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
)
1214 rc
= kobject_synth_uevent(&mk
->kobj
, buffer
, count
);
1215 return rc
? rc
: count
;
1218 struct module_attribute module_uevent
=
1219 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1221 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1222 struct module_kobject
*mk
, char *buffer
)
1224 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1227 static struct module_attribute modinfo_coresize
=
1228 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1230 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1231 struct module_kobject
*mk
, char *buffer
)
1233 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1236 static struct module_attribute modinfo_initsize
=
1237 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1239 static ssize_t
show_taint(struct module_attribute
*mattr
,
1240 struct module_kobject
*mk
, char *buffer
)
1244 l
= module_flags_taint(mk
->mod
, buffer
);
1249 static struct module_attribute modinfo_taint
=
1250 __ATTR(taint
, 0444, show_taint
, NULL
);
1252 static struct module_attribute
*modinfo_attrs
[] = {
1255 &modinfo_srcversion
,
1260 #ifdef CONFIG_MODULE_UNLOAD
1266 static const char vermagic
[] = VERMAGIC_STRING
;
1268 static int try_to_force_load(struct module
*mod
, const char *reason
)
1270 #ifdef CONFIG_MODULE_FORCE_LOAD
1271 if (!test_taint(TAINT_FORCED_MODULE
))
1272 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1273 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1280 #ifdef CONFIG_MODVERSIONS
1282 static u32
resolve_rel_crc(const s32
*crc
)
1284 return *(u32
*)((void *)crc
+ *crc
);
1287 static int check_version(const struct load_info
*info
,
1288 const char *symname
,
1292 Elf_Shdr
*sechdrs
= info
->sechdrs
;
1293 unsigned int versindex
= info
->index
.vers
;
1294 unsigned int i
, num_versions
;
1295 struct modversion_info
*versions
;
1297 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1301 /* No versions at all? modprobe --force does this. */
1303 return try_to_force_load(mod
, symname
) == 0;
1305 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1306 num_versions
= sechdrs
[versindex
].sh_size
1307 / sizeof(struct modversion_info
);
1309 for (i
= 0; i
< num_versions
; i
++) {
1312 if (strcmp(versions
[i
].name
, symname
) != 0)
1315 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS
))
1316 crcval
= resolve_rel_crc(crc
);
1319 if (versions
[i
].crc
== crcval
)
1321 pr_debug("Found checksum %X vs module %lX\n",
1322 crcval
, versions
[i
].crc
);
1326 /* Broken toolchain. Warn once, then let it go.. */
1327 pr_warn_once("%s: no symbol version for %s\n", info
->name
, symname
);
1331 pr_warn("%s: disagrees about version of symbol %s\n",
1332 info
->name
, symname
);
1336 static inline int check_modstruct_version(const struct load_info
*info
,
1342 * Since this should be found in kernel (which can't be removed), no
1343 * locking is necessary -- use preempt_disable() to placate lockdep.
1346 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout
), NULL
,
1347 &crc
, true, false)) {
1352 return check_version(info
, VMLINUX_SYMBOL_STR(module_layout
),
1356 /* First part is kernel version, which we ignore if module has crcs. */
1357 static inline int same_magic(const char *amagic
, const char *bmagic
,
1361 amagic
+= strcspn(amagic
, " ");
1362 bmagic
+= strcspn(bmagic
, " ");
1364 return strcmp(amagic
, bmagic
) == 0;
1367 static inline int check_version(const struct load_info
*info
,
1368 const char *symname
,
1375 static inline int check_modstruct_version(const struct load_info
*info
,
1381 static inline int same_magic(const char *amagic
, const char *bmagic
,
1384 return strcmp(amagic
, bmagic
) == 0;
1386 #endif /* CONFIG_MODVERSIONS */
1388 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1389 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1390 const struct load_info
*info
,
1394 struct module
*owner
;
1395 const struct kernel_symbol
*sym
;
1400 * The module_mutex should not be a heavily contended lock;
1401 * if we get the occasional sleep here, we'll go an extra iteration
1402 * in the wait_event_interruptible(), which is harmless.
1404 sched_annotate_sleep();
1405 mutex_lock(&module_mutex
);
1406 sym
= find_symbol(name
, &owner
, &crc
,
1407 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1411 if (!check_version(info
, name
, mod
, crc
)) {
1412 sym
= ERR_PTR(-EINVAL
);
1416 err
= ref_module(mod
, owner
);
1423 /* We must make copy under the lock if we failed to get ref. */
1424 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1426 mutex_unlock(&module_mutex
);
1430 static const struct kernel_symbol
*
1431 resolve_symbol_wait(struct module
*mod
,
1432 const struct load_info
*info
,
1435 const struct kernel_symbol
*ksym
;
1436 char owner
[MODULE_NAME_LEN
];
1438 if (wait_event_interruptible_timeout(module_wq
,
1439 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1440 || PTR_ERR(ksym
) != -EBUSY
,
1442 pr_warn("%s: gave up waiting for init of module %s.\n",
1449 * /sys/module/foo/sections stuff
1450 * J. Corbet <corbet@lwn.net>
1454 #ifdef CONFIG_KALLSYMS
1455 static inline bool sect_empty(const Elf_Shdr
*sect
)
1457 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1460 struct module_sect_attr
{
1461 struct module_attribute mattr
;
1463 unsigned long address
;
1466 struct module_sect_attrs
{
1467 struct attribute_group grp
;
1468 unsigned int nsections
;
1469 struct module_sect_attr attrs
[0];
1472 static ssize_t
module_sect_show(struct module_attribute
*mattr
,
1473 struct module_kobject
*mk
, char *buf
)
1475 struct module_sect_attr
*sattr
=
1476 container_of(mattr
, struct module_sect_attr
, mattr
);
1477 return sprintf(buf
, "0x%px\n", kptr_restrict
< 2 ?
1478 (void *)sattr
->address
: NULL
);
1481 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1483 unsigned int section
;
1485 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1486 kfree(sect_attrs
->attrs
[section
].name
);
1490 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1492 unsigned int nloaded
= 0, i
, size
[2];
1493 struct module_sect_attrs
*sect_attrs
;
1494 struct module_sect_attr
*sattr
;
1495 struct attribute
**gattr
;
1497 /* Count loaded sections and allocate structures */
1498 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1499 if (!sect_empty(&info
->sechdrs
[i
]))
1501 size
[0] = ALIGN(sizeof(*sect_attrs
)
1502 + nloaded
* sizeof(sect_attrs
->attrs
[0]),
1503 sizeof(sect_attrs
->grp
.attrs
[0]));
1504 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.attrs
[0]);
1505 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1506 if (sect_attrs
== NULL
)
1509 /* Setup section attributes. */
1510 sect_attrs
->grp
.name
= "sections";
1511 sect_attrs
->grp
.attrs
= (void *)sect_attrs
+ size
[0];
1513 sect_attrs
->nsections
= 0;
1514 sattr
= §_attrs
->attrs
[0];
1515 gattr
= §_attrs
->grp
.attrs
[0];
1516 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1517 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1518 if (sect_empty(sec
))
1520 sattr
->address
= sec
->sh_addr
;
1521 sattr
->name
= kstrdup(info
->secstrings
+ sec
->sh_name
,
1523 if (sattr
->name
== NULL
)
1525 sect_attrs
->nsections
++;
1526 sysfs_attr_init(&sattr
->mattr
.attr
);
1527 sattr
->mattr
.show
= module_sect_show
;
1528 sattr
->mattr
.store
= NULL
;
1529 sattr
->mattr
.attr
.name
= sattr
->name
;
1530 sattr
->mattr
.attr
.mode
= S_IRUSR
;
1531 *(gattr
++) = &(sattr
++)->mattr
.attr
;
1535 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1538 mod
->sect_attrs
= sect_attrs
;
1541 free_sect_attrs(sect_attrs
);
1544 static void remove_sect_attrs(struct module
*mod
)
1546 if (mod
->sect_attrs
) {
1547 sysfs_remove_group(&mod
->mkobj
.kobj
,
1548 &mod
->sect_attrs
->grp
);
1549 /* We are positive that no one is using any sect attrs
1550 * at this point. Deallocate immediately. */
1551 free_sect_attrs(mod
->sect_attrs
);
1552 mod
->sect_attrs
= NULL
;
1557 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1560 struct module_notes_attrs
{
1561 struct kobject
*dir
;
1563 struct bin_attribute attrs
[0];
1566 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1567 struct bin_attribute
*bin_attr
,
1568 char *buf
, loff_t pos
, size_t count
)
1571 * The caller checked the pos and count against our size.
1573 memcpy(buf
, bin_attr
->private + pos
, count
);
1577 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1580 if (notes_attrs
->dir
) {
1582 sysfs_remove_bin_file(notes_attrs
->dir
,
1583 ¬es_attrs
->attrs
[i
]);
1584 kobject_put(notes_attrs
->dir
);
1589 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1591 unsigned int notes
, loaded
, i
;
1592 struct module_notes_attrs
*notes_attrs
;
1593 struct bin_attribute
*nattr
;
1595 /* failed to create section attributes, so can't create notes */
1596 if (!mod
->sect_attrs
)
1599 /* Count notes sections and allocate structures. */
1601 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1602 if (!sect_empty(&info
->sechdrs
[i
]) &&
1603 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1609 notes_attrs
= kzalloc(sizeof(*notes_attrs
)
1610 + notes
* sizeof(notes_attrs
->attrs
[0]),
1612 if (notes_attrs
== NULL
)
1615 notes_attrs
->notes
= notes
;
1616 nattr
= ¬es_attrs
->attrs
[0];
1617 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1618 if (sect_empty(&info
->sechdrs
[i
]))
1620 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1621 sysfs_bin_attr_init(nattr
);
1622 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].name
;
1623 nattr
->attr
.mode
= S_IRUGO
;
1624 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1625 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1626 nattr
->read
= module_notes_read
;
1632 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1633 if (!notes_attrs
->dir
)
1636 for (i
= 0; i
< notes
; ++i
)
1637 if (sysfs_create_bin_file(notes_attrs
->dir
,
1638 ¬es_attrs
->attrs
[i
]))
1641 mod
->notes_attrs
= notes_attrs
;
1645 free_notes_attrs(notes_attrs
, i
);
1648 static void remove_notes_attrs(struct module
*mod
)
1650 if (mod
->notes_attrs
)
1651 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1656 static inline void add_sect_attrs(struct module
*mod
,
1657 const struct load_info
*info
)
1661 static inline void remove_sect_attrs(struct module
*mod
)
1665 static inline void add_notes_attrs(struct module
*mod
,
1666 const struct load_info
*info
)
1670 static inline void remove_notes_attrs(struct module
*mod
)
1673 #endif /* CONFIG_KALLSYMS */
1675 static void del_usage_links(struct module
*mod
)
1677 #ifdef CONFIG_MODULE_UNLOAD
1678 struct module_use
*use
;
1680 mutex_lock(&module_mutex
);
1681 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1682 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1683 mutex_unlock(&module_mutex
);
1687 static int add_usage_links(struct module
*mod
)
1690 #ifdef CONFIG_MODULE_UNLOAD
1691 struct module_use
*use
;
1693 mutex_lock(&module_mutex
);
1694 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1695 ret
= sysfs_create_link(use
->target
->holders_dir
,
1696 &mod
->mkobj
.kobj
, mod
->name
);
1700 mutex_unlock(&module_mutex
);
1702 del_usage_links(mod
);
1707 static void module_remove_modinfo_attrs(struct module
*mod
, int end
);
1709 static int module_add_modinfo_attrs(struct module
*mod
)
1711 struct module_attribute
*attr
;
1712 struct module_attribute
*temp_attr
;
1716 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1717 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1719 if (!mod
->modinfo_attrs
)
1722 temp_attr
= mod
->modinfo_attrs
;
1723 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
1724 if (!attr
->test
|| attr
->test(mod
)) {
1725 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1726 sysfs_attr_init(&temp_attr
->attr
);
1727 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1739 module_remove_modinfo_attrs(mod
, --i
);
1743 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1745 struct module_attribute
*attr
;
1748 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1749 if (end
>= 0 && i
> end
)
1751 /* pick a field to test for end of list */
1752 if (!attr
->attr
.name
)
1754 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1758 kfree(mod
->modinfo_attrs
);
1761 static void mod_kobject_put(struct module
*mod
)
1763 DECLARE_COMPLETION_ONSTACK(c
);
1764 mod
->mkobj
.kobj_completion
= &c
;
1765 kobject_put(&mod
->mkobj
.kobj
);
1766 wait_for_completion(&c
);
1769 static int mod_sysfs_init(struct module
*mod
)
1772 struct kobject
*kobj
;
1774 if (!module_sysfs_initialized
) {
1775 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1780 kobj
= kset_find_obj(module_kset
, mod
->name
);
1782 pr_err("%s: module is already loaded\n", mod
->name
);
1788 mod
->mkobj
.mod
= mod
;
1790 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1791 mod
->mkobj
.kobj
.kset
= module_kset
;
1792 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1795 mod_kobject_put(mod
);
1797 /* delay uevent until full sysfs population */
1802 static int mod_sysfs_setup(struct module
*mod
,
1803 const struct load_info
*info
,
1804 struct kernel_param
*kparam
,
1805 unsigned int num_params
)
1809 err
= mod_sysfs_init(mod
);
1813 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1814 if (!mod
->holders_dir
) {
1819 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1821 goto out_unreg_holders
;
1823 err
= module_add_modinfo_attrs(mod
);
1825 goto out_unreg_param
;
1827 err
= add_usage_links(mod
);
1829 goto out_unreg_modinfo_attrs
;
1831 add_sect_attrs(mod
, info
);
1832 add_notes_attrs(mod
, info
);
1834 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1837 out_unreg_modinfo_attrs
:
1838 module_remove_modinfo_attrs(mod
, -1);
1840 module_param_sysfs_remove(mod
);
1842 kobject_put(mod
->holders_dir
);
1844 mod_kobject_put(mod
);
1849 static void mod_sysfs_fini(struct module
*mod
)
1851 remove_notes_attrs(mod
);
1852 remove_sect_attrs(mod
);
1853 mod_kobject_put(mod
);
1856 static void init_param_lock(struct module
*mod
)
1858 mutex_init(&mod
->param_lock
);
1860 #else /* !CONFIG_SYSFS */
1862 static int mod_sysfs_setup(struct module
*mod
,
1863 const struct load_info
*info
,
1864 struct kernel_param
*kparam
,
1865 unsigned int num_params
)
1870 static void mod_sysfs_fini(struct module
*mod
)
1874 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1878 static void del_usage_links(struct module
*mod
)
1882 static void init_param_lock(struct module
*mod
)
1885 #endif /* CONFIG_SYSFS */
1887 static void mod_sysfs_teardown(struct module
*mod
)
1889 del_usage_links(mod
);
1890 module_remove_modinfo_attrs(mod
, -1);
1891 module_param_sysfs_remove(mod
);
1892 kobject_put(mod
->mkobj
.drivers_dir
);
1893 kobject_put(mod
->holders_dir
);
1894 mod_sysfs_fini(mod
);
1897 #ifdef CONFIG_STRICT_MODULE_RWX
1899 * LKM RO/NX protection: protect module's text/ro-data
1900 * from modification and any data from execution.
1902 * General layout of module is:
1903 * [text] [read-only-data] [ro-after-init] [writable data]
1904 * text_size -----^ ^ ^ ^
1905 * ro_size ------------------------| | |
1906 * ro_after_init_size -----------------------------| |
1907 * size -----------------------------------------------------------|
1909 * These values are always page-aligned (as is base)
1911 static void frob_text(const struct module_layout
*layout
,
1912 int (*set_memory
)(unsigned long start
, int num_pages
))
1914 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1915 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1916 set_memory((unsigned long)layout
->base
,
1917 layout
->text_size
>> PAGE_SHIFT
);
1920 static void frob_rodata(const struct module_layout
*layout
,
1921 int (*set_memory
)(unsigned long start
, int num_pages
))
1923 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1924 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1925 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1926 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
1927 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
1930 static void frob_ro_after_init(const struct module_layout
*layout
,
1931 int (*set_memory
)(unsigned long start
, int num_pages
))
1933 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1934 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1935 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1936 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
1937 (layout
->ro_after_init_size
- layout
->ro_size
) >> PAGE_SHIFT
);
1940 static void frob_writable_data(const struct module_layout
*layout
,
1941 int (*set_memory
)(unsigned long start
, int num_pages
))
1943 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1944 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1945 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
1946 set_memory((unsigned long)layout
->base
+ layout
->ro_after_init_size
,
1947 (layout
->size
- layout
->ro_after_init_size
) >> PAGE_SHIFT
);
1950 /* livepatching wants to disable read-only so it can frob module. */
1951 void module_disable_ro(const struct module
*mod
)
1953 if (!rodata_enabled
)
1956 frob_text(&mod
->core_layout
, set_memory_rw
);
1957 frob_rodata(&mod
->core_layout
, set_memory_rw
);
1958 frob_ro_after_init(&mod
->core_layout
, set_memory_rw
);
1959 frob_text(&mod
->init_layout
, set_memory_rw
);
1960 frob_rodata(&mod
->init_layout
, set_memory_rw
);
1963 void module_enable_ro(const struct module
*mod
, bool after_init
)
1965 if (!rodata_enabled
)
1968 frob_text(&mod
->core_layout
, set_memory_ro
);
1969 frob_text(&mod
->core_layout
, set_memory_x
);
1971 frob_rodata(&mod
->core_layout
, set_memory_ro
);
1973 frob_text(&mod
->init_layout
, set_memory_ro
);
1974 frob_text(&mod
->init_layout
, set_memory_x
);
1976 frob_rodata(&mod
->init_layout
, set_memory_ro
);
1979 frob_ro_after_init(&mod
->core_layout
, set_memory_ro
);
1982 static void module_enable_nx(const struct module
*mod
)
1984 frob_rodata(&mod
->core_layout
, set_memory_nx
);
1985 frob_ro_after_init(&mod
->core_layout
, set_memory_nx
);
1986 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
1987 frob_rodata(&mod
->init_layout
, set_memory_nx
);
1988 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
1991 static void module_disable_nx(const struct module
*mod
)
1993 frob_rodata(&mod
->core_layout
, set_memory_x
);
1994 frob_ro_after_init(&mod
->core_layout
, set_memory_x
);
1995 frob_writable_data(&mod
->core_layout
, set_memory_x
);
1996 frob_rodata(&mod
->init_layout
, set_memory_x
);
1997 frob_writable_data(&mod
->init_layout
, set_memory_x
);
2000 /* Iterate through all modules and set each module's text as RW */
2001 void set_all_modules_text_rw(void)
2005 if (!rodata_enabled
)
2008 mutex_lock(&module_mutex
);
2009 list_for_each_entry_rcu(mod
, &modules
, list
) {
2010 if (mod
->state
== MODULE_STATE_UNFORMED
)
2013 frob_text(&mod
->core_layout
, set_memory_rw
);
2014 frob_text(&mod
->init_layout
, set_memory_rw
);
2016 mutex_unlock(&module_mutex
);
2019 /* Iterate through all modules and set each module's text as RO */
2020 void set_all_modules_text_ro(void)
2024 if (!rodata_enabled
)
2027 mutex_lock(&module_mutex
);
2028 list_for_each_entry_rcu(mod
, &modules
, list
) {
2030 * Ignore going modules since it's possible that ro
2031 * protection has already been disabled, otherwise we'll
2032 * run into protection faults at module deallocation.
2034 if (mod
->state
== MODULE_STATE_UNFORMED
||
2035 mod
->state
== MODULE_STATE_GOING
)
2038 frob_text(&mod
->core_layout
, set_memory_ro
);
2039 frob_text(&mod
->init_layout
, set_memory_ro
);
2041 mutex_unlock(&module_mutex
);
2044 static void disable_ro_nx(const struct module_layout
*layout
)
2046 if (rodata_enabled
) {
2047 frob_text(layout
, set_memory_rw
);
2048 frob_rodata(layout
, set_memory_rw
);
2049 frob_ro_after_init(layout
, set_memory_rw
);
2051 frob_rodata(layout
, set_memory_x
);
2052 frob_ro_after_init(layout
, set_memory_x
);
2053 frob_writable_data(layout
, set_memory_x
);
2057 static void disable_ro_nx(const struct module_layout
*layout
) { }
2058 static void module_enable_nx(const struct module
*mod
) { }
2059 static void module_disable_nx(const struct module
*mod
) { }
2062 #ifdef CONFIG_LIVEPATCH
2064 * Persist Elf information about a module. Copy the Elf header,
2065 * section header table, section string table, and symtab section
2066 * index from info to mod->klp_info.
2068 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2070 unsigned int size
, symndx
;
2073 size
= sizeof(*mod
->klp_info
);
2074 mod
->klp_info
= kmalloc(size
, GFP_KERNEL
);
2075 if (mod
->klp_info
== NULL
)
2079 size
= sizeof(mod
->klp_info
->hdr
);
2080 memcpy(&mod
->klp_info
->hdr
, info
->hdr
, size
);
2082 /* Elf section header table */
2083 size
= sizeof(*info
->sechdrs
) * info
->hdr
->e_shnum
;
2084 mod
->klp_info
->sechdrs
= kmalloc(size
, GFP_KERNEL
);
2085 if (mod
->klp_info
->sechdrs
== NULL
) {
2089 memcpy(mod
->klp_info
->sechdrs
, info
->sechdrs
, size
);
2091 /* Elf section name string table */
2092 size
= info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_size
;
2093 mod
->klp_info
->secstrings
= kmalloc(size
, GFP_KERNEL
);
2094 if (mod
->klp_info
->secstrings
== NULL
) {
2098 memcpy(mod
->klp_info
->secstrings
, info
->secstrings
, size
);
2100 /* Elf symbol section index */
2101 symndx
= info
->index
.sym
;
2102 mod
->klp_info
->symndx
= symndx
;
2105 * For livepatch modules, core_kallsyms.symtab is a complete
2106 * copy of the original symbol table. Adjust sh_addr to point
2107 * to core_kallsyms.symtab since the copy of the symtab in module
2108 * init memory is freed at the end of do_init_module().
2110 mod
->klp_info
->sechdrs
[symndx
].sh_addr
= \
2111 (unsigned long) mod
->core_kallsyms
.symtab
;
2116 kfree(mod
->klp_info
->sechdrs
);
2118 kfree(mod
->klp_info
);
2122 static void free_module_elf(struct module
*mod
)
2124 kfree(mod
->klp_info
->sechdrs
);
2125 kfree(mod
->klp_info
->secstrings
);
2126 kfree(mod
->klp_info
);
2128 #else /* !CONFIG_LIVEPATCH */
2129 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2134 static void free_module_elf(struct module
*mod
)
2137 #endif /* CONFIG_LIVEPATCH */
2139 void __weak
module_memfree(void *module_region
)
2141 vfree(module_region
);
2144 void __weak
module_arch_cleanup(struct module
*mod
)
2148 void __weak
module_arch_freeing_init(struct module
*mod
)
2152 /* Free a module, remove from lists, etc. */
2153 static void free_module(struct module
*mod
)
2155 trace_module_free(mod
);
2157 mod_sysfs_teardown(mod
);
2159 /* We leave it in list to prevent duplicate loads, but make sure
2160 * that noone uses it while it's being deconstructed. */
2161 mutex_lock(&module_mutex
);
2162 mod
->state
= MODULE_STATE_UNFORMED
;
2163 mutex_unlock(&module_mutex
);
2165 /* Remove dynamic debug info */
2166 ddebug_remove_module(mod
->name
);
2168 /* Arch-specific cleanup. */
2169 module_arch_cleanup(mod
);
2171 /* Module unload stuff */
2172 module_unload_free(mod
);
2174 /* Free any allocated parameters. */
2175 destroy_params(mod
->kp
, mod
->num_kp
);
2177 if (is_livepatch_module(mod
))
2178 free_module_elf(mod
);
2180 /* Now we can delete it from the lists */
2181 mutex_lock(&module_mutex
);
2182 /* Unlink carefully: kallsyms could be walking list. */
2183 list_del_rcu(&mod
->list
);
2184 mod_tree_remove(mod
);
2185 /* Remove this module from bug list, this uses list_del_rcu */
2186 module_bug_cleanup(mod
);
2187 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2188 synchronize_sched();
2189 mutex_unlock(&module_mutex
);
2191 /* This may be empty, but that's OK */
2192 disable_ro_nx(&mod
->init_layout
);
2193 module_arch_freeing_init(mod
);
2194 module_memfree(mod
->init_layout
.base
);
2196 percpu_modfree(mod
);
2198 /* Free lock-classes; relies on the preceding sync_rcu(). */
2199 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2201 /* Finally, free the core (containing the module structure) */
2202 disable_ro_nx(&mod
->core_layout
);
2203 module_memfree(mod
->core_layout
.base
);
2206 update_protections(current
->mm
);
2210 void *__symbol_get(const char *symbol
)
2212 struct module
*owner
;
2213 const struct kernel_symbol
*sym
;
2216 sym
= find_symbol(symbol
, &owner
, NULL
, true, true);
2217 if (sym
&& strong_try_module_get(owner
))
2221 return sym
? (void *)sym
->value
: NULL
;
2223 EXPORT_SYMBOL_GPL(__symbol_get
);
2226 * Ensure that an exported symbol [global namespace] does not already exist
2227 * in the kernel or in some other module's exported symbol table.
2229 * You must hold the module_mutex.
2231 static int verify_export_symbols(struct module
*mod
)
2234 struct module
*owner
;
2235 const struct kernel_symbol
*s
;
2237 const struct kernel_symbol
*sym
;
2240 { mod
->syms
, mod
->num_syms
},
2241 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2242 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2243 #ifdef CONFIG_UNUSED_SYMBOLS
2244 { mod
->unused_syms
, mod
->num_unused_syms
},
2245 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2249 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2250 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2251 if (find_symbol(s
->name
, &owner
, NULL
, true, false)) {
2252 pr_err("%s: exports duplicate symbol %s"
2254 mod
->name
, s
->name
, module_name(owner
));
2262 /* Change all symbols so that st_value encodes the pointer directly. */
2263 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2265 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2266 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2267 unsigned long secbase
;
2270 const struct kernel_symbol
*ksym
;
2272 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2273 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2275 switch (sym
[i
].st_shndx
) {
2277 /* Ignore common symbols */
2278 if (!strncmp(name
, "__gnu_lto", 9))
2281 /* We compiled with -fno-common. These are not
2282 supposed to happen. */
2283 pr_debug("Common symbol: %s\n", name
);
2284 pr_warn("%s: please compile with -fno-common\n",
2290 /* Don't need to do anything */
2291 pr_debug("Absolute symbol: 0x%08lx\n",
2292 (long)sym
[i
].st_value
);
2296 /* Livepatch symbols are resolved by livepatch */
2300 ksym
= resolve_symbol_wait(mod
, info
, name
);
2301 /* Ok if resolved. */
2302 if (ksym
&& !IS_ERR(ksym
)) {
2303 sym
[i
].st_value
= ksym
->value
;
2308 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2311 pr_warn("%s: Unknown symbol %s (err %li)\n",
2312 mod
->name
, name
, PTR_ERR(ksym
));
2313 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2317 /* Divert to percpu allocation if a percpu var. */
2318 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2319 secbase
= (unsigned long)mod_percpu(mod
);
2321 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2322 sym
[i
].st_value
+= secbase
;
2330 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2335 /* Now do relocations. */
2336 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2337 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2339 /* Not a valid relocation section? */
2340 if (infosec
>= info
->hdr
->e_shnum
)
2343 /* Don't bother with non-allocated sections */
2344 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2347 /* Livepatch relocation sections are applied by livepatch */
2348 if (info
->sechdrs
[i
].sh_flags
& SHF_RELA_LIVEPATCH
)
2351 if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2352 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2353 info
->index
.sym
, i
, mod
);
2354 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2355 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2356 info
->index
.sym
, i
, mod
);
2363 /* Additional bytes needed by arch in front of individual sections */
2364 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2365 unsigned int section
)
2367 /* default implementation just returns zero */
2371 /* Update size with this section: return offset. */
2372 static long get_offset(struct module
*mod
, unsigned int *size
,
2373 Elf_Shdr
*sechdr
, unsigned int section
)
2377 *size
+= arch_mod_section_prepend(mod
, section
);
2378 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2379 *size
= ret
+ sechdr
->sh_size
;
2383 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2384 might -- code, read-only data, read-write data, small data. Tally
2385 sizes, and place the offsets into sh_entsize fields: high bit means it
2387 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2389 static unsigned long const masks
[][2] = {
2390 /* NOTE: all executable code must be the first section
2391 * in this array; otherwise modify the text_size
2392 * finder in the two loops below */
2393 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2394 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2395 { SHF_RO_AFTER_INIT
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2396 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2397 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2401 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2402 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2404 pr_debug("Core section allocation order:\n");
2405 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2406 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2407 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2408 const char *sname
= info
->secstrings
+ s
->sh_name
;
2410 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2411 || (s
->sh_flags
& masks
[m
][1])
2412 || s
->sh_entsize
!= ~0UL
2413 || strstarts(sname
, ".init"))
2415 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2416 pr_debug("\t%s\n", sname
);
2419 case 0: /* executable */
2420 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2421 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2423 case 1: /* RO: text and ro-data */
2424 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2425 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2427 case 2: /* RO after init */
2428 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2429 mod
->core_layout
.ro_after_init_size
= mod
->core_layout
.size
;
2431 case 4: /* whole core */
2432 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2437 pr_debug("Init section allocation order:\n");
2438 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2439 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2440 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2441 const char *sname
= info
->secstrings
+ s
->sh_name
;
2443 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2444 || (s
->sh_flags
& masks
[m
][1])
2445 || s
->sh_entsize
!= ~0UL
2446 || !strstarts(sname
, ".init"))
2448 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2449 | INIT_OFFSET_MASK
);
2450 pr_debug("\t%s\n", sname
);
2453 case 0: /* executable */
2454 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2455 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2457 case 1: /* RO: text and ro-data */
2458 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2459 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2463 * RO after init doesn't apply to init_layout (only
2464 * core_layout), so it just takes the value of ro_size.
2466 mod
->init_layout
.ro_after_init_size
= mod
->init_layout
.ro_size
;
2468 case 4: /* whole init */
2469 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2475 static void set_license(struct module
*mod
, const char *license
)
2478 license
= "unspecified";
2480 if (!license_is_gpl_compatible(license
)) {
2481 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2482 pr_warn("%s: module license '%s' taints kernel.\n",
2483 mod
->name
, license
);
2484 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2485 LOCKDEP_NOW_UNRELIABLE
);
2489 /* Parse tag=value strings from .modinfo section */
2490 static char *next_string(char *string
, unsigned long *secsize
)
2492 /* Skip non-zero chars */
2495 if ((*secsize
)-- <= 1)
2499 /* Skip any zero padding. */
2500 while (!string
[0]) {
2502 if ((*secsize
)-- <= 1)
2508 static char *get_modinfo(struct load_info
*info
, const char *tag
)
2511 unsigned int taglen
= strlen(tag
);
2512 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2513 unsigned long size
= infosec
->sh_size
;
2515 for (p
= (char *)infosec
->sh_addr
; p
; p
= next_string(p
, &size
)) {
2516 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2517 return p
+ taglen
+ 1;
2522 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2524 struct module_attribute
*attr
;
2527 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2529 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2533 static void free_modinfo(struct module
*mod
)
2535 struct module_attribute
*attr
;
2538 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2544 #ifdef CONFIG_KALLSYMS
2546 /* lookup symbol in given range of kernel_symbols */
2547 static const struct kernel_symbol
*lookup_symbol(const char *name
,
2548 const struct kernel_symbol
*start
,
2549 const struct kernel_symbol
*stop
)
2551 return bsearch(name
, start
, stop
- start
,
2552 sizeof(struct kernel_symbol
), cmp_name
);
2555 static int is_exported(const char *name
, unsigned long value
,
2556 const struct module
*mod
)
2558 const struct kernel_symbol
*ks
;
2560 ks
= lookup_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2562 ks
= lookup_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2563 return ks
!= NULL
&& ks
->value
== value
;
2567 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2569 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2571 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2572 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2577 if (sym
->st_shndx
== SHN_UNDEF
)
2579 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2581 if (sym
->st_shndx
>= SHN_LORESERVE
)
2583 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2585 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2586 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2587 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2589 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2594 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2595 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2600 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2607 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2608 unsigned int shnum
, unsigned int pcpundx
)
2610 const Elf_Shdr
*sec
;
2612 if (src
->st_shndx
== SHN_UNDEF
2613 || src
->st_shndx
>= shnum
2617 #ifdef CONFIG_KALLSYMS_ALL
2618 if (src
->st_shndx
== pcpundx
)
2622 sec
= sechdrs
+ src
->st_shndx
;
2623 if (!(sec
->sh_flags
& SHF_ALLOC
)
2624 #ifndef CONFIG_KALLSYMS_ALL
2625 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2627 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2634 * We only allocate and copy the strings needed by the parts of symtab
2635 * we keep. This is simple, but has the effect of making multiple
2636 * copies of duplicates. We could be more sophisticated, see
2637 * linux-kernel thread starting with
2638 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2640 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2642 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2643 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2645 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2647 /* Put symbol section at end of init part of module. */
2648 symsect
->sh_flags
|= SHF_ALLOC
;
2649 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2650 info
->index
.sym
) | INIT_OFFSET_MASK
;
2651 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2653 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2654 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2656 /* Compute total space required for the core symbols' strtab. */
2657 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2658 if (i
== 0 || is_livepatch_module(mod
) ||
2659 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2660 info
->index
.pcpu
)) {
2661 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2666 /* Append room for core symbols at end of core part. */
2667 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2668 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2669 mod
->core_layout
.size
+= strtab_size
;
2670 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2672 /* Put string table section at end of init part of module. */
2673 strsect
->sh_flags
|= SHF_ALLOC
;
2674 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2675 info
->index
.str
) | INIT_OFFSET_MASK
;
2676 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2678 /* We'll tack temporary mod_kallsyms on the end. */
2679 mod
->init_layout
.size
= ALIGN(mod
->init_layout
.size
,
2680 __alignof__(struct mod_kallsyms
));
2681 info
->mod_kallsyms_init_off
= mod
->init_layout
.size
;
2682 mod
->init_layout
.size
+= sizeof(struct mod_kallsyms
);
2683 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2687 * We use the full symtab and strtab which layout_symtab arranged to
2688 * be appended to the init section. Later we switch to the cut-down
2691 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2693 unsigned int i
, ndst
;
2697 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2699 /* Set up to point into init section. */
2700 mod
->kallsyms
= mod
->init_layout
.base
+ info
->mod_kallsyms_init_off
;
2702 mod
->kallsyms
->symtab
= (void *)symsec
->sh_addr
;
2703 mod
->kallsyms
->num_symtab
= symsec
->sh_size
/ sizeof(Elf_Sym
);
2704 /* Make sure we get permanent strtab: don't use info->strtab. */
2705 mod
->kallsyms
->strtab
= (void *)info
->sechdrs
[info
->index
.str
].sh_addr
;
2707 /* Set types up while we still have access to sections. */
2708 for (i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++)
2709 mod
->kallsyms
->symtab
[i
].st_info
2710 = elf_type(&mod
->kallsyms
->symtab
[i
], info
);
2712 /* Now populate the cut down core kallsyms for after init. */
2713 mod
->core_kallsyms
.symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2714 mod
->core_kallsyms
.strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2715 src
= mod
->kallsyms
->symtab
;
2716 for (ndst
= i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++) {
2717 if (i
== 0 || is_livepatch_module(mod
) ||
2718 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2719 info
->index
.pcpu
)) {
2721 dst
[ndst
++].st_name
= s
- mod
->core_kallsyms
.strtab
;
2722 s
+= strlcpy(s
, &mod
->kallsyms
->strtab
[src
[i
].st_name
],
2726 mod
->core_kallsyms
.num_symtab
= ndst
;
2729 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2733 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2736 #endif /* CONFIG_KALLSYMS */
2738 static void dynamic_debug_setup(struct module
*mod
, struct _ddebug
*debug
, unsigned int num
)
2742 #ifdef CONFIG_DYNAMIC_DEBUG
2743 if (ddebug_add_module(debug
, num
, mod
->name
))
2744 pr_err("dynamic debug error adding module: %s\n",
2749 static void dynamic_debug_remove(struct module
*mod
, struct _ddebug
*debug
)
2752 ddebug_remove_module(mod
->name
);
2755 void * __weak
module_alloc(unsigned long size
)
2757 return vmalloc_exec(size
);
2760 #ifdef CONFIG_DEBUG_KMEMLEAK
2761 static void kmemleak_load_module(const struct module
*mod
,
2762 const struct load_info
*info
)
2766 /* only scan the sections containing data */
2767 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2769 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2770 /* Scan all writable sections that's not executable */
2771 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2772 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2773 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2776 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2777 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2781 static inline void kmemleak_load_module(const struct module
*mod
,
2782 const struct load_info
*info
)
2787 #ifdef CONFIG_MODULE_SIG
2788 static int module_sig_check(struct load_info
*info
, int flags
)
2791 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2792 const void *mod
= info
->hdr
;
2795 * Require flags == 0, as a module with version information
2796 * removed is no longer the module that was signed
2799 info
->len
> markerlen
&&
2800 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2801 /* We truncate the module to discard the signature */
2802 info
->len
-= markerlen
;
2803 err
= mod_verify_sig(mod
, &info
->len
);
2807 info
->sig_ok
= true;
2811 /* Not having a signature is only an error if we're strict. */
2812 if (err
== -ENOKEY
&& !sig_enforce
&&
2813 !kernel_is_locked_down("Loading of unsigned modules"))
2818 #else /* !CONFIG_MODULE_SIG */
2819 static int module_sig_check(struct load_info
*info
, int flags
)
2823 #endif /* !CONFIG_MODULE_SIG */
2825 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2826 static int elf_header_check(struct load_info
*info
)
2828 if (info
->len
< sizeof(*(info
->hdr
)))
2831 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2832 || info
->hdr
->e_type
!= ET_REL
2833 || !elf_check_arch(info
->hdr
)
2834 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2837 if (info
->hdr
->e_shoff
>= info
->len
2838 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2839 info
->len
- info
->hdr
->e_shoff
))
2845 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2847 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2850 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2852 if (copy_from_user(dst
, usrc
, n
) != 0)
2862 #ifdef CONFIG_LIVEPATCH
2863 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2865 if (get_modinfo(info
, "livepatch")) {
2867 add_taint_module(mod
, TAINT_LIVEPATCH
, LOCKDEP_STILL_OK
);
2868 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2874 #else /* !CONFIG_LIVEPATCH */
2875 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2877 if (get_modinfo(info
, "livepatch")) {
2878 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2885 #endif /* CONFIG_LIVEPATCH */
2887 static void check_modinfo_retpoline(struct module
*mod
, struct load_info
*info
)
2889 if (retpoline_module_ok(get_modinfo(info
, "retpoline")))
2892 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
2896 /* Sets info->hdr and info->len. */
2897 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
2898 struct load_info
*info
)
2903 if (info
->len
< sizeof(*(info
->hdr
)))
2906 err
= security_kernel_read_file(NULL
, READING_MODULE
);
2910 /* Suck in entire file: we'll want most of it. */
2911 info
->hdr
= __vmalloc(info
->len
,
2912 GFP_KERNEL
| __GFP_NOWARN
, PAGE_KERNEL
);
2916 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
2924 static void free_copy(struct load_info
*info
)
2929 static int rewrite_section_headers(struct load_info
*info
, int flags
)
2933 /* This should always be true, but let's be sure. */
2934 info
->sechdrs
[0].sh_addr
= 0;
2936 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2937 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
2938 if (shdr
->sh_type
!= SHT_NOBITS
2939 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
2940 pr_err("Module len %lu truncated\n", info
->len
);
2944 /* Mark all sections sh_addr with their address in the
2946 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
2948 #ifndef CONFIG_MODULE_UNLOAD
2949 /* Don't load .exit sections */
2950 if (strstarts(info
->secstrings
+shdr
->sh_name
, ".exit"))
2951 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2955 /* Track but don't keep modinfo and version sections. */
2956 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
2957 info
->index
.vers
= 0; /* Pretend no __versions section! */
2959 info
->index
.vers
= find_sec(info
, "__versions");
2960 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2962 info
->index
.info
= find_sec(info
, ".modinfo");
2963 if (!info
->index
.info
)
2964 info
->name
= "(missing .modinfo section)";
2966 info
->name
= get_modinfo(info
, "name");
2967 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2973 * Set up our basic convenience variables (pointers to section headers,
2974 * search for module section index etc), and do some basic section
2977 * Return the temporary module pointer (we'll replace it with the final
2978 * one when we move the module sections around).
2980 static struct module
*setup_load_info(struct load_info
*info
, int flags
)
2986 /* Set up the convenience variables */
2987 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
2988 info
->secstrings
= (void *)info
->hdr
2989 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
2991 err
= rewrite_section_headers(info
, flags
);
2993 return ERR_PTR(err
);
2995 /* Find internal symbols and strings. */
2996 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2997 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
2998 info
->index
.sym
= i
;
2999 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
3000 info
->strtab
= (char *)info
->hdr
3001 + info
->sechdrs
[info
->index
.str
].sh_offset
;
3006 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
3007 if (!info
->index
.mod
) {
3008 pr_warn("%s: No module found in object\n",
3009 info
->name
?: "(missing .modinfo name field)");
3010 return ERR_PTR(-ENOEXEC
);
3012 /* This is temporary: point mod into copy of data. */
3013 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3016 * If we didn't load the .modinfo 'name' field, fall back to
3017 * on-disk struct mod 'name' field.
3020 info
->name
= mod
->name
;
3022 if (info
->index
.sym
== 0) {
3023 pr_warn("%s: module has no symbols (stripped?)\n", info
->name
);
3024 return ERR_PTR(-ENOEXEC
);
3027 info
->index
.pcpu
= find_pcpusec(info
);
3029 /* Check module struct version now, before we try to use module. */
3030 if (!check_modstruct_version(info
, mod
))
3031 return ERR_PTR(-ENOEXEC
);
3036 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
3038 const char *modmagic
= get_modinfo(info
, "vermagic");
3041 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
3044 /* This is allowed: modprobe --force will invalidate it. */
3046 err
= try_to_force_load(mod
, "bad vermagic");
3049 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
3050 pr_err("%s: version magic '%s' should be '%s'\n",
3051 info
->name
, modmagic
, vermagic
);
3055 if (!get_modinfo(info
, "intree")) {
3056 if (!test_taint(TAINT_OOT_MODULE
))
3057 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3059 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
3062 check_modinfo_retpoline(mod
, info
);
3064 if (get_modinfo(info
, "staging")) {
3065 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
3066 pr_warn("%s: module is from the staging directory, the quality "
3067 "is unknown, you have been warned.\n", mod
->name
);
3070 err
= check_modinfo_livepatch(mod
, info
);
3074 /* Set up license info based on the info section */
3075 set_license(mod
, get_modinfo(info
, "license"));
3080 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
3082 mod
->kp
= section_objs(info
, "__param",
3083 sizeof(*mod
->kp
), &mod
->num_kp
);
3084 mod
->syms
= section_objs(info
, "__ksymtab",
3085 sizeof(*mod
->syms
), &mod
->num_syms
);
3086 mod
->crcs
= section_addr(info
, "__kcrctab");
3087 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
3088 sizeof(*mod
->gpl_syms
),
3089 &mod
->num_gpl_syms
);
3090 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
3091 mod
->gpl_future_syms
= section_objs(info
,
3092 "__ksymtab_gpl_future",
3093 sizeof(*mod
->gpl_future_syms
),
3094 &mod
->num_gpl_future_syms
);
3095 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
3097 #ifdef CONFIG_UNUSED_SYMBOLS
3098 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
3099 sizeof(*mod
->unused_syms
),
3100 &mod
->num_unused_syms
);
3101 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
3102 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
3103 sizeof(*mod
->unused_gpl_syms
),
3104 &mod
->num_unused_gpl_syms
);
3105 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
3107 #ifdef CONFIG_CONSTRUCTORS
3108 mod
->ctors
= section_objs(info
, ".ctors",
3109 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3111 mod
->ctors
= section_objs(info
, ".init_array",
3112 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3113 else if (find_sec(info
, ".init_array")) {
3115 * This shouldn't happen with same compiler and binutils
3116 * building all parts of the module.
3118 pr_warn("%s: has both .ctors and .init_array.\n",
3124 #ifdef CONFIG_TRACEPOINTS
3125 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
3126 sizeof(*mod
->tracepoints_ptrs
),
3127 &mod
->num_tracepoints
);
3129 #ifdef HAVE_JUMP_LABEL
3130 mod
->jump_entries
= section_objs(info
, "__jump_table",
3131 sizeof(*mod
->jump_entries
),
3132 &mod
->num_jump_entries
);
3134 #ifdef CONFIG_EVENT_TRACING
3135 mod
->trace_events
= section_objs(info
, "_ftrace_events",
3136 sizeof(*mod
->trace_events
),
3137 &mod
->num_trace_events
);
3138 mod
->trace_evals
= section_objs(info
, "_ftrace_eval_map",
3139 sizeof(*mod
->trace_evals
),
3140 &mod
->num_trace_evals
);
3142 #ifdef CONFIG_TRACING
3143 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
3144 sizeof(*mod
->trace_bprintk_fmt_start
),
3145 &mod
->num_trace_bprintk_fmt
);
3147 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3148 /* sechdrs[0].sh_size is always zero */
3149 mod
->ftrace_callsites
= section_objs(info
, "__mcount_loc",
3150 sizeof(*mod
->ftrace_callsites
),
3151 &mod
->num_ftrace_callsites
);
3154 mod
->extable
= section_objs(info
, "__ex_table",
3155 sizeof(*mod
->extable
), &mod
->num_exentries
);
3157 if (section_addr(info
, "__obsparm"))
3158 pr_warn("%s: Ignoring obsolete parameters\n", mod
->name
);
3160 info
->debug
= section_objs(info
, "__verbose",
3161 sizeof(*info
->debug
), &info
->num_debug
);
3166 static int move_module(struct module
*mod
, struct load_info
*info
)
3171 /* Do the allocs. */
3172 ptr
= module_alloc(mod
->core_layout
.size
);
3174 * The pointer to this block is stored in the module structure
3175 * which is inside the block. Just mark it as not being a
3178 kmemleak_not_leak(ptr
);
3182 memset(ptr
, 0, mod
->core_layout
.size
);
3183 mod
->core_layout
.base
= ptr
;
3185 if (mod
->init_layout
.size
) {
3186 ptr
= module_alloc(mod
->init_layout
.size
);
3188 * The pointer to this block is stored in the module structure
3189 * which is inside the block. This block doesn't need to be
3190 * scanned as it contains data and code that will be freed
3191 * after the module is initialized.
3193 kmemleak_ignore(ptr
);
3195 module_memfree(mod
->core_layout
.base
);
3198 memset(ptr
, 0, mod
->init_layout
.size
);
3199 mod
->init_layout
.base
= ptr
;
3201 mod
->init_layout
.base
= NULL
;
3203 /* Transfer each section which specifies SHF_ALLOC */
3204 pr_debug("final section addresses:\n");
3205 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
3207 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3209 if (!(shdr
->sh_flags
& SHF_ALLOC
))
3212 if (shdr
->sh_entsize
& INIT_OFFSET_MASK
)
3213 dest
= mod
->init_layout
.base
3214 + (shdr
->sh_entsize
& ~INIT_OFFSET_MASK
);
3216 dest
= mod
->core_layout
.base
+ shdr
->sh_entsize
;
3218 if (shdr
->sh_type
!= SHT_NOBITS
)
3219 memcpy(dest
, (void *)shdr
->sh_addr
, shdr
->sh_size
);
3220 /* Update sh_addr to point to copy in image. */
3221 shdr
->sh_addr
= (unsigned long)dest
;
3222 pr_debug("\t0x%lx %s\n",
3223 (long)shdr
->sh_addr
, info
->secstrings
+ shdr
->sh_name
);
3229 static int check_module_license_and_versions(struct module
*mod
)
3231 int prev_taint
= test_taint(TAINT_PROPRIETARY_MODULE
);
3234 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3235 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3236 * using GPL-only symbols it needs.
3238 if (strcmp(mod
->name
, "ndiswrapper") == 0)
3239 add_taint(TAINT_PROPRIETARY_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
3241 /* driverloader was caught wrongly pretending to be under GPL */
3242 if (strcmp(mod
->name
, "driverloader") == 0)
3243 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3244 LOCKDEP_NOW_UNRELIABLE
);
3246 /* lve claims to be GPL but upstream won't provide source */
3247 if (strcmp(mod
->name
, "lve") == 0)
3248 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3249 LOCKDEP_NOW_UNRELIABLE
);
3251 if (!prev_taint
&& test_taint(TAINT_PROPRIETARY_MODULE
))
3252 pr_warn("%s: module license taints kernel.\n", mod
->name
);
3254 #ifdef CONFIG_MODVERSIONS
3255 if ((mod
->num_syms
&& !mod
->crcs
)
3256 || (mod
->num_gpl_syms
&& !mod
->gpl_crcs
)
3257 || (mod
->num_gpl_future_syms
&& !mod
->gpl_future_crcs
)
3258 #ifdef CONFIG_UNUSED_SYMBOLS
3259 || (mod
->num_unused_syms
&& !mod
->unused_crcs
)
3260 || (mod
->num_unused_gpl_syms
&& !mod
->unused_gpl_crcs
)
3263 return try_to_force_load(mod
,
3264 "no versions for exported symbols");
3270 static void flush_module_icache(const struct module
*mod
)
3272 mm_segment_t old_fs
;
3274 /* flush the icache in correct context */
3279 * Flush the instruction cache, since we've played with text.
3280 * Do it before processing of module parameters, so the module
3281 * can provide parameter accessor functions of its own.
3283 if (mod
->init_layout
.base
)
3284 flush_icache_range((unsigned long)mod
->init_layout
.base
,
3285 (unsigned long)mod
->init_layout
.base
3286 + mod
->init_layout
.size
);
3287 flush_icache_range((unsigned long)mod
->core_layout
.base
,
3288 (unsigned long)mod
->core_layout
.base
+ mod
->core_layout
.size
);
3293 int __weak
module_frob_arch_sections(Elf_Ehdr
*hdr
,
3301 /* module_blacklist is a comma-separated list of module names */
3302 static char *module_blacklist
;
3303 static bool blacklisted(const char *module_name
)
3308 if (!module_blacklist
)
3311 for (p
= module_blacklist
; *p
; p
+= len
) {
3312 len
= strcspn(p
, ",");
3313 if (strlen(module_name
) == len
&& !memcmp(module_name
, p
, len
))
3320 core_param(module_blacklist
, module_blacklist
, charp
, 0400);
3322 static struct module
*layout_and_allocate(struct load_info
*info
, int flags
)
3324 /* Module within temporary copy. */
3329 mod
= setup_load_info(info
, flags
);
3333 if (blacklisted(info
->name
))
3334 return ERR_PTR(-EPERM
);
3336 err
= check_modinfo(mod
, info
, flags
);
3338 return ERR_PTR(err
);
3340 /* Allow arches to frob section contents and sizes. */
3341 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3342 info
->secstrings
, mod
);
3344 return ERR_PTR(err
);
3346 /* We will do a special allocation for per-cpu sections later. */
3347 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3350 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3351 * layout_sections() can put it in the right place.
3352 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3354 ndx
= find_sec(info
, ".data..ro_after_init");
3356 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3358 /* Determine total sizes, and put offsets in sh_entsize. For now
3359 this is done generically; there doesn't appear to be any
3360 special cases for the architectures. */
3361 layout_sections(mod
, info
);
3362 layout_symtab(mod
, info
);
3364 /* Allocate and move to the final place */
3365 err
= move_module(mod
, info
);
3367 return ERR_PTR(err
);
3369 /* Module has been copied to its final place now: return it. */
3370 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3371 kmemleak_load_module(mod
, info
);
3375 /* mod is no longer valid after this! */
3376 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3378 percpu_modfree(mod
);
3379 module_arch_freeing_init(mod
);
3380 module_memfree(mod
->init_layout
.base
);
3381 module_memfree(mod
->core_layout
.base
);
3384 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3385 const Elf_Shdr
*sechdrs
,
3391 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3393 /* Sort exception table now relocations are done. */
3394 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3396 /* Copy relocated percpu area over. */
3397 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3398 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3400 /* Setup kallsyms-specific fields. */
3401 add_kallsyms(mod
, info
);
3403 /* Arch-specific module finalizing. */
3404 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3407 /* Is this module of this name done loading? No locks held. */
3408 static bool finished_loading(const char *name
)
3414 * The module_mutex should not be a heavily contended lock;
3415 * if we get the occasional sleep here, we'll go an extra iteration
3416 * in the wait_event_interruptible(), which is harmless.
3418 sched_annotate_sleep();
3419 mutex_lock(&module_mutex
);
3420 mod
= find_module_all(name
, strlen(name
), true);
3421 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
;
3422 mutex_unlock(&module_mutex
);
3427 /* Call module constructors. */
3428 static void do_mod_ctors(struct module
*mod
)
3430 #ifdef CONFIG_CONSTRUCTORS
3433 for (i
= 0; i
< mod
->num_ctors
; i
++)
3438 /* For freeing module_init on success, in case kallsyms traversing */
3439 struct mod_initfree
{
3440 struct rcu_head rcu
;
3444 static void do_free_init(struct rcu_head
*head
)
3446 struct mod_initfree
*m
= container_of(head
, struct mod_initfree
, rcu
);
3447 module_memfree(m
->module_init
);
3452 * This is where the real work happens.
3454 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3455 * helper command 'lx-symbols'.
3457 static noinline
int do_init_module(struct module
*mod
)
3460 struct mod_initfree
*freeinit
;
3462 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3467 freeinit
->module_init
= mod
->init_layout
.base
;
3470 * We want to find out whether @mod uses async during init. Clear
3471 * PF_USED_ASYNC. async_schedule*() will set it.
3473 current
->flags
&= ~PF_USED_ASYNC
;
3476 /* Start the module */
3477 if (mod
->init
!= NULL
)
3478 ret
= do_one_initcall(mod
->init
);
3480 goto fail_free_freeinit
;
3483 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3484 "follow 0/-E convention\n"
3485 "%s: loading module anyway...\n",
3486 __func__
, mod
->name
, ret
, __func__
);
3490 /* Now it's a first class citizen! */
3491 mod
->state
= MODULE_STATE_LIVE
;
3492 blocking_notifier_call_chain(&module_notify_list
,
3493 MODULE_STATE_LIVE
, mod
);
3496 * We need to finish all async code before the module init sequence
3497 * is done. This has potential to deadlock. For example, a newly
3498 * detected block device can trigger request_module() of the
3499 * default iosched from async probing task. Once userland helper
3500 * reaches here, async_synchronize_full() will wait on the async
3501 * task waiting on request_module() and deadlock.
3503 * This deadlock is avoided by perfomring async_synchronize_full()
3504 * iff module init queued any async jobs. This isn't a full
3505 * solution as it will deadlock the same if module loading from
3506 * async jobs nests more than once; however, due to the various
3507 * constraints, this hack seems to be the best option for now.
3508 * Please refer to the following thread for details.
3510 * http://thread.gmane.org/gmane.linux.kernel/1420814
3512 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3513 async_synchronize_full();
3515 ftrace_free_mem(mod
, mod
->init_layout
.base
, mod
->init_layout
.base
+
3516 mod
->init_layout
.size
);
3517 mutex_lock(&module_mutex
);
3518 /* Drop initial reference. */
3520 trim_init_extable(mod
);
3521 #ifdef CONFIG_KALLSYMS
3522 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3523 rcu_assign_pointer(mod
->kallsyms
, &mod
->core_kallsyms
);
3525 module_enable_ro(mod
, true);
3526 mod_tree_remove_init(mod
);
3527 disable_ro_nx(&mod
->init_layout
);
3528 module_arch_freeing_init(mod
);
3529 mod
->init_layout
.base
= NULL
;
3530 mod
->init_layout
.size
= 0;
3531 mod
->init_layout
.ro_size
= 0;
3532 mod
->init_layout
.ro_after_init_size
= 0;
3533 mod
->init_layout
.text_size
= 0;
3535 * We want to free module_init, but be aware that kallsyms may be
3536 * walking this with preempt disabled. In all the failure paths, we
3537 * call synchronize_sched(), but we don't want to slow down the success
3538 * path, so use actual RCU here.
3539 * Note that module_alloc() on most architectures creates W+X page
3540 * mappings which won't be cleaned up until do_free_init() runs. Any
3541 * code such as mark_rodata_ro() which depends on those mappings to
3542 * be cleaned up needs to sync with the queued work - ie
3543 * rcu_barrier_sched()
3545 call_rcu_sched(&freeinit
->rcu
, do_free_init
);
3546 mutex_unlock(&module_mutex
);
3547 wake_up_all(&module_wq
);
3554 /* Try to protect us from buggy refcounters. */
3555 mod
->state
= MODULE_STATE_GOING
;
3556 synchronize_sched();
3558 blocking_notifier_call_chain(&module_notify_list
,
3559 MODULE_STATE_GOING
, mod
);
3560 klp_module_going(mod
);
3561 ftrace_release_mod(mod
);
3563 wake_up_all(&module_wq
);
3567 static int may_init_module(void)
3569 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3576 * We try to place it in the list now to make sure it's unique before
3577 * we dedicate too many resources. In particular, temporary percpu
3578 * memory exhaustion.
3580 static int add_unformed_module(struct module
*mod
)
3585 mod
->state
= MODULE_STATE_UNFORMED
;
3588 mutex_lock(&module_mutex
);
3589 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3591 if (old
->state
!= MODULE_STATE_LIVE
) {
3592 /* Wait in case it fails to load. */
3593 mutex_unlock(&module_mutex
);
3594 err
= wait_event_interruptible(module_wq
,
3595 finished_loading(mod
->name
));
3603 mod_update_bounds(mod
);
3604 list_add_rcu(&mod
->list
, &modules
);
3605 mod_tree_insert(mod
);
3609 mutex_unlock(&module_mutex
);
3614 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3618 mutex_lock(&module_mutex
);
3620 /* Find duplicate symbols (must be called under lock). */
3621 err
= verify_export_symbols(mod
);
3625 /* This relies on module_mutex for list integrity. */
3626 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3628 module_enable_ro(mod
, false);
3629 module_enable_nx(mod
);
3631 /* Mark state as coming so strong_try_module_get() ignores us,
3632 * but kallsyms etc. can see us. */
3633 mod
->state
= MODULE_STATE_COMING
;
3634 mutex_unlock(&module_mutex
);
3639 mutex_unlock(&module_mutex
);
3643 static int prepare_coming_module(struct module
*mod
)
3647 ftrace_module_enable(mod
);
3648 err
= klp_module_coming(mod
);
3652 blocking_notifier_call_chain(&module_notify_list
,
3653 MODULE_STATE_COMING
, mod
);
3657 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3660 struct module
*mod
= arg
;
3663 if (strcmp(param
, "async_probe") == 0) {
3664 mod
->async_probe_requested
= true;
3668 /* Check for magic 'dyndbg' arg */
3669 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3671 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3675 /* Allocate and load the module: note that size of section 0 is always
3676 zero, and we rely on this for optional sections. */
3677 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3684 err
= module_sig_check(info
, flags
);
3688 err
= elf_header_check(info
);
3692 /* Figure out module layout, and allocate all the memory. */
3693 mod
= layout_and_allocate(info
, flags
);
3699 audit_log_kern_module(mod
->name
);
3701 /* Reserve our place in the list. */
3702 err
= add_unformed_module(mod
);
3706 #ifdef CONFIG_MODULE_SIG
3707 mod
->sig_ok
= info
->sig_ok
;
3709 pr_notice_once("%s: module verification failed: signature "
3710 "and/or required key missing - tainting "
3711 "kernel\n", mod
->name
);
3712 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3716 /* To avoid stressing percpu allocator, do this once we're unique. */
3717 err
= percpu_modalloc(mod
, info
);
3721 /* Now module is in final location, initialize linked lists, etc. */
3722 err
= module_unload_init(mod
);
3726 init_param_lock(mod
);
3728 /* Now we've got everything in the final locations, we can
3729 * find optional sections. */
3730 err
= find_module_sections(mod
, info
);
3734 err
= check_module_license_and_versions(mod
);
3738 /* Set up MODINFO_ATTR fields */
3739 setup_modinfo(mod
, info
);
3741 /* Fix up syms, so that st_value is a pointer to location. */
3742 err
= simplify_symbols(mod
, info
);
3746 err
= apply_relocations(mod
, info
);
3750 err
= post_relocation(mod
, info
);
3754 flush_module_icache(mod
);
3756 /* Now copy in args */
3757 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3758 if (IS_ERR(mod
->args
)) {
3759 err
= PTR_ERR(mod
->args
);
3760 goto free_arch_cleanup
;
3763 dynamic_debug_setup(mod
, info
->debug
, info
->num_debug
);
3765 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3766 ftrace_module_init(mod
);
3768 /* Finally it's fully formed, ready to start executing. */
3769 err
= complete_formation(mod
, info
);
3771 goto ddebug_cleanup
;
3773 err
= prepare_coming_module(mod
);
3777 /* Module is ready to execute: parsing args may do that. */
3778 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3780 unknown_module_param_cb
);
3781 if (IS_ERR(after_dashes
)) {
3782 err
= PTR_ERR(after_dashes
);
3783 goto coming_cleanup
;
3784 } else if (after_dashes
) {
3785 pr_warn("%s: parameters '%s' after `--' ignored\n",
3786 mod
->name
, after_dashes
);
3789 /* Link in to sysfs. */
3790 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3792 goto coming_cleanup
;
3794 if (is_livepatch_module(mod
)) {
3795 err
= copy_module_elf(mod
, info
);
3800 /* Get rid of temporary copy. */
3804 trace_module_load(mod
);
3806 return do_init_module(mod
);
3809 mod_sysfs_teardown(mod
);
3811 mod
->state
= MODULE_STATE_GOING
;
3812 destroy_params(mod
->kp
, mod
->num_kp
);
3813 blocking_notifier_call_chain(&module_notify_list
,
3814 MODULE_STATE_GOING
, mod
);
3815 klp_module_going(mod
);
3817 /* module_bug_cleanup needs module_mutex protection */
3818 mutex_lock(&module_mutex
);
3819 module_bug_cleanup(mod
);
3820 mutex_unlock(&module_mutex
);
3822 /* we can't deallocate the module until we clear memory protection */
3823 module_disable_ro(mod
);
3824 module_disable_nx(mod
);
3827 dynamic_debug_remove(mod
, info
->debug
);
3828 synchronize_sched();
3831 module_arch_cleanup(mod
);
3835 module_unload_free(mod
);
3837 mutex_lock(&module_mutex
);
3838 /* Unlink carefully: kallsyms could be walking list. */
3839 list_del_rcu(&mod
->list
);
3840 mod_tree_remove(mod
);
3841 wake_up_all(&module_wq
);
3842 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3843 synchronize_sched();
3844 mutex_unlock(&module_mutex
);
3847 * Ftrace needs to clean up what it initialized.
3848 * This does nothing if ftrace_module_init() wasn't called,
3849 * but it must be called outside of module_mutex.
3851 ftrace_release_mod(mod
);
3852 /* Free lock-classes; relies on the preceding sync_rcu() */
3853 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
3855 module_deallocate(mod
, info
);
3861 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
3862 unsigned long, len
, const char __user
*, uargs
)
3865 struct load_info info
= { };
3867 err
= may_init_module();
3871 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3874 err
= copy_module_from_user(umod
, len
, &info
);
3878 return load_module(&info
, uargs
, 0);
3881 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
3883 struct load_info info
= { };
3888 err
= may_init_module();
3892 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
3894 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
3895 |MODULE_INIT_IGNORE_VERMAGIC
))
3898 err
= kernel_read_file_from_fd(fd
, &hdr
, &size
, INT_MAX
,
3905 return load_module(&info
, uargs
, flags
);
3908 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
3910 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
3913 #ifdef CONFIG_KALLSYMS
3915 * This ignores the intensely annoying "mapping symbols" found
3916 * in ARM ELF files: $a, $t and $d.
3918 static inline int is_arm_mapping_symbol(const char *str
)
3920 if (str
[0] == '.' && str
[1] == 'L')
3922 return str
[0] == '$' && strchr("axtd", str
[1])
3923 && (str
[2] == '\0' || str
[2] == '.');
3926 static const char *symname(struct mod_kallsyms
*kallsyms
, unsigned int symnum
)
3928 return kallsyms
->strtab
+ kallsyms
->symtab
[symnum
].st_name
;
3931 static const char *get_ksymbol(struct module
*mod
,
3933 unsigned long *size
,
3934 unsigned long *offset
)
3936 unsigned int i
, best
= 0;
3937 unsigned long nextval
;
3938 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
3940 /* At worse, next value is at end of module */
3941 if (within_module_init(addr
, mod
))
3942 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
3944 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
3946 /* Scan for closest preceding symbol, and next symbol. (ELF
3947 starts real symbols at 1). */
3948 for (i
= 1; i
< kallsyms
->num_symtab
; i
++) {
3949 if (kallsyms
->symtab
[i
].st_shndx
== SHN_UNDEF
)
3952 /* We ignore unnamed symbols: they're uninformative
3953 * and inserted at a whim. */
3954 if (*symname(kallsyms
, i
) == '\0'
3955 || is_arm_mapping_symbol(symname(kallsyms
, i
)))
3958 if (kallsyms
->symtab
[i
].st_value
<= addr
3959 && kallsyms
->symtab
[i
].st_value
> kallsyms
->symtab
[best
].st_value
)
3961 if (kallsyms
->symtab
[i
].st_value
> addr
3962 && kallsyms
->symtab
[i
].st_value
< nextval
)
3963 nextval
= kallsyms
->symtab
[i
].st_value
;
3970 *size
= nextval
- kallsyms
->symtab
[best
].st_value
;
3972 *offset
= addr
- kallsyms
->symtab
[best
].st_value
;
3973 return symname(kallsyms
, best
);
3976 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3977 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3978 const char *module_address_lookup(unsigned long addr
,
3979 unsigned long *size
,
3980 unsigned long *offset
,
3984 const char *ret
= NULL
;
3988 mod
= __module_address(addr
);
3991 *modname
= mod
->name
;
3992 ret
= get_ksymbol(mod
, addr
, size
, offset
);
3994 /* Make a copy in here where it's safe */
3996 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
4004 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
4009 list_for_each_entry_rcu(mod
, &modules
, list
) {
4010 if (mod
->state
== MODULE_STATE_UNFORMED
)
4012 if (within_module(addr
, mod
)) {
4015 sym
= get_ksymbol(mod
, addr
, NULL
, NULL
);
4018 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
4028 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
4029 unsigned long *offset
, char *modname
, char *name
)
4034 list_for_each_entry_rcu(mod
, &modules
, list
) {
4035 if (mod
->state
== MODULE_STATE_UNFORMED
)
4037 if (within_module(addr
, mod
)) {
4040 sym
= get_ksymbol(mod
, addr
, size
, offset
);
4044 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
4046 strlcpy(name
, sym
, KSYM_NAME_LEN
);
4056 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
4057 char *name
, char *module_name
, int *exported
)
4062 list_for_each_entry_rcu(mod
, &modules
, list
) {
4063 struct mod_kallsyms
*kallsyms
;
4065 if (mod
->state
== MODULE_STATE_UNFORMED
)
4067 kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4068 if (symnum
< kallsyms
->num_symtab
) {
4069 *value
= kallsyms
->symtab
[symnum
].st_value
;
4070 *type
= kallsyms
->symtab
[symnum
].st_info
;
4071 strlcpy(name
, symname(kallsyms
, symnum
), KSYM_NAME_LEN
);
4072 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
4073 *exported
= is_exported(name
, *value
, mod
);
4077 symnum
-= kallsyms
->num_symtab
;
4083 static unsigned long mod_find_symname(struct module
*mod
, const char *name
)
4086 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4088 for (i
= 0; i
< kallsyms
->num_symtab
; i
++)
4089 if (strcmp(name
, symname(kallsyms
, i
)) == 0 &&
4090 kallsyms
->symtab
[i
].st_shndx
!= SHN_UNDEF
)
4091 return kallsyms
->symtab
[i
].st_value
;
4095 /* Look for this name: can be of form module:name. */
4096 unsigned long module_kallsyms_lookup_name(const char *name
)
4100 unsigned long ret
= 0;
4102 /* Don't lock: we're in enough trouble already. */
4104 if ((colon
= strnchr(name
, MODULE_NAME_LEN
, ':')) != NULL
) {
4105 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
4106 ret
= mod_find_symname(mod
, colon
+1);
4108 list_for_each_entry_rcu(mod
, &modules
, list
) {
4109 if (mod
->state
== MODULE_STATE_UNFORMED
)
4111 if ((ret
= mod_find_symname(mod
, name
)) != 0)
4119 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
4120 struct module
*, unsigned long),
4127 module_assert_mutex();
4129 list_for_each_entry(mod
, &modules
, list
) {
4130 /* We hold module_mutex: no need for rcu_dereference_sched */
4131 struct mod_kallsyms
*kallsyms
= mod
->kallsyms
;
4133 if (mod
->state
== MODULE_STATE_UNFORMED
)
4135 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4137 if (kallsyms
->symtab
[i
].st_shndx
== SHN_UNDEF
)
4140 ret
= fn(data
, symname(kallsyms
, i
),
4141 mod
, kallsyms
->symtab
[i
].st_value
);
4148 #endif /* CONFIG_KALLSYMS */
4150 /* Maximum number of characters written by module_flags() */
4151 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4153 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4154 static char *module_flags(struct module
*mod
, char *buf
)
4158 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
4160 mod
->state
== MODULE_STATE_GOING
||
4161 mod
->state
== MODULE_STATE_COMING
) {
4163 bx
+= module_flags_taint(mod
, buf
+ bx
);
4164 /* Show a - for module-is-being-unloaded */
4165 if (mod
->state
== MODULE_STATE_GOING
)
4167 /* Show a + for module-is-being-loaded */
4168 if (mod
->state
== MODULE_STATE_COMING
)
4177 #ifdef CONFIG_PROC_FS
4178 /* Called by the /proc file system to return a list of modules. */
4179 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
4181 mutex_lock(&module_mutex
);
4182 return seq_list_start(&modules
, *pos
);
4185 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
4187 return seq_list_next(p
, &modules
, pos
);
4190 static void m_stop(struct seq_file
*m
, void *p
)
4192 mutex_unlock(&module_mutex
);
4195 static int m_show(struct seq_file
*m
, void *p
)
4197 struct module
*mod
= list_entry(p
, struct module
, list
);
4198 char buf
[MODULE_FLAGS_BUF_SIZE
];
4201 /* We always ignore unformed modules. */
4202 if (mod
->state
== MODULE_STATE_UNFORMED
)
4205 seq_printf(m
, "%s %u",
4206 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
4207 print_unload_info(m
, mod
);
4209 /* Informative for users. */
4210 seq_printf(m
, " %s",
4211 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
4212 mod
->state
== MODULE_STATE_COMING
? "Loading" :
4214 /* Used by oprofile and other similar tools. */
4215 value
= m
->private ? NULL
: mod
->core_layout
.base
;
4216 seq_printf(m
, " 0x%px", value
);
4220 seq_printf(m
, " %s", module_flags(mod
, buf
));
4226 /* Format: modulename size refcount deps address
4228 Where refcount is a number or -, and deps is a comma-separated list
4231 static const struct seq_operations modules_op
= {
4239 * This also sets the "private" pointer to non-NULL if the
4240 * kernel pointers should be hidden (so you can just test
4241 * "m->private" to see if you should keep the values private).
4243 * We use the same logic as for /proc/kallsyms.
4245 static int modules_open(struct inode
*inode
, struct file
*file
)
4247 int err
= seq_open(file
, &modules_op
);
4250 struct seq_file
*m
= file
->private_data
;
4251 m
->private = kallsyms_show_value() ? NULL
: (void *)8ul;
4257 static const struct file_operations proc_modules_operations
= {
4258 .open
= modules_open
,
4260 .llseek
= seq_lseek
,
4261 .release
= seq_release
,
4264 static int __init
proc_modules_init(void)
4266 proc_create("modules", 0, NULL
, &proc_modules_operations
);
4269 module_init(proc_modules_init
);
4272 /* Given an address, look for it in the module exception tables. */
4273 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
4275 const struct exception_table_entry
*e
= NULL
;
4279 mod
= __module_address(addr
);
4283 if (!mod
->num_exentries
)
4286 e
= search_extable(mod
->extable
,
4293 * Now, if we found one, we are running inside it now, hence
4294 * we cannot unload the module, hence no refcnt needed.
4300 * is_module_address - is this address inside a module?
4301 * @addr: the address to check.
4303 * See is_module_text_address() if you simply want to see if the address
4304 * is code (not data).
4306 bool is_module_address(unsigned long addr
)
4311 ret
= __module_address(addr
) != NULL
;
4318 * __module_address - get the module which contains an address.
4319 * @addr: the address.
4321 * Must be called with preempt disabled or module mutex held so that
4322 * module doesn't get freed during this.
4324 struct module
*__module_address(unsigned long addr
)
4328 if (addr
< module_addr_min
|| addr
> module_addr_max
)
4331 module_assert_mutex_or_preempt();
4333 mod
= mod_find(addr
);
4335 BUG_ON(!within_module(addr
, mod
));
4336 if (mod
->state
== MODULE_STATE_UNFORMED
)
4341 EXPORT_SYMBOL_GPL(__module_address
);
4344 * is_module_text_address - is this address inside module code?
4345 * @addr: the address to check.
4347 * See is_module_address() if you simply want to see if the address is
4348 * anywhere in a module. See kernel_text_address() for testing if an
4349 * address corresponds to kernel or module code.
4351 bool is_module_text_address(unsigned long addr
)
4356 ret
= __module_text_address(addr
) != NULL
;
4363 * __module_text_address - get the module whose code contains an address.
4364 * @addr: the address.
4366 * Must be called with preempt disabled or module mutex held so that
4367 * module doesn't get freed during this.
4369 struct module
*__module_text_address(unsigned long addr
)
4371 struct module
*mod
= __module_address(addr
);
4373 /* Make sure it's within the text section. */
4374 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4375 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4380 EXPORT_SYMBOL_GPL(__module_text_address
);
4382 /* Don't grab lock, we're oopsing. */
4383 void print_modules(void)
4386 char buf
[MODULE_FLAGS_BUF_SIZE
];
4388 printk(KERN_DEFAULT
"Modules linked in:");
4389 /* Most callers should already have preempt disabled, but make sure */
4391 list_for_each_entry_rcu(mod
, &modules
, list
) {
4392 if (mod
->state
== MODULE_STATE_UNFORMED
)
4394 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4397 if (last_unloaded_module
[0])
4398 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4402 #ifdef CONFIG_MODVERSIONS
4403 /* Generate the signature for all relevant module structures here.
4404 * If these change, we don't want to try to parse the module. */
4405 void module_layout(struct module
*mod
,
4406 struct modversion_info
*ver
,
4407 struct kernel_param
*kp
,
4408 struct kernel_symbol
*ks
,
4409 struct tracepoint
* const *tp
)
4412 EXPORT_SYMBOL(module_layout
);