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/trace_events.h>
22 #include <linux/init.h>
23 #include <linux/kallsyms.h>
24 #include <linux/file.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/livepatch.h>
57 #include <linux/async.h>
58 #include <linux/percpu.h>
59 #include <linux/kmemleak.h>
60 #include <linux/jump_label.h>
61 #include <linux/pfn.h>
62 #include <linux/bsearch.h>
63 #include <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
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)
81 # define debug_align(X) (X)
84 /* If this is set, the section belongs in the init part of the module */
85 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
89 * 1) List of modules (also safely readable with preempt_disable),
90 * 2) module_use links,
91 * 3) module_addr_min/module_addr_max.
92 * (delete and add uses RCU list operations). */
93 DEFINE_MUTEX(module_mutex);
94 EXPORT_SYMBOL_GPL(module_mutex);
95 static LIST_HEAD(modules);
97 #ifdef CONFIG_MODULES_TREE_LOOKUP
100 * Use a latched RB-tree for __module_address(); this allows us to use
101 * RCU-sched lookups of the address from any context.
103 * This is conditional on PERF_EVENTS || TRACING because those can really hit
104 * __module_address() hard by doing a lot of stack unwinding; potentially from
108 static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
110 struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
112 return (unsigned long)layout->base;
115 static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
117 struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
119 return (unsigned long)layout->size;
122 static __always_inline bool
123 mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b)
125 return __mod_tree_val(a) < __mod_tree_val(b);
128 static __always_inline int
129 mod_tree_comp(void *key, struct latch_tree_node *n)
131 unsigned long val = (unsigned long)key;
132 unsigned long start, end;
134 start = __mod_tree_val(n);
138 end = start + __mod_tree_size(n);
145 static const struct latch_tree_ops mod_tree_ops = {
146 .less = mod_tree_less,
147 .comp = mod_tree_comp,
150 static struct mod_tree_root {
151 struct latch_tree_root root;
152 unsigned long addr_min;
153 unsigned long addr_max;
154 } mod_tree __cacheline_aligned = {
158 #define module_addr_min mod_tree.addr_min
159 #define module_addr_max mod_tree.addr_max
161 static noinline void __mod_tree_insert(struct mod_tree_node *node)
163 latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops);
166 static void __mod_tree_remove(struct mod_tree_node *node)
168 latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops);
172 * These modifications: insert, remove_init and remove; are serialized by the
175 static void mod_tree_insert(struct module *mod)
177 mod->core_layout.mtn.mod = mod;
178 mod->init_layout.mtn.mod = mod;
180 __mod_tree_insert(&mod->core_layout.mtn);
181 if (mod->init_layout.size)
182 __mod_tree_insert(&mod->init_layout.mtn);
185 static void mod_tree_remove_init(struct module *mod)
187 if (mod->init_layout.size)
188 __mod_tree_remove(&mod->init_layout.mtn);
191 static void mod_tree_remove(struct module *mod)
193 __mod_tree_remove(&mod->core_layout.mtn);
194 mod_tree_remove_init(mod);
197 static struct module *mod_find(unsigned long addr)
199 struct latch_tree_node *ltn;
201 ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops);
205 return container_of(ltn, struct mod_tree_node, node)->mod;
208 #else /* MODULES_TREE_LOOKUP */
210 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
212 static void mod_tree_insert(struct module *mod) { }
213 static void mod_tree_remove_init(struct module *mod) { }
214 static void mod_tree_remove(struct module *mod) { }
216 static struct module *mod_find(unsigned long addr)
220 list_for_each_entry_rcu(mod, &modules, list) {
221 if (within_module(addr, mod))
228 #endif /* MODULES_TREE_LOOKUP */
231 * Bounds of module text, for speeding up __module_address.
232 * Protected by module_mutex.
234 static void __mod_update_bounds(void *base, unsigned int size)
236 unsigned long min = (unsigned long)base;
237 unsigned long max = min + size;
239 if (min < module_addr_min)
240 module_addr_min = min;
241 if (max > module_addr_max)
242 module_addr_max = max;
245 static void mod_update_bounds(struct module *mod)
247 __mod_update_bounds(mod->core_layout.base, mod->core_layout.size);
248 if (mod->init_layout.size)
249 __mod_update_bounds(mod->init_layout.base, mod->init_layout.size);
252 #ifdef CONFIG_KGDB_KDB
253 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
254 #endif /* CONFIG_KGDB_KDB */
256 static void module_assert_mutex(void)
258 lockdep_assert_held(&module_mutex);
261 static void module_assert_mutex_or_preempt(void)
263 #ifdef CONFIG_LOCKDEP
264 if (unlikely(!debug_locks))
267 WARN_ON(!rcu_read_lock_sched_held() &&
268 !lockdep_is_held(&module_mutex));
272 static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE);
273 #ifndef CONFIG_MODULE_SIG_FORCE
274 module_param(sig_enforce, bool_enable_only, 0644);
275 #endif /* !CONFIG_MODULE_SIG_FORCE */
277 /* Block module loading/unloading? */
278 int modules_disabled = 0;
279 core_param(nomodule, modules_disabled, bint, 0);
281 /* Waiting for a module to finish initializing? */
282 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
284 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
286 int register_module_notifier(struct notifier_block *nb)
288 return blocking_notifier_chain_register(&module_notify_list, nb);
290 EXPORT_SYMBOL(register_module_notifier);
292 int unregister_module_notifier(struct notifier_block *nb)
294 return blocking_notifier_chain_unregister(&module_notify_list, nb);
296 EXPORT_SYMBOL(unregister_module_notifier);
302 char *secstrings, *strtab;
303 unsigned long symoffs, stroffs;
304 struct _ddebug *debug;
305 unsigned int num_debug;
307 #ifdef CONFIG_KALLSYMS
308 unsigned long mod_kallsyms_init_off;
311 unsigned int sym, str, mod, vers, info, pcpu;
315 /* We require a truly strong try_module_get(): 0 means failure due to
316 ongoing or failed initialization etc. */
317 static inline int strong_try_module_get(struct module *mod)
319 BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
320 if (mod && mod->state == MODULE_STATE_COMING)
322 if (try_module_get(mod))
328 static inline void add_taint_module(struct module *mod, unsigned flag,
329 enum lockdep_ok lockdep_ok)
331 add_taint(flag, lockdep_ok);
332 mod->taints |= (1U << flag);
336 * A thread that wants to hold a reference to a module only while it
337 * is running can call this to safely exit. nfsd and lockd use this.
339 void __module_put_and_exit(struct module *mod, long code)
344 EXPORT_SYMBOL(__module_put_and_exit);
346 /* Find a module section: 0 means not found. */
347 static unsigned int find_sec(const struct load_info *info, const char *name)
351 for (i = 1; i < info->hdr->e_shnum; i++) {
352 Elf_Shdr *shdr = &info->sechdrs[i];
353 /* Alloc bit cleared means "ignore it." */
354 if ((shdr->sh_flags & SHF_ALLOC)
355 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
361 /* Find a module section, or NULL. */
362 static void *section_addr(const struct load_info *info, const char *name)
364 /* Section 0 has sh_addr 0. */
365 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
368 /* Find a module section, or NULL. Fill in number of "objects" in section. */
369 static void *section_objs(const struct load_info *info,
374 unsigned int sec = find_sec(info, name);
376 /* Section 0 has sh_addr 0 and sh_size 0. */
377 *num = info->sechdrs[sec].sh_size / object_size;
378 return (void *)info->sechdrs[sec].sh_addr;
381 /* Provided by the linker */
382 extern const struct kernel_symbol __start___ksymtab[];
383 extern const struct kernel_symbol __stop___ksymtab[];
384 extern const struct kernel_symbol __start___ksymtab_gpl[];
385 extern const struct kernel_symbol __stop___ksymtab_gpl[];
386 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
387 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
388 extern const unsigned long __start___kcrctab[];
389 extern const unsigned long __start___kcrctab_gpl[];
390 extern const unsigned long __start___kcrctab_gpl_future[];
391 #ifdef CONFIG_UNUSED_SYMBOLS
392 extern const struct kernel_symbol __start___ksymtab_unused[];
393 extern const struct kernel_symbol __stop___ksymtab_unused[];
394 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
395 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
396 extern const unsigned long __start___kcrctab_unused[];
397 extern const unsigned long __start___kcrctab_unused_gpl[];
400 #ifndef CONFIG_MODVERSIONS
401 #define symversion(base, idx) NULL
403 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
406 static bool each_symbol_in_section(const struct symsearch *arr,
407 unsigned int arrsize,
408 struct module *owner,
409 bool (*fn)(const struct symsearch *syms,
410 struct module *owner,
416 for (j = 0; j < arrsize; j++) {
417 if (fn(&arr[j], owner, data))
424 /* Returns true as soon as fn returns true, otherwise false. */
425 bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
426 struct module *owner,
431 static const struct symsearch arr[] = {
432 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
433 NOT_GPL_ONLY, false },
434 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
435 __start___kcrctab_gpl,
437 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
438 __start___kcrctab_gpl_future,
439 WILL_BE_GPL_ONLY, false },
440 #ifdef CONFIG_UNUSED_SYMBOLS
441 { __start___ksymtab_unused, __stop___ksymtab_unused,
442 __start___kcrctab_unused,
443 NOT_GPL_ONLY, true },
444 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
445 __start___kcrctab_unused_gpl,
450 module_assert_mutex_or_preempt();
452 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
455 list_for_each_entry_rcu(mod, &modules, list) {
456 struct symsearch arr[] = {
457 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
458 NOT_GPL_ONLY, false },
459 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
462 { mod->gpl_future_syms,
463 mod->gpl_future_syms + mod->num_gpl_future_syms,
464 mod->gpl_future_crcs,
465 WILL_BE_GPL_ONLY, false },
466 #ifdef CONFIG_UNUSED_SYMBOLS
468 mod->unused_syms + mod->num_unused_syms,
470 NOT_GPL_ONLY, true },
471 { mod->unused_gpl_syms,
472 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
473 mod->unused_gpl_crcs,
478 if (mod->state == MODULE_STATE_UNFORMED)
481 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
486 EXPORT_SYMBOL_GPL(each_symbol_section);
488 struct find_symbol_arg {
495 struct module *owner;
496 const unsigned long *crc;
497 const struct kernel_symbol *sym;
500 static bool check_symbol(const struct symsearch *syms,
501 struct module *owner,
502 unsigned int symnum, void *data)
504 struct find_symbol_arg *fsa = data;
507 if (syms->licence == GPL_ONLY)
509 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
510 pr_warn("Symbol %s is being used by a non-GPL module, "
511 "which will not be allowed in the future\n",
516 #ifdef CONFIG_UNUSED_SYMBOLS
517 if (syms->unused && fsa->warn) {
518 pr_warn("Symbol %s is marked as UNUSED, however this module is "
519 "using it.\n", fsa->name);
520 pr_warn("This symbol will go away in the future.\n");
521 pr_warn("Please evaluate if this is the right api to use and "
522 "if it really is, submit a report to the linux kernel "
523 "mailing list together with submitting your code for "
529 fsa->crc = symversion(syms->crcs, symnum);
530 fsa->sym = &syms->start[symnum];
534 static int cmp_name(const void *va, const void *vb)
537 const struct kernel_symbol *b;
539 return strcmp(a, b->name);
542 static bool find_symbol_in_section(const struct symsearch *syms,
543 struct module *owner,
546 struct find_symbol_arg *fsa = data;
547 struct kernel_symbol *sym;
549 sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
550 sizeof(struct kernel_symbol), cmp_name);
552 if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
558 /* Find a symbol and return it, along with, (optional) crc and
559 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
560 const struct kernel_symbol *find_symbol(const char *name,
561 struct module **owner,
562 const unsigned long **crc,
566 struct find_symbol_arg fsa;
572 if (each_symbol_section(find_symbol_in_section, &fsa)) {
580 pr_debug("Failed to find symbol %s\n", name);
583 EXPORT_SYMBOL_GPL(find_symbol);
586 * Search for module by name: must hold module_mutex (or preempt disabled
587 * for read-only access).
589 static struct module *find_module_all(const char *name, size_t len,
594 module_assert_mutex_or_preempt();
596 list_for_each_entry(mod, &modules, list) {
597 if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
599 if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
605 struct module *find_module(const char *name)
607 module_assert_mutex();
608 return find_module_all(name, strlen(name), false);
610 EXPORT_SYMBOL_GPL(find_module);
614 static inline void __percpu *mod_percpu(struct module *mod)
619 static int percpu_modalloc(struct module *mod, struct load_info *info)
621 Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
622 unsigned long align = pcpusec->sh_addralign;
624 if (!pcpusec->sh_size)
627 if (align > PAGE_SIZE) {
628 pr_warn("%s: per-cpu alignment %li > %li\n",
629 mod->name, align, PAGE_SIZE);
633 mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
635 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
636 mod->name, (unsigned long)pcpusec->sh_size);
639 mod->percpu_size = pcpusec->sh_size;
643 static void percpu_modfree(struct module *mod)
645 free_percpu(mod->percpu);
648 static unsigned int find_pcpusec(struct load_info *info)
650 return find_sec(info, ".data..percpu");
653 static void percpu_modcopy(struct module *mod,
654 const void *from, unsigned long size)
658 for_each_possible_cpu(cpu)
659 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
663 * is_module_percpu_address - test whether address is from module static percpu
664 * @addr: address to test
666 * Test whether @addr belongs to module static percpu area.
669 * %true if @addr is from module static percpu area
671 bool is_module_percpu_address(unsigned long addr)
678 list_for_each_entry_rcu(mod, &modules, list) {
679 if (mod->state == MODULE_STATE_UNFORMED)
681 if (!mod->percpu_size)
683 for_each_possible_cpu(cpu) {
684 void *start = per_cpu_ptr(mod->percpu, cpu);
686 if ((void *)addr >= start &&
687 (void *)addr < start + mod->percpu_size) {
698 #else /* ... !CONFIG_SMP */
700 static inline void __percpu *mod_percpu(struct module *mod)
704 static int percpu_modalloc(struct module *mod, struct load_info *info)
706 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
707 if (info->sechdrs[info->index.pcpu].sh_size != 0)
711 static inline void percpu_modfree(struct module *mod)
714 static unsigned int find_pcpusec(struct load_info *info)
718 static inline void percpu_modcopy(struct module *mod,
719 const void *from, unsigned long size)
721 /* pcpusec should be 0, and size of that section should be 0. */
724 bool is_module_percpu_address(unsigned long addr)
729 #endif /* CONFIG_SMP */
731 #define MODINFO_ATTR(field) \
732 static void setup_modinfo_##field(struct module *mod, const char *s) \
734 mod->field = kstrdup(s, GFP_KERNEL); \
736 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
737 struct module_kobject *mk, char *buffer) \
739 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
741 static int modinfo_##field##_exists(struct module *mod) \
743 return mod->field != NULL; \
745 static void free_modinfo_##field(struct module *mod) \
750 static struct module_attribute modinfo_##field = { \
751 .attr = { .name = __stringify(field), .mode = 0444 }, \
752 .show = show_modinfo_##field, \
753 .setup = setup_modinfo_##field, \
754 .test = modinfo_##field##_exists, \
755 .free = free_modinfo_##field, \
758 MODINFO_ATTR(version);
759 MODINFO_ATTR(srcversion);
761 static char last_unloaded_module[MODULE_NAME_LEN+1];
763 #ifdef CONFIG_MODULE_UNLOAD
765 EXPORT_TRACEPOINT_SYMBOL(module_get);
767 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
768 #define MODULE_REF_BASE 1
770 /* Init the unload section of the module. */
771 static int module_unload_init(struct module *mod)
774 * Initialize reference counter to MODULE_REF_BASE.
775 * refcnt == 0 means module is going.
777 atomic_set(&mod->refcnt, MODULE_REF_BASE);
779 INIT_LIST_HEAD(&mod->source_list);
780 INIT_LIST_HEAD(&mod->target_list);
782 /* Hold reference count during initialization. */
783 atomic_inc(&mod->refcnt);
788 /* Does a already use b? */
789 static int already_uses(struct module *a, struct module *b)
791 struct module_use *use;
793 list_for_each_entry(use, &b->source_list, source_list) {
794 if (use->source == a) {
795 pr_debug("%s uses %s!\n", a->name, b->name);
799 pr_debug("%s does not use %s!\n", a->name, b->name);
805 * - we add 'a' as a "source", 'b' as a "target" of module use
806 * - the module_use is added to the list of 'b' sources (so
807 * 'b' can walk the list to see who sourced them), and of 'a'
808 * targets (so 'a' can see what modules it targets).
810 static int add_module_usage(struct module *a, struct module *b)
812 struct module_use *use;
814 pr_debug("Allocating new usage for %s.\n", a->name);
815 use = kmalloc(sizeof(*use), GFP_ATOMIC);
817 pr_warn("%s: out of memory loading\n", a->name);
823 list_add(&use->source_list, &b->source_list);
824 list_add(&use->target_list, &a->target_list);
828 /* Module a uses b: caller needs module_mutex() */
829 int ref_module(struct module *a, struct module *b)
833 if (b == NULL || already_uses(a, b))
836 /* If module isn't available, we fail. */
837 err = strong_try_module_get(b);
841 err = add_module_usage(a, b);
848 EXPORT_SYMBOL_GPL(ref_module);
850 /* Clear the unload stuff of the module. */
851 static void module_unload_free(struct module *mod)
853 struct module_use *use, *tmp;
855 mutex_lock(&module_mutex);
856 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
857 struct module *i = use->target;
858 pr_debug("%s unusing %s\n", mod->name, i->name);
860 list_del(&use->source_list);
861 list_del(&use->target_list);
864 mutex_unlock(&module_mutex);
867 #ifdef CONFIG_MODULE_FORCE_UNLOAD
868 static inline int try_force_unload(unsigned int flags)
870 int ret = (flags & O_TRUNC);
872 add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
876 static inline int try_force_unload(unsigned int flags)
880 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
882 /* Try to release refcount of module, 0 means success. */
883 static int try_release_module_ref(struct module *mod)
887 /* Try to decrement refcnt which we set at loading */
888 ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
891 /* Someone can put this right now, recover with checking */
892 ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
897 static int try_stop_module(struct module *mod, int flags, int *forced)
899 /* If it's not unused, quit unless we're forcing. */
900 if (try_release_module_ref(mod) != 0) {
901 *forced = try_force_unload(flags);
906 /* Mark it as dying. */
907 mod->state = MODULE_STATE_GOING;
913 * module_refcount - return the refcount or -1 if unloading
915 * @mod: the module we're checking
918 * -1 if the module is in the process of unloading
919 * otherwise the number of references in the kernel to the module
921 int module_refcount(struct module *mod)
923 return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
925 EXPORT_SYMBOL(module_refcount);
927 /* This exists whether we can unload or not */
928 static void free_module(struct module *mod);
930 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
934 char name[MODULE_NAME_LEN];
937 if (!capable(CAP_SYS_MODULE) || modules_disabled)
940 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
942 name[MODULE_NAME_LEN-1] = '\0';
944 if (mutex_lock_interruptible(&module_mutex) != 0)
947 mod = find_module(name);
953 if (!list_empty(&mod->source_list)) {
954 /* Other modules depend on us: get rid of them first. */
959 /* Doing init or already dying? */
960 if (mod->state != MODULE_STATE_LIVE) {
961 /* FIXME: if (force), slam module count damn the torpedoes */
962 pr_debug("%s already dying\n", mod->name);
967 /* If it has an init func, it must have an exit func to unload */
968 if (mod->init && !mod->exit) {
969 forced = try_force_unload(flags);
971 /* This module can't be removed */
977 /* Stop the machine so refcounts can't move and disable module. */
978 ret = try_stop_module(mod, flags, &forced);
982 mutex_unlock(&module_mutex);
983 /* Final destruction now no one is using it. */
984 if (mod->exit != NULL)
986 blocking_notifier_call_chain(&module_notify_list,
987 MODULE_STATE_GOING, mod);
988 klp_module_going(mod);
989 ftrace_release_mod(mod);
991 async_synchronize_full();
993 /* Store the name of the last unloaded module for diagnostic purposes */
994 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
999 mutex_unlock(&module_mutex);
1003 static inline void print_unload_info(struct seq_file *m, struct module *mod)
1005 struct module_use *use;
1006 int printed_something = 0;
1008 seq_printf(m, " %i ", module_refcount(mod));
1011 * Always include a trailing , so userspace can differentiate
1012 * between this and the old multi-field proc format.
1014 list_for_each_entry(use, &mod->source_list, source_list) {
1015 printed_something = 1;
1016 seq_printf(m, "%s,", use->source->name);
1019 if (mod->init != NULL && mod->exit == NULL) {
1020 printed_something = 1;
1021 seq_puts(m, "[permanent],");
1024 if (!printed_something)
1028 void __symbol_put(const char *symbol)
1030 struct module *owner;
1033 if (!find_symbol(symbol, &owner, NULL, true, false))
1038 EXPORT_SYMBOL(__symbol_put);
1040 /* Note this assumes addr is a function, which it currently always is. */
1041 void symbol_put_addr(void *addr)
1043 struct module *modaddr;
1044 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
1046 if (core_kernel_text(a))
1050 * Even though we hold a reference on the module; we still need to
1051 * disable preemption in order to safely traverse the data structure.
1054 modaddr = __module_text_address(a);
1056 module_put(modaddr);
1059 EXPORT_SYMBOL_GPL(symbol_put_addr);
1061 static ssize_t show_refcnt(struct module_attribute *mattr,
1062 struct module_kobject *mk, char *buffer)
1064 return sprintf(buffer, "%i\n", module_refcount(mk->mod));
1067 static struct module_attribute modinfo_refcnt =
1068 __ATTR(refcnt, 0444, show_refcnt, NULL);
1070 void __module_get(struct module *module)
1074 atomic_inc(&module->refcnt);
1075 trace_module_get(module, _RET_IP_);
1079 EXPORT_SYMBOL(__module_get);
1081 bool try_module_get(struct module *module)
1087 /* Note: here, we can fail to get a reference */
1088 if (likely(module_is_live(module) &&
1089 atomic_inc_not_zero(&module->refcnt) != 0))
1090 trace_module_get(module, _RET_IP_);
1098 EXPORT_SYMBOL(try_module_get);
1100 void module_put(struct module *module)
1106 ret = atomic_dec_if_positive(&module->refcnt);
1107 WARN_ON(ret < 0); /* Failed to put refcount */
1108 trace_module_put(module, _RET_IP_);
1112 EXPORT_SYMBOL(module_put);
1114 #else /* !CONFIG_MODULE_UNLOAD */
1115 static inline void print_unload_info(struct seq_file *m, struct module *mod)
1117 /* We don't know the usage count, or what modules are using. */
1118 seq_puts(m, " - -");
1121 static inline void module_unload_free(struct module *mod)
1125 int ref_module(struct module *a, struct module *b)
1127 return strong_try_module_get(b);
1129 EXPORT_SYMBOL_GPL(ref_module);
1131 static inline int module_unload_init(struct module *mod)
1135 #endif /* CONFIG_MODULE_UNLOAD */
1137 static size_t module_flags_taint(struct module *mod, char *buf)
1141 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
1143 if (mod->taints & (1 << TAINT_OOT_MODULE))
1145 if (mod->taints & (1 << TAINT_FORCED_MODULE))
1147 if (mod->taints & (1 << TAINT_CRAP))
1149 if (mod->taints & (1 << TAINT_UNSIGNED_MODULE))
1152 * TAINT_FORCED_RMMOD: could be added.
1153 * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
1159 static ssize_t show_initstate(struct module_attribute *mattr,
1160 struct module_kobject *mk, char *buffer)
1162 const char *state = "unknown";
1164 switch (mk->mod->state) {
1165 case MODULE_STATE_LIVE:
1168 case MODULE_STATE_COMING:
1171 case MODULE_STATE_GOING:
1177 return sprintf(buffer, "%s\n", state);
1180 static struct module_attribute modinfo_initstate =
1181 __ATTR(initstate, 0444, show_initstate, NULL);
1183 static ssize_t store_uevent(struct module_attribute *mattr,
1184 struct module_kobject *mk,
1185 const char *buffer, size_t count)
1187 enum kobject_action action;
1189 if (kobject_action_type(buffer, count, &action) == 0)
1190 kobject_uevent(&mk->kobj, action);
1194 struct module_attribute module_uevent =
1195 __ATTR(uevent, 0200, NULL, store_uevent);
1197 static ssize_t show_coresize(struct module_attribute *mattr,
1198 struct module_kobject *mk, char *buffer)
1200 return sprintf(buffer, "%u\n", mk->mod->core_layout.size);
1203 static struct module_attribute modinfo_coresize =
1204 __ATTR(coresize, 0444, show_coresize, NULL);
1206 static ssize_t show_initsize(struct module_attribute *mattr,
1207 struct module_kobject *mk, char *buffer)
1209 return sprintf(buffer, "%u\n", mk->mod->init_layout.size);
1212 static struct module_attribute modinfo_initsize =
1213 __ATTR(initsize, 0444, show_initsize, NULL);
1215 static ssize_t show_taint(struct module_attribute *mattr,
1216 struct module_kobject *mk, char *buffer)
1220 l = module_flags_taint(mk->mod, buffer);
1225 static struct module_attribute modinfo_taint =
1226 __ATTR(taint, 0444, show_taint, NULL);
1228 static struct module_attribute *modinfo_attrs[] = {
1231 &modinfo_srcversion,
1236 #ifdef CONFIG_MODULE_UNLOAD
1242 static const char vermagic[] = VERMAGIC_STRING;
1244 static int try_to_force_load(struct module *mod, const char *reason)
1246 #ifdef CONFIG_MODULE_FORCE_LOAD
1247 if (!test_taint(TAINT_FORCED_MODULE))
1248 pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
1249 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
1256 #ifdef CONFIG_MODVERSIONS
1257 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
1258 static unsigned long maybe_relocated(unsigned long crc,
1259 const struct module *crc_owner)
1261 #ifdef ARCH_RELOCATES_KCRCTAB
1262 if (crc_owner == NULL)
1263 return crc - (unsigned long)reloc_start;
1268 static int check_version(Elf_Shdr *sechdrs,
1269 unsigned int versindex,
1270 const char *symname,
1272 const unsigned long *crc,
1273 const struct module *crc_owner)
1275 unsigned int i, num_versions;
1276 struct modversion_info *versions;
1278 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1282 /* No versions at all? modprobe --force does this. */
1284 return try_to_force_load(mod, symname) == 0;
1286 versions = (void *) sechdrs[versindex].sh_addr;
1287 num_versions = sechdrs[versindex].sh_size
1288 / sizeof(struct modversion_info);
1290 for (i = 0; i < num_versions; i++) {
1291 if (strcmp(versions[i].name, symname) != 0)
1294 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
1296 pr_debug("Found checksum %lX vs module %lX\n",
1297 maybe_relocated(*crc, crc_owner), versions[i].crc);
1301 pr_warn("%s: no symbol version for %s\n", mod->name, symname);
1305 pr_warn("%s: disagrees about version of symbol %s\n",
1306 mod->name, symname);
1310 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1311 unsigned int versindex,
1314 const unsigned long *crc;
1317 * Since this should be found in kernel (which can't be removed), no
1318 * locking is necessary -- use preempt_disable() to placate lockdep.
1321 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
1322 &crc, true, false)) {
1327 return check_version(sechdrs, versindex,
1328 VMLINUX_SYMBOL_STR(module_layout), mod, crc,
1332 /* First part is kernel version, which we ignore if module has crcs. */
1333 static inline int same_magic(const char *amagic, const char *bmagic,
1337 amagic += strcspn(amagic, " ");
1338 bmagic += strcspn(bmagic, " ");
1340 return strcmp(amagic, bmagic) == 0;
1343 static inline int check_version(Elf_Shdr *sechdrs,
1344 unsigned int versindex,
1345 const char *symname,
1347 const unsigned long *crc,
1348 const struct module *crc_owner)
1353 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1354 unsigned int versindex,
1360 static inline int same_magic(const char *amagic, const char *bmagic,
1363 return strcmp(amagic, bmagic) == 0;
1365 #endif /* CONFIG_MODVERSIONS */
1367 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1368 static const struct kernel_symbol *resolve_symbol(struct module *mod,
1369 const struct load_info *info,
1373 struct module *owner;
1374 const struct kernel_symbol *sym;
1375 const unsigned long *crc;
1379 * The module_mutex should not be a heavily contended lock;
1380 * if we get the occasional sleep here, we'll go an extra iteration
1381 * in the wait_event_interruptible(), which is harmless.
1383 sched_annotate_sleep();
1384 mutex_lock(&module_mutex);
1385 sym = find_symbol(name, &owner, &crc,
1386 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1390 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1392 sym = ERR_PTR(-EINVAL);
1396 err = ref_module(mod, owner);
1403 /* We must make copy under the lock if we failed to get ref. */
1404 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1406 mutex_unlock(&module_mutex);
1410 static const struct kernel_symbol *
1411 resolve_symbol_wait(struct module *mod,
1412 const struct load_info *info,
1415 const struct kernel_symbol *ksym;
1416 char owner[MODULE_NAME_LEN];
1418 if (wait_event_interruptible_timeout(module_wq,
1419 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1420 || PTR_ERR(ksym) != -EBUSY,
1422 pr_warn("%s: gave up waiting for init of module %s.\n",
1429 * /sys/module/foo/sections stuff
1430 * J. Corbet <corbet@lwn.net>
1434 #ifdef CONFIG_KALLSYMS
1435 static inline bool sect_empty(const Elf_Shdr *sect)
1437 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1440 struct module_sect_attr {
1441 struct module_attribute mattr;
1443 unsigned long address;
1446 struct module_sect_attrs {
1447 struct attribute_group grp;
1448 unsigned int nsections;
1449 struct module_sect_attr attrs[0];
1452 static ssize_t module_sect_show(struct module_attribute *mattr,
1453 struct module_kobject *mk, char *buf)
1455 struct module_sect_attr *sattr =
1456 container_of(mattr, struct module_sect_attr, mattr);
1457 return sprintf(buf, "0x%pK\n", (void *)sattr->address);
1460 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1462 unsigned int section;
1464 for (section = 0; section < sect_attrs->nsections; section++)
1465 kfree(sect_attrs->attrs[section].name);
1469 static void add_sect_attrs(struct module *mod, const struct load_info *info)
1471 unsigned int nloaded = 0, i, size[2];
1472 struct module_sect_attrs *sect_attrs;
1473 struct module_sect_attr *sattr;
1474 struct attribute **gattr;
1476 /* Count loaded sections and allocate structures */
1477 for (i = 0; i < info->hdr->e_shnum; i++)
1478 if (!sect_empty(&info->sechdrs[i]))
1480 size[0] = ALIGN(sizeof(*sect_attrs)
1481 + nloaded * sizeof(sect_attrs->attrs[0]),
1482 sizeof(sect_attrs->grp.attrs[0]));
1483 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1484 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1485 if (sect_attrs == NULL)
1488 /* Setup section attributes. */
1489 sect_attrs->grp.name = "sections";
1490 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1492 sect_attrs->nsections = 0;
1493 sattr = §_attrs->attrs[0];
1494 gattr = §_attrs->grp.attrs[0];
1495 for (i = 0; i < info->hdr->e_shnum; i++) {
1496 Elf_Shdr *sec = &info->sechdrs[i];
1497 if (sect_empty(sec))
1499 sattr->address = sec->sh_addr;
1500 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1502 if (sattr->name == NULL)
1504 sect_attrs->nsections++;
1505 sysfs_attr_init(&sattr->mattr.attr);
1506 sattr->mattr.show = module_sect_show;
1507 sattr->mattr.store = NULL;
1508 sattr->mattr.attr.name = sattr->name;
1509 sattr->mattr.attr.mode = S_IRUGO;
1510 *(gattr++) = &(sattr++)->mattr.attr;
1514 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1517 mod->sect_attrs = sect_attrs;
1520 free_sect_attrs(sect_attrs);
1523 static void remove_sect_attrs(struct module *mod)
1525 if (mod->sect_attrs) {
1526 sysfs_remove_group(&mod->mkobj.kobj,
1527 &mod->sect_attrs->grp);
1528 /* We are positive that no one is using any sect attrs
1529 * at this point. Deallocate immediately. */
1530 free_sect_attrs(mod->sect_attrs);
1531 mod->sect_attrs = NULL;
1536 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1539 struct module_notes_attrs {
1540 struct kobject *dir;
1542 struct bin_attribute attrs[0];
1545 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1546 struct bin_attribute *bin_attr,
1547 char *buf, loff_t pos, size_t count)
1550 * The caller checked the pos and count against our size.
1552 memcpy(buf, bin_attr->private + pos, count);
1556 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1559 if (notes_attrs->dir) {
1561 sysfs_remove_bin_file(notes_attrs->dir,
1562 ¬es_attrs->attrs[i]);
1563 kobject_put(notes_attrs->dir);
1568 static void add_notes_attrs(struct module *mod, const struct load_info *info)
1570 unsigned int notes, loaded, i;
1571 struct module_notes_attrs *notes_attrs;
1572 struct bin_attribute *nattr;
1574 /* failed to create section attributes, so can't create notes */
1575 if (!mod->sect_attrs)
1578 /* Count notes sections and allocate structures. */
1580 for (i = 0; i < info->hdr->e_shnum; i++)
1581 if (!sect_empty(&info->sechdrs[i]) &&
1582 (info->sechdrs[i].sh_type == SHT_NOTE))
1588 notes_attrs = kzalloc(sizeof(*notes_attrs)
1589 + notes * sizeof(notes_attrs->attrs[0]),
1591 if (notes_attrs == NULL)
1594 notes_attrs->notes = notes;
1595 nattr = ¬es_attrs->attrs[0];
1596 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1597 if (sect_empty(&info->sechdrs[i]))
1599 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1600 sysfs_bin_attr_init(nattr);
1601 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1602 nattr->attr.mode = S_IRUGO;
1603 nattr->size = info->sechdrs[i].sh_size;
1604 nattr->private = (void *) info->sechdrs[i].sh_addr;
1605 nattr->read = module_notes_read;
1611 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1612 if (!notes_attrs->dir)
1615 for (i = 0; i < notes; ++i)
1616 if (sysfs_create_bin_file(notes_attrs->dir,
1617 ¬es_attrs->attrs[i]))
1620 mod->notes_attrs = notes_attrs;
1624 free_notes_attrs(notes_attrs, i);
1627 static void remove_notes_attrs(struct module *mod)
1629 if (mod->notes_attrs)
1630 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1635 static inline void add_sect_attrs(struct module *mod,
1636 const struct load_info *info)
1640 static inline void remove_sect_attrs(struct module *mod)
1644 static inline void add_notes_attrs(struct module *mod,
1645 const struct load_info *info)
1649 static inline void remove_notes_attrs(struct module *mod)
1652 #endif /* CONFIG_KALLSYMS */
1654 static void add_usage_links(struct module *mod)
1656 #ifdef CONFIG_MODULE_UNLOAD
1657 struct module_use *use;
1660 mutex_lock(&module_mutex);
1661 list_for_each_entry(use, &mod->target_list, target_list) {
1662 nowarn = sysfs_create_link(use->target->holders_dir,
1663 &mod->mkobj.kobj, mod->name);
1665 mutex_unlock(&module_mutex);
1669 static void del_usage_links(struct module *mod)
1671 #ifdef CONFIG_MODULE_UNLOAD
1672 struct module_use *use;
1674 mutex_lock(&module_mutex);
1675 list_for_each_entry(use, &mod->target_list, target_list)
1676 sysfs_remove_link(use->target->holders_dir, mod->name);
1677 mutex_unlock(&module_mutex);
1681 static int module_add_modinfo_attrs(struct module *mod)
1683 struct module_attribute *attr;
1684 struct module_attribute *temp_attr;
1688 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1689 (ARRAY_SIZE(modinfo_attrs) + 1)),
1691 if (!mod->modinfo_attrs)
1694 temp_attr = mod->modinfo_attrs;
1695 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1697 (attr->test && attr->test(mod))) {
1698 memcpy(temp_attr, attr, sizeof(*temp_attr));
1699 sysfs_attr_init(&temp_attr->attr);
1700 error = sysfs_create_file(&mod->mkobj.kobj,
1708 static void module_remove_modinfo_attrs(struct module *mod)
1710 struct module_attribute *attr;
1713 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1714 /* pick a field to test for end of list */
1715 if (!attr->attr.name)
1717 sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
1721 kfree(mod->modinfo_attrs);
1724 static void mod_kobject_put(struct module *mod)
1726 DECLARE_COMPLETION_ONSTACK(c);
1727 mod->mkobj.kobj_completion = &c;
1728 kobject_put(&mod->mkobj.kobj);
1729 wait_for_completion(&c);
1732 static int mod_sysfs_init(struct module *mod)
1735 struct kobject *kobj;
1737 if (!module_sysfs_initialized) {
1738 pr_err("%s: module sysfs not initialized\n", mod->name);
1743 kobj = kset_find_obj(module_kset, mod->name);
1745 pr_err("%s: module is already loaded\n", mod->name);
1751 mod->mkobj.mod = mod;
1753 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1754 mod->mkobj.kobj.kset = module_kset;
1755 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1758 mod_kobject_put(mod);
1760 /* delay uevent until full sysfs population */
1765 static int mod_sysfs_setup(struct module *mod,
1766 const struct load_info *info,
1767 struct kernel_param *kparam,
1768 unsigned int num_params)
1772 err = mod_sysfs_init(mod);
1776 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1777 if (!mod->holders_dir) {
1782 err = module_param_sysfs_setup(mod, kparam, num_params);
1784 goto out_unreg_holders;
1786 err = module_add_modinfo_attrs(mod);
1788 goto out_unreg_param;
1790 add_usage_links(mod);
1791 add_sect_attrs(mod, info);
1792 add_notes_attrs(mod, info);
1794 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1798 module_param_sysfs_remove(mod);
1800 kobject_put(mod->holders_dir);
1802 mod_kobject_put(mod);
1807 static void mod_sysfs_fini(struct module *mod)
1809 remove_notes_attrs(mod);
1810 remove_sect_attrs(mod);
1811 mod_kobject_put(mod);
1814 static void init_param_lock(struct module *mod)
1816 mutex_init(&mod->param_lock);
1818 #else /* !CONFIG_SYSFS */
1820 static int mod_sysfs_setup(struct module *mod,
1821 const struct load_info *info,
1822 struct kernel_param *kparam,
1823 unsigned int num_params)
1828 static void mod_sysfs_fini(struct module *mod)
1832 static void module_remove_modinfo_attrs(struct module *mod)
1836 static void del_usage_links(struct module *mod)
1840 static void init_param_lock(struct module *mod)
1843 #endif /* CONFIG_SYSFS */
1845 static void mod_sysfs_teardown(struct module *mod)
1847 del_usage_links(mod);
1848 module_remove_modinfo_attrs(mod);
1849 module_param_sysfs_remove(mod);
1850 kobject_put(mod->mkobj.drivers_dir);
1851 kobject_put(mod->holders_dir);
1852 mod_sysfs_fini(mod);
1855 #ifdef CONFIG_DEBUG_SET_MODULE_RONX
1857 * LKM RO/NX protection: protect module's text/ro-data
1858 * from modification and any data from execution.
1860 * General layout of module is:
1861 * [text] [read-only-data] [writable data]
1862 * text_size -----^ ^ ^
1863 * ro_size ------------------------| |
1864 * size -------------------------------------------|
1866 * These values are always page-aligned (as is base)
1868 static void frob_text(const struct module_layout *layout,
1869 int (*set_memory)(unsigned long start, int num_pages))
1871 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1872 BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
1873 set_memory((unsigned long)layout->base,
1874 layout->text_size >> PAGE_SHIFT);
1877 static void frob_rodata(const struct module_layout *layout,
1878 int (*set_memory)(unsigned long start, int num_pages))
1880 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1881 BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
1882 BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
1883 set_memory((unsigned long)layout->base + layout->text_size,
1884 (layout->ro_size - layout->text_size) >> PAGE_SHIFT);
1887 static void frob_writable_data(const struct module_layout *layout,
1888 int (*set_memory)(unsigned long start, int num_pages))
1890 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1891 BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
1892 BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1));
1893 set_memory((unsigned long)layout->base + layout->ro_size,
1894 (layout->size - layout->ro_size) >> PAGE_SHIFT);
1897 /* livepatching wants to disable read-only so it can frob module. */
1898 void module_disable_ro(const struct module *mod)
1900 frob_text(&mod->core_layout, set_memory_rw);
1901 frob_rodata(&mod->core_layout, set_memory_rw);
1902 frob_text(&mod->init_layout, set_memory_rw);
1903 frob_rodata(&mod->init_layout, set_memory_rw);
1906 void module_enable_ro(const struct module *mod)
1908 frob_text(&mod->core_layout, set_memory_ro);
1909 frob_rodata(&mod->core_layout, set_memory_ro);
1910 frob_text(&mod->init_layout, set_memory_ro);
1911 frob_rodata(&mod->init_layout, set_memory_ro);
1914 static void module_enable_nx(const struct module *mod)
1916 frob_rodata(&mod->core_layout, set_memory_nx);
1917 frob_writable_data(&mod->core_layout, set_memory_nx);
1918 frob_rodata(&mod->init_layout, set_memory_nx);
1919 frob_writable_data(&mod->init_layout, set_memory_nx);
1922 static void module_disable_nx(const struct module *mod)
1924 frob_rodata(&mod->core_layout, set_memory_x);
1925 frob_writable_data(&mod->core_layout, set_memory_x);
1926 frob_rodata(&mod->init_layout, set_memory_x);
1927 frob_writable_data(&mod->init_layout, set_memory_x);
1930 /* Iterate through all modules and set each module's text as RW */
1931 void set_all_modules_text_rw(void)
1935 mutex_lock(&module_mutex);
1936 list_for_each_entry_rcu(mod, &modules, list) {
1937 if (mod->state == MODULE_STATE_UNFORMED)
1940 frob_text(&mod->core_layout, set_memory_rw);
1941 frob_text(&mod->init_layout, set_memory_rw);
1943 mutex_unlock(&module_mutex);
1946 /* Iterate through all modules and set each module's text as RO */
1947 void set_all_modules_text_ro(void)
1951 mutex_lock(&module_mutex);
1952 list_for_each_entry_rcu(mod, &modules, list) {
1953 if (mod->state == MODULE_STATE_UNFORMED)
1956 frob_text(&mod->core_layout, set_memory_ro);
1957 frob_text(&mod->init_layout, set_memory_ro);
1959 mutex_unlock(&module_mutex);
1962 static void disable_ro_nx(const struct module_layout *layout)
1964 frob_text(layout, set_memory_rw);
1965 frob_rodata(layout, set_memory_rw);
1966 frob_rodata(layout, set_memory_x);
1967 frob_writable_data(layout, set_memory_x);
1971 static void disable_ro_nx(const struct module_layout *layout) { }
1972 static void module_enable_nx(const struct module *mod) { }
1973 static void module_disable_nx(const struct module *mod) { }
1976 void __weak module_memfree(void *module_region)
1978 vfree(module_region);
1981 void __weak module_arch_cleanup(struct module *mod)
1985 void __weak module_arch_freeing_init(struct module *mod)
1989 /* Free a module, remove from lists, etc. */
1990 static void free_module(struct module *mod)
1992 trace_module_free(mod);
1994 mod_sysfs_teardown(mod);
1996 /* We leave it in list to prevent duplicate loads, but make sure
1997 * that noone uses it while it's being deconstructed. */
1998 mutex_lock(&module_mutex);
1999 mod->state = MODULE_STATE_UNFORMED;
2000 mutex_unlock(&module_mutex);
2002 /* Remove dynamic debug info */
2003 ddebug_remove_module(mod->name);
2005 /* Arch-specific cleanup. */
2006 module_arch_cleanup(mod);
2008 /* Module unload stuff */
2009 module_unload_free(mod);
2011 /* Free any allocated parameters. */
2012 destroy_params(mod->kp, mod->num_kp);
2014 /* Now we can delete it from the lists */
2015 mutex_lock(&module_mutex);
2016 /* Unlink carefully: kallsyms could be walking list. */
2017 list_del_rcu(&mod->list);
2018 mod_tree_remove(mod);
2019 /* Remove this module from bug list, this uses list_del_rcu */
2020 module_bug_cleanup(mod);
2021 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2022 synchronize_sched();
2023 mutex_unlock(&module_mutex);
2025 /* This may be empty, but that's OK */
2026 disable_ro_nx(&mod->init_layout);
2027 module_arch_freeing_init(mod);
2028 module_memfree(mod->init_layout.base);
2030 percpu_modfree(mod);
2032 /* Free lock-classes; relies on the preceding sync_rcu(). */
2033 lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
2035 /* Finally, free the core (containing the module structure) */
2036 disable_ro_nx(&mod->core_layout);
2037 module_memfree(mod->core_layout.base);
2040 update_protections(current->mm);
2044 void *__symbol_get(const char *symbol)
2046 struct module *owner;
2047 const struct kernel_symbol *sym;
2050 sym = find_symbol(symbol, &owner, NULL, true, true);
2051 if (sym && strong_try_module_get(owner))
2055 return sym ? (void *)sym->value : NULL;
2057 EXPORT_SYMBOL_GPL(__symbol_get);
2060 * Ensure that an exported symbol [global namespace] does not already exist
2061 * in the kernel or in some other module's exported symbol table.
2063 * You must hold the module_mutex.
2065 static int verify_export_symbols(struct module *mod)
2068 struct module *owner;
2069 const struct kernel_symbol *s;
2071 const struct kernel_symbol *sym;
2074 { mod->syms, mod->num_syms },
2075 { mod->gpl_syms, mod->num_gpl_syms },
2076 { mod->gpl_future_syms, mod->num_gpl_future_syms },
2077 #ifdef CONFIG_UNUSED_SYMBOLS
2078 { mod->unused_syms, mod->num_unused_syms },
2079 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
2083 for (i = 0; i < ARRAY_SIZE(arr); i++) {
2084 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
2085 if (find_symbol(s->name, &owner, NULL, true, false)) {
2086 pr_err("%s: exports duplicate symbol %s"
2088 mod->name, s->name, module_name(owner));
2096 /* Change all symbols so that st_value encodes the pointer directly. */
2097 static int simplify_symbols(struct module *mod, const struct load_info *info)
2099 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2100 Elf_Sym *sym = (void *)symsec->sh_addr;
2101 unsigned long secbase;
2104 const struct kernel_symbol *ksym;
2106 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
2107 const char *name = info->strtab + sym[i].st_name;
2109 switch (sym[i].st_shndx) {
2111 /* Ignore common symbols */
2112 if (!strncmp(name, "__gnu_lto", 9))
2115 /* We compiled with -fno-common. These are not
2116 supposed to happen. */
2117 pr_debug("Common symbol: %s\n", name);
2118 pr_warn("%s: please compile with -fno-common\n",
2124 /* Don't need to do anything */
2125 pr_debug("Absolute symbol: 0x%08lx\n",
2126 (long)sym[i].st_value);
2130 ksym = resolve_symbol_wait(mod, info, name);
2131 /* Ok if resolved. */
2132 if (ksym && !IS_ERR(ksym)) {
2133 sym[i].st_value = ksym->value;
2138 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
2141 pr_warn("%s: Unknown symbol %s (err %li)\n",
2142 mod->name, name, PTR_ERR(ksym));
2143 ret = PTR_ERR(ksym) ?: -ENOENT;
2147 /* Divert to percpu allocation if a percpu var. */
2148 if (sym[i].st_shndx == info->index.pcpu)
2149 secbase = (unsigned long)mod_percpu(mod);
2151 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
2152 sym[i].st_value += secbase;
2160 static int apply_relocations(struct module *mod, const struct load_info *info)
2165 /* Now do relocations. */
2166 for (i = 1; i < info->hdr->e_shnum; i++) {
2167 unsigned int infosec = info->sechdrs[i].sh_info;
2169 /* Not a valid relocation section? */
2170 if (infosec >= info->hdr->e_shnum)
2173 /* Don't bother with non-allocated sections */
2174 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
2177 if (info->sechdrs[i].sh_type == SHT_REL)
2178 err = apply_relocate(info->sechdrs, info->strtab,
2179 info->index.sym, i, mod);
2180 else if (info->sechdrs[i].sh_type == SHT_RELA)
2181 err = apply_relocate_add(info->sechdrs, info->strtab,
2182 info->index.sym, i, mod);
2189 /* Additional bytes needed by arch in front of individual sections */
2190 unsigned int __weak arch_mod_section_prepend(struct module *mod,
2191 unsigned int section)
2193 /* default implementation just returns zero */
2197 /* Update size with this section: return offset. */
2198 static long get_offset(struct module *mod, unsigned int *size,
2199 Elf_Shdr *sechdr, unsigned int section)
2203 *size += arch_mod_section_prepend(mod, section);
2204 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2205 *size = ret + sechdr->sh_size;
2209 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2210 might -- code, read-only data, read-write data, small data. Tally
2211 sizes, and place the offsets into sh_entsize fields: high bit means it
2213 static void layout_sections(struct module *mod, struct load_info *info)
2215 static unsigned long const masks[][2] = {
2216 /* NOTE: all executable code must be the first section
2217 * in this array; otherwise modify the text_size
2218 * finder in the two loops below */
2219 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2220 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
2221 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2222 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2226 for (i = 0; i < info->hdr->e_shnum; i++)
2227 info->sechdrs[i].sh_entsize = ~0UL;
2229 pr_debug("Core section allocation order:\n");
2230 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2231 for (i = 0; i < info->hdr->e_shnum; ++i) {
2232 Elf_Shdr *s = &info->sechdrs[i];
2233 const char *sname = info->secstrings + s->sh_name;
2235 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2236 || (s->sh_flags & masks[m][1])
2237 || s->sh_entsize != ~0UL
2238 || strstarts(sname, ".init"))
2240 s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i);
2241 pr_debug("\t%s\n", sname);
2244 case 0: /* executable */
2245 mod->core_layout.size = debug_align(mod->core_layout.size);
2246 mod->core_layout.text_size = mod->core_layout.size;
2248 case 1: /* RO: text and ro-data */
2249 mod->core_layout.size = debug_align(mod->core_layout.size);
2250 mod->core_layout.ro_size = mod->core_layout.size;
2252 case 3: /* whole core */
2253 mod->core_layout.size = debug_align(mod->core_layout.size);
2258 pr_debug("Init section allocation order:\n");
2259 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2260 for (i = 0; i < info->hdr->e_shnum; ++i) {
2261 Elf_Shdr *s = &info->sechdrs[i];
2262 const char *sname = info->secstrings + s->sh_name;
2264 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2265 || (s->sh_flags & masks[m][1])
2266 || s->sh_entsize != ~0UL
2267 || !strstarts(sname, ".init"))
2269 s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i)
2270 | INIT_OFFSET_MASK);
2271 pr_debug("\t%s\n", sname);
2274 case 0: /* executable */
2275 mod->init_layout.size = debug_align(mod->init_layout.size);
2276 mod->init_layout.text_size = mod->init_layout.size;
2278 case 1: /* RO: text and ro-data */
2279 mod->init_layout.size = debug_align(mod->init_layout.size);
2280 mod->init_layout.ro_size = mod->init_layout.size;
2282 case 3: /* whole init */
2283 mod->init_layout.size = debug_align(mod->init_layout.size);
2289 static void set_license(struct module *mod, const char *license)
2292 license = "unspecified";
2294 if (!license_is_gpl_compatible(license)) {
2295 if (!test_taint(TAINT_PROPRIETARY_MODULE))
2296 pr_warn("%s: module license '%s' taints kernel.\n",
2297 mod->name, license);
2298 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2299 LOCKDEP_NOW_UNRELIABLE);
2303 /* Parse tag=value strings from .modinfo section */
2304 static char *next_string(char *string, unsigned long *secsize)
2306 /* Skip non-zero chars */
2309 if ((*secsize)-- <= 1)
2313 /* Skip any zero padding. */
2314 while (!string[0]) {
2316 if ((*secsize)-- <= 1)
2322 static char *get_modinfo(struct load_info *info, const char *tag)
2325 unsigned int taglen = strlen(tag);
2326 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2327 unsigned long size = infosec->sh_size;
2329 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
2330 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2331 return p + taglen + 1;
2336 static void setup_modinfo(struct module *mod, struct load_info *info)
2338 struct module_attribute *attr;
2341 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2343 attr->setup(mod, get_modinfo(info, attr->attr.name));
2347 static void free_modinfo(struct module *mod)
2349 struct module_attribute *attr;
2352 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2358 #ifdef CONFIG_KALLSYMS
2360 /* lookup symbol in given range of kernel_symbols */
2361 static const struct kernel_symbol *lookup_symbol(const char *name,
2362 const struct kernel_symbol *start,
2363 const struct kernel_symbol *stop)
2365 return bsearch(name, start, stop - start,
2366 sizeof(struct kernel_symbol), cmp_name);
2369 static int is_exported(const char *name, unsigned long value,
2370 const struct module *mod)
2372 const struct kernel_symbol *ks;
2374 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
2376 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
2377 return ks != NULL && ks->value == value;
2381 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
2383 const Elf_Shdr *sechdrs = info->sechdrs;
2385 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2386 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2391 if (sym->st_shndx == SHN_UNDEF)
2393 if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu)
2395 if (sym->st_shndx >= SHN_LORESERVE)
2397 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2399 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2400 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2401 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2403 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2408 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2409 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2414 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2421 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
2422 unsigned int shnum, unsigned int pcpundx)
2424 const Elf_Shdr *sec;
2426 if (src->st_shndx == SHN_UNDEF
2427 || src->st_shndx >= shnum
2431 #ifdef CONFIG_KALLSYMS_ALL
2432 if (src->st_shndx == pcpundx)
2436 sec = sechdrs + src->st_shndx;
2437 if (!(sec->sh_flags & SHF_ALLOC)
2438 #ifndef CONFIG_KALLSYMS_ALL
2439 || !(sec->sh_flags & SHF_EXECINSTR)
2441 || (sec->sh_entsize & INIT_OFFSET_MASK))
2448 * We only allocate and copy the strings needed by the parts of symtab
2449 * we keep. This is simple, but has the effect of making multiple
2450 * copies of duplicates. We could be more sophisticated, see
2451 * linux-kernel thread starting with
2452 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2454 static void layout_symtab(struct module *mod, struct load_info *info)
2456 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2457 Elf_Shdr *strsect = info->sechdrs + info->index.str;
2459 unsigned int i, nsrc, ndst, strtab_size = 0;
2461 /* Put symbol section at end of init part of module. */
2462 symsect->sh_flags |= SHF_ALLOC;
2463 symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect,
2464 info->index.sym) | INIT_OFFSET_MASK;
2465 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
2467 src = (void *)info->hdr + symsect->sh_offset;
2468 nsrc = symsect->sh_size / sizeof(*src);
2470 /* Compute total space required for the core symbols' strtab. */
2471 for (ndst = i = 0; i < nsrc; i++) {
2473 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
2474 info->index.pcpu)) {
2475 strtab_size += strlen(&info->strtab[src[i].st_name])+1;
2480 /* Append room for core symbols at end of core part. */
2481 info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1);
2482 info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym);
2483 mod->core_layout.size += strtab_size;
2484 mod->core_layout.size = debug_align(mod->core_layout.size);
2486 /* Put string table section at end of init part of module. */
2487 strsect->sh_flags |= SHF_ALLOC;
2488 strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect,
2489 info->index.str) | INIT_OFFSET_MASK;
2490 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
2492 /* We'll tack temporary mod_kallsyms on the end. */
2493 mod->init_layout.size = ALIGN(mod->init_layout.size,
2494 __alignof__(struct mod_kallsyms));
2495 info->mod_kallsyms_init_off = mod->init_layout.size;
2496 mod->init_layout.size += sizeof(struct mod_kallsyms);
2497 mod->init_layout.size = debug_align(mod->init_layout.size);
2501 * We use the full symtab and strtab which layout_symtab arranged to
2502 * be appended to the init section. Later we switch to the cut-down
2505 static void add_kallsyms(struct module *mod, const struct load_info *info)
2507 unsigned int i, ndst;
2511 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2513 /* Set up to point into init section. */
2514 mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off;
2516 mod->kallsyms->symtab = (void *)symsec->sh_addr;
2517 mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2518 /* Make sure we get permanent strtab: don't use info->strtab. */
2519 mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2521 /* Set types up while we still have access to sections. */
2522 for (i = 0; i < mod->kallsyms->num_symtab; i++)
2523 mod->kallsyms->symtab[i].st_info
2524 = elf_type(&mod->kallsyms->symtab[i], info);
2526 /* Now populate the cut down core kallsyms for after init. */
2527 mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs;
2528 mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs;
2529 src = mod->kallsyms->symtab;
2530 for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) {
2532 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
2533 info->index.pcpu)) {
2535 dst[ndst++].st_name = s - mod->core_kallsyms.strtab;
2536 s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name],
2540 mod->core_kallsyms.num_symtab = ndst;
2543 static inline void layout_symtab(struct module *mod, struct load_info *info)
2547 static void add_kallsyms(struct module *mod, const struct load_info *info)
2550 #endif /* CONFIG_KALLSYMS */
2552 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2556 #ifdef CONFIG_DYNAMIC_DEBUG
2557 if (ddebug_add_module(debug, num, debug->modname))
2558 pr_err("dynamic debug error adding module: %s\n",
2563 static void dynamic_debug_remove(struct _ddebug *debug)
2566 ddebug_remove_module(debug->modname);
2569 void * __weak module_alloc(unsigned long size)
2571 return vmalloc_exec(size);
2574 #ifdef CONFIG_DEBUG_KMEMLEAK
2575 static void kmemleak_load_module(const struct module *mod,
2576 const struct load_info *info)
2580 /* only scan the sections containing data */
2581 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2583 for (i = 1; i < info->hdr->e_shnum; i++) {
2584 /* Scan all writable sections that's not executable */
2585 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
2586 !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
2587 (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
2590 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2591 info->sechdrs[i].sh_size, GFP_KERNEL);
2595 static inline void kmemleak_load_module(const struct module *mod,
2596 const struct load_info *info)
2601 #ifdef CONFIG_MODULE_SIG
2602 static int module_sig_check(struct load_info *info)
2605 const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2606 const void *mod = info->hdr;
2608 if (info->len > markerlen &&
2609 memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
2610 /* We truncate the module to discard the signature */
2611 info->len -= markerlen;
2612 err = mod_verify_sig(mod, &info->len);
2616 info->sig_ok = true;
2620 /* Not having a signature is only an error if we're strict. */
2621 if (err == -ENOKEY && !sig_enforce)
2626 #else /* !CONFIG_MODULE_SIG */
2627 static int module_sig_check(struct load_info *info)
2631 #endif /* !CONFIG_MODULE_SIG */
2633 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2634 static int elf_header_check(struct load_info *info)
2636 if (info->len < sizeof(*(info->hdr)))
2639 if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2640 || info->hdr->e_type != ET_REL
2641 || !elf_check_arch(info->hdr)
2642 || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2645 if (info->hdr->e_shoff >= info->len
2646 || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2647 info->len - info->hdr->e_shoff))
2653 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2655 static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len)
2658 unsigned long n = min(len, COPY_CHUNK_SIZE);
2660 if (copy_from_user(dst, usrc, n) != 0)
2670 /* Sets info->hdr and info->len. */
2671 static int copy_module_from_user(const void __user *umod, unsigned long len,
2672 struct load_info *info)
2677 if (info->len < sizeof(*(info->hdr)))
2680 err = security_kernel_module_from_file(NULL);
2684 /* Suck in entire file: we'll want most of it. */
2685 info->hdr = __vmalloc(info->len,
2686 GFP_KERNEL | __GFP_HIGHMEM | __GFP_NOWARN, PAGE_KERNEL);
2690 if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
2698 /* Sets info->hdr and info->len. */
2699 static int copy_module_from_fd(int fd, struct load_info *info)
2701 struct fd f = fdget(fd);
2710 err = security_kernel_module_from_file(f.file);
2714 err = vfs_getattr(&f.file->f_path, &stat);
2718 if (stat.size > INT_MAX) {
2723 /* Don't hand 0 to vmalloc, it whines. */
2724 if (stat.size == 0) {
2729 info->hdr = vmalloc(stat.size);
2736 while (pos < stat.size) {
2737 bytes = kernel_read(f.file, pos, (char *)(info->hdr) + pos,
2755 static void free_copy(struct load_info *info)
2760 static int rewrite_section_headers(struct load_info *info, int flags)
2764 /* This should always be true, but let's be sure. */
2765 info->sechdrs[0].sh_addr = 0;
2767 for (i = 1; i < info->hdr->e_shnum; i++) {
2768 Elf_Shdr *shdr = &info->sechdrs[i];
2769 if (shdr->sh_type != SHT_NOBITS
2770 && info->len < shdr->sh_offset + shdr->sh_size) {
2771 pr_err("Module len %lu truncated\n", info->len);
2775 /* Mark all sections sh_addr with their address in the
2777 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2779 #ifndef CONFIG_MODULE_UNLOAD
2780 /* Don't load .exit sections */
2781 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2782 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2786 /* Track but don't keep modinfo and version sections. */
2787 if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
2788 info->index.vers = 0; /* Pretend no __versions section! */
2790 info->index.vers = find_sec(info, "__versions");
2791 info->index.info = find_sec(info, ".modinfo");
2792 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2793 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2798 * Set up our basic convenience variables (pointers to section headers,
2799 * search for module section index etc), and do some basic section
2802 * Return the temporary module pointer (we'll replace it with the final
2803 * one when we move the module sections around).
2805 static struct module *setup_load_info(struct load_info *info, int flags)
2811 /* Set up the convenience variables */
2812 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2813 info->secstrings = (void *)info->hdr
2814 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2816 err = rewrite_section_headers(info, flags);
2818 return ERR_PTR(err);
2820 /* Find internal symbols and strings. */
2821 for (i = 1; i < info->hdr->e_shnum; i++) {
2822 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2823 info->index.sym = i;
2824 info->index.str = info->sechdrs[i].sh_link;
2825 info->strtab = (char *)info->hdr
2826 + info->sechdrs[info->index.str].sh_offset;
2831 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
2832 if (!info->index.mod) {
2833 pr_warn("No module found in object\n");
2834 return ERR_PTR(-ENOEXEC);
2836 /* This is temporary: point mod into copy of data. */
2837 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2839 if (info->index.sym == 0) {
2840 pr_warn("%s: module has no symbols (stripped?)\n", mod->name);
2841 return ERR_PTR(-ENOEXEC);
2844 info->index.pcpu = find_pcpusec(info);
2846 /* Check module struct version now, before we try to use module. */
2847 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2848 return ERR_PTR(-ENOEXEC);
2853 static int check_modinfo(struct module *mod, struct load_info *info, int flags)
2855 const char *modmagic = get_modinfo(info, "vermagic");
2858 if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2861 /* This is allowed: modprobe --force will invalidate it. */
2863 err = try_to_force_load(mod, "bad vermagic");
2866 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2867 pr_err("%s: version magic '%s' should be '%s'\n",
2868 mod->name, modmagic, vermagic);
2872 if (!get_modinfo(info, "intree"))
2873 add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
2875 if (get_modinfo(info, "staging")) {
2876 add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
2877 pr_warn("%s: module is from the staging directory, the quality "
2878 "is unknown, you have been warned.\n", mod->name);
2881 /* Set up license info based on the info section */
2882 set_license(mod, get_modinfo(info, "license"));
2887 static int find_module_sections(struct module *mod, struct load_info *info)
2889 mod->kp = section_objs(info, "__param",
2890 sizeof(*mod->kp), &mod->num_kp);
2891 mod->syms = section_objs(info, "__ksymtab",
2892 sizeof(*mod->syms), &mod->num_syms);
2893 mod->crcs = section_addr(info, "__kcrctab");
2894 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2895 sizeof(*mod->gpl_syms),
2896 &mod->num_gpl_syms);
2897 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2898 mod->gpl_future_syms = section_objs(info,
2899 "__ksymtab_gpl_future",
2900 sizeof(*mod->gpl_future_syms),
2901 &mod->num_gpl_future_syms);
2902 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
2904 #ifdef CONFIG_UNUSED_SYMBOLS
2905 mod->unused_syms = section_objs(info, "__ksymtab_unused",
2906 sizeof(*mod->unused_syms),
2907 &mod->num_unused_syms);
2908 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2909 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
2910 sizeof(*mod->unused_gpl_syms),
2911 &mod->num_unused_gpl_syms);
2912 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
2914 #ifdef CONFIG_CONSTRUCTORS
2915 mod->ctors = section_objs(info, ".ctors",
2916 sizeof(*mod->ctors), &mod->num_ctors);
2918 mod->ctors = section_objs(info, ".init_array",
2919 sizeof(*mod->ctors), &mod->num_ctors);
2920 else if (find_sec(info, ".init_array")) {
2922 * This shouldn't happen with same compiler and binutils
2923 * building all parts of the module.
2925 pr_warn("%s: has both .ctors and .init_array.\n",
2931 #ifdef CONFIG_TRACEPOINTS
2932 mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2933 sizeof(*mod->tracepoints_ptrs),
2934 &mod->num_tracepoints);
2936 #ifdef HAVE_JUMP_LABEL
2937 mod->jump_entries = section_objs(info, "__jump_table",
2938 sizeof(*mod->jump_entries),
2939 &mod->num_jump_entries);
2941 #ifdef CONFIG_EVENT_TRACING
2942 mod->trace_events = section_objs(info, "_ftrace_events",
2943 sizeof(*mod->trace_events),
2944 &mod->num_trace_events);
2945 mod->trace_enums = section_objs(info, "_ftrace_enum_map",
2946 sizeof(*mod->trace_enums),
2947 &mod->num_trace_enums);
2949 #ifdef CONFIG_TRACING
2950 mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2951 sizeof(*mod->trace_bprintk_fmt_start),
2952 &mod->num_trace_bprintk_fmt);
2954 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2955 /* sechdrs[0].sh_size is always zero */
2956 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
2957 sizeof(*mod->ftrace_callsites),
2958 &mod->num_ftrace_callsites);
2961 mod->extable = section_objs(info, "__ex_table",
2962 sizeof(*mod->extable), &mod->num_exentries);
2964 if (section_addr(info, "__obsparm"))
2965 pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
2967 info->debug = section_objs(info, "__verbose",
2968 sizeof(*info->debug), &info->num_debug);
2973 static int move_module(struct module *mod, struct load_info *info)
2978 /* Do the allocs. */
2979 ptr = module_alloc(mod->core_layout.size);
2981 * The pointer to this block is stored in the module structure
2982 * which is inside the block. Just mark it as not being a
2985 kmemleak_not_leak(ptr);
2989 memset(ptr, 0, mod->core_layout.size);
2990 mod->core_layout.base = ptr;
2992 if (mod->init_layout.size) {
2993 ptr = module_alloc(mod->init_layout.size);
2995 * The pointer to this block is stored in the module structure
2996 * which is inside the block. This block doesn't need to be
2997 * scanned as it contains data and code that will be freed
2998 * after the module is initialized.
3000 kmemleak_ignore(ptr);
3002 module_memfree(mod->core_layout.base);
3005 memset(ptr, 0, mod->init_layout.size);
3006 mod->init_layout.base = ptr;
3008 mod->init_layout.base = NULL;
3010 /* Transfer each section which specifies SHF_ALLOC */
3011 pr_debug("final section addresses:\n");
3012 for (i = 0; i < info->hdr->e_shnum; i++) {
3014 Elf_Shdr *shdr = &info->sechdrs[i];
3016 if (!(shdr->sh_flags & SHF_ALLOC))
3019 if (shdr->sh_entsize & INIT_OFFSET_MASK)
3020 dest = mod->init_layout.base
3021 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
3023 dest = mod->core_layout.base + shdr->sh_entsize;
3025 if (shdr->sh_type != SHT_NOBITS)
3026 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
3027 /* Update sh_addr to point to copy in image. */
3028 shdr->sh_addr = (unsigned long)dest;
3029 pr_debug("\t0x%lx %s\n",
3030 (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
3036 static int check_module_license_and_versions(struct module *mod)
3039 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3040 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3041 * using GPL-only symbols it needs.
3043 if (strcmp(mod->name, "ndiswrapper") == 0)
3044 add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
3046 /* driverloader was caught wrongly pretending to be under GPL */
3047 if (strcmp(mod->name, "driverloader") == 0)
3048 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
3049 LOCKDEP_NOW_UNRELIABLE);
3051 /* lve claims to be GPL but upstream won't provide source */
3052 if (strcmp(mod->name, "lve") == 0)
3053 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
3054 LOCKDEP_NOW_UNRELIABLE);
3056 #ifdef CONFIG_MODVERSIONS
3057 if ((mod->num_syms && !mod->crcs)
3058 || (mod->num_gpl_syms && !mod->gpl_crcs)
3059 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
3060 #ifdef CONFIG_UNUSED_SYMBOLS
3061 || (mod->num_unused_syms && !mod->unused_crcs)
3062 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
3065 return try_to_force_load(mod,
3066 "no versions for exported symbols");
3072 static void flush_module_icache(const struct module *mod)
3074 mm_segment_t old_fs;
3076 /* flush the icache in correct context */
3081 * Flush the instruction cache, since we've played with text.
3082 * Do it before processing of module parameters, so the module
3083 * can provide parameter accessor functions of its own.
3085 if (mod->init_layout.base)
3086 flush_icache_range((unsigned long)mod->init_layout.base,
3087 (unsigned long)mod->init_layout.base
3088 + mod->init_layout.size);
3089 flush_icache_range((unsigned long)mod->core_layout.base,
3090 (unsigned long)mod->core_layout.base + mod->core_layout.size);
3095 int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
3103 static struct module *layout_and_allocate(struct load_info *info, int flags)
3105 /* Module within temporary copy. */
3109 mod = setup_load_info(info, flags);
3113 err = check_modinfo(mod, info, flags);
3115 return ERR_PTR(err);
3117 /* Allow arches to frob section contents and sizes. */
3118 err = module_frob_arch_sections(info->hdr, info->sechdrs,
3119 info->secstrings, mod);
3121 return ERR_PTR(err);
3123 /* We will do a special allocation for per-cpu sections later. */
3124 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
3126 /* Determine total sizes, and put offsets in sh_entsize. For now
3127 this is done generically; there doesn't appear to be any
3128 special cases for the architectures. */
3129 layout_sections(mod, info);
3130 layout_symtab(mod, info);
3132 /* Allocate and move to the final place */
3133 err = move_module(mod, info);
3135 return ERR_PTR(err);
3137 /* Module has been copied to its final place now: return it. */
3138 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
3139 kmemleak_load_module(mod, info);
3143 /* mod is no longer valid after this! */
3144 static void module_deallocate(struct module *mod, struct load_info *info)
3146 percpu_modfree(mod);
3147 module_arch_freeing_init(mod);
3148 module_memfree(mod->init_layout.base);
3149 module_memfree(mod->core_layout.base);
3152 int __weak module_finalize(const Elf_Ehdr *hdr,
3153 const Elf_Shdr *sechdrs,
3159 static int post_relocation(struct module *mod, const struct load_info *info)
3161 /* Sort exception table now relocations are done. */
3162 sort_extable(mod->extable, mod->extable + mod->num_exentries);
3164 /* Copy relocated percpu area over. */
3165 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
3166 info->sechdrs[info->index.pcpu].sh_size);
3168 /* Setup kallsyms-specific fields. */
3169 add_kallsyms(mod, info);
3171 /* Arch-specific module finalizing. */
3172 return module_finalize(info->hdr, info->sechdrs, mod);
3175 /* Is this module of this name done loading? No locks held. */
3176 static bool finished_loading(const char *name)
3182 * The module_mutex should not be a heavily contended lock;
3183 * if we get the occasional sleep here, we'll go an extra iteration
3184 * in the wait_event_interruptible(), which is harmless.
3186 sched_annotate_sleep();
3187 mutex_lock(&module_mutex);
3188 mod = find_module_all(name, strlen(name), true);
3189 ret = !mod || mod->state == MODULE_STATE_LIVE
3190 || mod->state == MODULE_STATE_GOING;
3191 mutex_unlock(&module_mutex);
3196 /* Call module constructors. */
3197 static void do_mod_ctors(struct module *mod)
3199 #ifdef CONFIG_CONSTRUCTORS
3202 for (i = 0; i < mod->num_ctors; i++)
3207 /* For freeing module_init on success, in case kallsyms traversing */
3208 struct mod_initfree {
3209 struct rcu_head rcu;
3213 static void do_free_init(struct rcu_head *head)
3215 struct mod_initfree *m = container_of(head, struct mod_initfree, rcu);
3216 module_memfree(m->module_init);
3221 * This is where the real work happens.
3223 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3224 * helper command 'lx-symbols'.
3226 static noinline int do_init_module(struct module *mod)
3229 struct mod_initfree *freeinit;
3231 freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
3236 freeinit->module_init = mod->init_layout.base;
3239 * We want to find out whether @mod uses async during init. Clear
3240 * PF_USED_ASYNC. async_schedule*() will set it.
3242 current->flags &= ~PF_USED_ASYNC;
3245 /* Start the module */
3246 if (mod->init != NULL)
3247 ret = do_one_initcall(mod->init);
3249 goto fail_free_freeinit;
3252 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3253 "follow 0/-E convention\n"
3254 "%s: loading module anyway...\n",
3255 __func__, mod->name, ret, __func__);
3259 /* Now it's a first class citizen! */
3260 mod->state = MODULE_STATE_LIVE;
3261 blocking_notifier_call_chain(&module_notify_list,
3262 MODULE_STATE_LIVE, mod);
3265 * We need to finish all async code before the module init sequence
3266 * is done. This has potential to deadlock. For example, a newly
3267 * detected block device can trigger request_module() of the
3268 * default iosched from async probing task. Once userland helper
3269 * reaches here, async_synchronize_full() will wait on the async
3270 * task waiting on request_module() and deadlock.
3272 * This deadlock is avoided by perfomring async_synchronize_full()
3273 * iff module init queued any async jobs. This isn't a full
3274 * solution as it will deadlock the same if module loading from
3275 * async jobs nests more than once; however, due to the various
3276 * constraints, this hack seems to be the best option for now.
3277 * Please refer to the following thread for details.
3279 * http://thread.gmane.org/gmane.linux.kernel/1420814
3281 if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC))
3282 async_synchronize_full();
3284 mutex_lock(&module_mutex);
3285 /* Drop initial reference. */
3287 trim_init_extable(mod);
3288 #ifdef CONFIG_KALLSYMS
3289 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3290 rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
3292 mod_tree_remove_init(mod);
3293 disable_ro_nx(&mod->init_layout);
3294 module_arch_freeing_init(mod);
3295 mod->init_layout.base = NULL;
3296 mod->init_layout.size = 0;
3297 mod->init_layout.ro_size = 0;
3298 mod->init_layout.text_size = 0;
3300 * We want to free module_init, but be aware that kallsyms may be
3301 * walking this with preempt disabled. In all the failure paths, we
3302 * call synchronize_sched(), but we don't want to slow down the success
3303 * path, so use actual RCU here.
3305 call_rcu_sched(&freeinit->rcu, do_free_init);
3306 mutex_unlock(&module_mutex);
3307 wake_up_all(&module_wq);
3314 /* Try to protect us from buggy refcounters. */
3315 mod->state = MODULE_STATE_GOING;
3316 synchronize_sched();
3318 blocking_notifier_call_chain(&module_notify_list,
3319 MODULE_STATE_GOING, mod);
3320 klp_module_going(mod);
3321 ftrace_release_mod(mod);
3323 wake_up_all(&module_wq);
3327 static int may_init_module(void)
3329 if (!capable(CAP_SYS_MODULE) || modules_disabled)
3336 * We try to place it in the list now to make sure it's unique before
3337 * we dedicate too many resources. In particular, temporary percpu
3338 * memory exhaustion.
3340 static int add_unformed_module(struct module *mod)
3345 mod->state = MODULE_STATE_UNFORMED;
3348 mutex_lock(&module_mutex);
3349 old = find_module_all(mod->name, strlen(mod->name), true);
3351 if (old->state == MODULE_STATE_COMING
3352 || old->state == MODULE_STATE_UNFORMED) {
3353 /* Wait in case it fails to load. */
3354 mutex_unlock(&module_mutex);
3355 err = wait_event_interruptible(module_wq,
3356 finished_loading(mod->name));
3364 mod_update_bounds(mod);
3365 list_add_rcu(&mod->list, &modules);
3366 mod_tree_insert(mod);
3370 mutex_unlock(&module_mutex);
3375 static int complete_formation(struct module *mod, struct load_info *info)
3379 mutex_lock(&module_mutex);
3381 /* Find duplicate symbols (must be called under lock). */
3382 err = verify_export_symbols(mod);
3386 /* This relies on module_mutex for list integrity. */
3387 module_bug_finalize(info->hdr, info->sechdrs, mod);
3389 /* Set RO and NX regions */
3390 module_enable_ro(mod);
3391 module_enable_nx(mod);
3393 /* Mark state as coming so strong_try_module_get() ignores us,
3394 * but kallsyms etc. can see us. */
3395 mod->state = MODULE_STATE_COMING;
3396 mutex_unlock(&module_mutex);
3401 mutex_unlock(&module_mutex);
3405 static int prepare_coming_module(struct module *mod)
3409 ftrace_module_enable(mod);
3410 err = klp_module_coming(mod);
3414 blocking_notifier_call_chain(&module_notify_list,
3415 MODULE_STATE_COMING, mod);
3419 static int unknown_module_param_cb(char *param, char *val, const char *modname,
3422 struct module *mod = arg;
3425 if (strcmp(param, "async_probe") == 0) {
3426 mod->async_probe_requested = true;
3430 /* Check for magic 'dyndbg' arg */
3431 ret = ddebug_dyndbg_module_param_cb(param, val, modname);
3433 pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
3437 /* Allocate and load the module: note that size of section 0 is always
3438 zero, and we rely on this for optional sections. */
3439 static int load_module(struct load_info *info, const char __user *uargs,
3446 err = module_sig_check(info);
3450 err = elf_header_check(info);
3454 /* Figure out module layout, and allocate all the memory. */
3455 mod = layout_and_allocate(info, flags);
3461 /* Reserve our place in the list. */
3462 err = add_unformed_module(mod);
3466 #ifdef CONFIG_MODULE_SIG
3467 mod->sig_ok = info->sig_ok;
3469 pr_notice_once("%s: module verification failed: signature "
3470 "and/or required key missing - tainting "
3471 "kernel\n", mod->name);
3472 add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
3476 /* To avoid stressing percpu allocator, do this once we're unique. */
3477 err = percpu_modalloc(mod, info);
3481 /* Now module is in final location, initialize linked lists, etc. */
3482 err = module_unload_init(mod);
3486 init_param_lock(mod);
3488 /* Now we've got everything in the final locations, we can
3489 * find optional sections. */
3490 err = find_module_sections(mod, info);
3494 err = check_module_license_and_versions(mod);
3498 /* Set up MODINFO_ATTR fields */
3499 setup_modinfo(mod, info);
3501 /* Fix up syms, so that st_value is a pointer to location. */
3502 err = simplify_symbols(mod, info);
3506 err = apply_relocations(mod, info);
3510 err = post_relocation(mod, info);
3514 flush_module_icache(mod);
3516 /* Now copy in args */
3517 mod->args = strndup_user(uargs, ~0UL >> 1);
3518 if (IS_ERR(mod->args)) {
3519 err = PTR_ERR(mod->args);
3520 goto free_arch_cleanup;
3523 dynamic_debug_setup(info->debug, info->num_debug);
3525 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3526 ftrace_module_init(mod);
3528 /* Finally it's fully formed, ready to start executing. */
3529 err = complete_formation(mod, info);
3531 goto ddebug_cleanup;
3533 err = prepare_coming_module(mod);
3537 /* Module is ready to execute: parsing args may do that. */
3538 after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
3540 unknown_module_param_cb);
3541 if (IS_ERR(after_dashes)) {
3542 err = PTR_ERR(after_dashes);
3543 goto coming_cleanup;
3544 } else if (after_dashes) {
3545 pr_warn("%s: parameters '%s' after `--' ignored\n",
3546 mod->name, after_dashes);
3549 /* Link in to syfs. */
3550 err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3552 goto coming_cleanup;
3554 /* Get rid of temporary copy. */
3558 trace_module_load(mod);
3560 return do_init_module(mod);
3563 blocking_notifier_call_chain(&module_notify_list,
3564 MODULE_STATE_GOING, mod);
3565 klp_module_going(mod);
3568 /* module_bug_cleanup needs module_mutex protection */
3569 mutex_lock(&module_mutex);
3570 module_bug_cleanup(mod);
3571 mutex_unlock(&module_mutex);
3573 /* we can't deallocate the module until we clear memory protection */
3574 module_disable_ro(mod);
3575 module_disable_nx(mod);
3578 dynamic_debug_remove(info->debug);
3579 synchronize_sched();
3582 module_arch_cleanup(mod);
3586 module_unload_free(mod);
3588 mutex_lock(&module_mutex);
3589 /* Unlink carefully: kallsyms could be walking list. */
3590 list_del_rcu(&mod->list);
3591 mod_tree_remove(mod);
3592 wake_up_all(&module_wq);
3593 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3594 synchronize_sched();
3595 mutex_unlock(&module_mutex);
3598 * Ftrace needs to clean up what it initialized.
3599 * This does nothing if ftrace_module_init() wasn't called,
3600 * but it must be called outside of module_mutex.
3602 ftrace_release_mod(mod);
3603 /* Free lock-classes; relies on the preceding sync_rcu() */
3604 lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
3606 module_deallocate(mod, info);
3612 SYSCALL_DEFINE3(init_module, void __user *, umod,
3613 unsigned long, len, const char __user *, uargs)
3616 struct load_info info = { };
3618 err = may_init_module();
3622 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3625 err = copy_module_from_user(umod, len, &info);
3629 return load_module(&info, uargs, 0);
3632 SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3635 struct load_info info = { };
3637 err = may_init_module();
3641 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3643 if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3644 |MODULE_INIT_IGNORE_VERMAGIC))
3647 err = copy_module_from_fd(fd, &info);
3651 return load_module(&info, uargs, flags);
3654 static inline int within(unsigned long addr, void *start, unsigned long size)
3656 return ((void *)addr >= start && (void *)addr < start + size);
3659 #ifdef CONFIG_KALLSYMS
3661 * This ignores the intensely annoying "mapping symbols" found
3662 * in ARM ELF files: $a, $t and $d.
3664 static inline int is_arm_mapping_symbol(const char *str)
3666 if (str[0] == '.' && str[1] == 'L')
3668 return str[0] == '$' && strchr("axtd", str[1])
3669 && (str[2] == '\0' || str[2] == '.');
3672 static const char *symname(struct mod_kallsyms *kallsyms, unsigned int symnum)
3674 return kallsyms->strtab + kallsyms->symtab[symnum].st_name;
3677 static const char *get_ksymbol(struct module *mod,
3679 unsigned long *size,
3680 unsigned long *offset)
3682 unsigned int i, best = 0;
3683 unsigned long nextval;
3684 struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
3686 /* At worse, next value is at end of module */
3687 if (within_module_init(addr, mod))
3688 nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size;
3690 nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size;
3692 /* Scan for closest preceding symbol, and next symbol. (ELF
3693 starts real symbols at 1). */
3694 for (i = 1; i < kallsyms->num_symtab; i++) {
3695 if (kallsyms->symtab[i].st_shndx == SHN_UNDEF)
3698 /* We ignore unnamed symbols: they're uninformative
3699 * and inserted at a whim. */
3700 if (*symname(kallsyms, i) == '\0'
3701 || is_arm_mapping_symbol(symname(kallsyms, i)))
3704 if (kallsyms->symtab[i].st_value <= addr
3705 && kallsyms->symtab[i].st_value > kallsyms->symtab[best].st_value)
3707 if (kallsyms->symtab[i].st_value > addr
3708 && kallsyms->symtab[i].st_value < nextval)
3709 nextval = kallsyms->symtab[i].st_value;
3716 *size = nextval - kallsyms->symtab[best].st_value;
3718 *offset = addr - kallsyms->symtab[best].st_value;
3719 return symname(kallsyms, best);
3722 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3723 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3724 const char *module_address_lookup(unsigned long addr,
3725 unsigned long *size,
3726 unsigned long *offset,
3730 const char *ret = NULL;
3734 mod = __module_address(addr);
3737 *modname = mod->name;
3738 ret = get_ksymbol(mod, addr, size, offset);
3740 /* Make a copy in here where it's safe */
3742 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
3750 int lookup_module_symbol_name(unsigned long addr, char *symname)
3755 list_for_each_entry_rcu(mod, &modules, list) {
3756 if (mod->state == MODULE_STATE_UNFORMED)
3758 if (within_module(addr, mod)) {
3761 sym = get_ksymbol(mod, addr, NULL, NULL);
3764 strlcpy(symname, sym, KSYM_NAME_LEN);
3774 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
3775 unsigned long *offset, char *modname, char *name)
3780 list_for_each_entry_rcu(mod, &modules, list) {
3781 if (mod->state == MODULE_STATE_UNFORMED)
3783 if (within_module(addr, mod)) {
3786 sym = get_ksymbol(mod, addr, size, offset);
3790 strlcpy(modname, mod->name, MODULE_NAME_LEN);
3792 strlcpy(name, sym, KSYM_NAME_LEN);
3802 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
3803 char *name, char *module_name, int *exported)
3808 list_for_each_entry_rcu(mod, &modules, list) {
3809 struct mod_kallsyms *kallsyms;
3811 if (mod->state == MODULE_STATE_UNFORMED)
3813 kallsyms = rcu_dereference_sched(mod->kallsyms);
3814 if (symnum < kallsyms->num_symtab) {
3815 *value = kallsyms->symtab[symnum].st_value;
3816 *type = kallsyms->symtab[symnum].st_info;
3817 strlcpy(name, symname(kallsyms, symnum), KSYM_NAME_LEN);
3818 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
3819 *exported = is_exported(name, *value, mod);
3823 symnum -= kallsyms->num_symtab;
3829 static unsigned long mod_find_symname(struct module *mod, const char *name)
3832 struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
3834 for (i = 0; i < kallsyms->num_symtab; i++)
3835 if (strcmp(name, symname(kallsyms, i)) == 0 &&
3836 kallsyms->symtab[i].st_info != 'U')
3837 return kallsyms->symtab[i].st_value;
3841 /* Look for this name: can be of form module:name. */
3842 unsigned long module_kallsyms_lookup_name(const char *name)
3846 unsigned long ret = 0;
3848 /* Don't lock: we're in enough trouble already. */
3850 if ((colon = strchr(name, ':')) != NULL) {
3851 if ((mod = find_module_all(name, colon - name, false)) != NULL)
3852 ret = mod_find_symname(mod, colon+1);
3854 list_for_each_entry_rcu(mod, &modules, list) {
3855 if (mod->state == MODULE_STATE_UNFORMED)
3857 if ((ret = mod_find_symname(mod, name)) != 0)
3865 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3866 struct module *, unsigned long),
3873 module_assert_mutex();
3875 list_for_each_entry(mod, &modules, list) {
3876 /* We hold module_mutex: no need for rcu_dereference_sched */
3877 struct mod_kallsyms *kallsyms = mod->kallsyms;
3879 if (mod->state == MODULE_STATE_UNFORMED)
3881 for (i = 0; i < kallsyms->num_symtab; i++) {
3882 ret = fn(data, symname(kallsyms, i),
3883 mod, kallsyms->symtab[i].st_value);
3890 #endif /* CONFIG_KALLSYMS */
3892 static char *module_flags(struct module *mod, char *buf)
3896 BUG_ON(mod->state == MODULE_STATE_UNFORMED);
3898 mod->state == MODULE_STATE_GOING ||
3899 mod->state == MODULE_STATE_COMING) {
3901 bx += module_flags_taint(mod, buf + bx);
3902 /* Show a - for module-is-being-unloaded */
3903 if (mod->state == MODULE_STATE_GOING)
3905 /* Show a + for module-is-being-loaded */
3906 if (mod->state == MODULE_STATE_COMING)
3915 #ifdef CONFIG_PROC_FS
3916 /* Called by the /proc file system to return a list of modules. */
3917 static void *m_start(struct seq_file *m, loff_t *pos)
3919 mutex_lock(&module_mutex);
3920 return seq_list_start(&modules, *pos);
3923 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3925 return seq_list_next(p, &modules, pos);
3928 static void m_stop(struct seq_file *m, void *p)
3930 mutex_unlock(&module_mutex);
3933 static int m_show(struct seq_file *m, void *p)
3935 struct module *mod = list_entry(p, struct module, list);
3938 /* We always ignore unformed modules. */
3939 if (mod->state == MODULE_STATE_UNFORMED)
3942 seq_printf(m, "%s %u",
3943 mod->name, mod->init_layout.size + mod->core_layout.size);
3944 print_unload_info(m, mod);
3946 /* Informative for users. */
3947 seq_printf(m, " %s",
3948 mod->state == MODULE_STATE_GOING ? "Unloading" :
3949 mod->state == MODULE_STATE_COMING ? "Loading" :
3951 /* Used by oprofile and other similar tools. */
3952 seq_printf(m, " 0x%pK", mod->core_layout.base);
3956 seq_printf(m, " %s", module_flags(mod, buf));
3962 /* Format: modulename size refcount deps address
3964 Where refcount is a number or -, and deps is a comma-separated list
3967 static const struct seq_operations modules_op = {
3974 static int modules_open(struct inode *inode, struct file *file)
3976 return seq_open(file, &modules_op);
3979 static const struct file_operations proc_modules_operations = {
3980 .open = modules_open,
3982 .llseek = seq_lseek,
3983 .release = seq_release,
3986 static int __init proc_modules_init(void)
3988 proc_create("modules", 0, NULL, &proc_modules_operations);
3991 module_init(proc_modules_init);
3994 /* Given an address, look for it in the module exception tables. */
3995 const struct exception_table_entry *search_module_extables(unsigned long addr)
3997 const struct exception_table_entry *e = NULL;
4001 list_for_each_entry_rcu(mod, &modules, list) {
4002 if (mod->state == MODULE_STATE_UNFORMED)
4004 if (mod->num_exentries == 0)
4007 e = search_extable(mod->extable,
4008 mod->extable + mod->num_exentries - 1,
4015 /* Now, if we found one, we are running inside it now, hence
4016 we cannot unload the module, hence no refcnt needed. */
4021 * is_module_address - is this address inside a module?
4022 * @addr: the address to check.
4024 * See is_module_text_address() if you simply want to see if the address
4025 * is code (not data).
4027 bool is_module_address(unsigned long addr)
4032 ret = __module_address(addr) != NULL;
4039 * __module_address - get the module which contains an address.
4040 * @addr: the address.
4042 * Must be called with preempt disabled or module mutex held so that
4043 * module doesn't get freed during this.
4045 struct module *__module_address(unsigned long addr)
4049 if (addr < module_addr_min || addr > module_addr_max)
4052 module_assert_mutex_or_preempt();
4054 mod = mod_find(addr);
4056 BUG_ON(!within_module(addr, mod));
4057 if (mod->state == MODULE_STATE_UNFORMED)
4062 EXPORT_SYMBOL_GPL(__module_address);
4065 * is_module_text_address - is this address inside module code?
4066 * @addr: the address to check.
4068 * See is_module_address() if you simply want to see if the address is
4069 * anywhere in a module. See kernel_text_address() for testing if an
4070 * address corresponds to kernel or module code.
4072 bool is_module_text_address(unsigned long addr)
4077 ret = __module_text_address(addr) != NULL;
4084 * __module_text_address - get the module whose code contains an address.
4085 * @addr: the address.
4087 * Must be called with preempt disabled or module mutex held so that
4088 * module doesn't get freed during this.
4090 struct module *__module_text_address(unsigned long addr)
4092 struct module *mod = __module_address(addr);
4094 /* Make sure it's within the text section. */
4095 if (!within(addr, mod->init_layout.base, mod->init_layout.text_size)
4096 && !within(addr, mod->core_layout.base, mod->core_layout.text_size))
4101 EXPORT_SYMBOL_GPL(__module_text_address);
4103 /* Don't grab lock, we're oopsing. */
4104 void print_modules(void)
4109 printk(KERN_DEFAULT "Modules linked in:");
4110 /* Most callers should already have preempt disabled, but make sure */
4112 list_for_each_entry_rcu(mod, &modules, list) {
4113 if (mod->state == MODULE_STATE_UNFORMED)
4115 pr_cont(" %s%s", mod->name, module_flags(mod, buf));
4118 if (last_unloaded_module[0])
4119 pr_cont(" [last unloaded: %s]", last_unloaded_module);
4123 #ifdef CONFIG_MODVERSIONS
4124 /* Generate the signature for all relevant module structures here.
4125 * If these change, we don't want to try to parse the module. */
4126 void module_layout(struct module *mod,
4127 struct modversion_info *ver,
4128 struct kernel_param *kp,
4129 struct kernel_symbol *ks,
4130 struct tracepoint * const *tp)
4133 EXPORT_SYMBOL(module_layout);