1 // SPDX-License-Identifier: GPL-2.0-or-later
3 Copyright (C) 2002 Richard Henderson
4 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
7 #include <linux/export.h>
8 #include <linux/extable.h>
9 #include <linux/moduleloader.h>
10 #include <linux/module_signature.h>
11 #include <linux/trace_events.h>
12 #include <linux/init.h>
13 #include <linux/kallsyms.h>
14 #include <linux/file.h>
16 #include <linux/sysfs.h>
17 #include <linux/kernel.h>
18 #include <linux/slab.h>
19 #include <linux/vmalloc.h>
20 #include <linux/elf.h>
21 #include <linux/proc_fs.h>
22 #include <linux/security.h>
23 #include <linux/seq_file.h>
24 #include <linux/syscalls.h>
25 #include <linux/fcntl.h>
26 #include <linux/rcupdate.h>
27 #include <linux/capability.h>
28 #include <linux/cpu.h>
29 #include <linux/moduleparam.h>
30 #include <linux/errno.h>
31 #include <linux/err.h>
32 #include <linux/vermagic.h>
33 #include <linux/notifier.h>
34 #include <linux/sched.h>
35 #include <linux/device.h>
36 #include <linux/string.h>
37 #include <linux/mutex.h>
38 #include <linux/rculist.h>
39 #include <linux/uaccess.h>
40 #include <asm/cacheflush.h>
41 #include <linux/set_memory.h>
42 #include <asm/mmu_context.h>
43 #include <linux/license.h>
44 #include <asm/sections.h>
45 #include <linux/tracepoint.h>
46 #include <linux/ftrace.h>
47 #include <linux/livepatch.h>
48 #include <linux/async.h>
49 #include <linux/percpu.h>
50 #include <linux/kmemleak.h>
51 #include <linux/jump_label.h>
52 #include <linux/pfn.h>
53 #include <linux/bsearch.h>
54 #include <linux/dynamic_debug.h>
55 #include <linux/audit.h>
56 #include <uapi/linux/module.h>
57 #include "module-internal.h"
59 #define CREATE_TRACE_POINTS
60 #include <trace/events/module.h>
62 #ifndef ARCH_SHF_SMALL
63 #define ARCH_SHF_SMALL 0
67 * Modules' sections will be aligned on page boundaries
68 * to ensure complete separation of code and data, but
69 * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y
71 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
72 # define debug_align(X) ALIGN(X, PAGE_SIZE)
74 # define debug_align(X) (X)
77 /* If this is set, the section belongs in the init part of the module */
78 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
82 * 1) List of modules (also safely readable with preempt_disable),
83 * 2) module_use links,
84 * 3) module_addr_min/module_addr_max.
85 * (delete and add uses RCU list operations). */
86 DEFINE_MUTEX(module_mutex);
87 EXPORT_SYMBOL_GPL(module_mutex);
88 static LIST_HEAD(modules);
90 /* Work queue for freeing init sections in success case */
91 static struct work_struct init_free_wq;
92 static struct llist_head init_free_list;
94 #ifdef CONFIG_MODULES_TREE_LOOKUP
97 * Use a latched RB-tree for __module_address(); this allows us to use
98 * RCU-sched lookups of the address from any context.
100 * This is conditional on PERF_EVENTS || TRACING because those can really hit
101 * __module_address() hard by doing a lot of stack unwinding; potentially from
105 static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
107 struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
109 return (unsigned long)layout->base;
112 static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
114 struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
116 return (unsigned long)layout->size;
119 static __always_inline bool
120 mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b)
122 return __mod_tree_val(a) < __mod_tree_val(b);
125 static __always_inline int
126 mod_tree_comp(void *key, struct latch_tree_node *n)
128 unsigned long val = (unsigned long)key;
129 unsigned long start, end;
131 start = __mod_tree_val(n);
135 end = start + __mod_tree_size(n);
142 static const struct latch_tree_ops mod_tree_ops = {
143 .less = mod_tree_less,
144 .comp = mod_tree_comp,
147 static struct mod_tree_root {
148 struct latch_tree_root root;
149 unsigned long addr_min;
150 unsigned long addr_max;
151 } mod_tree __cacheline_aligned = {
155 #define module_addr_min mod_tree.addr_min
156 #define module_addr_max mod_tree.addr_max
158 static noinline void __mod_tree_insert(struct mod_tree_node *node)
160 latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops);
163 static void __mod_tree_remove(struct mod_tree_node *node)
165 latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops);
169 * These modifications: insert, remove_init and remove; are serialized by the
172 static void mod_tree_insert(struct module *mod)
174 mod->core_layout.mtn.mod = mod;
175 mod->init_layout.mtn.mod = mod;
177 __mod_tree_insert(&mod->core_layout.mtn);
178 if (mod->init_layout.size)
179 __mod_tree_insert(&mod->init_layout.mtn);
182 static void mod_tree_remove_init(struct module *mod)
184 if (mod->init_layout.size)
185 __mod_tree_remove(&mod->init_layout.mtn);
188 static void mod_tree_remove(struct module *mod)
190 __mod_tree_remove(&mod->core_layout.mtn);
191 mod_tree_remove_init(mod);
194 static struct module *mod_find(unsigned long addr)
196 struct latch_tree_node *ltn;
198 ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops);
202 return container_of(ltn, struct mod_tree_node, node)->mod;
205 #else /* MODULES_TREE_LOOKUP */
207 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
209 static void mod_tree_insert(struct module *mod) { }
210 static void mod_tree_remove_init(struct module *mod) { }
211 static void mod_tree_remove(struct module *mod) { }
213 static struct module *mod_find(unsigned long addr)
217 list_for_each_entry_rcu(mod, &modules, list,
218 lockdep_is_held(&module_mutex)) {
219 if (within_module(addr, mod))
226 #endif /* MODULES_TREE_LOOKUP */
229 * Bounds of module text, for speeding up __module_address.
230 * Protected by module_mutex.
232 static void __mod_update_bounds(void *base, unsigned int size)
234 unsigned long min = (unsigned long)base;
235 unsigned long max = min + size;
237 if (min < module_addr_min)
238 module_addr_min = min;
239 if (max > module_addr_max)
240 module_addr_max = max;
243 static void mod_update_bounds(struct module *mod)
245 __mod_update_bounds(mod->core_layout.base, mod->core_layout.size);
246 if (mod->init_layout.size)
247 __mod_update_bounds(mod->init_layout.base, mod->init_layout.size);
250 #ifdef CONFIG_KGDB_KDB
251 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
252 #endif /* CONFIG_KGDB_KDB */
254 static void module_assert_mutex(void)
256 lockdep_assert_held(&module_mutex);
259 static void module_assert_mutex_or_preempt(void)
261 #ifdef CONFIG_LOCKDEP
262 if (unlikely(!debug_locks))
265 WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
266 !lockdep_is_held(&module_mutex));
270 static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE);
271 module_param(sig_enforce, bool_enable_only, 0644);
274 * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
275 * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
277 bool is_module_sig_enforced(void)
281 EXPORT_SYMBOL(is_module_sig_enforced);
283 void set_module_sig_enforced(void)
288 /* Block module loading/unloading? */
289 int modules_disabled = 0;
290 core_param(nomodule, modules_disabled, bint, 0);
292 /* Waiting for a module to finish initializing? */
293 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
295 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
297 int register_module_notifier(struct notifier_block *nb)
299 return blocking_notifier_chain_register(&module_notify_list, nb);
301 EXPORT_SYMBOL(register_module_notifier);
303 int unregister_module_notifier(struct notifier_block *nb)
305 return blocking_notifier_chain_unregister(&module_notify_list, nb);
307 EXPORT_SYMBOL(unregister_module_notifier);
310 * We require a truly strong try_module_get(): 0 means success.
311 * Otherwise an error is returned due to ongoing or failed
312 * initialization etc.
314 static inline int strong_try_module_get(struct module *mod)
316 BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
317 if (mod && mod->state == MODULE_STATE_COMING)
319 if (try_module_get(mod))
325 static inline void add_taint_module(struct module *mod, unsigned flag,
326 enum lockdep_ok lockdep_ok)
328 add_taint(flag, lockdep_ok);
329 set_bit(flag, &mod->taints);
333 * A thread that wants to hold a reference to a module only while it
334 * is running can call this to safely exit. nfsd and lockd use this.
336 void __noreturn __module_put_and_exit(struct module *mod, long code)
341 EXPORT_SYMBOL(__module_put_and_exit);
343 /* Find a module section: 0 means not found. */
344 static unsigned int find_sec(const struct load_info *info, const char *name)
348 for (i = 1; i < info->hdr->e_shnum; i++) {
349 Elf_Shdr *shdr = &info->sechdrs[i];
350 /* Alloc bit cleared means "ignore it." */
351 if ((shdr->sh_flags & SHF_ALLOC)
352 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
358 /* Find a module section, or NULL. */
359 static void *section_addr(const struct load_info *info, const char *name)
361 /* Section 0 has sh_addr 0. */
362 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
365 /* Find a module section, or NULL. Fill in number of "objects" in section. */
366 static void *section_objs(const struct load_info *info,
371 unsigned int sec = find_sec(info, name);
373 /* Section 0 has sh_addr 0 and sh_size 0. */
374 *num = info->sechdrs[sec].sh_size / object_size;
375 return (void *)info->sechdrs[sec].sh_addr;
378 /* Provided by the linker */
379 extern const struct kernel_symbol __start___ksymtab[];
380 extern const struct kernel_symbol __stop___ksymtab[];
381 extern const struct kernel_symbol __start___ksymtab_gpl[];
382 extern const struct kernel_symbol __stop___ksymtab_gpl[];
383 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
384 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
385 extern const s32 __start___kcrctab[];
386 extern const s32 __start___kcrctab_gpl[];
387 extern const s32 __start___kcrctab_gpl_future[];
388 #ifdef CONFIG_UNUSED_SYMBOLS
389 extern const struct kernel_symbol __start___ksymtab_unused[];
390 extern const struct kernel_symbol __stop___ksymtab_unused[];
391 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
392 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
393 extern const s32 __start___kcrctab_unused[];
394 extern const s32 __start___kcrctab_unused_gpl[];
397 #ifndef CONFIG_MODVERSIONS
398 #define symversion(base, idx) NULL
400 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
403 static bool each_symbol_in_section(const struct symsearch *arr,
404 unsigned int arrsize,
405 struct module *owner,
406 bool (*fn)(const struct symsearch *syms,
407 struct module *owner,
413 for (j = 0; j < arrsize; j++) {
414 if (fn(&arr[j], owner, data))
421 /* Returns true as soon as fn returns true, otherwise false. */
422 bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
423 struct module *owner,
428 static const struct symsearch arr[] = {
429 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
430 NOT_GPL_ONLY, false },
431 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
432 __start___kcrctab_gpl,
434 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
435 __start___kcrctab_gpl_future,
436 WILL_BE_GPL_ONLY, false },
437 #ifdef CONFIG_UNUSED_SYMBOLS
438 { __start___ksymtab_unused, __stop___ksymtab_unused,
439 __start___kcrctab_unused,
440 NOT_GPL_ONLY, true },
441 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
442 __start___kcrctab_unused_gpl,
447 module_assert_mutex_or_preempt();
449 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
452 list_for_each_entry_rcu(mod, &modules, list,
453 lockdep_is_held(&module_mutex)) {
454 struct symsearch arr[] = {
455 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
456 NOT_GPL_ONLY, false },
457 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
460 { mod->gpl_future_syms,
461 mod->gpl_future_syms + mod->num_gpl_future_syms,
462 mod->gpl_future_crcs,
463 WILL_BE_GPL_ONLY, false },
464 #ifdef CONFIG_UNUSED_SYMBOLS
466 mod->unused_syms + mod->num_unused_syms,
468 NOT_GPL_ONLY, true },
469 { mod->unused_gpl_syms,
470 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
471 mod->unused_gpl_crcs,
476 if (mod->state == MODULE_STATE_UNFORMED)
479 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
484 EXPORT_SYMBOL_GPL(each_symbol_section);
486 struct find_symbol_arg {
493 struct module *owner;
495 const struct kernel_symbol *sym;
498 static bool check_exported_symbol(const struct symsearch *syms,
499 struct module *owner,
500 unsigned int symnum, void *data)
502 struct find_symbol_arg *fsa = data;
505 if (syms->licence == GPL_ONLY)
507 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
508 pr_warn("Symbol %s is being used by a non-GPL module, "
509 "which will not be allowed in the future\n",
514 #ifdef CONFIG_UNUSED_SYMBOLS
515 if (syms->unused && fsa->warn) {
516 pr_warn("Symbol %s is marked as UNUSED, however this module is "
517 "using it.\n", fsa->name);
518 pr_warn("This symbol will go away in the future.\n");
519 pr_warn("Please evaluate if this is the right api to use and "
520 "if it really is, submit a report to the linux kernel "
521 "mailing list together with submitting your code for "
527 fsa->crc = symversion(syms->crcs, symnum);
528 fsa->sym = &syms->start[symnum];
532 static unsigned long kernel_symbol_value(const struct kernel_symbol *sym)
534 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
535 return (unsigned long)offset_to_ptr(&sym->value_offset);
541 static const char *kernel_symbol_name(const struct kernel_symbol *sym)
543 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
544 return offset_to_ptr(&sym->name_offset);
550 static const char *kernel_symbol_namespace(const struct kernel_symbol *sym)
552 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
553 if (!sym->namespace_offset)
555 return offset_to_ptr(&sym->namespace_offset);
557 return sym->namespace;
561 static int cmp_name(const void *name, const void *sym)
563 return strcmp(name, kernel_symbol_name(sym));
566 static bool find_exported_symbol_in_section(const struct symsearch *syms,
567 struct module *owner,
570 struct find_symbol_arg *fsa = data;
571 struct kernel_symbol *sym;
573 sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
574 sizeof(struct kernel_symbol), cmp_name);
576 if (sym != NULL && check_exported_symbol(syms, owner,
577 sym - syms->start, data))
583 /* Find an exported symbol and return it, along with, (optional) crc and
584 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
585 const struct kernel_symbol *find_symbol(const char *name,
586 struct module **owner,
591 struct find_symbol_arg fsa;
597 if (each_symbol_section(find_exported_symbol_in_section, &fsa)) {
605 pr_debug("Failed to find symbol %s\n", name);
608 EXPORT_SYMBOL_GPL(find_symbol);
611 * Search for module by name: must hold module_mutex (or preempt disabled
612 * for read-only access).
614 static struct module *find_module_all(const char *name, size_t len,
619 module_assert_mutex_or_preempt();
621 list_for_each_entry_rcu(mod, &modules, list,
622 lockdep_is_held(&module_mutex)) {
623 if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
625 if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
631 struct module *find_module(const char *name)
633 module_assert_mutex();
634 return find_module_all(name, strlen(name), false);
636 EXPORT_SYMBOL_GPL(find_module);
640 static inline void __percpu *mod_percpu(struct module *mod)
645 static int percpu_modalloc(struct module *mod, struct load_info *info)
647 Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
648 unsigned long align = pcpusec->sh_addralign;
650 if (!pcpusec->sh_size)
653 if (align > PAGE_SIZE) {
654 pr_warn("%s: per-cpu alignment %li > %li\n",
655 mod->name, align, PAGE_SIZE);
659 mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
661 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
662 mod->name, (unsigned long)pcpusec->sh_size);
665 mod->percpu_size = pcpusec->sh_size;
669 static void percpu_modfree(struct module *mod)
671 free_percpu(mod->percpu);
674 static unsigned int find_pcpusec(struct load_info *info)
676 return find_sec(info, ".data..percpu");
679 static void percpu_modcopy(struct module *mod,
680 const void *from, unsigned long size)
684 for_each_possible_cpu(cpu)
685 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
688 bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
695 list_for_each_entry_rcu(mod, &modules, list) {
696 if (mod->state == MODULE_STATE_UNFORMED)
698 if (!mod->percpu_size)
700 for_each_possible_cpu(cpu) {
701 void *start = per_cpu_ptr(mod->percpu, cpu);
702 void *va = (void *)addr;
704 if (va >= start && va < start + mod->percpu_size) {
706 *can_addr = (unsigned long) (va - start);
707 *can_addr += (unsigned long)
708 per_cpu_ptr(mod->percpu,
722 * is_module_percpu_address - test whether address is from module static percpu
723 * @addr: address to test
725 * Test whether @addr belongs to module static percpu area.
728 * %true if @addr is from module static percpu area
730 bool is_module_percpu_address(unsigned long addr)
732 return __is_module_percpu_address(addr, NULL);
735 #else /* ... !CONFIG_SMP */
737 static inline void __percpu *mod_percpu(struct module *mod)
741 static int percpu_modalloc(struct module *mod, struct load_info *info)
743 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
744 if (info->sechdrs[info->index.pcpu].sh_size != 0)
748 static inline void percpu_modfree(struct module *mod)
751 static unsigned int find_pcpusec(struct load_info *info)
755 static inline void percpu_modcopy(struct module *mod,
756 const void *from, unsigned long size)
758 /* pcpusec should be 0, and size of that section should be 0. */
761 bool is_module_percpu_address(unsigned long addr)
766 bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
771 #endif /* CONFIG_SMP */
773 #define MODINFO_ATTR(field) \
774 static void setup_modinfo_##field(struct module *mod, const char *s) \
776 mod->field = kstrdup(s, GFP_KERNEL); \
778 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
779 struct module_kobject *mk, char *buffer) \
781 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
783 static int modinfo_##field##_exists(struct module *mod) \
785 return mod->field != NULL; \
787 static void free_modinfo_##field(struct module *mod) \
792 static struct module_attribute modinfo_##field = { \
793 .attr = { .name = __stringify(field), .mode = 0444 }, \
794 .show = show_modinfo_##field, \
795 .setup = setup_modinfo_##field, \
796 .test = modinfo_##field##_exists, \
797 .free = free_modinfo_##field, \
800 MODINFO_ATTR(version);
801 MODINFO_ATTR(srcversion);
803 static char last_unloaded_module[MODULE_NAME_LEN+1];
805 #ifdef CONFIG_MODULE_UNLOAD
807 EXPORT_TRACEPOINT_SYMBOL(module_get);
809 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
810 #define MODULE_REF_BASE 1
812 /* Init the unload section of the module. */
813 static int module_unload_init(struct module *mod)
816 * Initialize reference counter to MODULE_REF_BASE.
817 * refcnt == 0 means module is going.
819 atomic_set(&mod->refcnt, MODULE_REF_BASE);
821 INIT_LIST_HEAD(&mod->source_list);
822 INIT_LIST_HEAD(&mod->target_list);
824 /* Hold reference count during initialization. */
825 atomic_inc(&mod->refcnt);
830 /* Does a already use b? */
831 static int already_uses(struct module *a, struct module *b)
833 struct module_use *use;
835 list_for_each_entry(use, &b->source_list, source_list) {
836 if (use->source == a) {
837 pr_debug("%s uses %s!\n", a->name, b->name);
841 pr_debug("%s does not use %s!\n", a->name, b->name);
847 * - we add 'a' as a "source", 'b' as a "target" of module use
848 * - the module_use is added to the list of 'b' sources (so
849 * 'b' can walk the list to see who sourced them), and of 'a'
850 * targets (so 'a' can see what modules it targets).
852 static int add_module_usage(struct module *a, struct module *b)
854 struct module_use *use;
856 pr_debug("Allocating new usage for %s.\n", a->name);
857 use = kmalloc(sizeof(*use), GFP_ATOMIC);
863 list_add(&use->source_list, &b->source_list);
864 list_add(&use->target_list, &a->target_list);
868 /* Module a uses b: caller needs module_mutex() */
869 int ref_module(struct module *a, struct module *b)
873 if (b == NULL || already_uses(a, b))
876 /* If module isn't available, we fail. */
877 err = strong_try_module_get(b);
881 err = add_module_usage(a, b);
888 EXPORT_SYMBOL_GPL(ref_module);
890 /* Clear the unload stuff of the module. */
891 static void module_unload_free(struct module *mod)
893 struct module_use *use, *tmp;
895 mutex_lock(&module_mutex);
896 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
897 struct module *i = use->target;
898 pr_debug("%s unusing %s\n", mod->name, i->name);
900 list_del(&use->source_list);
901 list_del(&use->target_list);
904 mutex_unlock(&module_mutex);
907 #ifdef CONFIG_MODULE_FORCE_UNLOAD
908 static inline int try_force_unload(unsigned int flags)
910 int ret = (flags & O_TRUNC);
912 add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
916 static inline int try_force_unload(unsigned int flags)
920 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
922 /* Try to release refcount of module, 0 means success. */
923 static int try_release_module_ref(struct module *mod)
927 /* Try to decrement refcnt which we set at loading */
928 ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
931 /* Someone can put this right now, recover with checking */
932 ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
937 static int try_stop_module(struct module *mod, int flags, int *forced)
939 /* If it's not unused, quit unless we're forcing. */
940 if (try_release_module_ref(mod) != 0) {
941 *forced = try_force_unload(flags);
946 /* Mark it as dying. */
947 mod->state = MODULE_STATE_GOING;
953 * module_refcount - return the refcount or -1 if unloading
955 * @mod: the module we're checking
958 * -1 if the module is in the process of unloading
959 * otherwise the number of references in the kernel to the module
961 int module_refcount(struct module *mod)
963 return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
965 EXPORT_SYMBOL(module_refcount);
967 /* This exists whether we can unload or not */
968 static void free_module(struct module *mod);
970 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
974 char name[MODULE_NAME_LEN];
977 if (!capable(CAP_SYS_MODULE) || modules_disabled)
980 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
982 name[MODULE_NAME_LEN-1] = '\0';
984 audit_log_kern_module(name);
986 if (mutex_lock_interruptible(&module_mutex) != 0)
989 mod = find_module(name);
995 if (!list_empty(&mod->source_list)) {
996 /* Other modules depend on us: get rid of them first. */
1001 /* Doing init or already dying? */
1002 if (mod->state != MODULE_STATE_LIVE) {
1003 /* FIXME: if (force), slam module count damn the torpedoes */
1004 pr_debug("%s already dying\n", mod->name);
1009 /* If it has an init func, it must have an exit func to unload */
1010 if (mod->init && !mod->exit) {
1011 forced = try_force_unload(flags);
1013 /* This module can't be removed */
1019 /* Stop the machine so refcounts can't move and disable module. */
1020 ret = try_stop_module(mod, flags, &forced);
1024 mutex_unlock(&module_mutex);
1025 /* Final destruction now no one is using it. */
1026 if (mod->exit != NULL)
1028 blocking_notifier_call_chain(&module_notify_list,
1029 MODULE_STATE_GOING, mod);
1030 klp_module_going(mod);
1031 ftrace_release_mod(mod);
1033 async_synchronize_full();
1035 /* Store the name of the last unloaded module for diagnostic purposes */
1036 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
1039 /* someone could wait for the module in add_unformed_module() */
1040 wake_up_all(&module_wq);
1043 mutex_unlock(&module_mutex);
1047 static inline void print_unload_info(struct seq_file *m, struct module *mod)
1049 struct module_use *use;
1050 int printed_something = 0;
1052 seq_printf(m, " %i ", module_refcount(mod));
1055 * Always include a trailing , so userspace can differentiate
1056 * between this and the old multi-field proc format.
1058 list_for_each_entry(use, &mod->source_list, source_list) {
1059 printed_something = 1;
1060 seq_printf(m, "%s,", use->source->name);
1063 if (mod->init != NULL && mod->exit == NULL) {
1064 printed_something = 1;
1065 seq_puts(m, "[permanent],");
1068 if (!printed_something)
1072 void __symbol_put(const char *symbol)
1074 struct module *owner;
1077 if (!find_symbol(symbol, &owner, NULL, true, false))
1082 EXPORT_SYMBOL(__symbol_put);
1084 /* Note this assumes addr is a function, which it currently always is. */
1085 void symbol_put_addr(void *addr)
1087 struct module *modaddr;
1088 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
1090 if (core_kernel_text(a))
1094 * Even though we hold a reference on the module; we still need to
1095 * disable preemption in order to safely traverse the data structure.
1098 modaddr = __module_text_address(a);
1100 module_put(modaddr);
1103 EXPORT_SYMBOL_GPL(symbol_put_addr);
1105 static ssize_t show_refcnt(struct module_attribute *mattr,
1106 struct module_kobject *mk, char *buffer)
1108 return sprintf(buffer, "%i\n", module_refcount(mk->mod));
1111 static struct module_attribute modinfo_refcnt =
1112 __ATTR(refcnt, 0444, show_refcnt, NULL);
1114 void __module_get(struct module *module)
1118 atomic_inc(&module->refcnt);
1119 trace_module_get(module, _RET_IP_);
1123 EXPORT_SYMBOL(__module_get);
1125 bool try_module_get(struct module *module)
1131 /* Note: here, we can fail to get a reference */
1132 if (likely(module_is_live(module) &&
1133 atomic_inc_not_zero(&module->refcnt) != 0))
1134 trace_module_get(module, _RET_IP_);
1142 EXPORT_SYMBOL(try_module_get);
1144 void module_put(struct module *module)
1150 ret = atomic_dec_if_positive(&module->refcnt);
1151 WARN_ON(ret < 0); /* Failed to put refcount */
1152 trace_module_put(module, _RET_IP_);
1156 EXPORT_SYMBOL(module_put);
1158 #else /* !CONFIG_MODULE_UNLOAD */
1159 static inline void print_unload_info(struct seq_file *m, struct module *mod)
1161 /* We don't know the usage count, or what modules are using. */
1162 seq_puts(m, " - -");
1165 static inline void module_unload_free(struct module *mod)
1169 int ref_module(struct module *a, struct module *b)
1171 return strong_try_module_get(b);
1173 EXPORT_SYMBOL_GPL(ref_module);
1175 static inline int module_unload_init(struct module *mod)
1179 #endif /* CONFIG_MODULE_UNLOAD */
1181 static size_t module_flags_taint(struct module *mod, char *buf)
1186 for (i = 0; i < TAINT_FLAGS_COUNT; i++) {
1187 if (taint_flags[i].module && test_bit(i, &mod->taints))
1188 buf[l++] = taint_flags[i].c_true;
1194 static ssize_t show_initstate(struct module_attribute *mattr,
1195 struct module_kobject *mk, char *buffer)
1197 const char *state = "unknown";
1199 switch (mk->mod->state) {
1200 case MODULE_STATE_LIVE:
1203 case MODULE_STATE_COMING:
1206 case MODULE_STATE_GOING:
1212 return sprintf(buffer, "%s\n", state);
1215 static struct module_attribute modinfo_initstate =
1216 __ATTR(initstate, 0444, show_initstate, NULL);
1218 static ssize_t store_uevent(struct module_attribute *mattr,
1219 struct module_kobject *mk,
1220 const char *buffer, size_t count)
1224 rc = kobject_synth_uevent(&mk->kobj, buffer, count);
1225 return rc ? rc : count;
1228 struct module_attribute module_uevent =
1229 __ATTR(uevent, 0200, NULL, store_uevent);
1231 static ssize_t show_coresize(struct module_attribute *mattr,
1232 struct module_kobject *mk, char *buffer)
1234 return sprintf(buffer, "%u\n", mk->mod->core_layout.size);
1237 static struct module_attribute modinfo_coresize =
1238 __ATTR(coresize, 0444, show_coresize, NULL);
1240 static ssize_t show_initsize(struct module_attribute *mattr,
1241 struct module_kobject *mk, char *buffer)
1243 return sprintf(buffer, "%u\n", mk->mod->init_layout.size);
1246 static struct module_attribute modinfo_initsize =
1247 __ATTR(initsize, 0444, show_initsize, NULL);
1249 static ssize_t show_taint(struct module_attribute *mattr,
1250 struct module_kobject *mk, char *buffer)
1254 l = module_flags_taint(mk->mod, buffer);
1259 static struct module_attribute modinfo_taint =
1260 __ATTR(taint, 0444, show_taint, NULL);
1262 static struct module_attribute *modinfo_attrs[] = {
1265 &modinfo_srcversion,
1270 #ifdef CONFIG_MODULE_UNLOAD
1276 static const char vermagic[] = VERMAGIC_STRING;
1278 static int try_to_force_load(struct module *mod, const char *reason)
1280 #ifdef CONFIG_MODULE_FORCE_LOAD
1281 if (!test_taint(TAINT_FORCED_MODULE))
1282 pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
1283 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
1290 #ifdef CONFIG_MODVERSIONS
1292 static u32 resolve_rel_crc(const s32 *crc)
1294 return *(u32 *)((void *)crc + *crc);
1297 static int check_version(const struct load_info *info,
1298 const char *symname,
1302 Elf_Shdr *sechdrs = info->sechdrs;
1303 unsigned int versindex = info->index.vers;
1304 unsigned int i, num_versions;
1305 struct modversion_info *versions;
1307 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1311 /* No versions at all? modprobe --force does this. */
1313 return try_to_force_load(mod, symname) == 0;
1315 versions = (void *) sechdrs[versindex].sh_addr;
1316 num_versions = sechdrs[versindex].sh_size
1317 / sizeof(struct modversion_info);
1319 for (i = 0; i < num_versions; i++) {
1322 if (strcmp(versions[i].name, symname) != 0)
1325 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS))
1326 crcval = resolve_rel_crc(crc);
1329 if (versions[i].crc == crcval)
1331 pr_debug("Found checksum %X vs module %lX\n",
1332 crcval, versions[i].crc);
1336 /* Broken toolchain. Warn once, then let it go.. */
1337 pr_warn_once("%s: no symbol version for %s\n", info->name, symname);
1341 pr_warn("%s: disagrees about version of symbol %s\n",
1342 info->name, symname);
1346 static inline int check_modstruct_version(const struct load_info *info,
1352 * Since this should be found in kernel (which can't be removed), no
1353 * locking is necessary -- use preempt_disable() to placate lockdep.
1356 if (!find_symbol("module_layout", NULL, &crc, true, false)) {
1361 return check_version(info, "module_layout", mod, crc);
1364 /* First part is kernel version, which we ignore if module has crcs. */
1365 static inline int same_magic(const char *amagic, const char *bmagic,
1369 amagic += strcspn(amagic, " ");
1370 bmagic += strcspn(bmagic, " ");
1372 return strcmp(amagic, bmagic) == 0;
1375 static inline int check_version(const struct load_info *info,
1376 const char *symname,
1383 static inline int check_modstruct_version(const struct load_info *info,
1389 static inline int same_magic(const char *amagic, const char *bmagic,
1392 return strcmp(amagic, bmagic) == 0;
1394 #endif /* CONFIG_MODVERSIONS */
1396 static char *get_modinfo(const struct load_info *info, const char *tag);
1397 static char *get_next_modinfo(const struct load_info *info, const char *tag,
1400 static int verify_namespace_is_imported(const struct load_info *info,
1401 const struct kernel_symbol *sym,
1404 const char *namespace;
1405 char *imported_namespace;
1407 namespace = kernel_symbol_namespace(sym);
1408 if (namespace && namespace[0]) {
1409 imported_namespace = get_modinfo(info, "import_ns");
1410 while (imported_namespace) {
1411 if (strcmp(namespace, imported_namespace) == 0)
1413 imported_namespace = get_next_modinfo(
1414 info, "import_ns", imported_namespace);
1416 #ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1421 "%s: module uses symbol (%s) from namespace %s, but does not import it.\n",
1422 mod->name, kernel_symbol_name(sym), namespace);
1423 #ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1431 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1432 static const struct kernel_symbol *resolve_symbol(struct module *mod,
1433 const struct load_info *info,
1437 struct module *owner;
1438 const struct kernel_symbol *sym;
1443 * The module_mutex should not be a heavily contended lock;
1444 * if we get the occasional sleep here, we'll go an extra iteration
1445 * in the wait_event_interruptible(), which is harmless.
1447 sched_annotate_sleep();
1448 mutex_lock(&module_mutex);
1449 sym = find_symbol(name, &owner, &crc,
1450 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1454 if (!check_version(info, name, mod, crc)) {
1455 sym = ERR_PTR(-EINVAL);
1459 err = verify_namespace_is_imported(info, sym, mod);
1465 err = ref_module(mod, owner);
1472 /* We must make copy under the lock if we failed to get ref. */
1473 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1475 mutex_unlock(&module_mutex);
1479 static const struct kernel_symbol *
1480 resolve_symbol_wait(struct module *mod,
1481 const struct load_info *info,
1484 const struct kernel_symbol *ksym;
1485 char owner[MODULE_NAME_LEN];
1487 if (wait_event_interruptible_timeout(module_wq,
1488 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1489 || PTR_ERR(ksym) != -EBUSY,
1491 pr_warn("%s: gave up waiting for init of module %s.\n",
1498 * /sys/module/foo/sections stuff
1499 * J. Corbet <corbet@lwn.net>
1503 #ifdef CONFIG_KALLSYMS
1504 static inline bool sect_empty(const Elf_Shdr *sect)
1506 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1509 struct module_sect_attr {
1510 struct module_attribute mattr;
1512 unsigned long address;
1515 struct module_sect_attrs {
1516 struct attribute_group grp;
1517 unsigned int nsections;
1518 struct module_sect_attr attrs[];
1521 static ssize_t module_sect_show(struct module_attribute *mattr,
1522 struct module_kobject *mk, char *buf)
1524 struct module_sect_attr *sattr =
1525 container_of(mattr, struct module_sect_attr, mattr);
1526 return sprintf(buf, "0x%px\n", kptr_restrict < 2 ?
1527 (void *)sattr->address : NULL);
1530 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1532 unsigned int section;
1534 for (section = 0; section < sect_attrs->nsections; section++)
1535 kfree(sect_attrs->attrs[section].name);
1539 static void add_sect_attrs(struct module *mod, const struct load_info *info)
1541 unsigned int nloaded = 0, i, size[2];
1542 struct module_sect_attrs *sect_attrs;
1543 struct module_sect_attr *sattr;
1544 struct attribute **gattr;
1546 /* Count loaded sections and allocate structures */
1547 for (i = 0; i < info->hdr->e_shnum; i++)
1548 if (!sect_empty(&info->sechdrs[i]))
1550 size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded),
1551 sizeof(sect_attrs->grp.attrs[0]));
1552 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1553 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1554 if (sect_attrs == NULL)
1557 /* Setup section attributes. */
1558 sect_attrs->grp.name = "sections";
1559 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1561 sect_attrs->nsections = 0;
1562 sattr = §_attrs->attrs[0];
1563 gattr = §_attrs->grp.attrs[0];
1564 for (i = 0; i < info->hdr->e_shnum; i++) {
1565 Elf_Shdr *sec = &info->sechdrs[i];
1566 if (sect_empty(sec))
1568 sattr->address = sec->sh_addr;
1569 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1571 if (sattr->name == NULL)
1573 sect_attrs->nsections++;
1574 sysfs_attr_init(&sattr->mattr.attr);
1575 sattr->mattr.show = module_sect_show;
1576 sattr->mattr.store = NULL;
1577 sattr->mattr.attr.name = sattr->name;
1578 sattr->mattr.attr.mode = S_IRUSR;
1579 *(gattr++) = &(sattr++)->mattr.attr;
1583 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1586 mod->sect_attrs = sect_attrs;
1589 free_sect_attrs(sect_attrs);
1592 static void remove_sect_attrs(struct module *mod)
1594 if (mod->sect_attrs) {
1595 sysfs_remove_group(&mod->mkobj.kobj,
1596 &mod->sect_attrs->grp);
1597 /* We are positive that no one is using any sect attrs
1598 * at this point. Deallocate immediately. */
1599 free_sect_attrs(mod->sect_attrs);
1600 mod->sect_attrs = NULL;
1605 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1608 struct module_notes_attrs {
1609 struct kobject *dir;
1611 struct bin_attribute attrs[];
1614 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1615 struct bin_attribute *bin_attr,
1616 char *buf, loff_t pos, size_t count)
1619 * The caller checked the pos and count against our size.
1621 memcpy(buf, bin_attr->private + pos, count);
1625 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1628 if (notes_attrs->dir) {
1630 sysfs_remove_bin_file(notes_attrs->dir,
1631 ¬es_attrs->attrs[i]);
1632 kobject_put(notes_attrs->dir);
1637 static void add_notes_attrs(struct module *mod, const struct load_info *info)
1639 unsigned int notes, loaded, i;
1640 struct module_notes_attrs *notes_attrs;
1641 struct bin_attribute *nattr;
1643 /* failed to create section attributes, so can't create notes */
1644 if (!mod->sect_attrs)
1647 /* Count notes sections and allocate structures. */
1649 for (i = 0; i < info->hdr->e_shnum; i++)
1650 if (!sect_empty(&info->sechdrs[i]) &&
1651 (info->sechdrs[i].sh_type == SHT_NOTE))
1657 notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes),
1659 if (notes_attrs == NULL)
1662 notes_attrs->notes = notes;
1663 nattr = ¬es_attrs->attrs[0];
1664 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1665 if (sect_empty(&info->sechdrs[i]))
1667 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1668 sysfs_bin_attr_init(nattr);
1669 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1670 nattr->attr.mode = S_IRUGO;
1671 nattr->size = info->sechdrs[i].sh_size;
1672 nattr->private = (void *) info->sechdrs[i].sh_addr;
1673 nattr->read = module_notes_read;
1679 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1680 if (!notes_attrs->dir)
1683 for (i = 0; i < notes; ++i)
1684 if (sysfs_create_bin_file(notes_attrs->dir,
1685 ¬es_attrs->attrs[i]))
1688 mod->notes_attrs = notes_attrs;
1692 free_notes_attrs(notes_attrs, i);
1695 static void remove_notes_attrs(struct module *mod)
1697 if (mod->notes_attrs)
1698 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1703 static inline void add_sect_attrs(struct module *mod,
1704 const struct load_info *info)
1708 static inline void remove_sect_attrs(struct module *mod)
1712 static inline void add_notes_attrs(struct module *mod,
1713 const struct load_info *info)
1717 static inline void remove_notes_attrs(struct module *mod)
1720 #endif /* CONFIG_KALLSYMS */
1722 static void del_usage_links(struct module *mod)
1724 #ifdef CONFIG_MODULE_UNLOAD
1725 struct module_use *use;
1727 mutex_lock(&module_mutex);
1728 list_for_each_entry(use, &mod->target_list, target_list)
1729 sysfs_remove_link(use->target->holders_dir, mod->name);
1730 mutex_unlock(&module_mutex);
1734 static int add_usage_links(struct module *mod)
1737 #ifdef CONFIG_MODULE_UNLOAD
1738 struct module_use *use;
1740 mutex_lock(&module_mutex);
1741 list_for_each_entry(use, &mod->target_list, target_list) {
1742 ret = sysfs_create_link(use->target->holders_dir,
1743 &mod->mkobj.kobj, mod->name);
1747 mutex_unlock(&module_mutex);
1749 del_usage_links(mod);
1754 static void module_remove_modinfo_attrs(struct module *mod, int end);
1756 static int module_add_modinfo_attrs(struct module *mod)
1758 struct module_attribute *attr;
1759 struct module_attribute *temp_attr;
1763 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1764 (ARRAY_SIZE(modinfo_attrs) + 1)),
1766 if (!mod->modinfo_attrs)
1769 temp_attr = mod->modinfo_attrs;
1770 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1771 if (!attr->test || attr->test(mod)) {
1772 memcpy(temp_attr, attr, sizeof(*temp_attr));
1773 sysfs_attr_init(&temp_attr->attr);
1774 error = sysfs_create_file(&mod->mkobj.kobj,
1786 module_remove_modinfo_attrs(mod, --i);
1788 kfree(mod->modinfo_attrs);
1792 static void module_remove_modinfo_attrs(struct module *mod, int end)
1794 struct module_attribute *attr;
1797 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1798 if (end >= 0 && i > end)
1800 /* pick a field to test for end of list */
1801 if (!attr->attr.name)
1803 sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
1807 kfree(mod->modinfo_attrs);
1810 static void mod_kobject_put(struct module *mod)
1812 DECLARE_COMPLETION_ONSTACK(c);
1813 mod->mkobj.kobj_completion = &c;
1814 kobject_put(&mod->mkobj.kobj);
1815 wait_for_completion(&c);
1818 static int mod_sysfs_init(struct module *mod)
1821 struct kobject *kobj;
1823 if (!module_sysfs_initialized) {
1824 pr_err("%s: module sysfs not initialized\n", mod->name);
1829 kobj = kset_find_obj(module_kset, mod->name);
1831 pr_err("%s: module is already loaded\n", mod->name);
1837 mod->mkobj.mod = mod;
1839 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1840 mod->mkobj.kobj.kset = module_kset;
1841 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1844 mod_kobject_put(mod);
1846 /* delay uevent until full sysfs population */
1851 static int mod_sysfs_setup(struct module *mod,
1852 const struct load_info *info,
1853 struct kernel_param *kparam,
1854 unsigned int num_params)
1858 err = mod_sysfs_init(mod);
1862 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1863 if (!mod->holders_dir) {
1868 err = module_param_sysfs_setup(mod, kparam, num_params);
1870 goto out_unreg_holders;
1872 err = module_add_modinfo_attrs(mod);
1874 goto out_unreg_param;
1876 err = add_usage_links(mod);
1878 goto out_unreg_modinfo_attrs;
1880 add_sect_attrs(mod, info);
1881 add_notes_attrs(mod, info);
1883 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1886 out_unreg_modinfo_attrs:
1887 module_remove_modinfo_attrs(mod, -1);
1889 module_param_sysfs_remove(mod);
1891 kobject_put(mod->holders_dir);
1893 mod_kobject_put(mod);
1898 static void mod_sysfs_fini(struct module *mod)
1900 remove_notes_attrs(mod);
1901 remove_sect_attrs(mod);
1902 mod_kobject_put(mod);
1905 static void init_param_lock(struct module *mod)
1907 mutex_init(&mod->param_lock);
1909 #else /* !CONFIG_SYSFS */
1911 static int mod_sysfs_setup(struct module *mod,
1912 const struct load_info *info,
1913 struct kernel_param *kparam,
1914 unsigned int num_params)
1919 static void mod_sysfs_fini(struct module *mod)
1923 static void module_remove_modinfo_attrs(struct module *mod, int end)
1927 static void del_usage_links(struct module *mod)
1931 static void init_param_lock(struct module *mod)
1934 #endif /* CONFIG_SYSFS */
1936 static void mod_sysfs_teardown(struct module *mod)
1938 del_usage_links(mod);
1939 module_remove_modinfo_attrs(mod, -1);
1940 module_param_sysfs_remove(mod);
1941 kobject_put(mod->mkobj.drivers_dir);
1942 kobject_put(mod->holders_dir);
1943 mod_sysfs_fini(mod);
1946 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
1948 * LKM RO/NX protection: protect module's text/ro-data
1949 * from modification and any data from execution.
1951 * General layout of module is:
1952 * [text] [read-only-data] [ro-after-init] [writable data]
1953 * text_size -----^ ^ ^ ^
1954 * ro_size ------------------------| | |
1955 * ro_after_init_size -----------------------------| |
1956 * size -----------------------------------------------------------|
1958 * These values are always page-aligned (as is base)
1960 static void frob_text(const struct module_layout *layout,
1961 int (*set_memory)(unsigned long start, int num_pages))
1963 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1964 BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
1965 set_memory((unsigned long)layout->base,
1966 layout->text_size >> PAGE_SHIFT);
1969 #ifdef CONFIG_STRICT_MODULE_RWX
1970 static void frob_rodata(const struct module_layout *layout,
1971 int (*set_memory)(unsigned long start, int num_pages))
1973 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1974 BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
1975 BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
1976 set_memory((unsigned long)layout->base + layout->text_size,
1977 (layout->ro_size - layout->text_size) >> PAGE_SHIFT);
1980 static void frob_ro_after_init(const struct module_layout *layout,
1981 int (*set_memory)(unsigned long start, int num_pages))
1983 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1984 BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
1985 BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1));
1986 set_memory((unsigned long)layout->base + layout->ro_size,
1987 (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT);
1990 static void frob_writable_data(const struct module_layout *layout,
1991 int (*set_memory)(unsigned long start, int num_pages))
1993 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1994 BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1));
1995 BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1));
1996 set_memory((unsigned long)layout->base + layout->ro_after_init_size,
1997 (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT);
2000 /* livepatching wants to disable read-only so it can frob module. */
2001 void module_disable_ro(const struct module *mod)
2003 if (!rodata_enabled)
2006 frob_text(&mod->core_layout, set_memory_rw);
2007 frob_rodata(&mod->core_layout, set_memory_rw);
2008 frob_ro_after_init(&mod->core_layout, set_memory_rw);
2009 frob_text(&mod->init_layout, set_memory_rw);
2010 frob_rodata(&mod->init_layout, set_memory_rw);
2013 void module_enable_ro(const struct module *mod, bool after_init)
2015 if (!rodata_enabled)
2018 set_vm_flush_reset_perms(mod->core_layout.base);
2019 set_vm_flush_reset_perms(mod->init_layout.base);
2020 frob_text(&mod->core_layout, set_memory_ro);
2022 frob_rodata(&mod->core_layout, set_memory_ro);
2023 frob_text(&mod->init_layout, set_memory_ro);
2024 frob_rodata(&mod->init_layout, set_memory_ro);
2027 frob_ro_after_init(&mod->core_layout, set_memory_ro);
2030 static void module_enable_nx(const struct module *mod)
2032 frob_rodata(&mod->core_layout, set_memory_nx);
2033 frob_ro_after_init(&mod->core_layout, set_memory_nx);
2034 frob_writable_data(&mod->core_layout, set_memory_nx);
2035 frob_rodata(&mod->init_layout, set_memory_nx);
2036 frob_writable_data(&mod->init_layout, set_memory_nx);
2039 #else /* !CONFIG_STRICT_MODULE_RWX */
2040 static void module_enable_nx(const struct module *mod) { }
2041 #endif /* CONFIG_STRICT_MODULE_RWX */
2042 static void module_enable_x(const struct module *mod)
2044 frob_text(&mod->core_layout, set_memory_x);
2045 frob_text(&mod->init_layout, set_memory_x);
2047 #else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2048 static void module_enable_nx(const struct module *mod) { }
2049 static void module_enable_x(const struct module *mod) { }
2050 #endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2053 #ifdef CONFIG_LIVEPATCH
2055 * Persist Elf information about a module. Copy the Elf header,
2056 * section header table, section string table, and symtab section
2057 * index from info to mod->klp_info.
2059 static int copy_module_elf(struct module *mod, struct load_info *info)
2061 unsigned int size, symndx;
2064 size = sizeof(*mod->klp_info);
2065 mod->klp_info = kmalloc(size, GFP_KERNEL);
2066 if (mod->klp_info == NULL)
2070 size = sizeof(mod->klp_info->hdr);
2071 memcpy(&mod->klp_info->hdr, info->hdr, size);
2073 /* Elf section header table */
2074 size = sizeof(*info->sechdrs) * info->hdr->e_shnum;
2075 mod->klp_info->sechdrs = kmemdup(info->sechdrs, size, GFP_KERNEL);
2076 if (mod->klp_info->sechdrs == NULL) {
2081 /* Elf section name string table */
2082 size = info->sechdrs[info->hdr->e_shstrndx].sh_size;
2083 mod->klp_info->secstrings = kmemdup(info->secstrings, size, GFP_KERNEL);
2084 if (mod->klp_info->secstrings == NULL) {
2089 /* Elf symbol section index */
2090 symndx = info->index.sym;
2091 mod->klp_info->symndx = symndx;
2094 * For livepatch modules, core_kallsyms.symtab is a complete
2095 * copy of the original symbol table. Adjust sh_addr to point
2096 * to core_kallsyms.symtab since the copy of the symtab in module
2097 * init memory is freed at the end of do_init_module().
2099 mod->klp_info->sechdrs[symndx].sh_addr = \
2100 (unsigned long) mod->core_kallsyms.symtab;
2105 kfree(mod->klp_info->sechdrs);
2107 kfree(mod->klp_info);
2111 static void free_module_elf(struct module *mod)
2113 kfree(mod->klp_info->sechdrs);
2114 kfree(mod->klp_info->secstrings);
2115 kfree(mod->klp_info);
2117 #else /* !CONFIG_LIVEPATCH */
2118 static int copy_module_elf(struct module *mod, struct load_info *info)
2123 static void free_module_elf(struct module *mod)
2126 #endif /* CONFIG_LIVEPATCH */
2128 void __weak module_memfree(void *module_region)
2131 * This memory may be RO, and freeing RO memory in an interrupt is not
2132 * supported by vmalloc.
2134 WARN_ON(in_interrupt());
2135 vfree(module_region);
2138 void __weak module_arch_cleanup(struct module *mod)
2142 void __weak module_arch_freeing_init(struct module *mod)
2146 /* Free a module, remove from lists, etc. */
2147 static void free_module(struct module *mod)
2149 trace_module_free(mod);
2151 mod_sysfs_teardown(mod);
2153 /* We leave it in list to prevent duplicate loads, but make sure
2154 * that noone uses it while it's being deconstructed. */
2155 mutex_lock(&module_mutex);
2156 mod->state = MODULE_STATE_UNFORMED;
2157 mutex_unlock(&module_mutex);
2159 /* Remove dynamic debug info */
2160 ddebug_remove_module(mod->name);
2162 /* Arch-specific cleanup. */
2163 module_arch_cleanup(mod);
2165 /* Module unload stuff */
2166 module_unload_free(mod);
2168 /* Free any allocated parameters. */
2169 destroy_params(mod->kp, mod->num_kp);
2171 if (is_livepatch_module(mod))
2172 free_module_elf(mod);
2174 /* Now we can delete it from the lists */
2175 mutex_lock(&module_mutex);
2176 /* Unlink carefully: kallsyms could be walking list. */
2177 list_del_rcu(&mod->list);
2178 mod_tree_remove(mod);
2179 /* Remove this module from bug list, this uses list_del_rcu */
2180 module_bug_cleanup(mod);
2181 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2183 mutex_unlock(&module_mutex);
2185 /* This may be empty, but that's OK */
2186 module_arch_freeing_init(mod);
2187 module_memfree(mod->init_layout.base);
2189 percpu_modfree(mod);
2191 /* Free lock-classes; relies on the preceding sync_rcu(). */
2192 lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
2194 /* Finally, free the core (containing the module structure) */
2195 module_memfree(mod->core_layout.base);
2198 void *__symbol_get(const char *symbol)
2200 struct module *owner;
2201 const struct kernel_symbol *sym;
2204 sym = find_symbol(symbol, &owner, NULL, true, true);
2205 if (sym && strong_try_module_get(owner))
2209 return sym ? (void *)kernel_symbol_value(sym) : NULL;
2211 EXPORT_SYMBOL_GPL(__symbol_get);
2214 * Ensure that an exported symbol [global namespace] does not already exist
2215 * in the kernel or in some other module's exported symbol table.
2217 * You must hold the module_mutex.
2219 static int verify_exported_symbols(struct module *mod)
2222 struct module *owner;
2223 const struct kernel_symbol *s;
2225 const struct kernel_symbol *sym;
2228 { mod->syms, mod->num_syms },
2229 { mod->gpl_syms, mod->num_gpl_syms },
2230 { mod->gpl_future_syms, mod->num_gpl_future_syms },
2231 #ifdef CONFIG_UNUSED_SYMBOLS
2232 { mod->unused_syms, mod->num_unused_syms },
2233 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
2237 for (i = 0; i < ARRAY_SIZE(arr); i++) {
2238 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
2239 if (find_symbol(kernel_symbol_name(s), &owner, NULL,
2241 pr_err("%s: exports duplicate symbol %s"
2243 mod->name, kernel_symbol_name(s),
2244 module_name(owner));
2252 /* Change all symbols so that st_value encodes the pointer directly. */
2253 static int simplify_symbols(struct module *mod, const struct load_info *info)
2255 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2256 Elf_Sym *sym = (void *)symsec->sh_addr;
2257 unsigned long secbase;
2260 const struct kernel_symbol *ksym;
2262 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
2263 const char *name = info->strtab + sym[i].st_name;
2265 switch (sym[i].st_shndx) {
2267 /* Ignore common symbols */
2268 if (!strncmp(name, "__gnu_lto", 9))
2271 /* We compiled with -fno-common. These are not
2272 supposed to happen. */
2273 pr_debug("Common symbol: %s\n", name);
2274 pr_warn("%s: please compile with -fno-common\n",
2280 /* Don't need to do anything */
2281 pr_debug("Absolute symbol: 0x%08lx\n",
2282 (long)sym[i].st_value);
2286 /* Livepatch symbols are resolved by livepatch */
2290 ksym = resolve_symbol_wait(mod, info, name);
2291 /* Ok if resolved. */
2292 if (ksym && !IS_ERR(ksym)) {
2293 sym[i].st_value = kernel_symbol_value(ksym);
2298 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
2301 ret = PTR_ERR(ksym) ?: -ENOENT;
2302 pr_warn("%s: Unknown symbol %s (err %d)\n",
2303 mod->name, name, ret);
2307 /* Divert to percpu allocation if a percpu var. */
2308 if (sym[i].st_shndx == info->index.pcpu)
2309 secbase = (unsigned long)mod_percpu(mod);
2311 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
2312 sym[i].st_value += secbase;
2320 static int apply_relocations(struct module *mod, const struct load_info *info)
2325 /* Now do relocations. */
2326 for (i = 1; i < info->hdr->e_shnum; i++) {
2327 unsigned int infosec = info->sechdrs[i].sh_info;
2329 /* Not a valid relocation section? */
2330 if (infosec >= info->hdr->e_shnum)
2333 /* Don't bother with non-allocated sections */
2334 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
2337 /* Livepatch relocation sections are applied by livepatch */
2338 if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH)
2341 if (info->sechdrs[i].sh_type == SHT_REL)
2342 err = apply_relocate(info->sechdrs, info->strtab,
2343 info->index.sym, i, mod);
2344 else if (info->sechdrs[i].sh_type == SHT_RELA)
2345 err = apply_relocate_add(info->sechdrs, info->strtab,
2346 info->index.sym, i, mod);
2353 /* Additional bytes needed by arch in front of individual sections */
2354 unsigned int __weak arch_mod_section_prepend(struct module *mod,
2355 unsigned int section)
2357 /* default implementation just returns zero */
2361 /* Update size with this section: return offset. */
2362 static long get_offset(struct module *mod, unsigned int *size,
2363 Elf_Shdr *sechdr, unsigned int section)
2367 *size += arch_mod_section_prepend(mod, section);
2368 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2369 *size = ret + sechdr->sh_size;
2373 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2374 might -- code, read-only data, read-write data, small data. Tally
2375 sizes, and place the offsets into sh_entsize fields: high bit means it
2377 static void layout_sections(struct module *mod, struct load_info *info)
2379 static unsigned long const masks[][2] = {
2380 /* NOTE: all executable code must be the first section
2381 * in this array; otherwise modify the text_size
2382 * finder in the two loops below */
2383 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2384 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
2385 { SHF_RO_AFTER_INIT | SHF_ALLOC, ARCH_SHF_SMALL },
2386 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2387 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2391 for (i = 0; i < info->hdr->e_shnum; i++)
2392 info->sechdrs[i].sh_entsize = ~0UL;
2394 pr_debug("Core section allocation order:\n");
2395 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2396 for (i = 0; i < info->hdr->e_shnum; ++i) {
2397 Elf_Shdr *s = &info->sechdrs[i];
2398 const char *sname = info->secstrings + s->sh_name;
2400 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2401 || (s->sh_flags & masks[m][1])
2402 || s->sh_entsize != ~0UL
2403 || module_init_section(sname))
2405 s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i);
2406 pr_debug("\t%s\n", sname);
2409 case 0: /* executable */
2410 mod->core_layout.size = debug_align(mod->core_layout.size);
2411 mod->core_layout.text_size = mod->core_layout.size;
2413 case 1: /* RO: text and ro-data */
2414 mod->core_layout.size = debug_align(mod->core_layout.size);
2415 mod->core_layout.ro_size = mod->core_layout.size;
2417 case 2: /* RO after init */
2418 mod->core_layout.size = debug_align(mod->core_layout.size);
2419 mod->core_layout.ro_after_init_size = mod->core_layout.size;
2421 case 4: /* whole core */
2422 mod->core_layout.size = debug_align(mod->core_layout.size);
2427 pr_debug("Init section allocation order:\n");
2428 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2429 for (i = 0; i < info->hdr->e_shnum; ++i) {
2430 Elf_Shdr *s = &info->sechdrs[i];
2431 const char *sname = info->secstrings + s->sh_name;
2433 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2434 || (s->sh_flags & masks[m][1])
2435 || s->sh_entsize != ~0UL
2436 || !module_init_section(sname))
2438 s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i)
2439 | INIT_OFFSET_MASK);
2440 pr_debug("\t%s\n", sname);
2443 case 0: /* executable */
2444 mod->init_layout.size = debug_align(mod->init_layout.size);
2445 mod->init_layout.text_size = mod->init_layout.size;
2447 case 1: /* RO: text and ro-data */
2448 mod->init_layout.size = debug_align(mod->init_layout.size);
2449 mod->init_layout.ro_size = mod->init_layout.size;
2453 * RO after init doesn't apply to init_layout (only
2454 * core_layout), so it just takes the value of ro_size.
2456 mod->init_layout.ro_after_init_size = mod->init_layout.ro_size;
2458 case 4: /* whole init */
2459 mod->init_layout.size = debug_align(mod->init_layout.size);
2465 static void set_license(struct module *mod, const char *license)
2468 license = "unspecified";
2470 if (!license_is_gpl_compatible(license)) {
2471 if (!test_taint(TAINT_PROPRIETARY_MODULE))
2472 pr_warn("%s: module license '%s' taints kernel.\n",
2473 mod->name, license);
2474 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2475 LOCKDEP_NOW_UNRELIABLE);
2479 /* Parse tag=value strings from .modinfo section */
2480 static char *next_string(char *string, unsigned long *secsize)
2482 /* Skip non-zero chars */
2485 if ((*secsize)-- <= 1)
2489 /* Skip any zero padding. */
2490 while (!string[0]) {
2492 if ((*secsize)-- <= 1)
2498 static char *get_next_modinfo(const struct load_info *info, const char *tag,
2502 unsigned int taglen = strlen(tag);
2503 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2504 unsigned long size = infosec->sh_size;
2507 * get_modinfo() calls made before rewrite_section_headers()
2508 * must use sh_offset, as sh_addr isn't set!
2510 char *modinfo = (char *)info->hdr + infosec->sh_offset;
2513 size -= prev - modinfo;
2514 modinfo = next_string(prev, &size);
2517 for (p = modinfo; p; p = next_string(p, &size)) {
2518 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2519 return p + taglen + 1;
2524 static char *get_modinfo(const struct load_info *info, const char *tag)
2526 return get_next_modinfo(info, tag, NULL);
2529 static void setup_modinfo(struct module *mod, struct load_info *info)
2531 struct module_attribute *attr;
2534 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2536 attr->setup(mod, get_modinfo(info, attr->attr.name));
2540 static void free_modinfo(struct module *mod)
2542 struct module_attribute *attr;
2545 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2551 #ifdef CONFIG_KALLSYMS
2553 /* Lookup exported symbol in given range of kernel_symbols */
2554 static const struct kernel_symbol *lookup_exported_symbol(const char *name,
2555 const struct kernel_symbol *start,
2556 const struct kernel_symbol *stop)
2558 return bsearch(name, start, stop - start,
2559 sizeof(struct kernel_symbol), cmp_name);
2562 static int is_exported(const char *name, unsigned long value,
2563 const struct module *mod)
2565 const struct kernel_symbol *ks;
2567 ks = lookup_exported_symbol(name, __start___ksymtab, __stop___ksymtab);
2569 ks = lookup_exported_symbol(name, mod->syms, mod->syms + mod->num_syms);
2571 return ks != NULL && kernel_symbol_value(ks) == value;
2575 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
2577 const Elf_Shdr *sechdrs = info->sechdrs;
2579 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2580 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2585 if (sym->st_shndx == SHN_UNDEF)
2587 if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu)
2589 if (sym->st_shndx >= SHN_LORESERVE)
2591 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2593 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2594 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2595 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2597 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2602 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2603 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2608 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2615 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
2616 unsigned int shnum, unsigned int pcpundx)
2618 const Elf_Shdr *sec;
2620 if (src->st_shndx == SHN_UNDEF
2621 || src->st_shndx >= shnum
2625 #ifdef CONFIG_KALLSYMS_ALL
2626 if (src->st_shndx == pcpundx)
2630 sec = sechdrs + src->st_shndx;
2631 if (!(sec->sh_flags & SHF_ALLOC)
2632 #ifndef CONFIG_KALLSYMS_ALL
2633 || !(sec->sh_flags & SHF_EXECINSTR)
2635 || (sec->sh_entsize & INIT_OFFSET_MASK))
2642 * We only allocate and copy the strings needed by the parts of symtab
2643 * we keep. This is simple, but has the effect of making multiple
2644 * copies of duplicates. We could be more sophisticated, see
2645 * linux-kernel thread starting with
2646 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2648 static void layout_symtab(struct module *mod, struct load_info *info)
2650 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2651 Elf_Shdr *strsect = info->sechdrs + info->index.str;
2653 unsigned int i, nsrc, ndst, strtab_size = 0;
2655 /* Put symbol section at end of init part of module. */
2656 symsect->sh_flags |= SHF_ALLOC;
2657 symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect,
2658 info->index.sym) | INIT_OFFSET_MASK;
2659 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
2661 src = (void *)info->hdr + symsect->sh_offset;
2662 nsrc = symsect->sh_size / sizeof(*src);
2664 /* Compute total space required for the core symbols' strtab. */
2665 for (ndst = i = 0; i < nsrc; i++) {
2666 if (i == 0 || is_livepatch_module(mod) ||
2667 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
2668 info->index.pcpu)) {
2669 strtab_size += strlen(&info->strtab[src[i].st_name])+1;
2674 /* Append room for core symbols at end of core part. */
2675 info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1);
2676 info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym);
2677 mod->core_layout.size += strtab_size;
2678 info->core_typeoffs = mod->core_layout.size;
2679 mod->core_layout.size += ndst * sizeof(char);
2680 mod->core_layout.size = debug_align(mod->core_layout.size);
2682 /* Put string table section at end of init part of module. */
2683 strsect->sh_flags |= SHF_ALLOC;
2684 strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect,
2685 info->index.str) | INIT_OFFSET_MASK;
2686 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
2688 /* We'll tack temporary mod_kallsyms on the end. */
2689 mod->init_layout.size = ALIGN(mod->init_layout.size,
2690 __alignof__(struct mod_kallsyms));
2691 info->mod_kallsyms_init_off = mod->init_layout.size;
2692 mod->init_layout.size += sizeof(struct mod_kallsyms);
2693 info->init_typeoffs = mod->init_layout.size;
2694 mod->init_layout.size += nsrc * sizeof(char);
2695 mod->init_layout.size = debug_align(mod->init_layout.size);
2699 * We use the full symtab and strtab which layout_symtab arranged to
2700 * be appended to the init section. Later we switch to the cut-down
2703 static void add_kallsyms(struct module *mod, const struct load_info *info)
2705 unsigned int i, ndst;
2709 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2711 /* Set up to point into init section. */
2712 mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off;
2714 mod->kallsyms->symtab = (void *)symsec->sh_addr;
2715 mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2716 /* Make sure we get permanent strtab: don't use info->strtab. */
2717 mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2718 mod->kallsyms->typetab = mod->init_layout.base + info->init_typeoffs;
2721 * Now populate the cut down core kallsyms for after init
2722 * and set types up while we still have access to sections.
2724 mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs;
2725 mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs;
2726 mod->core_kallsyms.typetab = mod->core_layout.base + info->core_typeoffs;
2727 src = mod->kallsyms->symtab;
2728 for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) {
2729 mod->kallsyms->typetab[i] = elf_type(src + i, info);
2730 if (i == 0 || is_livepatch_module(mod) ||
2731 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
2732 info->index.pcpu)) {
2733 mod->core_kallsyms.typetab[ndst] =
2734 mod->kallsyms->typetab[i];
2736 dst[ndst++].st_name = s - mod->core_kallsyms.strtab;
2737 s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name],
2741 mod->core_kallsyms.num_symtab = ndst;
2744 static inline void layout_symtab(struct module *mod, struct load_info *info)
2748 static void add_kallsyms(struct module *mod, const struct load_info *info)
2751 #endif /* CONFIG_KALLSYMS */
2753 static void dynamic_debug_setup(struct module *mod, struct _ddebug *debug, unsigned int num)
2757 ddebug_add_module(debug, num, mod->name);
2760 static void dynamic_debug_remove(struct module *mod, struct _ddebug *debug)
2763 ddebug_remove_module(mod->name);
2766 void * __weak module_alloc(unsigned long size)
2768 return vmalloc_exec(size);
2771 bool __weak module_init_section(const char *name)
2773 return strstarts(name, ".init");
2776 bool __weak module_exit_section(const char *name)
2778 return strstarts(name, ".exit");
2781 #ifdef CONFIG_DEBUG_KMEMLEAK
2782 static void kmemleak_load_module(const struct module *mod,
2783 const struct load_info *info)
2787 /* only scan the sections containing data */
2788 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2790 for (i = 1; i < info->hdr->e_shnum; i++) {
2791 /* Scan all writable sections that's not executable */
2792 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
2793 !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
2794 (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
2797 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2798 info->sechdrs[i].sh_size, GFP_KERNEL);
2802 static inline void kmemleak_load_module(const struct module *mod,
2803 const struct load_info *info)
2808 #ifdef CONFIG_MODULE_SIG
2809 static int module_sig_check(struct load_info *info, int flags)
2812 const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2814 const void *mod = info->hdr;
2817 * Require flags == 0, as a module with version information
2818 * removed is no longer the module that was signed
2821 info->len > markerlen &&
2822 memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
2823 /* We truncate the module to discard the signature */
2824 info->len -= markerlen;
2825 err = mod_verify_sig(mod, info);
2830 info->sig_ok = true;
2833 /* We don't permit modules to be loaded into trusted kernels
2834 * without a valid signature on them, but if we're not
2835 * enforcing, certain errors are non-fatal.
2838 reason = "Loading of unsigned module";
2841 reason = "Loading of module with unsupported crypto";
2844 reason = "Loading of module with unavailable key";
2846 if (is_module_sig_enforced()) {
2847 pr_notice("%s: %s is rejected\n", info->name, reason);
2848 return -EKEYREJECTED;
2851 return security_locked_down(LOCKDOWN_MODULE_SIGNATURE);
2853 /* All other errors are fatal, including nomem, unparseable
2854 * signatures and signature check failures - even if signatures
2861 #else /* !CONFIG_MODULE_SIG */
2862 static int module_sig_check(struct load_info *info, int flags)
2866 #endif /* !CONFIG_MODULE_SIG */
2868 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2869 static int elf_header_check(struct load_info *info)
2871 if (info->len < sizeof(*(info->hdr)))
2874 if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2875 || info->hdr->e_type != ET_REL
2876 || !elf_check_arch(info->hdr)
2877 || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2880 if (info->hdr->e_shoff >= info->len
2881 || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2882 info->len - info->hdr->e_shoff))
2888 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2890 static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len)
2893 unsigned long n = min(len, COPY_CHUNK_SIZE);
2895 if (copy_from_user(dst, usrc, n) != 0)
2905 #ifdef CONFIG_LIVEPATCH
2906 static int check_modinfo_livepatch(struct module *mod, struct load_info *info)
2908 if (get_modinfo(info, "livepatch")) {
2910 add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK);
2911 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2917 #else /* !CONFIG_LIVEPATCH */
2918 static int check_modinfo_livepatch(struct module *mod, struct load_info *info)
2920 if (get_modinfo(info, "livepatch")) {
2921 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2928 #endif /* CONFIG_LIVEPATCH */
2930 static void check_modinfo_retpoline(struct module *mod, struct load_info *info)
2932 if (retpoline_module_ok(get_modinfo(info, "retpoline")))
2935 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
2939 /* Sets info->hdr and info->len. */
2940 static int copy_module_from_user(const void __user *umod, unsigned long len,
2941 struct load_info *info)
2946 if (info->len < sizeof(*(info->hdr)))
2949 err = security_kernel_load_data(LOADING_MODULE);
2953 /* Suck in entire file: we'll want most of it. */
2954 info->hdr = __vmalloc(info->len, GFP_KERNEL | __GFP_NOWARN);
2958 if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
2966 static void free_copy(struct load_info *info)
2971 static int rewrite_section_headers(struct load_info *info, int flags)
2975 /* This should always be true, but let's be sure. */
2976 info->sechdrs[0].sh_addr = 0;
2978 for (i = 1; i < info->hdr->e_shnum; i++) {
2979 Elf_Shdr *shdr = &info->sechdrs[i];
2980 if (shdr->sh_type != SHT_NOBITS
2981 && info->len < shdr->sh_offset + shdr->sh_size) {
2982 pr_err("Module len %lu truncated\n", info->len);
2986 /* Mark all sections sh_addr with their address in the
2988 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2990 #ifndef CONFIG_MODULE_UNLOAD
2991 /* Don't load .exit sections */
2992 if (module_exit_section(info->secstrings+shdr->sh_name))
2993 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2997 /* Track but don't keep modinfo and version sections. */
2998 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2999 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
3005 * Set up our basic convenience variables (pointers to section headers,
3006 * search for module section index etc), and do some basic section
3009 * Set info->mod to the temporary copy of the module in info->hdr. The final one
3010 * will be allocated in move_module().
3012 static int setup_load_info(struct load_info *info, int flags)
3016 /* Set up the convenience variables */
3017 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
3018 info->secstrings = (void *)info->hdr
3019 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
3021 /* Try to find a name early so we can log errors with a module name */
3022 info->index.info = find_sec(info, ".modinfo");
3023 if (info->index.info)
3024 info->name = get_modinfo(info, "name");
3026 /* Find internal symbols and strings. */
3027 for (i = 1; i < info->hdr->e_shnum; i++) {
3028 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
3029 info->index.sym = i;
3030 info->index.str = info->sechdrs[i].sh_link;
3031 info->strtab = (char *)info->hdr
3032 + info->sechdrs[info->index.str].sh_offset;
3037 if (info->index.sym == 0) {
3038 pr_warn("%s: module has no symbols (stripped?)\n",
3039 info->name ?: "(missing .modinfo section or name field)");
3043 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
3044 if (!info->index.mod) {
3045 pr_warn("%s: No module found in object\n",
3046 info->name ?: "(missing .modinfo section or name field)");
3049 /* This is temporary: point mod into copy of data. */
3050 info->mod = (void *)info->hdr + info->sechdrs[info->index.mod].sh_offset;
3053 * If we didn't load the .modinfo 'name' field earlier, fall back to
3054 * on-disk struct mod 'name' field.
3057 info->name = info->mod->name;
3059 if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
3060 info->index.vers = 0; /* Pretend no __versions section! */
3062 info->index.vers = find_sec(info, "__versions");
3064 info->index.pcpu = find_pcpusec(info);
3069 static int check_modinfo(struct module *mod, struct load_info *info, int flags)
3071 const char *modmagic = get_modinfo(info, "vermagic");
3074 if (flags & MODULE_INIT_IGNORE_VERMAGIC)
3077 /* This is allowed: modprobe --force will invalidate it. */
3079 err = try_to_force_load(mod, "bad vermagic");
3082 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
3083 pr_err("%s: version magic '%s' should be '%s'\n",
3084 info->name, modmagic, vermagic);
3088 if (!get_modinfo(info, "intree")) {
3089 if (!test_taint(TAINT_OOT_MODULE))
3090 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3092 add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
3095 check_modinfo_retpoline(mod, info);
3097 if (get_modinfo(info, "staging")) {
3098 add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
3099 pr_warn("%s: module is from the staging directory, the quality "
3100 "is unknown, you have been warned.\n", mod->name);
3103 err = check_modinfo_livepatch(mod, info);
3107 /* Set up license info based on the info section */
3108 set_license(mod, get_modinfo(info, "license"));
3113 static int find_module_sections(struct module *mod, struct load_info *info)
3115 mod->kp = section_objs(info, "__param",
3116 sizeof(*mod->kp), &mod->num_kp);
3117 mod->syms = section_objs(info, "__ksymtab",
3118 sizeof(*mod->syms), &mod->num_syms);
3119 mod->crcs = section_addr(info, "__kcrctab");
3120 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
3121 sizeof(*mod->gpl_syms),
3122 &mod->num_gpl_syms);
3123 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
3124 mod->gpl_future_syms = section_objs(info,
3125 "__ksymtab_gpl_future",
3126 sizeof(*mod->gpl_future_syms),
3127 &mod->num_gpl_future_syms);
3128 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
3130 #ifdef CONFIG_UNUSED_SYMBOLS
3131 mod->unused_syms = section_objs(info, "__ksymtab_unused",
3132 sizeof(*mod->unused_syms),
3133 &mod->num_unused_syms);
3134 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
3135 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
3136 sizeof(*mod->unused_gpl_syms),
3137 &mod->num_unused_gpl_syms);
3138 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
3140 #ifdef CONFIG_CONSTRUCTORS
3141 mod->ctors = section_objs(info, ".ctors",
3142 sizeof(*mod->ctors), &mod->num_ctors);
3144 mod->ctors = section_objs(info, ".init_array",
3145 sizeof(*mod->ctors), &mod->num_ctors);
3146 else if (find_sec(info, ".init_array")) {
3148 * This shouldn't happen with same compiler and binutils
3149 * building all parts of the module.
3151 pr_warn("%s: has both .ctors and .init_array.\n",
3157 mod->noinstr_text_start = section_objs(info, ".noinstr.text", 1,
3158 &mod->noinstr_text_size);
3160 #ifdef CONFIG_TRACEPOINTS
3161 mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
3162 sizeof(*mod->tracepoints_ptrs),
3163 &mod->num_tracepoints);
3165 #ifdef CONFIG_TREE_SRCU
3166 mod->srcu_struct_ptrs = section_objs(info, "___srcu_struct_ptrs",
3167 sizeof(*mod->srcu_struct_ptrs),
3168 &mod->num_srcu_structs);
3170 #ifdef CONFIG_BPF_EVENTS
3171 mod->bpf_raw_events = section_objs(info, "__bpf_raw_tp_map",
3172 sizeof(*mod->bpf_raw_events),
3173 &mod->num_bpf_raw_events);
3175 #ifdef CONFIG_JUMP_LABEL
3176 mod->jump_entries = section_objs(info, "__jump_table",
3177 sizeof(*mod->jump_entries),
3178 &mod->num_jump_entries);
3180 #ifdef CONFIG_EVENT_TRACING
3181 mod->trace_events = section_objs(info, "_ftrace_events",
3182 sizeof(*mod->trace_events),
3183 &mod->num_trace_events);
3184 mod->trace_evals = section_objs(info, "_ftrace_eval_map",
3185 sizeof(*mod->trace_evals),
3186 &mod->num_trace_evals);
3188 #ifdef CONFIG_TRACING
3189 mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
3190 sizeof(*mod->trace_bprintk_fmt_start),
3191 &mod->num_trace_bprintk_fmt);
3193 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3194 /* sechdrs[0].sh_size is always zero */
3195 mod->ftrace_callsites = section_objs(info, FTRACE_CALLSITE_SECTION,
3196 sizeof(*mod->ftrace_callsites),
3197 &mod->num_ftrace_callsites);
3199 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
3200 mod->ei_funcs = section_objs(info, "_error_injection_whitelist",
3201 sizeof(*mod->ei_funcs),
3202 &mod->num_ei_funcs);
3204 #ifdef CONFIG_KPROBES
3205 mod->kprobes_text_start = section_objs(info, ".kprobes.text", 1,
3206 &mod->kprobes_text_size);
3207 mod->kprobe_blacklist = section_objs(info, "_kprobe_blacklist",
3208 sizeof(unsigned long),
3209 &mod->num_kprobe_blacklist);
3211 mod->extable = section_objs(info, "__ex_table",
3212 sizeof(*mod->extable), &mod->num_exentries);
3214 if (section_addr(info, "__obsparm"))
3215 pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
3217 info->debug = section_objs(info, "__verbose",
3218 sizeof(*info->debug), &info->num_debug);
3223 static int move_module(struct module *mod, struct load_info *info)
3228 /* Do the allocs. */
3229 ptr = module_alloc(mod->core_layout.size);
3231 * The pointer to this block is stored in the module structure
3232 * which is inside the block. Just mark it as not being a
3235 kmemleak_not_leak(ptr);
3239 memset(ptr, 0, mod->core_layout.size);
3240 mod->core_layout.base = ptr;
3242 if (mod->init_layout.size) {
3243 ptr = module_alloc(mod->init_layout.size);
3245 * The pointer to this block is stored in the module structure
3246 * which is inside the block. This block doesn't need to be
3247 * scanned as it contains data and code that will be freed
3248 * after the module is initialized.
3250 kmemleak_ignore(ptr);
3252 module_memfree(mod->core_layout.base);
3255 memset(ptr, 0, mod->init_layout.size);
3256 mod->init_layout.base = ptr;
3258 mod->init_layout.base = NULL;
3260 /* Transfer each section which specifies SHF_ALLOC */
3261 pr_debug("final section addresses:\n");
3262 for (i = 0; i < info->hdr->e_shnum; i++) {
3264 Elf_Shdr *shdr = &info->sechdrs[i];
3266 if (!(shdr->sh_flags & SHF_ALLOC))
3269 if (shdr->sh_entsize & INIT_OFFSET_MASK)
3270 dest = mod->init_layout.base
3271 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
3273 dest = mod->core_layout.base + shdr->sh_entsize;
3275 if (shdr->sh_type != SHT_NOBITS)
3276 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
3277 /* Update sh_addr to point to copy in image. */
3278 shdr->sh_addr = (unsigned long)dest;
3279 pr_debug("\t0x%lx %s\n",
3280 (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
3286 static int check_module_license_and_versions(struct module *mod)
3288 int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE);
3291 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3292 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3293 * using GPL-only symbols it needs.
3295 if (strcmp(mod->name, "ndiswrapper") == 0)
3296 add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
3298 /* driverloader was caught wrongly pretending to be under GPL */
3299 if (strcmp(mod->name, "driverloader") == 0)
3300 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
3301 LOCKDEP_NOW_UNRELIABLE);
3303 /* lve claims to be GPL but upstream won't provide source */
3304 if (strcmp(mod->name, "lve") == 0)
3305 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
3306 LOCKDEP_NOW_UNRELIABLE);
3308 if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE))
3309 pr_warn("%s: module license taints kernel.\n", mod->name);
3311 #ifdef CONFIG_MODVERSIONS
3312 if ((mod->num_syms && !mod->crcs)
3313 || (mod->num_gpl_syms && !mod->gpl_crcs)
3314 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
3315 #ifdef CONFIG_UNUSED_SYMBOLS
3316 || (mod->num_unused_syms && !mod->unused_crcs)
3317 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
3320 return try_to_force_load(mod,
3321 "no versions for exported symbols");
3327 static void flush_module_icache(const struct module *mod)
3329 mm_segment_t old_fs;
3331 /* flush the icache in correct context */
3336 * Flush the instruction cache, since we've played with text.
3337 * Do it before processing of module parameters, so the module
3338 * can provide parameter accessor functions of its own.
3340 if (mod->init_layout.base)
3341 flush_icache_range((unsigned long)mod->init_layout.base,
3342 (unsigned long)mod->init_layout.base
3343 + mod->init_layout.size);
3344 flush_icache_range((unsigned long)mod->core_layout.base,
3345 (unsigned long)mod->core_layout.base + mod->core_layout.size);
3350 int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
3358 /* module_blacklist is a comma-separated list of module names */
3359 static char *module_blacklist;
3360 static bool blacklisted(const char *module_name)
3365 if (!module_blacklist)
3368 for (p = module_blacklist; *p; p += len) {
3369 len = strcspn(p, ",");
3370 if (strlen(module_name) == len && !memcmp(module_name, p, len))
3377 core_param(module_blacklist, module_blacklist, charp, 0400);
3379 static struct module *layout_and_allocate(struct load_info *info, int flags)
3385 err = check_modinfo(info->mod, info, flags);
3387 return ERR_PTR(err);
3389 /* Allow arches to frob section contents and sizes. */
3390 err = module_frob_arch_sections(info->hdr, info->sechdrs,
3391 info->secstrings, info->mod);
3393 return ERR_PTR(err);
3395 /* We will do a special allocation for per-cpu sections later. */
3396 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
3399 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3400 * layout_sections() can put it in the right place.
3401 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3403 ndx = find_sec(info, ".data..ro_after_init");
3405 info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT;
3407 * Mark the __jump_table section as ro_after_init as well: these data
3408 * structures are never modified, with the exception of entries that
3409 * refer to code in the __init section, which are annotated as such
3410 * at module load time.
3412 ndx = find_sec(info, "__jump_table");
3414 info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT;
3416 /* Determine total sizes, and put offsets in sh_entsize. For now
3417 this is done generically; there doesn't appear to be any
3418 special cases for the architectures. */
3419 layout_sections(info->mod, info);
3420 layout_symtab(info->mod, info);
3422 /* Allocate and move to the final place */
3423 err = move_module(info->mod, info);
3425 return ERR_PTR(err);
3427 /* Module has been copied to its final place now: return it. */
3428 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
3429 kmemleak_load_module(mod, info);
3433 /* mod is no longer valid after this! */
3434 static void module_deallocate(struct module *mod, struct load_info *info)
3436 percpu_modfree(mod);
3437 module_arch_freeing_init(mod);
3438 module_memfree(mod->init_layout.base);
3439 module_memfree(mod->core_layout.base);
3442 int __weak module_finalize(const Elf_Ehdr *hdr,
3443 const Elf_Shdr *sechdrs,
3449 static int post_relocation(struct module *mod, const struct load_info *info)
3451 /* Sort exception table now relocations are done. */
3452 sort_extable(mod->extable, mod->extable + mod->num_exentries);
3454 /* Copy relocated percpu area over. */
3455 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
3456 info->sechdrs[info->index.pcpu].sh_size);
3458 /* Setup kallsyms-specific fields. */
3459 add_kallsyms(mod, info);
3461 /* Arch-specific module finalizing. */
3462 return module_finalize(info->hdr, info->sechdrs, mod);
3465 /* Is this module of this name done loading? No locks held. */
3466 static bool finished_loading(const char *name)
3472 * The module_mutex should not be a heavily contended lock;
3473 * if we get the occasional sleep here, we'll go an extra iteration
3474 * in the wait_event_interruptible(), which is harmless.
3476 sched_annotate_sleep();
3477 mutex_lock(&module_mutex);
3478 mod = find_module_all(name, strlen(name), true);
3479 ret = !mod || mod->state == MODULE_STATE_LIVE;
3480 mutex_unlock(&module_mutex);
3485 /* Call module constructors. */
3486 static void do_mod_ctors(struct module *mod)
3488 #ifdef CONFIG_CONSTRUCTORS
3491 for (i = 0; i < mod->num_ctors; i++)
3496 /* For freeing module_init on success, in case kallsyms traversing */
3497 struct mod_initfree {
3498 struct llist_node node;
3502 static void do_free_init(struct work_struct *w)
3504 struct llist_node *pos, *n, *list;
3505 struct mod_initfree *initfree;
3507 list = llist_del_all(&init_free_list);
3511 llist_for_each_safe(pos, n, list) {
3512 initfree = container_of(pos, struct mod_initfree, node);
3513 module_memfree(initfree->module_init);
3518 static int __init modules_wq_init(void)
3520 INIT_WORK(&init_free_wq, do_free_init);
3521 init_llist_head(&init_free_list);
3524 module_init(modules_wq_init);
3527 * This is where the real work happens.
3529 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3530 * helper command 'lx-symbols'.
3532 static noinline int do_init_module(struct module *mod)
3535 struct mod_initfree *freeinit;
3537 freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
3542 freeinit->module_init = mod->init_layout.base;
3545 * We want to find out whether @mod uses async during init. Clear
3546 * PF_USED_ASYNC. async_schedule*() will set it.
3548 current->flags &= ~PF_USED_ASYNC;
3551 /* Start the module */
3552 if (mod->init != NULL)
3553 ret = do_one_initcall(mod->init);
3555 goto fail_free_freeinit;
3558 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3559 "follow 0/-E convention\n"
3560 "%s: loading module anyway...\n",
3561 __func__, mod->name, ret, __func__);
3565 /* Now it's a first class citizen! */
3566 mod->state = MODULE_STATE_LIVE;
3567 blocking_notifier_call_chain(&module_notify_list,
3568 MODULE_STATE_LIVE, mod);
3571 * We need to finish all async code before the module init sequence
3572 * is done. This has potential to deadlock. For example, a newly
3573 * detected block device can trigger request_module() of the
3574 * default iosched from async probing task. Once userland helper
3575 * reaches here, async_synchronize_full() will wait on the async
3576 * task waiting on request_module() and deadlock.
3578 * This deadlock is avoided by perfomring async_synchronize_full()
3579 * iff module init queued any async jobs. This isn't a full
3580 * solution as it will deadlock the same if module loading from
3581 * async jobs nests more than once; however, due to the various
3582 * constraints, this hack seems to be the best option for now.
3583 * Please refer to the following thread for details.
3585 * http://thread.gmane.org/gmane.linux.kernel/1420814
3587 if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC))
3588 async_synchronize_full();
3590 ftrace_free_mem(mod, mod->init_layout.base, mod->init_layout.base +
3591 mod->init_layout.size);
3592 mutex_lock(&module_mutex);
3593 /* Drop initial reference. */
3595 trim_init_extable(mod);
3596 #ifdef CONFIG_KALLSYMS
3597 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3598 rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
3600 module_enable_ro(mod, true);
3601 mod_tree_remove_init(mod);
3602 module_arch_freeing_init(mod);
3603 mod->init_layout.base = NULL;
3604 mod->init_layout.size = 0;
3605 mod->init_layout.ro_size = 0;
3606 mod->init_layout.ro_after_init_size = 0;
3607 mod->init_layout.text_size = 0;
3609 * We want to free module_init, but be aware that kallsyms may be
3610 * walking this with preempt disabled. In all the failure paths, we
3611 * call synchronize_rcu(), but we don't want to slow down the success
3612 * path. module_memfree() cannot be called in an interrupt, so do the
3613 * work and call synchronize_rcu() in a work queue.
3615 * Note that module_alloc() on most architectures creates W+X page
3616 * mappings which won't be cleaned up until do_free_init() runs. Any
3617 * code such as mark_rodata_ro() which depends on those mappings to
3618 * be cleaned up needs to sync with the queued work - ie
3621 if (llist_add(&freeinit->node, &init_free_list))
3622 schedule_work(&init_free_wq);
3624 mutex_unlock(&module_mutex);
3625 wake_up_all(&module_wq);
3632 /* Try to protect us from buggy refcounters. */
3633 mod->state = MODULE_STATE_GOING;
3636 blocking_notifier_call_chain(&module_notify_list,
3637 MODULE_STATE_GOING, mod);
3638 klp_module_going(mod);
3639 ftrace_release_mod(mod);
3641 wake_up_all(&module_wq);
3645 static int may_init_module(void)
3647 if (!capable(CAP_SYS_MODULE) || modules_disabled)
3654 * We try to place it in the list now to make sure it's unique before
3655 * we dedicate too many resources. In particular, temporary percpu
3656 * memory exhaustion.
3658 static int add_unformed_module(struct module *mod)
3663 mod->state = MODULE_STATE_UNFORMED;
3666 mutex_lock(&module_mutex);
3667 old = find_module_all(mod->name, strlen(mod->name), true);
3669 if (old->state != MODULE_STATE_LIVE) {
3670 /* Wait in case it fails to load. */
3671 mutex_unlock(&module_mutex);
3672 err = wait_event_interruptible(module_wq,
3673 finished_loading(mod->name));
3681 mod_update_bounds(mod);
3682 list_add_rcu(&mod->list, &modules);
3683 mod_tree_insert(mod);
3687 mutex_unlock(&module_mutex);
3692 static int complete_formation(struct module *mod, struct load_info *info)
3696 mutex_lock(&module_mutex);
3698 /* Find duplicate symbols (must be called under lock). */
3699 err = verify_exported_symbols(mod);
3703 /* This relies on module_mutex for list integrity. */
3704 module_bug_finalize(info->hdr, info->sechdrs, mod);
3706 module_enable_ro(mod, false);
3707 module_enable_nx(mod);
3708 module_enable_x(mod);
3710 /* Mark state as coming so strong_try_module_get() ignores us,
3711 * but kallsyms etc. can see us. */
3712 mod->state = MODULE_STATE_COMING;
3713 mutex_unlock(&module_mutex);
3718 mutex_unlock(&module_mutex);
3722 static int prepare_coming_module(struct module *mod)
3726 ftrace_module_enable(mod);
3727 err = klp_module_coming(mod);
3731 blocking_notifier_call_chain(&module_notify_list,
3732 MODULE_STATE_COMING, mod);
3736 static int unknown_module_param_cb(char *param, char *val, const char *modname,
3739 struct module *mod = arg;
3742 if (strcmp(param, "async_probe") == 0) {
3743 mod->async_probe_requested = true;
3747 /* Check for magic 'dyndbg' arg */
3748 ret = ddebug_dyndbg_module_param_cb(param, val, modname);
3750 pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
3754 /* Allocate and load the module: note that size of section 0 is always
3755 zero, and we rely on this for optional sections. */
3756 static int load_module(struct load_info *info, const char __user *uargs,
3763 err = elf_header_check(info);
3767 err = setup_load_info(info, flags);
3771 if (blacklisted(info->name)) {
3776 err = module_sig_check(info, flags);
3780 err = rewrite_section_headers(info, flags);
3784 /* Check module struct version now, before we try to use module. */
3785 if (!check_modstruct_version(info, info->mod)) {
3790 /* Figure out module layout, and allocate all the memory. */
3791 mod = layout_and_allocate(info, flags);
3797 audit_log_kern_module(mod->name);
3799 /* Reserve our place in the list. */
3800 err = add_unformed_module(mod);
3804 #ifdef CONFIG_MODULE_SIG
3805 mod->sig_ok = info->sig_ok;
3807 pr_notice_once("%s: module verification failed: signature "
3808 "and/or required key missing - tainting "
3809 "kernel\n", mod->name);
3810 add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
3814 /* To avoid stressing percpu allocator, do this once we're unique. */
3815 err = percpu_modalloc(mod, info);
3819 /* Now module is in final location, initialize linked lists, etc. */
3820 err = module_unload_init(mod);
3824 init_param_lock(mod);
3826 /* Now we've got everything in the final locations, we can
3827 * find optional sections. */
3828 err = find_module_sections(mod, info);
3832 err = check_module_license_and_versions(mod);
3836 /* Set up MODINFO_ATTR fields */
3837 setup_modinfo(mod, info);
3839 /* Fix up syms, so that st_value is a pointer to location. */
3840 err = simplify_symbols(mod, info);
3844 err = apply_relocations(mod, info);
3848 err = post_relocation(mod, info);
3852 flush_module_icache(mod);
3854 /* Now copy in args */
3855 mod->args = strndup_user(uargs, ~0UL >> 1);
3856 if (IS_ERR(mod->args)) {
3857 err = PTR_ERR(mod->args);
3858 goto free_arch_cleanup;
3861 dynamic_debug_setup(mod, info->debug, info->num_debug);
3863 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3864 ftrace_module_init(mod);
3866 /* Finally it's fully formed, ready to start executing. */
3867 err = complete_formation(mod, info);
3869 goto ddebug_cleanup;
3871 err = prepare_coming_module(mod);
3875 /* Module is ready to execute: parsing args may do that. */
3876 after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
3878 unknown_module_param_cb);
3879 if (IS_ERR(after_dashes)) {
3880 err = PTR_ERR(after_dashes);
3881 goto coming_cleanup;
3882 } else if (after_dashes) {
3883 pr_warn("%s: parameters '%s' after `--' ignored\n",
3884 mod->name, after_dashes);
3887 /* Link in to sysfs. */
3888 err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3890 goto coming_cleanup;
3892 if (is_livepatch_module(mod)) {
3893 err = copy_module_elf(mod, info);
3898 /* Get rid of temporary copy. */
3902 trace_module_load(mod);
3904 return do_init_module(mod);
3907 mod_sysfs_teardown(mod);
3909 mod->state = MODULE_STATE_GOING;
3910 destroy_params(mod->kp, mod->num_kp);
3911 blocking_notifier_call_chain(&module_notify_list,
3912 MODULE_STATE_GOING, mod);
3913 klp_module_going(mod);
3915 /* module_bug_cleanup needs module_mutex protection */
3916 mutex_lock(&module_mutex);
3917 module_bug_cleanup(mod);
3918 mutex_unlock(&module_mutex);
3921 ftrace_release_mod(mod);
3922 dynamic_debug_remove(mod, info->debug);
3926 module_arch_cleanup(mod);
3930 module_unload_free(mod);
3932 mutex_lock(&module_mutex);
3933 /* Unlink carefully: kallsyms could be walking list. */
3934 list_del_rcu(&mod->list);
3935 mod_tree_remove(mod);
3936 wake_up_all(&module_wq);
3937 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3939 mutex_unlock(&module_mutex);
3941 /* Free lock-classes; relies on the preceding sync_rcu() */
3942 lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
3944 module_deallocate(mod, info);
3950 SYSCALL_DEFINE3(init_module, void __user *, umod,
3951 unsigned long, len, const char __user *, uargs)
3954 struct load_info info = { };
3956 err = may_init_module();
3960 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3963 err = copy_module_from_user(umod, len, &info);
3967 return load_module(&info, uargs, 0);
3970 SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3972 struct load_info info = { };
3977 err = may_init_module();
3981 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3983 if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3984 |MODULE_INIT_IGNORE_VERMAGIC))
3987 err = kernel_read_file_from_fd(fd, &hdr, &size, INT_MAX,
3994 return load_module(&info, uargs, flags);
3997 static inline int within(unsigned long addr, void *start, unsigned long size)
3999 return ((void *)addr >= start && (void *)addr < start + size);
4002 #ifdef CONFIG_KALLSYMS
4004 * This ignores the intensely annoying "mapping symbols" found
4005 * in ARM ELF files: $a, $t and $d.
4007 static inline int is_arm_mapping_symbol(const char *str)
4009 if (str[0] == '.' && str[1] == 'L')
4011 return str[0] == '$' && strchr("axtd", str[1])
4012 && (str[2] == '\0' || str[2] == '.');
4015 static const char *kallsyms_symbol_name(struct mod_kallsyms *kallsyms, unsigned int symnum)
4017 return kallsyms->strtab + kallsyms->symtab[symnum].st_name;
4021 * Given a module and address, find the corresponding symbol and return its name
4022 * while providing its size and offset if needed.
4024 static const char *find_kallsyms_symbol(struct module *mod,
4026 unsigned long *size,
4027 unsigned long *offset)
4029 unsigned int i, best = 0;
4030 unsigned long nextval, bestval;
4031 struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
4033 /* At worse, next value is at end of module */
4034 if (within_module_init(addr, mod))
4035 nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size;
4037 nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size;
4039 bestval = kallsyms_symbol_value(&kallsyms->symtab[best]);
4041 /* Scan for closest preceding symbol, and next symbol. (ELF
4042 starts real symbols at 1). */
4043 for (i = 1; i < kallsyms->num_symtab; i++) {
4044 const Elf_Sym *sym = &kallsyms->symtab[i];
4045 unsigned long thisval = kallsyms_symbol_value(sym);
4047 if (sym->st_shndx == SHN_UNDEF)
4050 /* We ignore unnamed symbols: they're uninformative
4051 * and inserted at a whim. */
4052 if (*kallsyms_symbol_name(kallsyms, i) == '\0'
4053 || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms, i)))
4056 if (thisval <= addr && thisval > bestval) {
4060 if (thisval > addr && thisval < nextval)
4068 *size = nextval - bestval;
4070 *offset = addr - bestval;
4072 return kallsyms_symbol_name(kallsyms, best);
4075 void * __weak dereference_module_function_descriptor(struct module *mod,
4081 /* For kallsyms to ask for address resolution. NULL means not found. Careful
4082 * not to lock to avoid deadlock on oopses, simply disable preemption. */
4083 const char *module_address_lookup(unsigned long addr,
4084 unsigned long *size,
4085 unsigned long *offset,
4089 const char *ret = NULL;
4093 mod = __module_address(addr);
4096 *modname = mod->name;
4098 ret = find_kallsyms_symbol(mod, addr, size, offset);
4100 /* Make a copy in here where it's safe */
4102 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
4110 int lookup_module_symbol_name(unsigned long addr, char *symname)
4115 list_for_each_entry_rcu(mod, &modules, list) {
4116 if (mod->state == MODULE_STATE_UNFORMED)
4118 if (within_module(addr, mod)) {
4121 sym = find_kallsyms_symbol(mod, addr, NULL, NULL);
4125 strlcpy(symname, sym, KSYM_NAME_LEN);
4135 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
4136 unsigned long *offset, char *modname, char *name)
4141 list_for_each_entry_rcu(mod, &modules, list) {
4142 if (mod->state == MODULE_STATE_UNFORMED)
4144 if (within_module(addr, mod)) {
4147 sym = find_kallsyms_symbol(mod, addr, size, offset);
4151 strlcpy(modname, mod->name, MODULE_NAME_LEN);
4153 strlcpy(name, sym, KSYM_NAME_LEN);
4163 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
4164 char *name, char *module_name, int *exported)
4169 list_for_each_entry_rcu(mod, &modules, list) {
4170 struct mod_kallsyms *kallsyms;
4172 if (mod->state == MODULE_STATE_UNFORMED)
4174 kallsyms = rcu_dereference_sched(mod->kallsyms);
4175 if (symnum < kallsyms->num_symtab) {
4176 const Elf_Sym *sym = &kallsyms->symtab[symnum];
4178 *value = kallsyms_symbol_value(sym);
4179 *type = kallsyms->typetab[symnum];
4180 strlcpy(name, kallsyms_symbol_name(kallsyms, symnum), KSYM_NAME_LEN);
4181 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
4182 *exported = is_exported(name, *value, mod);
4186 symnum -= kallsyms->num_symtab;
4192 /* Given a module and name of symbol, find and return the symbol's value */
4193 static unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name)
4196 struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
4198 for (i = 0; i < kallsyms->num_symtab; i++) {
4199 const Elf_Sym *sym = &kallsyms->symtab[i];
4201 if (strcmp(name, kallsyms_symbol_name(kallsyms, i)) == 0 &&
4202 sym->st_shndx != SHN_UNDEF)
4203 return kallsyms_symbol_value(sym);
4208 /* Look for this name: can be of form module:name. */
4209 unsigned long module_kallsyms_lookup_name(const char *name)
4213 unsigned long ret = 0;
4215 /* Don't lock: we're in enough trouble already. */
4217 if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) {
4218 if ((mod = find_module_all(name, colon - name, false)) != NULL)
4219 ret = find_kallsyms_symbol_value(mod, colon+1);
4221 list_for_each_entry_rcu(mod, &modules, list) {
4222 if (mod->state == MODULE_STATE_UNFORMED)
4224 if ((ret = find_kallsyms_symbol_value(mod, name)) != 0)
4232 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
4233 struct module *, unsigned long),
4240 module_assert_mutex();
4242 list_for_each_entry(mod, &modules, list) {
4243 /* We hold module_mutex: no need for rcu_dereference_sched */
4244 struct mod_kallsyms *kallsyms = mod->kallsyms;
4246 if (mod->state == MODULE_STATE_UNFORMED)
4248 for (i = 0; i < kallsyms->num_symtab; i++) {
4249 const Elf_Sym *sym = &kallsyms->symtab[i];
4251 if (sym->st_shndx == SHN_UNDEF)
4254 ret = fn(data, kallsyms_symbol_name(kallsyms, i),
4255 mod, kallsyms_symbol_value(sym));
4262 #endif /* CONFIG_KALLSYMS */
4264 /* Maximum number of characters written by module_flags() */
4265 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4267 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4268 static char *module_flags(struct module *mod, char *buf)
4272 BUG_ON(mod->state == MODULE_STATE_UNFORMED);
4274 mod->state == MODULE_STATE_GOING ||
4275 mod->state == MODULE_STATE_COMING) {
4277 bx += module_flags_taint(mod, buf + bx);
4278 /* Show a - for module-is-being-unloaded */
4279 if (mod->state == MODULE_STATE_GOING)
4281 /* Show a + for module-is-being-loaded */
4282 if (mod->state == MODULE_STATE_COMING)
4291 #ifdef CONFIG_PROC_FS
4292 /* Called by the /proc file system to return a list of modules. */
4293 static void *m_start(struct seq_file *m, loff_t *pos)
4295 mutex_lock(&module_mutex);
4296 return seq_list_start(&modules, *pos);
4299 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
4301 return seq_list_next(p, &modules, pos);
4304 static void m_stop(struct seq_file *m, void *p)
4306 mutex_unlock(&module_mutex);
4309 static int m_show(struct seq_file *m, void *p)
4311 struct module *mod = list_entry(p, struct module, list);
4312 char buf[MODULE_FLAGS_BUF_SIZE];
4315 /* We always ignore unformed modules. */
4316 if (mod->state == MODULE_STATE_UNFORMED)
4319 seq_printf(m, "%s %u",
4320 mod->name, mod->init_layout.size + mod->core_layout.size);
4321 print_unload_info(m, mod);
4323 /* Informative for users. */
4324 seq_printf(m, " %s",
4325 mod->state == MODULE_STATE_GOING ? "Unloading" :
4326 mod->state == MODULE_STATE_COMING ? "Loading" :
4328 /* Used by oprofile and other similar tools. */
4329 value = m->private ? NULL : mod->core_layout.base;
4330 seq_printf(m, " 0x%px", value);
4334 seq_printf(m, " %s", module_flags(mod, buf));
4340 /* Format: modulename size refcount deps address
4342 Where refcount is a number or -, and deps is a comma-separated list
4345 static const struct seq_operations modules_op = {
4353 * This also sets the "private" pointer to non-NULL if the
4354 * kernel pointers should be hidden (so you can just test
4355 * "m->private" to see if you should keep the values private).
4357 * We use the same logic as for /proc/kallsyms.
4359 static int modules_open(struct inode *inode, struct file *file)
4361 int err = seq_open(file, &modules_op);
4364 struct seq_file *m = file->private_data;
4365 m->private = kallsyms_show_value() ? NULL : (void *)8ul;
4371 static const struct proc_ops modules_proc_ops = {
4372 .proc_flags = PROC_ENTRY_PERMANENT,
4373 .proc_open = modules_open,
4374 .proc_read = seq_read,
4375 .proc_lseek = seq_lseek,
4376 .proc_release = seq_release,
4379 static int __init proc_modules_init(void)
4381 proc_create("modules", 0, NULL, &modules_proc_ops);
4384 module_init(proc_modules_init);
4387 /* Given an address, look for it in the module exception tables. */
4388 const struct exception_table_entry *search_module_extables(unsigned long addr)
4390 const struct exception_table_entry *e = NULL;
4394 mod = __module_address(addr);
4398 if (!mod->num_exentries)
4401 e = search_extable(mod->extable,
4408 * Now, if we found one, we are running inside it now, hence
4409 * we cannot unload the module, hence no refcnt needed.
4415 * is_module_address - is this address inside a module?
4416 * @addr: the address to check.
4418 * See is_module_text_address() if you simply want to see if the address
4419 * is code (not data).
4421 bool is_module_address(unsigned long addr)
4426 ret = __module_address(addr) != NULL;
4433 * __module_address - get the module which contains an address.
4434 * @addr: the address.
4436 * Must be called with preempt disabled or module mutex held so that
4437 * module doesn't get freed during this.
4439 struct module *__module_address(unsigned long addr)
4443 if (addr < module_addr_min || addr > module_addr_max)
4446 module_assert_mutex_or_preempt();
4448 mod = mod_find(addr);
4450 BUG_ON(!within_module(addr, mod));
4451 if (mod->state == MODULE_STATE_UNFORMED)
4456 EXPORT_SYMBOL_GPL(__module_address);
4459 * is_module_text_address - is this address inside module code?
4460 * @addr: the address to check.
4462 * See is_module_address() if you simply want to see if the address is
4463 * anywhere in a module. See kernel_text_address() for testing if an
4464 * address corresponds to kernel or module code.
4466 bool is_module_text_address(unsigned long addr)
4471 ret = __module_text_address(addr) != NULL;
4478 * __module_text_address - get the module whose code contains an address.
4479 * @addr: the address.
4481 * Must be called with preempt disabled or module mutex held so that
4482 * module doesn't get freed during this.
4484 struct module *__module_text_address(unsigned long addr)
4486 struct module *mod = __module_address(addr);
4488 /* Make sure it's within the text section. */
4489 if (!within(addr, mod->init_layout.base, mod->init_layout.text_size)
4490 && !within(addr, mod->core_layout.base, mod->core_layout.text_size))
4495 EXPORT_SYMBOL_GPL(__module_text_address);
4497 /* Don't grab lock, we're oopsing. */
4498 void print_modules(void)
4501 char buf[MODULE_FLAGS_BUF_SIZE];
4503 printk(KERN_DEFAULT "Modules linked in:");
4504 /* Most callers should already have preempt disabled, but make sure */
4506 list_for_each_entry_rcu(mod, &modules, list) {
4507 if (mod->state == MODULE_STATE_UNFORMED)
4509 pr_cont(" %s%s", mod->name, module_flags(mod, buf));
4512 if (last_unloaded_module[0])
4513 pr_cont(" [last unloaded: %s]", last_unloaded_module);
4517 #ifdef CONFIG_MODVERSIONS
4518 /* Generate the signature for all relevant module structures here.
4519 * If these change, we don't want to try to parse the module. */
4520 void module_layout(struct module *mod,
4521 struct modversion_info *ver,
4522 struct kernel_param *kp,
4523 struct kernel_symbol *ks,
4524 struct tracepoint * const *tp)
4527 EXPORT_SYMBOL(module_layout);