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;
306 #ifdef CONFIG_KALLSYMS
307 unsigned long mod_kallsyms_init_off;
310 unsigned int sym, str, mod, vers, info, pcpu;
314 /* We require a truly strong try_module_get(): 0 means failure due to
315 ongoing or failed initialization etc. */
316 static inline int strong_try_module_get(struct module *mod)
318 BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
319 if (mod && mod->state == MODULE_STATE_COMING)
321 if (try_module_get(mod))
327 static inline void add_taint_module(struct module *mod, unsigned flag,
328 enum lockdep_ok lockdep_ok)
330 add_taint(flag, lockdep_ok);
331 mod->taints |= (1U << flag);
335 * A thread that wants to hold a reference to a module only while it
336 * is running can call this to safely exit. nfsd and lockd use this.
338 void __module_put_and_exit(struct module *mod, long code)
343 EXPORT_SYMBOL(__module_put_and_exit);
345 /* Find a module section: 0 means not found. */
346 static unsigned int find_sec(const struct load_info *info, const char *name)
350 for (i = 1; i < info->hdr->e_shnum; i++) {
351 Elf_Shdr *shdr = &info->sechdrs[i];
352 /* Alloc bit cleared means "ignore it." */
353 if ((shdr->sh_flags & SHF_ALLOC)
354 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
360 /* Find a module section, or NULL. */
361 static void *section_addr(const struct load_info *info, const char *name)
363 /* Section 0 has sh_addr 0. */
364 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
367 /* Find a module section, or NULL. Fill in number of "objects" in section. */
368 static void *section_objs(const struct load_info *info,
373 unsigned int sec = find_sec(info, name);
375 /* Section 0 has sh_addr 0 and sh_size 0. */
376 *num = info->sechdrs[sec].sh_size / object_size;
377 return (void *)info->sechdrs[sec].sh_addr;
380 /* Provided by the linker */
381 extern const struct kernel_symbol __start___ksymtab[];
382 extern const struct kernel_symbol __stop___ksymtab[];
383 extern const struct kernel_symbol __start___ksymtab_gpl[];
384 extern const struct kernel_symbol __stop___ksymtab_gpl[];
385 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
386 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
387 extern const unsigned long __start___kcrctab[];
388 extern const unsigned long __start___kcrctab_gpl[];
389 extern const unsigned long __start___kcrctab_gpl_future[];
390 #ifdef CONFIG_UNUSED_SYMBOLS
391 extern const struct kernel_symbol __start___ksymtab_unused[];
392 extern const struct kernel_symbol __stop___ksymtab_unused[];
393 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
394 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
395 extern const unsigned long __start___kcrctab_unused[];
396 extern const unsigned long __start___kcrctab_unused_gpl[];
399 #ifndef CONFIG_MODVERSIONS
400 #define symversion(base, idx) NULL
402 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
405 static bool each_symbol_in_section(const struct symsearch *arr,
406 unsigned int arrsize,
407 struct module *owner,
408 bool (*fn)(const struct symsearch *syms,
409 struct module *owner,
415 for (j = 0; j < arrsize; j++) {
416 if (fn(&arr[j], owner, data))
423 /* Returns true as soon as fn returns true, otherwise false. */
424 bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
425 struct module *owner,
430 static const struct symsearch arr[] = {
431 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
432 NOT_GPL_ONLY, false },
433 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
434 __start___kcrctab_gpl,
436 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
437 __start___kcrctab_gpl_future,
438 WILL_BE_GPL_ONLY, false },
439 #ifdef CONFIG_UNUSED_SYMBOLS
440 { __start___ksymtab_unused, __stop___ksymtab_unused,
441 __start___kcrctab_unused,
442 NOT_GPL_ONLY, true },
443 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
444 __start___kcrctab_unused_gpl,
449 module_assert_mutex_or_preempt();
451 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
454 list_for_each_entry_rcu(mod, &modules, list) {
455 struct symsearch arr[] = {
456 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
457 NOT_GPL_ONLY, false },
458 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
461 { mod->gpl_future_syms,
462 mod->gpl_future_syms + mod->num_gpl_future_syms,
463 mod->gpl_future_crcs,
464 WILL_BE_GPL_ONLY, false },
465 #ifdef CONFIG_UNUSED_SYMBOLS
467 mod->unused_syms + mod->num_unused_syms,
469 NOT_GPL_ONLY, true },
470 { mod->unused_gpl_syms,
471 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
472 mod->unused_gpl_crcs,
477 if (mod->state == MODULE_STATE_UNFORMED)
480 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
485 EXPORT_SYMBOL_GPL(each_symbol_section);
487 struct find_symbol_arg {
494 struct module *owner;
495 const unsigned long *crc;
496 const struct kernel_symbol *sym;
499 static bool check_symbol(const struct symsearch *syms,
500 struct module *owner,
501 unsigned int symnum, void *data)
503 struct find_symbol_arg *fsa = data;
506 if (syms->licence == GPL_ONLY)
508 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
509 pr_warn("Symbol %s is being used by a non-GPL module, "
510 "which will not be allowed in the future\n",
515 #ifdef CONFIG_UNUSED_SYMBOLS
516 if (syms->unused && fsa->warn) {
517 pr_warn("Symbol %s is marked as UNUSED, however this module is "
518 "using it.\n", fsa->name);
519 pr_warn("This symbol will go away in the future.\n");
520 pr_warn("Please evaluate if this is the right api to use and "
521 "if it really is, submit a report to the linux kernel "
522 "mailing list together with submitting your code for "
528 fsa->crc = symversion(syms->crcs, symnum);
529 fsa->sym = &syms->start[symnum];
533 static int cmp_name(const void *va, const void *vb)
536 const struct kernel_symbol *b;
538 return strcmp(a, b->name);
541 static bool find_symbol_in_section(const struct symsearch *syms,
542 struct module *owner,
545 struct find_symbol_arg *fsa = data;
546 struct kernel_symbol *sym;
548 sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
549 sizeof(struct kernel_symbol), cmp_name);
551 if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
557 /* Find a symbol and return it, along with, (optional) crc and
558 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
559 const struct kernel_symbol *find_symbol(const char *name,
560 struct module **owner,
561 const unsigned long **crc,
565 struct find_symbol_arg fsa;
571 if (each_symbol_section(find_symbol_in_section, &fsa)) {
579 pr_debug("Failed to find symbol %s\n", name);
582 EXPORT_SYMBOL_GPL(find_symbol);
585 * Search for module by name: must hold module_mutex (or preempt disabled
586 * for read-only access).
588 static struct module *find_module_all(const char *name, size_t len,
593 module_assert_mutex_or_preempt();
595 list_for_each_entry(mod, &modules, list) {
596 if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
598 if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
604 struct module *find_module(const char *name)
606 module_assert_mutex();
607 return find_module_all(name, strlen(name), false);
609 EXPORT_SYMBOL_GPL(find_module);
613 static inline void __percpu *mod_percpu(struct module *mod)
618 static int percpu_modalloc(struct module *mod, struct load_info *info)
620 Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
621 unsigned long align = pcpusec->sh_addralign;
623 if (!pcpusec->sh_size)
626 if (align > PAGE_SIZE) {
627 pr_warn("%s: per-cpu alignment %li > %li\n",
628 mod->name, align, PAGE_SIZE);
632 mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
634 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
635 mod->name, (unsigned long)pcpusec->sh_size);
638 mod->percpu_size = pcpusec->sh_size;
642 static void percpu_modfree(struct module *mod)
644 free_percpu(mod->percpu);
647 static unsigned int find_pcpusec(struct load_info *info)
649 return find_sec(info, ".data..percpu");
652 static void percpu_modcopy(struct module *mod,
653 const void *from, unsigned long size)
657 for_each_possible_cpu(cpu)
658 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
662 * is_module_percpu_address - test whether address is from module static percpu
663 * @addr: address to test
665 * Test whether @addr belongs to module static percpu area.
668 * %true if @addr is from module static percpu area
670 bool is_module_percpu_address(unsigned long addr)
677 list_for_each_entry_rcu(mod, &modules, list) {
678 if (mod->state == MODULE_STATE_UNFORMED)
680 if (!mod->percpu_size)
682 for_each_possible_cpu(cpu) {
683 void *start = per_cpu_ptr(mod->percpu, cpu);
685 if ((void *)addr >= start &&
686 (void *)addr < start + mod->percpu_size) {
697 #else /* ... !CONFIG_SMP */
699 static inline void __percpu *mod_percpu(struct module *mod)
703 static int percpu_modalloc(struct module *mod, struct load_info *info)
705 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
706 if (info->sechdrs[info->index.pcpu].sh_size != 0)
710 static inline void percpu_modfree(struct module *mod)
713 static unsigned int find_pcpusec(struct load_info *info)
717 static inline void percpu_modcopy(struct module *mod,
718 const void *from, unsigned long size)
720 /* pcpusec should be 0, and size of that section should be 0. */
723 bool is_module_percpu_address(unsigned long addr)
728 #endif /* CONFIG_SMP */
730 #define MODINFO_ATTR(field) \
731 static void setup_modinfo_##field(struct module *mod, const char *s) \
733 mod->field = kstrdup(s, GFP_KERNEL); \
735 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
736 struct module_kobject *mk, char *buffer) \
738 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
740 static int modinfo_##field##_exists(struct module *mod) \
742 return mod->field != NULL; \
744 static void free_modinfo_##field(struct module *mod) \
749 static struct module_attribute modinfo_##field = { \
750 .attr = { .name = __stringify(field), .mode = 0444 }, \
751 .show = show_modinfo_##field, \
752 .setup = setup_modinfo_##field, \
753 .test = modinfo_##field##_exists, \
754 .free = free_modinfo_##field, \
757 MODINFO_ATTR(version);
758 MODINFO_ATTR(srcversion);
760 static char last_unloaded_module[MODULE_NAME_LEN+1];
762 #ifdef CONFIG_MODULE_UNLOAD
764 EXPORT_TRACEPOINT_SYMBOL(module_get);
766 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
767 #define MODULE_REF_BASE 1
769 /* Init the unload section of the module. */
770 static int module_unload_init(struct module *mod)
773 * Initialize reference counter to MODULE_REF_BASE.
774 * refcnt == 0 means module is going.
776 atomic_set(&mod->refcnt, MODULE_REF_BASE);
778 INIT_LIST_HEAD(&mod->source_list);
779 INIT_LIST_HEAD(&mod->target_list);
781 /* Hold reference count during initialization. */
782 atomic_inc(&mod->refcnt);
787 /* Does a already use b? */
788 static int already_uses(struct module *a, struct module *b)
790 struct module_use *use;
792 list_for_each_entry(use, &b->source_list, source_list) {
793 if (use->source == a) {
794 pr_debug("%s uses %s!\n", a->name, b->name);
798 pr_debug("%s does not use %s!\n", a->name, b->name);
804 * - we add 'a' as a "source", 'b' as a "target" of module use
805 * - the module_use is added to the list of 'b' sources (so
806 * 'b' can walk the list to see who sourced them), and of 'a'
807 * targets (so 'a' can see what modules it targets).
809 static int add_module_usage(struct module *a, struct module *b)
811 struct module_use *use;
813 pr_debug("Allocating new usage for %s.\n", a->name);
814 use = kmalloc(sizeof(*use), GFP_ATOMIC);
816 pr_warn("%s: out of memory loading\n", a->name);
822 list_add(&use->source_list, &b->source_list);
823 list_add(&use->target_list, &a->target_list);
827 /* Module a uses b: caller needs module_mutex() */
828 int ref_module(struct module *a, struct module *b)
832 if (b == NULL || already_uses(a, b))
835 /* If module isn't available, we fail. */
836 err = strong_try_module_get(b);
840 err = add_module_usage(a, b);
847 EXPORT_SYMBOL_GPL(ref_module);
849 /* Clear the unload stuff of the module. */
850 static void module_unload_free(struct module *mod)
852 struct module_use *use, *tmp;
854 mutex_lock(&module_mutex);
855 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
856 struct module *i = use->target;
857 pr_debug("%s unusing %s\n", mod->name, i->name);
859 list_del(&use->source_list);
860 list_del(&use->target_list);
863 mutex_unlock(&module_mutex);
866 #ifdef CONFIG_MODULE_FORCE_UNLOAD
867 static inline int try_force_unload(unsigned int flags)
869 int ret = (flags & O_TRUNC);
871 add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
875 static inline int try_force_unload(unsigned int flags)
879 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
881 /* Try to release refcount of module, 0 means success. */
882 static int try_release_module_ref(struct module *mod)
886 /* Try to decrement refcnt which we set at loading */
887 ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
890 /* Someone can put this right now, recover with checking */
891 ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
896 static int try_stop_module(struct module *mod, int flags, int *forced)
898 /* If it's not unused, quit unless we're forcing. */
899 if (try_release_module_ref(mod) != 0) {
900 *forced = try_force_unload(flags);
905 /* Mark it as dying. */
906 mod->state = MODULE_STATE_GOING;
912 * module_refcount - return the refcount or -1 if unloading
914 * @mod: the module we're checking
917 * -1 if the module is in the process of unloading
918 * otherwise the number of references in the kernel to the module
920 int module_refcount(struct module *mod)
922 return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
924 EXPORT_SYMBOL(module_refcount);
926 /* This exists whether we can unload or not */
927 static void free_module(struct module *mod);
929 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
933 char name[MODULE_NAME_LEN];
936 if (!capable(CAP_SYS_MODULE) || modules_disabled)
939 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
941 name[MODULE_NAME_LEN-1] = '\0';
943 if (mutex_lock_interruptible(&module_mutex) != 0)
946 mod = find_module(name);
952 if (!list_empty(&mod->source_list)) {
953 /* Other modules depend on us: get rid of them first. */
958 /* Doing init or already dying? */
959 if (mod->state != MODULE_STATE_LIVE) {
960 /* FIXME: if (force), slam module count damn the torpedoes */
961 pr_debug("%s already dying\n", mod->name);
966 /* If it has an init func, it must have an exit func to unload */
967 if (mod->init && !mod->exit) {
968 forced = try_force_unload(flags);
970 /* This module can't be removed */
976 /* Stop the machine so refcounts can't move and disable module. */
977 ret = try_stop_module(mod, flags, &forced);
981 mutex_unlock(&module_mutex);
982 /* Final destruction now no one is using it. */
983 if (mod->exit != NULL)
985 blocking_notifier_call_chain(&module_notify_list,
986 MODULE_STATE_GOING, mod);
987 ftrace_release_mod(mod);
989 async_synchronize_full();
991 /* Store the name of the last unloaded module for diagnostic purposes */
992 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
997 mutex_unlock(&module_mutex);
1001 static inline void print_unload_info(struct seq_file *m, struct module *mod)
1003 struct module_use *use;
1004 int printed_something = 0;
1006 seq_printf(m, " %i ", module_refcount(mod));
1009 * Always include a trailing , so userspace can differentiate
1010 * between this and the old multi-field proc format.
1012 list_for_each_entry(use, &mod->source_list, source_list) {
1013 printed_something = 1;
1014 seq_printf(m, "%s,", use->source->name);
1017 if (mod->init != NULL && mod->exit == NULL) {
1018 printed_something = 1;
1019 seq_puts(m, "[permanent],");
1022 if (!printed_something)
1026 void __symbol_put(const char *symbol)
1028 struct module *owner;
1031 if (!find_symbol(symbol, &owner, NULL, true, false))
1036 EXPORT_SYMBOL(__symbol_put);
1038 /* Note this assumes addr is a function, which it currently always is. */
1039 void symbol_put_addr(void *addr)
1041 struct module *modaddr;
1042 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
1044 if (core_kernel_text(a))
1048 * Even though we hold a reference on the module; we still need to
1049 * disable preemption in order to safely traverse the data structure.
1052 modaddr = __module_text_address(a);
1054 module_put(modaddr);
1057 EXPORT_SYMBOL_GPL(symbol_put_addr);
1059 static ssize_t show_refcnt(struct module_attribute *mattr,
1060 struct module_kobject *mk, char *buffer)
1062 return sprintf(buffer, "%i\n", module_refcount(mk->mod));
1065 static struct module_attribute modinfo_refcnt =
1066 __ATTR(refcnt, 0444, show_refcnt, NULL);
1068 void __module_get(struct module *module)
1072 atomic_inc(&module->refcnt);
1073 trace_module_get(module, _RET_IP_);
1077 EXPORT_SYMBOL(__module_get);
1079 bool try_module_get(struct module *module)
1085 /* Note: here, we can fail to get a reference */
1086 if (likely(module_is_live(module) &&
1087 atomic_inc_not_zero(&module->refcnt) != 0))
1088 trace_module_get(module, _RET_IP_);
1096 EXPORT_SYMBOL(try_module_get);
1098 void module_put(struct module *module)
1104 ret = atomic_dec_if_positive(&module->refcnt);
1105 WARN_ON(ret < 0); /* Failed to put refcount */
1106 trace_module_put(module, _RET_IP_);
1110 EXPORT_SYMBOL(module_put);
1112 #else /* !CONFIG_MODULE_UNLOAD */
1113 static inline void print_unload_info(struct seq_file *m, struct module *mod)
1115 /* We don't know the usage count, or what modules are using. */
1116 seq_puts(m, " - -");
1119 static inline void module_unload_free(struct module *mod)
1123 int ref_module(struct module *a, struct module *b)
1125 return strong_try_module_get(b);
1127 EXPORT_SYMBOL_GPL(ref_module);
1129 static inline int module_unload_init(struct module *mod)
1133 #endif /* CONFIG_MODULE_UNLOAD */
1135 static size_t module_flags_taint(struct module *mod, char *buf)
1139 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
1141 if (mod->taints & (1 << TAINT_OOT_MODULE))
1143 if (mod->taints & (1 << TAINT_FORCED_MODULE))
1145 if (mod->taints & (1 << TAINT_CRAP))
1147 if (mod->taints & (1 << TAINT_UNSIGNED_MODULE))
1150 * TAINT_FORCED_RMMOD: could be added.
1151 * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
1157 static ssize_t show_initstate(struct module_attribute *mattr,
1158 struct module_kobject *mk, char *buffer)
1160 const char *state = "unknown";
1162 switch (mk->mod->state) {
1163 case MODULE_STATE_LIVE:
1166 case MODULE_STATE_COMING:
1169 case MODULE_STATE_GOING:
1175 return sprintf(buffer, "%s\n", state);
1178 static struct module_attribute modinfo_initstate =
1179 __ATTR(initstate, 0444, show_initstate, NULL);
1181 static ssize_t store_uevent(struct module_attribute *mattr,
1182 struct module_kobject *mk,
1183 const char *buffer, size_t count)
1185 enum kobject_action action;
1187 if (kobject_action_type(buffer, count, &action) == 0)
1188 kobject_uevent(&mk->kobj, action);
1192 struct module_attribute module_uevent =
1193 __ATTR(uevent, 0200, NULL, store_uevent);
1195 static ssize_t show_coresize(struct module_attribute *mattr,
1196 struct module_kobject *mk, char *buffer)
1198 return sprintf(buffer, "%u\n", mk->mod->core_layout.size);
1201 static struct module_attribute modinfo_coresize =
1202 __ATTR(coresize, 0444, show_coresize, NULL);
1204 static ssize_t show_initsize(struct module_attribute *mattr,
1205 struct module_kobject *mk, char *buffer)
1207 return sprintf(buffer, "%u\n", mk->mod->init_layout.size);
1210 static struct module_attribute modinfo_initsize =
1211 __ATTR(initsize, 0444, show_initsize, NULL);
1213 static ssize_t show_taint(struct module_attribute *mattr,
1214 struct module_kobject *mk, char *buffer)
1218 l = module_flags_taint(mk->mod, buffer);
1223 static struct module_attribute modinfo_taint =
1224 __ATTR(taint, 0444, show_taint, NULL);
1226 static struct module_attribute *modinfo_attrs[] = {
1229 &modinfo_srcversion,
1234 #ifdef CONFIG_MODULE_UNLOAD
1240 static const char vermagic[] = VERMAGIC_STRING;
1242 static int try_to_force_load(struct module *mod, const char *reason)
1244 #ifdef CONFIG_MODULE_FORCE_LOAD
1245 if (!test_taint(TAINT_FORCED_MODULE))
1246 pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
1247 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
1254 #ifdef CONFIG_MODVERSIONS
1255 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
1256 static unsigned long maybe_relocated(unsigned long crc,
1257 const struct module *crc_owner)
1259 #ifdef ARCH_RELOCATES_KCRCTAB
1260 if (crc_owner == NULL)
1261 return crc - (unsigned long)reloc_start;
1266 static int check_version(Elf_Shdr *sechdrs,
1267 unsigned int versindex,
1268 const char *symname,
1270 const unsigned long *crc,
1271 const struct module *crc_owner)
1273 unsigned int i, num_versions;
1274 struct modversion_info *versions;
1276 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1280 /* No versions at all? modprobe --force does this. */
1282 return try_to_force_load(mod, symname) == 0;
1284 versions = (void *) sechdrs[versindex].sh_addr;
1285 num_versions = sechdrs[versindex].sh_size
1286 / sizeof(struct modversion_info);
1288 for (i = 0; i < num_versions; i++) {
1289 if (strcmp(versions[i].name, symname) != 0)
1292 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
1294 pr_debug("Found checksum %lX vs module %lX\n",
1295 maybe_relocated(*crc, crc_owner), versions[i].crc);
1299 pr_warn("%s: no symbol version for %s\n", mod->name, symname);
1303 pr_warn("%s: disagrees about version of symbol %s\n",
1304 mod->name, symname);
1308 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1309 unsigned int versindex,
1312 const unsigned long *crc;
1315 * Since this should be found in kernel (which can't be removed), no
1316 * locking is necessary -- use preempt_disable() to placate lockdep.
1319 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
1320 &crc, true, false)) {
1325 return check_version(sechdrs, versindex,
1326 VMLINUX_SYMBOL_STR(module_layout), mod, crc,
1330 /* First part is kernel version, which we ignore if module has crcs. */
1331 static inline int same_magic(const char *amagic, const char *bmagic,
1335 amagic += strcspn(amagic, " ");
1336 bmagic += strcspn(bmagic, " ");
1338 return strcmp(amagic, bmagic) == 0;
1341 static inline int check_version(Elf_Shdr *sechdrs,
1342 unsigned int versindex,
1343 const char *symname,
1345 const unsigned long *crc,
1346 const struct module *crc_owner)
1351 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1352 unsigned int versindex,
1358 static inline int same_magic(const char *amagic, const char *bmagic,
1361 return strcmp(amagic, bmagic) == 0;
1363 #endif /* CONFIG_MODVERSIONS */
1365 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1366 static const struct kernel_symbol *resolve_symbol(struct module *mod,
1367 const struct load_info *info,
1371 struct module *owner;
1372 const struct kernel_symbol *sym;
1373 const unsigned long *crc;
1377 * The module_mutex should not be a heavily contended lock;
1378 * if we get the occasional sleep here, we'll go an extra iteration
1379 * in the wait_event_interruptible(), which is harmless.
1381 sched_annotate_sleep();
1382 mutex_lock(&module_mutex);
1383 sym = find_symbol(name, &owner, &crc,
1384 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1388 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1390 sym = ERR_PTR(-EINVAL);
1394 err = ref_module(mod, owner);
1401 /* We must make copy under the lock if we failed to get ref. */
1402 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1404 mutex_unlock(&module_mutex);
1408 static const struct kernel_symbol *
1409 resolve_symbol_wait(struct module *mod,
1410 const struct load_info *info,
1413 const struct kernel_symbol *ksym;
1414 char owner[MODULE_NAME_LEN];
1416 if (wait_event_interruptible_timeout(module_wq,
1417 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1418 || PTR_ERR(ksym) != -EBUSY,
1420 pr_warn("%s: gave up waiting for init of module %s.\n",
1427 * /sys/module/foo/sections stuff
1428 * J. Corbet <corbet@lwn.net>
1432 #ifdef CONFIG_KALLSYMS
1433 static inline bool sect_empty(const Elf_Shdr *sect)
1435 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1438 struct module_sect_attr {
1439 struct module_attribute mattr;
1441 unsigned long address;
1444 struct module_sect_attrs {
1445 struct attribute_group grp;
1446 unsigned int nsections;
1447 struct module_sect_attr attrs[0];
1450 static ssize_t module_sect_show(struct module_attribute *mattr,
1451 struct module_kobject *mk, char *buf)
1453 struct module_sect_attr *sattr =
1454 container_of(mattr, struct module_sect_attr, mattr);
1455 return sprintf(buf, "0x%pK\n", (void *)sattr->address);
1458 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1460 unsigned int section;
1462 for (section = 0; section < sect_attrs->nsections; section++)
1463 kfree(sect_attrs->attrs[section].name);
1467 static void add_sect_attrs(struct module *mod, const struct load_info *info)
1469 unsigned int nloaded = 0, i, size[2];
1470 struct module_sect_attrs *sect_attrs;
1471 struct module_sect_attr *sattr;
1472 struct attribute **gattr;
1474 /* Count loaded sections and allocate structures */
1475 for (i = 0; i < info->hdr->e_shnum; i++)
1476 if (!sect_empty(&info->sechdrs[i]))
1478 size[0] = ALIGN(sizeof(*sect_attrs)
1479 + nloaded * sizeof(sect_attrs->attrs[0]),
1480 sizeof(sect_attrs->grp.attrs[0]));
1481 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1482 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1483 if (sect_attrs == NULL)
1486 /* Setup section attributes. */
1487 sect_attrs->grp.name = "sections";
1488 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1490 sect_attrs->nsections = 0;
1491 sattr = §_attrs->attrs[0];
1492 gattr = §_attrs->grp.attrs[0];
1493 for (i = 0; i < info->hdr->e_shnum; i++) {
1494 Elf_Shdr *sec = &info->sechdrs[i];
1495 if (sect_empty(sec))
1497 sattr->address = sec->sh_addr;
1498 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1500 if (sattr->name == NULL)
1502 sect_attrs->nsections++;
1503 sysfs_attr_init(&sattr->mattr.attr);
1504 sattr->mattr.show = module_sect_show;
1505 sattr->mattr.store = NULL;
1506 sattr->mattr.attr.name = sattr->name;
1507 sattr->mattr.attr.mode = S_IRUGO;
1508 *(gattr++) = &(sattr++)->mattr.attr;
1512 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1515 mod->sect_attrs = sect_attrs;
1518 free_sect_attrs(sect_attrs);
1521 static void remove_sect_attrs(struct module *mod)
1523 if (mod->sect_attrs) {
1524 sysfs_remove_group(&mod->mkobj.kobj,
1525 &mod->sect_attrs->grp);
1526 /* We are positive that no one is using any sect attrs
1527 * at this point. Deallocate immediately. */
1528 free_sect_attrs(mod->sect_attrs);
1529 mod->sect_attrs = NULL;
1534 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1537 struct module_notes_attrs {
1538 struct kobject *dir;
1540 struct bin_attribute attrs[0];
1543 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1544 struct bin_attribute *bin_attr,
1545 char *buf, loff_t pos, size_t count)
1548 * The caller checked the pos and count against our size.
1550 memcpy(buf, bin_attr->private + pos, count);
1554 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1557 if (notes_attrs->dir) {
1559 sysfs_remove_bin_file(notes_attrs->dir,
1560 ¬es_attrs->attrs[i]);
1561 kobject_put(notes_attrs->dir);
1566 static void add_notes_attrs(struct module *mod, const struct load_info *info)
1568 unsigned int notes, loaded, i;
1569 struct module_notes_attrs *notes_attrs;
1570 struct bin_attribute *nattr;
1572 /* failed to create section attributes, so can't create notes */
1573 if (!mod->sect_attrs)
1576 /* Count notes sections and allocate structures. */
1578 for (i = 0; i < info->hdr->e_shnum; i++)
1579 if (!sect_empty(&info->sechdrs[i]) &&
1580 (info->sechdrs[i].sh_type == SHT_NOTE))
1586 notes_attrs = kzalloc(sizeof(*notes_attrs)
1587 + notes * sizeof(notes_attrs->attrs[0]),
1589 if (notes_attrs == NULL)
1592 notes_attrs->notes = notes;
1593 nattr = ¬es_attrs->attrs[0];
1594 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1595 if (sect_empty(&info->sechdrs[i]))
1597 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1598 sysfs_bin_attr_init(nattr);
1599 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1600 nattr->attr.mode = S_IRUGO;
1601 nattr->size = info->sechdrs[i].sh_size;
1602 nattr->private = (void *) info->sechdrs[i].sh_addr;
1603 nattr->read = module_notes_read;
1609 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1610 if (!notes_attrs->dir)
1613 for (i = 0; i < notes; ++i)
1614 if (sysfs_create_bin_file(notes_attrs->dir,
1615 ¬es_attrs->attrs[i]))
1618 mod->notes_attrs = notes_attrs;
1622 free_notes_attrs(notes_attrs, i);
1625 static void remove_notes_attrs(struct module *mod)
1627 if (mod->notes_attrs)
1628 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1633 static inline void add_sect_attrs(struct module *mod,
1634 const struct load_info *info)
1638 static inline void remove_sect_attrs(struct module *mod)
1642 static inline void add_notes_attrs(struct module *mod,
1643 const struct load_info *info)
1647 static inline void remove_notes_attrs(struct module *mod)
1650 #endif /* CONFIG_KALLSYMS */
1652 static void add_usage_links(struct module *mod)
1654 #ifdef CONFIG_MODULE_UNLOAD
1655 struct module_use *use;
1658 mutex_lock(&module_mutex);
1659 list_for_each_entry(use, &mod->target_list, target_list) {
1660 nowarn = sysfs_create_link(use->target->holders_dir,
1661 &mod->mkobj.kobj, mod->name);
1663 mutex_unlock(&module_mutex);
1667 static void del_usage_links(struct module *mod)
1669 #ifdef CONFIG_MODULE_UNLOAD
1670 struct module_use *use;
1672 mutex_lock(&module_mutex);
1673 list_for_each_entry(use, &mod->target_list, target_list)
1674 sysfs_remove_link(use->target->holders_dir, mod->name);
1675 mutex_unlock(&module_mutex);
1679 static int module_add_modinfo_attrs(struct module *mod)
1681 struct module_attribute *attr;
1682 struct module_attribute *temp_attr;
1686 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1687 (ARRAY_SIZE(modinfo_attrs) + 1)),
1689 if (!mod->modinfo_attrs)
1692 temp_attr = mod->modinfo_attrs;
1693 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1695 (attr->test && attr->test(mod))) {
1696 memcpy(temp_attr, attr, sizeof(*temp_attr));
1697 sysfs_attr_init(&temp_attr->attr);
1698 error = sysfs_create_file(&mod->mkobj.kobj,
1706 static void module_remove_modinfo_attrs(struct module *mod)
1708 struct module_attribute *attr;
1711 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1712 /* pick a field to test for end of list */
1713 if (!attr->attr.name)
1715 sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
1719 kfree(mod->modinfo_attrs);
1722 static void mod_kobject_put(struct module *mod)
1724 DECLARE_COMPLETION_ONSTACK(c);
1725 mod->mkobj.kobj_completion = &c;
1726 kobject_put(&mod->mkobj.kobj);
1727 wait_for_completion(&c);
1730 static int mod_sysfs_init(struct module *mod)
1733 struct kobject *kobj;
1735 if (!module_sysfs_initialized) {
1736 pr_err("%s: module sysfs not initialized\n", mod->name);
1741 kobj = kset_find_obj(module_kset, mod->name);
1743 pr_err("%s: module is already loaded\n", mod->name);
1749 mod->mkobj.mod = mod;
1751 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1752 mod->mkobj.kobj.kset = module_kset;
1753 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1756 mod_kobject_put(mod);
1758 /* delay uevent until full sysfs population */
1763 static int mod_sysfs_setup(struct module *mod,
1764 const struct load_info *info,
1765 struct kernel_param *kparam,
1766 unsigned int num_params)
1770 err = mod_sysfs_init(mod);
1774 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1775 if (!mod->holders_dir) {
1780 err = module_param_sysfs_setup(mod, kparam, num_params);
1782 goto out_unreg_holders;
1784 err = module_add_modinfo_attrs(mod);
1786 goto out_unreg_param;
1788 add_usage_links(mod);
1789 add_sect_attrs(mod, info);
1790 add_notes_attrs(mod, info);
1792 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1796 module_param_sysfs_remove(mod);
1798 kobject_put(mod->holders_dir);
1800 mod_kobject_put(mod);
1805 static void mod_sysfs_fini(struct module *mod)
1807 remove_notes_attrs(mod);
1808 remove_sect_attrs(mod);
1809 mod_kobject_put(mod);
1812 static void init_param_lock(struct module *mod)
1814 mutex_init(&mod->param_lock);
1816 #else /* !CONFIG_SYSFS */
1818 static int mod_sysfs_setup(struct module *mod,
1819 const struct load_info *info,
1820 struct kernel_param *kparam,
1821 unsigned int num_params)
1826 static void mod_sysfs_fini(struct module *mod)
1830 static void module_remove_modinfo_attrs(struct module *mod)
1834 static void del_usage_links(struct module *mod)
1838 static void init_param_lock(struct module *mod)
1841 #endif /* CONFIG_SYSFS */
1843 static void mod_sysfs_teardown(struct module *mod)
1845 del_usage_links(mod);
1846 module_remove_modinfo_attrs(mod);
1847 module_param_sysfs_remove(mod);
1848 kobject_put(mod->mkobj.drivers_dir);
1849 kobject_put(mod->holders_dir);
1850 mod_sysfs_fini(mod);
1853 #ifdef CONFIG_DEBUG_SET_MODULE_RONX
1855 * LKM RO/NX protection: protect module's text/ro-data
1856 * from modification and any data from execution.
1858 * General layout of module is:
1859 * [text] [read-only-data] [writable data]
1860 * text_size -----^ ^ ^
1861 * ro_size ------------------------| |
1862 * size -------------------------------------------|
1864 * These values are always page-aligned (as is base)
1866 static void frob_text(const struct module_layout *layout,
1867 int (*set_memory)(unsigned long start, int num_pages))
1869 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1870 BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
1871 set_memory((unsigned long)layout->base,
1872 layout->text_size >> PAGE_SHIFT);
1875 static void frob_rodata(const struct module_layout *layout,
1876 int (*set_memory)(unsigned long start, int num_pages))
1878 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1879 BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
1880 BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
1881 set_memory((unsigned long)layout->base + layout->text_size,
1882 (layout->ro_size - layout->text_size) >> PAGE_SHIFT);
1885 static void frob_writable_data(const struct module_layout *layout,
1886 int (*set_memory)(unsigned long start, int num_pages))
1888 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1889 BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
1890 BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1));
1891 set_memory((unsigned long)layout->base + layout->ro_size,
1892 (layout->size - layout->ro_size) >> PAGE_SHIFT);
1895 /* livepatching wants to disable read-only so it can frob module. */
1896 void module_disable_ro(const struct module *mod)
1898 frob_text(&mod->core_layout, set_memory_rw);
1899 frob_rodata(&mod->core_layout, set_memory_rw);
1900 frob_text(&mod->init_layout, set_memory_rw);
1901 frob_rodata(&mod->init_layout, set_memory_rw);
1904 void module_enable_ro(const struct module *mod)
1906 frob_text(&mod->core_layout, set_memory_ro);
1907 frob_rodata(&mod->core_layout, set_memory_ro);
1908 frob_text(&mod->init_layout, set_memory_ro);
1909 frob_rodata(&mod->init_layout, set_memory_ro);
1912 static void module_enable_nx(const struct module *mod)
1914 frob_rodata(&mod->core_layout, set_memory_nx);
1915 frob_writable_data(&mod->core_layout, set_memory_nx);
1916 frob_rodata(&mod->init_layout, set_memory_nx);
1917 frob_writable_data(&mod->init_layout, set_memory_nx);
1920 static void module_disable_nx(const struct module *mod)
1922 frob_rodata(&mod->core_layout, set_memory_x);
1923 frob_writable_data(&mod->core_layout, set_memory_x);
1924 frob_rodata(&mod->init_layout, set_memory_x);
1925 frob_writable_data(&mod->init_layout, set_memory_x);
1928 /* Iterate through all modules and set each module's text as RW */
1929 void set_all_modules_text_rw(void)
1933 mutex_lock(&module_mutex);
1934 list_for_each_entry_rcu(mod, &modules, list) {
1935 if (mod->state == MODULE_STATE_UNFORMED)
1938 frob_text(&mod->core_layout, set_memory_rw);
1939 frob_text(&mod->init_layout, set_memory_rw);
1941 mutex_unlock(&module_mutex);
1944 /* Iterate through all modules and set each module's text as RO */
1945 void set_all_modules_text_ro(void)
1949 mutex_lock(&module_mutex);
1950 list_for_each_entry_rcu(mod, &modules, list) {
1951 if (mod->state == MODULE_STATE_UNFORMED)
1954 frob_text(&mod->core_layout, set_memory_ro);
1955 frob_text(&mod->init_layout, set_memory_ro);
1957 mutex_unlock(&module_mutex);
1960 static void disable_ro_nx(const struct module_layout *layout)
1962 frob_text(layout, set_memory_rw);
1963 frob_rodata(layout, set_memory_rw);
1964 frob_rodata(layout, set_memory_x);
1965 frob_writable_data(layout, set_memory_x);
1969 static void disable_ro_nx(const struct module_layout *layout) { }
1970 static void module_enable_nx(const struct module *mod) { }
1971 static void module_disable_nx(const struct module *mod) { }
1974 void __weak module_memfree(void *module_region)
1976 vfree(module_region);
1979 void __weak module_arch_cleanup(struct module *mod)
1983 void __weak module_arch_freeing_init(struct module *mod)
1987 /* Free a module, remove from lists, etc. */
1988 static void free_module(struct module *mod)
1990 trace_module_free(mod);
1992 mod_sysfs_teardown(mod);
1994 /* We leave it in list to prevent duplicate loads, but make sure
1995 * that noone uses it while it's being deconstructed. */
1996 mutex_lock(&module_mutex);
1997 mod->state = MODULE_STATE_UNFORMED;
1998 mutex_unlock(&module_mutex);
2000 /* Remove dynamic debug info */
2001 ddebug_remove_module(mod->name);
2003 /* Arch-specific cleanup. */
2004 module_arch_cleanup(mod);
2006 /* Module unload stuff */
2007 module_unload_free(mod);
2009 /* Free any allocated parameters. */
2010 destroy_params(mod->kp, mod->num_kp);
2012 /* Now we can delete it from the lists */
2013 mutex_lock(&module_mutex);
2014 /* Unlink carefully: kallsyms could be walking list. */
2015 list_del_rcu(&mod->list);
2016 mod_tree_remove(mod);
2017 /* Remove this module from bug list, this uses list_del_rcu */
2018 module_bug_cleanup(mod);
2019 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2020 synchronize_sched();
2021 mutex_unlock(&module_mutex);
2023 /* This may be empty, but that's OK */
2024 disable_ro_nx(&mod->init_layout);
2025 module_arch_freeing_init(mod);
2026 module_memfree(mod->init_layout.base);
2028 percpu_modfree(mod);
2030 /* Free lock-classes; relies on the preceding sync_rcu(). */
2031 lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
2033 /* Finally, free the core (containing the module structure) */
2034 disable_ro_nx(&mod->core_layout);
2035 module_memfree(mod->core_layout.base);
2038 update_protections(current->mm);
2042 void *__symbol_get(const char *symbol)
2044 struct module *owner;
2045 const struct kernel_symbol *sym;
2048 sym = find_symbol(symbol, &owner, NULL, true, true);
2049 if (sym && strong_try_module_get(owner))
2053 return sym ? (void *)sym->value : NULL;
2055 EXPORT_SYMBOL_GPL(__symbol_get);
2058 * Ensure that an exported symbol [global namespace] does not already exist
2059 * in the kernel or in some other module's exported symbol table.
2061 * You must hold the module_mutex.
2063 static int verify_export_symbols(struct module *mod)
2066 struct module *owner;
2067 const struct kernel_symbol *s;
2069 const struct kernel_symbol *sym;
2072 { mod->syms, mod->num_syms },
2073 { mod->gpl_syms, mod->num_gpl_syms },
2074 { mod->gpl_future_syms, mod->num_gpl_future_syms },
2075 #ifdef CONFIG_UNUSED_SYMBOLS
2076 { mod->unused_syms, mod->num_unused_syms },
2077 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
2081 for (i = 0; i < ARRAY_SIZE(arr); i++) {
2082 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
2083 if (find_symbol(s->name, &owner, NULL, true, false)) {
2084 pr_err("%s: exports duplicate symbol %s"
2086 mod->name, s->name, module_name(owner));
2094 /* Change all symbols so that st_value encodes the pointer directly. */
2095 static int simplify_symbols(struct module *mod, const struct load_info *info)
2097 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2098 Elf_Sym *sym = (void *)symsec->sh_addr;
2099 unsigned long secbase;
2102 const struct kernel_symbol *ksym;
2104 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
2105 const char *name = info->strtab + sym[i].st_name;
2107 switch (sym[i].st_shndx) {
2109 /* Ignore common symbols */
2110 if (!strncmp(name, "__gnu_lto", 9))
2113 /* We compiled with -fno-common. These are not
2114 supposed to happen. */
2115 pr_debug("Common symbol: %s\n", name);
2116 pr_warn("%s: please compile with -fno-common\n",
2122 /* Don't need to do anything */
2123 pr_debug("Absolute symbol: 0x%08lx\n",
2124 (long)sym[i].st_value);
2128 ksym = resolve_symbol_wait(mod, info, name);
2129 /* Ok if resolved. */
2130 if (ksym && !IS_ERR(ksym)) {
2131 sym[i].st_value = ksym->value;
2136 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
2139 pr_warn("%s: Unknown symbol %s (err %li)\n",
2140 mod->name, name, PTR_ERR(ksym));
2141 ret = PTR_ERR(ksym) ?: -ENOENT;
2145 /* Divert to percpu allocation if a percpu var. */
2146 if (sym[i].st_shndx == info->index.pcpu)
2147 secbase = (unsigned long)mod_percpu(mod);
2149 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
2150 sym[i].st_value += secbase;
2158 static int apply_relocations(struct module *mod, const struct load_info *info)
2163 /* Now do relocations. */
2164 for (i = 1; i < info->hdr->e_shnum; i++) {
2165 unsigned int infosec = info->sechdrs[i].sh_info;
2167 /* Not a valid relocation section? */
2168 if (infosec >= info->hdr->e_shnum)
2171 /* Don't bother with non-allocated sections */
2172 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
2175 if (info->sechdrs[i].sh_type == SHT_REL)
2176 err = apply_relocate(info->sechdrs, info->strtab,
2177 info->index.sym, i, mod);
2178 else if (info->sechdrs[i].sh_type == SHT_RELA)
2179 err = apply_relocate_add(info->sechdrs, info->strtab,
2180 info->index.sym, i, mod);
2187 /* Additional bytes needed by arch in front of individual sections */
2188 unsigned int __weak arch_mod_section_prepend(struct module *mod,
2189 unsigned int section)
2191 /* default implementation just returns zero */
2195 /* Update size with this section: return offset. */
2196 static long get_offset(struct module *mod, unsigned int *size,
2197 Elf_Shdr *sechdr, unsigned int section)
2201 *size += arch_mod_section_prepend(mod, section);
2202 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2203 *size = ret + sechdr->sh_size;
2207 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2208 might -- code, read-only data, read-write data, small data. Tally
2209 sizes, and place the offsets into sh_entsize fields: high bit means it
2211 static void layout_sections(struct module *mod, struct load_info *info)
2213 static unsigned long const masks[][2] = {
2214 /* NOTE: all executable code must be the first section
2215 * in this array; otherwise modify the text_size
2216 * finder in the two loops below */
2217 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2218 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
2219 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2220 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2224 for (i = 0; i < info->hdr->e_shnum; i++)
2225 info->sechdrs[i].sh_entsize = ~0UL;
2227 pr_debug("Core section allocation order:\n");
2228 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2229 for (i = 0; i < info->hdr->e_shnum; ++i) {
2230 Elf_Shdr *s = &info->sechdrs[i];
2231 const char *sname = info->secstrings + s->sh_name;
2233 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2234 || (s->sh_flags & masks[m][1])
2235 || s->sh_entsize != ~0UL
2236 || strstarts(sname, ".init"))
2238 s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i);
2239 pr_debug("\t%s\n", sname);
2242 case 0: /* executable */
2243 mod->core_layout.size = debug_align(mod->core_layout.size);
2244 mod->core_layout.text_size = mod->core_layout.size;
2246 case 1: /* RO: text and ro-data */
2247 mod->core_layout.size = debug_align(mod->core_layout.size);
2248 mod->core_layout.ro_size = mod->core_layout.size;
2250 case 3: /* whole core */
2251 mod->core_layout.size = debug_align(mod->core_layout.size);
2256 pr_debug("Init section allocation order:\n");
2257 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2258 for (i = 0; i < info->hdr->e_shnum; ++i) {
2259 Elf_Shdr *s = &info->sechdrs[i];
2260 const char *sname = info->secstrings + s->sh_name;
2262 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2263 || (s->sh_flags & masks[m][1])
2264 || s->sh_entsize != ~0UL
2265 || !strstarts(sname, ".init"))
2267 s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i)
2268 | INIT_OFFSET_MASK);
2269 pr_debug("\t%s\n", sname);
2272 case 0: /* executable */
2273 mod->init_layout.size = debug_align(mod->init_layout.size);
2274 mod->init_layout.text_size = mod->init_layout.size;
2276 case 1: /* RO: text and ro-data */
2277 mod->init_layout.size = debug_align(mod->init_layout.size);
2278 mod->init_layout.ro_size = mod->init_layout.size;
2280 case 3: /* whole init */
2281 mod->init_layout.size = debug_align(mod->init_layout.size);
2287 static void set_license(struct module *mod, const char *license)
2290 license = "unspecified";
2292 if (!license_is_gpl_compatible(license)) {
2293 if (!test_taint(TAINT_PROPRIETARY_MODULE))
2294 pr_warn("%s: module license '%s' taints kernel.\n",
2295 mod->name, license);
2296 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2297 LOCKDEP_NOW_UNRELIABLE);
2301 /* Parse tag=value strings from .modinfo section */
2302 static char *next_string(char *string, unsigned long *secsize)
2304 /* Skip non-zero chars */
2307 if ((*secsize)-- <= 1)
2311 /* Skip any zero padding. */
2312 while (!string[0]) {
2314 if ((*secsize)-- <= 1)
2320 static char *get_modinfo(struct load_info *info, const char *tag)
2323 unsigned int taglen = strlen(tag);
2324 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2325 unsigned long size = infosec->sh_size;
2327 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
2328 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2329 return p + taglen + 1;
2334 static void setup_modinfo(struct module *mod, struct load_info *info)
2336 struct module_attribute *attr;
2339 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2341 attr->setup(mod, get_modinfo(info, attr->attr.name));
2345 static void free_modinfo(struct module *mod)
2347 struct module_attribute *attr;
2350 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2356 #ifdef CONFIG_KALLSYMS
2358 /* lookup symbol in given range of kernel_symbols */
2359 static const struct kernel_symbol *lookup_symbol(const char *name,
2360 const struct kernel_symbol *start,
2361 const struct kernel_symbol *stop)
2363 return bsearch(name, start, stop - start,
2364 sizeof(struct kernel_symbol), cmp_name);
2367 static int is_exported(const char *name, unsigned long value,
2368 const struct module *mod)
2370 const struct kernel_symbol *ks;
2372 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
2374 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
2375 return ks != NULL && ks->value == value;
2379 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
2381 const Elf_Shdr *sechdrs = info->sechdrs;
2383 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2384 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2389 if (sym->st_shndx == SHN_UNDEF)
2391 if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu)
2393 if (sym->st_shndx >= SHN_LORESERVE)
2395 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2397 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2398 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2399 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2401 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2406 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2407 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2412 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2419 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
2420 unsigned int shnum, unsigned int pcpundx)
2422 const Elf_Shdr *sec;
2424 if (src->st_shndx == SHN_UNDEF
2425 || src->st_shndx >= shnum
2429 #ifdef CONFIG_KALLSYMS_ALL
2430 if (src->st_shndx == pcpundx)
2434 sec = sechdrs + src->st_shndx;
2435 if (!(sec->sh_flags & SHF_ALLOC)
2436 #ifndef CONFIG_KALLSYMS_ALL
2437 || !(sec->sh_flags & SHF_EXECINSTR)
2439 || (sec->sh_entsize & INIT_OFFSET_MASK))
2446 * We only allocate and copy the strings needed by the parts of symtab
2447 * we keep. This is simple, but has the effect of making multiple
2448 * copies of duplicates. We could be more sophisticated, see
2449 * linux-kernel thread starting with
2450 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2452 static void layout_symtab(struct module *mod, struct load_info *info)
2454 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2455 Elf_Shdr *strsect = info->sechdrs + info->index.str;
2457 unsigned int i, nsrc, ndst, strtab_size = 0;
2459 /* Put symbol section at end of init part of module. */
2460 symsect->sh_flags |= SHF_ALLOC;
2461 symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect,
2462 info->index.sym) | INIT_OFFSET_MASK;
2463 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
2465 src = (void *)info->hdr + symsect->sh_offset;
2466 nsrc = symsect->sh_size / sizeof(*src);
2468 /* Compute total space required for the core symbols' strtab. */
2469 for (ndst = i = 0; i < nsrc; i++) {
2471 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
2472 info->index.pcpu)) {
2473 strtab_size += strlen(&info->strtab[src[i].st_name])+1;
2478 /* Append room for core symbols at end of core part. */
2479 info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1);
2480 info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym);
2481 mod->core_layout.size += strtab_size;
2482 mod->core_layout.size = debug_align(mod->core_layout.size);
2484 /* Put string table section at end of init part of module. */
2485 strsect->sh_flags |= SHF_ALLOC;
2486 strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect,
2487 info->index.str) | INIT_OFFSET_MASK;
2488 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
2490 /* We'll tack temporary mod_kallsyms on the end. */
2491 mod->init_layout.size = ALIGN(mod->init_layout.size,
2492 __alignof__(struct mod_kallsyms));
2493 info->mod_kallsyms_init_off = mod->init_layout.size;
2494 mod->init_layout.size += sizeof(struct mod_kallsyms);
2495 mod->init_layout.size = debug_align(mod->init_layout.size);
2499 * We use the full symtab and strtab which layout_symtab arranged to
2500 * be appended to the init section. Later we switch to the cut-down
2503 static void add_kallsyms(struct module *mod, const struct load_info *info)
2505 unsigned int i, ndst;
2509 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2511 /* Set up to point into init section. */
2512 mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off;
2514 mod->kallsyms->symtab = (void *)symsec->sh_addr;
2515 mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2516 /* Make sure we get permanent strtab: don't use info->strtab. */
2517 mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2519 /* Set types up while we still have access to sections. */
2520 for (i = 0; i < mod->kallsyms->num_symtab; i++)
2521 mod->kallsyms->symtab[i].st_info
2522 = elf_type(&mod->kallsyms->symtab[i], info);
2524 /* Now populate the cut down core kallsyms for after init. */
2525 mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs;
2526 mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs;
2527 src = mod->kallsyms->symtab;
2528 for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) {
2530 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
2531 info->index.pcpu)) {
2533 dst[ndst++].st_name = s - mod->core_kallsyms.strtab;
2534 s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name],
2538 mod->core_kallsyms.num_symtab = ndst;
2541 static inline void layout_symtab(struct module *mod, struct load_info *info)
2545 static void add_kallsyms(struct module *mod, const struct load_info *info)
2548 #endif /* CONFIG_KALLSYMS */
2550 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2554 #ifdef CONFIG_DYNAMIC_DEBUG
2555 if (ddebug_add_module(debug, num, debug->modname))
2556 pr_err("dynamic debug error adding module: %s\n",
2561 static void dynamic_debug_remove(struct _ddebug *debug)
2564 ddebug_remove_module(debug->modname);
2567 void * __weak module_alloc(unsigned long size)
2569 return vmalloc_exec(size);
2572 #ifdef CONFIG_DEBUG_KMEMLEAK
2573 static void kmemleak_load_module(const struct module *mod,
2574 const struct load_info *info)
2578 /* only scan the sections containing data */
2579 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2581 for (i = 1; i < info->hdr->e_shnum; i++) {
2582 /* Scan all writable sections that's not executable */
2583 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
2584 !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
2585 (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
2588 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2589 info->sechdrs[i].sh_size, GFP_KERNEL);
2593 static inline void kmemleak_load_module(const struct module *mod,
2594 const struct load_info *info)
2599 #ifdef CONFIG_MODULE_SIG
2600 static int module_sig_check(struct load_info *info)
2603 const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2604 const void *mod = info->hdr;
2606 if (info->len > markerlen &&
2607 memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
2608 /* We truncate the module to discard the signature */
2609 info->len -= markerlen;
2610 err = mod_verify_sig(mod, &info->len);
2614 info->sig_ok = true;
2618 /* Not having a signature is only an error if we're strict. */
2619 if (err == -ENOKEY && !sig_enforce)
2624 #else /* !CONFIG_MODULE_SIG */
2625 static int module_sig_check(struct load_info *info)
2629 #endif /* !CONFIG_MODULE_SIG */
2631 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2632 static int elf_header_check(struct load_info *info)
2634 if (info->len < sizeof(*(info->hdr)))
2637 if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2638 || info->hdr->e_type != ET_REL
2639 || !elf_check_arch(info->hdr)
2640 || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2643 if (info->hdr->e_shoff >= info->len
2644 || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2645 info->len - info->hdr->e_shoff))
2651 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2653 static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len)
2656 unsigned long n = min(len, COPY_CHUNK_SIZE);
2658 if (copy_from_user(dst, usrc, n) != 0)
2668 /* Sets info->hdr and info->len. */
2669 static int copy_module_from_user(const void __user *umod, unsigned long len,
2670 struct load_info *info)
2675 if (info->len < sizeof(*(info->hdr)))
2678 err = security_kernel_read_file(NULL, READING_MODULE);
2682 /* Suck in entire file: we'll want most of it. */
2683 info->hdr = __vmalloc(info->len,
2684 GFP_KERNEL | __GFP_HIGHMEM | __GFP_NOWARN, PAGE_KERNEL);
2688 if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
2696 static void free_copy(struct load_info *info)
2701 static int rewrite_section_headers(struct load_info *info, int flags)
2705 /* This should always be true, but let's be sure. */
2706 info->sechdrs[0].sh_addr = 0;
2708 for (i = 1; i < info->hdr->e_shnum; i++) {
2709 Elf_Shdr *shdr = &info->sechdrs[i];
2710 if (shdr->sh_type != SHT_NOBITS
2711 && info->len < shdr->sh_offset + shdr->sh_size) {
2712 pr_err("Module len %lu truncated\n", info->len);
2716 /* Mark all sections sh_addr with their address in the
2718 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2720 #ifndef CONFIG_MODULE_UNLOAD
2721 /* Don't load .exit sections */
2722 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2723 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2727 /* Track but don't keep modinfo and version sections. */
2728 if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
2729 info->index.vers = 0; /* Pretend no __versions section! */
2731 info->index.vers = find_sec(info, "__versions");
2732 info->index.info = find_sec(info, ".modinfo");
2733 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2734 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2739 * Set up our basic convenience variables (pointers to section headers,
2740 * search for module section index etc), and do some basic section
2743 * Return the temporary module pointer (we'll replace it with the final
2744 * one when we move the module sections around).
2746 static struct module *setup_load_info(struct load_info *info, int flags)
2752 /* Set up the convenience variables */
2753 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2754 info->secstrings = (void *)info->hdr
2755 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2757 err = rewrite_section_headers(info, flags);
2759 return ERR_PTR(err);
2761 /* Find internal symbols and strings. */
2762 for (i = 1; i < info->hdr->e_shnum; i++) {
2763 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2764 info->index.sym = i;
2765 info->index.str = info->sechdrs[i].sh_link;
2766 info->strtab = (char *)info->hdr
2767 + info->sechdrs[info->index.str].sh_offset;
2772 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
2773 if (!info->index.mod) {
2774 pr_warn("No module found in object\n");
2775 return ERR_PTR(-ENOEXEC);
2777 /* This is temporary: point mod into copy of data. */
2778 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2780 if (info->index.sym == 0) {
2781 pr_warn("%s: module has no symbols (stripped?)\n", mod->name);
2782 return ERR_PTR(-ENOEXEC);
2785 info->index.pcpu = find_pcpusec(info);
2787 /* Check module struct version now, before we try to use module. */
2788 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2789 return ERR_PTR(-ENOEXEC);
2794 static int check_modinfo(struct module *mod, struct load_info *info, int flags)
2796 const char *modmagic = get_modinfo(info, "vermagic");
2799 if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2802 /* This is allowed: modprobe --force will invalidate it. */
2804 err = try_to_force_load(mod, "bad vermagic");
2807 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2808 pr_err("%s: version magic '%s' should be '%s'\n",
2809 mod->name, modmagic, vermagic);
2813 if (!get_modinfo(info, "intree"))
2814 add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
2816 if (get_modinfo(info, "staging")) {
2817 add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
2818 pr_warn("%s: module is from the staging directory, the quality "
2819 "is unknown, you have been warned.\n", mod->name);
2822 /* Set up license info based on the info section */
2823 set_license(mod, get_modinfo(info, "license"));
2828 static int find_module_sections(struct module *mod, struct load_info *info)
2830 mod->kp = section_objs(info, "__param",
2831 sizeof(*mod->kp), &mod->num_kp);
2832 mod->syms = section_objs(info, "__ksymtab",
2833 sizeof(*mod->syms), &mod->num_syms);
2834 mod->crcs = section_addr(info, "__kcrctab");
2835 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2836 sizeof(*mod->gpl_syms),
2837 &mod->num_gpl_syms);
2838 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2839 mod->gpl_future_syms = section_objs(info,
2840 "__ksymtab_gpl_future",
2841 sizeof(*mod->gpl_future_syms),
2842 &mod->num_gpl_future_syms);
2843 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
2845 #ifdef CONFIG_UNUSED_SYMBOLS
2846 mod->unused_syms = section_objs(info, "__ksymtab_unused",
2847 sizeof(*mod->unused_syms),
2848 &mod->num_unused_syms);
2849 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2850 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
2851 sizeof(*mod->unused_gpl_syms),
2852 &mod->num_unused_gpl_syms);
2853 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
2855 #ifdef CONFIG_CONSTRUCTORS
2856 mod->ctors = section_objs(info, ".ctors",
2857 sizeof(*mod->ctors), &mod->num_ctors);
2859 mod->ctors = section_objs(info, ".init_array",
2860 sizeof(*mod->ctors), &mod->num_ctors);
2861 else if (find_sec(info, ".init_array")) {
2863 * This shouldn't happen with same compiler and binutils
2864 * building all parts of the module.
2866 pr_warn("%s: has both .ctors and .init_array.\n",
2872 #ifdef CONFIG_TRACEPOINTS
2873 mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2874 sizeof(*mod->tracepoints_ptrs),
2875 &mod->num_tracepoints);
2877 #ifdef HAVE_JUMP_LABEL
2878 mod->jump_entries = section_objs(info, "__jump_table",
2879 sizeof(*mod->jump_entries),
2880 &mod->num_jump_entries);
2882 #ifdef CONFIG_EVENT_TRACING
2883 mod->trace_events = section_objs(info, "_ftrace_events",
2884 sizeof(*mod->trace_events),
2885 &mod->num_trace_events);
2886 mod->trace_enums = section_objs(info, "_ftrace_enum_map",
2887 sizeof(*mod->trace_enums),
2888 &mod->num_trace_enums);
2890 #ifdef CONFIG_TRACING
2891 mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2892 sizeof(*mod->trace_bprintk_fmt_start),
2893 &mod->num_trace_bprintk_fmt);
2895 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2896 /* sechdrs[0].sh_size is always zero */
2897 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
2898 sizeof(*mod->ftrace_callsites),
2899 &mod->num_ftrace_callsites);
2902 mod->extable = section_objs(info, "__ex_table",
2903 sizeof(*mod->extable), &mod->num_exentries);
2905 if (section_addr(info, "__obsparm"))
2906 pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
2908 info->debug = section_objs(info, "__verbose",
2909 sizeof(*info->debug), &info->num_debug);
2914 static int move_module(struct module *mod, struct load_info *info)
2919 /* Do the allocs. */
2920 ptr = module_alloc(mod->core_layout.size);
2922 * The pointer to this block is stored in the module structure
2923 * which is inside the block. Just mark it as not being a
2926 kmemleak_not_leak(ptr);
2930 memset(ptr, 0, mod->core_layout.size);
2931 mod->core_layout.base = ptr;
2933 if (mod->init_layout.size) {
2934 ptr = module_alloc(mod->init_layout.size);
2936 * The pointer to this block is stored in the module structure
2937 * which is inside the block. This block doesn't need to be
2938 * scanned as it contains data and code that will be freed
2939 * after the module is initialized.
2941 kmemleak_ignore(ptr);
2943 module_memfree(mod->core_layout.base);
2946 memset(ptr, 0, mod->init_layout.size);
2947 mod->init_layout.base = ptr;
2949 mod->init_layout.base = NULL;
2951 /* Transfer each section which specifies SHF_ALLOC */
2952 pr_debug("final section addresses:\n");
2953 for (i = 0; i < info->hdr->e_shnum; i++) {
2955 Elf_Shdr *shdr = &info->sechdrs[i];
2957 if (!(shdr->sh_flags & SHF_ALLOC))
2960 if (shdr->sh_entsize & INIT_OFFSET_MASK)
2961 dest = mod->init_layout.base
2962 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
2964 dest = mod->core_layout.base + shdr->sh_entsize;
2966 if (shdr->sh_type != SHT_NOBITS)
2967 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2968 /* Update sh_addr to point to copy in image. */
2969 shdr->sh_addr = (unsigned long)dest;
2970 pr_debug("\t0x%lx %s\n",
2971 (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
2977 static int check_module_license_and_versions(struct module *mod)
2980 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2981 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2982 * using GPL-only symbols it needs.
2984 if (strcmp(mod->name, "ndiswrapper") == 0)
2985 add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
2987 /* driverloader was caught wrongly pretending to be under GPL */
2988 if (strcmp(mod->name, "driverloader") == 0)
2989 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2990 LOCKDEP_NOW_UNRELIABLE);
2992 /* lve claims to be GPL but upstream won't provide source */
2993 if (strcmp(mod->name, "lve") == 0)
2994 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2995 LOCKDEP_NOW_UNRELIABLE);
2997 #ifdef CONFIG_MODVERSIONS
2998 if ((mod->num_syms && !mod->crcs)
2999 || (mod->num_gpl_syms && !mod->gpl_crcs)
3000 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
3001 #ifdef CONFIG_UNUSED_SYMBOLS
3002 || (mod->num_unused_syms && !mod->unused_crcs)
3003 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
3006 return try_to_force_load(mod,
3007 "no versions for exported symbols");
3013 static void flush_module_icache(const struct module *mod)
3015 mm_segment_t old_fs;
3017 /* flush the icache in correct context */
3022 * Flush the instruction cache, since we've played with text.
3023 * Do it before processing of module parameters, so the module
3024 * can provide parameter accessor functions of its own.
3026 if (mod->init_layout.base)
3027 flush_icache_range((unsigned long)mod->init_layout.base,
3028 (unsigned long)mod->init_layout.base
3029 + mod->init_layout.size);
3030 flush_icache_range((unsigned long)mod->core_layout.base,
3031 (unsigned long)mod->core_layout.base + mod->core_layout.size);
3036 int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
3044 static struct module *layout_and_allocate(struct load_info *info, int flags)
3046 /* Module within temporary copy. */
3050 mod = setup_load_info(info, flags);
3054 err = check_modinfo(mod, info, flags);
3056 return ERR_PTR(err);
3058 /* Allow arches to frob section contents and sizes. */
3059 err = module_frob_arch_sections(info->hdr, info->sechdrs,
3060 info->secstrings, mod);
3062 return ERR_PTR(err);
3064 /* We will do a special allocation for per-cpu sections later. */
3065 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
3067 /* Determine total sizes, and put offsets in sh_entsize. For now
3068 this is done generically; there doesn't appear to be any
3069 special cases for the architectures. */
3070 layout_sections(mod, info);
3071 layout_symtab(mod, info);
3073 /* Allocate and move to the final place */
3074 err = move_module(mod, info);
3076 return ERR_PTR(err);
3078 /* Module has been copied to its final place now: return it. */
3079 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
3080 kmemleak_load_module(mod, info);
3084 /* mod is no longer valid after this! */
3085 static void module_deallocate(struct module *mod, struct load_info *info)
3087 percpu_modfree(mod);
3088 module_arch_freeing_init(mod);
3089 module_memfree(mod->init_layout.base);
3090 module_memfree(mod->core_layout.base);
3093 int __weak module_finalize(const Elf_Ehdr *hdr,
3094 const Elf_Shdr *sechdrs,
3100 static int post_relocation(struct module *mod, const struct load_info *info)
3102 /* Sort exception table now relocations are done. */
3103 sort_extable(mod->extable, mod->extable + mod->num_exentries);
3105 /* Copy relocated percpu area over. */
3106 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
3107 info->sechdrs[info->index.pcpu].sh_size);
3109 /* Setup kallsyms-specific fields. */
3110 add_kallsyms(mod, info);
3112 /* Arch-specific module finalizing. */
3113 return module_finalize(info->hdr, info->sechdrs, mod);
3116 /* Is this module of this name done loading? No locks held. */
3117 static bool finished_loading(const char *name)
3123 * The module_mutex should not be a heavily contended lock;
3124 * if we get the occasional sleep here, we'll go an extra iteration
3125 * in the wait_event_interruptible(), which is harmless.
3127 sched_annotate_sleep();
3128 mutex_lock(&module_mutex);
3129 mod = find_module_all(name, strlen(name), true);
3130 ret = !mod || mod->state == MODULE_STATE_LIVE
3131 || mod->state == MODULE_STATE_GOING;
3132 mutex_unlock(&module_mutex);
3137 /* Call module constructors. */
3138 static void do_mod_ctors(struct module *mod)
3140 #ifdef CONFIG_CONSTRUCTORS
3143 for (i = 0; i < mod->num_ctors; i++)
3148 /* For freeing module_init on success, in case kallsyms traversing */
3149 struct mod_initfree {
3150 struct rcu_head rcu;
3154 static void do_free_init(struct rcu_head *head)
3156 struct mod_initfree *m = container_of(head, struct mod_initfree, rcu);
3157 module_memfree(m->module_init);
3162 * This is where the real work happens.
3164 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3165 * helper command 'lx-symbols'.
3167 static noinline int do_init_module(struct module *mod)
3170 struct mod_initfree *freeinit;
3172 freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
3177 freeinit->module_init = mod->init_layout.base;
3180 * We want to find out whether @mod uses async during init. Clear
3181 * PF_USED_ASYNC. async_schedule*() will set it.
3183 current->flags &= ~PF_USED_ASYNC;
3186 /* Start the module */
3187 if (mod->init != NULL)
3188 ret = do_one_initcall(mod->init);
3190 goto fail_free_freeinit;
3193 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3194 "follow 0/-E convention\n"
3195 "%s: loading module anyway...\n",
3196 __func__, mod->name, ret, __func__);
3200 /* Now it's a first class citizen! */
3201 mod->state = MODULE_STATE_LIVE;
3202 blocking_notifier_call_chain(&module_notify_list,
3203 MODULE_STATE_LIVE, mod);
3206 * We need to finish all async code before the module init sequence
3207 * is done. This has potential to deadlock. For example, a newly
3208 * detected block device can trigger request_module() of the
3209 * default iosched from async probing task. Once userland helper
3210 * reaches here, async_synchronize_full() will wait on the async
3211 * task waiting on request_module() and deadlock.
3213 * This deadlock is avoided by perfomring async_synchronize_full()
3214 * iff module init queued any async jobs. This isn't a full
3215 * solution as it will deadlock the same if module loading from
3216 * async jobs nests more than once; however, due to the various
3217 * constraints, this hack seems to be the best option for now.
3218 * Please refer to the following thread for details.
3220 * http://thread.gmane.org/gmane.linux.kernel/1420814
3222 if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC))
3223 async_synchronize_full();
3225 mutex_lock(&module_mutex);
3226 /* Drop initial reference. */
3228 trim_init_extable(mod);
3229 #ifdef CONFIG_KALLSYMS
3230 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3231 rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
3233 mod_tree_remove_init(mod);
3234 disable_ro_nx(&mod->init_layout);
3235 module_arch_freeing_init(mod);
3236 mod->init_layout.base = NULL;
3237 mod->init_layout.size = 0;
3238 mod->init_layout.ro_size = 0;
3239 mod->init_layout.text_size = 0;
3241 * We want to free module_init, but be aware that kallsyms may be
3242 * walking this with preempt disabled. In all the failure paths, we
3243 * call synchronize_sched(), but we don't want to slow down the success
3244 * path, so use actual RCU here.
3246 call_rcu_sched(&freeinit->rcu, do_free_init);
3247 mutex_unlock(&module_mutex);
3248 wake_up_all(&module_wq);
3255 /* Try to protect us from buggy refcounters. */
3256 mod->state = MODULE_STATE_GOING;
3257 synchronize_sched();
3259 blocking_notifier_call_chain(&module_notify_list,
3260 MODULE_STATE_GOING, mod);
3261 ftrace_release_mod(mod);
3263 wake_up_all(&module_wq);
3267 static int may_init_module(void)
3269 if (!capable(CAP_SYS_MODULE) || modules_disabled)
3276 * We try to place it in the list now to make sure it's unique before
3277 * we dedicate too many resources. In particular, temporary percpu
3278 * memory exhaustion.
3280 static int add_unformed_module(struct module *mod)
3285 mod->state = MODULE_STATE_UNFORMED;
3288 mutex_lock(&module_mutex);
3289 old = find_module_all(mod->name, strlen(mod->name), true);
3291 if (old->state == MODULE_STATE_COMING
3292 || old->state == MODULE_STATE_UNFORMED) {
3293 /* Wait in case it fails to load. */
3294 mutex_unlock(&module_mutex);
3295 err = wait_event_interruptible(module_wq,
3296 finished_loading(mod->name));
3304 mod_update_bounds(mod);
3305 list_add_rcu(&mod->list, &modules);
3306 mod_tree_insert(mod);
3310 mutex_unlock(&module_mutex);
3315 static int complete_formation(struct module *mod, struct load_info *info)
3319 mutex_lock(&module_mutex);
3321 /* Find duplicate symbols (must be called under lock). */
3322 err = verify_export_symbols(mod);
3326 /* This relies on module_mutex for list integrity. */
3327 module_bug_finalize(info->hdr, info->sechdrs, mod);
3329 /* Set RO and NX regions */
3330 module_enable_ro(mod);
3331 module_enable_nx(mod);
3333 /* Mark state as coming so strong_try_module_get() ignores us,
3334 * but kallsyms etc. can see us. */
3335 mod->state = MODULE_STATE_COMING;
3336 mutex_unlock(&module_mutex);
3338 ftrace_module_enable(mod);
3339 blocking_notifier_call_chain(&module_notify_list,
3340 MODULE_STATE_COMING, mod);
3344 mutex_unlock(&module_mutex);
3348 static int unknown_module_param_cb(char *param, char *val, const char *modname,
3351 struct module *mod = arg;
3354 if (strcmp(param, "async_probe") == 0) {
3355 mod->async_probe_requested = true;
3359 /* Check for magic 'dyndbg' arg */
3360 ret = ddebug_dyndbg_module_param_cb(param, val, modname);
3362 pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
3366 /* Allocate and load the module: note that size of section 0 is always
3367 zero, and we rely on this for optional sections. */
3368 static int load_module(struct load_info *info, const char __user *uargs,
3375 err = module_sig_check(info);
3379 err = elf_header_check(info);
3383 /* Figure out module layout, and allocate all the memory. */
3384 mod = layout_and_allocate(info, flags);
3390 /* Reserve our place in the list. */
3391 err = add_unformed_module(mod);
3395 #ifdef CONFIG_MODULE_SIG
3396 mod->sig_ok = info->sig_ok;
3398 pr_notice_once("%s: module verification failed: signature "
3399 "and/or required key missing - tainting "
3400 "kernel\n", mod->name);
3401 add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
3405 /* To avoid stressing percpu allocator, do this once we're unique. */
3406 err = percpu_modalloc(mod, info);
3410 /* Now module is in final location, initialize linked lists, etc. */
3411 err = module_unload_init(mod);
3415 init_param_lock(mod);
3417 /* Now we've got everything in the final locations, we can
3418 * find optional sections. */
3419 err = find_module_sections(mod, info);
3423 err = check_module_license_and_versions(mod);
3427 /* Set up MODINFO_ATTR fields */
3428 setup_modinfo(mod, info);
3430 /* Fix up syms, so that st_value is a pointer to location. */
3431 err = simplify_symbols(mod, info);
3435 err = apply_relocations(mod, info);
3439 err = post_relocation(mod, info);
3443 flush_module_icache(mod);
3445 /* Now copy in args */
3446 mod->args = strndup_user(uargs, ~0UL >> 1);
3447 if (IS_ERR(mod->args)) {
3448 err = PTR_ERR(mod->args);
3449 goto free_arch_cleanup;
3452 dynamic_debug_setup(info->debug, info->num_debug);
3454 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3455 ftrace_module_init(mod);
3457 /* Finally it's fully formed, ready to start executing. */
3458 err = complete_formation(mod, info);
3460 goto ddebug_cleanup;
3462 /* Module is ready to execute: parsing args may do that. */
3463 after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
3465 unknown_module_param_cb);
3466 if (IS_ERR(after_dashes)) {
3467 err = PTR_ERR(after_dashes);
3469 } else if (after_dashes) {
3470 pr_warn("%s: parameters '%s' after `--' ignored\n",
3471 mod->name, after_dashes);
3474 /* Link in to syfs. */
3475 err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3479 /* Get rid of temporary copy. */
3483 trace_module_load(mod);
3485 return do_init_module(mod);
3488 /* module_bug_cleanup needs module_mutex protection */
3489 mutex_lock(&module_mutex);
3490 module_bug_cleanup(mod);
3491 mutex_unlock(&module_mutex);
3493 blocking_notifier_call_chain(&module_notify_list,
3494 MODULE_STATE_GOING, mod);
3496 /* we can't deallocate the module until we clear memory protection */
3497 module_disable_ro(mod);
3498 module_disable_nx(mod);
3501 dynamic_debug_remove(info->debug);
3502 synchronize_sched();
3505 module_arch_cleanup(mod);
3509 module_unload_free(mod);
3511 mutex_lock(&module_mutex);
3512 /* Unlink carefully: kallsyms could be walking list. */
3513 list_del_rcu(&mod->list);
3514 mod_tree_remove(mod);
3515 wake_up_all(&module_wq);
3516 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3517 synchronize_sched();
3518 mutex_unlock(&module_mutex);
3521 * Ftrace needs to clean up what it initialized.
3522 * This does nothing if ftrace_module_init() wasn't called,
3523 * but it must be called outside of module_mutex.
3525 ftrace_release_mod(mod);
3526 /* Free lock-classes; relies on the preceding sync_rcu() */
3527 lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
3529 module_deallocate(mod, info);
3535 SYSCALL_DEFINE3(init_module, void __user *, umod,
3536 unsigned long, len, const char __user *, uargs)
3539 struct load_info info = { };
3541 err = may_init_module();
3545 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3548 err = copy_module_from_user(umod, len, &info);
3552 return load_module(&info, uargs, 0);
3555 SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3557 struct load_info info = { };
3562 err = may_init_module();
3566 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3568 if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3569 |MODULE_INIT_IGNORE_VERMAGIC))
3572 err = kernel_read_file_from_fd(fd, &hdr, &size, INT_MAX,
3579 return load_module(&info, uargs, flags);
3582 static inline int within(unsigned long addr, void *start, unsigned long size)
3584 return ((void *)addr >= start && (void *)addr < start + size);
3587 #ifdef CONFIG_KALLSYMS
3589 * This ignores the intensely annoying "mapping symbols" found
3590 * in ARM ELF files: $a, $t and $d.
3592 static inline int is_arm_mapping_symbol(const char *str)
3594 if (str[0] == '.' && str[1] == 'L')
3596 return str[0] == '$' && strchr("axtd", str[1])
3597 && (str[2] == '\0' || str[2] == '.');
3600 static const char *symname(struct mod_kallsyms *kallsyms, unsigned int symnum)
3602 return kallsyms->strtab + kallsyms->symtab[symnum].st_name;
3605 static const char *get_ksymbol(struct module *mod,
3607 unsigned long *size,
3608 unsigned long *offset)
3610 unsigned int i, best = 0;
3611 unsigned long nextval;
3612 struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
3614 /* At worse, next value is at end of module */
3615 if (within_module_init(addr, mod))
3616 nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size;
3618 nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size;
3620 /* Scan for closest preceding symbol, and next symbol. (ELF
3621 starts real symbols at 1). */
3622 for (i = 1; i < kallsyms->num_symtab; i++) {
3623 if (kallsyms->symtab[i].st_shndx == SHN_UNDEF)
3626 /* We ignore unnamed symbols: they're uninformative
3627 * and inserted at a whim. */
3628 if (*symname(kallsyms, i) == '\0'
3629 || is_arm_mapping_symbol(symname(kallsyms, i)))
3632 if (kallsyms->symtab[i].st_value <= addr
3633 && kallsyms->symtab[i].st_value > kallsyms->symtab[best].st_value)
3635 if (kallsyms->symtab[i].st_value > addr
3636 && kallsyms->symtab[i].st_value < nextval)
3637 nextval = kallsyms->symtab[i].st_value;
3644 *size = nextval - kallsyms->symtab[best].st_value;
3646 *offset = addr - kallsyms->symtab[best].st_value;
3647 return symname(kallsyms, best);
3650 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3651 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3652 const char *module_address_lookup(unsigned long addr,
3653 unsigned long *size,
3654 unsigned long *offset,
3658 const char *ret = NULL;
3662 mod = __module_address(addr);
3665 *modname = mod->name;
3666 ret = get_ksymbol(mod, addr, size, offset);
3668 /* Make a copy in here where it's safe */
3670 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
3678 int lookup_module_symbol_name(unsigned long addr, char *symname)
3683 list_for_each_entry_rcu(mod, &modules, list) {
3684 if (mod->state == MODULE_STATE_UNFORMED)
3686 if (within_module(addr, mod)) {
3689 sym = get_ksymbol(mod, addr, NULL, NULL);
3692 strlcpy(symname, sym, KSYM_NAME_LEN);
3702 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
3703 unsigned long *offset, char *modname, char *name)
3708 list_for_each_entry_rcu(mod, &modules, list) {
3709 if (mod->state == MODULE_STATE_UNFORMED)
3711 if (within_module(addr, mod)) {
3714 sym = get_ksymbol(mod, addr, size, offset);
3718 strlcpy(modname, mod->name, MODULE_NAME_LEN);
3720 strlcpy(name, sym, KSYM_NAME_LEN);
3730 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
3731 char *name, char *module_name, int *exported)
3736 list_for_each_entry_rcu(mod, &modules, list) {
3737 struct mod_kallsyms *kallsyms;
3739 if (mod->state == MODULE_STATE_UNFORMED)
3741 kallsyms = rcu_dereference_sched(mod->kallsyms);
3742 if (symnum < kallsyms->num_symtab) {
3743 *value = kallsyms->symtab[symnum].st_value;
3744 *type = kallsyms->symtab[symnum].st_info;
3745 strlcpy(name, symname(kallsyms, symnum), KSYM_NAME_LEN);
3746 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
3747 *exported = is_exported(name, *value, mod);
3751 symnum -= kallsyms->num_symtab;
3757 static unsigned long mod_find_symname(struct module *mod, const char *name)
3760 struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
3762 for (i = 0; i < kallsyms->num_symtab; i++)
3763 if (strcmp(name, symname(kallsyms, i)) == 0 &&
3764 kallsyms->symtab[i].st_info != 'U')
3765 return kallsyms->symtab[i].st_value;
3769 /* Look for this name: can be of form module:name. */
3770 unsigned long module_kallsyms_lookup_name(const char *name)
3774 unsigned long ret = 0;
3776 /* Don't lock: we're in enough trouble already. */
3778 if ((colon = strchr(name, ':')) != NULL) {
3779 if ((mod = find_module_all(name, colon - name, false)) != NULL)
3780 ret = mod_find_symname(mod, colon+1);
3782 list_for_each_entry_rcu(mod, &modules, list) {
3783 if (mod->state == MODULE_STATE_UNFORMED)
3785 if ((ret = mod_find_symname(mod, name)) != 0)
3793 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3794 struct module *, unsigned long),
3801 module_assert_mutex();
3803 list_for_each_entry(mod, &modules, list) {
3804 /* We hold module_mutex: no need for rcu_dereference_sched */
3805 struct mod_kallsyms *kallsyms = mod->kallsyms;
3807 if (mod->state == MODULE_STATE_UNFORMED)
3809 for (i = 0; i < kallsyms->num_symtab; i++) {
3810 ret = fn(data, symname(kallsyms, i),
3811 mod, kallsyms->symtab[i].st_value);
3818 #endif /* CONFIG_KALLSYMS */
3820 static char *module_flags(struct module *mod, char *buf)
3824 BUG_ON(mod->state == MODULE_STATE_UNFORMED);
3826 mod->state == MODULE_STATE_GOING ||
3827 mod->state == MODULE_STATE_COMING) {
3829 bx += module_flags_taint(mod, buf + bx);
3830 /* Show a - for module-is-being-unloaded */
3831 if (mod->state == MODULE_STATE_GOING)
3833 /* Show a + for module-is-being-loaded */
3834 if (mod->state == MODULE_STATE_COMING)
3843 #ifdef CONFIG_PROC_FS
3844 /* Called by the /proc file system to return a list of modules. */
3845 static void *m_start(struct seq_file *m, loff_t *pos)
3847 mutex_lock(&module_mutex);
3848 return seq_list_start(&modules, *pos);
3851 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3853 return seq_list_next(p, &modules, pos);
3856 static void m_stop(struct seq_file *m, void *p)
3858 mutex_unlock(&module_mutex);
3861 static int m_show(struct seq_file *m, void *p)
3863 struct module *mod = list_entry(p, struct module, list);
3866 /* We always ignore unformed modules. */
3867 if (mod->state == MODULE_STATE_UNFORMED)
3870 seq_printf(m, "%s %u",
3871 mod->name, mod->init_layout.size + mod->core_layout.size);
3872 print_unload_info(m, mod);
3874 /* Informative for users. */
3875 seq_printf(m, " %s",
3876 mod->state == MODULE_STATE_GOING ? "Unloading" :
3877 mod->state == MODULE_STATE_COMING ? "Loading" :
3879 /* Used by oprofile and other similar tools. */
3880 seq_printf(m, " 0x%pK", mod->core_layout.base);
3884 seq_printf(m, " %s", module_flags(mod, buf));
3890 /* Format: modulename size refcount deps address
3892 Where refcount is a number or -, and deps is a comma-separated list
3895 static const struct seq_operations modules_op = {
3902 static int modules_open(struct inode *inode, struct file *file)
3904 return seq_open(file, &modules_op);
3907 static const struct file_operations proc_modules_operations = {
3908 .open = modules_open,
3910 .llseek = seq_lseek,
3911 .release = seq_release,
3914 static int __init proc_modules_init(void)
3916 proc_create("modules", 0, NULL, &proc_modules_operations);
3919 module_init(proc_modules_init);
3922 /* Given an address, look for it in the module exception tables. */
3923 const struct exception_table_entry *search_module_extables(unsigned long addr)
3925 const struct exception_table_entry *e = NULL;
3929 list_for_each_entry_rcu(mod, &modules, list) {
3930 if (mod->state == MODULE_STATE_UNFORMED)
3932 if (mod->num_exentries == 0)
3935 e = search_extable(mod->extable,
3936 mod->extable + mod->num_exentries - 1,
3943 /* Now, if we found one, we are running inside it now, hence
3944 we cannot unload the module, hence no refcnt needed. */
3949 * is_module_address - is this address inside a module?
3950 * @addr: the address to check.
3952 * See is_module_text_address() if you simply want to see if the address
3953 * is code (not data).
3955 bool is_module_address(unsigned long addr)
3960 ret = __module_address(addr) != NULL;
3967 * __module_address - get the module which contains an address.
3968 * @addr: the address.
3970 * Must be called with preempt disabled or module mutex held so that
3971 * module doesn't get freed during this.
3973 struct module *__module_address(unsigned long addr)
3977 if (addr < module_addr_min || addr > module_addr_max)
3980 module_assert_mutex_or_preempt();
3982 mod = mod_find(addr);
3984 BUG_ON(!within_module(addr, mod));
3985 if (mod->state == MODULE_STATE_UNFORMED)
3990 EXPORT_SYMBOL_GPL(__module_address);
3993 * is_module_text_address - is this address inside module code?
3994 * @addr: the address to check.
3996 * See is_module_address() if you simply want to see if the address is
3997 * anywhere in a module. See kernel_text_address() for testing if an
3998 * address corresponds to kernel or module code.
4000 bool is_module_text_address(unsigned long addr)
4005 ret = __module_text_address(addr) != NULL;
4012 * __module_text_address - get the module whose code contains an address.
4013 * @addr: the address.
4015 * Must be called with preempt disabled or module mutex held so that
4016 * module doesn't get freed during this.
4018 struct module *__module_text_address(unsigned long addr)
4020 struct module *mod = __module_address(addr);
4022 /* Make sure it's within the text section. */
4023 if (!within(addr, mod->init_layout.base, mod->init_layout.text_size)
4024 && !within(addr, mod->core_layout.base, mod->core_layout.text_size))
4029 EXPORT_SYMBOL_GPL(__module_text_address);
4031 /* Don't grab lock, we're oopsing. */
4032 void print_modules(void)
4037 printk(KERN_DEFAULT "Modules linked in:");
4038 /* Most callers should already have preempt disabled, but make sure */
4040 list_for_each_entry_rcu(mod, &modules, list) {
4041 if (mod->state == MODULE_STATE_UNFORMED)
4043 pr_cont(" %s%s", mod->name, module_flags(mod, buf));
4046 if (last_unloaded_module[0])
4047 pr_cont(" [last unloaded: %s]", last_unloaded_module);
4051 #ifdef CONFIG_MODVERSIONS
4052 /* Generate the signature for all relevant module structures here.
4053 * If these change, we don't want to try to parse the module. */
4054 void module_layout(struct module *mod,
4055 struct modversion_info *ver,
4056 struct kernel_param *kp,
4057 struct kernel_symbol *ks,
4058 struct tracepoint * const *tp)
4061 EXPORT_SYMBOL(module_layout);