x86/xen: resume timer irqs early
[linux/fpc-iii.git] / kernel / module.c
blob7b15ff67c5aa456c25bf482fb5a77479ac92371c
1 /*
2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
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.
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.
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
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"
67 #define CREATE_TRACE_POINTS
68 #include <trace/events/module.h>
70 #ifndef ARCH_SHF_SMALL
71 #define ARCH_SHF_SMALL 0
72 #endif
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
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
86 * Given BASE and SIZE this macro calculates the number of pages the
87 * memory regions occupies
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))
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))
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). */
103 DEFINE_MUTEX(module_mutex);
104 EXPORT_SYMBOL_GPL(module_mutex);
105 static LIST_HEAD(modules);
106 #ifdef CONFIG_KGDB_KDB
107 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
108 #endif /* CONFIG_KGDB_KDB */
110 #ifdef CONFIG_MODULE_SIG
111 #ifdef CONFIG_MODULE_SIG_FORCE
112 static bool sig_enforce = true;
113 #else
114 static bool sig_enforce = false;
116 static int param_set_bool_enable_only(const char *val,
117 const struct kernel_param *kp)
119 int err;
120 bool test;
121 struct kernel_param dummy_kp = *kp;
123 dummy_kp.arg = &test;
125 err = param_set_bool(val, &dummy_kp);
126 if (err)
127 return err;
129 /* Don't let them unset it once it's set! */
130 if (!test && sig_enforce)
131 return -EROFS;
133 if (test)
134 sig_enforce = true;
135 return 0;
138 static const struct kernel_param_ops param_ops_bool_enable_only = {
139 .flags = KERNEL_PARAM_FL_NOARG,
140 .set = param_set_bool_enable_only,
141 .get = param_get_bool,
143 #define param_check_bool_enable_only param_check_bool
145 module_param(sig_enforce, bool_enable_only, 0644);
146 #endif /* !CONFIG_MODULE_SIG_FORCE */
147 #endif /* CONFIG_MODULE_SIG */
149 /* Block module loading/unloading? */
150 int modules_disabled = 0;
151 core_param(nomodule, modules_disabled, bint, 0);
153 /* Waiting for a module to finish initializing? */
154 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
156 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
158 /* Bounds of module allocation, for speeding __module_address.
159 * Protected by module_mutex. */
160 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
162 int register_module_notifier(struct notifier_block * nb)
164 return blocking_notifier_chain_register(&module_notify_list, nb);
166 EXPORT_SYMBOL(register_module_notifier);
168 int unregister_module_notifier(struct notifier_block * nb)
170 return blocking_notifier_chain_unregister(&module_notify_list, nb);
172 EXPORT_SYMBOL(unregister_module_notifier);
174 struct load_info {
175 Elf_Ehdr *hdr;
176 unsigned long len;
177 Elf_Shdr *sechdrs;
178 char *secstrings, *strtab;
179 unsigned long symoffs, stroffs;
180 struct _ddebug *debug;
181 unsigned int num_debug;
182 bool sig_ok;
183 struct {
184 unsigned int sym, str, mod, vers, info, pcpu;
185 } index;
188 /* We require a truly strong try_module_get(): 0 means failure due to
189 ongoing or failed initialization etc. */
190 static inline int strong_try_module_get(struct module *mod)
192 BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
193 if (mod && mod->state == MODULE_STATE_COMING)
194 return -EBUSY;
195 if (try_module_get(mod))
196 return 0;
197 else
198 return -ENOENT;
201 static inline void add_taint_module(struct module *mod, unsigned flag,
202 enum lockdep_ok lockdep_ok)
204 add_taint(flag, lockdep_ok);
205 mod->taints |= (1U << flag);
209 * A thread that wants to hold a reference to a module only while it
210 * is running can call this to safely exit. nfsd and lockd use this.
212 void __module_put_and_exit(struct module *mod, long code)
214 module_put(mod);
215 do_exit(code);
217 EXPORT_SYMBOL(__module_put_and_exit);
219 /* Find a module section: 0 means not found. */
220 static unsigned int find_sec(const struct load_info *info, const char *name)
222 unsigned int i;
224 for (i = 1; i < info->hdr->e_shnum; i++) {
225 Elf_Shdr *shdr = &info->sechdrs[i];
226 /* Alloc bit cleared means "ignore it." */
227 if ((shdr->sh_flags & SHF_ALLOC)
228 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
229 return i;
231 return 0;
234 /* Find a module section, or NULL. */
235 static void *section_addr(const struct load_info *info, const char *name)
237 /* Section 0 has sh_addr 0. */
238 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
241 /* Find a module section, or NULL. Fill in number of "objects" in section. */
242 static void *section_objs(const struct load_info *info,
243 const char *name,
244 size_t object_size,
245 unsigned int *num)
247 unsigned int sec = find_sec(info, name);
249 /* Section 0 has sh_addr 0 and sh_size 0. */
250 *num = info->sechdrs[sec].sh_size / object_size;
251 return (void *)info->sechdrs[sec].sh_addr;
254 /* Provided by the linker */
255 extern const struct kernel_symbol __start___ksymtab[];
256 extern const struct kernel_symbol __stop___ksymtab[];
257 extern const struct kernel_symbol __start___ksymtab_gpl[];
258 extern const struct kernel_symbol __stop___ksymtab_gpl[];
259 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
260 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
261 extern const unsigned long __start___kcrctab[];
262 extern const unsigned long __start___kcrctab_gpl[];
263 extern const unsigned long __start___kcrctab_gpl_future[];
264 #ifdef CONFIG_UNUSED_SYMBOLS
265 extern const struct kernel_symbol __start___ksymtab_unused[];
266 extern const struct kernel_symbol __stop___ksymtab_unused[];
267 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
268 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
269 extern const unsigned long __start___kcrctab_unused[];
270 extern const unsigned long __start___kcrctab_unused_gpl[];
271 #endif
273 #ifndef CONFIG_MODVERSIONS
274 #define symversion(base, idx) NULL
275 #else
276 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
277 #endif
279 static bool each_symbol_in_section(const struct symsearch *arr,
280 unsigned int arrsize,
281 struct module *owner,
282 bool (*fn)(const struct symsearch *syms,
283 struct module *owner,
284 void *data),
285 void *data)
287 unsigned int j;
289 for (j = 0; j < arrsize; j++) {
290 if (fn(&arr[j], owner, data))
291 return true;
294 return false;
297 /* Returns true as soon as fn returns true, otherwise false. */
298 bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
299 struct module *owner,
300 void *data),
301 void *data)
303 struct module *mod;
304 static const struct symsearch arr[] = {
305 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
306 NOT_GPL_ONLY, false },
307 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
308 __start___kcrctab_gpl,
309 GPL_ONLY, false },
310 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
311 __start___kcrctab_gpl_future,
312 WILL_BE_GPL_ONLY, false },
313 #ifdef CONFIG_UNUSED_SYMBOLS
314 { __start___ksymtab_unused, __stop___ksymtab_unused,
315 __start___kcrctab_unused,
316 NOT_GPL_ONLY, true },
317 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
318 __start___kcrctab_unused_gpl,
319 GPL_ONLY, true },
320 #endif
323 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
324 return true;
326 list_for_each_entry_rcu(mod, &modules, list) {
327 struct symsearch arr[] = {
328 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
329 NOT_GPL_ONLY, false },
330 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
331 mod->gpl_crcs,
332 GPL_ONLY, false },
333 { mod->gpl_future_syms,
334 mod->gpl_future_syms + mod->num_gpl_future_syms,
335 mod->gpl_future_crcs,
336 WILL_BE_GPL_ONLY, false },
337 #ifdef CONFIG_UNUSED_SYMBOLS
338 { mod->unused_syms,
339 mod->unused_syms + mod->num_unused_syms,
340 mod->unused_crcs,
341 NOT_GPL_ONLY, true },
342 { mod->unused_gpl_syms,
343 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
344 mod->unused_gpl_crcs,
345 GPL_ONLY, true },
346 #endif
349 if (mod->state == MODULE_STATE_UNFORMED)
350 continue;
352 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
353 return true;
355 return false;
357 EXPORT_SYMBOL_GPL(each_symbol_section);
359 struct find_symbol_arg {
360 /* Input */
361 const char *name;
362 bool gplok;
363 bool warn;
365 /* Output */
366 struct module *owner;
367 const unsigned long *crc;
368 const struct kernel_symbol *sym;
371 static bool check_symbol(const struct symsearch *syms,
372 struct module *owner,
373 unsigned int symnum, void *data)
375 struct find_symbol_arg *fsa = data;
377 if (!fsa->gplok) {
378 if (syms->licence == GPL_ONLY)
379 return false;
380 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
381 printk(KERN_WARNING "Symbol %s is being used "
382 "by a non-GPL module, which will not "
383 "be allowed in the future\n", fsa->name);
387 #ifdef CONFIG_UNUSED_SYMBOLS
388 if (syms->unused && fsa->warn) {
389 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
390 "however this module is using it.\n", fsa->name);
391 printk(KERN_WARNING
392 "This symbol will go away in the future.\n");
393 printk(KERN_WARNING
394 "Please evalute if this is the right api to use and if "
395 "it really is, submit a report the linux kernel "
396 "mailinglist together with submitting your code for "
397 "inclusion.\n");
399 #endif
401 fsa->owner = owner;
402 fsa->crc = symversion(syms->crcs, symnum);
403 fsa->sym = &syms->start[symnum];
404 return true;
407 static int cmp_name(const void *va, const void *vb)
409 const char *a;
410 const struct kernel_symbol *b;
411 a = va; b = vb;
412 return strcmp(a, b->name);
415 static bool find_symbol_in_section(const struct symsearch *syms,
416 struct module *owner,
417 void *data)
419 struct find_symbol_arg *fsa = data;
420 struct kernel_symbol *sym;
422 sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
423 sizeof(struct kernel_symbol), cmp_name);
425 if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
426 return true;
428 return false;
431 /* Find a symbol and return it, along with, (optional) crc and
432 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
433 const struct kernel_symbol *find_symbol(const char *name,
434 struct module **owner,
435 const unsigned long **crc,
436 bool gplok,
437 bool warn)
439 struct find_symbol_arg fsa;
441 fsa.name = name;
442 fsa.gplok = gplok;
443 fsa.warn = warn;
445 if (each_symbol_section(find_symbol_in_section, &fsa)) {
446 if (owner)
447 *owner = fsa.owner;
448 if (crc)
449 *crc = fsa.crc;
450 return fsa.sym;
453 pr_debug("Failed to find symbol %s\n", name);
454 return NULL;
456 EXPORT_SYMBOL_GPL(find_symbol);
458 /* Search for module by name: must hold module_mutex. */
459 static struct module *find_module_all(const char *name, size_t len,
460 bool even_unformed)
462 struct module *mod;
464 list_for_each_entry(mod, &modules, list) {
465 if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
466 continue;
467 if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
468 return mod;
470 return NULL;
473 struct module *find_module(const char *name)
475 return find_module_all(name, strlen(name), false);
477 EXPORT_SYMBOL_GPL(find_module);
479 #ifdef CONFIG_SMP
481 static inline void __percpu *mod_percpu(struct module *mod)
483 return mod->percpu;
486 static int percpu_modalloc(struct module *mod, struct load_info *info)
488 Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
489 unsigned long align = pcpusec->sh_addralign;
491 if (!pcpusec->sh_size)
492 return 0;
494 if (align > PAGE_SIZE) {
495 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
496 mod->name, align, PAGE_SIZE);
497 align = PAGE_SIZE;
500 mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
501 if (!mod->percpu) {
502 printk(KERN_WARNING
503 "%s: Could not allocate %lu bytes percpu data\n",
504 mod->name, (unsigned long)pcpusec->sh_size);
505 return -ENOMEM;
507 mod->percpu_size = pcpusec->sh_size;
508 return 0;
511 static void percpu_modfree(struct module *mod)
513 free_percpu(mod->percpu);
516 static unsigned int find_pcpusec(struct load_info *info)
518 return find_sec(info, ".data..percpu");
521 static void percpu_modcopy(struct module *mod,
522 const void *from, unsigned long size)
524 int cpu;
526 for_each_possible_cpu(cpu)
527 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
531 * is_module_percpu_address - test whether address is from module static percpu
532 * @addr: address to test
534 * Test whether @addr belongs to module static percpu area.
536 * RETURNS:
537 * %true if @addr is from module static percpu area
539 bool is_module_percpu_address(unsigned long addr)
541 struct module *mod;
542 unsigned int cpu;
544 preempt_disable();
546 list_for_each_entry_rcu(mod, &modules, list) {
547 if (mod->state == MODULE_STATE_UNFORMED)
548 continue;
549 if (!mod->percpu_size)
550 continue;
551 for_each_possible_cpu(cpu) {
552 void *start = per_cpu_ptr(mod->percpu, cpu);
554 if ((void *)addr >= start &&
555 (void *)addr < start + mod->percpu_size) {
556 preempt_enable();
557 return true;
562 preempt_enable();
563 return false;
566 #else /* ... !CONFIG_SMP */
568 static inline void __percpu *mod_percpu(struct module *mod)
570 return NULL;
572 static int percpu_modalloc(struct module *mod, struct load_info *info)
574 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
575 if (info->sechdrs[info->index.pcpu].sh_size != 0)
576 return -ENOMEM;
577 return 0;
579 static inline void percpu_modfree(struct module *mod)
582 static unsigned int find_pcpusec(struct load_info *info)
584 return 0;
586 static inline void percpu_modcopy(struct module *mod,
587 const void *from, unsigned long size)
589 /* pcpusec should be 0, and size of that section should be 0. */
590 BUG_ON(size != 0);
592 bool is_module_percpu_address(unsigned long addr)
594 return false;
597 #endif /* CONFIG_SMP */
599 #define MODINFO_ATTR(field) \
600 static void setup_modinfo_##field(struct module *mod, const char *s) \
602 mod->field = kstrdup(s, GFP_KERNEL); \
604 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
605 struct module_kobject *mk, char *buffer) \
607 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
609 static int modinfo_##field##_exists(struct module *mod) \
611 return mod->field != NULL; \
613 static void free_modinfo_##field(struct module *mod) \
615 kfree(mod->field); \
616 mod->field = NULL; \
618 static struct module_attribute modinfo_##field = { \
619 .attr = { .name = __stringify(field), .mode = 0444 }, \
620 .show = show_modinfo_##field, \
621 .setup = setup_modinfo_##field, \
622 .test = modinfo_##field##_exists, \
623 .free = free_modinfo_##field, \
626 MODINFO_ATTR(version);
627 MODINFO_ATTR(srcversion);
629 static char last_unloaded_module[MODULE_NAME_LEN+1];
631 #ifdef CONFIG_MODULE_UNLOAD
633 EXPORT_TRACEPOINT_SYMBOL(module_get);
635 /* Init the unload section of the module. */
636 static int module_unload_init(struct module *mod)
638 mod->refptr = alloc_percpu(struct module_ref);
639 if (!mod->refptr)
640 return -ENOMEM;
642 INIT_LIST_HEAD(&mod->source_list);
643 INIT_LIST_HEAD(&mod->target_list);
645 /* Hold reference count during initialization. */
646 __this_cpu_write(mod->refptr->incs, 1);
647 /* Backwards compatibility macros put refcount during init. */
648 mod->waiter = current;
650 return 0;
653 /* Does a already use b? */
654 static int already_uses(struct module *a, struct module *b)
656 struct module_use *use;
658 list_for_each_entry(use, &b->source_list, source_list) {
659 if (use->source == a) {
660 pr_debug("%s uses %s!\n", a->name, b->name);
661 return 1;
664 pr_debug("%s does not use %s!\n", a->name, b->name);
665 return 0;
669 * Module a uses b
670 * - we add 'a' as a "source", 'b' as a "target" of module use
671 * - the module_use is added to the list of 'b' sources (so
672 * 'b' can walk the list to see who sourced them), and of 'a'
673 * targets (so 'a' can see what modules it targets).
675 static int add_module_usage(struct module *a, struct module *b)
677 struct module_use *use;
679 pr_debug("Allocating new usage for %s.\n", a->name);
680 use = kmalloc(sizeof(*use), GFP_ATOMIC);
681 if (!use) {
682 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
683 return -ENOMEM;
686 use->source = a;
687 use->target = b;
688 list_add(&use->source_list, &b->source_list);
689 list_add(&use->target_list, &a->target_list);
690 return 0;
693 /* Module a uses b: caller needs module_mutex() */
694 int ref_module(struct module *a, struct module *b)
696 int err;
698 if (b == NULL || already_uses(a, b))
699 return 0;
701 /* If module isn't available, we fail. */
702 err = strong_try_module_get(b);
703 if (err)
704 return err;
706 err = add_module_usage(a, b);
707 if (err) {
708 module_put(b);
709 return err;
711 return 0;
713 EXPORT_SYMBOL_GPL(ref_module);
715 /* Clear the unload stuff of the module. */
716 static void module_unload_free(struct module *mod)
718 struct module_use *use, *tmp;
720 mutex_lock(&module_mutex);
721 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
722 struct module *i = use->target;
723 pr_debug("%s unusing %s\n", mod->name, i->name);
724 module_put(i);
725 list_del(&use->source_list);
726 list_del(&use->target_list);
727 kfree(use);
729 mutex_unlock(&module_mutex);
731 free_percpu(mod->refptr);
734 #ifdef CONFIG_MODULE_FORCE_UNLOAD
735 static inline int try_force_unload(unsigned int flags)
737 int ret = (flags & O_TRUNC);
738 if (ret)
739 add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
740 return ret;
742 #else
743 static inline int try_force_unload(unsigned int flags)
745 return 0;
747 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
749 struct stopref
751 struct module *mod;
752 int flags;
753 int *forced;
756 /* Whole machine is stopped with interrupts off when this runs. */
757 static int __try_stop_module(void *_sref)
759 struct stopref *sref = _sref;
761 /* If it's not unused, quit unless we're forcing. */
762 if (module_refcount(sref->mod) != 0) {
763 if (!(*sref->forced = try_force_unload(sref->flags)))
764 return -EWOULDBLOCK;
767 /* Mark it as dying. */
768 sref->mod->state = MODULE_STATE_GOING;
769 return 0;
772 static int try_stop_module(struct module *mod, int flags, int *forced)
774 if (flags & O_NONBLOCK) {
775 struct stopref sref = { mod, flags, forced };
777 return stop_machine(__try_stop_module, &sref, NULL);
778 } else {
779 /* We don't need to stop the machine for this. */
780 mod->state = MODULE_STATE_GOING;
781 synchronize_sched();
782 return 0;
786 unsigned long module_refcount(struct module *mod)
788 unsigned long incs = 0, decs = 0;
789 int cpu;
791 for_each_possible_cpu(cpu)
792 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
794 * ensure the incs are added up after the decs.
795 * module_put ensures incs are visible before decs with smp_wmb.
797 * This 2-count scheme avoids the situation where the refcount
798 * for CPU0 is read, then CPU0 increments the module refcount,
799 * then CPU1 drops that refcount, then the refcount for CPU1 is
800 * read. We would record a decrement but not its corresponding
801 * increment so we would see a low count (disaster).
803 * Rare situation? But module_refcount can be preempted, and we
804 * might be tallying up 4096+ CPUs. So it is not impossible.
806 smp_rmb();
807 for_each_possible_cpu(cpu)
808 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
809 return incs - decs;
811 EXPORT_SYMBOL(module_refcount);
813 /* This exists whether we can unload or not */
814 static void free_module(struct module *mod);
816 static void wait_for_zero_refcount(struct module *mod)
818 /* Since we might sleep for some time, release the mutex first */
819 mutex_unlock(&module_mutex);
820 for (;;) {
821 pr_debug("Looking at refcount...\n");
822 set_current_state(TASK_UNINTERRUPTIBLE);
823 if (module_refcount(mod) == 0)
824 break;
825 schedule();
827 current->state = TASK_RUNNING;
828 mutex_lock(&module_mutex);
831 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
832 unsigned int, flags)
834 struct module *mod;
835 char name[MODULE_NAME_LEN];
836 int ret, forced = 0;
838 if (!capable(CAP_SYS_MODULE) || modules_disabled)
839 return -EPERM;
841 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
842 return -EFAULT;
843 name[MODULE_NAME_LEN-1] = '\0';
845 if (mutex_lock_interruptible(&module_mutex) != 0)
846 return -EINTR;
848 mod = find_module(name);
849 if (!mod) {
850 ret = -ENOENT;
851 goto out;
854 if (!list_empty(&mod->source_list)) {
855 /* Other modules depend on us: get rid of them first. */
856 ret = -EWOULDBLOCK;
857 goto out;
860 /* Doing init or already dying? */
861 if (mod->state != MODULE_STATE_LIVE) {
862 /* FIXME: if (force), slam module count and wake up
863 waiter --RR */
864 pr_debug("%s already dying\n", mod->name);
865 ret = -EBUSY;
866 goto out;
869 /* If it has an init func, it must have an exit func to unload */
870 if (mod->init && !mod->exit) {
871 forced = try_force_unload(flags);
872 if (!forced) {
873 /* This module can't be removed */
874 ret = -EBUSY;
875 goto out;
879 /* Set this up before setting mod->state */
880 mod->waiter = current;
882 /* Stop the machine so refcounts can't move and disable module. */
883 ret = try_stop_module(mod, flags, &forced);
884 if (ret != 0)
885 goto out;
887 /* Never wait if forced. */
888 if (!forced && module_refcount(mod) != 0)
889 wait_for_zero_refcount(mod);
891 mutex_unlock(&module_mutex);
892 /* Final destruction now no one is using it. */
893 if (mod->exit != NULL)
894 mod->exit();
895 blocking_notifier_call_chain(&module_notify_list,
896 MODULE_STATE_GOING, mod);
897 async_synchronize_full();
899 /* Store the name of the last unloaded module for diagnostic purposes */
900 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
902 free_module(mod);
903 return 0;
904 out:
905 mutex_unlock(&module_mutex);
906 return ret;
909 static inline void print_unload_info(struct seq_file *m, struct module *mod)
911 struct module_use *use;
912 int printed_something = 0;
914 seq_printf(m, " %lu ", module_refcount(mod));
916 /* Always include a trailing , so userspace can differentiate
917 between this and the old multi-field proc format. */
918 list_for_each_entry(use, &mod->source_list, source_list) {
919 printed_something = 1;
920 seq_printf(m, "%s,", use->source->name);
923 if (mod->init != NULL && mod->exit == NULL) {
924 printed_something = 1;
925 seq_printf(m, "[permanent],");
928 if (!printed_something)
929 seq_printf(m, "-");
932 void __symbol_put(const char *symbol)
934 struct module *owner;
936 preempt_disable();
937 if (!find_symbol(symbol, &owner, NULL, true, false))
938 BUG();
939 module_put(owner);
940 preempt_enable();
942 EXPORT_SYMBOL(__symbol_put);
944 /* Note this assumes addr is a function, which it currently always is. */
945 void symbol_put_addr(void *addr)
947 struct module *modaddr;
948 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
950 if (core_kernel_text(a))
951 return;
953 /* module_text_address is safe here: we're supposed to have reference
954 * to module from symbol_get, so it can't go away. */
955 modaddr = __module_text_address(a);
956 BUG_ON(!modaddr);
957 module_put(modaddr);
959 EXPORT_SYMBOL_GPL(symbol_put_addr);
961 static ssize_t show_refcnt(struct module_attribute *mattr,
962 struct module_kobject *mk, char *buffer)
964 return sprintf(buffer, "%lu\n", module_refcount(mk->mod));
967 static struct module_attribute modinfo_refcnt =
968 __ATTR(refcnt, 0444, show_refcnt, NULL);
970 void __module_get(struct module *module)
972 if (module) {
973 preempt_disable();
974 __this_cpu_inc(module->refptr->incs);
975 trace_module_get(module, _RET_IP_);
976 preempt_enable();
979 EXPORT_SYMBOL(__module_get);
981 bool try_module_get(struct module *module)
983 bool ret = true;
985 if (module) {
986 preempt_disable();
988 if (likely(module_is_live(module))) {
989 __this_cpu_inc(module->refptr->incs);
990 trace_module_get(module, _RET_IP_);
991 } else
992 ret = false;
994 preempt_enable();
996 return ret;
998 EXPORT_SYMBOL(try_module_get);
1000 void module_put(struct module *module)
1002 if (module) {
1003 preempt_disable();
1004 smp_wmb(); /* see comment in module_refcount */
1005 __this_cpu_inc(module->refptr->decs);
1007 trace_module_put(module, _RET_IP_);
1008 /* Maybe they're waiting for us to drop reference? */
1009 if (unlikely(!module_is_live(module)))
1010 wake_up_process(module->waiter);
1011 preempt_enable();
1014 EXPORT_SYMBOL(module_put);
1016 #else /* !CONFIG_MODULE_UNLOAD */
1017 static inline void print_unload_info(struct seq_file *m, struct module *mod)
1019 /* We don't know the usage count, or what modules are using. */
1020 seq_printf(m, " - -");
1023 static inline void module_unload_free(struct module *mod)
1027 int ref_module(struct module *a, struct module *b)
1029 return strong_try_module_get(b);
1031 EXPORT_SYMBOL_GPL(ref_module);
1033 static inline int module_unload_init(struct module *mod)
1035 return 0;
1037 #endif /* CONFIG_MODULE_UNLOAD */
1039 static size_t module_flags_taint(struct module *mod, char *buf)
1041 size_t l = 0;
1043 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
1044 buf[l++] = 'P';
1045 if (mod->taints & (1 << TAINT_OOT_MODULE))
1046 buf[l++] = 'O';
1047 if (mod->taints & (1 << TAINT_FORCED_MODULE))
1048 buf[l++] = 'F';
1049 if (mod->taints & (1 << TAINT_CRAP))
1050 buf[l++] = 'C';
1052 * TAINT_FORCED_RMMOD: could be added.
1053 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
1054 * apply to modules.
1056 return l;
1059 static ssize_t show_initstate(struct module_attribute *mattr,
1060 struct module_kobject *mk, char *buffer)
1062 const char *state = "unknown";
1064 switch (mk->mod->state) {
1065 case MODULE_STATE_LIVE:
1066 state = "live";
1067 break;
1068 case MODULE_STATE_COMING:
1069 state = "coming";
1070 break;
1071 case MODULE_STATE_GOING:
1072 state = "going";
1073 break;
1074 default:
1075 BUG();
1077 return sprintf(buffer, "%s\n", state);
1080 static struct module_attribute modinfo_initstate =
1081 __ATTR(initstate, 0444, show_initstate, NULL);
1083 static ssize_t store_uevent(struct module_attribute *mattr,
1084 struct module_kobject *mk,
1085 const char *buffer, size_t count)
1087 enum kobject_action action;
1089 if (kobject_action_type(buffer, count, &action) == 0)
1090 kobject_uevent(&mk->kobj, action);
1091 return count;
1094 struct module_attribute module_uevent =
1095 __ATTR(uevent, 0200, NULL, store_uevent);
1097 static ssize_t show_coresize(struct module_attribute *mattr,
1098 struct module_kobject *mk, char *buffer)
1100 return sprintf(buffer, "%u\n", mk->mod->core_size);
1103 static struct module_attribute modinfo_coresize =
1104 __ATTR(coresize, 0444, show_coresize, NULL);
1106 static ssize_t show_initsize(struct module_attribute *mattr,
1107 struct module_kobject *mk, char *buffer)
1109 return sprintf(buffer, "%u\n", mk->mod->init_size);
1112 static struct module_attribute modinfo_initsize =
1113 __ATTR(initsize, 0444, show_initsize, NULL);
1115 static ssize_t show_taint(struct module_attribute *mattr,
1116 struct module_kobject *mk, char *buffer)
1118 size_t l;
1120 l = module_flags_taint(mk->mod, buffer);
1121 buffer[l++] = '\n';
1122 return l;
1125 static struct module_attribute modinfo_taint =
1126 __ATTR(taint, 0444, show_taint, NULL);
1128 static struct module_attribute *modinfo_attrs[] = {
1129 &module_uevent,
1130 &modinfo_version,
1131 &modinfo_srcversion,
1132 &modinfo_initstate,
1133 &modinfo_coresize,
1134 &modinfo_initsize,
1135 &modinfo_taint,
1136 #ifdef CONFIG_MODULE_UNLOAD
1137 &modinfo_refcnt,
1138 #endif
1139 NULL,
1142 static const char vermagic[] = VERMAGIC_STRING;
1144 static int try_to_force_load(struct module *mod, const char *reason)
1146 #ifdef CONFIG_MODULE_FORCE_LOAD
1147 if (!test_taint(TAINT_FORCED_MODULE))
1148 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
1149 mod->name, reason);
1150 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
1151 return 0;
1152 #else
1153 return -ENOEXEC;
1154 #endif
1157 #ifdef CONFIG_MODVERSIONS
1158 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
1159 static unsigned long maybe_relocated(unsigned long crc,
1160 const struct module *crc_owner)
1162 #ifdef ARCH_RELOCATES_KCRCTAB
1163 if (crc_owner == NULL)
1164 return crc - (unsigned long)reloc_start;
1165 #endif
1166 return crc;
1169 static int check_version(Elf_Shdr *sechdrs,
1170 unsigned int versindex,
1171 const char *symname,
1172 struct module *mod,
1173 const unsigned long *crc,
1174 const struct module *crc_owner)
1176 unsigned int i, num_versions;
1177 struct modversion_info *versions;
1179 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1180 if (!crc)
1181 return 1;
1183 /* No versions at all? modprobe --force does this. */
1184 if (versindex == 0)
1185 return try_to_force_load(mod, symname) == 0;
1187 versions = (void *) sechdrs[versindex].sh_addr;
1188 num_versions = sechdrs[versindex].sh_size
1189 / sizeof(struct modversion_info);
1191 for (i = 0; i < num_versions; i++) {
1192 if (strcmp(versions[i].name, symname) != 0)
1193 continue;
1195 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
1196 return 1;
1197 pr_debug("Found checksum %lX vs module %lX\n",
1198 maybe_relocated(*crc, crc_owner), versions[i].crc);
1199 goto bad_version;
1202 printk(KERN_WARNING "%s: no symbol version for %s\n",
1203 mod->name, symname);
1204 return 0;
1206 bad_version:
1207 printk("%s: disagrees about version of symbol %s\n",
1208 mod->name, symname);
1209 return 0;
1212 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1213 unsigned int versindex,
1214 struct module *mod)
1216 const unsigned long *crc;
1218 /* Since this should be found in kernel (which can't be removed),
1219 * no locking is necessary. */
1220 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
1221 &crc, true, false))
1222 BUG();
1223 return check_version(sechdrs, versindex,
1224 VMLINUX_SYMBOL_STR(module_layout), mod, crc,
1225 NULL);
1228 /* First part is kernel version, which we ignore if module has crcs. */
1229 static inline int same_magic(const char *amagic, const char *bmagic,
1230 bool has_crcs)
1232 if (has_crcs) {
1233 amagic += strcspn(amagic, " ");
1234 bmagic += strcspn(bmagic, " ");
1236 return strcmp(amagic, bmagic) == 0;
1238 #else
1239 static inline int check_version(Elf_Shdr *sechdrs,
1240 unsigned int versindex,
1241 const char *symname,
1242 struct module *mod,
1243 const unsigned long *crc,
1244 const struct module *crc_owner)
1246 return 1;
1249 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1250 unsigned int versindex,
1251 struct module *mod)
1253 return 1;
1256 static inline int same_magic(const char *amagic, const char *bmagic,
1257 bool has_crcs)
1259 return strcmp(amagic, bmagic) == 0;
1261 #endif /* CONFIG_MODVERSIONS */
1263 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1264 static const struct kernel_symbol *resolve_symbol(struct module *mod,
1265 const struct load_info *info,
1266 const char *name,
1267 char ownername[])
1269 struct module *owner;
1270 const struct kernel_symbol *sym;
1271 const unsigned long *crc;
1272 int err;
1274 mutex_lock(&module_mutex);
1275 sym = find_symbol(name, &owner, &crc,
1276 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1277 if (!sym)
1278 goto unlock;
1280 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1281 owner)) {
1282 sym = ERR_PTR(-EINVAL);
1283 goto getname;
1286 err = ref_module(mod, owner);
1287 if (err) {
1288 sym = ERR_PTR(err);
1289 goto getname;
1292 getname:
1293 /* We must make copy under the lock if we failed to get ref. */
1294 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1295 unlock:
1296 mutex_unlock(&module_mutex);
1297 return sym;
1300 static const struct kernel_symbol *
1301 resolve_symbol_wait(struct module *mod,
1302 const struct load_info *info,
1303 const char *name)
1305 const struct kernel_symbol *ksym;
1306 char owner[MODULE_NAME_LEN];
1308 if (wait_event_interruptible_timeout(module_wq,
1309 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1310 || PTR_ERR(ksym) != -EBUSY,
1311 30 * HZ) <= 0) {
1312 printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
1313 mod->name, owner);
1315 return ksym;
1319 * /sys/module/foo/sections stuff
1320 * J. Corbet <corbet@lwn.net>
1322 #ifdef CONFIG_SYSFS
1324 #ifdef CONFIG_KALLSYMS
1325 static inline bool sect_empty(const Elf_Shdr *sect)
1327 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1330 struct module_sect_attr
1332 struct module_attribute mattr;
1333 char *name;
1334 unsigned long address;
1337 struct module_sect_attrs
1339 struct attribute_group grp;
1340 unsigned int nsections;
1341 struct module_sect_attr attrs[0];
1344 static ssize_t module_sect_show(struct module_attribute *mattr,
1345 struct module_kobject *mk, char *buf)
1347 struct module_sect_attr *sattr =
1348 container_of(mattr, struct module_sect_attr, mattr);
1349 return sprintf(buf, "0x%pK\n", (void *)sattr->address);
1352 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1354 unsigned int section;
1356 for (section = 0; section < sect_attrs->nsections; section++)
1357 kfree(sect_attrs->attrs[section].name);
1358 kfree(sect_attrs);
1361 static void add_sect_attrs(struct module *mod, const struct load_info *info)
1363 unsigned int nloaded = 0, i, size[2];
1364 struct module_sect_attrs *sect_attrs;
1365 struct module_sect_attr *sattr;
1366 struct attribute **gattr;
1368 /* Count loaded sections and allocate structures */
1369 for (i = 0; i < info->hdr->e_shnum; i++)
1370 if (!sect_empty(&info->sechdrs[i]))
1371 nloaded++;
1372 size[0] = ALIGN(sizeof(*sect_attrs)
1373 + nloaded * sizeof(sect_attrs->attrs[0]),
1374 sizeof(sect_attrs->grp.attrs[0]));
1375 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1376 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1377 if (sect_attrs == NULL)
1378 return;
1380 /* Setup section attributes. */
1381 sect_attrs->grp.name = "sections";
1382 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1384 sect_attrs->nsections = 0;
1385 sattr = &sect_attrs->attrs[0];
1386 gattr = &sect_attrs->grp.attrs[0];
1387 for (i = 0; i < info->hdr->e_shnum; i++) {
1388 Elf_Shdr *sec = &info->sechdrs[i];
1389 if (sect_empty(sec))
1390 continue;
1391 sattr->address = sec->sh_addr;
1392 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1393 GFP_KERNEL);
1394 if (sattr->name == NULL)
1395 goto out;
1396 sect_attrs->nsections++;
1397 sysfs_attr_init(&sattr->mattr.attr);
1398 sattr->mattr.show = module_sect_show;
1399 sattr->mattr.store = NULL;
1400 sattr->mattr.attr.name = sattr->name;
1401 sattr->mattr.attr.mode = S_IRUGO;
1402 *(gattr++) = &(sattr++)->mattr.attr;
1404 *gattr = NULL;
1406 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1407 goto out;
1409 mod->sect_attrs = sect_attrs;
1410 return;
1411 out:
1412 free_sect_attrs(sect_attrs);
1415 static void remove_sect_attrs(struct module *mod)
1417 if (mod->sect_attrs) {
1418 sysfs_remove_group(&mod->mkobj.kobj,
1419 &mod->sect_attrs->grp);
1420 /* We are positive that no one is using any sect attrs
1421 * at this point. Deallocate immediately. */
1422 free_sect_attrs(mod->sect_attrs);
1423 mod->sect_attrs = NULL;
1428 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1431 struct module_notes_attrs {
1432 struct kobject *dir;
1433 unsigned int notes;
1434 struct bin_attribute attrs[0];
1437 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1438 struct bin_attribute *bin_attr,
1439 char *buf, loff_t pos, size_t count)
1442 * The caller checked the pos and count against our size.
1444 memcpy(buf, bin_attr->private + pos, count);
1445 return count;
1448 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1449 unsigned int i)
1451 if (notes_attrs->dir) {
1452 while (i-- > 0)
1453 sysfs_remove_bin_file(notes_attrs->dir,
1454 &notes_attrs->attrs[i]);
1455 kobject_put(notes_attrs->dir);
1457 kfree(notes_attrs);
1460 static void add_notes_attrs(struct module *mod, const struct load_info *info)
1462 unsigned int notes, loaded, i;
1463 struct module_notes_attrs *notes_attrs;
1464 struct bin_attribute *nattr;
1466 /* failed to create section attributes, so can't create notes */
1467 if (!mod->sect_attrs)
1468 return;
1470 /* Count notes sections and allocate structures. */
1471 notes = 0;
1472 for (i = 0; i < info->hdr->e_shnum; i++)
1473 if (!sect_empty(&info->sechdrs[i]) &&
1474 (info->sechdrs[i].sh_type == SHT_NOTE))
1475 ++notes;
1477 if (notes == 0)
1478 return;
1480 notes_attrs = kzalloc(sizeof(*notes_attrs)
1481 + notes * sizeof(notes_attrs->attrs[0]),
1482 GFP_KERNEL);
1483 if (notes_attrs == NULL)
1484 return;
1486 notes_attrs->notes = notes;
1487 nattr = &notes_attrs->attrs[0];
1488 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1489 if (sect_empty(&info->sechdrs[i]))
1490 continue;
1491 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1492 sysfs_bin_attr_init(nattr);
1493 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1494 nattr->attr.mode = S_IRUGO;
1495 nattr->size = info->sechdrs[i].sh_size;
1496 nattr->private = (void *) info->sechdrs[i].sh_addr;
1497 nattr->read = module_notes_read;
1498 ++nattr;
1500 ++loaded;
1503 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1504 if (!notes_attrs->dir)
1505 goto out;
1507 for (i = 0; i < notes; ++i)
1508 if (sysfs_create_bin_file(notes_attrs->dir,
1509 &notes_attrs->attrs[i]))
1510 goto out;
1512 mod->notes_attrs = notes_attrs;
1513 return;
1515 out:
1516 free_notes_attrs(notes_attrs, i);
1519 static void remove_notes_attrs(struct module *mod)
1521 if (mod->notes_attrs)
1522 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1525 #else
1527 static inline void add_sect_attrs(struct module *mod,
1528 const struct load_info *info)
1532 static inline void remove_sect_attrs(struct module *mod)
1536 static inline void add_notes_attrs(struct module *mod,
1537 const struct load_info *info)
1541 static inline void remove_notes_attrs(struct module *mod)
1544 #endif /* CONFIG_KALLSYMS */
1546 static void add_usage_links(struct module *mod)
1548 #ifdef CONFIG_MODULE_UNLOAD
1549 struct module_use *use;
1550 int nowarn;
1552 mutex_lock(&module_mutex);
1553 list_for_each_entry(use, &mod->target_list, target_list) {
1554 nowarn = sysfs_create_link(use->target->holders_dir,
1555 &mod->mkobj.kobj, mod->name);
1557 mutex_unlock(&module_mutex);
1558 #endif
1561 static void del_usage_links(struct module *mod)
1563 #ifdef CONFIG_MODULE_UNLOAD
1564 struct module_use *use;
1566 mutex_lock(&module_mutex);
1567 list_for_each_entry(use, &mod->target_list, target_list)
1568 sysfs_remove_link(use->target->holders_dir, mod->name);
1569 mutex_unlock(&module_mutex);
1570 #endif
1573 static int module_add_modinfo_attrs(struct module *mod)
1575 struct module_attribute *attr;
1576 struct module_attribute *temp_attr;
1577 int error = 0;
1578 int i;
1580 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1581 (ARRAY_SIZE(modinfo_attrs) + 1)),
1582 GFP_KERNEL);
1583 if (!mod->modinfo_attrs)
1584 return -ENOMEM;
1586 temp_attr = mod->modinfo_attrs;
1587 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1588 if (!attr->test ||
1589 (attr->test && attr->test(mod))) {
1590 memcpy(temp_attr, attr, sizeof(*temp_attr));
1591 sysfs_attr_init(&temp_attr->attr);
1592 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1593 ++temp_attr;
1596 return error;
1599 static void module_remove_modinfo_attrs(struct module *mod)
1601 struct module_attribute *attr;
1602 int i;
1604 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1605 /* pick a field to test for end of list */
1606 if (!attr->attr.name)
1607 break;
1608 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1609 if (attr->free)
1610 attr->free(mod);
1612 kfree(mod->modinfo_attrs);
1615 static void mod_kobject_put(struct module *mod)
1617 DECLARE_COMPLETION_ONSTACK(c);
1618 mod->mkobj.kobj_completion = &c;
1619 kobject_put(&mod->mkobj.kobj);
1620 wait_for_completion(&c);
1623 static int mod_sysfs_init(struct module *mod)
1625 int err;
1626 struct kobject *kobj;
1628 if (!module_sysfs_initialized) {
1629 printk(KERN_ERR "%s: module sysfs not initialized\n",
1630 mod->name);
1631 err = -EINVAL;
1632 goto out;
1635 kobj = kset_find_obj(module_kset, mod->name);
1636 if (kobj) {
1637 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1638 kobject_put(kobj);
1639 err = -EINVAL;
1640 goto out;
1643 mod->mkobj.mod = mod;
1645 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1646 mod->mkobj.kobj.kset = module_kset;
1647 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1648 "%s", mod->name);
1649 if (err)
1650 mod_kobject_put(mod);
1652 /* delay uevent until full sysfs population */
1653 out:
1654 return err;
1657 static int mod_sysfs_setup(struct module *mod,
1658 const struct load_info *info,
1659 struct kernel_param *kparam,
1660 unsigned int num_params)
1662 int err;
1664 err = mod_sysfs_init(mod);
1665 if (err)
1666 goto out;
1668 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1669 if (!mod->holders_dir) {
1670 err = -ENOMEM;
1671 goto out_unreg;
1674 err = module_param_sysfs_setup(mod, kparam, num_params);
1675 if (err)
1676 goto out_unreg_holders;
1678 err = module_add_modinfo_attrs(mod);
1679 if (err)
1680 goto out_unreg_param;
1682 add_usage_links(mod);
1683 add_sect_attrs(mod, info);
1684 add_notes_attrs(mod, info);
1686 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1687 return 0;
1689 out_unreg_param:
1690 module_param_sysfs_remove(mod);
1691 out_unreg_holders:
1692 kobject_put(mod->holders_dir);
1693 out_unreg:
1694 mod_kobject_put(mod);
1695 out:
1696 return err;
1699 static void mod_sysfs_fini(struct module *mod)
1701 remove_notes_attrs(mod);
1702 remove_sect_attrs(mod);
1703 mod_kobject_put(mod);
1706 #else /* !CONFIG_SYSFS */
1708 static int mod_sysfs_setup(struct module *mod,
1709 const struct load_info *info,
1710 struct kernel_param *kparam,
1711 unsigned int num_params)
1713 return 0;
1716 static void mod_sysfs_fini(struct module *mod)
1720 static void module_remove_modinfo_attrs(struct module *mod)
1724 static void del_usage_links(struct module *mod)
1728 #endif /* CONFIG_SYSFS */
1730 static void mod_sysfs_teardown(struct module *mod)
1732 del_usage_links(mod);
1733 module_remove_modinfo_attrs(mod);
1734 module_param_sysfs_remove(mod);
1735 kobject_put(mod->mkobj.drivers_dir);
1736 kobject_put(mod->holders_dir);
1737 mod_sysfs_fini(mod);
1741 * unlink the module with the whole machine is stopped with interrupts off
1742 * - this defends against kallsyms not taking locks
1744 static int __unlink_module(void *_mod)
1746 struct module *mod = _mod;
1747 list_del(&mod->list);
1748 module_bug_cleanup(mod);
1749 return 0;
1752 #ifdef CONFIG_DEBUG_SET_MODULE_RONX
1754 * LKM RO/NX protection: protect module's text/ro-data
1755 * from modification and any data from execution.
1757 void set_page_attributes(void *start, void *end, int (*set)(unsigned long start, int num_pages))
1759 unsigned long begin_pfn = PFN_DOWN((unsigned long)start);
1760 unsigned long end_pfn = PFN_DOWN((unsigned long)end);
1762 if (end_pfn > begin_pfn)
1763 set(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1766 static void set_section_ro_nx(void *base,
1767 unsigned long text_size,
1768 unsigned long ro_size,
1769 unsigned long total_size)
1771 /* begin and end PFNs of the current subsection */
1772 unsigned long begin_pfn;
1773 unsigned long end_pfn;
1776 * Set RO for module text and RO-data:
1777 * - Always protect first page.
1778 * - Do not protect last partial page.
1780 if (ro_size > 0)
1781 set_page_attributes(base, base + ro_size, set_memory_ro);
1784 * Set NX permissions for module data:
1785 * - Do not protect first partial page.
1786 * - Always protect last page.
1788 if (total_size > text_size) {
1789 begin_pfn = PFN_UP((unsigned long)base + text_size);
1790 end_pfn = PFN_UP((unsigned long)base + total_size);
1791 if (end_pfn > begin_pfn)
1792 set_memory_nx(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1796 static void unset_module_core_ro_nx(struct module *mod)
1798 set_page_attributes(mod->module_core + mod->core_text_size,
1799 mod->module_core + mod->core_size,
1800 set_memory_x);
1801 set_page_attributes(mod->module_core,
1802 mod->module_core + mod->core_ro_size,
1803 set_memory_rw);
1806 static void unset_module_init_ro_nx(struct module *mod)
1808 set_page_attributes(mod->module_init + mod->init_text_size,
1809 mod->module_init + mod->init_size,
1810 set_memory_x);
1811 set_page_attributes(mod->module_init,
1812 mod->module_init + mod->init_ro_size,
1813 set_memory_rw);
1816 /* Iterate through all modules and set each module's text as RW */
1817 void set_all_modules_text_rw(void)
1819 struct module *mod;
1821 mutex_lock(&module_mutex);
1822 list_for_each_entry_rcu(mod, &modules, list) {
1823 if (mod->state == MODULE_STATE_UNFORMED)
1824 continue;
1825 if ((mod->module_core) && (mod->core_text_size)) {
1826 set_page_attributes(mod->module_core,
1827 mod->module_core + mod->core_text_size,
1828 set_memory_rw);
1830 if ((mod->module_init) && (mod->init_text_size)) {
1831 set_page_attributes(mod->module_init,
1832 mod->module_init + mod->init_text_size,
1833 set_memory_rw);
1836 mutex_unlock(&module_mutex);
1839 /* Iterate through all modules and set each module's text as RO */
1840 void set_all_modules_text_ro(void)
1842 struct module *mod;
1844 mutex_lock(&module_mutex);
1845 list_for_each_entry_rcu(mod, &modules, list) {
1846 if (mod->state == MODULE_STATE_UNFORMED)
1847 continue;
1848 if ((mod->module_core) && (mod->core_text_size)) {
1849 set_page_attributes(mod->module_core,
1850 mod->module_core + mod->core_text_size,
1851 set_memory_ro);
1853 if ((mod->module_init) && (mod->init_text_size)) {
1854 set_page_attributes(mod->module_init,
1855 mod->module_init + mod->init_text_size,
1856 set_memory_ro);
1859 mutex_unlock(&module_mutex);
1861 #else
1862 static inline void set_section_ro_nx(void *base, unsigned long text_size, unsigned long ro_size, unsigned long total_size) { }
1863 static void unset_module_core_ro_nx(struct module *mod) { }
1864 static void unset_module_init_ro_nx(struct module *mod) { }
1865 #endif
1867 void __weak module_free(struct module *mod, void *module_region)
1869 vfree(module_region);
1872 void __weak module_arch_cleanup(struct module *mod)
1876 /* Free a module, remove from lists, etc. */
1877 static void free_module(struct module *mod)
1879 trace_module_free(mod);
1881 mod_sysfs_teardown(mod);
1883 /* We leave it in list to prevent duplicate loads, but make sure
1884 * that noone uses it while it's being deconstructed. */
1885 mod->state = MODULE_STATE_UNFORMED;
1887 /* Remove dynamic debug info */
1888 ddebug_remove_module(mod->name);
1890 /* Arch-specific cleanup. */
1891 module_arch_cleanup(mod);
1893 /* Module unload stuff */
1894 module_unload_free(mod);
1896 /* Free any allocated parameters. */
1897 destroy_params(mod->kp, mod->num_kp);
1899 /* Now we can delete it from the lists */
1900 mutex_lock(&module_mutex);
1901 stop_machine(__unlink_module, mod, NULL);
1902 mutex_unlock(&module_mutex);
1904 /* This may be NULL, but that's OK */
1905 unset_module_init_ro_nx(mod);
1906 module_free(mod, mod->module_init);
1907 kfree(mod->args);
1908 percpu_modfree(mod);
1910 /* Free lock-classes: */
1911 lockdep_free_key_range(mod->module_core, mod->core_size);
1913 /* Finally, free the core (containing the module structure) */
1914 unset_module_core_ro_nx(mod);
1915 module_free(mod, mod->module_core);
1917 #ifdef CONFIG_MPU
1918 update_protections(current->mm);
1919 #endif
1922 void *__symbol_get(const char *symbol)
1924 struct module *owner;
1925 const struct kernel_symbol *sym;
1927 preempt_disable();
1928 sym = find_symbol(symbol, &owner, NULL, true, true);
1929 if (sym && strong_try_module_get(owner))
1930 sym = NULL;
1931 preempt_enable();
1933 return sym ? (void *)sym->value : NULL;
1935 EXPORT_SYMBOL_GPL(__symbol_get);
1938 * Ensure that an exported symbol [global namespace] does not already exist
1939 * in the kernel or in some other module's exported symbol table.
1941 * You must hold the module_mutex.
1943 static int verify_export_symbols(struct module *mod)
1945 unsigned int i;
1946 struct module *owner;
1947 const struct kernel_symbol *s;
1948 struct {
1949 const struct kernel_symbol *sym;
1950 unsigned int num;
1951 } arr[] = {
1952 { mod->syms, mod->num_syms },
1953 { mod->gpl_syms, mod->num_gpl_syms },
1954 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1955 #ifdef CONFIG_UNUSED_SYMBOLS
1956 { mod->unused_syms, mod->num_unused_syms },
1957 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1958 #endif
1961 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1962 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1963 if (find_symbol(s->name, &owner, NULL, true, false)) {
1964 printk(KERN_ERR
1965 "%s: exports duplicate symbol %s"
1966 " (owned by %s)\n",
1967 mod->name, s->name, module_name(owner));
1968 return -ENOEXEC;
1972 return 0;
1975 /* Change all symbols so that st_value encodes the pointer directly. */
1976 static int simplify_symbols(struct module *mod, const struct load_info *info)
1978 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
1979 Elf_Sym *sym = (void *)symsec->sh_addr;
1980 unsigned long secbase;
1981 unsigned int i;
1982 int ret = 0;
1983 const struct kernel_symbol *ksym;
1985 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
1986 const char *name = info->strtab + sym[i].st_name;
1988 switch (sym[i].st_shndx) {
1989 case SHN_COMMON:
1990 /* We compiled with -fno-common. These are not
1991 supposed to happen. */
1992 pr_debug("Common symbol: %s\n", name);
1993 printk("%s: please compile with -fno-common\n",
1994 mod->name);
1995 ret = -ENOEXEC;
1996 break;
1998 case SHN_ABS:
1999 /* Don't need to do anything */
2000 pr_debug("Absolute symbol: 0x%08lx\n",
2001 (long)sym[i].st_value);
2002 break;
2004 case SHN_UNDEF:
2005 ksym = resolve_symbol_wait(mod, info, name);
2006 /* Ok if resolved. */
2007 if (ksym && !IS_ERR(ksym)) {
2008 sym[i].st_value = ksym->value;
2009 break;
2012 /* Ok if weak. */
2013 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
2014 break;
2016 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
2017 mod->name, name, PTR_ERR(ksym));
2018 ret = PTR_ERR(ksym) ?: -ENOENT;
2019 break;
2021 default:
2022 /* Divert to percpu allocation if a percpu var. */
2023 if (sym[i].st_shndx == info->index.pcpu)
2024 secbase = (unsigned long)mod_percpu(mod);
2025 else
2026 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
2027 sym[i].st_value += secbase;
2028 break;
2032 return ret;
2035 static int apply_relocations(struct module *mod, const struct load_info *info)
2037 unsigned int i;
2038 int err = 0;
2040 /* Now do relocations. */
2041 for (i = 1; i < info->hdr->e_shnum; i++) {
2042 unsigned int infosec = info->sechdrs[i].sh_info;
2044 /* Not a valid relocation section? */
2045 if (infosec >= info->hdr->e_shnum)
2046 continue;
2048 /* Don't bother with non-allocated sections */
2049 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
2050 continue;
2052 if (info->sechdrs[i].sh_type == SHT_REL)
2053 err = apply_relocate(info->sechdrs, info->strtab,
2054 info->index.sym, i, mod);
2055 else if (info->sechdrs[i].sh_type == SHT_RELA)
2056 err = apply_relocate_add(info->sechdrs, info->strtab,
2057 info->index.sym, i, mod);
2058 if (err < 0)
2059 break;
2061 return err;
2064 /* Additional bytes needed by arch in front of individual sections */
2065 unsigned int __weak arch_mod_section_prepend(struct module *mod,
2066 unsigned int section)
2068 /* default implementation just returns zero */
2069 return 0;
2072 /* Update size with this section: return offset. */
2073 static long get_offset(struct module *mod, unsigned int *size,
2074 Elf_Shdr *sechdr, unsigned int section)
2076 long ret;
2078 *size += arch_mod_section_prepend(mod, section);
2079 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2080 *size = ret + sechdr->sh_size;
2081 return ret;
2084 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2085 might -- code, read-only data, read-write data, small data. Tally
2086 sizes, and place the offsets into sh_entsize fields: high bit means it
2087 belongs in init. */
2088 static void layout_sections(struct module *mod, struct load_info *info)
2090 static unsigned long const masks[][2] = {
2091 /* NOTE: all executable code must be the first section
2092 * in this array; otherwise modify the text_size
2093 * finder in the two loops below */
2094 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2095 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
2096 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2097 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2099 unsigned int m, i;
2101 for (i = 0; i < info->hdr->e_shnum; i++)
2102 info->sechdrs[i].sh_entsize = ~0UL;
2104 pr_debug("Core section allocation order:\n");
2105 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2106 for (i = 0; i < info->hdr->e_shnum; ++i) {
2107 Elf_Shdr *s = &info->sechdrs[i];
2108 const char *sname = info->secstrings + s->sh_name;
2110 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2111 || (s->sh_flags & masks[m][1])
2112 || s->sh_entsize != ~0UL
2113 || strstarts(sname, ".init"))
2114 continue;
2115 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
2116 pr_debug("\t%s\n", sname);
2118 switch (m) {
2119 case 0: /* executable */
2120 mod->core_size = debug_align(mod->core_size);
2121 mod->core_text_size = mod->core_size;
2122 break;
2123 case 1: /* RO: text and ro-data */
2124 mod->core_size = debug_align(mod->core_size);
2125 mod->core_ro_size = mod->core_size;
2126 break;
2127 case 3: /* whole core */
2128 mod->core_size = debug_align(mod->core_size);
2129 break;
2133 pr_debug("Init section allocation order:\n");
2134 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2135 for (i = 0; i < info->hdr->e_shnum; ++i) {
2136 Elf_Shdr *s = &info->sechdrs[i];
2137 const char *sname = info->secstrings + s->sh_name;
2139 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2140 || (s->sh_flags & masks[m][1])
2141 || s->sh_entsize != ~0UL
2142 || !strstarts(sname, ".init"))
2143 continue;
2144 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
2145 | INIT_OFFSET_MASK);
2146 pr_debug("\t%s\n", sname);
2148 switch (m) {
2149 case 0: /* executable */
2150 mod->init_size = debug_align(mod->init_size);
2151 mod->init_text_size = mod->init_size;
2152 break;
2153 case 1: /* RO: text and ro-data */
2154 mod->init_size = debug_align(mod->init_size);
2155 mod->init_ro_size = mod->init_size;
2156 break;
2157 case 3: /* whole init */
2158 mod->init_size = debug_align(mod->init_size);
2159 break;
2164 static void set_license(struct module *mod, const char *license)
2166 if (!license)
2167 license = "unspecified";
2169 if (!license_is_gpl_compatible(license)) {
2170 if (!test_taint(TAINT_PROPRIETARY_MODULE))
2171 printk(KERN_WARNING "%s: module license '%s' taints "
2172 "kernel.\n", mod->name, license);
2173 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2174 LOCKDEP_NOW_UNRELIABLE);
2178 /* Parse tag=value strings from .modinfo section */
2179 static char *next_string(char *string, unsigned long *secsize)
2181 /* Skip non-zero chars */
2182 while (string[0]) {
2183 string++;
2184 if ((*secsize)-- <= 1)
2185 return NULL;
2188 /* Skip any zero padding. */
2189 while (!string[0]) {
2190 string++;
2191 if ((*secsize)-- <= 1)
2192 return NULL;
2194 return string;
2197 static char *get_modinfo(struct load_info *info, const char *tag)
2199 char *p;
2200 unsigned int taglen = strlen(tag);
2201 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2202 unsigned long size = infosec->sh_size;
2204 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
2205 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2206 return p + taglen + 1;
2208 return NULL;
2211 static void setup_modinfo(struct module *mod, struct load_info *info)
2213 struct module_attribute *attr;
2214 int i;
2216 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2217 if (attr->setup)
2218 attr->setup(mod, get_modinfo(info, attr->attr.name));
2222 static void free_modinfo(struct module *mod)
2224 struct module_attribute *attr;
2225 int i;
2227 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2228 if (attr->free)
2229 attr->free(mod);
2233 #ifdef CONFIG_KALLSYMS
2235 /* lookup symbol in given range of kernel_symbols */
2236 static const struct kernel_symbol *lookup_symbol(const char *name,
2237 const struct kernel_symbol *start,
2238 const struct kernel_symbol *stop)
2240 return bsearch(name, start, stop - start,
2241 sizeof(struct kernel_symbol), cmp_name);
2244 static int is_exported(const char *name, unsigned long value,
2245 const struct module *mod)
2247 const struct kernel_symbol *ks;
2248 if (!mod)
2249 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
2250 else
2251 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
2252 return ks != NULL && ks->value == value;
2255 /* As per nm */
2256 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
2258 const Elf_Shdr *sechdrs = info->sechdrs;
2260 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2261 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2262 return 'v';
2263 else
2264 return 'w';
2266 if (sym->st_shndx == SHN_UNDEF)
2267 return 'U';
2268 if (sym->st_shndx == SHN_ABS)
2269 return 'a';
2270 if (sym->st_shndx >= SHN_LORESERVE)
2271 return '?';
2272 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2273 return 't';
2274 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2275 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2276 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2277 return 'r';
2278 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2279 return 'g';
2280 else
2281 return 'd';
2283 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2284 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2285 return 's';
2286 else
2287 return 'b';
2289 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2290 ".debug")) {
2291 return 'n';
2293 return '?';
2296 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
2297 unsigned int shnum)
2299 const Elf_Shdr *sec;
2301 if (src->st_shndx == SHN_UNDEF
2302 || src->st_shndx >= shnum
2303 || !src->st_name)
2304 return false;
2306 sec = sechdrs + src->st_shndx;
2307 if (!(sec->sh_flags & SHF_ALLOC)
2308 #ifndef CONFIG_KALLSYMS_ALL
2309 || !(sec->sh_flags & SHF_EXECINSTR)
2310 #endif
2311 || (sec->sh_entsize & INIT_OFFSET_MASK))
2312 return false;
2314 return true;
2318 * We only allocate and copy the strings needed by the parts of symtab
2319 * we keep. This is simple, but has the effect of making multiple
2320 * copies of duplicates. We could be more sophisticated, see
2321 * linux-kernel thread starting with
2322 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2324 static void layout_symtab(struct module *mod, struct load_info *info)
2326 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2327 Elf_Shdr *strsect = info->sechdrs + info->index.str;
2328 const Elf_Sym *src;
2329 unsigned int i, nsrc, ndst, strtab_size = 0;
2331 /* Put symbol section at end of init part of module. */
2332 symsect->sh_flags |= SHF_ALLOC;
2333 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
2334 info->index.sym) | INIT_OFFSET_MASK;
2335 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
2337 src = (void *)info->hdr + symsect->sh_offset;
2338 nsrc = symsect->sh_size / sizeof(*src);
2340 /* Compute total space required for the core symbols' strtab. */
2341 for (ndst = i = 0; i < nsrc; i++) {
2342 if (i == 0 ||
2343 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2344 strtab_size += strlen(&info->strtab[src[i].st_name])+1;
2345 ndst++;
2349 /* Append room for core symbols at end of core part. */
2350 info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
2351 info->stroffs = mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym);
2352 mod->core_size += strtab_size;
2354 /* Put string table section at end of init part of module. */
2355 strsect->sh_flags |= SHF_ALLOC;
2356 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
2357 info->index.str) | INIT_OFFSET_MASK;
2358 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
2361 static void add_kallsyms(struct module *mod, const struct load_info *info)
2363 unsigned int i, ndst;
2364 const Elf_Sym *src;
2365 Elf_Sym *dst;
2366 char *s;
2367 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2369 mod->symtab = (void *)symsec->sh_addr;
2370 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2371 /* Make sure we get permanent strtab: don't use info->strtab. */
2372 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2374 /* Set types up while we still have access to sections. */
2375 for (i = 0; i < mod->num_symtab; i++)
2376 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
2378 mod->core_symtab = dst = mod->module_core + info->symoffs;
2379 mod->core_strtab = s = mod->module_core + info->stroffs;
2380 src = mod->symtab;
2381 for (ndst = i = 0; i < mod->num_symtab; i++) {
2382 if (i == 0 ||
2383 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2384 dst[ndst] = src[i];
2385 dst[ndst++].st_name = s - mod->core_strtab;
2386 s += strlcpy(s, &mod->strtab[src[i].st_name],
2387 KSYM_NAME_LEN) + 1;
2390 mod->core_num_syms = ndst;
2392 #else
2393 static inline void layout_symtab(struct module *mod, struct load_info *info)
2397 static void add_kallsyms(struct module *mod, const struct load_info *info)
2400 #endif /* CONFIG_KALLSYMS */
2402 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2404 if (!debug)
2405 return;
2406 #ifdef CONFIG_DYNAMIC_DEBUG
2407 if (ddebug_add_module(debug, num, debug->modname))
2408 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2409 debug->modname);
2410 #endif
2413 static void dynamic_debug_remove(struct _ddebug *debug)
2415 if (debug)
2416 ddebug_remove_module(debug->modname);
2419 void * __weak module_alloc(unsigned long size)
2421 return vmalloc_exec(size);
2424 static void *module_alloc_update_bounds(unsigned long size)
2426 void *ret = module_alloc(size);
2428 if (ret) {
2429 mutex_lock(&module_mutex);
2430 /* Update module bounds. */
2431 if ((unsigned long)ret < module_addr_min)
2432 module_addr_min = (unsigned long)ret;
2433 if ((unsigned long)ret + size > module_addr_max)
2434 module_addr_max = (unsigned long)ret + size;
2435 mutex_unlock(&module_mutex);
2437 return ret;
2440 #ifdef CONFIG_DEBUG_KMEMLEAK
2441 static void kmemleak_load_module(const struct module *mod,
2442 const struct load_info *info)
2444 unsigned int i;
2446 /* only scan the sections containing data */
2447 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2449 for (i = 1; i < info->hdr->e_shnum; i++) {
2450 /* Scan all writable sections that's not executable */
2451 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
2452 !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
2453 (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
2454 continue;
2456 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2457 info->sechdrs[i].sh_size, GFP_KERNEL);
2460 #else
2461 static inline void kmemleak_load_module(const struct module *mod,
2462 const struct load_info *info)
2465 #endif
2467 #ifdef CONFIG_MODULE_SIG
2468 static int module_sig_check(struct load_info *info)
2470 int err = -ENOKEY;
2471 const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2472 const void *mod = info->hdr;
2474 if (info->len > markerlen &&
2475 memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
2476 /* We truncate the module to discard the signature */
2477 info->len -= markerlen;
2478 err = mod_verify_sig(mod, &info->len);
2481 if (!err) {
2482 info->sig_ok = true;
2483 return 0;
2486 /* Not having a signature is only an error if we're strict. */
2487 if (err < 0 && fips_enabled)
2488 panic("Module verification failed with error %d in FIPS mode\n",
2489 err);
2490 if (err == -ENOKEY && !sig_enforce)
2491 err = 0;
2493 return err;
2495 #else /* !CONFIG_MODULE_SIG */
2496 static int module_sig_check(struct load_info *info)
2498 return 0;
2500 #endif /* !CONFIG_MODULE_SIG */
2502 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2503 static int elf_header_check(struct load_info *info)
2505 if (info->len < sizeof(*(info->hdr)))
2506 return -ENOEXEC;
2508 if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2509 || info->hdr->e_type != ET_REL
2510 || !elf_check_arch(info->hdr)
2511 || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2512 return -ENOEXEC;
2514 if (info->hdr->e_shoff >= info->len
2515 || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2516 info->len - info->hdr->e_shoff))
2517 return -ENOEXEC;
2519 return 0;
2522 /* Sets info->hdr and info->len. */
2523 static int copy_module_from_user(const void __user *umod, unsigned long len,
2524 struct load_info *info)
2526 int err;
2528 info->len = len;
2529 if (info->len < sizeof(*(info->hdr)))
2530 return -ENOEXEC;
2532 err = security_kernel_module_from_file(NULL);
2533 if (err)
2534 return err;
2536 /* Suck in entire file: we'll want most of it. */
2537 info->hdr = vmalloc(info->len);
2538 if (!info->hdr)
2539 return -ENOMEM;
2541 if (copy_from_user(info->hdr, umod, info->len) != 0) {
2542 vfree(info->hdr);
2543 return -EFAULT;
2546 return 0;
2549 /* Sets info->hdr and info->len. */
2550 static int copy_module_from_fd(int fd, struct load_info *info)
2552 struct fd f = fdget(fd);
2553 int err;
2554 struct kstat stat;
2555 loff_t pos;
2556 ssize_t bytes = 0;
2558 if (!f.file)
2559 return -ENOEXEC;
2561 err = security_kernel_module_from_file(f.file);
2562 if (err)
2563 goto out;
2565 err = vfs_getattr(&f.file->f_path, &stat);
2566 if (err)
2567 goto out;
2569 if (stat.size > INT_MAX) {
2570 err = -EFBIG;
2571 goto out;
2574 /* Don't hand 0 to vmalloc, it whines. */
2575 if (stat.size == 0) {
2576 err = -EINVAL;
2577 goto out;
2580 info->hdr = vmalloc(stat.size);
2581 if (!info->hdr) {
2582 err = -ENOMEM;
2583 goto out;
2586 pos = 0;
2587 while (pos < stat.size) {
2588 bytes = kernel_read(f.file, pos, (char *)(info->hdr) + pos,
2589 stat.size - pos);
2590 if (bytes < 0) {
2591 vfree(info->hdr);
2592 err = bytes;
2593 goto out;
2595 if (bytes == 0)
2596 break;
2597 pos += bytes;
2599 info->len = pos;
2601 out:
2602 fdput(f);
2603 return err;
2606 static void free_copy(struct load_info *info)
2608 vfree(info->hdr);
2611 static int rewrite_section_headers(struct load_info *info, int flags)
2613 unsigned int i;
2615 /* This should always be true, but let's be sure. */
2616 info->sechdrs[0].sh_addr = 0;
2618 for (i = 1; i < info->hdr->e_shnum; i++) {
2619 Elf_Shdr *shdr = &info->sechdrs[i];
2620 if (shdr->sh_type != SHT_NOBITS
2621 && info->len < shdr->sh_offset + shdr->sh_size) {
2622 printk(KERN_ERR "Module len %lu truncated\n",
2623 info->len);
2624 return -ENOEXEC;
2627 /* Mark all sections sh_addr with their address in the
2628 temporary image. */
2629 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2631 #ifndef CONFIG_MODULE_UNLOAD
2632 /* Don't load .exit sections */
2633 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2634 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2635 #endif
2638 /* Track but don't keep modinfo and version sections. */
2639 if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
2640 info->index.vers = 0; /* Pretend no __versions section! */
2641 else
2642 info->index.vers = find_sec(info, "__versions");
2643 info->index.info = find_sec(info, ".modinfo");
2644 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2645 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2646 return 0;
2650 * Set up our basic convenience variables (pointers to section headers,
2651 * search for module section index etc), and do some basic section
2652 * verification.
2654 * Return the temporary module pointer (we'll replace it with the final
2655 * one when we move the module sections around).
2657 static struct module *setup_load_info(struct load_info *info, int flags)
2659 unsigned int i;
2660 int err;
2661 struct module *mod;
2663 /* Set up the convenience variables */
2664 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2665 info->secstrings = (void *)info->hdr
2666 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2668 err = rewrite_section_headers(info, flags);
2669 if (err)
2670 return ERR_PTR(err);
2672 /* Find internal symbols and strings. */
2673 for (i = 1; i < info->hdr->e_shnum; i++) {
2674 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2675 info->index.sym = i;
2676 info->index.str = info->sechdrs[i].sh_link;
2677 info->strtab = (char *)info->hdr
2678 + info->sechdrs[info->index.str].sh_offset;
2679 break;
2683 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
2684 if (!info->index.mod) {
2685 printk(KERN_WARNING "No module found in object\n");
2686 return ERR_PTR(-ENOEXEC);
2688 /* This is temporary: point mod into copy of data. */
2689 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2691 if (info->index.sym == 0) {
2692 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2693 mod->name);
2694 return ERR_PTR(-ENOEXEC);
2697 info->index.pcpu = find_pcpusec(info);
2699 /* Check module struct version now, before we try to use module. */
2700 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2701 return ERR_PTR(-ENOEXEC);
2703 return mod;
2706 static int check_modinfo(struct module *mod, struct load_info *info, int flags)
2708 const char *modmagic = get_modinfo(info, "vermagic");
2709 int err;
2711 if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2712 modmagic = NULL;
2714 /* This is allowed: modprobe --force will invalidate it. */
2715 if (!modmagic) {
2716 err = try_to_force_load(mod, "bad vermagic");
2717 if (err)
2718 return err;
2719 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2720 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2721 mod->name, modmagic, vermagic);
2722 return -ENOEXEC;
2725 if (!get_modinfo(info, "intree"))
2726 add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
2728 if (get_modinfo(info, "staging")) {
2729 add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
2730 printk(KERN_WARNING "%s: module is from the staging directory,"
2731 " the quality is unknown, you have been warned.\n",
2732 mod->name);
2735 /* Set up license info based on the info section */
2736 set_license(mod, get_modinfo(info, "license"));
2738 return 0;
2741 static void find_module_sections(struct module *mod, struct load_info *info)
2743 mod->kp = section_objs(info, "__param",
2744 sizeof(*mod->kp), &mod->num_kp);
2745 mod->syms = section_objs(info, "__ksymtab",
2746 sizeof(*mod->syms), &mod->num_syms);
2747 mod->crcs = section_addr(info, "__kcrctab");
2748 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2749 sizeof(*mod->gpl_syms),
2750 &mod->num_gpl_syms);
2751 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2752 mod->gpl_future_syms = section_objs(info,
2753 "__ksymtab_gpl_future",
2754 sizeof(*mod->gpl_future_syms),
2755 &mod->num_gpl_future_syms);
2756 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
2758 #ifdef CONFIG_UNUSED_SYMBOLS
2759 mod->unused_syms = section_objs(info, "__ksymtab_unused",
2760 sizeof(*mod->unused_syms),
2761 &mod->num_unused_syms);
2762 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2763 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
2764 sizeof(*mod->unused_gpl_syms),
2765 &mod->num_unused_gpl_syms);
2766 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
2767 #endif
2768 #ifdef CONFIG_CONSTRUCTORS
2769 mod->ctors = section_objs(info, ".ctors",
2770 sizeof(*mod->ctors), &mod->num_ctors);
2771 #endif
2773 #ifdef CONFIG_TRACEPOINTS
2774 mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2775 sizeof(*mod->tracepoints_ptrs),
2776 &mod->num_tracepoints);
2777 #endif
2778 #ifdef HAVE_JUMP_LABEL
2779 mod->jump_entries = section_objs(info, "__jump_table",
2780 sizeof(*mod->jump_entries),
2781 &mod->num_jump_entries);
2782 #endif
2783 #ifdef CONFIG_EVENT_TRACING
2784 mod->trace_events = section_objs(info, "_ftrace_events",
2785 sizeof(*mod->trace_events),
2786 &mod->num_trace_events);
2787 #endif
2788 #ifdef CONFIG_TRACING
2789 mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2790 sizeof(*mod->trace_bprintk_fmt_start),
2791 &mod->num_trace_bprintk_fmt);
2792 #endif
2793 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2794 /* sechdrs[0].sh_size is always zero */
2795 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
2796 sizeof(*mod->ftrace_callsites),
2797 &mod->num_ftrace_callsites);
2798 #endif
2800 mod->extable = section_objs(info, "__ex_table",
2801 sizeof(*mod->extable), &mod->num_exentries);
2803 if (section_addr(info, "__obsparm"))
2804 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2805 mod->name);
2807 info->debug = section_objs(info, "__verbose",
2808 sizeof(*info->debug), &info->num_debug);
2811 static int move_module(struct module *mod, struct load_info *info)
2813 int i;
2814 void *ptr;
2816 /* Do the allocs. */
2817 ptr = module_alloc_update_bounds(mod->core_size);
2819 * The pointer to this block is stored in the module structure
2820 * which is inside the block. Just mark it as not being a
2821 * leak.
2823 kmemleak_not_leak(ptr);
2824 if (!ptr)
2825 return -ENOMEM;
2827 memset(ptr, 0, mod->core_size);
2828 mod->module_core = ptr;
2830 if (mod->init_size) {
2831 ptr = module_alloc_update_bounds(mod->init_size);
2833 * The pointer to this block is stored in the module structure
2834 * which is inside the block. This block doesn't need to be
2835 * scanned as it contains data and code that will be freed
2836 * after the module is initialized.
2838 kmemleak_ignore(ptr);
2839 if (!ptr) {
2840 module_free(mod, mod->module_core);
2841 return -ENOMEM;
2843 memset(ptr, 0, mod->init_size);
2844 mod->module_init = ptr;
2845 } else
2846 mod->module_init = NULL;
2848 /* Transfer each section which specifies SHF_ALLOC */
2849 pr_debug("final section addresses:\n");
2850 for (i = 0; i < info->hdr->e_shnum; i++) {
2851 void *dest;
2852 Elf_Shdr *shdr = &info->sechdrs[i];
2854 if (!(shdr->sh_flags & SHF_ALLOC))
2855 continue;
2857 if (shdr->sh_entsize & INIT_OFFSET_MASK)
2858 dest = mod->module_init
2859 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
2860 else
2861 dest = mod->module_core + shdr->sh_entsize;
2863 if (shdr->sh_type != SHT_NOBITS)
2864 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2865 /* Update sh_addr to point to copy in image. */
2866 shdr->sh_addr = (unsigned long)dest;
2867 pr_debug("\t0x%lx %s\n",
2868 (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
2871 return 0;
2874 static int check_module_license_and_versions(struct module *mod)
2877 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2878 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2879 * using GPL-only symbols it needs.
2881 if (strcmp(mod->name, "ndiswrapper") == 0)
2882 add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
2884 /* driverloader was caught wrongly pretending to be under GPL */
2885 if (strcmp(mod->name, "driverloader") == 0)
2886 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2887 LOCKDEP_NOW_UNRELIABLE);
2889 /* lve claims to be GPL but upstream won't provide source */
2890 if (strcmp(mod->name, "lve") == 0)
2891 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2892 LOCKDEP_NOW_UNRELIABLE);
2894 #ifdef CONFIG_MODVERSIONS
2895 if ((mod->num_syms && !mod->crcs)
2896 || (mod->num_gpl_syms && !mod->gpl_crcs)
2897 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2898 #ifdef CONFIG_UNUSED_SYMBOLS
2899 || (mod->num_unused_syms && !mod->unused_crcs)
2900 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2901 #endif
2903 return try_to_force_load(mod,
2904 "no versions for exported symbols");
2906 #endif
2907 return 0;
2910 static void flush_module_icache(const struct module *mod)
2912 mm_segment_t old_fs;
2914 /* flush the icache in correct context */
2915 old_fs = get_fs();
2916 set_fs(KERNEL_DS);
2919 * Flush the instruction cache, since we've played with text.
2920 * Do it before processing of module parameters, so the module
2921 * can provide parameter accessor functions of its own.
2923 if (mod->module_init)
2924 flush_icache_range((unsigned long)mod->module_init,
2925 (unsigned long)mod->module_init
2926 + mod->init_size);
2927 flush_icache_range((unsigned long)mod->module_core,
2928 (unsigned long)mod->module_core + mod->core_size);
2930 set_fs(old_fs);
2933 int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
2934 Elf_Shdr *sechdrs,
2935 char *secstrings,
2936 struct module *mod)
2938 return 0;
2941 static struct module *layout_and_allocate(struct load_info *info, int flags)
2943 /* Module within temporary copy. */
2944 struct module *mod;
2945 int err;
2947 mod = setup_load_info(info, flags);
2948 if (IS_ERR(mod))
2949 return mod;
2951 err = check_modinfo(mod, info, flags);
2952 if (err)
2953 return ERR_PTR(err);
2955 /* Allow arches to frob section contents and sizes. */
2956 err = module_frob_arch_sections(info->hdr, info->sechdrs,
2957 info->secstrings, mod);
2958 if (err < 0)
2959 return ERR_PTR(err);
2961 /* We will do a special allocation for per-cpu sections later. */
2962 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
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);
2970 /* Allocate and move to the final place */
2971 err = move_module(mod, info);
2972 if (err)
2973 return ERR_PTR(err);
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;
2981 /* mod is no longer valid after this! */
2982 static void module_deallocate(struct module *mod, struct load_info *info)
2984 percpu_modfree(mod);
2985 module_free(mod, mod->module_init);
2986 module_free(mod, mod->module_core);
2989 int __weak module_finalize(const Elf_Ehdr *hdr,
2990 const Elf_Shdr *sechdrs,
2991 struct module *me)
2993 return 0;
2996 static int post_relocation(struct module *mod, const struct load_info *info)
2998 /* Sort exception table now relocations are done. */
2999 sort_extable(mod->extable, mod->extable + mod->num_exentries);
3001 /* Copy relocated percpu area over. */
3002 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
3003 info->sechdrs[info->index.pcpu].sh_size);
3005 /* Setup kallsyms-specific fields. */
3006 add_kallsyms(mod, info);
3008 /* Arch-specific module finalizing. */
3009 return module_finalize(info->hdr, info->sechdrs, mod);
3012 /* Is this module of this name done loading? No locks held. */
3013 static bool finished_loading(const char *name)
3015 struct module *mod;
3016 bool ret;
3018 mutex_lock(&module_mutex);
3019 mod = find_module_all(name, strlen(name), true);
3020 ret = !mod || mod->state == MODULE_STATE_LIVE
3021 || mod->state == MODULE_STATE_GOING;
3022 mutex_unlock(&module_mutex);
3024 return ret;
3027 /* Call module constructors. */
3028 static void do_mod_ctors(struct module *mod)
3030 #ifdef CONFIG_CONSTRUCTORS
3031 unsigned long i;
3033 for (i = 0; i < mod->num_ctors; i++)
3034 mod->ctors[i]();
3035 #endif
3038 /* This is where the real work happens */
3039 static int do_init_module(struct module *mod)
3041 int ret = 0;
3044 * We want to find out whether @mod uses async during init. Clear
3045 * PF_USED_ASYNC. async_schedule*() will set it.
3047 current->flags &= ~PF_USED_ASYNC;
3049 blocking_notifier_call_chain(&module_notify_list,
3050 MODULE_STATE_COMING, mod);
3052 /* Set RO and NX regions for core */
3053 set_section_ro_nx(mod->module_core,
3054 mod->core_text_size,
3055 mod->core_ro_size,
3056 mod->core_size);
3058 /* Set RO and NX regions for init */
3059 set_section_ro_nx(mod->module_init,
3060 mod->init_text_size,
3061 mod->init_ro_size,
3062 mod->init_size);
3064 do_mod_ctors(mod);
3065 /* Start the module */
3066 if (mod->init != NULL)
3067 ret = do_one_initcall(mod->init);
3068 if (ret < 0) {
3069 /* Init routine failed: abort. Try to protect us from
3070 buggy refcounters. */
3071 mod->state = MODULE_STATE_GOING;
3072 synchronize_sched();
3073 module_put(mod);
3074 blocking_notifier_call_chain(&module_notify_list,
3075 MODULE_STATE_GOING, mod);
3076 free_module(mod);
3077 wake_up_all(&module_wq);
3078 return ret;
3080 if (ret > 0) {
3081 printk(KERN_WARNING
3082 "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
3083 "%s: loading module anyway...\n",
3084 __func__, mod->name, ret,
3085 __func__);
3086 dump_stack();
3089 /* Now it's a first class citizen! */
3090 mod->state = MODULE_STATE_LIVE;
3091 blocking_notifier_call_chain(&module_notify_list,
3092 MODULE_STATE_LIVE, mod);
3095 * We need to finish all async code before the module init sequence
3096 * is done. This has potential to deadlock. For example, a newly
3097 * detected block device can trigger request_module() of the
3098 * default iosched from async probing task. Once userland helper
3099 * reaches here, async_synchronize_full() will wait on the async
3100 * task waiting on request_module() and deadlock.
3102 * This deadlock is avoided by perfomring async_synchronize_full()
3103 * iff module init queued any async jobs. This isn't a full
3104 * solution as it will deadlock the same if module loading from
3105 * async jobs nests more than once; however, due to the various
3106 * constraints, this hack seems to be the best option for now.
3107 * Please refer to the following thread for details.
3109 * http://thread.gmane.org/gmane.linux.kernel/1420814
3111 if (current->flags & PF_USED_ASYNC)
3112 async_synchronize_full();
3114 mutex_lock(&module_mutex);
3115 /* Drop initial reference. */
3116 module_put(mod);
3117 trim_init_extable(mod);
3118 #ifdef CONFIG_KALLSYMS
3119 mod->num_symtab = mod->core_num_syms;
3120 mod->symtab = mod->core_symtab;
3121 mod->strtab = mod->core_strtab;
3122 #endif
3123 unset_module_init_ro_nx(mod);
3124 module_free(mod, mod->module_init);
3125 mod->module_init = NULL;
3126 mod->init_size = 0;
3127 mod->init_ro_size = 0;
3128 mod->init_text_size = 0;
3129 mutex_unlock(&module_mutex);
3130 wake_up_all(&module_wq);
3132 return 0;
3135 static int may_init_module(void)
3137 if (!capable(CAP_SYS_MODULE) || modules_disabled)
3138 return -EPERM;
3140 return 0;
3144 * We try to place it in the list now to make sure it's unique before
3145 * we dedicate too many resources. In particular, temporary percpu
3146 * memory exhaustion.
3148 static int add_unformed_module(struct module *mod)
3150 int err;
3151 struct module *old;
3153 mod->state = MODULE_STATE_UNFORMED;
3155 again:
3156 mutex_lock(&module_mutex);
3157 old = find_module_all(mod->name, strlen(mod->name), true);
3158 if (old != NULL) {
3159 if (old->state == MODULE_STATE_COMING
3160 || old->state == MODULE_STATE_UNFORMED) {
3161 /* Wait in case it fails to load. */
3162 mutex_unlock(&module_mutex);
3163 err = wait_event_interruptible(module_wq,
3164 finished_loading(mod->name));
3165 if (err)
3166 goto out_unlocked;
3167 goto again;
3169 err = -EEXIST;
3170 goto out;
3172 list_add_rcu(&mod->list, &modules);
3173 err = 0;
3175 out:
3176 mutex_unlock(&module_mutex);
3177 out_unlocked:
3178 return err;
3181 static int complete_formation(struct module *mod, struct load_info *info)
3183 int err;
3185 mutex_lock(&module_mutex);
3187 /* Find duplicate symbols (must be called under lock). */
3188 err = verify_export_symbols(mod);
3189 if (err < 0)
3190 goto out;
3192 /* This relies on module_mutex for list integrity. */
3193 module_bug_finalize(info->hdr, info->sechdrs, mod);
3195 /* Mark state as coming so strong_try_module_get() ignores us,
3196 * but kallsyms etc. can see us. */
3197 mod->state = MODULE_STATE_COMING;
3199 out:
3200 mutex_unlock(&module_mutex);
3201 return err;
3204 static int unknown_module_param_cb(char *param, char *val, const char *modname)
3206 /* Check for magic 'dyndbg' arg */
3207 int ret = ddebug_dyndbg_module_param_cb(param, val, modname);
3208 if (ret != 0) {
3209 printk(KERN_WARNING "%s: unknown parameter '%s' ignored\n",
3210 modname, param);
3212 return 0;
3215 /* Allocate and load the module: note that size of section 0 is always
3216 zero, and we rely on this for optional sections. */
3217 static int load_module(struct load_info *info, const char __user *uargs,
3218 int flags)
3220 struct module *mod;
3221 long err;
3223 err = module_sig_check(info);
3224 if (err)
3225 goto free_copy;
3227 err = elf_header_check(info);
3228 if (err)
3229 goto free_copy;
3231 /* Figure out module layout, and allocate all the memory. */
3232 mod = layout_and_allocate(info, flags);
3233 if (IS_ERR(mod)) {
3234 err = PTR_ERR(mod);
3235 goto free_copy;
3238 /* Reserve our place in the list. */
3239 err = add_unformed_module(mod);
3240 if (err)
3241 goto free_module;
3243 #ifdef CONFIG_MODULE_SIG
3244 mod->sig_ok = info->sig_ok;
3245 if (!mod->sig_ok) {
3246 printk_once(KERN_NOTICE
3247 "%s: module verification failed: signature and/or"
3248 " required key missing - tainting kernel\n",
3249 mod->name);
3250 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_STILL_OK);
3252 #endif
3254 /* To avoid stressing percpu allocator, do this once we're unique. */
3255 err = percpu_modalloc(mod, info);
3256 if (err)
3257 goto unlink_mod;
3259 /* Now module is in final location, initialize linked lists, etc. */
3260 err = module_unload_init(mod);
3261 if (err)
3262 goto unlink_mod;
3264 /* Now we've got everything in the final locations, we can
3265 * find optional sections. */
3266 find_module_sections(mod, info);
3268 err = check_module_license_and_versions(mod);
3269 if (err)
3270 goto free_unload;
3272 /* Set up MODINFO_ATTR fields */
3273 setup_modinfo(mod, info);
3275 /* Fix up syms, so that st_value is a pointer to location. */
3276 err = simplify_symbols(mod, info);
3277 if (err < 0)
3278 goto free_modinfo;
3280 err = apply_relocations(mod, info);
3281 if (err < 0)
3282 goto free_modinfo;
3284 err = post_relocation(mod, info);
3285 if (err < 0)
3286 goto free_modinfo;
3288 flush_module_icache(mod);
3290 /* Now copy in args */
3291 mod->args = strndup_user(uargs, ~0UL >> 1);
3292 if (IS_ERR(mod->args)) {
3293 err = PTR_ERR(mod->args);
3294 goto free_arch_cleanup;
3297 dynamic_debug_setup(info->debug, info->num_debug);
3299 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3300 ftrace_module_init(mod);
3302 /* Finally it's fully formed, ready to start executing. */
3303 err = complete_formation(mod, info);
3304 if (err)
3305 goto ddebug_cleanup;
3307 /* Module is ready to execute: parsing args may do that. */
3308 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
3309 -32768, 32767, unknown_module_param_cb);
3310 if (err < 0)
3311 goto bug_cleanup;
3313 /* Link in to syfs. */
3314 err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3315 if (err < 0)
3316 goto bug_cleanup;
3318 /* Get rid of temporary copy. */
3319 free_copy(info);
3321 /* Done! */
3322 trace_module_load(mod);
3324 return do_init_module(mod);
3326 bug_cleanup:
3327 /* module_bug_cleanup needs module_mutex protection */
3328 mutex_lock(&module_mutex);
3329 module_bug_cleanup(mod);
3330 mutex_unlock(&module_mutex);
3331 ddebug_cleanup:
3332 dynamic_debug_remove(info->debug);
3333 synchronize_sched();
3334 kfree(mod->args);
3335 free_arch_cleanup:
3336 module_arch_cleanup(mod);
3337 free_modinfo:
3338 free_modinfo(mod);
3339 free_unload:
3340 module_unload_free(mod);
3341 unlink_mod:
3342 mutex_lock(&module_mutex);
3343 /* Unlink carefully: kallsyms could be walking list. */
3344 list_del_rcu(&mod->list);
3345 wake_up_all(&module_wq);
3346 mutex_unlock(&module_mutex);
3347 free_module:
3348 module_deallocate(mod, info);
3349 free_copy:
3350 free_copy(info);
3351 return err;
3354 SYSCALL_DEFINE3(init_module, void __user *, umod,
3355 unsigned long, len, const char __user *, uargs)
3357 int err;
3358 struct load_info info = { };
3360 err = may_init_module();
3361 if (err)
3362 return err;
3364 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3365 umod, len, uargs);
3367 err = copy_module_from_user(umod, len, &info);
3368 if (err)
3369 return err;
3371 return load_module(&info, uargs, 0);
3374 SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3376 int err;
3377 struct load_info info = { };
3379 err = may_init_module();
3380 if (err)
3381 return err;
3383 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3385 if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3386 |MODULE_INIT_IGNORE_VERMAGIC))
3387 return -EINVAL;
3389 err = copy_module_from_fd(fd, &info);
3390 if (err)
3391 return err;
3393 return load_module(&info, uargs, flags);
3396 static inline int within(unsigned long addr, void *start, unsigned long size)
3398 return ((void *)addr >= start && (void *)addr < start + size);
3401 #ifdef CONFIG_KALLSYMS
3403 * This ignores the intensely annoying "mapping symbols" found
3404 * in ARM ELF files: $a, $t and $d.
3406 static inline int is_arm_mapping_symbol(const char *str)
3408 return str[0] == '$' && strchr("atd", str[1])
3409 && (str[2] == '\0' || str[2] == '.');
3412 static const char *get_ksymbol(struct module *mod,
3413 unsigned long addr,
3414 unsigned long *size,
3415 unsigned long *offset)
3417 unsigned int i, best = 0;
3418 unsigned long nextval;
3420 /* At worse, next value is at end of module */
3421 if (within_module_init(addr, mod))
3422 nextval = (unsigned long)mod->module_init+mod->init_text_size;
3423 else
3424 nextval = (unsigned long)mod->module_core+mod->core_text_size;
3426 /* Scan for closest preceding symbol, and next symbol. (ELF
3427 starts real symbols at 1). */
3428 for (i = 1; i < mod->num_symtab; i++) {
3429 if (mod->symtab[i].st_shndx == SHN_UNDEF)
3430 continue;
3432 /* We ignore unnamed symbols: they're uninformative
3433 * and inserted at a whim. */
3434 if (mod->symtab[i].st_value <= addr
3435 && mod->symtab[i].st_value > mod->symtab[best].st_value
3436 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3437 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3438 best = i;
3439 if (mod->symtab[i].st_value > addr
3440 && mod->symtab[i].st_value < nextval
3441 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3442 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3443 nextval = mod->symtab[i].st_value;
3446 if (!best)
3447 return NULL;
3449 if (size)
3450 *size = nextval - mod->symtab[best].st_value;
3451 if (offset)
3452 *offset = addr - mod->symtab[best].st_value;
3453 return mod->strtab + mod->symtab[best].st_name;
3456 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3457 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3458 const char *module_address_lookup(unsigned long addr,
3459 unsigned long *size,
3460 unsigned long *offset,
3461 char **modname,
3462 char *namebuf)
3464 struct module *mod;
3465 const char *ret = NULL;
3467 preempt_disable();
3468 list_for_each_entry_rcu(mod, &modules, list) {
3469 if (mod->state == MODULE_STATE_UNFORMED)
3470 continue;
3471 if (within_module_init(addr, mod) ||
3472 within_module_core(addr, mod)) {
3473 if (modname)
3474 *modname = mod->name;
3475 ret = get_ksymbol(mod, addr, size, offset);
3476 break;
3479 /* Make a copy in here where it's safe */
3480 if (ret) {
3481 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
3482 ret = namebuf;
3484 preempt_enable();
3485 return ret;
3488 int lookup_module_symbol_name(unsigned long addr, char *symname)
3490 struct module *mod;
3492 preempt_disable();
3493 list_for_each_entry_rcu(mod, &modules, list) {
3494 if (mod->state == MODULE_STATE_UNFORMED)
3495 continue;
3496 if (within_module_init(addr, mod) ||
3497 within_module_core(addr, mod)) {
3498 const char *sym;
3500 sym = get_ksymbol(mod, addr, NULL, NULL);
3501 if (!sym)
3502 goto out;
3503 strlcpy(symname, sym, KSYM_NAME_LEN);
3504 preempt_enable();
3505 return 0;
3508 out:
3509 preempt_enable();
3510 return -ERANGE;
3513 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
3514 unsigned long *offset, char *modname, char *name)
3516 struct module *mod;
3518 preempt_disable();
3519 list_for_each_entry_rcu(mod, &modules, list) {
3520 if (mod->state == MODULE_STATE_UNFORMED)
3521 continue;
3522 if (within_module_init(addr, mod) ||
3523 within_module_core(addr, mod)) {
3524 const char *sym;
3526 sym = get_ksymbol(mod, addr, size, offset);
3527 if (!sym)
3528 goto out;
3529 if (modname)
3530 strlcpy(modname, mod->name, MODULE_NAME_LEN);
3531 if (name)
3532 strlcpy(name, sym, KSYM_NAME_LEN);
3533 preempt_enable();
3534 return 0;
3537 out:
3538 preempt_enable();
3539 return -ERANGE;
3542 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
3543 char *name, char *module_name, int *exported)
3545 struct module *mod;
3547 preempt_disable();
3548 list_for_each_entry_rcu(mod, &modules, list) {
3549 if (mod->state == MODULE_STATE_UNFORMED)
3550 continue;
3551 if (symnum < mod->num_symtab) {
3552 *value = mod->symtab[symnum].st_value;
3553 *type = mod->symtab[symnum].st_info;
3554 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
3555 KSYM_NAME_LEN);
3556 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
3557 *exported = is_exported(name, *value, mod);
3558 preempt_enable();
3559 return 0;
3561 symnum -= mod->num_symtab;
3563 preempt_enable();
3564 return -ERANGE;
3567 static unsigned long mod_find_symname(struct module *mod, const char *name)
3569 unsigned int i;
3571 for (i = 0; i < mod->num_symtab; i++)
3572 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
3573 mod->symtab[i].st_info != 'U')
3574 return mod->symtab[i].st_value;
3575 return 0;
3578 /* Look for this name: can be of form module:name. */
3579 unsigned long module_kallsyms_lookup_name(const char *name)
3581 struct module *mod;
3582 char *colon;
3583 unsigned long ret = 0;
3585 /* Don't lock: we're in enough trouble already. */
3586 preempt_disable();
3587 if ((colon = strchr(name, ':')) != NULL) {
3588 if ((mod = find_module_all(name, colon - name, false)) != NULL)
3589 ret = mod_find_symname(mod, colon+1);
3590 } else {
3591 list_for_each_entry_rcu(mod, &modules, list) {
3592 if (mod->state == MODULE_STATE_UNFORMED)
3593 continue;
3594 if ((ret = mod_find_symname(mod, name)) != 0)
3595 break;
3598 preempt_enable();
3599 return ret;
3602 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3603 struct module *, unsigned long),
3604 void *data)
3606 struct module *mod;
3607 unsigned int i;
3608 int ret;
3610 list_for_each_entry(mod, &modules, list) {
3611 if (mod->state == MODULE_STATE_UNFORMED)
3612 continue;
3613 for (i = 0; i < mod->num_symtab; i++) {
3614 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
3615 mod, mod->symtab[i].st_value);
3616 if (ret != 0)
3617 return ret;
3620 return 0;
3622 #endif /* CONFIG_KALLSYMS */
3624 static char *module_flags(struct module *mod, char *buf)
3626 int bx = 0;
3628 BUG_ON(mod->state == MODULE_STATE_UNFORMED);
3629 if (mod->taints ||
3630 mod->state == MODULE_STATE_GOING ||
3631 mod->state == MODULE_STATE_COMING) {
3632 buf[bx++] = '(';
3633 bx += module_flags_taint(mod, buf + bx);
3634 /* Show a - for module-is-being-unloaded */
3635 if (mod->state == MODULE_STATE_GOING)
3636 buf[bx++] = '-';
3637 /* Show a + for module-is-being-loaded */
3638 if (mod->state == MODULE_STATE_COMING)
3639 buf[bx++] = '+';
3640 buf[bx++] = ')';
3642 buf[bx] = '\0';
3644 return buf;
3647 #ifdef CONFIG_PROC_FS
3648 /* Called by the /proc file system to return a list of modules. */
3649 static void *m_start(struct seq_file *m, loff_t *pos)
3651 mutex_lock(&module_mutex);
3652 return seq_list_start(&modules, *pos);
3655 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3657 return seq_list_next(p, &modules, pos);
3660 static void m_stop(struct seq_file *m, void *p)
3662 mutex_unlock(&module_mutex);
3665 static int m_show(struct seq_file *m, void *p)
3667 struct module *mod = list_entry(p, struct module, list);
3668 char buf[8];
3670 /* We always ignore unformed modules. */
3671 if (mod->state == MODULE_STATE_UNFORMED)
3672 return 0;
3674 seq_printf(m, "%s %u",
3675 mod->name, mod->init_size + mod->core_size);
3676 print_unload_info(m, mod);
3678 /* Informative for users. */
3679 seq_printf(m, " %s",
3680 mod->state == MODULE_STATE_GOING ? "Unloading":
3681 mod->state == MODULE_STATE_COMING ? "Loading":
3682 "Live");
3683 /* Used by oprofile and other similar tools. */
3684 seq_printf(m, " 0x%pK", mod->module_core);
3686 /* Taints info */
3687 if (mod->taints)
3688 seq_printf(m, " %s", module_flags(mod, buf));
3690 seq_printf(m, "\n");
3691 return 0;
3694 /* Format: modulename size refcount deps address
3696 Where refcount is a number or -, and deps is a comma-separated list
3697 of depends or -.
3699 static const struct seq_operations modules_op = {
3700 .start = m_start,
3701 .next = m_next,
3702 .stop = m_stop,
3703 .show = m_show
3706 static int modules_open(struct inode *inode, struct file *file)
3708 return seq_open(file, &modules_op);
3711 static const struct file_operations proc_modules_operations = {
3712 .open = modules_open,
3713 .read = seq_read,
3714 .llseek = seq_lseek,
3715 .release = seq_release,
3718 static int __init proc_modules_init(void)
3720 proc_create("modules", 0, NULL, &proc_modules_operations);
3721 return 0;
3723 module_init(proc_modules_init);
3724 #endif
3726 /* Given an address, look for it in the module exception tables. */
3727 const struct exception_table_entry *search_module_extables(unsigned long addr)
3729 const struct exception_table_entry *e = NULL;
3730 struct module *mod;
3732 preempt_disable();
3733 list_for_each_entry_rcu(mod, &modules, list) {
3734 if (mod->state == MODULE_STATE_UNFORMED)
3735 continue;
3736 if (mod->num_exentries == 0)
3737 continue;
3739 e = search_extable(mod->extable,
3740 mod->extable + mod->num_exentries - 1,
3741 addr);
3742 if (e)
3743 break;
3745 preempt_enable();
3747 /* Now, if we found one, we are running inside it now, hence
3748 we cannot unload the module, hence no refcnt needed. */
3749 return e;
3753 * is_module_address - is this address inside a module?
3754 * @addr: the address to check.
3756 * See is_module_text_address() if you simply want to see if the address
3757 * is code (not data).
3759 bool is_module_address(unsigned long addr)
3761 bool ret;
3763 preempt_disable();
3764 ret = __module_address(addr) != NULL;
3765 preempt_enable();
3767 return ret;
3771 * __module_address - get the module which contains an address.
3772 * @addr: the address.
3774 * Must be called with preempt disabled or module mutex held so that
3775 * module doesn't get freed during this.
3777 struct module *__module_address(unsigned long addr)
3779 struct module *mod;
3781 if (addr < module_addr_min || addr > module_addr_max)
3782 return NULL;
3784 list_for_each_entry_rcu(mod, &modules, list) {
3785 if (mod->state == MODULE_STATE_UNFORMED)
3786 continue;
3787 if (within_module_core(addr, mod)
3788 || within_module_init(addr, mod))
3789 return mod;
3791 return NULL;
3793 EXPORT_SYMBOL_GPL(__module_address);
3796 * is_module_text_address - is this address inside module code?
3797 * @addr: the address to check.
3799 * See is_module_address() if you simply want to see if the address is
3800 * anywhere in a module. See kernel_text_address() for testing if an
3801 * address corresponds to kernel or module code.
3803 bool is_module_text_address(unsigned long addr)
3805 bool ret;
3807 preempt_disable();
3808 ret = __module_text_address(addr) != NULL;
3809 preempt_enable();
3811 return ret;
3815 * __module_text_address - get the module whose code contains an address.
3816 * @addr: the address.
3818 * Must be called with preempt disabled or module mutex held so that
3819 * module doesn't get freed during this.
3821 struct module *__module_text_address(unsigned long addr)
3823 struct module *mod = __module_address(addr);
3824 if (mod) {
3825 /* Make sure it's within the text section. */
3826 if (!within(addr, mod->module_init, mod->init_text_size)
3827 && !within(addr, mod->module_core, mod->core_text_size))
3828 mod = NULL;
3830 return mod;
3832 EXPORT_SYMBOL_GPL(__module_text_address);
3834 /* Don't grab lock, we're oopsing. */
3835 void print_modules(void)
3837 struct module *mod;
3838 char buf[8];
3840 printk(KERN_DEFAULT "Modules linked in:");
3841 /* Most callers should already have preempt disabled, but make sure */
3842 preempt_disable();
3843 list_for_each_entry_rcu(mod, &modules, list) {
3844 if (mod->state == MODULE_STATE_UNFORMED)
3845 continue;
3846 printk(" %s%s", mod->name, module_flags(mod, buf));
3848 preempt_enable();
3849 if (last_unloaded_module[0])
3850 printk(" [last unloaded: %s]", last_unloaded_module);
3851 printk("\n");
3854 #ifdef CONFIG_MODVERSIONS
3855 /* Generate the signature for all relevant module structures here.
3856 * If these change, we don't want to try to parse the module. */
3857 void module_layout(struct module *mod,
3858 struct modversion_info *ver,
3859 struct kernel_param *kp,
3860 struct kernel_symbol *ks,
3861 struct tracepoint * const *tp)
3864 EXPORT_SYMBOL(module_layout);
3865 #endif