr);
2629 if (e)
2630 break;
2631 }
2632 preempt_enable();
2633
2634 /* Now, if we found one, we are running inside it now, hence
2635 we cannot unload the module, hence no refcnt needed. */
2636 return e;
2637 }
2638
2639 /*
2640 * Is this a valid module address?
2641 */
2642 int is_module_address(unsigned long addr)
2643 {
2644 struct module *mod;
2645
2646 preempt_disable();
2647
2648 list_for_each_entry(mod, &modules, list) {
2649 if (within(addr, mod->module_core, mod->core_size)) {
2650 preempt_enable();
2651 return 1;
2652 }
2653 }
2654
2655 preempt_enable();
2656
2657 return 0;
2658 }
2659
2660
2661 /* Is this a valid kernel address? */
2662 struct module *__module_text_address(unsigned long addr)
2663 {
2664 struct module *mod;
2665
2666 if (addr < module_addr_min || addr > module_addr_max)
2667 return NULL;
2668
2669 list_for_each_entry(mod, &modules, list)
2670 if (within(addr, mod->module_init, mod->init_text_size)
2671 || within(addr, mod->module_core, mod->core_text_size))
2672 return mod;
2673 return NULL;
2674 }
2675
2676 struct module *module_text_address(unsigned long addr)
2677 {
2678 struct module *mod;
2679
2680 preempt_disable();
2681 mod = __module_text_address(addr);
2682 preempt_enable();
2683
2684 return mod;
2685 }
2686
2687 /* Don't grab lock, we're oopsing. */
2688 void print_modules(void)
2689 {
2690 struct module *mod;
2691 char buf[8];
2692
2693 printk("Modules linked in:");
2694 list_for_each_entry(mod, &modules, list)
2695 printk(" %s%s", mod->name, module_flags(mod, buf));
2696 if (last_unloaded_module[0])
2697 printk(" [last unloaded: %s]", last_unloaded_module);
2698 printk("\n");
2699 }
2700
2701 #ifdef CONFIG_MODVERSIONS
2702 /* Generate the signature for struct module here, too, for modversions. */
2703 void struct_module(struct module *mod) { return; }
2704 EXPORT_SYMBOL(struct_module);
2705 #endif
2706
2707 #ifdef CONFIG_MARKERS
2708 void module_update_markers(void)
2709 {
2710 struct module *mod;
2711
2712 mutex_lock(&module_mutex);
2713 list_for_each_entry(mod, &modules, list)
2714 if (!mod->taints)
2715 marker_update_probe_range(mod->markers,
2716 mod->markers + mod->num_markers);
2717 mutex_unlock(&module_mutex);
2718 }
2719 #endif
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree