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 */
282 * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
283 * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
285 bool is_module_sig_enforced(void)
289 EXPORT_SYMBOL(is_module_sig_enforced
);
291 /* Block module loading/unloading? */
292 int modules_disabled
= 0;
293 core_param(nomodule
, modules_disabled
, bint
, 0);
295 /* Waiting for a module to finish initializing? */
296 static DECLARE_WAIT_QUEUE_HEAD(module_wq
);
298 static BLOCKING_NOTIFIER_HEAD(module_notify_list
);
300 int register_module_notifier(struct notifier_block
*nb
)
302 return blocking_notifier_chain_register(&module_notify_list
, nb
);
304 EXPORT_SYMBOL(register_module_notifier
);
306 int unregister_module_notifier(struct notifier_block
*nb
)
308 return blocking_notifier_chain_unregister(&module_notify_list
, nb
);
310 EXPORT_SYMBOL(unregister_module_notifier
);
317 char *secstrings
, *strtab
;
318 unsigned long symoffs
, stroffs
;
319 struct _ddebug
*debug
;
320 unsigned int num_debug
;
322 #ifdef CONFIG_KALLSYMS
323 unsigned long mod_kallsyms_init_off
;
326 unsigned int sym
, str
, mod
, vers
, info
, pcpu
;
331 * We require a truly strong try_module_get(): 0 means success.
332 * Otherwise an error is returned due to ongoing or failed
333 * initialization etc.
335 static inline int strong_try_module_get(struct module
*mod
)
337 BUG_ON(mod
&& mod
->state
== MODULE_STATE_UNFORMED
);
338 if (mod
&& mod
->state
== MODULE_STATE_COMING
)
340 if (try_module_get(mod
))
346 static inline void add_taint_module(struct module
*mod
, unsigned flag
,
347 enum lockdep_ok lockdep_ok
)
349 add_taint(flag
, lockdep_ok
);
350 set_bit(flag
, &mod
->taints
);
354 * A thread that wants to hold a reference to a module only while it
355 * is running can call this to safely exit. nfsd and lockd use this.
357 void __noreturn
__module_put_and_exit(struct module
*mod
, long code
)
362 EXPORT_SYMBOL(__module_put_and_exit
);
364 /* Find a module section: 0 means not found. */
365 static unsigned int find_sec(const struct load_info
*info
, const char *name
)
369 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
370 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
371 /* Alloc bit cleared means "ignore it." */
372 if ((shdr
->sh_flags
& SHF_ALLOC
)
373 && strcmp(info
->secstrings
+ shdr
->sh_name
, name
) == 0)
379 /* Find a module section, or NULL. */
380 static void *section_addr(const struct load_info
*info
, const char *name
)
382 /* Section 0 has sh_addr 0. */
383 return (void *)info
->sechdrs
[find_sec(info
, name
)].sh_addr
;
386 /* Find a module section, or NULL. Fill in number of "objects" in section. */
387 static void *section_objs(const struct load_info
*info
,
392 unsigned int sec
= find_sec(info
, name
);
394 /* Section 0 has sh_addr 0 and sh_size 0. */
395 *num
= info
->sechdrs
[sec
].sh_size
/ object_size
;
396 return (void *)info
->sechdrs
[sec
].sh_addr
;
399 /* Provided by the linker */
400 extern const struct kernel_symbol __start___ksymtab
[];
401 extern const struct kernel_symbol __stop___ksymtab
[];
402 extern const struct kernel_symbol __start___ksymtab_gpl
[];
403 extern const struct kernel_symbol __stop___ksymtab_gpl
[];
404 extern const struct kernel_symbol __start___ksymtab_gpl_future
[];
405 extern const struct kernel_symbol __stop___ksymtab_gpl_future
[];
406 extern const s32 __start___kcrctab
[];
407 extern const s32 __start___kcrctab_gpl
[];
408 extern const s32 __start___kcrctab_gpl_future
[];
409 #ifdef CONFIG_UNUSED_SYMBOLS
410 extern const struct kernel_symbol __start___ksymtab_unused
[];
411 extern const struct kernel_symbol __stop___ksymtab_unused
[];
412 extern const struct kernel_symbol __start___ksymtab_unused_gpl
[];
413 extern const struct kernel_symbol __stop___ksymtab_unused_gpl
[];
414 extern const s32 __start___kcrctab_unused
[];
415 extern const s32 __start___kcrctab_unused_gpl
[];
418 #ifndef CONFIG_MODVERSIONS
419 #define symversion(base, idx) NULL
421 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
424 static bool each_symbol_in_section(const struct symsearch
*arr
,
425 unsigned int arrsize
,
426 struct module
*owner
,
427 bool (*fn
)(const struct symsearch
*syms
,
428 struct module
*owner
,
434 for (j
= 0; j
< arrsize
; j
++) {
435 if (fn(&arr
[j
], owner
, data
))
442 /* Returns true as soon as fn returns true, otherwise false. */
443 bool each_symbol_section(bool (*fn
)(const struct symsearch
*arr
,
444 struct module
*owner
,
449 static const struct symsearch arr
[] = {
450 { __start___ksymtab
, __stop___ksymtab
, __start___kcrctab
,
451 NOT_GPL_ONLY
, false },
452 { __start___ksymtab_gpl
, __stop___ksymtab_gpl
,
453 __start___kcrctab_gpl
,
455 { __start___ksymtab_gpl_future
, __stop___ksymtab_gpl_future
,
456 __start___kcrctab_gpl_future
,
457 WILL_BE_GPL_ONLY
, false },
458 #ifdef CONFIG_UNUSED_SYMBOLS
459 { __start___ksymtab_unused
, __stop___ksymtab_unused
,
460 __start___kcrctab_unused
,
461 NOT_GPL_ONLY
, true },
462 { __start___ksymtab_unused_gpl
, __stop___ksymtab_unused_gpl
,
463 __start___kcrctab_unused_gpl
,
468 module_assert_mutex_or_preempt();
470 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), NULL
, fn
, data
))
473 list_for_each_entry_rcu(mod
, &modules
, list
) {
474 struct symsearch arr
[] = {
475 { mod
->syms
, mod
->syms
+ mod
->num_syms
, mod
->crcs
,
476 NOT_GPL_ONLY
, false },
477 { mod
->gpl_syms
, mod
->gpl_syms
+ mod
->num_gpl_syms
,
480 { mod
->gpl_future_syms
,
481 mod
->gpl_future_syms
+ mod
->num_gpl_future_syms
,
482 mod
->gpl_future_crcs
,
483 WILL_BE_GPL_ONLY
, false },
484 #ifdef CONFIG_UNUSED_SYMBOLS
486 mod
->unused_syms
+ mod
->num_unused_syms
,
488 NOT_GPL_ONLY
, true },
489 { mod
->unused_gpl_syms
,
490 mod
->unused_gpl_syms
+ mod
->num_unused_gpl_syms
,
491 mod
->unused_gpl_crcs
,
496 if (mod
->state
== MODULE_STATE_UNFORMED
)
499 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), mod
, fn
, data
))
504 EXPORT_SYMBOL_GPL(each_symbol_section
);
506 struct find_symbol_arg
{
513 struct module
*owner
;
515 const struct kernel_symbol
*sym
;
518 static bool check_symbol(const struct symsearch
*syms
,
519 struct module
*owner
,
520 unsigned int symnum
, void *data
)
522 struct find_symbol_arg
*fsa
= data
;
525 if (syms
->licence
== GPL_ONLY
)
527 if (syms
->licence
== WILL_BE_GPL_ONLY
&& fsa
->warn
) {
528 pr_warn("Symbol %s is being used by a non-GPL module, "
529 "which will not be allowed in the future\n",
534 #ifdef CONFIG_UNUSED_SYMBOLS
535 if (syms
->unused
&& fsa
->warn
) {
536 pr_warn("Symbol %s is marked as UNUSED, however this module is "
537 "using it.\n", fsa
->name
);
538 pr_warn("This symbol will go away in the future.\n");
539 pr_warn("Please evaluate if this is the right api to use and "
540 "if it really is, submit a report to the linux kernel "
541 "mailing list together with submitting your code for "
547 fsa
->crc
= symversion(syms
->crcs
, symnum
);
548 fsa
->sym
= &syms
->start
[symnum
];
552 static int cmp_name(const void *va
, const void *vb
)
555 const struct kernel_symbol
*b
;
557 return strcmp(a
, b
->name
);
560 static bool find_symbol_in_section(const struct symsearch
*syms
,
561 struct module
*owner
,
564 struct find_symbol_arg
*fsa
= data
;
565 struct kernel_symbol
*sym
;
567 sym
= bsearch(fsa
->name
, syms
->start
, syms
->stop
- syms
->start
,
568 sizeof(struct kernel_symbol
), cmp_name
);
570 if (sym
!= NULL
&& check_symbol(syms
, owner
, sym
- syms
->start
, data
))
576 /* Find a symbol and return it, along with, (optional) crc and
577 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
578 const struct kernel_symbol
*find_symbol(const char *name
,
579 struct module
**owner
,
584 struct find_symbol_arg fsa
;
590 if (each_symbol_section(find_symbol_in_section
, &fsa
)) {
598 pr_debug("Failed to find symbol %s\n", name
);
601 EXPORT_SYMBOL_GPL(find_symbol
);
604 * Search for module by name: must hold module_mutex (or preempt disabled
605 * for read-only access).
607 static struct module
*find_module_all(const char *name
, size_t len
,
612 module_assert_mutex_or_preempt();
614 list_for_each_entry_rcu(mod
, &modules
, list
) {
615 if (!even_unformed
&& mod
->state
== MODULE_STATE_UNFORMED
)
617 if (strlen(mod
->name
) == len
&& !memcmp(mod
->name
, name
, len
))
623 struct module
*find_module(const char *name
)
625 module_assert_mutex();
626 return find_module_all(name
, strlen(name
), false);
628 EXPORT_SYMBOL_GPL(find_module
);
632 static inline void __percpu
*mod_percpu(struct module
*mod
)
637 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
639 Elf_Shdr
*pcpusec
= &info
->sechdrs
[info
->index
.pcpu
];
640 unsigned long align
= pcpusec
->sh_addralign
;
642 if (!pcpusec
->sh_size
)
645 if (align
> PAGE_SIZE
) {
646 pr_warn("%s: per-cpu alignment %li > %li\n",
647 mod
->name
, align
, PAGE_SIZE
);
651 mod
->percpu
= __alloc_reserved_percpu(pcpusec
->sh_size
, align
);
653 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
654 mod
->name
, (unsigned long)pcpusec
->sh_size
);
657 mod
->percpu_size
= pcpusec
->sh_size
;
661 static void percpu_modfree(struct module
*mod
)
663 free_percpu(mod
->percpu
);
666 static unsigned int find_pcpusec(struct load_info
*info
)
668 return find_sec(info
, ".data..percpu");
671 static void percpu_modcopy(struct module
*mod
,
672 const void *from
, unsigned long size
)
676 for_each_possible_cpu(cpu
)
677 memcpy(per_cpu_ptr(mod
->percpu
, cpu
), from
, size
);
680 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
687 list_for_each_entry_rcu(mod
, &modules
, list
) {
688 if (mod
->state
== MODULE_STATE_UNFORMED
)
690 if (!mod
->percpu_size
)
692 for_each_possible_cpu(cpu
) {
693 void *start
= per_cpu_ptr(mod
->percpu
, cpu
);
694 void *va
= (void *)addr
;
696 if (va
>= start
&& va
< start
+ mod
->percpu_size
) {
698 *can_addr
= (unsigned long) (va
- start
);
699 *can_addr
+= (unsigned long)
700 per_cpu_ptr(mod
->percpu
,
714 * is_module_percpu_address - test whether address is from module static percpu
715 * @addr: address to test
717 * Test whether @addr belongs to module static percpu area.
720 * %true if @addr is from module static percpu area
722 bool is_module_percpu_address(unsigned long addr
)
724 return __is_module_percpu_address(addr
, NULL
);
727 #else /* ... !CONFIG_SMP */
729 static inline void __percpu
*mod_percpu(struct module
*mod
)
733 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
735 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
736 if (info
->sechdrs
[info
->index
.pcpu
].sh_size
!= 0)
740 static inline void percpu_modfree(struct module
*mod
)
743 static unsigned int find_pcpusec(struct load_info
*info
)
747 static inline void percpu_modcopy(struct module
*mod
,
748 const void *from
, unsigned long size
)
750 /* pcpusec should be 0, and size of that section should be 0. */
753 bool is_module_percpu_address(unsigned long addr
)
758 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
763 #endif /* CONFIG_SMP */
765 #define MODINFO_ATTR(field) \
766 static void setup_modinfo_##field(struct module *mod, const char *s) \
768 mod->field = kstrdup(s, GFP_KERNEL); \
770 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
771 struct module_kobject *mk, char *buffer) \
773 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
775 static int modinfo_##field##_exists(struct module *mod) \
777 return mod->field != NULL; \
779 static void free_modinfo_##field(struct module *mod) \
784 static struct module_attribute modinfo_##field = { \
785 .attr = { .name = __stringify(field), .mode = 0444 }, \
786 .show = show_modinfo_##field, \
787 .setup = setup_modinfo_##field, \
788 .test = modinfo_##field##_exists, \
789 .free = free_modinfo_##field, \
792 MODINFO_ATTR(version
);
793 MODINFO_ATTR(srcversion
);
795 static char last_unloaded_module
[MODULE_NAME_LEN
+1];
797 #ifdef CONFIG_MODULE_UNLOAD
799 EXPORT_TRACEPOINT_SYMBOL(module_get
);
801 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
802 #define MODULE_REF_BASE 1
804 /* Init the unload section of the module. */
805 static int module_unload_init(struct module
*mod
)
808 * Initialize reference counter to MODULE_REF_BASE.
809 * refcnt == 0 means module is going.
811 atomic_set(&mod
->refcnt
, MODULE_REF_BASE
);
813 INIT_LIST_HEAD(&mod
->source_list
);
814 INIT_LIST_HEAD(&mod
->target_list
);
816 /* Hold reference count during initialization. */
817 atomic_inc(&mod
->refcnt
);
822 /* Does a already use b? */
823 static int already_uses(struct module
*a
, struct module
*b
)
825 struct module_use
*use
;
827 list_for_each_entry(use
, &b
->source_list
, source_list
) {
828 if (use
->source
== a
) {
829 pr_debug("%s uses %s!\n", a
->name
, b
->name
);
833 pr_debug("%s does not use %s!\n", a
->name
, b
->name
);
839 * - we add 'a' as a "source", 'b' as a "target" of module use
840 * - the module_use is added to the list of 'b' sources (so
841 * 'b' can walk the list to see who sourced them), and of 'a'
842 * targets (so 'a' can see what modules it targets).
844 static int add_module_usage(struct module
*a
, struct module
*b
)
846 struct module_use
*use
;
848 pr_debug("Allocating new usage for %s.\n", a
->name
);
849 use
= kmalloc(sizeof(*use
), GFP_ATOMIC
);
855 list_add(&use
->source_list
, &b
->source_list
);
856 list_add(&use
->target_list
, &a
->target_list
);
860 /* Module a uses b: caller needs module_mutex() */
861 int ref_module(struct module
*a
, struct module
*b
)
865 if (b
== NULL
|| already_uses(a
, b
))
868 /* If module isn't available, we fail. */
869 err
= strong_try_module_get(b
);
873 err
= add_module_usage(a
, b
);
880 EXPORT_SYMBOL_GPL(ref_module
);
882 /* Clear the unload stuff of the module. */
883 static void module_unload_free(struct module
*mod
)
885 struct module_use
*use
, *tmp
;
887 mutex_lock(&module_mutex
);
888 list_for_each_entry_safe(use
, tmp
, &mod
->target_list
, target_list
) {
889 struct module
*i
= use
->target
;
890 pr_debug("%s unusing %s\n", mod
->name
, i
->name
);
892 list_del(&use
->source_list
);
893 list_del(&use
->target_list
);
896 mutex_unlock(&module_mutex
);
899 #ifdef CONFIG_MODULE_FORCE_UNLOAD
900 static inline int try_force_unload(unsigned int flags
)
902 int ret
= (flags
& O_TRUNC
);
904 add_taint(TAINT_FORCED_RMMOD
, LOCKDEP_NOW_UNRELIABLE
);
908 static inline int try_force_unload(unsigned int flags
)
912 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
914 /* Try to release refcount of module, 0 means success. */
915 static int try_release_module_ref(struct module
*mod
)
919 /* Try to decrement refcnt which we set at loading */
920 ret
= atomic_sub_return(MODULE_REF_BASE
, &mod
->refcnt
);
923 /* Someone can put this right now, recover with checking */
924 ret
= atomic_add_unless(&mod
->refcnt
, MODULE_REF_BASE
, 0);
929 static int try_stop_module(struct module
*mod
, int flags
, int *forced
)
931 /* If it's not unused, quit unless we're forcing. */
932 if (try_release_module_ref(mod
) != 0) {
933 *forced
= try_force_unload(flags
);
938 /* Mark it as dying. */
939 mod
->state
= MODULE_STATE_GOING
;
945 * module_refcount - return the refcount or -1 if unloading
947 * @mod: the module we're checking
950 * -1 if the module is in the process of unloading
951 * otherwise the number of references in the kernel to the module
953 int module_refcount(struct module
*mod
)
955 return atomic_read(&mod
->refcnt
) - MODULE_REF_BASE
;
957 EXPORT_SYMBOL(module_refcount
);
959 /* This exists whether we can unload or not */
960 static void free_module(struct module
*mod
);
962 SYSCALL_DEFINE2(delete_module
, const char __user
*, name_user
,
966 char name
[MODULE_NAME_LEN
];
969 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
972 if (strncpy_from_user(name
, name_user
, MODULE_NAME_LEN
-1) < 0)
974 name
[MODULE_NAME_LEN
-1] = '\0';
976 audit_log_kern_module(name
);
978 if (mutex_lock_interruptible(&module_mutex
) != 0)
981 mod
= find_module(name
);
987 if (!list_empty(&mod
->source_list
)) {
988 /* Other modules depend on us: get rid of them first. */
993 /* Doing init or already dying? */
994 if (mod
->state
!= MODULE_STATE_LIVE
) {
995 /* FIXME: if (force), slam module count damn the torpedoes */
996 pr_debug("%s already dying\n", mod
->name
);
1001 /* If it has an init func, it must have an exit func to unload */
1002 if (mod
->init
&& !mod
->exit
) {
1003 forced
= try_force_unload(flags
);
1005 /* This module can't be removed */
1011 /* Stop the machine so refcounts can't move and disable module. */
1012 ret
= try_stop_module(mod
, flags
, &forced
);
1016 mutex_unlock(&module_mutex
);
1017 /* Final destruction now no one is using it. */
1018 if (mod
->exit
!= NULL
)
1020 blocking_notifier_call_chain(&module_notify_list
,
1021 MODULE_STATE_GOING
, mod
);
1022 klp_module_going(mod
);
1023 ftrace_release_mod(mod
);
1025 async_synchronize_full();
1027 /* Store the name of the last unloaded module for diagnostic purposes */
1028 strlcpy(last_unloaded_module
, mod
->name
, sizeof(last_unloaded_module
));
1033 mutex_unlock(&module_mutex
);
1037 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1039 struct module_use
*use
;
1040 int printed_something
= 0;
1042 seq_printf(m
, " %i ", module_refcount(mod
));
1045 * Always include a trailing , so userspace can differentiate
1046 * between this and the old multi-field proc format.
1048 list_for_each_entry(use
, &mod
->source_list
, source_list
) {
1049 printed_something
= 1;
1050 seq_printf(m
, "%s,", use
->source
->name
);
1053 if (mod
->init
!= NULL
&& mod
->exit
== NULL
) {
1054 printed_something
= 1;
1055 seq_puts(m
, "[permanent],");
1058 if (!printed_something
)
1062 void __symbol_put(const char *symbol
)
1064 struct module
*owner
;
1067 if (!find_symbol(symbol
, &owner
, NULL
, true, false))
1072 EXPORT_SYMBOL(__symbol_put
);
1074 /* Note this assumes addr is a function, which it currently always is. */
1075 void symbol_put_addr(void *addr
)
1077 struct module
*modaddr
;
1078 unsigned long a
= (unsigned long)dereference_function_descriptor(addr
);
1080 if (core_kernel_text(a
))
1084 * Even though we hold a reference on the module; we still need to
1085 * disable preemption in order to safely traverse the data structure.
1088 modaddr
= __module_text_address(a
);
1090 module_put(modaddr
);
1093 EXPORT_SYMBOL_GPL(symbol_put_addr
);
1095 static ssize_t
show_refcnt(struct module_attribute
*mattr
,
1096 struct module_kobject
*mk
, char *buffer
)
1098 return sprintf(buffer
, "%i\n", module_refcount(mk
->mod
));
1101 static struct module_attribute modinfo_refcnt
=
1102 __ATTR(refcnt
, 0444, show_refcnt
, NULL
);
1104 void __module_get(struct module
*module
)
1108 atomic_inc(&module
->refcnt
);
1109 trace_module_get(module
, _RET_IP_
);
1113 EXPORT_SYMBOL(__module_get
);
1115 bool try_module_get(struct module
*module
)
1121 /* Note: here, we can fail to get a reference */
1122 if (likely(module_is_live(module
) &&
1123 atomic_inc_not_zero(&module
->refcnt
) != 0))
1124 trace_module_get(module
, _RET_IP_
);
1132 EXPORT_SYMBOL(try_module_get
);
1134 void module_put(struct module
*module
)
1140 ret
= atomic_dec_if_positive(&module
->refcnt
);
1141 WARN_ON(ret
< 0); /* Failed to put refcount */
1142 trace_module_put(module
, _RET_IP_
);
1146 EXPORT_SYMBOL(module_put
);
1148 #else /* !CONFIG_MODULE_UNLOAD */
1149 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1151 /* We don't know the usage count, or what modules are using. */
1152 seq_puts(m
, " - -");
1155 static inline void module_unload_free(struct module
*mod
)
1159 int ref_module(struct module
*a
, struct module
*b
)
1161 return strong_try_module_get(b
);
1163 EXPORT_SYMBOL_GPL(ref_module
);
1165 static inline int module_unload_init(struct module
*mod
)
1169 #endif /* CONFIG_MODULE_UNLOAD */
1171 static size_t module_flags_taint(struct module
*mod
, char *buf
)
1176 for (i
= 0; i
< TAINT_FLAGS_COUNT
; i
++) {
1177 if (taint_flags
[i
].module
&& test_bit(i
, &mod
->taints
))
1178 buf
[l
++] = taint_flags
[i
].c_true
;
1184 static ssize_t
show_initstate(struct module_attribute
*mattr
,
1185 struct module_kobject
*mk
, char *buffer
)
1187 const char *state
= "unknown";
1189 switch (mk
->mod
->state
) {
1190 case MODULE_STATE_LIVE
:
1193 case MODULE_STATE_COMING
:
1196 case MODULE_STATE_GOING
:
1202 return sprintf(buffer
, "%s\n", state
);
1205 static struct module_attribute modinfo_initstate
=
1206 __ATTR(initstate
, 0444, show_initstate
, NULL
);
1208 static ssize_t
store_uevent(struct module_attribute
*mattr
,
1209 struct module_kobject
*mk
,
1210 const char *buffer
, size_t count
)
1212 kobject_synth_uevent(&mk
->kobj
, buffer
, count
);
1216 struct module_attribute module_uevent
=
1217 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1219 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1220 struct module_kobject
*mk
, char *buffer
)
1222 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1225 static struct module_attribute modinfo_coresize
=
1226 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1228 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1229 struct module_kobject
*mk
, char *buffer
)
1231 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1234 static struct module_attribute modinfo_initsize
=
1235 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1237 static ssize_t
show_taint(struct module_attribute
*mattr
,
1238 struct module_kobject
*mk
, char *buffer
)
1242 l
= module_flags_taint(mk
->mod
, buffer
);
1247 static struct module_attribute modinfo_taint
=
1248 __ATTR(taint
, 0444, show_taint
, NULL
);
1250 static struct module_attribute
*modinfo_attrs
[] = {
1253 &modinfo_srcversion
,
1258 #ifdef CONFIG_MODULE_UNLOAD
1264 static const char vermagic
[] = VERMAGIC_STRING
;
1266 static int try_to_force_load(struct module
*mod
, const char *reason
)
1268 #ifdef CONFIG_MODULE_FORCE_LOAD
1269 if (!test_taint(TAINT_FORCED_MODULE
))
1270 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1271 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1278 #ifdef CONFIG_MODVERSIONS
1280 static u32
resolve_rel_crc(const s32
*crc
)
1282 return *(u32
*)((void *)crc
+ *crc
);
1285 static int check_version(const struct load_info
*info
,
1286 const char *symname
,
1290 Elf_Shdr
*sechdrs
= info
->sechdrs
;
1291 unsigned int versindex
= info
->index
.vers
;
1292 unsigned int i
, num_versions
;
1293 struct modversion_info
*versions
;
1295 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1299 /* No versions at all? modprobe --force does this. */
1301 return try_to_force_load(mod
, symname
) == 0;
1303 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1304 num_versions
= sechdrs
[versindex
].sh_size
1305 / sizeof(struct modversion_info
);
1307 for (i
= 0; i
< num_versions
; i
++) {
1310 if (strcmp(versions
[i
].name
, symname
) != 0)
1313 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS
))
1314 crcval
= resolve_rel_crc(crc
);
1317 if (versions
[i
].crc
== crcval
)
1319 pr_debug("Found checksum %X vs module %lX\n",
1320 crcval
, versions
[i
].crc
);
1324 /* Broken toolchain. Warn once, then let it go.. */
1325 pr_warn_once("%s: no symbol version for %s\n", info
->name
, symname
);
1329 pr_warn("%s: disagrees about version of symbol %s\n",
1330 info
->name
, symname
);
1334 static inline int check_modstruct_version(const struct load_info
*info
,
1340 * Since this should be found in kernel (which can't be removed), no
1341 * locking is necessary -- use preempt_disable() to placate lockdep.
1344 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout
), NULL
,
1345 &crc
, true, false)) {
1350 return check_version(info
, VMLINUX_SYMBOL_STR(module_layout
),
1354 /* First part is kernel version, which we ignore if module has crcs. */
1355 static inline int same_magic(const char *amagic
, const char *bmagic
,
1359 amagic
+= strcspn(amagic
, " ");
1360 bmagic
+= strcspn(bmagic
, " ");
1362 return strcmp(amagic
, bmagic
) == 0;
1365 static inline int check_version(const struct load_info
*info
,
1366 const char *symname
,
1373 static inline int check_modstruct_version(const struct load_info
*info
,
1379 static inline int same_magic(const char *amagic
, const char *bmagic
,
1382 return strcmp(amagic
, bmagic
) == 0;
1384 #endif /* CONFIG_MODVERSIONS */
1386 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1387 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1388 const struct load_info
*info
,
1392 struct module
*owner
;
1393 const struct kernel_symbol
*sym
;
1398 * The module_mutex should not be a heavily contended lock;
1399 * if we get the occasional sleep here, we'll go an extra iteration
1400 * in the wait_event_interruptible(), which is harmless.
1402 sched_annotate_sleep();
1403 mutex_lock(&module_mutex
);
1404 sym
= find_symbol(name
, &owner
, &crc
,
1405 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1409 if (!check_version(info
, name
, mod
, crc
)) {
1410 sym
= ERR_PTR(-EINVAL
);
1414 err
= ref_module(mod
, owner
);
1421 /* We must make copy under the lock if we failed to get ref. */
1422 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1424 mutex_unlock(&module_mutex
);
1428 static const struct kernel_symbol
*
1429 resolve_symbol_wait(struct module
*mod
,
1430 const struct load_info
*info
,
1433 const struct kernel_symbol
*ksym
;
1434 char owner
[MODULE_NAME_LEN
];
1436 if (wait_event_interruptible_timeout(module_wq
,
1437 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1438 || PTR_ERR(ksym
) != -EBUSY
,
1440 pr_warn("%s: gave up waiting for init of module %s.\n",
1447 * /sys/module/foo/sections stuff
1448 * J. Corbet <corbet@lwn.net>
1452 #ifdef CONFIG_KALLSYMS
1453 static inline bool sect_empty(const Elf_Shdr
*sect
)
1455 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1458 struct module_sect_attr
{
1459 struct module_attribute mattr
;
1461 unsigned long address
;
1464 struct module_sect_attrs
{
1465 struct attribute_group grp
;
1466 unsigned int nsections
;
1467 struct module_sect_attr attrs
[0];
1470 static ssize_t
module_sect_show(struct module_attribute
*mattr
,
1471 struct module_kobject
*mk
, char *buf
)
1473 struct module_sect_attr
*sattr
=
1474 container_of(mattr
, struct module_sect_attr
, mattr
);
1475 return sprintf(buf
, "0x%px\n", kptr_restrict
< 2 ?
1476 (void *)sattr
->address
: NULL
);
1479 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1481 unsigned int section
;
1483 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1484 kfree(sect_attrs
->attrs
[section
].name
);
1488 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1490 unsigned int nloaded
= 0, i
, size
[2];
1491 struct module_sect_attrs
*sect_attrs
;
1492 struct module_sect_attr
*sattr
;
1493 struct attribute
**gattr
;
1495 /* Count loaded sections and allocate structures */
1496 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1497 if (!sect_empty(&info
->sechdrs
[i
]))
1499 size
[0] = ALIGN(sizeof(*sect_attrs
)
1500 + nloaded
* sizeof(sect_attrs
->attrs
[0]),
1501 sizeof(sect_attrs
->grp
.attrs
[0]));
1502 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.attrs
[0]);
1503 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1504 if (sect_attrs
== NULL
)
1507 /* Setup section attributes. */
1508 sect_attrs
->grp
.name
= "sections";
1509 sect_attrs
->grp
.attrs
= (void *)sect_attrs
+ size
[0];
1511 sect_attrs
->nsections
= 0;
1512 sattr
= §_attrs
->attrs
[0];
1513 gattr
= §_attrs
->grp
.attrs
[0];
1514 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1515 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1516 if (sect_empty(sec
))
1518 sattr
->address
= sec
->sh_addr
;
1519 sattr
->name
= kstrdup(info
->secstrings
+ sec
->sh_name
,
1521 if (sattr
->name
== NULL
)
1523 sect_attrs
->nsections
++;
1524 sysfs_attr_init(&sattr
->mattr
.attr
);
1525 sattr
->mattr
.show
= module_sect_show
;
1526 sattr
->mattr
.store
= NULL
;
1527 sattr
->mattr
.attr
.name
= sattr
->name
;
1528 sattr
->mattr
.attr
.mode
= S_IRUSR
;
1529 *(gattr
++) = &(sattr
++)->mattr
.attr
;
1533 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1536 mod
->sect_attrs
= sect_attrs
;
1539 free_sect_attrs(sect_attrs
);
1542 static void remove_sect_attrs(struct module
*mod
)
1544 if (mod
->sect_attrs
) {
1545 sysfs_remove_group(&mod
->mkobj
.kobj
,
1546 &mod
->sect_attrs
->grp
);
1547 /* We are positive that no one is using any sect attrs
1548 * at this point. Deallocate immediately. */
1549 free_sect_attrs(mod
->sect_attrs
);
1550 mod
->sect_attrs
= NULL
;
1555 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1558 struct module_notes_attrs
{
1559 struct kobject
*dir
;
1561 struct bin_attribute attrs
[0];
1564 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1565 struct bin_attribute
*bin_attr
,
1566 char *buf
, loff_t pos
, size_t count
)
1569 * The caller checked the pos and count against our size.
1571 memcpy(buf
, bin_attr
->private + pos
, count
);
1575 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1578 if (notes_attrs
->dir
) {
1580 sysfs_remove_bin_file(notes_attrs
->dir
,
1581 ¬es_attrs
->attrs
[i
]);
1582 kobject_put(notes_attrs
->dir
);
1587 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1589 unsigned int notes
, loaded
, i
;
1590 struct module_notes_attrs
*notes_attrs
;
1591 struct bin_attribute
*nattr
;
1593 /* failed to create section attributes, so can't create notes */
1594 if (!mod
->sect_attrs
)
1597 /* Count notes sections and allocate structures. */
1599 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1600 if (!sect_empty(&info
->sechdrs
[i
]) &&
1601 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1607 notes_attrs
= kzalloc(sizeof(*notes_attrs
)
1608 + notes
* sizeof(notes_attrs
->attrs
[0]),
1610 if (notes_attrs
== NULL
)
1613 notes_attrs
->notes
= notes
;
1614 nattr
= ¬es_attrs
->attrs
[0];
1615 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1616 if (sect_empty(&info
->sechdrs
[i
]))
1618 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1619 sysfs_bin_attr_init(nattr
);
1620 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].name
;
1621 nattr
->attr
.mode
= S_IRUGO
;
1622 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1623 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1624 nattr
->read
= module_notes_read
;
1630 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1631 if (!notes_attrs
->dir
)
1634 for (i
= 0; i
< notes
; ++i
)
1635 if (sysfs_create_bin_file(notes_attrs
->dir
,
1636 ¬es_attrs
->attrs
[i
]))
1639 mod
->notes_attrs
= notes_attrs
;
1643 free_notes_attrs(notes_attrs
, i
);
1646 static void remove_notes_attrs(struct module
*mod
)
1648 if (mod
->notes_attrs
)
1649 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1654 static inline void add_sect_attrs(struct module
*mod
,
1655 const struct load_info
*info
)
1659 static inline void remove_sect_attrs(struct module
*mod
)
1663 static inline void add_notes_attrs(struct module
*mod
,
1664 const struct load_info
*info
)
1668 static inline void remove_notes_attrs(struct module
*mod
)
1671 #endif /* CONFIG_KALLSYMS */
1673 static void del_usage_links(struct module
*mod
)
1675 #ifdef CONFIG_MODULE_UNLOAD
1676 struct module_use
*use
;
1678 mutex_lock(&module_mutex
);
1679 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1680 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1681 mutex_unlock(&module_mutex
);
1685 static int add_usage_links(struct module
*mod
)
1688 #ifdef CONFIG_MODULE_UNLOAD
1689 struct module_use
*use
;
1691 mutex_lock(&module_mutex
);
1692 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1693 ret
= sysfs_create_link(use
->target
->holders_dir
,
1694 &mod
->mkobj
.kobj
, mod
->name
);
1698 mutex_unlock(&module_mutex
);
1700 del_usage_links(mod
);
1705 static int module_add_modinfo_attrs(struct module
*mod
)
1707 struct module_attribute
*attr
;
1708 struct module_attribute
*temp_attr
;
1712 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1713 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1715 if (!mod
->modinfo_attrs
)
1718 temp_attr
= mod
->modinfo_attrs
;
1719 for (i
= 0; (attr
= modinfo_attrs
[i
]) && !error
; i
++) {
1720 if (!attr
->test
|| attr
->test(mod
)) {
1721 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1722 sysfs_attr_init(&temp_attr
->attr
);
1723 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1731 static void module_remove_modinfo_attrs(struct module
*mod
)
1733 struct module_attribute
*attr
;
1736 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1737 /* pick a field to test for end of list */
1738 if (!attr
->attr
.name
)
1740 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1744 kfree(mod
->modinfo_attrs
);
1747 static void mod_kobject_put(struct module
*mod
)
1749 DECLARE_COMPLETION_ONSTACK(c
);
1750 mod
->mkobj
.kobj_completion
= &c
;
1751 kobject_put(&mod
->mkobj
.kobj
);
1752 wait_for_completion(&c
);
1755 static int mod_sysfs_init(struct module
*mod
)
1758 struct kobject
*kobj
;
1760 if (!module_sysfs_initialized
) {
1761 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1766 kobj
= kset_find_obj(module_kset
, mod
->name
);
1768 pr_err("%s: module is already loaded\n", mod
->name
);
1774 mod
->mkobj
.mod
= mod
;
1776 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1777 mod
->mkobj
.kobj
.kset
= module_kset
;
1778 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1781 mod_kobject_put(mod
);
1783 /* delay uevent until full sysfs population */
1788 static int mod_sysfs_setup(struct module
*mod
,
1789 const struct load_info
*info
,
1790 struct kernel_param
*kparam
,
1791 unsigned int num_params
)
1795 err
= mod_sysfs_init(mod
);
1799 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1800 if (!mod
->holders_dir
) {
1805 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1807 goto out_unreg_holders
;
1809 err
= module_add_modinfo_attrs(mod
);
1811 goto out_unreg_param
;
1813 err
= add_usage_links(mod
);
1815 goto out_unreg_modinfo_attrs
;
1817 add_sect_attrs(mod
, info
);
1818 add_notes_attrs(mod
, info
);
1820 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1823 out_unreg_modinfo_attrs
:
1824 module_remove_modinfo_attrs(mod
);
1826 module_param_sysfs_remove(mod
);
1828 kobject_put(mod
->holders_dir
);
1830 mod_kobject_put(mod
);
1835 static void mod_sysfs_fini(struct module
*mod
)
1837 remove_notes_attrs(mod
);
1838 remove_sect_attrs(mod
);
1839 mod_kobject_put(mod
);
1842 static void init_param_lock(struct module
*mod
)
1844 mutex_init(&mod
->param_lock
);
1846 #else /* !CONFIG_SYSFS */
1848 static int mod_sysfs_setup(struct module
*mod
,
1849 const struct load_info
*info
,
1850 struct kernel_param
*kparam
,
1851 unsigned int num_params
)
1856 static void mod_sysfs_fini(struct module
*mod
)
1860 static void module_remove_modinfo_attrs(struct module
*mod
)
1864 static void del_usage_links(struct module
*mod
)
1868 static void init_param_lock(struct module
*mod
)
1871 #endif /* CONFIG_SYSFS */
1873 static void mod_sysfs_teardown(struct module
*mod
)
1875 del_usage_links(mod
);
1876 module_remove_modinfo_attrs(mod
);
1877 module_param_sysfs_remove(mod
);
1878 kobject_put(mod
->mkobj
.drivers_dir
);
1879 kobject_put(mod
->holders_dir
);
1880 mod_sysfs_fini(mod
);
1883 #ifdef CONFIG_STRICT_MODULE_RWX
1885 * LKM RO/NX protection: protect module's text/ro-data
1886 * from modification and any data from execution.
1888 * General layout of module is:
1889 * [text] [read-only-data] [ro-after-init] [writable data]
1890 * text_size -----^ ^ ^ ^
1891 * ro_size ------------------------| | |
1892 * ro_after_init_size -----------------------------| |
1893 * size -----------------------------------------------------------|
1895 * These values are always page-aligned (as is base)
1897 static void frob_text(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 set_memory((unsigned long)layout
->base
,
1903 layout
->text_size
>> PAGE_SHIFT
);
1906 static void frob_rodata(const struct module_layout
*layout
,
1907 int (*set_memory
)(unsigned long start
, int num_pages
))
1909 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1910 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1911 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1912 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
1913 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
1916 static void frob_ro_after_init(const struct module_layout
*layout
,
1917 int (*set_memory
)(unsigned long start
, int num_pages
))
1919 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1920 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1921 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1922 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
1923 (layout
->ro_after_init_size
- layout
->ro_size
) >> PAGE_SHIFT
);
1926 static void frob_writable_data(const struct module_layout
*layout
,
1927 int (*set_memory
)(unsigned long start
, int num_pages
))
1929 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1930 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1931 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
1932 set_memory((unsigned long)layout
->base
+ layout
->ro_after_init_size
,
1933 (layout
->size
- layout
->ro_after_init_size
) >> PAGE_SHIFT
);
1936 /* livepatching wants to disable read-only so it can frob module. */
1937 void module_disable_ro(const struct module
*mod
)
1939 if (!rodata_enabled
)
1942 frob_text(&mod
->core_layout
, set_memory_rw
);
1943 frob_rodata(&mod
->core_layout
, set_memory_rw
);
1944 frob_ro_after_init(&mod
->core_layout
, set_memory_rw
);
1945 frob_text(&mod
->init_layout
, set_memory_rw
);
1946 frob_rodata(&mod
->init_layout
, set_memory_rw
);
1949 void module_enable_ro(const struct module
*mod
, bool after_init
)
1951 if (!rodata_enabled
)
1954 frob_text(&mod
->core_layout
, set_memory_ro
);
1955 frob_rodata(&mod
->core_layout
, set_memory_ro
);
1956 frob_text(&mod
->init_layout
, set_memory_ro
);
1957 frob_rodata(&mod
->init_layout
, set_memory_ro
);
1960 frob_ro_after_init(&mod
->core_layout
, set_memory_ro
);
1963 static void module_enable_nx(const struct module
*mod
)
1965 frob_rodata(&mod
->core_layout
, set_memory_nx
);
1966 frob_ro_after_init(&mod
->core_layout
, set_memory_nx
);
1967 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
1968 frob_rodata(&mod
->init_layout
, set_memory_nx
);
1969 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
1972 static void module_disable_nx(const struct module
*mod
)
1974 frob_rodata(&mod
->core_layout
, set_memory_x
);
1975 frob_ro_after_init(&mod
->core_layout
, set_memory_x
);
1976 frob_writable_data(&mod
->core_layout
, set_memory_x
);
1977 frob_rodata(&mod
->init_layout
, set_memory_x
);
1978 frob_writable_data(&mod
->init_layout
, set_memory_x
);
1981 /* Iterate through all modules and set each module's text as RW */
1982 void set_all_modules_text_rw(void)
1986 if (!rodata_enabled
)
1989 mutex_lock(&module_mutex
);
1990 list_for_each_entry_rcu(mod
, &modules
, list
) {
1991 if (mod
->state
== MODULE_STATE_UNFORMED
)
1994 frob_text(&mod
->core_layout
, set_memory_rw
);
1995 frob_text(&mod
->init_layout
, set_memory_rw
);
1997 mutex_unlock(&module_mutex
);
2000 /* Iterate through all modules and set each module's text as RO */
2001 void set_all_modules_text_ro(void)
2005 if (!rodata_enabled
)
2008 mutex_lock(&module_mutex
);
2009 list_for_each_entry_rcu(mod
, &modules
, list
) {
2011 * Ignore going modules since it's possible that ro
2012 * protection has already been disabled, otherwise we'll
2013 * run into protection faults at module deallocation.
2015 if (mod
->state
== MODULE_STATE_UNFORMED
||
2016 mod
->state
== MODULE_STATE_GOING
)
2019 frob_text(&mod
->core_layout
, set_memory_ro
);
2020 frob_text(&mod
->init_layout
, set_memory_ro
);
2022 mutex_unlock(&module_mutex
);
2025 static void disable_ro_nx(const struct module_layout
*layout
)
2027 if (rodata_enabled
) {
2028 frob_text(layout
, set_memory_rw
);
2029 frob_rodata(layout
, set_memory_rw
);
2030 frob_ro_after_init(layout
, set_memory_rw
);
2032 frob_rodata(layout
, set_memory_x
);
2033 frob_ro_after_init(layout
, set_memory_x
);
2034 frob_writable_data(layout
, set_memory_x
);
2038 static void disable_ro_nx(const struct module_layout
*layout
) { }
2039 static void module_enable_nx(const struct module
*mod
) { }
2040 static void module_disable_nx(const struct module
*mod
) { }
2043 #ifdef CONFIG_LIVEPATCH
2045 * Persist Elf information about a module. Copy the Elf header,
2046 * section header table, section string table, and symtab section
2047 * index from info to mod->klp_info.
2049 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2051 unsigned int size
, symndx
;
2054 size
= sizeof(*mod
->klp_info
);
2055 mod
->klp_info
= kmalloc(size
, GFP_KERNEL
);
2056 if (mod
->klp_info
== NULL
)
2060 size
= sizeof(mod
->klp_info
->hdr
);
2061 memcpy(&mod
->klp_info
->hdr
, info
->hdr
, size
);
2063 /* Elf section header table */
2064 size
= sizeof(*info
->sechdrs
) * info
->hdr
->e_shnum
;
2065 mod
->klp_info
->sechdrs
= kmalloc(size
, GFP_KERNEL
);
2066 if (mod
->klp_info
->sechdrs
== NULL
) {
2070 memcpy(mod
->klp_info
->sechdrs
, info
->sechdrs
, size
);
2072 /* Elf section name string table */
2073 size
= info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_size
;
2074 mod
->klp_info
->secstrings
= kmalloc(size
, GFP_KERNEL
);
2075 if (mod
->klp_info
->secstrings
== NULL
) {
2079 memcpy(mod
->klp_info
->secstrings
, info
->secstrings
, size
);
2081 /* Elf symbol section index */
2082 symndx
= info
->index
.sym
;
2083 mod
->klp_info
->symndx
= symndx
;
2086 * For livepatch modules, core_kallsyms.symtab is a complete
2087 * copy of the original symbol table. Adjust sh_addr to point
2088 * to core_kallsyms.symtab since the copy of the symtab in module
2089 * init memory is freed at the end of do_init_module().
2091 mod
->klp_info
->sechdrs
[symndx
].sh_addr
= \
2092 (unsigned long) mod
->core_kallsyms
.symtab
;
2097 kfree(mod
->klp_info
->sechdrs
);
2099 kfree(mod
->klp_info
);
2103 static void free_module_elf(struct module
*mod
)
2105 kfree(mod
->klp_info
->sechdrs
);
2106 kfree(mod
->klp_info
->secstrings
);
2107 kfree(mod
->klp_info
);
2109 #else /* !CONFIG_LIVEPATCH */
2110 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2115 static void free_module_elf(struct module
*mod
)
2118 #endif /* CONFIG_LIVEPATCH */
2120 void __weak
module_memfree(void *module_region
)
2122 vfree(module_region
);
2125 void __weak
module_arch_cleanup(struct module
*mod
)
2129 void __weak
module_arch_freeing_init(struct module
*mod
)
2133 /* Free a module, remove from lists, etc. */
2134 static void free_module(struct module
*mod
)
2136 trace_module_free(mod
);
2138 mod_sysfs_teardown(mod
);
2140 /* We leave it in list to prevent duplicate loads, but make sure
2141 * that noone uses it while it's being deconstructed. */
2142 mutex_lock(&module_mutex
);
2143 mod
->state
= MODULE_STATE_UNFORMED
;
2144 mutex_unlock(&module_mutex
);
2146 /* Remove dynamic debug info */
2147 ddebug_remove_module(mod
->name
);
2149 /* Arch-specific cleanup. */
2150 module_arch_cleanup(mod
);
2152 /* Module unload stuff */
2153 module_unload_free(mod
);
2155 /* Free any allocated parameters. */
2156 destroy_params(mod
->kp
, mod
->num_kp
);
2158 if (is_livepatch_module(mod
))
2159 free_module_elf(mod
);
2161 /* Now we can delete it from the lists */
2162 mutex_lock(&module_mutex
);
2163 /* Unlink carefully: kallsyms could be walking list. */
2164 list_del_rcu(&mod
->list
);
2165 mod_tree_remove(mod
);
2166 /* Remove this module from bug list, this uses list_del_rcu */
2167 module_bug_cleanup(mod
);
2168 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2169 synchronize_sched();
2170 mutex_unlock(&module_mutex
);
2172 /* This may be empty, but that's OK */
2173 disable_ro_nx(&mod
->init_layout
);
2174 module_arch_freeing_init(mod
);
2175 module_memfree(mod
->init_layout
.base
);
2177 percpu_modfree(mod
);
2179 /* Free lock-classes; relies on the preceding sync_rcu(). */
2180 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2182 /* Finally, free the core (containing the module structure) */
2183 disable_ro_nx(&mod
->core_layout
);
2184 module_memfree(mod
->core_layout
.base
);
2187 update_protections(current
->mm
);
2191 void *__symbol_get(const char *symbol
)
2193 struct module
*owner
;
2194 const struct kernel_symbol
*sym
;
2197 sym
= find_symbol(symbol
, &owner
, NULL
, true, true);
2198 if (sym
&& strong_try_module_get(owner
))
2202 return sym
? (void *)sym
->value
: NULL
;
2204 EXPORT_SYMBOL_GPL(__symbol_get
);
2207 * Ensure that an exported symbol [global namespace] does not already exist
2208 * in the kernel or in some other module's exported symbol table.
2210 * You must hold the module_mutex.
2212 static int verify_export_symbols(struct module
*mod
)
2215 struct module
*owner
;
2216 const struct kernel_symbol
*s
;
2218 const struct kernel_symbol
*sym
;
2221 { mod
->syms
, mod
->num_syms
},
2222 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2223 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2224 #ifdef CONFIG_UNUSED_SYMBOLS
2225 { mod
->unused_syms
, mod
->num_unused_syms
},
2226 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2230 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2231 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2232 if (find_symbol(s
->name
, &owner
, NULL
, true, false)) {
2233 pr_err("%s: exports duplicate symbol %s"
2235 mod
->name
, s
->name
, module_name(owner
));
2243 /* Change all symbols so that st_value encodes the pointer directly. */
2244 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2246 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2247 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2248 unsigned long secbase
;
2251 const struct kernel_symbol
*ksym
;
2253 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2254 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2256 switch (sym
[i
].st_shndx
) {
2258 /* Ignore common symbols */
2259 if (!strncmp(name
, "__gnu_lto", 9))
2262 /* We compiled with -fno-common. These are not
2263 supposed to happen. */
2264 pr_debug("Common symbol: %s\n", name
);
2265 pr_warn("%s: please compile with -fno-common\n",
2271 /* Don't need to do anything */
2272 pr_debug("Absolute symbol: 0x%08lx\n",
2273 (long)sym
[i
].st_value
);
2277 /* Livepatch symbols are resolved by livepatch */
2281 ksym
= resolve_symbol_wait(mod
, info
, name
);
2282 /* Ok if resolved. */
2283 if (ksym
&& !IS_ERR(ksym
)) {
2284 sym
[i
].st_value
= ksym
->value
;
2289 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2292 pr_warn("%s: Unknown symbol %s (err %li)\n",
2293 mod
->name
, name
, PTR_ERR(ksym
));
2294 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2298 /* Divert to percpu allocation if a percpu var. */
2299 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2300 secbase
= (unsigned long)mod_percpu(mod
);
2302 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2303 sym
[i
].st_value
+= secbase
;
2311 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2316 /* Now do relocations. */
2317 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2318 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2320 /* Not a valid relocation section? */
2321 if (infosec
>= info
->hdr
->e_shnum
)
2324 /* Don't bother with non-allocated sections */
2325 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2328 /* Livepatch relocation sections are applied by livepatch */
2329 if (info
->sechdrs
[i
].sh_flags
& SHF_RELA_LIVEPATCH
)
2332 if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2333 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2334 info
->index
.sym
, i
, mod
);
2335 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2336 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2337 info
->index
.sym
, i
, mod
);
2344 /* Additional bytes needed by arch in front of individual sections */
2345 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2346 unsigned int section
)
2348 /* default implementation just returns zero */
2352 /* Update size with this section: return offset. */
2353 static long get_offset(struct module
*mod
, unsigned int *size
,
2354 Elf_Shdr
*sechdr
, unsigned int section
)
2358 *size
+= arch_mod_section_prepend(mod
, section
);
2359 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2360 *size
= ret
+ sechdr
->sh_size
;
2364 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2365 might -- code, read-only data, read-write data, small data. Tally
2366 sizes, and place the offsets into sh_entsize fields: high bit means it
2368 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2370 static unsigned long const masks
[][2] = {
2371 /* NOTE: all executable code must be the first section
2372 * in this array; otherwise modify the text_size
2373 * finder in the two loops below */
2374 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2375 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2376 { SHF_RO_AFTER_INIT
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2377 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2378 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2382 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2383 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2385 pr_debug("Core section allocation order:\n");
2386 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2387 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2388 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2389 const char *sname
= info
->secstrings
+ s
->sh_name
;
2391 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2392 || (s
->sh_flags
& masks
[m
][1])
2393 || s
->sh_entsize
!= ~0UL
2394 || strstarts(sname
, ".init"))
2396 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2397 pr_debug("\t%s\n", sname
);
2400 case 0: /* executable */
2401 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2402 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2404 case 1: /* RO: text and ro-data */
2405 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2406 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2408 case 2: /* RO after init */
2409 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2410 mod
->core_layout
.ro_after_init_size
= mod
->core_layout
.size
;
2412 case 4: /* whole core */
2413 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2418 pr_debug("Init section allocation order:\n");
2419 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2420 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2421 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2422 const char *sname
= info
->secstrings
+ s
->sh_name
;
2424 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2425 || (s
->sh_flags
& masks
[m
][1])
2426 || s
->sh_entsize
!= ~0UL
2427 || !strstarts(sname
, ".init"))
2429 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2430 | INIT_OFFSET_MASK
);
2431 pr_debug("\t%s\n", sname
);
2434 case 0: /* executable */
2435 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2436 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2438 case 1: /* RO: text and ro-data */
2439 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2440 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2444 * RO after init doesn't apply to init_layout (only
2445 * core_layout), so it just takes the value of ro_size.
2447 mod
->init_layout
.ro_after_init_size
= mod
->init_layout
.ro_size
;
2449 case 4: /* whole init */
2450 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2456 static void set_license(struct module
*mod
, const char *license
)
2459 license
= "unspecified";
2461 if (!license_is_gpl_compatible(license
)) {
2462 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2463 pr_warn("%s: module license '%s' taints kernel.\n",
2464 mod
->name
, license
);
2465 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2466 LOCKDEP_NOW_UNRELIABLE
);
2470 /* Parse tag=value strings from .modinfo section */
2471 static char *next_string(char *string
, unsigned long *secsize
)
2473 /* Skip non-zero chars */
2476 if ((*secsize
)-- <= 1)
2480 /* Skip any zero padding. */
2481 while (!string
[0]) {
2483 if ((*secsize
)-- <= 1)
2489 static char *get_modinfo(struct load_info
*info
, const char *tag
)
2492 unsigned int taglen
= strlen(tag
);
2493 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2494 unsigned long size
= infosec
->sh_size
;
2496 for (p
= (char *)infosec
->sh_addr
; p
; p
= next_string(p
, &size
)) {
2497 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2498 return p
+ taglen
+ 1;
2503 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2505 struct module_attribute
*attr
;
2508 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2510 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2514 static void free_modinfo(struct module
*mod
)
2516 struct module_attribute
*attr
;
2519 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2525 #ifdef CONFIG_KALLSYMS
2527 /* lookup symbol in given range of kernel_symbols */
2528 static const struct kernel_symbol
*lookup_symbol(const char *name
,
2529 const struct kernel_symbol
*start
,
2530 const struct kernel_symbol
*stop
)
2532 return bsearch(name
, start
, stop
- start
,
2533 sizeof(struct kernel_symbol
), cmp_name
);
2536 static int is_exported(const char *name
, unsigned long value
,
2537 const struct module
*mod
)
2539 const struct kernel_symbol
*ks
;
2541 ks
= lookup_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2543 ks
= lookup_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2544 return ks
!= NULL
&& ks
->value
== value
;
2548 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2550 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2552 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2553 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2558 if (sym
->st_shndx
== SHN_UNDEF
)
2560 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2562 if (sym
->st_shndx
>= SHN_LORESERVE
)
2564 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2566 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2567 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2568 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2570 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2575 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2576 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2581 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2588 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2589 unsigned int shnum
, unsigned int pcpundx
)
2591 const Elf_Shdr
*sec
;
2593 if (src
->st_shndx
== SHN_UNDEF
2594 || src
->st_shndx
>= shnum
2598 #ifdef CONFIG_KALLSYMS_ALL
2599 if (src
->st_shndx
== pcpundx
)
2603 sec
= sechdrs
+ src
->st_shndx
;
2604 if (!(sec
->sh_flags
& SHF_ALLOC
)
2605 #ifndef CONFIG_KALLSYMS_ALL
2606 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2608 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2615 * We only allocate and copy the strings needed by the parts of symtab
2616 * we keep. This is simple, but has the effect of making multiple
2617 * copies of duplicates. We could be more sophisticated, see
2618 * linux-kernel thread starting with
2619 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2621 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2623 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2624 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2626 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2628 /* Put symbol section at end of init part of module. */
2629 symsect
->sh_flags
|= SHF_ALLOC
;
2630 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2631 info
->index
.sym
) | INIT_OFFSET_MASK
;
2632 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2634 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2635 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2637 /* Compute total space required for the core symbols' strtab. */
2638 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2639 if (i
== 0 || is_livepatch_module(mod
) ||
2640 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2641 info
->index
.pcpu
)) {
2642 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2647 /* Append room for core symbols at end of core part. */
2648 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2649 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2650 mod
->core_layout
.size
+= strtab_size
;
2651 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2653 /* Put string table section at end of init part of module. */
2654 strsect
->sh_flags
|= SHF_ALLOC
;
2655 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2656 info
->index
.str
) | INIT_OFFSET_MASK
;
2657 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2659 /* We'll tack temporary mod_kallsyms on the end. */
2660 mod
->init_layout
.size
= ALIGN(mod
->init_layout
.size
,
2661 __alignof__(struct mod_kallsyms
));
2662 info
->mod_kallsyms_init_off
= mod
->init_layout
.size
;
2663 mod
->init_layout
.size
+= sizeof(struct mod_kallsyms
);
2664 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2668 * We use the full symtab and strtab which layout_symtab arranged to
2669 * be appended to the init section. Later we switch to the cut-down
2672 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2674 unsigned int i
, ndst
;
2678 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2680 /* Set up to point into init section. */
2681 mod
->kallsyms
= mod
->init_layout
.base
+ info
->mod_kallsyms_init_off
;
2683 mod
->kallsyms
->symtab
= (void *)symsec
->sh_addr
;
2684 mod
->kallsyms
->num_symtab
= symsec
->sh_size
/ sizeof(Elf_Sym
);
2685 /* Make sure we get permanent strtab: don't use info->strtab. */
2686 mod
->kallsyms
->strtab
= (void *)info
->sechdrs
[info
->index
.str
].sh_addr
;
2688 /* Set types up while we still have access to sections. */
2689 for (i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++)
2690 mod
->kallsyms
->symtab
[i
].st_info
2691 = elf_type(&mod
->kallsyms
->symtab
[i
], info
);
2693 /* Now populate the cut down core kallsyms for after init. */
2694 mod
->core_kallsyms
.symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2695 mod
->core_kallsyms
.strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2696 src
= mod
->kallsyms
->symtab
;
2697 for (ndst
= i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++) {
2698 if (i
== 0 || is_livepatch_module(mod
) ||
2699 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2700 info
->index
.pcpu
)) {
2702 dst
[ndst
++].st_name
= s
- mod
->core_kallsyms
.strtab
;
2703 s
+= strlcpy(s
, &mod
->kallsyms
->strtab
[src
[i
].st_name
],
2707 mod
->core_kallsyms
.num_symtab
= ndst
;
2710 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2714 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2717 #endif /* CONFIG_KALLSYMS */
2719 static void dynamic_debug_setup(struct module
*mod
, struct _ddebug
*debug
, unsigned int num
)
2723 #ifdef CONFIG_DYNAMIC_DEBUG
2724 if (ddebug_add_module(debug
, num
, mod
->name
))
2725 pr_err("dynamic debug error adding module: %s\n",
2730 static void dynamic_debug_remove(struct module
*mod
, struct _ddebug
*debug
)
2733 ddebug_remove_module(mod
->name
);
2736 void * __weak
module_alloc(unsigned long size
)
2738 return vmalloc_exec(size
);
2741 #ifdef CONFIG_DEBUG_KMEMLEAK
2742 static void kmemleak_load_module(const struct module
*mod
,
2743 const struct load_info
*info
)
2747 /* only scan the sections containing data */
2748 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2750 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2751 /* Scan all writable sections that's not executable */
2752 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2753 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2754 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2757 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2758 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2762 static inline void kmemleak_load_module(const struct module
*mod
,
2763 const struct load_info
*info
)
2768 #ifdef CONFIG_MODULE_SIG
2769 static int module_sig_check(struct load_info
*info
, int flags
)
2772 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2773 const void *mod
= info
->hdr
;
2776 * Require flags == 0, as a module with version information
2777 * removed is no longer the module that was signed
2780 info
->len
> markerlen
&&
2781 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2782 /* We truncate the module to discard the signature */
2783 info
->len
-= markerlen
;
2784 err
= mod_verify_sig(mod
, &info
->len
);
2788 info
->sig_ok
= true;
2792 /* Not having a signature is only an error if we're strict. */
2793 if (err
== -ENOKEY
&& !sig_enforce
&&
2794 !kernel_is_locked_down("Loading of unsigned modules"))
2799 #else /* !CONFIG_MODULE_SIG */
2800 static int module_sig_check(struct load_info
*info
, int flags
)
2804 #endif /* !CONFIG_MODULE_SIG */
2806 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2807 static int elf_header_check(struct load_info
*info
)
2809 if (info
->len
< sizeof(*(info
->hdr
)))
2812 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2813 || info
->hdr
->e_type
!= ET_REL
2814 || !elf_check_arch(info
->hdr
)
2815 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2818 if (info
->hdr
->e_shoff
>= info
->len
2819 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2820 info
->len
- info
->hdr
->e_shoff
))
2826 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2828 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2831 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2833 if (copy_from_user(dst
, usrc
, n
) != 0)
2843 #ifdef CONFIG_LIVEPATCH
2844 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2846 if (get_modinfo(info
, "livepatch")) {
2848 add_taint_module(mod
, TAINT_LIVEPATCH
, LOCKDEP_STILL_OK
);
2849 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2855 #else /* !CONFIG_LIVEPATCH */
2856 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2858 if (get_modinfo(info
, "livepatch")) {
2859 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2866 #endif /* CONFIG_LIVEPATCH */
2868 static void check_modinfo_retpoline(struct module
*mod
, struct load_info
*info
)
2870 if (retpoline_module_ok(get_modinfo(info
, "retpoline")))
2873 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
2877 /* Sets info->hdr and info->len. */
2878 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
2879 struct load_info
*info
)
2884 if (info
->len
< sizeof(*(info
->hdr
)))
2887 err
= security_kernel_read_file(NULL
, READING_MODULE
);
2891 /* Suck in entire file: we'll want most of it. */
2892 info
->hdr
= __vmalloc(info
->len
,
2893 GFP_KERNEL
| __GFP_NOWARN
, PAGE_KERNEL
);
2897 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
2905 static void free_copy(struct load_info
*info
)
2910 static int rewrite_section_headers(struct load_info
*info
, int flags
)
2914 /* This should always be true, but let's be sure. */
2915 info
->sechdrs
[0].sh_addr
= 0;
2917 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2918 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
2919 if (shdr
->sh_type
!= SHT_NOBITS
2920 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
2921 pr_err("Module len %lu truncated\n", info
->len
);
2925 /* Mark all sections sh_addr with their address in the
2927 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
2929 #ifndef CONFIG_MODULE_UNLOAD
2930 /* Don't load .exit sections */
2931 if (strstarts(info
->secstrings
+shdr
->sh_name
, ".exit"))
2932 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2936 /* Track but don't keep modinfo and version sections. */
2937 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
2938 info
->index
.vers
= 0; /* Pretend no __versions section! */
2940 info
->index
.vers
= find_sec(info
, "__versions");
2941 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2943 info
->index
.info
= find_sec(info
, ".modinfo");
2944 if (!info
->index
.info
)
2945 info
->name
= "(missing .modinfo section)";
2947 info
->name
= get_modinfo(info
, "name");
2948 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2954 * Set up our basic convenience variables (pointers to section headers,
2955 * search for module section index etc), and do some basic section
2958 * Return the temporary module pointer (we'll replace it with the final
2959 * one when we move the module sections around).
2961 static struct module
*setup_load_info(struct load_info
*info
, int flags
)
2967 /* Set up the convenience variables */
2968 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
2969 info
->secstrings
= (void *)info
->hdr
2970 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
2972 err
= rewrite_section_headers(info
, flags
);
2974 return ERR_PTR(err
);
2976 /* Find internal symbols and strings. */
2977 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2978 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
2979 info
->index
.sym
= i
;
2980 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
2981 info
->strtab
= (char *)info
->hdr
2982 + info
->sechdrs
[info
->index
.str
].sh_offset
;
2987 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
2988 if (!info
->index
.mod
) {
2989 pr_warn("%s: No module found in object\n",
2990 info
->name
?: "(missing .modinfo name field)");
2991 return ERR_PTR(-ENOEXEC
);
2993 /* This is temporary: point mod into copy of data. */
2994 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
2997 * If we didn't load the .modinfo 'name' field, fall back to
2998 * on-disk struct mod 'name' field.
3001 info
->name
= mod
->name
;
3003 if (info
->index
.sym
== 0) {
3004 pr_warn("%s: module has no symbols (stripped?)\n", info
->name
);
3005 return ERR_PTR(-ENOEXEC
);
3008 info
->index
.pcpu
= find_pcpusec(info
);
3010 /* Check module struct version now, before we try to use module. */
3011 if (!check_modstruct_version(info
, mod
))
3012 return ERR_PTR(-ENOEXEC
);
3017 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
3019 const char *modmagic
= get_modinfo(info
, "vermagic");
3022 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
3025 /* This is allowed: modprobe --force will invalidate it. */
3027 err
= try_to_force_load(mod
, "bad vermagic");
3030 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
3031 pr_err("%s: version magic '%s' should be '%s'\n",
3032 info
->name
, modmagic
, vermagic
);
3036 if (!get_modinfo(info
, "intree")) {
3037 if (!test_taint(TAINT_OOT_MODULE
))
3038 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3040 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
3043 check_modinfo_retpoline(mod
, info
);
3045 if (get_modinfo(info
, "staging")) {
3046 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
3047 pr_warn("%s: module is from the staging directory, the quality "
3048 "is unknown, you have been warned.\n", mod
->name
);
3051 err
= check_modinfo_livepatch(mod
, info
);
3055 /* Set up license info based on the info section */
3056 set_license(mod
, get_modinfo(info
, "license"));
3061 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
3063 mod
->kp
= section_objs(info
, "__param",
3064 sizeof(*mod
->kp
), &mod
->num_kp
);
3065 mod
->syms
= section_objs(info
, "__ksymtab",
3066 sizeof(*mod
->syms
), &mod
->num_syms
);
3067 mod
->crcs
= section_addr(info
, "__kcrctab");
3068 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
3069 sizeof(*mod
->gpl_syms
),
3070 &mod
->num_gpl_syms
);
3071 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
3072 mod
->gpl_future_syms
= section_objs(info
,
3073 "__ksymtab_gpl_future",
3074 sizeof(*mod
->gpl_future_syms
),
3075 &mod
->num_gpl_future_syms
);
3076 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
3078 #ifdef CONFIG_UNUSED_SYMBOLS
3079 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
3080 sizeof(*mod
->unused_syms
),
3081 &mod
->num_unused_syms
);
3082 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
3083 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
3084 sizeof(*mod
->unused_gpl_syms
),
3085 &mod
->num_unused_gpl_syms
);
3086 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
3088 #ifdef CONFIG_CONSTRUCTORS
3089 mod
->ctors
= section_objs(info
, ".ctors",
3090 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3092 mod
->ctors
= section_objs(info
, ".init_array",
3093 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3094 else if (find_sec(info
, ".init_array")) {
3096 * This shouldn't happen with same compiler and binutils
3097 * building all parts of the module.
3099 pr_warn("%s: has both .ctors and .init_array.\n",
3105 #ifdef CONFIG_TRACEPOINTS
3106 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
3107 sizeof(*mod
->tracepoints_ptrs
),
3108 &mod
->num_tracepoints
);
3110 #ifdef HAVE_JUMP_LABEL
3111 mod
->jump_entries
= section_objs(info
, "__jump_table",
3112 sizeof(*mod
->jump_entries
),
3113 &mod
->num_jump_entries
);
3115 #ifdef CONFIG_EVENT_TRACING
3116 mod
->trace_events
= section_objs(info
, "_ftrace_events",
3117 sizeof(*mod
->trace_events
),
3118 &mod
->num_trace_events
);
3119 mod
->trace_evals
= section_objs(info
, "_ftrace_eval_map",
3120 sizeof(*mod
->trace_evals
),
3121 &mod
->num_trace_evals
);
3123 #ifdef CONFIG_TRACING
3124 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
3125 sizeof(*mod
->trace_bprintk_fmt_start
),
3126 &mod
->num_trace_bprintk_fmt
);
3128 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3129 /* sechdrs[0].sh_size is always zero */
3130 mod
->ftrace_callsites
= section_objs(info
, "__mcount_loc",
3131 sizeof(*mod
->ftrace_callsites
),
3132 &mod
->num_ftrace_callsites
);
3135 mod
->extable
= section_objs(info
, "__ex_table",
3136 sizeof(*mod
->extable
), &mod
->num_exentries
);
3138 if (section_addr(info
, "__obsparm"))
3139 pr_warn("%s: Ignoring obsolete parameters\n", mod
->name
);
3141 info
->debug
= section_objs(info
, "__verbose",
3142 sizeof(*info
->debug
), &info
->num_debug
);
3147 static int move_module(struct module
*mod
, struct load_info
*info
)
3152 /* Do the allocs. */
3153 ptr
= module_alloc(mod
->core_layout
.size
);
3155 * The pointer to this block is stored in the module structure
3156 * which is inside the block. Just mark it as not being a
3159 kmemleak_not_leak(ptr
);
3163 memset(ptr
, 0, mod
->core_layout
.size
);
3164 mod
->core_layout
.base
= ptr
;
3166 if (mod
->init_layout
.size
) {
3167 ptr
= module_alloc(mod
->init_layout
.size
);
3169 * The pointer to this block is stored in the module structure
3170 * which is inside the block. This block doesn't need to be
3171 * scanned as it contains data and code that will be freed
3172 * after the module is initialized.
3174 kmemleak_ignore(ptr
);
3176 module_memfree(mod
->core_layout
.base
);
3179 memset(ptr
, 0, mod
->init_layout
.size
);
3180 mod
->init_layout
.base
= ptr
;
3182 mod
->init_layout
.base
= NULL
;
3184 /* Transfer each section which specifies SHF_ALLOC */
3185 pr_debug("final section addresses:\n");
3186 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
3188 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3190 if (!(shdr
->sh_flags
& SHF_ALLOC
))
3193 if (shdr
->sh_entsize
& INIT_OFFSET_MASK
)
3194 dest
= mod
->init_layout
.base
3195 + (shdr
->sh_entsize
& ~INIT_OFFSET_MASK
);
3197 dest
= mod
->core_layout
.base
+ shdr
->sh_entsize
;
3199 if (shdr
->sh_type
!= SHT_NOBITS
)
3200 memcpy(dest
, (void *)shdr
->sh_addr
, shdr
->sh_size
);
3201 /* Update sh_addr to point to copy in image. */
3202 shdr
->sh_addr
= (unsigned long)dest
;
3203 pr_debug("\t0x%lx %s\n",
3204 (long)shdr
->sh_addr
, info
->secstrings
+ shdr
->sh_name
);
3210 static int check_module_license_and_versions(struct module
*mod
)
3212 int prev_taint
= test_taint(TAINT_PROPRIETARY_MODULE
);
3215 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3216 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3217 * using GPL-only symbols it needs.
3219 if (strcmp(mod
->name
, "ndiswrapper") == 0)
3220 add_taint(TAINT_PROPRIETARY_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
3222 /* driverloader was caught wrongly pretending to be under GPL */
3223 if (strcmp(mod
->name
, "driverloader") == 0)
3224 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3225 LOCKDEP_NOW_UNRELIABLE
);
3227 /* lve claims to be GPL but upstream won't provide source */
3228 if (strcmp(mod
->name
, "lve") == 0)
3229 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3230 LOCKDEP_NOW_UNRELIABLE
);
3232 if (!prev_taint
&& test_taint(TAINT_PROPRIETARY_MODULE
))
3233 pr_warn("%s: module license taints kernel.\n", mod
->name
);
3235 #ifdef CONFIG_MODVERSIONS
3236 if ((mod
->num_syms
&& !mod
->crcs
)
3237 || (mod
->num_gpl_syms
&& !mod
->gpl_crcs
)
3238 || (mod
->num_gpl_future_syms
&& !mod
->gpl_future_crcs
)
3239 #ifdef CONFIG_UNUSED_SYMBOLS
3240 || (mod
->num_unused_syms
&& !mod
->unused_crcs
)
3241 || (mod
->num_unused_gpl_syms
&& !mod
->unused_gpl_crcs
)
3244 return try_to_force_load(mod
,
3245 "no versions for exported symbols");
3251 static void flush_module_icache(const struct module
*mod
)
3253 mm_segment_t old_fs
;
3255 /* flush the icache in correct context */
3260 * Flush the instruction cache, since we've played with text.
3261 * Do it before processing of module parameters, so the module
3262 * can provide parameter accessor functions of its own.
3264 if (mod
->init_layout
.base
)
3265 flush_icache_range((unsigned long)mod
->init_layout
.base
,
3266 (unsigned long)mod
->init_layout
.base
3267 + mod
->init_layout
.size
);
3268 flush_icache_range((unsigned long)mod
->core_layout
.base
,
3269 (unsigned long)mod
->core_layout
.base
+ mod
->core_layout
.size
);
3274 int __weak
module_frob_arch_sections(Elf_Ehdr
*hdr
,
3282 /* module_blacklist is a comma-separated list of module names */
3283 static char *module_blacklist
;
3284 static bool blacklisted(const char *module_name
)
3289 if (!module_blacklist
)
3292 for (p
= module_blacklist
; *p
; p
+= len
) {
3293 len
= strcspn(p
, ",");
3294 if (strlen(module_name
) == len
&& !memcmp(module_name
, p
, len
))
3301 core_param(module_blacklist
, module_blacklist
, charp
, 0400);
3303 static struct module
*layout_and_allocate(struct load_info
*info
, int flags
)
3305 /* Module within temporary copy. */
3310 mod
= setup_load_info(info
, flags
);
3314 if (blacklisted(info
->name
))
3315 return ERR_PTR(-EPERM
);
3317 err
= check_modinfo(mod
, info
, flags
);
3319 return ERR_PTR(err
);
3321 /* Allow arches to frob section contents and sizes. */
3322 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3323 info
->secstrings
, mod
);
3325 return ERR_PTR(err
);
3327 /* We will do a special allocation for per-cpu sections later. */
3328 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3331 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3332 * layout_sections() can put it in the right place.
3333 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3335 ndx
= find_sec(info
, ".data..ro_after_init");
3337 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3339 /* Determine total sizes, and put offsets in sh_entsize. For now
3340 this is done generically; there doesn't appear to be any
3341 special cases for the architectures. */
3342 layout_sections(mod
, info
);
3343 layout_symtab(mod
, info
);
3345 /* Allocate and move to the final place */
3346 err
= move_module(mod
, info
);
3348 return ERR_PTR(err
);
3350 /* Module has been copied to its final place now: return it. */
3351 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3352 kmemleak_load_module(mod
, info
);
3356 /* mod is no longer valid after this! */
3357 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3359 percpu_modfree(mod
);
3360 module_arch_freeing_init(mod
);
3361 module_memfree(mod
->init_layout
.base
);
3362 module_memfree(mod
->core_layout
.base
);
3365 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3366 const Elf_Shdr
*sechdrs
,
3372 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3374 /* Sort exception table now relocations are done. */
3375 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3377 /* Copy relocated percpu area over. */
3378 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3379 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3381 /* Setup kallsyms-specific fields. */
3382 add_kallsyms(mod
, info
);
3384 /* Arch-specific module finalizing. */
3385 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3388 /* Is this module of this name done loading? No locks held. */
3389 static bool finished_loading(const char *name
)
3395 * The module_mutex should not be a heavily contended lock;
3396 * if we get the occasional sleep here, we'll go an extra iteration
3397 * in the wait_event_interruptible(), which is harmless.
3399 sched_annotate_sleep();
3400 mutex_lock(&module_mutex
);
3401 mod
= find_module_all(name
, strlen(name
), true);
3402 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
3403 || mod
->state
== MODULE_STATE_GOING
;
3404 mutex_unlock(&module_mutex
);
3409 /* Call module constructors. */
3410 static void do_mod_ctors(struct module
*mod
)
3412 #ifdef CONFIG_CONSTRUCTORS
3415 for (i
= 0; i
< mod
->num_ctors
; i
++)
3420 /* For freeing module_init on success, in case kallsyms traversing */
3421 struct mod_initfree
{
3422 struct rcu_head rcu
;
3426 static void do_free_init(struct rcu_head
*head
)
3428 struct mod_initfree
*m
= container_of(head
, struct mod_initfree
, rcu
);
3429 module_memfree(m
->module_init
);
3434 * This is where the real work happens.
3436 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3437 * helper command 'lx-symbols'.
3439 static noinline
int do_init_module(struct module
*mod
)
3442 struct mod_initfree
*freeinit
;
3444 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3449 freeinit
->module_init
= mod
->init_layout
.base
;
3452 * We want to find out whether @mod uses async during init. Clear
3453 * PF_USED_ASYNC. async_schedule*() will set it.
3455 current
->flags
&= ~PF_USED_ASYNC
;
3458 /* Start the module */
3459 if (mod
->init
!= NULL
)
3460 ret
= do_one_initcall(mod
->init
);
3462 goto fail_free_freeinit
;
3465 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3466 "follow 0/-E convention\n"
3467 "%s: loading module anyway...\n",
3468 __func__
, mod
->name
, ret
, __func__
);
3472 /* Now it's a first class citizen! */
3473 mod
->state
= MODULE_STATE_LIVE
;
3474 blocking_notifier_call_chain(&module_notify_list
,
3475 MODULE_STATE_LIVE
, mod
);
3478 * We need to finish all async code before the module init sequence
3479 * is done. This has potential to deadlock. For example, a newly
3480 * detected block device can trigger request_module() of the
3481 * default iosched from async probing task. Once userland helper
3482 * reaches here, async_synchronize_full() will wait on the async
3483 * task waiting on request_module() and deadlock.
3485 * This deadlock is avoided by perfomring async_synchronize_full()
3486 * iff module init queued any async jobs. This isn't a full
3487 * solution as it will deadlock the same if module loading from
3488 * async jobs nests more than once; however, due to the various
3489 * constraints, this hack seems to be the best option for now.
3490 * Please refer to the following thread for details.
3492 * http://thread.gmane.org/gmane.linux.kernel/1420814
3494 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3495 async_synchronize_full();
3497 ftrace_free_mem(mod
, mod
->init_layout
.base
, mod
->init_layout
.base
+
3498 mod
->init_layout
.size
);
3499 mutex_lock(&module_mutex
);
3500 /* Drop initial reference. */
3502 trim_init_extable(mod
);
3503 #ifdef CONFIG_KALLSYMS
3504 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3505 rcu_assign_pointer(mod
->kallsyms
, &mod
->core_kallsyms
);
3507 module_enable_ro(mod
, true);
3508 mod_tree_remove_init(mod
);
3509 disable_ro_nx(&mod
->init_layout
);
3510 module_arch_freeing_init(mod
);
3511 mod
->init_layout
.base
= NULL
;
3512 mod
->init_layout
.size
= 0;
3513 mod
->init_layout
.ro_size
= 0;
3514 mod
->init_layout
.ro_after_init_size
= 0;
3515 mod
->init_layout
.text_size
= 0;
3517 * We want to free module_init, but be aware that kallsyms may be
3518 * walking this with preempt disabled. In all the failure paths, we
3519 * call synchronize_sched(), but we don't want to slow down the success
3520 * path, so use actual RCU here.
3521 * Note that module_alloc() on most architectures creates W+X page
3522 * mappings which won't be cleaned up until do_free_init() runs. Any
3523 * code such as mark_rodata_ro() which depends on those mappings to
3524 * be cleaned up needs to sync with the queued work - ie
3525 * rcu_barrier_sched()
3527 call_rcu_sched(&freeinit
->rcu
, do_free_init
);
3528 mutex_unlock(&module_mutex
);
3529 wake_up_all(&module_wq
);
3536 /* Try to protect us from buggy refcounters. */
3537 mod
->state
= MODULE_STATE_GOING
;
3538 synchronize_sched();
3540 blocking_notifier_call_chain(&module_notify_list
,
3541 MODULE_STATE_GOING
, mod
);
3542 klp_module_going(mod
);
3543 ftrace_release_mod(mod
);
3545 wake_up_all(&module_wq
);
3549 static int may_init_module(void)
3551 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3558 * We try to place it in the list now to make sure it's unique before
3559 * we dedicate too many resources. In particular, temporary percpu
3560 * memory exhaustion.
3562 static int add_unformed_module(struct module
*mod
)
3567 mod
->state
= MODULE_STATE_UNFORMED
;
3570 mutex_lock(&module_mutex
);
3571 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3573 if (old
->state
== MODULE_STATE_COMING
3574 || old
->state
== MODULE_STATE_UNFORMED
) {
3575 /* Wait in case it fails to load. */
3576 mutex_unlock(&module_mutex
);
3577 err
= wait_event_interruptible(module_wq
,
3578 finished_loading(mod
->name
));
3586 mod_update_bounds(mod
);
3587 list_add_rcu(&mod
->list
, &modules
);
3588 mod_tree_insert(mod
);
3592 mutex_unlock(&module_mutex
);
3597 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3601 mutex_lock(&module_mutex
);
3603 /* Find duplicate symbols (must be called under lock). */
3604 err
= verify_export_symbols(mod
);
3608 /* This relies on module_mutex for list integrity. */
3609 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3611 module_enable_ro(mod
, false);
3612 module_enable_nx(mod
);
3614 /* Mark state as coming so strong_try_module_get() ignores us,
3615 * but kallsyms etc. can see us. */
3616 mod
->state
= MODULE_STATE_COMING
;
3617 mutex_unlock(&module_mutex
);
3622 mutex_unlock(&module_mutex
);
3626 static int prepare_coming_module(struct module
*mod
)
3630 ftrace_module_enable(mod
);
3631 err
= klp_module_coming(mod
);
3635 blocking_notifier_call_chain(&module_notify_list
,
3636 MODULE_STATE_COMING
, mod
);
3640 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3643 struct module
*mod
= arg
;
3646 if (strcmp(param
, "async_probe") == 0) {
3647 mod
->async_probe_requested
= true;
3651 /* Check for magic 'dyndbg' arg */
3652 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3654 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3658 /* Allocate and load the module: note that size of section 0 is always
3659 zero, and we rely on this for optional sections. */
3660 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3667 err
= module_sig_check(info
, flags
);
3671 err
= elf_header_check(info
);
3675 /* Figure out module layout, and allocate all the memory. */
3676 mod
= layout_and_allocate(info
, flags
);
3682 audit_log_kern_module(mod
->name
);
3684 /* Reserve our place in the list. */
3685 err
= add_unformed_module(mod
);
3689 #ifdef CONFIG_MODULE_SIG
3690 mod
->sig_ok
= info
->sig_ok
;
3692 pr_notice_once("%s: module verification failed: signature "
3693 "and/or required key missing - tainting "
3694 "kernel\n", mod
->name
);
3695 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3699 /* To avoid stressing percpu allocator, do this once we're unique. */
3700 err
= percpu_modalloc(mod
, info
);
3704 /* Now module is in final location, initialize linked lists, etc. */
3705 err
= module_unload_init(mod
);
3709 init_param_lock(mod
);
3711 /* Now we've got everything in the final locations, we can
3712 * find optional sections. */
3713 err
= find_module_sections(mod
, info
);
3717 err
= check_module_license_and_versions(mod
);
3721 /* Set up MODINFO_ATTR fields */
3722 setup_modinfo(mod
, info
);
3724 /* Fix up syms, so that st_value is a pointer to location. */
3725 err
= simplify_symbols(mod
, info
);
3729 err
= apply_relocations(mod
, info
);
3733 err
= post_relocation(mod
, info
);
3737 flush_module_icache(mod
);
3739 /* Now copy in args */
3740 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3741 if (IS_ERR(mod
->args
)) {
3742 err
= PTR_ERR(mod
->args
);
3743 goto free_arch_cleanup
;
3746 dynamic_debug_setup(mod
, info
->debug
, info
->num_debug
);
3748 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3749 ftrace_module_init(mod
);
3751 /* Finally it's fully formed, ready to start executing. */
3752 err
= complete_formation(mod
, info
);
3754 goto ddebug_cleanup
;
3756 err
= prepare_coming_module(mod
);
3760 /* Module is ready to execute: parsing args may do that. */
3761 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3763 unknown_module_param_cb
);
3764 if (IS_ERR(after_dashes
)) {
3765 err
= PTR_ERR(after_dashes
);
3766 goto coming_cleanup
;
3767 } else if (after_dashes
) {
3768 pr_warn("%s: parameters '%s' after `--' ignored\n",
3769 mod
->name
, after_dashes
);
3772 /* Link in to sysfs. */
3773 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3775 goto coming_cleanup
;
3777 if (is_livepatch_module(mod
)) {
3778 err
= copy_module_elf(mod
, info
);
3783 /* Get rid of temporary copy. */
3787 trace_module_load(mod
);
3789 return do_init_module(mod
);
3792 mod_sysfs_teardown(mod
);
3794 mod
->state
= MODULE_STATE_GOING
;
3795 destroy_params(mod
->kp
, mod
->num_kp
);
3796 blocking_notifier_call_chain(&module_notify_list
,
3797 MODULE_STATE_GOING
, mod
);
3798 klp_module_going(mod
);
3800 /* module_bug_cleanup needs module_mutex protection */
3801 mutex_lock(&module_mutex
);
3802 module_bug_cleanup(mod
);
3803 mutex_unlock(&module_mutex
);
3805 /* we can't deallocate the module until we clear memory protection */
3806 module_disable_ro(mod
);
3807 module_disable_nx(mod
);
3810 dynamic_debug_remove(mod
, info
->debug
);
3811 synchronize_sched();
3814 module_arch_cleanup(mod
);
3818 module_unload_free(mod
);
3820 mutex_lock(&module_mutex
);
3821 /* Unlink carefully: kallsyms could be walking list. */
3822 list_del_rcu(&mod
->list
);
3823 mod_tree_remove(mod
);
3824 wake_up_all(&module_wq
);
3825 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3826 synchronize_sched();
3827 mutex_unlock(&module_mutex
);
3830 * Ftrace needs to clean up what it initialized.
3831 * This does nothing if ftrace_module_init() wasn't called,
3832 * but it must be called outside of module_mutex.
3834 ftrace_release_mod(mod
);
3835 /* Free lock-classes; relies on the preceding sync_rcu() */
3836 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
3838 module_deallocate(mod
, info
);
3844 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
3845 unsigned long, len
, const char __user
*, uargs
)
3848 struct load_info info
= { };
3850 err
= may_init_module();
3854 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3857 err
= copy_module_from_user(umod
, len
, &info
);
3861 return load_module(&info
, uargs
, 0);
3864 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
3866 struct load_info info
= { };
3871 err
= may_init_module();
3875 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
3877 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
3878 |MODULE_INIT_IGNORE_VERMAGIC
))
3881 err
= kernel_read_file_from_fd(fd
, &hdr
, &size
, INT_MAX
,
3888 return load_module(&info
, uargs
, flags
);
3891 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
3893 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
3896 #ifdef CONFIG_KALLSYMS
3898 * This ignores the intensely annoying "mapping symbols" found
3899 * in ARM ELF files: $a, $t and $d.
3901 static inline int is_arm_mapping_symbol(const char *str
)
3903 if (str
[0] == '.' && str
[1] == 'L')
3905 return str
[0] == '$' && strchr("axtd", str
[1])
3906 && (str
[2] == '\0' || str
[2] == '.');
3909 static const char *symname(struct mod_kallsyms
*kallsyms
, unsigned int symnum
)
3911 return kallsyms
->strtab
+ kallsyms
->symtab
[symnum
].st_name
;
3914 static const char *get_ksymbol(struct module
*mod
,
3916 unsigned long *size
,
3917 unsigned long *offset
)
3919 unsigned int i
, best
= 0;
3920 unsigned long nextval
;
3921 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
3923 /* At worse, next value is at end of module */
3924 if (within_module_init(addr
, mod
))
3925 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
3927 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
3929 /* Scan for closest preceding symbol, and next symbol. (ELF
3930 starts real symbols at 1). */
3931 for (i
= 1; i
< kallsyms
->num_symtab
; i
++) {
3932 if (kallsyms
->symtab
[i
].st_shndx
== SHN_UNDEF
)
3935 /* We ignore unnamed symbols: they're uninformative
3936 * and inserted at a whim. */
3937 if (*symname(kallsyms
, i
) == '\0'
3938 || is_arm_mapping_symbol(symname(kallsyms
, i
)))
3941 if (kallsyms
->symtab
[i
].st_value
<= addr
3942 && kallsyms
->symtab
[i
].st_value
> kallsyms
->symtab
[best
].st_value
)
3944 if (kallsyms
->symtab
[i
].st_value
> addr
3945 && kallsyms
->symtab
[i
].st_value
< nextval
)
3946 nextval
= kallsyms
->symtab
[i
].st_value
;
3953 *size
= nextval
- kallsyms
->symtab
[best
].st_value
;
3955 *offset
= addr
- kallsyms
->symtab
[best
].st_value
;
3956 return symname(kallsyms
, best
);
3959 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3960 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3961 const char *module_address_lookup(unsigned long addr
,
3962 unsigned long *size
,
3963 unsigned long *offset
,
3967 const char *ret
= NULL
;
3971 mod
= __module_address(addr
);
3974 *modname
= mod
->name
;
3975 ret
= get_ksymbol(mod
, addr
, size
, offset
);
3977 /* Make a copy in here where it's safe */
3979 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
3987 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
3992 list_for_each_entry_rcu(mod
, &modules
, list
) {
3993 if (mod
->state
== MODULE_STATE_UNFORMED
)
3995 if (within_module(addr
, mod
)) {
3998 sym
= get_ksymbol(mod
, addr
, NULL
, NULL
);
4001 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
4011 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
4012 unsigned long *offset
, char *modname
, char *name
)
4017 list_for_each_entry_rcu(mod
, &modules
, list
) {
4018 if (mod
->state
== MODULE_STATE_UNFORMED
)
4020 if (within_module(addr
, mod
)) {
4023 sym
= get_ksymbol(mod
, addr
, size
, offset
);
4027 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
4029 strlcpy(name
, sym
, KSYM_NAME_LEN
);
4039 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
4040 char *name
, char *module_name
, int *exported
)
4045 list_for_each_entry_rcu(mod
, &modules
, list
) {
4046 struct mod_kallsyms
*kallsyms
;
4048 if (mod
->state
== MODULE_STATE_UNFORMED
)
4050 kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4051 if (symnum
< kallsyms
->num_symtab
) {
4052 *value
= kallsyms
->symtab
[symnum
].st_value
;
4053 *type
= kallsyms
->symtab
[symnum
].st_info
;
4054 strlcpy(name
, symname(kallsyms
, symnum
), KSYM_NAME_LEN
);
4055 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
4056 *exported
= is_exported(name
, *value
, mod
);
4060 symnum
-= kallsyms
->num_symtab
;
4066 static unsigned long mod_find_symname(struct module
*mod
, const char *name
)
4069 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4071 for (i
= 0; i
< kallsyms
->num_symtab
; i
++)
4072 if (strcmp(name
, symname(kallsyms
, i
)) == 0 &&
4073 kallsyms
->symtab
[i
].st_shndx
!= SHN_UNDEF
)
4074 return kallsyms
->symtab
[i
].st_value
;
4078 /* Look for this name: can be of form module:name. */
4079 unsigned long module_kallsyms_lookup_name(const char *name
)
4083 unsigned long ret
= 0;
4085 /* Don't lock: we're in enough trouble already. */
4087 if ((colon
= strnchr(name
, MODULE_NAME_LEN
, ':')) != NULL
) {
4088 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
4089 ret
= mod_find_symname(mod
, colon
+1);
4091 list_for_each_entry_rcu(mod
, &modules
, list
) {
4092 if (mod
->state
== MODULE_STATE_UNFORMED
)
4094 if ((ret
= mod_find_symname(mod
, name
)) != 0)
4102 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
4103 struct module
*, unsigned long),
4110 module_assert_mutex();
4112 list_for_each_entry(mod
, &modules
, list
) {
4113 /* We hold module_mutex: no need for rcu_dereference_sched */
4114 struct mod_kallsyms
*kallsyms
= mod
->kallsyms
;
4116 if (mod
->state
== MODULE_STATE_UNFORMED
)
4118 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4120 if (kallsyms
->symtab
[i
].st_shndx
== SHN_UNDEF
)
4123 ret
= fn(data
, symname(kallsyms
, i
),
4124 mod
, kallsyms
->symtab
[i
].st_value
);
4131 #endif /* CONFIG_KALLSYMS */
4133 /* Maximum number of characters written by module_flags() */
4134 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4136 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4137 static char *module_flags(struct module
*mod
, char *buf
)
4141 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
4143 mod
->state
== MODULE_STATE_GOING
||
4144 mod
->state
== MODULE_STATE_COMING
) {
4146 bx
+= module_flags_taint(mod
, buf
+ bx
);
4147 /* Show a - for module-is-being-unloaded */
4148 if (mod
->state
== MODULE_STATE_GOING
)
4150 /* Show a + for module-is-being-loaded */
4151 if (mod
->state
== MODULE_STATE_COMING
)
4160 #ifdef CONFIG_PROC_FS
4161 /* Called by the /proc file system to return a list of modules. */
4162 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
4164 mutex_lock(&module_mutex
);
4165 return seq_list_start(&modules
, *pos
);
4168 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
4170 return seq_list_next(p
, &modules
, pos
);
4173 static void m_stop(struct seq_file
*m
, void *p
)
4175 mutex_unlock(&module_mutex
);
4178 static int m_show(struct seq_file
*m
, void *p
)
4180 struct module
*mod
= list_entry(p
, struct module
, list
);
4181 char buf
[MODULE_FLAGS_BUF_SIZE
];
4184 /* We always ignore unformed modules. */
4185 if (mod
->state
== MODULE_STATE_UNFORMED
)
4188 seq_printf(m
, "%s %u",
4189 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
4190 print_unload_info(m
, mod
);
4192 /* Informative for users. */
4193 seq_printf(m
, " %s",
4194 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
4195 mod
->state
== MODULE_STATE_COMING
? "Loading" :
4197 /* Used by oprofile and other similar tools. */
4198 value
= m
->private ? NULL
: mod
->core_layout
.base
;
4199 seq_printf(m
, " 0x%px", value
);
4203 seq_printf(m
, " %s", module_flags(mod
, buf
));
4209 /* Format: modulename size refcount deps address
4211 Where refcount is a number or -, and deps is a comma-separated list
4214 static const struct seq_operations modules_op
= {
4222 * This also sets the "private" pointer to non-NULL if the
4223 * kernel pointers should be hidden (so you can just test
4224 * "m->private" to see if you should keep the values private).
4226 * We use the same logic as for /proc/kallsyms.
4228 static int modules_open(struct inode
*inode
, struct file
*file
)
4230 int err
= seq_open(file
, &modules_op
);
4233 struct seq_file
*m
= file
->private_data
;
4234 m
->private = kallsyms_show_value() ? NULL
: (void *)8ul;
4240 static const struct file_operations proc_modules_operations
= {
4241 .open
= modules_open
,
4243 .llseek
= seq_lseek
,
4244 .release
= seq_release
,
4247 static int __init
proc_modules_init(void)
4249 proc_create("modules", 0, NULL
, &proc_modules_operations
);
4252 module_init(proc_modules_init
);
4255 /* Given an address, look for it in the module exception tables. */
4256 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
4258 const struct exception_table_entry
*e
= NULL
;
4262 mod
= __module_address(addr
);
4266 if (!mod
->num_exentries
)
4269 e
= search_extable(mod
->extable
,
4276 * Now, if we found one, we are running inside it now, hence
4277 * we cannot unload the module, hence no refcnt needed.
4283 * is_module_address - is this address inside a module?
4284 * @addr: the address to check.
4286 * See is_module_text_address() if you simply want to see if the address
4287 * is code (not data).
4289 bool is_module_address(unsigned long addr
)
4294 ret
= __module_address(addr
) != NULL
;
4301 * __module_address - get the module which contains an address.
4302 * @addr: the address.
4304 * Must be called with preempt disabled or module mutex held so that
4305 * module doesn't get freed during this.
4307 struct module
*__module_address(unsigned long addr
)
4311 if (addr
< module_addr_min
|| addr
> module_addr_max
)
4314 module_assert_mutex_or_preempt();
4316 mod
= mod_find(addr
);
4318 BUG_ON(!within_module(addr
, mod
));
4319 if (mod
->state
== MODULE_STATE_UNFORMED
)
4324 EXPORT_SYMBOL_GPL(__module_address
);
4327 * is_module_text_address - is this address inside module code?
4328 * @addr: the address to check.
4330 * See is_module_address() if you simply want to see if the address is
4331 * anywhere in a module. See kernel_text_address() for testing if an
4332 * address corresponds to kernel or module code.
4334 bool is_module_text_address(unsigned long addr
)
4339 ret
= __module_text_address(addr
) != NULL
;
4346 * __module_text_address - get the module whose code contains an address.
4347 * @addr: the address.
4349 * Must be called with preempt disabled or module mutex held so that
4350 * module doesn't get freed during this.
4352 struct module
*__module_text_address(unsigned long addr
)
4354 struct module
*mod
= __module_address(addr
);
4356 /* Make sure it's within the text section. */
4357 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4358 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4363 EXPORT_SYMBOL_GPL(__module_text_address
);
4365 /* Don't grab lock, we're oopsing. */
4366 void print_modules(void)
4369 char buf
[MODULE_FLAGS_BUF_SIZE
];
4371 printk(KERN_DEFAULT
"Modules linked in:");
4372 /* Most callers should already have preempt disabled, but make sure */
4374 list_for_each_entry_rcu(mod
, &modules
, list
) {
4375 if (mod
->state
== MODULE_STATE_UNFORMED
)
4377 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4380 if (last_unloaded_module
[0])
4381 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4385 #ifdef CONFIG_MODVERSIONS
4386 /* Generate the signature for all relevant module structures here.
4387 * If these change, we don't want to try to parse the module. */
4388 void module_layout(struct module
*mod
,
4389 struct modversion_info
*ver
,
4390 struct kernel_param
*kp
,
4391 struct kernel_symbol
*ks
,
4392 struct tracepoint
* const *tp
)
4395 EXPORT_SYMBOL(module_layout
);