2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 #include <linux/export.h>
20 #include <linux/moduleloader.h>
21 #include <linux/ftrace_event.h>
22 #include <linux/init.h>
23 #include <linux/kallsyms.h>
24 #include <linux/file.h>
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)
84 * Given BASE and SIZE this macro calculates the number of pages the
85 * memory regions occupies
87 #define MOD_NUMBER_OF_PAGES(BASE, SIZE) (((SIZE) > 0) ? \
88 (PFN_DOWN((unsigned long)(BASE) + (SIZE) - 1) - \
89 PFN_DOWN((unsigned long)BASE) + 1) \
92 /* If this is set, the section belongs in the init part of the module */
93 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
97 * 1) List of modules (also safely readable with preempt_disable),
98 * 2) module_use links,
99 * 3) module_addr_min/module_addr_max.
100 * (delete and add uses RCU list operations). */
101 DEFINE_MUTEX(module_mutex);
102 EXPORT_SYMBOL_GPL(module_mutex);
103 static LIST_HEAD(modules);
104 #ifdef CONFIG_KGDB_KDB
105 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
106 #endif /* CONFIG_KGDB_KDB */
108 #ifdef CONFIG_MODULE_SIG
109 #ifdef CONFIG_MODULE_SIG_FORCE
110 static bool sig_enforce = true;
112 static bool sig_enforce = false;
114 static int param_set_bool_enable_only(const char *val,
115 const struct kernel_param *kp)
119 struct kernel_param dummy_kp = *kp;
121 dummy_kp.arg = &test;
123 err = param_set_bool(val, &dummy_kp);
127 /* Don't let them unset it once it's set! */
128 if (!test && sig_enforce)
136 static const struct kernel_param_ops param_ops_bool_enable_only = {
137 .flags = KERNEL_PARAM_OPS_FL_NOARG,
138 .set = param_set_bool_enable_only,
139 .get = param_get_bool,
141 #define param_check_bool_enable_only param_check_bool
143 module_param(sig_enforce, bool_enable_only, 0644);
144 #endif /* !CONFIG_MODULE_SIG_FORCE */
145 #endif /* CONFIG_MODULE_SIG */
147 /* Block module loading/unloading? */
148 int modules_disabled = 0;
149 core_param(nomodule, modules_disabled, bint, 0);
151 /* Waiting for a module to finish initializing? */
152 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
154 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
156 /* Bounds of module allocation, for speeding __module_address.
157 * Protected by module_mutex. */
158 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
160 int register_module_notifier(struct notifier_block *nb)
162 return blocking_notifier_chain_register(&module_notify_list, nb);
164 EXPORT_SYMBOL(register_module_notifier);
166 int unregister_module_notifier(struct notifier_block *nb)
168 return blocking_notifier_chain_unregister(&module_notify_list, nb);
170 EXPORT_SYMBOL(unregister_module_notifier);
176 char *secstrings, *strtab;
177 unsigned long symoffs, stroffs;
178 struct _ddebug *debug;
179 unsigned int num_debug;
182 unsigned int sym, str, mod, vers, info, pcpu;
186 /* We require a truly strong try_module_get(): 0 means failure due to
187 ongoing or failed initialization etc. */
188 static inline int strong_try_module_get(struct module *mod)
190 BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
191 if (mod && mod->state == MODULE_STATE_COMING)
193 if (try_module_get(mod))
199 static inline void add_taint_module(struct module *mod, unsigned flag,
200 enum lockdep_ok lockdep_ok)
202 add_taint(flag, lockdep_ok);
203 mod->taints |= (1U << flag);
207 * A thread that wants to hold a reference to a module only while it
208 * is running can call this to safely exit. nfsd and lockd use this.
210 void __module_put_and_exit(struct module *mod, long code)
215 EXPORT_SYMBOL(__module_put_and_exit);
217 /* Find a module section: 0 means not found. */
218 static unsigned int find_sec(const struct load_info *info, const char *name)
222 for (i = 1; i < info->hdr->e_shnum; i++) {
223 Elf_Shdr *shdr = &info->sechdrs[i];
224 /* Alloc bit cleared means "ignore it." */
225 if ((shdr->sh_flags & SHF_ALLOC)
226 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
232 /* Find a module section, or NULL. */
233 static void *section_addr(const struct load_info *info, const char *name)
235 /* Section 0 has sh_addr 0. */
236 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
239 /* Find a module section, or NULL. Fill in number of "objects" in section. */
240 static void *section_objs(const struct load_info *info,
245 unsigned int sec = find_sec(info, name);
247 /* Section 0 has sh_addr 0 and sh_size 0. */
248 *num = info->sechdrs[sec].sh_size / object_size;
249 return (void *)info->sechdrs[sec].sh_addr;
252 /* Provided by the linker */
253 extern const struct kernel_symbol __start___ksymtab[];
254 extern const struct kernel_symbol __stop___ksymtab[];
255 extern const struct kernel_symbol __start___ksymtab_gpl[];
256 extern const struct kernel_symbol __stop___ksymtab_gpl[];
257 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
258 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
259 extern const unsigned long __start___kcrctab[];
260 extern const unsigned long __start___kcrctab_gpl[];
261 extern const unsigned long __start___kcrctab_gpl_future[];
262 #ifdef CONFIG_UNUSED_SYMBOLS
263 extern const struct kernel_symbol __start___ksymtab_unused[];
264 extern const struct kernel_symbol __stop___ksymtab_unused[];
265 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
266 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
267 extern const unsigned long __start___kcrctab_unused[];
268 extern const unsigned long __start___kcrctab_unused_gpl[];
271 #ifndef CONFIG_MODVERSIONS
272 #define symversion(base, idx) NULL
274 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
277 static bool each_symbol_in_section(const struct symsearch *arr,
278 unsigned int arrsize,
279 struct module *owner,
280 bool (*fn)(const struct symsearch *syms,
281 struct module *owner,
287 for (j = 0; j < arrsize; j++) {
288 if (fn(&arr[j], owner, data))
295 /* Returns true as soon as fn returns true, otherwise false. */
296 bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
297 struct module *owner,
302 static const struct symsearch arr[] = {
303 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
304 NOT_GPL_ONLY, false },
305 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
306 __start___kcrctab_gpl,
308 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
309 __start___kcrctab_gpl_future,
310 WILL_BE_GPL_ONLY, false },
311 #ifdef CONFIG_UNUSED_SYMBOLS
312 { __start___ksymtab_unused, __stop___ksymtab_unused,
313 __start___kcrctab_unused,
314 NOT_GPL_ONLY, true },
315 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
316 __start___kcrctab_unused_gpl,
321 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
324 list_for_each_entry_rcu(mod, &modules, list) {
325 struct symsearch arr[] = {
326 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
327 NOT_GPL_ONLY, false },
328 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
331 { mod->gpl_future_syms,
332 mod->gpl_future_syms + mod->num_gpl_future_syms,
333 mod->gpl_future_crcs,
334 WILL_BE_GPL_ONLY, false },
335 #ifdef CONFIG_UNUSED_SYMBOLS
337 mod->unused_syms + mod->num_unused_syms,
339 NOT_GPL_ONLY, true },
340 { mod->unused_gpl_syms,
341 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
342 mod->unused_gpl_crcs,
347 if (mod->state == MODULE_STATE_UNFORMED)
350 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
355 EXPORT_SYMBOL_GPL(each_symbol_section);
357 struct find_symbol_arg {
364 struct module *owner;
365 const unsigned long *crc;
366 const struct kernel_symbol *sym;
369 static bool check_symbol(const struct symsearch *syms,
370 struct module *owner,
371 unsigned int symnum, void *data)
373 struct find_symbol_arg *fsa = data;
376 if (syms->licence == GPL_ONLY)
378 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
379 pr_warn("Symbol %s is being used by a non-GPL module, "
380 "which will not be allowed in the future\n",
385 #ifdef CONFIG_UNUSED_SYMBOLS
386 if (syms->unused && fsa->warn) {
387 pr_warn("Symbol %s is marked as UNUSED, however this module is "
388 "using it.\n", fsa->name);
389 pr_warn("This symbol will go away in the future.\n");
390 pr_warn("Please evaluate if this is the right api to use and "
391 "if it really is, submit a report to the linux kernel "
392 "mailing list together with submitting your code for "
398 fsa->crc = symversion(syms->crcs, symnum);
399 fsa->sym = &syms->start[symnum];
403 static int cmp_name(const void *va, const void *vb)
406 const struct kernel_symbol *b;
408 return strcmp(a, b->name);
411 static bool find_symbol_in_section(const struct symsearch *syms,
412 struct module *owner,
415 struct find_symbol_arg *fsa = data;
416 struct kernel_symbol *sym;
418 sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
419 sizeof(struct kernel_symbol), cmp_name);
421 if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
427 /* Find a symbol and return it, along with, (optional) crc and
428 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
429 const struct kernel_symbol *find_symbol(const char *name,
430 struct module **owner,
431 const unsigned long **crc,
435 struct find_symbol_arg fsa;
441 if (each_symbol_section(find_symbol_in_section, &fsa)) {
449 pr_debug("Failed to find symbol %s\n", name);
452 EXPORT_SYMBOL_GPL(find_symbol);
454 /* Search for module by name: must hold module_mutex. */
455 static struct module *find_module_all(const char *name, size_t len,
460 list_for_each_entry(mod, &modules, list) {
461 if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
463 if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
469 struct module *find_module(const char *name)
471 return find_module_all(name, strlen(name), false);
473 EXPORT_SYMBOL_GPL(find_module);
477 static inline void __percpu *mod_percpu(struct module *mod)
482 static int percpu_modalloc(struct module *mod, struct load_info *info)
484 Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
485 unsigned long align = pcpusec->sh_addralign;
487 if (!pcpusec->sh_size)
490 if (align > PAGE_SIZE) {
491 pr_warn("%s: per-cpu alignment %li > %li\n",
492 mod->name, align, PAGE_SIZE);
496 mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
498 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
499 mod->name, (unsigned long)pcpusec->sh_size);
502 mod->percpu_size = pcpusec->sh_size;
506 static void percpu_modfree(struct module *mod)
508 free_percpu(mod->percpu);
511 static unsigned int find_pcpusec(struct load_info *info)
513 return find_sec(info, ".data..percpu");
516 static void percpu_modcopy(struct module *mod,
517 const void *from, unsigned long size)
521 for_each_possible_cpu(cpu)
522 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
526 * is_module_percpu_address - test whether address is from module static percpu
527 * @addr: address to test
529 * Test whether @addr belongs to module static percpu area.
532 * %true if @addr is from module static percpu area
534 bool is_module_percpu_address(unsigned long addr)
541 list_for_each_entry_rcu(mod, &modules, list) {
542 if (mod->state == MODULE_STATE_UNFORMED)
544 if (!mod->percpu_size)
546 for_each_possible_cpu(cpu) {
547 void *start = per_cpu_ptr(mod->percpu, cpu);
549 if ((void *)addr >= start &&
550 (void *)addr < start + mod->percpu_size) {
561 #else /* ... !CONFIG_SMP */
563 static inline void __percpu *mod_percpu(struct module *mod)
567 static int percpu_modalloc(struct module *mod, struct load_info *info)
569 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
570 if (info->sechdrs[info->index.pcpu].sh_size != 0)
574 static inline void percpu_modfree(struct module *mod)
577 static unsigned int find_pcpusec(struct load_info *info)
581 static inline void percpu_modcopy(struct module *mod,
582 const void *from, unsigned long size)
584 /* pcpusec should be 0, and size of that section should be 0. */
587 bool is_module_percpu_address(unsigned long addr)
592 #endif /* CONFIG_SMP */
594 #define MODINFO_ATTR(field) \
595 static void setup_modinfo_##field(struct module *mod, const char *s) \
597 mod->field = kstrdup(s, GFP_KERNEL); \
599 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
600 struct module_kobject *mk, char *buffer) \
602 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
604 static int modinfo_##field##_exists(struct module *mod) \
606 return mod->field != NULL; \
608 static void free_modinfo_##field(struct module *mod) \
613 static struct module_attribute modinfo_##field = { \
614 .attr = { .name = __stringify(field), .mode = 0444 }, \
615 .show = show_modinfo_##field, \
616 .setup = setup_modinfo_##field, \
617 .test = modinfo_##field##_exists, \
618 .free = free_modinfo_##field, \
621 MODINFO_ATTR(version);
622 MODINFO_ATTR(srcversion);
624 static char last_unloaded_module[MODULE_NAME_LEN+1];
626 #ifdef CONFIG_MODULE_UNLOAD
628 EXPORT_TRACEPOINT_SYMBOL(module_get);
630 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
631 #define MODULE_REF_BASE 1
633 /* Init the unload section of the module. */
634 static int module_unload_init(struct module *mod)
637 * Initialize reference counter to MODULE_REF_BASE.
638 * refcnt == 0 means module is going.
640 atomic_set(&mod->refcnt, MODULE_REF_BASE);
642 INIT_LIST_HEAD(&mod->source_list);
643 INIT_LIST_HEAD(&mod->target_list);
645 /* Hold reference count during initialization. */
646 atomic_inc(&mod->refcnt);
651 /* Does a already use b? */
652 static int already_uses(struct module *a, struct module *b)
654 struct module_use *use;
656 list_for_each_entry(use, &b->source_list, source_list) {
657 if (use->source == a) {
658 pr_debug("%s uses %s!\n", a->name, b->name);
662 pr_debug("%s does not use %s!\n", a->name, b->name);
668 * - we add 'a' as a "source", 'b' as a "target" of module use
669 * - the module_use is added to the list of 'b' sources (so
670 * 'b' can walk the list to see who sourced them), and of 'a'
671 * targets (so 'a' can see what modules it targets).
673 static int add_module_usage(struct module *a, struct module *b)
675 struct module_use *use;
677 pr_debug("Allocating new usage for %s.\n", a->name);
678 use = kmalloc(sizeof(*use), GFP_ATOMIC);
680 pr_warn("%s: out of memory loading\n", a->name);
686 list_add(&use->source_list, &b->source_list);
687 list_add(&use->target_list, &a->target_list);
691 /* Module a uses b: caller needs module_mutex() */
692 int ref_module(struct module *a, struct module *b)
696 if (b == NULL || already_uses(a, b))
699 /* If module isn't available, we fail. */
700 err = strong_try_module_get(b);
704 err = add_module_usage(a, b);
711 EXPORT_SYMBOL_GPL(ref_module);
713 /* Clear the unload stuff of the module. */
714 static void module_unload_free(struct module *mod)
716 struct module_use *use, *tmp;
718 mutex_lock(&module_mutex);
719 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
720 struct module *i = use->target;
721 pr_debug("%s unusing %s\n", mod->name, i->name);
723 list_del(&use->source_list);
724 list_del(&use->target_list);
727 mutex_unlock(&module_mutex);
730 #ifdef CONFIG_MODULE_FORCE_UNLOAD
731 static inline int try_force_unload(unsigned int flags)
733 int ret = (flags & O_TRUNC);
735 add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
739 static inline int try_force_unload(unsigned int flags)
743 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
745 /* Try to release refcount of module, 0 means success. */
746 static int try_release_module_ref(struct module *mod)
750 /* Try to decrement refcnt which we set at loading */
751 ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
754 /* Someone can put this right now, recover with checking */
755 ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
760 static int try_stop_module(struct module *mod, int flags, int *forced)
762 /* If it's not unused, quit unless we're forcing. */
763 if (try_release_module_ref(mod) != 0) {
764 *forced = try_force_unload(flags);
769 /* Mark it as dying. */
770 mod->state = MODULE_STATE_GOING;
776 * module_refcount - return the refcount or -1 if unloading
778 * @mod: the module we're checking
781 * -1 if the module is in the process of unloading
782 * otherwise the number of references in the kernel to the module
784 int module_refcount(struct module *mod)
786 return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
788 EXPORT_SYMBOL(module_refcount);
790 /* This exists whether we can unload or not */
791 static void free_module(struct module *mod);
793 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
797 char name[MODULE_NAME_LEN];
800 if (!capable(CAP_SYS_MODULE) || modules_disabled)
803 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
805 name[MODULE_NAME_LEN-1] = '\0';
807 if (mutex_lock_interruptible(&module_mutex) != 0)
810 mod = find_module(name);
816 if (!list_empty(&mod->source_list)) {
817 /* Other modules depend on us: get rid of them first. */
822 /* Doing init or already dying? */
823 if (mod->state != MODULE_STATE_LIVE) {
824 /* FIXME: if (force), slam module count damn the torpedoes */
825 pr_debug("%s already dying\n", mod->name);
830 /* If it has an init func, it must have an exit func to unload */
831 if (mod->init && !mod->exit) {
832 forced = try_force_unload(flags);
834 /* This module can't be removed */
840 /* Stop the machine so refcounts can't move and disable module. */
841 ret = try_stop_module(mod, flags, &forced);
845 mutex_unlock(&module_mutex);
846 /* Final destruction now no one is using it. */
847 if (mod->exit != NULL)
849 blocking_notifier_call_chain(&module_notify_list,
850 MODULE_STATE_GOING, mod);
851 async_synchronize_full();
853 /* Store the name of the last unloaded module for diagnostic purposes */
854 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
859 mutex_unlock(&module_mutex);
863 static inline void print_unload_info(struct seq_file *m, struct module *mod)
865 struct module_use *use;
866 int printed_something = 0;
868 seq_printf(m, " %i ", module_refcount(mod));
871 * Always include a trailing , so userspace can differentiate
872 * between this and the old multi-field proc format.
874 list_for_each_entry(use, &mod->source_list, source_list) {
875 printed_something = 1;
876 seq_printf(m, "%s,", use->source->name);
879 if (mod->init != NULL && mod->exit == NULL) {
880 printed_something = 1;
881 seq_puts(m, "[permanent],");
884 if (!printed_something)
888 void __symbol_put(const char *symbol)
890 struct module *owner;
893 if (!find_symbol(symbol, &owner, NULL, true, false))
898 EXPORT_SYMBOL(__symbol_put);
900 /* Note this assumes addr is a function, which it currently always is. */
901 void symbol_put_addr(void *addr)
903 struct module *modaddr;
904 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
906 if (core_kernel_text(a))
909 /* module_text_address is safe here: we're supposed to have reference
910 * to module from symbol_get, so it can't go away. */
911 modaddr = __module_text_address(a);
915 EXPORT_SYMBOL_GPL(symbol_put_addr);
917 static ssize_t show_refcnt(struct module_attribute *mattr,
918 struct module_kobject *mk, char *buffer)
920 return sprintf(buffer, "%i\n", module_refcount(mk->mod));
923 static struct module_attribute modinfo_refcnt =
924 __ATTR(refcnt, 0444, show_refcnt, NULL);
926 void __module_get(struct module *module)
930 atomic_inc(&module->refcnt);
931 trace_module_get(module, _RET_IP_);
935 EXPORT_SYMBOL(__module_get);
937 bool try_module_get(struct module *module)
943 /* Note: here, we can fail to get a reference */
944 if (likely(module_is_live(module) &&
945 atomic_inc_not_zero(&module->refcnt) != 0))
946 trace_module_get(module, _RET_IP_);
954 EXPORT_SYMBOL(try_module_get);
956 void module_put(struct module *module)
962 ret = atomic_dec_if_positive(&module->refcnt);
963 WARN_ON(ret < 0); /* Failed to put refcount */
964 trace_module_put(module, _RET_IP_);
968 EXPORT_SYMBOL(module_put);
970 #else /* !CONFIG_MODULE_UNLOAD */
971 static inline void print_unload_info(struct seq_file *m, struct module *mod)
973 /* We don't know the usage count, or what modules are using. */
977 static inline void module_unload_free(struct module *mod)
981 int ref_module(struct module *a, struct module *b)
983 return strong_try_module_get(b);
985 EXPORT_SYMBOL_GPL(ref_module);
987 static inline int module_unload_init(struct module *mod)
991 #endif /* CONFIG_MODULE_UNLOAD */
993 static size_t module_flags_taint(struct module *mod, char *buf)
997 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
999 if (mod->taints & (1 << TAINT_OOT_MODULE))
1001 if (mod->taints & (1 << TAINT_FORCED_MODULE))
1003 if (mod->taints & (1 << TAINT_CRAP))
1005 if (mod->taints & (1 << TAINT_UNSIGNED_MODULE))
1008 * TAINT_FORCED_RMMOD: could be added.
1009 * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
1015 static ssize_t show_initstate(struct module_attribute *mattr,
1016 struct module_kobject *mk, char *buffer)
1018 const char *state = "unknown";
1020 switch (mk->mod->state) {
1021 case MODULE_STATE_LIVE:
1024 case MODULE_STATE_COMING:
1027 case MODULE_STATE_GOING:
1033 return sprintf(buffer, "%s\n", state);
1036 static struct module_attribute modinfo_initstate =
1037 __ATTR(initstate, 0444, show_initstate, NULL);
1039 static ssize_t store_uevent(struct module_attribute *mattr,
1040 struct module_kobject *mk,
1041 const char *buffer, size_t count)
1043 enum kobject_action action;
1045 if (kobject_action_type(buffer, count, &action) == 0)
1046 kobject_uevent(&mk->kobj, action);
1050 struct module_attribute module_uevent =
1051 __ATTR(uevent, 0200, NULL, store_uevent);
1053 static ssize_t show_coresize(struct module_attribute *mattr,
1054 struct module_kobject *mk, char *buffer)
1056 return sprintf(buffer, "%u\n", mk->mod->core_size);
1059 static struct module_attribute modinfo_coresize =
1060 __ATTR(coresize, 0444, show_coresize, NULL);
1062 static ssize_t show_initsize(struct module_attribute *mattr,
1063 struct module_kobject *mk, char *buffer)
1065 return sprintf(buffer, "%u\n", mk->mod->init_size);
1068 static struct module_attribute modinfo_initsize =
1069 __ATTR(initsize, 0444, show_initsize, NULL);
1071 static ssize_t show_taint(struct module_attribute *mattr,
1072 struct module_kobject *mk, char *buffer)
1076 l = module_flags_taint(mk->mod, buffer);
1081 static struct module_attribute modinfo_taint =
1082 __ATTR(taint, 0444, show_taint, NULL);
1084 static struct module_attribute *modinfo_attrs[] = {
1087 &modinfo_srcversion,
1092 #ifdef CONFIG_MODULE_UNLOAD
1098 static const char vermagic[] = VERMAGIC_STRING;
1100 static int try_to_force_load(struct module *mod, const char *reason)
1102 #ifdef CONFIG_MODULE_FORCE_LOAD
1103 if (!test_taint(TAINT_FORCED_MODULE))
1104 pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
1105 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
1112 #ifdef CONFIG_MODVERSIONS
1113 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
1114 static unsigned long maybe_relocated(unsigned long crc,
1115 const struct module *crc_owner)
1117 #ifdef ARCH_RELOCATES_KCRCTAB
1118 if (crc_owner == NULL)
1119 return crc - (unsigned long)reloc_start;
1124 static int check_version(Elf_Shdr *sechdrs,
1125 unsigned int versindex,
1126 const char *symname,
1128 const unsigned long *crc,
1129 const struct module *crc_owner)
1131 unsigned int i, num_versions;
1132 struct modversion_info *versions;
1134 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1138 /* No versions at all? modprobe --force does this. */
1140 return try_to_force_load(mod, symname) == 0;
1142 versions = (void *) sechdrs[versindex].sh_addr;
1143 num_versions = sechdrs[versindex].sh_size
1144 / sizeof(struct modversion_info);
1146 for (i = 0; i < num_versions; i++) {
1147 if (strcmp(versions[i].name, symname) != 0)
1150 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
1152 pr_debug("Found checksum %lX vs module %lX\n",
1153 maybe_relocated(*crc, crc_owner), versions[i].crc);
1157 pr_warn("%s: no symbol version for %s\n", mod->name, symname);
1161 pr_warn("%s: disagrees about version of symbol %s\n",
1162 mod->name, symname);
1166 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1167 unsigned int versindex,
1170 const unsigned long *crc;
1173 * Since this should be found in kernel (which can't be removed), no
1174 * locking is necessary -- use preempt_disable() to placate lockdep.
1177 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
1178 &crc, true, false)) {
1183 return check_version(sechdrs, versindex,
1184 VMLINUX_SYMBOL_STR(module_layout), mod, crc,
1188 /* First part is kernel version, which we ignore if module has crcs. */
1189 static inline int same_magic(const char *amagic, const char *bmagic,
1193 amagic += strcspn(amagic, " ");
1194 bmagic += strcspn(bmagic, " ");
1196 return strcmp(amagic, bmagic) == 0;
1199 static inline int check_version(Elf_Shdr *sechdrs,
1200 unsigned int versindex,
1201 const char *symname,
1203 const unsigned long *crc,
1204 const struct module *crc_owner)
1209 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1210 unsigned int versindex,
1216 static inline int same_magic(const char *amagic, const char *bmagic,
1219 return strcmp(amagic, bmagic) == 0;
1221 #endif /* CONFIG_MODVERSIONS */
1223 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1224 static const struct kernel_symbol *resolve_symbol(struct module *mod,
1225 const struct load_info *info,
1229 struct module *owner;
1230 const struct kernel_symbol *sym;
1231 const unsigned long *crc;
1235 * The module_mutex should not be a heavily contended lock;
1236 * if we get the occasional sleep here, we'll go an extra iteration
1237 * in the wait_event_interruptible(), which is harmless.
1239 sched_annotate_sleep();
1240 mutex_lock(&module_mutex);
1241 sym = find_symbol(name, &owner, &crc,
1242 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1246 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1248 sym = ERR_PTR(-EINVAL);
1252 err = ref_module(mod, owner);
1259 /* We must make copy under the lock if we failed to get ref. */
1260 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1262 mutex_unlock(&module_mutex);
1266 static const struct kernel_symbol *
1267 resolve_symbol_wait(struct module *mod,
1268 const struct load_info *info,
1271 const struct kernel_symbol *ksym;
1272 char owner[MODULE_NAME_LEN];
1274 if (wait_event_interruptible_timeout(module_wq,
1275 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1276 || PTR_ERR(ksym) != -EBUSY,
1278 pr_warn("%s: gave up waiting for init of module %s.\n",
1285 * /sys/module/foo/sections stuff
1286 * J. Corbet <corbet@lwn.net>
1290 #ifdef CONFIG_KALLSYMS
1291 static inline bool sect_empty(const Elf_Shdr *sect)
1293 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1296 struct module_sect_attr {
1297 struct module_attribute mattr;
1299 unsigned long address;
1302 struct module_sect_attrs {
1303 struct attribute_group grp;
1304 unsigned int nsections;
1305 struct module_sect_attr attrs[0];
1308 static ssize_t module_sect_show(struct module_attribute *mattr,
1309 struct module_kobject *mk, char *buf)
1311 struct module_sect_attr *sattr =
1312 container_of(mattr, struct module_sect_attr, mattr);
1313 return sprintf(buf, "0x%pK\n", (void *)sattr->address);
1316 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1318 unsigned int section;
1320 for (section = 0; section < sect_attrs->nsections; section++)
1321 kfree(sect_attrs->attrs[section].name);
1325 static void add_sect_attrs(struct module *mod, const struct load_info *info)
1327 unsigned int nloaded = 0, i, size[2];
1328 struct module_sect_attrs *sect_attrs;
1329 struct module_sect_attr *sattr;
1330 struct attribute **gattr;
1332 /* Count loaded sections and allocate structures */
1333 for (i = 0; i < info->hdr->e_shnum; i++)
1334 if (!sect_empty(&info->sechdrs[i]))
1336 size[0] = ALIGN(sizeof(*sect_attrs)
1337 + nloaded * sizeof(sect_attrs->attrs[0]),
1338 sizeof(sect_attrs->grp.attrs[0]));
1339 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1340 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1341 if (sect_attrs == NULL)
1344 /* Setup section attributes. */
1345 sect_attrs->grp.name = "sections";
1346 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1348 sect_attrs->nsections = 0;
1349 sattr = §_attrs->attrs[0];
1350 gattr = §_attrs->grp.attrs[0];
1351 for (i = 0; i < info->hdr->e_shnum; i++) {
1352 Elf_Shdr *sec = &info->sechdrs[i];
1353 if (sect_empty(sec))
1355 sattr->address = sec->sh_addr;
1356 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1358 if (sattr->name == NULL)
1360 sect_attrs->nsections++;
1361 sysfs_attr_init(&sattr->mattr.attr);
1362 sattr->mattr.show = module_sect_show;
1363 sattr->mattr.store = NULL;
1364 sattr->mattr.attr.name = sattr->name;
1365 sattr->mattr.attr.mode = S_IRUGO;
1366 *(gattr++) = &(sattr++)->mattr.attr;
1370 if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp))
1373 mod->sect_attrs = sect_attrs;
1376 free_sect_attrs(sect_attrs);
1379 static void remove_sect_attrs(struct module *mod)
1381 if (mod->sect_attrs) {
1382 sysfs_remove_group(&mod->mkobj.kobj,
1383 &mod->sect_attrs->grp);
1384 /* We are positive that no one is using any sect attrs
1385 * at this point. Deallocate immediately. */
1386 free_sect_attrs(mod->sect_attrs);
1387 mod->sect_attrs = NULL;
1392 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1395 struct module_notes_attrs {
1396 struct kobject *dir;
1398 struct bin_attribute attrs[0];
1401 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1402 struct bin_attribute *bin_attr,
1403 char *buf, loff_t pos, size_t count)
1406 * The caller checked the pos and count against our size.
1408 memcpy(buf, bin_attr->private + pos, count);
1412 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1415 if (notes_attrs->dir) {
1417 sysfs_remove_bin_file(notes_attrs->dir,
1418 ¬es_attrs->attrs[i]);
1419 kobject_put(notes_attrs->dir);
1424 static void add_notes_attrs(struct module *mod, const struct load_info *info)
1426 unsigned int notes, loaded, i;
1427 struct module_notes_attrs *notes_attrs;
1428 struct bin_attribute *nattr;
1430 /* failed to create section attributes, so can't create notes */
1431 if (!mod->sect_attrs)
1434 /* Count notes sections and allocate structures. */
1436 for (i = 0; i < info->hdr->e_shnum; i++)
1437 if (!sect_empty(&info->sechdrs[i]) &&
1438 (info->sechdrs[i].sh_type == SHT_NOTE))
1444 notes_attrs = kzalloc(sizeof(*notes_attrs)
1445 + notes * sizeof(notes_attrs->attrs[0]),
1447 if (notes_attrs == NULL)
1450 notes_attrs->notes = notes;
1451 nattr = ¬es_attrs->attrs[0];
1452 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1453 if (sect_empty(&info->sechdrs[i]))
1455 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1456 sysfs_bin_attr_init(nattr);
1457 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1458 nattr->attr.mode = S_IRUGO;
1459 nattr->size = info->sechdrs[i].sh_size;
1460 nattr->private = (void *) info->sechdrs[i].sh_addr;
1461 nattr->read = module_notes_read;
1467 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1468 if (!notes_attrs->dir)
1471 for (i = 0; i < notes; ++i)
1472 if (sysfs_create_bin_file(notes_attrs->dir,
1473 ¬es_attrs->attrs[i]))
1476 mod->notes_attrs = notes_attrs;
1480 free_notes_attrs(notes_attrs, i);
1483 static void remove_notes_attrs(struct module *mod)
1485 if (mod->notes_attrs)
1486 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1491 static inline void add_sect_attrs(struct module *mod,
1492 const struct load_info *info)
1496 static inline void remove_sect_attrs(struct module *mod)
1500 static inline void add_notes_attrs(struct module *mod,
1501 const struct load_info *info)
1505 static inline void remove_notes_attrs(struct module *mod)
1508 #endif /* CONFIG_KALLSYMS */
1510 static void add_usage_links(struct module *mod)
1512 #ifdef CONFIG_MODULE_UNLOAD
1513 struct module_use *use;
1516 mutex_lock(&module_mutex);
1517 list_for_each_entry(use, &mod->target_list, target_list) {
1518 nowarn = sysfs_create_link(use->target->holders_dir,
1519 &mod->mkobj.kobj, mod->name);
1521 mutex_unlock(&module_mutex);
1525 static void del_usage_links(struct module *mod)
1527 #ifdef CONFIG_MODULE_UNLOAD
1528 struct module_use *use;
1530 mutex_lock(&module_mutex);
1531 list_for_each_entry(use, &mod->target_list, target_list)
1532 sysfs_remove_link(use->target->holders_dir, mod->name);
1533 mutex_unlock(&module_mutex);
1537 static int module_add_modinfo_attrs(struct module *mod)
1539 struct module_attribute *attr;
1540 struct module_attribute *temp_attr;
1544 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1545 (ARRAY_SIZE(modinfo_attrs) + 1)),
1547 if (!mod->modinfo_attrs)
1550 temp_attr = mod->modinfo_attrs;
1551 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1553 (attr->test && attr->test(mod))) {
1554 memcpy(temp_attr, attr, sizeof(*temp_attr));
1555 sysfs_attr_init(&temp_attr->attr);
1556 error = sysfs_create_file(&mod->mkobj.kobj,
1564 static void module_remove_modinfo_attrs(struct module *mod)
1566 struct module_attribute *attr;
1569 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1570 /* pick a field to test for end of list */
1571 if (!attr->attr.name)
1573 sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
1577 kfree(mod->modinfo_attrs);
1580 static void mod_kobject_put(struct module *mod)
1582 DECLARE_COMPLETION_ONSTACK(c);
1583 mod->mkobj.kobj_completion = &c;
1584 kobject_put(&mod->mkobj.kobj);
1585 wait_for_completion(&c);
1588 static int mod_sysfs_init(struct module *mod)
1591 struct kobject *kobj;
1593 if (!module_sysfs_initialized) {
1594 pr_err("%s: module sysfs not initialized\n", mod->name);
1599 kobj = kset_find_obj(module_kset, mod->name);
1601 pr_err("%s: module is already loaded\n", mod->name);
1607 mod->mkobj.mod = mod;
1609 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1610 mod->mkobj.kobj.kset = module_kset;
1611 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1614 mod_kobject_put(mod);
1616 /* delay uevent until full sysfs population */
1621 static int mod_sysfs_setup(struct module *mod,
1622 const struct load_info *info,
1623 struct kernel_param *kparam,
1624 unsigned int num_params)
1628 err = mod_sysfs_init(mod);
1632 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1633 if (!mod->holders_dir) {
1638 err = module_param_sysfs_setup(mod, kparam, num_params);
1640 goto out_unreg_holders;
1642 err = module_add_modinfo_attrs(mod);
1644 goto out_unreg_param;
1646 add_usage_links(mod);
1647 add_sect_attrs(mod, info);
1648 add_notes_attrs(mod, info);
1650 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1654 module_param_sysfs_remove(mod);
1656 kobject_put(mod->holders_dir);
1658 mod_kobject_put(mod);
1663 static void mod_sysfs_fini(struct module *mod)
1665 remove_notes_attrs(mod);
1666 remove_sect_attrs(mod);
1667 mod_kobject_put(mod);
1670 #else /* !CONFIG_SYSFS */
1672 static int mod_sysfs_setup(struct module *mod,
1673 const struct load_info *info,
1674 struct kernel_param *kparam,
1675 unsigned int num_params)
1680 static void mod_sysfs_fini(struct module *mod)
1684 static void module_remove_modinfo_attrs(struct module *mod)
1688 static void del_usage_links(struct module *mod)
1692 #endif /* CONFIG_SYSFS */
1694 static void mod_sysfs_teardown(struct module *mod)
1696 del_usage_links(mod);
1697 module_remove_modinfo_attrs(mod);
1698 module_param_sysfs_remove(mod);
1699 kobject_put(mod->mkobj.drivers_dir);
1700 kobject_put(mod->holders_dir);
1701 mod_sysfs_fini(mod);
1704 #ifdef CONFIG_DEBUG_SET_MODULE_RONX
1706 * LKM RO/NX protection: protect module's text/ro-data
1707 * from modification and any data from execution.
1709 void set_page_attributes(void *start, void *end, int (*set)(unsigned long start, int num_pages))
1711 unsigned long begin_pfn = PFN_DOWN((unsigned long)start);
1712 unsigned long end_pfn = PFN_DOWN((unsigned long)end);
1714 if (end_pfn > begin_pfn)
1715 set(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1718 static void set_section_ro_nx(void *base,
1719 unsigned long text_size,
1720 unsigned long ro_size,
1721 unsigned long total_size)
1723 /* begin and end PFNs of the current subsection */
1724 unsigned long begin_pfn;
1725 unsigned long end_pfn;
1728 * Set RO for module text and RO-data:
1729 * - Always protect first page.
1730 * - Do not protect last partial page.
1733 set_page_attributes(base, base + ro_size, set_memory_ro);
1736 * Set NX permissions for module data:
1737 * - Do not protect first partial page.
1738 * - Always protect last page.
1740 if (total_size > text_size) {
1741 begin_pfn = PFN_UP((unsigned long)base + text_size);
1742 end_pfn = PFN_UP((unsigned long)base + total_size);
1743 if (end_pfn > begin_pfn)
1744 set_memory_nx(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1748 static void unset_module_core_ro_nx(struct module *mod)
1750 set_page_attributes(mod->module_core + mod->core_text_size,
1751 mod->module_core + mod->core_size,
1753 set_page_attributes(mod->module_core,
1754 mod->module_core + mod->core_ro_size,
1758 static void unset_module_init_ro_nx(struct module *mod)
1760 set_page_attributes(mod->module_init + mod->init_text_size,
1761 mod->module_init + mod->init_size,
1763 set_page_attributes(mod->module_init,
1764 mod->module_init + mod->init_ro_size,
1768 /* Iterate through all modules and set each module's text as RW */
1769 void set_all_modules_text_rw(void)
1773 mutex_lock(&module_mutex);
1774 list_for_each_entry_rcu(mod, &modules, list) {
1775 if (mod->state == MODULE_STATE_UNFORMED)
1777 if ((mod->module_core) && (mod->core_text_size)) {
1778 set_page_attributes(mod->module_core,
1779 mod->module_core + mod->core_text_size,
1782 if ((mod->module_init) && (mod->init_text_size)) {
1783 set_page_attributes(mod->module_init,
1784 mod->module_init + mod->init_text_size,
1788 mutex_unlock(&module_mutex);
1791 /* Iterate through all modules and set each module's text as RO */
1792 void set_all_modules_text_ro(void)
1796 mutex_lock(&module_mutex);
1797 list_for_each_entry_rcu(mod, &modules, list) {
1798 if (mod->state == MODULE_STATE_UNFORMED)
1800 if ((mod->module_core) && (mod->core_text_size)) {
1801 set_page_attributes(mod->module_core,
1802 mod->module_core + mod->core_text_size,
1805 if ((mod->module_init) && (mod->init_text_size)) {
1806 set_page_attributes(mod->module_init,
1807 mod->module_init + mod->init_text_size,
1811 mutex_unlock(&module_mutex);
1814 static inline void set_section_ro_nx(void *base, unsigned long text_size, unsigned long ro_size, unsigned long total_size) { }
1815 static void unset_module_core_ro_nx(struct module *mod) { }
1816 static void unset_module_init_ro_nx(struct module *mod) { }
1819 void __weak module_memfree(void *module_region)
1821 vfree(module_region);
1824 void __weak module_arch_cleanup(struct module *mod)
1828 void __weak module_arch_freeing_init(struct module *mod)
1832 /* Free a module, remove from lists, etc. */
1833 static void free_module(struct module *mod)
1835 trace_module_free(mod);
1837 mod_sysfs_teardown(mod);
1839 /* We leave it in list to prevent duplicate loads, but make sure
1840 * that noone uses it while it's being deconstructed. */
1841 mutex_lock(&module_mutex);
1842 mod->state = MODULE_STATE_UNFORMED;
1843 mutex_unlock(&module_mutex);
1845 /* Remove dynamic debug info */
1846 ddebug_remove_module(mod->name);
1848 /* Arch-specific cleanup. */
1849 module_arch_cleanup(mod);
1851 /* Module unload stuff */
1852 module_unload_free(mod);
1854 /* Free any allocated parameters. */
1855 destroy_params(mod->kp, mod->num_kp);
1857 /* Now we can delete it from the lists */
1858 mutex_lock(&module_mutex);
1859 /* Unlink carefully: kallsyms could be walking list. */
1860 list_del_rcu(&mod->list);
1861 /* Remove this module from bug list, this uses list_del_rcu */
1862 module_bug_cleanup(mod);
1863 /* Wait for RCU synchronizing before releasing mod->list and buglist. */
1865 mutex_unlock(&module_mutex);
1867 /* This may be NULL, but that's OK */
1868 unset_module_init_ro_nx(mod);
1869 module_arch_freeing_init(mod);
1870 module_memfree(mod->module_init);
1872 percpu_modfree(mod);
1874 /* Free lock-classes; relies on the preceding sync_rcu(). */
1875 lockdep_free_key_range(mod->module_core, mod->core_size);
1877 /* Finally, free the core (containing the module structure) */
1878 unset_module_core_ro_nx(mod);
1879 module_memfree(mod->module_core);
1882 update_protections(current->mm);
1886 void *__symbol_get(const char *symbol)
1888 struct module *owner;
1889 const struct kernel_symbol *sym;
1892 sym = find_symbol(symbol, &owner, NULL, true, true);
1893 if (sym && strong_try_module_get(owner))
1897 return sym ? (void *)sym->value : NULL;
1899 EXPORT_SYMBOL_GPL(__symbol_get);
1902 * Ensure that an exported symbol [global namespace] does not already exist
1903 * in the kernel or in some other module's exported symbol table.
1905 * You must hold the module_mutex.
1907 static int verify_export_symbols(struct module *mod)
1910 struct module *owner;
1911 const struct kernel_symbol *s;
1913 const struct kernel_symbol *sym;
1916 { mod->syms, mod->num_syms },
1917 { mod->gpl_syms, mod->num_gpl_syms },
1918 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1919 #ifdef CONFIG_UNUSED_SYMBOLS
1920 { mod->unused_syms, mod->num_unused_syms },
1921 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1925 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1926 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1927 if (find_symbol(s->name, &owner, NULL, true, false)) {
1928 pr_err("%s: exports duplicate symbol %s"
1930 mod->name, s->name, module_name(owner));
1938 /* Change all symbols so that st_value encodes the pointer directly. */
1939 static int simplify_symbols(struct module *mod, const struct load_info *info)
1941 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
1942 Elf_Sym *sym = (void *)symsec->sh_addr;
1943 unsigned long secbase;
1946 const struct kernel_symbol *ksym;
1948 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
1949 const char *name = info->strtab + sym[i].st_name;
1951 switch (sym[i].st_shndx) {
1953 /* Ignore common symbols */
1954 if (!strncmp(name, "__gnu_lto", 9))
1957 /* We compiled with -fno-common. These are not
1958 supposed to happen. */
1959 pr_debug("Common symbol: %s\n", name);
1960 pr_warn("%s: please compile with -fno-common\n",
1966 /* Don't need to do anything */
1967 pr_debug("Absolute symbol: 0x%08lx\n",
1968 (long)sym[i].st_value);
1972 ksym = resolve_symbol_wait(mod, info, name);
1973 /* Ok if resolved. */
1974 if (ksym && !IS_ERR(ksym)) {
1975 sym[i].st_value = ksym->value;
1980 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1983 pr_warn("%s: Unknown symbol %s (err %li)\n",
1984 mod->name, name, PTR_ERR(ksym));
1985 ret = PTR_ERR(ksym) ?: -ENOENT;
1989 /* Divert to percpu allocation if a percpu var. */
1990 if (sym[i].st_shndx == info->index.pcpu)
1991 secbase = (unsigned long)mod_percpu(mod);
1993 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
1994 sym[i].st_value += secbase;
2002 static int apply_relocations(struct module *mod, const struct load_info *info)
2007 /* Now do relocations. */
2008 for (i = 1; i < info->hdr->e_shnum; i++) {
2009 unsigned int infosec = info->sechdrs[i].sh_info;
2011 /* Not a valid relocation section? */
2012 if (infosec >= info->hdr->e_shnum)
2015 /* Don't bother with non-allocated sections */
2016 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
2019 if (info->sechdrs[i].sh_type == SHT_REL)
2020 err = apply_relocate(info->sechdrs, info->strtab,
2021 info->index.sym, i, mod);
2022 else if (info->sechdrs[i].sh_type == SHT_RELA)
2023 err = apply_relocate_add(info->sechdrs, info->strtab,
2024 info->index.sym, i, mod);
2031 /* Additional bytes needed by arch in front of individual sections */
2032 unsigned int __weak arch_mod_section_prepend(struct module *mod,
2033 unsigned int section)
2035 /* default implementation just returns zero */
2039 /* Update size with this section: return offset. */
2040 static long get_offset(struct module *mod, unsigned int *size,
2041 Elf_Shdr *sechdr, unsigned int section)
2045 *size += arch_mod_section_prepend(mod, section);
2046 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2047 *size = ret + sechdr->sh_size;
2051 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2052 might -- code, read-only data, read-write data, small data. Tally
2053 sizes, and place the offsets into sh_entsize fields: high bit means it
2055 static void layout_sections(struct module *mod, struct load_info *info)
2057 static unsigned long const masks[][2] = {
2058 /* NOTE: all executable code must be the first section
2059 * in this array; otherwise modify the text_size
2060 * finder in the two loops below */
2061 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2062 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
2063 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2064 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2068 for (i = 0; i < info->hdr->e_shnum; i++)
2069 info->sechdrs[i].sh_entsize = ~0UL;
2071 pr_debug("Core section allocation order:\n");
2072 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2073 for (i = 0; i < info->hdr->e_shnum; ++i) {
2074 Elf_Shdr *s = &info->sechdrs[i];
2075 const char *sname = info->secstrings + s->sh_name;
2077 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2078 || (s->sh_flags & masks[m][1])
2079 || s->sh_entsize != ~0UL
2080 || strstarts(sname, ".init"))
2082 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
2083 pr_debug("\t%s\n", sname);
2086 case 0: /* executable */
2087 mod->core_size = debug_align(mod->core_size);
2088 mod->core_text_size = mod->core_size;
2090 case 1: /* RO: text and ro-data */
2091 mod->core_size = debug_align(mod->core_size);
2092 mod->core_ro_size = mod->core_size;
2094 case 3: /* whole core */
2095 mod->core_size = debug_align(mod->core_size);
2100 pr_debug("Init section allocation order:\n");
2101 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
2102 for (i = 0; i < info->hdr->e_shnum; ++i) {
2103 Elf_Shdr *s = &info->sechdrs[i];
2104 const char *sname = info->secstrings + s->sh_name;
2106 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2107 || (s->sh_flags & masks[m][1])
2108 || s->sh_entsize != ~0UL
2109 || !strstarts(sname, ".init"))
2111 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
2112 | INIT_OFFSET_MASK);
2113 pr_debug("\t%s\n", sname);
2116 case 0: /* executable */
2117 mod->init_size = debug_align(mod->init_size);
2118 mod->init_text_size = mod->init_size;
2120 case 1: /* RO: text and ro-data */
2121 mod->init_size = debug_align(mod->init_size);
2122 mod->init_ro_size = mod->init_size;
2124 case 3: /* whole init */
2125 mod->init_size = debug_align(mod->init_size);
2131 static void set_license(struct module *mod, const char *license)
2134 license = "unspecified";
2136 if (!license_is_gpl_compatible(license)) {
2137 if (!test_taint(TAINT_PROPRIETARY_MODULE))
2138 pr_warn("%s: module license '%s' taints kernel.\n",
2139 mod->name, license);
2140 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2141 LOCKDEP_NOW_UNRELIABLE);
2145 /* Parse tag=value strings from .modinfo section */
2146 static char *next_string(char *string, unsigned long *secsize)
2148 /* Skip non-zero chars */
2151 if ((*secsize)-- <= 1)
2155 /* Skip any zero padding. */
2156 while (!string[0]) {
2158 if ((*secsize)-- <= 1)
2164 static char *get_modinfo(struct load_info *info, const char *tag)
2167 unsigned int taglen = strlen(tag);
2168 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2169 unsigned long size = infosec->sh_size;
2171 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
2172 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2173 return p + taglen + 1;
2178 static void setup_modinfo(struct module *mod, struct load_info *info)
2180 struct module_attribute *attr;
2183 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2185 attr->setup(mod, get_modinfo(info, attr->attr.name));
2189 static void free_modinfo(struct module *mod)
2191 struct module_attribute *attr;
2194 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2200 #ifdef CONFIG_KALLSYMS
2202 /* lookup symbol in given range of kernel_symbols */
2203 static const struct kernel_symbol *lookup_symbol(const char *name,
2204 const struct kernel_symbol *start,
2205 const struct kernel_symbol *stop)
2207 return bsearch(name, start, stop - start,
2208 sizeof(struct kernel_symbol), cmp_name);
2211 static int is_exported(const char *name, unsigned long value,
2212 const struct module *mod)
2214 const struct kernel_symbol *ks;
2216 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
2218 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
2219 return ks != NULL && ks->value == value;
2223 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
2225 const Elf_Shdr *sechdrs = info->sechdrs;
2227 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2228 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2233 if (sym->st_shndx == SHN_UNDEF)
2235 if (sym->st_shndx == SHN_ABS)
2237 if (sym->st_shndx >= SHN_LORESERVE)
2239 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2241 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2242 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2243 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2245 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2250 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2251 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2256 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2263 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
2266 const Elf_Shdr *sec;
2268 if (src->st_shndx == SHN_UNDEF
2269 || src->st_shndx >= shnum
2273 sec = sechdrs + src->st_shndx;
2274 if (!(sec->sh_flags & SHF_ALLOC)
2275 #ifndef CONFIG_KALLSYMS_ALL
2276 || !(sec->sh_flags & SHF_EXECINSTR)
2278 || (sec->sh_entsize & INIT_OFFSET_MASK))
2285 * We only allocate and copy the strings needed by the parts of symtab
2286 * we keep. This is simple, but has the effect of making multiple
2287 * copies of duplicates. We could be more sophisticated, see
2288 * linux-kernel thread starting with
2289 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2291 static void layout_symtab(struct module *mod, struct load_info *info)
2293 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2294 Elf_Shdr *strsect = info->sechdrs + info->index.str;
2296 unsigned int i, nsrc, ndst, strtab_size = 0;
2298 /* Put symbol section at end of init part of module. */
2299 symsect->sh_flags |= SHF_ALLOC;
2300 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
2301 info->index.sym) | INIT_OFFSET_MASK;
2302 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
2304 src = (void *)info->hdr + symsect->sh_offset;
2305 nsrc = symsect->sh_size / sizeof(*src);
2307 /* Compute total space required for the core symbols' strtab. */
2308 for (ndst = i = 0; i < nsrc; i++) {
2310 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2311 strtab_size += strlen(&info->strtab[src[i].st_name])+1;
2316 /* Append room for core symbols at end of core part. */
2317 info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
2318 info->stroffs = mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym);
2319 mod->core_size += strtab_size;
2320 mod->core_size = debug_align(mod->core_size);
2322 /* Put string table section at end of init part of module. */
2323 strsect->sh_flags |= SHF_ALLOC;
2324 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
2325 info->index.str) | INIT_OFFSET_MASK;
2326 mod->init_size = debug_align(mod->init_size);
2327 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
2330 static void add_kallsyms(struct module *mod, const struct load_info *info)
2332 unsigned int i, ndst;
2336 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2338 mod->symtab = (void *)symsec->sh_addr;
2339 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2340 /* Make sure we get permanent strtab: don't use info->strtab. */
2341 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2343 /* Set types up while we still have access to sections. */
2344 for (i = 0; i < mod->num_symtab; i++)
2345 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
2347 mod->core_symtab = dst = mod->module_core + info->symoffs;
2348 mod->core_strtab = s = mod->module_core + info->stroffs;
2350 for (ndst = i = 0; i < mod->num_symtab; i++) {
2352 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2354 dst[ndst++].st_name = s - mod->core_strtab;
2355 s += strlcpy(s, &mod->strtab[src[i].st_name],
2359 mod->core_num_syms = ndst;
2362 static inline void layout_symtab(struct module *mod, struct load_info *info)
2366 static void add_kallsyms(struct module *mod, const struct load_info *info)
2369 #endif /* CONFIG_KALLSYMS */
2371 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2375 #ifdef CONFIG_DYNAMIC_DEBUG
2376 if (ddebug_add_module(debug, num, debug->modname))
2377 pr_err("dynamic debug error adding module: %s\n",
2382 static void dynamic_debug_remove(struct _ddebug *debug)
2385 ddebug_remove_module(debug->modname);
2388 void * __weak module_alloc(unsigned long size)
2390 return vmalloc_exec(size);
2393 static void *module_alloc_update_bounds(unsigned long size)
2395 void *ret = module_alloc(size);
2398 mutex_lock(&module_mutex);
2399 /* Update module bounds. */
2400 if ((unsigned long)ret < module_addr_min)
2401 module_addr_min = (unsigned long)ret;
2402 if ((unsigned long)ret + size > module_addr_max)
2403 module_addr_max = (unsigned long)ret + size;
2404 mutex_unlock(&module_mutex);
2409 #ifdef CONFIG_DEBUG_KMEMLEAK
2410 static void kmemleak_load_module(const struct module *mod,
2411 const struct load_info *info)
2415 /* only scan the sections containing data */
2416 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2418 for (i = 1; i < info->hdr->e_shnum; i++) {
2419 /* Scan all writable sections that's not executable */
2420 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
2421 !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
2422 (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
2425 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2426 info->sechdrs[i].sh_size, GFP_KERNEL);
2430 static inline void kmemleak_load_module(const struct module *mod,
2431 const struct load_info *info)
2436 #ifdef CONFIG_MODULE_SIG
2437 static int module_sig_check(struct load_info *info)
2440 const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2441 const void *mod = info->hdr;
2443 if (info->len > markerlen &&
2444 memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
2445 /* We truncate the module to discard the signature */
2446 info->len -= markerlen;
2447 err = mod_verify_sig(mod, &info->len);
2451 info->sig_ok = true;
2455 /* Not having a signature is only an error if we're strict. */
2456 if (err == -ENOKEY && !sig_enforce)
2461 #else /* !CONFIG_MODULE_SIG */
2462 static int module_sig_check(struct load_info *info)
2466 #endif /* !CONFIG_MODULE_SIG */
2468 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2469 static int elf_header_check(struct load_info *info)
2471 if (info->len < sizeof(*(info->hdr)))
2474 if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2475 || info->hdr->e_type != ET_REL
2476 || !elf_check_arch(info->hdr)
2477 || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2480 if (info->hdr->e_shoff >= info->len
2481 || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2482 info->len - info->hdr->e_shoff))
2488 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2490 static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len)
2493 unsigned long n = min(len, COPY_CHUNK_SIZE);
2495 if (copy_from_user(dst, usrc, n) != 0)
2505 /* Sets info->hdr and info->len. */
2506 static int copy_module_from_user(const void __user *umod, unsigned long len,
2507 struct load_info *info)
2512 if (info->len < sizeof(*(info->hdr)))
2515 err = security_kernel_module_from_file(NULL);
2519 /* Suck in entire file: we'll want most of it. */
2520 info->hdr = __vmalloc(info->len,
2521 GFP_KERNEL | __GFP_HIGHMEM | __GFP_NOWARN, PAGE_KERNEL);
2525 if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
2533 /* Sets info->hdr and info->len. */
2534 static int copy_module_from_fd(int fd, struct load_info *info)
2536 struct fd f = fdget(fd);
2545 err = security_kernel_module_from_file(f.file);
2549 err = vfs_getattr(&f.file->f_path, &stat);
2553 if (stat.size > INT_MAX) {
2558 /* Don't hand 0 to vmalloc, it whines. */
2559 if (stat.size == 0) {
2564 info->hdr = vmalloc(stat.size);
2571 while (pos < stat.size) {
2572 bytes = kernel_read(f.file, pos, (char *)(info->hdr) + pos,
2590 static void free_copy(struct load_info *info)
2595 static int rewrite_section_headers(struct load_info *info, int flags)
2599 /* This should always be true, but let's be sure. */
2600 info->sechdrs[0].sh_addr = 0;
2602 for (i = 1; i < info->hdr->e_shnum; i++) {
2603 Elf_Shdr *shdr = &info->sechdrs[i];
2604 if (shdr->sh_type != SHT_NOBITS
2605 && info->len < shdr->sh_offset + shdr->sh_size) {
2606 pr_err("Module len %lu truncated\n", info->len);
2610 /* Mark all sections sh_addr with their address in the
2612 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2614 #ifndef CONFIG_MODULE_UNLOAD
2615 /* Don't load .exit sections */
2616 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2617 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2621 /* Track but don't keep modinfo and version sections. */
2622 if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
2623 info->index.vers = 0; /* Pretend no __versions section! */
2625 info->index.vers = find_sec(info, "__versions");
2626 info->index.info = find_sec(info, ".modinfo");
2627 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2628 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2633 * Set up our basic convenience variables (pointers to section headers,
2634 * search for module section index etc), and do some basic section
2637 * Return the temporary module pointer (we'll replace it with the final
2638 * one when we move the module sections around).
2640 static struct module *setup_load_info(struct load_info *info, int flags)
2646 /* Set up the convenience variables */
2647 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2648 info->secstrings = (void *)info->hdr
2649 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2651 err = rewrite_section_headers(info, flags);
2653 return ERR_PTR(err);
2655 /* Find internal symbols and strings. */
2656 for (i = 1; i < info->hdr->e_shnum; i++) {
2657 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2658 info->index.sym = i;
2659 info->index.str = info->sechdrs[i].sh_link;
2660 info->strtab = (char *)info->hdr
2661 + info->sechdrs[info->index.str].sh_offset;
2666 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
2667 if (!info->index.mod) {
2668 pr_warn("No module found in object\n");
2669 return ERR_PTR(-ENOEXEC);
2671 /* This is temporary: point mod into copy of data. */
2672 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2674 if (info->index.sym == 0) {
2675 pr_warn("%s: module has no symbols (stripped?)\n", mod->name);
2676 return ERR_PTR(-ENOEXEC);
2679 info->index.pcpu = find_pcpusec(info);
2681 /* Check module struct version now, before we try to use module. */
2682 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2683 return ERR_PTR(-ENOEXEC);
2688 static int check_modinfo(struct module *mod, struct load_info *info, int flags)
2690 const char *modmagic = get_modinfo(info, "vermagic");
2693 if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2696 /* This is allowed: modprobe --force will invalidate it. */
2698 err = try_to_force_load(mod, "bad vermagic");
2701 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2702 pr_err("%s: version magic '%s' should be '%s'\n",
2703 mod->name, modmagic, vermagic);
2707 if (!get_modinfo(info, "intree"))
2708 add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
2710 if (get_modinfo(info, "staging")) {
2711 add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
2712 pr_warn("%s: module is from the staging directory, the quality "
2713 "is unknown, you have been warned.\n", mod->name);
2716 /* Set up license info based on the info section */
2717 set_license(mod, get_modinfo(info, "license"));
2722 static int find_module_sections(struct module *mod, struct load_info *info)
2724 mod->kp = section_objs(info, "__param",
2725 sizeof(*mod->kp), &mod->num_kp);
2726 mod->syms = section_objs(info, "__ksymtab",
2727 sizeof(*mod->syms), &mod->num_syms);
2728 mod->crcs = section_addr(info, "__kcrctab");
2729 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2730 sizeof(*mod->gpl_syms),
2731 &mod->num_gpl_syms);
2732 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2733 mod->gpl_future_syms = section_objs(info,
2734 "__ksymtab_gpl_future",
2735 sizeof(*mod->gpl_future_syms),
2736 &mod->num_gpl_future_syms);
2737 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
2739 #ifdef CONFIG_UNUSED_SYMBOLS
2740 mod->unused_syms = section_objs(info, "__ksymtab_unused",
2741 sizeof(*mod->unused_syms),
2742 &mod->num_unused_syms);
2743 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2744 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
2745 sizeof(*mod->unused_gpl_syms),
2746 &mod->num_unused_gpl_syms);
2747 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
2749 #ifdef CONFIG_CONSTRUCTORS
2750 mod->ctors = section_objs(info, ".ctors",
2751 sizeof(*mod->ctors), &mod->num_ctors);
2753 mod->ctors = section_objs(info, ".init_array",
2754 sizeof(*mod->ctors), &mod->num_ctors);
2755 else if (find_sec(info, ".init_array")) {
2757 * This shouldn't happen with same compiler and binutils
2758 * building all parts of the module.
2760 pr_warn("%s: has both .ctors and .init_array.\n",
2766 #ifdef CONFIG_TRACEPOINTS
2767 mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2768 sizeof(*mod->tracepoints_ptrs),
2769 &mod->num_tracepoints);
2771 #ifdef HAVE_JUMP_LABEL
2772 mod->jump_entries = section_objs(info, "__jump_table",
2773 sizeof(*mod->jump_entries),
2774 &mod->num_jump_entries);
2776 #ifdef CONFIG_EVENT_TRACING
2777 mod->trace_events = section_objs(info, "_ftrace_events",
2778 sizeof(*mod->trace_events),
2779 &mod->num_trace_events);
2780 mod->trace_enums = section_objs(info, "_ftrace_enum_map",
2781 sizeof(*mod->trace_enums),
2782 &mod->num_trace_enums);
2784 #ifdef CONFIG_TRACING
2785 mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2786 sizeof(*mod->trace_bprintk_fmt_start),
2787 &mod->num_trace_bprintk_fmt);
2789 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2790 /* sechdrs[0].sh_size is always zero */
2791 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
2792 sizeof(*mod->ftrace_callsites),
2793 &mod->num_ftrace_callsites);
2796 mod->extable = section_objs(info, "__ex_table",
2797 sizeof(*mod->extable), &mod->num_exentries);
2799 if (section_addr(info, "__obsparm"))
2800 pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
2802 info->debug = section_objs(info, "__verbose",
2803 sizeof(*info->debug), &info->num_debug);
2808 static int move_module(struct module *mod, struct load_info *info)
2813 /* Do the allocs. */
2814 ptr = module_alloc_update_bounds(mod->core_size);
2816 * The pointer to this block is stored in the module structure
2817 * which is inside the block. Just mark it as not being a
2820 kmemleak_not_leak(ptr);
2824 memset(ptr, 0, mod->core_size);
2825 mod->module_core = ptr;
2827 if (mod->init_size) {
2828 ptr = module_alloc_update_bounds(mod->init_size);
2830 * The pointer to this block is stored in the module structure
2831 * which is inside the block. This block doesn't need to be
2832 * scanned as it contains data and code that will be freed
2833 * after the module is initialized.
2835 kmemleak_ignore(ptr);
2837 module_memfree(mod->module_core);
2840 memset(ptr, 0, mod->init_size);
2841 mod->module_init = ptr;
2843 mod->module_init = NULL;
2845 /* Transfer each section which specifies SHF_ALLOC */
2846 pr_debug("final section addresses:\n");
2847 for (i = 0; i < info->hdr->e_shnum; i++) {
2849 Elf_Shdr *shdr = &info->sechdrs[i];
2851 if (!(shdr->sh_flags & SHF_ALLOC))
2854 if (shdr->sh_entsize & INIT_OFFSET_MASK)
2855 dest = mod->module_init
2856 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
2858 dest = mod->module_core + shdr->sh_entsize;
2860 if (shdr->sh_type != SHT_NOBITS)
2861 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2862 /* Update sh_addr to point to copy in image. */
2863 shdr->sh_addr = (unsigned long)dest;
2864 pr_debug("\t0x%lx %s\n",
2865 (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
2871 static int check_module_license_and_versions(struct module *mod)
2874 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2875 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2876 * using GPL-only symbols it needs.
2878 if (strcmp(mod->name, "ndiswrapper") == 0)
2879 add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
2881 /* driverloader was caught wrongly pretending to be under GPL */
2882 if (strcmp(mod->name, "driverloader") == 0)
2883 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2884 LOCKDEP_NOW_UNRELIABLE);
2886 /* lve claims to be GPL but upstream won't provide source */
2887 if (strcmp(mod->name, "lve") == 0)
2888 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2889 LOCKDEP_NOW_UNRELIABLE);
2891 #ifdef CONFIG_MODVERSIONS
2892 if ((mod->num_syms && !mod->crcs)
2893 || (mod->num_gpl_syms && !mod->gpl_crcs)
2894 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2895 #ifdef CONFIG_UNUSED_SYMBOLS
2896 || (mod->num_unused_syms && !mod->unused_crcs)
2897 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2900 return try_to_force_load(mod,
2901 "no versions for exported symbols");
2907 static void flush_module_icache(const struct module *mod)
2909 mm_segment_t old_fs;
2911 /* flush the icache in correct context */
2916 * Flush the instruction cache, since we've played with text.
2917 * Do it before processing of module parameters, so the module
2918 * can provide parameter accessor functions of its own.
2920 if (mod->module_init)
2921 flush_icache_range((unsigned long)mod->module_init,
2922 (unsigned long)mod->module_init
2924 flush_icache_range((unsigned long)mod->module_core,
2925 (unsigned long)mod->module_core + mod->core_size);
2930 int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
2938 static struct module *layout_and_allocate(struct load_info *info, int flags)
2940 /* Module within temporary copy. */
2944 mod = setup_load_info(info, flags);
2948 err = check_modinfo(mod, info, flags);
2950 return ERR_PTR(err);
2952 /* Allow arches to frob section contents and sizes. */
2953 err = module_frob_arch_sections(info->hdr, info->sechdrs,
2954 info->secstrings, mod);
2956 return ERR_PTR(err);
2958 /* We will do a special allocation for per-cpu sections later. */
2959 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
2961 /* Determine total sizes, and put offsets in sh_entsize. For now
2962 this is done generically; there doesn't appear to be any
2963 special cases for the architectures. */
2964 layout_sections(mod, info);
2965 layout_symtab(mod, info);
2967 /* Allocate and move to the final place */
2968 err = move_module(mod, info);
2970 return ERR_PTR(err);
2972 /* Module has been copied to its final place now: return it. */
2973 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2974 kmemleak_load_module(mod, info);
2978 /* mod is no longer valid after this! */
2979 static void module_deallocate(struct module *mod, struct load_info *info)
2981 percpu_modfree(mod);
2982 module_arch_freeing_init(mod);
2983 module_memfree(mod->module_init);
2984 module_memfree(mod->module_core);
2987 int __weak module_finalize(const Elf_Ehdr *hdr,
2988 const Elf_Shdr *sechdrs,
2994 static int post_relocation(struct module *mod, const struct load_info *info)
2996 /* Sort exception table now relocations are done. */
2997 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2999 /* Copy relocated percpu area over. */
3000 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
3001 info->sechdrs[info->index.pcpu].sh_size);
3003 /* Setup kallsyms-specific fields. */
3004 add_kallsyms(mod, info);
3006 /* Arch-specific module finalizing. */
3007 return module_finalize(info->hdr, info->sechdrs, mod);
3010 /* Is this module of this name done loading? No locks held. */
3011 static bool finished_loading(const char *name)
3017 * The module_mutex should not be a heavily contended lock;
3018 * if we get the occasional sleep here, we'll go an extra iteration
3019 * in the wait_event_interruptible(), which is harmless.
3021 sched_annotate_sleep();
3022 mutex_lock(&module_mutex);
3023 mod = find_module_all(name, strlen(name), true);
3024 ret = !mod || mod->state == MODULE_STATE_LIVE
3025 || mod->state == MODULE_STATE_GOING;
3026 mutex_unlock(&module_mutex);
3031 /* Call module constructors. */
3032 static void do_mod_ctors(struct module *mod)
3034 #ifdef CONFIG_CONSTRUCTORS
3037 for (i = 0; i < mod->num_ctors; i++)
3042 /* For freeing module_init on success, in case kallsyms traversing */
3043 struct mod_initfree {
3044 struct rcu_head rcu;
3048 static void do_free_init(struct rcu_head *head)
3050 struct mod_initfree *m = container_of(head, struct mod_initfree, rcu);
3051 module_memfree(m->module_init);
3056 * This is where the real work happens.
3058 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3059 * helper command 'lx-symbols'.
3061 static noinline int do_init_module(struct module *mod)
3064 struct mod_initfree *freeinit;
3066 freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
3071 freeinit->module_init = mod->module_init;
3074 * We want to find out whether @mod uses async during init. Clear
3075 * PF_USED_ASYNC. async_schedule*() will set it.
3077 current->flags &= ~PF_USED_ASYNC;
3080 /* Start the module */
3081 if (mod->init != NULL)
3082 ret = do_one_initcall(mod->init);
3084 goto fail_free_freeinit;
3087 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3088 "follow 0/-E convention\n"
3089 "%s: loading module anyway...\n",
3090 __func__, mod->name, ret, __func__);
3094 /* Now it's a first class citizen! */
3095 mod->state = MODULE_STATE_LIVE;
3096 blocking_notifier_call_chain(&module_notify_list,
3097 MODULE_STATE_LIVE, mod);
3100 * We need to finish all async code before the module init sequence
3101 * is done. This has potential to deadlock. For example, a newly
3102 * detected block device can trigger request_module() of the
3103 * default iosched from async probing task. Once userland helper
3104 * reaches here, async_synchronize_full() will wait on the async
3105 * task waiting on request_module() and deadlock.
3107 * This deadlock is avoided by perfomring async_synchronize_full()
3108 * iff module init queued any async jobs. This isn't a full
3109 * solution as it will deadlock the same if module loading from
3110 * async jobs nests more than once; however, due to the various
3111 * constraints, this hack seems to be the best option for now.
3112 * Please refer to the following thread for details.
3114 * http://thread.gmane.org/gmane.linux.kernel/1420814
3116 if (current->flags & PF_USED_ASYNC)
3117 async_synchronize_full();
3119 mutex_lock(&module_mutex);
3120 /* Drop initial reference. */
3122 trim_init_extable(mod);
3123 #ifdef CONFIG_KALLSYMS
3124 mod->num_symtab = mod->core_num_syms;
3125 mod->symtab = mod->core_symtab;
3126 mod->strtab = mod->core_strtab;
3128 unset_module_init_ro_nx(mod);
3129 module_arch_freeing_init(mod);
3130 mod->module_init = NULL;
3132 mod->init_ro_size = 0;
3133 mod->init_text_size = 0;
3135 * We want to free module_init, but be aware that kallsyms may be
3136 * walking this with preempt disabled. In all the failure paths,
3137 * we call synchronize_rcu/synchronize_sched, but we don't want
3138 * to slow down the success path, so use actual RCU here.
3140 call_rcu(&freeinit->rcu, do_free_init);
3141 mutex_unlock(&module_mutex);
3142 wake_up_all(&module_wq);
3149 /* Try to protect us from buggy refcounters. */
3150 mod->state = MODULE_STATE_GOING;
3151 synchronize_sched();
3153 blocking_notifier_call_chain(&module_notify_list,
3154 MODULE_STATE_GOING, mod);
3156 wake_up_all(&module_wq);
3160 static int may_init_module(void)
3162 if (!capable(CAP_SYS_MODULE) || modules_disabled)
3169 * We try to place it in the list now to make sure it's unique before
3170 * we dedicate too many resources. In particular, temporary percpu
3171 * memory exhaustion.
3173 static int add_unformed_module(struct module *mod)
3178 mod->state = MODULE_STATE_UNFORMED;
3181 mutex_lock(&module_mutex);
3182 old = find_module_all(mod->name, strlen(mod->name), true);
3184 if (old->state == MODULE_STATE_COMING
3185 || old->state == MODULE_STATE_UNFORMED) {
3186 /* Wait in case it fails to load. */
3187 mutex_unlock(&module_mutex);
3188 err = wait_event_interruptible(module_wq,
3189 finished_loading(mod->name));
3197 list_add_rcu(&mod->list, &modules);
3201 mutex_unlock(&module_mutex);
3206 static int complete_formation(struct module *mod, struct load_info *info)
3210 mutex_lock(&module_mutex);
3212 /* Find duplicate symbols (must be called under lock). */
3213 err = verify_export_symbols(mod);
3217 /* This relies on module_mutex for list integrity. */
3218 module_bug_finalize(info->hdr, info->sechdrs, mod);
3220 /* Set RO and NX regions for core */
3221 set_section_ro_nx(mod->module_core,
3222 mod->core_text_size,
3226 /* Set RO and NX regions for init */
3227 set_section_ro_nx(mod->module_init,
3228 mod->init_text_size,
3232 /* Mark state as coming so strong_try_module_get() ignores us,
3233 * but kallsyms etc. can see us. */
3234 mod->state = MODULE_STATE_COMING;
3235 mutex_unlock(&module_mutex);
3237 blocking_notifier_call_chain(&module_notify_list,
3238 MODULE_STATE_COMING, mod);
3242 mutex_unlock(&module_mutex);
3246 static int unknown_module_param_cb(char *param, char *val, const char *modname)
3248 /* Check for magic 'dyndbg' arg */
3249 int ret = ddebug_dyndbg_module_param_cb(param, val, modname);
3251 pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
3255 /* Allocate and load the module: note that size of section 0 is always
3256 zero, and we rely on this for optional sections. */
3257 static int load_module(struct load_info *info, const char __user *uargs,
3264 err = module_sig_check(info);
3268 err = elf_header_check(info);
3272 /* Figure out module layout, and allocate all the memory. */
3273 mod = layout_and_allocate(info, flags);
3279 /* Reserve our place in the list. */
3280 err = add_unformed_module(mod);
3284 #ifdef CONFIG_MODULE_SIG
3285 mod->sig_ok = info->sig_ok;
3287 pr_notice_once("%s: module verification failed: signature "
3288 "and/or required key missing - tainting "
3289 "kernel\n", mod->name);
3290 add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
3294 /* To avoid stressing percpu allocator, do this once we're unique. */
3295 err = percpu_modalloc(mod, info);
3299 /* Now module is in final location, initialize linked lists, etc. */
3300 err = module_unload_init(mod);
3304 /* Now we've got everything in the final locations, we can
3305 * find optional sections. */
3306 err = find_module_sections(mod, info);
3310 err = check_module_license_and_versions(mod);
3314 /* Set up MODINFO_ATTR fields */
3315 setup_modinfo(mod, info);
3317 /* Fix up syms, so that st_value is a pointer to location. */
3318 err = simplify_symbols(mod, info);
3322 err = apply_relocations(mod, info);
3326 err = post_relocation(mod, info);
3330 flush_module_icache(mod);
3332 /* Now copy in args */
3333 mod->args = strndup_user(uargs, ~0UL >> 1);
3334 if (IS_ERR(mod->args)) {
3335 err = PTR_ERR(mod->args);
3336 goto free_arch_cleanup;
3339 dynamic_debug_setup(info->debug, info->num_debug);
3341 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3342 ftrace_module_init(mod);
3344 /* Finally it's fully formed, ready to start executing. */
3345 err = complete_formation(mod, info);
3347 goto ddebug_cleanup;
3349 /* Module is ready to execute: parsing args may do that. */
3350 after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
3351 -32768, 32767, unknown_module_param_cb);
3352 if (IS_ERR(after_dashes)) {
3353 err = PTR_ERR(after_dashes);
3355 } else if (after_dashes) {
3356 pr_warn("%s: parameters '%s' after `--' ignored\n",
3357 mod->name, after_dashes);
3360 /* Link in to syfs. */
3361 err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3365 /* Get rid of temporary copy. */
3369 trace_module_load(mod);
3371 return do_init_module(mod);
3374 /* module_bug_cleanup needs module_mutex protection */
3375 mutex_lock(&module_mutex);
3376 module_bug_cleanup(mod);
3377 mutex_unlock(&module_mutex);
3379 /* we can't deallocate the module until we clear memory protection */
3380 unset_module_init_ro_nx(mod);
3381 unset_module_core_ro_nx(mod);
3384 dynamic_debug_remove(info->debug);
3385 synchronize_sched();
3388 module_arch_cleanup(mod);
3392 module_unload_free(mod);
3394 mutex_lock(&module_mutex);
3395 /* Unlink carefully: kallsyms could be walking list. */
3396 list_del_rcu(&mod->list);
3397 wake_up_all(&module_wq);
3398 /* Wait for RCU synchronizing before releasing mod->list. */
3400 mutex_unlock(&module_mutex);
3402 /* Free lock-classes; relies on the preceding sync_rcu() */
3403 lockdep_free_key_range(mod->module_core, mod->core_size);
3405 module_deallocate(mod, info);
3411 SYSCALL_DEFINE3(init_module, void __user *, umod,
3412 unsigned long, len, const char __user *, uargs)
3415 struct load_info info = { };
3417 err = may_init_module();
3421 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3424 err = copy_module_from_user(umod, len, &info);
3428 return load_module(&info, uargs, 0);
3431 SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3434 struct load_info info = { };
3436 err = may_init_module();
3440 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3442 if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3443 |MODULE_INIT_IGNORE_VERMAGIC))
3446 err = copy_module_from_fd(fd, &info);
3450 return load_module(&info, uargs, flags);
3453 static inline int within(unsigned long addr, void *start, unsigned long size)
3455 return ((void *)addr >= start && (void *)addr < start + size);
3458 #ifdef CONFIG_KALLSYMS
3460 * This ignores the intensely annoying "mapping symbols" found
3461 * in ARM ELF files: $a, $t and $d.
3463 static inline int is_arm_mapping_symbol(const char *str)
3465 if (str[0] == '.' && str[1] == 'L')
3467 return str[0] == '$' && strchr("axtd", str[1])
3468 && (str[2] == '\0' || str[2] == '.');
3471 static const char *get_ksymbol(struct module *mod,
3473 unsigned long *size,
3474 unsigned long *offset)
3476 unsigned int i, best = 0;
3477 unsigned long nextval;
3479 /* At worse, next value is at end of module */
3480 if (within_module_init(addr, mod))
3481 nextval = (unsigned long)mod->module_init+mod->init_text_size;
3483 nextval = (unsigned long)mod->module_core+mod->core_text_size;
3485 /* Scan for closest preceding symbol, and next symbol. (ELF
3486 starts real symbols at 1). */
3487 for (i = 1; i < mod->num_symtab; i++) {
3488 if (mod->symtab[i].st_shndx == SHN_UNDEF)
3491 /* We ignore unnamed symbols: they're uninformative
3492 * and inserted at a whim. */
3493 if (mod->symtab[i].st_value <= addr
3494 && mod->symtab[i].st_value > mod->symtab[best].st_value
3495 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3496 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3498 if (mod->symtab[i].st_value > addr
3499 && mod->symtab[i].st_value < nextval
3500 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3501 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3502 nextval = mod->symtab[i].st_value;
3509 *size = nextval - mod->symtab[best].st_value;
3511 *offset = addr - mod->symtab[best].st_value;
3512 return mod->strtab + mod->symtab[best].st_name;
3515 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3516 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3517 const char *module_address_lookup(unsigned long addr,
3518 unsigned long *size,
3519 unsigned long *offset,
3524 const char *ret = NULL;
3527 list_for_each_entry_rcu(mod, &modules, list) {
3528 if (mod->state == MODULE_STATE_UNFORMED)
3530 if (within_module(addr, mod)) {
3532 *modname = mod->name;
3533 ret = get_ksymbol(mod, addr, size, offset);
3537 /* Make a copy in here where it's safe */
3539 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
3546 int lookup_module_symbol_name(unsigned long addr, char *symname)
3551 list_for_each_entry_rcu(mod, &modules, list) {
3552 if (mod->state == MODULE_STATE_UNFORMED)
3554 if (within_module(addr, mod)) {
3557 sym = get_ksymbol(mod, addr, NULL, NULL);
3560 strlcpy(symname, sym, KSYM_NAME_LEN);
3570 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
3571 unsigned long *offset, char *modname, char *name)
3576 list_for_each_entry_rcu(mod, &modules, list) {
3577 if (mod->state == MODULE_STATE_UNFORMED)
3579 if (within_module(addr, mod)) {
3582 sym = get_ksymbol(mod, addr, size, offset);
3586 strlcpy(modname, mod->name, MODULE_NAME_LEN);
3588 strlcpy(name, sym, KSYM_NAME_LEN);
3598 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
3599 char *name, char *module_name, int *exported)
3604 list_for_each_entry_rcu(mod, &modules, list) {
3605 if (mod->state == MODULE_STATE_UNFORMED)
3607 if (symnum < mod->num_symtab) {
3608 *value = mod->symtab[symnum].st_value;
3609 *type = mod->symtab[symnum].st_info;
3610 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
3612 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
3613 *exported = is_exported(name, *value, mod);
3617 symnum -= mod->num_symtab;
3623 static unsigned long mod_find_symname(struct module *mod, const char *name)
3627 for (i = 0; i < mod->num_symtab; i++)
3628 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
3629 mod->symtab[i].st_info != 'U')
3630 return mod->symtab[i].st_value;
3634 /* Look for this name: can be of form module:name. */
3635 unsigned long module_kallsyms_lookup_name(const char *name)
3639 unsigned long ret = 0;
3641 /* Don't lock: we're in enough trouble already. */
3643 if ((colon = strchr(name, ':')) != NULL) {
3644 if ((mod = find_module_all(name, colon - name, false)) != NULL)
3645 ret = mod_find_symname(mod, colon+1);
3647 list_for_each_entry_rcu(mod, &modules, list) {
3648 if (mod->state == MODULE_STATE_UNFORMED)
3650 if ((ret = mod_find_symname(mod, name)) != 0)
3658 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3659 struct module *, unsigned long),
3666 list_for_each_entry(mod, &modules, list) {
3667 if (mod->state == MODULE_STATE_UNFORMED)
3669 for (i = 0; i < mod->num_symtab; i++) {
3670 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
3671 mod, mod->symtab[i].st_value);
3678 #endif /* CONFIG_KALLSYMS */
3680 static char *module_flags(struct module *mod, char *buf)
3684 BUG_ON(mod->state == MODULE_STATE_UNFORMED);
3686 mod->state == MODULE_STATE_GOING ||
3687 mod->state == MODULE_STATE_COMING) {
3689 bx += module_flags_taint(mod, buf + bx);
3690 /* Show a - for module-is-being-unloaded */
3691 if (mod->state == MODULE_STATE_GOING)
3693 /* Show a + for module-is-being-loaded */
3694 if (mod->state == MODULE_STATE_COMING)
3703 #ifdef CONFIG_PROC_FS
3704 /* Called by the /proc file system to return a list of modules. */
3705 static void *m_start(struct seq_file *m, loff_t *pos)
3707 mutex_lock(&module_mutex);
3708 return seq_list_start(&modules, *pos);
3711 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3713 return seq_list_next(p, &modules, pos);
3716 static void m_stop(struct seq_file *m, void *p)
3718 mutex_unlock(&module_mutex);
3721 static int m_show(struct seq_file *m, void *p)
3723 struct module *mod = list_entry(p, struct module, list);
3726 /* We always ignore unformed modules. */
3727 if (mod->state == MODULE_STATE_UNFORMED)
3730 seq_printf(m, "%s %u",
3731 mod->name, mod->init_size + mod->core_size);
3732 print_unload_info(m, mod);
3734 /* Informative for users. */
3735 seq_printf(m, " %s",
3736 mod->state == MODULE_STATE_GOING ? "Unloading" :
3737 mod->state == MODULE_STATE_COMING ? "Loading" :
3739 /* Used by oprofile and other similar tools. */
3740 seq_printf(m, " 0x%pK", mod->module_core);
3744 seq_printf(m, " %s", module_flags(mod, buf));
3750 /* Format: modulename size refcount deps address
3752 Where refcount is a number or -, and deps is a comma-separated list
3755 static const struct seq_operations modules_op = {
3762 static int modules_open(struct inode *inode, struct file *file)
3764 return seq_open(file, &modules_op);
3767 static const struct file_operations proc_modules_operations = {
3768 .open = modules_open,
3770 .llseek = seq_lseek,
3771 .release = seq_release,
3774 static int __init proc_modules_init(void)
3776 proc_create("modules", 0, NULL, &proc_modules_operations);
3779 module_init(proc_modules_init);
3782 /* Given an address, look for it in the module exception tables. */
3783 const struct exception_table_entry *search_module_extables(unsigned long addr)
3785 const struct exception_table_entry *e = NULL;
3789 list_for_each_entry_rcu(mod, &modules, list) {
3790 if (mod->state == MODULE_STATE_UNFORMED)
3792 if (mod->num_exentries == 0)
3795 e = search_extable(mod->extable,
3796 mod->extable + mod->num_exentries - 1,
3803 /* Now, if we found one, we are running inside it now, hence
3804 we cannot unload the module, hence no refcnt needed. */
3809 * is_module_address - is this address inside a module?
3810 * @addr: the address to check.
3812 * See is_module_text_address() if you simply want to see if the address
3813 * is code (not data).
3815 bool is_module_address(unsigned long addr)
3820 ret = __module_address(addr) != NULL;
3827 * __module_address - get the module which contains an address.
3828 * @addr: the address.
3830 * Must be called with preempt disabled or module mutex held so that
3831 * module doesn't get freed during this.
3833 struct module *__module_address(unsigned long addr)
3837 if (addr < module_addr_min || addr > module_addr_max)
3840 list_for_each_entry_rcu(mod, &modules, list) {
3841 if (mod->state == MODULE_STATE_UNFORMED)
3843 if (within_module(addr, mod))
3848 EXPORT_SYMBOL_GPL(__module_address);
3851 * is_module_text_address - is this address inside module code?
3852 * @addr: the address to check.
3854 * See is_module_address() if you simply want to see if the address is
3855 * anywhere in a module. See kernel_text_address() for testing if an
3856 * address corresponds to kernel or module code.
3858 bool is_module_text_address(unsigned long addr)
3863 ret = __module_text_address(addr) != NULL;
3870 * __module_text_address - get the module whose code contains an address.
3871 * @addr: the address.
3873 * Must be called with preempt disabled or module mutex held so that
3874 * module doesn't get freed during this.
3876 struct module *__module_text_address(unsigned long addr)
3878 struct module *mod = __module_address(addr);
3880 /* Make sure it's within the text section. */
3881 if (!within(addr, mod->module_init, mod->init_text_size)
3882 && !within(addr, mod->module_core, mod->core_text_size))
3887 EXPORT_SYMBOL_GPL(__module_text_address);
3889 /* Don't grab lock, we're oopsing. */
3890 void print_modules(void)
3895 printk(KERN_DEFAULT "Modules linked in:");
3896 /* Most callers should already have preempt disabled, but make sure */
3898 list_for_each_entry_rcu(mod, &modules, list) {
3899 if (mod->state == MODULE_STATE_UNFORMED)
3901 pr_cont(" %s%s", mod->name, module_flags(mod, buf));
3904 if (last_unloaded_module[0])
3905 pr_cont(" [last unloaded: %s]", last_unloaded_module);
3909 #ifdef CONFIG_MODVERSIONS
3910 /* Generate the signature for all relevant module structures here.
3911 * If these change, we don't want to try to parse the module. */
3912 void module_layout(struct module *mod,
3913 struct modversion_info *ver,
3914 struct kernel_param *kp,
3915 struct kernel_symbol *ks,
3916 struct tracepoint * const *tp)
3919 EXPORT_SYMBOL(module_layout);