projects/linux·blob v3.9-rc6 · refs

3852 lines · 96.7 KiB

1/*
2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002, 2010 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/export.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/file.h>
25#include <linux/fs.h>
26#include <linux/sysfs.h>
27#include <linux/kernel.h>
28#include <linux/slab.h>
29#include <linux/vmalloc.h>
30#include <linux/elf.h>
31#include <linux/proc_fs.h>
32#include <linux/security.h>
33#include <linux/seq_file.h>
34#include <linux/syscalls.h>
35#include <linux/fcntl.h>
36#include <linux/rcupdate.h>
37#include <linux/capability.h>
38#include <linux/cpu.h>
39#include <linux/moduleparam.h>
40#include <linux/errno.h>
41#include <linux/err.h>
42#include <linux/vermagic.h>
43#include <linux/notifier.h>
44#include <linux/sched.h>
45#include <linux/stop_machine.h>
46#include <linux/device.h>
47#include <linux/string.h>
48#include <linux/mutex.h>
49#include <linux/rculist.h>
50#include <asm/uaccess.h>
51#include <asm/cacheflush.h>
52#include <asm/mmu_context.h>
53#include <linux/license.h>
54#include <asm/sections.h>
55#include <linux/tracepoint.h>
56#include <linux/ftrace.h>
57#include <linux/async.h>
58#include <linux/percpu.h>
59#include <linux/kmemleak.h>
60#include <linux/jump_label.h>
61#include <linux/pfn.h>
62#include <linux/bsearch.h>
63#include <linux/fips.h>
64#include <uapi/linux/module.h>
65#include "module-internal.h"
66
67#define CREATE_TRACE_POINTS
68#include <trace/events/module.h>
69
70#ifndef ARCH_SHF_SMALL
71#define ARCH_SHF_SMALL 0
72#endif
73
74/*
75 * Modules' sections will be aligned on page boundaries
76 * to ensure complete separation of code and data, but
77 * only when CONFIG_DEBUG_SET_MODULE_RONX=y
78 */
79#ifdef CONFIG_DEBUG_SET_MODULE_RONX
80# define debug_align(X) ALIGN(X, PAGE_SIZE)
81#else
82# define debug_align(X) (X)
83#endif
84
85/*
86 * Given BASE and SIZE this macro calculates the number of pages the
87 * memory regions occupies
88 */
89#define MOD_NUMBER_OF_PAGES(BASE, SIZE) (((SIZE) > 0) ? \
90 (PFN_DOWN((unsigned long)(BASE) + (SIZE) - 1) - \
91 PFN_DOWN((unsigned long)BASE) + 1) \
92 : (0UL))
93
94/* If this is set, the section belongs in the init part of the module */
95#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
96
97/*
98 * Mutex protects:
99 * 1) List of modules (also safely readable with preempt_disable),
100 * 2) module_use links,
101 * 3) module_addr_min/module_addr_max.
102 * (delete uses stop_machine/add uses RCU list operations). */
103DEFINE_MUTEX(module_mutex);
104EXPORT_SYMBOL_GPL(module_mutex);
105static LIST_HEAD(modules);
106#ifdef CONFIG_KGDB_KDB
107struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
108#endif /* CONFIG_KGDB_KDB */
109
110#ifdef CONFIG_MODULE_SIG
111#ifdef CONFIG_MODULE_SIG_FORCE
112static bool sig_enforce = true;
113#else
114static bool sig_enforce = false;
115
116static int param_set_bool_enable_only(const char *val,
117 const struct kernel_param *kp)
118{
119 int err;
120 bool test;
121 struct kernel_param dummy_kp = *kp;
122
123 dummy_kp.arg = &test;
124
125 err = param_set_bool(val, &dummy_kp);
126 if (err)
127 return err;
128
129 /* Don't let them unset it once it's set! */
130 if (!test && sig_enforce)
131 return -EROFS;
132
133 if (test)
134 sig_enforce = true;
135 return 0;
136}
137
138static const struct kernel_param_ops param_ops_bool_enable_only = {
139 .set = param_set_bool_enable_only,
140 .get = param_get_bool,
141};
142#define param_check_bool_enable_only param_check_bool
143
144module_param(sig_enforce, bool_enable_only, 0644);
145#endif /* !CONFIG_MODULE_SIG_FORCE */
146#endif /* CONFIG_MODULE_SIG */
147
148/* Block module loading/unloading? */
149int modules_disabled = 0;
150core_param(nomodule, modules_disabled, bint, 0);
151
152/* Waiting for a module to finish initializing? */
153static DECLARE_WAIT_QUEUE_HEAD(module_wq);
154
155static BLOCKING_NOTIFIER_HEAD(module_notify_list);
156
157/* Bounds of module allocation, for speeding __module_address.
158 * Protected by module_mutex. */
159static unsigned long module_addr_min = -1UL, module_addr_max = 0;
160
161int register_module_notifier(struct notifier_block * nb)
162{
163 return blocking_notifier_chain_register(&module_notify_list, nb);
164}
165EXPORT_SYMBOL(register_module_notifier);
166
167int unregister_module_notifier(struct notifier_block * nb)
168{
169 return blocking_notifier_chain_unregister(&module_notify_list, nb);
170}
171EXPORT_SYMBOL(unregister_module_notifier);
172
173struct load_info {
174 Elf_Ehdr *hdr;
175 unsigned long len;
176 Elf_Shdr *sechdrs;
177 char *secstrings, *strtab;
178 unsigned long symoffs, stroffs;
179 struct _ddebug *debug;
180 unsigned int num_debug;
181 bool sig_ok;
182 struct {
183 unsigned int sym, str, mod, vers, info, pcpu;
184 } index;
185};
186
187/* We require a truly strong try_module_get(): 0 means failure due to
188 ongoing or failed initialization etc. */
189static inline int strong_try_module_get(struct module *mod)
190{
191 BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
192 if (mod && mod->state == MODULE_STATE_COMING)
193 return -EBUSY;
194 if (try_module_get(mod))
195 return 0;
196 else
197 return -ENOENT;
198}
199
200static inline void add_taint_module(struct module *mod, unsigned flag,
201 enum lockdep_ok lockdep_ok)
202{
203 add_taint(flag, lockdep_ok);
204 mod->taints |= (1U << flag);
205}
206
207/*
208 * A thread that wants to hold a reference to a module only while it
209 * is running can call this to safely exit. nfsd and lockd use this.
210 */
211void __module_put_and_exit(struct module *mod, long code)
212{
213 module_put(mod);
214 do_exit(code);
215}
216EXPORT_SYMBOL(__module_put_and_exit);
217
218/* Find a module section: 0 means not found. */
219static unsigned int find_sec(const struct load_info *info, const char *name)
220{
221 unsigned int i;
222
223 for (i = 1; i < info->hdr->e_shnum; i++) {
224 Elf_Shdr *shdr = &info->sechdrs[i];
225 /* Alloc bit cleared means "ignore it." */
226 if ((shdr->sh_flags & SHF_ALLOC)
227 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
228 return i;
229 }
230 return 0;
231}
232
233/* Find a module section, or NULL. */
234static void *section_addr(const struct load_info *info, const char *name)
235{
236 /* Section 0 has sh_addr 0. */
237 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
238}
239
240/* Find a module section, or NULL. Fill in number of "objects" in section. */
241static void *section_objs(const struct load_info *info,
242 const char *name,
243 size_t object_size,
244 unsigned int *num)
245{
246 unsigned int sec = find_sec(info, name);
247
248 /* Section 0 has sh_addr 0 and sh_size 0. */
249 *num = info->sechdrs[sec].sh_size / object_size;
250 return (void *)info->sechdrs[sec].sh_addr;
251}
252
253/* Provided by the linker */
254extern const struct kernel_symbol __start___ksymtab[];
255extern const struct kernel_symbol __stop___ksymtab[];
256extern const struct kernel_symbol __start___ksymtab_gpl[];
257extern const struct kernel_symbol __stop___ksymtab_gpl[];
258extern const struct kernel_symbol __start___ksymtab_gpl_future[];
259extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
260extern const unsigned long __start___kcrctab[];
261extern const unsigned long __start___kcrctab_gpl[];
262extern const unsigned long __start___kcrctab_gpl_future[];
263#ifdef CONFIG_UNUSED_SYMBOLS
264extern const struct kernel_symbol __start___ksymtab_unused[];
265extern const struct kernel_symbol __stop___ksymtab_unused[];
266extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
267extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
268extern const unsigned long __start___kcrctab_unused[];
269extern const unsigned long __start___kcrctab_unused_gpl[];
270#endif
271
272#ifndef CONFIG_MODVERSIONS
273#define symversion(base, idx) NULL
274#else
275#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
276#endif
277
278static bool each_symbol_in_section(const struct symsearch *arr,
279 unsigned int arrsize,
280 struct module *owner,
281 bool (*fn)(const struct symsearch *syms,
282 struct module *owner,
283 void *data),
284 void *data)
285{
286 unsigned int j;
287
288 for (j = 0; j < arrsize; j++) {
289 if (fn(&arr[j], owner, data))
290 return true;
291 }
292
293 return false;
294}
295
296/* Returns true as soon as fn returns true, otherwise false. */
297bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
298 struct module *owner,
299 void *data),
300 void *data)
301{
302 struct module *mod;
303 static const struct symsearch arr[] = {
304 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
305 NOT_GPL_ONLY, false },
306 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
307 __start___kcrctab_gpl,
308 GPL_ONLY, false },
309 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
310 __start___kcrctab_gpl_future,
311 WILL_BE_GPL_ONLY, false },
312#ifdef CONFIG_UNUSED_SYMBOLS
313 { __start___ksymtab_unused, __stop___ksymtab_unused,
314 __start___kcrctab_unused,
315 NOT_GPL_ONLY, true },
316 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
317 __start___kcrctab_unused_gpl,
318 GPL_ONLY, true },
319#endif
320 };
321
322 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
323 return true;
324
325 list_for_each_entry_rcu(mod, &modules, list) {
326 struct symsearch arr[] = {
327 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
328 NOT_GPL_ONLY, false },
329 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
330 mod->gpl_crcs,
331 GPL_ONLY, false },
332 { mod->gpl_future_syms,
333 mod->gpl_future_syms + mod->num_gpl_future_syms,
334 mod->gpl_future_crcs,
335 WILL_BE_GPL_ONLY, false },
336#ifdef CONFIG_UNUSED_SYMBOLS
337 { mod->unused_syms,
338 mod->unused_syms + mod->num_unused_syms,
339 mod->unused_crcs,
340 NOT_GPL_ONLY, true },
341 { mod->unused_gpl_syms,
342 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
343 mod->unused_gpl_crcs,
344 GPL_ONLY, true },
345#endif
346 };
347
348 if (mod->state == MODULE_STATE_UNFORMED)
349 continue;
350
351 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
352 return true;
353 }
354 return false;
355}
356EXPORT_SYMBOL_GPL(each_symbol_section);
357
358struct find_symbol_arg {
359 /* Input */
360 const char *name;
361 bool gplok;
362 bool warn;
363
364 /* Output */
365 struct module *owner;
366 const unsigned long *crc;
367 const struct kernel_symbol *sym;
368};
369
370static bool check_symbol(const struct symsearch *syms,
371 struct module *owner,
372 unsigned int symnum, void *data)
373{
374 struct find_symbol_arg *fsa = data;
375
376 if (!fsa->gplok) {
377 if (syms->licence == GPL_ONLY)
378 return false;
379 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
380 printk(KERN_WARNING "Symbol %s is being used "
381 "by a non-GPL module, which will not "
382 "be allowed in the future\n", fsa->name);
383 }
384 }
385
386#ifdef CONFIG_UNUSED_SYMBOLS
387 if (syms->unused && fsa->warn) {
388 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
389 "however this module is using it.\n", fsa->name);
390 printk(KERN_WARNING
391 "This symbol will go away in the future.\n");
392 printk(KERN_WARNING
393 "Please evalute if this is the right api to use and if "
394 "it really is, submit a report the linux kernel "
395 "mailinglist together with submitting your code for "
396 "inclusion.\n");
397 }
398#endif
399
400 fsa->owner = owner;
401 fsa->crc = symversion(syms->crcs, symnum);
402 fsa->sym = &syms->start[symnum];
403 return true;
404}
405
406static int cmp_name(const void *va, const void *vb)
407{
408 const char *a;
409 const struct kernel_symbol *b;
410 a = va; b = vb;
411 return strcmp(a, b->name);
412}
413
414static bool find_symbol_in_section(const struct symsearch *syms,
415 struct module *owner,
416 void *data)
417{
418 struct find_symbol_arg *fsa = data;
419 struct kernel_symbol *sym;
420
421 sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
422 sizeof(struct kernel_symbol), cmp_name);
423
424 if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
425 return true;
426
427 return false;
428}
429
430/* Find a symbol and return it, along with, (optional) crc and
431 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
432const struct kernel_symbol *find_symbol(const char *name,
433 struct module **owner,
434 const unsigned long **crc,
435 bool gplok,
436 bool warn)
437{
438 struct find_symbol_arg fsa;
439
440 fsa.name = name;
441 fsa.gplok = gplok;
442 fsa.warn = warn;
443
444 if (each_symbol_section(find_symbol_in_section, &fsa)) {
445 if (owner)
446 *owner = fsa.owner;
447 if (crc)
448 *crc = fsa.crc;
449 return fsa.sym;
450 }
451
452 pr_debug("Failed to find symbol %s\n", name);
453 return NULL;
454}
455EXPORT_SYMBOL_GPL(find_symbol);
456
457/* Search for module by name: must hold module_mutex. */
458static struct module *find_module_all(const char *name,
459 bool even_unformed)
460{
461 struct module *mod;
462
463 list_for_each_entry(mod, &modules, list) {
464 if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
465 continue;
466 if (strcmp(mod->name, name) == 0)
467 return mod;
468 }
469 return NULL;
470}
471
472struct module *find_module(const char *name)
473{
474 return find_module_all(name, false);
475}
476EXPORT_SYMBOL_GPL(find_module);
477
478#ifdef CONFIG_SMP
479
480static inline void __percpu *mod_percpu(struct module *mod)
481{
482 return mod->percpu;
483}
484
485static int percpu_modalloc(struct module *mod,
486 unsigned long size, unsigned long align)
487{
488 if (align > PAGE_SIZE) {
489 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
490 mod->name, align, PAGE_SIZE);
491 align = PAGE_SIZE;
492 }
493
494 mod->percpu = __alloc_reserved_percpu(size, align);
495 if (!mod->percpu) {
496 printk(KERN_WARNING
497 "%s: Could not allocate %lu bytes percpu data\n",
498 mod->name, size);
499 return -ENOMEM;
500 }
501 mod->percpu_size = size;
502 return 0;
503}
504
505static void percpu_modfree(struct module *mod)
506{
507 free_percpu(mod->percpu);
508}
509
510static unsigned int find_pcpusec(struct load_info *info)
511{
512 return find_sec(info, ".data..percpu");
513}
514
515static void percpu_modcopy(struct module *mod,
516 const void *from, unsigned long size)
517{
518 int cpu;
519
520 for_each_possible_cpu(cpu)
521 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
522}
523
524/**
525 * is_module_percpu_address - test whether address is from module static percpu
526 * @addr: address to test
527 *
528 * Test whether @addr belongs to module static percpu area.
529 *
530 * RETURNS:
531 * %true if @addr is from module static percpu area
532 */
533bool is_module_percpu_address(unsigned long addr)
534{
535 struct module *mod;
536 unsigned int cpu;
537
538 preempt_disable();
539
540 list_for_each_entry_rcu(mod, &modules, list) {
541 if (mod->state == MODULE_STATE_UNFORMED)
542 continue;
543 if (!mod->percpu_size)
544 continue;
545 for_each_possible_cpu(cpu) {
546 void *start = per_cpu_ptr(mod->percpu, cpu);
547
548 if ((void *)addr >= start &&
549 (void *)addr < start + mod->percpu_size) {
550 preempt_enable();
551 return true;
552 }
553 }
554 }
555
556 preempt_enable();
557 return false;
558}
559
560#else /* ... !CONFIG_SMP */
561
562static inline void __percpu *mod_percpu(struct module *mod)
563{
564 return NULL;
565}
566static inline int percpu_modalloc(struct module *mod,
567 unsigned long size, unsigned long align)
568{
569 return -ENOMEM;
570}
571static inline void percpu_modfree(struct module *mod)
572{
573}
574static unsigned int find_pcpusec(struct load_info *info)
575{
576 return 0;
577}
578static inline void percpu_modcopy(struct module *mod,
579 const void *from, unsigned long size)
580{
581 /* pcpusec should be 0, and size of that section should be 0. */
582 BUG_ON(size != 0);
583}
584bool is_module_percpu_address(unsigned long addr)
585{
586 return false;
587}
588
589#endif /* CONFIG_SMP */
590
591#define MODINFO_ATTR(field) \
592static void setup_modinfo_##field(struct module *mod, const char *s) \
593{ \
594 mod->field = kstrdup(s, GFP_KERNEL); \
595} \
596static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
597 struct module_kobject *mk, char *buffer) \
598{ \
599 return sprintf(buffer, "%s\n", mk->mod->field); \
600} \
601static int modinfo_##field##_exists(struct module *mod) \
602{ \
603 return mod->field != NULL; \
604} \
605static void free_modinfo_##field(struct module *mod) \
606{ \
607 kfree(mod->field); \
608 mod->field = NULL; \
609} \
610static struct module_attribute modinfo_##field = { \
611 .attr = { .name = __stringify(field), .mode = 0444 }, \
612 .show = show_modinfo_##field, \
613 .setup = setup_modinfo_##field, \
614 .test = modinfo_##field##_exists, \
615 .free = free_modinfo_##field, \
616};
617
618MODINFO_ATTR(version);
619MODINFO_ATTR(srcversion);
620
621static char last_unloaded_module[MODULE_NAME_LEN+1];
622
623#ifdef CONFIG_MODULE_UNLOAD
624
625EXPORT_TRACEPOINT_SYMBOL(module_get);
626
627/* Init the unload section of the module. */
628static int module_unload_init(struct module *mod)
629{
630 mod->refptr = alloc_percpu(struct module_ref);
631 if (!mod->refptr)
632 return -ENOMEM;
633
634 INIT_LIST_HEAD(&mod->source_list);
635 INIT_LIST_HEAD(&mod->target_list);
636
637 /* Hold reference count during initialization. */
638 __this_cpu_write(mod->refptr->incs, 1);
639 /* Backwards compatibility macros put refcount during init. */
640 mod->waiter = current;
641
642 return 0;
643}
644
645/* Does a already use b? */
646static int already_uses(struct module *a, struct module *b)
647{
648 struct module_use *use;
649
650 list_for_each_entry(use, &b->source_list, source_list) {
651 if (use->source == a) {
652 pr_debug("%s uses %s!\n", a->name, b->name);
653 return 1;
654 }
655 }
656 pr_debug("%s does not use %s!\n", a->name, b->name);
657 return 0;
658}
659
660/*
661 * Module a uses b
662 * - we add 'a' as a "source", 'b' as a "target" of module use
663 * - the module_use is added to the list of 'b' sources (so
664 * 'b' can walk the list to see who sourced them), and of 'a'
665 * targets (so 'a' can see what modules it targets).
666 */
667static int add_module_usage(struct module *a, struct module *b)
668{
669 struct module_use *use;
670
671 pr_debug("Allocating new usage for %s.\n", a->name);
672 use = kmalloc(sizeof(*use), GFP_ATOMIC);
673 if (!use) {
674 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
675 return -ENOMEM;
676 }
677
678 use->source = a;
679 use->target = b;
680 list_add(&use->source_list, &b->source_list);
681 list_add(&use->target_list, &a->target_list);
682 return 0;
683}
684
685/* Module a uses b: caller needs module_mutex() */
686int ref_module(struct module *a, struct module *b)
687{
688 int err;
689
690 if (b == NULL || already_uses(a, b))
691 return 0;
692
693 /* If module isn't available, we fail. */
694 err = strong_try_module_get(b);
695 if (err)
696 return err;
697
698 err = add_module_usage(a, b);
699 if (err) {
700 module_put(b);
701 return err;
702 }
703 return 0;
704}
705EXPORT_SYMBOL_GPL(ref_module);
706
707/* Clear the unload stuff of the module. */
708static void module_unload_free(struct module *mod)
709{
710 struct module_use *use, *tmp;
711
712 mutex_lock(&module_mutex);
713 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
714 struct module *i = use->target;
715 pr_debug("%s unusing %s\n", mod->name, i->name);
716 module_put(i);
717 list_del(&use->source_list);
718 list_del(&use->target_list);
719 kfree(use);
720 }
721 mutex_unlock(&module_mutex);
722
723 free_percpu(mod->refptr);
724}
725
726#ifdef CONFIG_MODULE_FORCE_UNLOAD
727static inline int try_force_unload(unsigned int flags)
728{
729 int ret = (flags & O_TRUNC);
730 if (ret)
731 add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
732 return ret;
733}
734#else
735static inline int try_force_unload(unsigned int flags)
736{
737 return 0;
738}
739#endif /* CONFIG_MODULE_FORCE_UNLOAD */
740
741struct stopref
742{
743 struct module *mod;
744 int flags;
745 int *forced;
746};
747
748/* Whole machine is stopped with interrupts off when this runs. */
749static int __try_stop_module(void *_sref)
750{
751 struct stopref *sref = _sref;
752
753 /* If it's not unused, quit unless we're forcing. */
754 if (module_refcount(sref->mod) != 0) {
755 if (!(*sref->forced = try_force_unload(sref->flags)))
756 return -EWOULDBLOCK;
757 }
758
759 /* Mark it as dying. */
760 sref->mod->state = MODULE_STATE_GOING;
761 return 0;
762}
763
764static int try_stop_module(struct module *mod, int flags, int *forced)
765{
766 if (flags & O_NONBLOCK) {
767 struct stopref sref = { mod, flags, forced };
768
769 return stop_machine(__try_stop_module, &sref, NULL);
770 } else {
771 /* We don't need to stop the machine for this. */
772 mod->state = MODULE_STATE_GOING;
773 synchronize_sched();
774 return 0;
775 }
776}
777
778unsigned long module_refcount(struct module *mod)
779{
780 unsigned long incs = 0, decs = 0;
781 int cpu;
782
783 for_each_possible_cpu(cpu)
784 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
785 /*
786 * ensure the incs are added up after the decs.
787 * module_put ensures incs are visible before decs with smp_wmb.
788 *
789 * This 2-count scheme avoids the situation where the refcount
790 * for CPU0 is read, then CPU0 increments the module refcount,
791 * then CPU1 drops that refcount, then the refcount for CPU1 is
792 * read. We would record a decrement but not its corresponding
793 * increment so we would see a low count (disaster).
794 *
795 * Rare situation? But module_refcount can be preempted, and we
796 * might be tallying up 4096+ CPUs. So it is not impossible.
797 */
798 smp_rmb();
799 for_each_possible_cpu(cpu)
800 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
801 return incs - decs;
802}
803EXPORT_SYMBOL(module_refcount);
804
805/* This exists whether we can unload or not */
806static void free_module(struct module *mod);
807
808static void wait_for_zero_refcount(struct module *mod)
809{
810 /* Since we might sleep for some time, release the mutex first */
811 mutex_unlock(&module_mutex);
812 for (;;) {
813 pr_debug("Looking at refcount...\n");
814 set_current_state(TASK_UNINTERRUPTIBLE);
815 if (module_refcount(mod) == 0)
816 break;
817 schedule();
818 }
819 current->state = TASK_RUNNING;
820 mutex_lock(&module_mutex);
821}
822
823SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
824 unsigned int, flags)
825{
826 struct module *mod;
827 char name[MODULE_NAME_LEN];
828 int ret, forced = 0;
829
830 if (!capable(CAP_SYS_MODULE) || modules_disabled)
831 return -EPERM;
832
833 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
834 return -EFAULT;
835 name[MODULE_NAME_LEN-1] = '\0';
836
837 if (mutex_lock_interruptible(&module_mutex) != 0)
838 return -EINTR;
839
840 mod = find_module(name);
841 if (!mod) {
842 ret = -ENOENT;
843 goto out;
844 }
845
846 if (!list_empty(&mod->source_list)) {
847 /* Other modules depend on us: get rid of them first. */
848 ret = -EWOULDBLOCK;
849 goto out;
850 }
851
852 /* Doing init or already dying? */
853 if (mod->state != MODULE_STATE_LIVE) {
854 /* FIXME: if (force), slam module count and wake up
855 waiter --RR */
856 pr_debug("%s already dying\n", mod->name);
857 ret = -EBUSY;
858 goto out;
859 }
860
861 /* If it has an init func, it must have an exit func to unload */
862 if (mod->init && !mod->exit) {
863 forced = try_force_unload(flags);
864 if (!forced) {
865 /* This module can't be removed */
866 ret = -EBUSY;
867 goto out;
868 }
869 }
870
871 /* Set this up before setting mod->state */
872 mod->waiter = current;
873
874 /* Stop the machine so refcounts can't move and disable module. */
875 ret = try_stop_module(mod, flags, &forced);
876 if (ret != 0)
877 goto out;
878
879 /* Never wait if forced. */
880 if (!forced && module_refcount(mod) != 0)
881 wait_for_zero_refcount(mod);
882
883 mutex_unlock(&module_mutex);
884 /* Final destruction now no one is using it. */
885 if (mod->exit != NULL)
886 mod->exit();
887 blocking_notifier_call_chain(&module_notify_list,
888 MODULE_STATE_GOING, mod);
889 async_synchronize_full();
890
891 /* Store the name of the last unloaded module for diagnostic purposes */
892 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
893
894 free_module(mod);
895 return 0;
896out:
897 mutex_unlock(&module_mutex);
898 return ret;
899}
900
901static inline void print_unload_info(struct seq_file *m, struct module *mod)
902{
903 struct module_use *use;
904 int printed_something = 0;
905
906 seq_printf(m, " %lu ", module_refcount(mod));
907
908 /* Always include a trailing , so userspace can differentiate
909 between this and the old multi-field proc format. */
910 list_for_each_entry(use, &mod->source_list, source_list) {
911 printed_something = 1;
912 seq_printf(m, "%s,", use->source->name);
913 }
914
915 if (mod->init != NULL && mod->exit == NULL) {
916 printed_something = 1;
917 seq_printf(m, "[permanent],");
918 }
919
920 if (!printed_something)
921 seq_printf(m, "-");
922}
923
924void __symbol_put(const char *symbol)
925{
926 struct module *owner;
927
928 preempt_disable();
929 if (!find_symbol(symbol, &owner, NULL, true, false))
930 BUG();
931 module_put(owner);
932 preempt_enable();
933}
934EXPORT_SYMBOL(__symbol_put);
935
936/* Note this assumes addr is a function, which it currently always is. */
937void symbol_put_addr(void *addr)
938{
939 struct module *modaddr;
940 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
941
942 if (core_kernel_text(a))
943 return;
944
945 /* module_text_address is safe here: we're supposed to have reference
946 * to module from symbol_get, so it can't go away. */
947 modaddr = __module_text_address(a);
948 BUG_ON(!modaddr);
949 module_put(modaddr);
950}
951EXPORT_SYMBOL_GPL(symbol_put_addr);
952
953static ssize_t show_refcnt(struct module_attribute *mattr,
954 struct module_kobject *mk, char *buffer)
955{
956 return sprintf(buffer, "%lu\n", module_refcount(mk->mod));
957}
958
959static struct module_attribute modinfo_refcnt =
960 __ATTR(refcnt, 0444, show_refcnt, NULL);
961
962void __module_get(struct module *module)
963{
964 if (module) {
965 preempt_disable();
966 __this_cpu_inc(module->refptr->incs);
967 trace_module_get(module, _RET_IP_);
968 preempt_enable();
969 }
970}
971EXPORT_SYMBOL(__module_get);
972
973bool try_module_get(struct module *module)
974{
975 bool ret = true;
976
977 if (module) {
978 preempt_disable();
979
980 if (likely(module_is_live(module))) {
981 __this_cpu_inc(module->refptr->incs);
982 trace_module_get(module, _RET_IP_);
983 } else
984 ret = false;
985
986 preempt_enable();
987 }
988 return ret;
989}
990EXPORT_SYMBOL(try_module_get);
991
992void module_put(struct module *module)
993{
994 if (module) {
995 preempt_disable();
996 smp_wmb(); /* see comment in module_refcount */
997 __this_cpu_inc(module->refptr->decs);
998
999 trace_module_put(module, _RET_IP_);
1000 /* Maybe they're waiting for us to drop reference? */
1001 if (unlikely(!module_is_live(module)))
1002 wake_up_process(module->waiter);
1003 preempt_enable();
1004 }
1005}
1006EXPORT_SYMBOL(module_put);
1007
1008#else /* !CONFIG_MODULE_UNLOAD */
1009static inline void print_unload_info(struct seq_file *m, struct module *mod)
1010{
1011 /* We don't know the usage count, or what modules are using. */
1012 seq_printf(m, " - -");
1013}
1014
1015static inline void module_unload_free(struct module *mod)
1016{
1017}
1018
1019int ref_module(struct module *a, struct module *b)
1020{
1021 return strong_try_module_get(b);
1022}
1023EXPORT_SYMBOL_GPL(ref_module);
1024
1025static inline int module_unload_init(struct module *mod)
1026{
1027 return 0;
1028}
1029#endif /* CONFIG_MODULE_UNLOAD */
1030
1031static size_t module_flags_taint(struct module *mod, char *buf)
1032{
1033 size_t l = 0;
1034
1035 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
1036 buf[l++] = 'P';
1037 if (mod->taints & (1 << TAINT_OOT_MODULE))
1038 buf[l++] = 'O';
1039 if (mod->taints & (1 << TAINT_FORCED_MODULE))
1040 buf[l++] = 'F';
1041 if (mod->taints & (1 << TAINT_CRAP))
1042 buf[l++] = 'C';
1043 /*
1044 * TAINT_FORCED_RMMOD: could be added.
1045 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
1046 * apply to modules.
1047 */
1048 return l;
1049}
1050
1051static ssize_t show_initstate(struct module_attribute *mattr,
1052 struct module_kobject *mk, char *buffer)
1053{
1054 const char *state = "unknown";
1055
1056 switch (mk->mod->state) {
1057 case MODULE_STATE_LIVE:
1058 state = "live";
1059 break;
1060 case MODULE_STATE_COMING:
1061 state = "coming";
1062 break;
1063 case MODULE_STATE_GOING:
1064 state = "going";
1065 break;
1066 default:
1067 BUG();
1068 }
1069 return sprintf(buffer, "%s\n", state);
1070}
1071
1072static struct module_attribute modinfo_initstate =
1073 __ATTR(initstate, 0444, show_initstate, NULL);
1074
1075static ssize_t store_uevent(struct module_attribute *mattr,
1076 struct module_kobject *mk,
1077 const char *buffer, size_t count)
1078{
1079 enum kobject_action action;
1080
1081 if (kobject_action_type(buffer, count, &action) == 0)
1082 kobject_uevent(&mk->kobj, action);
1083 return count;
1084}
1085
1086struct module_attribute module_uevent =
1087 __ATTR(uevent, 0200, NULL, store_uevent);
1088
1089static ssize_t show_coresize(struct module_attribute *mattr,
1090 struct module_kobject *mk, char *buffer)
1091{
1092 return sprintf(buffer, "%u\n", mk->mod->core_size);
1093}
1094
1095static struct module_attribute modinfo_coresize =
1096 __ATTR(coresize, 0444, show_coresize, NULL);
1097
1098static ssize_t show_initsize(struct module_attribute *mattr,
1099 struct module_kobject *mk, char *buffer)
1100{
1101 return sprintf(buffer, "%u\n", mk->mod->init_size);
1102}
1103
1104static struct module_attribute modinfo_initsize =
1105 __ATTR(initsize, 0444, show_initsize, NULL);
1106
1107static ssize_t show_taint(struct module_attribute *mattr,
1108 struct module_kobject *mk, char *buffer)
1109{
1110 size_t l;
1111
1112 l = module_flags_taint(mk->mod, buffer);
1113 buffer[l++] = '\n';
1114 return l;
1115}
1116
1117static struct module_attribute modinfo_taint =
1118 __ATTR(taint, 0444, show_taint, NULL);
1119
1120static struct module_attribute *modinfo_attrs[] = {
1121 &module_uevent,
1122 &modinfo_version,
1123 &modinfo_srcversion,
1124 &modinfo_initstate,
1125 &modinfo_coresize,
1126 &modinfo_initsize,
1127 &modinfo_taint,
1128#ifdef CONFIG_MODULE_UNLOAD
1129 &modinfo_refcnt,
1130#endif
1131 NULL,
1132};
1133
1134static const char vermagic[] = VERMAGIC_STRING;
1135
1136static int try_to_force_load(struct module *mod, const char *reason)
1137{
1138#ifdef CONFIG_MODULE_FORCE_LOAD
1139 if (!test_taint(TAINT_FORCED_MODULE))
1140 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
1141 mod->name, reason);
1142 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
1143 return 0;
1144#else
1145 return -ENOEXEC;
1146#endif
1147}
1148
1149#ifdef CONFIG_MODVERSIONS
1150/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
1151static unsigned long maybe_relocated(unsigned long crc,
1152 const struct module *crc_owner)
1153{
1154#ifdef ARCH_RELOCATES_KCRCTAB
1155 if (crc_owner == NULL)
1156 return crc - (unsigned long)reloc_start;
1157#endif
1158 return crc;
1159}
1160
1161static int check_version(Elf_Shdr *sechdrs,
1162 unsigned int versindex,
1163 const char *symname,
1164 struct module *mod,
1165 const unsigned long *crc,
1166 const struct module *crc_owner)
1167{
1168 unsigned int i, num_versions;
1169 struct modversion_info *versions;
1170
1171 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1172 if (!crc)
1173 return 1;
1174
1175 /* No versions at all? modprobe --force does this. */
1176 if (versindex == 0)
1177 return try_to_force_load(mod, symname) == 0;
1178
1179 versions = (void *) sechdrs[versindex].sh_addr;
1180 num_versions = sechdrs[versindex].sh_size
1181 / sizeof(struct modversion_info);
1182
1183 for (i = 0; i < num_versions; i++) {
1184 if (strcmp(versions[i].name, symname) != 0)
1185 continue;
1186
1187 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
1188 return 1;
1189 pr_debug("Found checksum %lX vs module %lX\n",
1190 maybe_relocated(*crc, crc_owner), versions[i].crc);
1191 goto bad_version;
1192 }
1193
1194 printk(KERN_WARNING "%s: no symbol version for %s\n",
1195 mod->name, symname);
1196 return 0;
1197
1198bad_version:
1199 printk("%s: disagrees about version of symbol %s\n",
1200 mod->name, symname);
1201 return 0;
1202}
1203
1204static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1205 unsigned int versindex,
1206 struct module *mod)
1207{
1208 const unsigned long *crc;
1209
1210 /* Since this should be found in kernel (which can't be removed),
1211 * no locking is necessary. */
1212 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1213 &crc, true, false))
1214 BUG();
1215 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1216 NULL);
1217}
1218
1219/* First part is kernel version, which we ignore if module has crcs. */
1220static inline int same_magic(const char *amagic, const char *bmagic,
1221 bool has_crcs)
1222{
1223 if (has_crcs) {
1224 amagic += strcspn(amagic, " ");
1225 bmagic += strcspn(bmagic, " ");
1226 }
1227 return strcmp(amagic, bmagic) == 0;
1228}
1229#else
1230static inline int check_version(Elf_Shdr *sechdrs,
1231 unsigned int versindex,
1232 const char *symname,
1233 struct module *mod,
1234 const unsigned long *crc,
1235 const struct module *crc_owner)
1236{
1237 return 1;
1238}
1239
1240static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1241 unsigned int versindex,
1242 struct module *mod)
1243{
1244 return 1;
1245}
1246
1247static inline int same_magic(const char *amagic, const char *bmagic,
1248 bool has_crcs)
1249{
1250 return strcmp(amagic, bmagic) == 0;
1251}
1252#endif /* CONFIG_MODVERSIONS */
1253
1254/* Resolve a symbol for this module. I.e. if we find one, record usage. */
1255static const struct kernel_symbol *resolve_symbol(struct module *mod,
1256 const struct load_info *info,
1257 const char *name,
1258 char ownername[])
1259{
1260 struct module *owner;
1261 const struct kernel_symbol *sym;
1262 const unsigned long *crc;
1263 int err;
1264
1265 mutex_lock(&module_mutex);
1266 sym = find_symbol(name, &owner, &crc,
1267 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1268 if (!sym)
1269 goto unlock;
1270
1271 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1272 owner)) {
1273 sym = ERR_PTR(-EINVAL);
1274 goto getname;
1275 }
1276
1277 err = ref_module(mod, owner);
1278 if (err) {
1279 sym = ERR_PTR(err);
1280 goto getname;
1281 }
1282
1283getname:
1284 /* We must make copy under the lock if we failed to get ref. */
1285 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1286unlock:
1287 mutex_unlock(&module_mutex);
1288 return sym;
1289}
1290
1291static const struct kernel_symbol *
1292resolve_symbol_wait(struct module *mod,
1293 const struct load_info *info,
1294 const char *name)
1295{
1296 const struct kernel_symbol *ksym;
1297 char owner[MODULE_NAME_LEN];
1298
1299 if (wait_event_interruptible_timeout(module_wq,
1300 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1301 || PTR_ERR(ksym) != -EBUSY,
1302 30 * HZ) <= 0) {
1303 printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
1304 mod->name, owner);
1305 }
1306 return ksym;
1307}
1308
1309/*
1310 * /sys/module/foo/sections stuff
1311 * J. Corbet <[email protected]>
1312 */
1313#ifdef CONFIG_SYSFS
1314
1315#ifdef CONFIG_KALLSYMS
1316static inline bool sect_empty(const Elf_Shdr *sect)
1317{
1318 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1319}
1320
1321struct module_sect_attr
1322{
1323 struct module_attribute mattr;
1324 char *name;
1325 unsigned long address;
1326};
1327
1328struct module_sect_attrs
1329{
1330 struct attribute_group grp;
1331 unsigned int nsections;
1332 struct module_sect_attr attrs[0];
1333};
1334
1335static ssize_t module_sect_show(struct module_attribute *mattr,
1336 struct module_kobject *mk, char *buf)
1337{
1338 struct module_sect_attr *sattr =
1339 container_of(mattr, struct module_sect_attr, mattr);
1340 return sprintf(buf, "0x%pK\n", (void *)sattr->address);
1341}
1342
1343static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1344{
1345 unsigned int section;
1346
1347 for (section = 0; section < sect_attrs->nsections; section++)
1348 kfree(sect_attrs->attrs[section].name);
1349 kfree(sect_attrs);
1350}
1351
1352static void add_sect_attrs(struct module *mod, const struct load_info *info)
1353{
1354 unsigned int nloaded = 0, i, size[2];
1355 struct module_sect_attrs *sect_attrs;
1356 struct module_sect_attr *sattr;
1357 struct attribute **gattr;
1358
1359 /* Count loaded sections and allocate structures */
1360 for (i = 0; i < info->hdr->e_shnum; i++)
1361 if (!sect_empty(&info->sechdrs[i]))
1362 nloaded++;
1363 size[0] = ALIGN(sizeof(*sect_attrs)
1364 + nloaded * sizeof(sect_attrs->attrs[0]),
1365 sizeof(sect_attrs->grp.attrs[0]));
1366 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1367 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1368 if (sect_attrs == NULL)
1369 return;
1370
1371 /* Setup section attributes. */
1372 sect_attrs->grp.name = "sections";
1373 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1374
1375 sect_attrs->nsections = 0;
1376 sattr = &sect_attrs->attrs[0];
1377 gattr = &sect_attrs->grp.attrs[0];
1378 for (i = 0; i < info->hdr->e_shnum; i++) {
1379 Elf_Shdr *sec = &info->sechdrs[i];
1380 if (sect_empty(sec))
1381 continue;
1382 sattr->address = sec->sh_addr;
1383 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1384 GFP_KERNEL);
1385 if (sattr->name == NULL)
1386 goto out;
1387 sect_attrs->nsections++;
1388 sysfs_attr_init(&sattr->mattr.attr);
1389 sattr->mattr.show = module_sect_show;
1390 sattr->mattr.store = NULL;
1391 sattr->mattr.attr.name = sattr->name;
1392 sattr->mattr.attr.mode = S_IRUGO;
1393 *(gattr++) = &(sattr++)->mattr.attr;
1394 }
1395 *gattr = NULL;
1396
1397 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1398 goto out;
1399
1400 mod->sect_attrs = sect_attrs;
1401 return;
1402 out:
1403 free_sect_attrs(sect_attrs);
1404}
1405
1406static void remove_sect_attrs(struct module *mod)
1407{
1408 if (mod->sect_attrs) {
1409 sysfs_remove_group(&mod->mkobj.kobj,
1410 &mod->sect_attrs->grp);
1411 /* We are positive that no one is using any sect attrs
1412 * at this point. Deallocate immediately. */
1413 free_sect_attrs(mod->sect_attrs);
1414 mod->sect_attrs = NULL;
1415 }
1416}
1417
1418/*
1419 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1420 */
1421
1422struct module_notes_attrs {
1423 struct kobject *dir;
1424 unsigned int notes;
1425 struct bin_attribute attrs[0];
1426};
1427
1428static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1429 struct bin_attribute *bin_attr,
1430 char *buf, loff_t pos, size_t count)
1431{
1432 /*
1433 * The caller checked the pos and count against our size.
1434 */
1435 memcpy(buf, bin_attr->private + pos, count);
1436 return count;
1437}
1438
1439static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1440 unsigned int i)
1441{
1442 if (notes_attrs->dir) {
1443 while (i-- > 0)
1444 sysfs_remove_bin_file(notes_attrs->dir,
1445 &notes_attrs->attrs[i]);
1446 kobject_put(notes_attrs->dir);
1447 }
1448 kfree(notes_attrs);
1449}
1450
1451static void add_notes_attrs(struct module *mod, const struct load_info *info)
1452{
1453 unsigned int notes, loaded, i;
1454 struct module_notes_attrs *notes_attrs;
1455 struct bin_attribute *nattr;
1456
1457 /* failed to create section attributes, so can't create notes */
1458 if (!mod->sect_attrs)
1459 return;
1460
1461 /* Count notes sections and allocate structures. */
1462 notes = 0;
1463 for (i = 0; i < info->hdr->e_shnum; i++)
1464 if (!sect_empty(&info->sechdrs[i]) &&
1465 (info->sechdrs[i].sh_type == SHT_NOTE))
1466 ++notes;
1467
1468 if (notes == 0)
1469 return;
1470
1471 notes_attrs = kzalloc(sizeof(*notes_attrs)
1472 + notes * sizeof(notes_attrs->attrs[0]),
1473 GFP_KERNEL);
1474 if (notes_attrs == NULL)
1475 return;
1476
1477 notes_attrs->notes = notes;
1478 nattr = &notes_attrs->attrs[0];
1479 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1480 if (sect_empty(&info->sechdrs[i]))
1481 continue;
1482 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1483 sysfs_bin_attr_init(nattr);
1484 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1485 nattr->attr.mode = S_IRUGO;
1486 nattr->size = info->sechdrs[i].sh_size;
1487 nattr->private = (void *) info->sechdrs[i].sh_addr;
1488 nattr->read = module_notes_read;
1489 ++nattr;
1490 }
1491 ++loaded;
1492 }
1493
1494 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1495 if (!notes_attrs->dir)
1496 goto out;
1497
1498 for (i = 0; i < notes; ++i)
1499 if (sysfs_create_bin_file(notes_attrs->dir,
1500 &notes_attrs->attrs[i]))
1501 goto out;
1502
1503 mod->notes_attrs = notes_attrs;
1504 return;
1505
1506 out:
1507 free_notes_attrs(notes_attrs, i);
1508}
1509
1510static void remove_notes_attrs(struct module *mod)
1511{
1512 if (mod->notes_attrs)
1513 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1514}
1515
1516#else
1517
1518static inline void add_sect_attrs(struct module *mod,
1519 const struct load_info *info)
1520{
1521}
1522
1523static inline void remove_sect_attrs(struct module *mod)
1524{
1525}
1526
1527static inline void add_notes_attrs(struct module *mod,
1528 const struct load_info *info)
1529{
1530}
1531
1532static inline void remove_notes_attrs(struct module *mod)
1533{
1534}
1535#endif /* CONFIG_KALLSYMS */
1536
1537static void add_usage_links(struct module *mod)
1538{
1539#ifdef CONFIG_MODULE_UNLOAD
1540 struct module_use *use;
1541 int nowarn;
1542
1543 mutex_lock(&module_mutex);
1544 list_for_each_entry(use, &mod->target_list, target_list) {
1545 nowarn = sysfs_create_link(use->target->holders_dir,
1546 &mod->mkobj.kobj, mod->name);
1547 }
1548 mutex_unlock(&module_mutex);
1549#endif
1550}
1551
1552static void del_usage_links(struct module *mod)
1553{
1554#ifdef CONFIG_MODULE_UNLOAD
1555 struct module_use *use;
1556
1557 mutex_lock(&module_mutex);
1558 list_for_each_entry(use, &mod->target_list, target_list)
1559 sysfs_remove_link(use->target->holders_dir, mod->name);
1560 mutex_unlock(&module_mutex);
1561#endif
1562}
1563
1564static int module_add_modinfo_attrs(struct module *mod)
1565{
1566 struct module_attribute *attr;
1567 struct module_attribute *temp_attr;
1568 int error = 0;
1569 int i;
1570
1571 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1572 (ARRAY_SIZE(modinfo_attrs) + 1)),
1573 GFP_KERNEL);
1574 if (!mod->modinfo_attrs)
1575 return -ENOMEM;
1576
1577 temp_attr = mod->modinfo_attrs;
1578 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1579 if (!attr->test ||
1580 (attr->test && attr->test(mod))) {
1581 memcpy(temp_attr, attr, sizeof(*temp_attr));
1582 sysfs_attr_init(&temp_attr->attr);
1583 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1584 ++temp_attr;
1585 }
1586 }
1587 return error;
1588}
1589
1590static void module_remove_modinfo_attrs(struct module *mod)
1591{
1592 struct module_attribute *attr;
1593 int i;
1594
1595 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1596 /* pick a field to test for end of list */
1597 if (!attr->attr.name)
1598 break;
1599 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1600 if (attr->free)
1601 attr->free(mod);
1602 }
1603 kfree(mod->modinfo_attrs);
1604}
1605
1606static int mod_sysfs_init(struct module *mod)
1607{
1608 int err;
1609 struct kobject *kobj;
1610
1611 if (!module_sysfs_initialized) {
1612 printk(KERN_ERR "%s: module sysfs not initialized\n",
1613 mod->name);
1614 err = -EINVAL;
1615 goto out;
1616 }
1617
1618 kobj = kset_find_obj(module_kset, mod->name);
1619 if (kobj) {
1620 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1621 kobject_put(kobj);
1622 err = -EINVAL;
1623 goto out;
1624 }
1625
1626 mod->mkobj.mod = mod;
1627
1628 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1629 mod->mkobj.kobj.kset = module_kset;
1630 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1631 "%s", mod->name);
1632 if (err)
1633 kobject_put(&mod->mkobj.kobj);
1634
1635 /* delay uevent until full sysfs population */
1636out:
1637 return err;
1638}
1639
1640static int mod_sysfs_setup(struct module *mod,
1641 const struct load_info *info,
1642 struct kernel_param *kparam,
1643 unsigned int num_params)
1644{
1645 int err;
1646
1647 err = mod_sysfs_init(mod);
1648 if (err)
1649 goto out;
1650
1651 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1652 if (!mod->holders_dir) {
1653 err = -ENOMEM;
1654 goto out_unreg;
1655 }
1656
1657 err = module_param_sysfs_setup(mod, kparam, num_params);
1658 if (err)
1659 goto out_unreg_holders;
1660
1661 err = module_add_modinfo_attrs(mod);
1662 if (err)
1663 goto out_unreg_param;
1664
1665 add_usage_links(mod);
1666 add_sect_attrs(mod, info);
1667 add_notes_attrs(mod, info);
1668
1669 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1670 return 0;
1671
1672out_unreg_param:
1673 module_param_sysfs_remove(mod);
1674out_unreg_holders:
1675 kobject_put(mod->holders_dir);
1676out_unreg:
1677 kobject_put(&mod->mkobj.kobj);
1678out:
1679 return err;
1680}
1681
1682static void mod_sysfs_fini(struct module *mod)
1683{
1684 remove_notes_attrs(mod);
1685 remove_sect_attrs(mod);
1686 kobject_put(&mod->mkobj.kobj);
1687}
1688
1689#else /* !CONFIG_SYSFS */
1690
1691static int mod_sysfs_setup(struct module *mod,
1692 const struct load_info *info,
1693 struct kernel_param *kparam,
1694 unsigned int num_params)
1695{
1696 return 0;
1697}
1698
1699static void mod_sysfs_fini(struct module *mod)
1700{
1701}
1702
1703static void module_remove_modinfo_attrs(struct module *mod)
1704{
1705}
1706
1707static void del_usage_links(struct module *mod)
1708{
1709}
1710
1711#endif /* CONFIG_SYSFS */
1712
1713static void mod_sysfs_teardown(struct module *mod)
1714{
1715 del_usage_links(mod);
1716 module_remove_modinfo_attrs(mod);
1717 module_param_sysfs_remove(mod);
1718 kobject_put(mod->mkobj.drivers_dir);
1719 kobject_put(mod->holders_dir);
1720 mod_sysfs_fini(mod);
1721}
1722
1723/*
1724 * unlink the module with the whole machine is stopped with interrupts off
1725 * - this defends against kallsyms not taking locks
1726 */
1727static int __unlink_module(void *_mod)
1728{
1729 struct module *mod = _mod;
1730 list_del(&mod->list);
1731 module_bug_cleanup(mod);
1732 return 0;
1733}
1734
1735#ifdef CONFIG_DEBUG_SET_MODULE_RONX
1736/*
1737 * LKM RO/NX protection: protect module's text/ro-data
1738 * from modification and any data from execution.
1739 */
1740void set_page_attributes(void *start, void *end, int (*set)(unsigned long start, int num_pages))
1741{
1742 unsigned long begin_pfn = PFN_DOWN((unsigned long)start);
1743 unsigned long end_pfn = PFN_DOWN((unsigned long)end);
1744
1745 if (end_pfn > begin_pfn)
1746 set(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1747}
1748
1749static void set_section_ro_nx(void *base,
1750 unsigned long text_size,
1751 unsigned long ro_size,
1752 unsigned long total_size)
1753{
1754 /* begin and end PFNs of the current subsection */
1755 unsigned long begin_pfn;
1756 unsigned long end_pfn;
1757
1758 /*
1759 * Set RO for module text and RO-data:
1760 * - Always protect first page.
1761 * - Do not protect last partial page.
1762 */
1763 if (ro_size > 0)
1764 set_page_attributes(base, base + ro_size, set_memory_ro);
1765
1766 /*
1767 * Set NX permissions for module data:
1768 * - Do not protect first partial page.
1769 * - Always protect last page.
1770 */
1771 if (total_size > text_size) {
1772 begin_pfn = PFN_UP((unsigned long)base + text_size);
1773 end_pfn = PFN_UP((unsigned long)base + total_size);
1774 if (end_pfn > begin_pfn)
1775 set_memory_nx(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1776 }
1777}
1778
1779static void unset_module_core_ro_nx(struct module *mod)
1780{
1781 set_page_attributes(mod->module_core + mod->core_text_size,
1782 mod->module_core + mod->core_size,
1783 set_memory_x);
1784 set_page_attributes(mod->module_core,
1785 mod->module_core + mod->core_ro_size,
1786 set_memory_rw);
1787}
1788
1789static void unset_module_init_ro_nx(struct module *mod)
1790{
1791 set_page_attributes(mod->module_init + mod->init_text_size,
1792 mod->module_init + mod->init_size,
1793 set_memory_x);
1794 set_page_attributes(mod->module_init,
1795 mod->module_init + mod->init_ro_size,
1796 set_memory_rw);
1797}
1798
1799/* Iterate through all modules and set each module's text as RW */
1800void set_all_modules_text_rw(void)
1801{
1802 struct module *mod;
1803
1804 mutex_lock(&module_mutex);
1805 list_for_each_entry_rcu(mod, &modules, list) {
1806 if (mod->state == MODULE_STATE_UNFORMED)
1807 continue;
1808 if ((mod->module_core) && (mod->core_text_size)) {
1809 set_page_attributes(mod->module_core,
1810 mod->module_core + mod->core_text_size,
1811 set_memory_rw);
1812 }
1813 if ((mod->module_init) && (mod->init_text_size)) {
1814 set_page_attributes(mod->module_init,
1815 mod->module_init + mod->init_text_size,
1816 set_memory_rw);
1817 }
1818 }
1819 mutex_unlock(&module_mutex);
1820}
1821
1822/* Iterate through all modules and set each module's text as RO */
1823void set_all_modules_text_ro(void)
1824{
1825 struct module *mod;
1826
1827 mutex_lock(&module_mutex);
1828 list_for_each_entry_rcu(mod, &modules, list) {
1829 if (mod->state == MODULE_STATE_UNFORMED)
1830 continue;
1831 if ((mod->module_core) && (mod->core_text_size)) {
1832 set_page_attributes(mod->module_core,
1833 mod->module_core + mod->core_text_size,
1834 set_memory_ro);
1835 }
1836 if ((mod->module_init) && (mod->init_text_size)) {
1837 set_page_attributes(mod->module_init,
1838 mod->module_init + mod->init_text_size,
1839 set_memory_ro);
1840 }
1841 }
1842 mutex_unlock(&module_mutex);
1843}
1844#else
1845static inline void set_section_ro_nx(void *base, unsigned long text_size, unsigned long ro_size, unsigned long total_size) { }
1846static void unset_module_core_ro_nx(struct module *mod) { }
1847static void unset_module_init_ro_nx(struct module *mod) { }
1848#endif
1849
1850void __weak module_free(struct module *mod, void *module_region)
1851{
1852 vfree(module_region);
1853}
1854
1855void __weak module_arch_cleanup(struct module *mod)
1856{
1857}
1858
1859/* Free a module, remove from lists, etc. */
1860static void free_module(struct module *mod)
1861{
1862 trace_module_free(mod);
1863
1864 /* Delete from various lists */
1865 mutex_lock(&module_mutex);
1866 stop_machine(__unlink_module, mod, NULL);
1867 mutex_unlock(&module_mutex);
1868 mod_sysfs_teardown(mod);
1869
1870 /* Remove dynamic debug info */
1871 ddebug_remove_module(mod->name);
1872
1873 /* Arch-specific cleanup. */
1874 module_arch_cleanup(mod);
1875
1876 /* Module unload stuff */
1877 module_unload_free(mod);
1878
1879 /* Free any allocated parameters. */
1880 destroy_params(mod->kp, mod->num_kp);
1881
1882 /* This may be NULL, but that's OK */
1883 unset_module_init_ro_nx(mod);
1884 module_free(mod, mod->module_init);
1885 kfree(mod->args);
1886 percpu_modfree(mod);
1887
1888 /* Free lock-classes: */
1889 lockdep_free_key_range(mod->module_core, mod->core_size);
1890
1891 /* Finally, free the core (containing the module structure) */
1892 unset_module_core_ro_nx(mod);
1893 module_free(mod, mod->module_core);
1894
1895#ifdef CONFIG_MPU
1896 update_protections(current->mm);
1897#endif
1898}
1899
1900void *__symbol_get(const char *symbol)
1901{
1902 struct module *owner;
1903 const struct kernel_symbol *sym;
1904
1905 preempt_disable();
1906 sym = find_symbol(symbol, &owner, NULL, true, true);
1907 if (sym && strong_try_module_get(owner))
1908 sym = NULL;
1909 preempt_enable();
1910
1911 return sym ? (void *)sym->value : NULL;
1912}
1913EXPORT_SYMBOL_GPL(__symbol_get);
1914
1915/*
1916 * Ensure that an exported symbol [global namespace] does not already exist
1917 * in the kernel or in some other module's exported symbol table.
1918 *
1919 * You must hold the module_mutex.
1920 */
1921static int verify_export_symbols(struct module *mod)
1922{
1923 unsigned int i;
1924 struct module *owner;
1925 const struct kernel_symbol *s;
1926 struct {
1927 const struct kernel_symbol *sym;
1928 unsigned int num;
1929 } arr[] = {
1930 { mod->syms, mod->num_syms },
1931 { mod->gpl_syms, mod->num_gpl_syms },
1932 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1933#ifdef CONFIG_UNUSED_SYMBOLS
1934 { mod->unused_syms, mod->num_unused_syms },
1935 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1936#endif
1937 };
1938
1939 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1940 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1941 if (find_symbol(s->name, &owner, NULL, true, false)) {
1942 printk(KERN_ERR
1943 "%s: exports duplicate symbol %s"
1944 " (owned by %s)\n",
1945 mod->name, s->name, module_name(owner));
1946 return -ENOEXEC;
1947 }
1948 }
1949 }
1950 return 0;
1951}
1952
1953/* Change all symbols so that st_value encodes the pointer directly. */
1954static int simplify_symbols(struct module *mod, const struct load_info *info)
1955{
1956 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
1957 Elf_Sym *sym = (void *)symsec->sh_addr;
1958 unsigned long secbase;
1959 unsigned int i;
1960 int ret = 0;
1961 const struct kernel_symbol *ksym;
1962
1963 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
1964 const char *name = info->strtab + sym[i].st_name;
1965
1966 switch (sym[i].st_shndx) {
1967 case SHN_COMMON:
1968 /* We compiled with -fno-common. These are not
1969 supposed to happen. */
1970 pr_debug("Common symbol: %s\n", name);
1971 printk("%s: please compile with -fno-common\n",
1972 mod->name);
1973 ret = -ENOEXEC;
1974 break;
1975
1976 case SHN_ABS:
1977 /* Don't need to do anything */
1978 pr_debug("Absolute symbol: 0x%08lx\n",
1979 (long)sym[i].st_value);
1980 break;
1981
1982 case SHN_UNDEF:
1983 ksym = resolve_symbol_wait(mod, info, name);
1984 /* Ok if resolved. */
1985 if (ksym && !IS_ERR(ksym)) {
1986 sym[i].st_value = ksym->value;
1987 break;
1988 }
1989
1990 /* Ok if weak. */
1991 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1992 break;
1993
1994 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
1995 mod->name, name, PTR_ERR(ksym));
1996 ret = PTR_ERR(ksym) ?: -ENOENT;
1997 break;
1998
1999 default:
2000 /* Divert to percpu allocation if a percpu var. */
2001 if (sym[i].st_shndx == info->index.pcpu)
2002 secbase = (unsigned long)mod_percpu(mod);
2003 else
2004 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
2005 sym[i].st_value += secbase;
2006 break;
2007 }
2008 }
2009
2010 return ret;
2011}
2012
2013static int apply_relocations(struct module *mod, const struct load_info *info)
2014{
2015 unsigned int i;
2016 int err = 0;
2017
2018 /* Now do relocations. */
2019 for (i = 1; i < info->hdr->e_shnum; i++) {
2020 unsigned int infosec = info->sechdrs[i].sh_info;
2021
2022 /* Not a valid relocation section? */
2023 if (infosec >= info->hdr->e_shnum)
2024 continue;
2025
2026 /* Don't bother with non-allocated sections */
2027 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
2028 continue;
2029
2030 if (info->sechdrs[i].sh_type == SHT_REL)
2031 err = apply_relocate(info->sechdrs, info->strtab,
2032 info->index.sym, i, mod);
2033 else if (info->sechdrs[i].sh_type == SHT_RELA)
2034 err = apply_relocate_add(info->sechdrs, info->strtab,
2035 info->index.sym, i, mod);
2036 if (err < 0)
2037 break;
2038 }
2039 return err;
2040}
2041
2042/* Additional bytes needed by arch in front of individual sections */
2043unsigned int __weak arch_mod_section_prepend(struct module *mod,
2044 unsigned int section)
2045{
2046 /* default implementation just returns zero */
2047 return 0;
2048}
2049
2050/* Update size with this section: return offset. */
2051static long get_offset(struct module *mod, unsigned int *size,
2052 Elf_Shdr *sechdr, unsigned int section)
2053{
2054 long ret;
2055
2056 *size += arch_mod_section_prepend(mod, section);
2057 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2058 *size = ret + sechdr->sh_size;
2059 return ret;
2060}
2061
2062/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2063 might -- code, read-only data, read-write data, small data. Tally
2064 sizes, and place the offsets into sh_entsize fields: high bit means it
2065 belongs in init. */
2066static void layout_sections(struct module *mod, struct load_info *info)
2067{
2068 static unsigned long const masks[][2] = {
2069 /* NOTE: all executable code must be the first section
2070 * in this array; otherwise modify the text_size
2071 * finder in the two loops below */
2072 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2073 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
2074 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2075 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2076 };
2077 unsigned int m, i;
2078
2079 for (i = 0; i < info->hdr->e_shnum; i++)
2080 info->sechdrs[i].sh_entsize = ~0UL;
2081
2082 pr_debug("Core section allocation order:\n");
2083 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2084 for (i = 0; i < info->hdr->e_shnum; ++i) {
2085 Elf_Shdr *s = &info->sechdrs[i];
2086 const char *sname = info->secstrings + s->sh_name;
2087
2088 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2089 || (s->sh_flags & masks[m][1])
2090 || s->sh_entsize != ~0UL
2091 || strstarts(sname, ".init"))
2092 continue;
2093 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
2094 pr_debug("\t%s\n", sname);
2095 }
2096 switch (m) {
2097 case 0: /* executable */
2098 mod->core_size = debug_align(mod->core_size);
2099 mod->core_text_size = mod->core_size;
2100 break;
2101 case 1: /* RO: text and ro-data */
2102 mod->core_size = debug_align(mod->core_size);
2103 mod->core_ro_size = mod->core_size;
2104 break;
2105 case 3: /* whole core */
2106 mod->core_size = debug_align(mod->core_size);
2107 break;
2108 }
2109 }
2110
2111 pr_debug("Init section allocation order:\n");
2112 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2113 for (i = 0; i < info->hdr->e_shnum; ++i) {
2114 Elf_Shdr *s = &info->sechdrs[i];
2115 const char *sname = info->secstrings + s->sh_name;
2116
2117 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2118 || (s->sh_flags & masks[m][1])
2119 || s->sh_entsize != ~0UL
2120 || !strstarts(sname, ".init"))
2121 continue;
2122 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
2123 | INIT_OFFSET_MASK);
2124 pr_debug("\t%s\n", sname);
2125 }
2126 switch (m) {
2127 case 0: /* executable */
2128 mod->init_size = debug_align(mod->init_size);
2129 mod->init_text_size = mod->init_size;
2130 break;
2131 case 1: /* RO: text and ro-data */
2132 mod->init_size = debug_align(mod->init_size);
2133 mod->init_ro_size = mod->init_size;
2134 break;
2135 case 3: /* whole init */
2136 mod->init_size = debug_align(mod->init_size);
2137 break;
2138 }
2139 }
2140}
2141
2142static void set_license(struct module *mod, const char *license)
2143{
2144 if (!license)
2145 license = "unspecified";
2146
2147 if (!license_is_gpl_compatible(license)) {
2148 if (!test_taint(TAINT_PROPRIETARY_MODULE))
2149 printk(KERN_WARNING "%s: module license '%s' taints "
2150 "kernel.\n", mod->name, license);
2151 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2152 LOCKDEP_NOW_UNRELIABLE);
2153 }
2154}
2155
2156/* Parse tag=value strings from .modinfo section */
2157static char *next_string(char *string, unsigned long *secsize)
2158{
2159 /* Skip non-zero chars */
2160 while (string[0]) {
2161 string++;
2162 if ((*secsize)-- <= 1)
2163 return NULL;
2164 }
2165
2166 /* Skip any zero padding. */
2167 while (!string[0]) {
2168 string++;
2169 if ((*secsize)-- <= 1)
2170 return NULL;
2171 }
2172 return string;
2173}
2174
2175static char *get_modinfo(struct load_info *info, const char *tag)
2176{
2177 char *p;
2178 unsigned int taglen = strlen(tag);
2179 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2180 unsigned long size = infosec->sh_size;
2181
2182 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
2183 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2184 return p + taglen + 1;
2185 }
2186 return NULL;
2187}
2188
2189static void setup_modinfo(struct module *mod, struct load_info *info)
2190{
2191 struct module_attribute *attr;
2192 int i;
2193
2194 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2195 if (attr->setup)
2196 attr->setup(mod, get_modinfo(info, attr->attr.name));
2197 }
2198}
2199
2200static void free_modinfo(struct module *mod)
2201{
2202 struct module_attribute *attr;
2203 int i;
2204
2205 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2206 if (attr->free)
2207 attr->free(mod);
2208 }
2209}
2210
2211#ifdef CONFIG_KALLSYMS
2212
2213/* lookup symbol in given range of kernel_symbols */
2214static const struct kernel_symbol *lookup_symbol(const char *name,
2215 const struct kernel_symbol *start,
2216 const struct kernel_symbol *stop)
2217{
2218 return bsearch(name, start, stop - start,
2219 sizeof(struct kernel_symbol), cmp_name);
2220}
2221
2222static int is_exported(const char *name, unsigned long value,
2223 const struct module *mod)
2224{
2225 const struct kernel_symbol *ks;
2226 if (!mod)
2227 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
2228 else
2229 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
2230 return ks != NULL && ks->value == value;
2231}
2232
2233/* As per nm */
2234static char elf_type(const Elf_Sym *sym, const struct load_info *info)
2235{
2236 const Elf_Shdr *sechdrs = info->sechdrs;
2237
2238 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2239 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2240 return 'v';
2241 else
2242 return 'w';
2243 }
2244 if (sym->st_shndx == SHN_UNDEF)
2245 return 'U';
2246 if (sym->st_shndx == SHN_ABS)
2247 return 'a';
2248 if (sym->st_shndx >= SHN_LORESERVE)
2249 return '?';
2250 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2251 return 't';
2252 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2253 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2254 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2255 return 'r';
2256 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2257 return 'g';
2258 else
2259 return 'd';
2260 }
2261 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2262 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2263 return 's';
2264 else
2265 return 'b';
2266 }
2267 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2268 ".debug")) {
2269 return 'n';
2270 }
2271 return '?';
2272}
2273
2274static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
2275 unsigned int shnum)
2276{
2277 const Elf_Shdr *sec;
2278
2279 if (src->st_shndx == SHN_UNDEF
2280 || src->st_shndx >= shnum
2281 || !src->st_name)
2282 return false;
2283
2284 sec = sechdrs + src->st_shndx;
2285 if (!(sec->sh_flags & SHF_ALLOC)
2286#ifndef CONFIG_KALLSYMS_ALL
2287 || !(sec->sh_flags & SHF_EXECINSTR)
2288#endif
2289 || (sec->sh_entsize & INIT_OFFSET_MASK))
2290 return false;
2291
2292 return true;
2293}
2294
2295/*
2296 * We only allocate and copy the strings needed by the parts of symtab
2297 * we keep. This is simple, but has the effect of making multiple
2298 * copies of duplicates. We could be more sophisticated, see
2299 * linux-kernel thread starting with
2300 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2301 */
2302static void layout_symtab(struct module *mod, struct load_info *info)
2303{
2304 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2305 Elf_Shdr *strsect = info->sechdrs + info->index.str;
2306 const Elf_Sym *src;
2307 unsigned int i, nsrc, ndst, strtab_size = 0;
2308
2309 /* Put symbol section at end of init part of module. */
2310 symsect->sh_flags |= SHF_ALLOC;
2311 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
2312 info->index.sym) | INIT_OFFSET_MASK;
2313 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
2314
2315 src = (void *)info->hdr + symsect->sh_offset;
2316 nsrc = symsect->sh_size / sizeof(*src);
2317
2318 /* Compute total space required for the core symbols' strtab. */
2319 for (ndst = i = 0; i < nsrc; i++) {
2320 if (i == 0 ||
2321 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2322 strtab_size += strlen(&info->strtab[src[i].st_name])+1;
2323 ndst++;
2324 }
2325 }
2326
2327 /* Append room for core symbols at end of core part. */
2328 info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
2329 info->stroffs = mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym);
2330 mod->core_size += strtab_size;
2331
2332 /* Put string table section at end of init part of module. */
2333 strsect->sh_flags |= SHF_ALLOC;
2334 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
2335 info->index.str) | INIT_OFFSET_MASK;
2336 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
2337}
2338
2339static void add_kallsyms(struct module *mod, const struct load_info *info)
2340{
2341 unsigned int i, ndst;
2342 const Elf_Sym *src;
2343 Elf_Sym *dst;
2344 char *s;
2345 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2346
2347 mod->symtab = (void *)symsec->sh_addr;
2348 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2349 /* Make sure we get permanent strtab: don't use info->strtab. */
2350 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2351
2352 /* Set types up while we still have access to sections. */
2353 for (i = 0; i < mod->num_symtab; i++)
2354 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
2355
2356 mod->core_symtab = dst = mod->module_core + info->symoffs;
2357 mod->core_strtab = s = mod->module_core + info->stroffs;
2358 src = mod->symtab;
2359 for (ndst = i = 0; i < mod->num_symtab; i++) {
2360 if (i == 0 ||
2361 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2362 dst[ndst] = src[i];
2363 dst[ndst++].st_name = s - mod->core_strtab;
2364 s += strlcpy(s, &mod->strtab[src[i].st_name],
2365 KSYM_NAME_LEN) + 1;
2366 }
2367 }
2368 mod->core_num_syms = ndst;
2369}
2370#else
2371static inline void layout_symtab(struct module *mod, struct load_info *info)
2372{
2373}
2374
2375static void add_kallsyms(struct module *mod, const struct load_info *info)
2376{
2377}
2378#endif /* CONFIG_KALLSYMS */
2379
2380static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2381{
2382 if (!debug)
2383 return;
2384#ifdef CONFIG_DYNAMIC_DEBUG
2385 if (ddebug_add_module(debug, num, debug->modname))
2386 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2387 debug->modname);
2388#endif
2389}
2390
2391static void dynamic_debug_remove(struct _ddebug *debug)
2392{
2393 if (debug)
2394 ddebug_remove_module(debug->modname);
2395}
2396
2397void * __weak module_alloc(unsigned long size)
2398{
2399 return vmalloc_exec(size);
2400}
2401
2402static void *module_alloc_update_bounds(unsigned long size)
2403{
2404 void *ret = module_alloc(size);
2405
2406 if (ret) {
2407 mutex_lock(&module_mutex);
2408 /* Update module bounds. */
2409 if ((unsigned long)ret < module_addr_min)
2410 module_addr_min = (unsigned long)ret;
2411 if ((unsigned long)ret + size > module_addr_max)
2412 module_addr_max = (unsigned long)ret + size;
2413 mutex_unlock(&module_mutex);
2414 }
2415 return ret;
2416}
2417
2418#ifdef CONFIG_DEBUG_KMEMLEAK
2419static void kmemleak_load_module(const struct module *mod,
2420 const struct load_info *info)
2421{
2422 unsigned int i;
2423
2424 /* only scan the sections containing data */
2425 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2426
2427 for (i = 1; i < info->hdr->e_shnum; i++) {
2428 const char *name = info->secstrings + info->sechdrs[i].sh_name;
2429 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC))
2430 continue;
2431 if (!strstarts(name, ".data") && !strstarts(name, ".bss"))
2432 continue;
2433
2434 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2435 info->sechdrs[i].sh_size, GFP_KERNEL);
2436 }
2437}
2438#else
2439static inline void kmemleak_load_module(const struct module *mod,
2440 const struct load_info *info)
2441{
2442}
2443#endif
2444
2445#ifdef CONFIG_MODULE_SIG
2446static int module_sig_check(struct load_info *info)
2447{
2448 int err = -ENOKEY;
2449 const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2450 const void *mod = info->hdr;
2451
2452 if (info->len > markerlen &&
2453 memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
2454 /* We truncate the module to discard the signature */
2455 info->len -= markerlen;
2456 err = mod_verify_sig(mod, &info->len);
2457 }
2458
2459 if (!err) {
2460 info->sig_ok = true;
2461 return 0;
2462 }
2463
2464 /* Not having a signature is only an error if we're strict. */
2465 if (err < 0 && fips_enabled)
2466 panic("Module verification failed with error %d in FIPS mode\n",
2467 err);
2468 if (err == -ENOKEY && !sig_enforce)
2469 err = 0;
2470
2471 return err;
2472}
2473#else /* !CONFIG_MODULE_SIG */
2474static int module_sig_check(struct load_info *info)
2475{
2476 return 0;
2477}
2478#endif /* !CONFIG_MODULE_SIG */
2479
2480/* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2481static int elf_header_check(struct load_info *info)
2482{
2483 if (info->len < sizeof(*(info->hdr)))
2484 return -ENOEXEC;
2485
2486 if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2487 || info->hdr->e_type != ET_REL
2488 || !elf_check_arch(info->hdr)
2489 || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2490 return -ENOEXEC;
2491
2492 if (info->hdr->e_shoff >= info->len
2493 || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2494 info->len - info->hdr->e_shoff))
2495 return -ENOEXEC;
2496
2497 return 0;
2498}
2499
2500/* Sets info->hdr and info->len. */
2501static int copy_module_from_user(const void __user *umod, unsigned long len,
2502 struct load_info *info)
2503{
2504 int err;
2505
2506 info->len = len;
2507 if (info->len < sizeof(*(info->hdr)))
2508 return -ENOEXEC;
2509
2510 err = security_kernel_module_from_file(NULL);
2511 if (err)
2512 return err;
2513
2514 /* Suck in entire file: we'll want most of it. */
2515 info->hdr = vmalloc(info->len);
2516 if (!info->hdr)
2517 return -ENOMEM;
2518
2519 if (copy_from_user(info->hdr, umod, info->len) != 0) {
2520 vfree(info->hdr);
2521 return -EFAULT;
2522 }
2523
2524 return 0;
2525}
2526
2527/* Sets info->hdr and info->len. */
2528static int copy_module_from_fd(int fd, struct load_info *info)
2529{
2530 struct file *file;
2531 int err;
2532 struct kstat stat;
2533 loff_t pos;
2534 ssize_t bytes = 0;
2535
2536 file = fget(fd);
2537 if (!file)
2538 return -ENOEXEC;
2539
2540 err = security_kernel_module_from_file(file);
2541 if (err)
2542 goto out;
2543
2544 err = vfs_getattr(&file->f_path, &stat);
2545 if (err)
2546 goto out;
2547
2548 if (stat.size > INT_MAX) {
2549 err = -EFBIG;
2550 goto out;
2551 }
2552
2553 /* Don't hand 0 to vmalloc, it whines. */
2554 if (stat.size == 0) {
2555 err = -EINVAL;
2556 goto out;
2557 }
2558
2559 info->hdr = vmalloc(stat.size);
2560 if (!info->hdr) {
2561 err = -ENOMEM;
2562 goto out;
2563 }
2564
2565 pos = 0;
2566 while (pos < stat.size) {
2567 bytes = kernel_read(file, pos, (char *)(info->hdr) + pos,
2568 stat.size - pos);
2569 if (bytes < 0) {
2570 vfree(info->hdr);
2571 err = bytes;
2572 goto out;
2573 }
2574 if (bytes == 0)
2575 break;
2576 pos += bytes;
2577 }
2578 info->len = pos;
2579
2580out:
2581 fput(file);
2582 return err;
2583}
2584
2585static void free_copy(struct load_info *info)
2586{
2587 vfree(info->hdr);
2588}
2589
2590static int rewrite_section_headers(struct load_info *info, int flags)
2591{
2592 unsigned int i;
2593
2594 /* This should always be true, but let's be sure. */
2595 info->sechdrs[0].sh_addr = 0;
2596
2597 for (i = 1; i < info->hdr->e_shnum; i++) {
2598 Elf_Shdr *shdr = &info->sechdrs[i];
2599 if (shdr->sh_type != SHT_NOBITS
2600 && info->len < shdr->sh_offset + shdr->sh_size) {
2601 printk(KERN_ERR "Module len %lu truncated\n",
2602 info->len);
2603 return -ENOEXEC;
2604 }
2605
2606 /* Mark all sections sh_addr with their address in the
2607 temporary image. */
2608 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2609
2610#ifndef CONFIG_MODULE_UNLOAD
2611 /* Don't load .exit sections */
2612 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2613 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2614#endif
2615 }
2616
2617 /* Track but don't keep modinfo and version sections. */
2618 if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
2619 info->index.vers = 0; /* Pretend no __versions section! */
2620 else
2621 info->index.vers = find_sec(info, "__versions");
2622 info->index.info = find_sec(info, ".modinfo");
2623 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2624 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2625 return 0;
2626}
2627
2628/*
2629 * Set up our basic convenience variables (pointers to section headers,
2630 * search for module section index etc), and do some basic section
2631 * verification.
2632 *
2633 * Return the temporary module pointer (we'll replace it with the final
2634 * one when we move the module sections around).
2635 */
2636static struct module *setup_load_info(struct load_info *info, int flags)
2637{
2638 unsigned int i;
2639 int err;
2640 struct module *mod;
2641
2642 /* Set up the convenience variables */
2643 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2644 info->secstrings = (void *)info->hdr
2645 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2646
2647 err = rewrite_section_headers(info, flags);
2648 if (err)
2649 return ERR_PTR(err);
2650
2651 /* Find internal symbols and strings. */
2652 for (i = 1; i < info->hdr->e_shnum; i++) {
2653 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2654 info->index.sym = i;
2655 info->index.str = info->sechdrs[i].sh_link;
2656 info->strtab = (char *)info->hdr
2657 + info->sechdrs[info->index.str].sh_offset;
2658 break;
2659 }
2660 }
2661
2662 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
2663 if (!info->index.mod) {
2664 printk(KERN_WARNING "No module found in object\n");
2665 return ERR_PTR(-ENOEXEC);
2666 }
2667 /* This is temporary: point mod into copy of data. */
2668 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2669
2670 if (info->index.sym == 0) {
2671 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2672 mod->name);
2673 return ERR_PTR(-ENOEXEC);
2674 }
2675
2676 info->index.pcpu = find_pcpusec(info);
2677
2678 /* Check module struct version now, before we try to use module. */
2679 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2680 return ERR_PTR(-ENOEXEC);
2681
2682 return mod;
2683}
2684
2685static int check_modinfo(struct module *mod, struct load_info *info, int flags)
2686{
2687 const char *modmagic = get_modinfo(info, "vermagic");
2688 int err;
2689
2690 if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2691 modmagic = NULL;
2692
2693 /* This is allowed: modprobe --force will invalidate it. */
2694 if (!modmagic) {
2695 err = try_to_force_load(mod, "bad vermagic");
2696 if (err)
2697 return err;
2698 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2699 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2700 mod->name, modmagic, vermagic);
2701 return -ENOEXEC;
2702 }
2703
2704 if (!get_modinfo(info, "intree"))
2705 add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
2706
2707 if (get_modinfo(info, "staging")) {
2708 add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
2709 printk(KERN_WARNING "%s: module is from the staging directory,"
2710 " the quality is unknown, you have been warned.\n",
2711 mod->name);
2712 }
2713
2714 /* Set up license info based on the info section */
2715 set_license(mod, get_modinfo(info, "license"));
2716
2717 return 0;
2718}
2719
2720static void find_module_sections(struct module *mod, struct load_info *info)
2721{
2722 mod->kp = section_objs(info, "__param",
2723 sizeof(*mod->kp), &mod->num_kp);
2724 mod->syms = section_objs(info, "__ksymtab",
2725 sizeof(*mod->syms), &mod->num_syms);
2726 mod->crcs = section_addr(info, "__kcrctab");
2727 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2728 sizeof(*mod->gpl_syms),
2729 &mod->num_gpl_syms);
2730 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2731 mod->gpl_future_syms = section_objs(info,
2732 "__ksymtab_gpl_future",
2733 sizeof(*mod->gpl_future_syms),
2734 &mod->num_gpl_future_syms);
2735 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
2736
2737#ifdef CONFIG_UNUSED_SYMBOLS
2738 mod->unused_syms = section_objs(info, "__ksymtab_unused",
2739 sizeof(*mod->unused_syms),
2740 &mod->num_unused_syms);
2741 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2742 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
2743 sizeof(*mod->unused_gpl_syms),
2744 &mod->num_unused_gpl_syms);
2745 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
2746#endif
2747#ifdef CONFIG_CONSTRUCTORS
2748 mod->ctors = section_objs(info, ".ctors",
2749 sizeof(*mod->ctors), &mod->num_ctors);
2750#endif
2751
2752#ifdef CONFIG_TRACEPOINTS
2753 mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2754 sizeof(*mod->tracepoints_ptrs),
2755 &mod->num_tracepoints);
2756#endif
2757#ifdef HAVE_JUMP_LABEL
2758 mod->jump_entries = section_objs(info, "__jump_table",
2759 sizeof(*mod->jump_entries),
2760 &mod->num_jump_entries);
2761#endif
2762#ifdef CONFIG_EVENT_TRACING
2763 mod->trace_events = section_objs(info, "_ftrace_events",
2764 sizeof(*mod->trace_events),
2765 &mod->num_trace_events);
2766 /*
2767 * This section contains pointers to allocated objects in the trace
2768 * code and not scanning it leads to false positives.
2769 */
2770 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2771 mod->num_trace_events, GFP_KERNEL);
2772#endif
2773#ifdef CONFIG_TRACING
2774 mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2775 sizeof(*mod->trace_bprintk_fmt_start),
2776 &mod->num_trace_bprintk_fmt);
2777 /*
2778 * This section contains pointers to allocated objects in the trace
2779 * code and not scanning it leads to false positives.
2780 */
2781 kmemleak_scan_area(mod->trace_bprintk_fmt_start,
2782 sizeof(*mod->trace_bprintk_fmt_start) *
2783 mod->num_trace_bprintk_fmt, GFP_KERNEL);
2784#endif
2785#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2786 /* sechdrs[0].sh_size is always zero */
2787 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
2788 sizeof(*mod->ftrace_callsites),
2789 &mod->num_ftrace_callsites);
2790#endif
2791
2792 mod->extable = section_objs(info, "__ex_table",
2793 sizeof(*mod->extable), &mod->num_exentries);
2794
2795 if (section_addr(info, "__obsparm"))
2796 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2797 mod->name);
2798
2799 info->debug = section_objs(info, "__verbose",
2800 sizeof(*info->debug), &info->num_debug);
2801}
2802
2803static int move_module(struct module *mod, struct load_info *info)
2804{
2805 int i;
2806 void *ptr;
2807
2808 /* Do the allocs. */
2809 ptr = module_alloc_update_bounds(mod->core_size);
2810 /*
2811 * The pointer to this block is stored in the module structure
2812 * which is inside the block. Just mark it as not being a
2813 * leak.
2814 */
2815 kmemleak_not_leak(ptr);
2816 if (!ptr)
2817 return -ENOMEM;
2818
2819 memset(ptr, 0, mod->core_size);
2820 mod->module_core = ptr;
2821
2822 if (mod->init_size) {
2823 ptr = module_alloc_update_bounds(mod->init_size);
2824 /*
2825 * The pointer to this block is stored in the module structure
2826 * which is inside the block. This block doesn't need to be
2827 * scanned as it contains data and code that will be freed
2828 * after the module is initialized.
2829 */
2830 kmemleak_ignore(ptr);
2831 if (!ptr) {
2832 module_free(mod, mod->module_core);
2833 return -ENOMEM;
2834 }
2835 memset(ptr, 0, mod->init_size);
2836 mod->module_init = ptr;
2837 } else
2838 mod->module_init = NULL;
2839
2840 /* Transfer each section which specifies SHF_ALLOC */
2841 pr_debug("final section addresses:\n");
2842 for (i = 0; i < info->hdr->e_shnum; i++) {
2843 void *dest;
2844 Elf_Shdr *shdr = &info->sechdrs[i];
2845
2846 if (!(shdr->sh_flags & SHF_ALLOC))
2847 continue;
2848
2849 if (shdr->sh_entsize & INIT_OFFSET_MASK)
2850 dest = mod->module_init
2851 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
2852 else
2853 dest = mod->module_core + shdr->sh_entsize;
2854
2855 if (shdr->sh_type != SHT_NOBITS)
2856 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2857 /* Update sh_addr to point to copy in image. */
2858 shdr->sh_addr = (unsigned long)dest;
2859 pr_debug("\t0x%lx %s\n",
2860 (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
2861 }
2862
2863 return 0;
2864}
2865
2866static int check_module_license_and_versions(struct module *mod)
2867{
2868 /*
2869 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2870 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2871 * using GPL-only symbols it needs.
2872 */
2873 if (strcmp(mod->name, "ndiswrapper") == 0)
2874 add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
2875
2876 /* driverloader was caught wrongly pretending to be under GPL */
2877 if (strcmp(mod->name, "driverloader") == 0)
2878 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2879 LOCKDEP_NOW_UNRELIABLE);
2880
2881 /* lve claims to be GPL but upstream won't provide source */
2882 if (strcmp(mod->name, "lve") == 0)
2883 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2884 LOCKDEP_NOW_UNRELIABLE);
2885
2886#ifdef CONFIG_MODVERSIONS
2887 if ((mod->num_syms && !mod->crcs)
2888 || (mod->num_gpl_syms && !mod->gpl_crcs)
2889 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2890#ifdef CONFIG_UNUSED_SYMBOLS
2891 || (mod->num_unused_syms && !mod->unused_crcs)
2892 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2893#endif
2894 ) {
2895 return try_to_force_load(mod,
2896 "no versions for exported symbols");
2897 }
2898#endif
2899 return 0;
2900}
2901
2902static void flush_module_icache(const struct module *mod)
2903{
2904 mm_segment_t old_fs;
2905
2906 /* flush the icache in correct context */
2907 old_fs = get_fs();
2908 set_fs(KERNEL_DS);
2909
2910 /*
2911 * Flush the instruction cache, since we've played with text.
2912 * Do it before processing of module parameters, so the module
2913 * can provide parameter accessor functions of its own.
2914 */
2915 if (mod->module_init)
2916 flush_icache_range((unsigned long)mod->module_init,
2917 (unsigned long)mod->module_init
2918 + mod->init_size);
2919 flush_icache_range((unsigned long)mod->module_core,
2920 (unsigned long)mod->module_core + mod->core_size);
2921
2922 set_fs(old_fs);
2923}
2924
2925int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
2926 Elf_Shdr *sechdrs,
2927 char *secstrings,
2928 struct module *mod)
2929{
2930 return 0;
2931}
2932
2933static struct module *layout_and_allocate(struct load_info *info, int flags)
2934{
2935 /* Module within temporary copy. */
2936 struct module *mod;
2937 Elf_Shdr *pcpusec;
2938 int err;
2939
2940 mod = setup_load_info(info, flags);
2941 if (IS_ERR(mod))
2942 return mod;
2943
2944 err = check_modinfo(mod, info, flags);
2945 if (err)
2946 return ERR_PTR(err);
2947
2948 /* Allow arches to frob section contents and sizes. */
2949 err = module_frob_arch_sections(info->hdr, info->sechdrs,
2950 info->secstrings, mod);
2951 if (err < 0)
2952 goto out;
2953
2954 pcpusec = &info->sechdrs[info->index.pcpu];
2955 if (pcpusec->sh_size) {
2956 /* We have a special allocation for this section. */
2957 err = percpu_modalloc(mod,
2958 pcpusec->sh_size, pcpusec->sh_addralign);
2959 if (err)
2960 goto out;
2961 pcpusec->sh_flags &= ~(unsigned long)SHF_ALLOC;
2962 }
2963
2964 /* Determine total sizes, and put offsets in sh_entsize. For now
2965 this is done generically; there doesn't appear to be any
2966 special cases for the architectures. */
2967 layout_sections(mod, info);
2968 layout_symtab(mod, info);
2969
2970 /* Allocate and move to the final place */
2971 err = move_module(mod, info);
2972 if (err)
2973 goto free_percpu;
2974
2975 /* Module has been copied to its final place now: return it. */
2976 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2977 kmemleak_load_module(mod, info);
2978 return mod;
2979
2980free_percpu:
2981 percpu_modfree(mod);
2982out:
2983 return ERR_PTR(err);
2984}
2985
2986/* mod is no longer valid after this! */
2987static void module_deallocate(struct module *mod, struct load_info *info)
2988{
2989 percpu_modfree(mod);
2990 module_free(mod, mod->module_init);
2991 module_free(mod, mod->module_core);
2992}
2993
2994int __weak module_finalize(const Elf_Ehdr *hdr,
2995 const Elf_Shdr *sechdrs,
2996 struct module *me)
2997{
2998 return 0;
2999}
3000
3001static int post_relocation(struct module *mod, const struct load_info *info)
3002{
3003 /* Sort exception table now relocations are done. */
3004 sort_extable(mod->extable, mod->extable + mod->num_exentries);
3005
3006 /* Copy relocated percpu area over. */
3007 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
3008 info->sechdrs[info->index.pcpu].sh_size);
3009
3010 /* Setup kallsyms-specific fields. */
3011 add_kallsyms(mod, info);
3012
3013 /* Arch-specific module finalizing. */
3014 return module_finalize(info->hdr, info->sechdrs, mod);
3015}
3016
3017/* Is this module of this name done loading? No locks held. */
3018static bool finished_loading(const char *name)
3019{
3020 struct module *mod;
3021 bool ret;
3022
3023 mutex_lock(&module_mutex);
3024 mod = find_module_all(name, true);
3025 ret = !mod || mod->state == MODULE_STATE_LIVE
3026 || mod->state == MODULE_STATE_GOING;
3027 mutex_unlock(&module_mutex);
3028
3029 return ret;
3030}
3031
3032/* Call module constructors. */
3033static void do_mod_ctors(struct module *mod)
3034{
3035#ifdef CONFIG_CONSTRUCTORS
3036 unsigned long i;
3037
3038 for (i = 0; i < mod->num_ctors; i++)
3039 mod->ctors[i]();
3040#endif
3041}
3042
3043/* This is where the real work happens */
3044static int do_init_module(struct module *mod)
3045{
3046 int ret = 0;
3047
3048 /*
3049 * We want to find out whether @mod uses async during init. Clear
3050 * PF_USED_ASYNC. async_schedule*() will set it.
3051 */
3052 current->flags &= ~PF_USED_ASYNC;
3053
3054 blocking_notifier_call_chain(&module_notify_list,
3055 MODULE_STATE_COMING, mod);
3056
3057 /* Set RO and NX regions for core */
3058 set_section_ro_nx(mod->module_core,
3059 mod->core_text_size,
3060 mod->core_ro_size,
3061 mod->core_size);
3062
3063 /* Set RO and NX regions for init */
3064 set_section_ro_nx(mod->module_init,
3065 mod->init_text_size,
3066 mod->init_ro_size,
3067 mod->init_size);
3068
3069 do_mod_ctors(mod);
3070 /* Start the module */
3071 if (mod->init != NULL)
3072 ret = do_one_initcall(mod->init);
3073 if (ret < 0) {
3074 /* Init routine failed: abort. Try to protect us from
3075 buggy refcounters. */
3076 mod->state = MODULE_STATE_GOING;
3077 synchronize_sched();
3078 module_put(mod);
3079 blocking_notifier_call_chain(&module_notify_list,
3080 MODULE_STATE_GOING, mod);
3081 free_module(mod);
3082 wake_up_all(&module_wq);
3083 return ret;
3084 }
3085 if (ret > 0) {
3086 printk(KERN_WARNING
3087"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
3088"%s: loading module anyway...\n",
3089 __func__, mod->name, ret,
3090 __func__);
3091 dump_stack();
3092 }
3093
3094 /* Now it's a first class citizen! */
3095 mod->state = MODULE_STATE_LIVE;
3096 blocking_notifier_call_chain(&module_notify_list,
3097 MODULE_STATE_LIVE, mod);
3098
3099 /*
3100 * We need to finish all async code before the module init sequence
3101 * is done. This has potential to deadlock. For example, a newly
3102 * detected block device can trigger request_module() of the
3103 * default iosched from async probing task. Once userland helper
3104 * reaches here, async_synchronize_full() will wait on the async
3105 * task waiting on request_module() and deadlock.
3106 *
3107 * This deadlock is avoided by perfomring async_synchronize_full()
3108 * iff module init queued any async jobs. This isn't a full
3109 * solution as it will deadlock the same if module loading from
3110 * async jobs nests more than once; however, due to the various
3111 * constraints, this hack seems to be the best option for now.
3112 * Please refer to the following thread for details.
3113 *
3114 * http://thread.gmane.org/gmane.linux.kernel/1420814
3115 */
3116 if (current->flags & PF_USED_ASYNC)
3117 async_synchronize_full();
3118
3119 mutex_lock(&module_mutex);
3120 /* Drop initial reference. */
3121 module_put(mod);
3122 trim_init_extable(mod);
3123#ifdef CONFIG_KALLSYMS
3124 mod->num_symtab = mod->core_num_syms;
3125 mod->symtab = mod->core_symtab;
3126 mod->strtab = mod->core_strtab;
3127#endif
3128 unset_module_init_ro_nx(mod);
3129 module_free(mod, mod->module_init);
3130 mod->module_init = NULL;
3131 mod->init_size = 0;
3132 mod->init_ro_size = 0;
3133 mod->init_text_size = 0;
3134 mutex_unlock(&module_mutex);
3135 wake_up_all(&module_wq);
3136
3137 return 0;
3138}
3139
3140static int may_init_module(void)
3141{
3142 if (!capable(CAP_SYS_MODULE) || modules_disabled)
3143 return -EPERM;
3144
3145 return 0;
3146}
3147
3148/*
3149 * We try to place it in the list now to make sure it's unique before
3150 * we dedicate too many resources. In particular, temporary percpu
3151 * memory exhaustion.
3152 */
3153static int add_unformed_module(struct module *mod)
3154{
3155 int err;
3156 struct module *old;
3157
3158 mod->state = MODULE_STATE_UNFORMED;
3159
3160again:
3161 mutex_lock(&module_mutex);
3162 if ((old = find_module_all(mod->name, true)) != NULL) {
3163 if (old->state == MODULE_STATE_COMING
3164 || old->state == MODULE_STATE_UNFORMED) {
3165 /* Wait in case it fails to load. */
3166 mutex_unlock(&module_mutex);
3167 err = wait_event_interruptible(module_wq,
3168 finished_loading(mod->name));
3169 if (err)
3170 goto out_unlocked;
3171 goto again;
3172 }
3173 err = -EEXIST;
3174 goto out;
3175 }
3176 list_add_rcu(&mod->list, &modules);
3177 err = 0;
3178
3179out:
3180 mutex_unlock(&module_mutex);
3181out_unlocked:
3182 return err;
3183}
3184
3185static int complete_formation(struct module *mod, struct load_info *info)
3186{
3187 int err;
3188
3189 mutex_lock(&module_mutex);
3190
3191 /* Find duplicate symbols (must be called under lock). */
3192 err = verify_export_symbols(mod);
3193 if (err < 0)
3194 goto out;
3195
3196 /* This relies on module_mutex for list integrity. */
3197 module_bug_finalize(info->hdr, info->sechdrs, mod);
3198
3199 /* Mark state as coming so strong_try_module_get() ignores us,
3200 * but kallsyms etc. can see us. */
3201 mod->state = MODULE_STATE_COMING;
3202
3203out:
3204 mutex_unlock(&module_mutex);
3205 return err;
3206}
3207
3208/* Allocate and load the module: note that size of section 0 is always
3209 zero, and we rely on this for optional sections. */
3210static int load_module(struct load_info *info, const char __user *uargs,
3211 int flags)
3212{
3213 struct module *mod;
3214 long err;
3215
3216 err = module_sig_check(info);
3217 if (err)
3218 goto free_copy;
3219
3220 err = elf_header_check(info);
3221 if (err)
3222 goto free_copy;
3223
3224 /* Figure out module layout, and allocate all the memory. */
3225 mod = layout_and_allocate(info, flags);
3226 if (IS_ERR(mod)) {
3227 err = PTR_ERR(mod);
3228 goto free_copy;
3229 }
3230
3231 /* Reserve our place in the list. */
3232 err = add_unformed_module(mod);
3233 if (err)
3234 goto free_module;
3235
3236#ifdef CONFIG_MODULE_SIG
3237 mod->sig_ok = info->sig_ok;
3238 if (!mod->sig_ok) {
3239 printk_once(KERN_NOTICE
3240 "%s: module verification failed: signature and/or"
3241 " required key missing - tainting kernel\n",
3242 mod->name);
3243 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_STILL_OK);
3244 }
3245#endif
3246
3247 /* Now module is in final location, initialize linked lists, etc. */
3248 err = module_unload_init(mod);
3249 if (err)
3250 goto unlink_mod;
3251
3252 /* Now we've got everything in the final locations, we can
3253 * find optional sections. */
3254 find_module_sections(mod, info);
3255
3256 err = check_module_license_and_versions(mod);
3257 if (err)
3258 goto free_unload;
3259
3260 /* Set up MODINFO_ATTR fields */
3261 setup_modinfo(mod, info);
3262
3263 /* Fix up syms, so that st_value is a pointer to location. */
3264 err = simplify_symbols(mod, info);
3265 if (err < 0)
3266 goto free_modinfo;
3267
3268 err = apply_relocations(mod, info);
3269 if (err < 0)
3270 goto free_modinfo;
3271
3272 err = post_relocation(mod, info);
3273 if (err < 0)
3274 goto free_modinfo;
3275
3276 flush_module_icache(mod);
3277
3278 /* Now copy in args */
3279 mod->args = strndup_user(uargs, ~0UL >> 1);
3280 if (IS_ERR(mod->args)) {
3281 err = PTR_ERR(mod->args);
3282 goto free_arch_cleanup;
3283 }
3284
3285 dynamic_debug_setup(info->debug, info->num_debug);
3286
3287 /* Finally it's fully formed, ready to start executing. */
3288 err = complete_formation(mod, info);
3289 if (err)
3290 goto ddebug_cleanup;
3291
3292 /* Module is ready to execute: parsing args may do that. */
3293 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
3294 -32768, 32767, &ddebug_dyndbg_module_param_cb);
3295 if (err < 0)
3296 goto bug_cleanup;
3297
3298 /* Link in to syfs. */
3299 err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3300 if (err < 0)
3301 goto bug_cleanup;
3302
3303 /* Get rid of temporary copy. */
3304 free_copy(info);
3305
3306 /* Done! */
3307 trace_module_load(mod);
3308
3309 return do_init_module(mod);
3310
3311 bug_cleanup:
3312 /* module_bug_cleanup needs module_mutex protection */
3313 mutex_lock(&module_mutex);
3314 module_bug_cleanup(mod);
3315 mutex_unlock(&module_mutex);
3316 ddebug_cleanup:
3317 dynamic_debug_remove(info->debug);
3318 synchronize_sched();
3319 kfree(mod->args);
3320 free_arch_cleanup:
3321 module_arch_cleanup(mod);
3322 free_modinfo:
3323 free_modinfo(mod);
3324 free_unload:
3325 module_unload_free(mod);
3326 unlink_mod:
3327 mutex_lock(&module_mutex);
3328 /* Unlink carefully: kallsyms could be walking list. */
3329 list_del_rcu(&mod->list);
3330 wake_up_all(&module_wq);
3331 mutex_unlock(&module_mutex);
3332 free_module:
3333 module_deallocate(mod, info);
3334 free_copy:
3335 free_copy(info);
3336 return err;
3337}
3338
3339SYSCALL_DEFINE3(init_module, void __user *, umod,
3340 unsigned long, len, const char __user *, uargs)
3341{
3342 int err;
3343 struct load_info info = { };
3344
3345 err = may_init_module();
3346 if (err)
3347 return err;
3348
3349 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3350 umod, len, uargs);
3351
3352 err = copy_module_from_user(umod, len, &info);
3353 if (err)
3354 return err;
3355
3356 return load_module(&info, uargs, 0);
3357}
3358
3359SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3360{
3361 int err;
3362 struct load_info info = { };
3363
3364 err = may_init_module();
3365 if (err)
3366 return err;
3367
3368 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3369
3370 if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3371 |MODULE_INIT_IGNORE_VERMAGIC))
3372 return -EINVAL;
3373
3374 err = copy_module_from_fd(fd, &info);
3375 if (err)
3376 return err;
3377
3378 return load_module(&info, uargs, flags);
3379}
3380
3381static inline int within(unsigned long addr, void *start, unsigned long size)
3382{
3383 return ((void *)addr >= start && (void *)addr < start + size);
3384}
3385
3386#ifdef CONFIG_KALLSYMS
3387/*
3388 * This ignores the intensely annoying "mapping symbols" found
3389 * in ARM ELF files: $a, $t and $d.
3390 */
3391static inline int is_arm_mapping_symbol(const char *str)
3392{
3393 return str[0] == '$' && strchr("atd", str[1])
3394 && (str[2] == '\0' || str[2] == '.');
3395}
3396
3397static const char *get_ksymbol(struct module *mod,
3398 unsigned long addr,
3399 unsigned long *size,
3400 unsigned long *offset)
3401{
3402 unsigned int i, best = 0;
3403 unsigned long nextval;
3404
3405 /* At worse, next value is at end of module */
3406 if (within_module_init(addr, mod))
3407 nextval = (unsigned long)mod->module_init+mod->init_text_size;
3408 else
3409 nextval = (unsigned long)mod->module_core+mod->core_text_size;
3410
3411 /* Scan for closest preceding symbol, and next symbol. (ELF
3412 starts real symbols at 1). */
3413 for (i = 1; i < mod->num_symtab; i++) {
3414 if (mod->symtab[i].st_shndx == SHN_UNDEF)
3415 continue;
3416
3417 /* We ignore unnamed symbols: they're uninformative
3418 * and inserted at a whim. */
3419 if (mod->symtab[i].st_value <= addr
3420 && mod->symtab[i].st_value > mod->symtab[best].st_value
3421 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3422 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3423 best = i;
3424 if (mod->symtab[i].st_value > addr
3425 && mod->symtab[i].st_value < nextval
3426 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3427 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3428 nextval = mod->symtab[i].st_value;
3429 }
3430
3431 if (!best)
3432 return NULL;
3433
3434 if (size)
3435 *size = nextval - mod->symtab[best].st_value;
3436 if (offset)
3437 *offset = addr - mod->symtab[best].st_value;
3438 return mod->strtab + mod->symtab[best].st_name;
3439}
3440
3441/* For kallsyms to ask for address resolution. NULL means not found. Careful
3442 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3443const char *module_address_lookup(unsigned long addr,
3444 unsigned long *size,
3445 unsigned long *offset,
3446 char **modname,
3447 char *namebuf)
3448{
3449 struct module *mod;
3450 const char *ret = NULL;
3451
3452 preempt_disable();
3453 list_for_each_entry_rcu(mod, &modules, list) {
3454 if (mod->state == MODULE_STATE_UNFORMED)
3455 continue;
3456 if (within_module_init(addr, mod) ||
3457 within_module_core(addr, mod)) {
3458 if (modname)
3459 *modname = mod->name;
3460 ret = get_ksymbol(mod, addr, size, offset);
3461 break;
3462 }
3463 }
3464 /* Make a copy in here where it's safe */
3465 if (ret) {
3466 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
3467 ret = namebuf;
3468 }
3469 preempt_enable();
3470 return ret;
3471}
3472
3473int lookup_module_symbol_name(unsigned long addr, char *symname)
3474{
3475 struct module *mod;
3476
3477 preempt_disable();
3478 list_for_each_entry_rcu(mod, &modules, list) {
3479 if (mod->state == MODULE_STATE_UNFORMED)
3480 continue;
3481 if (within_module_init(addr, mod) ||
3482 within_module_core(addr, mod)) {
3483 const char *sym;
3484
3485 sym = get_ksymbol(mod, addr, NULL, NULL);
3486 if (!sym)
3487 goto out;
3488 strlcpy(symname, sym, KSYM_NAME_LEN);
3489 preempt_enable();
3490 return 0;
3491 }
3492 }
3493out:
3494 preempt_enable();
3495 return -ERANGE;
3496}
3497
3498int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
3499 unsigned long *offset, char *modname, char *name)
3500{
3501 struct module *mod;
3502
3503 preempt_disable();
3504 list_for_each_entry_rcu(mod, &modules, list) {
3505 if (mod->state == MODULE_STATE_UNFORMED)
3506 continue;
3507 if (within_module_init(addr, mod) ||
3508 within_module_core(addr, mod)) {
3509 const char *sym;
3510
3511 sym = get_ksymbol(mod, addr, size, offset);
3512 if (!sym)
3513 goto out;
3514 if (modname)
3515 strlcpy(modname, mod->name, MODULE_NAME_LEN);
3516 if (name)
3517 strlcpy(name, sym, KSYM_NAME_LEN);
3518 preempt_enable();
3519 return 0;
3520 }
3521 }
3522out:
3523 preempt_enable();
3524 return -ERANGE;
3525}
3526
3527int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
3528 char *name, char *module_name, int *exported)
3529{
3530 struct module *mod;
3531
3532 preempt_disable();
3533 list_for_each_entry_rcu(mod, &modules, list) {
3534 if (mod->state == MODULE_STATE_UNFORMED)
3535 continue;
3536 if (symnum < mod->num_symtab) {
3537 *value = mod->symtab[symnum].st_value;
3538 *type = mod->symtab[symnum].st_info;
3539 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
3540 KSYM_NAME_LEN);
3541 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
3542 *exported = is_exported(name, *value, mod);
3543 preempt_enable();
3544 return 0;
3545 }
3546 symnum -= mod->num_symtab;
3547 }
3548 preempt_enable();
3549 return -ERANGE;
3550}
3551
3552static unsigned long mod_find_symname(struct module *mod, const char *name)
3553{
3554 unsigned int i;
3555
3556 for (i = 0; i < mod->num_symtab; i++)
3557 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
3558 mod->symtab[i].st_info != 'U')
3559 return mod->symtab[i].st_value;
3560 return 0;
3561}
3562
3563/* Look for this name: can be of form module:name. */
3564unsigned long module_kallsyms_lookup_name(const char *name)
3565{
3566 struct module *mod;
3567 char *colon;
3568 unsigned long ret = 0;
3569
3570 /* Don't lock: we're in enough trouble already. */
3571 preempt_disable();
3572 if ((colon = strchr(name, ':')) != NULL) {
3573 *colon = '\0';
3574 if ((mod = find_module(name)) != NULL)
3575 ret = mod_find_symname(mod, colon+1);
3576 *colon = ':';
3577 } else {
3578 list_for_each_entry_rcu(mod, &modules, list) {
3579 if (mod->state == MODULE_STATE_UNFORMED)
3580 continue;
3581 if ((ret = mod_find_symname(mod, name)) != 0)
3582 break;
3583 }
3584 }
3585 preempt_enable();
3586 return ret;
3587}
3588
3589int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3590 struct module *, unsigned long),
3591 void *data)
3592{
3593 struct module *mod;
3594 unsigned int i;
3595 int ret;
3596
3597 list_for_each_entry(mod, &modules, list) {
3598 if (mod->state == MODULE_STATE_UNFORMED)
3599 continue;
3600 for (i = 0; i < mod->num_symtab; i++) {
3601 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
3602 mod, mod->symtab[i].st_value);
3603 if (ret != 0)
3604 return ret;
3605 }
3606 }
3607 return 0;
3608}
3609#endif /* CONFIG_KALLSYMS */
3610
3611static char *module_flags(struct module *mod, char *buf)
3612{
3613 int bx = 0;
3614
3615 BUG_ON(mod->state == MODULE_STATE_UNFORMED);
3616 if (mod->taints ||
3617 mod->state == MODULE_STATE_GOING ||
3618 mod->state == MODULE_STATE_COMING) {
3619 buf[bx++] = '(';
3620 bx += module_flags_taint(mod, buf + bx);
3621 /* Show a - for module-is-being-unloaded */
3622 if (mod->state == MODULE_STATE_GOING)
3623 buf[bx++] = '-';
3624 /* Show a + for module-is-being-loaded */
3625 if (mod->state == MODULE_STATE_COMING)
3626 buf[bx++] = '+';
3627 buf[bx++] = ')';
3628 }
3629 buf[bx] = '\0';
3630
3631 return buf;
3632}
3633
3634#ifdef CONFIG_PROC_FS
3635/* Called by the /proc file system to return a list of modules. */
3636static void *m_start(struct seq_file *m, loff_t *pos)
3637{
3638 mutex_lock(&module_mutex);
3639 return seq_list_start(&modules, *pos);
3640}
3641
3642static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3643{
3644 return seq_list_next(p, &modules, pos);
3645}
3646
3647static void m_stop(struct seq_file *m, void *p)
3648{
3649 mutex_unlock(&module_mutex);
3650}
3651
3652static int m_show(struct seq_file *m, void *p)
3653{
3654 struct module *mod = list_entry(p, struct module, list);
3655 char buf[8];
3656
3657 /* We always ignore unformed modules. */
3658 if (mod->state == MODULE_STATE_UNFORMED)
3659 return 0;
3660
3661 seq_printf(m, "%s %u",
3662 mod->name, mod->init_size + mod->core_size);
3663 print_unload_info(m, mod);
3664
3665 /* Informative for users. */
3666 seq_printf(m, " %s",
3667 mod->state == MODULE_STATE_GOING ? "Unloading":
3668 mod->state == MODULE_STATE_COMING ? "Loading":
3669 "Live");
3670 /* Used by oprofile and other similar tools. */
3671 seq_printf(m, " 0x%pK", mod->module_core);
3672
3673 /* Taints info */
3674 if (mod->taints)
3675 seq_printf(m, " %s", module_flags(mod, buf));
3676
3677 seq_printf(m, "\n");
3678 return 0;
3679}
3680
3681/* Format: modulename size refcount deps address
3682
3683 Where refcount is a number or -, and deps is a comma-separated list
3684 of depends or -.
3685*/
3686static const struct seq_operations modules_op = {
3687 .start = m_start,
3688 .next = m_next,
3689 .stop = m_stop,
3690 .show = m_show
3691};
3692
3693static int modules_open(struct inode *inode, struct file *file)
3694{
3695 return seq_open(file, &modules_op);
3696}
3697
3698static const struct file_operations proc_modules_operations = {
3699 .open = modules_open,
3700 .read = seq_read,
3701 .llseek = seq_lseek,
3702 .release = seq_release,
3703};
3704
3705static int __init proc_modules_init(void)
3706{
3707 proc_create("modules", 0, NULL, &proc_modules_operations);
3708 return 0;
3709}
3710module_init(proc_modules_init);
3711#endif
3712
3713/* Given an address, look for it in the module exception tables. */
3714const struct exception_table_entry *search_module_extables(unsigned long addr)
3715{
3716 const struct exception_table_entry *e = NULL;
3717 struct module *mod;
3718
3719 preempt_disable();
3720 list_for_each_entry_rcu(mod, &modules, list) {
3721 if (mod->state == MODULE_STATE_UNFORMED)
3722 continue;
3723 if (mod->num_exentries == 0)
3724 continue;
3725
3726 e = search_extable(mod->extable,
3727 mod->extable + mod->num_exentries - 1,
3728 addr);
3729 if (e)
3730 break;
3731 }
3732 preempt_enable();
3733
3734 /* Now, if we found one, we are running inside it now, hence
3735 we cannot unload the module, hence no refcnt needed. */
3736 return e;
3737}
3738
3739/*
3740 * is_module_address - is this address inside a module?
3741 * @addr: the address to check.
3742 *
3743 * See is_module_text_address() if you simply want to see if the address
3744 * is code (not data).
3745 */
3746bool is_module_address(unsigned long addr)
3747{
3748 bool ret;
3749
3750 preempt_disable();
3751 ret = __module_address(addr) != NULL;
3752 preempt_enable();
3753
3754 return ret;
3755}
3756
3757/*
3758 * __module_address - get the module which contains an address.
3759 * @addr: the address.
3760 *
3761 * Must be called with preempt disabled or module mutex held so that
3762 * module doesn't get freed during this.
3763 */
3764struct module *__module_address(unsigned long addr)
3765{
3766 struct module *mod;
3767
3768 if (addr < module_addr_min || addr > module_addr_max)
3769 return NULL;
3770
3771 list_for_each_entry_rcu(mod, &modules, list) {
3772 if (mod->state == MODULE_STATE_UNFORMED)
3773 continue;
3774 if (within_module_core(addr, mod)
3775 || within_module_init(addr, mod))
3776 return mod;
3777 }
3778 return NULL;
3779}
3780EXPORT_SYMBOL_GPL(__module_address);
3781
3782/*
3783 * is_module_text_address - is this address inside module code?
3784 * @addr: the address to check.
3785 *
3786 * See is_module_address() if you simply want to see if the address is
3787 * anywhere in a module. See kernel_text_address() for testing if an
3788 * address corresponds to kernel or module code.
3789 */
3790bool is_module_text_address(unsigned long addr)
3791{
3792 bool ret;
3793
3794 preempt_disable();
3795 ret = __module_text_address(addr) != NULL;
3796 preempt_enable();
3797
3798 return ret;
3799}
3800
3801/*
3802 * __module_text_address - get the module whose code contains an address.
3803 * @addr: the address.
3804 *
3805 * Must be called with preempt disabled or module mutex held so that
3806 * module doesn't get freed during this.
3807 */
3808struct module *__module_text_address(unsigned long addr)
3809{
3810 struct module *mod = __module_address(addr);
3811 if (mod) {
3812 /* Make sure it's within the text section. */
3813 if (!within(addr, mod->module_init, mod->init_text_size)
3814 && !within(addr, mod->module_core, mod->core_text_size))
3815 mod = NULL;
3816 }
3817 return mod;
3818}
3819EXPORT_SYMBOL_GPL(__module_text_address);
3820
3821/* Don't grab lock, we're oopsing. */
3822void print_modules(void)
3823{
3824 struct module *mod;
3825 char buf[8];
3826
3827 printk(KERN_DEFAULT "Modules linked in:");
3828 /* Most callers should already have preempt disabled, but make sure */
3829 preempt_disable();
3830 list_for_each_entry_rcu(mod, &modules, list) {
3831 if (mod->state == MODULE_STATE_UNFORMED)
3832 continue;
3833 printk(" %s%s", mod->name, module_flags(mod, buf));
3834 }
3835 preempt_enable();
3836 if (last_unloaded_module[0])
3837 printk(" [last unloaded: %s]", last_unloaded_module);
3838 printk("\n");
3839}
3840
3841#ifdef CONFIG_MODVERSIONS
3842/* Generate the signature for all relevant module structures here.
3843 * If these change, we don't want to try to parse the module. */
3844void module_layout(struct module *mod,
3845 struct modversion_info *ver,
3846 struct kernel_param *kp,
3847 struct kernel_symbol *ks,
3848 struct tracepoint * const *tp)
3849{
3850}
3851EXPORT_SYMBOL(module_layout);
3852#endif