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/extable.h>
21 #include <linux/moduleloader.h>
22 #include <linux/trace_events.h>
23 #include <linux/init.h>
24 #include <linux/kallsyms.h>
25 #include <linux/file.h>
27 #include <linux/sysfs.h>
28 #include <linux/kernel.h>
29 #include <linux/slab.h>
30 #include <linux/vmalloc.h>
31 #include <linux/elf.h>
32 #include <linux/proc_fs.h>
33 #include <linux/security.h>
34 #include <linux/seq_file.h>
35 #include <linux/syscalls.h>
36 #include <linux/fcntl.h>
37 #include <linux/rcupdate.h>
38 #include <linux/capability.h>
39 #include <linux/cpu.h>
40 #include <linux/moduleparam.h>
41 #include <linux/errno.h>
42 #include <linux/err.h>
43 #include <linux/vermagic.h>
44 #include <linux/notifier.h>
45 #include <linux/sched.h>
46 #include <linux/device.h>
47 #include <linux/string.h>
48 #include <linux/mutex.h>
49 #include <linux/rculist.h>
50 #include <linux/uaccess.h>
51 #include <asm/cacheflush.h>
52 #include <linux/set_memory.h>
53 #include <asm/mmu_context.h>
54 #include <linux/license.h>
55 #include <asm/sections.h>
56 #include <linux/tracepoint.h>
57 #include <linux/ftrace.h>
58 #include <linux/livepatch.h>
59 #include <linux/async.h>
60 #include <linux/percpu.h>
61 #include <linux/kmemleak.h>
62 #include <linux/jump_label.h>
63 #include <linux/pfn.h>
64 #include <linux/bsearch.h>
65 #include <linux/dynamic_debug.h>
66 #include <linux/audit.h>
67 #include <uapi/linux/module.h>
68 #include "module-internal.h"
70 #define CREATE_TRACE_POINTS
71 #include <trace/events/module.h>
73 #ifndef ARCH_SHF_SMALL
74 #define ARCH_SHF_SMALL 0
78 * Modules' sections will be aligned on page boundaries
79 * to ensure complete separation of code and data, but
80 * only when CONFIG_STRICT_MODULE_RWX=y
82 #ifdef CONFIG_STRICT_MODULE_RWX
83 # define debug_align(X) ALIGN(X, PAGE_SIZE)
85 # define debug_align(X) (X)
88 /* If this is set, the section belongs in the init part of the module */
89 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
93 * 1) List of modules (also safely readable with preempt_disable),
94 * 2) module_use links,
95 * 3) module_addr_min/module_addr_max.
96 * (delete and add uses RCU list operations). */
97 DEFINE_MUTEX(module_mutex
);
98 EXPORT_SYMBOL_GPL(module_mutex
);
99 static LIST_HEAD(modules
);
101 /* Work queue for freeing init sections in success case */
102 static struct work_struct init_free_wq
;
103 static struct llist_head init_free_list
;
105 #ifdef CONFIG_MODULES_TREE_LOOKUP
108 * Use a latched RB-tree for __module_address(); this allows us to use
109 * RCU-sched lookups of the address from any context.
111 * This is conditional on PERF_EVENTS || TRACING because those can really hit
112 * __module_address() hard by doing a lot of stack unwinding; potentially from
116 static __always_inline
unsigned long __mod_tree_val(struct latch_tree_node
*n
)
118 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
120 return (unsigned long)layout
->base
;
123 static __always_inline
unsigned long __mod_tree_size(struct latch_tree_node
*n
)
125 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
127 return (unsigned long)layout
->size
;
130 static __always_inline
bool
131 mod_tree_less(struct latch_tree_node
*a
, struct latch_tree_node
*b
)
133 return __mod_tree_val(a
) < __mod_tree_val(b
);
136 static __always_inline
int
137 mod_tree_comp(void *key
, struct latch_tree_node
*n
)
139 unsigned long val
= (unsigned long)key
;
140 unsigned long start
, end
;
142 start
= __mod_tree_val(n
);
146 end
= start
+ __mod_tree_size(n
);
153 static const struct latch_tree_ops mod_tree_ops
= {
154 .less
= mod_tree_less
,
155 .comp
= mod_tree_comp
,
158 static struct mod_tree_root
{
159 struct latch_tree_root root
;
160 unsigned long addr_min
;
161 unsigned long addr_max
;
162 } mod_tree __cacheline_aligned
= {
166 #define module_addr_min mod_tree.addr_min
167 #define module_addr_max mod_tree.addr_max
169 static noinline
void __mod_tree_insert(struct mod_tree_node
*node
)
171 latch_tree_insert(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
174 static void __mod_tree_remove(struct mod_tree_node
*node
)
176 latch_tree_erase(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
180 * These modifications: insert, remove_init and remove; are serialized by the
183 static void mod_tree_insert(struct module
*mod
)
185 mod
->core_layout
.mtn
.mod
= mod
;
186 mod
->init_layout
.mtn
.mod
= mod
;
188 __mod_tree_insert(&mod
->core_layout
.mtn
);
189 if (mod
->init_layout
.size
)
190 __mod_tree_insert(&mod
->init_layout
.mtn
);
193 static void mod_tree_remove_init(struct module
*mod
)
195 if (mod
->init_layout
.size
)
196 __mod_tree_remove(&mod
->init_layout
.mtn
);
199 static void mod_tree_remove(struct module
*mod
)
201 __mod_tree_remove(&mod
->core_layout
.mtn
);
202 mod_tree_remove_init(mod
);
205 static struct module
*mod_find(unsigned long addr
)
207 struct latch_tree_node
*ltn
;
209 ltn
= latch_tree_find((void *)addr
, &mod_tree
.root
, &mod_tree_ops
);
213 return container_of(ltn
, struct mod_tree_node
, node
)->mod
;
216 #else /* MODULES_TREE_LOOKUP */
218 static unsigned long module_addr_min
= -1UL, module_addr_max
= 0;
220 static void mod_tree_insert(struct module
*mod
) { }
221 static void mod_tree_remove_init(struct module
*mod
) { }
222 static void mod_tree_remove(struct module
*mod
) { }
224 static struct module
*mod_find(unsigned long addr
)
228 list_for_each_entry_rcu(mod
, &modules
, list
) {
229 if (within_module(addr
, mod
))
236 #endif /* MODULES_TREE_LOOKUP */
239 * Bounds of module text, for speeding up __module_address.
240 * Protected by module_mutex.
242 static void __mod_update_bounds(void *base
, unsigned int size
)
244 unsigned long min
= (unsigned long)base
;
245 unsigned long max
= min
+ size
;
247 if (min
< module_addr_min
)
248 module_addr_min
= min
;
249 if (max
> module_addr_max
)
250 module_addr_max
= max
;
253 static void mod_update_bounds(struct module
*mod
)
255 __mod_update_bounds(mod
->core_layout
.base
, mod
->core_layout
.size
);
256 if (mod
->init_layout
.size
)
257 __mod_update_bounds(mod
->init_layout
.base
, mod
->init_layout
.size
);
260 #ifdef CONFIG_KGDB_KDB
261 struct list_head
*kdb_modules
= &modules
; /* kdb needs the list of modules */
262 #endif /* CONFIG_KGDB_KDB */
264 static void module_assert_mutex(void)
266 lockdep_assert_held(&module_mutex
);
269 static void module_assert_mutex_or_preempt(void)
271 #ifdef CONFIG_LOCKDEP
272 if (unlikely(!debug_locks
))
275 WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
276 !lockdep_is_held(&module_mutex
));
280 static bool sig_enforce
= IS_ENABLED(CONFIG_MODULE_SIG_FORCE
);
281 module_param(sig_enforce
, bool_enable_only
, 0644);
284 * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
285 * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
287 bool is_module_sig_enforced(void)
291 EXPORT_SYMBOL(is_module_sig_enforced
);
293 void set_module_sig_enforced(void)
298 /* Block module loading/unloading? */
299 int modules_disabled
= 0;
300 core_param(nomodule
, modules_disabled
, bint
, 0);
302 /* Waiting for a module to finish initializing? */
303 static DECLARE_WAIT_QUEUE_HEAD(module_wq
);
305 static BLOCKING_NOTIFIER_HEAD(module_notify_list
);
307 int register_module_notifier(struct notifier_block
*nb
)
309 return blocking_notifier_chain_register(&module_notify_list
, nb
);
311 EXPORT_SYMBOL(register_module_notifier
);
313 int unregister_module_notifier(struct notifier_block
*nb
)
315 return blocking_notifier_chain_unregister(&module_notify_list
, nb
);
317 EXPORT_SYMBOL(unregister_module_notifier
);
320 * We require a truly strong try_module_get(): 0 means success.
321 * Otherwise an error is returned due to ongoing or failed
322 * initialization etc.
324 static inline int strong_try_module_get(struct module
*mod
)
326 BUG_ON(mod
&& mod
->state
== MODULE_STATE_UNFORMED
);
327 if (mod
&& mod
->state
== MODULE_STATE_COMING
)
329 if (try_module_get(mod
))
335 static inline void add_taint_module(struct module
*mod
, unsigned flag
,
336 enum lockdep_ok lockdep_ok
)
338 add_taint(flag
, lockdep_ok
);
339 set_bit(flag
, &mod
->taints
);
343 * A thread that wants to hold a reference to a module only while it
344 * is running can call this to safely exit. nfsd and lockd use this.
346 void __noreturn
__module_put_and_exit(struct module
*mod
, long code
)
351 EXPORT_SYMBOL(__module_put_and_exit
);
353 /* Find a module section: 0 means not found. */
354 static unsigned int find_sec(const struct load_info
*info
, const char *name
)
358 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
359 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
360 /* Alloc bit cleared means "ignore it." */
361 if ((shdr
->sh_flags
& SHF_ALLOC
)
362 && strcmp(info
->secstrings
+ shdr
->sh_name
, name
) == 0)
368 /* Find a module section, or NULL. */
369 static void *section_addr(const struct load_info
*info
, const char *name
)
371 /* Section 0 has sh_addr 0. */
372 return (void *)info
->sechdrs
[find_sec(info
, name
)].sh_addr
;
375 /* Find a module section, or NULL. Fill in number of "objects" in section. */
376 static void *section_objs(const struct load_info
*info
,
381 unsigned int sec
= find_sec(info
, name
);
383 /* Section 0 has sh_addr 0 and sh_size 0. */
384 *num
= info
->sechdrs
[sec
].sh_size
/ object_size
;
385 return (void *)info
->sechdrs
[sec
].sh_addr
;
388 /* Provided by the linker */
389 extern const struct kernel_symbol __start___ksymtab
[];
390 extern const struct kernel_symbol __stop___ksymtab
[];
391 extern const struct kernel_symbol __start___ksymtab_gpl
[];
392 extern const struct kernel_symbol __stop___ksymtab_gpl
[];
393 extern const struct kernel_symbol __start___ksymtab_gpl_future
[];
394 extern const struct kernel_symbol __stop___ksymtab_gpl_future
[];
395 extern const s32 __start___kcrctab
[];
396 extern const s32 __start___kcrctab_gpl
[];
397 extern const s32 __start___kcrctab_gpl_future
[];
398 #ifdef CONFIG_UNUSED_SYMBOLS
399 extern const struct kernel_symbol __start___ksymtab_unused
[];
400 extern const struct kernel_symbol __stop___ksymtab_unused
[];
401 extern const struct kernel_symbol __start___ksymtab_unused_gpl
[];
402 extern const struct kernel_symbol __stop___ksymtab_unused_gpl
[];
403 extern const s32 __start___kcrctab_unused
[];
404 extern const s32 __start___kcrctab_unused_gpl
[];
407 #ifndef CONFIG_MODVERSIONS
408 #define symversion(base, idx) NULL
410 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
413 static bool each_symbol_in_section(const struct symsearch
*arr
,
414 unsigned int arrsize
,
415 struct module
*owner
,
416 bool (*fn
)(const struct symsearch
*syms
,
417 struct module
*owner
,
423 for (j
= 0; j
< arrsize
; j
++) {
424 if (fn(&arr
[j
], owner
, data
))
431 /* Returns true as soon as fn returns true, otherwise false. */
432 bool each_symbol_section(bool (*fn
)(const struct symsearch
*arr
,
433 struct module
*owner
,
438 static const struct symsearch arr
[] = {
439 { __start___ksymtab
, __stop___ksymtab
, __start___kcrctab
,
440 NOT_GPL_ONLY
, false },
441 { __start___ksymtab_gpl
, __stop___ksymtab_gpl
,
442 __start___kcrctab_gpl
,
444 { __start___ksymtab_gpl_future
, __stop___ksymtab_gpl_future
,
445 __start___kcrctab_gpl_future
,
446 WILL_BE_GPL_ONLY
, false },
447 #ifdef CONFIG_UNUSED_SYMBOLS
448 { __start___ksymtab_unused
, __stop___ksymtab_unused
,
449 __start___kcrctab_unused
,
450 NOT_GPL_ONLY
, true },
451 { __start___ksymtab_unused_gpl
, __stop___ksymtab_unused_gpl
,
452 __start___kcrctab_unused_gpl
,
457 module_assert_mutex_or_preempt();
459 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), NULL
, fn
, data
))
462 list_for_each_entry_rcu(mod
, &modules
, list
) {
463 struct symsearch arr
[] = {
464 { mod
->syms
, mod
->syms
+ mod
->num_syms
, mod
->crcs
,
465 NOT_GPL_ONLY
, false },
466 { mod
->gpl_syms
, mod
->gpl_syms
+ mod
->num_gpl_syms
,
469 { mod
->gpl_future_syms
,
470 mod
->gpl_future_syms
+ mod
->num_gpl_future_syms
,
471 mod
->gpl_future_crcs
,
472 WILL_BE_GPL_ONLY
, false },
473 #ifdef CONFIG_UNUSED_SYMBOLS
475 mod
->unused_syms
+ mod
->num_unused_syms
,
477 NOT_GPL_ONLY
, true },
478 { mod
->unused_gpl_syms
,
479 mod
->unused_gpl_syms
+ mod
->num_unused_gpl_syms
,
480 mod
->unused_gpl_crcs
,
485 if (mod
->state
== MODULE_STATE_UNFORMED
)
488 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), mod
, fn
, data
))
493 EXPORT_SYMBOL_GPL(each_symbol_section
);
495 struct find_symbol_arg
{
502 struct module
*owner
;
504 const struct kernel_symbol
*sym
;
507 static bool check_exported_symbol(const struct symsearch
*syms
,
508 struct module
*owner
,
509 unsigned int symnum
, void *data
)
511 struct find_symbol_arg
*fsa
= data
;
514 if (syms
->licence
== GPL_ONLY
)
516 if (syms
->licence
== WILL_BE_GPL_ONLY
&& fsa
->warn
) {
517 pr_warn("Symbol %s is being used by a non-GPL module, "
518 "which will not be allowed in the future\n",
523 #ifdef CONFIG_UNUSED_SYMBOLS
524 if (syms
->unused
&& fsa
->warn
) {
525 pr_warn("Symbol %s is marked as UNUSED, however this module is "
526 "using it.\n", fsa
->name
);
527 pr_warn("This symbol will go away in the future.\n");
528 pr_warn("Please evaluate if this is the right api to use and "
529 "if it really is, submit a report to the linux kernel "
530 "mailing list together with submitting your code for "
536 fsa
->crc
= symversion(syms
->crcs
, symnum
);
537 fsa
->sym
= &syms
->start
[symnum
];
541 static unsigned long kernel_symbol_value(const struct kernel_symbol
*sym
)
543 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
544 return (unsigned long)offset_to_ptr(&sym
->value_offset
);
550 static const char *kernel_symbol_name(const struct kernel_symbol
*sym
)
552 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
553 return offset_to_ptr(&sym
->name_offset
);
559 static int cmp_name(const void *va
, const void *vb
)
562 const struct kernel_symbol
*b
;
564 return strcmp(a
, kernel_symbol_name(b
));
567 static bool find_exported_symbol_in_section(const struct symsearch
*syms
,
568 struct module
*owner
,
571 struct find_symbol_arg
*fsa
= data
;
572 struct kernel_symbol
*sym
;
574 sym
= bsearch(fsa
->name
, syms
->start
, syms
->stop
- syms
->start
,
575 sizeof(struct kernel_symbol
), cmp_name
);
577 if (sym
!= NULL
&& check_exported_symbol(syms
, owner
,
578 sym
- syms
->start
, data
))
584 /* Find an exported symbol and return it, along with, (optional) crc and
585 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
586 const struct kernel_symbol
*find_symbol(const char *name
,
587 struct module
**owner
,
592 struct find_symbol_arg fsa
;
598 if (each_symbol_section(find_exported_symbol_in_section
, &fsa
)) {
606 pr_debug("Failed to find symbol %s\n", name
);
609 EXPORT_SYMBOL_GPL(find_symbol
);
612 * Search for module by name: must hold module_mutex (or preempt disabled
613 * for read-only access).
615 static struct module
*find_module_all(const char *name
, size_t len
,
620 module_assert_mutex_or_preempt();
622 list_for_each_entry_rcu(mod
, &modules
, list
) {
623 if (!even_unformed
&& mod
->state
== MODULE_STATE_UNFORMED
)
625 if (strlen(mod
->name
) == len
&& !memcmp(mod
->name
, name
, len
))
631 struct module
*find_module(const char *name
)
633 module_assert_mutex();
634 return find_module_all(name
, strlen(name
), false);
636 EXPORT_SYMBOL_GPL(find_module
);
640 static inline void __percpu
*mod_percpu(struct module
*mod
)
645 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
647 Elf_Shdr
*pcpusec
= &info
->sechdrs
[info
->index
.pcpu
];
648 unsigned long align
= pcpusec
->sh_addralign
;
650 if (!pcpusec
->sh_size
)
653 if (align
> PAGE_SIZE
) {
654 pr_warn("%s: per-cpu alignment %li > %li\n",
655 mod
->name
, align
, PAGE_SIZE
);
659 mod
->percpu
= __alloc_reserved_percpu(pcpusec
->sh_size
, align
);
661 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
662 mod
->name
, (unsigned long)pcpusec
->sh_size
);
665 mod
->percpu_size
= pcpusec
->sh_size
;
669 static void percpu_modfree(struct module
*mod
)
671 free_percpu(mod
->percpu
);
674 static unsigned int find_pcpusec(struct load_info
*info
)
676 return find_sec(info
, ".data..percpu");
679 static void percpu_modcopy(struct module
*mod
,
680 const void *from
, unsigned long size
)
684 for_each_possible_cpu(cpu
)
685 memcpy(per_cpu_ptr(mod
->percpu
, cpu
), from
, size
);
688 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
695 list_for_each_entry_rcu(mod
, &modules
, list
) {
696 if (mod
->state
== MODULE_STATE_UNFORMED
)
698 if (!mod
->percpu_size
)
700 for_each_possible_cpu(cpu
) {
701 void *start
= per_cpu_ptr(mod
->percpu
, cpu
);
702 void *va
= (void *)addr
;
704 if (va
>= start
&& va
< start
+ mod
->percpu_size
) {
706 *can_addr
= (unsigned long) (va
- start
);
707 *can_addr
+= (unsigned long)
708 per_cpu_ptr(mod
->percpu
,
722 * is_module_percpu_address - test whether address is from module static percpu
723 * @addr: address to test
725 * Test whether @addr belongs to module static percpu area.
728 * %true if @addr is from module static percpu area
730 bool is_module_percpu_address(unsigned long addr
)
732 return __is_module_percpu_address(addr
, NULL
);
735 #else /* ... !CONFIG_SMP */
737 static inline void __percpu
*mod_percpu(struct module
*mod
)
741 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
743 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
744 if (info
->sechdrs
[info
->index
.pcpu
].sh_size
!= 0)
748 static inline void percpu_modfree(struct module
*mod
)
751 static unsigned int find_pcpusec(struct load_info
*info
)
755 static inline void percpu_modcopy(struct module
*mod
,
756 const void *from
, unsigned long size
)
758 /* pcpusec should be 0, and size of that section should be 0. */
761 bool is_module_percpu_address(unsigned long addr
)
766 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
771 #endif /* CONFIG_SMP */
773 #define MODINFO_ATTR(field) \
774 static void setup_modinfo_##field(struct module *mod, const char *s) \
776 mod->field = kstrdup(s, GFP_KERNEL); \
778 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
779 struct module_kobject *mk, char *buffer) \
781 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
783 static int modinfo_##field##_exists(struct module *mod) \
785 return mod->field != NULL; \
787 static void free_modinfo_##field(struct module *mod) \
792 static struct module_attribute modinfo_##field = { \
793 .attr = { .name = __stringify(field), .mode = 0444 }, \
794 .show = show_modinfo_##field, \
795 .setup = setup_modinfo_##field, \
796 .test = modinfo_##field##_exists, \
797 .free = free_modinfo_##field, \
800 MODINFO_ATTR(version
);
801 MODINFO_ATTR(srcversion
);
803 static char last_unloaded_module
[MODULE_NAME_LEN
+1];
805 #ifdef CONFIG_MODULE_UNLOAD
807 EXPORT_TRACEPOINT_SYMBOL(module_get
);
809 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
810 #define MODULE_REF_BASE 1
812 /* Init the unload section of the module. */
813 static int module_unload_init(struct module
*mod
)
816 * Initialize reference counter to MODULE_REF_BASE.
817 * refcnt == 0 means module is going.
819 atomic_set(&mod
->refcnt
, MODULE_REF_BASE
);
821 INIT_LIST_HEAD(&mod
->source_list
);
822 INIT_LIST_HEAD(&mod
->target_list
);
824 /* Hold reference count during initialization. */
825 atomic_inc(&mod
->refcnt
);
830 /* Does a already use b? */
831 static int already_uses(struct module
*a
, struct module
*b
)
833 struct module_use
*use
;
835 list_for_each_entry(use
, &b
->source_list
, source_list
) {
836 if (use
->source
== a
) {
837 pr_debug("%s uses %s!\n", a
->name
, b
->name
);
841 pr_debug("%s does not use %s!\n", a
->name
, b
->name
);
847 * - we add 'a' as a "source", 'b' as a "target" of module use
848 * - the module_use is added to the list of 'b' sources (so
849 * 'b' can walk the list to see who sourced them), and of 'a'
850 * targets (so 'a' can see what modules it targets).
852 static int add_module_usage(struct module
*a
, struct module
*b
)
854 struct module_use
*use
;
856 pr_debug("Allocating new usage for %s.\n", a
->name
);
857 use
= kmalloc(sizeof(*use
), GFP_ATOMIC
);
863 list_add(&use
->source_list
, &b
->source_list
);
864 list_add(&use
->target_list
, &a
->target_list
);
868 /* Module a uses b: caller needs module_mutex() */
869 int ref_module(struct module
*a
, struct module
*b
)
873 if (b
== NULL
|| already_uses(a
, b
))
876 /* If module isn't available, we fail. */
877 err
= strong_try_module_get(b
);
881 err
= add_module_usage(a
, b
);
888 EXPORT_SYMBOL_GPL(ref_module
);
890 /* Clear the unload stuff of the module. */
891 static void module_unload_free(struct module
*mod
)
893 struct module_use
*use
, *tmp
;
895 mutex_lock(&module_mutex
);
896 list_for_each_entry_safe(use
, tmp
, &mod
->target_list
, target_list
) {
897 struct module
*i
= use
->target
;
898 pr_debug("%s unusing %s\n", mod
->name
, i
->name
);
900 list_del(&use
->source_list
);
901 list_del(&use
->target_list
);
904 mutex_unlock(&module_mutex
);
907 #ifdef CONFIG_MODULE_FORCE_UNLOAD
908 static inline int try_force_unload(unsigned int flags
)
910 int ret
= (flags
& O_TRUNC
);
912 add_taint(TAINT_FORCED_RMMOD
, LOCKDEP_NOW_UNRELIABLE
);
916 static inline int try_force_unload(unsigned int flags
)
920 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
922 /* Try to release refcount of module, 0 means success. */
923 static int try_release_module_ref(struct module
*mod
)
927 /* Try to decrement refcnt which we set at loading */
928 ret
= atomic_sub_return(MODULE_REF_BASE
, &mod
->refcnt
);
931 /* Someone can put this right now, recover with checking */
932 ret
= atomic_add_unless(&mod
->refcnt
, MODULE_REF_BASE
, 0);
937 static int try_stop_module(struct module
*mod
, int flags
, int *forced
)
939 /* If it's not unused, quit unless we're forcing. */
940 if (try_release_module_ref(mod
) != 0) {
941 *forced
= try_force_unload(flags
);
946 /* Mark it as dying. */
947 mod
->state
= MODULE_STATE_GOING
;
953 * module_refcount - return the refcount or -1 if unloading
955 * @mod: the module we're checking
958 * -1 if the module is in the process of unloading
959 * otherwise the number of references in the kernel to the module
961 int module_refcount(struct module
*mod
)
963 return atomic_read(&mod
->refcnt
) - MODULE_REF_BASE
;
965 EXPORT_SYMBOL(module_refcount
);
967 /* This exists whether we can unload or not */
968 static void free_module(struct module
*mod
);
970 SYSCALL_DEFINE2(delete_module
, const char __user
*, name_user
,
974 char name
[MODULE_NAME_LEN
];
977 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
980 if (strncpy_from_user(name
, name_user
, MODULE_NAME_LEN
-1) < 0)
982 name
[MODULE_NAME_LEN
-1] = '\0';
984 audit_log_kern_module(name
);
986 if (mutex_lock_interruptible(&module_mutex
) != 0)
989 mod
= find_module(name
);
995 if (!list_empty(&mod
->source_list
)) {
996 /* Other modules depend on us: get rid of them first. */
1001 /* Doing init or already dying? */
1002 if (mod
->state
!= MODULE_STATE_LIVE
) {
1003 /* FIXME: if (force), slam module count damn the torpedoes */
1004 pr_debug("%s already dying\n", mod
->name
);
1009 /* If it has an init func, it must have an exit func to unload */
1010 if (mod
->init
&& !mod
->exit
) {
1011 forced
= try_force_unload(flags
);
1013 /* This module can't be removed */
1019 /* Stop the machine so refcounts can't move and disable module. */
1020 ret
= try_stop_module(mod
, flags
, &forced
);
1024 mutex_unlock(&module_mutex
);
1025 /* Final destruction now no one is using it. */
1026 if (mod
->exit
!= NULL
)
1028 blocking_notifier_call_chain(&module_notify_list
,
1029 MODULE_STATE_GOING
, mod
);
1030 klp_module_going(mod
);
1031 ftrace_release_mod(mod
);
1033 async_synchronize_full();
1035 /* Store the name of the last unloaded module for diagnostic purposes */
1036 strlcpy(last_unloaded_module
, mod
->name
, sizeof(last_unloaded_module
));
1041 mutex_unlock(&module_mutex
);
1045 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1047 struct module_use
*use
;
1048 int printed_something
= 0;
1050 seq_printf(m
, " %i ", module_refcount(mod
));
1053 * Always include a trailing , so userspace can differentiate
1054 * between this and the old multi-field proc format.
1056 list_for_each_entry(use
, &mod
->source_list
, source_list
) {
1057 printed_something
= 1;
1058 seq_printf(m
, "%s,", use
->source
->name
);
1061 if (mod
->init
!= NULL
&& mod
->exit
== NULL
) {
1062 printed_something
= 1;
1063 seq_puts(m
, "[permanent],");
1066 if (!printed_something
)
1070 void __symbol_put(const char *symbol
)
1072 struct module
*owner
;
1075 if (!find_symbol(symbol
, &owner
, NULL
, true, false))
1080 EXPORT_SYMBOL(__symbol_put
);
1082 /* Note this assumes addr is a function, which it currently always is. */
1083 void symbol_put_addr(void *addr
)
1085 struct module
*modaddr
;
1086 unsigned long a
= (unsigned long)dereference_function_descriptor(addr
);
1088 if (core_kernel_text(a
))
1092 * Even though we hold a reference on the module; we still need to
1093 * disable preemption in order to safely traverse the data structure.
1096 modaddr
= __module_text_address(a
);
1098 module_put(modaddr
);
1101 EXPORT_SYMBOL_GPL(symbol_put_addr
);
1103 static ssize_t
show_refcnt(struct module_attribute
*mattr
,
1104 struct module_kobject
*mk
, char *buffer
)
1106 return sprintf(buffer
, "%i\n", module_refcount(mk
->mod
));
1109 static struct module_attribute modinfo_refcnt
=
1110 __ATTR(refcnt
, 0444, show_refcnt
, NULL
);
1112 void __module_get(struct module
*module
)
1116 atomic_inc(&module
->refcnt
);
1117 trace_module_get(module
, _RET_IP_
);
1121 EXPORT_SYMBOL(__module_get
);
1123 bool try_module_get(struct module
*module
)
1129 /* Note: here, we can fail to get a reference */
1130 if (likely(module_is_live(module
) &&
1131 atomic_inc_not_zero(&module
->refcnt
) != 0))
1132 trace_module_get(module
, _RET_IP_
);
1140 EXPORT_SYMBOL(try_module_get
);
1142 void module_put(struct module
*module
)
1148 ret
= atomic_dec_if_positive(&module
->refcnt
);
1149 WARN_ON(ret
< 0); /* Failed to put refcount */
1150 trace_module_put(module
, _RET_IP_
);
1154 EXPORT_SYMBOL(module_put
);
1156 #else /* !CONFIG_MODULE_UNLOAD */
1157 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1159 /* We don't know the usage count, or what modules are using. */
1160 seq_puts(m
, " - -");
1163 static inline void module_unload_free(struct module
*mod
)
1167 int ref_module(struct module
*a
, struct module
*b
)
1169 return strong_try_module_get(b
);
1171 EXPORT_SYMBOL_GPL(ref_module
);
1173 static inline int module_unload_init(struct module
*mod
)
1177 #endif /* CONFIG_MODULE_UNLOAD */
1179 static size_t module_flags_taint(struct module
*mod
, char *buf
)
1184 for (i
= 0; i
< TAINT_FLAGS_COUNT
; i
++) {
1185 if (taint_flags
[i
].module
&& test_bit(i
, &mod
->taints
))
1186 buf
[l
++] = taint_flags
[i
].c_true
;
1192 static ssize_t
show_initstate(struct module_attribute
*mattr
,
1193 struct module_kobject
*mk
, char *buffer
)
1195 const char *state
= "unknown";
1197 switch (mk
->mod
->state
) {
1198 case MODULE_STATE_LIVE
:
1201 case MODULE_STATE_COMING
:
1204 case MODULE_STATE_GOING
:
1210 return sprintf(buffer
, "%s\n", state
);
1213 static struct module_attribute modinfo_initstate
=
1214 __ATTR(initstate
, 0444, show_initstate
, NULL
);
1216 static ssize_t
store_uevent(struct module_attribute
*mattr
,
1217 struct module_kobject
*mk
,
1218 const char *buffer
, size_t count
)
1222 rc
= kobject_synth_uevent(&mk
->kobj
, buffer
, count
);
1223 return rc
? rc
: count
;
1226 struct module_attribute module_uevent
=
1227 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1229 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1230 struct module_kobject
*mk
, char *buffer
)
1232 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1235 static struct module_attribute modinfo_coresize
=
1236 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1238 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1239 struct module_kobject
*mk
, char *buffer
)
1241 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1244 static struct module_attribute modinfo_initsize
=
1245 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1247 static ssize_t
show_taint(struct module_attribute
*mattr
,
1248 struct module_kobject
*mk
, char *buffer
)
1252 l
= module_flags_taint(mk
->mod
, buffer
);
1257 static struct module_attribute modinfo_taint
=
1258 __ATTR(taint
, 0444, show_taint
, NULL
);
1260 static struct module_attribute
*modinfo_attrs
[] = {
1263 &modinfo_srcversion
,
1268 #ifdef CONFIG_MODULE_UNLOAD
1274 static const char vermagic
[] = VERMAGIC_STRING
;
1276 static int try_to_force_load(struct module
*mod
, const char *reason
)
1278 #ifdef CONFIG_MODULE_FORCE_LOAD
1279 if (!test_taint(TAINT_FORCED_MODULE
))
1280 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1281 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1288 #ifdef CONFIG_MODVERSIONS
1290 static u32
resolve_rel_crc(const s32
*crc
)
1292 return *(u32
*)((void *)crc
+ *crc
);
1295 static int check_version(const struct load_info
*info
,
1296 const char *symname
,
1300 Elf_Shdr
*sechdrs
= info
->sechdrs
;
1301 unsigned int versindex
= info
->index
.vers
;
1302 unsigned int i
, num_versions
;
1303 struct modversion_info
*versions
;
1305 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1309 /* No versions at all? modprobe --force does this. */
1311 return try_to_force_load(mod
, symname
) == 0;
1313 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1314 num_versions
= sechdrs
[versindex
].sh_size
1315 / sizeof(struct modversion_info
);
1317 for (i
= 0; i
< num_versions
; i
++) {
1320 if (strcmp(versions
[i
].name
, symname
) != 0)
1323 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS
))
1324 crcval
= resolve_rel_crc(crc
);
1327 if (versions
[i
].crc
== crcval
)
1329 pr_debug("Found checksum %X vs module %lX\n",
1330 crcval
, versions
[i
].crc
);
1334 /* Broken toolchain. Warn once, then let it go.. */
1335 pr_warn_once("%s: no symbol version for %s\n", info
->name
, symname
);
1339 pr_warn("%s: disagrees about version of symbol %s\n",
1340 info
->name
, symname
);
1344 static inline int check_modstruct_version(const struct load_info
*info
,
1350 * Since this should be found in kernel (which can't be removed), no
1351 * locking is necessary -- use preempt_disable() to placate lockdep.
1354 if (!find_symbol("module_layout", NULL
, &crc
, true, false)) {
1359 return check_version(info
, "module_layout", mod
, crc
);
1362 /* First part is kernel version, which we ignore if module has crcs. */
1363 static inline int same_magic(const char *amagic
, const char *bmagic
,
1367 amagic
+= strcspn(amagic
, " ");
1368 bmagic
+= strcspn(bmagic
, " ");
1370 return strcmp(amagic
, bmagic
) == 0;
1373 static inline int check_version(const struct load_info
*info
,
1374 const char *symname
,
1381 static inline int check_modstruct_version(const struct load_info
*info
,
1387 static inline int same_magic(const char *amagic
, const char *bmagic
,
1390 return strcmp(amagic
, bmagic
) == 0;
1392 #endif /* CONFIG_MODVERSIONS */
1394 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1395 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1396 const struct load_info
*info
,
1400 struct module
*owner
;
1401 const struct kernel_symbol
*sym
;
1406 * The module_mutex should not be a heavily contended lock;
1407 * if we get the occasional sleep here, we'll go an extra iteration
1408 * in the wait_event_interruptible(), which is harmless.
1410 sched_annotate_sleep();
1411 mutex_lock(&module_mutex
);
1412 sym
= find_symbol(name
, &owner
, &crc
,
1413 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1417 if (!check_version(info
, name
, mod
, crc
)) {
1418 sym
= ERR_PTR(-EINVAL
);
1422 err
= ref_module(mod
, owner
);
1429 /* We must make copy under the lock if we failed to get ref. */
1430 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1432 mutex_unlock(&module_mutex
);
1436 static const struct kernel_symbol
*
1437 resolve_symbol_wait(struct module
*mod
,
1438 const struct load_info
*info
,
1441 const struct kernel_symbol
*ksym
;
1442 char owner
[MODULE_NAME_LEN
];
1444 if (wait_event_interruptible_timeout(module_wq
,
1445 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1446 || PTR_ERR(ksym
) != -EBUSY
,
1448 pr_warn("%s: gave up waiting for init of module %s.\n",
1455 * /sys/module/foo/sections stuff
1456 * J. Corbet <corbet@lwn.net>
1460 #ifdef CONFIG_KALLSYMS
1461 static inline bool sect_empty(const Elf_Shdr
*sect
)
1463 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1466 struct module_sect_attr
{
1467 struct module_attribute mattr
;
1469 unsigned long address
;
1472 struct module_sect_attrs
{
1473 struct attribute_group grp
;
1474 unsigned int nsections
;
1475 struct module_sect_attr attrs
[0];
1478 static ssize_t
module_sect_show(struct module_attribute
*mattr
,
1479 struct module_kobject
*mk
, char *buf
)
1481 struct module_sect_attr
*sattr
=
1482 container_of(mattr
, struct module_sect_attr
, mattr
);
1483 return sprintf(buf
, "0x%px\n", kptr_restrict
< 2 ?
1484 (void *)sattr
->address
: NULL
);
1487 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1489 unsigned int section
;
1491 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1492 kfree(sect_attrs
->attrs
[section
].name
);
1496 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1498 unsigned int nloaded
= 0, i
, size
[2];
1499 struct module_sect_attrs
*sect_attrs
;
1500 struct module_sect_attr
*sattr
;
1501 struct attribute
**gattr
;
1503 /* Count loaded sections and allocate structures */
1504 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1505 if (!sect_empty(&info
->sechdrs
[i
]))
1507 size
[0] = ALIGN(struct_size(sect_attrs
, attrs
, nloaded
),
1508 sizeof(sect_attrs
->grp
.attrs
[0]));
1509 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.attrs
[0]);
1510 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1511 if (sect_attrs
== NULL
)
1514 /* Setup section attributes. */
1515 sect_attrs
->grp
.name
= "sections";
1516 sect_attrs
->grp
.attrs
= (void *)sect_attrs
+ size
[0];
1518 sect_attrs
->nsections
= 0;
1519 sattr
= §_attrs
->attrs
[0];
1520 gattr
= §_attrs
->grp
.attrs
[0];
1521 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1522 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1523 if (sect_empty(sec
))
1525 sattr
->address
= sec
->sh_addr
;
1526 sattr
->name
= kstrdup(info
->secstrings
+ sec
->sh_name
,
1528 if (sattr
->name
== NULL
)
1530 sect_attrs
->nsections
++;
1531 sysfs_attr_init(&sattr
->mattr
.attr
);
1532 sattr
->mattr
.show
= module_sect_show
;
1533 sattr
->mattr
.store
= NULL
;
1534 sattr
->mattr
.attr
.name
= sattr
->name
;
1535 sattr
->mattr
.attr
.mode
= S_IRUSR
;
1536 *(gattr
++) = &(sattr
++)->mattr
.attr
;
1540 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1543 mod
->sect_attrs
= sect_attrs
;
1546 free_sect_attrs(sect_attrs
);
1549 static void remove_sect_attrs(struct module
*mod
)
1551 if (mod
->sect_attrs
) {
1552 sysfs_remove_group(&mod
->mkobj
.kobj
,
1553 &mod
->sect_attrs
->grp
);
1554 /* We are positive that no one is using any sect attrs
1555 * at this point. Deallocate immediately. */
1556 free_sect_attrs(mod
->sect_attrs
);
1557 mod
->sect_attrs
= NULL
;
1562 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1565 struct module_notes_attrs
{
1566 struct kobject
*dir
;
1568 struct bin_attribute attrs
[0];
1571 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1572 struct bin_attribute
*bin_attr
,
1573 char *buf
, loff_t pos
, size_t count
)
1576 * The caller checked the pos and count against our size.
1578 memcpy(buf
, bin_attr
->private + pos
, count
);
1582 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1585 if (notes_attrs
->dir
) {
1587 sysfs_remove_bin_file(notes_attrs
->dir
,
1588 ¬es_attrs
->attrs
[i
]);
1589 kobject_put(notes_attrs
->dir
);
1594 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1596 unsigned int notes
, loaded
, i
;
1597 struct module_notes_attrs
*notes_attrs
;
1598 struct bin_attribute
*nattr
;
1600 /* failed to create section attributes, so can't create notes */
1601 if (!mod
->sect_attrs
)
1604 /* Count notes sections and allocate structures. */
1606 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1607 if (!sect_empty(&info
->sechdrs
[i
]) &&
1608 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1614 notes_attrs
= kzalloc(struct_size(notes_attrs
, attrs
, notes
),
1616 if (notes_attrs
== NULL
)
1619 notes_attrs
->notes
= notes
;
1620 nattr
= ¬es_attrs
->attrs
[0];
1621 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1622 if (sect_empty(&info
->sechdrs
[i
]))
1624 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1625 sysfs_bin_attr_init(nattr
);
1626 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].name
;
1627 nattr
->attr
.mode
= S_IRUGO
;
1628 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1629 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1630 nattr
->read
= module_notes_read
;
1636 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1637 if (!notes_attrs
->dir
)
1640 for (i
= 0; i
< notes
; ++i
)
1641 if (sysfs_create_bin_file(notes_attrs
->dir
,
1642 ¬es_attrs
->attrs
[i
]))
1645 mod
->notes_attrs
= notes_attrs
;
1649 free_notes_attrs(notes_attrs
, i
);
1652 static void remove_notes_attrs(struct module
*mod
)
1654 if (mod
->notes_attrs
)
1655 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1660 static inline void add_sect_attrs(struct module
*mod
,
1661 const struct load_info
*info
)
1665 static inline void remove_sect_attrs(struct module
*mod
)
1669 static inline void add_notes_attrs(struct module
*mod
,
1670 const struct load_info
*info
)
1674 static inline void remove_notes_attrs(struct module
*mod
)
1677 #endif /* CONFIG_KALLSYMS */
1679 static void del_usage_links(struct module
*mod
)
1681 #ifdef CONFIG_MODULE_UNLOAD
1682 struct module_use
*use
;
1684 mutex_lock(&module_mutex
);
1685 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1686 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1687 mutex_unlock(&module_mutex
);
1691 static int add_usage_links(struct module
*mod
)
1694 #ifdef CONFIG_MODULE_UNLOAD
1695 struct module_use
*use
;
1697 mutex_lock(&module_mutex
);
1698 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1699 ret
= sysfs_create_link(use
->target
->holders_dir
,
1700 &mod
->mkobj
.kobj
, mod
->name
);
1704 mutex_unlock(&module_mutex
);
1706 del_usage_links(mod
);
1711 static int module_add_modinfo_attrs(struct module
*mod
)
1713 struct module_attribute
*attr
;
1714 struct module_attribute
*temp_attr
;
1718 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1719 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1721 if (!mod
->modinfo_attrs
)
1724 temp_attr
= mod
->modinfo_attrs
;
1725 for (i
= 0; (attr
= modinfo_attrs
[i
]) && !error
; i
++) {
1726 if (!attr
->test
|| attr
->test(mod
)) {
1727 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1728 sysfs_attr_init(&temp_attr
->attr
);
1729 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1737 static void module_remove_modinfo_attrs(struct module
*mod
)
1739 struct module_attribute
*attr
;
1742 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1743 /* pick a field to test for end of list */
1744 if (!attr
->attr
.name
)
1746 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1750 kfree(mod
->modinfo_attrs
);
1753 static void mod_kobject_put(struct module
*mod
)
1755 DECLARE_COMPLETION_ONSTACK(c
);
1756 mod
->mkobj
.kobj_completion
= &c
;
1757 kobject_put(&mod
->mkobj
.kobj
);
1758 wait_for_completion(&c
);
1761 static int mod_sysfs_init(struct module
*mod
)
1764 struct kobject
*kobj
;
1766 if (!module_sysfs_initialized
) {
1767 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1772 kobj
= kset_find_obj(module_kset
, mod
->name
);
1774 pr_err("%s: module is already loaded\n", mod
->name
);
1780 mod
->mkobj
.mod
= mod
;
1782 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1783 mod
->mkobj
.kobj
.kset
= module_kset
;
1784 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1787 mod_kobject_put(mod
);
1789 /* delay uevent until full sysfs population */
1794 static int mod_sysfs_setup(struct module
*mod
,
1795 const struct load_info
*info
,
1796 struct kernel_param
*kparam
,
1797 unsigned int num_params
)
1801 err
= mod_sysfs_init(mod
);
1805 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1806 if (!mod
->holders_dir
) {
1811 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1813 goto out_unreg_holders
;
1815 err
= module_add_modinfo_attrs(mod
);
1817 goto out_unreg_param
;
1819 err
= add_usage_links(mod
);
1821 goto out_unreg_modinfo_attrs
;
1823 add_sect_attrs(mod
, info
);
1824 add_notes_attrs(mod
, info
);
1826 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1829 out_unreg_modinfo_attrs
:
1830 module_remove_modinfo_attrs(mod
);
1832 module_param_sysfs_remove(mod
);
1834 kobject_put(mod
->holders_dir
);
1836 mod_kobject_put(mod
);
1841 static void mod_sysfs_fini(struct module
*mod
)
1843 remove_notes_attrs(mod
);
1844 remove_sect_attrs(mod
);
1845 mod_kobject_put(mod
);
1848 static void init_param_lock(struct module
*mod
)
1850 mutex_init(&mod
->param_lock
);
1852 #else /* !CONFIG_SYSFS */
1854 static int mod_sysfs_setup(struct module
*mod
,
1855 const struct load_info
*info
,
1856 struct kernel_param
*kparam
,
1857 unsigned int num_params
)
1862 static void mod_sysfs_fini(struct module
*mod
)
1866 static void module_remove_modinfo_attrs(struct module
*mod
)
1870 static void del_usage_links(struct module
*mod
)
1874 static void init_param_lock(struct module
*mod
)
1877 #endif /* CONFIG_SYSFS */
1879 static void mod_sysfs_teardown(struct module
*mod
)
1881 del_usage_links(mod
);
1882 module_remove_modinfo_attrs(mod
);
1883 module_param_sysfs_remove(mod
);
1884 kobject_put(mod
->mkobj
.drivers_dir
);
1885 kobject_put(mod
->holders_dir
);
1886 mod_sysfs_fini(mod
);
1889 #ifdef CONFIG_STRICT_MODULE_RWX
1891 * LKM RO/NX protection: protect module's text/ro-data
1892 * from modification and any data from execution.
1894 * General layout of module is:
1895 * [text] [read-only-data] [ro-after-init] [writable data]
1896 * text_size -----^ ^ ^ ^
1897 * ro_size ------------------------| | |
1898 * ro_after_init_size -----------------------------| |
1899 * size -----------------------------------------------------------|
1901 * These values are always page-aligned (as is base)
1903 static void frob_text(const struct module_layout
*layout
,
1904 int (*set_memory
)(unsigned long start
, int num_pages
))
1906 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1907 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1908 set_memory((unsigned long)layout
->base
,
1909 layout
->text_size
>> PAGE_SHIFT
);
1912 static void frob_rodata(const struct module_layout
*layout
,
1913 int (*set_memory
)(unsigned long start
, int num_pages
))
1915 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1916 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1917 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1918 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
1919 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
1922 static void frob_ro_after_init(const struct module_layout
*layout
,
1923 int (*set_memory
)(unsigned long start
, int num_pages
))
1925 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1926 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1927 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1928 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
1929 (layout
->ro_after_init_size
- layout
->ro_size
) >> PAGE_SHIFT
);
1932 static void frob_writable_data(const struct module_layout
*layout
,
1933 int (*set_memory
)(unsigned long start
, int num_pages
))
1935 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1936 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1937 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
1938 set_memory((unsigned long)layout
->base
+ layout
->ro_after_init_size
,
1939 (layout
->size
- layout
->ro_after_init_size
) >> PAGE_SHIFT
);
1942 /* livepatching wants to disable read-only so it can frob module. */
1943 void module_disable_ro(const struct module
*mod
)
1945 if (!rodata_enabled
)
1948 frob_text(&mod
->core_layout
, set_memory_rw
);
1949 frob_rodata(&mod
->core_layout
, set_memory_rw
);
1950 frob_ro_after_init(&mod
->core_layout
, set_memory_rw
);
1951 frob_text(&mod
->init_layout
, set_memory_rw
);
1952 frob_rodata(&mod
->init_layout
, set_memory_rw
);
1955 void module_enable_ro(const struct module
*mod
, bool after_init
)
1957 if (!rodata_enabled
)
1960 set_vm_flush_reset_perms(mod
->core_layout
.base
);
1961 set_vm_flush_reset_perms(mod
->init_layout
.base
);
1962 frob_text(&mod
->core_layout
, set_memory_ro
);
1963 frob_text(&mod
->core_layout
, set_memory_x
);
1965 frob_rodata(&mod
->core_layout
, set_memory_ro
);
1967 frob_text(&mod
->init_layout
, set_memory_ro
);
1968 frob_text(&mod
->init_layout
, set_memory_x
);
1970 frob_rodata(&mod
->init_layout
, set_memory_ro
);
1973 frob_ro_after_init(&mod
->core_layout
, set_memory_ro
);
1976 static void module_enable_nx(const struct module
*mod
)
1978 frob_rodata(&mod
->core_layout
, set_memory_nx
);
1979 frob_ro_after_init(&mod
->core_layout
, set_memory_nx
);
1980 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
1981 frob_rodata(&mod
->init_layout
, set_memory_nx
);
1982 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
1985 /* Iterate through all modules and set each module's text as RW */
1986 void set_all_modules_text_rw(void)
1990 if (!rodata_enabled
)
1993 mutex_lock(&module_mutex
);
1994 list_for_each_entry_rcu(mod
, &modules
, list
) {
1995 if (mod
->state
== MODULE_STATE_UNFORMED
)
1998 frob_text(&mod
->core_layout
, set_memory_rw
);
1999 frob_text(&mod
->init_layout
, set_memory_rw
);
2001 mutex_unlock(&module_mutex
);
2004 /* Iterate through all modules and set each module's text as RO */
2005 void set_all_modules_text_ro(void)
2009 if (!rodata_enabled
)
2012 mutex_lock(&module_mutex
);
2013 list_for_each_entry_rcu(mod
, &modules
, list
) {
2015 * Ignore going modules since it's possible that ro
2016 * protection has already been disabled, otherwise we'll
2017 * run into protection faults at module deallocation.
2019 if (mod
->state
== MODULE_STATE_UNFORMED
||
2020 mod
->state
== MODULE_STATE_GOING
)
2023 frob_text(&mod
->core_layout
, set_memory_ro
);
2024 frob_text(&mod
->init_layout
, set_memory_ro
);
2026 mutex_unlock(&module_mutex
);
2029 static void module_enable_nx(const struct module
*mod
) { }
2032 #ifdef CONFIG_LIVEPATCH
2034 * Persist Elf information about a module. Copy the Elf header,
2035 * section header table, section string table, and symtab section
2036 * index from info to mod->klp_info.
2038 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2040 unsigned int size
, symndx
;
2043 size
= sizeof(*mod
->klp_info
);
2044 mod
->klp_info
= kmalloc(size
, GFP_KERNEL
);
2045 if (mod
->klp_info
== NULL
)
2049 size
= sizeof(mod
->klp_info
->hdr
);
2050 memcpy(&mod
->klp_info
->hdr
, info
->hdr
, size
);
2052 /* Elf section header table */
2053 size
= sizeof(*info
->sechdrs
) * info
->hdr
->e_shnum
;
2054 mod
->klp_info
->sechdrs
= kmemdup(info
->sechdrs
, size
, GFP_KERNEL
);
2055 if (mod
->klp_info
->sechdrs
== NULL
) {
2060 /* Elf section name string table */
2061 size
= info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_size
;
2062 mod
->klp_info
->secstrings
= kmemdup(info
->secstrings
, size
, GFP_KERNEL
);
2063 if (mod
->klp_info
->secstrings
== NULL
) {
2068 /* Elf symbol section index */
2069 symndx
= info
->index
.sym
;
2070 mod
->klp_info
->symndx
= symndx
;
2073 * For livepatch modules, core_kallsyms.symtab is a complete
2074 * copy of the original symbol table. Adjust sh_addr to point
2075 * to core_kallsyms.symtab since the copy of the symtab in module
2076 * init memory is freed at the end of do_init_module().
2078 mod
->klp_info
->sechdrs
[symndx
].sh_addr
= \
2079 (unsigned long) mod
->core_kallsyms
.symtab
;
2084 kfree(mod
->klp_info
->sechdrs
);
2086 kfree(mod
->klp_info
);
2090 static void free_module_elf(struct module
*mod
)
2092 kfree(mod
->klp_info
->sechdrs
);
2093 kfree(mod
->klp_info
->secstrings
);
2094 kfree(mod
->klp_info
);
2096 #else /* !CONFIG_LIVEPATCH */
2097 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2102 static void free_module_elf(struct module
*mod
)
2105 #endif /* CONFIG_LIVEPATCH */
2107 void __weak
module_memfree(void *module_region
)
2110 * This memory may be RO, and freeing RO memory in an interrupt is not
2111 * supported by vmalloc.
2113 WARN_ON(in_interrupt());
2114 vfree(module_region
);
2117 void __weak
module_arch_cleanup(struct module
*mod
)
2121 void __weak
module_arch_freeing_init(struct module
*mod
)
2125 /* Free a module, remove from lists, etc. */
2126 static void free_module(struct module
*mod
)
2128 trace_module_free(mod
);
2130 mod_sysfs_teardown(mod
);
2132 /* We leave it in list to prevent duplicate loads, but make sure
2133 * that noone uses it while it's being deconstructed. */
2134 mutex_lock(&module_mutex
);
2135 mod
->state
= MODULE_STATE_UNFORMED
;
2136 mutex_unlock(&module_mutex
);
2138 /* Remove dynamic debug info */
2139 ddebug_remove_module(mod
->name
);
2141 /* Arch-specific cleanup. */
2142 module_arch_cleanup(mod
);
2144 /* Module unload stuff */
2145 module_unload_free(mod
);
2147 /* Free any allocated parameters. */
2148 destroy_params(mod
->kp
, mod
->num_kp
);
2150 if (is_livepatch_module(mod
))
2151 free_module_elf(mod
);
2153 /* Now we can delete it from the lists */
2154 mutex_lock(&module_mutex
);
2155 /* Unlink carefully: kallsyms could be walking list. */
2156 list_del_rcu(&mod
->list
);
2157 mod_tree_remove(mod
);
2158 /* Remove this module from bug list, this uses list_del_rcu */
2159 module_bug_cleanup(mod
);
2160 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2162 mutex_unlock(&module_mutex
);
2164 /* This may be empty, but that's OK */
2165 module_arch_freeing_init(mod
);
2166 module_memfree(mod
->init_layout
.base
);
2168 percpu_modfree(mod
);
2170 /* Free lock-classes; relies on the preceding sync_rcu(). */
2171 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2173 /* Finally, free the core (containing the module structure) */
2174 module_memfree(mod
->core_layout
.base
);
2177 void *__symbol_get(const char *symbol
)
2179 struct module
*owner
;
2180 const struct kernel_symbol
*sym
;
2183 sym
= find_symbol(symbol
, &owner
, NULL
, true, true);
2184 if (sym
&& strong_try_module_get(owner
))
2188 return sym
? (void *)kernel_symbol_value(sym
) : NULL
;
2190 EXPORT_SYMBOL_GPL(__symbol_get
);
2193 * Ensure that an exported symbol [global namespace] does not already exist
2194 * in the kernel or in some other module's exported symbol table.
2196 * You must hold the module_mutex.
2198 static int verify_exported_symbols(struct module
*mod
)
2201 struct module
*owner
;
2202 const struct kernel_symbol
*s
;
2204 const struct kernel_symbol
*sym
;
2207 { mod
->syms
, mod
->num_syms
},
2208 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2209 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2210 #ifdef CONFIG_UNUSED_SYMBOLS
2211 { mod
->unused_syms
, mod
->num_unused_syms
},
2212 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2216 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2217 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2218 if (find_symbol(kernel_symbol_name(s
), &owner
, NULL
,
2220 pr_err("%s: exports duplicate symbol %s"
2222 mod
->name
, kernel_symbol_name(s
),
2223 module_name(owner
));
2231 /* Change all symbols so that st_value encodes the pointer directly. */
2232 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2234 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2235 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2236 unsigned long secbase
;
2239 const struct kernel_symbol
*ksym
;
2241 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2242 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2244 switch (sym
[i
].st_shndx
) {
2246 /* Ignore common symbols */
2247 if (!strncmp(name
, "__gnu_lto", 9))
2250 /* We compiled with -fno-common. These are not
2251 supposed to happen. */
2252 pr_debug("Common symbol: %s\n", name
);
2253 pr_warn("%s: please compile with -fno-common\n",
2259 /* Don't need to do anything */
2260 pr_debug("Absolute symbol: 0x%08lx\n",
2261 (long)sym
[i
].st_value
);
2265 /* Livepatch symbols are resolved by livepatch */
2269 ksym
= resolve_symbol_wait(mod
, info
, name
);
2270 /* Ok if resolved. */
2271 if (ksym
&& !IS_ERR(ksym
)) {
2272 sym
[i
].st_value
= kernel_symbol_value(ksym
);
2277 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2280 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2281 pr_warn("%s: Unknown symbol %s (err %d)\n",
2282 mod
->name
, name
, ret
);
2286 /* Divert to percpu allocation if a percpu var. */
2287 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2288 secbase
= (unsigned long)mod_percpu(mod
);
2290 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2291 sym
[i
].st_value
+= secbase
;
2299 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2304 /* Now do relocations. */
2305 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2306 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2308 /* Not a valid relocation section? */
2309 if (infosec
>= info
->hdr
->e_shnum
)
2312 /* Don't bother with non-allocated sections */
2313 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2316 /* Livepatch relocation sections are applied by livepatch */
2317 if (info
->sechdrs
[i
].sh_flags
& SHF_RELA_LIVEPATCH
)
2320 if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2321 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2322 info
->index
.sym
, i
, mod
);
2323 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2324 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2325 info
->index
.sym
, i
, mod
);
2332 /* Additional bytes needed by arch in front of individual sections */
2333 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2334 unsigned int section
)
2336 /* default implementation just returns zero */
2340 /* Update size with this section: return offset. */
2341 static long get_offset(struct module
*mod
, unsigned int *size
,
2342 Elf_Shdr
*sechdr
, unsigned int section
)
2346 *size
+= arch_mod_section_prepend(mod
, section
);
2347 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2348 *size
= ret
+ sechdr
->sh_size
;
2352 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2353 might -- code, read-only data, read-write data, small data. Tally
2354 sizes, and place the offsets into sh_entsize fields: high bit means it
2356 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2358 static unsigned long const masks
[][2] = {
2359 /* NOTE: all executable code must be the first section
2360 * in this array; otherwise modify the text_size
2361 * finder in the two loops below */
2362 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2363 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2364 { SHF_RO_AFTER_INIT
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2365 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2366 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2370 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2371 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2373 pr_debug("Core section allocation order:\n");
2374 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2375 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2376 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2377 const char *sname
= info
->secstrings
+ s
->sh_name
;
2379 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2380 || (s
->sh_flags
& masks
[m
][1])
2381 || s
->sh_entsize
!= ~0UL
2382 || strstarts(sname
, ".init"))
2384 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2385 pr_debug("\t%s\n", sname
);
2388 case 0: /* executable */
2389 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2390 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2392 case 1: /* RO: text and ro-data */
2393 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2394 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2396 case 2: /* RO after init */
2397 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2398 mod
->core_layout
.ro_after_init_size
= mod
->core_layout
.size
;
2400 case 4: /* whole core */
2401 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2406 pr_debug("Init section allocation order:\n");
2407 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2408 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2409 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2410 const char *sname
= info
->secstrings
+ s
->sh_name
;
2412 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2413 || (s
->sh_flags
& masks
[m
][1])
2414 || s
->sh_entsize
!= ~0UL
2415 || !strstarts(sname
, ".init"))
2417 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2418 | INIT_OFFSET_MASK
);
2419 pr_debug("\t%s\n", sname
);
2422 case 0: /* executable */
2423 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2424 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2426 case 1: /* RO: text and ro-data */
2427 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2428 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2432 * RO after init doesn't apply to init_layout (only
2433 * core_layout), so it just takes the value of ro_size.
2435 mod
->init_layout
.ro_after_init_size
= mod
->init_layout
.ro_size
;
2437 case 4: /* whole init */
2438 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2444 static void set_license(struct module
*mod
, const char *license
)
2447 license
= "unspecified";
2449 if (!license_is_gpl_compatible(license
)) {
2450 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2451 pr_warn("%s: module license '%s' taints kernel.\n",
2452 mod
->name
, license
);
2453 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2454 LOCKDEP_NOW_UNRELIABLE
);
2458 /* Parse tag=value strings from .modinfo section */
2459 static char *next_string(char *string
, unsigned long *secsize
)
2461 /* Skip non-zero chars */
2464 if ((*secsize
)-- <= 1)
2468 /* Skip any zero padding. */
2469 while (!string
[0]) {
2471 if ((*secsize
)-- <= 1)
2477 static char *get_modinfo(struct load_info
*info
, const char *tag
)
2480 unsigned int taglen
= strlen(tag
);
2481 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2482 unsigned long size
= infosec
->sh_size
;
2485 * get_modinfo() calls made before rewrite_section_headers()
2486 * must use sh_offset, as sh_addr isn't set!
2488 for (p
= (char *)info
->hdr
+ infosec
->sh_offset
; p
; p
= next_string(p
, &size
)) {
2489 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2490 return p
+ taglen
+ 1;
2495 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2497 struct module_attribute
*attr
;
2500 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2502 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2506 static void free_modinfo(struct module
*mod
)
2508 struct module_attribute
*attr
;
2511 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2517 #ifdef CONFIG_KALLSYMS
2519 /* Lookup exported symbol in given range of kernel_symbols */
2520 static const struct kernel_symbol
*lookup_exported_symbol(const char *name
,
2521 const struct kernel_symbol
*start
,
2522 const struct kernel_symbol
*stop
)
2524 return bsearch(name
, start
, stop
- start
,
2525 sizeof(struct kernel_symbol
), cmp_name
);
2528 static int is_exported(const char *name
, unsigned long value
,
2529 const struct module
*mod
)
2531 const struct kernel_symbol
*ks
;
2533 ks
= lookup_exported_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2535 ks
= lookup_exported_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2537 return ks
!= NULL
&& kernel_symbol_value(ks
) == value
;
2541 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2543 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2545 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2546 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2551 if (sym
->st_shndx
== SHN_UNDEF
)
2553 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2555 if (sym
->st_shndx
>= SHN_LORESERVE
)
2557 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2559 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2560 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2561 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2563 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2568 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2569 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2574 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2581 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2582 unsigned int shnum
, unsigned int pcpundx
)
2584 const Elf_Shdr
*sec
;
2586 if (src
->st_shndx
== SHN_UNDEF
2587 || src
->st_shndx
>= shnum
2591 #ifdef CONFIG_KALLSYMS_ALL
2592 if (src
->st_shndx
== pcpundx
)
2596 sec
= sechdrs
+ src
->st_shndx
;
2597 if (!(sec
->sh_flags
& SHF_ALLOC
)
2598 #ifndef CONFIG_KALLSYMS_ALL
2599 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2601 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2608 * We only allocate and copy the strings needed by the parts of symtab
2609 * we keep. This is simple, but has the effect of making multiple
2610 * copies of duplicates. We could be more sophisticated, see
2611 * linux-kernel thread starting with
2612 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2614 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2616 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2617 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2619 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2621 /* Put symbol section at end of init part of module. */
2622 symsect
->sh_flags
|= SHF_ALLOC
;
2623 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2624 info
->index
.sym
) | INIT_OFFSET_MASK
;
2625 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2627 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2628 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2630 /* Compute total space required for the core symbols' strtab. */
2631 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2632 if (i
== 0 || is_livepatch_module(mod
) ||
2633 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2634 info
->index
.pcpu
)) {
2635 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2640 /* Append room for core symbols at end of core part. */
2641 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2642 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2643 mod
->core_layout
.size
+= strtab_size
;
2644 info
->core_typeoffs
= mod
->core_layout
.size
;
2645 mod
->core_layout
.size
+= ndst
* sizeof(char);
2646 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2648 /* Put string table section at end of init part of module. */
2649 strsect
->sh_flags
|= SHF_ALLOC
;
2650 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2651 info
->index
.str
) | INIT_OFFSET_MASK
;
2652 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2654 /* We'll tack temporary mod_kallsyms on the end. */
2655 mod
->init_layout
.size
= ALIGN(mod
->init_layout
.size
,
2656 __alignof__(struct mod_kallsyms
));
2657 info
->mod_kallsyms_init_off
= mod
->init_layout
.size
;
2658 mod
->init_layout
.size
+= sizeof(struct mod_kallsyms
);
2659 info
->init_typeoffs
= mod
->init_layout
.size
;
2660 mod
->init_layout
.size
+= nsrc
* sizeof(char);
2661 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2665 * We use the full symtab and strtab which layout_symtab arranged to
2666 * be appended to the init section. Later we switch to the cut-down
2669 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2671 unsigned int i
, ndst
;
2675 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2677 /* Set up to point into init section. */
2678 mod
->kallsyms
= mod
->init_layout
.base
+ info
->mod_kallsyms_init_off
;
2680 mod
->kallsyms
->symtab
= (void *)symsec
->sh_addr
;
2681 mod
->kallsyms
->num_symtab
= symsec
->sh_size
/ sizeof(Elf_Sym
);
2682 /* Make sure we get permanent strtab: don't use info->strtab. */
2683 mod
->kallsyms
->strtab
= (void *)info
->sechdrs
[info
->index
.str
].sh_addr
;
2684 mod
->kallsyms
->typetab
= mod
->init_layout
.base
+ info
->init_typeoffs
;
2687 * Now populate the cut down core kallsyms for after init
2688 * and set types up while we still have access to sections.
2690 mod
->core_kallsyms
.symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2691 mod
->core_kallsyms
.strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2692 mod
->core_kallsyms
.typetab
= mod
->core_layout
.base
+ info
->core_typeoffs
;
2693 src
= mod
->kallsyms
->symtab
;
2694 for (ndst
= i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++) {
2695 mod
->kallsyms
->typetab
[i
] = elf_type(src
+ i
, info
);
2696 if (i
== 0 || is_livepatch_module(mod
) ||
2697 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2698 info
->index
.pcpu
)) {
2699 mod
->core_kallsyms
.typetab
[ndst
] =
2700 mod
->kallsyms
->typetab
[i
];
2702 dst
[ndst
++].st_name
= s
- mod
->core_kallsyms
.strtab
;
2703 s
+= strlcpy(s
, &mod
->kallsyms
->strtab
[src
[i
].st_name
],
2707 mod
->core_kallsyms
.num_symtab
= ndst
;
2710 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2714 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2717 #endif /* CONFIG_KALLSYMS */
2719 static void dynamic_debug_setup(struct module
*mod
, struct _ddebug
*debug
, unsigned int num
)
2723 ddebug_add_module(debug
, num
, mod
->name
);
2726 static void dynamic_debug_remove(struct module
*mod
, struct _ddebug
*debug
)
2729 ddebug_remove_module(mod
->name
);
2732 void * __weak
module_alloc(unsigned long size
)
2734 return vmalloc_exec(size
);
2737 #ifdef CONFIG_DEBUG_KMEMLEAK
2738 static void kmemleak_load_module(const struct module
*mod
,
2739 const struct load_info
*info
)
2743 /* only scan the sections containing data */
2744 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2746 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2747 /* Scan all writable sections that's not executable */
2748 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2749 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2750 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2753 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2754 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2758 static inline void kmemleak_load_module(const struct module
*mod
,
2759 const struct load_info
*info
)
2764 #ifdef CONFIG_MODULE_SIG
2765 static int module_sig_check(struct load_info
*info
, int flags
)
2768 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2769 const void *mod
= info
->hdr
;
2772 * Require flags == 0, as a module with version information
2773 * removed is no longer the module that was signed
2776 info
->len
> markerlen
&&
2777 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2778 /* We truncate the module to discard the signature */
2779 info
->len
-= markerlen
;
2780 err
= mod_verify_sig(mod
, info
);
2784 info
->sig_ok
= true;
2788 /* Not having a signature is only an error if we're strict. */
2789 if (err
== -ENOKEY
&& !is_module_sig_enforced())
2794 #else /* !CONFIG_MODULE_SIG */
2795 static int module_sig_check(struct load_info
*info
, int flags
)
2799 #endif /* !CONFIG_MODULE_SIG */
2801 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2802 static int elf_header_check(struct load_info
*info
)
2804 if (info
->len
< sizeof(*(info
->hdr
)))
2807 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2808 || info
->hdr
->e_type
!= ET_REL
2809 || !elf_check_arch(info
->hdr
)
2810 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2813 if (info
->hdr
->e_shoff
>= info
->len
2814 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2815 info
->len
- info
->hdr
->e_shoff
))
2821 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2823 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2826 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2828 if (copy_from_user(dst
, usrc
, n
) != 0)
2838 #ifdef CONFIG_LIVEPATCH
2839 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2841 if (get_modinfo(info
, "livepatch")) {
2843 add_taint_module(mod
, TAINT_LIVEPATCH
, LOCKDEP_STILL_OK
);
2844 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2850 #else /* !CONFIG_LIVEPATCH */
2851 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2853 if (get_modinfo(info
, "livepatch")) {
2854 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2861 #endif /* CONFIG_LIVEPATCH */
2863 static void check_modinfo_retpoline(struct module
*mod
, struct load_info
*info
)
2865 if (retpoline_module_ok(get_modinfo(info
, "retpoline")))
2868 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
2872 /* Sets info->hdr and info->len. */
2873 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
2874 struct load_info
*info
)
2879 if (info
->len
< sizeof(*(info
->hdr
)))
2882 err
= security_kernel_load_data(LOADING_MODULE
);
2886 /* Suck in entire file: we'll want most of it. */
2887 info
->hdr
= __vmalloc(info
->len
,
2888 GFP_KERNEL
| __GFP_NOWARN
, PAGE_KERNEL
);
2892 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
2900 static void free_copy(struct load_info
*info
)
2905 static int rewrite_section_headers(struct load_info
*info
, int flags
)
2909 /* This should always be true, but let's be sure. */
2910 info
->sechdrs
[0].sh_addr
= 0;
2912 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2913 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
2914 if (shdr
->sh_type
!= SHT_NOBITS
2915 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
2916 pr_err("Module len %lu truncated\n", info
->len
);
2920 /* Mark all sections sh_addr with their address in the
2922 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
2924 #ifndef CONFIG_MODULE_UNLOAD
2925 /* Don't load .exit sections */
2926 if (strstarts(info
->secstrings
+shdr
->sh_name
, ".exit"))
2927 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2931 /* Track but don't keep modinfo and version sections. */
2932 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2933 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2939 * Set up our basic convenience variables (pointers to section headers,
2940 * search for module section index etc), and do some basic section
2943 * Set info->mod to the temporary copy of the module in info->hdr. The final one
2944 * will be allocated in move_module().
2946 static int setup_load_info(struct load_info
*info
, int flags
)
2950 /* Set up the convenience variables */
2951 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
2952 info
->secstrings
= (void *)info
->hdr
2953 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
2955 /* Try to find a name early so we can log errors with a module name */
2956 info
->index
.info
= find_sec(info
, ".modinfo");
2957 if (!info
->index
.info
)
2958 info
->name
= "(missing .modinfo section)";
2960 info
->name
= get_modinfo(info
, "name");
2962 /* Find internal symbols and strings. */
2963 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2964 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
2965 info
->index
.sym
= i
;
2966 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
2967 info
->strtab
= (char *)info
->hdr
2968 + info
->sechdrs
[info
->index
.str
].sh_offset
;
2973 if (info
->index
.sym
== 0) {
2974 pr_warn("%s: module has no symbols (stripped?)\n", info
->name
);
2978 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
2979 if (!info
->index
.mod
) {
2980 pr_warn("%s: No module found in object\n",
2981 info
->name
?: "(missing .modinfo name field)");
2984 /* This is temporary: point mod into copy of data. */
2985 info
->mod
= (void *)info
->hdr
+ info
->sechdrs
[info
->index
.mod
].sh_offset
;
2988 * If we didn't load the .modinfo 'name' field earlier, fall back to
2989 * on-disk struct mod 'name' field.
2992 info
->name
= info
->mod
->name
;
2994 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
2995 info
->index
.vers
= 0; /* Pretend no __versions section! */
2997 info
->index
.vers
= find_sec(info
, "__versions");
2999 info
->index
.pcpu
= find_pcpusec(info
);
3004 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
3006 const char *modmagic
= get_modinfo(info
, "vermagic");
3009 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
3012 /* This is allowed: modprobe --force will invalidate it. */
3014 err
= try_to_force_load(mod
, "bad vermagic");
3017 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
3018 pr_err("%s: version magic '%s' should be '%s'\n",
3019 info
->name
, modmagic
, vermagic
);
3023 if (!get_modinfo(info
, "intree")) {
3024 if (!test_taint(TAINT_OOT_MODULE
))
3025 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3027 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
3030 check_modinfo_retpoline(mod
, info
);
3032 if (get_modinfo(info
, "staging")) {
3033 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
3034 pr_warn("%s: module is from the staging directory, the quality "
3035 "is unknown, you have been warned.\n", mod
->name
);
3038 err
= check_modinfo_livepatch(mod
, info
);
3042 /* Set up license info based on the info section */
3043 set_license(mod
, get_modinfo(info
, "license"));
3048 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
3050 mod
->kp
= section_objs(info
, "__param",
3051 sizeof(*mod
->kp
), &mod
->num_kp
);
3052 mod
->syms
= section_objs(info
, "__ksymtab",
3053 sizeof(*mod
->syms
), &mod
->num_syms
);
3054 mod
->crcs
= section_addr(info
, "__kcrctab");
3055 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
3056 sizeof(*mod
->gpl_syms
),
3057 &mod
->num_gpl_syms
);
3058 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
3059 mod
->gpl_future_syms
= section_objs(info
,
3060 "__ksymtab_gpl_future",
3061 sizeof(*mod
->gpl_future_syms
),
3062 &mod
->num_gpl_future_syms
);
3063 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
3065 #ifdef CONFIG_UNUSED_SYMBOLS
3066 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
3067 sizeof(*mod
->unused_syms
),
3068 &mod
->num_unused_syms
);
3069 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
3070 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
3071 sizeof(*mod
->unused_gpl_syms
),
3072 &mod
->num_unused_gpl_syms
);
3073 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
3075 #ifdef CONFIG_CONSTRUCTORS
3076 mod
->ctors
= section_objs(info
, ".ctors",
3077 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3079 mod
->ctors
= section_objs(info
, ".init_array",
3080 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3081 else if (find_sec(info
, ".init_array")) {
3083 * This shouldn't happen with same compiler and binutils
3084 * building all parts of the module.
3086 pr_warn("%s: has both .ctors and .init_array.\n",
3092 #ifdef CONFIG_TRACEPOINTS
3093 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
3094 sizeof(*mod
->tracepoints_ptrs
),
3095 &mod
->num_tracepoints
);
3097 #ifdef CONFIG_BPF_EVENTS
3098 mod
->bpf_raw_events
= section_objs(info
, "__bpf_raw_tp_map",
3099 sizeof(*mod
->bpf_raw_events
),
3100 &mod
->num_bpf_raw_events
);
3102 #ifdef CONFIG_JUMP_LABEL
3103 mod
->jump_entries
= section_objs(info
, "__jump_table",
3104 sizeof(*mod
->jump_entries
),
3105 &mod
->num_jump_entries
);
3107 #ifdef CONFIG_EVENT_TRACING
3108 mod
->trace_events
= section_objs(info
, "_ftrace_events",
3109 sizeof(*mod
->trace_events
),
3110 &mod
->num_trace_events
);
3111 mod
->trace_evals
= section_objs(info
, "_ftrace_eval_map",
3112 sizeof(*mod
->trace_evals
),
3113 &mod
->num_trace_evals
);
3115 #ifdef CONFIG_TRACING
3116 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
3117 sizeof(*mod
->trace_bprintk_fmt_start
),
3118 &mod
->num_trace_bprintk_fmt
);
3120 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3121 /* sechdrs[0].sh_size is always zero */
3122 mod
->ftrace_callsites
= section_objs(info
, "__mcount_loc",
3123 sizeof(*mod
->ftrace_callsites
),
3124 &mod
->num_ftrace_callsites
);
3126 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
3127 mod
->ei_funcs
= section_objs(info
, "_error_injection_whitelist",
3128 sizeof(*mod
->ei_funcs
),
3129 &mod
->num_ei_funcs
);
3131 mod
->extable
= section_objs(info
, "__ex_table",
3132 sizeof(*mod
->extable
), &mod
->num_exentries
);
3134 if (section_addr(info
, "__obsparm"))
3135 pr_warn("%s: Ignoring obsolete parameters\n", mod
->name
);
3137 info
->debug
= section_objs(info
, "__verbose",
3138 sizeof(*info
->debug
), &info
->num_debug
);
3143 static int move_module(struct module
*mod
, struct load_info
*info
)
3148 /* Do the allocs. */
3149 ptr
= module_alloc(mod
->core_layout
.size
);
3151 * The pointer to this block is stored in the module structure
3152 * which is inside the block. Just mark it as not being a
3155 kmemleak_not_leak(ptr
);
3159 memset(ptr
, 0, mod
->core_layout
.size
);
3160 mod
->core_layout
.base
= ptr
;
3162 if (mod
->init_layout
.size
) {
3163 ptr
= module_alloc(mod
->init_layout
.size
);
3165 * The pointer to this block is stored in the module structure
3166 * which is inside the block. This block doesn't need to be
3167 * scanned as it contains data and code that will be freed
3168 * after the module is initialized.
3170 kmemleak_ignore(ptr
);
3172 module_memfree(mod
->core_layout
.base
);
3175 memset(ptr
, 0, mod
->init_layout
.size
);
3176 mod
->init_layout
.base
= ptr
;
3178 mod
->init_layout
.base
= NULL
;
3180 /* Transfer each section which specifies SHF_ALLOC */
3181 pr_debug("final section addresses:\n");
3182 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
3184 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3186 if (!(shdr
->sh_flags
& SHF_ALLOC
))
3189 if (shdr
->sh_entsize
& INIT_OFFSET_MASK
)
3190 dest
= mod
->init_layout
.base
3191 + (shdr
->sh_entsize
& ~INIT_OFFSET_MASK
);
3193 dest
= mod
->core_layout
.base
+ shdr
->sh_entsize
;
3195 if (shdr
->sh_type
!= SHT_NOBITS
)
3196 memcpy(dest
, (void *)shdr
->sh_addr
, shdr
->sh_size
);
3197 /* Update sh_addr to point to copy in image. */
3198 shdr
->sh_addr
= (unsigned long)dest
;
3199 pr_debug("\t0x%lx %s\n",
3200 (long)shdr
->sh_addr
, info
->secstrings
+ shdr
->sh_name
);
3206 static int check_module_license_and_versions(struct module
*mod
)
3208 int prev_taint
= test_taint(TAINT_PROPRIETARY_MODULE
);
3211 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3212 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3213 * using GPL-only symbols it needs.
3215 if (strcmp(mod
->name
, "ndiswrapper") == 0)
3216 add_taint(TAINT_PROPRIETARY_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
3218 /* driverloader was caught wrongly pretending to be under GPL */
3219 if (strcmp(mod
->name
, "driverloader") == 0)
3220 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3221 LOCKDEP_NOW_UNRELIABLE
);
3223 /* lve claims to be GPL but upstream won't provide source */
3224 if (strcmp(mod
->name
, "lve") == 0)
3225 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3226 LOCKDEP_NOW_UNRELIABLE
);
3228 if (!prev_taint
&& test_taint(TAINT_PROPRIETARY_MODULE
))
3229 pr_warn("%s: module license taints kernel.\n", mod
->name
);
3231 #ifdef CONFIG_MODVERSIONS
3232 if ((mod
->num_syms
&& !mod
->crcs
)
3233 || (mod
->num_gpl_syms
&& !mod
->gpl_crcs
)
3234 || (mod
->num_gpl_future_syms
&& !mod
->gpl_future_crcs
)
3235 #ifdef CONFIG_UNUSED_SYMBOLS
3236 || (mod
->num_unused_syms
&& !mod
->unused_crcs
)
3237 || (mod
->num_unused_gpl_syms
&& !mod
->unused_gpl_crcs
)
3240 return try_to_force_load(mod
,
3241 "no versions for exported symbols");
3247 static void flush_module_icache(const struct module
*mod
)
3249 mm_segment_t old_fs
;
3251 /* flush the icache in correct context */
3256 * Flush the instruction cache, since we've played with text.
3257 * Do it before processing of module parameters, so the module
3258 * can provide parameter accessor functions of its own.
3260 if (mod
->init_layout
.base
)
3261 flush_icache_range((unsigned long)mod
->init_layout
.base
,
3262 (unsigned long)mod
->init_layout
.base
3263 + mod
->init_layout
.size
);
3264 flush_icache_range((unsigned long)mod
->core_layout
.base
,
3265 (unsigned long)mod
->core_layout
.base
+ mod
->core_layout
.size
);
3270 int __weak
module_frob_arch_sections(Elf_Ehdr
*hdr
,
3278 /* module_blacklist is a comma-separated list of module names */
3279 static char *module_blacklist
;
3280 static bool blacklisted(const char *module_name
)
3285 if (!module_blacklist
)
3288 for (p
= module_blacklist
; *p
; p
+= len
) {
3289 len
= strcspn(p
, ",");
3290 if (strlen(module_name
) == len
&& !memcmp(module_name
, p
, len
))
3297 core_param(module_blacklist
, module_blacklist
, charp
, 0400);
3299 static struct module
*layout_and_allocate(struct load_info
*info
, int flags
)
3305 err
= check_modinfo(info
->mod
, info
, flags
);
3307 return ERR_PTR(err
);
3309 /* Allow arches to frob section contents and sizes. */
3310 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3311 info
->secstrings
, info
->mod
);
3313 return ERR_PTR(err
);
3315 /* We will do a special allocation for per-cpu sections later. */
3316 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3319 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3320 * layout_sections() can put it in the right place.
3321 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3323 ndx
= find_sec(info
, ".data..ro_after_init");
3325 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3327 * Mark the __jump_table section as ro_after_init as well: these data
3328 * structures are never modified, with the exception of entries that
3329 * refer to code in the __init section, which are annotated as such
3330 * at module load time.
3332 ndx
= find_sec(info
, "__jump_table");
3334 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3336 /* Determine total sizes, and put offsets in sh_entsize. For now
3337 this is done generically; there doesn't appear to be any
3338 special cases for the architectures. */
3339 layout_sections(info
->mod
, info
);
3340 layout_symtab(info
->mod
, info
);
3342 /* Allocate and move to the final place */
3343 err
= move_module(info
->mod
, info
);
3345 return ERR_PTR(err
);
3347 /* Module has been copied to its final place now: return it. */
3348 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3349 kmemleak_load_module(mod
, info
);
3353 /* mod is no longer valid after this! */
3354 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3356 percpu_modfree(mod
);
3357 module_arch_freeing_init(mod
);
3358 module_memfree(mod
->init_layout
.base
);
3359 module_memfree(mod
->core_layout
.base
);
3362 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3363 const Elf_Shdr
*sechdrs
,
3369 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3371 /* Sort exception table now relocations are done. */
3372 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3374 /* Copy relocated percpu area over. */
3375 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3376 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3378 /* Setup kallsyms-specific fields. */
3379 add_kallsyms(mod
, info
);
3381 /* Arch-specific module finalizing. */
3382 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3385 /* Is this module of this name done loading? No locks held. */
3386 static bool finished_loading(const char *name
)
3392 * The module_mutex should not be a heavily contended lock;
3393 * if we get the occasional sleep here, we'll go an extra iteration
3394 * in the wait_event_interruptible(), which is harmless.
3396 sched_annotate_sleep();
3397 mutex_lock(&module_mutex
);
3398 mod
= find_module_all(name
, strlen(name
), true);
3399 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
;
3400 mutex_unlock(&module_mutex
);
3405 /* Call module constructors. */
3406 static void do_mod_ctors(struct module
*mod
)
3408 #ifdef CONFIG_CONSTRUCTORS
3411 for (i
= 0; i
< mod
->num_ctors
; i
++)
3416 /* For freeing module_init on success, in case kallsyms traversing */
3417 struct mod_initfree
{
3418 struct llist_node node
;
3422 static void do_free_init(struct work_struct
*w
)
3424 struct llist_node
*pos
, *n
, *list
;
3425 struct mod_initfree
*initfree
;
3427 list
= llist_del_all(&init_free_list
);
3431 llist_for_each_safe(pos
, n
, list
) {
3432 initfree
= container_of(pos
, struct mod_initfree
, node
);
3433 module_memfree(initfree
->module_init
);
3438 static int __init
modules_wq_init(void)
3440 INIT_WORK(&init_free_wq
, do_free_init
);
3441 init_llist_head(&init_free_list
);
3444 module_init(modules_wq_init
);
3447 * This is where the real work happens.
3449 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3450 * helper command 'lx-symbols'.
3452 static noinline
int do_init_module(struct module
*mod
)
3455 struct mod_initfree
*freeinit
;
3457 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3462 freeinit
->module_init
= mod
->init_layout
.base
;
3465 * We want to find out whether @mod uses async during init. Clear
3466 * PF_USED_ASYNC. async_schedule*() will set it.
3468 current
->flags
&= ~PF_USED_ASYNC
;
3471 /* Start the module */
3472 if (mod
->init
!= NULL
)
3473 ret
= do_one_initcall(mod
->init
);
3475 goto fail_free_freeinit
;
3478 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3479 "follow 0/-E convention\n"
3480 "%s: loading module anyway...\n",
3481 __func__
, mod
->name
, ret
, __func__
);
3485 /* Now it's a first class citizen! */
3486 mod
->state
= MODULE_STATE_LIVE
;
3487 blocking_notifier_call_chain(&module_notify_list
,
3488 MODULE_STATE_LIVE
, mod
);
3491 * We need to finish all async code before the module init sequence
3492 * is done. This has potential to deadlock. For example, a newly
3493 * detected block device can trigger request_module() of the
3494 * default iosched from async probing task. Once userland helper
3495 * reaches here, async_synchronize_full() will wait on the async
3496 * task waiting on request_module() and deadlock.
3498 * This deadlock is avoided by perfomring async_synchronize_full()
3499 * iff module init queued any async jobs. This isn't a full
3500 * solution as it will deadlock the same if module loading from
3501 * async jobs nests more than once; however, due to the various
3502 * constraints, this hack seems to be the best option for now.
3503 * Please refer to the following thread for details.
3505 * http://thread.gmane.org/gmane.linux.kernel/1420814
3507 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3508 async_synchronize_full();
3510 ftrace_free_mem(mod
, mod
->init_layout
.base
, mod
->init_layout
.base
+
3511 mod
->init_layout
.size
);
3512 mutex_lock(&module_mutex
);
3513 /* Drop initial reference. */
3515 trim_init_extable(mod
);
3516 #ifdef CONFIG_KALLSYMS
3517 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3518 rcu_assign_pointer(mod
->kallsyms
, &mod
->core_kallsyms
);
3520 module_enable_ro(mod
, true);
3521 mod_tree_remove_init(mod
);
3522 module_arch_freeing_init(mod
);
3523 mod
->init_layout
.base
= NULL
;
3524 mod
->init_layout
.size
= 0;
3525 mod
->init_layout
.ro_size
= 0;
3526 mod
->init_layout
.ro_after_init_size
= 0;
3527 mod
->init_layout
.text_size
= 0;
3529 * We want to free module_init, but be aware that kallsyms may be
3530 * walking this with preempt disabled. In all the failure paths, we
3531 * call synchronize_rcu(), but we don't want to slow down the success
3532 * path. module_memfree() cannot be called in an interrupt, so do the
3533 * work and call synchronize_rcu() in a work queue.
3535 * Note that module_alloc() on most architectures creates W+X page
3536 * mappings which won't be cleaned up until do_free_init() runs. Any
3537 * code such as mark_rodata_ro() which depends on those mappings to
3538 * be cleaned up needs to sync with the queued work - ie
3541 if (llist_add(&freeinit
->node
, &init_free_list
))
3542 schedule_work(&init_free_wq
);
3544 mutex_unlock(&module_mutex
);
3545 wake_up_all(&module_wq
);
3552 /* Try to protect us from buggy refcounters. */
3553 mod
->state
= MODULE_STATE_GOING
;
3556 blocking_notifier_call_chain(&module_notify_list
,
3557 MODULE_STATE_GOING
, mod
);
3558 klp_module_going(mod
);
3559 ftrace_release_mod(mod
);
3561 wake_up_all(&module_wq
);
3565 static int may_init_module(void)
3567 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3574 * We try to place it in the list now to make sure it's unique before
3575 * we dedicate too many resources. In particular, temporary percpu
3576 * memory exhaustion.
3578 static int add_unformed_module(struct module
*mod
)
3583 mod
->state
= MODULE_STATE_UNFORMED
;
3586 mutex_lock(&module_mutex
);
3587 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3589 if (old
->state
!= MODULE_STATE_LIVE
) {
3590 /* Wait in case it fails to load. */
3591 mutex_unlock(&module_mutex
);
3592 err
= wait_event_interruptible(module_wq
,
3593 finished_loading(mod
->name
));
3601 mod_update_bounds(mod
);
3602 list_add_rcu(&mod
->list
, &modules
);
3603 mod_tree_insert(mod
);
3607 mutex_unlock(&module_mutex
);
3612 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3616 mutex_lock(&module_mutex
);
3618 /* Find duplicate symbols (must be called under lock). */
3619 err
= verify_exported_symbols(mod
);
3623 /* This relies on module_mutex for list integrity. */
3624 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3626 module_enable_ro(mod
, false);
3627 module_enable_nx(mod
);
3629 /* Mark state as coming so strong_try_module_get() ignores us,
3630 * but kallsyms etc. can see us. */
3631 mod
->state
= MODULE_STATE_COMING
;
3632 mutex_unlock(&module_mutex
);
3637 mutex_unlock(&module_mutex
);
3641 static int prepare_coming_module(struct module
*mod
)
3645 ftrace_module_enable(mod
);
3646 err
= klp_module_coming(mod
);
3650 blocking_notifier_call_chain(&module_notify_list
,
3651 MODULE_STATE_COMING
, mod
);
3655 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3658 struct module
*mod
= arg
;
3661 if (strcmp(param
, "async_probe") == 0) {
3662 mod
->async_probe_requested
= true;
3666 /* Check for magic 'dyndbg' arg */
3667 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3669 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3673 /* Allocate and load the module: note that size of section 0 is always
3674 zero, and we rely on this for optional sections. */
3675 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3682 err
= elf_header_check(info
);
3686 err
= setup_load_info(info
, flags
);
3690 if (blacklisted(info
->name
)) {
3695 err
= module_sig_check(info
, flags
);
3699 err
= rewrite_section_headers(info
, flags
);
3703 /* Check module struct version now, before we try to use module. */
3704 if (!check_modstruct_version(info
, info
->mod
)) {
3709 /* Figure out module layout, and allocate all the memory. */
3710 mod
= layout_and_allocate(info
, flags
);
3716 audit_log_kern_module(mod
->name
);
3718 /* Reserve our place in the list. */
3719 err
= add_unformed_module(mod
);
3723 #ifdef CONFIG_MODULE_SIG
3724 mod
->sig_ok
= info
->sig_ok
;
3726 pr_notice_once("%s: module verification failed: signature "
3727 "and/or required key missing - tainting "
3728 "kernel\n", mod
->name
);
3729 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3733 /* To avoid stressing percpu allocator, do this once we're unique. */
3734 err
= percpu_modalloc(mod
, info
);
3738 /* Now module is in final location, initialize linked lists, etc. */
3739 err
= module_unload_init(mod
);
3743 init_param_lock(mod
);
3745 /* Now we've got everything in the final locations, we can
3746 * find optional sections. */
3747 err
= find_module_sections(mod
, info
);
3751 err
= check_module_license_and_versions(mod
);
3755 /* Set up MODINFO_ATTR fields */
3756 setup_modinfo(mod
, info
);
3758 /* Fix up syms, so that st_value is a pointer to location. */
3759 err
= simplify_symbols(mod
, info
);
3763 err
= apply_relocations(mod
, info
);
3767 err
= post_relocation(mod
, info
);
3771 flush_module_icache(mod
);
3773 /* Now copy in args */
3774 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3775 if (IS_ERR(mod
->args
)) {
3776 err
= PTR_ERR(mod
->args
);
3777 goto free_arch_cleanup
;
3780 dynamic_debug_setup(mod
, info
->debug
, info
->num_debug
);
3782 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3783 ftrace_module_init(mod
);
3785 /* Finally it's fully formed, ready to start executing. */
3786 err
= complete_formation(mod
, info
);
3788 goto ddebug_cleanup
;
3790 err
= prepare_coming_module(mod
);
3794 /* Module is ready to execute: parsing args may do that. */
3795 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3797 unknown_module_param_cb
);
3798 if (IS_ERR(after_dashes
)) {
3799 err
= PTR_ERR(after_dashes
);
3800 goto coming_cleanup
;
3801 } else if (after_dashes
) {
3802 pr_warn("%s: parameters '%s' after `--' ignored\n",
3803 mod
->name
, after_dashes
);
3806 /* Link in to sysfs. */
3807 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3809 goto coming_cleanup
;
3811 if (is_livepatch_module(mod
)) {
3812 err
= copy_module_elf(mod
, info
);
3817 /* Get rid of temporary copy. */
3821 trace_module_load(mod
);
3823 return do_init_module(mod
);
3826 mod_sysfs_teardown(mod
);
3828 mod
->state
= MODULE_STATE_GOING
;
3829 destroy_params(mod
->kp
, mod
->num_kp
);
3830 blocking_notifier_call_chain(&module_notify_list
,
3831 MODULE_STATE_GOING
, mod
);
3832 klp_module_going(mod
);
3834 /* module_bug_cleanup needs module_mutex protection */
3835 mutex_lock(&module_mutex
);
3836 module_bug_cleanup(mod
);
3837 mutex_unlock(&module_mutex
);
3840 ftrace_release_mod(mod
);
3841 dynamic_debug_remove(mod
, info
->debug
);
3845 module_arch_cleanup(mod
);
3849 module_unload_free(mod
);
3851 mutex_lock(&module_mutex
);
3852 /* Unlink carefully: kallsyms could be walking list. */
3853 list_del_rcu(&mod
->list
);
3854 mod_tree_remove(mod
);
3855 wake_up_all(&module_wq
);
3856 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3858 mutex_unlock(&module_mutex
);
3860 /* Free lock-classes; relies on the preceding sync_rcu() */
3861 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
3863 module_deallocate(mod
, info
);
3869 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
3870 unsigned long, len
, const char __user
*, uargs
)
3873 struct load_info info
= { };
3875 err
= may_init_module();
3879 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3882 err
= copy_module_from_user(umod
, len
, &info
);
3886 return load_module(&info
, uargs
, 0);
3889 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
3891 struct load_info info
= { };
3896 err
= may_init_module();
3900 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
3902 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
3903 |MODULE_INIT_IGNORE_VERMAGIC
))
3906 err
= kernel_read_file_from_fd(fd
, &hdr
, &size
, INT_MAX
,
3913 return load_module(&info
, uargs
, flags
);
3916 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
3918 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
3921 #ifdef CONFIG_KALLSYMS
3923 * This ignores the intensely annoying "mapping symbols" found
3924 * in ARM ELF files: $a, $t and $d.
3926 static inline int is_arm_mapping_symbol(const char *str
)
3928 if (str
[0] == '.' && str
[1] == 'L')
3930 return str
[0] == '$' && strchr("axtd", str
[1])
3931 && (str
[2] == '\0' || str
[2] == '.');
3934 static const char *kallsyms_symbol_name(struct mod_kallsyms
*kallsyms
, unsigned int symnum
)
3936 return kallsyms
->strtab
+ kallsyms
->symtab
[symnum
].st_name
;
3940 * Given a module and address, find the corresponding symbol and return its name
3941 * while providing its size and offset if needed.
3943 static const char *find_kallsyms_symbol(struct module
*mod
,
3945 unsigned long *size
,
3946 unsigned long *offset
)
3948 unsigned int i
, best
= 0;
3949 unsigned long nextval
, bestval
;
3950 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
3952 /* At worse, next value is at end of module */
3953 if (within_module_init(addr
, mod
))
3954 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
3956 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
3958 bestval
= kallsyms_symbol_value(&kallsyms
->symtab
[best
]);
3960 /* Scan for closest preceding symbol, and next symbol. (ELF
3961 starts real symbols at 1). */
3962 for (i
= 1; i
< kallsyms
->num_symtab
; i
++) {
3963 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
3964 unsigned long thisval
= kallsyms_symbol_value(sym
);
3966 if (sym
->st_shndx
== SHN_UNDEF
)
3969 /* We ignore unnamed symbols: they're uninformative
3970 * and inserted at a whim. */
3971 if (*kallsyms_symbol_name(kallsyms
, i
) == '\0'
3972 || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms
, i
)))
3975 if (thisval
<= addr
&& thisval
> bestval
) {
3979 if (thisval
> addr
&& thisval
< nextval
)
3987 *size
= nextval
- bestval
;
3989 *offset
= addr
- bestval
;
3991 return kallsyms_symbol_name(kallsyms
, best
);
3994 void * __weak
dereference_module_function_descriptor(struct module
*mod
,
4000 /* For kallsyms to ask for address resolution. NULL means not found. Careful
4001 * not to lock to avoid deadlock on oopses, simply disable preemption. */
4002 const char *module_address_lookup(unsigned long addr
,
4003 unsigned long *size
,
4004 unsigned long *offset
,
4008 const char *ret
= NULL
;
4012 mod
= __module_address(addr
);
4015 *modname
= mod
->name
;
4017 ret
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4019 /* Make a copy in here where it's safe */
4021 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
4029 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
4034 list_for_each_entry_rcu(mod
, &modules
, list
) {
4035 if (mod
->state
== MODULE_STATE_UNFORMED
)
4037 if (within_module(addr
, mod
)) {
4040 sym
= find_kallsyms_symbol(mod
, addr
, NULL
, NULL
);
4044 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
4054 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
4055 unsigned long *offset
, char *modname
, char *name
)
4060 list_for_each_entry_rcu(mod
, &modules
, list
) {
4061 if (mod
->state
== MODULE_STATE_UNFORMED
)
4063 if (within_module(addr
, mod
)) {
4066 sym
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4070 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
4072 strlcpy(name
, sym
, KSYM_NAME_LEN
);
4082 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
4083 char *name
, char *module_name
, int *exported
)
4088 list_for_each_entry_rcu(mod
, &modules
, list
) {
4089 struct mod_kallsyms
*kallsyms
;
4091 if (mod
->state
== MODULE_STATE_UNFORMED
)
4093 kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4094 if (symnum
< kallsyms
->num_symtab
) {
4095 const Elf_Sym
*sym
= &kallsyms
->symtab
[symnum
];
4097 *value
= kallsyms_symbol_value(sym
);
4098 *type
= kallsyms
->typetab
[symnum
];
4099 strlcpy(name
, kallsyms_symbol_name(kallsyms
, symnum
), KSYM_NAME_LEN
);
4100 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
4101 *exported
= is_exported(name
, *value
, mod
);
4105 symnum
-= kallsyms
->num_symtab
;
4111 /* Given a module and name of symbol, find and return the symbol's value */
4112 static unsigned long find_kallsyms_symbol_value(struct module
*mod
, const char *name
)
4115 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4117 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4118 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4120 if (strcmp(name
, kallsyms_symbol_name(kallsyms
, i
)) == 0 &&
4121 sym
->st_shndx
!= SHN_UNDEF
)
4122 return kallsyms_symbol_value(sym
);
4127 /* Look for this name: can be of form module:name. */
4128 unsigned long module_kallsyms_lookup_name(const char *name
)
4132 unsigned long ret
= 0;
4134 /* Don't lock: we're in enough trouble already. */
4136 if ((colon
= strnchr(name
, MODULE_NAME_LEN
, ':')) != NULL
) {
4137 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
4138 ret
= find_kallsyms_symbol_value(mod
, colon
+1);
4140 list_for_each_entry_rcu(mod
, &modules
, list
) {
4141 if (mod
->state
== MODULE_STATE_UNFORMED
)
4143 if ((ret
= find_kallsyms_symbol_value(mod
, name
)) != 0)
4151 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
4152 struct module
*, unsigned long),
4159 module_assert_mutex();
4161 list_for_each_entry(mod
, &modules
, list
) {
4162 /* We hold module_mutex: no need for rcu_dereference_sched */
4163 struct mod_kallsyms
*kallsyms
= mod
->kallsyms
;
4165 if (mod
->state
== MODULE_STATE_UNFORMED
)
4167 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4168 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4170 if (sym
->st_shndx
== SHN_UNDEF
)
4173 ret
= fn(data
, kallsyms_symbol_name(kallsyms
, i
),
4174 mod
, kallsyms_symbol_value(sym
));
4181 #endif /* CONFIG_KALLSYMS */
4183 /* Maximum number of characters written by module_flags() */
4184 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4186 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4187 static char *module_flags(struct module
*mod
, char *buf
)
4191 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
4193 mod
->state
== MODULE_STATE_GOING
||
4194 mod
->state
== MODULE_STATE_COMING
) {
4196 bx
+= module_flags_taint(mod
, buf
+ bx
);
4197 /* Show a - for module-is-being-unloaded */
4198 if (mod
->state
== MODULE_STATE_GOING
)
4200 /* Show a + for module-is-being-loaded */
4201 if (mod
->state
== MODULE_STATE_COMING
)
4210 #ifdef CONFIG_PROC_FS
4211 /* Called by the /proc file system to return a list of modules. */
4212 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
4214 mutex_lock(&module_mutex
);
4215 return seq_list_start(&modules
, *pos
);
4218 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
4220 return seq_list_next(p
, &modules
, pos
);
4223 static void m_stop(struct seq_file
*m
, void *p
)
4225 mutex_unlock(&module_mutex
);
4228 static int m_show(struct seq_file
*m
, void *p
)
4230 struct module
*mod
= list_entry(p
, struct module
, list
);
4231 char buf
[MODULE_FLAGS_BUF_SIZE
];
4234 /* We always ignore unformed modules. */
4235 if (mod
->state
== MODULE_STATE_UNFORMED
)
4238 seq_printf(m
, "%s %u",
4239 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
4240 print_unload_info(m
, mod
);
4242 /* Informative for users. */
4243 seq_printf(m
, " %s",
4244 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
4245 mod
->state
== MODULE_STATE_COMING
? "Loading" :
4247 /* Used by oprofile and other similar tools. */
4248 value
= m
->private ? NULL
: mod
->core_layout
.base
;
4249 seq_printf(m
, " 0x%px", value
);
4253 seq_printf(m
, " %s", module_flags(mod
, buf
));
4259 /* Format: modulename size refcount deps address
4261 Where refcount is a number or -, and deps is a comma-separated list
4264 static const struct seq_operations modules_op
= {
4272 * This also sets the "private" pointer to non-NULL if the
4273 * kernel pointers should be hidden (so you can just test
4274 * "m->private" to see if you should keep the values private).
4276 * We use the same logic as for /proc/kallsyms.
4278 static int modules_open(struct inode
*inode
, struct file
*file
)
4280 int err
= seq_open(file
, &modules_op
);
4283 struct seq_file
*m
= file
->private_data
;
4284 m
->private = kallsyms_show_value() ? NULL
: (void *)8ul;
4290 static const struct file_operations proc_modules_operations
= {
4291 .open
= modules_open
,
4293 .llseek
= seq_lseek
,
4294 .release
= seq_release
,
4297 static int __init
proc_modules_init(void)
4299 proc_create("modules", 0, NULL
, &proc_modules_operations
);
4302 module_init(proc_modules_init
);
4305 /* Given an address, look for it in the module exception tables. */
4306 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
4308 const struct exception_table_entry
*e
= NULL
;
4312 mod
= __module_address(addr
);
4316 if (!mod
->num_exentries
)
4319 e
= search_extable(mod
->extable
,
4326 * Now, if we found one, we are running inside it now, hence
4327 * we cannot unload the module, hence no refcnt needed.
4333 * is_module_address - is this address inside a module?
4334 * @addr: the address to check.
4336 * See is_module_text_address() if you simply want to see if the address
4337 * is code (not data).
4339 bool is_module_address(unsigned long addr
)
4344 ret
= __module_address(addr
) != NULL
;
4351 * __module_address - get the module which contains an address.
4352 * @addr: the address.
4354 * Must be called with preempt disabled or module mutex held so that
4355 * module doesn't get freed during this.
4357 struct module
*__module_address(unsigned long addr
)
4361 if (addr
< module_addr_min
|| addr
> module_addr_max
)
4364 module_assert_mutex_or_preempt();
4366 mod
= mod_find(addr
);
4368 BUG_ON(!within_module(addr
, mod
));
4369 if (mod
->state
== MODULE_STATE_UNFORMED
)
4374 EXPORT_SYMBOL_GPL(__module_address
);
4377 * is_module_text_address - is this address inside module code?
4378 * @addr: the address to check.
4380 * See is_module_address() if you simply want to see if the address is
4381 * anywhere in a module. See kernel_text_address() for testing if an
4382 * address corresponds to kernel or module code.
4384 bool is_module_text_address(unsigned long addr
)
4389 ret
= __module_text_address(addr
) != NULL
;
4396 * __module_text_address - get the module whose code contains an address.
4397 * @addr: the address.
4399 * Must be called with preempt disabled or module mutex held so that
4400 * module doesn't get freed during this.
4402 struct module
*__module_text_address(unsigned long addr
)
4404 struct module
*mod
= __module_address(addr
);
4406 /* Make sure it's within the text section. */
4407 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4408 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4413 EXPORT_SYMBOL_GPL(__module_text_address
);
4415 /* Don't grab lock, we're oopsing. */
4416 void print_modules(void)
4419 char buf
[MODULE_FLAGS_BUF_SIZE
];
4421 printk(KERN_DEFAULT
"Modules linked in:");
4422 /* Most callers should already have preempt disabled, but make sure */
4424 list_for_each_entry_rcu(mod
, &modules
, list
) {
4425 if (mod
->state
== MODULE_STATE_UNFORMED
)
4427 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4430 if (last_unloaded_module
[0])
4431 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4435 #ifdef CONFIG_MODVERSIONS
4436 /* Generate the signature for all relevant module structures here.
4437 * If these change, we don't want to try to parse the module. */
4438 void module_layout(struct module
*mod
,
4439 struct modversion_info
*ver
,
4440 struct kernel_param
*kp
,
4441 struct kernel_symbol
*ks
,
4442 struct tracepoint
* const *tp
)
4445 EXPORT_SYMBOL(module_layout
);