projects/linux·blob v2.6.35-rc4 · refs

3182 lines · 81.0 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
62#if 0
63#define DEBUGP printk
64#else
65#define DEBUGP(fmt , a...)
66#endif
67
68#ifndef ARCH_SHF_SMALL
69#define ARCH_SHF_SMALL 0
70#endif
71
72/* If this is set, the section belongs in the init part of the module */
73#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
74
75/*
76 * Mutex protects:
77 * 1) List of modules (also safely readable with preempt_disable),
78 * 2) module_use links,
79 * 3) module_addr_min/module_addr_max.
80 * (delete uses stop_machine/add uses RCU list operations). */
81DEFINE_MUTEX(module_mutex);
82EXPORT_SYMBOL_GPL(module_mutex);
83static LIST_HEAD(modules);
84#ifdef CONFIG_KGDB_KDB
85struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
86#endif /* CONFIG_KGDB_KDB */
87
88
89/* Block module loading/unloading? */
90int modules_disabled = 0;
91
92/* Waiting for a module to finish initializing? */
93static DECLARE_WAIT_QUEUE_HEAD(module_wq);
94
95static BLOCKING_NOTIFIER_HEAD(module_notify_list);
96
97/* Bounds of module allocation, for speeding __module_address.
98 * Protected by module_mutex. */
99static unsigned long module_addr_min = -1UL, module_addr_max = 0;
100
101int register_module_notifier(struct notifier_block * nb)
102{
103 return blocking_notifier_chain_register(&module_notify_list, nb);
104}
105EXPORT_SYMBOL(register_module_notifier);
106
107int unregister_module_notifier(struct notifier_block * nb)
108{
109 return blocking_notifier_chain_unregister(&module_notify_list, nb);
110}
111EXPORT_SYMBOL(unregister_module_notifier);
112
113/* We require a truly strong try_module_get(): 0 means failure due to
114 ongoing or failed initialization etc. */
115static inline int strong_try_module_get(struct module *mod)
116{
117 if (mod && mod->state == MODULE_STATE_COMING)
118 return -EBUSY;
119 if (try_module_get(mod))
120 return 0;
121 else
122 return -ENOENT;
123}
124
125static inline void add_taint_module(struct module *mod, unsigned flag)
126{
127 add_taint(flag);
128 mod->taints |= (1U << flag);
129}
130
131/*
132 * A thread that wants to hold a reference to a module only while it
133 * is running can call this to safely exit. nfsd and lockd use this.
134 */
135void __module_put_and_exit(struct module *mod, long code)
136{
137 module_put(mod);
138 do_exit(code);
139}
140EXPORT_SYMBOL(__module_put_and_exit);
141
142/* Find a module section: 0 means not found. */
143static unsigned int find_sec(Elf_Ehdr *hdr,
144 Elf_Shdr *sechdrs,
145 const char *secstrings,
146 const char *name)
147{
148 unsigned int i;
149
150 for (i = 1; i < hdr->e_shnum; i++)
151 /* Alloc bit cleared means "ignore it." */
152 if ((sechdrs[i].sh_flags & SHF_ALLOC)
153 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
154 return i;
155 return 0;
156}
157
158/* Find a module section, or NULL. */
159static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
160 const char *secstrings, const char *name)
161{
162 /* Section 0 has sh_addr 0. */
163 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
164}
165
166/* Find a module section, or NULL. Fill in number of "objects" in section. */
167static void *section_objs(Elf_Ehdr *hdr,
168 Elf_Shdr *sechdrs,
169 const char *secstrings,
170 const char *name,
171 size_t object_size,
172 unsigned int *num)
173{
174 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
175
176 /* Section 0 has sh_addr 0 and sh_size 0. */
177 *num = sechdrs[sec].sh_size / object_size;
178 return (void *)sechdrs[sec].sh_addr;
179}
180
181/* Provided by the linker */
182extern const struct kernel_symbol __start___ksymtab[];
183extern const struct kernel_symbol __stop___ksymtab[];
184extern const struct kernel_symbol __start___ksymtab_gpl[];
185extern const struct kernel_symbol __stop___ksymtab_gpl[];
186extern const struct kernel_symbol __start___ksymtab_gpl_future[];
187extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
188extern const unsigned long __start___kcrctab[];
189extern const unsigned long __start___kcrctab_gpl[];
190extern const unsigned long __start___kcrctab_gpl_future[];
191#ifdef CONFIG_UNUSED_SYMBOLS
192extern const struct kernel_symbol __start___ksymtab_unused[];
193extern const struct kernel_symbol __stop___ksymtab_unused[];
194extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
195extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
196extern const unsigned long __start___kcrctab_unused[];
197extern const unsigned long __start___kcrctab_unused_gpl[];
198#endif
199
200#ifndef CONFIG_MODVERSIONS
201#define symversion(base, idx) NULL
202#else
203#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
204#endif
205
206static bool each_symbol_in_section(const struct symsearch *arr,
207 unsigned int arrsize,
208 struct module *owner,
209 bool (*fn)(const struct symsearch *syms,
210 struct module *owner,
211 unsigned int symnum, void *data),
212 void *data)
213{
214 unsigned int i, j;
215
216 for (j = 0; j < arrsize; j++) {
217 for (i = 0; i < arr[j].stop - arr[j].start; i++)
218 if (fn(&arr[j], owner, i, data))
219 return true;
220 }
221
222 return false;
223}
224
225/* Returns true as soon as fn returns true, otherwise false. */
226bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
227 unsigned int symnum, void *data), void *data)
228{
229 struct module *mod;
230 const struct symsearch arr[] = {
231 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
232 NOT_GPL_ONLY, false },
233 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
234 __start___kcrctab_gpl,
235 GPL_ONLY, false },
236 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
237 __start___kcrctab_gpl_future,
238 WILL_BE_GPL_ONLY, false },
239#ifdef CONFIG_UNUSED_SYMBOLS
240 { __start___ksymtab_unused, __stop___ksymtab_unused,
241 __start___kcrctab_unused,
242 NOT_GPL_ONLY, true },
243 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
244 __start___kcrctab_unused_gpl,
245 GPL_ONLY, true },
246#endif
247 };
248
249 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
250 return true;
251
252 list_for_each_entry_rcu(mod, &modules, list) {
253 struct symsearch arr[] = {
254 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
255 NOT_GPL_ONLY, false },
256 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
257 mod->gpl_crcs,
258 GPL_ONLY, false },
259 { mod->gpl_future_syms,
260 mod->gpl_future_syms + mod->num_gpl_future_syms,
261 mod->gpl_future_crcs,
262 WILL_BE_GPL_ONLY, false },
263#ifdef CONFIG_UNUSED_SYMBOLS
264 { mod->unused_syms,
265 mod->unused_syms + mod->num_unused_syms,
266 mod->unused_crcs,
267 NOT_GPL_ONLY, true },
268 { mod->unused_gpl_syms,
269 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
270 mod->unused_gpl_crcs,
271 GPL_ONLY, true },
272#endif
273 };
274
275 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
276 return true;
277 }
278 return false;
279}
280EXPORT_SYMBOL_GPL(each_symbol);
281
282struct find_symbol_arg {
283 /* Input */
284 const char *name;
285 bool gplok;
286 bool warn;
287
288 /* Output */
289 struct module *owner;
290 const unsigned long *crc;
291 const struct kernel_symbol *sym;
292};
293
294static bool find_symbol_in_section(const struct symsearch *syms,
295 struct module *owner,
296 unsigned int symnum, void *data)
297{
298 struct find_symbol_arg *fsa = data;
299
300 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
301 return false;
302
303 if (!fsa->gplok) {
304 if (syms->licence == GPL_ONLY)
305 return false;
306 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
307 printk(KERN_WARNING "Symbol %s is being used "
308 "by a non-GPL module, which will not "
309 "be allowed in the future\n", fsa->name);
310 printk(KERN_WARNING "Please see the file "
311 "Documentation/feature-removal-schedule.txt "
312 "in the kernel source tree for more details.\n");
313 }
314 }
315
316#ifdef CONFIG_UNUSED_SYMBOLS
317 if (syms->unused && fsa->warn) {
318 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
319 "however this module is using it.\n", fsa->name);
320 printk(KERN_WARNING
321 "This symbol will go away in the future.\n");
322 printk(KERN_WARNING
323 "Please evalute if this is the right api to use and if "
324 "it really is, submit a report the linux kernel "
325 "mailinglist together with submitting your code for "
326 "inclusion.\n");
327 }
328#endif
329
330 fsa->owner = owner;
331 fsa->crc = symversion(syms->crcs, symnum);
332 fsa->sym = &syms->start[symnum];
333 return true;
334}
335
336/* Find a symbol and return it, along with, (optional) crc and
337 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
338const struct kernel_symbol *find_symbol(const char *name,
339 struct module **owner,
340 const unsigned long **crc,
341 bool gplok,
342 bool warn)
343{
344 struct find_symbol_arg fsa;
345
346 fsa.name = name;
347 fsa.gplok = gplok;
348 fsa.warn = warn;
349
350 if (each_symbol(find_symbol_in_section, &fsa)) {
351 if (owner)
352 *owner = fsa.owner;
353 if (crc)
354 *crc = fsa.crc;
355 return fsa.sym;
356 }
357
358 DEBUGP("Failed to find symbol %s\n", name);
359 return NULL;
360}
361EXPORT_SYMBOL_GPL(find_symbol);
362
363/* Search for module by name: must hold module_mutex. */
364struct module *find_module(const char *name)
365{
366 struct module *mod;
367
368 list_for_each_entry(mod, &modules, list) {
369 if (strcmp(mod->name, name) == 0)
370 return mod;
371 }
372 return NULL;
373}
374EXPORT_SYMBOL_GPL(find_module);
375
376#ifdef CONFIG_SMP
377
378static inline void __percpu *mod_percpu(struct module *mod)
379{
380 return mod->percpu;
381}
382
383static int percpu_modalloc(struct module *mod,
384 unsigned long size, unsigned long align)
385{
386 if (align > PAGE_SIZE) {
387 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
388 mod->name, align, PAGE_SIZE);
389 align = PAGE_SIZE;
390 }
391
392 mod->percpu = __alloc_reserved_percpu(size, align);
393 if (!mod->percpu) {
394 printk(KERN_WARNING
395 "Could not allocate %lu bytes percpu data\n", size);
396 return -ENOMEM;
397 }
398 mod->percpu_size = size;
399 return 0;
400}
401
402static void percpu_modfree(struct module *mod)
403{
404 free_percpu(mod->percpu);
405}
406
407static unsigned int find_pcpusec(Elf_Ehdr *hdr,
408 Elf_Shdr *sechdrs,
409 const char *secstrings)
410{
411 return find_sec(hdr, sechdrs, secstrings, ".data..percpu");
412}
413
414static void percpu_modcopy(struct module *mod,
415 const void *from, unsigned long size)
416{
417 int cpu;
418
419 for_each_possible_cpu(cpu)
420 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
421}
422
423/**
424 * is_module_percpu_address - test whether address is from module static percpu
425 * @addr: address to test
426 *
427 * Test whether @addr belongs to module static percpu area.
428 *
429 * RETURNS:
430 * %true if @addr is from module static percpu area
431 */
432bool is_module_percpu_address(unsigned long addr)
433{
434 struct module *mod;
435 unsigned int cpu;
436
437 preempt_disable();
438
439 list_for_each_entry_rcu(mod, &modules, list) {
440 if (!mod->percpu_size)
441 continue;
442 for_each_possible_cpu(cpu) {
443 void *start = per_cpu_ptr(mod->percpu, cpu);
444
445 if ((void *)addr >= start &&
446 (void *)addr < start + mod->percpu_size) {
447 preempt_enable();
448 return true;
449 }
450 }
451 }
452
453 preempt_enable();
454 return false;
455}
456
457#else /* ... !CONFIG_SMP */
458
459static inline void __percpu *mod_percpu(struct module *mod)
460{
461 return NULL;
462}
463static inline int percpu_modalloc(struct module *mod,
464 unsigned long size, unsigned long align)
465{
466 return -ENOMEM;
467}
468static inline void percpu_modfree(struct module *mod)
469{
470}
471static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
472 Elf_Shdr *sechdrs,
473 const char *secstrings)
474{
475 return 0;
476}
477static inline void percpu_modcopy(struct module *mod,
478 const void *from, unsigned long size)
479{
480 /* pcpusec should be 0, and size of that section should be 0. */
481 BUG_ON(size != 0);
482}
483bool is_module_percpu_address(unsigned long addr)
484{
485 return false;
486}
487
488#endif /* CONFIG_SMP */
489
490#define MODINFO_ATTR(field) \
491static void setup_modinfo_##field(struct module *mod, const char *s) \
492{ \
493 mod->field = kstrdup(s, GFP_KERNEL); \
494} \
495static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
496 struct module *mod, char *buffer) \
497{ \
498 return sprintf(buffer, "%s\n", mod->field); \
499} \
500static int modinfo_##field##_exists(struct module *mod) \
501{ \
502 return mod->field != NULL; \
503} \
504static void free_modinfo_##field(struct module *mod) \
505{ \
506 kfree(mod->field); \
507 mod->field = NULL; \
508} \
509static struct module_attribute modinfo_##field = { \
510 .attr = { .name = __stringify(field), .mode = 0444 }, \
511 .show = show_modinfo_##field, \
512 .setup = setup_modinfo_##field, \
513 .test = modinfo_##field##_exists, \
514 .free = free_modinfo_##field, \
515};
516
517MODINFO_ATTR(version);
518MODINFO_ATTR(srcversion);
519
520static char last_unloaded_module[MODULE_NAME_LEN+1];
521
522#ifdef CONFIG_MODULE_UNLOAD
523
524EXPORT_TRACEPOINT_SYMBOL(module_get);
525
526/* Init the unload section of the module. */
527static void module_unload_init(struct module *mod)
528{
529 int cpu;
530
531 INIT_LIST_HEAD(&mod->source_list);
532 INIT_LIST_HEAD(&mod->target_list);
533 for_each_possible_cpu(cpu) {
534 per_cpu_ptr(mod->refptr, cpu)->incs = 0;
535 per_cpu_ptr(mod->refptr, cpu)->decs = 0;
536 }
537
538 /* Hold reference count during initialization. */
539 __this_cpu_write(mod->refptr->incs, 1);
540 /* Backwards compatibility macros put refcount during init. */
541 mod->waiter = current;
542}
543
544/* Does a already use b? */
545static int already_uses(struct module *a, struct module *b)
546{
547 struct module_use *use;
548
549 list_for_each_entry(use, &b->source_list, source_list) {
550 if (use->source == a) {
551 DEBUGP("%s uses %s!\n", a->name, b->name);
552 return 1;
553 }
554 }
555 DEBUGP("%s does not use %s!\n", a->name, b->name);
556 return 0;
557}
558
559/*
560 * Module a uses b
561 * - we add 'a' as a "source", 'b' as a "target" of module use
562 * - the module_use is added to the list of 'b' sources (so
563 * 'b' can walk the list to see who sourced them), and of 'a'
564 * targets (so 'a' can see what modules it targets).
565 */
566static int add_module_usage(struct module *a, struct module *b)
567{
568 struct module_use *use;
569
570 DEBUGP("Allocating new usage for %s.\n", a->name);
571 use = kmalloc(sizeof(*use), GFP_ATOMIC);
572 if (!use) {
573 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
574 return -ENOMEM;
575 }
576
577 use->source = a;
578 use->target = b;
579 list_add(&use->source_list, &b->source_list);
580 list_add(&use->target_list, &a->target_list);
581 return 0;
582}
583
584/* Module a uses b: caller needs module_mutex() */
585int ref_module(struct module *a, struct module *b)
586{
587 int err;
588
589 if (b == NULL || already_uses(a, b))
590 return 0;
591
592 /* If module isn't available, we fail. */
593 err = strong_try_module_get(b);
594 if (err)
595 return err;
596
597 err = add_module_usage(a, b);
598 if (err) {
599 module_put(b);
600 return err;
601 }
602 return 0;
603}
604EXPORT_SYMBOL_GPL(ref_module);
605
606/* Clear the unload stuff of the module. */
607static void module_unload_free(struct module *mod)
608{
609 struct module_use *use, *tmp;
610
611 mutex_lock(&module_mutex);
612 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
613 struct module *i = use->target;
614 DEBUGP("%s unusing %s\n", mod->name, i->name);
615 module_put(i);
616 list_del(&use->source_list);
617 list_del(&use->target_list);
618 kfree(use);
619 }
620 mutex_unlock(&module_mutex);
621}
622
623#ifdef CONFIG_MODULE_FORCE_UNLOAD
624static inline int try_force_unload(unsigned int flags)
625{
626 int ret = (flags & O_TRUNC);
627 if (ret)
628 add_taint(TAINT_FORCED_RMMOD);
629 return ret;
630}
631#else
632static inline int try_force_unload(unsigned int flags)
633{
634 return 0;
635}
636#endif /* CONFIG_MODULE_FORCE_UNLOAD */
637
638struct stopref
639{
640 struct module *mod;
641 int flags;
642 int *forced;
643};
644
645/* Whole machine is stopped with interrupts off when this runs. */
646static int __try_stop_module(void *_sref)
647{
648 struct stopref *sref = _sref;
649
650 /* If it's not unused, quit unless we're forcing. */
651 if (module_refcount(sref->mod) != 0) {
652 if (!(*sref->forced = try_force_unload(sref->flags)))
653 return -EWOULDBLOCK;
654 }
655
656 /* Mark it as dying. */
657 sref->mod->state = MODULE_STATE_GOING;
658 return 0;
659}
660
661static int try_stop_module(struct module *mod, int flags, int *forced)
662{
663 if (flags & O_NONBLOCK) {
664 struct stopref sref = { mod, flags, forced };
665
666 return stop_machine(__try_stop_module, &sref, NULL);
667 } else {
668 /* We don't need to stop the machine for this. */
669 mod->state = MODULE_STATE_GOING;
670 synchronize_sched();
671 return 0;
672 }
673}
674
675unsigned int module_refcount(struct module *mod)
676{
677 unsigned int incs = 0, decs = 0;
678 int cpu;
679
680 for_each_possible_cpu(cpu)
681 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
682 /*
683 * ensure the incs are added up after the decs.
684 * module_put ensures incs are visible before decs with smp_wmb.
685 *
686 * This 2-count scheme avoids the situation where the refcount
687 * for CPU0 is read, then CPU0 increments the module refcount,
688 * then CPU1 drops that refcount, then the refcount for CPU1 is
689 * read. We would record a decrement but not its corresponding
690 * increment so we would see a low count (disaster).
691 *
692 * Rare situation? But module_refcount can be preempted, and we
693 * might be tallying up 4096+ CPUs. So it is not impossible.
694 */
695 smp_rmb();
696 for_each_possible_cpu(cpu)
697 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
698 return incs - decs;
699}
700EXPORT_SYMBOL(module_refcount);
701
702/* This exists whether we can unload or not */
703static void free_module(struct module *mod);
704
705static void wait_for_zero_refcount(struct module *mod)
706{
707 /* Since we might sleep for some time, release the mutex first */
708 mutex_unlock(&module_mutex);
709 for (;;) {
710 DEBUGP("Looking at refcount...\n");
711 set_current_state(TASK_UNINTERRUPTIBLE);
712 if (module_refcount(mod) == 0)
713 break;
714 schedule();
715 }
716 current->state = TASK_RUNNING;
717 mutex_lock(&module_mutex);
718}
719
720SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
721 unsigned int, flags)
722{
723 struct module *mod;
724 char name[MODULE_NAME_LEN];
725 int ret, forced = 0;
726
727 if (!capable(CAP_SYS_MODULE) || modules_disabled)
728 return -EPERM;
729
730 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
731 return -EFAULT;
732 name[MODULE_NAME_LEN-1] = '\0';
733
734 if (mutex_lock_interruptible(&module_mutex) != 0)
735 return -EINTR;
736
737 mod = find_module(name);
738 if (!mod) {
739 ret = -ENOENT;
740 goto out;
741 }
742
743 if (!list_empty(&mod->source_list)) {
744 /* Other modules depend on us: get rid of them first. */
745 ret = -EWOULDBLOCK;
746 goto out;
747 }
748
749 /* Doing init or already dying? */
750 if (mod->state != MODULE_STATE_LIVE) {
751 /* FIXME: if (force), slam module count and wake up
752 waiter --RR */
753 DEBUGP("%s already dying\n", mod->name);
754 ret = -EBUSY;
755 goto out;
756 }
757
758 /* If it has an init func, it must have an exit func to unload */
759 if (mod->init && !mod->exit) {
760 forced = try_force_unload(flags);
761 if (!forced) {
762 /* This module can't be removed */
763 ret = -EBUSY;
764 goto out;
765 }
766 }
767
768 /* Set this up before setting mod->state */
769 mod->waiter = current;
770
771 /* Stop the machine so refcounts can't move and disable module. */
772 ret = try_stop_module(mod, flags, &forced);
773 if (ret != 0)
774 goto out;
775
776 /* Never wait if forced. */
777 if (!forced && module_refcount(mod) != 0)
778 wait_for_zero_refcount(mod);
779
780 mutex_unlock(&module_mutex);
781 /* Final destruction now noone is using it. */
782 if (mod->exit != NULL)
783 mod->exit();
784 blocking_notifier_call_chain(&module_notify_list,
785 MODULE_STATE_GOING, mod);
786 async_synchronize_full();
787
788 /* Store the name of the last unloaded module for diagnostic purposes */
789 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
790 ddebug_remove_module(mod->name);
791
792 free_module(mod);
793 return 0;
794out:
795 mutex_unlock(&module_mutex);
796 return ret;
797}
798
799static inline void print_unload_info(struct seq_file *m, struct module *mod)
800{
801 struct module_use *use;
802 int printed_something = 0;
803
804 seq_printf(m, " %u ", module_refcount(mod));
805
806 /* Always include a trailing , so userspace can differentiate
807 between this and the old multi-field proc format. */
808 list_for_each_entry(use, &mod->source_list, source_list) {
809 printed_something = 1;
810 seq_printf(m, "%s,", use->source->name);
811 }
812
813 if (mod->init != NULL && mod->exit == NULL) {
814 printed_something = 1;
815 seq_printf(m, "[permanent],");
816 }
817
818 if (!printed_something)
819 seq_printf(m, "-");
820}
821
822void __symbol_put(const char *symbol)
823{
824 struct module *owner;
825
826 preempt_disable();
827 if (!find_symbol(symbol, &owner, NULL, true, false))
828 BUG();
829 module_put(owner);
830 preempt_enable();
831}
832EXPORT_SYMBOL(__symbol_put);
833
834/* Note this assumes addr is a function, which it currently always is. */
835void symbol_put_addr(void *addr)
836{
837 struct module *modaddr;
838 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
839
840 if (core_kernel_text(a))
841 return;
842
843 /* module_text_address is safe here: we're supposed to have reference
844 * to module from symbol_get, so it can't go away. */
845 modaddr = __module_text_address(a);
846 BUG_ON(!modaddr);
847 module_put(modaddr);
848}
849EXPORT_SYMBOL_GPL(symbol_put_addr);
850
851static ssize_t show_refcnt(struct module_attribute *mattr,
852 struct module *mod, char *buffer)
853{
854 return sprintf(buffer, "%u\n", module_refcount(mod));
855}
856
857static struct module_attribute refcnt = {
858 .attr = { .name = "refcnt", .mode = 0444 },
859 .show = show_refcnt,
860};
861
862void module_put(struct module *module)
863{
864 if (module) {
865 preempt_disable();
866 smp_wmb(); /* see comment in module_refcount */
867 __this_cpu_inc(module->refptr->decs);
868
869 trace_module_put(module, _RET_IP_);
870 /* Maybe they're waiting for us to drop reference? */
871 if (unlikely(!module_is_live(module)))
872 wake_up_process(module->waiter);
873 preempt_enable();
874 }
875}
876EXPORT_SYMBOL(module_put);
877
878#else /* !CONFIG_MODULE_UNLOAD */
879static inline void print_unload_info(struct seq_file *m, struct module *mod)
880{
881 /* We don't know the usage count, or what modules are using. */
882 seq_printf(m, " - -");
883}
884
885static inline void module_unload_free(struct module *mod)
886{
887}
888
889int ref_module(struct module *a, struct module *b)
890{
891 return strong_try_module_get(b);
892}
893EXPORT_SYMBOL_GPL(ref_module);
894
895static inline void module_unload_init(struct module *mod)
896{
897}
898#endif /* CONFIG_MODULE_UNLOAD */
899
900static ssize_t show_initstate(struct module_attribute *mattr,
901 struct module *mod, char *buffer)
902{
903 const char *state = "unknown";
904
905 switch (mod->state) {
906 case MODULE_STATE_LIVE:
907 state = "live";
908 break;
909 case MODULE_STATE_COMING:
910 state = "coming";
911 break;
912 case MODULE_STATE_GOING:
913 state = "going";
914 break;
915 }
916 return sprintf(buffer, "%s\n", state);
917}
918
919static struct module_attribute initstate = {
920 .attr = { .name = "initstate", .mode = 0444 },
921 .show = show_initstate,
922};
923
924static struct module_attribute *modinfo_attrs[] = {
925 &modinfo_version,
926 &modinfo_srcversion,
927 &initstate,
928#ifdef CONFIG_MODULE_UNLOAD
929 &refcnt,
930#endif
931 NULL,
932};
933
934static const char vermagic[] = VERMAGIC_STRING;
935
936static int try_to_force_load(struct module *mod, const char *reason)
937{
938#ifdef CONFIG_MODULE_FORCE_LOAD
939 if (!test_taint(TAINT_FORCED_MODULE))
940 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
941 mod->name, reason);
942 add_taint_module(mod, TAINT_FORCED_MODULE);
943 return 0;
944#else
945 return -ENOEXEC;
946#endif
947}
948
949#ifdef CONFIG_MODVERSIONS
950/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
951static unsigned long maybe_relocated(unsigned long crc,
952 const struct module *crc_owner)
953{
954#ifdef ARCH_RELOCATES_KCRCTAB
955 if (crc_owner == NULL)
956 return crc - (unsigned long)reloc_start;
957#endif
958 return crc;
959}
960
961static 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 unsigned int i, num_versions;
969 struct modversion_info *versions;
970
971 /* Exporting module didn't supply crcs? OK, we're already tainted. */
972 if (!crc)
973 return 1;
974
975 /* No versions at all? modprobe --force does this. */
976 if (versindex == 0)
977 return try_to_force_load(mod, symname) == 0;
978
979 versions = (void *) sechdrs[versindex].sh_addr;
980 num_versions = sechdrs[versindex].sh_size
981 / sizeof(struct modversion_info);
982
983 for (i = 0; i < num_versions; i++) {
984 if (strcmp(versions[i].name, symname) != 0)
985 continue;
986
987 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
988 return 1;
989 DEBUGP("Found checksum %lX vs module %lX\n",
990 maybe_relocated(*crc, crc_owner), versions[i].crc);
991 goto bad_version;
992 }
993
994 printk(KERN_WARNING "%s: no symbol version for %s\n",
995 mod->name, symname);
996 return 0;
997
998bad_version:
999 printk("%s: disagrees about version of symbol %s\n",
1000 mod->name, symname);
1001 return 0;
1002}
1003
1004static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1005 unsigned int versindex,
1006 struct module *mod)
1007{
1008 const unsigned long *crc;
1009
1010 /* Since this should be found in kernel (which can't be removed),
1011 * no locking is necessary. */
1012 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1013 &crc, true, false))
1014 BUG();
1015 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1016 NULL);
1017}
1018
1019/* First part is kernel version, which we ignore if module has crcs. */
1020static inline int same_magic(const char *amagic, const char *bmagic,
1021 bool has_crcs)
1022{
1023 if (has_crcs) {
1024 amagic += strcspn(amagic, " ");
1025 bmagic += strcspn(bmagic, " ");
1026 }
1027 return strcmp(amagic, bmagic) == 0;
1028}
1029#else
1030static inline int check_version(Elf_Shdr *sechdrs,
1031 unsigned int versindex,
1032 const char *symname,
1033 struct module *mod,
1034 const unsigned long *crc,
1035 const struct module *crc_owner)
1036{
1037 return 1;
1038}
1039
1040static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1041 unsigned int versindex,
1042 struct module *mod)
1043{
1044 return 1;
1045}
1046
1047static inline int same_magic(const char *amagic, const char *bmagic,
1048 bool has_crcs)
1049{
1050 return strcmp(amagic, bmagic) == 0;
1051}
1052#endif /* CONFIG_MODVERSIONS */
1053
1054/* Resolve a symbol for this module. I.e. if we find one, record usage. */
1055static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
1056 unsigned int versindex,
1057 const char *name,
1058 struct module *mod,
1059 char ownername[])
1060{
1061 struct module *owner;
1062 const struct kernel_symbol *sym;
1063 const unsigned long *crc;
1064 int err;
1065
1066 mutex_lock(&module_mutex);
1067 sym = find_symbol(name, &owner, &crc,
1068 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1069 if (!sym)
1070 goto unlock;
1071
1072 if (!check_version(sechdrs, versindex, name, mod, crc, owner)) {
1073 sym = ERR_PTR(-EINVAL);
1074 goto getname;
1075 }
1076
1077 err = ref_module(mod, owner);
1078 if (err) {
1079 sym = ERR_PTR(err);
1080 goto getname;
1081 }
1082
1083getname:
1084 /* We must make copy under the lock if we failed to get ref. */
1085 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1086unlock:
1087 mutex_unlock(&module_mutex);
1088 return sym;
1089}
1090
1091static const struct kernel_symbol *resolve_symbol_wait(Elf_Shdr *sechdrs,
1092 unsigned int versindex,
1093 const char *name,
1094 struct module *mod)
1095{
1096 const struct kernel_symbol *ksym;
1097 char ownername[MODULE_NAME_LEN];
1098
1099 if (wait_event_interruptible_timeout(module_wq,
1100 !IS_ERR(ksym = resolve_symbol(sechdrs, versindex, name,
1101 mod, ownername)) ||
1102 PTR_ERR(ksym) != -EBUSY,
1103 30 * HZ) <= 0) {
1104 printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
1105 mod->name, ownername);
1106 }
1107 return ksym;
1108}
1109
1110/*
1111 * /sys/module/foo/sections stuff
1112 * J. Corbet <[email protected]>
1113 */
1114#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1115
1116static inline bool sect_empty(const Elf_Shdr *sect)
1117{
1118 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1119}
1120
1121struct module_sect_attr
1122{
1123 struct module_attribute mattr;
1124 char *name;
1125 unsigned long address;
1126};
1127
1128struct module_sect_attrs
1129{
1130 struct attribute_group grp;
1131 unsigned int nsections;
1132 struct module_sect_attr attrs[0];
1133};
1134
1135static ssize_t module_sect_show(struct module_attribute *mattr,
1136 struct module *mod, char *buf)
1137{
1138 struct module_sect_attr *sattr =
1139 container_of(mattr, struct module_sect_attr, mattr);
1140 return sprintf(buf, "0x%lx\n", sattr->address);
1141}
1142
1143static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1144{
1145 unsigned int section;
1146
1147 for (section = 0; section < sect_attrs->nsections; section++)
1148 kfree(sect_attrs->attrs[section].name);
1149 kfree(sect_attrs);
1150}
1151
1152static void add_sect_attrs(struct module *mod, unsigned int nsect,
1153 char *secstrings, Elf_Shdr *sechdrs)
1154{
1155 unsigned int nloaded = 0, i, size[2];
1156 struct module_sect_attrs *sect_attrs;
1157 struct module_sect_attr *sattr;
1158 struct attribute **gattr;
1159
1160 /* Count loaded sections and allocate structures */
1161 for (i = 0; i < nsect; i++)
1162 if (!sect_empty(&sechdrs[i]))
1163 nloaded++;
1164 size[0] = ALIGN(sizeof(*sect_attrs)
1165 + nloaded * sizeof(sect_attrs->attrs[0]),
1166 sizeof(sect_attrs->grp.attrs[0]));
1167 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1168 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1169 if (sect_attrs == NULL)
1170 return;
1171
1172 /* Setup section attributes. */
1173 sect_attrs->grp.name = "sections";
1174 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1175
1176 sect_attrs->nsections = 0;
1177 sattr = &sect_attrs->attrs[0];
1178 gattr = &sect_attrs->grp.attrs[0];
1179 for (i = 0; i < nsect; i++) {
1180 if (sect_empty(&sechdrs[i]))
1181 continue;
1182 sattr->address = sechdrs[i].sh_addr;
1183 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1184 GFP_KERNEL);
1185 if (sattr->name == NULL)
1186 goto out;
1187 sect_attrs->nsections++;
1188 sysfs_attr_init(&sattr->mattr.attr);
1189 sattr->mattr.show = module_sect_show;
1190 sattr->mattr.store = NULL;
1191 sattr->mattr.attr.name = sattr->name;
1192 sattr->mattr.attr.mode = S_IRUGO;
1193 *(gattr++) = &(sattr++)->mattr.attr;
1194 }
1195 *gattr = NULL;
1196
1197 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1198 goto out;
1199
1200 mod->sect_attrs = sect_attrs;
1201 return;
1202 out:
1203 free_sect_attrs(sect_attrs);
1204}
1205
1206static void remove_sect_attrs(struct module *mod)
1207{
1208 if (mod->sect_attrs) {
1209 sysfs_remove_group(&mod->mkobj.kobj,
1210 &mod->sect_attrs->grp);
1211 /* We are positive that no one is using any sect attrs
1212 * at this point. Deallocate immediately. */
1213 free_sect_attrs(mod->sect_attrs);
1214 mod->sect_attrs = NULL;
1215 }
1216}
1217
1218/*
1219 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1220 */
1221
1222struct module_notes_attrs {
1223 struct kobject *dir;
1224 unsigned int notes;
1225 struct bin_attribute attrs[0];
1226};
1227
1228static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1229 struct bin_attribute *bin_attr,
1230 char *buf, loff_t pos, size_t count)
1231{
1232 /*
1233 * The caller checked the pos and count against our size.
1234 */
1235 memcpy(buf, bin_attr->private + pos, count);
1236 return count;
1237}
1238
1239static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1240 unsigned int i)
1241{
1242 if (notes_attrs->dir) {
1243 while (i-- > 0)
1244 sysfs_remove_bin_file(notes_attrs->dir,
1245 &notes_attrs->attrs[i]);
1246 kobject_put(notes_attrs->dir);
1247 }
1248 kfree(notes_attrs);
1249}
1250
1251static void add_notes_attrs(struct module *mod, unsigned int nsect,
1252 char *secstrings, Elf_Shdr *sechdrs)
1253{
1254 unsigned int notes, loaded, i;
1255 struct module_notes_attrs *notes_attrs;
1256 struct bin_attribute *nattr;
1257
1258 /* failed to create section attributes, so can't create notes */
1259 if (!mod->sect_attrs)
1260 return;
1261
1262 /* Count notes sections and allocate structures. */
1263 notes = 0;
1264 for (i = 0; i < nsect; i++)
1265 if (!sect_empty(&sechdrs[i]) &&
1266 (sechdrs[i].sh_type == SHT_NOTE))
1267 ++notes;
1268
1269 if (notes == 0)
1270 return;
1271
1272 notes_attrs = kzalloc(sizeof(*notes_attrs)
1273 + notes * sizeof(notes_attrs->attrs[0]),
1274 GFP_KERNEL);
1275 if (notes_attrs == NULL)
1276 return;
1277
1278 notes_attrs->notes = notes;
1279 nattr = &notes_attrs->attrs[0];
1280 for (loaded = i = 0; i < nsect; ++i) {
1281 if (sect_empty(&sechdrs[i]))
1282 continue;
1283 if (sechdrs[i].sh_type == SHT_NOTE) {
1284 sysfs_bin_attr_init(nattr);
1285 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1286 nattr->attr.mode = S_IRUGO;
1287 nattr->size = sechdrs[i].sh_size;
1288 nattr->private = (void *) sechdrs[i].sh_addr;
1289 nattr->read = module_notes_read;
1290 ++nattr;
1291 }
1292 ++loaded;
1293 }
1294
1295 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1296 if (!notes_attrs->dir)
1297 goto out;
1298
1299 for (i = 0; i < notes; ++i)
1300 if (sysfs_create_bin_file(notes_attrs->dir,
1301 &notes_attrs->attrs[i]))
1302 goto out;
1303
1304 mod->notes_attrs = notes_attrs;
1305 return;
1306
1307 out:
1308 free_notes_attrs(notes_attrs, i);
1309}
1310
1311static void remove_notes_attrs(struct module *mod)
1312{
1313 if (mod->notes_attrs)
1314 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1315}
1316
1317#else
1318
1319static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1320 char *sectstrings, Elf_Shdr *sechdrs)
1321{
1322}
1323
1324static inline void remove_sect_attrs(struct module *mod)
1325{
1326}
1327
1328static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1329 char *sectstrings, Elf_Shdr *sechdrs)
1330{
1331}
1332
1333static inline void remove_notes_attrs(struct module *mod)
1334{
1335}
1336#endif
1337
1338#ifdef CONFIG_SYSFS
1339static void add_usage_links(struct module *mod)
1340{
1341#ifdef CONFIG_MODULE_UNLOAD
1342 struct module_use *use;
1343 int nowarn;
1344
1345 mutex_lock(&module_mutex);
1346 list_for_each_entry(use, &mod->target_list, target_list) {
1347 nowarn = sysfs_create_link(use->target->holders_dir,
1348 &mod->mkobj.kobj, mod->name);
1349 }
1350 mutex_unlock(&module_mutex);
1351#endif
1352}
1353
1354static void del_usage_links(struct module *mod)
1355{
1356#ifdef CONFIG_MODULE_UNLOAD
1357 struct module_use *use;
1358
1359 mutex_lock(&module_mutex);
1360 list_for_each_entry(use, &mod->target_list, target_list)
1361 sysfs_remove_link(use->target->holders_dir, mod->name);
1362 mutex_unlock(&module_mutex);
1363#endif
1364}
1365
1366static int module_add_modinfo_attrs(struct module *mod)
1367{
1368 struct module_attribute *attr;
1369 struct module_attribute *temp_attr;
1370 int error = 0;
1371 int i;
1372
1373 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1374 (ARRAY_SIZE(modinfo_attrs) + 1)),
1375 GFP_KERNEL);
1376 if (!mod->modinfo_attrs)
1377 return -ENOMEM;
1378
1379 temp_attr = mod->modinfo_attrs;
1380 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1381 if (!attr->test ||
1382 (attr->test && attr->test(mod))) {
1383 memcpy(temp_attr, attr, sizeof(*temp_attr));
1384 sysfs_attr_init(&temp_attr->attr);
1385 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1386 ++temp_attr;
1387 }
1388 }
1389 return error;
1390}
1391
1392static void module_remove_modinfo_attrs(struct module *mod)
1393{
1394 struct module_attribute *attr;
1395 int i;
1396
1397 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1398 /* pick a field to test for end of list */
1399 if (!attr->attr.name)
1400 break;
1401 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1402 if (attr->free)
1403 attr->free(mod);
1404 }
1405 kfree(mod->modinfo_attrs);
1406}
1407
1408static int mod_sysfs_init(struct module *mod)
1409{
1410 int err;
1411 struct kobject *kobj;
1412
1413 if (!module_sysfs_initialized) {
1414 printk(KERN_ERR "%s: module sysfs not initialized\n",
1415 mod->name);
1416 err = -EINVAL;
1417 goto out;
1418 }
1419
1420 kobj = kset_find_obj(module_kset, mod->name);
1421 if (kobj) {
1422 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1423 kobject_put(kobj);
1424 err = -EINVAL;
1425 goto out;
1426 }
1427
1428 mod->mkobj.mod = mod;
1429
1430 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1431 mod->mkobj.kobj.kset = module_kset;
1432 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1433 "%s", mod->name);
1434 if (err)
1435 kobject_put(&mod->mkobj.kobj);
1436
1437 /* delay uevent until full sysfs population */
1438out:
1439 return err;
1440}
1441
1442static int mod_sysfs_setup(struct module *mod,
1443 struct kernel_param *kparam,
1444 unsigned int num_params)
1445{
1446 int err;
1447
1448 err = mod_sysfs_init(mod);
1449 if (err)
1450 goto out;
1451
1452 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1453 if (!mod->holders_dir) {
1454 err = -ENOMEM;
1455 goto out_unreg;
1456 }
1457
1458 err = module_param_sysfs_setup(mod, kparam, num_params);
1459 if (err)
1460 goto out_unreg_holders;
1461
1462 err = module_add_modinfo_attrs(mod);
1463 if (err)
1464 goto out_unreg_param;
1465
1466 add_usage_links(mod);
1467
1468 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1469 return 0;
1470
1471out_unreg_param:
1472 module_param_sysfs_remove(mod);
1473out_unreg_holders:
1474 kobject_put(mod->holders_dir);
1475out_unreg:
1476 kobject_put(&mod->mkobj.kobj);
1477out:
1478 return err;
1479}
1480
1481static void mod_sysfs_fini(struct module *mod)
1482{
1483 kobject_put(&mod->mkobj.kobj);
1484}
1485
1486#else /* CONFIG_SYSFS */
1487
1488static inline int mod_sysfs_init(struct module *mod)
1489{
1490 return 0;
1491}
1492
1493static inline int mod_sysfs_setup(struct module *mod,
1494 struct kernel_param *kparam,
1495 unsigned int num_params)
1496{
1497 return 0;
1498}
1499
1500static inline int module_add_modinfo_attrs(struct module *mod)
1501{
1502 return 0;
1503}
1504
1505static inline void module_remove_modinfo_attrs(struct module *mod)
1506{
1507}
1508
1509static void mod_sysfs_fini(struct module *mod)
1510{
1511}
1512
1513static void del_usage_links(struct module *mod)
1514{
1515}
1516
1517#endif /* CONFIG_SYSFS */
1518
1519static void mod_kobject_remove(struct module *mod)
1520{
1521 del_usage_links(mod);
1522 module_remove_modinfo_attrs(mod);
1523 module_param_sysfs_remove(mod);
1524 kobject_put(mod->mkobj.drivers_dir);
1525 kobject_put(mod->holders_dir);
1526 mod_sysfs_fini(mod);
1527}
1528
1529/*
1530 * unlink the module with the whole machine is stopped with interrupts off
1531 * - this defends against kallsyms not taking locks
1532 */
1533static int __unlink_module(void *_mod)
1534{
1535 struct module *mod = _mod;
1536 list_del(&mod->list);
1537 return 0;
1538}
1539
1540/* Free a module, remove from lists, etc. */
1541static void free_module(struct module *mod)
1542{
1543 trace_module_free(mod);
1544
1545 /* Delete from various lists */
1546 mutex_lock(&module_mutex);
1547 stop_machine(__unlink_module, mod, NULL);
1548 mutex_unlock(&module_mutex);
1549 remove_notes_attrs(mod);
1550 remove_sect_attrs(mod);
1551 mod_kobject_remove(mod);
1552
1553 /* Arch-specific cleanup. */
1554 module_arch_cleanup(mod);
1555
1556 /* Module unload stuff */
1557 module_unload_free(mod);
1558
1559 /* Free any allocated parameters. */
1560 destroy_params(mod->kp, mod->num_kp);
1561
1562 /* This may be NULL, but that's OK */
1563 module_free(mod, mod->module_init);
1564 kfree(mod->args);
1565 percpu_modfree(mod);
1566#if defined(CONFIG_MODULE_UNLOAD)
1567 if (mod->refptr)
1568 free_percpu(mod->refptr);
1569#endif
1570 /* Free lock-classes: */
1571 lockdep_free_key_range(mod->module_core, mod->core_size);
1572
1573 /* Finally, free the core (containing the module structure) */
1574 module_free(mod, mod->module_core);
1575
1576#ifdef CONFIG_MPU
1577 update_protections(current->mm);
1578#endif
1579}
1580
1581void *__symbol_get(const char *symbol)
1582{
1583 struct module *owner;
1584 const struct kernel_symbol *sym;
1585
1586 preempt_disable();
1587 sym = find_symbol(symbol, &owner, NULL, true, true);
1588 if (sym && strong_try_module_get(owner))
1589 sym = NULL;
1590 preempt_enable();
1591
1592 return sym ? (void *)sym->value : NULL;
1593}
1594EXPORT_SYMBOL_GPL(__symbol_get);
1595
1596/*
1597 * Ensure that an exported symbol [global namespace] does not already exist
1598 * in the kernel or in some other module's exported symbol table.
1599 *
1600 * You must hold the module_mutex.
1601 */
1602static int verify_export_symbols(struct module *mod)
1603{
1604 unsigned int i;
1605 struct module *owner;
1606 const struct kernel_symbol *s;
1607 struct {
1608 const struct kernel_symbol *sym;
1609 unsigned int num;
1610 } arr[] = {
1611 { mod->syms, mod->num_syms },
1612 { mod->gpl_syms, mod->num_gpl_syms },
1613 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1614#ifdef CONFIG_UNUSED_SYMBOLS
1615 { mod->unused_syms, mod->num_unused_syms },
1616 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1617#endif
1618 };
1619
1620 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1621 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1622 if (find_symbol(s->name, &owner, NULL, true, false)) {
1623 printk(KERN_ERR
1624 "%s: exports duplicate symbol %s"
1625 " (owned by %s)\n",
1626 mod->name, s->name, module_name(owner));
1627 return -ENOEXEC;
1628 }
1629 }
1630 }
1631 return 0;
1632}
1633
1634/* Change all symbols so that st_value encodes the pointer directly. */
1635static int simplify_symbols(Elf_Shdr *sechdrs,
1636 unsigned int symindex,
1637 const char *strtab,
1638 unsigned int versindex,
1639 unsigned int pcpuindex,
1640 struct module *mod)
1641{
1642 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1643 unsigned long secbase;
1644 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1645 int ret = 0;
1646 const struct kernel_symbol *ksym;
1647
1648 for (i = 1; i < n; i++) {
1649 switch (sym[i].st_shndx) {
1650 case SHN_COMMON:
1651 /* We compiled with -fno-common. These are not
1652 supposed to happen. */
1653 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1654 printk("%s: please compile with -fno-common\n",
1655 mod->name);
1656 ret = -ENOEXEC;
1657 break;
1658
1659 case SHN_ABS:
1660 /* Don't need to do anything */
1661 DEBUGP("Absolute symbol: 0x%08lx\n",
1662 (long)sym[i].st_value);
1663 break;
1664
1665 case SHN_UNDEF:
1666 ksym = resolve_symbol_wait(sechdrs, versindex,
1667 strtab + sym[i].st_name,
1668 mod);
1669 /* Ok if resolved. */
1670 if (ksym && !IS_ERR(ksym)) {
1671 sym[i].st_value = ksym->value;
1672 break;
1673 }
1674
1675 /* Ok if weak. */
1676 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1677 break;
1678
1679 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
1680 mod->name, strtab + sym[i].st_name,
1681 PTR_ERR(ksym));
1682 ret = PTR_ERR(ksym) ?: -ENOENT;
1683 break;
1684
1685 default:
1686 /* Divert to percpu allocation if a percpu var. */
1687 if (sym[i].st_shndx == pcpuindex)
1688 secbase = (unsigned long)mod_percpu(mod);
1689 else
1690 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1691 sym[i].st_value += secbase;
1692 break;
1693 }
1694 }
1695
1696 return ret;
1697}
1698
1699/* Additional bytes needed by arch in front of individual sections */
1700unsigned int __weak arch_mod_section_prepend(struct module *mod,
1701 unsigned int section)
1702{
1703 /* default implementation just returns zero */
1704 return 0;
1705}
1706
1707/* Update size with this section: return offset. */
1708static long get_offset(struct module *mod, unsigned int *size,
1709 Elf_Shdr *sechdr, unsigned int section)
1710{
1711 long ret;
1712
1713 *size += arch_mod_section_prepend(mod, section);
1714 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1715 *size = ret + sechdr->sh_size;
1716 return ret;
1717}
1718
1719/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1720 might -- code, read-only data, read-write data, small data. Tally
1721 sizes, and place the offsets into sh_entsize fields: high bit means it
1722 belongs in init. */
1723static void layout_sections(struct module *mod,
1724 const Elf_Ehdr *hdr,
1725 Elf_Shdr *sechdrs,
1726 const char *secstrings)
1727{
1728 static unsigned long const masks[][2] = {
1729 /* NOTE: all executable code must be the first section
1730 * in this array; otherwise modify the text_size
1731 * finder in the two loops below */
1732 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1733 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1734 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1735 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1736 };
1737 unsigned int m, i;
1738
1739 for (i = 0; i < hdr->e_shnum; i++)
1740 sechdrs[i].sh_entsize = ~0UL;
1741
1742 DEBUGP("Core section allocation order:\n");
1743 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1744 for (i = 0; i < hdr->e_shnum; ++i) {
1745 Elf_Shdr *s = &sechdrs[i];
1746
1747 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1748 || (s->sh_flags & masks[m][1])
1749 || s->sh_entsize != ~0UL
1750 || strstarts(secstrings + s->sh_name, ".init"))
1751 continue;
1752 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1753 DEBUGP("\t%s\n", secstrings + s->sh_name);
1754 }
1755 if (m == 0)
1756 mod->core_text_size = mod->core_size;
1757 }
1758
1759 DEBUGP("Init section allocation order:\n");
1760 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1761 for (i = 0; i < hdr->e_shnum; ++i) {
1762 Elf_Shdr *s = &sechdrs[i];
1763
1764 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1765 || (s->sh_flags & masks[m][1])
1766 || s->sh_entsize != ~0UL
1767 || !strstarts(secstrings + s->sh_name, ".init"))
1768 continue;
1769 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1770 | INIT_OFFSET_MASK);
1771 DEBUGP("\t%s\n", secstrings + s->sh_name);
1772 }
1773 if (m == 0)
1774 mod->init_text_size = mod->init_size;
1775 }
1776}
1777
1778static void set_license(struct module *mod, const char *license)
1779{
1780 if (!license)
1781 license = "unspecified";
1782
1783 if (!license_is_gpl_compatible(license)) {
1784 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1785 printk(KERN_WARNING "%s: module license '%s' taints "
1786 "kernel.\n", mod->name, license);
1787 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1788 }
1789}
1790
1791/* Parse tag=value strings from .modinfo section */
1792static char *next_string(char *string, unsigned long *secsize)
1793{
1794 /* Skip non-zero chars */
1795 while (string[0]) {
1796 string++;
1797 if ((*secsize)-- <= 1)
1798 return NULL;
1799 }
1800
1801 /* Skip any zero padding. */
1802 while (!string[0]) {
1803 string++;
1804 if ((*secsize)-- <= 1)
1805 return NULL;
1806 }
1807 return string;
1808}
1809
1810static char *get_modinfo(Elf_Shdr *sechdrs,
1811 unsigned int info,
1812 const char *tag)
1813{
1814 char *p;
1815 unsigned int taglen = strlen(tag);
1816 unsigned long size = sechdrs[info].sh_size;
1817
1818 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1819 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1820 return p + taglen + 1;
1821 }
1822 return NULL;
1823}
1824
1825static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1826 unsigned int infoindex)
1827{
1828 struct module_attribute *attr;
1829 int i;
1830
1831 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1832 if (attr->setup)
1833 attr->setup(mod,
1834 get_modinfo(sechdrs,
1835 infoindex,
1836 attr->attr.name));
1837 }
1838}
1839
1840static void free_modinfo(struct module *mod)
1841{
1842 struct module_attribute *attr;
1843 int i;
1844
1845 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1846 if (attr->free)
1847 attr->free(mod);
1848 }
1849}
1850
1851#ifdef CONFIG_KALLSYMS
1852
1853/* lookup symbol in given range of kernel_symbols */
1854static const struct kernel_symbol *lookup_symbol(const char *name,
1855 const struct kernel_symbol *start,
1856 const struct kernel_symbol *stop)
1857{
1858 const struct kernel_symbol *ks = start;
1859 for (; ks < stop; ks++)
1860 if (strcmp(ks->name, name) == 0)
1861 return ks;
1862 return NULL;
1863}
1864
1865static int is_exported(const char *name, unsigned long value,
1866 const struct module *mod)
1867{
1868 const struct kernel_symbol *ks;
1869 if (!mod)
1870 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1871 else
1872 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1873 return ks != NULL && ks->value == value;
1874}
1875
1876/* As per nm */
1877static char elf_type(const Elf_Sym *sym,
1878 Elf_Shdr *sechdrs,
1879 const char *secstrings,
1880 struct module *mod)
1881{
1882 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1883 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1884 return 'v';
1885 else
1886 return 'w';
1887 }
1888 if (sym->st_shndx == SHN_UNDEF)
1889 return 'U';
1890 if (sym->st_shndx == SHN_ABS)
1891 return 'a';
1892 if (sym->st_shndx >= SHN_LORESERVE)
1893 return '?';
1894 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1895 return 't';
1896 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1897 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1898 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1899 return 'r';
1900 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1901 return 'g';
1902 else
1903 return 'd';
1904 }
1905 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1906 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1907 return 's';
1908 else
1909 return 'b';
1910 }
1911 if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug"))
1912 return 'n';
1913 return '?';
1914}
1915
1916static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1917 unsigned int shnum)
1918{
1919 const Elf_Shdr *sec;
1920
1921 if (src->st_shndx == SHN_UNDEF
1922 || src->st_shndx >= shnum
1923 || !src->st_name)
1924 return false;
1925
1926 sec = sechdrs + src->st_shndx;
1927 if (!(sec->sh_flags & SHF_ALLOC)
1928#ifndef CONFIG_KALLSYMS_ALL
1929 || !(sec->sh_flags & SHF_EXECINSTR)
1930#endif
1931 || (sec->sh_entsize & INIT_OFFSET_MASK))
1932 return false;
1933
1934 return true;
1935}
1936
1937static unsigned long layout_symtab(struct module *mod,
1938 Elf_Shdr *sechdrs,
1939 unsigned int symindex,
1940 unsigned int strindex,
1941 const Elf_Ehdr *hdr,
1942 const char *secstrings,
1943 unsigned long *pstroffs,
1944 unsigned long *strmap)
1945{
1946 unsigned long symoffs;
1947 Elf_Shdr *symsect = sechdrs + symindex;
1948 Elf_Shdr *strsect = sechdrs + strindex;
1949 const Elf_Sym *src;
1950 const char *strtab;
1951 unsigned int i, nsrc, ndst;
1952
1953 /* Put symbol section at end of init part of module. */
1954 symsect->sh_flags |= SHF_ALLOC;
1955 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1956 symindex) | INIT_OFFSET_MASK;
1957 DEBUGP("\t%s\n", secstrings + symsect->sh_name);
1958
1959 src = (void *)hdr + symsect->sh_offset;
1960 nsrc = symsect->sh_size / sizeof(*src);
1961 strtab = (void *)hdr + strsect->sh_offset;
1962 for (ndst = i = 1; i < nsrc; ++i, ++src)
1963 if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
1964 unsigned int j = src->st_name;
1965
1966 while(!__test_and_set_bit(j, strmap) && strtab[j])
1967 ++j;
1968 ++ndst;
1969 }
1970
1971 /* Append room for core symbols at end of core part. */
1972 symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
1973 mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
1974
1975 /* Put string table section at end of init part of module. */
1976 strsect->sh_flags |= SHF_ALLOC;
1977 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
1978 strindex) | INIT_OFFSET_MASK;
1979 DEBUGP("\t%s\n", secstrings + strsect->sh_name);
1980
1981 /* Append room for core symbols' strings at end of core part. */
1982 *pstroffs = mod->core_size;
1983 __set_bit(0, strmap);
1984 mod->core_size += bitmap_weight(strmap, strsect->sh_size);
1985
1986 return symoffs;
1987}
1988
1989static void add_kallsyms(struct module *mod,
1990 Elf_Shdr *sechdrs,
1991 unsigned int shnum,
1992 unsigned int symindex,
1993 unsigned int strindex,
1994 unsigned long symoffs,
1995 unsigned long stroffs,
1996 const char *secstrings,
1997 unsigned long *strmap)
1998{
1999 unsigned int i, ndst;
2000 const Elf_Sym *src;
2001 Elf_Sym *dst;
2002 char *s;
2003
2004 mod->symtab = (void *)sechdrs[symindex].sh_addr;
2005 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
2006 mod->strtab = (void *)sechdrs[strindex].sh_addr;
2007
2008 /* Set types up while we still have access to sections. */
2009 for (i = 0; i < mod->num_symtab; i++)
2010 mod->symtab[i].st_info
2011 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
2012
2013 mod->core_symtab = dst = mod->module_core + symoffs;
2014 src = mod->symtab;
2015 *dst = *src;
2016 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
2017 if (!is_core_symbol(src, sechdrs, shnum))
2018 continue;
2019 dst[ndst] = *src;
2020 dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
2021 ++ndst;
2022 }
2023 mod->core_num_syms = ndst;
2024
2025 mod->core_strtab = s = mod->module_core + stroffs;
2026 for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i)
2027 if (test_bit(i, strmap))
2028 *++s = mod->strtab[i];
2029}
2030#else
2031static inline unsigned long layout_symtab(struct module *mod,
2032 Elf_Shdr *sechdrs,
2033 unsigned int symindex,
2034 unsigned int strindex,
2035 const Elf_Ehdr *hdr,
2036 const char *secstrings,
2037 unsigned long *pstroffs,
2038 unsigned long *strmap)
2039{
2040 return 0;
2041}
2042
2043static inline void add_kallsyms(struct module *mod,
2044 Elf_Shdr *sechdrs,
2045 unsigned int shnum,
2046 unsigned int symindex,
2047 unsigned int strindex,
2048 unsigned long symoffs,
2049 unsigned long stroffs,
2050 const char *secstrings,
2051 const unsigned long *strmap)
2052{
2053}
2054#endif /* CONFIG_KALLSYMS */
2055
2056static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2057{
2058#ifdef CONFIG_DYNAMIC_DEBUG
2059 if (ddebug_add_module(debug, num, debug->modname))
2060 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2061 debug->modname);
2062#endif
2063}
2064
2065static void dynamic_debug_remove(struct _ddebug *debug)
2066{
2067 if (debug)
2068 ddebug_remove_module(debug->modname);
2069}
2070
2071static void *module_alloc_update_bounds(unsigned long size)
2072{
2073 void *ret = module_alloc(size);
2074
2075 if (ret) {
2076 mutex_lock(&module_mutex);
2077 /* Update module bounds. */
2078 if ((unsigned long)ret < module_addr_min)
2079 module_addr_min = (unsigned long)ret;
2080 if ((unsigned long)ret + size > module_addr_max)
2081 module_addr_max = (unsigned long)ret + size;
2082 mutex_unlock(&module_mutex);
2083 }
2084 return ret;
2085}
2086
2087#ifdef CONFIG_DEBUG_KMEMLEAK
2088static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2089 Elf_Shdr *sechdrs, char *secstrings)
2090{
2091 unsigned int i;
2092
2093 /* only scan the sections containing data */
2094 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2095
2096 for (i = 1; i < hdr->e_shnum; i++) {
2097 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2098 continue;
2099 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
2100 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
2101 continue;
2102
2103 kmemleak_scan_area((void *)sechdrs[i].sh_addr,
2104 sechdrs[i].sh_size, GFP_KERNEL);
2105 }
2106}
2107#else
2108static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2109 Elf_Shdr *sechdrs, char *secstrings)
2110{
2111}
2112#endif
2113
2114/* Allocate and load the module: note that size of section 0 is always
2115 zero, and we rely on this for optional sections. */
2116static noinline struct module *load_module(void __user *umod,
2117 unsigned long len,
2118 const char __user *uargs)
2119{
2120 Elf_Ehdr *hdr;
2121 Elf_Shdr *sechdrs;
2122 char *secstrings, *args, *modmagic, *strtab = NULL;
2123 char *staging;
2124 unsigned int i;
2125 unsigned int symindex = 0;
2126 unsigned int strindex = 0;
2127 unsigned int modindex, versindex, infoindex, pcpuindex;
2128 struct module *mod;
2129 long err = 0;
2130 void *ptr = NULL; /* Stops spurious gcc warning */
2131 unsigned long symoffs, stroffs, *strmap;
2132 void __percpu *percpu;
2133 struct _ddebug *debug = NULL;
2134 unsigned int num_debug = 0;
2135
2136 mm_segment_t old_fs;
2137
2138 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2139 umod, len, uargs);
2140 if (len < sizeof(*hdr))
2141 return ERR_PTR(-ENOEXEC);
2142
2143 /* Suck in entire file: we'll want most of it. */
2144 /* vmalloc barfs on "unusual" numbers. Check here */
2145 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
2146 return ERR_PTR(-ENOMEM);
2147
2148 if (copy_from_user(hdr, umod, len) != 0) {
2149 err = -EFAULT;
2150 goto free_hdr;
2151 }
2152
2153 /* Sanity checks against insmoding binaries or wrong arch,
2154 weird elf version */
2155 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
2156 || hdr->e_type != ET_REL
2157 || !elf_check_arch(hdr)
2158 || hdr->e_shentsize != sizeof(*sechdrs)) {
2159 err = -ENOEXEC;
2160 goto free_hdr;
2161 }
2162
2163 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
2164 goto truncated;
2165
2166 /* Convenience variables */
2167 sechdrs = (void *)hdr + hdr->e_shoff;
2168 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
2169 sechdrs[0].sh_addr = 0;
2170
2171 for (i = 1; i < hdr->e_shnum; i++) {
2172 if (sechdrs[i].sh_type != SHT_NOBITS
2173 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
2174 goto truncated;
2175
2176 /* Mark all sections sh_addr with their address in the
2177 temporary image. */
2178 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
2179
2180 /* Internal symbols and strings. */
2181 if (sechdrs[i].sh_type == SHT_SYMTAB) {
2182 symindex = i;
2183 strindex = sechdrs[i].sh_link;
2184 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
2185 }
2186#ifndef CONFIG_MODULE_UNLOAD
2187 /* Don't load .exit sections */
2188 if (strstarts(secstrings+sechdrs[i].sh_name, ".exit"))
2189 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
2190#endif
2191 }
2192
2193 modindex = find_sec(hdr, sechdrs, secstrings,
2194 ".gnu.linkonce.this_module");
2195 if (!modindex) {
2196 printk(KERN_WARNING "No module found in object\n");
2197 err = -ENOEXEC;
2198 goto free_hdr;
2199 }
2200 /* This is temporary: point mod into copy of data. */
2201 mod = (void *)sechdrs[modindex].sh_addr;
2202
2203 if (symindex == 0) {
2204 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2205 mod->name);
2206 err = -ENOEXEC;
2207 goto free_hdr;
2208 }
2209
2210 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
2211 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
2212 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
2213
2214 /* Don't keep modinfo and version sections. */
2215 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2216 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2217
2218 /* Check module struct version now, before we try to use module. */
2219 if (!check_modstruct_version(sechdrs, versindex, mod)) {
2220 err = -ENOEXEC;
2221 goto free_hdr;
2222 }
2223
2224 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2225 /* This is allowed: modprobe --force will invalidate it. */
2226 if (!modmagic) {
2227 err = try_to_force_load(mod, "bad vermagic");
2228 if (err)
2229 goto free_hdr;
2230 } else if (!same_magic(modmagic, vermagic, versindex)) {
2231 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2232 mod->name, modmagic, vermagic);
2233 err = -ENOEXEC;
2234 goto free_hdr;
2235 }
2236
2237 staging = get_modinfo(sechdrs, infoindex, "staging");
2238 if (staging) {
2239 add_taint_module(mod, TAINT_CRAP);
2240 printk(KERN_WARNING "%s: module is from the staging directory,"
2241 " the quality is unknown, you have been warned.\n",
2242 mod->name);
2243 }
2244
2245 /* Now copy in args */
2246 args = strndup_user(uargs, ~0UL >> 1);
2247 if (IS_ERR(args)) {
2248 err = PTR_ERR(args);
2249 goto free_hdr;
2250 }
2251
2252 strmap = kzalloc(BITS_TO_LONGS(sechdrs[strindex].sh_size)
2253 * sizeof(long), GFP_KERNEL);
2254 if (!strmap) {
2255 err = -ENOMEM;
2256 goto free_mod;
2257 }
2258
2259 mod->state = MODULE_STATE_COMING;
2260
2261 /* Allow arches to frob section contents and sizes. */
2262 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
2263 if (err < 0)
2264 goto free_mod;
2265
2266 if (pcpuindex) {
2267 /* We have a special allocation for this section. */
2268 err = percpu_modalloc(mod, sechdrs[pcpuindex].sh_size,
2269 sechdrs[pcpuindex].sh_addralign);
2270 if (err)
2271 goto free_mod;
2272 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2273 }
2274 /* Keep this around for failure path. */
2275 percpu = mod_percpu(mod);
2276
2277 /* Determine total sizes, and put offsets in sh_entsize. For now
2278 this is done generically; there doesn't appear to be any
2279 special cases for the architectures. */
2280 layout_sections(mod, hdr, sechdrs, secstrings);
2281 symoffs = layout_symtab(mod, sechdrs, symindex, strindex, hdr,
2282 secstrings, &stroffs, strmap);
2283
2284 /* Do the allocs. */
2285 ptr = module_alloc_update_bounds(mod->core_size);
2286 /*
2287 * The pointer to this block is stored in the module structure
2288 * which is inside the block. Just mark it as not being a
2289 * leak.
2290 */
2291 kmemleak_not_leak(ptr);
2292 if (!ptr) {
2293 err = -ENOMEM;
2294 goto free_percpu;
2295 }
2296 memset(ptr, 0, mod->core_size);
2297 mod->module_core = ptr;
2298
2299 ptr = module_alloc_update_bounds(mod->init_size);
2300 /*
2301 * The pointer to this block is stored in the module structure
2302 * which is inside the block. This block doesn't need to be
2303 * scanned as it contains data and code that will be freed
2304 * after the module is initialized.
2305 */
2306 kmemleak_ignore(ptr);
2307 if (!ptr && mod->init_size) {
2308 err = -ENOMEM;
2309 goto free_core;
2310 }
2311 memset(ptr, 0, mod->init_size);
2312 mod->module_init = ptr;
2313
2314 /* Transfer each section which specifies SHF_ALLOC */
2315 DEBUGP("final section addresses:\n");
2316 for (i = 0; i < hdr->e_shnum; i++) {
2317 void *dest;
2318
2319 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2320 continue;
2321
2322 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2323 dest = mod->module_init
2324 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2325 else
2326 dest = mod->module_core + sechdrs[i].sh_entsize;
2327
2328 if (sechdrs[i].sh_type != SHT_NOBITS)
2329 memcpy(dest, (void *)sechdrs[i].sh_addr,
2330 sechdrs[i].sh_size);
2331 /* Update sh_addr to point to copy in image. */
2332 sechdrs[i].sh_addr = (unsigned long)dest;
2333 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2334 }
2335 /* Module has been moved. */
2336 mod = (void *)sechdrs[modindex].sh_addr;
2337 kmemleak_load_module(mod, hdr, sechdrs, secstrings);
2338
2339#if defined(CONFIG_MODULE_UNLOAD)
2340 mod->refptr = alloc_percpu(struct module_ref);
2341 if (!mod->refptr) {
2342 err = -ENOMEM;
2343 goto free_init;
2344 }
2345#endif
2346 /* Now we've moved module, initialize linked lists, etc. */
2347 module_unload_init(mod);
2348
2349 /* Set up license info based on the info section */
2350 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2351
2352 /*
2353 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2354 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2355 * using GPL-only symbols it needs.
2356 */
2357 if (strcmp(mod->name, "ndiswrapper") == 0)
2358 add_taint(TAINT_PROPRIETARY_MODULE);
2359
2360 /* driverloader was caught wrongly pretending to be under GPL */
2361 if (strcmp(mod->name, "driverloader") == 0)
2362 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2363
2364 /* Set up MODINFO_ATTR fields */
2365 setup_modinfo(mod, sechdrs, infoindex);
2366
2367 /* Fix up syms, so that st_value is a pointer to location. */
2368 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2369 mod);
2370 if (err < 0)
2371 goto cleanup;
2372
2373 /* Now we've got everything in the final locations, we can
2374 * find optional sections. */
2375 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2376 sizeof(*mod->kp), &mod->num_kp);
2377 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2378 sizeof(*mod->syms), &mod->num_syms);
2379 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2380 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2381 sizeof(*mod->gpl_syms),
2382 &mod->num_gpl_syms);
2383 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2384 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2385 "__ksymtab_gpl_future",
2386 sizeof(*mod->gpl_future_syms),
2387 &mod->num_gpl_future_syms);
2388 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2389 "__kcrctab_gpl_future");
2390
2391#ifdef CONFIG_UNUSED_SYMBOLS
2392 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2393 "__ksymtab_unused",
2394 sizeof(*mod->unused_syms),
2395 &mod->num_unused_syms);
2396 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2397 "__kcrctab_unused");
2398 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2399 "__ksymtab_unused_gpl",
2400 sizeof(*mod->unused_gpl_syms),
2401 &mod->num_unused_gpl_syms);
2402 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2403 "__kcrctab_unused_gpl");
2404#endif
2405#ifdef CONFIG_CONSTRUCTORS
2406 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2407 sizeof(*mod->ctors), &mod->num_ctors);
2408#endif
2409
2410#ifdef CONFIG_TRACEPOINTS
2411 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2412 "__tracepoints",
2413 sizeof(*mod->tracepoints),
2414 &mod->num_tracepoints);
2415#endif
2416#ifdef CONFIG_EVENT_TRACING
2417 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2418 "_ftrace_events",
2419 sizeof(*mod->trace_events),
2420 &mod->num_trace_events);
2421 /*
2422 * This section contains pointers to allocated objects in the trace
2423 * code and not scanning it leads to false positives.
2424 */
2425 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2426 mod->num_trace_events, GFP_KERNEL);
2427#endif
2428#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2429 /* sechdrs[0].sh_size is always zero */
2430 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2431 "__mcount_loc",
2432 sizeof(*mod->ftrace_callsites),
2433 &mod->num_ftrace_callsites);
2434#endif
2435#ifdef CONFIG_MODVERSIONS
2436 if ((mod->num_syms && !mod->crcs)
2437 || (mod->num_gpl_syms && !mod->gpl_crcs)
2438 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2439#ifdef CONFIG_UNUSED_SYMBOLS
2440 || (mod->num_unused_syms && !mod->unused_crcs)
2441 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2442#endif
2443 ) {
2444 err = try_to_force_load(mod,
2445 "no versions for exported symbols");
2446 if (err)
2447 goto cleanup;
2448 }
2449#endif
2450
2451 /* Now do relocations. */
2452 for (i = 1; i < hdr->e_shnum; i++) {
2453 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2454 unsigned int info = sechdrs[i].sh_info;
2455
2456 /* Not a valid relocation section? */
2457 if (info >= hdr->e_shnum)
2458 continue;
2459
2460 /* Don't bother with non-allocated sections */
2461 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2462 continue;
2463
2464 if (sechdrs[i].sh_type == SHT_REL)
2465 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2466 else if (sechdrs[i].sh_type == SHT_RELA)
2467 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2468 mod);
2469 if (err < 0)
2470 goto cleanup;
2471 }
2472
2473 /* Set up and sort exception table */
2474 mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
2475 sizeof(*mod->extable), &mod->num_exentries);
2476 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2477
2478 /* Finally, copy percpu area over. */
2479 percpu_modcopy(mod, (void *)sechdrs[pcpuindex].sh_addr,
2480 sechdrs[pcpuindex].sh_size);
2481
2482 add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex,
2483 symoffs, stroffs, secstrings, strmap);
2484 kfree(strmap);
2485 strmap = NULL;
2486
2487 if (!mod->taints)
2488 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2489 sizeof(*debug), &num_debug);
2490
2491 err = module_finalize(hdr, sechdrs, mod);
2492 if (err < 0)
2493 goto cleanup;
2494
2495 /* flush the icache in correct context */
2496 old_fs = get_fs();
2497 set_fs(KERNEL_DS);
2498
2499 /*
2500 * Flush the instruction cache, since we've played with text.
2501 * Do it before processing of module parameters, so the module
2502 * can provide parameter accessor functions of its own.
2503 */
2504 if (mod->module_init)
2505 flush_icache_range((unsigned long)mod->module_init,
2506 (unsigned long)mod->module_init
2507 + mod->init_size);
2508 flush_icache_range((unsigned long)mod->module_core,
2509 (unsigned long)mod->module_core + mod->core_size);
2510
2511 set_fs(old_fs);
2512
2513 mod->args = args;
2514 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2515 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2516 mod->name);
2517
2518 /* Now sew it into the lists so we can get lockdep and oops
2519 * info during argument parsing. Noone should access us, since
2520 * strong_try_module_get() will fail.
2521 * lockdep/oops can run asynchronous, so use the RCU list insertion
2522 * function to insert in a way safe to concurrent readers.
2523 * The mutex protects against concurrent writers.
2524 */
2525 mutex_lock(&module_mutex);
2526 if (find_module(mod->name)) {
2527 err = -EEXIST;
2528 goto unlock;
2529 }
2530
2531 if (debug)
2532 dynamic_debug_setup(debug, num_debug);
2533
2534 /* Find duplicate symbols */
2535 err = verify_export_symbols(mod);
2536 if (err < 0)
2537 goto ddebug;
2538
2539 list_add_rcu(&mod->list, &modules);
2540 mutex_unlock(&module_mutex);
2541
2542 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2543 if (err < 0)
2544 goto unlink;
2545
2546 err = mod_sysfs_setup(mod, mod->kp, mod->num_kp);
2547 if (err < 0)
2548 goto unlink;
2549
2550 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2551 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2552
2553 /* Get rid of temporary copy */
2554 vfree(hdr);
2555
2556 trace_module_load(mod);
2557
2558 /* Done! */
2559 return mod;
2560
2561 unlink:
2562 mutex_lock(&module_mutex);
2563 /* Unlink carefully: kallsyms could be walking list. */
2564 list_del_rcu(&mod->list);
2565 ddebug:
2566 dynamic_debug_remove(debug);
2567 unlock:
2568 mutex_unlock(&module_mutex);
2569 synchronize_sched();
2570 module_arch_cleanup(mod);
2571 cleanup:
2572 free_modinfo(mod);
2573 module_unload_free(mod);
2574#if defined(CONFIG_MODULE_UNLOAD)
2575 free_percpu(mod->refptr);
2576 free_init:
2577#endif
2578 module_free(mod, mod->module_init);
2579 free_core:
2580 module_free(mod, mod->module_core);
2581 /* mod will be freed with core. Don't access it beyond this line! */
2582 free_percpu:
2583 free_percpu(percpu);
2584 free_mod:
2585 kfree(args);
2586 kfree(strmap);
2587 free_hdr:
2588 vfree(hdr);
2589 return ERR_PTR(err);
2590
2591 truncated:
2592 printk(KERN_ERR "Module len %lu truncated\n", len);
2593 err = -ENOEXEC;
2594 goto free_hdr;
2595}
2596
2597/* Call module constructors. */
2598static void do_mod_ctors(struct module *mod)
2599{
2600#ifdef CONFIG_CONSTRUCTORS
2601 unsigned long i;
2602
2603 for (i = 0; i < mod->num_ctors; i++)
2604 mod->ctors[i]();
2605#endif
2606}
2607
2608/* This is where the real work happens */
2609SYSCALL_DEFINE3(init_module, void __user *, umod,
2610 unsigned long, len, const char __user *, uargs)
2611{
2612 struct module *mod;
2613 int ret = 0;
2614
2615 /* Must have permission */
2616 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2617 return -EPERM;
2618
2619 /* Do all the hard work */
2620 mod = load_module(umod, len, uargs);
2621 if (IS_ERR(mod))
2622 return PTR_ERR(mod);
2623
2624 blocking_notifier_call_chain(&module_notify_list,
2625 MODULE_STATE_COMING, mod);
2626
2627 do_mod_ctors(mod);
2628 /* Start the module */
2629 if (mod->init != NULL)
2630 ret = do_one_initcall(mod->init);
2631 if (ret < 0) {
2632 /* Init routine failed: abort. Try to protect us from
2633 buggy refcounters. */
2634 mod->state = MODULE_STATE_GOING;
2635 synchronize_sched();
2636 module_put(mod);
2637 blocking_notifier_call_chain(&module_notify_list,
2638 MODULE_STATE_GOING, mod);
2639 free_module(mod);
2640 wake_up(&module_wq);
2641 return ret;
2642 }
2643 if (ret > 0) {
2644 printk(KERN_WARNING
2645"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2646"%s: loading module anyway...\n",
2647 __func__, mod->name, ret,
2648 __func__);
2649 dump_stack();
2650 }
2651
2652 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2653 mod->state = MODULE_STATE_LIVE;
2654 wake_up(&module_wq);
2655 blocking_notifier_call_chain(&module_notify_list,
2656 MODULE_STATE_LIVE, mod);
2657
2658 /* We need to finish all async code before the module init sequence is done */
2659 async_synchronize_full();
2660
2661 mutex_lock(&module_mutex);
2662 /* Drop initial reference. */
2663 module_put(mod);
2664 trim_init_extable(mod);
2665#ifdef CONFIG_KALLSYMS
2666 mod->num_symtab = mod->core_num_syms;
2667 mod->symtab = mod->core_symtab;
2668 mod->strtab = mod->core_strtab;
2669#endif
2670 module_free(mod, mod->module_init);
2671 mod->module_init = NULL;
2672 mod->init_size = 0;
2673 mod->init_text_size = 0;
2674 mutex_unlock(&module_mutex);
2675
2676 return 0;
2677}
2678
2679static inline int within(unsigned long addr, void *start, unsigned long size)
2680{
2681 return ((void *)addr >= start && (void *)addr < start + size);
2682}
2683
2684#ifdef CONFIG_KALLSYMS
2685/*
2686 * This ignores the intensely annoying "mapping symbols" found
2687 * in ARM ELF files: $a, $t and $d.
2688 */
2689static inline int is_arm_mapping_symbol(const char *str)
2690{
2691 return str[0] == '$' && strchr("atd", str[1])
2692 && (str[2] == '\0' || str[2] == '.');
2693}
2694
2695static const char *get_ksymbol(struct module *mod,
2696 unsigned long addr,
2697 unsigned long *size,
2698 unsigned long *offset)
2699{
2700 unsigned int i, best = 0;
2701 unsigned long nextval;
2702
2703 /* At worse, next value is at end of module */
2704 if (within_module_init(addr, mod))
2705 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2706 else
2707 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2708
2709 /* Scan for closest preceeding symbol, and next symbol. (ELF
2710 starts real symbols at 1). */
2711 for (i = 1; i < mod->num_symtab; i++) {
2712 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2713 continue;
2714
2715 /* We ignore unnamed symbols: they're uninformative
2716 * and inserted at a whim. */
2717 if (mod->symtab[i].st_value <= addr
2718 && mod->symtab[i].st_value > mod->symtab[best].st_value
2719 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2720 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2721 best = i;
2722 if (mod->symtab[i].st_value > addr
2723 && mod->symtab[i].st_value < nextval
2724 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2725 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2726 nextval = mod->symtab[i].st_value;
2727 }
2728
2729 if (!best)
2730 return NULL;
2731
2732 if (size)
2733 *size = nextval - mod->symtab[best].st_value;
2734 if (offset)
2735 *offset = addr - mod->symtab[best].st_value;
2736 return mod->strtab + mod->symtab[best].st_name;
2737}
2738
2739/* For kallsyms to ask for address resolution. NULL means not found. Careful
2740 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2741const char *module_address_lookup(unsigned long addr,
2742 unsigned long *size,
2743 unsigned long *offset,
2744 char **modname,
2745 char *namebuf)
2746{
2747 struct module *mod;
2748 const char *ret = NULL;
2749
2750 preempt_disable();
2751 list_for_each_entry_rcu(mod, &modules, list) {
2752 if (within_module_init(addr, mod) ||
2753 within_module_core(addr, mod)) {
2754 if (modname)
2755 *modname = mod->name;
2756 ret = get_ksymbol(mod, addr, size, offset);
2757 break;
2758 }
2759 }
2760 /* Make a copy in here where it's safe */
2761 if (ret) {
2762 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2763 ret = namebuf;
2764 }
2765 preempt_enable();
2766 return ret;
2767}
2768
2769int lookup_module_symbol_name(unsigned long addr, char *symname)
2770{
2771 struct module *mod;
2772
2773 preempt_disable();
2774 list_for_each_entry_rcu(mod, &modules, list) {
2775 if (within_module_init(addr, mod) ||
2776 within_module_core(addr, mod)) {
2777 const char *sym;
2778
2779 sym = get_ksymbol(mod, addr, NULL, NULL);
2780 if (!sym)
2781 goto out;
2782 strlcpy(symname, sym, KSYM_NAME_LEN);
2783 preempt_enable();
2784 return 0;
2785 }
2786 }
2787out:
2788 preempt_enable();
2789 return -ERANGE;
2790}
2791
2792int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2793 unsigned long *offset, char *modname, char *name)
2794{
2795 struct module *mod;
2796
2797 preempt_disable();
2798 list_for_each_entry_rcu(mod, &modules, list) {
2799 if (within_module_init(addr, mod) ||
2800 within_module_core(addr, mod)) {
2801 const char *sym;
2802
2803 sym = get_ksymbol(mod, addr, size, offset);
2804 if (!sym)
2805 goto out;
2806 if (modname)
2807 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2808 if (name)
2809 strlcpy(name, sym, KSYM_NAME_LEN);
2810 preempt_enable();
2811 return 0;
2812 }
2813 }
2814out:
2815 preempt_enable();
2816 return -ERANGE;
2817}
2818
2819int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2820 char *name, char *module_name, int *exported)
2821{
2822 struct module *mod;
2823
2824 preempt_disable();
2825 list_for_each_entry_rcu(mod, &modules, list) {
2826 if (symnum < mod->num_symtab) {
2827 *value = mod->symtab[symnum].st_value;
2828 *type = mod->symtab[symnum].st_info;
2829 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2830 KSYM_NAME_LEN);
2831 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2832 *exported = is_exported(name, *value, mod);
2833 preempt_enable();
2834 return 0;
2835 }
2836 symnum -= mod->num_symtab;
2837 }
2838 preempt_enable();
2839 return -ERANGE;
2840}
2841
2842static unsigned long mod_find_symname(struct module *mod, const char *name)
2843{
2844 unsigned int i;
2845
2846 for (i = 0; i < mod->num_symtab; i++)
2847 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2848 mod->symtab[i].st_info != 'U')
2849 return mod->symtab[i].st_value;
2850 return 0;
2851}
2852
2853/* Look for this name: can be of form module:name. */
2854unsigned long module_kallsyms_lookup_name(const char *name)
2855{
2856 struct module *mod;
2857 char *colon;
2858 unsigned long ret = 0;
2859
2860 /* Don't lock: we're in enough trouble already. */
2861 preempt_disable();
2862 if ((colon = strchr(name, ':')) != NULL) {
2863 *colon = '\0';
2864 if ((mod = find_module(name)) != NULL)
2865 ret = mod_find_symname(mod, colon+1);
2866 *colon = ':';
2867 } else {
2868 list_for_each_entry_rcu(mod, &modules, list)
2869 if ((ret = mod_find_symname(mod, name)) != 0)
2870 break;
2871 }
2872 preempt_enable();
2873 return ret;
2874}
2875
2876int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
2877 struct module *, unsigned long),
2878 void *data)
2879{
2880 struct module *mod;
2881 unsigned int i;
2882 int ret;
2883
2884 list_for_each_entry(mod, &modules, list) {
2885 for (i = 0; i < mod->num_symtab; i++) {
2886 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
2887 mod, mod->symtab[i].st_value);
2888 if (ret != 0)
2889 return ret;
2890 }
2891 }
2892 return 0;
2893}
2894#endif /* CONFIG_KALLSYMS */
2895
2896static char *module_flags(struct module *mod, char *buf)
2897{
2898 int bx = 0;
2899
2900 if (mod->taints ||
2901 mod->state == MODULE_STATE_GOING ||
2902 mod->state == MODULE_STATE_COMING) {
2903 buf[bx++] = '(';
2904 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2905 buf[bx++] = 'P';
2906 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2907 buf[bx++] = 'F';
2908 if (mod->taints & (1 << TAINT_CRAP))
2909 buf[bx++] = 'C';
2910 /*
2911 * TAINT_FORCED_RMMOD: could be added.
2912 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2913 * apply to modules.
2914 */
2915
2916 /* Show a - for module-is-being-unloaded */
2917 if (mod->state == MODULE_STATE_GOING)
2918 buf[bx++] = '-';
2919 /* Show a + for module-is-being-loaded */
2920 if (mod->state == MODULE_STATE_COMING)
2921 buf[bx++] = '+';
2922 buf[bx++] = ')';
2923 }
2924 buf[bx] = '\0';
2925
2926 return buf;
2927}
2928
2929#ifdef CONFIG_PROC_FS
2930/* Called by the /proc file system to return a list of modules. */
2931static void *m_start(struct seq_file *m, loff_t *pos)
2932{
2933 mutex_lock(&module_mutex);
2934 return seq_list_start(&modules, *pos);
2935}
2936
2937static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2938{
2939 return seq_list_next(p, &modules, pos);
2940}
2941
2942static void m_stop(struct seq_file *m, void *p)
2943{
2944 mutex_unlock(&module_mutex);
2945}
2946
2947static int m_show(struct seq_file *m, void *p)
2948{
2949 struct module *mod = list_entry(p, struct module, list);
2950 char buf[8];
2951
2952 seq_printf(m, "%s %u",
2953 mod->name, mod->init_size + mod->core_size);
2954 print_unload_info(m, mod);
2955
2956 /* Informative for users. */
2957 seq_printf(m, " %s",
2958 mod->state == MODULE_STATE_GOING ? "Unloading":
2959 mod->state == MODULE_STATE_COMING ? "Loading":
2960 "Live");
2961 /* Used by oprofile and other similar tools. */
2962 seq_printf(m, " 0x%p", mod->module_core);
2963
2964 /* Taints info */
2965 if (mod->taints)
2966 seq_printf(m, " %s", module_flags(mod, buf));
2967
2968 seq_printf(m, "\n");
2969 return 0;
2970}
2971
2972/* Format: modulename size refcount deps address
2973
2974 Where refcount is a number or -, and deps is a comma-separated list
2975 of depends or -.
2976*/
2977static const struct seq_operations modules_op = {
2978 .start = m_start,
2979 .next = m_next,
2980 .stop = m_stop,
2981 .show = m_show
2982};
2983
2984static int modules_open(struct inode *inode, struct file *file)
2985{
2986 return seq_open(file, &modules_op);
2987}
2988
2989static const struct file_operations proc_modules_operations = {
2990 .open = modules_open,
2991 .read = seq_read,
2992 .llseek = seq_lseek,
2993 .release = seq_release,
2994};
2995
2996static int __init proc_modules_init(void)
2997{
2998 proc_create("modules", 0, NULL, &proc_modules_operations);
2999 return 0;
3000}
3001module_init(proc_modules_init);
3002#endif
3003
3004/* Given an address, look for it in the module exception tables. */
3005const struct exception_table_entry *search_module_extables(unsigned long addr)
3006{
3007 const struct exception_table_entry *e = NULL;
3008 struct module *mod;
3009
3010 preempt_disable();
3011 list_for_each_entry_rcu(mod, &modules, list) {
3012 if (mod->num_exentries == 0)
3013 continue;
3014
3015 e = search_extable(mod->extable,
3016 mod->extable + mod->num_exentries - 1,
3017 addr);
3018 if (e)
3019 break;
3020 }
3021 preempt_enable();
3022
3023 /* Now, if we found one, we are running inside it now, hence
3024 we cannot unload the module, hence no refcnt needed. */
3025 return e;
3026}
3027
3028/*
3029 * is_module_address - is this address inside a module?
3030 * @addr: the address to check.
3031 *
3032 * See is_module_text_address() if you simply want to see if the address
3033 * is code (not data).
3034 */
3035bool is_module_address(unsigned long addr)
3036{
3037 bool ret;
3038
3039 preempt_disable();
3040 ret = __module_address(addr) != NULL;
3041 preempt_enable();
3042
3043 return ret;
3044}
3045
3046/*
3047 * __module_address - get the module which contains an address.
3048 * @addr: the address.
3049 *
3050 * Must be called with preempt disabled or module mutex held so that
3051 * module doesn't get freed during this.
3052 */
3053struct module *__module_address(unsigned long addr)
3054{
3055 struct module *mod;
3056
3057 if (addr < module_addr_min || addr > module_addr_max)
3058 return NULL;
3059
3060 list_for_each_entry_rcu(mod, &modules, list)
3061 if (within_module_core(addr, mod)
3062 || within_module_init(addr, mod))
3063 return mod;
3064 return NULL;
3065}
3066EXPORT_SYMBOL_GPL(__module_address);
3067
3068/*
3069 * is_module_text_address - is this address inside module code?
3070 * @addr: the address to check.
3071 *
3072 * See is_module_address() if you simply want to see if the address is
3073 * anywhere in a module. See kernel_text_address() for testing if an
3074 * address corresponds to kernel or module code.
3075 */
3076bool is_module_text_address(unsigned long addr)
3077{
3078 bool ret;
3079
3080 preempt_disable();
3081 ret = __module_text_address(addr) != NULL;
3082 preempt_enable();
3083
3084 return ret;
3085}
3086
3087/*
3088 * __module_text_address - get the module whose code contains an address.
3089 * @addr: the address.
3090 *
3091 * Must be called with preempt disabled or module mutex held so that
3092 * module doesn't get freed during this.
3093 */
3094struct module *__module_text_address(unsigned long addr)
3095{
3096 struct module *mod = __module_address(addr);
3097 if (mod) {
3098 /* Make sure it's within the text section. */
3099 if (!within(addr, mod->module_init, mod->init_text_size)
3100 && !within(addr, mod->module_core, mod->core_text_size))
3101 mod = NULL;
3102 }
3103 return mod;
3104}
3105EXPORT_SYMBOL_GPL(__module_text_address);
3106
3107/* Don't grab lock, we're oopsing. */
3108void print_modules(void)
3109{
3110 struct module *mod;
3111 char buf[8];
3112
3113 printk(KERN_DEFAULT "Modules linked in:");
3114 /* Most callers should already have preempt disabled, but make sure */
3115 preempt_disable();
3116 list_for_each_entry_rcu(mod, &modules, list)
3117 printk(" %s%s", mod->name, module_flags(mod, buf));
3118 preempt_enable();
3119 if (last_unloaded_module[0])
3120 printk(" [last unloaded: %s]", last_unloaded_module);
3121 printk("\n");
3122}
3123
3124#ifdef CONFIG_MODVERSIONS
3125/* Generate the signature for all relevant module structures here.
3126 * If these change, we don't want to try to parse the module. */
3127void module_layout(struct module *mod,
3128 struct modversion_info *ver,
3129 struct kernel_param *kp,
3130 struct kernel_symbol *ks,
3131 struct tracepoint *tp)
3132{
3133}
3134EXPORT_SYMBOL(module_layout);
3135#endif
3136
3137#ifdef CONFIG_TRACEPOINTS
3138void module_update_tracepoints(void)
3139{
3140 struct module *mod;
3141
3142 mutex_lock(&module_mutex);
3143 list_for_each_entry(mod, &modules, list)
3144 if (!mod->taints)
3145 tracepoint_update_probe_range(mod->tracepoints,
3146 mod->tracepoints + mod->num_tracepoints);
3147 mutex_unlock(&module_mutex);
3148}
3149
3150/*
3151 * Returns 0 if current not found.
3152 * Returns 1 if current found.
3153 */
3154int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3155{
3156 struct module *iter_mod;
3157 int found = 0;
3158
3159 mutex_lock(&module_mutex);
3160 list_for_each_entry(iter_mod, &modules, list) {
3161 if (!iter_mod->taints) {
3162 /*
3163 * Sorted module list
3164 */
3165 if (iter_mod < iter->module)
3166 continue;
3167 else if (iter_mod > iter->module)
3168 iter->tracepoint = NULL;
3169 found = tracepoint_get_iter_range(&iter->tracepoint,
3170 iter_mod->tracepoints,
3171 iter_mod->tracepoints
3172 + iter_mod->num_tracepoints);
3173 if (found) {
3174 iter->module = iter_mod;
3175 break;
3176 }
3177 }
3178 }
3179 mutex_unlock(&module_mutex);
3180 return found;
3181}
3182#endif