projects/linux·blob v2.6.31-rc3 · refs

3002 lines · 76.5 KiB

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/ftrace_event.h>
22#include <linux/init.h>
23#include <linux/kallsyms.h>
24#include <linux/fs.h>
25#include <linux/sysfs.h>
26#include <linux/kernel.h>
27#include <linux/slab.h>
28#include <linux/vmalloc.h>
29#include <linux/elf.h>
30#include <linux/proc_fs.h>
31#include <linux/seq_file.h>
32#include <linux/syscalls.h>
33#include <linux/fcntl.h>
34#include <linux/rcupdate.h>
35#include <linux/capability.h>
36#include <linux/cpu.h>
37#include <linux/moduleparam.h>
38#include <linux/errno.h>
39#include <linux/err.h>
40#include <linux/vermagic.h>
41#include <linux/notifier.h>
42#include <linux/sched.h>
43#include <linux/stop_machine.h>
44#include <linux/device.h>
45#include <linux/string.h>
46#include <linux/mutex.h>
47#include <linux/rculist.h>
48#include <asm/uaccess.h>
49#include <asm/cacheflush.h>
50#include <linux/license.h>
51#include <asm/sections.h>
52#include <linux/tracepoint.h>
53#include <linux/ftrace.h>
54#include <linux/async.h>
55#include <linux/percpu.h>
56#include <linux/kmemleak.h>
57
58#if 0
59#define DEBUGP printk
60#else
61#define DEBUGP(fmt , a...)
62#endif
63
64#ifndef ARCH_SHF_SMALL
65#define ARCH_SHF_SMALL 0
66#endif
67
68/* If this is set, the section belongs in the init part of the module */
69#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
70
71/* List of modules, protected by module_mutex or preempt_disable
72 * (delete uses stop_machine/add uses RCU list operations). */
73DEFINE_MUTEX(module_mutex);
74EXPORT_SYMBOL_GPL(module_mutex);
75static LIST_HEAD(modules);
76
77/* Block module loading/unloading? */
78int modules_disabled = 0;
79
80/* Waiting for a module to finish initializing? */
81static DECLARE_WAIT_QUEUE_HEAD(module_wq);
82
83static BLOCKING_NOTIFIER_HEAD(module_notify_list);
84
85/* Bounds of module allocation, for speeding __module_address */
86static unsigned long module_addr_min = -1UL, module_addr_max = 0;
87
88int register_module_notifier(struct notifier_block * nb)
89{
90 return blocking_notifier_chain_register(&module_notify_list, nb);
91}
92EXPORT_SYMBOL(register_module_notifier);
93
94int unregister_module_notifier(struct notifier_block * nb)
95{
96 return blocking_notifier_chain_unregister(&module_notify_list, nb);
97}
98EXPORT_SYMBOL(unregister_module_notifier);
99
100/* We require a truly strong try_module_get(): 0 means failure due to
101 ongoing or failed initialization etc. */
102static inline int strong_try_module_get(struct module *mod)
103{
104 if (mod && mod->state == MODULE_STATE_COMING)
105 return -EBUSY;
106 if (try_module_get(mod))
107 return 0;
108 else
109 return -ENOENT;
110}
111
112static inline void add_taint_module(struct module *mod, unsigned flag)
113{
114 add_taint(flag);
115 mod->taints |= (1U << flag);
116}
117
118/*
119 * A thread that wants to hold a reference to a module only while it
120 * is running can call this to safely exit. nfsd and lockd use this.
121 */
122void __module_put_and_exit(struct module *mod, long code)
123{
124 module_put(mod);
125 do_exit(code);
126}
127EXPORT_SYMBOL(__module_put_and_exit);
128
129/* Find a module section: 0 means not found. */
130static unsigned int find_sec(Elf_Ehdr *hdr,
131 Elf_Shdr *sechdrs,
132 const char *secstrings,
133 const char *name)
134{
135 unsigned int i;
136
137 for (i = 1; i < hdr->e_shnum; i++)
138 /* Alloc bit cleared means "ignore it." */
139 if ((sechdrs[i].sh_flags & SHF_ALLOC)
140 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
141 return i;
142 return 0;
143}
144
145/* Find a module section, or NULL. */
146static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
147 const char *secstrings, const char *name)
148{
149 /* Section 0 has sh_addr 0. */
150 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
151}
152
153/* Find a module section, or NULL. Fill in number of "objects" in section. */
154static void *section_objs(Elf_Ehdr *hdr,
155 Elf_Shdr *sechdrs,
156 const char *secstrings,
157 const char *name,
158 size_t object_size,
159 unsigned int *num)
160{
161 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
162
163 /* Section 0 has sh_addr 0 and sh_size 0. */
164 *num = sechdrs[sec].sh_size / object_size;
165 return (void *)sechdrs[sec].sh_addr;
166}
167
168/* Provided by the linker */
169extern const struct kernel_symbol __start___ksymtab[];
170extern const struct kernel_symbol __stop___ksymtab[];
171extern const struct kernel_symbol __start___ksymtab_gpl[];
172extern const struct kernel_symbol __stop___ksymtab_gpl[];
173extern const struct kernel_symbol __start___ksymtab_gpl_future[];
174extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
175extern const struct kernel_symbol __start___ksymtab_gpl_future[];
176extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
177extern const unsigned long __start___kcrctab[];
178extern const unsigned long __start___kcrctab_gpl[];
179extern const unsigned long __start___kcrctab_gpl_future[];
180#ifdef CONFIG_UNUSED_SYMBOLS
181extern const struct kernel_symbol __start___ksymtab_unused[];
182extern const struct kernel_symbol __stop___ksymtab_unused[];
183extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
184extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
185extern const unsigned long __start___kcrctab_unused[];
186extern const unsigned long __start___kcrctab_unused_gpl[];
187#endif
188
189#ifndef CONFIG_MODVERSIONS
190#define symversion(base, idx) NULL
191#else
192#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
193#endif
194
195static bool each_symbol_in_section(const struct symsearch *arr,
196 unsigned int arrsize,
197 struct module *owner,
198 bool (*fn)(const struct symsearch *syms,
199 struct module *owner,
200 unsigned int symnum, void *data),
201 void *data)
202{
203 unsigned int i, j;
204
205 for (j = 0; j < arrsize; j++) {
206 for (i = 0; i < arr[j].stop - arr[j].start; i++)
207 if (fn(&arr[j], owner, i, data))
208 return true;
209 }
210
211 return false;
212}
213
214/* Returns true as soon as fn returns true, otherwise false. */
215bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
216 unsigned int symnum, void *data), void *data)
217{
218 struct module *mod;
219 const struct symsearch arr[] = {
220 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
221 NOT_GPL_ONLY, false },
222 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
223 __start___kcrctab_gpl,
224 GPL_ONLY, false },
225 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
226 __start___kcrctab_gpl_future,
227 WILL_BE_GPL_ONLY, false },
228#ifdef CONFIG_UNUSED_SYMBOLS
229 { __start___ksymtab_unused, __stop___ksymtab_unused,
230 __start___kcrctab_unused,
231 NOT_GPL_ONLY, true },
232 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
233 __start___kcrctab_unused_gpl,
234 GPL_ONLY, true },
235#endif
236 };
237
238 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
239 return true;
240
241 list_for_each_entry_rcu(mod, &modules, list) {
242 struct symsearch arr[] = {
243 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
244 NOT_GPL_ONLY, false },
245 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
246 mod->gpl_crcs,
247 GPL_ONLY, false },
248 { mod->gpl_future_syms,
249 mod->gpl_future_syms + mod->num_gpl_future_syms,
250 mod->gpl_future_crcs,
251 WILL_BE_GPL_ONLY, false },
252#ifdef CONFIG_UNUSED_SYMBOLS
253 { mod->unused_syms,
254 mod->unused_syms + mod->num_unused_syms,
255 mod->unused_crcs,
256 NOT_GPL_ONLY, true },
257 { mod->unused_gpl_syms,
258 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
259 mod->unused_gpl_crcs,
260 GPL_ONLY, true },
261#endif
262 };
263
264 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
265 return true;
266 }
267 return false;
268}
269EXPORT_SYMBOL_GPL(each_symbol);
270
271struct find_symbol_arg {
272 /* Input */
273 const char *name;
274 bool gplok;
275 bool warn;
276
277 /* Output */
278 struct module *owner;
279 const unsigned long *crc;
280 const struct kernel_symbol *sym;
281};
282
283static bool find_symbol_in_section(const struct symsearch *syms,
284 struct module *owner,
285 unsigned int symnum, void *data)
286{
287 struct find_symbol_arg *fsa = data;
288
289 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
290 return false;
291
292 if (!fsa->gplok) {
293 if (syms->licence == GPL_ONLY)
294 return false;
295 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
296 printk(KERN_WARNING "Symbol %s is being used "
297 "by a non-GPL module, which will not "
298 "be allowed in the future\n", fsa->name);
299 printk(KERN_WARNING "Please see the file "
300 "Documentation/feature-removal-schedule.txt "
301 "in the kernel source tree for more details.\n");
302 }
303 }
304
305#ifdef CONFIG_UNUSED_SYMBOLS
306 if (syms->unused && fsa->warn) {
307 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
308 "however this module is using it.\n", fsa->name);
309 printk(KERN_WARNING
310 "This symbol will go away in the future.\n");
311 printk(KERN_WARNING
312 "Please evalute if this is the right api to use and if "
313 "it really is, submit a report the linux kernel "
314 "mailinglist together with submitting your code for "
315 "inclusion.\n");
316 }
317#endif
318
319 fsa->owner = owner;
320 fsa->crc = symversion(syms->crcs, symnum);
321 fsa->sym = &syms->start[symnum];
322 return true;
323}
324
325/* Find a symbol and return it, along with, (optional) crc and
326 * (optional) module which owns it */
327const struct kernel_symbol *find_symbol(const char *name,
328 struct module **owner,
329 const unsigned long **crc,
330 bool gplok,
331 bool warn)
332{
333 struct find_symbol_arg fsa;
334
335 fsa.name = name;
336 fsa.gplok = gplok;
337 fsa.warn = warn;
338
339 if (each_symbol(find_symbol_in_section, &fsa)) {
340 if (owner)
341 *owner = fsa.owner;
342 if (crc)
343 *crc = fsa.crc;
344 return fsa.sym;
345 }
346
347 DEBUGP("Failed to find symbol %s\n", name);
348 return NULL;
349}
350EXPORT_SYMBOL_GPL(find_symbol);
351
352/* Search for module by name: must hold module_mutex. */
353struct module *find_module(const char *name)
354{
355 struct module *mod;
356
357 list_for_each_entry(mod, &modules, list) {
358 if (strcmp(mod->name, name) == 0)
359 return mod;
360 }
361 return NULL;
362}
363EXPORT_SYMBOL_GPL(find_module);
364
365#ifdef CONFIG_SMP
366
367#ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA
368
369static void *percpu_modalloc(unsigned long size, unsigned long align,
370 const char *name)
371{
372 void *ptr;
373
374 if (align > PAGE_SIZE) {
375 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
376 name, align, PAGE_SIZE);
377 align = PAGE_SIZE;
378 }
379
380 ptr = __alloc_reserved_percpu(size, align);
381 if (!ptr)
382 printk(KERN_WARNING
383 "Could not allocate %lu bytes percpu data\n", size);
384 return ptr;
385}
386
387static void percpu_modfree(void *freeme)
388{
389 free_percpu(freeme);
390}
391
392#else /* ... !CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
393
394/* Number of blocks used and allocated. */
395static unsigned int pcpu_num_used, pcpu_num_allocated;
396/* Size of each block. -ve means used. */
397static int *pcpu_size;
398
399static int split_block(unsigned int i, unsigned short size)
400{
401 /* Reallocation required? */
402 if (pcpu_num_used + 1 > pcpu_num_allocated) {
403 int *new;
404
405 new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2,
406 GFP_KERNEL);
407 if (!new)
408 return 0;
409
410 pcpu_num_allocated *= 2;
411 pcpu_size = new;
412 }
413
414 /* Insert a new subblock */
415 memmove(&pcpu_size[i+1], &pcpu_size[i],
416 sizeof(pcpu_size[0]) * (pcpu_num_used - i));
417 pcpu_num_used++;
418
419 pcpu_size[i+1] -= size;
420 pcpu_size[i] = size;
421 return 1;
422}
423
424static inline unsigned int block_size(int val)
425{
426 if (val < 0)
427 return -val;
428 return val;
429}
430
431static void *percpu_modalloc(unsigned long size, unsigned long align,
432 const char *name)
433{
434 unsigned long extra;
435 unsigned int i;
436 void *ptr;
437 int cpu;
438
439 if (align > PAGE_SIZE) {
440 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
441 name, align, PAGE_SIZE);
442 align = PAGE_SIZE;
443 }
444
445 ptr = __per_cpu_start;
446 for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
447 /* Extra for alignment requirement. */
448 extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
449 BUG_ON(i == 0 && extra != 0);
450
451 if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
452 continue;
453
454 /* Transfer extra to previous block. */
455 if (pcpu_size[i-1] < 0)
456 pcpu_size[i-1] -= extra;
457 else
458 pcpu_size[i-1] += extra;
459 pcpu_size[i] -= extra;
460 ptr += extra;
461
462 /* Split block if warranted */
463 if (pcpu_size[i] - size > sizeof(unsigned long))
464 if (!split_block(i, size))
465 return NULL;
466
467 /* add the per-cpu scanning areas */
468 for_each_possible_cpu(cpu)
469 kmemleak_alloc(ptr + per_cpu_offset(cpu), size, 0,
470 GFP_KERNEL);
471
472 /* Mark allocated */
473 pcpu_size[i] = -pcpu_size[i];
474 return ptr;
475 }
476
477 printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
478 size);
479 return NULL;
480}
481
482static void percpu_modfree(void *freeme)
483{
484 unsigned int i;
485 void *ptr = __per_cpu_start + block_size(pcpu_size[0]);
486 int cpu;
487
488 /* First entry is core kernel percpu data. */
489 for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
490 if (ptr == freeme) {
491 pcpu_size[i] = -pcpu_size[i];
492 goto free;
493 }
494 }
495 BUG();
496
497 free:
498 /* remove the per-cpu scanning areas */
499 for_each_possible_cpu(cpu)
500 kmemleak_free(freeme + per_cpu_offset(cpu));
501
502 /* Merge with previous? */
503 if (pcpu_size[i-1] >= 0) {
504 pcpu_size[i-1] += pcpu_size[i];
505 pcpu_num_used--;
506 memmove(&pcpu_size[i], &pcpu_size[i+1],
507 (pcpu_num_used - i) * sizeof(pcpu_size[0]));
508 i--;
509 }
510 /* Merge with next? */
511 if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
512 pcpu_size[i] += pcpu_size[i+1];
513 pcpu_num_used--;
514 memmove(&pcpu_size[i+1], &pcpu_size[i+2],
515 (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
516 }
517}
518
519static int percpu_modinit(void)
520{
521 pcpu_num_used = 2;
522 pcpu_num_allocated = 2;
523 pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
524 GFP_KERNEL);
525 /* Static in-kernel percpu data (used). */
526 pcpu_size[0] = -(__per_cpu_end-__per_cpu_start);
527 /* Free room. */
528 pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
529 if (pcpu_size[1] < 0) {
530 printk(KERN_ERR "No per-cpu room for modules.\n");
531 pcpu_num_used = 1;
532 }
533
534 return 0;
535}
536__initcall(percpu_modinit);
537
538#endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
539
540static unsigned int find_pcpusec(Elf_Ehdr *hdr,
541 Elf_Shdr *sechdrs,
542 const char *secstrings)
543{
544 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
545}
546
547static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
548{
549 int cpu;
550
551 for_each_possible_cpu(cpu)
552 memcpy(pcpudest + per_cpu_offset(cpu), from, size);
553}
554
555#else /* ... !CONFIG_SMP */
556
557static inline void *percpu_modalloc(unsigned long size, unsigned long align,
558 const char *name)
559{
560 return NULL;
561}
562static inline void percpu_modfree(void *pcpuptr)
563{
564 BUG();
565}
566static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
567 Elf_Shdr *sechdrs,
568 const char *secstrings)
569{
570 return 0;
571}
572static inline void percpu_modcopy(void *pcpudst, const void *src,
573 unsigned long size)
574{
575 /* pcpusec should be 0, and size of that section should be 0. */
576 BUG_ON(size != 0);
577}
578
579#endif /* CONFIG_SMP */
580
581#define MODINFO_ATTR(field) \
582static void setup_modinfo_##field(struct module *mod, const char *s) \
583{ \
584 mod->field = kstrdup(s, GFP_KERNEL); \
585} \
586static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
587 struct module *mod, char *buffer) \
588{ \
589 return sprintf(buffer, "%s\n", mod->field); \
590} \
591static int modinfo_##field##_exists(struct module *mod) \
592{ \
593 return mod->field != NULL; \
594} \
595static void free_modinfo_##field(struct module *mod) \
596{ \
597 kfree(mod->field); \
598 mod->field = NULL; \
599} \
600static struct module_attribute modinfo_##field = { \
601 .attr = { .name = __stringify(field), .mode = 0444 }, \
602 .show = show_modinfo_##field, \
603 .setup = setup_modinfo_##field, \
604 .test = modinfo_##field##_exists, \
605 .free = free_modinfo_##field, \
606};
607
608MODINFO_ATTR(version);
609MODINFO_ATTR(srcversion);
610
611static char last_unloaded_module[MODULE_NAME_LEN+1];
612
613#ifdef CONFIG_MODULE_UNLOAD
614/* Init the unload section of the module. */
615static void module_unload_init(struct module *mod)
616{
617 int cpu;
618
619 INIT_LIST_HEAD(&mod->modules_which_use_me);
620 for_each_possible_cpu(cpu)
621 local_set(__module_ref_addr(mod, cpu), 0);
622 /* Hold reference count during initialization. */
623 local_set(__module_ref_addr(mod, raw_smp_processor_id()), 1);
624 /* Backwards compatibility macros put refcount during init. */
625 mod->waiter = current;
626}
627
628/* modules using other modules */
629struct module_use
630{
631 struct list_head list;
632 struct module *module_which_uses;
633};
634
635/* Does a already use b? */
636static int already_uses(struct module *a, struct module *b)
637{
638 struct module_use *use;
639
640 list_for_each_entry(use, &b->modules_which_use_me, list) {
641 if (use->module_which_uses == a) {
642 DEBUGP("%s uses %s!\n", a->name, b->name);
643 return 1;
644 }
645 }
646 DEBUGP("%s does not use %s!\n", a->name, b->name);
647 return 0;
648}
649
650/* Module a uses b */
651int use_module(struct module *a, struct module *b)
652{
653 struct module_use *use;
654 int no_warn, err;
655
656 if (b == NULL || already_uses(a, b)) return 1;
657
658 /* If we're interrupted or time out, we fail. */
659 if (wait_event_interruptible_timeout(
660 module_wq, (err = strong_try_module_get(b)) != -EBUSY,
661 30 * HZ) <= 0) {
662 printk("%s: gave up waiting for init of module %s.\n",
663 a->name, b->name);
664 return 0;
665 }
666
667 /* If strong_try_module_get() returned a different error, we fail. */
668 if (err)
669 return 0;
670
671 DEBUGP("Allocating new usage for %s.\n", a->name);
672 use = kmalloc(sizeof(*use), GFP_ATOMIC);
673 if (!use) {
674 printk("%s: out of memory loading\n", a->name);
675 module_put(b);
676 return 0;
677 }
678
679 use->module_which_uses = a;
680 list_add(&use->list, &b->modules_which_use_me);
681 no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
682 return 1;
683}
684EXPORT_SYMBOL_GPL(use_module);
685
686/* Clear the unload stuff of the module. */
687static void module_unload_free(struct module *mod)
688{
689 struct module *i;
690
691 list_for_each_entry(i, &modules, list) {
692 struct module_use *use;
693
694 list_for_each_entry(use, &i->modules_which_use_me, list) {
695 if (use->module_which_uses == mod) {
696 DEBUGP("%s unusing %s\n", mod->name, i->name);
697 module_put(i);
698 list_del(&use->list);
699 kfree(use);
700 sysfs_remove_link(i->holders_dir, mod->name);
701 /* There can be at most one match. */
702 break;
703 }
704 }
705 }
706}
707
708#ifdef CONFIG_MODULE_FORCE_UNLOAD
709static inline int try_force_unload(unsigned int flags)
710{
711 int ret = (flags & O_TRUNC);
712 if (ret)
713 add_taint(TAINT_FORCED_RMMOD);
714 return ret;
715}
716#else
717static inline int try_force_unload(unsigned int flags)
718{
719 return 0;
720}
721#endif /* CONFIG_MODULE_FORCE_UNLOAD */
722
723struct stopref
724{
725 struct module *mod;
726 int flags;
727 int *forced;
728};
729
730/* Whole machine is stopped with interrupts off when this runs. */
731static int __try_stop_module(void *_sref)
732{
733 struct stopref *sref = _sref;
734
735 /* If it's not unused, quit unless we're forcing. */
736 if (module_refcount(sref->mod) != 0) {
737 if (!(*sref->forced = try_force_unload(sref->flags)))
738 return -EWOULDBLOCK;
739 }
740
741 /* Mark it as dying. */
742 sref->mod->state = MODULE_STATE_GOING;
743 return 0;
744}
745
746static int try_stop_module(struct module *mod, int flags, int *forced)
747{
748 if (flags & O_NONBLOCK) {
749 struct stopref sref = { mod, flags, forced };
750
751 return stop_machine(__try_stop_module, &sref, NULL);
752 } else {
753 /* We don't need to stop the machine for this. */
754 mod->state = MODULE_STATE_GOING;
755 synchronize_sched();
756 return 0;
757 }
758}
759
760unsigned int module_refcount(struct module *mod)
761{
762 unsigned int total = 0;
763 int cpu;
764
765 for_each_possible_cpu(cpu)
766 total += local_read(__module_ref_addr(mod, cpu));
767 return total;
768}
769EXPORT_SYMBOL(module_refcount);
770
771/* This exists whether we can unload or not */
772static void free_module(struct module *mod);
773
774static void wait_for_zero_refcount(struct module *mod)
775{
776 /* Since we might sleep for some time, release the mutex first */
777 mutex_unlock(&module_mutex);
778 for (;;) {
779 DEBUGP("Looking at refcount...\n");
780 set_current_state(TASK_UNINTERRUPTIBLE);
781 if (module_refcount(mod) == 0)
782 break;
783 schedule();
784 }
785 current->state = TASK_RUNNING;
786 mutex_lock(&module_mutex);
787}
788
789SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
790 unsigned int, flags)
791{
792 struct module *mod;
793 char name[MODULE_NAME_LEN];
794 int ret, forced = 0;
795
796 if (!capable(CAP_SYS_MODULE) || modules_disabled)
797 return -EPERM;
798
799 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
800 return -EFAULT;
801 name[MODULE_NAME_LEN-1] = '\0';
802
803 /* Create stop_machine threads since free_module relies on
804 * a non-failing stop_machine call. */
805 ret = stop_machine_create();
806 if (ret)
807 return ret;
808
809 if (mutex_lock_interruptible(&module_mutex) != 0) {
810 ret = -EINTR;
811 goto out_stop;
812 }
813
814 mod = find_module(name);
815 if (!mod) {
816 ret = -ENOENT;
817 goto out;
818 }
819
820 if (!list_empty(&mod->modules_which_use_me)) {
821 /* Other modules depend on us: get rid of them first. */
822 ret = -EWOULDBLOCK;
823 goto out;
824 }
825
826 /* Doing init or already dying? */
827 if (mod->state != MODULE_STATE_LIVE) {
828 /* FIXME: if (force), slam module count and wake up
829 waiter --RR */
830 DEBUGP("%s already dying\n", mod->name);
831 ret = -EBUSY;
832 goto out;
833 }
834
835 /* If it has an init func, it must have an exit func to unload */
836 if (mod->init && !mod->exit) {
837 forced = try_force_unload(flags);
838 if (!forced) {
839 /* This module can't be removed */
840 ret = -EBUSY;
841 goto out;
842 }
843 }
844
845 /* Set this up before setting mod->state */
846 mod->waiter = current;
847
848 /* Stop the machine so refcounts can't move and disable module. */
849 ret = try_stop_module(mod, flags, &forced);
850 if (ret != 0)
851 goto out;
852
853 /* Never wait if forced. */
854 if (!forced && module_refcount(mod) != 0)
855 wait_for_zero_refcount(mod);
856
857 mutex_unlock(&module_mutex);
858 /* Final destruction now noone is using it. */
859 if (mod->exit != NULL)
860 mod->exit();
861 blocking_notifier_call_chain(&module_notify_list,
862 MODULE_STATE_GOING, mod);
863 async_synchronize_full();
864 mutex_lock(&module_mutex);
865 /* Store the name of the last unloaded module for diagnostic purposes */
866 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
867 ddebug_remove_module(mod->name);
868 free_module(mod);
869
870 out:
871 mutex_unlock(&module_mutex);
872out_stop:
873 stop_machine_destroy();
874 return ret;
875}
876
877static inline void print_unload_info(struct seq_file *m, struct module *mod)
878{
879 struct module_use *use;
880 int printed_something = 0;
881
882 seq_printf(m, " %u ", module_refcount(mod));
883
884 /* Always include a trailing , so userspace can differentiate
885 between this and the old multi-field proc format. */
886 list_for_each_entry(use, &mod->modules_which_use_me, list) {
887 printed_something = 1;
888 seq_printf(m, "%s,", use->module_which_uses->name);
889 }
890
891 if (mod->init != NULL && mod->exit == NULL) {
892 printed_something = 1;
893 seq_printf(m, "[permanent],");
894 }
895
896 if (!printed_something)
897 seq_printf(m, "-");
898}
899
900void __symbol_put(const char *symbol)
901{
902 struct module *owner;
903
904 preempt_disable();
905 if (!find_symbol(symbol, &owner, NULL, true, false))
906 BUG();
907 module_put(owner);
908 preempt_enable();
909}
910EXPORT_SYMBOL(__symbol_put);
911
912void symbol_put_addr(void *addr)
913{
914 struct module *modaddr;
915
916 if (core_kernel_text((unsigned long)addr))
917 return;
918
919 /* module_text_address is safe here: we're supposed to have reference
920 * to module from symbol_get, so it can't go away. */
921 modaddr = __module_text_address((unsigned long)addr);
922 BUG_ON(!modaddr);
923 module_put(modaddr);
924}
925EXPORT_SYMBOL_GPL(symbol_put_addr);
926
927static ssize_t show_refcnt(struct module_attribute *mattr,
928 struct module *mod, char *buffer)
929{
930 return sprintf(buffer, "%u\n", module_refcount(mod));
931}
932
933static struct module_attribute refcnt = {
934 .attr = { .name = "refcnt", .mode = 0444 },
935 .show = show_refcnt,
936};
937
938void module_put(struct module *module)
939{
940 if (module) {
941 unsigned int cpu = get_cpu();
942 local_dec(__module_ref_addr(module, cpu));
943 /* Maybe they're waiting for us to drop reference? */
944 if (unlikely(!module_is_live(module)))
945 wake_up_process(module->waiter);
946 put_cpu();
947 }
948}
949EXPORT_SYMBOL(module_put);
950
951#else /* !CONFIG_MODULE_UNLOAD */
952static inline void print_unload_info(struct seq_file *m, struct module *mod)
953{
954 /* We don't know the usage count, or what modules are using. */
955 seq_printf(m, " - -");
956}
957
958static inline void module_unload_free(struct module *mod)
959{
960}
961
962int use_module(struct module *a, struct module *b)
963{
964 return strong_try_module_get(b) == 0;
965}
966EXPORT_SYMBOL_GPL(use_module);
967
968static inline void module_unload_init(struct module *mod)
969{
970}
971#endif /* CONFIG_MODULE_UNLOAD */
972
973static ssize_t show_initstate(struct module_attribute *mattr,
974 struct module *mod, char *buffer)
975{
976 const char *state = "unknown";
977
978 switch (mod->state) {
979 case MODULE_STATE_LIVE:
980 state = "live";
981 break;
982 case MODULE_STATE_COMING:
983 state = "coming";
984 break;
985 case MODULE_STATE_GOING:
986 state = "going";
987 break;
988 }
989 return sprintf(buffer, "%s\n", state);
990}
991
992static struct module_attribute initstate = {
993 .attr = { .name = "initstate", .mode = 0444 },
994 .show = show_initstate,
995};
996
997static struct module_attribute *modinfo_attrs[] = {
998 &modinfo_version,
999 &modinfo_srcversion,
1000 &initstate,
1001#ifdef CONFIG_MODULE_UNLOAD
1002 &refcnt,
1003#endif
1004 NULL,
1005};
1006
1007static const char vermagic[] = VERMAGIC_STRING;
1008
1009static int try_to_force_load(struct module *mod, const char *reason)
1010{
1011#ifdef CONFIG_MODULE_FORCE_LOAD
1012 if (!test_taint(TAINT_FORCED_MODULE))
1013 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
1014 mod->name, reason);
1015 add_taint_module(mod, TAINT_FORCED_MODULE);
1016 return 0;
1017#else
1018 return -ENOEXEC;
1019#endif
1020}
1021
1022#ifdef CONFIG_MODVERSIONS
1023static int check_version(Elf_Shdr *sechdrs,
1024 unsigned int versindex,
1025 const char *symname,
1026 struct module *mod,
1027 const unsigned long *crc)
1028{
1029 unsigned int i, num_versions;
1030 struct modversion_info *versions;
1031
1032 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1033 if (!crc)
1034 return 1;
1035
1036 /* No versions at all? modprobe --force does this. */
1037 if (versindex == 0)
1038 return try_to_force_load(mod, symname) == 0;
1039
1040 versions = (void *) sechdrs[versindex].sh_addr;
1041 num_versions = sechdrs[versindex].sh_size
1042 / sizeof(struct modversion_info);
1043
1044 for (i = 0; i < num_versions; i++) {
1045 if (strcmp(versions[i].name, symname) != 0)
1046 continue;
1047
1048 if (versions[i].crc == *crc)
1049 return 1;
1050 DEBUGP("Found checksum %lX vs module %lX\n",
1051 *crc, versions[i].crc);
1052 goto bad_version;
1053 }
1054
1055 printk(KERN_WARNING "%s: no symbol version for %s\n",
1056 mod->name, symname);
1057 return 0;
1058
1059bad_version:
1060 printk("%s: disagrees about version of symbol %s\n",
1061 mod->name, symname);
1062 return 0;
1063}
1064
1065static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1066 unsigned int versindex,
1067 struct module *mod)
1068{
1069 const unsigned long *crc;
1070
1071 if (!find_symbol("module_layout", NULL, &crc, true, false))
1072 BUG();
1073 return check_version(sechdrs, versindex, "module_layout", mod, crc);
1074}
1075
1076/* First part is kernel version, which we ignore if module has crcs. */
1077static inline int same_magic(const char *amagic, const char *bmagic,
1078 bool has_crcs)
1079{
1080 if (has_crcs) {
1081 amagic += strcspn(amagic, " ");
1082 bmagic += strcspn(bmagic, " ");
1083 }
1084 return strcmp(amagic, bmagic) == 0;
1085}
1086#else
1087static inline int check_version(Elf_Shdr *sechdrs,
1088 unsigned int versindex,
1089 const char *symname,
1090 struct module *mod,
1091 const unsigned long *crc)
1092{
1093 return 1;
1094}
1095
1096static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1097 unsigned int versindex,
1098 struct module *mod)
1099{
1100 return 1;
1101}
1102
1103static inline int same_magic(const char *amagic, const char *bmagic,
1104 bool has_crcs)
1105{
1106 return strcmp(amagic, bmagic) == 0;
1107}
1108#endif /* CONFIG_MODVERSIONS */
1109
1110/* Resolve a symbol for this module. I.e. if we find one, record usage.
1111 Must be holding module_mutex. */
1112static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
1113 unsigned int versindex,
1114 const char *name,
1115 struct module *mod)
1116{
1117 struct module *owner;
1118 const struct kernel_symbol *sym;
1119 const unsigned long *crc;
1120
1121 sym = find_symbol(name, &owner, &crc,
1122 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1123 /* use_module can fail due to OOM,
1124 or module initialization or unloading */
1125 if (sym) {
1126 if (!check_version(sechdrs, versindex, name, mod, crc) ||
1127 !use_module(mod, owner))
1128 sym = NULL;
1129 }
1130 return sym;
1131}
1132
1133/*
1134 * /sys/module/foo/sections stuff
1135 * J. Corbet <[email protected]>
1136 */
1137#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1138struct module_sect_attr
1139{
1140 struct module_attribute mattr;
1141 char *name;
1142 unsigned long address;
1143};
1144
1145struct module_sect_attrs
1146{
1147 struct attribute_group grp;
1148 unsigned int nsections;
1149 struct module_sect_attr attrs[0];
1150};
1151
1152static ssize_t module_sect_show(struct module_attribute *mattr,
1153 struct module *mod, char *buf)
1154{
1155 struct module_sect_attr *sattr =
1156 container_of(mattr, struct module_sect_attr, mattr);
1157 return sprintf(buf, "0x%lx\n", sattr->address);
1158}
1159
1160static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1161{
1162 unsigned int section;
1163
1164 for (section = 0; section < sect_attrs->nsections; section++)
1165 kfree(sect_attrs->attrs[section].name);
1166 kfree(sect_attrs);
1167}
1168
1169static void add_sect_attrs(struct module *mod, unsigned int nsect,
1170 char *secstrings, Elf_Shdr *sechdrs)
1171{
1172 unsigned int nloaded = 0, i, size[2];
1173 struct module_sect_attrs *sect_attrs;
1174 struct module_sect_attr *sattr;
1175 struct attribute **gattr;
1176
1177 /* Count loaded sections and allocate structures */
1178 for (i = 0; i < nsect; i++)
1179 if (sechdrs[i].sh_flags & SHF_ALLOC)
1180 nloaded++;
1181 size[0] = ALIGN(sizeof(*sect_attrs)
1182 + nloaded * sizeof(sect_attrs->attrs[0]),
1183 sizeof(sect_attrs->grp.attrs[0]));
1184 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1185 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1186 if (sect_attrs == NULL)
1187 return;
1188
1189 /* Setup section attributes. */
1190 sect_attrs->grp.name = "sections";
1191 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1192
1193 sect_attrs->nsections = 0;
1194 sattr = &sect_attrs->attrs[0];
1195 gattr = &sect_attrs->grp.attrs[0];
1196 for (i = 0; i < nsect; i++) {
1197 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1198 continue;
1199 sattr->address = sechdrs[i].sh_addr;
1200 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1201 GFP_KERNEL);
1202 if (sattr->name == NULL)
1203 goto out;
1204 sect_attrs->nsections++;
1205 sattr->mattr.show = module_sect_show;
1206 sattr->mattr.store = NULL;
1207 sattr->mattr.attr.name = sattr->name;
1208 sattr->mattr.attr.mode = S_IRUGO;
1209 *(gattr++) = &(sattr++)->mattr.attr;
1210 }
1211 *gattr = NULL;
1212
1213 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1214 goto out;
1215
1216 mod->sect_attrs = sect_attrs;
1217 return;
1218 out:
1219 free_sect_attrs(sect_attrs);
1220}
1221
1222static void remove_sect_attrs(struct module *mod)
1223{
1224 if (mod->sect_attrs) {
1225 sysfs_remove_group(&mod->mkobj.kobj,
1226 &mod->sect_attrs->grp);
1227 /* We are positive that no one is using any sect attrs
1228 * at this point. Deallocate immediately. */
1229 free_sect_attrs(mod->sect_attrs);
1230 mod->sect_attrs = NULL;
1231 }
1232}
1233
1234/*
1235 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1236 */
1237
1238struct module_notes_attrs {
1239 struct kobject *dir;
1240 unsigned int notes;
1241 struct bin_attribute attrs[0];
1242};
1243
1244static ssize_t module_notes_read(struct kobject *kobj,
1245 struct bin_attribute *bin_attr,
1246 char *buf, loff_t pos, size_t count)
1247{
1248 /*
1249 * The caller checked the pos and count against our size.
1250 */
1251 memcpy(buf, bin_attr->private + pos, count);
1252 return count;
1253}
1254
1255static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1256 unsigned int i)
1257{
1258 if (notes_attrs->dir) {
1259 while (i-- > 0)
1260 sysfs_remove_bin_file(notes_attrs->dir,
1261 &notes_attrs->attrs[i]);
1262 kobject_put(notes_attrs->dir);
1263 }
1264 kfree(notes_attrs);
1265}
1266
1267static void add_notes_attrs(struct module *mod, unsigned int nsect,
1268 char *secstrings, Elf_Shdr *sechdrs)
1269{
1270 unsigned int notes, loaded, i;
1271 struct module_notes_attrs *notes_attrs;
1272 struct bin_attribute *nattr;
1273
1274 /* Count notes sections and allocate structures. */
1275 notes = 0;
1276 for (i = 0; i < nsect; i++)
1277 if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
1278 (sechdrs[i].sh_type == SHT_NOTE))
1279 ++notes;
1280
1281 if (notes == 0)
1282 return;
1283
1284 notes_attrs = kzalloc(sizeof(*notes_attrs)
1285 + notes * sizeof(notes_attrs->attrs[0]),
1286 GFP_KERNEL);
1287 if (notes_attrs == NULL)
1288 return;
1289
1290 notes_attrs->notes = notes;
1291 nattr = &notes_attrs->attrs[0];
1292 for (loaded = i = 0; i < nsect; ++i) {
1293 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1294 continue;
1295 if (sechdrs[i].sh_type == SHT_NOTE) {
1296 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1297 nattr->attr.mode = S_IRUGO;
1298 nattr->size = sechdrs[i].sh_size;
1299 nattr->private = (void *) sechdrs[i].sh_addr;
1300 nattr->read = module_notes_read;
1301 ++nattr;
1302 }
1303 ++loaded;
1304 }
1305
1306 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1307 if (!notes_attrs->dir)
1308 goto out;
1309
1310 for (i = 0; i < notes; ++i)
1311 if (sysfs_create_bin_file(notes_attrs->dir,
1312 &notes_attrs->attrs[i]))
1313 goto out;
1314
1315 mod->notes_attrs = notes_attrs;
1316 return;
1317
1318 out:
1319 free_notes_attrs(notes_attrs, i);
1320}
1321
1322static void remove_notes_attrs(struct module *mod)
1323{
1324 if (mod->notes_attrs)
1325 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1326}
1327
1328#else
1329
1330static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1331 char *sectstrings, Elf_Shdr *sechdrs)
1332{
1333}
1334
1335static inline void remove_sect_attrs(struct module *mod)
1336{
1337}
1338
1339static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1340 char *sectstrings, Elf_Shdr *sechdrs)
1341{
1342}
1343
1344static inline void remove_notes_attrs(struct module *mod)
1345{
1346}
1347#endif
1348
1349#ifdef CONFIG_SYSFS
1350int module_add_modinfo_attrs(struct module *mod)
1351{
1352 struct module_attribute *attr;
1353 struct module_attribute *temp_attr;
1354 int error = 0;
1355 int i;
1356
1357 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1358 (ARRAY_SIZE(modinfo_attrs) + 1)),
1359 GFP_KERNEL);
1360 if (!mod->modinfo_attrs)
1361 return -ENOMEM;
1362
1363 temp_attr = mod->modinfo_attrs;
1364 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1365 if (!attr->test ||
1366 (attr->test && attr->test(mod))) {
1367 memcpy(temp_attr, attr, sizeof(*temp_attr));
1368 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1369 ++temp_attr;
1370 }
1371 }
1372 return error;
1373}
1374
1375void module_remove_modinfo_attrs(struct module *mod)
1376{
1377 struct module_attribute *attr;
1378 int i;
1379
1380 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1381 /* pick a field to test for end of list */
1382 if (!attr->attr.name)
1383 break;
1384 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1385 if (attr->free)
1386 attr->free(mod);
1387 }
1388 kfree(mod->modinfo_attrs);
1389}
1390
1391int mod_sysfs_init(struct module *mod)
1392{
1393 int err;
1394 struct kobject *kobj;
1395
1396 if (!module_sysfs_initialized) {
1397 printk(KERN_ERR "%s: module sysfs not initialized\n",
1398 mod->name);
1399 err = -EINVAL;
1400 goto out;
1401 }
1402
1403 kobj = kset_find_obj(module_kset, mod->name);
1404 if (kobj) {
1405 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1406 kobject_put(kobj);
1407 err = -EINVAL;
1408 goto out;
1409 }
1410
1411 mod->mkobj.mod = mod;
1412
1413 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1414 mod->mkobj.kobj.kset = module_kset;
1415 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1416 "%s", mod->name);
1417 if (err)
1418 kobject_put(&mod->mkobj.kobj);
1419
1420 /* delay uevent until full sysfs population */
1421out:
1422 return err;
1423}
1424
1425int mod_sysfs_setup(struct module *mod,
1426 struct kernel_param *kparam,
1427 unsigned int num_params)
1428{
1429 int err;
1430
1431 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1432 if (!mod->holders_dir) {
1433 err = -ENOMEM;
1434 goto out_unreg;
1435 }
1436
1437 err = module_param_sysfs_setup(mod, kparam, num_params);
1438 if (err)
1439 goto out_unreg_holders;
1440
1441 err = module_add_modinfo_attrs(mod);
1442 if (err)
1443 goto out_unreg_param;
1444
1445 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1446 return 0;
1447
1448out_unreg_param:
1449 module_param_sysfs_remove(mod);
1450out_unreg_holders:
1451 kobject_put(mod->holders_dir);
1452out_unreg:
1453 kobject_put(&mod->mkobj.kobj);
1454 return err;
1455}
1456
1457static void mod_sysfs_fini(struct module *mod)
1458{
1459 kobject_put(&mod->mkobj.kobj);
1460}
1461
1462#else /* CONFIG_SYSFS */
1463
1464static void mod_sysfs_fini(struct module *mod)
1465{
1466}
1467
1468#endif /* CONFIG_SYSFS */
1469
1470static void mod_kobject_remove(struct module *mod)
1471{
1472 module_remove_modinfo_attrs(mod);
1473 module_param_sysfs_remove(mod);
1474 kobject_put(mod->mkobj.drivers_dir);
1475 kobject_put(mod->holders_dir);
1476 mod_sysfs_fini(mod);
1477}
1478
1479/*
1480 * unlink the module with the whole machine is stopped with interrupts off
1481 * - this defends against kallsyms not taking locks
1482 */
1483static int __unlink_module(void *_mod)
1484{
1485 struct module *mod = _mod;
1486 list_del(&mod->list);
1487 return 0;
1488}
1489
1490/* Free a module, remove from lists, etc (must hold module_mutex). */
1491static void free_module(struct module *mod)
1492{
1493 /* Delete from various lists */
1494 stop_machine(__unlink_module, mod, NULL);
1495 remove_notes_attrs(mod);
1496 remove_sect_attrs(mod);
1497 mod_kobject_remove(mod);
1498
1499 /* Arch-specific cleanup. */
1500 module_arch_cleanup(mod);
1501
1502 /* Module unload stuff */
1503 module_unload_free(mod);
1504
1505 /* Free any allocated parameters. */
1506 destroy_params(mod->kp, mod->num_kp);
1507
1508 /* This may be NULL, but that's OK */
1509 module_free(mod, mod->module_init);
1510 kfree(mod->args);
1511 if (mod->percpu)
1512 percpu_modfree(mod->percpu);
1513#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
1514 if (mod->refptr)
1515 percpu_modfree(mod->refptr);
1516#endif
1517 /* Free lock-classes: */
1518 lockdep_free_key_range(mod->module_core, mod->core_size);
1519
1520 /* Finally, free the core (containing the module structure) */
1521 module_free(mod, mod->module_core);
1522}
1523
1524void *__symbol_get(const char *symbol)
1525{
1526 struct module *owner;
1527 const struct kernel_symbol *sym;
1528
1529 preempt_disable();
1530 sym = find_symbol(symbol, &owner, NULL, true, true);
1531 if (sym && strong_try_module_get(owner))
1532 sym = NULL;
1533 preempt_enable();
1534
1535 return sym ? (void *)sym->value : NULL;
1536}
1537EXPORT_SYMBOL_GPL(__symbol_get);
1538
1539/*
1540 * Ensure that an exported symbol [global namespace] does not already exist
1541 * in the kernel or in some other module's exported symbol table.
1542 */
1543static int verify_export_symbols(struct module *mod)
1544{
1545 unsigned int i;
1546 struct module *owner;
1547 const struct kernel_symbol *s;
1548 struct {
1549 const struct kernel_symbol *sym;
1550 unsigned int num;
1551 } arr[] = {
1552 { mod->syms, mod->num_syms },
1553 { mod->gpl_syms, mod->num_gpl_syms },
1554 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1555#ifdef CONFIG_UNUSED_SYMBOLS
1556 { mod->unused_syms, mod->num_unused_syms },
1557 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1558#endif
1559 };
1560
1561 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1562 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1563 if (find_symbol(s->name, &owner, NULL, true, false)) {
1564 printk(KERN_ERR
1565 "%s: exports duplicate symbol %s"
1566 " (owned by %s)\n",
1567 mod->name, s->name, module_name(owner));
1568 return -ENOEXEC;
1569 }
1570 }
1571 }
1572 return 0;
1573}
1574
1575/* Change all symbols so that st_value encodes the pointer directly. */
1576static int simplify_symbols(Elf_Shdr *sechdrs,
1577 unsigned int symindex,
1578 const char *strtab,
1579 unsigned int versindex,
1580 unsigned int pcpuindex,
1581 struct module *mod)
1582{
1583 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1584 unsigned long secbase;
1585 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1586 int ret = 0;
1587 const struct kernel_symbol *ksym;
1588
1589 for (i = 1; i < n; i++) {
1590 switch (sym[i].st_shndx) {
1591 case SHN_COMMON:
1592 /* We compiled with -fno-common. These are not
1593 supposed to happen. */
1594 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1595 printk("%s: please compile with -fno-common\n",
1596 mod->name);
1597 ret = -ENOEXEC;
1598 break;
1599
1600 case SHN_ABS:
1601 /* Don't need to do anything */
1602 DEBUGP("Absolute symbol: 0x%08lx\n",
1603 (long)sym[i].st_value);
1604 break;
1605
1606 case SHN_UNDEF:
1607 ksym = resolve_symbol(sechdrs, versindex,
1608 strtab + sym[i].st_name, mod);
1609 /* Ok if resolved. */
1610 if (ksym) {
1611 sym[i].st_value = ksym->value;
1612 break;
1613 }
1614
1615 /* Ok if weak. */
1616 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1617 break;
1618
1619 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1620 mod->name, strtab + sym[i].st_name);
1621 ret = -ENOENT;
1622 break;
1623
1624 default:
1625 /* Divert to percpu allocation if a percpu var. */
1626 if (sym[i].st_shndx == pcpuindex)
1627 secbase = (unsigned long)mod->percpu;
1628 else
1629 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1630 sym[i].st_value += secbase;
1631 break;
1632 }
1633 }
1634
1635 return ret;
1636}
1637
1638/* Additional bytes needed by arch in front of individual sections */
1639unsigned int __weak arch_mod_section_prepend(struct module *mod,
1640 unsigned int section)
1641{
1642 /* default implementation just returns zero */
1643 return 0;
1644}
1645
1646/* Update size with this section: return offset. */
1647static long get_offset(struct module *mod, unsigned int *size,
1648 Elf_Shdr *sechdr, unsigned int section)
1649{
1650 long ret;
1651
1652 *size += arch_mod_section_prepend(mod, section);
1653 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1654 *size = ret + sechdr->sh_size;
1655 return ret;
1656}
1657
1658/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1659 might -- code, read-only data, read-write data, small data. Tally
1660 sizes, and place the offsets into sh_entsize fields: high bit means it
1661 belongs in init. */
1662static void layout_sections(struct module *mod,
1663 const Elf_Ehdr *hdr,
1664 Elf_Shdr *sechdrs,
1665 const char *secstrings)
1666{
1667 static unsigned long const masks[][2] = {
1668 /* NOTE: all executable code must be the first section
1669 * in this array; otherwise modify the text_size
1670 * finder in the two loops below */
1671 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1672 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1673 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1674 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1675 };
1676 unsigned int m, i;
1677
1678 for (i = 0; i < hdr->e_shnum; i++)
1679 sechdrs[i].sh_entsize = ~0UL;
1680
1681 DEBUGP("Core section allocation order:\n");
1682 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1683 for (i = 0; i < hdr->e_shnum; ++i) {
1684 Elf_Shdr *s = &sechdrs[i];
1685
1686 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1687 || (s->sh_flags & masks[m][1])
1688 || s->sh_entsize != ~0UL
1689 || strstarts(secstrings + s->sh_name, ".init"))
1690 continue;
1691 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1692 DEBUGP("\t%s\n", secstrings + s->sh_name);
1693 }
1694 if (m == 0)
1695 mod->core_text_size = mod->core_size;
1696 }
1697
1698 DEBUGP("Init section allocation order:\n");
1699 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1700 for (i = 0; i < hdr->e_shnum; ++i) {
1701 Elf_Shdr *s = &sechdrs[i];
1702
1703 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1704 || (s->sh_flags & masks[m][1])
1705 || s->sh_entsize != ~0UL
1706 || !strstarts(secstrings + s->sh_name, ".init"))
1707 continue;
1708 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1709 | INIT_OFFSET_MASK);
1710 DEBUGP("\t%s\n", secstrings + s->sh_name);
1711 }
1712 if (m == 0)
1713 mod->init_text_size = mod->init_size;
1714 }
1715}
1716
1717static void set_license(struct module *mod, const char *license)
1718{
1719 if (!license)
1720 license = "unspecified";
1721
1722 if (!license_is_gpl_compatible(license)) {
1723 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1724 printk(KERN_WARNING "%s: module license '%s' taints "
1725 "kernel.\n", mod->name, license);
1726 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1727 }
1728}
1729
1730/* Parse tag=value strings from .modinfo section */
1731static char *next_string(char *string, unsigned long *secsize)
1732{
1733 /* Skip non-zero chars */
1734 while (string[0]) {
1735 string++;
1736 if ((*secsize)-- <= 1)
1737 return NULL;
1738 }
1739
1740 /* Skip any zero padding. */
1741 while (!string[0]) {
1742 string++;
1743 if ((*secsize)-- <= 1)
1744 return NULL;
1745 }
1746 return string;
1747}
1748
1749static char *get_modinfo(Elf_Shdr *sechdrs,
1750 unsigned int info,
1751 const char *tag)
1752{
1753 char *p;
1754 unsigned int taglen = strlen(tag);
1755 unsigned long size = sechdrs[info].sh_size;
1756
1757 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1758 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1759 return p + taglen + 1;
1760 }
1761 return NULL;
1762}
1763
1764static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1765 unsigned int infoindex)
1766{
1767 struct module_attribute *attr;
1768 int i;
1769
1770 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1771 if (attr->setup)
1772 attr->setup(mod,
1773 get_modinfo(sechdrs,
1774 infoindex,
1775 attr->attr.name));
1776 }
1777}
1778
1779#ifdef CONFIG_KALLSYMS
1780
1781/* lookup symbol in given range of kernel_symbols */
1782static const struct kernel_symbol *lookup_symbol(const char *name,
1783 const struct kernel_symbol *start,
1784 const struct kernel_symbol *stop)
1785{
1786 const struct kernel_symbol *ks = start;
1787 for (; ks < stop; ks++)
1788 if (strcmp(ks->name, name) == 0)
1789 return ks;
1790 return NULL;
1791}
1792
1793static int is_exported(const char *name, unsigned long value,
1794 const struct module *mod)
1795{
1796 const struct kernel_symbol *ks;
1797 if (!mod)
1798 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1799 else
1800 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1801 return ks != NULL && ks->value == value;
1802}
1803
1804/* As per nm */
1805static char elf_type(const Elf_Sym *sym,
1806 Elf_Shdr *sechdrs,
1807 const char *secstrings,
1808 struct module *mod)
1809{
1810 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1811 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1812 return 'v';
1813 else
1814 return 'w';
1815 }
1816 if (sym->st_shndx == SHN_UNDEF)
1817 return 'U';
1818 if (sym->st_shndx == SHN_ABS)
1819 return 'a';
1820 if (sym->st_shndx >= SHN_LORESERVE)
1821 return '?';
1822 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1823 return 't';
1824 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1825 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1826 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1827 return 'r';
1828 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1829 return 'g';
1830 else
1831 return 'd';
1832 }
1833 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1834 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1835 return 's';
1836 else
1837 return 'b';
1838 }
1839 if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug"))
1840 return 'n';
1841 return '?';
1842}
1843
1844static void add_kallsyms(struct module *mod,
1845 Elf_Shdr *sechdrs,
1846 unsigned int symindex,
1847 unsigned int strindex,
1848 const char *secstrings)
1849{
1850 unsigned int i;
1851
1852 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1853 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1854 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1855
1856 /* Set types up while we still have access to sections. */
1857 for (i = 0; i < mod->num_symtab; i++)
1858 mod->symtab[i].st_info
1859 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1860}
1861#else
1862static inline void add_kallsyms(struct module *mod,
1863 Elf_Shdr *sechdrs,
1864 unsigned int symindex,
1865 unsigned int strindex,
1866 const char *secstrings)
1867{
1868}
1869#endif /* CONFIG_KALLSYMS */
1870
1871static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
1872{
1873#ifdef CONFIG_DYNAMIC_DEBUG
1874 if (ddebug_add_module(debug, num, debug->modname))
1875 printk(KERN_ERR "dynamic debug error adding module: %s\n",
1876 debug->modname);
1877#endif
1878}
1879
1880static void *module_alloc_update_bounds(unsigned long size)
1881{
1882 void *ret = module_alloc(size);
1883
1884 if (ret) {
1885 /* Update module bounds. */
1886 if ((unsigned long)ret < module_addr_min)
1887 module_addr_min = (unsigned long)ret;
1888 if ((unsigned long)ret + size > module_addr_max)
1889 module_addr_max = (unsigned long)ret + size;
1890 }
1891 return ret;
1892}
1893
1894#ifdef CONFIG_DEBUG_KMEMLEAK
1895static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
1896 Elf_Shdr *sechdrs, char *secstrings)
1897{
1898 unsigned int i;
1899
1900 /* only scan the sections containing data */
1901 kmemleak_scan_area(mod->module_core, (unsigned long)mod -
1902 (unsigned long)mod->module_core,
1903 sizeof(struct module), GFP_KERNEL);
1904
1905 for (i = 1; i < hdr->e_shnum; i++) {
1906 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1907 continue;
1908 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
1909 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
1910 continue;
1911
1912 kmemleak_scan_area(mod->module_core, sechdrs[i].sh_addr -
1913 (unsigned long)mod->module_core,
1914 sechdrs[i].sh_size, GFP_KERNEL);
1915 }
1916}
1917#else
1918static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
1919 Elf_Shdr *sechdrs, char *secstrings)
1920{
1921}
1922#endif
1923
1924/* Allocate and load the module: note that size of section 0 is always
1925 zero, and we rely on this for optional sections. */
1926static noinline struct module *load_module(void __user *umod,
1927 unsigned long len,
1928 const char __user *uargs)
1929{
1930 Elf_Ehdr *hdr;
1931 Elf_Shdr *sechdrs;
1932 char *secstrings, *args, *modmagic, *strtab = NULL;
1933 char *staging;
1934 unsigned int i;
1935 unsigned int symindex = 0;
1936 unsigned int strindex = 0;
1937 unsigned int modindex, versindex, infoindex, pcpuindex;
1938 struct module *mod;
1939 long err = 0;
1940 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1941 mm_segment_t old_fs;
1942
1943 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1944 umod, len, uargs);
1945 if (len < sizeof(*hdr))
1946 return ERR_PTR(-ENOEXEC);
1947
1948 /* Suck in entire file: we'll want most of it. */
1949 /* vmalloc barfs on "unusual" numbers. Check here */
1950 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1951 return ERR_PTR(-ENOMEM);
1952
1953 if (copy_from_user(hdr, umod, len) != 0) {
1954 err = -EFAULT;
1955 goto free_hdr;
1956 }
1957
1958 /* Sanity checks against insmoding binaries or wrong arch,
1959 weird elf version */
1960 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
1961 || hdr->e_type != ET_REL
1962 || !elf_check_arch(hdr)
1963 || hdr->e_shentsize != sizeof(*sechdrs)) {
1964 err = -ENOEXEC;
1965 goto free_hdr;
1966 }
1967
1968 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1969 goto truncated;
1970
1971 /* Convenience variables */
1972 sechdrs = (void *)hdr + hdr->e_shoff;
1973 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1974 sechdrs[0].sh_addr = 0;
1975
1976 for (i = 1; i < hdr->e_shnum; i++) {
1977 if (sechdrs[i].sh_type != SHT_NOBITS
1978 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1979 goto truncated;
1980
1981 /* Mark all sections sh_addr with their address in the
1982 temporary image. */
1983 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1984
1985 /* Internal symbols and strings. */
1986 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1987 symindex = i;
1988 strindex = sechdrs[i].sh_link;
1989 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
1990 }
1991#ifndef CONFIG_MODULE_UNLOAD
1992 /* Don't load .exit sections */
1993 if (strstarts(secstrings+sechdrs[i].sh_name, ".exit"))
1994 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
1995#endif
1996 }
1997
1998 modindex = find_sec(hdr, sechdrs, secstrings,
1999 ".gnu.linkonce.this_module");
2000 if (!modindex) {
2001 printk(KERN_WARNING "No module found in object\n");
2002 err = -ENOEXEC;
2003 goto free_hdr;
2004 }
2005 /* This is temporary: point mod into copy of data. */
2006 mod = (void *)sechdrs[modindex].sh_addr;
2007
2008 if (symindex == 0) {
2009 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2010 mod->name);
2011 err = -ENOEXEC;
2012 goto free_hdr;
2013 }
2014
2015 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
2016 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
2017 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
2018
2019 /* Don't keep modinfo and version sections. */
2020 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2021 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2022#ifdef CONFIG_KALLSYMS
2023 /* Keep symbol and string tables for decoding later. */
2024 sechdrs[symindex].sh_flags |= SHF_ALLOC;
2025 sechdrs[strindex].sh_flags |= SHF_ALLOC;
2026#endif
2027
2028 /* Check module struct version now, before we try to use module. */
2029 if (!check_modstruct_version(sechdrs, versindex, mod)) {
2030 err = -ENOEXEC;
2031 goto free_hdr;
2032 }
2033
2034 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2035 /* This is allowed: modprobe --force will invalidate it. */
2036 if (!modmagic) {
2037 err = try_to_force_load(mod, "bad vermagic");
2038 if (err)
2039 goto free_hdr;
2040 } else if (!same_magic(modmagic, vermagic, versindex)) {
2041 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2042 mod->name, modmagic, vermagic);
2043 err = -ENOEXEC;
2044 goto free_hdr;
2045 }
2046
2047 staging = get_modinfo(sechdrs, infoindex, "staging");
2048 if (staging) {
2049 add_taint_module(mod, TAINT_CRAP);
2050 printk(KERN_WARNING "%s: module is from the staging directory,"
2051 " the quality is unknown, you have been warned.\n",
2052 mod->name);
2053 }
2054
2055 /* Now copy in args */
2056 args = strndup_user(uargs, ~0UL >> 1);
2057 if (IS_ERR(args)) {
2058 err = PTR_ERR(args);
2059 goto free_hdr;
2060 }
2061
2062 if (find_module(mod->name)) {
2063 err = -EEXIST;
2064 goto free_mod;
2065 }
2066
2067 mod->state = MODULE_STATE_COMING;
2068
2069 /* Allow arches to frob section contents and sizes. */
2070 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
2071 if (err < 0)
2072 goto free_mod;
2073
2074 if (pcpuindex) {
2075 /* We have a special allocation for this section. */
2076 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
2077 sechdrs[pcpuindex].sh_addralign,
2078 mod->name);
2079 if (!percpu) {
2080 err = -ENOMEM;
2081 goto free_mod;
2082 }
2083 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2084 mod->percpu = percpu;
2085 }
2086
2087 /* Determine total sizes, and put offsets in sh_entsize. For now
2088 this is done generically; there doesn't appear to be any
2089 special cases for the architectures. */
2090 layout_sections(mod, hdr, sechdrs, secstrings);
2091
2092 /* Do the allocs. */
2093 ptr = module_alloc_update_bounds(mod->core_size);
2094 /*
2095 * The pointer to this block is stored in the module structure
2096 * which is inside the block. Just mark it as not being a
2097 * leak.
2098 */
2099 kmemleak_not_leak(ptr);
2100 if (!ptr) {
2101 err = -ENOMEM;
2102 goto free_percpu;
2103 }
2104 memset(ptr, 0, mod->core_size);
2105 mod->module_core = ptr;
2106
2107 ptr = module_alloc_update_bounds(mod->init_size);
2108 /*
2109 * The pointer to this block is stored in the module structure
2110 * which is inside the block. This block doesn't need to be
2111 * scanned as it contains data and code that will be freed
2112 * after the module is initialized.
2113 */
2114 kmemleak_ignore(ptr);
2115 if (!ptr && mod->init_size) {
2116 err = -ENOMEM;
2117 goto free_core;
2118 }
2119 memset(ptr, 0, mod->init_size);
2120 mod->module_init = ptr;
2121
2122 /* Transfer each section which specifies SHF_ALLOC */
2123 DEBUGP("final section addresses:\n");
2124 for (i = 0; i < hdr->e_shnum; i++) {
2125 void *dest;
2126
2127 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2128 continue;
2129
2130 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2131 dest = mod->module_init
2132 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2133 else
2134 dest = mod->module_core + sechdrs[i].sh_entsize;
2135
2136 if (sechdrs[i].sh_type != SHT_NOBITS)
2137 memcpy(dest, (void *)sechdrs[i].sh_addr,
2138 sechdrs[i].sh_size);
2139 /* Update sh_addr to point to copy in image. */
2140 sechdrs[i].sh_addr = (unsigned long)dest;
2141 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2142 }
2143 /* Module has been moved. */
2144 mod = (void *)sechdrs[modindex].sh_addr;
2145 kmemleak_load_module(mod, hdr, sechdrs, secstrings);
2146
2147#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
2148 mod->refptr = percpu_modalloc(sizeof(local_t), __alignof__(local_t),
2149 mod->name);
2150 if (!mod->refptr) {
2151 err = -ENOMEM;
2152 goto free_init;
2153 }
2154#endif
2155 /* Now we've moved module, initialize linked lists, etc. */
2156 module_unload_init(mod);
2157
2158 /* add kobject, so we can reference it. */
2159 err = mod_sysfs_init(mod);
2160 if (err)
2161 goto free_unload;
2162
2163 /* Set up license info based on the info section */
2164 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2165
2166 /*
2167 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2168 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2169 * using GPL-only symbols it needs.
2170 */
2171 if (strcmp(mod->name, "ndiswrapper") == 0)
2172 add_taint(TAINT_PROPRIETARY_MODULE);
2173
2174 /* driverloader was caught wrongly pretending to be under GPL */
2175 if (strcmp(mod->name, "driverloader") == 0)
2176 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2177
2178 /* Set up MODINFO_ATTR fields */
2179 setup_modinfo(mod, sechdrs, infoindex);
2180
2181 /* Fix up syms, so that st_value is a pointer to location. */
2182 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2183 mod);
2184 if (err < 0)
2185 goto cleanup;
2186
2187 /* Now we've got everything in the final locations, we can
2188 * find optional sections. */
2189 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2190 sizeof(*mod->kp), &mod->num_kp);
2191 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2192 sizeof(*mod->syms), &mod->num_syms);
2193 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2194 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2195 sizeof(*mod->gpl_syms),
2196 &mod->num_gpl_syms);
2197 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2198 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2199 "__ksymtab_gpl_future",
2200 sizeof(*mod->gpl_future_syms),
2201 &mod->num_gpl_future_syms);
2202 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2203 "__kcrctab_gpl_future");
2204
2205#ifdef CONFIG_UNUSED_SYMBOLS
2206 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2207 "__ksymtab_unused",
2208 sizeof(*mod->unused_syms),
2209 &mod->num_unused_syms);
2210 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2211 "__kcrctab_unused");
2212 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2213 "__ksymtab_unused_gpl",
2214 sizeof(*mod->unused_gpl_syms),
2215 &mod->num_unused_gpl_syms);
2216 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2217 "__kcrctab_unused_gpl");
2218#endif
2219#ifdef CONFIG_CONSTRUCTORS
2220 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2221 sizeof(*mod->ctors), &mod->num_ctors);
2222#endif
2223
2224#ifdef CONFIG_MARKERS
2225 mod->markers = section_objs(hdr, sechdrs, secstrings, "__markers",
2226 sizeof(*mod->markers), &mod->num_markers);
2227#endif
2228#ifdef CONFIG_TRACEPOINTS
2229 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2230 "__tracepoints",
2231 sizeof(*mod->tracepoints),
2232 &mod->num_tracepoints);
2233#endif
2234#ifdef CONFIG_EVENT_TRACING
2235 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2236 "_ftrace_events",
2237 sizeof(*mod->trace_events),
2238 &mod->num_trace_events);
2239#endif
2240#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2241 /* sechdrs[0].sh_size is always zero */
2242 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2243 "__mcount_loc",
2244 sizeof(*mod->ftrace_callsites),
2245 &mod->num_ftrace_callsites);
2246#endif
2247#ifdef CONFIG_MODVERSIONS
2248 if ((mod->num_syms && !mod->crcs)
2249 || (mod->num_gpl_syms && !mod->gpl_crcs)
2250 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2251#ifdef CONFIG_UNUSED_SYMBOLS
2252 || (mod->num_unused_syms && !mod->unused_crcs)
2253 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2254#endif
2255 ) {
2256 err = try_to_force_load(mod,
2257 "no versions for exported symbols");
2258 if (err)
2259 goto cleanup;
2260 }
2261#endif
2262
2263 /* Now do relocations. */
2264 for (i = 1; i < hdr->e_shnum; i++) {
2265 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2266 unsigned int info = sechdrs[i].sh_info;
2267
2268 /* Not a valid relocation section? */
2269 if (info >= hdr->e_shnum)
2270 continue;
2271
2272 /* Don't bother with non-allocated sections */
2273 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2274 continue;
2275
2276 if (sechdrs[i].sh_type == SHT_REL)
2277 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2278 else if (sechdrs[i].sh_type == SHT_RELA)
2279 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2280 mod);
2281 if (err < 0)
2282 goto cleanup;
2283 }
2284
2285 /* Find duplicate symbols */
2286 err = verify_export_symbols(mod);
2287 if (err < 0)
2288 goto cleanup;
2289
2290 /* Set up and sort exception table */
2291 mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
2292 sizeof(*mod->extable), &mod->num_exentries);
2293 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2294
2295 /* Finally, copy percpu area over. */
2296 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
2297 sechdrs[pcpuindex].sh_size);
2298
2299 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
2300
2301 if (!mod->taints) {
2302 struct _ddebug *debug;
2303 unsigned int num_debug;
2304
2305 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2306 sizeof(*debug), &num_debug);
2307 if (debug)
2308 dynamic_debug_setup(debug, num_debug);
2309 }
2310
2311 err = module_finalize(hdr, sechdrs, mod);
2312 if (err < 0)
2313 goto cleanup;
2314
2315 /* flush the icache in correct context */
2316 old_fs = get_fs();
2317 set_fs(KERNEL_DS);
2318
2319 /*
2320 * Flush the instruction cache, since we've played with text.
2321 * Do it before processing of module parameters, so the module
2322 * can provide parameter accessor functions of its own.
2323 */
2324 if (mod->module_init)
2325 flush_icache_range((unsigned long)mod->module_init,
2326 (unsigned long)mod->module_init
2327 + mod->init_size);
2328 flush_icache_range((unsigned long)mod->module_core,
2329 (unsigned long)mod->module_core + mod->core_size);
2330
2331 set_fs(old_fs);
2332
2333 mod->args = args;
2334 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2335 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2336 mod->name);
2337
2338 /* Now sew it into the lists so we can get lockdep and oops
2339 * info during argument parsing. Noone should access us, since
2340 * strong_try_module_get() will fail.
2341 * lockdep/oops can run asynchronous, so use the RCU list insertion
2342 * function to insert in a way safe to concurrent readers.
2343 * The mutex protects against concurrent writers.
2344 */
2345 list_add_rcu(&mod->list, &modules);
2346
2347 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2348 if (err < 0)
2349 goto unlink;
2350
2351 err = mod_sysfs_setup(mod, mod->kp, mod->num_kp);
2352 if (err < 0)
2353 goto unlink;
2354 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2355 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2356
2357 /* Get rid of temporary copy */
2358 vfree(hdr);
2359
2360 /* Done! */
2361 return mod;
2362
2363 unlink:
2364 /* Unlink carefully: kallsyms could be walking list. */
2365 list_del_rcu(&mod->list);
2366 synchronize_sched();
2367 module_arch_cleanup(mod);
2368 cleanup:
2369 kobject_del(&mod->mkobj.kobj);
2370 kobject_put(&mod->mkobj.kobj);
2371 free_unload:
2372 module_unload_free(mod);
2373#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
2374 free_init:
2375 percpu_modfree(mod->refptr);
2376#endif
2377 module_free(mod, mod->module_init);
2378 free_core:
2379 module_free(mod, mod->module_core);
2380 /* mod will be freed with core. Don't access it beyond this line! */
2381 free_percpu:
2382 if (percpu)
2383 percpu_modfree(percpu);
2384 free_mod:
2385 kfree(args);
2386 free_hdr:
2387 vfree(hdr);
2388 return ERR_PTR(err);
2389
2390 truncated:
2391 printk(KERN_ERR "Module len %lu truncated\n", len);
2392 err = -ENOEXEC;
2393 goto free_hdr;
2394}
2395
2396/* Call module constructors. */
2397static void do_mod_ctors(struct module *mod)
2398{
2399#ifdef CONFIG_CONSTRUCTORS
2400 unsigned long i;
2401
2402 for (i = 0; i < mod->num_ctors; i++)
2403 mod->ctors[i]();
2404#endif
2405}
2406
2407/* This is where the real work happens */
2408SYSCALL_DEFINE3(init_module, void __user *, umod,
2409 unsigned long, len, const char __user *, uargs)
2410{
2411 struct module *mod;
2412 int ret = 0;
2413
2414 /* Must have permission */
2415 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2416 return -EPERM;
2417
2418 /* Only one module load at a time, please */
2419 if (mutex_lock_interruptible(&module_mutex) != 0)
2420 return -EINTR;
2421
2422 /* Do all the hard work */
2423 mod = load_module(umod, len, uargs);
2424 if (IS_ERR(mod)) {
2425 mutex_unlock(&module_mutex);
2426 return PTR_ERR(mod);
2427 }
2428
2429 /* Drop lock so they can recurse */
2430 mutex_unlock(&module_mutex);
2431
2432 blocking_notifier_call_chain(&module_notify_list,
2433 MODULE_STATE_COMING, mod);
2434
2435 do_mod_ctors(mod);
2436 /* Start the module */
2437 if (mod->init != NULL)
2438 ret = do_one_initcall(mod->init);
2439 if (ret < 0) {
2440 /* Init routine failed: abort. Try to protect us from
2441 buggy refcounters. */
2442 mod->state = MODULE_STATE_GOING;
2443 synchronize_sched();
2444 module_put(mod);
2445 blocking_notifier_call_chain(&module_notify_list,
2446 MODULE_STATE_GOING, mod);
2447 mutex_lock(&module_mutex);
2448 free_module(mod);
2449 mutex_unlock(&module_mutex);
2450 wake_up(&module_wq);
2451 return ret;
2452 }
2453 if (ret > 0) {
2454 printk(KERN_WARNING
2455"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2456"%s: loading module anyway...\n",
2457 __func__, mod->name, ret,
2458 __func__);
2459 dump_stack();
2460 }
2461
2462 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2463 mod->state = MODULE_STATE_LIVE;
2464 wake_up(&module_wq);
2465 blocking_notifier_call_chain(&module_notify_list,
2466 MODULE_STATE_LIVE, mod);
2467
2468 /* We need to finish all async code before the module init sequence is done */
2469 async_synchronize_full();
2470
2471 mutex_lock(&module_mutex);
2472 /* Drop initial reference. */
2473 module_put(mod);
2474 trim_init_extable(mod);
2475 module_free(mod, mod->module_init);
2476 mod->module_init = NULL;
2477 mod->init_size = 0;
2478 mod->init_text_size = 0;
2479 mutex_unlock(&module_mutex);
2480
2481 return 0;
2482}
2483
2484static inline int within(unsigned long addr, void *start, unsigned long size)
2485{
2486 return ((void *)addr >= start && (void *)addr < start + size);
2487}
2488
2489#ifdef CONFIG_KALLSYMS
2490/*
2491 * This ignores the intensely annoying "mapping symbols" found
2492 * in ARM ELF files: $a, $t and $d.
2493 */
2494static inline int is_arm_mapping_symbol(const char *str)
2495{
2496 return str[0] == '$' && strchr("atd", str[1])
2497 && (str[2] == '\0' || str[2] == '.');
2498}
2499
2500static const char *get_ksymbol(struct module *mod,
2501 unsigned long addr,
2502 unsigned long *size,
2503 unsigned long *offset)
2504{
2505 unsigned int i, best = 0;
2506 unsigned long nextval;
2507
2508 /* At worse, next value is at end of module */
2509 if (within_module_init(addr, mod))
2510 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2511 else
2512 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2513
2514 /* Scan for closest preceeding symbol, and next symbol. (ELF
2515 starts real symbols at 1). */
2516 for (i = 1; i < mod->num_symtab; i++) {
2517 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2518 continue;
2519
2520 /* We ignore unnamed symbols: they're uninformative
2521 * and inserted at a whim. */
2522 if (mod->symtab[i].st_value <= addr
2523 && mod->symtab[i].st_value > mod->symtab[best].st_value
2524 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2525 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2526 best = i;
2527 if (mod->symtab[i].st_value > addr
2528 && mod->symtab[i].st_value < nextval
2529 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2530 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2531 nextval = mod->symtab[i].st_value;
2532 }
2533
2534 if (!best)
2535 return NULL;
2536
2537 if (size)
2538 *size = nextval - mod->symtab[best].st_value;
2539 if (offset)
2540 *offset = addr - mod->symtab[best].st_value;
2541 return mod->strtab + mod->symtab[best].st_name;
2542}
2543
2544/* For kallsyms to ask for address resolution. NULL means not found. Careful
2545 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2546const char *module_address_lookup(unsigned long addr,
2547 unsigned long *size,
2548 unsigned long *offset,
2549 char **modname,
2550 char *namebuf)
2551{
2552 struct module *mod;
2553 const char *ret = NULL;
2554
2555 preempt_disable();
2556 list_for_each_entry_rcu(mod, &modules, list) {
2557 if (within_module_init(addr, mod) ||
2558 within_module_core(addr, mod)) {
2559 if (modname)
2560 *modname = mod->name;
2561 ret = get_ksymbol(mod, addr, size, offset);
2562 break;
2563 }
2564 }
2565 /* Make a copy in here where it's safe */
2566 if (ret) {
2567 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2568 ret = namebuf;
2569 }
2570 preempt_enable();
2571 return ret;
2572}
2573
2574int lookup_module_symbol_name(unsigned long addr, char *symname)
2575{
2576 struct module *mod;
2577
2578 preempt_disable();
2579 list_for_each_entry_rcu(mod, &modules, list) {
2580 if (within_module_init(addr, mod) ||
2581 within_module_core(addr, mod)) {
2582 const char *sym;
2583
2584 sym = get_ksymbol(mod, addr, NULL, NULL);
2585 if (!sym)
2586 goto out;
2587 strlcpy(symname, sym, KSYM_NAME_LEN);
2588 preempt_enable();
2589 return 0;
2590 }
2591 }
2592out:
2593 preempt_enable();
2594 return -ERANGE;
2595}
2596
2597int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2598 unsigned long *offset, char *modname, char *name)
2599{
2600 struct module *mod;
2601
2602 preempt_disable();
2603 list_for_each_entry_rcu(mod, &modules, list) {
2604 if (within_module_init(addr, mod) ||
2605 within_module_core(addr, mod)) {
2606 const char *sym;
2607
2608 sym = get_ksymbol(mod, addr, size, offset);
2609 if (!sym)
2610 goto out;
2611 if (modname)
2612 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2613 if (name)
2614 strlcpy(name, sym, KSYM_NAME_LEN);
2615 preempt_enable();
2616 return 0;
2617 }
2618 }
2619out:
2620 preempt_enable();
2621 return -ERANGE;
2622}
2623
2624int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2625 char *name, char *module_name, int *exported)
2626{
2627 struct module *mod;
2628
2629 preempt_disable();
2630 list_for_each_entry_rcu(mod, &modules, list) {
2631 if (symnum < mod->num_symtab) {
2632 *value = mod->symtab[symnum].st_value;
2633 *type = mod->symtab[symnum].st_info;
2634 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2635 KSYM_NAME_LEN);
2636 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2637 *exported = is_exported(name, *value, mod);
2638 preempt_enable();
2639 return 0;
2640 }
2641 symnum -= mod->num_symtab;
2642 }
2643 preempt_enable();
2644 return -ERANGE;
2645}
2646
2647static unsigned long mod_find_symname(struct module *mod, const char *name)
2648{
2649 unsigned int i;
2650
2651 for (i = 0; i < mod->num_symtab; i++)
2652 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2653 mod->symtab[i].st_info != 'U')
2654 return mod->symtab[i].st_value;
2655 return 0;
2656}
2657
2658/* Look for this name: can be of form module:name. */
2659unsigned long module_kallsyms_lookup_name(const char *name)
2660{
2661 struct module *mod;
2662 char *colon;
2663 unsigned long ret = 0;
2664
2665 /* Don't lock: we're in enough trouble already. */
2666 preempt_disable();
2667 if ((colon = strchr(name, ':')) != NULL) {
2668 *colon = '\0';
2669 if ((mod = find_module(name)) != NULL)
2670 ret = mod_find_symname(mod, colon+1);
2671 *colon = ':';
2672 } else {
2673 list_for_each_entry_rcu(mod, &modules, list)
2674 if ((ret = mod_find_symname(mod, name)) != 0)
2675 break;
2676 }
2677 preempt_enable();
2678 return ret;
2679}
2680
2681int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
2682 struct module *, unsigned long),
2683 void *data)
2684{
2685 struct module *mod;
2686 unsigned int i;
2687 int ret;
2688
2689 list_for_each_entry(mod, &modules, list) {
2690 for (i = 0; i < mod->num_symtab; i++) {
2691 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
2692 mod, mod->symtab[i].st_value);
2693 if (ret != 0)
2694 return ret;
2695 }
2696 }
2697 return 0;
2698}
2699#endif /* CONFIG_KALLSYMS */
2700
2701static char *module_flags(struct module *mod, char *buf)
2702{
2703 int bx = 0;
2704
2705 if (mod->taints ||
2706 mod->state == MODULE_STATE_GOING ||
2707 mod->state == MODULE_STATE_COMING) {
2708 buf[bx++] = '(';
2709 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2710 buf[bx++] = 'P';
2711 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2712 buf[bx++] = 'F';
2713 if (mod->taints & (1 << TAINT_CRAP))
2714 buf[bx++] = 'C';
2715 /*
2716 * TAINT_FORCED_RMMOD: could be added.
2717 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2718 * apply to modules.
2719 */
2720
2721 /* Show a - for module-is-being-unloaded */
2722 if (mod->state == MODULE_STATE_GOING)
2723 buf[bx++] = '-';
2724 /* Show a + for module-is-being-loaded */
2725 if (mod->state == MODULE_STATE_COMING)
2726 buf[bx++] = '+';
2727 buf[bx++] = ')';
2728 }
2729 buf[bx] = '\0';
2730
2731 return buf;
2732}
2733
2734#ifdef CONFIG_PROC_FS
2735/* Called by the /proc file system to return a list of modules. */
2736static void *m_start(struct seq_file *m, loff_t *pos)
2737{
2738 mutex_lock(&module_mutex);
2739 return seq_list_start(&modules, *pos);
2740}
2741
2742static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2743{
2744 return seq_list_next(p, &modules, pos);
2745}
2746
2747static void m_stop(struct seq_file *m, void *p)
2748{
2749 mutex_unlock(&module_mutex);
2750}
2751
2752static int m_show(struct seq_file *m, void *p)
2753{
2754 struct module *mod = list_entry(p, struct module, list);
2755 char buf[8];
2756
2757 seq_printf(m, "%s %u",
2758 mod->name, mod->init_size + mod->core_size);
2759 print_unload_info(m, mod);
2760
2761 /* Informative for users. */
2762 seq_printf(m, " %s",
2763 mod->state == MODULE_STATE_GOING ? "Unloading":
2764 mod->state == MODULE_STATE_COMING ? "Loading":
2765 "Live");
2766 /* Used by oprofile and other similar tools. */
2767 seq_printf(m, " 0x%p", mod->module_core);
2768
2769 /* Taints info */
2770 if (mod->taints)
2771 seq_printf(m, " %s", module_flags(mod, buf));
2772
2773 seq_printf(m, "\n");
2774 return 0;
2775}
2776
2777/* Format: modulename size refcount deps address
2778
2779 Where refcount is a number or -, and deps is a comma-separated list
2780 of depends or -.
2781*/
2782static const struct seq_operations modules_op = {
2783 .start = m_start,
2784 .next = m_next,
2785 .stop = m_stop,
2786 .show = m_show
2787};
2788
2789static int modules_open(struct inode *inode, struct file *file)
2790{
2791 return seq_open(file, &modules_op);
2792}
2793
2794static const struct file_operations proc_modules_operations = {
2795 .open = modules_open,
2796 .read = seq_read,
2797 .llseek = seq_lseek,
2798 .release = seq_release,
2799};
2800
2801static int __init proc_modules_init(void)
2802{
2803 proc_create("modules", 0, NULL, &proc_modules_operations);
2804 return 0;
2805}
2806module_init(proc_modules_init);
2807#endif
2808
2809/* Given an address, look for it in the module exception tables. */
2810const struct exception_table_entry *search_module_extables(unsigned long addr)
2811{
2812 const struct exception_table_entry *e = NULL;
2813 struct module *mod;
2814
2815 preempt_disable();
2816 list_for_each_entry_rcu(mod, &modules, list) {
2817 if (mod->num_exentries == 0)
2818 continue;
2819
2820 e = search_extable(mod->extable,
2821 mod->extable + mod->num_exentries - 1,
2822 addr);
2823 if (e)
2824 break;
2825 }
2826 preempt_enable();
2827
2828 /* Now, if we found one, we are running inside it now, hence
2829 we cannot unload the module, hence no refcnt needed. */
2830 return e;
2831}
2832
2833/*
2834 * is_module_address - is this address inside a module?
2835 * @addr: the address to check.
2836 *
2837 * See is_module_text_address() if you simply want to see if the address
2838 * is code (not data).
2839 */
2840bool is_module_address(unsigned long addr)
2841{
2842 bool ret;
2843
2844 preempt_disable();
2845 ret = __module_address(addr) != NULL;
2846 preempt_enable();
2847
2848 return ret;
2849}
2850
2851/*
2852 * __module_address - get the module which contains an address.
2853 * @addr: the address.
2854 *
2855 * Must be called with preempt disabled or module mutex held so that
2856 * module doesn't get freed during this.
2857 */
2858struct module *__module_address(unsigned long addr)
2859{
2860 struct module *mod;
2861
2862 if (addr < module_addr_min || addr > module_addr_max)
2863 return NULL;
2864
2865 list_for_each_entry_rcu(mod, &modules, list)
2866 if (within_module_core(addr, mod)
2867 || within_module_init(addr, mod))
2868 return mod;
2869 return NULL;
2870}
2871EXPORT_SYMBOL_GPL(__module_address);
2872
2873/*
2874 * is_module_text_address - is this address inside module code?
2875 * @addr: the address to check.
2876 *
2877 * See is_module_address() if you simply want to see if the address is
2878 * anywhere in a module. See kernel_text_address() for testing if an
2879 * address corresponds to kernel or module code.
2880 */
2881bool is_module_text_address(unsigned long addr)
2882{
2883 bool ret;
2884
2885 preempt_disable();
2886 ret = __module_text_address(addr) != NULL;
2887 preempt_enable();
2888
2889 return ret;
2890}
2891
2892/*
2893 * __module_text_address - get the module whose code contains an address.
2894 * @addr: the address.
2895 *
2896 * Must be called with preempt disabled or module mutex held so that
2897 * module doesn't get freed during this.
2898 */
2899struct module *__module_text_address(unsigned long addr)
2900{
2901 struct module *mod = __module_address(addr);
2902 if (mod) {
2903 /* Make sure it's within the text section. */
2904 if (!within(addr, mod->module_init, mod->init_text_size)
2905 && !within(addr, mod->module_core, mod->core_text_size))
2906 mod = NULL;
2907 }
2908 return mod;
2909}
2910EXPORT_SYMBOL_GPL(__module_text_address);
2911
2912/* Don't grab lock, we're oopsing. */
2913void print_modules(void)
2914{
2915 struct module *mod;
2916 char buf[8];
2917
2918 printk(KERN_DEFAULT "Modules linked in:");
2919 /* Most callers should already have preempt disabled, but make sure */
2920 preempt_disable();
2921 list_for_each_entry_rcu(mod, &modules, list)
2922 printk(" %s%s", mod->name, module_flags(mod, buf));
2923 preempt_enable();
2924 if (last_unloaded_module[0])
2925 printk(" [last unloaded: %s]", last_unloaded_module);
2926 printk("\n");
2927}
2928
2929#ifdef CONFIG_MODVERSIONS
2930/* Generate the signature for all relevant module structures here.
2931 * If these change, we don't want to try to parse the module. */
2932void module_layout(struct module *mod,
2933 struct modversion_info *ver,
2934 struct kernel_param *kp,
2935 struct kernel_symbol *ks,
2936 struct marker *marker,
2937 struct tracepoint *tp)
2938{
2939}
2940EXPORT_SYMBOL(module_layout);
2941#endif
2942
2943#ifdef CONFIG_MARKERS
2944void module_update_markers(void)
2945{
2946 struct module *mod;
2947
2948 mutex_lock(&module_mutex);
2949 list_for_each_entry(mod, &modules, list)
2950 if (!mod->taints)
2951 marker_update_probe_range(mod->markers,
2952 mod->markers + mod->num_markers);
2953 mutex_unlock(&module_mutex);
2954}
2955#endif
2956
2957#ifdef CONFIG_TRACEPOINTS
2958void module_update_tracepoints(void)
2959{
2960 struct module *mod;
2961
2962 mutex_lock(&module_mutex);
2963 list_for_each_entry(mod, &modules, list)
2964 if (!mod->taints)
2965 tracepoint_update_probe_range(mod->tracepoints,
2966 mod->tracepoints + mod->num_tracepoints);
2967 mutex_unlock(&module_mutex);
2968}
2969
2970/*
2971 * Returns 0 if current not found.
2972 * Returns 1 if current found.
2973 */
2974int module_get_iter_tracepoints(struct tracepoint_iter *iter)
2975{
2976 struct module *iter_mod;
2977 int found = 0;
2978
2979 mutex_lock(&module_mutex);
2980 list_for_each_entry(iter_mod, &modules, list) {
2981 if (!iter_mod->taints) {
2982 /*
2983 * Sorted module list
2984 */
2985 if (iter_mod < iter->module)
2986 continue;
2987 else if (iter_mod > iter->module)
2988 iter->tracepoint = NULL;
2989 found = tracepoint_get_iter_range(&iter->tracepoint,
2990 iter_mod->tracepoints,
2991 iter_mod->tracepoints
2992 + iter_mod->num_tracepoints);
2993 if (found) {
2994 iter->module = iter_mod;
2995 break;
2996 }
2997 }
2998 }
2999 mutex_unlock(&module_mutex);
3000 return found;
3001}
3002#endif