2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 #include <linux/export.h>
20 #include <linux/moduleloader.h>
21 #include <linux/trace_events.h>
22 #include <linux/init.h>
23 #include <linux/kallsyms.h>
24 #include <linux/file.h>
26 #include <linux/sysfs.h>
27 #include <linux/kernel.h>
28 #include <linux/slab.h>
29 #include <linux/vmalloc.h>
30 #include <linux/elf.h>
31 #include <linux/proc_fs.h>
32 #include <linux/security.h>
33 #include <linux/seq_file.h>
34 #include <linux/syscalls.h>
35 #include <linux/fcntl.h>
36 #include <linux/rcupdate.h>
37 #include <linux/capability.h>
38 #include <linux/cpu.h>
39 #include <linux/moduleparam.h>
40 #include <linux/errno.h>
41 #include <linux/err.h>
42 #include <linux/vermagic.h>
43 #include <linux/notifier.h>
44 #include <linux/sched.h>
45 #include <linux/device.h>
46 #include <linux/string.h>
47 #include <linux/mutex.h>
48 #include <linux/rculist.h>
49 #include <asm/uaccess.h>
50 #include <asm/cacheflush.h>
51 #include <asm/mmu_context.h>
52 #include <linux/license.h>
53 #include <asm/sections.h>
54 #include <linux/tracepoint.h>
55 #include <linux/ftrace.h>
56 #include <linux/async.h>
57 #include <linux/percpu.h>
58 #include <linux/kmemleak.h>
59 #include <linux/jump_label.h>
60 #include <linux/pfn.h>
61 #include <linux/bsearch.h>
62 #include <uapi/linux/module.h>
63 #include "module-internal.h"
65 #define CREATE_TRACE_POINTS
66 #include <trace/events/module.h>
68 #ifndef ARCH_SHF_SMALL
69 #define ARCH_SHF_SMALL 0
73 * Modules' sections will be aligned on page boundaries
74 * to ensure complete separation of code and data, but
75 * only when CONFIG_DEBUG_SET_MODULE_RONX=y
77 #ifdef CONFIG_DEBUG_SET_MODULE_RONX
78 # define debug_align(X) ALIGN(X, PAGE_SIZE)
80 # define debug_align(X) (X)
83 /* If this is set, the section belongs in the init part of the module */
84 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
88 * 1) List of modules (also safely readable with preempt_disable),
89 * 2) module_use links,
90 * 3) module_addr_min/module_addr_max.
91 * (delete and add uses RCU list operations). */
92 DEFINE_MUTEX(module_mutex
);
93 EXPORT_SYMBOL_GPL(module_mutex
);
94 static LIST_HEAD(modules
);
96 #ifdef CONFIG_MODULES_TREE_LOOKUP
99 * Use a latched RB-tree for __module_address(); this allows us to use
100 * RCU-sched lookups of the address from any context.
102 * This is conditional on PERF_EVENTS || TRACING because those can really hit
103 * __module_address() hard by doing a lot of stack unwinding; potentially from
107 static __always_inline
unsigned long __mod_tree_val(struct latch_tree_node
*n
)
109 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
111 return (unsigned long)layout
->base
;
114 static __always_inline
unsigned long __mod_tree_size(struct latch_tree_node
*n
)
116 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
118 return (unsigned long)layout
->size
;
121 static __always_inline
bool
122 mod_tree_less(struct latch_tree_node
*a
, struct latch_tree_node
*b
)
124 return __mod_tree_val(a
) < __mod_tree_val(b
);
127 static __always_inline
int
128 mod_tree_comp(void *key
, struct latch_tree_node
*n
)
130 unsigned long val
= (unsigned long)key
;
131 unsigned long start
, end
;
133 start
= __mod_tree_val(n
);
137 end
= start
+ __mod_tree_size(n
);
144 static const struct latch_tree_ops mod_tree_ops
= {
145 .less
= mod_tree_less
,
146 .comp
= mod_tree_comp
,
149 static struct mod_tree_root
{
150 struct latch_tree_root root
;
151 unsigned long addr_min
;
152 unsigned long addr_max
;
153 } mod_tree __cacheline_aligned
= {
157 #define module_addr_min mod_tree.addr_min
158 #define module_addr_max mod_tree.addr_max
160 static noinline
void __mod_tree_insert(struct mod_tree_node
*node
)
162 latch_tree_insert(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
165 static void __mod_tree_remove(struct mod_tree_node
*node
)
167 latch_tree_erase(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
171 * These modifications: insert, remove_init and remove; are serialized by the
174 static void mod_tree_insert(struct module
*mod
)
176 mod
->core_layout
.mtn
.mod
= mod
;
177 mod
->init_layout
.mtn
.mod
= mod
;
179 __mod_tree_insert(&mod
->core_layout
.mtn
);
180 if (mod
->init_layout
.size
)
181 __mod_tree_insert(&mod
->init_layout
.mtn
);
184 static void mod_tree_remove_init(struct module
*mod
)
186 if (mod
->init_layout
.size
)
187 __mod_tree_remove(&mod
->init_layout
.mtn
);
190 static void mod_tree_remove(struct module
*mod
)
192 __mod_tree_remove(&mod
->core_layout
.mtn
);
193 mod_tree_remove_init(mod
);
196 static struct module
*mod_find(unsigned long addr
)
198 struct latch_tree_node
*ltn
;
200 ltn
= latch_tree_find((void *)addr
, &mod_tree
.root
, &mod_tree_ops
);
204 return container_of(ltn
, struct mod_tree_node
, node
)->mod
;
207 #else /* MODULES_TREE_LOOKUP */
209 static unsigned long module_addr_min
= -1UL, module_addr_max
= 0;
211 static void mod_tree_insert(struct module
*mod
) { }
212 static void mod_tree_remove_init(struct module
*mod
) { }
213 static void mod_tree_remove(struct module
*mod
) { }
215 static struct module
*mod_find(unsigned long addr
)
219 list_for_each_entry_rcu(mod
, &modules
, list
) {
220 if (within_module(addr
, mod
))
227 #endif /* MODULES_TREE_LOOKUP */
230 * Bounds of module text, for speeding up __module_address.
231 * Protected by module_mutex.
233 static void __mod_update_bounds(void *base
, unsigned int size
)
235 unsigned long min
= (unsigned long)base
;
236 unsigned long max
= min
+ size
;
238 if (min
< module_addr_min
)
239 module_addr_min
= min
;
240 if (max
> module_addr_max
)
241 module_addr_max
= max
;
244 static void mod_update_bounds(struct module
*mod
)
246 __mod_update_bounds(mod
->core_layout
.base
, mod
->core_layout
.size
);
247 if (mod
->init_layout
.size
)
248 __mod_update_bounds(mod
->init_layout
.base
, mod
->init_layout
.size
);
251 #ifdef CONFIG_KGDB_KDB
252 struct list_head
*kdb_modules
= &modules
; /* kdb needs the list of modules */
253 #endif /* CONFIG_KGDB_KDB */
255 static void module_assert_mutex(void)
257 lockdep_assert_held(&module_mutex
);
260 static void module_assert_mutex_or_preempt(void)
262 #ifdef CONFIG_LOCKDEP
263 if (unlikely(!debug_locks
))
266 WARN_ON(!rcu_read_lock_sched_held() &&
267 !lockdep_is_held(&module_mutex
));
271 static bool sig_enforce
= IS_ENABLED(CONFIG_MODULE_SIG_FORCE
);
272 #ifndef CONFIG_MODULE_SIG_FORCE
273 module_param(sig_enforce
, bool_enable_only
, 0644);
274 #endif /* !CONFIG_MODULE_SIG_FORCE */
276 /* Block module loading/unloading? */
277 int modules_disabled
= 0;
278 core_param(nomodule
, modules_disabled
, bint
, 0);
280 /* Waiting for a module to finish initializing? */
281 static DECLARE_WAIT_QUEUE_HEAD(module_wq
);
283 static BLOCKING_NOTIFIER_HEAD(module_notify_list
);
285 int register_module_notifier(struct notifier_block
*nb
)
287 return blocking_notifier_chain_register(&module_notify_list
, nb
);
289 EXPORT_SYMBOL(register_module_notifier
);
291 int unregister_module_notifier(struct notifier_block
*nb
)
293 return blocking_notifier_chain_unregister(&module_notify_list
, nb
);
295 EXPORT_SYMBOL(unregister_module_notifier
);
301 char *secstrings
, *strtab
;
302 unsigned long symoffs
, stroffs
;
303 struct _ddebug
*debug
;
304 unsigned int num_debug
;
307 unsigned int sym
, str
, mod
, vers
, info
, pcpu
;
311 /* We require a truly strong try_module_get(): 0 means failure due to
312 ongoing or failed initialization etc. */
313 static inline int strong_try_module_get(struct module
*mod
)
315 BUG_ON(mod
&& mod
->state
== MODULE_STATE_UNFORMED
);
316 if (mod
&& mod
->state
== MODULE_STATE_COMING
)
318 if (try_module_get(mod
))
324 static inline void add_taint_module(struct module
*mod
, unsigned flag
,
325 enum lockdep_ok lockdep_ok
)
327 add_taint(flag
, lockdep_ok
);
328 mod
->taints
|= (1U << flag
);
332 * A thread that wants to hold a reference to a module only while it
333 * is running can call this to safely exit. nfsd and lockd use this.
335 void __module_put_and_exit(struct module
*mod
, long code
)
340 EXPORT_SYMBOL(__module_put_and_exit
);
342 /* Find a module section: 0 means not found. */
343 static unsigned int find_sec(const struct load_info
*info
, const char *name
)
347 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
348 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
349 /* Alloc bit cleared means "ignore it." */
350 if ((shdr
->sh_flags
& SHF_ALLOC
)
351 && strcmp(info
->secstrings
+ shdr
->sh_name
, name
) == 0)
357 /* Find a module section, or NULL. */
358 static void *section_addr(const struct load_info
*info
, const char *name
)
360 /* Section 0 has sh_addr 0. */
361 return (void *)info
->sechdrs
[find_sec(info
, name
)].sh_addr
;
364 /* Find a module section, or NULL. Fill in number of "objects" in section. */
365 static void *section_objs(const struct load_info
*info
,
370 unsigned int sec
= find_sec(info
, name
);
372 /* Section 0 has sh_addr 0 and sh_size 0. */
373 *num
= info
->sechdrs
[sec
].sh_size
/ object_size
;
374 return (void *)info
->sechdrs
[sec
].sh_addr
;
377 /* Provided by the linker */
378 extern const struct kernel_symbol __start___ksymtab
[];
379 extern const struct kernel_symbol __stop___ksymtab
[];
380 extern const struct kernel_symbol __start___ksymtab_gpl
[];
381 extern const struct kernel_symbol __stop___ksymtab_gpl
[];
382 extern const struct kernel_symbol __start___ksymtab_gpl_future
[];
383 extern const struct kernel_symbol __stop___ksymtab_gpl_future
[];
384 extern const unsigned long __start___kcrctab
[];
385 extern const unsigned long __start___kcrctab_gpl
[];
386 extern const unsigned long __start___kcrctab_gpl_future
[];
387 #ifdef CONFIG_UNUSED_SYMBOLS
388 extern const struct kernel_symbol __start___ksymtab_unused
[];
389 extern const struct kernel_symbol __stop___ksymtab_unused
[];
390 extern const struct kernel_symbol __start___ksymtab_unused_gpl
[];
391 extern const struct kernel_symbol __stop___ksymtab_unused_gpl
[];
392 extern const unsigned long __start___kcrctab_unused
[];
393 extern const unsigned long __start___kcrctab_unused_gpl
[];
396 #ifndef CONFIG_MODVERSIONS
397 #define symversion(base, idx) NULL
399 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
402 static bool each_symbol_in_section(const struct symsearch
*arr
,
403 unsigned int arrsize
,
404 struct module
*owner
,
405 bool (*fn
)(const struct symsearch
*syms
,
406 struct module
*owner
,
412 for (j
= 0; j
< arrsize
; j
++) {
413 if (fn(&arr
[j
], owner
, data
))
420 /* Returns true as soon as fn returns true, otherwise false. */
421 bool each_symbol_section(bool (*fn
)(const struct symsearch
*arr
,
422 struct module
*owner
,
427 static const struct symsearch arr
[] = {
428 { __start___ksymtab
, __stop___ksymtab
, __start___kcrctab
,
429 NOT_GPL_ONLY
, false },
430 { __start___ksymtab_gpl
, __stop___ksymtab_gpl
,
431 __start___kcrctab_gpl
,
433 { __start___ksymtab_gpl_future
, __stop___ksymtab_gpl_future
,
434 __start___kcrctab_gpl_future
,
435 WILL_BE_GPL_ONLY
, false },
436 #ifdef CONFIG_UNUSED_SYMBOLS
437 { __start___ksymtab_unused
, __stop___ksymtab_unused
,
438 __start___kcrctab_unused
,
439 NOT_GPL_ONLY
, true },
440 { __start___ksymtab_unused_gpl
, __stop___ksymtab_unused_gpl
,
441 __start___kcrctab_unused_gpl
,
446 module_assert_mutex_or_preempt();
448 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), NULL
, fn
, data
))
451 list_for_each_entry_rcu(mod
, &modules
, list
) {
452 struct symsearch arr
[] = {
453 { mod
->syms
, mod
->syms
+ mod
->num_syms
, mod
->crcs
,
454 NOT_GPL_ONLY
, false },
455 { mod
->gpl_syms
, mod
->gpl_syms
+ mod
->num_gpl_syms
,
458 { mod
->gpl_future_syms
,
459 mod
->gpl_future_syms
+ mod
->num_gpl_future_syms
,
460 mod
->gpl_future_crcs
,
461 WILL_BE_GPL_ONLY
, false },
462 #ifdef CONFIG_UNUSED_SYMBOLS
464 mod
->unused_syms
+ mod
->num_unused_syms
,
466 NOT_GPL_ONLY
, true },
467 { mod
->unused_gpl_syms
,
468 mod
->unused_gpl_syms
+ mod
->num_unused_gpl_syms
,
469 mod
->unused_gpl_crcs
,
474 if (mod
->state
== MODULE_STATE_UNFORMED
)
477 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), mod
, fn
, data
))
482 EXPORT_SYMBOL_GPL(each_symbol_section
);
484 struct find_symbol_arg
{
491 struct module
*owner
;
492 const unsigned long *crc
;
493 const struct kernel_symbol
*sym
;
496 static bool check_symbol(const struct symsearch
*syms
,
497 struct module
*owner
,
498 unsigned int symnum
, void *data
)
500 struct find_symbol_arg
*fsa
= data
;
503 if (syms
->licence
== GPL_ONLY
)
505 if (syms
->licence
== WILL_BE_GPL_ONLY
&& fsa
->warn
) {
506 pr_warn("Symbol %s is being used by a non-GPL module, "
507 "which will not be allowed in the future\n",
512 #ifdef CONFIG_UNUSED_SYMBOLS
513 if (syms
->unused
&& fsa
->warn
) {
514 pr_warn("Symbol %s is marked as UNUSED, however this module is "
515 "using it.\n", fsa
->name
);
516 pr_warn("This symbol will go away in the future.\n");
517 pr_warn("Please evaluate if this is the right api to use and "
518 "if it really is, submit a report to the linux kernel "
519 "mailing list together with submitting your code for "
525 fsa
->crc
= symversion(syms
->crcs
, symnum
);
526 fsa
->sym
= &syms
->start
[symnum
];
530 static int cmp_name(const void *va
, const void *vb
)
533 const struct kernel_symbol
*b
;
535 return strcmp(a
, b
->name
);
538 static bool find_symbol_in_section(const struct symsearch
*syms
,
539 struct module
*owner
,
542 struct find_symbol_arg
*fsa
= data
;
543 struct kernel_symbol
*sym
;
545 sym
= bsearch(fsa
->name
, syms
->start
, syms
->stop
- syms
->start
,
546 sizeof(struct kernel_symbol
), cmp_name
);
548 if (sym
!= NULL
&& check_symbol(syms
, owner
, sym
- syms
->start
, data
))
554 /* Find a symbol and return it, along with, (optional) crc and
555 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
556 const struct kernel_symbol
*find_symbol(const char *name
,
557 struct module
**owner
,
558 const unsigned long **crc
,
562 struct find_symbol_arg fsa
;
568 if (each_symbol_section(find_symbol_in_section
, &fsa
)) {
576 pr_debug("Failed to find symbol %s\n", name
);
579 EXPORT_SYMBOL_GPL(find_symbol
);
582 * Search for module by name: must hold module_mutex (or preempt disabled
583 * for read-only access).
585 static struct module
*find_module_all(const char *name
, size_t len
,
590 module_assert_mutex_or_preempt();
592 list_for_each_entry(mod
, &modules
, list
) {
593 if (!even_unformed
&& mod
->state
== MODULE_STATE_UNFORMED
)
595 if (strlen(mod
->name
) == len
&& !memcmp(mod
->name
, name
, len
))
601 struct module
*find_module(const char *name
)
603 module_assert_mutex();
604 return find_module_all(name
, strlen(name
), false);
606 EXPORT_SYMBOL_GPL(find_module
);
610 static inline void __percpu
*mod_percpu(struct module
*mod
)
615 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
617 Elf_Shdr
*pcpusec
= &info
->sechdrs
[info
->index
.pcpu
];
618 unsigned long align
= pcpusec
->sh_addralign
;
620 if (!pcpusec
->sh_size
)
623 if (align
> PAGE_SIZE
) {
624 pr_warn("%s: per-cpu alignment %li > %li\n",
625 mod
->name
, align
, PAGE_SIZE
);
629 mod
->percpu
= __alloc_reserved_percpu(pcpusec
->sh_size
, align
);
631 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
632 mod
->name
, (unsigned long)pcpusec
->sh_size
);
635 mod
->percpu_size
= pcpusec
->sh_size
;
639 static void percpu_modfree(struct module
*mod
)
641 free_percpu(mod
->percpu
);
644 static unsigned int find_pcpusec(struct load_info
*info
)
646 return find_sec(info
, ".data..percpu");
649 static void percpu_modcopy(struct module
*mod
,
650 const void *from
, unsigned long size
)
654 for_each_possible_cpu(cpu
)
655 memcpy(per_cpu_ptr(mod
->percpu
, cpu
), from
, size
);
659 * is_module_percpu_address - test whether address is from module static percpu
660 * @addr: address to test
662 * Test whether @addr belongs to module static percpu area.
665 * %true if @addr is from module static percpu area
667 bool is_module_percpu_address(unsigned long addr
)
674 list_for_each_entry_rcu(mod
, &modules
, list
) {
675 if (mod
->state
== MODULE_STATE_UNFORMED
)
677 if (!mod
->percpu_size
)
679 for_each_possible_cpu(cpu
) {
680 void *start
= per_cpu_ptr(mod
->percpu
, cpu
);
682 if ((void *)addr
>= start
&&
683 (void *)addr
< start
+ mod
->percpu_size
) {
694 #else /* ... !CONFIG_SMP */
696 static inline void __percpu
*mod_percpu(struct module
*mod
)
700 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
702 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
703 if (info
->sechdrs
[info
->index
.pcpu
].sh_size
!= 0)
707 static inline void percpu_modfree(struct module
*mod
)
710 static unsigned int find_pcpusec(struct load_info
*info
)
714 static inline void percpu_modcopy(struct module
*mod
,
715 const void *from
, unsigned long size
)
717 /* pcpusec should be 0, and size of that section should be 0. */
720 bool is_module_percpu_address(unsigned long addr
)
725 #endif /* CONFIG_SMP */
727 #define MODINFO_ATTR(field) \
728 static void setup_modinfo_##field(struct module *mod, const char *s) \
730 mod->field = kstrdup(s, GFP_KERNEL); \
732 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
733 struct module_kobject *mk, char *buffer) \
735 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
737 static int modinfo_##field##_exists(struct module *mod) \
739 return mod->field != NULL; \
741 static void free_modinfo_##field(struct module *mod) \
746 static struct module_attribute modinfo_##field = { \
747 .attr = { .name = __stringify(field), .mode = 0444 }, \
748 .show = show_modinfo_##field, \
749 .setup = setup_modinfo_##field, \
750 .test = modinfo_##field##_exists, \
751 .free = free_modinfo_##field, \
754 MODINFO_ATTR(version
);
755 MODINFO_ATTR(srcversion
);
757 static char last_unloaded_module
[MODULE_NAME_LEN
+1];
759 #ifdef CONFIG_MODULE_UNLOAD
761 EXPORT_TRACEPOINT_SYMBOL(module_get
);
763 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
764 #define MODULE_REF_BASE 1
766 /* Init the unload section of the module. */
767 static int module_unload_init(struct module
*mod
)
770 * Initialize reference counter to MODULE_REF_BASE.
771 * refcnt == 0 means module is going.
773 atomic_set(&mod
->refcnt
, MODULE_REF_BASE
);
775 INIT_LIST_HEAD(&mod
->source_list
);
776 INIT_LIST_HEAD(&mod
->target_list
);
778 /* Hold reference count during initialization. */
779 atomic_inc(&mod
->refcnt
);
784 /* Does a already use b? */
785 static int already_uses(struct module
*a
, struct module
*b
)
787 struct module_use
*use
;
789 list_for_each_entry(use
, &b
->source_list
, source_list
) {
790 if (use
->source
== a
) {
791 pr_debug("%s uses %s!\n", a
->name
, b
->name
);
795 pr_debug("%s does not use %s!\n", a
->name
, b
->name
);
801 * - we add 'a' as a "source", 'b' as a "target" of module use
802 * - the module_use is added to the list of 'b' sources (so
803 * 'b' can walk the list to see who sourced them), and of 'a'
804 * targets (so 'a' can see what modules it targets).
806 static int add_module_usage(struct module
*a
, struct module
*b
)
808 struct module_use
*use
;
810 pr_debug("Allocating new usage for %s.\n", a
->name
);
811 use
= kmalloc(sizeof(*use
), GFP_ATOMIC
);
813 pr_warn("%s: out of memory loading\n", a
->name
);
819 list_add(&use
->source_list
, &b
->source_list
);
820 list_add(&use
->target_list
, &a
->target_list
);
824 /* Module a uses b: caller needs module_mutex() */
825 int ref_module(struct module
*a
, struct module
*b
)
829 if (b
== NULL
|| already_uses(a
, b
))
832 /* If module isn't available, we fail. */
833 err
= strong_try_module_get(b
);
837 err
= add_module_usage(a
, b
);
844 EXPORT_SYMBOL_GPL(ref_module
);
846 /* Clear the unload stuff of the module. */
847 static void module_unload_free(struct module
*mod
)
849 struct module_use
*use
, *tmp
;
851 mutex_lock(&module_mutex
);
852 list_for_each_entry_safe(use
, tmp
, &mod
->target_list
, target_list
) {
853 struct module
*i
= use
->target
;
854 pr_debug("%s unusing %s\n", mod
->name
, i
->name
);
856 list_del(&use
->source_list
);
857 list_del(&use
->target_list
);
860 mutex_unlock(&module_mutex
);
863 #ifdef CONFIG_MODULE_FORCE_UNLOAD
864 static inline int try_force_unload(unsigned int flags
)
866 int ret
= (flags
& O_TRUNC
);
868 add_taint(TAINT_FORCED_RMMOD
, LOCKDEP_NOW_UNRELIABLE
);
872 static inline int try_force_unload(unsigned int flags
)
876 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
878 /* Try to release refcount of module, 0 means success. */
879 static int try_release_module_ref(struct module
*mod
)
883 /* Try to decrement refcnt which we set at loading */
884 ret
= atomic_sub_return(MODULE_REF_BASE
, &mod
->refcnt
);
887 /* Someone can put this right now, recover with checking */
888 ret
= atomic_add_unless(&mod
->refcnt
, MODULE_REF_BASE
, 0);
893 static int try_stop_module(struct module
*mod
, int flags
, int *forced
)
895 /* If it's not unused, quit unless we're forcing. */
896 if (try_release_module_ref(mod
) != 0) {
897 *forced
= try_force_unload(flags
);
902 /* Mark it as dying. */
903 mod
->state
= MODULE_STATE_GOING
;
909 * module_refcount - return the refcount or -1 if unloading
911 * @mod: the module we're checking
914 * -1 if the module is in the process of unloading
915 * otherwise the number of references in the kernel to the module
917 int module_refcount(struct module
*mod
)
919 return atomic_read(&mod
->refcnt
) - MODULE_REF_BASE
;
921 EXPORT_SYMBOL(module_refcount
);
923 /* This exists whether we can unload or not */
924 static void free_module(struct module
*mod
);
926 SYSCALL_DEFINE2(delete_module
, const char __user
*, name_user
,
930 char name
[MODULE_NAME_LEN
];
933 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
936 if (strncpy_from_user(name
, name_user
, MODULE_NAME_LEN
-1) < 0)
938 name
[MODULE_NAME_LEN
-1] = '\0';
940 if (mutex_lock_interruptible(&module_mutex
) != 0)
943 mod
= find_module(name
);
949 if (!list_empty(&mod
->source_list
)) {
950 /* Other modules depend on us: get rid of them first. */
955 /* Doing init or already dying? */
956 if (mod
->state
!= MODULE_STATE_LIVE
) {
957 /* FIXME: if (force), slam module count damn the torpedoes */
958 pr_debug("%s already dying\n", mod
->name
);
963 /* If it has an init func, it must have an exit func to unload */
964 if (mod
->init
&& !mod
->exit
) {
965 forced
= try_force_unload(flags
);
967 /* This module can't be removed */
973 /* Stop the machine so refcounts can't move and disable module. */
974 ret
= try_stop_module(mod
, flags
, &forced
);
978 mutex_unlock(&module_mutex
);
979 /* Final destruction now no one is using it. */
980 if (mod
->exit
!= NULL
)
982 blocking_notifier_call_chain(&module_notify_list
,
983 MODULE_STATE_GOING
, mod
);
984 async_synchronize_full();
986 /* Store the name of the last unloaded module for diagnostic purposes */
987 strlcpy(last_unloaded_module
, mod
->name
, sizeof(last_unloaded_module
));
992 mutex_unlock(&module_mutex
);
996 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
998 struct module_use
*use
;
999 int printed_something
= 0;
1001 seq_printf(m
, " %i ", module_refcount(mod
));
1004 * Always include a trailing , so userspace can differentiate
1005 * between this and the old multi-field proc format.
1007 list_for_each_entry(use
, &mod
->source_list
, source_list
) {
1008 printed_something
= 1;
1009 seq_printf(m
, "%s,", use
->source
->name
);
1012 if (mod
->init
!= NULL
&& mod
->exit
== NULL
) {
1013 printed_something
= 1;
1014 seq_puts(m
, "[permanent],");
1017 if (!printed_something
)
1021 void __symbol_put(const char *symbol
)
1023 struct module
*owner
;
1026 if (!find_symbol(symbol
, &owner
, NULL
, true, false))
1031 EXPORT_SYMBOL(__symbol_put
);
1033 /* Note this assumes addr is a function, which it currently always is. */
1034 void symbol_put_addr(void *addr
)
1036 struct module
*modaddr
;
1037 unsigned long a
= (unsigned long)dereference_function_descriptor(addr
);
1039 if (core_kernel_text(a
))
1043 * Even though we hold a reference on the module; we still need to
1044 * disable preemption in order to safely traverse the data structure.
1047 modaddr
= __module_text_address(a
);
1049 module_put(modaddr
);
1052 EXPORT_SYMBOL_GPL(symbol_put_addr
);
1054 static ssize_t
show_refcnt(struct module_attribute
*mattr
,
1055 struct module_kobject
*mk
, char *buffer
)
1057 return sprintf(buffer
, "%i\n", module_refcount(mk
->mod
));
1060 static struct module_attribute modinfo_refcnt
=
1061 __ATTR(refcnt
, 0444, show_refcnt
, NULL
);
1063 void __module_get(struct module
*module
)
1067 atomic_inc(&module
->refcnt
);
1068 trace_module_get(module
, _RET_IP_
);
1072 EXPORT_SYMBOL(__module_get
);
1074 bool try_module_get(struct module
*module
)
1080 /* Note: here, we can fail to get a reference */
1081 if (likely(module_is_live(module
) &&
1082 atomic_inc_not_zero(&module
->refcnt
) != 0))
1083 trace_module_get(module
, _RET_IP_
);
1091 EXPORT_SYMBOL(try_module_get
);
1093 void module_put(struct module
*module
)
1099 ret
= atomic_dec_if_positive(&module
->refcnt
);
1100 WARN_ON(ret
< 0); /* Failed to put refcount */
1101 trace_module_put(module
, _RET_IP_
);
1105 EXPORT_SYMBOL(module_put
);
1107 #else /* !CONFIG_MODULE_UNLOAD */
1108 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1110 /* We don't know the usage count, or what modules are using. */
1111 seq_puts(m
, " - -");
1114 static inline void module_unload_free(struct module
*mod
)
1118 int ref_module(struct module
*a
, struct module
*b
)
1120 return strong_try_module_get(b
);
1122 EXPORT_SYMBOL_GPL(ref_module
);
1124 static inline int module_unload_init(struct module
*mod
)
1128 #endif /* CONFIG_MODULE_UNLOAD */
1130 static size_t module_flags_taint(struct module
*mod
, char *buf
)
1134 if (mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
))
1136 if (mod
->taints
& (1 << TAINT_OOT_MODULE
))
1138 if (mod
->taints
& (1 << TAINT_FORCED_MODULE
))
1140 if (mod
->taints
& (1 << TAINT_CRAP
))
1142 if (mod
->taints
& (1 << TAINT_UNSIGNED_MODULE
))
1145 * TAINT_FORCED_RMMOD: could be added.
1146 * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
1152 static ssize_t
show_initstate(struct module_attribute
*mattr
,
1153 struct module_kobject
*mk
, char *buffer
)
1155 const char *state
= "unknown";
1157 switch (mk
->mod
->state
) {
1158 case MODULE_STATE_LIVE
:
1161 case MODULE_STATE_COMING
:
1164 case MODULE_STATE_GOING
:
1170 return sprintf(buffer
, "%s\n", state
);
1173 static struct module_attribute modinfo_initstate
=
1174 __ATTR(initstate
, 0444, show_initstate
, NULL
);
1176 static ssize_t
store_uevent(struct module_attribute
*mattr
,
1177 struct module_kobject
*mk
,
1178 const char *buffer
, size_t count
)
1180 enum kobject_action action
;
1182 if (kobject_action_type(buffer
, count
, &action
) == 0)
1183 kobject_uevent(&mk
->kobj
, action
);
1187 struct module_attribute module_uevent
=
1188 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1190 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1191 struct module_kobject
*mk
, char *buffer
)
1193 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1196 static struct module_attribute modinfo_coresize
=
1197 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1199 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1200 struct module_kobject
*mk
, char *buffer
)
1202 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1205 static struct module_attribute modinfo_initsize
=
1206 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1208 static ssize_t
show_taint(struct module_attribute
*mattr
,
1209 struct module_kobject
*mk
, char *buffer
)
1213 l
= module_flags_taint(mk
->mod
, buffer
);
1218 static struct module_attribute modinfo_taint
=
1219 __ATTR(taint
, 0444, show_taint
, NULL
);
1221 static struct module_attribute
*modinfo_attrs
[] = {
1224 &modinfo_srcversion
,
1229 #ifdef CONFIG_MODULE_UNLOAD
1235 static const char vermagic
[] = VERMAGIC_STRING
;
1237 static int try_to_force_load(struct module
*mod
, const char *reason
)
1239 #ifdef CONFIG_MODULE_FORCE_LOAD
1240 if (!test_taint(TAINT_FORCED_MODULE
))
1241 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1242 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1249 #ifdef CONFIG_MODVERSIONS
1250 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
1251 static unsigned long maybe_relocated(unsigned long crc
,
1252 const struct module
*crc_owner
)
1254 #ifdef ARCH_RELOCATES_KCRCTAB
1255 if (crc_owner
== NULL
)
1256 return crc
- (unsigned long)reloc_start
;
1261 static int check_version(Elf_Shdr
*sechdrs
,
1262 unsigned int versindex
,
1263 const char *symname
,
1265 const unsigned long *crc
,
1266 const struct module
*crc_owner
)
1268 unsigned int i
, num_versions
;
1269 struct modversion_info
*versions
;
1271 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1275 /* No versions at all? modprobe --force does this. */
1277 return try_to_force_load(mod
, symname
) == 0;
1279 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1280 num_versions
= sechdrs
[versindex
].sh_size
1281 / sizeof(struct modversion_info
);
1283 for (i
= 0; i
< num_versions
; i
++) {
1284 if (strcmp(versions
[i
].name
, symname
) != 0)
1287 if (versions
[i
].crc
== maybe_relocated(*crc
, crc_owner
))
1289 pr_debug("Found checksum %lX vs module %lX\n",
1290 maybe_relocated(*crc
, crc_owner
), versions
[i
].crc
);
1294 pr_warn("%s: no symbol version for %s\n", mod
->name
, symname
);
1298 pr_warn("%s: disagrees about version of symbol %s\n",
1299 mod
->name
, symname
);
1303 static inline int check_modstruct_version(Elf_Shdr
*sechdrs
,
1304 unsigned int versindex
,
1307 const unsigned long *crc
;
1310 * Since this should be found in kernel (which can't be removed), no
1311 * locking is necessary -- use preempt_disable() to placate lockdep.
1314 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout
), NULL
,
1315 &crc
, true, false)) {
1320 return check_version(sechdrs
, versindex
,
1321 VMLINUX_SYMBOL_STR(module_layout
), mod
, crc
,
1325 /* First part is kernel version, which we ignore if module has crcs. */
1326 static inline int same_magic(const char *amagic
, const char *bmagic
,
1330 amagic
+= strcspn(amagic
, " ");
1331 bmagic
+= strcspn(bmagic
, " ");
1333 return strcmp(amagic
, bmagic
) == 0;
1336 static inline int check_version(Elf_Shdr
*sechdrs
,
1337 unsigned int versindex
,
1338 const char *symname
,
1340 const unsigned long *crc
,
1341 const struct module
*crc_owner
)
1346 static inline int check_modstruct_version(Elf_Shdr
*sechdrs
,
1347 unsigned int versindex
,
1353 static inline int same_magic(const char *amagic
, const char *bmagic
,
1356 return strcmp(amagic
, bmagic
) == 0;
1358 #endif /* CONFIG_MODVERSIONS */
1360 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1361 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1362 const struct load_info
*info
,
1366 struct module
*owner
;
1367 const struct kernel_symbol
*sym
;
1368 const unsigned long *crc
;
1372 * The module_mutex should not be a heavily contended lock;
1373 * if we get the occasional sleep here, we'll go an extra iteration
1374 * in the wait_event_interruptible(), which is harmless.
1376 sched_annotate_sleep();
1377 mutex_lock(&module_mutex
);
1378 sym
= find_symbol(name
, &owner
, &crc
,
1379 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1383 if (!check_version(info
->sechdrs
, info
->index
.vers
, name
, mod
, crc
,
1385 sym
= ERR_PTR(-EINVAL
);
1389 err
= ref_module(mod
, owner
);
1396 /* We must make copy under the lock if we failed to get ref. */
1397 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1399 mutex_unlock(&module_mutex
);
1403 static const struct kernel_symbol
*
1404 resolve_symbol_wait(struct module
*mod
,
1405 const struct load_info
*info
,
1408 const struct kernel_symbol
*ksym
;
1409 char owner
[MODULE_NAME_LEN
];
1411 if (wait_event_interruptible_timeout(module_wq
,
1412 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1413 || PTR_ERR(ksym
) != -EBUSY
,
1415 pr_warn("%s: gave up waiting for init of module %s.\n",
1422 * /sys/module/foo/sections stuff
1423 * J. Corbet <corbet@lwn.net>
1427 #ifdef CONFIG_KALLSYMS
1428 static inline bool sect_empty(const Elf_Shdr
*sect
)
1430 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1433 struct module_sect_attr
{
1434 struct module_attribute mattr
;
1436 unsigned long address
;
1439 struct module_sect_attrs
{
1440 struct attribute_group grp
;
1441 unsigned int nsections
;
1442 struct module_sect_attr attrs
[0];
1445 static ssize_t
module_sect_show(struct module_attribute
*mattr
,
1446 struct module_kobject
*mk
, char *buf
)
1448 struct module_sect_attr
*sattr
=
1449 container_of(mattr
, struct module_sect_attr
, mattr
);
1450 return sprintf(buf
, "0x%pK\n", (void *)sattr
->address
);
1453 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1455 unsigned int section
;
1457 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1458 kfree(sect_attrs
->attrs
[section
].name
);
1462 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1464 unsigned int nloaded
= 0, i
, size
[2];
1465 struct module_sect_attrs
*sect_attrs
;
1466 struct module_sect_attr
*sattr
;
1467 struct attribute
**gattr
;
1469 /* Count loaded sections and allocate structures */
1470 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1471 if (!sect_empty(&info
->sechdrs
[i
]))
1473 size
[0] = ALIGN(sizeof(*sect_attrs
)
1474 + nloaded
* sizeof(sect_attrs
->attrs
[0]),
1475 sizeof(sect_attrs
->grp
.attrs
[0]));
1476 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.attrs
[0]);
1477 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1478 if (sect_attrs
== NULL
)
1481 /* Setup section attributes. */
1482 sect_attrs
->grp
.name
= "sections";
1483 sect_attrs
->grp
.attrs
= (void *)sect_attrs
+ size
[0];
1485 sect_attrs
->nsections
= 0;
1486 sattr
= §_attrs
->attrs
[0];
1487 gattr
= §_attrs
->grp
.attrs
[0];
1488 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1489 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1490 if (sect_empty(sec
))
1492 sattr
->address
= sec
->sh_addr
;
1493 sattr
->name
= kstrdup(info
->secstrings
+ sec
->sh_name
,
1495 if (sattr
->name
== NULL
)
1497 sect_attrs
->nsections
++;
1498 sysfs_attr_init(&sattr
->mattr
.attr
);
1499 sattr
->mattr
.show
= module_sect_show
;
1500 sattr
->mattr
.store
= NULL
;
1501 sattr
->mattr
.attr
.name
= sattr
->name
;
1502 sattr
->mattr
.attr
.mode
= S_IRUGO
;
1503 *(gattr
++) = &(sattr
++)->mattr
.attr
;
1507 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1510 mod
->sect_attrs
= sect_attrs
;
1513 free_sect_attrs(sect_attrs
);
1516 static void remove_sect_attrs(struct module
*mod
)
1518 if (mod
->sect_attrs
) {
1519 sysfs_remove_group(&mod
->mkobj
.kobj
,
1520 &mod
->sect_attrs
->grp
);
1521 /* We are positive that no one is using any sect attrs
1522 * at this point. Deallocate immediately. */
1523 free_sect_attrs(mod
->sect_attrs
);
1524 mod
->sect_attrs
= NULL
;
1529 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1532 struct module_notes_attrs
{
1533 struct kobject
*dir
;
1535 struct bin_attribute attrs
[0];
1538 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1539 struct bin_attribute
*bin_attr
,
1540 char *buf
, loff_t pos
, size_t count
)
1543 * The caller checked the pos and count against our size.
1545 memcpy(buf
, bin_attr
->private + pos
, count
);
1549 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1552 if (notes_attrs
->dir
) {
1554 sysfs_remove_bin_file(notes_attrs
->dir
,
1555 ¬es_attrs
->attrs
[i
]);
1556 kobject_put(notes_attrs
->dir
);
1561 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1563 unsigned int notes
, loaded
, i
;
1564 struct module_notes_attrs
*notes_attrs
;
1565 struct bin_attribute
*nattr
;
1567 /* failed to create section attributes, so can't create notes */
1568 if (!mod
->sect_attrs
)
1571 /* Count notes sections and allocate structures. */
1573 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1574 if (!sect_empty(&info
->sechdrs
[i
]) &&
1575 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1581 notes_attrs
= kzalloc(sizeof(*notes_attrs
)
1582 + notes
* sizeof(notes_attrs
->attrs
[0]),
1584 if (notes_attrs
== NULL
)
1587 notes_attrs
->notes
= notes
;
1588 nattr
= ¬es_attrs
->attrs
[0];
1589 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1590 if (sect_empty(&info
->sechdrs
[i
]))
1592 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1593 sysfs_bin_attr_init(nattr
);
1594 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].name
;
1595 nattr
->attr
.mode
= S_IRUGO
;
1596 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1597 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1598 nattr
->read
= module_notes_read
;
1604 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1605 if (!notes_attrs
->dir
)
1608 for (i
= 0; i
< notes
; ++i
)
1609 if (sysfs_create_bin_file(notes_attrs
->dir
,
1610 ¬es_attrs
->attrs
[i
]))
1613 mod
->notes_attrs
= notes_attrs
;
1617 free_notes_attrs(notes_attrs
, i
);
1620 static void remove_notes_attrs(struct module
*mod
)
1622 if (mod
->notes_attrs
)
1623 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1628 static inline void add_sect_attrs(struct module
*mod
,
1629 const struct load_info
*info
)
1633 static inline void remove_sect_attrs(struct module
*mod
)
1637 static inline void add_notes_attrs(struct module
*mod
,
1638 const struct load_info
*info
)
1642 static inline void remove_notes_attrs(struct module
*mod
)
1645 #endif /* CONFIG_KALLSYMS */
1647 static void add_usage_links(struct module
*mod
)
1649 #ifdef CONFIG_MODULE_UNLOAD
1650 struct module_use
*use
;
1653 mutex_lock(&module_mutex
);
1654 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1655 nowarn
= sysfs_create_link(use
->target
->holders_dir
,
1656 &mod
->mkobj
.kobj
, mod
->name
);
1658 mutex_unlock(&module_mutex
);
1662 static void del_usage_links(struct module
*mod
)
1664 #ifdef CONFIG_MODULE_UNLOAD
1665 struct module_use
*use
;
1667 mutex_lock(&module_mutex
);
1668 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1669 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1670 mutex_unlock(&module_mutex
);
1674 static int module_add_modinfo_attrs(struct module
*mod
)
1676 struct module_attribute
*attr
;
1677 struct module_attribute
*temp_attr
;
1681 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1682 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1684 if (!mod
->modinfo_attrs
)
1687 temp_attr
= mod
->modinfo_attrs
;
1688 for (i
= 0; (attr
= modinfo_attrs
[i
]) && !error
; i
++) {
1690 (attr
->test
&& attr
->test(mod
))) {
1691 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1692 sysfs_attr_init(&temp_attr
->attr
);
1693 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1701 static void module_remove_modinfo_attrs(struct module
*mod
)
1703 struct module_attribute
*attr
;
1706 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1707 /* pick a field to test for end of list */
1708 if (!attr
->attr
.name
)
1710 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1714 kfree(mod
->modinfo_attrs
);
1717 static void mod_kobject_put(struct module
*mod
)
1719 DECLARE_COMPLETION_ONSTACK(c
);
1720 mod
->mkobj
.kobj_completion
= &c
;
1721 kobject_put(&mod
->mkobj
.kobj
);
1722 wait_for_completion(&c
);
1725 static int mod_sysfs_init(struct module
*mod
)
1728 struct kobject
*kobj
;
1730 if (!module_sysfs_initialized
) {
1731 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1736 kobj
= kset_find_obj(module_kset
, mod
->name
);
1738 pr_err("%s: module is already loaded\n", mod
->name
);
1744 mod
->mkobj
.mod
= mod
;
1746 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1747 mod
->mkobj
.kobj
.kset
= module_kset
;
1748 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1751 mod_kobject_put(mod
);
1753 /* delay uevent until full sysfs population */
1758 static int mod_sysfs_setup(struct module
*mod
,
1759 const struct load_info
*info
,
1760 struct kernel_param
*kparam
,
1761 unsigned int num_params
)
1765 err
= mod_sysfs_init(mod
);
1769 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1770 if (!mod
->holders_dir
) {
1775 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1777 goto out_unreg_holders
;
1779 err
= module_add_modinfo_attrs(mod
);
1781 goto out_unreg_param
;
1783 add_usage_links(mod
);
1784 add_sect_attrs(mod
, info
);
1785 add_notes_attrs(mod
, info
);
1787 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1791 module_param_sysfs_remove(mod
);
1793 kobject_put(mod
->holders_dir
);
1795 mod_kobject_put(mod
);
1800 static void mod_sysfs_fini(struct module
*mod
)
1802 remove_notes_attrs(mod
);
1803 remove_sect_attrs(mod
);
1804 mod_kobject_put(mod
);
1807 static void init_param_lock(struct module
*mod
)
1809 mutex_init(&mod
->param_lock
);
1811 #else /* !CONFIG_SYSFS */
1813 static int mod_sysfs_setup(struct module
*mod
,
1814 const struct load_info
*info
,
1815 struct kernel_param
*kparam
,
1816 unsigned int num_params
)
1821 static void mod_sysfs_fini(struct module
*mod
)
1825 static void module_remove_modinfo_attrs(struct module
*mod
)
1829 static void del_usage_links(struct module
*mod
)
1833 static void init_param_lock(struct module
*mod
)
1836 #endif /* CONFIG_SYSFS */
1838 static void mod_sysfs_teardown(struct module
*mod
)
1840 del_usage_links(mod
);
1841 module_remove_modinfo_attrs(mod
);
1842 module_param_sysfs_remove(mod
);
1843 kobject_put(mod
->mkobj
.drivers_dir
);
1844 kobject_put(mod
->holders_dir
);
1845 mod_sysfs_fini(mod
);
1848 #ifdef CONFIG_DEBUG_SET_MODULE_RONX
1850 * LKM RO/NX protection: protect module's text/ro-data
1851 * from modification and any data from execution.
1853 * General layout of module is:
1854 * [text] [read-only-data] [writable data]
1855 * text_size -----^ ^ ^
1856 * ro_size ------------------------| |
1857 * size -------------------------------------------|
1859 * These values are always page-aligned (as is base)
1861 static void frob_text(const struct module_layout
*layout
,
1862 int (*set_memory
)(unsigned long start
, int num_pages
))
1864 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1865 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1866 set_memory((unsigned long)layout
->base
,
1867 layout
->text_size
>> PAGE_SHIFT
);
1870 static void frob_rodata(const struct module_layout
*layout
,
1871 int (*set_memory
)(unsigned long start
, int num_pages
))
1873 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1874 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1875 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1876 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
1877 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
1880 static void frob_writable_data(const struct module_layout
*layout
,
1881 int (*set_memory
)(unsigned long start
, int num_pages
))
1883 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1884 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1885 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
1886 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
1887 (layout
->size
- layout
->ro_size
) >> PAGE_SHIFT
);
1890 /* livepatching wants to disable read-only so it can frob module. */
1891 void module_disable_ro(const struct module
*mod
)
1893 frob_text(&mod
->core_layout
, set_memory_rw
);
1894 frob_rodata(&mod
->core_layout
, set_memory_rw
);
1895 frob_text(&mod
->init_layout
, set_memory_rw
);
1896 frob_rodata(&mod
->init_layout
, set_memory_rw
);
1899 void module_enable_ro(const struct module
*mod
)
1901 frob_text(&mod
->core_layout
, set_memory_ro
);
1902 frob_rodata(&mod
->core_layout
, set_memory_ro
);
1903 frob_text(&mod
->init_layout
, set_memory_ro
);
1904 frob_rodata(&mod
->init_layout
, set_memory_ro
);
1907 static void module_enable_nx(const struct module
*mod
)
1909 frob_rodata(&mod
->core_layout
, set_memory_nx
);
1910 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
1911 frob_rodata(&mod
->init_layout
, set_memory_nx
);
1912 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
1915 static void module_disable_nx(const struct module
*mod
)
1917 frob_rodata(&mod
->core_layout
, set_memory_x
);
1918 frob_writable_data(&mod
->core_layout
, set_memory_x
);
1919 frob_rodata(&mod
->init_layout
, set_memory_x
);
1920 frob_writable_data(&mod
->init_layout
, set_memory_x
);
1923 /* Iterate through all modules and set each module's text as RW */
1924 void set_all_modules_text_rw(void)
1928 mutex_lock(&module_mutex
);
1929 list_for_each_entry_rcu(mod
, &modules
, list
) {
1930 if (mod
->state
== MODULE_STATE_UNFORMED
)
1933 frob_text(&mod
->core_layout
, set_memory_rw
);
1934 frob_text(&mod
->init_layout
, set_memory_rw
);
1936 mutex_unlock(&module_mutex
);
1939 /* Iterate through all modules and set each module's text as RO */
1940 void set_all_modules_text_ro(void)
1944 mutex_lock(&module_mutex
);
1945 list_for_each_entry_rcu(mod
, &modules
, list
) {
1946 if (mod
->state
== MODULE_STATE_UNFORMED
)
1949 frob_text(&mod
->core_layout
, set_memory_ro
);
1950 frob_text(&mod
->init_layout
, set_memory_ro
);
1952 mutex_unlock(&module_mutex
);
1955 static void disable_ro_nx(const struct module_layout
*layout
)
1957 frob_text(layout
, set_memory_rw
);
1958 frob_rodata(layout
, set_memory_rw
);
1959 frob_rodata(layout
, set_memory_x
);
1960 frob_writable_data(layout
, set_memory_x
);
1964 static void disable_ro_nx(const struct module_layout
*layout
) { }
1965 static void module_enable_nx(const struct module
*mod
) { }
1966 static void module_disable_nx(const struct module
*mod
) { }
1969 void __weak
module_memfree(void *module_region
)
1971 vfree(module_region
);
1974 void __weak
module_arch_cleanup(struct module
*mod
)
1978 void __weak
module_arch_freeing_init(struct module
*mod
)
1982 /* Free a module, remove from lists, etc. */
1983 static void free_module(struct module
*mod
)
1985 trace_module_free(mod
);
1987 mod_sysfs_teardown(mod
);
1989 /* We leave it in list to prevent duplicate loads, but make sure
1990 * that noone uses it while it's being deconstructed. */
1991 mutex_lock(&module_mutex
);
1992 mod
->state
= MODULE_STATE_UNFORMED
;
1993 mutex_unlock(&module_mutex
);
1995 /* Remove dynamic debug info */
1996 ddebug_remove_module(mod
->name
);
1998 /* Arch-specific cleanup. */
1999 module_arch_cleanup(mod
);
2001 /* Module unload stuff */
2002 module_unload_free(mod
);
2004 /* Free any allocated parameters. */
2005 destroy_params(mod
->kp
, mod
->num_kp
);
2007 /* Now we can delete it from the lists */
2008 mutex_lock(&module_mutex
);
2009 /* Unlink carefully: kallsyms could be walking list. */
2010 list_del_rcu(&mod
->list
);
2011 mod_tree_remove(mod
);
2012 /* Remove this module from bug list, this uses list_del_rcu */
2013 module_bug_cleanup(mod
);
2014 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2015 synchronize_sched();
2016 mutex_unlock(&module_mutex
);
2018 /* This may be empty, but that's OK */
2019 disable_ro_nx(&mod
->init_layout
);
2020 module_arch_freeing_init(mod
);
2021 module_memfree(mod
->init_layout
.base
);
2023 percpu_modfree(mod
);
2025 /* Free lock-classes; relies on the preceding sync_rcu(). */
2026 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2028 /* Finally, free the core (containing the module structure) */
2029 disable_ro_nx(&mod
->core_layout
);
2030 module_memfree(mod
->core_layout
.base
);
2033 update_protections(current
->mm
);
2037 void *__symbol_get(const char *symbol
)
2039 struct module
*owner
;
2040 const struct kernel_symbol
*sym
;
2043 sym
= find_symbol(symbol
, &owner
, NULL
, true, true);
2044 if (sym
&& strong_try_module_get(owner
))
2048 return sym
? (void *)sym
->value
: NULL
;
2050 EXPORT_SYMBOL_GPL(__symbol_get
);
2053 * Ensure that an exported symbol [global namespace] does not already exist
2054 * in the kernel or in some other module's exported symbol table.
2056 * You must hold the module_mutex.
2058 static int verify_export_symbols(struct module
*mod
)
2061 struct module
*owner
;
2062 const struct kernel_symbol
*s
;
2064 const struct kernel_symbol
*sym
;
2067 { mod
->syms
, mod
->num_syms
},
2068 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2069 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2070 #ifdef CONFIG_UNUSED_SYMBOLS
2071 { mod
->unused_syms
, mod
->num_unused_syms
},
2072 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2076 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2077 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2078 if (find_symbol(s
->name
, &owner
, NULL
, true, false)) {
2079 pr_err("%s: exports duplicate symbol %s"
2081 mod
->name
, s
->name
, module_name(owner
));
2089 /* Change all symbols so that st_value encodes the pointer directly. */
2090 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2092 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2093 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2094 unsigned long secbase
;
2097 const struct kernel_symbol
*ksym
;
2099 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2100 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2102 switch (sym
[i
].st_shndx
) {
2104 /* Ignore common symbols */
2105 if (!strncmp(name
, "__gnu_lto", 9))
2108 /* We compiled with -fno-common. These are not
2109 supposed to happen. */
2110 pr_debug("Common symbol: %s\n", name
);
2111 pr_warn("%s: please compile with -fno-common\n",
2117 /* Don't need to do anything */
2118 pr_debug("Absolute symbol: 0x%08lx\n",
2119 (long)sym
[i
].st_value
);
2123 ksym
= resolve_symbol_wait(mod
, info
, name
);
2124 /* Ok if resolved. */
2125 if (ksym
&& !IS_ERR(ksym
)) {
2126 sym
[i
].st_value
= ksym
->value
;
2131 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2134 pr_warn("%s: Unknown symbol %s (err %li)\n",
2135 mod
->name
, name
, PTR_ERR(ksym
));
2136 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2140 /* Divert to percpu allocation if a percpu var. */
2141 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2142 secbase
= (unsigned long)mod_percpu(mod
);
2144 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2145 sym
[i
].st_value
+= secbase
;
2153 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2158 /* Now do relocations. */
2159 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2160 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2162 /* Not a valid relocation section? */
2163 if (infosec
>= info
->hdr
->e_shnum
)
2166 /* Don't bother with non-allocated sections */
2167 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2170 if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2171 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2172 info
->index
.sym
, i
, mod
);
2173 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2174 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2175 info
->index
.sym
, i
, mod
);
2182 /* Additional bytes needed by arch in front of individual sections */
2183 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2184 unsigned int section
)
2186 /* default implementation just returns zero */
2190 /* Update size with this section: return offset. */
2191 static long get_offset(struct module
*mod
, unsigned int *size
,
2192 Elf_Shdr
*sechdr
, unsigned int section
)
2196 *size
+= arch_mod_section_prepend(mod
, section
);
2197 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2198 *size
= ret
+ sechdr
->sh_size
;
2202 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2203 might -- code, read-only data, read-write data, small data. Tally
2204 sizes, and place the offsets into sh_entsize fields: high bit means it
2206 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2208 static unsigned long const masks
[][2] = {
2209 /* NOTE: all executable code must be the first section
2210 * in this array; otherwise modify the text_size
2211 * finder in the two loops below */
2212 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2213 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2214 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2215 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2219 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2220 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2222 pr_debug("Core section allocation order:\n");
2223 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2224 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2225 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2226 const char *sname
= info
->secstrings
+ s
->sh_name
;
2228 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2229 || (s
->sh_flags
& masks
[m
][1])
2230 || s
->sh_entsize
!= ~0UL
2231 || strstarts(sname
, ".init"))
2233 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2234 pr_debug("\t%s\n", sname
);
2237 case 0: /* executable */
2238 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2239 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2241 case 1: /* RO: text and ro-data */
2242 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2243 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2245 case 3: /* whole core */
2246 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2251 pr_debug("Init section allocation order:\n");
2252 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2253 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2254 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2255 const char *sname
= info
->secstrings
+ s
->sh_name
;
2257 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2258 || (s
->sh_flags
& masks
[m
][1])
2259 || s
->sh_entsize
!= ~0UL
2260 || !strstarts(sname
, ".init"))
2262 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2263 | INIT_OFFSET_MASK
);
2264 pr_debug("\t%s\n", sname
);
2267 case 0: /* executable */
2268 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2269 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2271 case 1: /* RO: text and ro-data */
2272 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2273 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2275 case 3: /* whole init */
2276 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2282 static void set_license(struct module
*mod
, const char *license
)
2285 license
= "unspecified";
2287 if (!license_is_gpl_compatible(license
)) {
2288 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2289 pr_warn("%s: module license '%s' taints kernel.\n",
2290 mod
->name
, license
);
2291 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2292 LOCKDEP_NOW_UNRELIABLE
);
2296 /* Parse tag=value strings from .modinfo section */
2297 static char *next_string(char *string
, unsigned long *secsize
)
2299 /* Skip non-zero chars */
2302 if ((*secsize
)-- <= 1)
2306 /* Skip any zero padding. */
2307 while (!string
[0]) {
2309 if ((*secsize
)-- <= 1)
2315 static char *get_modinfo(struct load_info
*info
, const char *tag
)
2318 unsigned int taglen
= strlen(tag
);
2319 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2320 unsigned long size
= infosec
->sh_size
;
2322 for (p
= (char *)infosec
->sh_addr
; p
; p
= next_string(p
, &size
)) {
2323 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2324 return p
+ taglen
+ 1;
2329 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2331 struct module_attribute
*attr
;
2334 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2336 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2340 static void free_modinfo(struct module
*mod
)
2342 struct module_attribute
*attr
;
2345 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2351 #ifdef CONFIG_KALLSYMS
2353 /* lookup symbol in given range of kernel_symbols */
2354 static const struct kernel_symbol
*lookup_symbol(const char *name
,
2355 const struct kernel_symbol
*start
,
2356 const struct kernel_symbol
*stop
)
2358 return bsearch(name
, start
, stop
- start
,
2359 sizeof(struct kernel_symbol
), cmp_name
);
2362 static int is_exported(const char *name
, unsigned long value
,
2363 const struct module
*mod
)
2365 const struct kernel_symbol
*ks
;
2367 ks
= lookup_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2369 ks
= lookup_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2370 return ks
!= NULL
&& ks
->value
== value
;
2374 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2376 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2378 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2379 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2384 if (sym
->st_shndx
== SHN_UNDEF
)
2386 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2388 if (sym
->st_shndx
>= SHN_LORESERVE
)
2390 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2392 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2393 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2394 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2396 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2401 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2402 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2407 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2414 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2415 unsigned int shnum
, unsigned int pcpundx
)
2417 const Elf_Shdr
*sec
;
2419 if (src
->st_shndx
== SHN_UNDEF
2420 || src
->st_shndx
>= shnum
2424 #ifdef CONFIG_KALLSYMS_ALL
2425 if (src
->st_shndx
== pcpundx
)
2429 sec
= sechdrs
+ src
->st_shndx
;
2430 if (!(sec
->sh_flags
& SHF_ALLOC
)
2431 #ifndef CONFIG_KALLSYMS_ALL
2432 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2434 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2441 * We only allocate and copy the strings needed by the parts of symtab
2442 * we keep. This is simple, but has the effect of making multiple
2443 * copies of duplicates. We could be more sophisticated, see
2444 * linux-kernel thread starting with
2445 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2447 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2449 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2450 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2452 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2454 /* Put symbol section at end of init part of module. */
2455 symsect
->sh_flags
|= SHF_ALLOC
;
2456 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2457 info
->index
.sym
) | INIT_OFFSET_MASK
;
2458 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2460 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2461 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2463 /* Compute total space required for the core symbols' strtab. */
2464 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2466 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2467 info
->index
.pcpu
)) {
2468 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2473 /* Append room for core symbols at end of core part. */
2474 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2475 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2476 mod
->core_layout
.size
+= strtab_size
;
2477 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2479 /* Put string table section at end of init part of module. */
2480 strsect
->sh_flags
|= SHF_ALLOC
;
2481 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2482 info
->index
.str
) | INIT_OFFSET_MASK
;
2483 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2484 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2487 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2489 unsigned int i
, ndst
;
2493 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2495 mod
->symtab
= (void *)symsec
->sh_addr
;
2496 mod
->num_symtab
= symsec
->sh_size
/ sizeof(Elf_Sym
);
2497 /* Make sure we get permanent strtab: don't use info->strtab. */
2498 mod
->strtab
= (void *)info
->sechdrs
[info
->index
.str
].sh_addr
;
2500 /* Set types up while we still have access to sections. */
2501 for (i
= 0; i
< mod
->num_symtab
; i
++)
2502 mod
->symtab
[i
].st_info
= elf_type(&mod
->symtab
[i
], info
);
2504 mod
->core_symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2505 mod
->core_strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2507 for (ndst
= i
= 0; i
< mod
->num_symtab
; i
++) {
2509 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2510 info
->index
.pcpu
)) {
2512 dst
[ndst
++].st_name
= s
- mod
->core_strtab
;
2513 s
+= strlcpy(s
, &mod
->strtab
[src
[i
].st_name
],
2517 mod
->core_num_syms
= ndst
;
2520 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2524 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2527 #endif /* CONFIG_KALLSYMS */
2529 static void dynamic_debug_setup(struct _ddebug
*debug
, unsigned int num
)
2533 #ifdef CONFIG_DYNAMIC_DEBUG
2534 if (ddebug_add_module(debug
, num
, debug
->modname
))
2535 pr_err("dynamic debug error adding module: %s\n",
2540 static void dynamic_debug_remove(struct _ddebug
*debug
)
2543 ddebug_remove_module(debug
->modname
);
2546 void * __weak
module_alloc(unsigned long size
)
2548 return vmalloc_exec(size
);
2551 #ifdef CONFIG_DEBUG_KMEMLEAK
2552 static void kmemleak_load_module(const struct module
*mod
,
2553 const struct load_info
*info
)
2557 /* only scan the sections containing data */
2558 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2560 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2561 /* Scan all writable sections that's not executable */
2562 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2563 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2564 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2567 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2568 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2572 static inline void kmemleak_load_module(const struct module
*mod
,
2573 const struct load_info
*info
)
2578 #ifdef CONFIG_MODULE_SIG
2579 static int module_sig_check(struct load_info
*info
)
2582 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2583 const void *mod
= info
->hdr
;
2585 if (info
->len
> markerlen
&&
2586 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2587 /* We truncate the module to discard the signature */
2588 info
->len
-= markerlen
;
2589 err
= mod_verify_sig(mod
, &info
->len
);
2593 info
->sig_ok
= true;
2597 /* Not having a signature is only an error if we're strict. */
2598 if (err
== -ENOKEY
&& !sig_enforce
)
2603 #else /* !CONFIG_MODULE_SIG */
2604 static int module_sig_check(struct load_info
*info
)
2608 #endif /* !CONFIG_MODULE_SIG */
2610 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2611 static int elf_header_check(struct load_info
*info
)
2613 if (info
->len
< sizeof(*(info
->hdr
)))
2616 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2617 || info
->hdr
->e_type
!= ET_REL
2618 || !elf_check_arch(info
->hdr
)
2619 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2622 if (info
->hdr
->e_shoff
>= info
->len
2623 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2624 info
->len
- info
->hdr
->e_shoff
))
2630 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2632 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2635 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2637 if (copy_from_user(dst
, usrc
, n
) != 0)
2647 /* Sets info->hdr and info->len. */
2648 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
2649 struct load_info
*info
)
2654 if (info
->len
< sizeof(*(info
->hdr
)))
2657 err
= security_kernel_module_from_file(NULL
);
2661 /* Suck in entire file: we'll want most of it. */
2662 info
->hdr
= __vmalloc(info
->len
,
2663 GFP_KERNEL
| __GFP_HIGHMEM
| __GFP_NOWARN
, PAGE_KERNEL
);
2667 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
2675 /* Sets info->hdr and info->len. */
2676 static int copy_module_from_fd(int fd
, struct load_info
*info
)
2678 struct fd f
= fdget(fd
);
2687 err
= security_kernel_module_from_file(f
.file
);
2691 err
= vfs_getattr(&f
.file
->f_path
, &stat
);
2695 if (stat
.size
> INT_MAX
) {
2700 /* Don't hand 0 to vmalloc, it whines. */
2701 if (stat
.size
== 0) {
2706 info
->hdr
= vmalloc(stat
.size
);
2713 while (pos
< stat
.size
) {
2714 bytes
= kernel_read(f
.file
, pos
, (char *)(info
->hdr
) + pos
,
2732 static void free_copy(struct load_info
*info
)
2737 static int rewrite_section_headers(struct load_info
*info
, int flags
)
2741 /* This should always be true, but let's be sure. */
2742 info
->sechdrs
[0].sh_addr
= 0;
2744 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2745 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
2746 if (shdr
->sh_type
!= SHT_NOBITS
2747 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
2748 pr_err("Module len %lu truncated\n", info
->len
);
2752 /* Mark all sections sh_addr with their address in the
2754 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
2756 #ifndef CONFIG_MODULE_UNLOAD
2757 /* Don't load .exit sections */
2758 if (strstarts(info
->secstrings
+shdr
->sh_name
, ".exit"))
2759 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2763 /* Track but don't keep modinfo and version sections. */
2764 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
2765 info
->index
.vers
= 0; /* Pretend no __versions section! */
2767 info
->index
.vers
= find_sec(info
, "__versions");
2768 info
->index
.info
= find_sec(info
, ".modinfo");
2769 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2770 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2775 * Set up our basic convenience variables (pointers to section headers,
2776 * search for module section index etc), and do some basic section
2779 * Return the temporary module pointer (we'll replace it with the final
2780 * one when we move the module sections around).
2782 static struct module
*setup_load_info(struct load_info
*info
, int flags
)
2788 /* Set up the convenience variables */
2789 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
2790 info
->secstrings
= (void *)info
->hdr
2791 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
2793 err
= rewrite_section_headers(info
, flags
);
2795 return ERR_PTR(err
);
2797 /* Find internal symbols and strings. */
2798 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2799 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
2800 info
->index
.sym
= i
;
2801 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
2802 info
->strtab
= (char *)info
->hdr
2803 + info
->sechdrs
[info
->index
.str
].sh_offset
;
2808 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
2809 if (!info
->index
.mod
) {
2810 pr_warn("No module found in object\n");
2811 return ERR_PTR(-ENOEXEC
);
2813 /* This is temporary: point mod into copy of data. */
2814 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
2816 if (info
->index
.sym
== 0) {
2817 pr_warn("%s: module has no symbols (stripped?)\n", mod
->name
);
2818 return ERR_PTR(-ENOEXEC
);
2821 info
->index
.pcpu
= find_pcpusec(info
);
2823 /* Check module struct version now, before we try to use module. */
2824 if (!check_modstruct_version(info
->sechdrs
, info
->index
.vers
, mod
))
2825 return ERR_PTR(-ENOEXEC
);
2830 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
2832 const char *modmagic
= get_modinfo(info
, "vermagic");
2835 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
2838 /* This is allowed: modprobe --force will invalidate it. */
2840 err
= try_to_force_load(mod
, "bad vermagic");
2843 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
2844 pr_err("%s: version magic '%s' should be '%s'\n",
2845 mod
->name
, modmagic
, vermagic
);
2849 if (!get_modinfo(info
, "intree"))
2850 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
2852 if (get_modinfo(info
, "staging")) {
2853 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
2854 pr_warn("%s: module is from the staging directory, the quality "
2855 "is unknown, you have been warned.\n", mod
->name
);
2858 /* Set up license info based on the info section */
2859 set_license(mod
, get_modinfo(info
, "license"));
2864 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
2866 mod
->kp
= section_objs(info
, "__param",
2867 sizeof(*mod
->kp
), &mod
->num_kp
);
2868 mod
->syms
= section_objs(info
, "__ksymtab",
2869 sizeof(*mod
->syms
), &mod
->num_syms
);
2870 mod
->crcs
= section_addr(info
, "__kcrctab");
2871 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
2872 sizeof(*mod
->gpl_syms
),
2873 &mod
->num_gpl_syms
);
2874 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
2875 mod
->gpl_future_syms
= section_objs(info
,
2876 "__ksymtab_gpl_future",
2877 sizeof(*mod
->gpl_future_syms
),
2878 &mod
->num_gpl_future_syms
);
2879 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
2881 #ifdef CONFIG_UNUSED_SYMBOLS
2882 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
2883 sizeof(*mod
->unused_syms
),
2884 &mod
->num_unused_syms
);
2885 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
2886 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
2887 sizeof(*mod
->unused_gpl_syms
),
2888 &mod
->num_unused_gpl_syms
);
2889 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
2891 #ifdef CONFIG_CONSTRUCTORS
2892 mod
->ctors
= section_objs(info
, ".ctors",
2893 sizeof(*mod
->ctors
), &mod
->num_ctors
);
2895 mod
->ctors
= section_objs(info
, ".init_array",
2896 sizeof(*mod
->ctors
), &mod
->num_ctors
);
2897 else if (find_sec(info
, ".init_array")) {
2899 * This shouldn't happen with same compiler and binutils
2900 * building all parts of the module.
2902 pr_warn("%s: has both .ctors and .init_array.\n",
2908 #ifdef CONFIG_TRACEPOINTS
2909 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
2910 sizeof(*mod
->tracepoints_ptrs
),
2911 &mod
->num_tracepoints
);
2913 #ifdef HAVE_JUMP_LABEL
2914 mod
->jump_entries
= section_objs(info
, "__jump_table",
2915 sizeof(*mod
->jump_entries
),
2916 &mod
->num_jump_entries
);
2918 #ifdef CONFIG_EVENT_TRACING
2919 mod
->trace_events
= section_objs(info
, "_ftrace_events",
2920 sizeof(*mod
->trace_events
),
2921 &mod
->num_trace_events
);
2922 mod
->trace_enums
= section_objs(info
, "_ftrace_enum_map",
2923 sizeof(*mod
->trace_enums
),
2924 &mod
->num_trace_enums
);
2926 #ifdef CONFIG_TRACING
2927 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
2928 sizeof(*mod
->trace_bprintk_fmt_start
),
2929 &mod
->num_trace_bprintk_fmt
);
2931 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2932 /* sechdrs[0].sh_size is always zero */
2933 mod
->ftrace_callsites
= section_objs(info
, "__mcount_loc",
2934 sizeof(*mod
->ftrace_callsites
),
2935 &mod
->num_ftrace_callsites
);
2938 mod
->extable
= section_objs(info
, "__ex_table",
2939 sizeof(*mod
->extable
), &mod
->num_exentries
);
2941 if (section_addr(info
, "__obsparm"))
2942 pr_warn("%s: Ignoring obsolete parameters\n", mod
->name
);
2944 info
->debug
= section_objs(info
, "__verbose",
2945 sizeof(*info
->debug
), &info
->num_debug
);
2950 static int move_module(struct module
*mod
, struct load_info
*info
)
2955 /* Do the allocs. */
2956 ptr
= module_alloc(mod
->core_layout
.size
);
2958 * The pointer to this block is stored in the module structure
2959 * which is inside the block. Just mark it as not being a
2962 kmemleak_not_leak(ptr
);
2966 memset(ptr
, 0, mod
->core_layout
.size
);
2967 mod
->core_layout
.base
= ptr
;
2969 if (mod
->init_layout
.size
) {
2970 ptr
= module_alloc(mod
->init_layout
.size
);
2972 * The pointer to this block is stored in the module structure
2973 * which is inside the block. This block doesn't need to be
2974 * scanned as it contains data and code that will be freed
2975 * after the module is initialized.
2977 kmemleak_ignore(ptr
);
2979 module_memfree(mod
->core_layout
.base
);
2982 memset(ptr
, 0, mod
->init_layout
.size
);
2983 mod
->init_layout
.base
= ptr
;
2985 mod
->init_layout
.base
= NULL
;
2987 /* Transfer each section which specifies SHF_ALLOC */
2988 pr_debug("final section addresses:\n");
2989 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
2991 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
2993 if (!(shdr
->sh_flags
& SHF_ALLOC
))
2996 if (shdr
->sh_entsize
& INIT_OFFSET_MASK
)
2997 dest
= mod
->init_layout
.base
2998 + (shdr
->sh_entsize
& ~INIT_OFFSET_MASK
);
3000 dest
= mod
->core_layout
.base
+ shdr
->sh_entsize
;
3002 if (shdr
->sh_type
!= SHT_NOBITS
)
3003 memcpy(dest
, (void *)shdr
->sh_addr
, shdr
->sh_size
);
3004 /* Update sh_addr to point to copy in image. */
3005 shdr
->sh_addr
= (unsigned long)dest
;
3006 pr_debug("\t0x%lx %s\n",
3007 (long)shdr
->sh_addr
, info
->secstrings
+ shdr
->sh_name
);
3013 static int check_module_license_and_versions(struct module
*mod
)
3016 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3017 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3018 * using GPL-only symbols it needs.
3020 if (strcmp(mod
->name
, "ndiswrapper") == 0)
3021 add_taint(TAINT_PROPRIETARY_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
3023 /* driverloader was caught wrongly pretending to be under GPL */
3024 if (strcmp(mod
->name
, "driverloader") == 0)
3025 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3026 LOCKDEP_NOW_UNRELIABLE
);
3028 /* lve claims to be GPL but upstream won't provide source */
3029 if (strcmp(mod
->name
, "lve") == 0)
3030 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3031 LOCKDEP_NOW_UNRELIABLE
);
3033 #ifdef CONFIG_MODVERSIONS
3034 if ((mod
->num_syms
&& !mod
->crcs
)
3035 || (mod
->num_gpl_syms
&& !mod
->gpl_crcs
)
3036 || (mod
->num_gpl_future_syms
&& !mod
->gpl_future_crcs
)
3037 #ifdef CONFIG_UNUSED_SYMBOLS
3038 || (mod
->num_unused_syms
&& !mod
->unused_crcs
)
3039 || (mod
->num_unused_gpl_syms
&& !mod
->unused_gpl_crcs
)
3042 return try_to_force_load(mod
,
3043 "no versions for exported symbols");
3049 static void flush_module_icache(const struct module
*mod
)
3051 mm_segment_t old_fs
;
3053 /* flush the icache in correct context */
3058 * Flush the instruction cache, since we've played with text.
3059 * Do it before processing of module parameters, so the module
3060 * can provide parameter accessor functions of its own.
3062 if (mod
->init_layout
.base
)
3063 flush_icache_range((unsigned long)mod
->init_layout
.base
,
3064 (unsigned long)mod
->init_layout
.base
3065 + mod
->init_layout
.size
);
3066 flush_icache_range((unsigned long)mod
->core_layout
.base
,
3067 (unsigned long)mod
->core_layout
.base
+ mod
->core_layout
.size
);
3072 int __weak
module_frob_arch_sections(Elf_Ehdr
*hdr
,
3080 static struct module
*layout_and_allocate(struct load_info
*info
, int flags
)
3082 /* Module within temporary copy. */
3086 mod
= setup_load_info(info
, flags
);
3090 err
= check_modinfo(mod
, info
, flags
);
3092 return ERR_PTR(err
);
3094 /* Allow arches to frob section contents and sizes. */
3095 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3096 info
->secstrings
, mod
);
3098 return ERR_PTR(err
);
3100 /* We will do a special allocation for per-cpu sections later. */
3101 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3103 /* Determine total sizes, and put offsets in sh_entsize. For now
3104 this is done generically; there doesn't appear to be any
3105 special cases for the architectures. */
3106 layout_sections(mod
, info
);
3107 layout_symtab(mod
, info
);
3109 /* Allocate and move to the final place */
3110 err
= move_module(mod
, info
);
3112 return ERR_PTR(err
);
3114 /* Module has been copied to its final place now: return it. */
3115 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3116 kmemleak_load_module(mod
, info
);
3120 /* mod is no longer valid after this! */
3121 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3123 percpu_modfree(mod
);
3124 module_arch_freeing_init(mod
);
3125 module_memfree(mod
->init_layout
.base
);
3126 module_memfree(mod
->core_layout
.base
);
3129 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3130 const Elf_Shdr
*sechdrs
,
3136 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3138 /* Sort exception table now relocations are done. */
3139 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3141 /* Copy relocated percpu area over. */
3142 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3143 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3145 /* Setup kallsyms-specific fields. */
3146 add_kallsyms(mod
, info
);
3148 /* Arch-specific module finalizing. */
3149 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3152 /* Is this module of this name done loading? No locks held. */
3153 static bool finished_loading(const char *name
)
3159 * The module_mutex should not be a heavily contended lock;
3160 * if we get the occasional sleep here, we'll go an extra iteration
3161 * in the wait_event_interruptible(), which is harmless.
3163 sched_annotate_sleep();
3164 mutex_lock(&module_mutex
);
3165 mod
= find_module_all(name
, strlen(name
), true);
3166 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
3167 || mod
->state
== MODULE_STATE_GOING
;
3168 mutex_unlock(&module_mutex
);
3173 /* Call module constructors. */
3174 static void do_mod_ctors(struct module
*mod
)
3176 #ifdef CONFIG_CONSTRUCTORS
3179 for (i
= 0; i
< mod
->num_ctors
; i
++)
3184 /* For freeing module_init on success, in case kallsyms traversing */
3185 struct mod_initfree
{
3186 struct rcu_head rcu
;
3190 static void do_free_init(struct rcu_head
*head
)
3192 struct mod_initfree
*m
= container_of(head
, struct mod_initfree
, rcu
);
3193 module_memfree(m
->module_init
);
3198 * This is where the real work happens.
3200 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3201 * helper command 'lx-symbols'.
3203 static noinline
int do_init_module(struct module
*mod
)
3206 struct mod_initfree
*freeinit
;
3208 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3213 freeinit
->module_init
= mod
->init_layout
.base
;
3216 * We want to find out whether @mod uses async during init. Clear
3217 * PF_USED_ASYNC. async_schedule*() will set it.
3219 current
->flags
&= ~PF_USED_ASYNC
;
3222 /* Start the module */
3223 if (mod
->init
!= NULL
)
3224 ret
= do_one_initcall(mod
->init
);
3226 goto fail_free_freeinit
;
3229 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3230 "follow 0/-E convention\n"
3231 "%s: loading module anyway...\n",
3232 __func__
, mod
->name
, ret
, __func__
);
3236 /* Now it's a first class citizen! */
3237 mod
->state
= MODULE_STATE_LIVE
;
3238 blocking_notifier_call_chain(&module_notify_list
,
3239 MODULE_STATE_LIVE
, mod
);
3242 * We need to finish all async code before the module init sequence
3243 * is done. This has potential to deadlock. For example, a newly
3244 * detected block device can trigger request_module() of the
3245 * default iosched from async probing task. Once userland helper
3246 * reaches here, async_synchronize_full() will wait on the async
3247 * task waiting on request_module() and deadlock.
3249 * This deadlock is avoided by perfomring async_synchronize_full()
3250 * iff module init queued any async jobs. This isn't a full
3251 * solution as it will deadlock the same if module loading from
3252 * async jobs nests more than once; however, due to the various
3253 * constraints, this hack seems to be the best option for now.
3254 * Please refer to the following thread for details.
3256 * http://thread.gmane.org/gmane.linux.kernel/1420814
3258 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3259 async_synchronize_full();
3261 mutex_lock(&module_mutex
);
3262 /* Drop initial reference. */
3264 trim_init_extable(mod
);
3265 #ifdef CONFIG_KALLSYMS
3266 mod
->num_symtab
= mod
->core_num_syms
;
3267 mod
->symtab
= mod
->core_symtab
;
3268 mod
->strtab
= mod
->core_strtab
;
3270 mod_tree_remove_init(mod
);
3271 disable_ro_nx(&mod
->init_layout
);
3272 module_arch_freeing_init(mod
);
3273 mod
->init_layout
.base
= NULL
;
3274 mod
->init_layout
.size
= 0;
3275 mod
->init_layout
.ro_size
= 0;
3276 mod
->init_layout
.text_size
= 0;
3278 * We want to free module_init, but be aware that kallsyms may be
3279 * walking this with preempt disabled. In all the failure paths, we
3280 * call synchronize_sched(), but we don't want to slow down the success
3281 * path, so use actual RCU here.
3283 call_rcu_sched(&freeinit
->rcu
, do_free_init
);
3284 mutex_unlock(&module_mutex
);
3285 wake_up_all(&module_wq
);
3292 /* Try to protect us from buggy refcounters. */
3293 mod
->state
= MODULE_STATE_GOING
;
3294 synchronize_sched();
3296 blocking_notifier_call_chain(&module_notify_list
,
3297 MODULE_STATE_GOING
, mod
);
3299 wake_up_all(&module_wq
);
3303 static int may_init_module(void)
3305 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3312 * We try to place it in the list now to make sure it's unique before
3313 * we dedicate too many resources. In particular, temporary percpu
3314 * memory exhaustion.
3316 static int add_unformed_module(struct module
*mod
)
3321 mod
->state
= MODULE_STATE_UNFORMED
;
3324 mutex_lock(&module_mutex
);
3325 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3327 if (old
->state
== MODULE_STATE_COMING
3328 || old
->state
== MODULE_STATE_UNFORMED
) {
3329 /* Wait in case it fails to load. */
3330 mutex_unlock(&module_mutex
);
3331 err
= wait_event_interruptible(module_wq
,
3332 finished_loading(mod
->name
));
3340 mod_update_bounds(mod
);
3341 list_add_rcu(&mod
->list
, &modules
);
3342 mod_tree_insert(mod
);
3346 mutex_unlock(&module_mutex
);
3351 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3355 mutex_lock(&module_mutex
);
3357 /* Find duplicate symbols (must be called under lock). */
3358 err
= verify_export_symbols(mod
);
3362 /* This relies on module_mutex for list integrity. */
3363 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3365 /* Set RO and NX regions */
3366 module_enable_ro(mod
);
3367 module_enable_nx(mod
);
3369 /* Mark state as coming so strong_try_module_get() ignores us,
3370 * but kallsyms etc. can see us. */
3371 mod
->state
= MODULE_STATE_COMING
;
3372 mutex_unlock(&module_mutex
);
3374 blocking_notifier_call_chain(&module_notify_list
,
3375 MODULE_STATE_COMING
, mod
);
3379 mutex_unlock(&module_mutex
);
3383 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3386 struct module
*mod
= arg
;
3389 if (strcmp(param
, "async_probe") == 0) {
3390 mod
->async_probe_requested
= true;
3394 /* Check for magic 'dyndbg' arg */
3395 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3397 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3401 /* Allocate and load the module: note that size of section 0 is always
3402 zero, and we rely on this for optional sections. */
3403 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3410 err
= module_sig_check(info
);
3414 err
= elf_header_check(info
);
3418 /* Figure out module layout, and allocate all the memory. */
3419 mod
= layout_and_allocate(info
, flags
);
3425 /* Reserve our place in the list. */
3426 err
= add_unformed_module(mod
);
3430 #ifdef CONFIG_MODULE_SIG
3431 mod
->sig_ok
= info
->sig_ok
;
3433 pr_notice_once("%s: module verification failed: signature "
3434 "and/or required key missing - tainting "
3435 "kernel\n", mod
->name
);
3436 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3440 /* To avoid stressing percpu allocator, do this once we're unique. */
3441 err
= percpu_modalloc(mod
, info
);
3445 /* Now module is in final location, initialize linked lists, etc. */
3446 err
= module_unload_init(mod
);
3450 init_param_lock(mod
);
3452 /* Now we've got everything in the final locations, we can
3453 * find optional sections. */
3454 err
= find_module_sections(mod
, info
);
3458 err
= check_module_license_and_versions(mod
);
3462 /* Set up MODINFO_ATTR fields */
3463 setup_modinfo(mod
, info
);
3465 /* Fix up syms, so that st_value is a pointer to location. */
3466 err
= simplify_symbols(mod
, info
);
3470 err
= apply_relocations(mod
, info
);
3474 err
= post_relocation(mod
, info
);
3478 flush_module_icache(mod
);
3480 /* Now copy in args */
3481 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3482 if (IS_ERR(mod
->args
)) {
3483 err
= PTR_ERR(mod
->args
);
3484 goto free_arch_cleanup
;
3487 dynamic_debug_setup(info
->debug
, info
->num_debug
);
3489 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3490 ftrace_module_init(mod
);
3492 /* Finally it's fully formed, ready to start executing. */
3493 err
= complete_formation(mod
, info
);
3495 goto ddebug_cleanup
;
3497 /* Module is ready to execute: parsing args may do that. */
3498 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3499 -32768, 32767, NULL
,
3500 unknown_module_param_cb
);
3501 if (IS_ERR(after_dashes
)) {
3502 err
= PTR_ERR(after_dashes
);
3504 } else if (after_dashes
) {
3505 pr_warn("%s: parameters '%s' after `--' ignored\n",
3506 mod
->name
, after_dashes
);
3509 /* Link in to syfs. */
3510 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3514 /* Get rid of temporary copy. */
3518 trace_module_load(mod
);
3520 return do_init_module(mod
);
3523 /* module_bug_cleanup needs module_mutex protection */
3524 mutex_lock(&module_mutex
);
3525 module_bug_cleanup(mod
);
3526 mutex_unlock(&module_mutex
);
3528 blocking_notifier_call_chain(&module_notify_list
,
3529 MODULE_STATE_GOING
, mod
);
3531 /* we can't deallocate the module until we clear memory protection */
3532 module_disable_ro(mod
);
3533 module_disable_nx(mod
);
3536 dynamic_debug_remove(info
->debug
);
3537 synchronize_sched();
3540 module_arch_cleanup(mod
);
3544 module_unload_free(mod
);
3546 mutex_lock(&module_mutex
);
3547 /* Unlink carefully: kallsyms could be walking list. */
3548 list_del_rcu(&mod
->list
);
3549 mod_tree_remove(mod
);
3550 wake_up_all(&module_wq
);
3551 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3552 synchronize_sched();
3553 mutex_unlock(&module_mutex
);
3556 * Ftrace needs to clean up what it initialized.
3557 * This does nothing if ftrace_module_init() wasn't called,
3558 * but it must be called outside of module_mutex.
3560 ftrace_release_mod(mod
);
3561 /* Free lock-classes; relies on the preceding sync_rcu() */
3562 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
3564 module_deallocate(mod
, info
);
3570 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
3571 unsigned long, len
, const char __user
*, uargs
)
3574 struct load_info info
= { };
3576 err
= may_init_module();
3580 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3583 err
= copy_module_from_user(umod
, len
, &info
);
3587 return load_module(&info
, uargs
, 0);
3590 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
3593 struct load_info info
= { };
3595 err
= may_init_module();
3599 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
3601 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
3602 |MODULE_INIT_IGNORE_VERMAGIC
))
3605 err
= copy_module_from_fd(fd
, &info
);
3609 return load_module(&info
, uargs
, flags
);
3612 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
3614 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
3617 #ifdef CONFIG_KALLSYMS
3619 * This ignores the intensely annoying "mapping symbols" found
3620 * in ARM ELF files: $a, $t and $d.
3622 static inline int is_arm_mapping_symbol(const char *str
)
3624 if (str
[0] == '.' && str
[1] == 'L')
3626 return str
[0] == '$' && strchr("axtd", str
[1])
3627 && (str
[2] == '\0' || str
[2] == '.');
3630 static const char *get_ksymbol(struct module
*mod
,
3632 unsigned long *size
,
3633 unsigned long *offset
)
3635 unsigned int i
, best
= 0;
3636 unsigned long nextval
;
3638 /* At worse, next value is at end of module */
3639 if (within_module_init(addr
, mod
))
3640 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
3642 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
3644 /* Scan for closest preceding symbol, and next symbol. (ELF
3645 starts real symbols at 1). */
3646 for (i
= 1; i
< mod
->num_symtab
; i
++) {
3647 if (mod
->symtab
[i
].st_shndx
== SHN_UNDEF
)
3650 /* We ignore unnamed symbols: they're uninformative
3651 * and inserted at a whim. */
3652 if (mod
->symtab
[i
].st_value
<= addr
3653 && mod
->symtab
[i
].st_value
> mod
->symtab
[best
].st_value
3654 && *(mod
->strtab
+ mod
->symtab
[i
].st_name
) != '\0'
3655 && !is_arm_mapping_symbol(mod
->strtab
+ mod
->symtab
[i
].st_name
))
3657 if (mod
->symtab
[i
].st_value
> addr
3658 && mod
->symtab
[i
].st_value
< nextval
3659 && *(mod
->strtab
+ mod
->symtab
[i
].st_name
) != '\0'
3660 && !is_arm_mapping_symbol(mod
->strtab
+ mod
->symtab
[i
].st_name
))
3661 nextval
= mod
->symtab
[i
].st_value
;
3668 *size
= nextval
- mod
->symtab
[best
].st_value
;
3670 *offset
= addr
- mod
->symtab
[best
].st_value
;
3671 return mod
->strtab
+ mod
->symtab
[best
].st_name
;
3674 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3675 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3676 const char *module_address_lookup(unsigned long addr
,
3677 unsigned long *size
,
3678 unsigned long *offset
,
3682 const char *ret
= NULL
;
3686 mod
= __module_address(addr
);
3689 *modname
= mod
->name
;
3690 ret
= get_ksymbol(mod
, addr
, size
, offset
);
3692 /* Make a copy in here where it's safe */
3694 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
3702 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
3707 list_for_each_entry_rcu(mod
, &modules
, list
) {
3708 if (mod
->state
== MODULE_STATE_UNFORMED
)
3710 if (within_module(addr
, mod
)) {
3713 sym
= get_ksymbol(mod
, addr
, NULL
, NULL
);
3716 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
3726 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
3727 unsigned long *offset
, char *modname
, char *name
)
3732 list_for_each_entry_rcu(mod
, &modules
, list
) {
3733 if (mod
->state
== MODULE_STATE_UNFORMED
)
3735 if (within_module(addr
, mod
)) {
3738 sym
= get_ksymbol(mod
, addr
, size
, offset
);
3742 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
3744 strlcpy(name
, sym
, KSYM_NAME_LEN
);
3754 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
3755 char *name
, char *module_name
, int *exported
)
3760 list_for_each_entry_rcu(mod
, &modules
, list
) {
3761 if (mod
->state
== MODULE_STATE_UNFORMED
)
3763 if (symnum
< mod
->num_symtab
) {
3764 *value
= mod
->symtab
[symnum
].st_value
;
3765 *type
= mod
->symtab
[symnum
].st_info
;
3766 strlcpy(name
, mod
->strtab
+ mod
->symtab
[symnum
].st_name
,
3768 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
3769 *exported
= is_exported(name
, *value
, mod
);
3773 symnum
-= mod
->num_symtab
;
3779 static unsigned long mod_find_symname(struct module
*mod
, const char *name
)
3783 for (i
= 0; i
< mod
->num_symtab
; i
++)
3784 if (strcmp(name
, mod
->strtab
+mod
->symtab
[i
].st_name
) == 0 &&
3785 mod
->symtab
[i
].st_info
!= 'U')
3786 return mod
->symtab
[i
].st_value
;
3790 /* Look for this name: can be of form module:name. */
3791 unsigned long module_kallsyms_lookup_name(const char *name
)
3795 unsigned long ret
= 0;
3797 /* Don't lock: we're in enough trouble already. */
3799 if ((colon
= strchr(name
, ':')) != NULL
) {
3800 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
3801 ret
= mod_find_symname(mod
, colon
+1);
3803 list_for_each_entry_rcu(mod
, &modules
, list
) {
3804 if (mod
->state
== MODULE_STATE_UNFORMED
)
3806 if ((ret
= mod_find_symname(mod
, name
)) != 0)
3814 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
3815 struct module
*, unsigned long),
3822 module_assert_mutex();
3824 list_for_each_entry(mod
, &modules
, list
) {
3825 if (mod
->state
== MODULE_STATE_UNFORMED
)
3827 for (i
= 0; i
< mod
->num_symtab
; i
++) {
3828 ret
= fn(data
, mod
->strtab
+ mod
->symtab
[i
].st_name
,
3829 mod
, mod
->symtab
[i
].st_value
);
3836 #endif /* CONFIG_KALLSYMS */
3838 static char *module_flags(struct module
*mod
, char *buf
)
3842 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
3844 mod
->state
== MODULE_STATE_GOING
||
3845 mod
->state
== MODULE_STATE_COMING
) {
3847 bx
+= module_flags_taint(mod
, buf
+ bx
);
3848 /* Show a - for module-is-being-unloaded */
3849 if (mod
->state
== MODULE_STATE_GOING
)
3851 /* Show a + for module-is-being-loaded */
3852 if (mod
->state
== MODULE_STATE_COMING
)
3861 #ifdef CONFIG_PROC_FS
3862 /* Called by the /proc file system to return a list of modules. */
3863 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
3865 mutex_lock(&module_mutex
);
3866 return seq_list_start(&modules
, *pos
);
3869 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
3871 return seq_list_next(p
, &modules
, pos
);
3874 static void m_stop(struct seq_file
*m
, void *p
)
3876 mutex_unlock(&module_mutex
);
3879 static int m_show(struct seq_file
*m
, void *p
)
3881 struct module
*mod
= list_entry(p
, struct module
, list
);
3884 /* We always ignore unformed modules. */
3885 if (mod
->state
== MODULE_STATE_UNFORMED
)
3888 seq_printf(m
, "%s %u",
3889 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
3890 print_unload_info(m
, mod
);
3892 /* Informative for users. */
3893 seq_printf(m
, " %s",
3894 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
3895 mod
->state
== MODULE_STATE_COMING
? "Loading" :
3897 /* Used by oprofile and other similar tools. */
3898 seq_printf(m
, " 0x%pK", mod
->core_layout
.base
);
3902 seq_printf(m
, " %s", module_flags(mod
, buf
));
3908 /* Format: modulename size refcount deps address
3910 Where refcount is a number or -, and deps is a comma-separated list
3913 static const struct seq_operations modules_op
= {
3920 static int modules_open(struct inode
*inode
, struct file
*file
)
3922 return seq_open(file
, &modules_op
);
3925 static const struct file_operations proc_modules_operations
= {
3926 .open
= modules_open
,
3928 .llseek
= seq_lseek
,
3929 .release
= seq_release
,
3932 static int __init
proc_modules_init(void)
3934 proc_create("modules", 0, NULL
, &proc_modules_operations
);
3937 module_init(proc_modules_init
);
3940 /* Given an address, look for it in the module exception tables. */
3941 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
3943 const struct exception_table_entry
*e
= NULL
;
3947 list_for_each_entry_rcu(mod
, &modules
, list
) {
3948 if (mod
->state
== MODULE_STATE_UNFORMED
)
3950 if (mod
->num_exentries
== 0)
3953 e
= search_extable(mod
->extable
,
3954 mod
->extable
+ mod
->num_exentries
- 1,
3961 /* Now, if we found one, we are running inside it now, hence
3962 we cannot unload the module, hence no refcnt needed. */
3967 * is_module_address - is this address inside a module?
3968 * @addr: the address to check.
3970 * See is_module_text_address() if you simply want to see if the address
3971 * is code (not data).
3973 bool is_module_address(unsigned long addr
)
3978 ret
= __module_address(addr
) != NULL
;
3985 * __module_address - get the module which contains an address.
3986 * @addr: the address.
3988 * Must be called with preempt disabled or module mutex held so that
3989 * module doesn't get freed during this.
3991 struct module
*__module_address(unsigned long addr
)
3995 if (addr
< module_addr_min
|| addr
> module_addr_max
)
3998 module_assert_mutex_or_preempt();
4000 mod
= mod_find(addr
);
4002 BUG_ON(!within_module(addr
, mod
));
4003 if (mod
->state
== MODULE_STATE_UNFORMED
)
4008 EXPORT_SYMBOL_GPL(__module_address
);
4011 * is_module_text_address - is this address inside module code?
4012 * @addr: the address to check.
4014 * See is_module_address() if you simply want to see if the address is
4015 * anywhere in a module. See kernel_text_address() for testing if an
4016 * address corresponds to kernel or module code.
4018 bool is_module_text_address(unsigned long addr
)
4023 ret
= __module_text_address(addr
) != NULL
;
4030 * __module_text_address - get the module whose code contains an address.
4031 * @addr: the address.
4033 * Must be called with preempt disabled or module mutex held so that
4034 * module doesn't get freed during this.
4036 struct module
*__module_text_address(unsigned long addr
)
4038 struct module
*mod
= __module_address(addr
);
4040 /* Make sure it's within the text section. */
4041 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4042 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4047 EXPORT_SYMBOL_GPL(__module_text_address
);
4049 /* Don't grab lock, we're oopsing. */
4050 void print_modules(void)
4055 printk(KERN_DEFAULT
"Modules linked in:");
4056 /* Most callers should already have preempt disabled, but make sure */
4058 list_for_each_entry_rcu(mod
, &modules
, list
) {
4059 if (mod
->state
== MODULE_STATE_UNFORMED
)
4061 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4064 if (last_unloaded_module
[0])
4065 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4069 #ifdef CONFIG_MODVERSIONS
4070 /* Generate the signature for all relevant module structures here.
4071 * If these change, we don't want to try to parse the module. */
4072 void module_layout(struct module
*mod
,
4073 struct modversion_info
*ver
,
4074 struct kernel_param
*kp
,
4075 struct kernel_symbol
*ks
,
4076 struct tracepoint
* const *tp
)
4079 EXPORT_SYMBOL(module_layout
);