projects/linux·blob v2.6.33-rc1 · refs

3016 lines · 77.4 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 <asm/mmu_context.h>
51#include <linux/license.h>
52#include <asm/sections.h>
53#include <linux/tracepoint.h>
54#include <linux/ftrace.h>
55#include <linux/async.h>
56#include <linux/percpu.h>
57#include <linux/kmemleak.h>
58
59#define CREATE_TRACE_POINTS
60#include <trace/events/module.h>
61
62EXPORT_TRACEPOINT_SYMBOL(module_get);
63
64#if 0
65#define DEBUGP printk
66#else
67#define DEBUGP(fmt , a...)
68#endif
69
70#ifndef ARCH_SHF_SMALL
71#define ARCH_SHF_SMALL 0
72#endif
73
74/* If this is set, the section belongs in the init part of the module */
75#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
76
77/* List of modules, protected by module_mutex or preempt_disable
78 * (delete uses stop_machine/add uses RCU list operations). */
79DEFINE_MUTEX(module_mutex);
80EXPORT_SYMBOL_GPL(module_mutex);
81static LIST_HEAD(modules);
82
83/* Block module loading/unloading? */
84int modules_disabled = 0;
85
86/* Waiting for a module to finish initializing? */
87static DECLARE_WAIT_QUEUE_HEAD(module_wq);
88
89static BLOCKING_NOTIFIER_HEAD(module_notify_list);
90
91/* Bounds of module allocation, for speeding __module_address */
92static unsigned long module_addr_min = -1UL, module_addr_max = 0;
93
94int register_module_notifier(struct notifier_block * nb)
95{
96 return blocking_notifier_chain_register(&module_notify_list, nb);
97}
98EXPORT_SYMBOL(register_module_notifier);
99
100int unregister_module_notifier(struct notifier_block * nb)
101{
102 return blocking_notifier_chain_unregister(&module_notify_list, nb);
103}
104EXPORT_SYMBOL(unregister_module_notifier);
105
106/* We require a truly strong try_module_get(): 0 means failure due to
107 ongoing or failed initialization etc. */
108static inline int strong_try_module_get(struct module *mod)
109{
110 if (mod && mod->state == MODULE_STATE_COMING)
111 return -EBUSY;
112 if (try_module_get(mod))
113 return 0;
114 else
115 return -ENOENT;
116}
117
118static inline void add_taint_module(struct module *mod, unsigned flag)
119{
120 add_taint(flag);
121 mod->taints |= (1U << flag);
122}
123
124/*
125 * A thread that wants to hold a reference to a module only while it
126 * is running can call this to safely exit. nfsd and lockd use this.
127 */
128void __module_put_and_exit(struct module *mod, long code)
129{
130 module_put(mod);
131 do_exit(code);
132}
133EXPORT_SYMBOL(__module_put_and_exit);
134
135/* Find a module section: 0 means not found. */
136static unsigned int find_sec(Elf_Ehdr *hdr,
137 Elf_Shdr *sechdrs,
138 const char *secstrings,
139 const char *name)
140{
141 unsigned int i;
142
143 for (i = 1; i < hdr->e_shnum; i++)
144 /* Alloc bit cleared means "ignore it." */
145 if ((sechdrs[i].sh_flags & SHF_ALLOC)
146 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
147 return i;
148 return 0;
149}
150
151/* Find a module section, or NULL. */
152static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
153 const char *secstrings, const char *name)
154{
155 /* Section 0 has sh_addr 0. */
156 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
157}
158
159/* Find a module section, or NULL. Fill in number of "objects" in section. */
160static void *section_objs(Elf_Ehdr *hdr,
161 Elf_Shdr *sechdrs,
162 const char *secstrings,
163 const char *name,
164 size_t object_size,
165 unsigned int *num)
166{
167 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
168
169 /* Section 0 has sh_addr 0 and sh_size 0. */
170 *num = sechdrs[sec].sh_size / object_size;
171 return (void *)sechdrs[sec].sh_addr;
172}
173
174/* Provided by the linker */
175extern const struct kernel_symbol __start___ksymtab[];
176extern const struct kernel_symbol __stop___ksymtab[];
177extern const struct kernel_symbol __start___ksymtab_gpl[];
178extern const struct kernel_symbol __stop___ksymtab_gpl[];
179extern const struct kernel_symbol __start___ksymtab_gpl_future[];
180extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
181extern const struct kernel_symbol __start___ksymtab_gpl_future[];
182extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
183extern const unsigned long __start___kcrctab[];
184extern const unsigned long __start___kcrctab_gpl[];
185extern const unsigned long __start___kcrctab_gpl_future[];
186#ifdef CONFIG_UNUSED_SYMBOLS
187extern const struct kernel_symbol __start___ksymtab_unused[];
188extern const struct kernel_symbol __stop___ksymtab_unused[];
189extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
190extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
191extern const unsigned long __start___kcrctab_unused[];
192extern const unsigned long __start___kcrctab_unused_gpl[];
193#endif
194
195#ifndef CONFIG_MODVERSIONS
196#define symversion(base, idx) NULL
197#else
198#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
199#endif
200
201static bool each_symbol_in_section(const struct symsearch *arr,
202 unsigned int arrsize,
203 struct module *owner,
204 bool (*fn)(const struct symsearch *syms,
205 struct module *owner,
206 unsigned int symnum, void *data),
207 void *data)
208{
209 unsigned int i, j;
210
211 for (j = 0; j < arrsize; j++) {
212 for (i = 0; i < arr[j].stop - arr[j].start; i++)
213 if (fn(&arr[j], owner, i, data))
214 return true;
215 }
216
217 return false;
218}
219
220/* Returns true as soon as fn returns true, otherwise false. */
221bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
222 unsigned int symnum, void *data), void *data)
223{
224 struct module *mod;
225 const struct symsearch arr[] = {
226 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
227 NOT_GPL_ONLY, false },
228 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
229 __start___kcrctab_gpl,
230 GPL_ONLY, false },
231 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
232 __start___kcrctab_gpl_future,
233 WILL_BE_GPL_ONLY, false },
234#ifdef CONFIG_UNUSED_SYMBOLS
235 { __start___ksymtab_unused, __stop___ksymtab_unused,
236 __start___kcrctab_unused,
237 NOT_GPL_ONLY, true },
238 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
239 __start___kcrctab_unused_gpl,
240 GPL_ONLY, true },
241#endif
242 };
243
244 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
245 return true;
246
247 list_for_each_entry_rcu(mod, &modules, list) {
248 struct symsearch arr[] = {
249 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
250 NOT_GPL_ONLY, false },
251 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
252 mod->gpl_crcs,
253 GPL_ONLY, false },
254 { mod->gpl_future_syms,
255 mod->gpl_future_syms + mod->num_gpl_future_syms,
256 mod->gpl_future_crcs,
257 WILL_BE_GPL_ONLY, false },
258#ifdef CONFIG_UNUSED_SYMBOLS
259 { mod->unused_syms,
260 mod->unused_syms + mod->num_unused_syms,
261 mod->unused_crcs,
262 NOT_GPL_ONLY, true },
263 { mod->unused_gpl_syms,
264 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
265 mod->unused_gpl_crcs,
266 GPL_ONLY, true },
267#endif
268 };
269
270 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
271 return true;
272 }
273 return false;
274}
275EXPORT_SYMBOL_GPL(each_symbol);
276
277struct find_symbol_arg {
278 /* Input */
279 const char *name;
280 bool gplok;
281 bool warn;
282
283 /* Output */
284 struct module *owner;
285 const unsigned long *crc;
286 const struct kernel_symbol *sym;
287};
288
289static bool find_symbol_in_section(const struct symsearch *syms,
290 struct module *owner,
291 unsigned int symnum, void *data)
292{
293 struct find_symbol_arg *fsa = data;
294
295 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
296 return false;
297
298 if (!fsa->gplok) {
299 if (syms->licence == GPL_ONLY)
300 return false;
301 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
302 printk(KERN_WARNING "Symbol %s is being used "
303 "by a non-GPL module, which will not "
304 "be allowed in the future\n", fsa->name);
305 printk(KERN_WARNING "Please see the file "
306 "Documentation/feature-removal-schedule.txt "
307 "in the kernel source tree for more details.\n");
308 }
309 }
310
311#ifdef CONFIG_UNUSED_SYMBOLS
312 if (syms->unused && fsa->warn) {
313 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
314 "however this module is using it.\n", fsa->name);
315 printk(KERN_WARNING
316 "This symbol will go away in the future.\n");
317 printk(KERN_WARNING
318 "Please evalute if this is the right api to use and if "
319 "it really is, submit a report the linux kernel "
320 "mailinglist together with submitting your code for "
321 "inclusion.\n");
322 }
323#endif
324
325 fsa->owner = owner;
326 fsa->crc = symversion(syms->crcs, symnum);
327 fsa->sym = &syms->start[symnum];
328 return true;
329}
330
331/* Find a symbol and return it, along with, (optional) crc and
332 * (optional) module which owns it */
333const struct kernel_symbol *find_symbol(const char *name,
334 struct module **owner,
335 const unsigned long **crc,
336 bool gplok,
337 bool warn)
338{
339 struct find_symbol_arg fsa;
340
341 fsa.name = name;
342 fsa.gplok = gplok;
343 fsa.warn = warn;
344
345 if (each_symbol(find_symbol_in_section, &fsa)) {
346 if (owner)
347 *owner = fsa.owner;
348 if (crc)
349 *crc = fsa.crc;
350 return fsa.sym;
351 }
352
353 DEBUGP("Failed to find symbol %s\n", name);
354 return NULL;
355}
356EXPORT_SYMBOL_GPL(find_symbol);
357
358/* Search for module by name: must hold module_mutex. */
359struct module *find_module(const char *name)
360{
361 struct module *mod;
362
363 list_for_each_entry(mod, &modules, list) {
364 if (strcmp(mod->name, name) == 0)
365 return mod;
366 }
367 return NULL;
368}
369EXPORT_SYMBOL_GPL(find_module);
370
371#ifdef CONFIG_SMP
372
373static void *percpu_modalloc(unsigned long size, unsigned long align,
374 const char *name)
375{
376 void *ptr;
377
378 if (align > PAGE_SIZE) {
379 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
380 name, align, PAGE_SIZE);
381 align = PAGE_SIZE;
382 }
383
384 ptr = __alloc_reserved_percpu(size, align);
385 if (!ptr)
386 printk(KERN_WARNING
387 "Could not allocate %lu bytes percpu data\n", size);
388 return ptr;
389}
390
391static void percpu_modfree(void *freeme)
392{
393 free_percpu(freeme);
394}
395
396static unsigned int find_pcpusec(Elf_Ehdr *hdr,
397 Elf_Shdr *sechdrs,
398 const char *secstrings)
399{
400 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
401}
402
403static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
404{
405 int cpu;
406
407 for_each_possible_cpu(cpu)
408 memcpy(pcpudest + per_cpu_offset(cpu), from, size);
409}
410
411#else /* ... !CONFIG_SMP */
412
413static inline void *percpu_modalloc(unsigned long size, unsigned long align,
414 const char *name)
415{
416 return NULL;
417}
418static inline void percpu_modfree(void *pcpuptr)
419{
420 BUG();
421}
422static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
423 Elf_Shdr *sechdrs,
424 const char *secstrings)
425{
426 return 0;
427}
428static inline void percpu_modcopy(void *pcpudst, const void *src,
429 unsigned long size)
430{
431 /* pcpusec should be 0, and size of that section should be 0. */
432 BUG_ON(size != 0);
433}
434
435#endif /* CONFIG_SMP */
436
437#define MODINFO_ATTR(field) \
438static void setup_modinfo_##field(struct module *mod, const char *s) \
439{ \
440 mod->field = kstrdup(s, GFP_KERNEL); \
441} \
442static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
443 struct module *mod, char *buffer) \
444{ \
445 return sprintf(buffer, "%s\n", mod->field); \
446} \
447static int modinfo_##field##_exists(struct module *mod) \
448{ \
449 return mod->field != NULL; \
450} \
451static void free_modinfo_##field(struct module *mod) \
452{ \
453 kfree(mod->field); \
454 mod->field = NULL; \
455} \
456static struct module_attribute modinfo_##field = { \
457 .attr = { .name = __stringify(field), .mode = 0444 }, \
458 .show = show_modinfo_##field, \
459 .setup = setup_modinfo_##field, \
460 .test = modinfo_##field##_exists, \
461 .free = free_modinfo_##field, \
462};
463
464MODINFO_ATTR(version);
465MODINFO_ATTR(srcversion);
466
467static char last_unloaded_module[MODULE_NAME_LEN+1];
468
469#ifdef CONFIG_MODULE_UNLOAD
470/* Init the unload section of the module. */
471static void module_unload_init(struct module *mod)
472{
473 int cpu;
474
475 INIT_LIST_HEAD(&mod->modules_which_use_me);
476 for_each_possible_cpu(cpu)
477 local_set(__module_ref_addr(mod, cpu), 0);
478 /* Hold reference count during initialization. */
479 local_set(__module_ref_addr(mod, raw_smp_processor_id()), 1);
480 /* Backwards compatibility macros put refcount during init. */
481 mod->waiter = current;
482}
483
484/* modules using other modules */
485struct module_use
486{
487 struct list_head list;
488 struct module *module_which_uses;
489};
490
491/* Does a already use b? */
492static int already_uses(struct module *a, struct module *b)
493{
494 struct module_use *use;
495
496 list_for_each_entry(use, &b->modules_which_use_me, list) {
497 if (use->module_which_uses == a) {
498 DEBUGP("%s uses %s!\n", a->name, b->name);
499 return 1;
500 }
501 }
502 DEBUGP("%s does not use %s!\n", a->name, b->name);
503 return 0;
504}
505
506/* Module a uses b */
507int use_module(struct module *a, struct module *b)
508{
509 struct module_use *use;
510 int no_warn, err;
511
512 if (b == NULL || already_uses(a, b)) return 1;
513
514 /* If we're interrupted or time out, we fail. */
515 if (wait_event_interruptible_timeout(
516 module_wq, (err = strong_try_module_get(b)) != -EBUSY,
517 30 * HZ) <= 0) {
518 printk("%s: gave up waiting for init of module %s.\n",
519 a->name, b->name);
520 return 0;
521 }
522
523 /* If strong_try_module_get() returned a different error, we fail. */
524 if (err)
525 return 0;
526
527 DEBUGP("Allocating new usage for %s.\n", a->name);
528 use = kmalloc(sizeof(*use), GFP_ATOMIC);
529 if (!use) {
530 printk("%s: out of memory loading\n", a->name);
531 module_put(b);
532 return 0;
533 }
534
535 use->module_which_uses = a;
536 list_add(&use->list, &b->modules_which_use_me);
537 no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
538 return 1;
539}
540EXPORT_SYMBOL_GPL(use_module);
541
542/* Clear the unload stuff of the module. */
543static void module_unload_free(struct module *mod)
544{
545 struct module *i;
546
547 list_for_each_entry(i, &modules, list) {
548 struct module_use *use;
549
550 list_for_each_entry(use, &i->modules_which_use_me, list) {
551 if (use->module_which_uses == mod) {
552 DEBUGP("%s unusing %s\n", mod->name, i->name);
553 module_put(i);
554 list_del(&use->list);
555 kfree(use);
556 sysfs_remove_link(i->holders_dir, mod->name);
557 /* There can be at most one match. */
558 break;
559 }
560 }
561 }
562}
563
564#ifdef CONFIG_MODULE_FORCE_UNLOAD
565static inline int try_force_unload(unsigned int flags)
566{
567 int ret = (flags & O_TRUNC);
568 if (ret)
569 add_taint(TAINT_FORCED_RMMOD);
570 return ret;
571}
572#else
573static inline int try_force_unload(unsigned int flags)
574{
575 return 0;
576}
577#endif /* CONFIG_MODULE_FORCE_UNLOAD */
578
579struct stopref
580{
581 struct module *mod;
582 int flags;
583 int *forced;
584};
585
586/* Whole machine is stopped with interrupts off when this runs. */
587static int __try_stop_module(void *_sref)
588{
589 struct stopref *sref = _sref;
590
591 /* If it's not unused, quit unless we're forcing. */
592 if (module_refcount(sref->mod) != 0) {
593 if (!(*sref->forced = try_force_unload(sref->flags)))
594 return -EWOULDBLOCK;
595 }
596
597 /* Mark it as dying. */
598 sref->mod->state = MODULE_STATE_GOING;
599 return 0;
600}
601
602static int try_stop_module(struct module *mod, int flags, int *forced)
603{
604 if (flags & O_NONBLOCK) {
605 struct stopref sref = { mod, flags, forced };
606
607 return stop_machine(__try_stop_module, &sref, NULL);
608 } else {
609 /* We don't need to stop the machine for this. */
610 mod->state = MODULE_STATE_GOING;
611 synchronize_sched();
612 return 0;
613 }
614}
615
616unsigned int module_refcount(struct module *mod)
617{
618 unsigned int total = 0;
619 int cpu;
620
621 for_each_possible_cpu(cpu)
622 total += local_read(__module_ref_addr(mod, cpu));
623 return total;
624}
625EXPORT_SYMBOL(module_refcount);
626
627/* This exists whether we can unload or not */
628static void free_module(struct module *mod);
629
630static void wait_for_zero_refcount(struct module *mod)
631{
632 /* Since we might sleep for some time, release the mutex first */
633 mutex_unlock(&module_mutex);
634 for (;;) {
635 DEBUGP("Looking at refcount...\n");
636 set_current_state(TASK_UNINTERRUPTIBLE);
637 if (module_refcount(mod) == 0)
638 break;
639 schedule();
640 }
641 current->state = TASK_RUNNING;
642 mutex_lock(&module_mutex);
643}
644
645SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
646 unsigned int, flags)
647{
648 struct module *mod;
649 char name[MODULE_NAME_LEN];
650 int ret, forced = 0;
651
652 if (!capable(CAP_SYS_MODULE) || modules_disabled)
653 return -EPERM;
654
655 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
656 return -EFAULT;
657 name[MODULE_NAME_LEN-1] = '\0';
658
659 /* Create stop_machine threads since free_module relies on
660 * a non-failing stop_machine call. */
661 ret = stop_machine_create();
662 if (ret)
663 return ret;
664
665 if (mutex_lock_interruptible(&module_mutex) != 0) {
666 ret = -EINTR;
667 goto out_stop;
668 }
669
670 mod = find_module(name);
671 if (!mod) {
672 ret = -ENOENT;
673 goto out;
674 }
675
676 if (!list_empty(&mod->modules_which_use_me)) {
677 /* Other modules depend on us: get rid of them first. */
678 ret = -EWOULDBLOCK;
679 goto out;
680 }
681
682 /* Doing init or already dying? */
683 if (mod->state != MODULE_STATE_LIVE) {
684 /* FIXME: if (force), slam module count and wake up
685 waiter --RR */
686 DEBUGP("%s already dying\n", mod->name);
687 ret = -EBUSY;
688 goto out;
689 }
690
691 /* If it has an init func, it must have an exit func to unload */
692 if (mod->init && !mod->exit) {
693 forced = try_force_unload(flags);
694 if (!forced) {
695 /* This module can't be removed */
696 ret = -EBUSY;
697 goto out;
698 }
699 }
700
701 /* Set this up before setting mod->state */
702 mod->waiter = current;
703
704 /* Stop the machine so refcounts can't move and disable module. */
705 ret = try_stop_module(mod, flags, &forced);
706 if (ret != 0)
707 goto out;
708
709 /* Never wait if forced. */
710 if (!forced && module_refcount(mod) != 0)
711 wait_for_zero_refcount(mod);
712
713 mutex_unlock(&module_mutex);
714 /* Final destruction now noone is using it. */
715 if (mod->exit != NULL)
716 mod->exit();
717 blocking_notifier_call_chain(&module_notify_list,
718 MODULE_STATE_GOING, mod);
719 async_synchronize_full();
720 mutex_lock(&module_mutex);
721 /* Store the name of the last unloaded module for diagnostic purposes */
722 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
723 ddebug_remove_module(mod->name);
724 free_module(mod);
725
726 out:
727 mutex_unlock(&module_mutex);
728out_stop:
729 stop_machine_destroy();
730 return ret;
731}
732
733static inline void print_unload_info(struct seq_file *m, struct module *mod)
734{
735 struct module_use *use;
736 int printed_something = 0;
737
738 seq_printf(m, " %u ", module_refcount(mod));
739
740 /* Always include a trailing , so userspace can differentiate
741 between this and the old multi-field proc format. */
742 list_for_each_entry(use, &mod->modules_which_use_me, list) {
743 printed_something = 1;
744 seq_printf(m, "%s,", use->module_which_uses->name);
745 }
746
747 if (mod->init != NULL && mod->exit == NULL) {
748 printed_something = 1;
749 seq_printf(m, "[permanent],");
750 }
751
752 if (!printed_something)
753 seq_printf(m, "-");
754}
755
756void __symbol_put(const char *symbol)
757{
758 struct module *owner;
759
760 preempt_disable();
761 if (!find_symbol(symbol, &owner, NULL, true, false))
762 BUG();
763 module_put(owner);
764 preempt_enable();
765}
766EXPORT_SYMBOL(__symbol_put);
767
768/* Note this assumes addr is a function, which it currently always is. */
769void symbol_put_addr(void *addr)
770{
771 struct module *modaddr;
772 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
773
774 if (core_kernel_text(a))
775 return;
776
777 /* module_text_address is safe here: we're supposed to have reference
778 * to module from symbol_get, so it can't go away. */
779 modaddr = __module_text_address(a);
780 BUG_ON(!modaddr);
781 module_put(modaddr);
782}
783EXPORT_SYMBOL_GPL(symbol_put_addr);
784
785static ssize_t show_refcnt(struct module_attribute *mattr,
786 struct module *mod, char *buffer)
787{
788 return sprintf(buffer, "%u\n", module_refcount(mod));
789}
790
791static struct module_attribute refcnt = {
792 .attr = { .name = "refcnt", .mode = 0444 },
793 .show = show_refcnt,
794};
795
796void module_put(struct module *module)
797{
798 if (module) {
799 unsigned int cpu = get_cpu();
800 local_dec(__module_ref_addr(module, cpu));
801 trace_module_put(module, _RET_IP_,
802 local_read(__module_ref_addr(module, cpu)));
803 /* Maybe they're waiting for us to drop reference? */
804 if (unlikely(!module_is_live(module)))
805 wake_up_process(module->waiter);
806 put_cpu();
807 }
808}
809EXPORT_SYMBOL(module_put);
810
811#else /* !CONFIG_MODULE_UNLOAD */
812static inline void print_unload_info(struct seq_file *m, struct module *mod)
813{
814 /* We don't know the usage count, or what modules are using. */
815 seq_printf(m, " - -");
816}
817
818static inline void module_unload_free(struct module *mod)
819{
820}
821
822int use_module(struct module *a, struct module *b)
823{
824 return strong_try_module_get(b) == 0;
825}
826EXPORT_SYMBOL_GPL(use_module);
827
828static inline void module_unload_init(struct module *mod)
829{
830}
831#endif /* CONFIG_MODULE_UNLOAD */
832
833static ssize_t show_initstate(struct module_attribute *mattr,
834 struct module *mod, char *buffer)
835{
836 const char *state = "unknown";
837
838 switch (mod->state) {
839 case MODULE_STATE_LIVE:
840 state = "live";
841 break;
842 case MODULE_STATE_COMING:
843 state = "coming";
844 break;
845 case MODULE_STATE_GOING:
846 state = "going";
847 break;
848 }
849 return sprintf(buffer, "%s\n", state);
850}
851
852static struct module_attribute initstate = {
853 .attr = { .name = "initstate", .mode = 0444 },
854 .show = show_initstate,
855};
856
857static struct module_attribute *modinfo_attrs[] = {
858 &modinfo_version,
859 &modinfo_srcversion,
860 &initstate,
861#ifdef CONFIG_MODULE_UNLOAD
862 &refcnt,
863#endif
864 NULL,
865};
866
867static const char vermagic[] = VERMAGIC_STRING;
868
869static int try_to_force_load(struct module *mod, const char *reason)
870{
871#ifdef CONFIG_MODULE_FORCE_LOAD
872 if (!test_taint(TAINT_FORCED_MODULE))
873 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
874 mod->name, reason);
875 add_taint_module(mod, TAINT_FORCED_MODULE);
876 return 0;
877#else
878 return -ENOEXEC;
879#endif
880}
881
882#ifdef CONFIG_MODVERSIONS
883/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
884static unsigned long maybe_relocated(unsigned long crc,
885 const struct module *crc_owner)
886{
887#ifdef ARCH_RELOCATES_KCRCTAB
888 if (crc_owner == NULL)
889 return crc - (unsigned long)reloc_start;
890#endif
891 return crc;
892}
893
894static int check_version(Elf_Shdr *sechdrs,
895 unsigned int versindex,
896 const char *symname,
897 struct module *mod,
898 const unsigned long *crc,
899 const struct module *crc_owner)
900{
901 unsigned int i, num_versions;
902 struct modversion_info *versions;
903
904 /* Exporting module didn't supply crcs? OK, we're already tainted. */
905 if (!crc)
906 return 1;
907
908 /* No versions at all? modprobe --force does this. */
909 if (versindex == 0)
910 return try_to_force_load(mod, symname) == 0;
911
912 versions = (void *) sechdrs[versindex].sh_addr;
913 num_versions = sechdrs[versindex].sh_size
914 / sizeof(struct modversion_info);
915
916 for (i = 0; i < num_versions; i++) {
917 if (strcmp(versions[i].name, symname) != 0)
918 continue;
919
920 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
921 return 1;
922 DEBUGP("Found checksum %lX vs module %lX\n",
923 maybe_relocated(*crc, crc_owner), versions[i].crc);
924 goto bad_version;
925 }
926
927 printk(KERN_WARNING "%s: no symbol version for %s\n",
928 mod->name, symname);
929 return 0;
930
931bad_version:
932 printk("%s: disagrees about version of symbol %s\n",
933 mod->name, symname);
934 return 0;
935}
936
937static inline int check_modstruct_version(Elf_Shdr *sechdrs,
938 unsigned int versindex,
939 struct module *mod)
940{
941 const unsigned long *crc;
942
943 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
944 &crc, true, false))
945 BUG();
946 return check_version(sechdrs, versindex, "module_layout", mod, crc,
947 NULL);
948}
949
950/* First part is kernel version, which we ignore if module has crcs. */
951static inline int same_magic(const char *amagic, const char *bmagic,
952 bool has_crcs)
953{
954 if (has_crcs) {
955 amagic += strcspn(amagic, " ");
956 bmagic += strcspn(bmagic, " ");
957 }
958 return strcmp(amagic, bmagic) == 0;
959}
960#else
961static inline int check_version(Elf_Shdr *sechdrs,
962 unsigned int versindex,
963 const char *symname,
964 struct module *mod,
965 const unsigned long *crc,
966 const struct module *crc_owner)
967{
968 return 1;
969}
970
971static inline int check_modstruct_version(Elf_Shdr *sechdrs,
972 unsigned int versindex,
973 struct module *mod)
974{
975 return 1;
976}
977
978static inline int same_magic(const char *amagic, const char *bmagic,
979 bool has_crcs)
980{
981 return strcmp(amagic, bmagic) == 0;
982}
983#endif /* CONFIG_MODVERSIONS */
984
985/* Resolve a symbol for this module. I.e. if we find one, record usage.
986 Must be holding module_mutex. */
987static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
988 unsigned int versindex,
989 const char *name,
990 struct module *mod)
991{
992 struct module *owner;
993 const struct kernel_symbol *sym;
994 const unsigned long *crc;
995
996 sym = find_symbol(name, &owner, &crc,
997 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
998 /* use_module can fail due to OOM,
999 or module initialization or unloading */
1000 if (sym) {
1001 if (!check_version(sechdrs, versindex, name, mod, crc, owner)
1002 || !use_module(mod, owner))
1003 sym = NULL;
1004 }
1005 return sym;
1006}
1007
1008/*
1009 * /sys/module/foo/sections stuff
1010 * J. Corbet <[email protected]>
1011 */
1012#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1013struct module_sect_attr
1014{
1015 struct module_attribute mattr;
1016 char *name;
1017 unsigned long address;
1018};
1019
1020struct module_sect_attrs
1021{
1022 struct attribute_group grp;
1023 unsigned int nsections;
1024 struct module_sect_attr attrs[0];
1025};
1026
1027static ssize_t module_sect_show(struct module_attribute *mattr,
1028 struct module *mod, char *buf)
1029{
1030 struct module_sect_attr *sattr =
1031 container_of(mattr, struct module_sect_attr, mattr);
1032 return sprintf(buf, "0x%lx\n", sattr->address);
1033}
1034
1035static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1036{
1037 unsigned int section;
1038
1039 for (section = 0; section < sect_attrs->nsections; section++)
1040 kfree(sect_attrs->attrs[section].name);
1041 kfree(sect_attrs);
1042}
1043
1044static void add_sect_attrs(struct module *mod, unsigned int nsect,
1045 char *secstrings, Elf_Shdr *sechdrs)
1046{
1047 unsigned int nloaded = 0, i, size[2];
1048 struct module_sect_attrs *sect_attrs;
1049 struct module_sect_attr *sattr;
1050 struct attribute **gattr;
1051
1052 /* Count loaded sections and allocate structures */
1053 for (i = 0; i < nsect; i++)
1054 if (sechdrs[i].sh_flags & SHF_ALLOC
1055 && sechdrs[i].sh_size)
1056 nloaded++;
1057 size[0] = ALIGN(sizeof(*sect_attrs)
1058 + nloaded * sizeof(sect_attrs->attrs[0]),
1059 sizeof(sect_attrs->grp.attrs[0]));
1060 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1061 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1062 if (sect_attrs == NULL)
1063 return;
1064
1065 /* Setup section attributes. */
1066 sect_attrs->grp.name = "sections";
1067 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1068
1069 sect_attrs->nsections = 0;
1070 sattr = &sect_attrs->attrs[0];
1071 gattr = &sect_attrs->grp.attrs[0];
1072 for (i = 0; i < nsect; i++) {
1073 if (! (sechdrs[i].sh_flags & SHF_ALLOC))
1074 continue;
1075 if (!sechdrs[i].sh_size)
1076 continue;
1077 sattr->address = sechdrs[i].sh_addr;
1078 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1079 GFP_KERNEL);
1080 if (sattr->name == NULL)
1081 goto out;
1082 sect_attrs->nsections++;
1083 sattr->mattr.show = module_sect_show;
1084 sattr->mattr.store = NULL;
1085 sattr->mattr.attr.name = sattr->name;
1086 sattr->mattr.attr.mode = S_IRUGO;
1087 *(gattr++) = &(sattr++)->mattr.attr;
1088 }
1089 *gattr = NULL;
1090
1091 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1092 goto out;
1093
1094 mod->sect_attrs = sect_attrs;
1095 return;
1096 out:
1097 free_sect_attrs(sect_attrs);
1098}
1099
1100static void remove_sect_attrs(struct module *mod)
1101{
1102 if (mod->sect_attrs) {
1103 sysfs_remove_group(&mod->mkobj.kobj,
1104 &mod->sect_attrs->grp);
1105 /* We are positive that no one is using any sect attrs
1106 * at this point. Deallocate immediately. */
1107 free_sect_attrs(mod->sect_attrs);
1108 mod->sect_attrs = NULL;
1109 }
1110}
1111
1112/*
1113 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1114 */
1115
1116struct module_notes_attrs {
1117 struct kobject *dir;
1118 unsigned int notes;
1119 struct bin_attribute attrs[0];
1120};
1121
1122static ssize_t module_notes_read(struct kobject *kobj,
1123 struct bin_attribute *bin_attr,
1124 char *buf, loff_t pos, size_t count)
1125{
1126 /*
1127 * The caller checked the pos and count against our size.
1128 */
1129 memcpy(buf, bin_attr->private + pos, count);
1130 return count;
1131}
1132
1133static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1134 unsigned int i)
1135{
1136 if (notes_attrs->dir) {
1137 while (i-- > 0)
1138 sysfs_remove_bin_file(notes_attrs->dir,
1139 &notes_attrs->attrs[i]);
1140 kobject_put(notes_attrs->dir);
1141 }
1142 kfree(notes_attrs);
1143}
1144
1145static void add_notes_attrs(struct module *mod, unsigned int nsect,
1146 char *secstrings, Elf_Shdr *sechdrs)
1147{
1148 unsigned int notes, loaded, i;
1149 struct module_notes_attrs *notes_attrs;
1150 struct bin_attribute *nattr;
1151
1152 /* failed to create section attributes, so can't create notes */
1153 if (!mod->sect_attrs)
1154 return;
1155
1156 /* Count notes sections and allocate structures. */
1157 notes = 0;
1158 for (i = 0; i < nsect; i++)
1159 if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
1160 (sechdrs[i].sh_type == SHT_NOTE))
1161 ++notes;
1162
1163 if (notes == 0)
1164 return;
1165
1166 notes_attrs = kzalloc(sizeof(*notes_attrs)
1167 + notes * sizeof(notes_attrs->attrs[0]),
1168 GFP_KERNEL);
1169 if (notes_attrs == NULL)
1170 return;
1171
1172 notes_attrs->notes = notes;
1173 nattr = &notes_attrs->attrs[0];
1174 for (loaded = i = 0; i < nsect; ++i) {
1175 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1176 continue;
1177 if (sechdrs[i].sh_type == SHT_NOTE) {
1178 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1179 nattr->attr.mode = S_IRUGO;
1180 nattr->size = sechdrs[i].sh_size;
1181 nattr->private = (void *) sechdrs[i].sh_addr;
1182 nattr->read = module_notes_read;
1183 ++nattr;
1184 }
1185 ++loaded;
1186 }
1187
1188 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1189 if (!notes_attrs->dir)
1190 goto out;
1191
1192 for (i = 0; i < notes; ++i)
1193 if (sysfs_create_bin_file(notes_attrs->dir,
1194 &notes_attrs->attrs[i]))
1195 goto out;
1196
1197 mod->notes_attrs = notes_attrs;
1198 return;
1199
1200 out:
1201 free_notes_attrs(notes_attrs, i);
1202}
1203
1204static void remove_notes_attrs(struct module *mod)
1205{
1206 if (mod->notes_attrs)
1207 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1208}
1209
1210#else
1211
1212static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1213 char *sectstrings, Elf_Shdr *sechdrs)
1214{
1215}
1216
1217static inline void remove_sect_attrs(struct module *mod)
1218{
1219}
1220
1221static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1222 char *sectstrings, Elf_Shdr *sechdrs)
1223{
1224}
1225
1226static inline void remove_notes_attrs(struct module *mod)
1227{
1228}
1229#endif
1230
1231#ifdef CONFIG_SYSFS
1232int module_add_modinfo_attrs(struct module *mod)
1233{
1234 struct module_attribute *attr;
1235 struct module_attribute *temp_attr;
1236 int error = 0;
1237 int i;
1238
1239 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1240 (ARRAY_SIZE(modinfo_attrs) + 1)),
1241 GFP_KERNEL);
1242 if (!mod->modinfo_attrs)
1243 return -ENOMEM;
1244
1245 temp_attr = mod->modinfo_attrs;
1246 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1247 if (!attr->test ||
1248 (attr->test && attr->test(mod))) {
1249 memcpy(temp_attr, attr, sizeof(*temp_attr));
1250 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1251 ++temp_attr;
1252 }
1253 }
1254 return error;
1255}
1256
1257void module_remove_modinfo_attrs(struct module *mod)
1258{
1259 struct module_attribute *attr;
1260 int i;
1261
1262 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1263 /* pick a field to test for end of list */
1264 if (!attr->attr.name)
1265 break;
1266 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1267 if (attr->free)
1268 attr->free(mod);
1269 }
1270 kfree(mod->modinfo_attrs);
1271}
1272
1273int mod_sysfs_init(struct module *mod)
1274{
1275 int err;
1276 struct kobject *kobj;
1277
1278 if (!module_sysfs_initialized) {
1279 printk(KERN_ERR "%s: module sysfs not initialized\n",
1280 mod->name);
1281 err = -EINVAL;
1282 goto out;
1283 }
1284
1285 kobj = kset_find_obj(module_kset, mod->name);
1286 if (kobj) {
1287 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1288 kobject_put(kobj);
1289 err = -EINVAL;
1290 goto out;
1291 }
1292
1293 mod->mkobj.mod = mod;
1294
1295 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1296 mod->mkobj.kobj.kset = module_kset;
1297 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1298 "%s", mod->name);
1299 if (err)
1300 kobject_put(&mod->mkobj.kobj);
1301
1302 /* delay uevent until full sysfs population */
1303out:
1304 return err;
1305}
1306
1307int mod_sysfs_setup(struct module *mod,
1308 struct kernel_param *kparam,
1309 unsigned int num_params)
1310{
1311 int err;
1312
1313 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1314 if (!mod->holders_dir) {
1315 err = -ENOMEM;
1316 goto out_unreg;
1317 }
1318
1319 err = module_param_sysfs_setup(mod, kparam, num_params);
1320 if (err)
1321 goto out_unreg_holders;
1322
1323 err = module_add_modinfo_attrs(mod);
1324 if (err)
1325 goto out_unreg_param;
1326
1327 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1328 return 0;
1329
1330out_unreg_param:
1331 module_param_sysfs_remove(mod);
1332out_unreg_holders:
1333 kobject_put(mod->holders_dir);
1334out_unreg:
1335 kobject_put(&mod->mkobj.kobj);
1336 return err;
1337}
1338
1339static void mod_sysfs_fini(struct module *mod)
1340{
1341 kobject_put(&mod->mkobj.kobj);
1342}
1343
1344#else /* CONFIG_SYSFS */
1345
1346static void mod_sysfs_fini(struct module *mod)
1347{
1348}
1349
1350#endif /* CONFIG_SYSFS */
1351
1352static void mod_kobject_remove(struct module *mod)
1353{
1354 module_remove_modinfo_attrs(mod);
1355 module_param_sysfs_remove(mod);
1356 kobject_put(mod->mkobj.drivers_dir);
1357 kobject_put(mod->holders_dir);
1358 mod_sysfs_fini(mod);
1359}
1360
1361/*
1362 * unlink the module with the whole machine is stopped with interrupts off
1363 * - this defends against kallsyms not taking locks
1364 */
1365static int __unlink_module(void *_mod)
1366{
1367 struct module *mod = _mod;
1368 list_del(&mod->list);
1369 return 0;
1370}
1371
1372/* Free a module, remove from lists, etc (must hold module_mutex). */
1373static void free_module(struct module *mod)
1374{
1375 trace_module_free(mod);
1376
1377 /* Delete from various lists */
1378 stop_machine(__unlink_module, mod, NULL);
1379 remove_notes_attrs(mod);
1380 remove_sect_attrs(mod);
1381 mod_kobject_remove(mod);
1382
1383 /* Arch-specific cleanup. */
1384 module_arch_cleanup(mod);
1385
1386 /* Module unload stuff */
1387 module_unload_free(mod);
1388
1389 /* Free any allocated parameters. */
1390 destroy_params(mod->kp, mod->num_kp);
1391
1392 /* This may be NULL, but that's OK */
1393 module_free(mod, mod->module_init);
1394 kfree(mod->args);
1395 if (mod->percpu)
1396 percpu_modfree(mod->percpu);
1397#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
1398 if (mod->refptr)
1399 percpu_modfree(mod->refptr);
1400#endif
1401 /* Free lock-classes: */
1402 lockdep_free_key_range(mod->module_core, mod->core_size);
1403
1404 /* Finally, free the core (containing the module structure) */
1405 module_free(mod, mod->module_core);
1406
1407#ifdef CONFIG_MPU
1408 update_protections(current->mm);
1409#endif
1410}
1411
1412void *__symbol_get(const char *symbol)
1413{
1414 struct module *owner;
1415 const struct kernel_symbol *sym;
1416
1417 preempt_disable();
1418 sym = find_symbol(symbol, &owner, NULL, true, true);
1419 if (sym && strong_try_module_get(owner))
1420 sym = NULL;
1421 preempt_enable();
1422
1423 return sym ? (void *)sym->value : NULL;
1424}
1425EXPORT_SYMBOL_GPL(__symbol_get);
1426
1427/*
1428 * Ensure that an exported symbol [global namespace] does not already exist
1429 * in the kernel or in some other module's exported symbol table.
1430 */
1431static int verify_export_symbols(struct module *mod)
1432{
1433 unsigned int i;
1434 struct module *owner;
1435 const struct kernel_symbol *s;
1436 struct {
1437 const struct kernel_symbol *sym;
1438 unsigned int num;
1439 } arr[] = {
1440 { mod->syms, mod->num_syms },
1441 { mod->gpl_syms, mod->num_gpl_syms },
1442 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1443#ifdef CONFIG_UNUSED_SYMBOLS
1444 { mod->unused_syms, mod->num_unused_syms },
1445 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1446#endif
1447 };
1448
1449 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1450 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1451 if (find_symbol(s->name, &owner, NULL, true, false)) {
1452 printk(KERN_ERR
1453 "%s: exports duplicate symbol %s"
1454 " (owned by %s)\n",
1455 mod->name, s->name, module_name(owner));
1456 return -ENOEXEC;
1457 }
1458 }
1459 }
1460 return 0;
1461}
1462
1463/* Change all symbols so that st_value encodes the pointer directly. */
1464static int simplify_symbols(Elf_Shdr *sechdrs,
1465 unsigned int symindex,
1466 const char *strtab,
1467 unsigned int versindex,
1468 unsigned int pcpuindex,
1469 struct module *mod)
1470{
1471 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1472 unsigned long secbase;
1473 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1474 int ret = 0;
1475 const struct kernel_symbol *ksym;
1476
1477 for (i = 1; i < n; i++) {
1478 switch (sym[i].st_shndx) {
1479 case SHN_COMMON:
1480 /* We compiled with -fno-common. These are not
1481 supposed to happen. */
1482 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1483 printk("%s: please compile with -fno-common\n",
1484 mod->name);
1485 ret = -ENOEXEC;
1486 break;
1487
1488 case SHN_ABS:
1489 /* Don't need to do anything */
1490 DEBUGP("Absolute symbol: 0x%08lx\n",
1491 (long)sym[i].st_value);
1492 break;
1493
1494 case SHN_UNDEF:
1495 ksym = resolve_symbol(sechdrs, versindex,
1496 strtab + sym[i].st_name, mod);
1497 /* Ok if resolved. */
1498 if (ksym) {
1499 sym[i].st_value = ksym->value;
1500 break;
1501 }
1502
1503 /* Ok if weak. */
1504 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1505 break;
1506
1507 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1508 mod->name, strtab + sym[i].st_name);
1509 ret = -ENOENT;
1510 break;
1511
1512 default:
1513 /* Divert to percpu allocation if a percpu var. */
1514 if (sym[i].st_shndx == pcpuindex)
1515 secbase = (unsigned long)mod->percpu;
1516 else
1517 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1518 sym[i].st_value += secbase;
1519 break;
1520 }
1521 }
1522
1523 return ret;
1524}
1525
1526/* Additional bytes needed by arch in front of individual sections */
1527unsigned int __weak arch_mod_section_prepend(struct module *mod,
1528 unsigned int section)
1529{
1530 /* default implementation just returns zero */
1531 return 0;
1532}
1533
1534/* Update size with this section: return offset. */
1535static long get_offset(struct module *mod, unsigned int *size,
1536 Elf_Shdr *sechdr, unsigned int section)
1537{
1538 long ret;
1539
1540 *size += arch_mod_section_prepend(mod, section);
1541 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1542 *size = ret + sechdr->sh_size;
1543 return ret;
1544}
1545
1546/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1547 might -- code, read-only data, read-write data, small data. Tally
1548 sizes, and place the offsets into sh_entsize fields: high bit means it
1549 belongs in init. */
1550static void layout_sections(struct module *mod,
1551 const Elf_Ehdr *hdr,
1552 Elf_Shdr *sechdrs,
1553 const char *secstrings)
1554{
1555 static unsigned long const masks[][2] = {
1556 /* NOTE: all executable code must be the first section
1557 * in this array; otherwise modify the text_size
1558 * finder in the two loops below */
1559 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1560 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1561 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1562 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1563 };
1564 unsigned int m, i;
1565
1566 for (i = 0; i < hdr->e_shnum; i++)
1567 sechdrs[i].sh_entsize = ~0UL;
1568
1569 DEBUGP("Core section allocation order:\n");
1570 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1571 for (i = 0; i < hdr->e_shnum; ++i) {
1572 Elf_Shdr *s = &sechdrs[i];
1573
1574 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1575 || (s->sh_flags & masks[m][1])
1576 || s->sh_entsize != ~0UL
1577 || strstarts(secstrings + s->sh_name, ".init"))
1578 continue;
1579 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1580 DEBUGP("\t%s\n", secstrings + s->sh_name);
1581 }
1582 if (m == 0)
1583 mod->core_text_size = mod->core_size;
1584 }
1585
1586 DEBUGP("Init section allocation order:\n");
1587 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1588 for (i = 0; i < hdr->e_shnum; ++i) {
1589 Elf_Shdr *s = &sechdrs[i];
1590
1591 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1592 || (s->sh_flags & masks[m][1])
1593 || s->sh_entsize != ~0UL
1594 || !strstarts(secstrings + s->sh_name, ".init"))
1595 continue;
1596 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1597 | INIT_OFFSET_MASK);
1598 DEBUGP("\t%s\n", secstrings + s->sh_name);
1599 }
1600 if (m == 0)
1601 mod->init_text_size = mod->init_size;
1602 }
1603}
1604
1605static void set_license(struct module *mod, const char *license)
1606{
1607 if (!license)
1608 license = "unspecified";
1609
1610 if (!license_is_gpl_compatible(license)) {
1611 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1612 printk(KERN_WARNING "%s: module license '%s' taints "
1613 "kernel.\n", mod->name, license);
1614 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1615 }
1616}
1617
1618/* Parse tag=value strings from .modinfo section */
1619static char *next_string(char *string, unsigned long *secsize)
1620{
1621 /* Skip non-zero chars */
1622 while (string[0]) {
1623 string++;
1624 if ((*secsize)-- <= 1)
1625 return NULL;
1626 }
1627
1628 /* Skip any zero padding. */
1629 while (!string[0]) {
1630 string++;
1631 if ((*secsize)-- <= 1)
1632 return NULL;
1633 }
1634 return string;
1635}
1636
1637static char *get_modinfo(Elf_Shdr *sechdrs,
1638 unsigned int info,
1639 const char *tag)
1640{
1641 char *p;
1642 unsigned int taglen = strlen(tag);
1643 unsigned long size = sechdrs[info].sh_size;
1644
1645 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1646 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1647 return p + taglen + 1;
1648 }
1649 return NULL;
1650}
1651
1652static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1653 unsigned int infoindex)
1654{
1655 struct module_attribute *attr;
1656 int i;
1657
1658 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1659 if (attr->setup)
1660 attr->setup(mod,
1661 get_modinfo(sechdrs,
1662 infoindex,
1663 attr->attr.name));
1664 }
1665}
1666
1667static void free_modinfo(struct module *mod)
1668{
1669 struct module_attribute *attr;
1670 int i;
1671
1672 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1673 if (attr->free)
1674 attr->free(mod);
1675 }
1676}
1677
1678#ifdef CONFIG_KALLSYMS
1679
1680/* lookup symbol in given range of kernel_symbols */
1681static const struct kernel_symbol *lookup_symbol(const char *name,
1682 const struct kernel_symbol *start,
1683 const struct kernel_symbol *stop)
1684{
1685 const struct kernel_symbol *ks = start;
1686 for (; ks < stop; ks++)
1687 if (strcmp(ks->name, name) == 0)
1688 return ks;
1689 return NULL;
1690}
1691
1692static int is_exported(const char *name, unsigned long value,
1693 const struct module *mod)
1694{
1695 const struct kernel_symbol *ks;
1696 if (!mod)
1697 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1698 else
1699 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1700 return ks != NULL && ks->value == value;
1701}
1702
1703/* As per nm */
1704static char elf_type(const Elf_Sym *sym,
1705 Elf_Shdr *sechdrs,
1706 const char *secstrings,
1707 struct module *mod)
1708{
1709 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1710 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1711 return 'v';
1712 else
1713 return 'w';
1714 }
1715 if (sym->st_shndx == SHN_UNDEF)
1716 return 'U';
1717 if (sym->st_shndx == SHN_ABS)
1718 return 'a';
1719 if (sym->st_shndx >= SHN_LORESERVE)
1720 return '?';
1721 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1722 return 't';
1723 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1724 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1725 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1726 return 'r';
1727 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1728 return 'g';
1729 else
1730 return 'd';
1731 }
1732 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1733 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1734 return 's';
1735 else
1736 return 'b';
1737 }
1738 if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug"))
1739 return 'n';
1740 return '?';
1741}
1742
1743static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1744 unsigned int shnum)
1745{
1746 const Elf_Shdr *sec;
1747
1748 if (src->st_shndx == SHN_UNDEF
1749 || src->st_shndx >= shnum
1750 || !src->st_name)
1751 return false;
1752
1753 sec = sechdrs + src->st_shndx;
1754 if (!(sec->sh_flags & SHF_ALLOC)
1755#ifndef CONFIG_KALLSYMS_ALL
1756 || !(sec->sh_flags & SHF_EXECINSTR)
1757#endif
1758 || (sec->sh_entsize & INIT_OFFSET_MASK))
1759 return false;
1760
1761 return true;
1762}
1763
1764static unsigned long layout_symtab(struct module *mod,
1765 Elf_Shdr *sechdrs,
1766 unsigned int symindex,
1767 unsigned int strindex,
1768 const Elf_Ehdr *hdr,
1769 const char *secstrings,
1770 unsigned long *pstroffs,
1771 unsigned long *strmap)
1772{
1773 unsigned long symoffs;
1774 Elf_Shdr *symsect = sechdrs + symindex;
1775 Elf_Shdr *strsect = sechdrs + strindex;
1776 const Elf_Sym *src;
1777 const char *strtab;
1778 unsigned int i, nsrc, ndst;
1779
1780 /* Put symbol section at end of init part of module. */
1781 symsect->sh_flags |= SHF_ALLOC;
1782 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1783 symindex) | INIT_OFFSET_MASK;
1784 DEBUGP("\t%s\n", secstrings + symsect->sh_name);
1785
1786 src = (void *)hdr + symsect->sh_offset;
1787 nsrc = symsect->sh_size / sizeof(*src);
1788 strtab = (void *)hdr + strsect->sh_offset;
1789 for (ndst = i = 1; i < nsrc; ++i, ++src)
1790 if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
1791 unsigned int j = src->st_name;
1792
1793 while(!__test_and_set_bit(j, strmap) && strtab[j])
1794 ++j;
1795 ++ndst;
1796 }
1797
1798 /* Append room for core symbols at end of core part. */
1799 symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
1800 mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
1801
1802 /* Put string table section at end of init part of module. */
1803 strsect->sh_flags |= SHF_ALLOC;
1804 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
1805 strindex) | INIT_OFFSET_MASK;
1806 DEBUGP("\t%s\n", secstrings + strsect->sh_name);
1807
1808 /* Append room for core symbols' strings at end of core part. */
1809 *pstroffs = mod->core_size;
1810 __set_bit(0, strmap);
1811 mod->core_size += bitmap_weight(strmap, strsect->sh_size);
1812
1813 return symoffs;
1814}
1815
1816static void add_kallsyms(struct module *mod,
1817 Elf_Shdr *sechdrs,
1818 unsigned int shnum,
1819 unsigned int symindex,
1820 unsigned int strindex,
1821 unsigned long symoffs,
1822 unsigned long stroffs,
1823 const char *secstrings,
1824 unsigned long *strmap)
1825{
1826 unsigned int i, ndst;
1827 const Elf_Sym *src;
1828 Elf_Sym *dst;
1829 char *s;
1830
1831 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1832 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1833 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1834
1835 /* Set types up while we still have access to sections. */
1836 for (i = 0; i < mod->num_symtab; i++)
1837 mod->symtab[i].st_info
1838 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1839
1840 mod->core_symtab = dst = mod->module_core + symoffs;
1841 src = mod->symtab;
1842 *dst = *src;
1843 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
1844 if (!is_core_symbol(src, sechdrs, shnum))
1845 continue;
1846 dst[ndst] = *src;
1847 dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
1848 ++ndst;
1849 }
1850 mod->core_num_syms = ndst;
1851
1852 mod->core_strtab = s = mod->module_core + stroffs;
1853 for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i)
1854 if (test_bit(i, strmap))
1855 *++s = mod->strtab[i];
1856}
1857#else
1858static inline unsigned long layout_symtab(struct module *mod,
1859 Elf_Shdr *sechdrs,
1860 unsigned int symindex,
1861 unsigned int strindex,
1862 const Elf_Ehdr *hdr,
1863 const char *secstrings,
1864 unsigned long *pstroffs,
1865 unsigned long *strmap)
1866{
1867 return 0;
1868}
1869
1870static inline void add_kallsyms(struct module *mod,
1871 Elf_Shdr *sechdrs,
1872 unsigned int shnum,
1873 unsigned int symindex,
1874 unsigned int strindex,
1875 unsigned long symoffs,
1876 unsigned long stroffs,
1877 const char *secstrings,
1878 const unsigned long *strmap)
1879{
1880}
1881#endif /* CONFIG_KALLSYMS */
1882
1883static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
1884{
1885#ifdef CONFIG_DYNAMIC_DEBUG
1886 if (ddebug_add_module(debug, num, debug->modname))
1887 printk(KERN_ERR "dynamic debug error adding module: %s\n",
1888 debug->modname);
1889#endif
1890}
1891
1892static void *module_alloc_update_bounds(unsigned long size)
1893{
1894 void *ret = module_alloc(size);
1895
1896 if (ret) {
1897 /* Update module bounds. */
1898 if ((unsigned long)ret < module_addr_min)
1899 module_addr_min = (unsigned long)ret;
1900 if ((unsigned long)ret + size > module_addr_max)
1901 module_addr_max = (unsigned long)ret + size;
1902 }
1903 return ret;
1904}
1905
1906#ifdef CONFIG_DEBUG_KMEMLEAK
1907static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
1908 Elf_Shdr *sechdrs, char *secstrings)
1909{
1910 unsigned int i;
1911
1912 /* only scan the sections containing data */
1913 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
1914
1915 for (i = 1; i < hdr->e_shnum; i++) {
1916 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1917 continue;
1918 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
1919 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
1920 continue;
1921
1922 kmemleak_scan_area((void *)sechdrs[i].sh_addr,
1923 sechdrs[i].sh_size, GFP_KERNEL);
1924 }
1925}
1926#else
1927static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
1928 Elf_Shdr *sechdrs, char *secstrings)
1929{
1930}
1931#endif
1932
1933/* Allocate and load the module: note that size of section 0 is always
1934 zero, and we rely on this for optional sections. */
1935static noinline struct module *load_module(void __user *umod,
1936 unsigned long len,
1937 const char __user *uargs)
1938{
1939 Elf_Ehdr *hdr;
1940 Elf_Shdr *sechdrs;
1941 char *secstrings, *args, *modmagic, *strtab = NULL;
1942 char *staging;
1943 unsigned int i;
1944 unsigned int symindex = 0;
1945 unsigned int strindex = 0;
1946 unsigned int modindex, versindex, infoindex, pcpuindex;
1947 struct module *mod;
1948 long err = 0;
1949 void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
1950 unsigned long symoffs, stroffs, *strmap;
1951
1952 mm_segment_t old_fs;
1953
1954 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
1955 umod, len, uargs);
1956 if (len < sizeof(*hdr))
1957 return ERR_PTR(-ENOEXEC);
1958
1959 /* Suck in entire file: we'll want most of it. */
1960 /* vmalloc barfs on "unusual" numbers. Check here */
1961 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
1962 return ERR_PTR(-ENOMEM);
1963
1964 if (copy_from_user(hdr, umod, len) != 0) {
1965 err = -EFAULT;
1966 goto free_hdr;
1967 }
1968
1969 /* Sanity checks against insmoding binaries or wrong arch,
1970 weird elf version */
1971 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
1972 || hdr->e_type != ET_REL
1973 || !elf_check_arch(hdr)
1974 || hdr->e_shentsize != sizeof(*sechdrs)) {
1975 err = -ENOEXEC;
1976 goto free_hdr;
1977 }
1978
1979 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
1980 goto truncated;
1981
1982 /* Convenience variables */
1983 sechdrs = (void *)hdr + hdr->e_shoff;
1984 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
1985 sechdrs[0].sh_addr = 0;
1986
1987 for (i = 1; i < hdr->e_shnum; i++) {
1988 if (sechdrs[i].sh_type != SHT_NOBITS
1989 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
1990 goto truncated;
1991
1992 /* Mark all sections sh_addr with their address in the
1993 temporary image. */
1994 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
1995
1996 /* Internal symbols and strings. */
1997 if (sechdrs[i].sh_type == SHT_SYMTAB) {
1998 symindex = i;
1999 strindex = sechdrs[i].sh_link;
2000 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
2001 }
2002#ifndef CONFIG_MODULE_UNLOAD
2003 /* Don't load .exit sections */
2004 if (strstarts(secstrings+sechdrs[i].sh_name, ".exit"))
2005 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
2006#endif
2007 }
2008
2009 modindex = find_sec(hdr, sechdrs, secstrings,
2010 ".gnu.linkonce.this_module");
2011 if (!modindex) {
2012 printk(KERN_WARNING "No module found in object\n");
2013 err = -ENOEXEC;
2014 goto free_hdr;
2015 }
2016 /* This is temporary: point mod into copy of data. */
2017 mod = (void *)sechdrs[modindex].sh_addr;
2018
2019 if (symindex == 0) {
2020 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2021 mod->name);
2022 err = -ENOEXEC;
2023 goto free_hdr;
2024 }
2025
2026 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
2027 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
2028 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
2029
2030 /* Don't keep modinfo and version sections. */
2031 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2032 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2033
2034 /* Check module struct version now, before we try to use module. */
2035 if (!check_modstruct_version(sechdrs, versindex, mod)) {
2036 err = -ENOEXEC;
2037 goto free_hdr;
2038 }
2039
2040 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2041 /* This is allowed: modprobe --force will invalidate it. */
2042 if (!modmagic) {
2043 err = try_to_force_load(mod, "bad vermagic");
2044 if (err)
2045 goto free_hdr;
2046 } else if (!same_magic(modmagic, vermagic, versindex)) {
2047 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2048 mod->name, modmagic, vermagic);
2049 err = -ENOEXEC;
2050 goto free_hdr;
2051 }
2052
2053 staging = get_modinfo(sechdrs, infoindex, "staging");
2054 if (staging) {
2055 add_taint_module(mod, TAINT_CRAP);
2056 printk(KERN_WARNING "%s: module is from the staging directory,"
2057 " the quality is unknown, you have been warned.\n",
2058 mod->name);
2059 }
2060
2061 /* Now copy in args */
2062 args = strndup_user(uargs, ~0UL >> 1);
2063 if (IS_ERR(args)) {
2064 err = PTR_ERR(args);
2065 goto free_hdr;
2066 }
2067
2068 strmap = kzalloc(BITS_TO_LONGS(sechdrs[strindex].sh_size)
2069 * sizeof(long), GFP_KERNEL);
2070 if (!strmap) {
2071 err = -ENOMEM;
2072 goto free_mod;
2073 }
2074
2075 if (find_module(mod->name)) {
2076 err = -EEXIST;
2077 goto free_mod;
2078 }
2079
2080 mod->state = MODULE_STATE_COMING;
2081
2082 /* Allow arches to frob section contents and sizes. */
2083 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
2084 if (err < 0)
2085 goto free_mod;
2086
2087 if (pcpuindex) {
2088 /* We have a special allocation for this section. */
2089 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
2090 sechdrs[pcpuindex].sh_addralign,
2091 mod->name);
2092 if (!percpu) {
2093 err = -ENOMEM;
2094 goto free_mod;
2095 }
2096 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2097 mod->percpu = percpu;
2098 }
2099
2100 /* Determine total sizes, and put offsets in sh_entsize. For now
2101 this is done generically; there doesn't appear to be any
2102 special cases for the architectures. */
2103 layout_sections(mod, hdr, sechdrs, secstrings);
2104 symoffs = layout_symtab(mod, sechdrs, symindex, strindex, hdr,
2105 secstrings, &stroffs, strmap);
2106
2107 /* Do the allocs. */
2108 ptr = module_alloc_update_bounds(mod->core_size);
2109 /*
2110 * The pointer to this block is stored in the module structure
2111 * which is inside the block. Just mark it as not being a
2112 * leak.
2113 */
2114 kmemleak_not_leak(ptr);
2115 if (!ptr) {
2116 err = -ENOMEM;
2117 goto free_percpu;
2118 }
2119 memset(ptr, 0, mod->core_size);
2120 mod->module_core = ptr;
2121
2122 ptr = module_alloc_update_bounds(mod->init_size);
2123 /*
2124 * The pointer to this block is stored in the module structure
2125 * which is inside the block. This block doesn't need to be
2126 * scanned as it contains data and code that will be freed
2127 * after the module is initialized.
2128 */
2129 kmemleak_ignore(ptr);
2130 if (!ptr && mod->init_size) {
2131 err = -ENOMEM;
2132 goto free_core;
2133 }
2134 memset(ptr, 0, mod->init_size);
2135 mod->module_init = ptr;
2136
2137 /* Transfer each section which specifies SHF_ALLOC */
2138 DEBUGP("final section addresses:\n");
2139 for (i = 0; i < hdr->e_shnum; i++) {
2140 void *dest;
2141
2142 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2143 continue;
2144
2145 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2146 dest = mod->module_init
2147 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2148 else
2149 dest = mod->module_core + sechdrs[i].sh_entsize;
2150
2151 if (sechdrs[i].sh_type != SHT_NOBITS)
2152 memcpy(dest, (void *)sechdrs[i].sh_addr,
2153 sechdrs[i].sh_size);
2154 /* Update sh_addr to point to copy in image. */
2155 sechdrs[i].sh_addr = (unsigned long)dest;
2156 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2157 }
2158 /* Module has been moved. */
2159 mod = (void *)sechdrs[modindex].sh_addr;
2160 kmemleak_load_module(mod, hdr, sechdrs, secstrings);
2161
2162#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
2163 mod->refptr = percpu_modalloc(sizeof(local_t), __alignof__(local_t),
2164 mod->name);
2165 if (!mod->refptr) {
2166 err = -ENOMEM;
2167 goto free_init;
2168 }
2169#endif
2170 /* Now we've moved module, initialize linked lists, etc. */
2171 module_unload_init(mod);
2172
2173 /* add kobject, so we can reference it. */
2174 err = mod_sysfs_init(mod);
2175 if (err)
2176 goto free_unload;
2177
2178 /* Set up license info based on the info section */
2179 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2180
2181 /*
2182 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2183 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2184 * using GPL-only symbols it needs.
2185 */
2186 if (strcmp(mod->name, "ndiswrapper") == 0)
2187 add_taint(TAINT_PROPRIETARY_MODULE);
2188
2189 /* driverloader was caught wrongly pretending to be under GPL */
2190 if (strcmp(mod->name, "driverloader") == 0)
2191 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2192
2193 /* Set up MODINFO_ATTR fields */
2194 setup_modinfo(mod, sechdrs, infoindex);
2195
2196 /* Fix up syms, so that st_value is a pointer to location. */
2197 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2198 mod);
2199 if (err < 0)
2200 goto cleanup;
2201
2202 /* Now we've got everything in the final locations, we can
2203 * find optional sections. */
2204 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2205 sizeof(*mod->kp), &mod->num_kp);
2206 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2207 sizeof(*mod->syms), &mod->num_syms);
2208 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2209 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2210 sizeof(*mod->gpl_syms),
2211 &mod->num_gpl_syms);
2212 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2213 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2214 "__ksymtab_gpl_future",
2215 sizeof(*mod->gpl_future_syms),
2216 &mod->num_gpl_future_syms);
2217 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2218 "__kcrctab_gpl_future");
2219
2220#ifdef CONFIG_UNUSED_SYMBOLS
2221 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2222 "__ksymtab_unused",
2223 sizeof(*mod->unused_syms),
2224 &mod->num_unused_syms);
2225 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2226 "__kcrctab_unused");
2227 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2228 "__ksymtab_unused_gpl",
2229 sizeof(*mod->unused_gpl_syms),
2230 &mod->num_unused_gpl_syms);
2231 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2232 "__kcrctab_unused_gpl");
2233#endif
2234#ifdef CONFIG_CONSTRUCTORS
2235 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2236 sizeof(*mod->ctors), &mod->num_ctors);
2237#endif
2238
2239#ifdef CONFIG_TRACEPOINTS
2240 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2241 "__tracepoints",
2242 sizeof(*mod->tracepoints),
2243 &mod->num_tracepoints);
2244#endif
2245#ifdef CONFIG_EVENT_TRACING
2246 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2247 "_ftrace_events",
2248 sizeof(*mod->trace_events),
2249 &mod->num_trace_events);
2250 /*
2251 * This section contains pointers to allocated objects in the trace
2252 * code and not scanning it leads to false positives.
2253 */
2254 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2255 mod->num_trace_events, GFP_KERNEL);
2256#endif
2257#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2258 /* sechdrs[0].sh_size is always zero */
2259 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2260 "__mcount_loc",
2261 sizeof(*mod->ftrace_callsites),
2262 &mod->num_ftrace_callsites);
2263#endif
2264#ifdef CONFIG_MODVERSIONS
2265 if ((mod->num_syms && !mod->crcs)
2266 || (mod->num_gpl_syms && !mod->gpl_crcs)
2267 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2268#ifdef CONFIG_UNUSED_SYMBOLS
2269 || (mod->num_unused_syms && !mod->unused_crcs)
2270 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2271#endif
2272 ) {
2273 err = try_to_force_load(mod,
2274 "no versions for exported symbols");
2275 if (err)
2276 goto cleanup;
2277 }
2278#endif
2279
2280 /* Now do relocations. */
2281 for (i = 1; i < hdr->e_shnum; i++) {
2282 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2283 unsigned int info = sechdrs[i].sh_info;
2284
2285 /* Not a valid relocation section? */
2286 if (info >= hdr->e_shnum)
2287 continue;
2288
2289 /* Don't bother with non-allocated sections */
2290 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2291 continue;
2292
2293 if (sechdrs[i].sh_type == SHT_REL)
2294 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2295 else if (sechdrs[i].sh_type == SHT_RELA)
2296 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2297 mod);
2298 if (err < 0)
2299 goto cleanup;
2300 }
2301
2302 /* Find duplicate symbols */
2303 err = verify_export_symbols(mod);
2304 if (err < 0)
2305 goto cleanup;
2306
2307 /* Set up and sort exception table */
2308 mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
2309 sizeof(*mod->extable), &mod->num_exentries);
2310 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2311
2312 /* Finally, copy percpu area over. */
2313 percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
2314 sechdrs[pcpuindex].sh_size);
2315
2316 add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex,
2317 symoffs, stroffs, secstrings, strmap);
2318 kfree(strmap);
2319 strmap = NULL;
2320
2321 if (!mod->taints) {
2322 struct _ddebug *debug;
2323 unsigned int num_debug;
2324
2325 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2326 sizeof(*debug), &num_debug);
2327 if (debug)
2328 dynamic_debug_setup(debug, num_debug);
2329 }
2330
2331 err = module_finalize(hdr, sechdrs, mod);
2332 if (err < 0)
2333 goto cleanup;
2334
2335 /* flush the icache in correct context */
2336 old_fs = get_fs();
2337 set_fs(KERNEL_DS);
2338
2339 /*
2340 * Flush the instruction cache, since we've played with text.
2341 * Do it before processing of module parameters, so the module
2342 * can provide parameter accessor functions of its own.
2343 */
2344 if (mod->module_init)
2345 flush_icache_range((unsigned long)mod->module_init,
2346 (unsigned long)mod->module_init
2347 + mod->init_size);
2348 flush_icache_range((unsigned long)mod->module_core,
2349 (unsigned long)mod->module_core + mod->core_size);
2350
2351 set_fs(old_fs);
2352
2353 mod->args = args;
2354 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2355 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2356 mod->name);
2357
2358 /* Now sew it into the lists so we can get lockdep and oops
2359 * info during argument parsing. Noone should access us, since
2360 * strong_try_module_get() will fail.
2361 * lockdep/oops can run asynchronous, so use the RCU list insertion
2362 * function to insert in a way safe to concurrent readers.
2363 * The mutex protects against concurrent writers.
2364 */
2365 list_add_rcu(&mod->list, &modules);
2366
2367 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2368 if (err < 0)
2369 goto unlink;
2370
2371 err = mod_sysfs_setup(mod, mod->kp, mod->num_kp);
2372 if (err < 0)
2373 goto unlink;
2374 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2375 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2376
2377 /* Get rid of temporary copy */
2378 vfree(hdr);
2379
2380 trace_module_load(mod);
2381
2382 /* Done! */
2383 return mod;
2384
2385 unlink:
2386 /* Unlink carefully: kallsyms could be walking list. */
2387 list_del_rcu(&mod->list);
2388 synchronize_sched();
2389 module_arch_cleanup(mod);
2390 cleanup:
2391 free_modinfo(mod);
2392 kobject_del(&mod->mkobj.kobj);
2393 kobject_put(&mod->mkobj.kobj);
2394 free_unload:
2395 module_unload_free(mod);
2396#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
2397 percpu_modfree(mod->refptr);
2398 free_init:
2399#endif
2400 module_free(mod, mod->module_init);
2401 free_core:
2402 module_free(mod, mod->module_core);
2403 /* mod will be freed with core. Don't access it beyond this line! */
2404 free_percpu:
2405 if (percpu)
2406 percpu_modfree(percpu);
2407 free_mod:
2408 kfree(args);
2409 kfree(strmap);
2410 free_hdr:
2411 vfree(hdr);
2412 return ERR_PTR(err);
2413
2414 truncated:
2415 printk(KERN_ERR "Module len %lu truncated\n", len);
2416 err = -ENOEXEC;
2417 goto free_hdr;
2418}
2419
2420/* Call module constructors. */
2421static void do_mod_ctors(struct module *mod)
2422{
2423#ifdef CONFIG_CONSTRUCTORS
2424 unsigned long i;
2425
2426 for (i = 0; i < mod->num_ctors; i++)
2427 mod->ctors[i]();
2428#endif
2429}
2430
2431/* This is where the real work happens */
2432SYSCALL_DEFINE3(init_module, void __user *, umod,
2433 unsigned long, len, const char __user *, uargs)
2434{
2435 struct module *mod;
2436 int ret = 0;
2437
2438 /* Must have permission */
2439 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2440 return -EPERM;
2441
2442 /* Only one module load at a time, please */
2443 if (mutex_lock_interruptible(&module_mutex) != 0)
2444 return -EINTR;
2445
2446 /* Do all the hard work */
2447 mod = load_module(umod, len, uargs);
2448 if (IS_ERR(mod)) {
2449 mutex_unlock(&module_mutex);
2450 return PTR_ERR(mod);
2451 }
2452
2453 /* Drop lock so they can recurse */
2454 mutex_unlock(&module_mutex);
2455
2456 blocking_notifier_call_chain(&module_notify_list,
2457 MODULE_STATE_COMING, mod);
2458
2459 do_mod_ctors(mod);
2460 /* Start the module */
2461 if (mod->init != NULL)
2462 ret = do_one_initcall(mod->init);
2463 if (ret < 0) {
2464 /* Init routine failed: abort. Try to protect us from
2465 buggy refcounters. */
2466 mod->state = MODULE_STATE_GOING;
2467 synchronize_sched();
2468 module_put(mod);
2469 blocking_notifier_call_chain(&module_notify_list,
2470 MODULE_STATE_GOING, mod);
2471 mutex_lock(&module_mutex);
2472 free_module(mod);
2473 mutex_unlock(&module_mutex);
2474 wake_up(&module_wq);
2475 return ret;
2476 }
2477 if (ret > 0) {
2478 printk(KERN_WARNING
2479"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2480"%s: loading module anyway...\n",
2481 __func__, mod->name, ret,
2482 __func__);
2483 dump_stack();
2484 }
2485
2486 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2487 mod->state = MODULE_STATE_LIVE;
2488 wake_up(&module_wq);
2489 blocking_notifier_call_chain(&module_notify_list,
2490 MODULE_STATE_LIVE, mod);
2491
2492 /* We need to finish all async code before the module init sequence is done */
2493 async_synchronize_full();
2494
2495 mutex_lock(&module_mutex);
2496 /* Drop initial reference. */
2497 module_put(mod);
2498 trim_init_extable(mod);
2499#ifdef CONFIG_KALLSYMS
2500 mod->num_symtab = mod->core_num_syms;
2501 mod->symtab = mod->core_symtab;
2502 mod->strtab = mod->core_strtab;
2503#endif
2504 module_free(mod, mod->module_init);
2505 mod->module_init = NULL;
2506 mod->init_size = 0;
2507 mod->init_text_size = 0;
2508 mutex_unlock(&module_mutex);
2509
2510 return 0;
2511}
2512
2513static inline int within(unsigned long addr, void *start, unsigned long size)
2514{
2515 return ((void *)addr >= start && (void *)addr < start + size);
2516}
2517
2518#ifdef CONFIG_KALLSYMS
2519/*
2520 * This ignores the intensely annoying "mapping symbols" found
2521 * in ARM ELF files: $a, $t and $d.
2522 */
2523static inline int is_arm_mapping_symbol(const char *str)
2524{
2525 return str[0] == '$' && strchr("atd", str[1])
2526 && (str[2] == '\0' || str[2] == '.');
2527}
2528
2529static const char *get_ksymbol(struct module *mod,
2530 unsigned long addr,
2531 unsigned long *size,
2532 unsigned long *offset)
2533{
2534 unsigned int i, best = 0;
2535 unsigned long nextval;
2536
2537 /* At worse, next value is at end of module */
2538 if (within_module_init(addr, mod))
2539 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2540 else
2541 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2542
2543 /* Scan for closest preceeding symbol, and next symbol. (ELF
2544 starts real symbols at 1). */
2545 for (i = 1; i < mod->num_symtab; i++) {
2546 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2547 continue;
2548
2549 /* We ignore unnamed symbols: they're uninformative
2550 * and inserted at a whim. */
2551 if (mod->symtab[i].st_value <= addr
2552 && mod->symtab[i].st_value > mod->symtab[best].st_value
2553 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2554 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2555 best = i;
2556 if (mod->symtab[i].st_value > addr
2557 && mod->symtab[i].st_value < nextval
2558 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2559 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2560 nextval = mod->symtab[i].st_value;
2561 }
2562
2563 if (!best)
2564 return NULL;
2565
2566 if (size)
2567 *size = nextval - mod->symtab[best].st_value;
2568 if (offset)
2569 *offset = addr - mod->symtab[best].st_value;
2570 return mod->strtab + mod->symtab[best].st_name;
2571}
2572
2573/* For kallsyms to ask for address resolution. NULL means not found. Careful
2574 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2575const char *module_address_lookup(unsigned long addr,
2576 unsigned long *size,
2577 unsigned long *offset,
2578 char **modname,
2579 char *namebuf)
2580{
2581 struct module *mod;
2582 const char *ret = NULL;
2583
2584 preempt_disable();
2585 list_for_each_entry_rcu(mod, &modules, list) {
2586 if (within_module_init(addr, mod) ||
2587 within_module_core(addr, mod)) {
2588 if (modname)
2589 *modname = mod->name;
2590 ret = get_ksymbol(mod, addr, size, offset);
2591 break;
2592 }
2593 }
2594 /* Make a copy in here where it's safe */
2595 if (ret) {
2596 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2597 ret = namebuf;
2598 }
2599 preempt_enable();
2600 return ret;
2601}
2602
2603int lookup_module_symbol_name(unsigned long addr, char *symname)
2604{
2605 struct module *mod;
2606
2607 preempt_disable();
2608 list_for_each_entry_rcu(mod, &modules, list) {
2609 if (within_module_init(addr, mod) ||
2610 within_module_core(addr, mod)) {
2611 const char *sym;
2612
2613 sym = get_ksymbol(mod, addr, NULL, NULL);
2614 if (!sym)
2615 goto out;
2616 strlcpy(symname, sym, KSYM_NAME_LEN);
2617 preempt_enable();
2618 return 0;
2619 }
2620 }
2621out:
2622 preempt_enable();
2623 return -ERANGE;
2624}
2625
2626int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2627 unsigned long *offset, char *modname, char *name)
2628{
2629 struct module *mod;
2630
2631 preempt_disable();
2632 list_for_each_entry_rcu(mod, &modules, list) {
2633 if (within_module_init(addr, mod) ||
2634 within_module_core(addr, mod)) {
2635 const char *sym;
2636
2637 sym = get_ksymbol(mod, addr, size, offset);
2638 if (!sym)
2639 goto out;
2640 if (modname)
2641 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2642 if (name)
2643 strlcpy(name, sym, KSYM_NAME_LEN);
2644 preempt_enable();
2645 return 0;
2646 }
2647 }
2648out:
2649 preempt_enable();
2650 return -ERANGE;
2651}
2652
2653int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2654 char *name, char *module_name, int *exported)
2655{
2656 struct module *mod;
2657
2658 preempt_disable();
2659 list_for_each_entry_rcu(mod, &modules, list) {
2660 if (symnum < mod->num_symtab) {
2661 *value = mod->symtab[symnum].st_value;
2662 *type = mod->symtab[symnum].st_info;
2663 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2664 KSYM_NAME_LEN);
2665 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2666 *exported = is_exported(name, *value, mod);
2667 preempt_enable();
2668 return 0;
2669 }
2670 symnum -= mod->num_symtab;
2671 }
2672 preempt_enable();
2673 return -ERANGE;
2674}
2675
2676static unsigned long mod_find_symname(struct module *mod, const char *name)
2677{
2678 unsigned int i;
2679
2680 for (i = 0; i < mod->num_symtab; i++)
2681 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2682 mod->symtab[i].st_info != 'U')
2683 return mod->symtab[i].st_value;
2684 return 0;
2685}
2686
2687/* Look for this name: can be of form module:name. */
2688unsigned long module_kallsyms_lookup_name(const char *name)
2689{
2690 struct module *mod;
2691 char *colon;
2692 unsigned long ret = 0;
2693
2694 /* Don't lock: we're in enough trouble already. */
2695 preempt_disable();
2696 if ((colon = strchr(name, ':')) != NULL) {
2697 *colon = '\0';
2698 if ((mod = find_module(name)) != NULL)
2699 ret = mod_find_symname(mod, colon+1);
2700 *colon = ':';
2701 } else {
2702 list_for_each_entry_rcu(mod, &modules, list)
2703 if ((ret = mod_find_symname(mod, name)) != 0)
2704 break;
2705 }
2706 preempt_enable();
2707 return ret;
2708}
2709
2710int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
2711 struct module *, unsigned long),
2712 void *data)
2713{
2714 struct module *mod;
2715 unsigned int i;
2716 int ret;
2717
2718 list_for_each_entry(mod, &modules, list) {
2719 for (i = 0; i < mod->num_symtab; i++) {
2720 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
2721 mod, mod->symtab[i].st_value);
2722 if (ret != 0)
2723 return ret;
2724 }
2725 }
2726 return 0;
2727}
2728#endif /* CONFIG_KALLSYMS */
2729
2730static char *module_flags(struct module *mod, char *buf)
2731{
2732 int bx = 0;
2733
2734 if (mod->taints ||
2735 mod->state == MODULE_STATE_GOING ||
2736 mod->state == MODULE_STATE_COMING) {
2737 buf[bx++] = '(';
2738 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2739 buf[bx++] = 'P';
2740 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2741 buf[bx++] = 'F';
2742 if (mod->taints & (1 << TAINT_CRAP))
2743 buf[bx++] = 'C';
2744 /*
2745 * TAINT_FORCED_RMMOD: could be added.
2746 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2747 * apply to modules.
2748 */
2749
2750 /* Show a - for module-is-being-unloaded */
2751 if (mod->state == MODULE_STATE_GOING)
2752 buf[bx++] = '-';
2753 /* Show a + for module-is-being-loaded */
2754 if (mod->state == MODULE_STATE_COMING)
2755 buf[bx++] = '+';
2756 buf[bx++] = ')';
2757 }
2758 buf[bx] = '\0';
2759
2760 return buf;
2761}
2762
2763#ifdef CONFIG_PROC_FS
2764/* Called by the /proc file system to return a list of modules. */
2765static void *m_start(struct seq_file *m, loff_t *pos)
2766{
2767 mutex_lock(&module_mutex);
2768 return seq_list_start(&modules, *pos);
2769}
2770
2771static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2772{
2773 return seq_list_next(p, &modules, pos);
2774}
2775
2776static void m_stop(struct seq_file *m, void *p)
2777{
2778 mutex_unlock(&module_mutex);
2779}
2780
2781static int m_show(struct seq_file *m, void *p)
2782{
2783 struct module *mod = list_entry(p, struct module, list);
2784 char buf[8];
2785
2786 seq_printf(m, "%s %u",
2787 mod->name, mod->init_size + mod->core_size);
2788 print_unload_info(m, mod);
2789
2790 /* Informative for users. */
2791 seq_printf(m, " %s",
2792 mod->state == MODULE_STATE_GOING ? "Unloading":
2793 mod->state == MODULE_STATE_COMING ? "Loading":
2794 "Live");
2795 /* Used by oprofile and other similar tools. */
2796 seq_printf(m, " 0x%p", mod->module_core);
2797
2798 /* Taints info */
2799 if (mod->taints)
2800 seq_printf(m, " %s", module_flags(mod, buf));
2801
2802 seq_printf(m, "\n");
2803 return 0;
2804}
2805
2806/* Format: modulename size refcount deps address
2807
2808 Where refcount is a number or -, and deps is a comma-separated list
2809 of depends or -.
2810*/
2811static const struct seq_operations modules_op = {
2812 .start = m_start,
2813 .next = m_next,
2814 .stop = m_stop,
2815 .show = m_show
2816};
2817
2818static int modules_open(struct inode *inode, struct file *file)
2819{
2820 return seq_open(file, &modules_op);
2821}
2822
2823static const struct file_operations proc_modules_operations = {
2824 .open = modules_open,
2825 .read = seq_read,
2826 .llseek = seq_lseek,
2827 .release = seq_release,
2828};
2829
2830static int __init proc_modules_init(void)
2831{
2832 proc_create("modules", 0, NULL, &proc_modules_operations);
2833 return 0;
2834}
2835module_init(proc_modules_init);
2836#endif
2837
2838/* Given an address, look for it in the module exception tables. */
2839const struct exception_table_entry *search_module_extables(unsigned long addr)
2840{
2841 const struct exception_table_entry *e = NULL;
2842 struct module *mod;
2843
2844 preempt_disable();
2845 list_for_each_entry_rcu(mod, &modules, list) {
2846 if (mod->num_exentries == 0)
2847 continue;
2848
2849 e = search_extable(mod->extable,
2850 mod->extable + mod->num_exentries - 1,
2851 addr);
2852 if (e)
2853 break;
2854 }
2855 preempt_enable();
2856
2857 /* Now, if we found one, we are running inside it now, hence
2858 we cannot unload the module, hence no refcnt needed. */
2859 return e;
2860}
2861
2862/*
2863 * is_module_address - is this address inside a module?
2864 * @addr: the address to check.
2865 *
2866 * See is_module_text_address() if you simply want to see if the address
2867 * is code (not data).
2868 */
2869bool is_module_address(unsigned long addr)
2870{
2871 bool ret;
2872
2873 preempt_disable();
2874 ret = __module_address(addr) != NULL;
2875 preempt_enable();
2876
2877 return ret;
2878}
2879
2880/*
2881 * __module_address - get the module which contains an address.
2882 * @addr: the address.
2883 *
2884 * Must be called with preempt disabled or module mutex held so that
2885 * module doesn't get freed during this.
2886 */
2887struct module *__module_address(unsigned long addr)
2888{
2889 struct module *mod;
2890
2891 if (addr < module_addr_min || addr > module_addr_max)
2892 return NULL;
2893
2894 list_for_each_entry_rcu(mod, &modules, list)
2895 if (within_module_core(addr, mod)
2896 || within_module_init(addr, mod))
2897 return mod;
2898 return NULL;
2899}
2900EXPORT_SYMBOL_GPL(__module_address);
2901
2902/*
2903 * is_module_text_address - is this address inside module code?
2904 * @addr: the address to check.
2905 *
2906 * See is_module_address() if you simply want to see if the address is
2907 * anywhere in a module. See kernel_text_address() for testing if an
2908 * address corresponds to kernel or module code.
2909 */
2910bool is_module_text_address(unsigned long addr)
2911{
2912 bool ret;
2913
2914 preempt_disable();
2915 ret = __module_text_address(addr) != NULL;
2916 preempt_enable();
2917
2918 return ret;
2919}
2920
2921/*
2922 * __module_text_address - get the module whose code contains an address.
2923 * @addr: the address.
2924 *
2925 * Must be called with preempt disabled or module mutex held so that
2926 * module doesn't get freed during this.
2927 */
2928struct module *__module_text_address(unsigned long addr)
2929{
2930 struct module *mod = __module_address(addr);
2931 if (mod) {
2932 /* Make sure it's within the text section. */
2933 if (!within(addr, mod->module_init, mod->init_text_size)
2934 && !within(addr, mod->module_core, mod->core_text_size))
2935 mod = NULL;
2936 }
2937 return mod;
2938}
2939EXPORT_SYMBOL_GPL(__module_text_address);
2940
2941/* Don't grab lock, we're oopsing. */
2942void print_modules(void)
2943{
2944 struct module *mod;
2945 char buf[8];
2946
2947 printk(KERN_DEFAULT "Modules linked in:");
2948 /* Most callers should already have preempt disabled, but make sure */
2949 preempt_disable();
2950 list_for_each_entry_rcu(mod, &modules, list)
2951 printk(" %s%s", mod->name, module_flags(mod, buf));
2952 preempt_enable();
2953 if (last_unloaded_module[0])
2954 printk(" [last unloaded: %s]", last_unloaded_module);
2955 printk("\n");
2956}
2957
2958#ifdef CONFIG_MODVERSIONS
2959/* Generate the signature for all relevant module structures here.
2960 * If these change, we don't want to try to parse the module. */
2961void module_layout(struct module *mod,
2962 struct modversion_info *ver,
2963 struct kernel_param *kp,
2964 struct kernel_symbol *ks,
2965 struct tracepoint *tp)
2966{
2967}
2968EXPORT_SYMBOL(module_layout);
2969#endif
2970
2971#ifdef CONFIG_TRACEPOINTS
2972void module_update_tracepoints(void)
2973{
2974 struct module *mod;
2975
2976 mutex_lock(&module_mutex);
2977 list_for_each_entry(mod, &modules, list)
2978 if (!mod->taints)
2979 tracepoint_update_probe_range(mod->tracepoints,
2980 mod->tracepoints + mod->num_tracepoints);
2981 mutex_unlock(&module_mutex);
2982}
2983
2984/*
2985 * Returns 0 if current not found.
2986 * Returns 1 if current found.
2987 */
2988int module_get_iter_tracepoints(struct tracepoint_iter *iter)
2989{
2990 struct module *iter_mod;
2991 int found = 0;
2992
2993 mutex_lock(&module_mutex);
2994 list_for_each_entry(iter_mod, &modules, list) {
2995 if (!iter_mod->taints) {
2996 /*
2997 * Sorted module list
2998 */
2999 if (iter_mod < iter->module)
3000 continue;
3001 else if (iter_mod > iter->module)
3002 iter->tracepoint = NULL;
3003 found = tracepoint_get_iter_range(&iter->tracepoint,
3004 iter_mod->tracepoints,
3005 iter_mod->tracepoints
3006 + iter_mod->num_tracepoints);
3007 if (found) {
3008 iter->module = iter_mod;
3009 break;
3010 }
3011 }
3012 }
3013 mutex_unlock(&module_mutex);
3014 return found;
3015}
3016#endif