ARM: at91: at91sam9: use SoC detection infrastructure
[linux/fpc-iii.git] / kernel / module.c
blobb34813f725e970fa79b97e625fab6c568543aaf8
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/device.h>
46 #include <linux/string.h>
47 #include <linux/mutex.h>
48 #include <linux/rculist.h>
49 #include <asm/uaccess.h>
50 #include <asm/cacheflush.h>
51 #include <asm/mmu_context.h>
52 #include <linux/license.h>
53 #include <asm/sections.h>
54 #include <linux/tracepoint.h>
55 #include <linux/ftrace.h>
56 #include <linux/async.h>
57 #include <linux/percpu.h>
58 #include <linux/kmemleak.h>
59 #include <linux/kasan.h>
60 #include <linux/jump_label.h>
61 #include <linux/pfn.h>
62 #include <linux/bsearch.h>
63 #include <uapi/linux/module.h>
64 #include "module-internal.h"
66 #define CREATE_TRACE_POINTS
67 #include <trace/events/module.h>
69 #ifndef ARCH_SHF_SMALL
70 #define ARCH_SHF_SMALL 0
71 #endif
74 * Modules' sections will be aligned on page boundaries
75 * to ensure complete separation of code and data, but
76 * only when CONFIG_DEBUG_SET_MODULE_RONX=y
78 #ifdef CONFIG_DEBUG_SET_MODULE_RONX
79 # define debug_align(X) ALIGN(X, PAGE_SIZE)
80 #else
81 # define debug_align(X) (X)
82 #endif
85 * Given BASE and SIZE this macro calculates the number of pages the
86 * memory regions occupies
88 #define MOD_NUMBER_OF_PAGES(BASE, SIZE) (((SIZE) > 0) ? \
89 (PFN_DOWN((unsigned long)(BASE) + (SIZE) - 1) - \
90 PFN_DOWN((unsigned long)BASE) + 1) \
91 : (0UL))
93 /* If this is set, the section belongs in the init part of the module */
94 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
97 * Mutex protects:
98 * 1) List of modules (also safely readable with preempt_disable),
99 * 2) module_use links,
100 * 3) module_addr_min/module_addr_max.
101 * (delete and add uses RCU list operations). */
102 DEFINE_MUTEX(module_mutex);
103 EXPORT_SYMBOL_GPL(module_mutex);
104 static LIST_HEAD(modules);
105 #ifdef CONFIG_KGDB_KDB
106 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
107 #endif /* CONFIG_KGDB_KDB */
109 #ifdef CONFIG_MODULE_SIG
110 #ifdef CONFIG_MODULE_SIG_FORCE
111 static bool sig_enforce = true;
112 #else
113 static bool sig_enforce = false;
115 static int param_set_bool_enable_only(const char *val,
116 const struct kernel_param *kp)
118 int err;
119 bool test;
120 struct kernel_param dummy_kp = *kp;
122 dummy_kp.arg = &test;
124 err = param_set_bool(val, &dummy_kp);
125 if (err)
126 return err;
128 /* Don't let them unset it once it's set! */
129 if (!test && sig_enforce)
130 return -EROFS;
132 if (test)
133 sig_enforce = true;
134 return 0;
137 static const struct kernel_param_ops param_ops_bool_enable_only = {
138 .flags = KERNEL_PARAM_OPS_FL_NOARG,
139 .set = param_set_bool_enable_only,
140 .get = param_get_bool,
142 #define param_check_bool_enable_only param_check_bool
144 module_param(sig_enforce, bool_enable_only, 0644);
145 #endif /* !CONFIG_MODULE_SIG_FORCE */
146 #endif /* CONFIG_MODULE_SIG */
148 /* Block module loading/unloading? */
149 int modules_disabled = 0;
150 core_param(nomodule, modules_disabled, bint, 0);
152 /* Waiting for a module to finish initializing? */
153 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
155 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
157 /* Bounds of module allocation, for speeding __module_address.
158 * Protected by module_mutex. */
159 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
161 int register_module_notifier(struct notifier_block *nb)
163 return blocking_notifier_chain_register(&module_notify_list, nb);
165 EXPORT_SYMBOL(register_module_notifier);
167 int unregister_module_notifier(struct notifier_block *nb)
169 return blocking_notifier_chain_unregister(&module_notify_list, nb);
171 EXPORT_SYMBOL(unregister_module_notifier);
173 struct load_info {
174 Elf_Ehdr *hdr;
175 unsigned long len;
176 Elf_Shdr *sechdrs;
177 char *secstrings, *strtab;
178 unsigned long symoffs, stroffs;
179 struct _ddebug *debug;
180 unsigned int num_debug;
181 bool sig_ok;
182 struct {
183 unsigned int sym, str, mod, vers, info, pcpu;
184 } index;
187 /* We require a truly strong try_module_get(): 0 means failure due to
188 ongoing or failed initialization etc. */
189 static inline int strong_try_module_get(struct module *mod)
191 BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
192 if (mod && mod->state == MODULE_STATE_COMING)
193 return -EBUSY;
194 if (try_module_get(mod))
195 return 0;
196 else
197 return -ENOENT;
200 static inline void add_taint_module(struct module *mod, unsigned flag,
201 enum lockdep_ok lockdep_ok)
203 add_taint(flag, lockdep_ok);
204 mod->taints |= (1U << flag);
208 * A thread that wants to hold a reference to a module only while it
209 * is running can call this to safely exit. nfsd and lockd use this.
211 void __module_put_and_exit(struct module *mod, long code)
213 module_put(mod);
214 do_exit(code);
216 EXPORT_SYMBOL(__module_put_and_exit);
218 /* Find a module section: 0 means not found. */
219 static unsigned int find_sec(const struct load_info *info, const char *name)
221 unsigned int i;
223 for (i = 1; i < info->hdr->e_shnum; i++) {
224 Elf_Shdr *shdr = &info->sechdrs[i];
225 /* Alloc bit cleared means "ignore it." */
226 if ((shdr->sh_flags & SHF_ALLOC)
227 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
228 return i;
230 return 0;
233 /* Find a module section, or NULL. */
234 static void *section_addr(const struct load_info *info, const char *name)
236 /* Section 0 has sh_addr 0. */
237 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
240 /* Find a module section, or NULL. Fill in number of "objects" in section. */
241 static void *section_objs(const struct load_info *info,
242 const char *name,
243 size_t object_size,
244 unsigned int *num)
246 unsigned int sec = find_sec(info, name);
248 /* Section 0 has sh_addr 0 and sh_size 0. */
249 *num = info->sechdrs[sec].sh_size / object_size;
250 return (void *)info->sechdrs[sec].sh_addr;
253 /* Provided by the linker */
254 extern const struct kernel_symbol __start___ksymtab[];
255 extern const struct kernel_symbol __stop___ksymtab[];
256 extern const struct kernel_symbol __start___ksymtab_gpl[];
257 extern const struct kernel_symbol __stop___ksymtab_gpl[];
258 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
259 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
260 extern const unsigned long __start___kcrctab[];
261 extern const unsigned long __start___kcrctab_gpl[];
262 extern const unsigned long __start___kcrctab_gpl_future[];
263 #ifdef CONFIG_UNUSED_SYMBOLS
264 extern const struct kernel_symbol __start___ksymtab_unused[];
265 extern const struct kernel_symbol __stop___ksymtab_unused[];
266 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
267 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
268 extern const unsigned long __start___kcrctab_unused[];
269 extern const unsigned long __start___kcrctab_unused_gpl[];
270 #endif
272 #ifndef CONFIG_MODVERSIONS
273 #define symversion(base, idx) NULL
274 #else
275 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
276 #endif
278 static bool each_symbol_in_section(const struct symsearch *arr,
279 unsigned int arrsize,
280 struct module *owner,
281 bool (*fn)(const struct symsearch *syms,
282 struct module *owner,
283 void *data),
284 void *data)
286 unsigned int j;
288 for (j = 0; j < arrsize; j++) {
289 if (fn(&arr[j], owner, data))
290 return true;
293 return false;
296 /* Returns true as soon as fn returns true, otherwise false. */
297 bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
298 struct module *owner,
299 void *data),
300 void *data)
302 struct module *mod;
303 static const struct symsearch arr[] = {
304 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
305 NOT_GPL_ONLY, false },
306 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
307 __start___kcrctab_gpl,
308 GPL_ONLY, false },
309 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
310 __start___kcrctab_gpl_future,
311 WILL_BE_GPL_ONLY, false },
312 #ifdef CONFIG_UNUSED_SYMBOLS
313 { __start___ksymtab_unused, __stop___ksymtab_unused,
314 __start___kcrctab_unused,
315 NOT_GPL_ONLY, true },
316 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
317 __start___kcrctab_unused_gpl,
318 GPL_ONLY, true },
319 #endif
322 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
323 return true;
325 list_for_each_entry_rcu(mod, &modules, list) {
326 struct symsearch arr[] = {
327 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
328 NOT_GPL_ONLY, false },
329 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
330 mod->gpl_crcs,
331 GPL_ONLY, false },
332 { mod->gpl_future_syms,
333 mod->gpl_future_syms + mod->num_gpl_future_syms,
334 mod->gpl_future_crcs,
335 WILL_BE_GPL_ONLY, false },
336 #ifdef CONFIG_UNUSED_SYMBOLS
337 { mod->unused_syms,
338 mod->unused_syms + mod->num_unused_syms,
339 mod->unused_crcs,
340 NOT_GPL_ONLY, true },
341 { mod->unused_gpl_syms,
342 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
343 mod->unused_gpl_crcs,
344 GPL_ONLY, true },
345 #endif
348 if (mod->state == MODULE_STATE_UNFORMED)
349 continue;
351 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
352 return true;
354 return false;
356 EXPORT_SYMBOL_GPL(each_symbol_section);
358 struct find_symbol_arg {
359 /* Input */
360 const char *name;
361 bool gplok;
362 bool warn;
364 /* Output */
365 struct module *owner;
366 const unsigned long *crc;
367 const struct kernel_symbol *sym;
370 static bool check_symbol(const struct symsearch *syms,
371 struct module *owner,
372 unsigned int symnum, void *data)
374 struct find_symbol_arg *fsa = data;
376 if (!fsa->gplok) {
377 if (syms->licence == GPL_ONLY)
378 return false;
379 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
380 pr_warn("Symbol %s is being used by a non-GPL module, "
381 "which will not be allowed in the future\n",
382 fsa->name);
386 #ifdef CONFIG_UNUSED_SYMBOLS
387 if (syms->unused && fsa->warn) {
388 pr_warn("Symbol %s is marked as UNUSED, however this module is "
389 "using it.\n", fsa->name);
390 pr_warn("This symbol will go away in the future.\n");
391 pr_warn("Please evalute if this is the right api to use and if "
392 "it really is, submit a report the linux kernel "
393 "mailinglist together with submitting your code for "
394 "inclusion.\n");
396 #endif
398 fsa->owner = owner;
399 fsa->crc = symversion(syms->crcs, symnum);
400 fsa->sym = &syms->start[symnum];
401 return true;
404 static int cmp_name(const void *va, const void *vb)
406 const char *a;
407 const struct kernel_symbol *b;
408 a = va; b = vb;
409 return strcmp(a, b->name);
412 static bool find_symbol_in_section(const struct symsearch *syms,
413 struct module *owner,
414 void *data)
416 struct find_symbol_arg *fsa = data;
417 struct kernel_symbol *sym;
419 sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
420 sizeof(struct kernel_symbol), cmp_name);
422 if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
423 return true;
425 return false;
428 /* Find a symbol and return it, along with, (optional) crc and
429 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
430 const struct kernel_symbol *find_symbol(const char *name,
431 struct module **owner,
432 const unsigned long **crc,
433 bool gplok,
434 bool warn)
436 struct find_symbol_arg fsa;
438 fsa.name = name;
439 fsa.gplok = gplok;
440 fsa.warn = warn;
442 if (each_symbol_section(find_symbol_in_section, &fsa)) {
443 if (owner)
444 *owner = fsa.owner;
445 if (crc)
446 *crc = fsa.crc;
447 return fsa.sym;
450 pr_debug("Failed to find symbol %s\n", name);
451 return NULL;
453 EXPORT_SYMBOL_GPL(find_symbol);
455 /* Search for module by name: must hold module_mutex. */
456 static struct module *find_module_all(const char *name, size_t len,
457 bool even_unformed)
459 struct module *mod;
461 list_for_each_entry(mod, &modules, list) {
462 if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
463 continue;
464 if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
465 return mod;
467 return NULL;
470 struct module *find_module(const char *name)
472 return find_module_all(name, strlen(name), false);
474 EXPORT_SYMBOL_GPL(find_module);
476 #ifdef CONFIG_SMP
478 static inline void __percpu *mod_percpu(struct module *mod)
480 return mod->percpu;
483 static int percpu_modalloc(struct module *mod, struct load_info *info)
485 Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
486 unsigned long align = pcpusec->sh_addralign;
488 if (!pcpusec->sh_size)
489 return 0;
491 if (align > PAGE_SIZE) {
492 pr_warn("%s: per-cpu alignment %li > %li\n",
493 mod->name, align, PAGE_SIZE);
494 align = PAGE_SIZE;
497 mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
498 if (!mod->percpu) {
499 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
500 mod->name, (unsigned long)pcpusec->sh_size);
501 return -ENOMEM;
503 mod->percpu_size = pcpusec->sh_size;
504 return 0;
507 static void percpu_modfree(struct module *mod)
509 free_percpu(mod->percpu);
512 static unsigned int find_pcpusec(struct load_info *info)
514 return find_sec(info, ".data..percpu");
517 static void percpu_modcopy(struct module *mod,
518 const void *from, unsigned long size)
520 int cpu;
522 for_each_possible_cpu(cpu)
523 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
527 * is_module_percpu_address - test whether address is from module static percpu
528 * @addr: address to test
530 * Test whether @addr belongs to module static percpu area.
532 * RETURNS:
533 * %true if @addr is from module static percpu area
535 bool is_module_percpu_address(unsigned long addr)
537 struct module *mod;
538 unsigned int cpu;
540 preempt_disable();
542 list_for_each_entry_rcu(mod, &modules, list) {
543 if (mod->state == MODULE_STATE_UNFORMED)
544 continue;
545 if (!mod->percpu_size)
546 continue;
547 for_each_possible_cpu(cpu) {
548 void *start = per_cpu_ptr(mod->percpu, cpu);
550 if ((void *)addr >= start &&
551 (void *)addr < start + mod->percpu_size) {
552 preempt_enable();
553 return true;
558 preempt_enable();
559 return false;
562 #else /* ... !CONFIG_SMP */
564 static inline void __percpu *mod_percpu(struct module *mod)
566 return NULL;
568 static int percpu_modalloc(struct module *mod, struct load_info *info)
570 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
571 if (info->sechdrs[info->index.pcpu].sh_size != 0)
572 return -ENOMEM;
573 return 0;
575 static inline void percpu_modfree(struct module *mod)
578 static unsigned int find_pcpusec(struct load_info *info)
580 return 0;
582 static inline void percpu_modcopy(struct module *mod,
583 const void *from, unsigned long size)
585 /* pcpusec should be 0, and size of that section should be 0. */
586 BUG_ON(size != 0);
588 bool is_module_percpu_address(unsigned long addr)
590 return false;
593 #endif /* CONFIG_SMP */
595 #define MODINFO_ATTR(field) \
596 static void setup_modinfo_##field(struct module *mod, const char *s) \
598 mod->field = kstrdup(s, GFP_KERNEL); \
600 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
601 struct module_kobject *mk, char *buffer) \
603 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
605 static int modinfo_##field##_exists(struct module *mod) \
607 return mod->field != NULL; \
609 static void free_modinfo_##field(struct module *mod) \
611 kfree(mod->field); \
612 mod->field = NULL; \
614 static struct module_attribute modinfo_##field = { \
615 .attr = { .name = __stringify(field), .mode = 0444 }, \
616 .show = show_modinfo_##field, \
617 .setup = setup_modinfo_##field, \
618 .test = modinfo_##field##_exists, \
619 .free = free_modinfo_##field, \
622 MODINFO_ATTR(version);
623 MODINFO_ATTR(srcversion);
625 static char last_unloaded_module[MODULE_NAME_LEN+1];
627 #ifdef CONFIG_MODULE_UNLOAD
629 EXPORT_TRACEPOINT_SYMBOL(module_get);
631 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
632 #define MODULE_REF_BASE 1
634 /* Init the unload section of the module. */
635 static int module_unload_init(struct module *mod)
638 * Initialize reference counter to MODULE_REF_BASE.
639 * refcnt == 0 means module is going.
641 atomic_set(&mod->refcnt, MODULE_REF_BASE);
643 INIT_LIST_HEAD(&mod->source_list);
644 INIT_LIST_HEAD(&mod->target_list);
646 /* Hold reference count during initialization. */
647 atomic_inc(&mod->refcnt);
649 return 0;
652 /* Does a already use b? */
653 static int already_uses(struct module *a, struct module *b)
655 struct module_use *use;
657 list_for_each_entry(use, &b->source_list, source_list) {
658 if (use->source == a) {
659 pr_debug("%s uses %s!\n", a->name, b->name);
660 return 1;
663 pr_debug("%s does not use %s!\n", a->name, b->name);
664 return 0;
668 * Module a uses b
669 * - we add 'a' as a "source", 'b' as a "target" of module use
670 * - the module_use is added to the list of 'b' sources (so
671 * 'b' can walk the list to see who sourced them), and of 'a'
672 * targets (so 'a' can see what modules it targets).
674 static int add_module_usage(struct module *a, struct module *b)
676 struct module_use *use;
678 pr_debug("Allocating new usage for %s.\n", a->name);
679 use = kmalloc(sizeof(*use), GFP_ATOMIC);
680 if (!use) {
681 pr_warn("%s: out of memory loading\n", a->name);
682 return -ENOMEM;
685 use->source = a;
686 use->target = b;
687 list_add(&use->source_list, &b->source_list);
688 list_add(&use->target_list, &a->target_list);
689 return 0;
692 /* Module a uses b: caller needs module_mutex() */
693 int ref_module(struct module *a, struct module *b)
695 int err;
697 if (b == NULL || already_uses(a, b))
698 return 0;
700 /* If module isn't available, we fail. */
701 err = strong_try_module_get(b);
702 if (err)
703 return err;
705 err = add_module_usage(a, b);
706 if (err) {
707 module_put(b);
708 return err;
710 return 0;
712 EXPORT_SYMBOL_GPL(ref_module);
714 /* Clear the unload stuff of the module. */
715 static void module_unload_free(struct module *mod)
717 struct module_use *use, *tmp;
719 mutex_lock(&module_mutex);
720 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
721 struct module *i = use->target;
722 pr_debug("%s unusing %s\n", mod->name, i->name);
723 module_put(i);
724 list_del(&use->source_list);
725 list_del(&use->target_list);
726 kfree(use);
728 mutex_unlock(&module_mutex);
731 #ifdef CONFIG_MODULE_FORCE_UNLOAD
732 static inline int try_force_unload(unsigned int flags)
734 int ret = (flags & O_TRUNC);
735 if (ret)
736 add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
737 return ret;
739 #else
740 static inline int try_force_unload(unsigned int flags)
742 return 0;
744 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
746 /* Try to release refcount of module, 0 means success. */
747 static int try_release_module_ref(struct module *mod)
749 int ret;
751 /* Try to decrement refcnt which we set at loading */
752 ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
753 BUG_ON(ret < 0);
754 if (ret)
755 /* Someone can put this right now, recover with checking */
756 ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
758 return ret;
761 static int try_stop_module(struct module *mod, int flags, int *forced)
763 /* If it's not unused, quit unless we're forcing. */
764 if (try_release_module_ref(mod) != 0) {
765 *forced = try_force_unload(flags);
766 if (!(*forced))
767 return -EWOULDBLOCK;
770 /* Mark it as dying. */
771 mod->state = MODULE_STATE_GOING;
773 return 0;
777 * module_refcount - return the refcount or -1 if unloading
779 * @mod: the module we're checking
781 * Returns:
782 * -1 if the module is in the process of unloading
783 * otherwise the number of references in the kernel to the module
785 int module_refcount(struct module *mod)
787 return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
789 EXPORT_SYMBOL(module_refcount);
791 /* This exists whether we can unload or not */
792 static void free_module(struct module *mod);
794 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
795 unsigned int, flags)
797 struct module *mod;
798 char name[MODULE_NAME_LEN];
799 int ret, forced = 0;
801 if (!capable(CAP_SYS_MODULE) || modules_disabled)
802 return -EPERM;
804 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
805 return -EFAULT;
806 name[MODULE_NAME_LEN-1] = '\0';
808 if (mutex_lock_interruptible(&module_mutex) != 0)
809 return -EINTR;
811 mod = find_module(name);
812 if (!mod) {
813 ret = -ENOENT;
814 goto out;
817 if (!list_empty(&mod->source_list)) {
818 /* Other modules depend on us: get rid of them first. */
819 ret = -EWOULDBLOCK;
820 goto out;
823 /* Doing init or already dying? */
824 if (mod->state != MODULE_STATE_LIVE) {
825 /* FIXME: if (force), slam module count damn the torpedoes */
826 pr_debug("%s already dying\n", mod->name);
827 ret = -EBUSY;
828 goto out;
831 /* If it has an init func, it must have an exit func to unload */
832 if (mod->init && !mod->exit) {
833 forced = try_force_unload(flags);
834 if (!forced) {
835 /* This module can't be removed */
836 ret = -EBUSY;
837 goto out;
841 /* Stop the machine so refcounts can't move and disable module. */
842 ret = try_stop_module(mod, flags, &forced);
843 if (ret != 0)
844 goto out;
846 mutex_unlock(&module_mutex);
847 /* Final destruction now no one is using it. */
848 if (mod->exit != NULL)
849 mod->exit();
850 blocking_notifier_call_chain(&module_notify_list,
851 MODULE_STATE_GOING, mod);
852 async_synchronize_full();
854 /* Store the name of the last unloaded module for diagnostic purposes */
855 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
857 free_module(mod);
858 return 0;
859 out:
860 mutex_unlock(&module_mutex);
861 return ret;
864 static inline void print_unload_info(struct seq_file *m, struct module *mod)
866 struct module_use *use;
867 int printed_something = 0;
869 seq_printf(m, " %i ", module_refcount(mod));
872 * Always include a trailing , so userspace can differentiate
873 * between this and the old multi-field proc format.
875 list_for_each_entry(use, &mod->source_list, source_list) {
876 printed_something = 1;
877 seq_printf(m, "%s,", use->source->name);
880 if (mod->init != NULL && mod->exit == NULL) {
881 printed_something = 1;
882 seq_puts(m, "[permanent],");
885 if (!printed_something)
886 seq_puts(m, "-");
889 void __symbol_put(const char *symbol)
891 struct module *owner;
893 preempt_disable();
894 if (!find_symbol(symbol, &owner, NULL, true, false))
895 BUG();
896 module_put(owner);
897 preempt_enable();
899 EXPORT_SYMBOL(__symbol_put);
901 /* Note this assumes addr is a function, which it currently always is. */
902 void symbol_put_addr(void *addr)
904 struct module *modaddr;
905 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
907 if (core_kernel_text(a))
908 return;
910 /* module_text_address is safe here: we're supposed to have reference
911 * to module from symbol_get, so it can't go away. */
912 modaddr = __module_text_address(a);
913 BUG_ON(!modaddr);
914 module_put(modaddr);
916 EXPORT_SYMBOL_GPL(symbol_put_addr);
918 static ssize_t show_refcnt(struct module_attribute *mattr,
919 struct module_kobject *mk, char *buffer)
921 return sprintf(buffer, "%i\n", module_refcount(mk->mod));
924 static struct module_attribute modinfo_refcnt =
925 __ATTR(refcnt, 0444, show_refcnt, NULL);
927 void __module_get(struct module *module)
929 if (module) {
930 preempt_disable();
931 atomic_inc(&module->refcnt);
932 trace_module_get(module, _RET_IP_);
933 preempt_enable();
936 EXPORT_SYMBOL(__module_get);
938 bool try_module_get(struct module *module)
940 bool ret = true;
942 if (module) {
943 preempt_disable();
944 /* Note: here, we can fail to get a reference */
945 if (likely(module_is_live(module) &&
946 atomic_inc_not_zero(&module->refcnt) != 0))
947 trace_module_get(module, _RET_IP_);
948 else
949 ret = false;
951 preempt_enable();
953 return ret;
955 EXPORT_SYMBOL(try_module_get);
957 void module_put(struct module *module)
959 int ret;
961 if (module) {
962 preempt_disable();
963 ret = atomic_dec_if_positive(&module->refcnt);
964 WARN_ON(ret < 0); /* Failed to put refcount */
965 trace_module_put(module, _RET_IP_);
966 preempt_enable();
969 EXPORT_SYMBOL(module_put);
971 #else /* !CONFIG_MODULE_UNLOAD */
972 static inline void print_unload_info(struct seq_file *m, struct module *mod)
974 /* We don't know the usage count, or what modules are using. */
975 seq_puts(m, " - -");
978 static inline void module_unload_free(struct module *mod)
982 int ref_module(struct module *a, struct module *b)
984 return strong_try_module_get(b);
986 EXPORT_SYMBOL_GPL(ref_module);
988 static inline int module_unload_init(struct module *mod)
990 return 0;
992 #endif /* CONFIG_MODULE_UNLOAD */
994 static size_t module_flags_taint(struct module *mod, char *buf)
996 size_t l = 0;
998 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
999 buf[l++] = 'P';
1000 if (mod->taints & (1 << TAINT_OOT_MODULE))
1001 buf[l++] = 'O';
1002 if (mod->taints & (1 << TAINT_FORCED_MODULE))
1003 buf[l++] = 'F';
1004 if (mod->taints & (1 << TAINT_CRAP))
1005 buf[l++] = 'C';
1006 if (mod->taints & (1 << TAINT_UNSIGNED_MODULE))
1007 buf[l++] = 'E';
1009 * TAINT_FORCED_RMMOD: could be added.
1010 * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
1011 * apply to modules.
1013 return l;
1016 static ssize_t show_initstate(struct module_attribute *mattr,
1017 struct module_kobject *mk, char *buffer)
1019 const char *state = "unknown";
1021 switch (mk->mod->state) {
1022 case MODULE_STATE_LIVE:
1023 state = "live";
1024 break;
1025 case MODULE_STATE_COMING:
1026 state = "coming";
1027 break;
1028 case MODULE_STATE_GOING:
1029 state = "going";
1030 break;
1031 default:
1032 BUG();
1034 return sprintf(buffer, "%s\n", state);
1037 static struct module_attribute modinfo_initstate =
1038 __ATTR(initstate, 0444, show_initstate, NULL);
1040 static ssize_t store_uevent(struct module_attribute *mattr,
1041 struct module_kobject *mk,
1042 const char *buffer, size_t count)
1044 enum kobject_action action;
1046 if (kobject_action_type(buffer, count, &action) == 0)
1047 kobject_uevent(&mk->kobj, action);
1048 return count;
1051 struct module_attribute module_uevent =
1052 __ATTR(uevent, 0200, NULL, store_uevent);
1054 static ssize_t show_coresize(struct module_attribute *mattr,
1055 struct module_kobject *mk, char *buffer)
1057 return sprintf(buffer, "%u\n", mk->mod->core_size);
1060 static struct module_attribute modinfo_coresize =
1061 __ATTR(coresize, 0444, show_coresize, NULL);
1063 static ssize_t show_initsize(struct module_attribute *mattr,
1064 struct module_kobject *mk, char *buffer)
1066 return sprintf(buffer, "%u\n", mk->mod->init_size);
1069 static struct module_attribute modinfo_initsize =
1070 __ATTR(initsize, 0444, show_initsize, NULL);
1072 static ssize_t show_taint(struct module_attribute *mattr,
1073 struct module_kobject *mk, char *buffer)
1075 size_t l;
1077 l = module_flags_taint(mk->mod, buffer);
1078 buffer[l++] = '\n';
1079 return l;
1082 static struct module_attribute modinfo_taint =
1083 __ATTR(taint, 0444, show_taint, NULL);
1085 static struct module_attribute *modinfo_attrs[] = {
1086 &module_uevent,
1087 &modinfo_version,
1088 &modinfo_srcversion,
1089 &modinfo_initstate,
1090 &modinfo_coresize,
1091 &modinfo_initsize,
1092 &modinfo_taint,
1093 #ifdef CONFIG_MODULE_UNLOAD
1094 &modinfo_refcnt,
1095 #endif
1096 NULL,
1099 static const char vermagic[] = VERMAGIC_STRING;
1101 static int try_to_force_load(struct module *mod, const char *reason)
1103 #ifdef CONFIG_MODULE_FORCE_LOAD
1104 if (!test_taint(TAINT_FORCED_MODULE))
1105 pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
1106 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
1107 return 0;
1108 #else
1109 return -ENOEXEC;
1110 #endif
1113 #ifdef CONFIG_MODVERSIONS
1114 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
1115 static unsigned long maybe_relocated(unsigned long crc,
1116 const struct module *crc_owner)
1118 #ifdef ARCH_RELOCATES_KCRCTAB
1119 if (crc_owner == NULL)
1120 return crc - (unsigned long)reloc_start;
1121 #endif
1122 return crc;
1125 static int check_version(Elf_Shdr *sechdrs,
1126 unsigned int versindex,
1127 const char *symname,
1128 struct module *mod,
1129 const unsigned long *crc,
1130 const struct module *crc_owner)
1132 unsigned int i, num_versions;
1133 struct modversion_info *versions;
1135 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1136 if (!crc)
1137 return 1;
1139 /* No versions at all? modprobe --force does this. */
1140 if (versindex == 0)
1141 return try_to_force_load(mod, symname) == 0;
1143 versions = (void *) sechdrs[versindex].sh_addr;
1144 num_versions = sechdrs[versindex].sh_size
1145 / sizeof(struct modversion_info);
1147 for (i = 0; i < num_versions; i++) {
1148 if (strcmp(versions[i].name, symname) != 0)
1149 continue;
1151 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
1152 return 1;
1153 pr_debug("Found checksum %lX vs module %lX\n",
1154 maybe_relocated(*crc, crc_owner), versions[i].crc);
1155 goto bad_version;
1158 pr_warn("%s: no symbol version for %s\n", mod->name, symname);
1159 return 0;
1161 bad_version:
1162 pr_warn("%s: disagrees about version of symbol %s\n",
1163 mod->name, symname);
1164 return 0;
1167 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1168 unsigned int versindex,
1169 struct module *mod)
1171 const unsigned long *crc;
1173 /* Since this should be found in kernel (which can't be removed),
1174 * no locking is necessary. */
1175 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
1176 &crc, true, false))
1177 BUG();
1178 return check_version(sechdrs, versindex,
1179 VMLINUX_SYMBOL_STR(module_layout), mod, crc,
1180 NULL);
1183 /* First part is kernel version, which we ignore if module has crcs. */
1184 static inline int same_magic(const char *amagic, const char *bmagic,
1185 bool has_crcs)
1187 if (has_crcs) {
1188 amagic += strcspn(amagic, " ");
1189 bmagic += strcspn(bmagic, " ");
1191 return strcmp(amagic, bmagic) == 0;
1193 #else
1194 static inline int check_version(Elf_Shdr *sechdrs,
1195 unsigned int versindex,
1196 const char *symname,
1197 struct module *mod,
1198 const unsigned long *crc,
1199 const struct module *crc_owner)
1201 return 1;
1204 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1205 unsigned int versindex,
1206 struct module *mod)
1208 return 1;
1211 static inline int same_magic(const char *amagic, const char *bmagic,
1212 bool has_crcs)
1214 return strcmp(amagic, bmagic) == 0;
1216 #endif /* CONFIG_MODVERSIONS */
1218 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1219 static const struct kernel_symbol *resolve_symbol(struct module *mod,
1220 const struct load_info *info,
1221 const char *name,
1222 char ownername[])
1224 struct module *owner;
1225 const struct kernel_symbol *sym;
1226 const unsigned long *crc;
1227 int err;
1230 * The module_mutex should not be a heavily contended lock;
1231 * if we get the occasional sleep here, we'll go an extra iteration
1232 * in the wait_event_interruptible(), which is harmless.
1234 sched_annotate_sleep();
1235 mutex_lock(&module_mutex);
1236 sym = find_symbol(name, &owner, &crc,
1237 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1238 if (!sym)
1239 goto unlock;
1241 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1242 owner)) {
1243 sym = ERR_PTR(-EINVAL);
1244 goto getname;
1247 err = ref_module(mod, owner);
1248 if (err) {
1249 sym = ERR_PTR(err);
1250 goto getname;
1253 getname:
1254 /* We must make copy under the lock if we failed to get ref. */
1255 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1256 unlock:
1257 mutex_unlock(&module_mutex);
1258 return sym;
1261 static const struct kernel_symbol *
1262 resolve_symbol_wait(struct module *mod,
1263 const struct load_info *info,
1264 const char *name)
1266 const struct kernel_symbol *ksym;
1267 char owner[MODULE_NAME_LEN];
1269 if (wait_event_interruptible_timeout(module_wq,
1270 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1271 || PTR_ERR(ksym) != -EBUSY,
1272 30 * HZ) <= 0) {
1273 pr_warn("%s: gave up waiting for init of module %s.\n",
1274 mod->name, owner);
1276 return ksym;
1280 * /sys/module/foo/sections stuff
1281 * J. Corbet <corbet@lwn.net>
1283 #ifdef CONFIG_SYSFS
1285 #ifdef CONFIG_KALLSYMS
1286 static inline bool sect_empty(const Elf_Shdr *sect)
1288 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1291 struct module_sect_attr {
1292 struct module_attribute mattr;
1293 char *name;
1294 unsigned long address;
1297 struct module_sect_attrs {
1298 struct attribute_group grp;
1299 unsigned int nsections;
1300 struct module_sect_attr attrs[0];
1303 static ssize_t module_sect_show(struct module_attribute *mattr,
1304 struct module_kobject *mk, char *buf)
1306 struct module_sect_attr *sattr =
1307 container_of(mattr, struct module_sect_attr, mattr);
1308 return sprintf(buf, "0x%pK\n", (void *)sattr->address);
1311 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1313 unsigned int section;
1315 for (section = 0; section < sect_attrs->nsections; section++)
1316 kfree(sect_attrs->attrs[section].name);
1317 kfree(sect_attrs);
1320 static void add_sect_attrs(struct module *mod, const struct load_info *info)
1322 unsigned int nloaded = 0, i, size[2];
1323 struct module_sect_attrs *sect_attrs;
1324 struct module_sect_attr *sattr;
1325 struct attribute **gattr;
1327 /* Count loaded sections and allocate structures */
1328 for (i = 0; i < info->hdr->e_shnum; i++)
1329 if (!sect_empty(&info->sechdrs[i]))
1330 nloaded++;
1331 size[0] = ALIGN(sizeof(*sect_attrs)
1332 + nloaded * sizeof(sect_attrs->attrs[0]),
1333 sizeof(sect_attrs->grp.attrs[0]));
1334 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1335 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1336 if (sect_attrs == NULL)
1337 return;
1339 /* Setup section attributes. */
1340 sect_attrs->grp.name = "sections";
1341 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1343 sect_attrs->nsections = 0;
1344 sattr = &sect_attrs->attrs[0];
1345 gattr = &sect_attrs->grp.attrs[0];
1346 for (i = 0; i < info->hdr->e_shnum; i++) {
1347 Elf_Shdr *sec = &info->sechdrs[i];
1348 if (sect_empty(sec))
1349 continue;
1350 sattr->address = sec->sh_addr;
1351 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1352 GFP_KERNEL);
1353 if (sattr->name == NULL)
1354 goto out;
1355 sect_attrs->nsections++;
1356 sysfs_attr_init(&sattr->mattr.attr);
1357 sattr->mattr.show = module_sect_show;
1358 sattr->mattr.store = NULL;
1359 sattr->mattr.attr.name = sattr->name;
1360 sattr->mattr.attr.mode = S_IRUGO;
1361 *(gattr++) = &(sattr++)->mattr.attr;
1363 *gattr = NULL;
1365 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1366 goto out;
1368 mod->sect_attrs = sect_attrs;
1369 return;
1370 out:
1371 free_sect_attrs(sect_attrs);
1374 static void remove_sect_attrs(struct module *mod)
1376 if (mod->sect_attrs) {
1377 sysfs_remove_group(&mod->mkobj.kobj,
1378 &mod->sect_attrs->grp);
1379 /* We are positive that no one is using any sect attrs
1380 * at this point. Deallocate immediately. */
1381 free_sect_attrs(mod->sect_attrs);
1382 mod->sect_attrs = NULL;
1387 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1390 struct module_notes_attrs {
1391 struct kobject *dir;
1392 unsigned int notes;
1393 struct bin_attribute attrs[0];
1396 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1397 struct bin_attribute *bin_attr,
1398 char *buf, loff_t pos, size_t count)
1401 * The caller checked the pos and count against our size.
1403 memcpy(buf, bin_attr->private + pos, count);
1404 return count;
1407 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1408 unsigned int i)
1410 if (notes_attrs->dir) {
1411 while (i-- > 0)
1412 sysfs_remove_bin_file(notes_attrs->dir,
1413 &notes_attrs->attrs[i]);
1414 kobject_put(notes_attrs->dir);
1416 kfree(notes_attrs);
1419 static void add_notes_attrs(struct module *mod, const struct load_info *info)
1421 unsigned int notes, loaded, i;
1422 struct module_notes_attrs *notes_attrs;
1423 struct bin_attribute *nattr;
1425 /* failed to create section attributes, so can't create notes */
1426 if (!mod->sect_attrs)
1427 return;
1429 /* Count notes sections and allocate structures. */
1430 notes = 0;
1431 for (i = 0; i < info->hdr->e_shnum; i++)
1432 if (!sect_empty(&info->sechdrs[i]) &&
1433 (info->sechdrs[i].sh_type == SHT_NOTE))
1434 ++notes;
1436 if (notes == 0)
1437 return;
1439 notes_attrs = kzalloc(sizeof(*notes_attrs)
1440 + notes * sizeof(notes_attrs->attrs[0]),
1441 GFP_KERNEL);
1442 if (notes_attrs == NULL)
1443 return;
1445 notes_attrs->notes = notes;
1446 nattr = &notes_attrs->attrs[0];
1447 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1448 if (sect_empty(&info->sechdrs[i]))
1449 continue;
1450 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1451 sysfs_bin_attr_init(nattr);
1452 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1453 nattr->attr.mode = S_IRUGO;
1454 nattr->size = info->sechdrs[i].sh_size;
1455 nattr->private = (void *) info->sechdrs[i].sh_addr;
1456 nattr->read = module_notes_read;
1457 ++nattr;
1459 ++loaded;
1462 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1463 if (!notes_attrs->dir)
1464 goto out;
1466 for (i = 0; i < notes; ++i)
1467 if (sysfs_create_bin_file(notes_attrs->dir,
1468 &notes_attrs->attrs[i]))
1469 goto out;
1471 mod->notes_attrs = notes_attrs;
1472 return;
1474 out:
1475 free_notes_attrs(notes_attrs, i);
1478 static void remove_notes_attrs(struct module *mod)
1480 if (mod->notes_attrs)
1481 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1484 #else
1486 static inline void add_sect_attrs(struct module *mod,
1487 const struct load_info *info)
1491 static inline void remove_sect_attrs(struct module *mod)
1495 static inline void add_notes_attrs(struct module *mod,
1496 const struct load_info *info)
1500 static inline void remove_notes_attrs(struct module *mod)
1503 #endif /* CONFIG_KALLSYMS */
1505 static void add_usage_links(struct module *mod)
1507 #ifdef CONFIG_MODULE_UNLOAD
1508 struct module_use *use;
1509 int nowarn;
1511 mutex_lock(&module_mutex);
1512 list_for_each_entry(use, &mod->target_list, target_list) {
1513 nowarn = sysfs_create_link(use->target->holders_dir,
1514 &mod->mkobj.kobj, mod->name);
1516 mutex_unlock(&module_mutex);
1517 #endif
1520 static void del_usage_links(struct module *mod)
1522 #ifdef CONFIG_MODULE_UNLOAD
1523 struct module_use *use;
1525 mutex_lock(&module_mutex);
1526 list_for_each_entry(use, &mod->target_list, target_list)
1527 sysfs_remove_link(use->target->holders_dir, mod->name);
1528 mutex_unlock(&module_mutex);
1529 #endif
1532 static int module_add_modinfo_attrs(struct module *mod)
1534 struct module_attribute *attr;
1535 struct module_attribute *temp_attr;
1536 int error = 0;
1537 int i;
1539 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1540 (ARRAY_SIZE(modinfo_attrs) + 1)),
1541 GFP_KERNEL);
1542 if (!mod->modinfo_attrs)
1543 return -ENOMEM;
1545 temp_attr = mod->modinfo_attrs;
1546 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1547 if (!attr->test ||
1548 (attr->test && attr->test(mod))) {
1549 memcpy(temp_attr, attr, sizeof(*temp_attr));
1550 sysfs_attr_init(&temp_attr->attr);
1551 error = sysfs_create_file(&mod->mkobj.kobj,
1552 &temp_attr->attr);
1553 ++temp_attr;
1556 return error;
1559 static void module_remove_modinfo_attrs(struct module *mod)
1561 struct module_attribute *attr;
1562 int i;
1564 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1565 /* pick a field to test for end of list */
1566 if (!attr->attr.name)
1567 break;
1568 sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
1569 if (attr->free)
1570 attr->free(mod);
1572 kfree(mod->modinfo_attrs);
1575 static void mod_kobject_put(struct module *mod)
1577 DECLARE_COMPLETION_ONSTACK(c);
1578 mod->mkobj.kobj_completion = &c;
1579 kobject_put(&mod->mkobj.kobj);
1580 wait_for_completion(&c);
1583 static int mod_sysfs_init(struct module *mod)
1585 int err;
1586 struct kobject *kobj;
1588 if (!module_sysfs_initialized) {
1589 pr_err("%s: module sysfs not initialized\n", mod->name);
1590 err = -EINVAL;
1591 goto out;
1594 kobj = kset_find_obj(module_kset, mod->name);
1595 if (kobj) {
1596 pr_err("%s: module is already loaded\n", mod->name);
1597 kobject_put(kobj);
1598 err = -EINVAL;
1599 goto out;
1602 mod->mkobj.mod = mod;
1604 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1605 mod->mkobj.kobj.kset = module_kset;
1606 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1607 "%s", mod->name);
1608 if (err)
1609 mod_kobject_put(mod);
1611 /* delay uevent until full sysfs population */
1612 out:
1613 return err;
1616 static int mod_sysfs_setup(struct module *mod,
1617 const struct load_info *info,
1618 struct kernel_param *kparam,
1619 unsigned int num_params)
1621 int err;
1623 err = mod_sysfs_init(mod);
1624 if (err)
1625 goto out;
1627 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1628 if (!mod->holders_dir) {
1629 err = -ENOMEM;
1630 goto out_unreg;
1633 err = module_param_sysfs_setup(mod, kparam, num_params);
1634 if (err)
1635 goto out_unreg_holders;
1637 err = module_add_modinfo_attrs(mod);
1638 if (err)
1639 goto out_unreg_param;
1641 add_usage_links(mod);
1642 add_sect_attrs(mod, info);
1643 add_notes_attrs(mod, info);
1645 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1646 return 0;
1648 out_unreg_param:
1649 module_param_sysfs_remove(mod);
1650 out_unreg_holders:
1651 kobject_put(mod->holders_dir);
1652 out_unreg:
1653 mod_kobject_put(mod);
1654 out:
1655 return err;
1658 static void mod_sysfs_fini(struct module *mod)
1660 remove_notes_attrs(mod);
1661 remove_sect_attrs(mod);
1662 mod_kobject_put(mod);
1665 #else /* !CONFIG_SYSFS */
1667 static int mod_sysfs_setup(struct module *mod,
1668 const struct load_info *info,
1669 struct kernel_param *kparam,
1670 unsigned int num_params)
1672 return 0;
1675 static void mod_sysfs_fini(struct module *mod)
1679 static void module_remove_modinfo_attrs(struct module *mod)
1683 static void del_usage_links(struct module *mod)
1687 #endif /* CONFIG_SYSFS */
1689 static void mod_sysfs_teardown(struct module *mod)
1691 del_usage_links(mod);
1692 module_remove_modinfo_attrs(mod);
1693 module_param_sysfs_remove(mod);
1694 kobject_put(mod->mkobj.drivers_dir);
1695 kobject_put(mod->holders_dir);
1696 mod_sysfs_fini(mod);
1699 #ifdef CONFIG_DEBUG_SET_MODULE_RONX
1701 * LKM RO/NX protection: protect module's text/ro-data
1702 * from modification and any data from execution.
1704 void set_page_attributes(void *start, void *end, int (*set)(unsigned long start, int num_pages))
1706 unsigned long begin_pfn = PFN_DOWN((unsigned long)start);
1707 unsigned long end_pfn = PFN_DOWN((unsigned long)end);
1709 if (end_pfn > begin_pfn)
1710 set(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1713 static void set_section_ro_nx(void *base,
1714 unsigned long text_size,
1715 unsigned long ro_size,
1716 unsigned long total_size)
1718 /* begin and end PFNs of the current subsection */
1719 unsigned long begin_pfn;
1720 unsigned long end_pfn;
1723 * Set RO for module text and RO-data:
1724 * - Always protect first page.
1725 * - Do not protect last partial page.
1727 if (ro_size > 0)
1728 set_page_attributes(base, base + ro_size, set_memory_ro);
1731 * Set NX permissions for module data:
1732 * - Do not protect first partial page.
1733 * - Always protect last page.
1735 if (total_size > text_size) {
1736 begin_pfn = PFN_UP((unsigned long)base + text_size);
1737 end_pfn = PFN_UP((unsigned long)base + total_size);
1738 if (end_pfn > begin_pfn)
1739 set_memory_nx(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1743 static void unset_module_core_ro_nx(struct module *mod)
1745 set_page_attributes(mod->module_core + mod->core_text_size,
1746 mod->module_core + mod->core_size,
1747 set_memory_x);
1748 set_page_attributes(mod->module_core,
1749 mod->module_core + mod->core_ro_size,
1750 set_memory_rw);
1753 static void unset_module_init_ro_nx(struct module *mod)
1755 set_page_attributes(mod->module_init + mod->init_text_size,
1756 mod->module_init + mod->init_size,
1757 set_memory_x);
1758 set_page_attributes(mod->module_init,
1759 mod->module_init + mod->init_ro_size,
1760 set_memory_rw);
1763 /* Iterate through all modules and set each module's text as RW */
1764 void set_all_modules_text_rw(void)
1766 struct module *mod;
1768 mutex_lock(&module_mutex);
1769 list_for_each_entry_rcu(mod, &modules, list) {
1770 if (mod->state == MODULE_STATE_UNFORMED)
1771 continue;
1772 if ((mod->module_core) && (mod->core_text_size)) {
1773 set_page_attributes(mod->module_core,
1774 mod->module_core + mod->core_text_size,
1775 set_memory_rw);
1777 if ((mod->module_init) && (mod->init_text_size)) {
1778 set_page_attributes(mod->module_init,
1779 mod->module_init + mod->init_text_size,
1780 set_memory_rw);
1783 mutex_unlock(&module_mutex);
1786 /* Iterate through all modules and set each module's text as RO */
1787 void set_all_modules_text_ro(void)
1789 struct module *mod;
1791 mutex_lock(&module_mutex);
1792 list_for_each_entry_rcu(mod, &modules, list) {
1793 if (mod->state == MODULE_STATE_UNFORMED)
1794 continue;
1795 if ((mod->module_core) && (mod->core_text_size)) {
1796 set_page_attributes(mod->module_core,
1797 mod->module_core + mod->core_text_size,
1798 set_memory_ro);
1800 if ((mod->module_init) && (mod->init_text_size)) {
1801 set_page_attributes(mod->module_init,
1802 mod->module_init + mod->init_text_size,
1803 set_memory_ro);
1806 mutex_unlock(&module_mutex);
1808 #else
1809 static inline void set_section_ro_nx(void *base, unsigned long text_size, unsigned long ro_size, unsigned long total_size) { }
1810 static void unset_module_core_ro_nx(struct module *mod) { }
1811 static void unset_module_init_ro_nx(struct module *mod) { }
1812 #endif
1814 void __weak module_memfree(void *module_region)
1816 vfree(module_region);
1817 kasan_module_free(module_region);
1820 void __weak module_arch_cleanup(struct module *mod)
1824 void __weak module_arch_freeing_init(struct module *mod)
1828 /* Free a module, remove from lists, etc. */
1829 static void free_module(struct module *mod)
1831 trace_module_free(mod);
1833 mod_sysfs_teardown(mod);
1835 /* We leave it in list to prevent duplicate loads, but make sure
1836 * that noone uses it while it's being deconstructed. */
1837 mutex_lock(&module_mutex);
1838 mod->state = MODULE_STATE_UNFORMED;
1839 mutex_unlock(&module_mutex);
1841 /* Remove dynamic debug info */
1842 ddebug_remove_module(mod->name);
1844 /* Arch-specific cleanup. */
1845 module_arch_cleanup(mod);
1847 /* Module unload stuff */
1848 module_unload_free(mod);
1850 /* Free any allocated parameters. */
1851 destroy_params(mod->kp, mod->num_kp);
1853 /* Now we can delete it from the lists */
1854 mutex_lock(&module_mutex);
1855 /* Unlink carefully: kallsyms could be walking list. */
1856 list_del_rcu(&mod->list);
1857 /* Remove this module from bug list, this uses list_del_rcu */
1858 module_bug_cleanup(mod);
1859 /* Wait for RCU synchronizing before releasing mod->list and buglist. */
1860 synchronize_rcu();
1861 mutex_unlock(&module_mutex);
1863 /* This may be NULL, but that's OK */
1864 unset_module_init_ro_nx(mod);
1865 module_arch_freeing_init(mod);
1866 module_memfree(mod->module_init);
1867 kfree(mod->args);
1868 percpu_modfree(mod);
1870 /* Free lock-classes: */
1871 lockdep_free_key_range(mod->module_core, mod->core_size);
1873 /* Finally, free the core (containing the module structure) */
1874 unset_module_core_ro_nx(mod);
1875 module_memfree(mod->module_core);
1877 #ifdef CONFIG_MPU
1878 update_protections(current->mm);
1879 #endif
1882 void *__symbol_get(const char *symbol)
1884 struct module *owner;
1885 const struct kernel_symbol *sym;
1887 preempt_disable();
1888 sym = find_symbol(symbol, &owner, NULL, true, true);
1889 if (sym && strong_try_module_get(owner))
1890 sym = NULL;
1891 preempt_enable();
1893 return sym ? (void *)sym->value : NULL;
1895 EXPORT_SYMBOL_GPL(__symbol_get);
1898 * Ensure that an exported symbol [global namespace] does not already exist
1899 * in the kernel or in some other module's exported symbol table.
1901 * You must hold the module_mutex.
1903 static int verify_export_symbols(struct module *mod)
1905 unsigned int i;
1906 struct module *owner;
1907 const struct kernel_symbol *s;
1908 struct {
1909 const struct kernel_symbol *sym;
1910 unsigned int num;
1911 } arr[] = {
1912 { mod->syms, mod->num_syms },
1913 { mod->gpl_syms, mod->num_gpl_syms },
1914 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1915 #ifdef CONFIG_UNUSED_SYMBOLS
1916 { mod->unused_syms, mod->num_unused_syms },
1917 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1918 #endif
1921 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1922 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1923 if (find_symbol(s->name, &owner, NULL, true, false)) {
1924 pr_err("%s: exports duplicate symbol %s"
1925 " (owned by %s)\n",
1926 mod->name, s->name, module_name(owner));
1927 return -ENOEXEC;
1931 return 0;
1934 /* Change all symbols so that st_value encodes the pointer directly. */
1935 static int simplify_symbols(struct module *mod, const struct load_info *info)
1937 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
1938 Elf_Sym *sym = (void *)symsec->sh_addr;
1939 unsigned long secbase;
1940 unsigned int i;
1941 int ret = 0;
1942 const struct kernel_symbol *ksym;
1944 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
1945 const char *name = info->strtab + sym[i].st_name;
1947 switch (sym[i].st_shndx) {
1948 case SHN_COMMON:
1949 /* Ignore common symbols */
1950 if (!strncmp(name, "__gnu_lto", 9))
1951 break;
1953 /* We compiled with -fno-common. These are not
1954 supposed to happen. */
1955 pr_debug("Common symbol: %s\n", name);
1956 pr_warn("%s: please compile with -fno-common\n",
1957 mod->name);
1958 ret = -ENOEXEC;
1959 break;
1961 case SHN_ABS:
1962 /* Don't need to do anything */
1963 pr_debug("Absolute symbol: 0x%08lx\n",
1964 (long)sym[i].st_value);
1965 break;
1967 case SHN_UNDEF:
1968 ksym = resolve_symbol_wait(mod, info, name);
1969 /* Ok if resolved. */
1970 if (ksym && !IS_ERR(ksym)) {
1971 sym[i].st_value = ksym->value;
1972 break;
1975 /* Ok if weak. */
1976 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1977 break;
1979 pr_warn("%s: Unknown symbol %s (err %li)\n",
1980 mod->name, name, PTR_ERR(ksym));
1981 ret = PTR_ERR(ksym) ?: -ENOENT;
1982 break;
1984 default:
1985 /* Divert to percpu allocation if a percpu var. */
1986 if (sym[i].st_shndx == info->index.pcpu)
1987 secbase = (unsigned long)mod_percpu(mod);
1988 else
1989 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
1990 sym[i].st_value += secbase;
1991 break;
1995 return ret;
1998 static int apply_relocations(struct module *mod, const struct load_info *info)
2000 unsigned int i;
2001 int err = 0;
2003 /* Now do relocations. */
2004 for (i = 1; i < info->hdr->e_shnum; i++) {
2005 unsigned int infosec = info->sechdrs[i].sh_info;
2007 /* Not a valid relocation section? */
2008 if (infosec >= info->hdr->e_shnum)
2009 continue;
2011 /* Don't bother with non-allocated sections */
2012 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
2013 continue;
2015 if (info->sechdrs[i].sh_type == SHT_REL)
2016 err = apply_relocate(info->sechdrs, info->strtab,
2017 info->index.sym, i, mod);
2018 else if (info->sechdrs[i].sh_type == SHT_RELA)
2019 err = apply_relocate_add(info->sechdrs, info->strtab,
2020 info->index.sym, i, mod);
2021 if (err < 0)
2022 break;
2024 return err;
2027 /* Additional bytes needed by arch in front of individual sections */
2028 unsigned int __weak arch_mod_section_prepend(struct module *mod,
2029 unsigned int section)
2031 /* default implementation just returns zero */
2032 return 0;
2035 /* Update size with this section: return offset. */
2036 static long get_offset(struct module *mod, unsigned int *size,
2037 Elf_Shdr *sechdr, unsigned int section)
2039 long ret;
2041 *size += arch_mod_section_prepend(mod, section);
2042 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2043 *size = ret + sechdr->sh_size;
2044 return ret;
2047 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2048 might -- code, read-only data, read-write data, small data. Tally
2049 sizes, and place the offsets into sh_entsize fields: high bit means it
2050 belongs in init. */
2051 static void layout_sections(struct module *mod, struct load_info *info)
2053 static unsigned long const masks[][2] = {
2054 /* NOTE: all executable code must be the first section
2055 * in this array; otherwise modify the text_size
2056 * finder in the two loops below */
2057 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2058 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
2059 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2060 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2062 unsigned int m, i;
2064 for (i = 0; i < info->hdr->e_shnum; i++)
2065 info->sechdrs[i].sh_entsize = ~0UL;
2067 pr_debug("Core section allocation order:\n");
2068 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2069 for (i = 0; i < info->hdr->e_shnum; ++i) {
2070 Elf_Shdr *s = &info->sechdrs[i];
2071 const char *sname = info->secstrings + s->sh_name;
2073 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2074 || (s->sh_flags & masks[m][1])
2075 || s->sh_entsize != ~0UL
2076 || strstarts(sname, ".init"))
2077 continue;
2078 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
2079 pr_debug("\t%s\n", sname);
2081 switch (m) {
2082 case 0: /* executable */
2083 mod->core_size = debug_align(mod->core_size);
2084 mod->core_text_size = mod->core_size;
2085 break;
2086 case 1: /* RO: text and ro-data */
2087 mod->core_size = debug_align(mod->core_size);
2088 mod->core_ro_size = mod->core_size;
2089 break;
2090 case 3: /* whole core */
2091 mod->core_size = debug_align(mod->core_size);
2092 break;
2096 pr_debug("Init section allocation order:\n");
2097 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2098 for (i = 0; i < info->hdr->e_shnum; ++i) {
2099 Elf_Shdr *s = &info->sechdrs[i];
2100 const char *sname = info->secstrings + s->sh_name;
2102 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2103 || (s->sh_flags & masks[m][1])
2104 || s->sh_entsize != ~0UL
2105 || !strstarts(sname, ".init"))
2106 continue;
2107 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
2108 | INIT_OFFSET_MASK);
2109 pr_debug("\t%s\n", sname);
2111 switch (m) {
2112 case 0: /* executable */
2113 mod->init_size = debug_align(mod->init_size);
2114 mod->init_text_size = mod->init_size;
2115 break;
2116 case 1: /* RO: text and ro-data */
2117 mod->init_size = debug_align(mod->init_size);
2118 mod->init_ro_size = mod->init_size;
2119 break;
2120 case 3: /* whole init */
2121 mod->init_size = debug_align(mod->init_size);
2122 break;
2127 static void set_license(struct module *mod, const char *license)
2129 if (!license)
2130 license = "unspecified";
2132 if (!license_is_gpl_compatible(license)) {
2133 if (!test_taint(TAINT_PROPRIETARY_MODULE))
2134 pr_warn("%s: module license '%s' taints kernel.\n",
2135 mod->name, license);
2136 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2137 LOCKDEP_NOW_UNRELIABLE);
2141 /* Parse tag=value strings from .modinfo section */
2142 static char *next_string(char *string, unsigned long *secsize)
2144 /* Skip non-zero chars */
2145 while (string[0]) {
2146 string++;
2147 if ((*secsize)-- <= 1)
2148 return NULL;
2151 /* Skip any zero padding. */
2152 while (!string[0]) {
2153 string++;
2154 if ((*secsize)-- <= 1)
2155 return NULL;
2157 return string;
2160 static char *get_modinfo(struct load_info *info, const char *tag)
2162 char *p;
2163 unsigned int taglen = strlen(tag);
2164 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2165 unsigned long size = infosec->sh_size;
2167 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
2168 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2169 return p + taglen + 1;
2171 return NULL;
2174 static void setup_modinfo(struct module *mod, struct load_info *info)
2176 struct module_attribute *attr;
2177 int i;
2179 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2180 if (attr->setup)
2181 attr->setup(mod, get_modinfo(info, attr->attr.name));
2185 static void free_modinfo(struct module *mod)
2187 struct module_attribute *attr;
2188 int i;
2190 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2191 if (attr->free)
2192 attr->free(mod);
2196 #ifdef CONFIG_KALLSYMS
2198 /* lookup symbol in given range of kernel_symbols */
2199 static const struct kernel_symbol *lookup_symbol(const char *name,
2200 const struct kernel_symbol *start,
2201 const struct kernel_symbol *stop)
2203 return bsearch(name, start, stop - start,
2204 sizeof(struct kernel_symbol), cmp_name);
2207 static int is_exported(const char *name, unsigned long value,
2208 const struct module *mod)
2210 const struct kernel_symbol *ks;
2211 if (!mod)
2212 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
2213 else
2214 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
2215 return ks != NULL && ks->value == value;
2218 /* As per nm */
2219 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
2221 const Elf_Shdr *sechdrs = info->sechdrs;
2223 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2224 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2225 return 'v';
2226 else
2227 return 'w';
2229 if (sym->st_shndx == SHN_UNDEF)
2230 return 'U';
2231 if (sym->st_shndx == SHN_ABS)
2232 return 'a';
2233 if (sym->st_shndx >= SHN_LORESERVE)
2234 return '?';
2235 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2236 return 't';
2237 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2238 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2239 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2240 return 'r';
2241 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2242 return 'g';
2243 else
2244 return 'd';
2246 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2247 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2248 return 's';
2249 else
2250 return 'b';
2252 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2253 ".debug")) {
2254 return 'n';
2256 return '?';
2259 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
2260 unsigned int shnum)
2262 const Elf_Shdr *sec;
2264 if (src->st_shndx == SHN_UNDEF
2265 || src->st_shndx >= shnum
2266 || !src->st_name)
2267 return false;
2269 sec = sechdrs + src->st_shndx;
2270 if (!(sec->sh_flags & SHF_ALLOC)
2271 #ifndef CONFIG_KALLSYMS_ALL
2272 || !(sec->sh_flags & SHF_EXECINSTR)
2273 #endif
2274 || (sec->sh_entsize & INIT_OFFSET_MASK))
2275 return false;
2277 return true;
2281 * We only allocate and copy the strings needed by the parts of symtab
2282 * we keep. This is simple, but has the effect of making multiple
2283 * copies of duplicates. We could be more sophisticated, see
2284 * linux-kernel thread starting with
2285 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2287 static void layout_symtab(struct module *mod, struct load_info *info)
2289 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2290 Elf_Shdr *strsect = info->sechdrs + info->index.str;
2291 const Elf_Sym *src;
2292 unsigned int i, nsrc, ndst, strtab_size = 0;
2294 /* Put symbol section at end of init part of module. */
2295 symsect->sh_flags |= SHF_ALLOC;
2296 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
2297 info->index.sym) | INIT_OFFSET_MASK;
2298 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
2300 src = (void *)info->hdr + symsect->sh_offset;
2301 nsrc = symsect->sh_size / sizeof(*src);
2303 /* Compute total space required for the core symbols' strtab. */
2304 for (ndst = i = 0; i < nsrc; i++) {
2305 if (i == 0 ||
2306 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2307 strtab_size += strlen(&info->strtab[src[i].st_name])+1;
2308 ndst++;
2312 /* Append room for core symbols at end of core part. */
2313 info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
2314 info->stroffs = mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym);
2315 mod->core_size += strtab_size;
2317 /* Put string table section at end of init part of module. */
2318 strsect->sh_flags |= SHF_ALLOC;
2319 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
2320 info->index.str) | INIT_OFFSET_MASK;
2321 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
2324 static void add_kallsyms(struct module *mod, const struct load_info *info)
2326 unsigned int i, ndst;
2327 const Elf_Sym *src;
2328 Elf_Sym *dst;
2329 char *s;
2330 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2332 mod->symtab = (void *)symsec->sh_addr;
2333 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2334 /* Make sure we get permanent strtab: don't use info->strtab. */
2335 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2337 /* Set types up while we still have access to sections. */
2338 for (i = 0; i < mod->num_symtab; i++)
2339 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
2341 mod->core_symtab = dst = mod->module_core + info->symoffs;
2342 mod->core_strtab = s = mod->module_core + info->stroffs;
2343 src = mod->symtab;
2344 for (ndst = i = 0; i < mod->num_symtab; i++) {
2345 if (i == 0 ||
2346 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2347 dst[ndst] = src[i];
2348 dst[ndst++].st_name = s - mod->core_strtab;
2349 s += strlcpy(s, &mod->strtab[src[i].st_name],
2350 KSYM_NAME_LEN) + 1;
2353 mod->core_num_syms = ndst;
2355 #else
2356 static inline void layout_symtab(struct module *mod, struct load_info *info)
2360 static void add_kallsyms(struct module *mod, const struct load_info *info)
2363 #endif /* CONFIG_KALLSYMS */
2365 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2367 if (!debug)
2368 return;
2369 #ifdef CONFIG_DYNAMIC_DEBUG
2370 if (ddebug_add_module(debug, num, debug->modname))
2371 pr_err("dynamic debug error adding module: %s\n",
2372 debug->modname);
2373 #endif
2376 static void dynamic_debug_remove(struct _ddebug *debug)
2378 if (debug)
2379 ddebug_remove_module(debug->modname);
2382 void * __weak module_alloc(unsigned long size)
2384 return vmalloc_exec(size);
2387 static void *module_alloc_update_bounds(unsigned long size)
2389 void *ret = module_alloc(size);
2391 if (ret) {
2392 mutex_lock(&module_mutex);
2393 /* Update module bounds. */
2394 if ((unsigned long)ret < module_addr_min)
2395 module_addr_min = (unsigned long)ret;
2396 if ((unsigned long)ret + size > module_addr_max)
2397 module_addr_max = (unsigned long)ret + size;
2398 mutex_unlock(&module_mutex);
2400 return ret;
2403 #ifdef CONFIG_DEBUG_KMEMLEAK
2404 static void kmemleak_load_module(const struct module *mod,
2405 const struct load_info *info)
2407 unsigned int i;
2409 /* only scan the sections containing data */
2410 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2412 for (i = 1; i < info->hdr->e_shnum; i++) {
2413 /* Scan all writable sections that's not executable */
2414 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
2415 !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
2416 (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
2417 continue;
2419 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2420 info->sechdrs[i].sh_size, GFP_KERNEL);
2423 #else
2424 static inline void kmemleak_load_module(const struct module *mod,
2425 const struct load_info *info)
2428 #endif
2430 #ifdef CONFIG_MODULE_SIG
2431 static int module_sig_check(struct load_info *info)
2433 int err = -ENOKEY;
2434 const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2435 const void *mod = info->hdr;
2437 if (info->len > markerlen &&
2438 memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
2439 /* We truncate the module to discard the signature */
2440 info->len -= markerlen;
2441 err = mod_verify_sig(mod, &info->len);
2444 if (!err) {
2445 info->sig_ok = true;
2446 return 0;
2449 /* Not having a signature is only an error if we're strict. */
2450 if (err == -ENOKEY && !sig_enforce)
2451 err = 0;
2453 return err;
2455 #else /* !CONFIG_MODULE_SIG */
2456 static int module_sig_check(struct load_info *info)
2458 return 0;
2460 #endif /* !CONFIG_MODULE_SIG */
2462 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2463 static int elf_header_check(struct load_info *info)
2465 if (info->len < sizeof(*(info->hdr)))
2466 return -ENOEXEC;
2468 if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2469 || info->hdr->e_type != ET_REL
2470 || !elf_check_arch(info->hdr)
2471 || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2472 return -ENOEXEC;
2474 if (info->hdr->e_shoff >= info->len
2475 || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2476 info->len - info->hdr->e_shoff))
2477 return -ENOEXEC;
2479 return 0;
2482 /* Sets info->hdr and info->len. */
2483 static int copy_module_from_user(const void __user *umod, unsigned long len,
2484 struct load_info *info)
2486 int err;
2488 info->len = len;
2489 if (info->len < sizeof(*(info->hdr)))
2490 return -ENOEXEC;
2492 err = security_kernel_module_from_file(NULL);
2493 if (err)
2494 return err;
2496 /* Suck in entire file: we'll want most of it. */
2497 info->hdr = vmalloc(info->len);
2498 if (!info->hdr)
2499 return -ENOMEM;
2501 if (copy_from_user(info->hdr, umod, info->len) != 0) {
2502 vfree(info->hdr);
2503 return -EFAULT;
2506 return 0;
2509 /* Sets info->hdr and info->len. */
2510 static int copy_module_from_fd(int fd, struct load_info *info)
2512 struct fd f = fdget(fd);
2513 int err;
2514 struct kstat stat;
2515 loff_t pos;
2516 ssize_t bytes = 0;
2518 if (!f.file)
2519 return -ENOEXEC;
2521 err = security_kernel_module_from_file(f.file);
2522 if (err)
2523 goto out;
2525 err = vfs_getattr(&f.file->f_path, &stat);
2526 if (err)
2527 goto out;
2529 if (stat.size > INT_MAX) {
2530 err = -EFBIG;
2531 goto out;
2534 /* Don't hand 0 to vmalloc, it whines. */
2535 if (stat.size == 0) {
2536 err = -EINVAL;
2537 goto out;
2540 info->hdr = vmalloc(stat.size);
2541 if (!info->hdr) {
2542 err = -ENOMEM;
2543 goto out;
2546 pos = 0;
2547 while (pos < stat.size) {
2548 bytes = kernel_read(f.file, pos, (char *)(info->hdr) + pos,
2549 stat.size - pos);
2550 if (bytes < 0) {
2551 vfree(info->hdr);
2552 err = bytes;
2553 goto out;
2555 if (bytes == 0)
2556 break;
2557 pos += bytes;
2559 info->len = pos;
2561 out:
2562 fdput(f);
2563 return err;
2566 static void free_copy(struct load_info *info)
2568 vfree(info->hdr);
2571 static int rewrite_section_headers(struct load_info *info, int flags)
2573 unsigned int i;
2575 /* This should always be true, but let's be sure. */
2576 info->sechdrs[0].sh_addr = 0;
2578 for (i = 1; i < info->hdr->e_shnum; i++) {
2579 Elf_Shdr *shdr = &info->sechdrs[i];
2580 if (shdr->sh_type != SHT_NOBITS
2581 && info->len < shdr->sh_offset + shdr->sh_size) {
2582 pr_err("Module len %lu truncated\n", info->len);
2583 return -ENOEXEC;
2586 /* Mark all sections sh_addr with their address in the
2587 temporary image. */
2588 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2590 #ifndef CONFIG_MODULE_UNLOAD
2591 /* Don't load .exit sections */
2592 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2593 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2594 #endif
2597 /* Track but don't keep modinfo and version sections. */
2598 if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
2599 info->index.vers = 0; /* Pretend no __versions section! */
2600 else
2601 info->index.vers = find_sec(info, "__versions");
2602 info->index.info = find_sec(info, ".modinfo");
2603 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2604 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2605 return 0;
2609 * Set up our basic convenience variables (pointers to section headers,
2610 * search for module section index etc), and do some basic section
2611 * verification.
2613 * Return the temporary module pointer (we'll replace it with the final
2614 * one when we move the module sections around).
2616 static struct module *setup_load_info(struct load_info *info, int flags)
2618 unsigned int i;
2619 int err;
2620 struct module *mod;
2622 /* Set up the convenience variables */
2623 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2624 info->secstrings = (void *)info->hdr
2625 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2627 err = rewrite_section_headers(info, flags);
2628 if (err)
2629 return ERR_PTR(err);
2631 /* Find internal symbols and strings. */
2632 for (i = 1; i < info->hdr->e_shnum; i++) {
2633 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2634 info->index.sym = i;
2635 info->index.str = info->sechdrs[i].sh_link;
2636 info->strtab = (char *)info->hdr
2637 + info->sechdrs[info->index.str].sh_offset;
2638 break;
2642 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
2643 if (!info->index.mod) {
2644 pr_warn("No module found in object\n");
2645 return ERR_PTR(-ENOEXEC);
2647 /* This is temporary: point mod into copy of data. */
2648 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2650 if (info->index.sym == 0) {
2651 pr_warn("%s: module has no symbols (stripped?)\n", mod->name);
2652 return ERR_PTR(-ENOEXEC);
2655 info->index.pcpu = find_pcpusec(info);
2657 /* Check module struct version now, before we try to use module. */
2658 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2659 return ERR_PTR(-ENOEXEC);
2661 return mod;
2664 static int check_modinfo(struct module *mod, struct load_info *info, int flags)
2666 const char *modmagic = get_modinfo(info, "vermagic");
2667 int err;
2669 if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2670 modmagic = NULL;
2672 /* This is allowed: modprobe --force will invalidate it. */
2673 if (!modmagic) {
2674 err = try_to_force_load(mod, "bad vermagic");
2675 if (err)
2676 return err;
2677 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2678 pr_err("%s: version magic '%s' should be '%s'\n",
2679 mod->name, modmagic, vermagic);
2680 return -ENOEXEC;
2683 if (!get_modinfo(info, "intree"))
2684 add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
2686 if (get_modinfo(info, "staging")) {
2687 add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
2688 pr_warn("%s: module is from the staging directory, the quality "
2689 "is unknown, you have been warned.\n", mod->name);
2692 /* Set up license info based on the info section */
2693 set_license(mod, get_modinfo(info, "license"));
2695 return 0;
2698 static int find_module_sections(struct module *mod, struct load_info *info)
2700 mod->kp = section_objs(info, "__param",
2701 sizeof(*mod->kp), &mod->num_kp);
2702 mod->syms = section_objs(info, "__ksymtab",
2703 sizeof(*mod->syms), &mod->num_syms);
2704 mod->crcs = section_addr(info, "__kcrctab");
2705 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2706 sizeof(*mod->gpl_syms),
2707 &mod->num_gpl_syms);
2708 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2709 mod->gpl_future_syms = section_objs(info,
2710 "__ksymtab_gpl_future",
2711 sizeof(*mod->gpl_future_syms),
2712 &mod->num_gpl_future_syms);
2713 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
2715 #ifdef CONFIG_UNUSED_SYMBOLS
2716 mod->unused_syms = section_objs(info, "__ksymtab_unused",
2717 sizeof(*mod->unused_syms),
2718 &mod->num_unused_syms);
2719 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2720 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
2721 sizeof(*mod->unused_gpl_syms),
2722 &mod->num_unused_gpl_syms);
2723 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
2724 #endif
2725 #ifdef CONFIG_CONSTRUCTORS
2726 mod->ctors = section_objs(info, ".ctors",
2727 sizeof(*mod->ctors), &mod->num_ctors);
2728 if (!mod->ctors)
2729 mod->ctors = section_objs(info, ".init_array",
2730 sizeof(*mod->ctors), &mod->num_ctors);
2731 else if (find_sec(info, ".init_array")) {
2733 * This shouldn't happen with same compiler and binutils
2734 * building all parts of the module.
2736 pr_warn("%s: has both .ctors and .init_array.\n",
2737 mod->name);
2738 return -EINVAL;
2740 #endif
2742 #ifdef CONFIG_TRACEPOINTS
2743 mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2744 sizeof(*mod->tracepoints_ptrs),
2745 &mod->num_tracepoints);
2746 #endif
2747 #ifdef HAVE_JUMP_LABEL
2748 mod->jump_entries = section_objs(info, "__jump_table",
2749 sizeof(*mod->jump_entries),
2750 &mod->num_jump_entries);
2751 #endif
2752 #ifdef CONFIG_EVENT_TRACING
2753 mod->trace_events = section_objs(info, "_ftrace_events",
2754 sizeof(*mod->trace_events),
2755 &mod->num_trace_events);
2756 #endif
2757 #ifdef CONFIG_TRACING
2758 mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2759 sizeof(*mod->trace_bprintk_fmt_start),
2760 &mod->num_trace_bprintk_fmt);
2761 #endif
2762 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2763 /* sechdrs[0].sh_size is always zero */
2764 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
2765 sizeof(*mod->ftrace_callsites),
2766 &mod->num_ftrace_callsites);
2767 #endif
2769 mod->extable = section_objs(info, "__ex_table",
2770 sizeof(*mod->extable), &mod->num_exentries);
2772 if (section_addr(info, "__obsparm"))
2773 pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
2775 info->debug = section_objs(info, "__verbose",
2776 sizeof(*info->debug), &info->num_debug);
2778 return 0;
2781 static int move_module(struct module *mod, struct load_info *info)
2783 int i;
2784 void *ptr;
2786 /* Do the allocs. */
2787 ptr = module_alloc_update_bounds(mod->core_size);
2789 * The pointer to this block is stored in the module structure
2790 * which is inside the block. Just mark it as not being a
2791 * leak.
2793 kmemleak_not_leak(ptr);
2794 if (!ptr)
2795 return -ENOMEM;
2797 memset(ptr, 0, mod->core_size);
2798 mod->module_core = ptr;
2800 if (mod->init_size) {
2801 ptr = module_alloc_update_bounds(mod->init_size);
2803 * The pointer to this block is stored in the module structure
2804 * which is inside the block. This block doesn't need to be
2805 * scanned as it contains data and code that will be freed
2806 * after the module is initialized.
2808 kmemleak_ignore(ptr);
2809 if (!ptr) {
2810 module_memfree(mod->module_core);
2811 return -ENOMEM;
2813 memset(ptr, 0, mod->init_size);
2814 mod->module_init = ptr;
2815 } else
2816 mod->module_init = NULL;
2818 /* Transfer each section which specifies SHF_ALLOC */
2819 pr_debug("final section addresses:\n");
2820 for (i = 0; i < info->hdr->e_shnum; i++) {
2821 void *dest;
2822 Elf_Shdr *shdr = &info->sechdrs[i];
2824 if (!(shdr->sh_flags & SHF_ALLOC))
2825 continue;
2827 if (shdr->sh_entsize & INIT_OFFSET_MASK)
2828 dest = mod->module_init
2829 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
2830 else
2831 dest = mod->module_core + shdr->sh_entsize;
2833 if (shdr->sh_type != SHT_NOBITS)
2834 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2835 /* Update sh_addr to point to copy in image. */
2836 shdr->sh_addr = (unsigned long)dest;
2837 pr_debug("\t0x%lx %s\n",
2838 (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
2841 return 0;
2844 static int check_module_license_and_versions(struct module *mod)
2847 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2848 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2849 * using GPL-only symbols it needs.
2851 if (strcmp(mod->name, "ndiswrapper") == 0)
2852 add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
2854 /* driverloader was caught wrongly pretending to be under GPL */
2855 if (strcmp(mod->name, "driverloader") == 0)
2856 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2857 LOCKDEP_NOW_UNRELIABLE);
2859 /* lve claims to be GPL but upstream won't provide source */
2860 if (strcmp(mod->name, "lve") == 0)
2861 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2862 LOCKDEP_NOW_UNRELIABLE);
2864 #ifdef CONFIG_MODVERSIONS
2865 if ((mod->num_syms && !mod->crcs)
2866 || (mod->num_gpl_syms && !mod->gpl_crcs)
2867 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2868 #ifdef CONFIG_UNUSED_SYMBOLS
2869 || (mod->num_unused_syms && !mod->unused_crcs)
2870 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2871 #endif
2873 return try_to_force_load(mod,
2874 "no versions for exported symbols");
2876 #endif
2877 return 0;
2880 static void flush_module_icache(const struct module *mod)
2882 mm_segment_t old_fs;
2884 /* flush the icache in correct context */
2885 old_fs = get_fs();
2886 set_fs(KERNEL_DS);
2889 * Flush the instruction cache, since we've played with text.
2890 * Do it before processing of module parameters, so the module
2891 * can provide parameter accessor functions of its own.
2893 if (mod->module_init)
2894 flush_icache_range((unsigned long)mod->module_init,
2895 (unsigned long)mod->module_init
2896 + mod->init_size);
2897 flush_icache_range((unsigned long)mod->module_core,
2898 (unsigned long)mod->module_core + mod->core_size);
2900 set_fs(old_fs);
2903 int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
2904 Elf_Shdr *sechdrs,
2905 char *secstrings,
2906 struct module *mod)
2908 return 0;
2911 static struct module *layout_and_allocate(struct load_info *info, int flags)
2913 /* Module within temporary copy. */
2914 struct module *mod;
2915 int err;
2917 mod = setup_load_info(info, flags);
2918 if (IS_ERR(mod))
2919 return mod;
2921 err = check_modinfo(mod, info, flags);
2922 if (err)
2923 return ERR_PTR(err);
2925 /* Allow arches to frob section contents and sizes. */
2926 err = module_frob_arch_sections(info->hdr, info->sechdrs,
2927 info->secstrings, mod);
2928 if (err < 0)
2929 return ERR_PTR(err);
2931 /* We will do a special allocation for per-cpu sections later. */
2932 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
2934 /* Determine total sizes, and put offsets in sh_entsize. For now
2935 this is done generically; there doesn't appear to be any
2936 special cases for the architectures. */
2937 layout_sections(mod, info);
2938 layout_symtab(mod, info);
2940 /* Allocate and move to the final place */
2941 err = move_module(mod, info);
2942 if (err)
2943 return ERR_PTR(err);
2945 /* Module has been copied to its final place now: return it. */
2946 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2947 kmemleak_load_module(mod, info);
2948 return mod;
2951 /* mod is no longer valid after this! */
2952 static void module_deallocate(struct module *mod, struct load_info *info)
2954 percpu_modfree(mod);
2955 module_arch_freeing_init(mod);
2956 module_memfree(mod->module_init);
2957 module_memfree(mod->module_core);
2960 int __weak module_finalize(const Elf_Ehdr *hdr,
2961 const Elf_Shdr *sechdrs,
2962 struct module *me)
2964 return 0;
2967 static int post_relocation(struct module *mod, const struct load_info *info)
2969 /* Sort exception table now relocations are done. */
2970 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2972 /* Copy relocated percpu area over. */
2973 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
2974 info->sechdrs[info->index.pcpu].sh_size);
2976 /* Setup kallsyms-specific fields. */
2977 add_kallsyms(mod, info);
2979 /* Arch-specific module finalizing. */
2980 return module_finalize(info->hdr, info->sechdrs, mod);
2983 /* Is this module of this name done loading? No locks held. */
2984 static bool finished_loading(const char *name)
2986 struct module *mod;
2987 bool ret;
2990 * The module_mutex should not be a heavily contended lock;
2991 * if we get the occasional sleep here, we'll go an extra iteration
2992 * in the wait_event_interruptible(), which is harmless.
2994 sched_annotate_sleep();
2995 mutex_lock(&module_mutex);
2996 mod = find_module_all(name, strlen(name), true);
2997 ret = !mod || mod->state == MODULE_STATE_LIVE
2998 || mod->state == MODULE_STATE_GOING;
2999 mutex_unlock(&module_mutex);
3001 return ret;
3004 /* Call module constructors. */
3005 static void do_mod_ctors(struct module *mod)
3007 #ifdef CONFIG_CONSTRUCTORS
3008 unsigned long i;
3010 for (i = 0; i < mod->num_ctors; i++)
3011 mod->ctors[i]();
3012 #endif
3015 /* For freeing module_init on success, in case kallsyms traversing */
3016 struct mod_initfree {
3017 struct rcu_head rcu;
3018 void *module_init;
3021 static void do_free_init(struct rcu_head *head)
3023 struct mod_initfree *m = container_of(head, struct mod_initfree, rcu);
3024 module_memfree(m->module_init);
3025 kfree(m);
3029 * This is where the real work happens.
3031 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3032 * helper command 'lx-symbols'.
3034 static noinline int do_init_module(struct module *mod)
3036 int ret = 0;
3037 struct mod_initfree *freeinit;
3039 freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
3040 if (!freeinit) {
3041 ret = -ENOMEM;
3042 goto fail;
3044 freeinit->module_init = mod->module_init;
3047 * We want to find out whether @mod uses async during init. Clear
3048 * PF_USED_ASYNC. async_schedule*() will set it.
3050 current->flags &= ~PF_USED_ASYNC;
3052 do_mod_ctors(mod);
3053 /* Start the module */
3054 if (mod->init != NULL)
3055 ret = do_one_initcall(mod->init);
3056 if (ret < 0) {
3057 goto fail_free_freeinit;
3059 if (ret > 0) {
3060 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3061 "follow 0/-E convention\n"
3062 "%s: loading module anyway...\n",
3063 __func__, mod->name, ret, __func__);
3064 dump_stack();
3067 /* Now it's a first class citizen! */
3068 mod->state = MODULE_STATE_LIVE;
3069 blocking_notifier_call_chain(&module_notify_list,
3070 MODULE_STATE_LIVE, mod);
3073 * We need to finish all async code before the module init sequence
3074 * is done. This has potential to deadlock. For example, a newly
3075 * detected block device can trigger request_module() of the
3076 * default iosched from async probing task. Once userland helper
3077 * reaches here, async_synchronize_full() will wait on the async
3078 * task waiting on request_module() and deadlock.
3080 * This deadlock is avoided by perfomring async_synchronize_full()
3081 * iff module init queued any async jobs. This isn't a full
3082 * solution as it will deadlock the same if module loading from
3083 * async jobs nests more than once; however, due to the various
3084 * constraints, this hack seems to be the best option for now.
3085 * Please refer to the following thread for details.
3087 * http://thread.gmane.org/gmane.linux.kernel/1420814
3089 if (current->flags & PF_USED_ASYNC)
3090 async_synchronize_full();
3092 mutex_lock(&module_mutex);
3093 /* Drop initial reference. */
3094 module_put(mod);
3095 trim_init_extable(mod);
3096 #ifdef CONFIG_KALLSYMS
3097 mod->num_symtab = mod->core_num_syms;
3098 mod->symtab = mod->core_symtab;
3099 mod->strtab = mod->core_strtab;
3100 #endif
3101 unset_module_init_ro_nx(mod);
3102 module_arch_freeing_init(mod);
3103 mod->module_init = NULL;
3104 mod->init_size = 0;
3105 mod->init_ro_size = 0;
3106 mod->init_text_size = 0;
3108 * We want to free module_init, but be aware that kallsyms may be
3109 * walking this with preempt disabled. In all the failure paths,
3110 * we call synchronize_rcu/synchronize_sched, but we don't want
3111 * to slow down the success path, so use actual RCU here.
3113 call_rcu(&freeinit->rcu, do_free_init);
3114 mutex_unlock(&module_mutex);
3115 wake_up_all(&module_wq);
3117 return 0;
3119 fail_free_freeinit:
3120 kfree(freeinit);
3121 fail:
3122 /* Try to protect us from buggy refcounters. */
3123 mod->state = MODULE_STATE_GOING;
3124 synchronize_sched();
3125 module_put(mod);
3126 blocking_notifier_call_chain(&module_notify_list,
3127 MODULE_STATE_GOING, mod);
3128 free_module(mod);
3129 wake_up_all(&module_wq);
3130 return ret;
3133 static int may_init_module(void)
3135 if (!capable(CAP_SYS_MODULE) || modules_disabled)
3136 return -EPERM;
3138 return 0;
3142 * We try to place it in the list now to make sure it's unique before
3143 * we dedicate too many resources. In particular, temporary percpu
3144 * memory exhaustion.
3146 static int add_unformed_module(struct module *mod)
3148 int err;
3149 struct module *old;
3151 mod->state = MODULE_STATE_UNFORMED;
3153 again:
3154 mutex_lock(&module_mutex);
3155 old = find_module_all(mod->name, strlen(mod->name), true);
3156 if (old != NULL) {
3157 if (old->state == MODULE_STATE_COMING
3158 || old->state == MODULE_STATE_UNFORMED) {
3159 /* Wait in case it fails to load. */
3160 mutex_unlock(&module_mutex);
3161 err = wait_event_interruptible(module_wq,
3162 finished_loading(mod->name));
3163 if (err)
3164 goto out_unlocked;
3165 goto again;
3167 err = -EEXIST;
3168 goto out;
3170 list_add_rcu(&mod->list, &modules);
3171 err = 0;
3173 out:
3174 mutex_unlock(&module_mutex);
3175 out_unlocked:
3176 return err;
3179 static int complete_formation(struct module *mod, struct load_info *info)
3181 int err;
3183 mutex_lock(&module_mutex);
3185 /* Find duplicate symbols (must be called under lock). */
3186 err = verify_export_symbols(mod);
3187 if (err < 0)
3188 goto out;
3190 /* This relies on module_mutex for list integrity. */
3191 module_bug_finalize(info->hdr, info->sechdrs, mod);
3193 /* Set RO and NX regions for core */
3194 set_section_ro_nx(mod->module_core,
3195 mod->core_text_size,
3196 mod->core_ro_size,
3197 mod->core_size);
3199 /* Set RO and NX regions for init */
3200 set_section_ro_nx(mod->module_init,
3201 mod->init_text_size,
3202 mod->init_ro_size,
3203 mod->init_size);
3205 /* Mark state as coming so strong_try_module_get() ignores us,
3206 * but kallsyms etc. can see us. */
3207 mod->state = MODULE_STATE_COMING;
3208 mutex_unlock(&module_mutex);
3210 blocking_notifier_call_chain(&module_notify_list,
3211 MODULE_STATE_COMING, mod);
3212 return 0;
3214 out:
3215 mutex_unlock(&module_mutex);
3216 return err;
3219 static int unknown_module_param_cb(char *param, char *val, const char *modname)
3221 /* Check for magic 'dyndbg' arg */
3222 int ret = ddebug_dyndbg_module_param_cb(param, val, modname);
3223 if (ret != 0)
3224 pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
3225 return 0;
3228 /* Allocate and load the module: note that size of section 0 is always
3229 zero, and we rely on this for optional sections. */
3230 static int load_module(struct load_info *info, const char __user *uargs,
3231 int flags)
3233 struct module *mod;
3234 long err;
3235 char *after_dashes;
3237 err = module_sig_check(info);
3238 if (err)
3239 goto free_copy;
3241 err = elf_header_check(info);
3242 if (err)
3243 goto free_copy;
3245 /* Figure out module layout, and allocate all the memory. */
3246 mod = layout_and_allocate(info, flags);
3247 if (IS_ERR(mod)) {
3248 err = PTR_ERR(mod);
3249 goto free_copy;
3252 /* Reserve our place in the list. */
3253 err = add_unformed_module(mod);
3254 if (err)
3255 goto free_module;
3257 #ifdef CONFIG_MODULE_SIG
3258 mod->sig_ok = info->sig_ok;
3259 if (!mod->sig_ok) {
3260 pr_notice_once("%s: module verification failed: signature "
3261 "and/or required key missing - tainting "
3262 "kernel\n", mod->name);
3263 add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
3265 #endif
3267 /* To avoid stressing percpu allocator, do this once we're unique. */
3268 err = percpu_modalloc(mod, info);
3269 if (err)
3270 goto unlink_mod;
3272 /* Now module is in final location, initialize linked lists, etc. */
3273 err = module_unload_init(mod);
3274 if (err)
3275 goto unlink_mod;
3277 /* Now we've got everything in the final locations, we can
3278 * find optional sections. */
3279 err = find_module_sections(mod, info);
3280 if (err)
3281 goto free_unload;
3283 err = check_module_license_and_versions(mod);
3284 if (err)
3285 goto free_unload;
3287 /* Set up MODINFO_ATTR fields */
3288 setup_modinfo(mod, info);
3290 /* Fix up syms, so that st_value is a pointer to location. */
3291 err = simplify_symbols(mod, info);
3292 if (err < 0)
3293 goto free_modinfo;
3295 err = apply_relocations(mod, info);
3296 if (err < 0)
3297 goto free_modinfo;
3299 err = post_relocation(mod, info);
3300 if (err < 0)
3301 goto free_modinfo;
3303 flush_module_icache(mod);
3305 /* Now copy in args */
3306 mod->args = strndup_user(uargs, ~0UL >> 1);
3307 if (IS_ERR(mod->args)) {
3308 err = PTR_ERR(mod->args);
3309 goto free_arch_cleanup;
3312 dynamic_debug_setup(info->debug, info->num_debug);
3314 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3315 ftrace_module_init(mod);
3317 /* Finally it's fully formed, ready to start executing. */
3318 err = complete_formation(mod, info);
3319 if (err)
3320 goto ddebug_cleanup;
3322 /* Module is ready to execute: parsing args may do that. */
3323 after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
3324 -32768, 32767, unknown_module_param_cb);
3325 if (IS_ERR(after_dashes)) {
3326 err = PTR_ERR(after_dashes);
3327 goto bug_cleanup;
3328 } else if (after_dashes) {
3329 pr_warn("%s: parameters '%s' after `--' ignored\n",
3330 mod->name, after_dashes);
3333 /* Link in to syfs. */
3334 err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3335 if (err < 0)
3336 goto bug_cleanup;
3338 /* Get rid of temporary copy. */
3339 free_copy(info);
3341 /* Done! */
3342 trace_module_load(mod);
3344 return do_init_module(mod);
3346 bug_cleanup:
3347 /* module_bug_cleanup needs module_mutex protection */
3348 mutex_lock(&module_mutex);
3349 module_bug_cleanup(mod);
3350 mutex_unlock(&module_mutex);
3352 /* Free lock-classes: */
3353 lockdep_free_key_range(mod->module_core, mod->core_size);
3355 /* we can't deallocate the module until we clear memory protection */
3356 unset_module_init_ro_nx(mod);
3357 unset_module_core_ro_nx(mod);
3359 ddebug_cleanup:
3360 dynamic_debug_remove(info->debug);
3361 synchronize_sched();
3362 kfree(mod->args);
3363 free_arch_cleanup:
3364 module_arch_cleanup(mod);
3365 free_modinfo:
3366 free_modinfo(mod);
3367 free_unload:
3368 module_unload_free(mod);
3369 unlink_mod:
3370 mutex_lock(&module_mutex);
3371 /* Unlink carefully: kallsyms could be walking list. */
3372 list_del_rcu(&mod->list);
3373 wake_up_all(&module_wq);
3374 /* Wait for RCU synchronizing before releasing mod->list. */
3375 synchronize_rcu();
3376 mutex_unlock(&module_mutex);
3377 free_module:
3378 module_deallocate(mod, info);
3379 free_copy:
3380 free_copy(info);
3381 return err;
3384 SYSCALL_DEFINE3(init_module, void __user *, umod,
3385 unsigned long, len, const char __user *, uargs)
3387 int err;
3388 struct load_info info = { };
3390 err = may_init_module();
3391 if (err)
3392 return err;
3394 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3395 umod, len, uargs);
3397 err = copy_module_from_user(umod, len, &info);
3398 if (err)
3399 return err;
3401 return load_module(&info, uargs, 0);
3404 SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3406 int err;
3407 struct load_info info = { };
3409 err = may_init_module();
3410 if (err)
3411 return err;
3413 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3415 if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3416 |MODULE_INIT_IGNORE_VERMAGIC))
3417 return -EINVAL;
3419 err = copy_module_from_fd(fd, &info);
3420 if (err)
3421 return err;
3423 return load_module(&info, uargs, flags);
3426 static inline int within(unsigned long addr, void *start, unsigned long size)
3428 return ((void *)addr >= start && (void *)addr < start + size);
3431 #ifdef CONFIG_KALLSYMS
3433 * This ignores the intensely annoying "mapping symbols" found
3434 * in ARM ELF files: $a, $t and $d.
3436 static inline int is_arm_mapping_symbol(const char *str)
3438 if (str[0] == '.' && str[1] == 'L')
3439 return true;
3440 return str[0] == '$' && strchr("axtd", str[1])
3441 && (str[2] == '\0' || str[2] == '.');
3444 static const char *get_ksymbol(struct module *mod,
3445 unsigned long addr,
3446 unsigned long *size,
3447 unsigned long *offset)
3449 unsigned int i, best = 0;
3450 unsigned long nextval;
3452 /* At worse, next value is at end of module */
3453 if (within_module_init(addr, mod))
3454 nextval = (unsigned long)mod->module_init+mod->init_text_size;
3455 else
3456 nextval = (unsigned long)mod->module_core+mod->core_text_size;
3458 /* Scan for closest preceding symbol, and next symbol. (ELF
3459 starts real symbols at 1). */
3460 for (i = 1; i < mod->num_symtab; i++) {
3461 if (mod->symtab[i].st_shndx == SHN_UNDEF)
3462 continue;
3464 /* We ignore unnamed symbols: they're uninformative
3465 * and inserted at a whim. */
3466 if (mod->symtab[i].st_value <= addr
3467 && mod->symtab[i].st_value > mod->symtab[best].st_value
3468 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3469 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3470 best = i;
3471 if (mod->symtab[i].st_value > addr
3472 && mod->symtab[i].st_value < nextval
3473 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3474 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3475 nextval = mod->symtab[i].st_value;
3478 if (!best)
3479 return NULL;
3481 if (size)
3482 *size = nextval - mod->symtab[best].st_value;
3483 if (offset)
3484 *offset = addr - mod->symtab[best].st_value;
3485 return mod->strtab + mod->symtab[best].st_name;
3488 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3489 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3490 const char *module_address_lookup(unsigned long addr,
3491 unsigned long *size,
3492 unsigned long *offset,
3493 char **modname,
3494 char *namebuf)
3496 struct module *mod;
3497 const char *ret = NULL;
3499 preempt_disable();
3500 list_for_each_entry_rcu(mod, &modules, list) {
3501 if (mod->state == MODULE_STATE_UNFORMED)
3502 continue;
3503 if (within_module(addr, mod)) {
3504 if (modname)
3505 *modname = mod->name;
3506 ret = get_ksymbol(mod, addr, size, offset);
3507 break;
3510 /* Make a copy in here where it's safe */
3511 if (ret) {
3512 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
3513 ret = namebuf;
3515 preempt_enable();
3516 return ret;
3519 int lookup_module_symbol_name(unsigned long addr, char *symname)
3521 struct module *mod;
3523 preempt_disable();
3524 list_for_each_entry_rcu(mod, &modules, list) {
3525 if (mod->state == MODULE_STATE_UNFORMED)
3526 continue;
3527 if (within_module(addr, mod)) {
3528 const char *sym;
3530 sym = get_ksymbol(mod, addr, NULL, NULL);
3531 if (!sym)
3532 goto out;
3533 strlcpy(symname, sym, KSYM_NAME_LEN);
3534 preempt_enable();
3535 return 0;
3538 out:
3539 preempt_enable();
3540 return -ERANGE;
3543 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
3544 unsigned long *offset, char *modname, char *name)
3546 struct module *mod;
3548 preempt_disable();
3549 list_for_each_entry_rcu(mod, &modules, list) {
3550 if (mod->state == MODULE_STATE_UNFORMED)
3551 continue;
3552 if (within_module(addr, mod)) {
3553 const char *sym;
3555 sym = get_ksymbol(mod, addr, size, offset);
3556 if (!sym)
3557 goto out;
3558 if (modname)
3559 strlcpy(modname, mod->name, MODULE_NAME_LEN);
3560 if (name)
3561 strlcpy(name, sym, KSYM_NAME_LEN);
3562 preempt_enable();
3563 return 0;
3566 out:
3567 preempt_enable();
3568 return -ERANGE;
3571 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
3572 char *name, char *module_name, int *exported)
3574 struct module *mod;
3576 preempt_disable();
3577 list_for_each_entry_rcu(mod, &modules, list) {
3578 if (mod->state == MODULE_STATE_UNFORMED)
3579 continue;
3580 if (symnum < mod->num_symtab) {
3581 *value = mod->symtab[symnum].st_value;
3582 *type = mod->symtab[symnum].st_info;
3583 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
3584 KSYM_NAME_LEN);
3585 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
3586 *exported = is_exported(name, *value, mod);
3587 preempt_enable();
3588 return 0;
3590 symnum -= mod->num_symtab;
3592 preempt_enable();
3593 return -ERANGE;
3596 static unsigned long mod_find_symname(struct module *mod, const char *name)
3598 unsigned int i;
3600 for (i = 0; i < mod->num_symtab; i++)
3601 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
3602 mod->symtab[i].st_info != 'U')
3603 return mod->symtab[i].st_value;
3604 return 0;
3607 /* Look for this name: can be of form module:name. */
3608 unsigned long module_kallsyms_lookup_name(const char *name)
3610 struct module *mod;
3611 char *colon;
3612 unsigned long ret = 0;
3614 /* Don't lock: we're in enough trouble already. */
3615 preempt_disable();
3616 if ((colon = strchr(name, ':')) != NULL) {
3617 if ((mod = find_module_all(name, colon - name, false)) != NULL)
3618 ret = mod_find_symname(mod, colon+1);
3619 } else {
3620 list_for_each_entry_rcu(mod, &modules, list) {
3621 if (mod->state == MODULE_STATE_UNFORMED)
3622 continue;
3623 if ((ret = mod_find_symname(mod, name)) != 0)
3624 break;
3627 preempt_enable();
3628 return ret;
3631 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3632 struct module *, unsigned long),
3633 void *data)
3635 struct module *mod;
3636 unsigned int i;
3637 int ret;
3639 list_for_each_entry(mod, &modules, list) {
3640 if (mod->state == MODULE_STATE_UNFORMED)
3641 continue;
3642 for (i = 0; i < mod->num_symtab; i++) {
3643 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
3644 mod, mod->symtab[i].st_value);
3645 if (ret != 0)
3646 return ret;
3649 return 0;
3651 #endif /* CONFIG_KALLSYMS */
3653 static char *module_flags(struct module *mod, char *buf)
3655 int bx = 0;
3657 BUG_ON(mod->state == MODULE_STATE_UNFORMED);
3658 if (mod->taints ||
3659 mod->state == MODULE_STATE_GOING ||
3660 mod->state == MODULE_STATE_COMING) {
3661 buf[bx++] = '(';
3662 bx += module_flags_taint(mod, buf + bx);
3663 /* Show a - for module-is-being-unloaded */
3664 if (mod->state == MODULE_STATE_GOING)
3665 buf[bx++] = '-';
3666 /* Show a + for module-is-being-loaded */
3667 if (mod->state == MODULE_STATE_COMING)
3668 buf[bx++] = '+';
3669 buf[bx++] = ')';
3671 buf[bx] = '\0';
3673 return buf;
3676 #ifdef CONFIG_PROC_FS
3677 /* Called by the /proc file system to return a list of modules. */
3678 static void *m_start(struct seq_file *m, loff_t *pos)
3680 mutex_lock(&module_mutex);
3681 return seq_list_start(&modules, *pos);
3684 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3686 return seq_list_next(p, &modules, pos);
3689 static void m_stop(struct seq_file *m, void *p)
3691 mutex_unlock(&module_mutex);
3694 static int m_show(struct seq_file *m, void *p)
3696 struct module *mod = list_entry(p, struct module, list);
3697 char buf[8];
3699 /* We always ignore unformed modules. */
3700 if (mod->state == MODULE_STATE_UNFORMED)
3701 return 0;
3703 seq_printf(m, "%s %u",
3704 mod->name, mod->init_size + mod->core_size);
3705 print_unload_info(m, mod);
3707 /* Informative for users. */
3708 seq_printf(m, " %s",
3709 mod->state == MODULE_STATE_GOING ? "Unloading" :
3710 mod->state == MODULE_STATE_COMING ? "Loading" :
3711 "Live");
3712 /* Used by oprofile and other similar tools. */
3713 seq_printf(m, " 0x%pK", mod->module_core);
3715 /* Taints info */
3716 if (mod->taints)
3717 seq_printf(m, " %s", module_flags(mod, buf));
3719 seq_puts(m, "\n");
3720 return 0;
3723 /* Format: modulename size refcount deps address
3725 Where refcount is a number or -, and deps is a comma-separated list
3726 of depends or -.
3728 static const struct seq_operations modules_op = {
3729 .start = m_start,
3730 .next = m_next,
3731 .stop = m_stop,
3732 .show = m_show
3735 static int modules_open(struct inode *inode, struct file *file)
3737 return seq_open(file, &modules_op);
3740 static const struct file_operations proc_modules_operations = {
3741 .open = modules_open,
3742 .read = seq_read,
3743 .llseek = seq_lseek,
3744 .release = seq_release,
3747 static int __init proc_modules_init(void)
3749 proc_create("modules", 0, NULL, &proc_modules_operations);
3750 return 0;
3752 module_init(proc_modules_init);
3753 #endif
3755 /* Given an address, look for it in the module exception tables. */
3756 const struct exception_table_entry *search_module_extables(unsigned long addr)
3758 const struct exception_table_entry *e = NULL;
3759 struct module *mod;
3761 preempt_disable();
3762 list_for_each_entry_rcu(mod, &modules, list) {
3763 if (mod->state == MODULE_STATE_UNFORMED)
3764 continue;
3765 if (mod->num_exentries == 0)
3766 continue;
3768 e = search_extable(mod->extable,
3769 mod->extable + mod->num_exentries - 1,
3770 addr);
3771 if (e)
3772 break;
3774 preempt_enable();
3776 /* Now, if we found one, we are running inside it now, hence
3777 we cannot unload the module, hence no refcnt needed. */
3778 return e;
3782 * is_module_address - is this address inside a module?
3783 * @addr: the address to check.
3785 * See is_module_text_address() if you simply want to see if the address
3786 * is code (not data).
3788 bool is_module_address(unsigned long addr)
3790 bool ret;
3792 preempt_disable();
3793 ret = __module_address(addr) != NULL;
3794 preempt_enable();
3796 return ret;
3800 * __module_address - get the module which contains an address.
3801 * @addr: the address.
3803 * Must be called with preempt disabled or module mutex held so that
3804 * module doesn't get freed during this.
3806 struct module *__module_address(unsigned long addr)
3808 struct module *mod;
3810 if (addr < module_addr_min || addr > module_addr_max)
3811 return NULL;
3813 list_for_each_entry_rcu(mod, &modules, list) {
3814 if (mod->state == MODULE_STATE_UNFORMED)
3815 continue;
3816 if (within_module(addr, mod))
3817 return mod;
3819 return NULL;
3821 EXPORT_SYMBOL_GPL(__module_address);
3824 * is_module_text_address - is this address inside module code?
3825 * @addr: the address to check.
3827 * See is_module_address() if you simply want to see if the address is
3828 * anywhere in a module. See kernel_text_address() for testing if an
3829 * address corresponds to kernel or module code.
3831 bool is_module_text_address(unsigned long addr)
3833 bool ret;
3835 preempt_disable();
3836 ret = __module_text_address(addr) != NULL;
3837 preempt_enable();
3839 return ret;
3843 * __module_text_address - get the module whose code contains an address.
3844 * @addr: the address.
3846 * Must be called with preempt disabled or module mutex held so that
3847 * module doesn't get freed during this.
3849 struct module *__module_text_address(unsigned long addr)
3851 struct module *mod = __module_address(addr);
3852 if (mod) {
3853 /* Make sure it's within the text section. */
3854 if (!within(addr, mod->module_init, mod->init_text_size)
3855 && !within(addr, mod->module_core, mod->core_text_size))
3856 mod = NULL;
3858 return mod;
3860 EXPORT_SYMBOL_GPL(__module_text_address);
3862 /* Don't grab lock, we're oopsing. */
3863 void print_modules(void)
3865 struct module *mod;
3866 char buf[8];
3868 printk(KERN_DEFAULT "Modules linked in:");
3869 /* Most callers should already have preempt disabled, but make sure */
3870 preempt_disable();
3871 list_for_each_entry_rcu(mod, &modules, list) {
3872 if (mod->state == MODULE_STATE_UNFORMED)
3873 continue;
3874 pr_cont(" %s%s", mod->name, module_flags(mod, buf));
3876 preempt_enable();
3877 if (last_unloaded_module[0])
3878 pr_cont(" [last unloaded: %s]", last_unloaded_module);
3879 pr_cont("\n");
3882 #ifdef CONFIG_MODVERSIONS
3883 /* Generate the signature for all relevant module structures here.
3884 * If these change, we don't want to try to parse the module. */
3885 void module_layout(struct module *mod,
3886 struct modversion_info *ver,
3887 struct kernel_param *kp,
3888 struct kernel_symbol *ks,
3889 struct tracepoint * const *tp)
3892 EXPORT_SYMBOL(module_layout);
3893 #endif