2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 #include <linux/export.h>
20 #include <linux/moduleloader.h>
21 #include <linux/trace_events.h>
22 #include <linux/init.h>
23 #include <linux/kallsyms.h>
24 #include <linux/file.h>
26 #include <linux/sysfs.h>
27 #include <linux/kernel.h>
28 #include <linux/slab.h>
29 #include <linux/vmalloc.h>
30 #include <linux/elf.h>
31 #include <linux/proc_fs.h>
32 #include <linux/security.h>
33 #include <linux/seq_file.h>
34 #include <linux/syscalls.h>
35 #include <linux/fcntl.h>
36 #include <linux/rcupdate.h>
37 #include <linux/capability.h>
38 #include <linux/cpu.h>
39 #include <linux/moduleparam.h>
40 #include <linux/errno.h>
41 #include <linux/err.h>
42 #include <linux/vermagic.h>
43 #include <linux/notifier.h>
44 #include <linux/sched.h>
45 #include <linux/device.h>
46 #include <linux/string.h>
47 #include <linux/mutex.h>
48 #include <linux/rculist.h>
49 #include <asm/uaccess.h>
50 #include <asm/cacheflush.h>
51 #include <asm/mmu_context.h>
52 #include <linux/license.h>
53 #include <asm/sections.h>
54 #include <linux/tracepoint.h>
55 #include <linux/ftrace.h>
56 #include <linux/async.h>
57 #include <linux/percpu.h>
58 #include <linux/kmemleak.h>
59 #include <linux/jump_label.h>
60 #include <linux/pfn.h>
61 #include <linux/bsearch.h>
62 #include <uapi/linux/module.h>
63 #include "module-internal.h"
65 #define CREATE_TRACE_POINTS
66 #include <trace/events/module.h>
68 #ifndef ARCH_SHF_SMALL
69 #define ARCH_SHF_SMALL 0
73 * Modules' sections will be aligned on page boundaries
74 * to ensure complete separation of code and data, but
75 * only when CONFIG_DEBUG_SET_MODULE_RONX=y
77 #ifdef CONFIG_DEBUG_SET_MODULE_RONX
78 # define debug_align(X) ALIGN(X, PAGE_SIZE)
80 # define debug_align(X) (X)
83 /* If this is set, the section belongs in the init part of the module */
84 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
88 * 1) List of modules (also safely readable with preempt_disable),
89 * 2) module_use links,
90 * 3) module_addr_min/module_addr_max.
91 * (delete and add uses RCU list operations). */
92 DEFINE_MUTEX(module_mutex);
93 EXPORT_SYMBOL_GPL(module_mutex);
94 static LIST_HEAD(modules);
96 #ifdef CONFIG_MODULES_TREE_LOOKUP
99 * Use a latched RB-tree for __module_address(); this allows us to use
100 * RCU-sched lookups of the address from any context.
102 * This is conditional on PERF_EVENTS || TRACING because those can really hit
103 * __module_address() hard by doing a lot of stack unwinding; potentially from
107 static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
109 struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
111 return (unsigned long)layout->base;
114 static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
116 struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
118 return (unsigned long)layout->size;
121 static __always_inline bool
122 mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b)
124 return __mod_tree_val(a) < __mod_tree_val(b);
127 static __always_inline int
128 mod_tree_comp(void *key, struct latch_tree_node *n)
130 unsigned long val = (unsigned long)key;
131 unsigned long start, end;
133 start = __mod_tree_val(n);
137 end = start + __mod_tree_size(n);
144 static const struct latch_tree_ops mod_tree_ops = {
145 .less = mod_tree_less,
146 .comp = mod_tree_comp,
149 static struct mod_tree_root {
150 struct latch_tree_root root;
151 unsigned long addr_min;
152 unsigned long addr_max;
153 } mod_tree __cacheline_aligned = {
157 #define module_addr_min mod_tree.addr_min
158 #define module_addr_max mod_tree.addr_max
160 static noinline void __mod_tree_insert(struct mod_tree_node *node)
162 latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops);
165 static void __mod_tree_remove(struct mod_tree_node *node)
167 latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops);
171 * These modifications: insert, remove_init and remove; are serialized by the
174 static void mod_tree_insert(struct module *mod)
176 mod->core_layout.mtn.mod = mod;
177 mod->init_layout.mtn.mod = mod;
179 __mod_tree_insert(&mod->core_layout.mtn);
180 if (mod->init_layout.size)
181 __mod_tree_insert(&mod->init_layout.mtn);
184 static void mod_tree_remove_init(struct module *mod)
186 if (mod->init_layout.size)
187 __mod_tree_remove(&mod->init_layout.mtn);
190 static void mod_tree_remove(struct module *mod)
192 __mod_tree_remove(&mod->core_layout.mtn);
193 mod_tree_remove_init(mod);
196 static struct module *mod_find(unsigned long addr)
198 struct latch_tree_node *ltn;
200 ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops);
204 return container_of(ltn, struct mod_tree_node, node)->mod;
207 #else /* MODULES_TREE_LOOKUP */
209 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
211 static void mod_tree_insert(struct module *mod) { }
212 static void mod_tree_remove_init(struct module *mod) { }
213 static void mod_tree_remove(struct module *mod) { }
215 static struct module *mod_find(unsigned long addr)
219 list_for_each_entry_rcu(mod, &modules, list) {
220 if (within_module(addr, mod))
227 #endif /* MODULES_TREE_LOOKUP */
230 * Bounds of module text, for speeding up __module_address.
231 * Protected by module_mutex.
233 static void __mod_update_bounds(void *base, unsigned int size)
235 unsigned long min = (unsigned long)base;
236 unsigned long max = min + size;
238 if (min < module_addr_min)
239 module_addr_min = min;
240 if (max > module_addr_max)
241 module_addr_max = max;
244 static void mod_update_bounds(struct module *mod)
246 __mod_update_bounds(mod->core_layout.base, mod->core_layout.size);
247 if (mod->init_layout.size)
248 __mod_update_bounds(mod->init_layout.base, mod->init_layout.size);
251 #ifdef CONFIG_KGDB_KDB
252 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
253 #endif /* CONFIG_KGDB_KDB */
255 static void module_assert_mutex(void)
257 lockdep_assert_held(&module_mutex);
260 static void module_assert_mutex_or_preempt(void)
262 #ifdef CONFIG_LOCKDEP
263 if (unlikely(!debug_locks))
266 WARN_ON(!rcu_read_lock_sched_held() &&
267 !lockdep_is_held(&module_mutex));
271 static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE);
272 #ifndef CONFIG_MODULE_SIG_FORCE
273 module_param(sig_enforce, bool_enable_only, 0644);
274 #endif /* !CONFIG_MODULE_SIG_FORCE */
276 /* Block module loading/unloading? */
277 int modules_disabled = 0;
278 core_param(nomodule, modules_disabled, bint, 0);
280 /* Waiting for a module to finish initializing? */
281 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
283 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
285 int register_module_notifier(struct notifier_block *nb)
287 return blocking_notifier_chain_register(&module_notify_list, nb);
289 EXPORT_SYMBOL(register_module_notifier);
291 int unregister_module_notifier(struct notifier_block *nb)
293 return blocking_notifier_chain_unregister(&module_notify_list, nb);
295 EXPORT_SYMBOL(unregister_module_notifier);
301 char *secstrings, *strtab;
302 unsigned long symoffs, stroffs;
303 struct _ddebug *debug;
304 unsigned int num_debug;
307 unsigned int sym, str, mod, vers, info, pcpu;
311 /* We require a truly strong try_module_get(): 0 means failure due to
312 ongoing or failed initialization etc. */
313 static inline int strong_try_module_get(struct module *mod)
315 BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
316 if (mod && mod->state == MODULE_STATE_COMING)
318 if (try_module_get(mod))
324 static inline void add_taint_module(struct module *mod, unsigned flag,
325 enum lockdep_ok lockdep_ok)
327 add_taint(flag, lockdep_ok);
328 mod->taints |= (1U << flag);
332 * A thread that wants to hold a reference to a module only while it
333 * is running can call this to safely exit. nfsd and lockd use this.
335 void __module_put_and_exit(struct module *mod, long code)
340 EXPORT_SYMBOL(__module_put_and_exit);
342 /* Find a module section: 0 means not found. */
343 static unsigned int find_sec(const struct load_info *info, const char *name)
347 for (i = 1; i < info->hdr->e_shnum; i++) {
348 Elf_Shdr *shdr = &info->sechdrs[i];
349 /* Alloc bit cleared means "ignore it." */
350 if ((shdr->sh_flags & SHF_ALLOC)
351 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
357 /* Find a module section, or NULL. */
358 static void *section_addr(const struct load_info *info, const char *name)
360 /* Section 0 has sh_addr 0. */
361 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
364 /* Find a module section, or NULL. Fill in number of "objects" in section. */
365 static void *section_objs(const struct load_info *info,
370 unsigned int sec = find_sec(info, name);
372 /* Section 0 has sh_addr 0 and sh_size 0. */
373 *num = info->sechdrs[sec].sh_size / object_size;
374 return (void *)info->sechdrs[sec].sh_addr;
377 /* Provided by the linker */
378 extern const struct kernel_symbol __start___ksymtab[];
379 extern const struct kernel_symbol __stop___ksymtab[];
380 extern const struct kernel_symbol __start___ksymtab_gpl[];
381 extern const struct kernel_symbol __stop___ksymtab_gpl[];
382 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
383 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
384 extern const unsigned long __start___kcrctab[];
385 extern const unsigned long __start___kcrctab_gpl[];
386 extern const unsigned long __start___kcrctab_gpl_future[];
387 #ifdef CONFIG_UNUSED_SYMBOLS
388 extern const struct kernel_symbol __start___ksymtab_unused[];
389 extern const struct kernel_symbol __stop___ksymtab_unused[];
390 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
391 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
392 extern const unsigned long __start___kcrctab_unused[];
393 extern const unsigned long __start___kcrctab_unused_gpl[];
396 #ifndef CONFIG_MODVERSIONS
397 #define symversion(base, idx) NULL
399 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
402 static bool each_symbol_in_section(const struct symsearch *arr,
403 unsigned int arrsize,
404 struct module *owner,
405 bool (*fn)(const struct symsearch *syms,
406 struct module *owner,
412 for (j = 0; j < arrsize; j++) {
413 if (fn(&arr[j], owner, data))
420 /* Returns true as soon as fn returns true, otherwise false. */
421 bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
422 struct module *owner,
427 static const struct symsearch arr[] = {
428 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
429 NOT_GPL_ONLY, false },
430 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
431 __start___kcrctab_gpl,
433 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
434 __start___kcrctab_gpl_future,
435 WILL_BE_GPL_ONLY, false },
436 #ifdef CONFIG_UNUSED_SYMBOLS
437 { __start___ksymtab_unused, __stop___ksymtab_unused,
438 __start___kcrctab_unused,
439 NOT_GPL_ONLY, true },
440 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
441 __start___kcrctab_unused_gpl,
446 module_assert_mutex_or_preempt();
448 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
451 list_for_each_entry_rcu(mod, &modules, list) {
452 struct symsearch arr[] = {
453 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
454 NOT_GPL_ONLY, false },
455 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
458 { mod->gpl_future_syms,
459 mod->gpl_future_syms + mod->num_gpl_future_syms,
460 mod->gpl_future_crcs,
461 WILL_BE_GPL_ONLY, false },
462 #ifdef CONFIG_UNUSED_SYMBOLS
464 mod->unused_syms + mod->num_unused_syms,
466 NOT_GPL_ONLY, true },
467 { mod->unused_gpl_syms,
468 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
469 mod->unused_gpl_crcs,
474 if (mod->state == MODULE_STATE_UNFORMED)
477 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
482 EXPORT_SYMBOL_GPL(each_symbol_section);
484 struct find_symbol_arg {
491 struct module *owner;
492 const unsigned long *crc;
493 const struct kernel_symbol *sym;
496 static bool check_symbol(const struct symsearch *syms,
497 struct module *owner,
498 unsigned int symnum, void *data)
500 struct find_symbol_arg *fsa = data;
503 if (syms->licence == GPL_ONLY)
505 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
506 pr_warn("Symbol %s is being used by a non-GPL module, "
507 "which will not be allowed in the future\n",
512 #ifdef CONFIG_UNUSED_SYMBOLS
513 if (syms->unused && fsa->warn) {
514 pr_warn("Symbol %s is marked as UNUSED, however this module is "
515 "using it.\n", fsa->name);
516 pr_warn("This symbol will go away in the future.\n");
517 pr_warn("Please evaluate if this is the right api to use and "
518 "if it really is, submit a report to the linux kernel "
519 "mailing list together with submitting your code for "
525 fsa->crc = symversion(syms->crcs, symnum);
526 fsa->sym = &syms->start[symnum];
530 static int cmp_name(const void *va, const void *vb)
533 const struct kernel_symbol *b;
535 return strcmp(a, b->name);
538 static bool find_symbol_in_section(const struct symsearch *syms,
539 struct module *owner,
542 struct find_symbol_arg *fsa = data;
543 struct kernel_symbol *sym;
545 sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
546 sizeof(struct kernel_symbol), cmp_name);
548 if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
554 /* Find a symbol and return it, along with, (optional) crc and
555 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
556 const struct kernel_symbol *find_symbol(const char *name,
557 struct module **owner,
558 const unsigned long **crc,
562 struct find_symbol_arg fsa;
568 if (each_symbol_section(find_symbol_in_section, &fsa)) {
576 pr_debug("Failed to find symbol %s\n", name);
579 EXPORT_SYMBOL_GPL(find_symbol);
582 * Search for module by name: must hold module_mutex (or preempt disabled
583 * for read-only access).
585 static struct module *find_module_all(const char *name, size_t len,
590 module_assert_mutex_or_preempt();
592 list_for_each_entry(mod, &modules, list) {
593 if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
595 if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
601 struct module *find_module(const char *name)
603 module_assert_mutex();
604 return find_module_all(name, strlen(name), false);
606 EXPORT_SYMBOL_GPL(find_module);
610 static inline void __percpu *mod_percpu(struct module *mod)
615 static int percpu_modalloc(struct module *mod, struct load_info *info)
617 Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
618 unsigned long align = pcpusec->sh_addralign;
620 if (!pcpusec->sh_size)
623 if (align > PAGE_SIZE) {
624 pr_warn("%s: per-cpu alignment %li > %li\n",
625 mod->name, align, PAGE_SIZE);
629 mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
631 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
632 mod->name, (unsigned long)pcpusec->sh_size);
635 mod->percpu_size = pcpusec->sh_size;
639 static void percpu_modfree(struct module *mod)
641 free_percpu(mod->percpu);
644 static unsigned int find_pcpusec(struct load_info *info)
646 return find_sec(info, ".data..percpu");
649 static void percpu_modcopy(struct module *mod,
650 const void *from, unsigned long size)
654 for_each_possible_cpu(cpu)
655 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
659 * is_module_percpu_address - test whether address is from module static percpu
660 * @addr: address to test
662 * Test whether @addr belongs to module static percpu area.
665 * %true if @addr is from module static percpu area
667 bool is_module_percpu_address(unsigned long addr)
674 list_for_each_entry_rcu(mod, &modules, list) {
675 if (mod->state == MODULE_STATE_UNFORMED)
677 if (!mod->percpu_size)
679 for_each_possible_cpu(cpu) {
680 void *start = per_cpu_ptr(mod->percpu, cpu);
682 if ((void *)addr >= start &&
683 (void *)addr < start + mod->percpu_size) {
694 #else /* ... !CONFIG_SMP */
696 static inline void __percpu *mod_percpu(struct module *mod)
700 static int percpu_modalloc(struct module *mod, struct load_info *info)
702 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
703 if (info->sechdrs[info->index.pcpu].sh_size != 0)
707 static inline void percpu_modfree(struct module *mod)
710 static unsigned int find_pcpusec(struct load_info *info)
714 static inline void percpu_modcopy(struct module *mod,
715 const void *from, unsigned long size)
717 /* pcpusec should be 0, and size of that section should be 0. */
720 bool is_module_percpu_address(unsigned long addr)
725 #endif /* CONFIG_SMP */
727 #define MODINFO_ATTR(field) \
728 static void setup_modinfo_##field(struct module *mod, const char *s) \
730 mod->field = kstrdup(s, GFP_KERNEL); \
732 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
733 struct module_kobject *mk, char *buffer) \
735 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
737 static int modinfo_##field##_exists(struct module *mod) \
739 return mod->field != NULL; \
741 static void free_modinfo_##field(struct module *mod) \
746 static struct module_attribute modinfo_##field = { \
747 .attr = { .name = __stringify(field), .mode = 0444 }, \
748 .show = show_modinfo_##field, \
749 .setup = setup_modinfo_##field, \
750 .test = modinfo_##field##_exists, \
751 .free = free_modinfo_##field, \
754 MODINFO_ATTR(version);
755 MODINFO_ATTR(srcversion);
757 static char last_unloaded_module[MODULE_NAME_LEN+1];
759 #ifdef CONFIG_MODULE_UNLOAD
761 EXPORT_TRACEPOINT_SYMBOL(module_get);
763 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
764 #define MODULE_REF_BASE 1
766 /* Init the unload section of the module. */
767 static int module_unload_init(struct module *mod)
770 * Initialize reference counter to MODULE_REF_BASE.
771 * refcnt == 0 means module is going.
773 atomic_set(&mod->refcnt, MODULE_REF_BASE);
775 INIT_LIST_HEAD(&mod->source_list);
776 INIT_LIST_HEAD(&mod->target_list);
778 /* Hold reference count during initialization. */
779 atomic_inc(&mod->refcnt);
784 /* Does a already use b? */
785 static int already_uses(struct module *a, struct module *b)
787 struct module_use *use;
789 list_for_each_entry(use, &b->source_list, source_list) {
790 if (use->source == a) {
791 pr_debug("%s uses %s!\n", a->name, b->name);
795 pr_debug("%s does not use %s!\n", a->name, b->name);
801 * - we add 'a' as a "source", 'b' as a "target" of module use
802 * - the module_use is added to the list of 'b' sources (so
803 * 'b' can walk the list to see who sourced them), and of 'a'
804 * targets (so 'a' can see what modules it targets).
806 static int add_module_usage(struct module *a, struct module *b)
808 struct module_use *use;
810 pr_debug("Allocating new usage for %s.\n", a->name);
811 use = kmalloc(sizeof(*use), GFP_ATOMIC);
813 pr_warn("%s: out of memory loading\n", a->name);
819 list_add(&use->source_list, &b->source_list);
820 list_add(&use->target_list, &a->target_list);
824 /* Module a uses b: caller needs module_mutex() */
825 int ref_module(struct module *a, struct module *b)
829 if (b == NULL || already_uses(a, b))
832 /* If module isn't available, we fail. */
833 err = strong_try_module_get(b);
837 err = add_module_usage(a, b);
844 EXPORT_SYMBOL_GPL(ref_module);
846 /* Clear the unload stuff of the module. */
847 static void module_unload_free(struct module *mod)
849 struct module_use *use, *tmp;
851 mutex_lock(&module_mutex);
852 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
853 struct module *i = use->target;
854 pr_debug("%s unusing %s\n", mod->name, i->name);
856 list_del(&use->source_list);
857 list_del(&use->target_list);
860 mutex_unlock(&module_mutex);
863 #ifdef CONFIG_MODULE_FORCE_UNLOAD
864 static inline int try_force_unload(unsigned int flags)
866 int ret = (flags & O_TRUNC);
868 add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
872 static inline int try_force_unload(unsigned int flags)
876 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
878 /* Try to release refcount of module, 0 means success. */
879 static int try_release_module_ref(struct module *mod)
883 /* Try to decrement refcnt which we set at loading */
884 ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
887 /* Someone can put this right now, recover with checking */
888 ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
893 static int try_stop_module(struct module *mod, int flags, int *forced)
895 /* If it's not unused, quit unless we're forcing. */
896 if (try_release_module_ref(mod) != 0) {
897 *forced = try_force_unload(flags);
902 /* Mark it as dying. */
903 mod->state = MODULE_STATE_GOING;
909 * module_refcount - return the refcount or -1 if unloading
911 * @mod: the module we're checking
914 * -1 if the module is in the process of unloading
915 * otherwise the number of references in the kernel to the module
917 int module_refcount(struct module *mod)
919 return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
921 EXPORT_SYMBOL(module_refcount);
923 /* This exists whether we can unload or not */
924 static void free_module(struct module *mod);
926 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
930 char name[MODULE_NAME_LEN];
933 if (!capable(CAP_SYS_MODULE) || modules_disabled)
936 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
938 name[MODULE_NAME_LEN-1] = '\0';
940 if (mutex_lock_interruptible(&module_mutex) != 0)
943 mod = find_module(name);
949 if (!list_empty(&mod->source_list)) {
950 /* Other modules depend on us: get rid of them first. */
955 /* Doing init or already dying? */
956 if (mod->state != MODULE_STATE_LIVE) {
957 /* FIXME: if (force), slam module count damn the torpedoes */
958 pr_debug("%s already dying\n", mod->name);
963 /* If it has an init func, it must have an exit func to unload */
964 if (mod->init && !mod->exit) {
965 forced = try_force_unload(flags);
967 /* This module can't be removed */
973 /* Stop the machine so refcounts can't move and disable module. */
974 ret = try_stop_module(mod, flags, &forced);
978 mutex_unlock(&module_mutex);
979 /* Final destruction now no one is using it. */
980 if (mod->exit != NULL)
982 blocking_notifier_call_chain(&module_notify_list,
983 MODULE_STATE_GOING, mod);
984 ftrace_release_mod(mod);
986 async_synchronize_full();
988 /* Store the name of the last unloaded module for diagnostic purposes */
989 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
994 mutex_unlock(&module_mutex);
998 static inline void print_unload_info(struct seq_file *m, struct module *mod)
1000 struct module_use *use;
1001 int printed_something = 0;
1003 seq_printf(m, " %i ", module_refcount(mod));
1006 * Always include a trailing , so userspace can differentiate
1007 * between this and the old multi-field proc format.
1009 list_for_each_entry(use, &mod->source_list, source_list) {
1010 printed_something = 1;
1011 seq_printf(m, "%s,", use->source->name);
1014 if (mod->init != NULL && mod->exit == NULL) {
1015 printed_something = 1;
1016 seq_puts(m, "[permanent],");
1019 if (!printed_something)
1023 void __symbol_put(const char *symbol)
1025 struct module *owner;
1028 if (!find_symbol(symbol, &owner, NULL, true, false))
1033 EXPORT_SYMBOL(__symbol_put);
1035 /* Note this assumes addr is a function, which it currently always is. */
1036 void symbol_put_addr(void *addr)
1038 struct module *modaddr;
1039 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
1041 if (core_kernel_text(a))
1045 * Even though we hold a reference on the module; we still need to
1046 * disable preemption in order to safely traverse the data structure.
1049 modaddr = __module_text_address(a);
1051 module_put(modaddr);
1054 EXPORT_SYMBOL_GPL(symbol_put_addr);
1056 static ssize_t show_refcnt(struct module_attribute *mattr,
1057 struct module_kobject *mk, char *buffer)
1059 return sprintf(buffer, "%i\n", module_refcount(mk->mod));
1062 static struct module_attribute modinfo_refcnt =
1063 __ATTR(refcnt, 0444, show_refcnt, NULL);
1065 void __module_get(struct module *module)
1069 atomic_inc(&module->refcnt);
1070 trace_module_get(module, _RET_IP_);
1074 EXPORT_SYMBOL(__module_get);
1076 bool try_module_get(struct module *module)
1082 /* Note: here, we can fail to get a reference */
1083 if (likely(module_is_live(module) &&
1084 atomic_inc_not_zero(&module->refcnt) != 0))
1085 trace_module_get(module, _RET_IP_);
1093 EXPORT_SYMBOL(try_module_get);
1095 void module_put(struct module *module)
1101 ret = atomic_dec_if_positive(&module->refcnt);
1102 WARN_ON(ret < 0); /* Failed to put refcount */
1103 trace_module_put(module, _RET_IP_);
1107 EXPORT_SYMBOL(module_put);
1109 #else /* !CONFIG_MODULE_UNLOAD */
1110 static inline void print_unload_info(struct seq_file *m, struct module *mod)
1112 /* We don't know the usage count, or what modules are using. */
1113 seq_puts(m, " - -");
1116 static inline void module_unload_free(struct module *mod)
1120 int ref_module(struct module *a, struct module *b)
1122 return strong_try_module_get(b);
1124 EXPORT_SYMBOL_GPL(ref_module);
1126 static inline int module_unload_init(struct module *mod)
1130 #endif /* CONFIG_MODULE_UNLOAD */
1132 static size_t module_flags_taint(struct module *mod, char *buf)
1136 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
1138 if (mod->taints & (1 << TAINT_OOT_MODULE))
1140 if (mod->taints & (1 << TAINT_FORCED_MODULE))
1142 if (mod->taints & (1 << TAINT_CRAP))
1144 if (mod->taints & (1 << TAINT_UNSIGNED_MODULE))
1147 * TAINT_FORCED_RMMOD: could be added.
1148 * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
1154 static ssize_t show_initstate(struct module_attribute *mattr,
1155 struct module_kobject *mk, char *buffer)
1157 const char *state = "unknown";
1159 switch (mk->mod->state) {
1160 case MODULE_STATE_LIVE:
1163 case MODULE_STATE_COMING:
1166 case MODULE_STATE_GOING:
1172 return sprintf(buffer, "%s\n", state);
1175 static struct module_attribute modinfo_initstate =
1176 __ATTR(initstate, 0444, show_initstate, NULL);
1178 static ssize_t store_uevent(struct module_attribute *mattr,
1179 struct module_kobject *mk,
1180 const char *buffer, size_t count)
1182 enum kobject_action action;
1184 if (kobject_action_type(buffer, count, &action) == 0)
1185 kobject_uevent(&mk->kobj, action);
1189 struct module_attribute module_uevent =
1190 __ATTR(uevent, 0200, NULL, store_uevent);
1192 static ssize_t show_coresize(struct module_attribute *mattr,
1193 struct module_kobject *mk, char *buffer)
1195 return sprintf(buffer, "%u\n", mk->mod->core_layout.size);
1198 static struct module_attribute modinfo_coresize =
1199 __ATTR(coresize, 0444, show_coresize, NULL);
1201 static ssize_t show_initsize(struct module_attribute *mattr,
1202 struct module_kobject *mk, char *buffer)
1204 return sprintf(buffer, "%u\n", mk->mod->init_layout.size);
1207 static struct module_attribute modinfo_initsize =
1208 __ATTR(initsize, 0444, show_initsize, NULL);
1210 static ssize_t show_taint(struct module_attribute *mattr,
1211 struct module_kobject *mk, char *buffer)
1215 l = module_flags_taint(mk->mod, buffer);
1220 static struct module_attribute modinfo_taint =
1221 __ATTR(taint, 0444, show_taint, NULL);
1223 static struct module_attribute *modinfo_attrs[] = {
1226 &modinfo_srcversion,
1231 #ifdef CONFIG_MODULE_UNLOAD
1237 static const char vermagic[] = VERMAGIC_STRING;
1239 static int try_to_force_load(struct module *mod, const char *reason)
1241 #ifdef CONFIG_MODULE_FORCE_LOAD
1242 if (!test_taint(TAINT_FORCED_MODULE))
1243 pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
1244 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
1251 #ifdef CONFIG_MODVERSIONS
1252 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
1253 static unsigned long maybe_relocated(unsigned long crc,
1254 const struct module *crc_owner)
1256 #ifdef ARCH_RELOCATES_KCRCTAB
1257 if (crc_owner == NULL)
1258 return crc - (unsigned long)reloc_start;
1263 static int check_version(Elf_Shdr *sechdrs,
1264 unsigned int versindex,
1265 const char *symname,
1267 const unsigned long *crc,
1268 const struct module *crc_owner)
1270 unsigned int i, num_versions;
1271 struct modversion_info *versions;
1273 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1277 /* No versions at all? modprobe --force does this. */
1279 return try_to_force_load(mod, symname) == 0;
1281 versions = (void *) sechdrs[versindex].sh_addr;
1282 num_versions = sechdrs[versindex].sh_size
1283 / sizeof(struct modversion_info);
1285 for (i = 0; i < num_versions; i++) {
1286 if (strcmp(versions[i].name, symname) != 0)
1289 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
1291 pr_debug("Found checksum %lX vs module %lX\n",
1292 maybe_relocated(*crc, crc_owner), versions[i].crc);
1296 pr_warn("%s: no symbol version for %s\n", mod->name, symname);
1300 pr_warn("%s: disagrees about version of symbol %s\n",
1301 mod->name, symname);
1305 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1306 unsigned int versindex,
1309 const unsigned long *crc;
1312 * Since this should be found in kernel (which can't be removed), no
1313 * locking is necessary -- use preempt_disable() to placate lockdep.
1316 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
1317 &crc, true, false)) {
1322 return check_version(sechdrs, versindex,
1323 VMLINUX_SYMBOL_STR(module_layout), mod, crc,
1327 /* First part is kernel version, which we ignore if module has crcs. */
1328 static inline int same_magic(const char *amagic, const char *bmagic,
1332 amagic += strcspn(amagic, " ");
1333 bmagic += strcspn(bmagic, " ");
1335 return strcmp(amagic, bmagic) == 0;
1338 static inline int check_version(Elf_Shdr *sechdrs,
1339 unsigned int versindex,
1340 const char *symname,
1342 const unsigned long *crc,
1343 const struct module *crc_owner)
1348 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1349 unsigned int versindex,
1355 static inline int same_magic(const char *amagic, const char *bmagic,
1358 return strcmp(amagic, bmagic) == 0;
1360 #endif /* CONFIG_MODVERSIONS */
1362 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1363 static const struct kernel_symbol *resolve_symbol(struct module *mod,
1364 const struct load_info *info,
1368 struct module *owner;
1369 const struct kernel_symbol *sym;
1370 const unsigned long *crc;
1374 * The module_mutex should not be a heavily contended lock;
1375 * if we get the occasional sleep here, we'll go an extra iteration
1376 * in the wait_event_interruptible(), which is harmless.
1378 sched_annotate_sleep();
1379 mutex_lock(&module_mutex);
1380 sym = find_symbol(name, &owner, &crc,
1381 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1385 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1387 sym = ERR_PTR(-EINVAL);
1391 err = ref_module(mod, owner);
1398 /* We must make copy under the lock if we failed to get ref. */
1399 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1401 mutex_unlock(&module_mutex);
1405 static const struct kernel_symbol *
1406 resolve_symbol_wait(struct module *mod,
1407 const struct load_info *info,
1410 const struct kernel_symbol *ksym;
1411 char owner[MODULE_NAME_LEN];
1413 if (wait_event_interruptible_timeout(module_wq,
1414 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1415 || PTR_ERR(ksym) != -EBUSY,
1417 pr_warn("%s: gave up waiting for init of module %s.\n",
1424 * /sys/module/foo/sections stuff
1425 * J. Corbet <corbet@lwn.net>
1429 #ifdef CONFIG_KALLSYMS
1430 static inline bool sect_empty(const Elf_Shdr *sect)
1432 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1435 struct module_sect_attr {
1436 struct module_attribute mattr;
1438 unsigned long address;
1441 struct module_sect_attrs {
1442 struct attribute_group grp;
1443 unsigned int nsections;
1444 struct module_sect_attr attrs[0];
1447 static ssize_t module_sect_show(struct module_attribute *mattr,
1448 struct module_kobject *mk, char *buf)
1450 struct module_sect_attr *sattr =
1451 container_of(mattr, struct module_sect_attr, mattr);
1452 return sprintf(buf, "0x%pK\n", (void *)sattr->address);
1455 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1457 unsigned int section;
1459 for (section = 0; section < sect_attrs->nsections; section++)
1460 kfree(sect_attrs->attrs[section].name);
1464 static void add_sect_attrs(struct module *mod, const struct load_info *info)
1466 unsigned int nloaded = 0, i, size[2];
1467 struct module_sect_attrs *sect_attrs;
1468 struct module_sect_attr *sattr;
1469 struct attribute **gattr;
1471 /* Count loaded sections and allocate structures */
1472 for (i = 0; i < info->hdr->e_shnum; i++)
1473 if (!sect_empty(&info->sechdrs[i]))
1475 size[0] = ALIGN(sizeof(*sect_attrs)
1476 + nloaded * sizeof(sect_attrs->attrs[0]),
1477 sizeof(sect_attrs->grp.attrs[0]));
1478 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1479 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1480 if (sect_attrs == NULL)
1483 /* Setup section attributes. */
1484 sect_attrs->grp.name = "sections";
1485 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1487 sect_attrs->nsections = 0;
1488 sattr = §_attrs->attrs[0];
1489 gattr = §_attrs->grp.attrs[0];
1490 for (i = 0; i < info->hdr->e_shnum; i++) {
1491 Elf_Shdr *sec = &info->sechdrs[i];
1492 if (sect_empty(sec))
1494 sattr->address = sec->sh_addr;
1495 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1497 if (sattr->name == NULL)
1499 sect_attrs->nsections++;
1500 sysfs_attr_init(&sattr->mattr.attr);
1501 sattr->mattr.show = module_sect_show;
1502 sattr->mattr.store = NULL;
1503 sattr->mattr.attr.name = sattr->name;
1504 sattr->mattr.attr.mode = S_IRUGO;
1505 *(gattr++) = &(sattr++)->mattr.attr;
1509 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1512 mod->sect_attrs = sect_attrs;
1515 free_sect_attrs(sect_attrs);
1518 static void remove_sect_attrs(struct module *mod)
1520 if (mod->sect_attrs) {
1521 sysfs_remove_group(&mod->mkobj.kobj,
1522 &mod->sect_attrs->grp);
1523 /* We are positive that no one is using any sect attrs
1524 * at this point. Deallocate immediately. */
1525 free_sect_attrs(mod->sect_attrs);
1526 mod->sect_attrs = NULL;
1531 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1534 struct module_notes_attrs {
1535 struct kobject *dir;
1537 struct bin_attribute attrs[0];
1540 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1541 struct bin_attribute *bin_attr,
1542 char *buf, loff_t pos, size_t count)
1545 * The caller checked the pos and count against our size.
1547 memcpy(buf, bin_attr->private + pos, count);
1551 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1554 if (notes_attrs->dir) {
1556 sysfs_remove_bin_file(notes_attrs->dir,
1557 ¬es_attrs->attrs[i]);
1558 kobject_put(notes_attrs->dir);
1563 static void add_notes_attrs(struct module *mod, const struct load_info *info)
1565 unsigned int notes, loaded, i;
1566 struct module_notes_attrs *notes_attrs;
1567 struct bin_attribute *nattr;
1569 /* failed to create section attributes, so can't create notes */
1570 if (!mod->sect_attrs)
1573 /* Count notes sections and allocate structures. */
1575 for (i = 0; i < info->hdr->e_shnum; i++)
1576 if (!sect_empty(&info->sechdrs[i]) &&
1577 (info->sechdrs[i].sh_type == SHT_NOTE))
1583 notes_attrs = kzalloc(sizeof(*notes_attrs)
1584 + notes * sizeof(notes_attrs->attrs[0]),
1586 if (notes_attrs == NULL)
1589 notes_attrs->notes = notes;
1590 nattr = ¬es_attrs->attrs[0];
1591 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1592 if (sect_empty(&info->sechdrs[i]))
1594 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1595 sysfs_bin_attr_init(nattr);
1596 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1597 nattr->attr.mode = S_IRUGO;
1598 nattr->size = info->sechdrs[i].sh_size;
1599 nattr->private = (void *) info->sechdrs[i].sh_addr;
1600 nattr->read = module_notes_read;
1606 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1607 if (!notes_attrs->dir)
1610 for (i = 0; i < notes; ++i)
1611 if (sysfs_create_bin_file(notes_attrs->dir,
1612 ¬es_attrs->attrs[i]))
1615 mod->notes_attrs = notes_attrs;
1619 free_notes_attrs(notes_attrs, i);
1622 static void remove_notes_attrs(struct module *mod)
1624 if (mod->notes_attrs)
1625 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1630 static inline void add_sect_attrs(struct module *mod,
1631 const struct load_info *info)
1635 static inline void remove_sect_attrs(struct module *mod)
1639 static inline void add_notes_attrs(struct module *mod,
1640 const struct load_info *info)
1644 static inline void remove_notes_attrs(struct module *mod)
1647 #endif /* CONFIG_KALLSYMS */
1649 static void add_usage_links(struct module *mod)
1651 #ifdef CONFIG_MODULE_UNLOAD
1652 struct module_use *use;
1655 mutex_lock(&module_mutex);
1656 list_for_each_entry(use, &mod->target_list, target_list) {
1657 nowarn = sysfs_create_link(use->target->holders_dir,
1658 &mod->mkobj.kobj, mod->name);
1660 mutex_unlock(&module_mutex);
1664 static void del_usage_links(struct module *mod)
1666 #ifdef CONFIG_MODULE_UNLOAD
1667 struct module_use *use;
1669 mutex_lock(&module_mutex);
1670 list_for_each_entry(use, &mod->target_list, target_list)
1671 sysfs_remove_link(use->target->holders_dir, mod->name);
1672 mutex_unlock(&module_mutex);
1676 static int module_add_modinfo_attrs(struct module *mod)
1678 struct module_attribute *attr;
1679 struct module_attribute *temp_attr;
1683 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1684 (ARRAY_SIZE(modinfo_attrs) + 1)),
1686 if (!mod->modinfo_attrs)
1689 temp_attr = mod->modinfo_attrs;
1690 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1692 (attr->test && attr->test(mod))) {
1693 memcpy(temp_attr, attr, sizeof(*temp_attr));
1694 sysfs_attr_init(&temp_attr->attr);
1695 error = sysfs_create_file(&mod->mkobj.kobj,
1703 static void module_remove_modinfo_attrs(struct module *mod)
1705 struct module_attribute *attr;
1708 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1709 /* pick a field to test for end of list */
1710 if (!attr->attr.name)
1712 sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
1716 kfree(mod->modinfo_attrs);
1719 static void mod_kobject_put(struct module *mod)
1721 DECLARE_COMPLETION_ONSTACK(c);
1722 mod->mkobj.kobj_completion = &c;
1723 kobject_put(&mod->mkobj.kobj);
1724 wait_for_completion(&c);
1727 static int mod_sysfs_init(struct module *mod)
1730 struct kobject *kobj;
1732 if (!module_sysfs_initialized) {
1733 pr_err("%s: module sysfs not initialized\n", mod->name);
1738 kobj = kset_find_obj(module_kset, mod->name);
1740 pr_err("%s: module is already loaded\n", mod->name);
1746 mod->mkobj.mod = mod;
1748 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1749 mod->mkobj.kobj.kset = module_kset;
1750 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1753 mod_kobject_put(mod);
1755 /* delay uevent until full sysfs population */
1760 static int mod_sysfs_setup(struct module *mod,
1761 const struct load_info *info,
1762 struct kernel_param *kparam,
1763 unsigned int num_params)
1767 err = mod_sysfs_init(mod);
1771 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1772 if (!mod->holders_dir) {
1777 err = module_param_sysfs_setup(mod, kparam, num_params);
1779 goto out_unreg_holders;
1781 err = module_add_modinfo_attrs(mod);
1783 goto out_unreg_param;
1785 add_usage_links(mod);
1786 add_sect_attrs(mod, info);
1787 add_notes_attrs(mod, info);
1789 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1793 module_param_sysfs_remove(mod);
1795 kobject_put(mod->holders_dir);
1797 mod_kobject_put(mod);
1802 static void mod_sysfs_fini(struct module *mod)
1804 remove_notes_attrs(mod);
1805 remove_sect_attrs(mod);
1806 mod_kobject_put(mod);
1809 static void init_param_lock(struct module *mod)
1811 mutex_init(&mod->param_lock);
1813 #else /* !CONFIG_SYSFS */
1815 static int mod_sysfs_setup(struct module *mod,
1816 const struct load_info *info,
1817 struct kernel_param *kparam,
1818 unsigned int num_params)
1823 static void mod_sysfs_fini(struct module *mod)
1827 static void module_remove_modinfo_attrs(struct module *mod)
1831 static void del_usage_links(struct module *mod)
1835 static void init_param_lock(struct module *mod)
1838 #endif /* CONFIG_SYSFS */
1840 static void mod_sysfs_teardown(struct module *mod)
1842 del_usage_links(mod);
1843 module_remove_modinfo_attrs(mod);
1844 module_param_sysfs_remove(mod);
1845 kobject_put(mod->mkobj.drivers_dir);
1846 kobject_put(mod->holders_dir);
1847 mod_sysfs_fini(mod);
1850 #ifdef CONFIG_DEBUG_SET_MODULE_RONX
1852 * LKM RO/NX protection: protect module's text/ro-data
1853 * from modification and any data from execution.
1855 * General layout of module is:
1856 * [text] [read-only-data] [writable data]
1857 * text_size -----^ ^ ^
1858 * ro_size ------------------------| |
1859 * size -------------------------------------------|
1861 * These values are always page-aligned (as is base)
1863 static void frob_text(const struct module_layout *layout,
1864 int (*set_memory)(unsigned long start, int num_pages))
1866 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1867 BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
1868 set_memory((unsigned long)layout->base,
1869 layout->text_size >> PAGE_SHIFT);
1872 static void frob_rodata(const struct module_layout *layout,
1873 int (*set_memory)(unsigned long start, int num_pages))
1875 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1876 BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
1877 BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
1878 set_memory((unsigned long)layout->base + layout->text_size,
1879 (layout->ro_size - layout->text_size) >> PAGE_SHIFT);
1882 static void frob_writable_data(const struct module_layout *layout,
1883 int (*set_memory)(unsigned long start, int num_pages))
1885 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1886 BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
1887 BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1));
1888 set_memory((unsigned long)layout->base + layout->ro_size,
1889 (layout->size - layout->ro_size) >> PAGE_SHIFT);
1892 /* livepatching wants to disable read-only so it can frob module. */
1893 void module_disable_ro(const struct module *mod)
1895 frob_text(&mod->core_layout, set_memory_rw);
1896 frob_rodata(&mod->core_layout, set_memory_rw);
1897 frob_text(&mod->init_layout, set_memory_rw);
1898 frob_rodata(&mod->init_layout, set_memory_rw);
1901 void module_enable_ro(const struct module *mod)
1903 frob_text(&mod->core_layout, set_memory_ro);
1904 frob_rodata(&mod->core_layout, set_memory_ro);
1905 frob_text(&mod->init_layout, set_memory_ro);
1906 frob_rodata(&mod->init_layout, set_memory_ro);
1909 static void module_enable_nx(const struct module *mod)
1911 frob_rodata(&mod->core_layout, set_memory_nx);
1912 frob_writable_data(&mod->core_layout, set_memory_nx);
1913 frob_rodata(&mod->init_layout, set_memory_nx);
1914 frob_writable_data(&mod->init_layout, set_memory_nx);
1917 static void module_disable_nx(const struct module *mod)
1919 frob_rodata(&mod->core_layout, set_memory_x);
1920 frob_writable_data(&mod->core_layout, set_memory_x);
1921 frob_rodata(&mod->init_layout, set_memory_x);
1922 frob_writable_data(&mod->init_layout, set_memory_x);
1925 /* Iterate through all modules and set each module's text as RW */
1926 void set_all_modules_text_rw(void)
1930 mutex_lock(&module_mutex);
1931 list_for_each_entry_rcu(mod, &modules, list) {
1932 if (mod->state == MODULE_STATE_UNFORMED)
1935 frob_text(&mod->core_layout, set_memory_rw);
1936 frob_text(&mod->init_layout, set_memory_rw);
1938 mutex_unlock(&module_mutex);
1941 /* Iterate through all modules and set each module's text as RO */
1942 void set_all_modules_text_ro(void)
1946 mutex_lock(&module_mutex);
1947 list_for_each_entry_rcu(mod, &modules, list) {
1948 if (mod->state == MODULE_STATE_UNFORMED)
1951 frob_text(&mod->core_layout, set_memory_ro);
1952 frob_text(&mod->init_layout, set_memory_ro);
1954 mutex_unlock(&module_mutex);
1957 static void disable_ro_nx(const struct module_layout *layout)
1959 frob_text(layout, set_memory_rw);
1960 frob_rodata(layout, set_memory_rw);
1961 frob_rodata(layout, set_memory_x);
1962 frob_writable_data(layout, set_memory_x);
1966 static void disable_ro_nx(const struct module_layout *layout) { }
1967 static void module_enable_nx(const struct module *mod) { }
1968 static void module_disable_nx(const struct module *mod) { }
1971 void __weak module_memfree(void *module_region)
1973 vfree(module_region);
1976 void __weak module_arch_cleanup(struct module *mod)
1980 void __weak module_arch_freeing_init(struct module *mod)
1984 /* Free a module, remove from lists, etc. */
1985 static void free_module(struct module *mod)
1987 trace_module_free(mod);
1989 mod_sysfs_teardown(mod);
1991 /* We leave it in list to prevent duplicate loads, but make sure
1992 * that noone uses it while it's being deconstructed. */
1993 mutex_lock(&module_mutex);
1994 mod->state = MODULE_STATE_UNFORMED;
1995 mutex_unlock(&module_mutex);
1997 /* Remove dynamic debug info */
1998 ddebug_remove_module(mod->name);
2000 /* Arch-specific cleanup. */
2001 module_arch_cleanup(mod);
2003 /* Module unload stuff */
2004 module_unload_free(mod);
2006 /* Free any allocated parameters. */
2007 destroy_params(mod->kp, mod->num_kp);
2009 /* Now we can delete it from the lists */
2010 mutex_lock(&module_mutex);
2011 /* Unlink carefully: kallsyms could be walking list. */
2012 list_del_rcu(&mod->list);
2013 mod_tree_remove(mod);
2014 /* Remove this module from bug list, this uses list_del_rcu */
2015 module_bug_cleanup(mod);
2016 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2017 synchronize_sched();
2018 mutex_unlock(&module_mutex);
2020 /* This may be empty, but that's OK */
2021 disable_ro_nx(&mod->init_layout);
2022 module_arch_freeing_init(mod);
2023 module_memfree(mod->init_layout.base);
2025 percpu_modfree(mod);
2027 /* Free lock-classes; relies on the preceding sync_rcu(). */
2028 lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
2030 /* Finally, free the core (containing the module structure) */
2031 disable_ro_nx(&mod->core_layout);
2032 module_memfree(mod->core_layout.base);
2035 update_protections(current->mm);
2039 void *__symbol_get(const char *symbol)
2041 struct module *owner;
2042 const struct kernel_symbol *sym;
2045 sym = find_symbol(symbol, &owner, NULL, true, true);
2046 if (sym && strong_try_module_get(owner))
2050 return sym ? (void *)sym->value : NULL;
2052 EXPORT_SYMBOL_GPL(__symbol_get);
2055 * Ensure that an exported symbol [global namespace] does not already exist
2056 * in the kernel or in some other module's exported symbol table.
2058 * You must hold the module_mutex.
2060 static int verify_export_symbols(struct module *mod)
2063 struct module *owner;
2064 const struct kernel_symbol *s;
2066 const struct kernel_symbol *sym;
2069 { mod->syms, mod->num_syms },
2070 { mod->gpl_syms, mod->num_gpl_syms },
2071 { mod->gpl_future_syms, mod->num_gpl_future_syms },
2072 #ifdef CONFIG_UNUSED_SYMBOLS
2073 { mod->unused_syms, mod->num_unused_syms },
2074 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
2078 for (i = 0; i < ARRAY_SIZE(arr); i++) {
2079 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
2080 if (find_symbol(s->name, &owner, NULL, true, false)) {
2081 pr_err("%s: exports duplicate symbol %s"
2083 mod->name, s->name, module_name(owner));
2091 /* Change all symbols so that st_value encodes the pointer directly. */
2092 static int simplify_symbols(struct module *mod, const struct load_info *info)
2094 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2095 Elf_Sym *sym = (void *)symsec->sh_addr;
2096 unsigned long secbase;
2099 const struct kernel_symbol *ksym;
2101 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
2102 const char *name = info->strtab + sym[i].st_name;
2104 switch (sym[i].st_shndx) {
2106 /* Ignore common symbols */
2107 if (!strncmp(name, "__gnu_lto", 9))
2110 /* We compiled with -fno-common. These are not
2111 supposed to happen. */
2112 pr_debug("Common symbol: %s\n", name);
2113 pr_warn("%s: please compile with -fno-common\n",
2119 /* Don't need to do anything */
2120 pr_debug("Absolute symbol: 0x%08lx\n",
2121 (long)sym[i].st_value);
2125 ksym = resolve_symbol_wait(mod, info, name);
2126 /* Ok if resolved. */
2127 if (ksym && !IS_ERR(ksym)) {
2128 sym[i].st_value = ksym->value;
2133 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
2136 pr_warn("%s: Unknown symbol %s (err %li)\n",
2137 mod->name, name, PTR_ERR(ksym));
2138 ret = PTR_ERR(ksym) ?: -ENOENT;
2142 /* Divert to percpu allocation if a percpu var. */
2143 if (sym[i].st_shndx == info->index.pcpu)
2144 secbase = (unsigned long)mod_percpu(mod);
2146 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
2147 sym[i].st_value += secbase;
2155 static int apply_relocations(struct module *mod, const struct load_info *info)
2160 /* Now do relocations. */
2161 for (i = 1; i < info->hdr->e_shnum; i++) {
2162 unsigned int infosec = info->sechdrs[i].sh_info;
2164 /* Not a valid relocation section? */
2165 if (infosec >= info->hdr->e_shnum)
2168 /* Don't bother with non-allocated sections */
2169 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
2172 if (info->sechdrs[i].sh_type == SHT_REL)
2173 err = apply_relocate(info->sechdrs, info->strtab,
2174 info->index.sym, i, mod);
2175 else if (info->sechdrs[i].sh_type == SHT_RELA)
2176 err = apply_relocate_add(info->sechdrs, info->strtab,
2177 info->index.sym, i, mod);
2184 /* Additional bytes needed by arch in front of individual sections */
2185 unsigned int __weak arch_mod_section_prepend(struct module *mod,
2186 unsigned int section)
2188 /* default implementation just returns zero */
2192 /* Update size with this section: return offset. */
2193 static long get_offset(struct module *mod, unsigned int *size,
2194 Elf_Shdr *sechdr, unsigned int section)
2198 *size += arch_mod_section_prepend(mod, section);
2199 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2200 *size = ret + sechdr->sh_size;
2204 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2205 might -- code, read-only data, read-write data, small data. Tally
2206 sizes, and place the offsets into sh_entsize fields: high bit means it
2208 static void layout_sections(struct module *mod, struct load_info *info)
2210 static unsigned long const masks[][2] = {
2211 /* NOTE: all executable code must be the first section
2212 * in this array; otherwise modify the text_size
2213 * finder in the two loops below */
2214 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2215 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
2216 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2217 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2221 for (i = 0; i < info->hdr->e_shnum; i++)
2222 info->sechdrs[i].sh_entsize = ~0UL;
2224 pr_debug("Core section allocation order:\n");
2225 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2226 for (i = 0; i < info->hdr->e_shnum; ++i) {
2227 Elf_Shdr *s = &info->sechdrs[i];
2228 const char *sname = info->secstrings + s->sh_name;
2230 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2231 || (s->sh_flags & masks[m][1])
2232 || s->sh_entsize != ~0UL
2233 || strstarts(sname, ".init"))
2235 s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i);
2236 pr_debug("\t%s\n", sname);
2239 case 0: /* executable */
2240 mod->core_layout.size = debug_align(mod->core_layout.size);
2241 mod->core_layout.text_size = mod->core_layout.size;
2243 case 1: /* RO: text and ro-data */
2244 mod->core_layout.size = debug_align(mod->core_layout.size);
2245 mod->core_layout.ro_size = mod->core_layout.size;
2247 case 3: /* whole core */
2248 mod->core_layout.size = debug_align(mod->core_layout.size);
2253 pr_debug("Init section allocation order:\n");
2254 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2255 for (i = 0; i < info->hdr->e_shnum; ++i) {
2256 Elf_Shdr *s = &info->sechdrs[i];
2257 const char *sname = info->secstrings + s->sh_name;
2259 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2260 || (s->sh_flags & masks[m][1])
2261 || s->sh_entsize != ~0UL
2262 || !strstarts(sname, ".init"))
2264 s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i)
2265 | INIT_OFFSET_MASK);
2266 pr_debug("\t%s\n", sname);
2269 case 0: /* executable */
2270 mod->init_layout.size = debug_align(mod->init_layout.size);
2271 mod->init_layout.text_size = mod->init_layout.size;
2273 case 1: /* RO: text and ro-data */
2274 mod->init_layout.size = debug_align(mod->init_layout.size);
2275 mod->init_layout.ro_size = mod->init_layout.size;
2277 case 3: /* whole init */
2278 mod->init_layout.size = debug_align(mod->init_layout.size);
2284 static void set_license(struct module *mod, const char *license)
2287 license = "unspecified";
2289 if (!license_is_gpl_compatible(license)) {
2290 if (!test_taint(TAINT_PROPRIETARY_MODULE))
2291 pr_warn("%s: module license '%s' taints kernel.\n",
2292 mod->name, license);
2293 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2294 LOCKDEP_NOW_UNRELIABLE);
2298 /* Parse tag=value strings from .modinfo section */
2299 static char *next_string(char *string, unsigned long *secsize)
2301 /* Skip non-zero chars */
2304 if ((*secsize)-- <= 1)
2308 /* Skip any zero padding. */
2309 while (!string[0]) {
2311 if ((*secsize)-- <= 1)
2317 static char *get_modinfo(struct load_info *info, const char *tag)
2320 unsigned int taglen = strlen(tag);
2321 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2322 unsigned long size = infosec->sh_size;
2324 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
2325 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2326 return p + taglen + 1;
2331 static void setup_modinfo(struct module *mod, struct load_info *info)
2333 struct module_attribute *attr;
2336 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2338 attr->setup(mod, get_modinfo(info, attr->attr.name));
2342 static void free_modinfo(struct module *mod)
2344 struct module_attribute *attr;
2347 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2353 #ifdef CONFIG_KALLSYMS
2355 /* lookup symbol in given range of kernel_symbols */
2356 static const struct kernel_symbol *lookup_symbol(const char *name,
2357 const struct kernel_symbol *start,
2358 const struct kernel_symbol *stop)
2360 return bsearch(name, start, stop - start,
2361 sizeof(struct kernel_symbol), cmp_name);
2364 static int is_exported(const char *name, unsigned long value,
2365 const struct module *mod)
2367 const struct kernel_symbol *ks;
2369 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
2371 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
2372 return ks != NULL && ks->value == value;
2376 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
2378 const Elf_Shdr *sechdrs = info->sechdrs;
2380 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2381 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2386 if (sym->st_shndx == SHN_UNDEF)
2388 if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu)
2390 if (sym->st_shndx >= SHN_LORESERVE)
2392 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2394 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2395 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2396 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2398 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2403 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2404 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2409 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2416 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
2417 unsigned int shnum, unsigned int pcpundx)
2419 const Elf_Shdr *sec;
2421 if (src->st_shndx == SHN_UNDEF
2422 || src->st_shndx >= shnum
2426 #ifdef CONFIG_KALLSYMS_ALL
2427 if (src->st_shndx == pcpundx)
2431 sec = sechdrs + src->st_shndx;
2432 if (!(sec->sh_flags & SHF_ALLOC)
2433 #ifndef CONFIG_KALLSYMS_ALL
2434 || !(sec->sh_flags & SHF_EXECINSTR)
2436 || (sec->sh_entsize & INIT_OFFSET_MASK))
2443 * We only allocate and copy the strings needed by the parts of symtab
2444 * we keep. This is simple, but has the effect of making multiple
2445 * copies of duplicates. We could be more sophisticated, see
2446 * linux-kernel thread starting with
2447 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2449 static void layout_symtab(struct module *mod, struct load_info *info)
2451 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2452 Elf_Shdr *strsect = info->sechdrs + info->index.str;
2454 unsigned int i, nsrc, ndst, strtab_size = 0;
2456 /* Put symbol section at end of init part of module. */
2457 symsect->sh_flags |= SHF_ALLOC;
2458 symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect,
2459 info->index.sym) | INIT_OFFSET_MASK;
2460 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
2462 src = (void *)info->hdr + symsect->sh_offset;
2463 nsrc = symsect->sh_size / sizeof(*src);
2465 /* Compute total space required for the core symbols' strtab. */
2466 for (ndst = i = 0; i < nsrc; i++) {
2468 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
2469 info->index.pcpu)) {
2470 strtab_size += strlen(&info->strtab[src[i].st_name])+1;
2475 /* Append room for core symbols at end of core part. */
2476 info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1);
2477 info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym);
2478 mod->core_layout.size += strtab_size;
2479 mod->core_layout.size = debug_align(mod->core_layout.size);
2481 /* Put string table section at end of init part of module. */
2482 strsect->sh_flags |= SHF_ALLOC;
2483 strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect,
2484 info->index.str) | INIT_OFFSET_MASK;
2485 mod->init_layout.size = debug_align(mod->init_layout.size);
2486 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
2489 static void add_kallsyms(struct module *mod, const struct load_info *info)
2491 unsigned int i, ndst;
2495 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2497 mod->symtab = (void *)symsec->sh_addr;
2498 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2499 /* Make sure we get permanent strtab: don't use info->strtab. */
2500 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2502 /* Set types up while we still have access to sections. */
2503 for (i = 0; i < mod->num_symtab; i++)
2504 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
2506 mod->core_symtab = dst = mod->core_layout.base + info->symoffs;
2507 mod->core_strtab = s = mod->core_layout.base + info->stroffs;
2509 for (ndst = i = 0; i < mod->num_symtab; i++) {
2511 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
2512 info->index.pcpu)) {
2514 dst[ndst++].st_name = s - mod->core_strtab;
2515 s += strlcpy(s, &mod->strtab[src[i].st_name],
2519 mod->core_num_syms = ndst;
2522 static inline void layout_symtab(struct module *mod, struct load_info *info)
2526 static void add_kallsyms(struct module *mod, const struct load_info *info)
2529 #endif /* CONFIG_KALLSYMS */
2531 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2535 #ifdef CONFIG_DYNAMIC_DEBUG
2536 if (ddebug_add_module(debug, num, debug->modname))
2537 pr_err("dynamic debug error adding module: %s\n",
2542 static void dynamic_debug_remove(struct _ddebug *debug)
2545 ddebug_remove_module(debug->modname);
2548 void * __weak module_alloc(unsigned long size)
2550 return vmalloc_exec(size);
2553 #ifdef CONFIG_DEBUG_KMEMLEAK
2554 static void kmemleak_load_module(const struct module *mod,
2555 const struct load_info *info)
2559 /* only scan the sections containing data */
2560 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2562 for (i = 1; i < info->hdr->e_shnum; i++) {
2563 /* Scan all writable sections that's not executable */
2564 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
2565 !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
2566 (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
2569 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2570 info->sechdrs[i].sh_size, GFP_KERNEL);
2574 static inline void kmemleak_load_module(const struct module *mod,
2575 const struct load_info *info)
2580 #ifdef CONFIG_MODULE_SIG
2581 static int module_sig_check(struct load_info *info)
2584 const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2585 const void *mod = info->hdr;
2587 if (info->len > markerlen &&
2588 memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
2589 /* We truncate the module to discard the signature */
2590 info->len -= markerlen;
2591 err = mod_verify_sig(mod, &info->len);
2595 info->sig_ok = true;
2599 /* Not having a signature is only an error if we're strict. */
2600 if (err == -ENOKEY && !sig_enforce)
2605 #else /* !CONFIG_MODULE_SIG */
2606 static int module_sig_check(struct load_info *info)
2610 #endif /* !CONFIG_MODULE_SIG */
2612 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2613 static int elf_header_check(struct load_info *info)
2615 if (info->len < sizeof(*(info->hdr)))
2618 if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2619 || info->hdr->e_type != ET_REL
2620 || !elf_check_arch(info->hdr)
2621 || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2624 if (info->hdr->e_shoff >= info->len
2625 || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2626 info->len - info->hdr->e_shoff))
2632 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2634 static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len)
2637 unsigned long n = min(len, COPY_CHUNK_SIZE);
2639 if (copy_from_user(dst, usrc, n) != 0)
2649 /* Sets info->hdr and info->len. */
2650 static int copy_module_from_user(const void __user *umod, unsigned long len,
2651 struct load_info *info)
2656 if (info->len < sizeof(*(info->hdr)))
2659 err = security_kernel_module_from_file(NULL);
2663 /* Suck in entire file: we'll want most of it. */
2664 info->hdr = __vmalloc(info->len,
2665 GFP_KERNEL | __GFP_HIGHMEM | __GFP_NOWARN, PAGE_KERNEL);
2669 if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
2677 /* Sets info->hdr and info->len. */
2678 static int copy_module_from_fd(int fd, struct load_info *info)
2680 struct fd f = fdget(fd);
2689 err = security_kernel_module_from_file(f.file);
2693 err = vfs_getattr(&f.file->f_path, &stat);
2697 if (stat.size > INT_MAX) {
2702 /* Don't hand 0 to vmalloc, it whines. */
2703 if (stat.size == 0) {
2708 info->hdr = vmalloc(stat.size);
2715 while (pos < stat.size) {
2716 bytes = kernel_read(f.file, pos, (char *)(info->hdr) + pos,
2734 static void free_copy(struct load_info *info)
2739 static int rewrite_section_headers(struct load_info *info, int flags)
2743 /* This should always be true, but let's be sure. */
2744 info->sechdrs[0].sh_addr = 0;
2746 for (i = 1; i < info->hdr->e_shnum; i++) {
2747 Elf_Shdr *shdr = &info->sechdrs[i];
2748 if (shdr->sh_type != SHT_NOBITS
2749 && info->len < shdr->sh_offset + shdr->sh_size) {
2750 pr_err("Module len %lu truncated\n", info->len);
2754 /* Mark all sections sh_addr with their address in the
2756 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2758 #ifndef CONFIG_MODULE_UNLOAD
2759 /* Don't load .exit sections */
2760 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2761 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2765 /* Track but don't keep modinfo and version sections. */
2766 if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
2767 info->index.vers = 0; /* Pretend no __versions section! */
2769 info->index.vers = find_sec(info, "__versions");
2770 info->index.info = find_sec(info, ".modinfo");
2771 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2772 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2777 * Set up our basic convenience variables (pointers to section headers,
2778 * search for module section index etc), and do some basic section
2781 * Return the temporary module pointer (we'll replace it with the final
2782 * one when we move the module sections around).
2784 static struct module *setup_load_info(struct load_info *info, int flags)
2790 /* Set up the convenience variables */
2791 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2792 info->secstrings = (void *)info->hdr
2793 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2795 err = rewrite_section_headers(info, flags);
2797 return ERR_PTR(err);
2799 /* Find internal symbols and strings. */
2800 for (i = 1; i < info->hdr->e_shnum; i++) {
2801 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2802 info->index.sym = i;
2803 info->index.str = info->sechdrs[i].sh_link;
2804 info->strtab = (char *)info->hdr
2805 + info->sechdrs[info->index.str].sh_offset;
2810 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
2811 if (!info->index.mod) {
2812 pr_warn("No module found in object\n");
2813 return ERR_PTR(-ENOEXEC);
2815 /* This is temporary: point mod into copy of data. */
2816 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2818 if (info->index.sym == 0) {
2819 pr_warn("%s: module has no symbols (stripped?)\n", mod->name);
2820 return ERR_PTR(-ENOEXEC);
2823 info->index.pcpu = find_pcpusec(info);
2825 /* Check module struct version now, before we try to use module. */
2826 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2827 return ERR_PTR(-ENOEXEC);
2832 static int check_modinfo(struct module *mod, struct load_info *info, int flags)
2834 const char *modmagic = get_modinfo(info, "vermagic");
2837 if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2840 /* This is allowed: modprobe --force will invalidate it. */
2842 err = try_to_force_load(mod, "bad vermagic");
2845 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2846 pr_err("%s: version magic '%s' should be '%s'\n",
2847 mod->name, modmagic, vermagic);
2851 if (!get_modinfo(info, "intree"))
2852 add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
2854 if (get_modinfo(info, "staging")) {
2855 add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
2856 pr_warn("%s: module is from the staging directory, the quality "
2857 "is unknown, you have been warned.\n", mod->name);
2860 /* Set up license info based on the info section */
2861 set_license(mod, get_modinfo(info, "license"));
2866 static int find_module_sections(struct module *mod, struct load_info *info)
2868 mod->kp = section_objs(info, "__param",
2869 sizeof(*mod->kp), &mod->num_kp);
2870 mod->syms = section_objs(info, "__ksymtab",
2871 sizeof(*mod->syms), &mod->num_syms);
2872 mod->crcs = section_addr(info, "__kcrctab");
2873 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2874 sizeof(*mod->gpl_syms),
2875 &mod->num_gpl_syms);
2876 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2877 mod->gpl_future_syms = section_objs(info,
2878 "__ksymtab_gpl_future",
2879 sizeof(*mod->gpl_future_syms),
2880 &mod->num_gpl_future_syms);
2881 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
2883 #ifdef CONFIG_UNUSED_SYMBOLS
2884 mod->unused_syms = section_objs(info, "__ksymtab_unused",
2885 sizeof(*mod->unused_syms),
2886 &mod->num_unused_syms);
2887 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2888 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
2889 sizeof(*mod->unused_gpl_syms),
2890 &mod->num_unused_gpl_syms);
2891 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
2893 #ifdef CONFIG_CONSTRUCTORS
2894 mod->ctors = section_objs(info, ".ctors",
2895 sizeof(*mod->ctors), &mod->num_ctors);
2897 mod->ctors = section_objs(info, ".init_array",
2898 sizeof(*mod->ctors), &mod->num_ctors);
2899 else if (find_sec(info, ".init_array")) {
2901 * This shouldn't happen with same compiler and binutils
2902 * building all parts of the module.
2904 pr_warn("%s: has both .ctors and .init_array.\n",
2910 #ifdef CONFIG_TRACEPOINTS
2911 mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2912 sizeof(*mod->tracepoints_ptrs),
2913 &mod->num_tracepoints);
2915 #ifdef HAVE_JUMP_LABEL
2916 mod->jump_entries = section_objs(info, "__jump_table",
2917 sizeof(*mod->jump_entries),
2918 &mod->num_jump_entries);
2920 #ifdef CONFIG_EVENT_TRACING
2921 mod->trace_events = section_objs(info, "_ftrace_events",
2922 sizeof(*mod->trace_events),
2923 &mod->num_trace_events);
2924 mod->trace_enums = section_objs(info, "_ftrace_enum_map",
2925 sizeof(*mod->trace_enums),
2926 &mod->num_trace_enums);
2928 #ifdef CONFIG_TRACING
2929 mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2930 sizeof(*mod->trace_bprintk_fmt_start),
2931 &mod->num_trace_bprintk_fmt);
2933 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2934 /* sechdrs[0].sh_size is always zero */
2935 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
2936 sizeof(*mod->ftrace_callsites),
2937 &mod->num_ftrace_callsites);
2940 mod->extable = section_objs(info, "__ex_table",
2941 sizeof(*mod->extable), &mod->num_exentries);
2943 if (section_addr(info, "__obsparm"))
2944 pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
2946 info->debug = section_objs(info, "__verbose",
2947 sizeof(*info->debug), &info->num_debug);
2952 static int move_module(struct module *mod, struct load_info *info)
2957 /* Do the allocs. */
2958 ptr = module_alloc(mod->core_layout.size);
2960 * The pointer to this block is stored in the module structure
2961 * which is inside the block. Just mark it as not being a
2964 kmemleak_not_leak(ptr);
2968 memset(ptr, 0, mod->core_layout.size);
2969 mod->core_layout.base = ptr;
2971 if (mod->init_layout.size) {
2972 ptr = module_alloc(mod->init_layout.size);
2974 * The pointer to this block is stored in the module structure
2975 * which is inside the block. This block doesn't need to be
2976 * scanned as it contains data and code that will be freed
2977 * after the module is initialized.
2979 kmemleak_ignore(ptr);
2981 module_memfree(mod->core_layout.base);
2984 memset(ptr, 0, mod->init_layout.size);
2985 mod->init_layout.base = ptr;
2987 mod->init_layout.base = NULL;
2989 /* Transfer each section which specifies SHF_ALLOC */
2990 pr_debug("final section addresses:\n");
2991 for (i = 0; i < info->hdr->e_shnum; i++) {
2993 Elf_Shdr *shdr = &info->sechdrs[i];
2995 if (!(shdr->sh_flags & SHF_ALLOC))
2998 if (shdr->sh_entsize & INIT_OFFSET_MASK)
2999 dest = mod->init_layout.base
3000 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
3002 dest = mod->core_layout.base + shdr->sh_entsize;
3004 if (shdr->sh_type != SHT_NOBITS)
3005 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
3006 /* Update sh_addr to point to copy in image. */
3007 shdr->sh_addr = (unsigned long)dest;
3008 pr_debug("\t0x%lx %s\n",
3009 (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
3015 static int check_module_license_and_versions(struct module *mod)
3018 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3019 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3020 * using GPL-only symbols it needs.
3022 if (strcmp(mod->name, "ndiswrapper") == 0)
3023 add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
3025 /* driverloader was caught wrongly pretending to be under GPL */
3026 if (strcmp(mod->name, "driverloader") == 0)
3027 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
3028 LOCKDEP_NOW_UNRELIABLE);
3030 /* lve claims to be GPL but upstream won't provide source */
3031 if (strcmp(mod->name, "lve") == 0)
3032 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
3033 LOCKDEP_NOW_UNRELIABLE);
3035 #ifdef CONFIG_MODVERSIONS
3036 if ((mod->num_syms && !mod->crcs)
3037 || (mod->num_gpl_syms && !mod->gpl_crcs)
3038 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
3039 #ifdef CONFIG_UNUSED_SYMBOLS
3040 || (mod->num_unused_syms && !mod->unused_crcs)
3041 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
3044 return try_to_force_load(mod,
3045 "no versions for exported symbols");
3051 static void flush_module_icache(const struct module *mod)
3053 mm_segment_t old_fs;
3055 /* flush the icache in correct context */
3060 * Flush the instruction cache, since we've played with text.
3061 * Do it before processing of module parameters, so the module
3062 * can provide parameter accessor functions of its own.
3064 if (mod->init_layout.base)
3065 flush_icache_range((unsigned long)mod->init_layout.base,
3066 (unsigned long)mod->init_layout.base
3067 + mod->init_layout.size);
3068 flush_icache_range((unsigned long)mod->core_layout.base,
3069 (unsigned long)mod->core_layout.base + mod->core_layout.size);
3074 int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
3082 static struct module *layout_and_allocate(struct load_info *info, int flags)
3084 /* Module within temporary copy. */
3088 mod = setup_load_info(info, flags);
3092 err = check_modinfo(mod, info, flags);
3094 return ERR_PTR(err);
3096 /* Allow arches to frob section contents and sizes. */
3097 err = module_frob_arch_sections(info->hdr, info->sechdrs,
3098 info->secstrings, mod);
3100 return ERR_PTR(err);
3102 /* We will do a special allocation for per-cpu sections later. */
3103 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
3105 /* Determine total sizes, and put offsets in sh_entsize. For now
3106 this is done generically; there doesn't appear to be any
3107 special cases for the architectures. */
3108 layout_sections(mod, info);
3109 layout_symtab(mod, info);
3111 /* Allocate and move to the final place */
3112 err = move_module(mod, info);
3114 return ERR_PTR(err);
3116 /* Module has been copied to its final place now: return it. */
3117 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
3118 kmemleak_load_module(mod, info);
3122 /* mod is no longer valid after this! */
3123 static void module_deallocate(struct module *mod, struct load_info *info)
3125 percpu_modfree(mod);
3126 module_arch_freeing_init(mod);
3127 module_memfree(mod->init_layout.base);
3128 module_memfree(mod->core_layout.base);
3131 int __weak module_finalize(const Elf_Ehdr *hdr,
3132 const Elf_Shdr *sechdrs,
3138 static int post_relocation(struct module *mod, const struct load_info *info)
3140 /* Sort exception table now relocations are done. */
3141 sort_extable(mod->extable, mod->extable + mod->num_exentries);
3143 /* Copy relocated percpu area over. */
3144 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
3145 info->sechdrs[info->index.pcpu].sh_size);
3147 /* Setup kallsyms-specific fields. */
3148 add_kallsyms(mod, info);
3150 /* Arch-specific module finalizing. */
3151 return module_finalize(info->hdr, info->sechdrs, mod);
3154 /* Is this module of this name done loading? No locks held. */
3155 static bool finished_loading(const char *name)
3161 * The module_mutex should not be a heavily contended lock;
3162 * if we get the occasional sleep here, we'll go an extra iteration
3163 * in the wait_event_interruptible(), which is harmless.
3165 sched_annotate_sleep();
3166 mutex_lock(&module_mutex);
3167 mod = find_module_all(name, strlen(name), true);
3168 ret = !mod || mod->state == MODULE_STATE_LIVE
3169 || mod->state == MODULE_STATE_GOING;
3170 mutex_unlock(&module_mutex);
3175 /* Call module constructors. */
3176 static void do_mod_ctors(struct module *mod)
3178 #ifdef CONFIG_CONSTRUCTORS
3181 for (i = 0; i < mod->num_ctors; i++)
3186 /* For freeing module_init on success, in case kallsyms traversing */
3187 struct mod_initfree {
3188 struct rcu_head rcu;
3192 static void do_free_init(struct rcu_head *head)
3194 struct mod_initfree *m = container_of(head, struct mod_initfree, rcu);
3195 module_memfree(m->module_init);
3200 * This is where the real work happens.
3202 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3203 * helper command 'lx-symbols'.
3205 static noinline int do_init_module(struct module *mod)
3208 struct mod_initfree *freeinit;
3210 freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
3215 freeinit->module_init = mod->init_layout.base;
3218 * We want to find out whether @mod uses async during init. Clear
3219 * PF_USED_ASYNC. async_schedule*() will set it.
3221 current->flags &= ~PF_USED_ASYNC;
3224 /* Start the module */
3225 if (mod->init != NULL)
3226 ret = do_one_initcall(mod->init);
3228 goto fail_free_freeinit;
3231 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3232 "follow 0/-E convention\n"
3233 "%s: loading module anyway...\n",
3234 __func__, mod->name, ret, __func__);
3238 /* Now it's a first class citizen! */
3239 mod->state = MODULE_STATE_LIVE;
3240 blocking_notifier_call_chain(&module_notify_list,
3241 MODULE_STATE_LIVE, mod);
3244 * We need to finish all async code before the module init sequence
3245 * is done. This has potential to deadlock. For example, a newly
3246 * detected block device can trigger request_module() of the
3247 * default iosched from async probing task. Once userland helper
3248 * reaches here, async_synchronize_full() will wait on the async
3249 * task waiting on request_module() and deadlock.
3251 * This deadlock is avoided by perfomring async_synchronize_full()
3252 * iff module init queued any async jobs. This isn't a full
3253 * solution as it will deadlock the same if module loading from
3254 * async jobs nests more than once; however, due to the various
3255 * constraints, this hack seems to be the best option for now.
3256 * Please refer to the following thread for details.
3258 * http://thread.gmane.org/gmane.linux.kernel/1420814
3260 if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC))
3261 async_synchronize_full();
3263 mutex_lock(&module_mutex);
3264 /* Drop initial reference. */
3266 trim_init_extable(mod);
3267 #ifdef CONFIG_KALLSYMS
3268 mod->num_symtab = mod->core_num_syms;
3269 mod->symtab = mod->core_symtab;
3270 mod->strtab = mod->core_strtab;
3272 mod_tree_remove_init(mod);
3273 disable_ro_nx(&mod->init_layout);
3274 module_arch_freeing_init(mod);
3275 mod->init_layout.base = NULL;
3276 mod->init_layout.size = 0;
3277 mod->init_layout.ro_size = 0;
3278 mod->init_layout.text_size = 0;
3280 * We want to free module_init, but be aware that kallsyms may be
3281 * walking this with preempt disabled. In all the failure paths, we
3282 * call synchronize_sched(), but we don't want to slow down the success
3283 * path, so use actual RCU here.
3285 call_rcu_sched(&freeinit->rcu, do_free_init);
3286 mutex_unlock(&module_mutex);
3287 wake_up_all(&module_wq);
3294 /* Try to protect us from buggy refcounters. */
3295 mod->state = MODULE_STATE_GOING;
3296 synchronize_sched();
3298 blocking_notifier_call_chain(&module_notify_list,
3299 MODULE_STATE_GOING, mod);
3300 ftrace_release_mod(mod);
3302 wake_up_all(&module_wq);
3306 static int may_init_module(void)
3308 if (!capable(CAP_SYS_MODULE) || modules_disabled)
3315 * We try to place it in the list now to make sure it's unique before
3316 * we dedicate too many resources. In particular, temporary percpu
3317 * memory exhaustion.
3319 static int add_unformed_module(struct module *mod)
3324 mod->state = MODULE_STATE_UNFORMED;
3327 mutex_lock(&module_mutex);
3328 old = find_module_all(mod->name, strlen(mod->name), true);
3330 if (old->state == MODULE_STATE_COMING
3331 || old->state == MODULE_STATE_UNFORMED) {
3332 /* Wait in case it fails to load. */
3333 mutex_unlock(&module_mutex);
3334 err = wait_event_interruptible(module_wq,
3335 finished_loading(mod->name));
3343 mod_update_bounds(mod);
3344 list_add_rcu(&mod->list, &modules);
3345 mod_tree_insert(mod);
3349 mutex_unlock(&module_mutex);
3354 static int complete_formation(struct module *mod, struct load_info *info)
3358 mutex_lock(&module_mutex);
3360 /* Find duplicate symbols (must be called under lock). */
3361 err = verify_export_symbols(mod);
3365 /* This relies on module_mutex for list integrity. */
3366 module_bug_finalize(info->hdr, info->sechdrs, mod);
3368 /* Set RO and NX regions */
3369 module_enable_ro(mod);
3370 module_enable_nx(mod);
3372 /* Mark state as coming so strong_try_module_get() ignores us,
3373 * but kallsyms etc. can see us. */
3374 mod->state = MODULE_STATE_COMING;
3375 mutex_unlock(&module_mutex);
3377 ftrace_module_enable(mod);
3378 blocking_notifier_call_chain(&module_notify_list,
3379 MODULE_STATE_COMING, mod);
3383 mutex_unlock(&module_mutex);
3387 static int unknown_module_param_cb(char *param, char *val, const char *modname,
3390 struct module *mod = arg;
3393 if (strcmp(param, "async_probe") == 0) {
3394 mod->async_probe_requested = true;
3398 /* Check for magic 'dyndbg' arg */
3399 ret = ddebug_dyndbg_module_param_cb(param, val, modname);
3401 pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
3405 /* Allocate and load the module: note that size of section 0 is always
3406 zero, and we rely on this for optional sections. */
3407 static int load_module(struct load_info *info, const char __user *uargs,
3414 err = module_sig_check(info);
3418 err = elf_header_check(info);
3422 /* Figure out module layout, and allocate all the memory. */
3423 mod = layout_and_allocate(info, flags);
3429 /* Reserve our place in the list. */
3430 err = add_unformed_module(mod);
3434 #ifdef CONFIG_MODULE_SIG
3435 mod->sig_ok = info->sig_ok;
3437 pr_notice_once("%s: module verification failed: signature "
3438 "and/or required key missing - tainting "
3439 "kernel\n", mod->name);
3440 add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
3444 /* To avoid stressing percpu allocator, do this once we're unique. */
3445 err = percpu_modalloc(mod, info);
3449 /* Now module is in final location, initialize linked lists, etc. */
3450 err = module_unload_init(mod);
3454 init_param_lock(mod);
3456 /* Now we've got everything in the final locations, we can
3457 * find optional sections. */
3458 err = find_module_sections(mod, info);
3462 err = check_module_license_and_versions(mod);
3466 /* Set up MODINFO_ATTR fields */
3467 setup_modinfo(mod, info);
3469 /* Fix up syms, so that st_value is a pointer to location. */
3470 err = simplify_symbols(mod, info);
3474 err = apply_relocations(mod, info);
3478 err = post_relocation(mod, info);
3482 flush_module_icache(mod);
3484 /* Now copy in args */
3485 mod->args = strndup_user(uargs, ~0UL >> 1);
3486 if (IS_ERR(mod->args)) {
3487 err = PTR_ERR(mod->args);
3488 goto free_arch_cleanup;
3491 dynamic_debug_setup(info->debug, info->num_debug);
3493 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3494 ftrace_module_init(mod);
3496 /* Finally it's fully formed, ready to start executing. */
3497 err = complete_formation(mod, info);
3499 goto ddebug_cleanup;
3501 /* Module is ready to execute: parsing args may do that. */
3502 after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
3503 -32768, 32767, NULL,
3504 unknown_module_param_cb);
3505 if (IS_ERR(after_dashes)) {
3506 err = PTR_ERR(after_dashes);
3508 } else if (after_dashes) {
3509 pr_warn("%s: parameters '%s' after `--' ignored\n",
3510 mod->name, after_dashes);
3513 /* Link in to syfs. */
3514 err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3518 /* Get rid of temporary copy. */
3522 trace_module_load(mod);
3524 return do_init_module(mod);
3527 /* module_bug_cleanup needs module_mutex protection */
3528 mutex_lock(&module_mutex);
3529 module_bug_cleanup(mod);
3530 mutex_unlock(&module_mutex);
3532 blocking_notifier_call_chain(&module_notify_list,
3533 MODULE_STATE_GOING, mod);
3535 /* we can't deallocate the module until we clear memory protection */
3536 module_disable_ro(mod);
3537 module_disable_nx(mod);
3540 dynamic_debug_remove(info->debug);
3541 synchronize_sched();
3544 module_arch_cleanup(mod);
3548 module_unload_free(mod);
3550 mutex_lock(&module_mutex);
3551 /* Unlink carefully: kallsyms could be walking list. */
3552 list_del_rcu(&mod->list);
3553 mod_tree_remove(mod);
3554 wake_up_all(&module_wq);
3555 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3556 synchronize_sched();
3557 mutex_unlock(&module_mutex);
3560 * Ftrace needs to clean up what it initialized.
3561 * This does nothing if ftrace_module_init() wasn't called,
3562 * but it must be called outside of module_mutex.
3564 ftrace_release_mod(mod);
3565 /* Free lock-classes; relies on the preceding sync_rcu() */
3566 lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
3568 module_deallocate(mod, info);
3574 SYSCALL_DEFINE3(init_module, void __user *, umod,
3575 unsigned long, len, const char __user *, uargs)
3578 struct load_info info = { };
3580 err = may_init_module();
3584 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3587 err = copy_module_from_user(umod, len, &info);
3591 return load_module(&info, uargs, 0);
3594 SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3597 struct load_info info = { };
3599 err = may_init_module();
3603 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3605 if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3606 |MODULE_INIT_IGNORE_VERMAGIC))
3609 err = copy_module_from_fd(fd, &info);
3613 return load_module(&info, uargs, flags);
3616 static inline int within(unsigned long addr, void *start, unsigned long size)
3618 return ((void *)addr >= start && (void *)addr < start + size);
3621 #ifdef CONFIG_KALLSYMS
3623 * This ignores the intensely annoying "mapping symbols" found
3624 * in ARM ELF files: $a, $t and $d.
3626 static inline int is_arm_mapping_symbol(const char *str)
3628 if (str[0] == '.' && str[1] == 'L')
3630 return str[0] == '$' && strchr("axtd", str[1])
3631 && (str[2] == '\0' || str[2] == '.');
3634 static const char *get_ksymbol(struct module *mod,
3636 unsigned long *size,
3637 unsigned long *offset)
3639 unsigned int i, best = 0;
3640 unsigned long nextval;
3642 /* At worse, next value is at end of module */
3643 if (within_module_init(addr, mod))
3644 nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size;
3646 nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size;
3648 /* Scan for closest preceding symbol, and next symbol. (ELF
3649 starts real symbols at 1). */
3650 for (i = 1; i < mod->num_symtab; i++) {
3651 if (mod->symtab[i].st_shndx == SHN_UNDEF)
3654 /* We ignore unnamed symbols: they're uninformative
3655 * and inserted at a whim. */
3656 if (mod->symtab[i].st_value <= addr
3657 && mod->symtab[i].st_value > mod->symtab[best].st_value
3658 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3659 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3661 if (mod->symtab[i].st_value > addr
3662 && mod->symtab[i].st_value < nextval
3663 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3664 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3665 nextval = mod->symtab[i].st_value;
3672 *size = nextval - mod->symtab[best].st_value;
3674 *offset = addr - mod->symtab[best].st_value;
3675 return mod->strtab + mod->symtab[best].st_name;
3678 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3679 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3680 const char *module_address_lookup(unsigned long addr,
3681 unsigned long *size,
3682 unsigned long *offset,
3686 const char *ret = NULL;
3690 mod = __module_address(addr);
3693 *modname = mod->name;
3694 ret = get_ksymbol(mod, addr, size, offset);
3696 /* Make a copy in here where it's safe */
3698 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
3706 int lookup_module_symbol_name(unsigned long addr, char *symname)
3711 list_for_each_entry_rcu(mod, &modules, list) {
3712 if (mod->state == MODULE_STATE_UNFORMED)
3714 if (within_module(addr, mod)) {
3717 sym = get_ksymbol(mod, addr, NULL, NULL);
3720 strlcpy(symname, sym, KSYM_NAME_LEN);
3730 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
3731 unsigned long *offset, char *modname, char *name)
3736 list_for_each_entry_rcu(mod, &modules, list) {
3737 if (mod->state == MODULE_STATE_UNFORMED)
3739 if (within_module(addr, mod)) {
3742 sym = get_ksymbol(mod, addr, size, offset);
3746 strlcpy(modname, mod->name, MODULE_NAME_LEN);
3748 strlcpy(name, sym, KSYM_NAME_LEN);
3758 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
3759 char *name, char *module_name, int *exported)
3764 list_for_each_entry_rcu(mod, &modules, list) {
3765 if (mod->state == MODULE_STATE_UNFORMED)
3767 if (symnum < mod->num_symtab) {
3768 *value = mod->symtab[symnum].st_value;
3769 *type = mod->symtab[symnum].st_info;
3770 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
3772 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
3773 *exported = is_exported(name, *value, mod);
3777 symnum -= mod->num_symtab;
3783 static unsigned long mod_find_symname(struct module *mod, const char *name)
3787 for (i = 0; i < mod->num_symtab; i++)
3788 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
3789 mod->symtab[i].st_info != 'U')
3790 return mod->symtab[i].st_value;
3794 /* Look for this name: can be of form module:name. */
3795 unsigned long module_kallsyms_lookup_name(const char *name)
3799 unsigned long ret = 0;
3801 /* Don't lock: we're in enough trouble already. */
3803 if ((colon = strchr(name, ':')) != NULL) {
3804 if ((mod = find_module_all(name, colon - name, false)) != NULL)
3805 ret = mod_find_symname(mod, colon+1);
3807 list_for_each_entry_rcu(mod, &modules, list) {
3808 if (mod->state == MODULE_STATE_UNFORMED)
3810 if ((ret = mod_find_symname(mod, name)) != 0)
3818 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3819 struct module *, unsigned long),
3826 module_assert_mutex();
3828 list_for_each_entry(mod, &modules, list) {
3829 if (mod->state == MODULE_STATE_UNFORMED)
3831 for (i = 0; i < mod->num_symtab; i++) {
3832 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
3833 mod, mod->symtab[i].st_value);
3840 #endif /* CONFIG_KALLSYMS */
3842 static char *module_flags(struct module *mod, char *buf)
3846 BUG_ON(mod->state == MODULE_STATE_UNFORMED);
3848 mod->state == MODULE_STATE_GOING ||
3849 mod->state == MODULE_STATE_COMING) {
3851 bx += module_flags_taint(mod, buf + bx);
3852 /* Show a - for module-is-being-unloaded */
3853 if (mod->state == MODULE_STATE_GOING)
3855 /* Show a + for module-is-being-loaded */
3856 if (mod->state == MODULE_STATE_COMING)
3865 #ifdef CONFIG_PROC_FS
3866 /* Called by the /proc file system to return a list of modules. */
3867 static void *m_start(struct seq_file *m, loff_t *pos)
3869 mutex_lock(&module_mutex);
3870 return seq_list_start(&modules, *pos);
3873 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3875 return seq_list_next(p, &modules, pos);
3878 static void m_stop(struct seq_file *m, void *p)
3880 mutex_unlock(&module_mutex);
3883 static int m_show(struct seq_file *m, void *p)
3885 struct module *mod = list_entry(p, struct module, list);
3888 /* We always ignore unformed modules. */
3889 if (mod->state == MODULE_STATE_UNFORMED)
3892 seq_printf(m, "%s %u",
3893 mod->name, mod->init_layout.size + mod->core_layout.size);
3894 print_unload_info(m, mod);
3896 /* Informative for users. */
3897 seq_printf(m, " %s",
3898 mod->state == MODULE_STATE_GOING ? "Unloading" :
3899 mod->state == MODULE_STATE_COMING ? "Loading" :
3901 /* Used by oprofile and other similar tools. */
3902 seq_printf(m, " 0x%pK", mod->core_layout.base);
3906 seq_printf(m, " %s", module_flags(mod, buf));
3912 /* Format: modulename size refcount deps address
3914 Where refcount is a number or -, and deps is a comma-separated list
3917 static const struct seq_operations modules_op = {
3924 static int modules_open(struct inode *inode, struct file *file)
3926 return seq_open(file, &modules_op);
3929 static const struct file_operations proc_modules_operations = {
3930 .open = modules_open,
3932 .llseek = seq_lseek,
3933 .release = seq_release,
3936 static int __init proc_modules_init(void)
3938 proc_create("modules", 0, NULL, &proc_modules_operations);
3941 module_init(proc_modules_init);
3944 /* Given an address, look for it in the module exception tables. */
3945 const struct exception_table_entry *search_module_extables(unsigned long addr)
3947 const struct exception_table_entry *e = NULL;
3951 list_for_each_entry_rcu(mod, &modules, list) {
3952 if (mod->state == MODULE_STATE_UNFORMED)
3954 if (mod->num_exentries == 0)
3957 e = search_extable(mod->extable,
3958 mod->extable + mod->num_exentries - 1,
3965 /* Now, if we found one, we are running inside it now, hence
3966 we cannot unload the module, hence no refcnt needed. */
3971 * is_module_address - is this address inside a module?
3972 * @addr: the address to check.
3974 * See is_module_text_address() if you simply want to see if the address
3975 * is code (not data).
3977 bool is_module_address(unsigned long addr)
3982 ret = __module_address(addr) != NULL;
3989 * __module_address - get the module which contains an address.
3990 * @addr: the address.
3992 * Must be called with preempt disabled or module mutex held so that
3993 * module doesn't get freed during this.
3995 struct module *__module_address(unsigned long addr)
3999 if (addr < module_addr_min || addr > module_addr_max)
4002 module_assert_mutex_or_preempt();
4004 mod = mod_find(addr);
4006 BUG_ON(!within_module(addr, mod));
4007 if (mod->state == MODULE_STATE_UNFORMED)
4012 EXPORT_SYMBOL_GPL(__module_address);
4015 * is_module_text_address - is this address inside module code?
4016 * @addr: the address to check.
4018 * See is_module_address() if you simply want to see if the address is
4019 * anywhere in a module. See kernel_text_address() for testing if an
4020 * address corresponds to kernel or module code.
4022 bool is_module_text_address(unsigned long addr)
4027 ret = __module_text_address(addr) != NULL;
4034 * __module_text_address - get the module whose code contains an address.
4035 * @addr: the address.
4037 * Must be called with preempt disabled or module mutex held so that
4038 * module doesn't get freed during this.
4040 struct module *__module_text_address(unsigned long addr)
4042 struct module *mod = __module_address(addr);
4044 /* Make sure it's within the text section. */
4045 if (!within(addr, mod->init_layout.base, mod->init_layout.text_size)
4046 && !within(addr, mod->core_layout.base, mod->core_layout.text_size))
4051 EXPORT_SYMBOL_GPL(__module_text_address);
4053 /* Don't grab lock, we're oopsing. */
4054 void print_modules(void)
4059 printk(KERN_DEFAULT "Modules linked in:");
4060 /* Most callers should already have preempt disabled, but make sure */
4062 list_for_each_entry_rcu(mod, &modules, list) {
4063 if (mod->state == MODULE_STATE_UNFORMED)
4065 pr_cont(" %s%s", mod->name, module_flags(mod, buf));
4068 if (last_unloaded_module[0])
4069 pr_cont(" [last unloaded: %s]", last_unloaded_module);
4073 #ifdef CONFIG_MODVERSIONS
4074 /* Generate the signature for all relevant module structures here.
4075 * If these change, we don't want to try to parse the module. */
4076 void module_layout(struct module *mod,
4077 struct modversion_info *ver,
4078 struct kernel_param *kp,
4079 struct kernel_symbol *ks,
4080 struct tracepoint * const *tp)
4083 EXPORT_SYMBOL(module_layout);