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 #ifdef CONFIG_MODULES_TREE_LOOKUP
104 * Use a latched RB-tree for __module_address(); this allows us to use
105 * RCU-sched lookups of the address from any context.
107 * This is conditional on PERF_EVENTS || TRACING because those can really hit
108 * __module_address() hard by doing a lot of stack unwinding; potentially from
112 static __always_inline
unsigned long __mod_tree_val(struct latch_tree_node
*n
)
114 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
116 return (unsigned long)layout
->base
;
119 static __always_inline
unsigned long __mod_tree_size(struct latch_tree_node
*n
)
121 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
123 return (unsigned long)layout
->size
;
126 static __always_inline
bool
127 mod_tree_less(struct latch_tree_node
*a
, struct latch_tree_node
*b
)
129 return __mod_tree_val(a
) < __mod_tree_val(b
);
132 static __always_inline
int
133 mod_tree_comp(void *key
, struct latch_tree_node
*n
)
135 unsigned long val
= (unsigned long)key
;
136 unsigned long start
, end
;
138 start
= __mod_tree_val(n
);
142 end
= start
+ __mod_tree_size(n
);
149 static const struct latch_tree_ops mod_tree_ops
= {
150 .less
= mod_tree_less
,
151 .comp
= mod_tree_comp
,
154 static struct mod_tree_root
{
155 struct latch_tree_root root
;
156 unsigned long addr_min
;
157 unsigned long addr_max
;
158 } mod_tree __cacheline_aligned
= {
162 #define module_addr_min mod_tree.addr_min
163 #define module_addr_max mod_tree.addr_max
165 static noinline
void __mod_tree_insert(struct mod_tree_node
*node
)
167 latch_tree_insert(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
170 static void __mod_tree_remove(struct mod_tree_node
*node
)
172 latch_tree_erase(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
176 * These modifications: insert, remove_init and remove; are serialized by the
179 static void mod_tree_insert(struct module
*mod
)
181 mod
->core_layout
.mtn
.mod
= mod
;
182 mod
->init_layout
.mtn
.mod
= mod
;
184 __mod_tree_insert(&mod
->core_layout
.mtn
);
185 if (mod
->init_layout
.size
)
186 __mod_tree_insert(&mod
->init_layout
.mtn
);
189 static void mod_tree_remove_init(struct module
*mod
)
191 if (mod
->init_layout
.size
)
192 __mod_tree_remove(&mod
->init_layout
.mtn
);
195 static void mod_tree_remove(struct module
*mod
)
197 __mod_tree_remove(&mod
->core_layout
.mtn
);
198 mod_tree_remove_init(mod
);
201 static struct module
*mod_find(unsigned long addr
)
203 struct latch_tree_node
*ltn
;
205 ltn
= latch_tree_find((void *)addr
, &mod_tree
.root
, &mod_tree_ops
);
209 return container_of(ltn
, struct mod_tree_node
, node
)->mod
;
212 #else /* MODULES_TREE_LOOKUP */
214 static unsigned long module_addr_min
= -1UL, module_addr_max
= 0;
216 static void mod_tree_insert(struct module
*mod
) { }
217 static void mod_tree_remove_init(struct module
*mod
) { }
218 static void mod_tree_remove(struct module
*mod
) { }
220 static struct module
*mod_find(unsigned long addr
)
224 list_for_each_entry_rcu(mod
, &modules
, list
) {
225 if (within_module(addr
, mod
))
232 #endif /* MODULES_TREE_LOOKUP */
235 * Bounds of module text, for speeding up __module_address.
236 * Protected by module_mutex.
238 static void __mod_update_bounds(void *base
, unsigned int size
)
240 unsigned long min
= (unsigned long)base
;
241 unsigned long max
= min
+ size
;
243 if (min
< module_addr_min
)
244 module_addr_min
= min
;
245 if (max
> module_addr_max
)
246 module_addr_max
= max
;
249 static void mod_update_bounds(struct module
*mod
)
251 __mod_update_bounds(mod
->core_layout
.base
, mod
->core_layout
.size
);
252 if (mod
->init_layout
.size
)
253 __mod_update_bounds(mod
->init_layout
.base
, mod
->init_layout
.size
);
256 #ifdef CONFIG_KGDB_KDB
257 struct list_head
*kdb_modules
= &modules
; /* kdb needs the list of modules */
258 #endif /* CONFIG_KGDB_KDB */
260 static void module_assert_mutex(void)
262 lockdep_assert_held(&module_mutex
);
265 static void module_assert_mutex_or_preempt(void)
267 #ifdef CONFIG_LOCKDEP
268 if (unlikely(!debug_locks
))
271 WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
272 !lockdep_is_held(&module_mutex
));
276 static bool sig_enforce
= IS_ENABLED(CONFIG_MODULE_SIG_FORCE
);
277 #ifndef CONFIG_MODULE_SIG_FORCE
278 module_param(sig_enforce
, bool_enable_only
, 0644);
279 #endif /* !CONFIG_MODULE_SIG_FORCE */
281 /* Block module loading/unloading? */
282 int modules_disabled
= 0;
283 core_param(nomodule
, modules_disabled
, bint
, 0);
285 /* Waiting for a module to finish initializing? */
286 static DECLARE_WAIT_QUEUE_HEAD(module_wq
);
288 static BLOCKING_NOTIFIER_HEAD(module_notify_list
);
290 int register_module_notifier(struct notifier_block
*nb
)
292 return blocking_notifier_chain_register(&module_notify_list
, nb
);
294 EXPORT_SYMBOL(register_module_notifier
);
296 int unregister_module_notifier(struct notifier_block
*nb
)
298 return blocking_notifier_chain_unregister(&module_notify_list
, nb
);
300 EXPORT_SYMBOL(unregister_module_notifier
);
307 char *secstrings
, *strtab
;
308 unsigned long symoffs
, stroffs
;
309 struct _ddebug
*debug
;
310 unsigned int num_debug
;
312 #ifdef CONFIG_KALLSYMS
313 unsigned long mod_kallsyms_init_off
;
316 unsigned int sym
, str
, mod
, vers
, info
, pcpu
;
321 * We require a truly strong try_module_get(): 0 means success.
322 * Otherwise an error is returned due to ongoing or failed
323 * initialization etc.
325 static inline int strong_try_module_get(struct module
*mod
)
327 BUG_ON(mod
&& mod
->state
== MODULE_STATE_UNFORMED
);
328 if (mod
&& mod
->state
== MODULE_STATE_COMING
)
330 if (try_module_get(mod
))
336 static inline void add_taint_module(struct module
*mod
, unsigned flag
,
337 enum lockdep_ok lockdep_ok
)
339 add_taint(flag
, lockdep_ok
);
340 set_bit(flag
, &mod
->taints
);
344 * A thread that wants to hold a reference to a module only while it
345 * is running can call this to safely exit. nfsd and lockd use this.
347 void __noreturn
__module_put_and_exit(struct module
*mod
, long code
)
352 EXPORT_SYMBOL(__module_put_and_exit
);
354 /* Find a module section: 0 means not found. */
355 static unsigned int find_sec(const struct load_info
*info
, const char *name
)
359 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
360 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
361 /* Alloc bit cleared means "ignore it." */
362 if ((shdr
->sh_flags
& SHF_ALLOC
)
363 && strcmp(info
->secstrings
+ shdr
->sh_name
, name
) == 0)
369 /* Find a module section, or NULL. */
370 static void *section_addr(const struct load_info
*info
, const char *name
)
372 /* Section 0 has sh_addr 0. */
373 return (void *)info
->sechdrs
[find_sec(info
, name
)].sh_addr
;
376 /* Find a module section, or NULL. Fill in number of "objects" in section. */
377 static void *section_objs(const struct load_info
*info
,
382 unsigned int sec
= find_sec(info
, name
);
384 /* Section 0 has sh_addr 0 and sh_size 0. */
385 *num
= info
->sechdrs
[sec
].sh_size
/ object_size
;
386 return (void *)info
->sechdrs
[sec
].sh_addr
;
389 /* Provided by the linker */
390 extern const struct kernel_symbol __start___ksymtab
[];
391 extern const struct kernel_symbol __stop___ksymtab
[];
392 extern const struct kernel_symbol __start___ksymtab_gpl
[];
393 extern const struct kernel_symbol __stop___ksymtab_gpl
[];
394 extern const struct kernel_symbol __start___ksymtab_gpl_future
[];
395 extern const struct kernel_symbol __stop___ksymtab_gpl_future
[];
396 extern const s32 __start___kcrctab
[];
397 extern const s32 __start___kcrctab_gpl
[];
398 extern const s32 __start___kcrctab_gpl_future
[];
399 #ifdef CONFIG_UNUSED_SYMBOLS
400 extern const struct kernel_symbol __start___ksymtab_unused
[];
401 extern const struct kernel_symbol __stop___ksymtab_unused
[];
402 extern const struct kernel_symbol __start___ksymtab_unused_gpl
[];
403 extern const struct kernel_symbol __stop___ksymtab_unused_gpl
[];
404 extern const s32 __start___kcrctab_unused
[];
405 extern const s32 __start___kcrctab_unused_gpl
[];
408 #ifndef CONFIG_MODVERSIONS
409 #define symversion(base, idx) NULL
411 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
414 static bool each_symbol_in_section(const struct symsearch
*arr
,
415 unsigned int arrsize
,
416 struct module
*owner
,
417 bool (*fn
)(const struct symsearch
*syms
,
418 struct module
*owner
,
424 for (j
= 0; j
< arrsize
; j
++) {
425 if (fn(&arr
[j
], owner
, data
))
432 /* Returns true as soon as fn returns true, otherwise false. */
433 bool each_symbol_section(bool (*fn
)(const struct symsearch
*arr
,
434 struct module
*owner
,
439 static const struct symsearch arr
[] = {
440 { __start___ksymtab
, __stop___ksymtab
, __start___kcrctab
,
441 NOT_GPL_ONLY
, false },
442 { __start___ksymtab_gpl
, __stop___ksymtab_gpl
,
443 __start___kcrctab_gpl
,
445 { __start___ksymtab_gpl_future
, __stop___ksymtab_gpl_future
,
446 __start___kcrctab_gpl_future
,
447 WILL_BE_GPL_ONLY
, false },
448 #ifdef CONFIG_UNUSED_SYMBOLS
449 { __start___ksymtab_unused
, __stop___ksymtab_unused
,
450 __start___kcrctab_unused
,
451 NOT_GPL_ONLY
, true },
452 { __start___ksymtab_unused_gpl
, __stop___ksymtab_unused_gpl
,
453 __start___kcrctab_unused_gpl
,
458 module_assert_mutex_or_preempt();
460 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), NULL
, fn
, data
))
463 list_for_each_entry_rcu(mod
, &modules
, list
) {
464 struct symsearch arr
[] = {
465 { mod
->syms
, mod
->syms
+ mod
->num_syms
, mod
->crcs
,
466 NOT_GPL_ONLY
, false },
467 { mod
->gpl_syms
, mod
->gpl_syms
+ mod
->num_gpl_syms
,
470 { mod
->gpl_future_syms
,
471 mod
->gpl_future_syms
+ mod
->num_gpl_future_syms
,
472 mod
->gpl_future_crcs
,
473 WILL_BE_GPL_ONLY
, false },
474 #ifdef CONFIG_UNUSED_SYMBOLS
476 mod
->unused_syms
+ mod
->num_unused_syms
,
478 NOT_GPL_ONLY
, true },
479 { mod
->unused_gpl_syms
,
480 mod
->unused_gpl_syms
+ mod
->num_unused_gpl_syms
,
481 mod
->unused_gpl_crcs
,
486 if (mod
->state
== MODULE_STATE_UNFORMED
)
489 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), mod
, fn
, data
))
494 EXPORT_SYMBOL_GPL(each_symbol_section
);
496 struct find_symbol_arg
{
503 struct module
*owner
;
505 const struct kernel_symbol
*sym
;
508 static bool check_symbol(const struct symsearch
*syms
,
509 struct module
*owner
,
510 unsigned int symnum
, void *data
)
512 struct find_symbol_arg
*fsa
= data
;
515 if (syms
->licence
== GPL_ONLY
)
517 if (syms
->licence
== WILL_BE_GPL_ONLY
&& fsa
->warn
) {
518 pr_warn("Symbol %s is being used by a non-GPL module, "
519 "which will not be allowed in the future\n",
524 #ifdef CONFIG_UNUSED_SYMBOLS
525 if (syms
->unused
&& fsa
->warn
) {
526 pr_warn("Symbol %s is marked as UNUSED, however this module is "
527 "using it.\n", fsa
->name
);
528 pr_warn("This symbol will go away in the future.\n");
529 pr_warn("Please evaluate if this is the right api to use and "
530 "if it really is, submit a report to the linux kernel "
531 "mailing list together with submitting your code for "
537 fsa
->crc
= symversion(syms
->crcs
, symnum
);
538 fsa
->sym
= &syms
->start
[symnum
];
542 static int cmp_name(const void *va
, const void *vb
)
545 const struct kernel_symbol
*b
;
547 return strcmp(a
, b
->name
);
550 static bool find_symbol_in_section(const struct symsearch
*syms
,
551 struct module
*owner
,
554 struct find_symbol_arg
*fsa
= data
;
555 struct kernel_symbol
*sym
;
557 sym
= bsearch(fsa
->name
, syms
->start
, syms
->stop
- syms
->start
,
558 sizeof(struct kernel_symbol
), cmp_name
);
560 if (sym
!= NULL
&& check_symbol(syms
, owner
, sym
- syms
->start
, data
))
566 /* Find a symbol and return it, along with, (optional) crc and
567 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
568 const struct kernel_symbol
*find_symbol(const char *name
,
569 struct module
**owner
,
574 struct find_symbol_arg fsa
;
580 if (each_symbol_section(find_symbol_in_section
, &fsa
)) {
588 pr_debug("Failed to find symbol %s\n", name
);
591 EXPORT_SYMBOL_GPL(find_symbol
);
594 * Search for module by name: must hold module_mutex (or preempt disabled
595 * for read-only access).
597 static struct module
*find_module_all(const char *name
, size_t len
,
602 module_assert_mutex_or_preempt();
604 list_for_each_entry_rcu(mod
, &modules
, list
) {
605 if (!even_unformed
&& mod
->state
== MODULE_STATE_UNFORMED
)
607 if (strlen(mod
->name
) == len
&& !memcmp(mod
->name
, name
, len
))
613 struct module
*find_module(const char *name
)
615 module_assert_mutex();
616 return find_module_all(name
, strlen(name
), false);
618 EXPORT_SYMBOL_GPL(find_module
);
622 static inline void __percpu
*mod_percpu(struct module
*mod
)
627 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
629 Elf_Shdr
*pcpusec
= &info
->sechdrs
[info
->index
.pcpu
];
630 unsigned long align
= pcpusec
->sh_addralign
;
632 if (!pcpusec
->sh_size
)
635 if (align
> PAGE_SIZE
) {
636 pr_warn("%s: per-cpu alignment %li > %li\n",
637 mod
->name
, align
, PAGE_SIZE
);
641 mod
->percpu
= __alloc_reserved_percpu(pcpusec
->sh_size
, align
);
643 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
644 mod
->name
, (unsigned long)pcpusec
->sh_size
);
647 mod
->percpu_size
= pcpusec
->sh_size
;
651 static void percpu_modfree(struct module
*mod
)
653 free_percpu(mod
->percpu
);
656 static unsigned int find_pcpusec(struct load_info
*info
)
658 return find_sec(info
, ".data..percpu");
661 static void percpu_modcopy(struct module
*mod
,
662 const void *from
, unsigned long size
)
666 for_each_possible_cpu(cpu
)
667 memcpy(per_cpu_ptr(mod
->percpu
, cpu
), from
, size
);
670 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
677 list_for_each_entry_rcu(mod
, &modules
, list
) {
678 if (mod
->state
== MODULE_STATE_UNFORMED
)
680 if (!mod
->percpu_size
)
682 for_each_possible_cpu(cpu
) {
683 void *start
= per_cpu_ptr(mod
->percpu
, cpu
);
684 void *va
= (void *)addr
;
686 if (va
>= start
&& va
< start
+ mod
->percpu_size
) {
688 *can_addr
= (unsigned long) (va
- start
);
689 *can_addr
+= (unsigned long)
690 per_cpu_ptr(mod
->percpu
,
704 * is_module_percpu_address - test whether address is from module static percpu
705 * @addr: address to test
707 * Test whether @addr belongs to module static percpu area.
710 * %true if @addr is from module static percpu area
712 bool is_module_percpu_address(unsigned long addr
)
714 return __is_module_percpu_address(addr
, NULL
);
717 #else /* ... !CONFIG_SMP */
719 static inline void __percpu
*mod_percpu(struct module
*mod
)
723 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
725 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
726 if (info
->sechdrs
[info
->index
.pcpu
].sh_size
!= 0)
730 static inline void percpu_modfree(struct module
*mod
)
733 static unsigned int find_pcpusec(struct load_info
*info
)
737 static inline void percpu_modcopy(struct module
*mod
,
738 const void *from
, unsigned long size
)
740 /* pcpusec should be 0, and size of that section should be 0. */
743 bool is_module_percpu_address(unsigned long addr
)
748 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
753 #endif /* CONFIG_SMP */
755 #define MODINFO_ATTR(field) \
756 static void setup_modinfo_##field(struct module *mod, const char *s) \
758 mod->field = kstrdup(s, GFP_KERNEL); \
760 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
761 struct module_kobject *mk, char *buffer) \
763 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
765 static int modinfo_##field##_exists(struct module *mod) \
767 return mod->field != NULL; \
769 static void free_modinfo_##field(struct module *mod) \
774 static struct module_attribute modinfo_##field = { \
775 .attr = { .name = __stringify(field), .mode = 0444 }, \
776 .show = show_modinfo_##field, \
777 .setup = setup_modinfo_##field, \
778 .test = modinfo_##field##_exists, \
779 .free = free_modinfo_##field, \
782 MODINFO_ATTR(version
);
783 MODINFO_ATTR(srcversion
);
785 static char last_unloaded_module
[MODULE_NAME_LEN
+1];
787 #ifdef CONFIG_MODULE_UNLOAD
789 EXPORT_TRACEPOINT_SYMBOL(module_get
);
791 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
792 #define MODULE_REF_BASE 1
794 /* Init the unload section of the module. */
795 static int module_unload_init(struct module
*mod
)
798 * Initialize reference counter to MODULE_REF_BASE.
799 * refcnt == 0 means module is going.
801 atomic_set(&mod
->refcnt
, MODULE_REF_BASE
);
803 INIT_LIST_HEAD(&mod
->source_list
);
804 INIT_LIST_HEAD(&mod
->target_list
);
806 /* Hold reference count during initialization. */
807 atomic_inc(&mod
->refcnt
);
812 /* Does a already use b? */
813 static int already_uses(struct module
*a
, struct module
*b
)
815 struct module_use
*use
;
817 list_for_each_entry(use
, &b
->source_list
, source_list
) {
818 if (use
->source
== a
) {
819 pr_debug("%s uses %s!\n", a
->name
, b
->name
);
823 pr_debug("%s does not use %s!\n", a
->name
, b
->name
);
829 * - we add 'a' as a "source", 'b' as a "target" of module use
830 * - the module_use is added to the list of 'b' sources (so
831 * 'b' can walk the list to see who sourced them), and of 'a'
832 * targets (so 'a' can see what modules it targets).
834 static int add_module_usage(struct module
*a
, struct module
*b
)
836 struct module_use
*use
;
838 pr_debug("Allocating new usage for %s.\n", a
->name
);
839 use
= kmalloc(sizeof(*use
), GFP_ATOMIC
);
841 pr_warn("%s: out of memory loading\n", a
->name
);
847 list_add(&use
->source_list
, &b
->source_list
);
848 list_add(&use
->target_list
, &a
->target_list
);
852 /* Module a uses b: caller needs module_mutex() */
853 int ref_module(struct module
*a
, struct module
*b
)
857 if (b
== NULL
|| already_uses(a
, b
))
860 /* If module isn't available, we fail. */
861 err
= strong_try_module_get(b
);
865 err
= add_module_usage(a
, b
);
872 EXPORT_SYMBOL_GPL(ref_module
);
874 /* Clear the unload stuff of the module. */
875 static void module_unload_free(struct module
*mod
)
877 struct module_use
*use
, *tmp
;
879 mutex_lock(&module_mutex
);
880 list_for_each_entry_safe(use
, tmp
, &mod
->target_list
, target_list
) {
881 struct module
*i
= use
->target
;
882 pr_debug("%s unusing %s\n", mod
->name
, i
->name
);
884 list_del(&use
->source_list
);
885 list_del(&use
->target_list
);
888 mutex_unlock(&module_mutex
);
891 #ifdef CONFIG_MODULE_FORCE_UNLOAD
892 static inline int try_force_unload(unsigned int flags
)
894 int ret
= (flags
& O_TRUNC
);
896 add_taint(TAINT_FORCED_RMMOD
, LOCKDEP_NOW_UNRELIABLE
);
900 static inline int try_force_unload(unsigned int flags
)
904 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
906 /* Try to release refcount of module, 0 means success. */
907 static int try_release_module_ref(struct module
*mod
)
911 /* Try to decrement refcnt which we set at loading */
912 ret
= atomic_sub_return(MODULE_REF_BASE
, &mod
->refcnt
);
915 /* Someone can put this right now, recover with checking */
916 ret
= atomic_add_unless(&mod
->refcnt
, MODULE_REF_BASE
, 0);
921 static int try_stop_module(struct module
*mod
, int flags
, int *forced
)
923 /* If it's not unused, quit unless we're forcing. */
924 if (try_release_module_ref(mod
) != 0) {
925 *forced
= try_force_unload(flags
);
930 /* Mark it as dying. */
931 mod
->state
= MODULE_STATE_GOING
;
937 * module_refcount - return the refcount or -1 if unloading
939 * @mod: the module we're checking
942 * -1 if the module is in the process of unloading
943 * otherwise the number of references in the kernel to the module
945 int module_refcount(struct module
*mod
)
947 return atomic_read(&mod
->refcnt
) - MODULE_REF_BASE
;
949 EXPORT_SYMBOL(module_refcount
);
951 /* This exists whether we can unload or not */
952 static void free_module(struct module
*mod
);
954 SYSCALL_DEFINE2(delete_module
, const char __user
*, name_user
,
958 char name
[MODULE_NAME_LEN
];
961 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
964 if (strncpy_from_user(name
, name_user
, MODULE_NAME_LEN
-1) < 0)
966 name
[MODULE_NAME_LEN
-1] = '\0';
968 audit_log_kern_module(name
);
970 if (mutex_lock_interruptible(&module_mutex
) != 0)
973 mod
= find_module(name
);
979 if (!list_empty(&mod
->source_list
)) {
980 /* Other modules depend on us: get rid of them first. */
985 /* Doing init or already dying? */
986 if (mod
->state
!= MODULE_STATE_LIVE
) {
987 /* FIXME: if (force), slam module count damn the torpedoes */
988 pr_debug("%s already dying\n", mod
->name
);
993 /* If it has an init func, it must have an exit func to unload */
994 if (mod
->init
&& !mod
->exit
) {
995 forced
= try_force_unload(flags
);
997 /* This module can't be removed */
1003 /* Stop the machine so refcounts can't move and disable module. */
1004 ret
= try_stop_module(mod
, flags
, &forced
);
1008 mutex_unlock(&module_mutex
);
1009 /* Final destruction now no one is using it. */
1010 if (mod
->exit
!= NULL
)
1012 blocking_notifier_call_chain(&module_notify_list
,
1013 MODULE_STATE_GOING
, mod
);
1014 klp_module_going(mod
);
1015 ftrace_release_mod(mod
);
1017 async_synchronize_full();
1019 /* Store the name of the last unloaded module for diagnostic purposes */
1020 strlcpy(last_unloaded_module
, mod
->name
, sizeof(last_unloaded_module
));
1025 mutex_unlock(&module_mutex
);
1029 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1031 struct module_use
*use
;
1032 int printed_something
= 0;
1034 seq_printf(m
, " %i ", module_refcount(mod
));
1037 * Always include a trailing , so userspace can differentiate
1038 * between this and the old multi-field proc format.
1040 list_for_each_entry(use
, &mod
->source_list
, source_list
) {
1041 printed_something
= 1;
1042 seq_printf(m
, "%s,", use
->source
->name
);
1045 if (mod
->init
!= NULL
&& mod
->exit
== NULL
) {
1046 printed_something
= 1;
1047 seq_puts(m
, "[permanent],");
1050 if (!printed_something
)
1054 void __symbol_put(const char *symbol
)
1056 struct module
*owner
;
1059 if (!find_symbol(symbol
, &owner
, NULL
, true, false))
1064 EXPORT_SYMBOL(__symbol_put
);
1066 /* Note this assumes addr is a function, which it currently always is. */
1067 void symbol_put_addr(void *addr
)
1069 struct module
*modaddr
;
1070 unsigned long a
= (unsigned long)dereference_function_descriptor(addr
);
1072 if (core_kernel_text(a
))
1076 * Even though we hold a reference on the module; we still need to
1077 * disable preemption in order to safely traverse the data structure.
1080 modaddr
= __module_text_address(a
);
1082 module_put(modaddr
);
1085 EXPORT_SYMBOL_GPL(symbol_put_addr
);
1087 static ssize_t
show_refcnt(struct module_attribute
*mattr
,
1088 struct module_kobject
*mk
, char *buffer
)
1090 return sprintf(buffer
, "%i\n", module_refcount(mk
->mod
));
1093 static struct module_attribute modinfo_refcnt
=
1094 __ATTR(refcnt
, 0444, show_refcnt
, NULL
);
1096 void __module_get(struct module
*module
)
1100 atomic_inc(&module
->refcnt
);
1101 trace_module_get(module
, _RET_IP_
);
1105 EXPORT_SYMBOL(__module_get
);
1107 bool try_module_get(struct module
*module
)
1113 /* Note: here, we can fail to get a reference */
1114 if (likely(module_is_live(module
) &&
1115 atomic_inc_not_zero(&module
->refcnt
) != 0))
1116 trace_module_get(module
, _RET_IP_
);
1124 EXPORT_SYMBOL(try_module_get
);
1126 void module_put(struct module
*module
)
1132 ret
= atomic_dec_if_positive(&module
->refcnt
);
1133 WARN_ON(ret
< 0); /* Failed to put refcount */
1134 trace_module_put(module
, _RET_IP_
);
1138 EXPORT_SYMBOL(module_put
);
1140 #else /* !CONFIG_MODULE_UNLOAD */
1141 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1143 /* We don't know the usage count, or what modules are using. */
1144 seq_puts(m
, " - -");
1147 static inline void module_unload_free(struct module
*mod
)
1151 int ref_module(struct module
*a
, struct module
*b
)
1153 return strong_try_module_get(b
);
1155 EXPORT_SYMBOL_GPL(ref_module
);
1157 static inline int module_unload_init(struct module
*mod
)
1161 #endif /* CONFIG_MODULE_UNLOAD */
1163 static size_t module_flags_taint(struct module
*mod
, char *buf
)
1168 for (i
= 0; i
< TAINT_FLAGS_COUNT
; i
++) {
1169 if (taint_flags
[i
].module
&& test_bit(i
, &mod
->taints
))
1170 buf
[l
++] = taint_flags
[i
].c_true
;
1176 static ssize_t
show_initstate(struct module_attribute
*mattr
,
1177 struct module_kobject
*mk
, char *buffer
)
1179 const char *state
= "unknown";
1181 switch (mk
->mod
->state
) {
1182 case MODULE_STATE_LIVE
:
1185 case MODULE_STATE_COMING
:
1188 case MODULE_STATE_GOING
:
1194 return sprintf(buffer
, "%s\n", state
);
1197 static struct module_attribute modinfo_initstate
=
1198 __ATTR(initstate
, 0444, show_initstate
, NULL
);
1200 static ssize_t
store_uevent(struct module_attribute
*mattr
,
1201 struct module_kobject
*mk
,
1202 const char *buffer
, size_t count
)
1204 kobject_synth_uevent(&mk
->kobj
, buffer
, count
);
1208 struct module_attribute module_uevent
=
1209 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1211 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1212 struct module_kobject
*mk
, char *buffer
)
1214 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1217 static struct module_attribute modinfo_coresize
=
1218 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1220 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1221 struct module_kobject
*mk
, char *buffer
)
1223 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1226 static struct module_attribute modinfo_initsize
=
1227 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1229 static ssize_t
show_taint(struct module_attribute
*mattr
,
1230 struct module_kobject
*mk
, char *buffer
)
1234 l
= module_flags_taint(mk
->mod
, buffer
);
1239 static struct module_attribute modinfo_taint
=
1240 __ATTR(taint
, 0444, show_taint
, NULL
);
1242 static struct module_attribute
*modinfo_attrs
[] = {
1245 &modinfo_srcversion
,
1250 #ifdef CONFIG_MODULE_UNLOAD
1256 static const char vermagic
[] = VERMAGIC_STRING
;
1258 static int try_to_force_load(struct module
*mod
, const char *reason
)
1260 #ifdef CONFIG_MODULE_FORCE_LOAD
1261 if (!test_taint(TAINT_FORCED_MODULE
))
1262 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1263 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1270 #ifdef CONFIG_MODVERSIONS
1272 static u32
resolve_rel_crc(const s32
*crc
)
1274 return *(u32
*)((void *)crc
+ *crc
);
1277 static int check_version(const struct load_info
*info
,
1278 const char *symname
,
1282 Elf_Shdr
*sechdrs
= info
->sechdrs
;
1283 unsigned int versindex
= info
->index
.vers
;
1284 unsigned int i
, num_versions
;
1285 struct modversion_info
*versions
;
1287 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1291 /* No versions at all? modprobe --force does this. */
1293 return try_to_force_load(mod
, symname
) == 0;
1295 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1296 num_versions
= sechdrs
[versindex
].sh_size
1297 / sizeof(struct modversion_info
);
1299 for (i
= 0; i
< num_versions
; i
++) {
1302 if (strcmp(versions
[i
].name
, symname
) != 0)
1305 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS
))
1306 crcval
= resolve_rel_crc(crc
);
1309 if (versions
[i
].crc
== crcval
)
1311 pr_debug("Found checksum %X vs module %lX\n",
1312 crcval
, versions
[i
].crc
);
1316 /* Broken toolchain. Warn once, then let it go.. */
1317 pr_warn_once("%s: no symbol version for %s\n", info
->name
, symname
);
1321 pr_warn("%s: disagrees about version of symbol %s\n",
1322 info
->name
, symname
);
1326 static inline int check_modstruct_version(const struct load_info
*info
,
1332 * Since this should be found in kernel (which can't be removed), no
1333 * locking is necessary -- use preempt_disable() to placate lockdep.
1336 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout
), NULL
,
1337 &crc
, true, false)) {
1342 return check_version(info
, VMLINUX_SYMBOL_STR(module_layout
),
1346 /* First part is kernel version, which we ignore if module has crcs. */
1347 static inline int same_magic(const char *amagic
, const char *bmagic
,
1351 amagic
+= strcspn(amagic
, " ");
1352 bmagic
+= strcspn(bmagic
, " ");
1354 return strcmp(amagic
, bmagic
) == 0;
1357 static inline int check_version(const struct load_info
*info
,
1358 const char *symname
,
1365 static inline int check_modstruct_version(const struct load_info
*info
,
1371 static inline int same_magic(const char *amagic
, const char *bmagic
,
1374 return strcmp(amagic
, bmagic
) == 0;
1376 #endif /* CONFIG_MODVERSIONS */
1378 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1379 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1380 const struct load_info
*info
,
1384 struct module
*owner
;
1385 const struct kernel_symbol
*sym
;
1390 * The module_mutex should not be a heavily contended lock;
1391 * if we get the occasional sleep here, we'll go an extra iteration
1392 * in the wait_event_interruptible(), which is harmless.
1394 sched_annotate_sleep();
1395 mutex_lock(&module_mutex
);
1396 sym
= find_symbol(name
, &owner
, &crc
,
1397 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1401 if (!check_version(info
, name
, mod
, crc
)) {
1402 sym
= ERR_PTR(-EINVAL
);
1406 err
= ref_module(mod
, owner
);
1413 /* We must make copy under the lock if we failed to get ref. */
1414 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1416 mutex_unlock(&module_mutex
);
1420 static const struct kernel_symbol
*
1421 resolve_symbol_wait(struct module
*mod
,
1422 const struct load_info
*info
,
1425 const struct kernel_symbol
*ksym
;
1426 char owner
[MODULE_NAME_LEN
];
1428 if (wait_event_interruptible_timeout(module_wq
,
1429 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1430 || PTR_ERR(ksym
) != -EBUSY
,
1432 pr_warn("%s: gave up waiting for init of module %s.\n",
1439 * /sys/module/foo/sections stuff
1440 * J. Corbet <corbet@lwn.net>
1444 #ifdef CONFIG_KALLSYMS
1445 static inline bool sect_empty(const Elf_Shdr
*sect
)
1447 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1450 struct module_sect_attr
{
1451 struct module_attribute mattr
;
1453 unsigned long address
;
1456 struct module_sect_attrs
{
1457 struct attribute_group grp
;
1458 unsigned int nsections
;
1459 struct module_sect_attr attrs
[0];
1462 static ssize_t
module_sect_show(struct module_attribute
*mattr
,
1463 struct module_kobject
*mk
, char *buf
)
1465 struct module_sect_attr
*sattr
=
1466 container_of(mattr
, struct module_sect_attr
, mattr
);
1467 return sprintf(buf
, "0x%pK\n", (void *)sattr
->address
);
1470 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1472 unsigned int section
;
1474 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1475 kfree(sect_attrs
->attrs
[section
].name
);
1479 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1481 unsigned int nloaded
= 0, i
, size
[2];
1482 struct module_sect_attrs
*sect_attrs
;
1483 struct module_sect_attr
*sattr
;
1484 struct attribute
**gattr
;
1486 /* Count loaded sections and allocate structures */
1487 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1488 if (!sect_empty(&info
->sechdrs
[i
]))
1490 size
[0] = ALIGN(sizeof(*sect_attrs
)
1491 + nloaded
* sizeof(sect_attrs
->attrs
[0]),
1492 sizeof(sect_attrs
->grp
.attrs
[0]));
1493 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.attrs
[0]);
1494 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1495 if (sect_attrs
== NULL
)
1498 /* Setup section attributes. */
1499 sect_attrs
->grp
.name
= "sections";
1500 sect_attrs
->grp
.attrs
= (void *)sect_attrs
+ size
[0];
1502 sect_attrs
->nsections
= 0;
1503 sattr
= §_attrs
->attrs
[0];
1504 gattr
= §_attrs
->grp
.attrs
[0];
1505 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1506 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1507 if (sect_empty(sec
))
1509 sattr
->address
= sec
->sh_addr
;
1510 sattr
->name
= kstrdup(info
->secstrings
+ sec
->sh_name
,
1512 if (sattr
->name
== NULL
)
1514 sect_attrs
->nsections
++;
1515 sysfs_attr_init(&sattr
->mattr
.attr
);
1516 sattr
->mattr
.show
= module_sect_show
;
1517 sattr
->mattr
.store
= NULL
;
1518 sattr
->mattr
.attr
.name
= sattr
->name
;
1519 sattr
->mattr
.attr
.mode
= S_IRUGO
;
1520 *(gattr
++) = &(sattr
++)->mattr
.attr
;
1524 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1527 mod
->sect_attrs
= sect_attrs
;
1530 free_sect_attrs(sect_attrs
);
1533 static void remove_sect_attrs(struct module
*mod
)
1535 if (mod
->sect_attrs
) {
1536 sysfs_remove_group(&mod
->mkobj
.kobj
,
1537 &mod
->sect_attrs
->grp
);
1538 /* We are positive that no one is using any sect attrs
1539 * at this point. Deallocate immediately. */
1540 free_sect_attrs(mod
->sect_attrs
);
1541 mod
->sect_attrs
= NULL
;
1546 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1549 struct module_notes_attrs
{
1550 struct kobject
*dir
;
1552 struct bin_attribute attrs
[0];
1555 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1556 struct bin_attribute
*bin_attr
,
1557 char *buf
, loff_t pos
, size_t count
)
1560 * The caller checked the pos and count against our size.
1562 memcpy(buf
, bin_attr
->private + pos
, count
);
1566 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1569 if (notes_attrs
->dir
) {
1571 sysfs_remove_bin_file(notes_attrs
->dir
,
1572 ¬es_attrs
->attrs
[i
]);
1573 kobject_put(notes_attrs
->dir
);
1578 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1580 unsigned int notes
, loaded
, i
;
1581 struct module_notes_attrs
*notes_attrs
;
1582 struct bin_attribute
*nattr
;
1584 /* failed to create section attributes, so can't create notes */
1585 if (!mod
->sect_attrs
)
1588 /* Count notes sections and allocate structures. */
1590 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1591 if (!sect_empty(&info
->sechdrs
[i
]) &&
1592 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1598 notes_attrs
= kzalloc(sizeof(*notes_attrs
)
1599 + notes
* sizeof(notes_attrs
->attrs
[0]),
1601 if (notes_attrs
== NULL
)
1604 notes_attrs
->notes
= notes
;
1605 nattr
= ¬es_attrs
->attrs
[0];
1606 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1607 if (sect_empty(&info
->sechdrs
[i
]))
1609 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1610 sysfs_bin_attr_init(nattr
);
1611 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].name
;
1612 nattr
->attr
.mode
= S_IRUGO
;
1613 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1614 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1615 nattr
->read
= module_notes_read
;
1621 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1622 if (!notes_attrs
->dir
)
1625 for (i
= 0; i
< notes
; ++i
)
1626 if (sysfs_create_bin_file(notes_attrs
->dir
,
1627 ¬es_attrs
->attrs
[i
]))
1630 mod
->notes_attrs
= notes_attrs
;
1634 free_notes_attrs(notes_attrs
, i
);
1637 static void remove_notes_attrs(struct module
*mod
)
1639 if (mod
->notes_attrs
)
1640 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1645 static inline void add_sect_attrs(struct module
*mod
,
1646 const struct load_info
*info
)
1650 static inline void remove_sect_attrs(struct module
*mod
)
1654 static inline void add_notes_attrs(struct module
*mod
,
1655 const struct load_info
*info
)
1659 static inline void remove_notes_attrs(struct module
*mod
)
1662 #endif /* CONFIG_KALLSYMS */
1664 static void del_usage_links(struct module
*mod
)
1666 #ifdef CONFIG_MODULE_UNLOAD
1667 struct module_use
*use
;
1669 mutex_lock(&module_mutex
);
1670 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1671 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1672 mutex_unlock(&module_mutex
);
1676 static int add_usage_links(struct module
*mod
)
1679 #ifdef CONFIG_MODULE_UNLOAD
1680 struct module_use
*use
;
1682 mutex_lock(&module_mutex
);
1683 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1684 ret
= sysfs_create_link(use
->target
->holders_dir
,
1685 &mod
->mkobj
.kobj
, mod
->name
);
1689 mutex_unlock(&module_mutex
);
1691 del_usage_links(mod
);
1696 static int module_add_modinfo_attrs(struct module
*mod
)
1698 struct module_attribute
*attr
;
1699 struct module_attribute
*temp_attr
;
1703 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1704 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1706 if (!mod
->modinfo_attrs
)
1709 temp_attr
= mod
->modinfo_attrs
;
1710 for (i
= 0; (attr
= modinfo_attrs
[i
]) && !error
; i
++) {
1711 if (!attr
->test
|| attr
->test(mod
)) {
1712 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1713 sysfs_attr_init(&temp_attr
->attr
);
1714 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1722 static void module_remove_modinfo_attrs(struct module
*mod
)
1724 struct module_attribute
*attr
;
1727 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1728 /* pick a field to test for end of list */
1729 if (!attr
->attr
.name
)
1731 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1735 kfree(mod
->modinfo_attrs
);
1738 static void mod_kobject_put(struct module
*mod
)
1740 DECLARE_COMPLETION_ONSTACK(c
);
1741 mod
->mkobj
.kobj_completion
= &c
;
1742 kobject_put(&mod
->mkobj
.kobj
);
1743 wait_for_completion(&c
);
1746 static int mod_sysfs_init(struct module
*mod
)
1749 struct kobject
*kobj
;
1751 if (!module_sysfs_initialized
) {
1752 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1757 kobj
= kset_find_obj(module_kset
, mod
->name
);
1759 pr_err("%s: module is already loaded\n", mod
->name
);
1765 mod
->mkobj
.mod
= mod
;
1767 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1768 mod
->mkobj
.kobj
.kset
= module_kset
;
1769 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1772 mod_kobject_put(mod
);
1774 /* delay uevent until full sysfs population */
1779 static int mod_sysfs_setup(struct module
*mod
,
1780 const struct load_info
*info
,
1781 struct kernel_param
*kparam
,
1782 unsigned int num_params
)
1786 err
= mod_sysfs_init(mod
);
1790 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1791 if (!mod
->holders_dir
) {
1796 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1798 goto out_unreg_holders
;
1800 err
= module_add_modinfo_attrs(mod
);
1802 goto out_unreg_param
;
1804 err
= add_usage_links(mod
);
1806 goto out_unreg_modinfo_attrs
;
1808 add_sect_attrs(mod
, info
);
1809 add_notes_attrs(mod
, info
);
1811 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1814 out_unreg_modinfo_attrs
:
1815 module_remove_modinfo_attrs(mod
);
1817 module_param_sysfs_remove(mod
);
1819 kobject_put(mod
->holders_dir
);
1821 mod_kobject_put(mod
);
1826 static void mod_sysfs_fini(struct module
*mod
)
1828 remove_notes_attrs(mod
);
1829 remove_sect_attrs(mod
);
1830 mod_kobject_put(mod
);
1833 static void init_param_lock(struct module
*mod
)
1835 mutex_init(&mod
->param_lock
);
1837 #else /* !CONFIG_SYSFS */
1839 static int mod_sysfs_setup(struct module
*mod
,
1840 const struct load_info
*info
,
1841 struct kernel_param
*kparam
,
1842 unsigned int num_params
)
1847 static void mod_sysfs_fini(struct module
*mod
)
1851 static void module_remove_modinfo_attrs(struct module
*mod
)
1855 static void del_usage_links(struct module
*mod
)
1859 static void init_param_lock(struct module
*mod
)
1862 #endif /* CONFIG_SYSFS */
1864 static void mod_sysfs_teardown(struct module
*mod
)
1866 del_usage_links(mod
);
1867 module_remove_modinfo_attrs(mod
);
1868 module_param_sysfs_remove(mod
);
1869 kobject_put(mod
->mkobj
.drivers_dir
);
1870 kobject_put(mod
->holders_dir
);
1871 mod_sysfs_fini(mod
);
1874 #ifdef CONFIG_STRICT_MODULE_RWX
1876 * LKM RO/NX protection: protect module's text/ro-data
1877 * from modification and any data from execution.
1879 * General layout of module is:
1880 * [text] [read-only-data] [ro-after-init] [writable data]
1881 * text_size -----^ ^ ^ ^
1882 * ro_size ------------------------| | |
1883 * ro_after_init_size -----------------------------| |
1884 * size -----------------------------------------------------------|
1886 * These values are always page-aligned (as is base)
1888 static void frob_text(const struct module_layout
*layout
,
1889 int (*set_memory
)(unsigned long start
, int num_pages
))
1891 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1892 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1893 set_memory((unsigned long)layout
->base
,
1894 layout
->text_size
>> PAGE_SHIFT
);
1897 static void frob_rodata(const struct module_layout
*layout
,
1898 int (*set_memory
)(unsigned long start
, int num_pages
))
1900 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1901 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1902 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1903 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
1904 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
1907 static void frob_ro_after_init(const struct module_layout
*layout
,
1908 int (*set_memory
)(unsigned long start
, int num_pages
))
1910 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1911 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1912 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1913 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
1914 (layout
->ro_after_init_size
- layout
->ro_size
) >> PAGE_SHIFT
);
1917 static void frob_writable_data(const struct module_layout
*layout
,
1918 int (*set_memory
)(unsigned long start
, int num_pages
))
1920 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1921 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1922 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
1923 set_memory((unsigned long)layout
->base
+ layout
->ro_after_init_size
,
1924 (layout
->size
- layout
->ro_after_init_size
) >> PAGE_SHIFT
);
1927 /* livepatching wants to disable read-only so it can frob module. */
1928 void module_disable_ro(const struct module
*mod
)
1930 if (!rodata_enabled
)
1933 frob_text(&mod
->core_layout
, set_memory_rw
);
1934 frob_rodata(&mod
->core_layout
, set_memory_rw
);
1935 frob_ro_after_init(&mod
->core_layout
, set_memory_rw
);
1936 frob_text(&mod
->init_layout
, set_memory_rw
);
1937 frob_rodata(&mod
->init_layout
, set_memory_rw
);
1940 void module_enable_ro(const struct module
*mod
, bool after_init
)
1942 if (!rodata_enabled
)
1945 frob_text(&mod
->core_layout
, set_memory_ro
);
1946 frob_rodata(&mod
->core_layout
, set_memory_ro
);
1947 frob_text(&mod
->init_layout
, set_memory_ro
);
1948 frob_rodata(&mod
->init_layout
, set_memory_ro
);
1951 frob_ro_after_init(&mod
->core_layout
, set_memory_ro
);
1954 static void module_enable_nx(const struct module
*mod
)
1956 frob_rodata(&mod
->core_layout
, set_memory_nx
);
1957 frob_ro_after_init(&mod
->core_layout
, set_memory_nx
);
1958 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
1959 frob_rodata(&mod
->init_layout
, set_memory_nx
);
1960 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
1963 static void module_disable_nx(const struct module
*mod
)
1965 frob_rodata(&mod
->core_layout
, set_memory_x
);
1966 frob_ro_after_init(&mod
->core_layout
, set_memory_x
);
1967 frob_writable_data(&mod
->core_layout
, set_memory_x
);
1968 frob_rodata(&mod
->init_layout
, set_memory_x
);
1969 frob_writable_data(&mod
->init_layout
, set_memory_x
);
1972 /* Iterate through all modules and set each module's text as RW */
1973 void set_all_modules_text_rw(void)
1977 if (!rodata_enabled
)
1980 mutex_lock(&module_mutex
);
1981 list_for_each_entry_rcu(mod
, &modules
, list
) {
1982 if (mod
->state
== MODULE_STATE_UNFORMED
)
1985 frob_text(&mod
->core_layout
, set_memory_rw
);
1986 frob_text(&mod
->init_layout
, set_memory_rw
);
1988 mutex_unlock(&module_mutex
);
1991 /* Iterate through all modules and set each module's text as RO */
1992 void set_all_modules_text_ro(void)
1996 if (!rodata_enabled
)
1999 mutex_lock(&module_mutex
);
2000 list_for_each_entry_rcu(mod
, &modules
, list
) {
2002 * Ignore going modules since it's possible that ro
2003 * protection has already been disabled, otherwise we'll
2004 * run into protection faults at module deallocation.
2006 if (mod
->state
== MODULE_STATE_UNFORMED
||
2007 mod
->state
== MODULE_STATE_GOING
)
2010 frob_text(&mod
->core_layout
, set_memory_ro
);
2011 frob_text(&mod
->init_layout
, set_memory_ro
);
2013 mutex_unlock(&module_mutex
);
2016 static void disable_ro_nx(const struct module_layout
*layout
)
2018 if (rodata_enabled
) {
2019 frob_text(layout
, set_memory_rw
);
2020 frob_rodata(layout
, set_memory_rw
);
2021 frob_ro_after_init(layout
, set_memory_rw
);
2023 frob_rodata(layout
, set_memory_x
);
2024 frob_ro_after_init(layout
, set_memory_x
);
2025 frob_writable_data(layout
, set_memory_x
);
2029 static void disable_ro_nx(const struct module_layout
*layout
) { }
2030 static void module_enable_nx(const struct module
*mod
) { }
2031 static void module_disable_nx(const struct module
*mod
) { }
2034 #ifdef CONFIG_LIVEPATCH
2036 * Persist Elf information about a module. Copy the Elf header,
2037 * section header table, section string table, and symtab section
2038 * index from info to mod->klp_info.
2040 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2042 unsigned int size
, symndx
;
2045 size
= sizeof(*mod
->klp_info
);
2046 mod
->klp_info
= kmalloc(size
, GFP_KERNEL
);
2047 if (mod
->klp_info
== NULL
)
2051 size
= sizeof(mod
->klp_info
->hdr
);
2052 memcpy(&mod
->klp_info
->hdr
, info
->hdr
, size
);
2054 /* Elf section header table */
2055 size
= sizeof(*info
->sechdrs
) * info
->hdr
->e_shnum
;
2056 mod
->klp_info
->sechdrs
= kmalloc(size
, GFP_KERNEL
);
2057 if (mod
->klp_info
->sechdrs
== NULL
) {
2061 memcpy(mod
->klp_info
->sechdrs
, info
->sechdrs
, size
);
2063 /* Elf section name string table */
2064 size
= info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_size
;
2065 mod
->klp_info
->secstrings
= kmalloc(size
, GFP_KERNEL
);
2066 if (mod
->klp_info
->secstrings
== NULL
) {
2070 memcpy(mod
->klp_info
->secstrings
, info
->secstrings
, size
);
2072 /* Elf symbol section index */
2073 symndx
= info
->index
.sym
;
2074 mod
->klp_info
->symndx
= symndx
;
2077 * For livepatch modules, core_kallsyms.symtab is a complete
2078 * copy of the original symbol table. Adjust sh_addr to point
2079 * to core_kallsyms.symtab since the copy of the symtab in module
2080 * init memory is freed at the end of do_init_module().
2082 mod
->klp_info
->sechdrs
[symndx
].sh_addr
= \
2083 (unsigned long) mod
->core_kallsyms
.symtab
;
2088 kfree(mod
->klp_info
->sechdrs
);
2090 kfree(mod
->klp_info
);
2094 static void free_module_elf(struct module
*mod
)
2096 kfree(mod
->klp_info
->sechdrs
);
2097 kfree(mod
->klp_info
->secstrings
);
2098 kfree(mod
->klp_info
);
2100 #else /* !CONFIG_LIVEPATCH */
2101 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2106 static void free_module_elf(struct module
*mod
)
2109 #endif /* CONFIG_LIVEPATCH */
2111 void __weak
module_memfree(void *module_region
)
2113 vfree(module_region
);
2116 void __weak
module_arch_cleanup(struct module
*mod
)
2120 void __weak
module_arch_freeing_init(struct module
*mod
)
2124 static void cfi_cleanup(struct module
*mod
);
2126 /* Free a module, remove from lists, etc. */
2127 static void free_module(struct module
*mod
)
2129 trace_module_free(mod
);
2131 mod_sysfs_teardown(mod
);
2133 /* We leave it in list to prevent duplicate loads, but make sure
2134 * that noone uses it while it's being deconstructed. */
2135 mutex_lock(&module_mutex
);
2136 mod
->state
= MODULE_STATE_UNFORMED
;
2137 mutex_unlock(&module_mutex
);
2139 /* Remove dynamic debug info */
2140 ddebug_remove_module(mod
->name
);
2142 /* Arch-specific cleanup. */
2143 module_arch_cleanup(mod
);
2145 /* Module unload stuff */
2146 module_unload_free(mod
);
2148 /* Free any allocated parameters. */
2149 destroy_params(mod
->kp
, mod
->num_kp
);
2151 if (is_livepatch_module(mod
))
2152 free_module_elf(mod
);
2154 /* Now we can delete it from the lists */
2155 mutex_lock(&module_mutex
);
2156 /* Unlink carefully: kallsyms could be walking list. */
2157 list_del_rcu(&mod
->list
);
2158 mod_tree_remove(mod
);
2159 /* Remove this module from bug list, this uses list_del_rcu */
2160 module_bug_cleanup(mod
);
2161 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2162 synchronize_sched();
2163 mutex_unlock(&module_mutex
);
2165 /* This may be empty, but that's OK */
2166 disable_ro_nx(&mod
->init_layout
);
2168 /* Clean up CFI for the module. */
2171 module_arch_freeing_init(mod
);
2172 module_memfree(mod
->init_layout
.base
);
2174 percpu_modfree(mod
);
2176 /* Free lock-classes; relies on the preceding sync_rcu(). */
2177 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2179 /* Finally, free the core (containing the module structure) */
2180 disable_ro_nx(&mod
->core_layout
);
2181 module_memfree(mod
->core_layout
.base
);
2184 update_protections(current
->mm
);
2188 void *__symbol_get(const char *symbol
)
2190 struct module
*owner
;
2191 const struct kernel_symbol
*sym
;
2194 sym
= find_symbol(symbol
, &owner
, NULL
, true, true);
2195 if (sym
&& strong_try_module_get(owner
))
2199 return sym
? (void *)sym
->value
: NULL
;
2201 EXPORT_SYMBOL_GPL(__symbol_get
);
2204 * Ensure that an exported symbol [global namespace] does not already exist
2205 * in the kernel or in some other module's exported symbol table.
2207 * You must hold the module_mutex.
2209 static int verify_export_symbols(struct module
*mod
)
2212 struct module
*owner
;
2213 const struct kernel_symbol
*s
;
2215 const struct kernel_symbol
*sym
;
2218 { mod
->syms
, mod
->num_syms
},
2219 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2220 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2221 #ifdef CONFIG_UNUSED_SYMBOLS
2222 { mod
->unused_syms
, mod
->num_unused_syms
},
2223 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2227 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2228 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2229 if (find_symbol(s
->name
, &owner
, NULL
, true, false)) {
2230 pr_err("%s: exports duplicate symbol %s"
2232 mod
->name
, s
->name
, module_name(owner
));
2240 /* Change all symbols so that st_value encodes the pointer directly. */
2241 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2243 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2244 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2245 unsigned long secbase
;
2248 const struct kernel_symbol
*ksym
;
2250 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2251 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2253 switch (sym
[i
].st_shndx
) {
2255 /* Ignore common symbols */
2256 if (!strncmp(name
, "__gnu_lto", 9))
2259 /* We compiled with -fno-common. These are not
2260 supposed to happen. */
2261 pr_debug("Common symbol: %s\n", name
);
2262 pr_warn("%s: please compile with -fno-common\n",
2268 /* Don't need to do anything */
2269 pr_debug("Absolute symbol: 0x%08lx\n",
2270 (long)sym
[i
].st_value
);
2274 /* Livepatch symbols are resolved by livepatch */
2278 ksym
= resolve_symbol_wait(mod
, info
, name
);
2279 /* Ok if resolved. */
2280 if (ksym
&& !IS_ERR(ksym
)) {
2281 sym
[i
].st_value
= ksym
->value
;
2286 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2289 pr_warn("%s: Unknown symbol %s (err %li)\n",
2290 mod
->name
, name
, PTR_ERR(ksym
));
2291 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2295 /* Divert to percpu allocation if a percpu var. */
2296 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2297 secbase
= (unsigned long)mod_percpu(mod
);
2299 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2300 sym
[i
].st_value
+= secbase
;
2308 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2313 /* Now do relocations. */
2314 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2315 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2317 /* Not a valid relocation section? */
2318 if (infosec
>= info
->hdr
->e_shnum
)
2321 /* Don't bother with non-allocated sections */
2322 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2325 /* Livepatch relocation sections are applied by livepatch */
2326 if (info
->sechdrs
[i
].sh_flags
& SHF_RELA_LIVEPATCH
)
2329 if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2330 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2331 info
->index
.sym
, i
, mod
);
2332 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2333 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2334 info
->index
.sym
, i
, mod
);
2341 /* Additional bytes needed by arch in front of individual sections */
2342 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2343 unsigned int section
)
2345 /* default implementation just returns zero */
2349 /* Update size with this section: return offset. */
2350 static long get_offset(struct module
*mod
, unsigned int *size
,
2351 Elf_Shdr
*sechdr
, unsigned int section
)
2355 *size
+= arch_mod_section_prepend(mod
, section
);
2356 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2357 *size
= ret
+ sechdr
->sh_size
;
2361 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2362 might -- code, read-only data, read-write data, small data. Tally
2363 sizes, and place the offsets into sh_entsize fields: high bit means it
2365 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2367 static unsigned long const masks
[][2] = {
2368 /* NOTE: all executable code must be the first section
2369 * in this array; otherwise modify the text_size
2370 * finder in the two loops below */
2371 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2372 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2373 { SHF_RO_AFTER_INIT
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2374 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2375 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2379 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2380 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2382 pr_debug("Core section allocation order:\n");
2383 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2384 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2385 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2386 const char *sname
= info
->secstrings
+ s
->sh_name
;
2388 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2389 || (s
->sh_flags
& masks
[m
][1])
2390 || s
->sh_entsize
!= ~0UL
2391 || strstarts(sname
, ".init"))
2393 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2394 pr_debug("\t%s\n", sname
);
2397 case 0: /* executable */
2398 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2399 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2401 case 1: /* RO: text and ro-data */
2402 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2403 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2405 case 2: /* RO after init */
2406 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2407 mod
->core_layout
.ro_after_init_size
= mod
->core_layout
.size
;
2409 case 4: /* whole core */
2410 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2415 pr_debug("Init section allocation order:\n");
2416 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2417 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2418 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2419 const char *sname
= info
->secstrings
+ s
->sh_name
;
2421 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2422 || (s
->sh_flags
& masks
[m
][1])
2423 || s
->sh_entsize
!= ~0UL
2424 || !strstarts(sname
, ".init"))
2426 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2427 | INIT_OFFSET_MASK
);
2428 pr_debug("\t%s\n", sname
);
2431 case 0: /* executable */
2432 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2433 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2435 case 1: /* RO: text and ro-data */
2436 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2437 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2441 * RO after init doesn't apply to init_layout (only
2442 * core_layout), so it just takes the value of ro_size.
2444 mod
->init_layout
.ro_after_init_size
= mod
->init_layout
.ro_size
;
2446 case 4: /* whole init */
2447 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2453 static void set_license(struct module
*mod
, const char *license
)
2456 license
= "unspecified";
2458 if (!license_is_gpl_compatible(license
)) {
2459 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2460 pr_warn("%s: module license '%s' taints kernel.\n",
2461 mod
->name
, license
);
2462 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2463 LOCKDEP_NOW_UNRELIABLE
);
2467 /* Parse tag=value strings from .modinfo section */
2468 static char *next_string(char *string
, unsigned long *secsize
)
2470 /* Skip non-zero chars */
2473 if ((*secsize
)-- <= 1)
2477 /* Skip any zero padding. */
2478 while (!string
[0]) {
2480 if ((*secsize
)-- <= 1)
2486 static char *get_modinfo(struct load_info
*info
, const char *tag
)
2489 unsigned int taglen
= strlen(tag
);
2490 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2491 unsigned long size
= infosec
->sh_size
;
2493 for (p
= (char *)infosec
->sh_addr
; p
; p
= next_string(p
, &size
)) {
2494 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2495 return p
+ taglen
+ 1;
2500 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2502 struct module_attribute
*attr
;
2505 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2507 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2511 static void free_modinfo(struct module
*mod
)
2513 struct module_attribute
*attr
;
2516 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2522 #ifdef CONFIG_KALLSYMS
2524 /* lookup symbol in given range of kernel_symbols */
2525 static const struct kernel_symbol
*lookup_symbol(const char *name
,
2526 const struct kernel_symbol
*start
,
2527 const struct kernel_symbol
*stop
)
2529 return bsearch(name
, start
, stop
- start
,
2530 sizeof(struct kernel_symbol
), cmp_name
);
2533 static int is_exported(const char *name
, unsigned long value
,
2534 const struct module
*mod
)
2536 const struct kernel_symbol
*ks
;
2538 ks
= lookup_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2540 ks
= lookup_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2541 return ks
!= NULL
&& ks
->value
== value
;
2545 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2547 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2549 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2550 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2555 if (sym
->st_shndx
== SHN_UNDEF
)
2557 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2559 if (sym
->st_shndx
>= SHN_LORESERVE
)
2561 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2563 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2564 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2565 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2567 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2572 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2573 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2578 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2585 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2586 unsigned int shnum
, unsigned int pcpundx
)
2588 const Elf_Shdr
*sec
;
2590 if (src
->st_shndx
== SHN_UNDEF
2591 || src
->st_shndx
>= shnum
2595 #ifdef CONFIG_KALLSYMS_ALL
2596 if (src
->st_shndx
== pcpundx
)
2600 sec
= sechdrs
+ src
->st_shndx
;
2601 if (!(sec
->sh_flags
& SHF_ALLOC
)
2602 #ifndef CONFIG_KALLSYMS_ALL
2603 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2605 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2612 * We only allocate and copy the strings needed by the parts of symtab
2613 * we keep. This is simple, but has the effect of making multiple
2614 * copies of duplicates. We could be more sophisticated, see
2615 * linux-kernel thread starting with
2616 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2618 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2620 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2621 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2623 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2625 /* Put symbol section at end of init part of module. */
2626 symsect
->sh_flags
|= SHF_ALLOC
;
2627 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2628 info
->index
.sym
) | INIT_OFFSET_MASK
;
2629 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2631 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2632 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2634 /* Compute total space required for the core symbols' strtab. */
2635 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2636 if (i
== 0 || is_livepatch_module(mod
) ||
2637 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2638 info
->index
.pcpu
)) {
2639 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2644 /* Append room for core symbols at end of core part. */
2645 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2646 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2647 mod
->core_layout
.size
+= strtab_size
;
2648 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2650 /* Put string table section at end of init part of module. */
2651 strsect
->sh_flags
|= SHF_ALLOC
;
2652 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2653 info
->index
.str
) | INIT_OFFSET_MASK
;
2654 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2656 /* We'll tack temporary mod_kallsyms on the end. */
2657 mod
->init_layout
.size
= ALIGN(mod
->init_layout
.size
,
2658 __alignof__(struct mod_kallsyms
));
2659 info
->mod_kallsyms_init_off
= mod
->init_layout
.size
;
2660 mod
->init_layout
.size
+= sizeof(struct mod_kallsyms
);
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
;
2685 /* Set types up while we still have access to sections. */
2686 for (i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++)
2687 mod
->kallsyms
->symtab
[i
].st_info
2688 = elf_type(&mod
->kallsyms
->symtab
[i
], info
);
2690 /* Now populate the cut down core kallsyms for after init. */
2691 mod
->core_kallsyms
.symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2692 mod
->core_kallsyms
.strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2693 src
= mod
->kallsyms
->symtab
;
2694 for (ndst
= i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++) {
2695 if (i
== 0 || is_livepatch_module(mod
) ||
2696 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2697 info
->index
.pcpu
)) {
2699 dst
[ndst
++].st_name
= s
- mod
->core_kallsyms
.strtab
;
2700 s
+= strlcpy(s
, &mod
->kallsyms
->strtab
[src
[i
].st_name
],
2704 mod
->core_kallsyms
.num_symtab
= ndst
;
2707 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2711 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2714 #endif /* CONFIG_KALLSYMS */
2716 static void dynamic_debug_setup(struct module
*mod
, struct _ddebug
*debug
, unsigned int num
)
2720 #ifdef CONFIG_DYNAMIC_DEBUG
2721 if (ddebug_add_module(debug
, num
, mod
->name
))
2722 pr_err("dynamic debug error adding module: %s\n",
2727 static void dynamic_debug_remove(struct module
*mod
, struct _ddebug
*debug
)
2730 ddebug_remove_module(mod
->name
);
2733 void * __weak
module_alloc(unsigned long size
)
2735 return vmalloc_exec(size
);
2738 #ifdef CONFIG_DEBUG_KMEMLEAK
2739 static void kmemleak_load_module(const struct module
*mod
,
2740 const struct load_info
*info
)
2744 /* only scan the sections containing data */
2745 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2747 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2748 /* Scan all writable sections that's not executable */
2749 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2750 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2751 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2754 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2755 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2759 static inline void kmemleak_load_module(const struct module
*mod
,
2760 const struct load_info
*info
)
2765 #ifdef CONFIG_MODULE_SIG
2766 static int module_sig_check(struct load_info
*info
, int flags
)
2769 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2770 const void *mod
= info
->hdr
;
2773 * Require flags == 0, as a module with version information
2774 * removed is no longer the module that was signed
2777 info
->len
> markerlen
&&
2778 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2779 /* We truncate the module to discard the signature */
2780 info
->len
-= markerlen
;
2781 err
= mod_verify_sig(mod
, &info
->len
);
2785 info
->sig_ok
= true;
2789 /* Not having a signature is only an error if we're strict. */
2790 if (err
== -ENOKEY
&& !sig_enforce
)
2795 #else /* !CONFIG_MODULE_SIG */
2796 static int module_sig_check(struct load_info
*info
, int flags
)
2800 #endif /* !CONFIG_MODULE_SIG */
2802 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2803 static int elf_header_check(struct load_info
*info
)
2805 if (info
->len
< sizeof(*(info
->hdr
)))
2808 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2809 || info
->hdr
->e_type
!= ET_REL
2810 || !elf_check_arch(info
->hdr
)
2811 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2814 if (info
->hdr
->e_shoff
>= info
->len
2815 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2816 info
->len
- info
->hdr
->e_shoff
))
2822 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2824 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2827 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2829 if (copy_from_user(dst
, usrc
, n
) != 0)
2839 #ifdef CONFIG_LIVEPATCH
2840 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2842 if (get_modinfo(info
, "livepatch")) {
2844 add_taint_module(mod
, TAINT_LIVEPATCH
, LOCKDEP_STILL_OK
);
2845 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2851 #else /* !CONFIG_LIVEPATCH */
2852 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2854 if (get_modinfo(info
, "livepatch")) {
2855 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2862 #endif /* CONFIG_LIVEPATCH */
2864 static void check_modinfo_retpoline(struct module
*mod
, struct load_info
*info
)
2866 if (retpoline_module_ok(get_modinfo(info
, "retpoline")))
2869 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
2873 /* Sets info->hdr and info->len. */
2874 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
2875 struct load_info
*info
)
2880 if (info
->len
< sizeof(*(info
->hdr
)))
2883 err
= security_kernel_read_file(NULL
, READING_MODULE
);
2887 /* Suck in entire file: we'll want most of it. */
2888 info
->hdr
= __vmalloc(info
->len
,
2889 GFP_KERNEL
| __GFP_NOWARN
, PAGE_KERNEL
);
2893 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
2901 static void free_copy(struct load_info
*info
)
2906 static int rewrite_section_headers(struct load_info
*info
, int flags
)
2910 /* This should always be true, but let's be sure. */
2911 info
->sechdrs
[0].sh_addr
= 0;
2913 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2914 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
2915 if (shdr
->sh_type
!= SHT_NOBITS
2916 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
2917 pr_err("Module len %lu truncated\n", info
->len
);
2921 /* Mark all sections sh_addr with their address in the
2923 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
2925 #ifndef CONFIG_MODULE_UNLOAD
2926 /* Don't load .exit sections */
2927 if (strstarts(info
->secstrings
+shdr
->sh_name
, ".exit"))
2928 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2932 /* Track but don't keep modinfo and version sections. */
2933 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
2934 info
->index
.vers
= 0; /* Pretend no __versions section! */
2936 info
->index
.vers
= find_sec(info
, "__versions");
2937 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2939 info
->index
.info
= find_sec(info
, ".modinfo");
2940 if (!info
->index
.info
)
2941 info
->name
= "(missing .modinfo section)";
2943 info
->name
= get_modinfo(info
, "name");
2944 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2950 * Set up our basic convenience variables (pointers to section headers,
2951 * search for module section index etc), and do some basic section
2954 * Return the temporary module pointer (we'll replace it with the final
2955 * one when we move the module sections around).
2957 static struct module
*setup_load_info(struct load_info
*info
, int flags
)
2963 /* Set up the convenience variables */
2964 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
2965 info
->secstrings
= (void *)info
->hdr
2966 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
2968 err
= rewrite_section_headers(info
, flags
);
2970 return ERR_PTR(err
);
2972 /* Find internal symbols and strings. */
2973 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2974 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
2975 info
->index
.sym
= i
;
2976 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
2977 info
->strtab
= (char *)info
->hdr
2978 + info
->sechdrs
[info
->index
.str
].sh_offset
;
2983 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
2984 if (!info
->index
.mod
) {
2985 pr_warn("%s: No module found in object\n",
2986 info
->name
?: "(missing .modinfo name field)");
2987 return ERR_PTR(-ENOEXEC
);
2989 /* This is temporary: point mod into copy of data. */
2990 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
2993 * If we didn't load the .modinfo 'name' field, fall back to
2994 * on-disk struct mod 'name' field.
2997 info
->name
= mod
->name
;
2999 if (info
->index
.sym
== 0) {
3000 pr_warn("%s: module has no symbols (stripped?)\n", info
->name
);
3001 return ERR_PTR(-ENOEXEC
);
3004 info
->index
.pcpu
= find_pcpusec(info
);
3006 /* Check module struct version now, before we try to use module. */
3007 if (!check_modstruct_version(info
, mod
))
3008 return ERR_PTR(-ENOEXEC
);
3013 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
3015 const char *modmagic
= get_modinfo(info
, "vermagic");
3018 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
3021 /* This is allowed: modprobe --force will invalidate it. */
3023 err
= try_to_force_load(mod
, "bad vermagic");
3026 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
3027 pr_err("%s: version magic '%s' should be '%s'\n",
3028 info
->name
, modmagic
, vermagic
);
3032 if (!get_modinfo(info
, "intree")) {
3033 if (!test_taint(TAINT_OOT_MODULE
))
3034 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3036 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
3039 check_modinfo_retpoline(mod
, info
);
3041 if (get_modinfo(info
, "staging")) {
3042 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
3043 pr_warn("%s: module is from the staging directory, the quality "
3044 "is unknown, you have been warned.\n", mod
->name
);
3047 err
= check_modinfo_livepatch(mod
, info
);
3051 /* Set up license info based on the info section */
3052 set_license(mod
, get_modinfo(info
, "license"));
3057 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
3059 mod
->kp
= section_objs(info
, "__param",
3060 sizeof(*mod
->kp
), &mod
->num_kp
);
3061 mod
->syms
= section_objs(info
, "__ksymtab",
3062 sizeof(*mod
->syms
), &mod
->num_syms
);
3063 mod
->crcs
= section_addr(info
, "__kcrctab");
3064 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
3065 sizeof(*mod
->gpl_syms
),
3066 &mod
->num_gpl_syms
);
3067 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
3068 mod
->gpl_future_syms
= section_objs(info
,
3069 "__ksymtab_gpl_future",
3070 sizeof(*mod
->gpl_future_syms
),
3071 &mod
->num_gpl_future_syms
);
3072 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
3074 #ifdef CONFIG_UNUSED_SYMBOLS
3075 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
3076 sizeof(*mod
->unused_syms
),
3077 &mod
->num_unused_syms
);
3078 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
3079 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
3080 sizeof(*mod
->unused_gpl_syms
),
3081 &mod
->num_unused_gpl_syms
);
3082 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
3084 #ifdef CONFIG_CONSTRUCTORS
3085 mod
->ctors
= section_objs(info
, ".ctors",
3086 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3088 mod
->ctors
= section_objs(info
, ".init_array",
3089 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3090 else if (find_sec(info
, ".init_array")) {
3092 * This shouldn't happen with same compiler and binutils
3093 * building all parts of the module.
3095 pr_warn("%s: has both .ctors and .init_array.\n",
3101 #ifdef CONFIG_TRACEPOINTS
3102 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
3103 sizeof(*mod
->tracepoints_ptrs
),
3104 &mod
->num_tracepoints
);
3106 #ifdef HAVE_JUMP_LABEL
3107 mod
->jump_entries
= section_objs(info
, "__jump_table",
3108 sizeof(*mod
->jump_entries
),
3109 &mod
->num_jump_entries
);
3111 #ifdef CONFIG_EVENT_TRACING
3112 mod
->trace_events
= section_objs(info
, "_ftrace_events",
3113 sizeof(*mod
->trace_events
),
3114 &mod
->num_trace_events
);
3115 mod
->trace_evals
= section_objs(info
, "_ftrace_eval_map",
3116 sizeof(*mod
->trace_evals
),
3117 &mod
->num_trace_evals
);
3119 #ifdef CONFIG_TRACING
3120 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
3121 sizeof(*mod
->trace_bprintk_fmt_start
),
3122 &mod
->num_trace_bprintk_fmt
);
3124 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3125 /* sechdrs[0].sh_size is always zero */
3126 mod
->ftrace_callsites
= section_objs(info
, "__mcount_loc",
3127 sizeof(*mod
->ftrace_callsites
),
3128 &mod
->num_ftrace_callsites
);
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
)
3301 /* Module within temporary copy. */
3306 mod
= setup_load_info(info
, flags
);
3310 if (blacklisted(info
->name
))
3311 return ERR_PTR(-EPERM
);
3313 err
= check_modinfo(mod
, info
, flags
);
3315 return ERR_PTR(err
);
3317 /* Allow arches to frob section contents and sizes. */
3318 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3319 info
->secstrings
, mod
);
3321 return ERR_PTR(err
);
3323 /* We will do a special allocation for per-cpu sections later. */
3324 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3327 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3328 * layout_sections() can put it in the right place.
3329 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3331 ndx
= find_sec(info
, ".data..ro_after_init");
3333 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3335 /* Determine total sizes, and put offsets in sh_entsize. For now
3336 this is done generically; there doesn't appear to be any
3337 special cases for the architectures. */
3338 layout_sections(mod
, info
);
3339 layout_symtab(mod
, info
);
3341 /* Allocate and move to the final place */
3342 err
= move_module(mod
, info
);
3344 return ERR_PTR(err
);
3346 /* Module has been copied to its final place now: return it. */
3347 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3348 kmemleak_load_module(mod
, info
);
3352 /* mod is no longer valid after this! */
3353 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3355 percpu_modfree(mod
);
3356 module_arch_freeing_init(mod
);
3357 module_memfree(mod
->init_layout
.base
);
3358 module_memfree(mod
->core_layout
.base
);
3361 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3362 const Elf_Shdr
*sechdrs
,
3368 static void cfi_init(struct module
*mod
);
3370 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3372 /* Sort exception table now relocations are done. */
3373 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3375 /* Copy relocated percpu area over. */
3376 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3377 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3379 /* Setup kallsyms-specific fields. */
3380 add_kallsyms(mod
, info
);
3382 /* Setup CFI for the module. */
3385 /* Arch-specific module finalizing. */
3386 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3389 /* Is this module of this name done loading? No locks held. */
3390 static bool finished_loading(const char *name
)
3396 * The module_mutex should not be a heavily contended lock;
3397 * if we get the occasional sleep here, we'll go an extra iteration
3398 * in the wait_event_interruptible(), which is harmless.
3400 sched_annotate_sleep();
3401 mutex_lock(&module_mutex
);
3402 mod
= find_module_all(name
, strlen(name
), true);
3403 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
3404 || mod
->state
== MODULE_STATE_GOING
;
3405 mutex_unlock(&module_mutex
);
3410 /* Call module constructors. */
3411 static void do_mod_ctors(struct module
*mod
)
3413 #ifdef CONFIG_CONSTRUCTORS
3416 for (i
= 0; i
< mod
->num_ctors
; i
++)
3421 /* For freeing module_init on success, in case kallsyms traversing */
3422 struct mod_initfree
{
3423 struct rcu_head rcu
;
3427 static void do_free_init(struct rcu_head
*head
)
3429 struct mod_initfree
*m
= container_of(head
, struct mod_initfree
, rcu
);
3430 module_memfree(m
->module_init
);
3435 * This is where the real work happens.
3437 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3438 * helper command 'lx-symbols'.
3440 static noinline
int do_init_module(struct module
*mod
)
3443 struct mod_initfree
*freeinit
;
3445 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3450 freeinit
->module_init
= mod
->init_layout
.base
;
3453 * We want to find out whether @mod uses async during init. Clear
3454 * PF_USED_ASYNC. async_schedule*() will set it.
3456 current
->flags
&= ~PF_USED_ASYNC
;
3459 /* Start the module */
3460 if (mod
->init
!= NULL
)
3461 ret
= do_one_initcall(mod
->init
);
3463 goto fail_free_freeinit
;
3466 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3467 "follow 0/-E convention\n"
3468 "%s: loading module anyway...\n",
3469 __func__
, mod
->name
, ret
, __func__
);
3473 /* Now it's a first class citizen! */
3474 mod
->state
= MODULE_STATE_LIVE
;
3475 blocking_notifier_call_chain(&module_notify_list
,
3476 MODULE_STATE_LIVE
, mod
);
3479 * We need to finish all async code before the module init sequence
3480 * is done. This has potential to deadlock. For example, a newly
3481 * detected block device can trigger request_module() of the
3482 * default iosched from async probing task. Once userland helper
3483 * reaches here, async_synchronize_full() will wait on the async
3484 * task waiting on request_module() and deadlock.
3486 * This deadlock is avoided by perfomring async_synchronize_full()
3487 * iff module init queued any async jobs. This isn't a full
3488 * solution as it will deadlock the same if module loading from
3489 * async jobs nests more than once; however, due to the various
3490 * constraints, this hack seems to be the best option for now.
3491 * Please refer to the following thread for details.
3493 * http://thread.gmane.org/gmane.linux.kernel/1420814
3495 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3496 async_synchronize_full();
3498 mutex_lock(&module_mutex
);
3499 /* Drop initial reference. */
3501 trim_init_extable(mod
);
3502 #ifdef CONFIG_KALLSYMS
3503 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3504 rcu_assign_pointer(mod
->kallsyms
, &mod
->core_kallsyms
);
3506 module_enable_ro(mod
, true);
3507 mod_tree_remove_init(mod
);
3508 disable_ro_nx(&mod
->init_layout
);
3509 module_arch_freeing_init(mod
);
3510 mod
->init_layout
.base
= NULL
;
3511 mod
->init_layout
.size
= 0;
3512 mod
->init_layout
.ro_size
= 0;
3513 mod
->init_layout
.ro_after_init_size
= 0;
3514 mod
->init_layout
.text_size
= 0;
3516 * We want to free module_init, but be aware that kallsyms may be
3517 * walking this with preempt disabled. In all the failure paths, we
3518 * call synchronize_sched(), but we don't want to slow down the success
3519 * path, so use actual RCU here.
3520 * Note that module_alloc() on most architectures creates W+X page
3521 * mappings which won't be cleaned up until do_free_init() runs. Any
3522 * code such as mark_rodata_ro() which depends on those mappings to
3523 * be cleaned up needs to sync with the queued work - ie
3524 * rcu_barrier_sched()
3526 call_rcu_sched(&freeinit
->rcu
, do_free_init
);
3527 mutex_unlock(&module_mutex
);
3528 wake_up_all(&module_wq
);
3535 /* Try to protect us from buggy refcounters. */
3536 mod
->state
= MODULE_STATE_GOING
;
3537 synchronize_sched();
3539 blocking_notifier_call_chain(&module_notify_list
,
3540 MODULE_STATE_GOING
, mod
);
3541 klp_module_going(mod
);
3542 ftrace_release_mod(mod
);
3544 wake_up_all(&module_wq
);
3548 static int may_init_module(void)
3550 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3557 * We try to place it in the list now to make sure it's unique before
3558 * we dedicate too many resources. In particular, temporary percpu
3559 * memory exhaustion.
3561 static int add_unformed_module(struct module
*mod
)
3566 mod
->state
= MODULE_STATE_UNFORMED
;
3569 mutex_lock(&module_mutex
);
3570 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3572 if (old
->state
== MODULE_STATE_COMING
3573 || old
->state
== MODULE_STATE_UNFORMED
) {
3574 /* Wait in case it fails to load. */
3575 mutex_unlock(&module_mutex
);
3576 err
= wait_event_interruptible(module_wq
,
3577 finished_loading(mod
->name
));
3585 mod_update_bounds(mod
);
3586 list_add_rcu(&mod
->list
, &modules
);
3587 mod_tree_insert(mod
);
3591 mutex_unlock(&module_mutex
);
3596 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3600 mutex_lock(&module_mutex
);
3602 /* Find duplicate symbols (must be called under lock). */
3603 err
= verify_export_symbols(mod
);
3607 /* This relies on module_mutex for list integrity. */
3608 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3610 module_enable_ro(mod
, false);
3611 module_enable_nx(mod
);
3613 /* Mark state as coming so strong_try_module_get() ignores us,
3614 * but kallsyms etc. can see us. */
3615 mod
->state
= MODULE_STATE_COMING
;
3616 mutex_unlock(&module_mutex
);
3621 mutex_unlock(&module_mutex
);
3625 static int prepare_coming_module(struct module
*mod
)
3629 ftrace_module_enable(mod
);
3630 err
= klp_module_coming(mod
);
3634 blocking_notifier_call_chain(&module_notify_list
,
3635 MODULE_STATE_COMING
, mod
);
3639 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3642 struct module
*mod
= arg
;
3645 if (strcmp(param
, "async_probe") == 0) {
3646 mod
->async_probe_requested
= true;
3650 /* Check for magic 'dyndbg' arg */
3651 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3653 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3657 /* Allocate and load the module: note that size of section 0 is always
3658 zero, and we rely on this for optional sections. */
3659 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3666 err
= module_sig_check(info
, flags
);
3670 err
= elf_header_check(info
);
3674 /* Figure out module layout, and allocate all the memory. */
3675 mod
= layout_and_allocate(info
, flags
);
3681 audit_log_kern_module(mod
->name
);
3683 /* Reserve our place in the list. */
3684 err
= add_unformed_module(mod
);
3688 #ifdef CONFIG_MODULE_SIG
3689 mod
->sig_ok
= info
->sig_ok
;
3691 pr_notice_once("%s: module verification failed: signature "
3692 "and/or required key missing - tainting "
3693 "kernel\n", mod
->name
);
3694 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3698 /* To avoid stressing percpu allocator, do this once we're unique. */
3699 err
= percpu_modalloc(mod
, info
);
3703 /* Now module is in final location, initialize linked lists, etc. */
3704 err
= module_unload_init(mod
);
3708 init_param_lock(mod
);
3710 /* Now we've got everything in the final locations, we can
3711 * find optional sections. */
3712 err
= find_module_sections(mod
, info
);
3716 err
= check_module_license_and_versions(mod
);
3720 /* Set up MODINFO_ATTR fields */
3721 setup_modinfo(mod
, info
);
3723 /* Fix up syms, so that st_value is a pointer to location. */
3724 err
= simplify_symbols(mod
, info
);
3728 err
= apply_relocations(mod
, info
);
3732 err
= post_relocation(mod
, info
);
3736 flush_module_icache(mod
);
3738 /* Now copy in args */
3739 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3740 if (IS_ERR(mod
->args
)) {
3741 err
= PTR_ERR(mod
->args
);
3742 goto free_arch_cleanup
;
3745 dynamic_debug_setup(mod
, info
->debug
, info
->num_debug
);
3747 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3748 ftrace_module_init(mod
);
3750 /* Finally it's fully formed, ready to start executing. */
3751 err
= complete_formation(mod
, info
);
3753 goto ddebug_cleanup
;
3755 err
= prepare_coming_module(mod
);
3759 /* Module is ready to execute: parsing args may do that. */
3760 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3762 unknown_module_param_cb
);
3763 if (IS_ERR(after_dashes
)) {
3764 err
= PTR_ERR(after_dashes
);
3765 goto coming_cleanup
;
3766 } else if (after_dashes
) {
3767 pr_warn("%s: parameters '%s' after `--' ignored\n",
3768 mod
->name
, after_dashes
);
3771 /* Link in to sysfs. */
3772 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3774 goto coming_cleanup
;
3776 if (is_livepatch_module(mod
)) {
3777 err
= copy_module_elf(mod
, info
);
3782 /* Get rid of temporary copy. */
3786 trace_module_load(mod
);
3788 return do_init_module(mod
);
3791 mod_sysfs_teardown(mod
);
3793 mod
->state
= MODULE_STATE_GOING
;
3794 destroy_params(mod
->kp
, mod
->num_kp
);
3795 blocking_notifier_call_chain(&module_notify_list
,
3796 MODULE_STATE_GOING
, mod
);
3797 klp_module_going(mod
);
3799 /* module_bug_cleanup needs module_mutex protection */
3800 mutex_lock(&module_mutex
);
3801 module_bug_cleanup(mod
);
3802 mutex_unlock(&module_mutex
);
3804 /* we can't deallocate the module until we clear memory protection */
3805 module_disable_ro(mod
);
3806 module_disable_nx(mod
);
3809 dynamic_debug_remove(mod
, info
->debug
);
3810 synchronize_sched();
3813 module_arch_cleanup(mod
);
3817 module_unload_free(mod
);
3819 mutex_lock(&module_mutex
);
3820 /* Unlink carefully: kallsyms could be walking list. */
3821 list_del_rcu(&mod
->list
);
3822 mod_tree_remove(mod
);
3823 wake_up_all(&module_wq
);
3824 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3825 synchronize_sched();
3826 mutex_unlock(&module_mutex
);
3829 * Ftrace needs to clean up what it initialized.
3830 * This does nothing if ftrace_module_init() wasn't called,
3831 * but it must be called outside of module_mutex.
3833 ftrace_release_mod(mod
);
3834 /* Free lock-classes; relies on the preceding sync_rcu() */
3835 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
3837 module_deallocate(mod
, info
);
3843 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
3844 unsigned long, len
, const char __user
*, uargs
)
3847 struct load_info info
= { };
3849 err
= may_init_module();
3853 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3856 err
= copy_module_from_user(umod
, len
, &info
);
3860 return load_module(&info
, uargs
, 0);
3863 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
3865 struct load_info info
= { };
3870 err
= may_init_module();
3874 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
3876 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
3877 |MODULE_INIT_IGNORE_VERMAGIC
))
3880 err
= kernel_read_file_from_fd(fd
, &hdr
, &size
, INT_MAX
,
3887 return load_module(&info
, uargs
, flags
);
3890 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
3892 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
3895 #ifdef CONFIG_KALLSYMS
3897 * This ignores the intensely annoying "mapping symbols" found
3898 * in ARM ELF files: $a, $t and $d.
3900 static inline int is_arm_mapping_symbol(const char *str
)
3902 if (str
[0] == '.' && str
[1] == 'L')
3904 return str
[0] == '$' && strchr("axtd", str
[1])
3905 && (str
[2] == '\0' || str
[2] == '.');
3908 static const char *symname(struct mod_kallsyms
*kallsyms
, unsigned int symnum
)
3910 return kallsyms
->strtab
+ kallsyms
->symtab
[symnum
].st_name
;
3913 static const char *get_ksymbol(struct module
*mod
,
3915 unsigned long *size
,
3916 unsigned long *offset
)
3918 unsigned int i
, best
= 0;
3919 unsigned long nextval
;
3920 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
3922 /* At worse, next value is at end of module */
3923 if (within_module_init(addr
, mod
))
3924 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
3926 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
3928 /* Scan for closest preceding symbol, and next symbol. (ELF
3929 starts real symbols at 1). */
3930 for (i
= 1; i
< kallsyms
->num_symtab
; i
++) {
3931 if (kallsyms
->symtab
[i
].st_shndx
== SHN_UNDEF
)
3934 /* We ignore unnamed symbols: they're uninformative
3935 * and inserted at a whim. */
3936 if (*symname(kallsyms
, i
) == '\0'
3937 || is_arm_mapping_symbol(symname(kallsyms
, i
)))
3940 if (kallsyms
->symtab
[i
].st_value
<= addr
3941 && kallsyms
->symtab
[i
].st_value
> kallsyms
->symtab
[best
].st_value
)
3943 if (kallsyms
->symtab
[i
].st_value
> addr
3944 && kallsyms
->symtab
[i
].st_value
< nextval
)
3945 nextval
= kallsyms
->symtab
[i
].st_value
;
3952 *size
= nextval
- kallsyms
->symtab
[best
].st_value
;
3954 *offset
= addr
- kallsyms
->symtab
[best
].st_value
;
3955 return symname(kallsyms
, best
);
3958 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3959 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3960 const char *module_address_lookup(unsigned long addr
,
3961 unsigned long *size
,
3962 unsigned long *offset
,
3966 const char *ret
= NULL
;
3970 mod
= __module_address(addr
);
3973 *modname
= mod
->name
;
3974 ret
= get_ksymbol(mod
, addr
, size
, offset
);
3976 /* Make a copy in here where it's safe */
3978 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
3986 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
3991 list_for_each_entry_rcu(mod
, &modules
, list
) {
3992 if (mod
->state
== MODULE_STATE_UNFORMED
)
3994 if (within_module(addr
, mod
)) {
3997 sym
= get_ksymbol(mod
, addr
, NULL
, NULL
);
4000 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
4010 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
4011 unsigned long *offset
, char *modname
, char *name
)
4016 list_for_each_entry_rcu(mod
, &modules
, list
) {
4017 if (mod
->state
== MODULE_STATE_UNFORMED
)
4019 if (within_module(addr
, mod
)) {
4022 sym
= get_ksymbol(mod
, addr
, size
, offset
);
4026 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
4028 strlcpy(name
, sym
, KSYM_NAME_LEN
);
4038 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
4039 char *name
, char *module_name
, int *exported
)
4044 list_for_each_entry_rcu(mod
, &modules
, list
) {
4045 struct mod_kallsyms
*kallsyms
;
4047 if (mod
->state
== MODULE_STATE_UNFORMED
)
4049 kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4050 if (symnum
< kallsyms
->num_symtab
) {
4051 *value
= kallsyms
->symtab
[symnum
].st_value
;
4052 *type
= kallsyms
->symtab
[symnum
].st_info
;
4053 strlcpy(name
, symname(kallsyms
, symnum
), KSYM_NAME_LEN
);
4054 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
4055 *exported
= is_exported(name
, *value
, mod
);
4059 symnum
-= kallsyms
->num_symtab
;
4065 static unsigned long mod_find_symname(struct module
*mod
, const char *name
)
4068 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4070 for (i
= 0; i
< kallsyms
->num_symtab
; i
++)
4071 if (strcmp(name
, symname(kallsyms
, i
)) == 0 &&
4072 kallsyms
->symtab
[i
].st_shndx
!= SHN_UNDEF
)
4073 return kallsyms
->symtab
[i
].st_value
;
4077 /* Look for this name: can be of form module:name. */
4078 unsigned long module_kallsyms_lookup_name(const char *name
)
4082 unsigned long ret
= 0;
4084 /* Don't lock: we're in enough trouble already. */
4086 if ((colon
= strnchr(name
, MODULE_NAME_LEN
, ':')) != NULL
) {
4087 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
4088 ret
= mod_find_symname(mod
, colon
+1);
4090 list_for_each_entry_rcu(mod
, &modules
, list
) {
4091 if (mod
->state
== MODULE_STATE_UNFORMED
)
4093 if ((ret
= mod_find_symname(mod
, name
)) != 0)
4101 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
4102 struct module
*, unsigned long),
4109 module_assert_mutex();
4111 list_for_each_entry(mod
, &modules
, list
) {
4112 /* We hold module_mutex: no need for rcu_dereference_sched */
4113 struct mod_kallsyms
*kallsyms
= mod
->kallsyms
;
4115 if (mod
->state
== MODULE_STATE_UNFORMED
)
4117 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4119 if (kallsyms
->symtab
[i
].st_shndx
== SHN_UNDEF
)
4122 ret
= fn(data
, symname(kallsyms
, i
),
4123 mod
, kallsyms
->symtab
[i
].st_value
);
4130 #endif /* CONFIG_KALLSYMS */
4132 static void cfi_init(struct module
*mod
)
4134 #ifdef CONFIG_CFI_CLANG
4136 (cfi_check_fn
)mod_find_symname(mod
, CFI_CHECK_FN_NAME
);
4137 cfi_module_add(mod
, module_addr_min
, module_addr_max
);
4141 static void cfi_cleanup(struct module
*mod
)
4143 #ifdef CONFIG_CFI_CLANG
4144 cfi_module_remove(mod
, module_addr_min
, module_addr_max
);
4148 /* Maximum number of characters written by module_flags() */
4149 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4151 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4152 static char *module_flags(struct module
*mod
, char *buf
)
4156 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
4158 mod
->state
== MODULE_STATE_GOING
||
4159 mod
->state
== MODULE_STATE_COMING
) {
4161 bx
+= module_flags_taint(mod
, buf
+ bx
);
4162 /* Show a - for module-is-being-unloaded */
4163 if (mod
->state
== MODULE_STATE_GOING
)
4165 /* Show a + for module-is-being-loaded */
4166 if (mod
->state
== MODULE_STATE_COMING
)
4175 #ifdef CONFIG_PROC_FS
4176 /* Called by the /proc file system to return a list of modules. */
4177 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
4179 mutex_lock(&module_mutex
);
4180 return seq_list_start(&modules
, *pos
);
4183 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
4185 return seq_list_next(p
, &modules
, pos
);
4188 static void m_stop(struct seq_file
*m
, void *p
)
4190 mutex_unlock(&module_mutex
);
4193 static int m_show(struct seq_file
*m
, void *p
)
4195 struct module
*mod
= list_entry(p
, struct module
, list
);
4196 char buf
[MODULE_FLAGS_BUF_SIZE
];
4198 /* We always ignore unformed modules. */
4199 if (mod
->state
== MODULE_STATE_UNFORMED
)
4202 seq_printf(m
, "%s %u",
4203 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
4204 print_unload_info(m
, mod
);
4206 /* Informative for users. */
4207 seq_printf(m
, " %s",
4208 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
4209 mod
->state
== MODULE_STATE_COMING
? "Loading" :
4211 /* Used by oprofile and other similar tools. */
4212 seq_printf(m
, " 0x%pK", mod
->core_layout
.base
);
4216 seq_printf(m
, " %s", module_flags(mod
, buf
));
4222 /* Format: modulename size refcount deps address
4224 Where refcount is a number or -, and deps is a comma-separated list
4227 static const struct seq_operations modules_op
= {
4234 static int modules_open(struct inode
*inode
, struct file
*file
)
4236 return seq_open(file
, &modules_op
);
4239 static const struct file_operations proc_modules_operations
= {
4240 .open
= modules_open
,
4242 .llseek
= seq_lseek
,
4243 .release
= seq_release
,
4246 static int __init
proc_modules_init(void)
4248 proc_create("modules", 0, NULL
, &proc_modules_operations
);
4251 module_init(proc_modules_init
);
4254 /* Given an address, look for it in the module exception tables. */
4255 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
4257 const struct exception_table_entry
*e
= NULL
;
4261 mod
= __module_address(addr
);
4265 if (!mod
->num_exentries
)
4268 e
= search_extable(mod
->extable
,
4275 * Now, if we found one, we are running inside it now, hence
4276 * we cannot unload the module, hence no refcnt needed.
4282 * is_module_address - is this address inside a module?
4283 * @addr: the address to check.
4285 * See is_module_text_address() if you simply want to see if the address
4286 * is code (not data).
4288 bool is_module_address(unsigned long addr
)
4293 ret
= __module_address(addr
) != NULL
;
4300 * __module_address - get the module which contains an address.
4301 * @addr: the address.
4303 * Must be called with preempt disabled or module mutex held so that
4304 * module doesn't get freed during this.
4306 struct module
*__module_address(unsigned long addr
)
4310 if (addr
< module_addr_min
|| addr
> module_addr_max
)
4313 module_assert_mutex_or_preempt();
4315 mod
= mod_find(addr
);
4317 BUG_ON(!within_module(addr
, mod
));
4318 if (mod
->state
== MODULE_STATE_UNFORMED
)
4323 EXPORT_SYMBOL_GPL(__module_address
);
4326 * is_module_text_address - is this address inside module code?
4327 * @addr: the address to check.
4329 * See is_module_address() if you simply want to see if the address is
4330 * anywhere in a module. See kernel_text_address() for testing if an
4331 * address corresponds to kernel or module code.
4333 bool is_module_text_address(unsigned long addr
)
4338 ret
= __module_text_address(addr
) != NULL
;
4345 * __module_text_address - get the module whose code contains an address.
4346 * @addr: the address.
4348 * Must be called with preempt disabled or module mutex held so that
4349 * module doesn't get freed during this.
4351 struct module
*__module_text_address(unsigned long addr
)
4353 struct module
*mod
= __module_address(addr
);
4355 /* Make sure it's within the text section. */
4356 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4357 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4362 EXPORT_SYMBOL_GPL(__module_text_address
);
4364 /* Don't grab lock, we're oopsing. */
4365 void print_modules(void)
4368 char buf
[MODULE_FLAGS_BUF_SIZE
];
4370 printk(KERN_DEFAULT
"Modules linked in:");
4371 /* Most callers should already have preempt disabled, but make sure */
4373 list_for_each_entry_rcu(mod
, &modules
, list
) {
4374 if (mod
->state
== MODULE_STATE_UNFORMED
)
4376 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4379 if (last_unloaded_module
[0])
4380 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4384 #ifdef CONFIG_MODVERSIONS
4385 /* Generate the signature for all relevant module structures here.
4386 * If these change, we don't want to try to parse the module. */
4387 void module_layout(struct module
*mod
,
4388 struct modversion_info
*ver
,
4389 struct kernel_param
*kp
,
4390 struct kernel_symbol
*ks
,
4391 struct tracepoint
* const *tp
)
4394 EXPORT_SYMBOL(module_layout
);